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 IMAPrev1.
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.
39 As each message is retrieved \fIfetchmail\fR normally delivers it via SMTP to
40 port 25 on the machine it is running on (localhost), just as though it
41 were being passed in over a normal TCP/IP link. The mail will then be
42 delivered locally via your system's MDA (Mail Delivery Agent, usually
43 \fIsendmail\fR(8) but your system may use a different one such
44 as \fIsmail\fR, \fImmdf\fR, \fIexim\fR, or \fIqmail\fR). All the
45 delivery-control mechanisms (such as \fI.forward\fR files) normally
46 available through your system MDA and local delivery agents will
49 If no port 25 listener is available, but your fetchmail compilation
50 detected or was told about a reliable local MDA, it will use that MDA
51 for local delivery instead. At build time, fetchmail normally looks
60 is available, it will assist you in setting up and editing a
61 fetchmailrc configuration. It runs under X and requires that the
62 language Python and the Tk toolkit be present on your system. If
63 you are first setting up fetchmail for single-user mode, it is
64 recommended that you use Novice mode. Expert mode provides
65 complete control of fetchmail configuration, including the
66 multidrop features. In either case, the `Autoprobe' button
67 will tell you the most capable protocol a given mailserver
68 supports, and warn you of potential problems with that server.
73 is controlled by command-line options and a run control file,
74 .IR ~/.fetchmailrc\fR ,
75 the syntax of which we describe in a later section (this file is what
76 the \fIfetchmailconf\fR program edits). Command-line options override
80 Each server name that you specify following the options on the
81 command line will be queried. If you don't specify any servers
82 on the command line, each `poll' entry in your
86 To facilitate the use of
88 in scripts and pipelines, it returns an appropriate exit code upon
89 termination -- see EXIT CODES below.
91 The following options modify the behavior of \fIfetchmail\fR. It is
92 seldom necessary to specify any of these once you have a
93 working \fI.fetchmailrc\fR file set up.
95 Almost all options have a corresponding keyword which can be used to
100 Some special options are not covered here, but are documented instead
101 in sections on AUTHENTICATION and DAEMON MODE which follow.
105 Displays the version information for your copy of
107 No mail fetch is performed.
108 Instead, for each server specified, all the option information
109 that would be computed if
111 were connecting to that server is displayed. Any non-printables in
112 passwords or other string names are shown as backslashed C-like
113 escape sequences. This option is useful for verifying that your
114 options are set the way you want them.
117 Return a status code to indicate whether there is mail waiting,
118 without actually fetching or deleting mail (see EXIT CODES below).
119 This option turns off daemon mode (in which it would be useless). It
120 doesn't play well with queries to multiple sites, and doesn't work
121 with ETRN or ODMR. It will return a false positive if you leave read but
122 undeleted mail in your server mailbox and your fetch protocol can't
123 tell kept messages from new ones. This means it will work with IMAP,
124 not work with POP2, and may occasionally flake out under POP3.
127 Silent mode. Suppresses all progress/status messages that are
128 normally echoed to standard error during a fetch (but does not
129 suppress actual error messages). The --verbose option overrides this.
132 Verbose mode. All control messages passed between
134 and the mailserver are echoed to stdout. Overrides --silent.
135 Doubling this option (-v -v) causes extra diagnostic information
141 Retrieve both old (seen) and new messages from the mailserver. The
142 default is to fetch only messages the server has not marked seen.
143 Under POP3, this option also forces the use of RETR rather than TOP.
144 Note that POP2 retrieval behaves as though --all is always on (see
145 RETRIEVAL FAILURE MODES below) and this option does not work with ETRN
150 Keep retrieved messages on the remote mailserver. Normally, messages
151 are deleted from the folder on the mailserver after they have been retrieved.
154 option causes retrieved messages to remain in your folder on the
155 mailserver. This option does not work with ETRN or ODMR.
159 Delete retrieved messages from the remote mailserver. This
160 option forces retrieved mail to be deleted. It may be useful if
161 you have specified a default of \fBkeep\fR in your
162 \&\fI.fetchmailrc\fR. This option is forced on with ETRN and ODMR.
165 POP3/IMAP only. Delete old (previously retrieved) messages from the mailserver
166 before retrieving new messages. This option does not work with ETRN or
168 Warning: if your local MTA hangs and fetchmail is aborted, the next
169 time you run fetchmail, it will delete mail that was never delivered to you.
170 What you probably want is the default setting: if you don't specify `-k', then
171 fetchmail will automatically delete messages after successful delivery.
172 .SS Protocol and Query Options
174 .B \-p, \--protocol <proto>
175 (Keyword: proto[col])
176 Specify the protocol to use when communicating with the remote
177 mailserver. If no protocol is specified, the default is AUTO.
179 may be one of the following:
182 Tries IMAP, POP3, and POP2 (skipping any of these for which support
183 has not been compiled in).
185 Post Office Protocol 2
187 Post Office Protocol 3
189 Use POP3 with old-fashioned MD5-challenge authentication.
191 Use POP3 with RPOP authentication.
193 Use POP3 with Kerberos V4 authentication on port 1109.
195 Use POP3 with Demon Internet's SDPS extensions.
197 IMAP2bis, IMAP4, or IMAP4rev1 (\fIfetchmail\fR autodetects their capabilities).
199 Use the ESMTP ETRN option.
201 Use the the On-Demand Mail Relay ESMTP profile.
204 All these alternatives work in basically the same way (communicating
205 with standard server daemons to fetch mail already delivered to a
206 mailbox on the server) except ETRN and ODMR. The ETRN mode
207 allows you to ask a compliant ESMTP server (such as BSD sendmail at
208 release 8.8.0 or higher) to immediately open a sender-SMTP connection
209 to your client machine and begin forwarding any items addressed to
210 your client machine in the server's queue of undelivered mail. The
211 ODMR mode requires an ODMR-capable server and works similarly to
212 ETRN, except that it does not require the client machine to have
217 Force UIDL use (effective only with POP3). Force client-side tracking
218 of `newness' of messages (UIDL stands for ``unique ID listing'' and is
219 described in RFC1725). Use with `keep' to use a mailbox as a baby
220 news drop for a group of users.
222 .B \-P, --port <portnumber>
224 The port option permits you to specify a TCP/IP port to connect on.
225 This option will seldom be necessary as all the supported protocols have
226 well-established default port numbers.
228 .B \--principal <principal>
230 The principal option permits you to specify a service principal for
231 mutual authentication. This is applicable to POP3 or IMAP with Kerberos
234 .B \-t, --timeout <seconds>
236 The timeout option allows you to set a server-nonresponse
237 timeout in seconds. If a mailserver does not send a greeting message
238 or respond to commands for the given number of seconds,
239 \fIfetchmail\fR will hang up on it. Without such a timeout
240 \fIfetchmail\fR might hang up indefinitely trying to fetch mail from a
241 down host. This would be particularly annoying for a \fIfetchmail\fR
242 running in background. There is a default timeout which fetchmail -V
243 will report. If a given connection receives too many timeouts in
244 succession, fetchmail will consider it wedged and stop retrying,
245 the calkling user will be notified by email if this happens.
247 .B \--plugin <command>
248 (Keyword: plugin) The plugin option allows you to use an external
249 program to establish the TCP connection. This is useful if you want
250 to use socks, SSL, ssh, or need some special firewalling setup. The
251 program will be looked up in $PATH and can optionally be passed the
252 hostname and port as arguments using "%h" and "%p" respectively (note
253 that the interpolation logic is rather primitive, and these token must
254 be bounded by whitespace or beginning of string or end of string).
255 Fetchmail will write to the plugin's stdin and read from the plugin's
258 .B \--plugout <command>
260 Identical to the plugin option above, but this one is used for the SMTP
261 connections (which will probably not need it, so it has been separated
264 .B \-r <name>, --folder <name>
266 Causes a specified non-default mail folder on the mailserver (or
267 comma-separated list of folders) to be retrieved. The syntax of the
268 folder name is server-dependent. This option is not available under
272 (Keyword: tracepolls)
273 Tell fetchail to poll trace information in the form `polling %s
274 account %s' to the Received line it generates, where the %s parts are
275 replaced by the user's remote name and the poll label (the Received
276 header also normally includes the server's truename). This can be
277 used to facilate mail filtering based on the account it is being
282 Causes the connection to the mail server to be encrypted via SSL. Connect
283 to the server using the specified base protocol over a connection secured
284 by SSL. SSL support must be present at the server. If no port is
285 specified, the connection is attempted to the well known port of the SSL
286 version of the base protocol. This is generally a different port than the
287 port used by the base protocol. For IMAP, this is port 143 for the clear
288 protocol and port 993 for the SSL secured protocol.
292 Specifies the file name of the client side public SSL certificate. Some
293 SSL encrypted servers may require client side keys and certificates for
294 authentication. In most cases, this is optional. This specifies
295 the location of the public key certificate to be presented to the server
296 at the time the SSL session is established. It is not required (but may
297 be provided) if the server does not require it. Some servers may
298 require it, some servers may request it but not require it, and some
299 servers may not request it at all. It may be the same file
300 as the private key (combined key and certificate file) but this is not
305 Specifies the file name of the client side private SSL key. Some SSL
306 encrypted servers may require client side keys and certificates for
307 authentication. In most cases, this is optional. This specifies
308 the location of the private key used to sign transactions with the server
309 at the time the SSL session is established. It is not required (but may
310 be provided) if the server does not require it. Some servers may
311 require it, some servers may request it but not require it, and some
312 servers may not request it at all. It may be the same file
313 as the public key (combined key and certificate file) but this is not
314 recommended. If a password is required to unlock the key, it will be
315 prompted for at the time just prior to establishing the session to the
316 server. This can cause some complications in daemon mode.
318 .B \--sslproto <name>
320 Forces an ssl protocol. Possible values are \&`\fBssl2\fR', `\fBssl3\fR' and
321 `\fBtls1\fR'. Try this if the default handshake does not work for your server.
325 Causes fetchmail to strictly check the server certificate against a set of
326 local trusted certificates (see the \fBsslcertpath\fR option). If the server
327 certificate is not signed by one of the trusted ones (directly or indirectly),
328 the SSL connection will fail. This checking should prevent man-in-the-middle
329 attacks against the SSL connection. Note that CRLs are seemingly not currently
330 supported by OpenSSL in certificate verification! Your system clock should
331 be reasonably accurate when using this option!
333 .B \--sslcertpath <directory>
334 (Keyword: sslcertpath)
335 Sets the directory fetchmail uses to look up local certificates. The default
336 is your OpenSSL default one. The directory must be hashed as OpenSSL expects
337 it - every time you add or modify a certificate in the directory, you need
338 to use the \fBc_rehash\fR tool (which comes with OpenSSL in the tools/
342 (Keyword: sslfingerprint)
343 Specify the fingerprint of the server key (an MD5 hash of the key) in
344 hexadecimal notation with colons separating groups of two digits. The letter
345 hex digits must be in upper case. This is the default format OpenSSL uses,
346 and the one fetchmail uses to report the fingerprint when an SSL connection
347 is established. When this is specified, fetchmail will compare the server key
348 fingerprint with the given one, and the connection will fail if they do not
349 match. This can be used to prevent man-in-the-middle attacks.
350 .SS Delivery Control Options
352 .B \-S <hosts>, --smtphost <hosts>
353 (Keyword: smtp[host])
354 Specify a hunt list of hosts to forward mail to (one or more
355 hostnames, comma-separated). Hosts are tried in list order; the first
356 one that is up becomes the forwarding target for the current run.
357 Normally, `localhost' is added to the end of the list as an invisible
358 default. However, when using Kerberos authentication, the FQDN of the
359 machine running fetchmail is added to the end of the list as an
360 invisible default. Each hostname may have a port number following the
361 host name. The port number is separated from the host name by a
362 slash; the default port is 25 (or ``smtp'' under IPv6). If you
363 specify an absolute pathname (beginning with a /), it will be
364 interpreted as the name of a UNIX socket accepting LMTP connections
365 (such as is supported by the Cyrus IMAP daemon) Example:
367 --smtphost server1,server2/2525,server3,/var/imap/socket/lmtp
369 This option can be used with ODMR, and will make fetchmail a relay
370 between the ODMR server and SMTP or LMTP receiver.
372 .B --fetchdomains <hosts>
373 (Keyword: fetchdomains)
374 In ETRN or ODMR mode, this option specifies the list of domains the
375 server should ship mail for once the connection is turned around. The
376 default is the FQDN of the machine running fetchmail.
378 .B \-D <domain>, --smtpaddress <domain>
379 (Keyword: smtpaddress) Specify the domain to be appended to addresses
380 in RCPT TO lines shipped to SMTP. The name of the SMTP server (as
381 specified by --smtphost, or defaulted to "localhost") is used when
382 this is not specified.
384 .B --smtpname <user@domain>
386 Specify the domain and user to be put in RCPT TO lines shipped to SMTP.
387 The default user is the current local user.
389 .B \-Z <nnn>, --antispam <nnn[, nnn]...>
391 Specifies the list of numeric SMTP errors that are to be interpreted
392 as a spam-block response from the listener. A value of -1 disables
393 this option. For the command-line option, the list values should
396 .B \-m <command>, \--mda <command>
398 You can force mail to be passed to an MDA directly (rather than
399 forwarded to port 25) with the -mda or -m option. To avoid losing
400 mail, use this option only with MDAs like procmail or sendmail that
401 return a nonzero status on disk-full and other resource-exhaustion
402 errors; the nonzero status tells fetchmail that delivery failed and
403 prevents the message from being deleted off the server. If
404 \fIfetchmail\fR is running as root, it sets its userid to that of the
405 target user while delivering mail through an MDA. Some possible MDAs
406 are "/usr/sbin/sendmail -oem -f %F %T", "/usr/bin/deliver" and
407 "/usr/bin/procmail -d %T" (but the latter is usually redundant as it's
408 what SMTP listeners normally forward to). Local delivery addresses
409 will be inserted into the MDA command wherever you place a %T; the
410 mail message's From address will be inserted where you place an %F.
411 Do \fInot\fR use an MDA invocation like "sendmail -oem -t" that
412 dispatches on the contents of To/Cc/Bcc, it will create mail loops and
413 bring the just wrath of many postmasters down upon your head.
417 Cause delivery via LMTP (Local Mail Transfer Protocol). A service
418 port \fImust\fR be explicitly specified (with a slash suffix) on each
419 host in the smtphost hunt list if this option is selected; the
420 default port 25 will (in accordance with RFC 2033) not be accepted.
422 .B \--bsmtp <filename>
424 Append fetched mail to a BSMTP file. This simply contains the SMTP
425 commands that would normally be generated by fetchmail when passing
426 mail to an SMTP listener daemon. An argument of `-' causes the mail
427 to be written to standard output. Note that fetchmail's
428 reconstruction of MAIL FROM and RCPT TO lines is not guaranteed
429 correct; the caveats discussed under THE USE AND ABUSE OF MULTIDROP
430 MAILBOXES below apply.
431 .SS Resource Limit Control Options
433 .B \-l <maxbytes>, --limit <maxbytes>
435 Takes a maximum octet size argument. Messages larger than this size
436 will not be fetched and will be left on the server (in foreground
437 sessions, the progress messages will note that they are "oversized").
438 If the fetch protocol permits (in particular, under IMAP or POP3
439 without the fetchall option) the message will not be marked seen An
440 explicit --limit of 0 overrides any limits set in your run control
441 file. This option is intended for those needing to strictly control
442 fetch time due to expensive and variable phone rates. In daemon mode,
443 oversize notifications are mailed to the calling user (see the
444 --warnings option). This option does not work with ETRN or ODMR.
446 .B \-w <interval>, --warnings <interval>
448 Takes an interval in seconds. When you call
450 with a `limit' option in daemon mode, this controls the interval at
451 which warnings about oversized messages are mailed to the calling user
452 (or the user specified by the `postmaster' option). One such
453 notification is always mailed at the end of the the first poll that
454 the oversized message is detected. Thereafter, renotification is
455 suppressed until after the warning interval elapses (it will take
456 place at the end of the first following poll).
458 .B -b <count>, --batchlimit <count>
459 (Keyword: batchlimit)
460 Specify the maximum number of messages that will be shipped to an SMTP
461 listener before the connection is deliberately torn down and rebuilt
462 (defaults to 0, meaning no limit). An explicit --batchlimit of 0
463 overrides any limits set in your run control file. While
464 \fBsendmail\fR(8) normally initiates delivery of a message immediately
465 after receiving the message terminator, some SMTP listeners are not so
466 prompt. MTAs like \fIqmail\fR(8) and \fIsmail\fR(8) may wait till the
467 delivery socket is shut down to deliver. This may produce annoying
468 delays when \fIfetchmail\fR is processing very large batches. Setting
469 the batch limit to some nonzero size will prevent these delays. This
470 option does not work with ETRN or ODMR.
472 .B -B <number>, --fetchlimit <number>
473 (Keyword: fetchlimit)
474 Limit the number of messages accepted from a given server in a single
475 poll. By default there is no limit. An explicit --fetchlimit of 0
476 overrides any limits set in your run control file.
477 This option does not work with ETRN or ODMR.
479 .B -e <count>, --expunge <count>
481 Arrange for deletions to be made final after a given number of
482 messages. Under POP2 or POP3, fetchmail cannot make deletions final
483 without sending QUIT and ending the session -- with this option on,
484 fetchmail will break a long mail retrieval session into multiple
485 subsessions, sending QUIT after each sub-session. This is a good
486 defense against line drops on POP3 servers that do not do the
487 equivalent of a QUIT on hangup. Under IMAP,
489 normally issues an EXPUNGE command after each deletion in order to
490 force the deletion to be done immediately. This is safest when your
491 connection to the server is flaky and expensive, as it avoids
492 resending duplicate mail after a line hit. However, on large
493 mailboxes the overhead of re-indexing after every message can slam the
494 server pretty hard, so if your connection is reliable it is good to do
495 expunges less frequently. If you specify this option to an integer N,
498 to only issue expunges on every Nth delete. An argument of zero
499 suppresses expunges entirely (so no expunges at all will be done until
500 the end of run). This option does not work with ETRN or ODMR.
501 .SS Authentication Options
503 .B \-u <name>, --username <name>
504 (Keyword: user[name])
505 Specifies the user identification to be used when logging in to the mailserver.
506 The appropriate user identification is both server and user-dependent.
507 The default is your login name on the client machine that is running
509 See USER AUTHENTICATION below for a complete description.
511 .B \-I <specification>, --interface <specification>
513 Require that a specific interface device be up and have a specific local
514 or remote IP address (or range) before polling. Frequently
516 is used over a transient point-to-point TCP/IP link established directly
517 to a mailserver via SLIP or PPP. That is a relatively secure channel.
518 But when other TCP/IP routes to the mailserver exist (e.g. when the link
519 is connected to an alternate ISP), your username and password may be
520 vulnerable to snooping (especially when daemon mode automatically polls
521 for mail, shipping a clear password over the net at predictable
522 intervals). The --interface option may be used to prevent this. When
523 the specified link is not up or is not connected to a matching IP
524 address, polling will be skipped. The format is:
526 interface/iii.iii.iii.iii/mmm.mmm.mmm.mmm
528 The field before the first slash is the interface name (i.e. sl0, ppp0
529 etc.). The field before the second slash is the acceptable IP address.
530 The field after the second slash is a mask which specifies a range of
531 IP addresses to accept. If no mask is present 255.255.255.255 is
532 assumed (i.e. an exact match). This option is currently only supported
533 under Linux and FreeBSD. Please see the
535 section for below for FreeBSD specific information.
537 .B \-M <interface>, --monitor <interface>
539 Daemon mode can cause transient links which are automatically taken down
540 after a period of inactivity (e.g. PPP links) to remain up
541 indefinitely. This option identifies a system TCP/IP interface to be
542 monitored for activity. After each poll interval, if the link is up but
543 no other activity has occurred on the link, then the poll will be
544 skipped. However, when fetchmail is woken up by a signal, the
545 monitor check is skipped and the poll goes through unconditionally.
546 This option is currently only supported under Linux and FreeBSD.
551 options to work for non root users under FreeBSD, the fetchmail binary
552 must be installed SGID kmem. This would be a security hole, but
553 fetchmail runs with the effective GID set to that of the kmem group
555 when interface data is being collected.
558 (Keyword: auth[enticate])
559 This option permits you to specify an authentication type (see USER
560 AUTHENTICATION below for details). The possible values are \fBany\fR,
561 \&`\fBpassword\fR', `\fBkerberos_v5\fR' and `\fBkerberos\fR' (or, for
562 excruciating exactness, `\fBkerberos_v4\fR'), \fRgssapi\fR,
563 \fIcram-md5\fR, \fIotp\fR, \fIntlm\fR, and \fBssh\fR. When \fBany\fR (the
564 default) is specified, fetchmail tries first methods that don't
565 require a password (GSSAPI, KERBEROS_IV); then it looks for methods
566 that mask your password (CRAM-MD5, X-OTP, NTLM); and only if the server
567 doesn't support any of those will it ship your password en clair.
568 Other values may be used to force various authentication methods
569 (\fBssh\fR suppresses authentication). Any value other than
570 \fIpassword\fR, \fIcram-md5\fR, \fIntlm\fR or \fIotp\fR suppresses fetchmail's
571 normal inquiry for a password. Specify \fIssh\fR when you are using
572 an end-to-end secure connection such as an ssh tunnel; specify
573 \fRgssapi\fR or \fBkerberos_v4\fR if you are using a protocol variant
574 that employs GSSAPI or K4. Choosing KPOP protocol automatically
575 selects Kerberos authentication. This option does not work with ETRN.
576 .SS Miscellaneous Options
578 .B \-f <pathname>, --fetchmailrc <pathname>
579 Specify a non-default name for the
581 run control file. The pathname argument must be either "-" (a single
582 dash, meaning to read the configuration from standard input) or a
583 filename. Unless the --version option is also on, a named file
584 argument must have permissions no more open than 0600 (u=rw,g=,o=) or
587 .B \-i <pathname>, --idfile <pathname>
589 Specify an alternate name for the .fetchids file used to save POP3
593 (Keyword: no rewrite)
596 edits RFC-822 address headers (To, From, Cc, Bcc, and Reply-To) in
597 fetched mail so that any mail IDs local to the server are expanded to
598 full addresses (@ and the mailserver hostname are appended). This enables
599 replies on the client to get addressed correctly (otherwise your
600 mailer might think they should be addressed to local users on the
601 client machine!). This option disables the rewrite. (This option is
602 provided to pacify people who are paranoid about having an MTA edit
603 mail headers and want to know they can prevent it, but it is generally
604 not a good idea to actually turn off rewrite.)
605 When using ETRN or ODMR, the rewrite option is ineffective.
607 .B -E <line>, --envelope <line>
609 This option changes the header
611 assumes will carry a copy of the mail's envelope address. Normally
612 this is `X-Envelope-To' but as this header is not standard, practice
613 varies. See the discussion of multidrop address handling below. As a
614 special case, `envelope "Received"' enables parsing of sendmail-style
615 Received lines. This is the default, and it should not be necessary
616 unless you have globally disabled Received parsing with `no envelope'
617 in the \fI.fetchmailrc\fR file.
619 .B -Q <prefix>, --qvirtual <prefix>
621 The string prefix assigned to this option will be removed from the user
622 name found in the header specified with the \fIenvelope\fR option
623 (\fIbefore\fR doing multidrop name mapping or localdomain checking,
624 if either is applicable). This option is useful if you are using
626 to collect the mail for an entire domain and your ISP (or your mail
627 redirection provider) is using qmail.
628 One of the basic features of qmail is the
632 message header. Whenever qmail delivers a message to a local mailbox
633 it puts the username and hostname of the envelope recipient on this
634 line. The major reason for this is to prevent mail loops. To set up
635 qmail to batch mail for a disconnected site the ISP-mailhost will have
636 normally put that site in its `Virtualhosts' control file so it will
637 add a prefix to all mail addresses for this site. This results in mail
638 .\" The \&@\& tries to stop HTML converters from making a mailto URL here.
639 sent to 'username\&@\&userhost.userdom.dom.com' having a
640 \&`Delivered-To:' line of the form:
642 Delivered-To: mbox-userstr-username\&@\&userhost.userdom.dom.com
644 The ISP can make the 'mbox-userstr-' prefix anything they choose
645 but a string matching the user host name is likely.
646 By using the option `envelope Delivered-To:' you can make fetchmail reliably
647 identify the original envelope recipient, but you have to strip the
648 `mbox-userstr-' prefix to deliver to the correct user.
649 This is what this option is for.
654 file, interpret any command-line options specified, and dump a
655 configuration report to standard output. The configuration report is
656 a data structure assignment in the language Python. This option
657 is meant to be used with an interactive
663 .SH USER AUTHENTICATION AND ENCRYPTION
664 All modes except ETRN require authentication of the client.
665 Normal user authentication in
667 is very much like the authentication mechanism of
669 The correct user-id and password depend upon the underlying security
670 system at the mailserver.
672 If the mailserver is a Unix machine on which you have an ordinary user
673 account, your regular login name and password are used with
675 If you use the same login name on both the server and the client machines,
676 you needn't worry about specifying a user-id with the
679 the default behavior is to use your login name on the client machine as the
680 user-id on the server machine. If you use a different login name
681 on the server machine, specify that login name with the
683 option. e.g. if your login name is 'jsmith' on a machine named 'mailgrunt',
688 fetchmail -u jsmith mailgrunt
690 The default behavior of
692 is to prompt you for your mailserver password before the connection is
693 established. This is the safest way to use
695 and ensures that your password will not be compromised. You may also specify
696 your password in your
698 file. This is convenient when using
700 in daemon mode or with scripts.
702 If you do not specify a password, and
704 cannot extract one from your
706 file, it will look for a
708 file in your home directory before requesting one interactively; if an
709 entry matching the mailserver is found in that file, the password will
710 be used. Fetchmail first looks for a match on poll name; if it finds none,
711 it checks for a match on via name. See the
713 man page for details of the syntax of the
715 file. (This feature may allow you to avoid duplicating password
716 information in more than one file.)
718 On mailservers that do not provide ordinary user accounts, your user-id and
719 password are usually assigned by the server administrator when you apply for
720 a mailbox on the server. Contact your server administrator if you don't know
721 the correct user-id and password for your mailbox account.
723 Early versions of POP3 (RFC1081, RFC1225) supported a crude form of
724 independent authentication using the
726 file on the mailserver side. Under this RPOP variant, a fixed
727 per-user ID equivalent to a password was sent in clear over a link to
728 a reserved port, with the command RPOP rather than PASS to alert the
729 server that it should do special checking. RPOP is supported
732 (you can specify `protocol RPOP' to have the program send `RPOP'
733 rather than `PASS') but its use is strongly discouraged. This
734 facility was vulnerable to spoofing and was withdrawn in RFC1460.
736 RFC1460 introduced APOP authentication. In this variant of POP3,
737 you register an APOP password on your server host (the program
738 to do this with on the server is probably called \fIpopauth\fR(8)). You
739 put the same password in your
743 logs in, it sends a cryptographically secure hash of your password and
744 the server greeting time to the server, which can verify it by
745 checking its authorization database.
747 If your \fIfetchmail\fR was built with Kerberos support and you specify
748 Kerberos authentication (either with --auth or the \fI.fetchmailrc\fR
749 option \fBauthenticate kerberos_v4\fR) it will try to get a Kerberos
750 ticket from the mailserver at the start of each query. Note: if
751 either the pollnane or via name is `hesiod', fetchmail will try to use
752 Hesiod to look up the mailserver.
754 If you use POP3 or IMAP with GSSAPI authentication, \fIfetchmail\fR will
755 expect the server to have RFC1731- or RFC1734-conformant GSSAPI
756 capability, and will use it. Currently this has only been tested over
757 Kerberos V, so you're expected to already have a ticket-granting
758 ticket. You may pass a username different from your principal name
759 using the standard \fB--user\fR command or by the \fI.fetchmailrc\fR
762 If your IMAP daemon returns the PREAUTH response in its greeting line,
763 fetchmail will notice this and skip the normal authentication step.
764 This can be useful, e.g. if you start imapd explicitly using ssh.
765 In this case you can declare the authentication value `ssh' on that
766 site entry to stop \fI.fetchmail\fR from asking you for a password
769 If you are using POP3, and the server issues a one-time-password
770 challenge conforming to RFC1938, \fIfetchmail\fR will use your
771 password as a pass phrase to generate the required response. This
772 avoids sending secrets over the net unencrypted.
774 Compuserve's RPA authentication (similar to APOP) is supported. If you
775 compile in the support, \fIfetchmail\fR will try to perform an RPA pass-phrase
776 authentication instead of sending over the password en clair if it
777 detects "@compuserve.com" in the hostname.
779 If you are using IMAP, Microsoft's NTLM authentication (used by Microsoft
780 Exchange) is supported. If you compile in the support, \fIfetchmail\fR
781 will try to perform an NTLM authentication (instead of sending over the
782 password en clair) whenever the server returns AUTH=NTLM in its
783 capability response. Specify a user option value that looks like
784 `user@domain': the part to the left of the @ will be passed as the
785 username and the part to the right as the NTLM domain.
787 If you are using IPsec, the -T (--netsec) option can be used to pass
788 an IP security request to be used when outgoing IP connections are
789 initialized. You can also do this using the `netsec' server option
790 in the .fetchmailrc file. In either case, the option value is a
791 string in the format accepted by the net_security_strtorequest()
792 function of the inet6_apps library.
794 You can access SSL encrypted services by specifying the --ssl option.
795 You can also do this using the "ssl" server option in the .fetchmailrc
796 file. With SSL encryption enabled, queries are initiated over a connection
797 after negotiating an SSL session. Some services, such as POP3 and IMAP,
798 have different well known ports defined for the SSL encrypted services.
799 The encrypted ports will be selected automatically when SSL is enabled and
800 no explicit port is specified.
802 When connecting to an SSL encrypted server, the server presents a certificate
803 to the client for validation. The certificate is checked to verify that
804 the common name in the certificate matches the name of the server being
805 contacted and that the effective and expiration dates in the certificate
806 indicate that it is currently valid. If any of these checks fail, a warning
807 message is printed, but the connection continues. The server certificate
808 does not need to be signed by any specific Certifying Authority and may
809 be a "self-signed" certificate.
811 Some SSL encrypted servers may request a client side certificate. A client
812 side public SSL certificate and private SSL key may be specified. If
813 requested by the server, the client certificate is sent to the server for
814 validation. Some servers may require a valid client certificate and may
815 refuse connections if a certificate is not provided or if the certificate
816 is not valid. Some servers may require client side certificates be signed
817 by a recognized Certifying Authority. The format for the key files and
818 the certificate files is that required by the underlying SSL libraries
819 (OpenSSL in the general case).
821 Finally, a word of care about the use of SSL: While above mentioned
822 setup with self-signed server certificates retrieved over the wires
823 can protect you from a passive eavesdropper it doesn't help against an
824 active attacker. It's clearly an improvement over sending the
825 passwords in clear but you should be aware that a man-in-the-middle
826 attack is trivially possible (in particular with tools such as dsniff,
827 http://www.monkey.org/~dugsong/dsniff/). Use of an ssh tunnel (see
828 below for some examples) is preferable if you care seriously about the
829 security of your mailbox.
833 .B --daemon <interval>
838 in daemon mode. You must specify a numeric argument which is a
839 polling interval in seconds.
843 puts itself in background and runs forever, querying each specified
844 host and then sleeping for the given polling interval.
850 will, therefore, poll all the hosts described in your
852 file (except those explicitly excluded with the `skip' verb) once
853 every fifteen minutes.
855 It is possible to set a polling interval
858 file by saying `set daemon <interval>', where <interval> is an
859 integer number of seconds. If you do this, fetchmail will always
860 start in daemon mode unless you override it with the command-line
861 option --daemon 0 or -d0.
863 Only one daemon process is permitted per user; in daemon mode,
865 makes a per-user lockfile to guarantee this.
867 Normally, calling fetchmail with a daemon in the background sends a
868 wakeup signal to the daemon, forcing it to poll mailservers
869 immediately. (The wakeup signal is SIGHUP if fetchmail is running as
870 root, SIGUSR1 otherwise.) The wakeup action also clears any `wedged'
871 flags indicating that connections have wedged due to failed
872 authentication or multiple timeouts.
876 will kill a running daemon process instead of waking it up (if there
879 notifies you). If the --quit option is the only command-line option,
880 that's all there is to it.
882 The quit option may also be mixed with other command-line options; its
883 effect is to kill any running daemon before doing what the other
884 options specify in combination with the rc file.
889 .B --logfile <filename>
890 option (keyword: set logfile) allows you to redirect status messages
891 emitted while detached into a specified logfile (follow the
892 option with the logfile name). The logfile is opened for append, so
893 previous messages aren't deleted. This is primarily useful for
894 debugging configurations.
898 option (keyword: set syslog) allows you to redirect status and error
899 messages emitted to the
901 system daemon if available.
902 Messages are logged with an id of \fBfetchmail\fR, the facility \fBLOG_MAIL\fR,
903 and priorities \fBLOG_ERR\fR, \fBLOG_ALERT\fR or \fBLOG_INFO\fR.
904 This option is intended for logging status and error messages which
905 indicate the status of the daemon and the results while fetching mail
907 Error messages for command line options and parsing the \fI.fetchmailrc\fR
908 file are still written to stderr, or to the specified log file.
911 option turns off use of
913 assuming it's turned on in the
923 or --nodetach option suppresses backgrounding and detachment of the
924 daemon process from its control terminal. This is primarily useful
925 for debugging. Note that this also causes the logfile option to be
926 ignored (though perhaps it shouldn't).
928 Note that while running in daemon mode polling a POP2 or IMAP2bis server,
929 transient errors (such as DNS failures or sendmail delivery refusals)
930 may force the fetchall option on for the duration of the next polling
931 cycle. This is a robustness feature. It means that if a message is
932 fetched (and thus marked seen by the mailserver) but not delivered
933 locally due to some transient error, it will be re-fetched during the
934 next poll cycle. (The IMAP logic doesn't delete messages until
935 they're delivered, so this problem does not arise.)
937 If you touch or change the
939 file while fetchmail is running in daemon mode, this will be detected
940 at the beginning of the next poll cycle. When a changed
942 is detected, fetchmail rereads it and restarts from scratch (using
943 exec(2); no state information is retained in the new instance). Note also
944 that if you break the
946 file's syntax, the new instance will softly and silently vanish away
949 .SH ADMINISTRATIVE OPTIONS
952 .B --postmaster <name>
953 option (keyword: set postmaster) specifies the last-resort username to
954 which multidrop mail is to be forwarded if no matching local recipient
955 can be found. Normally this is just the user who invoked fetchmail.
956 If the invoking user is root, then the default of this option is
957 the user `postmaster'. Setting postmaster to the empty string causes
958 such mail to be discarded.
962 option suppresses the normal action of bouncing errors back to the
963 sender in an RFC1894-conformant error message. If nobounce is on, the
964 message will go to the postmaster instead.
968 option (keyword: set invisible) tries to make fetchmail invisible.
969 Normally, fetchmail behaves like any other MTA would -- it generates a
970 Received header into each message describing its place in the chain of
971 transmission, and tells the MTA it forwards to that the mail came from
972 the machine fetchmail itself is running on. If the invisible option
973 is on, the Received header is suppressed and fetchmail tries to spoof
974 the MTA it forwards to into thinking it came directly from the
979 option (keyword: set showdots) forces fetchmail to show progress dots
980 even if the current tty is not stdout (for example logfiles).
981 Starting with fetchmail version 5.3.0,
982 progress dots are only shown on stdout by default.
986 option, you can ask fetchmail to add information to the Received
987 header on the form "polling {label} account {user}", where {label} is
988 the account label (from the specified rcfile, normally ~/.fetchmailrc)
989 and {user} is the username which is used to log on to the mail
990 server. This header can be used to make filtering email where no
991 useful header information is available and you want mail from
992 different accounts sorted into different mailboxes (this could, for
993 example, occur if you have an account on the same server running a
994 mailing list, and are subscribed to the list using that account). The
995 default is not adding any such header. In
997 this is called `tracepolls'.
999 .SH RETRIEVAL FAILURE MODES
1000 The protocols \fIfetchmail\fR uses to talk to mailservers are next to
1001 bulletproof. In normal operation forwarding to port 25, no message is
1002 ever deleted (or even marked for deletion) on the host until the SMTP
1003 listener on the client side has acknowledged to \fIfetchmail\fR that
1004 the message has been either accepted for delivery or rejected due to a
1007 When forwarding to an MDA, however, there is more possibility
1008 of error. Some MDAs are `safe' and reliably return a nonzero status
1009 on any delivery error, even one due to temporary resource limits.
1012 program is like this; so are most programs designed as mail transport
1017 These programs give back a reliable positive acknowledgement and
1018 can be used with the mda option with no risk of mail loss. Unsafe
1019 MDAs, though, may return 0 even on delivery failure. If this
1020 happens, you will lose mail.
1022 The normal mode of \fIfetchmail\fR is to try to download only `new'
1023 messages, leaving untouched (and undeleted) messages you have already
1024 read directly on the server (or fetched with a previous \fIfetchmail
1025 --keep\fR). But you may find that messages you've already read on the
1026 server are being fetched (and deleted) even when you don't specify
1027 --all. There are several reasons this can happen.
1029 One could be that you're using POP2. The POP2 protocol includes no
1030 representation of `new' or `old' state in messages, so \fIfetchmail\fR
1031 must treat all messages as new all the time. But POP2 is obsolete, so
1034 Under POP3, blame RFC1725. That version of the POP3 protocol
1035 specification removed the LAST command, and some POP servers follow it
1036 (you can verify this by invoking \fIfetchmail -v\fR to the mailserver
1037 and watching the response to LAST early in the query). The
1038 \fIfetchmail\fR code tries to compensate by using POP3's UID feature,
1039 storing the identifiers of messages seen in each session until the
1040 next session, in the \fI.fetchids\fR file. But this doesn't track
1041 messages seen with other clients, or read directly with a mailer on
1042 the host but not deleted afterward. A better solution would be to
1045 Another potential POP3 problem might be servers that insert messages
1046 in the middle of mailboxes (some VMS implementations of mail are
1047 rumored to do this). The \fIfetchmail\fR code assumes that new
1048 messages are appended to the end of the mailbox; when this is not true
1049 it may treat some old messages as new and vice versa. The only
1050 real fix for this problem is to switch to IMAP.
1052 Yet another POP3 problem is that if they can't make tempfiles in the
1053 user's home directory, some POP3 servers will hand back an
1054 undocumented response that causes fetchmail to spuriously report "No
1057 The IMAP code uses the presence or absence of the server flag \eSeen
1058 to decide whether or not a message is new. Under Unix, it counts on
1059 your IMAP server to notice the BSD-style Status flags set by mail user
1060 agents and set the \eSeen flag from them when appropriate. All Unix
1061 IMAP servers we know of do this, though it's not specified by the IMAP
1062 RFCs. If you ever trip over a server that doesn't, the symptom will
1063 be that messages you have already read on your host will look new to
1064 the server. In this (unlikely) case, only messages you fetched with
1065 \fIfetchmail --keep\fR will be both undeleted and marked old.
1067 In ETRN and ODMR modes, \fIfetchmail\fR does not actually retrieve messages;
1068 instead, it asks the server's SMTP listener to start a queue flush
1069 to the client via SMTP. Therefore it sends only undelivered messages.
1072 Many SMTP listeners allow administrators to set up `spam filters' that
1073 block unsolicited email from specified domains. A MAIL FROM or DATA line that
1074 triggers this feature will elicit an SMTP response which
1075 (unfortunately) varies according to the listener.
1079 return an error code of 571. This return value
1080 is blessed by RFC1893 as "Delivery not authorized, message refused".
1082 According to current drafts of the replacement for RFC821, the correct
1083 thing to return in this situation is 550 "Requested action not taken:
1084 mailbox unavailable" (the draft adds "[E.g., mailbox not found, no
1085 access, or command rejected for policy reasons].").
1089 MTA returns 501 "Syntax error in parameters or arguments", but will
1094 MTA runs 554 as an antispam response.
1098 code recognizes and discards the message on any of a list of responses
1099 that defaults to [571, 550, 501, 554] but can be set with the `antispam'
1100 option. This is one of the
1102 three circumstance under which fetchmail ever discards mail (the others
1103 are the 552 and 553 errors described below, and the suppression of
1104 multidropped messages with a message-ID already seen).
1108 is fetching from an IMAP server, the antispam response will be detected and
1109 the message rejected immediately after the headers have been fetched,
1110 without reading the message body. Thus, you won't pay for downloading
1111 spam message bodies.
1113 If the \fIspambounce\fR option is on, mail that is spam-blocked
1114 triggers an RFC1892 bounce message informing the originator that we do
1115 not accept mail from it.
1117 .SH SMTP/ESMTP ERROR HANDLING
1118 Besides the spam-blocking described above, fetchmail takes special
1119 actions on the following SMTP/ESMTP error responses
1121 452 (insufficient system storage)
1122 Leave the message in the server mailbox for later retrieval.
1124 552 (message exceeds fixed maximum message size)
1125 Delete the message from the server. Send bounce-mail to the originator.
1127 553 (invalid sending domain)
1128 Delete the message from the server. Send bounce-mail to the originator.
1130 Other errors trigger bounce mail back to the originator.
1132 .SH THE RUN CONTROL FILE
1133 The preferred way to set up fetchmail is to write a
1134 \&\fI.fetchmailrc\fR file in your home directory (you may do this
1135 directly, with a text editor, or indirectly via \fIfetchmailconf\fR).
1136 When there is a conflict between the command-line arguments and the
1137 arguments in this file, the command-line arguments take precedence.
1139 To protect the security of your passwords, when --version is not on
1140 your \fI~/.fetchmailrc\fR may not have more than 0600 (u=rw,g=,o=) permissions;
1142 will complain and exit otherwise.
1144 You may read the \fI.fetchmailrc\fR file as a list of commands to
1147 is called with no arguments.
1148 .SS Run Control Syntax
1150 Comments begin with a '#' and extend through the end of the line.
1151 Otherwise the file consists of a series of server entries or global
1152 option statements in a free-format, token-oriented syntax.
1154 There are four kinds of tokens: grammar keywords, numbers
1155 (i.e. decimal digit sequences), unquoted strings, and quoted strings.
1156 A quoted string is bounded by double quotes and may contain
1157 whitespace (and quoted digits are treated as a string). An unquoted
1158 string is any whitespace-delimited token that is neither numeric, string
1159 quoted nor contains the special characters `,', `;', `:', or `='.
1161 Any amount of whitespace separates tokens in server entries, but is
1162 otherwise ignored. You may use standard C-style escapes (\en, \et,
1163 \eb, octal, and hex) to embed non-printable characters or string
1164 delimiters in strings.
1166 Each server entry consists of one of the keywords `poll' or `skip',
1167 followed by a server name, followed by server options, followed by any
1168 number of user descriptions. Note: the most common cause of syntax
1169 errors is mixing up user and server options.
1171 For backward compatibility, the word `server' is a synonym for `poll'.
1173 You can use the noise keywords `and', `with',
1174 \&`has', `wants', and `options' anywhere in an entry to make
1175 it resemble English. They're ignored, but but can make entries much
1176 easier to read at a glance. The punctuation characters ':', ';' and
1177 \&',' are also ignored.
1180 The `poll' verb tells fetchmail to query this host when it is run with
1181 no arguments. The `skip' verb tells
1183 not to poll this host unless it is explicitly named on the command
1184 line. (The `skip' verb allows you to experiment with test entries
1185 safely, or easily disable entries for hosts that are temporarily down.)
1187 .SS Keyword/Option Summary
1188 Here are the legal options. Keyword suffixes enclosed in
1189 square brackets are optional. Those corresponding to command-line
1190 options are followed by `-' and the appropriate option letter.
1192 Here are the legal global options:
1196 Keyword Opt Function
1199 Set a background poll interval in seconds
1201 set postmaster \& T{
1202 Give the name of the last-resort mail recipient
1204 set no bouncemail \& T{
1205 Direct error mail to postmaster rather than sender
1207 set no spambounce \& T{
1211 Name of a file to dump error and status messages to
1214 Name of the file to store UID lists in
1217 Do error logging through syslog(3).
1220 Turn off error logging through syslog(3).
1222 set properties \& T{
1223 String value is ignored by fetchmail (may be used by extension scripts)
1227 Here are the legal server options:
1231 Keyword Opt Function
1234 Specify DNS name of mailserver, overriding poll name
1237 Specify protocol (case insensitive):
1238 POP2, POP3, IMAP, APOP, KPOP
1240 local[domains] \& T{
1241 Specify domain(s) to be regarded as local
1244 Specify TCP/IP service port
1246 auth[enticate] \& T{
1247 Set authentication type (default `password')
1250 Server inactivity timeout in seconds (default 300)
1253 Specify envelope-address header name
1256 Disable looking for envelope address
1259 Qmail virtual domain prefix to remove from user name
1262 Specify alternate DNS names of mailserver
1265 specify IP interface(s) that must be up for server poll to take place
1268 Specify IP address to monitor for activity
1271 Specify command through which to make server connections.
1274 Specify command through which to make listener connections.
1277 Enable DNS lookup for multidrop (default)
1280 Disable DNS lookup for multidrop
1283 Do comparison by IP address for multidrop
1286 Do comparison by name for multidrop (default)
1289 Force POP3 to use client-side UIDLs
1292 Turn off POP3 use of client-side UIDLs (default)
1295 Only check this site every N poll cycles; N is a numeric argument.
1298 Pass in IPsec security option request.
1301 Set Kerberos principal (only useful with imap and kerberos)
1305 Here are the legal user options:
1309 Keyword Opt Function
1312 Set remote user name
1313 (local user name if name followed by `here')
1316 Connect local and remote user names
1319 Connect local and remote user names
1322 Specify remote account password
1325 Connect to server over the specified base protocol using SSL encryption
1328 Specify file for client side public SSL certificate
1331 Specify file for client side private SSL key
1334 Force ssl protocol for connection
1337 Specify remote folder to query
1340 Specify smtp host(s) to forward to
1343 Specify domains for which mail should be fetched
1346 Specify the domain to be put in RCPT TO lines
1349 Specify the user and domain to be put in RCPT TO lines
1352 Specify what SMTP returns are interpreted as spam-policy blocks
1355 Specify MDA for local delivery
1358 Specify BSMTP batch file to append to
1361 Command to be executed before each connection
1364 Command to be executed after each connection
1367 Don't delete seen messages from server
1370 Flush all seen messages before querying
1373 Fetch all messages whether seen or not
1376 Rewrite destination addresses for reply (default)
1379 Strip carriage returns from ends of lines
1382 Force carriage returns at ends of lines
1385 Force BODY=8BITMIME to ESMTP listener
1388 Strip Status and X-Mozilla-Status lines out of incoming mail
1391 Strip Delivered-To lines out of incoming mail
1394 Convert quoted-printable to 8-bit in MIME messages
1397 Idle waiting for new messages after each poll (IMAP only)
1400 Delete seen messages from server (default)
1403 Don't flush all seen messages before querying (default)
1406 Retrieve only new messages (default)
1409 Don't rewrite headers
1412 Don't strip carriage returns (default)
1415 Don't force carriage returns at EOL (default)
1418 Don't force BODY=8BITMIME to ESMTP listener (default)
1421 Don't drop Status headers (default)
1423 no dropdelivered \& T{
1424 Don't drop Delivered-To headers (default)
1427 Don't convert quoted-printable to 8-bit in MIME messages (default)
1430 Don't idle waiting for new messages after each poll (IMAP only)
1433 Set message size limit
1436 Set message size warning interval
1439 Max # messages to forward in single connect
1442 Max # messages to fetch in single connect
1445 Perform an expunge on every #th message (IMAP and POP3 only)
1448 Add poll tracing information to the Received header
1451 String value is ignored by fetchmail (may be used by extension scripts)
1455 Remember that all user options must \fIfollow\fR all server options.
1457 In the .fetchmailrc file, the `envelope' string argument may be
1458 preceded by a whitespace-separated number. This number, if specified,
1459 is the number of such headers to skip (that is, an argument of 1
1460 selects the second header of the given type). This is sometime useful
1461 for ignoring bogus Received headers created by an ISP's local delivery
1463 .SS Keywords Not Corresponding To Option Switches
1465 The `folder' and `smtphost' options (unlike their command-line
1466 equivalents) can take a space- or comma-separated list of names
1469 All options correspond to the obvious command-line arguments, except
1470 the following: `via', `interval', `aka', `is', `to', `dns'/`no dns',
1471 `checkalias'/`no checkalias', `password', `preconnect', `postconnect',
1472 `localdomains', `stripcr'/`no stripcr', `forcecr'/`no forcecr',
1473 `pass8bits'/`no pass8bits' `dropstatus/no dropstatus',
1474 `dropdelivered/no dropdelivered', `mimedecode/no mimedecode', `idle/no
1475 idle', and `no envelope'.
1477 The `via' option is for if you want to have more
1478 than one configuration pointing at the same site. If it is present,
1479 the string argument will be taken as the actual DNS name of the
1480 mailserver host to query.
1481 This will override the argument of poll, which can then simply be a
1482 distinct label for the configuration (e.g. what you would give on the
1483 command line to explicitly query this host).
1485 The `interval' option (which takes a numeric argument) allows you to poll a
1486 server less frequently than the basic poll interval. If you say
1487 \&`interval N' the server this option is attached to will only be
1488 queried every N poll intervals.
1490 The `is' or `to' keywords associate the following local (client)
1491 name(s) (or server-name to client-name mappings separated by =) with
1492 the mailserver user name in the entry. If an is/to list has `*' as
1493 its last name, unrecognized names are simply passed through.
1495 A single local name can be used to support redirecting your mail when
1496 your username on the client machine is different from your name on the
1497 mailserver. When there is only a single local name, mail is forwarded
1498 to that local username regardless of the message's Received, To, Cc,
1499 and Bcc headers. In this case
1501 never does DNS lookups.
1503 When there is more than one local name (or name mapping) the
1504 \fIfetchmail\fR code does look at the Received, To, Cc, and Bcc
1505 headers of retrieved mail (this is `multidrop mode'). It looks for
1506 addresses with hostname parts that match your poll name or your `via',
1507 `aka' or `localdomains' options, and usually also for hostname parts
1508 which DNS tells it are aliases of the mailserver. See the discussion
1509 of `dns', `checkalias', `localdomains', and `aka' for details on how
1510 matching addresses are handled.
1512 If \fIfetchmail\fR cannot match any mailserver usernames or
1513 localdomain addresses, the mail will be bounced.
1514 Normally it will be bounced to the sender, but if `nobounce' is on
1515 it will go to the postmaster (which in turn defaults to being the
1518 The `dns' option (normally on) controls the way addresses from
1519 multidrop mailboxes are checked. On, it enables logic to check each
1520 host address that doesn't match an `aka' or `localdomains' declaration
1521 by looking it up with DNS. When a mailserver username is recognized
1522 attached to a matching hostname part, its local mapping is added to
1523 the list of local recipients.
1525 The `checkalias' option (normally off) extends the lookups performed
1526 by the `dns' keyword in multidrop mode, providing a way to cope with
1527 remote MTAs that identify themselves using their canonical name, while
1528 they're polled using an alias.
1529 When such a server is polled, checks to extract the envelope address
1532 reverts to delivery using the To/Cc/Bcc headers (See below
1533 `Header vs. Envelope addresses').
1534 Specifying this option instructs
1536 to retrieve all the IP addresses associated with both the poll name
1537 and the name used by the remote MTA and to do a comparison of the IP
1538 addresses. This comes in handy in situations where the remote server
1539 undergoes frequent canonical name changes, that would otherwise
1540 require modifications to the rcfile. `checkalias' has no effect if
1541 `no dns' is specified in the rcfile.
1543 The `aka' option is for use with multidrop mailboxes. It allows you
1544 to pre-declare a list of DNS aliases for a server. This is an
1545 optimization hack that allows you to trade space for speed. When
1547 while processing a multidrop mailbox, grovels through message headers
1548 looking for names of the mailserver, pre-declaring common ones can
1549 save it from having to do DNS lookups. Note: the names you give
1550 as arguments to `aka' are matched as suffixes -- if you specify
1551 (say) `aka netaxs.com', this will match not just a hostnamed
1552 netaxs.com, but any hostname that ends with `.netaxs.com'; such as
1553 (say) pop3.netaxs.com and mail.netaxs.com.
1555 The `localdomains' option allows you to declare a list of domains
1556 which fetchmail should consider local. When fetchmail is parsing
1557 address lines in multidrop modes, and a trailing segment of a host
1558 name matches a declared local domain, that address is passed through
1559 to the listener or MDA unaltered (local-name mappings are \fInot\fR
1562 If you are using `localdomains', you may also need to specify \&`no
1563 envelope', which disables \fIfetchmail\fR's normal attempt to deduce
1564 an envelope address from the Received line or X-Envelope-To header or
1565 whatever header has been previously set by `envelope'. If you set `no
1566 envelope' in the defaults entry it is possible to undo that in
1567 individual entries by using `envelope <string>'. As a special case,
1568 \&`envelope "Received"' restores the default parsing of
1571 The \fBpassword\fR option requires a string argument, which is the password
1572 to be used with the entry's server.
1574 The `preconnect' keyword allows you to specify a shell command to be
1575 executed just before each time
1577 establishes a mailserver connection. This may be useful if you are
1578 attempting to set up secure POP connections with the aid of
1580 If the command returns a nonzero status, the poll of that mailserver
1583 Similarly, the `postconnect' keyword similarly allows you to specify a
1584 shell command to be executed just after each time a mailserver
1585 connection is taken down.
1587 The `forcecr' option controls whether lines terminated by LF only are
1588 given CRLF termination before forwarding. Strictly speaking RFC821
1589 requires this, but few MTAs enforce the requirement it so this option
1590 is normally off (only one such MTA, qmail, is in significant use at
1593 The `stripcr' option controls whether carriage returns are stripped
1594 out of retrieved mail before it is forwarded. It is normally not
1595 necessary to set this, because it defaults to `on' (CR stripping
1596 enabled) when there is an MDA declared but `off' (CR stripping
1597 disabled) when forwarding is via SMTP. If `stripcr' and `forcecr' are
1598 both on, `stripcr' will override.
1600 The `pass8bits' option exists to cope with Microsoft mail programs that
1601 stupidly slap a "Content-Transfer-Encoding: 7bit" on everything. With
1602 this option off (the default) and such a header present,
1604 declares BODY=7BIT to an ESMTP-capable listener; this causes problems for
1605 messages actually using 8-bit ISO or KOI-8 character sets, which will
1606 be garbled by having the high bits of all characters stripped. If
1607 \&`pass8bits' is on,
1609 is forced to declare BODY=8BITMIME to any ESMTP-capable listener. If
1610 the listener is 8-bit-clean (as all the major ones now are) the right
1611 thing will probably result.
1613 The `dropstatus' option controls whether nonempty Status and
1614 X-Mozilla-Status lines are retained in fetched mail (the default) or
1615 discarded. Retaining them allows your MUA to see what messages (if
1616 any) were marked seen on the server. On the other hand, it can
1617 confuse some new-mail notifiers, which assume that anything with a
1618 Status line in it has been seen. (Note: the empty Status lines
1619 inserted by some buggy POP servers are unconditionally discarded.)
1621 The `dropdelivered' option controls wether Delivered-To headers will
1622 be kept in fetched mail (the default) or discarded. These headers are
1623 added by Qmail and Postfix mailservers in order to avoid mail loops but
1624 may get in your way if you try to "mirror" a mailserver within the same
1625 domain. Use with caution.
1627 The `mimedecode' option controls whether MIME messages using the
1628 quoted-printable encoding are automatically converted into pure 8-bit
1629 data. If you are delivering mail to an ESMTP-capable, 8-bit-clean
1630 listener (that includes all of the major MTAs like sendmail), then
1631 this will automatically convert quoted-printable message headers and
1632 data into 8-bit data, making it easier to understand when reading
1633 mail. If your e-mail programs know how to deal with MIME messages,
1634 then this option is not needed. The mimedecode option is off by
1635 default, because doing RFC2047 conversion on headers throws away
1636 character-set information and can lead to bad results if the encoding
1637 of the headers differs from the body encoding.
1639 The `idle' option is usable only with IMAP servers supporting the
1640 RFC2177 IDLE command extension. If it is enabled, and fetchmail
1641 detects that IDLE is supported, an IDLE will be issued at the end
1642 of each poll. This will tell the IMAP server to hold the connection
1643 open and notify the client when new mail is available. If you need to
1644 poll a link frequently, IDLE can save bandwidth by eliminating TCP/IP
1645 connects and LOGIN/LOGOUT sequences. On the other hand, an IDLE
1646 connection will eat almost all of your fetchmail's time, because it
1647 will never drop the connection and allow other pools to occur unless
1648 the server times out the IDLE. It also doesn't work with multiple
1649 folders; only the first folder will ever be polled.
1651 The `properties' option is an extension mechanism. It takes a string
1652 argument, which is ignored by fetchmail itself. The string argument may be
1653 used to store configuration information for scripts which require it.
1654 In particular, the output of `--configdump' option will make properties
1655 associated with a user entry readily available to a Python script.
1657 .SS Miscellaneous Run Control Options
1658 The words `here' and `there' have useful English-like
1659 significance. Normally `user eric is esr' would mean that
1660 mail for the remote user `eric' is to be delivered to `esr',
1661 but you can make this clearer by saying `user eric there is esr here',
1662 or reverse it by saying `user esr here is eric there'
1664 Legal protocol identifiers for use with the `protocol' keyword are:
1675 Legal authentication types are `any', `password', `kerberos', 'kereberos_v5'
1676 and `gssapi', `cram-md5', `otp', `ntlm', `ssh`.
1677 The `password' type specifies authentication by normal transmission of a
1678 password (the password may be plaintext or subject to
1679 protocol-specific encryption as in APOP); `kerberos' tells
1680 \fIfetchmail\fR to try to get a Kerberos ticket at the start of each
1681 query instead, and send an arbitrary string as the password; and
1682 `gssapi' tells fetchmail to use GSSAPI authentication. See the description
1683 of the `auth' keyword for more.
1685 Specifying `kpop' sets POP3 protocol over port 1109 with Kerberos V4
1686 authentication. These defaults may be overridden by later options.
1688 There are currently four global option statements; `set logfile'
1689 followed by a string sets the same global specified by --logfile. A
1690 command-line --logfile option will override this. Also, `set daemon'
1691 sets the poll interval as --daemon does. This can be overridden by a
1692 command-line --daemon option; in particular --daemon 0 can be used to
1693 force foreground operation. The `set postmaster' statement sets the
1694 address to which multidrop mail defaults if there are no local
1695 matches. Finally, `set syslog' sends log messages to syslogd(8).
1697 .SH INTERACTION WITH RFC 822
1698 When trying to determine the originating address of a message,
1699 fetchmail looks through headers in the following order:
1702 Resent-Sender: (ignored if it doesn't contain an @ or !)
1703 Sender: (ignored if it doesn't contain an @ or !)
1709 The originating address is used for logging, and to set the MAIL FROM
1710 address when forwarding to SMTP. This order is intended to cope
1711 gracefully with receiving mailing list messages in multidrop mode. The
1712 intent is that if a local address doesn't exist, the bounce message
1713 won't be returned blindly to the author or to the list itself, but
1714 rather to the list manager (which is less annoying).
1716 In multidrop mode, destination headers are processed as follows:
1717 First, fetchmail looks for the Received: header (or whichever one is
1718 specified by the `envelope' option) to determine the local
1719 recipient address. If the mail is addressed to more than one recipient,
1720 the Received line won't contain any information regarding recipient addresses.
1722 Then fetchmail looks for the Resent-To:, Resent-Cc:, and Resent-Bcc:
1723 lines. If they exists, they should contain the final recipients and
1724 have precedence over their To:/Cc:/Bcc: counterparts. If the Resent-*
1725 lines doesn't exist, the To:, Cc:, Bcc: and Apparently-To: lines are
1726 looked for. (The presence of a Resent-To: is taken to imply that the
1727 person referred by the To: address has already received the original
1730 .SH CONFIGURATION EXAMPLES
1731 Note that although there are password declarations in a good many
1732 of the examples below, this is mainly for illustrative purposes.
1733 We recommend stashing account/password pairs in your $HOME/.netrc
1734 file, where they can be used not just by fetchmail but by ftp(1) and
1740 poll SERVERNAME protocol PROTOCOL username NAME password PASSWORD
1746 poll pop.provider.net protocol pop3 username "jsmith" password "secret1"
1749 Or, using some abbreviations:
1752 poll pop.provider.net proto pop3 user "jsmith" password "secret1"
1755 Multiple servers may be listed:
1758 poll pop.provider.net proto pop3 user "jsmith" pass "secret1"
1759 poll other.provider.net proto pop2 user "John.Smith" pass "My^Hat"
1762 Here's a version of those two with more whitespace and some noise words:
1765 poll pop.provider.net proto pop3
1766 user "jsmith", with password secret1, is "jsmith" here;
1767 poll other.provider.net proto pop2:
1768 user "John.Smith", with password "My^Hat", is "John.Smith" here;
1771 This version is much easier to read and doesn't cost significantly
1772 more (parsing is done only once, at startup time).
1775 If you need to include whitespace in a parameter string, enclose the
1776 string in double quotes. Thus:
1779 poll mail.provider.net with proto pop3:
1780 user "jsmith" there has password "u can't krak this"
1781 is jws here and wants mda "/bin/mail"
1784 You may have an initial server description headed by the keyword
1785 `defaults' instead of `poll' followed by a name. Such a record
1786 is interpreted as defaults for all queries to use. It may be overwritten
1787 by individual server descriptions. So, you could write:
1792 poll pop.provider.net
1794 poll mail.provider.net
1795 user "jjsmith" there has password "secret2"
1798 It's possible to specify more than one user per server (this is only
1799 likely to be useful when running fetchmail in daemon mode as root).
1800 The `user' keyword leads off a user description, and every user specification
1801 in a multi-user entry must include it. Here's an example:
1804 poll pop.provider.net proto pop3 port 3111
1805 user "jsmith" with pass "secret1" is "smith" here
1806 user jones with pass "secret2" is "jjones" here keep
1809 This associates the local username `smith' with the pop.provider.net
1810 username `jsmith' and the local username `jjones' with the
1811 pop.provider.net username `jones'. Mail for `jones' is kept on the
1812 server after download.
1814 Here's what a simple retrieval configuration for a multi-drop mailbox
1818 poll pop.provider.net:
1819 user maildrop with pass secret1 to golux 'hurkle'='happy' snark here
1822 This says that the mailbox of account `maildrop' on the server is a
1823 multi-drop box, and that messages in it should be parsed for the
1824 server user names `golux', `hurkle', and `snark'. It further
1825 specifies that `golux' and `snark' have the same name on the
1826 client as on the server, but mail for server user `hurkle' should be
1827 delivered to client user `happy'.
1829 Here's an example of another kind of multidrop connection:
1832 poll pop.provider.net localdomains loonytoons.org toons.org:
1833 user maildrop with pass secret1 to * here
1836 This also says that the mailbox of account `maildrop' on the server is
1837 a multi-drop box. It tells fetchmail that any address in the
1838 loonytoons.org or toons.org domains (including subdomain addresses like
1839 `joe@daffy.loonytoons.org') should be passed through to the local SMTP
1840 listener without modification. Be careful of mail loops if you do this!
1842 Here's an example configuration using ssh and the plugin option. The
1843 queries are made directly on the stdin and stdout of imapd via ssh.
1844 Note that in this setup, IMAP authentication can be skipped.
1847 poll mailhost.net with proto imap:
1848 plugin "ssh %h /usr/sbin/imapd" auth ssh;
1849 user esr is esr here
1852 .SH THE USE AND ABUSE OF MULTIDROP MAILBOXES
1853 Use the multiple-local-recipients feature with caution -- it can bite.
1854 All multidrop features are ineffective in ETRN and ODMR modes.
1856 Also, note that in multidrop mode duplicate mails are suppressed. A
1857 piece of mail is considered duplicate if it has the same message-ID as
1858 the message immediately preceding and more than one addressee. Such
1859 runs of messages may be generated when copies of a message addressed
1860 to multiple users are delivered to a multidrop box.
1862 .SS Header vs. Envelope addresses
1863 The fundamental problem is that by having your mailserver toss several
1864 peoples' mail in a single maildrop box, you may have thrown away
1865 potentially vital information about who each piece of mail was
1866 actually addressed to (the `envelope address', as opposed to the
1867 header addresses in the RFC822 To/Cc/Bcc headers). This `envelope
1868 address' is the address you need in order to reroute mail properly.
1872 can deduce the envelope address. If the mailserver MTA is
1874 and the item of mail had just one recipient, the MTA will have written
1875 a `by/for' clause that gives the envelope addressee into its Received
1876 header. But this doesn't work reliably for other MTAs, nor if there is
1877 more than one recipient. By default, \fIfetchmail\fR looks for
1878 envelope addresses in these lines; you can restore this default with
1879 -E "Received" or \&`envelope Received'.
1881 Alternatively, some SMTP listeners and/or mail servers insert a header
1882 in each message containing a copy of the envelope addresses. This
1883 header (when it exists) is often `X-Envelope-To'. Fetchmail's
1884 assumption about this can be changed with the -E or `envelope' option.
1885 Note that writing an envelope header of this kind exposes the names of
1886 recipients (including blind-copy recipients) to all receivers of the
1887 messages; it is therefore regarded by some administrators as a
1888 security/privacy problem.
1890 A slight variation of the `X-Envelope-To' header is the `Delivered-To' put
1891 by qmail to avoid mail loops. It will probably prefix the user name with a
1892 string that normally matches the user's domain. To remove this prefix you
1893 can use the -Q or `qvirtual' option.
1895 Sometimes, unfortunately, neither of these methods works. When they
1896 all fail, fetchmail must fall back on the contents of To/Cc/Bcc
1897 headers to try to determine recipient addressees -- and these are not
1898 reliable. In particular, mailing-list software often ships mail with
1899 only the list broadcast address in the To header.
1903 cannot deduce a recipient address that is local, and the intended
1904 recipient address was anyone other than fetchmail's invoking user,
1905 mail will get lost. This is what makes the multidrop feature risky.
1907 A related problem is that when you blind-copy a mail message, the Bcc
1908 information is carried \fIonly\fR as envelope address (it's not put
1909 in the headers fetchmail can see unless there is an X-Envelope
1910 header). Thus, blind-copying to someone who gets mail over a
1911 fetchmail link will fail unless the the mailserver host routinely
1912 writes X-Envelope or an equivalent header into messages in your maildrop.
1914 .SS Good Ways To Use Multidrop Mailboxes
1915 Multiple local names can be used to administer a mailing list from the
1916 client side of a \fIfetchmail\fR collection. Suppose your name is
1917 \&`esr', and you want to both pick up your own mail and maintain a mailing
1918 list called (say) "fetchmail-friends", and you want to keep the alias
1919 list on your client machine.
1921 On your server, you can alias \&`fetchmail-friends' to `esr'; then, in
1922 your \fI.fetchmailrc\fR, declare \&`to esr fetchmail-friends here'.
1923 Then, when mail including `fetchmail-friends' as a local address
1924 gets fetched, the list name will be appended to the list of
1925 recipients your SMTP listener sees. Therefore it will undergo alias
1926 expansion locally. Be sure to include `esr' in the local alias
1927 expansion of fetchmail-friends, or you'll never see mail sent only to
1928 the list. Also be sure that your listener has the "me-too" option set
1929 (sendmail's -oXm command-line option or OXm declaration) so your name
1930 isn't removed from alias expansions in messages you send.
1932 This trick is not without its problems, however. You'll begin to see
1933 this when a message comes in that is addressed only to a mailing list
1934 you do \fInot\fR have declared as a local name. Each such message
1935 will feature an `X-Fetchmail-Warning' header which is generated
1936 because fetchmail cannot find a valid local name in the recipient
1937 addresses. Such messages default (as was described above) to being
1938 sent to the local user running
1940 but the program has no way to know that that's actually the right thing.
1942 .SS Bad Ways To Abuse Multidrop Mailboxes
1943 Multidrop mailboxes and
1945 serving multiple users in daemon mode do not mix. The problem, again, is
1946 mail from mailing lists, which typically does not have an individual
1947 recipient address on it. Unless
1949 can deduce an envelope address, such mail will only go to the account
1950 running fetchmail (probably root). Also, blind-copied users are very
1951 likely never to see their mail at all.
1953 If you're tempted to use
1955 to retrieve mail for multiple users from a single mail drop via POP or
1956 IMAP, think again (and reread the section on header and envelope
1957 addresses above). It would be smarter to just let the mail sit in the
1958 mailserver's queue and use fetchmail's ETRN or ODMR modes to trigger
1959 SMTP sends periodically (of course, this means you have to poll more
1960 frequently than the mailserver's expiry period). If you can't arrange
1961 this, try setting up a UUCP feed.
1963 If you absolutely \fImust\fR use multidrop for this purpose, make sure
1964 your mailserver writes an envelope-address header that fetchmail can
1965 see. Otherwise you \fIwill\fR lose mail and it \fIwill\fR come back
1968 .SS Speeding Up Multidrop Checking
1969 Normally, when multiple users are declared
1971 extracts recipient addresses as described above and checks each host
1972 part with DNS to see if it's an alias of the mailserver. If so, the
1973 name mappings described in the to ... here declaration are done and
1974 the mail locally delivered.
1976 This is the safest but also slowest method. To speed it up,
1977 pre-declare mailserver aliases with `aka'; these are checked before
1978 DNS lookups are done. If you're certain your aka list contains
1980 DNS aliases of the mailserver (and all MX names pointing at it)
1981 you can declare `no dns' to suppress DNS lookups entirely and
1982 \fIonly\fR match against the aka list.
1985 To facilitate the use of
1987 in shell scripts, an exit code is returned to give an indication
1988 of what occurred during a given connection.
1990 The exit codes returned by
1994 One or more messages were successfully retrieved (or, if the -c option
1995 was selected, were found waiting but not retrieved).
1997 There was no mail awaiting retrieval. (There may have been old mail still
1998 on the server but not selected for retrieval.)
2000 An error was encountered when attempting to open a socket to retrieve
2001 mail. If you don't know what a socket is, don't worry about it --
2002 just treat this as an 'unrecoverable error'. This error can also be
2003 because a protocol fetchmail wants to use is not listed in /etc/services.
2005 The user authentication step failed. This usually means that a bad
2006 user-id, password, or APOP id was specified. Or it may mean that you
2007 tried to run fetchmail under circumstances where it did not have
2008 standard input attached to a terminal and could not prompt for a
2011 Some sort of fatal protocol error was detected.
2013 There was a syntax error in the arguments to
2016 The run control file had bad permissions.
2018 There was an error condition reported by the server. Can also
2021 timed out while waiting for the server.
2023 Client-side exclusion error. This means
2025 either found another copy of itself already running, or failed in such
2026 a way that it isn't sure whether another copy is running.
2028 The user authentication step failed because the server responded "lock
2029 busy". Try again after a brief pause! This error is not implemented
2030 for all protocols, nor for all servers. If not implemented for your
2031 server, "3" will be returned instead, see above. May be returned when
2032 talking to qpopper or other servers that can respond with "lock busy"
2033 or some similar text containing the word "lock".
2037 run failed while trying to do an SMTP port open or transaction.
2039 Fatal DNS error. Fetchmail encountered an error while performing
2040 a DNS lookup at startup and could not proceed.
2042 BSMTP batch file could not be opened.
2044 Poll terminated by a fetch limit (see the --fetchlimit option).
2046 Server busy indication.
2048 Internal error. You should see a message on standard error with
2053 queries more than one host, return status is 0 if \fIany\fR query
2054 successfully retrieved mail. Otherwise the returned error status is
2055 that of the last host queried.
2060 default run control file
2063 default location of file associating hosts with last message IDs seen
2064 (used only with newer RFC1725-compliant POP3 servers supporting the
2068 lock file to help prevent concurrent runs (non-root mode).
2071 your FTP run control file, which (if present) will be searched for
2072 passwords as a last resort before prompting for one interactively.
2074 /var/run/fetchmail.pid
2075 lock file to help prevent concurrent runs (root mode, Linux systems).
2078 lock file to help prevent concurrent runs (root mode, systems without /var/run).
2081 If the FETCHMAILUSER variable is set, it is used as the name of the
2082 calling user (default local name) for purposes such as mailing error
2083 notifications. Otherwise, if either the LOGNAME or USER variable is
2084 correctly set (e.g. the corresponding UID matches the session user ID)
2085 then that name is used as the default local name. Otherwise
2086 \fBgetpwuid\fR(3) must be able to retrieve a password entry for the
2087 session ID (this elaborate logic is designed to handle the case of
2088 multiple names per userid gracefully).
2090 If the environment variable FETCHMAILHOME is set to a valid and
2091 existing directory name, the .fetchmailrc and .fetchids and
2092 \&.fetchmail.pid files are put there instead of in the invoking user's
2093 home directory (and lose the leading dots on theirt names). The
2094 \&.netrc file is looked for in the the invoking user's home directory
2095 regardless of FETCHMAILHOME's setting.
2100 daemon is running as root, SIGHUP wakes it up from its sleep phase and
2101 forces a poll of all non-skipped servers (this is in accordance with
2102 the usual conventions for system daemons).
2106 is running in daemon mode as non-root, use SIGUSR1 to wake it (this is
2107 so SIGHUP due to logout can retain the default action of killing it).
2111 in foreground while a background fetchmail is running will do
2112 whichever of these is appropriate to wake it up.
2114 .SH BUGS AND KNOWN PROBLEMS
2115 The mda and plugin options interact badly. In order to collect error
2116 status from the MDA, fetchmail has to change its normal signal
2117 handling so that dead plugin processes don't get reaped until the end
2118 of the poll cycle. This can cause resource starvation if too many
2119 zombies accumulate. So either don't deliver to a MDA using plugins or
2120 risk being overrun by an army of undead.
2122 The RFC822 address parser used in multidrop mode chokes on some
2123 @-addresses that are technically legal but bizarre. Strange uses of
2124 quoting and embedded comments are likely to confuse it.
2126 In a message with multiple envelope headers, only the last one
2127 processed will be visible to fetchmail. To get around this, use a
2128 mailserver-side filter that consolidates the contents of all envelope
2129 headers into a single one (procmail, mailagent, or maildrop can be
2130 programmed to do this fairly easily).
2132 Use of some of these protocols requires that the program send
2133 unencrypted passwords over the TCP/IP connection to the mailserver.
2134 This creates a risk that name/password pairs might be snaffled with a
2135 packet sniffer or more sophisticated monitoring software. Under Linux
2136 and FreeBSD, the --interface option can be used to restrict polling to
2137 availability of a specific interface device with a specific local or
2138 remote IP address, but snooping is still possible if (a) either host
2139 has a network device that can be opened in promiscuous mode, or (b)
2140 the intervening network link can be tapped. We recommend the use of
2142 tunnelling to not only shroud your passwords but encrypt the entire
2145 Use of the %F or %T escapes in an mda option could open a security
2146 hole, because they pass text manipulable by an attacker to a shell
2147 command. Potential shell characters are replaced by `_' before
2148 execution. The hole is further reduced by the fact that fetchmail
2149 temporarily discards any suid privileges it may have while running the
2150 MDA. For maximum safety, however, don't use an mda command containing
2151 %F or %T when fetchmail is run from the root account itself.
2153 Fetchmail's method of sending bouncemail and spam bounces requires that
2154 port 25 of localhost be available for sending mail via SMTP.
2158 while a background instance is running and break the syntax, the
2159 background instance will die silently. Unfortunately, it can't
2160 die noisily because we don't yet know whether syslog should be enabled.
2162 The -f - option (reading a configuration from stdin) is incompatible
2163 with the plugin option.
2165 The UIDL code is generally flaky and tends to lose its state on errors
2166 and line drops (so that old messages are re-seen). If this happens to
2167 you, switch to IMAP4.
2169 The `principal' option only handles Kerberos IV, not V.
2171 Send comments, bug reports, gripes, and the like to the
2172 fetchmail-friends list <fetchmail-friends@lists.ccil.org>. An HTML FAQ is
2173 available at the fetchmail home page; surf to
2174 http://www.tuxedo.org/~esr/fetchmail or do a WWW search for pages with
2175 `fetchmail' in their titles.
2178 Eric S. Raymond <esr@snark.thyrsus.com>. Too many other people to
2179 name here have contributed code and patches.
2180 This program is descended from and replaces
2182 by Carl Harris <ceharris@mal.com>; the internals have become quite different,
2183 but some of its interface design is directly traceable to that
2187 mutt(1), elm(1), mail(1), sendmail(8), popd(8), imapd(8), netrc(5)
2188 .SH APPLICABLE STANDARDS
2191 RFC 821, RFC2821, RFC 1869, RFC 1652, RFC 1870, RFC1983, RFC 1985
2194 RFC 822, RFC2822, RFC 1123, RFC 1892, RFC 1894
2200 RFC 1081, RFC 1225, RFC 1460, RFC 1725, RFC1734, RFC 1939, RFC 1957,
2204 RFC 1460, RFC 1725, RFC 1939
2213 RFC 1730, RFC 1731, RFC 1732, RFC 2060, RFC 2061, RFC 2195, RFC 2177,
projects / ~andy / fetchmail / blob