xref: /freebsd/lib/libc/gen/clock_getcpuclockid.3 (revision 8ddb146abcdf061be9f2c0db7e391697dafad85c)
1.\" Copyright (c) 2012 David Xu <davidxu@FreeBSD.org>
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25.\" Portions of this text are reprinted and reproduced in electronic form
26.\" from IEEE Std 1003.1, 2004 Edition, Standard for Information Technology --
27.\" Portable Operating System Interface (POSIX), The Open Group Base
28.\" Specifications Issue 6, Copyright (C) 2001-2004 by the Institute of
29.\" Electrical and Electronics Engineers, Inc and The Open Group.  In the
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35.\" $FreeBSD$
36.\"
37.Dd August 21, 2012
38.Dt CLOCK_GETCPUCLOCKID 3
39.Os
40.Sh NAME
41.Nm clock_getcpuclockid
42.Nd access a process CPU-time clock
43.Sh LIBRARY
44.Lb libc
45.Sh SYNOPSIS
46.In time.h
47.Ft int
48.Fn clock_getcpuclockid "pid_t pid" "clockid_t *clock_id"
49.Sh DESCRIPTION
50The
51.Fn clock_getcpuclockid
52returns the clock ID of the CPU-time clock of the process specified by
53.Fa pid .
54If the process described by
55.Fa pid
56exists and the calling process has permission, the clock ID of this
57clock will be returned in
58.Fa clock_id .
59.Pp
60If
61.Fa pid
62is zero, the
63.Fn clock_getcpuclockid
64function returns the clock ID of the CPU-time clock of the process
65making the call, in
66.Fa clock_id .
67.Sh RETURN VALUES
68Upon successful completion,
69.Fn clock_getcpuclockid
70returns zero; otherwise, an error number is returned to indicate the
71error.
72.Sh ERRORS
73The
74.Fn clock_getcpuclockid
75function will fail if:
76.Bl -tag -width Er
77.It Bq Er EPERM
78The requesting process does not have permission to access the CPU-time
79clock for the process.
80.It Bq Er ESRCH
81No process can be found corresponding to the process specified by
82.Fa pid .
83.El
84.Sh SEE ALSO
85.Xr clock_gettime 2
86.Sh STANDARDS
87The
88.Fn clock_getcpuclockid
89function conforms to
90.St -p1003.1-2001 .
91.Sh HISTORY
92The
93.Fn clock_getcpuclockid
94function first appeared in
95.Fx 10.0 .
96.Sh AUTHORS
97.An David Xu Aq Mt davidxu@FreeBSD.org
98