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fetchmail(1)              fetchmail reference manual              fetchmail(1)



NAME
       fetchmail - fetch mail from a POP, IMAP, ETRN, or ODMR-capable server


SYNOPSIS
       fetchmail [option...] [mailserver...]
       fetchmailconf


DESCRIPTION
       fetchmail  is  a mail-retrieval and forwarding utility; it fetches mail
       from  remote  mailservers  and  forwards  it  to  your  local  (client)
       machine's  delivery  system.   You  can  then handle the retrieved mail
       using normal mail user agents such as mutt(1), elm(1) or Mail(1).   The
       fetchmail utility can be run in a daemon mode to repeatedly poll one or
       more systems at a specified interval.

       The fetchmail program can gather mail from servers  supporting  any  of
       the  common  mail-retrieval protocols: POP2 (legacy, to be removed from
       future release), POP3, IMAP2bis, IMAP4, and IMAP4rev1.  It can also use
       the ESMTP ETRN extension and ODMR.  (The RFCs describing all these pro-
       tocols are listed at the end of this manual page.)

       While fetchmail is primarily intended to be used over on-demand  TCP/IP
       links  (such  as  SLIP  or PPP connections), it may also be useful as a
       message transfer agent for sites which refuse for security  reasons  to
       permit (sender-initiated) SMTP transactions with sendmail.

       If fetchmail is used with a POP or an IMAP server, it has two fundamen-
       tal modes of operation for each user account from  which  it  retrieves
       mail:  singledrop-  and  multidrop-mode.  In singledrop-mode, fetchmail
       assumes that all messages in the user's account are intended for a sin-
       gle  recipient.   An  individual mail message will not be inspected for
       recipient information, rather,  the  identity  of  the  recipient  will
       either default to the local user currently executing fetchmail, or else
       will need to be explicitly specified in the configuration  file.   Sin-
       gledrop-mode  is  used  when  the fetchmailrc configuration contains at
       most a single local user specification for a given server account.

       With multidrop-mode, fetchmail is not able to assume that there is only
       a  single  recipient,  but rather that the mail server account actually
       contains mail intended for any number of different recipients.   There-
       fore,  fetchmail must attempt to deduce the proper "envelope recipient"
       from the mail headers of each message.   In  this  mode  of  operation,
       fetchmail almost resembles an MTA, however it is important to note that
       neither the POP nor IMAP protocols were intended for use in this  fash-
       ion,  and  hence  envelope information is often not directly available.
       Instead, fetchmail must resort to a process of informed  guess-work  in
       an attempt to discover the true envelope recipient of a message, unless
       the ISP stores the envelope information in some header  (not  all  do).
       Even  if this information is present in the headers, the process can be
       error-prone and is dependent upon the specific  mail  server  used  for
       mail  retrieval.   Multidrop-mode is used when more than one local user
       is specified for a particular server account in the configuration file.
       Note  that  the  forgoing discussion of singledrop- and multidrop-modes
       does not apply to the ESMTP ETRN or ODMR retrieval methods, since  they
       are  based upon the SMTP protocol which specifically provides the enve-
       lope recipient to fetchmail.

       As each message is retrieved, fetchmail normally delivers it  via  SMTP
       to  port 25 on the machine it is running on (localhost), just as though
       it were being passed in over a normal TCP/IP link.  fetchmail  provides
       the  SMTP  server  with  an  envelope  recipient  derived in the manner
       described previously.  The mail will then be delivered locally via your
       system's  MDA (Mail Delivery Agent, usually sendmail(8) but your system
       may use a different one such as smail, mmdf, exim, postfix, or  qmail).
       All  the  delivery-control mechanisms (such as .forward files) normally
       available through your system MDA and local delivery agents will there-
       fore work automatically.

       If  no  port 25 listener is available, but your fetchmail configuration
       was told about a reliable local MDA, it will use  that  MDA  for  local
       delivery instead.

       If  the  program fetchmailconf is available, it will assist you in set-
       ting up and editing a fetchmailrc configuration.  It runs under  the  X
       window  system and requires that the language Python and the Tk toolkit
       be present on your system.  If you are first setting up  fetchmail  for
       single-user  mode,  it is recommended that you use Novice mode.  Expert
       mode provides complete control of  fetchmail  configuration,  including
       the  multidrop  features.   In either case, the 'Autoprobe' button will
       tell you the most capable protocol a  given  mailserver  supports,  and
       warn you of potential problems with that server.


GENERAL OPERATION
       The  behavior  of fetchmail is controlled by command-line options and a
       run control file, ~/.fetchmailrc, the syntax of which we describe in  a
       later  section  (this  file  is  what the fetchmailconf program edits).
       Command-line options override ~/.fetchmailrc declarations.

       Each server name that you specify following the options on the  command
       line  will be queried.  If you don't specify any servers on the command
       line, each 'poll' entry in your ~/.fetchmailrc file will be queried.

       To facilitate the use of fetchmail in scripts and pipelines, it returns
       an appropriate exit code upon termination -- see EXIT CODES below.

       The  following  options modify the behavior of fetchmail.  It is seldom
       necessary to specify any of these once you have a working  .fetchmailrc
       file set up.

       Almost  all  options  have a corresponding keyword which can be used to
       declare them in a .fetchmailrc file.

       Some special options are not covered here, but are  documented  instead
       in sections on AUTHENTICATION and DAEMON MODE which follow.

   General Options
       -V | --version
              Displays the version information for your copy of fetchmail.  No
              mail fetch is performed.  Instead, for  each  server  specified,
              all  the  option information that would be computed if fetchmail
              were connecting to that server is displayed.  Any non-printables
              in  passwords  or other string names are shown as backslashed C-
              like escape sequences.  This option is useful for verifying that
              your options are set the way you want them.

       -c | --check
              Return  a status code to indicate whether there is mail waiting,
              without actually fetching  or  deleting  mail  (see  EXIT  CODES
              below).  This option turns off daemon mode (in which it would be
              useless).  It doesn't play well with queries to multiple  sites,
              and doesn't work with ETRN or ODMR.  It will return a false pos-
              itive if you leave read but undeleted mail in your server  mail-
              box  and  your  fetch protocol can't tell kept messages from new
              ones.  This means it will work with IMAP, not  work  with  POP2,
              and may occasionally flake out under POP3.

       -s | --silent
              Silent  mode.   Suppresses all progress/status messages that are
              normally echoed to standard output during a fetch (but does  not
              suppress actual error messages).  The --verbose option overrides
              this.

       -v | --verbose
              Verbose mode.  All control messages passed between fetchmail and
              the  mailserver are echoed to stdout.  Overrides --silent.  Dou-
              bling this option (-v -v) causes extra diagnostic information to
              be printed.

   Disposal Options
       -a | --all | (since v6.3.3) --fetchall
              (Keyword: fetchall, since v3.0) Retrieve both old (seen) and new
              messages from the mailserver.  The default is to fetch only mes-
              sages  the  server has not marked seen.  Under POP3, this option
              also forces the use of RETR rather than  TOP.   Note  that  POP2
              retrieval  behaves  as  though --all is always on (see RETRIEVAL
              FAILURE MODES below) and this option does not work with ETRN  or
              ODMR.   While  the -a and --all command-line and fetchall rcfile
              options have been supported for a long time, the --fetchall com-
              mand-line option was added in v6.3.3.

       -k | --keep
              (Keyword:   keep)   Keep   retrieved   messages  on  the  remote
              mailserver.  Normally, messages are deleted from the  folder  on
              the  mailserver  after they have been retrieved.  Specifying the
              keep option causes retrieved messages to remain in  your  folder
              on the mailserver.  This option does not work with ETRN or ODMR.
              If used with POP3, it is recommended to also specify the  --uidl
              option or uidl keyword.

       -K | --nokeep
              (Keyword:  nokeep)  Delete  retrieved  messages  from the remote
              mailserver.  This option forces retrieved mail  to  be  deleted.
              It may be useful if you have specified a default of keep in your
              .fetchmailrc.  This option is forced on with ETRN and ODMR.

       -F | --flush
              POP3/IMAP only.  This is a dangerous option and can  cause  mail
              loss  when  used improperly. It deletes old (seen) messages from
              the mailserver before retrieving new  messages.   Warning:  This
              can  cause  mail  loss if you check your mail with other clients
              than fetchmail, and cause fetchmail to delete a message  it  had
              never  fetched  before.  It can also cause mail loss if the mail
              server marks the message seen after retrieval  (IMAP2  servers).
              You  should  probably  not use this option in your configuration
              file. If you use it with POP3, you must use the  'uidl'  option.
              What  you  probably  want  is  the default setting: if you don't
              specify '-k', then fetchmail will automatically delete  messages
              after successful delivery.

       --limitflush
              POP3/IMAP  only, since version 6.3.0.  Delete oversized messages
              from the mailserver before retrieving  new  messages.  The  size
              limit  should  be  separately specified with the --limit option.
              This option does not work with ETRN or ODMR.

   Protocol and Query Options
       -p <&lt;proto>&gt; | --proto <&lt;proto>&gt; | --protocol <&lt;proto>&gt;
              (Keyword: proto[col]) Specify the protocol to use when  communi-
              cating with the remote mailserver.  If no protocol is specified,
              the default is AUTO.  proto may be one of the following:

              AUTO   Tries IMAP, POP3, and POP2 (skipping  any  of  these  for
                     which support has not been compiled in).

              POP2   Post Office Protocol 2 (legacy, to be removed from future
                     release)

              POP3   Post Office Protocol 3

              APOP   Use POP3 with old-fashioned MD5-challenge authentication.
                     Considered not resistant to man-in-the-middle attacks.

              RPOP   Use POP3 with RPOP authentication.

              KPOP   Use POP3 with Kerberos V4 authentication on port 1109.

              SDPS   Use POP3 with Demon Internet's SDPS extensions.

              IMAP   IMAP2bis,  IMAP4,  or  IMAP4rev1 (fetchmail automatically
                     detects their capabilities).

              ETRN   Use the ESMTP ETRN option.

              ODMR   Use the the On-Demand Mail Relay ESMTP profile.

       All these alternatives work in basically the  same  way  (communicating
       with standard server daemons to fetch mail already delivered to a mail-
       box on the server) except ETRN and ODMR.  The ETRN mode allows  you  to
       ask  a compliant ESMTP server (such as BSD sendmail at release 8.8.0 or
       higher) to immediately open a sender-SMTP  connection  to  your  client
       machine and begin forwarding any items addressed to your client machine
       in the server's queue of undelivered mail.   The ODMR mode requires  an
       ODMR-capable  server  and  works similarly to ETRN, except that it does
       not require the client machine to have a static DNS.

       -U | --uidl
              (Keyword: uidl) Force  UIDL  use  (effective  only  with  POP3).
              Force client-side tracking of 'newness' of messages (UIDL stands
              for "unique ID listing" and is described in RFC1939).  Use  with
              'keep'  to  use  a  mailbox  as  a baby news drop for a group of
              users. The fact that seen messages are skipped is logged, unless
              error  logging  is  done  through syslog while running in daemon
              mode.  Note that fetchmail may automatically enable this  option
              depending  on upstream server capabilities.  Note also that this
              option may be removed and forced enabled in a  future  fetchmail
              version. See also: --idfile.

       --idle (since 6.3.3)
              (Keyword:  idle,  since before 6.0.0) Enable IDLE use (effective
              only with IMAP). Note that this works with only one folder at  a
              given  time.   While  the idle rcfile keyword had been supported
              for a long time, the --idle command-line  option  was  added  in
              version  6.3.3.  IDLE  use  means  that fetchmail tells the IMAP
              server to send notice of new messages, so they can be  retrieved
              sooner than would be possible with regular polls.

       -P <&lt;portnumber>&gt; | --service <&lt;servicename>&gt;
              (Keyword: service) Since version 6.3.0.  The service option per-
              mits you to specify a service name to connect to.  You can spec-
              ify  a decimal port number here, if your services database lacks
              the required service-port assignments. See the FAQ item R12  and
              the  --ssl  documentation  for  details. This replaces the older
              --port option.

       --port <&lt;portnumber>&gt;
              (Keyword: port) Obsolete version of --service that does not take
              service  names.   Note: this option may be removed from a future
              version.

       --principal <&lt;principal>&gt;
              (Keyword: principal) The principal option permits you to specify
              a service principal for mutual authentication.  This is applica-
              ble to POP3 or IMAP with Kerberos authentication.

       -t <&lt;seconds>&gt; | --timeout <&lt;seconds>&gt;
              (Keyword: timeout) The  timeout  option  allows  you  to  set  a
              server-nonresponse timeout in seconds.  If a mailserver does not
              send a greeting message or respond to  commands  for  the  given
              number of seconds, fetchmail will hang up on it.  Without such a
              timeout fetchmail might hang indefinitely trying to  fetch  mail
              from  a  down  host.   This would be particularly annoying for a
              fetchmail running in the background.  There is a default timeout
              which  fetchmail -V will report.  If a given connection receives
              too many timeouts in  succession,  fetchmail  will  consider  it
              wedged  and stop retrying.  The calling user will be notified by
              email if this happens.

       --plugin <&lt;command>&gt;
              (Keyword: plugin) The plugin option allows you to use an  exter-
              nal  program to establish the TCP connection.  This is useful if
              you want to use SSL, ssh, or need some special firewalling  set-
              up.   The  program will be looked up in $PATH and can optionally
              be passed the hostname and port as arguments using "%h" and "%p"
              respectively (note that the interpolation logic is rather primi-
              tive, and these token must be bounded by whitespace or beginning
              of  string or end of string).  Fetchmail will write to the plug-
              in's stdin and read from the plugin's stdout.

       --plugout <&lt;command>&gt;
              (Keyword: plugout) Identical to the  plugin  option  above,  but
              this  one  is used for the SMTP connections (which will probably
              not need it, so it has been separated from plugin).

       -r <&lt;name>&gt; | --folder <&lt;name>&gt;
              (Keyword: folder[s]) Causes a specified non-default mail  folder
              on  the  mailserver  (or  comma-separated list of folders) to be
              retrieved.  The syntax of the folder name  is  server-dependent.
              This option is not available under POP3, ETRN, or ODMR.

       --tracepolls
              (Keyword:  tracepolls)  Tell fetchmail to poll trace information
              in the form 'polling %s account  %s'  and  'folder  %s'  to  the
              Received  line  it generates, where the %s parts are replaced by
              the user's remote name, the poll label, and the folder (mailbox)
              where  available (the Received header also normally includes the
              server's true name).  This can be used to facilitate  mail  fil-
              tering  based  on  the  account  it  is being received from. The
              folder information is written only since version 6.3.4.

       --ssl  (Keyword: ssl) Causes the connection to the mail  server  to  be
              encrypted  via  SSL.   Connect to the server using the specified
              base protocol over a connection  secured  by  SSL.  This  option
              defeats  TLS  negotiation.  Use --sslcertck to validate the cer-
              tificates presented by the server.

              Note that fetchmail may still try to negotiate TLS even if  this
              option is not given. You can use the --sslproto option to defeat
              this behavior or tell fetchmail to negotiate  a  particular  SSL
              protocol.

              If no port is specified, the connection is attempted to the well
              known port of the SSL version of the  base  protocol.   This  is
              generally a different port than the port used by the base proto-
              col.  For IMAP, this is port 143 for the clear protocol and port
              993  for  the SSL secured protocol, for POP3, it is port 110 for
              the clear text and port 995 for the encrypted variant.

              If your system lacks the corresponding  entries  from  /etc/ser-
              vices,  see  the  --service  option and specify the numeric port
              number as given in the previous paragraph (unless your  ISP  had
              directed you to different ports, which is uncommon however).

       --sslcert <&lt;name>&gt;
              (Keyword:  sslcert)  Specifies  the file name of the client side
              public SSL certificate.  Some SSL encrypted servers may  require
              client  side  keys and certificates for authentication.  In most
              cases, this is optional.  This specifies  the  location  of  the
              public key certificate to be presented to the server at the time
              the SSL session is established.  It is not required (but may  be
              provided)  if  the server does not require it.  Some servers may
              require it, some servers may request it but not require it,  and
              some servers may not request it at all.  It may be the same file
              as the private key (combined key and certificate file) but  this
              is not recommended.

              NOTE: If you use client authentication, the user name is fetched
              from the certificate's CommonName and  overrides  the  name  set
              with --user.

       --sslkey <&lt;name>&gt;
              (Keyword:  sslkey)  Specifies  the  file name of the client side
              private SSL key.  Some SSL encrypted servers may require  client
              side  keys  and certificates for authentication.  In most cases,
              this is optional.  This specifies the location  of  the  private
              key  used  to  sign transactions with the server at the time the
              SSL session is established.  It is not required (but may be pro-
              vided)  if  the  server  does  not require it.  Some servers may
              require it, some servers may request it but not require it,  and
              some servers may not request it at all.  It may be the same file
              as the public key (combined key and certificate file)  but  this
              is  not  recommended.   If  a password is required to unlock the
              key, it will be prompted for at the time just  prior  to  estab-
              lishing  the session to the server.  This can cause some compli-
              cations in daemon mode.

       --sslproto <&lt;name>&gt;
              (Keyword: sslproto) Forces an SSL or TLS protocol. Possible val-
              ues  are  'SSL2',  'SSL3',  'SSL23', and 'TLS1'. Try this if the
              default handshake does not work for your server. Use this option
              with 'TLS1' to enforce a TLS connection. To defeat opportunistic
              TLSv1 negotiation when the server advertises STARTTLS  or  STLS,
              use  ''.  This option, even if the argument is the empty string,
              will also suppress the diagnostic 'SERVER: opportunistic upgrade
              to  TLS.'  message in verbose mode. The default is to try appro-
              priate protocols depending on context.

       --sslcertck
              (Keyword: sslcertck) Causes  fetchmail  to  strictly  check  the
              server  certificate  against a set of local trusted certificates
              (see the sslcertpath option). If the server  certificate  cannot
              be  obtained  or  is  not  signed  by  one  of  the trusted ones
              (directly or indirectly), the SSL connection will fail,  regard-
              less  of the sslfingerprint option.  Note that CRL are only sup-
              ported in OpenSSL 0.9.7 and newer! Your system clock should also
              be reasonably accurate when using this option.

              Note  that this optional behavior may become default behavior in
              future fetchmail versions.

       --sslcertpath <&lt;directory>&gt;
              (Keyword: sslcertpath) Sets the directory fetchmail uses to look
              up  local certificates. The default is your OpenSSL default one.
              The directory must be hashed as OpenSSL expects it - every  time
              you  add  or  modify a certificate in the directory, you need to
              use the c_rehash tool (which comes with OpenSSL  in  the  tools/
              subdirectory).

       --sslcommonname <&lt;common name>&gt;
              (Keyword:  sslcommonname)  Use  of  this  option is discouraged.
              Before using it, contact  the  administrator  of  your  upstream
              server  and ask for a proper SSL certificate to be used. If that
              cannot be attained, this option can be used to specify the  name
              (CommonName)  that  fetchmail expects on the server certificate.
              A correctly configured server will have this set to the hostname
              by  which it is reached, and by default fetchmail will expect as
              much. Use this option when the CommonName is set to  some  other
              value,  to  avoid  the "Server CommonName mismatch" warning, and
              only if the upstream server can't be made to use proper certifi-
              cates.

       --sslfingerprint <&lt;fingerprint>&gt;
              (Keyword:  sslfingerprint) Specify the fingerprint of the server
              key (an MD5 hash of the key) in hexadecimal notation with colons
              separating  groups  of two digits. The letter hex digits must be
              in upper case. This is the default format OpenSSL uses, and  the
              one fetchmail uses to report the fingerprint when an SSL connec-
              tion is established. When this is specified, fetchmail will com-
              pare the server key fingerprint with the given one, and the con-
              nection will fail  if  they  do  not  match  regardless  of  the
              sslcertck  setting.  The  connection will also fail if fetchmail
              cannot obtain an SSL certificate from the server.  This  can  be
              used  to prevent man-in-the-middle attacks, but the finger print
              from the server needs to be obtained or verified over  a  secure
              channel,  and  certainly  not  over the same Internet connection
              that fetchmail would use.

              Using this option will prevent printing certificate verification
              errors as long as --sslcertck is unset.

              To  obtain  the  fingerprint of a certificate stored in the file
              cert.pem, try:

                   openssl x509 -in cert.pem -noout -md5 -fingerprint

              For details, see x509(1ssl).

   Delivery Control Options
       -S <&lt;hosts>&gt; | --smtphost <&lt;hosts>&gt;
              (Keyword: smtp[host]) Specify a hunt list of  hosts  to  forward
              mail  to  (one  or  more  hostnames, comma-separated). Hosts are
              tried in list order; the first one that is up becomes  the  for-
              warding target for the current run.  If this option is not spec-
              ified, 'localhost' is used as the default.   Each  hostname  may
              have  a port number following the host name.  The port number is
              separated from the host name by a slash;  the  default  port  is
              "smtp".   If you specify an absolute path name (beginning with a
              /), it will be interpreted as the name of a UNIX socket  accept-
              ing  LMTP  connections  (such  as is supported by the Cyrus IMAP
              daemon) Example:

                   --smtphost server1,server2/2525,server3,/var/imap/socket/lmtp

              This option can be used with ODMR, and  will  make  fetchmail  a
              relay between the ODMR server and SMTP or LMTP receiver.

       --fetchdomains <&lt;hosts>&gt;
              (Keyword: fetchdomains) In ETRN or ODMR mode, this option speci-
              fies the list of domains the server should ship  mail  for  once
              the connection is turned around.  The default is the FQDN of the
              machine running fetchmail.

       -D <&lt;domain>&gt; | --smtpaddress <&lt;domain>&gt;
              (Keyword: smtpaddress) Specify the  domain  to  be  appended  to
              addresses  in  RCPT  TO  lines shipped to SMTP. When this is not
              specified, the name of the SMTP server (as specified  by  --smt-
              phost)  is  used  for SMTP/LMTP and 'localhost' is used for UNIX
              socket/BSMTP.

       --smtpname <&lt;user@domain>&gt;
              (Keyword: smtpname) Specify the domain and user  to  be  put  in
              RCPT  TO lines shipped to SMTP.  The default user is the current
              local user.

       -Z <&lt;nnn>&gt; | --antispam <&lt;nnn[, nnn]...>&gt;
              (Keyword: antispam) Specifies the list of  numeric  SMTP  errors
              that  are  to  be  interpreted as a spam-block response from the
              listener.  A value of -1 disables this option.  For the command-
              line option, the list values should be comma-separated.

       -m <&lt;command>&gt; | --mda <&lt;command>&gt;
              (Keyword:  mda)  You  can  force  mail  to  be  passed to an MDA
              directly (rather than forwarded to port 25) with the --mda or -m
              option.

              To  avoid losing mail, use this option only with MDAs like mail-
              drop or MTAs like sendmail that return a nonzero status on disk-
              full  and  other  resource-exhaustion errors; the nonzero status
              tells fetchmail that delivery failed and  prevents  the  message
              from being deleted off the server.

              If  fetchmail is running as root, it sets its user id to that of
              the target user while delivering mail through an MDA.  Some pos-
              sible  MDAs  are "/usr/sbin/sendmail -i -f %F -- %T" (Note: some
              several older or vendor sendmail  versions  mistake  --  for  an
              address,  rather than an indicator to mark the end of the option
              arguments), "/usr/bin/deliver" and  "/usr/bin/maildrop  -d  %T".
              Local  delivery  addresses will be inserted into the MDA command
              wherever you place a %T; the mail message's From address will be
              inserted where you place an %F.

              DO  NOT  ENCLOSE THE %F OR %T STRING IN SINGLE QUOTES!  For both
              %T and %F, fetchmail encloses the  addresses  in  single  quotes
              ('),  after  removing any single quotes they may contain, before
              the MDA command is passed to the shell.

              Do NOT use an MDA invocation that dispatches on the contents  of
              To/Cc/Bcc, like "sendmail -i -t" or "qmail-inject", it will cre-
              ate mail loops and bring the just wrath of many postmasters down
              upon  your head.  This is one of the most frequent configuration
              errors!

              Also, do not try to combine multidrop mode with an MDA  such  as
              maildrop  that can only accept one address, unless your upstream
              stores one copy of the message per recipient and transports  the
              envelope recipient in a header; you will lose mail.

              The  well-known  procmail(1)  package  is very hard to configure
              properly, it has a very nasty "fall through to  the  next  rule"
              behavior on delivery errors (even temporary ones, such as out of
              disk space if another user's  mail  daemon  copies  the  mailbox
              around  to  purge old messages), so your mail will end up in the
              wrong mailbox sooner or later. The proper procmail configuration
              is outside the scope of this document. Using maildrop(1) is usu-
              ally much easier, and many users find the filter syntax used  by
              maildrop easier to understand.

              Finally,  we  strongly  advise that you do not use qmail-inject.
              The command line interface  is  non-standard  without  providing
              benefits  for  typical  use,  and fetchmail makes no attempts to
              accomodate qmail-inject's deviations from the standard. Some  of
              qmail-inject's command-line and environment options are actually
              dangerous and can cause broken threads,  non-detected  duplicate
              messages and forwarding loops.


       --lmtp (Keyword:  lmtp)  Cause  delivery  via LMTP (Local Mail Transfer
              Protocol).  A service host and port must be explicitly specified
              on  each  host  in  the  smtphost  hunt list (see above) if this
              option is selected; the default port 25 will (in accordance with
              RFC 2033) not be accepted.

       --bsmtp <&lt;filename>&gt;
              (keyword: bsmtp) Append fetched mail to a BSMTP file.  This sim-
              ply contains the SMTP commands that would normally be  generated
              by  fetchmail  when passing mail to an SMTP listener daemon.  An
              argument of '-' causes the mail to be written to  standard  out-
              put.  Note that fetchmail's reconstruction of MAIL FROM and RCPT
              TO lines is not guaranteed correct; the caveats discussed  under
              THE USE AND ABUSE OF MULTIDROP MAILBOXES below apply.

   Resource Limit Control Options
       -l <&lt;maxbytes>&gt; | --limit <&lt;maxbytes>&gt;
              (Keyword: limit) Takes a maximum octet size argument, where 0 is
              the default and also the special value designating  "no  limit".
              If  nonzero,  messages larger than this size will not be fetched
              and will be left on the  server  (in  foreground  sessions,  the
              progress  messages will note that they are "oversized").  If the
              fetch protocol permits (in particular, under IMAP or POP3  with-
              out the fetchall option) the message will not be marked seen.

              An  explicit  --limit  of 0 overrides any limits set in your run
              control file. This option  is  intended  for  those  needing  to
              strictly  control fetch time due to expensive and variable phone
              rates.

              Combined with --limitflush, it can be used to  delete  oversized
              messages  waiting on a server.  In daemon mode, oversize notifi-
              cations are mailed to  the  calling  user  (see  the  --warnings
              option). This option does not work with ETRN or ODMR.

       -w <&lt;interval>&gt; | --warnings <&lt;interval>&gt;
              (Keyword: warnings) Takes an interval in seconds.  When you call
              fetchmail with a 'limit' option in daemon  mode,  this  controls
              the  interval  at  which  warnings  about oversized messages are
              mailed to the calling user (or the user specified by the  'post-
              master'  option).  One such notification is always mailed at the
              end of  the  the  first  poll  that  the  oversized  message  is
              detected.  Thereafter, re-notification is suppressed until after
              the warning interval elapses (it will take place at the  end  of
              the first following poll).

       -b <&lt;count>&gt; | --batchlimit <&lt;count>&gt;
              (Keyword:  batchlimit)  Specify  the  maximum number of messages
              that will be shipped to an SMTP listener before  the  connection
              is deliberately torn down and rebuilt (defaults to 0, meaning no
              limit).  An explicit --batchlimit of 0 overrides any limits  set
              in  your run control file.  While sendmail(8) normally initiates
              delivery of a message immediately after  receiving  the  message
              terminator,  some  SMTP  listeners are not so prompt.  MTAs like
              smail(8) may wait till the  delivery  socket  is  shut  down  to
              deliver.   This  may  produce  annoying delays when fetchmail is
              processing very large batches.  Setting the batch limit to  some
              nonzero  size  will  prevent these delays.  This option does not
              work with ETRN or ODMR.

       -B <&lt;number>&gt; | --fetchlimit <&lt;number>&gt;
              (Keyword: fetchlimit) Limit the number of messages accepted from
              a  given server in a single poll.  By default there is no limit.
              An explicit --fetchlimit of 0 overrides any limits set  in  your
              run control file.  This option does not work with ETRN or ODMR.

       --fetchsizelimit <&lt;number>&gt;
              (Keyword:  fetchsizelimit) Limit the number of sizes of messages
              accepted from a given server  in  a  single  transaction.   This
              option  is useful in reducing the delay in downloading the first
              mail when there are too many mails in the mailbox.  By  default,
              the  limit is 100.  If set to 0, sizes of all messages are down-
              loaded at the start.  This option does not  work  with  ETRN  or
              ODMR.  For POP3, the only valid non-zero value is 1.

       --fastuidl <&lt;number>&gt;
              (Keyword: fastuidl) Do a binary instead of linear search for the
              first unseen UID. Binary search avoids downloading the  UIDs  of
              all  mails.  This  saves  time (especially in daemon mode) where
              downloading the same set of UIDs in each  poll  is  a  waste  of
              bandwidth.  The  number 'n' indicates how rarely a linear search
              should be done. In daemon mode, linear search is used once  fol-
              lowed  by  binary searches in 'n-1' polls if 'n' is greater than
              1; binary search is always used if 'n' is 1;  linear  search  is
              always  used  if  'n' is 0. In non-daemon mode, binary search is
              used if 'n' is 1; otherwise linear search is used.  The  default
              value of 'n' is 4.  This option works with POP3 only.

       -e <&lt;count>&gt; | --expunge <&lt;count>&gt;
              (keyword:  expunge) Arrange for deletions to be made final after
              a given number of messages.  Under POP2 or POP3, fetchmail  can-
              not  make  deletions  final  without sending QUIT and ending the
              session -- with this option on, fetchmail will break a long mail
              retrieval session into multiple sub-sessions, sending QUIT after
              each sub-session. This is a good defense against line  drops  on
              POP3  servers.  Under IMAP, fetchmail normally issues an EXPUNGE
              command after each deletion in order to force the deletion to be
              done  immediately.   This  is safest when your connection to the
              server is flaky and expensive, as it avoids resending  duplicate
              mail after a line hit.  However, on large mailboxes the overhead
              of re-indexing after every message can slam  the  server  pretty
              hard,  so  if  your  connection  is  reliable  it  is good to do
              expunges less frequently.  Also note that some servers enforce a
              delay  of a few seconds after each quit, so fetchmail may not be
              able to get back in immediately after an expunge -- you may  see
              "lock  busy"  errors if this happens. If you specify this option
              to an integer N, it tells fetchmail to only  issue  expunges  on
              every  Nth  delete.   An  argument  of  zero suppresses expunges
              entirely (so no expunges at all will be done until  the  end  of
              run).  This option does not work with ETRN or ODMR.

   Authentication Options
       -u <&lt;name>&gt; | --user <&lt;name>&gt; | --username <&lt;name>&gt;
              (Keyword:  user[name])  Specifies  the user identification to be
              used when logging in to the mailserver.   The  appropriate  user
              identification  is  both server and user-dependent.  The default
              is your login name on the client machine that is running  fetch-
              mail.  See USER AUTHENTICATION below for a complete description.

       -I <&lt;specification>&gt; | --interface <&lt;specification>&gt;
              (Keyword: interface) Require that a specific interface device be
              up and have a specific local or remote IPv4 (IPv6  is  not  sup-
              ported  by  this  option yet) address (or range) before polling.
              Frequently fetchmail is used  over  a  transient  point-to-point
              TCP/IP  link  established  directly  to a mailserver via SLIP or
              PPP.  That is a  relatively  secure  channel.   But  when  other
              TCP/IP  routes  to  the  mailserver exist (e.g. when the link is
              connected to an alternate ISP), your username and  password  may
              be vulnerable to snooping (especially when daemon mode automati-
              cally polls for mail, shipping a clear password over the net  at
              predictable  intervals).   The --interface option may be used to
              prevent this.  When the specified link is not up or is not  con-
              nected  to  a matching IP address, polling will be skipped.  The
              format is:

                   interface/iii.iii.iii.iii[/mmm.mmm.mmm.mmm]

              The field before the first slash is  the  interface  name  (i.e.
              sl0,  ppp0  etc.).   The  field  before  the second slash is the
              acceptable IP address.  The field after the second  slash  is  a
              mask  which  specifies a range of IP addresses to accept.  If no
              mask is  present  255.255.255.255  is  assumed  (i.e.  an  exact
              match).  This option is currently only supported under Linux and
              FreeBSD. Please see the monitor section for  below  for  FreeBSD
              specific information.

              Note  that  this  option  may be removed from a future fetchmail
              version.

       -M <&lt;interface>&gt; | --monitor <&lt;interface>&gt;
              (Keyword: monitor) Daemon mode can cause transient  links  which
              are  automatically taken down after a period of inactivity (e.g.
              PPP links) to remain up indefinitely.  This option identifies  a
              system  TCP/IP  interface  to  be monitored for activity.  After
              each poll interval, if the link is up but no other activity  has
              occurred  on  the link, then the poll will be skipped.  However,
              when fetchmail is woken up by a signal,  the  monitor  check  is
              skipped  and the poll goes through unconditionally.  This option
              is currently only supported under Linux and  FreeBSD.   For  the
              monitor  and  interface options to work for non root users under
              FreeBSD, the fetchmail binary must be installed SGID kmem.  This
              would  be a security hole, but fetchmail runs with the effective
              GID set to that of the kmem group only when  interface  data  is
              being collected.

              Note  that  this  option  may be removed from a future fetchmail
              version.

       --auth <&lt;type>&gt;
              (Keyword: auth[enticate]) This option permits you to specify  an
              authentication type (see USER AUTHENTICATION below for details).
              The possible values are  any,  password,  kerberos_v5,  kerberos
              (or, for excruciating exactness, kerberos_v4), gssapi, cram-md5,
              otp, ntlm, msn (only for POP3), external (only  IMAP)  and  ssh.
              When any (the default) is specified, fetchmail tries first meth-
              ods that  don't  require  a  password  (EXTERNAL,  GSSAPI,  KER-
              BEROS IV,  KERBEROS 5); then it looks for methods that mask your
              password (CRAM-MD5, X-OTP - note that NTLM and MSN are not auto-
              probed for POP3 and MSN is only supported for POP3); and only if
              the server doesn't support any of those will it ship your  pass-
              word  en  clair.   Other  values  may  be  used to force various
              authentication methods (ssh  suppresses  authentication  and  is
              thus useful for IMAP PREAUTH).  (external suppresses authentica-
              tion and is thus useful for IMAP  EXTERNAL).   Any  value  other
              than password, cram-md5, ntlm, msn or otp suppresses fetchmail's
              normal inquiry for a password.  Specify ssh when you  are  using
              an  end-to-end  secure connection such as an ssh tunnel; specify
              external when you use TLS with client authentication and specify
              gssapi  or  kerberos_v4 if you are using a protocol variant that
              employs GSSAPI or  K4.   Choosing  KPOP  protocol  automatically
              selects Kerberos authentication.  This option does not work with
              ETRN.

   Miscellaneous Options
       -f <&lt;pathname>&gt; | --fetchmailrc <&lt;pathname>&gt;
              Specify a non-default name for the  ~/.fetchmailrc  run  control
              file.   The pathname argument must be either "-" (a single dash,
              meaning to read the configuration  from  standard  input)  or  a
              filename.   Unless the --version option is also on, a named file
              argument  must  have  permissions  no  more   open   than   0600
              (u=rw,g=,o=) or else be /dev/null.

       -i <&lt;pathname>&gt; | --idfile <&lt;pathname>&gt;
              (Keyword:  idfile)  Specify  an alternate name for the .fetchids
              file used to save message UIDs.  NOTE:  since  fetchmail  6.3.0,
              write access to the directory containing the idfile is required,
              as fetchmail writes a temporary file and  renames  it  into  the
              place  of  the  real  idfile only if the temporary file has been
              written successfully. This avoids the truncation of idfiles when
              running out of disk space.

       --pidfile <&lt;pathname>&gt;
              (Keyword:  pidfile; since fetchmail v6.3.4) Override the default
              location of the PID file. Default: see "ENVIRONMENT" below.

       -n | --norewrite
              (Keyword: no rewrite) Normally, fetchmail edits RFC-822  address
              headers  (To,  From,  Cc,  Bcc, and Reply-To) in fetched mail so
              that any mail IDs local to  the  server  are  expanded  to  full
              addresses  (@  and  the mailserver hostname are appended).  This
              enables replies on the client to get addressed correctly (other-
              wise  your  mailer might think they should be addressed to local
              users on the client machine!).  This  option  disables  the  re-
              write.   (This option is provided to pacify people who are para-
              noid about having an MTA edit mail headers and want to know they
              can  prevent it, but it is generally not a good idea to actually
              turn off rewrite.)  When using ETRN or ODMR, the rewrite  option
              is ineffective.

       -E <&lt;line>&gt; | --envelope <&lt;line>&gt;
              (Keyword: envelope; Multidrop only)
              In the configuration file, an enhanced syntax is used:
              envelope [<&lt;count>&gt;] <&lt;line>&gt;

              This  option  changes  the header fetchmail assumes will carry a
              copy of the mail's envelope address.  Normally this is  'X-Enve-
              lope-To'. Other typically found headers to carry envelope infor-
              mation are 'X-Original-To' and 'Delivered-To'.  Now, since these
              headers  are  not standardized, practice varies. See the discus-
              sion of multidrop address handling below.  As  a  special  case,
              'envelope "Received"' enables parsing of sendmail-style Received
              lines.  This is the default, but discouraged because it  is  not
              fully reliable.

              Note  that  fetchmail  expects the Received-line to be in a spe-
              cific format: It must contain "by host for address", where  host
              must match one of the mailserver names that fetchmail recognizes
              for the account in question.

              The optional count argument (only available in the configuration
              file) determines how many header lines of this kind are skipped.
              A count of 1 means: skip the first, take the second. A count  of
              2 means: skip the first and second, take the third, and so on.

       -Q <&lt;prefix>&gt; | --qvirtual <&lt;prefix>&gt;
              (Keyword:  qvirtual;  Multidrop only) The string prefix assigned
              to this option will be removed from the user name found  in  the
              header  specified  with  the  envelope option (before doing mul-
              tidrop name mapping or localdomain checking, if either is appli-
              cable). This option is useful if you are using fetchmail to col-
              lect the mail for an entire domain and your ISP  (or  your  mail
              redirection provider) is using qmail.  One of the basic features
              of qmail is the

              'Delivered-To:'

              message header.  Whenever qmail delivers a message  to  a  local
              mailbox it puts the username and hostname of the envelope recip-
              ient on this line.  The major reason for this is to prevent mail
              loops.   To  set  up qmail to batch mail for a disconnected site
              the ISP-mailhost will have normally put that site in its 'Virtu-
              alhosts'  control  file  so  it  will  add  a prefix to all mail
              addresses for this site. This results in  mail  sent  to  'user-
              nameATuserhost.com'  having a 'Delivered-To:' line of
              the form:

              Delivered-To: mbox-userstr-usernameATuserhost.com

              The ISP can make the 'mbox-userstr-' prefix anything they choose
              but  a  string  matching the user host name is likely.  By using
              the option 'envelope Delivered-To:' you can make fetchmail reli-
              ably  identify  the original envelope recipient, but you have to
              strip the 'mbox-userstr-' prefix to deliver to the correct user.
              This is what this option is for.

       --configdump
              Parse   the  ~/.fetchmailrc  file,  interpret  any  command-line
              options specified, and dump a configuration report  to  standard
              output.  The configuration report is a data structure assignment
              in the language Python.  This option is meant to be used with an
              interactive ~/.fetchmailrc editor like fetchmailconf, written in
              Python.

   Removed Options
       -T | --netsec
              Removed before version 6.3.0, the required underlying inet6_apps
              library had been discontinued and is no longer available.


USER AUTHENTICATION AND ENCRYPTION
       All  modes  except  ETRN  require  authentication  of the client to the
       server.  Normal user authentication in fetchmail is very much like  the
       authentication  mechanism  of ftp(1).  The correct user-id and password
       depend upon the underlying security system at the mailserver.

       If the mailserver is a Unix machine on which you have an ordinary  user
       account,  your regular login name and password are used with fetchmail.
       If you use the same login name  on  both  the  server  and  the  client
       machines,  you  needn't  worry  about  specifying a user-id with the -u
       option -- the default behavior is to use your login name on the  client
       machine  as  the user-id on the server machine.  If you use a different
       login name on the server machine, specify that login name with  the  -u
       option.   e.g. if your login name is 'jsmith' on a machine named 'mail-
       grunt', you would start fetchmail as follows:

              fetchmail -u jsmith mailgrunt

       The default behavior of fetchmail is to prompt you for your  mailserver
       password  before the connection is established.  This is the safest way
       to use fetchmail and ensures that your password  will  not  be  compro-
       mised.  You may also specify your password in your ~/.fetchmailrc file.
       This is convenient when using fetchmail in daemon mode or with scripts.

   Using netrc files
       If you do not specify a password, and fetchmail cannot extract one from
       your ~/.fetchmailrc file, it will look for a ~/.netrc file in your home
       directory before requesting one interactively; if an entry matching the
       mailserver is found in that file, the password will be used.  Fetchmail
       first looks for a match on poll name; if it finds none, it checks for a
       match  on  via name.  See the ftp(1) man page for details of the syntax
       of the ~/.netrc file.  To show a practical example, a .netrc might look
       like this:

              machine hermes.example.org
              login joe
              password topsecret

       You  can  repeat this block with different user information if you need
       to provide more than one password.

       This feature may allow you to avoid duplicating password information in
       more than one file.

       On mailservers that do not provide ordinary user accounts, your user-id
       and password are usually assigned by the server administrator when  you
       apply  for  a mailbox on the server.  Contact your server administrator
       if you don't know the correct user-id and  password  for  your  mailbox
       account.

POP3 VARIANTS
       Early  versions  of  POP3  (RFC1081, RFC1225) supported a crude form of
       independent authentication using the  rhosts  file  on  the  mailserver
       side.   Under  this  RPOP  variant, a fixed per-user ID equivalent to a
       password was sent in clear over a link to a  reserved  port,  with  the
       command  RPOP  rather  than  PASS to alert the server that it should do
       special checking.  RPOP is supported  by  fetchmail  (you  can  specify
       'protocol RPOP' to have the program send 'RPOP' rather than 'PASS') but
       its use is strongly discouraged, and support will  be  removed  from  a
       future fetchmail version.  This facility was vulnerable to spoofing and
       was withdrawn in RFC1460.

       RFC1460 introduced APOP authentication.  In this variant of  POP3,  you
       register  an  APOP  password  on your server host (on some servers, the
       program to do this is called popauth(8)).  You put the same password in
       your ~/.fetchmailrc file.  Each time fetchmail logs in, it sends an MD5
       hash of your password and the server greeting time to the server, which
       can verify it by checking its authorization database.

       Note  that  APOP  is no longer considered resistant against man-in-the-
       middle attacks.

   RETR or TOP
       fetchmail makes some efforts to make the server  believe  messages  had
       not  been  retrieved,  by  using the TOP command with a large number of
       lines when possible.  TOP is a command that retrieves the  full  header
       and  a  fetchmail-specified  amount  of  body lines. It is optional and
       therefore not implemented by all servers, and some are known to  imple-
       ment  it  improperly.  On  many servers however, the RETR command which
       retrieves the full message with header and body, sets the  "seen"  flag
       (for instance, in a web interface), whereas the TOP command does not do
       that.

       fetchmail will always use  the  RETR  command  if  "fetchall"  is  set.
       fetchmail will also use the RETR command if "keep" is set and "uidl" is
       unset.  Finally, fetchmail will use the  RETR  command  on  Maillennium
       POP3/PROXY  servers  (used by Comcast) to avoid a deliberate TOP misin-
       terpretation in this server that causes message corruption.

       In all other cases, fetchmail will use the TOP  command.  This  implies
       that in "keep" setups, "uidl" must be set if "TOP" is desired.

       Note  that  this  description is true for the current version of fetch-
       mail, but the behavior may change in future  versions.  In  particular,
       fetchmail  may  prefer  the RETR command because the TOP command causes
       much grief on some servers and is only optional.

ALTERNATE AUTHENTICATION FORMS
       If your fetchmail was built with Kerberos support and you specify  Ker-
       beros  authentication  (either  with  --auth or the .fetchmailrc option
       authenticate kerberos_v4) it will try to get a Kerberos ticket from the
       mailserver at the start of each query.  Note: if either the pollname or
       via name is 'hesiod', fetchmail will try to use Hesiod to look  up  the
       mailserver.

       If  you  use  POP3  or  IMAP with GSSAPI authentication, fetchmail will
       expect the server to have RFC1731- or RFC1734-conforming  GSSAPI  capa-
       bility, and will use it.  Currently this has only been tested over Ker-
       beros V, so you're expected to already have a  ticket-granting  ticket.
       You  may  pass  a username different from your principal name using the
       standard --user command or by the .fetchmailrc option user.

       If your IMAP daemon returns the PREAUTH response in its greeting  line,
       fetchmail  will  notice  this  and skip the normal authentication step.
       This can be useful, e.g. if you start imapd explicitly using  ssh.   In
       this  case  you can declare the authentication value 'ssh' on that site
       entry to stop .fetchmail from asking you for a password when it  starts
       up.

       If you use client authentication with TLS1 and your IMAP daemon returns
       the AUTH=EXTERNAL response, fetchmail will notice this and will use the
       authentication  shortcut and will not send the passphrase. In this case
       you can declare the authentication value 'external'
        on that site to stop fetchmail from asking you for a password when  it
       starts up.

       If  you are using POP3, and the server issues a one-time-password chal-
       lenge conforming to RFC1938, fetchmail will use your password as a pass
       phrase  to  generate the required response. This avoids sending secrets
       over the net unencrypted.

       Compuserve's RPA authentication is supported. If  you  compile  in  the
       support,  fetchmail  will try to perform an RPA pass-phrase authentica-
       tion instead of sending over the password en clair if it detects "@com-
       puserve.com" in the hostname.

       If  you are using IMAP, Microsoft's NTLM authentication (used by Micro-
       soft Exchange) is supported. If you compile in the  support,  fetchmail
       will try to perform an NTLM authentication (instead of sending over the
       password en clair) whenever the server returns AUTH=NTLM in  its  capa-
       bility   response.   Specify  a  user  option  value  that  looks  like
       'user@domain': the part to the left of the @  will  be  passed  as  the
       username and the part to the right as the NTLM domain.

   Secure Socket Layers (SSL) and Transport Layer Security (TLS)
       You  can  access SSL encrypted services by specifying the --ssl option.
       You can also do this using the "ssl" user option  in  the  .fetchmailrc
       file. With SSL encryption enabled, queries are initiated over a connec-
       tion after negotiating an SSL session, and the connection fails if  SSL
       cannot  be negotiated.  Some services, such as POP3 and IMAP, have dif-
       ferent well known ports defined for the SSL  encrypted  services.   The
       encrypted  ports will be selected automatically when SSL is enabled and
       no explicit port is specified. The --sslproto option  can  be  used  to
       select  the SSL protocols (default: v2 or v3).  The --sslcertck command
       line or sslcertck run control file  option  should  be  used  to  force
       strict certificate checking - see below.

       If  SSL is not configured, fetchmail will usually opportunistically try
       to use TLS. TLS can be enforced by using --sslproto "TLS1". TLS connec-
       tions  use the same port as the unencrypted version of the protocol and
       negotiate TLS via special parameter. The --sslcertck  command  line  or
       sslcertck  run  control file option should be used to force strict cer-
       tificate checking - see below.

       --sslcertck recommended: When connecting to an  SSL  or  TLS  encrypted
       server, the server presents a certificate to the client for validation.
       The certificate is checked to verify that the common name in  the  cer-
       tificate  matches  the  name of the server being contacted and that the
       effective and expiration dates in the certificate indicate that  it  is
       currently  valid.   If  any  of these checks fail, a warning message is
       printed, but the connection continues.  The server certificate does not
       need  to  be  signed  by any specific Certifying Authority and may be a
       "self-signed" certificate. If the --sslcertck command  line  option  or
       sslcertck run control file option is used, fetchmail will instead abort
       if any of these checks fail. Use of the sslcertck or --sslcertck option
       is advised.

       Some  SSL  encrypted  servers may request a client side certificate.  A
       client side public SSL certificate and private SSL key  may  be  speci-
       fied.   If  requested  by the server, the client certificate is sent to
       the server for validation.  Some servers may  require  a  valid  client
       certificate and may refuse connections if a certificate is not provided
       or if the certificate is not valid.  Some servers  may  require  client
       side  certificates be signed by a recognized Certifying Authority.  The
       format for the key files and the certificate files is that required  by
       the underlying SSL libraries (OpenSSL in the general case).

       A  word  of care about the use of SSL: While above mentioned setup with
       self-signed server certificates retrieved over the  wires  can  protect
       you  from  a  passive  eavesdropper,  it doesn't help against an active
       attacker. It's clearly an improvement over  sending  the  passwords  in
       clear, but you should be aware that a man-in-the-middle attack is triv-
       ially possible (in particular with tools such  as  dsniff,  http://mon-
       key.org/~dugsong/dsniff/).   Use  of strict certificate checking with a
       certification authority recognized by server and client, or perhaps  of
       an  SSH  tunnel (see below for some examples) is preferable if you care
       seriously about the security of your mailbox and passwords.

   ESMTP AUTH
       fetchmail also supports authentication  to  the  ESMTP  server  on  the
       client  side  according  to  RFC 2554.  You can specify a name/password
       pair to be used with the keywords 'esmtpname' and 'esmtppassword';  the
       former defaults to the username of the calling user.


DAEMON MODE
   Introducing the daemon mode
       In daemon mode, fetchmail puts itself into the background and runs for-
       ever, querying each specified  host  and  then  sleeping  for  a  given
       polling interval.

   Starting the daemon mode
       There  are  several  ways to make fetchmail work in daemon mode. On the
       command line, --daemon <&lt;interval>&gt; or -d <&lt;interval>&gt; option  runs  fetch-
       mail  in  daemon  mode.  You must specify a numeric argument which is a
       polling interval in seconds.

       Example: simply invoking

              fetchmail -d 900

       will, therefore, poll all the hosts described  in  your  ~/.fetchmailrc
       file (except those explicitly excluded with the 'skip' verb) once every
       15 minutes.

       It is also possible to set a polling interval  in  your  ~/.fetchmailrc
       file  by saying 'set daemon <interval>', where <interval> is an integer
       number of seconds.  If you do this, fetchmail will always start in dae-
       mon mode unless you override it with the command-line option --daemon 0
       or -d0.

       Only one daemon process is permitted per user; in daemon  mode,  fetch-
       mail  sets  up a per-user lockfile to guarantee this.  (You can however
       cheat and set the FETCHMAILHOME environment variable to  overcome  this
       setting,  but  in that case, it is your responsibility to make sure you
       aren't polling the same server with two processes at the same time.)

   Awakening the background daemon
       Normally, calling fetchmail with a daemon in  the  background  sends  a
       wake-up  signal  to the daemon and quits without output. The background
       daemon then starts its next poll cycle immediately.  The  wake-up  sig-
       nal, SIGUSR1, can also be sent manually. The wake-up action also clears
       any 'wedged' flags indicating  that  connections  have  wedged  due  to
       failed authentication or multiple timeouts.

   Terminating the background daemon
       The  option --quit will kill a running daemon process instead of waking
       it up (if there is no such process, fetchmail will notify you.  If  the
       --quit option appears last on the command line, fetchmail will kill the
       running daemon process and then quit. Otherwise, fetchmail  will  first
       kill  a running daemon process and then continue running with the other
       options.

   Useful options for daemon mode
       The -L <&lt;filename>&gt; or --logfile <&lt;filename>&gt; option (keyword: set logfile)
       is  only  effective  when  fetchmail is detached. Note that the logfile
       must exist BEFORE fetchmail is run, you can use  the  touch(1)  command
       with the filename as its sole argument to create it.
       This  option  allows  you  to redirect status messages into a specified
       logfile (follow the option with the  logfile  name).   The  logfile  is
       opened  for  append, so previous messages aren't deleted.  This is pri-
       marily useful for debugging configurations. Note  that  fetchmail  does
       not  detect  if the logfile is rotated, the logfile is only opened once
       when fetchmail starts. You need to restart fetchmail after rotating the
       logfile and before compressing it (if applicable).

       The --syslog option (keyword: set syslog) allows you to redirect status
       and error messages emitted to the syslog(3) system daemon if available.
       Messages are logged with an id of fetchmail, the facility LOG_MAIL, and
       priorities LOG_ERR, LOG_ALERT or LOG_INFO.  This option is intended for
       logging status and error messages which indicate the status of the dae-
       mon and the results while fetching mail from the server(s).  Error mes-
       sages  for  command  line options and parsing the .fetchmailrc file are
       still written to stderr, or to the specified log file.  The  --nosyslog
       option  turns  off  use  of  syslog(3),  assuming it's turned on in the
       ~/.fetchmailrc file, or that the -L  or  --logfile  <&lt;file>&gt;  option  was
       used.

       The  -N or --nodetach option suppresses backgrounding and detachment of
       the daemon process from its  control  terminal.   This  is  useful  for
       debugging  or  when fetchmail runs as the child of a supervisor process
       such as init(8) or Gerrit Pape's runit.  Note that this also causes the
       logfile option to be ignored (though perhaps it shouldn't).

       Note  that  while  running  in  daemon  mode polling a POP2 or IMAP2bis
       server, transient errors (such as DNS  failures  or  sendmail  delivery
       refusals) may force the fetchall option on for the duration of the next
       polling cycle.  This is a robustness feature.  It means that if a  mes-
       sage is fetched (and thus marked seen by the mailserver) but not deliv-
       ered locally due to some transient error, it will be re-fetched  during
       the  next  poll  cycle.   (The IMAP logic doesn't delete messages until
       they're delivered, so this problem does not arise.)

       If you touch or change the ~/.fetchmailrc file while fetchmail is  run-
       ning in daemon mode, this will be detected at the beginning of the next
       poll cycle.  When  a  changed  ~/.fetchmailrc  is  detected,  fetchmail
       rereads  it and restarts from scratch (using exec(2); no state informa-
       tion is retained in the new instance).  Note also that if you break the
       ~/.fetchmailrc file's syntax, the new instance will softly and silently
       vanish away on startup.


ADMINISTRATIVE OPTIONS
       The --postmaster <&lt;name>&gt; option (keyword: set postmaster) specifies  the
       last-resort  username  to which multidrop mail is to be forwarded if no
       matching local recipient can be found. It is also used  as  destination
       of  undeliverable  mail  if  the  'bouncemail' global option is off and
       additionally for spam-blocked mail if the 'bouncemail' global option is
       off  and  the 'spambounce' global option is on. This option defaults to
       the user who invoked fetchmail.  If the invoking user is root, then the
       default of this option is the user 'postmaster'.  Setting postmaster to
       the empty string causes such mail as described above to be discarded  -
       this  however  is  usually a bad idea.  See also the description of the
       'FETCHMAILUSER' environment variable in the ENVIRONMENT section below.

       The --nobounce behaves like the  "set  no  bouncemail"  global  option,
       which see.

       The --invisible option (keyword: set invisible) tries to make fetchmail
       invisible.  Normally, fetchmail behaves like any other MTA would --  it
       generates  a  Received header into each message describing its place in
       the chain of transmission, and tells the MTA it forwards  to  that  the
       mail  came  from  the  machine  fetchmail itself is running on.  If the
       invisible option is on, the Received header is suppressed and fetchmail
       tries  to  spoof  the MTA it forwards to into thinking it came directly
       from the mailserver host.

       The --showdots option (keyword: set showdots) forces fetchmail to  show
       progress  dots  even if the current tty is not stdout (for example log-
       files).  Fetchmail shows the dots by default when run in nodetach  mode
       or when daemon mode is not enabled.

       By  specifying  the  --tracepolls  option, you can ask fetchmail to add
       information to the Received header on the form "polling {label} account
       {user}", where {label} is the account label (from the specified rcfile,
       normally ~/.fetchmailrc) and {user} is the username which  is  used  to
       log  on  to  the mail server. This header can be used to make filtering
       email where no useful header information is available and you want mail
       from  different  accounts  sorted into different mailboxes (this could,
       for example, occur if you have an account on the same server running  a
       mailing  list,  and are subscribed to the list using that account). The
       default is not adding any such header.  In .fetchmailrc, this is called
       'tracepolls'.


RETRIEVAL FAILURE MODES
       The protocols fetchmail uses to talk to mailservers are next to bullet-
       proof.  In normal operation forwarding to port 25, no message  is  ever
       deleted  (or  even marked for deletion) on the host until the SMTP lis-
       tener on the client side has acknowledged to fetchmail that the message
       has been either accepted for delivery or rejected due to a spam block.

       When forwarding to an MDA, however, there is more possibility of error.
       Some MDAs are 'safe' and reliably return a nonzero status on any deliv-
       ery  error, even one due to temporary resource limits.  The maildrop(1)
       program is like this; so are most programs designed as  mail  transport
       agents,  such as sendmail(1), including the sendmail wrapper of Postfix
       and exim(1).  These programs give back a reliable positive acknowledge-
       ment  and  can  be  used with the mda option with no risk of mail loss.
       Unsafe MDAs, though, may return 0 even on delivery  failure.   If  this
       happens, you will lose mail.

       The normal mode of fetchmail is to try to download only 'new' messages,
       leaving untouched  (and  undeleted)  messages  you  have  already  read
       directly  on  the server (or fetched with a previous fetchmail --keep).
       But you may find that messages you've already read on  the  server  are
       being  fetched  (and deleted) even when you don't specify --all.  There
       are several reasons this can happen.

       One could be that you're using POP2.  The  POP2  protocol  includes  no
       representation  of  'new' or 'old' state in messages, so fetchmail must
       treat all messages as new all the time.  But POP2 is obsolete, so  this
       is unlikely.

       A  potential  POP3 problem might be servers that insert messages in the
       middle of mailboxes (some VMS implementations of mail are rumored to do
       this).   The  fetchmail  code assumes that new messages are appended to
       the end of the mailbox; when this is not true it  may  treat  some  old
       messages  as  new and vice versa.  Using UIDL whilst setting fastuidl 0
       might fix this, otherwise, consider switching to IMAP.

       Yet another POP3 problem is that if they can't make  tempfiles  in  the
       user's home directory, some POP3 servers will hand back an undocumented
       response that causes fetchmail to spuriously report "No mail".

       The IMAP code uses the presence or absence of the server flag \Seen  to
       decide  whether or not a message is new.  This isn't the right thing to
       do, fetchmail should check the UIDVALIDITY and use UID, but it  doesn't
       do  that  yet.  Under Unix, it counts on your IMAP server to notice the
       BSD-style Status flags set by mail user agents and set the  \Seen  flag
       from  them when appropriate.  All Unix IMAP servers we know of do this,
       though it's not specified by the IMAP RFCs.  If you ever  trip  over  a
       server that doesn't, the symptom will be that messages you have already
       read on your host will look new to  the  server.   In  this  (unlikely)
       case,  only  messages  you  fetched  with fetchmail --keep will be both
       undeleted and marked old.

       In ETRN and ODMR modes, fetchmail does not actually retrieve  messages;
       instead,  it  asks the server's SMTP listener to start a queue flush to
       the client via SMTP.  Therefore it sends only undelivered messages.


SPAM FILTERING
       Many SMTP listeners allow administrators to set up 'spam filters'  that
       block  unsolicited  email  from specified domains.  A MAIL FROM or DATA
       line that triggers this feature will  elicit  an  SMTP  response  which
       (unfortunately) varies according to the listener.

       Newer versions of sendmail return an error code of 571.

       According  to RFC2821, the correct thing to return in this situation is
       550 "Requested action not taken: mailbox unavailable" (the  draft  adds
       "[E.g.,  mailbox  not  found, no access, or command rejected for policy
       reasons].").

       Older versions of the exim MTA return 501 "Syntax error  in  parameters
       or arguments".

       The postfix MTA runs 554 as an antispam response.

       Zmailer  may  reject  code with a 500 response (followed by an enhanced
       status code that contains more information).

       Return codes which fetchmail treats as antispam responses and  discards
       the  message can be set with the 'antispam' option.  This is one of the
       only three circumstance under which fetchmail ever discards  mail  (the
       others  are the 552 and 553 errors described below, and the suppression
       of multidropped messages with a message-ID already seen).

       If fetchmail is fetching from an IMAP  server,  the  antispam  response
       will be detected and the message rejected immediately after the headers
       have been fetched, without reading the message body.  Thus,  you  won't
       pay for downloading spam message bodies.

       By default, the list of antispam responses is empty.

       If  the spambounce global option is on, mail that is spam-blocked trig-
       gers an RFC1892/RFC1894 bounce message informing the originator that we
       do not accept mail from it. See also BUGS.


SMTP/ESMTP ERROR HANDLING
       Besides  the  spam-blocking  described  above,  fetchmail takes special
       actions on the following SMTP/ESMTP error responses

       452 (insufficient system storage)
            Leave the message in the server mailbox for later retrieval.

       552 (message exceeds fixed maximum message size)
            Delete the message from the server.  Send bounce-mail to the orig-
            inator.

       553 (invalid sending domain)
            Delete  the  message  from  the  server.   Don't  even try to send
            bounce-mail to the originator.

       Other errors trigger bounce mail back to the originator. See also BUGS.


THE RUN CONTROL FILE
       The preferred way to set up fetchmail is to write a  .fetchmailrc  file
       in  your  home directory (you may do this directly, with a text editor,
       or indirectly via fetchmailconf).  When there is a conflict between the
       command-line arguments and the arguments in this file, the command-line
       arguments take precedence.

       To protect the security of your passwords, your ~/.fetchmailrc may  not
       normally  have  more than 0600 (u=rw,g=,o=) permissions; fetchmail will
       complain and exit otherwise (this check is suppressed when --version is
       on).

       You may read the .fetchmailrc file as a list of commands to be executed
       when fetchmail is called with no arguments.

   Run Control Syntax
       Comments begin with a '#' and extend through the end of the line.  Oth-
       erwise the file consists of a series of server entries or global option
       statements in a free-format, token-oriented syntax.

       There are four kinds of tokens: grammar keywords, numbers (i.e. decimal
       digit  sequences),  unquoted  strings,  and  quoted  strings.  A quoted
       string is bounded by double quotes  and  may  contain  whitespace  (and
       quoted  digits are treated as a string).  Note that quoted strings will
       also contain line feed characters if they run across two or more lines,
       unless  you  use  a  backslash  to join lines (see below).  An unquoted
       string is any  whitespace-delimited  token  that  is  neither  numeric,
       string  quoted  nor  contains  the special characters ',', ';', ':', or
       '='.

       Any amount of whitespace separates tokens in  server  entries,  but  is
       otherwise  ignored.  You may use backslash escape sequences (\n for LF,
       \t for HT, \b for BS, \r for CR, \nnn for  decimal  (where  nnn  cannot
       start with a 0), \0ooo for octal, and \xhh for hex) to embed non-print-
       able characters or string delimiters in strings.  In quoted strings,  a
       backslash at the very end of a line will cause the backslash itself and
       the line feed (LF or NL, new line) character to be ignored, so that you
       can  wrap long strings. Without the backslash at the line end, the line
       feed character would become part of the string.

       Warning: while these resemble C-style escape sequences,  they  are  not
       the  same.  fetchmail only supports these eight styles. C supports more
       escape sequences that consist of backslash (\) and a single  character,
       but  does  not support decimal codes and does not require the leading 0
       in octal notation.  Example: fetchmail interprets \233 the same as \xE9
       (Latin  small  letter  e  with  acute), where C would interpret \233 as
       octal 0233 = \x9B (CSI, control sequence introducer).

       Each server entry consists of one of the  keywords  'poll'  or  'skip',
       followed  by a server name, followed by server options, followed by any
       number of user (or username) descriptions, followed  by  user  options.
       Note:  the  most  common  cause  of syntax errors is mixing up user and
       server options or putting user options before the user descriptions.

       For backward compatibility, the word 'server' is a synonym for 'poll'.

       You can use the noise  keywords  'and',  'with',  'has',  'wants',  and
       'options'  anywhere  in  an entry to make it resemble English.  They're
       ignored, but but can make entries much easier to read at a glance.  The
       punctuation characters ':', ';' and ',' are also ignored.

   Poll vs. Skip
       The  'poll' verb tells fetchmail to query this host when it is run with
       no arguments.  The 'skip' verb tells fetchmail not to  poll  this  host
       unless  it  is  explicitly named on the command line.  (The 'skip' verb
       allows you to experiment with test entries safely,  or  easily  disable
       entries for hosts that are temporarily down.)

   Keyword/Option Summary
       Here are the legal options.  Keyword suffixes enclosed in square brack-
       ets are optional.  Those corresponding to  short  command-line  options
       are  followed  by  '-' and the appropriate option letter.  If option is
       only relevant to a single mode of operation, it is noted as 's' or  'm'
       for singledrop- or multidrop-mode, respectively.

       Here are the legal global options:


       l l l lw34.  Keyword   Opt  Mode Function _ set daemon     -d        T{
       Set  a  background  poll  interval  in  seconds.   T}  set   postmaster
                     T{  Give  the  name  of  the  last-resort  mail recipient
       (default: user running fetchmail, "postmaster" if run by the root user)
       T}  set     bouncemail             T{  Direct  error mail to the sender
       (default) T} set no bouncemail             T{ Direct error mail to  the
       local postmaster (as per the 'postmaster' global option above).  T} set
       no  spambounce              T{  Do   not   bounce   spam-blocked   mail
       (default).   T}  set     spambounce             T{ Bounce blocked spam-
       blocked mail (as per the 'antispam' user option) back to  the  destina-
       tion  as  indicated by the 'bouncemail' global option.  Warning: Do not
       use this to bounce spam back to the sender - most  spam  is  sent  with
       false  sender  address  and thus this option hurts innocent bystanders.
       T} set logfile    -L        T{ Name of a file to append error and  sta-
       tus  messages  to.   T} set idfile     -i        T{ Name of the file to
       store UID lists in.  T} set    syslog            T{  Do  error  logging
       through  syslog(3).  T} set no syslog                 T{ Turn off error
       logging   through    syslog(3).    (default)    T}    set    properties
                      T{  String  value  that  is ignored by fetchmail (may be
       used by extension scripts).  T}

       Here are the legal server options:


       l l l lw34.   Keyword    Opt  Mode Function  _  via                  T{
       Specify   DNS   name   of   mailserver,   overriding   poll   name   T}
       proto[col]     -p        T{ Specify protocol (case insensitive):  POP2,
       POP3, IMAP, APOP, KPOP T} local[domains]      m    T{ Specify domain(s)
       to be regarded as local T} port                T{ Specify  TCP/IP  ser-
       vice port (obsolete, use 'service' instead).  T} service   -P        T{
       Specify service name (a numeric value is also allowed and considered  a
       TCP/IP port number).  T} auth[enticate]           T{ Set authentication
       type (default 'any') T} timeout   -t        T{ Server inactivity  time-
       out  in  seconds  (default 300) T} envelope  -E   m    T{ Specify enve-
       lope-address header name T} no envelope         m    T{ Disable looking
       for  envelope  address  T}  qvirtual  -Q   m    T{ Qmail virtual domain
       prefix to remove from  user  name  T}  aka             m    T{  Specify
       alternate  DNS names of mailserver T} interface -I        T{ specify IP
       interface(s) that must be up for server poll to take place  T}  monitor
            -M        T{  Specify IP address to monitor for activity T} plugin
                  T{ Specify command through which to make server connections.
       T}  plugout                   T{  Specify command through which to make
       listener connections.  T} dns            m    T{ Enable DNS lookup  for
       multidrop  (default)  T}  no dns         m    T{ Disable DNS lookup for
       multidrop T} checkalias          m    T{ Do comparison  by  IP  address
       for  multidrop T} no checkalias       m    T{ Do comparison by name for
       multidrop (default) T} uidl      -U        T{ Force POP3 to use client-
       side  UIDLs  (recommended) T} no uidl                  T{ Turn off POP3
       use of client-side UIDLs (default) T} interval                 T{  Only
       check  this site every N poll cycles; N is a numeric argument.  T} tra-
       cepolls               T{ Add poll tracing information to  the  Received
       header T} principal                T{ Set Kerberos principal (only use-
       ful with IMAP and kerberos) T} esmtpname                T{ Set name for
       RFC2554   authentication   to   the   ESMTP   server.    T}  esmtppass-
       word            T{ Set password for RFC2554 authentication to the ESMTP
       server.  T}

       Here are the legal user descriptions and options:


       l l l lw34.  Keyword   Opt  Mode Function _ user[name]     -u        T{
       This is the user description and must come first after server  descrip-
       tion and after possible server options, and before user options.
       It  sets  the  remote user name if by itself or followed by 'there', or
       the local user name if followed by 'here'.  T}  is                   T{
       Connect  local  and remote user names T} to                  T{ Connect
       local and remote  user  names  T}  pass[word]               T{  Specify
       remote  account  password  T}  ssl                 T{ Connect to server
       over the specified  base  protocol  using  SSL  encryption  T}  sslcert
                   T{  Specify  file for client side public SSL certificate T}
       sslkey             T{ Specify file for client side private SSL  key  T}
       sslproto            T{  Force  ssl  protocol  for  connection T} folder
         -r        T{ Specify remote folder to query T} smtphost  -S        T{
       Specify smtp host(s) to forward to T} fetchdomains        m    T{ Spec-
       ify  domains  for   which   mail   should   be   fetched   T}   smtpad-
       dress    -D        T{  Specify the domain to be put in RCPT TO lines T}
       smtpname            T{ Specify the user and domain to be put in RCPT TO
       lines  T}  antispam  -Z        T{  Specify what SMTP returns are inter-
       preted as spam-policy blocks T} mda       -m        T{ Specify MDA  for
       local  delivery  T}  bsmtp     -o        T{ Specify BSMTP batch file to
       append to T} preconnect               T{ Command to be executed  before
       each  connection  T} postconnect              T{ Command to be executed
       after each connection T} keep      -k        T{ Don't delete seen  mes-
       sages   from   server   (for   POP3,  uidl  is  recommended)  T}  flush
         -F        T{ Flush all seen messages before querying  (DANGEROUS)  T}
       limitflush              T{ Flush all oversized messages before querying
       T} fetchall  -a        T{ Fetch all messages whether seen or not T} re-
       write                   T{  Rewrite  destination  addresses  for  reply
       (default) T} stripcr             T{ Strip carriage returns from ends of
       lines T} forcecr             T{ Force carriage returns at ends of lines
       T} pass8bits           T{ Force  BODY=8BITMIME  to  ESMTP  listener  T}
       dropstatus               T{ Strip Status and X-Mozilla-Status lines out
       of incoming  mail  T}  dropdelivered            T{  Strip  Delivered-To
       lines  out  of  incoming  mail  T}  mimedecode               T{ Convert
       quoted-printable to 8-bit in MIME messages  T}  idle                 T{
       Idle  waiting  for  new messages after each poll (IMAP only) T} no keep
        -K        T{  Delete  seen  messages  from  server  (default)  T}   no
       flush            T{  Don't  flush  all  seen  messages  before querying
       (default) T} no fetchall              T{  Retrieve  only  new  messages
       (default)  T}  no  rewrite               T{ Don't rewrite headers T} no
       stripcr               T{ Don't strip carriage returns (default)  T}  no
       forcecr               T{  Don't force carriage returns at EOL (default)
       T} no pass8bits             T{ Don't force BODY=8BITMIME to ESMTP  lis-
       tener  (default) T} no dropstatus            T{ Don't drop Status head-
       ers (default) T} no  dropdelivered              T{  Don't  drop  Deliv-
       ered-To  headers (default) T} no mimedecode            T{ Don't convert
       quoted-printable to  8-bit  in  MIME  messages  (default)  T}  no  idle
                    T{  Don't  idle  waiting  for new messages after each poll
       (IMAP only) T} limit     -l        T{ Set message size limit  T}  warn-
       ings     -w        T{  Set  message  size  warning  interval  T} batch-
       limit     -b        T{ Max # messages to forward in single  connect  T}
       fetchlimit     -B        T{  Max  # messages to fetch in single connect
       T} fetchsizelimit           T{ Max # message sizes to fetch  in  single
       transaction  T}  fastuidl            T{  Use  binary  search  for first
       unseen message (POP3 only) T} expunge   -e        T{ Perform an expunge
       on   every   #th   message   (IMAP   and   POP3   only)  T}  properties
                    T{ String value is ignored by fetchmail (may  be  used  by
       extension scripts) T}

       All  user  options must begin with a user description (user or username
       option) and follow all server descriptions and options.

       In the .fetchmailrc file, the 'envelope' string argument  may  be  pre-
       ceded  by a whitespace-separated number.  This number, if specified, is
       the number of such headers to skip over (that  is,  an  argument  of  1
       selects  the second header of the given type).  This is sometime useful
       for ignoring bogus envelope headers created by an ISP's local  delivery
       agent  or  internal  forwards  (through  mail  inspection  systems, for
       instance).

   Keywords Not Corresponding To Option Switches
       The 'folder' and 'smtphost' options (unlike their command-line  equiva-
       lents)  can  take  a  space- or comma-separated list of names following
       them.

       All options correspond to the obvious  command-line  arguments,  except
       the  following:  'via',  'interval', 'aka', 'is', 'to', 'dns'/'no dns',
       'checkalias'/'no checkalias', 'password', 'preconnect',  'postconnect',
       'localdomains',   'stripcr'/'no   stripcr',   'forcecr'/'no   forcecr',
       'pass8bits'/'no  pass8bits'  'dropstatus/no  dropstatus',   'dropdeliv-
       ered/no  dropdelivered', 'mimedecode/no mimedecode', 'no idle', and 'no
       envelope'.

       The 'via' option is for if you want to have more than one configuration
       pointing  at the same site.  If it is present, the string argument will
       be taken as the actual DNS name of the mailserver host to query.   This
       will override the argument of poll, which can then simply be a distinct
       label for the configuration (e.g. what you would give  on  the  command
       line to explicitly query this host).

       The  'interval'  option  (which takes a numeric argument) allows you to
       poll a server less frequently than the basic poll interval.  If you say
       'interval N' the server this option is attached to will only be queried
       every N poll intervals.

   Singledrop vs. Multidrop options
       Please ensure you read the section titled THE USE  AND  ABUSE  OF  MUL-
       TIDROP MAILBOXES if you intend to use multidrop mode.

       The  'is'  or  'to'  keywords  associate  the  following local (client)
       name(s) (or server-name to client-name mappings separated  by  =)  with
       the mailserver user name in the entry.  If an is/to list has '*' as its
       last name, unrecognized names are  simply  passed  through.  Note  that
       until  fetchmail version 6.3.4 inclusively, these lists could only con-
       tain local parts of user names (fetchmail would only look at  the  part
       before  the  @  sign).  fetchmail versions 6.3.5 and newer support full
       addresses on the left hand side of these mappings, and they take prece-
       dence over any 'localdomains', 'aka', 'via' or similar mappings.

       A  single  local name can be used to support redirecting your mail when
       your username on the client machine is different from your name on  the
       mailserver.   When there is only a single local name, mail is forwarded
       to that local username regardless of the message's  Received,  To,  Cc,
       and Bcc headers.  In this case, fetchmail never does DNS lookups.

       When  there  is  more  than one local name (or name mapping), fetchmail
       looks at the envelope header,  if  configured,  and  otherwise  at  the
       Received, To, Cc, and Bcc headers of retrieved mail (this is 'multidrop
       mode').  It looks for addresses with hostname  parts  that  match  your
       poll  name  or your 'via', 'aka' or 'localdomains' options, and usually
       also for  hostname  parts  which  DNS  tells  it  are  aliases  of  the
       mailserver.  See the discussion of 'dns', 'checkalias', 'localdomains',
       and 'aka' for details on how matching addresses are handled.

       If fetchmail cannot  match  any  mailserver  usernames  or  localdomain
       addresses,  the  mail  will be bounced.  Normally it will be bounced to
       the sender, but if the 'bouncemail' global option is off, the mail will
       go  to  the  local  postmaster  instead.   (see the 'postmaster' global
       option). See also BUGS.

       The 'dns' option (normally on) controls the  way  addresses  from  mul-
       tidrop  mailboxes are checked.  On, it enables logic to check each host
       address that does not match an 'aka' or 'localdomains'  declaration  by
       looking  it  up  with  DNS.   When  a mailserver username is recognized
       attached to a matching hostname part, its local mapping is added to the
       list of local recipients.

       The 'checkalias' option (normally off) extends the lookups performed by
       the 'dns' keyword in multidrop mode,  providing  a  way  to  cope  with
       remote  MTAs that identify themselves using their canonical name, while
       they're polled using an alias.  When such a server is polled, checks to
       extract  the  envelope  address fail, and fetchmail reverts to delivery
       using  the  To/Cc/Bcc  headers  (See   below   'Header   vs.   Envelope
       addresses').   Specifying  this  option instructs fetchmail to retrieve
       all the IP addresses associated with both the poll name  and  the  name
       used  by  the  remote  MTA  and to do a comparison of the IP addresses.
       This comes in handy in situations where  the  remote  server  undergoes
       frequent canonical name changes, that would otherwise require modifica-
       tions to the rcfile.  'checkalias' has no effect if 'no dns' is  speci-
       fied in the rcfile.

       The 'aka' option is for use with multidrop mailboxes.  It allows you to
       pre-declare a list of DNS aliases for a server.  This is  an  optimiza-
       tion  hack  that  allows you to trade space for speed.  When fetchmail,
       while processing a multidrop mailbox, grovels through  message  headers
       looking for names of the mailserver, pre-declaring common ones can save
       it from having to do DNS lookups.  Note: the names you  give  as  argu-
       ments  to  'aka'  are  matched as suffixes -- if you specify (say) 'aka
       netaxs.com', this will match not just a hostname  netaxs.com,  but  any
       hostname  that  ends  with '.netaxs.com'; such as (say) pop3.netaxs.com
       and mail.netaxs.com.

       The 'localdomains' option allows you to declare a list of domains which
       fetchmail  should  consider  local.   When fetchmail is parsing address
       lines in multidrop modes, and a trailing segment of a host name matches
       a declared local domain, that address is passed through to the listener
       or MDA unaltered (local-name mappings are not applied).

       If you are using 'localdomains', you may also need to specify 'no enve-
       lope',  which disables fetchmail's normal attempt to deduce an envelope
       address from the Received line  or  X-Envelope-To  header  or  whatever
       header has been previously set by 'envelope'.  If you set 'no envelope'
       in the defaults entry it is possible to undo that in individual entries
       by using 'envelope <string>'.  As a special case, 'envelope "Received"'
       restores the default parsing of Received lines.

       The password option requires a string argument, which is  the  password
       to be used with the entry's server.

       The  'preconnect'  keyword  allows you to specify a shell command to be
       executed just before each time fetchmail establishes a mailserver  con-
       nection.  This may be useful if you are attempting to set up secure POP
       connections with the aid of ssh(1).  If the command returns  a  nonzero
       status, the poll of that mailserver will be aborted.

       Similarly,  the 'postconnect' keyword similarly allows you to specify a
       shell command to be executed just after each time a mailserver  connec-
       tion is taken down.

       The  'forcecr'  option controls whether lines terminated by LF only are
       given CRLF termination before  forwarding.   Strictly  speaking  RFC821
       requires  this,  but few MTAs enforce the requirement it so this option
       is normally off (only one such MTA, qmail, is  in  significant  use  at
       time of writing).

       The 'stripcr' option controls whether carriage returns are stripped out
       of retrieved mail before it is forwarded.  It is normally not necessary
       to  set  this,  because it defaults to 'on' (CR stripping enabled) when
       there is an MDA declared but 'off' (CR stripping  disabled)  when  for-
       warding is via SMTP.  If 'stripcr' and 'forcecr' are both on, 'stripcr'
       will override.

       The 'pass8bits' option exists to cope with Microsoft mail programs that
       stupidly  slap a "Content-Transfer-Encoding: 7bit" on everything.  With
       this option off (the default) and  such  a  header  present,  fetchmail
       declares  BODY=7BIT  to an ESMTP-capable listener; this causes problems
       for messages actually using 8-bit ISO or KOI-8  character  sets,  which
       will be garbled by having the high bits of all characters stripped.  If
       'pass8bits' is on, fetchmail is forced to declare BODY=8BITMIME to  any
       ESMTP-capable  listener.   If  the  listener is 8-bit-clean (as all the
       major ones now are) the right thing will probably result.

       The 'dropstatus' option controls whether nonempty Status and X-Mozilla-
       Status  lines  are retained in fetched mail (the default) or discarded.
       Retaining them allows your MUA to  see  what  messages  (if  any)  were
       marked seen on the server.  On the other hand, it can confuse some new-
       mail notifiers, which assume that anything with a Status line in it has
       been  seen.   (Note:  the empty Status lines inserted by some buggy POP
       servers are unconditionally discarded.)

       The 'dropdelivered' option controls whether Delivered-To  headers  will
       be  kept  in fetched mail (the default) or discarded. These headers are
       added by Qmail and Postfix mailservers in order to avoid mail loops but
       may get in your way if you try to "mirror" a mailserver within the same
       domain. Use with caution.

       The 'mimedecode'  option  controls  whether  MIME  messages  using  the
       quoted-printable  encoding  are automatically converted into pure 8-bit
       data. If you are delivering mail to an ESMTP-capable, 8-bit-clean  lis-
       tener  (that  includes  all of the major MTAs like sendmail), then this
       will automatically convert quoted-printable message  headers  and  data
       into  8-bit  data, making it easier to understand when reading mail. If
       your e-mail programs know how to deal with  MIME  messages,  then  this
       option is not needed.  The mimedecode option is off by default, because
       doing RFC2047 conversion on headers throws away character-set  informa-
       tion and can lead to bad results if the encoding of the headers differs
       from the body encoding.

       The 'idle' option is intended to be used with IMAP  servers  supporting
       the  RFC2177  IDLE command extension, but does not strictly require it.
       If it is enabled, and fetchmail detects that IDLE is supported, an IDLE
       will be issued at the end of each poll.  This will tell the IMAP server
       to hold the connection open and notify the  client  when  new  mail  is
       available.   If  IDLE  is  not supported, fetchmail will simulate it by
       periodically issuing NOOP. If you need to poll a link frequently,  IDLE
       can  save  bandwidth  by  eliminating  TCP/IP connects and LOGIN/LOGOUT
       sequences. On the other hand, an IDLE connection will eat almost all of
       your  fetchmail's  time,  because it will never drop the connection and
       allow other polls to occur unless the server times out  the  IDLE.   It
       also  doesn't  work  with  multiple folders; only the first folder will
       ever be polled.


       The 'properties' option is an extension mechanism.  It takes  a  string
       argument,  which  is  ignored by fetchmail itself.  The string argument
       may be used  to  store  configuration  information  for  scripts  which
       require  it.   In  particular, the output of '--configdump' option will
       make properties associated with a user entry  readily  available  to  a
       Python script.

   Miscellaneous Run Control Options
       The  words  'here'  and  'there' have useful English-like significance.
       Normally 'user eric is esr' would mean that mail for  the  remote  user
       'eric'  is  to  be delivered to 'esr', but you can make this clearer by
       saying 'user eric there is esr here', or reverse it by saying 'user esr
       here is eric there'

       Legal protocol identifiers for use with the 'protocol' keyword are:

           auto (or AUTO) (legacy, to be removed from future release)
           pop2 (or POP2) (legacy, to be removed from future release)
           pop3 (or POP3)
           sdps (or SDPS)
           imap (or IMAP)
           apop (or APOP)
           kpop (or KPOP)


       Legal  authentication  types  are  'any', 'password', 'kerberos', 'ker-
       beros_v4', 'kerberos_v5' and 'gssapi', 'cram-md5', 'otp',  'msn'  (only
       for  POP3), 'ntlm', 'ssh', 'external' (only IMAP).  The 'password' type
       specifies authentication by normal  transmission  of  a  password  (the
       password  may  be plain text or subject to protocol-specific encryption
       as in CRAM-MD5); 'kerberos' tells fetchmail to try to  get  a  Kerberos
       ticket at the start of each query instead, and send an arbitrary string
       as the password; and 'gssapi' tells fetchmail to use GSSAPI authentica-
       tion.  See the description of the 'auth' keyword for more.

       Specifying  'kpop'  sets  POP3 protocol over port 1109 with Kerberos V4
       authentication.  These defaults may be overridden by later options.

       There are some global option statements: 'set logfile'  followed  by  a
       string  sets  the  same  global specified by --logfile.  A command-line
       --logfile option will override this. Note that --logfile is only effec-
       tive  if  fetchmail  detaches  itself from the terminal and the logfile
       already exists before fetchmail is run.  Also, 'set  daemon'  sets  the
       poll  interval  as --daemon does.  This can be overridden by a command-
       line --daemon option; in particular --daemon 0 can  be  used  to  force
       foreground  operation.  The 'set postmaster' statement sets the address
       to which multidrop  mail  defaults  if  there  are  no  local  matches.
       Finally, 'set syslog' sends log messages to syslogd(8).


DEBUGGING FETCHMAIL
   Fetchmail crashing
       There are various ways in that fetchmail may "crash", i. e. stop opera-
       tion suddenly and unexpectedly. A "crash" usually refers  to  an  error
       condition  that  the  software  did  not handle by itself. A well-known
       failure mode is the "segmentation fault" or "signal 11" or "SIGSEGV" or
       just  "segfault" for short. These can be caused by hardware or by soft-
       ware problems. Software-induced segfaults  can  usually  be  reproduced
       easily and in the same place, whereas hardware-induced segfaults can go
       away if the computer is rebooted, or powered off for a few  hours,  and
       can  happen  in  random locations even if you use the software the same
       way.

       For solving hardware-induced segfaults, find the faulty  component  and
       repair  or  replace  it.  <http://www.bitwizard.nl/sig11/>; may help you
       with details.

       For solving software-induced  segfaults,  the  developers  may  need  a
       "stack backtrace".


   Enabling fetchmail core dumps
       By  default,  fetchmail  suppresses  core  dumps as these might contain
       passwords and other  sensitive  information.  For  debugging  fetchmail
       crashes,  obtaining  a  "stack backtrace" from a core dump is often the
       quickest way to solve the problem, and when posting your problem  on  a
       mailing list, the developers may ask you for a "backtrace".

       1.  To  get  useful backtraces, fetchmail needs to be installed without
       getting stripped  of  its  compilation  symbols.   Unfortunately,  most
       binary  packages  that  are installed are stripped, and core files from
       symbol-stripped programs are worthless. So you may  need  to  recompile
       fetchmail. On many systems, you can type

               file `which fetchmail`

       to  find  out  if  fetchmail  was  symbol-stripped or not. If yours was
       unstripped, fine, proceed, if it was stripped, you  need  to  recompile
       the  source code first. You do not usually need to install fetchmail in
       order to debug it.

       2. The shell environment that starts fetchmail  needs  to  enable  core
       dumps.  The  key  is the "maximum core (file) size" that can usually be
       configured with a tool named "limit" or "ulimit". See the documentation
       for  your  shell  for  details.  In the popular bash shell, "ulimit -Sc
       unlimited" will allow the core dump.

       3. You need to tell fetchmail, too, to allow core dumps.  To  do  this,
       run  fetchmail with the -d0 -v options.  It is often easier to also add
       --nosyslog -N as well.

       Finally, you need to reproduce the crash. You can just start  fetchmail
       from  the directory where you compiled it by typing ./fetchmail, so the
       complete command line will start with ./fetchmail -Nvd0 --nosyslog  and
       perhaps list your other options.

       After the crash, run your debugger to obtain the core dump.  The debug-
       ger will often be GNU GDB, you can then type (adjust  paths  as  neces-
       sary) gdb ./fetchmail fetchmail.core and then, after GDB has started up
       and read all its files, type backtrace full, save the  output  (copy  &
       paste  will  do,  the  backtrace will be read by a human) and then type
       quit to leave gdb.  Note: on some systems, the core files have  differ-
       ent  names, they might contain a number instead of the program name, or
       number and name, but it will usually have "core" as part of their name.


INTERACTION WITH RFC 822
       When trying to determine the originating address of a  message,  fetch-
       mail looks through headers in the following order:

               Return-Path:
               Resent-Sender: (ignored if it doesn't contain an @ or !)
               Sender: (ignored if it doesn't contain an @ or !)
               Resent-From:
               From:
               Reply-To:
               Apparently-From:

       The  originating  address is used for logging, and to set the MAIL FROM
       address when forwarding to SMTP.  This order is intended to cope grace-
       fully  with  receiving  mailing  list  messages  in multidrop mode. The
       intent is that if a local address doesn't  exist,  the  bounce  message
       won't  be  returned  blindly  to  the author or to the list itself, but
       rather to the list manager (which is less annoying).

       In multidrop mode, destination headers are processed as follows: First,
       fetchmail  looks  for  the header specified by the 'envelope' option in
       order to  determine  the  local  recipient  address.  If  the  mail  is
       addressed  to  more than one recipient, the Received line won't contain
       any information regarding recipient addresses.

       Then fetchmail looks for the Resent-To:,  Resent-Cc:,  and  Resent-Bcc:
       lines.   If  they  exist,  they should contain the final recipients and
       have precedence over their To:/Cc:/Bcc: counterparts.  If the  Resent-*
       lines  don't  exist,  the  To:,  Cc:, Bcc: and Apparently-To: lines are
       looked for. (The presence of a Resent-To: is taken to  imply  that  the
       person  referred  by  the To: address has already received the original
       copy of the mail.)


CONFIGURATION EXAMPLES
       Note that although there are password declarations in a  good  many  of
       the  examples below, this is mainly for illustrative purposes.  We rec-
       ommend stashing account/password pairs in your $HOME/.netrc file, where
       they  can  be  used  not just by fetchmail but by ftp(1) and other pro-
       grams.

       Basic format is:

         poll SERVERNAME protocol PROTOCOL username NAME password PASSWORD

       Example:

         poll pop.provider.net protocol pop3 username "jsmith" password "secret1" ssl

       Or, using some abbreviations:

         poll pop.provider.net proto pop3 user "jsmith" password "secret1"

       Multiple servers may be listed:

         poll pop.provider.net proto pop3 user "jsmith" pass "secret1"
         poll other.provider.net proto pop2 user "John.Smith" pass "My^Hat"

       Here's a version of those two  with  more  whitespace  and  some  noise
       words:

         poll pop.provider.net proto pop3
             user "jsmith", with password secret1, is "jsmith" here;
         poll other.provider.net proto pop2:
             user "John.Smith", with password "My^Hat", is "John.Smith" here;

       This version is much easier to read and doesn't cost significantly more
       (parsing is done only once, at startup time).


       If you need to include whitespace in a parameter string  or  start  the
       latter with a number, enclose the string in double quotes.  Thus:

         poll mail.provider.net with proto pop3:
               user "jsmith" there has password "4u but u can't krak this"
                           is jws here and wants mda "/bin/mail"

       You  may  have  an  initial  server  description  headed by the keyword
       'defaults' instead of 'poll' followed by a  name.   Such  a  record  is
       interpreted  as  defaults for all queries to use. It may be overwritten
       by individual server descriptions.  So, you could write:

         defaults proto pop3
               user "jsmith"
         poll pop.provider.net
               pass "secret1"
         poll mail.provider.net
               user "jjsmith" there has password "secret2"

       It's possible to specify more than one user  per  server.   The  'user'
       keyword leads off a user description, and every user specification in a
       multi-user entry must include it.  Here's an example:

         poll pop.provider.net proto pop3 port 3111
               user "jsmith" with pass "secret1" is "smith" here
               user jones with pass "secret2" is "jjones" here keep

       This associates the local username 'smith'  with  the  pop.provider.net
       username   'jsmith'   and   the   local   username  'jjones'  with  the
       pop.provider.net username 'jones'.  Mail for 'jones'  is  kept  on  the
       server after download.

       Here's  what  a  simple retrieval configuration for a multidrop mailbox
       looks like:

         poll pop.provider.net:
               user maildrop with pass secret1 to golux 'hurkle'='happy' snark here

       This says that the mailbox of account 'maildrop' on  the  server  is  a
       multidrop  box, and that messages in it should be parsed for the server
       user names 'golux', 'hurkle', and 'snark'.  It further  specifies  that
       'golux'  and 'snark' have the same name on the client as on the server,
       but mail for server user 'hurkle' should be delivered  to  client  user
       'happy'.

       Note   that   fetchmail,  until  version  6.3.4,  did  NOT  allow  full
       user@domain specifications here, these  would  never  match.  Fetchmail
       6.3.5  and  newer  support  user@domain specifications on the left-hand
       side of a user mapping.

       Here's an example of another kind of multidrop connection:

         poll pop.provider.net localdomains loonytoons.org toons.org
             envelope X-Envelope-To
               user maildrop with pass secret1 to * here

       This also says that the mailbox of account 'maildrop' on the server  is
       a  multidrop  box.   It  tells fetchmail that any address in the loony-
       toons.org or toons.org domains  (including  sub-domain  addresses  like
       'joeATdaffy.org')  should be passed through to the local SMTP
       listener without modification.  Be careful of  mail  loops  if  you  do
       this!

       Here's  an  example configuration using ssh and the plugin option.  The
       queries are made directly on the stdin and stdout  of  imapd  via  ssh.
       Note that in this setup, IMAP authentication can be skipped.

       poll mailhost.net with proto imap:
               plugin "ssh %h /usr/sbin/imapd" auth ssh;
            user esr is esr here


THE USE AND ABUSE OF MULTIDROP MAILBOXES
       Use  the multiple-local-recipients feature with caution -- it can bite.
       All multidrop features are ineffective in ETRN and ODMR modes.

       Also, note that in multidrop mode duplicate mails  are  suppressed.   A
       piece  of mail is considered duplicate if it has the same message-ID as
       the message immediately preceding and more than  one  addressee.   Such
       runs of messages may be generated when copies of a message addressed to
       multiple users are delivered to a multidrop box.


   Header vs. Envelope addresses
       The fundamental problem is that by having your mailserver toss  several
       peoples' mail in a single maildrop box, you may have thrown away poten-
       tially vital information about who each  piece  of  mail  was  actually
       addressed  to  (the  'envelope  address',  as  opposed  to  the  header
       addresses in the RFC822 To/Cc headers - the Bcc is not available at the
       receiving  end).   This  'envelope  address' is the address you need in
       order to reroute mail properly.

       Sometimes fetchmail can deduce the envelope address.  If the mailserver
       MTA  is  sendmail  and the item of mail had just one recipient, the MTA
       will have written a 'by/for' clause that gives the  envelope  addressee
       into  its  Received  header.  But  this doesn't work reliably for other
       MTAs, nor if there is more than one recipient.  By  default,  fetchmail
       looks  for  envelope  addresses  in  these  lines; you can restore this
       default with -E "Received" or 'envelope Received'.

       As a better alternative, some SMTP listeners and/or mail servers insert
       a  header  in each message containing a copy of the envelope addresses.
       This header (when it exists) is often  'X-Original-To',  'Delivered-To'
       or  'X-Envelope-To'.   Fetchmail's assumption about this can be changed
       with the -E or 'envelope' option.  Note that writing an envelope header
       of  this  kind  exposes  the  names of recipients (including blind-copy
       recipients) to all receivers of the  messages,  so  the  upstream  must
       store one copy of the message per recipient to avoid becoming a privacy
       problem.

       Postfix, since version 2.0, writes an X-Original-To: header which  con-
       tains a copy of the envelope as it was received.

       Qmail and Postfix generally write a 'Delivered-To' header upon deliver-
       ing the message to the mail spool and  use  it  to  avoid  mail  loops.
       Qmail  virtual  domains however will prefix the user name with a string
       that normally matches the user's domain. To remove this prefix you  can
       use the -Q or 'qvirtual' option.

       Sometimes,  unfortunately, neither of these methods works.  That is the
       point when you should contact your ISP and ask them to provide such  an
       envelope  header,  and  you should not use multidrop in this situation.
       When they all fail, fetchmail must fall back on the contents  of  To/Cc
       headers (Bcc headers are not available - see below) to try to determine
       recipient addressees -- and these are unreliable.  In particular, mail-
       ing-list software often ships mail with only the list broadcast address
       in the To header.

       Note that a future version of fetchmail may remove To/Cc parsing!

       When fetchmail cannot deduce a recipient address that is local, and the
       intended  recipient  address was anyone other than fetchmail's invoking
       user, mail will get lost.  This is what  makes  the  multidrop  feature
       risky without proper envelope information.

       A  related  problem is that when you blind-copy a mail message, the Bcc
       information is carried only as envelope address (it's removed from  the
       headers  by  the  sending  mail server, so fetchmail can see it only if
       there is an X-0elope-To header).  Thus, blind-copying  to  someone  who
       gets  mail  over  a  fetchmail  multidrop link will fail unless the the
       mailserver host routinely writes X-Envelope-To or an equivalent  header
       into messages in your maildrop.

       In conclusion, mailing lists and Bcc'd mail can only work if the server
       you're fetching from (1) stores one copy of the message  per  recipient
       in  your  domain  and (2) records the envelope information in a special
       header (X-Original-To, Delivered-To, X-Envelope-To).


   Good Ways To Use Multidrop Mailboxes
       Multiple local names can be used to administer a mailing list from  the
       client side of a fetchmail collection.  Suppose your name is 'esr', and
       you want to both pick up your own mail  and  maintain  a  mailing  list
       called  (say)  "fetchmail-friends", and you want to keep the alias list
       on your client machine.

       On your server, you can alias 'fetchmail-friends' to  'esr';  then,  in
       your .fetchmailrc, declare 'to esr fetchmail-friends here'.  Then, when
       mail including 'fetchmail-friends' as a local address gets fetched, the
       list name will be appended to the list of recipients your SMTP listener
       sees.  Therefore it will undergo alias expansion locally.  Be  sure  to
       include  'esr'  in  the  local alias expansion of fetchmail-friends, or
       you'll never see mail sent only to the list.  Also be  sure  that  your
       listener  has  the  "me-too"  option  set (sendmail's -oXm command-line
       option or OXm declaration) so your name isn't removed from alias expan-
       sions in messages you send.

       This  trick  is not without its problems, however.  You'll begin to see
       this when a message comes in that is addressed only to a  mailing  list
       you  do not have declared as a local name.  Each such message will fea-
       ture an 'X-Fetchmail-Warning' header which is generated because  fetch-
       mail  cannot  find a valid local name in the recipient addresses.  Such
       messages default (as was described above) to being sent  to  the  local
       user  running fetchmail, but the program has no way to know that that's
       actually the right thing.


   Bad Ways To Abuse Multidrop Mailboxes
       Multidrop mailboxes and fetchmail serving multiple users in daemon mode
       do not mix.  The problem, again, is mail from mailing lists, which typ-
       ically does not have an individual recipient address  on  it.    Unless
       fetchmail can deduce an envelope address, such mail will only go to the
       account running fetchmail (probably root).   Also,  blind-copied  users
       are very likely never to see their mail at all.

       If  you're tempted to use fetchmail to retrieve mail for multiple users
       from a single mail drop via POP or IMAP, think again  (and  reread  the
       section  on  header and envelope addresses above).  It would be smarter
       to just let the mail sit in the mailserver's queue and use  fetchmail's
       ETRN  or ODMR modes to trigger SMTP sends periodically (of course, this
       means you have to poll more frequently  than  the  mailserver's  expiry
       period).  If you can't arrange this, try setting up a UUCP feed.

       If  you  absolutely must use multidrop for this purpose, make sure your
       mailserver writes an envelope-address header that  fetchmail  can  see.
       Otherwise you will lose mail and it will come back to haunt you.


   Speeding Up Multidrop Checking
       Normally, when multiple users are declared fetchmail extracts recipient
       addresses as described above and checks each host part with DNS to  see
       if it's an alias of the mailserver.  If so, the name mappings described
       in the "to ... here" declaration are done and the mail  locally  deliv-
       ered.

       This is a convenient but also slow method.  To speed it up, pre-declare
       mailserver aliases with 'aka'; these are checked before DNS lookups are
       done.   If you're certain your aka list contains all DNS aliases of the
       mailserver (and all MX names pointing at it - note this may change in a
       future  version)  you  can  declare  'no  dns'  to suppress DNS lookups
       entirely and only match against the aka list.


SOCKS
       Support for socks4/5 is a compile time configuration option. Once  com-
       piled  in, fetchmail will always use the socks libraries and configura-
       tion on your system, there are no run-time switches in fetchmail -  but
       you  can  still configure SOCKS: you can specify which SOCKS configura-
       tion file is used in the SOCKS_CONF environment variable.

       For instance, if you wanted to bypass the SOCKS  proxy  altogether  and
       have    fetchmail    connect    directly,    you    could   just   pass
       SOCKS_CONF=/dev/null in the environment, for example  (add  your  usual
       command line options - if any - to the end of this line):

       env SOCKS_CONF=/dev/null fetchmail


EXIT CODES
       To  facilitate  the  use  of fetchmail in shell scripts, an exit status
       code is returned to give an indication of what occurred during a  given
       connection.

       The exit codes returned by fetchmail are as follows:

       0      One  or more messages were successfully retrieved (or, if the -c
              option was selected, were found waiting but not retrieved).

       1      There was no mail awaiting retrieval.  (There may have been  old
              mail still on the server but not selected for retrieval.)

       2      An  error  was  encountered  when attempting to open a socket to
              retrieve mail.  If you don't know what a socket is, don't  worry
              about  it  -- just treat this as an 'unrecoverable error'.  This
              error can also be because a protocol fetchmail wants to  use  is
              not listed in /etc/services.

       3      The  user authentication step failed.  This usually means that a
              bad user-id, password, or APOP id was specified.  Or it may mean
              that you tried to run fetchmail under circumstances where it did
              not have standard input attached to a  terminal  and  could  not
              prompt for a missing password.

       4      Some sort of fatal protocol error was detected.

       5      There was a syntax error in the arguments to fetchmail.

       6      The run control file had bad permissions.

       7      There  was  an error condition reported by the server.  Can also
              fire if fetchmail timed out while waiting for the server.

       8      Client-side exclusion error.  This means fetchmail either  found
              another  copy of itself already running, or failed in such a way
              that it isn't sure whether another copy is running.

       9      The user authentication step failed because the server responded
              "lock  busy".  Try again after a brief pause!  This error is not
              implemented for all protocols, nor  for  all  servers.   If  not
              implemented  for  your server, "3" will be returned instead, see
              above.  May be returned when talking to qpopper or other servers
              that  can respond with "lock busy" or some similar text contain-
              ing the word "lock".

       10     The fetchmail run failed while trying to do an SMTP port open or
              transaction.

       11     Fatal  DNS error.  Fetchmail encountered an error while perform-
              ing a DNS lookup at startup and could not proceed.

       12     BSMTP batch file could not be opened.

       13     Poll terminated by a fetch limit (see the --fetchlimit option).

       14     Server busy indication.

       23     Internal error.  You should see a message on standard error with
              details.

       24 - 26, 28, 29
              These are internal codes and should not appear externally.

       When  fetchmail  queries  more than one host, return status is 0 if any
       query successfully retrieved mail. Otherwise the returned error  status
       is that of the last host queried.


FILES
       ~/.fetchmailrc
            default run control file

       ~/.fetchids
            default  location  of  file  recording  last message UIDs seen per
            host.

       ~/.fetchmail.pid
            lock file to help prevent concurrent runs (non-root mode).

       ~/.netrc
            your FTP run control file, which (if present) will be searched for
            passwords as a last resort before prompting for one interactively.

       /var/run/fetchmail.pid
            lock  file  to help prevent concurrent runs (root mode, Linux sys-
            tems).

       /etc/fetchmail.pid
            lock file to help prevent  concurrent  runs  (root  mode,  systems
            without /var/run).


ENVIRONMENT
       FETCHMAILUSER:  If the FETCHMAILUSER variable is set, it is used as the
       name of the calling user (default local  name)  for  purposes  such  as
       mailing  error notifications.  Otherwise, if either the LOGNAME or USER
       variable is correctly set (e.g. the corresponding UID matches the  ses-
       sion user ID) then that name is used as the default local name.  Other-
       wise getpwuid(3) must be able to retrieve a password entry for the ses-
       sion  ID (this elaborate logic is designed to handle the case of multi-
       ple names per userid gracefully).

       FETCHMAILHOME: If the environment variable FETCHMAILHOME is  set  to  a
       valid  and  existing  directory  name,  fetchmail will read $FETCHMAIL-
       HOME/fetchmailrc  (the  dot  is  missing  in  this  case),  $FETCHMAIL-
       HOME/.fetchids  and  $FETCHMAILHOME/.fetchmail.pid rather than from the
       user's home directory.  The .netrc file is always looked for in the the
       invoking user's home directory regardless of FETCHMAILHOME's setting.

       HOME_ETC:  If  the  HOME_ETC  variable  is  set,  fetchmail  will  read
       $HOME_ETC/.fetchmailrc instead of ~/.fetchmailrc.

       If HOME_ETC and FETCHMAILHOME are both set, HOME_ETC will be ignored.

       SOCKS_CONF: (only if SOCKS support is compiled  in)  this  variable  is
       used  by  the  socks  library  to  find out which configuration file it
       should read. Set this to /dev/null to bypass the SOCKS proxy.


SIGNALS
       If a fetchmail daemon is running as root, SIGUSR1 wakes it up from  its
       sleep  phase and forces a poll of all non-skipped servers. For compati-
       bility reasons, SIGHUP can also be used in 6.3.X but may not be  avail-
       able in future fetchmail versions.

       If fetchmail is running in daemon mode as non-root, use SIGUSR1 to wake
       it (this is so SIGHUP due to logout can retain the  default  action  of
       killing it).

       Running fetchmail in foreground while a background fetchmail is running
       will do whichever of these is appropriate to wake it up.


BUGS AND KNOWN PROBLEMS
       Please check the NEWS file that shipped with fetchmail for  more  known
       bugs than those listed here.

       Fetchmail  cannot  handle  user  names  that contain blanks after a "@"
       character, for instance "demonstr@ti on". These are rather uncommon and
       only  hurt when using UID-based --keep setups, so the 6.3.X versions of
       fetchmail won't be fixed.

       The assumptions that the DNS and in particular the  checkalias  options
       make  are  not  often sustainable. For instance, it has become uncommon
       for an MX server to be a POP3 or IMAP server at the same  time.  There-
       fore the MX lookups may go away in a future release.

       The  mda  and plugin options interact badly.  In order to collect error
       status from the MDA, fetchmail has to change its normal signal handling
       so  that  dead  plugin  processes don't get reaped until the end of the
       poll cycle.  This can cause resource starvation  if  too  many  zombies
       accumulate.   So  either  don't  deliver to a MDA using plugins or risk
       being overrun by an army of undead.

       The --interface option does not support IPv6 and it is doubtful  if  it
       ever  will,  since  there  is  no  portable way to query interface IPv6
       addresses.

       The RFC822 address  parser  used  in  multidrop  mode  chokes  on  some
       @-addresses  that  are  technically legal but bizarre.  Strange uses of
       quoting and embedded comments are likely to confuse it.

       In a message with multiple envelope headers, only  the  last  one  pro-
       cessed will be visible to fetchmail.

       Use  of  some  of  these protocols requires that the program send unen-
       crypted passwords over the TCP/IP connection to the  mailserver.   This
       creates a risk that name/password pairs might be snaffled with a packet
       sniffer or more sophisticated monitoring  software.   Under  Linux  and
       FreeBSD,  the  --interface  option  can  be used to restrict polling to
       availability of a specific interface device with a  specific  local  or
       remote  IP  address,  but snooping is still possible if (a) either host
       has a network device that can be opened in promiscuous mode, or (b) the
       intervening network link can be tapped.  We recommend the use of ssh(1)
       tunnelling to not only shroud your passwords  but  encrypt  the  entire
       conversation.

       Use  of  the  %F  or  %T escapes in an mda option could open a security
       hole, because they pass text manipulable by an attacker to a shell com-
       mand.  Potential shell characters are replaced by '_' before execution.
       The hole is further reduced by the fact that fetchmail temporarily dis-
       cards any suid privileges it may have while running the MDA.  For maxi-
       mum safety, however, don't use an mda command containing %F or %T  when
       fetchmail is run from the root account itself.

       Fetchmail's  method  of  sending bounces due to errors or spam-blocking
       and spam bounces requires that port 25 of localhost  be  available  for
       sending mail via SMTP.

       If  you  modify a ~/.fetchmailrc while a background instance is running
       and break the  syntax,  the  background  instance  will  die  silently.
       Unfortunately,  it  can't die noisily because we don't yet know whether
       syslog should be enabled.  On some systems, fetchmail dies quietly even
       if  there  is  no syntax error; this seems to have something to do with
       buggy terminal ioctl code in the kernel.

       The -f - option (reading a configuration from  stdin)  is  incompatible
       with the plugin option.

       The 'principal' option only handles Kerberos IV, not V.

       Interactively  entered  passwords are truncated after 63 characters. If
       you really need to use a longer password, you will have to use  a  con-
       figuration file.

       A  backslash  as  the  last  character  of a configuration file will be
       flagged as a syntax error rather than ignored.

       The BSMTP error handling is virtually nonexistent and may leave  broken
       messages behind.

       Send comments, bug reports, gripes, and the like to the fetchmail-devel
       list <fetchmail-develATlists.de>.  An HTML FAQ is  available  at
       the  fetchmail  home page; surf to http://fetchmail.berlios.de/ or do a
       WWW search for pages with 'fetchmail' in their titles.


AUTHOR
       Fetchmail is currently maintained by Matthias Andree and Rob Funk  with
       major  assistance  from  Sunil Shetye (for code) and Rob MacGregor (for
       the mailing lists).

       Most of the code is from Eric S. Raymond <esrATsnark.com>.   Too
       many other people to name here have contributed code and patches.

       This  program  is descended from and replaces popclient, by Carl Harris
       <ceharrisATmal.com>; the internals have become quite different, but some
       of  its  interface  design is directly traceable to that ancestral pro-
       gram.

       This manual page has been  improved  by  R. Hannes  Beinert  and  Hctor
       Garca.


SEE ALSO
       mutt(1), elm(1), mail(1), sendmail(8), popd(8), imapd(8), netrc(5)

       The fetchmail home page: <http://fetchmail.berlios.de/>;

       The maildrop home page: <http://www.courier-mta.org/maildrop/>;

APPLICABLE STANDARDS
       Note that this list is just a collection of references and not a state-
       ment as to the actual protocol conformance or  requirements  in  fetch-
       mail.

       SMTP/ESMTP:
            RFC  821,  RFC  2821,  RFC 1869, RFC 1652, RFC 1870, RFC 1983, RFC
            1985, RFC 2554.

       mail:
            RFC 822, RFC 2822, RFC 1123, RFC 1892, RFC 1894.

       POP2:
            RFC 937

       POP3:
            RFC 1081, RFC 1225, RFC 1460, RFC 1725, RFC 1734,  RFC  1939,  RFC
            1957, RFC 2195, RFC 2449.

       APOP:
            RFC 1939.

       RPOP:
            RFC 1081, RFC 1225.

       IMAP2/IMAP2BIS:
            RFC 1176, RFC 1732.

       IMAP4/IMAP4rev1:
            RFC  1730,  RFC  1731, RFC 1732, RFC 2060, RFC 2061, RFC 2195, RFC
            2177, RFC 2683.

       ETRN:
            RFC 1985.

       ODMR/ATRN:
            RFC 2645.

       OTP: RFC 1938.

       LMTP:
            RFC 2033.

       GSSAPI:
            RFC 1508.

       TLS: RFC 2595.



fetchmail                       fetchmail 6.3.8                   fetchmail(1)