Date: Mon, 7 Jun 1999 13:19:03 +0300 (IDT)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
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To: Michael Stewart <mike AT reggin DOT freeserve DOT co DOT uk>
cc: djgpp AT delorie DOT com
Subject: Re: accessing the graphical video memory
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On Mon, 7 Jun 1999, Michael Stewart wrote:

> I can't see any errors but there is a shorter way of doing it. _dos_ds is
> already predefined as the selector, eg.

_dos_ds provides much less protection, since it spans the entire low 1MB 
(plus 64KB in the HMA).  In contrast, the code posted here creates a 
selector which only includes the video memory, so if you accidentally 
overstep the limits, your program will crash, but the system will be 
protected.  As far as I understand, writing safe code was the whole point 
of using this method in the first place.