Replying to a message of Ed Beroset  to All:
 >> I never accepted any statements to the effect that "it is
 >> intuitively obvious" from Mathematics professors, I am not
 >> going to accept them from you :)
 EB> That, IMHO, is exactly as it should be!  There's all the
 EB> more reason you should test this stuff out on your own
 EB> machine so that you can tinker with it yourself.
Send me the pieces so I can assemble a DOS machine, Ed :)
 >> to a full OS/2 installation.. "true" DOS isn't even
 EB> FWIW, TASM, the code I posted last time, a small editor and
 EB> DEBUG will all coexist nicely on a single bootable floppy. 
 EB> :-)
Impractical here; if you check the latest nodelist, you will see why :)
 EB> Unfortunately, without the benefit of the protection of
 EB> protected mode, every minor bug can be potentially lethal
 EB> to the entire system.  A write to an uninitialized pointer,
Which is nothing we haven't already faced in DOS..
 >> Just one question here; suppose you do this after this call
 >> to flatmode:  mov DX,FS mov FS,DX  Does FS still have the 4G
 >> seg limit...?
 EB> you propose, what will happen is that DX will get the value
 EB> 08h (since that was the selector used), and then FS will
 EB> get 08h.  Even though it was already 08h, the reload in
 EB> real mode will cause the base address to be changed in
 EB> exactly the way you'd expect for any other real mode
 EB> segment register load, i.e. 80h will be effectively added
 EB> to any FS-relative address.
You loaded FS with the actual selector, and not the real mode segment 
value???  
 EB> Other questions and answers, possibly to whet your appetite:
Interesting, particularly the one about write-protected segments being still 
valid in realmode.
--- FleetStreet 1.21 NR
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