socket基础

服务端代码

void TCPServer()
{
    //创建服务器socket
    SOCKET  socketServer = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
    if (INVALID_SOCKET == socketServer)
    {
        return;
    }
    //绑定IP和端口
    struct sockaddr_in  serverAddr = {0};
    serverAddr.sin_family = AF_INET;
    serverAddr.sin_port = htons(5780);
    serverAddr.sin_addr.S_un.S_addr = htonl(INADDR_ANY);//绑定本机所有IP
    bind(socketServer,(struct sockaddr*)&serverAddr, sizeof(serverAddr));

    //侦听
    listen(socketServer, SOMAXCONN);

    printf("等候客户端链接。。。。。\n");

    //等候客户端
    struct sockaddr_in clientAddr = {0};
    int nLen = sizeof(clientAddr);
    SOCKET sockClient = accept(socketServer, (sockaddr*)&clientAddr,&nLen);//阻塞函数  等候客户端的链接并返回链接好的 套接字

    //数据收发
    printf("客户端已经链接。。。。。\n");

    char szText[100] = { 0 };
    recv(sockClient, szText, 100, 0);//阻塞函数
    printf("%s", szText);
    char szSend[100] = "Hello  我是服务器";
    send(sockClient, szSend, sizeof(szSend), 0);

    _getch();

    //关闭socket
    closesocket(sockClient);
    closesocket(socketServer);
}

客户端代码：

void TCPClient()
{
    //////////////////////////////////////////////////////////////////////////
    //创建socket

    SOCKET sockClient = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
    if (INVALID_SOCKET == sockClient)
    {
        return;
    }

    //链接到服务器
    struct sockaddr_in addr = { 0 };
    addr.sin_family = AF_INET;
    addr.sin_port = htons(5780);
    addr.sin_addr.S_un.S_addr = inet_addr("127.0.0.1");//当前机器的IP地址

    connect(sockClient, (struct sockaddr*)&addr, sizeof(addr));//需要指定链接的服务器的IP地址 和端口

    //数据的收发
    printf("链接服务器。。。。。\n");
    char szSend[100] = "Hello 我是客户端";
    send(sockClient, szSend, sizeof(szSend), 0);

    char szRecv[100] = { 0 };
    recv(sockClient, szRecv, sizeof(szRecv), 0);
    printf("%s", szRecv);


    getch();
    //关闭socket
    closesocket(sockClient);

}