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Subject: Re: Ada's Slide To Oblivion ...
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From: Ray Blaak <blaak@telus.net>
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Organization: The Transcend
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Date: 07 Feb 2002 09:25:47 -0800
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Date: 2002-02-07T09:25:47-08:00
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Ian Wild <ian@cfmu.eurocontrol.be> writes:
> C, in practice as well as theory, has two flavours of pointer,
> and there's no operation that will convert between code
> pointers and data pointers.  You simply *can't* read or write
> via code space pointers, nor can you call a data pointer.

You most certainly can:

   void foo()
   {
       typedef void (*FUNC)();
   
       // calling some data
       int i = 0;
       FUNC f = (FUNC) &i;
       f();
   
       // writing some code
       f = foo;
       int *p = (int*) f;
       *p = 2;
   }

That this crashes with access violations on a sane OS is a good thing, but
nothing in the language is preventing the code/data conversions.

-- 
Cheers,                                        The Rhythm is around me,
                                               The Rhythm has control.
Ray Blaak                                      The Rhythm is inside me,
blaak@telus.net                                The Rhythm has my soul.