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From: Gernot Payer <gpayer@suse.de>
To: Chris Wright <chrisw@osdl.org>
Subject: Re: Patch to disarm timers after an exec syscall
Date: Thu, 30 Jun 2005 10:27:57 +0200
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On Wednesday 29 June 2005 20:27, Chris Wright wrote:
> No, this can't do.  It conflicts with the other bit of requirements.
> Specifically:
> http://www.opengroup.org/onlinepubs/009695399/functions/exec.html
>
> As you mention:
>
>   [TMR] Per-process timers created by the calling process
>   shall be deleted before replacing the current process image with the new
>   process image.
>
> But also:
>
>   The new process shall inherit at least the following attributes from the
>   calling process image:
>   <snip>
>   o [XSI] Interval timers
>
> And this kills the latter.

Ah, thanks for pointing that out. Unfortunately this fact isn't made clear in 
the timer_create page and the exec page isn't very understandable for 
non-native speakers and non-lawyers. ;-)

But after reading the parts you mentioned (expecially the [XSI] and [TMR] 
acronyms), I have to agree with you, the patch is wrong and so is the test 
case I mentioned.

However, poking around in the kernel was fun anyway. ;-)

> thanks,
> -chris

mfg
Gernot