From: Clemens Ladisch <clemens@ladisch.de>
To: John Lindgren <john.lindgren@tds.net>
Cc: alsa-devel@alsa-project.org
Subject: Re: [PATCH] alsa-lib: snd_pcm_delay and friends do not account for a write being currently in progress
Date: Thu, 03 Jun 2010 16:48:29 +0200 [thread overview]
Message-ID: <4C07C0BD.8000009@ladisch.de> (raw)
In-Reply-To: <1275573648.1415.6.camel@satellite>
John Lindgren wrote:
> On Thu, 2010-06-03 at 08:40 +0200, Clemens Ladisch wrote:
> > Alsa-lib is not thread safe.
>
> From http://alsa-project.org/main/index.php/Main_Page:
>
> ALSA has the following significant features:
> ...
> SMP and thread-safe design.
>
> So, that's a big lie?
That applies to the kernel code.
Most functions in alsa-lib must not be called at the same time on the
same device handle. (Don't ask me where this is documented.)
> > ... poll()
>
> Would it work to simply call snd_pcm_wait?
Yes. (I usually suggest poll because the code that writes audio data
often wants to be informed of some other event. If your writing loop
doesn't need to be interrupted, snd_pcm_wait works just fine.)
Regards,
Clemens
next prev parent reply other threads:[~2010-06-03 14:48 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-06-02 21:29 [PATCH] alsa-lib: snd_pcm_delay and friends do not account for a write being currently in progress John Lindgren
2010-06-03 6:40 ` Clemens Ladisch
2010-06-03 14:00 ` John Lindgren
2010-06-03 14:48 ` Clemens Ladisch [this message]
2010-06-03 16:16 ` John Lindgren
2010-06-03 17:03 ` Clemens Ladisch
2010-06-03 17:51 ` John Lindgren
2010-06-03 14:40 ` [PATCH] " James Courtier-Dutton
2010-06-03 16:10 ` John Lindgren
2010-06-03 16:34 ` James Courtier-Dutton
2010-06-03 18:06 ` John Lindgren
2010-06-03 17:40 ` VDR User
2010-06-03 18:08 ` John Lindgren
2010-06-04 6:50 ` Clemens Ladisch
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