From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <23ca7e8f532ce9bce873c8591ebaed9a@vitanuova.com>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] sanity check
Date: Mon, 26 Sep 2005 18:16:32 +0100
From: rog@vitanuova.com
In-Reply-To: <97cf5bb32e4e73066bfbf1be4bcb8a49@quintile.net>
MIME-Version: 1.0
Content-Type: text/plain; charset="US-ASCII"
Content-Transfer-Encoding: 7bit
Topicbox-Message-UUID: 9142aec2-ead0-11e9-9d60-3106f5b1d025

> What I have done is to modify 9fs such that if you do
> 9fs xxx and /srv/xxx exists then 9fs just mounts xxx.

this is the default for 9fs entries that are not explicitly
dealt with (as implemented by srv(4)).

> Thus if cifs is not running I can type 9fs dfs to connect to
> dfs in "this" window, and plumb 'Local 9fs dfs' to export it to
> all new windows. I usually close any idle windows and if there
> is one or two I want to keep I just do 9fs dfs again in those
> (and !9fs dfs in my sam window) to attach them.
> 
> I just live with this behavior it just seems reasonable to me -
> but perhaps I am just used to it.

i use exportfs to provide an extra level of indirection
which gets around this awkwardness, providing a globally shared,
mutable namespace in /n.

i can plumb "Local 9fs dfs" and /n/dfs in all processes will contain
the newly acquired namespace. (actually i have a shell script,
named "local" which is this:

	#!/bin/rc
	plumb 'Local ' ^ $"*

[it's kind of ironic that it's named "local" when actually the desired
effect is a global one...]

thus in any window, i can do

	local 9fs sources

and plumb files /n/sources to any other preexisting
window (for example page). i find this extremely convenient.

unlike nemo's volfs (which i haven't actually looked at, i'm afraid),
this doesn't do automatic fid rewrites when the underlying space is
changed, but it is implemented from existing parts in only 4 lines of shell script,
and imposes negligible overhead.

the DFS scheme suggested earlier could be easily implemented by using
a variation on this scheme.