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From: tim@amdcad.AMD.COM (Tim Olson)
Newsgroups: comp.lang.c
Subject: Re: Writing readable code (what is NULL)
Message-ID: <17466@amdcad.AMD.COM>
Date: Fri, 10-Jul-87 14:59:14 EDT
Article-I.D.: amdcad.17466
Posted: Fri Jul 10 14:59:14 1987
Date-Received: Sun, 12-Jul-87 11:58:17 EDT
References: <8249@brl-adm.ARPA>
Reply-To: tim@amdcad.UUCP (Tim Olson)
Organization: Advanced Micro Devices, Inc., Sunnyvale, Ca.
Lines: 21

In article <8249@brl-adm.ARPA> Leisner.Henr@Xerox.COM (marty) writes:
>Also, it is bad practice to define NULL to be something memory model
>dependent.  A better practice is:
>
>#define NULL	(char *) 0
>
>This automatically takes care of the sizeof dependencies.  This gets to
>be a major issue when routines are being passed and/or return NULL.

AARRRGH!!!  *PLEASE* people -- we've been over this time after time:

1)	#define NULL 0

2)	When using NULL as a parameter, cast it to the *correct* type

The above definition of NULL will choke on systems which have
different bit patterns for different pointer types.

	-- Tim Olson
	Advanced Micro Devices
	(tim@amdcad.amd.com)