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From: Ruediger Meier <sweet_f_a@gmx.de>
To: util-linux@vger.kernel.org
Subject: BUG: wipefs dry run
Date: Wed, 10 May 2017 11:54:50 +0200
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Hi,

I wonder why wipefs does not show all MBR and GPT signatures which would
be deleted by using "-fa".

$ truncate -s 100M /tmp/CCC
$ ./sfdisk /tmp/CCC <<EOF
> label: gpt
> label-id: 384A8F14-17FF-4782-A190-A5B858E3FCF0
> device: /tmp/CCC
> unit: sectors
> first-lba: 34
> last-lba: 204766
> EOF

$ ./wipefs  -fa --no-act   /tmp/CCC
/tmp/CCC: 8 bytes were erased at offset 0x00000200 (gpt): 45 46 49 20 50 
41 52 54

$ ./wipefs  -fa    /tmp/CCC
/tmp/CCC: 8 bytes were erased at offset 0x00000200 (gpt): 45 46 49 20 50 
41 52 54
/tmp/CCC: 8 bytes were erased at offset 0x063ffe00 (gpt): 45 46 49 20 50 
41 52 54
/tmp/CCC: 2 bytes were erased at offset 0x000001fe (PMBR): 55 aa


cu,
Rudi