Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!usc!ginosko!aplcen!haven!adm!smoke!gwyn
From: gwyn@smoke.BRL.MIL (Doug Gwyn)
Newsgroups: comp.lang.c
Subject: Re: Creating pointer with all bits 0 (was: Referencing NULL pointers)
Message-ID: <10947@smoke.BRL.MIL>
Date: 6 Sep 89 10:14:24 GMT
References: <1989Aug31.052756.18524@sq.sq.com> <2030@se-sd.NCR.COM> <1989Sep6.052228.17374@algor2.algorists.com>
Reply-To: gwyn@brl.arpa (Doug Gwyn)
Organization: Ballistic Research Lab (BRL), APG, MD.
Lines: 8

In article <1989Sep6.052228.17374@algor2.algorists.com> jeffrey@algor2.UUCP (Jeffrey Kegler) writes:
>If I am correct, this could cause problems.  It is not hard to imagine
>an implementation where every possible pointer bit pattern is a valid
>physical address.  No pattern would remain for the null pointer.

I've already explained how an implementation could provide a null
pointer anyway, by using a datum in the run-time library whose address
would be used for null pointers.