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Mail Archives: djgpp/1999/10/05/14:18:35

From: "Damian Yerrick" <web DOT poison AT pineight DOT 8m DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: far pointers again
Date: Tue, 5 Oct 1999 10:45:37 -0500
Organization: Rose-Hulman Institute of Technology
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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

David Fokkema wrote:
>
> I think that code like:
>
> i = FARPEEKW(SEL, OFFSET);           <= or something like that
> printf("%d", i);
>
> which results in:
>
> mov ebx,SEL      <= I believe this is what the
> mov es,ebx      <= far pointer functions do.
> mov ebx,OFFSET      <= At least some suggested macros
> mov [ebp-x],word ptr es:[ebx]    <= do.
>
> push word ptr [ebp-x]      <= this is what i remember from
> push dword ptr [y]      <= what i checked already. but i
> call _printf      <= could be incorrect.
>
> is somewhat less efficient than:
>
> printf("%d", *this_is_a_far_pointer);
>
> which results in:
>
> push dword ptr [ebp-z]
> push dword ptr [y]
> call _printf
>
> At least it is programmersfriendlier to code. Why didn't someone take the
> time to implement far pointers for ease of all those apparantly not
totally
> sane people like me who just want to use another segment without having to
> use frustrating macros.

I agree. I liked the way Borland did far pointers. It would make
video access easier and speed porting of legacy real-mode
code. Should some fellow suggest this to the GCC group?



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