Converts a time value to a structure.

#include <time.h>

struct tm *gmtime (const time_t *timer);

struct tm *_gmtime32(const __time32_t *timer);
struct tm *_gmtime64(const __time64_t *timer);

struct tm *gmtime_s(const time_t *timer, struct tm *result);
struct tm *_gmtime32_s(const __time32_t *timer, struct tm *result);
struct tm *_gmtime64_s(const __time64_t *timer, struct tm *result);

Parameters

timer

Pointer to stored time, which represents the seconds elapsed since epoch time (1 January 1970), in UTC. This value is usually obtained from a call to time().

result

Pointer to tm structure. The fields of the returned structure hold the evalated value of the timer argument in UTC.

Remarks

gmtime breaks down the timer value and stores it in at TM. The structure result reflects GMT, not local time.

gmtime, mktime, and localtime use a single statically allocated structure to hold the result. Subsequent calls to these functions destroy the result of any previous call.

gmtime_s is a secure version of gmtime where a buffer to receive the result may be passed to the call.

gmtime() is a wrapper for _gmtime32() and time_t is, by default, equivalent to __time32_t. If you need to force the compiler to interpret time_t as the new 64-bit __time64_t, you can define _USE_64BIT_TIME_T. This is recommended to ensure that your application does not fail after January 18, 2038, but is not backwards-compatible with previous versions of INtime.

Similarly, gmtime_s() is a wrapper for _gmtime32_s unless _USE_64BIT_TIME_T is defined, when it is a wrapper for _gmtime64_s.

Return Values

A pointer to the TM structure.

Requirements

See Also

mktime, localtime, asctime, time, TIME.H for description of TM structure