What is required to make DynamicTcpClientApplication also return data with the send interface?

I'm trying to wrap my head around how to make the DynamicTcpClientApplication also give back the response data sent with:

	@MessagingGateway(defaultRequestChannel = "toTcp.input")
	public interface ToTCP {

		public void send(String data, @Header("host") String host, @Header("port") int port);

	}

Just changing from void to byte[] is not enough. What is needed to make sure a client can get the response from a tcp request back through the interface?

Start by reading the DynamicTcpClientApplication sample and the ToTCP MessagingGateway interface shown in the issue. Trace how the TCP request and response are connected, then determine what request-reply behavior is required so the interface can return response data rather than void; the work is done when that behavior is demonstrated in the sample.