Linux Server-prototype of Client Communication

Server program compiled in Linux

# Include
# Include
# Include
# Include

# Define maxline 100
# Define SA struct sockaddr
# Define socket int

Using namespace STD;

Int main ()
{
Cout <"this is a server! "<Endl;
Struct sockaddr_in server, client;

Socket listen_sock = socket (af_inet, sock_stream, 0); // create a listener socket
If (listen_sock <0)
{
Perror ("socket error ");
Return-1;
}

Memset (char *) & server, 0, sizeof (server ));
Server. sin_family = af_inet;
Server. sin_port = htons (8888 );
If (BIND (listen_sock, (Sa *) & server, sizeof (server) <0) // bind the listening port
{
Perror ("BIND error ");
Return-1;
}

Listen (listen_sock, 5); // listen to sockfd a backlog queue bound to an unconnected socket Descriptor
 
Socklen_t n = (socklen_t) sizeof (client );
Socket conn_sock = (socket) accept (listen_sock, (Sa *) & client, & N); // create a connection socket
If (conn_sock <0)
Perror ("Accept error ");
Else
{
// Accept client request information
Unsigned char Buf [maxline + 1];
Memset (BUF, 0, sizeof (BUF ));
If (n = Recv (conn_sock, Buf, maxline, 0) <0)
Perror ("Recv error ");
Else
{
Buf [N] = 0;
Cout <"Recv from client:" <Buf <Endl;
}
// Server processing service ///
//////
////////////////////

// Return the server processing result string
If (send (conn_sock, "server! ", 7, 0) <0)
Perror ("send error ");
 
Close (conn_sock );
}
Close (listen_sock );
Return 0;
}

Client Program

# Include
# Include
# Include
# Include
# Include

# Define maxline 100
# Define SA struct sockaddr
# Define socket int

Using namespace STD;

Const char * IP = {"127.0.0.1 "};
Const int Port = 8888;

Int main ()
{
Cout <"this is a client! "<Endl;
Cout <"conn Server IP:" <IP <Endl;
Cout <"conn server port:" <port <Endl;

Socket sockfd;
If (sockfd = socket (af_inet, sock_stream, 0) <0)
{// Create a socket, TCP protocol, stream socket, and communication protocol
Perror ("socket error ");
Return-1;
}
Struct sockaddr_in servaddr; // communication address type variable
Memset (& servaddr, 0, sizeof (servaddr ));
Servaddr. sin_family = af_inet;
Servaddr. sin_port = htons (port );
Struct hostent * HP;
HP = gethostbyname (IP );
Memcpy (char *) & servaddr. sin_addr, (char *) HP-> h_addr, HP-> h_length );

If (connect (sockfd, (Sa *) & servaddr, sizeof (servaddr) <0) // establish a connection
{
Perror ("Connect error ");
Return-1;
}

Cout <"you:" <Endl;
String message;
Cin> message;
If (send (sockfd, message. c_str (), message. Size (), 0) <0) // send the request string
{
Perror ("send error ");
Return-1;
}

Int N;
Char recvline [maxline + 1];
While (n = Recv (sockfd, recvline, maxline, 0)> 0) // accept, blocking
{
Recvline [N] = 0;
Cout <"Recv from server:" <recvline <Endl;
}
If (n <0)
Perror ("Recv error ");

Close (sockfd); // close the socket connection

Return 0;
}