Re: [Xenomai-help] Problem with mutexes in daemon

[Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>]

Roman Pisl wrote:
> Gilles Chanteperdrix napsal(a):
>> 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.
>>
> 
> I understand, but daemon() is the first call and everything is done in 
> the new forked process.
> 
> What is the best solution for now? Is everything except unnamed mutexes 
> supposed to work well in daemon or should I cancel the concept of daemon 
> at all?

Yes, what you are doing is supposed to work, I did not look at your
code, I thought you were expecting to be able to create the mutex in a
process and use it in its child.

On what platform do you get these issues ?

-- 
                                                 Gilles.