From mboxrd@z Thu Jan  1 00:00:00 1970
From: Clemens Ladisch <clemens@ladisch.de>
Subject: Re: Question about dmix?
Date: Mon, 22 Mar 2010 09:03:48 +0100
Message-ID: <4BA72464.3050900@ladisch.de>
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To: cee1 <fykcee1@gmail.com>
Cc: alsa-devel@alsa-project.org
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cee1 wrote:
> I know alsa support userspace software multi-playback by dmix plugin.
> How does it realize? I expected a daemon accepting multi-streams which
> then mixes these streams to a single one -- it seems not the case.

The kernel maps the device's DMA buffer into all userspace processes;
the processes then cooperate in adding samples to the buffer.


Regards,
Clemens