Re: [bug-diffutils] Funny behaviour of diff 2.8.1

[Philipp Thomas]

* Paul Eggert (address@hidden) [20100812 01:26]:
> On 08/11/10 14:34, Philipp Thomas wrote:
> > I got the following question from our ksh maintainer
> > (https://bugzilla.novell.com/show_bug.cgi?id=627524)
> 
> I can't read that; it's behind some sort of registration wall.

I forgot, sorry to have mentioned it.
 
> Your email doesn't mention ksh or diff version numbers, or platform,
> which makes things a bit hard to diagnose, but I'll give it a try
> anyhow.

As I wrote in the subject diff is 2.8.1. ksh is at 93t 2010-03-09 and
platform is SUSE LINUX Enterprise 11 SP1.

> Nor do I.  Nor can I reproduce the problem on my system (RHEL 5, ksh
> 93t+ 2010-02-02, diff 2.8.1).

I asked my collegue to do a ltrace and that identified the culprit. diff
(and cmp) do a reopen if input or output isn't a terminal. The solution is
to stat the file first and then add  a test for ! S_ISSOCK before reopening.
The patch I came up with is attached.

Philipp

diffutils-no_freopen_on_socket.patch
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