From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mike Gorse <mgorse@mgorse.dhs.org>
Subject: interrupting snd_pcm_writei or snd_pcm_drain?
Date: Wed, 14 Nov 2007 12:34:07 -0400 (GMT+4)
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I've noticed that it is unsafe to call snd_pcm_writei or snd_pcm_drain in 
a pthread with its cancelation type set to asynchronous. 
snd_pcm_dmix_sync_area can lower a semaphore, and, if the thread is 
canceled while the semaphore is down, then a subsequent call to the sound 
device (calling snd_pcm_close, for instance) will also lower the semaphore 
and cause deadlock.  Is this a known issue, and is there a way around it 
other than to always use deferred cancelation when calling these 
functions?

Thanks,
-Mike G-