
getmail documentation

   This is the documentation for getmail version 4. Version 4 includes
   numerous changes from version 3.x; if you are using getmail version 3,
   please refer to the documentation included with that version of the
   software.
   
   getmail is Copyright © 1998-2005 Charles Cazabon.
   
   getmail is licensed under the GNU General Public License version 2
   (only). If you wish to obtain a license to distribute getmail under
   other terms, please contact me directly.
   
Frequently-Asked Questions (FAQs)

   The following questions about getmail are answered more-or-less
   frequently. Please also read the unexpected behaviour section of the
   troubleshooting document.
   
About getmail

What is getmail?

   getmail is a mail retriever with support for POP3, POP3-over-SSL,
   IMAP4, IMAP4-over-SSL, and SDPS mail accounts. It supports normal
   single-user mail accounts and multidrop (domain) mailboxes. getmail is
   written in Python, and licensed under the GNU General Public License
   version 2.
   
What platforms/machines does getmail run on?

   getmail runs on basically any platform. It's designed to, and written
   in a language that helps to maintain cross-platform compatibility.
   getmail is known to run on the following platforms:
     * Linux-based GNU systems (all distributions)
     * HURD-based GNU systems
     * FreeBSD
     * OpenBSD
     * NetBSD
     * HP/UX
     * Sun Solaris
     * IBM AIX
     * Digital/Compaq Tru64 (a.k.a OSF/1) UNIX
     * SGI Irix
     * other commercial Unices
     * Digital VMS / OpenVMS
     * BeOS
     * Amiga OS
     * OS/2
     * Cygwin on Windows
     * Macintosh OS X
     * Macintosh OS 9
       
   But getmail will also run on other, less common platforms. The only
   real requirement is that Python run on that platform, and porting
   Python is generally very easy.
   
Does getmail run on MS Windows?

   Yes, under the free Cygwin package. Running recent versions of Python
   under Cygwin requires a process known as "rebasing" your Cygwin
   installation; you can find details in this Python developers' mailing
   list message.
   
Does getmail run on Macintosh systems?

   Yes.
   
Does getmail require Unix/Linux?

   No.
   
How can I get support for getmail?

   getmail is Free Software. As such, it comes with no warranty. However,
   I will do my best to support getmail on a voluntary basis through the
   getmail mailing list.
   
   If you are using getmail in a commercial or other environment where
   problems cost money, consider contacting me privately for commercial
   support, by emailing <getmail-support @ discworld.dyndns.org>
   
   If you have questions about getmail, the first step is to read the
   documentation, and the remainder of the Frequently Asked Questions. If
   your question isn't answered there, search the getmail mailing list
   archives.
   
   If you still haven't found an answer to your question, please
   subscribe to the getmail users' mailing list by sending a blank email
   to <getmail-subscribe @ discworld.dnsalias.org>. If you post your
   question there, I will see it. As an additional bonus, your question
   may be answered by another member of the list.
   
I think I found a bug! How do I report it?

   First, make sure that you are running the latest version. You can
   always find what is the latest version by checking this page at the
   original web site:
   http://pyropus.ca/software/getmail/.
   If you running an older version of the software, chances are whatever
   bug you may have found has already been fixed.
   
   Ideally, you should join the mailing list and send your bug report
   there. You should include the following information:
     * getmail version
     * Python version
     * any error message which getmail displayed
     * the output from running getmail with your normal options plus
       --dump
     * if your problem is getmail not determining the proper local
       recipient, please include the output of running getmail with your
       normal options plus --trace, showing the retrieval of one
       problematic message.
       
   If you absolutely cannot sign up for the mailing list, send the report
   to me directly at <getmail-bugs @ discworld.dyndns.org>. I may not be
   able to respond to all reports privately, but I will try to address
   any bugs I find out about this way.
   
I have a neat idea for random feature "foo" ... how do I get you to
implement it?

   Follow the same instructions as for reporting bugs above -- yes, that
   means I would prefer you submit your idea to the getmail users'
   mailing list. That will lead to a useful discussion if your feature
   has not been proposed before.
   
Why won't you implement random feature "foo"?

   Every line of code added to getmail has a certain cost. Every feature
   added requires code, documentation, and support. Adding features
   increases the complexity of the software, confuses users, and leads to
   higher support costs. I therefore weigh features very carefully as a
   cost-versus-benefit tradeoff before deciding whether to add them.
   
   Some users are confused by this. They think that a feature you don't
   use has no cost, and therefore if it has any value to anyone, it
   should be added. That simply isn't the case; the costs of an unused
   feature are simply borne by others, including me.
   
   If you have asked me to add some feature, and I've said no, this may
   be the reason. Other possibilities include me simply not having had
   sufficient time to implement it yet.
   
Does getmail support virus scanning of retrieved messages?

   Yes. You can use getmail message filtering options to do this with an
   external virus scanning program, or invoke your virus scanning program
   during delivery with getmail's support for external MDAs.
   
   Also see the FAQ about using getmail with the ClamAV program.
   
Does getmail support spam filtering of retrieved messages?

   Yes. You can use getmail message filtering options to do this with an
   external spam filtering program, or invoke your spam filtering program
   during delivery with getmail's support for external MDAs.
   
   Also see the FAQ about using getmail with the SpamAssassin program.
   
Does getmail support SSL?

   Yes. getmail has built in support for POP3-over-SSL and
   IMAP4-over-SSL.
   
Does getmail rewrite mail headers when it retrieves mail?

   No. Rewriting message header fields is bad for many reasons; the
   biggest problem is that it causes a loss of critical technical
   information necessary to track down many mail problems. getmail will
   add a new Received: header field and a new Delivered-To: header field,
   but does not rewrite existing headers. You can disable the creation of
   these header fields.
   
Can I upgrade from getmail 3 to getmail 4? What about my "oldmail" files?

   Yes. getmail version 4 uses exactly the same
   oldmail-server-port-username naming convention for its oldmail files.
   The only difference is that version 4 escapes a couple of additional
   characters in this string so that it is truly cross-platform
   compatible. If you upgrade from version 3 to version 4, getmail will
   still remember which messages you've already retrieved.
   
   To upgrade, do the following:
    1. Rename your old getmail rc file, creating a new file in
       ~/.getmail/getmailrc.
    2. Create a new [options] section, containing the appropriate values
       from your version 3 rc file [defaults] section.
    3. Create a new [retriever] section, using your previous server
       configuration values in a new type = SimplePOP3Retriever or type =
       MultidropPOP3Retriever as appropriate.
    4. Create a new [destination] section, using your previous
       destination path values in a new type = Maildir, type = Mboxrd,
       type = MDA_external, or type = MultiSorter destination as
       appropriate.
    5. If you were retrieving messages from multiple mail accounts in a
       single version 3 getmail rc file, split them up into one account
       per version 4 rc file.
       
   That's it.
   
Why did you write getmail? Why not just use fetchmail?

   Short answer: ... well, the short answer is mostly unprintable. The
   long answer is ... well, long:
   
   I do not like some of the design choices which were made with
   fetchmail. getmail does things a little differently, and for my
   purposes, better. In addition, most people find getmail easier to
   configure and use than fetchmail. Perhaps most importantly, getmail
   goes to great lengths to ensure that mail is never lost, while
   fetchmail (in its default configuration) frequently loses mail, causes
   mail loops, bounces legitimate messages, and causes many other
   problems.
   
   When people have pointed out problems in fetchmail's design and
   implementation, it's maintainer has frequently ignored them, or (worse
   yet) gone in the completely wrong direction in the name of "fixing"
   the problems. For instance, fetchmail's configuration file syntax has
   been criticized as being needlessly difficult to write; instead of
   cleaning up the syntax, the maintainer instead included a GUI
   configuration-file-writing program, leading to comments like:
   
     The punchline is that fetchmail sucks, even if it does have
     giddily-engineered whizbang configurator apps.
     
   As an example, Dan Bernstein, author of qmail and other software
   packages, once noted to the qmail list:
   
     Last night, root@xxxxxxxxxxxxxxxxx reinjected thirty old messages
     from various authors to qmail@xxxxxxxxxxxxxx
     
     This sort of idiocy happens much more often than most subscribers
     know, thanks to a broken piece of software by Eric Raymond called
     fetchmail. Fortunately, qmail and ezmlm have loop-prevention
     mechanisms that stop these messages before they are distributed to
     subscribers. The messages end up bouncing to the wrong place,
     thanks to another fetchmail bug, but at least the mailing list is
     protected.
     
     --D. J. Bernstein
     
   The maintainer also ignored dozens of complaints about fetchmail's
   behaviour, stating (by fiat) that fetchmail was bug-free and had
   entered "maintenance mode", allowing him to ignore further bug
   reports.
   
   fetchmail's default configuration values frequently cause lost or
   misdirected mail, and seem to be chosen to cause maximum pain and
   inconvenience. From fetchmail's to-do file (emphasis mine):
   
     Maybe refuse multidrop configuration unless "envelope" is
     _explicitly_ configured ... This would prevent a significant class
     of shoot-self-in-foot problems.
     
     perhaps treat a delivery as "temporarily failed" ... This is so you
     don't lose mail if you configure the wrong envelope header.
     
   fetchmail is famous for mangling messages it retrieves, rather than
   leaving them alone as a mail-handling program should. getmail will add
   trace information to messages (so you can see what happened, and
   when), but will otherwise leave message content alone.
   
   In addition, fetchmail has a long history of security problems:
     * versions released before 20 June 2001 contain a buffer overflow,
       which can be remotely exploited (see
       www.securityfocus.com/bid/2877 for details). getmail is not
       vulnerable to buffer overflows, because buffers in Python are
       dynamically sized.
     * Another remotely-exploitable security hole discovered in fetchmail
       in June 2002; versions prior to 5.9.10 (released in June 2002) are
       exploitable .
     * Reading fetchmail's UPDATES file, it appears that another security
       problem was fixed in 5.9.12, where a server could crash fetchmail
       on 64-bit platforms. Also worrying is a mention that it includes a
       fix for "password shrouding".
     * Another remotely-exploitable security hole in fetchmail discovered
       in September 2002; this hole lets an attacker run arbitrary code
       on the victim's computer.
     * Another remotely-exploitable security hole in fetchmail discovered
       in December 2002; once again, a remote attacker can run arbitrary
       code on the machine running fetchmail in its default
       configuration. See this advisory for details.
     * January 2003: More buffer overflows in fetchmail let attackers run
       arbitrary code .
     * October 2003: Anyone can cause fetchmail to crash by sending you a
       message . Other problems are here , and I might have missed some .
       
   As of July, 2004, there may be at least 2 unfixed denial-of-service
   attacks, 2 unfixed remote-code-execution, 2 unfixed
   remote-user-access, and 3 unfixed remote-shell attacks against
   fetchmail. See
   http://www.mail-archive.com/euglug@euglug.org/msg00971.html for
   details
   
   I've given up even trying to stay abreast of the various security
   holes in fetchmail.
   
   But don't just take my word for it; see
   http://docs.freebsd.org/cgi/mid.cgi?200102172349.QAA11724 and
   http://esr.1accesshost.com/.
   
   getmail users have not had to worry about any of these security holes
   or design and implementation errors.
   
Configuring getmail

What is a "domain mailbox"?

   A domain (or multidrop) mailbox is a POP3 mailbox which receives mail
   for all users in a given domain. Normal mailboxes contain mail for a
   single user (like jason@myisp.co.uk); some Internet Service Providers
   which provide webhosting or other services will provide a POP3 mailbox
   which receives mail for all addresses in a given domain (i.e. mail for
   service@smallcompany.net, sales@smallcompany.net, and indeed anything
   @smallcompany.net ends up in the same POP3 mailbox).
   
   getmail provides a method of retrieving mail from a domain mailbox and
   distributing it among the various users automatically. The retriever
   classes MultidropPOP3Retriever, MultidropPOP3SSLRetriever,
   MultidropSDPSRetriever, MultidropIMAPRetriever, and
   MultidropIMAPSSLRetriever provide this capability.
   
   See the documentation on the [retriever] section for details of what
   the requirements for a multidrop mailbox are. getmail user Matthias
   Andree also has a web page about multidrop mailboxes.
   
Do I have to run sendmail or another MTA to use getmail?

   No. getmail delivers directly to maildirs, mboxrd files, or via
   arbitrary MDAs, and never injects mail via SMTP, so no MTA is
   necessary.
   
Will getmail deliver mail as root?

   No. When run as the root user on a Unix-like system, getmail drops
   privileges (switches to an unprivileged group and user id) before
   delivering to maildirs or mboxrd files. You can specify the user
   explicitly, or let getmail use the owner of the maildir or mboxrd
   file.
   
   If getmail attempts to deliver mail and finds it has UID 0 or GID 0,
   it will refuse the delivery and print an error message.
   
What's a maildir?

   A maildir is a mail storage format invented by D. J. Bernstein (author
   of qmail) that requires no file locking to deliver to safely and
   reliably, even over NFS. getmail natively supports delivery to
   maildirs.
   
   See http://qmail.org/man/man5/maildir.html and
   http://cr.yp.to/proto/maildir.html for details.
   
What's "mboxrd" format?

   There are various sub-types of the mbox mail storage format. mboxrd is
   the most reliable of them, though (like all mbox types) it still
   relies on file locking and is therefore more easily corrupted than
   maildir format. In particular, using mbox files with multiple writers
   over NFS can be problematic.
   
   For details on the differences between the various mbox sub-types, see
   http://qmail.org/man/man5/mbox.html.
   
What's this "envelope sender" and "envelope recipient" stuff?

   The "envelope" of an email message is "message metadata"; that is, the
   message is information, and the envelope is information about the
   message (information about other information). Knowing this is
   critical to understanding what a domain or multidrop mailbox is, how
   it works, and what getmail can do for you.
   
   Others have tried to explain this with varying degrees of success.
   I'll use the standard analogy of normal postal (i.e. non-electronic)
   mail:
   
Message header vs. message envelope

   When you receive a letter (a reply from the customer-disservice
   department of your telephone company, say) it arrives in an envelope.
   You tear it open, remove the letter, and read it. At the top of the
   letter is the telephone company's return address, followed by the date
   the letter was written. Your name and mailing address follow that, and
   then the remainder of the letter.
   
   The important thing to keep in mind is that the contents of the letter
   (including the addresses just discussed) are never looked at by the
   post office. If they can't deliver the letter (your mailing address on
   the envelope got smudged in the rain), they'll return it to the
   address listed in the top-left corner of the envelope. They don't
   check to make sure that the address listed there is the same as the
   one listed at the top of the letter. Similarly, when they can
   successfully deliver it, they don't check to make sure that the
   recipient name and address on the envelope matches the one listed on
   the letter between the date and the salutation.
   
   The message header fields From: and Resent-from: are equivalent to the
   block of address information at the top of the letter; it usually
   contains the name and address of the sender of the message, but it is
   never actually used in the delivery of the message. Similarly, the
   To:, cc:, Resent-to:, and Resent-cc: header fields are the equivalent
   of the block of address information between the date and the
   salutation on the letter; they usually contain the names and addresses
   of the intended recipients of the message, but they too are not used
   in the delivery of the message.
   
Receiving messages without your address in the message header

   You might open an envelope addressed to you and find that the letter
   inside makes no mention of your name. Your name and address don't
   appear anywhere in the letter, but it was still successfully delivered
   to you based on the envelope information. There's nothing strange
   about this. If someone else opens your mail for you, discards the
   envelopes, and places the contents in your in-basket, you might wonder
   how some of it ended up there, because there's nothing to connect you
   with the message contents.
   
   Email is exactly like this. Each message has two parts, the message
   contents, and the message envelope. The message contents include the
   message header, and the message body. The message envelope is made up
   of exactly one envelope sender address (which can be empty) and one or
   more envelope recipient addresses. If the message cannot be delivered
   for any reason, and the envelope sender address is not empty, the
   message must be returned to the envelope sender address by the mail
   transfer agent (MTA) which last accepted responsibility for delivering
   the message. These notifications are known as "bounce messages" or
   sometimes as "non-delivery notifications". Bounce messages are sent
   using the empty envelope return path, to prevent mail loops from
   occurring when a bounce message itself cannot be delivered.
   
   Confusion often arises among novice users about the difference between
   the message header and the message envelope; they seem to believe that
   they are not independant. This appears to be an artifact of their use
   of simple-minded GUI mail user agents (MUAs) that do not allow them to
   set the envelopes of their messages explicitly, but instead simply use
   the contents of the From: header field as the envelope sender address,
   and any addresses found in To:, cc:, and bcc: header fields as the
   envelope recipient addresses. While these are sensible as default
   values, more powerful MUAs allow the user to override this choice.
   
Responsibility for recording the message envelope

   The last MTA to receive a message (usually the one running on the POP
   or IMAP server where you retrieve your mail from) essentially acts as
   your correspondence secretary, accepting your mail from the postman,
   opening it, and placing it into your in-basket. Note that this would
   normally destroy the important information contained in the message
   envelope. To prevent this loss of information, this MTA is supposed to
   copy the information from the envelope into new fields in the header
   of the message content, as if your secretrary copied the sender and
   recipient addresses onto the back of your letters in felt pen.
   Unfortunately, some MTAs do not always do this properly, and envelope
   information can then be lost. When this happens, it makes dealing with
   certain types of mail messages problematic:
     * bcc'd messages (bcc stands for blind carbon copy), where you are
       an envelope recipient, but your address does not appear in the
       message content (i.e., your address does not appear in a To:, cc:,
       or similar message header field). With bcc'd messages, the From:
       header field contains the name and address of the author of the
       message, and the To: and cc: header fields contain the names and
       addresses of the other, non-blind recipients of the message.
     * mailing list messages, where you are an envelope recipient, but
       your address does not appear in the message content (i.e., your
       address does not appear in a To:, cc:, or similar message header
       field). Mailing list messages have the envelope sender address set
       to the mailing list manager (so that it can monitor "bad" list
       addresses for bounces), while the From: header field contains the
       name and address of the author of the message. The envelope
       recipient addresses of mailing list messages are the addresses of
       the list subscribers, while the To: header field usually contains
       the address of the mailing list.
     * other, less common cases.
       
   MTAs are supposed to record the envelope sender address by placing it
   into a new Return-Path: header field at the top of the message. They
   should then record the envelope recipient address(es) in another new
   header field; sometimes this header field is named Delivered-To:, but
   it can also be Envelope-To: or one of a few other names.
   
How this relates to domain or multidrop mailboxes

   A domain or multidrop mailbox is one which receives mail for multiple
   email addresses (commonly all addresses in a given domain). If you do
   not want all of this mail to go to one person, you need to know who
   the messages were originally addressed to after retrieving them from
   the POP/IMAP multidrop mailbox. You cannot do this by looking at the
   To:, cc:, or other informational message header fields, because they
   do not actually reflect the message envelope at the time of delivery.
   Instead, you have to reconstruct the envelope information from the
   message header fields which the MTA on the server used to record it at
   the time of delivery.
   
   If the final MTA does not record the message envelope (the envelope
   sender, and all envelope recipient addresses in the domain mailbox the
   message was sent to), then mail will be lost or misdirected regardless
   of which software you use to access the mailbox. The mailbox cannot
   actually be said to be a domain mailbox in this case; the defining
   characteristic of a domain mailbox is that it records the envelope
   correctly. The configuration of the MTA running on the server needs to
   be fixed so that the envelope is properly recorded for every message
   it receives.
   
This rc stuff seems complicated. Does it have to be?

   The configuration file format is actually very simple; you don't need
   to worry about most of it if you're not interested in using those
   features. The simplest and most common getmail rc file configuration
   will be for users who want to retrieve all mail from a single-user
   POP3 mailbox, deliver those messages to a maildir or mbox file, and
   delete the mail from the server. For maildir, that configuration is:
[options]
delete = True

[retriever]
type = SimplePOP3Retriever
server = my-pop3-servername
username = my-pop3-username
password = my-pop3-password

[destination]
type = Maildir
path = ~/Maildir/

   For an mbox file, that configuration is:
[options]
delete = True

[retriever]
type = SimplePOP3Retriever
server = my-pop3-servername
username = my-pop3-username
password = my-pop3-password

[destination]
type = Mboxrd
path = ~/inbox

How do I ...

How do I retrieve mail from multiple accounts?

   Create a separate getmail rc file for each account, and run getmail
   with multiple --rcfile options.
   
How do I stop getmail adding a Delivered-To: header to messages?

   Use the delivered_to [options] parameter.
   
How do I stop getmail adding a Received: header to messages?

   Use the received [options] parameter.
   
How do I make getmail deliver messages by re-injecting with SMTP?

   You don't need to. getmail can deliver to maildirs, mboxrd files, or
   through arbitrary external MDAs.
   
   If you still think you need to, you can use getmail's external MDA
   support to do so.
   
How do I make getmail deliver messages to an mh folder?

   mh clients (and nmh, or "new mh" clients) include a command for
   delivering a message into your mh folder. In nmh, this command is
   called rcvstore. You use it as an external message delivery agent
   (MDA) with getmail's MDA_external destination. Ensure your
   $HOME/.mh_profile file is configured properly; getmail user Frankye
   Fattarelli suggests a line like the following is necessary to indicate
   the path to your mh mail root:
Path: Mail

   Then use MDA_external like this (which, after adjusting the path of
   the command to reflect your mh/nmh installation, should work with
   either mh or nmh):
[destination]
type = MDA_external
path = /usr/local/libexec/nmh/rcvstore
arguments = ("+inbox", )

   Thanks to Frankye Fattarelli for contributing this answer.
   
How do I run getmail in "daemon" mode?

   Use your system's cron utility to run getmail periodically if you wish
   to have mail retrieved automatically at intervals. This is precisely
   what cron is designed to do; there's no need to add special code to
   getmail to do this.
   
   With a reasonably standard system cron utility, a crontab(5) entry
   like the following will make getmail retrieve mail every hour:
0 * * * * /usr/local/bin/getmail --quiet

How do I make getmail stop after retrieving X messages so that the server
actually flushes deleted messages?

   Use the max_messages_per_session option to limit the number of
   messages getmail will process in a single session. Some users with
   flaky servers use this option to reduce the chances of seeing messages
   more than once if the server dies in mid-session.
   
How do I make getmail retrieve mail from Hotmail?

   Well, you could write a retriever that speaks Hotmail's proprietary,
   undocumented, and unsupported access protocol (or pay me to write
   one), or simply set up the POP3 proxy from the httpmail package, and
   have getmail retrieve mail from that POP3 proxy.
   
I'm using getmail. How do I make it ...

   These are supplementary questions I occasionally see about doing
   various things to enhance a getmail setup. The solution to many of
   them is to use a standard Unix technique of some sort to make the
   system behave in a certain manner, or otherwise change the behaviour
   of something that's actually outside of getmail proper.
   
I'm running getmail from cron. How do I temporarily stop it?

   Some people ask about temporarily stopping getmail from running from a
   cron job, possibly because the mail server is down and they don't want
   to see the warnings cron mails them.
   
   The easiest method is to comment out getmail from your crontab file:
    1. Run
$ crontab -e
       to edit your crontab file.
    2. Place a # (pound) character at the start of the line containing
       the call to getmail.
    3. Save the changed file.
       
   When you want to re-enable getmail, edit the file again and un-do the
   above change.
   
   If you need to do this on a regular basis, you can instead use a "flag
   file" to tell the system whether or not to run getmail:
   
   Change your cron job or shellscript that normally launches getmail to
   check for the presence of a certain file first, and have it not run
   getmail if that file is present. For example, your crontab entry could
   be changed to do this:
    [ -f ~/.getmail/do-not-run ] || /path/to/getmail

   When you don't want getmail to run, touch that file:
    $ touch ~/.getmail/do-not-run

   When you want getmail to run again, delete it:
    $ rm -f ~/.getmail/do-not-run

   This is even safe for scripting, as creating and removing the file are
   atomic operations under Unix.
   
How do I stop multiple instances of getmail from running at the same time?

   getmail has no problems running multiple instances in parallel, though
   you shouldn't attempt to use the same getmail rc file from two
   different instances at the same time. If you need to prevent two
   instances of getmail from running simultaneously, use any standard
   Unix method of providing a mutex for this purpose. One example would
   be to run getmail under a program like setlock (part of the
   daemontools package). Change your script or crontab file to invoke
   getmail like this:
/path/to/setlock -n /path/to/lockfile /path/to/getmail [getmail options]

   There are other programs that provide functionality similar to
   setlock.
   
Using getmail with other software

   getmail user Frankye Fattarelli contributed to the following questions
   about integrating getmail with SpamAssassin and ClamAV.
   
How do I use SpamAssassin with getmail?

   SpamAssassin can be run in standalone mode or in a client/server
   configuration. In both configurations, SpamAssassin accepts a wide
   variety of arguments; please refer to SpamAssassin's manual pages or
   online documentation for details.
   
   To filter messages through SpamAssassin in a client/server
   configuration (i.e. with the spamd daemon), use a configuration like
   this:
[filter]
type = Filter_external
path = /usr/local/bin/spamc
arguments = ("-s 10000", )

   The value supplied to the -s option is the maximum message size
   accepted (in bytes). The default is 250k.
   
   A similar configuration without the spamd daemon would be:
[filter]
type = Filter_external
path = /usr/local/bin/spamassassin
arguments = ("--report", )

   The --report option sends the message to the various spam-blocker
   databases and tags it as spam in your bayesian database.
   
   Note that if you are using Bayesian (learning) filtering, and you've
   put your SpamAssassin filter after any getmail Filter_classifier, you
   may have a problem with your learning filter learning getmail's header
   fields. That is, the headers added by the other filters may get
   learned, and affect your database. To prevent this, ensure that
   SpamAssassin ignores these fields by adding the following to your
   SpamAssassin configuration:
bayes_ignore_header X-getmail-filter-classifier

How do I use ClamAV with getmail?

   You should also read this message in the getmail users' mailing list
   archives and the ClamAV documentation if you want to use ClamAV with
   getmail.
   
   ClamAV, like SpamAssassin, can by used in standalone or client/server
   configurations. In either case, you need to add the StreamSaveToDisk
   option to your clamav.conf file to enable scanning from stdin.
   
   To use ClamAV without the clamd daemon, use a filter configuration
   like this:
[filter]
type = Filter_classifier
path = /usr/local/bin/clamscan
arguments = ("--stdout", "--no-summary",
    "--mbox", "--infected", "-")
exitcodes_drop = (1,)

   The above assumes you do not want the infected emails to be delivered.
   If you do want them delivered, you would use a slightly different
   configuration:
[filter]
type = Filter_classifier
path = /usr/local/bin/clamscan
arguments = ("--stdout", "--no-summary",
    "--mbox", "--infected", "-")
exitcodes_keep = (0,1)

   To use ClamAV with the clamd daemon, use a filter configuration like
   this:
[filter]
type = Filter_classifier
path = /usr/local/bin/clamdscan
arguments = ("--stdout", "--disable-summary", "-")
exitcodes_drop = (1, )

   As with Clamscan (above), if you do want the infected messages
   delivered instead of dropped, you should modify your configuration as
   follows:
[filter]
type = Filter_classifier
path = /usr/local/bin/clamdscan
arguments = ("--stdout", "--disable-summary", "-")
exitcodes_keep = (0,1)

   You may find it necessary to specify the paths of some decompression
   utilities used by ClamAV with additional arguments like:
arguments = ( ...,
    "--unzip=/usr/local/bin/unzip",
    "--unrar=/usr/local/bin/unrar",
    "--unarj=/usr/local/bin/unarj",
    "--lha=/usr/local/bin/lha",
    "--jar=/usr/local/bin/unzip",
    "--tar=/usr/bin/tar",
    "--tgz=/usr/bin/tar"

   Note: if you want to use the daemonized (client/server) version of
   ClamAV, ensure that your clamav.conf file contains:
ScanMail

   The paths to the various decompression utilities must be specified in
   this file as well.
   
   See the following mailing list message from Frankye Fattarelli for
   additional notes on using ClamAV with getmail:
   http://marc.theaimsgroup.com/?l=getmail&m=109128345509273&w=2
   
Getting prettier output from ClamAV

   Using getmail's Filter_classifier, the output of your filtering
   program (in this case ClamAV) is placed into a
   X-getmail-filter-classifier: header field in the message. This can
   make auditing the actions of filters difficult if you use multiple
   filters and cannot tell which filter added which line.
   
   To correct this, you can use an additional filter to change the name
   of the added filter header lines immediately after each filter is run.
   For example, reformail, from the maildrop package (which is in turn
   part of the Courier MTA ) can be used in this fashion to rename the
   added header fields (say, to "X-mypersonalmailscan") with a filter
   configuration like this:
type = Filter_external
path = /usr/local/bin/reformail
arguments = ("-R", "X-getmail-filter-classifier:",
    "X-mypersonalmailscan:")

   Simply ensure ClamAV is invoked as the first filter, and this is
   invoked as the second filter (or immediately after the ClamAV filter,
   if it is the second, third, etc. filter).
   
How do I use F-Prot with getmail?

   getmail user Kai Raven reports that getmail and F-Prot work fine
   together with the following getmailrc filter configuration:
[filter]
type = Filter_external

path = /usr/local/bin/f-prot-wrapper.sh

   The wrapper script f-prot-wrapper.sh is a small shellscript by Ali
   Onur Cinar, and can be downloaded from his website.
   
How do I use procmail with getmail?

   Simply invoke procmail as an external MDA. procmail requires that one
   of the following be true:
     * that the message begin with a Unix "From " line (the mbox message
       delimiter)
     * that procmail is invoked with the -f option supplying the envelope
       sender, so that it may generate the "From " line
       
   To have getmail generate and prepend the "From " line to the start of
   the message, set the MDA_external parameter unixfrom to True:
[destination]
type = MDA_external
path = /path/to/procmail
unixfrom = True

   To supply the -f option to procmail, do something like this:
[destination]
type = MDA_external
path = /path/to/procmail
arguments = ("-f", "%(sender)")

How do I use maildrop with getmail?

   Simply invoke maildrop as an external MDA. maildrop requires that the
   message begin with a Unix "From " line (the mbox message delimiter),
   so you'll need to either set the MDA_external parameter unixfrom to
   True, or supply arguments that tell maildrop to recreate this line.
   One of the following would be fine:
[destination]
type = MDA_external
path = /path/to/maildrop
arguments = ("-f", "%(sender)")

   Or:
[destination]
type = MDA_external
path = /path/to/maildrop
unixfrom = True

   If you want to specify a maildrop rc file as one of its arguments,
   that would be something like:
[destination]
type = MDA_external
path = /path/to/maildrop
arguments = ("-f", "%(sender)", "~/.maildroprc")

How do I use TMDA with getmail?

   Simply use the Filter_TMDA module as a message filter:
[filter-X]
type = Filter_TMDA

   See the documentation for details on optional parameters to the
   Filter_TMDA module.
   
I think I found this bug in getmail ...

   I get frequent reports like the following, which aren't bugs in
   getmail. Please read them before reporting them to me.
   
FutureWarning: %u/%o/%x/%X of negative int will return a signed string in
Python 2.4 and up

   Various people have reported this "bug" in getmail, where they see the
   following warning when getmail is run:
/usr/lib/python2.3/optparse.py:668: FutureWarning: %u/%o/%x/%X of negative int
will return a signed string in Python 2.4 and up
  return ("<%s at 0x%x: %r>"

   This warning is a bug in Python 2.3.4's optparse.py module, not in
   getmail. Feel free to report it to the Python team if the most recent
   release of Python hasn't fixed it. I reported it in June, 2004.
   
DeprecationWarning: 'strict' argument is deprecated (and ignored)

   Various people have reported this "bug" in getmail, where they see the
   following warning when getmail is run with Python version 2.4:
/usr/local/lib/python2.4/email/__init__.py:43: DeprecationWarning: 'strict' arg
ument is deprecated (and ignored)
  return Parser(*args, **kws).parsestr(s)
/usr/local/lib/python2.4/email/__init__.py:52: DeprecationWarning: 'strict' arg
ument is deprecated (and ignored)
  return Parser(*args, **kws).parse(fp)

   This is a warning (not an error). This likely should have been added
   in Python as a FutureWarning before it became a DeprecationWarning. In
   any case, getmail still needs to unset the strict option with earlier
   versions of Python. If you see this warning, and would like to disable
   it, you can add the option to the invocation of Python by changing the
   first line of the getmail script to be:
 #!/path/to/python2.4 -Wignore:.:DeprecationWarning:.:0

AttributeError: 'module' object has no attribute 'fsync'

   Various people have reported this "bug" in getmail -- it's actually a
   bug in some versions of Python 2.3.X. It was fixed in Python version
   2.3.3. getmail 4 detects problematic versions of Python and refuses to
   run, but you can still encounter this problem with getmail version 3
   if you try to run it with a broken Python version.
