2 .\" ** The above line should force tbl to be used as a preprocessor **
4 .\" Man page for fetchmail
6 .\" For license terms, see the file COPYING in this directory.
9 fetchmail \- fetch mail from a POP, IMAP, or ETRN-capable server
12 \fBfetchmail\fR [\fIoptions\fR] [\fImailserver...\fR]
18 is a mail-retrieval and forwarding utility; it fetches
19 mail from remote mailservers and forwards it to your local (client)
20 machine's delivery system. You can then handle the retrieved mail
21 using normal mail user agents such as \fIelm\fR(1) or \fIMail\fR(1).
22 The \fBfetchmail\fR utility can be run in a daemon mode to repeatedly
23 poll one or more systems at a specified interval.
27 program can gather mail from servers supporting any of the common
28 mail-retrieval protocols: POP2, POP3, IMAP2bis, IMAP4, and IMAPrev1.
29 It can also use the ESMTP ETRN extension. (The RFCs describing all
30 these protocols are listed at the end of this manual page.)
34 is primarily intended to be used over on-demand TCP/IP links (such as
35 SLIP or PPP connections), it may also be useful as a message transfer
36 agent for sites which refuse for security reasons to permit
37 (sender-initiated) SMTP transactions with sendmail.
39 As each message is retrieved \fIfetchmail\fR normally delivers it via SMTP to
40 port 25 on the machine it is running on (localhost), just as though it
41 were being passed in over a normal TCP/IP link. The mail will then be
42 delivered locally via your system's MDA (Mail Delivery Agent, usually
43 \fIsendmail\fR(8) but your system may use a different one such
44 as \fIsmail\fR, \fImmdf\fR, \fIexim\fR, or \fIqmail\fR). All the
45 delivery-control mechanisms (such as \fI.forward\fR files) normally
46 available through your system MDA and local delivery agents will
51 is available, it will assist you in setting up and editing a
52 fetchmailrc configuration. It runs under X and requires that the
53 language Python and the Tk toolkit be present on your system. If
54 you are first setting up fetchmail for single-user mode, it is
55 recommended that you use Novice mode. Expert mode provides
56 complete control of fetchmail configuration, including the
57 multidrop features. In either case, the `Autoprobe' button
58 will tell you the most capable protocol a given mailserver
59 supports, and warn you of potential problems with that server.
64 is controlled by command-line options and a run control file,
65 .IR ~/.fetchmailrc\fR ,
66 the syntax of which we describe in a later section (this file is what
67 the \fIfetchmailconf\fR program edits). Command-line options override
71 Each server name that you specify following the options on the
72 command line will be queried. If you don't specify any servers
73 on the command line, each `poll' entry in your
77 To facilitate the use of
79 in scripts and pipelines, it returns an appropriate exit code upon
80 termination -- see EXIT CODES below.
82 The following options modify the behavior of \fIfetchmail\fR. It is
83 seldom necessary to specify any of these once you have a
84 working \fI.fetchmailrc\fR file set up.
86 Almost all options have a corresponding keyword which can be used to
91 Some special options are not covered here, but are documented instead
92 in sections on AUTHENTICATION and DAEMON MODE which follow.
96 Displays the version information for your copy of
98 No mail fetch is performed.
99 Instead, for each server specified, all the option information
100 that would be computed if
102 were connecting to that server is displayed. Any non-printables in
103 passwords or other string names are shown as backslashed C-like
104 escape sequences. This option is useful for verifying that your
105 options are set the way you want them.
108 Return a status code to indicate whether there is mail waiting,
109 without actually fetching or deleting mail (see EXIT CODES below).
110 This option turns off daemon mode (in which it would be useless). It
111 doesn't play well with queries to multiple sites, and doesn't work
112 with ETRN. It will return a false positive if you leave read but
113 undeleted mail in your server mailbox and your fetch protocol can't
114 tell kept messages from new ones. This means it will work with IMAP,
115 not work with POP2, and may occasionally flake out under POP3.
118 Silent mode. Suppresses all progress/status messages that are
119 normally echoed to standard error during a fetch (but does not
120 suppress actual error messages). The --verbose option overrides this.
123 Verbose mode. All control messages passed between
125 and the mailserver are echoed to stderr. Overrides --silent.
126 Doubling this option (-v -v) causes extra diagnostic information
132 Retrieve both old (seen) and new messages from the mailserver. The
133 default is to fetch only messages the server has not marked seen.
134 Under POP3, this option also forces the use of RETR rather than TOP.
135 Note that POP2 retrieval behaves as though --all is always on (see
136 RETRIEVAL FAILURE MODES below) and this option does not work with ETRN.
140 Keep retrieved messages on the remote mailserver. Normally, messages
141 are deleted from the folder on the mailserver after they have been retrieved.
144 option causes retrieved messages to remain in your folder on the
145 mailserver. This option does not work with ETRN.
149 Delete retrieved messages from the remote mailserver. This
150 option forces retrieved mail to be deleted. It may be useful if
151 you have specified a default of \fBkeep\fR in your
152 \&\fI.fetchmailrc\fR. This option is forced on with ETRN.
155 POP3/IMAP only. Delete old (previously retrieved) messages from the mailserver
156 before retrieving new messages. This option does not work with ETRN.
157 Warning: if your local MTA hangs and fetchmail is aborted, the next
158 time you run fetchmail, it will delete mail that was never delivered to you.
159 What you probably want is the default setting: if you don't specify `-k', then
160 fetchmail will automatically delete messages after successful delivery.
161 .SS Protocol and Query Options
163 .B \-p, \--protocol <proto>
164 (Keyword: proto[col])
165 Specify the protocol to use when communicating with the remote
166 mailserver. If no protocol is specified, the default is AUTO.
168 may be one of the following:
171 Tries IMAP, POP3, and POP2 (skipping any of these for which support
172 has not been compiled in).
174 Post Office Protocol 2
176 Post Office Protocol 3
178 Use POP3 with MD5 authentication.
180 Use POP3 with RPOP authentication.
182 Use POP3 with Kerberos V4 preauthentication on port 1109.
184 Use POP3 with Demon Internet's SDPS extensions.
186 IMAP2bis, IMAP4, or IMAP4rev1 (\fIfetchmail\fR autodetects their capabilities).
188 IMAP4, or IMAP4rev1 (\fIfetchmail\fR autodetects their capabilities)
189 with RFC 1731 Kerberos v4 preauthentication.
191 IMAP4, or IMAP4rev1 (\fIfetchmail\fR autodetects their capabilities)
192 with RFC 1731 GSSAPI preauthentication.
194 IMAP4, or IMAP4rev1 (\fIfetchmail\fR autodetects their capabilities)
195 with RFC 2195 CRAM-MD5 authentication.
197 IMAP4, or IMAP4rev1 (\fIfetchmail\fR autodetects their capabilities)
198 with plain LOGIN authentication only, even if the server supports
201 Use the ESMTP ETRN option.
204 All these alternatives work in basically the same way (communicating
205 with standard server daemons to fetch mail already delivered to a
206 mailbox on the server) except ETRN. The ETRN mode allows you to ask a
207 compliant ESMTP server (such as BSD sendmail at release 8.8.0 or
208 higher) to immediately open a sender-SMTP connection to your
209 client machine and begin forwarding any items addressed to your client
210 machine in the server's queue of undelivered mail.
214 Force UIDL use (effective only with POP3). Force client-side tracking
215 of `newness' of messages (UIDL stands for ``unique ID listing'' and is
216 described in RFC1725). Use with `keep' to use a mailbox as a baby
217 news drop for a group of users.
219 .B \-P, --port <portnumber>
221 The port option permits you to specify a TCP/IP port to connect on.
222 This option will seldom be necessary as all the supported protocols have
223 well-established default port numbers.
225 .B \--principal <principal>
227 The principal option permits you to specify a service principal for
228 mutual authentication. This is applicable to POP3 or IMAP with Kerberos
231 .B \-t, --timeout <seconds>
233 The timeout option allows you to set a server-nonresponse
234 timeout in seconds. If a mailserver does not send a greeting message
235 or respond to commands for the given number of seconds,
236 \fIfetchmail\fR will hang up on it. Without such a timeout
237 \fIfetchmail\fR might hang up indefinitely trying to fetch mail from a
238 down host. This would be particularly annoying for a \fIfetchmail\fR
239 running in background. There is a default timeout which fetchmail -V
240 will report. If a given connection receives too many timeouts in
241 succession, fetchmail will consider it wedged and stop retrying,
242 the calkling user will be notified by email if this happens.
244 .B \--plugin <command>
245 (Keyword: plugin) The plugin option allows you to use an external
246 program to establish the TCP connection. This is useful if you want
247 to use socks, SSL, ssh, or need some special firewalling setup. The
248 program will be looked up in $PATH and can optionally be passed the
249 hostname and port as arguments using "%h" and "%p" respectively (note
250 that the interpolation logic is rather promitive, and these token must
251 be bounded by whitespace or beginning of string or end of string).
252 Fetchmail will write to the plugin's stdin and read from the plugin's
255 .B \--plugout <command>
257 Identical to the plugin option above, but this one is used for the SMTP
258 connections (which will probably not need it, so it has been separated
261 .B \-r <name>, --folder <name>
263 Causes a specified non-default mail folder on the mailserver (or
264 comma-separated list of folders) to be retrieved. The syntax of the
265 folder name is server-dependent. This option is not available under
270 Causes the connection to the mail server to be encrypted via SSL. Connect
271 to the server using the specified base protocol over a connection secured
272 by SSL. SSL support must be present at the server. If no port is
273 specified, the connection is attempted to the well known port of the SSL
274 version of the base protocol. This is generally a different port than the
275 port used by the base protocol. For imap, this is port 143 for the clear
276 protocol and port 993 for the SSL secured protocol.
280 Specifies the file name of the client side public SSL certificate. Some
281 SSL encrypted servers may require client side keys and certificates for
282 authentication. In most cases, this is optional. This specifies
283 the location of the public key certificate to be presented to the server
284 at the time the SSL session is established. It is not required (but may
285 be provided) if the server does not require it. Some servers may
286 require it, some servers may request it but not require it, and some
287 servers may not request it at all. It may be the same file
288 as the private key (combined key and certificate file) but this is not
293 Specifies the file name of the client side private SSL key. Some SSL
294 encrypted servers may require client side keys and certificates for
295 authentication. In most cases, this is optional. This specifies
296 the location of the private key used to sign transactions with the server
297 at the time the SSL session is established. It is not required (but may
298 be provided) if the server does not require it. Some servers may
299 require it, some servers may request it but not require it, and some
300 servers may not request it at all. It may be the same file
301 as the public key (combined key and certificate file) but this is not
302 recommended. If a password is required to unlock the key, it will be
303 prompted for at the time just prior to establishing the session to the
304 server. This can cause some complications in daemon mode.
305 .SS Delivery Control Options
307 .B \-S <hosts>, --smtphost <hosts>
308 (Keyword: smtp[host])
309 Specify a hunt list of hosts to forward mail to (one or more
310 hostnames, comma-separated). In ETRN mode, set the host that the
311 mailserver is asked to ship mail to. Hosts are tried in list order;
312 the first one that is up becomes the forwarding or ETRN target for the
313 current run. Normally, `localhost' is added to the end of the list as
314 an invisible default. However, when using ETRN mode or Kerberos
315 preauthentication, the FQDN of the machine running fetchmail is added to
316 the end of the list as an invisible default. Each hostname may have a
317 port number following the host name. The port number is separated from
318 the host name by a slash; the default port is 25 (or ``smtp'' under IPv6).
319 If you specify an absolute pathname (beginning with a /), it will be
320 interpreted as the name of a UNIX socket accepting LMTP connections
321 (such as is supported by the Cyrus IMAP daemon) Example:
323 --smtphost server1,server2/2525,server3,/var/imap/socket/lmtp
326 .B \-D <domain>, --smtpaddress <domain>
327 (Keyword: smtpaddress)
328 Specify the domain to be put in RCPT TO lines shipped to SMTP. The
329 name of the SMTP server (as specified by --smtphost, or defaulted to
330 "localhost") is used when this is not specified.
332 .B --smtpname <user@domain>
334 Specify the domain and user to be put in RCPT TO lines shipped to SMTP.
335 The default user is the current local user.
337 .B \-Z <nnn>, --antispam <nnn[, nnn]...>
339 Specifies the list of numeric SMTP errors that are to be interpreted
340 as a spam-block response from the listener. A value of -1 disables
341 this option. For the command-line option, the list values should
344 .B \-m <command>, \--mda <command>
346 You can force mail to be passed to an MDA directly (rather than
347 forwarded to port 25) with the -mda or -m option. Be aware that this
348 disables some valuable resource-exhaustion checks and error handling
349 provided by SMTP listeners; it's not a good idea unless running an
350 SMTP listener is impossible. If \fIfetchmail\fR is running as root,
351 it sets its userid to that of the target user while delivering mail
352 through an MDA. Some possible MDAs are "/usr/sbin/sendmail -oem -f %F
353 %T", "/usr/bin/deliver" and "/usr/bin/procmail -d %T" (but the latter
354 is usually redundant as it's what SMTP listeners usually forward
355 to). Local delivery addresses will be inserted into the MDA command
356 wherever you place a %T; the mail message's From address will be
357 inserted where you place an %F. Do \fInot\fR use an MDA invocation
358 like "sendmail -oem -t" that dispatches on the contents of To/Cc/Bcc,
359 it will create mail loops and bring the just wrath of many postmasters
364 Cause delivery via LMTP (Local Mail Transfer Protocol). A service
365 port \fImust\fR be explicitly specified (with a slash suffix) on each
366 host in the smtphost hunt list) if this option is selected; the
367 default port 25 will (in accordance with RFC 2033) not be accepted.
369 .B \--bsmtp <filename>
371 Append fetched mail to a BSMTP file. This simply contains the SMTP
372 commands that would normally be generated by fetchmail when passing
373 mail to an SMTP listener daemon. An argument of `-' causes the mail
374 to be written to standard output. Note that fetchmail's
375 reconstruction of MAIL FROM and RCPT TO lines is not guaranteed
376 correct; the caveats discussed under THE USE AND ABUSE OF MULTIDROP
377 MAILBOXES below apply.
378 .SS Resource Limit Control Options
380 .B \-l <maxbytes>, --limit <maxbytes>
382 Takes a maximum octet size argument. Messages larger than this size
383 will not be fetched and will be left on the server (in foreground
384 sessions, the progress messages will note that they are "oversized").
385 If the fetch protocol permits (in particular, under IMAP or POP3
386 without the fetchall option) the message will not be marked seen An
387 explicit --limit of 0 overrides any limits set in your run control
388 file. This option is intended for those needing to strictly control
389 fetch time due to expensive and variable phone rates. In daemon mode,
390 oversize notifications are mailed to the calling user (see the
391 --warnings option). This option does not work with ETRN.
393 .B \-w <interval>, --warnings <interval>
395 Takes an interval in seconds. When you call
397 with a `limit' option in daemon mode, this controls the interval at
398 which warnings about oversized messages are mailed to the calling user
399 (or the user specified by the `postmaster' option). One such
400 notification is always mailed at the end of the the first poll that
401 the oversized message is detected. Thereafter, renotification is
402 suppressed until after the warning interval elapses (it will take
403 place at the end of the first following poll).
405 .B -b <count>, --batchlimit <count>
406 (Keyword: batchlimit)
407 Specify the maximum number of messages that will be shipped to an SMTP
408 listener before the connection is deliberately torn down and rebuilt
409 (defaults to 0, meaning no limit). An explicit --batchlimit of 0
410 overrides any limits set in your run control file. While
411 \fBsendmail\fR(8) normally initiates delivery of a message immediately
412 after receiving the message terminator, some SMTP listeners are not so
413 prompt. MTAs like \fIqmail\fR(8) and \fIsmail\fR(8) may wait till the
414 delivery socket is shut down to deliver. This may produce annoying
417 is processing very large batches. Setting the batch limit to some
418 nonzero size will prevent these delays.
419 This option does not work with ETRN.
421 .B -B <number>, --fetchlimit <number>
422 (Keyword: fetchlimit)
423 Limit the number of messages accepted from a given server in a single
424 poll. By default there is no limit. An explicit --fetchlimit of 0
425 overrides any limits set in your run control file.
426 This option does not work with ETRN.
428 .B -e <count>, --expunge <count>
430 Arrange for deletions to be made final after a given number of
431 messages. Under POP2 or POP3, fetchmail cannot make deletions final
432 without sending QUIT and ending the session -- with this option on,
433 fetchmail will break a long mail retrieval session into multiple
434 subsessions, sending QUIT after each sub-session. This is a good
435 defense against line drops on POP3 servers that do not do the
436 equivalent of a QUIT on hangup. Under IMAP,
438 normally issues an EXPUNGE command after each deletion in order to
439 force the deletion to be done immediately. This is safest when your
440 connection to the server is flaky and expensive, as it avoids
441 resending duplicate mail after a line hit. However, on large
442 mailboxes the overhead of re-indexing after every message can slam the
443 server pretty hard, so if your connection is reliable it is good to do
444 expunges less frequently. If you specify this option to an integer N,
447 to only issue expunges on every Nth delete. An argument of zero
448 suppresses expunges entirely (so no expunges at all will be done until
449 the end of run). This option does not work with ETRN.
450 .SS Authentication Options
452 .B \-u <name>, --username <name>
453 (Keyword: user[name])
454 Specifies the user identification to be used when logging in to the mailserver.
455 The appropriate user identification is both server and user-dependent.
456 The default is your login name on the client machine that is running
458 See USER AUTHENTICATION below for a complete description.
460 .B \-I <specification>, --interface <specification>
462 Require that a specific interface device be up and have a specific local
463 or remote IP address (or range) before polling. Frequently
465 is used over a transient point-to-point TCP/IP link established directly
466 to a mailserver via SLIP or PPP. That is a relatively secure channel.
467 But when other TCP/IP routes to the mailserver exist (e.g. when the link
468 is connected to an alternate ISP), your username and password may be
469 vulnerable to snooping (especially when daemon mode automatically polls
470 for mail, shipping a clear password over the net at predictable
471 intervals). The --interface option may be used to prevent this. When
472 the specified link is not up or is not connected to a matching IP
473 address, polling will be skipped. The format is:
475 interface/iii.iii.iii.iii/mmm.mmm.mmm.mmm
477 The field before the first slash is the interface name (i.e. sl0, ppp0
478 etc.). The field before the second slash is the acceptable IP address.
479 The field after the second slash is a mask which specifies a range of
480 IP addresses to accept. If no mask is present 255.255.255.255 is
481 assumed (i.e. an exact match). This option is currently only supported
482 under Linux and FreeBSD. Please see the
484 section for below for FreeBSD specific information.
486 .B \-M <interface>, --monitor <interface>
488 Daemon mode can cause transient links which are automatically taken down
489 after a period of inactivity (e.g. PPP links) to remain up
490 indefinitely. This option identifies a system TCP/IP interface to be
491 monitored for activity. After each poll interval, if the link is up but
492 no other activity has occurred on the link, then the poll will be
493 skipped. However, when fetchmail is woken up by a signal, the
494 monitor check is skipped and the poll goes through unconditionally.
495 This option is currently only supported under Linux and FreeBSD.
500 options to work for non root users under FreeBSD, the fetchmail binary
501 must be installed SGID kmem. This would be a security hole, but
502 fetchmail runs with the effective GID set to that of the kmem group
504 when interface data is being collected.
507 (Keyword: preauth[enticate])
508 This option permits you to specify a preauthentication type (see USER
509 AUTHENTICATION below for details). The possible values are
510 \&`\fBpassword\fR', `\fBkerberos_v5\fR' and `\fBkerberos\fR' (or, for
511 excruciating exactness, `\fBkerberos_v4\fR'), and \fBssh\fR. Use
512 \fBssh\fR to suppress fetchmail's normal inquiry for a password when
513 you are using an end-to-end secure connection such as an ssh tunnel.
514 Other values of this option are provided primarily for developers;
515 choosing KPOP protocol automatically selects Kerberos
516 preauthentication, and all other alternatives use password
517 authentication (though APOP uses a generated one-time key as the
518 password and IMAP-K4 uses RFC1731 Kerberos v4 authentication). This
519 option does not work with ETRN.
520 .SS Miscellaneous Options
522 .B \-f <pathname>, --fetchmailrc <pathname>
523 Specify a non-default name for the
525 run control file. The pathname argument must be either "-" (a single
526 dash, meaning to read the configuration from standard input) or a
527 filename. Unless the --version option is also on, a named file
528 argument must have permissions no more open than 0600 (u=rw,g=,o=) or
531 .B \-i <pathname>, --idfile <pathname>
533 Specify an alternate name for the .fetchids file used to save POP3
537 (Keyword: no rewrite)
540 edits RFC-822 address headers (To, From, Cc, Bcc, and Reply-To) in
541 fetched mail so that any mail IDs local to the server are expanded to
542 full addresses (@ and the mailserver hostname are appended). This enables
543 replies on the client to get addressed correctly (otherwise your
544 mailer might think they should be addressed to local users on the
545 client machine!). This option disables the rewrite. (This option is
546 provided to pacify people who are paranoid about having an MTA edit
547 mail headers and want to know they can prevent it, but it is generally
548 not a good idea to actually turn off rewrite.)
549 When using ETRN, the rewrite option is ineffective.
551 .B -E <line>, --envelope <line>
553 This option changes the header
555 assumes will carry a copy of the mail's envelope address. Normally
556 this is `X-Envelope-To' but as this header is not standard, practice
557 varies. See the discussion of multidrop address handling below. As a
558 special case, `envelope "Received"' enables parsing of sendmail-style
559 Received lines. This is the default, and it should not be necessary
560 unless you have globally disabled Received parsing with `no envelope'
561 in the \fI.fetchmailrc\fR file.
563 .B -Q <prefix>, --qvirtual <prefix>
565 The string prefix assigned to this option will be removed from the user
566 name found in the header specified with the \fIenvelope\fR option
567 (\fIbefore\fR doing multidrop name mapping or localdomain checking,
568 if either is applicable). This option is useful if you are using
570 to collect the mail for an entire domain and your ISP (or your mail
571 redirection provider) is using qmail.
572 One of the basic features of qmail is the
576 message header. Whenever qmail delivers a message to a local mailbox
577 it puts the username and hostname of the envelope recipient on this
578 line. The major reason for this is to prevent mail loops. To set up
579 qmail to batch mail for a disconnected site the ISP-mailhost will have
580 normally put that site in its `Virtualhosts' control file so it will
581 add a prefix to all mail addresses for this site. This results in mail
582 sent to 'username@userhost.userdom.dom.com' having a
583 \&`Delivered-To:' line of the form:
585 Delivered-To: mbox-userstr-username@userhost.userdom.dom.com
587 The ISP can make the 'mbox-userstr-' prefix anything they choose
588 but a string matching the user host name is likely.
589 By using the option `envelope Delivered-To:' you can make fetchmail reliably
590 identify the original envelope recipient, but you have to strip the
591 `mbox-userstr-' prefix to deliver to the correct user.
592 This is what this option is for.
597 file, interpret any command-line options specified, and dump a
598 configuration report to standard output. The configuration report is
599 a data structure assignment in the language Python. This option
600 is meant to be used with an interactive
606 .SH USER AUTHENTICATION AND ENCRYPTION
607 Every mode except ETRN requires authentication of the client.
608 Normal user authentication in
610 is very much like the authentication mechanism of
612 The correct user-id and password depend upon the underlying security
613 system at the mailserver.
615 If the mailserver is a Unix machine on which you have an ordinary user
616 account, your regular login name and password are used with
618 If you use the same login name on both the server and the client machines,
619 you needn't worry about specifying a user-id with the
622 the default behavior is to use your login name on the client machine as the
623 user-id on the server machine. If you use a different login name
624 on the server machine, specify that login name with the
626 option. e.g. if your login name is 'jsmith' on a machine named 'mailgrunt',
631 fetchmail -u jsmith mailgrunt
633 The default behavior of
635 is to prompt you for your mailserver password before the connection is
636 established. This is the safest way to use
638 and ensures that your password will not be compromised. You may also specify
639 your password in your
641 file. This is convenient when using
643 in daemon mode or with scripts.
645 If you do not specify a password, and
647 cannot extract one from your
649 file, it will look for a
651 file in your home directory before requesting one interactively; if an
652 entry matching the mailserver is found in that file, the password will
653 be used. Fetchmail first looks for a match on poll name; if it finds none,
654 it checks for a match on via name. See the
656 man page for details of the syntax of the
658 file. (This feature may allow you to avoid duplicating password
659 information in more than one file.)
661 On mailservers that do not provide ordinary user accounts, your user-id and
662 password are usually assigned by the server administrator when you apply for
663 a mailbox on the server. Contact your server administrator if you don't know
664 the correct user-id and password for your mailbox account.
666 Early versions of POP3 (RFC1081, RFC1225) supported a crude form of
667 independent authentication using the
669 file on the mailserver side. Under this RPOP variant, a fixed
670 per-user ID equivalent to a password was sent in clear over a link to
671 a reserved port, with the command RPOP rather than PASS to alert the
672 server that it should do special checking. RPOP is supported
675 (you can specify `protocol RPOP' to have the program send `RPOP'
676 rather than `PASS') but its use is strongly discouraged. This
677 facility was vulnerable to spoofing and was withdrawn in RFC1460.
679 RFC1460 introduced APOP authentication. In this variant of POP3,
680 you register an APOP password on your server host (the program
681 to do this with on the server is probably called \fIpopauth\fR(8)). You
682 put the same password in your
686 logs in, it sends a cryptographically secure hash of your password and
687 the server greeting time to the server, which can verify it by
688 checking its authorization database.
690 If your \fIfetchmail\fR was built with Kerberos support and you specify
691 Kerberos preauthentication (either with --auth or the \fI.fetchmailrc\fR
692 option \fBauthenticate kerberos_v4\fR) it will try to get a Kerberos
693 ticket from the mailserver at the start of each query. Note: if
694 either the pollnane or via name is `hesiod', fetchmail will try to use
695 Hesiod to look up the mailserver.
697 If you use IMAP-K4, \fIfetchmail\fR will expect the IMAP server to have
698 RFC1731-conformant AUTHENTICATE KERBEROS_V4 capability, and will use it.
700 If you use IMAP-GSS, \fIfetchmail\fR will expect the IMAP server to have
701 RFC1731-conformant AUTHENTICATE GSSAPI capability, and will use it.
702 Currently this has only been tested over Kerberos V, so you're expected
703 to already have a ticket-granting ticket. You may pass a username different
704 from your principal name using the standard \fB--user\fR command or by
705 the \fI.fetchmailrc\fR option \fBuser\fR.
707 If your IMAP daemon returns the PREAUTH response in its greeting line,
708 fetchmail will notice this and skip the normal authentication step.
709 This could be useful, e.g. if you start imapd explicitly using ssh.
710 In this case you can declare the preauthentication value `ssh' on that
711 site entry to stop \fI.fetchmail\fR from asking you for a password
714 If you are using POP3, and the server issues a one-time-password
715 challenge conforming to RFC1938, \fIfetchmail\fR will use your
716 password as a pass phrase to generate the required response. This
717 avoids sending secrets over the net unencrypted.
719 Compuserve's RPA authentication (similar to APOP) is supported. If you
720 compile in the support, \fIfetchmail\fR will try to perform an RPA pass-phrase
721 authentication instead of sending over the password en clair if it
722 detects "@compuserve.com" in the hostname.
724 Microsoft's NTLM authentication (used by Microsoft Exchange) is
725 supported. If you compile in the support, \fIfetchmail\fR will try to
726 perform an NTLM authentication (instead of sending over the
727 password en clair) whenever the server returns AUTH=NTLM in its
728 capability response. Note: if you specify a user option value
729 that looks like `user@domain', the part to the left of the @ will
730 be passed as the username and the part to the right as the NTLM domain.
732 If you are using IPsec, the -T (--netsec) option can be used to pass
733 an IP security request to be used when outgoing IP connections are
734 initialized. You can also do this using the `netsec' server option
735 in the .fetchmailrc file. In either case, the option value is a
736 string in the format accepted by the net_security_strtorequest()
737 function of the inet6_apps library.
739 You can access SSL encrypted services by specifying the --ssl option.
740 You can also do this using the "ssl" server option in the .fetchmailrc
741 file. With SSL encryption enabled, queries are initiated over a connection
742 after negotiating an SSL session. Some services, such as POP3 and IMAP,
743 have different well known ports defined for the SSL encrypted services.
744 The encrypted ports will be selected automatically when SSL is enabled and
745 no explicit port is specified.
747 When connecting to an SSL encrypted server, the server presents a certificate
748 to the client for validation. The certificate is checked to verify that
749 the common name in the certificate matches the name of the server being
750 contacted and that the effective and expiration dates in the certificate
751 indicate that it is currently valid. If any of these checks fail, a warning
752 message is printed, but the connection continues. The server certificate
753 does not need to be signed by any specific Certifying Authority and may
754 be a "self-signed" certificate.
756 Some SSL encrypted servers may request a client side certificate. A client
757 side public SSL certificate and private SSL key may be specified. If
758 requested by the server, the client certificate is sent to the server for
759 validation. Some servers may require a valid client certificate and may
760 refuse connections if a certificate is not provided or if the certificate
761 is not valid. Some servers may require client side certificates be signed
762 by a recognized Certifying Authority. The format for the key files and
763 the certificate files is that required by the underlying SSL libraries
764 (OpenSSL in the general case).
768 .B --daemon <interval>
773 in daemon mode. You must specify a numeric argument which is a
774 polling interval in seconds.
778 puts itself in background and runs forever, querying each specified
779 host and then sleeping for the given polling interval.
785 will, therefore, poll all the hosts described in your
787 file (except those explicitly excluded with the `skip' verb) once
788 every fifteen minutes.
790 It is possible to set a polling interval
793 file by saying `set daemon <interval>', where <interval> is an
794 integer number of seconds. If you do this, fetchmail will always
795 start in daemon mode unless you override it with the command-line
796 option --daemon 0 or -d0.
798 Only one daemon process is permitted per user; in daemon mode,
800 makes a per-user lockfile to guarantee this.
802 Normally, calling fetchmail with a daemon in the background sends a
803 wakeup signal to the daemon, forcing it to poll mailservers
804 immediately. (The wakeup signal is SIGHUP if fetchmail is running as
805 root, SIGUSR1 otherwise.) The wakeup action also clears any `wedged'
806 flags indicating that connections have wedged due to failed
807 authentication or multiple timeouts.
811 will kill a running daemon process instead of waking it up (if there
814 notifies you). If the --quit option is the only command-line option,
815 that's all there is to it.
817 The quit option may also be mixed with other command-line options; its
818 effect is to kill any running daemon before doing what the other
819 options specify in combination with the rc file.
824 .B --logfile <filename>
825 option (keyword: set logfile) allows you to redirect status messages
826 emitted while detached into a specified logfile (follow the
827 option with the logfile name). The logfile is opened for append, so
828 previous messages aren't deleted. This is primarily useful for
829 debugging configurations.
833 option (keyword: set syslog) allows you to redirect status and error
834 messages emitted to the
836 system daemon if available.
837 Messages are logged with an id of \fBfetchmail\fR, the facility \fBLOG_MAIL\fR,
838 and priorities \fBLOG_ERR\fR, \fBLOG_ALERT\fR or \fBLOG_INFO\fR.
839 This option is intended for logging status and error messages which
840 indicate the status of the daemon and the results while fetching mail
842 Error messages for command line options and parsing the \fI.fetchmailrc\fR
843 file are still written to stderr, or to the specified log file.
846 option turns off use of
848 assuming it's turned on in the
858 or --nodetach option suppresses backgrounding and detachment of the
859 daemon process from its control terminal. This is primarily useful
860 for debugging. Note that this also causes the logfile option to be
861 ignored (though perhaps it shouldn't).
863 Note that while running in daemon mode polling a POP2 or IMAP2bis server,
864 transient errors (such as DNS failures or sendmail delivery refusals)
865 may force the fetchall option on for the duration of the next polling
866 cycle. This is a robustness feature. It means that if a message is
867 fetched (and thus marked seen by the mailserver) but not delivered
868 locally due to some transient error, it will be re-fetched during the
869 next poll cycle. (The IMAP logic doesn't delete messages until
870 they're delivered, so this problem does not arise.)
872 If you touch or change the
874 file while fetchmail is running in daemon mode, this will be detected
875 at the beginning of the next poll cycle. When a changed
877 is detected, fetchmail rereads it and restarts from scratch (using
878 exec(2); no state information is retained in the new instance). Note also
879 that if you break the
881 file's syntax, the new instance will softly and silently vanish away
884 .SH ADMINISTRATIVE OPTIONS
887 .B --postmaster <name>
888 option (keyword: set postmaster) specifies the last-resort username to
889 which multidrop mail is to be forwarded if no matching local recipient
890 can be found. Normally this is just the user who invoked fetchmail.
891 If the invoking user is root, then the default of this option is
892 the user `postmaster'.
896 option suppresses the normal action of bouncing errors back to the
897 sender in an RFC1894-conformant error message. If nobounce is on, the
898 message will go to the postmaster instead.
902 option (keyword: set invisible) tries to make fetchmail invisible.
903 Normally, fetchmail behaves like any other MTA would -- it generates a
904 Received header into each message describing its place in the chain of
905 transmission, and tells the MTA it forwards to that the mail came from
906 the machine fetchmail itself is running on. If the invisible option
907 is on, the Received header is suppressed and fetchmail tries to spoof
908 the MTA it forwards to into thinking it came directly from the
913 option (keyword: set showdots) forces fetchmail to show progress dots
914 even if the current tty is not stdout (for example logfiles).
915 Starting with fetchmail version 5.3.0,
916 progress dots are only shown on stdout by default.
918 .SH RETRIEVAL FAILURE MODES
919 The protocols \fIfetchmail\fR uses to talk to mailservers are next to
920 bulletproof. In normal operation forwarding to port 25, no message is
921 ever deleted (or even marked for deletion) on the host until the SMTP
922 listener on the client has acknowledged to \fIfetchmail\fR that the
923 message has been accepted for delivery or rejected due to a spam
924 block. When forwarding to an MDA, however, there is more possibility
925 of error (because there's no way for fetchmail to get a reliable
926 positive acknowledgement from the MDA).
928 The normal mode of \fIfetchmail\fR is to try to download only `new'
929 messages, leaving untouched (and undeleted) messages you have already
930 read directly on the server (or fetched with a previous \fIfetchmail
931 --keep\fR). But you may find that messages you've already read on the
932 server are being fetched (and deleted) even when you don't specify
933 --all. There are several reasons this can happen.
935 One could be that you're using POP2. The POP2 protocol includes no
936 representation of `new' or `old' state in messages, so \fIfetchmail\fR
937 must treat all messages as new all the time. But POP2 is obsolete, so
940 Under POP3, blame RFC1725. That version of the POP3 protocol
941 specification removed the LAST command, and some POP servers follow it
942 (you can verify this by invoking \fIfetchmail -v\fR to the mailserver
943 and watching the response to LAST early in the query). The
944 \fIfetchmail\fR code tries to compensate by using POP3's UID feature,
945 storing the identifiers of messages seen in each session until the
946 next session, in the \fI.fetchids\fR file. But this doesn't track
947 messages seen with other clients, or read directly with a mailer on
948 the host but not deleted afterward. A better solution would be to
951 Another potential POP3 problem might be servers that insert messages
952 in the middle of mailboxes (some VMS implementations of mail are
953 rumored to do this). The \fIfetchmail\fR code assumes that new
954 messages are appended to the end of the mailbox; when this is not true
955 it may treat some old messages as new and vice versa. The only
956 real fix for this problem is to switch to IMAP.
958 Yet another POP3 problem is that if they can't make tempfiles in the
959 user's home directory, some POP3 servers will hand back an
960 undocumented response that causes fetchmail to spuriously report "No
963 The IMAP code uses the presence or absence of the server flag \eSeen
964 to decide whether or not a message is new. Under Unix, it counts on
965 your IMAP server to notice the BSD-style Status flags set by mail user
966 agents and set the \eSeen flag from them when appropriate. All Unix
967 IMAP servers we know of do this, though it's not specified by the IMAP
968 RFCs. If you ever trip over a server that doesn't, the symptom will
969 be that messages you have already read on your host will look new to
970 the server. In this (unlikely) case, only messages you fetched with
971 \fIfetchmail --keep\fR will be both undeleted and marked old.
973 In ETRN mode, \fIfetchmail\fR does not actually retrieve messages;
974 instead, it asks the server's SMTP listener to start a queue flush
975 to the client via SMTP. Therefore it sends only undelivered messages.
978 Many SMTP listeners allow administrators to set up `spam filters' that
979 block unsolicited email from specified domains. A MAIL FROM or DATA line that
980 triggers this feature will elicit an SMTP response which
981 (unfortunately) varies according to the listener.
985 return an error code of 571. This return value
986 is blessed by RFC1893 as "Delivery not authorized, message refused".
988 According to current drafts of the replacement for RFC821, the correct
989 thing to return in this situation is 550 "Requested action not taken:
990 mailbox unavailable" (the draft adds "[E.g., mailbox not found, no
991 access, or command rejected for policy reasons].").
995 MTA returns 501 "Syntax error in parameters or arguments", but will
1000 MTA runs 554 as an antispam response.
1004 code recognizes and discards the message on any of a list of responses
1005 that defaults to [571, 550, 501, 554] but can be set with the `antispam'
1006 option. This is one of the
1008 three circumstance under which fetchmail ever discards mail (the others
1009 are the 552 and 553 errors described below, and the suppression of
1010 multidropped messages with a message-ID already seen).
1014 is fetching from an IMAP server, the antispam response will be detected and
1015 the message rejected immediately after the headers have been fetched,
1016 without reading the message body. Thus, you won't pay for downloading
1017 spam message bodies.
1019 Mail that is spam-blocked triggers an RFC1892 bounce message informing
1020 the originator that we do not accept mail from it.
1022 .SH SMTP/ESMTP ERROR HANDLING
1023 Besides the spam-blocking described above,fetchmail takes special
1024 actions on the following SMTP/ESMTP error responses
1026 452 (insufficient system storage)
1027 Leave the message in the server mailbox for later retrieval.
1029 552 (message exceeds fixed maximum message size)
1030 Delete the message from the server. Send bounce-mail to the originator.
1032 553 (invalid sending domain)
1033 Delete the message from the server. Send bounce-mail to the originator.
1035 Other errors trigger bounce mail back to the originator.
1037 .SH THE RUN CONTROL FILE
1038 The preferred way to set up fetchmail is to write a
1039 \&\fI.fetchmailrc\fR file in your home directory (you may do this
1040 directly, with a text editor, or indirectly via \fIfetchmailconf\fR).
1041 When there is a conflict between the command-line arguments and the
1042 arguments in this file, the command-line arguments take precedence.
1044 To protect the security of your passwords, when --version is not on
1045 your \fI~/.fetchmailrc\fR may not have more than 0600 (u=rw,g=,o=) permissions;
1047 will complain and exit otherwise.
1049 You may read the \fI.fetchmailrc\fR file as a list of commands to
1052 is called with no arguments.
1053 .SS Run Control Syntax
1055 Comments begin with a '#' and extend through the end of the line.
1056 Otherwise the file consists of a series of server entries or global
1057 option statements in a free-format, token-oriented syntax.
1059 There are four kinds of tokens: grammar keywords, numbers
1060 (i.e. decimal digit sequences), unquoted strings, and quoted strings.
1061 A quoted string is bounded by double quotes and may contain
1062 whitespace (and quoted digits are treated as a string). An unquoted
1063 string is any whitespace-delimited token that is neither numeric, string
1064 quoted nor contains the special characters `,', `;', `:', or `='.
1066 Any amount of whitespace separates tokens in server entries, but is
1067 otherwise ignored. You may use standard C-style escapes (\en, \et,
1068 \eb, octal, and hex) to embed non-printable characters or string
1069 delimiters in strings.
1071 Each server entry consists of one of the keywords `poll' or `skip',
1072 followed by a server name, followed by server options, followed by any
1073 number of user descriptions. Note: the most common cause of syntax
1074 errors is mixing up user and server options.
1076 For backward compatibility, the word `server' is a synonym for `poll'.
1078 You can use the noise keywords `and', `with',
1079 \&`has', `wants', and `options' anywhere in an entry to make
1080 it resemble English. They're ignored, but but can make entries much
1081 easier to read at a glance. The punctuation characters ':', ';' and
1082 \&',' are also ignored.
1085 The `poll' verb tells fetchmail to query this host when it is run with
1086 no arguments. The `skip' verb tells
1088 not to poll this host unless it is explicitly named on the command
1089 line. (The `skip' verb allows you to experiment with test entries
1090 safely, or easily disable entries for hosts that are temporarily down.)
1092 .SS Keyword/Option Summary
1093 Here are the legal options. Keyword suffixes enclosed in
1094 square brackets are optional. Those corresponding to command-line
1095 options are followed by `-' and the appropriate option letter.
1097 Here are the legal global options:
1101 Keyword Opt Function
1104 Set a background poll interval in seconds
1106 set postmaster \& T{
1107 Give the name of the last-resort mail recipient
1109 set no bouncemail \& T{
1110 Direct error mail to postmaster rather than sender
1112 set no spambounce \& T{
1116 Name of a file to dump error and status messages to
1119 Name of the file to store UID lists in
1122 Do error logging through syslog(3).
1125 Turn off error logging through syslog(3).
1127 set properties \& T{
1128 String value is ignored by fetchmail (may be used by extension scripts)
1132 Here are the legal server options:
1136 Keyword Opt Function
1139 Specify DNS name of mailserver, overriding poll name
1142 Specify protocol (case insensitive):
1143 POP2, POP3, IMAP, IMAP-K4, IMAP-GSS, APOP, KPOP
1145 local[domains] \& T{
1146 Specify domain(s) to be regarded as local
1149 Specify TCP/IP service port
1151 auth[enticate] -A T{
1152 Set preauthentication type (default `password')
1155 Server inactivity timeout in seconds (default 300)
1158 Specify envelope-address header name
1161 Disable looking for envelope address
1164 Qmail virtual domain prefix to remove from user name
1167 Specify alternate DNS names of mailserver
1170 specify IP interface(s) that must be up for server poll to take place
1173 Specify IP address to monitor for activity
1176 Specify command through which to make server connections.
1179 Specify command through which to make listener connections.
1182 Enable DNS lookup for multidrop (default)
1185 Disable DNS lookup for multidrop
1188 Do comparison by IP address for multidrop
1191 Do comparison by name for multidrop (default)
1194 Force POP3 to use client-side UIDLs
1197 Turn off POP3 use of client-side UIDLs (default)
1200 Only check this site every N poll cycles; N is a numeric argument.
1203 Pass in IPsec security option request.
1206 Set Kerberos principal (only useful with imap-k4)
1210 Here are the legal user options:
1214 Keyword Opt Function
1217 Set remote user name
1218 (local user name if name followed by `here')
1221 Connect local and remote user names
1224 Connect local and remote user names
1227 Specify remote account password
1230 Connect to server over the specified base protocol using SSL encryption
1233 Specify file for client side public SSL certificate
1236 Specify file for client side private SSL key
1239 Specify remote folder to query
1242 Specify smtp host(s) to forward to
1245 Specify the domain to be put in RCPT TO lines
1248 Specify the user and domain to be put in RCPT TO lines
1251 Specify what SMTP returns are interpreted as spam-policy blocks
1254 Specify MDA for local delivery
1257 Specify BSMTP batch file to append to
1260 Command to be executed before each connection
1263 Command to be executed after each connection
1266 Don't delete seen messages from server
1269 Flush all seen messages before querying
1272 Fetch all messages whether seen or not
1275 Rewrite destination addresses for reply (default)
1278 Strip carriage returns from ends of lines
1281 Force carriage returns at ends of lines
1284 Force BODY=8BITMIME to ESMTP listener
1287 Strip Status and X-Mozilla-Status lines out of incoming mail
1290 Strip Delivered-To lines out of incoming mail
1293 Convert quoted-printable to 8-bit in MIME messages
1296 Idle waiting for new messages after each poll (IMAP only)
1299 Delete seen messages from server (default)
1302 Don't flush all seen messages before querying (default)
1305 Retrieve only new messages (default)
1308 Don't rewrite headers
1311 Don't strip carriage returns (default)
1314 Don't force carriage returns at EOL (default)
1317 Don't force BODY=8BITMIME to ESMTP listener (default)
1320 Don't drop Status headers (default)
1322 no dropdelivered \& T{
1323 Don't drop Delivered-To headers (default)
1326 Don't convert quoted-printable to 8-bit in MIME messages (default)
1329 Don't idle waiting for new messages after each poll (IMAP only)
1332 Set message size limit
1335 Set message size warning interval
1338 Max # messages to forward in single connect
1341 Max # messages to fetch in single connect
1344 Perform an expunge on every #th message (IMAP and POP3 only)
1347 String value is ignored by fetchmail (may be used by extension scripts)
1351 Remember that all user options must \fIfollow\fR all server options.
1353 In the .fetchmailrc file, the `envelope' string argument may be
1354 preceded by a whitespace-separated number. This number, if specified,
1355 is the number of such headers to skip (that is, an argument of 1
1356 selects the second header of the given type). This is sometime useful
1357 for ignoring bogus Received headers created by an ISP's local delivery
1359 .SS Keywords Not Corresponding To Option Switches
1361 The `folder' and `smtphost' options (unlike their command-line
1362 equivalents) can take a space- or comma-separated list of names
1365 All options correspond to the obvious command-line arguments, except
1366 the following: `via', `interval', `aka', `is', `to', `dns'/`no dns',
1367 `checkalias'/`no checkalias', `password', `preconnect', `postconnect',
1368 `localdomains', `stripcr'/`no stripcr', `forcecr'/`no forcecr',
1369 `pass8bits'/`no pass8bits' `dropstatus/no dropstatus',
1370 `dropdelivered/no dropdelivered', `mimedecode/no mimedecode', `idle/no
1371 idle', and `no envelope'.
1373 The `via' option is for use with ssh, or if you want to have more
1374 than one configuration pointing at the same site. If it is present,
1375 the string argument will be taken as the actual DNS name of the
1376 mailserver host to query.
1377 This will override the argument of poll, which can then simply be a
1378 distinct label for the configuration (e.g. what you would give on the
1379 command line to explicitly query this host).
1380 If the `via' name is `localhost', the poll name will also still be
1381 used as a possible match in multidrop mode; otherwise the `via' name
1382 will be used instead and the poll name will be purely a label.
1384 The `interval' option (which takes a numeric argument) allows you to poll a
1385 server less frequently than the basic poll interval. If you say
1386 \&`interval N' the server this option is attached to will only be
1387 queried every N poll intervals.
1389 The `is' or `to' keywords associate the following local (client)
1390 name(s) (or server-name to client-name mappings separated by =) with
1391 the mailserver user name in the entry. If an is/to list has `*' as
1392 its last name, unrecognized names are simply passed through.
1394 A single local name can be used to support redirecting your mail when
1395 your username on the client machine is different from your name on the
1396 mailserver. When there is only a single local name, mail is forwarded
1397 to that local username regardless of the message's Received, To, Cc,
1398 and Bcc headers. In this case
1400 never does DNS lookups.
1402 When there is more than one local name (or name mapping) the
1403 \fIfetchmail\fR code does look at the Received, To, Cc, and Bcc
1404 headers of retrieved mail (this is `multidrop mode'). It looks for
1405 addresses with hostname parts that match your poll name or your `via',
1406 `aka' or `localdomains' options, and usually also for hostname parts
1407 which DNS tells it are aliases of the mailserver. See the discussion
1408 of `dns', `checkalias', `localdomains', and `aka' for details on how
1409 matching addresses are handled.
1411 If \fIfetchmail\fR cannot match any mailserver usernames or
1412 localdomain addresses, the mail will be bounced.
1413 Normally it will be bounced to the sender, but if `nobounce' is on
1414 it will go to the postmaster (which in turn defaults to being the
1417 The `dns' option (normally on) controls the way addresses from
1418 multidrop mailboxes are checked. On, it enables logic to check each
1419 host address that doesn't match an `aka' or `localdomains' declaration
1420 by looking it up with DNS. When a mailserver username is recognized
1421 attached to a matching hostname part, its local mapping is added to
1422 the list of local recipients.
1424 The `checkalias' option (normally off) extends the lookups performed
1425 by the `dns' keyword in multidrop mode, providing a way to cope with
1426 remote MTAs that identify themselves using their canonical name, while
1427 they're polled using an alias.
1428 When such a server is polled, checks to extract the envelope address
1431 reverts to delivery using the To/Cc/Bcc headers (See below
1432 `Header vs. Envelope addresses').
1433 Specifying this option instructs
1435 to retrieve all the IP addresses associated with both the poll name
1436 and the name used by the remote MTA and to do a comparison of the IP
1437 addresses. This comes in handy in situations where the remote server
1438 undergoes frequent canonical name changes, that would otherwise
1439 require modifications to the rcfile. `checkalias' has no effect if
1440 `no dns' is specified in the rcfile.
1442 The `aka' option is for use with multidrop mailboxes. It allows you
1443 to pre-declare a list of DNS aliases for a server. This is an
1444 optimization hack that allows you to trade space for speed. When
1446 while processing a multidrop mailbox, grovels through message headers
1447 looking for names of the mailserver, pre-declaring common ones can
1448 save it from having to do DNS lookups. Note: the names you give
1449 as arguments to `aka' are matched as suffixes -- if you specify
1450 (say) `aka netaxs.com', this will match not just a hostnamed
1451 netaxs.com, but any hostname that ends with `.netaxs.com'; such as
1452 (say) pop3.netaxs.com and mail.netaxs.com.
1454 The `localdomains' option allows you to declare a list of domains
1455 which fetchmail should consider local. When fetchmail is parsing
1456 address lines in multidrop modes, and a trailing segment of a host
1457 name matches a declared local domain, that address is passed through
1458 to the listener or MDA unaltered (local-name mappings are \fInot\fR
1461 If you are using `localdomains', you may also need to specify \&`no
1462 envelope', which disables \fIfetchmail\fR's normal attempt to deduce
1463 an envelope address from the Received line or X-Envelope-To header or
1464 whatever header has been previously set by `envelope'. If you set `no
1465 envelope' in the defaults entry it is possible to undo that in
1466 individual entries by using `envelope <string>'. As a special case,
1467 \&`envelope "Received"' restores the default parsing of
1470 The \fBpassword\fR option requires a string argument, which is the password
1471 to be used with the entry's server.
1473 The `preconnect' keyword allows you to specify a shell command to be
1474 executed just before each time
1476 establishes a mailserver connection. This may be useful if you are
1477 attempting to set up secure POP connections with the aid of
1479 If the command returns a nonzero status, the poll of that mailserver
1482 Similarly, the `postconnect' keyword similarly allows you to specify a
1483 shell command to be executed just after each time a mailserver
1484 connection is taken down.
1486 The `forcecr' option controls whether lines terminated by LF only are
1487 given CRLF termination before forwarding. Strictly speaking RFC821
1488 requires this, but few MTAs enforce the requirement it so this option
1489 is normally off (only one such MTA, qmail, is in significant use at
1492 The `stripcr' option controls whether carriage returns are stripped
1493 out of retrieved mail before it is forwarded. It is normally not
1494 necessary to set this, because it defaults to `on' (CR stripping
1495 enabled) when there is an MDA declared but `off' (CR stripping
1496 disabled) when forwarding is via SMTP. If `stripcr' and `forcecr' are
1497 both on, `stripcr' will override.
1499 The `pass8bits' option exists to cope with Microsoft mail programs that
1500 stupidly slap a "Content-Transfer-Encoding: 7bit" on everything. With
1501 this option off (the default) and such a header present,
1503 declares BODY=7BIT to an ESMTP-capable listener; this causes problems for
1504 messages actually using 8-bit ISO or KOI-8 character sets, which will
1505 be garbled by having the high bits of all characters stripped. If
1506 \&`pass8bits' is on,
1508 is forced to declare BODY=8BITMIME to any ESMTP-capable listener. If
1509 the listener is 8-bit-clean (as all the major ones now are) the right
1510 thing will probably result.
1512 The `dropstatus' option controls whether nonempty Status and
1513 X-Mozilla-Status lines are retained in fetched mail (the default) or
1514 discarded. Retaining them allows your MUA to see what messages (if
1515 any) were marked seen on the server. On the other hand, it can
1516 confuse some new-mail notifiers, which assume that anything with a
1517 Status line in it has been seen. (Note: the empty Status lines
1518 inserted by some buggy POP servers are unconditionally discarded.)
1520 The `dropdelivered' option controls wether Delivered-To headers will
1521 be kept in fetched mail (the default) or discarded. These headers are
1522 added by Qmail and Postfix mailservers in order to avoid mail loops but
1523 may get in your way if you try to "mirror" a mailserver within the same
1524 domain. Use with caution.
1526 The `mimedecode' option controls whether MIME messages using the
1527 quoted-printable encoding are automatically converted into pure 8-bit
1528 data. If you are delivering mail to an ESMTP-capable, 8-bit-clean
1529 listener (that includes all of the major MTAs like sendmail), then
1530 this will automatically convert quoted-printable message headers and
1531 data into 8-bit data, making it easier to understand when reading
1532 mail. If your e-mail programs know how to deal with MIME messages,
1533 then this option is not needed. The mimedecode option is off by
1534 default, because doing RFC2047 conversion on headers throws away
1535 character-set information and can lead to bad results if the encoding
1536 of the headers differs from the body encoding.
1538 The `idle' option is usable only with IMAP servers supporting the
1539 RFC2177 IDLE command extension. If it is enabled, and fetchmail
1540 detects that IDLE is supported, an IDLE will be issued at the end
1541 of each poll. This will tell the IMAP server to hold the connection
1542 open and notify the client when new mail is available. If you need to
1543 poll a link frequently, IDLE can save bandwidth by eliminating TCP/IP
1544 connects and LOGIN/LOGOUT sequences. On the other hand, an IDLE
1545 connection will eat almost akll of your fetchmail's time, because it
1546 will never drop the connection and allow other pools to occur unless
1547 the server times out the IDLE.
1549 The `properties' option is an extension mechanism. It takes a string
1550 argument, which is ignored by fetchmail itself. The string argument may be
1551 used to store configuration information for scripts which require it.
1552 In particular, the output of `--configdump' option will make properties
1553 associated with a user entry readily available to a Python script.
1555 .SS Miscellaneous Run Control Options
1556 The words `here' and `there' have useful English-like
1557 significance. Normally `user eric is esr' would mean that
1558 mail for the remote user `eric' is to be delivered to `esr',
1559 but you can make this clearer by saying `user eric there is esr here',
1560 or reverse it by saying `user esr here is eric there'
1562 Legal protocol identifiers for use with the `protocol' keyword are:
1569 imap-k4 (or IMAP-K4)
1570 imap-gss (or IMAP-GSS)
1571 imap-crammd5 (or IMAP-CRAMMD5)
1572 imap-login (or IMAP-LOGIN)
1577 Legal authentication types are `password' or `kerberos'. The former
1578 specifies authentication by normal transmission of a password (the
1579 password may be plaintext or subject to protocol-specific encryption
1580 as in APOP); the second tells \fIfetchmail\fR to try to get a Kerberos
1581 ticket at the start of each query instead, and send an arbitrary
1582 string as the password.
1584 Specifying `kpop' sets POP3 protocol over port 1109 with Kerberos V4
1585 preauthentication. These defaults may be overridden by later options.
1587 There are currently four global option statements; `set logfile'
1588 followed by a string sets the same global specified by --logfile. A
1589 command-line --logfile option will override this. Also, `set daemon'
1590 sets the poll interval as --daemon does. This can be overridden by a
1591 command-line --daemon option; in particular --daemon 0 can be used to
1592 force foreground operation. The `set postmaster' statement sets the
1593 address to which multidrop mail defaults if there are no local
1594 matches. Finally, `set syslog' sends log messages to syslogd(8).
1596 .SH INTERACTION WITH RFC 822
1597 When trying to determine the originating address of a message,
1598 fetchmail looks through headers in the following order:
1608 The originating address is used for logging, and to set the MAIL FROM
1609 address when forwarding to SMTP. This order is intended to cope
1610 gracefully with receiving mailing list messages in multidrop mode. The
1611 intent is that if a local address doesn't exist, the bounce message
1612 won't be returned blindly to the author or to the list itself, but
1613 rather to the list manager (which is less annoying).
1615 In multidrop mode, destination headers are processed as follows:
1616 First, fetchmail looks for the Received: header (or whichever one is
1617 specified by the `envelope' option) to determine the local
1618 recipient address. If the mail is addressed to more than one recipient,
1619 the Received line won't contain any information regarding recipient addresses.
1621 Then fetchmail looks for the Resent-To:, Resent-Cc:, and Resent-Bcc:
1622 lines. If they exists, they should contain the final recipients and
1623 have precedence over their To:/Cc:/Bcc: counterparts. If the Resent-*
1624 lines doesn't exist, the To:, Cc:, Bcc: and Apparently-To: lines are
1625 looked for. (The presence of a Resent-To: is taken to imply that the
1626 person referred by the To: address has already received the original
1629 .SH CONFIGURATION EXAMPLES
1633 poll SERVERNAME protocol PROTOCOL username NAME password PASSWORD
1639 poll pop.provider.net protocol pop3 username "jsmith" password "secret1"
1642 Or, using some abbreviations:
1645 poll pop.provider.net proto pop3 user "jsmith" password "secret1"
1648 Multiple servers may be listed:
1651 poll pop.provider.net proto pop3 user "jsmith" pass "secret1"
1652 poll other.provider.net proto pop2 user "John.Smith" pass "My^Hat"
1655 Here's a version of those two with more whitespace and some noise words:
1658 poll pop.provider.net proto pop3
1659 user "jsmith", with password secret1, is "jsmith" here;
1660 poll other.provider.net proto pop2:
1661 user "John.Smith", with password "My^Hat", is "John.Smith" here;
1664 This version is much easier to read and doesn't cost significantly
1665 more (parsing is done only once, at startup time).
1668 If you need to include whitespace in a parameter string, enclose the
1669 string in double quotes. Thus:
1672 poll mail.provider.net with proto pop3:
1673 user "jsmith" there has password "u can't krak this"
1674 is jws here and wants mda "/bin/mail"
1677 You may have an initial server description headed by the keyword
1678 `defaults' instead of `poll' followed by a name. Such a record
1679 is interpreted as defaults for all queries to use. It may be overwritten
1680 by individual server descriptions. So, you could write:
1685 poll pop.provider.net
1687 poll mail.provider.net
1688 user "jjsmith" there has password "secret2"
1691 It's possible to specify more than one user per server (this is only
1692 likely to be useful when running fetchmail in daemon mode as root).
1693 The `user' keyword leads off a user description, and every user specification
1694 in a multi-user entry must include it. Here's an example:
1697 poll pop.provider.net proto pop3 port 3111
1698 user "jsmith" with pass "secret1" is "smith" here
1699 user jones with pass "secret2" is "jjones" here
1702 This associates the local username `smith' with the pop.provider.net
1703 username `jsmith' and the local username `jjones' with the
1704 pop.provider.net username `jones'.
1706 Here's what a simple retrieval configuration for a multi-drop mailbox
1710 poll pop.provider.net:
1711 user maildrop with pass secret1 to golux hurkle=happy snark here
1714 This says that the mailbox of account `maildrop' on the server is a
1715 multi-drop box, and that messages in it should be parsed for the
1716 server user names `golux', `hurkle', and `snark'. It further
1717 specifies that `golux' and `snark' have the same name on the
1718 client as on the server, but mail for server user `hurkle' should be
1719 delivered to client user `happy'.
1721 Here's an example of another kind of multidrop connection:
1724 poll pop.provider.net localdomains loonytoons.org toons.org:
1725 user maildrop with pass secret1 to esr * here
1728 This also says that the mailbox of account `maildrop' on the server is
1729 a multi-drop box. It tells fetchmail that any address in the
1730 loonytoons.org or toons.org domains (including subdomain addresses like
1731 `joe@daffy.loonytoons.org') should be passed through to the local SMTP
1732 listener without modification. Be careful of mail loops if you do this!
1734 Here's an example configuration using ssh. The queries go through an
1735 ssh connecting local port 1234 to port 110 on mailhost.net; the
1736 preconnect command sets up the ssh.
1739 poll mailhost.net via localhost port 1234 with proto pop3:
1740 preconnect "ssh -f -L 1234:mailhost.net:110
1741 mailhost.net sleep 20 </dev/null >/dev/null";
1745 Here's an another example configuration using ssh and the plugin option.
1746 The queries are made directly on the stdin and stdout of imapd via ssh.
1747 Note that in this setup, IMAP authentication can be skipped.
1750 poll mailhost.net with proto imap and preauth ssh:
1751 plugin "ssh %h /usr/sbin/imapd";
1754 .SH THE USE AND ABUSE OF MULTIDROP MAILBOXES
1755 Use the multiple-local-recipients feature with caution -- it can bite.
1756 Also note that all multidrop features are ineffective in ETRN mode.
1758 Also, note that in multidrop mode duplicate mails are suppressed. A
1759 piece of mail is considered duplicate if it has the same message-ID as
1760 the message immediately preceding and more than one addressee. Such
1761 runs of messages may be generated when copies of a message addressed
1762 to multiple users are delivered to a multidrop box.
1764 .SS Header vs. Envelope addresses
1765 The fundamental problem is that by having your mailserver toss several
1766 peoples' mail in a single maildrop box, you may have thrown away
1767 potentially vital information about who each piece of mail was
1768 actually addressed to (the `envelope address', as opposed to the
1769 header addresses in the RFC822 To/Cc/Bcc headers). This `envelope
1770 address' is the address you need in order to reroute mail properly.
1774 can deduce the envelope address. If the mailserver MTA is
1776 and the item of mail had just one recipient, the MTA will have written
1777 a `by/for' clause that gives the envelope addressee into its Received
1778 header. But this doesn't work reliably for other MTAs, nor if there is
1779 more than one recipient. By default, \fIfetchmail\fR looks for
1780 envelope addresses in these lines; you can restore this default with
1781 -E "Received" or \&`envelope Received'.
1783 Alternatively, some SMTP listeners and/or mail servers insert a header
1784 in each message containing a copy of the envelope addresses. This
1785 header (when it exists) is often `X-Envelope-To'. Fetchmail's
1786 assumption about this can be changed with the -E or `envelope' option.
1787 Note that writing an envelope header of this kind exposes the names of
1788 recipients (including blind-copy recipients) to all receivers of the
1789 messages; it is therefore regarded by some administrators as a
1790 security/privacy problem.
1792 A slight variation of the `X-Envelope-To' header is the `Delivered-To' put
1793 by qmail to avoid mail loops. It will probably prefix the user name with a
1794 string that normally matches the user's domain. To remove this prefix you
1795 can use the -Q or `qvirtual' option.
1797 Sometimes, unfortunately, neither of these methods works. When they
1798 all fail, fetchmail must fall back on the contents of To/Cc/Bcc
1799 headers to try to determine recipient addressees -- and these are not
1800 reliable. In particular, mailing-list software often ships mail with
1801 only the list broadcast address in the To header.
1805 cannot deduce a recipient address that is local, and the intended
1806 recipient address was anyone other than fetchmail's invoking user,
1807 mail will get lost. This is what makes the multidrop feature risky.
1809 A related problem is that when you blind-copy a mail message, the Bcc
1810 information is carried \fIonly\fR as envelope address (it's not put
1811 in the headers fetchmail can see unless there is an X-Envelope
1812 header). Thus, blind-copying to someone who gets mail over a
1813 fetchmail link will fail unless the the mailserver host routinely
1814 writes X-Envelope or an equivalent header into messages in your maildrop.
1816 .SS Good Ways To Use Multidrop Mailboxes
1817 Multiple local names can be used to administer a mailing list from the
1818 client side of a \fIfetchmail\fR collection. Suppose your name is
1819 \&`esr', and you want to both pick up your own mail and maintain a mailing
1820 list called (say) "fetchmail-friends", and you want to keep the alias
1821 list on your client machine.
1823 On your server, you can alias \&`fetchmail-friends' to `esr'; then, in
1824 your \fI.fetchmailrc\fR, declare \&`to esr fetchmail-friends here'.
1825 Then, when mail including `fetchmail-friends' as a local address
1826 gets fetched, the list name will be appended to the list of
1827 recipients your SMTP listener sees. Therefore it will undergo alias
1828 expansion locally. Be sure to include `esr' in the local alias
1829 expansion of fetchmail-friends, or you'll never see mail sent only to
1830 the list. Also be sure that your listener has the "me-too" option set
1831 (sendmail's -oXm command-line option or OXm declaration) so your name
1832 isn't removed from alias expansions in messages you send.
1834 This trick is not without its problems, however. You'll begin to see
1835 this when a message comes in that is addressed only to a mailing list
1836 you do \fInot\fR have declared as a local name. Each such message
1837 will feature an `X-Fetchmail-Warning' header which is generated
1838 because fetchmail cannot find a valid local name in the recipient
1839 addresses. Such messages default (as was described above) to being
1840 sent to the local user running
1842 but the program has no way to know that that's actually the right thing.
1844 .SS Bad Ways To Abuse Multidrop Mailboxes
1845 Multidrop mailboxes and
1847 serving multiple users in daemon mode do not mix. The problem, again, is
1848 mail from mailing lists, which typically does not have an individual
1849 recipient address on it. Unless
1851 can deduce an envelope address, such mail will only go to the account
1852 running fetchmail (probably root). Also, blind-copied users are very
1853 likely never to see their mail at all.
1855 If you're tempted to use
1857 to retrieve mail for multiple users from a single mail drop via POP or
1858 IMAP, think again (and reread the section on header and envelope
1859 addresses above). It would be smarter to just let the mail sit in the
1860 mailserver's queue and use fetchmail's ETRN mode to trigger SMTP sends
1861 periodically (of course, this means you have to poll more frequently
1862 than the mailserver's expiry period). If you can't arrange this, try
1863 setting up a UUCP feed.
1865 If you absolutely \fImust\fR use multidrop for this purpose, make sure
1866 your mailserver writes an envelope-address header that fetchmail can
1867 see. Otherwise you \fIwill\fR lose mail and it \fIwill\fR come back
1870 .SS Speeding Up Multidrop Checking
1871 Normally, when multiple user are declared
1873 extracts recipient addresses as described above and checks each host
1874 part with DNS to see if it's an alias of the mailserver. If so, the
1875 name mappings described in the to ... here declaration are done and
1876 the mail locally delivered.
1878 This is the safest but also slowest method. To speed it up,
1879 pre-declare mailserver aliases with `aka'; these are checked before
1880 DNS lookups are done. If you're certain your aka list contains
1882 DNS aliases of the mailserver (and all MX names pointing at it)
1883 you can declare `no dns' to suppress DNS lookups entirely and
1884 \fIonly\fR match against the aka list.
1887 To facilitate the use of
1889 in shell scripts, an exit code is returned to give an indication
1890 of what occurred during a given connection.
1892 The exit codes returned by
1896 One or more messages were successfully retrieved (or, if the -c option
1897 was selected, were found waiting but not retrieved).
1899 There was no mail awaiting retrieval. (There may have been old mail still
1900 on the server but not selected for retrieval.)
1902 An error was encountered when attempting to open a socket to retrieve
1903 mail. If you don't know what a socket is, don't worry about it --
1904 just treat this as an 'unrecoverable error'. This error can also be
1905 because a protocol fetchmail wants to use is not listed in /etc/services.
1907 The user authentication step failed. This usually means that a bad
1908 user-id, password, or APOP id was specified. Or it may mean that you
1909 tried to run fetchmail under circumstances where it did not have
1910 standard input attached to a terminal and could not prompt for a
1913 Some sort of fatal protocol error was detected.
1915 There was a syntax error in the arguments to
1918 The run control file had bad permissions.
1920 There was an error condition reported by the server. Can also
1923 timed out while waiting for the server.
1925 Client-side exclusion error. This means
1927 either found another copy of itself already running, or failed in such
1928 a way that it isn't sure whether another copy is running.
1930 The user authentication step failed because the server responded "lock
1931 busy". Try again after a brief pause! This error is not implemented
1932 for all protocols, nor for all servers. If not implemented for your
1933 server, "3" will be returned instead, see above. May be returned when
1934 talking to qpopper or other servers that can respond with "lock busy"
1935 or some similar text containing the word "lock".
1939 run failed while trying to do an SMTP port open or transaction.
1941 Fatal DNS error. Fetchmail encountered an error while performing
1942 a DNS lookup at startup and could not proceed.
1944 BSMTP batch file could not be opened.
1946 Poll terminated by a fetch limit (see the --fetchlimit option).
1948 Internal error. You should see a message on standard error with
1953 queries more than one host, return status is 0 if \fIany\fR query
1954 successfully retrieved mail. Otherwise the returned error status is
1955 that of the last host queried.
1958 Eric S. Raymond <esr@snark.thyrsus.com>. Too many other people to
1959 name here have contributed code and patches.
1960 This program is descended from and replaces
1962 by Carl Harris <ceharris@mal.com>; the internals have become quite different,
1963 but some of its interface design is directly traceable to that
1969 default run control file
1972 default location of file associating hosts with last message IDs seen
1973 (used only with newer RFC1725-compliant POP3 servers supporting the
1977 lock file to help prevent concurrent runs (non-root mode).
1980 your FTP run control file, which (if present) will be searched for
1981 passwords as a last resort before prompting for one interactively.
1983 /var/run/fetchmail.pid
1984 lock file to help prevent concurrent runs (root mode, Linux systems).
1987 lock file to help prevent concurrent runs (root mode, systems without /var/run).
1990 If the FETCHMAILUSER variable is set, it is used as the name of the
1991 calling user (default local name) for purposes such as mailing error
1992 notifications. Otherwise, if either the LOGNAME or USER variable is
1993 correctly set (e.g. the corresponding UID matches the session user ID)
1994 then that name is used as the default local name. Otherwise
1995 \fBgetpwuid\fR(3) must be able to retrieve a password entry for the
1996 session ID (this elaborate logic is designed to handle the case of
1997 multiple names per userid gracefully).
1999 If the environment variable FETCHMAILHOME is set to a valid and
2000 existing directory name, the .fetchmailrc and .fetchids and
2001 \&.fetchmail.pid files are put there instead of in the invoking user's
2002 home directory (and lose the leading dots on theirt names). The
2003 \&.netrc file is looked for in the the invoking user's home directory
2004 regardless of FETCHMAILHOME's setting.
2009 daemon is running as root, SIGHUP wakes it up from its sleep phase and
2010 forces a poll of all non-skipped servers (this is in accordance with
2011 the usual conventions for system daemons).
2015 is running in daemon mode as non-root, use SIGUSR1 to wake it (this is
2016 so SIGHUP due to logout can retain the default action of killing it).
2020 in foreground while a background fetchmail is running will do
2021 whichever of these is appropriate to wake it up.
2023 .SH BUGS AND KNOWN PROBLEMS
2024 The RFC822 address parser used in multidrop mode chokes on some
2025 @-addresses that are technically legal but bizarre. Strange uses of
2026 quoting and embedded comments are likely to confuse it.
2028 In a message with multiple envelope headers, only the last one
2029 processed will be visible to fetchmail. To get around this, use a
2030 mailserver-side filter that consolidates the contents of all envelope
2031 headers into a single one (procmail, mailagent, or maildrop can be
2032 programmed to do this fairly easily).
2034 Use of any of the supported protocols other than POP3 with OTP or RPA,
2035 APOP, KPOP, IMAP-K4, IMAP-GSS, IMAP-CRAMMD5, or ETRN requires that the
2036 program send unencrypted passwords over the TCP/IP connection to the
2037 mailserver. This creates a risk that name/password pairs might be
2038 snaffled with a packet sniffer or more sophisticated monitoring
2039 software. Under Linux and FreeBSD, the --interface option can be used
2040 to restrict polling to availability of a specific interface device
2041 with a specific local or remote IP address, but snooping is still
2042 possible if (a) either host has a network device that can be opened
2043 in promiscuous mode, or (b) the intervening network link can be tapped.
2045 Use of the %F or %T escapes in an mda option could open a security
2046 hole, because they pass text manipulable by an attacker to a shell
2047 command. Potential shell characters are replaced by `_' before
2048 execution. The hole is further reduced by the fact that fetchmail
2049 temporarily discards any suid privileges it may have while running the
2050 MDA. For maximum safety, however, don't use an mda command containing
2051 %F or %T when fetchmail is run from the root account itself.
2053 Fetchmail's method of sending bouncemail and spambounce requires that
2054 port 25 of localhost be available for sending mail via SMTP.
2058 while a background instance is running and break the syntax, the
2059 background instance will die silently. Unfortunately, it can't
2060 die noisily because we don't yet know whether syslog should be enabled.
2062 The RFC 2177 IDLE support is flaky. It sort of works, but may generate
2063 spurious socket error messages or silently hang in the presence of
2064 various network or server errors.
2066 The combination of using a remote name with embedded spaces and POP3
2067 UIDs will not work; the UIDL-handling code will core-dump while trying
2068 to read in what it sees as malformed .fetchids lines, typically
2069 on the second poll after startup.
2071 The UIDL code is generally flaky and tends to lose its state on errors
2072 and line drops (so that old messages are re-seen). If this happens to
2073 you, switch to IMAP4.
2075 The `principal' option only handles Kerberos IV, not V.
2077 Send comments, bug reports, gripes, and the like to the
2078 fetchmail-friends list <fetchmail-friends@ccil.org>. An HTML FAQ is
2079 available at the fetchmail home page; surf to
2080 http://www.tuxedo.org/~esr/fetchmail or do a WWW search for pages with
2081 `fetchmail' in their titles.
2084 mutt(1), elm(1), mail(1), sendmail(8), popd(8), imapd(8)
2085 .SH APPLICABLE STANDARDS
2088 RFC 821, RFC 1869, RFC 1652, RFC 1870, RFC1983, RFC 1985
2091 RFC 822, RFC 1892, RFC 1894
2097 RFC 1081, RFC 1225, RFC 1460, RFC 1725, RFC 1939, RFC 1957, RFC2195, RFC 2449
2100 RFC 1460, RFC 1725, RFC 1939
2109 RFC 1730, RFC 1731, RFC 1732, RFC 2060, RFC 2061, RFC 2195, RFC 2177,
projects / ~andy / fetchmail / blob