Path: utzoo!attcan!uunet!aplcen!uakari.primate.wisc.edu!sdd.hp.com!elroy.jpl.nasa.gov!jpl-devvax!lwall
From: lwall@jpl-devvax.JPL.NASA.GOV (Larry Wall)
Newsgroups: comp.lang.perl
Subject: Re: Anyone written a mail-server in perl?.
Message-ID: <9789@jpl-devvax.JPL.NASA.GOV>
Date: 3 Oct 90 17:23:51 GMT
References: <1990Sep26.024048.1757@hades.ausonics.oz.au> <1990Oct3.062122.15323@wrl.dec.com>
Reply-To: lwall@jpl-devvax.JPL.NASA.GOV (Larry Wall)
Organization: Jet Propulsion Laboratory, Pasadena, CA
Lines: 16

In article <1990Oct3.062122.15323@wrl.dec.com> vixie@wrl.dec.com (Paul Vixie) writes:
: if ($headers{"reply-to"} ne undef) {
: 	$reply = $headers{"reply-to"};

Note that this is a bit misleading.  Since ne does *string* comparison,
the above is a fancy way to say

    if ($headers{"reply-to"} ne "") {
    	$reply = $headers{"reply-to"};

To actually check for defined-ness, say

    if (defined $headers{"reply-to"}) {
	$reply = $headers{"reply-to"};

Larry