[apple/libc.git] / gen / FreeBSD / clock.3

.\" Copyright (c) 1990, 1991, 1993
.\"	The Regents of the University of California.  All rights reserved.
.\"
.\" This code is derived from software contributed to Berkeley by
.\" the American National Standards Committee X3, on Information
.\" Processing Systems.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 4. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\"     @(#)clock.3	8.1 (Berkeley) 6/4/93
.\" $FreeBSD: src/lib/libc/gen/clock.3,v 1.12 2007/01/09 00:27:53 imp Exp $
.\"
.Dd June 4, 1993
.Dt CLOCK 3
.Os
.Sh NAME
.Nm clock
.Nd determine processor time used
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In time.h
.Ft clock_t
.Fn clock void
.Sh DESCRIPTION
The
.Fn clock
function
determines the amount of processor time used since the invocation of the
calling process, measured in
.Dv CLOCKS_PER_SEC Ns s
of a second.
.Sh RETURN VALUES
The
.Fn clock
function returns the amount of time used unless an error occurs, in which
case the return value is \-1.
.Sh SEE ALSO
.Xr getrusage 2 ,
.Xr clocks 7
.Sh STANDARDS
The
.Fn clock
function conforms to
.St -isoC
and
.St -susv3
which requires
.Dv CLOCKS_PER_SEC
to be defined as one million.
Commit	Line	Data
5b2abdfb	1	.\" Copyright (c) 1990, 1991, 1993
e9ce8d39 A	2	.\" The Regents of the University of California. All rights reserved.
e9ce8d39 A	3	.\"
5b2abdfb A	4	.\" This code is derived from software contributed to Berkeley by
	5	.\" the American National Standards Committee X3, on Information
	6	.\" Processing Systems.
	7	.\"
e9ce8d39 A	8	.\" Redistribution and use in source and binary forms, with or without
	9	.\" modification, are permitted provided that the following conditions
	10	.\" are met:
	11	.\" 1. Redistributions of source code must retain the above copyright
	12	.\" notice, this list of conditions and the following disclaimer.
	13	.\" 2. Redistributions in binary form must reproduce the above copyright
	14	.\" notice, this list of conditions and the following disclaimer in the
	15	.\" documentation and/or other materials provided with the distribution.
e9ce8d39 A	16	.\" 4. Neither the name of the University nor the names of its contributors
	17	.\" may be used to endorse or promote products derived from this software
	18	.\" without specific prior written permission.
	19	.\"
	20	.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	21	.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	22	.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	23	.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	24	.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	25	.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	26	.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	27	.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	28	.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	29	.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	30	.\" SUCH DAMAGE.
	31	.\"
5b2abdfb	32	.\" @(#)clock.3 8.1 (Berkeley) 6/4/93
1f2f436a	33	.\" $FreeBSD: src/lib/libc/gen/clock.3,v 1.12 2007/01/09 00:27:53 imp Exp $
e9ce8d39	34	.\"
5b2abdfb A	35	.Dd June 4, 1993
5b2abdfb A	36	.Dt CLOCK 3
e9ce8d39 A	37	.Os
e9ce8d39 A	38	.Sh NAME
5b2abdfb A	39	.Nm clock
5b2abdfb A	40	.Nd determine processor time used
e9ce8d39 A	41	.Sh LIBRARY
	42	.Lb libc
	43	.Sh SYNOPSIS
5b2abdfb A	44	.In time.h
	45	.Ft clock_t
	46	.Fn clock void
e9ce8d39 A	47	.Sh DESCRIPTION
e9ce8d39 A	48	The
5b2abdfb A	49	.Fn clock
	50	function
	51	determines the amount of processor time used since the invocation of the
	52	calling process, measured in
	53	.Dv CLOCKS_PER_SEC Ns s
	54	of a second.
e9ce8d39	55	.Sh RETURN VALUES
5b2abdfb A	56	The
	57	.Fn clock
	58	function returns the amount of time used unless an error occurs, in which
	59	case the return value is \-1.
e9ce8d39	60	.Sh SEE ALSO
5b2abdfb A	61	.Xr getrusage 2 ,
	62	.Xr clocks 7
	63	.Sh STANDARDS
e9ce8d39	64	The
5b2abdfb A	65	.Fn clock
5b2abdfb A	66	function conforms to
1f2f436a A	67	.St -isoC
	68	and
	69	.St -susv3
	70	which requires
5b2abdfb A	71	.Dv CLOCKS_PER_SEC
5b2abdfb A	72	to be defined as one million.