When called by the system, provides beat and tempo information to an audio unit from a host application.
- iOS 10.0+
- macOS 10.12+
- Mac Catalyst 13.0+
- tvOS 10.0+
Custom data that you provided when registering your callback with the audio unit.
On output, the current beat of the music that is playing.
On output, the current tempo of the music that is playing.
If you named your callback function
My, you would declare it like this: