From owner-freebsd-hackers@FreeBSD.ORG  Tue Jul 29 22:14:32 2003
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Date: Wed, 30 Jul 2003 09:14:25 +0400 (MSD)
From: Dmitry Morozovsky <marck@rinet.ru>
To: Joshua Oreman <oremanj@www.get-linux.org>
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Subject: sparse files from shell [Re: file size different from ls to du]
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On Tue, 29 Jul 2003, Joshua Oreman wrote:

[snip]

JO> Usually programs will manage their own sparse files; it's something hard
JO> to do at the shell.

dd is your friend.

These commands make sparse file of some ks physical and 1g logical:

VNFILE=/tmp/sparsefile
VNSZ=$((1024*1024))
dd if=/dev/zero of=${VNFILE} bs=1k count=1 seek=$((${VNSZ} - 1))


Sincerely,
D.Marck                                     [DM5020, MCK-RIPE, DM3-RIPN]
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*** Dmitry Morozovsky --- D.Marck --- Wild Woozle --- marck@rinet.ru ***
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