anchor.diff:          startResponse(req.socket, fileList[path]);
         }
       });
  -  }).catchError((e){
  +  }).catchError((e) {
       completer.completeError(e);
     });
     return completer.future;
  
positive.code: 
  async.Future<int> startServer() {
    print("startServer");
    async.Completer<int> completer = new async.Completer();
    if (_server != null) {
      completer.completeError({});
  
negative.code: hetima.HetiHttpServer _server = null;
  
  void startPortMap() {
    hetima.UpnpDeviceSearcher.createInstance(new hetimacl.HetiSocketBuilderChrome()).then((hetima.UpnpDeviceSearcher searcher) {
      searcher.searchWanPPPDevice().then((int e) {
        if (searcher.deviceInfoList.length <= 0) {
          return;
        }
        hetima.UPnpDeviceInfo info = searcher.deviceInfoList.first;
  