xref: /freebsd/lib/libc/gen/clock_getcpuclockid.3 (revision e0c4386e7e71d93b0edc0c8fa156263fc4a8b0b6)
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
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35.Dd August 21, 2012
36.Dt CLOCK_GETCPUCLOCKID 3
37.Os
38.Sh NAME
39.Nm clock_getcpuclockid
40.Nd access a process CPU-time clock
41.Sh LIBRARY
42.Lb libc
43.Sh SYNOPSIS
44.In time.h
45.Ft int
46.Fn clock_getcpuclockid "pid_t pid" "clockid_t *clock_id"
47.Sh DESCRIPTION
48The
49.Fn clock_getcpuclockid
50returns the clock ID of the CPU-time clock of the process specified by
51.Fa pid .
52If the process described by
53.Fa pid
54exists and the calling process has permission, the clock ID of this
55clock will be returned in
56.Fa clock_id .
57.Pp
58If
59.Fa pid
60is zero, the
61.Fn clock_getcpuclockid
62function returns the clock ID of the CPU-time clock of the process
63making the call, in
64.Fa clock_id .
65.Sh RETURN VALUES
66Upon successful completion,
67.Fn clock_getcpuclockid
68returns zero; otherwise, an error number is returned to indicate the
69error.
70.Sh ERRORS
71The
72.Fn clock_getcpuclockid
73function will fail if:
74.Bl -tag -width Er
75.It Bq Er EPERM
76The requesting process does not have permission to access the CPU-time
77clock for the process.
78.It Bq Er ESRCH
79No process can be found corresponding to the process specified by
80.Fa pid .
81.El
82.Sh SEE ALSO
83.Xr clock_gettime 2
84.Sh STANDARDS
85The
86.Fn clock_getcpuclockid
87function conforms to
88.St -p1003.1-2001 .
89.Sh HISTORY
90The
91.Fn clock_getcpuclockid
92function first appeared in
93.Fx 10.0 .
94.Sh AUTHORS
95.An David Xu Aq Mt davidxu@FreeBSD.org
96