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Date: Mon, 04 Jan 1999 17:26:37 +0000
From: "P.J.Leonard" <P.J.Leonard@bath.ac.uk>
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To: alsa-devel@alsa.jcu.cz
Subject: Re: ALSA Sequencer API
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Jaroslav Kysela wrote:
> 
> On Sun, 3 Jan 1999, Frank van de Pol wrote:
> 
> > > when I wrote the jazz midi sequencer I found it very hard to implement a
> > > working midi-thru with the OSS API (with the OUTOFBAND ioctl).
> 
> Hello Andreas,
> 
>         version 0.3.0pre1+ of driver comes with first useable version of
> sequencer. Currently this sequencer is working only with external MIDI
> devices (no wavetable or other drivers for onboard synthesizer are
> available yet), but we welcome any questions/ideas/test code for it.
>         It would be nice work on sequencer together with experienced
> application developers which should help us correct some things.
> 
>                                                         Jaroslav

 Is the ../test/seq/  code meant to compile ?

 By default the seq.h is unresolved. Using the seq.h in the lib/include
gives errors

/home/pjl/asla/alsa-driver-0.3.0-pre2/test/seq $ make -k
cc -O2 -m486 -malign-loops=2 -malign-jumps=2 -malign-functions=2
-DCPU=586 -DLI\
NUX -Wall -Wstrict-prototypes -fomit-frame-pointer -pipe
-I/usr/src/linux/inclu\
de -I../../include -I/home/pjl/asla/alsa-lib-0.3.0pre2/include -o opn2
opn2.c
In file included from opn2.c:29:
/home/pjl/asla/alsa-lib-0.3.0pre2/include/seq.h:21: parse error before
`snd_seq\
_system_info_t'

 etc.

 Also I see that user land clients sit on a file waiting for a message.
Has anyone
done any tests on the latency involved here ? This is important if I am
going to
support alsa from cantor (my sequencer). As Frank mentioned user land
clients need 
tight timing. I see that the examples run the user code as a real-time
task.
What if the user client hangs (CTRL-ALT-DELETE ?)

  cheers Paul.

