From:	Alan Bork <borka AT execpc DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Mem size
Date:	Fri, 09 Oct 1998 16:45:14 -0500
Organization:	Exec-PC BBS Internet - Milwaukee, WI
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To:	djgpp AT delorie DOT com
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> Hi. I'm a newbie to C. I'm learning with a book right now and it's
> getting into pointers. In one program you find  out the address of
> various pointers. In the book it says  that the memory location should
> only be from 0-65,535 however when I try the program in DJGPP I get
> memory addresses of 300000 and above. What's going on?

16 bit code versus 32 bit code.  Your book is reference to the old-school
DOS where pointers where 16 bit [2^16 -- 64KB] (and then some stuff about
segments and so on).  DJGPP produces 32 bit pointers [2^32 -- 4GB].  

That is the short answer.  Others can go on about memory models, protected
mode, segment/offsets versus flat, and so on.

Hope that helps, 

Alan

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