Mutt

IMAP[edit | edit source]

The imap USE flag is probably the most important feature to enable for Mutt. Enabling it only beneficial. Most email providers, even free ones such as Gmail, use IMAP, as it is the most convenient way to store email that is accessed from multiple clients at the same time and/or different locations. Because IMAP keeps all mail at the server, Mutt just downloads the messages that you want to view.

Header cache backends[edit | edit source]

Next to reading messages, it often happens that you will list a mailbox, to see what is in there. For this information, Mutt has to download the message headers. When you switch folders frequently, or your folders contain a large amount of emails, downloading the message headers over and over again will take some time. Since this simply is a waste, Mutt uses a so-called header cache (USE flag hcache) to keep the most important bits of messages that it needs to greatly speedup opening folders. This header cache is backed by a db-library, of which five flavours exist: berkdb, gdbm, lmdb, qdbm, and tokyocabinet. If you don't have any preference yourself, pick lmdb as it is the fastest when used with Mutt. You can only enable at most one db-library USE flag for hcache backend. If you re-emerge Mutt with a different db-library later, Mutt will rebuild its caches automatically when it opens a folder.

Sending mail[edit | edit source]

While IMAP is important for reading mail, sending mail requires a mail server. Mutt can deliver mail using a local (send)mail submission, but often that's not a good solution for users that travel around (e.g. laptop users). Mutt comes with SMTP support which is enabled by default with the smtp USE flag. Mutt's SMTP support allows you to send mail over a mail server of your choice with the option to authenticate an account. This is usually an SMTP server given to you by the email provider.

Secure protocols[edit | edit source]

Both IMAP and SMTP protocols send data over encrypted channels. With the imap and/or smtp USE flags enabled, it is wise to enable the ssl or gnutls USE flags. Both add the secure variants (imaps and smtps) to Mutt's list of supported protocols using either OpenSSL's or GNUTLS' implementation respectively. Most readers will not have a strong preference between OpenSSL and GNUTLS, so just go for ssl, since it is most likely this is already in the system's global list of USE flags. When intending to authenticate when sending e-mail, be sure to also include the sasl USE flag. The sasl USE flag is required for authentication when sending email.

Encryption[edit | edit source]

Even with secure IMAPS and SMTPS protocols, it is best practice to sign and/or encrypt email messages. Mutt supports traditional OpenPGP and S/MIME. Both of these are supported using the gpgme wrapper. The easiest way to setup support for signed and encrypted messages is using the gpgme USE flag. Documentation and experiences in this area can be confusing to say the least. When enabling gpgme USE flag, ensure the backend has been properly setup in the configuration (see below).

.muttrc[edit | edit source]

# character set on sent messages
set send_charset="utf-8"
# if there is no character set given on incoming messages, it is probably windows
set assumed_charset="iso-8859-1"
  
# make sure Vim knows Mutt is a mail client and that a UTF-8 encoded message will be composed
set editor="vim -c 'set syntax=mail ft=mail enc=utf-8'"
  
# just scroll one line instead of full page
set menu_scroll=yes
  
# we want to see some MIME types inline, see below this code listing for explanation
auto_view application/msword
auto_view application/pdf
  
# make default search pattern to search in To, Cc and Subject
set simple_search="~f %s | ~C %s | ~s %s"
  
# threading preferences, sort by threads
set sort=threads
set strict_threads=yes
  
# show spam score (from SpamAssassin only) when reading a message
spam "X-Spam-Score: ([0-9\\.]+).*" "SA: %1"
set pager_format = " %C - %[%H:%M] %.20v, %s%* %?H? [%H] ?"
  
# do not show all headers, just a few
ignore          *
unignore        From To Cc Bcc Date Subject
# and in this order
unhdr_order     *
hdr_order       From: To: Cc: Bcc: Date: Subject:
  
# brighten up stuff with colors, for more coloring examples see:
# http://aperiodic.net/phil/configs/mutt/colors
color normal      white          black
color hdrdefault  green          default
color quoted      green          default
color quoted1     yellow         default
color quoted2     red            default
color signature   cyan           default
color indicator   brightyellow   red
color error       brightred      default
color status      brightwhite    blue
color tree        brightmagenta  black
color tilde       blue           default
color attachment  brightyellow   default
color markers     brightred      default
color message     white          black
color search      brightwhite    magenta
color bold        brightyellow   default
# if you don't like the black progress bar at the bottom of the screen,
# comment out the following line
color progress    white          black
  
# personality settings
set realname = "Larry the cow"
set from = "larry@mail.server"
alternates "larry@mail.server|larry.the.cow@mail.server"
# this file must exist, and contains your signature, comment it out if
# you don't want a signature to be used
set signature = ~/.signature
  
# aliases (sort of address book)
source ~/.aliases
  
# IMAP connection settings
set mail_check=60
set imap_keepalive=300
  
# IMAP account settings
set folder=imaps://larry@imap.mail.server/
set spoolfile=imaps://larry@imap.mail.server/
set record=imaps://larry@imap.mail.server/Sent
set postponed=imaps://larry@imap.mail.server/Drafts
  
# use headercache for IMAP (make sure this is a directory for better performance!)
set header_cache=/var/tmp/.mutt
 
# uncomment this to enable the sidebar feature
#set sidebar_visible = yes
set sidebar_width = 15
set sidebar_folder_indent = yes
set sidebar_short_path = yes
 
# make the progress updates not that expensive, this will update the bar every 300ms
set read_inc = 1
set time_inc = 300
 
# only if you compiled Mutt with USE=gpgme, enable the gpgme backend
set crypt_use_gpgme = yes
# you can set this to hide gpg's verification output and only rely on Mutt's status flag
#set crypt_display_signature = no
# enable signing of emails by default
set pgp_autosign = yes
set pgp_sign_as = 0xXXXXXXXX   # your gpg keyid here
set pgp_replyencrypt = yes
 
# mailboxes we want to monitor for new mail
mailboxes "="
mailboxes "=Lists"
  
# mailing lists for a Gentoo user (these are regexps!)
subscribe "gentoo-.*@gentoo\\.org"
  
# SMTP mailing configuration (for sending mail)
set smtp_url=smtp://larry@mail.server/

The example .muttrc above sets up an IMAP account, uses an SMTP server to send mail, stores its cache in /var/tmp/.mutt, reads the known address aliases (think of it as an address book) from ~/.aliases and appends the signature from ~/.signature when composing new mail. For some IMAP servers it may be necessary to change the spool, record and postponed directories, as the folders Sent and Drafts may be under a folder called INBOX. Simply trying this out with Mutt is the simplest way to figure this out.

Once the .muttrc is setup, you are ready to launch Mutt by just running mutt. If you entered a valid IMAP server URL, Mutt will prompt for a password and afterwards load all messages. Note that the first time entering your mailbox may take a while if you have quite some messages, since Mutt's header cache is still empty. If this succeeds you're in your IMAP mailbox ready to go.

Navigation is intuitive, as is reading messages by just pressing the Enter key or Space bar. Mutt is quite Vim alike in that it uses key strokes to perform most of its actions. You best read Mutt's manual to become familiar with all existing functions (or press ? in Mutt) and what key they are bound to, or better, what key you like it to be bound to. Some essential keys are m (for message) to start composing a new message, q for quit, r for reply, s for save and p for print.

.mailcap[edit | edit source]

One of the features that Mutt has that is still not in today's most savvy email clients is the ability to display attachments inline through some viewer. The auto_view directive in the .muttrc file tells Mutt which attachments (based on their MIME-type) it should view inline. To figure out how to do that, Mutt uses mailcap files to lookup how to display a certain MIME-type. Usually the system wide mailcap file isn't sufficient here, so you better start a ~/.mailcap file to put items in there for copiousoutput that Mutt can display inline.

In the example .muttrc above auto_view is enabled for application/msword and application/pdf files. These two show the extreme usefulness of this capability, because it means meeting notes sent as doc file now are perfectly fine readable without having to save the attachment and open it in LibreOffice. Instead the text just shows up in the message reader, that is, if you have a matching entry in your ~/.mailcap file.

application/msword; antiword '%s'; copiousoutput; description=Word Document;
nametemplate=%s.doc
application/pdf; pdftotext '%s' -; copiousoutput; description=PDF Document;
nametemplate=%s.pdf

The above .mailcap example tells Mutt what to do to "view" msword and pdf files. For the former it should run a program called antiword (emerge app-text/antiword), for the latter the program pdftotext (emerge app-text/poppler). You can go wild with these to for example display rendered HTML (give app-text/vilistextum a try), render vcards, or show ASCII representation of attached images. All you need to do is define how to call the program in your .mailcap, and tell Mutt to try to view it inline using the auto_view directive.