xref: /freebsd/lib/libkvm/kvm_getcptime.3 (revision b740c88bfb6453416926271c089262e7164dace3)
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29.\" $FreeBSD$
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31.Dd August 19, 2008
32.Dt KVM_GETCPTIME 3
33.Os
34.Sh NAME
35.Nm kvm_getcptime
36.Nd fetch global CPU time statistics
37.Sh LIBRARY
38.Lb libkvm
39.Sh SYNOPSIS
40.In sys/param.h
41.In sys/resource.h
42.In sys/sysctl.h
43.In kvm.h
44.Ft int
45.Fn kvm_getcptime "kvm_t *kd" "long *cp_time"
46.Sh DESCRIPTION
47The
48.Fn kvm_getcptime
49function stores the global CPU time statistics from the kernel
50.Fa kd
51in the array of counters pointed to by
52.Fa cp_time .
53Note that
54.Fa cp_time
55should point to an array of
56.Dv CPUSTATES
57long integers.
58The format of the counters is identical to that output by the
59.Va kern.cp_time
60sysctl.
61.Sh CACHING
62This function caches the nlist values for various kernel variables which it
63reuses in successive calls.
64You may call the function with
65.Fa kd
66set to
67.Dv NULL
68to clear this cache.
69.Sh RETURN VALUES
70The
71.Nm kvm_getcptime
72function returns 0 on success and -1 on failure.
73If an error occurs,
74then an error message may be retrieved via
75.Xr kvm_geterr 3 .
76.Sh SEE ALSO
77.Xr kvm 3
78