docker-offlineimap/manual.txt

OFFLINEIMAP(1)                OfflineIMAP Manual                OFFLINEIMAP(1)



NAME
       OfflineIMAP - Powerful IMAP/Maildir synchronization and reader support

SYNOPSIS
       offlineimap [ -1 ] [ -P profiledir ] [ -a accountlist ] [ -c configfile
       ] [ -d debugtype[,...] ] [ -l filename ] [ -o ] [ -u interface ]


       offlineimap -h | --help


DESCRIPTION
       OfflineIMAP is  a  tool  to   simplify   your   e-mail  reading.   With
       OfflineIMAP,  you  can  read  the same mailbox from multiple computers.
       You get a current copy of your messages on each computer,  and  changes
       you make one place will be visible on all other systems.  For instance,
       you can delete a message on your home  computer,  and  it  will  appear
       deleted  on  your work computer as well.  OfflineIMAP is also useful if
       you want to use a mail reader that does not have IMAP support, has poor
       IMAP support, or does not provide disconnected operation.

       OfflineIMAP is FAST; it synchronizes my two accounts with over 50 fold-
       ers in 3 seconds.  Other similar tools might take over  a  minute,  and
       achieve  a  less-reliable  result.   Some mail readers can take over 10
       minutes to do the same thing, and some don't even support  it  at  all.
       Unlike other mail tools, OfflineIMAP features a multi-threaded synchro-
       nization algorithm that can dramatically speed up performance  in  many
       situations by synchronizing several different things simultaneously.

       OfflineIMAP is FLEXIBLE; you can customize which folders are synced via
       regular expressions, lists, or Python expressions; a versatile and com-
       prehensive  configuration  file  is  used to control behavior; two user
       interfaces are built-in; fine-tuning of synchronization performance  is
       possible; internal or external automation is supported; SSL and PREAUTH
       tunnels are both supported; offline (or "unplugged")  reading  is  sup-
       ported;  and esoteric IMAP features are supported to ensure compatibil-
       ity with the widest variety of IMAP servers.

       OfflineIMAP is SAFE; it uses an algorithm designed to prevent mail loss
       at  all  costs.  Because of the design of this algorithm, even program-
       ming errors should not result in loss of mail.  I am  so  confident  in
       the  algorithm that I use my own personal and work accounts for testing
       of OfflineIMAP pre-release, development, and beta releases.  Of course,
       legally  speaking,  OfflineIMAP  comes  with  no  warranty, so I am not
       responsible if this turns out to be wrong.

   METHOD OF OPERATION
       OfflineIMAP traditionally operates by maintaining a hierarchy  of  mail
       folders in Maildir format locally.  Your own mail reader will read mail
       from this tree, and need never know that  the  mail  comes  from  IMAP.
       OfflineIMAP will detect changes to the mail folders on your IMAP server
       and your own computer and bi-directionally synchronize  them,  copying,
       marking, and deleting messages as necessary.

       With OfflineIMAP 4.0, a powerful new ability has been introduced -- the
       program can now synchronize two IMAP servers with each other,  with  no
       need  to have a Maildir layer in-between.  Many people use this if they
       use a mail  reader  on  their  local  machine  that  does  not  support
       Maildirs.   People  may  install an IMAP server on their local machine,
       and point both OfflineIMAP and their mail reader of choice at it.  This
       is  often  preferable  to  the  mail  reader's  own  IMAP support since
       OfflineIMAP supports many features (offline reading, for one) that most
       IMAP-aware  readers don't.  However, this feature is not as time-tested
       as traditional syncing, so my advice is to stick with normal methods of
       operation for the time being.

QUICK START
       If  you  have already installed OfflineIMAP system-wide, or your system
       administrator  has  done  that  for  you,  your  task  for  setting  up
       OfflineIMAP  for  the first time is quite simple.  You just need to set
       up your configuration file, make your folder directory, and run it!

       You can quickly set  up  your  configuration  file.   The  distribution
       includes a file offlineimap.conf.minimal (Debian users may find this at
       /usr/share/doc/offlineimap/examples/offlineimap.conf.minimal) that is a
       basic example of setting of OfflineIMAP.  You can simply copy this file
       into your home directory and name it .offlineimaprc (note  the  leading
       period).     A    command    such    as   cp   offlineimap.conf.minimal
       ~/.offlineimaprc will do it.  Or, if you prefer, you can just copy this
       text to ~/.offlineimaprc:

       [general]
       accounts = Test

       [Account Test]
       localrepository = Local
       remoterepository = Remote

       [Repository Local]
       type = Maildir
       localfolders = ~/Test

       [Repository Remote]
       type = IMAP
       remotehost = examplehost
       remoteuser = jgoerzen

       Now, edit the ~/.offlineimaprc file with your favorite editor.  All you
       have to do is specify a directory for your folders to  be  in  (on  the
       localfolders  line),  the host name of your IMAP server (on the remote-
       host line), and your login name on the remote (on the remoteuser line).
       That's it!

       To  run  OfflineIMAP,  you just have to say offlineimap -- it will fire
       up, ask you for a login password if necessary, synchronize  your  fold-
       ers,  and exit.  See?  You can just throw away the rest of this finely-
       crafted, perfectly-honed manual!  Of course, if you want to see how you
       can make OfflineIMAP FIVE TIMES FASTER FOR JUST $19.95 (err, well, $0),
       you have to read on!

INSTALLATION
       If you are reading this document via the "man" command,  it  is  likely
       that you have no installation tasks to perform; your system administra-
       tor has already installed it.  If you need to install it yourself,  you
       have three options: a system-wide installation with Debian, system-wide
       installation with other systems, and a single-user  installation.   You
       can  download  the  latest  version of OfflineIMAP from the OfflineIMAP
       website <URL:http://quux.org/devel/offlineimap/>.

   PREREQUISITES
       In order to use OfflineIMAP, you need to have these  conditions  satis-
       fied:

       o Your  mail server must support IMAP.  Most Internet Service Providers
         and corporate networks do, and most operating systems  have  an  IMAP
         implementation readily available.

       o You  must  have  Python version 2.2.1 or above installed.  If you are
         running on Debian GNU/Linux, this requirement will  automatically  be
         taken care of for you.  If you do not have Python already, check with
         your system administrator or operating system vendor; or, download it
         from  the Python website <URL:http://www.python.org/>.  If you intend
         to use the Tk interface, you must have Tkinter (python-tk) installed.
         If  you  intend  to use the SSL interface, your Python must have been
         built with SSL support.

       o Have a mail reader that supports the Maildir  mailbox  format.   Most
         modern  mail  readers  have  this support built-in, so you can choose
         from a wide variety of mail servers.  This format is  also  known  as
         the  "qmail"  format, so any mail reader compatible with it will work
         with OfflineIMAP.  If you do not have a  mail  reader  that  supports
         Maildir,  you  can  often  install a local IMAP server and point both
         OfflineIMAP and your mail reader at it.

   SYSTEM-WIDE INSTALLATION, DEBIAN
       If you are tracking Debian unstable, you  may  install  OfflineIMAP  by
       simply running the following command as root:

       apt-get install offlineimap

       If you are not tracking Debian unstable, download the Debian .deb pack-
       age          from           the           OfflineIMAP           website
       <URL:http://quux.org/devel/offlineimap/>   and  then  run  dpkg  -i  to
       install the downloaded package.  Then, skip to [XRef to  CONFIGURATION]
       below.  You will type offlineimap to invoke the program.

   SYSTEM-WIDE INSTALLATION, OTHER
       Download   the   tar.gz   version  of  the  package  from  the  website
       <URL:http://quux.org/devel/offlineimap/>.   Then  run  these  commands,
       making sure that you are the "root" user first:

       tar -zxvf offlineimap_x.y.z.tar.gz
       cd offlineimap-x.y.z
       python2.2 setup.py install

       On  some  systems,  you  will  need to use python instead of python2.2.
       Next,  proceed  to  [XRef  to  CONFIGURATION]  below.   You  will  type
       offlineimap to invoke the program.

   SINGLE-ACCOUNT INSTALLATION
       Download   the   tar.gz   version  of  the  package  from  the  website
       <URL:http://quux.org/devel/offlineimap/>.  Then run these commands:

       tar -zxvf offlineimap_x.y.z.tar.gz
       cd offlineimap-x.y.z

       When you want to run OfflineIMAP, you will  issue  the  cd  command  as
       above  and  then  type  ./offlineimap.py; there is no installation step
       necessary.

CONFIGURATION
       OfflineIMAP is regulated by  a  configuration  file  that  is  normally
       stored  in  ~/.offlineimaprc.   OfflineIMAP  ships  with  a  file named
       offlineimap.conf that you should copy to that location and  then  edit.
       This  file  is  vital to proper operation of the system; it sets every-
       thing you need to run OfflineIMAP.  Full documentation for the configu-
       ration file is included within the sample file.

       OfflineIMAP  also  ships a file named offlineimap.conf.minimal that you
       can also try.  It's useful if you want to get  started  with  the  most
       basic  feature  set,  and  you can read about other features later with
       offlineimap.conf.

OPTIONS
       Most configuration is done via the configuration  file.   Nevertheless,
       there  are a few command-line options that you may set for OfflineIMAP.

       -1     Disable most multithreading operations and use solely a  single-
              connection  sync.  This effectively sets the maxsyncaccounts and
              all maxconnections configuration file variables to 1.

       -P profiledir
              Sets OfflineIMAP into profile mode.   The  program  will  create
              profiledir (it must not already exist).  As it runs, Python pro-
              filing information about each thread is logged into  profiledir.
              Please  note: This option is present for debugging and optimiza-
              tion only, and should NOT be used unless  you  have  a  specific
              reason  to  do  so.   It will significantly slow program perfor-
              mance, may reduce reliability, and can generate huge amounts  of
              data.  You must use the -1 option when you use -P.

       -a accountlist
              Overrides the accounts option in the general section of the con-
              figuration  file.   You  might  use  this  to  exclude   certain
              accounts,  or to sync some accounts that you normally prefer not
              to.  Separate the  accounts  by  commas,  and  use  no  embedded
              spaces.

       -c configfile
              Specifies  a  configuration  file to use in lieu of the default,
              ~/.offlineimaprc.

       -d debugtype[,...]
              Enables debugging for OfflineIMAP.  This is useful  if  you  are
              trying  to  track down a malfunction or figure out what is going
              on under the hood.  I suggest that you use this with -1 to  make
              the results more sensible.

              -d  requires one or more debugtypes, separated by commas.  These
              define what exactly will be debugged, and include three options:
              imap,  maildir,  and  thread.   The imap option will enable IMAP
              protocol stream and parsing debugging.  Note that the output may
              contain  passwords,  so take care to remove that from the debug-
              ging output before sending  it  to  anyone  else.   The  maildir
              option  will  enable  debugging  for certain Maildir operations.
              And thread will debug the threading model.

       -l filename
              Enables logging to filename.  This will log everything that goes
              to  the  screen  to  the  specified  file.  Additionally, if any
              debugging is specified with -d, then debug messages will not  go
              to the screen, but instead to the logfile only.

       -o     Run only once, ignoring all autorefresh settings in the configu-
              ration file.

       -h

       --help Show summary of options.

       -u interface
              Specifies an alternative user interface  module  to  use.   This
              overrides  the default specified in the configuration file.  The
              pre-defined options are listed in the User Interfaces section.

USER INTERFACES
       OfflineIMAP has a pluggable user interface system that lets you  choose
       how the program communicates information to you.  There are two graphi-
       cal interfaces, two terminal interfaces, and two noninteractive  inter-
       faces suitable for scripting or logging purposes.  The ui option in the
       configuration file specifies user interface preferences.  The  -u  com-
       mand-line  option  can  override  the  configuration file setting.  The
       available  values  for  the  configuration  file  or  command-line  are
       described in this section.

   TK.BLINKENLIGHTS
       Tk.Blinkenlights  is  an  interface designed to be sleek, fun to watch,
       and informative of the overall picture of what OfflineIMAP is doing.  I
       consider it to be the best general-purpose interface in OfflineIMAP.

       Tk.Blinkenlights  contains,  by  default,  a small window with a row of
       LEDs, a small log, and a row of command buttons.  The total size of the
       window  is very small, so it uses little desktop space, yet it is quite
       functional.  The optional, toggleable, log shows more detail about what
       is happening and is color-coded to match the color of the lights.

       Tk.Blinkenlights  is  the  only  user  interface  that has configurable
       parameters; see the example offlineimap.conf for more details.

       Each light in the Blinkenlights interface represents a thread of execu-
       tion -- that is, a particular task that OfflineIMAP is performing right
       now.  The colors indicate what task the particular thread  is  perform-
       ing, and are as follows:

       Black  indicates that this light's thread has terminated; it will light
              up again later when new threads start up.  So,  black  indicates
              no activity.

       Red (Meaning 1)
              is  the color of the main program's thread, which basically does
              nothing but monitor the others.  It might remind you of HAL 9000
              in 2001.

       Gray   indicates  that  the  thread is establishing a new connection to
              the IMAP server.

       Purple is the color of an account synchronization thread that is  moni-
              toring the progress of the folders in that account (not generat-
              ing any I/O).

       Cyan   indicates that the thread is syncing a folder.

       Green  means that a folder's message list is being loaded.

       Blue   is the color of a message synchronization controller thread.

       Orange indicates that an actual message is being copied.  (We use fuch-
              sia for fake messages.)

       Red (meaning 2)
              indicates that a message is being deleted.

       Yellow / bright orange
              indicates that message flags are being added.

       Pink / bright red
              indicates that message flags are being removed.

       Red / Black Flashing
              corresponds  to  the  countdown timer that runs between synchro-
              nizations.

       The name of this interfaces derives from a  bit  of  computer  history.
       Eric Raymond's Jargon File defines blinkenlights, in part, as:


              Front-panel  diagnostic  lights  on a computer, esp. a dinosaur.
              Now that dinosaurs are rare, this term usually refers to  status
              lights on a modem, network hub, or the like.

              This  term derives from the last word of the famous blackletter-
              Gothic sign in mangled pseudo-German that once graced about half
              the  computer  rooms  in the English-speaking world. One version
              ran in its entirety as follows:

              ACHTUNG!  ALLES LOOKENSPEEPERS!

              Das computermachine ist nicht  fuer  gefingerpoken  und  mitten-
              grabben.   Ist  easy schnappen der springenwerk, blowenfusen und
              poppencorken mit spitzensparken.  Ist nicht  fuer  gewerken  bei
              das dumpkopfen.  Das rubbernecken sichtseeren keepen das cotten-
              pickenen hans in das  pockets  muss;  relaxen  und  watchen  das
              blinkenlichten.

   CURSES.BLINKENLIGHTS
       Curses.Blinkenlights  is an interface very similar to Tk.Blinkenlights,
       but is designed to be run in a console window (an xterm, Linux  virtual
       terminal,  etc.)   Since  it  doesn't have access to graphics, it isn't
       quite as pretty, but it still gets the job done.

       Please see the Tk.Blinkenlights  section  above  for  more  information
       about the colors used in this interface.

   TK.VERBOSEUI
       Tk.VerboseUI  (formerly known as Tk.TkUI) is a graphical interface that
       presents a variable-sized window.  In the window,  each  currently-exe-
       cuting  thread has a section where its name and current status are dis-
       played.  This interface is best suited to people running on slower con-
       nections,  as  you  get  a lot of detail, but for fast connections, the
       detail may go by too quickly to be useful.  People  with  fast  connec-
       tions may wish to use Tk.Blinkenlights instead.

   TTY.TTYUI
       TTY.TTYUI  interface  is  for people running in basic, non-color termi-
       nals.  It prints out basic status messages and is generally friendly to
       use on a console or xterm.

   NONINTERACTIVE.BASIC
       Noninteractive.Basic  is  designed  for situations in which OfflineIMAP
       will be run non-attended and  the  status  of  its  execution  will  be
       logged.   You  might use it, for instance, to have the system run auto-
       matically and e-mail you the results of the synchronization.  This user
       interface  is  not  capable  of  reading  a password from the keyboard;
       account passwords must be specified using one of the configuration file
       options.

   NONINTERACTIVE.QUIET
       Noninteractive.Quiet is designed for non-attended running in situations
       where normal status messages are not desired.  It will  output  nothing
       except  errors  and  serious warnings.  Like Noninteractive.Basic, this
       user interface is not capable of reading a password from the  keyboard;
       account passwords must be specified using one of the configuration file
       options.

EXAMPLES
       Here are some example configurations for various situations.  Please e-
       mail any other examples you have that may be useful to me.

   MULTIPLE ACCOUNTS WITH MUTT
       This  example shows you how to set up OfflineIMAP to synchronize multi-
       ple accounts with the mutt mail reader.

       Start by creating a directory to hold your  folders  by  running  mkdir
       ~/Mail.  Then, in your ~/.offlineimaprc, specify:

       accounts = Personal, Work

       Make  sure  that  you  have  both an [Account Personal] and an [Account
       Work] section.  The local repository for each account must have differ-
       ent localfolder path names.  Also, make sure to enable [mbnames].

       In each local repository section, write something like this:

       localfolders = ~/Mail/Personal

       Finally, add these lines to your ~/.muttrc:

       source ~/path-to-mbnames-muttrc-mailboxes
       folder-hook Personal set from="youremail@personal.com"
       folder-hook Work set from="youremail@work.com"
       set mbox_type=Maildir
       set folder=$HOME/Mail
       spoolfile=+Personal/INBOX

       That's it!

   UW-IMAPD AND REFERENCES
       Some users with a UW-IMAPD server need to use OfflineIMAP's "reference"
       feature to get at their mailboxes, specifying a reference  of  "~/Mail"
       or "#mh/" depending on the configuration.  The below configuration from
       (originally from docwhat@gerf.org) shows using a reference of  Mail,  a
       nametrans  that strips the leading Mail/ off incoming folder names, and
       a folderfilter that limits the folders synced to just three.

       [Account Gerf]
       localrepository = GerfLocal
       remoterepository = GerfRemote

       [Repository GerfLocal]
       type = Maildir
       localfolders = ~/Mail

       [Repository GerfRemote]
       type = IMAP
       remotehost = gerf.org
       ssl = yes
       remoteuser = docwhat
       reference = Mail
       # Trims off the preceeding Mail on all the folder names.
       nametrans = lambda foldername: \
                   re.sub('^Mail/', '', foldername)
       # Yeah, you have to mention the Mail dir, even though it
       # would seem intuitive that reference would trim it.
       folderfilter = lambda foldername: foldername in [
             'Mail/INBOX',
             'Mail/list/zaurus-general',
             'Mail/list/zaurus-dev',
             ]
       maxconnections = 1
       holdconnectionopen = no

   PYTHONFILE CONFIGURATION FILE OPTION
       You can have OfflineIMAP load up a Python file  before  evaluating  the
       configuration  file  options that are Python expressions.  This example
       is based on one supplied by Tommi Virtanen for this feature.

       In ~/.offlineimap.rc, he adds these options:

       [general]
       pythonfile=~/.offlineimap.py
       [Repository foo]
       foldersort=mycmp

       Then, the ~/.offlineimap.py file will contain:

       prioritized = ['INBOX', 'personal', 'announce', 'list']

       def mycmp(x, y):
          for prefix in prioritized:
              xsw = x.startswith(prefix)
              ysw = y.startswith(prefix)
              if xsw and ysw:
                 return cmp(x, y)
              elif xsw:
                 return -1
              elif ysw:
                 return +1
          return cmp(x, y)

       def test_mycmp():
          import os, os.path
          folders=os.listdir(os.path.expanduser('~/data/mail/tv@hq.yok.utu.fi'))
          folders.sort(mycmp)
          print folders

       This code snippet illustrates how the foldersort  option  can  be  cus-
       tomized  with  a Python function from the pythonfile to always synchro-
       nize certain folders first.

ERRORS
       If you get one of  some  frequently-encountered  or  confusing  errors,
       please check this section.

   UID VALIDITY PROBLEM FOR FOLDER
       IMAP  servers  use  a  unique  ID (UID) to refer to a specific message.
       This number is guaranteed to be unique to a particular message forever.
       No  other  message in the same folder will ever get the same UID.  UIDs
       are an integral part of OfflineIMAP's synchronization scheme; they  are
       used to match up messages on your computer to messages on the server.

       Sometimes,  the  UIDs on the server might get reset.  Usually this will
       happen if you delete and then recreate a folder.   When  you  create  a
       folder,  the  server  will  often  start  the  UID  back  from  1.  But
       OfflineIMAP might still have the UIDs from the previous folder  by  the
       same  name stored.  OfflineIMAP will detect this condition and skip the
       folder.  This is GOOD, because it prevents data loss.

       You can fix it by removing your  local  folder  and  cache  data.   For
       instance,  if  your folders are under ~/Folders and the folder with the
       problem is INBOX, you'd type this:

       rm -r ~/Folders/INBOX
       rm -r ~/.offlineimap/Account-AccountName
       rm -r ~/.offlineimap/Repository-RepositoryName

       (Of course, replace AccountName and RepositoryName with  the  names  as
       specified in ~/.offlineimaprc).

       Next  time you run OfflineIMAP, it will re-download the folder with the
       new UIDs.  Note that the procedure specified above will lose any  local
       changes made to the folder.

       Some  IMAP servers are broken and do not support UIDs properly.  If you
       continue to get this error for all your folders even  after  performing
       the above procedure, it is likely that your IMAP server falls into this
       category.   OfflineIMAP  is  incompatible  with  such  servers.   Using
       OfflineIMAP  with them will not destroy any mail, but at the same time,
       it will not actually synchronize it either.  (OfflineIMAP  will  detect
       this condition and abort prior to synchronization.)

       This  question  comes  up  frequently  on  the OfflineIMAP mailing list
       <URL:http://lists.complete.org/offlineimap@complete.org/>.    You   can
       find       a       detailed      discussion      <URL:http://lists.com-
       plete.org/offlineimap@complete.org/2003/04/msg00012.html.gz>   of   the
       problem there.

OTHER FREQUENTLY ASKED QUESTIONS
       There  are  some  other FAQs that might not fit into another section of
       the document, so they are discussed here.

       What platforms does OfflineIMAP run on?
              It should run on most platforms supported by Python,  which  are
              quite  a  few.   I  do not support Windows myself, but some have
              made it work there; see the FAQ entry for that platform.

       I'm using Mutt.  Other IMAP  sync  programs  require  me  to  use  "set
       maildir_trash=yes".  Do I need to do that with OfflineIMAP?
              No.  OfflineIMAP is smart enough to figure out message  deletion
              without  this  extra crutch.  You'll get the best results if you
              don't use this setting, in fact.

       I've upgraded and now OfflineIMAP crashes when I start it up!  Why?
              You need to upgrade  your  configuration  file.   See  [XRef  to
              UPGRADING.4.0] at the end of this manual.

       How do I specify the names of my folders?
              You  do  not  need to.  OfflineIMAP is smart enough to automati-
              cally figure out what folders are present on the IMAP server and
              synchronize  them.   You  can use the folderfilter and nametrans
              configuration file options to request certain folders and rename
              them as they come in if you like.

       How can I prevent certain folders from being synced?
              Use the folderfilter option in the configuration file.

       How can I add or delete a folder?
              OfflineIMAP  does not currently provide this feature, but if you
              create a new folder on the  IMAP  server,  it  will  be  created
              locally automatically.

       Are there any other warnings that I should be aware of?
              Yes; see the Notes section below.

       What is the mailbox name recorder (mbnames) for?
              Some  mail  readers,  such as Mutt, are not capable of automati-
              cally determining the names of your mailboxes.  OfflineIMAP  can
              help  these  programs  by  writing the names of the folders in a
              format  you  specify.   See  the  example  offlineimap.conf  for
              details.

       Can I synchronize multiple accounts with OfflineIMAP?
              Sure.   Just  name  them all in the accounts line in the general
              section of the configuration file, and add a per-account section
              for each one.

       Does OfflineIMAP support POP?
              No.  POP is not robust enough to do a completely reliable multi-
              machine synchronization like OfflineIMAP  can  do.   OfflineIMAP
              will not support it.

       Does OfflineIMAP support mailbox formats other than Maildir?
              Not  at  present.   There is no technical reason not to; just no
              demand yet.  Maildir is  a  superior  format  anyway.   However,
              OfflineIMAP  can  sync  between  two IMAP servers, and some IMAP
              servers support other formats.  You could install an IMAP server
              on your local machine and have OfflineIMAP sync to that.

       [technical] Why are your Maildir message filenames so huge?
              OfflineIMAP has two relevant principles: 1) never modifying your
              messages  in   any   way   and   2)   ensuring   100%   reliable
              synchronizations.   In  order to do a reliable sync, OfflineIMAP
              must have a way to uniquely identify each e-mail.  Three  pieces
              of  information  are required to do this: your account name, the
              folder name, and the message UID.  The account name can be  cal-
              culated  from  the  path in which your messages are.  The folder
              name can usually be as well, BUT some mail clients move messages
              between  folders  by  simply  moving  the file, leaving the name
              intact.

              So, OfflineIMAP must store both a UID folder ID.  The folder  ID
              is necessary so OfflineIMAP can detect a message moved to a dif-
              ferent folder.  OfflineIMAP stores the UID (U=  number)  and  an
              md5sum of the foldername (FMD5= number) to facilitate this.

       What is the speed of OfflineIMAP's sync?
              OfflineIMAP  versions 2.0 and above contain a multithreaded sys-
              tem.  A good way to experiment is by setting maxsyncaccounts  to
              3 and maxconnections to 3 in each account clause.

              This  lets  OfflineIMAP  open up multiple connections simultane-
              ously.  That will let it process multiple folders  and  messages
              at  once.   In most cases, this will increase performance of the
              sync.

              Don't set the number too high.  If you  do  that,  things  might
              actually  slow down as your link gets saturated.  Also, too many
              connections can cause  mail  servers  to  have  excessive  load.
              Administrators might take unkindly to this, and the server might
              bog down.  There are many  variables  in  the  optimal  setting;
              experimentation may help.

              An informal benchmark yields these results for my setup:

              o 10 minutes with MacOS X Mail.app "manual cache"

              o 5 minutes with GNUS agent sync

              o 20 seconds with OfflineIMAP 1.x

              o 9 seconds with OfflineIMAP 2.x

              o 3 seconds with OfflineIMAP 3.x "cold start"

              o 2 seconds with OfflineIMAP 3.x "held connection"

       Can I use OfflineIMAP on Windows?
              These answers have been reported by OfflineIMAP users.  I do not
              run OfflineIMAP on Windows myself, so I can't  directly  address
              their accuracy.

              The basic answer is that it's possible and doesn't require hack-
              ing OfflineIMAP source  code.   However,  it's  not  necessarily
              trivial.  The information below is based in instructions submit-
              ted by Chris Walker.

              First,   you   must    run    OfflineIMAP    in    the    Cygwin
              <URL:http://www.cygwin.com/> environment.

              Next,  you'll  need to mount your Maildir directory in a special
              way.  There is information for doing that at
               <URL:http://barnson.org/node/view/295>.  That site  gives  this
              example:

              mount -f -s -b -o managed "d:/tmp/mail" "/home/of/mail"


              That  URL  also has more details on making OfflineIMAP work with
              Windows.

CONFORMING TO
       o Internet Message Access Protocol version 4rev1 (IMAP 4rev1) as speci-
         fied in RFC2060 and RFC3501

       o CRAM-MD5 as specified in RFC2195

       o Maildir      as      specified     in     the     Maildir     manpage
         <URL:http://www.qmail.org/qmail-manual-html/man5/maildir.html>    and
         the qmail website <URL:http://cr.yp.to/proto/maildir.html>.

       o Standard Python 2.2.1 as implemented on POSIX-compliant systems.

NOTES
   DELETING LOCAL FOLDERS
       OfflineIMAP  does  a  two-way  synchronization.  That is, if you make a
       change to the mail on the server, it will be propagated to  your  local
       copy, and vise-versa.  Some people might think that it would be wise to
       just delete all their local mail folders periodically.  If you do  this
       with  OfflineIMAP,  remember  to  also  remove  your local status cache
       (~/.offlineimap by default).  Otherwise, OfflineIMAP will take this  as
       an intentional deletion of many messages and will interpret your action
       as requesting them to be deleted from the  server  as  well.   (If  you
       don't  understand  this, don't worry; you probably won't encounter this
       situation)

   MULTIPLE INSTANCES
       OfflineIMAP is not designed to have several instances (for instance,  a
       cron  job  and  an  interactive  invocation)  run over the same mailbox
       simultaneously.  It will perform  a  check  on  startup  and  abort  if
       another  OfflineIMAP  is already running.  If you need to schedule syn-
       chronizations, please use the autorefresh settings  rather  than  cron.
       Alternatively,  you  can  set  a  separate  metadata directory for each
       instance.

   COPYING MESSAGES BETWEEN FOLDERS
       Normally, when you copy a message between folders or add a new  message
       to  a  folder  locally, OfflineIMAP will just do the right thing.  How-
       ever, sometimes this can be tricky -- if your IMAP server does not pro-
       vide   the  SEARCH  command,  or  does  not  return  something  useful,
       OfflineIMAP cannot determine the new UID of the message.  So, in  these
       rare  instances, OfflineIMAP will upload the message to the IMAP server
       and delete it from your local folder.  Then, on  your  next  sync,  the
       message  will  be re-downloaded with the proper UID.  OfflineIMAP makes
       sure that the message was properly  uploaded  before  deleting  it,  so
       there should be no risk of data loss.

   USE WITH EVOLUTION
       OfflineIMAP  can  work  with Evolution.  To do so, first configure your
       OfflineIMAP account to have sep = / in its configuration.   Then,  con-
       figure  Evolution  with  the  "Maildir-format  mail directories" server
       type.  For the path, you will need to specify the name of the top-level
       folder inside your OfflineIMAP storage location.  You're now set!

   USE WITH KMAIL
       At  this time, I believe that OfflineIMAP with Maildirs is not compati-
       ble with KMail.  KMail cannot work in any mode other than to  move  all
       messages  out of all folders immediately, which (besides being annoying
       and fundamentally broken) is incompatible with OfflineIMAP.

       However, I have made KMail version 3  work  well  with  OfflineIMAP  by
       installing  an IMAP server on my local machine, having OfflineIMAP sync
       to that, and pointing KMail at the same server.

   MAILING LIST
       There is an OfflineIMAP mailing list available.  To subscribe, send the
       text  "Subscribe"  in the subject of a mail to offlineimap-request@com-
       plete.org.  To post,  send  the  message  to  offlineimap@complete.org.
       Archives are available at
        <URL:http://lists.complete.org/offlineimap@complete.org/>.

   BUGS
       Reports  of  bugs  should be sent via e-mail to the OfflineIMAP mailing
       list at offlineimap at complete dot org.  Debian users  are  encouraged
       to instead use the Debian bug-tracking system.

UPGRADING TO 4.0
       If  you  are  upgrading from a version of OfflineIMAP prior to 3.99.12,
       you will find that you will  get  errors  when  OfflineIMAP  starts  up
       (relating  to  ConfigParser or AccountHashGenerator) and the configura-
       tion file.  This is because the config file format  had  to  change  to
       accommodate  new  features  in 4.0.  Fortunately, it's not difficult to
       adjust it to suit.

       First thing you need to do is stop any  running  OfflineIMAP  instance,
       making  sure  first  that it's synced all your mail.  Then, modify your
       ~/.offlineimaprc file.  You'll need to split up  each  account  section
       (make sure that it now starts with "Account ") into two Repository sec-
       tions (one for the local side and another for the  remote  side.)   See
       the  files offlineimap.conf.minimal and offlineimap.conf in the distri-
       bution if you need more assistance.

       OfflineIMAP's status directory area has also changed.   Therefore,  you
       should  delete  everything in ~/.offlineimap as well as your local mail
       folders.

       When you start up OfflineIMAP 4.0, it will re-download  all  your  mail
       from the server and then you can continue using it like normal.

COPYRIGHT
       OfflineIMAP, and this manual, are Copyright  2002, 2003 John Goerzen.

       This program is free software; you can redistribute it and/or modify it
       under the terms of the GNU General Public License as published  by  the
       Free  Software Foundation; either version 2 of the License, or (at your
       option) any later version.

       This program is distributed in the hope that it  will  be  useful,  but
       WITHOUT  ANY  WARRANTY;  without  even  the  implied  warranty  of MER-
       CHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU  General
       Public License for more details.

       You should have received a copy of the GNU General Public License along
       with this program; if not, write to the Free Software Foundation, Inc.,
       59 Temple Place, Suite 330, Boston, MA  02111-1307 USA

       imaplib.py  comes  from  the  Python dev tree and is licensed under the
       GPL-compatible PSF license as stated  in  the  file  COPYRIGHT  in  the
       OfflineIMAP distribution.

AUTHOR
       OfflineIMAP,  its  libraries,  documentation,  and  all included files,
       except where noted, was written by John Goerzen <jgoerzen@complete.org>
       and copyright is held as stated in the COPYRIGHT section.

       OfflineIMAP may be downloaded, and information found, from its homepage
       via either Gopher <URL:gopher://quux.org/1/devel/offlineimap>  or  HTTP
       <URL:http://quux.org/devel/offlineimap>.

       OfflineIMAP may also be downloaded using Subversion.  Additionally, the
       distributed tar.gz may be updated with a simple "svn  update"  command;
       it is ready to go.  For information on getting OfflineIMAP with Subver-
       sion,    please    visit    the    complete.org     Subversion     page
       <URL:http://svn.complete.org/>.

SEE ALSO
       mutt(1), python(1)

HISTORY
       Detailed  history may be found in the file ChangeLog in the OfflineIMAP
       distribution.  Feature and bug histories  may  be  found  in  the  file
       debian/changelog  which,  despite  its  name, is not really Debian-spe-
       cific.  This section provides a large overview.

       Development on OfflineIMAP began on June 18, 2002.  Version  1.0.0  was
       released  three  days later on June 21, 2002.  Point releases followed,
       including speed optimizations and some compatibility fixes.

       Version 2.0.0 was released on July 3, 2002, and represented  the  first
       time  the  synchronization  became multithreaded and, to the best of my
       knowledge, the first multithreaded IMAP  syncrhonizing  application  in
       existance.  The last 2.0.x release, 2.0.8, was made on July 9.

       Version  3.0.0  was  released  on July 11, 2002, and introduced modular
       user interfaces and the first GUI interface for OfflineIMAP.  This man-
       ual  also  was  introduced  with  3.0.0,  along  with many command-line
       options.  Version 3.1.0 was released on July 21, adding the Noninterac-
       tive  user  interfaces, profiling support, and several bugfixes.  3.2.0
       was released on July 24,  adding  support  for  the  Blinkenlights  GUI
       interface.   OfflineIMAP entered maintenance mode for awhile, as it had
       reached a feature-complete milestone in my mind.

       The 3.99.x branch began in on October 7, 2002, to begin work  for  4.0.
       The Curses.Blinkenlights interface was added in 3.99.6, and many archi-
       tectural changes were made.

       4.0.0 was released on July 18, 2003, including the ability to  synchro-
       nize  directly  between  two IMAP servers, the first re-architecting of
       the configuration file to refine the notion of an account, and the  new
       Curses interface.



John Goerzen                     17 June 2005                   OFFLINEIMAP(1)