C++ WIN32 socket 客户端

#include<winsock2.h>//winsock的头文件
#include<iostream>
using  namespace  std;

//指定动态库的lib文件
#pragma comment(lib,"ws2_32.lib")


//TCP客户端
int main()
{

    //初始化winsock2.2相关的动态库
    WSADATA  wd;//获取socket相关信息
    if (WSAStartup(MAKEWORD(2, 2), &wd) != 0)//0表示成功
    {
        cout << "WSAStartup  error:" << WSAGetLastError() << endl;
        return 0;
    }


    //1.创建TCP   socket , 流式套接字
    SOCKET   s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
    if (s == INVALID_SOCKET)
    {
        cout << "socket  error:" << WSAGetLastError() << endl;
        return 0;
    }

    //2.链接服务端
    sockaddr_in   addr;//不建议使用sockaddr，建议用sockaddr_in
    addr.sin_port = htons(6000);//网络字节序
    addr.sin_addr.S_un.S_addr = inet_addr("127.0.0.1");//网络字节序
    addr.sin_family = AF_INET; //地址族
    int len = sizeof(sockaddr_in);
      
   if (connect(s, (sockaddr*)&addr, len) == SOCKET_ERROR)
   {
            cout << "connect  error:" << WSAGetLastError() << endl;
            return 0;
   }

   //3.接受发送消息
   int  ret = 0;
   do
   {
       //接受客户端的消息
       char buf[64] = { ‘\0‘ };
       ret = recv(s, buf, 64, 0);//把flag置0
       cout << "recv" << inet_ntoa(addr.sin_addr) << ":    " << buf << endl;// inet_ntoa转换为IP字符串

       //发送
       ret = send(s, "I am Client!", strlen("I am Client!"), 0);

       Sleep(1000);
   } while (ret != SOCKET_ERROR &&  ret != 0);


   //4.关闭套接字
   closesocket(s);

    //清理winsock环境
    WSACleanup();


    return   0;
}