time(3) [netbsd man page]

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

time(3) 						     Library Functions Manual							   time(3)

NAME

       time, time64, TIMET32TO64, TIMET64TO32 - Gets time, converts time between time_t and time64_t

LIBRARY

       Standard C Library (libc.so, libc.a)

SYNOPSIS

       #include <time.h>

       time_t time(
	       time_t *tloc);

       The following data type, function declaration and macros are Compaq extensions and do not conform to current standards.	These features are
       provided to support the time64_t data type and are accessible only when the _TIME64_T feature macro is defined during compilation.

       #include <time.h>

       typedef long time64_t;

       time64_t time64(
	       time64_t *tloc64);

       void TIMET32TO64(t32, t64)

       int TIMET64TO32(t64, t32)

PARAMETERS

       Points to the location where the return value of type time_t is stored. When this parameter is a null pointer, no value is stored.   Points
       to  the location where the return value of type time64_t is stored. When this parameter is a null pointer, no value is stored.  Refers to a
       variable of type time_t.  Refers to a variable of type time64_t.

DESCRIPTION

       The time() function returns the time in seconds since the Epoch. The Epoch is referenced to 00:00:00 CUT (Coordinated Universal Time) 1 Jan
       1970.

       The  time64_t  data  type  is  a  64-bit signed value which, like the 32-bit time_t data type, is defined as the "time in seconds since the
       Epoch."	It is provided for storage and manipulation of times beyond the range of a 32-bit time_t (Dec 13 20:45:52 GMT 1901 through Jan	19
       03:14:07 GMT 2038).  This data type is only available when the _TIME64_T feature macro is defined during compilation.

       The time64() function works exactly as the time() function, but uses the larger time64_t type (referenced by the tloc64 pointer) instead of
       time_t.	The current system time setting limits (Jan 1 00:00:00 GMT 1970 through Jan 19 03:14:07 GMT 2038) are not changed by this function
       or the time64_t data type.  This function declaration is only available when the _TIME64_T feature macro is defined during compilation.

       The  TIMET32TO64()  and	TIMET64TO32() macros are provided to assist developers converting between values of type time_t and values of type
       time64_t.  The TIMET32TO64() macro converts the value contained in t32 to a value of type time64_t and stores the result in t64, performing
       sign-extension  as  appropriate.  The TIMET64TO32() macro attempts to convert the value contained in t64 to a value of type time_t, storing
       the result in t32. If the value of t64 overflows the size of a time_t, the value of the TIMET64TO32() macro will be 1 and the value of  t32
       is undefined. Otherwise, the value of the TIMET64TO32() macro will be 0 and t32 will contain the converted value from t64. These conversion
       macros are only available when the _TIME64_T feature macro is defined during compilation.

RETURN VALUES

       Upon successful completion, the time() function returns the value of time in seconds since the Epoch.  Otherwise, the value  (time_t)-1	is
       returned.

       Upon  successful completion, the time64() function returns the value of time in seconds since the Epoch.  Otherwise, the value (time64_t)-1
       is returned.

RELATED INFORMATION

       Functions: gettimeofday(2), clock(3), ctime(3), difftime(3), stime(3), strftime(3), strptime(3)

       Standards: standards(5) delim off

																	   time(3)