MidiOutAlsa last events don't get sent, when the RtMidiOut is closed

[jpcima]

When I call sendMessage on ALSA, there is a delay before it actually gets sent.
If RtMidiOut is destroyed too soon after the sendMessage(), the message never transmits.
In a MIDI player program, I want to send final events to restore the state of the instrument after playing, but they don't happen.

Minimal test program: miditest.cc

If you run this and connect it to gmidimonitor, you may be able to reproduce the problem.

• Steps

1. Run the program, and press enter at each step when prompted.
   In the monitor, you see a NoteOn event happen, but not NoteOff.
2. Compile and run again, but uncommenting a 1 second temporization before the end.
   You should see the two events.

• Notes

The ALSA api returned 0 on snd_seq_drain_output(), which suggests the event was sent, but in reality it wasn't (yet).
A relevant API may be snd_seq_sync_output_queue() but I couldn't get anything of it in all I tried.

• Environment
  Linux quad 4.15.15-1-ARCH Fix rtmidi-config, add install/uninstall targets, support --prefix. #1 SMP PREEMPT Sat Mar 31 23:59:25 UTC 2018 x86_64 GNU/Linux
  alsa-lib 1.1.5

[chronopoulos]

i was not able to reproduce this - i see the Note Off event in both cases. using Linux 4.8.0-53-generic #56~16.04.1-Ubuntu SMP, with libasound2 version 1.1.0 and RtMidi version 3.0.0 (latest release).

what version of RtMidi are you using?

[radarsat1]

I'm afraid I also see both events in both cases.

[jpcima]

Just now I find myself unable to reproduce the bug too.
And I realize it's because I was connecting through a2j before. And it was a2j the culprit of the bug all along... Under ordinary conditions it works. So I'm closing this.