From: krugman AT nospam DOT demon DOT co DOT uk (Kevin)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Generating Machine Code on the fly
Date: Sat, 27 Feb 1999 14:49:36 GMT
Message-ID: <36d80527.13423287@158.152.254.68>
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com

AFIK when you execute a DJGPP compiled program, the Processor is
switched in to protected mode which gives you 
a 32 bit flat address space. this does mean that your machine code has
to take this protected mode in to account. 

I'm a relative Newbie to DJGPP, but if I'm wrong, I'm sure we'll hear
all about it :)

Kevin.

On Fri, 26 Feb 1999 05:45:08 -0000, "Andrew Davidson"
<andrew AT lemure DOT freeserve DOT co DOT uk> wrote:

>
>DJ Delorie <dj AT delorie DOT com> wrote in message
>news:199902270142 DOT UAA26915 AT envy DOT delorie DOT com...
>>
>>> Really? I can malloc 200mb and jump around within that code to my hearts
>>> content? How? Surely I'd have to write my own flat memory mapping code?
>>
>>In djgpp?  No.  It's already taken care of for you.
>
>I don't know if I'm following this but if I'm just pointing the program
>counter at a bunch of bytes djgpp should have nothing whatsoever to do with
>memory mapping. If I'm using the cpu at the lowest possible level (straight
>machine code) doesn't that mean I'm limited to 64k chunks of memory that I
>can write machine code into?
>
>

Kevin.

If you wish to Email or ICQ me, use

kevin AT reality-bytes DOT demon DOT co DOT uk

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