From mboxrd@z Thu Jan  1 00:00:00 1970
From: Shaya Potter <spotter@cs.columbia.edu>
Subject: Re: [PATCH 01/24] Unionfs: Documentation
Date: Mon, 8 Jan 2007 14:43:39 -0500 (EST)
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Cc: "Josef 'Jeff' Sipek" <jsipek@cs.sunysb.edu>,
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On Mon, 8 Jan 2007, Andrew Morton wrote:

> On Sun,  7 Jan 2007 23:12:53 -0500
> "Josef 'Jeff' Sipek" <jsipek@cs.sunysb.edu> wrote:
>
>> +Modifying a Unionfs branch directly, while the union is mounted, is
>> +currently unsupported.
>
> Does this mean that if I have /a/b/ and /c/d/ unionised under /mnt/union, I
> am not allowed to alter anything under /a/b/ and /c/d/?  That I may only
> alter stuff under /mnt/union?
>
> If so, that sounds like a significant limitation.

haven't we been through this?  It's the same thing as modifying a block 
device while a file system is using it.  Now, when unionfs gets confused, 
it shouldn't oops, but would one expect ext3 to allow one to modify its 
backing store while its using it?