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Date: Wed, 21 Jun 2006 11:58:02 +0200
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From: =?iso-8859-15?Q?Tobias_B=E4r?= <Tobias.Baer@domain.hid>
Subject: Re: [Xenomai-help] mutex locking
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> Try this, it's safe from such races:
> 
> /* returns -EWOULDBLOCK if the mutex is locked */
> if (rt_mutex_lock(&write_mutex,TM_NONBLOCK) == 0)
> {
>       // do sth.
> 
>       rt_mutex_unlock(&mutex);
> }

Thank's for the quick reply! But another question: How could it be that a mutex is locked twice?

if(rt_mutex_lock(&write_mutex,TM_NONBLOCK) == 0)
  {
    if(rt_mutex_lock(&write_mutex,TM_NONBLOCK) == 0)
      printf("Mutex is locked twice!\n");

   rt_mutex_unlock(&mutex);
  }

Is it locked by the ID of the thread?

Tobias