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Cc: freebsd-arch@freebsd.org
Subject: Re: kernel features MIB
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On Fri, 28 Dec 2007, John Baldwin wrote:

> On Thursday 27 December 2007 05:04:44 pm John Baldwin wrote:
>
>> At work we don't have a pretty API for this at all, but I'm thinking for 
>> FreeBSD we can do this:
>>
>> FEATURE(foo, "description of foo")
>>
>> which is a macro to create the 'kern.features.foo' node and set it to 1. 
>> Then we could have a routine in libc:
>>
>> int feature_present(const char *name);
>>
>> That returns a boolean to indicate if a given feature is present or not by 
>> invoking sysctlbyname(3), etc.
>>
>> Any objections to the idea?
>
> So here's a bikeshed question I have no idea for.  Which header should 
> feature_present()'s prototype go in?  I anticipate this routine being used 
> in libc itself, so I don't think it can go into libutil.

#include <sys/feature.h>

feature_check(2)?

Does POSIX talk about the namespace for non-portable names being passed to 
sysconf(3)?

Robert N M Watson
Computer Laboratory
University of Cambridge