anchor.diff:    }
   
     /// Write bytes
  -  Future<bool> write(List<int> bytes){
  +  Future write(List<int> bytes){
       final writes = bytes.map((byte) => _writeOneByte(byte));
       return Future.wait(writes, eagerError: true).then((_) => true);
     }
   
  -  Future<bool> _writeOneByte(int byte){
  +  Future _writeOneByte(int byte){
       _checkOpen();
       final completer = new Completer<bool>();
       final replyPort = new ReceivePort();
       _servicePort.send([replyPort.sendPort, _WRITE_BYTE_METHOD, _ttyFd, byte]);
       replyPort.first.then((result) {
         if (result[0] == null) {
  -        completer.complete(true);
  +        completer.complete();
         } else {
           completer.completeError("Cannot write in $portname : ${result[0]}");
         }
  
positive.code: 
    /// Read data send from the serial port
    Stream<List<int>> get onRead {
      StreamController<String> controller = new StreamController();
      _onReadControllers.add(controller);
      return controller.stream;
    }
  
negative.code:   }
  
    /// Write as a string
    Future writeString(String data){
      _checkOpen();
      final completer = new Completer<bool>();
      final replyPort = new ReceivePort();
      _servicePort.send([replyPort.sendPort, _WRITE_METHOD, _ttyFd, data]);
      replyPort.first.then((result) {
        if (result[0] == null) {
          completer.complete();
        } else {
          completer.completeError("Cannot write in $portname : ${result[0]}");
        }
  