xref: /freebsd/lib/libkvm/kvm_getcptime.3 (revision 7899f917b1c0ea178f1d2be0cfb452086d079d23)
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29.Dd August 19, 2008
30.Dt KVM_GETCPTIME 3
31.Os
32.Sh NAME
33.Nm kvm_getcptime
34.Nd fetch global CPU time statistics
35.Sh LIBRARY
36.Lb libkvm
37.Sh SYNOPSIS
38.In sys/param.h
39.In sys/resource.h
40.In sys/sysctl.h
41.In kvm.h
42.Ft int
43.Fn kvm_getcptime "kvm_t *kd" "long *cp_time"
44.Sh DESCRIPTION
45The
46.Fn kvm_getcptime
47function stores the global CPU time statistics from the kernel
48.Fa kd
49in the array of counters pointed to by
50.Fa cp_time .
51Note that
52.Fa cp_time
53should point to an array of
54.Dv CPUSTATES
55long integers.
56The format of the counters is identical to that output by the
57.Va kern.cp_time
58sysctl.
59.Sh CACHING
60This function caches the nlist values for various kernel variables which it
61reuses in successive calls.
62You may call the function with
63.Fa kd
64set to
65.Dv NULL
66to clear this cache.
67.Sh RETURN VALUES
68The
69.Nm kvm_getcptime
70function returns 0 on success and -1 on failure.
71If an error occurs,
72then an error message may be retrieved via
73.Xr kvm_geterr 3 .
74.Sh SEE ALSO
75.Xr kvm 3
76