Windows C-Language Socket programming example (TCP and UDP)

1 TCP Server Side

#include "stdafx.h" #include <stdio.h> #include <winsock2.h> #pragma comment (lib, "Ws2_32.lib") int main (int
    ARGC, char* argv[]) {//initialize WSA WORD sockversion = Makeword (2,2);
    Wsadata Wsadata;
    if (WSAStartup (sockversion, &wsadata)!=0) {return 0;
    ///Create socket Socket Slisten = socket (af_inet, sock_stream, ipproto_tcp);
        if (Slisten = = Invalid_socket) {printf ("SOCKET error!");
    return 0;
    }//Binding IP and Port sockaddr_in sin;
    sin.sin_family = af_inet;
    Sin.sin_port = htons (8888); Sin.sin_addr. S_un. 
    S_ADDR = Inaddr_any;
    if (Bind (Slisten, (lpsockaddr) &sin, sizeof (sin)) = = Socket_error) {printf ("Bind ERROR!");
        //Start listening if (Listen (Slisten, 5) = = Socket_error) {printf ("Listen ERROR!");
    return 0;
    ///loop receive data SOCKET sclient;
    Sockaddr_in remoteaddr;
    int naddrlen = sizeof (REMOTEADDR); 
    Char revdata[255];
    while (true) {    printf ("Wait for connection ... \ n");
        Sclient = Accept (Slisten, (SOCKADDR *) &remoteaddr, &naddrlen);
            if (sclient = = Invalid_socket) {printf ("Accept error!");
        Continue
        
        printf ("Accept a connection:%s \ r \ n", Inet_ntoa (REMOTEADDR.SIN_ADDR));        
        Receive data int ret = recv (sclient, Revdata, 255, 0);
            if (Ret > 0) {Revdata[ret] = 0x00;
        printf (revdata); //Send Data char * senddata = "Hello, tcp client."
        \ n ";
        Send (Sclient, SendData, strlen (SendData), 0);
    Closesocket (sclient);
    } closesocket (Slisten);
    WSACleanup ();
return 0; }

     client End

#include "stdafx.h" #include <winsock2. H> #include <stdio.
    h> #pragma comment (lib, "Ws2_32.lib") int main (int argc, char* argv[]) {WORD sockversion = Makeword (2,2); 
    Wsadata data;
    if (WSAStartup (sockversion, &data)!= 0) {return 0;
    Socket sclient = socket (af_inet, sock_stream, ipproto_tcp);
        if (sclient = = Invalid_socket) {printf ("INVALID SOCKET!");
    return 0;
    } sockaddr_in seraddr;
    seraddr.sin_family = af_inet;
    Seraddr.sin_port = htons (8888); Seraddr.sin_addr. S_un. 
    S_ADDR = inet_addr ("127.0.0.1"); 
        if (Connect (sclient, (SOCKADDR *) &seraddr, sizeof (seraddr)) = = Socket_error) {printf ("Connect ERROR!");
        Closesocket (sclient);
    return 0;
    char * senddata = "Hello, tcp server, I am client!\n";

    Send (Sclient, SendData, strlen (SendData), 0);
    Char recdata[255];
    int ret = recv (sclient, Recdata, 255, 0);
if (Ret > 0) {Recdata[ret] = 0x00;        printf (recdata);
    } closesocket (sclient);
    WSACleanup ();
return 0; }

2 UDP Server Side

#include "stdafx.h" #include <stdio.h> #include <winsock2.h> #pragma comment (lib, "Ws2_32.lib") int main (in
    T argc, char* argv[]) {wsadata wsadata;
    WORD sockversion = Makeword (2,2);
    if (WSAStartup (sockversion, &wsadata)!= 0) {return 0; 
    Socket sersocket = socket (af_inet, SOCK_DGRAM, IPPROTO_UDP);
        if (Sersocket = = Invalid_socket) {printf ("SOCKET error!");
    return 0;
    } sockaddr_in seraddr;
    seraddr.sin_family = af_inet;
    Seraddr.sin_port = htons (8888); Seraddr.sin_addr. S_un.
    S_ADDR = Inaddr_any;
        if (Bind (Sersocket, (SOCKADDR *) &seraddr, sizeof (seraddr)) = = Socket_error) {printf ("Bind ERROR!");
        Closesocket (Sersocket);
    return 0;
    } sockaddr_in remoteaddr; 
    int naddrlen = sizeof (REMOTEADDR);  
        while (true) {char recvdata[255];
int ret = Recvfrom (Sersocket, RecvData, 255, 0, (SOCKADDR *) &remoteaddr, &naddrlen);        if (Ret > 0) {Recvdata[ret] = 0x00;
            printf ("Accepted to a connection:%s \ r \ n", Inet_ntoa (REMOTEADDR.SIN_ADDR));            
        printf (recvdata);
        char * senddata = "A UDP packet from the server \ n";    

    SendTo (Sersocket, SendData, strlen (SendData), 0, (SOCKADDR *) &remoteaddr, Naddrlen); 
    } closesocket (Sersocket);
    WSACleanup ();
return 0; }

Client Side

#include "stdafx.h"
#include <stdio.h>
#include <winsock2.h>

#pragma comment (lib, "ws2_32. Lib ") 

int main (int argc, char* argv[])
{
    WORD socketversion = Makeword (2,2);
    Wsadata Wsadata; 
    if (WSAStartup (socketversion, &wsadata)!= 0)
    {return
        0;
    }
    Socket sclient = socket (af_inet, SOCK_DGRAM, ipproto_udp);
    
    Sockaddr_in sin;
    sin.sin_family = af_inet;
    Sin.sin_port = htons (8888);
    Sin.sin_addr. S_un. S_ADDR = inet_addr ("127.0.0.1");
    int len = sizeof (sin);
    
    char * senddata = "Packets from the client. \ n";
    SendTo (Sclient, SendData, strlen (SendData), 0, (SOCKADDR *) &sin, Len);

    Char recvdata[255];     
    int ret = Recvfrom (sclient, RecvData, 255, 0, (SOCKADDR *) &sin, &len);
    if (Ret > 0)
    {
        Recvdata[ret] = 0x00;
        printf (recvdata);
    }

    Closesocket (sclient);
    WSACleanup ();
    return 0;
}

Blog Original: http://blog.csdn.net/oinux/article/details/8525823