Colin, thanks for the suggestion. I tried building and running from the current git HEAD version and still had the same problem. I also noticed that my app has been causing a core dump due to an infinite recursion in snd_config_searcha_hooks. I'm not sure what would cause both of these problems. I'm trying going back to stock packages on my system (Ubuntu 9.04) to see if a version incompatibility.

Gavin Stark

On Sep 20, 2010, at 1:41 PM, alsa-devel-request@alsa-project.org wrote:

Date: Mon, 20 Sep 2010 16:22:02 +0100 From: Colin Guthrie gmane@colin.guthr.ie Subject: Re: [alsa-devel] Spurious "Unable to find definition 'defaults.pcm.dmix.device'" To: alsa-devel@alsa-project.org Message-ID: i77u6q$2ma$1@dough.gmane.org Content-Type: text/plain; charset=UTF-8

'Twas brillig, and Gavin Stark at 20/09/10 16:05 did gyre and gimble:

...

I am using ALSA in a gstreamer project. When playing many videos (with audio) in the same application and the same gstreamer instance every once in a while (maybe once every 500 times) I will receive the following errors (in a call chain that passes through snd_pcm_open)

confmisc.c:1286:snd_func_refer: alsalib error: Unable to find definition 'defaults.pcm.dmix.device' alsa conf.c:4154:_snd_config_evaluate: alsalib error: function snd_func_refer returned error: No such file or directory alsa conf.c:4633:snd_config_expand: alsalib error: Evaluate error: No such file or directory alsa pcm.c:2211:snd_pcm_open_noupdate: alsalib error: Unknown PCM default

The next playback will be fine. Looking through the ALSA code it seems that the configuration data should be cached and re-used unless the number of config files changes, or the files themselves change (name, device, inode. mtime) So I am wonder why on one instance of snd_pcm_open I'd end up with this error but not on most previous or subsequent calls.

All the ALSA configuration files are the defaults, I have no ~/.asoundrc, and I'm running version 1.0.23

I guess there is an outside chance that this could be some threading race condition in the config stuff.

Jaroslav recently fixed some threading issues in libalsa2 and config stuff. Perhaps it's worth pulling across those changes to your alsa lib to see if this is related?

Can't remember the git commit #'s off hand, but git master of libalsa2 is probably fine.

Long shot maybe but an relatively easy one to test.

Col

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Colin Guthrie gmane(at)colin.guthr.ie http://colin.guthr.ie/

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