tcp/udp sender client and server

// example of threaded receive / sender on either TCP or UDP
//
// sudo apt-get install libsfml-dev
// to make master ::
// g++-8 -Wconversion -std=c++11 -c client_socket.cpp -lpthread -lsfml-graphics -lsfml-window -lsfml-system -lsfml-network
// g++-8 -std=c++11 client_socket.o -o sfml-app-m -lsfml-graphics -lsfml-window -lsfml-system -lsfml-network -lpthread
// for slave :: comment out SFML_MASTER
// g++-8 -Wconversion -std=c++11 -c client_socket.cpp -lpthread -lsfml-graphics -lsfml-window -lsfml-system -lsfml-network
// g++-8 -std=c++11 client_socket.o -o sfml-app-s -lsfml-graphics -lsfml-window -lsfml-system -lsfml-network -lpthread
//
#include<SFML/Network.hpp>
#include<iostream>
#include<string>
#include<thread>

using namespace std;
using namespace sf;

/* uncomment if you want UDP
#define ON_UDP
*/

#ifndef SFML_BLOCKING
#define SFML_BLOCKING false                                             // no blocking socket
#else
#define SFML_BLOCKING true                                              // blocking socket
#endif

#define SFML_MASTER                                                     // comment this out for slave

#if defined(ON_UDP)
void Send()                                                             //Send message.
{
    while (true)
    {
        UdpSocket socket;                                               //define UDP socket for transmit
        char message[250]; Packet packet;

        cin.getline(message, 250);                                      //get keyboard message
        packet << message;
#if defined(SFML_MASTER)
        socket.send(packet, "127.0.0.1", 2001);
#else
        socket.send(packet, "127.0.0.1", 2002);
#endif

    }
}
void Receive()                                                          // receive message
{
    while (true)
    {
#if defined(SFML_MASTER)
        UdpSocket socket; socket.bind(2002);                            //define UDP socket for receive
#else
        UdpSocket socket; socket.bind(2001);                            //define UDP socket for receive
#endif
        IpAddress sender; unsigned short port; string message; Packet packet;       // Get a message from someone.
        socket.setBlocking(SFML_BLOCKING);
        socket.receive(packet, sender, port);
        packet >> message;
        cout << message << endl;
    }
}
//------- Protocol Udp  ----------------+
int main()
{
    cout << "UDP messanger" << endl; cout << "--------" << endl;

    thread receive(Receive); thread send(Send);                         //Call 2 functions each in a separate thread


    receive.join(); send.join();                                        // Wait for the threads to finish working.
    size_t z; cin >> z; return 0;
}

#else /* on TCP */

#include<SFML/Network.hpp>
#include<iostream>
#include<string>
#include<thread>

using namespace std;
using namespace sf;

void Send()                                                             //Send operation
{
    while (true)
    {

        TcpSocket socket;                                               //define transmit socket
#if defined(SFML_MASTER)
        socket.connect("127.0.0.1", 2001);                              // CLIENT :: connect to ip
#else
        socket.connect("127.0.0.1", 2002);                              // CLIENT :: connect to ip
#endif
        char message[250]; Packet packet;

        cin.getline(message, 250);                                      //  get keyboard message
        packet << message;
        socket.send(packet);
        packet.clear();
    }
}
void Receive()                                                          //receive operation
{
    while (true)
    {
        TcpSocket socket;                                               // Define receive socket
        socket.setBlocking(SFML_BLOCKING);
#if defined(SFML_MASTER)
        TcpListener listener; listener.listen(2002);                    // Server :: Create a listener socket, assign a port to it, and go into standby mode.
#else
        TcpListener listener; listener.listen(2001);                    // Server :: Create a listener socket, assign a port to it, and go into standby mode.
#endif
        listener.accept(socket);                                        // Establish a connection with the subscriber, if he sent the request.
        string message; Packet packet;                                  // Get a message from the caller.

        socket.receive(packet);
        packet >> message;
        cout << message << endl;
    }
}
//------- Protocol Tcp  ----------------+
int main()
{
    cout << "TCP messager" << endl; cout << "---------------" << endl;
    thread receive(Receive); thread send(Send);

    receive.join(); send.join();
    size_t z; cin >> z; return 0;
}
#endif