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Date: Sun, 08 Feb 2015 22:29:33 +0100
From: Hans Petter Selasky <hps@selasky.org>
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Subject: Re: Sound reasoning
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On 02/08/15 22:22, Евгений Б. Спамаковский wrote:
> Hi.
>
> Is there a point to writing a pcm device to have multiple "channel"s in the
> same direction?
> Say, two SND_FORMAT(AFMT_S16_LE, 1, 0) for record and two for playback, vs.
> just one SND_FORMAT(AFMT_S16_LE, 2, 0) in each direction.
>
> pcm_register() has so prominently two arguments 'numrec' and 'numplay' and
> even if they are ignored, one can do pcm_addchan() any number of times.
> How is this expressed to the user-land programmer?
>
> "Read the code" is a fine answer, but it would be nice if someone can
> readily explain the idea behind the options.

Hi,

Sounds similar to what my "virtual_oss" is doing. See:

svn --username anonsvn --password anonsvn \
       checkout svn://svn.turbocat.net/i4b/trunk/ports

--HPS