[alsa-devel] /usr/share/alsa/alsa.conf :and file extention

Rene Herman rene.herman at keyaccess.nl
Mon Mar 17 04:18:15 CET 2008

On 17-03-08 03:57, Alexander Indenbaum wrote:

> I'm playing with embedded system without any hardware sound device. I'd like
> to grab sound from ALSA application, for instance Firefox displaying YouTube
> clip inside flash plugin and to store  output PCM stream into file on local
> disk. I got an advice to use File extension. So I defined following
> /usr/share/alsa/alsa.conf

Don't do it there. Use /etc/asound.conf or $HOME/.asoundrc ...

> pcm.default{
>         type
> file
>         file
> /tmp/pcm.out
> }

... and make it

pcm.!default {
         type    file
         slave   {
                 pcm     null
         file    "/tmp/pcm.out"

Exactly why you need that slave definition I'm not sure either, but it seems 
you do. Also note that /tmp/pcm.out will be headerless PCM and is recreated 
for individual opens. I don't believe there's an append mode or anything 
(and you'd need to make sure that everyone plays the same format) so not 
toot sure if this is what you need to have a catch all audio-sink...


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