Timothy Daniels wrote
Rod Speed wrote
Timothy Daniels wrote
Antoine Leca wrote

rdisk(N) is the "real" disk number (as assigned by
the BIOS - 0x80; and up to 3 according to MS doc).

You can also think of "rdisk()" as meaning the
"relative disk position", that is, relative to the head of the BIOS's
hard drive boot order.

No you cant.

Since the boot order can be adjusted manually by the
user via keyboard input to the BIOS, the hard drive
referred to by "rdisk(0)" can be changed at will.

No it cant. The boot order setting doesnt
change the N in the rdisk entry.

Thus, "rdisk(0)" will refer to the top of the boot
order list, "rdisk(1)" will refer to the next in the list,
"rdisk(2)" will refer to the next after that, etc.,

No it doesnt. It has nothing to do with the boot order
list at all.

It JUST refers to the physical order.

but which hard drive those arguments refer to only
depends on cabling and I/O channel in the default case.

In all cases, actually. The boot order in the bios is
irrelevant to that.

I stand by my claim, Rod.

You can stand anywhere you like,
it changes absolutely nothing at all.

You can check if you want, and you can make all the denials you want, but
it is true, and anyone can check that out - the "rdisk()" parameter is
relative to the top of the hard drive boot order, and it only relates to
physical position, i.e. cable position or IDE channel number, in the
default case. In the DEFAULT case, the hard drive boot order is:

Thats just repeating your earlier assertion.

You can keep repeating that till you go blue
in the face if you like, changes nothing.

The obvious problem with your claim is trivial to prove.
Setup a test config where the boot.ini comes off the
first drive in the boot list in the bios, with an entry to
boot off a different physical drive. When you move
that later physical drive in the boot order in the bios,
that doesnt make any difference to which drive gets
booted when you select that entry in the boot.ini at
boot time. The N value changes according to you
because you have moved it in the bios boot sequence
list. XP still boots the same physical drive regardless.

Master, IDE channel 0,
Slave, IDE channel 0,
Master, IDE channel 1,
Slave, IDE channel 1.

But when this order is changed in the BIOS, the
meaning of "rdisk()" changes physically, but it retains
its logical meaning as a reference to the boot order.
That means that "rdisk(0)" will ALWAYS refer to the
head of the boot order, regardless of which physical
hard drive is put at the head of the boot order, and
"rdisk(1)" will ALWAYS refer to the next one in the list.

Again, that is just repeating original assertion and its
completely trivial to prove that its just plain wrong.

Accordingly, I code boot.ini files to implement
switching between up to 7 or 8 clone OSes which are
resident simultaneously on 3 hard drives in my computer,
and the "rdisk()" parameter has always meant what I've
described above. I base this on the behavior of my
Dell Dimension XPS system which is about as common
as a PC can get.

Doesnt explain the test I listed that proves you are just plain wrong.