20.4 Delivery Agents by Name

As we have shown earlier, the MAILER command is used to enable a class of delivery agents. For example:


This command causes support for the smtp, esmtp, smtp8, dsmtp, and relay delivery agents to be included in your configuration file. Further, the confSMTP_MAILER mc configuration macro can be used to define which one you want to use as your default outbound delivery agent:

define(`confSMTP_MAILER', `dsmtp')

Before you can choose a default, however, you need to know what each delivery agent does and how they differ. In this section, we describe these and all the other standard and special delivery agents. We describe them in alphabetical order, with a convenient summary shown in Table 20-1.

Table 20-1. Delivery agents described by name


Agents declared



cyrus and cyrusbb (cyrus)

Deliver to a local cyrus user. Handles user+where@local.host syntax to the user's IMAP Vmailbox.


cyrusv2 (cyrusv2)

Somewhat like cyrus, but delivers using LMTP via a Unix-domain socket, and requires Cyrus V2.


discard (discard)

Causes the message to be accepted and discarded.


error (error)

Causes the message to be rejected.


fax (fax)

Delivers to a program that handles fax delivery.


*file* and *include* (*file* and *include*)

Performs delivery by appending to a file, and handle delivery through :include: lists.


local (See this section), prog (See this section)

Performs final, local delivery, either to a user's mailbox or through a program.


mail11 (mail11)

Allows use of the mail11 program for delivery to DECnet addresses.


ph (ph)

Delivery is through the phquery program, which looks up user information in the CCSO nameserver database, and then provides appropriate information for delivery (deprecated).


pop (pop)

Delivery for POP users who lack local accounts using MH's spop.


procmail (procmail)

Delivers via procmail, which allows additional processing for local or special delivery needs.


qpage (qpage)

Part of a client/server software package that allows messages to be sent via an alphanumeric pager.


smtp (smtp, etc.), esmtp (See this section), smtp8 (See this section), dsmtp (See this section), and relay (See this section),

The internal SMTP delivery agents.


usenet (usenet)

The usenet delivery agent is used to post messages to the USENET by means of the inews program.


uucp (Section 4.6.1), uucp-old (Section 4.6.1), uucp-new (Section 4.6.2), suucp (Section 4.6.2), uucp-dom (Section 4.6.3), uucp-uudom (Section 4.6.4)

The delivery agents used to send UUCP mail.

    Part I: Build and Install
    Part II: Administration
    Part III: The Configuration File
    Chapter 21. The D (Define a Macro) Configuration Command
    Chapter 24. The O (Options) Configuration Command