Electronic Mail Processing

This category gathers projects related to various aspects of electronic mail handling.

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Version: 4.2  —  2014-05-23
** New operation mode: proxy

** Command line option precedence

Command line options take precedence over configuration file

** elif statement

A familiar `elif' statement is supported, e.g.:

if condition-1
elif condition-2
elif condition-3
** New CONTROL statement esmtp-auth-delayed.

When set to `yes', this statement instructs Anubis to postpone ESMTP
authentication until MAIL command is issued by the client.  This
allows to change authentication credentials in the SMTP section (see

** SMTP section

The new section "SMTP" is invoked each time an SMTP command
is received. This section may alter the command's argument, using the
"modify command", e.g.:

regex :extended
modify command [ehlo] "foo.bar.net"
if command ["mail from:"] "<(.*)>(.*)"
  modify command ["mail from:"] "<root@bar.net>\2"

It is also allowed to use esmtp-* keywords in this section, provided
that `esmtp-auth-delayed yes' is set in the CONTROL section. Changes
in the ESMTP authentication credentials take effect if they occur
either before receiving MAIL command from the client, or when handling
this command, e.g.:

if command ["mail from:"] "<smith(\+.*)?@@example.net>"
  esmtp-auth-id smith
  esmtp-password guessme
  esmtp-auth no

** New keywords: log-facility and log-tag

** Guile output

By default Scheme's standard error and output ports are redirected to
syslog, using priorities `err' and `warning' correspondingly.

** MySQL options file

When using MySQL for Anubis user database, the database parameters and
access credentials are read from the file /etc/my.cnf, section
"anubis".  Additionally, two URL parameters are provided:
"options-file", which sets the name of the options file, and
"options-group", which sets the name of the group.


An SMTP message submission daemon. It represents an intermediate layer between mail user agent (MUA) and mail transport agent (MTA), receiving messages from the MUA, applying to them a set of predefined changes and finally inserting modified messages into an MTA routing network. The set of changes applied to a message is configurable on a system-wide and per-user basis.

Related projects:


Version: 8.15  —  2022-12-11
* Default MFL source file suffix

The default suffix for MFL files is changed to '.mfl'.  In particular,
the master script file is now "mailfromd.mfl".  This change is
intended to avoid confusion with Metafont files, which have suffix

As of this version, the new suffix is recommended, but not obligatory:
the legacy '.mf' suffix is still supported.  If a file 'X.mfl' is not
found, mailfromd will look for 'X.mf'.

* MFL module search path

MFL modules loaded using the "require" or "import" statements are
looked up in module search path.  Previously, they were searched for
in include search path, which created confusion, since include
search path is intended for use by preprocessor.  To maintain backward
compatibility, if mailfromd is unable to find a module in module
search path, it will retry the search using include path.  This
behavior will be maintained during a transitional period (a couple of
releases), after which searches in include search path will be

* Preprocessor configuration

Use of preprocessor is configured by the following statement in the
main configuration file:

  preprocessor {
    # Enable preprocessor.
    enable yes;
    # Preprocessor command line stub.
    command "m4 -s";
    # Pass current include path to the preprocessor via -I options.
    pass-includes false;
    # Pass to the preprocessor the feature definitions via -D options
    # as well as any -D/-U options from the command line.
    pass-defines true;
    # Name of the preprocessor setup file.  Unless absolute, it is
    # looked up in the include path.
    setup-file "pp-setup";

If preprocessor.pass-includes is true, the preprocessor.command
setting is augmented by zero or more -I options, thereby supplying it
the mailfromd include path.

Furthermore, if preprocessor.pass-defines is set, zero or more
-D options defining optional features are passed to it (e.g.
-DWITH_DKIM) as well as any -D and -U options from the mailfromd
command line.

Unless the value of preprocessor.setup-file begins with a slash,
the file with this name is looked up in the current include search
path.  If found, its absolute name is passed to the preprocessor as
first argument.

If the value begins with a slash, it is passed to the preprocessor
as is.

* New MFL operator: $@

The $@ operator can be used as the last argument in a call to
variadic function from another variadic function.  It passes
all variable arguments supplied to the calling function on to
the function being called.  E.g.:

    func x(...)
      # do something

    func y(string x, ...)

In this example, if "y" is called as y("text", 1, 2, 3) it will call
"x" as x(1, 2, 3).

This operator can also be used with a numeric argument: $@(N).  In
this case, it will remove first N elements from the argument list and
push remaining ones on stack.  This is similar to the 'shift'
operator in other programming languages, e.g.:


* Data types in variadic function declaration

The ellipsis in a variadic function declaration can be preceded by
the data type, e.g.:

  func sum (number ...) returns number

For compatibility with previous versions, if the type is omitted,
string is assumed.

* The void() type cast

The void() type cast can be used around a function call to indicate
that its return value is ignored deliberately.

* mfmod: dynamically loaded modules

This new type of mailfromd modules uses dynamically loaded libraries
to extend the program functionality without having to modify its code.
For a detailed discussion see the manual, section 4.22, "Dynamically
Loaded Modules".

Three mfmods exist at the time of this writing:

  - https://www.gnu.org.ua/software/mfmod_ldap/
    LDAP searches.

  - https://www.gnu.org.ua/software/mfmod_openmetrics
    Open metrics support.

  - https://www.gnu.org.ua/software/mfmod_prce/
    Support for Perl-comparible regular expressions.

* Syntax of special handler definitions

Special handlers ("begin" and "end", in particular) are now defined using
the standard "prog" keyword (similar to milter state handlers):

  prog begin

  prog end

Old syntax is supported for backward compatibility, but causes a
deprecation warning.  Application writers are advised to update their

* New special handlers: startup and shutdown

These two handlers provide global initialization and cleanup routines.
The "startup" handler is run by the master mailfromd process as part
of the startup sequence, before the program starts to serve any milter
requests.  The "shutdown" handler is run when mailfromd is about to

Notice an important differences between "startup"/"shutdown" and
"begin"/"end" special handlers.  The latter are session specific: they
are run at the start and end of a milter session.  The former are
global: they are run at the program startup and shutdown.

The "startup" handler is normally used by mfmod interface modules to
load the corresponding shared library.

* Use of STARTTLS in callout

If TLS is supported by libmailutils, the SMTP callout code will use
STARTTLS when offered by the remote server.  This is controlled by the
smtp-starttls configuration statement.  Its possible values are:

    Never use STARTTLS.

    Always use STARTTLS if offered by the server.

    Use STARTTLS only if MAIL FROM: command failed with the code
    530 (Authorization required).

The default is "ondemand".

* Qualified DBM file names in database configuration

Argument to database.file statement can be prefixed with "database
scheme" to select alternative DBM implementation.  For example:

  database rate {
     file "gdbm://rate.db";

See the manual, section 7.11 "Database Configuration" for details.

* New command line option: --echo

The --echo option allows you to control where the output of the "echo"
statement goes in "run" and "test" modes.  When used without argument
it directs the output to the standard output stream.  If an argument
is supplied (as in: --echo=FILE), the output goes to the named file.
The file will be created if it doesn't exist.  Notice, that in the
latter case, the use of '=' is compulsory (--echo FILE won't work).

* Deprecated configuration statements removed

Deprecated configuration statements `lock-retry-count' and
`lock-retry-timeout' were removed in this version.  Use
the `locking' statement instead, e.g. instead of

  lock-retry-count 10;
  lock-retry-timeout 1;


  locking {
    retry-count 10;
    retry-sleep 1;

* Removed support for obsolete features: legacy GeoIP and DSPAM

Mailfromd is a general-purpose mail filtering daemon for Sendmail, Postfix and MeTA1. It is able to filter both incoming and outgoing messages using criteria of arbitrary complexity, supplied by the administrator in the form of a script file. The daemon interfaces with the MTA using Milter or PMilter protocols.


Version: 3.15  —  2022-04-17
* mbox format: don't count terminating empty line as part of the message

* Improve performance of the Sieve fileinto action

* Improve efficiency of operations on flat mailboxes in append mode

* Bugfixes in quoted-printable and fromrd filters

* Variois fixes in mbox and dotmail format libraries

* Fix compilation with flex version 2.6.1

GNU Mailutils is a swiss army knife of electronic mail handling. It contains a rich set of mail-related utilities and daemons, including pop3d, imap4d, sieve and several domain-specific mail delivery agents.

Related projects:


Version: 1.0  —  2019-08-01
Initial release.

Copyright information:

Copyright (C) 2016-2019 Sergey Poznyakoff

   Permission is granted to anyone to make or distribute verbatim copies
   of this document as received, in any medium, provided that the
   copyright notice and this permission notice are preserved,
   thus giving the recipient permission to redistribute in turn.

   Permission is granted to distribute modified versions
   of this document, or of portions of it,
   under the above conditions, provided also that they
   carry prominent notices stating who last changed them.

Local variables:
mode: outline
paragraph-separate: "[  ]*$"
eval: (add-hook 'write-file-hooks 'time-stamp)
time-stamp-start: "changes. "
time-stamp-format: "%:y-%02m-%02d"
time-stamp-end: "\n"

A flexible mailbox archiver program based on GNU mailutils.

mbar scans the given mailbox folder for mailboxes matching a supplied pattern. For each mailbox found, a set of criteria is applied to its messages. All messages that matched the criteria are then picked and moved to the mailbox of the same name, located in the backup folder. If the destination mailbox doesn’t exist, it is created with the necessary intermediate directories.

Related projects:


Version: 1.0

A simplistic implementation of the SMTP mail transport agent, designed for testing purposes. It behaves almost identically to any real MTA, except that it listens on localhost only and delivers all messages to the given UNIX mailbox file.

Related projects:


Version: 2.1  —  2021-07-01
* Support for Guile 2.2

* Bugfixes

* Improved testsuite


An extendable socket map server with a set of modules and framework for writing new socket maps and testing them.

Related projects:


Version: 3.3  —  2021-02-12
* Fix parsing of po header fields

* Use the Language header instead of Language-Team.

Support for Language-Team and language tables is retained for
backward compatibility.

* Organizational change: repository moved to git

The repository along with links for cloning can be viewed online at

See https://puszcza.gnu.org.ua/git/?group=wyslij-po for instructions.

Wyslij-po runs basic checking on PO files given in the command line and submits them to the Translation Project robot.