Allow floating-point file offsets.

Problem reported by Vitalie Spinu in
<http://lists.gnu.org/archive/html/emacs-devel/2013-01/msg00411.html>.
* doc/lispref/files.texi (Reading from Files, Writing to Files):
Say that file offsets can be numbers, not just integers.
* src/fileio.c (emacs_lseek): Remove.
(file_offset): New function.
(Finsert_file_contents, Fwrite_region): Use it.

2 files changed, 11 insertions, 5 deletions

diff --git a/doc/lispref/ChangeLog b/doc/lispref/ChangeLog
index 2631bdf708a..851f727621e 100644
--- a/doc/lispref/ChangeLog
+++ b/doc/lispref/ChangeLog
@@ -1,3 +1,9 @@
+2013-01-19  Paul Eggert  <eggert@cs.ucla.edu>
+
+        Allow floating-point file offsets.
+        * files.texi (Reading from Files, Writing to Files):
+        Say that file offsets can be numbers, not just integers.
+
 2013-01-09  Glenn Morris  <rgm@gnu.org>
 
         * commands.texi (Interactive Codes):
diff --git a/doc/lispref/files.texi b/doc/lispref/files.texi
index 114eb1f38ea..be44590f2ec 100644
--- a/doc/lispref/files.texi
+++ b/doc/lispref/files.texi
@@ -533,9 +533,9 @@ is visiting the file @var{filename}: these include the buffer's visited
 file name and its last save file modtime.  This feature is used by
 @code{find-file-noselect} and you probably should not use it yourself.
 
-If @var{beg} and @var{end} are non-@code{nil}, they should be integers
-specifying the portion of the file to insert.  In this case, @var{visit}
-must be @code{nil}.  For example,
+If @var{beg} and @var{end} are non-@code{nil}, they should be numbers
+that are byte offsets specifying the portion of the file to insert.
+In this case, @var{visit} must be @code{nil}.  For example,
 
 @example
 (insert-file-contents filename nil 0 500)
@@ -605,8 +605,8 @@ that string, rather than text from the buffer.  @var{end} is ignored in
 this case.
 
 If @var{append} is non-@code{nil}, then the specified text is appended
-to the existing file contents (if any).  If @var{append} is an
-integer, @code{write-region} seeks to that byte offset from the start
+to the existing file contents (if any).  If @var{append} is a
+number, @code{write-region} seeks to that byte offset from the start
 of the file and writes the data from there.
 
 If @var{mustbenew} is non-@code{nil}, then @code{write-region} asks