Manual Pages for UNIX Darwin command on man procmail

PROCMAIL(1) PROCMAIL(1)

NAME

procmail - autonomous mail processor

SYNOPSIS

pprrooccmmaaiill [-ppttooYY] [-ff fromwhom]

[parameter==value | rcfile] ...

pprrooccmmaaiill [-ttooYY] [-ff fromwhom] [-aa argument] ...

-dd recipient ...

pprrooccmmaaiill [-ppttYY] -mm [parameter==value] ... rcfile

[argument] ....br pprrooccmmaaiill -vv

DESCRIPTION

For a quick start, see NNOOTTEESS at the end.

PPrrooccmmaaiill should be invoked automatically over the ..ffoorrwwaarrdd file mecha-

nism as soon as mail arrives. Alternatively, when installed by a sys-

tem administrator, it can be invoked from within the mailer immedi-

ately. When invoked, it first sets some environment variables to

default values, reads the mail message from stdin until an EOF, sepa-

rates the body from the header, and then, if no command line arguments

are present, it starts to look for a file named $$HHOOMMEE//..pprrooccmmaaiillrrcc.

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, proc-

mail will store the mail in the default system mailbox.

If no rcfiles and no -pp have been specified on the command line, proc-

mail will, prior to reading $HOME/.procmailrc, interpret commands from

//eettcc//pprrooccmmaaiillrrcc (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., pro-

visions have been made to enable procmail to be invoked in a special

sendmail rule. The rcfile format is described in detail in the pprrooccmmaaiillrrcc(5) man page.

The weighted scoring technique is described in detail in the pprroocc-

mmaaiillsscc(5) man page. Examples for rcfile recipes can be looked up in the pprrooccmmaaiilleexx(5) man page. SSiiggnnaallss TTEERRMMIINNAATTEE Terminate prematurely and requeue the mail. HHAANNGGUUPP Terminate prematurely and bounce the mail. IINNTTEERRRRUUPPTT Terminate prematurely and bounce the mail. QQUUIITT Terminate prematurely and silently lose the mail. AALLAARRMM Force a timeout (see TTIIMMEEOOUUTT)).. UUSSRR11 Equivalent to a VVEERRBBOOSSEE=off. UUSSRR22 Equivalent to a VVEERRBBOOSSEE=on. OOPPTTIIOONNSS

-vv Procmail will print its version number, display its compile time

configuration and exit.

-pp Preserve any old environment. Normally procmail clears the envi-

ronment 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 prede-

fined environment variables, it will happily overwrite them with its own defaults. For the list of environment variables that

procmail will preset see the pprrooccmmaaiillrrcc(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.

-tt 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.

-ff fromwhom

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).

-oo Instead of allowing anyone to generate `From ' lines, simply over-

ride the fakes.

-YY Assume traditional Berkeley mailbox format, ignore any CCoonntteenntt-

LLeennggtthh:: fields.

-aa argument

This will set $1 to be equal to argument. Each succeeding -aa

argument will set the next number variable ($2, $3, etc). It can

be used to pass meta information along to procmail. This is typi-

cally done by passing along the $@x information from the sendmail

mailer rule.

-dd recipient ...

This turns on explicit delivery mode, delivery will be to the

local user recipient. This, of course, only is possible if proc-

mail 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

-pp.

-mm 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 //eettcc//pprrooccmmaaiillrrccss// 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 sym-

bolic link). For some advanced usage of this option you should look in the EEXXAAMMPPLLEESS section below..SH 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; aannyy ootthheerr

rreellaattiivvee path is relative to $HOME, unless the -mm 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 com-

mand 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 $$HHOOMMEE//..pprrooccmmaaiillrrcc. 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. EEXXAAMMPPLLEESS Examples for rcfile recipes can be looked up in the pprrooccmmaaiilleexx(5) man page. A small sample rcfile can be found in the NNOOTTEESS section below.

Skip the rest of this EXAMPLES section unless you are a system adminis-

trator who is vaguely familiar with sendmail.cf syntax.

The -mm 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 rule-

set 0) to filter mail through the procmail mailer (please note the

leading tab to continue the rule, and the tab to separate the com-

ments):

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

//eettcc//ppaasssswwdd to set the recipient's LOGNAME, HOME and SHELL

variable defaults

/var/mail/$LOGNAME ytm alo; oh h sse mibx n te

immediate directory it is in will be created

every time procmail starts and either one is not

present //eettcc//pprrooccmmaaiillrrcc initial global rcfile //eettcc//pprrooccmmaaiillrrccss// special privileges path for rcfiles

$$HHOOMMEE//..pprrooccmmaaiillrrcc default rcfile

/var/mail/$LOGNAME.lock

lockfile for the system mailbox (not automati-

cally used by procmail, unless $DEFAULT equals

/var/mail/$LOGNAME and procmail is delivering to

$DEFAULT)

//uussrr//ssbbiinn//sseennddmmaaiill default mail forwarder

????????``hhoossttnnaammee`` temporary `unique' zero-length files created by

procmail

procmail terminates with EXNOUSER assuming that

this mailbox must not be delivered to. Bad substitution of "x" Not a valid environment variable name specified. Closing brace unexpected

There was no corresponding opening brace (nest-

ing block). Conflicting options Not all option combinations are useful Conflicting x suppressed Flag x is not compatible with some other flag on this recipe. Couldn't create "x" The system mailbox was missing and could not/will not be created. Couldn't create maildir part "x" The maildir folder "x" is missing one or more

required subdirectories and procmail could not

create them. Couldn't create or rename temp file "x"

An error occurred in the mechanics of deliver-

ing to the directory folder "x". Couldn't determine implicit lockfile from "x"

There were no `>>' redirectors to be found, us-

ing simply `$LOCKEXT' as locallockfile.

Couldn't read "x" 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. Couldn't unlock "x" Lockfile was already gone, or write permission to the directory where the lockfile is has been denied. Deadlock attempted on "x" The locallockfile specified on this recipe is

equal to a still active $LOCKFILE.

Denying special privileges for "x" Procmail will not take on the identity that

comes with the rcfile because a security viola-

tion was found (e.g. -pp or variable assignments

on the command line) or procmail had insuffi-

cient privileges to do so. Descriptor "x" was not open

As procmail was started, stdin, stdout or stderr

was not connected (possibly an attempt to sub-

vert security) Enforcing stricter permissions on "x" The system mailbox of the recipient was found to

be unsecured, procmail secured it.

Error while writing to "x" Nonexistent subdirectory, no write permission, pipe died or disk full. Exceeded LINEBUF Buffer overflow detected, LINEBUF was too small, PROCMAILOVERFLOW has been set. MAILDIR is not an absolute path MAILDIR path too long ORGMAIL is not an absolute path ORGMAIL path too long default rcfile is not an absolute path default rcfile path too long The specified item's full path, when expanded, was longer than LINEBUF or didn't start with a file separator. Excessive output quenched from "x" The program or filter "x" tried to produce too much output for the current LINEBUF, the rest was discarded and PROCMAILOVERFLOW has been set. Extraneous x ignored The action line or other flags on this recipe makes flag x meaningless. Failed forking "x" Process table is full (and NORESRETRY has been exhausted). Failed to execute "x" Program not in path, or not executable. Forced unlock denied on "x"

No write permission in the directory where lloocckk-

ffiillee "x" resides, or more than one procmail try-

ing to force a lock at exactly the same time.

Forcing lock on "x" LLoocckkffiillee "x" is going to be removed by force be-

cause of a timeout (see also: LLOOCCKKTTIIMMEEOOUUTT). Incomplete recipe The start of a recipe was found, but it stranded in an EOF. Insufficient privileges Procmail either needs root privileges, or must

have the right (e)uid aanndd (e)gid to run in de-

livery mode. The mail will bounce. Invalid regexp "x" The regular expression "x" contains errors (most likely some missing or extraneous parens).

Kernel-lock failed While trying to use the kernel-supported locking

calls, one of them failed (usually indicates an

OS error), procmail ignores this error and pro-

ceeds.

Kernel-unlock failed See above.

Lock failure on "x" Can only occur if you specify some real weird (and illegal) lockfilenames or if the lloocckkffiillee could not be created because of insufficient permissions or nonexistent subdirectories. Lost "x" 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).

Missing action The current recipe was found to be incomplete. Missing closing brace A nesting block was started, but never finished.

Missing name The -f option needs an extra argument.

Missing argument You specified the -a option but forgot the argu-

ment.

Missing rcfile You specified the -m option, procmail expects

the name of an rcfile as argument.

Missing recipient You specified the -d option or called procmail

under a different name, it expects one or more recipients as arguments. No space left to finish writing "x" The filesystem containing "x" does not have

enough free space to permit delivery of the mes-

sage to the file. Out of memory The system is out of swap space (and NORESRETRY has been exhausted). Processing continued The unrecognised options on the command line are ignored, proceeding as usual. Program failure (nnn) of "x"

Program that was started by procmail returned

nnn instead of EXITSUCCESS (=0); if nnn is neg-

ative, then this is the signal the program died on. Quota exceeded while writing "x" The filesize quota for the recipient on the

filesystem containing "x" does not permit deliv-

ering the message to the file. Renaming bogus "x" into "x" The system mailbox of the recipient was found to

be bogus, procmail performed evasive actions.

Rescue of unfiltered data succeeded/failed

A filter returned unsuccessfully, procmail tried

to get back the original text. Skipped: "x" Couldn't do anything with "x" in the rcfile (syntax error), ignoring it. Suspicious rcfile "x" The owner of the rcfile was not the recipient or

root, the file was world writable, or the direc-

tory that contained it was world writable, or

this was the default rcfile ($HOME/.procmailrc)

and either it was group writable or the directo-

ry that contained it was group writable (the rc-

file was not used). Terminating prematurely whilst waiting for ... Procmail received a signal while it was waiting for ... Timeout, terminating "x" Timeout has occurred on program or filter "x". Timeout, was waiting for "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. Truncated file to former size The file could not be delivered to successfully, so the file was truncated to its former size. Truncating "x" and retrying lock "x" does not seem to be a valid filename or the file is not empty. Unable to treat as directory "x" 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. Unexpected EOL Missing closing quote, or trying to escape EOF.

Unknown user "x" The specified recipient does not have a corre-

sponding uid. EXTENDED DIAGNOSTICS

Extended diagnostics can be turned on and off through setting the VER-

BOSE variable.

[pid] time & date Procmail's pid and a timestamp. Generated when-

ever procmail logs a diagnostic and at least a

second has elapsed since the last timestamp.

Acquiring kernel-lock Procmail now tries to kernel-lock the most re-

cently opened file (descriptor). Assigning "x" Environment variable assignment. Assuming identity of the recipient, VERBOSE=off Dropping all privileges (if any), implicitly turns off extended diagnostics. Bypassed locking "x" The mail spool directory was not accessible to

procmail, it relied solely on kernel locks.

Executing "x" Starting program "x". If it is started by proc-

mail directly (without an intermediate shell),

procmail will show where it separated the argu-

ments by inserting commas.

HOST mismatched "x" This host was called "x", HOST contained some-

thing else. Locking "x" Creating lockfile "x". Linking to "x" Creating a hardlink between directory folders. Match on "x" Condition matched. Matched "x" Assigned "x" to MMAATTCCHH. No match on "x" Condition didn't match, recipe skipped.

Non-zero exitcode (nnn) by "x"

Program that was started by procmail as a condi-

tion or as the action of a recipe with the `W' flag returned nnn instead of EXITSUCCESS (=0); the usage indicates that this is not an entirely unexpected condition.

Notified comsat: "$LOGNAME@offset:file"

Sent comsat/biff a notice that mail arrived for

user $LOGNAME at `offset' in `file'.

Opening "x" Opening file "x" for appending. Rcfile: "x" Rcfile changed to "x".

Reiterating kernel-lock

While attempting several locking methods, one of these failed. Procmail will reiterate until they all succeed in rapid succession. Score: added newtotal "x"

This condition scored `added' points, which re-

sulted in a `newtotal' score. Unlocking "x" Removing lockfile "x" again. WWAARRNNIINNGGSS You should create a shell script that uses lloocckkffiillee(1) before invoking

your mail shell on any mailbox file other than the system mailbox (un-

less of course, your mail shell uses the same lockfiles (local or glob-

al) 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 -tt 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 postmas-

ter and other users. The //eettcc//pprrooccmmaaiillrrcc file might be executed with root privileges, so be very careful of what you put in it. SSHHEELLLL 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: DDRROOPPPPRRIIVVSS.

Keep in mind that if cchhoowwnn(1) is permitted on files in //eettcc//pprrooccmmaaiill-

rrccss//, that they can be chowned to root (or anyone else) by their cur-

rent owners. For maximum security, make sure this directory is exe-

cutable 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 do-

main. 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. Per-

haps 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 be-

fore 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 chil-

dren.

A continued CCoonntteenntt-LLeennggtthh:: 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. MMIISSCCEELLLLAANNEEOOUUSS

If there is an existing CCoonntteenntt-LLeennggtthh:: field in the header of the mail

and the -YY option is not specified, procmail will trim the field to re-

port the correct size. Procmail does not change the fieldwidth.

If there is no CCoonntteenntt-LLeennggtthh:: field or the -YY option has been speci-

fied 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 proc-

mail is running under, have no corresponding /etc/passwd entry, then

HOME will default to /, LOGNAME will default to #uid, SHELL will de-

fault 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-rela-

tive 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/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), proc-

mail will upon startup try to rename it into a file starting with `BO-

GUS.$LOGNAME.' and ending in an inode-sequence-code. If this turns out

to be impossible, OORRGGMMAAIILL will have no initial value, and hence will inhibit delivery without a proper rcfile.

If /var/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 ddoonn''tt need to use lockfiles to prevent several concurrently running

procmail programs from messing up.

Delivering to MH folders is slightly more time consuming than deliver-

ing to normal directories or mailboxes, because procmail has to search

for the next available number (instead of having the filename immedi-

ately available).

On general failure procmail will return EXCANTCREAT, unless option -tt

is specified, in which case it will return EXTEMPFAIL.

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@offsetofmessageinmailbox:absolutepathtomailbox

Whenever procmail itself opens a file to deliver to, it consistently

uses the following kernel locking strategies: ffccnnttll(2) and lloocckkff(3).

Procmail is NFS-resistant and eight-bit clean.

NNOOTTEESS

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 and can

be obtained by sending a mail to mail-server@rtfm.mit.edu with the fol-

lowing 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 in-

voked when your mail arrives. In this case your $HOME/.forward (be-

ware, it hhaass 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.The \fB#\fP\fIYOURUSERNAME\fP is not actually a

parameter that is required by procmail, in fact, it will be discarded

by sh before procmail ever sees it; it is however a necessary kludge

against overoptimising sendmail programs:

"|IFS=' '&&p=/usr/bin/procmail&&test -f $p&&exec $p -Yf-||exit 75 ##YOURUSERNAME"

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 periodi-

cally be called from within ccrroonn(1), or whenever you start reading mail):

#!/bin/sh

ORGMAIL=/var/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

AA ssaammppllee ssmmaallll $$HHOOMMEE//..pprrooccmmaaiillrrcc::

PATH=/bin:/usr/bin:/usr/bin

MAILDIR=$HOME/Mail #you'd better make sure it exists

DEFAULT=$MAILDIR/mbox #completely optional

LOGFILE=$MAILDIR/from #recommended

:0: * ^From.*berg fromme :0 * ^Subject:.*Flame /dev/null Other examples for rcfile recipes can be looked up in the pprrooccmmaaiilleexx(5) man page. SSOOUURRCCEE

This program is part of the procmail mail-processing-package (v3.22)

available at http://www.procmail.org/ or ftp.procmail.org in ppuubb//pprroocc-

mmaaiill//. MMAAIILLIINNGGLLIISSTT There exists a mailinglist for questions relating to any program in the

procmail package:

for submitting questions/answers.

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 Philip A. Guenther BuGless 2003/10/14 PROCMAIL(1)