From owner-freebsd-hackers  Tue Dec  4 15:39: 5 2001
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Date: Tue, 04 Dec 2001 15:38:57 -0800
From: Terry Lambert <tlambert2@mindspring.com>
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To: David Malone <dwmalone@maths.tcd.ie>
Cc: Dragon Fire <dragonfire820@mediaone.net>,
	freebsd-hackers@FreeBSD.ORG
Subject: Re: block devices
References: <005501c17cc4$c770d7a0$037d6041@gandalf> <20011204140738.A30798@walton.maths.tcd.ie>
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David Malone wrote:
> On Tue, Dec 04, 2001 at 08:08:34AM -0500, Dragon Fire wrote:
> > I was trolling around the FreeBSD kernel source and the dev directory and
> > noticed there is no bdevsw structure and no block driver files. Is
> > everything implemented in terms of character devices now? Looks like all the
> > support for block devices is contained in the cdevsw struct.
> 
> Since no userland programs ever really had a good excuse for
> accessing block devices they have been retired from /dev. Block
> devices still exist, but are only accessable within the kernel.

Actually, I found a third reason for block devices (apart from the
Apple UDF FS and disk initialization) the other day: to permit reading
of QIC-11 and QIC-24 tapes produeces on NCR Tower-XP, NCR Tower-32,
and Sun-3 equipment.

-- Terry

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