Socket network Programming-Windows-based

First, socket programming

Run the server first, this article uses threads to run the server, and then run the client.

Ii. Basic Concepts

IP: Can uniquely identify a host on the network;

Protocol + port: can uniquely identify a process in the host;

So the process in the host is identified by ip+ Protocol + port triples.

Third, the realization of programming

#pragma  once#define WIN32#include<iostream> #include <stdio.h> #include   "stdafx.h" # include<sys/types.h> #include <WS2tcpip.h> #pragma  comment (lib,  "Ws2_32.lib") using  Namespace std;//typedef int (*dllfunc) (int,int);//int is the type of the method parameter, with several parameters defined. Typedef int (*DLLFUNC2) ();D Word winapi threadfunc (handle thread) {//HINSTANCE  Hinstlibrary = loadlibrary (_t ("e:\\v3.0\\ new Folder \\MyDll.dll"));//To write clear path, note double slash//if  (GetLastError ()  != 0)//{//std::cout << getlasterror ();//Print Failure message//}//if  (hinstlibrary ==  null)//{//freelibrary (hinstlibrary);//return 0;//}//dllfunc2 dllfunc3;//dllfunc3 =  ( DLLFUNC2) GetProcAddress (hinstlibrary,  "Socketsevert");//int i3 = dllfunc3 ();//cout  << i3 << endl;//freelibrary (hinstlibrary);//server-side   0 succeeded; 22 sockets; 3 bindings; 4 Listening word  sockversion = makeword (2,&NBSP;2); Wsadata wsaData;if  (WSAStartup (sockversion, &wsadata)  != 0) {printf ("-3");//return - 3;}   Create communication endpoint: Socket Int sockfd = socket (af_inet, sock_stream, 0);if  (sockfd  < 0) {printf ("the server created the socket failed!") \ n ");} else{printf ("Server created socket succeeded! \ n ");} Struct sockaddr_in my_addr;my_addr.sin_family = af_inet;my_addr.sin_port = htons (8888); my_addr.sin_addr.s_addr = htonl (inaddr_any);//Binding Int err_log = bind (SOCKFD,   (struct sockaddr*) &my_addr, sizeof (MY_ADDR));if  (err_log != 0) {printf (" Server bindings failed! \ n ");} else{printf ("Server bindings succeeded! \ n ");} Monitor Err_log = listen (sockfd, 10);if  (err_log != 0) {printf ("Server Listener failed!") \ n ");} else{printf ("Server monitoring succeeded! \ n ");} Sleep (;int i = 0;while ) (1) {I++;struct sockaddr_in client_addr;char cli_ ip[inet_addrstrlen] =  ""; socklen_t cliaddr_len = sizeof (client_addr);//Successful return of a new sockThe ET file descriptor, used to communicate with the client, failed to return -1//indicates that the three-party handshake is complete, and the next server calls accept () accepts the connection int connfd = accept (sockfd,  (struct  sockaddr*) &client_addr, &cliaddr_len);if  (connfd < 0) {printf ("Accept% D-time failure \ n ", i); continue;} else{printf ("Accept%d successes \ n",  i);} Receive Data char recv_buf[512] = { 0 };while  (recv (connfd, recv_buf, sizeof ( RECV_BUF),  0)  > 0) {i = sizeof (recv_buf);while  (i--) printf ("Receive data: \n%c\n", recv_ Buf[i]);}} return 0;} Int main () {//dllfunc2 dllfunc2;//// hdll=loadlibraryex ("*.dll",  null, load_with_ Altered_search_path), use this statement//hinstance hinstlibrary = loadlibrary (_t ("e:\\v3.0\") if there are calls to other DLLs in the DLL library. \ New Folder \\MyDll.dll "));//To write clear path, note double slash//if  (GetLastError ()  != 0)//{//std::cout <<  GetLastError ();//Print failure Information//}//if  (hinstlibrary == null)//{//freelibrary (hinstlibrary);//return  0;//}//Thread---server handle thread;dword&nBsp;dwthreadid; Thread = ::createthread (Null, 0, threadfunc, null, 0, &dwthreadid);// cout <<  "THE&NBSP;NEW&NBSP;THREAD&NBSP;ID&NBSP;IS&NBSP;:"  << dwThreadId  << endl;//client Word sockversion = makeword (2,&NBSP;2); wsadata wsadata;if  (WSAStartup (sockversion, &wsadata)  != 0) {return -1;} socket sockclient = null; Sockaddr_in addrsrv;//addrsrv.sin_addr. S_un. S_ADDR&NBSP;=&NBSP;INET_ADDR ("127.0.0.1"); Inet_pton (af_inet,  "128.0.0.1",  (void*) &addrsrv.sin_ Addr. S_un. S_ADDR); addrsrv.sin_family = af_inet;addrsrv.sin_port = htons (8888);//Create Socket Sockclient  = socket (af_inet, sock_stream, 0);if  (sockclient < 0) {printf ("Create socket failed! \ n ");} else{printf ("Create socket succeeded! \ n ");} Network connection if  (Connect (sockclient,  (sockaddr*) &addrsrv, sizeof (sockaddr))  == socket_ ERROR) {printf ("Connect lostDefeat! \ n ");} else{printf ("Network connection is successful! \ n ");char send_buf[12] = {  ' C ', ' d '  };int nrecv = ::send (SockClient,  send_buf, sizeof (SEND_BUF),  0);if  (nrecv < 0) {printf ("Send failed! \ n ");} ELSE{PRINTF ("Sent successfully! \ n ");}} Socketconnect is a method defined in the DLL library//dllfunc2 =  (DLLFUNC2) GetProcAddress (hinstlibrary,  "Socketconnect") ;//if  (dllfunc2 == null)//{//freelibrary (hinstlibrary);//return 0;//}//int i2 =  dllfunc2 ();//cout << i2 << endl;//freelibrary (HInstLibrary);:: WaitForSingleObject (Thread, infinite);:: CloseHandle (Thread); return 0;}

Socket network Programming-Windows-based