Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.1 6/24/83; site ttrdc.UUCP
Path: utzoo!watmath!clyde!cbosgd!ulysses!mhuxr!mhuxn!ihnp4!cuae2!ltuxa!ttrdc!levy
From: levy@ttrdc.UUCP (Daniel R. Levy)
Newsgroups: net.bugs,net.news.b
Subject: Re: 2.10.3 unbatch bug and fix
Message-ID: <806@ttrdc.UUCP>
Date: Fri, 21-Mar-86 14:10:54 EST
Article-I.D.: ttrdc.806
Posted: Fri Mar 21 14:10:54 1986
Date-Received: Sat, 22-Mar-86 22:44:58 EST
References: <243@micropro.UUCP> <9980@ucla-cs.ARPA> <805@ttrdc.UUCP>
Organization: AT&T, Computer Systems Division, Skokie, IL
Lines: 40
Xref: watmath net.bugs:761 net.news.b:1330

In article <805@ttrdc.UUCP>, levy@ttrdc.UUCP (I) wrote:
><Oh oh here it comes.  Watch out boy, it'll chew you up! \
>Oh oh here it comes.  The LINE EATER!  [Line eater]>
>In article <9980@ucla-cs.ARPA>, ekrell@ucla-cs.UUCP writes:
>>In article <243@micropro.UUCP> news@micropro.UUCP (USENET administrator) writes:
>>>< 		while (strncmp(buf, "#! rnews ", 9)
>>>< 			|| strncmp(buf, "! rnews ", 8)) { /* kludge for bug */
>>>---
>>>> 		while (!strncmp(buf, "#! rnews ", 9)
>>>> 			&& !strncmp(buf, "! rnews ", 8)) { /* kludge for bug */
>>
>>Aren't these two the same by De Morgan's law?
>>--
>>    Eduardo Krell               UCLA Computer Science Department
>int A,B;
>
>(A || B) == !(!A && !B);	/* sez demorgans law */
>  A
>    0 1         0 1
>  \_____      \_____
>B 0|0|1|      0|1|0|
>   -----  == ! -----		(Karnaugh map representation)
>  1|1|1|      1|0|0|
>   -----       -----
Sheesh, egg on my face.  Not because this logical assertion is untrue
(it still holds) but because I just realized that the strncmp clauses
above don't make sense!  The first will always be true, the second always
false.  In the first case, there will always be NO MATCH either between
buf and "!# rnews " or buf and "! rnews ".  NO MATCH means a "boolean"
true (nonzero) in strncmp, at least the last time I checked the manual.
The OR of two things, at least one of which is guaranteed to be true, is
therefore itself guaranteed to be true.  Or am I washed up?
-- 
 -------------------------------    Disclaimer:  The views contained herein are
|       dan levy | yvel nad      |  my own and are not at all those of my em-
|         an engihacker @        |  ployer or the administrator of any computer
| at&t computer systems division |  upon which I may hack.
|        skokie, illinois        |
 --------------------------------   Path: ..!{akgua,homxb,ihnp4,ltuxa,mvuxa,
						vax135}!ttrdc!levy