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From: David Woodhouse <dwmw2@infradead.org>
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To: Padraig Brady <Padraig@AnteFacto.com>
Cc: William Stearns <wstearns@pobox.com>,
        ML-linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: [OFFTOPIC] Hardlink utility - reclaim drive space 
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Date: Wed, 07 Mar 2001 14:52:19 +0000
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Padraig@AnteFacto.com said:
> Wouldn't it be cool to have an extended attribute for files called
> "Copy on Write", so then you could hardlink all duplicate files
> together, but when a file is modified a copy is transparently created.

> The only problem I see with this is that you wouldn't have enough
> space to store a copy of a file, what would you do in this case, just
> return an error on write? 

Yep. write(2) is allowed to return -ENOSPC, even when you're not extending
the file you're writing to. Think about holes and log-structured
filesystems.

--
dwmw2


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