Time, Date, and Localization Functions
The time and date functions are defined in the header time.h.
This header defines three time-related types:
time_t represent the system time and date.
This is called the calendar time.
tm structure contains the following members:
int tm_sec; /* seconds, 0-60 */ int tm_min; /* minutes, 0-59 */ int tm_hour; /* hours, 0-23 */ int tm_mday; /* day of the month, 1-31 */ int tm_mon; /* months since Jan, 0-11 */ int tm_year; /* years from 1900 */ int tm_wday; /* days since Sunday, 0-6 */ int tm_yday; /* days since Jan 1, 0-365 */ int tm_isdst /* Daylight Saving Time indicator */
tm_isdst is positive during daylight saving time, zero if it not,
and negative if there is no information available.
This form of the time and date is called the broken-down time.
time.h defines the macro
is the number of system clock ticks per second.
The geopolitical environmental functions require the header
It defines the structure
is described under the function