2 .\" ** The above line should force tbl to be used as a preprocessor **
4 .\" Man page for fetchmail
6 .\" For license terms, see the file COPYING in this directory.
9 fetchmail \- fetch mail from a POP, IMAP, or ETRN-capable server
12 \fBfetchmail\fR [\fIoptions\fR] [\fImailserver...\fR]
18 is a mail-retrieval and forwarding utility; it fetches
19 mail from remote mailservers and forwards it to your local (client)
20 machine's delivery system. You can then handle the retrieved mail
21 using normal mail user agents such as \fIelm\fR(1) or \fIMail\fR(1).
22 The \fBfetchmail\fR utility can be run in a daemon mode to repeatedly
23 poll one or more systems at a specified interval.
27 program can gather mail from servers supporting any of the common
28 mail-retrieval protocols: POP2, POP3, IMAP2bis, IMAP4, and IMAPrev1.
29 It can also use the ESMTP ETRN extension. (The RFCs describing all
30 these protocols are listed at the end of this manual page.)
34 is primarily intended to be used over on-demand TCP/IP links (such as
35 SLIP or PPP connections), it may also be useful as a message transfer
36 agent for sites which refuse for security reasons to permit
37 (sender-initiated) SMTP transactions with sendmail.
39 As each message is retrieved \fIfetchmail\fR normally delivers it via SMTP to
40 port 25 on the machine it is running on (localhost), just as though it
41 were being passed in over a normal TCP/IP link. The mail will then be
42 delivered locally via your system's MDA (Mail Delivery Agent, usually
43 \fIsendmail\fR(8) but your system may use a different one such
44 as \fIsmail\fR, \fImmdf\fR, \fIexim\fR, or \fIqmail\fR). All the
45 delivery-control mechanisms (such as \fI.forward\fR files) normally
46 available through your system MDA and local delivery agents will
51 is available, it will assist you in setting up and editing a
52 fetchmailrc configuration. It runs under X and requires that the
53 language Python and the Tk toolkit be present on your system. If
54 you are first setting up fetchmail for single-user mode, it is
55 recommended that you use Novice mode. Expert mode provides
56 complete control of fetchmail configuration, including the
57 multidrop features. In either case, the `Autoprobe' button
58 will tell you the most capable protocol a given mailserver
59 supports, and warn you of potential problems with that server.
64 is controlled by command-line options and a run control file,
65 .IR ~/.fetchmailrc\fR ,
66 the syntax of which we describe in a later section (this file is what
67 the \fIfetchmailconf\fR program edits). Command-line options override
71 Each server name that you specify following the options on the
72 command line will be queried. If you don't specify any servers
73 on the command line, each `poll' entry in your
77 To facilitate the use of
79 in scripts and pipelines, it returns an appropriate exit code upon
80 termination -- see EXIT CODES below.
82 The following options modify the behavior of \fIfetchmail\fR. It is
83 seldom necessary to specify any of these once you have a
84 working \fI.fetchmailrc\fR file set up.
86 Almost all options have a corresponding keyword which can be used to
91 Some special options are not covered here, but are documented instead
92 in sections on AUTHENTICATION and DAEMON MODE which follow.
96 Displays the version information for your copy of
98 No mail fetch is performed.
99 Instead, for each server specified, all the option information
100 that would be computed if
102 were connecting to that server is displayed. Any non-printables in
103 passwords or other string names are shown as backslashed C-like
104 escape sequences. This option is useful for verifying that your
105 options are set the way you want them.
108 Return a status code to indicate whether there is mail waiting,
109 without actually fetching or deleting mail (see EXIT CODES below).
110 This option turns off daemon mode (in which it would be useless). It
111 doesn't play well with queries to multiple sites, and doesn't work
112 with ETRN. It will return a false positive if you leave read but
113 undeleted mail in your server mailbox and your fetch protocol can't
114 tell kept messages from new ones. This means it will work with IMAP,
115 not work with POP2, and may occasionally flake out under POP3.
118 Silent mode. Suppresses all progress/status messages that are
119 normally echoed to standard error during a fetch (but does not
120 suppress actual error messages). The --verbose option overrides this.
123 Verbose mode. All control messages passed between
125 and the mailserver are echoed to stderr. Overrides --silent.
126 Doubling this option (-v -v) causes extra diagnostic information
132 Retrieve both old (seen) and new messages from the mailserver. The
133 default is to fetch only messages the server has not marked seen.
134 Under POP3, this option also forces the use of RETR rather than TOP.
135 Note that POP2 retrieval behaves as though --all is always on (see
136 RETRIEVAL FAILURE MODES below) and this option does not work with ETRN.
140 Keep retrieved messages on the remote mailserver. Normally, messages
141 are deleted from the folder on the mailserver after they have been retrieved.
144 option causes retrieved messages to remain in your folder on the
145 mailserver. This option does not work with ETRN.
149 Delete retrieved messages from the remote mailserver. This
150 option forces retrieved mail to be deleted. It may be useful if
151 you have specified a default of \fBkeep\fR in your
152 \&\fI.fetchmailrc\fR. This option is forced on with ETRN.
155 POP3/IMAP only. Delete old (previously retrieved) messages from the mailserver
156 before retrieving new messages. This option does not work with ETRN.
157 Warning: if your local MTA hangs and fetchmail is aborted, the next
158 time you run fetchmail, it will delete mail that was never delivered to you.
159 What you probably want is the default setting: if you don't specify `-k', then
160 fetchmail will automatically delete messages after successful delivery.
161 .SS Protocol and Query Options
163 .B \-p, \--protocol <proto>
164 (Keyword: proto[col])
165 Specify the protocol to use when communicating with the remote
166 mailserver. If no protocol is specified, the default is AUTO.
168 may be one of the following:
171 Tries IMAP, POP3, and POP2 (skipping any of these for which support
172 has not been compiled in).
174 Post Office Protocol 2
176 Post Office Protocol 3
178 Use POP3 with MD5 authentication.
180 Use POP3 with RPOP authentication.
182 Use POP3 with Kerberos V4 preauthentication on port 1109.
184 Use POP3 with Demon Internet's SDPS extensions.
186 IMAP2bis, IMAP4, or IMAP4rev1 (\fIfetchmail\fR autodetects their capabilities).
188 IMAP4, or IMAP4rev1 (\fIfetchmail\fR autodetects their capabilities)
189 with RFC 1731 Kerberos v4 preauthentication.
191 IMAP4, or IMAP4rev1 (\fIfetchmail\fR autodetects their capabilities)
192 with RFC 1731 GSSAPI preauthentication.
194 IMAP4, or IMAP4rev1 (\fIfetchmail\fR autodetects their capabilities)
195 with RFC 2195 CRAM-MD5 authentication.
197 IMAP4, or IMAP4rev1 (\fIfetchmail\fR autodetects their capabilities)
198 with plain LOGIN authentication only, even if the server supports
201 Use the ESMTP ETRN option.
204 All these alternatives work in basically the same way (communicating
205 with standard server daemons to fetch mail already delivered to a
206 mailbox on the server) except ETRN. The ETRN mode allows you to ask a
207 compliant ESMTP server (such as BSD sendmail at release 8.8.0 or
208 higher) to immediately open a sender-SMTP connection to your
209 client machine and begin forwarding any items addressed to your client
210 machine in the server's queue of undelivered mail.
214 Force UIDL use (effective only with POP3). Force client-side tracking
215 of `newness' of messages (UIDL stands for ``unique ID listing'' and is
216 described in RFC1725). Use with `keep' to use a mailbox as a baby
217 news drop for a group of users.
219 .B \-P, --port <portnumber>
221 The port option permits you to specify a TCP/IP port to connect on.
222 This option will seldom be necessary as all the supported protocols have
223 well-established default port numbers.
225 .B \-t, --timeout <seconds>
227 The timeout option allows you to set a server-nonresponse
228 timeout in seconds. If a mailserver does not send a greeting message
229 or respond to commands for the given number of seconds,
230 \fIfetchmail\fR will hang up on it. Without such a timeout
231 \fIfetchmail\fR might hang up indefinitely trying to fetch mail from a
232 down host. This would be particularly annoying for a \fIfetchmail\fR
233 running in background. There is a default timeout which fetchmail -V
234 will report. If a given connection receives too many timeouts in
235 succession, fetchmail will consider it wedged and stop retrying,
236 the calkling user will be notified by email if this happens.
238 .B \--plugin <command>
240 The plugin option allows you to use an external program to establish the
241 TCP connection. This is useful if you want to use socks or need some
242 special firewalling setup. The program will be looked up in $PATH and
243 it will be passed two arguments: the name of the server and the name of
244 the port. Fetchmail will write to the plugin's stdin and read from
247 .B \--plugout <command>
249 Identical to the plugin option above, but this one is used for the SMTP
250 connections (which will probably not need it, so it has been separated
253 .B \-r <name>, --folder <name>
255 Causes a specified non-default mail folder on the mailserver (or
256 comma-separated list of folders) to be retrieved. The syntax of the
257 folder name is server-dependent. This option is not available under
262 Causes the connection to the mail server to be encrypted via SSL. Connect
263 to the server using the specified base protocol over a connection secured
264 by SSL. SSL support must be present at the server. If no port is
265 specified, the connection is attempted to the well known port of the SSL
266 version of the base protocol. This is generally a different port than the
267 port used by the base protocol. For imap, this is port 143 for the clear
268 protocol and port 993 for the SSL secured protocol.
272 Specifies the file name of the client side public SSL certificate. Some
273 SSL encrypted servers may require client side keys and certificates for
274 authentication. In most cases, this is optional. This specifies
275 the location of the public key certificate to be presented to the server
276 at the time the SSL session is established. It is not required (but may
277 be provided) if the server does not require it. Some servers may
278 require it, some servers may request it but not require it, and some
279 servers may not request it at all. It may be the same file
280 as the private key (combined key and certificate file) but this is not
285 Specifies the file name of the client side private SSL key. Some SSL
286 encrypted servers may require client side keys and certificates for
287 authentication. In most cases, this is optional. This specifies
288 the location of the private key used to sign transactions with the server
289 at the time the SSL session is established. It is not required (but may
290 be provided) if the server does not require it. Some servers may
291 require it, some servers may request it but not require it, and some
292 servers may not request it at all. It may be the same file
293 as the public key (combined key and certificate file) but this is not
294 recommended. If a password is required to unlock the key, it will be
295 prompted for at the time just prior to establishing the session to the
296 server. This can cause some complications in daemon mode.
297 .SS Delivery Control Options
299 .B \-S <hosts>, --smtphost <hosts>
300 (Keyword: smtp[host])
301 Specify a hunt list of hosts to forward mail to (one or more
302 hostnames, comma-separated). In ETRN mode, set the host that the
303 mailserver is asked to ship mail to. Hosts are tried in list order;
304 the first one that is up becomes the forwarding or ETRN target for the
305 current run. Normally, `localhost' is added to the end of the list as
306 an invisible default. However, when using ETRN mode or Kerberos
307 preauthentication, the FQDN of the machine running fetchmail is added to
308 the end of the list as an invisible default. Each hostname may have a
309 port number following the host name. The port number is separated from
310 the host name by a slash; the default port is 25 (or ``smtp'' under IPv6).
313 --smtphost server1,server2/2525,server3
316 .B \-D <domain>, --smtpaddress <domain>
317 (Keyword: smtpaddress)
318 Specify the domain to be put in RCPT TO lines shipped to SMTP. The
319 name of the SMTP server (as specified by --smtphost, or defaulted to
320 "localhost") is used when this is not specified.
322 .B \-Z <nnn>, --antispam <nnn[, nnn]...>
324 Specifies the list of numeric SMTP errors that are to be interpreted
325 as a spam-block response from the listener. A value of -1 disables
326 this option. For the command-line option, the list values should
329 .B \-m <command>, \--mda <command>
331 You can force mail to be passed to an MDA directly (rather than
332 forwarded to port 25) with the -mda or -m option. Be aware that this
333 disables some valuable resource-exhaustion checks and error handling
334 provided by SMTP listeners; it's not a good idea unless running an
335 SMTP listener is impossible. If \fIfetchmail\fR is running as root,
336 it sets its userid to that of the target user while delivering mail
337 through an MDA. Some possible MDAs are "/usr/sbin/sendmail -oem -f %F
338 %T", "/usr/bin/deliver" and "/usr/bin/procmail -d %T" (but the latter
339 is usually redundant as it's what SMTP listeners usually forward
340 to). Local delivery addresses will be inserted into the MDA command
341 wherever you place a %T; the mail message's From address will be
342 inserted where you place an %F. Do \fInot\fR use an MDA invocation
343 like "sendmail -oem -t" that dispatches on the contents of To/Cc/Bcc,
344 it will create mail loops and bring the just wrath of many postmasters
349 Cause delivery via LMTP (Local Mail Transfer Protocol). A service
350 port \fImust\fR be explicitly specified (with a slash suffix) on each
351 host in the smtphost hunt list) if this option is selected; the
352 default port 25 will (in accordance with RFC 2033) not be accepted.
354 .B \--bsmtp <filename>
356 Append fetched mail to a BSMTP file. This simply contains the SMTP
357 commands that would normally be generated by fetchmail when passing
358 mail to an SMTP listener daemon. An argument of `-' causes the mail
359 to be written to standard output. Note that fetchmail's
360 reconstruction of MAIL FROM and RCPT TO lines is not guaranteed
361 correct; the caveats discussed under THE USE AND ABUSE OF MULTIDROP
362 MAILBOXES below apply.
363 .SS Resource Limit Control Options
365 .B \-l <maxbytes>, --limit <maxbytes>
367 Takes a maximum octet size argument. Messages larger than this size
368 will not be fetched, not be marked seen, and will be left on the
369 server (in foreground sessions, the progress messages will note that
370 they are "oversized"). An explicit --limit of 0 overrides any limits
371 set in your run control file. This option is intended for those
372 needing to strictly control fetch time due to expensive and variable
373 phone rates. In daemon mode, oversize notifications are mailed to the
374 calling user (see the --warnings option). This option does not work
377 .B \-w <interval>, --warnings <interval>
379 Takes an interval in seconds. When you call
381 with a `limit' option in daemon mode, this controls the interval at
382 which warnings about oversized messages are mailed to the calling user
383 (or the user specified by the `postmaster' option). One such
384 notification is always mailed at the end of the the first poll that
385 the oversized message is detected. Thereafter, renotification is
386 suppressed until after the warning interval elapses (it will take
387 place at the end of the first following poll).
389 .B -b <count>, --batchlimit <count>
390 (Keyword: batchlimit)
391 Specify the maximum number of messages that will be shipped to an SMTP
392 listener before the connection is deliberately torn down and rebuilt
393 (defaults to 0, meaning no limit). An explicit --batchlimit of 0
394 overrides any limits set in your run control file. While
395 \fBsendmail\fR(8) normally initiates delivery of a message immediately
396 after receiving the message terminator, some SMTP listeners are not so
397 prompt. MTAs like \fIqmail\fR(8) and \fIsmail\fR(8) may wait till the
398 delivery socket is shut down to deliver. This may produce annoying
401 is processing very large batches. Setting the batch limit to some
402 nonzero size will prevent these delays.
403 This option does not work with ETRN.
405 .B -B <number>, --fetchlimit <number>
406 (Keyword: fetchlimit)
407 Limit the number of messages accepted from a given server in a single
408 poll. By default there is no limit. An explicit --fetchlimit of 0
409 overrides any limits set in your run control file.
410 This option does not work with ETRN.
412 .B -e <count>, --expunge <count>
414 Arrange for deletions to be made final after a given number of
415 messages. Under POP2 or POP3, fetchmail cannot make deletions final
416 without sending QUIT and ending the session -- with this option on,
417 fetchmail will break a long mail retrieval session into multiple
418 subsessions, sending QUIT after each sub-session. This is a good
419 defense against line drops on POP3 servers that do not do the
420 equivalent of a QUIT on hangup. Under IMAP,
422 normally issues an EXPUNGE command after each deletion in order to
423 force the deletion to be done immediately. This is safest when your
424 connection to the server is flaky and expensive, as it avoids
425 resending duplicate mail after a line hit. However, on large
426 mailboxes the overhead of re-indexing after every message can slam the
427 server pretty hard, so if your connection is reliable it is good to do
428 expunges less frequently. If you specify this option to an integer N,
431 to only issue expunges on every Nth delete. An argument of zero
432 suppresses expunges entirely (so no expunges at all will be done until
433 the end of run). This option does not work with ETRN.
434 .SS Authentication Options
436 .B \-u <name>, --username <name>
437 (Keyword: user[name])
438 Specifies the user identification to be used when logging in to the mailserver.
439 The appropriate user identification is both server and user-dependent.
440 The default is your login name on the client machine that is running
442 See USER AUTHENTICATION below for a complete description.
444 .B \-I <specification>, --interface <specification>
446 Require that a specific interface device be up and have a specific local
447 IP address (or range) before polling. Frequently
449 is used over a transient point-to-point TCP/IP link established directly
450 to a mailserver via SLIP or PPP. That is a relatively secure channel.
451 But when other TCP/IP routes to the mailserver exist (e.g. when the link
452 is connected to an alternate ISP), your username and password may be
453 vulnerable to snooping (especially when daemon mode automatically polls
454 for mail, shipping a clear password over the net at predictable
455 intervals). The --interface option may be used to prevent this. When
456 the specified link is not up or is not connected to a matching IP
457 address, polling will be skipped. The format is:
459 interface/iii.iii.iii.iii/mmm.mmm.mmm.mmm
461 The field before the first slash is the interface name (i.e. sl0, ppp0
462 etc.). The field before the second slash is the acceptable IP address.
463 The field after the second slash is a mask which specifies a range of
464 IP addresses to accept. If no mask is present 255.255.255.255 is
465 assumed (i.e. an exact match). This option is currently only supported
466 under Linux and FreeBSD. Please see the
468 section for below for FreeBSD specific information.
470 .B \-M <interface>, --monitor <interface>
472 Daemon mode can cause transient links which are automatically taken down
473 after a period of inactivity (e.g. PPP links) to remain up
474 indefinitely. This option identifies a system TCP/IP interface to be
475 monitored for activity. After each poll interval, if the link is up but
476 no other activity has occurred on the link, then the poll will be
477 skipped. This option is currently only supported under Linux and FreeBSD.
482 options to work for non root users under FreeBSD, the fetchmail binary
483 must be installed SGID kmem. This would be a security hole, but
484 fetchmail runs with the effective GID set to that of the kmem group
486 when interface data is being collected.
489 (Keyword: preauth[enticate])
490 This option permits you to specify a preauthentication type (see USER
491 AUTHENTICATION below for details). The possible values are
492 \&`\fBpassword\fR', `\fBkerberos_v5\fR' and `\fBkerberos\fR' (or, for
493 excruciating exactness, `\fBkerberos_v4\fR'). This option is provided
494 primarily for developers; choosing KPOP protocol automatically selects
495 Kerberos preauthentication, and all other alternatives use password
496 authentication (though APOP uses a generated one-time key as the
497 password and IMAP-K4 uses RFC1731 Kerberos v4 authentication). This
498 option does not work with ETRN.
499 .SS Miscellaneous Options
501 .B \-f <pathname>, --fetchmailrc <pathname>
502 Specify a non-default name for the
504 run control file. The pathname argument must be either "-" (a single
505 dash, meaning to read the configuration from standard input) or a
506 filename. Unless the --version option is also on, a named file
507 argument must have permissions no more open than 0600 (u=rw,g=,o=) or
510 .B \-i <pathname>, --idfile <pathname>
512 Specify an alternate name for the .fetchids file used to save POP3
516 (Keyword: no rewrite)
519 edits RFC-822 address headers (To, From, Cc, Bcc, and Reply-To) in
520 fetched mail so that any mail IDs local to the server are expanded to
521 full addresses (@ and the mailserver hostname are appended). This enables
522 replies on the client to get addressed correctly (otherwise your
523 mailer might think they should be addressed to local users on the
524 client machine!). This option disables the rewrite. (This option is
525 provided to pacify people who are paranoid about having an MTA edit
526 mail headers and want to know they can prevent it, but it is generally
527 not a good idea to actually turn off rewrite.)
528 When using ETRN, the rewrite option is ineffective.
530 .B -E <line>, --envelope <line>
532 This option changes the header
534 assumes will carry a copy of the mail's envelope address. Normally
535 this is `X-Envelope-To' but as this header is not standard, practice
536 varies. See the discussion of multidrop address handling below. As a
537 special case, `envelope "Received"' enables parsing of sendmail-style
538 Received lines. This is the default, and it should not be necessary
539 unless you have globally disabled Received parsing with `no envelope'
540 in the \fI.fetchmailrc\fR file.
542 .B -Q <prefix>, --qvirtual <prefix>
544 The string prefix assigned to this option will be removed from the user
545 name found in the header specified with the \fIenvelope\fR option
546 (\fIbefore\fR doing multidrop name mapping or localdomain checking,
547 if either is applicable). This option is useful if you are using
549 to collect the mail for an entire domain and your ISP (or your mail
550 redirection provider) is using qmail.
551 One of the basic features of qmail is the
555 message header. Whenever qmail delivers a message to a local mailbox
556 it puts the username and hostname of the envelope recipient on this
557 line. The major reason for this is to prevent mail loops. To set up
558 qmail to batch mail for a disconnected site the ISP-mailhost will have
559 normally put that site in its `Virtualhosts' control file so it will
560 add a prefix to all mail addresses for this site. This results in mail
561 sent to 'username@userhost.userdom.dom.com' having a
562 \&`Delivered-To:' line of the form:
564 Delivered-To: mbox-userstr-username@userhost.userdom.dom.com
566 The ISP can make the 'mbox-userstr-' prefix anything they choose
567 but a string matching the user host name is likely.
568 By using the option `envelope Delivered-To:' you can make fetchmail reliably
569 identify the original envelope recipient, but you have to strip the
570 `mbox-userstr-' prefix to deliver to the correct user.
571 This is what this option is for.
576 file, interpret any command-line options specified, and dump a
577 configuration report to standard output. The configuration report is
578 a data structure assignment in the language Python. This option
579 is meant to be used with an interactive
581 editor written in Python.
583 .SH USER AUTHENTICATION AND ENCRYPTION
584 Every mode except ETRN requires authentication of the client.
585 Normal user authentication in
587 is very much like the authentication mechanism of
589 The correct user-id and password depend upon the underlying security
590 system at the mailserver.
592 If the mailserver is a Unix machine on which you have an ordinary user
593 account, your regular login name and password are used with
595 If you use the same login name on both the server and the client machines,
596 you needn't worry about specifying a user-id with the
599 the default behavior is to use your login name on the client machine as the
600 user-id on the server machine. If you use a different login name
601 on the server machine, specify that login name with the
603 option. e.g. if your login name is 'jsmith' on a machine named 'mailgrunt',
608 fetchmail -u jsmith mailgrunt
610 The default behavior of
612 is to prompt you for your mailserver password before the connection is
613 established. This is the safest way to use
615 and ensures that your password will not be compromised. You may also specify
616 your password in your
618 file. This is convenient when using
620 in daemon mode or with scripts.
622 If you do not specify a password, and
624 cannot extract one from your
626 file, it will look for a
628 file in your home directory before requesting one interactively; if an
629 entry matching the mailserver is found in that file, the password will
630 be used. Fetchmail first looks for a match on poll name; if it finds none,
631 it checks for a match on via name. See the
633 man page for details of the syntax of the
635 file. (This feature may allow you to avoid duplicating password
636 information in more than one file.)
638 On mailservers that do not provide ordinary user accounts, your user-id and
639 password are usually assigned by the server administrator when you apply for
640 a mailbox on the server. Contact your server administrator if you don't know
641 the correct user-id and password for your mailbox account.
643 Early versions of POP3 (RFC1081, RFC1225) supported a crude form of
644 independent authentication using the
646 file on the mailserver side. Under this RPOP variant, a fixed
647 per-user ID equivalent to a password was sent in clear over a link to
648 a reserved port, with the command RPOP rather than PASS to alert the
649 server that it should do special checking. RPOP is supported
652 (you can specify `protocol RPOP' to have the program send `RPOP'
653 rather than `PASS') but its use is strongly discouraged. This
654 facility was vulnerable to spoofing and was withdrawn in RFC1460.
656 RFC1460 introduced APOP authentication. In this variant of POP3,
657 you register an APOP password on your server host (the program
658 to do this with on the server is probably called \fIpopauth\fR(8)). You
659 put the same password in your
663 logs in, it sends a cryptographically secure hash of your password and
664 the server greeting time to the server, which can verify it by
665 checking its authorization database.
667 If your \fIfetchmail\fR was built with Kerberos support and you specify
668 Kerberos preauthentication (either with --auth or the \fI.fetchmailrc\fR
669 option \fBauthenticate kerberos_v4\fR) it will try to get a Kerberos
670 ticket from the mailserver at the start of each query. Note: if
671 either the pollnane or via name is `hesiod', fetchmail will try to use
672 Hesiod to look up the mailserver.
674 If you use IMAP-K4, \fIfetchmail\fR will expect the IMAP server to have
675 RFC1731-conformant AUTHENTICATE KERBEROS_V4 capability, and will use it.
677 If you use IMAP-GSS, \fIfetchmail\fR will expect the IMAP server to have
678 RFC1731-conformant AUTHENTICATE GSSAPI capability, and will use it.
679 Currently this has only been tested over Kerberos V, so you're expected
680 to already have a ticket-granting ticket. You may pass a username different
681 from your principal name using the standard \fB--user\fR command or by
682 the \fI.fetchmailrc\fR option \fBuser\fR.
684 If your IMAP daemon returns the PREAUTH response in its greeting line,
685 fetchmail will notice this and skip the normal authentication step.
686 This could be useful, e.g. if you start imapd explicitly using ssh.
688 If you are using POP3, and the server issues a one-time-password
689 challenge conforming to RFC1938, \fIfetchmail\fR will use your
690 password as a pass phrase to generate the required response. This
691 avoids sending secrets over the net unencrypted.
693 Compuserve's RPA authentication (similar to APOP) is supported. If you
694 compile in the support, \fIfetchmail\fR will try to perform an RPA pass-phrase
695 authentication instead of sending over the password en clair if it
696 detects "@compuserve.com" in the hostname.
698 Microsoft's NTLM authentication (used by Microsoft Exchange) is
699 supported. If you compile in the support, \fIfetchmail\fR will try to
700 perform an NTLM authentication (instead of sending over the
701 password en clair) whenever the server returns AUTH=NTLM in its
702 capability response. Note: if you specify a user option value
703 that looks like `user@domain', the part to the left of the @ will
704 be passed as the username and the part to the right as the NTLM domain.
706 If you are using IPsec, the -T (--netsec) option can be used to pass
707 an IP security request to be used when outgoing IP connections are
708 initialized. You can also do this using the `netsec' server option
709 in the .fetchmailrc file. In either case, the option value is a
710 string in the format accepted by the net_security_strtorequest()
711 function of the inet6_apps library.
713 You can access SSL encrypted services by specifying the --ssl option.
714 You can also do this using the "ssl" server option in the .fetchmailrc
715 file. With SSL encryption enabled, queries are initiated over a connection
716 after negotiating an SSL session. Some services, such as POP3 and IMAP,
717 have different well known ports defined for the SSL encrypted services.
718 The encrypted ports will be selected automatically when SSL is enabled and
719 no explicit port is specified.
721 When connecting to an SSL encrypted server, the server presents a certificate
722 to the client for validation. The certificate is checked to verify that
723 the common name in the certificate matches the name of the server being
724 contacted and that the effective and expiration dates in the certificate
725 indicate that it is currently valid. If any of these checks fail, a warning
726 message is printed, but the connection continues. The server certificate
727 does not need to be signed by any specific Certifying Authority and may
728 be a "self-signed" certificate.
730 Some SSL encrypted servers may request a client side certificate. A client
731 side public SSL certificate and private SSL key may be specified. If
732 requested by the server, the client certificate is sent to the server for
733 validation. Some servers may require a valid client certificate and may
734 refuse connections if a certificate is not provided or if the certificate
735 is not valid. Some servers may require client side certificates be signed
736 by a recognized Certifying Authority. The format for the key files and
737 the certificate files is that required by the underlying SSL libraries
738 (OpenSSL in the general case).
742 .B --daemon <interval>
747 in daemon mode. You must specify a numeric argument which is a
748 polling interval in seconds.
752 puts itself in background and runs forever, querying each specified
753 host and then sleeping for the given polling interval.
759 will, therefore, poll all the hosts described in your
761 file (except those explicitly excluded with the `skip' verb) once
762 every fifteen minutes.
764 It is possible to set a polling interval
767 file by saying `set daemon <interval>', where <interval> is an
768 integer number of seconds. If you do this, fetchmail will always
769 start in daemon mode unless you override it with the command-line
770 option --daemon 0 or -d0.
772 Only one daemon process is permitted per user; in daemon mode,
774 makes a per-user lockfile to guarantee this.
776 Normally, calling fetchmail with a daemon in the background sends a
777 wakeup signal to the daemon, forcing it to poll mailservers
778 immediately. (The wakeup signal is SIGHUP if fetchmail is running as
779 root, SIGUSR1 otherwise.) The wakeup action also clears any `wedged'
780 flags indicating that connections have wedged due to failed
781 authentication or multiple timeouts.
785 will kill a running daemon process instead of waking it up (if there
788 notifies you). If the --quit option is the only command-line option,
789 that's all there is to it.
791 The quit option may also be mixed with other command-line options; its
792 effect is to kill any running daemon before doing what the other
793 options specify in combination with the rc file.
798 .B --logfile <filename>
799 option (keyword: set logfile) allows you to redirect status messages
800 emitted while detached into a specified logfile (follow the
801 option with the logfile name). The logfile is opened for append, so
802 previous messages aren't deleted. This is primarily useful for
803 debugging configurations.
807 option (keyword: set syslog) allows you to redirect status and error
808 messages emitted to the
810 system daemon if available.
811 Messages are logged with an id of \fBfetchmail\fR, the facility \fBLOG_MAIL\fR,
812 and priorities \fBLOG_ERR\fR, \fBLOG_ALERT\fR or \fBLOG_INFO\fR.
813 This option is intended for logging status and error messages which
814 indicate the status of the daemon and the results while fetching mail
816 Error messages for command line options and parsing the \fI.fetchmailrc\fR
817 file are still written to stderr, or to the specified log file.
820 option turns off use of
822 assuming it's turned on in the
832 or --nodetach option suppresses backgrounding and detachment of the
833 daemon process from its control terminal. This is primarily useful
834 for debugging. Note that this also causes the logfile option to be
835 ignored (though perhaps it shouldn't).
837 Note that while running in daemon mode polling a POP2 or IMAP2bis server,
838 transient errors (such as DNS failures or sendmail delivery refusals)
839 may force the fetchall option on for the duration of the next polling
840 cycle. This is a robustness feature. It means that if a message is
841 fetched (and thus marked seen by the mailserver) but not delivered
842 locally due to some transient error, it will be re-fetched during the
843 next poll cycle. (The IMAP logic doesn't delete messages until
844 they're delivered, so this problem does not arise.)
846 If you touch or change the
848 file while fetchmail is running in daemon mode, this will be detected
849 at the beginning of the next poll cycle. When a changed
851 is detected, fetchmail rereads it and restarts from scratch (using
852 exec(2); no state information is retained in the new instance). Note also
853 that if you break the
855 file's syntax, the new instance will softly and silently vanish away
858 .SH ADMINISTRATIVE OPTIONS
861 .B --postmaster <name>
862 option (keyword: set postmaster) specifies the last-resort username to
863 which multidrop mail is to be forwarded if no matching local recipient
864 can be found. Normally this is just the user who invoked fetchmail.
865 If the invoking user is root, then the default of this option is
866 the user `postmaster'.
870 option suppresses the normal action of bouncing errors back to the
871 sender in an RFC1894-conformant error message. If nobounce is on, the
872 message will go to the postmaster instead.
876 option (keyword: set invisible) tries to make fetchmail invisible.
877 Normally, fetchmail behaves like any other MTA would -- it generates a
878 Received header into each message describing its place in the chain of
879 transmission, and tells the MTA it forwards to that the mail came from
880 the machine fetchmail itself is running on. If the invisible option
881 is on, the Received header is suppressed and fetchmail tries to spoof
882 the MTA it forwards to into thinking it came directly from the
885 .SH RETRIEVAL FAILURE MODES
886 The protocols \fIfetchmail\fR uses to talk to mailservers are next to
887 bulletproof. In normal operation forwarding to port 25, no message is
888 ever deleted (or even marked for deletion) on the host until the SMTP
889 listener on the client has acknowledged to \fIfetchmail\fR that the
890 message has been accepted for delivery. When forwarding to an MDA,
891 however, there is more possibility of error (because there's no way
892 for fetchmail to get a reliable positive acknowledgement from the MDA).
894 The normal mode of \fIfetchmail\fR is to try to download only `new'
895 messages, leaving untouched (and undeleted) messages you have already
896 read directly on the server (or fetched with a previous \fIfetchmail
897 --keep\fR). But you may find that messages you've already read on the
898 server are being fetched (and deleted) even when you don't specify
899 --all. There are several reasons this can happen.
901 One could be that you're using POP2. The POP2 protocol includes no
902 representation of `new' or `old' state in messages, so \fIfetchmail\fR
903 must treat all messages as new all the time. But POP2 is obsolete, so
906 Under POP3, blame RFC1725. That version of the POP3 protocol
907 specification removed the LAST command, and some POP servers follow it
908 (you can verify this by invoking \fIfetchmail -v\fR to the mailserver
909 and watching the response to LAST early in the query). The
910 \fIfetchmail\fR code tries to compensate by using POP3's UID feature,
911 storing the identifiers of messages seen in each session until the
912 next session, in the \fI.fetchids\fR file. But this doesn't track
913 messages seen with other clients, or read directly with a mailer on
914 the host but not deleted afterward. A better solution would be to
917 Another potential POP3 problem might be servers that insert messages
918 in the middle of mailboxes (some VMS implementations of mail are
919 rumored to do this). The \fIfetchmail\fR code assumes that new
920 messages are appended to the end of the mailbox; when this is not true
921 it may treat some old messages as new and vice versa. The only
922 real fix for this problem is to switch to IMAP.
924 Yet another POP3 problem is that if they can't make tempfiles in the
925 user's home directory, some POP3 servers will hand back an
926 undocumented response that causes fetchmail to spuriously report "No
929 The IMAP code uses the presence or absence of the server flag \eSeen
930 to decide whether or not a message is new. Under Unix, it counts on
931 your IMAP server to notice the BSD-style Status flags set by mail user
932 agents and set the \eSeen flag from them when appropriate. All Unix
933 IMAP servers we know of do this, though it's not specified by the IMAP
934 RFCs. If you ever trip over a server that doesn't, the symptom will
935 be that messages you have already read on your host will look new to
936 the server. In this (unlikely) case, only messages you fetched with
937 \fIfetchmail --keep\fR will be both undeleted and marked old.
939 In ETRN mode, \fIfetchmail\fR does not actually retrieve messages;
940 instead, it asks the server's SMTP listener to start a queue flush
941 to the client via SMTP. Therefore it sends only undelivered messages.
944 Many SMTP listeners allow administrators to set up `spam filters' that
945 block unsolicited email from specified domains. A MAIL FROM or DATA line that
946 triggers this feature will elicit an SMTP response which
947 (unfortunately) varies according to the listener.
951 return an error code of 571. This return value
952 is blessed by RFC1893 as "Delivery not authorized, message refused".
954 According to current drafts of the replacement for RFC821, the correct
955 thing to return in this situation is 550 "Requested action not taken:
956 mailbox unavailable" (the draft adds "[E.g., mailbox not found, no
957 access, or command rejected for policy reasons].").
961 MTA returns 501 "Syntax error in parameters or arguments", but will
966 MTA runs 554 as an antispam response.
970 code recognizes and discards the message on any of a list of responses
971 that defaults to [571, 550, 501, 554] but can be set with the `antispam'
972 option. This is one of the
974 three circumstance under which fetchmail ever discards mail (the others
975 are the 552 and 553 errors described below, and the suppression of
976 multidropped messages with a message-ID already seen).
980 is fetching from an IMAP server, the antispam response will be detected and
981 the message rejected immediately after the headers have been fetched,
982 without reading the message body. Thus, you won't pay for downloading
985 Mail that is spam-blocked triggers an RFC1892 bounce message informing
986 the originator that we do not accept mail from it.
988 .SH SMTP/ESMTP ERROR HANDLING
989 Besides the spam-blocking described above,fetchmail takes special
990 actions on the following SMTP/ESMTP error responses
992 452 (insufficient system storage)
993 Leave the message in the server mailbox for later retrieval.
995 552 (message exceeds fixed maximum message size)
996 Delete the message from the server. Send bounce-mail to the originator.
998 553 (invalid sending domain)
999 Delete the message from the server. Send bounce-mail to the originator.
1001 Other errors trigger bounce mail back to the originator.
1003 .SH THE RUN CONTROL FILE
1004 The preferred way to set up fetchmail is to write a
1005 \&\fI.fetchmailrc\fR file in your home directory (you may do this
1006 directly, with a text editor, or indirectly via \fIfetchmailconf\fR).
1007 When there is a conflict between the command-line arguments and the
1008 arguments in this file, the command-line arguments take precedence.
1010 To protect the security of your passwords, when --version is not on
1011 your \fI~/.fetchmailrc\fR may not have more than 0600 (u=rw,g=,o=) permissions;
1013 will complain and exit otherwise.
1015 You may read the \fI.fetchmailrc\fR file as a list of commands to
1018 is called with no arguments.
1019 .SS Run Control Syntax
1021 Comments begin with a '#' and extend through the end of the line.
1022 Otherwise the file consists of a series of server entries or global
1023 option statements in a free-format, token-oriented syntax.
1025 There are four kinds of tokens: grammar keywords, numbers
1026 (i.e. decimal digit sequences), unquoted strings, and quoted strings.
1027 A quoted string is bounded by double quotes and may contain
1028 whitespace (and quoted digits are treated as a string). An unquoted
1029 string is any whitespace-delimited token that is neither numeric, string
1030 quoted nor contains the special characters `,', `;', `:', or `='.
1032 Any amount of whitespace separates tokens in server entries, but is
1033 otherwise ignored. You may use standard C-style escapes (\en, \et,
1034 \eb, octal, and hex) to embed non-printable characters or string
1035 delimiters in strings.
1037 Each server entry consists of one of the keywords `poll' or `skip',
1038 followed by a server name, followed by server options, followed by any
1039 number of user descriptions. Note: the most common cause of syntax
1040 errors is mixing up user and server options.
1042 For backward compatibility, the word `server' is a synonym for `poll'.
1044 You can use the noise keywords `and', `with',
1045 \&`has', `wants', and `options' anywhere in an entry to make
1046 it resemble English. They're ignored, but but can make entries much
1047 easier to read at a glance. The punctuation characters ':', ';' and
1048 \&',' are also ignored.
1051 The `poll' verb tells fetchmail to query this host when it is run with
1052 no arguments. The `skip' verb tells
1054 not to poll this host unless it is explicitly named on the command
1055 line. (The `skip' verb allows you to experiment with test entries
1056 safely, or easily disable entries for hosts that are temporarily down.)
1058 .SS Keyword/Option Summary
1059 Here are the legal options. Keyword suffixes enclosed in
1060 square brackets are optional. Those corresponding to command-line
1061 options are followed by `-' and the appropriate option letter.
1063 Here are the legal global options:
1067 Keyword Opt Function
1070 Set a background poll interval in seconds
1072 set postmaster \& T{
1073 Give the name of the last-resort mail recipient
1075 set no bouncemail \& T{
1076 Direct error mail to postmaster rather than sender
1079 Name of a file to dump error and status messages to
1082 Name of the file to store UID lists in
1085 Do error logging through syslog(3).
1088 Turn off error logging through syslog(3).
1090 set properties \& T{
1091 String value is ignored by fetchmail (may be used by extension scripts)
1095 Here are the legal server options:
1099 Keyword Opt Function
1102 Specify DNS name of mailserver, overriding poll name
1105 Specify protocol (case insensitive):
1106 POP2, POP3, IMAP, IMAP-K4, IMAP-GSS, APOP, KPOP
1109 Specify TCP/IP service port
1111 auth[enticate] -A T{
1112 Set preauthentication type (default `password')
1115 Server inactivity timeout in seconds (default 300)
1118 Specify envelope-address header name
1121 Disable looking for envelope address
1124 Qmail virtual domain prefix to remove from user name
1127 Specify alternate DNS names of mailserver
1130 specify IP interface(s) that must be up for server poll to take place
1133 Specify IP address to monitor for activity
1136 Specify command through which to make server connections.
1139 Specify command through which to make listener connections.
1142 Enable DNS lookup for multidrop (default)
1145 Disable DNS lookup for multidrop
1148 Do comparison by IP address for multidrop
1151 Do comparison by name for multidrop (default)
1154 Force POP3 to use client-side UIDLs
1157 Turn off POP3 use of client-side UIDLs (default)
1161 Here are the legal user options:
1165 Keyword Opt Function
1168 Set remote user name
1169 (local user name if name followed by `here')
1172 Connect local and remote user names
1175 Connect local and remote user names
1178 Specify remote account password
1181 Connect to server over the specified base protocol using SSL encryption
1184 Specify file for client side public SSL certificate
1187 Specify file for client side private SSL key
1190 Specify remote folder to query
1193 Specify smtp host(s) to forward to
1196 Specify the domain to be put in RCPT TO lines
1199 Specify what SMTP returns are interpreted as spam-policy blocks
1202 Specify MDA for local delivery
1205 Specify BSMTP batch file to append to
1208 Command to be executed before each connection
1211 Command to be executed after each connection
1214 Don't delete seen messages from server
1217 Flush all seen messages before querying
1220 Fetch all messages whether seen or not
1223 Rewrite destination addresses for reply (default)
1226 Strip carriage returns from ends of lines
1229 Force carriage returns at ends of lines
1232 Force BODY=8BITMIME to ESMTP listener
1235 Strip Status and X-Mozilla-Status lines out of incoming mail
1238 Convert quoted-printable to 8-bit in MIME messages
1241 Delete seen messages from server (default)
1244 Don't flush all seen messages before querying (default)
1247 Retrieve only new messages (default)
1250 Don't rewrite headers
1253 Don't strip carriage returns (default)
1256 Don't force carriage returns at EOL (default)
1259 Don't force BODY=8BITMIME to ESMTP listener (default)
1262 Don't drop Status headers (default)
1265 Don't convert quoted-printable to 8-bit in MIME messages (default)
1268 Set message size limit
1271 Set message size warning interval
1274 Max # messages to forward in single connect
1277 Max # messages to fetch in single connect
1280 Perform an expunge on every #th message (IMAP only)
1283 String value is ignored by fetchmail (may be used by extension scripts)
1287 Remember that all user options must \fIfollow\fR all server options.
1289 In the .fetchmailrc file, the `envelope' string argument may be
1290 preceded by a whitespace-separated number. This number, if specified,
1291 is the number of such headers to skip (that is, an argument of 1
1292 selects the second header of the given type). This is sometime useful
1293 for ignoring bogus Received headers created by an ISP's local delivery
1295 .SS Keywords Not Corresponding To Option Switches
1297 The `folder' and `smtphost' options (unlike their command-line
1298 equivalents) can take a space- or comma-separated list of names
1301 All options correspond to the obvious command-line arguments, except
1302 the following: `via', `interval', `aka', `is', `to', `dns'/`no dns',
1303 `checkalias'/`no checkalias', `password', `preconnect', `postconnect',
1304 `localdomains', `stripcr'/`no stripcr', `forcecr'/`no forcecr',
1305 `pass8bits'/`no pass8bits' `dropstatus/no dropstatus', `mimedecode/no
1306 mimedecode', and `no envelope'.
1308 The `via' option is for use with ssh, or if you want to have more
1309 than one configuration pointing at the same site. If it is present,
1310 the string argument will be taken as the actual DNS name of the
1311 mailserver host to query.
1312 This will override the argument of poll, which can then simply be a
1313 distinct label for the configuration (e.g. what you would give on the
1314 command line to explicitly query this host).
1315 If the `via' name is `localhost', the poll name will also still be
1316 used as a possible match in multidrop mode; otherwise the `via' name
1317 will be used instead and the poll name will be purely a label.
1319 The `interval' option (which takes a numeric argument) allows you to poll a
1320 server less frequently than the basic poll interval. If you say
1321 \&`interval N' the server this option is attached to will only be
1322 queried every N poll intervals.
1324 The `is' or `to' keywords associate the following local (client)
1325 name(s) (or server-name to client-name mappings separated by =) with
1326 the mailserver user name in the entry. If an is/to list has `*' as
1327 its last name, unrecognized names are simply passed through.
1329 A single local name can be used to support redirecting your mail when
1330 your username on the client machine is different from your name on the
1331 mailserver. When there is only a single local name, mail is forwarded
1332 to that local username regardless of the message's Received, To, Cc,
1333 and Bcc headers. In this case
1335 never does DNS lookups.
1337 When there is more than one local name (or name mapping) the
1338 \fIfetchmail\fR code does look at the Received, To, Cc, and Bcc
1339 headers of retrieved mail (this is `multidrop mode'). It looks for
1340 addresses with hostname parts that match your poll name or your `via',
1341 `aka' or `localdomains' options, and usually also for hostname parts
1342 which DNS tells it are aliases of the mailserver. See the discussion
1343 of `dns', `checkalias', `localdomains', and `aka' for details on how
1344 matching addresses are handled.
1346 If \fIfetchmail\fR cannot match any mailserver usernames or
1347 localdomain addresses, the mail will be bounced.
1348 Normally it will be bounced to the sender, but if `nobounce' is on
1349 it will go to the postmaster (which in turn defaults to being the
1352 The `dns' option (normally on) controls the way addresses from
1353 multidrop mailboxes are checked. On, it enables logic to check each
1354 host address that doesn't match an `aka' or `localdomains' declaration
1355 by looking it up with DNS. When a mailserver username is recognized
1356 attached to a matching hostname part, its local mapping is added to
1357 the list of local recipients.
1359 The `checkalias' option (normally off) extends the lookups performed
1360 by the `dns' keyword in multidrop mode, providing a way to cope with
1361 remote MTAs that identify themselves using their canonical name, while
1362 they're polled using an alias.
1363 When such a server is polled, checks to extract the envelope address
1366 reverts to delivery using the To/Cc/Bcc headers (See below
1367 `Header vs. Envelope addresses').
1368 Specifying this option instructs
1370 to retrieve all the IP addresses associated with both the poll name
1371 and the name used by the remote MTA and to do a comparison of the IP
1372 addresses. This comes in handy in situations where the remote server
1373 undergoes frequent canonical name changes, that would otherwise
1374 require modifications to the rcfile. `checkalias' has no effect if
1375 `no dns' is specified in the rcfile.
1377 The `aka' option is for use with multidrop mailboxes. It allows you
1378 to pre-declare a list of DNS aliases for a server. This is an
1379 optimization hack that allows you to trade space for speed. When
1381 while processing a multidrop mailbox, grovels through message headers
1382 looking for names of the mailserver, pre-declaring common ones can
1383 save it from having to do DNS lookups.
1385 The `localdomains' option allows you to declare a list of domains
1386 which fetchmail should consider local. When fetchmail is parsing
1387 address lines in multidrop modes, and a trailing segment of a host
1388 name matches a declared local domain, that address is passed through
1389 to the listener or MDA unaltered (local-name mappings are \fInot\fR
1392 If you are using `localdomains', you may also need to specify \&`no
1393 envelope', which disables \fIfetchmail\fR's normal attempt to deduce
1394 an envelope address from the Received line or X-Envelope-To header or
1395 whatever header has been previously set by `envelope'. If you set `no
1396 envelope' in the defaults entry it is possible to undo that in
1397 individual entries by using `envelope <string>'. As a special case,
1398 \&`envelope "Received"' restores the default parsing of
1401 The \fBpassword\fR option requires a string argument, which is the password
1402 to be used with the entry's server.
1404 The `preconnect' keyword allows you to specify a shell command to be
1405 executed just before each time
1407 establishes a mailserver connection. This may be useful if you are
1408 attempting to set up secure POP connections with the aid of
1410 If the command returns a nonzero status, the poll of that mailserver
1413 Similarly, the `postconnect' keyword similarly allows you to specify a
1414 shell command to be executed just after each time a mailserver
1415 connection is taken down.
1417 The `forcecr' option controls whether lines terminated by LF only are
1418 given CRLF termination before forwarding. Strictly speaking RFC821
1419 requires this, but few MTAs enforce the requirement it so this option
1420 is normally off (only one such MTA, qmail, is in significant use at
1423 The `stripcr' option controls whether carriage returns are stripped
1424 out of retrieved mail before it is forwarded. It is normally not
1425 necessary to set this, because it defaults to `on' (CR stripping
1426 enabled) when there is an MDA declared but `off' (CR stripping
1427 disabled) when forwarding is via SMTP. If `stripcr' and `forcecr' are
1428 both on, `stripcr' will override.
1430 The `pass8bits' option exists to cope with Microsoft mail programs that
1431 stupidly slap a "Content-Transfer-Encoding: 7bit" on everything. With
1432 this option off (the default) and such a header present,
1434 declares BODY=7BIT to an ESMTP-capable listener; this causes problems for
1435 messages actually using 8-bit ISO or KOI-8 character sets, which will
1436 be garbled by having the high bits of all characters stripped. If
1437 \&`pass8bits' is on,
1439 is forced to declare BODY=8BITMIME to any ESMTP-capable listener. If
1440 the listener is 8-bit-clean (as all the major ones now are) the right
1441 thing will probably result.
1443 The `dropstatus' option controls whether nonempty Status and
1444 X-Mozilla-Status lines are retained in fetched mail (the default) or
1445 discarded. Retaining them allows your MUA to see what messages (if
1446 any) were marked seen on the server. On the other hand, it can
1447 confuse some new-mail notifiers, which assume that anything with a
1448 Status line in it has been seen. (Note: the empty Status lines
1449 inserted by some buggy POP servers are unconditionally discarded.)
1451 The `mimedecode' option controls whether MIME messages using the
1452 quoted-printable encoding are automatically converted into pure 8-bit
1453 data. If you are delivering mail to an ESMTP-capable, 8-bit-clean
1454 listener (that includes all of the major MTAs like sendmail), then
1455 this will automatically convert quoted-printable message headers and
1456 data into 8-bit data, making it easier to understand when reading
1457 mail. If your e-mail programs know how to deal with MIME messages,
1458 then this option is not needed. The mimedecode option is off by
1459 default, because doing RFC2047 conversion on headers throws away
1460 character-set information and can lead to bad results if the encoding
1461 of the headers differs from the body encoding.
1463 The `properties' option is an extension mechanism. It takes a string
1464 argument, which is ignored by fetchmail itself. The string argument may be
1465 used to store configuration information for scripts which require it.
1466 In particular, the output of `--configdump' option will make properties
1467 associated with a user entry readily available to a Python script.
1469 .SS Miscellaneous Run Control Options
1470 The words `here' and `there' have useful English-like
1471 significance. Normally `user eric is esr' would mean that
1472 mail for the remote user `eric' is to be delivered to `esr',
1473 but you can make this clearer by saying `user eric there is esr here',
1474 or reverse it by saying `user esr here is eric there'
1476 Legal protocol identifiers for use with the `protocol' keyword are:
1483 imap-k4 (or IMAP-K4)
1484 imap-gss (or IMAP-GSS)
1485 imap-crammd5 (or IMAP-CRAMMD5)
1486 imap-login (or IMAP-LOGIN)
1491 Legal authentication types are `password' or `kerberos'. The former
1492 specifies authentication by normal transmission of a password (the
1493 password may be plaintext or subject to protocol-specific encryption
1494 as in APOP); the second tells \fIfetchmail\fR to try to get a Kerberos
1495 ticket at the start of each query instead, and send an arbitrary
1496 string as the password.
1498 Specifying `kpop' sets POP3 protocol over port 1109 with Kerberos V4
1499 preauthentication. These defaults may be overridden by later options.
1501 There are currently four global option statements; `set logfile'
1502 followed by a string sets the same global specified by --logfile. A
1503 command-line --logfile option will override this. Also, `set daemon'
1504 sets the poll interval as --daemon does. This can be overridden by a
1505 command-line --daemon option; in particular --daemon 0 can be used to
1506 force foreground operation. The `set postmater' statement sets the
1507 address to which multidrop mail defaults if there are no local
1508 matches. Finally, `set syslog' sends log messages to syslogd(8).
1510 .SH INTERACTION WITH RFC 822
1511 When trying to determine the originating address of a message,
1512 fetchmail looks through headers in the following order:
1522 The originating address is used for logging, and to set the MAIL FROM
1523 address when forwarding to SMTP. This order is intended to cope
1524 gracefully with receiving mailing list messages in multidrop mode. The
1525 intent is that if a local address doesn't exist, the bounce message
1526 won't be returned blindly to the author or to the list itself, but
1527 rather to the list manager (which is less annoying).
1529 In multidrop mode, destination headers are processed as follows:
1530 First, fetchmail looks for the Received: header (or whichever one is
1531 specified by the `envelope' option) to determine the local
1532 recipient address. If the mail is addressed to more than one recipient,
1533 the Received line won't contain any information regarding recipient addresses.
1535 Then fetchmail looks for the Resent-To:, Resent-Cc:, and Resent-Bcc:
1536 lines. If they exists, they should contain the final recipients and
1537 have precedence over their To:/Cc:/Bcc: counterparts. If the Resent-*
1538 lines doesn't exist, the To:, Cc:, Bcc: and Apparently-To: lines are
1539 looked for. (The presence of a Resent-To: is taken to imply that the
1540 person referred by the To: address has already received the original
1543 .SH CONFIGURATION EXAMPLES
1547 poll SERVERNAME protocol PROTOCOL username NAME password PASSWORD
1553 poll pop.provider.net protocol pop3 username "jsmith" password "secret1"
1556 Or, using some abbreviations:
1559 poll pop.provider.net proto pop3 user "jsmith" password "secret1"
1562 Multiple servers may be listed:
1565 poll pop.provider.net proto pop3 user "jsmith" pass "secret1"
1566 poll other.provider.net proto pop2 user "John.Smith" pass "My^Hat"
1569 Here's a version of those two with more whitespace and some noise words:
1572 poll pop.provider.net proto pop3
1573 user "jsmith", with password secret1, is "jsmith" here;
1574 poll other.provider.net proto pop2:
1575 user "John.Smith", with password "My^Hat", is "John.Smith" here;
1578 This version is much easier to read and doesn't cost significantly
1579 more (parsing is done only once, at startup time).
1582 If you need to include whitespace in a parameter string, enclose the
1583 string in double quotes. Thus:
1586 poll mail.provider.net with proto pop3:
1587 user "jsmith" there has password "u can't krak this"
1588 is jws here and wants mda "/bin/mail"
1591 You may have an initial server description headed by the keyword
1592 `defaults' instead of `poll' followed by a name. Such a record
1593 is interpreted as defaults for all queries to use. It may be overwritten
1594 by individual server descriptions. So, you could write:
1599 poll pop.provider.net
1601 poll mail.provider.net
1602 user "jjsmith" there has password "secret2"
1605 It's possible to specify more than one user per server (this is only
1606 likely to be useful when running fetchmail in daemon mode as root).
1607 The `user' keyword leads off a user description, and every user specification
1608 in a multi-user entry must include it. Here's an example:
1611 poll pop.provider.net proto pop3 port 3111
1612 user "jsmith" with pass "secret1" is "smith" here
1613 user jones with pass "secret2" is "jjones" here
1616 This associates the local username `smith' with the pop.provider.net
1617 username `jsmith' and the local username `jjones' with the
1618 pop.provider.net username `jones'.
1620 Here's what a simple retrieval configuration for a multi-drop mailbox
1624 poll pop.provider.net:
1625 user maildrop with pass secret1 to golux hurkle=happy snark here
1628 This says that the mailbox of account `maildrop' on the server is a
1629 multi-drop box, and that messages in it should be parsed for the
1630 server user names `golux', `hurkle', and `snark'. It further
1631 specifies that `golux' and `snark' have the same name on the
1632 client as on the server, but mail for server user `hurkle' should be
1633 delivered to client user `happy'.
1635 Here's an example of another kind of multidrop connection:
1638 poll pop.provider.net localdomains loonytoons.org toons.org:
1639 user maildrop with pass secret1 to esr * here
1642 This also says that the mailbox of account `maildrop' on the server is
1643 a multi-drop box. It tells fetchmail that any address in the
1644 loonytoons.org or toons.org domains (including subdomain addresses like
1645 `joe@daffy.loonytoons.org') should be passed through to the local SMTP
1646 listener without modification. Be careful of mail loops if you do this!
1648 Here's an example configuration using ssh. The queries go through an
1649 ssh connecting local port 1234 to port 110 on mailhost.net; the
1650 preconnect command sets up the ssh.
1653 poll mailhost.net via localhost port 1234 with proto pop3:
1654 preconnect "ssh -f -L 1234:mailhost.net:110
1655 mailhost.net sleep 20 </dev/null >/dev/null";
1658 .SH THE USE AND ABUSE OF MULTIDROP MAILBOXES
1659 Use the multiple-local-recipients feature with caution -- it can bite.
1660 Also note that all multidrop features are ineffective in ETRN mode.
1662 Also, note that in multidrop mode duplicate mails are suppressed.
1663 A piece of mail is considered duplicate if it has the same message-ID
1664 as the message immediately preceding. Such runs of messages may
1665 be generated when copies of a message addressed to multiple
1666 users are delivered to a multidrop box.
1668 .SS Header vs. Envelope addresses
1669 The fundamental problem is that by having your mailserver toss several
1670 peoples' mail in a single maildrop box, you may have thrown away
1671 potentially vital information about who each piece of mail was
1672 actually addressed to (the `envelope address', as opposed to the
1673 header addresses in the RFC822 To/Cc/Bcc headers). This `envelope
1674 address' is the address you need in order to reroute mail properly.
1678 can deduce the envelope address. If the mailserver MTA is
1680 and the item of mail had just one recipient, the MTA will have written
1681 a `by/for' clause that gives the envelope addressee into its Received
1682 header. But this doesn't work reliably for other MTAs, nor if there is
1683 more than one recipient. By default, \fIfetchmail\fR looks for
1684 envelope addresses in these lines; you can restore this default with
1685 -E "Received" or \&`envelope Received'.
1687 Alternatively, some SMTP listeners and/or mail servers insert a header
1688 in each message containing a copy of the envelope addresses. This
1689 header (when it exists) is often `X-Envelope-To'. Fetchmail's
1690 assumption about this can be changed with the -E or `envelope' option.
1691 Note that writing an envelope header of this kind exposes the names of
1692 recipients (including blind-copy recipients) to all receivers of the
1693 messages; it is therefore regarded by some administrators as a
1694 security/privacy problem.
1696 A slight variation of the `X-Envelope-To' header is the `Delivered-To' put
1697 by qmail to avoid mail loops. It will probably prefix the user name with a
1698 string that normally matches the user's domain. To remove this prefix you
1699 can use the -Q or `qvirtual' option.
1701 Sometimes, unfortunately, neither of these methods works. When they
1702 all fail, fetchmail must fall back on the contents of To/Cc/Bcc
1703 headers to try to determine recipient addressees -- and these are not
1704 reliable. In particular, mailing-list software often ships mail with
1705 only the list broadcast address in the To header.
1709 cannot deduce a recipient address that is local, and the intended
1710 recipient address was anyone other than fetchmail's invoking user,
1711 mail will get lost. This is what makes the multidrop feature risky.
1713 A related problem is that when you blind-copy a mail message, the Bcc
1714 information is carried \fIonly\fR as envelope address (it's not put
1715 in the headers fetchmail can see unless there is an X-Envelope
1716 header). Thus, blind-copying to someone who gets mail over a
1717 fetchmail link will fail unless the the mailserver host routinely
1718 writes X-Envelope or an equivalent header into messages in your maildrop.
1720 .SS Good Ways To Use Multidrop Mailboxes
1721 Multiple local names can be used to administer a mailing list from the
1722 client side of a \fIfetchmail\fR collection. Suppose your name is
1723 \&`esr', and you want to both pick up your own mail and maintain a mailing
1724 list called (say) "fetchmail-friends", and you want to keep the alias
1725 list on your client machine.
1727 On your server, you can alias \&`fetchmail-friends' to `esr'; then, in
1728 your \fI.fetchmailrc\fR, declare \&`to esr fetchmail-friends here'.
1729 Then, when mail including `fetchmail-friends' as a local address
1730 gets fetched, the list name will be appended to the list of
1731 recipients your SMTP listener sees. Therefore it will undergo alias
1732 expansion locally. Be sure to include `esr' in the local alias
1733 expansion of fetchmail-friends, or you'll never see mail sent only to
1734 the list. Also be sure that your listener has the "me-too" option set
1735 (sendmail's -oXm command-line option or OXm declaration) so your name
1736 isn't removed from alias expansions in messages you send.
1738 This trick is not without its problems, however. You'll begin to see
1739 this when a message comes in that is addressed only to a mailing list
1740 you do \fInot\fR have declared as a local name. Each such message
1741 will feature an `X-Fetchmail-Warning' header which is generated
1742 because fetchmail cannot find a valid local name in the recipient
1743 addresses. Such messages default (as was described above) to being
1744 sent to the local user running
1746 but the program has no way to know that that's actually the right thing.
1748 .SS Bad Ways To Abuse Multidrop Mailboxes
1749 Multidrop mailboxes and
1751 serving multiple users in daemon mode do not mix. The problem, again, is
1752 mail from mailing lists, which typically does not have an individual
1753 recipient address on it. Unless
1755 can deduce an envelope address, such mail will only go to the account
1756 running fetchmail (probably root). Also, blind-copied users are very
1757 likely never to see their mail at all.
1759 If you're tempted to use
1761 to retrieve mail for multiple users from a single mail drop via POP or
1762 IMAP, think again (and reread the section on header and envelope
1763 addresses above). It would be smarter to just let the mail sit in the
1764 mailserver's queue and use fetchmail's ETRN mode to trigger SMTP sends
1765 periodically (of course, this means you have to poll more frequently
1766 than the mailserver's expiry period). If you can't arrange this, try
1767 setting up a UUCP feed.
1769 If you absolutely \fImust\fR use multidrop for this purpose, make sure
1770 your mailserver writes an envelope-address header that fetchmail can
1771 see. Otherwise you \fIwill\fR lose mail and it \fIwill\fR come back
1774 .SS Speeding Up Multidrop Checking
1775 Normally, when multiple user are declared
1777 extracts recipient addresses as described above and checks each host
1778 part with DNS to see if it's an alias of the mailserver. If so, the
1779 name mappings described in the to ... here declaration are done and
1780 the mail locally delivered.
1782 This is the safest but also slowest method. To speed it up,
1783 pre-declare mailserver aliases with `aka'; these are checked before
1784 DNS lookups are done. If you're certain your aka list contains
1786 DNS aliases of the mailserver (and all MX names pointing at it)
1787 you can declare `no dns' to suppress DNS lookups entirely and
1788 \fIonly\fR match against the aka list.
1791 To facilitate the use of
1793 in shell scripts, an exit code is returned to give an indication
1794 of what occurred during a given connection.
1796 The exit codes returned by
1800 One or more messages were successfully retrieved (or, if the -c option
1801 was selected, were found waiting but not retrieved).
1803 There was no mail awaiting retrieval. (There may have been old mail still
1804 on the server but not selected for retrieval.)
1806 An error was encountered when attempting to open a socket to retrieve
1807 mail. If you don't know what a socket is, don't worry about it --
1808 just treat this as an 'unrecoverable error'.
1810 The user authentication step failed. This usually means that a bad
1811 user-id, password, or APOP id was specified.
1813 Some sort of fatal protocol error was detected.
1815 There was a syntax error in the arguments to
1818 The run control file had bad permissions.
1820 There was an error condition reported by the server. Can also
1823 timed out while waiting for the server.
1825 Client-side exclusion error. This means
1827 either found another copy of itself already running, or failed in such
1828 a way that it isn't sure whether another copy is running.
1830 The user authentication step failed because the server responded "lock
1831 busy". Try again after a brief pause! This error is not implemented
1832 for all protocols, nor for all servers. If not implemented for your
1833 server, "3" will be returned instead, see above. May be returned when
1834 talking to qpopper or other servers that can respond with "lock busy"
1835 or some similar text containing the word "lock".
1839 run failed while trying to do an SMTP port open or transaction.
1841 Fatal DNS error. Fetchmail encountered an error while performing
1842 a DNS lookup at startup and could not proceed.
1844 BSMTP batch file could not be opened.
1846 Poll terminated by a fetch limit (see the --fetchlimit option).
1848 Internal error. You should see a message on standard error with
1853 queries more than one host, return status is 0 if \fIany\fR query
1854 successfully retrieved mail. Otherwise the returned error status is
1855 that of the last host queried.
1858 Eric S. Raymond <esr@snark.thyrsus.com>. Too many other people to
1859 name here have contributed code and patches.
1860 This program is descended from and replaces
1862 by Carl Harris <ceharris@mal.com>; the internals have become quite different,
1863 but some of its interface design is directly traceable to that
1869 default run control file
1872 default location of file associating hosts with last message IDs seen
1873 (used only with newer RFC1725-compliant POP3 servers supporting the
1877 your FTP run control file, which (if present) will be searched for
1878 passwords as a last resort before prompting for one interactively.
1881 lock file to help prevent concurrent runs (non-root mode).
1883 /var/run/fetchmail.pid
1884 lock file to help prevent concurrent runs (root mode, Linux systems).
1887 lock file to help prevent concurrent runs (root mode, systems without /var/run).
1890 If either the LOGNAME or USER and the variable is correctly set
1891 (e.g. the corresponding UID matches the session user ID) then that
1892 name is used as the default local name. Otherwise \fBgetpwuid\fR(3)
1893 must be able to retrieve a password entry for the session ID (this
1894 elaborate logic is designed to handle the case of multiple names per
1900 daemon is running as root, SIGHUP wakes it up from its sleep phase and
1901 forces a poll of all non-skipped servers (this is in accordance with
1902 the usual conventions for system daemons).
1906 is running in daemon mode as non-root, use SIGUSR1 to wake it (this is
1907 so SIGHUP due to logout can retain the default action of killing it).
1911 in foreground while a background fetchmail is running will do
1912 whichever of these is appropriate to wake it up.
1914 .SH BUGS AND KNOWN PROBLEMS
1915 The RFC822 address parser used in multidrop mode chokes on some
1916 @-addresses that are technically legal but bizarre. Strange uses of
1917 quoting and embedded comments are likely to confuse it.
1919 In a message with multiple envelope headers, only the last one
1920 processed will be visible to fetchmail. To get around this, use a
1921 mailserver-side filter that consolidates the contents of all envelope
1922 headers into a single one (procmail, mailagent, or maildrop can be
1923 orogrammed to do this fairly easily).
1925 Use of any of the supported protocols other than POP3 with OTP or RPA,
1926 APOP, KPOP, IMAP-K4, IMAP-GSS, IMAP-CRAMMD5, or ETRN requires that the
1927 program send unencrypted passwords over the TCP/IP connection to the
1928 mailserver. This creates a risk that name/password pairs might be
1929 snaffled with a packet sniffer or more sophisticated monitoring
1930 software. Under Linux and FreeBSD, the --interface option can be used
1931 to restrict polling to availability of a specific interface device
1932 with a specific local IP address, but snooping is still possible if
1933 (a) either host has a network device that can be opened in promiscuous
1934 mode, or (b) the intervening network link can be tapped.
1936 Use of the %F or %T escapes in an mda option could open a security
1937 hole, because they pass text manipulable by an attacker to a shell
1938 command. Potential shell characters are replaced by `_' before
1939 execution. The hole is further reduced by the fact that fetchmail
1940 temporarily discards any suid privileges it may have while running the
1941 MDA. For maximum safety, however, don't use an mda command containing
1942 %F or %T when fetchmail is run from the root account itself.
1944 Fetchmail's method of sending bouncemail requires that port 25 of localhost
1945 be available for sending mail via SMTP.
1947 Send comments, bug reports, gripes, and the like to the
1948 fetchmail-friends list <fetchmail-friends@ccil.org>. An HTML FAQ is
1949 available at the fetchmail home page; surf to
1950 http://www.tuxedo.org/~esr/fetchmail or do a WWW search for pages with
1951 `fetchmail' in their titles.
1954 mutt(1), elm(1), mail(1), sendmail(8), popd(8), imapd(8)
1955 .SH APPLICABLE STANDARDS
1958 RFC 821, RFC 1869, RFC 1652, RFC 1870, RFC1983, RFC 1985
1961 RFC 822, RFC 1892, RFC1894
1967 RFC 1081, RFC 1225, RFC 1460, RFC 1725, RFC 1939, RFC 2449
1970 RFC 1460, RFC 1725, RFC 1939
1979 RFC 1730, RFC 1731, RFC 1732, RFC 2060, RFC 2061, RFC 2195
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