redhat man page for time

TIME(2) 						     Linux Programmer's Manual							   TIME(2)

NAME
       time - get time in seconds

SYNOPSIS
       #include <time.h>

       time_t time(time_t *t);

DESCRIPTION
       time returns the time since the Epoch (00:00:00 UTC, January 1, 1970), measured in seconds.

       If t is non-NULL, the return value is also stored in the memory pointed to by t.

RETURN VALUE
       On success, the value of time in seconds since the Epoch is returned.  On error, ((time_t)-1) is returned, and errno is set appropriately.

ERRORS
       EFAULT t points outside your accessible address space.

NOTES
       POSIX.1	defines  seconds  since  the  Epoch  as a value to be interpreted as the number of seconds between a specified time and the Epoch,
       according to a formula for conversion from UTC equivalent to conversion on the naive basis that leap seconds  are  ignored  and	all  years
       divisible  by 4 are leap years.	This value is not the same as the actual number of seconds between the time and the Epoch, because of leap
       seconds and because clocks are not required to be synchronised to a standard reference.	The intention is that the interpretation  of  sec-
       onds since the Epoch values be consistent; see POSIX.1 Annex B 2.2.2 for further rationale.

CONFORMING TO
       SVr4, SVID, POSIX, X/OPEN, BSD 4.3
       Under BSD 4.3, this call is obsoleted by gettimeofday(2).  POSIX does not specify any error conditions.

SEE ALSO
       ctime(3), date(1), ftime(3), gettimeofday(2)

Linux 2.0.30							    1997-09-09								   TIME(2)