getAudioChannelFunc typedef
        getAudioChannelFunc =
     void Function(Pointer<Void>  csound, Pointer<Utf8>  channelName, Pointer<Double>  value)
    
    
    
Implementation
typedef getAudioChannelFunc = void Function(
    Pointer<Void> csound, Pointer<Utf8> channelName, Pointer<Double> value);