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Table of contents
1.0 Document id
1.1 General
1.2 What is Procmail?
1.3 Abbreviations and thanks
1.4 Version information
1.5 Document layout and maintenance
1.6 About presented recipes
1.7 Variables used in recipes
1.8 About "useless use of cat award"
2.0 UBE in Internet
2.1 Terms used and foreword
2.2 UBE strategies
2.3 UBE and bouncing message back
2.4 UBE and "I don't mind" attitude
2.5 We need a law against UBE
3.0 Anti-UBE pointers
3.1 NoCEM, CAUCE and others
3.2 General Filtering pages (more than procmail)
3.3 Junk email and spam
3.4 Comprehensive list of spammers
3.5 Misc pointers
3.6 Questionable UBE stop services
3.7 UBE related newsgroups or mailing lists
3.8 Software: adcomplain -- Perl junk email rport
3.9 Software: Ricochet -- Perl junk email rport
3.10 Software: yell -- perl
3.11 Software: RBL lookup tool -- C
3.12 Software: mapSoN
3.13 Software: spamgard
3.14 Software: Spam Be Gone
3.15 Software: ifile - Perl
3.16 Software: ClearMail
4.0 Procmail pointers
4.1 Where to get procmail binary
4.2 Where is procmail developed
4.3 About procmail's Y2K compliance
4.4 Procmail mailing lists
4.5 Procmail recipe modules and faqs
4.6 Procmail mode for Emacs
4.7 Procmail module list
4.8 Where to get Procmail code and modules
4.9 Procmail code to filter UBE
5.0 Dry run testing
5.1 What is dry run testing
5.2 Why the From field is not okay after dry run
5.3 Getting default value of a procmail variable
6.0 Things to remember
6.1 Get the newest procmail
6.2 Csh's tilde is not supported
6.3 Be sure to write the recipe start right
6.4 Always set SHELL
6.5 Check and set PATH
6.6 Keep the log on all the time
6.7 Never add a trailing slash for directories
6.8 Remember what term DELIVERED means
6.9 Beware putting comment in wrong place
6.10 Brace placement
6.11 Local lockfile usage
6.12 Global lockfile
6.13 Gee, where do I put all those ! * $ ??
6.14 Sending automatic reply, use X-loop header
6.15 Avoid extra shell layer (check command for SHELLMETAS)
6.16 Think what shell commands you use
6.17 Using absolute path when calling a shell program
6.18 Disabling recipe temporarily
6.19 Keep message backup, no matter what
6.20 Order of the procmail recipes
7.0 Procmail flags
7.1 The order of the flags
7.2 Flag w and recipe with |
7.3 Flag w, lockfile and recipe with |
7.4 Flag f and w together
7.5 Flags h and b
7.6 Flag h and sinking to /dev/null
7.7 Flag i and pipe flag f
7.8 Flag r
7.9 Flag c's background
7.10 Flag c before nested block forks a child
7.11 Flag c and understanding possible forking penalty
7.12 Flags before nested block
7.13 Flags aAeE tutorial
8.0 Matching and regexps
8.1 Philosophy of abstraction in regexps
8.2 Matches are not case sensitive
8.3 Procmail uses multiline matches
8.4 Headers are folded before matching
8.5 Improving Space-Tab syndrome
8.6 Handling exclamation character
8.7 Rules for generating a character class
8.8 Matching space at the end of condition
8.9 Beware leading backslash
8.10 Correct use of TO Macro
8.11 Procmail's regexp engine
8.12 Procmail and egrep differences
8.13 Undesrtanding procmail's minimal matching (stingy vs. greedy)
8.14 Explaining \/ and ()\/
8.15 Explaning ^^ and ^
8.16 ANDing traditionally
8.17 ORing traditionally
8.18 ORing and score recipe
8.19 ORing by using De Morgan rules
9.0 Variables
9.1 Setting and unsetting variables
9.2 Variable initialisation and sh syntax
9.3 Testing variables
9.4 What does $\VAR mean?
9.5 Common pitfalls when using variables
9.6 Quoting: Using single or double quotes
9.7 Quoting: Passing values to an external program
9.8 Passing values from an external program
9.9 Incrementing a variable by a value N
9.10 Comparing values
9.11 Strings: How many characters are there in a given string?
9.12 Strings: How to strip trailing newline.
9.13 Strings: deriving the last N characters of a string.
9.14 Strings: Getting partial matches from a string.
9.15 Strings: Procmail string manipulation example
9.16 How to raise a flag if the message was filed
9.17 Dollar sign in condition lines.
9.18 Finding mysterious foo variable
9.19 Storing code to variable
9.20 Getting headers into a variable.
9.21 Converting value to lowercase
10.0 Suggestions and miscellaneous
10.1 Speeding up procmail
10.2 See the procmail installation's examples
10.3 Printing statistics of your incoming mail
10.4 Storing UBE mailboxes outside of quota
10.5 Using first 5-30 lines from the message
10.6 Using cat or echo in scripts?
10.7 How to run an extra shell command as a side effect?
10.8 Forcing "ok" return status from shell script
10.9 Make your own .procmailrc available to others
10.10 Using dates efficiently
10.11 Keep simple header log
10.12 Gzipping messages
10.13 Emergency stop for your .procmailrc
11.0 Scoring
11.1 Using scores by an example
11.2 Brief Score tutorial
11.3 Score's scope
11.4 Counting length of a string
11.5 Counting lines in a message (Adding Lines: header)
11.6 Determining if body is longer than header
11.7 Matching last Received header
11.8 How to add Content-Length header
11.9 Testing message size or number of lines
11.10 Counting commas with recursive includerc
12.0 Formail usage
12.1 Fetching fields with formail -x
12.2 Always use formail's -rt switch
12.3 Using -rt and rewriting the From address
12.4 Formail -rt and Resent-From header
12.5 Quoting the message
12.6 Without quoting the message
12.7 How to include headers and body to the reply message
12.8 Adding text to the beginning of message
12.9 Adding text to the end of message
12.10 How to truncate headers (save filing space)
12.11 Adding extra headers from file
12.12 Splitting digest
12.13 Mailbox: Splitting to individual files
12.14 Mailbox: Extracting all From addresses from mailbox
12.15 Mailbox: Applying procmail recipe on whole mailbox
12.16 Mailbox: run series of commands for each mail (split mailbox)
12.17 Option -D and cache
12.18 Option -D and message-id in the body
12.19 Reducing formail calls (conditionally adding fields)
12.20 Formail -A -a options
12.21 Formail -e -s options
13.0 Saving mailing list messages
13.1 Using subroutine pm-jalist.rc to detect mailing lists
13.2 Using plus addressing foo+bar@address.com
13.3 Using RFC comment trick for additional information
13.4 Simple mailing list handling
13.5 Archiving according to TO
13.6 Using Return-Path to detect mailing lists
14.0 Procmail, MIME and HTML
14.1 Mime Bibliography
14.2 Mime notes
14.3 Software to deal with mime or html
14.4 Mime content type application/ms-tnef
14.5 Trapping html mime messages
14.6 Complaining about html messages
14.7 Converting HTML body to plain text
14.8 Getting rid of unwanted mime attachments (html, vcard)
14.9 Sending contents of a html page in plain text to someone
15.0 Simple recipe examples
15.1 Saving: MH folders -- numbered messages
15.2 Saving: to monthly folders
15.3 Modifying: Filtering basics
15.4 Modifying: Squeezing empty lines around message body
15.5 Modifying: shuffling headers always to same order
15.6 Service: Auto answerer to empty messages
15.7 Service: File server -- send fileas as attachments upon request
15.8 Service: Ping responder
15.9 Service: simple vacation with procmail
15.10 Service: vacation code example
15.11 Service: Auto-forwarding
15.12 Service: forward only specific messages
15.13 Service: Making digests
15.14 Kill: killing advertisement headers and footers
15.15 Kill: simple killfile recipe with procmail
15.16 Kill: duplicate messages
15.17 Kill: spam filter with simple recipes
15.18 Kill: (un)subscribe messages
15.19 Time: Once a day cron-like job
15.20 Time: Running a recipe at a given time
15.21 Time: Triggering email and using cron
15.22 Decoding: Uudecode
15.23 Decoding: MIME
15.24 How to send commands in the message's body
15.25 Matching two words on a line, but not one
15.26 How to define personal XX macros?
15.27 How to change subject by body match
15.28 How to change Subject according to some other header
15.29 How to call program with parameters
16.0 Miscellaneous recipes
16.1 Matching valid Message-Id header
16.2 Sending two files in a message
16.3 Excessive quoting of message
16.4 Sending message to pager in chunks
16.5 Playing particular sound when message arrives
16.6 Combining multiple Original-Cc and Original-To headers
16.7 Forwarding sensitive messages in encrypted format
17.0 Procmail and PGP
17.1 Decrypt pgp messages automatically
17.2 Getkeys from keyserver
17.3 Auto grab incoming pgp keys
18.0 Includerc usage
18.1 Using: multiple rc files
18.2 Using: You can call rc file conditionally
18.3 Autoloading an rc file
18.4 Making: naming of the rc file
18.5 Making: Using namespace when saving procmail variables
18.6 Making: Public and private variables in rc file
18.7 The rules of thumb for constructing general purpose rc file
18.8 An includerc skeleton
19.0 Mailing list server
19.1 Mailing list server pointers
19.2 Simple Mailing list server
20.0 Common troubles
20.1 Procmail modes: normal, delivery, and mailfilter.
20.2 Procmail as sendmail Mlocal mail filtering device
20.3 Procmail doesn't pass 8bit characters
20.4 My ISP isn't very interested in installing procmail
20.5 My ISP has systemwide procmailrc; is this a good idea?
20.6 Procmail changes mailbox and directory permissions
20.7 Changing mbox permission during compilation to 660
20.8 The .forward file must be real file
20.9 Using .forward if procmail already is LDA
20.10 Mail should be put in the mailqueue if write fails
20.11 Qmail: how to make it work with procmail
20.12 Qmail: Procmail looks file from /var/spool/mail only
20.13 Qmail: patch to procmail 3.11pre7 to work with Maildirs
20.14 AFS: How to use Procmail when HOME is in AFS cell
20.15 Help, some idiot sent my address to 30 mailing lists
20.16 Help, Procmail beeps and prints to my console
20.17 Help, procmail dumps mail to console
20.18 Help, corrupted From_ line in mailbox
20.19 Directing user's mail to HOME instead of /var/spool/
20.20 NFS mounting /var/mail is a good way to get bad performance
20.21 I can't see the sendmail's response in LOGFILE
20.22 Compiling procmail and choosing locking scheme
20.23 Forwarding lot of mail causes heavy load
20.24 What happens to mail if MDA Procmail fails
20.25 Procmail reads entire 90Mb message into memory
20.26 Help, procmail uses occasionally huge chunk of memory
20.27 Procmail signalled out of memory in my verbose log
20.28 Variables DEFAULT and ORGMAIL
20.29 When DEFAULT cannot be mailed to
20.30 Variable DROPPRIVS
20.31 Variable HOME
20.32 Variable HOST
20.33 Variable LINEBUF
20.34 Variable LOG and LOGFILE
20.35 Variable TRAP
20.36 Variable UMASK
20.37 UMSAK and permissions
20.38 Performance difference between backtick and "|" recipe
20.39 Procmail's temporary file names while writing file out
20.40 Parameter $@
20.41 Procmail variables are null terminated (detecting null string)
20.42 FROM_DAEMON TO and TO_ and case-sensitiveness
20.43 TO_ macro deciphered
20.44 TO_ macro and RFC 822
20.45 FROM_DAEMON deciphered
21.0 Technical matters
21.1 List of exit codes
21.2 List of precedence codes
21.3 Sendmail and -t
21.4 RFC822 Reply-To and formail problem with multiple recipients
21.5 Procmail and IMAP server
21.6 Machine which processes mail
21.7 Compiling procmail and MAILSPOOLHOME
22.0 Smartlist
22.1 MLM RFC
22.2 Other mailing list software
22.3 SmartList code (mailing list implementation with procmail)
22.4 Installation trouble: getparams
22.5 Accepting mail only from users in whitelist(s)
23.0 Additional procmail or MUA software
23.1 Comstat to handle multiple mailboxes
23.2 Elm and pgp support (Mutt)
23.3 MH sites
24.0 Additional procmail software for Emacs
24.1 What is Emacs
24.2 Emacs and procmail mode and Lint
24.3 Emacs and lining up backslashes
24.4 Emacs and browsing mailbox files
24.5 Emacs and live-mode.el
24.6 Emacs and font-lock.el
25.0 Procmail, Emacs and Gnus
25.1 Gnus pointers
25.2 Why use procmail with Gnus
25.3 Setting up gnus for procmail - Basics
25.4 Gnus for procmail - More gnus
25.5 Emacs and Gnus -- Fiddling with spool files
25.6 Gnus and article snippets
25.7 Emacs GNUS - POP - Procmail
26.0 RFC, Request for comments
26.1 RFCs and their jurisdiction (munged Addresses)
26.2 Comments about addresses munging
26.3 RFC and valid email address characters
26.4 RFC and login-name@fdqn
26.5 RFCs and message's signature
26.6 RFC and using MIME in usenet newsgroups
26.7 Some RFC Pointers
27.0 Introduction to E-mail Headers
27.1 To find out more about email (Resources)
27.2 Lecture by Alan Stebbens
27.3 Applied to received messages
27.4 Bcc lecture by Alan Stebbens
27.5 Bcc lecture by Philip Guenther
28.0 Message's headers
28.1 What is correct From address syntax
28.2 What's that X-UIDL header?
28.3 What is that first From_ header?
28.4 Message-Id header
28.5 Received header
28.6 Return-Path
28.7 Errors-To
28.8 X-Subscription-Info
28.9 Reply-To header
28.10 Mail-Copies-To header
28.11 Mail-Followup-To and Reply-To-Personal headers
28.12 Content-Length header and From_ specification
28.13 Moral about CC copies in usenet
29.0 Other interesting code
29.1 Misc email related pointers
29.2 Expire mail pointers
29.3 Usenet News related pointers
29.4 Code: Perl Extract procmail man pages from 3.11pre7.tar.gz
29.5 Code: Sh remove matching lines from file
1.0 Document id
1.1 General
.@(#) $Id: pm-tips.txt,v 1.76 1999/11/10 13:55:12 Jari Aalto Exp $
.$Keywords: procmail sendmail formail mail UBE UCE spam filter $
.$URL: http://www.procmail.org/jari/ $
.$Contactid: $
.$FileServer: send mail to Contactid with subject "send help" $
.$UrlLinksLastChecked: 1999-04-30 $
.@(#) This is a procmail tips page: a collection of procmail recipes,
.@(#) instructions, howtos. The document also contains URL pointers to
.@(#) the procmail mailing list and sites that fight against Internet
.@(#) UBE. You will also find many other interesting subjects that
.@(#) discuss about internet email: headers, mime and RFCs. There is
.@(#) also lot of room dedicated to Emacs and Gnus, simply because
.@(#) those are the best tools you find from Unix to deal with your
.@(#) mail and news reading. And I happen to know Emacs quite well.
.@(#) The tips are compiled from the procmail discussion list,
.@(#) from comp.mail.misc and from the author's own experiences with
.@(#) procmail.
This document does not intend to teach you the basics of procmail;
instead you have to be familiar with the procmail man pages
already. You may want to read *Nancy's* and *Era's* procmail faq
pages before this page. Especially Era's link page contains an
excellent collection of useful procmail links and pointers to unix
programs that deal with email (eg. Perl *MHonArc* Email hyperarchiver
at http://www.oac.uci.edu/indiv/ehood/mhonarc.html). If you find
errors or things to improve in this document, please go ahead and
send mail to [jari].
Author's homepage is behind these redirections links. Please keep these
in your bookmark list, not the absolute addresses, because the sutes may
move. These link should point always to the correct location:
http://poboxes.com/jari.aalto/ eg. homepage.html
http://home.eu.org/~jari/
If you want to have automatic notification whenever this page changes,
please visit the link below. To get nicely formatted netmind messages,
see procmail module `pm-janetmind.rc'.
http://minder.netmind.com/
If a mentioned URL is not alive, you may still be able to
successfully find it using the ftp search located at
http://ftpsearch.ntnu.no/
1.2 What is Procmail?
[faq] Procmail is a mail processing utility, which can help you
filter your mail, sort incoming mail according to sender, Subject
line, length of message, keywords in the message, etc, implement an
ftp-by-mail server, and much more. Procmail is also a complete
drop-in replacement for your MDA. (If this doesn't mean anything to
you, you may not want to know.)
Procmail runs under Unix. See Infinite Ink's Mail Filtering and
Robots page for information about related utilities for various other
platforms, and competing Unix programs, too (there aren't that many
of either).
1.3 Abbreviations and thanks
People and documents, abbreviations referred to, tokens used,
are in no particular order.
[stephen] Stephen R. van den Berg, Author of Procmail Last heard
from stephen 1997-08 in procmail mailing list by using address
. Later 1998 due to his regular work activities and
lack of time he nominated Philip Guenther to the head of Procmail
development.
.[aaron] Aaron Schrab
.[alan] Alan K. Stebbens
.[dan] Daniel Smith
.[david] David W. Tamkin
.[ed] Edward J. Sabol
.[elijah] Eli the Bearded
.[hal] Hal Wine
.[jari] Jari Aalto
.[philip] Philip Guenther
.[richard] Richard Kabel
.[sean] Sean B. Straw
.[timothy] Timothy J Luoma
.[walter] Walter Dnes
.[faq] Procmail FAQ j1era+pr@iki.fi
.[manual] Quote from some procmail manual page
o PM-L, Procmail mailing list
o FAQ-L, Faq Maintainers mailing list
http://www.landfield.com/faq-maintainers/faq-server/
http://lists.consensus.com/scripts/lyris.pl?visit=faq-maintainers
http://www.qucis.queensu.ca/FAQs/FAQaid/
o DING-L, Emacs Gnus mail/newsreader mailing list (ding).
http://www.gnus.org/
o <> Text has been rephrased or something was added which
does not exist in original message.
I also thank following people
o Era Eriksson proof read the v1.12 and sent corrections.
o Karl E. Vogel
sent numerous new anti-spam links to be added to the document.
o John Gianni send some nice recipes: one is now
in the procmail module list and the other ideas I have added to
this tips file.
o Tim Potter had a spare moment with v1.27 and
sent lot of spelling corrections. Thank you.
o took 1.48 and sent a huge
55k patch to correct many English language typos. Thank you
very much Guido.
o 1998-10-28 Richard Kabel sent massive patch
to correct language and provided excellent improvement comments.
o 1999-01-08 Steven Alexander thought that
a small perl script would help me to fix spelling mistakes more
easily. The script has been much better correction program that
simple patches. Thank you.
o 1999-06-16 Mark Seiden Did a enermous work to
proofread the v1.74. He sent a massive 105k with many editorial
corrections. My wholeheart thanks to you Mark.
1.4 Version information
Here is version and file size log of the text file, which gives you
some estimate how often you should update your copy.
v1.01 1997-09-13 46 (k)
v1.05 1997-09-14 53
v1.5 1997-09-16 76
v1.6 1997-09-18 94
v1.8 1997-10-01 127
v1.9 1997-10-11 142
v1.10 1997-10-13 181 archive file 1995-10's tips included
v1.13 1997-11-08 218 Era's correction suggestions.
v1.14 1997-11-25 260
v1.17 1997-12-09 343 up till archive 1996-07 now included
v1.24 1997-12-30 415 up till 1996-12 is now included
v1.29 1998-01-30 429 "regexp" section rewrite.
v1.31 1998-03-10 469 Better ordering: ORing rules discussed
v1.32 1998-03-23 471 All recipes checked (by eye)
v1.34 1998-04-02 488 ORing and supreme scoring added
v1.36 1998-04-03 493 Includerc rewritten, plus addressing
v1.41 1998-06-17 510 How to disable recipe quickly with
v1.44 1998-06-19 516 Detecting mailing lists with pm-jalist.rc
v1.45 1998-06-23 521 All recipes checked by eye. Many fixes.
v1.46 1998-06-24 526 Added live urls to procmail archive
v1.49 1998-08-10 529 Guido.Van.Hoeck's 55k patch applied
v1.51 1998-08-18 541 Small changes. MIME notes
v1.52 1998-08-24 553 Flag c forking study, procmail wish list
v1.53 1998-08-24 554 Procmail doesn't pass 8bit characters
v1.55 1998-08-29 565 Fetching fields with formail -x
v1.57 1998-10-06 575 PLUS addr. Convert HTML body to text
v1.58 1998-10-12 583 SmartList and other MLM software discussed
v1.60 1998-10-21 591 UMASK, .forward if procmail already is LDA
v1.63 1998-10-30 595 Richard's english correction patch
v1.64 1998-11-26 602 More Richard's comments integrated
v1.66 1998-12-14 578 Philip took care of bugs/patches listing
v1.67 1998-01-07 579 Eli's procmail recipes in module section
v1.68 1998-01-29 587 Added "Lua" language pointer
v1.69 1999-02-23 590 RFC and using MIME in usenet postings
v1.70 1999-02-26 592 procmail's Y2K compliance
v1.71 1999-03-29 597 Ricochet -- Perl script to fight UBE
v1.72 1999-04-21 597 Links corrected
v1.74 1999-04-26 599 document moved to www.procmail.org
v2.0 1999-10-01 602k Mark Seiden's patch applied. Now under CVS.
1.5 Document layout and maintenance
This document is maintained in plain text format with Emacs and my
text formatting package *tinytf.el* (automatic TOC and indentation
control). Funny marks or indentation are in the text
version so that the Perl text-to-html
filter `t2html.pl' can be used. See more about this at:
http://poboxes.com/jari.aalto/t2html.html
Text version of this file was converted into HTML with command:
% perl5.004_04 t2html.pl \
--html-frame \
--title "Procmail tips page" \
--author "Jari Aalto" \
--email jari.aalto@poboxes.com \
--meta-keywords "procmail, sendmail, mail, filter, faq, ube" \
--meta-description "Procmail tips page" \
--base http://www.procmail.org/jari \
--document http://www.procmail.org/jari \
--url http://www.procmail.org/jari \
--html-body LANG=en \
--Out \
pm-tips.txt
Please also familiarise yourself with unix what(1) and GNU RCS
ident(1), if you have those commands in your system. It is
important that you mark interesting text to these tools so that
someone can get an overview of your supplied files
% what FILES - Print @( # ) tags
% ident FILES - Print $ $ keywords
Sending improvements
Because I'm not English speaking, I regret the bad language I may have
used in this document. If you have any time, 5-10 minutes to find some
spelling mistake or misuse of the English verbs, please go ahead and
send me a patch to correct the wording. The preferred way to send
corrections to this document is as diff(1) output. Here's how to make
corrections send them to me:
The diff option -u is only available in GNU diff, please try to
send the -u diff if possible. If you don't have -u option, use -c
switch.
% cp pm-tips.txt pm-tips.txt.orig
... load the pm-tips.txt to your text editor
... edit the file and save
... Print the version number first
% what pm-tips.txt > pm-tips.txt.diff # see man what(1)
% diff -u -bw pm-tips.txt.orig pm-tips.txt >> pm-tips.txt.diff
...Send content of pm-tips.txt.diff to document maintainer.
1.6 About presented recipes
The recipes presented here are collected from the net and procmail
archives. I have tried my best to keep the recipes as original as
possible, but I have generalised the examples when necessary. If
some recipe doesn't work as announced, please a) send note to
[jari] b) send email to procmail mailing list and ask how to
correct it. I will watch the procmail list and I'll replace any
faulty recipe with correct one.
Sometimes I have taken the liberty to use a simple dot(.) in
regular expressions, where the right, pedantic way would have
been to use an escaped dot. If you want to be very strict, you
should use the escaped dot where applicable.
[free hand version] [pedantic version]
:0 :0
* match.this.site * match\.this\.site
Procmail also accepts assignments without quotes, like this:
var = value
num = 1
dir = /var/mail
But I have adopted a style, where literal strings are assigned with
double quotes:
var = "value"
because the procmail code checker then won't warn you about missing
dollar-sign, which you might have very well forgotten. Emacs fon-lock,
a syntax highlighting package also displays double quoted string
in color.
# If you do this...
var = value
# then it is in fact not clear what was intended:
var = "value" # Did you mean: literal assignment?
var = $value # Did you mean: variable assignment?
Recipe flags are also _not_ stuck together, because for me the
visual distinction of `:0' and `flags' is a valuable one.
[Erm, all stuck] [I like this better]
:0ABDc: :0 A BDc:
1.7 Variables used in recipes
These are part of the procmail module *pm-javar.rc* and are used in
recipes.
# Pure newline; typical usage: LOG = "$NL message $NL"
NL = "
"
Refer to "improving Space-Tab syndrome" section for more details
WSPC = " " # whitespace: space + tab
SPC = "[$WSPC]" # Regexp: space + tab
SPCL = "($SPC|$)" # whitespace + linefeed: spc/tab/nl
NSPC = "[^$WSPC]" # negation
s = $SPC # shortname: like perl -- \s
d = "[0-9]" # A digit -- Perl \d
w = "[0-9a-z_A-Z]" # A word -- Perl \w
W = "[^0-9a-z_A-Z]" # A word -- Perl \W
a = "[a-zA-Z]" # A word, only alphabetic chars
Writing recipes is now a little easier and may look more clear.
*$ Header:$s+$d+$s+$d # Matches "Header: 11 12"
_SUPREME_ = 9876543210, is the highest score value that causes
procmail to bail out. [david] Actually the maximum is 2147483647,
but 9876543210 is easier to remember/type and will function just as
well.
_PMSRC_ = Procmail includerc code directory, where *rc files
reside. Anywhere you want it to be: usually $HOME/pm or
$HOME/.procmail. Here you keep the procmail files, logfiles and
includerc scripts. You can also use the synonym _PMDIR_.
_SPOOL_ = Directory where your procmail delivers the categorized
messages. Like mailing lists:
list.procmail, list.lyx-users, list.emacs, list.elm
and work mail:
work.announcements, work.lab, work.doc, work.customer
and your private message:
mail.usenet, mail.private, mail.default, mail.perl
and unimportant messages
junk.daemon, junk.cron, junk.ube
If you read the procmail-delivered files directly, this directory
is usually $HOME/Mail or $HOME/mail. If you use some other software
that reads these files as mail spool files (like Emacs Gnus), then
this directory is typically ~/Mail/spool/ or similar.
_MY_XLOOP_ = Used to prevent resending messages that have already
been handled. Typically `$LOGNAME@$HOST', but this can be any user
chosen string. Make it it unique to your address. In this document
the definition is:
MY_XLOOP = "X-Loop: $LOGNAME@$HOST"
_SENDMAIL_ = Program to deliver composed mail. Usually standard
Unix `sendmail', but it must have some switches with it. See man
page for more. We use following definition in scripts:
SENDMAIL = "sendmail -oi -t"
_NICE_ = In a Unix environment you can lower the scheduling priority
wth nice(1). If you are conscious of how many external processes you
launch for each piece of mail it would be nice to lower the
priority of such processes. You may see in this tips file that
external processes are called with `NICE' enabled:
:0 w # same as nice -10 script.pls
| $NICE script.pl
_IS_ functions; eg. IS_EXIST is defined as "test -e" and so on.
The definition of _IS_ functions are system-dependent.
E.g. On Irix the "-e" option is not recognized and
the nearest equivalent is "test -r". All _IS_ functions
are defined in the `pm-javar.rc' module.
1.8 About "useless use of cat award"
Randal Schwartz, a well-known Perl programmer and Perl book writer,
started giving emmy rewards for the "useless use of cat command"
whenever someone wrote examples without token "<". Like this:
% cat file.name.this | wc -l
Instead he insisted that the call should have been written like this,
which saves the pipe. (Never mind that `wc' can read the file
directly; this is an example.)
% wc -l < file.name.this
I stick my opinion in this soup and you're free to disagree. When
you see the shell commands used in this document, they are written
so that they can be read from left to right: The "<" is in my
opinion difficult to understand. As an example, I think that:
% cmd1 < file1 | cmd2 > file2
is less clear than my preferred way of writing such commands:
% cat file1 | cmd1 | cmd2 > file2
And now to the purist side: Is saving one pipe process so important?
Let me see, I use a 2Meg file in this test:
% time sh -c "cat some-file-name-is-here | time wc -l"
0.29u 0.11s 0:00.47 85.1%
% time sh -c "wc -l < some-file-name-is-here"
0.27u 0.05s 0:00.39 82.0%
There is not much difference, and this 2Meg file is not typical at
all. The files typically used are many times smaller. The nitpicking is
therefore pointless. Another reason why I use "left to right
pipe writing": when you recall the command in csh, you can edit the
last command's arguments easily. If you used the "<" token, tapping
keyboard is _much_ more tedious (try changing wc command's option
above). Oh yeah, you can write like this to get the command to the
right, but that's even more obscure.
% < some-file-name-is-here wc -l
Dallman Ross also mentioned that csh users can
replace any word in the previous command by use of caret(^) editing
commands, like this:
% cat some-file-name-is-here | time wc -l
% ^some-file-name-is-here^new-file^
--> cat new-file | time wc -l
Ahem, so there, I got it off my chest...
2.0 UBE in Internet
2.1 Terms used and foreword
[Part of this has been excerpted from the Email Abuse Faq]
._UBE_ = Unsolicited Bulk Email
._UCE_ = (subset of UBE) Unsolicited Commercial Email
_Spam_ = Spam describes a particular kind of Usenet posting (and
canned spiced ham), but is now often used to describe many kinds of
inappropriate activities, including some email-related events. It
is technically incorrect to use "spam" to describe email abuse,
although attempting to correct the practice would amount to tilting
at windmills.
_Spam_ = definition by Erik Beckjord. "Some people decide that Spam
is anything you decide you want to ban if you can't handle the
intellectual load on a list." Remember, not to be confused with
real spam, which is unwanted bulk mail.
People are nowadays seeking a cure which will stop
or handle UBE. That can be easily done with procmail (under your
control) and with sendmail (by your sysadm). In order to select the
right strategy against UBE messages, you should read this section
and then decide how you will be using your procmail to deal with it.
2.2 UBE strategies
[Excerpted from the Email Abuse Faq]
4g. I asked to be "removed" - guess what? I got another U*E
Not surprisingly, many UBE outfits treat a "remove" request as
evidence that the address is "live"; a "remove" request to some
bulk emailers will actually guarantee that they will send more to
you. For many others, the remove procedure does not work, either by
chance or design. At this point perhaps you're starting to get a
feel for the type of people with whom you are dealing.
Also, getting removed doesn't keep you from being added the next
time they mine for addresses, nor will it get you off other copies
of the list that have been sold or traded to others. In summary,
there is no evidence of "remove" requests being an effective way to
stop UBE.
4h. I asked to be "removed" - guess what? The message bounced
Probably the remove procedure was false. Any remove procedure that
tells you to send remove requests to AOL, CompuServe, Prodigy,
Hotmail, or Juno is certainly false. The bulk emailers are an
unpopular lot; they forge headers, inject messages into open SMTP
ports, use temporary accounts, and pull other stunts to avoid the
tirade of complaints that follow every mailing.
2.3 UBE and bouncing message back
Has anyone found that bouncing spam does any good at all?
_Note:_ There are several program packages out there that
can with a high degree of success (but not 100%) trace back a
spam even if some headers are faked. This will not help you against
spam houses (which don't care) but will speed you telling
the sysadmins of an open relay. Such tools need human interaction for
proper working. See pointers to them in this document later.
Examine the messages by hand first and feed them to automatic
complain script. See pointers in this document later.
[sean] I had a whole policy message written up that would be sent
out to spammers. Nothing but a waste of my resources. Most return
paths are either completely bogus, or end up bouncing pretty damn
soon after the spam, which just brings you more junk to deal with.
Instead, I choose to send messages occasionally to administrators
and upline providers of domains which spew. "Agreement by action"
is one of the legal standards I like to use (for "should you
continue to send mail to me, that constitutes acceptance of the
terms herein").
InterNIC recently 1997-07 removed the root files for .com, .org,
and .net (I think) from access at their ftp server. Too many
spammers were using them for the purpose of generating mailing
lists. Access to the files now requires an assigned FTP account
from InterNIC. When I get a domain-style spam, I immediately do a
whois to get DNS info on the domain, then grep the root files to
obtain a list of domains serviced by the same DNS. If they appear
spammy (as spam domains tend to), I add these to a list of domains
to filter (egrep) in my primary domain-based ruleset. Works for
me, though the list is getting big.
[Kimmo Jaskari ] Another good reason is
that all those bounces, which get ignored by the spammer/recipient
anyway, still take up needless bandwith on the net. The spam is bad
enough for that, bouncing it back with some more stuff added is just
plain silly. You become part of the problem rather than the solution.
If the bounce even gets to the spammer, the spammer drops it on the
floor unseen.
[1998-11-03 PM-L Mark Shaw ] Jari:
"Autoresponder is bad idea. You need more better heuristics than
what procmail can do. The UBE messages really need human
inspection before you send them out, otherwise you may have to
apologise from lot of people eg if the complaint was mistakenly
sent off to some mailing list or wrong address." Mark: Having
originally set up my anti-spam recipes to be autoresponders, I
absolutely agree with this. I recall one morning when my strongly-
worded no-spam message went out to *everyone* who sent me email for
several hours..... *** shudder ***
2.4 UBE and "I don't mind" attitude
...whenever you see a spam you don't want, hit the delete key and
move on. Grow up and get a life, folks. The spams just don't
bother me. Why the hell does everyone have to go up in arms
everytime someone sends a spam? Spams are harmless! Spams even
sometime are interesting and/or useful!
[Responses from thread in procmail mailing list 1995-10 to
"FREE 1 yr. Magazine" spam.]
[Soren Dayton ]
The simplest reason against UBE is that it is rude. It costs some
people money to get email on some commercial services. This is
fundamentally different than junk snail mail for this reason and
too much spam can prevent people from getting mail (mailboxes can
fill up). So it is both an intrusion into my life _and_ it can
conceivably end in me either loosing money or loosing mail (which is
far more important). It is a burden on the receiver _far_ beyond
just hitting the delete key.
[Mark Seiden ]
people who are able to monitor the incoming machines of one of the
larger online services (like me) can see a sizeable increase in
system load average and volume directly resulting from spams. this
competition for fixed resources inevitably translates to reduced
service for "first class" mail.
It is impossible to engineer a mail system that can cope with an
unlimited amount of abuse. this is in addition to the difficulties
of doing so on a fixed price economic model, and the difficulties
of keeping up with the successful rapid expansion of the population
to be served.
Even if you, an individual, aren't charged anything per piece of
mail, there are costs borne by your service provider per piece of
mail, and these are *somehow* passed on to you. (They've calculated
an average across their entire user population to come up with a
"monthly cost of Internet mail".)
Spamsters and bulk mailers are not at all concerned about
efficiency. as proof of that, many of them are not even courteous
enough to supply a proper return address, so they can prune their
lists of undeliverable mail. all they care about is getting their
message across without their paying anything whatsoever for that
service.
Watch how this will inevitably translate into increased costs for
you, the consumer, unless we change the mechanisms by which bulk
mail is delivered as well as putting an appropriate economic model
in place.
[Steve Simmons ]
If you tolerate spamming, it will only get worse. Spamming has been
stopped again and again. Almost without exception, the spammers
have been tracked down and, via one means or another, have been
convinced to stop spamming.
Spams are harmless? I've already seen the 'Magazine Sub' message
10 or 12 times. I have a low bandwidth line. If I continue to
tolerate spamming, I will pay a very real penalty in performance as
tens, then thousands of spammers do it. Not to mention the
personal time involved in taking care of the crap.
Don't think that the time involved is significant? Just wait. My
wife and I are fairly generous with our time and money. As a
result, we were getting an average of five telephone calls *per
night* asking for money for various causes. A year ago, I adopted
a new policy -- I will not under any circumstances give money to a
caller, and will only consider it upon written solicitation. I
ask them to put me on their `do not call list'. If they do
*anything else* to continue the conversation, I hang up on them.
My wife opposed this, and we agreed to disagree -- if they ask for
her, they get her. If they ask for me, they get my speech. After
a year, she is getting 2-3 calls per night and I'm getting one or
two a week.
My point here is that individual action *does* get re-action from
the mailers. For them, I copy their internet providers on my
complaints and call their Better Business Bureau. It works.
If one does this politely and consistently, 98% of the spammers
will stop. The remaining 2% will discover that they're in a
different world from direct mail or telephone solicitation. Their
mailboxes will be overloaded with complaints (when it takes a
single keystroke to invoke your complain macro, you're very likely
to complain). Then their suppliers mailboxes will be overloaded
with complaints. The free magazine folks, who've been hiding
behind false ids and forging mail, will find that they're on the
wrong side of the law. I'm considering contacting their local
legal officials and urging them to investigate, because it sure
looks like fraud to me (read `Consumer Reports' for a similar case
by surface mail). Should a few more like this come in, I *will*
contact their legal authorities. We have their fax number; it's
all we need to find them.
[Carl Payne ]
Um, I don't know about you or anyone else here, but this cutesy,
"it's-okay-by-me" spam has been circulated under half a dozen
different user names and "domains" on as many mailing lists. It's
obvious to me the sender is trying to make people pissed off--how
can he possibly think someone will buy that crap, and why does he
think it's okay to send 19 and 20K files over a billion groups?
AFAIC, it has to stop. Now. I'm tired of the spam, I'm tired of
the "Who cares" attitude about spam, I'm tired of ISPs letting
people spam, I'm tired of the jetwash of spam, and I'm tired of the
bleedinghearts that say, "Golly, just ignore it, and it'll go
away."
I've got news for you all: when this method of spamming becomes the
preferred method of "marketing" on the internet, and people like us
are the bad guys because we're not allowing such litter to fly
across the fiber, you will care. You will say something, most
probably, "Why didn't we do something about this sooner?"
The guy in the next cube from you, who's paying a per-message
charge through his ISP, is probably going, "Dammit, over three
dollars this month on mail I've itemized as being spam." While
that doesn't seem like a lot, I revert to my earlier statement: if
this becomes the preferred method, his bill (and yours) will go up,
and everyone will wonder why it's too out of control to do anything
about.
Spam has the letters *m-a-s* in it, which en Espanol, means "more."
I say no. Not only no, but hell no. And, I refuse to be told that
my thinking is out of line just because I don't want my mailbox
flooded. Do something now. Do anything now. But, don't be quiet
and listen to anything that sounds like an endorsement of litter
[Wolfgang Weisselberg ]
Worse is that it costs a spammer very little to spam, say, 2
million addresses with 5KB:
o 5 hours unattended time online
o phone costs
o a 'free x hours'-CD or a provider looking the othher way i.e.
something between $0 and $500 (an expensive provider)
It costs all recipients:
o on an average of 5 seconds per UCE to decide that, indeed, it
is one: 115.7 *DAYS* (2777.8 hours) of mailchecking (at $7.5/h
that is just $20833 --- excluding all taxes and so on!)
o 379.5 hours (15.8 days) download time (multiply with your local
phone costs and remember that in most places even in-city calls
cost by the minute)
o the same time as online time (multiply by your provider costs)
o indirect costs (more HDs for the provider (9.5 GB), faster
connections for all the spams, more transmission costs (9.5
GB), faster machines, ...
I can send you the complete calculation if you like :-)
Now, if UCE becomes more common ... how many businesses are
connected to the Internet? Say that every business spamms once
every 10 years, and that they are well distributed over the time.
Number_of_businesses / 3650 = UCE's iniciated per day
UCE's iniciated per day * 2_000_000 (or more)
/ number of email addresses
= UCEs in your mailbox
Guess we are going to need T1's to just get all our mail. And a few
100 secretaries as well. Wave good-bye to usable email.
2.5 We need a law against UBE
Ray Everett-Church , Attorney/Online Consultant
Co-Founder & Congressional Liaison Coalition Against Unsolicited
Commercial Email; article 1997-12 in remailer politics mailing
list
In developing what eventually became the Smith Bill, CAUCE
discussed this rather extensively among our drafting committee. The
bill gives a cause of action against the advertiser, not any of the
pathways taken between you and them. This is consistent with the
interpretation of the fax law (and many other laws for that matter)
wherein the advertiser -- not the advertiser's agent -- is
responsible for the act committed.
As for the single UCE versus bulk issue, the general consensus has
been that while a single piece of spam does not do much damage, it
is fundamentally no less a cost shift than 10 identical messages,
or 100, or 1000, or a million. The only difference is that the
costs being shifted are greater and greater. We discussed many cut
off points... would 50 spams be acceptable? 25? 10? One really well
crafted, hand written, heartfelt and personalized spam be
permissible? And in the end we felt like we were discussion angels
on the heads of pins.
While virtually nobody's system will crash because of one piece of
spam (although George Nemeyer had trouble with three or four pieces
as I recall), what is the ultimate difference if you only get one
piece from each of 15 different advertisers a day? If one spam is
ok, but two are bad, what is the interval... a day, a week?
Enforcement depends on knowing when the threshold is crossed.
So here's a scenario: you receive three spams from what is,
unbeknownst to you, the same person (one advertising weightloss
pills from WeightLoss Associates at PO Box 1, one for an MLM from
MLM Company at PO Box 2, and Bee Pollen from Pollen Partnership at
PO Box 3). Each were individually crafted and appeared to be mailed
only to you.
Under the scenario above, if the law permits one spam, will you
sue?
Would you risk suing one or all of them, gambling that they sent
the spam to anyone other than you (or whatever the threshold is...
10, 25, 50)? Would you risk suing one or all of them on the chance
that they were somehow related? What if there was a chance that
you'd find out that the three companies were really different? What
if you did sue and found that they were owned by the same person,
but were legally organized separate entities and were therefore
each entitled to one spam a piece?
In short... if one spam is permitted, it could make enforcement
incredibly cumbersome, difficult and unlikely, and would present
spammers with many reasons to violate the law knowing the odds of a
suit and successful enforcement are greatly reduced. While bulk
spam is really bad on many levels, whether it's parsed out in very
small volumes makes little or no difference to the ultimate
recipients as far as the diminished utility, cost, and annoyance.
We need a clear, bright line. And the Smith Bill is that.
3.0 Anti-UBE pointers
3.1 NoCEM, CAUCE and others
"NoCEM"
http://www.cm.org/
"Dougal's NoCeM-E"
http://advicom.net/~dougal/antispam/
... Dougal is sysadm for an ISP. His page has wealth of information
about Anti-SPAM Tools. You also find his mailing list for NoCeM-E.
"The Coalition Against Unsolicited Commercial Email (CAUCE)"
http://www.cauce.org/faq.html
...The Problem: Unsolicited commercial email, more commonly known as
"spam", is a growing problem on the Internet. If you've used the
Internet for any length of time, you've probably received
solicitations via email to purchase products or services.
A Solution: A group of Internet users who are fed up with spam have
formed a coalition whose purpose is to amend 47 USC 227, the
section of U.S. law that bans "junk faxing", so that it will cover
electronic mail as well.
"Teergrubing against Spam"
http://www.iks-jena.de/mitarb/lutz/usenet/teergrube.en.html
...`Teergrubing' It's German and means Tar-Pit. Once you have been
stuck you can't get out. ...slow down internet connections in order
to stop UBE abuse. Several hundred teergrubes are able to block
spamming worldwide without blocking any e-mail. How do I start: If
you are the admin of a MX host, install a teergrube.
"Obtuse smtpd for UNIX"
http://www.obtuse.com/smtpd.html
Main (configurable) features:
o deny unauthorized relay (no more relay rape!)
o permit selective relay exceptions (eg. UUCP downstream)
o regex() filtering [block those spamming dialins!]
o deny access for no MX, no PTR, etc.
o defeat % hack
o support MAPS, ORBS, DUL, IMRSS, etc RBLs plus your local RBL
o support exception list for domains for which you will accept mail
o support selective tarpit'ing on refused connections
o individually configurable rejection messages
o precedence and override ordering
o informative log summary scripts
"Lot of good articles about spam"
http://www.sun.com/sunworldonline/swol-12-1997/swol-12-spam.html
"(anti-spam Law) US Representative Chris Smith's statement on junk
e-mail"
http://www.sun.com/sunworldonline/swol-08-1997/swol-08-junkemail.html
...considerable variation in the approaches at the federal level,
and state legislation varies widely as well. Professor David Sorkin
of John Marshall Law School, who summarized and provided links to
the major spam-related lawsuits noted above, also provides status
summaries and links to state and federal legislation
"Select email court cases -- Lots of them"
http://www.jmls.edu/cyber/cases/spam.html
America Online, Inc. v. Cyber Promotions, Inc.,
Compuserve Inc. v. Cyber Promotions, Inc., etc.
"Anti-Spam Directory of Information and Resources"
http://www.ao.net/waytosuccess/nospam.html
"Forum for Responsible and Ethical E-mail (FREE)"
http://www.ybecker.net/
"Ethical Marketing Using FREE Resources"
http://www.ao.net/waytosuccess/index.html
3.2 General Filtering pages (more than procmail)
"Nancy McGough - Mail Filtering FAQ"
http://ssil.uoregon.edu/~trenton/autopage/page7547.html
http://www.ii.com/internet/faqs/launchers/mail/filtering-faq/
"Information Filtering Resources"
http://www.ee.umd.edu/medlab/filter/ Doug Oard
...This page lists all known internet-accessible information
filtering resources.
3.3 Junk email and spam
"Spam FAQ"
ftp://rtfm.mit.edu/pub/usenet/alt.spam/
http://www.cs.ruu.nl/wais/html/na-dir/net-abuse-faq/spam-faq.html
"The email abuse FAQ"
http://members.aol.com/emailfaq/emailfaq.html
What is UBE, UCE, EMP, MMF, MLM, Spam, it is all explained here.
"Get that spammer -- A VERY GOOD LINK"
http://kryten.eng.monash.edu.au/gspam.html
...All about Spam; traceroute, netabuse etc. Full of links and docs
"Whois"
http://www.networksolutions.com/cgi-bin/whois/whois/
"Advertising on Usenet: How To Do It, How Not To Do It"
ftp://rtfm.mit.edu/pub/usenet/advertising/
"Dealing with Junk Email"
http://www.mcs.com/~jcr/junkemaildeal.html
...What you should do (and not do) when you have been victimized by
a junk emailer. This document teaches you how to read headers in
order to trace the origin of junk email, and includes detailed
examples to show you how it is done. Headers are designed for
computers to read, not people, so they can be a little hard to
follow. Therefore, I hereby grant permission to print or
electronically save a copy of this page on your local machine for
your personal use while tracing junk email. Please check back for
updates and corrections, though.
o What Not To Do: Stuff that doesn't work
o What to do: effective techniques, including how to trace junk
email back to its source
o Stay Calm (take a deep breath...)
o Stay Mad (don't get discouraged)
o How to identify the sender and who gives them Internet access
o Who to complain to, abuse addresses, online services
o What to say and how to say it, effective complaining
"How to fight back."
http://www.oeonline.com/~edog/spamstop.html
. Look at the header of the advertising message. Find the
"Message-ID" line. (You might have to tell your e-mail program to
display this.)
. The words after the @ sign are the sender's real--not
faked--Internet Service Provider, or ISP. (Spammers often try to
disguise their address, but the Message-ID is a good clue.)
. Write a complaint to the postmaster of that ISP, similar to the
one below. (If the ISP is junkmail.com, then let
postmaster@junkmail.com hear from you.)
"Practical Tools to Boycott Spam"
http://spam.abuse.net/spam/
...We have been actively engaged in fighting spam for years. Recent
events, including pending court battles, prompt us to present this
page to the public. Fight spam to keep the Internet useful for
everyone.
o Filtering mail to your personal account
o Blocking spam email for an entire site
o Blocking Usenet spam for an entire site
o Blocking IP connectivity from spam sites
o Other tools and techniques for limiting spam
o Sample Acceptable Use Policy statements for ISPs
"Spam -- stop that!"
http://com.primenet.com/spamking/buyerbeware.html
"The Campaign to stop junk email web site"
http://www.mcs.com/~jcr/junkmail.html
...we will attempt to teach victims and potential victims (that's
everyone with an email address) the most effective methods of
prevention and retribution.
"news.admin.net-abuse.* Homepage"
Timothy M. Skirvin
http://www.ews.uiuc.edu/~tskirvin/home/nana/
"The automated spamhandler beta information heap."
http://www.halcyon.com/natew/
"Preventing relaying in Sendmail"
...This package adds two independent features to sendmail,
access control and relay control. They will be described here
simultaneously, but you can elect to include support for only one
of them (either one) on your mail server. Access control lets you
deny access to the server based on the senders envelope address or
his IP address. Relay control lets you decide who gets to relay
email through your server.
ftp://ftp.xyzzy.no/sendmail/access.tar.Z
"Anti-Spam Provisions in Sendmail 8.8"
http://www.sendmail.org/antispam.html
http://maps.vix.com/tsi/
http://www.informatik.uni-kiel.de/%7Eca/email/check.html#check_rcpt
o Preventing relaying through your SMTP port
o Refuse mail from selected hosts
o Restrict mail acceptance from certain users to avoid mailbombing
[1998-06-15 PM-L walter] Somebody's starting to exploit a hole in
sendmail 8.8, where giving a HELO longer than 1024 bytes causes
buffer overflow, and all following "Received:" headers are lost. If
it's done off a relay, we have no clue who sent it. There may be a
more elegant solution, but here's a quick-n-dirty procmail filter
for this stunt...
"Blocking Email"
http://www.nepean.uws.edu.au/users/david/pe/blockmail.html
o Do you or your users, receive "junk email" (aka., "spam")
o Do you have Sendmail R8.8.5 running at your site?
o Would you like to block known "junk email" senders' addresses?
Now you can - and there's no need to patch any source code, either.
Take advantage of Sendmail's check_mail rule, to see if the
sender's address is a member of a nominated "class" - drawn from
the contents of the named file. Additional information and links:
o Prospective Addresses/Domains to Block
o Limiting Unsolicited Commercial Email
o EFF "Net Abuse and Spamming" Archive
o [U.S.] Court Lets AOL Block Email
o Anti-Spam HOWTO
o Net Abuse FAQ
o Figuring out Fake Email & Posts
o Fight Unwanted Email
o Unsolicited Junk Email - Bad for Business
o Fight Unsolicited Email and Mailing
o Yahoo's Junk Email Resources
o jmfilter
o Complaints Addresses at U.S. ISPs
o news.admin.net-abuse.* Homepage
o Processing Mail With ProcMail
o Panix's rc.shared ProcMail Configuration
o ProcMail Workshop
o Email Self Defence
o The SPAM-L mailing list
"US Federal Trade Commission"
http://www.ftc.gov/
...staff publicized the Commission's UCE mailbox, "uce@ftc.gov,"
and invited consumers to forward their UCE to it. spam complaints
"Spam Spade Web based tracking tool"
http://www.blighty.com/
...Figuring out forged headers and verifying IP addresses and
whois information.
"Misc"
http://www.junkbusters.com/
http://www.well.com/~jbremson/spam
http://www.wolfenet.com/~jhardin/procmail-security.html
3.4 Comprehensive list of spammers
"Against Spam -- The garbage collecting."
http://www.spam-archive.org/
To support this archive please forward email spam to
. Everybody is invited to bounce Mail-Spam
he/she has got to this list. This is a mailing list to distribute
actual spam-eMail. All incoming mail will be checked by subject and
from/sender-address wether it has already been distributed or not.
No discussions in this list. To discuss about this list please
subscribe to .
To subscribe to _blacklist-update_ mailing list
TO:
BODY: subscribe blacklist-update you@somewhere.com
Mail to discuss about blacklist if
your name is on it. (maintained by Axel Zinser )
Get the updated blacklist from
ftp://ftp.spam-archive.org/spam/blacklist/
3.5 Misc pointers
Is there a way to block local users from spamming other sites?
Maybe somehow force sentmail to read a rc file that would maybe
then grab the from field and see if the user exists on the system
or not. Or run it through some sort of filters.
[philip] You can and should do this purely in sendmail. I ended up
crafting a check_from ruleset that verifies that the envelope
sender address is either a) not local; b) a local user; or c) a
local alias. At the time I did this mainly to force people to
configure their Eudora clients so they didn't say "Return Address:
yourname@gac.edu" but it also covers the outgoing bogus source
address spam case. For those interested in this kinda thing I've
(just) put it up for FTP:
ftp://ftp.gac.edu/pub/guenther/
"IBM's Secure Mailer -- open source"
http://www.postfix.org/
[1998-12-15 PM-L Matthew McGehrin ] The
official project is known as 'IBM's Secure Mailer'. The
unofficial codename was Vmailer, but they had to rename that, to
Postfix to agree with the lawyers. I should know, I have been
alpha testing this mailer for the past year, and it so blazing
fast, its amazing. It's faster and simplier to use than sendmail,
and also faster and more secure than qmail. It works fine with
procmail. (look in my headers). set
"mailbox_command=/usr/bin/procmail" in /etc/postfix/main.cf
[1998-12-15 PM-L Liviu Daia ] it has
explicit hooks for both procmail and RBL. In fact it's incredibly
easy to setup, I got it compiled and configured (with an actually
usable configuration) in about 15 minutes after downloading it.
Adding masquerading and a virtual domain took another 2 minutes.
:-) You should really give it a try, it's faster than QMail and
_much_ faster than sendmail. So far, I'm quite impressed.
"Qmail"
http://pobox.com/~djb/qmail.html
http://www.qmail.org/
"Sendmail"
http://www.sendmail.org/
"Fetchmail -- old pop3 replacement"
ftp://ftp.ccil.org/pub/esr/
http://www.ccil.org/~esr/
http://www.tuxedo.org/~esr/fetchmail/
"Maildrop filter utility"
http://www.geocities.com/SiliconValley/Peaks/5799/maildrop.README.html
...Alternative to procmail
"Lua"
http://www.tecgraf.puc-rio.br/lua/
[possible replacement for procmail language] ... *Lua* is a
programming language originally designed for extending
applications, but also frequently used as a general-purpose,
stand-alone language. Lua combines simple procedural syntax
(similar to Pascal) with powerful data description constructs based
on associative arrays and extensible semantics. Lua is dynamically
typed, interpreted from bytecodes, and has automatic memory
management with garbage collection, making it ideal for
configuration, scripting, and rapid prototyping.
3.6 Questionable UBE stop services
"IEMMC: Internet E-Mail Marketing Council Formed 1997-03"
The IEMMC was formed to provide an industry wide trade association
for the purpose of promoting responsible e-mail marketing, and to
establish an industry standard code of procedures and ethics which
will internally regulate and govern the commercial e-mail marketing
industry....Under this system, all e-mail of a commercial,
unsolicited nature must pass through a universal filtration system
which will block the sending of any and all commercial e-mail to the
address on the list. Bulk e-mailers will be required to join the
organization
Others have commented that:
...IEMMC is a joke. you are probably not doing yourself any favors
...Don't take that IEMMC seriously! Many people registered with
them and got as many or even more spam as before. After all,
Cyberpromo (the operator of IEMMC) knows that the registered
addresses will be valid for some time, so they can use and sell
this valuable list to other junk mailers.
"Spammer blacklist"
http://www.netchem.com
... Dear Sir/Madam, Your email address may be on
many spammers' lists. We are compiling a *remove* list. Forward the
original junk to
"No Junk E-Mail database"
http://pages.ripco.com:8080/~glr/nojunk.html
...We will help stop unwanted email to you..the list is submitted to
us, and those addresses that appear in the "do not mail" list are
removed and the "cleaned" list is returned
3.7 UBE related newsgroups or mailing lists
alt.kill.spammers
alt.hackers.malicous
alt.2600
[1997-08-13 alt.privacy.anon-server by anonymous poster] Proper
etiquette demands you contact their ISP. However, if the ISP are
not interested in helping you, you should consider a posting in
alt.kill.spammers (or even alt.hackers.malicous or alt.2600) - give
as many details as you can about the spammer.
A certain spam-provider targeted the alt.hackers.malicious
newsgroup. Not the most sensible thing to do. The ISPs IPs were
found, their MX host was hacked. All their DNS entries was
published on alt.2600 (so that everyone could add filters to ignore
all mail from this company). Oh yeah, their password file also made
it to the group! The ISP then posted a complaint to alt.2600, much
to the enjoyment of everyone who took part. That host basically
died a horrible death. I'm pretty sure that not many people are
going to lose any sleep over this! I might as well mention that the
ISP's complaint mentioned that their "freedom" was being
abused. hehehe. Most of these postings can be seen in dejanews
or altavista archives of usenet.
"SPAM-L mailing list and Doug Muth's Page"
http://www.claws-and-paws.com/spam-l/
... "The SPAM-L FAQ" - A FAQ for SPAM-L, an anti-spam mailing list.
This FAQ discusses how to join the list and what to post there, AND
it also delves into the technical aspects of spam. For instance,
the various kinds of forgeries seen in spams are discussed here,
along with information on how to recognise them. If you hate spam,
this is something worth checking out... "TheGoodsites List" - I
maintain this list, which is part of the Spam Boycott, to show
which Internet providers out there act responsibly when dealing
with spam. If you're looking for an ISP and want to know where they
stand on spam, this is the list for you.
Send an email message to
with the words "subscribe SPAM-L " in the
body of the message (no quotes). f you would like to contact the
owner, the convention is the same as with all listserv lists. Just
send e-mail to
3.8 Software: the net abuse page
Scott Hazen Mueller
http://spam.abuse.net/spam/tools/
3.9 Software: adcomplain -- Perl junk email rport
http://www.rdrop.com/users/billmc/adcomplain.html
Adcomplain runs under Unix, Windows-NT, and Windows-95. Adcomplain
is a tool for reporting inappropriate commercial e-mail and usenet
postings, as well as chain letters and "make money fast" postings.
It automatically analyzes the message, composes an abuse report,
and mails the report to the offender's internet service provider.
The report is displayed for your approval prior to mailing.
Adcomplain can be invoked from the command line or automatically
from many news and mail readers.
#todo: url missing
[a user happy user reports] ...About 95% of all cases can be
traced correctly --- unless they come from a known spamhouse;
where complaining to them would not do much good anyway. Mailing
lists with strange Received-Headers also can present problems in
tracing
3.10 Software: Ricochet -- Perl junk email rport
http://www.vipul.net/ricochet/
Vipul Ved Prakash
MailingLi´st: with subject
"subscribe"
A lot of unsolicited email goes unreported because tracing the
origins of a possibly forged mail and finding the right people to
report to is complicated and time-consuming. Ricochet, a smart net
agent, automates this process. It traces the names and add resses
of the systems where the spam originated from along with the
servers that provide domain name resolution services to these
systems (in most cases their ISPs). Then it collects/generates a
list of email addresses of tech/billing/admin/abuse contacts of
these system and mails them a complaint and a copy of the spam.
Detailed description of its workings can be found in the README
file that comes with the package.
3.11 Software: yell -- perl
ftp://ftp.netcom.com/pub/bo/bobmacd/yell (57k)
Bob MacDowell
yell - auto-responds to "spam" e-mail. Scans for site names, e-mail
addresses and Web site names and sends appropriate messages to
users, postmasters and Webmasters.
3.12 Software: ifile - Perl
http://www.cs.cmu.edu/~jr6b/ifile/
Jason Daniel Rennie
...ifile is different from other mail filtering programs in
three major ways: 1) ifile does not require you to generate a set
of rules in order to successfully filter mail 2) ifile uses the
entire content of messages for filtering purposes 3) ifile learns
as you move incorrectly filtered messages to new mailboxes ifile is
not dependent upon any specific mail system and should be adaptable
to any mail system which allows an outside program to perform mail
filtering. Currently, ifile has been adapted to the MH and EXMH
mail systems.
3.13 Software: RBL lookup tool -- C
[1997-12-04 PM-L Edward S. Marshall ]
...rblcheck is a lightweight C program for doing checks against
Paul Vixie's Blackhole List. It works well in conjunction with
Procmail for filtering unwanted bulk email (under QMail, for
example, you can invoke it with the value of the environment
variable TCPREMOTEIP). rblcheck is extremely simple:
% rblcheck 1.2.3.4
where 1.2.3.4 is the IP address you want to check.
This is a quick note to announce the availability of a new tool for
using Paul Vixie's RBL blacklist (see http://maps.vix.com/rbl/ for
more information about the blacklist itself, if you don't already
know). Most tools which use the blacklist block email on a
site-wide basis. For many networks, this treads on both the ideals
of the administration, and on the perceived freedoms of the end
user.
Personally, I don't care either way. :-)
This tool was to fill the need I personally had to reject mail,
since one of the systems I receive mail through cannot, for various
political reasons, implement the available RBL filters on a
site-wide basis.
rblcheck is a simple tool meant to be used from procmail and
other personal filtering systems under UNIX in the absence of a
site-wide filter, as an alternative to imposing site-wide
restrictions, or as a means of imposing restrictions on systems
that cannot support the existing RBL filter patches.
Simply put: you hand it an IP address, and it determines if the IP
is in the RBL filter, providing the caller with a positive or
negative response. With the package, a sample procmail recipe is
provided, and examples of using it under QMail and Sendmail are
given.
.http://maps.vix.com/rbl/
.http://www.isc.org/bind.html The official home page
.http://www.xnet.com/~emarshal/rblcheck/
It has only been tested under Linux 2.x and Solaris 2.5.1. Success
stories, patches, questions, suggestions, and flames can be
directed to me at .
[PM-L Aaron Schrab ] Here is my rbl
setup, but, this depends both upon the format of the Received:
lines, and the way that mail passes through your mail system.
I currently grab the IP address from the first Received: header
inserted by my ISP (I'm a sysadmin at the ISP, so I have a good
knowledge of how mail gets passed around internally). Here's the
recipe that I use.
# if there's a Received: header from one of these servers, it's
# (probably) the right one
BACKUPSERVER = "([yz]\.mx\.execpc\.com)"
VIRTSERVER = "(vm[0-9]+\.mx\.execpc\.com)"
LOCALSERVER = "([abc]\.mx\.execpc\.com)"
# Match a header containing:
# Received: []) by
:0
* $ $SUPREME^0 ^Received:.*\[\/[0-9.]+\]\)$s+by$s+${BACKUPSERVER}
* $ $SUPREME^0 ^Received:.*\[\/[0-9.]+\]\)$s+by$s+${VIRTSERVER}
* $ $SUPREME^0 ^Received:.*\[\/[0-9.]+\]\)$s+by$s+${LOCALSERVER}
{
IP = $MATCH
# trim it down to just the IP address
:0
* IP ?? ^^\/[0-9.]+
{
IP = $MATCH
:0 W
* ! ? /home/aarons/bin/rblcheck -q $IP
{
SPAM = "$SPAM $IP is rbl'd$NL"
}
}
}
It seems to be a procmail issue with letting the IP info
from sendmail pass through to the rblcheck program. I have not
been able to find anyone using rblcheck successfully with
procmail as a delivery agent...
[1998-03-26 PM-L Edward S. Marshall ] This is a
standard problem; you should be able to change the invocation of
procmail the same way as the example (run env, which in turn runs
procmail). Make sure that there is a '-p' argument passed to
procmail; this preserves the environment you're constructing with
env (newer sendmail revisions sanitize the environment for you, so
that's not really an issue).
If you're still having troubles, make sure you're using the latest
incarnation of rblcheck, with the latest supplied procmail recipe;
earlier revisions had rather insidious bugs.
[1998-03-26 PM-L Xavier Beaudouin (kiwi) ] Also it
seems that sendmail 8.9.0Beta3 has builtin rules for
rbl.maps.vix.com. This is somewhat really efficient. I use it with
sendmail 8.8.8 and tcpwrapper every day and there is about 80%
spam rejected. Sounds very good. In your /etc/hosts.allow just add
the following lines :
sendmail: ALL: spawn /usr/local/bin/rblcheck -q %a && \
exec /usr/sbin/sendmail -bs || /bin/echo \\
"469 Connection refused. You are in my Black List !!!\r\b\r\n"
&& \
(safe_finger -l @%h 2>&1 | /bin/mail -s "%d-%h %u" root)
In your /etc/inetd.conf just add this line :
smtp stream tcp nowait root /usr/sbin/tcpd \
/usr/sbin/sendmail -bs
And check that your sendmail is _not_ working as a daemon. That's
all. Also if you have huge queue you can add a /usr/sbin/sendmail -q
in the root crontab... This should help to send some waiting
messages. I think we can use this to wait for official 8.9.0
sendmail since there is some cf/feature/rbl.m4 there.
[timothy] ...I think there's a much more efficient way to do
this: you can compile sendmail -DTCPWRAPPERS and let it run as a
daemon
3.14 Software: mapSoN
Note: You can do exactly the same as below with procmail with one
of the listed procmail modules: pm-jacookie.rc. See the code.
"mapSoN (NoSpam backwards) -- The no spam utility"
http://mapson.gmd.de/
ftp://ftp.gmd.de/gmd/mapson/
Most spam filtering tools I've seen so far are based on procmail, or
a similar tool, and use a list of keywords or addresses to drop
unwanted junk mail. While this might be nice to filter mail from
known spam domains like "cyberpromo.com", it won't catch faked
headers.
mapSoN must be installed as filter program for your incoming mail,
usually by adding an appropriate entry to your $HOME/.forward file.
This means that mapSoN will get all your incoming mail and it will
decide whether or not to actually deliver it to your mailbox.
. First of all, an user defined ruleset is checked against the
mail. If any keywords or patterns match, the mail will be dealt
with according to your wishes. This is useful to drop some
sender's mail completely, or to sort mail into different mail
folders.
o If no rule matches the mail, mapSoN will check whether the mail
is a reply to an e-mail you sent, or whether it is a reply to a
USENET posting of yours. If it is, the mail will always be
delivered.
o If no signs of a reply-mail can be found, mapSoN will check
whether the sender stated in the From: header has sent you mail
before. If he has, the mail will pass. If this is the first time
you receive an e-mail from this address, though, mapSoN will
delay the delivery of the mail and spool it in your home
directory. Then it will send a short notice to the address the
mail comes from, which may look like this:
From: Peter Simons
To: never_mailed@me.before
Subject: [mapSoN] Request for Confirmation
mapSoN-Confirm-Cookie:
The person who tried to contact you will then reply to this
"request for confirmation", citing the cookie stated in the mail.
When your mapSoN receives this confirmation mail, it will deliver
the spooled mail into your folder. Furthermore, the address will be
added to the database, so that mail from this person will pass
directly in future.
If no confirmation mail arrives within a certain time, mapSoN can
either delete the spooled mails, or send them to a special folder,
or whatever you prefer.
3.15 Software: spamgard
[similar to MapSon]
ftp://ftp.netcom.com/pub/wj/wje/release/sg-howto
...sppamgard(tm) screens from your e-mail unsolicited bulk mail. It
does this in a way that you only have to change things if you have
a new person from whom you _do_ want to receive mail; you don't
have to change things every time a spamster thinks of a new trick
to pull, or a new spamster comes along. And spamgard(tm) is
designed so that those who aren't in your "Good Guys" list can get
mail to you anyway until you put them there. The instructions for
them to get mail to you are simple and newbie-tested, but will
still keep out bulk mail. If you're on a mailing list you _want_ to
be on, there are provisions for accepting all mail from a set of
mailing lists that you specify.
3.16 Software: Spam Be Gone
"Spam Be Gone"
http://www.internz.com/SpamBeGone/
...uses machine learning and artificial intelligence technologies
to examine incoming mail messages and determine their
priority... is more than just a Spam filter, it's a general purpose
mail message prioritiser. You train the system, telling it which
are good, and which are bad messages. As Spam Be Gone! learns it
becomes customised for each individual user.
PM-L W. Wesley Groleau comments:
.> They only distribute binaries, and I'm paranoid. Anyone able to
.> convince me it's not really a Trojan Horse to collect addresses of
.> spam-haters or something even worse?
I did some sleuthing. I am 95% convinced that SpamBeGone is not
a front or cover for any spammer(s). To protect the author's
privacy, I won't say why I'm convinced or how I got the info.
Sorry. If you're paranoid like me, you'll have to do your own
sleuthing before you use it.
I'm also convinced SpamBeGone's theory is sound. I won't judge
the implementation until I've used it for a while.
PM-L R Lindberg & E Winnie comments:
I have to agree with the recent comments about Spam Be Gone, I
found it tends to be inaccurate. I first set it up about a week
ago, followed the directions and trained it on several (15 to 20)
messages. One from each list we get, and the remainder from my
logs of SPAM messages.
The first day it missed about half the SPAM, and nailed about 1/3
of the real messages. So I tuned the key-words a bit, trained it
on about 100 more SPAMs and trained it on all the good messages
it nailed. Since then it has nailed every SPAM received, however
the second day it nailed about 20% of the good messages, which I
then trained it to like. Since then it has been nailing about
10% of the good messages, despite continual training. I also
added every list to the address book, and it still nails posts
from this list, and my wife's lace list.
I even went through my entire log of SPAM and trained it on every
one that didn't come out a 5 (bad). Being the kind of person I
am, I also checked after I trained it, and found four SPAMs, the
despite my training it that they were bad (5) came out as not so
bad (4). I don't dare kill 4's as far too much of my mail (like
this list) ends up as 4's.
For me, this program is not ready for prime time. If the comments
are correct that it only learns on Subject and From headers, it's
not even worth trying. Since lists use the TO and CC headers to
be identified, and there are several excellent other headers
(X-Advertisement comes to mind) that would be assests for killing
SPAM.
3.17 Software: ClearMail
http://www.clearmail.com/ 1998-08-27
Scott R Carter
ClearMail offers individuals some very strong control over spam
through a quite unique concept. The software includes Procmail,
Perl and C code. System Requirements include:
ClearMail helps to control spam by allowing a user to classify
e-mail as high or low priority based on an Address Book or "White
List" of known senders. Unknown senders can also send high priority
mail by including a special Mail Key (token) in their message
(initial message from unknown sender without valid Key results in a
bounceback message with instructions).
What makes ClearMail different from similar concepts is that
spammers are not able to easily obtain the Mail Key to bypass the `
system because it is conveyed as an image.
o Unix operating system
o Shell accounts for users
o Individual .forward, .procmailrc files
o Sendmail
o Procmail
o Perl
o Public Web server
3.18 Software: TinyGnus - Emacs Gnus plug-in
http://poboxes.com/jari.aalto/ema-tiny.html
Platform: win32 and Unix Emacs versions.
*TinyGnus* Is Emacs lisp extension package that integrated directly
to Gnus mail/newsreaders. It includes simple but efective UBE
fighting hotkeys that make it possible to complain bunch of UBE
messages a once. Features:
o USER MUST DECIDE WHICH IS *ube* MAIL.
o User selects messages that are ube with Gnus select commands.
o Hotkey C-c ' u examines messages' headers and runs `nslookup'
for each Received header to determine *abuse* *spam* and
*postmaster* addresses where to send the complaint.
4.0 Procmail pointers
4.1 Where to get procmail binary
ftp://ftp.informatik.rwth-aachen.de/pub/packages/procmail/
On-Line manual: http://www.voicenet.com/~dfma/intro.html
4.2 Where is procmail developed
Philip Guenther is currently taking care of and
coordinating procmail bug fixes. Please send any procmail bugs to
the mailing list or to . The development mailing
list is running SmarList at . Further
patch and bug info can be found at:
http://www.gac.edu/~guenther/procmail/todo.html
http://www.gac.edu/~guenther/procmail/warts.html
Newest Procmail code:
http://www.procmail.org/
ftp://ftp.procmail.org/
4.3 About procmail's Y2K compliance
Please consult Philip Guenther for more up to date
details. Philip is the Procmail maintainer currently.
[1998-09-23 Bennett Todd in Message-Id:
<19980923164230.C30594@fcmc.com>] Well, from a simple ogle of the
grep over the sources, it looks like there may be a Y2038 problem
in the autoconf test code: unsigned otimet = time(). And another,
possibly less likely to express itself, in formail.c: unsigned long
h1 = time(). Those could express themselves when 32-bit signed
time_t wraps; long before then the time_t define should have been
changed to something that is bigger, even if it's "long long". The
above type-mixes may fail to profit from a suitably redefined
time_t, and so may overflow on 2038.
I don't see any Y2K problems, though. And email headers use
four-digit years pretty consistently, so that should all be cool.
This estimation doesn't constitute an in-depth Y2k audit of
procmail, but the source code to procmail is ... kinda dense for
in-depth auditing.
[1998-09-25 Bennett Todd Message-Id:
<19980925093902.B12428@fcmc.com>] As I see it there are at least
three measures that a whole email system, taken in aggregate, could
use for Y2K checking. First, capture a vast cross-section of
traffic and make sure no email software is using 2-digit years. I
don't recall having seen any, but it's still worth checking.
Second, generate a load of traffic with 2000 and 2001 dates and
shove it through all the channels. And third, run all the systems
end-to-end with their system clocks rolling over the millenium.
4.4 Procmail mailing lists
Traffic in this list is about 5-20 messages per day. Do not join
if you can't handle that much traffic. The list is run by SmartList,
which is a procmail-based list management and distribution package.
._MailingList_: questions/answers
.subscription requests
.digest request
To get off the procmail mailing list
To get off the list: send a message to *procmail-request* with:
unsubscribe user@domain in the subject line
unsubscribe first line in the body
If that fails, try email to
(purportedly that should
go to a person). See also the original subscriptions message that
you will received http://www.iki.fi/~era/procmail/welcome.txt
4.5 Procmail recipe modules and faqs
Procmail is discussed in usenet newsgroup *comp.mail.misc*.
"Procmail archive"
ftp://ftp.informatik.rwth-aachen.de:/pub/packages/procmail/
Articles from procmail mailing list: covers from 1994-08 to 1995-05
(A .gz file: ~2Meg when uncompressed)
And latest articles can be found here, hosted by Achim Bohnet
Covers from 1995-10 to the present day.
. The www page has nice search capabilities.
http://www.rosat.mpe-garching.mpg.de/mailing-lists/procmail/
http://www.rosat.mpe-garching.mpg.de/~ach/exmh/archive/procmail/
"Era's Procmail faq"
http://www.iki.fi/~era/procmail/mini-faq.html
http://www.dcs.ed.ac.uk/~procmail/faq/ [mirror]
Also available by email, the ITEM can be: links.html, mini-faq.html,
procmail-faq
To:
Subject: send ITEM
"Era's Procmail Link collections"
http://www.iki.fi/~era/procmail/links.html
...A page full of good links to the world of procmail
"Catherine's Getting Started With Procmail"
http://shell3.ba.best.com/~ariel/nospam/proctut.shtml
This is a quick tutorial intended to get a procmail neophyte
started using procmail with as little trouble and fuss as possible.
"Joe Gross's short Procmail tutorial"
http://www.procmail.net/
...Using procmail and a
feature of ph you can set up your own mailing list without
needing root on your own machine.
"Unix manpages"
http://www.xs4all.nl/~pater/manpages/
...If you don't have procmail manpages at hand, check this site.
It contains a wealth of Unix related manpages online.
Jeroen Paternostre
4.6 Procmail mode for Emacs
If you use Emacs, please download the Procmail
programming mode, `tinypm.el'. Lint is included in there and it can
auto-correct mistakes on the fly. You can get it from the mentioned
_uta_ ftp site. Here is an example of its output:
*** 1997-11-24 22:13 (pm.lint) 3.11pre7 tinypm.el 1.80
cd /users/jaalto/junk/
pm.lint:010: Warning, no right hand variable found. ([$`']
pm.lint:055: Pedantic, flag orer style is not standard `hW:'
pm.lint:060: Warning, message dropped to folder, you need lock.
pm.lint:062: Warning, recipe with "|" may need `w' flag.
pm.lint:073: Warning, Formail used but no `f' flag found.
4.7 Procmail module list
Where to get the modules
The UBE stop procmail modules are not listed here. See pointers in
"procmail code" section later.
o All pm-ja*.rc modules are in Jari's procmail kit.
The Procmail code library page is at
http://www.procmail.org/jari/pm-code.html
o Other modules are by Alan Stebbens http://reality.sgi.com/aks/
o 1998-12-08 Eli the Bearded <*@qz.to> announced in
comp.mail.misc that he had made his procmail modules available
at http://www.qz.to/eli/src/procmail/. You may find
interesting procmail code there but the modules themselves are not
general purpose *plug-in* modules that you could use right
away. Some functionality included:
Inline decoding of MIME text attachments (rc.mime-decode)
Cleansing of obscure "Re:" formats in subject (rc.pre-list)
Nifty autoresponder (rc.qz-2)
Sophisticated dupicate email catching (rc.dupes)
Example of using my mail bouncer (rc.lists-out)
Detection of some classes of autoreplies (rc.daemon)
Various junk mail filtering (rc.filter)
Daily log files (rc.vars)
Terminology
*subroutine* = A piece of code that gets something in `INPUT' and
responds with `OUTPUT'. Subroutine is not message specific.
*recipe* = A piece of code that is somewhat self contained:
It reads something from the message or does something
according to matches in message. Recipe may be message-specific.
Foreword to using modules
In the module listing, some of the modules are recipes and some can
be considered subroutines. Let's take the address exploder module
that was discussed a while ago. First, visualise following familiar
programming language pseudo code:
(ret-val1, ret-val2 ...) = Function( arg1, arg2, arg3 ...)
*Function* may return multiple arguments and multiple arguments can
be passed to it. Clear so far. Let's show how this applies to
procmail modules:
RC_FUNCTION = $PMSRC/pm-xxx.rc # name the subroutine/module
RC_FUNCTION2 = ...
INPUT = "value" # Set the arg1 for module
INCLUDERC = $RC_FUNCTION # Call Function( $arg1 )
:0 # Examine function ret val
* ERROR ?? yes
...
This should be pretty clear too. You just have to look into the
subroutine/module which you intend to use, to find out what
arguments it wants which you _need_ _to_ set (INPUT) before calling
it. The documentation also tells you what values are returned, e.g.
one of them was ERROR.
If it were recipe/module, the call would be almost the same, but
instead of returning values, the recipe/module most likely does
something to your message or writes something to the data files
etc. A *Recipe/module* is much higher level, because it may
call multiple subroutine/modules. The distinction between
subroutine and recipe module type is not crystal clear, but I hope
the above will clarify a bit the Procmail module/subroutine/recipe
concept.
Header file modules
These are like #include .h files in C, they define common
variables, but do not contain actual code.
o pm-javar.rc -- Defines standard variables: SPC WSPC NSPC SPCL and
perl styled \s \d \D \w \W and \a \A (alphabetic characters only)
o headers.rc -- From Alan's procmail-lib. Define standard regexp
and macros: address, from, to, cc, list_precedence
General modules
o *pm-jafrom.rc* -- Derive FROM field without calling `formail'
unnecessarily. If all else fails, use formail.
o *get-from.rc* -- From Alan's procmail-lib. get the "best" From
address. Sets FROM and FRIENDLY, the latter being the "friendly"
user name sans address.
o *pm-jaaddr.rc* -- Subroutine to extract various email components
from INPUT. Like address=foo@some.com, net=com, account=foo...
o *pm-jastore.rc* -- Subroutine for general mailbox delivery.
Define MBOX as the folder where to drop
message and this subroutine will store it appropriately.
Supports single mboxes, ".gz" mbox files, directory files and
MH folders with rcvstore.
Date and time handling
For these, you get the date string from somewhere, then feed
it to some of these subroutines:
o *pm-jatime.rc* -- a low-level subroutine. Parse time "hh:mm:ss"
from variable INPUT
o *pm-jadate1.rc* -- a low-level subroutine. Parse date
"Tue, 31 Dec 1997 19:32:57" from variable INPUT
o *pm-jadate2.rc* -- a low-level subroutine. Parse ISO standard date
"1997-11-01 19:32:57" from variable INPUT
o *pm-jadate3.rc* -- a low-level subroutine. Parse date
Tue Nov 25 19:32:57 from variable INPUT
o *pm-jadate4.rc* -- Call shell command "date" once to construct RFC
"Tue, 31 Dec 1997 19:32:57" and parse the YY MM HH and other
values. You usually use this subroutine if you can't get the date
anywhere else.
Date and time handling
You use these recipes to get the date directly from the message:
o *pm-jadate.rc* -- higher-level recipe. Read date from message's
headers: From_ Received, or call shell `date' if none succeeds.
o *date.rc* -- higher-level recipe.
From Alan's procmail-lib: parse date or from headers
Resent-Date:, Date, and From
Forwarding and account modules
o *pm-japop3.rc* -- Pop3 movemail implemented with procmail. You can
send a "pop3" request to move your messages from account X to
account Y. Each message is send separately. This recipe listens
to "pop3" requests.
o *pm-jafwd.rc* -- control forwarding remotely. You can change the
forward address with a "control message" or turn
forwarding on/off with a "control message"
o *pm-japing.rc* -- Send short reply when subject contains the word
"ping" to show that the account is up and email address is
valid.
o *correct-addr.rc* -- From alan's procmail lib. To help forward mail
from an OLD address to a NEW address, and do some mailing list
mail management. This recipe file is intended to make it easy
for users to forward their mail from their old address to a new
address, and, at the same time, educate their correspondents
about it by CC'ing them with the mail.
Vacation modules
o *pm-javac.rc* -- A framework for your vacation replies. This
recipe will handle the vacation cache and compose an initial
reply; which you only need to fill in. (Like putting vacation
message to the body)
o *ackmail.rc* -- From Alan's procmail lib. procmail rc to
acknowledge mail (with either a vacation message, or an
acknowledgement)
Message-id based modules
o *pm-jadup.rc* -- Handle duplicate messages by Message-Id.
Store duplicate message in separate folder.
o *dupcheck.rc* -- From Alan's procmail-lib. If the current mail has
a "Message-Id:" header, run the mail through "formail -D",
causing duplicate messages to be dropped. Can use MD5 hash in
cache.
Cron modules
o *pm-jacron.rc* -- A framework for your daily cron tasks. This
recipe contains all the needed checks to ensure that your
includerc is called whenever a day changes. (Day change is
subject to messages you receive). Your own cron includerc is
run once a day.
Backup modules
o *pm-jabup.rc* -- Save messages to backup directory and keep only N
messages per day. Idea by John Gianni, packaged by Jari. Note:
The implementation will always call shell for each message you
receive; so using this module is not recommended if you get
many messages per day. Instead, use the cron module to clean
the messages' backup directory only once a day, and not everytime
a message arrives.
Confirmation modules
o *pm-jacookie.rc* -- Handle cookie (unique id) confirmations.
Also known as Procmail authentication service (PAS).
This simple procmail module will accept messages only from
users who have returned a "cookie" key. You can use this to
to protect your mailing list from false "subscribe" messages
or from getting mail from unknown people, typically spammers
who won't send the cookie back to you to "validate" themselves.
Uses subroutine pm-jacookie1.rc, which generates the unique
cookie; CRC 32 by default.
o See also Michelle's confirmation module for SmartList
File Servers
o *pm-jasrv.rc* -- A Mime Procmail file server (MPFS) It contains
all the instructions and supports several MIME encoding types:
text/plain and gzip. The keyword SEND is configurable. You
can set up as many file servers as you need to different
directories by changing the SEND keyword. MPFS supports
password for file access.
o *commands.rc* -- From Alan's procmail-lib, check for commands
in the subject line. Handles commands (send|get)
[help|info|procmail info|procmail lib|procmailrc] and a few
others.
o *send-file.rc* is a very simplistic piece of procmail code
to send file (non-MIME support) requested in subject line.
http://www.universe.digex.net/~mbr/unix/send-file.html
Mime modules
o *pm-jamime.rc* -- Subroutine to read MIME headers and put the
mime version, boundary string, content-type information to
variables.
o *pm-jamime-decode.rc* -- recipe to decode quoted-printable
or base64 encoding in the body.
o *pm-jamime-kill.rc* -- Recipe for attachment killing: wipes out the
extra mime cruft leaving only the plain text. Applications for
killing: ms-tnef attachment (MS Explorer 7k),
html attachments (netscape, MS Express) vcard (Netscape),
PCX attachment (Lotus Notes).
o *pm-jamime-save.rc* -- Recipe for saving simple file attachment.
When you receive _ONE_ file attachment in a message, this
recipe can save it in a separate directory. The content is
also decoded (base64,qp) while saving.
Filtering message body or headers
o *pm-jadaemon.rc* -- Handle DAEMON messages by changing subject to
reflect a) the error reason b) to whom the message was originally
sent c) original subject sent and what was the subject. Store the
DAEMON messages to separate folder.
o *pm-jasubject.rc* -- Standardize Subject "Re[32]: FW: Sv: message"
or any other derivate to de facto "Re: message"
o *pm-janetmind.rc* -- Reformat http://minder.netmind.com/ messages,
The default 4k message is shortened to a few important lines.
Miscellaneus modules
o *pm-jaempty.rc* -- check if message body is empty (nothing
relevant). Define variable BODY_EMPTY to "yes" or "no" if
message is empty.
o *pm-janslookup.rc* -- Run nslookup on given address. If you
compose return address with "formail -rt -x To:" you can
verify if domain is registered before sending reply. Uses cache
for already looked up domains.
o *guess-mua.rc* -- Guess the Mail User Agent and set MUA:
MH,PINE,MAIL
Mailing list modules
o *Microlist* a small mailing list module by david hunt
...This version contains vars set for my environment and needs,
and requires resetting of those vars before use. Its exact
function and use will remain a mystery until I get a readme
file written for it. If anyone wants to use it, I suggest you
write to me first. If anyone has any suggestions or criticisms
(no matter how harsh) please write
http://www.west.net/~dh/homedir/microlist/microlist4.3
o *pm-jalist.rc* -- Subroutine to extract mailing list name from
message. Do you need to add a new recipe to your .procmailrc
every time you subscribe to new mailing list? If you do,
take a look at this module, which examines the message and
defines variable `LIST' to hold the mailing list name. You
can use it directly to save the messages adaptively to
correct folders. No more hand work and manual storing
of mailing list messages.
4.8 Where to get Procmail code and modules
"Alan's procmail modules"
Send subject "send procmail library" to Alan Stebbens
http://reality.sgi.com/aks/
"pm-code, Jari's Procmail modules"
http://www.procmail.org/jari/ --> See pm-code.zip or *shar* file.
"Elijah's"
http://www.qz.to/~eli/src/procmail/rc.master.html
"Concordia scripts"
http://alcor.concordia.ca/topics/email/auto/procmail/
...We provide sample sets of recipes to get you started. The great
thing about the concordia scripts is the fact that they are
designed to run from a central location and be called from a
.procmailrc installed in the user's ~/home directory.
"Meng on procmail"
http://icg.resnet.upenn.edu/procmail/
http://res2.resnet.upenn.edu/procmail/
...goes into exhaustive detail about how I manage my mailing lists
"David's" David Hunt
...My .procmailrc and .forward files can be viewed at
http://www.west.net/~dh/homedir/pmdir/
4.9 Procmail code to filter UBE
_Sysadms_ _remember_ : Spam filtering is much more efficiently done
in the MTA, especially if you are just looking at From and To lines.
For example, you can setup in Exim a rule that blocks \d.*@aol\.com
(that is any aol.com local part that begins with a digit). AOL
guarantees that _none_ of their addresses begin with a digit. Exim
rejects such bogus addresses at the SMTP level before the message
is received.
"Daniel's smap filter"
1997-09-13 Daniel Smith sent excellent spam filter
called `spamc.rc'. It used some nice heuristics and filters from
various people, including [david] and [philip].
Later Dan made substantial changes to it and the new version is
available from ftp://ftp.bristol.nl/pub/users/DanS/spamcheck
"pm-jaube.rc Jari's ube filter (compiled from others)"
After Daniel Smith posted his spam recipes to procmail mailing
list, Jari investigated them and compiled other recipes to a
general purpose UBE module that needs no special setup and can be
installed via simple INCLUDERC. No additional ube-list files are
used, all UBE detection happens using procmail rules. The module
is included in kit `pm-code.zip'.
"Catherine A. Hampton's Spambouncer"
http://www.best.com/~ariel/nospam/
...The attached set of procmail recipes/filters, which I call
The Spam Bouncer, are for users who are sick of spam (unsolicited
junk email) and want to filter it out of their mail as easily
as possible. These recipes can be used as shared recipes for a
whole system, or by an individual for their own mailbox only.
"Protect yourself from spam: A practical guide to procmail"
http://www.sun.com/sunworldonline/swol-12-1997/swol-12-spam.html
...take you, step by step, through everything you need to know in
order to enlist the aid of a Unix host in filtering unwanted e-mail
traffic. This page is excellent to get you started with procmail
and filtering with simple recipes and how to store messages to
folders. Recommended for newcomers to Procmail.
"Junkfilter" by Gregory Sutter
http://www.pobox.com/~gsutter/junkfilter/
...Junkfilter is a user-configurable procmail-based filter system
for electronic mail. Recipes include checks for forged headers,
key words, common spam domains, relay servers and many others.
"Download procmail spam filters"
http://www.telebyte.com/stopspamr
This is excellent site and contains many other spam stop pointers.
"SpamDunk"
http://www.interlog.com/~waltdnes
http://www.interlog.com/~waltdnes/beta/techie.htm
...This webpage shows a commented example of a working .procmailrc
file that works for me. I have tried to make things as generic as
possible, but there are no guarantees that it will work for anyone
else.
5.0 Dry run testing
5.1 What is dry run testing
It means that you call your procmail test script directly with sample
test mail
% procmail $HOME/pm/pm-test.rc < $HOME/tmp/test-mail.txt
The script pm-test.rc has the procmail recipe you're testing or
improving. The test-mail.txt is any valid email message containing
the headers and body. You can make one with any text editor, e.g.
`vi', `pico' or `emacs' in your Unix system. Here's a
simple test mail skeleton:
From: me@here.com
To: me@here.com (self test)
X-info: I'm just testing
BODY OF MESSAGE SEPARATED BY EMPTY LINE
txt txt txt txt txt txt txt txt txt txt
Remember that you can define environment variables as well in
the dry run call. Here's an example where procmail just executes
the script and does nothing fancy.
% procmail VERBOSE=on DEFAULT=/dev/null \
~/pm/pm-test.rc < ~/txt/test-mail.txt
Suppose the script prints something to logfiles, but you'd instead
like to get it all dumped to screen. No problem, first find out
your tty value by calling `tty' at shell prompt and pass
that on the command line. Here the default LOGFILE is directed
to take care of redirecting "LOG=" commands and statement
"MYTEST_LOG=${MYTEST_LOG:-$HOME/pm/pm-test.log}"
# `tty' tells what to fill in /dev/..
% procmail VERBOSE=on DEFAULT=/dev/null \
LOGFILE=/dev/pts/0 MYTEST_LOG=/dev/pts/0 \
~/pm/pm-test.rc < ~/txt/test-mail.txt
5.2 Why the From field is not okay after dry run
It now says "From foo@bar Mon Sep 8 14:38:06 1997"
[philip] Don't worry about this. It's a side-effect of running the
message through formail after having generated any auto-reply --
the auto-reply generated by "formail -rt" doesn't have a "From "
header (it's pointless for outgoing messages), so the second
formail adds one, not knowing that it'll just be ignored by
sendmail later (well, sendmail will extract the date from it, but
that's ignorable). You only see it because you're saving to a
folder instead of the mailing it.
5.3 Getting default value of a procmail variable
[david] There's always this way to learn a variable's
initial value (note the strong quotes), which Stephen uses to get
procmail's value for $SENDMAIL in the scripts that build SmartList:
procmail LOG='$PATH' DEFAULT=/dev/null /dev/null < /dev/null
Since LOGFILE hasn't been defined, $PATH will be printed to the
screen. One caution: if there are any variables in the definition
of $PATH (such as $HOME), they'll be expanded in the output.
6.0 Things to remember
6.1 Get the newest procmail
Lot of troubles surface only because you have an old procmail version.
Be sure to have the latest which is 3.13.1 since 1999-04-05. Here is
a command to check your procmail version number:
% procmail -v
Knock your sysadm or ISP until he installs this version; don't give
up, if you're serious about using procmail.
6.2 Csh's tilde is not supported
Real csh or Emacs freaks have grown accustomed to using tilde (~)
everywhere, but must drop that habit now. Procmail doesn't support it;
just use `$HOME'. When you write procmail recipes, think *sh* not
*csh*. This mindset will automatically get your brain tuned to the
right programming habits.
6.3 Be sure to write the recipe starting right
The recipe starts with `:0' or just with `:' but the latter one is
somewhat dangerous and easy to miss. Beware writing it `0:' as it
happens easily. The Procmail code checker, Lint, also requires that
you use the `:0' recipe start convention.
[philip] Always put a zero after the colon that begins the recipe. In
the first versions of procmail, you would put the number of
conditions, with a default of 1. That was annoying, and the computer
can do the counting easier, so Stephen made it so that a count of 0
indicates that the conditions are all the lines beginning with a `*'.
The default is one, unless the `a', `A' , `e', or `E' flags is given,
in which case the default is zero. *ALWAYS* *START* a *RECIPE* *WITH*
`:0'.
6.4 Always set SHELL
[faq] If your login shell is a C shell (csh or tcsh), avoid
havoc: as a precaution, always put following at the top of
your .procmailrc.
SHELL = /bin/sh
If system has no /bin/sh and you're forced to use csh/tcsh
[] Csh and tcsh execute the .cshrc
first, THEN if, and only if it is the login shell (not a sub shell)
it executes the .login, which should contain basic important system
setting like `stty' commands. Likewise, bash and ksh users are
taught to define and export PATH in .profile, so our per-shell
startup files would not have clobbered the PATH set in .procmailrc
the way your .cshrc did.
[philip] ...I have been told by other sysadmins that there are
systems on which csh was hacked to source the .login before the
.cshrc. For various reasons I suspect these to be systems based on
older versions of BSD (say, 2.3 BSD).
As for tcsh, the order in which the .login and .cshrc is sourced is
a compile-time option which defaults to the .cshrc (or .tcshrc)
before the .login. There may be some wackos out there who change
the default in memory of the system(s) that they were raised on. I
suggest electroshock as the proper treatment.
...done sys admin on Crays, Convexes, Suns, SGIs, Decs, PC
running BSDI, Linux and Free BSD, and I have never run into a
system where the .cshrc is sourced AFTER the .login. If someone
goes to the trouble to change the order, I would love to know a
valid reason for it.
Procmail won't work well with SHELL set to csh derivate
[1998-08-17 PM-L Volker Kuhlmann]
...The blame lies with procmail and its documentation. Obviously,
procmail is programmed with the assumption that the login shell is
a sh derivative. This assumption is a) not very nice, and b) not
stated in the otherwise very good documentation. Of course a user
can set SHELL to tcsh. If then procmail is too stupid to hack it,
it ought to say so clearly, and the above-mentioned questions of
people using tcsh will disappear from this list. One could also be
nice and point out pitfall (3) mentioned above in the procmail
docs. It is customary to have terminal configuration in .login. If
it is shifted to .cshrc it should be properly surrounded by if ..
endif. Perhaps it is not customary to configure the terminal in
.bashrc (where else then? - only a rhetorical question), but that
is no reason to blame it on tcsh.
My .cshrc only setenvs the environment when it is a login shell
(shell level 1). Obviously procmail runs a login shell. As I said
earlier, there are good reasons for setting a full PATH
independently whether the shell is interactive or not. So, when
procmail executes programs with SHELL=tcsh, PATH is set to the tcsh
defaults. That may or may not be desirable, depending on the
individual case. No problem with that and avoidable (run tcsh with
-f). Nice if it was in the procmail docs.
But then, the PATH getting clobbered is not the point here (just a
side-effect I didn't realise until 2 people pointed it out).
6.5 Check and set PATH
[jari] It is very likely that the default PATH environment variable
that your .procmailrc sees it not enough. To play safe, so that all
the needed binaries can be found when escaping to shell in
.procmailrc, set the `PATH' variable as a very first statement.
Here is one example that I use for HP-9 HP-10 and in SUN-OS.
You can add paths that don't exist, that way you can use the
same .procmail on multiple servers (On HP and SUN as I do)
PATH = $HOME/bin:\
/usr/contrib/bin:\
/bin:/usr/bin:/usr/lib:/usr/ucb:/usr/sbin:\
/usr/local/bin:/opt/local/bin:\
/vol/bin:/vol/lib:/vol/local/bin:${PATH}
[Richard] It is dangerous to have many directories in the PATH,
especially if you do not control the content of any of them. A
sysadmin could put a newer, incompatible version of a program you
rely upon in one of them and you cause difficult-to-diagnose
problems. It may make more sense to link the binaries you need into
your own ~/bin directory and include just that in your PATH.
[jari] In principle I agree with Richard's advice, but in practice
the newer version of the program seldom breaks the procmail code
you have written. It depends on your "threat level": be more
cautious and use Rik's advice; alternatively trust the system and
adapt to (rare) changes. Your call.
6.6 Keep the log on all the time
It's best that you put these variables at the very start of
your .procmailrc. When you start using procmail, you also want to know
all the time what's happening there and why your recipes
didn't work as expected. The answer to almost all your questions can
be found in the log file. As the log file will grow to be quite big,
remember to set up a cron job to keep it moderate size.
LOGFILE = $PMSRC/pm.log
LOGABSTRACT = "all"
VERBOSE = "on"
6.7 Never add a trailing slash for directories
[philip] Drop the trailing slash: it'll choke if you ever end up on
Apollo's DomainOS where double slashes are network references. If
the directory has a trailing slash, it will choke
on most OSes (they treat it like "/.").
DIR = /full/path/to/www/directory/ # Wait...
FILE = $ARCHIVEDIR/file # Ouch !
6.8 Remember what term DELIVERED means
[alan] When procmail delivers a piece of mail, whether to a
file or a pipe-command, if the write succeeds, then the mail is
considered to have been delivered, and processing stops with that
recipe file. Here is the relevant text from man page:
...There are two kinds of recipes: delivering and non-delivering
recipes. If a delivering recipe is found to match, procmail
considers the mail (you guessed it) delivered and will cease
processing the rcfile after having successfully executed the
action line of the recipe. If a non-delivering recipe is found to
match, processing of the rcfile will continue after the action
line of this recipe has been executed.
6.9 Beware putting comment in wrong place
You like commenting a lot, sticking them everywhere possible?
Yes, I do that too, and got into trouble because one is not that
free to comment code in procmail. Pay attention to the following
example
:0 # comment, nice tune...
* condition # OUCH, Ouch, ouch. This comment must not be here!!
# Hm, Old procmail versions don't understand this
# Are you sure you want to put comments inside
# Condition line?
* condition
{ # comment ok
# comment ok
:0 # comment ok
/dev/null # comment ok
} # comment ok
So, the place to watch is the *condition* line. Some later procmail
versions promised to correct this misfeature, but it never came
true. No procmail exists yet that allows putting comments
on the same line with a condition clause.
6.10 Brace placement
Be careful with your braces and remember that old procmail
versions aren't as forgiving as newest version. Below you see
classical "Test OK condition first, and if that fails then do
something else". See the side comments.
:0
* condition
# No space allowed here!
{} # Wrong, at least _one_ empty space
:0 E
{do_something } # Again mistake, must have surrounding spaces
6.11 Local lockfile usage
Lockfiles are only needed when procmail is doing something that
should be serialized, i.e., when only one process at a time should
be doing it.
This generally means that any time you write to a file, you should
have a locallock, preferably based on the name of the file being
written to. Forwarding actions ('!'), and 99% of all filters don't
need lockfiles. However, if a filter action writes to a file while
filtering, then you may need a lock. Procmail always does kernel
locking when it writes mail to files via simple file actions. So
even if you forgot the lock colon, procmail tries to play safe if
kernel locking has been compiled in.
Beware misplacing the lock colon(:)
:0: a # Ouch! Wrong unless you want a lockfile named a
:0 a: # Okay.
Note that in delivering recipes where you manually write the
content, you must use local lockfile with `>' token, because
procmail can't determine lock by itself. It can only determine the
lockfile from the `>>' token. [stephen] However, putting a
lockfile on a recipe like this is, of course, utterly useless. So
you might as well omit the locking entirely.
# Save last body of message to file mail.body
:0 b: mail.body$LOCKEXT
| cat > mail.body
o If the command line in the procmail rcfile contains ">>",
a name for the local lockfile will be implicit, and the second
colon alone is enough.
o If the command doesn't write to a file, or doesn't write to the
same file as anything else (including a matching letter that makes
procmail run the same command) that might run at the same time,
the local lockfile is unnecessary.
[philip] Watch this too. A nesting block that does not launch
a clone cannot take a local lockfile on the recipe that starts the
braces. A nesting block that does launch a clone can. (see
the error)
:0: file$LOCKEXT
{
# error: "procmail: Extraneous locallockfile ignored"
# - This lock file will be ignored
# - If the recipes inside the braces try to use file.lck
# as a lockfile, then you'll have a deadlock situation.
:0 :
/tmp/tmp.mbx
}
Let me also explain why the `w' is so important. Notice, that the
two here are equivalent. The `W' here is implicit. _NOTE_: this is
only true on the recipe that opens a nested block. On a recipe with
a program, forward, or delivery action, `W'' is different from `w'
is different from missing both.
:0 c: file$LOCKEXT :0 Wc: file$LOCKEXT
{ ... } { ... }
To quote the comment in source code, "try and protect the user from
his blissful ignorance". The parent will always wait for the cloned
child to exit when a lockfile is involved. The only question is
whether or not it should be logged. If you want failure of the
cloned child to be logged, then you should use the `w' flag, ala:
:0 wc: file$LOCKEXT
{ ... }
A local lockfile can be used to lock a clone; the parent procmail
will remove it when the clone exits (thus it serves as a global
lockfile for the clone). If the braced block does not launch a
clone, asking for a local lockfile generates an error.
6.12 Global lockfile
[david] If you want to block everything while the recipe runs, even
during the _conditions_, use global lock. For example in this
construct the `formail' which updates the message-id cache file
must be protected with a global lockfile.
MID_CACHE_LEN = 8192
MID_CACHE_FILE = $PMSRC/msgid.cache
MID_CACHE_LOCK = $PMSRC/msgid.cache$LOCKEXT
LOCKFILE = $MID_CACHE_LOCK
:0
* ^Message-ID:
* ? $FORMAIL -D $MID_CACHE_LEN $MID_CACHE_FILE
{
LOG = "dupecheck: discarded $MESSAGEID from $FROM $NL"
:0 # no lockfile !
$DUPLICATE_MBOX
}
LOCKFILE # kill variable
You cannot use local lockfile as below:
:0 : $MID_CACHE_FILE$LOCKEXT
* ^Message-ID:
* ? $FORMAIL -D $MID_CACHE_LEN $MID_CACHE_FILE
because the local lockfile named on the flag line will be created
only if the conditions have matched and the action is attempted.
One more note: watch carefully, that there is _no_ `:' lock when
delivering to `DUPLICATE_MBOX' because the outer global lockfile
already prevents all other procmail instances from executing this
part of the recipe.
6.13 Gee, where do I put all those ! * $ ??
Ahem. I can't tell you exactly what to do or how to write your own
procmail recipes, but I can tell how I'm writing them. Here is my
condition line token order:
* $ ! ? BH VAR ?? test
That won't say much unless I give you something to compare with.
Here is one perfectly valid rule, but not my style
:0
*$ ^Subject:.*$VAR
*! ^From:.*some
*B ! ?? match-the-string-in-body
*$? $IS_EXIST $FILE
*VARIABLE ?? set
I prefer lining up things in the condition lines. The first column is
reserved for dollar sign, the second for *not* operator and so on.
The important thing is that I can see at a glance if I have set the
variable expansion dollar in the line (leftmost).
:0
*$ ^Subject:.*$VAR
* ! ^From:.*some
* ! B ?? match-the-string-in-body
*$ ? $IS_EXIST $FILE
* VARIABLE ?? set
6.14 Sending automatic reply, use X-loop header
Do not send automatic reply without checking "! ^FROM_DAEMON"
condition and always include `X-Loop' header and check its existence
to prevent mail loops
:0
* conditions-for-auto-reply
*$ ! ^$MY_XLOOP
* ! ^FROM_DAEMON
| $FORMAIL -A "$MY-XLOOP" ...other-headers...
6.15 Avoid extra shell layer (check command for SHELLMETAS)
[dan] It is very important to study your shell command calls and try to
save the overload of the extra layer of shell. It may be extra work
once when you write your rcfile but it saves effort on each piece of
arriving email. When procmail sees a character from `SHELLMETAS', it
runs
# Default SHELLMETAS: &|<>~;?*[
# Default $SHELLFLAGS: -c
% $SHELL $SHELLFLAGS "command -opts args"
instead of
% command -opts args
That is because procmail's ability to invoke other programs does not
include filename globbing ([, *, ?), backgrounding (&), piping
(|), succession (;), nor conditional succession (&&, ||). If it
sees any of those characters (before expanding variables), it hands the
job over to a shell.
Sometimes those characters appear in arguments to a command without
having their shell meta meaning and procmail really could invoke the
command directly without the shell. You can see the distinction in a
verbose logfile: if procmail runs the command itself, it logs
Executing "command,-opts,args"
with a comma between each positional parameter, but if it calls a
shell, the original spacing from the rcfile appears unchanged in
the logfile:
Executing "command -opts args"
So, if you know you won't be needing shell expansion, wrap your
shell calls with this:
savedMetas = $SHELLMETAS
SHELLMETAS # Kill variable
..command that does not need shell expansion features..
SHELLMETAS = $savedMetas
6.16 Think what shell commands you use
For every message, procmail launches the processes you have put into
your .procmailrc. If you haven't paid attention to optimization
before, now it's serious time to take a magnifying glass and check
every recipe and the processes in them. When you write you private
shell scripts, the performance hit is not so important, but for
mail delivery, the matter is totally different. First, let's see
some programs and sizes: The following is from HP-UX 10, where the
binaries seem to include debug and symbol table code.
131072 Aug 21 1996 /usr/bin/awk
196608 Oct 1 1996 /usr/bin/sort
245760 Jun 10 1996 /usr/bin/grep
262144 Jun 10 1996 /usr/bin/sed
303552 Dec 7 1995 /usr/local/bin/gawk
544768 Jun 10 1996 /usr/contrib/bin/perl [perl 4.36]
822232 Aug 25 13:58 /opt/local/bin/perl5.00401
text data bss
awk: 72727 + 51316 + 15317 = 139360
sort: 173225 + 18496 + 183076 = 374797
sed: 237248 + 16992 + 56252 = 310492
grep: 221591 + 16176 + 53816 = 291583
perl4: 502220 + 36044 + 65632 = 603896
perl5: 633812 + 69612 + 2385 = 705809
gawk: 160018 + 5264 + 7168 = 172450
The binary siszes above are not the typical cases: these are from
another system
4 Sep 28 14:25 /usr/local/bin/awk -> gawk
32768 Nov 16 1996 /usr/bin/grep
49152 Nov 16 1996 /usr/bin/sed
114688 Oct 20 1996 /usr/local/contrib/gnu/bin/grep
155648 Nov 16 1996 /usr/bin/awk
155648 Nov 16 1996 /usr/bin/nawk
221184 Nov 16 1996 /usr/bin/gawk
311296 Jan 27 1997 /usr/local/bin/gawk
958464 Nov 2 16:34 /usr/local/contrib/bin/perl
1196032 Sep 14 1996 /usr/local/bin/perl
Stan Ryckman wants you to know that:
Comparing byte sizes on disk means nothing here... these
things may or may not have been stripped. Any symbol tables included
in the byte counts you see above won't affect process start-up time.
The `size' command will give a better handle on what will be needed
in starting a process. The three segments may each have their own
overhead, though, and the relative contributions of those segments
to startup time may well be system-dependent.
Hm. Can we draw some conclusion? Not anything definitive, but at
least something:
o While sed and grep may be bigger than awk in some systems, this
is an exception. They are usually much smaller and fast to use.
o But complex commands that would require many processes to be
chained together, like `grep -v | grep | sed' combination could
be usually accomplished with one awk call. Ask somewhere how to
do it with awk if you don't know the language, it's quite alike
perl
o Don't use anything else but standard awk, _gawk_ and _nawk_
are bigger and may not be found on all systems.
o Avoid perl at all costs; it's many times (6) bigger than awk.
Perl is slow-to start up, due to intermediate compilation
process at startup.
o Remember that if procmail is running in a dedicated mail host, it
probably doesn't even have any goodies installed, just the boring
standard versions; which may not be even the same as what you see
on current host. e.g. My mail host is running HPUX-9, while my
login is on HPUX-10. They have very different installations.
Here are some more programs. Don't even think of extracting fields with
`grep' or `awk', like "grep Subject", because `formail' is
much smaller and more optimized for tasks like that.
37007 Sep 5 15:53 /usr/local/bin/formail # 3.11pre7
28672 Jun 10 1996 /usr/bin/tr
20480 Jun 10 1996 /usr/bin/tail
20480 Jun 10 1996 /usr/bin/cat
20480 Sep 26 1996 /usr/bin/expr
16384 Jun 10 1996 /usr/bin/head
16384 Jun 10 1996 /usr/bin/cut
16384 Jun 10 1996 /usr/bin/date
16384 Jun 10 1996 /usr/bin/uniq
16384 Jun 10 1996 /usr/bin/wc
12288 Jun 10 1996 /usr/bin/echo
6.17 Using absolute paths when calling a shell program
Shell programmers know that if you use absolute path when you call
the executable, shell doesn't have to search through long list of
directories in $PATH. This may speed up shell scripts remarkably.
The correct way to use such an optimization is to define variables to
those programs.
Hm, should you use such optimization in your procmail code? That's
two folded question and I....would say yes and no. How many
shell calls do you have? Do you use grep or formail a lot? Then you
could optimize these calls. To be portable, define variables for
executables:
# perhaps defined in separate INCLUDERC
#
# INCLUDERC = $PMSRC/pm-mydefaults.rc
FORMAIL = /usr/local/bin/formail
GREP = /bin/grep
DATE = /bin/date
:0 fhw
| $FORMAIL -rt
And when you port your .procmailrc to different environment that
has different paths, you could use this recipe in addition to one
just mentioned above:
FORMAIL = ...as above
:0
* HOST ?? second-host
{
# In this host the paths are different. Reset.
$FORMAIL = "formail"
$GREP = "grep"
$DATE = "date"
}
6.18 Disabling a recipe temporarily
If you have a recipe that you would like to disable for a while,
there is an easy way. Just add the "false" condition line before
any other conditions. The "!" also nicely visually flags that
"this recipe is NOT used".
# This recipe stops at "!" and doesn't get past it.
:0
* !
* condition
* condition
{
...
}
6.19 Keep message backup, no matter what
It's good to have a safety measure in your .procmailrc.
Although you are an expert and have checked your recipes 10 times,
there is still a chance that something breaks. One morning, when you
browse your *BIFF* reminder log; you notice "Hm, there is that
interesting message but it was not filed, where is it?". And when
you go to study the procmail logs (you do keep the log going all
the time) and it hits you: "Gosh; a mistake in my script! Message was
fed to malicious pipe and I had that `i' flag there... *sniff*".
And you greatly regret you didn't back up the message in the first
place.
So, before your procmail does anything to your message, put the
message into some folder which is regularly expired. For example I
use Emacs Gnus to handle the expiring. One could also use a cron job
instead. Then you can relax knowing your email is safe.
SPOOL = $HOME/Mail/spool
# Backup storage
# - This could be directory too. In that case you could use
# cron job to expire old messages at regular intervals
# - For once a day expiration, see procmail module list
# and pm-jacron.rc
BUP_SPOOL = $SPOOL/junk.bup.spool
:0 c:
$BUP_SPOOL
Naturally you can filter out mailing list messages from the backup,
because losing one or two (hundred) of them may not be that serious.
Maybe you could use two backup spools, one for mailing lists and the
other for your non-list messages.
:0 c:
* ! mailing-list1|mailing-list2
$BUP_SPOOL
If you have the date variables set up as described below, you
could also create a backup folder per day:
$BUP_SPOOL = $SPOOL/$YYYY$MM$DD
This makes it very easy to delete backups that are older than
a given number of days, either manually or through a cron job.
6.20 Order of the procmail recipes
When you start writing a lot of procmail recipes, you soon find out
that it matters a great deal in which order your put your recipes. When
each group of recipes starts growing too big, it's good practice to
move each group to a separate rc file. Here is one recommended order:
- backup important messages
- cron-subroutine
- handle duplicate messages
- handle DAEMON MESSAGES
- handle plus addressed message (RFC plus or sendmail plus addresses)
- handle server requests (file server, ping responder...)
- drop MAILING LIST messages
- send possible vacation replies only after all above
- apply kill file
- detect mime and format or modify the message body
- save private messages
- and last: FILTER UBE.
The backup, cron and duplicate handling go naturally to the beginning
of your .procmailrc. Next comes a grey area where Daemon, plus handling
(#REF #using_rfc_comment_trick_for; Note plus;); and server messages can
be put.
Mailing lists should be handled as early as possible, but after the
server messages, because you want your services handled first.
Do not send vacation replies before you have handled mailing lists
to prevent annoying vacation replies to lists.
After that you are left with "known" private messages and those of
unknown origin. A kill file (to block based on sender) for rapid
spammers, who send you message or several per day need to be
checked before checking other messages.
Last but not least: Put your UBE checkers to the end to avoid mishits
of valid mail. DO NOT SEND AUTOMATIC COMPLAINT BACK. Drop the
UBE to a folder, manually select the messages that need actions
and send message to postmasters in the Received chain explaining that
their mail relay has been hijacked.
7.0 Procmail flags
7.1 The order of the flags
Order does not matter of course, but here is one stylistic suggestion.
The idea here is that the most important flags are put to the left,
like giving priority 1 for `aAeE', which affect the recipe
immediately. Priority 2 has been given to flag `f', which tells if
a recipe filters something. Also (h)eader and (b)ody should
immediately follow `f', this is considered priority 3. In the
middle there are other flags, and last flag is `c', which ends the
recipe, or allows it to continue. In addition according to [david]:
"...I'm quite sure that putting anything other than the opening
colon and the number to the left of `AaEe' will cause an
error."
:0 aAeE HBD fhb wWir c: LOCKFILE
| | | | |
| | | | (c)ontinue or (c)lone flag last.
| | | (w)ait and other flags
| | (f)ilter flag and to filter what: (h)ead or (b)ody
| (H)eader and (B)ody match, possibly case sensitive (D)
The `process' flags first. (A)nd or (E)lse recipe
You can write the flags side by side
:0Afhw:$MYLOCK$LOCKEXT
Or, as I prefer, leave flags in their own slot for more
distinctive separation. Note that $LOCKEXT must be next to $MYLOCK,
because it contains string ".lock".
:0 A HB fhw: $MYLOCK$LOCKEXT
7.2 Flag w and recipe with |
[alan] If the filter program exits with a 0 status (0 == okay), then
procmail will replace the original input body with the output of the
filter program. If the filter program exits with anything but zero,
procmail will report an "error" to the log, and "recover" the input
(not filter it)
[david] I am very sure that that's the case _only_ if you have the
`w' or `W' flag on the filtering recipe. Without `w' or `W',
procmail won't care about a bad exit status from the filter and will
replace the filtered portion with whatever standard output the
filter produced. It may still report an error to the log but it
won't recover the previous text. This, for example, will destroy the
body of a message, even without `i':
:0 fb
| false
With this, however, procmail will recover the original body:
:0 fbW # same results even if we add `i'
| false
[stephen] No, not on all occasions. Procmail will not care about the
exitcode here. However, if procmail detects a write error, it *will*
recover (because of the missing `i' flag). Procmail will only detect
a write error in such a case if the mail is long enough and does not
fit in the pipe buffer that's in the kernel (typically 10KB).
7.3 Flag w, lockfile and recipe with |
[manual] In order to make sure the lockfile is not removed until the
pipe has finished, you have to specify option `w' otherwise the
lockfile would be removed as soon as the pipe has accepted the
mail. So if you see anything that looks like ">" or ">>" in your
recipe, then that should immediately ring your bells. immediately
check that you have included the `w' flag _and_ the lockfile `:'.
:0 hwc: headc$LOCKEXT
* !^FROM_MAILER
| uncompress headc.Z; cat >> headc; compress headc
7.4 Flag f and w together
The w tells Procmail to hang around and wait for the script to
finish. [Wouldn't you think this ought to be implied by the f
already?]
[david] Of course the `f' flag is enough to make procmail wait for
the filter to finish, but the `w' means something more: to wait to
learn the exit code of the filtering command. If sed fails with a
syntax error and gives no output, without `W' or `w' procmail would
happily accept the null output as the results of the filter and
go on reading recipes for the now body-less message. On the other
hand, with `W' or `w' sed will respond to a non-zero exit code by
recovering the unfiltered text.
7.5 Flags h and b
[david] `hb' is the default; you need to use `h' only when you
don't want `b' or vice versa. You can think of it this way: `h'
means "lose the body" and `b' means "lose the header," but the two
together cancel each other out.
[philip] `hb' (feeding whole message) is the default for actions.
You need to specify `h' without `b' if you want the action applied
only to the head. `H' is the default for conditions. You need to
specify `HB' or `BH' if you want to test a condition against the
entire message.
7.6 Flag h and sinking to /dev/null
When you drop something to /dev/null, use the h flag so that
procmail does not unnecessarily try to feed whole message there.
:0 h
* condition
/dev/null
[philip] Procmail knows that it shouldn't create a locallock on
/dev/null and that it shouldn't kernel lock /dev/null, and it knows
to write it "raw" (no "From " escaping or appended newline). This
means that procmail simply opens /dev/null, does its write with
one system call, and closes it.
I'm not sure if adding the `h' flag makes a real difference on
modern UNIX kernels. I suppose it depends on how optimized the
write() data is and in particular, whether a user-space to
kernel-space copy is _required_, or whether it's delayed. If it's
delayed then the code for handling /dev/null would presumably not
do it, and the size of the write wouldn't actually matter.
7.7 Flag i and pipe flag f
Flag `i' is useless in mailbox deliveries.
[faq] The following will work some of the time, when the message is
short enough, but that's a coincidence. With a longer message,
though, Unix starts paying attention to what is happening, because
it will have to buffer some of the data, and then when the buffered
data is never read, an error occurs. The error is passed back to
Procmail, and Procmail tries to be nice and give you back your
original message as it was before this malicious program truncated
it. Never mind that in this case you wanted to truncate the
data. Anyway, the fix is easy: Just add an `:i' flag to the recipe
( `:0fbwi' instead of `:0fbw') to make Procmail ignore the error.
:0 fbw
* condition
| malicious-pipe
[dan] here's why the `i' flag is needed (courtesy of Stephan): You
told procmail to filter the entire mail (header and body), so it
does and it attempts to write out header and body to the filter.
Then procmail notices that not the entire body is being consumed.
Procmail, being rather paranoid when it comes to delivery of mail
assumes something went wrong and considers this a failure of the
filter.
:0 fbwi
| head -2
7.8 Flag r
[philip] Procmail automatically turns on the `r' (raw mode) flag for
deliveries to /dev/null, so there's no need to do it yourself.
:0 r # you can leave out the `r'
* condition
/dev/null
[david] You can use the `r' flag (for raw mode) on every recipe
where you do not want a From_ line added. I'm assuming that there
isn't one already there; the `r' flag keeps procmail from making
sure that there are a From_ line at the top and a blank line at the
bottom, but it will not make procmail remove them if they are
already present. Also, be careful to use the `-f' option on all
calls to formail so that formail won't add a From_ line.
Someone who didn't need From_ lines -- I forget who -- found it
annoying to put `r' onto every recipe and altered the source to
prevent procmail from adding From_ lines at all, ever. I think a
better idea would be a procmailrc Boolean to enable or disable them
for all recipes without affecting other users. (Then perhaps we'd
need a reverse `r' flag to undo raw mode for one recipe at a time?)
7.9 Flag c's background
...Interesting. My vision of `c' is to think of CONTINUE
with message processing afterwards even if conditions matched.
[david] Precisely: when you have braces, thinking "continue"
instead of "copy" or "clone" can get you into trouble.
Early versions of procmail, before braces and before cloning,
called the `c' flag "continue" in their documentation; I think it
is still called that in the source.
When Stephen introduced braces (but not cloning at this point), it
was of course implicit that an action line of "{" was
non-delivering, and a `c' was extraneous. People put c's there
because they wanted procmail to continue to the recipes inside the
braces on a match, and procmail brushed it off with an "extraneous
c-flag" warning. No harm done.
When Stephen introduced cloning, though, I was rather upset that he
was giving double duty to `c' instead of introducing something new
like `C' for it, especially because people who absolutely wanted no
clone but intended the recipes inside the braces to run in the same
invocation of procmail as everything else were mistakenly putting
c's on their braces to make sure procmail would "continue". People
would (and did) get double deliveries.
Roman Czyborra, though, said that if you consider `c' to stand for
"copy", that covers both uses of `c': provide a copy to a simple
recipe or, if there are braces, to a clone procmail that will
handle the recipes inside the braces. Stephen agreed and changed
the documentation accordingly.
Longtime users of procmail and people who read old docs may still
think of it as "continue", but since the introduction of clones,
that is not a good way to look at it. "Copy" is much safer.
7.10 Flag c before nested block forks a child
[alan] The combination of a nested block and the `c' flag causes
procmail to fork a child process for the nested block, while the
parent skips over it and continues on. The child process doesn't
necessarily stop unless a *delivering* recipe (without the `c' flag)
action succeeds.
7.11 Flag c and understanding possible forking penalty
... I run shell commands that need not to be serialized, so
instead of doing the standard way:
:0 hic # nbr.1 / standard way
| command
I assume I can avoid the extra fork caused by (c)lone flag
altogether by using these. Any difference between these two?
:0 # nbr.2 / alternative
* ? command
{ } # ...No-op, Procmail syntax requires this
dummy = `command` # nbr.3 / alternative
[philip] There is a misunderstanding here. Let me clarify:
Procmail only forks a full-blown clone on a recipe with the 'c'
flag whose action is a nested block.
If it's a simple mailbox deliver, pipe, or forward action then
procmail does not fork a 'clone' (for pipe and forward actions
procmail does have to fork, but only so it can execute the
action). `nbr.1' and `nbr.2' take the same number of forks to
execute. They also take the same effective number of writes
(in case you're concerned about that). The latter also
requires that procmail wait for the command to finish.
`nbr.3' is worse than the above two, as procmail has to not
only wait for the command to complete but also save the output
into the named variable.
7.12 Flags before nested block
Given the following recipe, let's examine the flag part
:0 $FLAGS
{
do-something
}
[david] `HB' `AaEe' and `D' affect the conditions and
thus are meaningful when the action is to open a brace. `HB' and
`D' would be meaningless, of course, on any unconditional recipe, but
they should not cause error messages.
Generally, flags that affect actions are invalid there, and `bhfi'
and `r' always are, but the others are partial exceptions: if you
are using `c' to launch a clone, then `w' `W' and a local lockfile can
be meaningful. If there is no `c', then `w' `W' and a local lockfile
are invalid at the opening of a braced block.
7.13 Flags aAeE tutorial
[david] `AaEe' are mutually exclusive and no more than one should
ever appear on a single recipe. [philip] Actually, this is not
true. e does not work with `E' or `a' (and procmail gives a warning
if you try), and `A' is redundant if a is given, but at least some
of the other combination make sense and work.
o *A* = try this recipe if the conditions succeeded on the most
recent recipe at that nesting level that did not itself have an
A nor an a
o *a* = same as `A', but moreover the action must have succeeded
on the most recently tried recipe at that nesting level
o *e* = Almost like `A', try this recipe if the conditions matched
but the action failed on the most recently tried (not skipped)
recipe at this nesting level. universe, `e' is the opposite of `a'.
`e' only looks backwards past `E' recipes that were skipped
because of their `E'. It doesn't care whether a previous recipe
had an `A' or `a' flag.
o *E* = try this recipe if the conditions have failed on the most
recent recipe at that nesting level that did not have an `E' and
on since then every recipe at that level that did have an `E';
essentially opposite of `A'
These mnemonics might help:
o *A:* if you did the recipe at the start of the chain, try this one
(A)lso
o *a:* if the last action at that nesting level was (a)ccomplished)
o *e:* if the last action at that nesting level (e)rred
o *E:* (E)lse because the conditions down the chain so far have not
matched. Or "try this recipe unless the last tried recipe matched".
# [philip] demonstrates `e'
:0 : # match, but action fails
/etc/hosts/foo
:0 A # no match
* -1^0
/dev/null
:0 e # this is skipped because the last tried recipe didn't match
{
...whatever
}
How they interact with one another when used consecutively has not
been fully tested to my knowledge. Consider this:
:0
* conditions
non-delivering-action1
:0 a
action2
:0 e
action3
Is action3 done if action2 failed or if action1 failed (or perhaps
in both situations)? [philip] Action 3 is only done if action2 failed.
If the answer is action2, does this work to get action3 done if
action1 failed? I think it does, but does it also run action3 if
the conditions didn't match on the first recipe? [philip] Yes, and
yes.
:0 # [david]
* conditions
non-delivering action1
:0a
action2
:0E
action3
[philip] If that's not what you want, combine some flags:
:0
* conditions
non-delivering action1
:0 Ae
action3
:0 a
action2
If the conditions match, action1 will be executed. action3 will
then execute if action1 failed, otherwise action2 will be executed
[if action1 succeeded].
[david] I know what this structure does because I use it:
:0
* conditions
non-delivering action1
:0A
action2
:0E
non-delivering action3
:0A
action 4
If the conditions match, action1 and action2 are performed and
action4 is not (of course action3 is not either), even if action2
is non-delivering; if they fail, action3 and action4 are performed.
The `A' on the fourth recipe refers back to the third and no farther.
But I don't know about this:
:0
* conditions
non-delivering action1
:0A
* more conditions
action2
:0E
non-delivering action3
:0A
action 4
Now, suppose the conditions on the first recipe match but those on
the second recipe do not match. Would the third recipe (and thus
the fourth one) be attempted? I would expect so. [philip] Yes. The
last tried recipe didn't match, therefore the `E' flag will be
triggered.
If that isn't what you want, you can prevent it this way:
:0
* conditions
{
:0
non-delivering-action1
:0
* more-conditions
action2
}
:0 E # ignores mismatch inside braces, looks only at same level
non-delivering action3
:0 A
action4
If that is what you want, you can be positive this way:
# if action2 is non-delivering or vulnerable to error that
# would cause fall-through
DID2 # Kill variable
:0
* conditions
non-delivering-action1
:0 A
action3
:0
* ! DID2 ?? (.)
non-delivering-action3
:0 A
action4
# if action2 is delivering and sure to succeed
:0
* conditions
non-delivering-action1
:0 A
* more-conditions
action2
:0
non-delivering-action3
:0 A
action4
[philip] or those who are interested, I'll note that there are only
3 combinations of the `a', `A', `e', and `E' flags that aren't
either illegal or redundant. They are `Ae', `aE', and `AE'. I've
shown a use for `Ae' up above. Here's an example of `AE':
:0
* condition1
non-delivering action1
:0 A
* condition2
non-delivering action2
:0 AE
action3
action3 will only be executed if condition1 matched but condition2
didn't match. Without the A flag, action3 would be executed if
either of them failed. This can also be done with a instead of A
with analogous results.
Procmail's "flow-control" flags may not be particularly easy to
describe in straight terms (and this can all be made more
complicated by throwing in a more varied mix of delivering vs
non-delivering recipes), but I've found that it usually does what I
expect it to do, and when it doesn't or I'm in doubt or I want to
be particularly clear, I can always fallback to doing it explicitly
via nesting blocks. Pick your poison...
8.0 Matching and regexps (regular expressions)
8.1 Philosophy of abstraction in regexps
Here are two ways to view or write regexps. Make up your own mind.
People who are in favor of writing pure native regexps in the
recipes:
[ ]<[ ]*("([^"\]|\\.)*"|[-!#-'*+/-9=?A-Z^-~]+)... # "
o I'm not planning on "maintaining" that code, as the syntax for
XXX will not ever change <>>
o I some how doubt that anyone else will change that regexp more than
trivially
o If none of your other regexps use the categorical variables, and
you're not changing the regexp, then what's the point?
The variablized version will be slower, and will clutter the
environment with subprocesses.
Where someone that immediately wants to abstract things says
(This is from philip's great Message-Id matching recipe)
dq = '"' # (literal) double-quote
bw = "\\" # (literal) backwhack
atom = "[-!#-'*+/-9=?A-Z^-~]+"
word = "($atom|$dq([^$dq\]|$bw.)*$dq)'
local_part = "$word($s\.$s$word)*"
$s<$s$local_part... # ignore comment here
....abstraction: It makes code clearer when you break it
to manageable parts, which possibly surfaces reusable parts. It
also makes thing look simpler, and enables even novices
to understand what's going on there. After we're not
connected to the net anymore, others could possibly understand
it too.
So, naturally we can't agree with any of the previously mentioned
arguments presented for keeping regexp "in pure native format".
o Although you won't maintain it, it's an example for others. What
you post first, people will save it to their mailboxes and
circulate elsewhere in the net: "Hey, I've saved this, try it"
o You can write cryptic regexps or break them into parts where
the whole looks much simpler. Consider novice's welfare :-)
This has nothing to do with the "It never changes in my lifetime".
o The speed penalty imposed by additional variables is not
something we can measure in practice. CPU won't even hiccup.
An extra `formail' call in your recipes is 10x as expensive as
100 variables. (I don't know how to measure that, but launching
a shell and creating a process is a much more expensive task).
o Cluttering the env process? C'm on. That won't matter either.
No outside process uses lowercase environment names, or then it
must be real special program. So called "cluttering" of
environment space is also no-issue. CPU won't even get a hiccup
for that.
8.2 Matches are not case-sensitive
Okay, okay; if you read the manual you knew that already. But
sometimes someone with years of experience with Unix may take it for
granted that procmail would be case-sensitive as the rest of the
unix tools are. Use the `D' flag to turn on case-sensitivity.
8.3 Procmail uses multiline matches
Procmail uses multiline matches by default. This means that ^ and $
match a newline, even in the middle of a regexp. Now you know this,
you can easily interpret e.g. `$[^>]' as: `a newline followed by a
line not starting with a `>'.
If you put a '$' after the '\/' match token then procmail will
include the matched newline if there's one there. Solution? Don't
put a dollar sign there unless you really want a newline, use period
that matches all but newline:
:0 B
* ^Search-string: \/.+
8.4 Headers are folded before matching
If you have a header that continues on separate lines, you don't have
to worry about the linefeeds. Procmail silently folds the header onto
one line, before matching it
Received: from unknown (HELO Desktop01) (208.11.179.72) by
palm.bythehand.net with SMTP; 4 Dec 1997 23:29:09 -0000
:0 # note, match on continuation line
* ^Received:.*bythehand\.
8.5 Improving Space-Tab syndrome
Procmail doesn't know about standard escape codes like `\t' and `\n'
or [\0x00-\0x133]:
# Not what you think # You have to write: space + tab
[ \t] [ ]
But using the space+tab is not very readable and it's a very error
prone construct. I suggest using the following to improve the
readability:
WSPC = " " # whitespace = space + tab
SPC = "[$WSPC]" # regexp whitespace, the short name
# SPC was chosen because you use this
# a lot in condition lines.
NSPC = "[^$WSPC]" # negation of whitespace
# match anything except space and tab
*$ var ?? $NSPC
# match anything ecxept space and tab and newline
*$ ! var ?? ($SPC|$)
But you cannot use newline inside brackets.
WSPCL = " "'
'
# Won't work although WSPCL definition is correct.
*$ var ?? [$WSPCL]
Instead use variable syntax:
SPCNL = "($SPC|$)" # space + tab + newline
If you absolutely need a range of characters, see if you have `echo'
command in your system to define variables like this:
NUL_CHAR = `echo \\00`
DEL_CHAR = `echo \\0177`
REGEXP_NON_7BIT = "[^$NUL_CHAR-$DEL_CHAR]"
8.6 Handling exclamation character
[philip] you do need the first backslash, to keep procmail from
considering the backslash as a request to invert the sense of the
match. For example, these two conditions are equivalent:
* ! 200^1 foo
* 200^1 ! foo
Therefore, a leading '!' must either be backslashed, enclosed in
either parens or brackets (I suspect that parens would be more
efficient), or prefaced with an empty pair of parens. I would
recommend writing the condition with one of these:
* 200^1 \!!!!
* 200^1 ()!!!!
* 200^1 (!!!!)
8.7 Rules for generating a character class
In a "character class" (things between "[" and "]"), metacharacters
don't need to be escaped. Well, a backslash is an exception.
e.g. [$[^\\] would match any one of the literal characters dollar,
opening bracket, caret, and backslash.
o To match "])" use [])]
o To match "[(" use [[)]
o To include a literal ^ must not be first
o To include a literal - must be first, last or \-
o To include a literal \ you must use \\
o To include a literal ] must be first
o To include a literal [ ( ) or $ just use it anywhere
[elijah] If you are inverting a character class "first" means just
after the(^). So the character class that contains everything but ]
^ and - must look like this:
[^]^-]
[david] What if I want literal $ inside bracket? A $ inside
brackets, unless it begins a variable name and the "$" modifier is
on, always means a literal dollar sign. It cannot mean a newline if
it appears inside brackets. A good way to keep it exempt from "$"
interpretation is to put it last inside the brackets (unless one
also need to include a literal hyphen and one can't put the hyphen
first; then you'll need to escape the dollar sign with a backslash
and put the hyphen last -- well, you could alternatively escape the
hyphen, I guess), because procmail knows that "$]" cannot possibly
be a reference to a variable.
General guideline:
o ($) always matches a newline, with or without "$" interpretation;
o [$] always matches a dollar sign, with or w/o "$" interpretation;
8.8 Matching space at the end of condition
[david] If you need to have tab or space at the end of condition line
you can use these:
* rest of string .*
* rest of string[ ]
* (rest of string )
* rest of string ()
* rest of string( ) # I prefer this one
[philip] From my looking at the source, the last two should be
equal in efficiency, and except for a trace difference in regcomp
time, should match at the same speed as a solitary trailing blank.
The character class version [ ] will be slower.
Of course, I suspect that neither you nor your sysadmin will ever
notice the difference in speed, and given that 99% of all systems are
I/O bound and not CPU bound, the system is incredibly unlikely to
notice either. I can't complain though, as I also go to various
extremes to seek out every last bit of possible performance. Ah well.
The first one would be slower yet, though perhaps no slower than the
bracket form.
8.9 Beware leading backslash
I am trying to come up with a procmail recipe that among other
things should have the condition 'body does not contain a
particular word'. Here is what I tried:
* ! B ?? \
[david] You have fallen into the leading backslash problem, If the
first character of a regexp is a backslash, procmail takes it as "end
of leading whitespace" and strips it. What you coded means "a less-than
sign, then the word, then any non-word character." (It also prevents
the less-than sign from being taken as a size operator.) Unless the
non-word character immediately to the left of the word was a less-than
sign, that regexp would fail (and thus the condition would pass). Try
this:
* ! B ?? ()\
This would work too:
* ! B ?? \\
but in a casual reading it would look like "literal backslash,
less-than sign, the word, word boundary character," so we on the list
generally recommend the empty parentheses.
Do note that the difference in meaning of \< and \> in procmail (where
they must match a non-word character) from their meaning in perl and
egrep (where they match the zero-width transition into and out of a
word respectively) does not come into play here. Because procmail's \<
and \> can match newlines (both real and putative), it rarely is a
factor. It's a problem only when a single character has to serve both
as the ending boundary of one word an also the opening boundary of
another. Well, it's also a problem when you have one as the last
character to the right of \/, but that's easily solved.
8.10 Correct use of TO Macro
o `TO' is not a normal regular expression; it is a special
procmail expression that is designed to catch any destination
specification. For details, see the miscellaneous section of
the `procmailrc(5)' man pages.
o Prefer `TO_' instead of `TO' if you have new procmail. `TO_' is
better because TO used to be too loose
o Please remember to write `^TO', with the anchor in it.
o Do not put a space between the caret (^) and the word `TO' in
`^TO'.
o Do not put a space between the `^TO' and the text that you are
matching on; it must be `^TOtext' If this bothers you, you can
use `TO()text' instead to get better separation of text.
o Both letters in `TO' must be capitalized.
8.11 Procmail's regexp engine
[philip] procmail's regexp engine has no special optimization
for anchoring against the beginning of the line. Most program that
have such an optimization have it because they need the line
distinction for other reasons (for example, grep by default prints
the entire line containing a match). Procmail has no such other
reason, so it treats newline like any other plain character in the
regexp. There should be no speed difference as long as procmail
can say: "the first character I see must be a 'foo'". Note that
case insensitivity is handled by making everything lowercase, so a
letter being first doesn't bring in the spectre of character-classes
or anything like that.
.> recipe may have just changed the size of the head, procmail
.> cannot keep a byte-count pointer nor a line-count pointer to
.> where the body begins but must scan through the head to find the
.> blank line at the neck before it begins a body search.
Procmail does this when it reads in the head, not when it goes to
search the body, so that cost can't be avoided. Let me repeat; that
searching the body is no slower than searching the header, if we
forget the minimum impact of the size of these two.
8.12 Procmail and egrep differences
[By david]
o ^ and $ are non-zero-width and anchor to real or putative
newlines (rather than to the zero-width start and end of a line);
o An initial ^^ or a final ^^ anchors to the opening or closing
putative newline respectively;
o ^ and $ in the middle of a procmailrc regexp match to an embedded
newline (and must be escaped to match to a caret or a dollar sign);
o \< and \> are non-zero-width and match to a character that
wouldn't be in a word (or to a real or putative newline) [rather
than to the zero-width transition into or out of a word]; it
always matches one non-word character. It will fail when there is
no whitespace after the colon. This is rather pathological but
still perfectly compliant with RFC822. For this reason,
you should use (.*\<)? instead of just .*\< after the colon that
terminates a header field name:
^Subject:.*\ # Wrong
^Subject:(.*\<)?humor\> # Right, notice ?
o *, ?, and + in the absence of \/ are stingy rather than greedy,
and that generally won't matter, but in the presence of \/ they
are stingy to the left of \/ and greedy to the right of \/,
while in most applications the leftmost wildcard on a line is
the greediest and greed decreases from left to right.
8.13 Understanding procmail's minimal matching (stingy vs. greedy)
...I want to have a procmail recipe that will save certain mail to
folders where the folder name (always a number) is specified in
the subject.
:0 :
* ^Subject: *\/[0-9]*
$HOME/Mail/$MATCH
[philip]...and this won't quite work. For a subject with a space
after the tab, the '*' on the left hand side will be matched
minimally (zero times), and then the stuff on the right hand side
will be matched maximally, but starting at the space still, which
will match nothing. This is a case were procmail's minimal matching
can cause massive confusion and frustration. The solution is
usually the following:
FORCE THE RIGHT HAND SIDE TO MATCH AT LEAST ONE CHARACTER
By Changing the recipe to:
:0 :
* ^Subject: *\/[0-9]+
$HOME/folders/$MATCH
it'll work, because then the left hand side will have to match all
the way up to the first digit (but not the digit itself). If you
follow the rule in caps then you'll almost always be able to ignore
procmail's weirdness in this area.
[david] And examine how procmail matches "Subject: Keywords 9999"
* ^Subject:.*Keywords.*\/[0-9]*
procmail: Match on "^Subject:.*Keywords.*\/[0-9]*"
procmail: Matched ""
The right side was as greedy as it could be; the problem is that we
seem to expect greed on the left as well. MATCH is set to null, in
contrary to our expectation. It is not a bug but rather a frequently
misunderstood effect of the way extraction is advertised to operate.
Remember that only the right side is greedy; the left side is
stingy, and left-side stinginess takes precedence over right-side
greed.
Extraction is implemented this way: the entire expression, left and
right, is pinned to the shortest possible match; then the division
mark is placed and the right side is repinned to the longest
possible match starting at the division. The tricky part is to
remember that the division is marked during the stingy stage.
If the expression is
^Subject:.*Keywords.*\/[0-9]*
and the text is
Subject:Keywords9999
then the shortest possible match to the entirety is
Subject:Keywords
because ".*" and "[0-9]*" both match to null. Then the division
mark is placed on the space after "Keywords" and procmail looks for
the longest possible match to [0-9]* starting with that space.
That, again, is null, so MATCH is set to null.
We see that it works as expected if regexp is changed to this:
^Subject:.*Keywords.*\/[0-9]+
That is a whole other ball of wax. Now the shortest match to the
entirety is
Subject:Keywords9
and the division mark is placed at the 9. Then procmail refigures
the longest match to the right side starting at the division mark
and sets MATCH=9999. However here
^Subject:.*Keywords\/.*[0-9]*
the second ".*" would have reached not just up to the digits but
through them to the end of the line. MATCH would contain the rest of
all of it matched to ".*" plus null match "[0-9]*".
[for curious reader]
Given line
Subject: Keywords 9999
the second, which differs only by inserting the extraction marker,
would not match and would not set $MATCH:
^Subject: Keywords *9999 # matches ok
^Subject: Keywords *\/9999 # won't !
because the left side would be matched to "Subject:
Keywords" and the immediately following text, " 9999", did not match
the right side. It would actually make the condition fail and keep
the recipe from executing. It took a lot of circuitous coding to
allow for not knowing in advance exactly how many spaces there would
be before the digits.
Call it counterintuitive, but it's not a bug. General advice:
always make sure that the right side cannot match null or that the
last element of the left side cannot match null. Or in other words:
force the right-hand side of the \/ to match at least one character.
8.14 Explaining \/ and ()\/
`MATCH' strips all leading blank lines in 3.11pre7
[david] \/ with nothing to the left of it means "one foreslash". To
start a condition with the extraction operator, use ()\/ or \\/;
the latter looks counter intuitively like "literal backslash and
literal foreslash" (as it would mean if it appeared farther along
in the regexp), so most of us prefer the former.
*$ var ?? $s+\/$d+ # ok, \/ in the middle
*$ var ?? \/$d+ # Wrong, when \/ is at the beginning
*$ var ?? ()\/$d+ # No ok, () at the beginning
8.15 Explaining ^^ and ^
[philip] Procmail doesn't think *lines* when it matches; but it
concatenates all lines together and then runs the regexp
engine. This may be a bit surprising, but consider the following where
we want to discard any message that is likely a html advertisement
# Body consists entirely of html code
# something which'll match any message which has ""
# in the body
:0 B:
*$ $s*
html.mbox
The condition test is applied to the entire body. If you want to
limit it to match only against the beginning of the body, you have
to say so using the ^^ token, as you discovered. A simple line
anchor (^ or $) just says that there must be a newline (or the
beginning or end of the area being searched) at that particular
point in the text being matched. notice the leading anchors below.
# trap spam where the *very* first line of the body started with
#
:0 B:
*$ ^^$s*
html.mbox
What, exactly, does "Anchor the expression at the very start of
the search area..." i.e. the ^^ ?
[dan] Technically, an opening ^^ anchors to the putative
newline that procmail sees before the first character of the search
area (and a closing ^^ anchors to the putative newline that
procmail sees after the end of the search area). When the search
area is B, that is a point equivalent to the second of the two
adjacent newlines that enclose the empty line that marks the end of
the head.
The reason I'm bringing that up is this: if there are multiple
empty or blank lines between the head and the body, ^^ will mark
the start of the second of those lines, not the start of the first
line of the body that contains some text.
So if you want to test whether is the first printing text
in the body, even if it is not necessarily flush left on the very
first line, you might need a condition like the following, where
there is space/pipe/tab/pipe/dollar.
*$ B ?? ^^$SPCNL*
8.16 ANDing traditionally
Erm, you knew this already if you read the man pages. Stacking
condition lines one after another does the AND operation, where
all of the conditions must be present:
* condition1
* condition2
8.17 ORing traditionally
Here is simple OR case. There are some cases where it's impossible
to OR conditions with this style. [philip] knows more about those
cases.
* condition1|condition2
Likewise, two exit code tests can often be ORed like this
* ? command1 || command2
But there are many situations where two tests cannot be ORed by
combining them into one condition:
o a regexp search of one area ORed with a regexp search of a
different area
o a positive regexp search [i.e., for a match to its pattern] ORed
with a negative regexp search [i.e., for the absence of any
match to its pattern]
o an exit code condition ORed with a regexp search condition
o an exit code condition seeking success ORed with an exit code
condition seeking failure
o a size test ORed with anything else (even another size test)
How can I make OR conditions that all use the SAME action? I want
to be able to test for a number of variants on certain requests,
all in one block.
[hal] Yes, this can be easily done
CASE = ""
:0
* case 1 tests
{
CASE = 1
}
:0 E
* case 2 tests
{
CASE = 2
}
:0
* ! CASE ?? ^^^^
{
# real work, perhaps with explicit tests on CASE
}
Case study: Finding text from header and body
[david] In addition to the standard ways of coding OR, here's a
special one for searching the subject and the body for a given word
in either:
* HB ?? ^^(.+$)*(Subject:(.*[^a-z0-9])?|$(.*\<)*)remove\>
If the string doesn't have to be preceded by a word border, it gets
a little simpler:
* HB ?? ^^(.+$)*(Subject:.*|$(.|$))*string
8.18 ORing and score recipe
Once any of the conditions match, the score gets a positive value and
the recipe succeeds. Idea by Erik Selke
[era comments] ...allegedly the scoring system is going to cost you
more than plain old regex matching. Floating-point math and all that,
even if you use extremely simple scoring. Thus, it would probably be
slightly more efficient to do it the De Morgan way.
* 1^0 condition1
* 1^0 condition2
We can now write the previous case stydy (HB ORing traditionally)
with scores. I was tempted to write it like this, when [david]
told me the following.
* 1^0 H ?? match-it
* 1^0 B ?? match-it
[david] That will work, but it isn't the best way to do ORing,
because if a match is found to the first condition procmail still
takes the trouble to test the second one. Better, use the supremum
score on each condition:
$SUPREME = 9876543210
*$ $SUPREME^0 first_condition_to_be_ORed
*$ $SUPREME^0 second_condition_to_be_ORed
* ... etc. ...
*$ $SUPREME^0 last_condition_to_be_ORed
Upon reaching the supreme score, procmail will skip all remaining
weighted conditions on the recipe, deeming them matched. Since all
conditions on this recipe are weighted, once procmail finds one
matched condition it will skip the rest and execute the action.
8.19 ORing by using De Morgan rules
[Tim Pickett ] I thought I'd point out that
there are a few ways to do a logical OR of conditions. Someone posted
a solution here that involved using procmail's scoring system, but I
figured you could do it without scoring by taking advantage of De
Morgan's rule:
a or b is same as not(not a and not b)
or mathematically:
a || b <=> !( !a && !b )
Here's a way to do ORing
:0
* ! condition1
* ! condition2
{ } # official procmail no-op
:0 E
action_on_condition1_or_condition2
9.0 Variables
9.1 Setting and unsetting variables
You have already set variables with the "=" syntax. Variable names
are case sensitive: `var' is different from `VAR'
VAR = /var/tmp # directory
VAR = "this" # literal
VAR = 1
VAR = $FOO # another.
VAR = "$VAR at" # combined with previous value
Unsetting a variable is done like this
VAR # kill variable.
VAR= # same but with old style
VAR = "" # Variable is said to be "null" now
And you can put multiple assignments on the same line
VAR=1 VAR=2 VAR=3
Examine the following, which are all equivalent. The backticks will not
require a shell in the absence of any `SHELLMETAS' so neither of
these will spawn a shell
# _case1_: We Don't care if file exists this time...
VAR = `cat file`
# _case2_: The use of {} is considered "modern"
:0
* condition
{
VAR = `cat file`
}
# _case3_: oldish, and procmail specific and errors have
# been reported if you use this construct.
# Note: There must be no space in "VAR=|"
:0
* condition
VAR=| cat file
9.2 Variable initialisation and sh syntax
Procmail borrows some sh syntax for variable initialisation.
Note that sh's ${var:=default} and ${var=defaultvalue}
syntaxes are not available in a procmail rcfile.
o VAR1 = ${VAR2:-value}
sets VAR1 to VAR2 if VAR2 is set and non-null, and sets VAR1 to
default "value" otherwise
o VAR1 = ${VAR2-value}
sets VAR1 to VAR2 if VAR2 is set, and sets VAR1 to default
otherwise
o VAR1 = ${VAR2:+value}
sets VAR1 to "value" if VAR2 is set and non-null, and sets VAR1
to VAR2 otherwise.
o VAR1 =${VAR2+value}
Sets VAR1 to "value" if VAR2 is set and sets VAR1 to VAR2
otherwise.
And here are the classic usage examples
VAR = ${VAR:-"yes"} # set VAR to default value "yes"
VAR = ${VAR+"yes"} # If VAR contains value, set "yes"
Ever wondered if this calls `date` in all cases?
VAR = ${VAR:-`date`}
No, procmail is smart enough to skip calling `date' if VAR already
had value. It doesn't evaluate the whole line. Below you see what
each initialising operator does. Study it carefully
VAR = "" # Define variable
VAR = ${VAR:-"value1"} # VAR = "value1"
VAR = ""
VAR = ${VAR-"value2"} # VAR = ""
VAR = ""
VAR = ${VAR:+"value3"} # VAR = ""
VAR = ""
VAR = ${VAR+"value4"} # VAR = "value4"
# Note these:
VAR = "val"
VAR = ${VAR:+"value3"} # VAR = "value3"
VAR = "val"
VAR = ${VAR+"value4"} # VAR = "value4"
VAR # kill the variable
VAR = ${VAR:-"value1"} # VAR = "value1"
VAR
VAR = ${VAR-"value2"} # VAR = "value2"
VAR
VAR = ${VAR:+"value3"} # nothing is assigned
VAR
VAR = ${VAR+"value4"} # nothing is assigned
And if you want to choose from several initial values,
you might use the recipe below
instead of the standard var = ${var:-"value"}.
:0
* VAR ?? ^^^^
{
# no value (or was empty), set default value here based on
# some guesses
VAR = "base-default"
:0
* condition
{
VAR = "another-default"
}
...more conditions..
}
You could also use equivalent, but less readable condition line in
previous recipe:
*$ ${VAR:+!}
It works, because if variable contains a value the line expands to
* !
Where "!" is the procmail "false" operation. One more way to do the
same would be, that we require at leastone character to be present.
You could use also regexp (.), which would require at least one
character to be present, but you might not like matching pure spaces.
* ! VAR ?? [a-z]
9.3 Testing variables
If possible, perform positive tests, rather than negative, like below:
* ! TEST_FLAG ?? yes
Alternative with a positive test:
* TEST_FLAG ?? no
To my opinion, this is more
readable. You're free to disagree with me at this point, but all in
all, it's nicer to look at code that has as few ! flags as
possible, especially in variable tests.
[philip] The following fails if the variable is unset or null.
* variable ?? (.)
That was why I'd be better off to use
*$ variable ?? $NSPC
Or
* variable ?? (.|$)
to require that *variable* contain at least one character. But
neither is a way to check whether a variable is set or not, because
each treats a null variable the same as an unset one. This is the
best way I know to check whether a variable is set or not:
*$ ! ${VAR+!}
[] Here is yet another way to test if variable
is set and if it isn't, sets it to a default value.
:0
*$ ! VAR^0
{
VAR = "value"
}
9.4 What does $\VAR mean?
[era and david] Procmail 3.11, $\VAR will escape regex metacharacters.
It should produce a suitably backslash-escaped expression for
Procmail's own use. In addition $\VAR will always begin with leading
empty parentheses.
You can't pass the $\VAR construct to shell programs, because there
is that leading parenthesis. Here's a recipe to standardize the regexp.
You can pass SAFE_REGEXP to an external programs like `sed'.
PROCMAIL_REGEXP = "$\VAR"
:0
* PROCMAIL_REGEXP ?? ^^\(\)\/.*
{
SAFE_REGEXP = "$MATCH"
}
[era] Note that this is slightly inexact; Procmail will
backslash-escape according to Procmail's needs, not sed's. For
example, Procmail doesn't think braces are magic (although that would
be nice to have in Procmail as well) whereas many modern variants of
sed do.
9.5 Common pitfalls when using variables
Procmail is picky and forgives nothing. Here are some of the favourite
mistakes one can make:
$EMAIL = "foo@site.com" # Done Perl lately? Remove that $
# Erm, this is ok, but many procmail recipe writers want to
# take extra precautions and include the regexps in parentheses.
# So, maybe (yabba|dabba|doo) would be more safe
REGEXP = "yabba|dabba|doo"
* Subject:.*$REGEXP # Hey, you need the "*$ Subject..."
*$ $REGEXP ?? hello # surely you meant '* REGEXP ?? hello'
9.6 Quoting: Using single or double quotes
Pay attention to this:
VAR = "you"
NEW = 'hey "$VAR"' # won't extrapolate $VAR; you get literal
NEW = "hey '$VAR'" # extrapolates to: hey 'you'
You can even combine separate words together
VAR = "1 ""and"" 2" # same as "1 and 2"
Don't let these many quotes disturb you, just count the beginning
and ending quotes. Superfluous here, but you may need some similar
construct somewhere else.
VAR = '1 '"'"'and'"'"' 2' # same as: 1 'and' 2
[david] Beware forgetting quotes, like when you'd do
SENDMAILFLAGS = -oQ/var/mqueue.incoming -odq
Procmail translates `!' into | "$SENDMAIL" "$SENDMAILFLAGS" as the
procmailrc(5) man page warns us. By the rules of sh quoting, that
means that shell sees only the first switch
% sendmail -oQ/var/mqueue.incoming
My suggestion: since you need a soft space inside `$SENDMAILFLAGS',
use the quotes when you define `$SENDMAILFLAGS' but do this instead
of using the `!' operator for forwarding:
SENDMAILFLAGS = "-oQ/var/mqueue.incoming -odq"
[Walter Haidinger ] Here's yet another
approach: deliver messages from procmail directly to mailboxes in
all those users' homes. No sendmail involved, _much_ lower loads.
:0:
*
/var/spool/mail/someuser
[philip] Assuming that "someuser" is an actual user in the
password file (I haven't been following this thread, some maybe
that isn't true here), then the following is probably better:
Walter Haidinger comments on this recipe: I'm happy to announce that
this works *really* well. No harm is done to the system-load
anymore. What a relief!
:0 w
* conditions
|procmail -d someuser
That lets procmail's very tricky "screenmailbox()" routine take
care of bogus mailboxes in a secure fashion.
Is that as safe as forwarding? Does another sendmail delivering
to /var/spool/mail/someuser use the same locking mechanism and notice
that mailbox is already locked? I don't want to risk a corrupt
mailbox.
[philip] Sendmail only delivers directly to files through
aliases that say things like:
whatever: /some/local/file
Under normal circumstances, sendmail calls the local mailer to actually
store mail in a file, and since that's procmail (right?), there
shouldn't be a problem. Also, sendmail 8 does kernel-level locking
when it delivers directly.
9.7 Quoting: Passing values to an external program
Remember to include the double quotes when you send variables'
values to the shell programs. Below you see a mistake,
because the content of the SUBJECT is not quoted and
thus not available from perl variable $ARGV[1].
:0
* condition
| perl-script $SUBJECT # mistake; use "$SUBJECT"
There is also another way. If your script can access environment
variables (almost all programs can), then you do not need to pass
the variables on the command line. Above, the SUBJECT is already
in the environment and in perl you can get it.
$SUBJECT = $ENV{SUBJECT}; # or "use Env;" and you see $SUBJECT
Next, do you know what is the difference between these two recipes?
:0
| "command arg1 arg2 arg3"
:0
| command "arg1" "arg2" "arg3"
You guessed it. The first one quotes the entire command and does not do
the right thing, the latter is correct and depending on the content of
argN variables. Anyway, play safe and always add quotes.
Sometimes you need trickier quoting to to get single quotes around
the `arg'. Pay attention to this, because this may be the reason
why your grep command doesn't seem to succeed as you expect.
# If $GREP "$arg" doesn't seem to work
* ? $GREP "'"$arg"'" $DATABASE
9.8 Passing values from an external program
External programs cannot set procmail variables directly. Programs
must write the values to external files and then read the values
from these files. Capturing only one value is easy:
var = `command` # capture STDOUT
But if a program modifies the body and exports some status
information it is trickier. We assume here that the script is
controlled by you and that you have added the switch
--export-status option which causes the program to print
information to a separate file.
LOCKFILE = $HOME/.run$LOCKEXT # protect external file writing
valueFile = $HOME/tmp/values
# modify body, and export status values to external file: one
# value in every line
#
# VALUE1
# VALUE2
# VALUE3
:0 fb
| $NICE script.pl --export-status $valueFile
values = `cat $valueFile`
# Derive values from each line
:0 # line 1
*$ values ?? ^^\/[^$NL]+
{
var1 = $MATCH
}
:0 # line 2
*$ values ?? ^^.*$\/[^$NL]+
{
var2 = $MATCH
}
:0 # line 3
*$ values ?? ^^.*$.*$\/[^$NL]+
{
var3 = $MATCH
}
LOCKFILE # Release lock
[richard] Alternatively write valueFile from your rc or external
program with lines like
PARAM1="value for param 1"
PARAM2="value for param 2"
PARAM3="value for param 3"
and read it with
INCLUDERC $valueFile
Now there is no need to worry about synchronizing the read with the
lines, or about adding new parameters, since each is labeled in
valueFile.
9.9 Incrementing a variable by a value N
[dan, phil and Richard] Here's a recipe for incrementing a variable
by a value N. If $VAR is not a number, we get an error. Note that
if $VAR + $N is not greater than 0, this recipe will not change the
value of VAR if the assignment happens inside braces. You must
place the assignment after the closing curly brace.
:0
*$ $VAR ^0
*$ $N ^0
{ } # procmail no-op
VAR = $=
9.10 Comparing values
It's too expensive to call the shell's `test' function to do
[-lt|-eq|-gt] because you can do the same with procmail. The
do-something below is run if SCORE <= MAXIMUM. The recipe simply
subtracts SCORE from MAXIMUM and determines if the result is
positive.
:0
*$ -$SCORE ^0
*$ $MAXIMUM ^0
{
.. do-something
}
[idea by era] it's getting slightly cumbersome if it's between MIN
and MAX:
:0
*$ $SCORE ^0
*$ -$MIN ^0
{
dummy # no-op, just for the LOG
:0
*$ -$SCORE ^0
*$ $MAX ^0
{
suitable
}
}
Eg. When values are MIN=1, MAX=5, SCORE=4
procmail: Assigning "SCORE=4"
procmail: Score: 4 4 ""
procmail: Score: -1 3 ""
procmail: Assigning "dummy"
procmail: Score: -4 -4 ""
procmail: Score: 5 1 ""
procmail: Assigning "suitable"
9.11 Strings: How many characters are there in a given string?
# 1998-06-23 PM-L [walter]
:0
* 1^1 VAR ?? .
{ }
LENGTH = $
9.12 Strings: How to strip trailing newline.
Suppose you have used regexp, which left newline($) in the `MATCH'.
If you wonder why the recipe works, remind yourself that regexp
operator "." never matches a newline.
:0
* VAR ?? ^^\/.+
{
VAR = $MATCH
}
9.13 Strings: deriving the last N characters of a string.
# 1998-06-23 PM-L [walter] Note the use of
# the $ sign below to anchor to end-of-string...
#
# For last 2 characters use * VAR ?? ()\/..$
# For last 5 characters use * VAR ?? ()\/.....$
:0 # Last character
* VAR ?? ()\/.$
{
TAIL = $MATCH
}
9.14 Strings: Getting partial matches from a string.
[dan] Getting a match to the right is quite easy with procmail's
`match' operator.
VAR = "1234567890"
:0
* VAR ?? ()\/3.*
{
result = $MATCH # now 34567890
}
but deleting 2 characters from the end is nearly impossible without
forking an outside process. The cheapest might be `expr' because it
doesn't need a shell to pipe `echo' to it (as `sed' would and I
believe `perl' would):
# by resetting the shellmetas, this will only call
# `expr'. If we wouldn't have fiddled with shellmetas,
# this would have called two processes: sh + expr
saved = $SHELLMETAS
SHELLMETAS
result = `expr "$VAR" : '\(.*\)..'` # now 12345678
SHELLMETAS = $saved
ksh or bash could do it as well:
# semicolon to force invoking a shell, actually
# first question mark will force a shell already.
saved = $SHELL
SHELL = /bins/sh
result = `echo ${VAR%??} ;`
SHELL = $saved
Now, if you know that the last two characters will be "90", that's
different. Of course, this totally screws up if the third-to-last
character is a 9.
:0
* VAR ?? ()\/.*[^0]
* MATCH ?? ()\/.*[^9]
{
result = $MATCH # now 12345678
}
[jari] Comments: If a shell must be used, then `awk' is a good tool for
simple string manipulation. Its startup time is faster that perl's
whose overhead is due to internal compilation. `awk' also consumes
less recourses overall than `perl'. Following will only work if VAR
is a string of continuous block of characters. (ARGV[1] can be used)
saved = $SHELLMETAS
SHELLMETAS
VAR = ` awk 'BEGIN{ v = ARGV[1]; \
print substr(v,1,length(v)-2); exit }' \
"$VAR" \
`
SHELLMETAS = $saved
This version requires _some_ file, any file, so that we get awk
started. In the previous code all the work was done in the BEGIN
block and no file was ever opened.
saved = $SHELLMETAS
SHELLMETAS
VAR = ` awk '{print substr(v,1,length(v)-2); exit }' \
v="$VAR" /etc/passwd \
`
SHELLMETAS = $saved
[dan] comments awk: `expr' is sure to be a smaller binary than awk
for procmail to fork, and it needs much less command-line code to
do this job. Note also that one still has to diddle with SHELLMETAS
to avoid a shell, because the awk code contains brackets; thus it
doesn't replace all.
There is also a way to remove words from the end of string by
procmail means if the strings are separated by same separator. Let's
use the word this-mailing-list-request which we would like to shorten
to this-mailing-list. [david] presented the recipe 1998-06-16 in PM-L.
VAR = "this-mailing-list"
# 1) if there is match at the end ending to these words
# 2) Get everything up till last match and store it to MATCH
# 3) Read MATCH, but exclude last dash "-"
:0
* VAR ?? -(owner|request|help)^^
* VAR ?? ^^\/.*-
* MATCH ?? ^^\/.*[^-]
{
VAR = $MATCH
}
9.15 Strings: Procmail string manipulation example
[1998-06-23 PM-L walter] ... Now we get to apply these formulas
to strip the last character off a string. It gets a bit ugly for
special cases. I've deliberately chosen a worst-case scenario.
VAR = "Testing 012301230111"
RC_APPEND = $PMSRC/pm-myappend.rc
:0
* VAR ?? ()\/.$
{
TAIL = $MATCH # last character of VAR "1"
# Get the longest match that does not end in the TAIL character
:0
*$ VAR ?? ()\/.*[^$TAIL]
{
HEAD = $MATCH # now "Testing 012301230"
# if the last two or more characters in VAR are
# identical, they all get chopped, oops
:0
* -1^0
* 1^1 VAR ?? (.)
* -1^1 HEAD ?? (.)
{
dummy = "tooshort"
INCLUDERC = $RC_APPEND
}
}
}
result = $HEAD # "Testing 01230123011"
# ........................................ pm-myappend.rc
# LENGTH(HEAD) plus 1 SHOULD equal LENGTH(VAR). That is
# not the case when the last 2 (or more) ending
# characters are identical. in that case, call appendrc
# recursively to stick back an appropriate number of
# TAIL characters.
:0
* -1^0
* 1^1 VAR ?? (.)
* -1^1 HEAD ?? (.)
{
HEAD = "$HEAD$TAIL"
INCLUDERC = $RC_APPEND
}
9.16 How to raise a flag if the message was filed
FILED = ! # ! is procmail "false"
:0 c: # We process the message more
* condition
foo
:0 a
{
FILED # Kill variable
}
...
:0 # Stop if previous cases filed the message
*$ $FILED
{
HOST = "_done_"
}
Or alternatively: procmail automatically sets `LASTFOLDER' if
it delivers message to mailbox.
LASTFOLDER # kill variable
:0 c:
* condition
foo
:0 c:
* condition
bar
... et cetera ...
:0
* ! LASTFOLDER ?? ^^^^ # Or ${LASTFOLDER+!}!
{
HOST = "_done_" # Force procmail to stop
}
9.17 Dollar sign in condition lines.
#todo, check this recipe
This doesn't seem to work for me...
* ^TO()$\foo@bar.com
[david] An unescaped dollar sign later in the line represents a
newline, so what you have there is searching for the following:
. An expression that matches the expansion of the ^TO token (which
is anchored to the start of a line by its definition), followed
by
. A newline, followed at the start of the next line by
. "foo@bar" [the backslash escapes the f, which didn't need
escaping], followed by
. any character that is not a newline (the period is unescaped),
and finally
. "com".
Try this instead:
*$ ^TO()$\foo@bar\.com
#todo: the dollar seems exactly the same in the above two
#todo Examples: are you sure that this is correct?
In fact, to avoid matches to things like foo@bar.community.edu,
you might want to do it this way:
*$ ^TO()$\foo@bar\.com\>
9.18 Finding mysterious foo variable
I have my fellow worker's procmail code and he uses a variable FOO
that I can't find in his code anywhere. It's not a shell variable
either, because it's literal. Where does it come from?
Your procmail runs /etc/procmailrc when it starts, please check
that. It may define some common variables already for all users.
9.19 Storing code to variable
One way to run complex code in a procmail recipe is first to store
it in a variable. Idea by [era]. You could do this in a separate shell
script too. The following example reads URLs from the body of
a message: the URLs have been put to separate lines and some special
Subject is used to trigger the dumping of the html pages:
# Code by [era]
#
COMMAND='while read url; do
case "$url" in
*://*)
lynx -traversal -realm -crawl -number_links "$url" |
$SENDMAIL $LOGNAME
;;
esac
done'
# Notice the trailing semicolon after `eval' !
:0 bw
* ^Subject: xxxxx
| eval "$COMMAND" ;
If you want to run the code inside the nested block, then look
carefully, there are double quotes around the command in backticks.
If you leave double quotes out, then each word in SH_CMD would be
interpreted separately:
$SH_CMD = '$echo "$VAR" >> $HOME/test.tmp'
:0
* condition
{
# condition satisfied; run the given shell command
# and do something more.
dummy = `"$SH_CMD"`
..rest of the code..
}
A similar construct works for message echo-ing too:
MESSAGE='Thank you so much for your message.
Unfortunately, the volume of mail I receive .... (blah blah blah).
If your matter is urgent, try calling +358-50-524-0965.
'
:0 hw
* ! ^X-Loop: moo$
| ($FORMAIL -rt -A "$MY_XLOOP"; echo "$MESSAGE") | $SENDMAIL
9.20 Getting headers into a variable.
[david] Here are several ways to get the entire header into a variable:
HEADER = `$FORMAIL -X ""` # The space after the X is vital.
HEADER = `sed /^$/q` # also writable as HEADER=`sed /./!q`
:0 h
HEADER=|cat -
will save the entire header into one variable. It has to be smaller
than $BUFSIZE, though. This way might work as well, and will require no
outside processes if it does:
:0
* ^^\/(.+$)*$
{
HEADER = $MATCH
}
9.21 Converting value to lowercase
If you know that a word belongs to set of choices, you can do
this inside procmail
LIST = ":word1:word2:word3:word4" # Colon to separate words
WORD = "WORD1"
:0
*$ LIST ?? :\/$WORD
{
WORD = $MATCH
}
But if you don't know the word or string beforehand, then this is
the generalized way: [idea by era and david]
:0 D
* WORD ?? [A-Z]
{
WORD = `echo "$MATCH" | tr A-Z a-z`
}
10.0 Suggestions and miscellaneous
10.1 Speeding up procmail
o Use absolute paths to take the burden of searching binary along path
from shell: Use $FORMAIL variable abstraction.
$FORMAIL = "/usr/local/bin/formail"
:0 fhw
| $FORMAIL -I "X-My-Header: value"
o Multiple `echo' commands that spread many lines can be converted
to single echo command if \n escape is supported. You usually
see these in autoresponders
echo "........."; \
echo "........."; \
echo ".........";
-->
echo ".........\n" \
".........\n" \
".........\n";
o You can avoid multiple and possible expensive FROM_DAEMON tests
by caching the result at the top of your .procmailrc. You can
now use variable $from_daemon like the big brother FROM_DAEMON.
The same idea can be applied to FROM_MAILER regexp. If you have
*pm-javar.rc*, it already defines variables `$from_daemon' and
`from_mailer' exactly like here:
from_daemon = "!"
:0
* ^FROM_DAEMON
{
from_daemon = "!!" # double !! means "OK"
}
:0
*$ ! $from_daemon
{
..do-it..
}
o Count the backticks and you know how many shell calls procmail
has to launch. See if you can minimize them and use some procmail
code instead.
o ^TO and other macros are expensive, see if you can use simple
Header:.*\ instead. Well, it's not clear if this
gives you much speed advantage.
o Don't call "$FORMAIL -xHeader:" every time you need a header
value, consider if it suffices to use `match' operator \/.
o You can minimize the calls to only one `formail' if you add many
headers along the way: See formail usage tips in this document
o Searching body is expensive, simply because it contains more text.
There isn't much to do about this, because you use `B' anyway
when you need it.
o See if you can move some tasks to your .cron file. procmailrc is
not meant for those purposes. Instead of calculation daily
values every time in procmail, let cron do that at 04:00 or
21:00. Don't run cron at midnight if you can, because everybody
else is running their crons at the same time. If "logical" date
change time can be used (when you arrive to work, when you
leave the work), use it in cron jobs.
o [philip] Setting `LINEBUF' permanently to a big value slows
procmail down.
o Remove all calls to `perl' and use programs that are nicer to
the system (If you just call command line perl, there is
probably an equivalent alternative with `awk' `tr' `sed' `cut')
o Examine each shell command and see if you do need `SHELLMETAS.'
If you can set `SHELLMETAS' to empty, this saves calling "sh" for
each invocation of the external command.
10.2 See the procmail installation's examples
Did you remember to look at the examples that come with procmail? If
not, it's time to give them a chance to educate you. Here is one
possible directory you could take a look. Ask from your sysadm if you
can't find the directory where to look into.
% ls /usr/local/lib/procmail-3.11pre7/examples/
Or if you're really anxious to get on your own, try this. The directory
/opt/local is for HP-UX 10 machines and the *forward* contains example
how to define your `.forward' for procmail.
% find /opt/local/ -name "forward" -print
If the find succeeded and found the file, then you know where the
procmail files installation directory is.
10.3 Printing statistics of your incoming mail
If you keep the procmail log crunching, it will record to which
folder the messages was filed. There is program `mailstat' which
can process the procmail.log file and print nice summary out of it.
If you generate the summary at midnight and clear the log, you
get pretty nice per day/per folder traffic analysis.
# -m merges all error messages into a single line
% mailstat -km procmail.log
10.4 Storing UBE mailboxes outside of quota
I want to store spam outside disk space. Problem: if I tell
procmail to deliver to, say, /tmp/spam.box, it does so just fine
(according to the log). Unfortunately, it delivers to /tmp on the
mail host which I cannot access. spam.box doesn't appear in the
/tmp directory of the shell machine when procmail is invoked for
incoming mail.
[philip] Under the most likely configuration of sendmail in
this situation, it is impossible to have procmail invoked by
sendmail on the shell machine: sendmail is probably set to just
forward all mail to the designated mail delivery machine.
There are other options: you could temporarily store the mail in
your account, then have a cronjob on the shell machine that
reprocesses the message. That would probably be more efficient than
having each message trigger an rsh to the shell machine. If you
actually get enough spam that it's pushing against your quota, then
the rsh is too expensive -- use a cronjob that invokes something
like:
cd your-maildir &&
lockfile spam.lock &&
test -s spam &&
{
cat spam >> /tmp/spam.box && rm -f spam spam.lock || \
rm -f spam.lock;
}
WARNING: the above assumes the following:
o everything in your-maildir/spam is spam and belongs in
/tmp/spam.box
o no further filtering of the messages is necessary: they just need
to be moved (it actually treats everything in the
your-maildir/spam as a single message and uses procmail as a
reliable copy command, thus the `DEFAULT' assignment as the use
of /dev/null as a empty procmailrc)
o /tmp/spam.box is a not a directory
If the latter two of those conditions isn't true OR IF THEY MIGHT
CHANGE then you should use `formail' `-s' to break the message apart
and invoke procmail on each one separately.
[era] Many sites cross-mount directories for various reasons. /tmp
is always local but /var/tmp might be cross-mounted between the
login host and the mail host; another one to try is /scratch -- and
if all else fails, ask your admin to set up an NFS share for this
purpose.
10.5 Using first 5-30 lines from the message
[era] The regex to grab few lines (or all of them, if there are
less than fifty) is not going to be very pretty, but it saves launching
an extra process.
:0 B
* $ ^^$SPCNL*\/$NSPC.*$(.*$)?(.*$)? ... etc, the rest of the lines
{
toplines = $MATCH
}
The skipping of whitespace at the beginning of the message is of
course not necessary. You should probably set `LINEBUF' reasonably
high if you grab many lines, say 30: 80*30 = 2400 bytes; probably
setting it to 8192 or 16384 is a good idea, depending how much you
want to match. The above gets ugly quickly, so
# But if N=30, sed ${N}q if you don't have head
:0 Bi
{
toplines = `head -$N`
}
:0 a
* toplines ?? pattern
{
...do-it
}
10.6 Using cat or echo in scripts?
I have seen a lot of examples that use 'echo', i.e.,
:0
* condition
| echo "first line of message" \
"second ..." \
"et cetera"
I started out with spam.rc from "ariel" which got me into the
habit of
:0
* condition
| cat file_containing_message
although I note that spam.rc did have one recipe using the echo
method. What are the reasons for choosing each method over the
other?
Here is a comparison table. Choose the one you think is best for you
o Echos don't have dependency on an external file:
everything is contained in the .procmailrc file. Echos keep
all the relevant stuff in one file. Cat's make you
maintain multiple files. That's the main
reason I lean toward echo's; you may have accounts on
several machines. It is easier to be able to copy just one
generic .procmailrc between them without having to copy a bunch
of messages also. Mostly, though, there's no real difference
between the two methods.
o Echo is easier to use with variables.
o Echo starts many processes, cat only starts one, but this is
not always true: In most current Bourne shell implementations,
echo is a builtin. This holds true with tcsh too.
o The main problem I see with the use of cat is "what happens when
you forget the file or destroy it ?". I suggest to, at least,
test that the file is readable before catting it.
o [richard] An argument against echo is that it is not well
standardized, and different versions may exist on the same
machine. Some recognize -n, some don't; some recognize embedded
metacharacters, some don't.This is an argument in favor of
`print'. Print, however, is not a built-in on all systems. The
comment on built-ins is pertinent to situations when a shell is
spawned. When procmail handles the call directly, it will
always look for a stand-alone executable. I guess echo may be
better, as long as we are aware of any differences in behavior
between built-in and stand-alone versions.
10.7 How to run an extra shell command as a side effect?
[jari] I was once wondering what would be the wisest way to send
messages to my daily "biff" log file about the events that
happened during my .procmailrc execution. This is how [david]
commented on my ideas
# case 1: print to BiffLog
dummy = `echo "message: $FROM $SUBJECT" >> $biff `
[david] Problems you get no locking on the destination file, and
unless you put it inside braces you have to run it on every message
unconditionally. (Also procmail tries to feed the whole message to
a command that won't read it, but the remedies for that don't help
very much.)
# case 2: We consume delivering recipe and therefor have to use
# `c' flag.
:0 whic:
| echo "message: $FROM $SUBJECT" >> $biff
Here it locks the destination file and you can add conditions to
it, so it's probably the best. If the head or the body is less than
one bufferful, you can limit the unnecessarily written data with `h'
or `b', but I think that in most OSes a partial buffer and a full
one are the same amount of effort.
# case 3: We use side effect of "?" here. Cool, but this
# doesn't do $biff file locking thus message order may
# not be what you expect.
:0
* condition
* ? echo message: $FROM $SUBJECT >> $biff
{ } # procmail no-op
We have conditions possible, but there is no locking on the
destination file. I'd go with method #2 or a variation thereof:
:0 hic: # we don't necessarily need `w'
* condition
| echo message: $FROM $SUBJECT >> $biff
:0 hi: # Or you could use this
* condition
dummy=| echo message: $FROM $SUBJECT >> $biff
[jari] Now, when [david] has explained how various ways differ
from each other, I present the recipe where I used the case 3.
When I was dropping a message to a folder, I wanted to send a
message to my biff log too. The idea is that the drop-conditions
have already matched and then we run extra command by using side
effect of "?" token. As far as the recipe is concerned, the "?"
is a no-op. The pedantic way would have been to add the LOCKFILE
around to the recipe, but imagine 50 similar recipes like
this...and you understand why the LOCKFILE was left out. It's
only necessary if you worry about sequential writing to the biff
file.
:0 :
* drop-condition
* ? echo message: $FROM $SUBJECT >> $biff
$MBOX
10.8 Forcing "ok" return status from shell script
...the "?" trick only allows running some additional shell
commands (`true' command always succeeds) while conditions
above have already determined that drop will take place. And you
can always make condition to succeed if a misbehaving shell script
always returns a failure exit code.
* ? misbehaving-shell-script || true
[david] If the script *always* returns a failure code, just do this:
* ! ? misbehaving-shell-script
The more complex case is a script that can return either success or
failure but you don't care which; if the drop conditions passed,
you want to run the action line. `echo' can also fail if the
process lacks permission or opportunity to write to stdout. A more
reliable choice is true(1); its purpose in life is to do nothing
but exit with status 0.
The command `:' is a shell builtin which always returns true
status. Not exactly more readable than true(1) "|| :" will save the
invocation of true (unless true is built into $SHELL), but procmail
will still run a shell. On the other hand, as long as the command
itself has no characters from `SHELLMETAS' a weight of 1^1 and no
"|| anything" will avoid the shell process as well.
However, there is yet a better way to make sure that a failure by the
script doesn't make procmail abort the recipe:
:0 flags
* other conditions
* 1^1 ? shell-script
action
Regardless of the exit status of the script, the condition will score
1 and not interfere with procmail's decision about the action line of
the recipe. Weighted exit code conditions behave like this (see the
procmailsc(5) man page):
* w^x ? command
scores w on success or x on failure.
* w^x ! ? command
scores the same as this:
* w^x pattern_that_appears_in_the_search_area_$?_times
10.9 Make your own .procmailrc available to others
There is never too much to learn about procmail and the best source
is the rc files that people have done. Remember to comment
your .procmailrc file well before you put it available. Below
is a recipe
for sending your .procmailrc upon request. If you want to send
anything more that one or two files (many times you want to put
other files available too), then please do not use this code but a
general file server module.
(Note: #REF #procmail_module_list ;Procmail module list;)
:0
* ! ^Subject:.Re:
* ^Subject:.*send.*procmailrc
* ! ^FROM_DAEMON
{
:0 fhw:
| $FORMAIL -rt \
-A "Precedence: junk" \
-I "Subject: Requested .procmailrc"; \
-I "$MY_XLOOP"
:0 a hwic
| ( cat - $HOME/.procmailrc ) | $SENDMAIL
:0 # trash the "Send procmailrc" request
/dev/null
}
10.10 Using dates efficiently
_Note_: See module list, where you will find `date' and `time'
parsing modules. You can also parse the date from the first
`Received' or `From_' header if it is the same each time in your
system. That would be orders of magnitude faster and decreases
your system load if you receive lot of mail.
Calling `date' in your procmail script _many_ times is not a good
idea. Use the `MATCH' as much as possible to be efficient in
procmail, like below where we call `date' only once. If you are not
in the same time zone as your server, and you want an accurate
report of the date, you might amend the invocation to the following:
date = `TZ="KDT9:30KST10:00,64/5:00,303/20:00";date "+%Y %m %d"`
The basic recipe is here
# By [richard] add %H:%M%S if you want these as well
:0
* date ?? ^^()\/....
{
YYYY = $MATCH
}
:0
* date ?? ^^..\/..
{
YY = $MATCH
}
:0
* date ?? ^^.....\/..
{
MM = $MATCH
}
:0
* date ?? ()\/..^^
{
DD = $MATCH
}
TODAY = "$YYYY-$MM-$DD" # ISO std date: like 1997-12-01
10.11 Keep simple header log
Here is a simple strategy: Record all what comes in and record all what
happened to that message. See how brief info is constantly recorded to
*BIFF* folder. You can now check the *BIFF* log every day to
see if the messages were sunk to right folders: Remember to add *BIFF*
rule to every recipe, so that the sink message [sunk-somewhere] is
recorded after incoming message headers.
I use this one-liner log in my Emacs window which is updated by
`live-mode' process all the time (See the Emacs tools section
later). It gives a nice overview of email messages the I'm receiving:
it's my biff(1) equivalent in Emacs.
# this requires that HH and MM have been setup before,
# see pm-jadate.rc
NOW = "$HH:$MM" # the time only
TODAY = "$YY-$MM-$DD $NOW" # ISO 8601: date and time
$NULL = $SPOOL/junk.null.spool # /dev/null is dangerous
BIFF = $PMSRC/pm-biff.log
# or if you prefer a log per day (easy for cleanup):
# BIFF = $PMSRC/pm-biff.log.$YYYY$MM$DD
# .............................................. headers ...
# DON'T USE THESE: they call shell
#
# FROM = `$FORMAIL -zxFrom:`
# SUBJECT = `$FORMAIL -zxSubject:`
:0 # Use procmail match feature
* ^From:\/.*
{
FROM = "$MATCH"
}
:0 # Use procmail match feature
* ^Subject:\/.*
{
SUBJECT = "$MATCH"
}
# ............................................. incoming ...
# record log of incoming mail
# or if you use a biff file per day, you could have:
# echo "$NOW $FROM $SUBJ" >> $BIFF
:0 hwic:
| echo "$TODAY $FROM $SUBJ" >> $BIFF
# ......................................... null recipe ...
# spam-like addresses - let friends@planetall.com fall through
:0 :
* From:.*(remove|delete|free|friend@)
* ? echo " [null-AddrReject]" >> $BIFF
$NULL
10.12 Gzipping messages
[Sean B. Straw ] On the recipe
delivery line where you'd normally be tossing it into a folder do
this instead:
:0 c:
|gzip -9fc >> $MAILDIR/mail.mbox.gz
This will compress each message as it comes in (and since most are
TEXT, it does a fine job - MIME, OTOH is one of the best ways to
mailbomb someone since it doesn't compress well - but the indirect
bombing via mailing lists doesn't do this), reducing the disk space
required, usually dramatically. Done in conjunction with something
like the following at the end of your .procmailrc, you could have a
header file you could quickly rummage through looking for valid
messages to add to a procmail recipe, then run:
gzip -d -c mail.mbox.gz | formail -s procmail -m recipe.rc
(note that if the recipe delivers into the mail.mbox.gz file on any
condition, then you should look to MOVE the file before running
this process, and use the moved version. In fact, this would be a
good idea anyway, as newly delivered mail may appear in the end of
the gzip file while you're doing this - and since your ultimate
goal is to be able to eliminate junk, you'll want to know that
after you've processed a gzipped mail file, you can delete it
without accidentally whacking new mail).
:0
* LASTFOLDER ?? ^^^^
{
# Save the message in case we need to retrieve it.
:0 c:
|gzip -9fc >> $MAILDIR/mail.mbox.gz
# copy headers for easy browsing - including being able to
# identify lists you're being subscribed to.
:0 h:
header.log
}
10.13 Emergency stop for your .procmailrc
[jari] If I have a bad luck while I am testing a new recipe, it may
run in a loop and and it may send me continuously email messages. I
then have to quickly recall .procmailrc and start disabling my
individual "control" recipe files. Yet I figure, in situations like
this where every second is important, there must be a better way.
[alan] This is quite easy already; put this at the top of your
.procmailrc:
# instead of leading dotfile, you may prefer
# stopFile = $HOME/procmailrc.stop which shows up in default ls.
# In the other hand you can do ls ~/.procmail* to see both...
stopFile = $HOME/.procmailrc.stop
:0
*$ $IS_EXIST $stopFile
{
EXITCODE = $EX_TEMPFAIL # Means: retry later; requeue
HOST = "_stopped_by_external_request_"
}
Then, when testing your procmailrc and disaster happens, you can
simply do following to disable your procmailrc filtering.
% touch $HOME/.procmailrc.stop
[richard] This is also a candidate recipe for including in
an INCLUDERC. Combining the two ideas, we have a file
procmailrc.stop which contains the recipe and is included near the
top of .procmailrc, When you don't want it, mv it to procmailrc.go.
Procmail complains about missing INCLUDERCs, but it does not
complain about them if they exist and are empty. Another reason to
not use dotted file names, but to use cp instead of mv.
11.0 Scoring
11.1 Using scores by an example
First make all the needed matches and let the `SCORE' value to be
set. Examine the score after the final value has been calculated.
The condition lines say:
o Start with some threshold: -250.
o Read the subject into `MATCH'
o Add 50 for each match of !. Notice the "^1": if it read
"^0", only one 50 would be added for "!!!!", now that counts
as 4 x 50 = 200. See procmailsc(1) for "^N" syntax.
o Any dollar sign is likely spam.
o find uninteresting subject words
o And a negative count for replies.
o Usually spam doesn't seem to have Re: in subject field.
(but don't rely on this, spammers have started to use "re:")
o letters such as !!! frequently found in the body are usually
indication of spam. Add 100 for each match.
# Idea by 26 Sep 97 Stephane Bortzmeyer
:0
* -250 ^0
* ^Subject:\/.+$
* 50 ^1 MATCH ?? [!]
* 50 ^1 MATCH ?? [$]
* 100 ^1 MATCH ?? ()\<(free|sex|opportunity|money|great)\>
* -250 ^0 ^Subject: *(Fwd|Fw|re):
* B ?? 100 ^0 ()!!!
{ } # official procmail no-op
SCORE = $= # Score has been calculated
:0 fhw
| $FORMAIL -i "X-Spam-Score: scored $SCORE"
:0: # If score had positive value, sink message
*$ $SCORE^0
junk.spam.mbox
Given the following subject:
"Great opportunity for free sex; no money required!!!!"
procmail scores it this way: ! was found 4 times (200/weight 50),
"free|sex..." regexp matched 4 times (400/weight 100).
condition score Total sum so far
---- ----------------
procmail: Score: -250 -250 ""
procmail: Score: 200 -50 "[!]"
procmail: Score: 0 -50 "[$]"
procmail: Score: 400 350 "^Subject:.*\"
procmail: Score: 0 350 "^Subject: *(Fwd|Fw|re):"
procmail: Score: 0 350 ! ""
procmail: Assigning "SCORE=350"
[david] Some notes on possible regexps and their differences:
* 100^1 ^Subject:.*\<(free|sex|opportunity|money|great)\>
That condition says to score 100 for every subject line that
contains any of those five words ... not to score 100 for every one
of those words in the subject, but 100 for every subject line that
contains any of those words. So it will never score more than 100
unless there are multiple subject lines. You see, it offers five
alternative regexps:
^Subject:.*\
^Subject:.*\
^Subject:.*\
^Subject:.*\
^Subject:.*\
Offhand, I think regexp below would score 400: 100 for
"Subject.*free" and 100 for "sex" etc. Of course, the score might
be higher if other lines in the header included the strings "sex",
"opportunity", "money", or "great", but appearances of
"free" outside the subject wouldn't be counted.
* 100^1 ^Subject:.*\
[translates to]
^Subject:.*\
And this one would score 400 too. How? `MATCH' would contain whole
subject and there would be non-overlapping matches to " great ", "
opportunity ", and " free ". If we got rid of either or both of the
word-border marks, it would score 500.
Subject: Great opportunity for free sex; no money required!!!!
* 100^1 MATCH ?? ()\<(free|sex|money|opportunity|great)\>
11.2 Brief Score tutorial
#todo: test
[elijah] If you're serious about using scores, please spend
a minute reading this short example.
VERBOSE = "yes"
:0
* 1^1 foo
* -2^2 bar
{ }
a = $=
:0
* 1^1 foo
* -2^2 bar
{
:0 f
| echo Whee: fun ; cat -
}
b = $=
:0
* 1^1 foo
* -2^2 bar
{
whee = "fun"
}
c = $=
:0 h
/dev/null
Then if you would send a message
From foo Fooof
To: bar
Subject foobar
body-something-here
The log file will tell you what happened.
procmail: [20175] Fri Sep 26 10:25:23 1997
procmail: Score: 3 3 "foo"
procmail: Score: -6 -3 "bar"
procmail: Assigning "a=-3"
procmail: Score: 3 3 "foo"
procmail: Score: -6 -3 "bar"
procmail: Assigning "b=0"
procmail: Score: 3 3 "foo"
procmail: Score: -6 -3 "bar"
procmail: Assigning "c=-3"
procmail: Assigning "LASTFOLDER=/dev/null"
procmail: Opening "/dev/null"
From foo Fooof
Folder: /dev/null 46
11.3 Score's scope
If you have a delivering recipe and the score is positive, the
action lines are executed. If the score is less or equal to 0, then
the `$=' information is lost, but also at the next recipe
definition, even if the recipe is never executed. Study following
example:
:0
* 10^0
{
dummy = "Score for condition xxxx was: $= $NL"
:0
{
dummy = "Next recipe, Score no longer available: $= $NL"
}
}
# Wont' work. $= is getting set back to 0 outside of
# the delivering recipe.
dummy = "Score outside of all recipes: $= $NL"
Here is interesting anomaly which [richard] discovered. It is
presented here only as a curiosity. DO NOT USE IT IN YOUR RECIPES.
(this not "clean programming", but a hack)
[david] If you want to save the score for later use (even if it is
zero or negative):
:0
* 10^0
{ } # procmail no-op
SCORE = $=
:0 A
action_if_positive
If other recipes that clobber the references for the `A' flag
intervene, this will work:
:0
* 10^0
{ } # procmail no-op
SCORE = $=
... more stuff ...
:0
*$ $SCORE^0
action_if_positive
11.4 Counting length of a string
Supposing `VAR' contains some text, we can count the characters
by using dot to match every character and increasing score for
every match.
:0
* 1^1 VAR ?? .
{ }
LENGTH = $=
11.5 Counting lines in a message (Adding Lines: header)
[1995-10-03 PM-L Idea by David Karr ] [david]
later corrected 1998-01-02: For one thing, the second condition
always counts one too many (the final newline plus the closing
putative newline create the extra match); second, after making that
correction, an empty body would score zero and leave the variable
undefined.
:0
* 1^1 .
* 1^1 ^.*$
* -1^0
{ }
lines = $=
:0 fhw
* ! ^Lines:
| $FORMAIL -a "Lines: $lines"
The reason we used it at all was that size conditions worked only on
the entire text regardless of H or B or HB flags at the top of the
recipe. Nowadays we can do this and get the accurate figure in one
condition:
# leave `B ??' out to measure the entire message
:0
* 1^1 B ?? > 1
{ }
size = $=
If you want to be silly about it (as some of us very often do),
:0
* -1^1 B ?? > -1
{ }
size = $=
gives the same result, and as long as the search area is non-empty,
so do these, which are even sillier:
:0
* 1^-1 B ?? < 1
{ }
size = $=
:0
* -1^-1 B ?? < -1
{ }
size = $=
[Karr] This recipe counts bytes in the message, you could use this
Content-length replacement, prefer using the next recipe. The first
score counts every character, and the second score sums up every
line (that is: newlines are added).
:0 HB # use B to measure body only
* 1^1 .
* 1^1 ^.*$
{
textsize = $=
:0 fhw
* ! ^Content-length:
| $FORMAIL -a "Content-length: $textsize"
}
11.6 Determining if body is longer than header
:0
* 1^1 B ?? > 1
* -1^1 H ?? > 1
{
..body was longer
}
11.7 Matching last Received header
[david] Here is way to use scores to hit the bottommost `Received'
header.
:0
* $ 1^1 ^Received:.*by$s+\/.*
action
11.8 How to add Content-Length header
We use procmail for local delivery, and would like to get it
to generate the content-length header, if one doesn't exist. SUN-OS
mailtool at least gets confused and merges messages together if
there is no message body.
[stephen] All you need to do is: a) Make sure that procmail is started
without the -Y flag. b) Either, in your sendmail.cf, insert:
H?l?Content-Length: 0000000000
Or (slightly less efficient), insert the following recipe in your
/etc/procmailrc file and Procmail will take care of any necessary
magic.
:0 hfw
* !^Content-Length:
| /usr/bin/formail -a "Content-Length: 0000000000"
11.9 Testing message size or number of lines
Size conditions ignore `H' and `B' on the flag line and always work on
`HB' unless another search area is specified on the condition's own
line. To test *only* the body,
:0 # Note: this is in BYTES
* $ B ?? < $NBR
{
...whatever when fewer bytes
}
This syntax would obey a B flag on the flag line:
:0 B # Note: this is in LINES
* -1^1 .
* -1^1 ^.*$
*$ $NBR^0
{
...whatever when fewer lines
}
11.10 Counting commas with recursive includerc
[jari] Foreword: David and Phil really are experts with procmail,
and let this section serve as an example to "what on Earth is
recursive procmailrc and how it is used?". I would not personally
use recursive includerc, simply because I would not trade clarity:
I find this easier to understand and maintain. `split' just
explodes input according to comma and the `print' return how many
elements were exploded to array `a'. The performance hit is not
bigger than forked `procmail' binaries in recursive version.
:0
* ^CC:\/.*
{
field = $MATCH
saved = $SHELLMETAS
SHELLMETAS
commaCount = `echo $field | awk '{print split($0,a,",")}' `
SHELLMETAS = $saved
}
See the recursive RC implementation at
[richard] Here is recipe that needs no recursion. MAX_RECIP
is set to 9, but you may prefer some other value. This counts each
comma. It allowed in addresses.Some folks sum Resent-xx *or*
non-Resent-xx headers. I sum all.
:0
* 1^1 ^(resent|apparently-)?(to|b?cc):\/.*
* 1^1 MATCH ??,
* $ -$MAX_RECIP^0
{
:0
* $ $=^0
* $ $MAX_RECIP^0
{
RESULT = "Count of commas is $="
}
}
12.0 Formail usage
12.1 Fetching fields with formail -x
If you're new to procmail your first though to read a header
content from the message would might be call:
SUBJECT = `$FORMAIL -xSubject:`
That's not good. DON'T Do THAT. You just created expensive shell
subprocess where procmail calls `formail' and feeds full message to
it. We can do the same with minimum efforts:
:0
* ^Subject:\/.*
{
SUBJECT = $MATCH
}
No shell subprocess called. This is 10x faster and consumes fewer
resources, while it may need more typing. Use it and your your sysadm
is happy with your well behaving procmail recipes that don't load
the CPU unnecessarily. There are cases where you need to launch
`formail', eg let's derive the address of the sender and store it
to variable:
FROM = `$FORMAIL -rtzxTo:`
But you can still make this more efficient. Here is one example where
you actually want to use "old" `=|' style variable assignment,
make sure there are _no_ extra spaces:
:0 hw
FROM=|$FORMAIL -rtzxTo:
That way only the _header_ gets fed into formail, whereas the
previous backtick fed the _whole_ message. Also, you can then check
the return code of formail with `a' or `A' recipe after this one.
12.2 Always use formail's -rt switch
[faq] `-r' breaks RFC822, so always use `-rt' if you don't know
what this means. Perhaps you should always use it anyway.
[david] There is formail -r[t] rank bar graph in the source code of
3.11pre4. It might be easier to follow as a top-to-bottom listing
(and again, Tom Zeltwanger appears to be using one of the older
versions where From_ was mistakenly overpromoted). These are the
rankings in version 3.11pre4:
formail -r: formail -rt:
Resent-Reply-To: Resent-Reply-To:
Resent-Sender: Resent-From:
Resent-From: Resent-Sender:
Return-Receipt-To: Reply-To:
Errors-To: From:
Reply-To: Sender:
Sender: Return-Receipt-To:
From_ Errors-To:
Return-Path: Return-Path:
Path: From_
From: Path:
[Stephane Bortzmeyer ] Always use `-rt' and
never `-r'. Because such precedence (Sender over From) is an
important violation of RFC 822. There is one canonical order,
described in the RFC and nothing else should be used, like fuzzy
ranking or, worse, reordering. This is a serious problem with
formail.
The proper order is:
Reply-To, else From, else Sender, else
And, how would you deal with resent mail?? Ie: Resent-Reply-To,
Resent-From, and Resent-Sender?
It treats `Resent-X' as X (" Whenever the string `Resent-' begins a
field name, the field has the same semantics as a field whose name
does not have the prefix. "). So you have to choose an order between
them, the RFC does not specify it.
[david] I think that the idea is that `-r' is intended to determine
the origination address, not the place to reply; `-rt' is for
determining the place to send replies. For addressing a response,
yes, `-rt' will invert the header in a way more in line with the
rules; for figuring out the origination point,
formail -r -zxTo:
might be better than
formail -rt -zxTo:
And here's an additional problem: `formail' `-rD' always uses the
`-r' precedences; you can't make it use the `-rt' precedences
and the `-D' cache checking function at the same time.
4.4.4. AUTOMATIC USE OF FROM / SENDER / REPLY-TO (RFC 822 excerpt)
For systems which automatically generate address lists for
replies to messages, the following recommendations are made:
o The `Sender' field mailbox should be sent notices of
any problems in transport or delivery of the original
messages. If there is no `Sender' field, then the
`From' field mailbox should be used.
o The `Sender' field mailbox should NEVER be used
automatically, in a recipient's reply message.
o If the `Reply-To' field exists, then the reply should
go to the addresses indicated in that field and not to
the address(es) indicated in the `From' field.
o If there is a "From" field, but no `Reply-To' field,
the reply should be sent to the address(es) indicated
in the `From' field.
Sometimes, a recipient may actually wish to communicate with the
person that initiated the message transfer. In such cases, it is
reasonable to use the `Sender' address.
This recommendation is intended only for automated use of
originator-fields and is not intended to suggest that replies may
not also be sent to other recipients of messages. It is up to the
respective mail-handling programs to decide what additional
facilities will be provided.
12.3 Using -rt and rewriting the From address
Sendmail adds the `From' header which points to your account. But in
some cases you may wish to rewrite the `From'.
o You respond to spammer and you want to hide in some extents your
address. ( The headers will still be there, but at least
hitting `r' in most MUA's pick up the `From' )
o You want to rewrite `From' to show your virtual address
me@forever-lasting-address.com instead.
o You are in some other account currently, but you want to send
message to some Net service (eg. Mailing list) that expects to
see the same address you first time used in subscription.
You could also use `Reply-To' to signify where you want further
responses to go, but that doesn't hide your true `From' address. And
there are still MUAs that don't obey `Reply-to'. Whatever reason
you have to rewrite From header, here is the command.
:0 fhw
| $FORMAIL -rt -I "From: me@forever-lasting-address.com"
12.4 Formail -rt and Resent-From header
Here is something that made me scratch my head a lot. Let's examine
scenario first which explains how the email travels.
account --> virtual-address --> Local-address
In this chain I was sending message from my University account to
my official work address, the *virtual-address* delivers
the mail to right local domain. There is only one problem with this
picture. When I generated response from *Local-address* with
`formail' `-rt', the generated address pointed back to
*virtual-address, which pointed back to *Local-address* of
course. A loopback was ready, I never got route travelling to
original address *account*
What was happening here was that the mailserver that handled the
virtual-address, didn't *forward* the message, but instead
*resent* the message. In this process a set of new headers were
generated:
Resent-From:
X-From-Line:
Received: from
Resent-Message-Id: <199710151903.WAA28670@virtual-address>
Resent-Date:
Resent-To:
Received: ...
Message-Id: <199710151904.WAA05050@account-domain>
From:
And now when the formail -rt command was used, it picked up the
`Resent-From' added destination where the message should be returned.
Surprising, but according to procmail, 100% correct. `Resent-From'
has higher priority than `From'.
The Resent-* headers are considered *informative*, and should never
be used when automatically generating a response. The problem here
is the middleman, it should not _resend_ a message, but rather
_forward_ it. So I put this into my .procmail to handle the broken
middleman in our site.
# Remove that misleading Resent-From if it was added by our
# "middleman"
:0 fhw
* Resent-From:
| $FORMAIL -IResent-From:
[edward] adds to this that: As you know, `formail' `-rt' is
for composing a response to the address from which an e-mail was
sent. Let's say you are on vacation and have set up a procmail
recipe to autorespond to all e-mail you receive. Furthermore, let's
say Joe sends me an e-mail and I re-send it to you. If you wanted
to respond to the sender of the e-mail that you received, would you
e-mail me or Joe? You better e-mail me because I was the one who
sent it to you. Joe may not even know you. Imagine if you did send
your response to Joe. It would probably cause him considerable
confusion as to why you are sending him e-mail informing him that
you are vacation.
formail `-rt' uses a heuristic algorithm to determine who it should
respond to, based on the presence of various headers and their
contents. If you look at the formail.c source code, you'll see a
graphical representation of this algorithm. It will also explain
difference between the results of `-r' and `-rt'.
`Resent-Reply-To' has the highest relative importance/reliability of
all header fields. Next is Resent-From and Resent-Sender, followed
by Reply-To, From, Sender, et al.
12.5 Quoting the message
Use formail -rtk
12.6 Without quoting the message
Use formail -rkb or formail -rkt -p '' or formail -rkt -b
12.7 How to include headers and body to the reply message
[david] ...It does require that the entire head fit into sed's hold
space, but it almost always will; exceptions are cases where the
sender messed around and added a bunch of uninformative (and
usually self-congratulatory) additional headers or when the message
got caught in a loop for a while but finally escaped before being
bounced for too many hops.
:0 fhw r
| sed -e H -e '$ G'
:0 fhw
| $FORMAIL -rt; ... now generate reply ...
12.8 Adding text to the beginning of message
We don't actually filter anything here. It's just a trick to
reprint headers and add some text after them: text appears
at the beginning of body.
:0 fhw
| cat - ; echo "This text comes after the headers."
12.9 Adding text to the end of message
:0 fb
| cat -; echo "added text after body"
12.10 Adding text before quoted message
If you are generating an auto-reply message where you want to place
the notification to the beginning of body followed by the quoted
original message, here is recipe for it. Substitute *condition* to
trigger the reply condition.
:0
* condition
{
:0 fhb
| $FORMAIL -rtk -p '>' \
-I "From: me@here.com" \
-I "$MY_XLOOP"
:0 fhw
| cat -; echo "added message at the start of body"
}
12.10 How to truncate headers (save filing space)
[Idea by Rodger Anderson ] As a last
recipe, if you're tight of space, you could remove extraneous
headers. But make sure you want to that, because headers may
contain useful information about URLs and other things like mail
server addresses. Some people keep signature information in
separate X-header (say: `X-My-Info') instead of at bottom of
message so that it won't bother people and disturb reply quoting.
# Strip header to bare minimum
# If this is MIME multipart, then skip recipe
:0 fhw
* ! multipart
| $FORMAIL -k \
-X Date: \
-X Subject: \
-X Message-Id: \
-X From \
-X To: \
-X Cc: \
-X Reply-To: \
-X Mime-Version: \
-X Content-type:
:0 :
mail.default.mbox
[david] comments the final recipe
o You should keep the `Reply-To' header if there is one. If the
sender wanted replies directed to a different address than that
in the `From' header, you are losing that information and, when
you respond, writing to the wrong place.
o You ought to keep `To' and `Cc' so that you can tell when you read
your mail who else was sent it. If your mail user agent has a
groupreply or replyall function, keeping `To' and `Cc' will allow
that feature to continue working. This way you are cheating
yourself out of it.
o '-X From' is enough to keep both the `From_' line and the `From'
header. You don't need to specify -X From: again after it.
(To keep `From_' without `From:' you need to say -X "From " or
something similar, with a quoted space.)
o All mail is going to have a line (usually two) beginning
'From'.
Another slightly different approach is to kill the headers that
take the most of the space. If you're not interested in tracking
down the original sender of possible UBE message, then you can
remove the `Received' headers. You may want to fill out the
condition line to simplify only your work or campus messages,
and let other messages retain their full headers.
:0 fhw
* possible-condition-to-handle-only-certain-messages
| $FORMAIL -I Received:
12.11 Adding extra headers from file
[stephen] Notice that the obvious solution won't do here:
:0 fhw
* condition
| $FORMAIL -rt | cat - $HOME/newHeaders
The problem here is that there will be a newline in the middle, which
causes the header to be shortened (procmail determines the new
header/body boundary after having processed each filter). Use the
following instead.
:0 fhw
* condition
| $FORMAIL -rt -X "" ; cat $HOME/pm-newHeaders.txt ; echo
[david] If $HOME/newHeaders ends in a blank line, you don't
need the "; echo". Under some circumstances procmail puts back the
blank separating line if it gets lost, but I'm not sure exactly what
those are, and you have a SHELLMETAS character in there already (the
first semicolon), so a shell is forked anyway.
But this is my favourite way (it assumes that formail -r will never
generate a continuation line for From:); if you use it, make sure
that the newHeaders file does NOT contain a trailing blank line:
:0 fhw
* whatever
| $FORMAIL -rtn
:0 A fhw
| sed "/^From:/r $HOME/newHeaders"
12.12 Splitting digest
[Idea by David Hunt] One interesting idea to handle digests
automatically as single messages if that we call procmail
recursively. First Call formail to split the mail when headerfields
are contained in the body, calling procmail again as the
output-program of formail. insertion of X-Loop makes it possible to
reuse .procmailrc for the separate messages.
# If it looks like more than one mail, send to formail for
# splitting, then send back to procmail for sorting again.
:0 B
* ^From [-_+.@a-z0-9]+ (Sun|Mon|Tue|Wed|Thu|Fri|Sat)
* ^From:
* ^TO
*$ ! H ?? ^$MY_XLOOP
| $FORMAIL -A "$MY_XLOOP" -m4s procmail
12.13 Mailbox: Splitting to individual files
[david] To split some old email archives into individual
files while stripping unimportant header fields, use following. The
keys are to use procmail's `-p' option, to strong-quote `$FILENO' in
the setting of `DEFAULT', and to use /dev/null or a known empty file
as the rcfile.
% setenv FILENO 0000
% formail -kXDate: -XFrom: -XTo: -XSubject: -XIn-Reply-To: \
-XX-Mailer +1ds \
procmail -p DEFAULT=`pwd`/'$FILENO.txt' \
/dev/null < inputfile
12.14 Mailbox: Extracting all From addresses from mailbox
The -ns causes formail to split the mailbox and feed each mail
separately to next process.
% cat mailbox | formail -ns formail -xFrom: | sort -u
12.15 Mailbox: Applying procmail recipe on whole mailbox
% cat mailbox | formail -ns procmail pm-experiments.rc
12.16 Mailbox: run series of commands for each mail (split mailbox)
...Maybe the heat has melted my brain, but I can't seem to get
formail to perform a series of commands on each mail that it has
split from a folder. Here's an example of a simple debugging
attempt: I've tried parentheses, putting the commands into a
shell function, and other flailings too numerous to remember, all
to naught.
% formail -s addr=`formail -XFrom: | formail -r | formail -zx To`;\
echo "$addr" >>output
It appears that formail doesn't use the shell when executing the
command specified when splitting. No SHELLMETAS here. Given that, the
secret is to fire up the shell explicitly yourself to do the piping:
% formail -s sh -c 'formail -XFrom: | formail -rzxTo:' >> output
Note that you only need two formails in the pipe, not three, as the -r
flag works correctly when combined with other flags.
...To me, a large mailbox would consists of about 10,000 messages
per month (that's about what I get). That would mean that my
mailbox would contain 60,000 messages in 6 months. I sure as heck
wouldn't want to skim through it all or even try to load it up in
an MUA.
[1998-08-27 Bennett Todd ] I also deal with monster
volumes of email. I've switched over entirely to Maildir in all my
email handling; the only place I still see mboxes is in the save
folders of my netnews reading (using slrn) and whenever I want to
process them I either convert them into Maildir (e.g. for archival)
or simply split them into multiple messages. Splitting into
multiple messages turns out to be preposterously easy; using GNU
csplit:
[richard] The csplit invocation shown here will catch
occurences of ^From embedded in the message body if your MUA
hasn't escaped them with a >. Some MUAs use content-length
headers and don't escape ^From. Procmail supports this. Be cautious
if you choose to use this simple split.
csplit -n4 - '/^From /' '{*}'
That will create an empty xx0000 which I delete, and leave the
messages in files named xx0001, xx0002, etc. If you have more than
9999 messages in a folder then go -n6, or -n9, or whatever. Once
they're split it's really easy to use shell tools to bundle
messages into batches, file them into categories, etc.
If you are archiving all email traffic forever (which I do) then
another dandy tool to add to the mix is glimpse
http://glimpse.cs.arizona.edu/ it takes a while to build the index,
but that's a fine job to run out of cron at night. Once the index
is built it's a pleasingly quick way to root through big archives
of messages.
12.17 Option -D and cache
[Bob Weissman ] and [stephen] These files are
self-limiting. The number after the `-D' is the size in bytes above
which the older entries will be removed. E.g., my .procmailrc has
:0 Wh: .msgid.cache$LOCKEXT
|$FORMAIL -Y -D 12288 .msgid.cache
And the file never exceeds 12288 bytes by very much. Though
formail indeed exceeds this size by as much as the length of one
`message-ID', the file size should never grow significantly beyond
that, even if used indefinitely. The file is in binary format, each
entry terminated by single null byte, and an occasional (significant
placeholder) double null
[philip] The format of the cache is initially as follows:
entry\0entry\0entry\0\0
When the file size grows to equal-to or greater-than the size
specified on the command line, formail starts over at the
beginning, using a double-null to mark where it stopped. However,
entries after the double-null, except for the partially overwritten
one, are still valid and checked, so that the file is then in the
format:
entry\0entry\0entry\0\0partial-entry\0entry\0entry\0\0
New entries will be written after the first double-null, so that it
implements a circular cache. Check out lines 319-322 of formail.c
12.18 Option -D and message-id in the body
Some of my messages contain the original Message-ID in the body
of the letter and not the Header. Is there an option for Formail to
over come this problem?
[david] This is strictly untested; I don't know where in the
body the Message-ID's appear, but if they're at the top of the body,
this might help:
:0 hW # Message-Id: in the head,
*$ ^Message-Id:.*$NSPC
| $FORMAIL -D $cache_size $cache_name
:0 E BbW # If not but there's one the body, try body.
*$ ^Message-Id:.*$NSPC
| $FORMAIL -D $cache_size $cache_name
You might want to copy a `Message-Id' from the body to the head in
any case (if there's none already in the head) just to have it in
the right place, so we could do that first and then `formail' `-D'
will work normally. This form will run formail twice if the
`Message-Id' header is in the body instead of the head, but it will
look for `Message-Id' on *any* line of the body, not just at the
top:
:0 fhw
*$ ! H ?? ^Message-Id:.*$NSPC
*$ B ?? ^\/Message-Id:.*$NSPC
| $FORMAIL -A "$MATCH"
:0 hW
| $FORMAIL -D $cache_size $cache_name
12.19 Reducing formail calls (conditionally adding fields)
#todo: url
Suppose you want add fields to the message when some condition is met:
:0 # compose initial reply
| $FORMAIL -rt
:0
* condition1
| $FORMAIL -A "X-Header1: value1"
:0
* condition2
| $FORMAIL -A "X-Header2: value2"
Hm, we have three processes called here, can we minimize the calls?
Yes, this is idea from [philip] and [david]. Notice that there is
only ONE process needed.
:0
* condition1
{
hdr1 = "-AX-Header1:value"
}
:0
* condition2
{
hdr2 = "-AX-Header2: value"
}
:0 fhw
| $FORMAIL -rt ${hdr1+"$hdr1"} ${hdr2+"$hdr2"}
And if you want to stack all headers to only one variable, it is
a bit of extra work. Below we use short variable names only because
of the line space: the calls fit on one line.
o field = all (f)ields stacked to one string.
o nl = continuation newline terminator of previous field
The recipe says: if *field* has previous value, set `nl' to newline
separator, later concat previous contents of *field* with possible
newline and new header field.
field # kill variable
:0
{
nl
nl = ${field+"$NL"}
field = "$field${nl}X-Header1: value"
}
:0
{
nl
nl = ${field+"$NL"}
field = "$field${nl}X-Header2: value"
}
:0 fhw # If we have something in *field*
* ! field ?? ^^^^
| $FORMAIL ${field+-A"$f"}
The above recipe was the most general one, each recipe determined
by itself if the *f* existed previously or not. But if you know
that *f* is already set, you can write simpler recipe:
:0 # We know f has value before our module
{
field = "$field${NL}X-Header1: value"
}
12.20 Formail -A -a options
You can't use option -A with -a or -I if the header name is the same.
Like below where you try to keep only the last definition of X-1,
but the first -A isn't seen when -a is applied.
formail -A "X-1: 1" -a "X-1: 2"
-->
X-1: 1
X-1: 2
Whereas; separate pipes give you the desired results.
formail -A "X-1: 1" | formail -a "X-1: 2"
-->
X-1: 1
formail -A "X-1: 1" | formail -I "X-1: 2"
-->
X-1: 2
12.21 Formail -e -s options
[david] I had a file of alternating `From' and `Date' lines and
wanted to convert it into an mbox.
formail -dem2 -s < input > mailbox
should have done it, right? Nope; `formail' `-s' took it all as one
message, even with -m1. When I edited in blank lines, the command
worked. My first reaction was that the -e option wasn't working as
advertised and that the blank lines were necessary after all.
Then I realized the real problem: there was no interruption in the
succession of valid header lines in the input for anything that
could look like a body. I could have put something other than blank
lines between each pair of headerfields and then -e would have done
its job, but as long as every additional line looked like a valid
RFC822 headerfield, even if its name was the same as one that had
appeared earlier, `formail' `-s' assumed that it was still the same
message's head.
13.0 Saving mailing list messages
13.1 Using subroutine pm-jalist.rc to detect mailing lists
Because I didn't have sendmail plus addressing capabilities
(explained in next section) I wrote module *pm-jalist.rc*. It
is included in the pm-code.zip
The subroutine tries to detect and derive the mailing list name
directly from the message. Many Mailing daemons: ezlm, smarlist,
listserv, majordomo use standardized headers from where the list name
can be picked. After this subroutine has been applied to message,
the variable `LIST' contains the mailing list name. You no longer
have to manually insert separate recipes for each new mailing list
you subscribe to, because this subroutine adaptively finds new new
mailing lists.
Once the mailing list name has been grabbed, you can easily "map"
or convert the name to any suitable folder name before saving it:
LIST LIST name Description of mailing list
(as grabbed) you want
--------------------------------------------------------------
jde java.jde Java Development Env
java java.prog Java programming
FLAMENCO flamenco Flamenco music
tango-l tango Argentine Tango dancing
tm-en-help tm-en Emacs TM mime package mailing list
w3-beta w3 Emacs WWW mailing list
You set then conver grabbed `LIST' to new folder name with
conversion table:
JA_LIST_CONVERSION = "\
jde java.jde,\
java java.prog,\
FLAMENCO flamenco,\
"
And to detect all mailing lists, you only need one recipe, like
below:
INCLUDERC = $PMSRC/pm-jalist.rc
:0 : # if list name was grabbed
* ! LIST ?? ^^^^
$LIST_SPOOL_DIR/list.$LIST
13.2 Using plus addressing foo+bar@address.com
If you have a recent enough (8.8.8+) `sendmail', please ask your
sysadm to activate the plus addressing. Procmail gets `bar' in `$1'
automatically.
http://www.qz.to/~eli/faqs/addressing.html
http://www.faqs.org/faqs/mail/addressing/
[Bennett Todd ] The PLUS feature has also been
Implemented in *qmail* and *Postfix* (nee VMailer). By default
qmail uses "-" rather than "+", but it can be configured to use
different rules; Postfix doesn't come with either enabled, but its
example main.cf has a commented-out line to enable "+"-based
support.
[Roy S. Rapoport ] Plus addressing is
implemented using sendmail (well, I'm sure the other MTAs can also
do it, but my experience is with sendmail). The last few releases
of sendmail (8.8.6, 8.8.7, 8.8.8) all seem to automatically default
to allowing it. Basically, for any address of the form `foo+baz',
sendmail ignores the `+baz' part and just delivers it to foo.
If you want the easiest method to handle mailing list mails, then
subscribe to list by using dedicated plus address:
login+list.procmail@example.com
login+list.debian@example.com
login+list.linux@example.com
When you receive message from any of these mailing lists to your
`login' account, the `list.procmail' is already in variable `$1' and
the recipe to sink all mailing lists to their individual folders is
very simple:
# Note: The $1 contains value only _IF_ procmail
# is invoked with option -m or -a (with an argument).
# Be sure procmail is invoked with that oprion either as from
# LDA or ~/.forward.
#
# $1 is pseudo variable and it can't be used in condition line,
# so we copy the value to ARG.
ARG = $1
:0 :
* ARG ?? list
$ARG
[david] Here is what I have configured to sendmail.cf to support
plus addressing:
Mprocmail, P=/usr/bin/procmail, F=DFMmShu, \
S=11/31, R=21/31, \
T=DNS/RFC822/X-Unix, \
A=procmail -m $h $f $u
Well, this is definition of the procmail mailer, not the local
mailer. Furthermore, there's more to plus-addressing support than
the definition of the local mailer. Ruleset 0 or 5 needs to be set
up to move everything after the + into the 'host' variable ($h).
Unless you have a strong understanding of sendmail rulesets and
rewriting rules, you should not attempt to add plus-addressing to
your sendmail.cf, but instead just install the latest version of
sendmail and use the m4 sendmail.cf generation tools with a .mc
file that contains:
FEATURE(local_procmail, `/usr/local/bin/procmail')
plus whatever else your site requires.
...Ok, I corrected it. Well, here's what that looks like. I did
look into the part about Ruleset 5 while trying it on
originally. But all I could do was make sure that the
plus-addressing section was there.
Mlocal, P=/usr/bin/procmail, \
F=lsDFMAw5:/|@qSPfhn9, S=10/30,
R/40,
T=DNS/RFC822/X-Unix,
A=procmail -Y -a $h -d $u
Mprog, P=/bin/sh, F=lsDFMoqeu9, S=10/30, R/40, D=$z:/,
T=X-Unix,
A=sh -c $u
13.3 Using RFC comment trick for additional information
Recall from [rfc1036] that the preferred Usenet email address
formats are following
From: login@example.com
From: login@example.com (First Surname)
From: First Surname
I invented this idea after reading Eli's excellent faq about email
addressing. Please read it (especially section 19.) before you
continue in order to understand what I'm going to present.
I have an account which does not support plus addressing and I was
kinda jealous to everyone that could use this neat sendmail
addressing scheme. The plus addressing helps so much better to deal
with mailing list messages.
But as it turns out, we can simulate in some extent plus addressing
with pure RFC compliant address. We exploit RFC comment syntax,
where comment is any text inside parentheses. According to Eli's
paper, comments should be preserved during transit. They may not
appear in the exact place where originally put, but that shouldn't
be a problem. So, we send out message with following `From' or
`Reply-To' line:
first.surname@domain (First Surname+list.procmail)
Now, when someone replies to you, the MUA usually copies that
address as is and you can read in the receiving end the PLUS
information and drop the mail to appropriate folder: `mail.procmail'.
[About subscribing to mailing lists with RFC comment-plus address]
It's very unfortunate that when you subscribe to lists, the comment
is not preserved when you're added to the list database. Only the
address part is preserved. I even put the comment inside angles to
fool program to pick up everything between angles.
But I had no luck. They have too good RFC parsers, which throw away
and clean comments like this. Eg. procmail based mailing lists, the
famous `Smartlist', use `formail' to derive the return address and
`formail' does not preserve comments. The above gets truncated to
first.surname@example.com
Also many mailing lists send out messages as `Bcc', so your address
is not even available in headers anywhere, neither is this nice RFC
comment. Ah well, but this RFC comment trick works very well in
private communication, virtually all MUAs copy whole contents of a
`From' or `Reply-To' header to `To' header, preserving comments and
you get the benefit of plus addressing. Here is procmail code
to demonstrate reading the PLUS information from RFC comment-plus
field:
RC_EMAIL = $PMSRC/pm-jaaddr.rc # Address explode module
:0
*$ To:\/.*
{
INPUT = $MATCH
INCLUDERC = $RC_EMAIL # Explore grabbed To address
# If COMMENT_PLUS was defined, module found "+"
# address which contained, say, "mail.procmail".
# Save it to folder.
:0 :
* $COMMENT_PLUS ?? [a-z]
$COMMENT_PLUS
}
Pretty simple. And you can put anything inside RFC comment and do
whatever you want with these plus addresses. _NOTE_: there are no
guarantees that the RFC comment is preserved everytime. Well, the
standard RFC822 says is must be passed untouched, but I'd say it is
90% of the cases where mail is delivered from one server to
another, it is kept.
Example: if you discuss in usenet groups, you could use address
first.surname@example.com (First Surname+usenet.default)
first.surname@example.com (First Surname+usenet.games)
first.surname@example.com (First Surname+usenet.emacs)
first.surname@example.com (First Surname+usenet.linux)
13.4 Simple mailing list handling
[Peter S Galbraith ] I have used
this in the past (by simply looking at the spool file and seeing the
`From_' line of the message):
:0 :
* ^From debian
list.debian.mbox
:0 :
* ^From procmail
list.procmail.mbox
Now, I collect specific high-volume mailing lists (like Debian) into
their own spool files like above, and let other recipes catch all
other mailing lists (like procmail and fvwm) into a single spool
file with later rules:
:0 : # Majordomo lists
* ^Sender: owner-\/[-a-zA-Z0-9_.]*
list.$MATCH.mbox
:0 :
* ^X-Mailing-List: <\/[-a-zA-Z0-9_.]* # SmartList lists
list.$MATCH.mbox
So Debian mailing list mail goes to Debian, procmail and fvwm mail
go to maillists and mail addressed to me yet CC'ed to a list go to
my main spool file.
13.5 Archiving according to TO
Traditional way to detect and save mailing list messages is:
:0 :
* ^TO()procmail
list.procmail
[and so on...]
The following code will save the message to folders list.foo, list.bar,
list.procmail when the name is in the TO address.
# generalised version
# By dattier@wwa.com (David W. Tamkin)
# cases desired for foldernames
LISTS = "(foo|bar|procmail)"
:0:
* $ ^TO_()\/$LISTS
* $ LISTS ?? ()\/$\MATCH
list.$MATCH
13.6 Using Return-Path to detect mailing lists
[philip] For most mailing lists, a more accurate way to determine
whether it came from the list is to examine the Return-Path:, From_
or Resent-From: header. This catches messages from the list,
regardless of whether they were To: the list, Cc: the list, or even
Bcc: the list, something which doesn't show in the message at all.
For instance, I refile message from the procmail mailing list using
the following recipe:
:0
* ^Return-Path: + is not a bad idea, though because it's not a zero-width
assertion but rather an actual character class, you have to strip
it from the match
LISTS = "(foo-list|bar-list)"
# 1) to get the match
# 2) rematch sans the trailing \>
# 3) Note: preserves capitalisation of the string
:0
* $ ^TO_()\/$LISTS\>
* $ MATCH ?? \/$LISTS
* $ LISTS ?? ()\/$\MATCH
{
M = $MATCH
}
[Era] gives this sample example to describe what happens above:
VAR = "MOO"
what = "(moo|bar|baz)"
:0 # Search what from VAR
* $ VAR ?? ()\/$what
{
# Now; what is was that really matched, there were several
# choices: moo,bar,bar
# Beware: $MATCH must not contain regexp characters
:0
* $ what ?? ()\/$MATCH
{ } # no-op
# Fine, New MATCH contains moo
}
14.0 Procmail, MIME and HTML
14.1 Mime Bibliography
"List of annoying things that various MIME implementations do."
...The result is a sort of style guide for implementors of things that
generate MIME. Feel free to send comments or contributions.
http://www.cs.utk.edu/~moore/mime-style.html
14.2 Mime notes
[1998-07-28 PM-L Brett Glass ] MIME filename
buffer overflow bug described at
http://www.sjmercury.com/business/microsoft/docs/security0728.htm
This bug is particularly insidious because it can be exploited via
by spamming software and could impact millions of users in a very
short time.
Use procmail to plug the hole at the mail server, by truncating the
excessively long file names in the MIME headers: eliminate the
extra-long filenames, truncating them back to (say) 64 characters
max? All that's required is to recognize header below and make sure
that is chopped to a reasonable size.
Content-Disposition: attachment; filename=""
[era] I believe that the problem isn't really that the
filename is over the allowed length for some platform (Macintoshes
allow something like 27 characters if memory serves) but a bug in
how some particular email clients allocate memory for the file name
string (but I am really only speculating here).
...So far Eudora, Netscape Mail, Outlook Express, and mutt (Unix)
have all been found to have buffer overflow problems.
(mutt-0.93.2i and up are fixed. A patch for 0.93.1 is available.)
14.3 Software to deal with mime or html
See also nearest Perl CPAN module, http://www.perl.org, site and
CPAN/modules/by-module/MIME/
There's also Unix program `munpack' to explode a MIME message
to separate files. Use ftpsearch to find it.
[MIME aware mail agents in Unix]
See `mutt' that could handle HTML mail. (Pointer to Mutt
mentioned below)
All Emacs Mail agents can handle MIME if you install some of the
mime handling packages: TM, SEMI, rmime.el. See
http://www.bmrc.berkeley.edu/~trey/emacs/mime.html
14.4 Mime content type application/ms-tnef
...A member of one of my mailing lists appears to be using
Microsoft Mail. His messages to the list are usually accompanied my
an encoded attachment like this one:
"c:\eudora\users\steven@idma.com\attach\WINMAIL11.DAT" The message
headers include the following clause: Content-Type: multipart/mixed;
boundary="openmail-part-058c9f3d-00000001" This is driving people
crazy. What is causing this and is there any way to make it stop?
Most likely the sender is using Exchange (or Windows Messaging or
Outlook97) and sent the messages in Rich Text Format. It puts the RTF
message in an attachment called WINMAIL.DAT (application/ms-tnef). But
this attachment is useless unless the recipient is also using
Exchange.
The sender can turn off the RTF option for messages to you. For more
information, see: XCLN: Sending Messages In Rich-Text Format
http://support.microsoft.com/support/kb/articles/q136/2/04.asp
14.5 Trapping html mime messages
[era] Here's a simple filter to throw out unwanted html that is sent
by using mime. [jari] This recipe detects if the message is
classified as mime *text/html* and junks it to separate folder. It
does not change the message content. If you want to actually
remove html or other attachments from the message, see
`pm-jamime-kill.rc' in the module list.
:0:
*$ ^Content-Type:$s*multipart/(mixed|alternative);\
$SPCNL*boundary="?\/[^;"]+
* $ B ?? ^--$\MATCH\$([-a-z]+:.*)*Content-type:$s*text/html
junk.html.mbox
Some more examples can be found from section: 'Explaning ^^ and ^'
14.6 Complaining about html messages
[Marek Jedlinski ]. This how I
respond to html messages. In my `noHTML.txt' I politely explain
why I don't appreciate receiving HTML email, and ask to resend the
message as plaintext. What happens in the majority of cases is that
the sender resends the same message again ("oh, it bounced, let's
try again") and I assume they don't actually read my explanation
since they just happily resend the HTML cr*p. It bounces again at
which point they give up... Tough luck, I say ;)
BTW, the above recipe is placed *after* mailing list mail gets
sorted. When someone sends HTML mail to a mailing list I read, I
just flame them in person
TXT_NO_HTML = $HOME/noHTML.txt
:0 BH
* ! ^FROM_DAEMON
*$ ! ^$XLOOP
* ^Content.Type.+multipart.alternative
* ^Content.Type.+text.html
{
LOG = "$NL --TRASH: multi-part HTML $NL"
:0
| ($FORMAIL \
-rtk \
-A "X-Mailer: Procmail Autoreply" \
-A "$XLOOP" ; \
cat $TXT_NO_HTML \
) | $SENDMAIL
}
14.7 Converting HTML body to plain text
_Note:_ Older lynx has security holes:
http://ciac.llnl.gov/ciac/bulletins/h-82.shtml
http://lynx.browser.org/
The most popular solution to convert html body into plain text is to
use `lynx'. Another more straightforward method is to use a perl one
liner: it's quicker, easier to use with procmail but it doesn't pretend
to know about HTML DTD. The recipe below should be taken with grains of
salt: seeing HTML tag is no guarantee that the body "only" has html. A
cautious recipe writer also watches for MIME multipart messages. (See
`pm-jamime.rc' to draw some mime characteristics from message)
This recipe has been written so that you can add more alternative
html conversion scripts. You may even want to select the appropriate
conversion for a message: eg. perl for unimportant ones.
_Note_: This is oversimplified method of checking if body contains
html. It would be probably a good idea to check mime headers which
indicate html encoding here as well.
:0 B
* ()
* ()
{
conversion = "lynx" # or select this conditionally
:0
* conversion ?? lynx
{
# In new lynx version you can read from stdin. If
# /dev/stdin doesn't exits try /dev/fd/0
#
# lynx -dump -force_html -nolist -restrictions=all \
# /dev/stdin
#
# Without a global lock on this, you have a chance
# that two procmail instances will try to write to
# msg.dump
file = "$HOME/tmp/msg.dump"
LOCKFILE = $file$LOCKEXT
:0 fbw
| cat > $file && lynx -dump $file
LOCKFILE
}
:0 E fbw
| perl -0777 -pe 's/<[^>]*>//g'
}
14.8 Getting rid of unwanted mime attachments (html, vcard)
Microsoft and Netscape MUAs are conquering the PC world and it's
likely that you will receive messages from people that use this
software. The unfortunate thing is that you receive the message in
mime format:
HEADERS
--mime-boundary
plain text
--mime-boundary
Some idiotic html (or other type) copy of the text
--mime-boundary
When you would like to see a traditional message in the format:
HEADERS
plain text
Good news. There's a procmail module that addresses this problem. The
module can kill any mime attachment and the predefined sets include
typical cases:
o Microsoft Explorer has a bad habit of including 7k
application/ms-tnef attachment to the end of message.
o Lotus Notes sends similar extra attachment.
o Microsoft Express sends a copy of message in html format in the
attachment.
o Netscape's Mozilla sends a copy of message in html. See
example. It Also sends annoying `vcards'.
The module is called `pm-jamime-kill.rc' and included in Jari's
`pm-code.zip'.
(Note: #REF #procmail_module_list ;Procmail module list;)
14.9 Sending contents of a html page in plain text to someone
[timothy] Send an email with the subject: "GetPage:
some.url.here/". And it comes back. Kurt Thams
also pointed out that lynx allows file:// protocol and since
procmail is running as you, this would be a security risk.
GetFile: ~user/.login
We make the script safe here by forcing "http://$MATCH" and not
simply using "$MATCH"
:0
*$ ^Subject:$s+GetPage:()\/.*
*$ ! ^$MY_XLOOP
| ($FORMAIL \
-rt \
-I "Precedence: junk" \
-I "Subject: Requested page: $MATCH" \
-I "$MY_XLOOP" ; \
lynx -dump "http://$MATCH" \
)| $SENDMAIL
[era] If all you need is to create a suitable MIME package, there
are various MIME command-line utilities such as metasend (which is
for interactive use, and so doesn't work very well with Procmail)
and mpack you can try. If your needs are simple, you could even
read up a bit on the MIME spec and generate the necessary headers
and separators yourself (echo Content-Type: multipart/mixed etc etc
etc). Conversely, if your needs are complex, get the Perl MIME
package from CPAN and cook up your own tool. The MIME FAQ
(especially part 6) is a good place to look for info.
http://www.faqs.org/faqs/by-newsgroup/comp/comp.mail.mime.html
[jari] See procmail module list at the beginning of this
document for procmail based MIME file servers.
(Note: #REF #procmail_module_list ;Procmail module list;)
15.0 Simple recipe examples
15.1 Saving: MH folders -- numbered messages
Hm. This is explained in the procmail man pages, but not very
well. There are just one or two occasions where the man page tells
how to create individual files instead of catenating messages
to a folder. Notice the `/.' at the end of folder name
:0
* condition
dir-folder/.
[manual] When delivering to directories (or to MH folders) you
don't need to use lockfiles to prevent several concurrently run-
ning procmail programs from messing up.
On a save to a directory, how does procmail determine what to put
after $MSGPREFIX to complete the name of the file?
[philip] It's the inode number of the file encoded in
base-64 with the set of characters A-Za-z0-9-_, in reverse order.
So, for example, the inode numbered 59699 would be encoded as
follows:
59699 = 51 + 64 * ( 36 + 64 * 14 )
A=0, B=1, ..., N=13, O=14, ..., a=26, ..., k=36, ..., z=51,
0=52, ...
--> zkO
15.2 Saving: to monthly folders
# Use any date method mentioned previously to define variables
# YYYY YY MM DD. Archive digests monthly
:0 c:
* ^From:.*\/mailing-list-digest@some.net
{
# Get the "mailing-list-digest" string, do not use following
#
# MBOX = `echo $MATCH | sed -e 's/@.*//' `
#
# Because we really don't need those extra shell processes.
# Procmail can derive the word 10x more efficiently
:0
* MATCH ?? ()\/[^@]+
{
MBOX = $MATCH
}
:0 :
$YYYY-$MM-$MBOX
}
15.3 Modifying: Filtering basics
Pay attention to the `cat' command position in each recipe.
:0 fbw
| echo "This is a line of text _before_ the body"; \
cat -
:0 fbw
| cat - ; \
echo "This is a line of text _after_ the body"
:0 fbw # prepend text before the body
| cat msg.txt -
:0 fbw # append text at the end of body
| cat - msg.txt
:0 fbwi # replace the body with text from file
| cat msg.txt
15.4 Modifying: Squeezing empty lines around message body
[david] Anything that replaces the body is going to require an outside
process, even if it's only /bin/echo. In order to trim empty lines
from the beginning of message and from the end of message, you can
do this, if the entire body fits into `LINEBUF'
:0 B fbw
* ^^$*\/.(.|$)*.$
| echo "$MATCH" # trailing extra newline intended
If your version of cat is BSD-ish,
# SysV's cat has a different meaning for -s and cannot do this
:0 B fbw
* $$$
| cat -s
otherwise, it can be done with a very simple sed filter:
:0 B fbw
* ^^($)|$$$
| sed /./,/^$/!d
Note that cat -s has slightly different results from the others: if
there are any empty lines at the top of the body, cat -s will keep
one. The echo and sed suggestion will remove all empty lines from
the top and, like cat -s, keep one at the bottom.
15.5 Modifying: shuffling headers always to same order
[phil] To sort the headers in the message into predictable order,
you can use following recipe. The spaces have been eliminated
between the `-I' and its argument in the above. The shell may or
may not allow unquoted spaces in the second part of the
${variable:+blah}. For example, under solaris 2.6, /bin/sh barfs on
${FROM:+-I "From: $FROM"}, while /bin/ksh handles it just fine. I
think the POSIX shell standard requires that it be allowed, but,
well, will your _next_ system be POSIX compliant?
:0
* ()\/^From: +\/.*
{ FROM = $MATCH }
:0
* ()\/^Reply-To: +\/.*
{ RT = $MATCH }
:0
* ()\/^X-Mailer: +\/.*
{ XM = $MATCH }
:0
* ()\/^Message-Id: +\/.*
{ MID = $MATCH }
:0
* ()\/^Date: +\/.*
{ DATE = $MATCH }
:0
* ()\/^To: +\/.*
{ TT = $MATCH }
:0
* ()\/^CC: +\/.*
{ CC = $MATCH }
:0
* ()\/^Subject: +\/.*
{ SUBJ = $MATCH }
:0 fh w
| $FORMAIL \
${XM:+-I"X-Mailer: $XM"} \
${TT:+-I"To: $TT"} \
${FROM:+-I"From: $FROM"} \
${RT:+-I"Reply-to: $RT"} \
${CC:+-I"Cc: $CC"} \
${MID:+-I"Message-Id: $MID"} \
${DATE:+-I"Date: $DATE"} \
${SUBJ:+-I"Subject: $SUBJ"}
15.6 Service: Auto answerer to empty messages
[elijah] Here is piece of code that responds to empty
messages.
:0 B
* ! ...
| (echo "From: me@here.com" ; \
$FORMAIL -r -A"Precedence: junk" \
-A"X-Loop: me@here.com" ; \
echo "Your blank message was received.\n" \
"Did you mean to say something?\n" \
"\n" \
"-- \n" \
"My Signature\n" \
"this has been an automated response\n" \
) | $SENDMAIL
15.7 Service: File server -- send fileas as attachments upon request
This section is here only for indexing purposes. The File servers
are described in the #REF #procmail_module_list; Procmail module list;
15.8 Service: Ping responder
Sometimes I'm on the road and I don't seem to get access to the
site where my messages are. The telnet connection fails and
standard unix "ping" plays dead for me. "What's happening in that
site?" I wonder. Here is a recipe that I have added to all of my
accounts. It sends an immediate reply if at least the mailhost is
up and gives some status information.
:0
* ^Subject: ping$
{
:0 fh
| $FORMAIL -rt
# Remember, Don't send back anything that would be vital to
# attacker. It doesn't matter if the `uptime` or other
# scripts fail, the reply is sent anyway.
:0 c # Record this ping request
| ( cat -; \
echo `uptime`; \
echo "$HOST User count: " `who | wc -l`; \
) | $SENDMAIL
:0 : # or sink to $DEFAULT
$PING_SPOOL
}
15.9 Service: simple vacation with procmail
Don't forget to look into procmailex(5) man pages which also has
vacation example. The ones presented below may not work for you.
Here is a very simple vacation recipe. Whenever the file ~/.vac
exists, the vacation program is called. Be sure that you have the
~/.vacation.msg file ready too. Remember that `vacation' does not
_save_ you messages; so we need `c' flag here.
# Some prefer the non-dotted file which shows up in ls listing
vacationFlagFile = $HOME/.vac
:0 wc
*$ ? $IS_EXIST $vacationFlagFile
| vacation $LOGNAME
Some people like to raise a flag in .procmailrc instead of creating a
file. If you like the variable approach better, here is the equivalent
implementation of the above
VACATION = "yes" # Comment this when not in vacation
:0 wc
* VACATION ?? yes
| vacation $LOGNAME
[philip] and [era] Since vacation only sends replies -- it
never sends the original # messages, one way to do two things with
your .forward file. Substitute "abc" with your login name.
|/usr/ucb/vacation","exec /usr/local/bin/procmail -f- ||exit 75 #abc
15.10 Service: vacation code example
[By Eric Black ] Here is the procmail part
OFFSITE = "my_guest_login@wherever.I.am"
# Forward urgent mail to me at my offsite address; afterward,
# continue processing it as normal The procmail pattern match
# may be case-insensitive, in which case this rule could be
# simplified...
:0 c
* ^Subject: .*urgent
| $SENDMAIL $OFFSITE
# Use "vacation" to tell other people I'm not here To enable,
# un-comment the next two lines; to disable, comment them out
#
# The -a Identifies another name that can legitimately
# appear in the To: line of the mail header instead
# of your login name
:0 wc
| vacation -a ericb eric
And here the ~/.vacation.msg file
Subject: I'm out of town for a while
From: eric (via the vacation program)
I'm out of town until . Your mail regarding
"$SUBJECT"
will be read when I return, or possibly at some unknown
time before then if I get a chance to check for email.
If your message must be seen by me before I return,
you can send it with the word "URGENT" in the subject header.
Such mail will be automatically forwarded to me so that
I see it sooner.
--Eric
15.11 Service: Auto-forwarding
[timothy] I have my .procmailrc setup to forward email to another
(email only) account. When I am not going to be at the account, I
want to turn forwarding off
# look for the file to tell us whether or not to forward mail
# if the file exists, forward the mail
# or not
ELSWHERE = "me@elsewhere.com"
FILE = "$HOME/.forwardmail"
:0 c
*$ ? $IS_EXIST $FILE
! $ELSWHERE
# if a message arrives from the other account
# with the Subject 'forward-off' then remove the
# file, effectively turning off forwarding
:0 hwic
*$ ^From:.*$ELSWHERE
* ^Subject: forward-off
| $NICE mv -f $FILE $FILE.off
# if a message arrives from the other account
# with the Subject 'forward-on' then remove the
# file, effectively turning off forwarding on
:0 hwic
*$ ^From:.*$ELSWHERE
* ^Subject: forward-on
| $NICE mv -f $FILE.off $FILE
15.12 Service: forward only specific messages
Here is piece of code that triggers forwarding according to
addresses. If you have lot of these kind of forwarding,
you should use simple `awk' database which you would grep.
# By Jim Hribnak
# info@domain1.com goes to joe@domain1.com
# info@domain2.com foes to fred@domain2.com
:0
* ^TO_()info@domain1.com\>
{
FORWARDTO = "$FORWARDTO joe@domain1.com"
}
:0
* ^TO_()info@domain2.com\>
{
FORWARDTO = "$FORWARDTO fred@domain2.com"
}
:0 fhw
* FORWARDTO ?? @
* ! ^$MY_XLOOP
| $FORMAIL -A "$MY_XLOOP"
:0 a
! $FORWARDTO
15.13 Service: Making digests
# By
# Add this message to the digest accumulator
:0 c:
| $FORMAIL -k -X From: -X Message-Id -X Date -X Subject >> $DIGEST
#Check size of digest, and send it off if it's big enough
:0
* $ -$DIGSIZE ^0
* $ `wc -l <$DIGEST` ^0
| $NICE send-digest $DIGEST
15.14 Kill: killing advertisement headers and footers
A mailing list that I subscribe recently began adding a block of
"boiler plate" text to the beginning and end of every message
that goes through the list (groan). The text is always the same,
and is always at the beginning and end of the message.
[david] sed could do both at once, but the problem is that
sed never knows when it is N lines from the end if N>0; it knows
the last line when it reads it, but when it is looking at the
next-to-last line it doesn't know that there is only more one line
to come. It does, however, know how many lines of input it has
already read.
So I have three suggestions: if you know that the header is X lines
long [let's say 5 for this example] and that the first line of the
footer contains some string or pattern that will not occur in the
significant part of the post,
:0 fbwi
* conditions
| sed -ne 1,5d -e '/pattern/q' -e p
If you recognize the end by the last line that you want to keep
instead of the first line that you want to delete, omit the n
option and the p instruction:
| sed -e 1,5d -e '/pattern/q'
Finally, if the only reliable way to spot the footer is by reaching
so many lines from the end (because any search pattern might occur
in the real text as well), we can score as you've been doing to get
the number of the last significant line. Let's say the footer is
three lines long; because ^.*$ always counts one line too many
(long story), we subtract four instead of three:
:0 fbwi
* conditions
* 1^1 B ?? ^.*$
* -4^0
| sed -e 1,5d -e "$="q
15.15 Kill: simple killfile recipe with procmail
Kill files are widely used with newsreaders to delete uninteresting
posts when you enter a newsgroup. A kill file usually contains one
single entry per line to match the message content and this can be
easily done with procmail. Remember however that for every message
procmail forks a process, so before you apply the killfile rules to
the messages, be sure your recipes are in this order: the killfile
rules are applied only to *unknown* messages
SINK MAILING-LISTS
SINK ANNOUNCEMENTS
SINK WORK MESSAGES
OTHER DELIVERIES
apply killfile rules and UBE recipes to the rest
Recipe will drop the message (i.e. consider it 'delivered') if one
of its headers matches a pattern in killfile.
:0 hW: $HOME/.killfile$LOCKEXT
| egrep -i -f $HOME/.killfile
The reason why there is explicit lockfile is that you must be able to
update the killfile while your procmail is running. An example edit
script is presented below.
#!/bin/sh
# program: killfile.sh
#
file=$HOME/.killfile
lock=$file.lock
cp $file $file.tmp
emacs -q $file # or use whatever you prefer: vi, pico
lockfile $lock
mv $file.tmp $file
rm -f $lock
15.16 Kill: duplicate messages
[Lars Kellogg-Stedman ] Put this as a first entry in
your .procmailrc and you won't see any duplicates as long as the 8K
cache doesn't get full. The duplicates folder is cleaned out
weekly via a cron job. While it may be tempting to simply sink
duplicates to /dev/null, I have come across broken mail clients the
stick the same value in the `Message-id' header of all outgoing
mail.
:0
* ^Subject:\/.*
{
SUBJECT = $MATCH
}
MID_CACHE_LEN = 8192
MID_CACHE_FILE = $PMSRC/msgid.cache
MID_CACHE_LOCK = $PMSRC/msgid.cache$LOCKEXT
LOCKFILE = $MID_CACHE_LOCK
# IF the message has a message-id header
# AND formail -D is successful (exit status=0)
# THEN
# log a message to the procmail log
# sink the message
:0
* ^Message-Id:
* ? $FORMAIL -D $MID_CACHE_LEN $MID_CACHE_FILE
{
LOG="dupecheck: discarded message, $SUBJECT $NL"
:0 # Store duplicates, notice no lock!
duplicate.mbox
}
LOCKFILE # Release lock by killing variable
And here is a bit simpler recipe, a slightly modified version from
the [manual]. Procmail notices formail's success, considers the
message delivered and does not stop processing the rcfile due to
`c' flag, which let's a message to fall into safety copy inbox.
:0 hWc: $PMSRC/pm-msgid.cache$LOCKEXT
* ^Message-id:
| $FORMAIL -D 8192 $PMSRC/pm-msgid.cache
:0 a:
duplicate.mbox
There was a pretty heavy thread around September 1997 about
duplicate detection, where some promising stuff was posted. One
item you should definitely have in your collection is Eli's `hashd'
Matt Saroff also started a thread about duplicates:
where several of the replies are also helpful.
15.17 Kill: spam filter with simple recipes
[Ed McGuire ] Seeing several junk mail filters
posted recently, varying from the simple to the complex, I thought
I would also share my own. I junk whatever comes from my ISP but is
not addressed to my domain or to one of the mailing lists I
subscribe to.
# 1. mail to my domain
# 2. NOT addressed to me directly
# 3. NOT coming from mailing lists I'm subscribed to.
0:
* ^(received):.*psi\.com
* ! ^((apparently-)?to|cc):.*(i2|intellection)\.com
* ! ^(to|cc):.*(pdp-?8-lovers|procmail|sunshine|info-pdp11)
junk.ube.mbox
[Gordon Matzigkeit ] I have just discovered an
effective rule for separating SPAM from the rest of my e-mail.
Just substitute your username for `gord' in the line below
# Anything which is not addressed to me is probably SPAM.
:0:
* !^TO().*\
junk.ube.mbox
This only works because I handle all mailing list addresses above
that point in my .procmailrc (i.e. all traffic that arrives from
mailing lists that I am subscribed to goes into other folders).
Most SPAMmers seem to do it nowadays by sending mail via mailing
lists, rather than creating huge `To' lists of users
Many times sysadm install a list of know addresses that
send spam and then they check the incoming mail against the "black
list". Keep in mind that that some `fgrep' implementations have a
problem with the -w word switch. Note that the above recipe scans
the FULL HEADER, so use it with some caution, i.e., be careful what
you add to your list of spam domains.
# by [philip]; egrep would do here too, if it is posix
# compliant, it may have -f switch that makes it behave
# like fgrep.
#
# Note: option -F would make [ef]grep to search fixed string
# instead of regexps.
#
BLOCK_FILE = $HOME/Mail/DeniedNames.lst
UBE_MBOX = $HOME/Mail/junk-ube.mbox
# To filter out the Subject lines, so that emails sent
# with the subject "Have you received a message from
# blah-blah@spam" don't get filtered.
# [era] suggested we use formail
#
# Edsel Adap agrees there is a
# likely bug in Solaris 2.5.1 "/usr/bin/fgrep -i" and
# suggested the use of /usr/xpg4/bin/fgrep instead.
#
# Sun Microsystems Developer Support
# Files in /usr/xpg4 are available via the SUNWxcu4 package,
# which is part of the user, developer, all, or Xall Solaris
# clusters.
#
# Solaris 2.4 doesn't have /usr/xpg4/bin/fgrep :-(, you
# must use `tr A-Z a-z' before piping the message to fgrep.
:0 hw:
*$ ? $FORMAIL -ISubject: |fgrep -i -f $BLOCK_FILE
$UBE_MBOX
The file DeniedNames.lst is simply a list of addresses
82338201@compuserve.com
Dwnliner@ix.netcom.com
Emerald@earthstar.com
FreeWay@dm1.com
15.18 Kill: (un)subscribe messages
I'm getting tired of those pesky (un)subscribe messages that
certain "other" mailing lists seem to pass through to the list at
large instead of capturing them at the list server, like SmartList
does.
[Adam Shostack ] The following do help,
although they're often too broad. (I use a .safe rule to cover those
cases) The < 1000 is a useful hueristic. It's rare that unsubscribe
messages are long.
:0 :
* (Delete|u*n*Sub(s| )*| add | leave | help )
* < 1000
junk.misc.mbox
[Rodger Anderson ] I've been
working on a recipe to filter out those pesky s*bscribe and
uns*bscribe messages from mailing lists, and I'm posting what I have
so far. As an aside, it also filters out very short messages, which
I've found are usually some sort message meant for list owner/request
address.
I give heavy weight to Subjects starting with (un)?s*bscribe, with
also pretty heavy weight to Subjects containing either of those
words. I then give heavy weight to the body of messages starting
with those words, and a lighter weight to lines starting with them.
Then multiple occurrences get some weight too, up to a point. Then I
count the words in the message against all that.
:0 B
* 1^0
* 30^0 H ?? ^Subject: +(un)?subscribe\>
* 20^0 H ?? ^Subject:.*\<(un)?subscribe\>
*$ 20^0 ^^$SPCNL*(un)?subscribe\>
*$ 10^0 ^$SPC*(un)?subscribe\>
* 8^.4 \\<(un)?subscribe\>
* -.4^1 \\<$a+\>
junk.misc.mbox
[Adam Shostack ] How about looking for sub &
unsub, as well as a perennial misspelling 'unsuscribe me'? I also
find filtering on add, leave and help to be useful. This may well be
the only word on the line. I think it has to do with broken list
management packages.
| :0B
| * 1^0
| * 30^0 H ?? ^Subject: +(un)?subscribe\>
* 20^0 H ?? ^Subject: +(un)?sub?(scribe)?\>
(The B is often missing, as is the word fragment 'scribe')
| * 20^0 H ?? ^Subject:.*\<(un)?subscribe\>
* 20^0 H ?? ^Subject: +(add|leave|help)$
# fewer points if more words
* 15^0 H ?? ^Subject: +(add|leave|help)
[david 1998-10-20] You want to match on messages where the
first non-blank thing in the body is "unsubscribe" at the end of a
line, where there are five lines or fewer in the body?
:0 B
*$ ^^$SPCNL*unsubscribe$
* 7^0
* -1^1 ^.*$
junk.misc.mbox
^.*$ always counts one line too many, so a five-line body will be
counted as six; that's why we need a prejudice of 7. But if the
first non-blank text in the body is "unsubscribe" alone on a line,
is a line count really necessary? True posts that include the word
will have it in the middle of a sentence, such as the preceding
one. What you'll find by specifying a line limit is that
unsubscribe requests with long signatures or attachments at the
bottom of a previous message will get through.
15.19 Time: Once a day cron-like job
[Bill Moseley ] If you want to do something only
once a day, they you have to store the date somewhere and check
against that stored date.
YYMMDD_FILE = $HOME/.yymmdd
YYMMDD = $YY-$MM-$DD
# Contains single line of procmail code
# YYMMDD_PREV = ..
INCLUDERC $YYMMDD_FILE
# If different date, then enter this block
# The echo updates stamp in file.
:0
*$ ! YYMMDD ?? ^^$YYMMDD_PREV^^
* ? echo "YYMMDD_PREV = $YYMMDD" > $YYMMDD_FILE
{
...do the cron jobs..
}
15.20 Time: Running a recipe at a given time
If I put a program to my recipes, it will be executed every time
message arrives. That's a problem, and I'm not allowed to use cron
in this account. I'm looking for some sort of condition to check
the current time and if its outside of the hours 11pm and 7am then
execute the action.
[david] How do your From_ lines look? If they're the traditional
kind that sendmail and smail add, they include the local time on your
system at receipt. So include a check that the hour is between 07
and 22 inclusive, like this:
:0 c
* ^From .*some-address.* (0[789]|1.|2[012]):[0-5][0-9]:
| command
I included the minutes and the colon that separates the minutes from
the seconds so that the expression for testing the 07-22 range can
match only on the hour.
15.21 Time: Triggering email and using cron
[david] Put something like the following entries in your personal
crontab for your userid (and not knowing if you particular cron
"cd's" to your home directory first):
0 23 * * * touch $HOME/.mail.relay.on
0 7 * * * rm -f $HOME/.mail.relay.on
And if your cron doesn't know the HOME variable (that'd be an
exception)
0 23 * * * /bin/csh -c 'touch ~LOGNAME/.mail.relay.on'
0 7 * * * /bin/csh -c 'rm -f ~LOGNAME/.mail.relay.on'
Then, in your .procmailrc do:
:0 c
* ^From.*some-address
*$ $IS_FILE $HOME/.mail.relay.on
| command
the script will run_my_program only if both the subject matches and
the file test succeeds. The file test will succeed only between 11pm
and 7am.
In all honesty, if system gives usable From_ lines, I like following
suggestion better. I use it all the time to turn blocks of procmail
code on and off at given times or dates, and it works likes a charm.
It uses many fewer processes and is less likely to get the status
wrong if for any reason one of the cron jobs fails to run or doesn't
do its job.
This pages only at day time
:0 c
* ^From .*some-address.* (0[789]|1.|2[012]):[0-5][0-9]:
| command
This pages at night
:0 c
* ^From .*some-address.* (0[0-6]|23):[0-5][0-9]:
| command
15.22 Decoding: Uudecode
[philip] here is piece of code to do uudecode match when certain
condition is matched. The magic string here is "begin ...file",
the *body* is then fed to `my_uudecode_program' whatever it does
to it.
:0 b
* ^From:.*someone@somewhere\.com
* ^Subject: Subject
* B ?? ^begin 644 file.tar.gz
| my_uudecode_program
15.23 Decoding: MIME
# by Peter Galbraith
# MIME filtering of accented characters and split lines.
#
:0
* ^Content-Type: *text/plain
{
:0 fbw
* ^Content-Transfer-Encoding: *quoted-printable
| mimencode -u -q
:0 A fhw
| $FORMAIL -I "Content-Transfer-Encoding: 8bit"
:0 fbw
* ^Content-Transfer-Encoding: *base64
| mimencode -u -b
:0 A fhw
| $FORMAIL -I "Content-Transfer-Encoding: 8bit"
}
# 1995-10-18 Tim Pickett
#
# Decode MIME quoted-printable Content-Transfer-Encoding
#
# Conditions
#
# Mail has a MIME-Version header with a number in it.
# Header saying "Content-Transfer-Encoding: quoted-printable"
# exists
:0
*$ ^MIME-Version:$s*$d*(\.$d*)
*$ ^Content-Transfer-Encoding:$s*quoted-printable
{
:0 fhw # Remove header
| $FORMAIL -I"Content-Transfer-Encoding:"
:0 fbw # Decode the body.
| mmencode -u -q
}
15.24 How to send commands in the message's body
:0 b
* ^Subject: ARCHIVE
| sed -e '/$s*[^a-zA-Z]/,$ d' | sh
15.25 Matching two words on a line, but not one
How does one write a recipe that will do this: Put mail in mailbox
which has a line with two string (one and two) like:
one two
but save mail in error-folder if the line as only the first
string like: one (string two is missing)
[philip] I presume these lines would be located in the body of the
message, and that by "space between one and two" you mean
"whitespace between one and two". If those assumptions are wrong
then you'll need to tweak the following recipes:
# The 'B' tells procmail to look in the body instead of the header.
# The second colon tells procmail to lock the mailbox with a
# locallockfile -- if mailbox is a directory then you don't need
# it. The brackets in the condition contain a space and a tab.
#
:0 B:
*$ one$s*two
default.mbox
:0 B:
* one
error.mbox
Now, the above will match even if "one" or "two" is part of another
word (at the end in the case of "one" and at the beginning in the
case of "two"). If you don't want that then you'll need to change
the recipes to read:
:0 B:
*$ ()\
default.mbox
:0 B:
* ()\
error.mbox
15.26 How to define personal XX macros?
By macro, I'm referring to the procmail's FROM_DAEMON, TO and TO_
that you can use in matches. Here is one way to make one's own macro
[alan] Define HEADERS to include those headers you care about. Pick
one of the definitions below (and remove or comment out the
others). Here are three ways to define user `to_' macro
. use only To:
. use either To: or Cc:
. To:, Cc:, or Apparently-To:
to_ = '^To:(.*\<)?'
to_ = '^(To|Cc):(.*\<)?'
to_ = '^((Apparently-)?To|Cc):(.*\<)?'
And you use it like this
:0 :
*$ $to_()foo@bar.com
address-matched.mbx
[jari] and here are some more examples
cc_ = "(^((Original-)?(Resent-)?(Cc|Bcc)):(.*[^a-zA-Z])?)"
from_ = "(^(Apparently-|Resent-)*\
(From|Reply-To|Sender):(.*\<)?|\
^From $NSPC+)"}
15.27 How to change subject by body match
Suppose you to change the email's subject when there is a match in
the body. The desired outcome would be this:
From: foo@this.is
Subject: Fault: NNNN in program block YYY << changed
Fault: NNNN in program block YYY
Here is the answer
:0 fhw
* ^Subject: NOK case report
*$ B ?? ^$s*\/Fault: [0-9a-f]+ in program block.*
| $FORMAIL -I "Subject: $MATCH"
15.28 How to change Subject according to some other header
Suppose you want to change the subject when mail comes to some
particular address; or when some other header field. Here is one
way to do it, we suppose that mail comes to various internal mail
addresses. See the HEADERS macro in previous section.
# By [alan]
# Examine headers, create a subject tag if we recognize a list
TAG = ""
:0
* $ ${HEADERS}info@foo.com
{
TAG = "info"
}
:0E
* $ ${HEADERS}check@foo.com
{
TAG = "check"
}
# ...and so on...
# now, if TAG is set, insert it into the subject
MATCH # kill this
:0 fhw
* ! TAG ?? ^^^^
* ^Subject: *\/[^ ].*
| $FORMAIL -I "Subject: $TAG - ${MATCH:-}"
*Or* you could use the command line arguments, add following
line to your `.forward'. (alias file syntax)
foo: "|/usr/local/bin/procmail -m /usr/local/etc/pm-tagit.rc foo"
Then in `tagit.rc' you would instead say:
ARG = $1
:0
* ARG ?? ^^foo^^
{
TAG = "foo@go"
}
:0
* ARG ?? ^^somethingelse^^
{
TAG = "somethingelse@go"
}
This method will work even if someone Bcc:s a message to
foo@some.com.
15.29 How to call program with parameters
...now, suppose I want to call `program' with parameter $FOUND,
and get the result back in RESULT, how do I do it ?
The stdout of myprogram will be captured at stored in the variable
RESULT. Also consider what should happen if there are spaces or tabs
in the value of $FOUND. Perhaps it should be better off enclosed with
quoted.
# Make sure FOUND is not empty before passed to program
:0
* ! FOUND ?? ^^^^
{
RESULT = `program "$FOUND"`
}
16.0 Miscellaneous recipes
16.1 Matching valid Message-Id header
[philip] wrote full RFC compliant matcher. Follow the link
dq = '"' # (literal) double-quote
bw = "\\" # (literal) backwhack
ws = "[ ]*" # whitespace
atom = "[-!#-'*+/-9=?A-Z^-~]+"
word = "($atom|$dq([^$dq\]|$bw.)*$dq)'
local_part = "$word($ws\.$ws$word)*"
domain = "(\[$ws([^][\]|$bw.)*$ws\]|$atom($ws\.$ws$atom)*)"
:0
* ! $ ^Message-Id:$ws<$ws$local_part$ws@$ws$domain$ws>
thats-non-valid-message-id
16.2 Sending two files in a message
If you plan to send multiple files in a message, be sure that every
file has extra blank line at the end so that they can be *cat*d
together. Instead of doing
(cat THIS; echo " "; cat THAT ) | $SENDMAIL
You do
(cat THIS THAT ) | $SENDMAIL
But sometimes you don't have control over the files, then you can
do this to make sure there is blank line. Notice, only two
processes used compared to first choice.
(echo '' | cat THIS - THAT ) | $SENDMAIL
[David] And an sed expert would do it this way
(sed -e '$ !b' -e '/./G' -e "r THIS" THAT ) | $SENDMAIL
o $: the last line
o !: everywhere except the range (in this case, everywhere except
the last line)
o b: branch to a label. No label: branch to the end
(and, since -n is not in effect, print the pattern space)
Now remember that everywhere except the last line, we've
skipped ahead, so the rest of the code will be executed only for
the last line of the input.
o /./: on lines that contain a character (but we get here only for
the last line, so on the last line if it contains a character)
o G: append a newline and the contents of the hold space to the
pattern space (the hold space is empty, so basically, if the
last line was already empty, do nothing, but if the last line
was not empty, append a newline and thus add a blank line after
it).
o r file: After finishing with this run through the sed
instructions, read the named file and copy it to the output.
This side of sed comes out only after sed has had a few drinks...
16.3 Excessive quoting of message
[25 Nov 1997 buck@Compact.COM] I administer a LISTSERV mailing
list and our host has asked us to reduce excess quoting of
previously posted material. ...Subject: asking if this was
excessive quoting. With the weights below, this extra copy will
activate at 66% quoted lines of all body lines.
[era] I would definitely tolerate 75% quotes. And in the
end, you will of course always have to face the kinds of people who
would rather change their quoting style to evade such constraints
than quote less. An idealized quote parser should perhaps realize
that a non-blank prefix that recurs on a lot of lines is probably a
customized quote string.
This will preserve the correspondent's original subject (with a Re:
added if it didn't already have one) and thus the template text
should indicate the nature of the problem.
I'm not sure what would be appropriate to generate behaviour more
like I suggest below, any takers? Perhaps no score at all for empty
lines, neutralize .signatures (hope sender obeys "-- " convention)
and add 10^0.5 for each quoted line and dish out -15^0.3 for
nonquoted? (I haven't really explored this -- could be completely
up the creek.) [Also, perhaps long runs of quoted material should
be penalized harder than quoted snippet -- reply text -- quoted
snippet -- reply text alternations?]
COPY_ADDRESS = "listAdm@foo.com"
:0
* ^Sender:
{
# - quoted lines
# - non-blank, non-quoted lines
# - completely blank lines
:0B
*$ 10^1 ^$s*>
*$ -15^1 ^$s*[^>$WSPC]
*$ -15^1 ^$s*$
{
# You don't need to repeat the original condition here
# You also don't really need to extract SENDER
# Generate a reply with appropriate headers and the
# body quoted
:0 fhw
| $FORMAIL -rtk -A "Bcc: $COPY_ADDRESS"
# Now "replace" the body with template text + body (In
# other words, add the template before the quoted body)
:0 fbw
| cat $HOME/template.txt -
# Now send it off to recipients mentioned in generated
# header
! -t
}
# Wasn't excessively quoted; save it
:0 :
$SOME_MBOX
16.4 Sending message to pager in chunks
I have a 200 character limit on my pager. But I have wordy contacts
who go over that limit. What I would like to do is have a recipe
split up messages addressed to my pager into 200 character (max)
messages.
[era] This stuff about forwarding to pagers is a recurring
topic on this list. I've tried to find a good summary of all the
issues but there always seems to be some tiny twist to what people
would like to have implemented. As a general comment for future
generations, the Procmail part is usually trivial and the problem
reduces to writing a good program (shell script or otherwise) for
formatting the text precisely the way you want it, and spitting it out
in suitable chunks.
Here's something to split up the body of the message into smaller
chunks and do a shell script on each chunk. The -s option to fold says
to only wrap lines on whitespace if possible
# Create a duplicate of the message to forward to the pager.
# This will be reformatted and have most headers stripped off.
:0 c
{
# Construct header with only From: and Subject: retained
HEADER = `$FORMAIL -XFrom: -XSubject:`
# Reformat body as 200-character lines and send each
# as a separate message with the preconstructed minimal
# header
:0 bw
| tr '\012' ' ' | fold -s -w 200 | while read line; do
echo -e "$HEADER\n\n$line" | \
$SENDMAIL pageraddress@wherever.com ; done
}
If your version of echo doesn't understand \n to mean newline
(and/or the -e option to enable this escape processing), you need to
tweak this. (You might need to anyway -- this is mostly untested. In
my limited testing, I found the messages would arrive in more or less
random order. Inserting pauses in the script should help to some
extent, but could lead to other problems and is not an ideal solution
anyhow.)
I don't know if the header trimming is required; some pager gateways
appear to count the headers as part of the message, while others
don't. Again, for future generations, details like this are relevant
to include when you ask about how to do this.
16.5 Playing particular sound when message arrives
[Peter S Galbraith ] Here is the command
in shell to produce the sound:
% cat anyfile | /usr/X11R6/bin/auplay /usr/lib/exmh/drip.au
However, it won't work directly in the recipe
procmail: Executing "/usr/X11R6/bin/auplay /usr/lib/exmh/drip.au"
Can't connect to audio server
Strange. The command works from the shell if I `su' to user `mail'.
Anyway, I got it to work by fully specifying the audio server (which
is my workstation, where I receive mail)
AU = /usr/X11R6/bin/auplay
TUNE = /usr/lib/exmh/drip.au
:0 hwic
* ^From:.*foo@bar.com
| cat > /dev/null; $AU -audio tcp/mixing:8000 $TUNE
16.6 Combining multiple Original-Cc and Original-To headers
How can I use procmail/formail to combine the information in these
headers into their *CORRESPONDING* header MINUS the Original-*
Note that I can have multiple Original-Cc: headers and I want all
the recipients combined into one Cc: header.
# 1998-01 by [david]
# initialize as unset
ORIG_TO ORIG_CC
# The -c option to formail takes care of headers continued onto
# indented lines; the pipe to tr takes care of multiple
# Original-To: headers by linking their contents with commas.
:0
* ^Original-To:.*[^ ]
{
ORIG_TO = `$FORMAIL -zcxOriginal-To: | tr \\12 ,`
}
# Drop trailing comma from tr:
:0 A
* ORIG_TO ?? ,^^
* ORIG_TO ?? ^^\/.*[^,]
{
ORIG_TO = $MATCH
}
# Likewise for Original-Cc: lines:
:0
* ^Original-Cc:.*[^ ]
{
ORIG_CC = `$FORMAIL -zcxOriginal-Cc: | tr \\12 ,`
}
:0 A
* ORIG_CC ?? ,^^
* ORIG_CC ?? ^^\/.*[^,]
{
ORIG_CC = $MATCH
}
# Now, let's install the changes if needed:
# with -A instead of -I or -i it should
# not clobber existing To: or Cc: information.
# -A : Append a custom headerfield onto the header in any case.
:0
* ORIG_TO ?? ^^^^
* ORIG_CC ?? ^^^^
{ }
:0 E fhw
| $FORMAIL \
${ORIG_TO:+-A "To: $ORIG_TO"} \
${ORIG_CC:+-A "Cc: $ORIG_CC"}
16.7 Forwarding sensitive messages in encrypted format
# by [alan]
# See if addressed *directly* to me, and ..
# ..has not already been forwarded
KEY = "TheMagic"
FORWARD_EMAIL = "foo@bar.com"
:0
* $ ^To:.*$LOGNAME(@|[^0-9a-z]|$)
* $ ! ^$MY_XLOOP
{
# now let's encrypt the body using mimencode
:0 fbw
| echo "MIME-Version: 1.0" ; \
echo "Content-Type: application/crypt" ; \
echo "Content-transfer-encoding: base64" ; \
echo "" ; \
crypt $KEY | mimencode -b
# Now let's prepare the headers for forwarding the mail,
# and mark it so we don't loop
:0 fhw
| $FORMAIL -I"Resent-To: $FORWARD_EMAIL" -I"$MY_XLOOP"
:0
! $FORWARD_EMAIL
}
17.0 Procmail and PGP
17.1 Decrypt pgp messages automatically
_Warning_: if you use remailers or anonymous services, you must use
different passwords and different user id's to decrypt incoming
messages. If you just receive messages encrypted with one key, then
you this may be useful to you. However, it is generally considered a
huge security risk to keep your password carved into your .procmailrc.
:0 fbw
* B ?? PGP ENCRYPTED MESSAGE
| pgp -z "your pass phrase" -f +batch 2>&1
17.2 Getkeys from keyserver
# by Adam Shostack 1996-02
#
# This first ruleset protects me from mailbombs from an automated
# service that I often send incorrect commands to, generating 5mb
# of reply. It also sorts based on success of the command.
#
# swissnet.ai.mit.edu is fast keyserver
:0
* From bal@swissnet.ai.mit.edu
{
:0 h
* >10000
/dev/null
:0 h
*^Subject:.*no keys match
/dev/null
:0 E
| pgp +batchmode -fka
}
17.3 Auto grab incoming pgp keys
# [Opher Kahn ] This first ruleset protects
# me from mailbombs from an automated service that I often send
# incorrect commands to, generating 5mb of reply. It also sorts
# based on success of the command.
#
# swissnet.ai.mit.edu is PGP key server
:0
* From bal@swissnet.ai.mit.edu
{
:0 h
* >10000
/dev/null
:0 h
*^Subject:.*no keys match
/dev/null
:0 E
| pgp +batchmode -fka
}
# auto key retrieval
#
# I have an elm alias, pgp, points to a keyserver The logfile
# gets unset briefly to keep the elm lines out of my logfile.
:0 W
* B ?? -----BEGIN PGP
* H ! ?? ^FROM_DAEMON
{
KEYID = `/usr3/adam/bin/sender_unknown`
}
LOGFILE=
# #todo: We should get rid of the 'elm' dependency here.
# #todo: correct this sometime... [jari]
#
:0 ahc
* ! ^X-Loop: Adams autokey retrieval
| $FORMAIL -a"X-Loop: Adams autokey retrieval" | elm -s"mget $KEYID" pgp
#!/bin/sh
#
# Script: sender_unknown
#
# unknown returns a keyid, exits 1 if the key is known. $output
# is to get the exit status. Otherwise, this would be a one
# liner.
OUTPUT=`pgp -f +VERBOSE=0 +batchmode -o /dev/null`
echo $OUTPUT | egrep -s 'not found in file'
EV=$?
if [ $EV -eq 0 ]; then
echo $OUTPUT | awk '{print $6}'
fi
exit $EV
# end of sender_unknown
18.0 Includerc usage
18.1 Using: multiple rc files
...Do INCLUDERC statements function as a kind of "call" which
returns control to the "original" rc file if processing falls off
the end of the included rc file? Or if processing falls off the
end, does mail then get delivered to $DEFAULT and processing
stop? Suppose I have these commands
INCLUDERC = $PMSRC/pm-a.rc
INCLUDERC = $PMSRC/pm-b.rc
INCLUDERC = $PMSRC/pm-c.rc
Yes, the control is returned to the original file where the
includerc was called from. And No, mail does not get delivered in
the $DEFAULT because the includerc just ends: processing continues
until there is no more statements in the top level.
Includerc is nothing more that a sliced top level recipe.
18.2 Using: You can call rc file conditionally
One interesting way to prevent false hits when filtering UBE is to
try to see if the message comes from some valid destination
first. If it comes, then it shouldn't be run through UBE filter,
because it may filter valid messages out. No ube filter is
completely bullet proof.
Here is an example where the UBE detection is put into use only when
the message comes from somewhere that I don't know beforehand (or I
have just forgot to tweak my .procmailrc)
ME = "(me@here.is)"
LISTS = "(procmail|list-a|list-b)"
:0 # Idea by Bill Moseley
*$ ! ^TO_()$ME
*$ ! $LISTS
{
# Could be UBE or I might be on a unknown distribution list.
INCLUDERC = $PMSRC/pm-ubecheck.rc
}
[dan] That would work; common practice, however, is to put recipes
for filing mail from lists (and, per Bill's preferences, anything
mentioning procmail in the head gets treated the same as mail from
this list) first; then the only remaining condition to consider
there would be unexpected blind carbons: * ! ^TO_moseley. This
method is good if you get much more spam than legitimate mail
(including mail from list subscriptions as legitimate) and you want
procmail to deal with spam right away. I belong to several very
active mailing lists, so I actually receive more pieces of
legitimate mail than pieces of spam.
One way to get the best of both worlds is this:
* $ ! ()\/(^TO_$LOGNAME|procmail|list-(ABC|123|XYZ))
because then, if the regexp matches (and thus the negated condition
fails and you don't detour into $PMSRC/checkspam.rc), MATCH is
already set to the name of the mailing list, and you can do further
tests by just examining MATCH (or a variable you copy it into)
instead of a repeating a complete head search. [I prefer to use
the variable $LOGNAME rather than hard-coding my name because then
others can use the code, and I can use it unchanged on sites where
my logname is different, and if my logname is changed my
.procmailrc will keep up with it.] For example (I've separated the
conditions into two lines so that, per Bill's preferences, a
mention of procmail in the head will get the message into the
Procmail List folder, even if a match to $^TO_$LOGNAME is also
present and appears sooner):
:0
* ! ()\/(procmail|list-(ABC|123|XYZ))
* $ ! ^TO_$LOGNAME
{
INCLUDERC=$PMSRC/pm-ubecheck.rc
}
# The next recipe has an `E' flag, so it will be examined
# only if the preceding one didn't match; thus if $MATCH was
# set inside pm-ubecheck.rc, it won't hurt anything here, and a
# value for $MATCH set in pm-ubecheck.rc
# won't be mistaken for a list name:
:0 E: # MATCH is non-null only if it matched a list name
* MATCH ?? (.)
$MATCH
# Remaining recipes will be read only for two types of mail:
# those that met $^TO_$LOGNAME but not any expected list
# name, and those that went through pm-ubecheck.rc but came out
# undelivered.
18.3 Autoloading an rc file
Now when you know that includerc can be called conditionally, let's
discuss about "autoloading of module". For example I use following
statement in nearly all my modules to import predefined variables
:0
* ! WSPC ?? ( )
{
INCLUDERC = $PMSRC/pm-javar.rc
}
It says that "If variable WSPC does not contain space, then load
module". If the module has already been loaded by some other rc
file, the WSPC would exist. If it does not exist yet, then we load
the module. This is classical example of conditionally loading
functions or variables into current module:
Check if feature is present, No? Then load module module.
Justin Lloyd suggest a general way of caching
the included rc files. We use top-level script that records every
module that was included. The module is loaded only if it it not
yet included:
# pm-xximport.rc
:0
* ! INCLUDE_CACHE ?? ()\<$RC\>
{
# Module was not there yet, add it to the list
INCLUDE_CACHE = "$INCLUDE_CACHE$RCFILE$NL"
INCLUDERC = $RC
}
This different approach then the previous one. Instead of checking
features, the presense of module is checked. Two sides of the coin
which can be used for the same thing. You can pick either solution
but to my opinion
o Adding extra top level INCLUDE_CACHE is extra work. Procmail
must open a separate top-level rc file every time with call
RC="pm-xxscript.rc" INCLUDERC=pm-xximport.rc
o If feature already existed, you would still have to open the
pm-xximport.rc file for every call to find it out. Eg. Here you
pm-xximport.rc is called 3 times no matter if 1,2,3 were
already present
RC="pm-xxscript1.rc" INCLUDERC=pm-xximport.rc
RC="pm-xxscript2.rc" INCLUDERC=pm-xximport.rc
RC="pm-xxscript3.rc" INCLUDERC=pm-xximport.rc
o With simple feature test, procmail can evaluate the condition
in place without the need of opening separate file.
if no feature present..
then load
if no feature present..
then load
Note however, that both suggestions accomplish the same thing; the
implementation is only different. If the typical count of including
RC files per module were big enough, I'd use justin's way. Currently
the typical count is only 1-2 (VAR,DATE).
18.4 Making: naming of the rc file
When you write an rc file, think whether or not it could be
generalized so that others could use it. I have adopted style where
all procmail files start with prefix `pm', so that I can stack
other files as well to the same directory. If I simply named them
as `rc.*', look what happens:
% ls rc* # fine, print rc files
but I wold like to print all procmail relates files and backup
them with one command, so this would print all procmail relates
files
% ls pm-*
--> pm-mytest.rc
pm-jaube.rc
pm-tips.txt
pm-art.txt
pm-incoming.log
pm-list.mbox # the mailing list
I usually use a name like `pm-xxSCRIPT-NAME.rc' for a rc file where
`xx' is my initials from firstname and surname, like (J)ari
(A)alto. These scripts are product versions, that can be
distributed. I also have private scripts that handle my mailing
lists, work messages and so on and they have prefix `my'.
pm-jascript.rc
pm-myscript.rc
and when I download someone else's script I would like to see it
named so that it's unique to the person who did it.
pm-jdscript.rc # John Doe's script.
18.5 Making: Using namespace when saving procmail variables
If you're going to write rc file that works like any other
programming language subroutine, you must separate it from the
world and make it well behaving. A subroutine is traditionally a
black box: you call it with arguments and it responds with
returned values. You don't need to know what happens in there. And
you expect that the subroutine hasn't changed the existing
environment, like procmail variables `DEFAULT' `LOGFILE' etc. when
it ends.
So the process diagram of a good RC subroutine is:
pm-xxscript1.rc
call --> +------------+
arguments | black | --> it may call
| box | other subroutines
| | <-- pm-xxscript2.rc
output values <-- +------------+
Procmail does not have local variables, so you must put the
variables to global namespace. Let's see an example where
subroutine uses `MAILDIR' for `chdir' purposes.
MAILDIR_xxscript1 = $MAILDIR # save
...
MAILDIR = new location
...
...at the end of subroutine
MAILDIR = $MAILDIR_xxscript1 # restore
Here the original value is saved when subroutine started and the
original value was restored when subroutine exited. The global
namespace (xxscript1) used was unique and is guaranteed not to
clash with anyone else's. If the `pm-xxscript2.rc' would have also
used `MAILDIR' the saved value would have been in
PROCMAILVAR_xxscript2
and the two wouldn't mix up with each others `MAILDIR'. The general
name for saved variable is therefore:
PROCMAILVAR_scriptname
This follows the simple "onion" or "stack" model, where variable's
value is saved before changing it and restored on exit point.
save-x-1
set--x-1
save-x-2
set--x-2
..
restore-x-2
restore-x-1
18.6 Making: Public and private variables in rc file
As you learned above, the variables should be put to RC file's
namespace. The user interface variables (public) should be all caps
and private variable should start with lowercase letter. Whether
you use "theVarStyle" or "the_var_style" is up to you.
[script pm-xxscript.rc]
# ........................... public
XX_SCRIPT_FLAG = ${XX_SCRIPT_FLAG:-"default"}
XX_SCRIPT_VAR = ${XX_SCRIPT_VAR:-"default"}
# ........................... private
charset = "a-z1-2"
regexp = "something-that-matches"
Whether you need to stick prefix `xx_script' to the private variables
depends on whether you call another includerc which may happen to use
same names as you:
[pm-xxscript.rc]
charset = ... # watch this
...
INCLUDERC = .. # call another subroutine
charset = .. # holy cow, it used same variable
..back in the pm-script.rc
:0
* $charset # BOOM, not what you think.
In this case it would be wise a) not to define `charset' at the top
of the file but to move the definition to just before the recipe
where it is used or b) make the name unique, with
`pmScriptCharset'.
18.7 The rules of thumb for constructing general purpose rc file
o Write good documentation at the beginning of file: how to set up
the includerc and explain what it does. If you don't include
docs, people may skip your extraordinary useful script. Also,
remember that the script lives in the Net and passes through many
hands long after you have been disconnected.
o Keep the layout like this: the user interface variables must all
be in capital letters. Familiarize yourself with what(1) tags
too. Notice the first and last lines: if you keep the format
like this, then any universal tool can rip your code from any
file (or email), because it's delimited by "pm-xxScript.rc -- "
and "end of pm-xxScript.rc". See unix what(1) for first line's
syntax.
# @(#) pm-xxScript.rc -- procmail script for ...
# DOCS
USER VARIABLES
private variables
CODE
# end of pm-xxScript.rc
o Always include version number or last modification date somewhere.
Prefer some version control tool, like RCS, VCS, ClearCase,
whatever you have at hand.
o Use a variable name like `dummy' in appropriate places to tell
what's happening in the code. Remember that the *VERBOSE*
setting isn't much help if you can't tell by looking at the
*LOG* where on earth the code is executing.
dummy = "start of pm-xxScript.rc"
...
dummy = "Now testing if we have control message XXX"
:0
* condition
{
dummy = "Now testing if the command is YYY"
:0
* condition
...
}
...
dummy = "end of pm-xxScript.rc"
o If you need the value of some common headers, don't just call
formail like this because the value may already be available
prior your includerc. For example the user may already have needed
the *Subject* value and stored it in a variable
[in pm-xxScript.rc]
XX_SCRIPT_SUBJECT = `$FORMAIL -xSubject:'
[User may have already read the content to SUBJECT]
SUBJECT = `$FORMAIL -xSubject:'
INCLUDERC = $PMSRC/pm-xxScript.rc
Your pm-xxScript.rc launches an unnecessary formail call. Instead,
use the existing SUBJECT.
[user]
:0
* ^Subject:\/.*
{
SUBJECT = $MATCH
}
...
XX_SCRIPT_SUBJECT = $SUBJECT # Note this!
INCLUDERC = $PMSRC/pm-xxScript.rc
[ in the pm-xxScript.rc variable definitions ]
# User should initialise the variable
# XX_SCRIPT_SUBJECT if he already has read the
# subject.
:0
* XX_SCRIPT_SUBJECT ?? ^^^^
* ^subject:\/.*
{
SUBJECT = $MATCH
}
...the rest of the code
o _Add_ header `X-Loop' and test against it if you are sending an
automated reply. The `X-loop' prevents responding to already
responded message.
:0
* condition
* ! ^FROM_DAEMON
*$ ! ^$MY_XLOOP
{
# Ok, now we're clear to send an automated reply
}
18.8 An includerc skeleton
Here is my includerc file skeleton that i use in all my modules. The
funny looking ".$" are for the text2html Perl filter. The
documentation section can be ripped and turned into html very easily
is you just keep the standard 4 tab column positions and start the
description with "File id" and end it with "Change Log". The command
to make the html is:
% ripdoc.pl pm-xxscript.rc | t2html.pl > pm-xxscript.html
These two perl files are available from my ftp directory.
# @(#) pm-xxscript.rc -- one line description string here
# @(#) $Id: pm-tips.txt,v 1.76 1999/11/10 13:55:12 Jari Aalto Exp $
#
# File id
#
# .Copyright (C) 1997-98 Foo Bar
# .$Contactid: $
# .$Created: YYYY-MM $
# .$keywords: procmail [subroutine|recipe] whatItDoes $
#
# This code is free software in terms of GNU Gen. pub. Lic. v2 or later
# You can get newest version by sending email to maintainer with
# subject "send "
#
# Description
#
# This subroutine Parses from variable INPUT
#
# Required settings
#
# PMSRC must point to source directory of procmail code.
# This subroutine will include
#
# o pm-xxScriptA.rc
# o pm-xxScriptB.rc
#
# Call arguments (variables to set before calling)
#
# o INPUT, the string from where to parse...
# o VAR1, description, default is ...
# o VAR2, description, default is ...
#
# Returned values
#
# ERROR will have value "yes" if couldn't parse INPUT
# OUTPUT will have result after successful parse
#
# Example usage
#
# :0
# * condition\/.*
# {
# INPUT = $MATCH
# INCLUDERC = $PMSRC/pm-xxscript.rc
# # OUTPUT has the result
# }
#
# Change Log: (none)
# ..................................................... &init ...
dummy = "init: pm-xxscript.rc start"
# Read the standard variable definitions if they are not
# yet defined: that's "if WSPC variable does not contains space,
# as it should, then global variables haven't been read yet"
:0
* ! WSPC ?? ( )
{
INCLUDERC = $PMSRC/pm-javar.rc
}
# .................................................... &input ...
# - User configurable variables with reasonable defaults
# - But parameters like "INPUT" that must be set beforehand
# are not mentioned here.
VAR1 = $VAR1{VAR1:-"default1"}
VAR2 = $VAR2{VAR2:-"default2"}
# .................................................... &do-it ...
dummy = "subroutine: pm-xxscript.rc parses now that and that"
dummy = "subroutine: pm-xxscript.rc end."
# end of pm-xxscript.rc
19.0 Mailing list server
19.1 Mailing list server pointers
"Meng on procmail"
http://res2.resnet.upenn.edu/procmail
19.2 Simple Mailing list server
# by Lars Hecking
#
MAJORDOM = "majordomo-(users|docs|workers)"
:0 w
* $ ^(Sender|To|Cc):.*\/$MAJORDOM
* $ MAJORDOM ?? ()\/$\MATCH
| $APPNMAIL $LISTS/$MATCH
Here is another, by Brock Rozen with ideas
from [dan]
# get the date in RFC822 format for insertion into some messages;
# the "Resent-Date:" field is copied from the "Date:" field on
# some systems. RFC1123 says "All mail software SHOULD use 4-digit
# years in dates..."
LIST_NAME = "myList"
LIST_ADDR = "$LSIT_NAME "
LIST_DATE = `date '+%a, %d %h %Y %H:%M:%S %Z'`
LIST_ERR = "$EMAIL" # my admin address
# Sendmail ignores "To:" in the presence of "Resent-To:"
#
:0 fhw
*$ !^X-List: $LIST_NAME
*$ ^TO()$LIST_NAME
| $FORMAIL
-A "X-List: $LIST_NAME" \
-I "Resent-To: $LIST_ADDR " \
-i "Resent-Date: $LIST_DATE" \
-I "Errors-To: $LIST_ERR" \
-A "Precedence: bulk" \
-A "X-Loop: $COMSAT"
:0 a
! -oi `cat /var/tmp/src/power-users.list`
20.0 Common troubles
20.1 Procmail modes: normal, delivery, and mailfilter.
... a) what recipes procmail goes through if there's no
/etc/procmailrc on the system b) how it decides whether an
address/local-part is valid or not c) how procmail selects the
mailbox to drop the email
[philip] *Delivery* mode is invoked using the -d flag. All
arguments are the -d are usernames. It is usually used by the MTA
to deliver mail to users, and indeed, procmail will return failure
if it is given an invalid username. In delivery mode, procmail
reads /etc/procmailrc before the user's .procmailrc.
_Note_: Procmail will work in delivery mode only if it is
setuid root, if it is invoked with the ruid of the recipient named
in -d, or, under certain OSes where the build routines have
determined that it is safe, if the euid is that of the recipient
and the egid is the recipient's login group.
*Mailfilter* mode is invoked using the -m flag. It accepts
only one rcfile as an argument -- other arguments are either
variable assignments or arguments that are made availible to the
rcfile itself as $1, $2, etc. If the specified rcfile is located
under /etc/procmailrcs/ then procmail will take on the uid of the
owner of that file. Otherwise, it will run as the user who invoked
it. /etc/procmailrc, that procmail -d reads, is ignored. In
mailfilter mode, procmail unsets `ORGMAIL' and `DEFAULT' to
suppress normal delivery -- reaching the end of the rcfile results
in the mail bouncing. If the rcfile sets either of them then
procmail will attempt delivery to that mailbox if it falls off the
end of the rcfile; however, the mailbox will have to be writable by
the uid/user that procmail is running as.
_Note_: Only one rcfile can be named on the command line, but names
of other rcfiles can be passed in the positional parameters to be
used later in INCLUDERC assignments.
*Normal* mode is invoked by not using the `-m' or `-d' flags. It
accepts any number of rcfiles and variable asssignments as
arguments. Procmail runs as the invoking user in this mode.
/etc/procmailrc is ignored.
So, to answer your questions: if procmail reaches the end of the
specified rcfile, it bounces the mail (/etc/procmailrc is ignored).
Everything is up to the rcfile -- how to determine whether the
address is valid and where to put the message if it is.
20.2 Procmail as sendmail Mlocal mail filtering device
...I'm a new sys admin at my company, and I've been trying to set up
Procmail as the mail filtering device (still using mail as the
Mlocal) I've tried setting up the sendmail.cf to use Procmail as
a filter (we want to use the current mailer as the local mailer)
with one local procmail rc file. Procmail seems to work just fine
if set up as the local mailer, but I'm still having problems
setting it as the filter.
[John M Vinopal answers sendmail.cf]
R$+ < @ $=a . > $*
$#procmail $@ /etc/mail/procmailrc $: $1 < @ procmail > $3
R$+ <@ procmail > $* $1 < @ resort.com .> $2
so this sends anything of the form foo@resort.com through procmail
and rewrites it as foo@procmail. the procmail script reinjects it
and it bypasses the call to procmail and then is rewritten back to
foo@resort.com.
/etc/mail/procmailrc:
:0
! -oi -f "$@"
20.3 Procmail doesn't pass 8bit characters
You've mistaken. Procmail does not do that to your mail.
Frank Gadegast tells you:
o procmail wasnt the problem, it was sendmail
o I uncommented this line in sendmail.cf
and now I get all nice German Umlauts.
# strip message body to 7 bits on input?
# O SevenBitInput
The problem was that some mails run through the local mailer
procmail and arrived all right (local mail), all mail from external
(that dropped into my most used mailbox where I use a
procmail-filter), did not arrive all right. This made me think it
procmail, but these mails came from external and it was sendmail to
blame.
20.4 My ISP isn't very interested in installing procmail
...I recently requested my ISP to install procmail, and they
responded by saying no. Their main reason was they did not wish to
incur the traffic from any/ all of their subscribers setting up
mailing lists.
[Jon Lewis ] Wouldn't you need
write access to either /etc/aliases or /etc/procmailrc to setup
mailing lists? Tell the ISP that procmail will greatly improve mail
delivery and enable all users to filter out junkmail without ever
seeing it. If they still refuse, find a better ISP.
20.5 My ISP has systemwide procmailrc; is this a good idea?
[eli] I, for one, do not like my ISPs to put stuff in
/etc/procmailrc. There is precious little I will gain from that and
plenty of opportunity for them to make mistakes I would not have. At
one ISP I know people got upset at some sendmail level filtering of
email. One of those upset is a habitual complain-to-spammer-ISP
person. He did not want problems seeming to go away if they were
really there. Another guy just didn't trust the filtering.
Writing a shell script that will give the user a .procmailrc which
includercs a system wide shared procmailrc is the best way to do it.
This forces the filtering to be "opt-in".
20.6 Procmail changes mailbox and directory permissions
By Ed McGuire . Before procmail was used:
> -rw-rw---- 1 foo mail 1127 Sep 11 07:33 foo
After:
> -rw------- 1 foo mail 1517 Sep 11 07:34 foo
when the UMASK environment variable is more restrictive than the
mode of the mailbox, procmail changes the mode of the mailbox. The
default value of UMASK is 077. If you want to preserve the group
access to your mailbox, I think you can set UMASK to 007 in the
rcfile:
UMASK = 007
Further note: the above `UMASK' suggestion in .procmailrc does not
work. See comment by Gjermund Sørseth
However the permissions on `DEFAULT' are handled before procmail
even opens the .procmailrc, so changing the umask there will have
no effect on the mailspool.
[Scott J. Kramer ] it's documented in the MISCELLANEOUS
of the procmail(1) man page:
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.
Otherwise, you might notice a syslog message like:
procmail: Enforcing stricter permissions on "/var/mail/sjk"
when it chmod's the file to 600. As you've discovered, this is
inconsistent with the SYSV (Solaris 2 anyway) default mailbox
protection of 660, gid=6 (mail). I think that's an OS-dependent bug,
with the `chmod u+x ...' as the workaround.
20.7 Changing mbox permission during compilation to 660
...it appears that mail that procmail delivers back into the
spool it is writing out with owner.group user.mail and rights
600. To me this is reasonable. Mail delivered to the spool by
/bin/mail is written out owner user, group mail 660.
When procmail delivers mail 600 later attempts at delivery with
procmail removed from the .forward file fail: /bin/mail doesn't
have permissions (or refuses to uses its permissions).
Since we have fickle and unruly users who will be moving their
.forwards in and out of place this is a problem.
Is the correct solution to force procmail to write 660? If so, how
is this done? I assume in the section of config.h just below the
warning about only messing with a section if you think you know
what you are doing. I don't like feel like I know well enough what
I'm doing to walk into that territory without some guidance.
[alan] I used to be the manager of the system support in the
College of Engineering, at the University of California, Santa
Barbara.
We supported about 1500 users from two HP 9000 G30's, using one of
them as the centralized mailer. Mail was available via NFS exported
/usr/spool/mail to over 200 workstations, of all kinds: SGI, HP,
Sun, etc.
We replaced /bin/mail with procmail as the local mailer (Mlocal)
because procmail correctly avoided NFS-locking problems, and it
supported user-configurable mail filtering, without compromising
system security.
In over two years subsequent to the change, we had no loss of mail
due to procmail being used as the local mailer. If you wish further
comment from the current system managers, send email to
"postmaster@eci.ucsb.edu".
To answer your specific questions:
* you can configure the permissions directly, by changing one of the
following defines in config.h:
/* bit set on mailboxes when mail arrived */
#define UPDATE_MASK S_IXOTH
/* if found set */
#define OVERRIDE_MASK (S_IXUSR|S_ISUID|S_ISGID|S_ISVTX)
/* the permissions on the mailbox will be left untouched */
#define INIT_UMASK (S_IRWXG|S_IRWXO) /* == 077 */
#define GROUPW_UMASK (INIT_UMASK&~S_IRWXG) /* == 007 */
We did not find it necessary, however:
o We did disable all locking except dot-locking, since the kernel
locks were the source of the NFS-locking problems. There have
continued to be occasional locking problems, but these are
"victim"-induced problems caused by using non-supported and
discouraged mailers, such as "mailtool" from older Suns. These
locking problems have nothing to do with mail delivery, but from
the mail client using kernel-advisory locks, and then orphaning
them or, leaving them locked all day long.
o An alternative to having users use .forward files, is to create a
file of users who would like to use procmail as their local
delivery agent, and use this file to initialize a class
variable.
Write a special rule in sendmail.cf which delivers mail using
Mprocmail instead of Mlocal when the destination user is in the
special procmail user class.
This allows users who want procmail-direct delivery in spite of
management worrying.
I set this up to test procmail delivery on our system before
changing Mlocal to use procmail. We placed some "volunteer" users in
the procmail class file, and they never had any problems (I was one
of them).
20.8 The .forward file must be real file
...I tried to make a softlink to ~/.forward, but then my
procmail wouldn't run. When I made a real ~/.forward file, then it
worked again. My question is -- why would procmail treat a link to a
file any differently than the actual file itself?
ln -s ~/.procmail/forward ~/.forward
[Werner Reisberger ] That's not a problem with
procmail, this is an MTA issue. Due to security reasons sendmail will
not deliver mail to files whicharesymlinks.
[david] procmail has restrictions on what permissions it will tolerate
on an rcfile. For example (I'm just guessing here) it can tell whether
it can read the target file but it cannot tell who might be able to
write to it. This prevents a major security hole
You can make hard link to the file, since A hard link is completely
indistinguishable from the original file. But note: a file hard-linked
to two or more names is very distinguishable from a file with only one
(hard) link, and procmail, for example, will not deliver to a plain
folder that has two or more hard links.
You can also put the real file at ~/.forward and let
~/.procmail/forward be a symlink to
[< mikk0022@maroon.tc.umn.edu>] I suppose, the reasoning behind
procmail's folder policy is that procmail locks the file by name, not
inode. Hence it cannot guarantee mutual exclusion for access to a file
which has multiple names.
My understanding of the .forward policy is that a symlink need not
share the permissions of its target. Therefore somebody's .forward
symlink could have proper permissions, while its target could be
writable by others. This would allow anybody with the write
permissions to execute any program (potentially) from the user's
.forward file.
Two hard links share the same permission, so this argument doesn't
hold.
20.9 Using .forward if procmail already is LDA
[Elie Rosenblum ] If you have a .forward, it is
used by sendmail to replace a call to the LDA for the user in
question. So if you have a .forward that doesn't call procmail,
procmail is ...
[david] Elie sent the answer to me with a carbon to the list, but
since reading my personal copy my inbox got trashed. As of this
writing the list copy hasn't reached me, but the rest of that
sentence (as I recall from reading it before it got hosed) was to
the effect that procmail is then never invoked at all on your
incoming mail; a .forward takes precedence over the LDA. That
scenario never occurred to me. Thank you for explaining.
[Philip] Scratch the bit about /etc/procmailrcs/$LOGNAME. You're
mixing up procmail -d with procmail -m.
Ah, got it ... after rereading the man page. The part about
/etc/procmailrcs really can apply only when procmail is setuid
root, so again it's something I've no experience with and never
quite followed or retained. So no file in /etc/procmailrcs is ever
used implicitly, but /etc/procmailrc can be.
[Philip] $HOME/.forward is handled by sendmail. If you have a
.forward, then sendmail rewrites attempts to deliver to you into
attempts to deliver to the addresses listed in the .forward file.
Or in other words, the .forward takes precedence over the LDA.
Thank you both.
20.10 Mail should be put in the mailqueue if write fails
...We want to deliver directly to a user's home
directory. But this can of course be temporarily full. Then the
mail should _not_ bounce, but instead be put back in the
mailqueue and tried again until either it succeeds or sendmail
bounces it after 5 days (as usual). The README file says this is
my choice (to bounce or not), but I cannot find any place where
I can set this. What is the correct place to set this behaviour
[1998-06-24 PM-L phil] The -t flag causes procmail to
return EX_TEMPFAIL where it normally would have returned
EX_CANTCREAT. If you've made procmail the local delivery agent then
you should add -t to the A= define, _before_ the -d flag.
20.11 Qmail: how to make it work with procmail
[1998-11-10 PM-L John Conover ] All you
do is install fastforward and dot-forward, (they are optional, and
are not required.) Then cp /var/qmail/boot/proc or
/var/qmail/boot/proc+df, to /var/qmail/rc.
[1998-11-10 PM-L Greg Boes ] From the qmail
FAQ (4.4 How do I use procmail with qmail?) Put
| preline procmail
into ~/.qmail. You'll have to use a full path for procmail unless
procmail in in the system's startup PATH. Note that procmail will
try to deliver to /var/spool/mail/$USER by default; to change this,
see INSTALL.mbox.
if you are trying to get procmail to deliver to maildir format as
well, take a look at rhi for patches:
http://www.qcc.sk.ca/~bguenter/distrib/procmail-maildir/
20.12 Qmail: Procmail looks file from /var/spool/mail only
...Procmail seems to want to do something in /var/spool/mail. But
since I use qmail, I don't have a /var/spool/mail. Is there a way
to have procmail not to create temp stuff there?
[philip] Get procmail 3.11pre7 and uncomment and and correct for your
local setup the MAILSPOOLHOME="/.mail" define in src/authenticate.c.
Compile and install. t's relative to the user's home directory.
Thus the name `MAILSPOOLHOME'.
[Ekkehard Knopp ] On the www.qmail.org page is a
patch that lets procmail 3.11pre7 work with Maildir's, (qmail's NFS
safe delivery format), and not must Mailbox's.
Very useful. Really slows down delivery though. On my test box,
just adding procmail to the delivery where all it did was deliver
to the default mailbox, and no other rules whacked my speed test
from something like 600,000 messages/day to about 180,000.
Killer. I suspect Procmail's locking of the Maildir 8 ways from
Sunday is probably partially to blame.
20.14 AFS: How to use Procmail when HOME is in AFS cell
...I've viewed some of the archived posts concerning AFS and
procmail, but each seems to have a different perspective on the
subject. Besides the fact that AFS isn't the greatest product in
the world, does everyone agree that it is not possible to use
procmail when your $HOME lies in an AFS cell? Mail sent locally
seems to work with procmail, but mail from users w/o a token or
AFS id just gets delivered to /var/spool/mail/someone.
[Christopher Lindsey 1998-03-09 PM-L] AFS
is awesome! You just have to treat it nicely. :) The only viable
solution that we've been able to come up with involves patching the
procmail-3.11pre7 sources to "fake" user home directories out of
another directory.
For example, my home directory in AFS is
/afs/ncsa.uiuc.edu/.u1/lindsey/
It is kept as such on the mail server in /etc/passwd as well.
However, we have some space set up via NFS in /var/forward with
space for each individual user (so /var/forward/lindsey in my
case).
The procmail patch intercepts requests for the user's home
directory and replaces it with the "fake" directory (the
/var/forward one). So for all practical purposes, procmail things
that my home directory is /var/forward/lindsey, and everything
works fine.
20.15 Help, some idiot sent my address to 30 mailing lists
You can make a procmail recipe to junk incoming mail from the
lists until you get the unsubscribe messages delivered to cancel
your participation. You should complain to the list's maintainer
that such things was even possible: The mailing list should have
sent you a confirmation message with unique "participate ID number"
that you need to send back in order for the subscription to take in effect.
KILL_FILE = $PMSRC/.kill-immediately
:0
*$ ? $IS_READABLE $KILL_FILE
{
KILL = `cat $KILL_FILE`
}
# 1) Make sure KILL has value
# 2) if match is found from header.
# 3) /dev/null does not need lockfile
:0
* KILL ?? [a-z]
*$ $KILL
/dev/null
[sean] ...In the long haul, your best bet with dealing with this
problem is to stamp out the offender - bring this harassment to
the attention of their ISP and get their account closed. Repeat as
necessary. Most of the mailing lists should have some record of the
submission request. Even if forged, the abuser probably has their
IP address in the headers somewhere (and if the person is actively
subscribing your friend to so many lists and actually WORKING at
covering their tracks, apparently you've REALLY crossed them). Most
people who stoop to these immature harassment tactics aren't
bright enough to fully cover their tracks.
Another alternative to having to manually deal with unsubs on
certain lists is once you've identified filterable characteristics
of the lists, BOUNCE them. Most semi-intelligent listserv
implementations will unsub you if they get repeated bounces. Yea,
not nice to the listserv maintainer - but then, if perhaps they'd
implement a subscription verification system, it wouldn't have been
a problem to begin with.
:0
* condition
{
# may expose your .forward - but if you're bouncing lists,
# it probably doesn't matter much.
EXITCODE = 67
# save header for examination.
:0 h:
bounce.log
}
You've got a sticky situation. You can't simply ditch all
unrecognized mail - you need to be able to review potential refuse
first, and take action on anything which doesn't belong (because
you certainly don't want to continue getting the non-wanted lists
till the end of eternity - you should want to unsubscribe from them
to simplify your mail).
20.16 Help, Procmail beeps and prints to my console
...when messages get filtered through procmail I get a beep and
then first 10 lines or so are also sent to the console. I get a
lot of messages so the beeps, and stuff on my screen is getting
very annoying.
[sean] One or the other should do the trick (or both even): Go to
your login file (what it is named depends on the shell you're
using), and add:
biff -n
Or/also, in your .procmailrc add:
COMSAT = "no"
[manual] has information on the COMSAT variable. It also states
(contrary to reasoning I gave in above) that COMSAT defaults to
'no' if you specify an rc file on the commandline (otherwise, it is
on by default).
Doing this latter one should keep procmail from generating
COMSAT/BIFF notifications, but would still leave your shell capable
of receiving them, say, if you only processed certain mail in
procmail manually or somesuch. Personally, I turn biff off AND set
the COMSAT off. I read my mail when I read my mail, and I check it
often enough (with a POP client at that).
20.17 Help, procmail dumps mail to console
...I have installed sendmail and procmail on my linux machine
(latest version of slackware) it works ok, but procmail if run
with -d $u dumps all mail after receiving immediately on the
console with ---- more ---- I don't like it, a beep is ok, but I
do not want all the garbage on my screen. Is there a way to tell
procmail that I just want the mail in my mailbox
(/var/spool/mail/$u) ? Thanks for the help!
[Xavier Beaudouin ] Check your /etc/inetd.conf for a
in.comstat, add a '#' at the beginning of the line, save the file
and killall -HUP inetd. This should stop this ;-)
20.18 Help, corrupted From_ line in mailbox
[Jeffrey S. Gilton
1998-02-11 in procmail mailing list " Solved the FFrom problem"]
Thanks to everyone who responded to my questions about a problem where
the From line was getting corrupted. Here I tell what was the real
problem.
To recap, when our Caldera OpenLinux 1.1 system received multiple
email messages very quickly, some messages would get multiple F's on
the from line and then subsequent messages would be missing the F's.
Most responses said that it sounded like a file locking problem.
Suggested solutions were to get the latest version of procmail or
recompile our version so that it would look at the file locking
mechanisms.
The funny thing was that three systems with new installs didn't
exhibit the problem.
The file locking recommendation eventually led to the real problem. On
a good system I would run our spam script (we spammed ourselves to
trigger the problem) and everything would work. Using top I would see
multiple instances of procmail running. Looking at the directory where
the spool files were, I would see a spool_file.lock file get created
and then go away.
Finally, I did the exact same thing on the system that wouldn't work.
There I would see the multiple instances of procmail running but no
lock file being created. I said to myself "Now that I know what is
happening, the question is why."
It turned out to be a permission problem on the spool directory. On
the system that worked, the permissions were rwxrwxr-x with the owner
being root and the group being mail. On the system that didn't work,
the permissions were rwxr-xr-x with the owner and group being root.
This meant that procmail, which is run as mail couldn't write the
directory file. We changed the broken system to rwxrwxr-x with owner
root and group mail. The problem disappeared.
As I said, the suggestions about lock files were key. It guided our
investigation until we found the real problem. I thank everyone who
responded.
I've seen other posting about corruption of the From line. Perhaps you
have the same problem.
[Christopher B. Smith ] I had the exact same
problem with my upgraded OpenLinux system. For the record, if you are
running the imapd that comes with it, you should really set your
permissions for the directory is as follows:
chmod 1777 /var/mail/spool
I got that feedback from the guy who wrote imapd, and it works very
well.
20.19 Directing user's mail to HOME instead of /var/spool/
...I have a need to direct all a single user's mail to a mailbox in
his home directory, to $HOME/mailbox,
# One possible solution, not perfect
UHOME = /tmp_mnt/users
UHOME_LIST = "(login1|login2|login3)"
*$ ^TO\/$UHOME_LIST@
* MATCH ?? ()\/[^@]+
$UHOME/$MATCH
[era] Perhaps preferably use ^TO_ if you have Procmail 3.11pre7
or newer. This is the classical case of using Procmail where you
really need the envelope recipient information. The headers are
+not+ enough to determine who a message is for. If Procmail is your
MDA, you can have this, but I'd still think something involving
Sendmail would be more appropriate. For one thing, what if this
user would suddenly really want to use Procmail? You can set
`DEFAULT' and `ORGMAIL' for this one user in `/etc/procmailrc' to come
around that, but the bottom line, as so many times before, is that
Procmail might not be the right tool for this.
20.20 NFS mounting /var/mail is a good way to get bad performance
> /var/mail stays at a Solaris 2.5 machine. Cucipop is working
> at the same machine. It's fine there. But, I want to have
> more than one machine with cucipop and when I put cucipop at
> another machines, NFS clients, it is delaying more 30 or 40
> seconds to close the session.
[1998-06-23 PM-L Brad Knowles ] NFS mounting
/var/mail is a good way to get bad performance, especially when
you're doing any NFS writes. Even if you're not doing any NFS
writes, just having to deal with local file locking and trying to
translate that into NFS file locking is a nightmare (in general,
file locking is one of the single biggest problems left with NFS).
> Procmail is working good on NFS, it finishes quickly. But when
> cucipop is put on a NFS client, procmails starts to delay too.
Procmail probably isn't writing to NFS, or if it is, it's probably
not using the same locking mechanism as cucipop. Unfortunately,
each vendor and each program have their own ideas on how to best do
that.
[philip] cucipop was written by the author of procmail. Ideally,
when you compile cucipop you edit its config.h to use the locking
techniques that procmail's autoconf process determined for your
system(s). However, even if you didn't do that, cucipop uses the
same dotlocking algorithm as procmail.
Also, keep in mind that any POP3 server will have to copy the
mailbox in order to work on it, and many of them copy the mailbox
to /var/mail/.username (you got it -- creating lots of NFS writes).
When they're done, they copy the mailbox back to /var/mail/username
(after they copy any new mail messages that have come in to the end
of /var/mail/.username and locked then truncated the original
/var/mail/username file).
[philip] cucipop doesn't use a temporary file: it keeps it all in
memory. On deletes it updates the mailspool in place which should
never _lose_ data, though if the server crashes in the middle of
this you can end up with one or more bogus messages.
This is a *real* nightmare when you start talking about users who
select "Leave mail on server" and have multi-megabyte mailboxes.
[philip] Assuming you have enough memory, cucipop should be pretty
fast.
I think maybe now you're starting to understand why POP3 really
doesn't scale well at all in multi-machine environments (unless
you've cooked up a custom mail store that uses a real database
back-end, like Oracle Parallel Server), with /bin/mail (or
procmail) as a writable interface to this message store and POP3
and/or IMAP as a readable (and writable) interface to this same
message store. Then you can let the database vendors deal with the
hard data replication and distribution problems.
Otherwise, it's a pain-in-the-ass.
> Is there another good pop server?
Have you tried QPopper from Qualcomm? It's the single best POP3
server I've ever run across, although I wouldn't put even it in an
NFS write environment.
BTW, I used to be the Mail Systems Administrator for GNN (Global
Network Navigator), the web site/National ISP co-operative between
O'Reilly & Assoc. and AOL. At our peak, we had hundreds of
thousands of registered users, of which up to five to six thousand
were logged in at any one time, with their MUA set to check their
mail every minute.
We had a single primary Mail/POP3 server machine (Dec Alpha 2100 w/
four 250Mhz processors, 4GB RAM, 28GB hardware mirrored/striped
mail spool), and one warm spare (same CPU/RAM configuration,
physically hooked up to the same disks, but through DECsafe ASE not
mounting them unless the primary died).
20.21 I can't see the sendmail's response in LOGFILE
...As the man page says, this should've written to my LOGFILE. It
didn't. But it DID activate the pipe in the recipe. So what's up
here?
:0 hc
*$ ? $IS_EXIST $HOME/.vacation
| LOG=| ($FORMAIL -r; echo $IM_NOT_HERE) | $SENDMAIL -t
[david] The man page says that a variable capture recipe assigns the
standard output of the command to the variable. Since you are repiping
the output of formail and echo to sendmail, sendmail sucks up the
standard output of formail and sendmail. Sendmail itself does not
write to standard output, so the stdout of ( $FORMAIL -r ; echo
$IM_NOT_HERE ) | $SENDMAIL -t is nothing.
Thus you're assigning a null string to $LOG, and when procmail writes
$LOG to the logfile you can't see a difference.
20.22 Compiling procmail and choosing locking scheme
General advice: Everything except dot locking is usually broken.
[stephen, <199607292139.XAA12433@hera.cuci.nl>]. Remove fcntl() and
lockf(), only allow flock() (or omit it completely) Kernel locks
don't work. But that's all some programs use. Across a networked
filesystem, lockf() doesn't work, fcntl() and flock() should, but
they don't either because the lockd is buggy. Mailtool uses fcntl()
but does it wrong, so that's another problem. The only thing that
works on all platforms, all networks, all the time are .lock files.
Makefile refers to:
# Uncomment (and change) if you think you know
#LOCKINGTEST=100
# it better than the autoconf lockingtests.
# This will cause the lockingtests to be hotwired.
# 100 to enable fcntl()
# 010 to enable lockf()
# 001 to enable flock()
# Or them together to get the desired combination.
config.h refers to:
/*#define NO_fcntl_LOCK uncomment any of these three if you */
/*#define NO_lockf_LOCK definitely do not want procmail to make */
/*#define NO_flock_LOCK use of those kernel-locking methods */
20.23 Forwarding lot of mail causes heavy load
...There are several forward (e.g. ! walter@localhost) recipes
For every forwarded mail, a distinct sendmail process is created.
This leads to a heavy (IMHO unbearable) system load. How can I
stop procmail from running a sendmail process for every mail
forwarded?
SUMMARY: Look at qmail, it's better than sendmail.
[era 1998-08-15 PM-L] (Blows dust off old underutilized Bat
Book/ORA sendmail book) Yeah, setting QueueFactor (q) and QueueLA
(x) to suitable values should do what you want. You need to have
load-balancing support compiled in, though; according to the Bat
Book, sendmail -d3.1 tells whether you have it or not. (Mine just
says getla:0 which I would imagine means I have the support but the
load average was below the cutoff level.
AFAIK using load averaging would have the first messages
delivered and the rest queued. However, also not being a sendmail
guru, I do not know how to empty a sendmail queue for incoming
mail only. Moreover, even if I knew how to do this, it would have
to be done after procmail finishes.
[Liviu Daia ] Instruct sendmail to queue
messages when called from procmail:
SENDMAILFLAGS="-oi -od d"
then disable the normal sendmail daemon from your system init
scripts, and run it in flush queue mode only, that is, replace
/usr/sbin/sendmail -bd -q 15m
in your init scripts with
/usr/sbin/sendmail -q 15m
("15m" is how often the queue will be run (15 minutes).
Change it to whatever is appropriate
for your purposes). Also make sure to disable forking in your
sendmail.cf.
The downside of this approach is that it will also delay the
delivery of local messages.
Different approach: pipe messages to sendmail instead of using
'!' and use the wait flag. Something along the lines of:
:0 w
* conditions
| $SENDMAIL $SENDMAILFLAGS
Well, I'm actually not sure you can use the 'w' flag without 'f'
(the manual doesn't say it, and I'm not too familiar with procmail
internals), so if that doesn't work you might also try Sendmail
will rewrite the `From_' header (which you can probably safely
ignore), and it will (optionally) add a `From:' if one doesn't
exist, but it won't touch an _existing_ `From:'. Well, actually it
will encode or decode any 8-bit characters in the `From:' according
to the options in sendmail.cf, but it won't change the _meaning_ of
the "From:". In fact, that's exactly what procmail does too in the
'!' recipes.
:0 fw
* conditions
| $SENDMAIL $SENDMAILFLAGS
# dummy recipe to stop procmail from delivering an empty message
:0
a /dev/null
20.24 What happens to mail if MDA Procmail fails
...When procmail is the local mailing agent distributing
e-mail to a user's $HOME and the target machine is 'down', where
does the e-mail go? I was given the impression that the mail
would be collected on the 'mailhub' in /usr/mail/BOGUS.xxx
(Solaris system). It is not happening and we have the potential
of losing mail.
[philip] I assume that by "target machine" you mean the NFS
server for the given user's account. Procmail's attempt to read
~/.procmailrc will timeout, then when it tries to write to $DEFAULT
(which you say is in their home directory) it'll time out (again)
and return EX_CANTCREAT to sendmail. Sendmail will then presumably
bounce the message.
Now, if sendmail is looking for .forward files in user home
directories, then procmail will never be called, as sendmail will
try to open the .forward file and consider it a transient error
when it times out, causing the message to be queued for a later
delivery attempt.
(Note: invoking procmail with the -t flag causes it to return
EX_TEMPFAIL instead of EX_CANTCREAT. This would cause the message
to be requeued. However, this is not generally recommended.)
20.25 Procmail reads entire 90Mb message into memory
...last week my workstation ground to a halt when procmail received a
90Mb Email message (ran out of memory). The point is, such
message sizes are fine by me, as long as the system can handle
it. Is there any way I could make procmail only read the headers
of that message before scanning /etc/procmailrc/ ~/.procmailrc and
acting on it? That way it wouldn't need to read the entire
message into memory.
...Recently, I modified the sendmail.cf file to pipe messages
through procmail before sending them to deliver, so that I can
use system-wide procmail recipes for spam filtering. However,
yesterday we had a client send a 22 megabyte e-mail message (on
purpose, no less) and the system just came to its knees trying to
deliver it to the user's mailbox.
[philip] Btw, All the versions of /bin/mail (or mail.local) that
I've seen the source for either read the entire message into memory
first or use a temp file. Depending on where temp files are
located, a 90MB temp file may be just as bad as holding it in
memory.
And, No, there isn't. Hacking it in would not be non-trivial, mainly
because the current code runs with the assumption that the entire
message is there, and determining when it actually needs to see the
entire body (to do demand loading) would not be easy. Remember
that a condition on the size of the message, ala
:0
* > 10000000
/dev/null
would require the body to be read... It really is just better to
simply have sendmail enforce the limit. You should be doing it
there anyway to cut down on the totally trivial denial-of-service
attacks and because it's more efficient.
...I am running procmail ver 3.11pre7 and I keep getting "out of memory
as i tried to allocate 8xxxxxx bytes.". I have over 100 meg
available swap space so i have a difficult time understanding
this. Is this a known error?
Procmail's memory allocation technique appears to non-optimal for
some OS/libc combos, namely implementation of the libc system
function realloc() (FreeBSD has been reported). It's conceivable
that the configuration process could be enhanced to detect this
system limitation to use a strategy more efficient on them. Don't
hold your breath.
[ed] There is a patch available that should fix the problem
for you. See the messages at
.
20.26 Help, procmail uses occasionally huge chunk of memory
...we've noticed that occasionally, procmail uses a huge chunk of
memory. It's always the same 17MB as reported by the top command.
Can anyone enlighten me as to why sometimes procmail creates such
a huge footprint and other times doesn't, for the same user with
an unchanged .procmailrc file?
[ed] Is your operating system a BSD variant such as FreeBSD or
OpenBSD? If so, then the problem is due to a poor implementation of
the Standard C Library system function realloc() on those
platforms. A patch that works around this is available. See the
messages at
Specifically, the patch is located at
.
It's an artifact of procmail's memory management. It reads
an entire message into memory before working on it. Fear the system
with procmail as the local delivery agent, where people are
slagging 100M CAD files around. :-)
20.27 Procmail signalled out of memory in my verbose log
...I notice in my procmail verbose log the following
'transaction':
procmail: [10239] Sat Jan 9 08:49:02 1999
procmail: Out of memory
buffer 0: "formail"
buffer 1: " formail -A "X-Check: List""
Folder: **Bounced** 5744
procmail: Notified comsat: "bhoule@:**Bounced**"
If I act quick enough when this happens, I can look in
spool/mqueue and find a message with a gazillion addresses in the
To: line. So it seems that formail is having trouble adding my
X-Check header to an already large set of headers.
[philip] No, it's procmail that's unable to allocate enough memory.
The buffer dumps indicate that procmail was unable to get enough
memory somewhere between parsing the action line and reaching the
next recipe -- buffer 0 would not contain the string "formail" if
procmail had gotten to another recipe or variable assignment.
What's weird is that the message is so small (only 5744 bytes
according to procmail). Do you only see this error on this recipe,
or at random places in your .procmailrc? If the later, then I would
guess that your mailserver is running out of memory for some other
reason and that procmail happens to be an innocent bystander. If
the former, then, well, I'm not sure.
The message is never delivered to me. Is there anything I can do
so that procmail/formail will act as if it was never there so the
incoming dumps into my inbox rather than returning an error to
the mailer? This "**Bounced**" business is not a very helpful
action.
Giving procmail the -t flag will cause fatal internal errors that
are normally returned as permanent errors to be returned as
temporary failures instead. Otherwise there's no way to control
that. (Setting EXITCODE won't work because procmail needs to malloc
memory to handle TRAP and EXITCODE, and it'll refuse to try that
when it was malloc that caused the exit.)
20.28 Variables DEFAULT and ORGMAIL
...According to the man pages, `DEFAULT' is defined as `ORGMAIL'
...so if I redefine ORGMAIL, then `DEFAULT' should change as
well, which doesn't help me. Any help on this would be
appreciated
[david] `DEFAULT' is initially defined as equal to `ORGMAIL'. Once
procmail has started reading /etc/procmailrc (if it is the MDA) or
your .procmailrc, you can change the value of either without affecting
the other.
In fact, you can even set DEFAULT on the command line when you invoke
procmail (I'm not sure about doing that with `ORGMAIL', though), and
that value will override its normal initial value equal to `ORGMAIL'.
What if it is possible that dropping to DEFAULT fails due to disk full?
Then you would better have another drop place in another file system.
Peek at bdf(1) or df(1) to find out the different mounted file systems.
# Place this to the end of your .procmailrc and define
# DEFAULT_SECONDARY
:0 :
$DEFAULT
:0 E
$DEFAULT_SECONDARY
If you deliver explicitly to $DEFAULT, procmail treats it like any
other save-to-folder recipe, and if the write fails, it continues
reading recipes.
...If I had set the "deliver" destination as `ORGMAIL' rather than
`DEFAULT,' would it have made any difference?
Nope. If you write a recipe for it, procmail just expands the variable
and doesn't give a heck if it happens to be the same destination as
`DEFAULT' or `ORGMAIL'. `DEFAULT' is special to procmail only when it
uses it on its own after falling off the end of the rcfile; `ORGMAIL'
is special only at startup (without -m) and when procmail falls off
the end of the rcfile and finds that it cannot save the message to
`DEFAULT'.
In general, if procmail falls off the end of the rcfile,
fails to save to `DEFAULT', and then fails to save to `ORGMAIL',
does it revert to the compiled-in value of `ORGMAIL' ?
[philip] Procmail has no fallback beyond the current value of
`ORGMAIL'. If delivery to both `DEFAULT' and `ORGMAIL' fail, then
procmail gives up and exits with error code 73 (EX_CANTCREAT) or 75
(EX_TEMPFAIL), depending on whether the -t flag was given. Setting
`EXITCODE' would probably override those. The message is logged
as "*Bounced*".
20.29 When DEFAULT cannot be mailed to
If procmail gets to the end of the rcfile without delivery (or without
being directed to another rcfile by an INCLUDERC or HOST assignment),
it assumes these:
:0:
$DEFAULT
:0 e:
$ORGMAIL
That is, it tries to deliver to $DEFAULT and if it can't, it tries
$ORGMAIL. If that fails too ("deep, deep trouble" as Stephen says in
the man page), it exits without delivery and reports failure to the
MTA, which, depending on other factors, will either requeue the letter
and try delivering later or will bounce it to the sender.
20.30 Variable DROPPRIVS
...I have procmail invoked from a mailtable for a virtual domain.
Presently that runs as root, inherited from sendmail. I'd like to
have it run less privileged. I tried chown'ing the rc file to the
user I want used and setting "DROPPRIVS=yes". That didn't do it.
So I added "LOGNAME=user" and "USER=$LOGNAME" before the
DROPPRIVS assignment and that didn't work.
[philip] DROPPRIVS only has an effect inside the /etc/procmailrc used
when procmail is running in delivery mode (-d), not when it's
running in mailfilter mode (-m). USER and LOGNAME have no effect on
the working of DROPPRIVS, as procmail is just going to change to
the uid/gid of the user specified on the command line after the -d.
Your mailtable entry should be specifying the procmail mailer,
which runs procmail in mailfilter mode.
If the following are true:
o procmail is running in mailfilter mode
o no assignments were given on the command line
o the -p flag was not specified
o the rcfile specified is located under /etc/procmailrcs/ without
backwards references ("/../"s)
o the rcfile is not a directory (duh!)
then procmail will assume the uid and gid of the owner of the
rcfile. If the rcfile is actually a symlink, the procmail will
assume the uid and gid of the link itself, not the underlying file.
If your OS allows anyone to give away ownership of files with
chown, the procmail adds the following restriction to those above:
/etc/procmailrcs must be owned by root and mode 700.
20.31 Variable HOME
[david] Since procmail doesn't understand tilde, you have to use
variable HOME instead.
CONTENT = `cat ~/file.txt` # Won't work
CONTENT = `cat $HOME/file.txt` # ok
But accessing other user's home is another story. You could change
the SHELL temporarily to get procmail understand the reference,
like this:
SHELL = /bin/csh
CONTENT = `cat ~user/file.txt`
SHELL = /bin/sh # restore original setting
Because the tilde is in $SHELLMETAS, when procmail sees a tilde,
it will invoke a shell. It's better to skip the extra process of a
shell and use the $HOME variable: put a symlink somewhere under
your own home directory that points to the other user's file so
that you can use the $HOME variable in your .procmailrc and avoid
the shell invocation.
However, there are dangers on this too, because sysadm may move
home directories and your symlinks may be out of date. If you
expect such changes and broken links, then you could cache the
needed home directories at time you need them:
HOME_PHIL = `ksh -c "echo ~phil"`
HOME_ED = `ksh -c "echo ~ed"`
20.32 Variable HOST
[philip] If a assignment to the "HOST" variable occurs where the
assigned value doesn't equal the hostname of the machine on which
procmail is running, procmail will stop reading the procmailrc, and
if there are other procmailrcs specified on the command line, it
will start reading them.
[david] It goes back to the early days of procmail, before Stephen
thought of INCLUDERC or the "var ?? condition" syntax. When people
had to use different code based on which local host machine was
processing a particular message, the method was to list a number of
rcfiles on procmail's command line. The first one would start out
with general code for all messages and all hosts and then have a
HOST = some.specific.machine
assignment, followed by code for mail delivered on that machine.
If the first nine characters of "some.specific.machine" matched the
real value of $HOST, procmail would stay in that rcfile; on a
mismatch, it would jump to the second rcfile named on the command
line.
The second rcfile would probably be for another particular machine,
so (unless it first had some universal code for all machines except
the first one, or unless there were only two machines where
procmail might run) right at the top it would have
HOST = this.specific.machine
Again, a match for the first nine characters would keep procmail
reading this rcfile, but a mismatch would make it jump to the next
rcfile.
And so it went. An incorrect HOST assignment (note that "HOST"
alone attempts to unset the variable, so it is *always* an
incorrect assignment) in the last rcfile on the command line made
procmail drop the message and exit. Since we almost never name
more than one rcfile on the command line now, attempting to unset
HOST in .procmailrc will have that effect.
I would guess that the only use of this original setup still around
is in SmartList, where flist invokes procmail with a number of
rcfiles on the command line and uses things like
HOST=go.to.the.next.rcfile.now to move from one to the next. Also,
procmail's -m facility (which didn't exist back then) is
incompatible with using HOST to jump among rcfiles, because it
requires naming exactly one rcfile on the command line.
Nowadays we can do something like this to use different rcfiles on
different hosts:
:0
* HOST ?? ^^\/[^.]+
{
INCLUDERC = $HOME/.$MATCH.rc
}
20.33 Variable LINEBUF
...[manual] Length of the internal line buffers, cannot be set
smaller than 128. All lines read from the rcfile should not
exceed $LINEBUF characters before and after expansion. If not
specified, it defaults to 2048. This limit, of course, does not
apply to the mail itself...
_Note:_ Beware of simply setting LINEBUF to a huge value: such an
assignment causes procmail to immeadiately allocate twice that much
memory (procmail has two buffer internally of size $LINEBUF).
[philip] Those 160 lines of condition are almost certainly
overflowing LINEBUF. You should either a) use one of the
innumerable recipes sent to the list demonstrating the use of
fgrep; b) break it into multiple recipes; or c) increase LINEBUF.
If you modify this list of domains regularly, then you should
strongly consider (a), as (b) and (c) just put off it happening
again.
`LINEBUF' only applies to lines from procmailrcs. You generally only
have to worry about `LINEBUF' when you have a variable expansion or
command expansion (backquotes) that doesn't have an obvious and
reasonable bound on its size. procmail will avoid overrunning its
`LINEBUF' length buffer when doing command expansions by ignoring the
extra output, so you're safe there, as long as data truncation is
fine. Variable expansion isn't checked like that, so you can cause
procmail to coredump by doing something like:
:0
* ^Subject: \/.*
|some-program $MATCH
then feeding procmail a message with a huge Subject: header field:
since no shell meta characters appear in the action, the action
line will be expanded and exec()ed by procmail directly instead of
by the shell. On the other hand, the following is fine:
:0
* ^Subject: \/.*
|some-program $MATCH ; ;
The semicolon forces a shell invocation, and the shell should be
safe. If your /bin/sh can buffer overrun on variable expansion, then
you're in more trouble than you know.
Action lines aren't the only place to watch your variable
expansions. Variable assignments and condition lines that have a
leading dollar sign also undergo expansion. For example, this isn't
safe:
SUBJECT = `$FORMAIL -x Subject:`
NEWSUBJ = "Subject: $SUBJECT"
procmail won't buffer overrun in the first line, but a really long
subject could cause the second to do so. The following should be
safe:
NEWSUBJ = "Subject: `$FORMAIL -x Subject:`"
but even then only if you're sure the shell is doing the expansion
of NEWSUBJ.
Note that matching against the value of a variable (using the "var
??" condition special) is safe no matter what the size of the
contents of the variable. The problem is when you interpolate the
variable into something else.
Is there any easy way to know default LINEBUF value for
specific procmail? I'm sure there's a much easier way, but this
will work:
# Mitsuru Furukawa
#
$OUT = $HOME/tmp/linebuf.lst
:0 wc: $OUT$LOCKEXT
*$ ! ? $IS_EXIST $OUT
| echo "$LINEBUF" > $OUT
[philip] If you examine the procmailrc manpage, you'll note that it
lists fourteen variables (among them DEFAULT but not LINEBUF) whose
values are reset in the environment by procmail, plus some
additional ones like IFS, ENV, PWD, and PATH which come out of the
top of config.h. Following this is a list of all of procmail's
magic variables, including those fourteen. The idea is that while
procmail has thirty magic variables, only fourteen of them are put
into the environment by procmail.
The others may have default values, but they're 'input only': if
what you're doing depends on one of the others having a certain
value, then you should just go ahead and set it to that value. I
know of only two ways to find out what value procmail is using by
default: a) check the manpage (the manpages should show the correct
default for the machine), or b) fire up your favourite debugger and
hope that no one stripped the procmail binary.
There will be no error message when Procmail dumps core, even
though the reason is apparently precisely that `LINEBUF' is being
exceeded too much.
Is there a limit on the length of a single line
[david] Yes, both before and after variable expansion and
command substitution, it must be shorter than `LINEBUF' characters.
The exceptions are (1) comments and (2) commands that are run by a
shell rather than directly by procmail. The entire condition must
be under `LINEBUF' characters
Unfortunately, LINEBUF seems to be a write-only variable; you can
change its value but you can't find out its current setting.
20.34 Variable LOG and LOGFILE
If you want to print something to the `LOGFILE', you could do it
like this
LOG = " This message goes to LOGFILE"
LOG = " $NL$NL And this has linefeeds around $NL$NL"
Or like this, which proves to have some nice feature in respect to
`VERBOSE' setting:
dummy = " This message goes to LOGFILE"
dummy = " $NL$NL And this has linefeeds around $NL$NL"
You see, if you set `VERBOSE="off"' Then the `dummy' lines are not
printed and recorded to the `LOGFILE'. `LOG' messages are aways
printed, and that's not very nice if you're trying to suppress
messages while you call some subroutine:
saved = $VERBOSE
VERBOSE = "off"
# Hope this subroutine does not use LOG
# Eg. $PMSRC/pm-jaaddr.rc
INCLUDERC = $RC_ADDR
VERBOSE = $saved # restore original value
20.35 Variable TRAP
Here is one example how to write to the logfile, Be sure that you
have preset all the variables, this just demonstrated the usage of
`TRAP'. Pay attention to right use of single and double quotes if
you pass the values to the shell. Like in this example where the
`/dev/' is removed from the `FOLDER' variable's value.
TRAP = 'echo "
FROM $FROM
TO/CC $TO / $CC
SUBJECT $SUBJECT
FOLDER $LASTFOLDER
" | sed -e "s#FOLDER /dev/#FOLDER #g"'
And if your MUA expects the file to be touched before it sees new
incoming mail, here is recipe by [david]:
TRAP = 'touch -m $HOME/Mail/$LASTFOLDER' # with strong quotes
Place it early in your rcfile; then each recipe that saves to a
directory can look simply like this, and the trap will take care of
the touching:
:0 flags # no local lockfile needed for save to directory
* conditions
directoryname/.
[david] Procmail terminates when it exits ... after final delivery
of the message. It doesn't terminate (nor execute TRAP) after
delivering a copy to a `c' recipe [however, a clone does execute
TRAP when it terminates, unless you unset TRAP for it]. It doesn't
execute the trap after a variable assignment, a variable capture
recipe, a filtering recipe, nor any other non-delivering action.
On the other hand, it *does* execute the trap if you do a quick
bail-out by unsetting or missetting $HOST.
[Recipe to record Subject lines on exit]
<> [david] ...this will
list all subject lines in the logfile upon exit if there are two
or more. The earliest would appear twice: once in the trap output
and once in the logabstract.
:0
* ^Subject:.*$(.+$)*Subject:
{
# If there is already `TRAP' set, combine the
# old trap recipe with this
TRAP = "${TRAP:+$TRAP ; }$FORMAIL -XSubject:"
}
20.36 Variable UMASK
There is a better way to find out which folders contain new
mails if you are using procmail to filter the mails. (This was a
hack by one of my friends) procmail allows you to set UMASK on the
folders. So before doing anything, set UMASK to 076, which means the
perms will be -rwx-----x to any folder which receives mails. now
using `find' -perm -001, you can print the folders which have new
mails. the shell script which does this will also have to chmod o-x
on all these folders.
...How does this work? AFAIK umask only applies to new files created
and not to appending to existing files which is what procmail
essentially does, right?
[era] Procmail does interpret UMASK this way, so this works,
but I don't think it's a particularly good solution. It's actually
hinted at in the documentation for UMASK in procmailrc(5). `find' is
a rather heavy program to start up every time you want to look for
mail. (Haven't done any timings, though.)
o I just grep -c '^From ' on my mail folders to see how many
messages there are in them. (This is only an approximation, in
the case where one or more messages contain unescaped From_
lines.)
o For a really pedestrian solution, keep all your spool files in
their own directory (I think this is a good idea for other
reasons as well) and do an ls -lrt on that directory, possibly
piped into a sed script to trim off files with timestamps older
than, say, 24 hours.
o If your mail reader will reset permissions on spool files when
it gets mail from them, the UMASK trick is a good base for a
mail checking script, but I would then only ls -l the spool
files and look for files with an x01 permission.
20.37 UMASK and permissions
My mail folder says -rw-r--r-x, Is there a bug in Procmail's
umask handling? (see last x bit)
[philip] That's a feature, not a bug! To quote the procmailrc(5)
manpage:
_UMASK_: The name says it all (if it doesn't, then forget about
this one :-). Anything assigned to UMASK is taken as an octal
number. If not specified, the umask defaults to 077. If the umask
permits o+x, all the mailboxes procmail delivers to directly will
receive an o+x mode change. This can be used to check if new mail
arrived.
Anyhow, normally, under Unix, the create system call will set
default permissions of 666 and the umask can only be used to mask
off the bits you don't want (and not to e.g. add x bits).
Shouldn't Procmail work this way, too, just to be consistent with
the rest of the system?
creat() will set the permissions to whatever you want it to,
modulus the umask. If the umask is zero, you can set the
permissions to 7777, though that would be kind of stupid (and
actually, most versions of UNIX won't let you set both the sticky
bit and an executable bit unless you're root, for historical
reasons). Most programs that call creat() or open(..,O_CREAT,...)
give a mode argument of 0666, as they generally don't write out
executables. Procmail just happens to call open() with a mode
argument of 0667, to be modified by your umask.
20.38 Performance difference between backtick and "|" recipe
Procmail sends the whole message to stdin whenever
it sees backticks used. And if you use recipe, you can add
the `h' flag to feed only the header to the program, and not the
whole message. Let's ask academic question: Which one
of the choices below is efficient?
# Side effect: Do something with shell
dummy = `echo hi there > some-file.txt`
:0 hwic
| echo "hi there" > some-file.txt
Procmail sends whole message to first line and only headers
to second recipe. Answer: It doesn't matter. Either way procmail
will make one write system call which will return 0 [bytes written]
and off it goes. You should use the first one, because the latter
affects the `A' and `E' flags later, first one is more clear overall.
While someone suggested following, it was rejected because it
hurts performance more [stephen]. The cat process is useless and
directing to dev null does not buy anything.
:0 hwic
| cat - /dev/null; echo "hi there" > some-file.txt
20.39 Procmail's temporary file names while writing file out
...Any ideas what might make those .nfs* files? They contain
messages which seem to have been successfully processed by
procmail in the later parts of the .procmailrc . However, I doubt
they'd ever get cleaned up if I didn't discover them.
/disk3/home/foobar/Mail 119) ls -la backup
total 22
drwx------ 2 stanr 512 Nov 11 21:00 .
drwx------ 3 stanr 2560 Nov 11 21:11 ..
-rw------- 1 stanr 3063 Nov 4 03:31 .nfsA0c724.4
-rw------- 1 stanr 1780 Nov 3 23:00 .nfsA47da4.4
-rw------- 1 stanr 849 Nov 3 23:22 .nfsA481f4.4
-rw------- 1 stanr 2293 Nov 11 11:28 .nfsA737d4.4
-rw------- 1 stanr 2598 Nov 11 20:39 msg.HCJB
-rw------- 1 stanr 3127 Nov 11 21:00 msg.ICJB
-rw------- 1 stanr 1884 Nov 11 20:45 msg.KCJB
/disk3/home/stanr/Mail 120)
[david] procmail uses temporary name while it is trying to
write a file out, which it renames if things go well. I noticed
that they all came from a 4h 31 span overnight; perhaps there was
some systems work being done on your machine that screwed things
up?
:0 ic
| cd backup && rm -f dummy `ls -t msg.* .nfs* | sed -e 1,3d`
[aaron] When a file that is being used by a program on an NFS
client gets unlinked the NFS server renames it to something like
that. It should then actually get unlinked when the file is closed,
but it looks like the NFS server never got the close message for
those.
[Keith Pyle ] It is a result of using NFS, but
the fault lies with the operating system on the NFS client. Keep in
mind that NFS is stateless from the perspective of the NFS server.
It keeps no information on how any file is being used. So, if a
client tells the server to delete the file, the server deletes the
file. This is not normally a problem, but many programs use a
"trick" of Unix where the program opens a file, unlinks (deletes)
it, and then continues to use the file. For all local files, the
Unix kernel will not actually delete the file until all processes
which have the file open exit. This works very well for temporary
files.
If a client tells an NFS server to delete a file, it will delete
the file immediately because of the stateless nature of NFS. The
server has no way of knowing if any client still has the file open.
To avoid this problem, if a client unlinks an open file on an NFS
filesystem, the file is renamed to .nfs* where * is a unique value.
The NFS client system is supposed to delete the .nfs* file when the
process exits. However, there are some versions of Unix which do
not do this well (e.g., AIX). If one of these OS's is used, it is
common to find .nfs* files in various places. Therefore, it is a
good idea for system administrators to periodically purge any .nfs*
files over a certain age to eliminate the unsightly buildup in the
filesystems.
20.40 Parameter $@
[david] Of version 3.11pre7 procmail does not grok "$*", nor does
it grok "$@" outside a pipe or forward action. The only way to get
the positional parameters all quoted together into "$*" is
something like this:
This doesn't work after all
ARGS = `echo "$@"`
Procmail substitutes null for "$@" there. *This* works, though:
:0 ir
ARGS=|echo "$@"
After that you use "$ARGS" instead of "$*".
If you try to set ARGS with ARGS="$@", procmail doesn't substitute
for "$@" and makes $ARGS null. If you try ARGS="$*" you get the
literal text '$*'.
[philip] Of course, $ARGS differs greatly from $@ in that $ARGS will
either be split on whitespace (if unquoted) or one argument (if
double-quoted). $@ has the cool property that if double quoted
it'll still be split into multiple arguments on the original
argument boundaries. Since full-blown email addresses often have
spaces, this distinction should not be casually dismissed. Note
that while you might not type in such an addresses, your MUA's
reply builder may.
20.41 Procmail variables are null terminated (detecting null string)
You can't catch null in the message. Eg if you try like this
NUL=`/usr/5bin/echo "\000"`
:0 HB
* $ $\NUL
{
LOG = "Caught NUL"
}
[philip] It won't work as expected. The problem is that environment
variables (and therefore procmail variables) are null-terminated,
and therefore cannot contain a null. The above line creates an
empty variable. The solution is to use an inverted character class:
NUL = `/usr/5bin/echo '[^\001-\377]'`
Note that procmail handles 8-bit characters except for null in
procmailrcs, so you can use a literal control-A and octal-377 in
your .procmailrc and save an echo and shell invocation right there.
20.42 FROM_DAEMON TO and TO_ and case-sensitiveness
[david] ^TO is case-insensitive by default. Stephen once told me
something to the effect that tokens like ^TO, ^TO_, ^FROM_DAEMON,
and ^FROM_MAILER are *always* case-insensitive, even if the recipe
has the `D' flag, but I'm not positive that that was what he was
saying, and we never pursued it. Certainly they are insensitive to
case if there is no `D'.
[philip] If a regexp contains the ^FROM_DAEMON token, then that entire
regexp is treated as case-insensitive. Other conditions in the
recipe are not affected by this. The other tokens have no effect on
the case-sensitivity. (This is with procmail 3.11pre4)
20.43 TO_ macro deciphered
...What is the essential difference between TO and TO_ ?
[phil 1996-03-21] The difference is that ^TOalias1@site may match
something like bobs-alias1@site while ^TO_ won't.
[elijah 1997-09-16] Let's rewrite that in perl /x format. See
below. The definition of the word boundary in block (E). See below.
The ^TO_ expansion was added in v3.11pre4. You'll probably have to
just ^TO (no '_'), which should work almost as well.
/ # [begin regexp]
( # [Block (A)]
^ # Anchor to start of line
( # [Block (B)]
(Original-)? # Optionally proceed (C) with "Original-"
(Resent-)? # Optionally proceed (C) with "Resent-"
( # [Block (C)]
To # "To"
|Cc # or "Cc"
|Bcc # or "Bcc" {very rare in practice}
) # [end (C)]
| ( # [Block (D)]
X-Envelope # Proceed line 17 with "X-Envelope"
|Apparently # or "Apparently"
(-Resent)? # with optional "-Resent" appended
) # [end (D)]
-To # "-To" [line 14]
) # [end (B)]
: # ":"
( # [Block (E)]
.* # any text
# any single char other than letters, numbers,
[^-a-zA-Z0-9_.]
# hyphen (-), underscore (_), or period (.)
) # [end (E)]
? # Block (E) is optional
) # [end (A)]
/x # [end regexp]
20.44 TO_ macro and RFC 822
...According to RFC822 the From address can contains almost anything
and the valid email address can be extracted from the line as
long as it is enclosed between <...>. Like .
[by Vikas Agnihotri ] Block (E){see
TO_ macro explanation} is there to slurp up that part. The
is not needed, and a case such as:
From: "jester@fun.house"
Will confuse a test for "^TO_jester@". Yes, I have seen people do
that stuff, apparently not even maliciously. And although valid
following is also valid
From: someone@somewhere.com
[Elijah continues] it will also confuse the regexp. I don't like
the ^TO and ^TO_ macros for most things and typically use stuff
like this:
^(Resent-)?(To|CC):.*[< ]{address}([ >]|$)
It still can be confused, but the things that will cause problems
are fairly rare in practice. You might prefer something like this:
^(Resent-)?(To|CC):([^(]+([(].*[)])?)*[, <]{address}([, >]|$)
Which can correctly deal with
To: (hatter@tea.party) {address}
To: (fake {address}) bill.the.lizard@the.jury.box
To: Alice , "W. Rabbit (late)"
, Gentle Reader <{address}>
To: jabberwocky@vorpal.swords.r.us, duchess@the.croquet.game,
chesire@no.where, {address}, dinah@meow.org
It will still fail for
To: (fake <{address}>) mockturtle@tortoise.edu
If someone is malicious enough to send you such mail.
20.45 FROM_DAEMON deciphered
Here is the exploded FROM_DAEMON regexp as of 3.11pre7
(^(Precedence:.*(junk|bulk|list)
|To: Multiple recipients of
|(
((Resent-)?(From|Sender)|X-Envelope-From):|>?From )
([^>]*[^(.%@a-z0-9])?
(
Post(ma?(st(e?r)?|n)|office)
|(send)?Mail(er)?
|daemon
|m(mdf|ajordomo)
|n?uucp
|LIST(SERV|proc)
|NETSERV
|o(wner|ps)
|r(e(quest|sponse)|oot)
|b(ounce|bs\.smtp)
|echo
|mirror
|s(erv(ices?|er)
|mtp(error)?|ystem)
|A(
dmin(istrator)?
|MMGR
|utoanswer
)
)
( ([^).!:a-z0-9][-_a-z0-9]*)?
[%@> ][^<)]*(\(.*\).*)?
)?
$
([^>]|$)
)
)
[era] explains the last regexps as follows:
(([^).!:a-z0-9] End of e-mail address token
[-_a-z0-9] Another alpha token
)? ... or maybe not;
[%@>\t ] Address separator -- either or
or a bare address with whitespace
around it
[^<)]* Skip as long as we don't run into another
bracketed address or end of comment
(presumably to prevent this from matching
inside parenthesized comments in the first
place)
(\(.*\).*)? Skip optional parenthesized comments and
anything after them if found
)? ... or maybe not; maybe we just see an ...
$ ... end of line instead
([^>]|$) Uh, I should know what this is supposed to do,
but I can't quite remember what it's for. I
think it had something to do with continued
header lines ... Anyone?
Does ^FROM_MAILER match on the Return-Path: line?
[david 1998-04-29] Apparently not, but it does match on the UNIX
From_ line, which usually contains the same address as the
Return-Path: header.
Does anyone have an idea how I can use this macro but tell it to
ignore the Return-Path line in the header?
There's probably some way within procmail without the extra fork of
formail, but this is easy to think of and easy to write:
:0h
HEAD_WITHOUT_FROM_=| formail -IReturn-Path: -I'From '
:0
* HEAD_WITHOUT_FROM_ ?? ^FROM_MAILER
action
If you want to consider only the From: header, try this:
:0
* ^\/From:.*
* MATCH ?? ^FROM_MAILER
action
21.0 Technical matters
21.1 List of exit codes
The right place to look is /usr/include/sysexits.h, but the codes
should be pretty much standard. These ones are from HP-UX 10 and
the code that you will be using mostly is EX_NOUSER or EX_NOPERM.
It tells to the sender of UBE to "piss off and delete me from your
list; I'm not here"
EX_OK 0 successful termination
EX__BASE 64 base value for error messages
EX_USAGE 64 command line usage error
EX_DATAERR 65 data format error
EX_NOINPUT 66 cannot open input
EX_NOUSER 67 addressee unknown
EX_NOHOST 68 host name unknown
EX_UNAVAILABLE 69 service unavailable
EX_SOFTWARE 70 internal software error
EX_OSERR 71 system error (e.g., can't fork)
EX_OSFILE 72 critical OS file missing
EX_CANTCREAT 73 can't create (user) output file
EX_IOERR 74 input/output error
EX_TEMPFAIL 75 temp failure; user is invited to retry
EX_PROTOCOL 76 remote error in protocol
EX_NOPERM 77 permission denied
I thought that by using the EXITCODE, I would be assured that the
email would be *rejected* but in fact Sendmail 8.8.7 attempts to
deliver the "user unknown" to netcom.com, which is obviously
wrong?
[sean] Sendmail accepts the message, then passes it on to
Procmail, either as the local delivery agent, or via a .forward
file (depending on your system's configuration). Procmail says "gee,
gotta lie about not being here" and rejects the message, when is
sent back into the spool, and delivered according to who it
appeared to come from.
Had SENDMAIL determined the user didn't exist (password file /
aliases / virtusertable.txt), then it would have rejected the
message right when the remote was doing SMTP RCPT. But the user WAS
valid, and so it accepted it.
Another scenario is when you have a mail secondary, and your
primary (where the user account and procmail are) is down. Some
system goes to deliver mail to you, and resolves to your secondary
-- which simply holds mail for your primary -- it hasn't a clue
which user is valid and which isn't. Well, the (E)HELO (the system
sending your primary the message) takes place during the SMTP
session, the message is coming from your secondary - not from the
original sender. At THAT point, if the user didn't exist, I believe
sendmail would be issuing an unknown user error to the secondary,
which in turn should mail that message back to who it thinks is the
sender (I can't check my Bat book from where I'm at - any sendmail
pros are welcome to elaborate).
is there any way at all to get around this (force the rejection
at delivery time)? Better yet, is there some sort of check to
make sure that the Received domain reasonably matches the From:
domain?
You'd need to have a ruleset in your SMTP Daemon (generally
Sendmail) to check domains (which WILL fail on many valid messages,
BTW) and reject it WHILE the SMTP delivery session (actually, the
negotiation) is in progress. By the time Procmail has the message,
you've completely accepted the message, and any rejection you might
hope to do is bouncing the mail - to the apparent sender.
Such is the problem with forged mail.
I wouldn't suggest this tactic for fighting spam anyway - so much
of it is forged, and any bounce you send out simply uses up system
resources on your machine and those on the system that was spoofed.
Spammers don't REMOVE addresses from their lists (they want the
lists to look as big as possible when they go to sell it to someone
else) -- some have even taken to GENERATING addresses at domains
and sending messages to them with the assumption that somebody will
probably have an account by that name ("bill@ joe@ dave@ ...").
Use procmail to trashbin (or otherwise file) all the junk and then
manually take action on those which get through.
21.2 List of precedence codes
The priorities most sendmails recognize are following. The lower
the priority, the later the message gets dealt with. A smart
vacation program will ignore anything with a list, bulk, or junk
priority. --Adam Shostack
0 first-class
30 list
60 bulk
100 junk
100 special-delivery
[dan] You should use `bulk' when you distribute files via File
Server. The value in the Precedence: header says absolutely NOTHING
about the contents of the message itself, it merely suggests a
priority level to the mail system. From pp. 668 of the O'Reilly's
*sendmail* book, bulk typically has a value of -200 while `junk'
-100; thus a message with `junk' will get *higher* priority than
that of `bulk' (although this can be changed in the `sendmail.cf'
file).
Other than on heavily loaded machines, this value won't matter
anyway, since all mail will be quickly processed.
[Stephen] ...Mail sent by a person is usually considered to be more
important than autoreplies generated by some daemon. One way to
express the lower priority of autoreplies is by adding a
"Precedence: junk" field. This allows mail transport agents to
make educated decisions about which mail to forward first (in case
the mailqueue gets clogged).
Another point is: other autoreply services, like `vacation'. They
try to make an effort not to accidentally reply to a message
generated by another daemon (e.g. yours). One way they detect this
is by looking at the Precedence field. If it contains `junk', they
know, this is not something we should respond to.
21.3 Sendmail and -t
sendmail -t tag reads To, Cc, Bcc, etc, for the recipient of
the auto response?
:0h
* condition
* !^X-Loop: foo@site\.com
| ($FORMAIL -rA "X-Loop: foo@example.com" ) | sendmail -oi -t
[david] That's not a problem, because formail -r will not generate
any Cc: or Bcc: headers unless you tell formail to add them. The
only line where sendmail -t will look for recipients will be the
To: line.
21.4 RFC822 Reply-To and formail problem with multiple recipients
[david] formail -r extracts only one return address, even when the
Resent-Reply-To: or Reply-To: header contains more than one (and
Stephen has told me he plans to leave it that way).
o Looking for the best address to reply to is a completely different
algorithm than looking for the best group of addresses to reply
to. Finding a group of addresses involves actually determining
that you even are searching for a group and not only for one
address. Then finding out the best address for each. It's already
a tricky business doing this just for one address.
o It makes thousands of autoreply recipes vulnerable to mail-storm
attacks. Formail tries its best to control the damage even if
operated by someone who doesn't know what he is doing. If it were
to reply to multiple addresses at times, this damage control is
severely undermined.
[dan]I understand these concerns; however RFC822 specifically
allows for multiple recipients in a Reply-To: header. Given that, it
seems that there should be a straight-forward way to deal with this in
formail; even worse is that "formail" silently ignores multiple
Reply-To: addresses.
For (a), wouldn't the Reply-To: (or Resent-Reply-To:) header supersede
all other addresses and thus greatly simplify the searching? For (b),
how about only using multiple (Resent-)Reply-To: addresses if
formail's "-t" option is also specified? Or if you are really worried
about mail-storms and existing recipes, a new formail option.
21.5 Procmail and IMAP server
[ed] See also ftp://ftp.cac.washington.edu/mail/imap.vs.pop ...This
paper is an elaboration on a short note entitled "Comparing Two
Approaches to Remote Mailbox Access: IMAP vs. POP", which was written
in 1993 and recently updated. The purpose of this paper is to provide
more extensive background on message access paradigms and protocols,
and then to specifically compare the Internet's Post Office Protocol
(POP) and the Internet Message Access Protocol (IMAP) in the context
of "online" operation.
...I log in to a set of NFS-ed servers (or more precisely AFS-ed),
and my mail comes into another server (not a part of this set)
which is running IMAP. So sendmail never delivers mail into
/var/mail/$LOGNAME on my login machines, and instead delivers to
the IMAP server. Since sendmail never reads my .forward file in
the home directory, I figure procmail never gets invoked.
You need a program which will fetch your e-mail from the IMAP
server and then feed it to procmail. One such program that can do
this is fetchmail. Check out http://locke.ccil.org/~esr/fetchmail/.
The bad news is that once you do this, you probably won't be able
to use an IMAP client to read your e-mail anymore. But that might
be good news if you prefer an MUA that reads mbox files but doesn't
grok IMAP.
21.6 Machine which processes mail
...The just-installed procmail does not work and I am assuming
that sendmail is trying to run procmail on another machine. Is
there anyway I could find out the appropriate ARCHITECTURE for
that machine
[era] The following should tell you the name of the machine which
processes mail for the machine you're asking about. You can then
try to log in to that machine if you have shell access there, which
is something you need to have in order to compile Procmail on it.
nslookup -q=mx machine # alternatively use host(1) command
If you don't have nslookup (doh) or don't understand what it says,
try adding this to your .forward
"|uname -a >/full/path/to/home/.uname.out"
i.e. this should be there in +addition+ to what else you do.
Otherwise this will lose your mail thoroughly, since it reads the
mail but doesn't save it anywhere. You might want to save a copy of
all incoming mail to a safety mailbox, too, just in case. Like so:
/full/path/to/home/safetymailbox
|"uname -a >/full/path/to/home/.uname.out"
|"IFS=' '&& exec /usr/local/bin/procmail -Yf- || exit 75"
If you try this, it is very important that the file safetymailbox
exists and is writable. (`man' `5' `forward' if you have that -- I
don't seem to have this manual page on systems with newish versions
of sendmail, is that correct?)
Try the `uname' command (and/or read the manual) to see what you
should expect to find in the file .uname.out
21.7 Compiling procmail and MAILSPOOLHOME
...I am compiling 3.11pre7 on a new system and have a couple of
questions. I edited the makefile to be the home directory
"/home/a/abc" for example. I defined MAILSPOOLHOME as "/mail".
The incoming mail is actually stored in "/usr/mail/abc". When I
pipe test messages through procmail (using
"procmail] ...The trouble with rapid
delivery MTA's and SmartList(is not!) is multigram and the bounced
email processing feature and large lists. If you run small lists
it's not so bad. But with 30k+ subscriber monthly announcement
lists, I have to redirect bouncing email someplace else. The faster
the mail is delivered the faster the bounces come in. The larger
the list, the more multigram bogs down and the more procmail
processes accumulate and then you get file table overflows and all
that stuff from the load being sky high and hundreds of processes
hanging around. Also because alot of mail servers don't behave the
way we would like them to and return to us proprietary bounced
email messages that SmartList can't understand, the bounce feature
is only able to successfully remove a portion of the offensive
email addresses, requiring the listowner or some one to manually go
through it all anyway.
SmartList is not covered by the GNU GPL -- the copyright notice in
the docs do say that changes/modifications can be made if they are
'marked'.
Personally, I think the bounced email removal system needs to be
entirely redone if SmartList(is not!) is to be able to look forward
to the future enough to merit further development.
"Other MLM software"
o majordomo uses Perl
o Mailman uses Python http://www.list.org/
o SmartList uses scripts/procmail
o Listar Mailing List Package (free): http://www.nausicaa.net/~listar/
o L-Soft international, Inc. (non-free): http://www.lsoft.com/
o The Petidomo Mailing List Processor and Manager (non-free):
http://www.petidomo.com/
o Mailagent (free): http://www.foretune.co.jp/people/shigeya/mailagent/
o BeroList (free): http://www.in-trier.de/~bero/BeroList/
22.3 SmartList code (mailing list implementation with procmail)
"Smartlist 'faq'"
http://www.mindwell.com/smartlist/
"Mark's Smartlist add-ons"
Mark David mcCreary
ftp://ftp.mail-list.com/
...front-end for Smartlist mailing lists, and allows people to
mail to list-on@domain.com and list-off@domain.com, which then
creates and sends a properly formatted subscribe/unsubscribe
message to the list-request address.
It also handles change of address, switches to/from digest lists,
moderated subscriptions, and a few other things.
My experience is that if you are planning on running lots of
lists, then eliminating questions/problems from subscribers is of
paramount importance, and those procmail recipes may be worth the
time to learn/tweak. --Mark
"Michelle's (SmartList add-ons) Confirmation cookie"
ftp://ftp.fatfree.com/ confirm-1.1.tar.gz
ftp://ftp.rahul.net/pub2/artemis/ confirm-1.1.tar.gz
To add subscription confirmation to smartlist
"The mail-list.com front-end for Smartlist Mailing Lists"
ftp://ftp.mail-list.com mark david mcCreary to
start the subscription process.
"Auto respond to 'help: is there faq?' "
http://www2.inow.com/~conover/ rel.tar.zip
"Moderated lists -- Perl script"
http://www.mjolner.com/~lbr/moderate/
22.4 Installation trouble: getparams
Does anyone out there know what the error means when it occurs when
installing Smartlist? Procmail is already installed on the system
(by the sysops)
make: *** No rule to make target `getparams'
[Hal Wine] Yes, it means that you haven't built procmail yet. Build
procmail first, then execute Smartlist's install.sh script. You
need to get and untar the procmail sources in your own directory,
then get and untar the corresponding Smartlist sources in the same
directory tree.
Then build (but don't install) procmail, then install Smartlist
using the install.sh script. Smartlist uses and builds files in
the Procmail source tree, so that has to be done first
[sysops] don't have the time to mess with getting Smartlist
running. Obviously,when I attempt to install Smartlist, it's not
finding Procmail. What do I have to do to get the install
program to find Procmail?
If the sysops aren't going to install Smartlist, read all the
sections in Manual about non-root use of Smartlist (it works fine).
You should make sure that smartlist, when invoked, uses the
matching version of procmail. This means either use the version of
Smartlist that matches the sysop installed version of procmail, or
set up your PATH such that you use the version you built. If you
use your own version, make sure it uses the same locking strategies
as the "official" version.
22.5 Accepting mail only from users in whitelist(s)
1998-10-08 PM-L Dave Robbins.
ML = /usr/local/lib/aliases
ACCEPTLIST = "$ML/mylist.accept $ML/everyone $ML/others"
FROM = `$FORMAIL -rtzxTo:`
:0
* ? echo "$FROM" | $EGREP -i -f $ACCEPTLIST
* ? test -r $ACCEPTLIST -a -s $ACCEPTLIST
{
:0 HB
! `cat $ML/mylist`
}
:0
* ! ^FROM_DAEMON
* ! ^FROM_MAILER
*$ ! $MY_XLOOP_LIST
| ($FORMAIL -rtk \
-A "$MY_XLOOP_LIST" \
-A "Precedence: junk"; \
echo "Your post to mylist@magic.geol.ucsb.edu was not successful\n" \
"because the mailing list is restricted to submissions\n" \
"from only certain individuals and groups. Sorry.\n" \
) | $SENDMAIL -oi -t
23.0 Additional procmail or MUA software
23.1 Comstat to handle multiple mailboxes
ftp://ftp.belwue.de/pub/unix/xcomsat.tar.gz
23.2 Elm and pgp support (Mutt is the successor to elm.)
Mutt's primary site is
ftp://ftp.guug.de/pub/mutt/
with various mirrors outside the US to avoid the crypto distribution
problem.
If you want elm,
"Michael Elkins' ftp directory"
ftp://ftp.cs.hmc.edu/pub/me/
http://www.cs.hmc.edu/~me/mutt/
http://www.cs.hmc.edu/~me/elm/me.html
[Liviu Daia mentions that] ...Provided that
you configure it correctly, it will use lynx to convert HTML
attachments to plain text automatically, and display them in its
pager. You can reply in plain text to those attachments, and you
can also do the same thing with any kind of attachment for which
you give it a way to convert to plain text. It's definitely not
aimed at the beginner level like Pine, but it's far more powerful
too. Also GPL-ed.
23.3 MH sites
"New MH"
ftp://ftp.math.gatech.edu/pub/nmh/nmh.tar.gz
http://www.math.gatech.edu/nmh/
24.0 Additional procmail software for Emacs
24.1 What is Emacs
...first thing I learned on a Unix machine was that `vi' is a text
editor and `Emacs' is a way of life.
--David W. Tamkin
_Emacs_ refers to a programming platform (it's not only a text
editor, or a programming editor, but it does almost everything you
tell it to do except make your coffee) which can be found almost
in any Unix platform. Nowadays Emacs is also available for the PC
platform too. There are two flavours to choose from: Emacs,
maintained by the FSF (Free Software Foundation), and XEmacs,
sometimes called "Emacs the next generation", because it has a
better graphical user interface (gui) and internally advanced OO
design (it can highlight on tty, whereas Emacs can't). XEmacs is
being maintained by group of programming wizards.
See #URL-BASE/elisp.html
Emacs add-in packages are lisp and the lisp file extension is
*.el*. Inside each package one finds instructions how to use and
how to install the package into Emacs.
24.2 Emacs and procmail mode and Lint
Procmail mode for Emacs (which can also lint
procmail recipes) is available. People familiar with C-coding know lint,
which is a rigorous code syntax checker. You can read about this
Emacs mode from
http://poboxes.com/jari.aalto/tiny-tools.tar.gz
24.3 Emacs and lining up backslashes
Some time ago I wrote makefile to my Emacs tgz kit and as a side
effect I got frustrated with the use of backslashes within the make
rules. This backslash problem is universal in almost every
programming language, (eg. C/C++ macros) including procmail, where
you sometimes use `echo' a lot,
:0 h
* condition
| ( cat -; \
echo "And the body text\n" \
"follows here with\n" \
"these echoes"; \
) | $SENDMAIL
Ouch. That looks bad. Any line up tool anywhere? Yes, get my Emacs
tiny-tools.tar.gz and look at the file `tinymy.el' which defines
function `timy-backslash-fix-paragraph'. Here is piece of lisp code
that you stick to your .emacs to make the key `Control-\' to run the
backslash fix
(global-set-key "\C-\\" 'my-backslash-default-column)
(defun my-backslash-default-column (&optional arg)
"Col 76."
(interactive "*P")
(autoload 'timy-backslash-fix-paragraph "tinymy" t t)
(timy-backslash-fix-paragraph (or arg 76) 'verb)
)
After that, you just put your cursor inside paragraph and hit
`Control-\' to get the following line up effect. The column position
is best to set near right margin, but not further than a regular
page's maximum column 80.
:0 h
* condition
| ( cat -; \
echo "And the body text\n"; \
"follows here with\n"; \
"these echoes"; \
) | $SENDMAIL
Guys, Emacs is available for every platform, even for Windows95 and
WindowsNT. So, go ahead and install one if you haven't already.
Setting up your personalised Emacs may require steep learning curve,
but it's well worth the effort :-)
24.4 Emacs and browsing mailbox files
If you use Gnus as your MUA, then you already can browse mailboxes.
If you just want to read some arbitrary mailbox without firing up
Gnus, then you can use package `tinymbx.el' It defines a special
mailbox reading minor mode that is activated when you visit mailbox
file. You can copy, file, delete messages or mail the author of the
current message. There is no separate summary buffer as in RMAIL, but
you move from message to another with PgUp and PgDown keys.
#URL-BASE/tiny-tools.tar.gz
24.5 Emacs and live-mode.el
http://www.zanshin.com/~bobg/
from Bob Glickstein 1997
...`live-mode' is a minor mode that works like the "tail -f" Unix
command. If the file grows (or changes in any other way) on the
disk, then the buffer copy is periodically updated to show the new
file contents. This makes `live-mode' ideal for viewing such things
as log files. --Bob
You definitely want this if you browse procmail log files. This
package updates the logfile buffers whenever they change on disk.
You can think it like *biff* if you record incoming file to short
`$BIFF' log.
24.6 Emacs and font-lock.el
`Font-lock' comes standard in Emacs releases. You can colorize your
.procmailrc if you use `font-lock'. Here is some lisp code; put it
in your .emacs and reload it with `M-x' `load-file'. When you load
file that matches `procmailrc' or `procmail.log' the font-lock
attributes for the file get set. Change the regexp if your procmail
filenames are different.
(add-hook 'find-file-hooks 'my-find-file-hooks)
(defun 'my-find-file-hooks ()
(require 'cl)
;; colors are available to Emacs only under X window
(when (and window-system
(fboundp 'font-lock-mode) ;; make sure this is present
)
(cond
((string-match "procmailrc" buffer-file-name)
(setq font-lock-keywords
(list
'("#.*" . font-lock-comment-face)
'("^[\t ]*:.*" . font-lock-type-face)
'("[A-Za-z_]+=.*" . font-lock-keyword-face)
'("^\\*.*" . font-lock-doc-string-face)
))
;; Turn the fontifying mode on if it's not on already
(unless font-lock-mode (font-lock-mode 1))
)
((string-match "procmail.log" buffer-file-name)
;; The strings "" in the procmail log makes font-lock crazy,
;; We kill the String class from the buffer with
;; these statements.
;;
(let ((table (make-syntax-table)))
(modify-syntax-entry ?\" "_" table) ;; Change "
(set-syntax-table table))
(setq font-lock-keywords
(list
(cons "Opening " 'font-lock-type-face)
(cons ".* error .*" 'font-lock-keyword-face)
(cons "Folder:" 'font-lock-type-face)
))
(unless font-lock-mode (font-lock-mode 1))
))
))
;; End code
25.0 Procmail, Emacs and Gnus
25.1 Gnus pointers
"Gnus"
http://www.ifi.uio.no/~larsi
"Gnus manual: procmail"
http://www.ifi.uio.no/~larsi/www.gnus.org/manual/gnus_6.html#IDX1501
"Gnus Hypertext search archive"
http://www.miranova.com/gnus-list/
25.2 Why use procmail with Gnus
Gnus has very powerful mail split methods and one normal reaction
against the need of procmail is: "Hey, Gnus does my mail splitting,
I don't need procmail". The difference between Gnus and procmail
splitting is quite easily explained: you want procmail to
preprocess the mail before gnus ever sees it and then postprocess
the mail with Gnus (read, move mail from the inbox to another)
_Case1_: Gnus and regular mailbox, no procmail. Gnus reads directly
one huge mailbox where all incoming messages are. When the user
starts Gnus, it slurps in the whole mailbox and starts splitting the
mail according to the its split rules.
mail -> $MAIL --> fire up Gnus --> split1.mbx split2.mbx ....
_Case2_: procmail and Gnus. The email is always delivered to
procmail first. Procmail is free to put the mail anywhere or just
let it drop to the user's default inbox, usually pointed by
environment variable $MAIL.
mail -> procmail --> Post processing with Gnus
[the ~/Mail/spool]
--> split1.mbx
--> split2.mbx
[The default procmail rule drops to inbox]
--> $MAIL
You can let gnus to process the messages further: like moving
messages from one inbox to another.
Summary
o If you use procmail, the incoming messages are immediately
categorized. The incoming email is put in the folder of your
choice. The mailboxes are there waiting for you all the time. You
can use `less' or `more' to view them in a hurry.
o If you don't use procmail and let Gnus to do all the splitting,
you always see one huge inbox, $MAIL. It will not be split
until you fire up Emacs and Gnus. If you're in a hurry, you
may not have time to start Emacs & Gnus, before reading the
important messages. Your only option is to read all messages
in $MAIL and try to find the ones that consider eg. you work.
So, let procmail drop messages to their inboxes and Gnus to
possibly "fine process" these inboxes.
25.3 Setting up gnus for procmail - Basics
Procmail and Gnus communicate with each other very nicely when you
use the mail backends like: `nnml', `nnmh' and `nnfolder'. See
Emacs info Gnus::Node: `Select' `Methods' for more.
Here are step by step instructions for reading the mail with `nnml'
mail backend. We suppose that you have the following definition in your
.procmailrc so that the incoming mail is delivered to the right
directory.
The important point here is that the name of the gnus `nnml' group
is identical; except the `.spool' suffix, to the spool file where
procmail writes. So if you write to `list.procmail.spool', the
group name in gnus is named `nnml:list.procmail'
# .procmailrc excerpt
PMSRC = $HOME/pm
MAILDIR = $HOME/Mail
SPOOL = $MAILDIR/spool
RC_LIST = $PMSRC/pm-jalist.rc
# The file name must be list.xxxxx.spool in order to
# `nnml' to work in Gnus.Define procmail mailing list
PROCMAIL_SPOOL = $SPOOL/list.procmail.spool
# GNUS must have unique message headers, generate one
# if it isn't there. By Joe Hildebrand
:0 fhw
| $FORMAIL -a Message-Id: -a "Subject: (None)"
# detect mailing lists and store messages to spool directory
INCLUDERC = $RC_LIST
:0 :
* ! LIST ?? ^^^^
$SPOOL/list.$LIST.spool
. Copy the Lisp code below to your ~/.gnus
. Start Gnus with `M-x' `gnus-no-server' (M-x means ESC
followed by x). You will see *Group* buffer to appear.
. Make the new group with `G' `m' `list.procmail' RET `nnml' RET.
You can read the group as usual and query new mail with `g'
command.
(setq
gnus-secondary-select-methods '((nnml ""))
;; See also nnmail-procmail-suffix which is .spool by
;; default
;;
nnmail-use-procmail t
nnmail-spool-file 'procmail
nnmail-procmail-directory "~/Mail/spool/"
nnmail-delete-incoming t
)
And then I have procmail always deliver to ~/Mail/spool/. If you
add more inboxes, create them inside gnus *Group* buffer with
`G' `m'.
25.4 Gnus for procmail - More gnus
Okay, let's continue our journey in Emacs. What you read previously
was the minimum you needed to get your Gnus to read procmail
delivered files. However, if you're new to Gnus, here are some more
tips and basic instructions. The best advice I can give is that you
go to each buffer: In group, you press `G' `C-h' and in Summary
`C-h' `m' and print the commands to printer that you see listed.
In Group buffer
o When you press `g' to get new mail to these groups, the
group _disappears_ if there is no mail. If you want the
group to be permanently visible, then set
(setq gnus-permanently-visible-groups "^nnml\\|^nnfolder")
In emergency, press `L' to list all groups.
o If you made a mistake and wrote `list.procmaill' with an
extra `l' accidentally in the group name, use `G' `r' to
rename group.
o Raise or lower the priority of your procmail mail groups
with `S' `l'. Values 1 or 2 or 3 are good. Consider reserving
1 for your primary mail and 2 and 3 for mailing lists.
o When you exit a group and have read some articles, they won't show
up next time you go there. But by giving prefix argument before
entering the group with `SPC', Gnus will list all read articles.
You give the command like `C-u' `SPC', where `C-u' is the
prefix argument.
Settings
o You want gnus to tell you everything it does
(setq gnus-verbose 10) ;; 0..10
o You expire articles (get permanently rid of them) with the 'E'
command in the *Summary* buffer. The default expiry time is 7
days. You can define the expiry time in days with
(setq nnmail-expiry-wait 7)
o If you read mailing lists, you want automatic expiry when you
have read the article. Use the following to set up groups that use
this automatic expiration.
(setq gnus-auto-expirable-newsgroups
(concat
"procmail"
"\\|other-list"
"\\|and-some-other-list"
))
o `B' `e' in the *Summary* buffer expires current expirable articles.
o If you want to kill an article; permanently remove it from disk,
use `B' `delete'.
o If you want to mark an article as *persistent* (never expires),
use `*'
o You don't want these mail groups cached because mail is
already in "cache" format. The cache is needed only when you
read newsgroups and want to store messages locally.
(setq gnus-uncacheable-groups "^nn\\(virtual\\|m[hlk]\\|db\\)")
25.5 Emacs and Gnus -- Fiddling with spool files
Well, to tell you the truth, managing Gnus is scary at first: You
can make a lot of mistakes along the way or otherwise change your mind
about group names and so on. It's a tricky task to move mail from one
directory to another if you decide to rename the spool file name
where procmail is putting the filtered mail.
Let's take an example: Say you decide to change the spool file name
list.procmail.spool to mail.procmail.spool, because you come to
think that all your mail groups should have the same prefix "mail."
in your Gnus group buffer. You already changed procmail to
output to that file, so now you have two files sitting in your
spool directory.
~/Mail/spool/list.procmail.spool
~/Mail/spool/mail.procmail.spool # make sure this exists
o Let Gnus read the old file as usual. Press `g' read new mail to
`list.procmail'. list.procmail.spool will now be empty and
merged to `nnml' backend file nnml:list.procmail.
o Make a new group with `G' `m' nnmail `mail.procmail' in *Group*
buffer.
o Go to the old `list.procmail' group and select all articles with `M'
`P' `a'. Move the messages with `B' `m' to `mail.procmail'.
You will see `G' marks appear to the beginning of moved articles.
o Exit the *Summary* buffer and hit `g' to see that the
messages hat were transferred to your new `mail.procmail'
o Kill the old group |
