Hard disk Partitions

[Timothy A. Seufert]

At 3:22 PM -0700 8/26/02, Bill Mueller wrote:
>Thanks Timothy for the info,
>
>I tried your suggestions, and a combination there in, and I still can't get
>both types of partitions onto the same disk.  The HFS system seems to need 4
>extra partitions starting from the beginning of the disk to be reconized as
>an HFS volume.

Sorry, I should have mentioned that if you plan on using the disk in 
MacOS 9, you need to let the MacOS formatter do its thing and create 
those partitions.  They are disk driver partitions for "classic" 
MacOS, which cannot mount or boot a disk without drivers.

As it sounds like you've already discovered, you don't need the 
driver partitions if MacOS is running under MOL.  It provides its own 
MacOS disk drivers in order to avoid emulating IDE or SCSI hardware.

>I can make an HFS partition on a DOS partitioned drive with the hformat, but
>can't get it to boot MAC OS because it doesn't reconize the volume.  pdisk
>is only reconizing/creating Apple file systems, just as fdisk only does dos.
>
>The end result of this whole escapade is to be able to boot linux or dos.
>If boot into linux, to boot into MAC OS using Mac on Linux.  All on the same
>disc.

As you've discovered, the only way to do this is to have DOS 
partition tables and give up the ability to boot MacOS natively -- 
which I'm guessing is probably no loss to you.  Also, it may not work 
on all Macs; I believe that the ability for Open Firmware to parse 
DOS partition tables was not introduced until the New World Macs.

You've made me quite curious; what is the reason for doing this?  Do 
you take this disk and move it between an Intel machine and a Mac?

>Is there any type of setup where a link or pointer can be used to simulate
>the HFS volume/dos volume residing at the beginning of the disk?

I know of no way to mix both partition table types on one disk and 
retain full functionality.  The hack mentioned by 
hanai@koto.kpu-m.ac.jp cannot boot an Intel machine, probably because 
Apple partition tables use block 0 of the disk and I think that's the 
same place the boot block is supposed to go for bootable disks on 
Intel machines.
-- 
Tim Seufert