Xref: utzoo comp.sources.bugs:2483 comp.lang.perl:2050
Path: utzoo!attcan!utgpu!news-server.csri.toronto.edu!clyde.concordia.ca!uunet!mailrus!usenet.ins.cwru.edu!ncoast!allbery
From: allbery@NCoast.ORG (Brandon S. Allbery KB8JRR/KT)
Newsgroups: comp.sources.bugs,comp.lang.perl
Subject: Re: perl 3.0 patch #19
Message-ID: <1990Aug11.154934.17848@NCoast.ORG>
Date: 11 Aug 90 15:49:34 GMT
References: <9097@jpl-devvax.JPL.NASA.GOV>
Reply-To: allbery@ncoast.ORG (Brandon S. Allbery KB8JRR/KT)
Followup-To: comp.sources.bugs
Organization: North Coast Public Access *NIX, Cleveland, OH
Lines: 33

As quoted from <9097@jpl-devvax.JPL.NASA.GOV> by lwall@jpl-devvax.JPL.NASA.GOV (Larry Wall):
+---------------
| System: perl version 3.0
| Patch #: 19
| 
| 	of the available fields.  In unpack, if you precede a field
| 	spec with %<n>, it does an n-bit checksum on it instead of the
| 	value itself.  (Thus "%16C*" will checksum just like the Sys V sum
| 	program.)  One totally wacked out evening I hacked a u format
| 	in to pack and unpack uudecode-style strings.
+---------------

You're feverish --- go take a nap.  ;-)

+---------------
| 	If errno == 0, the $! variable returned "Error 0" in a string
| 	context, which is, unfortunately, a true string.  It now returns ""
| 	in string context if errno == 0, so you can use it reasonable in
| 	a conditional without comparing it to 0:  &cleanup if $!;
+---------------

I posted about this before, but our news system was hosed so it didn't get out.

I disapprove of this change.  errno is *not* a good way to check for an error;
what will someone do if there was no error but ($! + 0) == ENOTTY because of
stdio?  This is a classic C logic error, and this change legitimizes it as a
Perl paradigm even though it is still a logic error.  IMHO, of course.

++Brandon
-- 
Me: Brandon S. Allbery			    VHF: KB8JRR/KT on 220 (soon others)
Internet: allbery@NCoast.ORG		    Delphi: ALLBERY
uunet!usenet.ins.cwru.edu!ncoast!allbery    America OnLine: KB8JRR