semi OT input callback question
Semi off topic question here. I hope you fine folks won't mind terribly if I ask a general AudioUnit question as I'm not having much luck finding the answer elsewhere and am hoping someone here might know.
Both input and render callbacks one sets on a remoteIO unit have the same function signature. In the case of an input callback, the final AudioBufferList parameter (e.g. ioData in many sample projects and docs) is NULL and appears to serve no purpose at all.
Does that parameter ever serve a purpose beyond matching the AURenderCallback function signature?