diff --git a/eio/tar_eio.ml b/eio/tar_eio.ml
index 60d6c68..597155d 100644
--- a/eio/tar_eio.ml
+++ b/eio/tar_eio.ml
@@ -56,7 +56,7 @@ let run t f =
       let buffer_size = 32768 in
       let buffer = Cstruct.create buffer_size in
       let rec loop (n: int) =
-        if n <= 0 then Ok (-1) (* XXX: I dunno... *)
+        if n <= 0 then Ok ()
         else
           let amount = min n buffer_size in
           let block = Cstruct.sub buffer 0 amount in
diff --git a/unix/tar_unix.ml b/unix/tar_unix.ml
index b64dac0..2f4c0cd 100644
--- a/unix/tar_unix.ml
+++ b/unix/tar_unix.ml
@@ -46,7 +46,6 @@ type decode_error = [
   | `Fatal of Tar.error
   | `Unix of Unix.error * string * string
   | `Unexpected_end_of_file
-  | `Msg of string
 ]
 
 let pp_decode_error ppf = function
diff --git a/unix/tar_unix.mli b/unix/tar_unix.mli
index eda3e75..122d532 100644
--- a/unix/tar_unix.mli
+++ b/unix/tar_unix.mli
@@ -44,7 +44,7 @@ val fold :
 val extract :
   ?filter:(Tar.Header.t -> bool) ->
   src:string -> string ->
-  (unit, [> `Exn of exn | decode_error ]) result
+  (unit, [> `Exn of exn | `Msg of string | decode_error ]) result
 
 (** [create ~level ~filter ~src dst] creates a tar archive at [dst]. It uses
     [src], a directory name, as input. If [filter] is provided