Simplest way to show a clock in C++ and Linux

I'm using C++ under Linux compiling with standard GCC. In my program I wan开发者_运维问答t to add a simple clock showing HH:MM:SS. What's the easiest way to do that?

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You can make use of localtime along with strftime.

Working link

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A good way is to use localtime

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My quick-and-dirty solution:

// file now.cc
#include <iostream>
#include <iomanip>
#include <ctime>

using namespace std;

int main()
{
    time_t ct = time(0);
    struct tm* currtime = localtime(&ct);
    cout << setfill('0') << setw(2) << currtime->tm_hour << ":"
         << setw(2) << currtime->tm_min << ":"
         << setw(2) << currtime->tm_sec << endl;
    return 0;
}

This also does zero-padding (which you probably want).

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#include<stdio.h>
#include<stdlib.h>
#include<time.h>
void delay(unsigned int mseconds)
{
    clock_t goal = mseconds + clock();
    while (goal > clock());
}
int main()
{
    time_t myTime;

    while(1)
    {
        time(&myTime);
        printf("%s", asctime(gmtime(&myTime)));
        delay(1000);
        system("cls");
    }
    return 0;
}

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The easiest way?

system("date +%T");

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Look at getTimeStamp() you can adjust this to any format you want