diff --git a/RELEASE_NOTES.md b/RELEASE_NOTES.md
index 9f518f6cf2..cb7e50b583 100644
--- a/RELEASE_NOTES.md
+++ b/RELEASE_NOTES.md
@@ -6,6 +6,8 @@
   functions.
 * New build mode `:bytecode-faso` which builds the kernel as native
   code (FASO) while the bytecode compiler is active.
+* Generic `gray:stream-file-length` which implements `cl:file-length`
+  for Gray streams.
 
 ## Removed
 * Obsolete `:object`, `:ll`, `:bc`, and `:fasl` build modes.
diff --git a/src/core/grayPackage.cc b/src/core/grayPackage.cc
index 577679fb6c..15552206a6 100644
--- a/src/core/grayPackage.cc
+++ b/src/core/grayPackage.cc
@@ -54,7 +54,6 @@ SYMBOL_EXPORT_SC_(GrayPkg, stream_write_sequence);
 SYMBOL_EXPORT_SC_(GrayPkg, stream_unread_char);
 SYMBOL_EXPORT_SC_(GrayPkg, stream_peek_char);
 SYMBOL_EXPORT_SC_(GrayPkg, stream_listen);
-SYMBOL_EXPORT_SC_(GrayPkg, streamClearInput);
 SYMBOL_EXPORT_SC_(GrayPkg, stream_clear_input);
 SYMBOL_EXPORT_SC_(GrayPkg, stream_clear_output);
 SYMBOL_EXPORT_SC_(GrayPkg, stream_force_output);
@@ -64,7 +63,7 @@ SYMBOL_SHADOW_EXPORT_SC_(GrayPkg, input_stream_p);
 SYMBOL_SHADOW_EXPORT_SC_(GrayPkg, output_stream_p);
 SYMBOL_EXPORT_SC_(GrayPkg, stream_interactive_p);
 SYMBOL_SHADOW_EXPORT_SC_(GrayPkg, stream_element_type);
-SYMBOL_EXPORT_SC_(GrayPkg, stream_file_position);
+SYMBOL_EXPORT_SC_(GrayPkg, stream_file_length);
 SYMBOL_EXPORT_SC_(GrayPkg, stream_file_position);
 SYMBOL_EXPORT_SC_(GrayPkg, stream_line_column);
 SYMBOL_EXPORT_SC_(GrayPkg, stream_line_length);
diff --git a/src/core/lispStream.cc b/src/core/lispStream.cc
index aa84709c3c..8f6b020987 100644
--- a/src/core/lispStream.cc
+++ b/src/core/lispStream.cc
@@ -1459,7 +1459,7 @@ static int clos_stream_interactive_p(T_sp strm) { return !T_sp(eval::funcall(gra
 
 static T_sp clos_stream_element_type(T_sp strm) { return eval::funcall(gray::_sym_stream_element_type, strm); }
 
-#define clos_stream_length not_a_file_stream
+static T_sp clos_stream_length(T_sp strm) { return eval::funcall(gray::_sym_stream_file_length, strm); }
 
 static T_sp clos_stream_get_position(T_sp strm) { return eval::funcall(gray::_sym_stream_file_position, strm); }
 
diff --git a/src/lisp/kernel/clos/streams.lisp b/src/lisp/kernel/clos/streams.lisp
index 6026f5f3f4..7b3296d79a 100644
--- a/src/lisp/kernel/clos/streams.lisp
+++ b/src/lisp/kernel/clos/streams.lisp
@@ -205,6 +205,10 @@
   (:documentation
    "This is like CL:FILE-POSITION, but for Gray streams."))
 
+(defgeneric stream-file-length (stream)
+  (:documentation
+   "This is like CL:FILE-LENGTH, but for Gray streams."))
+
 (defgeneric stream-file-descriptor (stream &optional direction)
   (:documentation
    "Return the file-descriptor underlaying STREAM, or NIL if not
@@ -621,6 +625,14 @@
   (declare (ignore stream position))
   nil)
 
+;; FILE-LENGTH
+
+(defmethod stream-file-length ((stream ansi-stream))
+  (file-length stream))
+
+(defmethod stream-file-length ((stream t))
+  (error 'type-error :datum stream :expected-type 'file-stream))
+
 ;; STREAM-P
 
 (defmethod streamp ((stream stream))