From mboxrd@z Thu Jan  1 00:00:00 1970
From: Clemens Ladisch <clemens@ladisch.de>
Subject: Re: cloning snd_seq_t (or creating one from client id)
Date: Mon, 31 Mar 2014 14:29:27 +0200
Message-ID: <53395FA7.5050704@ladisch.de>
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To: Tobias Schlemmer <keinstein_junior@gmx.net>, alsa-devel@alsa-project.org
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Tobias Schlemmer wrote:
> I'm surprised that the upcoming version of RtMidi uses one ALSA client
> per MIDI port.
>
> I found out that sequencer handles (snd_seq_t) are not thread safe.

A sequencer client use a common buffer for the events of all ports.

> Could you provide some way to implement multithreaded ALSA clients?

Multiple threads would have to synchronize the buffer accesses in some
way.  How exactly merging and distributing of events from/to multiple
ports is handled (even when some thread does not react) is a policy that
cannot be imposed by the ALSA library.


Regards,
Clemens