From:	"dima 3141596" <dima AT rts-ukraine DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: addressing question
Date:	Thu, 13 Sep 2001 16:49:34 +0300
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To:	djgpp AT delorie DOT com
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Reply-To:	djgpp AT delorie DOT com

Hi Eli !

>You can't, not with DJGPP: ES and DS are segment registers, and in
>protected mode they can only be loaded with valid segment selectors,
not
>with any arbitrary number.  If you load a value that is not a valid
>selector, your program will get a GPF and crash.
>
>Why do you need to do that, anyway?

 Ok, I have GDT with 3 valid entries: code segment, data segment and
data segment pointed to video RAM (0x0b8000).
 Than I switch to PM and  load CS <- entry 1,  DS <- entry 2,  ES <-
entry 3.
After it I want output any information to the screen:  mov ES:[...], x
in     assembler :).
How can I make it in the DJGPP ?
In the Turbo C I can do  it :     char far* scr = MK_FP(segment,
offset);
 then any instruction like it:       *scr = '1';  will generate asm code
           mov ax,segment
           mov es,ax
           mov  es:[offset] , '1'   ------> here ES !!!

but djgpp has not  far* !!!

I try functions described in the farptr.h. It's work but I want to use C
POINTERS !!!

 --dima

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