Currently (version 1.0.29) it attempts to open it, and produces this somewhat misleading message:
> ALSA lib seq_hw.c:457:(snd_seq_hw_open) open /dev/snd/seq failed: No such file or directory
Instead, it should return an error right away, and the message should say that ALSA sequencer isn't available on FreeBSD.
Can you provide an example command line or a piece of code? seq interface isn't implemented by any plugin among alsa-plugins. And snd_seq_open() already returns an error (-2) if a device cannot be opened, see test/playmidi1.c.
oss plugin can probably leverage libsalsa code but needs to support software synthesizer when there's no hardware (no virmidi to redirect). Patches welcome...
I got this error message during an attempt to port one Linux audio package. It bounded to libasound.so.2 and the message got produced. (The package itself might be ALSA-only, and is probably not able to work on FreeBSD, although it is a very nice tool.)
If you would really like to reproduce it, I am attaching the shar for the port that I was trying to make: qtractor. It builds, and runs when Jack audio server is running (/usr/local/bin/jackd -R -doss -r44100 -p1024 -n3 -w16 -C/dev/dsp0 -P/dev/dsp0).
It prints the above message.
Also here is the DTrace log of the failure operation:
0 61925 openat:return openat failure: fd=-100 file=/dev/snd/seq flags=1048582 errno=2
qtractor`QWindowsStyle::drawControl(QStyle::ControlElement, QStyleOption const*, QPainter*, QWidget const*) const+0x3483
qtractor`QWindowsStyle::drawControl(QStyle::ControlElement, QStyleOption const*, QPainter*, QWidget const*) const+0x1e3
Created attachment 162213 [details]
Unfinished qudio/qtractor port as a testcase
Is this still relevant?
I will retest it and will see if this is still relevant.
There is now audio/alsa-seq-server in base.
And it should work with ALSA's /dev/snd/seq .