Subject: Re: A random thought about partitioning
To: "Jones, Carrie" <>
From: Chris G. Demetriou <>
List: tech-userlevel
Date: 08/11/2000 11:19:06 ("Jones, Carrie") writes:
> I know that if you go through install programs (i.e. freebsd, open etc ad
> nauseum) that overlapping partitions are not allowed. Are there any
> situations where people need to have overlapping partitions?

need, perhaps not.  want, definitely.

The install programs don't allow overlap because, by and large, people
using the install programs don't need or want them.

Personally, I like to keep the same exact disklabel on all disks of
the same type that I own.  That's regardless of the actual use of the
data on the disk.  One whole disk, one split M ways, one split N
ways...  and then put the file systems and partitions down as needed.
(I'm keen on this because it means if something goes wrong with the
first few sectors of the disk, I never really have to guess what the
label on the disk was.)

i could have sworn that at some point there was a check to prevent
opens of overlapping block devices (at the same time), but I don't see
it there now.  It's not clear to me why you'd ever need to have
multiple overlapping block partitions open, unless you're trying to do
something Really Weird (like copying from one to another, where they
overlap, but you know you're safe due to the sequential nature of the
copy... but i still think that's iffy.  (raw/character-device
partitions are a different matter of course.)