Date: Fri, 13 Nov 92 09:03:03 EST
From: DJ Delorie <dj AT athena DOT ctron DOT com>
To: acc AT asterix DOT inescn DOT pt
Cc: djgpp AT sun DOT soe DOT clarkson DOT edu

>We are thinking of changing GO32 to support multitasking (preemptive).

Why not just use DESQview/X?  It has all that already.

>* How does VPCI match with multitasking?

It doesn't - that's up to the application.

>* Where should we implement the multitasking kernel:
>  above VPCI or under?

You have no choice - it has to be on the go32 side.

>* Is the 387 emulator reentrant? Will we have problems there?

No, it's not.  You'd have to implement copy-on-write for that portion
of the virtual memory space.

>* The BIOS calls are not reentrant. If we use VPCI will it solve this 
>  problem? And about DOS?

VCPI has nothing to do with it.  When inside a BIOS call, you can't
multitask.  I suggest special-casing certain BIOS calls, like get-key
and get-line, and some read calls, to multitask while waiting for
keyboard input.

DJ
dj AT ctron DOT com
Life is a banana.