KF>> So, if I'm using XMS, is it not going to work on some machines
 KF>> that can otherwise handle EMS? Not that I'm worried too much,
 KF>> but I'd like to know so I'm at least aware of it.
 ml>> in either case, you =must= detect first to see if it's available
 ml>> before attempting to use it... if your program requires EMS and it's
 ml>> not there and you have no other memory access type to use, then you
 ml>> abort with a reason why... same thing with XMS... if it's not
 ml>> available and you require it, abort...
 KF> Yes, I test for it always before trying to use it. But that
 KF> wasn't my question. I already have the answer, I think... EMS
 KF> is available on older machines where XMS may not be, thus since
     ^^^^^^^^^^^^
"=MAY= be available"
 KF> I use XMS it will not be used by my programs on those older
 KF> machines, but EMS could have been had I chosen it instead.
 KF> Does that sound about right?
since both are software driven, either or... yes, EMS was more prevelent back 
in those days... there was even some hardware driven EMS systems... IIRC, 
though, XMS is also available on those systems if there is a driver for it... 
EMS was simply a way for them to access the memory and it was about the 
easiest to implement back then... i'm thinking AT machines... XTs mostly had 
EMS... can't remember if XMS can be done on an XT or not... heck, i've got 
two or three XTs around here... if i can find everything and get them running 
to test with, i may be able to see if DOS 5 or 6 will load HIMEM.SYS for XMS 
access... for some reason, though, i'm thinking it has something to do with 
the A20 address line... i know that QEMM needed it for something... that was 
quite a few years ago... at least 10... hard for me to believe i've been 
doing this stuff for just over 20 years...
)\/(ark
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