teco-manual.txt

                               Standard TECO


                     TEXT EDITOR AND CORRECTOR FOR THE
                     VAX-11, PDP-11, PDP-10, and PDP-8


                USER'S GUIDE AND LANGUAGE REFERENCE MANUAL


                             May 1985 Edition


                            TECO-11 VERSION  40
                            TECO-10 VERSION   3
                            TECO-8  VERSION   7




















     May, 1985

     Standard TECO



     The information in this document is  subject  to  change  without
     notice  and  should  not  be construed as a commitment by Digital
     Equipment Corporation or by DECUS.

     Neither Digital Equipment Corporation,  DECUS,  nor  the  authors
     assume  any  responsibility  for  the  use or reliability of this
     document or the described software.



                     Copyright (C) 1979, 1985 TECO SIG

               General permission to copy or modify, but not
               for  profit, is hereby granted, provided that
               the above copyright notice  is  included  and
               reference  made to the fact that reproduction
               privileges were granted by the TECO SIG.

     Standard TECO                                              PAGE i



                                 CONTENTS




      INTRODUCTION                                                 1

      PREFACE TO THE MAY 1985 EDITION                              4

      CHAPTER 1        BASICS OF TECO                              7

              1.1      USING TECO                                  7
              1.2      DATA STRUCTURE FUNDAMENTALS                 9
              1.3      FILE SELECTION COMMANDS                    10
              1.3.1       Simplified File Selection               10
              1.3.2       Input File Specification (ER command)   11
              1.3.3       Output File Specification (EW command)  12
              1.3.4       Closing Files (EX command)              13
              1.4      INPUT AND OUTPUT COMMANDS                  14
              1.5      POINTER POSITIONING COMMANDS               15
              1.6      TYPE OUT COMMANDS                          16
              1.6.1       Immediate Inspection Commands           17
              1.7      TEXT MODIFICATION COMMANDS                 18
              1.8      SEARCH COMMANDS                            19
              1.9      SAMPLE EDITING JOB                         20

      INTERLUDE                                                   23

      CHAPTER 2        INVOKING TECO                              24

              2.1      RUNNING TECO                               24
              2.2      CREATING A NEW FILE                        24
              2.3      EDITING AN EXISTING FILE                   24
              2.4      SWITCHES ON TECO AND MAKE COMMANDS         25
              2.5      INVOKING A TECO PROGRAM                    26
              2.6      USER INITIALIZATION                        27

      CHAPTER 3        CONVENTIONS AND STRUCTURES                 29

              3.1      TECO CHARACTER SET                         29
              3.2      TECO COMMAND FORMAT                        30
              3.2.1       Numeric Arguments                       31
              3.2.2       Text Arguments                          32
              3.2.3       Colon Modifiers                         33
              3.3      DATA STRUCTURES                            34
              3.3.1       Text Buffer                             35
              3.3.2       Q-registers                             36
              3.3.3       Q-register Push-down List               37
              3.3.4       Numeric Values and Flags                37

     Standard TECO                                             PAGE ii



      CHAPTER 4        COMMAND STRING EDITING                     38

              4.1         Immediate Action Editing Characters     38
              4.2         Immediate Action Commands               41
              4.3         Introduction to Macros                  43
              4.4         Immediate ESCAPE-Sequence Commands      44
              4.5         Operating System Character Filters      46

      CHAPTER 5        COMMAND DESCRIPTIONS                       48

              5.1      FILE SPECIFICATION COMMANDS                49
              5.1.1       File Opening Commands                   49
              5.1.2       File Specification Switches             51
              5.1.3       File Close and Exit Commands            51
              5.1.4       Secondary Stream Commands               54
              5.1.5       Wildcard Commands                       56
              5.1.6       Direct I/O to Q-Registers               56
              5.2      PAGE MANIPULATION COMMANDS                 58
              5.3      BUFFER POINTER MANIPULATION COMMANDS       61
              5.4      TEXT TYPE OUT COMMANDS                     63
              5.5      DELETION COMMANDS                          66
              5.6      INSERTION COMMANDS                         68
              5.7      SEARCH COMMANDS                            70
              5.8      SEARCH ARGUMENTS                           76
              5.9      Q-REGISTER MANIPULATION                    80
              5.10     ARITHMETIC AND EXPRESSIONS                 86
              5.11     SPECIAL NUMERIC VALUES                     89
              5.12     COMMAND LOOPS                              94
              5.13     BRANCHING COMMANDS                         95
              5.14     CONDITIONAL EXECUTION COMMANDS            101
              5.15     RETRIEVING ENVIRONMENT CHARACTERISTICS    103
              5.16     MODE CONTROL FLAGS                        105
              5.17     SCOPE COMMANDS                            113
              5.17.1      Video Terminal Scope Commands          113
              5.17.2      Refresh Scope Commands                 116
              5.18     PROGRAMMING AIDS                          117
              5.18.1      Text Formatting                        117
              5.18.2      Comments                               117
              5.18.3      Messages                               118
              5.18.4      Tracing                                119
              5.18.5      Convenience Characters                 119
              5.18.6      Memory Expansion                       120
              5.18.7      Case Control                           121
              5.19     MANIPULATING LARGE PAGES                  122
              5.20     TECHNIQUES AND EXAMPLES                   123

     Standard TECO                                            PAGE iii



      APPENDIX A       ASCII CHARACTER SET                       128

      APPENDIX B       ERROR MESSAGES                            137

      APPENDIX C       INCOMPATIBLE, OBSOLETE, AND SYSTEM-SPECIFIC
                       COMMANDS                                  145

              C.1      SPECIFIC FEATURES OF TECO-11              145
              C.1.1       TECO Commands                          145
              C.1.2       String Build Constructs                147
              C.2      SPECIFIC FEATURES OF RT-11                148
              C.3      SPECIFIC FEATURES OF RSTS/E               148
              C.4      SPECIFIC FEATURES OF RSX-11/M, RSX-11/D,
                       and IAS                                   149
              C.5      SPECIFIC FEATURES OF VAX/VMS              149
              C.6      SPECIFIC FEATURES OF OS/8                 149
              C.7      SPECIFIC FEATURES OF TOPS-10              150

      APPENDIX D       RT-11 OPERATING CHARACTERISTICS           153

      APPENDIX E       RSTS/E OPERATING CHARACTERISTICS          157

      APPENDIX F       RSX-11 OPERATING CHARACTERISTICS          160

      APPENDIX G       VAX/VMS OPERATING CHARACTERISTICS         167

      APPENDIX H       OS/8 OPERATING CHARACTERISTICS            175

      APPENDIX I       TOPS-10 OPERATING CHARACTERISTICS         187

      APPENDIX J       BASIC-PLUS/BASIC-PLUS-2 HANDLING          194

      GLOSSARY                                                   197

      INDEX                                                      214

     Standard TECO                                              PAGE 1
     Introduction


                               INTRODUCTION

     TECO is a powerful text editing  language  available  under  most
     DIGITAL  operating systems.  TECO may be used to edit any form of
     ASCII text:  program sources, command procedures, or manuscripts,
     for  example.   TECO  is  a  character-oriented  editor, and also
     offers a number of facilities for dealing with lines of text.

     You can use TECO interactively, issuing commands which are to  be
     executed as soon as they are typed in.  (TECO is an interpreter.)
     In this mode, TECO can be used for tasks ranging from very simple
     to quite complex.

     You can write sequences of commands called macros, which  can  be
     stored  and  then  invoked  by  short  commands  or  even  single
     keystrokes.  You can write sequences of commands  to  be  run  as
     TECO   programs,   and  store  them  on  disk  for  execution  at
     convenience.

     TECO can be used as an implementation language,  as  it  provides
     powerful   primitive   functions   for  text  processing,  screen
     handling, and keyboard management.  (The VTEDIT program  included
     with  some  TECO  distributions  is  an  example of a full keypad
     editor developed in the TECO language.)

     TECO correctly handles most sequential ASCII formats supported by
     the  operating  systems upon which it runs.  It provides flexible
     pattern-matching constructs for text searching, file wildcarding,
     and  special  support  for editing BASIC-PLUS/BASIC-PLUS-2 source
     programs.   A  split  screen  scrolling  feature  allows  command
     dialogue to share the screen with an automatically-updated window
     into the editing buffer.

     TECO's syntax  is  terse;   commands  are  designed  to  minimize
     keystrokes.   Also,  the  versatility  of TECO "in all its glory"
     makes it complex.  However, just a few commands  suffice  to  get
     real  work  done,  and  a novice TECO user can begin creating and
     editing text files after only a few hours of  instruction.   More
     powerful features can be learned one at a time, and at leisure.

     This manual presents TECO in two stages.  The first part (Chapter
     1)  contains basic information and introduces that set of "just a
     few" commands.

     Subsequent chapters describe the full TECO command set, including
     a  review  of  the  those commands presented in Chapter 1.  These
     chapters also introduce the concept  of  TECO  as  a  programming
     language  and  explain how basic editing commands may be combined
     into  "programs"  sophisticated  enough  to   handle   the   most
     complicated editing tasks.

     The early sections of this manual include few  specific  examples
     of  commands,  since all TECO commands have a consistent, logical

     Standard TECO                                              PAGE 2
     Introduction


     format which will quickly become apparent to the beginning  user.
     There  is,  however, an extensive example at the end of Chapter 1
     which employs most of the commands introduced up to  that  point.
     Students  of  TECO  should  experiment with each command as it is
     introduced, and then duplicate the examples on their computer.

     (If a video terminal which supports split-screen  scrolling  such
     as  a  member of the VT100 or VT200 families is available and the
     TECO being used supports it, seeing both your commands and  their
     effects  in  the  text  buffer  simultaneously  can make learning
     easier.  A command such as "5,7:W" allows  5  lines  for  command
     dialogue,  while  "watching"  the text buffer on the remainder of
     the screen.  The 7:W command is described in Table 5-17B.)

     This manual is intended to be a reference manual, and except  for
     Chapter 1 is not a tutorial.  After Chapter 1, it is assumed that
     the reader has a general familiarity with TECO and  is  referring
     to this manual to find detailed information.


                                 Notation

     The following notation  is  used  in  this  manual  to  represent
     special characters:

           Notation      ASCII code (octal)       Name

           <NULL>          0                      Null
           <BS>           10                      Backspace
           <TAB>          11                      Tab
           <LF>           12                      Line Feed
           <VT>           13                      Vertical Tab
           <FF>           14                      Form Feed
           <CR>           15                      Carriage Return
           <ESCAPE> or $  33                      ESCape or Altmode
           <CTRL/x>        -                      Control-x
           <space>        40                      Space
           <DELETE>      177                      Delete or Rubout

           <DELIM> or `    -                      See below

     <DELIM> is a character used to signify the end  of  text  strings
     and  TECO commands typed at the console.  (TECO presumes that you
     may need to deal with carriage return and line feed  as  ordinary
     characters  in  ASCII  text, so another character must be used as
     TECO's text-string and command-string delimiter.)

     When a command string is  being  executed,  TECO  looks  for  the
     ESCape  character  (octal  033)  as  its  delimiter.   Some newer
     terminals, however, no longer possess an ESCape key.   Late-model
     TECO's  are  capable  of  recognizing  a  surrogate  (some other,
     user-specified) character as signifying an ESCape when  typed  at
     the  console.   Such a character echos as accent grave -- you see

     Standard TECO                                              PAGE 3
     Introduction


     an ` character, and TECO receives  an  ESCape  character.   (Note
     that  TECO  programs,  command  files,  and macros cannot use the
     surrogate, since it is translated to ESCape only when you type it
     at  the console.) For details on choosing a surrogate for ESCape,
     see the EE flag or the 8192 ET bit (section 5.16).

     Throughout this manual, the term <DELIM> is used to mean whatever
     character  you type as a text-string or command-string delimiter.
     The ` character is used throughout to mean whichever character is
     echoed  for  a  keystroke  which passes an ESCape to TECO;  if no
     ESCape surrogate is active, you will see a $ instead.

     Control  characters,  <CTRL/x>,  are  produced  by  striking  the
     CONTROL key and a character key simultaneously.

     Throughout this manual, upper case characters  will  be  used  to
     represent TECO commands.

     Standard TECO                                              PAGE 4
     Preface to the May 1985 edition


                      PREFACE TO THE MAY 1985 EDITION


     Trading in the ESCape key

          In the beginning, terminals had ESCape keys.  (Go  back  far
          enough  and  the  device TT:  stands for might actually have
          existed on the system, too.) Programs wanting to treat  <CR>
          &  Co.  as data needed another character to serve as command
          delimiter, and ESCape looked available.

          Times   change.    Welcome   to   ESCape    sequences,    to
          cursor-control and function keys.  Farewell to $$.

          See the Introduction for the notation used in  this  manual.
          Hello ``.


     Changes to the manual

          This  edition  of  the  manual  incorporates  new   material
          pertinent  to the enhancements to TECO-11 between Version 36
          and Version 40 (see below).

          Although this manual is still not intended to be a tutorial,
          some "how to learn" suggestions (such as use of split-screen
          scrolling) were added, as were indications of how  TECO  can
          be used to build custom-designed editors.

          Numerous smaller changes were  also  made:   clarifications,
          new  index  and  glossary  entries,  additional  explanatory
          material and cross referrals, correction of old  typographic
          errors, and (no doubt) addition of new ones.

     Standard TECO                                              PAGE 5
     Preface to the May 1985 edition


     From Version 36 to Version 40 - affected section numbers

        Manual organization/additions --

          Introduction to Macros (new section), 4.3

          Split-screen scrolling, 5.17

          "Immediate action commands" renamed
          to "immediate inspection commands", 1,6.1

          "Immediate action editing characters" (new name), 4.1

          VAX/VMS filespec qualifiers, format/attribute table, G.11

          Eight-bit ASCII character set table, Appendix A

          Handling for BASIC-PLUS-x source files, Appendix J

        "Significant" software changes --

          ESCape surrogate - EE flag, 8192 ET bit, 5.16

          Reverse paging (-P, et al, VAX/VMS only), 5.2

          Reverse searching (-N, et al, VAX/VMS only), 5.7

          Local Q-registers, 3.3.2

          Local Q-register manipulation, 5.9

          Immediate ESCape-sequence commands, 4.4

          :^T, read/decode a keystroke, 5.11

          32 ED bit controls immediate ESC-seq commands, 5.16

          Acceptance and handling of 8-bit characters, [throughout]

          Typeout of 8-bit data, and the 4096 ET bit, 5.16

          n:^T, one-shot binary-mode character typeout, 5.4

          TECO HELP facilities on VAX/VMS, G.13

        "Minor" software changes --

          ^W as immediate mode command (screen re-paint), 4.2

          <DELIM> character as immediate inspection command, 1.6.1,
           4.2

          Null tag allowed in computed GOTO, 5.13

     Standard TECO                                              PAGE 6
     Preface to the May 1985 edition



          nFRtext` command (replace n characters), 5.6

          m,nFRtext` command (replace from m to n), 5.6

          ^E (form feed flag) can now be user-set, 5.11

          Setting 1:W changes width and O/S characteristic, 5.17

          WRAP/NOWRAP set by 256 ET bit on VAX/VMS, 5.16

          128 ED bit inhibits auto-refresh in split scrolling, 5.16

          Search matching with diacritical marks, 5.16

          New 0:W codes for VT102 and GIGI scope types, 5.17

          VAX/VMS handling of ^T (disabled when), 4.5

     Standard TECO                                              PAGE 7
     Basics of TECO


                                 CHAPTER 1

                              BASICS OF TECO


     1.1 USING TECO

     TECO may be called from command level by typing  the  appropriate
     command, followed by a carriage return:

           For RT-11, OS/8, TOPS-10, and TOPS-20  R TECO

           For RSTS/E                             RUN TECO$:TECO -or-
                                                  EDIT/TECO

           For RSX-11                             RUN $TEC

           For VAX/VMS                            RUN SYS$SYSTEM:TECO

     TECO will respond by printing an asterisk at the left  margin  to
     indicate  that  it  is  ready  to  accept user commands.  At this
     point, you may type one or more commands.

     A TECO command consists of one or two characters  which  cause  a
     specific  operation  to  be performed.  Some TECO commands may be
     preceded or followed  by  arguments.   Arguments  may  be  either
     numeric  or  textual.   A  numeric  argument is simply an integer
     value which can be used to indicate, for example, the  number  of
     times  a command should be executed.  A text argument is a string
     of ASCII characters which might be, for example, words of text or
     a file specification.

     If a command requires a numeric argument,  the  numeric  argument
     always  precedes  the  command.   If  a  command  requires a text
     argument, the text argument always  follows  the  command.   Each
     text  argument  is  terminated  by a special character (usually a
     <DELIM>  character,  which  TECO  hears  as  an  ESCape   -   see
     Introduction).   This  indicates  to TECO that the next character
     typed will be the first character of a new command.

     TECO accumulates commands as they are typed in a command  string,
     and  executes  commands  upon  receipt of two consecutive <DELIM>
     characters.  <DELIM> may be any character  you  select  (if  your
     TECO   and   operating   system  support  user-selectable  ESCape
     surrogates - see sections on ET and EE flags).  When you type the
     character you have designated as <DELIM>, TECO receives an ESCape
     character, and an ` (accent grave) is echoed.  (If  you  are  not
     using  an  ESCape surrogate -- that is, you are actually pressing
     an ESCape key -- a dollar  sign  is  echoed.)  The  accent  grave
     character is used in examples throughout this manual to represent
     typed <DELIM>s.  Note that the carriage return character  has  no
     special  significance  to  TECO;   only the <DELIM><DELIM> forces
     execution of the command string.

     Standard TECO                                              PAGE 8
     Using TECO


     TECO executes command strings from left to right until either all
     commands have been executed or a command error is recognized.  It
     then prints an asterisk to signal that additional commands may be
     entered.

     If TECO encounters an  erroneous  command,  it  prints  an  error
     message and ignores the erroneous command as well as all commands
     which follow it.  All error messages are of the form:

     ?XXX   Message

     where XXX is an error code and the message is  a  description  of
     the error.  Some error messages mention the specific character or
     string of characters in error.  In  these  error  messages,  TECO
     represents the non-printing special characters as follows:

          Character      Form Displayed

          <TAB>          <TAB>
          <LF>           <LF>
          <VT>           <VT>
          <FF>           <FF>
          <CR>           <CR>
          <ESCAPE>       <ESC>
          <CTRL/x>       <^x>


     Every error message is  followed  by  an  asterisk  at  the  left
     margin,  indicating  that  TECO  is  ready  to  accept additional
     commands.  If you type a single question mark character  after  a
     TECO-generated  error  message,  TECO  will  print  the erroneous
     command string up to and including the character which caused the
     error  message.   This  helps  you to find errors in long command
     strings and to  determine  how  much  of  a  command  string  was
     executed before the error was encountered.

     You can correct typing errors by hitting the  DELETE  key,  which
     may  be  labeled DEL or RUBOUT on your keyboard.  Each depression
     of the DELETE key deletes one character and  echoes  it  on  your
     terminal,  beginning  with  the  last  character  typed.  If your
     terminal is a CRT, TECO will actually erase the deleted character
     from  the  screen.   You can delete an entire command string this
     way, if necessary.  To delete an entire line of  commands,  enter
     the  character  <CTRL/U>,  typed  by holding down the CONTROL key
     while depressing the "U" key.

     When you are done editing, use the EX command to  exit  TECO,  as
     described below in section 1.3.4.

     Standard TECO                                              PAGE 9
     Data Structure Fundamentals


     1.2 DATA STRUCTURE FUNDAMENTALS

     TECO considers any string of ASCII codes to  be  text.   Text  is
     broken  down  into  units  of  characters,  lines,  and pages.  A
     character is one ASCII code.  A line of text is a string of ASCII
     codes  including one line terminator (usually a line feed) as the
     last character on the line.  A page of text is a string of  ASCII
     codes  including one form feed character as the last character on
     the page.

     TECO maintains a text buffer in which text is stored.  The buffer
     usually  contains one page of text, but the terminating form feed
     character never appears in the buffer.   TECO  also  maintains  a
     text buffer pointer.  The pointer is a movable position indicator
     which is never located directly on a  character,  but  is  always
     between characters:  between two characters in the buffer, before
     the first character in the buffer, or after the last character in
     the buffer.

     Line feed and form feed characters are inserted automatically  by
     TECO.   A  line  feed is automatically appended to every carriage
     return typed to TECO and a form feed is appended to the  contents
     of  the  buffer by certain output commands.  Additional line feed
     and form feed characters may be entered into the buffer as  text.
     If  a  form  feed  character  is entered into the buffer, it will
     cause a page break upon output;  text  following  the  form  feed
     will begin a new page.

     Finally, TECO maintains an input file and an output file, both of
     which  are  selected  by  the  user  through  file  specification
     commands.  The input file may be on any device  from  which  text
     may  be  accepted.  The output file may be on any device on which
     edited text may be written.

     TECO functions as a "pipeline" editor.  Text  is  read  from  the
     input  file  into the text buffer, and is written from the buffer
     onto the output file.   In  the  VAX/VMS  implementation,  it  is
     possible  to  "back up" as well as page forward in the file being
     edited.  In other implementations, once text has been written  to
     the  output file, it cannot be accessed again without closing the
     output file and reopening it as an input file.

     Standard TECO                                             PAGE 10
     File Selection Commands


     1.3 FILE SELECTION COMMANDS

     Input and output files may be specified to TECO in several  ways.
     The   following  sections  present  first  a  simple  method  for
     specifying files,  and  then  more  sophisticated  commands  that
     permit flexible file selection.


                                   NOTE

         All of the following file selection  commands  are  shown
         with  a  general  argument  of  "filespec".   The  actual
         contents of this filespec argument are  operating  system
         dependent.  See the operating characteristics appendices.
         Examples include a mixture of  file  specifications  from
         various operating systems.


     1.3.1 Simplified File Selection

     For most simple  applications,  you  can  use  special  operating
     system  commands to specify the name of the file you wish to edit
     at the same time that you start up TECO.

     To create a new file:

                               MAKE filespec

     This command starts up TECO and creates the  specified  file  for
     output.

     To edit an existing file:

                               TECO filespec

     This command starts up TECO and  opens  the  specified  file  for
     editing  while  preserving  the original file (as a backup file).
     It also automatically brings the first page of the file into  the
     text  buffer.   These functions simulate the EB command described
     in Chapter 5.

     If any of the  above  commands  do  not  seem  to  work  on  your
     operating   system,   consult   the   appropriate   appendix  for
     information  about  how  to  install  TECO  and  its   associated
     operating system commands.

     Standard TECO                                             PAGE 11
     File Selection Commands


     1.3.2 Input File Specification (ER command)

     TECO will  accept  input  text  from  any  input  device  in  the
     operating  system.  The input device may be specified by the text
     string supplied in the ER  command  (and  which,  like  any  text
     argument,  is terminated by a <DELIM> character).  The ER command
     causes TECO to open the specified file or print an error  message
     if  the  file  is  not  found.   This  command does not cause any
     portion of the file to be read into  the  text  buffer,  however.
     The following examples illustrate use of the ER command.


     COMMAND             FUNCTION

     ERfilespec`         General  form  of  the   ER   command   where
                         "filespec"  is  the  designation of the input
                         file.  The command is terminated by a <DELIM>
                         character.

     ERPR:`              Prepare to read an input file from the  paper
                         tape reader.

     ERPROG.MAC`         Prepare to read input file PROG.MAC from  the
                         system's default device.

     ERDX1:PROG.FOR`     Prepare to  read  input  file  PROG.FOR  from
                         DX1:.


     TECO will only keep one  input  and  one  output  file  open  and
     selected  at  a  time.   The current input file may be changed by
     simply using the ER command to specify a new file.

     It is not always necessary to specify an input file.  If you want
     to  create  a  file  without  using any previously edited text as
     input, you  may  type  commands  to  insert  the  necessary  text
     directly  into  the text buffer from the keyboard and, at the end
     of each page, write the contents of the  buffer  onto  an  output
     file.   Since  all  input is supplied from the keyboard, no input
     file is necessary.

     Standard TECO                                             PAGE 12
     File Selection Commands


     1.3.3 Output File Specification (EW command)

     TECO will write  output  text  onto  any  output  device  in  the
     operating  system.   The output file may be specified by means of
     the text string supplied in an EW command.  If the output  device
     is  a file-structured device (for example, a disk), the file name
     and any extension must be supplied.  If a file name is  specified
     but  no  device  is  explicitly  specified,  the system's default
     device is assumed.  The following examples illustrate use of  the
     EW command.


     COMMAND             FUNCTION

     EWfilespec`         General  form  of  the   EW   command   where
                         "filespec"  is  the designation of the output
                         file.  The command is terminated by a <DELIM>
                         character.

     EWSYS:TEXT.LST`     Prepare to  write  output  file  TEXT.LST  on
                         SYS:.

     EWPROG`             Prepare to write  output  file  PROG  on  the
                         system's default device.

     ERDX1:INPUT.MAC`EWOUTPUT.MAC``
                         Open an input file INPUT.MAC to be  found  on
                         DX1:    and   open   an   output  file  named
                         OUTPUT.MAC.  The double  <DELIM>  (echoed  as
                         ``)  terminates the command string and causes
                         the string to be  executed.   Note  that  the
                         <DELIM>  which  terminates the EW command may
                         be one of the two <DELIM>s  which  terminates
                         the command string.


     You do not need to specify an output file if  you  only  want  to
     examine  an  input  file,  without  making  permanent  changes or
     corrections.  In this case, the contents of the input file may be
     read  into  the  text  buffer  page  by  page and examined at the
     terminal.  Since all output is printed on the user  terminal,  no
     output file is needed.

     Standard TECO                                             PAGE 13
     File Selection Commands


     1.3.4 Closing Files (EX command)

     When you are finished editing a file, use the EX command to close
     out  the  file  and  exit from TECO.  The current contents of the
     text buffer and any portion of the input file that has  not  been
     read yet are copied to the output file before TECO exits.  The EX
     command takes no arguments.


     COMMAND             FUNCTION

     EX                  Write the text buffer to the  current  output
                         file, move the remainder of the current input
                         file to the current output  file,  close  the
                         output  file,  then  return  to the operating
                         system.

     ERFILE.MAC`EWCOPY.MAC`EX``
                         Open an  input  file  FILE.MAC  and  open  an
                         output file named COPY.MAC, then copy all the
                         text in the input file to  the  output  file,
                         close the output file, and exit from TECO.

     Standard TECO                                             PAGE 14
     Input and Output Commands


     1.4 INPUT AND OUTPUT COMMANDS

     The following commands permit pages of text to be read  into  the
     TECO  text  buffer  from an input file or written from the buffer
     onto an output file.  Once a page of text has been  written  onto
     the  output  file,  it  cannot  be  recalled into the text buffer
     unless the output file is closed and reopened as an input file.


     COMMAND      FUNCTION

     Y       Clear the text buffer, then read the  next  page  of  the
             input  file  into the buffer.  Since the Y command causes
             the contents of the text buffer to be  lost,  it  is  not
             permitted  if an output file is open and there is text in
             the buffer.

     P       Write the contents of the text buffer onto the next  page
             of  the  output  file, then clear the buffer and read the
             next page of the input file into the buffer.

     nP      Execute the P command n times.  If n is not specified,  a
             value of 1 is assumed.

     After each Y, P, or nP command, TECO positions the pointer before
     the first character in the buffer.

     Standard TECO                                             PAGE 15
     Pointer Positioning Commands


     1.5 POINTER POSITIONING COMMANDS

     The buffer pointer provides the means of specifying the  location
     within  a  block  of  text  at  which  insertions,  deletions  or
     corrections are to be made.  The following  commands  permit  the
     buffer pointer to be moved to a position between any two adjacent
     characters in the buffer.


     COMMAND      FUNCTION

     J       Move the pointer to the beginning of the buffer.

     L       Move the pointer forward to a position between  the  next
             line feed and the first character of the next line.  That
             is, advance the pointer to  the  beginning  of  the  next
             line.

     nL      Execute the L command  n  times,  where  n  is  a  signed
             integer.   A positive value of n moves the pointer to the
             beginning of the nth line following the  current  pointer
             position.   A negative value moves the pointer backward n
             lines and positions it at the beginnning of the nth  line
             preceding  the  current  position.   If  n  is  zero, the
             pointer is moved to the beginning of the line on which it
             is currently positioned.

     C       Advance the pointer forward across one character.

     nC      Execute the C command  n  times,  where  n  is  a  signed
             integer.  A positive value of n moves the pointer forward
             across n characters.  A negative value  of  n  moves  the
             pointer  backward across n characters.  If n is zero, the
             pointer position is not changed.  Remember that there are
             two characters, <CR> and <LF>, at the end of each line in
             the buffer.

     These commands may be used to move the buffer pointer across  any
     number of lines or characters in either direction;  however, they
     will not move the pointer across a page boundary.  If a C command
     attempts to move the pointer backward beyond the beginning of the
     buffer or forward past the end of the buffer, an error message is
     printed and the command is ignored.

     If an L command attempts to exceed the page  boundaries  in  this
     manner,  the  pointer  is  positioned at the boundary which would
     have been exceeded.  Thus, in a page of 2000 lines,  the  command
     "-4000L" would position the pointer before the first character in
     the buffer.  The command "4000L" would position the pointer after
     the last character in the buffer.  No error message is printed in
     either case.

     Standard TECO                                             PAGE 16
     Type Out Commands


     1.6 TYPE OUT COMMANDS

     The following commands permit sections of the text in the  buffer
     to  be  printed  out  on  your  terminal  for examination.  These
     commands do not move the buffer pointer.


     COMMAND      FUNCTION

     T       Type the contents of the text  buffer  from  the  current
             position  of  the  pointer through and including the next
             line feed character.

     nT      Type n lines, where n is a signed  integer.   A  positive
             value of n causes the n lines following the pointer to be
             typed.   A  negative  value  of  n  causes  the  n  lines
             preceding  the  pointer  to  be typed.  If n is zero, the
             contents of the buffer from the beginning of the line  on
             which  the pointer is located up to the pointer is typed.
             This is useful for verifying the location of  the  buffer
             pointer.

     HT      Type the entire contents of the text buffer.

     V       Type the current line.  Equivalent to the sequence "0TT".

     Standard TECO                                             PAGE 17
     Type Out Commands


     1.6.1 Immediate Inspection Commands [not in TECO-10]

     In addition, there are available as a  convenience  abbreviations
     of two frequently used type out commands.  Each one consists of a
     single character, and must be  the  very  first  character  typed
     after TECO prints its prompting asterisk.  Each of these commands
     takes effect immediately;  there is no  need  to  follow  any  of
     these  commands by any <DELIM> character.  For this reason, these
     commands are known as "immediate" commands  (see  Chapter  4  for
     more information on immediate commands).


     COMMAND      FUNCTION

     <LF>    Immediately execute  an  LT  command.   This  command  is
             issued by typing the line feed key as the first keystroke
             after TECO's prompt.  It causes TECO to move the  pointer
             ahead  one  line  and  then  type  out  the new line.  On
             terminals without a line feed key,  typing  <CTRL/J>  has
             the same effect.  (See also the next command.)

     <DELIM> Immediately execute an LT command.  (Action identical  to
             that  of  the  command  above.) This command is available
             when an ESCape surrogate is active, and  causes  TECO  to
             move the pointer ahead one line and then type out the new
             line when a <DELIM> is the first thing typed after TECO's
             prompting asterisk.
             [RSTS/E only]

     <BS>    Immediately execute  a  -LT  command.   This  command  is
             issued by typing the backspace key as the first keystroke
             after TECO's prompt.  It causes TECO to move the  pointer
             back  one  line and then type the line just moved over on
             the terminal.  On  terminals  without  a  backspace  key,
             typing <CTRL/H> has the same effect.



     These commands are useful for "walking through" a file, examining
     and/or modifying lines one at a time.

     Standard TECO                                             PAGE 18
     Text Modification Commands


     1.7 TEXT MODIFICATION COMMANDS

     You can insert or delete text from the buffer using the following
     commands:


     COMMAND      FUNCTION

     Itext`  Where "text" is a string of ASCII  characters  terminated
             by  a  <DELIM> character.  The specified text is inserted
             into the buffer at the current position of  the  pointer.
             The  pointer  is  positioned  immediately  after the last
             character of the insertion.

     K       Delete the contents of the text buffer from  the  current
             position of the pointer up to and including the next line
             feed character.

     nK      Execute the K command  n  times,  where  n  is  a  signed
             integer.   A  positive  value  of  n  causes  the n lines
             following the pointer to be deleted.  A negative value of
             n causes the n lines preceding the pointer to be deleted.
             If n is  zero,  the  contents  of  the  buffer  from  the
             beginning  of the line on which the pointer is located up
             to the pointer is deleted.

     HK      Delete the entire contents of the text buffer.

     D       Delete the character following the buffer pointer.

     nD      Execute the D command  n  times,  where  n  is  a  signed
             integer.   A  positive value of n causes the n characters
             following the pointer to be deleted.  A negative value of
             n  causes  the  n  characters preceding the pointer to be
             deleted.  If n is zero, the command is ignored.

     Like the L and C commands, the K and D commands may  not  execute
     across  page  boundaries.  If a K command attempts to delete text
     up to and across the beginning or end of the buffer, text will be
     deleted  only  up  to the buffer boundary and the pointer will be
     positioned at the boundary.  No error message is  printed.   A  D
     command  attempting  to  delete text past the end or beginning of
     the text buffer will produce an error  message  and  the  command
     will be ignored.

     Standard TECO                                             PAGE 19
     Search Commands


     1.8 SEARCH COMMANDS

     The following commands may be used to search the input file for a
     specified string of characters.


     COMMAND      FUNCTION

     Stext`  Where "text" is a string of ASCII  characters  terminated
             by  a  <DELIM> character.  This command searches the text
             buffer for the next occurrence of the specified character
             string  following  the  current pointer position.  If the
             string is found, the pointer is positioned after the last
             character on the string.  If it is not found, the pointer
             is positioned immediately before the first  character  in
             the buffer and an error message is printed.

     Ntext`  Performs the same function as the S command  except  that
             the  search  is  continued  across  page  boundaries,  if
             necessary, until the character string is found or the end
             of  the  input  file is reached.  If the end of the input
             file  is  reached,  an  error  message  is  printed.   On
             VAX/VMS,  you  can  "back  up" into the file and continue
             editing, although doing  so  uses  TECO  features  beyond
             those  introduced  in  this  chapter.   Using  only basic
             features (or a TECO implementation other  than  VAX/VMS),
             you  must close the output file and reopen it as an input
             file before you can edit the file further.

     Both the S command and the N  command  begin  searching  for  the
     specified  character  string  at  the  current  position  of  the
     pointer.  Therefore, neither command will locate  any  occurrence
     of  the  character  string  which  precedes  the  current pointer
     position, nor will it locate any character string which is  split
     across a page boundary.

     Both commands execute the  search  by  attempting  to  match  the
     command  argument,  character for character, with some portion of
     the buffer contents.  If an N command  reaches  the  end  of  the
     buffer  without  finding  a match for its argument, it writes the
     contents of the buffer onto the output file, clears  the  buffer,
     reads  the  next  page  of  the  input  file into the buffer, and
     continues the search.

     Standard TECO                                             PAGE 20
     Sample Editing Job


     1.9 SAMPLE EDITING JOB

     The following sample editing job is included to help the new user
     to  achieve  a  greater understanding of the basic TECO commands.
     The entire terminal output from the  editing  run  is  reproduced
     intact,  with  numbers  added in the left margin referring to the
     explanatory paragraphs which follow.




     1< *EWDT1:FILE1.TXT``
     2< *HKIMR. JOHN P. JONES
      ! COMPUTER ELECTRONICS CORPORATION
      ! BOSTON, MASAASACHUSETTS
      !
      ! DEAR MR. JONES:
      !
      ! I WAS PLEASED TO RECEIVE YOUR REQUEST FOR INFORMATION
      ! PERTAINING TO THE NEW TECO TEXT EDITING AND CORRECTING
      ! PROGRAM.
      !
      ! ENCLOSED IS A COPY OF THE TECO USERS'S GUIDE, WHICH
      ! SHOULD ANSWER ALL OF YOUR QUESTIONS.
      !
      ! SINCERELY,
      !
      !
      !
      !
      ! ``
     3< *-20LSETTS`I 02150``
      ! *STION`2C13DIREGARDING``
     4< *SGUIDE`-5DIMANUAL``
      ! *SELY`0T``
      ! SINCERELY*0KIVERY TRULY YOURS``
      ! *HT``
      ! MR. JOHN P. JONES
      ! COMPUTER ELECTRONICS CORPORATION
      ! BOSTON, MASSACHUSETTS 02150
      !
      ! DEAR MR. JONES:
      !
      ! I WAS PLEASED TO RECEIVE YOUR REQUEST FOR INFORMATION
      ! REGARDING THE NEW TECO TEXT EDITING AND CORRECTING
      ! PROGRAM.
      !
      ! ENCLOSED IS A COPY OF THE TECO USER'S MANUAL, WHICH
      ! SHOULD ANSWER ALL OF YOUR QUESTIONS.
      !
      ! VERY TRULY YOURS,
      !
      !

     Standard TECO                                             PAGE 21
     Sample Editing Job


      !
      !
      !
     5< *EX``
      ! (TECO is rerun, operating system dependent)
      ! *ERDT1:FILE1.TXT`EWLP:``
     6< *Y5KIMR. JAMES B. SMITH
      ! DATEK ASSOCIATES, INC.
      ! 122 MAIN STREET WEST
      ! AUSTIN, TEXAS
      !
      ! DEAR MR. SMITH:
      ! ``
      ! *HT``
      ! MR. JAMES B. SMITH
      ! DATEK ASSOCIATES, INC.
      ! 122 MAIN STREET WEST
      ! AUSTIN, TEXAS
      !
      ! DEAR MR. SMITH:
      !
      ! I WAS PLEASED TO RECEIVE YOUR REQUEST FOR INFORMATION
      ! REGARDING THE NEW TECO TEXT EDITING AND CORRECTING
      ! PROGRAM.
      !
      ! ENCLOSED IS A COPY OF THE TECO USER'S MANUAL, WHICH
      ! SHOULD ANSWER ALL OF YOUR QUESTIONS.
      !
      ! VERY TRULY YOURS,
      !
      !
      !
      !
      !
      ! *EX``


     1) At this  point,  the  user  called  TECO  into  memory.   TECO
     responded  by  printing an asterisk at the left margin.  The user
     then entered  an  EW  command,  opening  an  output  file  called
     "FILE1.TXT" on DT1.  There is no input file.  Upon receipt of the
     double <DELIM> (echoed as ``), TECO created the designated output
     file, then printed another asterisk at the left margin.

     2) The user entered a command string consisting of two  commands.
     The  HK  command  cleared  the text buffer (not really necessary,
     since it was already empty), and the I command inserted 18  lines
     of  text into the buffer, including 8 blank lines.  TECO executed
     these commands upon receipt of the  second  double  <DELIM>.   At
     this  point,  the buffer pointer was positioned at the end of the
     buffer, following the last line feed character in the text.  Note
     that   the   user   made   an   error   while   typing  the  word
     "MASSACHUSETTS".  He typed "MASA", then realized his mistake  and

     Standard TECO                                             PAGE 22
     Sample Editing Job


     struck the DELETE key once to delete the second "A".  TECO echoed
     the deleted character.  The user then typed the correct character
     and continued the insertion.

     3) The user typed -20L to move the pointer to  the  beginning  of
     the  buffer  and SETTS` to position the pointer immediately after
     the  character  string  "ETTS"   (which   terminates   the   word
     "MASSACHUSETTS").   He then used an I command to insert one space
     and a five-digit zip code.  A second  S  command  positioned  the
     pointer  after  the word "INFORMATION".  The 2C command moved the
     pointer to the beginning of the next line  (carriage  return  and
     line  feed  count two characters), and the user deleted the words
     "PERTAINING TO" and replaced them with the word "REGARDING".

     4) The user continued editing by positioning  the  pointer  after
     the  word  "GUIDE".   He  then deleted this word, and replaced it
     with the word  "MANUAL".   Finally,  he  searched  for  the  word
     "SINCERELY", typed 0T to determine that the pointer was correctly
     positioned between the Y and the  comma  which  follows  it,  and
     typed  0K  to delete everything on the line except the comma.  He
     then  inserted  "VERY  TRULY  YOURS"  in  place   of   the   word
     "SINCERELY".   An HT command caused the edited text to be printed
     at the terminal.

     5) The command string EX`` caused the contents of the  buffer  to
     be written onto the output file and the output file to be closed.
     The user then reentered TECO and reopened the file "FILE1.TXT" as
     an input file and specified the line printer as an output file.

     6) This command  string  reads  the  first  (and  only)  page  of
     "FILE1.TXT"  into the buffer, deleted the first 5 lines, replaced
     them with a different address and salutation,  then  printed  the
     contents  of  the  buffer  on  the  terminal for verification and
     finally printed the new version  of  the  letter  onto  the  line
     printer.   Note  that  the  previous  version of the letter still
     resides in file "FILE1.TXT" on DT1.

     Standard TECO                                             PAGE 23
     Interlude


                                 INTERLUDE

     The rest of this manual is a  description  of  TECO  in  all  its
     glory.  TECO is a complex editor and has many features because it
     has been under development for a long time.  (TECO is older  than
     some  of  the  readers  of this manual!) Do not try to understand
     everything the first time through.  If you find that what you are
     reading  seems  hopelessly obscure, or makes no sense whatsoever,
     skip to the next section and come back to it some time later.  It
     will be a while before you need all of TECO's features.

     This manual is meant to be a reference manual and not a tutorial.
     Readers  who  are  first  learning  TECO  may wish to consult the
     following document (available from Digital Equipment Corporation)
     for more basic material:  DEC-10-UTECA-A-D INTRODUCTION TO TECO.

     The commands described in this manual are  those  implemented  in
     TECO-11  Version  40,  TECO-8  Version  7, and TECO-10 Version 3.
     Some of the more obscure commands may not be present  under  some
     operating  systems,  in which case this is indicated by a note in
     the form [Not in TECO-x].

     This manual also describes some (but not necessarily all) of  the
     obscure  commands  that  belong to one implementation of TECO but
     not to the other implementations.  Such commands are flagged by a
     note  of  the  form  [TECO-x only].  These commands are not to be
     considered part of the so-called "Standard TECO" and  should  not
     be  used  in  applications  that may be run on multiple operating
     systems.  Consult also the appendices for commands that are  very
     operating system dependent.

     Standard TECO                                             PAGE 24
     Invoking TECO


                                 CHAPTER 2


                               INVOKING TECO


     2.1 RUNNING TECO

     To run TECO with no special options or  defaults,  use  the  same
     command  on  your  operating system that you would use to run any
     other program.  The command is system dependent  but  is  usually
     something like

                                 RUN TECO

     Consult the  appendix  that  describes  your  operating  system's
     characteristics for details.


     2.2 CREATING A NEW FILE

     As described in Chapter 1, most operating systems  use  the  same
     command to invoke TECO for the purpose of creating a new file:

                               MAKE filespec

     The "MAKE filespec" command takes as its single argument the file
     specification   for   the   file   to   be  created.   This  file
     specification must  conform  to  the  conventions  used  by  your
     operating  system.   If  a file by that name already exists, TECO
     will give  you  a  warning  message  telling  you  that  you  are
     superseding an existing file.

     The  MAKE  command  invokes  TECO  and  performs   an   effective
     EWfilespec`` command, as described in Chapter 1.


     2.3 EDITING AN EXISTING FILE

     As Chapter 1 states, most operating systems use the same  command
     to invoke TECO for the purpose of editing an existing file:

                               TECO filespec

     The "TECO filespec"  command  takes  as  its  argument  the  file
     specification for the file to be edited.  The file will be opened
     for input and output, with back-up protection.  That  means  that
     the  system will save the original version of the source file (in
     case you 'blow' the edit).  If  your  operating  system  supports
     file  version  numbers,  a  new version will be created.  If your
     operating system does  not  support  file  version  numbers,  the
     original  file will be preserved in a file with the same name but
     with a backup extension (.BAK).

     Standard TECO                                             PAGE 25
     Editing an Existing File


     The  TECO  command  invokes  TECO  and  performs   an   effective
     EBfilespec`Y``  command.  Note that the first page of the file is
     brought  into  memory  and  that  the  text  buffer  pointer   is
     positioned at the start of the file.

     If, at any time during the edit, you discover that  the  edit  is
     invalid,  slowly  (so  TECO  can  respond  to  them)  type enough
     <CTRL/C>s to get you back to the operating system.  You will find
     that your original file has been preserved.

     TECO remembers the filespec given in a MAKE or TECO command.   If
     TECO  is  invoked  with  the command "TECO", with no filespec, it
     will open the file edited last (i.e., the remembered filespec).


     2.4 SWITCHES ON TECO and MAKE COMMANDS

     The TECO and MAKE commands can take switches (qualifiers) of  the
     form /SWITCH.  These switches are described below.


                         SWITCHES ON COMMAND LINES

     System    Switch         Meaning

     RSTS/E    /SIZE:n        start with nK word editing area
               /SIZE:+n       start  with  nK  additional   words   of
                              editing area

     RSTS/E
     RSX-11
     VAX/VMS   /INSPECT       Do not create an output file
               /FIND          Initially  position  to   the   position
                              marker  left  in  the file by the VTEDIT
                              macro and delete the marker.
               /NOCREATE      Do not automatically create a  new  file
                              if   the  file  specified  by  the  TECO
                              command does not exist.
               /NOINI         Do   not   use   TECO.INI   to   perform
                              initialization
               /NOMEMORY      Do not  remember  the  argument  to  the
                              invocation command.
               /SCROLL        Automatically   enter    split    screen
                              scrolling   mode,   using   1/4  of  the
                              screen's lines  as  the  scrolling  area
                              (available on VT100 terminals only).
               /VTEDIT        Load VTEDIT video terminal editor

     The /SCROLL switch may take a value of the following form:

               /SCROLL:n      Enter split screen scrolling mode, using
                              n lines for the scrolling area.

     Standard TECO                                             PAGE 26
     Switches on TECO and MAKE Commands


     The /VTEDIT switch may also take values (of the form :value).

               /VTEDIT:HOLD   Start up in hold screen mode
               /VTEDIT:SEEALL Start up in SEEALL mode

     These values can be combined, viz.:  /VTEDIT:HOLD:SEEALL.


     2.5 INVOKING A TECO PROGRAM

     All operating systems except TOPS-10 and  TOPS-20  use  the  same
     command  to let you start up execution of a TECO program (macro).
     This is the MUNG command.

     The MUNG command has the form

                               MUNG filespec

     where filespec is the name of the TECO program that is to be run.
     If  no  file extension (file type) is specified, .TEC is assumed.
     This command executes the  TECO  code  that  appears  within  the
     specified  file.   It  invokes  TECO  and  performs  an effective
     EIfilespec`` command (consult the appendices for operating-system
     dependent  differences).   The  contents  of  the  specified file
     should generally end with a double ESCAPE so that execution  will
     start immediately.

     Another form of this command is

                            MUNG filespec,data

     where "data" is any string of ASCII characters to  be  passed  to
     the  TECO program.  This version of the MUNG command invokes TECO
     and issues an effective

                            Idata`EIfilespec``

     command.  Under TECO-11, a space, tab, or a slash (/) may be used
     instead of the comma.

     Standard TECO                                             PAGE 27
     Invoking a TECO Program


     2.6 USER INITIALIZATION

     You can specify initialization commands to  TECO  by  creating  a
     file  called  TECO.INI.   If,  upon  start-up,  TECO finds a file
     called TECO.INI in your area, TECO executes the commands in  that
     file.   You  can  use  TECO.INI commands to set initial values of
     flags and to tailor TECO to your needs.  You  must,  however,  be
     very  careful  in  constructing  code for your TECO.INI file:  an
     error in this code may keep TECO from running at all!

     If you include unusual commands in your initialization file,  you
     would  be  prudent to surround such commands with the ?  command.
     This causes TECO to type the commands out when they are  executed
     (see  section  5.18.4).   You  should  also  print an informative
     message on the terminal reminding other users that  this  version
     of TECO has been customized.

     Example 1:

                                   ?1ED?

     The user initialization file sets the ED flag  to  1  so  that  ^
     characters  in  search strings have their traditional meaning (do
     not convert the next character to a control character).  The file
     also causes the command to be typed out when it is executed.

     Example 2:

     0,16ED ^A[Dot preserved on failing searches]^A 13^T 10^T

     The user initialization file causes future search string failures
     to  preserve  the  pointer  position.   It  also prints a message
     informing all users of this feature.

     Standard TECO                                             PAGE 28
     User Initialization


     In TECO-11, the TECO.INI commands  may  return  a  value  to  the
     command processor.  Such a value, if present, is interpreted as a
     set of bit encoded flags that  control  the  startup  processing.
     The following bits may be set:

               Value&1   Automatically load the VTEDIT  macro  (as  if
                         the user had typed TECO/VTEDIT).

               Value&4   Inhibit use of the memory  file  (as  if  the
                         user had typed TECO/NOMEMORY).

               Value&16  Automatically load VTEDIT  and  start  it  in
                         SEEALL   mode  (as  if  the  user  had  typed
                         TECO/VTEDIT:SEEALL).

               Value&32  Automatically load VTEDIT  and  start  it  in
                         HOLDSCREEN  mode  (as  if  the user had typed
                         TECO/VTEDIT:HOLD).

               Value&128 Automatically enter  split  screen  scrolling
                         mode (as if the user had typed TECO/SCROLL).

               Value&256 Inhibit automatic creation of the output file
                         if  the  input file does not exist (as if the
                         user had typed TECO/NOCREATE).

     For  additional  information  on  initialization,   consult   the
     operating system specific appendices.

     Standard TECO                                             PAGE 29
     Conventions and Structures


                                 CHAPTER 3

                        CONVENTIONS AND STRUCTURES


     3.1 TECO CHARACTER SET

     TECO accepts the full 8-bit ASCII character set.  (In other  than
     TECO-11,  characters  typed  at  the  console  have their 8th bit
     trimmed off.  If your terminal does not transmit or  receive  all
     of  the  ASCII codes, you can still insert the full character set
     into your TECO buffer, using special commands (see section 5.6).

     For more information  on  TECO's  handling  of  8-bit  characters
     (including  on  terminals capable of displaying only 7-bit data),
     see the description of the 4096 ET bit, in section 5.16.

     When TECO is maintaining a window into the text buffer, a special
     facility  (called  "SEEALL"  or  "View All" mode) is available to
     explicitly show certain characters which normally do  not  print,
     such  as  <CR>,  <FF>, and <TAB>.  This mode is controlled by the
     3:W flag, which is described in section 5.17.

     TECO command strings may be entered using upper  case  characters
     (as  shown throughout this manual) or lower case characters.  For
     example,  the  commands  MQ,  mQ,  Mq,  and   mq   are   executed
     identically.   A file containing upper and lower case text can be
     edited in the same way as a  file  containing  upper  case  only,
     although  this  may  be  clumsy  to  do  from  an upper case only
     terminal.  TECO can be set to convert lower case  alphabetics  to
     upper  case  as they are typed in;  commands to enable or disable
     lower case type-in will be presented in section 5.16.

     Control characters are generally echoed by TECO  as  a  caret  or
     up-arrow  followed  by  the  character.  Some control characters,
     such as <CTRL/L> (form feed) and  <CTRL/G>  (bell)  echo  as  the
     function  they  perform.   In  many cases, you can type a control
     character as a caret (up-arrow) followed by a character,  and  it
     will be treated as if it had been entered using the control key.

     There are exceptions to the interchangeable use  of  the  CONTROL
     key  and  the  caret.   When  a  control character is used as the
     delimiter of a text string (as explained in Section 3.2.2 below),
     it  must be entered in its <CTRL/x> form.  This form must also be
     used if the control  character  is  the  second  character  of  a
     two-character  command,  or  is  being  entered  as an immmediate
     action command.  Since certain control  characters  have  special
     meaning  in  text  arguments,  some of them (such as <CTRL/N> and
     <CTRL/X>), must be entered into a text string using  the  CONTROL
     key and preceded by <CTRL/Q>, ^Q, <CTRL/R>, or ^R.

     Standard TECO                                             PAGE 30
     Conventions and Structures


     3.2 TECO COMMAND FORMAT

     Each TECO commands consists of one or two characters.

     TECO commands  may  be  strung  together  (concatenated)  into  a
     command  string.   If  a  command  in  the string returns numeric
     value(s), it or they will be passed to the following command.


                                   NOTE

         Most commands which return a value are expressly designed
         for that purpose.  A few commands (such as n%q and m,n:W,
         q.v.) can be used to cause an action, and also  return  a
         value.  Good programming practice suggests following such
         a command with <DELIM> or caret-[ if the  returned  value
         is not intended to affect the following command.


     A TECO command may be preceded by one or two  numeric  arguments.
     Some TECO commands may be followed by a text argument.  Many TECO
     commands can be modified by "@" (see section 3.2.2) and/or by ":"
     (see section 3.2.3).

     When TECO commands are concatenated into  a  command  string,  no
     delimiter  is necessary between commands except for one necessary
     to delimit a text argument or one as suggested in the note above.

     TECO commands are accumulated into a command string as  they  are
     typed.   The  command string is executed when it is terminated by
     typing two consecutive <DELIM> characters.   TECO  then  executes
     the  commands  in  the  order in which they appear in the command
     string, until the string is exhausted or an error occurrs.  (Some
     TECO  commands  cause branching or looping, so altering the order
     of execution.)

     TECO's <DELIM> character is (internally) the ESCape  (octal  33).
     Because  newer  terminals  use  the  ESCape  character as part of
     control sequences (and some terminals no longer even  possess  an
     ESCape key), provision is made for you to designate a key on your
     terminal to cause an ESCape to be sent to TECO -- that is, to act
     as  an  ESCape  surrogate.  (See the EE flag and the 8192 ET bit,
     section 5.16.) Because the key you press to delimit text  strings
     and  TECO commands may be the ESCape key or may be the surrogate,
     this manual uses the indirect term <DELIM> to mean whichever  one
     you are using.  When an ESCape surrogate is active, the character
     you see is `.  (When no surrogate is active,  you  see  $.)  This
     manual uses the ` character.

     Standard TECO                                             PAGE 31
     Conventions and Structures


     3.2.1 Numeric Arguments

     Most TECO commands may be preceded by a numeric  argument.   Some
     numeric  arguments  must  be positive;  others can be negative or
     zero.  The maximum size of any numeric argument is restricted, as
     summarized in the following table:

     				  Signed	       Unsigned
     		System	      Min	  Max		 Max
     		TECO-8	    -2**12+1	+2**12-1	2**13-1
     		TECO-10	    -2**34	+2**34-1	2**35-1
     		TECO-11	    -2**15	+2**15-1	2**16-1

               TABLE 3-1  Restrictions on numeric arguments

     Exceeding these ranges of values can cause unpredictable results.
     So  can  using a negative argument with a command that takes only
     an unsigned argument.

     Numeric arguments can be used in the following ways:

             - Character commands such as J, C, R, and D take a single
               numeric   argument   which  represents  the  number  of
               characters that the command is to act on.

             - Such commands as P, PW, and < perform  an  action  that
               can   be   repeated.    The  numeric  argument  is  the
               repetition count.

             - Some commands, such as ED, ET, ^E, ^X, ES, EU, and  EV,
               control  the setting of variables called flags.  When a
               numeric  argument  is  specified,  the  value  of  that
               argument  becomes the new value of the associated flag.
               When no numeric argument is  specified,  these  command
               return the value of the associated flag.

             - Line commands such as T, K, X, FB, and  FC  operate  on
               lines.   They take zero, one, or two numeric arguments.
               If one argument (n) is  specified,  it  represents  the
               number  of  lines  over  which  the  command is to have
               effect,  beginning  at  the  current   buffer   pointer
               position.   A  positive  (non-zero)  n  affects  a text
               running from the current pointer position  to  the  nth
               following  line delimiter.  A negative n affects a text
               running from the pointer back to the beginning  of  the
               line  containing the nth previous line delimiter.  When
               n is zero, the affected text runs from the beginning of
               the current line to the current pointer position.  When
               n is omitted, n = 1 is assumed.

               When a line  command  contains  two  numeric  arguments
               (m,n),  these  represent  the pointer positions between
               which text is affected.  Unless the description of  the

     Standard TECO                                             PAGE 32
     Conventions and Structures


               command  says  the  order  of  these  two  arguments is
               important, they may be entered in either order.

     When a command that normally takes an argument is specified  with
     no argument, TECO executes the command in the most common or most
     useful way, as shown in the following table:

     	Command   Default Argument	Default Action

     	C		1		Advance 1 character
     	R		1		Back over 1 character
     	L		1		Advance 1 line
     	J		0		Jump to start of buffer
     	V		1		View 1 line
     	D		1		Delete 1 character
     	K		1		Kill 1 line
     	S, N, etc.	1		Search for first occurrence
     	%		1		Increment Q-register by 1
     	X		1		Extract one line

                       Table 3-2  Default Arguments

     These default arguments reduce the number  of  keystrokes  needed
     for common TECO actions.


     3.2.2 Text Arguments

     Many TECO commands take a text (character string) argument.   The
     string  is placed immediately after the command and consists of a
     sequence of ASCII characters terminated by  a  <DELIM>  character
     (or in the case of !  and ^A commands, by the command character).
     The string of ASCII characters may not include a  <DELIM>,  since
     this  would terminate the string prematurely, but may include any
     other character.  (Some characters may be difficult to enter from
     a  terminal  because  they  are TECO immediate action commands or
     because they have been filtered out by the operating system).

     Examples of text arguments:

               Sabc`                    Search for the string "abc"

               ^UAHELLO`                Insert the text  "HELLO"  into
                                        Q-register A

               OBEGIN`                  Branch to the tag specified by
                                        the string "BEGIN"

     Some TECO commands require two  text  arguments.   Each  argument
     must be followed by a <DELIM> character, as follows:

               FSabc`def`               Replace string "abc" by "def"

     Standard TECO                                             PAGE 33
     Conventions and Structures


     You can include a <DELIM> character in a  text  string  by  using
     another  format  of  text  argument.  In this alternate form, the
     string is delimited on both sides by any ASCII code that does not
     otherwise  appear  in the string.  You signal that this format is
     being used by inserting an @ character  before  the  command,  as
     follows:

               @ER5TEST.FOR5            Open the file  "TEST.FOR"  for
                                        input.   The delimiter used is
                                        "5"

               @^A+Hello out there!+    Type the  message  "Hello  out
                                        there!"  on the terminal.  The
                                        delimiter is "+"

     Unpredictable  results  will  occur  if  another   TECO   command
     intervenes  between an @ sign and the command that it is supposed
     to affect.  Note that a control character  used  as  a  delimiter
     must  be  entered  as  <CTRL/x> (that is, in its single-keystroke
     form).



     3.2.3 Colon Modifiers

     The colon (:) command modifies the action of  the  next  command.
     In  some  cases, it will cause the next command to return a value
     indicating whether it  has  failed  or  succeeded.   A  zero  (0)
     indicates  that the command has failed, while a -1 indicates that
     it has succeeded.  The colon modifier is used this way with  such
     commands  as  :ER,  :EB, :EN, :S, :N, :FS, :FN, :FB, and :FC.  If
     the next sequential command requires a positive argument, the  -1
     is interpreted as the largest possible positive number.  In other
     cases, such as :Gq and :=, the colon modifier changes the meaning
     of  the  command.  Unpredictable results may occur if you place a
     colon directly before a  TECO  command  that  does  not  normally
     accept a colon modifier.

     If both the :  and the @ (string delimiter)  are  used  with  the
     same command, they may be placed in either order.

     Standard TECO                                             PAGE 34
     Conventions and Structures


     3.3 DATA STRUCTURES

     A good way to begin the study of a  programming  language  is  to
     forget  the  commands, for the moment, and concentrate instead on
     the  data  structures.   This  section  follows  that   approach,
     describing both the values on which TECO operates and the buffers
     and registers in which these values are stored.

     TECO manipulates two types of data, namely,

         o  The character string:  a sequence of zero  or  more  ASCII
            characters, and

         o  The integer:  a  numeric  value  that  may  be  signed  or
            unsigned.


     The text that TECO edits is, of course, a character string.  Less
     obviously,  the command string by which the user controls TECO is
     also a character string.  The counters and indices for  character
     string  manipulation,  and  the  repetition  counts for loops are
     integers.

     Character   strings   and   integers   have   distinct   internal
     representation  and  this  is reflected in the design of the TECO
     commands.  Commands designed for character strings do not work on
     integers and vice versa.

     The data structures described  in  this  section  are  frequently
     applied  to  character  strings.  Structure is never "built into"
     the data, but rather is attributed  to  the  data  by  particular
     commands   and  conventions.   Thus  "lines"  of  characters  are
     recognized by line manipulation commands, but  not  by  character
     manipulation  commands,  which  view  an end-of-line character as
     just another ASCII code.

     The following are definitions for the line and the page in TECO:

         o  Any character string can be divided  into  TECO  lines  by
            considering the line to be ended by either

                 a line feed (octal 12)
                 a form feed (octal 14)
                 a vertical tab (octal 13) or
                 the end of the given character string

         o  Any character string can be divided  into  TECO  pages  by
            considering the page to be ended by either

                 a form feed (octal 14) or
                 the end of the given character string

     Standard TECO                                             PAGE 35
     Conventions and Structures


     These data structures are used  to  achieve  two  quite  separate
     results:   the formatting of type out and the logical division of
     data.


     3.3.1 Text Buffer

     The main storage of TECO is the text  buffer.   The  text  buffer
     stores  a single character string that TECO edits.  A text buffer
     pointer is used to address text in the buffer;  it is moved about
     by  many  TECO commands.  The text buffer pointer never points to
     characters in the buffer;   it  is  always  pointing  at  pointer
     positions  (between characters).  The available pointer positions
     in the text buffer are sequentially numbered  beginning  with  0.
     Pointer  position  0  is the position at the start of the buffer,
     just to the left of the first character.  Pointer position  1  is
     the next position, just to the right of the first character, etc.
     As an example,  suppose  the  text  buffer  contains  the  string
     FOOBAR.   Then seven text buffer pointer positions are determined
     as shown by the arrows in the following figure:

     		F     O     O     B     A     R
     	     |     |     |     |     |     |     |
     	     0     1     2     3     4     5     6


     Note that there are 6 characters  in  the  buffer  and  that  the
     highest  numbered  pointer  position  is 6.  The pointer position
     number is equal  to  the  number  of  characters  preceding  that
     position.

     Useful definitions of "current" objects are made with respect  to
     the text buffer pointer as follows:

          1.  The  current  character  of  the  text  buffer  is   the
              character  just  to  the  right  of the pointer.  If the
              pointer is at the end of the text buffer,  there  is  no
              character  to  the  right of the buffer pointer, and the
              current character does not exist.

          2.  The current line of the text buffer  is  the  TECO  line
              that  contains  the  current  character.  In the special
              case that the pointer is at the end of the  buffer,  the
              current  line  is everything back to (but not including)
              the last end-of-line character.

          3.  The current page of the text buffer  is  the  TECO  page
              that  contains  the  current  character.  In the special
              case that the pointer is at the end of the  buffer,  the
              current  page  is everything back to (but not including)
              the last form feed character (or the  beginning  of  the
              buffer).

     Standard TECO                                             PAGE 36
     Conventions and Structures


     When the text buffer pointer is at the end of the text buffer and
     the  last  character  of  the buffer is an end-of-line character,
     then the current  line  is  an  empty  string  according  to  the
     definition  just given.  In this case, TECO performs the required
     operation on this empty string.  For example, if the  pointer  is
     at  the  end of the buffer and TECO is commanded to kill (delete)
     the next 3 lines, then  the  empty  string  is  killed  3  times.
     Similarly, if the pointer is at the end of the buffer and TECO is
     commanded to advance the pointer 5 lines, the pointer will remain
     at  the end of the buffer.  No error message will be given.  In a
     like fashion, if the pointer is at the end of the first  line  of
     the  buffer,  and  TECO  is  instructed to extract the previous 4
     lines (into a Q-register), then only the first line is  extracted
     since it is presumed to be preceded by 3 empty lines.



     3.3.2 Q-registers

     TECO provides data storage registers, called  Q-registers,  which
     may  be  used  to  store  single  integers and/or ASCII character
     strings.  Each Q-register is divided into two storage areas.   In
     its  numeric  storage  area, each Q-register can store one signed
     integer.  In its text storage area, each Q-register can store  an
     ASCII  character  string  (which  can  be any text, including the
     important case of a TECO command string).

     There are global Q-registers and (in TECO-11) local Q-registers.

     In every TECO, there are 36 global Q-registers, each of which has
     a  one-character  name:  A through Z and 0 through 9.  The global
     Q-registers  are  available  to  all  macro   levels,   including
     "outside" macros altogether (that is, at prompt level).

     In TECO-11, there are additionally 36 local Q-registers, each  of
     which has a two-character name:  .A through .Z and .0 through .9.
     Effectively,  there  is  a  complete  and  unique  set  of  local
     Q-registers  available  to  each and every macro level, including
     prompt level.  TECO automatically  saves  and  restores  a  given
     macro  level's  local  Q-registers  around  execution of a nested
     (lower level) macro.  When a macro is invoked via an  Mq  command
     (where  the  command  is  not  colon-modified,  and q is a global
     Q-register), the current set of local Q-registers is saved and  a
     new  set of local Q-registers created.  When the macro exits, its
     local Q-registers are destroyed and those of  the  calling  macro
     level  are restored.  (If a fatal error occurs and TECO goes back
     to prompt level, local Q-registers  from  all  macro  levels  are
     destroyed and prompt level's set is restored.)

     (A new set of local Q-registers is not created when  the  command
     is  colon-modified,  as  in :MA, or when the invoked macro itself
     resides in a local Q-register, as in M.A -- see Table 5-9C.)

     Standard TECO                                             PAGE 37
     Conventions and Structures


     A local Q-register name can be used in any command that  takes  a
     Q-register name.

     Various TECO commands allow the storing and retrieving of numeric
     values  from the numeric storage areas of the Q-registers.  Other
     TECO commands allow the storage and retrieval of strings from the
     text storage areas of the Q-registers.



     3.3.3 Q-register Push-down List [not in TECO-8]

     The Q-register pushdown list is a stack that permits the  numeric
     and text storage areas of Q-registers to be saved (the [ command)
     and  restored  (the  ]  command).   The  command  sequence  [A ]B
     replicates  the  text  string and numeric value from Q-register A
     into Q-register B.  (Note that in TECO-11, macros can be  written
     to  use  local Q-registers, avoiding the need to save and restore
     Q-registers via the pushdown list.)



     3.3.4 Numeric Values and Flags

     TECO  has  many  special  numeric  values  and  flags  which  are
     accessible  through TECO commands.  Some of these values, such as
     the text buffer pointer,  reflect  the  state  of  TECO.   Others
     control TECO's behavior in various ways.

     Standard TECO                                             PAGE 38
     Command String Editing


                                 CHAPTER 4

                          COMMAND STRING EDITING


     4.1 Immediate Action Editing Characters

     While  you  are  typing  command  strings  at  a  terminal,  TECO
     considers certain ASCII characters to have special meaning.  Most
     of the special characters  cause  TECO  to  perform  a  specified
     function  immediately,  without  waiting  for  the double <DELIM>
     which  normally  be  required  to  terminate  a  command  string.
     Immediate  action  editing characters may be entered at any point
     in a command string - even in the middle of  a  command  or  text
     argument.

     Many immediate action editing characters, such as <DELETE> (which
     deletes  the  immediately preceding character), cannot be used as
     regular TECO commands.  For instance, if  you  enter  a  <DELETE>
     into  a  command string which is to be later executed as a macro,
     the <DELETE> will not delete a character as part the execution of
     the macro.

     Some characters, like <CTRL/U>, are both  regular  TECO  commands
     and  immediate  action  commands.   The  command  string ^Uqtext`
     enters the specified text into Q-register q.   However,  <CTRL/U>
     typed  while  entering  a  command  string is an immediate action
     editing character which  deletes  the  current  line.   Thus  you
     cannot  type  a  <CTRL/U> (or any similar sequence) directly into
     TECO as part of a  command  string.   Nevertheless,  <CTRL/U>  is
     still  a valid TECO command;  should TECO encounter it in a macro
     or  indirect  file,  it  will  have  its  regular   TECO   effect
     (^Uqtext`).

     Control characters used as immediate  action  editing  characters
     must  be  entered  using  the  CONTROL  key;   they  will  not be
     recognized if entered in their caret or up-arrow form.

     Table 4-1 lists  the  immediate  action  editing  characters  and
     explains their functions.

     Standard TECO                                             PAGE 39
     Command String Editing


              TABLE 4-1: IMMEDIATE ACTION EDITING CHARACTERS

     These characters take immediate effect and are  used  to  edit  a
     command string as it is being entered:

     CHARACTER      EXPLANATION

     <DELIM><DELIM>
                    The double <DELIM> character sequence  tells  TECO
                    to  begin  execution  of  the  command string just
                    typed in.   It  inserts  two  <ESCAPE>s  into  the
                    command  string.   (<DELIM>  may  be  generated by
                    pressing a  key  designated  by  the  user  as  an
                    "ESCape surrogate" or by pressing an actual ESCape
                    key.  In the former case, ``  is  echoed;   if  no
                    ESCape   surrogate  has  been  designated,  $$  is
                    echoed.  See the EE flag  and  the  8192  ET  bit,
                    section 5.16, for more information.)

                    The two <DELIM>s must be typed  successively.   If
                    any  other  character  is typed in between the two
                    <DELIM>s (even if subsequently DELETEd), then  the
                    two  <DELIM>s  might  be  treated  simply  as  two
                    <DELIM>s to be entered  into  the  command  string
                    rather than as an immediate action command.

                    If you need to enter two <DELIM>s into  a  command
                    line,  as  in  the  case where you want to use the
                    FSstring`` command to delete  a  string,  you  can
                    keep  TECO  from  recognizing  ``  as an immediate
                    action               command.                 Type
                    <DELIM><SPACE><DELETE><DELIM>  and  then  continue
                    entering the remainder of your command string.

                    A  single  <DELIM>  character  can  also   be   an
                    immediate  action  command (when typed immediately
                    after TECO's prompting asterisk, see section 4.2).
                    Elsewhere,  a single <DELIM> performs no immediate
                    action.

     <DELETE>       Typing a DELETE character (DEL or RUBOUT  on  some
                    terminals)   deletes  the  last  character  typed.
                    DELETE can be typed repeatedly to  erase  multiple
                    characters.   TECO  echoes  the  deleted character
                    whenever a DELETE is typed, indicating to you that
                    the  character  has  been  rubbed out.  If you are
                    doing your editing on a scope terminal,  then  the
                    action  of  this  key is different:  the character
                    that has been rubbed out will disappear  from  the
                    screen  of  your  editing  terminal and the cursor
                    will be moved back one position.

                    If you delete a line feed, form feed, or  vertical

     Standard TECO                                             PAGE 40
     Command String Editing


                    tab,  the  cursor  will  move  up  the  screen and
                    position itself  at  the  end  of  the  text  that
                    immediately  preceded the line feed, form feed, or
                    vertical tab.

     <CTRL/C>       <CTRL/C> echoes as ^C  (Caret-C)  and  aborts  the
                    entering  of the command string.  The exact action
                    of the  <CTRL/C>  key  depends  on  the  operating
                    system being used (See appendices).

     <CTRL/U>       <CTRL/U> causes the current line  of  the  current
                    command  line  to  be  deleted.   TECO  echoes the
                    character  as  ^U  followed  by  <CR><LF>  and  an
                    asterisk   prompt.   If  you  are  using  a  scope
                    terminal, the visible action of typing this key is
                    different.  The current line physically disappears
                    from the screen and the cursor is positioned  back
                    at the beginning of the line.

     <CTRL/G><CTRL/G>
                    Typing two consecutive <CTRL/G> characters  causes
                    all  commands  which  have  been  entered  but not
                    executed to be erased.  (If  the  terminal  has  a
                    bell, it will ring.) This command is used to erase
                    an  entire  command  string.   A  single  <CTRL/G>
                    character is not a special character.

     <CTRL/G><space>
                    <CTRL/G> followed  by  a  space  causes  the  line
                    currently being entered into the command string to
                    be retyped.

     <CTRL/G>*      <CTRL/G> followed by an asterisk  causes  all  the
                    lines  typed by the user from the last TECO prompt
                    (the asterisk) to be retyped.

     <CR>           Typing a carriage return enters a carriage  return
                    followed  by  a line feed into the command string.
                    To enter a carriage return without  a  line  feed,
                    type <CR><DELETE>.

     <CTRL/Z><CTRL/Z><CTRL/Z>
                    RSX-11 TECO uses the triple <CTRL/Z> command as an
                    immediate  action  command.   See  the appropriate
                    appendix for more details.

     The <CTRL/Z> character is used as an  end-of-file  terminator  in
     some  contexts  on some operating systems.  While its presence is
     usually harmless in disk files, it may  cause  premature  end  of
     file if the file is copied to other media (e.g., paper tape).

     Standard TECO                                             PAGE 41
     Command String Editing


     4.2 Immediate Action Commands

                   TABLE 4-2: IMMEDIATE ACTION COMMANDS

     The following commands take effect if  (and  only  if)  they  are
     typed  as  the  very  first  keystroke(s)  after  TECO issues its
     asterisk prompt.

     The <LF>, <DELIM>,  and  <BS>  commands  are  also  described  in
     Chapter  1,  where  they  are introduced as "immediate inspection
     commands".

     CHARACTER      EXPLANATION

     ?              If the previous  command  aborted  because  of  an
                    error,  this  immediate action command causes TECO
                    to print the erroneous  command  string  from  the
                    beginning  of  the  current  macro level up to and
                    including the character that caused the error.

     /              If TECO has just printed an  error  message,  type
                    this  immediate  action  command to receive a more
                    detailed explanation of the error.  (On VAX/VMS, a
                    HELP  command  is  also  available.   See  section
                    G.13.)
                    [In TECO-11, implemented only on VAX/VMS]

     <LF>           Typing this immediate action command,  line  feed,
                    as  the first keystroke after TECO's prompt causes
                    TECO to immediately execute an LT  command.   This
                    aid  lets you "walk through" a file on a non-scope
                    terminal.  (If the EV flag is non-zero, then the T
                    portion of this command is redundant and therefore
                    is not performed.) If you are  already  positioned
                    at  the  end  of the text buffer, TECO-11 will not
                    type out anything.
                    [Not in TECO-10]

     <DELIM>        Typing this immediate action command, <DELIM>,  is
                    synonymous  with  typing the <LF> immediate action
                    command  (described  above).   This   command   is
                    available on TECOs offering the ESCAPE surrogate.
                    [TECO-11 only]

     <BS>           Typing this immediate action  command,  backspace,
                    (as  the  first  keystroke  after  TECO's  prompt)
                    causes TECO to immediately execute a -LT  command.
                    (If the EV flag is non-zero, then the T portion of
                    this command is redundant  and  therefore  is  not
                    performed.)
                    [Not in TECO-10]

     ^W             Typing this immediate action command, <CTRL/W>, as

     Standard TECO                                             PAGE 42
     Command String Editing


                    the  first  keystroke  after  TECO's  prompt  when
                    split-screen scrolling is active  causes  TECO  to
                    re-paint the buffer display portion of the screen.
                    (Split-screen scrolling  is  active  when  7:W  is
                    non-zero.)  This  command is useful if the display
                    has been "confused" by characters from a broadcast
                    message  or  type-ahead.   It  is  also  useful in
                    conjunction with ED's 128 bit (which inhibits  all
                    automatic scroll display updating).
                    [TECO-11 only]

     *q             When  an  asterisk  followed  immediately   by   a
                    Q-register  name (any alphanumeric character, here
                    represented by q) is  the  first  keystroke  after
                    TECO's  prompt,  TECO  places the previous command
                    string into Q-register q.  [In TECO-8, only the *Z
                    command  is permitted, and TECO will automatically
                    type the Z.] Note  that  since  *q  is  itself  an
                    immediate  action  command,  it  may not be edited
                    with other immediate action  commands.   In  other
                    words,   you   can't   use  DELETE  to  delete  an
                    incorrectly typed *.

                    [In   TECO-10,   *q   must    be    followed    by
                    <DELIM><DELIM>.]

     Standard TECO                                             PAGE 43
     Command String Editing


     4.3 Introduction to Macros

     One of TECO's powerful features is the ability to  execute  ASCII
     text  stored in a Q-register as a command string.  This is called
     the "macro" facility, and a command string so stored and executed
     is called a "macro".

     A Q-register may be loaded with a macro by any of several  means:
     directly  from  the  console (via the ^Uq command), by extraction
     from the text buffer (via the X command), or by  these  or  other
     Q-register loading commands contained in an indirect file or even
     in another macro.

     Particularly handy is the "*" immediate action command, discussed
     in  a preceding section.  When you type this command as the first
     character following TECO's asterisk prompt, whatever  immediately
     preceding  command  you  just  typed at the console is saved in a
     Q-register.  You can then use that command again (and repeatedly)
     by using the Mq command.

     You invoke a macro by using the Mq command, where "q" is the name
     of the Q-register in which the macro text has been stored.

     A related facility is that of immediate ESCAPE-sequence commands,
     which is discussed in the following section.

     Standard TECO                                             PAGE 44
     Command String Editing


     4.4 Immediate ESCAPE-Sequence Commands [TECO-11 only]

     Certain keys on many newer terminals generate  ESCape  sequences.
     TECO  provides  a facility by which you can cause the pressing of
     one of these keys at the prompting asterisk to be interpreted  as
     an  immediate command.  When this facility is enabled, a key such
     as one of the cursor control keys can cause TECO  to  immediately
     execute  commands  (previously  stored  as  a macro).  The single
     keystroke suffices;  no <DELIM><DELIM> is needed.

     The 32 bit  in  the  ED  flag  enables  immedate  ESCape-sequence
     commands.   When ED's 32 bit is non-zero, and the first character
     TECO  receives  after  its  *  prompt  is   ESCape,   TECO   will
     automatically  read  further  characters and attempt to decode an
     ESCape sequence.  The decoded ESCape sequence is resolved into  a
     pair  of  numeric  values,  which  are  then  passed to the macro
     residing in global Q-register A.

     The two numeric values are a type code and a  value  code.   They
     are passed to the macro in QA by an effective <type>,<value>MA``.
     The macro in QA can retrieve them by code such as:
             UA                    ! Save the <value> code in QA !
             @O!T0,T1,T2,T3!       ! Dispatch on <type> code !
             !T0!                  ! Type 0 codes come here !
               QA@O!V0,V1,V2...

     The <type> and <value> codes are as follows.

     Type 0 - ESCape followed by a control character
         The <value> code is the control character's code (0 - 31.)

     Type 1 - ESCape followed by a letter (e.g., ESC A), -or-
              ESCape followed by [ then a letter (e.g., ESC [ A), -or-
              CSI    followed by a letter (e.g., CSI A), -or-
              ESCape, O, then an uppercase letter (e.g., ESC O A)
         The <value> code is the letter's ASCII value,
         trimmed to 5 bits (that is, a value of 0 through 31)
         Common keys of <type> 1 are:
              Up arrow      <type> 1    <value> 1
              Down arrow    <type> 1    <value> 2
              Left arrow    <type> 1    <value> 4
              Right arrow   <type> 1    <value> 3
              PF1           <type> 1    <value> 16
              PF2           <type> 1    <value> 17
              PF3           <type> 1    <value> 18
              PF4           <type> 1    <value> 19
              ENTER         <type> 1    <value> 13

     Standard TECO                                             PAGE 45
     Command String Editing


     Type 2 - ESCape followed by ? then a letter (e.g., ESC ? p), -or-
              ESCape, O, then an lowercase letter (e.g., ESC O p)
         The <value> code is the letter's ASCII value,
         trimmed to 5 bits (that is, a value of 0 through 31)
         Common keys of <type> 2 are:
              Keypad ,      <type> 2    <value> 12
              Keypad -      <type> 2    <value> 13
              Keypad .      <type> 2    <value> 14
              Keypad 0      <type> 2    <value> 16
              Keypad 1      <type> 2    <value> 17
              Keypad 2      <type> 2    <value> 18
              Keypad 3      <type> 2    <value> 19
              Keypad 4      <type> 2    <value> 20
              Keypad 5      <type> 2    <value> 21
              Keypad 6      <type> 2    <value> 22
              Keypad 7      <type> 2    <value> 23
              Keypad 8      <type> 2    <value> 24
              Keypad 9      <type> 2    <value> 25

     Type 3 - ESCape followed by [ then a digit string then ~ -or-
              CSI    followed by a digit string then ~
         The <value> code is the value of the digit string.
         All of the LK201 keyboard's editing and function
         keys generate sequences of this format.

     Standard TECO                                             PAGE 46
     Command String Editing


     4.5 Operating System Character Filters

     In general, TECO accepts any ASCII character, whether encountered
     in a macro, read from an indirect file, or entered directly via a
     command string from the terminal.  (Note that  TECOs  other  than
     TECO-11 strip the eighth bit on command input.) In addition, some
     operating systems  filter  out  certain  characters  typed  at  a
     terminal  and do not pass them to TECO.  So that you can be aware
     of the possible difficulty of entering these characters  directly
     into  a  TECO  command  string,  we list them below in Table 4-5.
     Note that these characters are still valid  characters  to  TECO,
     but  may  have to be entered indirectly, such as by using the nI`
     command.

          ^T Note:
               On some operating  systems,  the  ^T  character  is  an
               immediate action command (to the operating system), and
               invokes a one-line status report.

               Where reference is made below  in  Table  4-5  to  this
               note, TECO causes the operating system's recognition of
               ^T to be turned off if TECO  ever  asks  the  user  for
               input.   The  original state of ^T handling is restored
               upon exit.  MUNGed TECO macros that never ask the  user
               for input do not affect the operating system's handling
               of ^T.

     Standard TECO                                             PAGE 47
     Command String Editing


                    TABLE 4-5:  OPERATING SYSTEM CHARACTER FILTERS

     SYSTEM         CHARACTER   SYSTEM's USE

     RT-11          ^A          VT11 support [only if GT ON]
                    ^B          Background control [F/B systems only]
                    ^E          VT11 support [only if GT ON]
                    ^F          Foreground control [F/B systems only]
                    ^O          Output control
                    ^Q          Terminal Synchronization
                    ^S          Terminal Synchronization

     RSTS/E         ^O          Output control
                    ^Q          Terminal Synchronization
                    ^S          Terminal Synchronization

     VAX/VMS        ^O          Output control
                    ^Q          Terminal Synchronization
                    ^S          Terminal Synchronization
                    ^T          System status (see ^T Note above)
                    ^X          Cancel Type-ahead
                    ^Y          Process Interruption

     RSX-11         ^O          Output control
                    ^Q          Terminal synchronization
                    ^S          Terminal synchronization
                    ^X          Task control [RSX-11D only]

     TOPS-10        ^C^C        Job interruption
                    ^O          Output control
                    ^Q          Terminal synchronization
                    ^S          Terminal synchronization
                    ^T          System status

     TOPS-20        ^C^C        Job interruption
                    ^O          Output control
                    ^Q          Terminal synchronization
                    ^S          Terminal synchronization
                    ^T          System status

     OS/8           ^B          Background control [F/B systems only]
                    ^F          Foreground control [F/B systems only]
                    ^Y          Reboot indicator [F/B systems only]

     Standard TECO                                             PAGE 48
     Command Descriptions


                                 CHAPTER 5


                           COMMAND DESCRIPTIONS


     This chapter presents a detailed description  of  the  full  TECO
     command  set, functionally organized.  It assumes that the reader
     is familiar with the elementary TECO commands presented earlier.

     In the sections following, the letters "m" and "n"  are  used  in
     command  formats  to represent numerical arguments.  These may be
     either simple integers or complex expressions.   The  letter  "q"
     represents any Q-register.

     Standard TECO                                             PAGE 49
     File Selection Commands


     5.1 FILE SPECIFICATION COMMANDS

     You must specify an input file whenever you want TECO  to  accept
     text  from  any source other than the terminal.  You must specify
     an output file whenever you want to make a  permanent  change  to
     the  input file.  Input and output files are selected by means of
     file specification commands.

     File specification formats are operating system dependent and are
     fully  described  in  the operating characteristics appendices at
     the end of this manual.

     Almost  every  editing  job  begins  with  at  least   one   file
     specification  command.   Additional  file specification commands
     may  be  executed  during  an  editing  job  whenever   required;
     however,  TECO  will keep only one input file and one output file
     selected at a time.

     TECO-11 recognizes two input and two output "streams" called  the
     primary  and  secondary  streams.   The  primary input and output
     streams are initially selected when TECO is invoked.   Most  file
     selection  commands,  and  all  of  the other TECO commands (page
     manipulation, etc.), operate  on  the  currently  selected  input
     and/or output stream.

     The  following  sections  list  all  of  the  file  specification
     commands.   Unless  otherwise  noted, all of these commands leave
     the text buffer unchanged.  Examples of some  of  these  commands
     appear in Chapter 1.


     5.1.1 File Opening Commands

     The following commands are used  to  open  files  for  input  and
     output:


                 TABLE 5-1A:  FILE SPECIFICATION COMMANDS

     COMMAND             FUNCTION

     EBfilespec`    Edit Backup.  This command is recommended for most
                    editing   jobs.    It   is   used   for  files  on
                    file-structured  devices  only.   It   opens   the
                    specified file for input on the currently selected
                    input stream  and  for  output  on  the  currently
                    selected output stream.  The EB command also keeps
                    the unmodified file (the latest copy of the  input
                    file)  available  to  the  user;   details of this
                    process are system dependent (See appendices).

     ERfilespec`    Edit  Read.   Opens  a  file  for  input  on   the
                    currently selected input stream.

     Standard TECO                                             PAGE 50
     File Opening Commands


     EWfilespec`    Edit Write.   Opens  a  file  for  output  on  the
                    currently selected output stream.

     :EBfilespec`   Executes the EB command,  and  returns  a  numeric
                    value.   -1  returned indicates success:  the file
                    is open for input.  A 0  indicates  the  specified
                    file  could  not be found, and no error message is
                    generated.  Other errors (e.g.,  hardware  errors,
                    protection violations, etc.) generate messages and
                    terminate command execution as usual.

     :ERfilespec`   Executes the ER command,  and  returns  a  numeric
                    value.  See the :EB command, above.

     Standard TECO                                             PAGE 51
     File Specification Switches


     5.1.2 File Specification Switches

     Various  system-dependent  switches  (qualifiers)  of  the   form
     /SWITCH can be used with the file specification in ER, EW, and EB
     commands.   These  switches  are  listed  below.    Consult   the
     operating system specific appendices for further details.

     In addition, on some systems switches are provided for convenient
     handling  of  BASIC-PLUS  or  BASIC-PLUS-2 source files which use
     <LF> or & characters for program line continuation.  See Appendix
     J for more information.


                TABLE 5-1B: SWITCHES ON FILE SPECIFICATIONS

     System    Switch         Meaning

     OS/8      /S             Ignore end-of-file (<CTRL/Z>s) on input.
                              (SUPER TECO mode)

     RSTS/E    /B             Read and write with unfiltered 8-bit
               /n             Handle BASIC-PLUS-x line continuation
               /B+            Handle BASIC-PLUS line continuation
               /              Same as /B+
               /B2            Handle BASIC-PLUS-x line continuation
               /CLUSTERSIZE:n Specifies output file cluster size
               /MODE:n        Use non-standard open mode

     VAX/VMS,  /B2            Handle BASIC-PLUS-x line continuation
     RSX-11    /CR            Implied carriage control
               /-CR           No (internal) carriage control
               /FT            FORTRAN carriage control
               /FTN           Same as /FT
               /RW            Rewind magtape before opening file
               /SH            Open the file in shared mode
               /SHR           Same as /SH
               /STM           Stream format
               /VAR           Variable format

     TOPS-10   /APPEND        Append to existing output file (EW only)
               /ASCII         File is ASCII
               /GENLSN        Generate line sequence numbers
               /NOIN          Don't put user type-in into log file
               /NONSTD        Open DECtape in non-standard mode
               /NOOUT         Don't put TECO's type out into log  file
                              (EL only)
               /OCTAL         Read file in octal
               /PROTECT:n     Specify protection code
               /SIXBIT        Read file in pure SIXBIT
               /SUPLSN        Suppress line sequence numbers


     5.1.3 File Close and Exit Commands

     Standard TECO                                             PAGE 52
     File Close and Exit Commands


     The following commands are used to  close  files  and  exit  from
     TECO:


                      TABLE 5-1C: FILE CLOSE AND EXIT

     EC             Moves the contents of the text  buffer,  plus  the
                    remainder   of  the  current  input  file  on  the
                    currently selected input stream,  to  the  current
                    output  file  on  the  currently  selected  output
                    stream;  then closes those input and output files.
                    Control  remains  in  TECO.   EC  leaves  the text
                    buffer empty.

     EF             Closes the current output file  on  the  currently
                    selected  output  stream.  The EF command does not
                    write the current contents of the  buffer  to  the
                    file before closing it.

     EG`            Performs the same function as the EC command,  but
                    then  exits  from  TECO  and  re-executes the last
                    COMPIL class command (.COMPILE,  .LINK,  .EXECUTE,
                    etc.)
                    [Same as EX in TECO-11]

     EGtext`        Performs the same function as the EC command,  but
                    then  exits  from  TECO  and  passes "text" to the
                    operating  system  as  a  command  string  to   be
                    executed (see appendices).

     :EGcmd args`   Performs operating system function  "cmd"  passing
                    that  function  "args" as arguments.  This command
                    always returns a value as follows:

                     -1    Function "cmd" successfully performed.
                      0    Function "cmd" is unsupported.
                    Other  Function "cmd" attempted, but failed.   The
                           returned value is the failure status.

                    There  are  four  functions  that   are   commonly
                    defined:

                    INI    Locates the user's  private  initialization
                           TECO macro.
                    LIB    Defines the user's private library of  TECO
                           macros.
                    MEM    Read/write TECO's last edited file memory.
                    VTE    Locates the user's  private  scope  editing
                           TECO macro.

                    These four functions work as follows:

                    :EGcmd`       Loads   Q-register   *   with    the

     Standard TECO                                             PAGE 53
     File Close and Exit Commands


                                  requested  information.  If there is
                                  no  information   (e.g.,   no   user
                                  private  scope  editing  TECO macro)
                                  then Q-register * is set to the null
                                  string.

                    :EGcmd `      Clears   the   information   holder.
                                  Subsequent :EGcmd` commands will set
                                  Q-register * to the null string.

                    :EGcmd text`  Sets  the  information   holder   to
                                  "text".  Subsequent :EGcmd` commands
                                  will set Q-register * to "text".

                    Consult the appendices for details.

     EK             Kill the current  output  file  on  the  currently
                    selected   output  stream.   This  command,  which
                    purges the output  file  without  closing  it,  is
                    useful  to abort an undesired edit.  Executing the
                    EK command after an EW  which  is  superseding  an
                    existing  file leaves the old file intact.  The EK
                    command  also  "undoes"  an  EB   command.    (See
                    appendices for details.)

     ELfilespec`    Open the specified file for output as a log  file.
                    Any  currently  open  log file will be closed.  If
                    the /APPEND switch  is  given,  future  logs  will
                    append  to  the  file (if it already exists).  The
                    default is to supersede.  All type-in to TECO  and
                    all  type  out  from  TECO goes into the log file.
                    The log file is automatically closed by the EX and
                    <CTRL/C><CTRL/C> TECO commands.
                    [TECO-10 only]

     EX             Performs the same function as the EC command,  but
                    then  exits  from  TECO.  For safety reasons, this
                    command is aborted if there is text  in  the  text
                    buffer  but  no output file is open.  To exit TECO
                    after just looking at  a  file,  use  the  command
                    string HKEX.

     EZfilespec`    This command is useful for outputting to  magtapes
                    and  DECtapes, on which it initializes (zeros) the
                    specified output device before switching the ouput
                    to  the  primary  output stream.  In the case of a
                    magtape, this command rewinds the magtape to  load
                    point.   If  the  output  device  is  a disk, this
                    command works exactly like the EW command.
                    [TECO-10 only]

     <CTRL/C>       The   <CTRL/C>   (caret/C)   command    terminates
                    execution   of  the  current  command  string  and

     Standard TECO                                             PAGE 54
     File Close and Exit Commands


                    returns control to TECO's prompt.  (Under  TECO-8,
                    the    <CTRL/C>    command   currently   acts   as
                    <CTRL/C><CTRL/C>.)

     <CTRL/C><CTRL/C>
                    The ^C<CTRL/C> command causes an  immediate  abort
                    and  exit from TECO.  Currently open files are not
                    necessarily closed.  See the appendices  for  more
                    details.  Note that the second <CTRL/C> may not be
                    entered in up-arrow mode.


     5.1.4 Secondary Stream Commands

     TECO-11 provides  secondary  input  and  output  streams.   These
     permit  the  user  to have two input and two output files open at
     the same time, and to switch processing back  and  forth  between
     them.   Each stream maintains its file position independently, so
     that one can read from one stream (for example),  switch  to  the
     other,  and  then  switch back to the first and resume from where
     one left off.  In addition, a separate command stream allows  one
     to  execute  TECO  commands from a file without disturbing either
     input stream.

     The following commands manipulate the secondary input and  output
     streams:


                   TABLE 5-1D: SECONDARY STREAM COMMANDS
                        [Not in TECO-8 or TECO-10]

     Input commands (do not open or close any file;  do not change the
     text buffer):

     EP             Switches the input to the secondary input stream.

     ER`            Switches the input to the primary input stream.

     Output commands (do not open or close any file;   do  not  change
     the text buffer):

     EA             Switches  the  output  to  the  secondary   output
                    stream.

     EW`            Switches the output to the primary output stream.

     Indirect file commands:

     EIfilespec`    Opens a file as an indirect command file, so  that
                    any  further TECO requests for terminal input will
                    come from this  file.   At  end-of-file,  or  upon
                    TECO's  receipt of any error message, the indirect
                    command file will be  closed  and  terminal  input

     Standard TECO                                             PAGE 55
     Secondary Stream Commands


                    will  be switched back to the terminal.  Note that
                    this command only presets where  input  will  come
                    from;   it  does not "splice" the file's data into
                    the current command string.

                    While  end-of-file  closes  the  indirect  command
                    file, it does not automatically start execution of
                    commands.  Execution will begin only  upon  TECO's
                    receipt  of  two  adjacent  <ESC>s.  For instance,
                    assume that FOO.TEC contains valid TECO  commands,
                    that it presets a return to your terminal with the
                    customary EI`, but that it  does  not  contain  an
                    <ESC><ESC>  pair.   If you type EIFOO``, TECO will
                    read  in  the  contents  of  FOO.TEC  (building  a
                    command  string)  and attempt to continue building
                    the command string by reading from  your  terminal
                    when  end  of  file  on  FOO.TEC  is  encountered.
                    Things will appear "very quiet" until it occurs to
                    you  to type <DELIM><DELIM> and so begin execution
                    of the (composite) command string.

                    All commands encountered in the indirect file will
                    have  their normal TECO meaning (as opposed to any
                    immediate  action  meaning).    For   example,   a
                    <CTRL/U>  encountered in an indirect file will not
                    erase  the  command  line  in  which  it   occurs.
                    Instead,  it  will be treated as the TECO ^Uqtext`
                    command.  The only exception to this rule  is  the
                    <ESC><ESC>  command, which directs TECO to execute
                    the preceding command string and  then  return  to
                    the  indirect  file  at  the  point  following the
                    <ESC><ESC>.  (We can say  <ESC>  explicitly  here,
                    because  <DELIM>  can be other than ESCape only in
                    commands typed at the console.)

     EI`            If  an  indirect  command  file  is  active,  this
                    command  will  close  it and resume terminal input
                    from the terminal.  Any portion of the file  after
                    a  double  <DELIM>  which has not yet been read is
                    discarded.  This  command  has  no  effect  if  no
                    indirect file is already open.

     Standard TECO                                             PAGE 56
     Wildcard Commands


     5.1.5 Wildcard Commands

     TECO-11 supports wild card file processing with a set of  special
     commands, to allow TECO programs to operate on a set of files.


                       TABLE 5-1E: WILDCARD COMMANDS
                        [Not in TECO-8 or TECO-10]

     ENfilespec`    This  command  presets  the  "wild  card"   lookup
                    filespec.  It is only a preset;  it does not open,
                    close, or try to find any file.  The  "wild  card"
                    lookup  is  the only filespec that can contain any
                    wild card notations.  See the appendices  for  the
                    allowed wild fields in each operating system.

     EN`            Once  the  wild  card  lookup  filespec  has  been
                    preset,  executing this command will find the next
                    file that matches  the  preset  wild  card  lookup
                    filespec  and  will  load the filespec buffer with
                    that file's name.  The G* command (see Appendix C,
                    section  C.1.1)  can be used to retrieve the fully
                    expanded filespec.  When no more occurences of the
                    wild  card  filespec  exist,  the  ?FNF  error  is
                    returned.

     :EN`           Executes the EN` command, and  returns  a  numeric
                    value.   A  -1 indicates that another match of the
                    wild card filespec exists and has been loaded into
                    the  filespec  buffer.   A  0  indicates  no  more
                    occurences exist.  No error message is generated.

     The filespec argument to the file selection commands  in  TECO-11
     can  use  the  string building characters described in Table 5-8A
     (see  section  5.8).   The  <CTRL/E>Q*  construct,  described  in
     Appendix C, is especially useful in TECO-11.


     5.1.6 Direct I/O to Q-Registers

     TECO-10 provides commands to do I/O  directly  to  and  from  the
     Q-registers, allowing I/O to bypass the text buffer.


                   TABLE 5-1F: DIRECT I/O TO Q-REGISTERS
                        [Not in TECO-8 or TECO-11]

     EQqfilespec`   Read specified file into Q-register q.  No <NULL>s
                    or  <FF>s  are  removed from the file, except that
                    trailing <NULL>s are discarded.  The  only  switch
                    permitted  on  the filespec in this command is the
                    /DELETE switch, which causes TECO  to  delete  the
                    file  after reading it, providing that the file is

     Standard TECO                                             PAGE 57
     Direct I/O to Q-Registers


                    less  than  500  characters  long.   This  command
                    supports   the  pseudo-device  TMP:,  for  TMPCOR.
                    Consult the appropriate appendix for details.
                    [TECO-10 only]

     E%qfilespec`   Create the specified file.  The  contents  of  the
                    file  will be the contents of Q-register q with no
                    <NULL>s deleted.  No switches are permitted on the
                    filespec  of  this command.  This command supports
                    the pseudo-device TMP:, for TMPCOR.   Consult  the
                    appropriate appendix for details.
                    [TECO-10 only]

     Standard TECO                                             PAGE 58
     Page Manipulation Commands


     5.2 PAGE MANIPULATION COMMANDS

     The following commands permit text  to  be  read  into  the  text
     buffer  from  an  input  file  or written from the buffer onto an
     output file.

     All of the input commands listed in this table  assume  that  the
     input  file  is  organized  into  pages  small enough to fit into
     available memory.  If any page of the input  file  contains  more
     characters than will fit into available memory, the input command
     will continue reading characters into the  buffer  until  a  line
     feed  is  encountered when the buffer is about 3/4 full.  See the
     appendices for more details.   Special  techniques  for  handling
     pages  larger than the buffer capacity will be presented later in
     this chapter.


                  TABLE 5-2:  PAGE MANIPULATION COMMANDS

     COMMAND        FUNCTION

     APPEND commands:

     A         Appends the next page of the input file to the contents
               of  the  text  buffer,  thus combining the two pages of
               text on a single page with  no  intervening  form  feed
               character.  This command takes no argument.  To perform
               n Appends, use the n<A> construct.  Note that nA  is  a
               completely different command.

     :A        Equivalent to the A command  except  that  a  value  is
               returned.   -1 is returned if the append succeeded, and
               0  is  returned  if  the  append  failed  because   the
               end-of-the-input-file  had  previously been reached (^N
               flag is -1 at start of this command).
               [Not in TECO-8]

     n:A       Appends n lines of text from  the  input  file  to  the
               contents  of  the text buffer.  The value of n must not
               be negative.  A value is returned indicating whether or
               not  there  were in fact n lines remaining in the input
               file.  -1 is returned if the command succeeded.   0  is
               returned   if   end-of-file   on  the  input  file  was
               encountered before all n lines were read in.  Note that
               the  command  can  succeed and yet read in fewer than n
               lines in the case that the text buffer fills up.
               [Not in TECO-8]

     PAGE Commands:

     P         Writes the contents of the buffer onto the output file,
               then  clears  the buffer and reads the next page of the
               input file into the buffer.  A form feed is appended to

     Standard TECO                                             PAGE 59
     Page Manipulation Commands


               the  output file if the last page read in (with a P, Y,
               or A command) was terminated with a form feed.

     :P        Same as the P command except that a value is  returned.
               -1 is returned if the command succeeded.  0 is returned
               if the command failed because the  end-of-file  on  the
               input  file had been reached prior to the initiation of
               this command.  The command string <:P;>  takes  you  to
               end of file.
               [Not in TECO-8]

     nP        Executes the P command n  times,  where  n  must  be  a
               non-zero positive integer.

               In TECO-11 on VAX/VMS, n can be a negative integer (and
               -P means -1P).  A -nP command will back up n pages.

     n:P       Executes the :P command n times,  where  n  must  be  a
               non-zero  positive  integer.   In TECO-11 on VAX/VMS, n
               can be a negative integer (and -:P means  -1:P).   This
               command returns 0 when another page could not be backed
               up because beginning of file had been reached.
               [Not in TECO-8]

     PW        Write the contents of the buffer onto the  output  file
               and  append  a  form feed character.  The buffer is not
               cleared and the pointer position remains unchanged.

     nPW       Executes the PW command n times,  where  n  must  be  a
               non-zero positive integer.

     m,nPW     Writes the  contents  of  the  buffer  between  pointer
               positions  m  and n onto the output file.  m and n must
               be positive integers.  A form feed is not  appended  to
               this  output,  nor  is the buffer cleared.  The pointer
               position remains unchanged.

     m,nP      Equivalent to m,nPW.

     HPW       Equivalent to the PW command except that  a  form  feed
               character is not appended to the output.

     HP        Equivalent to HPW.

     YANK commands:

     Y         Clears the text buffer and then reads the next page  of
               the  input file into the buffer.  Because the Y command
               DESTROYS the current text buffer, its use can result in
               the  loss  of data, and is subject to "Yank protection"
               (see ED flag in section 5.14).

     -Y        Clears the text buffer and then reads the previous page

     Standard TECO                                             PAGE 60
     Page Manipulation Commands


               of the file being edited back into the buffer.  Because
               the Y command DESTROYS the current text buffer, its use
               can result in the loss of data, and is subject to "Yank
               protection" (see ED flag in section 5.14).
               [TECO-11 on VAX/VMS only]

     :Y        Same as the Y command but a value is returned.   -1  is
               returned  if  the Yank succeeded.  0 is returned if the
               Yank failed because the end-of-file had been reached on
               the input file prior to the initiation of this command.
               [Not in TECO-8]

     -:Y       Same as the -Y command but a value is returned.  -1  is
               returned  if  the Yank succeeded.  0 is returned if the
               Yank failed because the  beginning  of  file  had  been
               reached   on   the  file  being  edited  prior  to  the
               initiation of this command.
               [TECO-11 on VAX/VMS only]

     EY        Same as  the  Y  command,  but  its  action  is  always
               permitted   regardless   of   the  value  of  the  Yank
               Protection bit in the  ED  flag.   Remember  that  Yank
               DESTROYS  the current buffer;  there's no way to get it
               back!

     :EY       Same as the  :Y  command,  but  its  action  is  always
               permitted   regardless   of   the  value  of  the  Yank
               protection bit in the  ED  flag.   Remember  that  Yank
               DESTROYS  the current buffer;  there's no way to get it
               back!
               [Not in TECO-8]

     Standard TECO                                             PAGE 61
     Buffer Pointer Manipulation Commands


     5.3 BUFFER POINTER MANIPULATION COMMANDS

     Table 5-3  describes  all  of  the  buffer  pointer  manipulation
     commands  These  commands  may  be  used to move the pointer to a
     position between any two characters in the buffer, but they  will
     not  move  the  pointer  across a buffer boundary.  If any R or C
     command  attempts  to  move  the  pointer  backward  beyond   the
     beginning  of  the  buffer or forward past the end of the buffer,
     the command is ignored and an error message is printed.  If any L
     command  attempts to exceed the buffer boundaries, the pointer is
     positioned at the boundary which would have been exceeded and  no
     error message is printed.


             TABLE 5-3:  BUFFER POINTER MANIPULATION COMMANDS

     COMMAND        FUNCTION

     CHARACTER commands:

     C         Advances the pointer forward across one character.

     nC        Executes the C command n times.  If n is positive,  the
               pointer  is moved forward across n characters.  If n is
               negative,  the  pointer  is  moved  backward  across  n
               characters.   If n is zero, the pointer position is not
               changed.

     n:C       Same as nC except that a value  is  returned.   If  the
               command  succeeded,  -1  is  returned.   If the command
               failed, the pointer does not move and a value of  0  is
               returned.
               [TECO-10 only]

     :C        Equivalent to 1:C.

     -C        Equivalent to -1C.

     JUMP commands:

     J         Moves the pointer to a position  immediately  preceding
               the first character in the buffer.  Equivalent to 0J.

     nJ        Moves the pointer to a position  immediately  following
               the nth character in the buffer.

     ZJ        Moves the pointer to a position  immediately  following
               the last character in the buffer.

     n:J       Same as the nJ command except that if pointer  position
               n  is  outside of the buffer, the pointer does not move
               and  a  value  of  0  is  returned.   If  the   command
               succeeded, a value of -1 is returned.

     Standard TECO                                             PAGE 62
     Buffer Pointer Manipulation Commands


               [TECO-10 only]

     LINE commands:

     L         Advances the  pointer  forward  across  the  next  line
               terminator  (line feed, vertical tab, or form feed) and
               positions it at the beginning of the next line.

     nL        Executes the L command n times.  A positive value of  n
               advances  the  pointer to the beginning of the nth line
               following its current position.  A negative value of  n
               moves the pointer backwards to the beginning of the nth
               complete line preceding its current position.  If n  is
               zero, the pointer is moved to the beginning of the line
               on which it is currently positioned.

     -L        Equivalent to -1L.

     REVERSE commands:

     R         Moves the pointer backward across one character.

     nR        Executes the R command n times.  If n is positive,  the
               pointer is moved backward across n characters.  If n is
               negative,  the  pointer  is  moved  forward  across   n
               characters.   If n is zero, the position of the pointer
               is not changed.

     -R        Equivalent to -1R.

     n:R       Same as the nR command except that a value is returned.
               If  the  command  succeeded,  then  a  value  of  -1 is
               returned.  If  the  command  failed,  then  the  buffer
               pointer is not moved and a value of 0 is returned.
               [TECO-10 only]

     :R        Equivalent to 1:R.

     Standard TECO                                             PAGE 63
     Text Type Out Commands


     5.4 TEXT TYPE OUT COMMANDS

     Table 5-4 describes the commands used to type out part or all  of
     the  contents  of  the buffer for examination.  These commands do
     not move the buffer pointer.


                    TABLE 5-4:  TEXT TYPE OUT COMMANDS

     COMMAND        FUNCTION

     T         Types out the contents of the buffer from  the  current
               position  of  the  buffer pointer through and including
               the next line terminator character.

     nT        Types n lines.  If n is positive,  types  the  n  lines
               following the current position of the pointer.  If n is
               negative, types the n lines preceding the pointer.   If
               n  is  zero,  types the contents of the buffer from the
               beginning of the line on which the pointer  is  located
               up to the pointer.

     -T        Equivalent to -1T.

     m,nT      Types out the contents of the  buffer  between  pointer
               positions m and n.

     .,.+nT    Types out the n characters  immediately  following  the
               buffer pointer.  n should be greater than zero.

     .-n,.T    Types the n characters immediately preceding the buffer
               pointer.  n should be greater than zero.

     n^T       Types out to the  console  the  character  whose  ASCII
               value  is  n.  Whatever normal type-out conversions may
               currently  be  in  effect  and  applicable   (such   as
               translation  of  control characters to up-arrow format)
               are done.  The value of n is used modulo 256.

     n:^T      Outputs to the console the character whose ASCII  value
               is  n.   Output  is done in "one-shot" binary mode;  no
               type-out translations are done.  The value of n is used
               modulo 256.
               [TECO-11 only]

     HT        Types out the entire contents of the buffer.

     V         Types out the current line.  Equivalent to 0TT.

     nV        Types out n-1 lines on each side of the  current  line.
               Equivalent to 1-nTnT.
               [Not in TECO-8]

     Standard TECO                                             PAGE 64
     Text Type Out Commands


     m,nV      Types out m-1 lines before  and  n-1  lines  after  the
               current line.
               [Not in TECO-8]

     ^Atext<CTRL/A>
               Types "text" on the terminal.  While  the  command  may
               begin  with  <CTRL/A> or Caret/A, the closing character
               must be a <CTRL/A>.  A numeric  argument  must  not  be
               specified with this command.

     @^A/text/ Equivalent to the ^A command except that the text to be
               printed  may  be  bracketed  with  any character.  This
               avoids the need for the closing <CTRL/A>.

     Standard TECO                                             PAGE 65
     Text Type Out Commands


     You may stop or delay the output  of  any  type  out  command  by
     typing  certain  special characters at the keyboard while TECO is
     typing out at the terminal (via a  T,  V,  ^A,  or  :G  command).
     These characters are described in the table below:


                    TABLE 5-4B: TYPE OUT TIME COMMANDS

     CHARACTER      FUNCTION

     <CTRL/O>     Stops the terminal output  of  the  current  command
                  string.    TECO   continues   to  run  and  to  send
                  characters   to   the   terminal,   however,   these
                  characters  are suppressed from actually printing on
                  the terminal.  You can resume printing characters by
                  typing  another  <CTRL/O>  while  type  out is being
                  suppressed.  TECO cancels this suppression the  next
                  time  that  it  prompts for command string input.  A
                  TECO macro can cancel the effect of any <CTRL/O>  by
                  setting  the  16's  bit  in the ET flag (see section
                  5.16).

     <CTRL/S>     Freezes the terminal output of the  current  command
                  string.   TECO  stops running the next time it tries
                  to output a character to your  terminal,  and  waits
                  for  you  to type a <CTRL/Q> to indicate that output
                  should resume.

     <CTRL/Q>     Causes TECO to resume any type out that  was  frozen
                  via  use  of  the  <CTRL/S> command described above.
                  This character has this effect only while typout  is
                  frozen.   Striking  any  key  other than <CTRL/Q> or
                  <CTRL/C>  while  type  out  is  frozen   will   have
                  unpredictable   results;   consult  the  appropriate
                  operating system manual.


     Note  that  <CTRL/O>,  <CTRL/Q>,  and  <CTRL/S>  are  legal  TECO
     commands  as well.  When TECO is not typing on the terminal (when
     you are entering a command string, for example), these characters
     do not have the effect described above.  They may be entered into
     your command string just like any other control character (except
     under operating systems that filter out these characters).

     Standard TECO                                             PAGE 66
     Deletion Commands


     5.5 DELETION COMMANDS

     Table 5-5 summarizes the text  deletion  commands,  which  permit
     deletion  of  single  characters,  groups of adjacent characters,
     single lines, or groups of adjacent lines.


                    TABLE 5-5:  TEXT DELETION COMMANDS

     COMMAND        FUNCTION

     DELETE commands:

     D         Delete  the  first  character  following  the   current
               position of the buffer pointer.

     nD        Execute the D command n times.  If n is positive, the n
               characters  following  the current pointer position are
               deleted.  If n is negative, the n characters  preceding
               the  current  pointer  position  are  deleted.  If n is
               zero, the command is ignored.

     -D        Equivalent to -1D.

     m,nD      Equivalent to m,nK.
               [TECO-11 only]

     n:D       Same as nD but returns a value (-1 if command succeeds,
               0  if command failed because the range of characters to
               be deleted fell outside the text buffer).
               [TECO-10 only]

     FDtext`   Search for the specified text  string  and  delete  it.
               (See search commands in section 5.7.)
               [TECO-10 only]

     @FD/text/ Equivalent to FDtext` except that the <DELIM> character
               is not necessary.

     FR`       Equivalent to -nD where n is the  length  of  the  last
               insert,  get or search command.  See the description of
               the FRtext` command in section 5.6 for more details.

     @FR//     Form of the FR` command that does not  require  use  of
               the <DELIM> character.

     KILL commands:

     K         Deletes the contents of the  buffer  from  the  current
               position  of  the  buffer pointer through and including
               the next line terminator character.

     nK        Executes the K command n times.  If n is positive,  the

     Standard TECO                                             PAGE 67
     Deletion Commands


               n  lines  following  the  current  pointer position are
               deleted.  If n is negative, the n lines  preceding  the
               current  pointer  position  are deleted.  If n is zero,
               the contents of the buffer from the  beginning  of  the
               line  on which the pointer is located up to the pointer
               is deleted.  It is not  an  error  if  more  lines  are
               specified than occur when a boundary of the text buffer
               is encountered.

     -K        Equivalent to -1K.

     m,nK      Deletes the contents  of  the  buffer  between  pointer
               positions  m  and n.  The pointer moves to the point of
               the  deletion.   The  ?POP  error   message   (or   its
               equivalent) is issued if either m or n is out of range.

     FKtext`   Executes a Stext` command then  deletes  all  the  text
               from  the  initial  pointer position to the new pointer
               position.
               [TECO-10 only]

     @FK/text/ Equivalent to FKtext` except that  "text"  may  contain
               any  character,  including  <ESCAPE>,  other  than  the
               delimiter (shown here as /).
               [TECO-10 only]

     HK        Deletes the entire contents of the buffer.

     Standard TECO                                             PAGE 68
     Insertion Commands


     5.6 INSERTION COMMANDS

     Table 5-6 lists  all  of  the  text  insertion  commands.   These
     commands  cause the string of characters specified in the command
     to be inserted into the text buffer at the  current  position  of
     the buffer pointer.  Following execution of an insertion command,
     the  pointer  will  be  positioned  immediately  after  the  last
     character of the insertion.

     The length of an insertion command is limited  primarily  by  the
     amount  of  memory  available for command string storage.  During
     normal editing jobs, it is most convenient to limit insertions to
     about 10 or 15 lines each.  When command string space is about to
     run out, TECO will ring the terminal's bell after each  character
     that  is  typed.   From the time you hear the first warning bell,
     you have 10 characters to type in order to clean up your  command
     line.   Attempting  to enter too many characters into the current
     command string causes unpredictible results to occur  and  should
     be  avoided.  Use the DELETE key to shorten the command to permit
     its termination.

     As explained above in Chapter 4, certain characters are  filtered
     out by the operating system and/or may perform special functions,
     and some  characters  are  immediate  action  commands  and  have
     special  effect.   If you want to insert such characters into the
     text buffer, use the  nI`  command  described  in  the  following
     table.   It  will  insert  any  ASCII  character into the buffer,
     including the special characters that  could  not  ordinarily  be
     typed at a terminal.


                    TABLE 5-6:  TEXT INSERTION COMMANDS

     COMMAND        FUNCTION

     INSERT commands:

     Itext`    Where "text" is a string of ASCII characters terminated
               by  a  <DELIM>.   The  specified text string is entered
               into the buffer at the current position of the pointer,
               with  the pointer positioned immediately after the last
               character of the insertion.

     nI`       This form of the I command inserts the single character
               whose  ASCII  code  is n into the buffer at the current
               position of the buffer pointer.  (n is taken modulo 256
               in  TECO-11, modulo 128 in other TECOs.) nI` is used to
               insert characters that are not available on the  user's
               terminal or special characters such as DELETE which may
               not be inserted from a terminal  with  the  standard  I
               command.

     @I/text/  Equivalent to the I command except that the text to  be

     Standard TECO                                             PAGE 69
     Insertion Commands


               inserted  may  contain ESCAPE characters.  A delimiting
               character (shown as a  slash  here)  must  precede  and
               follow the text to be inserted, as described in Section
               3.1.2 above.

     n@I//     Equivalent to the nI` command, but does not require the
               <DELIM> character.

     <TAB>text` This command is equivalent to  the  I  command  except
               that  the  <TAB>  is part of the text which is inserted
               into the buffer.

     FRtext`   Equivalent to "-nDItext`", where "n" is  obtained  from
               the  most  recent occurrence of the following:  (a) the
               length of the most recent string found by a  successful
               search  command, (b) the length of the most recent text
               string inserted (including insertions from the FS,  FN,
               or  FR  commands),  or  (c)  the  length  of the string
               retrieved by the most recent "G" command.   In  effect,
               the  last  string  inserted  or  found is replaced with
               "text", provided that the pointer has not  been  moved.
               After  execution of this command, the buffer pointer is
               positioned immediately after "text".
               [Not in TECO-8]

     @FR/text/ Equivalent to "FRtext`", except that "text" may contain
               ESCAPE characters.
               [Not in TECO-8]

     nFRtext`  Equivalent  to  "nDItext`".   If  n  is  less  than  0,
               characters preceding the buffer pointer are deleted and
               replaced  with  "text".   If  n  is  greater  than   0,
               characters following the buffer pointer are deleted and
               replaced with  "text".   In  either  case,  the  buffer
               pointer  is  left  positioned  immediately after "text"
               upon completion of this command.
               [TECO-11 only]

     n@FR/text/ Equivalent  to  "nFRtext`",  except  that  "text"  may
               contain ESCAPE characters.
               [TECO-11 only]

     m,nFRtext` Equivalent to "m,nDItext`".   The  characters  between
               buffer  positions m and n are deleted and replaced with
               "text".   The  buffer  pointer   is   left   positioned
               immediately   after  "text"  upon  completion  of  this
               command.
               [TECO-11 only]

     m,n@FR/text/ Equivalent to "m,nFRtext`", except that  "text"  may
               contain ESCAPE characters.
               [TECO-11 only]

     Standard TECO                                             PAGE 70
     Search Commands


     5.7 SEARCH COMMANDS

     In many cases, the easiest way to position the buffer pointer  is
     by  means  of  a  character string search.  Search commands cause
     TECO to scan through text until a specified string of  characters
     is  found, and then position the buffer pointer at the end of the
     string.  A character string search begins at the current position
     of  the  pointer.   It  proceeds  within  the current buffer in a
     forward or a reverse direction or through the file in  a  forward
     direction.   Specifying a negative numeric argument to the search
     command causes the search to proceed backwards from the pointer.

     Your last explicitly specified search string is always remembered
     by  TECO.   If  a  search command is specified with a null search
     string argument, the last explicitly defined search  string  will
     be used.  This saves having to retype a complex or lengthy search
     string on successive search commands.

     Normally searches are "unbounded" - they search from the  current
     position  to  the  end  of  the  text  buffer  (or in the case of
     backwards searches,  until  the  beginning  of  the  buffer).   A
     bounded  search,  however,  will  only  search  from  the current
     position to the specified bound limit.  If the search  string  is
     found   within  the  bound  limits,  the  pointer  is  positioned
     immediately after the last  character  in  the  string.   If  the
     string cannot be found, the pointer is left unchanged.

     A special case of the bounded search occurs when  the  upper  and
     lower  bound  limits  are  the  same.  In such a case, the search
     command is called an anchored search, and is used to compare  the
     search   argument   against   the  character  string  immediately
     following the text buffer pointer.

     TECO-8 does not permit backward, bounded, or  anchored  searches.
     This is a general property and will not be specifically mentioned
     again in the following tables.

     Standard TECO                                             PAGE 71
     Search Commands


                       TABLE 5-7A:  SEARCH COMMANDS

     Stext`    Where "text" is a string of characters terminated by  a
               <DELIM>.  This command searches the text buffer for the
               next  occurrence  of  the  specified  character  string
               following  the  current position of the buffer pointer.
               If the string is found, the pointer is positioned after
               the  last character in the string.  If it is not found,
               the pointer is positioned immediately before the  first
               character in the buffer (i.e., a 0J is executed) and an
               error message is printed.

     nStext`   This command searches for the  nth  occurrence  of  the
               specified  character  string,  where  n is greater than
               zero.  It is  identical  to  the  S  command  in  other
               respects.

     -nStext`  Identical to "nStext`" except that the search  proceeds
               in  the reverse direction.  If the string is not found,
               the pointer is positioned immediately before the  first
               character  in  the  buffer  and  an  error  message  is
               printed.  If the pointer is positioned at the beginning
               of  or within an occurrence of the desired string, that
               occurrence is considered to be  the  first  one  found.
               Upon  successful  completion, the pointer is positioned
               after the last character in the string found.

     -Stext`   Equivalent to -1Stext`.

     Ntext`    Performs the same function as the S command except that
               the  search  is  continued  across  page boundaries, if
               necessary, until the character string is found  or  the
               end of the input file is reached.  This is accomplished
               by executing an effective P command after each page  is
               searched.   If the end of the input file is reached, an
               error message is printed and it is necessary  to  close
               the  output file and re-open it as an input file before
               any further editing may be done on that  file.   The  N
               command  will not locate a character string which spans
               a page boundary.

     -Ntext`   Performs the same function as  the  -S  command  except
               that  the  search  is continued (backwards) across page
               boundaries, if necessary, until the character string is
               found  or  the  beginning  of  the file being edited is
               reached.
               [TECO-11 on VAX/VMS only]

     -nNtext`  This  command  searches   (backwards)   for   the   nth
               occurrence  of  the  specified character string.  It is
               identical to the -N command in other respects.
               [TECO-11 on VAX/VMS only]

     Standard TECO                                             PAGE 72
     Search Commands


     nNtext`   This command searches for the  nth  occurrance  of  the
               specified  character  string,  where  n must be greater
               than zero.  It is identical to the N command  in  other
               respects.

     _text`    The underscore command is identical to  the  N  command
               except   that  the  search  is  continued  across  page
               boundaries by executing effective Y commands instead of
               P  commands,  so that no output is generated.  Since an
               underscore search can result in the loss of data, it is
               aborted  under  the same circumstances as the Y command
               (see  the  ED  flag  in  section  5.16).    Note   that
               underscore is backarrow on some terminals.

     n_text`   This command searches for the  nth  occurrence  of  the
               specified  character  string,  where  n must be greater
               than zero.  It is identical to the _ command  in  other
               respects.

               In TECO-11 on VAX/VMS, n can be negative, in which case
               the  search proceeds backwards through each text buffer
               and through the file being edited.  It terminates  upon
               the  correct  search  string  match and/or beginning of
               file.  A -n:_ command returns 0 at beginning of file.

     E_text`   Same as _text` command except that effective EY (rather
               than Y) commands are used.  Thus, this command is never
               aborted and is not controlled by  the  Yank  protection
               bit  in  the  ED flag.  Remember that Yank DESTROYS the
               current buffer;  there's no way to get it back!

     nE_text`  Same  as  n_text`  command  except  that  effective  EY
               (rather than Y) commands are used.

     Standard TECO                                             PAGE 73
     Search Commands


                    TABLE 5-7B: BOUNDED SEARCH COMMANDS

     m,nStext` System specific command.  Consult Appendix C.

     m,nFBtext` Performs the same function as the nStext` command, but
               m and n (inclusive) serve as bounds for the search.  In
               order  for  a  search  to  be  successful,  the   first
               character  to  match  must occur between buffer pointer
               positions m and n.   The  string  that  is  matched  is
               permitted to extend beyond the search limits specified,
               provided that it begins within bounds.   If  m<n,  then
               the  search  proceeds in a forwards direction.  If m>n,
               then the search proceeds in the reverse direction.

     nFBtext`  Performs a bounded search over the next n lines.  If  n
               is  positive, the search proceeds forward over the next
               n  lines;   if  n  is  negative  the  search   proceeds
               backwards  over  the  n preceding lines;  if n is zero,
               the search proceeds backwards over the portion  of  the
               line preceding the pointer.

     FBtext`   Equivalent to 1FBtext`.

     -FBtext`  Equivalent to -1FBtext`.

     ::Stext`  Compare command.  The ::S command is not a true search.
               If  the  characters in the buffer immediately following
               the current pointer position match the  search  string,
               the  pointer  is moved to the end of the string and the
               command returns a value of -1;  i.e., the next  command
               is  executed with an argument of -1.  If the characters
               in the buffer do not match the string, the  pointer  is
               not  moved  and  the  command  returns  a  value  of 0.
               Identical to ".,.:FBtext`".



     The search and replace commands listed below  perform  equivalent
     functions  to  the  search commands listed next to them, but then
     delete "text1" and replace it with "text2".


                  TABLE 5-7C: SEARCH AND REPLACE COMMANDS

               Search & Replace              Search Command

               FStext1`text2`                Stext1`

               nFStext1`text2`               nStext1`

               FNtext1`text2`                Ntext1`

               nFNtext1`text2`               nNtext1`

     Standard TECO                                             PAGE 74
     Search Commands


               F_text1`text2`                _text1`
               [not in TECO-10]

               nF_text1`text2`               n_text1`
               [Not in TECO-10]

               FCtext1`text2`                FBtext1`

               nFCtext1`text2`               nFBtext1`

               m,nFCtext1`text2`             m,nFBtext1`


     In addition, the four following commands can be used on TECO-10:

     FDtext`   Identical to the "FStext``" command.
               [TECO-10 only]

     nFDtext`  Identical to the "nFStext``" command.
               [TECO-10 only]

     nFKtext`  Searches for the nth following occurrence of "text" and
               then  deletes all characters in the text buffer between
               the pointer positions before and after the search.
               [TECO-10 only]

     FKtext`   Equivalent to 1FKtext`
               [TECO-10 only]

     The FS, F_, and FN commands above can also  be  reverse  searches
     (n<0)  or  bounded  searches  (m,n argument).  A reverse F_ or FN
     acts like a reverse S;  that is the search  terminates  when  the
     beginning of the text buffer is encountered.

     (In TECO-11 on VAX/VMS, -nFN searches backwards through each text
     buffer and through the file being edited.  It terminates upon the
     correct search string match and/or beginning of  file.   A  colon
     modified reverse search returns 0 at beginning of file.)

     If a search command is entered without a text argument, TECO will
     execute the search command as though it had been entered with the
     same  character  string  argument  as  the  last  search  command
     entered.  For example, suppose the command "STHE END`" results in
     an error message, indicating that character string "THE END"  was
     not  found on the current page.  Entering the command "N`" causes
     TECO to execute an  N  search  for  the  same  character  string.
     Although the text argument may be omitted, the command terminator
     <DELIM> must always be entered.

     Search commands can make use of the colon modifier  described  in
     Chapter  3.   The  following examples illustrate use of the colon
     modifier:

     Standard TECO                                             PAGE 75
     Search Commands


     COMMANDS:      n:Stext`
                    m,n:Stext`
                    n:Ntext`
                    n:_text`
                    n:FStext1`text2`
                    m,n:FStext1`text2`
                    n:FNtext1`text2`
                       etc.

     FUNCTION:      In each case, execute the search command.  If  the
                    search  is successful, execute the next sequential
                    command with an argument of  -1.   If  the  search
                    fails,  execute  the next command with an argument
                    of zero.  If the next command does not  require  a
                    numeric argument, execute it as it stands.



     All search commands may also use the @ modifier to use  alternate
     delimiters,  to allow <ESCAPE> characters in search strings or to
     avoid the use of <ESCAPE> characters in  command  strings.   Such
     search commands take the following forms:

     COMMANDS:      @S/text/
                    m,n@FB/text/
                    n@FS/text1/text2/
                    @:N/text/
                       etc.

     Standard TECO                                             PAGE 76
     Search Arguments


     5.8 SEARCH ARGUMENTS

     TECO builds the search string by loading its search string buffer
     from  the  supplied  search  command argument.  To help you enter
     special characters or frequently used  character  sequences,  the
     argument  may  contain special string building characters.  Table
     5-8A lists the string building characters and their functions.

     TECO-8 does not support the extended String  Build  functions  or
     Match  Control  Constructs  that  begin with <CTRL/E>.  This is a
     general property and  will  not  be  repeated  in  the  following
     tables.

     Note that, as explained in Chapter 3, a caret (up-arrow)  may  be
     used to indicate that the character following it is to be treated
     as a control character.  Any of the commands below may be entered
     using  the  caret.  This function of the caret can be disabled by
     using the ED flag (see 5.16 and appendices).


                  TABLE 5-8A:  STRING BUILDING CHARACTERS

     CHARACTER           FUNCTION

     <CTRL/Q>       A <CTRL/Q> character in a search command  argument
                    indicates   that   the   character  following  the
                    <CTRL/Q> is to be used literally rather than as  a
                    match control character.

     <CTRL/R>       Same as <CTRL/Q>.

     <CTRL/V>       A <CTRL/V> character in a search command  argument
                    indicates   that   the   character  following  the
                    <CTRL/V> is to be used as the equivalent character
                    in  the lower case ASCII range (i.e., octal 100 to
                    137 is treated as octal 140 to 177).

     <CTRL/V><CTRL/V>
                    Two successive <CTRL/V>  characters  in  a  string
                    argument  indicate  to  TECO  that  all  following
                    alphabetic characters in this  string  are  to  be
                    converted  to  lower case unless an explicit ^W is
                    given  to  override  this   state.    This   state
                    continues  until  the end of the string or until a
                    ^W^W construct is encountered.
                    [TECO-10 only]

     <CTRL/W>       A <CTRL/W> character in a search command  argument
                    indicates   that   the   character  following  the
                    <CTRL/W> is to be used as the equivalent character
                    in  the upper case ASCII range (i.e., octal 140 to
                    177 is treated as octal 100 to 137).

     Standard TECO                                             PAGE 77
     Search Arguments


     <CTRL/W><CTRL/W>
                    Two successive <CTRL/W>  characters  indicates  to
                    TECO  that  all following alphabetic characters in
                    this string are to  be  converted  to  upper  case
                    unless  an  explicit ^V is encountered to override
                    this state.  This state continues until the end of
                    the   string   or   until   a  ^V^V  construct  is
                    encountered.
                    [TECO-10 only]

     <CTRL/E>Qq     <CTRL/E>Qq indicates that  the  string  stored  in
                    Q-register  q  is  to  be  used  in  the  position
                    occupied by the ^EQq  in  the  search  string.   Q
                    registers are discussed in sections 3.3.2 and 5.9.
                    [Not in TECO-10]

     <CTRL/E>Uq     <CTRL/E>Uq  indicates  that  the  character  whose
                    ASCII  code  is  specified  by the numeric storage
                    area of Q-register q is to be used in the position
                    occupied by the ^EUq in the search string.
                    [TECO-11 only]


     String build characters are  also  permitted  inside  the  string
     arguments of the O, EB, ER, EW, and EG commands.

     TECO executes a search command by attempting to match the  search
     command  argument character-by-character with some portion of the
     input file.  There are several special  control  characters  that
     may  be  used  in  search  command  arguments  to alter the usual
     matching  process.   Table  5-8B  lists   these   match   control
     characters and their functions.


                   TABLE 5-8B:  MATCH CONTROL CHARACTERS

     CHARACTER           FUNCTION

     <CTRL/X>       A <CTRL/X> character indicates that this  position
                    in  the  character  string  may  be any character.
                    TECO  accepts  any  character  as  a   match   for
                    <CTRL/X>.

     <CTRL/S>       A <CTRL/S> character indicates that any  separator
                    character  is  acceptable  in this position.  TECO
                    accepts any character that is not a letter  (upper
                    or  lower  case  A  to Z) or a digit (0 to 9) as a
                    match for <CTRL/S>.

     <CTRL/N>x      TECO accepts any character  as  a  match  for  the
                    <CTRL/N>x  combination  EXCEPT the character which
                    follows the <CTRL/N>.  <CTRL/N>  can  be  combined
                    with  other  special characters.  For example, the

     Standard TECO                                             PAGE 78
     Search Arguments


                    combination <CTRL/N><CTRL/E>D means match anything
                    except a digit in this position.

     <CTRL/E>A      <CTRL/E>A indicates that any alphabetic  character
                    (upper or lower case A to Z) is acceptable in this
                    position.

     <CTRL/E>B      Same as <CTRL/S>.

     <CTRL/E>C      <CTRL/E>C indicates that  any  character  that  is
                    legal   as   part   of  a  symbol  constituent  is
                    acceptable in this  position.   TECO  accepts  any
                    letter  (upper or lower case A to Z), any digit (0
                    to 9), a dot (.), or a dollar sign ($) as a  match
                    for   <CTRL/E>C.   Additional  characters  may  be
                    matched  depending  upon  the  operating   system;
                    consult the appropriate appendix.

     <CTRL/E>D      <CTRL/E>D indicates that any digit  (0  to  9)  is
                    acceptable in this position.

     <CTRL/E>Gq     <CTRL/E>Gq indicates that any character  contained
                    in  Q-register  q  is acceptable in this position.
                    For example, if Q-register A contains  "A*:"  then
                    TECO  accepts  either  A,  *, or :  as a match for
                    <CTRL/E>GA.
                    [Not in TECO-10]

     <CTRL/E>L      <CTRL/E>L indicates that any line terminator (line
                    feed, vertical tab, or form feed) is acceptable in
                    the position occupied by <CTRL/E>L in  the  search
                    string.

     <CTRL/E>M      <CTRL/E>M indicates that any  non-zero  number  of
                    occurrences of the immediately following character
                    or match control construct is acceptable  at  this
                    position.
                    [TECO-10 only]

     <CTRL/E>R      <CTRL/E>R   indicates   that   any    alphanumeric
                    character  (letter  or  digit as defined above) is
                    acceptable in this position.

     <CTRL/E>S      <CTRL/E>S indicates that any  non-null  string  of
                    spaces  and/or  tabs is acceptable in the position
                    occupied by <CTRL/E>S.

     <CTRL/E>V      <CTRL/E>V indicates that any lower case alphabetic
                    character is acceptable in this position.

     <CTRL/E>W      <CTRL/E>W indicates that any upper case alphabetic
                    character is acceptable in this position.

     Standard TECO                                             PAGE 79
     Search Arguments


     <CTRL/E>X      Equivalent to <CTRL/X>.

     <CTRL/E><nnn>  <CTRL/E><nnn> indicates that the  character  whose
                    ASCII  octal  code  is  nnn  is acceptable in this
                    position.
                    [TECO-10 only]

     <CTRL/E>[a,b,c,...]
                    <CTRL/E>[a,b,c,...] indicates that any one of  the
                    specified   characters   is   acceptable  in  this
                    position.  One or more characters or  other  match
                    control constructs are permitted.
                    [TECO-10 only]

     TECO-8 uses special symbols to represent  certain  match  control
     characters  when  they  are displayed by an error message.  These
     display symbols are:

          Character      Display

          ^N             <NOT>
          ^S             <SEP>
          ^X             <ANY>

     Standard TECO                                             PAGE 80
     Q-registers


     5.9 Q-REGISTER MANIPULATION

     TECO provides data storage registers, called Q-registers, each of
     which  may  be  used  to  store  an  integral  numeric value and,
     simultaneously,  an  ASCII  character  string.   Q-registers  are
     described  in section 3.3.2;  this section describes the commands
     used to load values into and retrieve values from Q-registers.

     An important kind of character string which may be stored in  the
     text  portion  of  a Q-register is a TECO command string.  Such a
     command is known as a macro, and is available for  execution  via
     the Mq command, described in Table 5-9C below.  (See also section
     4.4, Immediate ESCape-sequence commands, for a keypad  method  of
     macro  invocation,  and  section  4.2,  for the *q command, which
     saves  the   last-typed   command   for   possible   editing   or
     re-execution.)

     TECO-10 allows additional Q-registers other than those  described
     in section 3.3.2.  Consult Appendix I for further details.

     Table 5-9A lists the  commands  which  permit  characters  to  be
     loaded into the Q-registers.


                 TABLE 5-9A:  Q-REGISTER LOADING COMMANDS

     COMMAND        FUNCTION

     nUq       Put n in the numeric storage area of Q-register q.

     m,nUq     Equivalent to the nUqm command.  That is, this  command
               puts  the  number  n  into  the numeric storage area of
               Q-register q and then returns the number m as a  value.
               The  command UAUB is useful at the beginning of a macro
               to save the two arguments specified on the macro  call.
               (See the m,nMq command below.)

     n%q       Add n to the contents of the  number  storage  area  of
               Q-register q.  The updated contents of Q-register q are
               also returned as a value  to  be  passed  to  the  next
               command.

               If your intent is only to update the  Q-register,  good
               programming practice suggests following the n%q command
               with a <DELIM> or ^[ to prevent the returned value from
               unintentionally affecting the following command.

     n%q`      Same as n%q but discards the value returned.

     %q        Equivalent to 1%q.

     ^Uqstring`
               This command inserts character string "string" into the

     Standard TECO                                             PAGE 81
     Q-registers


               text  storage  area  of  Q-register q.  When entering a
               command string from the terminal, you must  specify  ^U
               using  the caret/U format, since the <CTRL/U> character
               is the line erase immediate action command.

     :^Uqstring`
               This command appends character string "string"  to  the
               text storage area of Q-register "q".
               [not in TECO-8]

     n^Uq`     This form  of  the  ^Uq`  command  inserts  the  single
               character  whose  ASCII code is n into the text storage
               area of Q-register "q".  (n  is  taken  modulo  256  in
               TECO-11, modulo 128 in other TECOs.)
               [not in TECO-8]

     n:^Uq`    This form of  the  :^Uq`  command  appends  the  single
               character  whose  ASCII  code  is n to the text storage
               area of Q-register "q".  (n  is  taken  modulo  256  in
               TECO-11, modulo 128 in other TECOs.)
               [not in TECO-8]

     @^Uq/string/
     @:^Uq/string/
     n@^Uq//
     n@:^Uq//  Equivalent,   respectively,    to    the    ^Uqstring`,
               :^Uqstring`,  n^Uq`,  and  n:^Uq` commands, except that
               alternate delimiters are used and no <DELIM> characters
               are necessary.

     nXq       Clear Q-register q and move n lines into it, where n is
               a  signed  integer.   If  n  is  positive,  the n lines
               following the current pointer position are copied  into
               the  text  storage  area  of  Q-register  q.   If  n is
               negative, the n lines preceding the pointer are copied.
               If  n  is  zero,  the  contents  of the buffer from the
               beginning of the line on which the pointer  is  located
               up to the pointer is copied.  The pointer is not moved.
               The text is not deleted.

     Xq        Equivalent to 1Xq.

     -Xq       Equivalent to -1Xq.

     m,nXq     Copy  the  contents  of  the  buffer  from  the   m+1th
               character  through and including the nth character into
               the text storage area of Q-register q.  M and n must be
               positive, and m should be less than n.

     .,.+nXq   Copy the n characters immediately following the  buffer
               pointer  into the text storage area of Q-register q.  N
               should be greater than zero.

     Standard TECO                                             PAGE 82
     Q-registers


     .-n,.Xq   Copy the n characters immediately preceeding the buffer
               pointer  into the text storage area of Q-register q.  N
               should be greater than zero.

     n:Xq      Append n lines to Q-register q, where  n  is  a  signed
               integer with the same functions as n in the nXq command
               above.  The pointer is not moved.
               [not in TECO-8]

               The colon construct for appending to a  Q-register  can
               be used with all forms of the X command.

     ]q        Pop from the Q-register push-down list into  Q-register
               q.    Any   previous   contents  of  Q-register  q  are
               destroyed.  Both the numeric  and  text  parts  of  the
               Q-register  are loaded by this command.  The Q-register
               push-down list is a last-in  first-out  (LIFO)  storage
               area.   (See  section  3.3.3  for  a description of the
               push-down list.) This command does not  use  or  affect
               numeric values.  Numeric values are passed through this
               command transparently.  This allows macros  to  restore
               Q-registers and still return numeric values.
               [Not in TECO-8]

     :]q       Execute the ]q command and return a numeric  value.   A
               -1  indicates  that  there  was  another  item  on  the
               Q-register push-down list to be popped.  A 0  indicates
               that  the  Q-register  push-down  list  was  empty,  so
               Q-register q was not modified.
               [Not in TECO-8]

     *q        Save last-typed command string.  See section 4.2.

     Standard TECO                                             PAGE 83
     Q-registers


     Table 5-9B lists the commands which permit data to  be  retrieved
     from the Q-registers.


                TABLE 5-9B:  Q-REGISTER RETRIEVAL COMMANDS

     COMMAND        FUNCTION

     Qq        Use the integer stored in the number  storage  area  of
               Q-register q as the argument of the next command.

     nQq       Return the ASCII value  of  the  (n+1)th  character  in
               Q-register q.  The argument n must be between 0 and the
               Q-register's size minus 1.  If n is  out  of  range,  a
               value   of   -1   is  returned.   Characters  within  a
               Q-register are numbered the same way that characters in
               the text buffer are numbered.  The initial character is
               at character position  0,  the  next  character  is  at
               character  position 1, etc.  Therefore, if Q-register A
               contains "xyz", then 0QA will return the ASCII code for
               "x" and 1QA will return the ASCII code for "y".

     :Qq       Use the number of characters stored in the text storage
               area  of  Q-register  q  as  the  argument  of the next
               command.

     Gq        Copy  the  contents  of  the  text  storage   area   of
               Q-register q into the buffer at the current position of
               the buffer  pointer,  leaving  the  pointer  positioned
               after the last character copied.

     :Gq       Print  the  contents  of  the  text  storage  area   of
               Q-register  q on the terminal.  Neither the text buffer
               nor the buffer pointer is changed by this command.

     [q        Copy the contents of the numeric and text storage areas
               of  Q-register  q  into  the Q-register push-down list.
               This command does not alter either the numeric or  text
               storage  areas  of  Q-register  q.   It does not use or
               affect  numeric  values.   Numeric  values  are  passed
               through  this command transparently, allowing macros to
               save temporary Q-registers  and  still  accept  numeric
               values.   (Note,  however,  macros written to use local
               Q-registers, available in TECO-11, may be able to avoid
               saving  and  restoring Q-registers via the the pushdown
               list.) The command sequence [A ]B replicates  the  text
               string   and  numeric  value  from  Q-register  A  into
               Q-register B.
               [Not in TECO-8]

     Standard TECO                                             PAGE 84
     Q-registers


     Table 5-9C lists the commands which cause macros (strings  stored
     in Q-registers) to be executed.

     Macro invocations can be nested recursively;  the limit is set by
     the amount of pushdown storage TECO has available.

     In this table only,  a  distinction  is  made  between  a  global
     Q-register  name  (indicated below by "q") and a local Q-register
     name (indicated below by ".q").  Elsewhere in  this  manual,  "q"
     indicates either a global or local Q-register name.


                  TABLE 5-9C:  MACRO INVOCATION COMMANDS

     COMMAND        FUNCTION

     Mq        Execute the contents of the text storage area of global
               Q-register  q  as  a command string.  In TECO-11, a new
               set of local Q-registers is created before the macro is
               invoked.

     nMq       Execute the Mq command as above, using n as  a  numeric
               argument  for  the  first  command  contained in global
               Q-register  q.   In  TECO-11,  a  new  set   of   local
               Q-registers is created.

     m,nMq     Execute the Mq command as above, using m,n  as  numeric
               arguments  for  the  first  command contained in global
               Q-register  q.   In  TECO-11,  a  new  set   of   local
               Q-registers is created.

     :Mq       Execute the contents of the text storage area of global
               Q-register  q  as  a  command  string.  In TECO-11, the
               current set of local Q-registers remains  available  to
               the invoked macro;  no new set is created.

     n:Mq      Execute the :Mq command as above, using n as a  numeric
               argument  for  the  first  command  contained in global
               Q-register  q.   In  TECO-11,  no  new  set  of   local
               Q-registers is created.

     m,n:Mq    Execute the :Mq command as above, using m,n as  numeric
               arguments  for  the  first  command contained in global
               Q-register  q.   In  TECO-11,  no  new  set  of   local
               Q-registers is created.

     M.q       Execute the contents of the text storage area of  local
               Q-register  .q as a command string.  In TECO-11, no new
               set of local Q-registers is created.

     nM.q      Execute the M.q command as above, using n as a  numeric
               argument  for  the  first  command  contained  in local
               Q-register  .q.   In  TECO-11,  no  new  set  of  local

     Standard TECO                                             PAGE 85
     Q-registers


               Q-registers is created.

     m,nM.q    Execute the M.q command as above, using m,n as  numeric
               arguments  for  the  first  command  contained in local
               Q-register  .q.   In  TECO-11,  no  new  set  of  local
               Q-registers is created.

     :M.q      Execute the contents of the text storage area of  local
               Q-register  .q as a command string.  In TECO-11, no new
               set of local Q-registers is created.

     n:M.q     Execute the :M.q command as above, using n as a numeric
               argument  for  the  first  command  contained  in local
               Q-register  .q.   In  TECO-11,  no  new  set  of  local
               Q-registers is created.

     m,n:M.q   Execute the :M.q command as above, using m,n as numeric
               arguments  for  the  first  command  contained in local
               Q-register  .q.   In  TECO-11,  no  new  set  of  local
               Q-registers is created.

     Standard TECO                                             PAGE 86
     Arithmetic and Expressions


     5.10 ARITHMETIC AND EXPRESSIONS

     The numeric argument of a TECO command may consist  of  a  single
     integer,  any of the characters listed in Table 5-11, the numeric
     contents of any Q-register, or an arithmetic combination of these
     elements.   If  an arithmetic expression is supplied as a numeric
     argument, TECO will  evaluate  the  expression.   All  arithmetic
     expressions are evaluated from left to right without any operator
     precedence.  Parentheses may be used to override the normal order
     of  evaluation  of  an  expression.  If parentheses are used, all
     operations within the parentheses are performed, left  to  right,
     before  operations  outside  the parentheses.  Parentheses may be
     nested, in which  case  the  innermost  expression  contained  by
     parentheses  will  be  evaluated first.  Table 5-10A lists all of
     the  arithmetic  operators  that  may  be  used   in   arithmetic
     expressions.


                    TABLE 5-10A:  ARITHMETIC OPERATORS

     OPERATOR  EXAMPLE        FUNCTION

     +         +2=2      Ignored if used before the first term  in  an
                         expression.

     +         5+6=11    Addition, if used between terms.

     -         -2=-2     Negation, if used before the first term in an
                         expression.

     -         8-2=6     Subtraction, if used between terms

     *         8*2=16    Multiplication.  Used between terms.

     /         8/3=2     Integer division with loss of the  remainder.
                         Used between terms.

     &         12&10=8   Bitwise   logical   AND   of    the    binary
                         representation   of   the  two  terms.   Used
                         between the terms.

     #         12#10=14  Bitwise logical OR of the binary of  the  two
                         terms.  Used between the terms.

     ^_        5^_=-6    Unary  one's  complement.   Used   after   an
                         expression.   This  is  a  TECO  command that
                         complements its argument.  Strictly speaking,
                         it is not a unary operator.

     Standard TECO                                             PAGE 87
     Arithmetic and Expressions


            TABLE 5-10B:  CONVERSION AND RADIX CONTROL COMMANDS

     COMMAND        FUNCTION

     n=        This command causes the value of n to be output at  the
               terminal  in  decimal followed by a carriage return and
               line feed.  Decimal numeric conversion is signed.   For
               example, the unsigned number 65535 will output as -1 on
               TECO-11.  TECO's radix is unaltered.

     n==       This command causes the value of n to be output at  the
               terminal  in  octal  (base  8)  followed  by a carriage
               return and line  feed.   Octal  numeric  conversion  is
               unsigned.    For  example,  the  unsigned  number  8191
               (decimal) will output as 17777 on TECO-8.  TECO's radix
               is unaltered.

     n===      This command causes the value of n to be output at  the
               terminal   in  hexadecimal  (base  16)  followed  by  a
               carriage return and line feed.  Hexadecimal  output  is
               unsigned.  TECO's radix is unaltered.
               [TECO-11 only]

     n:=
     n:==
     n:===     These commands are equivalent to  n=,  n==,  and  n===,
               except  that  they leave the carriage positioned at the
               end of the output.

     ^O        <CTRL/O> (caret/O) causes all subsequent numeric  input
               to  be  accepted as octal numbers.  Numeric conversions
               using the \ or n\ commands will  also  be  octal.   The
               digits  8  and  9 become illegal as numeric characters.
               The octal radix will continue to be used until the next
               ^D command is executed or until TECO's radix is changed
               by an n^R command.
               NOTE:   On  TECO-10,  this  command  only  affects  the
               immediately following digit string.

     ^D        <CTRL/D> (caret/D) causes all subsequent numeric  input
               to be accepted as decimal numbers.  This is the initial
               setting.
               [Not in TECO-10]

     ^R        This command returns the binary value of TECO's current
               radix.
               [TECO-11 only]

     n^R       This command sets TECO's radix to the value of  n.   It
               is  currently  implemented only in TECO-11, where n may
               only be one of the values 8, 10,  or  16  (representing
               octal  mode,  decimal mode, or hexadecimal mode).  If n
               is not  one  of  these  values,  TECO's  radix  remains

     Standard TECO                                             PAGE 88
     Arithmetic and Expressions


               unchanged and the ?IRA error message is produced.

     \         A backslash  character  which  is  not  preceded  by  a
               numeric  argument  causes  TECO  to  evaluate the digit
               string  (if   any)   beginning   with   the   character
               immediately  following the buffer pointer and ending at
               the next character that is not valid  for  the  current
               radix.   The  value becomes the numeric argument of the
               next command.  The first character may be a digit or  +
               or  -.   As  the  backslash  command is evaluated, TECO
               moves the buffer  pointer  to  a  position  immediately
               following  the  digit  string.   If  there  is no digit
               string following the pointer, the result  is  zero  and
               the  pointer  position  remains  unchanged.   Except on
               TECO-8, the digits 8 and 9 will stop the evaluation  if
               TECO's current radix is octal.

     n\        The backslash command preceded by an  argument  inserts
               the  value  of  n  into  the text buffer at the current
               position of the pointer, leaving the pointer positioned
               after  the  last digit of the insertion.  The insertion
               is either  signed  decimal  (decimal  radix),  unsigned
               octal    (octal   radix),   or   unsigned   hexadecimal
               (hexadecimal radix).  Note that \ is a  "bidirectional"
               command.   n\  inserts  a  string into text while \ (no
               argument) returns a numeric result.

     Standard TECO                                             PAGE 89
     Special Numeric Values


     5.11 SPECIAL NUMERIC VALUES

     TECO maintains several internal variables which record conditions
     within  TECO.   The  variable  name  is equivalent to the current
     contents of the variable and may be entered as a numeric argument
     to  TECO  commands.   When  the  command is executed, the current
     value of the designated variable becomes the numeric argument  of
     the command.

     Some of the characters which stand for specific values associated
     with the text buffer have been introduced earlier in this manual.
     For example, the dot character (.), which represents the  current
     pointer  position,  may  be  used in the argument of a T command.
     The command ".,.+5T" causes the 5 characters following the buffer
     pointer  to  be  typed  out.   When this command is executed, the
     number of characters preceding the buffer pointer is  substituted
     in  each  case  for the "dot".  The addition is then carried out,
     and the command is executed as though it were of the form "m,nT".

     Table 5-11 lists all of the characters which have special numeric
     values.   Any of these characters may be used as numeric argument
     in place of the value it represents.


        TABLE 5-11:  CHARACTERS ASSOCIATED WITH NUMERIC QUANTITIES

     CHARACTER      FUNCTION

     B         Always equivalent to  zero.   Thus,  B  represents  the
               position preceding the first character in the buffer.

     Z         Equivalent  to  the  number  of  characters   currently
               contained  in  the  buffer.   Thus,  Z  represents  the
               position following the last character in the buffer.

     .         Equivalent to the  number  of  characters  between  the
               beginning of the buffer and the current position of the
               pointer.  Thus "." represents the current  position  of
               the pointer.

     H         Equivalent to the numeric  pair  "B,Z",  or  "from  the
               beginning  of  the buffer up to the end of the buffer."
               Thus, H represents the whole buffer.

     nA        Equivalent to the ASCII code for the .+n+1th  character
               in  the  buffer (that is, the character to the right of
               buffer pointer position .+n).  The  expression  -1A  is
               equivalent   to   the   ASCII  code  of  the  character
               immediately preceding the pointer and 0A is  equivalent
               to   the   ASCII  code  of  the  character  immediately
               following the pointer (the current character).  If  the
               character  position  referenced lies outside the bounds
               of the text buffer, this command returns a -1.

     Standard TECO                                             PAGE 90
     Special Numeric Values


     Mq        The Mq  command  (execute  the  contents  of  the  text
               storage area of Q-register "q" as a command string) may
               return a numeric value  if  the  last  command  in  the
               string returns a numeric value and is not followed by a
               <ESC>.

     Qq        Equivalent to the value stored in  the  number  storage
               area of Q-register q.

     :Qq       Equivalent to the number  of  characters  in  the  text
               storage area of Q-register q.
               [Not in TECO-8]

     \         Backslash is equivalent to the  numeric  value  of  the
               digit  string in the text buffer at the current pointer
               position,  interpreted  in  the  current  radix.    The
               pointer is moved to the end of the digit string.

     ^B        <CTRL/B> (caret/B) is equivalent to  the  current  date
               via the following equations:

               OS/8:      ^B = (((month*32)+day)*8)+((year-1970)&7)+k
                               where k = 4096 if year>1977
                               and k=0 otherwise
               RT-11:     ^B = (((month*32)+day)*32)+year-1972
               RSTS/E:    ^B = ((year-1970)*1000)+day within year
               RSX-11:    ^B = ((year-1900)*16+month)*32+day
               VAX/VMS:   ^B = ((year-1900)*16+month)*32+day
               TOPS-10:   ^B = (((year-1964)*12+month-1)*31+day-1)

     ^E        <CTRL/E> (caret/E) determines  whether  or  not  the  P
               command  (and related operations) append a form feed to
               the contents of the buffer on output.  If ^E is  -1,  a
               form  feed  is  appended;   if ^E is 0, no form feed is
               appended.

               Each time text is read into the text buffer  TECO  sets
               the ^E flag.  If the text read terminated due to a form
               feed (i.e., if  the  text  buffer  was  loaded  with  a
               "complete  page"),  ^E  is set to -1.  If the text read
               terminated because the buffer was  filled  to  capacity
               before a form feed was encountered or because there was
               no form feed (i.e., the text buffer was not loaded with
               a "complete page"), ^E is set to 0.

               In TECO-11, you can set the ^E flag's  value  directly,
               overriding  the  value  set  by  the most recent buffer
               read.  Be sure to use only values of 0  or  -1;   other
               values may cause unpredictable results.

     ^F        <CTRL/F> (caret/F) is equivalent to the  current  value
               of the console switch register.

     Standard TECO                                             PAGE 91
     Special Numeric Values


     n^F       n<CTRL/F> is the terminal number  plus  200000  (octal)
               for job n's terminal.  -1^F is the terminal number plus
               200000 (octal) for your job's terminal.  The result  is
               0  if  the  specified job is detached or if there is no
               such job.
               [TECO-10 only]

     ^H        <CTRL/H> (caret/H) is equivalent to the current time of
               day via the following equations:

               OS/8:      ^H = 0
               RT-11:     ^H = (seconds since midnight)/2
               RSTS/E:    ^H = minutes until midnight
               RSX-11:    ^H = (seconds since midnight)/2
               VAX/VMS:   ^H = (seconds since midnight)/2
               TOPS-10:   ^H = 60ths of a second since midnight
               (or 50ths of a second where 50 Hz power is used)

     ^N        <CTRL/N> (caret/N) is the end  of  file  flag.   It  is
               equivalent  to  -1  if  the  file open on the currently
               selected input stream is  at  end  of  file,  and  zero
               otherwise.

     ^S        <CTRL/S> (caret/S) is equivalent to the negative of the
               length  of  the  last  insert,  string found, or string
               inserted with a "G" command, whichever  occurred  last.
               To back up the pointer to the start of the last insert,
               string found, etc., type "^SC".
               [Not in TECO-8]

     ^T        <CTRL/T> (caret/T) is equivalent to the ASCII code  for
               the  next  character  typed  at the terminal.  Every ^T
               command executed causes TECO to pause  and  accept  one
               character  typed  at  the  terminal.   See  the ET flag
               description (section 5.16) for variations.

     :^T       Reads and decodes  the  next  keystroke  typed  at  the
               terminal.   The  decoded  keystroke  is  returned  in a
               manner  similar  to  that  used  for  immediate  ESCape
               sequence  commands  (see section 4.4), i.e., via <type>
               and <value> codes, as follows:
                    <type> 0   Normal character,
                                 <value> is ASCII value

                    <type> 1   Control character
                                 (except ESCape or CSI);
                                 <value> is ASCII value of
                                 control char.
                                 A typed <CR> yields
                                 <type> 1 <value> 13,
                                 and subsequent ^T or :^T
                                 does not return a <LF>.

     Standard TECO                                             PAGE 92
     Special Numeric Values


                    <type> 2   Same as immed ESC seq <type> 0
                    <type> 3   Same as immed ESC seq <type> 1
                    <type> 4   Same as immed ESC seq <type> 2
                    <type> 5   Same as immed ESC seq <type> 3
               [TECO-11 only]

     ^Y        <CTRL/Y> (caret/Y) is equivalent to ".+^S,.",  the  n,m
               numeric argument spanning the text just searched for or
               inserted.  This value  may  be  used  to  recover  from
               inserting  a string in the wrong place.  Type "^YXSFR`"
               to store the string in Q-register S and remove it  from
               the  buffer.   You can then position the pointer to the
               right place and type "GS" to insert the string.
               [TECO-11 only]

     ^Z        <CTRL/Z> (caret/Z) is equivalent  to  the  total  space
               occupied  by  text  in  the  Q-registers (including the
               command line currently being executed).
               [TECO-11 only]

     ^^x       The combination of the Control-caret (double  caret  or
               double   up-arrow)   followed   by   any  character  is
               equivalent to the value of  the  ASCII  code  for  that
               character.    The  "x"  in  this  example  may  be  any
               character that can be typed in to TECO.

     Standard TECO                                             PAGE 93
     Special Numeric Values


                                 MODE CONTROL FLAGS

     The following mode control flags return numeric values.  The  use
               of these flags is described below in section 5.16.

     ED        Equivalent to the current value of the edit level flag.

     EH        Equivalent to the current value of the help level flag.

     EO        Equivalent to the version number of the version of TECO
               which  is  currently  being run.  This manual describes
               TECO-11 Version  40,  TECO-8  Version  7,  and  TECO-10
               Version 3.

     ES        Equivalent  to  the  current  value   of   the   search
               verification flag.
               [Not in TECO-8]

     ET        Equivalent to the current value of the type out control
               flag.

     EU        Equivalent to the current value of the upper/lower case
               flag.

     EV        Equivalent to the current  value  of  the  edit  verify
               flag.
               [TECO-11 only]

     ^X        <CTRL/X> (caret/X) is equivalent to the  current  value
               of the search mode flag.
               [Not in TECO-8]

     Standard TECO                                             PAGE 94
     Command Loops


     5.12 COMMAND LOOPS

     You can cause a command string to be executed any number of times
     by placing the command string within angle brackets and preceding
     the brackets with a numeric argument designating  the  number  of
     iterations.   Iterated  command strings are called command loops.
     Loops may be nested so that one  command  loop  contains  another
     command  loop,  which, in turn, contains other command loops, and
     so on.  The maximum depth to which command loops may be nested is
     determined   by   the  size  of  TECO's  push-down  list  (system
     dependent), but is always greater than 10.

     The general form of the command loop is:

                             n<command string>

     where "command string" is the sequence of commands to be iterated
     and  n is the number of iterations.  If n is not supplied then no
     limit is placed on the number of iterations.  If n is 0  or  less
     than  0  then  the  iteration  is  not  executed at all;  command
     control skips to the closing angle bracket.  If n is greater than
     0, then the iteration is performed n times.

     Search commands inside command loops are treated specially.  If a
     search  command  which  is  not  preceded  by a colon modifier is
     executed within a command loop and the search  fails,  a  warning
     message  is  printed  [on  TECO-11],  the  command loop is exited
     immediately and the command following the right angle bracket  of
     the  loop  is  the next command to be executed.  If an unmodified
     search command in a command loop is  immediately  followed  by  a
     semicolon,  it  is  treated as if it were a colon-modified search
     (see section 5.13).

     Standard TECO                                             PAGE 95
     Branching Commands


     5.13 BRANCHING COMMANDS

     TECO provides an  unconditional  branch  command  and  a  set  of
     conditional  execution  commands.   To  branch  within  a command
     string, you must be able to name  locations  inside  the  string.
     TECO permits location tags of the form:

                                   !tag!

     to be placed between any two commands in a command  string.   The
     name "tag" will be associated with this location when the command
     string is  executed.   Tags  may  contain  any  number  of  ASCII
     characters  and  any character except an exclamation mark.  (When
     using the @ form  of  this  command,  any  character  except  the
     delimiter is legal.) Since tags are ignored by TECO except when a
     branch command references the tagged location, they may  also  be
     used as comments within complicated command strings.

     The unconditional branch command is the O command which  has  the
     form:

                                   Otag`

     where "tag" is a location named elsewhere in the  command  string
     and  "`" signifies a <DELIM>.  When an O command is executed, the
     next command to be executed will be the one that follows the  tag
     referenced   by  the  O  command.   Command  execution  continues
     normally from this point.

     Use of the O command is subject to two restrictions.   First,  if
     an  O  command  is  stored  in  a Q-register as part of a command
     string which  is  to  be  executed  by  an  M  command,  the  tag
     referenced by the O command must reside in the same Q-register.

     Second, an O command which is  inside  a  command  loop  may  not
     branch to a tagged location preceding the command loop.  However,
     it is always possible to branch  out  of  a  command  loop  to  a
     location  which  follows  the command loop and then branch to the
     desired tag.

     The string argument in the O command has the same format  as  the
     string  arguments  in  the  search  and E commands.  String build
     characters such as ^EQq can be  embedded  within  the  string  in
     TECO-11.   Also,  in  TECO-11  and  TECO-10, the O command may be
     @-sign modified.  In that case, the syntax of the  command  would
     be  @O/tag/ where / represents any delimiting character that does
     not appear within the tag.

     Branching into a conditional poses  no  problems,  but  branching
     into a command loop will causes unpredictable results.

     Although tags may contain any sequence of ASCII characters,  good
     programming  practice  dictates  that  tags  should  not  contain

     Standard TECO                                             PAGE 96
     Branching Commands


     unusual characters (such as space, comma, ESCAPE, etc.) and  that
     they  should  be  mnemonic  for  the  piece of code to which they
     refer.

     There are many other  branching  commands.   Most  of  these  are
     considerably  faster  than  the  O  command  and  should  be used
     wherever convenient.  They are all described in the table below.

                      TABLE 5-13: BRANCHING COMMANDS

     COMMAND        FUNCTION

     Otag`     This  command  causes  TECO  to  branch  to  the  first
               occurrence  of the specified label (tag) in the current
               macro level.  In TECO-8 and TECO-11, branching  to  the
               left  of  the  start  of  the  current iteration is not
               permitted, and this  command  will  only  look  for  an
               occurrence  of the specified tag following the < of the
               current iteration, if you are in an iteration.  In  any
               case, branching out of an iteration is poor programming
               practice.   Command  execution  resumes  at  the  first
               character after the delimiter terminating the specified
               tag.  Using this syntax, any character except <ESC>  is
               permitted  in  the tag specification.  The usual string
               build characters are permitted when specifying the tag.

     @O/tag/   Equivalent to Otag` except that a delimiter (shown here
               as  /) is used before and after the specified tag.  Any
               character other than that delimiter is permitted inside
               the   tag.   The  usual  string  build  characters  are
               permitted when specifying the tag.
               [Not in TECO-8]

     nOtag0,tag1,tag2,...`
               This command causes TECO to branch to the tag specified
               by  the  nth  tag in the accompanying list.  The string
               argument to this command consists of a sequence of tags
               separated   by   commas.   The  tags  may  contain  any
               characters other than comma or  <ESC>;   however,  good
               programming  practice  suggests  that  the  tags should
               consist only of letters and digits.  There must  be  no
               intervening spaces since these would be considered part
               of the tag.  If n is out of range, or if  n  selects  a
               null  tag,  then  command  execution continues with the
               first command following the <DELIM> that delimits  this
               command.  (A null tag would be signified in the list by
               two adjacent commas.)
               [TECO-11 only]

     n@O/tag0,tag1,tag2,.../
               Same as the preceding command except that the  list  of
               tags  is  bracketed  by  a delimiter shown here as "/".
               The delimiter can be any character that does not appear

     Standard TECO                                             PAGE 97
     Branching Commands


               within  the  list  of tags.  In particular, using comma
               for the delimiter would not be very useful.
               [TECO-11 only]

     ;         This command causes TECO to branch out of  the  current
               iteration,  if  the  immediately  preceding  search (or
               search and replace)  command  failed.   In  that  case,
               control resumes at the character following the matching
               > at the end of the current iteration.   On  the  other
               hand,   if  the  preceding  search  succeeded,  command
               execution continues with the character following the ;.
               If  this  command  is  encountered  from  outside of an
               iteration (in the current macro level), then  the  ?SNI
               error message is issued.

     n;        This command causes TECO to branch out of  the  current
               iteration if the value of n is greater than or equal to
               0.  In that case,  command  execution  resumes  at  the
               character  following  the  matching > at the end of the
               current iteration.  On the other hand,  if  n  is  less
               than  0, command execution continues with the character
               following the ;.  If this command is  encountered  from
               outside  of  an iteration (in the current macro level),
               then the ?SNI error message is issued.

     :;        This command causes TECO to branch out of  the  current
               iteration  if  the  immediately  preceding  search  (or
               search and replace) command succeeded.  In  that  case,
               control resumes at the character following the matching
               > at the end of the current iteration.   On  the  other
               hand, if the preceding search failed, command execution
               continues with the character following the ;.  If  this
               command is encountered from outside of an iteration (in
               the current macro level), then the ?SNI  error  message
               is issued.
               [TECO-11 only]

     n:;       This command causes TECO to branch out of  the  current
               iteration  if  the  value of n is less than 0.  In that
               case,  command  execution  resumes  at  the   character
               following  the  matching  >  at  the end of the current
               iteration.  On the other hand, if n is greater than  or
               equal  to  0,  command  execution  continues  with  the
               character  following  the  ;.   If  this   command   is
               encountered  from  outside  of  an  iteration  (in  the
               current macro level), then the ?SNI  error  message  is
               issued.
               [TECO-11 only]

     '         This "command" is actually part of the syntax  of  TECO
               conditionals.   It  has  no  affect if "executed" other
               than to signify termination of the current  conditional
               level.   If  an  argument is specified to this command,

     Standard TECO                                             PAGE 98
     Branching Commands


               the result is not  defined.   (Arguments  pass  through
               this command on TECO-11.) Conditionals are described in
               section 5.14.

     |         This "command" is actually part of the syntax  of  TECO
               conditionals.  If executed, it causes control to branch
               to the  end  of  the  conditional.   Command  execution
               resumes  with  the  character following the ' that ends
               the current conditional  with  the  ELSE  clause  being
               skipped.

     >         This "command" is actually part of the syntax  of  TECO
               iterations.   If  executed,  it causes TECO to bump the
               current iteration count by 1 and test  to  see  if  the
               resulting count is equal to the maximum count permitted
               for the iteration (specified as an argument before  the
               matching  <).   If the iteration count has not expired,
               then control returns to the command following the <  at
               the   beginning  of  the  current  iteration.   If  the
               iteration has expired, then command execution continues
               with  the  character following this >.  If this command
               is encountered outside  of  an  iteration  (within  the
               current  macro  level), then the ?BNI error message (or
               its equivalent) is issued.

     F>        This command causes TECO to branch (flow) to the end of
               the   current   iteration.   TECO  effectively  resumes
               execution at the matching >.  The  iteration  count  is
               tested  as  usual.   If  it  has  not  expired, control
               returns back to the start of  the  iteration  with  the
               count  having  been incremented by 1.  If the count was
               up, the iteration is exited and control continues  with
               the  first  command  after  the  >.  If this command is
               encountered outside of an iteration, it  has  the  same
               effect as the <DELIM><DELIM> command.
               [TECO-11 only]

     F<        This command causes TECO to branch (flow) to the  start
               of  the  current  iteration.   TECO effectively resumes
               execution at the first command following the <  at  the
               beginning  of  the  current  iteration.   The iteration
               count is not  affected.   If  this  command  is  issued
               outside  of an iteration, it causes TECO to branch back
               to the start of the  current  command  string  (in  the
               current macro level).
               [TECO-11 only]

     F'        This command causes TECO to branch (flow) to the end of
               the  current  conditional.   TECO  effectively  resumes
               execution at the first command following the '  at  the
               end  of the current conditional.  Numeric arguments are
               eaten up by this command.  If this  command  is  issued
               while  not  in  a  conditional,  the ?MAP error (or its

     Standard TECO                                             PAGE 99
     Branching Commands


               equivalent) is issued.
               [TECO-11 only]

     F|        This command causes TECO to branch (flow) to  the  else
               clause  of  the  current conditional.  TECO effectively
               resumes execution at the first command following the  |
               at  the end of the current THEN clause.  If the current
               conditional has no ELSE clause, or if an unmatched ' is
               encountered before an unmatched |, then control resumes
               at the command following the ' .  Numeric arguments are
               eaten  up  by  this command.  If this command is issued
               while not in a conditional,  the  ?MAP  error  (or  its
               equivalent) is issued.  Well-structured programs should
               not need to use this command.
               [TECO-11 only]

     $$        The <ESC><ESC> command causes TECO  to  exit  from  the
               current  macro  level.   If this command is issued from
               top level (not from within a macro), then  the  command
               string  execution  is  terminated  and  TECO returns to
               prompt level.  Note that the second  <ESC>  must  be  a
               true  ESCape and may not be a ^[.  Also, note that both
               ESCapes must be true TECO commands and not part of  the
               syntax  of  some  previous command.  That is, the first
               <ESC> does not count if it is the delimiting ESCape  of
               a string.  Finally, note that these must be real ESCape
               characters,  and  not   the   user-designated   <DELIM>
               character  (which  TECO  understands  as an ESCape only
               when typed at the console).

     n$$       This command causes TECO to exit from the current macro
               level,  returning  the number n as a value.  This value
               will be used as  the  numeric  argument  to  the  first
               command following the macro call.

     m,n$$     This command causes TECO to exit from the current macro
               level,  returning  the  pair  of  values  m  and  n  as
               arguments to the  first  command  following  the  macro
               call.  Good programming practice dictates that all ways
               of exiting a macro return the same number of arguments.

     ^C        The <CTRL/C> (Caret-C) command when executed as a  TECO
               command,  causes  command execution to stop and control
               return to TECO's  prompt.   No  clean-up  of  push-down
               lists, flag settings, etc.  is done.  This command lets
               a macro abort TECO's command execution.
               [On TECO-8 and TECO-10, this command causes control  to
               return to the operating system.]
               [On TECO-11, this  command  returns  to  the  operating
               system if executed from the top level.]
               Consult the appendices for specific details  concerning
               your operating system.

     Standard TECO                                            PAGE 100
     Branching Commands


     ^C<CTRL/C>
               This command causes TECO to unconditionally  abort  and
               control  exits  from  TECO.   Control  returns  to  the
               operating system.  The second <CTRL/C> must be  a  true
               <CTRL/C> and may not be a Caret-C.

     Standard TECO                                            PAGE 101
     Conditional Execution Commands


     5.14 CONDITIONAL EXECUTION COMMANDS

     All conditonal execution commands are of the form:

                           n"X command-string '
        or
              n"X then-command-string | else-command-string '

     In the first form of the command, "n" is a  numeric  argument  on
     which  the  decision  is  based,  "X"  is  any of the conditional
     execution commands listed in table 5-14, and "command string"  is
     the  command  string  which  will be executed if the condition is
     satisfied.   The  numeric  argument   is   separated   from   the
     conditional  execution  command  by  a  double  quote (") and the
     command string is terminated with  an  apostrophe  (').   If  the
     condition  is  not  satisfied,  the  command  string  will not be
     executed;  execution will continue with the first  command  after
     the apostrophe.

     In the second form  of  the  command,  two  command  strings  are
     specified.   The  first  one  is  executed  if  the  condition is
     satisfied and the second is executed  if  the  condition  is  not
     satisfied.   Only  one  of  the command strings will be executed.
     After execution of the appropriate command string,  control  will
     continue  with the first command after the apostrophe (unless the
     command string caused a branch out of the conditional to  occur),
     since  execution  of  the vertical bar command (|) causes TECO to
     scan to the next matching apostrophe.

     Conditional commands are similar to the  IF-THEN-ELSE  constructs
     that you find in other structured programming languages, although
     none can match the brevity and elegance of TECO's implementation.
     Nonetheless,   you   must  use  these  facilities  wisely.   Good
     programming practice dictates that a branch into the range  of  a
     conditional (from outside that range) should not occur.

     Conditional execution commands may be nested in the  same  manner
     as  iteration  commands.  That is, the command string which is to
     be executed if the condition on n is met may contain  conditional
     execution   commands,   which   may,  in  turn,  contain  further
     conditional execution commands.


                TABLE 5-14:  CONDITIONAL EXECUTION COMMANDS

     COMMAND        FUNCTION

     n"A       Execute the following command string if  n  equals  the
               ASCII  code for an alphabetic character (upper or lower
               case A to Z).

     n"C       Execute the following command string if n is the  ASCII
               code  of  any  character  that is a symbol constituent.

     Standard TECO                                            PAGE 102
     Conditional Execution Commands


               This is usually one of the upper or lower case  letters
               A  to Z, one of the digits 0 to 9, or period, or dollar
               sign, but may include  additional  characters  on  some
               operating systems.  Consult the appropriate appendix.

     n"D       Execute the following command string if  n  equals  the
               ASCII code for a digit (0 to 9).

     n"E       Execute the following command string if n is  equal  to
               zero.

     n"F       Execute the following command string  if  n  is  FALSE.
               Equivalent to n"E.

     n"G       Execute the following command string if  n  is  greater
               than zero.

     n"L       Execute the following command string if n is less  than
               zero.

     n"N       Execute the following command string if n is not  equal
               to zero.

     n"R       Execute the following command string if  n  equals  the
               ASCII  code  for an alphanumeric (upper or lower case A
               to Z or 0 to 9).

     n"S       Execute  the  following  command   string   if   n   is
               SUCCESSFUL.  Equivalent to n"L.

     n"T       Execute the following command  string  if  n  is  TRUE.
               Equivalent to n"L.

     n"U       Execute  the  following  command   string   if   n   is
               UNSUCCESSFUL.  Equivalent to n"E.

     n"V       Execute the following command string if  n  equals  the
               ASCII code for a lower case alphabetic character (lower
               case A to Z).
               [Not in TECO-8]

     n"W       Execute the following command string if  n  equals  the
               ASCII  code  for  an  upper  case  alphabetic character
               (upper case A to Z).
               [Not in TECO-8]

     n"<       Identical to n"L

     n">       Identical to n"G

     n"=       Identical to n"E

     Standard TECO                                            PAGE 103
     Retrieving Environment Characteristics


     5.15 RETRIEVING ENVIRONMENT CHARACTERISTICS

     The following TECO commands return values of  interest  to  users
     who  want  information  about  their  current  job, the operating
     system, their terminal, etc.

     All negative EJ commands return  an  operating  system  dependent
     value.   Consult  the  appendices  for  operating  system  unique
     commands.


            TABLE 5-15A: RETREIVING ENVIRONMENT CHARACTERISTICS

     COMMAND        FUNCTION

     -1EJ      Return a number representing the computer and operating
               system  upon  which  TECO  is  currently running.  This
               value  has  the  form  256m+n  where  m  is  a   number
               representing  the  computer  in  use  and n is a number
               representing the  operating  system  that  is  running.
               Current values of m and n are:

                         Computer (m)        Operating System (n)

                         0         PDP-11    0    RSX-11D
                                             1    RSX-11M
                                             2    RSX-11S
                                             3    IAS
                                             4    RSTS/E
                                             5    VAX/VMS
                                                  (compatibility mode)
                                             6    RSX-11M+
                                             7    RT-11
                         1         PDP-8     0    OS/8
                         2         DEC-10    0    TOPS-10
                         3         DEC-20    0    TOPS-20
                         4         VAX-11    0    VAX/VMS
                                                  (native mode)

     0EJ       Returns  a  value  equal  to  your  job   number.    On
               single-user systems, this is always a 0.

     1EJ       Returns a value equal to your console  keyboard  number
               (the  keyboard  you  detached  from  if you are running
               detached).  On single-terminal systems, this is  always
               a 0.

     2EJ       Returns a value equal to your operating  system's  user
               identification  number.   This  may be called your UIC,
               PPN, Group,  etc.   under  various  operating  systems.
               Consult the appendices for more information.

     Standard TECO                                            PAGE 104
     Retrieving Environment Characteristics


                    TABLE 5-15B: SETTING ENVIRONMENT INFORMATION

     n,1EJ     Set the terminal number to receive output.   This  will
               not  affect  terminal  input.   Your  job  will  remain
               attached to, or detached from, your terminal, whichever
               it was before.  Output will only occur if the specified
               terminal is ASSIGNed with a monitor ASSIGN command (you
               may  ^C,  issue  that command and continue) and if your
               job has POKE privileges.  This command  also  sets  the
               terminal  to  be  reattached  if  the  set  detach flag
               (64&ET) is cleared.  The reattaching operation requires
               [1,2] or JACCT privileges.
               [TECO-10 only]

     n,2EJ     Sets your [p,pn] to n where n has the  same  format  as
               the  number  returned  by the 2EJ command.  Issuance of
               this command requires the appropriate privileges.
               [TECO-10 only]

     Standard TECO                                            PAGE 105
     Mode Control Flags


     5.16 MODE CONTROL FLAGS

     TECO has flags which control various aspects  of  its  operation.
     You  can  find  a flag's current setting by executing its command
     name without an argument;  the current setting  of  the  flag  is
     returned  as  a  value.  A flag may be set to a specific value by
     executing its command name preceded by a numerical argument;  the
     flag is set to the value of the argument.

     The following table describes the commands  that  set  and  clear
     flags;  <flag> represents any of the flags listed below.


                  TABLE 5-16A: FLAG MANIPULATION COMMANDS

     <flag>         Return value of flag.

     n<flag>        Set value of flag to n.

     m,n<flag>      In the flag, turn off those bits  specified  by  m
                    and turn on those bits specified by n.

     0,n<flag>      Turn on the bits in the flag specified by n.

     m,0<flag>      Turn off the bits in the flag specified by m.


     The flags have the following functions:


                     TABLE 5-16B:  MODE CONTROL FLAGS

     COMMAND             FUNCTION

     ED        The edit level flag, a bit-encoded word  that  controls
               TECO's  behavior  in various respects.  Any combination
               of the individual bits may be set as the user sees fit.
               The bits have the following functions:

               ED&1      Allow caret (^) in search strings.   If  this
                         bit  is clear, a caret (^) in a search string
                         modifies the immediately following  character
                         to become a control character.  When this bit
                         is set, a caret in a search string is  simply
                         the  literal  character  caret.   If  you are
                         editing  a  file  that  contains  many  caret
                         characters  (e.g.,  a  RUNOFF  file with case
                         control), you will  want  to  set  this  bit.
                         (For  control of upper/lower case matching in
                         search strings, see the ^X flag.)

               ED&2      Allow all Y and _ commands.  If this  bit  is
                         set,  the  Y (Yank) command and _ (underscore

     Standard TECO                                            PAGE 106
     Mode Control Flags


                         or backarrow) command work unconditionally as
                         described  earlier  in the manual.  If clear,
                         the behavior of the  Y  and  _  commands  are
                         modified  as  follows:   If an output file is
                         open and text exists in the text buffer,  the
                         Y  or _ command will produce an error message
                         and the command will be aborted  leaving  the
                         text  buffer  unchanged.   Note  that  if  no
                         output file is open the Y and _ commands  act
                         normally.  Furthermore, if the text buffer is
                         empty the Y command can be used to bring in a
                         page of text whether or not an output file is
                         open (HKY will always work).  The  _  command
                         will  succeed  in  bringing  one page of text
                         into an empty text buffer but  will  fail  to
                         bring  in  successive pages if an output file
                         is open.

               ED&4      When this bit is  clear,  TECO  will  try  to
                         expand  memory  as much as it can in order to
                         try to fit  entire  pages  into  memory  when
                         requested  to  do  so.   If  this bit is set,
                         arbitrary memory expansion  will  not  occur.
                         In that case, TECO will expand memory only on
                         the A command and not  on  the  Y,  P,  or  N
                         commands.   This bit is always set in TECO-10
                         and has  no  significance  in  TECO-8  or  in
                         TECO-11 on RT-11.

               ED&8      Reserved for future use by TECO-8.

               ED&16     Allow failing searches to preserve  dot.   If
                         this  bit  is  set,  then  whenever  a search
                         fails, the  original  location  of  the  text
                         buffer  pointer  will  be preserved.  If this
                         bit is clear, then  failing  searches  (other
                         than  bounded searches) leave the text buffer
                         pointer at  pointer  position  0  after  they
                         fail.
                         [not in TECO-8]

               ED&32     Enable  immediate  ESCape-sequence  commands.
                         If  this  bit  is set, TECO will recognize an
                         ESCape-sequence key pressed immediately after
                         the   prompting   asterisk  as  an  immediate
                         command.  See section 4.4 for  a  description
                         of immediate ESCape-sequence commands.

                         If this bit is clear (the default case), TECO
                         will  treat  an  ESCape coming in immediately
                         after the asterisk prompt as a  <DELIM>  That
                         is,   TECO   will   hear   a  discrete  <ESC>
                         character:  an ESCape sequence will therefore

     Standard TECO                                            PAGE 107
     Mode Control Flags


                         be treated not as a unified command, but as a
                         sequence of characters.
                         [TECO-11 only]

               ED&64     Only move dot by one on  multiple  occurrence
                         searches.   If this bit is clear, TECO treats
                         nStext` exactly as n<1Stext`>.  That is, skip
                         over  the  whole  matched  search string when
                         proceeding to  the  nth  search  match.   For
                         example,  if  the  text  buffer contains only
                         A's, the command 5SAA` will complete with dot
                         equal  to ten (10).  If this bit is set, TECO
                         increments dot by one each search match.   In
                         the above example, dot would become five (5).
                         [TECO-11 only]

               ED&128    Automatic refresh inhibit.  If scroll mode is
                         enabled  (that  is, if 7:W is non-zero), TECO
                         normally refreshes the  text  buffer  display
                         just  before  printing its * prompt.  Setting
                         the 128 bit in  ED  inhibits  this  automatic
                         refresh.   (Inhibiting  the automatic refresh
                         may  be  useful  when  running  over  a  slow
                         terminal  line;   see  also  the ^W immediate
                         command.)
                         [TECO-11 only]

               The initial value of  ED&1  is  system  dependent  (See
               appendices).   The  initial  value of the other bits in
               the ED flag is 0.

     EE        This flag is initially zero, and (unless  the  8192  ET
               bit  is  set)  TECO  recognizes  only the ESCape as its
               <DELIM> character from the console.  If it  is  desired
               to  use  another  character  as an ESCape surrogate (as
               when working from a terminal lacking  an  ESCape  key),
               the  ASCII  value of that other character may be set in
               the EE flag.  Note that when  an  ESCape  surrogate  is
               set,  the  designated  character  (when  typed  at  the
               console) is received by  TECO  as  an  ESCape  --  that
               character  is  no  longer  directly  available  at  the
               keyboard.  When  an  ESCape  surrogate  is  active,  an
               ESCape  received  by  TECO echos as accent grave;  when
               none is active, an ESCape received  by  TECO  echos  as
               dollar  sign.  This feature is provided for the benefit
               of newer terminals which lack an ESCape  key.   (8192ET
               and  96EE both set ` as ESCape surrogate.  EE, however,
               can be used to designate a character other than  accent
               grave.)
               [RSTS/E only]

     EH        The help level flag, which  controls  the  printing  of
               error  messages  and  failed commands.  (See also the /

     Standard TECO                                            PAGE 108
     Mode Control Flags


               command.)

               EH&3      The low two bits of EH (value range 0 through
                         3)   control   the  printing  of  TECO  error
                         messages as follows  (assuming  the  low  two
                         bits have value m):

                         If m is equal to 1, error messages are output
                         in  abbreviated form ("?XXX").  If m is equal
                         to 2, error messages  are  output  in  normal
                         form  ("?XXX  Message").  If m is equal to 3,
                         error messages are output in long or "War and
                         Peace"   form,   that   is,  a  paragraph  of
                         informative material is typed  following  the
                         normal   form   of  the  error  message.   In
                         TECO-11, m=3 is implemented only on  VAX/VMS.
                         (See  section  G.13 for a description of HELP
                         facilities available on  VAX/VMS.)  In  other
                         TECO-11's, case m=3 is equivalent to m=2.

               EH&4      If this bit of EH is set, the failing command
                         is  also  output  up  to  and  including  the
                         failing character in the command followed  by
                         a  question mark.  (Just like TECO's response
                         to the typing of a question mark  immediately
                         after an error.) This bit is not supported by
                         TECO-10.

               The initial  value  of  the  EH  flag  is  0  which  is
               equivalent to a value of 2.

     EO        Setting the value of the EO flag to n  allows  features
               that were peculiar to that version of TECO to work.
               [TECO-10 only]

     ES        The search verification flag, which controls  the  text
               typed out after searches.

               If n  is  equal  to  0,  nothing  is  typed  out  after
               searches.   If  n  is -1, the current line is typed out
               when a successful search  at  top  level  is  completed
               (i.e.,  a  V  command  is done automatically).  If n is
               between 1 and 31, the current line is typed out with  a
               line  feed  immediately  following  the position of the
               pointer to identify its position.  If n is  between  32
               and  126,  the current line is typed out with the ASCII
               character corresponding to the value of  n  immediately
               following  the  position of the pointer to identify its
               position.  If you want to see more  than  one  line  of
               type  out,  use the form m*256+n.  The n is the same as
               above.  The m is the number  of  lines  of  view.   For
               example, 3*256+^^!  would give two lines on either side
               of  the  found  line,  and  the  found  line  with  the

     Standard TECO                                            PAGE 109
     Mode Control Flags


               character  "!"  at the pointer's position.  The ES flag
               does not apply to searches executed  inside  iterations
               or macros;  lines found inside iterations or macros are
               never typed out.
               [Not in TECO-8]

               The initial value of ES is 0.

     ET        The ET flag is a bit-encoded  word  controlling  TECO's
               treatment  of the console terminal.  Any combination of
               the individual bits may be set.  The bits  provide  the
               following functions, when set:

               ET&1      Type out in image  mode.   Setting  this  bit
                         inhibits  all of TECO's type out conversions.
                         All characters are  output  to  the  terminal
                         exactly  as  they  appear in the buffer or ^A
                         command.   For  example,  the   changing   of
                         control characters into the "caret/character"
                         form, and the conversion  of  <ESCAPE>  to  `
                         (accent  grave)  or  to  $  (dollar sign) are
                         suppressed.  This mode is useful for  driving
                         displays.   It  should  be used with caution,
                         especially if you are talking to TECO over  a
                         dial-up line.

               ET&2      Process  DELETEs  and  <CTRL/U>s  in  "scope"
                         mode.   Scope mode processing uses the cursor
                         control features of  CRT  type  terminals  to
                         handle character deletion by actually erasing
                         characters from the screen.

               ET&4      Read lower case.  TECO normally converts  all
                         lower  case  alphabetics  to  upper  case  on
                         input.  Setting this bit  causes  lower  case
                         alphabetics  to be input as lower case.  TECO
                         commands and file specifiers may be typed  in
                         either  upper or lower case.  For the purpose
                         of searches, however, upper  and  lower  case
                         may be treated as different characters.  (See
                         ^X flag).

               ET&8      Read without  echo  for  ^T  commands.   This
                         allows  data  to  be  read  by the ^T command
                         without having the  characters  echo  at  the
                         terminal.   Normal command input to TECO will
                         echo.

               ET&16     Cancel <CTRL/O> on type  out.   Setting  this
                         bit will cancel any outstanding <CTRL/O> when
                         the next type out  occurs.   After  TECO  has
                         canceled  the <CTRL/O>, it will automatically
                         clear the bit.

     Standard TECO                                            PAGE 110
     Mode Control Flags


               ET&32     Read with  no  wait.   This  enables  the  ^T
                         command  to  test if a character is available
                         at the user terminal.   If  a  character  has
                         been  typed,  ^T  returns  the  value  of the
                         character as always.   If  no  character  has
                         been typed, ^T immediately returns a value of
                         -1 and execution  continues  without  waiting
                         for a character.

               ET&64     Detach flag (See appendices).

               ET&128    "Abort-on-error" bit.   Initially  set,  when
                         TECO  starts  up;   cleared  each  time  TECO
                         issues its asterisk prompt.  When this bit is
                         set:    1) all   informational  messages  are
                         supressed,   2) any   <CTRL/C>   causes   the
                         immediate  termination  of  TECO,  and 3) any
                         error causes the termination  of  TECO  after
                         the error message is printed.

               ET&256    If this bit is set, all lines output  to  the
                         terminal  are  truncated  to  the  terminal's
                         width  if  needed.   (RSTS/E,   RSX-11,   and
                         VAX/VMS  only.  On VAX/VMS, this bit reflects
                         and can change  the  state  of  the  terminal
                         characteristic  WRAP/NOWRAP;   TECO  restores
                         the terminal characteristic to  its  original
                         state upon exit.)

               ET&512    If this bit is set, the scope "WATCH" feature
                         of  TECO  is  present  and your terminal is a
                         scope type terminal.  This bit is a read-only
                         bit;   its  state  cannot  be  altered.  (See
                         Section 5.17.)

               ET&1024   If this bit is set, the refresh scope "WATCH"
                         feature  of  TECO  is  present  and a refresh
                         scope is available.  This bit is a  read-only
                         bit;   its  state  cannot  be  altered.  (See
                         Section 5.17.)

               ET&4096   This bit reflects and can change the state of
                         the  terminal  characteristic  (maintained by
                         the operating system) recording  whether  the
                         terminal  is  capable  of  handling eight-bit
                         character codes.  Upon entry  to  TECO,  this
                         bit  reflects  the characteristic as recorded
                         with the operating system at that  time.   If
                         you  change this bit, the operating system is
                         directed  to  change  its  recording  of  the
                         characteristic to match.

                         Because the data manipulated (edited) by TECO

     Standard TECO                                            PAGE 111
     Mode Control Flags


                         can  consist  of all 256 possible byte codes,
                         the way data characters are displayed  (typed
                         out) at the console varies depending upon the
                         setting of the 4096 ET bit.

                         If  the  bit  is  clear  (meaning  that  TECO
                         understands your terminal to be 7-bit), valid
                         DEC multi-national codes  are  typed  out  as
                         <xy>  (where  xy  is  the corresponding LK201
                         keyboard compose sequence).

                         If  the  bit  is  set  (meaning   that   TECO
                         understands your terminal to be 8-bit), valid
                         DEC multi-national codes  are  typed  out  as
                         themselves.

                         In either case, unprintable or illegal  codes
                         in the 128 to 255 range are typed out as [ab]
                         (where ab is  the  corresponding  hexadecimal
                         code).    The  scope  watch  feature  (screen
                         buffer display, controlled by the W commands)
                         always uses the <xy> and [ab] notations.

               ET&8192   Accent grave as ESCape surrogate.
                         [TECO-11 only]

                         If this bit is set,  TECO  recognizes  the  `
                         (accent   grave)   character   as  an  ESCAPE
                         surrogate.  That is, an ` character typed  at
                         the  console  will be recognized as a command
                         <DELIM> character, and passed to TECO  as  an
                         ESCape.  (This interpretation applies only to
                         <DELIM>s  typed  at  the   console;    ESCape
                         characters  must  still be used in macros and
                         indirect files.) When an ESCape surrogate  is
                         set,  an  ESCape  received  by  TECO echos as
                         accent grave;  when none is  set,  an  ESCape
                         received  by TECO echos as dollar sign.  This
                         feature  is  provided  for  the  benefit   of
                         certain  newer terminals which lack an ESCape
                         key.  (See also the Introduction, and the  EE
                         flag.)

               ET&32768  If this bit is set and a <CTRL/C>  is  typed,
                         the  bit  is turned off, but execution of the
                         current  command   string   is   allowed   to
                         continue.  This allows a TECO macro to detect
                         typed <CTRL/C>s.
                         In TECO-8, this bit is the 2048's bit  rather
                         than the 32768's bit.

               The initial setting of ET is operating system dependent
               (See appendices).  In addition, some of the ET bits are

     Standard TECO                                            PAGE 112
     Mode Control Flags


               automatically turned off by certain error conditions.

     EU        The upper/lower case flag.

               If n is -1, no case flagging of any type  is  performed
               on  type out, lower case characters are output as lower
               case characters.  If n is 0, lower case characters  are
               flagged by outputting a ' (quote) before the lower case
               character and the lower case  character  is  output  in
               upper case;  upper case characters are unchanged.  If n
               is +1, upper case characters are flagged by  outputting
               a  '  (quote)  before  each one and then the upper case
               character is output;  lower case characters are  output
               as their upper case equivalents.

               The initial value of the EU flag is -1 if TECO can tell
               from  the  operating  system  that  the user's terminal
               supports display of lower case  characters;   otherwise
               te initial value is 0.  Consult the appendices for more
               details.

     EV        The edit verify flag is decoded just like the ES  flag.
               Just before TECO prints its prompting *, the EV flag is
               checked.  If it is non-zero the lines to be viewed  are
               printed on the terminal.

               The initial value of the EV flag is 0.
               [TECO-11 only]

     ^X        The search mode flag.
               [Not in TECO-8]

               If ^X is 0, the text argument in a search command  will
               match  text  in  the text buffer independent of case in
               either the search argument or  the  text  buffer.   The
               lower   case   alphabetics   match   the   upper   case
               alphabetics, and "`", "{", "|",  "}",  "~"  match  "@",
               "[",  "\",  "]",  "^"  respectively.   In addition, DEC
               multinational characters having diacritical  marks  are
               regarded   as  matching  the  corresponding  characters
               without diacritical marks.

               If ^X is -1, the search will succeed only if  the  text
               argument  is  identical  to  text  in  the text buffer.
               (This means that lower case does NOT match upper  case,
               nor  does  a  character having a diacritical mark match
               one without).

               The initial value of the ^X flag is 0.  (For control of
               caret  or  uparrow treatment in search strings, see the
               ED&1 bit above.)

     Standard TECO                                            PAGE 113
     Scope Commands


     5.17 SCOPE COMMANDS

     The W command (scope "WATCH") is present in most  implementations
     of  TECO.   There  are two different variations of the W command.
     Neither, one, or both may be present.  ET  flag  Bits  9  and  10
     indicate which variation(s) are configured and can be used.


     5.17.1 Video Terminal Scope Commands

     If the VT support  is  present  and  your  terminal  is  a  video
     terminal  (such  as a VT05, VT52, or VT100), ET flag Bit 9 (value
     512) will be on.


                TABLE 5-17A: VIDEO TERMINAL WATCH COMMANDS

     COMMAND        FUNCTION

     -1W       Refresh the terminal's screen to show the  contents  of
               the text buffer.

     -nW       Tell the video terminal screen refresher that  the  top
               n-1  lines of the screen have been altered.  The screen
               refresher will completely redraw the top n-1  lines  of
               the screen upon the next -1W command.

     nW        Place the default cursor line at line n of the  screen.
               The  initial  default  cursor  line  is  line 16.  This
               command makes the  window  support  forget  the  screen
               image  and  any special associated modes (SEEALL, MARK,
               HOLD).

     0W        Equivalent to "16W".

     W         Forget screen image and special scope modes.

     -1000W    Forget that output was done.   Normally,  if  the  user
               outputs  to the terminal with a command such as T, n^T,
               or  ^A,  TECO  will  believe  that  the  window   needs
               updating,  and  upon  the  next  -1W command, TECO will
               refresh the entire window display.  Issuing the  -1000W
               command  informs  TECO  that the output command did not
               destroy the window.
               [TECO-11 only]

     Standard TECO                                            PAGE 114
     Video Terminal Scope Commands


     The :W commands are used to interrogate and set (see m,n:W below)
     video  terminal  status information, as well as implement some of
     the  more  advanced  features  of  the  video  terminal   "WATCH"
     functions.


                TABLE 5-17B: VIDEO TERMINAL STATUS COMMANDS

     COMMAND        FUNCTION

     0:W       Return a number representing the type of scope  in  use
               as the editing terminal.  Current values are:

               0         VT52
               1         VT61 [TECO-10 only]
               2         VT100 in VT52 mode
               4         VT100 in ANSI mode
               6         VT05
               8         VT102 in ANSI mode
               10        VK100 (GIGI)

     :W        Equivalent to 0:W

     1:W       Return or set the horizontal size of the user's editing
               scope.   This number represents the number of character
               positions available horizontally along the face of  the
               scope.

               If  this  value  is  changed  (see  m,n:W  below),  the
               operating  system  is  automatically  informed  of  the
               terminal's  new  width  setting,  and  the  appropriate
               control  sequence  is  issued  to physically change the
               terminal's screen mode (80 versus 132 column  mode)  if
               needed.

     2:W       Return or set the vertical size of the  user's  editing
               scope.   This  number represents the number of lines of
               text that can appear on the  screen  of  the  terminal.
               This  number  is  affected  by use of the m,7:W command
               (set scrolling region).

     3:W       Return or set SEEALL mode.  0  represents  off  and  -1
               represents on.  In SEEALL mode, a visible indication is
               shown in the  window  for  every  character,  including
               characters that normally don't print.

     4:W       Return or set "mark" status of window support.  0 means
               that  no  mark has been set.  A value of n means that a
               mark has been set at buffer ("dot") position n-1.  This
               status is used by software that uses the window support
               and by the support itself in the case  of  scopes  that
               support reverse video.

     Standard TECO                                            PAGE 115
     Video Terminal Scope Commands


     5:W       Return or set the hold mode indicator.  0 means off, -1
               means hold whole screen, and a positive value, n, means
               hold all but top and bottom n lines.  If hold  mode  is
               on,  then  scrolling  is  inhibited until the cursor is
               about to run off either end of the screen.  This  makes
               the  window  display  more  palatable on terminals on a
               slow line.  If hold mode is on, the window support will
               scroll  the  window  as necessary in an attempt to keep
               the cursor centered.

     6:W       Returns buffer pointer position of character  that  was
               in  the  upper left hand corner of the window as of the
               last -1W command.

     7:W       Return or set the number  of  lines  in  the  scrolling
               (command  dialogue)  portion  of  the  screen.  If n is
               zero, then split screen scrolling  is  disabled.   When
               split   screen   scrolling  is  enabled,  n  lines  (as
               specified) are reserved at the bottom of the screen  to
               scroll  the terminal interaction.  The remainder of the
               screen is used  as  a  display  window  into  the  text
               buffer,   and   is   automatically   updated   by  TECO
               immediately before each command prompt.   This  feature
               functions  only  on  terminals  capable of split screen
               scrolling, such as  members  of  the  VT100  and  VT200
               families.

               The value of n must be greater than 1, and scope height
               minus n must be greater than 9.

               Whenever the scrolling region's size is modified  (that
               is, whenever an m,7:W command is executed), TECO alters
               the scope's height (2:W) accordingly.  For example,  if
               2:W  is currently returning a value of 24, then after a
               5,7:W command 2:W will return a value of 19.  Executing
               a 0,7:W will restore 2:W to 24.

     m,n:W     Sets the entity represented by n:W to m and  returns  a
               value.   If  the  new  setting  has  been accepted, the
               returned value is m.  Elsewise, the returned  value  is
               either  the  old  value associated with n:W or whatever
               new setting  was  actually  set.   In  all  cases,  the
               returned   value  reflects  the  new  current  setting.
               Specific operating systems may put restrictions on  the
               valid values for m.

               Note that each m,n:W command returns a value,  even  if
               your only intent is to set something.  Good programming
               practice suggests following any command which returns a
               value with <DELIM> or ^[ if you don't intend that value
               to be passed to the following command.

     Standard TECO                                            PAGE 116
     Video Terminal Scope Commands


     5.17.2 Refresh Scope Commands

     If refresh scope support  is  present  and  a  refresh  scope  is
     available  (such  as  a VS60 or a VR12), bit value 1024 of the ET
     flag will be on.


                 TABLE 5-17C: REFRESH SCOPE WATCH COMMANDS

     COMMAND        FUNCTION

     W         Update the refresh scope screen to reflect the contents
               of   the  text  buffer  surrounding  the  text  pointer
               ("dot").

     0W        Turn off the refresh scope display.

     nW        Set the number of lines to be displayed around the text
               pointer to n.

     Standard TECO                                            PAGE 117
     Programming Aids


     5.18 PROGRAMMING AIDS

     In addition to the command string editing capabilities  described
     in  Chapter  4,  TECO  includes  various  features  to facilitate
     programming.  These are described in the following sections.


     5.18.1 Text Formatting

     The characters carriage return, line feed, and space are  ignored
     in  command  strings,  except  when they appear as part of a text
     argument.  Numeric values are not affected.  (Inserting  a  space
     between  digits  within  a  digit  string may cause unpredictable
     results).  These characters may be inserted between any two  TECO
     commands  to lend clarity to a long command string.  The carriage
     return/line feed combination is particularly  useful  for  typing
     command strings which are too long to fit on a single line.

     If the character form feed is encountered in a command string and
     it  is  not part of a text argument, a form feed is output to the
     terminal.  This can  be  used  to  format  terminal  output.   On
     TECO-10, execution of the form feed command will clear the screen
     if TECO is in scope command string editing mode (2&ET on).


     5.18.2 Comments

     One of the most powerful features of TECO is its ability to store
     very  long  command  strings so that a given sequence of commands
     may be executed whenever needed.  Long  command  strings  may  be
     thought  of  as  editing  programs  and,  like  any other type of
     program, they should be documented by means of comments.

     Comments may be inserted between any two commands by using a  tag
     construction of the form:

                            !THIS IS A COMMENT!

     Comments may contain any number of characters and any  characters
     except the special characters.  Thus a long TECO macro might look
     like:

                TECO commands !This comment describes line 1!
                TECO commands !This comment describes line 2!
                more commands
                more commands !end of comment string!

     Do not use <TAB> characters to format long command strings!  Only
     <space>,  <CR>,  and  <LF>  can be used to format command strings
     since <TAB> is an insertion command.

     Good TECO code  is  well  structured  and  adequately  commented.
     Unfortunately,  massive  comments  in  a  TECO macro tend to slow

     Standard TECO                                            PAGE 118
     Programming Aids


     execution, especially if they appear within text scanned by GOTOs
     or  unsatisfied  conditionals.  Unless speed is not a goal, it is
     common practice in larger TECO programs  to  strip  out  comments
     before  loading  up  TECO  macros.   Thus the TECO program can be
     adequately commented, yet still run efficiently.

     A large TECO program can start by placing a comment stripper in a
     Q-register,  say  Q-register  C.   Then  it  can successively put
     subroutines (macro text) into the text buffer, do an MC, and load
     the  appropriate Q-register with the resulting text buffer, until
     all the subroutines have been loaded.  Finally, Q-register C  can
     be zeroed and the program started.

     In order for you to strip the comments without  losing  essential
     tags,  you must make a convention for the format of your comments
     so that your comment stripper can  distinguish  them  from  tags.
     There are two common conventions.  In one, the first character in
     every comment after the initial !  is some distinctive character,
     such  as  *.  In the other, all tags start in the left margin and
     all comments are embedded within the  text.   Any  large  comment
     that wants to be on a line by itself starts with a <space> before
     the !.  Both methods allow for readable  code  and  easy  comment
     stripping.


     5.18.3 Messages

     The <CTRL/A> command may be used to print out a statement at  any
     point  during  the  execution  of a command string.  The <CTRL/A>
     command has the general form:

                              ^Atext<CTRL/A>

                                    or

                                 @^A/text/

     The first ^A is the actual  command,  which  may  be  entered  by
     striking  the  control  key  and  the  A key simultaneously or by
     typing a caret (uparrow) followed by an A character.  The  second
     <CTRL/A>  character  of  the  first  form  shown  is  the command
     terminator, which must be entered by typing the control  key  and
     the  A  key  simultaneously.   In  the  second  form,  the second
     occurrence of the delimiting character (shown  as  slash  in  the
     example)  terminates  the  message.  Upon execution, this command
     causes TECO to print the specified message at the terminal.

     The ^Amessage<CTRL/A> command  is  particularly  useful  when  it
     precedes  a  command  whose  numeric  argument  contains ^T or ^F
     characters.  The message may contain instructions  notifying  the
     user as to what sort of input is required.

     Standard TECO                                            PAGE 119
     Programming Aids


     5.18.4 Tracing

     A question mark entered betweeen any two commands  in  a  command
     string  causes  TECO  to  print  all  subsequent  commands at the
     terminal as they are executed.  Commands will be printed as  they
     are executed until another question mark character is encountered
     or the command string terminates.


     5.18.5 Convenience Characters

     In addition to the characters mentioned in Section 5.18.1,  there
     are  several characters which have no special meaning to TECO but
     which may be used to help format your TECO programs  and  command
     strings.   Judicious use of these commands will make your program
     easier to read and maintain.  These characters are  described  in
     the table below:


                    TABLE 5-18A: CONVENIENCE CHARACTERS

     CHARACTER           MEANING

     <NULL>              A  null  (ASCII  0)  encountered  as  a  TECO
                         command  will be ignored.  Numeric values are
                         not affected.  A null read in from  an  input
                         file  will  be discarded (except under RSX-11
                         and  VAX/VMS).   A  null  typed  in  from   a
                         terminal will be ignored.

     <ESCAPE>            An ESCape that is executed as a TECO  command
                         (as distinct from an immediate action command
                         or an ESCape that is part of  the  syntax  of
                         some  other TECO command) is ignored by TECO.
                         However,  any  pending  numeric  values   are
                         discarded.    This   command  is  useful  for
                         discarding the value returned from a  command
                         (such  as  n%q  or m,n:W) when you don't want
                         that  value  to  affect  execution   of   the
                         following command.

     ^[                  Same  as  <ESCAPE>.   Like  any  other   TECO
                         command  that  is a control character, ESCape
                         may be entered in up-arrow  mode.   Sometimes
                         easier  to type, ^[ is also useful on systems
                         whose line-printer spoolers  do  not  visibly
                         print the ESCape character.

                         Any pending  numeric  values  are  discarded.
                         This  command  is  useful  for discarding the
                         value returned from a command (such as n%q or
                         m,n:W)  when  you  don't  want  that value to
                         affect execution of the following command.

     Standard TECO                                            PAGE 120
     Programming Aids


     <ALTMODE>           Some older terminals may have no ESCape  key,
                         but  instead a key labelled ALTMODE or PREFIX
                         which sends  TECO  a  character  whose  ASCII
                         value  is  175  or 176.  In such a case, TECO
                         will treat these characters as if  they  were
                         typed  in  as  an ESCape (octal 33), provided
                         lower to upper case conversion is enabled.

     $ (dollar sign)     Same as <ESCAPE>, but as a command only,  not
                         as a string terminator.
                         [TECO-10 only]

     Note that <TAB> and <FORM FEED> are valid TECO commands and  must
     not be used as aids to formatting TECO programs.


     5.18.6 Memory Expansion

     The nEC command can be used to make TECO reclaim lost space after
     it  had  expanded  memory  usage.   nEC  tells  TECO to expand or
     contract until it uses nK  words  of  memory.   If  this  is  not
     possible,  then  TECO's  memory  usage  does not change.  The 0EC
     command tells TECO to shrink back to its original size  (use  the
     least amount of memory possible).
     [TECO-10 only]

     Standard TECO                                            PAGE 121
     Programming Aids


     5.18.7 Case Control

     The <CTRL/V> and <CTRL/W>  TECO  commands  are  used  to  specify
     automatic  case  control  for  alphabetic  characters  typed into
     strings.


                   TABLE 5-18B: CASE CONTROL CHARACTERS

     CHARACTER      MEANING

     ^V        <CTRL/V> puts TECO into lower case conversion mode.  In
               this   mode,   all   alphabetic  characters  in  string
               arguments are  automatically  changed  to  lower  case.
               This  mode  can  be overridden by explicit case control
               within the  search  string.   This  command  makes  all
               strings behave as if they began with a ^V^V.
               [TECO-10 only]

     ^W        <CTRL/W> puts TECO into upper case conversion mode.  In
               this   mode,   all   alphabetic  characters  in  string
               arguments are  automatically  changed  to  upper  case.
               This  mode  can  be  overriden by explicit case control
               within the  search  string.   This  command  makes  all
               strings behave as if they began with ^W^W.
               [TECO-10 only]

     0^V       Returns TECO to its original  mode.   No  special  case
               conversion  occurs  within  strings  except  those case
               conversions that are explicitly specified by ^V and  ^W
               string build constructs located within the string.
               [TECO-10 only]

     0^W       Same as ^V.
               [TECO-10 only]

     Standard TECO                                            PAGE 122
     Manipulating Large Pages


     5.19 MANIPULATING LARGE PAGES

     TECO is designed to operate most efficiently when  editing  files
     that  contain  no more than several thousand characters per page.
     (TECO storage includes Q-register storage and buffer space.   The
     size  of  the  text  storage  area  is dynamic and depends on the
     amount of available memory.) If any page of an input file is  too
     large  to  fit  in  the  text  area, the TECO input commands will
     terminate reading that page into memory when the first line  feed
     is  encountered  after a point that the buffer is 3/4 full.  (See
     appendices for details.) You can make  room  by  positioning  the
     pointer past a section of text at the beginning of the buffer and
     moving that section out of the buffer with the commands:

               0,.PW0,.K

     It is sometimes advantageous to restrict the amount of  the  file
     that  is  present  in  the  buffer.  For example, each insert and
     delete command must move the entire text that is beyond the point
     of  insertion  or  deletion.   An  operation that does many small
     inserts or deletes may therefore run extremely slowly if the text
     buffer  is large.  Such an operation can be sped up substantially
     by reading the  input  file  with  n:A  commands  and  explicitly
     writing the processed text.

     Standard TECO                                            PAGE 123
     Techniques


     5.20 TECHNIQUES AND EXAMPLES

     The most elementary TECO application, described in Chapter  1  of
     this  manual,  is  creating and editing ASCII files on-line.  The
     user enters short command strings, often consisting of  a  single
     command,  and  proceeds  from  task  to  task  until  the file is
     completely edited.

     Since every editing  job  is  simply  a  long  sequence  of  TECO
     commands,  you may accomplish an entire job with one long command
     string made up of all the short command strings placed end to end
     with  the  intervening double <DELIM> characters removed.  A long
     command string that  performs  a  certain  editing  task  can  be
     considered  a  TECO  "editing  program".  Editing programs may be
     written (using TECO) and stored in the same manner as  any  other
     ASCII  file.  Whenever the program is needed, it may be read into
     the buffer as text, stored in a Q-register, and executed by an Mq
     command.

     For more complex editing jobs, you may want to write and maintain
     a   collection   of   specialized   "editing  subroutines."  TECO
     subroutines can perform such elementary  functions  as  replacing
     every  occurrence  of  two  or  more  consecutive  spaces  with a
     tabulation character, for example, or ensuring that words are not
     hyphenated  across  a  page  boundary.   When  an editing problem
     arises, you can load the right combination  of  subroutines  into
     various  Q-registers,  augment  them  with additional commands if
     necessary, and call them by a "mainline" command string.

     Editing subroutines are essentially macros;  that  is,  sequences
     of  commands  which  perform commonly required editing functions.
     The most powerful application of TECO is the creation and use  of
     a  macro  library.   As  you  perform  an  editing  job, look for
     sequences of operations which might be required in future editing
     assignments.   Load  all of the TECO commands required to perform
     such an operation into a Q-register.  When the job  is  finished,
     write the contents of the Q-register onto an output file (via the
     buffer) and save it in the macro  library.   The  nMq  and  m,nMq
     commands, which were designed to facilitate use of macros, permit
     run-time numeric arguments to be passed to a macro.

     TECO macros can preserve the user's radix, flag values, etc.   By
     using  the Q-register push-down list, the macro can save and then
     restore values and/or text.  For example:

       [0 [1 [2     ! Save contents of Q-registers 0, 1 and 2 !
       +0U0         ! Put any calling argument into Q-register 0 !
       10U1         ! Put a 10 (if radix is decimal) or 8 (if radix is
                      octal) into Q-register 1 !
       ^D           ! Ensure that the current radix is now decimal !
       EUU2         ! Save the case flagging flag !
       -1EU         ! Ensure no case flagging !
       Q0"E 3U0 '   ! Default calling argument to 3 !

     Standard TECO                                            PAGE 124
     Techniques


       ...
       Q2EU         ! Restore the case flagging flag !
       10-Q1"N ^O ' ! Restore radix as octal if needed !
       ]2 ]1 ]0     ! Restore contents of Q-registers 2, 1, and 0 !

     The EI command is particularly useful for executing macros from a
     library,  since  with  it they may be read without disturbing the
     current input file.  This makes it unnecessary to plan in advance
     which  macros  might be needed;  it also saves Q-register storage
     space.  You can retrieve two kinds of TECO command files with  an
     EI  command:   a  file  containing  a TECO command that loads the
     macro into a Q-register for later use, or a file containing  just
     the macro (which must be retrieved with EI each time it is used).

     The following examples are intended to  illustrate  some  of  the
     techniques discussed above.  It would not be practical to include
     examples of the use of every TECO  command,  since  most  of  the
     commands  apply  to  many  diverse  situations.  Instead, you are
     encouraged to experiment with the individual commands on  scratch
     files.


     EXAMPLE 1:  SPLITTING, MERGING, AND REARRANGING FILES

     Assume that there is a file named PROG.DAT on the system disk and
     that this file contains data in the following form:

     AB <FF> CD <FF> EF <FF> GH <FF> IJ <FF> KL <FF> MN <FF> OP

     where each of the letters A, B, C etc., represents  20  lines  of
     text and <FF> represents a form feed character.  The user intends
     to rearrange the file so that it appears in the following format:

     AOB <FF> D <FF> MN <FF> EF <FF> ICJ <FF> KL <FF> P <FF> GH

     The  following   sequence   of   commands   will   achieve   this
     rearrangement.    (Search   command   arguments  are  not  listed
     explicitly.)


                         Start TECO.
     *2ED``              Allow all Y commands.
     *EBPROG.DAT`Y``     Specify input file and get first page.
     *NC``               Search for a character string in C, writing A
                         and B on the output file.
     *J20X1``            Save all of C in Q-register 1.
     *20K``              Delete C from the buffer.
     *NG``               Search for a character string in  G,  writing
                         D, E, and F on the output file.
     *HX2``              Save G and H in Q-register 2.
     *Y``                Delete GH from the buffer and read IJ.
     *20L``              Move the pointer to the beginning of J.
     *G1``               Insert C, which was stored in Q-register 1.

     Standard TECO                                            PAGE 125
     Techniques


     *NM``               Search for a character string in  M,  writing
                         ICJ and KL on the output file.
     *HX1``              Save  MN  in  Q-register  1   (the   previous
                         contents is overwritten).
     *Y``                Delete MN and read OP
     *J20X3``            Save all of O in Q-register 3.
     *20K``              Delete O from the buffer.
     *PWHK``             Write P onto the  output  file,  appending  a
                         form feed, and clear the text buffer.
     *G2``               Bring GH into the buffer from Q-register 2.
     *HPEF``             Write GH on the output file and close it.
     *EBPROG.DAT`Y``     Open the partially revised file.
     *20L``              Move the pointer to the beginning of B.
     *G3``               Insert all of O from Q-register 3.
     *ND``               Search for a character string  in  D  writing
                         AOB on the output file.
     *PWHK``             Write D on the output file and clear buffer.
     *G1``               Bring all of MN from Q-register  1  into  the
                         buffer.
     *EX``               Write MN onto the output file, then close the
                         file and exit.

     At this point the file has been rearranged in the desired format.
     Of  course,  this  rearrangement  could have been accomplished in
     fewer steps if the commands listed above had been  combined  into
     longer  command  strings.   Note  that the asterisks shown at the
     left margin in this example are generated by TECO, and not  typed
     by the user.

     Assume, now, that the same input file,  containing  data  in  the
     form:

     AB <FF> CD <FF> EF <FF> ... <FF> OP

     is to be split into two  separate  files,  with  the  first  file
     containing  AB <FF> CD  and the second file containing KL <FF> M,
     while the rest of the data is to  be  discarded.   The  following
     commands could be used to achieve this rearrangement:


                         Start TECO.
     *2ED``              Allow all Y commands.
     *ERFILE`EWFILE1``   Open the input  file  and  the  first  output
                         file.
     *Y``                Read AB into the buffer.
     *P``                Write AB <FF> onto the output file  and  read
                         CD into the buffer.
     *HPEF``             Write  CD  onto  the  output  file   (without
                         appending  a  form feed), and close the first
                         output file.
     *_K``               Search for a character string  in  K.   After
                         this  command  has  been executed, the buffer
                         will contain KL.  No output is generated.

     Standard TECO                                            PAGE 126
     Techniques


     *EWFILE2`P``        Open the second output file and write KL onto
                         it.  Read MN into the buffer.
     *20L0,.P``          Move the pointer to the end of M, then  write
                         M onto the output file.
     *EF``               Close the output file.
     *HKEX``             Clear the buffer and exit.

     As a final example of file manipulation techniques,  assume  that
     there  are  two  files.   One  file  is  MATH.ONE, which contains
     information in the form:

     AB <FF> CD <FF> EF <FF> GH <FF> IJ <FF> KL

     and the other is MATH.TWO, which contains:

     MN <FF> OP <FF> QR

     If both of these files are stored on DK1, the following  sequence
     of  commands  may  be  used  to merge the two files into a single
     file, MATH.NEW, which contains all of MATH.TWO  followed  by  the
     latter half of file MATH.ONE in the following format:

     MN <FF> OP <FF> QR <FF> GH <FF> IJ <FF> KL


                         Start TECO.
     *2ED``              Allow all Y commands.
     *ERDK1:MATH.TWO``   Open the first input file.
     *EWMATH.NEW``       Open the output file on the default device.
     *Y``                Read MN into the text buffer.
     *NR``               Search for a character string in  R,  writing
                         MN and OP onto the output file.
     *PW``               Write QR onto the output  file,  appending  a
                         form feed.
     *ERDK1:MATH.ONE``   Open the second input file.
     *HKY``              Read AB into the buffer.  QR is over-written.
     *_G``               Search for a character string in G,  deleting
                         AB, CD, and EF, leaving GH in the buffer.
     *NK``               Search for a character string in  K,  writing
                         GH  and  IJ on the output file, leaving KL in
                         the buffer.
     *HPEFHKEX``         Write  KL  onto  the  output  file   (without
                         appending  a  form  feed) and close the file,
                         then exit.

     Standard TECO                                            PAGE 127
     Techniques


     EXAMPLE 2:  ALPHABETIZING BY INTERCHANGE SORT

     Assume that TECO is running and that  the  buffer  contains  many
     short lines of text beginning with an alphabetic character at the
     left margin (i.e., immediately following a line feed).  The lines
     might consist of names in a roster, for example, or entries in an
     index.  The following command string  will  rearrange  the  lines
     into  rough  alphabetical  order,  grouping all lines which begin
     with the character "A" at the beginning of the page, followed  by
     all  lines with "B", and so on.  Note that the algorithm could be
     extended to place the entries in  strict  alphabetical  order  by
     having  it  loop  back  to  perform the same sorting operation on
     successive characters in each line.


     !START! J 0AUA                !Load first character of first line
                                   into Q-register A !
     !CONT!  L 0AUB                !Load first character of next  line
                                   into Q-register B !
     QA-QB"G XA K -L GA 1UZ '      !If A>B, switch the lines and set a
                                   flag (Q-register Z) !
     QBUA                          !Load B into A !
     L Z-."G -L @O/CONT/ '         !Loop back if there is another line
                                   in the buffer !
     QZ"G 0UZ @O/START/ '          !Repeat if a switch was made on the
                                   last pass !


     The same algorithm can be coded  in  a  more  structured  way  as
     follows:


     0UZ                           !clear repeat flag!
     <J 0AUA L                     !Load first character of first line
                                   into Q-register A !
     <0AUB                         !Load first character of next  line
                                   into Q-register B !
     QA-QB"G XA K -L GA -1UZ '     !If A>B, switch the lines and set a
                                   flag !
     QBUA                          !Load B into A !
     L .-Z;>                       !Loop back if there is another line
                                   in the buffer !
     QZ;>                          !Repeat if a switch was made on the
                                   last pass !

     This example is a bit shorter and does not  use  any  GOTOs.   It
     will also run somewhat faster.

     Standard TECO                                            PAGE 128
     Appendix A


                                APPENDIX A


                    Octal & Decimal ASCII Character Set

     (GL characters, on one page)




     Char  Oct Dec   Char Oct Dec   Char Oct Dec   Char Oct Dec


      NUL  000 000    SP  040 032     @  100 064     `  140 096
      ^A   001 001    !   041 033     A  101 065     a  141 097
      ^B   002 002    "   042 034     B  102 066     b  142 098
      ^C   003 003    #   043 035     C  103 067     c  144 099
      ^D   004 004    $   044 036     D  104 068     d  144 100
      ^E   005 005    %   045 037     E  105 069     e  145 101
      ^F   006 006    &   046 038     F  106 070     f  146 102
      ^G   007 007    '   047 039     G  107 071     g  147 103

      BS   010 008    (   050 040     H  110 072     h  150 104
      TAB  011 009    )   051 041     I  111 073     i  151 105
      LF   012 010    *   052 042     J  112 074     j  152 106
      VT   013 011    +   053 043     K  113 075     k  153 107
      FF   014 012    ,   054 044     L  114 076     l  154 108
      CR   015 013    -   055 045     M  115 077     m  155 109
      ^N   016 014    .   056 046     N  116 078     n  156 110
      ^O   017 015    /   057 047     O  117 079     o  157 111

      ^P   020 016    0   060 048     P  120 080     p  160 112
      ^Q   021 017    1   061 049     Q  121 081     q  161 113
      ^R   022 018    2   062 050     R  122 082     r  162 114
      ^S   023 019    3   063 051     S  123 083     s  163 115
      ^T   024 020    4   064 052     T  124 084     t  164 116
      ^U   025 021    5   065 053     U  125 085     u  165 117
      ^V   026 022    6   066 054     V  126 086     v  166 118
      ^W   027 023    7   067 055     W  127 087     w  167 119

      ^X   030 024    8   070 056     X  130 088     x  170 120
      ^Y   031 025    9   071 057     Y  131 089     y  171 121
      ^Z   032 026    :   072 058     Z  132 090     z  172 122
      ESC  033 027    ;   073 059     [  133 091     {  173 123
      FS   034 028    <   074 060     \  134 092     |  174 124
      GS   035 029    =   075 061     ]  135 093     }  175 125
      RS   036 030    >   076 062     ^  136 094     ~  176 126
      US   037 031    ?   077 063     _  137 095     DEL    177 127




     Continued...

     Standard TECO                                            PAGE 129
     Appendix A


                           APPENDIX A, Continued


       Octal, Hexadecimal, & Decimal ASCII Character Set (Complete)




              Hex   Oct   Dec   Char    Description

              [00]  000     0.  <NUL>
              [01]  001     1.  ^A      Control-A
              [02]  002     2.  ^B      Control-B
              [03]  003     3.  ^C      Control-C
              [04]  004     4.  ^D      Control-D
              [05]  005     5.  ^E      Control-E
              [06]  006     6.  ^F      Control-F
              [07]  007     7.  ^G      Bell

              [08]  010     8.  <BS>    Backspace
              [09]  011     9.  <TAB>   Horizontal tab
              [0A]  012    10.  <LF>    Line feed
              [0B]  013    11.  <VT>    Vertical tab
              [0C]  014    12.  <FF>    Form feed
              [0D]  015    13.  <CR>    Carriage return
              [0E]  016    14.  <SO>    Control-N
              [0F]  017    15.  <SI>    Control-O

              [10]  020    16.  ^P      Control-P
              [11]  021    17.  <XON>   Control-Q
              [12]  022    18.  ^R      Control-R
              [13]  023    19.  <XOFF>  Control-S
              [14]  024    20.  ^T      Control-T
              [15]  025    21.  ^U      Control-U
              [16]  026    22.  ^V      Control-V
              [17]  027    23.  ^W      Control-W

              [18]  030    24.  ^X      Control-X
              [19]  031    25.  ^Y      Control-Y
              [1A]  032    26.  ^Z      Control-Z
              [1B]  033    27.  <ESC>   ESCape, control-[
              [1C]  034    28.  <FS>    Control-\
              [1D]  035    29.  <GS>    Control-]
              [1E]  036    30.  <RS>    Control-^
              [1F]  037    31.  <US>    Control-_




     Continued...

     Standard TECO                                            PAGE 130
     Appendix A


                           APPENDIX A, Continued


       Octal, Hexadecimal, & Decimal ASCII Character Set (Complete)




              Hex   Oct   Dec   Char    Description

              [20]  040    32.          Space
              [21]  041    33.  !       Explanation point
              [22]  042    34.  "       Double quotation mark
              [23]  043    35.  #       Number sign
              [24]  044    36.  $       Dollar sign
              [25]  045    37.  %       Percent sign
              [26]  046    38.  &       Ampersand
              [27]  047    39.  '       Single quote,  apostrophe

              [28]  050    40.  (       Left parenthesis
              [29]  051    41.  )       Right parenthesis
              [2A]  052    42.  *       Asterisk
              [2B]  053    43.  +       Plus
              [2C]  054    44.  ,       Comma
              [2D]  055    45.  -       Hyphen, minus
              [2E]  056    46.  .       Period, decimal point
              [2F]  057    47.  /       Slash, slant, solidus

              [30]  060    48.  0       Digit 0
              [31]  061    49.  1       Digit 1
              [32]  062    50.  2       Digit 2
              [33]  063    51.  3       Digit 3
              [34]  064    52.  4       Digit 4
              [35]  065    53.  5       Digit 5
              [36]  066    54.  6       Digit 6
              [37]  067    55.  7       Digit 7

              [38]  070    56.  8       Digit 8
              [39]  071    57.  9       Digit 9
              [3A]  072    58.  :       Colon
              [3B]  073    59.  ;       Semicolon
              [3C]  074    60.  _<      Left angle, less than
              [3D]  075    61.  =       Equals
              [3E]  076    62.  _>      Right angle, greater than
              [3F]  077    63.  ?       Question mark




     Continued...

     Standard TECO                                            PAGE 131
     Appendix A


                           APPENDIX A, Continued


       Octal, Hexadecimal, & Decimal ASCII Character Set (Complete)




              Hex   Oct   Dec   Char    Description

              [40]  100    64.  @       Commercial at
              [41]  101    65.  A       Upper case A
              [42]  102    66.  B       Upper case B
              [43]  103    67.  C       Upper case C
              [44]  104    68.  D       Upper case D
              [45]  105    69.  E       Upper case E
              [46]  106    70.  F       Upper case F
              [47]  107    71.  G       Upper case G

              [48]  110    72.  H       Upper case H
              [49]  111    73.  I       Upper case I
              [4A]  112    74.  J       Upper case J
              [4B]  113    75.  K       Upper case K
              [4C]  114    76.  L       Upper case L
              [4D]  115    77.  M       Upper case M
              [4E]  116    78.  N       Upper case N
              [4F]  117    79.  O       Upper case O

              [50]  120    80.  P       Upper case P
              [51]  121    81.  Q       Upper case Q
              [52]  122    82.  R       Upper case R
              [53]  123    83.  S       Upper case S
              [54]  124    84.  T       Upper case T
              [55]  125    85.  U       Upper case U
              [56]  126    86.  V       Upper case V
              [57]  127    87.  W       Upper case W

              [58]  130    88.  X       Upper case X
              [59]  131    89.  Y       Upper case Y
              [5A]  132    90.  Z       Upper case Z
              [5B]  133    91.  [       Opening bracket
              [5C]  134    92.  \       Backslash, reverse slant
              [5D]  135    93.  ]       Closing bracket
              [5E]  136    94.  ^       Circumflex, caret, uparrow
              [5F]  137    95.  _       Underline, underscore




     Continued...

     Standard TECO                                            PAGE 132
     Appendix A


                           APPENDIX A, Continued


       Octal, Hexadecimal, & Decimal ASCII Character Set (Complete)




              Hex   Oct   Dec   Char    Description

              [60]  140    96.  `       Accent grave
              [61]  141    97.  a       Lower case a
              [62]  142    98.  b       Lower case b
              [63]  143    99.  c       Lower case c
              [64]  144   100.  d       Lower case d
              [65]  145   101.  e       Lower case e
              [66]  146   102.  f       Lower case f
              [67]  147   103.  g       Lower case g

              [68]  150   104.  h       Lower case h
              [69]  151   105.  i       Lower case i
              [6A]  152   106.  j       Lower case j
              [6B]  153   107.  k       Lower case k
              [6C]  154   108.  l       Lower case l
              [6D]  155   109.  m       Lower case m
              [6E]  156   110.  n       Lower case n
              [6F]  157   111.  o       Lower case o

              [70]  160   112.  p       Lower case p
              [71]  161   113.  q       Lower case q
              [72]  162   114.  r       Lower case r
              [73]  163   115.  s       Lower case s
              [74]  164   116.  t       Lower case t
              [75]  165   117.  u       Lower case u
              [76]  166   118.  v       Lower case v
              [77]  167   119.  w       Lower case w

              [78]  170   120.  x       Lower case x
              [79]  171   121.  y       Lower case y
              [7A]  172   122.  z       Lower case z
              [7B]  173   123.  {       Opening brace
              [7C]  174   124.  |       Vertical line
              [7D]  175   125.  }       Closing brace
              [7E]  176   126.  ~       Tilde, overline, high line
              [7F]  177   127.  <DEL>   Delete, rubout




     Continued...

     Standard TECO                                            PAGE 133
     Appendix A


                           APPENDIX A, Continued


       Octal, Hexadecimal, & Decimal ASCII Character Set (Complete)




              Hex   Oct   Dec   Char    Description

              [80]  200   128.
              [81]  201   129.
              [82]  202   130.
              [83]  203   131.
              [84]  204   132.  <IND>
              [85]  205   133.  <NEL>
              [86]  206   134.  <SSA>
              [87]  207   135.  <ESA>

              [88]  210   136.  <HTS>
              [89]  211   137.  <HTJ>
              [8A]  212   138.  <VTS>
              [8B]  213   139.  <PLD>
              [8C]  214   140.  <PLU>
              [8D]  215   141.  <RI>
              [8E]  216   142.  <SS2>
              [8F]  217   143.  <SS3>

              [90]  220   144.  <DCS>
              [91]  221   145.  <PU1>
              [92]  222   146.  <PU2>
              [93]  223   147.  <STS>
              [94]  224   148.  <CCH>
              [95]  225   149.  <MW>
              [96]  226   150.  <SPA>
              [97]  227   151.  <EPA>

              [98]  230   152.
              [99]  231   153.
              [9A]  232   154.
              [9B]  233   155.  <CSI>
              [9C]  234   156.  <ST>
              [9D]  235   157.  <OSC>
              [9E]  236   158.  <PM>
              [9F]  237   159.  <APC>




     Continued...

     Standard TECO                                            PAGE 134
     Appendix A


                           APPENDIX A, Continued


       Octal, Hexadecimal, & Decimal ASCII Character Set (Complete)




              Hex   Oct   Dec   --      Description

              [A0]  240   160.          -
              [A1]  241   161.          Inverted exclamation mark
              [A2]  242   162.          Cent sign
              [A3]  243   163.          Pound sterling sign
              [A4]  244   164.          reserved for future
              [A5]  245   165.          Yen
              [A6]  246   166.          reserved for future
              [A7]  247   167.          Section sign

              [A8]  250   168.          General currency sign
              [A9]  251   169.          Copyright sign
              [AA]  252   170.          Feminine ordinal indicator
              [AB]  253   171.          Angle quotation mark left
              [AC]  254   172.          reserved for future
              [AD]  255   173.          reserved for future
              [AE]  256   174.          reserved for future
              [AF]  257   175.          reserved for future

              [B0]  260   176.          Degree sign
              [B1]  261   177.          Plus/minus sign
              [B2]  262   178.          Superscript 2
              [B3]  263   179.          Superscript 3
              [B4]  264   180.          reserved for future
              [B5]  265   181.          Micro sign, Greek mu
              [B6]  266   182.          Paragraph sign, pilcrow
              [B7]  267   183.          Middle dot

              [B8]  270   184.          reserved for future
              [B9]  271   185.          Superscript 1
              [BA]  272   186.          Masculine ordinal indicator
              [BB]  273   187.          Angle quotation mark right
              [BC]  274   188.          Fraction one quarter
              [BD]  275   189.          Fraction one half
              [BE]  276   190.          reserved for future
              [BF]  277   191.          Inverted question mark




     Continued...

     Standard TECO                                            PAGE 135
     Appendix A


                           APPENDIX A, Continued


       Octal, Hexadecimal, & Decimal ASCII Character Set (Complete)




              Hex   Oct   Dec   --      Description

              [C0]  300   192.          A with accent grave
              [C1]  301   193.          A with accent aigu (acute)
              [C2]  302   194.          A with circumflex
              [C3]  303   195.          A with tilde
              [C4]  304   196.          A with umlaut (diaeresis)
              [C5]  305   197.          A with ring
              [C6]  306   198.          AE ligature
              [C7]  307   199.          C with cedilla

              [C8]  310   200.          E with accent grave
              [C9]  311   201.          E with accent aigu (acute)
              [CA]  312   202.          E with circumflex
              [CB]  313   203.          E with umlaut (diaeresis)
              [CC]  314   204.          I with accent grave
              [CD]  315   205.          I with accent aigu (acute)
              [CE]  316   206.          I with circumflex
              [CF]  317   207.          I with umlaut (diaeresis)

              [D0]  320   208.          reserved for future
              [D1]  321   209.          N with tilde
              [D2]  322   210.          O with accent grave
              [D3]  323   211.          O with accent aigu (acute)
              [D4]  324   212.          O with circumflex
              [D5]  325   213.          O with tilde
              [D6]  326   214.          O with umlaut (diaeresis)
              [D7]  327   215.          OE ligature

              [D8]  330   216.          O (letter) with slash
              [D9]  331   217.          U with accent grave
              [DA]  332   218.          U with accent aigu (acute)
              [DB]  333   219.          U with circumflex
              [DC]  334   220.          U with umlaut (diaeresis)
              [DD]  335   221.          Y with umlaut (diaeresis)
              [DE]  336   222.          reserved for future
              [DD]  337   223.          German sharp s




     Continued...

     Standard TECO                                            PAGE 136
     Appendix A


                           APPENDIX A, Continued


       Octal, Hexadecimal, & Decimal ASCII Character Set (Complete)




              Hex   Oct   Dec   --      Description

              [E0]  340   224.          a with accent grave
              [E1]  341   225.          a with accent aigu (acute)
              [E2]  342   226.          a with circumflex
              [E3]  343   227.          a with tilde
              [E4]  344   228.          a with umlaut (diaeresis)
              [E5]  345   229.          a with ring
              [E6]  346   230.          ae ligature
              [E7]  347   231.          c with cedilla

              [E8]  350   232.          e with accent grave
              [E9]  351   233.          e with accent aigu (acute)
              [EA]  352   234.          e with circumflex
              [EB]  353   235.          e with umlaut (diaeresis)
              [EC]  354   236.          e with umlaut (diaeresis)
              [ED]  355   237.          i with accent aigu (acute)
              [EE]  356   238.          i with circumflex
              [EF]  357   239.          i with umlaut (diaeresis)

              [F0]  360   240.          reserved for future
              [F1]  361   241.          n with tilde
              [F2]  362   242.          o with accent grave
              [F3]  363   243.          o with accent aigu (acute)
              [F4]  364   244.          o with circumflex
              [F5]  365   245.          o with tilde
              [F6]  366   246.          o with umlaut (diaeresis)
              [F7]  367   247.          oe ligature

              [F8]  370   248.          o (letter) with slash
              [F9]  371   249.          u with accent grave
              [FA]  372   250.          u with accent aigu (acute)
              [FB]  373   251.          u with circumflex
              [FC]  374   252.          u with umlaut (diaeresis)
              [FD]  375   253.          y with umlaut (diaeresis)
              [FE]  376   254.          reserved for future
              [FF]  377   255.          -

     Standard TECO                                            PAGE 137
     Appendix B


                                APPENDIX B


                              ERROR MESSAGES

     TECO error messages consist of a three letter message preceded by
     a question mark (?) or preceeded by ?TEC.  A short description of
     the error optionally follows (dependent on the current  value  of
     the  EH  flag).   Typing  ?  (question mark) immediately after an
     error message printout causes the command string to be printed up
     to  and  including  the character which causes the error message.
     Typing *q (asterisk, Q-register name) immediately after an  error
     message printout saves the entire command string in the specified
     Q-register.  This is especially useful  for  recovering  mistyped
     insert  commands.  Both the ?  and *q facilities may be used when
     an error occurs.

     TECO-11 also produces two warning messages.   These  messages  do
     not abort the command and execution continues.


     %Superseding existing file
                   Indicates that the file to be created as the result
                   of  an  EW  command  already exists.  If the output
                   file is closed the old copy of  the  file  will  be
                   deleted.  The EK command may be used to "take back"
                   the EW command.

     %Search fail in iter
                   Indicates that a search command has  failed  inside
                   iteration  brackets.   A  ;   (semi-colon)  command
                   immediately  following  the  search   command   can
                   typically  be used to suppress this message.  After
                   printing the message, the iteration is  terminated,
                   i.e., TECO simulates a 0;  command.





     These  error  messages  are  listed   alphabetically   by   their
     three-letter code.  In general, these three-letter codes have the
     same meaning on  all  implementations,  although  not  all  error
     messages are produced by each implementation.  The one-line error
     message given here is a paraphrasing of the message given,  which
     may differ slightly from system to system.

     Standard TECO                                            PAGE 138
     Appendix B


     ?ARG    Improper Arguments
                   Three arguments are given (a,b,c or H,c).

     ?BNI    > not in iteration
                   There is a close angle bracket not  matched  by  an
                   open  angle  bracket somewhere to its left.  (Note:
                   an iteration in a macro stored in a Q-register must
                   be complete within the Q-register.)

     ?CCL    CCL.SV not found or EG argument too long
                   The EGcommand` command on OS/8 was unable to locate
                   SYS:CCL.SV  or  the specified command has more than
                   46 characters.

     ?CON    Confused use of conditionals
                   Conditionals,    parenthesized    arguments,    and
                   iterations  must  be  properly  nested.   The  user
                   probably used  some  construct  like:   N"E...(...'
                   where  an  iteration  or  parenthesized argument is
                   begun in a conditional but not  terminated  in  the
                   same conditional.

     ?CPQ    Can't pop into Q-register
                   A ] command has been executed and there is  nothing
                   saved on the Q-register push down list.

     ?DEV    Invalid device
                   A  file  specification  string  in  an  E   command
                   contains an unknown device name.

     ?DTB    Delete too big
                   An nD command  has  been  attempted  which  is  not
                   contained within the current page.

     ?ERR    RSTS/E error message    (RSTS/E only)
                   Some RSTS/E monitor call failed.  The error message
                   text explains the error.

     ?FER    File Error
                   The file specified in an ER, EW or EB  command  was
                   not found.

     ?FNF    File not found "filespec"
                   The requested input file could not be located.   If
                   this  occurred within a macro the colon modified ER
                   or EB command may be necessary.

     ?FUL    Output Command would have overflowed output device
                   The page of text currently in the text buffer  will
                   not fit in the open output file.  Until enough free
                   space can be obtained on the output device the file
                   may  have  to be split.  An EF command to close the
                   current output file, followed by a new  EW  command

     Standard TECO                                            PAGE 139
     Appendix B


                   to  a temporary file may be used.  The files should
                   be  concatenated  when   the   space   problem   is
                   alleviated.

     ?ICE    Illegal ^E Command in Search Argument
                   A search argument contains a  ^E  command  that  is
                   either  not  defined or incomplete.  The only valid
                   ^E commands in search  arguments  are:   ^EA,  ^ED,
                   ^EV, ^EW, ^EL, ^ES, ^E<NNN>, and ^E[A,B,C,...].

     ?IEC    Illegal character "x" after E
                   An invalid E command  has  been  executed.   The  E
                   character must be followed by an alphabetic to form
                   a legal E command (i.e., ER or EX).

     ?IFC    Illegal character "x" after F
                   An invalid F command has been executed.

     ?IFN    Illegal character "x" in filename
                   The filespec  as  an  argument  to  one  of  the  E
                   commands  is  unacceptable to the system.  The file
                   specification must be appropriate to the system  in
                   use.

     ?IIA    Illegal insert arg
                   A command of  the  form  "nItext`"  was  attempted.
                   Combining   character   (nI`)   and  text  (Itext`)
                   insertions is illegal.

     ?ILL    Illegal command "x"
                   An attempt has been made to execute an invalid TECO
                   command.

     ?ILN    Illegal number
                   An 8 or 9 has been entered when the radix  of  TECO
                   is set to octal.

     ?INP    Input error
                   The system has reported an error attempting to read
                   the  current  input  file.   The text buffer may be
                   corrupt.  This operation may be retried, but if the
                   error  persists, you may have to return to a backup
                   file.

     ?IPA    Negative or 0 argument to P
                   The  argument  preceding  a  P  or  PW  command  is
                   negative or 0.

     ?IQC    Illegal " character
                   One of the valid " commands did not  follow  the ".
                   Refer   to   Section  5.14  (conditional  execution
                   commands) for the legal set of commands.

     Standard TECO                                            PAGE 140
     Appendix B


     ?IQN    Illegal Q-register name "x"
                   An illegal Q-register name was specified in one  of
                   the Q-register commands.

     ?IRA    Illegal radix argument to ^R
                   The argument to a ^R radix command must be  8,  10,
                   or 16.

     ?ISA    Illegal search arg
                   The argument preceding a search command is 0.  This
                   argument must not be 0.

     ?ISS    Illegal search string
                   One of the search string  special  characters  (^Q,
                   ^V, ^W, etc.) would have modified the search string
                   delimiter (usually ESCAPE).

     ?IUC    Illegal character "x" following ^
                   The character following an ^ must have ASCII  value
                   between  100  and  137 inclusive or between 141 and
                   172 inclusive.

     ?MAP    Missing '
                   Every conditional (opened with the " command)  must
                   be closed with the ' command.

     ?MEM    Memory overflow
                   Insufficient  memory  available  to  complete   the
                   current  command.   Make  sure  the Q-register area
                   does not contain much unnecessary  text.   Breaking
                   up  the  text  area  into  multiple  pages might be
                   useful.  (See section 5.19.)

     ?MLA    Missing Left Angle Bracket
                   There is a right angle bracket that has no matching
                   left  angle bracket.  An iteration must be complete
                   within the macro or command.

     ?MLP    Missing (
                   There is a right parenthesis that is not matched by
                   a corresponding left parenthesis.

     ?MRA    Missing Right Angle Bracket
                   There is a left angle bracket that has no  matching
                   right angle bracket.  An iteration must be complete
                   within the macro or command.

     ?MRP    Missing )
                   There is a right parenthesis that is not matched by
                   a corresponding left parenthesis.

     Standard TECO                                            PAGE 141
     Appendix B


     ?MSC    Missing Start of Conditional
                   A ' command (end of conditional)  was  encountered.
                   Every  '  command  must be matched by a preceding "
                   (start of conditional) command.

     ?NAB    No arg before ^_
                   The  ^_  command  must  be  preceded  by  either  a
                   specific numeric argument or a command that returns
                   a numeric value.

     ?NAC    No arg before ,
                   A command has been executed in which  a  ,  is  not
                   preceded by a numeric argument.

     ?NAE    No arg before =
                   The =, ==, or  ===  command  must  be  preceded  by
                   either  a  specific  numeric  argument or a command
                   that returns a numeric value.

     ?NAP    No arg before )
                   A ) parenthesis has been  encountered  and  is  not
                   properly preceded by a specific numeric argument or
                   a command that returns a numeric value.

     ?NAQ    No arg before "
                   The " commands must be preceded by a single numeric
                   argument  on  which  the  decision  to  execute the
                   following commands or skip to  the  matching  '  is
                   based.

     ?NAS    No arg before ;
                   The ;  command must be preceded by a single numeric
                   argument  on  which  the  decision  to  execute the
                   following commands or skip to  the  matching  >  is
                   based.

     ?NAU    No arg before U
                   The U command must be preceded by either a specific
                   numeric  argument  or  a  command  that  returns  a
                   numeric value.

     ?NCA    Negative argument to ,
                   A comma was preceded by a negative number.

     ?NYA    Numeric argument with Y
                   The Y command must not  be  preceded  by  either  a
                   numeric  argument  or  a  command  that  returns  a
                   numeric value.

     ?NYI    Not yet implemented
                   A command  was  issued  which  tries  to  invoke  a
                   feature  not  available  on  this implementation of
                   TECO.

     Standard TECO                                            PAGE 142
     Appendix B


     ?NFI    No file for input
                   Before issuing an input command, such as Y,  it  is
                   necessary to open an input file by use of a command
                   such as ER or EB.

     ?NFO    No file for output
                   Before issuing an output command such as  N  search
                   or  P it is necessary to open an output file by use
                   of a command such as EW or EB.

     ?NPA    Negative or 0 argument to P
                   A P  command  was  preceded  by  a  negative  or  0
                   argument.

     ?NRO    No room for output
                   The  output  device  is  too  full  to  accept  the
                   requested output file.

     ?NYI    Not Yet Implemented
                   A command was issued that is not yet implemented in
                   this version of TECO.

     ?OFO    Output file already open
                   A command has been executed which tried  to  create
                   an  output  file,  but  an output file currently is
                   open.  It is typically appropriate to use the EC or
                   EK  command as the situation calls for to close the
                   output file.

     ?OUT    Output error
                   The system has reported an error attempting  to  do
                   output  to  the output file.  Make sure that output
                   device did not become write locked.  Use of the  EF
                   command  (or EK if necessary) and another EW can be
                   considered until the condition is fixed.

     ?PES    Attempt to Pop Empty Stack
                   A ]  command  (pop  off  q-register  stack  into  a
                   q-register)  was encountered when there was nothing
                   on the q-register stack.

     ?PDO    Push-down list overflow
                   The  command  string  has   become   too   complex.
                   Simplify it.

     ?POP    Attempt to move Pointer Off Page with "x"
                   A J,  C  or  R  command  has  been  executed  which
                   attempted  to  move  the pointer off the page.  The
                   result of executing  one  of  these  commands  must
                   leave  the pointer between 0 and Z, inclusive.  The
                   characters referenced by a D or m,nX  command  must
                   also be within the buffer boundary.

     Standard TECO                                            PAGE 143
     Appendix B


     ?SNI    ; not in iteration
                   A ;  command has been executed outside of  an  open
                   iteration   bracket.   This  command  may  only  be
                   executed within iteration brackets.

     ?SRH    Search failure "text"
                   A search command not preceded by a  colon  modifier
                   and  not within an iteration has failed to find the
                   specified "text".  After  an  S  search  fails  the
                   pointer  is  left  at  the beginning of the buffer.
                   After an N or _ search fails the last page  of  the
                   input  file  has  been input and, in the case of N,
                   output, and the buffer is cleared.  In the case  of
                   an  N  search  it is usually necessary to close the
                   output file and reopen it for continued editing.

     ?STL    String too long
                   A search or file name string is too long.  This  is
                   most  likely  the result of a missing <DELIM> after
                   the string.

     ?TAG    Missing Tag !tag!
                   The tag !tag!  specified by an O command cannot  be
                   found.  This tag must be in the same macro level as
                   the O command referencing it.

     ?UTC    Unterminated command "x"
                   This is a general error which is usually caused  by
                   an   unterminated   insert,   search,  or  filespec
                   argument,   an   unterminated   ^A   message,    an
                   unterminated  tag  or comment (i.e., unterminated !
                   construct), or a missing ' character which closes a
                   conditional execution command.

     ?UTM    Unterminated macro
                   This error is the same as  the  ?UTC  error  except
                   that  the unterminated command was executing from a
                   Q-register (i.e., it  was  a  macro).   (Note:   An
                   entire command sequence stored in a Q-register must
                   be complete within the Q-register.)

     ?XAB    Execution aborted
                   Execution of TECO was aborted.  This is usually due
                   to the typing of <CTRL/C>.

     ?WLO    System Device Write-Locked
                   TECO-8 needs to write on the system device when  it
                   is  running in less than 16K (less than 20K if VT52
                   is present) so that it can later swap in overlays.

     ?YCA    Y command aborted
                   An attempt has been made  to  execute  an  Y  or  _
                   search command with an output file open, that would

     Standard TECO                                            PAGE 144
     Appendix B


                   cause text in the text buffer to be erased  without
                   outputting  it  to the output file.  The ED command
                   (section 5.16) controls this check.

     ?nnn    I/O Error or Directive Error              (RSX-11 only)
                   All errors from the executive and file  system  are
                   reported  in  this format, where nnn is the decimal
                   I/O or directive error  status.   The  accompanying
                   message  is  the  corresponding  message  from  the
                   QIOSYM message file.  A complete list  of  I/O  and
                   directive  errors  appears  in  appendices  to  the
                   various Executive  reference  manuals  and  in  the
                   IAS/RSX-11 I/O Operations Reference Manual.

     Standard TECO                                            PAGE 145
     Appendix C


                                APPENDIX C


           Incompatible, Obsolete, and System-Specific Commands

     This appendix describes commands that are  peculiar  to  specific
     operating  systems.   These  commands  fall into many categories.
     Some are obsolete, and are kept around only as a  convenience  to
     the  user.   Others  are so system specific or so obscure that it
     was felt best not to include them in the main body of the manual.
     Some  are  incompatible  across  operating systems.  Some are new
     commands that have not become firmly established and  may  change
     in  the  future.  In general, use these commands at your own risk
     and with the understanding that in future releases of TECO, these
     commands  may change or go away completely.  Implementors of TECO
     on other operating systems should contact  the  TECO  SIG  before
     implementing any of these features.


     C.1 SPECIFIC FEATURES OF TECO-11


     C.1.1 TECO Commands

     Command        Description

     m,nStext`      Performs the same function as the nS command,  but
                    m  serves  a  bound  limit for the search.  If the
                    search string can  be  found  without  moving  the
                    pointer  more  than  ABS(m)-1  places,  the search
                    succeeds  and  the  pointer  is  repositioned   to
                    immediately   after  the  last  character  of  the
                    string.  Otherwise, the pointer is left unchanged.
                    The  ^Q  operator,  described  below, is useful in
                    conjunction with this command.

                    Note that m,Stext` is identical to  m,1Stext`  and
                    m,-Stext` is identical to m,-1Stext`.

     m,-nStext`     Performs the same function as  the  m,nS  command,
                    but searches in the reverse direction.

     0,nStext`      Performs the same  function  as  the  nS  command,
                    except  that  the  pointer  position  will  remain
                    unchanged on search string failure.   (Essentially
                    an  unbounded  search  with no pointer movement on
                    failure.)

     G*             Get most recent  filespec  string.   The  asterisk
                    represents  TECO's  filespec  string  area,  which
                    contains the fully expanded filespec of the last E
                    command  (see  appendices).   Copy the contents of
                    the filespec string area into the  buffer  at  the

     Standard TECO                                            PAGE 146
     Appendix C


                    current  position  of  the buffer pointer, leaving
                    the pointer positioned after  the  last  character
                    copied.

     :G*            Print the contents of the filespec buffer  on  the
                    terminal.

     G_             Get most recent  search  string.   The  underscore
                    (backarrow)  represents TECO's search string area.
                    Copy the contents of the search string  area  into
                    the  buffer  at the current position of the buffer
                    pointer, leaving the pointer positioned after  the
                    last character copied.

     :G_            Print the contents of the search string buffer  on
                    the terminal.

     n^Q            n^QC is identical to nL.  The n^Q command  returns
                    the   number  of  characters  between  the  buffer
                    pointer and the nth line separator (both  positive
                    and   negative).    This   command  converts  line
                    oriented command argument  values  into  character
                    oriented   argument   values.    Used   after   an
                    expression.

     m,-256+n:W     Inserts characters at "dot"  until...   Characters
                    are read (echo off) from the terminal and inserted
                    at "dot" until and  according  to  the  microcoded
                    bits  in  n.   The  terminating  character  is not
                    inserted.

                      128 => Return immediately if no typed characters
                       64 => Terminate on any character
                       32 => Don't keep screen updated (i.e., no -1W)
                        8 => Treat m as terminating character(s)
                        4 => Convert any alphabetic inserts  to  upper
                             case
                        2 => Terminate on <TAB>
                        1 => Screen is initially O.K.

                    Control characters (octal 0  through  37  and  177
                    except  <TAB>)  are always terminating characters.
                    The returned value has the  terminating  character
                    code  in  low byte (octal 0 through 177 or 377 for
                    returned immediately).  The sign bit is set if one
                    or  more  inserts were done.  The return value may
                    be a character code that normally would have  been
                    inserted,  but could not be for some reason (e.g.,
                    convert   alphabetic   inserts   to   upper   case
                    requested,    but    not    supported    in   this
                    implementation).

                    The m of m,-256+n:W is always  optional.   If  bit

     Standard TECO                                            PAGE 147
     Appendix C


                    value  8  of  n  is  set,  m  contains  up  to two
                    additional termination character codes, one in the
                    low  8  bits  (low byte) and another in the high 8
                    bits (high byte).  If only one  extra  termination
                    character  is  desired, it is placed simply placed
                    in m thus setting the high 8 bits to  zero  (which
                    is already a termination character).  If bit value
                    8 of n is not  set,  passing  the  m  argument  is
                    undefined...


     C.1.2 String Build Constructs

     Construct      Description

     <CTRL/E>Q*     <CTRL/E>Q* indicates that the string stored in the
                    filespec  buffer  is  to  be  used in the position
                    occupied by the ^EQ* in the search string.

     <CTRL/E>Q_     <CTRL/E>Q_ indicates that the string stored in the
                    search string buffer is to be used in the position
                    occupied by the ^EQ_ in the search string.

     Standard TECO                                            PAGE 148
     Appendix C


     C.2 SPECIFIC FEATURES OF RT-11

     [For "RT-11 Operating Characteristics", refer to Appendix D.]


     C.3 SPECIFIC FEATURES OF RSTS/E

     [For "RSTS/E Operating Characteristics", refer to Appendix E.]

                            TECO COMMANDS

     Command        Description

     :EGRTS`        Switch to private default run-time-system.

     :EGRTS foo`    Switch to RTS "foo".

     :EGFSS string` File string scan "string".

     :EGCCL cmd`    Try "cmd" as a CCL command.

     :EGRUN file`   Try to run "file".

     :EGRUN file=xx`
                    Try to run "file" with "xx" placed in core common.

     :EGEMT`        Issue a monitor directive.  The  FIRQB  is  loaded
                    from Q-registers A through P and the XRB is loaded
                    from Q-registers Q through W.  The low byte of the
                    value  in  Q-register A is the monitor EMT code to
                    issue.   If  the  high  byte  of  the   value   in
                    Q-register   A   is  >0  then  the  text  part  of
                    Q-register A is put into the  XRB  for  a  'write'
                    (XRLEN=  size of A, XRBC=size of A, XRLOC->A);  if
                    Q-register A high byte is <0 then the text part of
                    Q-register  A  is  put  into  the XRB for a 'read'
                    (XRLEN=size of A, XRBC=0, XRLOC->A).
                    Returned  value  is  -1   for   success,   0   for
                    unrecognized  command,  or >0 for the RSTS/E error
                    code.  The FIRQB is placed in the numeric part  of
                    Q-regs  A,  B, C, D, E, F, G, H, I, J, K, L, M, N,
                    O, P.  The XRB is placed in the  numeric  part  of
                    Q-regs Q, R, S, T, U, V, W.

     See also section 5.1.2, File Specification Switches.

     Standard TECO                                            PAGE 149
     Appendix C


     C.4 SPECIFIC FEATURES OF RSX-11/M, RSX-11/D, and IAS

     [For "RSX-11 Operating Characteristics", refer to Appendix F.]

     Command        Description

     <CTRL/Z><CTRL/Z><CTRL/Z>
                    Returns   control   to   the   operating    system
                    immediately.        Equivalent      to      typing
                    <CTRL/C><CTRL/C>.

     See also section 5.1.2, File Specification Switches.


     C.5 SPECIFIC FEATURES OF VAX/VMS

     [For "VAX/VMS Operating Characteristics", refer to Appendix G.]

     Command        Description

     <CTRL/Z><CTRL/Z><CTRL/Z>
                    Returns   control    to    VAX/VMS    immediately.
                    Equivalent to typing <CTRL/C><CTRL/C>.

     EG`            Exit with special status
                    TECO's normal exit status code  (as  reflected  by
                    the  DCL  symbols  $STATUS  and  $SEVERITY)  is  1
                    (success).  If the exit was due to an EG` command,
                    the exit status code is 9 (also success).

     :EGSYM symbol_name symbol_value`
                    Defines the DCL local symbol "symbol_name" with  a
                    value   string   of  "symbol_value".   Useful  for
                    creating symbols that will be used  by  a  command
                    procedure upon TECO's exit.

     See also section 5.1.2, File Specification Switches.


     C.6 SPECIFIC FEATURES OF OS/8

     [For "OS/8 Operating Characteristics", refer to Appendix H.]

     Command        Description

     <CTRL/S>       If  used  as  the  first  keystroke  after  TECO's
                    prompt,  this  command is the same as *Z, that is,
                    it saves the last command string in Q-register  Z.
                    This  command echoes as *Z and does not have to be
                    followed by a <DELIM>.

     See also section 5.1.2, File Specification Switches.

     Standard TECO                                            PAGE 150
     Appendix C


     C.7 SPECIFIC FEATURES OF TOPS-10

     [For "TOPS-10 Operating Characteristics", refer to Appendix I.]

     Command        Description

     nEM            Positions a magtape.  You must  open  the  magtape
                    for input with an appropriate ER command before it
                    can be positioned.  Exact positioning  depends  on
                    the  value  of  n,  as  described below.  You must
                    reopen the  magtape  for  output  before  you  can
                    output to it.
                    [TECO-10 only]

                      Value   Action

                      1EM     Rewind  the   currently-selected   input
                              magtape  to load point.  EM is identical
                              to 1EM.

                      3EM     Write an end-of-file record.

                      6EM     Skip ahead one record.

                      7EM     Back up one record.

                      8EM     Skip  ahead  to  logical  end  of   tape
                              (defined  by  two successive end-of-file
                              marks).  Leave  the  magtape  positioned
                              between  the  two  end-of-file  marks so
                              that   successive    output    correctly
                              overwrites the second EOF.

                      9EM     Rewind and unload.

                      11EM    Write 3 inches of blank tape.

                      14EM    Advance tape one file.  This leaves  the
                              tape  positioned  so  that the next item
                              read will be the  first  record  of  the
                              next  file  (or  the  second end-of-file
                              mark at the logical end-of-tape).

                      15EM    Backspace tape one  file.   This  leaves
                              the  tape  positioned  so  that the next
                              item read will be the  end-of-file  mark
                              preceding   the   file  backspaced  over
                              (unless the file is the  first  file  on
                              the tape).

     n^Q            n^QC is identical to nL.  This command returns the
                    number  of  characters  between the buffer pointer
                    and the nth  line  separator  (both  positive  and

     Standard TECO                                            PAGE 151
     Appendix C


                    negative).   This  command  converts line oriented
                    command argument values  into  character  oriented
                    argument values.  Used after an expression.

     F0             Pointer position of start of window.  Same as 6:W.

     FZ             Pointer position of end of window.

     FH             Same as F0,FZ.

     FX             Software  maintained  horizontal   coordinate   of
                    location  of cursor on screen (0-origin).  Updated
                    by  TECO  on  terminal  output.   If  TECO  cannot
                    determine the updated location of the cursor, this
                    value is set to -1.

     nFX            Set value of FX register to n.

     FY             Software   maintained   vertical   coordinate   of
                    location  of cursor on screen (0-origin).  Updated
                    by  TECO  on  terminal  output.   If  TECO  cannot
                    determine the updated location of the cursor, this
                    value is set to -1.

     nFY            Set value of FY register to n.

     FP             Equivalent to FY,FX.

     m,nFP          Equivalent to mFYnFX.

     m,nFF          Updates FY and FX registers as if the m,nT command
                    were executed.

     nFF            Assumes that the scope cursor is pointing  at  the
                    character  that  is  just to the right of the text
                    buffer pointer (the current character).  Then this
                    command  advances  n  screen lines and goes to the
                    end  of  that  line  and  returns   that   pointer
                    position.

     nFQq           Compares  characters   beginning   at   dot   with
                    characters  beginning  at  the  nth  character  in
                    Q-register q (0-origin).  When a  match  fails  or
                    the  match ends, this command moves the pointer to
                    after the last character that matched and  returns
                    the index into the Q-register.

     E=filespec`    Renames the input file.

     E&filespec`    Run the specified program when  TECO  exits.   Can
                    take  a  numeric argument which is the run-offset.
                    0 is the default.

     Standard TECO                                            PAGE 152
     Appendix C


     m,nE*          Does an arbitrary TRMOP to your terminal.
                    [Not available on TOPS-20.]

     ::Gq           Same as :Gq but types literally.

     ::ER           Same as ER but no defaults are used.

     ^Z             Closes output file and exits from TECO.

     ^P             Returns current page number.

     n^P            Executes P commands until page n has been reached.

     n^Y            Executes Y commands until page n has been reached.

     n,m=           Same as m=n^T.

     m,n:^T         Does an arbitrary TTCALL.


See also section 5.1.2, File Specification Switches.

     Standard TECO                                            PAGE 153
     Appendix D


                                APPENDIX D


                      RT-11 OPERATING CHARACERISTICS


     D.1 STARTUP

     TECO is started with the

               .R TECO

     command.  TECO is now immediately ready to accept commands.   The
     text buffer and Q-register areas are empty.

     The EDIT command

               .EDIT/TECO filespec

     is used to edit an already existing file.  It is equivalent to

               .R TECO
               *EBfilespec`Y``

     For those RT-11 users that will use TECO as the primary editor, a
     monitor SET command is provided:

               .SET EDITOR TECO

     Once this command is issued, the /TECO option on the EDIT command
     is  no  longer  necessary  since  the default editor is now TECO.
     Since this SET command only has affect between system bootstraps,
     it  is  recommended that the command be placed in the appropriate
     startup file (e.g., STARTS.COM).

     Now, assuming the SET command has been issued, the command

               .EDIT filespec

     can be used to edit an already existing file.

     The standard RT-11 EDIT command options are  all  available  with
     TECO.

               .EDIT/CREATE filespec
               .EDIT/INSPECT filespec
               .EDIT/OUTPUT:filespec filespec

     Another option, /EXECUTE, is also available:

               .EDIT/EXECUTE[:string] filespec

     The /EXECUTE option causes TECO to process the filespec  (assumed

     Standard TECO                                            PAGE 154
     Appendix D


     .TEC  filetype)  as a set of TECO commands.  If "string" is used,
     the string is  placed  into  TECO's  text  buffer.   If  "string"
     contains  only  alphanumeric  characters,  it does not have to be
     enclosed in quotes.  If it is  to  contain  blanks,  it  must  be
     quoted with single quotes.  The equivalent TECO commands would be

               .R TECO
               *ERfilespec`YHXZHKIstring`MZ``

     Note the input file remains open and can provide  more  input  to
     the macro.


     D.2 FILE SPECIFICATION

     The file access commands  ER,  EB,  EI,  and  EW  accept  a  file
     specification in the standard RT-11 format:

               dev:filename.type

     in which dev:  is a physical  device  name  or  a  user  assigned
     logical  name;   if  dev:   is not specified, the default DK:  is
     assumed.  The filename field must be specified  in  the  commands
     ER, EB, EI, and EW and be a legal RT-11 filename.  The type field
     is a file extension and must be explicitly given if  used  (there
     is  no default).  The EB and EW commands also accept the extended
     notation for an output file size

               dev:filename.type[n]

     The optional [n] specifies the output file size where  n  is  the
     number of blocks to be allocated.


     D.3 BACKUP FILES

     The EB command maintains one level of file backup on RT-11.   The
     pre-edited input file name is changed to

               filename.BAK

     before the new output file is  closed  with  the  original  name.
     Only normal file closing commands (EC, EF, EG, and EX) cause this
     renaming to happen.  If TECO is aborted or  the  output  file  is
     purged  by  the EK command, the input filename remains unchanged.
     Note only one .BAK file for a given name is kept;   earlier  .BAK
     backup files are deleted each time a new backup file is created.

     A good policy to follow when editing is to close the edited  file
     frequently  enough so that an unexpected incident would not cause
     a substantial loss of work.  Files should be backed up regularly.
     TECO  has the power to let an unsuspecting user alter a good file
     into a completely useless state.  The SRCCOM program can be  used

     Standard TECO                                            PAGE 155
     Appendix D


     to verify an editing session.


     D.4 EXIT AND GO

     If TECO is exited via the EGstring` command, the string is passed
     to the system as the next command to execute.  This string may be
     any valid command or an indirect command file specification.


     D.5 REENTER AND CLOSE

     The RT-11 REENTER command may always be used  to  continue  TECO.
     Its primary differences from running TECO is that when REENTER is
     used, the text buffer and Q-register  areas  are  unmodified,  as
     opposed  to when TECO is run the text buffer and Q-register areas
     are cleared.  The input and output  file  are  always  lost  upon
     reentering  TECO.   If  an output file was open before reentering
     TECO, the file will have to be  recreated  with  the  appropriate
     E-command.   (Note that the monitor commands GT ON, GT OFF, LOAD,
     and UNLOAD disallow a REENTER.)

     The output file is not closed if  TECO  is  aborted.   The  RT-11
     CLOSE  command can be used to make the output file permanent, but
     be aware that the output file will not  be  complete  because  of
     internal  buffers that TECO keeps.  TECO may be reentered after a
     CLOSE command.


     D.6 FILE RECOVERY

     TECO can be a useful tool in recovering ASCII  files  lost  on  a
     block  replaceable device.  TECO allows block replaceable devices
     to be opened in a non-file structured mode.  This gives the  user
     the  capability  to open a disk and access ASCII data anywhere on
     it, independent of file boundaries.  The command

               ERdev:`

     is used to open the  device  at  which  point  _  (underscore  or
     backarrow) searches may be used to locate specific ASCII data and
     transfer it to new output files.  Note that  files  tend  to  get
     reproduced,  in whole or part, many places on a block replaceable
     device;  be sure to verify that any given text is indeed complete
     and the correct version.


     D.7 SYSTEM CRASH RECOVERY

     TECO and RT-11 are highly reliable, but if  during  an  important
     edit  session a random system failure should occur, the following
     procedure may help save some or all of the editing.

     Standard TECO                                            PAGE 156
     Appendix D


          1.  Bootstrap the system

          2.  Immediately perform a SAVE command to save  as  much  of
              memory  as  possible  into  a  file on SY:.  The address
              range form of the SAVE command must be used.   The  SAVE
              command  will  not  allow  any part of the monitor to be
              saved, e.g., if you have a 28K system and are running SJ
              you cannot save 28K but only 26.3K.

          3.  Perform standard startup procedures, e.g., DATE.

          4.  Use TECO on the SAVEd file to  try  and  recover  useful
              parts of the edit.


     D.8 VT11 GRAPHICS SUPPORT

     If the monitor supports the VT11 graphics  processor  (GT ON  and
     GT OFF  work)  TECO  will automatically start up in display mode,
     adjusting to both the size of  the  display  screen  and  to  the
     presence or absence of the scroller.

     If the display fails to start  with  a  working  VT11,  TECO  has
     decided  that  there  is  not  enough  free  memory  and will not
     allocate the display file buffer or start the display.

     See Section 5.17 for a description of the available  commands  to
     interact with the display.

     Various aspects of the display screen become immediately  obvious
     upon  seeing  them;  the text pointer, its position and shape and
     its  position  between  lines;   wrap  around  of  more  than  72
     characters  per  line;   the  scroller  interaction  and  so  on.
     Experiment with a scratch file for more familiarity.

     Standard TECO                                            PAGE 157
     Appendix E


                                APPENDIX E


                      RSTS/E OPERATING CHARACERISTICS


     E.1 STARTUP

     RSTS supports all  of  the  standard  TECO  invocation  commands,
     namely

               TECO
               TECO filespec
               TECO filespec=filespec
               MAKE filespec
               MUNG filespec
               MUNG filespec,text

     The CCL command switches /DETACH and /SIZE:n (or /SIZE:+n) can be
     used  with  TECO.  If /DETACH is used and the user's detached-job
     quota has not yet been reached, TECO will detach the  job  before
     any further processing.  If /SIZE:n is used, TECO will pre-expand
     the text and Q-register storage area to nK.  If /SIZE:+n is used,
     TECO  will  set  the  text storage and Q-register storage area to
     n+4K initially (TECO's default startup size is 4K).


     E.2 FILE SPECIFICATION

     The file access commands  ER,  EB,  EW,  and  EI  accept  a  file
     specification in the standard RSTS/E format:

               dev:[p,pn]filename.ext

     in which dev:  is a physical device  name  or  a  logical  device
     name;   if  dev:   is  not  specified,  the  public  structure is
     assumed.  If [p,pn] is not specified, the user's  current  logged
     in  account  is  assumed.   The  filename field must be specified
     whenever the device name references  a  file  structured  device.
     The  .ext  field is a file extension and must be explicitly given
     if used.  There is no default extension except  for  EI  commands
     which default the .ext field to .TEC.

     The file specification switches  /n,  /B+,  /,  and  /B2  may  be
     applied  to  the  ER, EW, and EB commands.  These switches invoke
     special  handling  of  program  lines  containing   <LF>   or   &
     continuation characters.  See Appendix J for more information.

     The file specification switch /B causes TECO to handle  the  file
     as  a  stream  of  8-bit  binary characters;  normal ASCII format
     processing (such as removal of null characters) is not done.

     The   file   specification   switches   /RONLY,   /MODE:n,    and

     Standard TECO                                            PAGE 158
     Appendix E


     /CLUSTERSIZE:n  can  be  included  in a file specification.  TECO
     automatically opens any disk input file in /RONLY mode.  The file
     size  switches /FILESIZE:n and /SIZE:n might leave an output file
     larger than the amount of data output by TECO.  These  file  size
     switches  are  therefore illegal and produce an error if included
     in a file specification.

     The EB and EW commands also accept the extended notation  for  an
     output file protection code

               dev:[p,pn]filename.ext<prot>

     The optional <prot> specifies the output file protection code.


     E.3 BACKUP FILES

     The EB command maintains one level of file backup on RSTS/E.  The
     pre-edited input file name is changed to

               filename.BAK

     before the new output file is  closed  with  the  original  name.
     Only normal file closing commands (EC, EF, EG, and EX) cause this
     renaming to happen.  If TECO is aborted or  the  output  file  is
     purged  by  the EK command, the input filename remains unchanged.
     Note only one .BAK file for a given name is kept;   earlier  .BAK
     backup files are deleted each time a new backup file is created.

     A good policy to follow when editing is to close the edited  file
     frequently  enough so that an unexpected incident would not cause
     a substantial loss of work.  Files should be backed up regularly.
     TECO  has the power to let an unsuspecting user alter a good file
     into a completely useless state.  The FILCOM program can be  used
     to verify an editing session.


     E.4 EXIT AND GO

     If TECO is exited via the  EGstring`  command,  the  "string"  is
     executed  as  a  RSTS/E  CCL  command  after the input and output
     file(s) are closed.


     E.5 ET FLAG HANDLING

     Bit 6 (detach) is handled specially by TECO.  Every time  the  ET
     flag  is  read (used as a numeric value), TECO ensures that Bit 6
     is on if the job is attached or off if the job is detached.  This
     allows  a  TECO macro to check for "detachedness".  If an attempt
     is made to set Bit 6 and the user's detached-job quota  has  been
     reached,  the  request is ignored and Bit 6 will read back as a 0
     (assuming the job is attached).  If Bit 6 is set and  the  user's

     Standard TECO                                            PAGE 159
     Appendix E


     detached-job  quota has not yet been reached, the job will become
     detached.  Further reading of Bit 6 will return a  1,  indicating
     the detached condition.

     Standard TECO                                            PAGE 160
     Appendix F


                                APPENDIX F


                      RSX-11 OPERATING CHARACERISTICS


     F.1 STARTUP

     RSX-11 systems  support  all  of  the  standard  TECO  invocation
     commands, namely

               TECO
               TECO filespec
               TECO filespec=filespec
               MAKE filespec
               MUNG filespec
               MUNG filespec,text

     If any of these commands are not recognized by the system,  check
     with your system manager to see that TECO is properly installed.

     TECO macros may also be invoked with the command

               TECO @filespec

     It is exactly equivalent to

               MUNG filespec

     In systems supporting dynamic task expansion,  TECO  will  expand
     its  buffer space as necessary.  Also, TECO'S buffer space may be
     explicitly allocated in the startup command

               RUN $TEC/INC=n


     F.2 INITIALIZATION

     TECO searches for  the  TECO.INI  startup  file  in  the  current
     default  device  and  directory.  TECO's memory, in which a plain
     TECO command edits the file last edited with a TECO filespec or a
     MAKE   filespec   command,  is  implemented  with  a  file  named
     TECF00.TMP,  also  stored  in  the  current  default  device  and
     directory.

     The initial value of the ED flag is always 1.

     When TECO is initially invoked it will automatically set  the  ET
     and  EU  flags  according to the user's terminal characteristics.
     If the terminal supports CRT style rubouts, then bit 1 of the  ET
     flag  is  set  to  do the same in TECO.  If the terminal supports
     lower case type in, then bit 2 of the ET flag is set and  the  EU
     flag  is set to -1 to turn off case flagging.  If the terminal is

     Standard TECO                                            PAGE 161
     Appendix F


     a CRT type terminal and the version of TECO includes  the  screen
     support  package,  then  bit  9 of the ET flag is set.  While the
     command line is being processed, bit 7 of the ET flag is also set
     to  cause  TECO  to  exit  should any errors occurr.  ET bit 7 is
     cleared every time TECO reaches prompt (*) level.


     F.3 FILE SPECIFICATION

     The file access commands  ER,  EB,  EW,  and  EI  accept  a  file
     specification in the standard RSX-11 format:

               dev:[p,pn]filename.typ;version

     in which dev:  is a physical device  name  or  a  logical  device
     name;   if dev:  is not specified, SY:  is assumed.  If [p,pn] is
     not specified, the user's current default directory  is  assumed.
     The  filename  field  must  be specified whenever the device name
     references a file structured device.  The typ  field  is  a  file
     type  and  must be explicitly given if used.  There is no default
     type except for EI commands which default the .typ field to .TEC.

     The /B2 file specification switch may be applied to the  ER,  EW,
     and  EB  commands  and  invokes special handling of program lines
     containing & continuation characters.  See Appendix  J  for  more
     information.

     The switch /RW may be applied to any file specification in an ER,
     EW,  and  EI  command.   If  the  file specification references a
     magtape, the tape is rewound before the  file  is  opened.   Note
     that  for  output files, this has the effect of zeroing the tape.
     The /RW switch is ignored for all other device types.

     The  presence  of  version  numbers  in  Files-11   causes   file
     processing to behave slightly differently under RSX-11 than under
     other operating systems.  For example, no .BAK  files  are  used;
     each  execution of an EB command simply produces a new version of
     the file.  Thus a user may retain any level of backup he feels to
     be  comfortable.  It also means that one must occasionally delete
     obsolete files to avoid cluttering the disk.  Thus the command

               EBname.typ;version`

     is equivalent to the commands

               ERname.typ;version`EWname.typ;0`

     The EW command also creates a new version (one  higher  than  the
     current  highest)  if no version number is given.  If an explicit
     version number is given, then that number is used, and if another
     file  of  the same name, type, and version previously existed, it
     is superseded without  warning.   (See  use  of  the  EP  and  EK
     commands below.)

     Standard TECO                                            PAGE 162
     Appendix F


     In reading files, version numbers behave the  same  as  in  other
     RSX-11  utilities:   the  default  is  the highest version.  This
     leads to a problem in re-opening the input file while a  file  is
     being  edited  with EB.  Since the output file is already created
     and in the directory, the input file is  no  longer  the  highest
     version.   One may deduce the version number of the input file by
     doing a :G* (typing the file  string  of  the  output  file)  and
     subtracting one from that version number.

     In symmetry with the EB command,  the  EK  command  functions  by
     simply  deleting  the current output file.  Note, however, that a
     supersede (EW of same name, type, and version) is  not  undone  -
     the file is already deleted!

     The EP and EA commands, while simulating two channels  each  with
     an  open file for each of input and output, in fact only keep one
     file open for each to conserve buffer  space.   This  means  that
     they  are only useful for disk files.  Also, it means that if you
     open a file and then supersede it,  you  should  not  switch  the
     input  channel  away  from it with an EP or ER` command, since it
     will not be possible to open the file again.


     F.4 WILD CARD LOOKUP

     The EN command will process wild  card  lookups  on  RSX-11.   To
     preset  the wild card lookup file specification, use the standard
     RSX-11 format

               dev:[p,pn]filename.typ;version

     The device name must reference a file structured disk  device  or
     magtape.  All other fields of the file specification may be fully
     wild (*), including either or both halves of the directory.   The
     version  number  may  be explicit, wild, or default.  As with the
     other file specification commands, there is no default file type.


     F.5 EXITING FROM TECO

     The normal method of exiting from TECO is with  the  EX  command.
     This  copies  the remaining input file to the output file, closes
     all files and exits.

     The <CTRL/C> (or Caret-C) command is the "give up  and  get  out"
     command.  Executed from main command level, it will cause TECO to
     exit regardless of the state of the buffer.  If there is an  open
     output  file,  it  is  deleted.   The <CTRL/C> command is roughly
     equivalent to EKHKEX.

     Standard TECO                                            PAGE 163
     Appendix F


     F.6 <CTRL/C>

     The action taken when the user types  <CTRL/C>  depends  on  what
     TECO is doing.

     If TECO is executing commands, or is awaiting type-in for the  ^T
     command, the ?XAB error occurs.

     If TECO is at command level, typing <CTRL/C> cancels the  command
     string currently being typed and returns TECO to its prompt.  Two
     consecutive <CTRL/C> characters  will  cause  an  instant  HKEKEX
     exit.

     Sometimes it is desireable for a TECO  macro  to  detect  when  a
     <CTRL/C>  was  typed.   By  detecting the <CTRL/C>, the macro can
     exit cleanly  back  to  command  level  (pop  saved  Q-registers,
     restore  any  flag values, etc.).  To do this, the macro sets Bit
     15 (Octal 100000,  Decimal  -32768)  of  the  ET  flag.   When  a
     <CTRL/C>  is  typed, TECO will automatically turn off Bit 15, but
     will continue execution of the  macro.   The  macro  periodically
     checks  Bit  15  and  exits  cleanly  if  it  ever goes off.  For
     example:

              [0 [1 -32768#ETET < ... ET; > 32767&ETET ]1 ]0

     Setting the <CTRL/C> intercept bit in the ET flag  must  be  done
     with  some  care;   if the bit is set inside a command loop which
     does not check it, it will be impossible for the  user  to  abort
     the  loop.   The  only remedy for this situation is to abort TECO
     from another terminal.


     F.7 EXIT AND GO

     If TECO is exited via the  EGstring`  command,  TECO  closes  its
     files  and  exits.   It then causes "string" to be executed as an
     MCR command using the spawn system directive.  This feature works
     only on RSX-11M V3.2 and RSX-11M+ V1 or later.


     F.8 ET FLAG HANDLING

     TECO will automatically turn off the following  bits  in  the  ET
     flag  on  every  error:   Bit 0 (image output), Bit 3 (no echo on
     ^T), Bit 4 (cancel ^O), Bit 5 (no stall on ^T), and  Bit  15  (^C
     trap).

     In addition, TECO always turns off Bit 7 (exit  on  error,  etc.)
     every time is reaches prompt (*) level.

     Bit  6  (the  detach  flag)  controls  TECO'S  treatment  of  the
     terminal.   Normally,  TECO  keeps  the terminal attached to gain
     control of <CTRL/C> interrupts.  Setting bit 6  of  the  ET  flag

     Standard TECO                                            PAGE 164
     Appendix F


     causes  TECO  to  run  with  the terminal detached.  All commands
     function normally, except that typing <CTRL/C> causes the MCR  to
     be  activated,  allowing  other  tasks  to  be  run from the same
     terminal concurrently with TECO.  It is, of  course,  the  user's
     problem  to  sort  out the confusion that will arise if both TECO
     and another task request input from  the  terminal  at  the  same
     time.


     F.9 FILE RECORD FORMAT

     Files-11 files are record structured, while TECO'S text buffer is
     ASCII  stream.   Thus  TECO  must  make  format  conversions when
     reading and writing files.  The conversion depends on the  record
     attributes  of  the  file.  While reading a file, the records are
     packed into the buffer.  If the file is implied carriage  control
     (the  standard RSX-11 source format) or Fortran carriage control,
     TECO inserts a carriage return and line feed after each record to
     make  each  record appear as a line of text in the buffer, unless
     the record ends with ESCAPE, carriage return, line feed, vertical
     tab,  or  form feed.  A record ending in form feed is interpreted
     as an end of page mark;  it stops the read operation and the form
     feed  is  not  entered in the buffer.  If the file has print file
     carriage control, TECO interprets the carriage control bytes  and
     inserts  the  resulting  carriage return and line feed characters
     about the record.  If the input  file  has  no  carriage  control
     (also  called  internal  carriage control), TECO simply packs the
     records together in the text buffer.

     On output, TECO scans the text buffer for carriage  return,  line
     feed,   vertical  tab,  and  form  feed  characters.   Each  such
     character delimits the end of an output record.   If  the  output
     file  is implied or Fortran carriage control, and the record ends
     with exactly carriage return / line feed, the carriage return and
     line  feed are not output with the record;  Otherwise, the record
     is output in its entirety.  The carriage return and line feed are
     also  output  with  the  record  if the record ends with ESCAPE /
     carriage return / line feed.

     Switches may be applied to the input and output files to  control
     their carriage control attributes.  The switch /CR forces implied
     carriage control;  /-CR forces no  (internal)  carriage  control;
     /FT  forces  Fortran  carriage  control.  When a carriage control
     switch is applied to an input file, the file is read as if it had
     that  attribute;   when  the switch is applied to an output file,
     the file is written with that attribute.  Applying a switch to an
     EB  file  specification  causes the switch to apply to both input
     and output files.  When an output file is created,  its  carriage
     control  attributes  are defaulted to those of the currently open
     input file as follows:

     Standard TECO                                            PAGE 165
     Appendix F


          Input               Output

          implied             implied
          none                implied
          FORTRAN             FORTRAN
          print file          implied

     Files read with the  EI  command  have  their  record  attributes
     interpreted in the same manner.  This leads to an unexpected side
     effect with EI files containing  an  entire  command.   The  last
     record of the file presumably contains as its last characters the
     two alt modes which initiate execution of the macro.  If the file
     is  implied  carriage  control, however, there are also the final
     carriage return / line feed belonging to the last  record,  which
     remain  in  the  type in buffer while the macro executes.  If the
     macro attempts to receive input with the  <CTRL/T>  command,  the
     carriage  return  /  line  feed  will be the first two characters
     read.  Alternatively, if the macro does no type in, the  carriage
     return  /  line  feed  will  be  read  by  TECO  as the first two
     characters of the next command.  Then no asterisk (*) will appear
     as the prompt for the next command.  The remedy for both cases is
     for the macro to execute an EI` command early  on.   This  causes
     the  remainder  of  the indirect file to be discarded and further
     input to be read from the terminal.


     F.10 COMMAND LINE PROCESSING

     The mechanism used to process the command line in RSX-11 TECO  is
     designed   to   allow   sophisticated  TECO  users  the  greatest
     flexibility in customizing TECO for their own use.  It  functions
     as follows:

     The initialization routine places the original MCR  command  line
     (if  any)  into  the  filename  buffer.   It copies into the text
     buffer the text of a TECO macro that will be  used  to  interpret
     the command line.  Then it starts up TECO with the command

               HXY HKG* HXZ HK :EITECO``

     in the  type  in  buffer.   This  loads  the  command  line  into
     Q-register  Z  and the macro into Q-register Y.  It then executes
     the file named TECO.TEC located in the user's default  directory,
     if  it exists.  After the user's TECO.TEC, and any files it might
     link to with EI, have been executed, TECO  executes  the  command
     MY``,  thus executing the macro to interpret the command line and
     open the files requested.

     The  TECO.TEC  mechanism  should   not   be   used   for   simple
     initialization;   the  standard  TECO.INI facility should suffice
     for that.  The alternate TECO.TEC facility is  provided  for  the
     sophisticated  user who wants his own command processing and thus
     wishes to usurp control from the normal initialization.

     Standard TECO                                            PAGE 166
     Appendix F


     If an EI`  command  (to  close  the  indirect  command  file)  is
     executed during the processing of a user's TECO.TEC startup file,
     the final MY`` which causes processing of the command line is not
     executed.   This  results  from  the  fact that the MY`` normally
     appears in TECO's type in  after  all  command  files  have  been
     processed.   Executing the EI` command causes all "type ahead" to
     be discarded to allow a TECO command  file  to  prompt  and  read
     input from the terminal (and not read extraneous type ahead).  It
     is assumed that a TECO startup file that executes EI`  and  reads
     input  from  the  terminal will want to manage the rest of TECO's
     startup.  If it still wants to process the command line, it  must
     issue the MY itself.

     Standard TECO                                            PAGE 167
     Appendix G


                                APPENDIX G


                     VAX/VMS OPERATING CHARACERISTICS



     TECO   is   implemented   in   VAX/VMS    as    a    half-native,
     half-compatibility  mode  program.   The  command  processor  and
     editor proper is the same as TECO-11 and  runs  in  compatibility
     mode.   Operating  system interface and file service logic run in
     native mode.


     G.1 STARTUP

     VAX/VMS supports all of the standard  TECO  invocation  commands,
     namely

               TECO
               TECO filespec
               TECO filespec=filespec
               MAKE filespec
               MUNG filespec
               MUNG filespec,text

     If any of these commands are not recognized by  the  system,  see
     the installation instructions (section G.13) in this appendix.

     TECO macros may also be invoked with the command

               TECO @filespec

     It is exactly equivalent to

               MUNG filespec


     G.2 INITIALIZATION

     TECO performs  initialization  by  attempting  to  translate  the
     logical  name  TEC$INIT.   If  this  name  does not translate, no
     special initialization is done.  If it translates to a string  of
     the  form  $filespec  (where "$" is a dollar sign), TECO executes
     the   TECO   commands   in   the   specified   filespec    during
     initialization.  If TEC$INIT translates to any other string, TECO
     executes that string as TECO commands during initialization.  The
     original  command  line  is available in the text buffer when the
     user initialization commands execute.  Generally, you  would  set
     user  private  modes and/or flags at this time.  This is also the
     normal place to detect, strip off, and do  something  appropriate
     with user private qualifiers.

     Standard TECO                                            PAGE 168
     Appendix G


     TECO's memory is controlled by the logical name  TEC$MEMORY.   If
     this name translates to a string of the form $filespec, TECO uses
     the specified file for its  memory.   Otherwise,  TECO  uses  the
     logical name itself as the memory.

     If TECO is requested to load  VTEDIT  at  startup  (e.g.,  via  a
     TECO /VTEDIT  command), it attempts to translate the logical name
     TEC$VTEDIT.  If the name is defined, the  resulting  filespec  is
     used  as  the  file  from  which  to  load  the scope editor.  If
     TEC$VTEDIT is not defined, TECO attempts to translate the logical
     name  TEC$LIBRARY.  If that logical is defined, it is used as the
     (device  and)  directory  name  of  where  to  find   VTEDIT.TEC.
     Elsewise, TECO defaults to SYS$LIBRARY:VTEDIT.TEC.

     These four logical names (TEC$INIT, TEC$MEMORY,  TEC$VTEDIT,  and
     TEC$LIBRARY)  are  the  information  holders corresponding to the
     four standard :EG commands INI, MEM, VTE,  and  LIB  respectively
     (see section 5.1.3).


     G.3 FILE SPECIFICATION

     All file specifiers are subject to  the  VAX/VMS  file  specifier
     rules;   logical  names  and multi-level directories are properly
     handled, including transparent network file access.  The filename
     field  must  be  specified  whenever the device name references a
     file structured device.  The type field must be explicitly  given
     if  used.   There is no default type except for EI commands which
     default the type field to .TEC.

     Qualifiers may be  applied  to  file  specifications  to  control
     format and attributes;  see G.11.

     The qualifier /RW may be applied to any file specification in  an
     ER,  EW,  and EI command.  If the file specification references a
     magtape, the tape is rewound before the  file  is  opened.   Note
     that  for  output files, this has the effect of zeroing the tape.
     The /RW qualifier is ignored for all other device types.

     The  presence  of  version  numbers  in  Files-11   causes   file
     processing  to  behave  slightly  differently  under VAX/VMS than
     under other operating systems.  For example, no  .BAK  files  are
     used;   each  execution  of  an  EB command simply produces a new
     version of the file.  Thus a user may retain any level of  backup
     he  feels  to  be  comfortable.   It  also  means  that  one must
     occasionally delete obsolete files to avoid cluttering the  disk.
     Thus the command

               EBname.typ;version`

     is equivalent to the commands

               ERname.typ;version`EWname.typ;0`

     Standard TECO                                            PAGE 169
     Appendix G


     The EW command also creates a new version (one  higher  than  the
     current  highest)  if no version number is given.  If an explicit
     version number is given, then that number is used, and if another
     file  of  the same name, type, and version previously existed, it
     is superseded without  warning.   (See  use  of  the  EK  command
     below.)

     In reading files, version numbers behave the  same  as  in  other
     VAX/VMS  utilities:   the  default  is the highest version.  This
     leads to a problem in re-opening the input file while a  file  is
     being  edited  with EB.  Since the output file is already created
     and in the directory, the input file is  no  longer  the  highest
     version.   One may deduce the version number of the input file by
     doing a ER`:G*`` which types  the  file  string  of  the  current
     (primary) input file.

     In symmetry with the EB command,  the  EK  command  functions  by
     simply  deleting  the current output file.  Note, however, that a
     supersede (EW of same name, type, and version) is  not  undone  -
     the file is already deleted!

     When  files  are  processed  concurrently  on  the  primary   and
     secondary  channels,  all files are kept open.  Thus the problems
     that occur under RSX-11 do not exist under VAX/VMS.


     G.4 WILD CARD LOOKUP

     Wild card file name processing supports all of the  wild  carding
     facilities  of  RMS.   For  VAX/VMS  V2  and  later  systems this
     includes embedded * and % and multi-level directory wildcarding.


     G.5 SYMBOL CONSTITUENTS

     The match control character ^EC and the  conditional  n"C  accept
     the  VAX/VMS  symbol constituent character set, which consists of
     upper and lower case alphabetics, numerics, ., $, and _.


     G.6 EXITING FROM TECO

     The normal method of exiting from TECO is with  the  EX  command.
     This  copies  the remaining input file to the output file, closes
     all files and exits.

     The <CTRL/C> (or Caret-C) command is the "give up  and  get  out"
     command.  Executed from main command level, it will cause TECO to
     exit regardless of the state of the buffer.  If there is an  open
     output  file,  it  is  deleted.   The <CTRL/C> command is roughly
     equivalent to EKHKEX.

     TECO's normal exit status code (as reflected by the  DCL  symbols

     Standard TECO                                            PAGE 170
     Appendix G


     $STATUS  and `SEVERITY) is 1 (success).  An exit caused by an EG`
     command sets the exit status code to 9 (also success).  An  error
     exit  caused  by  an error or <CTRL/C> with the 128 bit set in ET
     sets the exit  status  code  to  hexidecimal  1000002C  which  is
     SS$_ABORT  with the inhibit message bit set.  All other exits are
     from fatal internal errors and the exit status code is the  fatal
     error status code.


     G.7 <CTRL/C>

     The action taken when the user types  <CTRL/C>  depends  on  what
     TECO is doing.

     If TECO is executing commands, or is awaiting type-in for the  ^T
     command, the ?XAB error occurs.

     If TECO is at command level, typing <CTRL/C> cancels the  command
     string currently being typed and returns TECO to its prompt.  Two
     consecutive <CTRL/C> characters  will  cause  an  instant  HKEKEX
     exit.

     Sometimes it is desireable for a TECO  macro  to  detect  when  a
     <CTRL/C>  was  typed.   By  detecting the <CTRL/C>, the macro can
     exit cleanly  back  to  command  level  (pop  saved  Q-registers,
     restore  any  flag values, etc.).  To do this, the macro sets Bit
     15 (Octal 100000,  Decimal  -32768)  of  the  ET  flag.   When  a
     <CTRL/C>  is  typed, TECO will automatically turn off Bit 15, but
     will continue execution of the  macro.   The  macro  periodically
     checks  Bit  15  and  exits  cleanly  if  it  ever goes off.  For
     example:

              [0 [1 -32768#ETET < ... ET; > 32767&ETET ]1 ]0

     Setting the <CTRL/C> intercept bit in the ET flag  must  be  done
     with  some  care;   if the bit is set inside a command loop which
     does not check it, it will be impossible for the  user  to  abort
     the  loop.   The  only remedy for this situation is to abort TECO
     with <CTRL/Y>, resulting in the loss of the edit.


     G.8 <CTRL/Y>

     <CTRL/Y> is not handled  at  all  by  TECO  and  will  result  in
     trapping  to  the  command  interpreter.  Should you accidentally
     type <CTRL/Y>, immediately type CONTINUE in response to  the  DCL
     prompt to resume editing.


     G.9 EXIT AND GO

     If TECO is exited with  the  EGstring`  command,  the  string  is
     passed  to the command interpreter as the next command to execute

     Standard TECO                                            PAGE 171
     Appendix G


     after TECO has closed its files and exited.  This  feature  works
     only on VAX/VMS V2 and later systems.


     G.10 ET FLAG HANDLING

     TECO will automatically turn off the following  bits  in  the  ET
     flag  on  every  error:   Bit 0 (image output), Bit 3 (no echo on
     ^T), Bit 4 (cancel ^O), Bit 5 (no stall on ^T), and  Bit  15  (^C
     trap).

     In addition, TECO always turns off Bit 7 (exit  on  error,  etc.)
     every time is reaches prompt (*) level.

     Bit 6 (the detach flag) has no meaning in VAX/VMS.


     G.11 FILE RECORD FORMAT

     Files-11 files are record structured, while TECO'S text buffer is
     ASCII  stream.   Thus  TECO  must  make  format  conversions when
     reading and writing files.  The conversion depends on the  record
     attributes  of  the  file.  While reading a file, the records are
     packed into the buffer.  If the file is implied carriage  control
     (the standard VAX/VMS source format) or FORTRAN carriage control,
     TECO inserts a carriage return and line feed after each record to
     make  each  record appear as a line of text in the buffer, unless
     the record ends with ESCAPE, carriage return, line feed, vertical
     tab,   or  form  feed.   A  record  containing  a  form  feed  is
     interpreted as an end of page mark;  it stops the read  operation
     and  the  form feed is not entered in the buffer.  The portion of
     the record after the form feed, if any, is  saved  for  the  next
     input command.  If the file has print file carriage control, TECO
     interprets the carriage control bytes and inserts  the  resulting
     carriage  return  and  line feed characters about the record.  If
     the input file has no  carriage  control  (also  called  internal
     carriage  control), TECO simply packs the records together in the
     text buffer.

     On output, TECO scans the text buffer for carriage  return,  line
     feed,   vertical  tab,  and  form  feed  characters.   Each  such
     character delimits the end of an output record.   If  the  output
     file  is implied or FORTRAN carriage control, and the record ends
     with exactly carriage return / line feed, the carriage return and
     line  feed are not output with the record;  Otherwise, the record
     is output in its entirety.  The carriage return and line feed are
     also  output  with  the  record  if the record ends with ESCAPE /
     carriage return / line feed.

     Qualifiers  may  be  applied  to  the  input  and   output   file
     specifications.   When a carriage control qualifier is applied to
     an input file, the file is read as  if  it  had  that  attribute;
     when  the  qualifier  is  applied  to an output file, the file is

     Standard TECO                                            PAGE 172
     Appendix G


     written with that attribute.  Applying a qualifier to an EB  file
     specification  causes  the  qualifier  to apply to both input and
     output files.

     The following qualifiers may be used to control input processing:

          /-CR                Force "none" file record attributes
          /CR                 Force "Implied" file record attributes
          /FT                 Force "FORTRAN" file record attributes
          /FTN                Same as /FT
          /B2                 BASIC-PLUS-x handling (see Appendix J)

     The  following  qualifiers  may  be  used   to   control   output
     processing:

          /VAR                Create file record format "Var"
          /STM                Create file record format "Stm"
          /-CR                Create file record format "None"
          /CR                 Create file record format "Implied"
          /FT                 Create file record format "FORTRAN"
          /FTN                Same as /FT
          /B2                 BASIC-PLUS-x handling (see Appendix J)

     The   following   qualifiers   may    be    used    to    control
     open/create/access options:

          /RW                 Rewind before open/create
          /SH                 Enable file sharing
          /SHR                Same as /SH

     Below is  a  complete  list  of  valid  TECO  input  file  record
     format/attribute    combinations    and    the   resulting   file
     format/attribute combinations for EB commands:

           Input                     Output
       Format Attribute          Format Attribute

        Fix     none              Var     Implied
        Fix     Implied           Var     Implied
        Fix     FORTRAN           Var     FORTRAN
        Var     none              Var     Implied
        Var     Implied           Var     Implied
        Var     FORTRAN           Var     FORTRAN
        VFC     Print             Var     Implied
        Stm     none              Stm     Implied
        Stm     Implied           Stm     Implied

     Files read with the  EI  command  have  their  record  attributes
     interpreted in the same manner.  This leads to an unexpected side
     effect with EI files containing  an  entire  command.   The  last
     record of the file presumably contains as its last characters the
     two alt modes which initiate execution of the macro.  If the file
     is  implied  carriage  control, however, there are also the final

     Standard TECO                                            PAGE 173
     Appendix G


     carriage return / line feed belonging to the last  record,  which
     remain  in  the  type in buffer while the macro executes.  If the
     macro attempts to receive input with the  <CTRL/T>  command,  the
     carriage  return  /  line  feed  will be the first two characters
     read.  Alternatively, if the macro does no type in, the  carriage
     return  /  line  feed  will  be  read  by  TECO  as the first two
     characters of the next command.  Then no asterisk (*) will appear
     as the prompt for the next command.  The remedy for both cases is
     for the macro to execute an EI` command early  on.   This  causes
     the  remainder  of  the indirect file to be discarded and further
     input to be read from the terminal as soon as the double alt mode
     is encountered.


     G.12 COMMAND LINE PROCESSING

     The mechanism used to process the command line in VAX/VMS TECO is
     designed   to   allow   sophisticated  TECO  users  the  greatest
     flexibility in customizing TECO for their own use.  It  functions
     as follows:

     The initialization routine places  a  built-in  command  decoding
     TECO  macro  into  Q-register  Y  and  the  original command line
     (including the keyword TECO, MAKE, or MUNG) into Q-register Z.

     It then looks for a user private command decoding TECO  macro  by
     attempting

          1.  an EITECO`` if the logical name "TECO" exists, elsewise

          2.  an EISYS$LOGIN:TECO`` if the  logical  name  "SYS$LOGIN"
              exists, elsewise

          3.  an EITECO``

     If the EI succeeds, the found file is executed.  The file may, or
     course,  do  anything  it  pleases.   Generally,  you would use a
     private command decoder to automate some sort of system  specific
     editing  package.   For  example, to implement an editing package
     called FOOBAR, you would define the logical TECO with
               $ DEFINE/SYSTEM TECO dev:[dir]FOOBAR
     define a DCL foreign command symbol with
               $ FOOBAR :== $SYS$SYSTEM:TECO FOOBAR
     and place the TECO macro the  implements  the  FOOBAR  editor  in
     dev:[dir]FOOBAR.TEC.  Now, whenever a TECO, MAKE, MUNG, or FOOBAR
     command is issued, the your macro will gain control.   It  should
     fetch Q-register Z (the original command line), check the command
     type, if it's FOOBAR  then  go  do  its  thing,  else  it  should
     terminate and execute TECO's built-in command decoder.

               GZ               ! Put command into text buffer !
               J ::@S/FOOBAR/"U ! Is the command for us? !
                 @EI//          ! Not for us, turn us off !

     Standard TECO                                            PAGE 174
     Appendix G


                 HK             ! Clear out text buffer !
                 MY             ! Let the real TECO takeover !
               '                ! It's for us, just flow on... !
               $$               ! Double ESCAPE; 1st command's end !
               ...              ! Do your own thing here... !

     This mechanism should not be used for simple initialization;  the
     standard   TEC$INIT  facility  should  suffice  for  that.   This
     facility is provided for the sophisticated user who wants his own
     command processing and thus wishes to usurp control.


     G.13 HELP

     On VAX/VMS, TECO can provide HELP in any of three ways.

     You can issue a HELP command at  TECO's  asterisk  prompt.   This
     HELP  command  obeys  the  standard  VAX/VMS  HELP command syntax
     rules.  The HELP command may be terminated by  either  RETURN  or
     ``.

     You can type the / command  immediately  after  an  error.   (See
     section  4.2.) TECO will respond with a one-paragraph description
     of the error.

     You can set EH to 3.  (See section 5.16.) This will cause TECO to
     automatically  respond  with  a  one-paragraph description of any
     error which occurs.


     G.14 INSTALLING TECO

     TECO is distributed with  VAX/VMS;   the  files  are  already  in
     place.   If  TECO  will receive heavy use, it should be installed
     /OPEN and /HEADER_RESIDENT.

     The following commands, if used in a LOGIN.COM file, would define
     the three normal TECO invocation commands:

               $ TE*CO :== $SYS$SYSTEM:TECO TECO
               $ MAK*E :== $SYS$SYSTEM:TECO MAKE
               $ MU*NG :== $SYS$SYSTEM:TECO MUNG

     The asterisk allows for  abbreviation  of  these  commands.   For
     example, the TE*CO definition permits TE, TEC, or TECO.

     One may include command qualifiers in  the  command  definitions.
     For  example, one can define a command to invoke TECO with VTEDIT
     as follows:

               $ VTECO :== $SYS$SYSTEM:TECO TECO /VTEDIT

     Standard TECO                                            PAGE 175
     Appendix H


                                APPENDIX H


                      OS/8 OPERATING CHARACTERISTICS


     H.1 STARTUP

     TECO is started with the

               .R TECO

     command.  TECO is now immediately ready to accept commands.   The
     text buffer and Q-register areas are empty.

     The TECO command

               .TECO filespec

     is used to edit an already existing file.  It is equivalent to

               .R TECO
               *EBfilespec`Y``

     OS/8 "remembers" the filespec as the name of the last  file  that
     has been edited.

     The MAKE command

               .MAKE filespec

     is used to create a new file.  It is equivalent to

               .R TECO
               *EWfilespec``

     OS/8 "remembers" the filespec as the name of the last  file  that
     was edited.

     The command

               .TECO filespec1=filespec2

     is used to edit filespec2 into filespec1.  That is, filespec2  is
     opened  as the input file, and filespec1 is created as the output
     file.  It is equivalent to

               .R TECO
               *ERfilespec2`EWfilespec1`Y``

     OS/8 "remembers" the filespec1 as the name of the last file  that
     was edited.

     Standard TECO                                            PAGE 176
     Appendix H


     The command

               .TECO

     with no arguments, causes CCL to execute the command

               .TECO filespec

     where filespec was the file that was previously remembered as the
     last  file  to be edited.  The system purposely does not remember
     filenames from one day to the next, but it  will  remember  names
     across bootstraps.

     The command

               .MUNG filespec

     executes the specified TECO program.  The  default  extension  is
     .TEC .  This is equivalent to the sequence:

               .R TECO
               *ERfilespec`YHXYHKMY``

     Another format of this command is

               .MUNG filespec,argument

     which is used to pass an argument to the TECO program to  control
     its action.  This is equivalent to the sequence:

               .R TECO
               *ERfilespec`YHXYHKIargument`MY``


     The argument may be the name of a file that the TECO  program  is
     to  mung,  or  it may be a command to the program to specify what
     action to take, or whatever.  It is up to  the  TECO  program  to
     decode  this argument (which is left in the text buffer) and take
     appropriate action.  A TECO program executed via the MUNG command
     must  never  destroy  the  text  storage area of Q-register Y and
     expect to ever see the light of day again.

     Note the input file remains open and can provide  more  input  to
     the macro.


     H.2 STARTUP CONDITIONS

     The initial value of the EU flag is 0 if the CCL command SET  TTY
     NO SCOPE had been previously issued, and is -1 if the CCL command
     SET TTY SCOPE had previously been issued.

     The initial value of the ET flag is as follows:

     Standard TECO                                            PAGE 177
     Appendix H


          Bit value      Initial value

               1         0
               2         0 (1 if terminal is a scope)
               4         0
               8         0
               16        0
               32        0
               64        0
               128       1 (TECO's prompt sets this to 0)
               256       0
               512       0 (1 if VT support is present)
               1024      0 (1 if VR12 support is present)
               2048      0

     The initial value of the ED flag is 1.


     H.3 FILE SPECIFICATION

     The  file  access  commands  ER,  EB,  and  EW  accept   a   file
     specification in the standard OS/8 format:

               dev:filename.type

     in which dev:  is a physical  device  name  or  a  user  assigned
     logical  name;   if  dev:  is not specified, the default DSK:  is
     assumed.  The filename field must be specified  in  the  commands
     ER, EB, and EW and be a legal OS/8 filename.  The type field is a
     file extension and must be explicitly given if used (there is  no
     default).   Any characters after the second will be ignored, thus
     the filespecs FOO.TEC and FOO.TE are equivalent.  The EB  and  EW
     commands  do  not accept the extended notation for an output file
     size

                            dev:filename.type[n]

     specifying an output size allocation.


     H.5 BACKUP FILES

     The EB command maintains one level of file backup on  OS/8.   The
     pre-edited input file name is changed to

               filename.BK

     before the new output file is  closed  with  the  original  name.
     Only normal file closing commands (EC, EF, EG, and EX) cause this
     renaming to happen.  If TECO is aborted or  the  output  file  is
     purged  by  the EK command, the input filename remains unchanged.
     Note only one .BK file for a given name  is  kept;   earlier  .BK
     backup files are deleted each time a new backup file is created.

     Standard TECO                                            PAGE 178
     Appendix H


     A good policy to follow when editing is to close the edited  file
     frequently  enough so that an unexpected incident would not cause
     a substantial loss of work.  Files should be backed up regularly.
     TECO  has the power to let an unsuspecting user alter a good file
     into a completely useless state.  The SRCCOM program can be  used
     to verify an editing session.


     H.6 EXIT AND GO

     If TECO is exited via the EGstring` command, the string is passed
     to the system as the next command to execute.  This string may be
     any valid command or an indirect command file specification.  The
     command  may  be  either a KBM or a CCL command.  This command is
     especially useful while running under BATCH.

     If TECO is exited via the EG` command, then OS/8 will  re-execute
     the  last  explicit  compile-class command that was executed that
     day.  The  commands  that  are  considered  to  be  compile-class
     commands are:

     COMPILE file
     LOAD file
     EXECUTE file
     LINK file
     MACRO file.

     This feature, combined with OS/8's  other  remembering  features,
     minimizes the number of keystrokes necessary to do normal program
     development.  The programmer does not have to constantly type  in
     the  name  of  the  file he is working with.  A typical debugging
     session would look like this:

                    .MAKE FOO.MAC
                    *!type in assembly language file to be executed!
                    *EX``
                    .EXECUTE FOO
                    (get error messages)
                    .TECO
                    *!fix bugs!
                    *EG``      !re-compile and execute program!
                    (watch program work or repeat process)


     H.7 <CTRL/C>

     The action taken when the user types  <CTRL/C>  depends  on  what
     TECO  is doing.  At command level <CTRL/C> is an immediate action
     command.  If typed as the  very  first  character  in  a  command
     string  (not  necessarily the first keystroke) it aborts TECO and
     returns to the keyboard monitor.  If this was done  accidentally,
     TECO  may  be restarted (at your own risk) by using ODT to branch
     to location 207 in your program's image.  If <CTRL/C> is typed in

     Standard TECO                                            PAGE 179
     Appendix H


     the  middle  of  entering  a  command string, then the ?XAB error
     message is given and TECO reprompts with its asterisk.  Note that
     if  TECO  executes <CTRL/C> as a command from command level, TECO
     is aborted.  If TECO executes a <CTRL/C> command  from  within  a
     macro,  TECO  is also aborted.  If a <CTRL/C> is typed while TECO
     is running, or while TECO is typing on the terminal, or while  an
     error  message  is printing, then the ?XAB error message is given
     and TECO reprompts with its asterisk.  TECO will abort similarly,
     if <CTRL/C> is typed while TECO is waiting for input because of a
     ^T command.  Note that if TECO is performing I/O using non-system
     handlers,  the  non-system handler may intercept the <CTRL/C> and
     abort back to the keyboard monitor.  In  such  a  case,  you  may
     attempt  to  re-enter  TECO.  However, part of your file has been
     lost;  good luck in attempting to issue an EF command.   Manually
     resetting the value of Z might recover your data.

     If TECO is executing commands or doing I/O, a <CTRL/C> will  stop
     the operation and generate the ?XAB error message.

     Sometimes it is desireable for a TECO  macro  to  detect  when  a
     <CTRL/C>  was  typed.   By  detecting the <CTRL/C>, the macro can
     exit cleanly back to command  level  (restore  any  flag  values,
     etc.).   To  do  this,  the macro sets Bit 0 (Octal 4000, Decimal
     2048) of the ET flag.   When  a  <CTRL/C>  is  typed,  TECO  will
     automatically  turn off Bit 0, but will continue execution of the
     macro.  The macro periodically checks Bit 0 and exits cleanly  if
     it  ever  goes  off.  If the <CTRL/C> trap bit is on, then the ^T
     can read a <CTRL/C> typed at the terminal.  It has an ASCII value
     of 3.


     H.8 FILE RECOVERY

     TECO can be a useful tool in recovering ASCII  files  lost  on  a
     block   replaceable   device.   TECO  allows  non-file-structured
     devices to be opened in a non-file structured mode.   This  gives
     the  user  the  capability  to  open a disk and access ASCII data
     anywhere on it, independent of file boundaries.  To do this,  you
     must issue a command of the form

               .SET dev:  NOFILES

     to  the  monitor  to  make   it   think   that   your   disk   is
     non-file-structured.  The command

               ERdev:`

     is used to open the  device  at  which  point  _  (underscore  or
     backarrow) searches may be used to locate specific ASCII data and
     transfer it to new output files.  Note that  files  tend  to  get
     reproduced,  in whole or part, many places on a block replaceable
     device;  be sure to verify that any given text is indeed complete
     and the correct version.

     Standard TECO                                            PAGE 180
     Appendix H


     If the disk's directory has not been clobbered  (or  if  you  are
     willing  to  create  a new one), then it is not necessary to turn
     the disk into a non-file-structured device.   Merely  open  up  a
     file  early  on  the disk for input and read through end-of-files
     until you locate the lost file.  To  read  through  end-of-files,
     you  must  use  the  /S  switch on an ER, EB, or EW command.  For
     example, the command

                               ERFOO.MAC/S`

     will open the file FOO.MA for input and put TECO into "SUPERTECO"
     mode.   In  this  mode, TECO will not treat a <CTRL/Z> found in a
     file as an end-of-file  character.   Instead,  <CTRL/Z>  will  be
     treated like any other character.  It is not a line terminator or
     a page terminator.  This mode continues until an ER,  EW,  or  EB
     command is issued without a /S switch.


     H.9 VR12 GRAPHICS SUPPORT

     If TECO is run on a PDP-12, TECO will automatically start  up  in
     display  mode,  adjusting  to both the size of the display screen
     and to the presence or absence of the scroller.

     On  a  PDP-12,  TECO  only  permits  one-page  input  and  output
     handlers.

     See Section 5.17 for a description of the available  commands  to
     interact with the display.

     Various aspects of the display screen become immediately  obvious
     upon  seeing  them;  the text pointer, its position and shape and
     its  position  between  lines;   wrap  around  of  more  than  72
     characters  per  line, and so on.  Experiment with a scratch file
     for more familiarity.


     H.10 EXCEPTIONS

     TECO-8  does  not  support  the  following  commands  which   are
     described in this manual:

          1.  Secondary streams (EP, EA, ER`, EW`)

          2.  Auxiliary command streams (EI)

          3.  Wildcards (EN)

          4.  Zeroing of directories (EZ)

          5.  Magtape commands (EM)

          6.  View command (nV)

     Standard TECO                                            PAGE 181
     Appendix H


          7.  Bounded searches

          8.  Anchored searches

          9.  Search verification (ES)

          10. Command verification (EV)

          11. Backward searches

          12. Extended string build or match constructs (^Ex)

     The following incompatibilities exist between TECO-8 and Standard
     TECO:

          1.  In octal mode, the digits 8 and 9  are  not  treated  as
              errors when occurring in a numeric string.

          2.  The *q immediate  action  command  is  not  implemented.
              Instead,  the  immediate  action  command * has the same
              effect as *Z  of  the  standard.   (The  immediate  mode
              command ^S is still accepted for compatibility with OS/8
              TECO V5.)



     H.11 CHAINING TO TECO

     A user program may chain to TECO  passing  it  a  command  to  be
     executed.  There are two formats that such a command may take.

     Format 1 (the TECO command  format)  passes  TECO  a  valid  TECO
     command  to be executed.  This TECO command is placed in a buffer
     starting at location 17600, one 7-bit ASCII character  per  word.
     A  negative word represents a pointer to a continuation buffer in
     field 1.  There may be any number of  continuation  buffers,  but
     they  must  all begin above location 4000 in field 1.  Since TECO
     clobbers most of field 1, these buffers must in fact start  above
     location  7400.   TECO will never load into page 7400 of field 1.
     The buffer ends with a fullword 0.

     Format 2 (the CCL command format) passes TECO a CCL command to be
     parsed  and  executed.   Such  a  command usually begins with the
     words TECO, MAKE, or MUNG, but is not  limited  to  these  words.
     Such  a  CCL  command  is placed in a buffer starting at location
     17601, one 7-bit ASCII character per word.  Location  17600  must
     be  a  fullword  0  to specify that this format is being used.  A
     negative  word  in  the  buffer  represents  a   pointer   to   a
     continuation  buffer  in  field 1 as described above.  The buffer
     ends with a fullword 0.  If this format is used, the  passed  CCL
     command  will  be  parsed  and  executed by TECO.TEC as described
     below.  A user may write his own TECO.TEC, thus implementing  his
     own  CCL  commands.  There is no limit to the possiblities, other

     Standard TECO                                            PAGE 182
     Appendix H


     than the user's imagination.


     H.12 USER INITIALIZATION

     If a user has a file called TECO.INI  on  SYS:,  then  when  TECO
     starts  up  (via  a  CCL command, it will execute the contents of
     this file (as a TECO macro).  This file must contain a valid TECO
     program  (which  will execute out of Q-register W).  God help you
     if you have any errors in this program.  This start-up file  must
     not modify itself (Q-register W) and must not modify the contents
     of Q-register V.   It  should  not  indiscriminately  modify  the
     contents  of  Q-register  Z or the text buffer.  TECO.INI will be
     executed before TECO opens any  files.   That  is,  if  TECO  was
     invoked  via a MAKE command, TECO.INI will be executed before the
     EW command (for the MAKE) is executed.  At this point,  the  text
     buffer  will  contain a copy of the CCL command that invoked TECO
     (assuming your monitor has TECO.TEC support).  However, TECO  has
     not  as yet parsed this line.  The user may examine this line for
     himself, and modify it, but you had  better  know  what  you  are
     doing  (and  do  it right!).  TECO.TEC will parse the contents of
     the text buffer at the conclusion of execution of TECO.INI.

     If your monitor does not have TECO.TEC  support,  or  if  a  user
     program  chained to TECO passing it a TECO command (rather than a
     CCL command), then the initial TECO command will be in Q-register
     Z  when  TECO.INI gets control.  That command has not as yet been
     executed.  The initialization file may examine  the  contents  of
     Q-register  Z to determine what TECO command will be executed and
     proceed  accordingly.   It  may  also  modify  the  contents   of
     Q-register Z (but you better know what you are doing).

     In this case, TECO.INI is started up via the sequence

                    @:ER/SYS:TECO.INI/"SYHXWHK
                    @^UZ^@teco command^@
                    MW+0ES.,.XWMZES"N0ESMX'``

     which loads TECO.INI into Q-register W, loads the chain  argument
     consisting  of an appropriate teco command into Q-register Z, and
     temporarily stores the value returned by TECO.INI in  the  search
     verification  flag  (this  feature  may  change  in  a subsequent
     release).   Q-register  W  and  ES   are   cleared   before   the
     post-processing  command  in Q-register X is executed.  Note that
     the chain argument may not contain any embedded nulls.


     H.13 RETURNED VALUES FROM TECO.INI

     TECO.INI may also return a  value.   If  your  monitor  does  not
     support  TECO.TEC, then only two values are permitted.  Returning
     a 0 (or not returning anything) is the normal sequence of events.
     Returning  a  1  means  that  TECO should execute the contents of

     Standard TECO                                            PAGE 183
     Appendix H


     Q-register X (via an MX command) after it  executes  the  initial
     TECO command (in Q-register Z).  TECO.INI may set up Q-register X
     with the appropriate post-processing commands.  A typical use  of
     this  feature would be to have TECO.INI load up Q-register I with
     an editing macro and then put an "MI" command in Q-register X for
     subsequent   execution.   If  your  monitor  does  have  TECO.TEC
     support, then TECO.TEC can support  additional  returned  values.
     It  is recommended that TECO.TEC support the returned values of 0
     and 1 as above, but in addition, it may support additional values
     determined by the user.

     Note that TECO.INI is not invoked if TECO is started with  a  RUN
     or R command.


     H.14 TECO.TEC SUPPORT

     If the version of CCL you  are  using  to  invoke  TECO  supports
     TECO.TEC,  then  it will chain to TECO with a 0 at location 17600
     and will pass TECO the invokig CCL command (beginning at location
     17601).   If  TECO  is invoked in this manner, it will parse this
     CCL command by executing  the  TECO  command  line  parser  macro
     stored  in  SYS:TECO.TEC.  This macro can be modified by the user
     to parse switches or do any special processing that  is  desired.
     TECO.TEC is started up via the command

       @I^@ccl command^@:ER/SYS:TECO.TEC/"F^ACan't find SYS:TECO.TEC
                         ^A^C^CA.,ZXV.,ZKMV.,.XV``

     which puts your CCL command in the text  buffer  and  then  loads
     (the first page of) TECO.TEC into Q-register V.  TECO.TEC is then
     executed with the MV command and then Q-register  V  is  cleared.
     It is the responsibility of TECO.TEC to parse the command line in
     the text buffer and do the appropriate processing  and  clean-up.
     It  is  also  the  responsibility of TECO.TEC to execute a user's
     start-up file (TECO.INI) if one is present.  Note  that  TECO.TEC
     is  not  invoked if TECO is started via a RUN or R command.  Also
     note, that the CCL command may not contain any embedded nulls.


     H.15 OVERLAYS

     The key to writing  fast  TECO  programs  lies  in  understanding
     TECO-8's overlay structure.  If TECO-8 is run in 16K or more (20K
     or more if VT support is present),  then  the  overlays  will  be
     memory-resident rather than disk-resident.  Although this is much
     faster than swapping from the disk, swapping  from  memory  still
     involves  some  overhead,  so  it would be wise to structure your
     TECO program to minimize the number of swaps necessary.

     The overlay structure is designed so that the minimal  number  of
     swaps  will  be  required  unless obscure TECO features are used.
     There are five overlays to TECO:

     Standard TECO                                            PAGE 184
     Appendix H


          1.  The I/O-overlay.  This overlay handles file opening  and
              is initially resident.  Thus no swapping is necessary to
              do an initial ER, EW, or EB.

          2.  The  Q-overlay.   This  overlay  contains  most  of  the
              frequently   used  conditional  commands  and  branching
              commands.  It is intended that this overlay swap in once
              and remain in memory until TECO is exited.

          3.  The X-overlay.  This is the  exit  overlay  and  handles
              commands  needed  only when TECO is exiting, such as EX,
              EF, EC, and EG.  It is intended that this  overlay  will
              swap in only once when you are ready to leave TECO.

          4.  The F-overlay.  This overlay contains the flag  commands
              and  other  little-used  commands.   It is intended that
              this overlay be not used at all, or if it  is  used,  it
              will  be used so infrequently that it will not slow down
              system performance.

          5.  The E-overlay.   This  is  the  error  overlay.   It  is
              swapped  in  only  when an error occurs.  It is intended
              that this overlay never be swapped in.


     To write efficient TECO code, the user must  know  exactly  which
     commands  are  handled  by  which  overlay.   This information is
     summarized below.

     Overlay        Commands

     I-overlay      ERfile`, EWfile`, EBfile`, :ERfile`, :EBfile`

     Q-overlay      Otag`, n"Xthen|else', n;, search;, n<...>, <...>

     X-overlay      EC, EG`, EGcmd`, EF, EK, EX,
                    *q, ?, nEJ, n^_, V, ^B, ^E, ^F, ^L, ^N, ^Uqtext`

     F-overlay      ED, EH, EO, ES, ET, EU, ^D, ^O,
                    \, n\, n=, n==, n:=, n:==, |

     Several things are immediately obvious.  The command  0TT  should
     always  be  preferred  to  the V command.  ELSE clauses should be
     avoided.  (In future releases, we will try to move the processing
     of  the | command into overlay Q.) The commands \ and = should be
     used as infrequently as possible from within long-running macros.
     Xq  is  preferred  to  ^Uq  to  load  up  a  Q-register.  -n-1 is
     preferred to n^_ to  take  a  one's  complement.   Radix  changes
     should  be avoided.  Flags, such as ET and ED, should be set once
     at the beginning of a macro, and then not fiddled with if at  all
     possible.

     Standard TECO                                            PAGE 185
     Appendix H


     H.16 INSTALLATION INSTRUCTIONS

     The source of TECO consists of the following modules:

     TECO.MAC       Main module
     TECINI.MAC     Initialization module
     TECTBL.MAC     Tables
     TECDEF.MAC     Global definitions
     TECO12.MAC     VR12 support
     TECOVT.MAC     VT support
     TECOVI.MAC     I/O-overlay
     TECOVQ.MAC     Q-overlay
     TECOVX.MAC     X-overlay
     TECOVF.MAC     F-overlay
     TECERR.MAC     E-overlay and error processor
     TECSRH.MAC     Search processor
     TECNUM.MAC     Arithmetic processor

     Each of these modules should be assembled  (using  MACREL  V2  or
     later).  This can be accomplished via the command

                              .MAC TEC???.MAC

     if your monitor supports wildcards in compile-class commands.

     The resulting relocatable modules are then linked together (using
     LINK  V2  or later) to produce the executable TECO.SV image which
     should be put on SYS:  (but it may reside  on  any  device).   If
     your  monitor  supports TECO.TEC, then TECO.TEC must be placed on
     SYS:.


     H.17 ARITHMETIC PRECISION

     TECO-8 performs 13-bit arithmetic except that multiplication  and
     division  by  negative  numbers gives unpredictable results.  All
     numbers stored in Q-registers are 13 bits long.   Numbers  stored
     in  flags  (such  as  ET,  EU, etc.) are only 12-bits long.  When
     storing a number into a flag, the high order (sign bit) is  lost.
     When  using  the value of a flag in an arithmetic expression, the
     12-bit value is sign extended first.


     H.18 ALTERNATE STARTING ADDRESS

     The normal starting address of TECO is location 00200.   In  this
     (normal)  mode, TECO will simulate tabs by spaces on type out and
     will simulate vertical tabs and form feeds  by  line  feeds.   If
     your  terminal  has  hardware  tabs  and vertical tabs (such as a
     KSR-35), then TECO can take  advantage  of  these  features.   To
     enable this ability, you should change TECO's starting address to
     be 05200.  This can be done by the monitor commands:

     Standard TECO                                            PAGE 186
     Appendix H


               .GET SYS:TECO
               .SAVE SYS:TECO;5200

     H.19 VT05 SUPPORT

     TECO will  automatically  handle  command  string  scope  editing
     correctly on a VT05.  The VT support (obtained via use of the -1W
     command) will handle VT05's correctly.  The VTEDIT macro does not
     currently support the VT05 keypad.

     Standard TECO                                            PAGE 187
     Appendix I


                                APPENDIX I


                     TOPS-10 OPERATING CHARACTERISTICS


     I.1 STARTUP

     TECO is started with the

               .R TECO

     command.  TECO is now immediately ready to accept commands.   The
     text buffer and Q-register areas are empty.  Initial commands may
     also be specifified by  following  the  monitor  command  with  a
     dollar sign ($) and then some TECO commands.  For example,

     .R TECO $3EH

     starts TECO with the help level flag set to 3.

     The TECO command

               .TECO filespec

     is used to edit an already existing file.  It is equivalent to

               .R TECO
               *EBfilespec`Y``

     TOPS-10 "remembers" the filespec as the name  of  the  last  file
     that has been edited.

     The MAKE command

               .MAKE filespec

     is used to create a new file.  It is equivalent to

               .R TECO
               *EWfilespec``

     TOPS-10 "remembers" the filespec as the name  of  the  last  file
     that was edited.

     The command

               .MAKE filespec1=filespec2

     is used to edit filespec2 into filespec1.  That is, filespec2  is
     opened  as the input file, and filespec1 is created as the output
     file.  It is equivalent to

     Standard TECO                                            PAGE 188
     Appendix I


               .R TECO
               *ERfilespec2`EWfilespec1`Y``

     TOPS-10 "remembers" the filespec1 as the name of  the  last  file
     that was edited.

     The command

               .TECO

     with no arguments, causes CCL to execute the command

               .TECO filespec

     where filespec was the file that was previously remembered as the
     last  file  to be edited.  The system purposely does not remember
     filenames from one editing session to the next, that is, when you
     log  out,  the  system  "forgets"  the  name of the file you were
     editing.

     TECO-10 does not require the use of the MUNG command  to  execute
     TECO macros because runnable TECO programs can be created via use
     of the EE command and these can then be run with the  standard  R
     or RUN command.  This TECO command has the format

               EEfilespec`

     which saves away the  current  image  of  TECO  in  the  filename
     specified.   The  default  extension  is  .EXE.  When the file is
     subsequently run (using the  R  or  RUN  monitor  command),  TECO
     resumes execution with the TECO command immediately following the
     EE command.


     I.2 STARTUP CONDITIONS

     The initial value of the EU flag is 0 if you  are  running  on  a
     terminal  that  does not support lower case, and is -1 if you are
     running on a terminal that does support lower case.

     The initial value of the ET flag is as follows:

          Bit value      Initial value

               1         0
               2         0 (1 if terminal is a scope)
               4         1
               8         0
               16        0
               32        0
               64        0
               128       1 (TECO's prompt sets this to 0)
               256       0

     Standard TECO                                            PAGE 189
     Appendix I


               512       0 (1 if VT support is present)
               1024      0
               2048      0

     The initial value of the ED flag is 1.


     I.3 FILE SPECIFICATION

     The  file  access  commands  ER,  EB,  and  EW  accept   a   file
     specification in the standard TOPS-10 format:

               dev:filename.type[p,pn]

     in which dev:  is a physical  device  name  or  a  user  assigned
     logical  name;   if  dev:  is not specified, the default DSK:  is
     assumed.  The filename field must be specified  in  the  commands
     ER,  EB,  and EW and be a legal TOPS-10 filename.  The type field
     is a file extension and must be explicitly given the first  time.
     Thereafter, if a corresponding command is given with no extension
     specified, the system uses the previously specified extension  as
     the default.  The same defaulting rules hold for the dev:  field.
     The <prot> construct is permitted on any output filespecification
     to allow setting the protection of the file being created.


     I.4 BACKUP FILES

     The EB command maintains one level of  file  backup  on  TOPS-10.
     The pre-edited input file name is changed to

               filename.BAK

     before the new output file is  closed  with  the  original  name.
     Only normal file closing commands (EC, EF, EG, and EX) cause this
     renaming to happen.  If TECO is aborted or  the  output  file  is
     purged  by  the EK command, the input filename remains unchanged.
     Note only one .BAK file for a given name is kept;   earlier  .BAK
     backup files are deleted each time a new backup file is created.

     A good policy to follow when editing is to close the edited  file
     frequently  enough so that an unexpected incident would not cause
     a substantial loss of work.  Files should be backed up regularly.
     TECO  has the power to let an unsuspecting user alter a good file
     into a completely useless state.  The FILCOM program can be  used
     to verify an editing session.


     I.5 EXIT AND GO

     If TECO  is  exited  via  the  EG`  command,  then  TOPS-10  will
     re-execute  the  last  explicit  compile-class  command  that was
     executed during that session.

     Standard TECO                                            PAGE 190
     Appendix I


     I.6 <CTRL/C>

     The action taken when the user types  <CTRL/C>  depends  on  what
     TECO  is doing.  At command level <CTRL/C> is an immediate action
     command.  If typed as the  very  first  character  in  a  command
     string  (not  necessarily the first keystroke) it aborts TECO and
     returns to the monitor.  No Control-C trapping is available under
     TOPS-10.   The  ?XAB error message is not supported.  If <CTRL/C>
     is typed in the middle of entering a command  string,  then  TECO
     returns  control  to  the  monitor.   Note  that if TECO executes
     <CTRL/C> as a command from command level, TECO  is  aborted.   If
     TECO  executes  a  <CTRL/C>  command from within a macro, TECO is
     also aborted.  If two consecutive <CTRL/C>s are typed while  TECO
     is  running, or while TECO is typing on the terminal, or while an
     error message is printing, then control returns to the  operating
     system.  If one <CTRL/C> is typed to TECO while it is waiting for
     input, then control returns to the operating system.


     I.7 EXCEPTIONS

     TECO-10  does  not  support  the  following  commands  which  are
     described in this manual:

          1.  Secondary streams (EP, EA, ER`, EW`)

          2.  Wildcards (EN)

          3.  Immediate aids LF and BS.

     The following incompatibilities exist between TECO-10  and  DEC's
     TOPS-10 TECO V24:

          1.  The nA command under TOPS-10 TECO  V24  always  returned
              the  value  of  the current character, regardless of the
              value of n.  In TECO-10,  0A  gives  the  value  of  the
              current character.



     I.8 USER INITIALIZATION

     If a user has a file called TECO.INI in his area, then when  TECO
     starts  up  (via  a CCL command), it will execute the contents of
     this file (as a TECO macro).  This file must contain a valid TECO
     program.   TECO.INI will be executed before TECO opens any files.
     That is, if TECO was invoked via a MAKE command, TECO.INI will be
     executed before the EW command (for the MAKE) is executed.

     Standard TECO                                            PAGE 191
     Appendix I


     I.9 INSTALLATION INSTRUCTIONS

     To create TECO for TOPS-10 from the sources, issue the  following
     commands:

     .LOAD/MAC/COMPILE TECO10.T10+TECO10.MAC
     .SAVE TECO10
     .LOAD/MAC/COMPILE TECERR.T10+TECO10.MAC
     .SAVE TECERR

     To create TECO for TOPS-20 from the sources, issue the  following
     commands:

     @LOAD/MAC/COMPILE TECO10
     @SAVE TECO20

     This builds a raw TECO.  This version of TECO  does  not  contain
     any window support since the W and :W commands are implemented as
     macros.  To load window support, issue the following commands:

     .RUN TECO10 (or TECO20)
     *EITECO10.TEC``
     *EETECO``

     You now have a runnable TECO image with window support.

     I.10 TMPCOR SUPPORT

     The EQ and  E%  commands  support  the  pseudo-device  TMP:   for
     TMPCOR.   Only  the  first three letters of the file name will be
     used, to try and access a TMPCOR file.  If that  fails,  it  will
     try  nnnNAM.TMP  where  nnn  is  your  job  number and NAM is the
     three-character name.  For example:  for job  23,  EQqTMP:FOOBAR`
     will read TMPCOR file FOO or 023FOO.TMP.

     I.11 Q-REGISTER NAMES

     Any printable character (except open parenthesis) is valid  as  a
     Q-register  name.   A  Q-register  whose  name  is  a  lower case
     alphabetic character is the same as  the  Q-register  whose  name
     consists  of the corresponding upper case letter.  Thus Qa and QA
     are equivalent commands.  Q-register names may also be  up  to  6
     characters  long,  by  enclosing  the  name  in  parentheses, for
     example, Q(FOOBAR).  Q-register names may contain  any  printable
     characters,  however  all  characters other than letters, digits,
     dollar-sign, space, and underline are reserved for special use by
     TECO.   A  Q-register  name  consisting  entirely of zero or more
     spaces is the  same  as  Q-register  (),  which  is  special  and
     discussed   below.   Trailing  spaces  in  Q-register  names  are
     discarded, and lower case is converted to upper case.

     Standard TECO                                            PAGE 192
     Appendix I


     I.12 REFERENCING THE TEXT BUFFER AS A Q-REGISTER

     The Q-register with the null name:  () is the text  buffer.   The
     numeric  part  of  this  Q-register  is  the  value  of dot.  The
     sequence [A ]() causes  Q-register  A  to  share  with  the  text
     buffer.   The  old  main  text  buffer is lost (unless it is also
     sharing with some Q-register or if  it  has  been  saved  on  the
     Q-register push-down list).  The text in Q-register A becomes the
     text buffer and the numeric part of Q-register A is used for  "."
     if it is in range, otherwise dot is set to 0.

     I.13 SHARING OF Q-REGISTER POINTERS

     Q-registers may share their text with each  other  and  with  the
     text  buffer  as a result of [ and ] commands.  When a Q-register
     is pushed onto the Q-register pushdown list, all that  is  pushed
     is  the  numeric part of the Q-register and a pointer to the text
     part of the Q-register.  Thus a command such as [A ]B would cause
     Q-registers  A and B to share the same text.  The commands X, ^U,
     and EQ could be applied to either  Q-register  without  modifying
     the other, since the Q-register is unbound from its previous text
     first.  However, the colon-modified forms of X and ^U  append  to
     the  existing  text,  so  a  :X or :^U command for either of them
     would affect the other.

     I.14 EDITING LINE SEQUENCE NUMBERED FILES

     Some ASCII files have a  special  type  of  line  number  at  the
     beginning of each line.  These "line-sequence numbers" conform to
     certain rules so that they may be ignored or treated specially by
     compilers  and  other  programs.  The standards for line-sequence
     numbers are given in the LINED Program Reference Manual.

     TECO does not need line-sequence numbers for operation, but  TECO
     can  be  used  to  edit files containing them.  If such a file is
     edited with TECO-10, the line-sequence numbers are, in the normal
     case,  simply  preserved  as  additional text at the beginning of
     each line.  The line-sequence numbers may be deleted, edited, and
     inserted   exactly   like   any   other  text.   On  output,  the
     line-sequence numbers  are  output  according  to  the  standard,
     except  that  the  tab  after  the number is output only if it is
     already there.  Leading zeros are added as necessary.  If a  line
     without  a  line-sequence  number is encountered, a line-sequence
     number word of five spaces is placed  at  the  beginning  of  the
     line.

     The following switches are available for use  with  line-sequence
     numebred   files.    These  switches  are  merely  added  to  the
     appropriate file selection command.

     ERfilespec/SUPLSN`
     EBfilespec/SUPLSN`

     Standard TECO                                            PAGE 193
     Appendix I


     causes line sequence numbers to be suppressed at input time.  The
     numbers will not be read into the editing buffer.  Also, the tabs
     following the line-sequence  numbers,  if  they  exist,  will  be
     suppressed.

     EWfilespec/SUPLSN`

     causes the line-sequence numbers to be suppressed at output time.
     Tabs  following the line-sequence numbers will also be suppressed
     if they exist.

     EWfilespec/GENLSN`
     EBfilespec/GENLSN`

     causes line sequence numbers to be generated for the output  file
     if  they  did  not  already  exist  in the input file.  Generated
     line-sequence numbers begin at 00010 and continue with increments
     of 10 for each line.

     Note that these switches are needed only if a  change  is  to  be
     made  in the format of the file being edited.  If no switches are
     specified, a file is output in the same form as it was input.

     I.15 COMPILER RESTRICTIONS

     TECO-10 is a compiler rather than an  interpreter.   This  means,
     that  before your command string is executed, TECO-10 compiles it
     into assembly language code.  This makes it must faster than most
     other TECOs.  Before executing a macro (with the Mq command) TECO
     compiles the program in the macro.  The next time  the  macro  is
     executed, TECO notes that the macro has already been compiled and
     merely branches to the compiled code.  If  the  contents  of  the
     Q-register  are  changed (via an X or U command), then TECO notes
     that it must re-compile the commands  should  the  Q-register  be
     invoked as a macro.

     One consequence of this is that if a syntax error is detected  in
     a  command,  no  portion of that command will have been executed.
     For example, typing the command HK= will  yield  the  ?NAE  error
     message  and  the  text  buffer  will  NOT  be  cleared.  Another
     consequence of this is that you  must  not  invoke  a  macro  two
     different  times  using two different numbers of arguments.  If a
     macro  gets  initially  invoked  with  two  arguments,  then  all
     subsequent  invocations  must  supply  two arguments.  Also, TECO
     cannot tell while compiling an Mq  command  whether  or  not  the
     macro  returns  a  value.   Therefore  it assumes that a value is
     always  returned.   This  value  can  be  explicitly  removed  by
     followed  the  Mq command with an <ESCAPE>.  The MqA command will
     compile the A command as if it were an nA command rather than  an
     APPEND.

     Standard TECO                                            PAGE 194
     Appendix J


                                APPENDIX J


                     BASIC-PLUS/BASIC-PLUS-2 HANDLING


     J.1 PURPOSE

     In  BASIC-PLUS  and  BASIC-PLUS-2  a  program  statement  may  be
     continued over more than one text line.  A text line which is not
     the last text line of a given statement may need to be flagged as
     a  "continued"  line.   (See  the  appropriate language reference
     manual  for  requirements  of  each  version  of  each   language
     processor.)

     The standard continuation flag is the & character.  A line  which
     must  be  marked  as "continued" is written with an & as the last
     non-whitespace character before the <CR><LF>.

     (An older form of continuation was, in BASIC-PLUS  only,  to  end
     the text line by typing a <LF> key instead of <CR>.)

     The switches described in this appendix cause TECO to  manipulate
     the  text  files in such a way that each text line appears in the
     editing buffer to be completely "conventional":   that  is,  each
     text  line  ends with a standard <CR><LF>, and no text line has a
     trailing  &  character.   You  can  correctly  edit   well-formed
     BASIC-PLUS  or  BASIC-PLUS-2  source  files  without having to be
     concerned about continuation conventions.


     J.2 METHOD

     TECO allows you to work with "unemcumbered" lines in the  editing
     buffer  by removing continuation conventions as each text line is
     read  in.   You  indicate  that  you  want  this  processing   by
     specifying  a switch on the file specification supplied to the ER
     (or the EB) command.

     TECO (again) adds appropriate continuation  conventions  to  each
     text  line  as  it  is  written out from the editing buffer.  You
     indicate that you want this processing by specifying a switch  on
     the file specification supplied to the EW (or the EB) command.


     J.3 INPUT PROCESSING

     As TECO reads each new text line into the editing buffer,  it  is
     examined  for  a  trailing  &  character.   If one is found, TECO
     removes it, and then additionally  removes  any  trailing  spaces
     and/or tabs.

     (In the case of <LF> continuation, TECO  converts  that  kind  of

     Standard TECO                                            PAGE 195
     Appendix J


     line terminator character sequence to <CR><LF>.)

     The available switches follow.  (Consult the appropriate appendix
     to see which switches are supported on your operating system.)

            /B2    TECO strips trailing & sequences

            /n     Same as /B2 for input processing

            /B+    TECO changes <LF><CR><NUL>
                   sequences to <CR><LF>.


     J.4 OUTPUT PROCESSING

     As TECO writes each text line from the editing buffer, it takes a
     look  at  the text line which will follow.  If the following line
     begins with a digit, the current line is written without  change.
     If  the  following line does not begin with a digit, TECO assumes
     that the current line must be continued.

     The convention applied to an output text line which TECO marks as
     "continued"  depends  on  the  form  of  the  switch you specify.
     (Consult the appropriate  appendix  to  see  which  switches  are
     supported on your operating system.)

            /B2    TECO appends a space and an &

            /n     TECO appends an &, after padding out
                   the line with tabs and/or spaces to make
                   the & appear in column n

            /B+    TECO ends the line with a
                   <LF><CR><NUL> sequence
                   (instead of <CR><LF>.)


     J.5 FORM FEED INTERACTION

     When TECO reads a page of text into the editing buffer, it  stops
     when  a  <form feed> character is encountered, or when the buffer
     has been filled to capacity.  In the latter case, the  last  line
     will  be complete, and will include its line delimiter.  However,
     no look-ahead is done to examine the next line in the file.

     If TECO is being used with one of the switches described in  this
     appendix,  a  very  long BASIC-PLUS-x source program which is not
     segmented with <FF> characters can cause the  last  line  in  the
     buffer  to  not  be  the  last  text  line of a multi-line source
     statement.

     When the buffer is written to the output file, TECO has no way of
     determining  whether  the  next  text line (the first line of the

     Standard TECO                                            PAGE 196
     Appendix J


     next buffer load) will begin with a line number.  TECO makes  the
     assumption  that  the  buffer's  last  text  line  is  not  to be
     "continued", and terminates it with <CR><LF>.  If this assumption
     is  incorrect (frequently the case), remaining text lines of that
     multi-line  statement  will  be  lost   when   the   program   is
     subsequently OLDed.

     To  avoid  this  problem,  lengthy  BASIC-PLUS  or   BASIC-PLUS-2
     programs  should  be segmented with <form feed> characters before
     editing  them   using   these   TECO   switches.    Segments   of
     approximately  150  to  200 lines are convenient.  Starting a new
     page even more frequently to make listings readable isn't  a  bad
     idea, either.

     Standard TECO                                            PAGE 197
     Glossary


                      GLOSSARY OF OBSCURE TECO TERMS


     Accent grave
                    The `  character.   Echoed  for  TECO's  text  and
                    command  string delimiter when an ESCape surrogate
                    is  in  effect.   Actually  set  as   the   ESCape
                    surrogate by the 8192 ET bit.

     Abort-on-error bit
                    The 128's bit of the ET flag.  If this bit is set,
                    then  TECO will abort execution on encountering an
                    error  (after  printing  the  error  message)  and
                    control returns to the operating system.  This bit
                    is initially set when TECO starts up, but is reset
                    whenever TECO issues its prompt.

     <ALTMODE>      One  of  several  characters  that   TECO   treats
                    specially for use as a delimiter.  Known as ESCAPE
                    in more recent times, but traditional  TECO  users
                    will still go on ending their command strings with
                    "ALT" "ALT".

     Anchored search
                    A search (S) or search and  replace  (FS)  command
                    that is preceded by a ::.  This indicates that the
                    search  must  match  the  characters   immediately
                    following  the current pointer position.  If these
                    characters do not match, no further  searching  is
                    performed  and  the  text  buffer pointer does not
                    move.

     Argument pair  A command of the  form  m,n  where  m  and  n  are
                    numbers  (or  TECO  commands that return numbers).
                    When used before a command that normally  acts  on
                    lines,  the  argument  pair  causes the command to
                    work on characters.  The characters  specified  by
                    this  argument  pair  is  the  set  of  characters
                    between pointer positions m and n.  The  number  m
                    should normally be less than or equal to n.

     ASCII  code     The  American  Standard  Code   for   Information
                    Interchange.   The  code used by TECO to represent
                    characters internally.   Consult  Appendix  A  for
                    details.

     @-sign modified command
                    A command that is preceded by an @-sign modifier.

     @-sign modifier
                    An  at-sign  (@)  that  proceeds  a  command.   It
                    indicates  to TECO that the string argument to the
                    command  is  to  delimited  on  both  sides  by  a

     Standard TECO                                            PAGE 198
     Glossary


                    user-supplied   delimiter   rather   than   to  be
                    delimited only at the  end  by  a  TECO-designated
                    delimiter (normally <ESCAPE>).

     Automatic refresh
                    A  refresh  of  the  buffer  display   done   when
                    scrolling  is  active  (when 7:W is non-zero) just
                    before TECO issues its asterisk prompt.  Automatic
                    refresh can be disabled by the 128 ED bit.

     Automatic type out
                    The feature of TECO that causes lines of  text  to
                    be  automatically  typed  out.  The ES flag may be
                    used to control the automatic type  out  of  lines
                    after search commands, and the EV flag may be used
                    to cause automatic type out of lines after command
                    execution.

     Auto-trace mode
                    A mode that TECO goes into when the 4's bit of the
                    EH  (Help-level)  flag is set.  In this mode, TECO
                    will automatically print out the erroneous command
                    string after an error occurs.

     Backup protection
                    The process of preserving the user's original file
                    (as  a  backup) when editing that file with the EB
                    (Edit with Backup) command.

     Backwards searches
                    A search that proceeds in the backwards direction.
                    If  the  string being looked for does not occur at
                    the current pointer position, the pointer position
                    is  moved  back  one  character  and the search is
                    tried again.  This continues until the  string  is
                    found or until the boundary of the search has been
                    reached or until the beginning of the current text
                    buffer  has  been  reached.  Backward searches are
                    initiated by using a negative argument to a search
                    command  or  by  using an argument pair m,n with m
                    greater than n to an FB or FC command.

     Bounded searches
                    A search command that requires  searching  only  a
                    portion   of   the  text  buffer.   Of  particular
                    importance is the case  where  you  only  want  to
                    search  the  current  line  for  a  given  string.
                    Bounded searches are  accomplished  using  the  FB
                    command.

     Case flagging  A mode of TECO wherein, on type out, it will  flag
                    alphabetic  characters  (in  either upper or lower
                    case) by  preceding  them  with  a  single  quote.

     Standard TECO                                            PAGE 199
     Glossary


                    Lower  case  flagging  is  particularly  useful on
                    terminals that do not display  lower  case.   Case
                    flagging  is  controlled  by  EU,  the  case flag.
                    Setting EU to 0 sets  lower  case  flagging  mode;
                    setting EU to 1 sets upper case flagging mode, and
                    setting EU to -1 removes all case flagging.

     Character-oriented editor
                    An  editor  that  allows  modification  of  single
                    characters,  so  that  if  just one character of a
                    line is wrong, the entire line does not have to be
                    retyped.   TECO  is  a  character-oriented  editor
                    (although  it  has  a  number  of  facilities  for
                    dealing with text lines, too).

     Colon-modified command
                    A  command  that  is  preceded  by  a  colon   (:)
                    modifier.

     Colon-modifier
                    A colon preceding a TECO command, used to indicate
                    that  the  action  of  the  command  is to change.
                    Frequently indicates that the command is to return
                    a  value  (-1  if  the command succeeded, 0 if the
                    command failed).

     Command line   The current line of the  command  string  that  is
                    being typed into TECO.

     Command string scope editing
                    The feature of TECO that is enabled  when  editing
                    is  performed  on  a  CRT terminal.  In this mode,
                    typing  the  immediate  action  <DELETE>   command
                    causes  the  character  deleted  from  the command
                    string to physically disappear  from  the  screen.
                    Other  commands,  such  as  <CTRL/U>  also  behave
                    differently,  taking   best   advantage   of   the
                    properties of a video terminal.

     Command string
                    The string of  TECO  commands  that  is  currently
                    being  typed  into  TECO,  or  is  currently being
                    executed by TECO.

     Comment        An informative message used within a TECO program,
                    to  make  the  code  more  readable.   The comment
                    explains the meaning and purpose of the associated
                    TECO   commands.    The  comment  is  enclosed  in
                    exclamation marks.

     Compile-class command
                    A set  of  operating  systems  commands  (such  as
                    COMPILE)  that causes compilation (translation) of

     Standard TECO                                            PAGE 200
     Glossary


                    a source file written in a computer language  into
                    machine  instructions.   The EG` command is useful
                    to finish an editing session  and  re-execute  the
                    last  compile-class  command  (normally  a command
                    that compiles the file that was just edited).

     Conditional    A TECO language construct used to specify code  to
                    be   conditionally  executed  depending  upon  the
                    results of some test.  The most  general  form  of
                    the TECO conditional is
                              n"X <then-clause> | <else-clause> '
                    which tests the number n using  condition  X  (See
                    section 5.13 for details).  The commands specified
                    by the <then-clause> are executed if the condition
                    succeeds,  otherwise the commands specified by the
                    <else-clause> are executed.

     Control-character
                    An ASCII character whose  octal  code  is  in  the
                    range  0-37.   Usually  denoted  in this manual by
                    <CTRL/X> where X is the character whose ASCII code
                    is 100 (octal) greater than the ASCII code for the
                    control   character   being   represented.    TECO
                    displays  such  a character as ^X (Caret-X) except
                    for <TAB>, <LF>, <VT>, <FF>, AND <CR>  which  have
                    their normal display, and <ESC> which is displayed
                    as $ (dollar sign) or, if a user-designated ESCAPE
                    surrogate  is  in  effect,  as  `  (accent grave).
                    Anytime a single control-character, <CTRL/X> is  a
                    valid  TECO  command,  the two-character sequence,
                    ^X, may be used instead.

     <CTRL/C> trapping
                    A mode of operation  wherein  a  TECO  macro  will
                    regain control (rather than TECO) when <CTRL/C> or
                    <CTRL/C><CTRL/C> is typed on the  user's  terminal
                    to  abort execution of the current command string.
                    <CTRL/C>  trapping  is  enabled  by  setting   the
                    high-order bit of the ET flag.

     Current character
                    The character immediately  following  the  current
                    text buffer pointer position.

     Cursor         A visible  pattern  on  a  CRT  terminal  (usually
                    blinking)  that  would  specify  to  a  true scope
                    editor (like VTEDIT) the current location  of  the
                    text  buffer  pointer,  or which would specify the
                    location where subsequently typed characters would
                    be displayed.

     Standard TECO                                            PAGE 201
     Glossary


     <DELIM>        Terminology in this manual for an ESCape typed  at
                    the   console   and  passed  to  TECO.   On  newer
                    terminals, there  may  be  no  ESCape  key.   Some
                    versions   of   TECO   provide   for   an  "ESCape
                    surrogate", a  user-designated  key  which  is  to
                    cause transmission of an ESCape to TECO.  The term
                    <DELIM> is used to indicate an ESCape  transmitted
                    to TECO whether it was generated by the designated
                    "surrogate" key or by a  "real"  ESCape  key.   An
                    ESCape  types out as ` when a surrogate is active,
                    but as $ when no surrogate is active.

     Destructive search
                    A form of global search in  which  pages  of  text
                    that are passed over (because they did not contain
                    the  string  being  searched  for)  are  discarded
                    rather   than   written   to   the   output  file.
                    Destructive searches are initiated in TECO via use
                    of the _ command.

     Display editor
                    A true display editor is on which  makes  efficent
                    use  of  a CRT terminal or display scope.  Such an
                    editor maintains a "window" into  the  text  being
                    edited.   As characters are typed on the terminal,
                    these characters immediately are entered into  the
                    text  buffer and the window is immediately updated
                    to reflect this change.  With  the  help  of  some
                    macro  support,  TECO  can  be  made  to be a true
                    display editor.   A  more  modest  use  of  a  CRT
                    terminal  (and which requires no macro support) is
                    scrolling, q.v.

     Dot            A mnemonic for "the current  text  buffer  pointer
                    position".   Stems from the fact that the .  (dot,
                    or period) TECO command returns this number as its
                    value.

     E command      One of several two-character  TECO  commands  that
                    start with the letter 'E'.

     Echo mode      A normal mode of  operation  in  which  TECO  will
                    automatically  echo  (display) each character that
                    is typed in response to a ^T command.  Opposite of
                    no-echo  mode.  This mode is controlled by the 8's
                    bit of the ET flag.  (0 means no-echo mode.)

     ED flag        The edit level flag.

     Edit-class command
                    A type of operating system command (such  as  MAKE
                    and  TECO)  that specifies that file editing is to
                    occur.   Many  operating  systems   remember   the

     Standard TECO                                            PAGE 202
     Glossary


                    argument   specified   with  the  last  Edit-class
                    command, so  that  the  next  time  an  edit-class
                    command  is used without an argument, the previous
                    argument can be recalled.

     Edit level flag
                    A bit-encoded flag, referenced by the ED  command,
                    that   describes   how  TECO  should  behave  with
                    reference to certain features.  See  section  5.16
                    for more details.

     Edit verify flag
                    A flag that describes how TECO  should  act  after
                    processing  of a command string.  This flag can be
                    set so that TECO will display the line just edited
                    on  the  terminal after each command.  See section
                    5.16 for more details.

     EH flag        The help level flag.

     Either-case search mode
                    A standard mode of operation in  which  alphabetic
                    characters  specified  within  a search string are
                    permitted to match a  corresponding  character  of
                    either upper or lower case.

     Else-clause    The part of a conditional command that is executed
                    if the condition is not satisfied.  In TECO, these
                    are the commands that occur between the | and  the
                    ' characters within the conditional construct.

     End-of-file flag
                    A read-only flag, referenced  by  the  ^N  command
                    that specifies whether or not end-of-file has been
                    seen on the currently selected  input  stream.   A
                    value  of  0  means  that end-of-file has not been
                    seen;  a value of -1 means  that  end-of-file  has
                    been  reached.   This  flag  is initially 0 and is
                    reset to 0 each time a new file  is  selected  for
                    input.

     EO level       The current version level of TECO-10.

     ES flag        The search verification flag.

     <ESCAPE>       The character whose ASCII code is 33 (octal).   It
                    is  a  general-purpose  delimiter  used  by  TECO.
                    Traditionally known  as  an  <ALTMODE>.   When  no
                    ESCape surrogate is active, an ESCape types out as
                    $ (dollar sign).  See also <DELIM>.

     Standard TECO                                            PAGE 203
     Glossary


     ESCape surrogate
                    A character (designated via the 8192  ET  bit,  or
                    via  the  EE  flag)  which  causes an ESCape to be
                    transmitted to TECO.  When an ESCape surrogate  is
                    active,  an  ESCape types out as ` (accent grave).
                    See also <DELIM>.

     ET flag        The terminal characteristics flag

     EU flag        The upper/lower case flag.

     EV flag        The edit verify flag.

     Exact-case search mode
                    A mode of operation in which alphabetic characters
                    within  a  search string must match the exact case
                    (upper  case  or   lower   case)   of   characters
                    specified.

     Exit Protection
                    A protective feature of TECO that prevents a  user
                    from  exiting  TECO  if a potential los of data is
                    imminent.  The EX  and  EG  commands  are  aborted
                    (with  the ?NFO error message) if there is text in
                    the text buffer, but no output file is open.

     F command      One of several two-character  TECO  commands  that
                    start with the letter 'F'.

     Flag           A data register used by TECO  to  control  various
                    modes  of operation.  The contents of the flag are
                    set by specifying the new value  before  the  flag
                    name;   and the contents are returned by using the
                    flag name without a numeric  argument.   The  TECO
                    flags  are:   ^X,  ^E, ^N, ED, EE, EH, EO, ES, ET,
                    EU, and EV.

     Flow command   A TECO-11 command that is used to flow (branch) to
                    a  particular  flow  control  character.  The flow
                    commands are F<, F>, F', and F|.

     Form feed flag
                    A read-only flag, referenced  by  the  ^E  command
                    that  specifies  whether  the previous append from
                    the input file terminated because of  encountering
                    a  form  feed  character  in  the  input  file, or
                    because the text buffer became nearly  full.   The
                    value  of  this flag is automatically set to -1 by
                    TECO if input is terminated by the presence  of  a
                    form feed character in the input file.

     Standard TECO                                            PAGE 204
     Glossary


     Garbage collection
                    A process used by TECO-10 to collect unused memory
                    when more memory is required.

     Global Q-register
                    A Q-register available throughout all macro levels
                    (including "outside", or at prompt level).  Global
                    Q-registers are named A-Z and 0-9.  See also Local
                    Q-Registers, and section 3.3.2.

     Global search  A type of search that continues through the entire
                    input  file  until  the  specified  characters are
                    found.  Successive pages of the file are read into
                    the  text  buffer  and  then  written out into the
                    output  file  (if  the  string  is  not  located).
                    Global  searches  in  TECO are initiated via the N
                    command.

     Hard-copy editing mode
                    A mode of operation that TECO uses when the user's
                    terminal  is  not  a  CRT.   In  this mode, when a
                    character is rubbed out using  the  <DELETE>  key,
                    the   rubbed-out  character  is  re-typed  on  the
                    terminal  as  a  visible  indication   that   this
                    character  was  rubbed  out.   Opposite  of  scope
                    editing mode.  This mode can be entered, even on a
                    scope  terminal, by turning off the 2's bit of the
                    ET flag.

     Help level flag
                    A bit-encoded flag, referenced by the EH  command,
                    that controls properties of TECO having to do with
                    error messages and user assistance.

     Immediate command
                    A special command to  TECO  that  takes  immediate
                    effect,   requiring   no  <DELIM>s  to  begin  its
                    execution.

                    "Immediate action editing characters" are commands
                    such  as  <DELETE>  and  <CTRL/U>,  which  perform
                    editing of the TECO command string currently being
                    typed in.  See section 4.1.

                    An   "immediate   inspection   command"    is    a
                    single-character command which can be typed as the
                    very  first  character  after   TECO's   prompting
                    asterisk,  and  which  causes the current location
                    counter to be  moved  by  one  line  and  the  new
                    current  line  to be typed out.  Examples are <LF>
                    and <BS>.  See section 1.6.1.

                    "Immediate action  commands"  are  other  commands

     Standard TECO                                            PAGE 205
     Glossary


                    which  may  be  typed right after TECO's prompting
                    asterisk,   such   as   the   *q   to   save   the
                    previously-typed command in a Q-register or the ^W
                    to re-display  a  scrolling  buffer  window.   See
                    section 4.2.

                    "Immediate ESCape sequence" commands  are  invoked
                    by  keys  which generate escape sequences, such as
                    "arrow" or "auxiliary keypad" keys.   See  section
                    4.4.   Such  commands  are usually used to perform
                    editing of the TECO command string currently being
                    entered  into  TECO.   For  example,  the commands
                    <DELETE>  and  <CTRL/U>   are   immediate   action
                    commands.

     Iteration      A language construct that permits  a  sequence  of
                    operations  to  be  re-executed  indefinitely or a
                    given  number  of  times.   In   TECO,   this   is
                    accomplished  by  enclosing  the commands in angle
                    brackets.

     Kernel         The TECO-11 kernel refers to  the  TECO-11  module
                    that implements all those features of TECO-11 that
                    are  common  to  all  PDP-11  operating   systems.
                    Operating   system   specific   features  and  the
                    interface to the operating system is  accomplished
                    by  linking an I/O module tailored for the desired
                    operating system with the kernel.

     Keypad editor  A true scope editor that uses special keys on  the
                    terminal  (such  as  a  VT52  or VT100) to control
                    editing functions.  VTEDIT  is  an  example  of  a
                    keypad editor.

     Line           A portion of text delimited by <LF>,  <VT>,  <FF>,
                    or  the  beginning or end of the text buffer.  The
                    final delimiter is considered to be  part  of  the
                    line.

     Line-numbered file
                    In TOPS-10,  an  ASCII  file  that  contains  line
                    numbers  embedded in the start of each line.  TECO
                    does not  require  these  line  numbers,  but  can
                    handle them if they are present.  They can also be
                    generated  or  suppressed  via  the  /GENLSN   and
                    /SUPLSN switches respectively.

     Line-oriented editor
                    An editor that  primarily  uses  line  numbers  to
                    direct  editing,  and  most  of whose commands are
                    line-oriented.   TECO  is   a   character-oriented
                    editor,  but  also  has  many facilities that work
                    with lines.

     Standard TECO                                            PAGE 206
     Glossary


     Line-wrap mode
                    A standard mode of TECO's window  support  wherein
                    lines  that  are  too  long  to  fit  on  a single
                    physical  line  of   the   user's   terminal   are
                    automatically   continued   on   the   next  line.
                    Opposite of truncate mode.

     Literal type out mode
                    A mode that TECO can be put into  by  setting  the
                    1's bit in the ET flag, or (for a single character
                    on a one-shot basis) by using the :^T command.  In
                    this  mode, any characters typed by a TECO program
                    via use of one of the commands T, V,  ^A,  or  :G,
                    will  be  displayed on the user's terminal without
                    any modification.  When not  in  this  mode,  TECO
                    will convert characters that normally do not print
                    to a form that can  be  displayed  on  the  user's
                    terminal   (e.g.   <CTRL/X>  displays  as  ^X  and
                    <ESCAPE> displays as $ or,  if  a  user-designated
                    ESCAPE  surrogate  is  in  effect, as `).  Literal
                    type  out  mode  is  useful  when  trying  to   do
                    real-time  displays  on  a  CRT  terminal.  Normal
                    (up-arrow) mode is particularly useful to let  you
                    see what characters are really in your file.

     Local Q-register
                    A Q-register available  to  only  a  single  macro
                    level  (including  "outside", or at prompt level).
                    The local Q-registers for a particular macro level
                    are  automatically  saved  and  restored  by  TECO
                    around execution of a  lower-level  macro.   Local
                    Q-registers  are  named .A-.Z and .0-.9.  See also
                    Global Q-Registers, and section 3.3.2.

     Log file       An audit trail that TECO-10 can keep  showing  all
                    the  commands  that  were typed to TECO and/or all
                    the type out made by TECO.   This  is  useful  for
                    reviewing  what went wrong with a 'bad' edit.  The
                    log file is initiated with  the  EL  command  (see
                    Appendix C).

     Macro          A sequence of TECO commands intended to be  loaded
                    into a Q-register and executed as a TECO program.

     Macro level    Two commands within the same TECO macro  are  said
                    to  be  at  the  same  macro level.  When one TECO
                    macro calls another, the calling macro is said  to
                    be at the higher macro level, and the called macro
                    at the lower macro level.

     Match control construct
                    A   command,   consisting   of   certain   special
                    characters,   used   within  a  search  string  to

     Standard TECO                                            PAGE 207
     Glossary


                    indicate to TECO that special groups of characters
                    are permitted to match at this point.

     Memory expansion
                    TECO's act of acquiring  additional  storage  from
                    the  operating system when the currently allocated
                    storage is insufficient to handle the current TECO
                    command.   Typically, TECO will attempt to acquire
                    this additional memory before it  completely  runs
                    out  of memory, so as to allow a 'buffer zone' for
                    the user.  This allows him to complete a few  more
                    commands  even in the case where TECO is unable to
                    get more memory.   The  informative  message  "[nK
                    Bytes]"  or  its  equivalent  is  printed  on  the
                    terminal informing the user that memory usage  has
                    expanded.

     Mung           A recursive acronym for "Mung Until No Good";   an
                    act  applied  by novice TECO users to their source
                    files.

     MUNG command   An operating  system  command  used  to  invoke  a
                    pre-written  TECO  program.  The most general form
                    of this command is "MUNG file,data"  where  "file"
                    is  the  name of a TECO source program, and "data"
                    is data to be passed to that program.

     No-echo mode   A  mode  of  operation  in  which  TECO  will  not
                    automatically  echo  (display) the character typed
                    by the user in response to the ^T  command.   This
                    mode  is  entered by setting the 8's bit of the ET
                    flag.  Opposite of echo mode.

     Page           A portion of text delimited by  form  feeds.   The
                    form  feeds  are  not considered to be part of the
                    page.  Sometimes the term 'page' is used to  refer
                    to all the text currently in the text buffer.

     Panic Mode     A condition that  occurs  (on  small,  single-user
                    operating   systems),   when,  in  the  middle  of
                    outputting during an edit, the output device fills
                    up so that the I/O transfer cannot continue.  TECO
                    recovers  gracefully  from   this   condition   by
                    printing  the  ?FUL  error  message  and returning
                    control to TECO without any loss of data.  At this
                    point, the user closes the current output file and
                    opens another one on  another  device  (with  more
                    room)  and resumes editing.  At a subsequent time,
                    the two parts of his file can be concatenated back
                    together.

     Standard TECO                                            PAGE 208
     Glossary


     Pipeline editor
                    An editor which only makes sequential edits  to  a
                    file.  The file to be edited is read into the text
                    buffer one piece at a time.  Each piece is  edited
                    and  then  written  out.   Once  a  piece has been
                    written out, further editing to that piece is  not
                    possible  unless the output file is re-opened in a
                    later edit as a new file to be edited.  TECOs  are
                    pipeline editors, with the exception of TECO-11 on
                    VAX/VMS  (which  offers  the  capability  to  page
                    backwards as well as forward).

     Pointer preservation mode
                    A mode of  operation  in  which  the  text  buffer
                    pointer  will  not  change after a failing search.
                    This mode is controlled by the 16's bit of the  ED
                    flag.

     Primary input stream
                    A term used by TECO-11 to refer to the main  input
                    file that TECO is using.

     Primary output stream
                    A term used by TECO-11 to refer to the main output
                    file that TECO is using.

     Prompt level   A TECO command is said to be executed from  prompt
                    level  if  it was typed in directly in response to
                    TECO's prompt, as opposed to being executed from a
                    macro.

     Q-register     One of  36  global  or  36  local  user-accessible
                    registers  provided  by TECO.  Each Q-register can
                    hold both a number  and  a  string  of  text.   Of
                    particular importance is the ability to store TECO
                    command strings  in  Q-registers  to  be  used  as
                    "macros".

     Q-register push down list
                    A last-in first-out stack available to  users  for
                    saving and restoring the contents of Q-registers.

     Read-with-no-wait mode
                    A mode of operation in which the ^T  command  will
                    not  hang  until  a  key  is  typed  on the user's
                    terminal.  In  this  mode,  if  no  key  has  been
                    struck,  TECO  returns a -1 as the value of the ^T
                    command.  This mode is entered by setting the 32's
                    bit of the ET flag.

     Scrolling      A  form  of  TECO  operation  available   on   CRT
                    terminals   capable   of  supporting  split-screen
                    operation.  The bottom n lines are used for TECO's

     Standard TECO                                            PAGE 209
     Glossary


                    asterisk prompt and the usual typed command lines;
                    the  remaining  lines  above  are  used   for   an
                    automatically-updated window into the text buffer.
                    A valuable training aid:  one can experiment  with
                    TECO   commands   and  immediately  observe  their
                    effects.  Not  a  bad  idea  for  advanced  users,
                    either.  Controlled by the n,7:W command.

     SEALL mode     A mode of window operation in which all characters
                    have  a  distinctive  visible  display,  including
                    characters such as <TAB>, <CR>,  and  <LF>,  which
                    normally do not print.  Controlled by the 3:W flag
                    (see section 5.17).   Also  known  as  "View  all"
                    mode.

     Search verification flag
                    A  flag,  referenced  by  the  ES  command,   that
                    controls  the  action  of  TECO  subsequent to the
                    execution of a command string  containg  a  search
                    command.   Proper setting of this flag will enable
                    the user to verify that  the  search  located  the
                    correct  string, by having the line containing the
                    string  found  displayed  on  the  terminal.   See
                    section 5.16 for more details.

     Search mode flag
                    A  flag,  referenced  by  the  ^X  command,   that
                    controls  how  TECO treats alphabetical characters
                    within search strings.  This flag is used  to  put
                    TECO  into  either exact-case mode, or either-case
                    mode.  If the ^X flag is set  to  0,  then  either
                    case  matches  in searches.  If the ^X flag is set
                    to 1, then exact case matches are required.

     Secondary input stream
                    A term used by TECO-11 to refer  to  an  auxiliary
                    input  "channel"  that was formed by use of the EP
                    command.

     Secondary output stream
                    A term used by TECO-11 to refer  to  an  auxiliary
                    output  "channel" that was formed by use of the EA
                    command.  See section 5.1.4 for details.

     Scope editing mode
                    A mode of TECO in which command line scope editing
                    (q.v.)  algorithms are used.  This mode is enabled
                    by setting the 2's bit of  the  ET  flag.   It  is
                    usually  automatically  enabled  by  TECO  if  the
                    operating system can  detect  that  the  user  has
                    invoked  TECO  from a scope terminal.  Opposite of
                    hard-copy editing mode.

     Standard TECO                                            PAGE 210
     Glossary


     Split Q-registers
                    The feature of TECO that permits storing of both a
                    number  and  a  string  within a Q-register.  Each
                    Q-register can be considered  to  consist  of  two
                    compartments.

     String build construct
                    A command, consisting of special characters,  used
                    within a text argument to build up the contents of
                    the text argument from other components.

     SUPER TECO mode
                    A mode of TECO-8 wherein TECO will read  past  the
                    end-of-file  mark  (CTRL/Z)  of a sequential ASCII
                    file.  This mode is enabled by using the /S switch
                    on  an  ER or EB command and is terminated when an
                    ER or EB command is  issued  with  no  /S  switch.
                    This  mode  is  useful  for  scanning through mass
                    storage devices in an attempt to recover data from
                    files that had previously been deleted.

     Switch         A construct of the  form  /SWITCH  used  within  a
                    command  that takes a filespecification, to modify
                    the action of the command  or  attributes  of  the
                    file specified.  Also known as a qualifier.

     Tag            A label specified within exclamation marks to mark
                    a  point  within  a  TECO program.  Control can be
                    transferred to this point by the  use  of  a  GOTO
                    (Otag`) command.

     TECO           Text Editor and COrrector program.

     TECO.INI       A file containing TECO commands that is used as  a
                    user's  private  initialization  file.   When TECO
                    starts up, it looks for such a file in the  user's
                    area,  and  if  it finds one, the TECO commands in
                    this file are executed before editing commences.

     TECO.TEC       A TECO macro used by  many  operating  systems  to
                    parse the user's edit-class commands.

     TECO I/O mode  A mode of  I/O  operation  under  the  RSTS/E  and
                    RSX-11  operating  systems,  in  which  the system
                    buffers most characters and returns control to the
                    caller   (usually   TECO)  only  when  interesting
                    characters (such as <DELETE>, <DELIM>,  etc.)  are
                    typed.

     TECO's prompt  refers to the asterisk (*)  that  TECO  prints  to
                    indicate that it is ready to accept commands.

     Standard TECO                                            PAGE 211
     Glossary


     TECO SIG       A DECUS  Special  Interest  Group,  consisting  of
                    users   who   are  dedicated  to  the  spread  of,
                    improvement of, and standardization of TECO.

     Terminal characteristics flag
                    A bit-encoded flag, referenced via the ET command,
                    that contains information about the user's console
                    terminal and specifies in what manner TECO  should
                    support it.

     Text buffer
                    The main buffer used by TECO to hold the  text  to
                    be edited.

     Text buffer pointer
                    A pointer that marks the position within the  text
                    buffer where TECO is currently 'at'.  This pointer
                    always points to positions between characters;  it
                    never   points   at   a  character.   The  current
                    character  is  considred  to  be   the   character
                    immediately  to  the right of the current position
                    of the text buffer pointer.

     Then-clause    The set of commands within a conditional that  are
                    executed  if the condition is satisfied.  In TECO,
                    these commands immediately follow the  "X  at  the
                    start  of the conditional.  They are terminated by
                    a | or ' character.

     Tracing        The  act  of   watching   the   command-by-command
                    execution of a TECO program.  This is accomplished
                    by putting TECO into trace mode, via use of the  ?
                    command.

     Trace mode     A mode  of  TECO  wherein  each  command  that  is
                    executed  by  TECO is also displayed on the user's
                    terminal as it is being executed.   This  mode  is
                    useful  for  debugging  complicated TECO programs.
                    TECO is toggled in and out of this mode via use of
                    the  ?   command.   See  section  5.18.4  for more
                    details.

     Truncate mode  A mode of TECO's window support wherein lines that
                    are  too  long to fit on a single physical line of
                    the user's terminal are truncated when  the  right
                    margin  of the scope is encountered.  This mode is
                    entered by setting the 256's bit in the  ET  flag.
                    Opposite of line-wrap mode.

     Type-out-time command
                    A special command that makes sense only while TECO
                    is   typing  out  text  on  the  terminal.   These
                    commands are <CTRL/S>, <CTRL/Q>, and <CTRL/O>  and

     Standard TECO                                            PAGE 212
     Glossary


                    affect the type out.

     Up-arrow mode  A standard mode of  operation  wherein  upon  type
                    out,  TECO  will  display  control  characters  by
                    typing the visible two-character  sequence  ^X  to
                    represent the control character <CTRL/X>.  On many
                    older terminals, the caret  character  (^),  whose
                    octal  ASCII  code  is 136, prints as an up-arrow.
                    Some  control  characters  are  not   printed   in
                    up-arrow  mode,  notably  <TAB>, <LF>, <VT>, <FF>,
                    and <CR>.

     Upper/lower case flag
                    A  flag,  referenced  by  the  EU  command,   that
                    specifies  whether  or  not  case  flagging  is to
                    occur.  If set to -1, no case flagging occurs.  If
                    set  to  0,  lower  case characters are flagged on
                    type out.  If set to +1, upper case characters are
                    flagged on type out.

     View all mode  A mode of window operation in which all characters
                    have  a  distinctive  visible  display,  including
                    characters such as <TAB>, <CR>,  and  <LF>,  which
                    normally do not print.  Controlled by the 3:W flag
                    (see section 5.17).  Also known as SEALL mode.

     War and Peace mode
                    A mode of operation in which TECO outputs a  large
                    informative paragraph of information automatically
                    upon encountering an error in  a  user's  program.
                    This  paragraph of information describes the error
                    in painstaking detail and tells the  user  how  to
                    recover.  This mode is entered by setting the help
                    level to 3.  This mode is particularly  useful  to
                    Novices and particularly obnoxious to experts.

     Window         The portion of the text buffer that  is  currently
                    being   displayed   on   the  user's  terminal  or
                    auxiliary display device.

     Window support
                    Assembly language  code,  built  into  TECO,  that
                    maintains  a  window  into  the text buffer on the
                    user's terminal or auxiliary display device.

     Yank protection
                    A feature of TECO wherein any Y, _, or F_  command
                    that   will  potentially  destroy  valid  data  is
                    aborted.  This mode is normally enabled  and  will
                    cause  any of the aforementioned commands to abort
                    with the ?YCA error message if there  is  text  in
                    the  text buffer and an output file is open.  This
                    feature can be disabled by turning off the 2's bit

     Standard TECO                                            PAGE 213
     Glossary


                    in the ED flag.

     Standard TECO                                            PAGE 214
     Index


                         INDEX TO TECO COMMANDS
                         AND SPECIAL CHARACTERS


      NULL   Discarded on input; Ignored in comman  . . 119
      ^A     Output message to terminal . . . . . . . . 64
      ^B     Current date . . . . . . . . . . . . . . . 90
      ^C     Stop execution . . . . . . . . . . . . . . 40, 53, 99
      ^D     Set radix to decimal . . . . . . . . . . . 87
      ^E     Form Feed flag . . . . . . . . . . . . . . 90
      ^E<n>  (Match char) Match ASCII code n  . . . . . 79
      ^EA    (Match char) Match alphabetics . . . . . . 78
      ^EB    (Match char) Match separator char  . . . . 78
      ^EC    (Match char) Match Symbol Constituent  . . 78
      ^ED    (Match char) Match numerics  . . . . . . . 78
      ^EGq   (Match char) Match contents of Q-reg   . . 78
      ^EL    (Match char) Match line terminators  . . . 78
      ^EMx   (Match char) Match any number of x . . . . 78
      ^EQq   (String char) Use contents of Q-reg q  . . 77
      ^ER    (Match char) Match alphanumerics . . . . . 78
      ^ES    (Match char) Match non-null space/tab  . . 78
      ^EUq   (String char) Use ASCII code in Q-reg  . . 77
      ^EV    (Match char) Match lower case alphabe  . . 78
      ^EW    (Match char) Match upper case alphabe  . . 78
      ^EX    (Match char) Match any character . . . . . 79
      ^E[]   (Match char) Match one of list . . . . . . 79
      ^F     Contents of console switch register  . . . 90
      n^F    Return terminal number of job n  . . . . . 91
      ^G^G   Kill command string  . . . . . . . . . . . 40
      ^G<sp> Retype current command line  . . . . . . . 40
      ^G*    Retype current command input . . . . . . . 40
      ^H     Current time of day  . . . . . . . . . . . 91
      BS     Back up and type one line  . . . . . . . . 17, 41
      TAB    Insert tab and text  . . . . . . . . . . . 69
      LF     Line terminator; Ignored in commands . . . 9, 34, 117
      LF     Advance and type one line  . . . . . . . . 17, 41
      VT     Line terminator; Not a TECO command  . . . 34
      FF     Page terminator; Output Form Feed  . . . . 9, 34
      CR     End input line; Ignored in commands  . . . 9, 40, 117
      ^N     End of file flag . . . . . . . . . . . . . 91
      ^Nx    (Match char) Match all but x . . . . . . . 77
      ^O     Set radix to octal . . . . . . . . . . . . 87
      ^O     Kill terminal output . . . . . . . . . . . 65
      ^P     Not a TECO command . . . . . . . . . . . . 214
      ^Q     Resume terminal output . . . . . . . . . . 65
      ^Q     Convert line arg into character arg  . . . 146, 150
      ^Qx    (String char) Use x literally  . . . . . . 76
      ^R     Value of current radix . . . . . . . . . . 87
      n^R    Set radix to n . . . . . . . . . . . . . . 87
      ^Rx    (String char) Use x literally  . . . . . . 76
      ^S     -(length) of last referenced string  . . . 91
      ^S     Suspend terminal output  . . . . . . . . . 65
      ^S     Save last command string . . . . . . . . . 149

     Standard TECO                                            PAGE 215
     Index


      ^S     (Match char) Match separator char  . . . . 77
      ^T     ASCII value of next character typed  . . . 91
      ^T     Read and decode next keystroke typed . . . 91
      n^T    Type ASCII character of value n  . . . . . 63
      n:^T	Output binary byte of value n  . . . . . . . 63
      ^U     Kill command line  . . . . . . . . . . . . 40
      ^Uq    Put string into Q-register q . . . . . . . 80
      :^Uq   Append string to Q-register q  . . . . . . 81
      n^Uq   Put ASCII char "n" into Q-register q . . . 81
      n:^Uq  Append ASCII char "n" to Q-register q  . . 81
      ^V     Enable lower case conversion . . . . . . . 121
      ^Vx    (String char) Force x to lower case  . . . 76
      ^W     Enable upper case conversion . . . . . . . 121
      ^W     Refresh scrolled display . . . . . . . . . 41
      ^Wx    (String char) Force x to upper case  . . . 76
      ^X     Search mode flag . . . . . . . . . . . . . 112
      ^X     (Match char) Match any character . . . . . 77
      ^Y     Equivalent to ".+^S,." . . . . . . . . . . 92
      ^Z     Size of text in all Q-registers  . . . . . 92
      ^Z^Z^Z Immediate exit from TECO . . . . . . . . . 40
      ESC    String and command terminator  . . . . . . 7, 39, 99
      ESC    String and command terminator  . . . . . . 119
      ^[     String and command terminator  . . . . . . 119
      ^\     Not a TECO command . . . . . . . . . . . . 214
      ^]     Not a TECO command . . . . . . . . . . . . 214
      ^^x    ASCII value of x . . . . . . . . . . . . . 92
      ^_     Ones complement (logical NOT)  . . . . . . 86
      SP     Ignored in commands  . . . . . . . . . . . 117
      !      Define label . . . . . . . . . . . . . . . 95
      "      Start conditional  . . . . . . . . . . . . 101
      n"<    Test for less than zero  . . . . . . . . . 102
      n"=    Test for equal to zero . . . . . . . . . . 102
      n">    Test for greater than zero . . . . . . . . 102
      n"A    Test for alphabetic  . . . . . . . . . . . 101
      n"C    Test for symbol constituent  . . . . . . . 101
      n"D    Test for numeric . . . . . . . . . . . . . 102
      n"E    Test for equal to zero . . . . . . . . . . 102
      n"F    Test for false . . . . . . . . . . . . . . 102
      n"G    Test for greater than zero . . . . . . . . 102
      n"L    Test for less than zero  . . . . . . . . . 102
      n"N    Test for not equal to zero . . . . . . . . 102
      n"R    Test for alphanumeric  . . . . . . . . . . 102
      n"S    Test for successful  . . . . . . . . . . . 102
      n"T    Test for true  . . . . . . . . . . . . . . 102
      n"U    Test for unsuccessful  . . . . . . . . . . 102
      n"V    Test for lower case  . . . . . . . . . . . 102
      n"W    Test for upper case  . . . . . . . . . . . 102
      #      Logical OR . . . . . . . . . . . . . . . . 86
      $      Separate TECO commands . . . . . . . . . . 120
      $      ESCape (no surrogate) typeout  . . . . . . 3
      n%q    Add n to Q-register q and return resu  . . 80
      &      Logical AND  . . . . . . . . . . . . . . . 86
      '      End conditional  . . . . . . . . . . . . . 101

     Standard TECO                                            PAGE 216
     Index


      (      Expression grouping  . . . . . . . . . . . 86
      )      Expression grouping  . . . . . . . . . . . 86
      *      Multiplication . . . . . . . . . . . . . . 86
      *q     Save last command in Q-register q  . . . . 42
      +      Addition . . . . . . . . . . . . . . . . . 86
      ,      Argument separator . . . . . . . . . . . . 86
      -      Subtraction or negation  . . . . . . . . . 86
      .      Current pointer position . . . . . . . . . 89
      /      Division . . . . . . . . . . . . . . . . . 86
      /      Type detailed explanation of error . . . . 41
      0-9    Digit  . . . . . . . . . . . . . . . . . . 214
      :      Modify next command  . . . . . . . . . . . 33
      ;      Exit iteration on search failure . . . . . 97
      n;     Exit iteration if n is positive  . . . . . 97
      :;     Exit iteration on search success . . . . . 97
      n:;    Exit iteration if n is negative  . . . . . 97
      n<     Iterate n times  . . . . . . . . . . . . . 94
      =      Type in decimal  . . . . . . . . . . . . . 87
      ==     Type in octal  . . . . . . . . . . . . . . 87
      ===    Type in hexadecimal  . . . . . . . . . . . 87
      :=     Type in decimal, no carriage return  . . . 87
      :==    Type in octal, no carriage return  . . . . 87
      :===   Type in hexadecimal, no carriage retu  . . 87
      >      End iteration  . . . . . . . . . . . . . . 94
      ?      Toggle trace mode  . . . . . . . . . . . . 119
      ?      Type out command string in error . . . . . 41
      @      Modify next text argument  . . . . . . . . 33
      A      Append to buffer . . . . . . . . . . . . . 58
      nA     ASCII value of char in buffer  . . . . . . 89
      n:A    Append n lines to buffer . . . . . . . . . 58
      B      0 - beginning of buffer  . . . . . . . . . 89
      nC     Advance n characters . . . . . . . . . . . 61
      nD     Delete n characters  . . . . . . . . . . . 66
      m,nD   Delete between m and n . . . . . . . . . . 66
      DELIM  Character typed as surrogate for ESCa  . . 2, 7, 30, 39, 107, 111
      DELIM  Advance and type one line  . . . . . . . . 17, 41
      E%q    Write Q-register q into a file . . . . . . 57
      EA     Select secondary output stream . . . . . . 54
      EB     Open input and output  . . . . . . . . . . 49
      EC     Close out (copy in to out and close) . . . 52
      ED     Edit mode flag . . . . . . . . . . . . . . 105
      EE     ESCape surrogate character . . . . . . . . 107
      EF     Close output file  . . . . . . . . . . . . 52
      EG     Close out and exit with command  . . . . . 52
      :EG    Execute operating system function  . . . . 52, 148, 149
      EH     Help level flag  . . . . . . . . . . . . . 107
      EI     Open indirect command file . . . . . . . . 54
      m,nEJ  Set environment characteristics  . . . . . 104
      nEJ    Return environment characteristics . . . . 103
      EK     Kill output file . . . . . . . . . . . . . 53
      EL     Open log file  . . . . . . . . . . . . . . 53
      nEM    Position magtape . . . . . . . . . . . . . 150
      EN     Wildcard lookup  . . . . . . . . . . . . . 56

     Standard TECO                                            PAGE 217
     Index


      EO     Version of TECO  . . . . . . . . . . . . . 93
      nEO    Set TECO to function as version n  . . . . 108
      EP     Select secondary input stream  . . . . . . 54
      EQq    Read file into Q-register q  . . . . . . . 56
      ER     Open input file  . . . . . . . . . . . . . 49, 54
      ES     Search verification flag . . . . . . . . . 108
      ET     Type out control flag  . . . . . . . . . . 109
      EU     Case flagging flag . . . . . . . . . . . . 112
      EV     Edit verify flag . . . . . . . . . . . . . 112
      EW     Open output file . . . . . . . . . . . . . 50, 54
      EX     Close out and exit . . . . . . . . . . . . 53
      EY     Read without yank protection . . . . . . . 60
      EZ     Zero output tape . . . . . . . . . . . . . 53
      nE_    Search without yank protection . . . . . . 72
      F'     Flow to end of conditional . . . . . . . . 98
      F<     Flow to start of iteration . . . . . . . . 98
      F>     Flow to end of iteration . . . . . . . . . 98
      F|     Flow to ELSE part of conditional . . . . . 99
      m,nFB  Search between locations m and n . . . . . 73
      nFB    Search, bounded by n lines . . . . . . . . 73
      m,nFC  Search and replace between m and n . . . . 74
      nFC    Search and replace over n lines  . . . . . 74
      nFD    Search and delete string . . . . . . . . . 66, 74
      nFK    Search and delete intervening text . . . . 67, 74
      nFN    Global string replace  . . . . . . . . . . 73
      FR     Replace last string  . . . . . . . . . . . 69
      nFS    Local string replace . . . . . . . . . . . 73
      nF_    Destructive search and replace . . . . . . 74
      Gq     Get string from Q-register q into buf  . . 83
      G*     Get last filespec string into buffer . . . 145
      :Gq    Type Q-register q on terminal  . . . . . . 83
      G_     Get last search string into buffer . . . . 146
      H      Equivalent to "B,Z"  . . . . . . . . . . . 89
      I      Insert text  . . . . . . . . . . . . . . . 68
      nI     Insert ASCII character "n" . . . . . . . . 68
      nJ     Move pointer to "n"  . . . . . . . . . . . 61
      nK     Kill n lines . . . . . . . . . . . . . . . 66
      m,nK   Delete between m and n . . . . . . . . . . 67
      nL     Advance n lines  . . . . . . . . . . . . . 62
      Mq     Execute string in Q-register q . . . . . . 84, 90
      nN     Global search  . . . . . . . . . . . . . . 72
      O      Go to label  . . . . . . . . . . . . . . . 95
      nO     Computed goto  . . . . . . . . . . . . . . 96
      nP     Advance or back up n pages . . . . . . . . 59
      m,nP   Write out chars m to n . . . . . . . . . . 59
      nPW    Write buffer n times . . . . . . . . . . . 59
      m,nPW  Write out chars m to n . . . . . . . . . . 59
      Qq     Number in Q-register q . . . . . . . . . . 83, 90
      :Qq    Size of text in Q-register q . . . . . . . 83, 90
      nR     Back up n characters . . . . . . . . . . . 62
      nS     Local search . . . . . . . . . . . . . . . 71
      m,nS   Search for nth occurrence within m ch  . . 145
      ::S    Compare string . . . . . . . . . . . . . . 73

     Standard TECO                                            PAGE 218
     Index


      SEEALL "View All" characters display mode . . . . 29
      nT     Type n lines . . . . . . . . . . . . . . . 63
      m,nT   Type from m to n . . . . . . . . . . . . . 63
      nUq    Put number n into Q-register q . . . . . . 80
      nV     Type n current lines . . . . . . . . . . . 63
      m,nV   Type m before & n after current line . . . 64
      W      Scope "WATCH"  . . . . . . . . . . . . . . 113
      n:W    Return scope characteristics . . . . . . . 114, 146
      m,n:W  Set scope characteristics  . . . . . . . . 115
      nXq    Put n lines into Q-register q  . . . . . . 81
      m,nXq  Put characters m to n into Q-register  . . 81
      n:Xq   Append n lines to Q-register q . . . . . . 82
      m,n:Xq Append characters m to n into Q-regis  . . 82
      Y      Read into buffer . . . . . . . . . . . . . 59
      Z      End of buffer value  . . . . . . . . . . . 89
      [q     Q-register push  . . . . . . . . . . . . . 83
      \      Value of digit string in buffer  . . . . . 88, 90
      n\     Convert n to digits in buffer  . . . . . . 88
      ]q     Q-register pop . . . . . . . . . . . . . . 82
      n_     Global search without output . . . . . . . 72
      `      ESCape surrogate typeout . . . . . . . . . 3, 30, 39, 107, 111
      a-z    Treated the same as upper case A-Z . . . . 214
      {      Not a TECO command . . . . . . . . . . . . 214
      |      Start ELSE part of conditional . . . . . . 101
      }      Not a TECO command . . . . . . . . . . . . 214
      ~      Not a TECO command . . . . . . . . . . . . 214
      DEL    Delete last character typed in . . . . . . 39