From:	Yamaha / XYZZ <scriven AT CS DOT ColoState DOT edu>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: DJGPP-to-Borland Compatibility.
Date:	Thu, 21 Nov 1996 12:23:44 -0700
Organization:	XYZZ Software Co.
Lines:	33
Message-ID:	<3294AC3F.794B@CS.ColoState.edu>
References:	<199611201954 DOT RAA03155 AT cosmos DOT hiway DOT gr>
NNTP-Posting-Host:	seurat.vis.colostate.edu
Mime-Version:	1.0
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Panos Platon Tsapralis wrote:
>         While trying to recompile, using DJGPP, a program, that was originally
> written in Borland-C++, along with some data-base & screen management
> libraries, I encountered error messages that indicate that DJGPP lacks
> functions like "ltoa" ( long-to-ascii ), "ultoa" ( unsigned-long-to-ascii
> ), "MK_FP" ( unknown - could not find in the Borland manuals anything about
> this function ), which admittedly are specific to the Borland's
> implementation of C/C++.

Well, MK_FP not only doesn't exist, but is totally pointless in DJGPP. 
Borland's compiler is a 16-bit Real mode compiler (well, the one I had
was).  DJGPP is a 32-bit Protected mode compiler.  The differences are
largely because of this.

MK_FP in Borland C converts a 16bit pointer to a 32bit segment/offset
pair.  In DJGPP, the pointers are all 32-bit.  You can access up to 4GB
of memory with a pointer, if the memory protection allows it.  (in
borland C, it's only 64k of memory that you can access with a pointer)

DJGPP does support a type of "far" pointers, though.  Protected mode has
"selectors" in the "segment" registers.  If you use a "far" pointer, you
can access memory outside of your regular 4GB area.

ltoa should be replaced by itoa because DJGPP's regular integers are
32-bit, the same size as Borland's long integers.

Anyway, read the FAQ for more/better information.


-- Yamaha / XYZZ
mailto:scriven AT CS DOT ColoState DOT edu          
mailto:scriven AT VIS DOT ColoState DOT edu
http://www.vis.colostate.edu/~scriven/

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