1.\"	$OpenBSD: clock_getcpuclockid.3,v 1.3 2015/01/15 19:26:27 schwarze Exp $
2.\"
3.\" Copyright (c) 2013 Philip Guenther <guenther@openbsd.org>
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17.Dd $Mdocdate: January 15 2015 $
18.Dt CLOCK_GETCPUCLOCKID 3
19.Os
20.Sh NAME
21.Nm clock_getcpuclockid
22.Nd get a clock measuring process CPU time
23.Sh SYNOPSIS
24.In time.h
25.Ft int
26.Fn clock_getcpuclockid "pid_t pid" "clockid_t *clock_id"
27.Sh DESCRIPTION
28The
29.Fn clock_getcpuclockid
30function allows the calling process to get a
31.Vt clockid_t
32value that measures the time spent by CPUs running in user or kernel mode
33on behalf of the process specified by
34.Fa pid .
35If
36.Fa pid
37is zero, then a clock for the calling process will be returned.
38.Sh RETURN VALUES
39If successful,
40.Fn clock_getcpuclockid
41will return zero.
42Otherwise an error number will be returned to indicate the error.
43.Sh ERRORS
44.Fn clock_getcpuclockid
45will fail if:
46.Bl -tag -width Er
47.It Bq Er EPERM
48.Fa pid
49is neither zero nor the PID of the calling process.
50.El
51.Sh SEE ALSO
52.Xr clock_gettime 2 ,
53.Xr pthread_getcpuclockid 3
54.Sh STANDARDS
55The
56.Fn clock_getcpuclockid
57function conforms to
58.St -p1003.1-2008 .
59.Sh HISTORY
60The
61.Fn clock_getcpuclockid
62function first appeared in IEEE Std 1003.1d-1999
63.Pq Dq POSIX.1d
64and has been available since
65.Ox 5.4 .
66