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From: ralf@nl.cs.cmu.edu (Ralf Brown)
Newsgroups: comp.lang.c
Subject: Re: Absolute addressing in Turbo-C
Message-ID: <23@nl.cs.cmu.edu>
Date: Fri, 14-Aug-87 16:08:22 EDT
Article-I.D.: nl.23
Posted: Fri Aug 14 16:08:22 1987
Date-Received: Sun, 16-Aug-87 03:46:06 EDT
References: <8766@brl-adm.ARPA>
Organization: Carnegie-Mellon University, CS/RI
Lines: 31

In article <8766@brl-adm.ARPA> BREEBAAR%HLERUL5.BITNET@wiscvm.wisc.EDU writes:
>I have to use absolute addressing, because of various buffers and variables
>that both the PGA and I need to access. To illustrate, some of the original
>Turbo Pascal declarations:
>
>  VAR  outBuffer : ARRAY [0..255] OF BYTE ABSOLUTE $C000:$6000;
>       outHead   : BYTE ABSOLUTE $C000:$6300;
>       outTail   : BYTE ABSOLUTE $C000:$6301;
>
>My problem ofcourse is: how do I do this in C? (I am using Turbo-C,
>but have no manual (yet).)
>Firstly I would like to know if Turbo-C has something equivalent to the
>'ABSOLUTE' keyword. Probably not.
>So secondly, I'd like the proper C solution to this.
>
>Leo Breebaart (BREEBAART@HLERUL5.BITNET)
>University of Leiden
>The Netherlands

The proper way to do this in C is to declare the type of the buffer, and then
declare a pointer variable pointing to that type.  The first thing to do before
using the pointer variable is to assign it the address you need your buffers
etc at.  In Turbo C, the proper function is 

	pointer = MK_FP( seg, ofs )

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