Winsock Simple Communication

Header file

#include <WinSock2.h>

#include <string>

#include <WS2tcpip.h>

#include <IPHlpApi.h>

#include <stdio.h>

#pragma comment (lib, "Ws2_32.lib")

Source

Initialize Winsock

Wsadata Wsadata;

int Iresult;

Iresult = WSAStartup (Makeword (2, 2), &wsadata);

if (Iresult! = 0) {

printf ("WSAStartup failed:%d\n", Iresult);

return NULL;

}

Get Connection Properties

struct Addrinfo * result = NULL, *PTR = null, hints;

ZeroMemory (&hints, sizeof (hints));

hints.ai_family = af_inet;

Hints.ai_socktype = Sock_stream;

Hints.ai_protocol = ipproto_tcp;

Iresult = getaddrinfo ("192.168.0.18", "7002", &hints, &result);

Iresult = getaddrinfo ("192.168.37.187", "7002", &hints, &result);

if (Iresult! = 0) {

printf ("Getaddrinfo failed:%d\n", Iresult);

WSACleanup ();

return NULL;

}

Creating a Socket Object

ptr = result;

SOCKET connectsocket = Invalid_socket;

Connectsocket = socket (ptr->ai_family, Ptr->ai_socktype, Ptr->ai_protocol);

if (Connectsocket = = Invalid_socket) {

printf ("Error at Socket ():%ld\n", WSAGetLastError ());

Freeaddrinfo (result);

WSACleanup ();

return NULL;

}

Link

Iresult = Connect (Connectsocket, ptr->ai_addr, (int) ptr->ai_addrlen);

if (Iresult = = Socket_error) {

printf ("Error at Socket ():%ld\n", WSAGetLastError ());

Closesocket (Connectsocket);

Connectsocket = Invalid_socket;

}

int nsendbuf = 32 * 1000;//set to 32K

SetSockOpt (Connectsocket, Sol_socket, So_rcvtimeo, (const char*) &nsendbuf, sizeof (int));

Should really try the next address returned by Getaddrinfo

If the Connect call failed

Example we just free the resources

Returned by getaddrinfo and print an arror message

Freeaddrinfo (result);

if (Connectsocket = = Invalid_socket) {

printf ("Unable to connect to server!\n");

WSACleanup ();

return NULL;

}

Send (Connectsocket, Strsendcontext.c_str (), Strsendcontext.length (), 0);

Char szbuffer[1024] = {0};

Recv (Connectsocket, Szbuffer, 1024, 0);

:: Closesocket (Connectsocket);

Description

Automated testing of current inline code

Winsock Simple Communication