我需要一种方法在每次更新列表时插入当前日期-时间。 简单地说，这似乎很有效。

#include<bits/stdc++.h>
#include<unistd.h>
using namespace std;
int main()
{   //initialize variables
    time_t now; 
    //blah..blah
    /*each time I want the updated stamp*/
    now=time(0);cout<<ctime(&now)<<"blah_blah";
}

c++标准库没有提供合适的日期类型。c++继承了C语言中用于日期和时间操作的结构和函数，以及一些考虑本地化的日期/时间输入和输出函数。

// Current date/time based on current system
time_t now = time(0);

// Convert now to tm struct for local timezone
tm* localtm = localtime(&now);
cout << "The local date and time is: " << asctime(localtm) << endl;

// Convert now to tm struct for UTC
tm* gmtm = gmtime(&now);
if (gmtm != NULL) {
cout << "The UTC date and time is: " << asctime(gmtm) << endl;
}
else {
cerr << "Failed to get the UTC date and time" << endl;
return EXIT_FAILURE;
}

localtime_s()版本:

#include <stdio.h>
#include <time.h>

int main ()
{
  time_t current_time;
  struct tm  local_time;

  time ( &current_time );
  localtime_s(&local_time, &current_time);

  int Year   = local_time.tm_year + 1900;
  int Month  = local_time.tm_mon + 1;
  int Day    = local_time.tm_mday;

  int Hour   = local_time.tm_hour;
  int Min    = local_time.tm_min;
  int Sec    = local_time.tm_sec;

  return 0;
} 

#include <iostream>
#include <chrono>
#include <string>
#pragma warning(disable: 4996)
// Ver: C++ 17 
// IDE: Visual Studio
int main() {
    using namespace std; 
    using namespace chrono;
    time_point tp = system_clock::now();
    time_t tt = system_clock::to_time_t(tp);
    cout << "Current time: " << ctime(&tt) << endl;
    return 0;
}

c++与C共享它的日期/时间函数。tm结构可能是c++程序员最容易使用的结构——下面打印今天的日期:

#include <ctime>
#include <iostream>

int main() {
    std::time_t t = std::time(0);   // get time now
    std::tm* now = std::localtime(&t);
    std::cout << (now->tm_year + 1900) << '-' 
         << (now->tm_mon + 1) << '-'
         <<  now->tm_mday
         << "\n";
}

你也可以直接使用ctime():

#include <stdio.h>
#include <time.h>

int main ()
{
  time_t rawtime;
  struct tm * timeinfo;

  time ( &rawtime );
  printf ( "Current local time and date: %s", ctime (&rawtime) );

  return 0;
}