typedef struct {
   int tm_hour;   /* hour (0 - 23) */
   int tm_isdst;  /* daylight saving time enabled/disabled */
   int tm_mday;   /* day of month (1 - 31) */
   int tm_min;    /* minutes (0 - 59) */
   int tm_mon;    /* month (0 - 11 : 0 = January) */
   int tm_sec;    /* seconds (0 - 59) */
   int tm_wday;   /* Day of week (0 - 6 : 0 = Sunday) */
   int tm_yday;   /* Day of year (0 - 365) */
   int tm_year;   /* Year less 1900 */
}

Portability.
  Defined in ANSI-C.

See also.
  asctime, gmtime, localtime, mktime