Thank you Ed.
Now I know what to look for and avoid.
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>>Thanks for the prompt reply, Ed.
>>
>>>Correct; basically, if Extended EXE,give it 640K of conventional, 15MB of DPMI, or if Standard, 640K conventional and 15MB of EMS, and leave it at that. The DOS Extender used by 2.5 (Watcom) didn't like (didn't understand) too much memory, and handled XMS/DPMI much better than emulated EMS. Standard Edition could only use EMS, and only for buffering.
>>
>>Do you mean 15MB Maximum (like I though 3 or 4MB would be plenty enough)?
>>
>
>Yes, maximum! The problem comes when the address space gets bigger than 16MB...
>
>>>Any other bad surprise?
>>
>>>If you have bit-twiddler PLBs or used .BINs, they'll probably break, too.
>>
>>I use Xitech FoxFix Version 3.53 as a repair tool for damaged databases with SET LIBRARY TO FOXFIX. Do you think that will break?
>>
>
>No clue, but it's a safe bet that if it went down to the metal, it won't like running under NT; if it used standard APIs/DOS functions/BIOS functions, it'll probably work.
>
>By bit-twiddlers, I mean stuff that talks to the raw hardware, absolute byte addresses in the standard BIOS code and other unhealthy, performance-oriented things common in DOS programming, without the intervention of common interfaces (like lots of DOS-based comm apps needed to do to get at interrupt-driven port I/O.)