Winsock编程基继承基础(网络对时程序)

#include <iostream>

#include <stdio.h>

#include "InitSock.h"

using namespace std;

void SetTimeFromTP(ULONG ulTime);

int main(void)

{

    CInitSock initSock;

    //创建套接字

    SOCKET s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);

    if (s == INVALID_SOCKET)

    {

        cout << "Failed socke()" << endl;

        return ;

    }

    //创建套接字之后如果首先sendto可以不绑定

    //若首先recvfrom则需要绑定

    //填写远程地址信息

    sockaddr_in addr;

    addr.sin_family = AF_INET;

    addr.sin_port = htons();

    addr.sin_addr.S_un.S_addr = inet_addr("129.6.15.28 "); //可在http://tf.nist.gov/service/time-servers.html得到IP

    //连接服务器

    if (connect(s, (sockaddr*)&addr, sizeof(addr)) == -)

    {

        cout << "Failed connect()" << endl;

        return ;

    }

    //等待接收时间协议返回的时间,学习Winsock I/O模型后最好使用异步I/O

    ULONG ulTime = ;

    int nRecv = recv(s, (char*)&ulTime, sizeof(ulTime), );

    if (nRecv > )

    {

        ulTime = ntohl(ulTime);

        SetTimeFromTP(ulTime);

        cout << "成功与服务器时间同步" << endl;

        cout << "接收到的数据: " << ulTime << endl;

    }

    else

    {

        cout << "服务器不能确认当前时间" << endl;

    }

    closesocket(s);

    getchar();

    return ;

}

void SetTimeFromTP(ULONG ulTime)

{

    //Windows文件时间是一个64位的值,是从1601年1月1日中午12:00到现在的时间间隔

    //单位是1/1000 0000秒即1000万分之1秒(100-nanosecond)

    FILETIME ft;

    SYSTEMTIME st;

    //首先将基准时间(1900.1.1.0.0.0.0)转换为windows文件时间

    st.wYear = ;

    st.wMonth = ;

    st.wDay = ;

    st.wHour = ;

    st.wMinute = ;

    st.wSecond = ;

    st.wMilliseconds = ;

    SystemTimeToFileTime(&st, &ft);

    //然后将Time Protocol使用基准时间加上已经逝去的时间即ulTime

    LONGLONG *pLLong = (LONGLONG*)&ft;

    //注意文件时间的单位

    *pLLong += (LONGLONG) * ulTime;

    //再将时间转换回来,更新系统时间

    FileTimeToSystemTime(&ft, &st);

    //SetSystemTime(&st);

    cout << st.wYear << "年"

        << st.wMonth << "月"

        << st.wDay << "日"

        << st.wHour + << "时"    //...

        << st.wMinute << "分"

        << st.wSecond << "秒" << endl;

}