C Reference function gmtime()

Usage of gmtime():

struct tm * gmtime ( const time_t * ptr_time);

Parameters:

The pointer ptr_time is a pointer to a time_t object that contains a calendar time.
Calendar time is the number of seconds that have elapsed since EPOCH, which is 00:00:00, January 1, 1970 Universal Coordinate Time (UTC)

Return Value:

The function gmtime() returns a pointer to a tm structure. The tm structure contains the time information.

Explanation:

The tm structure is statically allocated and shared by the functions gmtime and localtime.
If either one of these functions is called, then the content of the structure tm is overwritten.

Source code example of gmtime():

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

int main(void)
{
	time_t time_raw_format;
	time(&time_raw_format);
	printf ("Coordinated Universal Time is %s\n",
		asctime(gmtime(&time_raw_format)));
	return 0;
}

Output example of the program above:

	Coordinated Universal Time is Fri Jan 11 12:11:50 2008