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Mail Archives: djgpp/1999/09/24/14:16:55

Date: Fri, 24 Sep 1999 12:05:46 -0400
Message-Id: <199909241605.MAA29887@envy.delorie.com>
From: DJ Delorie <dj AT delorie DOT com>
To: djgpp AT delorie DOT com
In-reply-to: <00812b9d.360764bd@usw-ex0107-056.remarq.com> (message from
Clemens Valens on Fri, 24 Sep 1999 07:49:13 -0700)
Subject: Re: Pointers to base memory
References: <19990924095602 DOT 28929 DOT rocketmail AT web1405 DOT mail DOT yahoo DOT com> <00812b9d DOT 360764bd AT usw-ex0107-056 DOT remarq DOT com>
Reply-To: djgpp AT delorie DOT com
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> Where does ((char*)x)[1234] point to for unsigned int x=0?

It points to the 1234'th byte of your program's code, although usually
programs start at byte 4096.  More likely it points into the unmapped
page at the beginning of your program, so you'd get a segfault if you
tried to use it.

Remember, djgpp still uses segments - and your programs are *tiny*
mode.  You need a segment offset to get to memory outside your segment
(like dos memory, video, etc). (unless you use nearptrs, of course).

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