From:	"François Poirier" <fpoirier AT aei DOT ca>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Pointer to memory
Date:	Sun, 10 Jan 1999 15:50:46 -0500
Organization:	AEI Internet
Lines:	34
Message-ID:	<369912A6.52079EC4@aei.ca>
References:	<36985DB7 DOT C5C7D160 AT 2xtreme DOT net>
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To:	djgpp AT delorie DOT com
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Use this:
#include <crt0.h>

       void * MK_FP (unsigned short seg, unsigned short ofs)
       {
         if ( !(_crt0_startup_flags & _CRT0_FLAG_NEARPTR) )
           if (!__djgpp_nearptr_enable ())
             return (void *)0;
         return (void *) (seg*16 + ofs + __djgpp_conventional_base);
       }

Alex Lowe wrote:

> I am trying to port some code, for reading the fonts in ROM for DOS.
> Anyway, what I need to do is to get the memory location of this... I
> have 2 pointers... segment and offset...
>
> And I want to have the pointers added, for example if the segement is
> 0xAA and the offset is 0x03 then I can make a pointer to 0xAD...
>
> The code I am trying to port looks like this:
>
> char *offset=regs.x.bp;
> char *segment=regs.x.es;
>
> char *font=*MK_FP(segment, offset);
>
> That is the code... the last line is the one I am having trouble with...
> Thanks for the info, I hoped I described this well enough.
>
> -- Alex

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