C + + Socket programming steps

Sockets (sockets) are programmed with three types of streaming sockets (SOCK_STREAM), datagram Sockets (SOCK_DGRAM), raw Sockets (Sock_raw), and TCP-based socket programming as a streaming socket.

Steps for server-side programming:

1: Load socket font, create socket (WSAStartup ()/socket ());

2: Bind sockets to an IP address and a port (bind ());

3: Set socket to listening mode waiting for connection request (listen ());

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

5: Communicates with the client using the returned socket (send ()/recv ());

6: Return, wait for another connection request;

7: Close the socket and close the loaded socket font (closesocket ()/wsacleanup ()).

Client-side programming steps:

1: Load socket font, create socket (WSAStartup ()/socket ());

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

3: Communicate with the server (send ()/recv ());

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

First: Load/release Winsock library:

1. Loading method:

Wsadata WSA;
/* Initialize the socket resource */
if (WSAStartup (Makeword), &WSA)! = 0)
{
Return Representative failure
}

2. Release method:

WSACleanup ();

Second type: Construct socket:

1. Server: Construct the monitor socket, stream socket.
Socket Listen_sock = socket (af_inet, sock_stream, 0)

2. Client: Constructs communication socket, streaming socket.
Socket Client_sock = socket (af_inet, sock_stream, 0)

The third type: Configure the listening address and port:

1. Service side: sockaddr_in serveraddr
ZeroMemory (char *) &serveraddr, sizeof (serveraddr));
serveraddr. sin_family = af_inet;
serveraddr. Sin_port = htons (1234); /* Local listening port: 1234*/
serveraddr. sin_addr.s_addr = htonl (inaddr_any); /* with ip*/

Type IV: BIND socket:

1. Server: Bind listening socket.
bind (listen_sock,(struct sockaddr *) &serveraddr,sizeof (serveraddr))

Type V: Server/Client Connection:

1. Server: Waiting for client access.
SOCKET Command_sock = Accept (listen_sock, ...)

2. Client: The request is connected to the server.
int ret = connect (client_sock, ...)

Type VI: Collect/Send data:

1. Server: Wait for client access. Char buf[1024].
Data received: recv (command_sock, buf, ...)
Or
Send data: Send (command_sock, buf, ...)

2. Client: The request is connected to the server. Char buf[1024].
Send data: Send (Client_sock, buf, ...)
Or
Receive data: recv (Client_sock, buf, ...)

Type seventh: Close socket:

1. Server: Close socket.
Closesocket (listen_sock)
Closesocket (command_sock)

2. Client: Close the socket.
Closesocket (client_sock)

#include <stdio.h>#include <Winsock2.h>voidmain(){ WORD wVersionRequested; WSADATA wsaData; interr;  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; intlen=sizeof(SOCKADDR); while(1) {  SOCKET sockConn=accept(sockSrv,(SOCKADDR*)&addrClient,&len);  charsendBuf[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); }}

#include <stdio.h>
#include <Winsock2.h>
void Main ()
{
WORD wversionrequested;
Wsadata 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 ();
} 

C + + Socket programming steps