(Excerpts from a message dated 11-12-99, Eddy Thilleman to Murray
Lesser)

Hi Eddy--

ET>Drive letters are assigned at boot time by the booting operating
  >system. The first primary partition will gets drive letter C: 
  >(regardless of which partition is booted) and all other primary
  >partitions on the same disk with the recognized true partition type
  >will get subsequent drive letters (in the order they are laid out on
  >the harddisk).

    Almost every other OS/2 user agrees that your above assertion is not
true under boot manager (all the bootable primary partitions on the
first hard drive that boot manager knows about, except the one it is in,
will have the drive letter C:.  Also, if you have one primary partition
on the first hard drive, with or without boot manager installed, and a
primary partition on the second hard drive, the primary partition on the
second hard drive will be assigned the drive letter D: by any operating
system that I have used.  That is why I have only one primary portion on
my wife's OS/2 system, which has two hard drives installed.

ML> As a consequence, none of the booted systems can see any other
ML> bootable partition because you can have only one active C: drive on a
ML> system at a time.

ET>This is not true. I know DOS can see them all because I've seen that
  >on someone else' system with this setup.

    See a recent post from JdeBP to me for an explanation of how this
may be done.  I assume that he agrees with me that it is very poor
practice to play this game.  In any case, "someone else" was not running
OS/2 Boot Manager :-).  According to a post to Linda from John Thompson,
recent versions of Windows can also see all primary partitions.  (He
doesn't know whether this is "a good thing," either.)  But there goes
Microsoft again, making up its own rules as it goes along :-).

ML> With this exception, in general, OS/2 can see all primary partitions
ML> and extended partitions, but may not be able to read them.

    On more mature thought, I believe that the above statement is
incorrect.  As noted in other posts (not from me), there are several
other exceptions to the "see all primary partitions" assertion.

ML> OTOH, neither DOS nor Win95 can see partitions formatted HPFS, whether
ML> primary or extended.  This is not a valid reason not to use HPFS for
ML> big partitions; perhaps it is a valid reason not to boot DOS nor Win95
ML> :-).

ET>DOS and any winxx version don't recognize and so can't use HPFS
  >partitions, but not because they can't see them. :)

    They don't assign drive letters to them, either!  Can you tell me
the practical difference between "don't recognize" and "can't see?"

ML> that one never use FAT partitions (of any size) containing more than
ML> 500 files.

ET>On a FAT partition: if there are more than 500 files in the same
  >directory and only when that directory is accessed.

    According to the IBM white paper I mentioned in the message to Linda
that you replied to, it was 500 files in a FAT _partition_, and 5000
files in an HPFS _directory_.  If you are interested in reading the
paper for yourself, the file is WARPPERF.ASC and is available to guests
for download from the DevCon Web site, as well as being on all recent
DevCon CD-ROMs.  If you don't want to look it up for yourself, here is
the relevant excerpt:

   FAT is best suited for disk partitions that are 80 MB or less in size
   _or_ that have a limited number of files installed. Usually, 256
   files is a good target, with up to 500 acceptable. [emphasis added]

To quote from another message from you to me in the same packet:

ET> Please at least _read_ the messages you are replying to. :)

    Regards,

        --Murray

___
 * MR/2 2.25 #120 * Nothing is so uncommon as common sense

--- Maximus/2 2.02