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Subject: Re: silent semantic changes with reiser4
From: Shaya Potter <spotter@cs.columbia.edu>
To: Alex Zarochentsev <zam@namesys.com>
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Date: Sun, 29 Aug 2004 08:52:46 -0700
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On Sun, 2004-08-29 at 16:34 +0400, Alex Zarochentsev wrote:

> Do you mean COW files or some another thing?  For COW files, the reiser4
> support is not enough, we need to teach cp(1) or another utility to inform the
> fs layer that copying can be done by creation of COW files.

it's easy enough to add that via an fs ioctl(), I did the equivalent
last semester for some research I'm doing while using ext3cow (which
unfortunately was put on hold for the summer), it's just a take off of
sys_link(), a sys_cowpy() of sorts.