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Mail Archives: djgpp/1999/06/07/19:35:26

From: "Michael Stewart" <mike AT reggin DOT freeserve DOT co DOT uk>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: accessing the graphical video memory
Date: Mon, 7 Jun 1999 12:01:44 +0100
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To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp
Reply-To: djgpp AT delorie DOT com

Eli Zaretskii wrote in message ...
>_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.

plus according to the FAQ this method will be slightly quicker.


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