> I'm not so sure that what you're looking for is possible.  I did a
> little playing around last evening with a memory scanner, and it
> appears, from my brief testing, that Windows 95/98 replaces
> COMMAND.COM, in whole or in part, while loading.

All DOS apps have the ability to overwrite all but a very small part of
COMMAND.COM in the RAM; this is because COMMAND.COM is split into two parts,
the permanent part loaded by the OS at boot and the transient part (command
line, internal commands etc.).  When a program finishes, control transfers
back to the permanent part of COMMAND.COM, which checks whether the transient
part is intact and if not loads it back off disk.  Those of us who were used
to floppy-only systems back in the day may remember the "Insert disk with
COMMAND.COM and press any key to continue" prompt -- this is the cause of that
message.

Now, I'd guess that Win9x does the same thing -- it has to leave IO.SYS (and
any drivers loaded by CONFIG.SYS and AUTOEXEC.BAT, including HIMEM.SYS) in
RAM, so I'd presume the permanent part of COMMAND.COM stays too.  This is
presumably one copy of COMMAND.COM seen in the MEM /C listing.  Within
Windows, though, this isn't used -- but if the 'DOS mode' option is used and
doesn't require a reboot, it'd be this copy of COMMAND.COM that loads itself
back off disk and runs.

Regards,
Ben A L Jemmett.
(http://web.ukonline.co.uk/ben.jemmett/, http://www.deltasoft.com/)

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