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To: "Andrey V. Elsukov" <ae@FreeBSD.org>
From: Raoul MEGELAS <rmgls@free.fr>
Date: Sun, 30 Sep 2012 21:06:57 +0200
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Cc: freebsd-current@freebsd.org
Subject: Re: gpart on macbook air
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On Sun, 30 Sep 2012 21:43:50 +0400
"Andrey V. Elsukov" <ae@FreeBSD.org> wrote:

> On 30.09.2012 20:37, Raoul MEGELAS wrote:
> > i installed CURRENT on a macbook air
> > (internal ssd as you know):
> > i noticed the following:
> > 
> > 1. on freebsd, deleting a partition with gpart: say
> > gpart delete -i 4 ada0
> > dammage the osx boot.
> > of cours, booting with a backup disk and repairing the disk
> > make it functional again.
> > any light woukd be appreciated on this topic.
> 
> Hi,
> 
> When you are deleting a partition, the kernel completely overwrites  the
> partition table and PMBR area. You can compare first 34 blocks before
> deletion and after to see what is going on.
> 
> -- 
> WBR, Andrey V. Elsukov

Hi Andrey,

I can understand that, but i would have thought
that the deletion of the concerned partition was written preserving others???

something like:

- read the gpt table
- find the offset
- zeroes the partition entry
- rewrites the table?

is not that logic?

if it is not so, i does not understand this behaviour.

Thanks.

raoul
rmgls@free.fr