From:	"John M. Aldrich" <fighteer AT cs DOT com>
Newsgroups:	comp.lang.c,comp.os.msdos.djgpp
Subject:	Re: Casting void pointers
Date:	Sun, 21 Jun 1998 22:31:22 -0400
Organization:	Two pounds of chaos and a pinch of salt.
Lines:	33
Message-ID:	<358DC1FA.443E297D@cs.com>
References:	<6mkaos$k7o AT dfw-ixnews6 DOT ix DOT netcom DOT com>
NNTP-Posting-Host:	ppp146.cs.net
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To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Todd Rowan wrote:
> 
> How do you explicity cast a void pointer to a function pointer? Or do you
> even need to cast void pointers manually?

If you want to be able to access the data pointed to by a void pointer,
then you must typecast it to something.  I'm not entirely sure why you'd
want to store a function pointer in a void pointer, but you'd cast it in
the same way that you would declare a function pointer:

#include <stdio.h>

int foo( int x )
{
    return x + 10;
}

int main( void )
{
    void *vp = foo;
    int x = ((int (*)(int)) vp)( 10 );
    printf( "%d\n", x );
    return 0;
}

hth!
-- 
---------------------------------------------------------------------
|      John M. Aldrich       | "Sin lies only in hurting other      |
|       aka Fighteer I       | people unnecessarily.  All other     |
|   mailto:fighteer AT cs DOT com   | 'sins' are invented nonsense."       |
| http://www.cs.com/fighteer |                 - Lazarus Long       |
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