c++获取系统时间

#include<ctime>
#include<sstream>
#include<iostream>

using namespace std;

int main() {
    time_t now = time(NULL);
    tm* t = localtime(&now);

    // 将信息输出到字符串流
    stringstream ss;
    ss << t->tm_year + 1900 << "." << t->tm_mon + 1 << "." <<
        t->tm_mday << ".." << t->tm_hour << "." << t->tm_min << "." << t->tm_sec;
    cout << "写入的文件为: " << ss.str() << endl;//字符串类型
    return 0;
}

代码来源：C++获取系统的时间 并转化为字符串_今晚看星星的博客