xref: /freebsd/lib/libc/gen/feature_present.3 (revision a6d11f7139f1379415d6ac544c8ff778059622e6)
1ce309a2fSJohn Baldwin.\" Copyright (c) 2008 Yahoo!, Inc.
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3ce309a2fSJohn Baldwin.\" Written by: John Baldwin <jhb@FreeBSD.org>
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29ce309a2fSJohn Baldwin.\" $FreeBSD$
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31ce309a2fSJohn Baldwin.Dd January 8, 2008
32*a6d11f71SRuslan Ermilov.Dt FEATURE_PRESENT 3
33ce309a2fSJohn Baldwin.Os
34ce309a2fSJohn Baldwin.Sh NAME
35ce309a2fSJohn Baldwin.Nm feature_present
36ce309a2fSJohn Baldwin.Nd query presence of a kernel feature
37ce309a2fSJohn Baldwin.Sh LIBRARY
38ce309a2fSJohn Baldwin.Lb libc
39ce309a2fSJohn Baldwin.Sh SYNOPSIS
40ce309a2fSJohn Baldwin.In unistd.h
41ce309a2fSJohn Baldwin.Ft int
42ce309a2fSJohn Baldwin.Fn feature_present "const char *feature"
43ce309a2fSJohn Baldwin.Sh DESCRIPTION
44ce309a2fSJohn BaldwinThe
45ce309a2fSJohn Baldwin.Fn feature_present
46ce309a2fSJohn Baldwinfunction provides a method for an application to determine if a specific
47ce309a2fSJohn Baldwinkernel feature is present in the currently running kernel.
48ce309a2fSJohn BaldwinThe
49ce309a2fSJohn Baldwin.Fa feature
50ce309a2fSJohn Baldwinargument specifies the name of the feature to check.
51ce309a2fSJohn BaldwinThe
52ce309a2fSJohn Baldwin.Fn feature_present
53ce309a2fSJohn Baldwinfunction will return 1 if the specified feature is present,
54ce309a2fSJohn Baldwinotherwise it will return 0.
55ce309a2fSJohn BaldwinIf the
56ce309a2fSJohn Baldwin.Fn feature_present
57ce309a2fSJohn Baldwinfunction is not able to determine the presence of
58ce309a2fSJohn Baldwin.Fa feature
59ce309a2fSJohn Baldwindue to an internal error it will return 0.
60ce309a2fSJohn Baldwin.Sh RETURN VALUES
61ce309a2fSJohn BaldwinIf
62ce309a2fSJohn Baldwin.Fa feature
63ce309a2fSJohn Baldwinis present then 1 is returned;
64ce309a2fSJohn Baldwinotherwise 0 is returned.
65ce309a2fSJohn Baldwin.Sh SEE ALSO
66ce309a2fSJohn Baldwin.Xr sysconf 3 ,
67ce309a2fSJohn Baldwin.Xr sysctl 3
68ce309a2fSJohn Baldwin.Sh HISTORY
69ce309a2fSJohn BaldwinThe
70ce309a2fSJohn Baldwin.Fn feature_present
71ce309a2fSJohn Baldwinfunction first appeared in
72ce309a2fSJohn Baldwin.Fx 8.0 .
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