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Date: Wed, 22 Apr 2009 11:57:05 +0200
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
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Subject: Re: [Xenomai-help] Problem with mutexes in daemon
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To: Roman Pisl <rpisl@domain.hid>
Cc: xenomai@xenomai.org

Roman Pisl wrote:
> Hello,
> I'm experiencing weird behavior with mutexes in a daemon application. 
> After daemon() is called, unnamed mutexes fail on call 
> rt_mutex_release() with -EPERM. Everything is ok for named mutexes.
> 
> Is there something special with daemon and unnamed mutexes - should all 
> have name? Or is it a bug? I'm using kernel 2.6.28 and Xenomai 2.4.6.1.
> 
> Example showing this problem is attached.

Unnamed mutexes are local to a process. Since forking results in a
different process, mutexes are not preserved.

Yes, Xenomai behaviour is not intuitive, but fixing this requires
internal changes.

-- 
                                                 Gilles.