From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <2ad1abed64a82f7e3056f7c64ab2c0c3@vitanuova.com>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] design clairvoyance & the 9 way
From: rog@vitanuova.com
In-Reply-To: <8354d64f77792b8840eeaf838a906783@plan9.bell-labs.com>
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Date: Thu,  8 May 2003 17:52:37 +0100
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> If I have the same file server mounted on my terminal
> and in my cpu session, then I'd like
>
> 	cp /mnt/term/usr/rsc/lib/profile /usr/rsc/lib/profile
>
> not to silently truncate my profile.

i don't believe that's possible to solve (without some special
mechanism for detecting identical files) unless you have globally
unique qids, which i think would go against the grain in plan 9.

the other problem you mentioned in a previous message: it would be
nice if a cpu server could know that all the copies of rc that it's
running are actually the same binary.  this is an easier problem:
Ropen could contain an optional SHA1 hash of the contents, venti
style; in this case you don't care if they're the same file, just that
the contents are identical.

at least variable length qids would get rid of those insidious
exportfs qid hacks and enable encapsulation without worries.