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Date: Wed, 28 Dec 2011 13:56:31 +0100
From: Wojciech Zygmunt Porczyk <wojciech@porczyk.eu>
To: Gaurav Saxena <grvsaxena419@gmail.com>
Cc: John Stoffel <john@stoffel.org>,
        richard -rw- weinberger <richard.weinberger@gmail.com>,
        linux-kernel@vger.kernel.org
Subject: Re: Intercepting system calls
Message-ID: <20111228125631.GB9894@nb24cis>
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On Fri, Dec 23, 2011 at 10:33:45PM +0530, Gaurav Saxena wrote:
> I am trying to write an application which would create a backup for
> the system so that it could be restored as it is. For example I create
> a backup using my application. I just do nothing at time of backup so
> it would be fast. Now whenever I see any deletion I would save that
> file so that I could restore it.

You almost certainly wan't to research LVM(-like) snapshots. They are
operating in block layer, so you can restore fs "as it was", with COW
feature they do "nothing" at creation and just save overwritten data
somewhere else.

See: lvcreate(8), xfs_freeze(8). Maybe btrfs(8) ("btrfs subvolume
snapshot") but btrfs is not really production-ready, so get lvm2+xfs.

- -- 
regards
WZJP
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