Re: How Partition Numbers are Assigned in BOOT.INI

On Sun, 7 May 2006 16:40:41 -0700, "Timothy Daniels"

Part of the problem is that you don't understand how
a boot.ini file gets control. In the boot process, the MBR
(master boot record) of the HD that is at the head of the
BIOS's HD boot order gets control.

That MBR's executable code looks for the primary partition
that is marked "active" and passes control to it.

That's where the "system" phase ends and the "OS" begins.

The boot sector of that "active" partition looks for ntldr and
passes control to it. ntldr looks for boot.ini and if there are
more than 1 entry under the line "[operating systems]", it
displays the textual portion of boot.ini's entries as a menu
on the screen. Otherwise, ntldr just passes control to the
entry listed as "default".

True, where the boot sector is for the NT family. Other partition
boot record code may do other things, e.g. DOS or Win9x will look for
and pass control to IO.SYS instead, and other OSs do other things.

The other part of the problem (which you're aware of) is
how hiding a partition affects the meaning of "x" in the
"partition(x)" segment of each boot.ini entry. IOW, can
"partition(x)" refer to a partition that is hidden, or does
the numbering space close up to ignore the hidden
partition?

AFAIK, the Boot.ini syntax numbering counts which of the 4 possible
partition table entries it is, without any reference to what those
entries are - it's purely a matter of position.

AFAIK, hiding a partition doesn't change any order of entries; it
merely sets the partition type byte to something the OS doesn't
understand, and is expected to ignore.

An OS that "discovers" (and delves into) partitions that are not
marked as of that OS's type is a badly-behaved OS looking for trouble.



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