How to know when MIDI file has finished with OS X MusicPlayer - macos

Question

I want to be able to play MIDI files that are included as resources in my app. I have a very simple function to do this, given the name of the resource (minus the .MID) file extension:
MusicPlayer musicPlayer;
MusicSequence sequence;
int MusicPlaying=0;
void PlayMusic(char *fname)
{
OSStatus res=noErr;
res = NewMusicPlayer(&musicPlayer);
res = NewMusicSequence(&sequence);
strcpy(TmpPath, "MUSIC/");
strcat(TmpPath, fname);
strcat(TmpPath, ".MID");
NSString *iName = [NSString stringWithUTF8String:TmpPath];
NSURL *url = [[NSBundle mainBundle] URLForResource:iName withExtension:nil];
res = MusicSequenceFileLoad (sequence, (__bridge CFURLRef _Nonnull)(url), 0, kMusicSequenceLoadSMF_ChannelsToTracks);
res = MusicPlayerSetSequence(musicPlayer, sequence);
res = MusicPlayerStart(musicPlayer);
if( res==noErr ) MusicPlaying = 1;
}
This all works fine and dandy, takes very little code... the problem is that I can't figure out how to know when the MIDI file has finished playing. I've tried MusicPlayerIsPlaying() (it ALWAYS returns true, LONG after the file has finished). I've tried checking MusicPlayerGetTime(), but the time count keeps on going after the MIDI finishes. I can't find any way to get a notification from this or any other way to determine that the actual MIDI data has finished playing.
Any ideas?

Answer 1

Apple's PlaySequence example shows how to do this:
You have to determine the length of the sequence by getting the length of each track:
MusicSequenceGetTrackCount(sequence, &ntracks);
for (UInt32 i = 0; i < ntracks; ++i) {
result = MusicSequenceGetIndTrack(sequence, i, &track);
result = MusicTrackGetProperty(track, kSequenceTrackProperty_TrackLength,
&trackLength, &propsize);
if (trackLength > sequenceLength)
sequenceLength = trackLength;
}
Then wait until you have reached that time:
while (1) {
usleep (2 * 1000 * 1000);
result = MusicPlayerGetTime(player, &time);
if (time >= sequenceLength)
break;
}