windows网络编程

TCP编程

服务端

这里我们有几点需要注意:

使用WSAStartup初始化网络库,即将与socket函数相关dll文件加载到进程地址空间中
退出时,使用WSACleanup()卸载相关dll文件
与Linux使用close函数关闭socket不同,windows需要使用closesocket函数关闭socket

WSAStartup函数和WSACleanup函数是线程相关的,任何一个线程都可以调用,对于WSAStartup函数,某一个线程调用后,其他线程不需要调用,也可以使用;

如果某个线程不在调用socket相关函数,调用WSACleanup函数,那么其他需要调用socket相关函数的线程将无法调用,所以我们应该在整个程序退时调用WACleanup函数

#include <WinSock2.h>
#include <stdio.h>
#include <stdlib.h>
#pragma comment(lib, "ws2_32.lib")
int main()
{printf("Server\n");//1 初始化网络库 // 加载套接字库WORD wVersionRequested;WSADATA wsaData;int err;wVersionRequested = MAKEWORD(2, 2);// 1、初始化套接字库err = WSAStartup(wVersionRequested, &wsaData);if (err != 0){printf("WSAStartup errorNum = %d\n", GetLastError());return err;}if (LOBYTE(wsaData.wVersion) != 2 || HIBYTE(wsaData.wVersion) != 2){printf("LOBYTE errorNum = %d\n", GetLastError());WSACleanup();return -1;}// 2 安装电话机 // 新建套接字SOCKET sockSrv = socket(AF_INET, SOCK_STREAM, 0);if (INVALID_SOCKET == sockSrv){printf("socket errorNum = %d\n", GetLastError());return -1;} //给变量配置电话号码 IP 任何 端口 6000SOCKADDR_IN addrSrv;addrSrv.sin_addr.S_un.S_addr = htonl(INADDR_ANY);addrSrv.sin_family = AF_INET;addrSrv.sin_port = htons(6000); // 3 分配电话号码 // 绑定套接字到本地 IP 地址，端口号 6000if (SOCKET_ERROR == bind(sockSrv, (SOCKADDR*)&addrSrv, sizeof(SOCKADDR))){printf("bind errorNum = %d\n", GetLastError());return -1;} // 4、监听 listenif (SOCKET_ERROR == listen(sockSrv, 5)){printf("listen errorNum = %d\n", GetLastError());return -1;} // 5、拿起话筒，准备通话SOCKADDR_IN addrCli;int len = sizeof(SOCKADDR);while (TRUE){//6、分配一台分机去服务SOCKET sockConn = accept(sockSrv, (SOCKADDR*)&addrCli, &len);char sendBuf[100] = {0};sprintf_s(sendBuf, 100, "Welcome %s to bingo!", inet_ntoa(addrCli.sin_addr));//发送数据int iLen = send(sockConn, sendBuf, strlen(sendBuf) + 1, 0);if (iLen < 0){printf("send errorNum = %d\n", GetLastError());return -1;}char recvBuf[100] = {0}; //接收数据iLen = recv(sockConn, recvBuf, 100, 0);if (iLen < 0){printf("recv errorNum = %d\n", GetLastError());return -1;} //打印接收的数据printf("recvBuf = %s\n", recvBuf);closesocket(sockConn);}//7 关闭总机closesocket(sockSrv);WSACleanup();system("pause");return 0;
}

客户端

#include <iostream>
#include <WinSock2.h>
#include <stdio.h>
#include <stdlib.h>
#pragma comment(lib, "ws2_32.lib")
int main()
{printf("Client\n");//1 初始化网络库 // 加载套接字库WORD wVersionRequested;WSADATA wsaData;int err;wVersionRequested = MAKEWORD(2, 2);// 1、初始化套接字库err = WSAStartup(wVersionRequested, &wsaData);if (err != 0){printf("WSAStartup errorNum = %d\n", GetLastError());return err;}if (LOBYTE(wsaData.wVersion) != 2 || HIBYTE(wsaData.wVersion) != 2){printf("LOBYTE errorNum = %d\n", GetLastError());WSACleanup();return -1;}// 2 安装电话机 // 新建套接字SOCKET sockCli = socket(AF_INET, SOCK_STREAM, 0);if (INVALID_SOCKET == sockCli){printf("socket errorNum = %d\n", GetLastError());return -1;}//配置要连接服务器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);//连接服务器if (SOCKET_ERROR == connect(sockCli, (SOCKADDR*)&addrSrv, sizeof(SOCKADDR))){printf("connect errorNum = %d\n", GetLastError());return -1;}//收发数据char recvBuf[100] = { 0 };int iLen = recv(sockCli, recvBuf, 100, 0);std::cout << recvBuf << std::endl;char sendBuf[100] = "hello";iLen = send(sockCli, sendBuf, 100, 0);closesocket(sockCli);WSACleanup();
}