code: func (pf *PortForwarder) waitForConnection(listener net.Listener, port ForwardedPort) {
  	for {
  		conn, err := listener.Accept()
  		if err != nil {
  			// TODO consider using something like https://github.com/hydrogen18/stoppableListener?
  			if !strings.Contains(strings.ToLower(err.Error()), "use of closed network connection") {
  				runtime.HandleError(fmt.Errorf("Error accepting connection on port %d: %v", port.Local, err))
  			}
  			return
  		}
  		go pf.handleConnection(conn, port)
  	}
  }
docs: // waitForConnection waits for new connections to listener and handles them in
  // the background.