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PROCMAIL(1) General Commands Manual PROCMAIL(1)

NAME

procmail - autonomous mail processor

SYNOPSIS

procmail [-ptoY] [-f fromwhom] [parameter=value | rcfile] ...
procmail [-toY] [-f fromwhom] [-a argument] ... -d recipient ...
procmail [-ptY] -m [parameter=value] ... rcfile [argument] ...
procmail [-toY] [-a argument] -z
procmail -v

DESCRIPTION

For a quick start, see NOTES at the end.

Procmail should be invoked automatically over the .forward file mechanism as soon as mail arrives. Alternatively, when installed by a system administrator (and in the standard Red Hat Linux configuration), it can be invoked from within the mailer immediately. When invoked, it first sets some environment variables to default values, reads the mail message from stdin until an EOF, separates the body from the header, and then, if no command line arguments are present, it starts to look for a file named $HOME/.procmailrc. According to the processing recipes in this file, the mail message that just arrived gets distributed into the right folder (and more). If no rcfile is found, or processing of the rcfile falls off the end, procmail will store the mail in the default system mailbox.

If no rcfiles and no -p have been specified on the command line, procmail will, prior to reading $HOME/.procmailrc, interpret commands from /etc/procmailrc (if present). Care must be taken when creating /etc/procmailrc, because, if circumstances permit, it will be executed with root privileges (contrary to the $HOME/.procmailrc file of course).

If running suid root or with root privileges, procmail will be able to perform as a functionally enhanced, backwards compatible mail delivery agent.

Procmail can also be used as a general purpose mail filter, i.e., provisions have been made to enable procmail to be invoked in a special sendmail rule.

The rcfile format is described in detail in the procmailrc(5) man page.

The weighted scoring technique is described in detail in the procmailsc(5) man page.

Examples for rcfile recipes can be looked up in the procmailex(5) man page.

Signals

Terminate prematurely and requeue the mail.
Terminate prematurely and bounce the mail.
Terminate prematurely and bounce the mail.
Terminate prematurely and silently lose the mail.
Force a timeout (see TIMEOUT).
Equivalent to a VERBOSE=off.
Equivalent to a VERBOSE=on.

OPTIONS

Procmail will print its version number, display its compile time configuration and exit.
Preserve any old environment. Normally procmail clears the environment upon startup, except for the value of TZ. However, in any case: any default values will override any preexisting environment variables, i.e., procmail will not pay any attention to any predefined environment variables, it will happily overwrite them with its own defaults. For the list of environment variables that procmail will preset see the procmailrc(5) man page. If both -p and -m are specified, the list of preset environment variables shrinks to just: LOGNAME, HOME, SHELL, ORGMAIL and MAILDIR.
Make procmail fail softly, i.e., if procmail cannot deliver the mail to any of the destinations you gave, the mail will not bounce, but will return to the mailqueue. Another delivery-attempt will be made at some time in the future.
Causes procmail to regenerate the leading `From ' line with fromwhom as the sender (instead of -f one could use the alternate and obsolete -r). If fromwhom consists merely of a single `-', then procmail will only update the timestamp on the `From ' line (if present, if not, it will generate a new one).
Instead of allowing anyone to generate `From ' lines, simply override the fakes.
Assume traditional Berkeley mailbox format, ignore any Content-Length: fields.
This will set $1 to be equal to argument. Each succeeding -a argument will set the next number variable ($2, $3, etc). It can be used to pass meta information along to procmail. This is typically done by passing along the $@x information from the sendmail mailer rule.
This turns on explicit delivery mode, delivery will be to the local user recipient. This, of course, only is possible if procmail has root privileges (or if procmail is already running with the recipient's euid and egid). Procmail will setuid to the intended recipients and delivers the mail as if it were invoked by the recipient with no arguments (i.e., if no rcfile is found, delivery is like ordinary mail). This option is incompatible with -p.
Turns procmail into a general purpose mail filter. In this mode one rcfile must be specified on the command line. After the rcfile, procmail will accept an unlimited number of arguments. If the rcfile is an absolute path starting with /etc/procmailrcs/ without backward references (i.e. the parent directory cannot be mentioned) procmail will, only if no security violations are found, take on the identity of the owner of the rcfile (or symbolic link). For some advanced usage of this option you should look in the EXAMPLES section below.
This turns on LMTP mode, wherein procmail acts as an RFC2033 LMTP server. Delivery takes place in the same manner and under the same restrictions as the delivery mode enabled with -d. This option is incompatible with -p and -f.

ARGUMENTS

Any arguments containing an '=' are considered to be environment variable assignments, they will all be evaluated after the default values have been assigned and before the first rcfile is opened.

Any other arguments are presumed to be rcfile paths (either absolute, or if they start with `./' relative to the current directory; any other relative path is relative to $HOME, unless the -m option has been given, in which case all relative paths are relative to the current directory); procmail will start with the first one it finds on the command line. The following ones will only be parsed if the preceding ones have a not matching HOST-directive entry, or in case they should not exist.

If no rcfiles are specified, it looks for $HOME/.procmailrc. If not even that can be found, processing will continue according to the default settings of the environment variables and the ones specified on the command line.

EXAMPLES

Examples for rcfile recipes can be looked up in the procmailex(5) man page. A small sample rcfile can be found in the NOTES section below.

Skip the rest of this EXAMPLES section unless you are a system administrator who is vaguely familiar with sendmail.cf syntax.

The -m option is typically used when procmail is called from within a rule in the sendmail.cf file. In order to be able to do this it is convenient to create an extra `procmail' mailer in your sendmail.cf file (in addition to the perhaps already present `local' mailer that starts up procmail). To create such a `procmail' mailer I'd suggest something like:

Mprocmail, P=/usr/bin/procmail, F=mSDFMhun, S=11, R=21,


        A=procmail -m $h $g $u


This enables you to use rules like the following (most likely in
    ruleset 0) to filter mail through the procmail mailer (please note the
    leading tab to continue the rule, and the tab to separate the comments):






R$*<@some.where>$*


        $#procmail $@/etc/procmailrcs/some.rc $:$1@some.where.procmail$2
R$*<@$*.procmail>$*


        $1<@$2>$3       Already filtered, map back






And /etc/procmailrcs/some.rc could be as simple as:






SENDER = "<$1>"                 # fix for empty sender addresses
SHIFT = 1                       # remove it from $@
:0                              # sink all junk mail
* ^Subject:.*junk
/dev/null
:0 w                            # pass along all other mail
! -oi -f "$SENDER" "$@"






Do watch out when sending mail from within the
    /etc/procmailrcs/some.rc file, if you send mail to addresses which match the
    first rule again, you could be creating an endless mail loop.
  








FILES



  
/etc/passwd

  
to set the recipient's LOGNAME, HOME and SHELL variable defaults
    

  

  
/var/spool/mail/$LOGNAME

  
system mailbox; both the system mailbox and the immediate directory it is
      in will be created every time procmail starts and either one is not
      present
    

  

  
/etc/procmailrc

  
initial global rcfile
    

  

  
/etc/procmailrcs/

  
special privileges path for rcfiles
    

  

  
$HOME/.procmailrc

  
default rcfile
    

  

  
/var/spool/mail/$LOGNAME.lock

  
lockfile for the system mailbox (not automatically used by procmail,
      unless $DEFAULT equals /var/spool/mail/$LOGNAME and procmail is delivering
      to $DEFAULT)
    

  

  
/usr/sbin/sendmail

  
default mail forwarder
    

  

  
_????`hostname`

  
temporary `unique' zero-length files created by procmail
    

  








SEE ALSO


procmailrc(5), procmailsc(5), procmailex(5),
    sh(1), csh(1), mail(1), mailx(1),
    binmail(1), uucp(1), aliases(5), sendmail(8),
    egrep(1), grep(1), biff(1), comsat(8),
    lockfile(1), formail(1), cron(1)






DIAGNOSTICS



  

  
The system mailbox had its suid or sgid bit set, procmail terminates with
      EX_NOUSER assuming that this mailbox must not be delivered to.
    

  

  

  
Not a valid environment variable name specified.
    

  

  

  
There was no corresponding opening brace (nesting block).
    

  

  

  
Not all option combinations are useful
    

  

  

  
Flag x is not compatible with some other flag on this recipe.
    

  

  

  
The system mailbox was missing and could not/will not be created.
    

  

  

  
The maildir folder "x" is missing one or more required
      subdirectories and procmail could not create them.
    

  

  

  
An error occurred in the mechanics of delivering to the directory folder
      "x".
    

  

  

  
There were no `>>' redirectors to be found, using simply `$LOCKEXT'
      as locallockfile.
    

  

  

  
Procmail was unable to open an rcfile or it was not a regular file, or
      procmail couldn't open an MH directory to find the highest numbered file.
    

  

  

  
Lockfile was already gone, or write permission to the directory where the
      lockfile is has been denied.
    

  

  

  
The locallockfile specified on this recipe is equal to a still active
      $LOCKFILE.
    

  

  

  
Procmail will not take on the identity that comes with the rcfile because
      a security violation was found (e.g. -p or variable assignments on
      the command line) or procmail had insufficient privileges to do so.
    

  

  

  
As procmail was started, stdin, stdout or stderr was not connected
      (possibly an attempt to subvert security)
    

  

  

  
The system mailbox of the recipient was found to be unsecured, procmail
      secured it.
    

  

  

  
Nonexistent subdirectory, no write permission, pipe died or disk full.
    

  

  

  
Buffer overflow detected, LINEBUF was too small, PROCMAIL_OVERFLOW has
      been set.
    

  

  

  

    

  

  

  

    

  

  

  

    

  

  

  

    

  

  

  

    

  

  

  
The specified item's full path, when expanded, was longer than LINEBUF or
      didn't start with a file separator.
    

  

  

  
The program or filter "x" tried to produce too much output for
      the current LINEBUF, the rest was discarded and PROCMAIL_OVERFLOW has been
      set.
    

  

  

  
The action line or other flags on this recipe makes flag x meaningless.
    

  

  

  
Process table is full (and NORESRETRY has been exhausted).
    

  

  

  
Program not in path, or not executable.
    

  

  

  
No write permission in the directory where lockfile "x"
      resides, or more than one procmail trying to force a lock at exactly the
      same time.
    

  

  

  
Lockfile "x" is going to be removed by force because of a
      timeout (see also: LOCKTIMEOUT).
    

  

  

  
The start of a recipe was found, but it stranded in an EOF.
    

  

  

  
Procmail either needs root privileges, or must have the right (e)uid
      and (e)gid to run in delivery mode. The mail will bounce.
    

  

  

  
The regular expression "x" contains errors (most likely some
      missing or extraneous parens).
    

  

  

  
While trying to use the kernel-supported locking calls, one of them failed
      (usually indicates an OS error), procmail ignores this error and proceeds.
    

  

  

  
See above.
    

  

  

  
Can only occur if you specify some real weird (and illegal) lockfilenames
      or if the lockfile could not be created because of insufficient
      permissions or nonexistent subdirectories.
    

  

  

  
Procmail tried to clone itself but could not find back rcfile
      "x" (it either got removed or it was a relative path and you
      changed directory since procmail opened it last time).
    

  

  

  
The current recipe was found to be incomplete.
    

  

  

  
A nesting block was started, but never finished.
    

  

  

  
The -f option needs an extra argument.
    

  

  

  
You specified the -a option but forgot the argument.
    

  

  

  
You specified the -m option, procmail expects the name of an rcfile as
      argument.
    

  

  

  
You specified the -d option or called procmail under a different name, it
      expects one or more recipients as arguments.
    

  

  

  
The filesystem containing "x" does not have enough free space to
      permit delivery of the message to the file.
    

  

  

  
The system is out of swap space (and NORESRETRY has been exhausted).
    

  

  

  
The unrecognised options on the command line are ignored, proceeding as
      usual.
    

  

  

  
Program that was started by procmail returned nnn instead of EXIT_SUCCESS
      (=0); if nnn is negative, then this is the signal the program died on.
    

  

  

  
The filesize quota for the recipient on the filesystem containing
      "x" does not permit delivering the message to the file.
    

  

  

  
The system mailbox of the recipient was found to be bogus, procmail
      performed evasive actions.
    

  

  

  
A filter returned unsuccessfully, procmail tried to get back the original
      text.
    

  

  

  
Couldn't do anything with "x" in the rcfile (syntax error),
      ignoring it.
    

  

  

  
The owner of the rcfile was not the recipient or root, the file was world
      writable, or the directory that contained it was world writable, or this
      was the default rcfile ($HOME/.procmailrc) and either it was group
      writable or the directory that contained it was group writable (the rcfile
      was not used).
    

  

  

  
Procmail received a signal while it was waiting for ...
    

  

  

  
Timeout has occurred on program or filter "x".
    

  

  

  
Timeout has occurred on program, filter or file "x". If it was a
      program or filter, then it didn't seem to be running anymore.
    

  

  

  
The file could not be delivered to successfully, so the file was truncated
      to its former size.
    

  

  

  
"x" does not seem to be a valid filename or the file is not
      empty.
    

  

  

  
Either the suffix on "x" would indicate that it should be an MH
      or maildir folder, or it was listed as an second folder into which to
      link, but it already exists and is not a directory.
    

  

  

  
Missing closing quote, or trying to escape EOF.
    

  

  

  
The specified recipient does not have a corresponding uid.
    

  








EXTENDED DIAGNOSTICS


Extended diagnostics can be turned on and off through setting the
    VERBOSE variable.
  





  
[pid] time & date

  
Procmail's pid and a timestamp. Generated whenever procmail logs a
      diagnostic and at least a second has elapsed since the last timestamp.
    

  

  

  
Procmail now tries to kernel-lock the most recently opened file
      (descriptor).
    

  

  

  
Environment variable assignment.
    

  

  

  
Dropping all privileges (if any), implicitly turns off extended
      diagnostics.
    

  

  

  
The mail spool directory was not accessible to procmail, it relied solely
      on kernel locks.
    

  

  

  
Starting program "x". If it is started by procmail directly
      (without an intermediate shell), procmail will show where it separated the
      arguments by inserting commas.
    

  

  

  
This host was called "x", HOST contained something else.
    

  

  

  
Creating lockfile "x".
    

  

  

  
Creating a hardlink between directory folders.
    

  

  

  
Condition matched.
    

  

  

  
Assigned "x" to MATCH.
    

  

  

  
Condition didn't match, recipe skipped.
    

  

  

  
Program that was started by procmail as a condition or as the action of a
      recipe with the `W' flag returned nnn instead of EXIT_SUCCESS (=0); the
      usage indicates that this is not an entirely unexpected condition.
    

  

  

  
Sent comsat/biff a notice that mail arrived for user $LOGNAME at `offset'
      in `file'.
    

  

  

  
Opening file "x" for appending.
    

  

  

  
Rcfile changed to "x".
    

  

  

  
While attempting several locking methods, one of these failed. Procmail
      will reiterate until they all succeed in rapid succession.
    

  

  

  
This condition scored `added' points, which resulted in a `newtotal'
      score.
    

  

  

  
Removing lockfile "x" again.
    

  








WARNINGS


You should create a shell script that uses lockfile(1)
    before invoking your mail shell on any mailbox file other than the system
    mailbox (unless of course, your mail shell uses the same lockfiles (local or
    global) you specified in your rcfile).


In the unlikely event that you absolutely need to kill procmail
    before it has finished, first try and use the regular kill command (i.e.,
    not kill -9, see the subsection Signals for suggestions),
    otherwise some lockfiles might not get removed.


Beware when using the -t option, if procmail repeatedly is
    unable to deliver the mail (e.g., due to an incorrect rcfile), the system
    mailqueue could fill up. This could aggravate both the local postmaster and
    other users.


The /etc/procmailrc file might be executed with root
    privileges, so be very careful of what you put in it. SHELL will be
    equal to that of the current recipient, so if procmail has to invoke the
    shell, you'd better set it to some safe value first. See also :
    DROPPRIVS.


Keep in mind that if chown(1) is permitted on files in
    /etc/procmailrcs/, that they can be chowned to root (or anyone else)
    by their current owners. For maximum security, make sure this directory is
    executable to root only.


Procmail is not the proper tool for sharing one mailbox among many
    users, such as when you have one POP account for all mail to your domain. It
    can be done if you manage to configure your MTA to add some headers with the
    envelope recipient data in order to tell Procmail who a message is for, but
    this is usually not the right thing to do. Perhaps you want to investigate
    if your MTA offers `virtual user tables', or check out the `multidrop'
    facility of Fetchmail.
  








BUGS


After removing a lockfile by force, procmail waits $SUSPEND
    seconds before creating a new lockfile so that another process that decides
    to remove the stale lockfile will not remove the newly created lock by
    mistake.


Procmail uses the regular TERMINATE signal to terminate any
    runaway filter, but it does not check if the filter responds to that signal
    and it only sends it to the filter itself, not to any of the filter's
    children.


A continued Content-Length: field is not handled
  correctly.


The embedded newlines in a continued header should be skipped when
    matching instead of being treated as a single space as they are now.
  








MISCELLANEOUS


If there is an existing Content-Length: field in the header
    of the mail and the -Y option is not specified, procmail will trim
    the field to report the correct size. Procmail does not change the
    fieldwidth.


If there is no Content-Length: field or the -Y
    option has been specified and procmail appends to regular mailfolders, any
    lines in the body of the message that look like postmarks are prepended with
    `>' (disarms bogus mailheaders). The regular expression that is used to
    search for these postmarks is:




`\nFrom '






If the destination name used in explicit delivery mode is not in
    /etc/passwd, procmail will proceed as if explicit delivery mode was not in
    effect. If not in explicit delivery mode and should the uid procmail is
    running under, have no corresponding /etc/passwd entry, then HOME will
    default to /, LOGNAME will default to #uid, SHELL will default to /bin/sh,
    and ORGMAIL will default to /tmp/dead.letter.


When in explicit delivery mode, procmail will generate a leading
    `From ' line if none is present. If one is already present procmail will
    leave it intact. If procmail is not invoked with one of the following user
    or group ids : root, daemon, uucp, mail, x400, network, list, slist, lists
    or news, but still has to generate or accept a new `From ' line, it will
    generate an additional `>From ' line to help distinguish fake mails.


For security reasons procmail will only use an absolute or
    $HOME-relative rcfile if it is owned by the recipient or root, not world
    writable, and the directory it is contained in is not world writable. The
    $HOME/.procmailrc file has the additional constraint of not being
    group-writable or in a group-writable directory.


If /var/spool/mail/$LOGNAME is a bogus mailbox (i.e., does not
    belong to the recipient, is unwritable, is a symbolic link or is a hard
    link), procmail will upon startup try to rename it into a file starting with
    `BOGUS.$LOGNAME.' and ending in an inode-sequence-code. If this turns out to
    be impossible, ORGMAIL will have no initial value, and hence
    will inhibit delivery without a proper rcfile.


If /var/spool/mail/$LOGNAME already is a valid mailbox, but has
    got too loose permissions on it, procmail will correct this. To prevent
    procmail from doing this make sure the u+x bit is set.


When delivering to directories, MH folders, or maildir folders,
    you don't need to use lockfiles to prevent several concurrently
    running procmail programs from messing up.


Delivering to MH folders is slightly more time consuming than
    delivering to normal directories or mailboxes, because procmail has to
    search for the next available number (instead of having the filename
    immediately available).


On general failure procmail will return EX_CANTCREAT, unless
    option -t is specified, in which case it will return EX_TEMPFAIL.


To make `egrepping' of headers more consistent, procmail
    concatenates all continued header fields; but only internally. When
    delivering the mail, line breaks will appear as before.


If procmail is called under a name not starting with `procmail'
    (e.g., if it is linked to another name and invoked as such), it comes up in
    explicit delivery mode, and expects the recipients' names as command line
    arguments (as if -d had been specified).


Comsat/biff notifications are done using udp. They are sent off
    once when procmail generates the regular logfile entry. The notification
    messages have the following extended format (or as close as you can get when
    final delivery was not to a file):




$LOGNAME@offset_of_message_in_mailbox :absolute_path_to_mailbox






Whenever procmail itself opens a file to deliver to, it
    consistently uses the following kernel locking strategies :
  fcntl(2).


Procmail is NFS-resistant and eight-bit clean.
  








NOTES


Calling up procmail with the -h or -? options will cause it to
    display a command-line help and recipe flag quick-reference page.


There exists an excellent newbie FAQ about mailfilters (and
    procmail in particular); it is maintained by Nancy McGough
    <nancym@ii.com> and can be obtained by sending a mail to
    mail-server@rtfm.mit.edu with the following in the body:




send usenet/news.answers/mail/filtering-faq






If procmail is not installed globally as the default mail
    delivery agent (ask your system administrator), you have to make sure it is
    invoked when your mail arrives. In this case your $HOME/.forward (beware, it
    has to be world readable) file should contain the line below. Be sure
    to include the single and double quotes, and unless you know your site to be
    running smrsh (the SendMail Restricted SHell), it must be an absolute
    path.




" |exec /usr/bin/procmail"


Some mailers (notably exim) do not currently accept the above
    syntax. In such case use this instead:




|/usr/bin/procmail


Procmail can also be invoked to postprocess an already filled
    system mailbox. This can be useful if you don't want to or can't use a
    $HOME/.forward file (in which case the following script could periodically
    be called from within cron(1), or whenever you start reading
  mail):






#!/bin/sh
ORGMAIL=/var/spool/mail/$LOGNAME
if cd $HOME &&


 test -s $ORGMAIL &&


 lockfile -r0 -l1024 .newmail.lock 2>/dev/null
then


  trap "rm -f .newmail.lock" 1 2 3 13 15


  umask 077


  lockfile -l1024 -ml


  cat $ORGMAIL >>.newmail &&


   cat /dev/null >$ORGMAIL


  lockfile -mu


  formail -s procmail <.newmail &&


   rm -f .newmail


  rm -f .newmail.lock
fi
exit 0








A sample small $HOME/.procmailrc:


PATH=/usr/local/bin:/usr/bin:/bin
MAILDIR=$HOME/Mail      #you'd better make sure it exists
DEFAULT=$MAILDIR/mbox   #completely optional
LOGFILE=$MAILDIR/from   #recommended
:0:
* ^From.*berg
from_me
:0
* ^Subject:.*Flame
/dev/null


Other examples for rcfile recipes can be looked up in the
    procmailex(5) man page.








SOURCE


This program is part of the procmail
    mail-processing-package (v3.22) available at http://www.procmail.org/ or
    ftp.procmail.org in pub/procmail/.






MAILINGLIST


There exists a mailinglist for questions relating to any program
    in the procmail package:




<procmail-users@procmail.org>







for submitting questions/answers.





<procmail-users-request@procmail.org>



for subscription requests.









  

  If you would like to stay informed about new versions and official patches
    send a subscription request to




procmail-announce-request@procmail.org





(this is a readonly list).





AUTHORS


Stephen R. van den Berg




<srb@cuci.nl>






Philip A. Guenther




<guenther@sendmail.com>











  

    2001/08/27
    BuGless