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

NAME         top

       time - get time in seconds

SYNOPSIS         top

       #include <time.h>

       time_t time(time_t *t);

DESCRIPTION         top

       time() returns the time as the number of seconds since the Epoch,
       1970-01-01 00:00:00 +0000 (UTC).

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

RETURN VALUE         top

       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         top

       EFAULT t points outside your accessible address space.

CONFORMING TO         top

       SVr4, 4.3BSD, C89, C99, POSIX.1-2001.  POSIX does not specify any
       error conditions.

NOTES         top

       POSIX.1 defines seconds since the Epoch using a formula that
       approximates the number of seconds between a specified time and the
       Epoch.  This formula takes account of the facts that all years that
       are evenly divisible by 4 are leap years, but years that are evenly
       divisible by 100 are not leap years unless they are also evenly
       divisible by 400, in which case they 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 system clocks are not
       required to be synchronized to a standard reference.  The intention
       is that the interpretation of seconds since the Epoch values be
       consistent; see POSIX.1-2008 Rationale A.4.15 for further rationale.

SEE ALSO         top

       date(1), gettimeofday(2), ctime(3), ftime(3), time(7)

COLOPHON         top

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Linux                            2011-09-09                          TIME(2)