From owner-freebsd-hackers@FreeBSD.ORG  Tue Aug  1 13:36:53 2006
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Date: Tue, 1 Aug 2006 14:36:38 +0100
From: David Taylor <davidt@yadt.co.uk>
To: freebsd-hackers@freebsd.org
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Subject: Re: [PATCH] adding two new options to 'cp'
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On Tue, 01 Aug 2006, Ivan Voras wrote:

> Peter Jeremy wrote:
>=20
> >Note that it isn's possible to accurately distinguish between a block
> >of NULs and a hole in the file through the filesystem.  The only way
> >to accurately copy a sparse file is with dump/restore.
>=20
> Hence the need for an explicit switch.

A switch doesn't help.  A sparse file can contain both holes and blocks
of NULs.  You could, I suppose, do something like -s 100, which would
seek past any block of >100 NULs.

--=20
David Taylor