Function soundio::instream_read_callback

pub extern "C" fn instream_read_callback(
    stream: *mut SoundIoInStream, 
    frame_count_min: c_int, 
    frame_count_max: c_int
)

This is called when an instream has been read. The InStreamUserData struct is obtained from the stream.userdata, then the user-supplied callback is called with an InStreamReader object.