anchor.diff:                        port.toSendPort());
         return;
       }
  -    var result = _FileUtils.writeList(_id, _buffer, _offset, _bytes);
  +    var result = _FileUtils._writeList(_id, _buffer, _offset, _bytes);
       _replyPort.send(result, port.toSendPort());
     }
   
  
positive.code:     if (index != 0) {
        throw new IndexOutOfRangeException(index);
      }
      int result = _FileUtils.writeList(_id, buffer, offset, bytes);
      if (result == -1) {
        throw new FileIOException("writeList failed");
      }
  
negative.code:     _scheduler.enqueue(operation, handleOpenResult);
    }
  
    RandomAccessFile openSync([FileMode mode = FileMode.READ]) {
      if (_asyncUsed) {
        throw new FileIOException(
            "Mixed use of synchronous and asynchronous API");
  