From mboxrd@z Thu Jan  1 00:00:00 1970
To: 9fans@cse.psu.edu
Subject: Re: [9fans] union directories
From: rog@vitanuova.com
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Date: Fri, 23 Mar 2001 13:08:24 +0000
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> > This is all a legacy of Unix's model that create means two different
> > things in the two situations.
>
> Well, there you go -- an attempt to create an existing file should
> fail.  That is a simpler and more useful property.

it's not just a problem with the semantics of the create() system call,
but with the shell too.

if i type:

	echo hello > /usr/rog/file

i expect /usr/rog/file to be created if it isn't already there, but
overwritten if it is.

if create didn't overwrite an existing file, the shell would have to do
exactly as the kernel does currently, and for most intents and purposes
you'd still get the same "dual meaning".

i think under 9p2000 it's possible to call create() with an OEXCL
option and get the semantics you suggest.

  cheers,
    rog.