2 .\" ** The above line should force tbl to be used as a preprocessor **
4 .\" Man page for fetchmail
6 .\" For license terms, see the file COPYING in this directory.
9 fetchmail \- fetch mail from a POP, IMAP, ETRN, or ODMR-capable server
12 \fBfetchmail\fR [\fIoption...\fR] [\fImailserver...\fR]
18 is a mail-retrieval and forwarding utility; it fetches mail from
19 remote mailservers and forwards it to your local (client) machine's
20 delivery system. You can then handle the retrieved mail using normal
21 mail user agents such as \fImutt\fR(1), \fIelm\fR(1) or \fIMail\fR(1).
22 The \fIfetchmail\fR utility can be run in a daemon mode to repeatedly
23 poll one or more systems at a specified interval.
27 program can gather mail from servers supporting any of the common
28 mail-retrieval protocols: POP2, POP3, IMAP2bis, IMAP4, and IMAP4rev1.
29 It can also use the ESMTP ETRN extension and ODMR. (The RFCs describing all
30 these protocols are listed at the end of this manual page.)
34 is primarily intended to be used over on-demand TCP/IP links (such as
35 SLIP or PPP connections), it may also be useful as a message transfer
36 agent for sites which refuse for security reasons to permit
37 (sender-initiated) SMTP transactions with sendmail.
41 is used with a POP or an IMAP server, it has two fundamental modes of
42 operation for each user account from which it retrieves mail:
43 \fIsingledrop\fR- and \fImultidrop\fR-mode. In singledrop-mode,
45 assumes that all messages in the user's account are intended for a single
46 recipient. An individual mail message will not be inspected for recipient
47 information, rather, the identity of the recipient will either default to
48 the local user currently executing \fIfetchmail\fR,
49 or else will need to be explicitly specified in the configuration file.
50 Singledrop-mode is used when the fetchmailrc configuration contains at
51 most a single local user specification for a given server account.
55 is not able to assume that there is only a single recipient, but rather
56 that the mail server account actually contains mail intended for any
57 number of different recipients. Therefore,
59 must attempt to deduce the proper "envelope recipient" from the mail
60 headers of each message. In this mode of operation
62 almost resembles an MTA, however it is important to note that neither
63 the POP nor IMAP protocols were intended for use in this fashion, and
64 hence envelope information is not directly available. Instead,
66 must resort to a process of informed guess-work in an attempt to
67 discover the true envelope recipient of a message. Even if this
68 information is present in the headers, the process can
69 be error-prone and is dependent upon the specific mail server used
70 for mail retrieval. Multidrop-mode is used when more than one local
71 user is specified for a particular server account in the configuration
72 file. Note that the forgoing discussion of singledrop- and
73 multidrop-modes does not apply to the ESMTP ETRN or ODMR retrieval
74 methods, since they are based upon the SMTP protocol which
75 specifically provides the envelope recipient to \fIfetchmail\fR.
77 As each message is retrieved \fIfetchmail\fR normally delivers it via SMTP to
78 port 25 on the machine it is running on (localhost), just as though it
79 were being passed in over a normal TCP/IP link. \fIfetchmail\fR provides
80 the SMTP server with an envelope recipient derived in the manner described
81 previously. The mail will then be
82 delivered locally via your system's MDA (Mail Delivery Agent, usually
83 \fIsendmail\fR(8) but your system may use a different one such
84 as \fIsmail\fR, \fImmdf\fR, \fIexim\fR, \fIpostfix\fR, or \fIqmail\fR). All the
85 delivery-control mechanisms (such as \fI.forward\fR files) normally
86 available through your system MDA and local delivery agents will
87 therefore work automatically.
89 If no port 25 listener is available, but your fetchmail configuration
90 was told about a reliable local MDA, it will use that MDA for local
95 is available, it will assist you in setting up and editing a
96 fetchmailrc configuration. It runs under the X window system and
97 requires that the language Python and the Tk toolkit be present on your
98 system. If you are first setting up fetchmail for single-user mode, it
99 is recommended that you use Novice mode. Expert mode provides complete
100 control of fetchmail configuration, including the multidrop features.
101 In either case, the `Autoprobe' button will tell you the most capable
102 protocol a given mailserver supports, and warn you of potential problems
105 .SH GENERAL OPERATION
108 is controlled by command-line options and a run control file,
109 .IR ~/.fetchmailrc\fR ,
110 the syntax of which we describe in a later section (this file is what
111 the \fIfetchmailconf\fR program edits). Command-line options override
115 Each server name that you specify following the options on the
116 command line will be queried. If you don't specify any servers
117 on the command line, each `poll' entry in your
119 file will be queried.
121 To facilitate the use of
123 in scripts and pipelines, it returns an appropriate exit code upon
124 termination -- see EXIT CODES below.
126 The following options modify the behavior of \fIfetchmail\fR. It is
127 seldom necessary to specify any of these once you have a
128 working \fI.fetchmailrc\fR file set up.
130 Almost all options have a corresponding keyword which can be used to
135 Some special options are not covered here, but are documented instead
136 in sections on AUTHENTICATION and DAEMON MODE which follow.
140 Displays the version information for your copy of
142 No mail fetch is performed.
143 Instead, for each server specified, all the option information
144 that would be computed if
146 were connecting to that server is displayed. Any non-printables in
147 passwords or other string names are shown as backslashed C-like
148 escape sequences. This option is useful for verifying that your
149 options are set the way you want them.
152 Return a status code to indicate whether there is mail waiting,
153 without actually fetching or deleting mail (see EXIT CODES below).
154 This option turns off daemon mode (in which it would be useless). It
155 doesn't play well with queries to multiple sites, and doesn't work
156 with ETRN or ODMR. It will return a false positive if you leave read but
157 undeleted mail in your server mailbox and your fetch protocol can't
158 tell kept messages from new ones. This means it will work with IMAP,
159 not work with POP2, and may occasionally flake out under POP3.
162 Silent mode. Suppresses all progress/status messages that are
163 normally echoed to standard output during a fetch (but does not
164 suppress actual error messages). The --verbose option overrides this.
167 Verbose mode. All control messages passed between
169 and the mailserver are echoed to stdout. Overrides --silent.
170 Doubling this option (-v -v) causes extra diagnostic information
176 Retrieve both old (seen) and new messages from the mailserver. The
177 default is to fetch only messages the server has not marked seen.
178 Under POP3, this option also forces the use of RETR rather than TOP.
179 Note that POP2 retrieval behaves as though --all is always on (see
180 RETRIEVAL FAILURE MODES below) and this option does not work with ETRN
185 Keep retrieved messages on the remote mailserver. Normally, messages
186 are deleted from the folder on the mailserver after they have been retrieved.
189 option causes retrieved messages to remain in your folder on the
190 mailserver. This option does not work with ETRN or ODMR.
194 Delete retrieved messages from the remote mailserver. This
195 option forces retrieved mail to be deleted. It may be useful if
196 you have specified a default of \fBkeep\fR in your
197 \&\fI.fetchmailrc\fR. This option is forced on with ETRN and ODMR.
200 POP3/IMAP only. Delete old (previously retrieved) messages from the
201 mailserver before retrieving new messages. This option does not work
202 with ETRN or ODMR. Warning: if your local MTA hangs and fetchmail is
203 aborted, the next time you run fetchmail, it will delete mail that was
204 never delivered to you. What you probably want is the default
205 setting: if you don't specify `-k', then fetchmail will automatically
206 delete messages after successful delivery.
207 .SS Protocol and Query Options
209 .B \-p <proto> | \-\-protocol <proto>
210 (Keyword: proto[col])
211 Specify the protocol to use when communicating with the remote
212 mailserver. If no protocol is specified, the default is AUTO.
214 may be one of the following:
217 Tries IMAP, POP3, and POP2 (skipping any of these for which support
218 has not been compiled in).
220 Post Office Protocol 2
222 Post Office Protocol 3
224 Use POP3 with old-fashioned MD5-challenge authentication.
226 Use POP3 with RPOP authentication.
228 Use POP3 with Kerberos V4 authentication on port 1109.
230 Use POP3 with Demon Internet's SDPS extensions.
232 IMAP2bis, IMAP4, or IMAP4rev1 (\fIfetchmail\fR autodetects their capabilities).
234 Use the ESMTP ETRN option.
236 Use the the On-Demand Mail Relay ESMTP profile.
239 All these alternatives work in basically the same way (communicating
240 with standard server daemons to fetch mail already delivered to a
241 mailbox on the server) except ETRN and ODMR. The ETRN mode
242 allows you to ask a compliant ESMTP server (such as BSD sendmail at
243 release 8.8.0 or higher) to immediately open a sender-SMTP connection
244 to your client machine and begin forwarding any items addressed to
245 your client machine in the server's queue of undelivered mail. The
246 ODMR mode requires an ODMR-capable server and works similarly to
247 ETRN, except that it does not require the client machine to have
252 Force UIDL use (effective only with POP3). Force client-side tracking
253 of `newness' of messages (UIDL stands for ``unique ID listing'' and is
254 described in RFC1939). Use with `keep' to use a mailbox as a baby
255 news drop for a group of users. The fact that seen messages are skipped
256 is logged, unless error logging is done through syslog while running in
257 daemon mode. Note that fetchmail may automatically enable this option
258 depending on upstream server capabilities. Note also that this option
259 may be removed and forced enabled in a future fetchmail version.
262 .B \-P <portnumber> | \-\-port <portnumber>
264 The port option permits you to specify a TCP/IP port to connect on.
265 This option will seldom be necessary as all the supported protocols have
266 well-established default port numbers.
268 .B \-\-principal <principal>
270 The principal option permits you to specify a service principal for
271 mutual authentication. This is applicable to POP3 or IMAP with Kerberos
274 .B \-t <seconds> | -\-timeout <seconds>
276 The timeout option allows you to set a server-nonresponse
277 timeout in seconds. If a mailserver does not send a greeting message
278 or respond to commands for the given number of seconds,
279 \fIfetchmail\fR will hang up on it. Without such a timeout
280 \fIfetchmail\fR might hang up indefinitely trying to fetch mail from a
281 down host. This would be particularly annoying for a \fIfetchmail\fR
282 running in background. There is a default timeout which fetchmail -V
283 will report. If a given connection receives too many timeouts in
284 succession, fetchmail will consider it wedged and stop retrying,
285 the calling user will be notified by email if this happens.
287 .B \-\-plugin <command>
288 (Keyword: plugin) The plugin option allows you to use an external
289 program to establish the TCP connection. This is useful if you want
290 to use socks, SSL, ssh, or need some special firewalling setup. The
291 program will be looked up in $PATH and can optionally be passed the
292 hostname and port as arguments using "%h" and "%p" respectively (note
293 that the interpolation logic is rather primitive, and these token must
294 be bounded by whitespace or beginning of string or end of string).
295 Fetchmail will write to the plugin's stdin and read from the plugin's
298 .B \-\-plugout <command>
300 Identical to the plugin option above, but this one is used for the SMTP
301 connections (which will probably not need it, so it has been separated
304 .B \-r <name> | \-\-folder <name>
306 Causes a specified non-default mail folder on the mailserver (or
307 comma-separated list of folders) to be retrieved. The syntax of the
308 folder name is server-dependent. This option is not available under
312 (Keyword: tracepolls)
313 Tell fetchmail to poll trace information in the form `polling %s
314 account %s' to the Received line it generates, where the %s parts are
315 replaced by the user's remote name and the poll label (the Received
316 header also normally includes the server's true name). This can be
317 used to facilitate mail filtering based on the account it is being
322 Causes the connection to the mail server to be encrypted via SSL. Connect
323 to the server using the specified base protocol over a connection secured
324 by SSL. SSL support must be present at the server. If no port is
325 specified, the connection is attempted to the well known port of the SSL
326 version of the base protocol. This is generally a different port than the
327 port used by the base protocol. For IMAP, this is port 143 for the clear
328 protocol and port 993 for the SSL secured protocol.
330 .B \-\-sslcert <name>
332 Specifies the file name of the client side public SSL certificate. Some
333 SSL encrypted servers may require client side keys and certificates for
334 authentication. In most cases, this is optional. This specifies
335 the location of the public key certificate to be presented to the server
336 at the time the SSL session is established. It is not required (but may
337 be provided) if the server does not require it. Some servers may
338 require it, some servers may request it but not require it, and some
339 servers may not request it at all. It may be the same file
340 as the private key (combined key and certificate file) but this is not
345 Specifies the file name of the client side private SSL key. Some SSL
346 encrypted servers may require client side keys and certificates for
347 authentication. In most cases, this is optional. This specifies
348 the location of the private key used to sign transactions with the server
349 at the time the SSL session is established. It is not required (but may
350 be provided) if the server does not require it. Some servers may
351 require it, some servers may request it but not require it, and some
352 servers may not request it at all. It may be the same file
353 as the public key (combined key and certificate file) but this is not
354 recommended. If a password is required to unlock the key, it will be
355 prompted for at the time just prior to establishing the session to the
356 server. This can cause some complications in daemon mode.
358 .B \-\-sslproto <name>
360 Forces an SSL protocol. Possible values are \&`\fBssl2\fR', `\fBssl3\fR' and
361 `\fBtls1\fR'. Try this if the default handshake does not work for your server.
365 Causes fetchmail to strictly check the server certificate against a set of
366 local trusted certificates (see the \fBsslcertpath\fR option). If the server
367 certificate is not signed by one of the trusted ones (directly or indirectly),
368 the SSL connection will fail. This checking should prevent man-in-the-middle
369 attacks against the SSL connection. Note that CRLs are seemingly not currently
370 supported by OpenSSL in certificate verification! Your system clock should
371 be reasonably accurate when using this option!
373 .B \-\-sslcertpath <directory>
374 (Keyword: sslcertpath)
375 Sets the directory fetchmail uses to look up local certificates. The default
376 is your OpenSSL default one. The directory must be hashed as OpenSSL expects
377 it - every time you add or modify a certificate in the directory, you need
378 to use the \fBc_rehash\fR tool (which comes with OpenSSL in the tools/
381 .B \-\-sslfingerprint <fingerprint>
382 (Keyword: sslfingerprint)
383 Specify the fingerprint of the server key (an MD5 hash of the key) in
384 hexadecimal notation with colons separating groups of two digits. The letter
385 hex digits must be in upper case. This is the default format OpenSSL uses,
386 and the one fetchmail uses to report the fingerprint when an SSL connection
387 is established. When this is specified, fetchmail will compare the server key
388 fingerprint with the given one, and the connection will fail if they do not
389 match. This can be used to prevent man-in-the-middle attacks.
390 .SS Delivery Control Options
392 .B \-S <hosts> | \-\-smtphost <hosts>
393 (Keyword: smtp[host])
394 Specify a hunt list of hosts to forward mail to (one or more
395 hostnames, comma-separated). Hosts are tried in list order; the first
396 one that is up becomes the forwarding target for the current run.
397 Normally, `localhost' is added to the end of the list as an invisible
398 default. However, when using Kerberos authentication, the FQDN of the
399 machine running fetchmail is added to the end of the list as an
400 invisible default. Each hostname may have a port number following the
401 host name. The port number is separated from the host name by a
402 slash; the default port is 25 (or ``smtp'' under IPv6). If you
403 specify an absolute path name (beginning with a /), it will be
404 interpreted as the name of a UNIX socket accepting LMTP connections
405 (such as is supported by the Cyrus IMAP daemon) Example:
408 --smtphost server1,server2/2525,server3,/var/imap/socket/lmtp
411 This option can be used with ODMR, and will make fetchmail a relay
412 between the ODMR server and SMTP or LMTP receiver.
414 .B \-\-fetchdomains <hosts>
415 (Keyword: fetchdomains)
416 In ETRN or ODMR mode, this option specifies the list of domains the
417 server should ship mail for once the connection is turned around. The
418 default is the FQDN of the machine running
421 .B \-D <domain> | \-\-smtpaddress <domain>
422 (Keyword: smtpaddress) Specify the domain to be appended to addresses
423 in RCPT TO lines shipped to SMTP. The name of the SMTP server (as
424 specified by --smtphost, or defaulted to "localhost") is used when
425 this is not specified.
427 .B \-\-smtpname <user@domain>
429 Specify the domain and user to be put in RCPT TO lines shipped to SMTP.
430 The default user is the current local user.
432 .B \-Z <nnn> | \-\-antispam <nnn[, nnn]...>
434 Specifies the list of numeric SMTP errors that are to be interpreted
435 as a spam-block response from the listener. A value of -1 disables
436 this option. For the command-line option, the list values should
439 .B \-m <command> | \-\-mda <command>
440 (Keyword: mda) You can force mail to be passed to an MDA directly
441 (rather than forwarded to port 25) with the --mda or -m option. To
442 avoid losing mail, use this option only with MDAs like procmail or
443 sendmail that return a nonzero status on disk-full and other
444 resource-exhaustion errors; the nonzero status tells fetchmail that
445 delivery failed and prevents the message from being deleted off the
446 server. If \fIfetchmail\fR is running as root, it sets its user id to
447 that of the target user while delivering mail through an MDA. Some
448 possible MDAs are "/usr/sbin/sendmail -i -f %F %T", "/usr/bin/deliver"
449 and "/usr/bin/procmail -d %T" (but the latter is usually redundant as
450 it's what SMTP listeners normally forward to). Local delivery
451 addresses will be inserted into the MDA command wherever you place a
452 %T; the mail message's From address will be inserted where you place
453 an %F. In both cases the addresses are enclosed in single quotes ('),
454 after removing any single quotes they may contain, before the MDA
455 command is passed to the shell. Do \fInot\fR use an MDA invocation
456 like "sendmail -i -t" that dispatches on the contents of To/Cc/Bcc, it
457 will create mail loops and bring the just wrath of many postmasters
458 down upon your head. Also, do \fInot\fR try to combine multidrop
459 mode with an MDA such as procmail that can only accept one addressee;
464 Cause delivery via LMTP (Local Mail Transfer Protocol). A service
465 port \fImust\fR be explicitly specified (with a slash suffix) on each
466 host in the smtphost hunt list if this option is selected; the
467 default port 25 will (in accordance with RFC 2033) not be accepted.
469 .B \-\-bsmtp <filename>
471 Append fetched mail to a BSMTP file. This simply contains the SMTP
472 commands that would normally be generated by fetchmail when passing
473 mail to an SMTP listener daemon. An argument of `-' causes the mail
474 to be written to standard output. Note that fetchmail's
475 reconstruction of MAIL FROM and RCPT TO lines is not guaranteed
476 correct; the caveats discussed under THE USE AND ABUSE OF MULTIDROP
477 MAILBOXES below apply.
478 .SS Resource Limit Control Options
480 .B \-l <maxbytes> | \-\-limit <maxbytes>
481 (Keyword: limit) Takes a maximum octet size argument. Messages larger
482 than this size will not be fetched and will be left on the server (in
483 foreground sessions, the progress messages will note that they are
484 "oversized"). If the fetch protocol permits (in particular, under
485 IMAP or POP3 without the fetchall option) the message will not be
486 marked seen. An explicit --limit of 0 overrides any limits set in your
487 run control file. This option is intended for those needing to
488 strictly control fetch time due to expensive and variable phone rates.
489 Combined with --flush, it can be used to delete oversized messages
490 waiting on a server. In daemon mode, oversize notifications are
491 mailed to the calling user (see the --warnings option). This option
492 does not work with ETRN or ODMR.
494 .B \-w <interval> | \-\-warnings <interval>
496 Takes an interval in seconds. When you call
498 with a `limit' option in daemon mode, this controls the interval at
499 which warnings about oversized messages are mailed to the calling user
500 (or the user specified by the `postmaster' option). One such
501 notification is always mailed at the end of the the first poll that
502 the oversized message is detected. Thereafter, renotification is
503 suppressed until after the warning interval elapses (it will take
504 place at the end of the first following poll).
506 .B \-b <count> | \-\-batchlimit <count>
507 (Keyword: batchlimit)
508 Specify the maximum number of messages that will be shipped to an SMTP
509 listener before the connection is deliberately torn down and rebuilt
510 (defaults to 0, meaning no limit). An explicit --batchlimit of 0
511 overrides any limits set in your run control file. While
512 \fBsendmail\fR(8) normally initiates delivery of a message immediately
513 after receiving the message terminator, some SMTP listeners are not so
514 prompt. MTAs like \fIsmail\fR(8) may wait till the
515 delivery socket is shut down to deliver. This may produce annoying
516 delays when \fIfetchmail\fR is processing very large batches. Setting
517 the batch limit to some nonzero size will prevent these delays. This
518 option does not work with ETRN or ODMR.
520 .B \-B <number> | \-\-fetchlimit <number>
521 (Keyword: fetchlimit)
522 Limit the number of messages accepted from a given server in a single
523 poll. By default there is no limit. An explicit --fetchlimit of 0
524 overrides any limits set in your run control file.
525 This option does not work with ETRN or ODMR.
527 .B \-\-fetchsizelimit <number>
528 (Keyword: fetchsizelimit)
529 Limit the number of sizes of messages accepted from a given server in
530 a single transaction. This option is useful in reducing the delay in
531 downloading the first mail when there are too many mails in the
532 mailbox. By default, the limit is 100. If set to 0, sizes of all
533 messages are downloaded at the start.
534 This option does not work with ETRN or ODMR. For POP3, the only valid
537 .B \-\-fastuidl <number>
539 Do a binary instead of linear search for the first unseen UID. Binary
540 search avoids downloading the UIDs of all mails. This saves time
541 (especially in daemon mode) where downloading the same set of UIDs in
542 each poll is a waste of bandwidth. The number `n' indicates how rarely
543 a linear search should be done. In daemon mode, linear search is used
544 once followed by binary searches in `n-1' polls if `n' is greater than
545 1; binary search is always used if `n' is 1; linear search is always
546 used if `n' is 0. In non-daemon mode, binary search is used if `n' is
547 1; otherwise linear search is used.
548 This option works with POP3 only.
550 .B \-e <count> | \-\-expunge <count>
552 Arrange for deletions to be made final after a given number of
553 messages. Under POP2 or POP3, fetchmail cannot make deletions final
554 without sending QUIT and ending the session -- with this option on,
555 fetchmail will break a long mail retrieval session into multiple
556 sub-sessions, sending QUIT after each sub-session. This is a good
557 defense against line drops on POP3 servers that do not do the
558 equivalent of a QUIT on hangup. Under IMAP,
560 normally issues an EXPUNGE command after each deletion in order to
561 force the deletion to be done immediately. This is safest when your
562 connection to the server is flaky and expensive, as it avoids
563 resending duplicate mail after a line hit. However, on large
564 mailboxes the overhead of re-indexing after every message can slam the
565 server pretty hard, so if your connection is reliable it is good to do
566 expunges less frequently. Also note that some servers enforce a delay
567 of a few seconds after each quit, so fetchmail may not be able to get
568 back in immediately after an expunge -- you may see "lock busy" errors
569 if this happens. If you specify this option to an integer N,
572 to only issue expunges on every Nth delete. An argument of zero
573 suppresses expunges entirely (so no expunges at all will be done until
574 the end of run). This option does not work with ETRN or ODMR.
575 .SS Authentication Options
577 .B \-u <name> | \-\-username <name>
578 (Keyword: user[name])
579 Specifies the user identification to be used when logging in to the mailserver.
580 The appropriate user identification is both server and user-dependent.
581 The default is your login name on the client machine that is running
583 See USER AUTHENTICATION below for a complete description.
585 .B \-I <specification> | \-\-interface <specification>
587 Require that a specific interface device be up and have a specific local
588 or remote IP address (or range) before polling. Frequently
590 is used over a transient point-to-point TCP/IP link established directly
591 to a mailserver via SLIP or PPP. That is a relatively secure channel.
592 But when other TCP/IP routes to the mailserver exist (e.g. when the link
593 is connected to an alternate ISP), your username and password may be
594 vulnerable to snooping (especially when daemon mode automatically polls
595 for mail, shipping a clear password over the net at predictable
596 intervals). The --interface option may be used to prevent this. When
597 the specified link is not up or is not connected to a matching IP
598 address, polling will be skipped. The format is:
601 interface/iii.iii.iii.iii/mmm.mmm.mmm.mmm
604 The field before the first slash is the interface name (i.e. sl0, ppp0
605 etc.). The field before the second slash is the acceptable IP address.
606 The field after the second slash is a mask which specifies a range of
607 IP addresses to accept. If no mask is present 255.255.255.255 is
608 assumed (i.e. an exact match). This option is currently only supported
609 under Linux and FreeBSD. Please see the
611 section for below for FreeBSD specific information.
613 .B \-M <interface> | --monitor <interface>
615 Daemon mode can cause transient links which are automatically taken down
616 after a period of inactivity (e.g. PPP links) to remain up
617 indefinitely. This option identifies a system TCP/IP interface to be
618 monitored for activity. After each poll interval, if the link is up but
619 no other activity has occurred on the link, then the poll will be
620 skipped. However, when fetchmail is woken up by a signal, the
621 monitor check is skipped and the poll goes through unconditionally.
622 This option is currently only supported under Linux and FreeBSD.
627 options to work for non root users under FreeBSD, the fetchmail binary
628 must be installed SGID kmem. This would be a security hole, but
629 fetchmail runs with the effective GID set to that of the kmem group
631 when interface data is being collected.
634 (Keyword: auth[enticate])
635 This option permits you to specify an authentication type (see USER
636 AUTHENTICATION below for details). The possible values are \fBany\fR,
637 \&`\fBpassword\fR', `\fBkerberos_v5\fR' and `\fBkerberos\fR' (or, for
638 excruciating exactness, `\fBkerberos_v4\fR'), \fRgssapi\fR,
639 \fIcram-md5\fR, \fIotp\fR, \fIntlm\fR, and \fBssh\fR. When \fBany\fR (the
640 default) is specified, fetchmail tries first methods that don't
641 require a password (GSSAPI, KERBEROS_IV); then it looks for methods
642 that mask your password (CRAM-MD5, X-OTP, NTLM); and only if the server
643 doesn't support any of those will it ship your password en clair.
644 Other values may be used to force various authentication methods
645 (\fBssh\fR suppresses authentication). Any value other than
646 \fIpassword\fR, \fIcram-md5\fR, \fIntlm\fR or \fIotp\fR suppresses fetchmail's
647 normal inquiry for a password. Specify \fIssh\fR when you are using
648 an end-to-end secure connection such as an ssh tunnel; specify
649 \fRgssapi\fR or \fBkerberos_v4\fR if you are using a protocol variant
650 that employs GSSAPI or K4. Choosing KPOP protocol automatically
651 selects Kerberos authentication. This option does not work with ETRN.
652 .SS Miscellaneous Options
654 .B \-f <pathname> | \-\-fetchmailrc <pathname>
655 Specify a non-default name for the
657 run control file. The pathname argument must be either "-" (a single
658 dash, meaning to read the configuration from standard input) or a
659 filename. Unless the --version option is also on, a named file
660 argument must have permissions no more open than 0600 (u=rw,g=,o=) or
663 .B \-i <pathname> | \-\-idfile <pathname>
665 Specify an alternate name for the .fetchids file used to save POP3
668 .B \-n | \-\-norewrite
669 (Keyword: no rewrite)
672 edits RFC-822 address headers (To, From, Cc, Bcc, and Reply-To) in
673 fetched mail so that any mail IDs local to the server are expanded to
674 full addresses (@ and the mailserver hostname are appended). This enables
675 replies on the client to get addressed correctly (otherwise your
676 mailer might think they should be addressed to local users on the
677 client machine!). This option disables the rewrite. (This option is
678 provided to pacify people who are paranoid about having an MTA edit
679 mail headers and want to know they can prevent it, but it is generally
680 not a good idea to actually turn off rewrite.)
681 When using ETRN or ODMR, the rewrite option is ineffective.
683 .B \-E <line> | \-\-envelope <line>
684 (Keyword: envelope; Multidrop only)
685 This option changes the header
687 assumes will carry a copy of the mail's envelope address. Normally
688 this is `X-Envelope-To' but as this header is not standard, practice
689 varies. See the discussion of multidrop address handling below. As a
690 special case, `envelope "Received"' enables parsing of sendmail-style
691 Received lines. This is the default, and it should not be necessary
692 unless you have globally disabled Received parsing with `no envelope'
693 in the \fI.fetchmailrc\fR file.
695 .B \-Q <prefix> | \-\-qvirtual <prefix>
696 (Keyword: qvirtual; Multidrop only)
697 The string prefix assigned to this option will be removed from the user
698 name found in the header specified with the \fIenvelope\fR option
699 (\fIbefore\fR doing multidrop name mapping or localdomain checking,
700 if either is applicable). This option is useful if you are using
702 to collect the mail for an entire domain and your ISP (or your mail
703 redirection provider) is using qmail.
704 One of the basic features of qmail is the
708 message header. Whenever qmail delivers a message to a local mailbox
709 it puts the username and hostname of the envelope recipient on this
710 line. The major reason for this is to prevent mail loops. To set up
711 qmail to batch mail for a disconnected site the ISP-mailhost will have
712 normally put that site in its `Virtualhosts' control file so it will
713 add a prefix to all mail addresses for this site. This results in mail
714 .\" The \&@\& tries to stop HTML converters from making a mailto URL here.
715 sent to 'username\&@\&userhost.userdom.dom.com' having a
716 \&`Delivered-To:' line of the form:
718 Delivered-To: mbox-userstr-username\&@\&userhost.userdom.dom.com
720 The ISP can make the 'mbox-userstr-' prefix anything they choose
721 but a string matching the user host name is likely.
722 By using the option `envelope Delivered-To:' you can make fetchmail reliably
723 identify the original envelope recipient, but you have to strip the
724 `mbox-userstr-' prefix to deliver to the correct user.
725 This is what this option is for.
730 file, interpret any command-line options specified, and dump a
731 configuration report to standard output. The configuration report is
732 a data structure assignment in the language Python. This option
733 is meant to be used with an interactive
739 .SH USER AUTHENTICATION AND ENCRYPTION
740 All modes except ETRN require authentication of the client to the server.
741 Normal user authentication in
743 is very much like the authentication mechanism of
745 The correct user-id and password depend upon the underlying security
746 system at the mailserver.
748 If the mailserver is a Unix machine on which you have an ordinary user
749 account, your regular login name and password are used with
751 If you use the same login name on both the server and the client machines,
752 you needn't worry about specifying a user-id with the
754 option \-\- the default behavior is to use your login name on the
755 client machine as the user-id on the server machine. If you use a
756 different login name on the server machine, specify that login name
759 option. e.g. if your login name is 'jsmith' on a machine named 'mailgrunt',
764 fetchmail -u jsmith mailgrunt
766 The default behavior of
768 is to prompt you for your mailserver password before the connection is
769 established. This is the safest way to use
771 and ensures that your password will not be compromised. You may also specify
772 your password in your
774 file. This is convenient when using
776 in daemon mode or with scripts.
778 If you do not specify a password, and
780 cannot extract one from your
782 file, it will look for a
784 file in your home directory before requesting one interactively; if an
785 entry matching the mailserver is found in that file, the password will
786 be used. Fetchmail first looks for a match on poll name; if it finds none,
787 it checks for a match on via name. See the
789 man page for details of the syntax of the
791 file. (This feature may allow you to avoid duplicating password
792 information in more than one file.)
794 On mailservers that do not provide ordinary user accounts, your user-id and
795 password are usually assigned by the server administrator when you apply for
796 a mailbox on the server. Contact your server administrator if you don't know
797 the correct user-id and password for your mailbox account.
799 Early versions of POP3 (RFC1081, RFC1225) supported a crude form of
800 independent authentication using the
802 file on the mailserver side. Under this RPOP variant, a fixed
803 per-user ID equivalent to a password was sent in clear over a link to
804 a reserved port, with the command RPOP rather than PASS to alert the
805 server that it should do special checking. RPOP is supported
808 (you can specify `protocol RPOP' to have the program send `RPOP'
809 rather than `PASS') but its use is strongly discouraged. This
810 facility was vulnerable to spoofing and was withdrawn in RFC1460.
812 RFC1460 introduced APOP authentication. In this variant of POP3,
813 you register an APOP password on your server host (the program
814 to do this with on the server is probably called \fIpopauth\fR(8)). You
815 put the same password in your
819 logs in, it sends a cryptographically secure hash of your password and
820 the server greeting time to the server, which can verify it by
821 checking its authorization database.
823 If your \fIfetchmail\fR was built with Kerberos support and you specify
824 Kerberos authentication (either with --auth or the \fI.fetchmailrc\fR
825 option \fBauthenticate kerberos_v4\fR) it will try to get a Kerberos
826 ticket from the mailserver at the start of each query. Note: if
827 either the pollname or via name is `hesiod', fetchmail will try to use
828 Hesiod to look up the mailserver.
830 If you use POP3 or IMAP with GSSAPI authentication, \fIfetchmail\fR will
831 expect the server to have RFC1731- or RFC1734-conformant GSSAPI
832 capability, and will use it. Currently this has only been tested over
833 Kerberos V, so you're expected to already have a ticket-granting
834 ticket. You may pass a username different from your principal name
835 using the standard \fB--user\fR command or by the \fI.fetchmailrc\fR
838 If your IMAP daemon returns the PREAUTH response in its greeting line,
839 fetchmail will notice this and skip the normal authentication step.
840 This can be useful, e.g. if you start imapd explicitly using ssh.
841 In this case you can declare the authentication value `ssh' on that
842 site entry to stop \fI.fetchmail\fR from asking you for a password
845 If you are using POP3, and the server issues a one-time-password
846 challenge conforming to RFC1938, \fIfetchmail\fR will use your
847 password as a pass phrase to generate the required response. This
848 avoids sending secrets over the net unencrypted.
850 Compuserve's RPA authentication (similar to APOP) is supported. If you
851 compile in the support, \fIfetchmail\fR will try to perform an RPA pass-phrase
852 authentication instead of sending over the password en clair if it
853 detects "@compuserve.com" in the hostname.
855 If you are using IMAP, Microsoft's NTLM authentication (used by Microsoft
856 Exchange) is supported. If you compile in the support, \fIfetchmail\fR
857 will try to perform an NTLM authentication (instead of sending over the
858 password en clair) whenever the server returns AUTH=NTLM in its
859 capability response. Specify a user option value that looks like
860 `user@domain': the part to the left of the @ will be passed as the
861 username and the part to the right as the NTLM domain.
863 If you are using IPsec, the -T (--netsec) option can be used to pass
864 an IP security request to be used when outgoing IP connections are
865 initialized. You can also do this using the `netsec' server option
866 in the .fetchmailrc file. In either case, the option value is a
867 string in the format accepted by the net_security_strtorequest()
868 function of the inet6_apps library.
870 You can access SSL encrypted services by specifying the --ssl option.
871 You can also do this using the "ssl" server option in the .fetchmailrc
872 file. With SSL encryption enabled, queries are initiated over a connection
873 after negotiating an SSL session. Some services, such as POP3 and IMAP,
874 have different well known ports defined for the SSL encrypted services.
875 The encrypted ports will be selected automatically when SSL is enabled and
876 no explicit port is specified.
878 When connecting to an SSL encrypted server, the server presents a certificate
879 to the client for validation. The certificate is checked to verify that
880 the common name in the certificate matches the name of the server being
881 contacted and that the effective and expiration dates in the certificate
882 indicate that it is currently valid. If any of these checks fail, a warning
883 message is printed, but the connection continues. The server certificate
884 does not need to be signed by any specific Certifying Authority and may
885 be a "self-signed" certificate.
887 Some SSL encrypted servers may request a client side certificate. A client
888 side public SSL certificate and private SSL key may be specified. If
889 requested by the server, the client certificate is sent to the server for
890 validation. Some servers may require a valid client certificate and may
891 refuse connections if a certificate is not provided or if the certificate
892 is not valid. Some servers may require client side certificates be signed
893 by a recognized Certifying Authority. The format for the key files and
894 the certificate files is that required by the underlying SSL libraries
895 (OpenSSL in the general case).
897 A word of care about the use of SSL: While above mentioned
898 setup with self-signed server certificates retrieved over the wires
899 can protect you from a passive eavesdropper it doesn't help against an
900 active attacker. It's clearly an improvement over sending the
901 passwords in clear but you should be aware that a man-in-the-middle
902 attack is trivially possible (in particular with tools such as dsniff,
903 http://www.monkey.org/~dugsong/dsniff/). Use of an ssh tunnel (see
904 below for some examples) is preferable if you care seriously about the
905 security of your mailbox.
908 also supports authentication to the ESMTP server on the client side
909 according to RFC 2554. You can specify a name/password pair to be
910 used with the keywords `esmtpname' and `esmtppassword'; the former
911 defaults to the username of the calling user.
915 .B \-\-daemon <interval>
920 in daemon mode. You must specify a numeric argument which is a
921 polling interval in seconds.
925 puts itself in background and runs forever, querying each specified
926 host and then sleeping for the given polling interval.
932 will, therefore, poll all the hosts described in your
934 file (except those explicitly excluded with the `skip' verb) once
935 every fifteen minutes.
937 It is possible to set a polling interval
940 file by saying `set daemon <interval>', where <interval> is an
941 integer number of seconds. If you do this, fetchmail will always
942 start in daemon mode unless you override it with the command-line
943 option --daemon 0 or -d0.
945 Only one daemon process is permitted per user; in daemon mode,
947 makes a per-user lockfile to guarantee this.
949 Normally, calling fetchmail with a daemon in the background sends a
950 wake-up signal to the daemon, forcing it to poll mailservers
951 immediately. (The wake-up signal is SIGHUP if fetchmail is running as
952 root, SIGUSR1 otherwise.) The wake-up action also clears any `wedged'
953 flags indicating that connections have wedged due to failed
954 authentication or multiple timeouts.
958 will kill a running daemon process instead of waking it up (if there
961 notifies you). If the --quit option is the only command-line option,
962 that's all there is to it.
964 The quit option may also be mixed with other command-line options; its
965 effect is to kill any running daemon before doing what the other
966 options specify in combination with the fetchmailrc file.
971 .B \-\-logfile <filename>
972 option (keyword: set logfile) allows you to redirect status messages
973 emitted while detached into a specified logfile (follow the
974 option with the logfile name). The logfile is opened for append, so
975 previous messages aren't deleted. This is primarily useful for
976 debugging configurations.
980 option (keyword: set syslog) allows you to redirect status and error
981 messages emitted to the
983 system daemon if available.
984 Messages are logged with an id of \fBfetchmail\fR, the facility \fBLOG_MAIL\fR,
985 and priorities \fBLOG_ERR\fR, \fBLOG_ALERT\fR or \fBLOG_INFO\fR.
986 This option is intended for logging status and error messages which
987 indicate the status of the daemon and the results while fetching mail
989 Error messages for command line options and parsing the \fI.fetchmailrc\fR
990 file are still written to stderr, or to the specified log file.
993 option turns off use of
995 assuming it's turned on in the
1000 .B \-\-logfile <file>
1005 or --nodetach option suppresses backgrounding and detachment of the
1006 daemon process from its control terminal. This is useful
1007 for debugging or when fetchmail runs as the child of a supervisor
1012 Note that this also causes the logfile option to be
1013 ignored (though perhaps it shouldn't).
1015 Note that while running in daemon mode polling a POP2 or IMAP2bis server,
1016 transient errors (such as DNS failures or sendmail delivery refusals)
1017 may force the fetchall option on for the duration of the next polling
1018 cycle. This is a robustness feature. It means that if a message is
1019 fetched (and thus marked seen by the mailserver) but not delivered
1020 locally due to some transient error, it will be re-fetched during the
1021 next poll cycle. (The IMAP logic doesn't delete messages until
1022 they're delivered, so this problem does not arise.)
1024 If you touch or change the
1026 file while fetchmail is running in daemon mode, this will be detected
1027 at the beginning of the next poll cycle. When a changed
1029 is detected, fetchmail rereads it and restarts from scratch (using
1030 exec(2); no state information is retained in the new instance). Note also
1031 that if you break the
1033 file's syntax, the new instance will softly and silently vanish away
1036 .SH ADMINISTRATIVE OPTIONS
1039 .B \-\-postmaster <name>
1040 option (keyword: set postmaster) specifies the last-resort username to
1041 which multidrop mail is to be forwarded if no matching local recipient
1042 can be found. Normally this is just the user who invoked
1044 If the invoking user is root, then the default of this option is
1045 the user `postmaster'. Setting postmaster to the empty string causes
1046 such mail to be discarded.
1050 option suppresses the normal action of bouncing errors back to the
1051 sender in an RFC1894-conformant error message. If nobounce is on, the
1052 message will go to the postmaster instead.
1056 option (keyword: set invisible) tries to make fetchmail invisible.
1057 Normally, fetchmail behaves like any other MTA would -- it generates a
1058 Received header into each message describing its place in the chain of
1059 transmission, and tells the MTA it forwards to that the mail came from
1060 the machine fetchmail itself is running on. If the invisible option
1061 is on, the Received header is suppressed and fetchmail tries to spoof
1062 the MTA it forwards to into thinking it came directly from the
1067 option (keyword: set showdots) forces fetchmail to show progress dots
1068 even if the current tty is not stdout (for example logfiles).
1069 Starting with fetchmail version 5.3.0,
1070 progress dots are only shown on stdout by default.
1074 option, you can ask fetchmail to add information to the Received
1075 header on the form "polling {label} account {user}", where {label} is
1076 the account label (from the specified rcfile, normally ~/.fetchmailrc)
1077 and {user} is the username which is used to log on to the mail
1078 server. This header can be used to make filtering email where no
1079 useful header information is available and you want mail from
1080 different accounts sorted into different mailboxes (this could, for
1081 example, occur if you have an account on the same server running a
1082 mailing list, and are subscribed to the list using that account). The
1083 default is not adding any such header. In
1085 this is called `tracepolls'.
1087 .SH RETRIEVAL FAILURE MODES
1088 The protocols \fIfetchmail\fR uses to talk to mailservers are next to
1089 bulletproof. In normal operation forwarding to port 25, no message is
1090 ever deleted (or even marked for deletion) on the host until the SMTP
1091 listener on the client side has acknowledged to \fIfetchmail\fR that
1092 the message has been either accepted for delivery or rejected due to a
1095 When forwarding to an MDA, however, there is more possibility
1096 of error. Some MDAs are `safe' and reliably return a nonzero status
1097 on any delivery error, even one due to temporary resource limits.
1100 program is like this; so are most programs designed as mail transport
1105 These programs give back a reliable positive acknowledgement and
1106 can be used with the mda option with no risk of mail loss. Unsafe
1107 MDAs, though, may return 0 even on delivery failure. If this
1108 happens, you will lose mail.
1110 The normal mode of \fIfetchmail\fR is to try to download only `new'
1111 messages, leaving untouched (and undeleted) messages you have already
1112 read directly on the server (or fetched with a previous \fIfetchmail
1113 --keep\fR). But you may find that messages you've already read on the
1114 server are being fetched (and deleted) even when you don't specify
1115 --all. There are several reasons this can happen.
1117 One could be that you're using POP2. The POP2 protocol includes no
1118 representation of `new' or `old' state in messages, so \fIfetchmail\fR
1119 must treat all messages as new all the time. But POP2 is obsolete, so
1122 A potential POP3 problem might be servers that insert messages
1123 in the middle of mailboxes (some VMS implementations of mail are
1124 rumored to do this). The \fIfetchmail\fR code assumes that new
1125 messages are appended to the end of the mailbox; when this is not true
1126 it may treat some old messages as new and vice versa. Using UIDL might
1127 fix this, otherwise, consider switching to IMAP.
1129 Yet another POP3 problem is that if they can't make tempfiles in the
1130 user's home directory, some POP3 servers will hand back an
1131 undocumented response that causes fetchmail to spuriously report "No
1134 The IMAP code uses the presence or absence of the server flag \eSeen
1135 to decide whether or not a message is new. This isn't the right thing
1136 to do, fetchmail should check the UIDVALIDITY and use UID, but it
1137 doesn't do that yet. Under Unix, it counts on your IMAP server to notice
1138 the BSD-style Status flags set by mail user agents and set the \eSeen
1139 flag from them when appropriate. All Unix IMAP servers we know of do
1140 this, though it's not specified by the IMAP RFCs. If you ever trip over
1141 a server that doesn't, the symptom will be that messages you have
1142 already read on your host will look new to the server. In this
1143 (unlikely) case, only messages you fetched with \fIfetchmail --keep\fR
1144 will be both undeleted and marked old.
1146 In ETRN and ODMR modes, \fIfetchmail\fR does not actually retrieve messages;
1147 instead, it asks the server's SMTP listener to start a queue flush
1148 to the client via SMTP. Therefore it sends only undelivered messages.
1151 Many SMTP listeners allow administrators to set up `spam filters' that
1152 block unsolicited email from specified domains. A MAIL FROM or DATA line that
1153 triggers this feature will elicit an SMTP response which
1154 (unfortunately) varies according to the listener.
1158 return an error code of 571.
1160 According to RFC2821, the correct thing to return in this situation is
1161 550 "Requested action not taken: mailbox unavailable" (the draft adds
1162 "[E.g., mailbox not found, no access, or command rejected for policy
1165 Older versions of the
1167 MTA return 501 "Syntax error in parameters or arguments".
1171 MTA runs 554 as an antispam response.
1174 may reject code with a 500 response (followed by an enhanced status
1175 code that contains more information).
1179 treats as antispam responses and discards
1180 the message can be set with the `antispam' option. This is one of the
1182 three circumstance under which fetchmail ever discards mail (the others
1183 are the 552 and 553 errors described below, and the suppression of
1184 multidropped messages with a message-ID already seen).
1188 is fetching from an IMAP server, the antispam response will be detected and
1189 the message rejected immediately after the headers have been fetched,
1190 without reading the message body. Thus, you won't pay for downloading
1191 spam message bodies.
1193 By default, the list of antispam responses is empty.
1195 If the \fIspambounce\fR option is on, mail that is spam-blocked
1196 triggers an RFC1892 bounce message informing the originator that we do
1197 not accept mail from it.
1199 .SH SMTP/ESMTP ERROR HANDLING
1200 Besides the spam-blocking described above, fetchmail takes special
1201 actions on the following SMTP/ESMTP error responses
1203 452 (insufficient system storage)
1204 Leave the message in the server mailbox for later retrieval.
1206 552 (message exceeds fixed maximum message size)
1207 Delete the message from the server. Send bounce-mail to the
1210 553 (invalid sending domain)
1211 Delete the message from the server. Don't even try to send
1212 bounce-mail to the originator.
1214 Other errors trigger bounce mail back to the originator.
1216 .SH THE RUN CONTROL FILE
1217 The preferred way to set up fetchmail is to write a
1218 \&\fI.fetchmailrc\fR file in your home directory (you may do this
1219 directly, with a text editor, or indirectly via \fIfetchmailconf\fR).
1220 When there is a conflict between the command-line arguments and the
1221 arguments in this file, the command-line arguments take precedence.
1223 To protect the security of your passwords,
1224 your \fI~/.fetchmailrc\fR may not normally have more than 0600 (u=rw,g=,o=) permissions;
1226 will complain and exit otherwise (this check is suppressed when
1229 You may read the \fI.fetchmailrc\fR file as a list of commands to
1232 is called with no arguments.
1233 .SS Run Control Syntax
1235 Comments begin with a '#' and extend through the end of the line.
1236 Otherwise the file consists of a series of server entries or global
1237 option statements in a free-format, token-oriented syntax.
1239 There are four kinds of tokens: grammar keywords, numbers
1240 (i.e. decimal digit sequences), unquoted strings, and quoted strings.
1241 A quoted string is bounded by double quotes and may contain
1242 whitespace (and quoted digits are treated as a string). An unquoted
1243 string is any whitespace-delimited token that is neither numeric, string
1244 quoted nor contains the special characters `,', `;', `:', or `='.
1246 Any amount of whitespace separates tokens in server entries, but is
1247 otherwise ignored. You may use standard C-style escapes (\en, \et,
1248 \eb, octal, and hex) to embed non-printable characters or string
1249 delimiters in strings.
1251 Each server entry consists of one of the keywords `poll' or `skip',
1252 followed by a server name, followed by server options, followed by any
1253 number of user descriptions. Note: the most common cause of syntax
1254 errors is mixing up user and server options.
1256 For backward compatibility, the word `server' is a synonym for `poll'.
1258 You can use the noise keywords `and', `with',
1259 \&`has', `wants', and `options' anywhere in an entry to make
1260 it resemble English. They're ignored, but but can make entries much
1261 easier to read at a glance. The punctuation characters ':', ';' and
1262 \&',' are also ignored.
1265 The `poll' verb tells fetchmail to query this host when it is run with
1266 no arguments. The `skip' verb tells
1268 not to poll this host unless it is explicitly named on the command
1269 line. (The `skip' verb allows you to experiment with test entries
1270 safely, or easily disable entries for hosts that are temporarily down.)
1272 .SS Keyword/Option Summary
1273 Here are the legal options. Keyword suffixes enclosed in
1274 square brackets are optional. Those corresponding to command-line
1275 options are followed by `-' and the appropriate option letter.
1276 If option is only relevant to a single mode of operation, it is noted
1277 as `s' or `m' for singledrop- or multidrop-mode, respectively.
1279 Here are the legal global options:
1283 Keyword Opt Mode Function
1286 Set a background poll interval in seconds
1288 set postmaster \& \& T{
1289 Give the name of the last-resort mail recipient
1291 set no bouncemail \& \& T{
1292 Direct error mail to postmaster rather than sender
1294 set no spambounce \& \& T{
1297 set logfile \& \& T{
1298 Name of a file to dump error and status messages to
1301 Name of the file to store UID lists in
1304 Do error logging through syslog(3).
1306 set no syslog \& \& T{
1307 Turn off error logging through syslog(3).
1309 set properties \& \& T{
1310 String value is ignored by fetchmail (may be used by extension scripts)
1314 Here are the legal server options:
1318 Keyword Opt Mode Function
1321 Specify DNS name of mailserver, overriding poll name
1324 Specify protocol (case insensitive):
1325 POP2, POP3, IMAP, APOP, KPOP
1327 local[domains] \& m T{
1328 Specify domain(s) to be regarded as local
1331 Specify TCP/IP service port
1333 auth[enticate] \& \& T{
1334 Set authentication type (default `any')
1337 Server inactivity timeout in seconds (default 300)
1340 Specify envelope-address header name
1343 Disable looking for envelope address
1346 Qmail virtual domain prefix to remove from user name
1349 Specify alternate DNS names of mailserver
1352 specify IP interface(s) that must be up for server poll to take place
1355 Specify IP address to monitor for activity
1358 Specify command through which to make server connections.
1361 Specify command through which to make listener connections.
1364 Enable DNS lookup for multidrop (default)
1367 Disable DNS lookup for multidrop
1370 Do comparison by IP address for multidrop
1372 no checkalias \& m T{
1373 Do comparison by name for multidrop (default)
1376 Force POP3 to use client-side UIDLs
1379 Turn off POP3 use of client-side UIDLs (default)
1382 Only check this site every N poll cycles; N is a numeric argument.
1385 Add poll tracing information to the Received header
1388 Pass in IPsec security option request.
1391 Set Kerberos principal (only useful with imap and kerberos)
1394 Set name for RFC2554 authentication to the ESMTP server.
1396 esmtppassword \& \& T{
1397 Set password for RFC2554 authentication to the ESMTP server.
1401 Here are the legal user options:
1405 Keyword Opt Mode Function
1408 Set remote user name
1409 (local user name if name followed by `here')
1412 Connect local and remote user names
1415 Connect local and remote user names
1418 Specify remote account password
1421 Connect to server over the specified base protocol using SSL encryption
1424 Specify file for client side public SSL certificate
1427 Specify file for client side private SSL key
1430 Force ssl protocol for connection
1433 Specify remote folder to query
1436 Specify smtp host(s) to forward to
1438 fetchdomains \& m T{
1439 Specify domains for which mail should be fetched
1441 smtpaddress -D \& T{
1442 Specify the domain to be put in RCPT TO lines
1445 Specify the user and domain to be put in RCPT TO lines
1448 Specify what SMTP returns are interpreted as spam-policy blocks
1451 Specify MDA for local delivery
1454 Specify BSMTP batch file to append to
1457 Command to be executed before each connection
1459 postconnect \& \& T{
1460 Command to be executed after each connection
1463 Don't delete seen messages from server
1466 Flush all seen messages before querying
1469 Fetch all messages whether seen or not
1472 Rewrite destination addresses for reply (default)
1475 Strip carriage returns from ends of lines
1478 Force carriage returns at ends of lines
1481 Force BODY=8BITMIME to ESMTP listener
1484 Strip Status and X-Mozilla-Status lines out of incoming mail
1486 dropdelivered \& \& T{
1487 Strip Delivered-To lines out of incoming mail
1490 Convert quoted-printable to 8-bit in MIME messages
1493 Idle waiting for new messages after each poll (IMAP only)
1496 Delete seen messages from server (default)
1499 Don't flush all seen messages before querying (default)
1501 no fetchall \& \& T{
1502 Retrieve only new messages (default)
1505 Don't rewrite headers
1508 Don't strip carriage returns (default)
1511 Don't force carriage returns at EOL (default)
1513 no pass8bits \& \& T{
1514 Don't force BODY=8BITMIME to ESMTP listener (default)
1516 no dropstatus \& \& T{
1517 Don't drop Status headers (default)
1519 no dropdelivered \& \& T{
1520 Don't drop Delivered-To headers (default)
1522 no mimedecode \& \& T{
1523 Don't convert quoted-printable to 8-bit in MIME messages (default)
1526 Don't idle waiting for new messages after each poll (IMAP only)
1529 Set message size limit
1532 Set message size warning interval
1535 Max # messages to forward in single connect
1538 Max # messages to fetch in single connect
1540 fetchsizelimit \& \& T{
1541 Max # message sizes to fetch in single transaction
1544 Use binary search for first unseen message (POP3 only)
1547 Perform an expunge on every #th message (IMAP and POP3 only)
1550 String value is ignored by fetchmail (may be used by extension scripts)
1554 Remember that all user options must \fIfollow\fR all server options.
1556 In the .fetchmailrc file, the `envelope' string argument may be
1557 preceded by a whitespace-separated number. This number, if specified,
1558 is the number of such headers to skip (that is, an argument of 1
1559 selects the second header of the given type). This is sometime useful
1560 for ignoring bogus Received headers created by an ISP's local delivery
1562 .SS Keywords Not Corresponding To Option Switches
1564 The `folder' and `smtphost' options (unlike their command-line
1565 equivalents) can take a space- or comma-separated list of names
1568 All options correspond to the obvious command-line arguments, except
1569 the following: `via', `interval', `aka', `is', `to', `dns'/`no dns',
1570 `checkalias'/`no checkalias', `password', `preconnect', `postconnect',
1571 `localdomains', `stripcr'/`no stripcr', `forcecr'/`no forcecr',
1572 `pass8bits'/`no pass8bits' `dropstatus/no dropstatus',
1573 `dropdelivered/no dropdelivered', `mimedecode/no mimedecode', `idle/no
1574 idle', and `no envelope'.
1576 The `via' option is for if you want to have more
1577 than one configuration pointing at the same site. If it is present,
1578 the string argument will be taken as the actual DNS name of the
1579 mailserver host to query.
1580 This will override the argument of poll, which can then simply be a
1581 distinct label for the configuration (e.g. what you would give on the
1582 command line to explicitly query this host).
1584 The `interval' option (which takes a numeric argument) allows you to poll a
1585 server less frequently than the basic poll interval. If you say
1586 \&`interval N' the server this option is attached to will only be
1587 queried every N poll intervals.
1589 The `is' or `to' keywords associate the following local (client)
1590 name(s) (or server-name to client-name mappings separated by =) with
1591 the mailserver user name in the entry. If an is/to list has `*' as
1592 its last name, unrecognized names are simply passed through.
1594 A single local name can be used to support redirecting your mail when
1595 your username on the client machine is different from your name on the
1596 mailserver. When there is only a single local name, mail is forwarded
1597 to that local username regardless of the message's Received, To, Cc,
1598 and Bcc headers. In this case
1600 never does DNS lookups.
1602 When there is more than one local name (or name mapping) the
1603 \fIfetchmail\fR code does look at the Received, To, Cc, and Bcc
1604 headers of retrieved mail (this is `multidrop mode'). It looks for
1605 addresses with hostname parts that match your poll name or your `via',
1606 `aka' or `localdomains' options, and usually also for hostname parts
1607 which DNS tells it are aliases of the mailserver. See the discussion
1608 of `dns', `checkalias', `localdomains', and `aka' for details on how
1609 matching addresses are handled.
1611 If \fIfetchmail\fR cannot match any mailserver usernames or
1612 localdomain addresses, the mail will be bounced.
1613 Normally it will be bounced to the sender, but if `nobounce' is on
1614 it will go to the postmaster (which in turn defaults to being the
1617 The `dns' option (normally on) controls the way addresses from
1618 multidrop mailboxes are checked. On, it enables logic to check each
1619 host address that doesn't match an `aka' or `localdomains' declaration
1620 by looking it up with DNS. When a mailserver username is recognized
1621 attached to a matching hostname part, its local mapping is added to
1622 the list of local recipients.
1624 The `checkalias' option (normally off) extends the lookups performed
1625 by the `dns' keyword in multidrop mode, providing a way to cope with
1626 remote MTAs that identify themselves using their canonical name, while
1627 they're polled using an alias.
1628 When such a server is polled, checks to extract the envelope address
1631 reverts to delivery using the To/Cc/Bcc headers (See below
1632 `Header vs. Envelope addresses').
1633 Specifying this option instructs
1635 to retrieve all the IP addresses associated with both the poll name
1636 and the name used by the remote MTA and to do a comparison of the IP
1637 addresses. This comes in handy in situations where the remote server
1638 undergoes frequent canonical name changes, that would otherwise
1639 require modifications to the rcfile. `checkalias' has no effect if
1640 `no dns' is specified in the rcfile.
1642 The `aka' option is for use with multidrop mailboxes. It allows you
1643 to pre-declare a list of DNS aliases for a server. This is an
1644 optimization hack that allows you to trade space for speed. When
1646 while processing a multidrop mailbox, grovels through message headers
1647 looking for names of the mailserver, pre-declaring common ones can
1648 save it from having to do DNS lookups. Note: the names you give
1649 as arguments to `aka' are matched as suffixes -- if you specify
1650 (say) `aka netaxs.com', this will match not just a hostname
1651 netaxs.com, but any hostname that ends with `.netaxs.com'; such as
1652 (say) pop3.netaxs.com and mail.netaxs.com.
1654 The `localdomains' option allows you to declare a list of domains
1655 which fetchmail should consider local. When fetchmail is parsing
1656 address lines in multidrop modes, and a trailing segment of a host
1657 name matches a declared local domain, that address is passed through
1658 to the listener or MDA unaltered (local-name mappings are \fInot\fR
1661 If you are using `localdomains', you may also need to specify \&`no
1662 envelope', which disables \fIfetchmail\fR's normal attempt to deduce
1663 an envelope address from the Received line or X-Envelope-To header or
1664 whatever header has been previously set by `envelope'. If you set `no
1665 envelope' in the defaults entry it is possible to undo that in
1666 individual entries by using `envelope <string>'. As a special case,
1667 \&`envelope "Received"' restores the default parsing of
1670 The \fBpassword\fR option requires a string argument, which is the password
1671 to be used with the entry's server.
1673 The `preconnect' keyword allows you to specify a shell command to be
1674 executed just before each time
1676 establishes a mailserver connection. This may be useful if you are
1677 attempting to set up secure POP connections with the aid of
1679 If the command returns a nonzero status, the poll of that mailserver
1682 Similarly, the `postconnect' keyword similarly allows you to specify a
1683 shell command to be executed just after each time a mailserver
1684 connection is taken down.
1686 The `forcecr' option controls whether lines terminated by LF only are
1687 given CRLF termination before forwarding. Strictly speaking RFC821
1688 requires this, but few MTAs enforce the requirement it so this option
1689 is normally off (only one such MTA, qmail, is in significant use at
1692 The `stripcr' option controls whether carriage returns are stripped
1693 out of retrieved mail before it is forwarded. It is normally not
1694 necessary to set this, because it defaults to `on' (CR stripping
1695 enabled) when there is an MDA declared but `off' (CR stripping
1696 disabled) when forwarding is via SMTP. If `stripcr' and `forcecr' are
1697 both on, `stripcr' will override.
1699 The `pass8bits' option exists to cope with Microsoft mail programs that
1700 stupidly slap a "Content-Transfer-Encoding: 7bit" on everything. With
1701 this option off (the default) and such a header present,
1703 declares BODY=7BIT to an ESMTP-capable listener; this causes problems for
1704 messages actually using 8-bit ISO or KOI-8 character sets, which will
1705 be garbled by having the high bits of all characters stripped. If
1706 \&`pass8bits' is on,
1708 is forced to declare BODY=8BITMIME to any ESMTP-capable listener. If
1709 the listener is 8-bit-clean (as all the major ones now are) the right
1710 thing will probably result.
1712 The `dropstatus' option controls whether nonempty Status and
1713 X-Mozilla-Status lines are retained in fetched mail (the default) or
1714 discarded. Retaining them allows your MUA to see what messages (if
1715 any) were marked seen on the server. On the other hand, it can
1716 confuse some new-mail notifiers, which assume that anything with a
1717 Status line in it has been seen. (Note: the empty Status lines
1718 inserted by some buggy POP servers are unconditionally discarded.)
1720 The `dropdelivered' option controls whether Delivered-To headers will
1721 be kept in fetched mail (the default) or discarded. These headers are
1722 added by Qmail and Postfix mailservers in order to avoid mail loops but
1723 may get in your way if you try to "mirror" a mailserver within the same
1724 domain. Use with caution.
1726 The `mimedecode' option controls whether MIME messages using the
1727 quoted-printable encoding are automatically converted into pure 8-bit
1728 data. If you are delivering mail to an ESMTP-capable, 8-bit-clean
1729 listener (that includes all of the major MTAs like sendmail), then
1730 this will automatically convert quoted-printable message headers and
1731 data into 8-bit data, making it easier to understand when reading
1732 mail. If your e-mail programs know how to deal with MIME messages,
1733 then this option is not needed. The mimedecode option is off by
1734 default, because doing RFC2047 conversion on headers throws away
1735 character-set information and can lead to bad results if the encoding
1736 of the headers differs from the body encoding.
1738 The `idle' option is intended to be used with IMAP servers supporting
1739 the RFC2177 IDLE command extension, but does not strictly require it.
1740 If it is enabled, and fetchmail detects that IDLE is supported, an
1741 IDLE will be issued at the end of each poll. This will tell the IMAP
1742 server to hold the connection open and notify the client when new mail
1743 is available. If IDLE is not supported, fetchmail will simulate it by
1744 periodically issuing NOOP. If you need to poll a link frequently, IDLE
1745 can save bandwidth by eliminating TCP/IP connects and LOGIN/LOGOUT
1746 sequences. On the other hand, an IDLE connection will eat almost all
1747 of your fetchmail's time, because it will never drop the connection
1748 and allow other pools to occur unless the server times out the IDLE.
1749 It also doesn't work with multiple folders; only the first folder will
1753 The `properties' option is an extension mechanism. It takes a string
1754 argument, which is ignored by fetchmail itself. The string argument may be
1755 used to store configuration information for scripts which require it.
1756 In particular, the output of `--configdump' option will make properties
1757 associated with a user entry readily available to a Python script.
1759 .SS Miscellaneous Run Control Options
1760 The words `here' and `there' have useful English-like
1761 significance. Normally `user eric is esr' would mean that
1762 mail for the remote user `eric' is to be delivered to `esr',
1763 but you can make this clearer by saying `user eric there is esr here',
1764 or reverse it by saying `user esr here is eric there'
1766 Legal protocol identifiers for use with the `protocol' keyword are:
1779 Legal authentication types are `any', `password', `kerberos', 'kerberos_v5'
1780 and `gssapi', `cram-md5', `otp', `ntlm', `ssh`.
1781 The `password' type specifies authentication by normal transmission of a
1782 password (the password may be plain text or subject to
1783 protocol-specific encryption as in APOP); `kerberos' tells
1784 \fIfetchmail\fR to try to get a Kerberos ticket at the start of each
1785 query instead, and send an arbitrary string as the password; and
1786 `gssapi' tells fetchmail to use GSSAPI authentication. See the description
1787 of the `auth' keyword for more.
1789 Specifying `kpop' sets POP3 protocol over port 1109 with Kerberos V4
1790 authentication. These defaults may be overridden by later options.
1792 There are currently four global option statements; `set logfile'
1793 followed by a string sets the same global specified by --logfile. A
1794 command-line --logfile option will override this. Also, `set daemon'
1795 sets the poll interval as --daemon does. This can be overridden by a
1796 command-line --daemon option; in particular --daemon 0 can be used to
1797 force foreground operation. The `set postmaster' statement sets the
1798 address to which multidrop mail defaults if there are no local
1799 matches. Finally, `set syslog' sends log messages to syslogd(8).
1801 .SH INTERACTION WITH RFC 822
1802 When trying to determine the originating address of a message,
1803 fetchmail looks through headers in the following order:
1807 Resent-Sender: (ignored if it doesn't contain an @ or !)
1808 Sender: (ignored if it doesn't contain an @ or !)
1815 The originating address is used for logging, and to set the MAIL FROM
1816 address when forwarding to SMTP. This order is intended to cope
1817 gracefully with receiving mailing list messages in multidrop mode. The
1818 intent is that if a local address doesn't exist, the bounce message
1819 won't be returned blindly to the author or to the list itself, but
1820 rather to the list manager (which is less annoying).
1822 In multidrop mode, destination headers are processed as follows:
1823 First, fetchmail looks for the Received: header (or whichever one is
1824 specified by the `envelope' option) to determine the local
1825 recipient address. If the mail is addressed to more than one recipient,
1826 the Received line won't contain any information regarding recipient addresses.
1828 Then fetchmail looks for the Resent-To:, Resent-Cc:, and Resent-Bcc:
1829 lines. If they exist, they should contain the final recipients and
1830 have precedence over their To:/Cc:/Bcc: counterparts. If the Resent-*
1831 lines don't exist, the To:, Cc:, Bcc: and Apparently-To: lines are
1832 looked for. (The presence of a Resent-To: is taken to imply that the
1833 person referred by the To: address has already received the original
1836 .SH CONFIGURATION EXAMPLES
1837 Note that although there are password declarations in a good many
1838 of the examples below, this is mainly for illustrative purposes.
1839 We recommend stashing account/password pairs in your $HOME/.netrc
1840 file, where they can be used not just by fetchmail but by ftp(1) and
1846 poll SERVERNAME protocol PROTOCOL username NAME password PASSWORD
1852 poll pop.provider.net protocol pop3 username "jsmith" password "secret1"
1855 Or, using some abbreviations:
1858 poll pop.provider.net proto pop3 user "jsmith" password "secret1"
1861 Multiple servers may be listed:
1864 poll pop.provider.net proto pop3 user "jsmith" pass "secret1"
1865 poll other.provider.net proto pop2 user "John.Smith" pass "My^Hat"
1868 Here's a version of those two with more whitespace and some noise words:
1871 poll pop.provider.net proto pop3
1872 user "jsmith", with password secret1, is "jsmith" here;
1873 poll other.provider.net proto pop2:
1874 user "John.Smith", with password "My^Hat", is "John.Smith" here;
1877 This version is much easier to read and doesn't cost significantly
1878 more (parsing is done only once, at startup time).
1881 If you need to include whitespace in a parameter string, enclose the
1882 string in double quotes. Thus:
1885 poll mail.provider.net with proto pop3:
1886 user "jsmith" there has password "u can't krak this"
1887 is jws here and wants mda "/bin/mail"
1890 You may have an initial server description headed by the keyword
1891 `defaults' instead of `poll' followed by a name. Such a record
1892 is interpreted as defaults for all queries to use. It may be overwritten
1893 by individual server descriptions. So, you could write:
1898 poll pop.provider.net
1900 poll mail.provider.net
1901 user "jjsmith" there has password "secret2"
1904 It's possible to specify more than one user per server (this is only
1905 likely to be useful when running fetchmail in daemon mode as root).
1906 The `user' keyword leads off a user description, and every user specification
1907 in a multi-user entry must include it. Here's an example:
1910 poll pop.provider.net proto pop3 port 3111
1911 user "jsmith" with pass "secret1" is "smith" here
1912 user jones with pass "secret2" is "jjones" here keep
1915 This associates the local username `smith' with the pop.provider.net
1916 username `jsmith' and the local username `jjones' with the
1917 pop.provider.net username `jones'. Mail for `jones' is kept on the
1918 server after download.
1920 Here's what a simple retrieval configuration for a multi-drop mailbox
1924 poll pop.provider.net:
1925 user maildrop with pass secret1 to golux 'hurkle'='happy' snark here
1928 This says that the mailbox of account `maildrop' on the server is a
1929 multi-drop box, and that messages in it should be parsed for the
1930 server user names `golux', `hurkle', and `snark'. It further
1931 specifies that `golux' and `snark' have the same name on the
1932 client as on the server, but mail for server user `hurkle' should be
1933 delivered to client user `happy'.
1935 Here's an example of another kind of multidrop connection:
1938 poll pop.provider.net localdomains loonytoons.org toons.org:
1939 user maildrop with pass secret1 to * here
1942 This also says that the mailbox of account `maildrop' on the server is
1943 a multi-drop box. It tells fetchmail that any address in the
1944 loonytoons.org or toons.org domains (including sub-domain addresses like
1945 `joe@daffy.loonytoons.org') should be passed through to the local SMTP
1946 listener without modification. Be careful of mail loops if you do this!
1948 Here's an example configuration using ssh and the plugin option. The
1949 queries are made directly on the stdin and stdout of imapd via ssh.
1950 Note that in this setup, IMAP authentication can be skipped.
1953 poll mailhost.net with proto imap:
1954 plugin "ssh %h /usr/sbin/imapd" auth ssh;
1955 user esr is esr here
1958 .SH THE USE AND ABUSE OF MULTIDROP MAILBOXES
1959 Use the multiple-local-recipients feature with caution -- it can bite.
1960 All multidrop features are ineffective in ETRN and ODMR modes.
1962 Also, note that in multidrop mode duplicate mails are suppressed. A
1963 piece of mail is considered duplicate if it has the same message-ID as
1964 the message immediately preceding and more than one addressee. Such
1965 runs of messages may be generated when copies of a message addressed
1966 to multiple users are delivered to a multidrop box.
1968 .SS Header vs. Envelope addresses
1969 The fundamental problem is that by having your mailserver toss several
1970 peoples' mail in a single maildrop box, you may have thrown away
1971 potentially vital information about who each piece of mail was
1972 actually addressed to (the `envelope address', as opposed to the
1973 header addresses in the RFC822 To/Cc/Bcc headers). This `envelope
1974 address' is the address you need in order to reroute mail properly.
1978 can deduce the envelope address. If the mailserver MTA is
1980 and the item of mail had just one recipient, the MTA will have written
1981 a `by/for' clause that gives the envelope addressee into its Received
1982 header. But this doesn't work reliably for other MTAs, nor if there is
1983 more than one recipient. By default, \fIfetchmail\fR looks for
1984 envelope addresses in these lines; you can restore this default with
1985 -E "Received" or \&`envelope Received'.
1987 Alternatively, some SMTP listeners and/or mail servers insert a header
1988 in each message containing a copy of the envelope addresses. This
1989 header (when it exists) is often `X-Envelope-To'. Fetchmail's
1990 assumption about this can be changed with the -E or `envelope' option.
1991 Note that writing an envelope header of this kind exposes the names of
1992 recipients (including blind-copy recipients) to all receivers of the
1993 messages; it is therefore regarded by some administrators as a
1994 security/privacy problem.
1996 A slight variation of the `X-Envelope-To' header is the `Delivered-To' put
1997 by qmail to avoid mail loops. It will probably prefix the user name with a
1998 string that normally matches the user's domain. To remove this prefix you
1999 can use the -Q or `qvirtual' option.
2001 Sometimes, unfortunately, neither of these methods works. When they
2002 all fail, fetchmail must fall back on the contents of To/Cc/Bcc
2003 headers to try to determine recipient addressees -- and these are not
2004 reliable. In particular, mailing-list software often ships mail with
2005 only the list broadcast address in the To header.
2009 cannot deduce a recipient address that is local, and the intended
2010 recipient address was anyone other than fetchmail's invoking user,
2011 mail will get lost. This is what makes the multidrop feature risky.
2013 A related problem is that when you blind-copy a mail message, the Bcc
2014 information is carried \fIonly\fR as envelope address (it's not put
2015 in the headers fetchmail can see unless there is an X-Envelope
2016 header). Thus, blind-copying to someone who gets mail over a
2017 fetchmail link will fail unless the the mailserver host routinely
2018 writes X-Envelope or an equivalent header into messages in your maildrop.
2020 .SS Good Ways To Use Multidrop Mailboxes
2021 Multiple local names can be used to administer a mailing list from the
2022 client side of a \fIfetchmail\fR collection. Suppose your name is
2023 \&`esr', and you want to both pick up your own mail and maintain a mailing
2024 list called (say) "fetchmail-friends", and you want to keep the alias
2025 list on your client machine.
2027 On your server, you can alias \&`fetchmail-friends' to `esr'; then, in
2028 your \fI.fetchmailrc\fR, declare \&`to esr fetchmail-friends here'.
2029 Then, when mail including `fetchmail-friends' as a local address
2030 gets fetched, the list name will be appended to the list of
2031 recipients your SMTP listener sees. Therefore it will undergo alias
2032 expansion locally. Be sure to include `esr' in the local alias
2033 expansion of fetchmail-friends, or you'll never see mail sent only to
2034 the list. Also be sure that your listener has the "me-too" option set
2035 (sendmail's -oXm command-line option or OXm declaration) so your name
2036 isn't removed from alias expansions in messages you send.
2038 This trick is not without its problems, however. You'll begin to see
2039 this when a message comes in that is addressed only to a mailing list
2040 you do \fInot\fR have declared as a local name. Each such message
2041 will feature an `X-Fetchmail-Warning' header which is generated
2042 because fetchmail cannot find a valid local name in the recipient
2043 addresses. Such messages default (as was described above) to being
2044 sent to the local user running
2046 but the program has no way to know that that's actually the right thing.
2048 .SS Bad Ways To Abuse Multidrop Mailboxes
2049 Multidrop mailboxes and
2051 serving multiple users in daemon mode do not mix. The problem, again, is
2052 mail from mailing lists, which typically does not have an individual
2053 recipient address on it. Unless
2055 can deduce an envelope address, such mail will only go to the account
2056 running fetchmail (probably root). Also, blind-copied users are very
2057 likely never to see their mail at all.
2059 If you're tempted to use
2061 to retrieve mail for multiple users from a single mail drop via POP or
2062 IMAP, think again (and reread the section on header and envelope
2063 addresses above). It would be smarter to just let the mail sit in the
2064 mailserver's queue and use fetchmail's ETRN or ODMR modes to trigger
2065 SMTP sends periodically (of course, this means you have to poll more
2066 frequently than the mailserver's expiry period). If you can't arrange
2067 this, try setting up a UUCP feed.
2069 If you absolutely \fImust\fR use multidrop for this purpose, make sure
2070 your mailserver writes an envelope-address header that fetchmail can
2071 see. Otherwise you \fIwill\fR lose mail and it \fIwill\fR come back
2074 .SS Speeding Up Multidrop Checking
2075 Normally, when multiple users are declared
2077 extracts recipient addresses as described above and checks each host
2078 part with DNS to see if it's an alias of the mailserver. If so, the
2079 name mappings described in the to ... here declaration are done and
2080 the mail locally delivered.
2082 This is the safest but also slowest method. To speed it up,
2083 pre-declare mailserver aliases with `aka'; these are checked before
2084 DNS lookups are done. If you're certain your aka list contains
2086 DNS aliases of the mailserver (and all MX names pointing at it)
2087 you can declare `no dns' to suppress DNS lookups entirely and
2088 \fIonly\fR match against the aka list.
2091 To facilitate the use of
2093 in shell scripts, an exit code is returned to give an indication
2094 of what occurred during a given connection.
2096 The exit codes returned by
2100 One or more messages were successfully retrieved (or, if the -c option
2101 was selected, were found waiting but not retrieved).
2103 There was no mail awaiting retrieval. (There may have been old mail still
2104 on the server but not selected for retrieval.)
2106 An error was encountered when attempting to open a socket to retrieve
2107 mail. If you don't know what a socket is, don't worry about it --
2108 just treat this as an 'unrecoverable error'. This error can also be
2109 because a protocol fetchmail wants to use is not listed in /etc/services.
2111 The user authentication step failed. This usually means that a bad
2112 user-id, password, or APOP id was specified. Or it may mean that you
2113 tried to run fetchmail under circumstances where it did not have
2114 standard input attached to a terminal and could not prompt for a
2117 Some sort of fatal protocol error was detected.
2119 There was a syntax error in the arguments to
2122 The run control file had bad permissions.
2124 There was an error condition reported by the server. Can also
2127 timed out while waiting for the server.
2129 Client-side exclusion error. This means
2131 either found another copy of itself already running, or failed in such
2132 a way that it isn't sure whether another copy is running.
2134 The user authentication step failed because the server responded "lock
2135 busy". Try again after a brief pause! This error is not implemented
2136 for all protocols, nor for all servers. If not implemented for your
2137 server, "3" will be returned instead, see above. May be returned when
2138 talking to qpopper or other servers that can respond with "lock busy"
2139 or some similar text containing the word "lock".
2143 run failed while trying to do an SMTP port open or transaction.
2145 Fatal DNS error. Fetchmail encountered an error while performing
2146 a DNS lookup at startup and could not proceed.
2148 BSMTP batch file could not be opened.
2150 Poll terminated by a fetch limit (see the --fetchlimit option).
2152 Server busy indication.
2154 Server timed out during an IMAP IDLE.
2156 Internal error. You should see a message on standard error with
2161 queries more than one host, return status is 0 if \fIany\fR query
2162 successfully retrieved mail. Otherwise the returned error status is
2163 that of the last host queried.
2168 default run control file
2171 default location of file associating hosts with last message IDs seen
2172 (used only with newer RFC1939-compliant POP3 servers supporting the
2176 lock file to help prevent concurrent runs (non-root mode).
2179 your FTP run control file, which (if present) will be searched for
2180 passwords as a last resort before prompting for one interactively.
2182 /var/run/fetchmail.pid
2183 lock file to help prevent concurrent runs (root mode, Linux systems).
2186 lock file to help prevent concurrent runs (root mode, systems without /var/run).
2189 If the FETCHMAILUSER variable is set, it is used as the name of the
2190 calling user (default local name) for purposes such as mailing error
2191 notifications. Otherwise, if either the LOGNAME or USER variable is
2192 correctly set (e.g. the corresponding UID matches the session user ID)
2193 then that name is used as the default local name. Otherwise
2194 \fBgetpwuid\fR(3) must be able to retrieve a password entry for the
2195 session ID (this elaborate logic is designed to handle the case of
2196 multiple names per userid gracefully).
2198 If the environment variable FETCHMAILHOME is set to a valid and
2199 existing directory name, the .fetchmailrc and .fetchids and
2200 \&.fetchmail.pid files are put there instead of in the invoking user's
2201 home directory (and lose the leading dots on their names). The
2202 \&.netrc file is looked for in the the invoking user's home directory
2203 regardless of FETCHMAILHOME's setting.
2205 If the HOME_ETC variable is set, file $HOME_ETC/.fetchmailrc is used
2206 instead of ~/.fetchmailrc.
2211 daemon is running as root, SIGHUP wakes it up from its sleep phase and
2212 forces a poll of all non-skipped servers (this is in accordance with
2213 the usual conventions for system daemons).
2217 is running in daemon mode as non-root, use SIGUSR1 to wake it (this is
2218 so SIGHUP due to logout can retain the default action of killing it).
2222 in foreground while a background fetchmail is running will do
2223 whichever of these is appropriate to wake it up.
2225 .SH BUGS AND KNOWN PROBLEMS
2226 The mda and plugin options interact badly. In order to collect error
2227 status from the MDA, fetchmail has to change its normal signal
2228 handling so that dead plugin processes don't get reaped until the end
2229 of the poll cycle. This can cause resource starvation if too many
2230 zombies accumulate. So either don't deliver to a MDA using plugins or
2231 risk being overrun by an army of undead.
2233 The RFC822 address parser used in multidrop mode chokes on some
2234 @-addresses that are technically legal but bizarre. Strange uses of
2235 quoting and embedded comments are likely to confuse it.
2237 In a message with multiple envelope headers, only the last one
2238 processed will be visible to fetchmail. To get around this, use a
2239 mailserver-side filter that consolidates the contents of all envelope
2240 headers into a single one (procmail, mailagent, or maildrop can be
2241 programmed to do this fairly easily).
2243 Use of some of these protocols requires that the program send
2244 unencrypted passwords over the TCP/IP connection to the mailserver.
2245 This creates a risk that name/password pairs might be snaffled with a
2246 packet sniffer or more sophisticated monitoring software. Under Linux
2247 and FreeBSD, the --interface option can be used to restrict polling to
2248 availability of a specific interface device with a specific local or
2249 remote IP address, but snooping is still possible if (a) either host
2250 has a network device that can be opened in promiscuous mode, or (b)
2251 the intervening network link can be tapped. We recommend the use of
2253 tunnelling to not only shroud your passwords but encrypt the entire
2256 Use of the %F or %T escapes in an mda option could open a security
2257 hole, because they pass text manipulable by an attacker to a shell
2258 command. Potential shell characters are replaced by `_' before
2259 execution. The hole is further reduced by the fact that fetchmail
2260 temporarily discards any suid privileges it may have while running the
2261 MDA. For maximum safety, however, don't use an mda command containing
2262 %F or %T when fetchmail is run from the root account itself.
2264 Fetchmail's method of sending bouncemail and spam bounces requires that
2265 port 25 of localhost be available for sending mail via SMTP.
2269 while a background instance is running and break the syntax, the
2270 background instance will die silently. Unfortunately, it can't
2271 die noisily because we don't yet know whether syslog should be enabled.
2272 On some systems, fetchmail dies quietly even if there is no syntax
2273 error; this seems to have something to do with buggy terminal ioctl
2276 The -f - option (reading a configuration from stdin) is incompatible
2277 with the plugin option.
2279 The `principal' option only handles Kerberos IV, not V.
2281 Send comments, bug reports, gripes, and the like to the
2282 fetchmail-devel list <fetchmail-devel@lists.berlios.de>. An HTML FAQ is
2283 available at the fetchmail home page; surf to
2284 http://fetchmail.berlios.de/ or do a WWW search for pages with
2285 `fetchmail' in their titles.
2288 Eric S. Raymond <esr@snark.thyrsus.com>. Too many other people to
2289 name here have contributed code and patches.
2290 This program is descended from and replaces
2292 by Carl Harris <ceharris@mal.com>; the internals have become quite different,
2293 but some of its interface design is directly traceable to that
2296 This manual page has been improved by R.\ Hannes Beinert.
2298 Fetchmail is currently maintained by Matthias Andree and Rob Funk.
2301 mutt(1), elm(1), mail(1), sendmail(8), popd(8), imapd(8), netrc(5)
2302 .SH APPLICABLE STANDARDS
2305 RFC 821, RFC2821, RFC 1869, RFC 1652, RFC 1870, RFC 1983, RFC 1985,
2309 RFC 822, RFC2822, RFC 1123, RFC 1892, RFC 1894.
2315 RFC 1081, RFC 1225, RFC 1460, RFC 1725, RFC1734, RFC 1939, RFC 1957,
2319 RFC 1460, RFC 1725, RFC 1939.
2328 RFC 1730, RFC 1731, RFC 1732, RFC 2060, RFC 2061, RFC 2195, RFC 2177,
projects / ~andy / fetchmail / blob