Hi Giulio,

no, AFAICT that's not the way ALSA works. I haven't really looked in the ALSA code, but it seems that assembling the MIDI messages has to be done using the corresponding sequencer API calls. There might be some drivers which handle this, but I never had this working properly when outputting sysex using either internal ALSA connections or external MIDI gear via a USB-MIDI device.

All I can say is that the suggested patch seems to be the right way to do this (those API calls are there for a reason), and that it works for me with every MIDI equipment I tried it with.

Albert

On Sun, Oct 16, 2016 at 7:25 PM, Giulio Moro via Pd-dev <pd-dev@lists.iem.at> wrote:
Out of curiosity, is it not up to the receiving device to parse the received bytes in such a way that they form a coherent message? Or is there a "timeout" after which a sysex message is considered aborted ?
I don't remember the latter from the specs, so I always assumed the former.
Giulio


From: Albert Graef <agraef@users.sf.net>
To: pd-dev@lists.iem.at
Sent: Sunday, 16 October 2016, 18:17
Subject: [PD-dev] [pure-data:bugs] #1272 midiout not working correctly on ALSA

[bugs:#1272] midiout not working correctly on ALSA
Status: open
Group: v0.47
Created: Sun Oct 16, 2016 05:17 PM UTC by Albert Graef
Last Updated: Sun Oct 16, 2016 05:17 PM UTC
Owner: Miller Puckette
This has been there forever, and affects all Linux systems when using ALSA MIDI devices.
sys_alsa_putmidibyte() in s_midi_alsa.c outputs individual bytes instead of complete MIDI messages. You can clearly see this, e.g., when sending a sysex message from Pd to an ALSA MIDI output and looking at the results in kmidimon. Instead of a proper sysex message you'll get a sequence of (malformed) single-byte messages.
You can't just output single bytes of a multi-byte MIDI message with snd_seq_event_output_direct(), this only works with single-byte (such as system realtime) messages. The proper way to do this, so that it works with any MIDI message, is to use snd_midi_event_encode_byte() and output the message when it's complete. The following fix is from the pd-l2ork repo, but it should apply cleanly on the current pure-data master branch:
https://github.com/pd-l2ork/pd/commit/9f5a265
To unsubscribe from further messages, a project admin can change settings at https://sourceforge.net/p/pure-data/admin/bugs/options. Or, if this is a mailing list, you can unsubscribe from the mailing list.

_______________________________________________
Pd-dev mailing list
Pd-dev@lists.iem.at
https://lists.puredata.info/listinfo/pd-dev



_______________________________________________
Pd-dev mailing list
Pd-dev@lists.iem.at
https://lists.puredata.info/listinfo/pd-dev




--
Dr. Albert Gr"af
Computer Music Research Group, JGU Mainz, Germany
Email:  aggraef@gmail.com
WWW:    https://plus.google.com/+AlbertGraef