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[Original author here.] Exactly! That (DPMI) is the thing I originally wanted to talk about but I realized I had to clarify many more thoughts first! And I stil
by jmmv 3y ago
[Original author here.] Exactly! That (DPMI) is the thing I originally wanted to talk about but I realized I had to clarify many more thoughts first! And I still have to do the research on DPMI to be able to talk about it :)
- kazinator 3y agoIt would be interesting to understand the Quarterdeck products and how they fit together: the separation between QEMM and QDPMI, and how DESQview worked to enhance DOS with multitasking.
- jesuslop 3y agoI was almost amazed when instead of launching windows 3.1 running win.com one could run Borland DPMI host (that they used in their own 32-bit compiler toolchain), that stayed resident offering its API, and then one could run windows' KRNL386.EXE, that hooked with the DPMI host and booted windows.
- TMWNN 3y agoWhat benefit comes from this?
- jesuslop 3y agoNone concrete I can think about, apart from understanding better the innards of windows boot with a whacky experiment. DPMI was an open spec, so this validated that in principle you could write your own DPMI host to make windows think it was running on top of a protected mode whose view to clients you could control and customize. But again can't answer to what avail.
- WalterBright 3y agoZortech shipped with a compact and fast 32 bit DOS extender called DOSX. It worked like a champ. https://www.digitalmars.com/ctg/dos32.html https://www.digitalmars.com/ctg/dos32.html And supported the 286 DOS extender from Rational Systems.
- mrlonglong 3y agoOh yes, that's right it did. I do remember playing about with that.
- mips_r4300i 3y agoCauseWay DOS Extender was released open source to public domain in 2000, and the source is on GitHub, if you're curious about the implementation. It supports builtin EXE (LE) packing as well.