freebsd-skq/lib/libc/gen/timespec_get.3
Warner Losh 3d19db5dfb Update man page to include FreeBSD-specific details.
While this implements a standards-conforming C11 function, there's
implementation details the programmer needs to know. Include those
here. Make changes inspired by comments on the initial review as well,
though mostly this involves stealing the epoch verbage from
gettimeofday(2). Add myself to authors since I've now changed a
substantial amount of this man page.
2018-08-10 15:16:41 +00:00

87 lines
2.5 KiB
Groff

.\" $NetBSD: timespec_get.3,v 1.2 2016/10/04 10:46:40 wiz Exp $
.\"
.\" Copyright (c) 2016 The NetBSD Foundation, Inc.
.\" All rights reserved.
.\"
.\" This code is derived from software contributed to The NetBSD Foundation
.\" by Kamil Rytarowski.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
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.\" notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
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.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
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.\" $FreeBSD$
.\"
.Dd August 10, 2018
.Dt TIMESPEC_GET 3
.Os
.Sh NAME
.Nm timespec_get
.Nd get current calendar time
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In time.h
.Ft int
.Fn timespec_get "struct timespec *ts" "int base"
.Sh DESCRIPTION
The
.Nm
function sets the interval pointed to by
.Fa ts
to hold the current calendar time based on the specified time base in
.Fa base .
.Pp
The base
.Dv TIME_UTC
returns the time since the epoch.
This time is expressed in seconds and nanoseconds since midnight (0 hour), January 1, 1970.
In
.Fx ,
this corresponds to
.Dv CLOCK_REALTIME .
.Sh RETURN VALUES
The
.Nm
function returns the passed value of
.Fa base
if successful, otherwise
.Dv 0
on failure.
.Sh SEE ALSO
.Xr gettimeofday 2 ,
.Xr clock_gettime 2 ,
.Xr time 3
.Sh STANDARDS
The
.Nm
function with a
.Fa base
of
.Dv TIME_UTC
conforms to
.St -isoC-2011 .
.Sh HISTORY
This interface first appeared in
.Fx 12 .
.Sh AUTHORS
.An Kamil Rytarowski Aq Mt kamil@NetBSD.org
.An Warner Losh Aq Mt imp@FreeBSD.org