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Mail Archives: djgpp/1996/05/20/21:01:40

Date: Mon, 20 May 1996 20:58:37 -0400
From: dj (DJ Delorie)
Message-Id: <199605210058.UAA22650@delorie.com>
To: applea AT weiss DOT che DOT utexas DOT edu
CC: djgpp AT delorie DOT com
In-reply-to: <4nqe0f$som@geraldo.cc.utexas.edu> (applea@weiss.che.utexas.edu)
Subject: Re: Making the nearptr hacks use longs.

> unsigned long *videoptr = (unsigned long *)0xA0000;
>       videoptr[4*i + __djgpp_conventional_base] = sbuffptr[i];

Don't forget that C scales your indexes.  The above expression
is equivalent to this:

	*(long *)((char *)videoptr + 16*i + 4*__djgpp_conventional_base)

Figure out the nearptr math first, *then* convert to a long*.

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