From mboxrd@z Thu Jan  1 00:00:00 1970
From: Clemens Ladisch <clemens@ladisch.de>
Subject: Re: snd_pcm_wait function
Date: Sat, 10 Nov 2012 18:20:12 +0100
Message-ID: <509E8CCC.5040003@ladisch.de>
References: <509E8445.8050001@tele2.nl>
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To: Enno Fennema <ennofennema@tele2.nl>
Cc: alsa-devel@alsa-project.org
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Enno Fennema wrote:
> The documentation says this functions waits for the pcm to become ready for I/O.
> I am not sure what ready means in this context.

Ready for playback/capture, i.e., some frames are available.

> Is there a function to wait for entering the SETUP state. In particular I would
> like to wait for pcm_snd_drain to finish.

This is not possible.  alsa-lib is not thread-safe, so while another thread is
executing snd_pcm_drain, you cannot access the same PCM device.
Let the other thread send a message after snd_pcm_drain has finished.


Regards,
Clemens