NAME
Mail::EXPN - Perl extension for validation of email addresses
SYNOPSIS
use Mail::EXPN qw(isfake);
$reason = isfake('bill@microsoft.com');
if ($reason) {
print "Bad email: $reason\n";
} elsif (defined($reason)) {
print "Email address perfect\n";
} else {
print "Could not verify email address: EXPN is turned off at target computer";
}
$reason = isfake('bigboss', 'mail.acme.com');
...
DESCRIPTION
This module checks validity of email addresses. It ensure the existence
of a username and domain, unless you specified the MTA, searches the DNS
for the MTA (if not specified), and then attempts to use the SMTP
keyword EXPN to verify the username. Since EXPN is usually turned off,
the module will return *undef* in such cases, and defined but false if
the verification passed. If for any reason the check failed, the module
will return a string describing the reason.
CAVEATS
Contemporary ISPs never turn EXPN on, to prevent mail abusers harass
more efficiently by molesting only existing addresses with junk mail.
Therefore, this is not an excellent solution to check the fill-out forms
in your site for users supplying false email addresses. Most addresses
associated with valid MTAs will return *undef*.
NOTE ON RFC 2821
Mail::EXPN only checks the first mx specified, as it is likely to be the
only one to contain the user list.
TO DO
I tried to rewrite the module using Net::SMTP, but could not figure how
to handle the expand and verify methods. They seemed to return an empty
reply.
CREDITS
Idea by Raz Information Systems, http://www.raz.co.il.
AUTHOR
Ariel Brosh, schop@cpan.org.
MAINTAINER
Florian Helmberger, florian@cpan.org.
VERSION
$Id: README,v 1.2 2003/02/01 10:45:49 florian Exp $
SEE ALSO
perl(1).