From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <7359f049040927175156a92c6b@mail.gmail.com>
Date: Mon, 27 Sep 2004 17:51:54 -0700
From: Rob Pike <robpike@gmail.com>
To: Fans of the OS Plan 9 from Bell Labs <9fans@cse.psu.edu>
Subject: Re: [9fans] simple questions on bind semantics
In-Reply-To: <20040928004656.GA2117@submarine>
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Because bind and mount are implemented by a simple substitution.
When a walk hits a file that has been bound to, the fid is dropped
and then replaced by a clone of the fid of the result of the bind.
To have a fid, one needs a file, hence the fid must exist.

There's nothing stopping a service from creating bind destinations
on demand, and I think this has even been done in a special
device(memory is vague), but fundamentally, bind needs a file to
bind to.

-rob


On Mon, 27 Sep 2004 17:46:57 -0700, Roman Shaposhnick <rvs@sun.com> wrote:
> I have a deja vu feeling that this might have been asked here before.
> But since the mighty google disagrees here it goes: why does bind
> have a restriction that old has be existent ? Basically why can't
> I do:
> 
>    $ bind /some-file /new-name-for-some-file ?
> 
> where there's no /new-name-for-some-file before the call ?
> 
> Thanks,
> Roman.
>