Loopback device conf/alias

Loopback device conf/alias

[pl bossart]

I played with the snd_aloop module that Jaroslav added a couple of
days ago. It just does what I wanted and seems to work ok :-) Thanks
for this patch!

I would like however to expose this output as a PulseAudio profile.
Using a string such as hw:%f conflicts with other analog output
profiles, and the actual card index will vary depending on each
hardware setup.
Is there a way to have an alias or a configuration so that I could use
a profile definition as aloop:%f in PulseAudio, and use arecord
-Daloop for my monitoring app. By default the playback device would be
0 and the capture one 1. As long as the card index is handle
automatically I am happy.

I tried to play with alsa-lib .conf files, no luck (I really have no
idea how this works). Any ideas on how to add an alias?
Thanks for your feedback
-Pierre

Re: Loopback device conf/alias

[Jaroslav Kysela]

On Tue, 24 Aug 2010, pl bossart wrote:

> I played with the snd_aloop module that Jaroslav added a couple of
> days ago. It just does what I wanted and seems to work ok :-) Thanks
> for this patch!
>
> I would like however to expose this output as a PulseAudio profile.
> Using a string such as hw:%f conflicts with other analog output

Use 'hw:Loopback' device or assign any other car ID string as the module 
parameters (id=<your_string>) or you may change the card ID string at
runtime using 'echo <your_string> > /sys/class/sound/card1/id', replace 
card1 with the loopback card index (this way may be used in udev scripts 
where you can check the module name (snd_aloop) as well).

 						Jaroslav

-----
Jaroslav Kysela <perex@perex.cz>
Linux Kernel Sound Maintainer
ALSA Project, Red Hat, Inc.

Re: Loopback device conf/alias

[pl bossart]

> Use 'hw:Loopback' device or assign any other car ID string as the module
> parameters (id=<your_string>) or you may change the card ID string at
> runtime using 'echo <your_string> > /sys/class/sound/card1/id', replace
> card1 with the loopback card index (this way may be used in udev scripts
> where you can check the module name (snd_aloop) as well).

Works fine. Thanks for the tip.
-Pierre