Net::SMTP(3pm) Perl Programmers Reference Guide Net::SMTP(3pm)
NAME
Net::SMTP - Simple Mail Transfer Protocol Client
SYNOPSIS
use Net::SMTP;
# Constructors
$smtp = Net::SMTP->new('mailhost');
$smtp = Net::SMTP->new('mailhost', Timeout => 60);
DESCRIPTION
This module implements a client interface to the SMTP and ESMTP
protocol, enabling a perl5 application to talk to SMTP servers. This
documentation assumes that you are familiar with the concepts of the
SMTP protocol described in RFC2821. With IO::Socket::SSL installed it
also provides support for implicit and explicit TLS encryption, i.e.
SMTPS or SMTP+STARTTLS.
The Net::SMTP class is a subclass of Net::Cmd and (depending on
avaibility) of IO::Socket::IP, IO::Socket::INET6 or IO::Socket::INET.
Class Methods
"new([$host][, %options])"
This is the constructor for a new Net::SMTP object. $host is the
name of the remote host to which an SMTP connection is required.
On failure "undef" will be returned and $@ will contain the reason
for the failure.
$host is optional. If $host is not given then it may instead be
passed as the "Host" option described below. If neither is given
then the "SMTP_Hosts" specified in "Net::Config" will be used.
%options are passed in a hash like fashion, using key and value
pairs. Possible options are:
Hello - SMTP requires that you identify yourself. This option
specifies a string to pass as your mail domain. If not given
localhost.localdomain will be used.
SendHello - If false then the EHLO (or HELO) command that is
normally sent when constructing the object will not be sent. In
that case the command will have to be sent manually by calling
"hello()" instead.
Host - SMTP host to connect to. It may be a single scalar
(hostname[:port]), as defined for the "PeerAddr" option in
IO::Socket::INET, or a reference to an array with hosts to try in
turn. The "host" method will return the value which was used to
connect to the host. Format - "PeerHost" from IO::Socket::INET new
method.
Port - port to connect to. Default - 25 for plain SMTP and 465 for
immediate SSL.
SSL - If the connection should be done from start with SSL,
contrary to later upgrade with "starttls". You can use SSL
arguments as documented in IO::Socket::SSL, but it will usually use
the right arguments already.
LocalAddr and LocalPort - These parameters are passed directly to
IO::Socket to allow binding the socket to a specific local address
and port.
Domain - This parameter is passed directly to IO::Socket and makes
it possible to enforce IPv4 connections even if IO::Socket::IP is
used as super class. Alternatively Family can be used.
Timeout - Maximum time, in seconds, to wait for a response from the
SMTP server (default: 120)
ExactAddresses - If true then all $address arguments must be as
defined by "addr-spec" in RFC2822. If not given, or false, then
Net::SMTP will attempt to extract the address from the value
passed.
Debug - Enable debugging information
Example:
$smtp = Net::SMTP->new('mailhost',
Hello => 'my.mail.domain',
Timeout => 30,
Debug => 1,
);
# the same
$smtp = Net::SMTP->new(
Host => 'mailhost',
Hello => 'my.mail.domain',
Timeout => 30,
Debug => 1,
);
# the same with direct SSL
$smtp = Net::SMTP->new('mailhost',
Hello => 'my.mail.domain',
Timeout => 30,
Debug => 1,
SSL => 1,
);
# Connect to the default server from Net::config
$smtp = Net::SMTP->new(
Hello => 'my.mail.domain',
Timeout => 30,
);
Object Methods
Unless otherwise stated all methods return either a true or false
value, with true meaning that the operation was a success. When a
method states that it returns a value, failure will be returned as
undef or an empty list.
"Net::SMTP" inherits from "Net::Cmd" so methods defined in "Net::Cmd"
may be used to send commands to the remote SMTP server in addition to
the methods documented here.
"banner()"
Returns the banner message which the server replied with when the
initial connection was made.
"domain()"
Returns the domain that the remote SMTP server identified itself as
during connection.
"hello($domain)"
Tell the remote server the mail domain which you are in using the
EHLO command (or HELO if EHLO fails). Since this method is invoked
automatically when the Net::SMTP object is constructed the user
should normally not have to call it manually.
"host()"
Returns the value used by the constructor, and passed to
IO::Socket::INET, to connect to the host.
"etrn($domain)"
Request a queue run for the $domain given.
"starttls(%sslargs)"
Upgrade existing plain connection to SSL. You can use SSL
arguments as documented in IO::Socket::SSL, but it will usually use
the right arguments already.
"auth($username, $password)"
"auth($sasl)"
Attempt SASL authentication. Requires Authen::SASL module. The
first form constructs a new Authen::SASL object using the given
username and password; the second form uses the given Authen::SASL
object.
"mail($address[, %options])"
"send($address)"
"send_or_mail($address)"
"send_and_mail($address)"
Send the appropriate command to the server MAIL, SEND, SOML or
SAML. $address is the address of the sender. This initiates the
sending of a message. The method "recipient" should be called for
each address that the message is to be sent to.
The "mail" method can take some additional ESMTP %options which is
passed in hash like fashion, using key and value pairs. Possible
options are:
Size => <bytes>
Return => "FULL" | "HDRS"
Bits => "7" | "8" | "binary"
Transaction => <ADDRESS>
Envelope => <ENVID> # xtext-encodes its argument
ENVID => <ENVID> # similar to Envelope, but expects argument encoded
XVERP => 1
AUTH => <submitter> # encoded address according to RFC 2554
The "Return" and "Envelope" parameters are used for DSN (Delivery
Status Notification).
The submitter address in "AUTH" option is expected to be in a
format as required by RFC 2554, in an RFC2821-quoted form and
xtext-encoded, or <> .
"reset()"
Reset the status of the server. This may be called after a message
has been initiated, but before any data has been sent, to cancel
the sending of the message.
"recipient($address[, $address[, ...]][, %options])"
Notify the server that the current message should be sent to all of
the addresses given. Each address is sent as a separate command to
the server. Should the sending of any address result in a failure
then the process is aborted and a false value is returned. It is up
to the user to call "reset" if they so desire.
The "recipient" method can also pass additional case-sensitive
%options as an anonymous hash using key and value pairs. Possible
options are:
Notify => ['NEVER'] or ['SUCCESS','FAILURE','DELAY'] (see below)
ORcpt => <ORCPT>
SkipBad => 1 (to ignore bad addresses)
If "SkipBad" is true the "recipient" will not return an error when
a bad address is encountered and it will return an array of
addresses that did succeed.
$smtp->recipient($recipient1,$recipient2); # Good
$smtp->recipient($recipient1,$recipient2, { SkipBad => 1 }); # Good
$smtp->recipient($recipient1,$recipient2, { Notify => ['FAILURE','DELAY'], SkipBad => 1 }); # Good
@goodrecips=$smtp->recipient(@recipients, { Notify => ['FAILURE'], SkipBad => 1 }); # Good
$smtp->recipient("$recipient,$recipient2"); # BAD
Notify is used to request Delivery Status Notifications (DSNs), but
your SMTP/ESMTP service may not respect this request depending upon
its version and your site's SMTP configuration.
Leaving out the Notify option usually defaults an SMTP service to
its default behavior equivalent to ['FAILURE'] notifications only,
but again this may be dependent upon your site's SMTP
configuration.
The NEVER keyword must appear by itself if used within the Notify
option and "requests that a DSN not be returned to the sender under
any conditions."
{Notify => ['NEVER']}
$smtp->recipient(@recipients, { Notify => ['NEVER'], SkipBad => 1 }); # Good
You may use any combination of these three values
'SUCCESS','FAILURE','DELAY' in the anonymous array reference as
defined by RFC3461 (see <https://www.ietf.org/rfc/rfc3461.txt> for
more information. Note: quotations in this topic from same.).
A Notify parameter of 'SUCCESS' or 'FAILURE' "requests that a DSN
be issued on successful delivery or delivery failure,
respectively."
A Notify parameter of 'DELAY' "indicates the sender's willingness
to receive delayed DSNs. Delayed DSNs may be issued if delivery of
a message has been delayed for an unusual amount of time (as
determined by the Message Transfer Agent (MTA) at which the message
is delayed), but the final delivery status (whether successful or
failure) cannot be determined. The absence of the DELAY keyword in
a NOTIFY parameter requests that a "delayed" DSN NOT be issued
under any conditions."
{Notify => ['SUCCESS','FAILURE','DELAY']}
$smtp->recipient(@recipients, { Notify => ['FAILURE','DELAY'], SkipBad => 1 }); # Good
ORcpt is also part of the SMTP DSN extension according to RFC3461.
It is used to pass along the original recipient that the mail was
first sent to. The machine that generates a DSN will use this
address to inform the sender, because he can't know if recipients
get rewritten by mail servers. It is expected to be in a format as
required by RFC3461, xtext-encoded.
"to($address[, $address[, ...]])"
"cc($address[, $address[, ...]])"
"bcc($address[, $address[, ...]])"
Synonyms for "recipient".
"data([$data])"
Initiate the sending of the data from the current message.
$data may be a reference to a list or a list and must be encoded by
the caller to octets of whatever encoding is required, e.g. by
using the Encode module's "encode()" function.
If specified the contents of $data and a termination string ".\r\n"
is sent to the server. The result will be true if the data was
accepted.
If $data is not specified then the result will indicate that the
server wishes the data to be sent. The data must then be sent using
the "datasend" and "dataend" methods described in Net::Cmd.
"bdat($data)"
"bdatlast($data)"
Use the alternate $data command "BDAT" of the data chunking service
extension defined in RFC1830 for efficiently sending large MIME
messages.
"expand($address)"
Request the server to expand the given address Returns an array
which contains the text read from the server.
"verify($address)"
Verify that $address is a legitimate mailing address.
Most sites usually disable this feature in their SMTP service
configuration. Use "Debug => 1" option under new() to see if
disabled.
"help([$subject])"
Request help text from the server. Returns the text or undef upon
failure
"quit()"
Send the QUIT command to the remote SMTP server and close the
socket connection.
"can_inet6()"
Returns whether we can use IPv6.
"can_ssl()"
Returns whether we can use SSL.
Addresses
Net::SMTP attempts to DWIM with addresses that are passed. For example
an application might extract The From: line from an email and pass that
to mail(). While this may work, it is not recommended. The application
should really use a module like Mail::Address to extract the mail
address and pass that.
If "ExactAddresses" is passed to the constructor, then addresses should
be a valid rfc2821-quoted address, although Net::SMTP will accept the
address surrounded by angle brackets.
funny user@domain WRONG
"funny user"@domain RIGHT, recommended
<"funny user"@domain> OK
EXAMPLES
This example prints the mail domain name of the SMTP server known as
mailhost:
#!/usr/local/bin/perl -w
use Net::SMTP;
$smtp = Net::SMTP->new('mailhost');
print $smtp->domain,"\n";
$smtp->quit;
This example sends a small message to the postmaster at the SMTP server
known as mailhost:
#!/usr/local/bin/perl -w
use Net::SMTP;
my $smtp = Net::SMTP->new('mailhost');
$smtp->mail($ENV{USER});
if ($smtp->to('postmaster')) {
$smtp->data();
$smtp->datasend("To: postmaster\n");
$smtp->datasend("\n");
$smtp->datasend("A simple test message\n");
$smtp->dataend();
} else {
print "Error: ", $smtp->message();
}
$smtp->quit;
EXPORTS
None.
KNOWN BUGS
See <https://rt.cpan.org/Dist/Display.html?Status=Active&Queue=libnet>.
SEE ALSO
Net::Cmd(3), IO::Socket::SSL(3)
AUTHOR
Graham Barr <gbarr@pobox.com <mailto:gbarr@pobox.com>>.
Steve Hay <shay@cpan.org <mailto:shay@cpan.org>> is now maintaining
libnet as of version 1.22_02.
COPYRIGHT
Copyright (C) 1995-2004 Graham Barr. All rights reserved.
Copyright (C) 2013-2016, 2020 Steve Hay. All rights reserved.
LICENCE
This module is free software; you can redistribute it and/or modify it
under the same terms as Perl itself, i.e. under the terms of either the
GNU General Public License or the Artistic License, as specified in the
LICENCE file.
VERSION
Version 3.13
DATE
23 Dec 2020
HISTORY
See the Changes file.
perl v5.34.0 2021-01-20 Net::SMTP(3pm)
perl 5.34.0 - Generated Thu Mar 3 15:58:17 CST 2022