#include <sys/time.h>int gettimeofday(struct timeval
tp, void *reserved);
int settimeofday(struct timeval
tp, void *reserved);
settimeofday- set date and time
gettimeofday gets and settimeofday sets the system's notion of the current time. The current time is expressed in elapsed seconds and microseconds since 00:00 Universal Coordinated Time, January 1, 1970. The resolution of the system clock is hardware dependent; the time may be updated continuously or in clock ticks.
tp points to a timeval structure, which includes the following members:
long tv_sec; /seconds since Jan. 1, 1970
/ long tv_usec; /
and microseconds
/
If tp is a null pointer, the current time information is not returned or set.
The second argument to these functions, reserved, should be NULL.
The TZ environment variable holds time zone information. See timezone.
Only the privileged user may set the time of day.