[Discussion] POSIX, the Love of Backticks and All That Jazz Post: 302990351

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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 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

       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.

CONFORMING TO

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

NOTES

       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  syn-
       chronized  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

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

COLOPHON

       This page is part of release 3.44 of the Linux man-pages project.  A description of the project, and information about reporting bugs,  can
       be found at http://www.kernel.org/doc/man-pages/.

Linux								    2011-09-09								   TIME(2)