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Date:      Thu, 9 Oct 2003 10:02:34 -0400
From:      David Gilbert <dgilbert@dclg.ca>
To:        "Daniel O'Connor" <doconnor@gsoft.com.au>
Cc:        ecsd <ecsd@ecsd.com>
Subject:   Re: cannot create partition entries for /dev/ad3
Message-ID:  <16261.27258.563735.274938@canoe.dclg.ca>
In-Reply-To: <200310071929.30826.doconnor@gsoft.com.au>
References:  <3F8279C5.9070300@ecsd.com> <200310071929.30826.doconnor@gsoft.com.au>

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>>>>> "Daniel" == Daniel O'Connor <doconnor@gsoft.com.au> writes:

Daniel> The only reason most people will ever touch /dev is to either
Daniel> make devices (hence no longer necessary with devfs), or change
Daniel> permissions. The later is more difficult with devfs, but IMHO
Daniel> the tradeoff is worthwhile.

This brings me to my (small) beef with devfs.  When you invoke an
abstraction, a metric of the usefulness of that abstraction is how
well the abstractions metaphors map onto the target system's
metaphors.

So as a filesystem, devfs does will by replicating the average
person's view of should be in /dev ... subject to what devices are
actually found... 

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.

Now... part of the problem here is that there is no simple interface
for the kernel to access (and update) a file ... which might be an
easy way to store persistence... but that's all a larger design
problem.

Now we do have the /etc/devfs.conf ... but this doesn't (yet) approach
the topic of devices added and removed from the system.  Maybe this is
a natural extension for devd.

Dave.

Dave.

-- 
============================================================================
|David Gilbert, Independent Contractor.       | Two things can only be     |
|Mail:       dave@daveg.ca                    |  equal if and only if they |
|http://daveg.ca                              |   are precisely opposite.  |
=========================================================GLO================

-- 
============================================================================
|David Gilbert, Independent Contractor.       | Two things can only be     |
|Mail:       dave@daveg.ca                    |  equal if and only if they |
|http://daveg.ca                              |   are precisely opposite.  |
=========================================================GLO================



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