From - Mon Oct 27 09:31:07 1997
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From: tguinther@aol.com (Tguinther)
Newsgroups: comp.os.ms-windows.programmer.nt.kernel-mode
Subject: Re: segmented model and NT
Date: 26 Oct 1997 15:52:01 GMT
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>We plan to write a WIN32-Program that allocates memory for the 
>286 program and then uses a kernel driver to  create the needed
>descriptors.
>
>

There was a previous reply to your previous message about the Win16 subsystem
 providing all the
selector routines so I am assuming that your 286 program is not a Win16 client,
 and is just a typical 
286 16:16 executable. If that is the case then you could simply use your
 "device driver" to create and maintain a LDT that contained all the selector
 entries you needed. Assuming you have an LDT then you can *poke* the Win32
 kernel process environment block with the LDT value, and unwittingly,
 ntoskrnl!SwapContext will blindly *poke* that value into the GDT when a thread
 from your process is active.

This is an extreme generalization and it may not be appropriate for what you
 are attending to accomplish. Also, there may be technical difficulties I have
 not taken into account. In reality the Win32 process could provide the LDT
 management itself, and the only real need for the driver is to *poke* the LDT
 into the KPEB.




Tom Guinther,
Vireo Software
tomg@vireo.com
tguinther@aol.com