Socket programming steps in VC

There are three types of socket programming: stream socket (sock_stream), datagram socket (sock_dgram), and original socket (sock_raw). TCP-based socket programming is a streaming socket. In this program, add two projects to a work zone. Link a library file of ws2_32.lib.

Server programming steps:

1: load the socket library and create a socket (wsastartup ()/socket ());

2: bind a socket to an IP address and a port (BIND ());

3: Set the socket to listening mode and wait for the connection request (Listen ());

4: after the request arrives, accept the connection request and return a new socket (accept () corresponding to the connection ());

5: Use the returned socket to communicate with the client (send ()/Recv ());

6: return. Wait for another connection request;

7. Close the socket and the loaded socket Library (closesocket ()/wsacleanup ()).

 

The server code is as follows:

# Include <stdio. h>
# Include <winsock2.h>
Void main ()
{
Word wversionrequested;
Wsadata;
Int err;
 
Wversionrequested = makeword (1, 1 );
 
Err = wsastartup (wversionrequested, & wsadata );
If (Err! = 0 ){
Return;
}
 
If (lobyte (wsadata. wversion )! = 1 |
Hibyte (wsadata. wversion )! = 1 ){
Wsacleanup ();
Return;
}
Socket socksrv = socket (af_inet, sock_stream, 0 );

Sockaddr_in addrsrv;
Addrsrv. sin_addr.s_un.s_addr = htonl (inaddr_any );
Addrsrv. sin_family = af_inet;
Addrsrv. sin_port = htons (6000 );
 
BIND (socksrv, (sockaddr *) & addrsrv, sizeof (sockaddr ));

Listen (socksrv, 5 );

Sockaddr_in addrclient;
Int Len = sizeof (sockaddr );
While (1)
{
Socket sockconn = accept (socksrv, (sockaddr *) & addrclient, & Len );
Char sendbuf [50];
Sprintf (sendbuf, "Welcome % s to here! ", Inet_ntoa (addrclient. sin_addr ));
Send (sockconn, sendbuf, strlen (sendbuf) + 1, 0 );
Char recvbuf [50];
Recv (sockconn, recvbuf, 50, 0 );
Printf ("% s \ n", recvbuf );
Closesocket (sockconn );
}
}

 

Client programming steps:

1: load the socket library and create a socket (wsastartup ()/socket ());

2: Send a connection request (connect () to the server ());

3: communicate with the server (send ()/Recv ());

4: Close the socket and close the loaded socket Library (closesocket ()/wsacleanup ()).

 

The client code is as follows:

# Include <stdio. h>
# Include <winsock2.h>
Void main ()
{
Word wversionrequested;
Wsadata;
Int err;
 
Wversionrequested = makeword (1, 1 );
 
Err = wsastartup (wversionrequested, & wsadata );
If (Err! = 0 ){
Return;
}
 
If (lobyte (wsadata. wversion )! = 1 |
Hibyte (wsadata. wversion )! = 1 ){
Wsacleanup ();
Return;
}
Socket sockclient = socket (af_inet, sock_stream, 0 );
 
Sockaddr_in addrsrv;
Addrsrv. sin_addr.s_un.s_addr = inet_addr ("127.0.0.1 ");
Addrsrv. sin_family = af_inet;
Addrsrv. sin_port = htons (6000 );
Connect (sockclient, (sockaddr *) & addrsrv, sizeof (sockaddr ));
Send (sockclient, "hello", strlen ("hello") + 1, 0 );
Char recvbuf [50];
Recv (sockclient, recvbuf, 50, 0 );
Printf ("% s \ n", recvbuf );
 
Closesocket (sockclient );
Wsacleanup ();
}