Path: utzoo!attcan!utgpu!watmath!att!tut.cis.ohio-state.edu!cs.utexas.edu!uunet!mcsun!ukc!mucs!ian
From: ian@ux.cs.man.ac.uk (Ian Cottam)
Newsgroups: comp.lang.c
Subject: Abandon NULL for (0)
Message-ID: <6502@ux.cs.man.ac.uk>
Date: 20 Sep 89 09:21:12 GMT
Organization: Computer Science, University of Manchester, UK
Lines: 45

Here is a C style suggestion that I am about to adopt (for you to
throw bricks at).  It is related to the issue of silly-little-macros,
but I have decided to use it after following discussions on the net
regarding implementations and users (!) that (re-)define NULL to
something stupid.  The original motivation for writing NULL rather
than 0 was, IMHO, to help the reader of a program text spot where the
denotation 0 meant ``the null pointer''.  I propose that the
integral constant expression

				(0)
be used instead of NULL.

Some example code:

/*
 * Initialise a new stack variable; return false iff init attempt fails
 */
bool
initstack(Stack *s)
{
	extern void *malloc(unsigned int);
	StackHeaderPtr tmp= (StackHeaderPtr)malloc(sizeof(StackHeader));

	if ( (0) == tmp )
		return false; /* malloc failed -- no store */
	else {
		tmp->top= (0); 	/* set stack empty */
		tmp->reserve= (StackElemPtr)malloc(sizeof(StackElem));
		if ( (0) == tmp->reserve )
			return false; /* malloc failure */
		else {
			*s= (Stack)tmp;
			return true;
		}
	}
}


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