将asio udp套接字发送到不同的ip地址

Question

I have one udp server receiving messages from multiple remote clients. When it receives one message, I copy the endpoint and reply to the client at the same IP address on port 5000 where each client is listening.

I have tried multiple debbuging strategies, and printing the endpoint right before I send the reply message gives me the correct IP address and port.

The sender:

    std::cout << udp_remote_endpoint.address().to_string();
    std::string str(packet.begin(), packet.end());
    std::cout << str << std::endl;
    io_service.post(
        [this, packet]()
        {
            udp_socket.async_send_to(
                boost::asio::buffer(packet),
                udp_remote_endpoint,
                boost::bind(
                    &uds::handle_write,
                    this,
                    boost::asio::placeholders::error,
                    boost::asio::placeholders::bytes_transferred
                )
            );
        }
            );

On the receiver, I get the udp_remote_endpoint and before sending, I set the socket endpoint:

    new_addr.endpoint = socket.get_udp_remote_endpoint();
    new_addr.endpoint.port(5000);
    socket.set_udp_remote_endpoint(new_addr.endpoint);

For example, this output:

192.168.1.131K-131-1559147491761155

Is actually sending to the IP 192.168.1.130. The message contents are correct "K-131-1559147491761155"

Answer 1

Solved!

I removed the io_service.post and it worked!

`std::cout << udp_remote_endpoint.address().to_string();
std::string str(packet.begin(), packet.end());
std::cout << str << std::endl;
//io_service.post(
//    [this, packet]()
//    {
        udp_socket.async_send_to(
            boost::asio::buffer(packet),
            udp_remote_endpoint,
            boost::bind(
                &uds::handle_write,
                this,
                boost::asio::placeholders::error,
                boost::asio::placeholders::bytes_transferred
            )
        );
//    }
//);`