xref: /freebsd/lib/libc/gen/feature_present.3 (revision fa9896e082a1046ff4fbc75fcba4d18d1f2efc19)
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.Dd January 8, 2008
30*a6d11f71SRuslan Ermilov.Dt FEATURE_PRESENT 3
31ce309a2fSJohn Baldwin.Os
32ce309a2fSJohn Baldwin.Sh NAME
33ce309a2fSJohn Baldwin.Nm feature_present
34ce309a2fSJohn Baldwin.Nd query presence of a kernel feature
35ce309a2fSJohn Baldwin.Sh LIBRARY
36ce309a2fSJohn Baldwin.Lb libc
37ce309a2fSJohn Baldwin.Sh SYNOPSIS
38ce309a2fSJohn Baldwin.In unistd.h
39ce309a2fSJohn Baldwin.Ft int
40ce309a2fSJohn Baldwin.Fn feature_present "const char *feature"
41ce309a2fSJohn Baldwin.Sh DESCRIPTION
42ce309a2fSJohn BaldwinThe
43ce309a2fSJohn Baldwin.Fn feature_present
44ce309a2fSJohn Baldwinfunction provides a method for an application to determine if a specific
45ce309a2fSJohn Baldwinkernel feature is present in the currently running kernel.
46ce309a2fSJohn BaldwinThe
47ce309a2fSJohn Baldwin.Fa feature
48ce309a2fSJohn Baldwinargument specifies the name of the feature to check.
49ce309a2fSJohn BaldwinThe
50ce309a2fSJohn Baldwin.Fn feature_present
51ce309a2fSJohn Baldwinfunction will return 1 if the specified feature is present,
52ce309a2fSJohn Baldwinotherwise it will return 0.
53ce309a2fSJohn BaldwinIf the
54ce309a2fSJohn Baldwin.Fn feature_present
55ce309a2fSJohn Baldwinfunction is not able to determine the presence of
56ce309a2fSJohn Baldwin.Fa feature
57ce309a2fSJohn Baldwindue to an internal error it will return 0.
58ce309a2fSJohn Baldwin.Sh RETURN VALUES
59ce309a2fSJohn BaldwinIf
60ce309a2fSJohn Baldwin.Fa feature
61ce309a2fSJohn Baldwinis present then 1 is returned;
62ce309a2fSJohn Baldwinotherwise 0 is returned.
63ce309a2fSJohn Baldwin.Sh SEE ALSO
64ce309a2fSJohn Baldwin.Xr sysconf 3 ,
65ce309a2fSJohn Baldwin.Xr sysctl 3
66ce309a2fSJohn Baldwin.Sh HISTORY
67ce309a2fSJohn BaldwinThe
68ce309a2fSJohn Baldwin.Fn feature_present
69ce309a2fSJohn Baldwinfunction first appeared in
70ce309a2fSJohn Baldwin.Fx 8.0 .
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