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From: Luigi Rizzo <luigi@labinfo.iet.unipi.it>
Message-Id: <199704131233.OAA23332@labinfo.iet.unipi.it>
Subject: Re: on the subject of changes to -RELEASEs...
To: jkh@time.cdrom.com (Jordan K. Hubbard)
Date: Sun, 13 Apr 1997 14:33:46 +0200 (MET DST)
Cc: hackers@freebsd.org
In-Reply-To: <16068.860935013@time.cdrom.com> from "Jordan K. Hubbard" at Apr 13, 97 05:36:34 am
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> Maybe it's time for a proof-of-concept implementation, so we can
> stop arguing about intangibles (which are always the easiest things
> to argue about :-).

the simplest way to implement the /etc -> /var/etc idea would be
to have the kernel load say /etc_rc instead of /etc/rc (one byte
change in the kernel!), which would contain the following:

    /etc_rc:
    
    #!/bin/sh
    stty status '^T'
    trap : 2 
    trap : 3
    HOME=/; export HOME
    PATH=/sbin:/bin:/usr/sbin:/usr/bin:/usr/local/sbin
    export PATH
    swapon -a
    VARFS=/dev/wd0e	# or whatever, e.g. /dev/vn0...
    ### using VARFS you don't need /etc/fstab here...
    ### do whatever is needed to mount /var
    ### truly diskless system might need to mount /usr and/or /home
    ### in order to do
    ###		vnconfig /dev/vn0 /home/my.var.image
    mount $VARFS /var
    exec /etc/rc
    
Existing /etc/rc can be pretty much unchanged (perhaps with the
only exception of the line specifying "umount -a ..." I am uncertain
if both / and /var are locked at that point and will not be unmounted.

Now, do you like it this way ?

	Cheers
	Luigi
-----------------------------+--------------------------------------
Luigi Rizzo                  |  Dip. di Ingegneria dell'Informazione
email: luigi@iet.unipi.it    |  Universita' di Pisa
tel: +39-50-568533           |  via Diotisalvi 2, 56126 PISA (Italy)
fax: +39-50-568522           |  http://www.iet.unipi.it/~luigi/
_____________________________|______________________________________