From mboxrd@z Thu Jan 1 00:00:00 1970 From: Takashi Iwai Subject: Re: General Guidelines? (MIDI) Date: Thu, 16 Jan 2003 19:14:14 +0100 Sender: alsa-devel-admin@lists.sourceforge.net Message-ID: References: <20030116134157.GA31876@bhv1.adelphia.net> Mime-Version: 1.0 (generated by SEMI 1.14.4 - "Hosorogi") Content-Type: text/plain; charset=US-ASCII Return-path: In-Reply-To: Errors-To: alsa-devel-admin@lists.sourceforge.net List-Help: List-Post: List-Subscribe: , List-Unsubscribe: , List-Archive: To: Tim Goetze Cc: Brian Victor , alsa-devel@lists.sourceforge.net List-Id: alsa-devel@alsa-project.org At Thu, 16 Jan 2003 16:32:05 +0100 (CET), Tim Goetze wrote: > > Brian Victor wrote: > > >On Thu, Jan 16, 2003 at 08:39:23AM +0100, Clemens Ladisch wrote: > >>Brian Victor wrote: > >>> Monitoring /proc/asound/seq/queues shows the events being queued, but as > >>> soon as the queue starts, all 400 notes leave the queue instantly; none > >>> are played. > > afaik, you should use snd_seq_event_output() instead of > snd_seq_event_output_direct() -- the latter is supposed > to by-pass the queue for instant transmission. well, this is not exact: snd_seq_event_output_direct() sends the event without "output buffer" on the user-space. if the event record has a proper queue value (i.e. event.queue != SND_SEQ_QUEUE_DIRECT), it is scheduled on the specified queue. for by-passing the scheduling on the queue, you need to mark the queue via snd_seq_ev_set_direct(). snd_seq_event_output() will put the event onto the output buffer. the buffered events won't be sent and stay on the buffer until either the buffer becomes full or snd_seq_drain_output() is called explicitly. this i/o-buffer was introduced to reduce the amounts of read/write, ioctls. this could be implemented more sofisticatedly as a high-level library... Takashi ------------------------------------------------------- This SF.NET email is sponsored by: Thawte.com Understand how to protect your customers personal information by implementing SSL on your Apache Web Server. Click here to get our FREE Thawte Apache Guide: http://ads.sourceforge.net/cgi-bin/redirect.pl?thaw0029en