NAME
time —
get time of day
SYNOPSIS
#include
<time.h>
time_t
time(time_t
*now);
DESCRIPTION
The
time()
function returns the number of seconds elapsed since Jan 1 1970 00:00:00
UTC. This value is also written to now unless
now is NULL.
RETURN VALUES
The time() function is always successful,
and no return value is reserved to indicate an error.
SEE ALSO
STANDARDS
The time() function conforms to
IEEE Std 1003.1-2008 (“POSIX.1”).
HISTORY
A time() system call first appeared in
Version 1 AT&T UNIX. That version counted
time in sixtieths of a second with a 32-bit return value, ensuring an
integer overflow crisis every 2.26 years. In
Version 6 AT&T UNIX the granularity of
the return value was reduced to whole seconds, delaying the aforementioned
crisis until 2038. In 4.1cBSD the function was moved
out of the kernel into the C standard library and reimplemented with
gettimeofday(2).