[rescue] Mac Hints needed

Joost van de Griek joost at jvdg.net
Tue Nov 4 11:03:52 CST 2003

On 2003-11-04 08:51, Geoffrey S. Mendelson wrote:

> James Birdsall wrote:
>> A genuine question: why did Apple go to so much trouble to make sure that
>> Macs can't boot anything but MacOS?
> They did not. For example, while they did have a proprietery boot
> system, they replaced it with a clone of Sun's "Open Boot" in the later
> G3's.

It's Open firmware, of which Sun's OpenBoot is another version/clone.

Open Firmware is an industry standard.

> The reason that the "alternative" operating systems, boot from MacOS and
> not native on the older Macs, was that once it was set up that way no
> one wanted to spend the time and effort to make a native bootloader.
> AFIK except for possibly a short time in the CHRP days, an APPLE
> computer came with MacOS. It wasn't an option, one could not be
> purchased without the other. I'm not even sure that you could buy a
> APPLE CHRP without MacOS.

As far as Apple are concerned, a Mac runs Mac OS, and nothing else.

> I know that the new Macs are CHRPS, or very close to them, but APPLE is
> not interested in promoting them as such, nor or the other players still
> offering COMMERCIAL CHRP operating systems, e.g. Sun and Microsoft.

Apple never made a CHRP machine, or at least never sold one. They very
likely had prototypes at one time, but while some DHCP features made it into
Macs, they never marketed a fully DHCP-compliant machine.

> I don't know about AIX, is it still available for APPLE computers? Will
> it run on a G5?

No. Apple only ever made two machines that ran AIX; the Apple Network Server
500 and the ANS 700. They are no longer supported by newer versions of AIX.

> MacOS 10.0, 10.1 and 10.2 woudl boot on a "old world" (not Open Boot)
> Mac, but do not require the ROM image at all. The BSD operating system
> does not use it at all, nor does the GUI.

Old World/New World and Open Firmware are two different things. Open
Firmware has been present in Macs since they switched from NuBus to PCI
architecture. New World Macs have no Mac OS-specific ROMs. They load the Mac
ROM contents from disk at boot time (if so required, i.e. When running the
classic Mac OS).

> The latest MacOS X (10.3) will not boot on a Mac without Open Boot, but
> there is a third party program that runs under MacOS 9 that will boot it.

No version of Mac OS X will run on a non Open Firmware Mac. Panther (10.3)
will not boot on Old World Macs.

If a mute swears, does his mother wash his hands with soap?
Joost van de Griek

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