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Re: DOS extension proposal

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Note that not directly doing an INT 21H has an analogy
on the Amiga.

On the Amiga, all system calls are vectored off a
hardcoded address 4.

Which prevents PDOS-generic or some other emulator
from redirecting the syscalls to a different system.

Unless you were to use hardware paging or whatever
to redirect address 4 somewhere else. But I don't want
to rely on such hardware existing, or able to be
implemented (with privilege).

So what I did was create a "new traditional standard"
(basically something that could/should have been done
in the 1980s) where Amiga apps first check register
d6 (there's a bit more to it than that) to see what the
base address is. If d6 is set to some value then use
that, otherwise use the normal address 4. (something
similar to that).

So that gives the ability of a software override.

So it seems I'm trying to construct the 8086 equivalent.
Plus other things all lumped in to one big barrel of
confusion.

BFN. Paul.

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Thread

DOS extension proposal "muta...@gmail.com" <mutazilah@gmail.com> - 2023-05-20 21:07 -0700
  Re: DOS extension proposal "muta...@gmail.com" <mutazilah@gmail.com> - 2023-05-20 22:46 -0700
    Re: DOS extension proposal "muta...@gmail.com" <mutazilah@gmail.com> - 2023-05-20 23:36 -0700
      Re: DOS extension proposal "muta...@gmail.com" <mutazilah@gmail.com> - 2023-05-20 23:45 -0700
        Re: DOS extension proposal "muta...@gmail.com" <mutazilah@gmail.com> - 2023-05-20 23:56 -0700
  Re: DOS extension proposal JJ <jj4public@outlook.com> - 2023-05-21 17:35 +0700
    Re: DOS extension proposal "muta...@gmail.com" <mutazilah@gmail.com> - 2023-05-21 14:23 -0700

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