bug#16686: 23.1; hexl-insert-hex-char shortens file by 7 bytes

[Eli Zaretskii]

> Date: Fri, 7 Feb 2014 17:42:45 -0800
> From: Jacob Burckhardt <jburckhardt@pdvcorp.com>
> 
> hexl-insert-hex-char is supposed to change a character meaning the file
> size should remain the same.  But it actually deletes 7 bytes from the
> file.  Here is how to reproduce it:
> 
> * In the shell, I ran: env printf
> '\xee\x00\x4a\x7b\x30\x90\x00\x40\x00\x00\x00\x00\x00\x00\x00\x00\x00\x0
> 0\x00\x00\x00\x00\x00' >! /tmp/testfile
> 
> * In the shell, I ran "env ls -l /tmp/testfile".  It output:
> 
> -rw-r--r-- 1 jburckhardt jburckhardt 23 Feb  7 17:27 /tmp/testfile
> 
> * emacs -q /tmp/testfile &
> 
> * M-x hexl-mode <return>
> 
> * M-x hexl-insert-hex-char <return>
> 
> * ff <return>
> 
> * C-x C-s
> 
> * Type 'y' to acknowledge the warning about loss of undo info.
> 
> * In the shell, I ran "env ls -l /tmp/testfile".  It output:
> 
> -rw-r--r-- 1 jburckhardt jburckhardt 16 Feb  7 17:29 /tmp/testfile
> 
> Notice that the first ls command said 23 bytes, but the last ls command
> said 16 bytes.  So it lost 7 bytes.  The second ls command should have
> also said 23 bytes.
> 
> This happened on GNU Emacs 23.1.1 on a machine whose "uname -a" says:
> 
> Linux bb003-centos-02 2.6.32-358.14.1.el6.x86_64 #1 SMP Tue Jul 16
> 23:51:20 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux

Thanks for the report.  I cannot reproduce this problem with Emacs 24,
so I guess this bug was already fixed.