# getmail Frequently Asked Questions (FAQ)

getmail6 is Copyright © 1998-2020 by Charles Cazabon and others:
<charlesc-getmail @ pyropus.ca>
<roland.puntaier @ gmail.com>

getmail is licensed under the GNU General Public License version 2 (only).

# Table of Contents

- getmail documentation
- - getmail documentation
  - - Features
    - Requirements
    - Obtaining getmail
    - Installing getmail
- getmail configuration (version 5)
- - Configuring getmail
  - - Creating a getmail rc file
  - Running getmail
  - - Commandline options
    - Using getmail as an MDA
    - Using getmail_fetch to retrieve mail from scripts
- getmail troubleshooting
- - Troubleshooting problems
  - - Error messages
    - Warning messages
    - Unexpected Behaviour
- getmail frequently-asked questions (FAQs)
- - Frequently-Asked Questions (FAQs)
  - - About getmail
    - - What is getmail?
      - What is getmail6 and how does it relate to getmail?
      - What platforms/machines does getmail run on?
      - - Does getmail run on MS Windows?
        - Does getmail run on Macintosh systems?
        - Does getmail require Unix/Linux?
      - How can I get support for getmail?
      - I think I found a bug! How do I report it?
      - I have a neat idea for random feature "foo" … how do I get you to implement it?
      - Why won't you implement random feature "foo"?
      - Does getmail support virus scanning of retrieved messages?
      - Does getmail support spam filtering of retrieved messages?
      - Does getmail support SSL?
      - Does getmail rewrite mail headers when it retrieves mail?
      - What are these oldmail* files? Can I delete or trim them?
      - Can I upgrade from getmail 3 to getmail 4/5? What about my "oldmail" files?
      - Why did you write getmail? Why not just use fetchmail?
    - Configuring getmail
    - - What is a "domain mailbox"?
      - Do I have to run sendmail or another MTA to use getmail?
      - Will getmail deliver mail as root?
      - What's a maildir?
      - What's "mboxrd" format?
      - What's this "envelope sender" and "envelope recipient" stuff?
      - - Message header vs. message envelope
        - Receiving messages without your address in the message header
        - Responsibility for recording the message envelope
        - How this relates to domain or multidrop mailboxes
      - This rc stuff seems complicated. Does it have to be?
    - How do I …
    - - How do I retrieve mail from multiple accounts?
      - How do I get getmail to deliver messages to different mailboxes based on …
      - How do I stop getmail adding a Delivered-To: header to messages?
      - How do I stop getmail adding a Received: header to messages?
      - How do I make getmail deliver messages by re-injecting with SMTP?
      - How do I create a maildir?
      - How do I create an mboxrd file?
      - How do I make getmail deliver messages to an mh folder?
      - How do I run getmail in "daemon" mode?
      - How do I make getmail stop after retrieving X messages so that the server actually flushes deleted messages?
      - How do I make getmail retrieve mail from Hotmail?
      - I'm using getmail. How do I make it …
      - - I'm running getmail from cron. How do I temporarily stop it?
        - How do I stop multiple instances of getmail from running at the same time?
    - Using getmail with other software
    - - How do I use SpamAssassin with getmail?
      - How do I use ClamAV with getmail?
      - - Getting prettier output from ClamAV
      - How do I use F-Prot with getmail?
      - How do I use procmail with getmail?
      - How do I use maildrop with getmail?
      - How do I use TMDA with getmail?
      - - How can I get Gmail labels with getmail?
    - I think I found this bug in getmail …
    - - getmail doesn't download all my mail from Gmail …
      - FutureWarning: %u/%o/%x/%X of negative int will return a signed string in Python 2.4 and up
      - AttributeError: 'module' object has no attribute 'fsync'
      - operation error (SimplePOP3Retriever: [...] does not uniquely identify messages [...] see documentation or use BrokenUIDLPOP3Retriever instead
      - MemoryError on OS X
      - MemoryError when using IMAP
      - Errors connecting to Gmail with OpenSSL 1.1.1

# Frequently-Asked Questions (FAQs)

The following questions about getmail have been asked 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 is getmail6 and how does it relate to getmail?

getmail is the name of this software and project as it was originally developed by Charles Cazabon. At the time of getmail version 5.14 getmail would not work with Python version 3 and newer. As support for Python 3 was not available for getmail at the time while many distributions were dropping support for all Python versions older than version 3, this fork was created.

To avoid confusion and conflicts with Charles' project, we decided to call our fork getmail6 and start our version numbering from 6.

As we intend getmail6 to be a drop-in replacement for getmail, names of files etc. have been kept the same as they are in getmail 5.14 and earlier.

### 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, we will do our best to support getmail on a voluntary basis through our GitHub repository.

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, please open an issue on GitHub. If you post your question there, we will see it.

### 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://getmail6.org/.
If you are running an older version of the software, chances are whatever bug you may have found has already been fixed.

After this, please check our repository on GitHub to see if this issue has already been reported. If not, feel free to open an issue to report your bug. You should include at least 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 your bugreport contains confidential information, please exclude this from your report.

### 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 we would prefer you submit your idea as an issue in our repository allowing other users to also comment on it which may 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. We 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 us.

If you have asked me to add some feature, and we've said no, this may be the reason. Other possibilities include us 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.

### What are these oldmail* files? Can I delete or trim them?

getmail stores its state - its "memory" of what it has seen in your POP/IMAP account - in the oldmail files.

Do NOT delete or edit these files. You'll make getmail re-retrieve all your old mail, or even prevent getmail from running. The files are tiny by modern storage standards; you could have a million of these files and still not have to worry about the disk space they take up for a thousand years.

### Why did you write getmail? Why not just use fetchmail?

The below text is by Charles Cazabon, getmail's original author:

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 .
- Just in case you thought fetchmail was all better now, there's still new security problems being discovered in it. In December, 2005, it was revealed that anyone can send a fetchmail multidrop user a message that causes fetchmail to crash.

In July, 2004, it was noted that 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 others have noted continuing problems, including:

- another arbitrary code execution vulnerability announced on 21 July 2005.

The fetchmail authors' boneheaded decision to create a configuration-file GUI editor (rather than actually giving fetchmail a sane configuration syntax) also came back to bite them in the ass: in October 2005, it became known that fetchmailconf created its files in such a way that users' passwords could be read during file creation.

Addendum, January 2007: since I wrote the above, the following new security problems have been discovered in fetchmail:

- CVE-2005-4348 - anyone can crash fetchmail by sending messages without headers
- CVE-2006-0321 - anyone can crash fetchmail by sending a message that fetchmail tries to bounce
- CVE-2006-5867 - fetchmail can transmit passwords in plaintext even if the user has configured it not to
- CVE-2006-5974 - anyone can cause fetchmail to crash by triggering certain error code paths

But don't just take my word for it; see http://docs.freebsd.org/cgi/mid.cgi?200102172349.QAA11724 and http://esr.1accesshost.com/ (note: went offline sometime in 2009 or 2010; the content is still available at http://web.archive.org/web/20080621090439/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.

Of course, it's really easy to script this for a large number of rc-* files. You might create a script in $HOME/bin/run-getmail.sh containing:

    #!/bin/sh
    set -e
    cd /path/to/my-rc-directory
    rcfiles=""
    for file in rc-* ; do
      rcfiles="$rcfiles --rcfile $file"
    done
    exec /path/to/getmail $rcfiles $@

See any beginner's tutorial on Unix shell scripting for details.

### How do I get getmail to deliver messages to different mailboxes based on …

If you want getmail to sort messages based on who they're from, or what address appears in the To: or cc: header fields, or based on the Subject: field contents, or anything like that, pick a filtering MDA (like maildrop or procmail), and call it from a getmail MDA_external destination.

### 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 create a maildir?

Use the maildirmake command, if you have it installed. Otherwise, run the following command from your shell:

    $ mkdir -p /path/to/Maildir/{cur,new,tmp}

Some other maildir-aware programs ship with their own maildir-creation programs; you can use those, or make the above shell command a shellscript or alias if you like.

### How do I create an mboxrd file?

Create a completely empty (i.e. zero bytes long) file via your favourite method. The standard utility touch is commonly used:

    $ touch /path/to/mboxrd

### 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?

getmail does not have, and does not need, any special "daemon mode". You just run getmail under whatever process-supervision or periodic-job system you already have on your system.

For example, if you use daemontools/svscan/supervise, you can configure a getmail "service" using a simple run script like:

    #!/bin/sh

    /path/to/getmail [options]
    sleep 1800

That example would run getmail continuously, sleeping for 30 minutes between runs. You can probably work out similar scripts for other process-supervision systems.

If you don't have such a system, you can use your system's cron utility to run getmail periodically, but you absolutely have to prevent multiple copies of getmail from being run by cron simultaneously. Most versions of cron have no protection for this built-in, so you have to use setlock or flock or a similar utility to prevent it. For more details, see How do I stop multiple instances of getmail from running at the same time? below. If you do not prevent multiple copies of getmail running against the same server (and IMAP folder) simultaneously, you will get odd behaviour, including retrieving the same messages multiple times.

### 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 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; it will probably cause getmail to deliver duplicate copies of messages, "forget" that it has seen particular messages before, and other similar problems.

In particular, if you're running getmail from a crontab, you must do something to prevent cron from starting getmail if the previous invocation is still running.

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: https://marc.info/?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.

#### How can I get Gmail labels with getmail?

As of getmail version 4.34.0, getmail retrieves the labels and other metadata that Gmail makes available via an IMAP extension, and records that information in the message headers X-GMAIL-LABELS:, X-GMAIL-THRID:, and X-GMAIL-MSGID:.

## I think I found this bug in getmail …

There are frequent reports like the following, which aren't bugs in getmail. Please read them before reporting them as bugs.

### getmail doesn't download all my mail from Gmail …

There's a couple of different problems here. One is that Google's Gmail service violates the POP3 protocol by removing messages from the POP3 view of the mailbox without the user issuing a DELE command. They do this as soon as an RETR command is given, so if getmail tries to download a message and it fails for any reason (delivery fails due to a full disk, or the Gmail server fails to respond, or the network connection dies before the transfer is complete, or the Gmail server fails to respond to the QUIT command, or …), the next time getmail connects to that Gmail account, Gmail will have "helpfully" deleted the message from the POP3 mailbox, even though getmail never issued a DELE command. So Gmail silently destroys mail, from a POP3 perspective. There's nothing getmail can do about this.

Note this feature of Gmail is not well-publicized. The only mention I can find of it is here: http://mail.google.com/support/bin/answer.py?answer=13291&topic=1555

The other issue here is that Google doesn't include mail from your trash or spam folders in the POP3 view, so getmail can't see those messages either. That's generally less of an issue, provided their spam filters never give false positive results (ha!).

### operation error (SimplePOP3Retriever: [...] does not uniquely identify messages [...] see documentation or use BrokenUIDLPOP3Retriever instead

The server you're trying to use does not properly uniquely identify messages (getmail noticed when it saw the same "unique" identifier twice in the same mailbox at the same time). getmail needs these identifiers to be unique so that it can properly tell the difference between new and old messages.

If you see this error message, and you've configured getmail to retrieve and immediately delete all messages, just switch to using the BrokenUIDLPOP3Retriever class (or its SSL variant) -- it'll work fine.

If you see this error message, and you're trying to leave messages on the server after retrieval (permanently, or for a few days with delete_after), you have a few options to try to resolve it:

- If your provider also offers IMAP access to your mailbox, try one of the IMAP retrievers instead.
- Change your configuration so you're not leaving messages on the server, and use BrokenUIDLPOP3Retriever instead.
- Talk to your mail hosting provider, and see if they can fix their POP3 software so that it doesn't have this problem any more.

### MemoryError on OS X

If you see errors like this while running getmail on Macintosh OS X:

    python2.5(27172) malloc: *** vm_allocate(size=15699968) failed (error code=3)
    python2.5(27172) malloc: *** error: can't allocate region
    python2.5(27172) malloc: *** set a breakpoint in szone_error to debug
    [...]

... which then end with MemoryError, please report the problem to Apple. The OS X implementation of realloc() is broken, and there's nothing getmail can do about it.

### Errors connecting to Gmail with OpenSSL 1.1.1

If you experience connection/SSL errors connecting to Gmail servers, and your OpenSSL is version 1.1.1 or higher, the problem is that Gmail is failing the connection on the basis that SNI is not in use. To work around the problem, upgrade to getmail v.5.10 or later, or tell getmail to use TLSv1.2 rather than TLS1.3 in your retriever configuration and specify TLS v1.2 as the protocol to use:

    [retriever]
    ...
    ssl_version = tlsv1_2