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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Message-ID:	<315F1AEF.5A083C32@alcyone.com>
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To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

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
San Jose, California, U.S.A. && 37 20 07 N 121 53 38 W && the 4th R is respect
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Omnia quia sunt, lumina sunt. && Dominion, GIGO, GOOGOL, Omega, Psi, Strategem
"Out from his breast/his soul went to seek/the doom of the just." -- _Beowulf_

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