2 .\" ** The above line should force tbl to be used as a preprocessor **
4 .\" Manual page in man(7) format with tbl(1) macros for fetchmail
6 .\" For license terms, see the file COPYING in this directory.
8 .TH fetchmail 1 "fetchmail 6.3.7" "fetchmail" "fetchmail reference manual"
10 fetchmail \- fetch mail from a POP, IMAP, ETRN, or ODMR-capable server
13 \fBfetchmail\fR [\fIoption...\fR] [\fImailserver...\fR]
19 is a mail-retrieval and forwarding utility; it fetches mail from
20 remote mailservers and forwards it to your local (client) machine's
21 delivery system. You can then handle the retrieved mail using normal
22 mail user agents such as \fImutt\fR(1), \fIelm\fR(1) or \fIMail\fR(1).
23 The \fIfetchmail\fR utility can be run in a daemon mode to repeatedly
24 poll one or more systems at a specified interval.
28 program can gather mail from servers supporting any of the common
29 mail-retrieval protocols: POP2 (legacy, to be removed from future
30 release), POP3, IMAP2bis, IMAP4, and IMAP4rev1.
31 It can also use the ESMTP ETRN extension and ODMR. (The RFCs describing all
32 these protocols are listed at the end of this manual page.)
36 is primarily intended to be used over on-demand TCP/IP links (such as
37 SLIP or PPP connections), it may also be useful as a message transfer
38 agent for sites which refuse for security reasons to permit
39 (sender-initiated) SMTP transactions with sendmail.
43 is used with a POP or an IMAP server, it has two fundamental modes of
44 operation for each user account from which it retrieves mail:
45 \fIsingledrop\fR- and \fImultidrop\fR-mode. In singledrop-mode,
47 assumes that all messages in the user's account are intended for a single
48 recipient. An individual mail message will not be inspected for recipient
49 information, rather, the identity of the recipient will either default to
50 the local user currently executing \fIfetchmail\fR,
51 or else will need to be explicitly specified in the configuration file.
52 Singledrop-mode is used when the fetchmailrc configuration contains at
53 most a single local user specification for a given server account.
57 is not able to assume that there is only a single recipient, but rather
58 that the mail server account actually contains mail intended for any
59 number of different recipients. Therefore,
61 must attempt to deduce the proper "envelope recipient" from the mail
62 headers of each message. In this mode of operation,
64 almost resembles an MTA, however it is important to note that neither
65 the POP nor IMAP protocols were intended for use in this fashion, and
66 hence envelope information is often not directly available. Instead,
68 must resort to a process of informed guess-work in an attempt to
69 discover the true envelope recipient of a message, unless the ISP stores
70 the envelope information in some header (not all do). Even if this
71 information is present in the headers, the process can
72 be error-prone and is dependent upon the specific mail server used
73 for mail retrieval. Multidrop-mode is used when more than one local
74 user is specified for a particular server account in the configuration
75 file. Note that the forgoing discussion of singledrop- and
76 multidrop-modes does not apply to the ESMTP ETRN or ODMR retrieval
77 methods, since they are based upon the SMTP protocol which
78 specifically provides the envelope recipient to \fIfetchmail\fR.
80 As each message is retrieved, \fIfetchmail\fR normally delivers it via SMTP to
81 port 25 on the machine it is running on (localhost), just as though it
82 were being passed in over a normal TCP/IP link. \fIfetchmail\fR provides
83 the SMTP server with an envelope recipient derived in the manner described
84 previously. The mail will then be
85 delivered locally via your system's MDA (Mail Delivery Agent, usually
86 \fIsendmail\fR(8) but your system may use a different one such
87 as \fIsmail\fR, \fImmdf\fR, \fIexim\fR, \fIpostfix\fR, or \fIqmail\fR). All the
88 delivery-control mechanisms (such as \fI.forward\fR files) normally
89 available through your system MDA and local delivery agents will
90 therefore work automatically.
92 If no port 25 listener is available, but your fetchmail configuration
93 was told about a reliable local MDA, it will use that MDA for local
98 is available, it will assist you in setting up and editing a
99 fetchmailrc configuration. It runs under the X window system and
100 requires that the language Python and the Tk toolkit be present on your
101 system. If you are first setting up fetchmail for single-user mode, it
102 is recommended that you use Novice mode. Expert mode provides complete
103 control of fetchmail configuration, including the multidrop features.
104 In either case, the 'Autoprobe' button will tell you the most capable
105 protocol a given mailserver supports, and warn you of potential problems
108 .SH GENERAL OPERATION
111 is controlled by command-line options and a run control file,
112 .IR ~/.fetchmailrc\fR ,
113 the syntax of which we describe in a later section (this file is what
114 the \fIfetchmailconf\fR program edits). Command-line options override
118 Each server name that you specify following the options on the
119 command line will be queried. If you don't specify any servers
120 on the command line, each 'poll' entry in your
122 file will be queried.
124 To facilitate the use of
126 in scripts and pipelines, it returns an appropriate exit code upon
127 termination -- see EXIT CODES below.
129 The following options modify the behavior of \fIfetchmail\fR. It is
130 seldom necessary to specify any of these once you have a
131 working \fI.fetchmailrc\fR file set up.
133 Almost all options have a corresponding keyword which can be used to
138 Some special options are not covered here, but are documented instead
139 in sections on AUTHENTICATION and DAEMON MODE which follow.
143 Displays the version information for your copy of
145 No mail fetch is performed.
146 Instead, for each server specified, all the option information
147 that would be computed if
149 were connecting to that server is displayed. Any non-printables in
150 passwords or other string names are shown as backslashed C-like
151 escape sequences. This option is useful for verifying that your
152 options are set the way you want them.
155 Return a status code to indicate whether there is mail waiting,
156 without actually fetching or deleting mail (see EXIT CODES below).
157 This option turns off daemon mode (in which it would be useless). It
158 doesn't play well with queries to multiple sites, and doesn't work
159 with ETRN or ODMR. It will return a false positive if you leave read but
160 undeleted mail in your server mailbox and your fetch protocol can't
161 tell kept messages from new ones. This means it will work with IMAP,
162 not work with POP2, and may occasionally flake out under POP3.
165 Silent mode. Suppresses all progress/status messages that are
166 normally echoed to standard output during a fetch (but does not
167 suppress actual error messages). The \-\-verbose option overrides this.
170 Verbose mode. All control messages passed between
172 and the mailserver are echoed to stdout. Overrides \-\-silent.
173 Doubling this option (\-v \-v) causes extra diagnostic information
177 .B \-a | \-\-all | (since v6.3.3) \-\-fetchall
178 (Keyword: fetchall, since v3.0)
179 Retrieve both old (seen) and new messages from the mailserver. The
180 default is to fetch only messages the server has not marked seen.
181 Under POP3, this option also forces the use of RETR rather than TOP.
182 Note that POP2 retrieval behaves as though \-\-all is always on (see
183 RETRIEVAL FAILURE MODES below) and this option does not work with ETRN
184 or ODMR. While the \-a and \-\-all command-line and fetchall rcfile
185 options have been supported for a long time, the \-\-fetchall
186 command-line option was added in v6.3.3.
190 Keep retrieved messages on the remote mailserver. Normally, messages
191 are deleted from the folder on the mailserver after they have been retrieved.
192 Specifying the \fBkeep\fR option causes retrieved messages to remain in
193 your folder on the mailserver. This option does not work with ETRN or
194 ODMR. If used with POP3, it is recommended to also specify the \-\-uidl
195 option or uidl keyword.
199 Delete retrieved messages from the remote mailserver. This
200 option forces retrieved mail to be deleted. It may be useful if
201 you have specified a default of \fBkeep\fR in your
202 \&\fI.fetchmailrc\fR. This option is forced on with ETRN and ODMR.
205 POP3/IMAP only. This is a dangerous option and can cause mail loss when
206 used improperly. It deletes old (seen) messages from the mailserver
207 before retrieving new messages. \fBWarning:\fR This can cause mail loss if
208 you check your mail with other clients than fetchmail, and cause
209 fetchmail to delete a message it had never fetched before. It can also
210 cause mail loss if the mail server marks the message seen after
211 retrieval (IMAP2 servers). You should probably not use this option in your
212 configuration file. If you use it with POP3, you must use the 'uidl'
213 option. What you probably want is the default setting: if you don't
214 specify '\-k', then fetchmail will automatically delete messages after
218 POP3/IMAP only, since version 6.3.0. Delete oversized messages from the
219 mailserver before retrieving new messages. The size limit should be
220 separately specified with the \-\-limit option. This option does not
221 work with ETRN or ODMR.
222 .SS Protocol and Query Options
224 .B \-p <proto> | \-\-proto <proto> | \-\-protocol <proto>
225 (Keyword: proto[col])
226 Specify the protocol to use when communicating with the remote
227 mailserver. If no protocol is specified, the default is AUTO.
229 may be one of the following:
232 Tries IMAP, POP3, and POP2 (skipping any of these for which support
233 has not been compiled in).
235 Post Office Protocol 2 (legacy, to be removed from future release)
237 Post Office Protocol 3
239 Use POP3 with old-fashioned MD5-challenge authentication.
241 Use POP3 with RPOP authentication.
243 Use POP3 with Kerberos V4 authentication on port 1109.
245 Use POP3 with Demon Internet's SDPS extensions.
247 IMAP2bis, IMAP4, or IMAP4rev1 (\fIfetchmail\fR automatically detects their capabilities).
249 Use the ESMTP ETRN option.
251 Use the the On-Demand Mail Relay ESMTP profile.
254 All these alternatives work in basically the same way (communicating
255 with standard server daemons to fetch mail already delivered to a
256 mailbox on the server) except ETRN and ODMR. The ETRN mode
257 allows you to ask a compliant ESMTP server (such as BSD sendmail at
258 release 8.8.0 or higher) to immediately open a sender-SMTP connection
259 to your client machine and begin forwarding any items addressed to
260 your client machine in the server's queue of undelivered mail. The
261 ODMR mode requires an ODMR-capable server and works similarly to
262 ETRN, except that it does not require the client machine to have
267 Force UIDL use (effective only with POP3). Force client-side tracking
268 of 'newness' of messages (UIDL stands for "unique ID listing" and is
269 described in RFC1939). Use with 'keep' to use a mailbox as a baby
270 news drop for a group of users. The fact that seen messages are skipped
271 is logged, unless error logging is done through syslog while running in
272 daemon mode. Note that fetchmail may automatically enable this option
273 depending on upstream server capabilities. Note also that this option
274 may be removed and forced enabled in a future fetchmail version. See
277 .B \-\-idle (since 6.3.3)
278 (Keyword: idle, since before 6.0.0)
279 Enable IDLE use (effective only with IMAP). Note that this works with
280 only one folder at a given time. While the idle rcfile keyword had been
281 supported for a long time, the \-\-idle command-line option was added in
282 version 6.3.3. IDLE use means that fetchmail tells the IMAP server to
283 send notice of new messages, so they can be retrieved sooner than would
284 be possible with regular polls.
286 .B \-P <portnumber> | \-\-service <servicename>
287 (Keyword: service) Since version 6.3.0.
288 The service option permits you to specify a service name to connect to.
289 You can specify a decimal port number here, if your services database
290 lacks the required service-port assignments. See the FAQ item R12 and
291 the \-\-ssl documentation for details. This replaces the older \-\-port
294 .B \-\-port <portnumber>
296 Obsolete version of \-\-service that does not take service names.
298 this option may be removed from a future version.
300 .B \-\-principal <principal>
302 The principal option permits you to specify a service principal for
303 mutual authentication. This is applicable to POP3 or IMAP with Kerberos
306 .B \-t <seconds> | \-\-timeout <seconds>
308 The timeout option allows you to set a server-nonresponse
309 timeout in seconds. If a mailserver does not send a greeting message
310 or respond to commands for the given number of seconds,
311 \fIfetchmail\fR will hang up on it. Without such a timeout
312 \fIfetchmail\fR might hang up indefinitely trying to fetch mail from a
313 down host. This would be particularly annoying for a \fIfetchmail\fR
314 running in background. There is a default timeout which fetchmail\~\-V
315 will report. If a given connection receives too many timeouts in
316 succession, fetchmail will consider it wedged and stop retrying,
317 the calling user will be notified by email if this happens.
319 .B \-\-plugin <command>
320 (Keyword: plugin) The plugin option allows you to use an external
321 program to establish the TCP connection. This is useful if you want
322 to use socks, SSL, ssh, or need some special firewalling setup. The
323 program will be looked up in $PATH and can optionally be passed the
324 hostname and port as arguments using "%h" and "%p" respectively (note
325 that the interpolation logic is rather primitive, and these token must
326 be bounded by whitespace or beginning of string or end of string).
327 Fetchmail will write to the plugin's stdin and read from the plugin's
330 .B \-\-plugout <command>
332 Identical to the plugin option above, but this one is used for the SMTP
333 connections (which will probably not need it, so it has been separated
336 .B \-r <name> | \-\-folder <name>
338 Causes a specified non-default mail folder on the mailserver (or
339 comma-separated list of folders) to be retrieved. The syntax of the
340 folder name is server-dependent. This option is not available under
344 (Keyword: tracepolls)
345 Tell fetchmail to poll trace information in the form 'polling %s
346 account %s' and 'folder %s' to the Received line it generates,
347 where the %s parts are replaced by the user's remote name, the poll
348 label, and the folder (mailbox) where available (the Received header
349 also normally includes the server's true name). This can be used to
350 facilitate mail filtering based on the account it is being received
351 from. The folder information is written only since version 6.3.4.
355 Causes the connection to the mail server to be encrypted via SSL. Connect
356 to the server using the specified base protocol over a connection secured
357 by SSL. This option defeats TLS negotiation. Use \-\-sslcertck to
358 validate the certificates presented by the server.
360 Note that fetchmail may still try to negotiate TLS even if this option
361 is not given. You can use the \-\-sslproto option to defeat this
362 behavior or tell fetchmail to negotiate a particular SSL protocol.
364 If no port is specified, the connection is attempted to the well known
365 port of the SSL version of the base protocol. This is generally a
366 different port than the port used by the base protocol. For IMAP, this
367 is port 143 for the clear protocol and port 993 for the SSL secured
368 protocol, for POP3, it is port 110 for the clear text and port 995 for
369 the encrypted variant.
371 If your system lacks the corresponding entries from /etc/services, see
372 the \-\-service option and specify the numeric port number as given in
373 the previous paragraph (unless your ISP had directed you to different
374 ports, which is uncommon however).
376 .B \-\-sslcert <name>
378 Specifies the file name of the client side public SSL certificate. Some
379 SSL encrypted servers may require client side keys and certificates for
380 authentication. In most cases, this is optional. This specifies
381 the location of the public key certificate to be presented to the server
382 at the time the SSL session is established. It is not required (but may
383 be provided) if the server does not require it. Some servers may
384 require it, some servers may request it but not require it, and some
385 servers may not request it at all. It may be the same file
386 as the private key (combined key and certificate file) but this is not
390 If you use client authentication, the user name is fetched from the
391 certificate's CommonName and overrides the name set with \-\-user.
395 Specifies the file name of the client side private SSL key. Some SSL
396 encrypted servers may require client side keys and certificates for
397 authentication. In most cases, this is optional. This specifies
398 the location of the private key used to sign transactions with the server
399 at the time the SSL session is established. It is not required (but may
400 be provided) if the server does not require it. Some servers may
401 require it, some servers may request it but not require it, and some
402 servers may not request it at all. It may be the same file
403 as the public key (combined key and certificate file) but this is not
404 recommended. If a password is required to unlock the key, it will be
405 prompted for at the time just prior to establishing the session to the
406 server. This can cause some complications in daemon mode.
408 .B \-\-sslproto <name>
410 Forces an SSL or TLS protocol. Possible values are '\fBSSL2\fR',
411 \&'\fBSSL3\fR', '\fBSSL23\fR', and '\fBTLS1\fR'. Try this if the default
412 handshake does not work for your server. Use this option with
413 '\fBTLS1\fR' to enforce a TLS connection. To defeat opportunistic TLSv1
414 negotiation when the server advertises STARTTLS or STLS, use \fB''\fR.
415 This option, even if the argument is the empty string, will also
416 suppress the diagnostic 'SERVER: opportunistic upgrade to TLS.' message
417 in verbose mode. The default is to try appropriate protocols depending
422 Causes fetchmail to strictly check the server certificate against a set of
423 local trusted certificates (see the \fBsslcertpath\fR option). If the server
424 certificate cannot be obtained or is not signed by one of the trusted ones
425 (directly or indirectly), the SSL connection will fail, regardless of
426 the \fBsslfingerprint\fR option.
427 Note that CRL are only supported in OpenSSL 0.9.7 and newer! Your system
428 clock should also be reasonably accurate when using this option.
430 Note that this optional behavior may become default behavior in future
433 .B \-\-sslcertpath <directory>
434 (Keyword: sslcertpath)
435 Sets the directory fetchmail uses to look up local certificates. The default
436 is your OpenSSL default one. The directory must be hashed as OpenSSL expects
437 it - every time you add or modify a certificate in the directory, you need
438 to use the \fBc_rehash\fR tool (which comes with OpenSSL in the tools/
441 .B \-\-sslfingerprint <fingerprint>
442 (Keyword: sslfingerprint)
443 Specify the fingerprint of the server key (an MD5 hash of the key) in
444 hexadecimal notation with colons separating groups of two digits. The letter
445 hex digits must be in upper case. This is the default format OpenSSL uses,
446 and the one fetchmail uses to report the fingerprint when an SSL connection
447 is established. When this is specified, fetchmail will compare the server key
448 fingerprint with the given one, and the connection will fail if they do not
449 match regardless of the \fBsslcertck\fR setting. The connection will
450 also fail if fetchmail cannot obtain an SSL certificate from the server.
451 This can be used to prevent man-in-the-middle attacks, but the finger
452 print from the server needs to be obtained or verified over a secure
453 channel, and certainly not over the same Internet connection that
456 Using this option will prevent printing certificate verification errors
457 as long as \-\-sslcertck is unset.
459 To obtain the fingerprint of a certificate stored in the file cert.pem,
463 openssl x509 \-in cert.pem \-noout \-md5 \-fingerprint
468 .SS Delivery Control Options
470 .B \-S <hosts> | \-\-smtphost <hosts>
471 (Keyword: smtp[host])
472 Specify a hunt list of hosts to forward mail to (one or more
473 hostnames, comma-separated). Hosts are tried in list order; the first
474 one that is up becomes the forwarding target for the current run. If
475 this option is not specified, 'localhost' is used as the default.
476 Each hostname may have a port number following the host name. The
477 port number is separated from the host name by a slash; the default
478 port is "smtp". If you specify an absolute path name (beginning with
479 a /), it will be interpreted as the name of a UNIX socket accepting
480 LMTP connections (such as is supported by the Cyrus IMAP daemon)
484 \-\-smtphost server1,server2/2525,server3,/var/imap/socket/lmtp
487 This option can be used with ODMR, and will make fetchmail a relay
488 between the ODMR server and SMTP or LMTP receiver.
490 .B \-\-fetchdomains <hosts>
491 (Keyword: fetchdomains)
492 In ETRN or ODMR mode, this option specifies the list of domains the
493 server should ship mail for once the connection is turned around. The
494 default is the FQDN of the machine running
497 .B \-D <domain> | \-\-smtpaddress <domain>
498 (Keyword: smtpaddress) Specify the domain to be appended to addresses
499 in RCPT TO lines shipped to SMTP. When this is not specified, the name
500 of the SMTP server (as specified by \-\-smtphost) is used for SMTP/LMTP
501 and 'localhost' is used for UNIX socket/BSMTP.
503 .B \-\-smtpname <user@domain>
505 Specify the domain and user to be put in RCPT TO lines shipped to SMTP.
506 The default user is the current local user.
508 .B \-Z <nnn> | \-\-antispam <nnn[, nnn]...>
510 Specifies the list of numeric SMTP errors that are to be interpreted
511 as a spam-block response from the listener. A value of \-1 disables
512 this option. For the command-line option, the list values should
515 .B \-m <command> | \-\-mda <command>
516 (Keyword: mda) You can force mail to be passed to an MDA directly
517 (rather than forwarded to port 25) with the \-\-mda or \-m option. To
518 avoid losing mail, use this option only with MDAs like maildrop or
519 MTAs like sendmail that return a nonzero status on disk-full and other
520 resource-exhaustion errors; the nonzero status tells fetchmail that
521 delivery failed and prevents the message from being deleted off the
522 server. If \fIfetchmail\fR is running as root, it sets its user id to
523 that of the target user while delivering mail through an MDA. Some
524 possible MDAs are "/usr/sbin/sendmail \-i \-f %F \-\- %T" (\fBNote:\fR
525 some several older or vendor sendmail versions mistake \-\- for an
526 address, rather than an indicator to mark the end of the option arguments),
527 "/usr/bin/deliver" and "/usr/bin/maildrop \-d %T". Local delivery
528 addresses will be inserted into the MDA command wherever you place a
529 %T; the mail message's From address will be inserted where you place
530 an %F. \fBDO NOT ENCLOSE THE %F OR %T STRING IN SINGLE QUOTES!\fR For
531 both %T and %F, fetchmail encloses the addresses in single quotes ('),
532 after removing any single quotes they may contain, before the MDA
533 command is passed to the shell. Do \fINOT\fR use an MDA invocation
534 like "sendmail \-i \-t" that dispatches on the contents of To/Cc/Bcc, it
535 will create mail loops and bring the just wrath of many postmasters
536 down upon your head. Also, do \fInot\fR try to combine multidrop
537 mode with an MDA such as maildrop that can only accept one
538 address; you will lose mail.
540 A word of warning: the well-known
542 package is very hard to configure properly, it has a very nasty "fall
543 through to the next rule" behavior on delivery errors (even temporary
544 ones, such as out of disk space if another user's mail daemon copies the
545 mailbox around to purge old messages), so your mail will end up in the
546 wrong mailbox sooner or later. The proper procmail configuration is
547 outside the scope of this document though. Using
549 is usually much easier, and many users find the filter syntax used by
550 maildrop easier to understand.
555 Cause delivery via LMTP (Local Mail Transfer Protocol). A service
556 host and port \fBmust\fR be explicitly specified on each host in the
557 smtphost hunt list (see above) if this option is selected; the default
558 port 25 will (in accordance with RFC 2033) not be accepted.
560 .B \-\-bsmtp <filename>
562 Append fetched mail to a BSMTP file. This simply contains the SMTP
563 commands that would normally be generated by fetchmail when passing
564 mail to an SMTP listener daemon. An argument of '\-' causes the mail
565 to be written to standard output. Note that fetchmail's
566 reconstruction of MAIL FROM and RCPT TO lines is not guaranteed
567 correct; the caveats discussed under THE USE AND ABUSE OF MULTIDROP
568 MAILBOXES below apply.
569 .SS Resource Limit Control Options
571 .B \-l <maxbytes> | \-\-limit <maxbytes>
572 (Keyword: limit) Takes a maximum octet size argument. Messages larger
573 than this size will not be fetched and will be left on the server (in
574 foreground sessions, the progress messages will note that they are
575 "oversized"). If the fetch protocol permits (in particular, under
576 IMAP or POP3 without the fetchall option) the message will not be
579 An explicit \-\-limit of 0 overrides any limits set in your
580 run control file. This option is intended for those needing to
581 strictly control fetch time due to expensive and variable phone rates.
583 Combined with \-\-limitflush, it can be used to delete oversized
584 messages waiting on a server. In daemon mode, oversize notifications
585 are mailed to the calling user (see the \-\-warnings option). This
586 option does not work with ETRN or ODMR.
588 .B \-w <interval> | \-\-warnings <interval>
590 Takes an interval in seconds. When you call
592 with a 'limit' option in daemon mode, this controls the interval at
593 which warnings about oversized messages are mailed to the calling user
594 (or the user specified by the 'postmaster' option). One such
595 notification is always mailed at the end of the the first poll that
596 the oversized message is detected. Thereafter, re-notification is
597 suppressed until after the warning interval elapses (it will take
598 place at the end of the first following poll).
600 .B \-b <count> | \-\-batchlimit <count>
601 (Keyword: batchlimit)
602 Specify the maximum number of messages that will be shipped to an SMTP
603 listener before the connection is deliberately torn down and rebuilt
604 (defaults to 0, meaning no limit). An explicit \-\-batchlimit of 0
605 overrides any limits set in your run control file. While
606 \fBsendmail\fR(8) normally initiates delivery of a message immediately
607 after receiving the message terminator, some SMTP listeners are not so
608 prompt. MTAs like \fIsmail\fR(8) may wait till the
609 delivery socket is shut down to deliver. This may produce annoying
610 delays when \fIfetchmail\fR is processing very large batches. Setting
611 the batch limit to some nonzero size will prevent these delays. This
612 option does not work with ETRN or ODMR.
614 .B \-B <number> | \-\-fetchlimit <number>
615 (Keyword: fetchlimit)
616 Limit the number of messages accepted from a given server in a single
617 poll. By default there is no limit. An explicit \-\-fetchlimit of 0
618 overrides any limits set in your run control file.
619 This option does not work with ETRN or ODMR.
621 .B \-\-fetchsizelimit <number>
622 (Keyword: fetchsizelimit)
623 Limit the number of sizes of messages accepted from a given server in
624 a single transaction. This option is useful in reducing the delay in
625 downloading the first mail when there are too many mails in the
626 mailbox. By default, the limit is 100. If set to 0, sizes of all
627 messages are downloaded at the start.
628 This option does not work with ETRN or ODMR. For POP3, the only valid
631 .B \-\-fastuidl <number>
633 Do a binary instead of linear search for the first unseen UID. Binary
634 search avoids downloading the UIDs of all mails. This saves time
635 (especially in daemon mode) where downloading the same set of UIDs in
636 each poll is a waste of bandwidth. The number 'n' indicates how rarely
637 a linear search should be done. In daemon mode, linear search is used
638 once followed by binary searches in 'n-1' polls if 'n' is greater than
639 1; binary search is always used if 'n' is 1; linear search is always
640 used if 'n' is 0. In non-daemon mode, binary search is used if 'n' is
641 1; otherwise linear search is used. The default value of 'n' is 4.
642 This option works with POP3 only.
644 .B \-e <count> | \-\-expunge <count>
646 Arrange for deletions to be made final after a given number of
647 messages. Under POP2 or POP3, fetchmail cannot make deletions final
648 without sending QUIT and ending the session -- with this option on,
649 fetchmail will break a long mail retrieval session into multiple
650 sub-sessions, sending QUIT after each sub-session. This is a good
651 defense against line drops on POP3 servers. Under IMAP,
653 normally issues an EXPUNGE command after each deletion in order to
654 force the deletion to be done immediately. This is safest when your
655 connection to the server is flaky and expensive, as it avoids
656 resending duplicate mail after a line hit. However, on large
657 mailboxes the overhead of re-indexing after every message can slam the
658 server pretty hard, so if your connection is reliable it is good to do
659 expunges less frequently. Also note that some servers enforce a delay
660 of a few seconds after each quit, so fetchmail may not be able to get
661 back in immediately after an expunge -- you may see "lock busy" errors
662 if this happens. If you specify this option to an integer N,
665 to only issue expunges on every Nth delete. An argument of zero
666 suppresses expunges entirely (so no expunges at all will be done until
667 the end of run). This option does not work with ETRN or ODMR.
668 .SS Authentication Options
670 .B \-u <name> | \-\-user <name> | \-\-username <name>
671 (Keyword: user[name])
672 Specifies the user identification to be used when logging in to the mailserver.
673 The appropriate user identification is both server and user-dependent.
674 The default is your login name on the client machine that is running
676 See USER AUTHENTICATION below for a complete description.
678 .B \-I <specification> | \-\-interface <specification>
680 Require that a specific interface device be up and have a specific local
681 or remote IPv4 (IPv6 is not supported by this option yet) address (or
682 range) before polling. Frequently \fIfetchmail\fP
683 is used over a transient point-to-point TCP/IP link established directly
684 to a mailserver via SLIP or PPP. That is a relatively secure channel.
685 But when other TCP/IP routes to the mailserver exist (e.g. when the link
686 is connected to an alternate ISP), your username and password may be
687 vulnerable to snooping (especially when daemon mode automatically polls
688 for mail, shipping a clear password over the net at predictable
689 intervals). The \-\-interface option may be used to prevent this. When
690 the specified link is not up or is not connected to a matching IP
691 address, polling will be skipped. The format is:
694 interface/iii.iii.iii.iii[/mmm.mmm.mmm.mmm]
697 The field before the first slash is the interface name (i.e. sl0, ppp0
698 etc.). The field before the second slash is the acceptable IP address.
699 The field after the second slash is a mask which specifies a range of
700 IP addresses to accept. If no mask is present 255.255.255.255 is
701 assumed (i.e. an exact match). This option is currently only supported
702 under Linux and FreeBSD. Please see the
704 section for below for FreeBSD specific information.
706 Note that this option may be removed from a future fetchmail version.
708 .B \-M <interface> | \-\-monitor <interface>
710 Daemon mode can cause transient links which are automatically taken down
711 after a period of inactivity (e.g. PPP links) to remain up
712 indefinitely. This option identifies a system TCP/IP interface to be
713 monitored for activity. After each poll interval, if the link is up but
714 no other activity has occurred on the link, then the poll will be
715 skipped. However, when fetchmail is woken up by a signal, the
716 monitor check is skipped and the poll goes through unconditionally.
717 This option is currently only supported under Linux and FreeBSD.
722 options to work for non root users under FreeBSD, the fetchmail binary
723 must be installed SGID kmem. This would be a security hole, but
724 fetchmail runs with the effective GID set to that of the kmem group
726 when interface data is being collected.
728 Note that this option may be removed from a future fetchmail version.
731 (Keyword: auth[enticate])
732 This option permits you to specify an authentication type (see USER
733 AUTHENTICATION below for details). The possible values are \fBany\fR,
734 \&\fBpassword\fR, \fBkerberos_v5\fR, \fBkerberos\fR (or, for
735 excruciating exactness, \fBkerberos_v4\fR), \fBgssapi\fR,
736 \fBcram\-md5\fR, \fBotp\fR, \fBntlm\fR, \fBmsn\fR (only for POP3),
737 \fBexternal\fR (only IMAP) and \fBssh\fR.
738 When \fBany\fR (the default) is specified, fetchmail tries
739 first methods that don't require a password (EXTERNAL, GSSAPI, KERBEROS\ IV,
740 KERBEROS\ 5); then it looks for methods that mask your password
741 (CRAM-MD5, X\-OTP - note that NTLM and MSN are not autoprobed for POP3
742 and MSN is only supported for POP3); and only if the server doesn't
743 support any of those will it ship your password en clair. Other values
744 may be used to force various authentication methods
745 (\fBssh\fR suppresses authentication and is thus useful for IMAP PREAUTH).
746 (\fBexternal\fR suppresses authentication and is thus useful for IMAP EXTERNAL).
747 Any value other than \fBpassword\fR, \fBcram\-md5\fR, \fBntlm\fR,
748 \&\fBmsn\fR or \fBotp\fR suppresses fetchmail's normal inquiry for a
749 password. Specify \fBssh\fR when you are using an end-to-end secure
750 connection such as an ssh tunnel; specify \fBexternal\fR when you use
751 TLS with client authentication and specify \fBgssapi\fR or
752 \&\fBkerberos_v4\fR if you are using a protocol variant that employs
753 GSSAPI or K4. Choosing KPOP protocol automatically selects Kerberos
754 authentication. This option does not work with ETRN.
755 .SS Miscellaneous Options
757 .B \-f <pathname> | \-\-fetchmailrc <pathname>
758 Specify a non-default name for the
760 run control file. The pathname argument must be either "-" (a single
761 dash, meaning to read the configuration from standard input) or a
762 filename. Unless the \-\-version option is also on, a named file
763 argument must have permissions no more open than 0600 (u=rw,g=,o=) or
766 .B \-i <pathname> | \-\-idfile <pathname>
768 Specify an alternate name for the .fetchids file used to save POP3
769 UIDs. NOTE: since fetchmail 6.3.0, write access to the directory
770 containing the idfile is required, as fetchmail writes a temporary file
771 and renames it into the place of the real idfile only if the temporary
772 file has been written successfully. This avoids the truncation of
773 idfiles when running out of disk space.
775 .B \--pidfile <pathname>
776 (Keyword: pidfile; since fetchmail v6.3.4)
777 Override the default location of the PID file. Default: see
780 .B \-n | \-\-norewrite
781 (Keyword: no rewrite)
784 edits RFC-822 address headers (To, From, Cc, Bcc, and Reply\-To) in
785 fetched mail so that any mail IDs local to the server are expanded to
786 full addresses (@ and the mailserver hostname are appended). This enables
787 replies on the client to get addressed correctly (otherwise your
788 mailer might think they should be addressed to local users on the
789 client machine!). This option disables the rewrite. (This option is
790 provided to pacify people who are paranoid about having an MTA edit
791 mail headers and want to know they can prevent it, but it is generally
792 not a good idea to actually turn off rewrite.)
793 When using ETRN or ODMR, the rewrite option is ineffective.
795 .B \-E <line> | \-\-envelope <line>
796 (Keyword: envelope; Multidrop only)
798 In the configuration file, an enhanced syntax is used:
800 .B envelope [<count>] <line>
802 This option changes the header
804 assumes will carry a copy of the mail's envelope address. Normally
805 this is 'X\-Envelope\-To', but as this header is not standard, practice
806 varies. See the discussion of multidrop address handling below. As a
807 special case, 'envelope "Received"' enables parsing of sendmail-style
808 Received lines. This is the default, and it should not be necessary
809 unless you have globally disabled Received parsing with 'no envelope'
810 in the \fI.fetchmailrc\fR file.
812 The optional count argument (only available in the configuration file)
813 determines how many header lines of this kind are skipped. A count of 1
814 means: skip the first, take the second. A count of 2 means: skip the
815 first and second, take the third, and so on.
817 .B \-Q <prefix> | \-\-qvirtual <prefix>
818 (Keyword: qvirtual; Multidrop only)
819 The string prefix assigned to this option will be removed from the user
820 name found in the header specified with the \fIenvelope\fR option
821 (\fIbefore\fR doing multidrop name mapping or localdomain checking,
822 if either is applicable). This option is useful if you are using
824 to collect the mail for an entire domain and your ISP (or your mail
825 redirection provider) is using qmail.
826 One of the basic features of qmail is the
830 message header. Whenever qmail delivers a message to a local mailbox
831 it puts the username and hostname of the envelope recipient on this
832 line. The major reason for this is to prevent mail loops. To set up
833 qmail to batch mail for a disconnected site the ISP-mailhost will have
834 normally put that site in its 'Virtualhosts' control file so it will
835 add a prefix to all mail addresses for this site. This results in mail
836 .\" The \&@\& tries to stop HTML converters from making a mailto URL here.
837 sent to 'username\&@\&userhost.userdom.dom.com' having a
838 \&'Delivered\-To:' line of the form:
840 Delivered\-To: mbox\-userstr\-username\&@\&userhost.example.com
842 The ISP can make the 'mbox\-userstr\-' prefix anything they choose
843 but a string matching the user host name is likely.
844 By using the option 'envelope Delivered\-To:' you can make fetchmail reliably
845 identify the original envelope recipient, but you have to strip the
846 \&'mbox\-userstr\-' prefix to deliver to the correct user.
847 This is what this option is for.
852 file, interpret any command-line options specified, and dump a
853 configuration report to standard output. The configuration report is
854 a data structure assignment in the language Python. This option
855 is meant to be used with an interactive
863 Removed before version 6.3.0, the required underlying inet6_apps library
864 had been discontinued and is no longer available.
866 .SH USER AUTHENTICATION AND ENCRYPTION
867 All modes except ETRN require authentication of the client to the server.
868 Normal user authentication in
870 is very much like the authentication mechanism of
872 The correct user-id and password depend upon the underlying security
873 system at the mailserver.
875 If the mailserver is a Unix machine on which you have an ordinary user
876 account, your regular login name and password are used with
878 If you use the same login name on both the server and the client machines,
879 you needn't worry about specifying a user-id with the
881 option -- the default behavior is to use your login name on the
882 client machine as the user-id on the server machine. If you use a
883 different login name on the server machine, specify that login name
886 option. e.g. if your login name is 'jsmith' on a machine named 'mailgrunt',
891 fetchmail \-u jsmith mailgrunt
893 The default behavior of
895 is to prompt you for your mailserver password before the connection is
896 established. This is the safest way to use
898 and ensures that your password will not be compromised. You may also specify
899 your password in your
901 file. This is convenient when using
903 in daemon mode or with scripts.
904 .SS Using netrc files
906 If you do not specify a password, and
908 cannot extract one from your
910 file, it will look for a
912 file in your home directory before requesting one interactively; if an
913 entry matching the mailserver is found in that file, the password will
914 be used. Fetchmail first looks for a match on poll name; if it finds none,
915 it checks for a match on via name. See the
917 man page for details of the syntax of the
919 file. To show a practical example, a .netrc might look like
923 machine hermes.example.org
928 You can repeat this block with different user information if you need to
929 provide more than one password.
931 This feature may allow you to avoid duplicating password
932 information in more than one file.
934 On mailservers that do not provide ordinary user accounts, your user-id and
935 password are usually assigned by the server administrator when you apply for
936 a mailbox on the server. Contact your server administrator if you don't know
937 the correct user-id and password for your mailbox account.
940 Early versions of POP3 (RFC1081, RFC1225) supported a crude form of
941 independent authentication using the
943 file on the mailserver side. Under this RPOP variant, a fixed
944 per-user ID equivalent to a password was sent in clear over a link to
945 a reserved port, with the command RPOP rather than PASS to alert the
946 server that it should do special checking. RPOP is supported
949 (you can specify 'protocol RPOP' to have the program send 'RPOP'
950 rather than 'PASS') but its use is strongly discouraged, and support
951 will be removed from a future fetchmail version. This
952 facility was vulnerable to spoofing and was withdrawn in RFC1460.
954 RFC1460 introduced APOP authentication. In this variant of POP3,
955 you register an APOP password on your server host (the program
956 to do this with on the server is probably called \fIpopauth\fR(8)). You
957 put the same password in your
961 logs in, it sends a cryptographically secure hash of your password and
962 the server greeting time to the server, which can verify it by
963 checking its authorization database.
966 makes some efforts to make the server believe messages had not been
967 retrieved, by using the TOP command with a large number of lines when
968 possible. TOP is a command that retrieves the full header and
969 a \fIfetchmail\fP-specified amount of body lines. It is optional and
970 therefore not implemented by all servers, and some are known to
971 implement it improperly. On many servers however, the RETR command which
972 retrieves the full message with header and body, sets the "seen" flag
973 (for instance, in a web interface), whereas the TOP command does not do
977 will always use the RETR command if "fetchall" is set.
979 will also use the RETR command if "keep" is set and "uidl" is unset.
982 will use the RETR command on Maillennium POP3/PROXY
983 servers (used by Comcast) to avoid a deliberate TOP misinterpretation in
984 this server that causes message corruption.
988 will use the TOP command. This implies that in "keep" setups, "uidl"
989 must be set if "TOP" is desired.
992 that this description is true for the current version of fetchmail, but
993 the behavior may change in future versions. In particular, fetchmail may
994 prefer the RETR command because the TOP command causes much grief on
995 some servers and is only optional.
996 .SH ALTERNATE AUTHENTICATION FORMS
998 If your \fIfetchmail\fR was built with Kerberos support and you specify
999 Kerberos authentication (either with \-\-auth or the \fI.fetchmailrc\fR
1000 option \fBauthenticate kerberos_v4\fR) it will try to get a Kerberos
1001 ticket from the mailserver at the start of each query. Note: if
1002 either the pollname or via name is 'hesiod', fetchmail will try to use
1003 Hesiod to look up the mailserver.
1005 If you use POP3 or IMAP with GSSAPI authentication, \fIfetchmail\fR will
1006 expect the server to have RFC1731- or RFC1734-conforming GSSAPI
1007 capability, and will use it. Currently this has only been tested over
1008 Kerberos V, so you're expected to already have a ticket-granting
1009 ticket. You may pass a username different from your principal name
1010 using the standard \fB\-\-user\fR command or by the \fI.fetchmailrc\fR
1013 If your IMAP daemon returns the PREAUTH response in its greeting line,
1014 fetchmail will notice this and skip the normal authentication step.
1015 This can be useful, e.g. if you start imapd explicitly using ssh.
1016 In this case you can declare the authentication value 'ssh' on that
1017 site entry to stop \fI.fetchmail\fR from asking you for a password
1020 If you use client authentication with \fITLS1\fR and your IMAP daemon
1021 returns the \fIAUTH=EXTERNAL\fR response, fetchmail will notice this
1022 and will use the authentication shortcut and will not send the
1023 passphrase. In this case you can declare the authentication value 'external'
1024 on that site to stop \fIfetchmail\fR from asking you for a password
1027 If you are using POP3, and the server issues a one-time-password
1028 challenge conforming to RFC1938, \fIfetchmail\fR will use your
1029 password as a pass phrase to generate the required response. This
1030 avoids sending secrets over the net unencrypted.
1032 Compuserve's RPA authentication (similar to APOP) is supported. If you
1033 compile in the support, \fIfetchmail\fR will try to perform an RPA pass-phrase
1034 authentication instead of sending over the password en clair if it
1035 detects "@compuserve.com" in the hostname.
1037 If you are using IMAP, Microsoft's NTLM authentication (used by Microsoft
1038 Exchange) is supported. If you compile in the support, \fIfetchmail\fR
1039 will try to perform an NTLM authentication (instead of sending over the
1040 password en clair) whenever the server returns AUTH=NTLM in its
1041 capability response. Specify a user option value that looks like
1042 \&'user@domain': the part to the left of the @ will be passed as the
1043 username and the part to the right as the NTLM domain.
1044 .SS Secure Socket Layers (SSL) and Transport Layer Security (TLS)
1046 You can access SSL encrypted services by specifying the \-\-ssl option.
1047 You can also do this using the "ssl" user option in the .fetchmailrc
1048 file. With SSL encryption enabled, queries are initiated over a connection
1049 after negotiating an SSL session, and the connection fails if SSL cannot
1050 be negotiated. Some services, such as POP3 and IMAP, have different
1051 well known ports defined for the SSL encrypted services. The encrypted
1052 ports will be selected automatically when SSL is enabled and no explicit
1053 port is specified. The \-\-sslproto option can be used to select the SSL
1054 protocols (default: v2 or v3). The \-\-sslcertck command line or
1055 sslcertck run control file option should be used to force strict
1056 certificate checking - see below.
1058 If SSL is not configured, fetchmail will usually opportunistically try to use
1059 TLS. TLS can be enforced by using \-\-sslproto "TLS1". TLS
1060 connections use the same port as the unencrypted version of the
1061 protocol and negotiate TLS via special parameter. The \-\-sslcertck
1062 command line or sslcertck run control file option should be used to
1063 force strict certificate checking - see below.
1065 .B \-\-sslcheck recommended:
1066 When connecting to an SSL or TLS encrypted server, the server presents a certificate
1067 to the client for validation. The certificate is checked to verify that
1068 the common name in the certificate matches the name of the server being
1069 contacted and that the effective and expiration dates in the certificate
1070 indicate that it is currently valid. If any of these checks fail, a warning
1071 message is printed, but the connection continues. The server certificate
1072 does not need to be signed by any specific Certifying Authority and may
1073 be a "self-signed" certificate. If the \-\-sslcertck command line option
1074 or sslcertck run control file option is used, fetchmail will instead
1075 abort if any of these checks fail. Use of the sslcertck or \-\-sslcertck
1078 Some SSL encrypted servers may request a client side certificate. A client
1079 side public SSL certificate and private SSL key may be specified. If
1080 requested by the server, the client certificate is sent to the server for
1081 validation. Some servers may require a valid client certificate and may
1082 refuse connections if a certificate is not provided or if the certificate
1083 is not valid. Some servers may require client side certificates be signed
1084 by a recognized Certifying Authority. The format for the key files and
1085 the certificate files is that required by the underlying SSL libraries
1086 (OpenSSL in the general case).
1088 A word of care about the use of SSL: While above mentioned
1089 setup with self-signed server certificates retrieved over the wires
1090 can protect you from a passive eavesdropper, it doesn't help against an
1091 active attacker. It's clearly an improvement over sending the
1092 passwords in clear, but you should be aware that a man-in-the-middle
1093 attack is trivially possible (in particular with tools such as dsniff,
1094 http://monkey.org/~dugsong/dsniff/). Use of strict certificate checking
1095 with a certification authority recognized by server and client, or
1096 perhaps of an SSH tunnel (see below for some examples) is preferable if
1097 you care seriously about the security of your mailbox and passwords.
1101 also supports authentication to the ESMTP server on the client side
1102 according to RFC 2554. You can specify a name/password pair to be
1103 used with the keywords 'esmtpname' and 'esmtppassword'; the former
1104 defaults to the username of the calling user.
1107 .SS Introducing the daemon mode
1110 puts itself into the background and runs forever, querying each
1111 specified host and then sleeping for a given polling interval.
1112 .SS Starting the daemon mode
1113 There are several ways to make fetchmail work in daemon mode. On the
1114 command line, \fB\-\-daemon\ <interval>\fR or \fB\-d\ <interval>\fR
1115 option runs \fIfetchmail\fR in daemon mode. You must specify a numeric
1116 argument which is a polling interval in seconds.
1118 Example: simply invoking
1122 will, therefore, poll all the hosts described in your
1124 file (except those explicitly excluded with the 'skip' verb) once
1127 It is also possible to set a polling interval
1128 in your \fI~/.fetchmailrc\fR file by saying 'set\ daemon\ <interval>',
1129 where <interval> is an integer number of seconds. If you do this,
1130 fetchmail will always start in daemon mode unless you override it with
1131 the command-line option \-\-daemon 0 or \-d0.
1133 Only one daemon process is permitted per user; in daemon mode,
1134 \fIfetchmail\fR sets up a per-user lockfile to guarantee this.
1135 (You can however cheat and set the FETCHMAILHOME environment variable to
1136 overcome this setting, but in that case, it is your responsibility to
1137 make sure you aren't polling the same server with two processes at the
1139 .SS Awakening the background daemon
1141 Normally, calling fetchmail with a daemon in the background sends a
1142 wake-up signal to the daemon and quits without output. The background
1143 daemon then starts its next poll cycle immediately. The wake-up signal,
1144 SIGUSR1, can also be sent manually. The wake-up action also clears any
1145 'wedged' flags indicating that connections have wedged due to failed
1146 authentication or multiple timeouts.
1147 .SS Terminating the background daemon
1151 will kill a running daemon process instead of waking it up (if there
1152 is no such process, \fIfetchmail\fP will notify you.
1153 If the \-\-quit option appears last on the command line, \fIfetchmail\fP
1154 will kill the running daemon process and then quit. Otherwise,
1155 \fIfetchmail\fP will first kill a running daemon process and then
1156 continue running with the other options.
1157 .SS Useful options for daemon mode
1162 .B \-\-logfile <filename>
1163 option (keyword: set logfile) is only effective when fetchmail is
1164 detached. This option allows you to redirect status messages
1165 into a specified logfile (follow the option with the logfile name). The
1166 logfile is opened for append, so previous messages aren't deleted. This
1167 is primarily useful for debugging configurations. Note that fetchmail
1168 does not detect if the logfile is rotated, the logfile is only opened
1169 once when fetchmail starts. You need to restart fetchmail after rotating
1170 the logfile and before compressing it (if applicable).
1174 option (keyword: set syslog) allows you to redirect status and error
1175 messages emitted to the
1177 system daemon if available.
1178 Messages are logged with an id of \fBfetchmail\fR, the facility \fBLOG_MAIL\fR,
1179 and priorities \fBLOG_ERR\fR, \fBLOG_ALERT\fR or \fBLOG_INFO\fR.
1180 This option is intended for logging status and error messages which
1181 indicate the status of the daemon and the results while fetching mail
1183 Error messages for command line options and parsing the \fI.fetchmailrc\fR
1184 file are still written to stderr, or to the specified log file.
1187 option turns off use of
1189 assuming it's turned on in the
1194 .B \-\-logfile <file>
1201 option suppresses backgrounding and detachment of the
1202 daemon process from its control terminal. This is useful
1203 for debugging or when fetchmail runs as the child of a supervisor
1208 Note that this also causes the logfile option to be
1209 ignored (though perhaps it shouldn't).
1211 Note that while running in daemon mode polling a POP2 or IMAP2bis server,
1212 transient errors (such as DNS failures or sendmail delivery refusals)
1213 may force the fetchall option on for the duration of the next polling
1214 cycle. This is a robustness feature. It means that if a message is
1215 fetched (and thus marked seen by the mailserver) but not delivered
1216 locally due to some transient error, it will be re-fetched during the
1217 next poll cycle. (The IMAP logic doesn't delete messages until
1218 they're delivered, so this problem does not arise.)
1220 If you touch or change the
1222 file while fetchmail is running in daemon mode, this will be detected
1223 at the beginning of the next poll cycle. When a changed
1225 is detected, fetchmail rereads it and restarts from scratch (using
1226 exec(2); no state information is retained in the new instance).
1227 Note also that if you break the
1229 file's syntax, the new instance will softly and silently vanish away
1232 .SH ADMINISTRATIVE OPTIONS
1235 .B \-\-postmaster <name>
1236 option (keyword: set postmaster) specifies the last-resort username to
1237 which multidrop mail is to be forwarded if no matching local recipient
1238 can be found. It is also used as destination of undeliverable mail if
1239 the 'bouncemail' global option is off and additionally for spam-blocked
1240 mail if the 'bouncemail' global option is off and the 'spambounce'
1241 global option is on. This option defaults to the user who invoked
1243 If the invoking user is root, then the default of this option is
1244 the user 'postmaster'. Setting postmaster to the empty string causes
1245 such mail as described above to be discarded - this however is usually a
1247 See also the description of the 'FETCHMAILUSER' environment variable in
1248 the ENVIRONMENT section below.
1252 behaves like the "set no bouncemail" global option, which see.
1256 option (keyword: set invisible) tries to make fetchmail invisible.
1257 Normally, fetchmail behaves like any other MTA would -- it generates a
1258 Received header into each message describing its place in the chain of
1259 transmission, and tells the MTA it forwards to that the mail came from
1260 the machine fetchmail itself is running on. If the invisible option
1261 is on, the Received header is suppressed and fetchmail tries to spoof
1262 the MTA it forwards to into thinking it came directly from the
1267 option (keyword: set showdots) forces fetchmail to show progress dots
1268 even if the current tty is not stdout (for example logfiles).
1269 Fetchmail shows the dots by default when run in nodetach mode or when
1270 daemon mode is not enabled.
1274 option, you can ask fetchmail to add information to the Received
1275 header on the form "polling {label} account {user}", where {label} is
1276 the account label (from the specified rcfile, normally ~/.fetchmailrc)
1277 and {user} is the username which is used to log on to the mail
1278 server. This header can be used to make filtering email where no
1279 useful header information is available and you want mail from
1280 different accounts sorted into different mailboxes (this could, for
1281 example, occur if you have an account on the same server running a
1282 mailing list, and are subscribed to the list using that account). The
1283 default is not adding any such header. In
1285 this is called 'tracepolls'.
1287 .SH RETRIEVAL FAILURE MODES
1288 The protocols \fIfetchmail\fR uses to talk to mailservers are next to
1289 bulletproof. In normal operation forwarding to port 25, no message is
1290 ever deleted (or even marked for deletion) on the host until the SMTP
1291 listener on the client side has acknowledged to \fIfetchmail\fR that
1292 the message has been either accepted for delivery or rejected due to a
1295 When forwarding to an MDA, however, there is more possibility
1296 of error. Some MDAs are 'safe' and reliably return a nonzero status
1297 on any delivery error, even one due to temporary resource limits.
1300 program is like this; so are most programs designed as mail transport
1303 including the sendmail wrapper of Postfix and
1305 These programs give back a reliable positive acknowledgement and
1306 can be used with the mda option with no risk of mail loss. Unsafe
1307 MDAs, though, may return 0 even on delivery failure. If this
1308 happens, you will lose mail.
1310 The normal mode of \fIfetchmail\fR is to try to download only 'new'
1311 messages, leaving untouched (and undeleted) messages you have already
1312 read directly on the server (or fetched with a previous \fIfetchmail
1313 \-\-keep\fR). But you may find that messages you've already read on the
1314 server are being fetched (and deleted) even when you don't specify
1315 \-\-all. There are several reasons this can happen.
1317 One could be that you're using POP2. The POP2 protocol includes no
1318 representation of 'new' or 'old' state in messages, so \fIfetchmail\fR
1319 must treat all messages as new all the time. But POP2 is obsolete, so
1322 A potential POP3 problem might be servers that insert messages
1323 in the middle of mailboxes (some VMS implementations of mail are
1324 rumored to do this). The \fIfetchmail\fR code assumes that new
1325 messages are appended to the end of the mailbox; when this is not true
1326 it may treat some old messages as new and vice versa. Using UIDL whilst
1327 setting fastuidl 0 might fix this, otherwise, consider switching to IMAP.
1329 Yet another POP3 problem is that if they can't make tempfiles in the
1330 user's home directory, some POP3 servers will hand back an
1331 undocumented response that causes fetchmail to spuriously report "No
1334 The IMAP code uses the presence or absence of the server flag \eSeen
1335 to decide whether or not a message is new. This isn't the right thing
1336 to do, fetchmail should check the UIDVALIDITY and use UID, but it
1337 doesn't do that yet. Under Unix, it counts on your IMAP server to notice
1338 the BSD-style Status flags set by mail user agents and set the \eSeen
1339 flag from them when appropriate. All Unix IMAP servers we know of do
1340 this, though it's not specified by the IMAP RFCs. If you ever trip over
1341 a server that doesn't, the symptom will be that messages you have
1342 already read on your host will look new to the server. In this
1343 (unlikely) case, only messages you fetched with \fIfetchmail \-\-keep\fR
1344 will be both undeleted and marked old.
1346 In ETRN and ODMR modes, \fIfetchmail\fR does not actually retrieve messages;
1347 instead, it asks the server's SMTP listener to start a queue flush
1348 to the client via SMTP. Therefore it sends only undelivered messages.
1351 Many SMTP listeners allow administrators to set up 'spam filters' that
1352 block unsolicited email from specified domains. A MAIL FROM or DATA line that
1353 triggers this feature will elicit an SMTP response which
1354 (unfortunately) varies according to the listener.
1358 return an error code of 571.
1360 According to RFC2821, the correct thing to return in this situation is
1361 550 "Requested action not taken: mailbox unavailable" (the draft adds
1362 "[E.g., mailbox not found, no access, or command rejected for policy
1365 Older versions of the
1367 MTA return 501 "Syntax error in parameters or arguments".
1371 MTA runs 554 as an antispam response.
1374 may reject code with a 500 response (followed by an enhanced status
1375 code that contains more information).
1379 treats as antispam responses and discards
1380 the message can be set with the 'antispam' option. This is one of the
1382 three circumstance under which fetchmail ever discards mail (the others
1383 are the 552 and 553 errors described below, and the suppression of
1384 multidropped messages with a message-ID already seen).
1388 is fetching from an IMAP server, the antispam response will be detected and
1389 the message rejected immediately after the headers have been fetched,
1390 without reading the message body. Thus, you won't pay for downloading
1391 spam message bodies.
1393 By default, the list of antispam responses is empty.
1395 If the \fIspambounce\fR global option is on, mail that is spam-blocked
1396 triggers an RFC1892/RFC1894 bounce message informing the originator that
1397 we do not accept mail from it. See also BUGS.
1399 .SH SMTP/ESMTP ERROR HANDLING
1400 Besides the spam-blocking described above, fetchmail takes special
1401 actions on the following SMTP/ESMTP error responses
1403 452 (insufficient system storage)
1404 Leave the message in the server mailbox for later retrieval.
1406 552 (message exceeds fixed maximum message size)
1407 Delete the message from the server. Send bounce-mail to the
1410 553 (invalid sending domain)
1411 Delete the message from the server. Don't even try to send
1412 bounce-mail to the originator.
1414 Other errors trigger bounce mail back to the originator. See also BUGS.
1416 .SH THE RUN CONTROL FILE
1417 The preferred way to set up fetchmail is to write a
1418 \&\fI.fetchmailrc\fR file in your home directory (you may do this
1419 directly, with a text editor, or indirectly via \fIfetchmailconf\fR).
1420 When there is a conflict between the command-line arguments and the
1421 arguments in this file, the command-line arguments take precedence.
1423 To protect the security of your passwords,
1424 your \fI~/.fetchmailrc\fR may not normally have more than 0600 (u=rw,g=,o=) permissions;
1426 will complain and exit otherwise (this check is suppressed when
1429 You may read the \fI.fetchmailrc\fR file as a list of commands to
1432 is called with no arguments.
1433 .SS Run Control Syntax
1435 Comments begin with a '#' and extend through the end of the line.
1436 Otherwise the file consists of a series of server entries or global
1437 option statements in a free-format, token-oriented syntax.
1439 There are four kinds of tokens: grammar keywords, numbers
1440 (i.e. decimal digit sequences), unquoted strings, and quoted strings.
1441 A quoted string is bounded by double quotes and may contain
1442 whitespace (and quoted digits are treated as a string). Note that
1443 quoted strings will also contain line feed characters if they run across
1444 two or more lines, unless you use a backslash to join lines (see below).
1445 An unquoted string is any whitespace-delimited token that is neither
1446 numeric, string quoted nor contains the special characters ',', ';',
1449 Any amount of whitespace separates tokens in server entries, but is
1450 otherwise ignored. You may use backslash escape sequences (\en for LF,
1451 \&\et for HT, \eb for BS, \er for CR, \e\fInnn\fP for decimal (where
1452 nnn cannot start with a 0), \e0\fIooo\fP for octal, and \ex\fIhh\fP for
1453 hex) to embed non-printable characters or string delimiters in strings.
1454 In quoted strings, a backslash at the very end of a line will cause the
1455 backslash itself and the line feed (LF or NL, new line) character to be
1456 ignored, so that you can wrap long strings. Without the backslash at the
1457 line end, the line feed character would become part of the string.
1460 while these resemble C-style escape sequences, they are not the same.
1461 fetchmail only supports these eight styles. C supports more escape
1462 sequences that consist of backslash (\e) and a single character, but
1463 does not support decimal codes and does not require the leading 0 in
1464 octal notation. Example: fetchmail interprets \e233 the same as \exE9
1465 (Latin small letter e with acute), where C would interpret \e233 as
1466 octal 0233 = \ex9B (CSI, control sequence introducer).
1468 Each server entry consists of one of the keywords 'poll' or 'skip',
1469 followed by a server name, followed by server options, followed by any
1470 number of user descriptions. Note: the most common cause of syntax
1471 errors is mixing up user and server options.
1473 For backward compatibility, the word 'server' is a synonym for 'poll'.
1475 You can use the noise keywords 'and', 'with',
1476 \&'has', 'wants', and 'options' anywhere in an entry to make
1477 it resemble English. They're ignored, but but can make entries much
1478 easier to read at a glance. The punctuation characters ':', ';' and
1479 \&',' are also ignored.
1482 The 'poll' verb tells fetchmail to query this host when it is run with
1483 no arguments. The 'skip' verb tells
1485 not to poll this host unless it is explicitly named on the command
1486 line. (The 'skip' verb allows you to experiment with test entries
1487 safely, or easily disable entries for hosts that are temporarily down.)
1489 .SS Keyword/Option Summary
1490 Here are the legal options. Keyword suffixes enclosed in
1491 square brackets are optional. Those corresponding to short command-line
1492 options are followed by '\-' and the appropriate option letter. If
1493 option is only relevant to a single mode of operation, it is noted as
1494 \&'s' or 'm' for singledrop- or multidrop-mode, respectively.
1496 Here are the legal global options:
1500 Keyword Opt Mode Function
1502 set daemon \-d \& T{
1503 Set a background poll interval in seconds.
1505 set postmaster \& \& T{
1506 Give the name of the last-resort mail recipient (default: user running
1507 fetchmail, "postmaster" if run by the root user)
1509 set bouncemail \& \& T{
1510 Direct error mail to the sender (default)
1512 set no bouncemail \& \& T{
1513 Direct error mail to the local postmaster (as per the 'postmaster'
1514 global option above).
1516 set no spambounce \& \& T{
1517 Do not bounce spam-blocked mail (default).
1519 set spambounce \& \& T{
1520 Bounce blocked spam-blocked mail (as per the 'antispam' user option)
1521 back to the destination as indicated by the 'bouncemail' global option.
1522 Warning: Do not use this to bounce spam back to the sender - most spam
1523 is sent with false sender address and thus this option hurts innocent
1526 set logfile \-L \& T{
1527 Name of a file to append error and status messages to.
1529 set idfile \-i \& T{
1530 Name of the file to store UID lists in.
1533 Do error logging through syslog(3).
1535 set no syslog \& \& T{
1536 Turn off error logging through syslog(3). (default)
1538 set properties \& \& T{
1539 String value that is ignored by fetchmail (may be used by extension
1544 Here are the legal server options:
1548 Keyword Opt Mode Function
1551 Specify DNS name of mailserver, overriding poll name
1553 proto[col] \-p \& T{
1554 Specify protocol (case insensitive):
1555 POP2, POP3, IMAP, APOP, KPOP
1557 local[domains] \& m T{
1558 Specify domain(s) to be regarded as local
1561 Specify TCP/IP service port (obsolete, use 'service' instead).
1564 Specify service name (a numeric value is also allowed and
1565 considered a TCP/IP port number).
1567 auth[enticate] \& \& T{
1568 Set authentication type (default 'any')
1571 Server inactivity timeout in seconds (default 300)
1574 Specify envelope-address header name
1577 Disable looking for envelope address
1580 Qmail virtual domain prefix to remove from user name
1583 Specify alternate DNS names of mailserver
1586 specify IP interface(s) that must be up for server poll to take place
1589 Specify IP address to monitor for activity
1592 Specify command through which to make server connections.
1595 Specify command through which to make listener connections.
1598 Enable DNS lookup for multidrop (default)
1601 Disable DNS lookup for multidrop
1604 Do comparison by IP address for multidrop
1606 no checkalias \& m T{
1607 Do comparison by name for multidrop (default)
1610 Force POP3 to use client-side UIDLs (recommended)
1613 Turn off POP3 use of client-side UIDLs (default)
1616 Only check this site every N poll cycles; N is a numeric argument.
1619 Add poll tracing information to the Received header
1622 Set Kerberos principal (only useful with IMAP and kerberos)
1625 Set name for RFC2554 authentication to the ESMTP server.
1627 esmtppassword \& \& T{
1628 Set password for RFC2554 authentication to the ESMTP server.
1632 Here are the legal user options:
1636 Keyword Opt Mode Function
1638 user[name] \-u \& T{
1639 Set remote user name
1640 (local user name if name followed by 'here')
1643 Connect local and remote user names
1646 Connect local and remote user names
1649 Specify remote account password
1652 Connect to server over the specified base protocol using SSL encryption
1655 Specify file for client side public SSL certificate
1658 Specify file for client side private SSL key
1661 Force ssl protocol for connection
1664 Specify remote folder to query
1667 Specify smtp host(s) to forward to
1669 fetchdomains \& m T{
1670 Specify domains for which mail should be fetched
1672 smtpaddress \-D \& T{
1673 Specify the domain to be put in RCPT TO lines
1676 Specify the user and domain to be put in RCPT TO lines
1679 Specify what SMTP returns are interpreted as spam-policy blocks
1682 Specify MDA for local delivery
1685 Specify BSMTP batch file to append to
1688 Command to be executed before each connection
1690 postconnect \& \& T{
1691 Command to be executed after each connection
1694 Don't delete seen messages from server (for POP3, uidl is recommended)
1697 Flush all seen messages before querying (DANGEROUS)
1700 Flush all oversized messages before querying
1703 Fetch all messages whether seen or not
1706 Rewrite destination addresses for reply (default)
1709 Strip carriage returns from ends of lines
1712 Force carriage returns at ends of lines
1715 Force BODY=8BITMIME to ESMTP listener
1718 Strip Status and X-Mozilla-Status lines out of incoming mail
1720 dropdelivered \& \& T{
1721 Strip Delivered-To lines out of incoming mail
1724 Convert quoted-printable to 8-bit in MIME messages
1727 Idle waiting for new messages after each poll (IMAP only)
1730 Delete seen messages from server (default)
1733 Don't flush all seen messages before querying (default)
1735 no fetchall \& \& T{
1736 Retrieve only new messages (default)
1739 Don't rewrite headers
1742 Don't strip carriage returns (default)
1745 Don't force carriage returns at EOL (default)
1747 no pass8bits \& \& T{
1748 Don't force BODY=8BITMIME to ESMTP listener (default)
1750 no dropstatus \& \& T{
1751 Don't drop Status headers (default)
1753 no dropdelivered \& \& T{
1754 Don't drop Delivered\-To headers (default)
1756 no mimedecode \& \& T{
1757 Don't convert quoted-printable to 8-bit in MIME messages (default)
1760 Don't idle waiting for new messages after each poll (IMAP only)
1763 Set message size limit
1766 Set message size warning interval
1768 batchlimit \-b \& T{
1769 Max # messages to forward in single connect
1771 fetchlimit \-B \& T{
1772 Max # messages to fetch in single connect
1774 fetchsizelimit \& \& T{
1775 Max # message sizes to fetch in single transaction
1778 Use binary search for first unseen message (POP3 only)
1781 Perform an expunge on every #th message (IMAP and POP3 only)
1784 String value is ignored by fetchmail (may be used by extension scripts)
1788 Remember that all user options must \fIfollow\fR all server options.
1790 In the .fetchmailrc file, the 'envelope' string argument may be
1791 preceded by a whitespace-separated number. This number, if specified,
1792 is the number of such headers to skip over (that is, an argument of 1
1793 selects the second header of the given type). This is sometime useful
1794 for ignoring bogus envelope headers created by an ISP's local delivery
1795 agent or internal forwards (through mail inspection systems, for
1797 .SS Keywords Not Corresponding To Option Switches
1799 The 'folder' and 'smtphost' options (unlike their command-line
1800 equivalents) can take a space- or comma-separated list of names
1803 All options correspond to the obvious command-line arguments, except
1804 the following: 'via', 'interval', 'aka', 'is', 'to', 'dns'/'no dns',
1805 \&'checkalias'/'no checkalias', 'password', 'preconnect', 'postconnect',
1806 \&'localdomains', 'stripcr'/'no stripcr', 'forcecr'/'no forcecr',
1807 \&'pass8bits'/'no pass8bits' 'dropstatus/no dropstatus',
1808 \&'dropdelivered/no dropdelivered', 'mimedecode/no mimedecode', 'no idle',
1811 The 'via' option is for if you want to have more
1812 than one configuration pointing at the same site. If it is present,
1813 the string argument will be taken as the actual DNS name of the
1814 mailserver host to query.
1815 This will override the argument of poll, which can then simply be a
1816 distinct label for the configuration (e.g. what you would give on the
1817 command line to explicitly query this host).
1819 The 'interval' option (which takes a numeric argument) allows you to poll a
1820 server less frequently than the basic poll interval. If you say
1821 \&'interval N' the server this option is attached to will only be
1822 queried every N poll intervals.
1823 .SS Singledrop vs. Multidrop options
1825 The 'is' or 'to' keywords associate the following local (client)
1826 name(s) (or server-name to client-name mappings separated by =) with
1827 the mailserver user name in the entry. If an is/to list has '*' as
1828 its last name, unrecognized names are simply passed through. Note that
1829 until \fIfetchmail\fR version 6.3.4 inclusively, these lists could only
1830 contain local parts of user names (fetchmail would only look at the part
1831 before the @ sign). \fIfetchmail\fR versions 6.3.5 and
1832 newer support full addresses on the left hand side of these mappings,
1833 and they take precedence over any 'localdomains', 'aka', 'via' or
1836 A single local name can be used to support redirecting your mail when
1837 your username on the client machine is different from your name on the
1838 mailserver. When there is only a single local name, mail is forwarded
1839 to that local username regardless of the message's Received, To, Cc,
1840 and Bcc headers. In this case,
1842 never does DNS lookups.
1844 When there is more than one local name (or name mapping),
1845 \fIfetchmail\fR looks at the envelope header, if configured, and
1846 otherwise at the Received, To, Cc, and Bcc headers of retrieved mail
1847 (this is 'multidrop mode'). It looks for addresses with hostname parts
1848 that match your poll name or your 'via', 'aka' or 'localdomains'
1849 options, and usually also for hostname parts which DNS tells it are
1850 aliases of the mailserver. See the discussion of 'dns', 'checkalias',
1851 \&'localdomains', and 'aka' for details on how matching addresses are
1854 If \fIfetchmail\fR cannot match any mailserver usernames or
1855 localdomain addresses, the mail will be bounced.
1856 Normally it will be bounced to the sender, but if the 'bouncemail'
1857 global option is off, the mail will go to the local postmaster instead.
1858 (see the 'postmaster' global option). See also BUGS.
1860 The 'dns' option (normally on) controls the way addresses from
1861 multidrop mailboxes are checked. On, it enables logic to check each
1862 host address that does not match an 'aka' or 'localdomains' declaration
1863 by looking it up with DNS. When a mailserver username is recognized
1864 attached to a matching hostname part, its local mapping is added to
1865 the list of local recipients.
1867 The 'checkalias' option (normally off) extends the lookups performed
1868 by the 'dns' keyword in multidrop mode, providing a way to cope with
1869 remote MTAs that identify themselves using their canonical name, while
1870 they're polled using an alias.
1871 When such a server is polled, checks to extract the envelope address
1874 reverts to delivery using the To/Cc/Bcc headers (See below
1875 \&'Header vs. Envelope addresses').
1876 Specifying this option instructs
1878 to retrieve all the IP addresses associated with both the poll name
1879 and the name used by the remote MTA and to do a comparison of the IP
1880 addresses. This comes in handy in situations where the remote server
1881 undergoes frequent canonical name changes, that would otherwise
1882 require modifications to the rcfile. 'checkalias' has no effect if
1883 \&'no dns' is specified in the rcfile.
1885 The 'aka' option is for use with multidrop mailboxes. It allows you
1886 to pre-declare a list of DNS aliases for a server. This is an
1887 optimization hack that allows you to trade space for speed. When
1889 while processing a multidrop mailbox, grovels through message headers
1890 looking for names of the mailserver, pre-declaring common ones can
1891 save it from having to do DNS lookups. Note: the names you give
1892 as arguments to 'aka' are matched as suffixes -- if you specify
1893 (say) 'aka netaxs.com', this will match not just a hostname
1894 netaxs.com, but any hostname that ends with '.netaxs.com'; such as
1895 (say) pop3.netaxs.com and mail.netaxs.com.
1897 The 'localdomains' option allows you to declare a list of domains
1898 which fetchmail should consider local. When fetchmail is parsing
1899 address lines in multidrop modes, and a trailing segment of a host
1900 name matches a declared local domain, that address is passed through
1901 to the listener or MDA unaltered (local-name mappings are \fInot\fR
1904 If you are using 'localdomains', you may also need to specify 'no
1905 envelope', which disables \fIfetchmail\fR's normal attempt to deduce
1906 an envelope address from the Received line or X-Envelope-To header or
1907 whatever header has been previously set by 'envelope'. If you set 'no
1908 envelope' in the defaults entry it is possible to undo that in
1909 individual entries by using 'envelope <string>'. As a special case,
1910 \&'envelope "Received"' restores the default parsing of
1913 The \fBpassword\fR option requires a string argument, which is the password
1914 to be used with the entry's server.
1916 The 'preconnect' keyword allows you to specify a shell command to be
1917 executed just before each time
1919 establishes a mailserver connection. This may be useful if you are
1920 attempting to set up secure POP connections with the aid of
1922 If the command returns a nonzero status, the poll of that mailserver
1925 Similarly, the 'postconnect' keyword similarly allows you to specify a
1926 shell command to be executed just after each time a mailserver
1927 connection is taken down.
1929 The 'forcecr' option controls whether lines terminated by LF only are
1930 given CRLF termination before forwarding. Strictly speaking RFC821
1931 requires this, but few MTAs enforce the requirement it so this option
1932 is normally off (only one such MTA, qmail, is in significant use at
1935 The 'stripcr' option controls whether carriage returns are stripped
1936 out of retrieved mail before it is forwarded. It is normally not
1937 necessary to set this, because it defaults to 'on' (CR stripping
1938 enabled) when there is an MDA declared but 'off' (CR stripping
1939 disabled) when forwarding is via SMTP. If 'stripcr' and 'forcecr' are
1940 both on, 'stripcr' will override.
1942 The 'pass8bits' option exists to cope with Microsoft mail programs that
1943 stupidly slap a "Content-Transfer-Encoding: 7bit" on everything. With
1944 this option off (the default) and such a header present,
1946 declares BODY=7BIT to an ESMTP-capable listener; this causes problems for
1947 messages actually using 8-bit ISO or KOI-8 character sets, which will
1948 be garbled by having the high bits of all characters stripped. If
1949 \&'pass8bits' is on,
1951 is forced to declare BODY=8BITMIME to any ESMTP-capable listener. If
1952 the listener is 8-bit-clean (as all the major ones now are) the right
1953 thing will probably result.
1955 The 'dropstatus' option controls whether nonempty Status and
1956 X-Mozilla-Status lines are retained in fetched mail (the default) or
1957 discarded. Retaining them allows your MUA to see what messages (if
1958 any) were marked seen on the server. On the other hand, it can
1959 confuse some new-mail notifiers, which assume that anything with a
1960 Status line in it has been seen. (Note: the empty Status lines
1961 inserted by some buggy POP servers are unconditionally discarded.)
1963 The 'dropdelivered' option controls whether Delivered\-To headers will
1964 be kept in fetched mail (the default) or discarded. These headers are
1965 added by Qmail and Postfix mailservers in order to avoid mail loops but
1966 may get in your way if you try to "mirror" a mailserver within the same
1967 domain. Use with caution.
1969 The 'mimedecode' option controls whether MIME messages using the
1970 quoted-printable encoding are automatically converted into pure 8-bit
1971 data. If you are delivering mail to an ESMTP-capable, 8-bit-clean
1972 listener (that includes all of the major MTAs like sendmail), then
1973 this will automatically convert quoted-printable message headers and
1974 data into 8-bit data, making it easier to understand when reading
1975 mail. If your e-mail programs know how to deal with MIME messages,
1976 then this option is not needed. The mimedecode option is off by
1977 default, because doing RFC2047 conversion on headers throws away
1978 character-set information and can lead to bad results if the encoding
1979 of the headers differs from the body encoding.
1981 The 'idle' option is intended to be used with IMAP servers supporting
1982 the RFC2177 IDLE command extension, but does not strictly require it.
1983 If it is enabled, and fetchmail detects that IDLE is supported, an
1984 IDLE will be issued at the end of each poll. This will tell the IMAP
1985 server to hold the connection open and notify the client when new mail
1986 is available. If IDLE is not supported, fetchmail will simulate it by
1987 periodically issuing NOOP. If you need to poll a link frequently, IDLE
1988 can save bandwidth by eliminating TCP/IP connects and LOGIN/LOGOUT
1989 sequences. On the other hand, an IDLE connection will eat almost all
1990 of your fetchmail's time, because it will never drop the connection
1991 and allow other polls to occur unless the server times out the IDLE.
1992 It also doesn't work with multiple folders; only the first folder will
1996 The 'properties' option is an extension mechanism. It takes a string
1997 argument, which is ignored by fetchmail itself. The string argument may be
1998 used to store configuration information for scripts which require it.
1999 In particular, the output of '\-\-configdump' option will make properties
2000 associated with a user entry readily available to a Python script.
2002 .SS Miscellaneous Run Control Options
2003 The words 'here' and 'there' have useful English-like
2004 significance. Normally 'user eric is esr' would mean that
2005 mail for the remote user 'eric' is to be delivered to 'esr',
2006 but you can make this clearer by saying 'user eric there is esr here',
2007 or reverse it by saying 'user esr here is eric there'
2009 Legal protocol identifiers for use with the 'protocol' keyword are:
2012 auto (or AUTO) (legacy, to be removed from future release)
2013 pop2 (or POP2) (legacy, to be removed from future release)
2022 Legal authentication types are 'any', 'password', 'kerberos',
2023 \&'kerberos_v4', 'kerberos_v5' and 'gssapi', 'cram\-md5', 'otp', 'msn'
2024 (only for POP3), 'ntlm', 'ssh', 'external' (only IMAP).
2025 The 'password' type specifies
2026 authentication by normal transmission of a password (the password may be
2027 plain text or subject to protocol-specific encryption as in APOP);
2028 \&'kerberos' tells \fIfetchmail\fR to try to get a Kerberos ticket at the
2029 start of each query instead, and send an arbitrary string as the
2030 password; and 'gssapi' tells fetchmail to use GSSAPI authentication.
2031 See the description of the 'auth' keyword for more.
2033 Specifying 'kpop' sets POP3 protocol over port 1109 with Kerberos V4
2034 authentication. These defaults may be overridden by later options.
2036 There are some global option statements: 'set logfile'
2037 followed by a string sets the same global specified by \-\-logfile. A
2038 command-line \-\-logfile option will override this. Note that \-\-logfile is
2039 only effective if fetchmail detaches itself from the terminal. Also,
2040 \&'set daemon' sets the poll interval as \-\-daemon does. This can be
2041 overridden by a command-line \-\-daemon option; in particular \-\-daemon\~0
2042 can be used to force foreground operation. The 'set postmaster'
2043 statement sets the address to which multidrop mail defaults if there are
2044 no local matches. Finally, 'set syslog' sends log messages to
2047 .SH DEBUGGING FETCHMAIL
2048 .SS Fetchmail crashing
2049 There are various ways in that fetchmail may "crash", i. e. stop
2050 operation suddenly and unexpectedly. A "crash" usually refers to an
2051 error condition that the software did not handle by itself. A well-known
2052 failure mode is the "segmentation fault" or "signal 11" or "SIGSEGV" or
2053 just "segfault" for short. These can be caused by hardware or by software
2054 problems. Software-induced segfaults can usually be reproduced easily
2055 and in the same place, whereas hardware-induced segfaults can go away if
2056 the computer is rebooted, or powered off for a few hours, and can happen
2057 in random locations even if you use the software the same way.
2059 For solving hardware-induced segfaults, find the faulty component and repair or
2060 replace it. <http://www.bitwizard.nl/sig11/> may help you with details.
2062 For solving software-induced segfaults, the developers may need a "stack
2065 .SS Enabling fetchmail core dumps
2066 By default, fetchmail suppresses core dumps as these might contain
2067 passwords and other sensitive information. For debugging fetchmail
2068 crashes, obtaining a "stack backtrace" from a core dump is often the
2069 quickest way to solve the problem, and when posting your problem on a
2070 mailing list, the developers may ask you for a "backtrace".
2072 1. To get useful backtraces, fetchmail needs to be installed without
2073 getting stripped of its compilation symbols. Unfortunately, most
2074 binary packages that are installed are stripped, and core files from
2075 symbol-stripped programs are worthless. So you may need to recompile
2076 fetchmail. On many systems, you can type
2079 file `which fetchmail`
2082 to find out if fetchmail was symbol-stripped or not. If yours was
2083 unstripped, fine, proceed, if it was stripped, you need to recompile the
2084 source code first. You do not usually need to install fetchmail in order
2087 2. The shell environment that starts fetchmail needs to enable core
2088 dumps. The key is the "maximum core (file) size" that can usually be
2089 configured with a tool named "limit" or "ulimit". See the documentation
2090 for your shell for details. In the popular bash shell, "ulimit \-Sc
2091 unlimited" will allow the core dump.
2093 3. You need to tell fetchmail, too, to allow core dumps. To do
2094 this, run fetchmail with the \fB\-d0 \-v\fP options. It is often easier
2095 to also add \fB\-\-nosyslog \-N\fR as well.
2097 Finally, you need to reproduce the crash. You can just start fetchmail
2098 from the directory where you compiled it by typing \fB./fetchmail\fR,
2099 so the complete command line will start with \fB./fetchmail \-Nvd0
2100 \&\-\-nosyslog\fR and perhaps list your other options.
2102 After the crash, run your debugger to obtain the core dump. The
2103 debugger will often be GNU GDB, you can then type (adjust paths as
2104 necessary) \fBgdb ./fetchmail fetchmail.core\fR and then, after GDB
2105 has started up and read all its files, type \fBbacktrace full\fR, save
2106 the output (copy & paste will do, the backtrace will be read by a human)
2107 and then type \fBquit\fR to leave gdb.
2109 on some systems, the core
2110 files have different names, they might contain a number instead of the
2111 program name, or number and name, but it will usually have "core" as
2114 .SH INTERACTION WITH RFC 822
2115 When trying to determine the originating address of a message,
2116 fetchmail looks through headers in the following order:
2120 Resent-Sender: (ignored if it doesn't contain an @ or !)
2121 Sender: (ignored if it doesn't contain an @ or !)
2128 The originating address is used for logging, and to set the MAIL FROM
2129 address when forwarding to SMTP. This order is intended to cope
2130 gracefully with receiving mailing list messages in multidrop mode. The
2131 intent is that if a local address doesn't exist, the bounce message
2132 won't be returned blindly to the author or to the list itself, but
2133 rather to the list manager (which is less annoying).
2135 In multidrop mode, destination headers are processed as follows:
2136 First, fetchmail looks for the Received: header (or whichever one is
2137 specified by the 'envelope' option) to determine the local
2138 recipient address. If the mail is addressed to more than one recipient,
2139 the Received line won't contain any information regarding recipient addresses.
2141 Then fetchmail looks for the Resent-To:, Resent-Cc:, and Resent-Bcc:
2142 lines. If they exist, they should contain the final recipients and
2143 have precedence over their To:/Cc:/Bcc: counterparts. If the Resent\-*
2144 lines don't exist, the To:, Cc:, Bcc: and Apparently-To: lines are
2145 looked for. (The presence of a Resent\-To: is taken to imply that the
2146 person referred by the To: address has already received the original
2149 .SH CONFIGURATION EXAMPLES
2150 Note that although there are password declarations in a good many
2151 of the examples below, this is mainly for illustrative purposes.
2152 We recommend stashing account/password pairs in your $HOME/.netrc
2153 file, where they can be used not just by fetchmail but by ftp(1) and
2159 poll SERVERNAME protocol PROTOCOL username NAME password PASSWORD
2165 poll pop.provider.net protocol pop3 username "jsmith" password "secret1"
2168 Or, using some abbreviations:
2171 poll pop.provider.net proto pop3 user "jsmith" password "secret1"
2174 Multiple servers may be listed:
2177 poll pop.provider.net proto pop3 user "jsmith" pass "secret1"
2178 poll other.provider.net proto pop2 user "John.Smith" pass "My^Hat"
2181 Here's a version of those two with more whitespace and some noise words:
2184 poll pop.provider.net proto pop3
2185 user "jsmith", with password secret1, is "jsmith" here;
2186 poll other.provider.net proto pop2:
2187 user "John.Smith", with password "My^Hat", is "John.Smith" here;
2190 This version is much easier to read and doesn't cost significantly
2191 more (parsing is done only once, at startup time).
2194 If you need to include whitespace in a parameter string, enclose the
2195 string in double quotes. Thus:
2198 poll mail.provider.net with proto pop3:
2199 user "jsmith" there has password "u can't krak this"
2200 is jws here and wants mda "/bin/mail"
2203 You may have an initial server description headed by the keyword
2204 \&'defaults' instead of 'poll' followed by a name. Such a record
2205 is interpreted as defaults for all queries to use. It may be overwritten
2206 by individual server descriptions. So, you could write:
2211 poll pop.provider.net
2213 poll mail.provider.net
2214 user "jjsmith" there has password "secret2"
2217 It's possible to specify more than one user per server (this is only
2218 likely to be useful when running fetchmail in daemon mode as root).
2219 The 'user' keyword leads off a user description, and every user specification
2220 in a multi-user entry must include it. Here's an example:
2223 poll pop.provider.net proto pop3 port 3111
2224 user "jsmith" with pass "secret1" is "smith" here
2225 user jones with pass "secret2" is "jjones" here keep
2228 This associates the local username 'smith' with the pop.provider.net
2229 username 'jsmith' and the local username 'jjones' with the
2230 pop.provider.net username 'jones'. Mail for 'jones' is kept on the
2231 server after download.
2233 Here's what a simple retrieval configuration for a multidrop mailbox
2237 poll pop.provider.net:
2238 user maildrop with pass secret1 to golux 'hurkle'='happy' snark here
2241 This says that the mailbox of account 'maildrop' on the server is a
2242 multidrop box, and that messages in it should be parsed for the
2243 server user names 'golux', 'hurkle', and 'snark'. It further
2244 specifies that 'golux' and 'snark' have the same name on the
2245 client as on the server, but mail for server user 'hurkle' should be
2246 delivered to client user 'happy'.
2251 until version 6.3.4, did NOT allow full user@domain specifications here,
2252 these would never match. \fIFetchmail\fP 6.3.5 and newer support
2253 user@domain specifications on the left-hand side of a user mapping.
2255 Here's an example of another kind of multidrop connection:
2258 poll pop.provider.net localdomains loonytoons.org toons.org:
2259 user maildrop with pass secret1 to * here
2262 This also says that the mailbox of account 'maildrop' on the server is
2263 a multidrop box. It tells fetchmail that any address in the
2264 loonytoons.org or toons.org domains (including sub-domain addresses like
2265 \&'joe@daffy.loonytoons.org') should be passed through to the local SMTP
2266 listener without modification. Be careful of mail loops if you do this!
2268 Here's an example configuration using ssh and the plugin option. The
2269 queries are made directly on the stdin and stdout of imapd via ssh.
2270 Note that in this setup, IMAP authentication can be skipped.
2273 poll mailhost.net with proto imap:
2274 plugin "ssh %h /usr/sbin/imapd" auth ssh;
2275 user esr is esr here
2278 .SH THE USE AND ABUSE OF MULTIDROP MAILBOXES
2279 Use the multiple-local-recipients feature with caution -- it can bite.
2280 All multidrop features are ineffective in ETRN and ODMR modes.
2282 Also, note that in multidrop mode duplicate mails are suppressed. A
2283 piece of mail is considered duplicate if it has the same message-ID as
2284 the message immediately preceding and more than one addressee. Such
2285 runs of messages may be generated when copies of a message addressed
2286 to multiple users are delivered to a multidrop box.
2288 .SS Header vs. Envelope addresses
2289 The fundamental problem is that by having your mailserver toss several
2290 peoples' mail in a single maildrop box, you may have thrown away
2291 potentially vital information about who each piece of mail was
2292 actually addressed to (the 'envelope address', as opposed to the
2293 header addresses in the RFC822 To/Cc headers - the Bcc is not available
2294 at the receiving end). This 'envelope address' is the address you need
2295 in order to reroute mail properly.
2299 can deduce the envelope address. If the mailserver MTA is
2301 and the item of mail had just one recipient, the MTA will have written
2302 a 'by/for' clause that gives the envelope addressee into its Received
2303 header. But this doesn't work reliably for other MTAs, nor if there is
2304 more than one recipient. By default, \fIfetchmail\fR looks for
2305 envelope addresses in these lines; you can restore this default with
2306 \&\-E "Received" or 'envelope Received'.
2308 .B As a better alternative,
2309 some SMTP listeners and/or mail servers insert a header
2310 in each message containing a copy of the envelope addresses. This
2311 header (when it exists) is often 'X\-Original\-To', 'Delivered\-To' or
2312 \&'X\-Envelope\-To'. Fetchmail's assumption about this can be changed with
2313 the \-E or 'envelope' option. Note that writing an envelope header of
2314 this kind exposes the names of recipients (including blind-copy
2315 recipients) to all receivers of the messages, so the upstream must store
2316 one copy of the message per recipient to avoid becoming a privacy problem.
2318 Postfix, since version 2.0, writes an X\-Original\-To: header which
2319 contains a copy of the envelope as it was received.
2321 Qmail and Postfix generally write a 'Delivered\-To' header upon
2322 delivering the message to the mail spool and use it to avoid mail loops.
2323 Qmail virtual domains however will prefix the user name with a string
2324 that normally matches the user's domain. To remove this prefix you can
2325 use the \-Q or 'qvirtual' option.
2327 Sometimes, unfortunately, neither of these methods works. That is the
2328 point when you should contact your ISP and ask them to provide such an
2329 envelope header, and you should not use multidrop in this situation.
2330 When they all fail, fetchmail must fall back on the contents of To/Cc
2331 headers (Bcc headers are not available - see below) to try to determine
2332 recipient addressees -- and these are unreliable.
2333 In particular, mailing-list software often ships mail with only
2334 the list broadcast address in the To header.
2336 .B Note that a future version of \fIfetchmail\fP may remove To/Cc parsing!
2340 cannot deduce a recipient address that is local, and the intended
2341 recipient address was anyone other than fetchmail's invoking user,
2342 .B mail will get lost.
2343 This is what makes the multidrop feature risky without proper envelope
2346 A related problem is that when you blind-copy a mail message, the Bcc
2347 information is carried \fIonly\fR as envelope address (it's removed from
2348 the headers by the sending mail server, so fetchmail can see it only if
2349 there is an X-\Envelope\-To header). Thus, blind-copying to someone who
2350 gets mail over a fetchmail multidrop link will fail unless the the
2351 mailserver host routinely writes X\-Envelope\-To or an equivalent header
2352 into messages in your maildrop.
2354 \fBIn conclusion, mailing lists and Bcc'd mail can only work if the
2355 server you're fetching from (1) stores one copy of the message per
2356 recipient in \fIyour\fP domain and (2) records the envelope
2357 information in a special header (X\-Original\-To, Delivered\-To,
2358 X\-Envelope\-To).\fR
2360 .SS Good Ways To Use Multidrop Mailboxes
2361 Multiple local names can be used to administer a mailing list from the
2362 client side of a \fIfetchmail\fR collection. Suppose your name is
2363 \&'esr', and you want to both pick up your own mail and maintain a mailing
2364 list called (say) "fetchmail-friends", and you want to keep the alias
2365 list on your client machine.
2367 On your server, you can alias 'fetchmail\-friends' to 'esr'; then, in
2368 your \fI.fetchmailrc\fR, declare 'to esr fetchmail\-friends here'.
2369 Then, when mail including 'fetchmail\-friends' as a local address
2370 gets fetched, the list name will be appended to the list of
2371 recipients your SMTP listener sees. Therefore it will undergo alias
2372 expansion locally. Be sure to include 'esr' in the local alias
2373 expansion of fetchmail\-friends, or you'll never see mail sent only to
2374 the list. Also be sure that your listener has the "me-too" option set
2375 (sendmail's \-oXm command-line option or OXm declaration) so your name
2376 isn't removed from alias expansions in messages you send.
2378 This trick is not without its problems, however. You'll begin to see
2379 this when a message comes in that is addressed only to a mailing list
2380 you do \fInot\fR have declared as a local name. Each such message
2381 will feature an 'X\-Fetchmail\-Warning' header which is generated
2382 because fetchmail cannot find a valid local name in the recipient
2383 addresses. Such messages default (as was described above) to being
2384 sent to the local user running
2386 but the program has no way to know that that's actually the right thing.
2388 .SS Bad Ways To Abuse Multidrop Mailboxes
2389 Multidrop mailboxes and
2391 serving multiple users in daemon mode do not mix. The problem, again, is
2392 mail from mailing lists, which typically does not have an individual
2393 recipient address on it. Unless
2395 can deduce an envelope address, such mail will only go to the account
2396 running fetchmail (probably root). Also, blind-copied users are very
2397 likely never to see their mail at all.
2399 If you're tempted to use
2401 to retrieve mail for multiple users from a single mail drop via POP or
2402 IMAP, think again (and reread the section on header and envelope
2403 addresses above). It would be smarter to just let the mail sit in the
2404 mailserver's queue and use fetchmail's ETRN or ODMR modes to trigger
2405 SMTP sends periodically (of course, this means you have to poll more
2406 frequently than the mailserver's expiry period). If you can't arrange
2407 this, try setting up a UUCP feed.
2409 If you absolutely \fImust\fR use multidrop for this purpose, make sure
2410 your mailserver writes an envelope-address header that fetchmail can
2411 see. Otherwise you \fIwill\fR lose mail and it \fIwill\fR come back
2414 .SS Speeding Up Multidrop Checking
2415 Normally, when multiple users are declared
2417 extracts recipient addresses as described above and checks each host
2418 part with DNS to see if it's an alias of the mailserver. If so, the
2419 name mappings described in the "to ... here" declaration are done and
2420 the mail locally delivered.
2422 This is a convenient but also slow method. To speed
2423 it up, pre-declare mailserver aliases with 'aka'; these are checked
2424 before DNS lookups are done. If you're certain your aka list contains
2426 DNS aliases of the mailserver (and all MX names pointing at it - note
2427 this may change in a future version)
2428 you can declare 'no dns' to suppress DNS lookups entirely and
2429 \fIonly\fR match against the aka list.
2432 To facilitate the use of
2434 in shell scripts, an exit\ status code is returned to give an indication
2435 of what occurred during a given connection.
2437 The exit codes returned by
2441 One or more messages were successfully retrieved (or, if the \-c option
2442 was selected, were found waiting but not retrieved).
2444 There was no mail awaiting retrieval. (There may have been old mail still
2445 on the server but not selected for retrieval.)
2447 An error was encountered when attempting to open a socket to retrieve
2448 mail. If you don't know what a socket is, don't worry about it --
2449 just treat this as an 'unrecoverable error'. This error can also be
2450 because a protocol fetchmail wants to use is not listed in /etc/services.
2452 The user authentication step failed. This usually means that a bad
2453 user-id, password, or APOP id was specified. Or it may mean that you
2454 tried to run fetchmail under circumstances where it did not have
2455 standard input attached to a terminal and could not prompt for a
2458 Some sort of fatal protocol error was detected.
2460 There was a syntax error in the arguments to
2463 The run control file had bad permissions.
2465 There was an error condition reported by the server. Can also
2468 timed out while waiting for the server.
2470 Client-side exclusion error. This means
2472 either found another copy of itself already running, or failed in such
2473 a way that it isn't sure whether another copy is running.
2475 The user authentication step failed because the server responded "lock
2476 busy". Try again after a brief pause! This error is not implemented
2477 for all protocols, nor for all servers. If not implemented for your
2478 server, "3" will be returned instead, see above. May be returned when
2479 talking to qpopper or other servers that can respond with "lock busy"
2480 or some similar text containing the word "lock".
2484 run failed while trying to do an SMTP port open or transaction.
2486 Fatal DNS error. Fetchmail encountered an error while performing
2487 a DNS lookup at startup and could not proceed.
2489 BSMTP batch file could not be opened.
2491 Poll terminated by a fetch limit (see the \-\-fetchlimit option).
2493 Server busy indication.
2495 Internal error. You should see a message on standard error with
2498 These are internal codes and should not appear externally.
2502 queries more than one host, return status is 0 if \fIany\fR query
2503 successfully retrieved mail. Otherwise the returned error status is
2504 that of the last host queried.
2509 default run control file
2512 default location of file associating hosts with last message IDs seen
2513 (used only with newer RFC1939-compliant POP3 servers supporting the
2517 lock file to help prevent concurrent runs (non-root mode).
2520 your FTP run control file, which (if present) will be searched for
2521 passwords as a last resort before prompting for one interactively.
2523 /var/run/fetchmail.pid
2524 lock file to help prevent concurrent runs (root mode, Linux systems).
2527 lock file to help prevent concurrent runs (root mode, systems without /var/run).
2530 If the FETCHMAILUSER variable is set, it is used as the name of the
2531 calling user (default local name) for purposes such as mailing error
2532 notifications. Otherwise, if either the LOGNAME or USER variable is
2533 correctly set (e.g. the corresponding UID matches the session user ID)
2534 then that name is used as the default local name. Otherwise
2535 \fBgetpwuid\fR(3) must be able to retrieve a password entry for the
2536 session ID (this elaborate logic is designed to handle the case of
2537 multiple names per userid gracefully).
2539 If the environment variable FETCHMAILHOME is set to a valid and
2540 existing directory name, fetchmail will read $FETCHMAILHOME/fetchmailrc
2541 (the dot is missing in this case), $FETCHMAILHOME/.fetchids and
2542 $FETCHMAILHOME/.fetchmail.pid rather than from the user's home
2543 directory. The .netrc file is always looked for in the the invoking
2544 user's home directory regardless of FETCHMAILHOME's setting.
2546 If the HOME_ETC variable is set, fetchmail will read
2547 $HOME_ETC/.fetchmailrc instead of ~/.fetchmailrc.
2549 If HOME_ETC and FETCHMAILHOME are set, HOME_ETC will be ignored.
2554 daemon is running as root, SIGUSR1 wakes it up from its sleep phase and
2555 forces a poll of all non-skipped servers. For compatibility reasons,
2556 SIGHUP can also be used in 6.3.X but may not be available in future
2561 is running in daemon mode as non-root, use SIGUSR1 to wake it (this is
2562 so SIGHUP due to logout can retain the default action of killing it).
2566 in foreground while a background fetchmail is running will do
2567 whichever of these is appropriate to wake it up.
2569 .SH BUGS AND KNOWN PROBLEMS
2571 Fetchmail cannot handle user names that contain blanks after a "@"
2572 character, for instance "demonstr@ti on". These are rather uncommon and
2573 only hurt when using UID-based \-\-keep setups, so the 6.3.X versions of
2574 fetchmail won't be fixed.
2576 Please check the \fBNEWS\fP file that shipped with fetchmail for more
2577 known bugs than those listed here.
2579 The assumptions that the DNS and in particular the checkalias options
2580 make are not often sustainable. For instance, it has become uncommon for
2581 an MX server to be a POP3 or IMAP server at the same time. Therefore the
2582 MX lookups may go away in a future release.
2584 The mda and plugin options interact badly. In order to collect error
2585 status from the MDA, fetchmail has to change its normal signal
2586 handling so that dead plugin processes don't get reaped until the end
2587 of the poll cycle. This can cause resource starvation if too many
2588 zombies accumulate. So either don't deliver to a MDA using plugins or
2589 risk being overrun by an army of undead.
2591 The \-\-interface option does not support IPv6 and it is doubtful if it
2592 ever will, since there is no portable way to query interface IPv6
2595 The RFC822 address parser used in multidrop mode chokes on some
2596 @-addresses that are technically legal but bizarre. Strange uses of
2597 quoting and embedded comments are likely to confuse it.
2599 In a message with multiple envelope headers, only the last one
2600 processed will be visible to fetchmail.
2602 Use of some of these protocols requires that the program send
2603 unencrypted passwords over the TCP/IP connection to the mailserver.
2604 This creates a risk that name/password pairs might be snaffled with a
2605 packet sniffer or more sophisticated monitoring software. Under Linux
2606 and FreeBSD, the \-\-interface option can be used to restrict polling to
2607 availability of a specific interface device with a specific local or
2608 remote IP address, but snooping is still possible if (a) either host
2609 has a network device that can be opened in promiscuous mode, or (b)
2610 the intervening network link can be tapped. We recommend the use of
2612 tunnelling to not only shroud your passwords but encrypt the entire
2615 Use of the %F or %T escapes in an mda option could open a security
2616 hole, because they pass text manipulable by an attacker to a shell
2617 command. Potential shell characters are replaced by '_' before
2618 execution. The hole is further reduced by the fact that fetchmail
2619 temporarily discards any suid privileges it may have while running the
2620 MDA. For maximum safety, however, don't use an mda command containing
2621 %F or %T when fetchmail is run from the root account itself.
2623 Fetchmail's method of sending bounces due to errors or spam-blocking and
2624 spam bounces requires that port 25 of localhost be available for sending
2629 while a background instance is running and break the syntax, the
2630 background instance will die silently. Unfortunately, it can't
2631 die noisily because we don't yet know whether syslog should be enabled.
2632 On some systems, fetchmail dies quietly even if there is no syntax
2633 error; this seems to have something to do with buggy terminal ioctl
2636 The \-f\~\- option (reading a configuration from stdin) is incompatible
2637 with the plugin option.
2639 The 'principal' option only handles Kerberos IV, not V.
2641 Interactively entered passwords are truncated after 63 characters. If
2642 you really need to use a longer password, you will have to use a
2645 A backslash as the last character of a configuration file will be
2646 flagged as a syntax error rather than ignored.
2648 Send comments, bug reports, gripes, and the like to the
2649 fetchmail\-devel list <fetchmail\-devel@lists.berlios.de>. An HTML FAQ is
2650 available at the fetchmail home page; surf to
2651 http://fetchmail.berlios.de/ or do a WWW search for pages with
2652 \&'fetchmail' in their titles.
2655 Fetchmail is currently maintained by Matthias Andree and Rob Funk with
2656 major assistance from Sunil Shetye (for code) and Rob MacGregor (for the
2659 Most of the code is from Eric S. Raymond <esr@snark.thyrsus.com>. Too
2660 many other people to name here have contributed code and patches.
2662 This program is descended from and replaces
2664 by Carl Harris <ceharris@mal.com>; the internals have become quite different,
2665 but some of its interface design is directly traceable to that
2668 This manual page has been improved by R.\ Hannes Beinert and H\['e]ctor
2672 mutt(1), elm(1), mail(1), sendmail(8), popd(8), imapd(8), netrc(5)
2674 The fetchmail home page: <http://fetchmail.berlios.de/>
2676 The maildrop home page: <http://www.courier-mta.org/maildrop/>
2677 .SH APPLICABLE STANDARDS
2679 Note that this list is just a collection of references and not a
2680 statement as to the actual protocol conformance or requirements in
2684 RFC 821, RFC 2821, RFC 1869, RFC 1652, RFC 1870, RFC 1983, RFC 1985,
2688 RFC 822, RFC 2822, RFC 1123, RFC 1892, RFC 1894.
2694 RFC 1081, RFC 1225, RFC 1460, RFC 1725, RFC 1734, RFC 1939, RFC 1957,
2698 RFC 1460, RFC 1725, RFC 1939.
2707 RFC 1730, RFC 1731, RFC 1732, RFC 2060, RFC 2061, RFC 2195, RFC 2177,
projects / ~andy / fetchmail / blob