8 Mailfromd Command Line Syntax

The mailfromd binary is started from the command line using the following syntax (brackets indicate optional parts):

$ mailfromd [options] [asgn] [script]

The meaning of each invocation part is described in the table below:

options

The command line options (see options).

asgn

Sendmail macro assignments. These are currently meaningful only with the --test option (see test mode), but this may change in the future. Each assignment has the form:

var=value

where var is the name of a Sendmail macro and value is the value to be assigned to it.

script

The file name of the filter script, if other than the default one.

8.1 Command Line Options.

8.1.1 Operation Modifiers

--daemon

Run in daemon mode (default).

--run[=start]

Load the script named in the command line and execute the function named start, or ‘main’, if start is not given.

The full invocation syntax for this mode is:

mailfromd [options] --run[=start \
          [macro=value] [file args...]

Its parts are:

options

Any mailfromd options needed to tune its behavior.

start

Start symbol. Defaults to main.

macro=value

Any number of Sendmail macro definitions. macro is the macro name and value is the value to initialize it to.

file

Script file name. If omitted, default script file will be used (see default script file).

args...

Command line arguments that will be pased to the start MFL function as parameters.

The start function must be defined as:

func start (...) returns number

See Run Mode, for a detailed discussion of this feature.

-t[state]

--test[=state]

Run in test mode. See Testing Filter Scripts. Default state is ‘envfrom’. This option implies --stderr (see --stderr).

8.1.2 General Settings

--callout-socket=string

Set socket for the default callout server. This is mainly useful together with the --mtasim option.

--echo

--echo=file

This option controls where the output of the echo statement (see Echo) goes when mailfromd is run in test mode, i.e. using the --test or --run options (see Testing Filter Scripts).

When used without argument it directs the echo output to the standard output stream. If an argument is supplied (second form above), the output goes to the named file. The file will be created if it doesn’t exist. Notice, that the use of ‘=’ is compulsory when specifying an argument. A single dash as a filename means standard output, so that --echo=- and --echo are equivalent.

--foreground

Stay in foreground. When given this option, mailfromd will not disconnect itself from the controlling terminal and will run in the foreground.

-g name

--group=name

Retain the group name when switching to user privileges. See Starting and Stopping.

This option complements the group configuration statement (see group).

--include-path=dir

-I dir

Add the directory dir to the list of directories to be searched for include files (see include search path). This setting affects the #include statement (see include) and is used to locate preprocessor setup file (see Preprocessor). If enabled in the configuration (see pass-includes), directories from the include search path will also be added to the preprocessor command line as additional -I options.

--module-path=dir

-P dir

Add the directory dir to the list of directories searched for MFL module files (see module search path). This setting affects the require and import MFL statements. See Modules.

--mailer=url

-M url

Set the URL of the mailer to use. See Mail Sending Functions.

--mtasim

This option is reserved for use by mtasim (see mtasim).

-O[level]

--optimize[=level]

Set optimization level for code generator. Two levels are implemented: ‘0’, meaning no optimization, and ‘1’, meaning full optimization.

-p string

--port=string

--milter-socket=string

Set communication socket. Overrides the listen configuration statement, which you are advised to use instead (see listen).

--pidfile=file

Set pidfile name. Overrides the pidfile configuration statement, which you are advised to use instead (see pidfile).

--relayed-domain-file=file

Read relayed domains from file. Overrides the relayed-domain-file configuration statement (see relayed-domain-file), which you are advised to use instead. See Avoiding Verification Loops, and the description of relayed function (see relayed) for more information.

--resolv-conf-file=file

Read resolver settings from file, instead of the default /etc/resolv.conf.

--state-directory=dir

Set new program state directory. See Local state directory, for the description of this directory and its purposes. This option overrides the settings of state-directory configuration statement, described in state-directory.

-S ip

--source-ip=ip

Set source address for TCP connections. Overrides the ‘source-ip’ configuration statement, which you are advised to use instead (see source-ip).

-u name

--user name

Switch to this user privileges after startup. Overrides the user configuration file statement, which you are advised to use instead (see user). Default user is ‘mail’.

-v var=value

--variable var=value

Assign value to the global variable var. The variable must be declared in your startup script. See overriding initial values, for a detailed discussion of this option.

8.1.3 Preprocessor Options

Following command line options control the preprocessor feature. See Preprocessor, for a detailed discussion of these.

--no-preprocessor

Do not run the preprocessor.

--preprocessor[=command]

If command is supplied, use it as the external preprocessor instead of the default. This overrides the preprocessor.command setting (see conf-preprocessor).

If used without arguments, forces the use of the configured preprocessor. This form is intended as a way to manually enable the use of the preprocessor if disabled in the configuration.

-D name[=value]

--define=name[=value]

Define a preprocessor symbol name to have a value value. This option is ignored if the preprocessor.pass-defines configuration setting is false.

-U name

--undefine=name

Undefine the preprocessor symbol name. This option is ignored if the preprocessor.pass-defines configuration setting is false.

-E

Stop after the preprocessing stage; do not run the compiler proper. The output is in the form of preprocessed source code, which is sent to the standard output.

8.1.4 Timeout Control

See time interval specification, for information on interval format.

--milter-timeout=interval

Set MTA connection timeout. Overrides milter-timeout statement in the mailfromd configuration file, which you are advised to use instead (see milter-timeout).

8.1.5 Logging and Debugging Options

--location-column

--no-location-column

Mention column number in error messages. See location-column. Use --no-location-column to disable

-d string

--debug=string

Set debugging level. See Logging and Debugging.

--dump-code

Parse and compile the script file and dump the disassembled listing of the produced code to the terminal. See Logging and Debugging.

--dump-grammar-trace

Enable debugging the script file parser. While parsing the file, the detailed dump of the parser states and tokens seen will be output.

--dump-lex-trace

Enable debugging the lexical analyzer. While parsing the script file, the detailed dump of the lexer states and matched rules will be output.

--dump-macros

Show Sendmail macros used in the script file. The macro names are displayed as comma-separated lists, grouped by handler names. See Sendmail, for a detailed description of this option and its usage.

--dump-tree

Parse and compile the script file and dump the parse tree in a printable form to the terminal.

--dump-xref

Print a cross-reference of variables used in the filter script. See Testing Filter Scripts.

-E

Stop after the preprocessing stage; do not run the compiler proper. The output is in the form of preprocessed source code, which is sent to the standard output. See Preprocessor.

--lint

Check script file syntax and exit. If the file is OK, return 0 to the shell, otherwise print appropriate messages to stderr and exit with code 78 (‘configuration error’).

--single-process

Do not fork sub-processes to serve requests. This option is meant to assist in debugging mailfromd. Don’t use it for anything else but for debugging, as it terribly degrades performance!

--stack-trace

--no-stack-trace

Add MFL stack trace information to runtime error output. Overrides stack-trace configuration statement. Use the --no-stack-trace to disable trace information.

See tracing runtime errors, for more information on this feature.

--gacopyz-log=level

Set desired logging level for gacopyz library (see Gacopyz). There are five logging levels. The following table lists them in order of decreasing priority:

fatal

Log fatal errors.

err

Log error messages.

warn

Log warning messages.

info

Log informational messages. In particular, this enables printing messages on each subprocess startup and termination, which look like that:

Apr 28 09:00:11 host mailfromd[9411]: connect
    from 192.168.10.1:50398
Apr 28 09:00:11 host mailfromd[9411]: finishing
    connection

This level can be useful for debugging your scripts.

debug

Log debugging information.

proto

Log Milter protocol interactions. This level prints huge amounts of information, in particular it displays dumps of each Milter packet sent and received.

Although it is possible to set these levels independently of each other, it is seldom practical. Therefore, the option --gacopyz-log=level enables all logging levels from level up. For example, --gacopyz-log=warn enables log levels ‘warn’, ‘err’ and ‘fatal’. It is the default. If you need to trace each subprocess startup and shutdown, set --gacopyz-log=info. Setting the logging level to ‘proto’ can be needed only for Gacopyz developers, to debug the protocol.

See Testing Filter Scripts.

--logger=mech

Set logger mechanism (mech is one of ‘stderr’, ‘syslog’, ‘syslog:async’). See Logging and Debugging.

--log-facility=facility

Output logs to syslog facility.

--log-tag=string

Tag syslog entries with the given string, instead of the program name.

--source-info

--no-source-info

Include C source information in debugging messages. This is similar to setting line-info yes in the debug configuration block (see line-info in GNU Mailutils Manual).

The --no-source-info can be used to cancel the effect of the line-info yes configuration statement.

You do not need this option, unless you are developing or debugging mailfromd.

--syntax-check

Synonym for --lint.

--trace

--no-trace

Enable or disable action tracing. If --trace is given, mailfromd will log all executed actions. See Logging and Debugging.

--trace-program[=string]

Enable program instruction tracing. With this option mailfromd will log execution of every instruction in the compiled filter program. The optional arguments allows to specify a comma-separated list of source code modules for which the tracing is to be enabled, for example --trace-program=bi_io,bi_db enables tracing for functions from modules bi_io.c and bi_db.c (notice, that you need not give file suffixes in string).

This option is useful for debugging mailfromd, but is not advised to use otherwise, since it is very time-costly.

-X

--transcript

--no-transcript

Enable or disable transcript of the SMTP sessions to the log channel. See Logging and Debugging.

--syslog

Selects default syslog mechanism for diagnostic output.

--stderr

Directs all logging to standard output. Similar to --logger=stderr.

--xref

Same as --dump-xref. See Logging and Debugging.

8.1.6 Informational Options

-?

--help

Give a short help summary.

--usage

Give a short usage message.

-V

--version

Print program version.

--show-defaults

Show compilation defaults. See Examining Defaults.

8.2 Starting and Stopping

Right after startup, when mailfromd has done the operations that require root privileges, it switches to the privileges of the user it is configured to run as (see default user privileges) or the one given in its configuration file (see user). During this process it will drop all supplementary groups and switch to the principal group of that user.

Such limited privileges of the daemon can cause difficulties if your filter script needs to access some files (e.g. Sendmail databases) that are not accessible to that user and group. For example, the following fragment using dbmap function:

if dbmap("/etc/mail/aliases.db", $f, 1)
  …
fi

will normally fail, because /etc/mail/aliases.db is readable only to the root and members of the group ‘smmsp’.

In such situations you need to instruct mailfromd to retain the privileges of one or several supplementary groups when switching to the user privileges. This is done using group statement in the mailfromd configuration file (see group). In example above, you need to use the following settings:

group smmsp;

(The same effect can be achieved with --group command line option: mailfromd --group=smmsp).

To stop a running instance of mailfromd use one of the following signals: SIGQUIT, SIGTERM, SIGINT. All three signals have the same effect: the program cancels handling any pending requests, deinitializes the communication socket (if it is a UNIX socket, the program unlinks it) and exits.

To restart the running mailfromd instance, send it SIGHUP. For restart to be possible, two conditions must be met: mailfromd must be invoked with the full file name, and the configuration file name must be full as well. If either of them is not met, mailfromd displays a similar warning message:

warning: script file is given without full file name
warning: restart (SIGHUP) will not work

or:

warning: mailfromd started without full file name
warning: restart (SIGHUP) will not work

The reaction of mailfromd on SIGHUP in this case is the same as on the three signals described previously, i.e. cleanup and exit immediately.

The PID of the master instance of mailfromd is kept on the pidfile, which is named mailfromd.pid and is located in the program state directory. Assuming the default location of the latter, the following command will stop the running instance of the daemon:

kill -TERM `head -n1 /usr/local/var/mailfromd/mailfromd.pid`

The default pidfile location is shown in the output of mailfromd --show-defaults (see Examining Defaults), and can be changed at run time using pidfile statement (see pidfile).

To facilitate the use of mailfromd, it is shipped with a shell script that can be used to launch it on system startup and shut it down when the system goes down. The script, called rc.mailfromd, is located in the directory /etc of the distribution. It takes a single argument, specifying the action that should be taken:

start

Start the program.

stop

Shut down the program

reload

Reload the program, by sending it SIGHUP signal.

restart

Shut down the program and start it again.

status

Display program status. It displays the PID of the master process and its command line, for example:

$ /etc/rc.d/rc.mailfromd status
mailformd appears to be running at 26030
26030 /usr/local/sbin/mailfromd --group smmsp

If the second line is not displayed, this most probably mean that there is a ‘stale’ pidfile, i.e. the one left though the program is not running.

An empty rc.mailfromd status output means that mailfromd is not running.

configtest [file]

Check the script file syntax, report any errors found and exit. If file is given it is checked instead of the default one.

macros [-c] [file]

Parse the script file (or file, if it is given, extract the names of Sendmail macros it uses and generate corresponding export statements usable in the Sendmail configuration file. By default, mc statements are generated. If -c (--cf) is given, the statements for sendmail.cf are output. See the next chapter for the detailed description of this mode.

You can pass any additional arguments to mailfromd by editing ARGS variable near line 22.

The script is not installed by default. You will have to copy it to the directory where your system start-up scripts reside and ensure it is called during the system startup and shut down. The exact instructions on how to do so depend on the operating system you use and are beyond the scope of this manual.