xref: /freebsd/lib/libc/gen/feature_present.3 (revision 39beb93c3f8bdbf72a61fda42300b5ebed7390c8)
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29.\" $FreeBSD$
30.\"
31.Dd January 8, 2008
32.Dt feature_present 3
33.Os
34.Sh NAME
35.Nm feature_present
36.Nd query presence of a kernel feature
37.Sh LIBRARY
38.Lb libc
39.Sh SYNOPSIS
40.In unistd.h
41.Ft int
42.Fn feature_present "const char *feature"
43.Sh DESCRIPTION
44The
45.Fn feature_present
46function provides a method for an application to determine if a specific
47kernel feature is present in the currently running kernel.
48The
49.Fa feature
50argument specifies the name of the feature to check.
51The
52.Fn feature_present
53function will return 1 if the specified feature is present,
54otherwise it will return 0.
55If the
56.Fn feature_present
57function is not able to determine the presence of
58.Fa feature
59due to an internal error it will return 0.
60.Sh RETURN VALUES
61If
62.Fa feature
63is present then 1 is returned;
64otherwise 0 is returned.
65.Sh SEE ALSO
66.Xr sysconf 3 ,
67.Xr sysctl 3
68.Sh HISTORY
69The
70.Fn feature_present
71function first appeared in
72.Fx 8.0 .
73