fix(coremidi): run CFRunLoop on dedicated OS thread for hot-plug notifications#3
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…fications CoreMIDI delivers MIDIClientCreate notifications on the CFRunLoop of the thread that created the client. Go goroutines have no CFRunLoop by default, so hot-plug events were registered but never delivered. Fix NewClient to: - Lock the goroutine to a dedicated OS thread (runtime.LockOSThread) - Capture CFRunLoopGetCurrent() on that thread - Block the thread on runMIDIRunLoop() for the client lifetime - Stop the run loop in Dispose() via CFRunLoopStop Also remove m.client.Dispose() from Stop() so the notification run loop survives stop/start capture cycles. Add Close() for full teardown.
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Problem
CoreMIDI delivers
MIDIClientCreatenotifications on the CFRunLoop of the thread that created the client. Go goroutines do not have a CFRunLoop by default — so hot-plug events (device connect/disconnect) were registered but never actually delivered.Additionally,
Stop()was callingclient.Dispose(), which destroyed the notification channel entirely. This meantWatchDeviceswould go permanently blind after the first stop/start cycle.Fix
internal/coremidi/client.goNewClientnow spawns a goroutine locked to a dedicated OS thread (runtime.LockOSThread)CFRunLoopGetCurrent()on that threadrunMIDIRunLoop()(usesCFRunLoopRunInModeloop, exits cleanly onkCFRunLoopRunStopped)Dispose()callsCFRunLoopStopbefore deleting the cgo handleinternal/midi/mididarwin/client_darwin.gom.client.Dispose()fromStop()— the run loop and notification channel must survive between capture sessionsClose()for full teardown (callsStop()+Dispose())