GNU bug report logs - #13535
timeout command not working when SIGALRM blocked

Previous Next

To add a comment to this bug, you must first unarchive it, by sending
a message to control AT debbugs.gnu.org, with unarchive 13535 in the body.
You can then email your comments to 13535 AT debbugs.gnu.org in the normal way.

Toggle the display of automated, internal messages from the tracker.

Message #5 received at submit <at> debbugs.gnu.org (full text, mbox):

From: Stephan Krempel <krempel <at> par-tec.com>
To: bug-coreutils <at> gnu.org
Subject: timeout command not working when SIGALRM blocked
Date: Wed, 23 Jan 2013 18:44:49 +0100

[Message part 1 (text/plain, inline)]

Hi there,

If the calling process has SIGALRM blocked, timeout simply never times out.

Find attached a small program to demonstrate the problem and a patch to
fix it by unblocking the necessary signal (at least on x86/linux).

If this is intended behavior, I would suggest to document it explicitly
to prevent people from tapping into the same pitfall that I hit.

Greetings
Stephan

[blocksigalrm.pl (application/x-perl, attachment)]

[unblock_sigalrm.patch (text/x-patch, attachment)]

[signature.asc (application/pgp-signature, attachment)]

Message #10 received at 13535-done <at> debbugs.gnu.org (full text, mbox):

From: Pádraig Brady <P <at> draigBrady.com>
To: Stephan Krempel <krempel <at> par-tec.com>
Cc: 13535-done <at> debbugs.gnu.org
Subject: Re: bug#13535: timeout command not working when SIGALRM blocked
Date: Fri, 25 Jan 2013 03:12:24 +0000

[Message part 1 (text/plain, inline)]

On 01/23/2013 05:44 PM, Stephan Krempel wrote:
> Hi there,
>
> If the calling process has SIGALRM blocked, timeout simply never times out.
>
> Find attached a small program to demonstrate the problem and a patch to
> fix it by unblocking the necessary signal (at least on x86/linux).

The sigprocmask gnulib module is used if the sigaction
module is needed, so we should be able to use sigprocmask
unconditionally here. There is even an implementation
for windows included if needed.

> If this is intended behavior, I would suggest to document it explicitly
> to prevent people from tapping into the same pitfall that I hit.

I agree with your patch, and have attached an updated version.

Hmm I suppose we should also do this for SIGCHLD as a follow on from:
http://git.sv.gnu.org/gitweb/?p=coreutils.git;a=commitdiff;h=73d46261

thanks,
Pádraig.

[timeout-block-alrm.patch (text/x-patch, attachment)]

Message #13 received at 13535 <at> debbugs.gnu.org (full text, mbox):

From: Bernhard Voelker <mail <at> bernhard-voelker.de>
To: 13535 <at> debbugs.gnu.org, P <at> draigBrady.com, krempel <at> par-tec.com
Subject: Re: bug#13535: timeout command not working when SIGALRM blocked
Date: Fri, 25 Jan 2013 08:43:45 +0100

On 01/25/2013 04:12 AM, Pádraig Brady wrote:
> I agree with your patch, and have attached an updated version.

+1 if you mention http://bugs.gnu.org/13535.

Have a nice day,
Berny

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.