Re: Boot.ini question

En news:43e8ee3e$0$30450$5a62ac22@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx,
Rod Speed va escriure:
Antoine Leca <root@xxxxxxxxxxxxxxxxx> wrote
Rod Speed wrote
Antoine Leca <root@xxxxxxxxxxxxxxxxx> wrote
What you seem to miss is that Tim's BIOS does not have such a
concept.
Irrelevant to the whole point of the rdisk() parameter.
Problably yes. Like the most part of this thread...
Nope,

You are saying the same as I said: most of this thread (not just the post
quoted above) is irrelevant to the...
the whole point of this thread is what the rdisk() param means,


Sure, one of my BIOS, and an awful large number of other BIOSes
out there as well, do have such drives; yet, there are other BIOSes
which allow to boot easily from any drive recognized by the BIOS
(BAID),

Not when its a logical drive in an extended dos partition.

Now *I* ask what is the relevance of this remark
with the whole point of the rdisk() parameter.

The whole point of the boot.ini was to allow booting of what the bios
could not boot.

Admitting.

That is STILL true of a logical drive in an extended dos partition,

What is true?
A boot loader allows to sever the link between the booting (active)
partition and the kernel location. Great.

almost no current bios allows those to be booted by the bios.

Because that is not BIOS' job, rather the one for the code inside the boot
records (MBR and the one for the active partition); if there is code at the
beginning of the extended partition(s) to load the logical one, and if there
is the correct code in the boot record of your logical drive, you'll
succeed.

I perfectly know IBM/Microsoft's Fdisk does not store such code.

I'm not aware of any that allows that.

Almost any BIOS is able to do it.


For what it is worth, I think it is possible to succesfully
boot Ntldr in a logical partition, using bootstrap code
in EPBR and changing the HiddenSectors parameters.

I wasnt talking about that, I was talking
about where the OS comes from, not ntldr.

Then please reformulate, I did not catch your point at all.


The very purpose of Ntldr+Boot.ini, like any
boot loader, is to enhance flexibility, yes.

And to allow booting that the bios cannot do, like
booting an install of the NT/2K/XP family from a
logical drive within an extended dos partition.

And booting several OS installed in the same partition, perhaps of different
vintage (something that was really horrible back in OS/2 time).


as I am saying since the first post after Tim's...

As I also said a number of times in this thread.

Yes :-). This thread is full of repetitions and not very useful comments. I
do not believe you and I are likely to learn anything. I wonder if anyone is
going to learn anything at this point, in fact.


If there
aint even a hard drive boot order list, the rdisk() param
cant possibly be the ordinal in the hard drive boot order
list because there isnt one in some bios.

Was my point in the first place :-).


One is that the ARC path rdisk(N) mechanism was designed around
1990 to make a gateway between the RISC world (where NT originally
was born) and the Intel/IBM/Compaq "i386" architecture; that's long
before BBS. I very much doubt if MS had the choice, they will still
use it in 2006 (NT on MIPS anyone?) As such, it is much of a
legacy of the history, like for example the Int13 interface itself.

Thats just plain wrong with the most basic functionality of boot.ini,

???
Read http://support.microsoft.com/kb/102873 (knowing that NT was born on
MIPS) and you'll see that Boot.ini is a "solution" to supplement the lack of
a firmware way to record strings in a PC.


to provide a way to specify where the various OSs etc are on the
hard drives. That has to do be done somehow with any boot manager.

It could have been done using the disk(N) parameter instead, like with SCSI,
and it would have worked equally well. The fact there are two indices is a
given input, not a decision of the team. Using ARC paths including for i386
also was.

N could also have been defined clearly as the BIOS drive number, also
(signature() translates to scsi(128), for instance, although it came later).


It surely is convenient to be able to boot from another disk, but the main
beef for the ARC path and boot.ini is really with partition(N) and \WINNT,
not rdisk(N).



<snip>
Nothing grey about the MS statement that the rdisk()
param is the ordinal of the drive on the controller.

I did not find a clear statement from them that the rdisk() parameter is the
BIOS drive number - 80h.



Antoine

.

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