mktime(), asctime(), gmtime(), localtime(), strftime()
#include time.h>
=.35 struct tm int tm_sec;seconds (0…59) int tm_min;minutes (0…59) int tm_hour;hours (0…23) int tm_mday;day of month (1…31) int tm_mon;month (0…11) int tm_year;year - 1900 int tm_wday;day of week (0=Sun…6=Sat) int tm_yday;day of year (0…365) int tm_isdst;daylight savings