[comp.os.msdos.misc] Irritating BCX/DOS 5 interaction...

david@compass-da.com (David Hsu) (06/29/91)

I've been playing around with DOS5 for a few days, and have been
pleased with the memory gains by loading stuff high.  However,
I tried to invoke BCX (Borland C++ 2.0's protected mode IDE),
and received an error message saying that it didn't have enough
extended memory to run.  After a couple of hours of massaging
config.sys, rebooting, running MEM, and then invoking BCX
I've come to the following realizations:

 - Only using HIMEM and loading DOS high is OK 
 - Using EMM386 RAM and loading other things high is OK only
     if you specify >800KB to be managed explictly (BCX says
     it needs around 700KB to run).
 - Using EMM386 NOEMS is not OK (BCX says incompatible exp.
     mem. man.).

BCX can use either extended or expanded memory, and it seems
perfectly happy to use extended, but only if EMM386 isn't
around.  With EMM386 loaded, BCX wants expanded, and moans
if there isn't enough.  This seems wasteful to me
(marking almost a fourth of my RAM as expanded solely for BCX),
and Windows reports less available memory as well.  I'm 
nowhere near an authority on DOS, and this situation may
be just the way things are, but it would seem straightforward
to make BCX (or EMM386) smarter.  Am I missing something?
Any cogent observations?  Thanks much in advance for any
enlightenment.

Dave Hsu ({...}!decwrl!vlsisj!david, david@compass-da.com}