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Date: Wed, 11 Jul 2007 10:53:25 -0700
From: Alfred Perlstein <alfred@freebsd.org>
To: Alexander Leidinger <Alexander@Leidinger.net>
Message-ID: <20070711175325.GQ45894@elvis.mu.org>
References: <20070711190546.4b202080@deskjail>
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Cc: Rui Paulo <rpaulo@fnop.net>, Shteryana Shopova <syrinx@FreeBSD.org>,
	"Constantine A. Murenin" <cnst@FreeBSD.org>,
	Poul-Henning Kamp <phk@phk.freebsd.dk>,
	Robert Watson <rwatson@FreeBSD.org>, freebsd-arch@FreeBSD.org
Subject: Re: Porting OpenBSD's sysctl hw.sensors framework to FreeBSD
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* Alexander Leidinger <Alexander@Leidinger.net> [070711 10:49] wrote:
> Quoting "Poul-Henning Kamp" <phk@phk.freebsd.dk> (Wed, 11 Jul 2007 17:33:51 +0000):
> 
> > In message <20070711190546.4b202080@deskjail>, Alexander Leidinger writes:
> > >Quoting "Poul-Henning Kamp" <phk@phk.freebsd.dk> (Wed, 11 Jul 2007 13:54:40 +0000):
> > 
> > >You are focusing on physical devices which are specially build as a
> > >sensor for some specific stuff. I put my focus on the kernel framework
> > >which allows to unify the handling of sensoric data from kernel
> > >devices.
> > 
> > I'm trying to point out that your kernel framework belongs in userland.
> 
> It's not my framework.
> 
> > There is no benefit from having it in the kernel.
> 
> You need to get some information out of the kernel somehow (you cut
> this part of my mail). And as far as I understand the high level
> description (presentation in the net) of this framework, this does this
> in an unified way. Do you propose to get the information out of the
> kernel in a non-uniform way?

Possibly, one way to do that is to provide a well thought out
userland library that can make for a nice interface.  If by
doing it userland the kernel implementation can be kept smaller
and more simple it might be a win.

That said, it may be a loss if you wind up having to duplicate
work over and over for different devices it may be a loss.

Remember, once the kernel interface is exposed it has to be there
almost forever, while a userland interface and much more easily
be adapted.

-- 
- Alfred Perlstein