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Mail Archives: djgpp/1995/01/27/10:49:33

From: "A.Appleyard" <A DOT APPLEYARD AT fs2 DOT mt DOT umist DOT ac DOT uk>
To: djgpp AT sun DOT soe DOT clarkson DOT edu
Date: Fri, 27 Jan 1995 13:04:21 GMT
Subject: Re: V2
Cc: djgpp AT sun DOT soe DOT clarkson DOT edu (DJGPP users list)

I wrote:-
> Please! I have an important Gnu C++ program that absolutely depends on
> knowing what addresses the text screen gets mapped to, as well as in a few
> places needing to know what addresses the physical memory (at least the
> lowest megabyte of RAM) gets mapped to.

kunst AT prl DOT philips DOT nl replied:-
> Don't worry, Anthony! You can poke to your text screen using 'dosmemput
> (buf, size, 0xB8000);'. The same routine can be used for accessing other DOS
> locations. These routines will still work in V2. You can use the 'farptr'
> routines as well. Pieter Kunst.

In my program I have to write to the text screen a LOT. How much longer will
it take using this `dosmemput()' every time, than direct writing to addresses
like I do now? I don't always write to screen as neat whole bufferfuls, but
often one character here, one there. So I declare `unsigned short *screen'
pointing to the start of the text screen. What are these `farptr' routines and
where is information about them? I don't want the supermassive rewrite job on
my program which this change will cause me. Please!!! What <is> the matter
with having the text screen represented as always the same addresses like now??
Ditto with knowing the graphics screen's address. This change will put a
pickaxe handle through a LOT of my and my department's programs that I wrote!!

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