[hfs-user] Embedded volume..

Entwicklung entwicklung@whengenibk.de
Fri, 22 Feb 2002 18:29:26 +0100


I noticed that the technical notes also mentioned -
'An HFS Plus volume is not required to have an HFS wrapper. In that case,
the volume will start at the first sector of the disk, and the volume header
will be at sector 2. However, Apple software currently initializes all HFS
Plus volumes with an HFS wrapper.'

Mark Day wrote :
'Since the Mac OS ROM only knows how to boot from HFS volumes, having an
embedded HFS Plus volume means I can boot from it directly, rather than
having to partition my disk with an HFS boot volume and an HFS Plus
volume for all my data.'

Simon Bazley wrote:
'You can create a HFS+ volume without the HFSWrapper if you
like, but old macs will just erase the disk for you if they encounter it.
Hence
all new Macs use HFS Wrappers.'


Going by the above  statements could I conclude that if I want to create a
non-bootable volume (a HFS/HFS+ CD-ROM to be specific) I don't need to
consider using an embedded volume at all?

I have a couple of questions to what Simon wrote - If my external HFS+
volume happens to be on a CD-ROM which is in any case a one-time writable
medium, how could older macs 'erase' the disk? I guess that probably happens
to CD-RW's which can be formatted or erased..... or did you mean something
else ?

And if I do have a wrapper on a HFS+ volume and insert it into an older Mac,
it would anyway not be readable though it doesn't get erased, right ?

Regards,
Nandini Hengen