gmtime - Convert Time

Syntax

#include <time.h>
struct tm *gmtime(const time_t *time);

The gmtime function breaks down the time value and stores it in a tm structure, defined in time.h. The structure pointed to by the return value reflects Coordinated Universal Time, not local time. The value time is usually obtained from a call to time.

The fields of the tm structure include: compact break=fit.

tm_sec

Seconds (0-61)

Minutes (0-59)

Hours (0-23)

Day of month (1-31)

Month (0-11; January = 0)

Year (current year minus 1900)

Day of week (0-6; Sunday = 0)

Day of year (0-365; January 1 = 0)

Zero if Daylight Saving Time is not in effect; positive if Daylight Saving Time is in effect; negative if the information is not available.

gmtime returns a pointer to the resulting tm structure. It returns NULL if Coordinated Universal Time is not available.

Note:

The range (0-61) for tm_sec allows for as many as two leap seconds.
The gmtime and localtime functions may use a common, statically allocated buffer for the conversion. Each call to one of these functions may alter the result of the previous call.
The time and date functions begin at 00:00:00 Coordinated Universal Time, January 1, 1970.

This example uses gmtime to adjust a time_t representation to a Coordinated Universal Time character string, and then converts it to a printable string using asctime.

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

int main(void)
{
   time_t ltime;

   time(&ltime);
   printf("Coordinated Universal Time is %s\n", asctime(gmtime(&ltime)));
   return 0;

   /****************************************************************************
      The output should be similar to:

      Coordinated Universal Time is Mon Sep 16 21:44 1995
   ****************************************************************************/
}

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