From owner-freebsd-current@FreeBSD.ORG  Thu Oct  9 08:29:24 2003
Return-Path: <owner-freebsd-current@FreeBSD.ORG>
Delivered-To: freebsd-current@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id A82D916A4B3
	for <freebsd-current@freebsd.org>;
	Thu,  9 Oct 2003 08:29:24 -0700 (PDT)
Received: from critter.freebsd.dk (critter.freebsd.dk [212.242.86.163])
	by mx1.FreeBSD.org (Postfix) with ESMTP id 8C5B743FEA
	for <freebsd-current@freebsd.org>;
	Thu,  9 Oct 2003 08:29:22 -0700 (PDT)
	(envelope-from phk@phk.freebsd.dk)
Received: from critter.freebsd.dk (localhost [127.0.0.1])
	by critter.freebsd.dk (8.12.9/8.12.9) with ESMTP id h99FSpnI000652;
	Thu, 9 Oct 2003 17:29:00 +0200 (CEST)
	(envelope-from phk@phk.freebsd.dk)
To: David Gilbert <dgilbert@dclg.ca>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Thu, 09 Oct 2003 10:02:34 EDT."
             <16261.27258.563735.274938@canoe.dclg.ca> 
Date: Thu, 09 Oct 2003 17:28:51 +0200
Message-ID: <651.1065713331@critter.freebsd.dk>
cc: freebsd-current@freebsd.org
cc: ecsd <ecsd@ecsd.com>
Subject: Re: cannot create partition entries for /dev/ad3 
X-BeenThere: freebsd-current@freebsd.org
X-Mailman-Version: 2.1.1
Precedence: list
List-Id: Discussions about the use of FreeBSD-current
	<freebsd-current.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-current>,
	<mailto:freebsd-current-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-current>
List-Post: <mailto:freebsd-current@freebsd.org>
List-Help: <mailto:freebsd-current-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-current>,
	<mailto:freebsd-current-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Thu, 09 Oct 2003 15:29:24 -0000

In message <16261.27258.563735.274938@canoe.dclg.ca>, David Gilbert writes:

>But filesystems also have persistence.  In the trivial case, the
>persistence of the object (say ... a disk) preserved the filesystems
>node.  But if I walk into /dev and change the permissions on a node,
>this persists only until the next reboot.

Rubbish!

When did you last see your changes to /proc survive a reboot ?

What you call a "filesystem" is really a name-resolution facility
which translates what you think of as a "filename" into a particular
kernel object.

That kernel object can be a file on a persistent media, a file on
a non-persistent media, a socket, a FIFO, a device, a process
and almost any oddball thing you can can come up with.

Persistence is a very optional property and it has nothing to do
with the object living in the filesystem naming space.


-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.