Yolinux.com

fetchmail manpage

Search topic Section
Get manual page for the search topic
List all commands matching the search topic
List all topics in the manpage index

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 <proto> | --proto <proto> | --protocol <proto>
	      (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 <portnumber> | --service <servicename>
	      (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 <portnumber>
	      (Keyword: port) Obsolete version of --service that does not take
	      service  names.	Note: this option may be removed from a future
	      version.

       --principal <principal>
	      (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 <seconds> | --timeout <seconds>
	      (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 up  indefinitely  trying  to	 fetch
	      mail  from a down host.  This would be particularly annoying for
	      a fetchmail running in 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 <command>
	      (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 socks, SSL, ssh,	or  need  some	special	 fire-
	      walling  setup.	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 primitive, and these token must be bounded by  whitespace
	      or  beginning of string or end of string).  Fetchmail will write
	      to the plugin's stdin and read from the plugin's stdout.

       --plugout <command>
	      (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 <name> | --folder <name>
	      (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
	      protocol.	 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 <name>
	      (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 <name>
	      (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 <name>
	      (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  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 <directory>
	      (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).

       --sslfingerprint <fingerprint>
	      (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 <hosts> | --smtphost <hosts>
	      (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 <hosts>
	      (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 <domain> | --smtpaddress <domain>
	      (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 <user@domain>
	      (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 <nnn> | --antispam <nnn[, nnn]...>
	      (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 <command> | --mda <command>
	      (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 maildrop 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 run-
	      ning  as	root,  it  sets its user id to that of the target user
	      while delivering mail through an MDA.  Some  possible  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	deliv-
	      ery 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 like "sendmail -i -t" that dis-
	      patches on the contents of To/Cc/Bcc, it will create mail	 loops
	      and  bring  the  just  wrath  of many postmasters down upon your
	      head.  Also, do not try to combine multidrop mode	 with  an  MDA
	      such as maildrop that can only accept one address; you will lose
	      mail.

	      A word of warning: 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  though.
	      Using  maildrop(1)  is  usually much easier, and many users find
	      the filter syntax used by maildrop easier to understand.


       --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 <filename>
	      (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 <maxbytes> | --limit <maxbytes>
	      (Keyword: limit) Takes a maximum octet size argument.   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 without 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 <interval> | --warnings <interval>
	      (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 <count> | --batchlimit <count>
	      (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 <number> | --fetchlimit <number>
	      (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 <number>
	      (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 <number>
	      (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 <count> | --expunge <count>
	      (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 <name> | --user <name> | --username <name>
	      (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 <specification> | --interface <specification>
	      (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 <interface> | --monitor <interface>
	      (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 <type>
	      (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 <pathname> | --fetchmailrc <pathname>
	      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 <pathname> | --idfile <pathname>
	      (Keyword:	 idfile)  Specify  an alternate name for the .fetchids
	      file used to save POP3 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 <pathname>
	      (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
	      rewrite.	 (This	option	is  provided  to pacify people who are
	      paranoid 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 <line> | --envelope <line>
	      (Keyword: envelope; Multidrop only)
	      In the configuration file, an enhanced syntax is used:
	      envelope [<count>] <line>

	      This  option  changes  the header fetchmail assumes will carry a
	      copy of the mail's envelope address.  Normally this is  'X-Enve-
	      lope-To',	 but  as this header is not standard, practice varies.
	      See the discussion of multidrop address handling	below.	 As  a
	      special case, 'envelope "Received"' enables parsing of sendmail-
	      style Received lines.  This is the default, and it should not be
	      necessary	 unless	 you  have  globally disabled Received parsing
	      with 'no envelope' in the .fetchmailrc file.

	      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 <prefix> | --qvirtual <prefix>
	      (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-
	      name@userhost.userdom.dom.com'  having a 'Delivered-To:' line of
	      the form:

	      Delivered-To: mbox-userstr-username@userhost.example.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
       Microsoft Exchange) is supported. If you compile in the support, fetch-
       mail will try to perform an NTLM	 authentication	 (instead  of  sending
       over  the  password  en clair) whenever the server returns AUTH=NTLM in
       its capability 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.

       --sslcheck  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 <interval> or -d <interval> 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 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 <filename> or --logfile <filename> option (keyword: set logfile)
       is only effective when fetchmail is detached. 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 primarily useful for  debugging  con-
       figurations.  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 com-
       pressing 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 <file> 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 <name> 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 descriptions.  Note: the most  common  cause  of	syntax
       errors is mixing up user and server options.

       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:


       Keyword		   Opt	 Mode	Function
       --------------------------------------------------------------------
       set daemon	   -d		Set  a background poll interval in
					seconds.
       set postmaster			Give the name of  the  last-resort
					mail recipient (default: user run-
					ning  fetchmail,  "postmaster"	if
					run by the root user)
       set    bouncemail		Direct	error  mail  to the sender
					(default)
       set no bouncemail		Direct error  mail  to	the  local
					postmaster  (as	 per the 'postmas-
					ter' global option above).
       set no spambounce		Do not	bounce	spam-blocked  mail
					(default).




       set    spambounce		Bounce	blocked	 spam-blocked mail
					(as  per   the	 'antispam'   user
					option) back to the destination 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.
       set logfile	   -L		Name of a file to append error and
					status messages to.
       set idfile	   -i		Name  of  the  file  to	 store UID
					lists in.
       set    syslog			Do  error  logging  through   sys-
					log(3).
       set no syslog			Turn  off  error  logging  through
					syslog(3). (default)
       set properties			String value that  is  ignored	by
					fetchmail  (may	 be used by exten-
					sion scripts).

       Here are the legal server options:


       Keyword		Opt   Mode   Function
       -----------------------------------------------------------------
       via			     Specify DNS  name	of  mailserver,
				     overriding poll name
       proto[col]	-p	     Specify  protocol	(case  insensi-
				     tive):  POP2,  POP3,  IMAP,  APOP,
				     KPOP
       local[domains]	      m	     Specify  domain(s)	 to be regarded
				     as local
       port			     Specify TCP/IP service port (obso-
				     lete, use 'service' instead).
       service		-P	     Specify  service  name  (a numeric
				     value is also allowed and	consid-
				     ered a TCP/IP port number).
       auth[enticate]		     Set  authentication  type (default
				     'any')
       timeout		-t	     Server inactivity timeout in  sec-
				     onds (default 300)
       envelope		-E    m	     Specify   envelope-address	 header
				     name
       no envelope	      m	     Disable   looking	 for   envelope
				     address
       qvirtual		-Q    m	     Qmail  virtual  domain  prefix  to
				     remove from user name
       aka		      m	     Specify  alternate	 DNS  names  of
				     mailserver
       interface	-I	     specify  IP interface(s) that must
				     be up  for	 server	 poll  to  take
				     place
       monitor		-M	     Specify  IP address to monitor for
				     activity
       plugin			     Specify command through  which  to
				     make server connections.
       plugout			     Specify  command  through which to
				     make listener connections.
       dns		      m	     Enable DNS	 lookup	 for  multidrop
				     (default)
       no dns		      m	     Disable DNS lookup for multidrop
       checkalias	      m	     Do	 comparison  by	 IP address for
				     multidrop
       no checkalias	      m	     Do comparison  by	name  for  mul-
				     tidrop (default)


       uidl		-U	     Force   POP3  to  use  client-side
				     UIDLs (recommended)
       no uidl			     Turn off POP3 use	of  client-side
				     UIDLs (default)
       interval			     Only  check this site every N poll
				     cycles; N is a numeric argument.
       tracepolls		     Add poll  tracing	information  to
				     the Received header
       principal		     Set  Kerberos principal (only use-
				     ful with IMAP and kerberos)
       esmtpname		     Set name for  RFC2554  authentica-
				     tion to the ESMTP server.
       esmtppassword		     Set password for RFC2554 authenti-
				     cation to the ESMTP server.

       Here are the legal user options:


       Keyword		  Opt	Mode   Function
       -------------------------------------------------------------------
       user[name]	  -u	       Set remote user name  (local  user
				       name if name followed by 'here')
       is			       Connect	 local	and  remote  user
				       names
       to			       Connect	local  and  remote   user
				       names
       pass[word]		       Specify remote account password
       ssl			       Connect	to server over the speci-
				       fied  base  protocol   using   SSL
				       encryption
       sslcert			       Specify	file for client side pub-
				       lic SSL certificate
       sslkey			       Specify file for client side  pri-
				       vate SSL key
       sslproto			       Force ssl protocol for connection
       folder		  -r	       Specify remote folder to query
       smtphost		  -S	       Specify smtp host(s) to forward to
       fetchdomains		m      Specify	domains	 for  which  mail
				       should be fetched
       smtpaddress	  -D	       Specify	the  domain  to be put in
				       RCPT TO lines
       smtpname			       Specify the user and domain to  be
				       put in RCPT TO lines
       antispam		  -Z	       Specify	 what  SMTP  returns  are
				       interpreted as spam-policy blocks
       mda		  -m	       Specify MDA for local delivery
       bsmtp		  -o	       Specify BSMTP batch file to append
				       to
       preconnect		       Command to be executed before each
				       connection
       postconnect		       Command to be executed after  each
				       connection
       keep		  -k	       Don't  delete  seen  messages from
				       server (for POP3, uidl  is  recom-
				       mended)
       flush		  -F	       Flush  all  seen	 messages  before
				       querying (DANGEROUS)
       limitflush		       Flush   all   oversized	 messages
				       before querying
       fetchall		  -a	       Fetch all messages whether seen or
				       not
       rewrite			       Rewrite destination addresses  for
				       reply (default)
       stripcr			       Strip  carriage	returns from ends
				       of lines
       forcecr			       Force carriage returns at ends  of
				       lines


       pass8bits		       Force  BODY=8BITMIME to ESMTP lis-
				       tener
       dropstatus		       Strip Status and	 X-Mozilla-Status
				       lines out of incoming mail
       dropdelivered		       Strip  Delivered-To  lines  out of
				       incoming mail
       mimedecode		       Convert quoted-printable to  8-bit
				       in MIME messages
       idle			       Idle   waiting  for  new	 messages
				       after each poll (IMAP only)
       no keep		  -K	       Delete seen messages  from  server
				       (default)
       no flush			       Don't   flush  all  seen	 messages
				       before querying (default)
       no fetchall		       Retrieve	  only	  new	 messages
				       (default)
       no rewrite		       Don't rewrite headers
       no stripcr		       Don't   strip   carriage	  returns
				       (default)
       no forcecr		       Don't force  carriage  returns  at
				       EOL (default)
       no pass8bits		       Don't force BODY=8BITMIME to ESMTP
				       listener (default)
       no dropstatus		       Don't	drop	Status	  headers
				       (default)
       no dropdelivered		       Don't  drop  Delivered-To  headers
				       (default)
       no mimedecode		       Don't convert quoted-printable  to
				       8-bit in MIME messages (default)
       no idle			       Don't  idle  waiting  for new mes-
				       sages after each poll (IMAP only)
       limit		  -l	       Set message size limit
       warnings		  -w	       Set message size warning interval
       batchlimit	  -b	       Max # messages to forward in  sin-
				       gle connect
       fetchlimit	  -B	       Max  # messages to fetch in single
				       connect
       fetchsizelimit		       Max # message sizes  to	fetch  in
				       single transaction
       fastuidl			       Use binary search for first unseen
				       message (POP3 only)
       expunge		  -e	       Perform an expunge  on  every  #th
				       message (IMAP and POP3 only)
       properties		       String  value is ignored by fetch-
				       mail (may  be  used  by	extension
				       scripts)

       Remember that all user options must follow all server 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
       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.  Also, 'set dae-
       mon' 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
       necessary) 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
       different 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 Received: header (or whichever one is specified
       by the 'envelope' option) 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"

       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,  enclose  the
       string in double quotes.	 Thus:

	 poll mail.provider.net with proto pop3:
	       user "jsmith" there has password "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  (this  is  only
       likely  to  be  useful  when running fetchmail in daemon mode as root).
       The 'user' keyword leads off a user description, and every user	speci-
       fication 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:
	       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
       'joe@daffy.loonytoons.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.


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     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 associating hosts with last  message  IDs
	    seen (used only with newer RFC1939-compliant POP3 servers support-
	    ing the UIDL command).

       ~/.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
       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 session user ID)
       then that name is used as the  default  local  name.   Otherwise	 getp-
       wuid(3)	must  be  able to retrieve a password entry for the session ID
       (this elaborate logic is designed to handle the case of multiple	 names
       per userid gracefully).

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

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

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


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
       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.

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

       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.

       Send comments, bug reports, gripes, and the like to the fetchmail-devel
       list <fetchmail-devel@lists.berlios.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 <esr@snark.thyrsus.com>.   Too
       many other people to name here have contributed code and patches.

       This  program  is descended from and replaces popclient, by Carl Harris
       <ceharris@mal.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	Hector
       Garcia.


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 6.3.6			  fetchmail(1)
YoLinux.com Home Page
YoLinux Tutorial Index
Privacy Policy | Advertise with us | Feedback Form |
Unauthorized copying or redistribution prohibited.
    Bookmark and Share