Re: [Alsa-user] alsa-only applications (such as jitsi) via jackd

[Peter P. <pet...@fa...>]

* Peter P. <pet...@fa...> [2020-04-21 20:20]:
> * Clemens Ladisch via Alsa-user <als...@li...> [2020-04-12 11:55]:
> > Peter P. wrote:
> > > Can I set pcm device names per application as defaults?
> > 
> > If the application does not allow you to set the ALSA device name,
> > you have to replace the device definition that the application used
> > (probably "default").
> Thanks Clemens, just to make sure I get you right: Some applications do
> not allow me to set "PCM devices" but only cards? In that case I can
> only redefine default by changing/creating a .asoundrc?
>  
> > It would be possible to create a device definition that reads an
> > environment variable (the "hw" device does this with ALSA_PCM_*),
> > but the "default" device does not do this.
> I am just making my way through alsa terminology, let me ask you if you
> mean a "PCM device" called hw, not the hw as a protocol for accessing
> cards? 

I am replying to my last thread here to tell that I finally managed to
make a non-jackified application (jitsi meet application image in my
case) use jack. I did this by installing the libasound2-plugins Debian
package, which provides a jack plugin for alsa. Then I created an
.asoundrc with the below contents which points to the built-in soundcard
hw:0 as a default, but permits any environment variable (ALSAPP for me)
to change this assignment

	pcm.!default{
		type plug
		slave.pcm { 
			@func getenv
			vars [ ALSAPP ]
			default "hw:0" 
		}
	}

With jackd running I can now start any application prefixed with that
variable pointing to the jack plugin
 $ ALSAPP=jack ffmuc-meet-x86_64.AppImage

If anyone sees something I could improve here I'd be glad to know.
Thanks for the help on this list!

cheers, P