JP>> I, in my turn, (perhaps because I have never used one) don't remember
 >> offhand when the PS/2 came along, but I do happen to know that the
 >> whole idea of an "extended partition" was new to MS-DOS version 3.3. 
 >> MS-DOS 3.2 and earlier didn't know about "primary" partitions.  It
 >> just had "partitions", and there could be a maximum of four of them. 
 >> If they were formatted as FAT, they could be a maximum of 32MeB in
 >> size, meaning that the largest possible "all FAT" hard disc size was
 >> approximately 128MeB .

 ML>     "Possible" from an addressing standpoint doesn't necessarily mean
 ML> "exists."  According to Deitel and Kogan (The Design of OS/2), DOS
 ML> 3.3 was introduced in 1987 to support the PS/2 80386/80387 real mode
 ML> and the 3.5" 1.44 MB diskette.  I bought my PS/2 model 80 (the only
 ML> model in the original PS/2 release with an 80386) in early 1988 (the
 ML> machine died in late 1999).  IIRC, the maximum available hard-drive
 ML> capacity at the time of that first release was two 70 MB ESDI drives.

Which of course still proves my original point.  One could not have made use
of a single 70MeB hard disc drive *without* having multiple visible primary
partitions, given that each individual partition couldn't have been larger
than 32MeB.  Indeed, one would have used three out of a maximum of four.

So, as I said before, it isn't the case that Microsoft has introduced
something *new* here to shift the goalposts and to confound other operating
systems, which is what you implied before and what you obliquely implied again 
at the end of the message that I'm replying to here where you talked about
monopolies ignoring their legacy customers.  The concept of multiple visible
primary partitions has a long pedigree going back to the earliest versions of
MS-DOS/PC-DOS, and the fact that OS2DASD.DMD doesn't support such an
arrangement must be viewed as OS/2 being incompatible with long-standing
existing practice.  And, ironically, it is *Microsoft* that is better
supporting legacy customers (who want to have multiple visible primary
partitions, just like they use to have) here.

One can of course argue, as several here have done, that having multiple
visible primary partitions is a concept that is no longer necessary given the
existence of extended partitions, and that OS/2 is therefore justified in not
supporting such a legacy arrangement.  I don't happen to agree with that
myself.  But one cannot argue, even by implication, that it is Microsoft that
changed the goalposts here.  It is OS/2 that has diverged from common practice 
in PC operating systems, not the other way around.

I suspect that this divergence was unintentional.  But intentional or not, it
is still a bug in OS2DASD.DMD that needs fixing.

 ¯ JdeBP ®

--- FleetStreet 1.22 NR
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