3winsock编程1

先看几个结构体定义

typedef struct WSAData {
  WORD wVersion;//版本号 通过MAKEWORD(2,2)返回该值 高位字节存储副版本号 第位字节存储主版本号
  WORD wHighVersion;//DLL可以支持的windows Socket规范的最高版本
  char szDescription[WSADESCRIPTION_LEN+1];//返回字符串 最多256字符
  char szSystemStatus[WSASYS_STATUS_LEN+1];//返回配置信息
  unsigned short iMaxSockets;
  unsigned short iMaxUdpDg;
  char FAR* lpVendorInfo;
} WSADATA, 
 *LPWSADATA;

#include <winsock2.h>
#pragma comment(lib, "ws2_32.lib")
#include <stdio.h>
int main(void)
{
    WSADATA wsaData;

    

    // Initialize Winsock version 2.2
    //成功返回0
    if (( WSAStartup(MAKEWORD(2, 2), &wsaData)) != 0)//调用WSAStartup初始化
    {
        // NOTE: Since Winsock failed to load we cannot use 
        // WSAGetLastError to determine the specific error for
        // why it failed. Instead we can rely on the return 
        // status of WSAStartup.

        printf("WSAStartup无法初始化");
        return 0;
    }

    // Setup Winsock communication code here 
    //显示wsadata的数据
    printf("version:%d.%d
", LOBYTE(wsaData.wVersion), HIBYTE(wsaData.wVersion));
    printf("High version: %d.%d
", LOBYTE(wsaData.wHighVersion), HIBYTE(wsaData.wHighVersion));
    printf("Desription:%s
", wsaData.szDescription);
    printf("System Status:%s", wsaData.szSystemStatus);
    // When your application is finished call WSACleanup
    if (WSACleanup() == SOCKET_ERROR)
    {
        printf("WSACleanup出错%d", WSAGetLastError());//返回错误代码
        printf("

");
        system("pause");
        
    }
    getchar();

    
}

注意：引入静态库哦