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Net::SMTP - Simple Mail Transfer Protocol Client


use Net::SMTP;

# Constructors
$smtp = Net::SMTP->new('mailhost');
$smtp = Net::SMTP->new('mailhost', Timeout => 60);


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 RFC821.

A new Net::SMTP object must be created with the new method. Once this has been done, all SMTP commands are accessed through this object.

The Net::SMTP class is a subclass of Net::Cmd and IO::Socket::INET.


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";

This example sends a small message to the postmaster at the SMTP server known as mailhost:

#!/usr/local/bin/perl -w

use Net::SMTP;

$smtp = Net::SMTP->new('mailhost');


$smtp->datasend("To: postmaster\n");
$smtp->datasend("A simple test message\n");



new Net::SMTP [ 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.

If HOST is an array reference then each value will be attempted in turn until a connection is made.

If HOST is not given, then the SMTP_Host 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 a guess will be taken.

LocalAddr and LocalPort - These parameters are passed directly to IO::Socket to allow binding the socket to a local port.

Timeout - Maximum time, in seconds, to wait for a response from the SMTP server (default: 120)

ExactAddresses - If true the 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


    $smtp = Net::SMTP->new('mailhost',
			   Hello => 'my.mail.domain'
			   Timeout => 30,
                           Debug   => 1,


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.

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.

etrn ( DOMAIN )

Request a queue run for the DOMAIN given.


Attempt SASL authentication.

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 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>

The Return and Envelope parameters are used for DSN (Delivery Status Notification).

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 some additional OPTIONS which is passed in hash like fashion, using key and value pairs. Possible options are:

Notify    =>
SkipBad   => 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
$smtp->recipient("$recipient,$recipient2"); # BAD   
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. If specified the contents of DATA and a termination string ".\r\n" is sent to the server. And 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.

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.

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.


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 reccomended. The application should really use a module like Mail::Address to extract the mail address and pass that.

If ExactAddresses is passed to the contructor, then addresses should be a valid rfc2821-quoted address, although Net::SMTP will accept accept the address surrounded by angle brackets.

funny user@domain      WRONG
"funny user"@domain    RIGHT, recommended
<"funny user"@domain>  OK




Graham Barr <>


Copyright (c) 1995-1997 Graham Barr. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

$Id: //depot/libnet/Net/ $