From: "Michael Stewart" <mike AT reggin DOT freeserve DOT co DOT uk>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Problem with following code
Date: Thu, 29 Apr 1999 17:12:39 +0100
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com


>This whole thing is an unnecessarily complex way to plot a pixel,
>though. You could rewrite it much more simply as:
>
>   _farpokeb(_dos_ds, 0xA0000+offset, color);


Or for maximum speed, enable near pointers (be careful, enabling near
pointers switches off _ALL_ memory protection in the DOS area!)

The following code is from Brennans page (the Delorie mirror).

#include <sys/nearptr.h>
char *screen;
if (__djgpp_nearptr_enable() == 0) return ERROR; /* could happen */
/* You must recalculate the screen pointer every time you enter this mode
because __djgpp_conventional_base can change when you malloc/new and other
misc stuff. */

screen = 0xa0000 + __djgpp_conventional_base;
screen[0] = 1;
screen[1] = 1;
/* etc. */
__djgpp_nearptr_disable();

Michael Stewart