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To: Stefan =?iso-8859-1?q?E=DFer?= <se@FreeBSD.org>
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From: des@des.no (Dag-Erling =?iso-8859-1?q?Sm=F8rgrav?=)
Date: Sun, 23 Nov 2003 17:31:35 +0100
In-Reply-To: <20031123121501.GA1133@StefanEsser.FreeBSD.org> (Stefan
 =?iso-8859-1?q?E=DFer's?= message of "Sun, 23 Nov 2003 13:15:01 +0100")
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cc: Rayson Ho <raysonlogin@yahoo.com>
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cc: freebsd-hackers@freebsd.org
Subject: Re: "secure" file flag?
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Stefan E=DFer <se@FreeBSD.org> writes:
> What I'm suggesting is to have the obliteration implemented as an
> add on to the dirty buffer flush, with the difference that the=20
> buffer contents is prepared for the next step of the erasure process,
> written out, and then not declared free but again prepared for the
> next overwrite pass.

This next pass won't be until thirty seconds later, so it'll take
about half an hour to completely obliterate a file.  Furthermore,
unmounting a file system less than half an hour after a file is
deleted or truncated will fail, and shutting down will most likely
leave the file system unclean due to repeated failures to flush the
dirty buffer list.

DES
--=20
Dag-Erling Sm=F8rgrav - des@des.no