Path: utzoo!mnetor!uunet!husc6!bbn!rochester!udel!mmdf
From: dsill@nswc-oas.arpa (Dave Sill)
Newsgroups: comp.sys.amiga
Subject: Re: malloc() prob. on 3.4a
Message-ID: <2095@louie.udel.EDU>
Date: 15 Apr 88 19:30:09 GMT
Sender: mmdf@udel.EDU
Lines: 56

Leo 'Bols Ewhac' Schwab <well!ewhac> writes:
>In article <315@unicom.UUCP> mille_g@unicom.UUCP (Shane 'spin1' Miller) writes:
>>Leo has kind of set a convention of making a lot of intuition funcs() return
>>void -->  void *OpenScreen().  Then in the code he has: s=OpenScreen(&sdef);
>>...
>... I'm casting them to return a void * (pointer to
	 -------
>nothing), which is a generic pointer which can be assigned to any other kind
>of pointer.

You aren't casting them, you're *declaring* them.

Draft proposed ANSI C (section 3.2.2.3 Oct. '86):
"A pointer to `void' may be converted to a pointer to an object of any
type.  A pointer to an object of any type may be converted to a
pointer to `void' and back again; the result shall compare equal to
the original."

That's not exactly a "generic pointer".  It more like a box that can
hold any pointer.

>	You may accuse me of being lazy, but it works, and I think it makes
>my code more readable.

I don't think it improves readability.  It seems to me you have the
choice of doing either:
	Glorp *GetGlorp();
	Glorp a_glorp;

	a_glorp = GetGlorp();
or
	void *GetGlorp();
	Glorp a_glorp;

	a_glorp = GetGlorp();

In my opinion, the first is more readable because GetGlorp() returns a
pointer to a Glorp(), not a pointer to nothingness.  Additionally, the
former works on non-ANSI compilers.

>  Can anyone think of a compelling reason why I should
>explicitly [declare] stuff?

Well, for one thing, `void *' only works with so-called
ANSI-compatible compilers.  Another problem is that you are
redeclaring the Intuition functions, and the dpANS requires all
declarations in scope for a function to match.

You might be able to get away with it, but I don't think it's a good
idea. 

=========
The opinions expressed above are mine.

"The 80x86 world has no excuse for the mess it has gotten itself into."
					-- Doug Gwyn