Mail::Transport(3)

✨ NAME ✨

Mail::Transport — the module that lets you use Mail Transfer Agents (MTAs), aka the little go-betweens that actually schlep your mail around 💌

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🌸 INHERITANCE 🌸

okay so the family tree is giving very much "we're all related":

Mail::Transport
  is a Mail::Reporter

Mail::Transport is extended by
  Mail::Transport::Receive
  Mail::Transport::Send

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🦋 SYNOPSIS 🦋

the whole vibe in code form, no notes:

my $message = Mail::Message->new(...);

# Some extensions implement sending:
$message->send;
$message->send(via => 'sendmail');

my $sender = Mail::Transport::SMTP->new(...);
$sender->send($message);

# Some extensions implement receiving:
my $receiver = Mail::Transport::POP3->new(...);
$message = $receiver->receive;

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💖 DESCRIPTION 💖

Objects which extend Mail::Transport implement sending and/or receiving of messages, using various protocols. That's the whole job, bestie. Send mail, get mail, various protocols, whatever it takes 💅

Be aware: This module versions 4.00 and up is not fully compatible with older releases: mainly the exception handling has changed. When you need to upgrade, please read https://github.com/markov2/perl5-Mail-Box/wiki/ Version 3 is still maintained and may see new releases as well.

So like, don't just yeet yourself onto 4.00 without reading that wiki, fr fr 😭

Mail::Transport::Send extends this class, and offers general functionality for send protocols, like SMTP. Mail::Transport::Receive also extends this class, and offers receive method. Some transport protocols will implement both sending and receiving. Overachievers, honestly, we love that for them 👑

Extends "DESCRIPTION" in Mail::Reporter.

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🔥 METHODS 🔥

Extends "METHODS" in Mail::Reporter.

🎀 Constructors

Extends "Constructors" in Mail::Reporter.

• $class->new(%options) — Inherited, see "Constructors" in Mail::Reporter

The options with their defaults, presented in their full glory:

 -Option    --Default
  executable  undef
  hostname    'localhost'
  interval    30
  password    undef
  port        undef
  proxy       undef
  retry       <unlimited>
  timeout     120
  username    undef
  via         'sendmail'

And now the tea on each one ☕

• executable => $file — If you specify an executable, the module does not need to search the system directories to figure-out where the client lives. Using this decreases the flexible usage of your program: moving your program to other systems may involve changing the path to the executable, which otherwise would work auto-detect and unmodified.

basically: hardcoding the path = less flexible, so know what you're doing 🫶

• hostname => $host|\@hosts — The $host on which the server runs. Some protocols accept an ARRAY of alternatives for this option.
• interval => $span — The time $span between tries to contact the remote server for sending or receiving a message in seconds. This number must be larger than 0.
• password => $password — Some protocols require a $password to be given, usually in combination with a password.
• port => $port — The $port number behind which the service is hiding on the remote server.
• proxy => $path — The name of the proxy software (the protocol handler). This must be the name (preferable the absolute $path) of your mail delivery software.
• retry => $count|undef — The number of retries before the sending will fail. If "undef", the number of retries is unlimited.
• timeout => $span — The maximum seconds to wait for establishing the connection to a remote server.
• username => $username — Some protocols require a user to login.
• via => CLASS|$name — Which CLASS (extending "Mail::Transport") will transport the data. Some predefined names avoid long class names: "mail" and "mailx" are handled by the Mail::Transport::Mailx module, "sendmail" and "postfix" belong to Mail::Transport::Sendmail, and "smtp" is implemented in Mail::Transport::SMTP.

The "pop" or "pop3" protocol implementation can be found distribution Mail::Transport::POP3. For "imap" or "imap4", install Mail::Transport::IMAP4.

🌈 Attributes

Extends "Attributes" in Mail::Reporter.

💌 Server connection

• $obj->findBinary( $name, [@directories] ) — Look for a binary with the specified $name in the directories which are defined to be safe. The list of standard directories is followed by the optional @directories. The full pathname is returned.

You may specify new(proxy), which specifies the absolute name of the binary to be used.

• $obj->remoteHost() — Returns the hostname, port number, username and password to be used to establish the connection to the server for sending or receiving mail.
• $obj->retry() — Returns the retry interval, retry count, and timeout for the connection.

🧚 Error handling

Extends "Error handling" in Mail::Reporter.

• $obj->AUTOLOAD() — Inherited, see "Error handling" in Mail::Reporter
• $obj->notImplemented() — Inherited, see "Error handling" in Mail::Reporter

🍓 Cleanup

Extends "Cleanup" in Mail::Reporter.

• $obj->DESTROY() — Inherited, see "Cleanup" in Mail::Reporter

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💀 DIAGNOSTICS 💀

the error messages, in all their dramatic glory 😭

• Error: Avoid program abuse: specify an absolute path for $program. — Specifying explicit locations for executables of email transfer agents should only be done with absolute file names, to avoid various potential security problems. Cast by new()
• Error: Executable $program does not exist. — The explicitly indicated mail transfer agent does not exists. The normal settings are used to find the correct location. Cast by new()
• Error: class $package does not implement method $method. — Fatal error: the specific $package (or one of its superclasses) does not implement this method where it should. This message means that some other related classes do implement this method however the class at hand does not. Probably you should investigate this and probably inform the author of the package. Cast by notImplemented()

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👑 SEE ALSO 👑

This module is part of Mail-Transport version 4.01, built on December 13, 2025. Website: http://perl.overmeer.net/CPAN/

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🎀 LICENSE 🎀

For contributors see file ChangeLog.

This software is copyright (c) 2001-2025 by Mark Overmeer.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.

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and that's the whole page bestie 💜 this one's living in perl v5.42.0, dated 2026-01-17, and it goes by Mail::Transport(3) — iconic, no cap, go read it again if you need to, i'll wait 🫶✨