feature_present.3 revision 222286
Copyright (c) 2008 Yahoo!, Inc.
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Written by: John Baldwin <jhb@FreeBSD.org>

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$FreeBSD: head/lib/libc/gen/feature_present.3 222286 2011-05-25 14:13:53Z ru $

.Dd January 8, 2008 .Dt FEATURE_PRESENT 3 .Os .Sh NAME .Nm feature_present .Nd query presence of a kernel feature .Sh LIBRARY .Lb libc .Sh SYNOPSIS n unistd.h .Ft int .Fn feature_present "const char *feature" .Sh DESCRIPTION The .Fn feature_present function provides a method for an application to determine if a specific kernel feature is present in the currently running kernel. The .Fa feature argument specifies the name of the feature to check. The .Fn feature_present function will return 1 if the specified feature is present, otherwise it will return 0. If the .Fn feature_present function is not able to determine the presence of .Fa feature due to an internal error it will return 0. .Sh RETURN VALUES If .Fa feature is present then 1 is returned; otherwise 0 is returned. .Sh SEE ALSO .Xr sysconf 3 , .Xr sysctl 3 .Sh HISTORY The .Fn feature_present function first appeared in .Fx 8.0 .