Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: $Revision: 1.6.2.16 $; site ISM780.UUCP
Path: utzoo!watmath!clyde!burl!ulysses!allegra!mit-eddie!think!ISM780!darryl
From: darryl@ISM780.UUCP
Newsgroups: net.lang.c
Subject: Re: Re: how has C bitten you?  (Really,
Message-ID: <30000009@ISM780.UUCP>
Date: Thu, 29-Aug-85 08:48:00 EDT
Article-I.D.: ISM780.30000009
Posted: Thu Aug 29 08:48:00 1985
Date-Received: Sat, 31-Aug-85 08:21:41 EDT
References: <259@watmum.UUCP>
Lines: 19
Nf-ID: #R:watmum:-25900:ISM780:30000009:000:894
Nf-From: ISM780!darryl    Aug 29 08:48:00 1985


[]

One final, subtle, point.  K&R does not guarantee that the *value* 0 is
distinguishable from all other pointers, but rather, that the *constant* 0
is.  That is to say, you may compare against 0 to determine the validity of
a pointer (or assign to guarantee invalidity), but you may not assume that
comparison against (or assignment of) an int variable whose value is 0 will
have the same result.  This picky distinction probably doesn't affect any
of the better known chips, but might be important on a machine where a null
pointer is not a bit string of 0s.

	    --Darryl Richman, INTERACTIVE Systems Corp.
	    ...!cca!ima!ism780!darryl
	    The views expressed above are my opinions only.

P.S.:  I know that this sounds amazing, so look at the top of K&R p190,
under the section 7.7, equality operators (second paragraph), and again
on top of p192, section 7.14, assignment operators.