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Revision 1.16, Sat Nov 5 18:17:29 2011 UTC (3 years ago) by christos
Branch: MAIN
CVS Tags: yamt-pagecache-base9, yamt-pagecache-base8, yamt-pagecache-base7, yamt-pagecache-base6, yamt-pagecache-base5, yamt-pagecache-base4, yamt-pagecache-base3, yamt-pagecache-base2, tls-maxphys-base, tls-maxphys, tls-earlyentropy-base, tls-earlyentropy, riastradh-xf86-video-intel-2-7-1-pre-2-21-15, riastradh-drm2-base3, riastradh-drm2-base2, riastradh-drm2-base1, riastradh-drm2-base, riastradh-drm2, netbsd-7-base, netbsd-7, netbsd-6-base, netbsd-6-1-RELEASE, netbsd-6-1-RC4, netbsd-6-1-RC3, netbsd-6-1-RC2, netbsd-6-1-RC1, netbsd-6-1-5-RELEASE, netbsd-6-1-4-RELEASE, netbsd-6-1-3-RELEASE, netbsd-6-1-2-RELEASE, netbsd-6-1-1-RELEASE, netbsd-6-1, netbsd-6-0-RELEASE, netbsd-6-0-RC2, netbsd-6-0-RC1, netbsd-6-0-6-RELEASE, netbsd-6-0-5-RELEASE, netbsd-6-0-4-RELEASE, netbsd-6-0-3-RELEASE, netbsd-6-0-2-RELEASE, netbsd-6-0-1-RELEASE, netbsd-6-0, netbsd-6, matt-nb6-plus-nbase, matt-nb6-plus-base, matt-nb6-plus, agc-symver-base, agc-symver, HEAD
Changes since 1.15: +3 -8 lines

there no errors defined for time.

.\"	$NetBSD: time.3,v 1.16 2011/11/05 18:17:29 christos Exp $
.\"
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.\"     @(#)time.3	8.1 (Berkeley) 6/4/93
.\"
.Dd November 5, 2011
.Dt TIME 3
.Os
.Sh NAME
.Nm time
.Nd get time of day
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In time.h
.Ft time_t
.Fn time "time_t *tloc"
.Sh DESCRIPTION
The
.Fn time
function
returns the value of time in seconds since 0 hours, 0 minutes,
0 seconds, January 1, 1970, Coordinated Universal Time.
.Pp
A copy of the time value may be saved to the area indicated by the
pointer
.Fa tloc .
If
.Fa tloc
is a
.Dv NULL
pointer, no value is stored.
.Pp
Upon successful completion,
.Fn time
returns the value of time.
Otherwise a value of
.Po
.Po Fa time_t Pc \-1
.Pc
is returned and the global variable
.Va errno
is set to indicate the error.
.Sh ERRORS
No errors are defined.
.Sh SEE ALSO
.Xr gettimeofday 2 ,
.Xr ctime 3
.Sh STANDARDS
The
.Fn time
function conforms to
.St -p1003.1-90 .
.Sh HISTORY
A
.Fn time
function appeared in
.At v2 .
It returned a 32-bit value measuring sixtieths of a second, leading to
rollover every 2.26 years.
In
.At v6 ,
the precision of
.Fn time
was changed to seconds, allowing 135.6 years between rollovers.
.Pp
In
.Nx 6.0
the
.Vt 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
.Vt time_t
is the same as
.Vt long
will fail on 32-bit machines in 2038.