[Discussion] POSIX, the Love of Backticks and All That Jazz Post: 302990486

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LEARN ABOUT NETBSD

time

TIME(3) 						   BSD Library Functions Manual 						   TIME(3)

NAME

     time -- get time of day

LIBRARY

     Standard C Library (libc, -lc)

SYNOPSIS

     #include <time.h>

     time_t
     time(time_t *tloc);

DESCRIPTION

     The time() function returns the value of time in seconds since 0 hours, 0 minutes, 0 seconds, January 1, 1970, Coordinated Universal Time.

     A copy of the time value may be saved to the area indicated by the pointer tloc.  If tloc is a NULL pointer, no value is stored.

     Upon successful completion, time() returns the value of time.  Otherwise a value of ((time_t) -1) is returned and the global variable errno
     is set to indicate the error.

ERRORS

     No errors are defined.

SEE ALSO

     gettimeofday(2), ctime(3)

STANDARDS

     The time() function conforms to ISO/IEC 9945-1:1990 (``POSIX.1'').

HISTORY

     A time() function appeared in Version 2 AT&T UNIX.  It returned a 32-bit value measuring sixtieths of a second, leading to rollover every
     2.26 years.  In Version 6 AT&T UNIX, the precision of time() was changed to seconds, allowing 135.6 years between rollovers.

     In NetBSD 6.0 the time_t type was changed to be 64 bits wide, including on 32-bit machines, making rollover a concern for the far distant
     future only.  Note however that any code making the incorrect assumption that time_t is the same as long will fail on 32-bit machines in
     2038.

BSD
								 November 5, 2011							       BSD