MIDINotifyProc

typedef void (*MIDINotifyProc)(const MIDINotification *message, void *refCon);

This callback function is called when some aspect of the current MIDI setup changes. Currently the only defined message is kMIDIMsgSetupChanged, which simply means, "something changed." msgData is null in this case. It is called on the runloop (thread) on which MIDIClientCreate was first called.

Parameters

Name	Description
message	A structure containing information about what changed.
refCon	The client's refCon passed to MIDIClientCreate.