Returning Actual Seconds

I'm trying to code a small program that acts as a 'quasi' timer.

In the middle of the screen I need the Time HH:MM:SS
to be refreshed every second. Starting at 00:00:00.

Any ideas on where to begin ?
Or does anyone have some sample code
they wouldn't mind sharing.

..This Program is out of Curiosity..

Code:

---

#include <iostream>
using std::cout;

#include <unistd.h>

int main ()
{
    int sec = 0;
 
    while (1) {
        cout << sec++ << '\r';
        sleep (1);
    }
 
    return 0;
}

---

that's one easy way to count seconds. i'm sure there's a way to sleep with windows. i just can't remeber the header file. that should get your started, right?