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From: dmurdoch@watstat.uwaterloo.ca (Duncan Murdoch)
Newsgroups: comp.os.msdos.programmer
Subject: Re: Virtual Memory for the Heap
Message-ID: <1990Aug6.135207.6581@maytag.waterloo.edu>
Date: 6 Aug 90 13:52:07 GMT
References: <2698@mindlink.UUCP>
Sender: daemon@maytag.waterloo.edu (Admin)
Organization: University of Waterloo
Lines: 21

In article <2698@mindlink.UUCP> a35@mindlink.UUCP (Bruce Atherton) writes:
>The third method, and one I am sorry they didn't include as part of
>VROOMM, would be to use normalized pointers and store the page
>information in the unused part.
...
>
>Why couldn't there be a variant of the Huge memory model called Virtual,
>that used those unused bits to store page information for a memory
>manager?  Some function must be ensuring that the pointers stay
>normalized.  If that function is called whenever a pointer is
>dereferenced, a virtual memory manager would be simple to implement and
>almost invisible to the programmer.
>
>I know, I know.  That ain't the way Turbo C++ works.  Is there anything
>that does, other than Zortech?

Turbo Pascal also uses normalized pointers, and there's a package available
(called HEAP55.xxx for TP 5.5) that calls an interrupt every time a pointer
is dereferenced.  

Duncan Murdoch