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From: devine@vianet.UUCP (Bob Devine)
Newsgroups: comp.lang.c
Subject: Re: Writing readable code (what is NULL)
Message-ID: <203@vianet.UUCP>
Date: Tue, 14-Jul-87 20:32:14 EDT
Article-I.D.: vianet.203
Posted: Tue Jul 14 20:32:14 1987
Date-Received: Fri, 17-Jul-87 04:04:09 EDT
References: <8249@brl-adm.ARPA>
Organization: Western Digital, Boulder Tech Ctr
Lines: 16

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.

  Don't do this.  For x86 C Compiler memory models, (char*) might be 2,
or 4 bytes depending on the model.  BUT, there is often mixing of models
and there are portability concerns beyond the immediate need.

  Just use 0 for NULL and cast it appropriately.

Bob Devine