Xref: news2.mv.net comp.os.msdos.djgpp:2319
From: Erik Max Francis <max AT alcyone DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: How to code Interrupts in C?
Date: Sun, 31 Mar 1996 15:53:19 -0800
Organization: Alcyone Systems
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To: djgpp AT delorie DOT com
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GEORGE GAGHON wrote:

> int w_stuff
> long l_stufftoo
> byte b_stuffalso
> 
> w_stuff = *p    <---- will this grab a word at location p
> l_stufftoo = *(p+2)<---- will this grab a long ?
> b_stuffalso = *(p+6) <--- and this will grab a byte, right?

No.  It depends on what kind of pointer p is.  Say that p is declared as a
char *.  Then *p (or, equivalently, p[0]) would get the char at p, *(p + 2)
(or p[2]) would get the char at p + 2, and *(p + 6) (p[6]) would get the char
at p + 6.  Since the pointer is a char * (or whatever), dereferencing it gives
you a char (or whatever).  If you want to dereference to get other values, you
have to explicitly cast it before dereferencing; i.e., *(int *) p.

-- 
Erik Max Francis &tSftDotIotE && http://www.alcyone.com/max && max AT alcyone DOT com
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