'\" t
.\" ** The above line should force tbl to be used as a preprocessor **
.\"
-.\" Manual page in man(7) format with tbl(1) macros for fetchmail
+.\" Manual page in man(7) format with tbl(1) and groff_www(7)
+.\" macros for fetchmail
.\"
.\" For license terms, see the file COPYING in this directory.
.\"
-.TH fetchmail 1
+.\"
+.\" Load www macros to process .URL requests, this requires groff:
+.mso www.tmac
+.\"
+.TH fetchmail 1 "fetchmail 6.3.23" "fetchmail" "fetchmail reference manual"
+
.SH NAME
fetchmail \- fetch mail from a POP, IMAP, ETRN, or ODMR-capable server
.SH SYNOPSIS
-\fBfetchmail\fR [\fIoption...\fR] [\fImailserver...\fR]
+\fBfetchmail\fP [\fIoption...\fP] [\fImailserver...\fP]
.br
-\fBfetchmailconf\fR
+\fBfetchmailconf\fP
.SH DESCRIPTION
-.I fetchmail
-is a mail-retrieval and forwarding utility; it fetches mail from
-remote mailservers and forwards it to your local (client) machine's
-delivery system. You can then handle the retrieved mail using normal
-mail user agents such as \fImutt\fR(1), \fIelm\fR(1) or \fIMail\fR(1).
-The \fIfetchmail\fR utility can be run in a daemon mode to repeatedly
-poll one or more systems at a specified interval.
+\fBfetchmail\fP is a mail-retrieval and forwarding utility; it fetches
+mail from remote mailservers and forwards it to your local (client)
+machine's delivery system. You can then handle the retrieved mail using
+normal mail user agents such as \fBmutt\fP(1), \fBelm\fP(1) or
+\fBMail\fP(1). The \fBfetchmail\fP utility can be run in a daemon mode
+to repeatedly poll one or more systems at a specified interval.
+.PP
+The \fBfetchmail\fP program can gather mail from servers supporting any
+of the common mail-retrieval protocols: POP2 (legacy, to be removed from
+future release), POP3, IMAP2bis, IMAP4, and IMAP4rev1. It can also use
+the ESMTP ETRN extension and ODMR. (The RFCs describing all these
+protocols are listed at the end of this manual page.)
+.PP
+While \fBfetchmail\fP is primarily intended to be used over on-demand
+TCP/IP links (such as SLIP or PPP connections), it may also be useful as
+a message transfer agent for sites which refuse for security reasons to
+permit (sender-initiated) SMTP transactions with sendmail.
+
+.SS SUPPORT, TROUBLESHOOTING
.PP
-The
-.I fetchmail
-program can gather mail from servers supporting any of the common
-mail-retrieval protocols: POP2 (legacy, to be removed from future
-release), POP3, IMAP2bis, IMAP4, and IMAP4rev1.
-It can also use the ESMTP ETRN extension and ODMR. (The RFCs describing all
-these protocols are listed at the end of this manual page.)
-.PP
-While
-.I fetchmail
-is primarily intended to be used over on-demand TCP/IP links (such as
-SLIP or PPP connections), it may also be useful as a message transfer
-agent for sites which refuse for security reasons to permit
-(sender-initiated) SMTP transactions with sendmail.
+For troubleshooting, tracing and debugging, you need to increase
+fetchmail's verbosity to actually see what happens. To do that, please
+run \fBboth of the two following commands,
+adding all of the options you'd normally use.\fP
+
+.IP
+.nf
+env LC_ALL=C fetchmail \-V \-v \-\-nodetach \-\-nosyslog
+.fi
+.IP
+(This command line prints in English how fetchmail understands your
+configuration.)
+
+.IP
+.nf
+env LC_ALL=C fetchmail \-vvv \-\-nodetach \-\-nosyslog
+.fi
+.IP
+(This command line actually runs fetchmail with verbose English output.)
.PP
-If
-.I fetchmail
-is used with a POP or an IMAP server, it has two fundamental modes of
-operation for each user account from which it retrieves mail:
-\fIsingledrop\fR- and \fImultidrop\fR-mode. In singledrop-mode,
-.I fetchmail
-assumes that all messages in the user's account are intended for a single
-recipient. An individual mail message will not be inspected for recipient
-information, rather, the identity of the recipient will either default to
-the local user currently executing \fIfetchmail\fR,
-or else will need to be explicitly specified in the configuration file.
-Singledrop-mode is used when the fetchmailrc configuration contains at
-most a single local user specification for a given server account.
-.PP
-With multidrop-mode,
-.I fetchmail
-is not able to assume that there is only a single recipient, but rather
-that the mail server account actually contains mail intended for any
-number of different recipients. Therefore,
-.I fetchmail
-must attempt to deduce the proper "envelope recipient" from the mail
-headers of each message. In this mode of operation
-.I fetchmail
-almost resembles an MTA, however it is important to note that neither
-the POP nor IMAP protocols were intended for use in this fashion, and
-hence envelope information is not directly available. Instead,
-.I fetchmail
-must resort to a process of informed guess-work in an attempt to
-discover the true envelope recipient of a message. Even if this
-information is present in the headers, the process can
-be error-prone and is dependent upon the specific mail server used
-for mail retrieval. Multidrop-mode is used when more than one local
-user is specified for a particular server account in the configuration
-file. Note that the forgoing discussion of singledrop- and
-multidrop-modes does not apply to the ESMTP ETRN or ODMR retrieval
-methods, since they are based upon the SMTP protocol which
-specifically provides the envelope recipient to \fIfetchmail\fR.
-.PP
-As each message is retrieved \fIfetchmail\fR normally delivers it via SMTP to
-port 25 on the machine it is running on (localhost), just as though it
-were being passed in over a normal TCP/IP link. \fIfetchmail\fR provides
-the SMTP server with an envelope recipient derived in the manner described
-previously. The mail will then be
-delivered locally via your system's MDA (Mail Delivery Agent, usually
-\fIsendmail\fR(8) but your system may use a different one such
-as \fIsmail\fR, \fImmdf\fR, \fIexim\fR, \fIpostfix\fR, or \fIqmail\fR). All the
-delivery-control mechanisms (such as \fI.forward\fR files) normally
-available through your system MDA and local delivery agents will
-therefore work automatically.
-.PP
-If no port 25 listener is available, but your fetchmail configuration
-was told about a reliable local MDA, it will use that MDA for local
-delivery instead.
-.PP
-If the program
-.I fetchmailconf
-is available, it will assist you in setting up and editing a
-fetchmailrc configuration. It runs under the X window system and
-requires that the language Python and the Tk toolkit be present on your
-system. If you are first setting up fetchmail for single-user mode, it
-is recommended that you use Novice mode. Expert mode provides complete
-control of fetchmail configuration, including the multidrop features.
-In either case, the 'Autoprobe' button will tell you the most capable
-protocol a given mailserver supports, and warn you of potential problems
-with that server.
+Also see
+.URL "http://fetchmail.berlios.de/fetchmail-FAQ.html#G3" "item #G3 in fetchmail's FAQ"
+.PP
+You can omit the LC_ALL=C part above if you want output in the local
+language (if supported). However if you are posting to mailing lists,
+please leave it in. The maintainers do not necessarily understand your
+language, please use English.
+
+
+
+.SS CONCEPTS
+If \fBfetchmail\fP is used with a POP or an IMAP server (but not with
+ETRN or ODMR), it has two fundamental modes of operation for each user
+account from which it retrieves mail: \fIsingledrop\fP- and
+\fImultidrop\fP-mode.
+.IP "In singledrop-mode,"
+\fBfetchmail\fP assumes that all messages in the user's account
+(mailbox) are intended for a single recipient. The identity of the
+recipient will either default to the local user currently executing
+\fBfetchmail\fP, or will need to be explicitly specified in the
+configuration file.
+.IP
+\fBfetchmail\fP uses singledrop-mode when the fetchmailrc configuration
+contains at most a single local user specification for a given server
+account.
+.IP "In multidrop-mode,"
+\fBfetchmail\fP assumes that the mail server account actually contains
+mail intended for any number of different recipients. Therefore,
+\fBfetchmail\fP must attempt to deduce the proper "envelope recipient"
+from the mail headers of each message. In this mode of operation,
+\fBfetchmail\fP almost resembles a mail transfer agent (MTA).
+.IP
+Note that neither the POP nor IMAP protocols were intended for use in
+this fashion, and hence envelope information is often not directly
+available. The ISP must stores the envelope information in some message
+header \fBand\fP. The ISP must also store one copy of the message per
+recipient. If either of the conditions is not fulfilled, this process is
+unreliable, because \fBfetchmail\fP must then resort to guessing the
+true envelope recipient(s) of a message. This usually fails for mailing
+list messages and Bcc:d mail, or mail for multiple recipients in your
+domain.
+.IP
+\fBfetchmail\fP uses multidrop-mode when more than one local user and/or
+a wildcard is specified for a particular server account in the
+configuration file.
+.IP "In ETRN and ODMR modes,"
+these considerations do not apply, as these protocols are based on SMTP,
+which provides explicit envelope recipient information. These protocols
+always support multiple recipients.
+.PP
+As each message is retrieved, \fBfetchmail\fP normally delivers it via
+SMTP to port 25 on the machine it is running on (localhost), just as
+though it were being passed in over a normal TCP/IP link.
+\fBfetchmail\fP provides the SMTP server with an envelope recipient
+derived in the manner described previously. The mail will then be
+delivered according to your MTA's rules (the Mail Transfer Agent is
+usually \fBsendmail\fP(8), \fBexim\fP(8), or \fBpostfix\fP(8)).
+Invoking your system's MDA (Mail Delivery Agent) is the duty of your
+MTA. All the delivery-control mechanisms (such as \fI.forward\fP files)
+normally available through your system MTA and local delivery agents
+will therefore be applied as usual.
+.PP
+If your fetchmail configuration sets a local MDA (see the \-\-mda
+option), it will be used directly instead of talking SMTP to port 25.
+.PP
+If the program \fBfetchmailconf\fP is available, it will assist you in
+setting up and editing a fetchmailrc configuration. It runs under the X
+window system and requires that the language Python and the Tk toolkit
+(with Python bindings) be present on your system. If you are first
+setting up fetchmail for single-user mode, it is recommended that you
+use Novice mode. Expert mode provides complete control of fetchmail
+configuration, including the multidrop features. In either case,
+the 'Autoprobe' button will tell you the most capable protocol a given
+mailserver supports, and warn you of potential problems with that
+server.
.SH GENERAL OPERATION
-The behavior of
-.I fetchmail
-is controlled by command-line options and a run control file,
-.IR ~/.fetchmailrc\fR ,
+The behavior of \fBfetchmail\fP is controlled by command-line options and a
+run control file, \fI~/.fetchmailrc\fP,
the syntax of which we describe in a later section (this file is what
-the \fIfetchmailconf\fR program edits). Command-line options override
-.I ~/.fetchmailrc
-declarations.
+the \fBfetchmailconf\fP program edits). Command-line options override
+\fI~/.fetchmailrc\fP declarations.
.PP
-Each server name that you specify following the options on the
-command line will be queried. If you don't specify any servers
-on the command line, each 'poll' entry in your
-.I ~/.fetchmailrc
-file will be queried.
+Each server name that you specify following the options on the command
+line will be queried. If you don't specify any servers on the command
+line, each 'poll' entry in your \fI~/.fetchmailrc\fP file will be
+queried.
.PP
-To facilitate the use of
-.I fetchmail
-in scripts and pipelines, it returns an appropriate exit code upon
-termination -- see EXIT CODES below.
+To facilitate the use of \fBfetchmail\fP in scripts and pipelines, it
+returns an appropriate exit code upon termination -- see EXIT CODES
+below.
.PP
-The following options modify the behavior of \fIfetchmail\fR. It is
+The following options modify the behavior of \fBfetchmail\fP. It is
seldom necessary to specify any of these once you have a
-working \fI.fetchmailrc\fR file set up.
+working \fI.fetchmailrc\fP file set up.
.PP
Almost all options have a corresponding keyword which can be used to
-declare them in a
-.I .fetchmailrc
-file.
+declare them in a \fI.fetchmailrc\fP file.
.PP
Some special options are not covered here, but are documented instead
in sections on AUTHENTICATION and DAEMON MODE which follow.
.SS General Options
.TP
.B \-V | \-\-version
-Displays the version information for your copy of
-.IR fetchmail .
-No mail fetch is performed.
-Instead, for each server specified, all the option information
-that would be computed if
-.I fetchmail
-were connecting to that server is displayed. Any non-printables in
-passwords or other string names are shown as backslashed C-like
-escape sequences. This option is useful for verifying that your
-options are set the way you want them.
+Displays the version information for your copy of \fBfetchmail\fP. No mail
+fetch is performed. Instead, for each server specified, all the option
+information that would be computed if \fBfetchmail\fP were connecting to that
+server is displayed. Any non-printables in passwords or other string names
+are shown as backslashed C-like escape sequences. This option is useful for
+verifying that your options are set the way you want them.
.TP
.B \-c | \-\-check
Return a status code to indicate whether there is mail waiting,
.B \-s | \-\-silent
Silent mode. Suppresses all progress/status messages that are
normally echoed to standard output during a fetch (but does not
-suppress actual error messages). The --verbose option overrides this.
+suppress actual error messages). The \-\-verbose option overrides this.
.TP
.B \-v | \-\-verbose
-Verbose mode. All control messages passed between
-.I fetchmail
-and the mailserver are echoed to stdout. Overrides --silent.
-Doubling this option (-v -v) causes extra diagnostic information
+Verbose mode. All control messages passed between \fBfetchmail\fP
+and the mailserver are echoed to stdout. Overrides \-\-silent.
+Doubling this option (\-v \-v) causes extra diagnostic information
to be printed.
+.TP
+.B \-\-nosoftbounce
+(since v6.3.10, Keyword: set no softbounce, since v6.3.10)
+.br
+Hard bounce mode. All permanent delivery errors cause messages to be
+deleted from the upstream server, see "no softbounce" below.
+.TP
+.B \-\-softbounce
+(since v6.3.10, Keyword: set softbounce, since v6.3.10)
+.br
+Soft bounce mode. All permanent delivery errors cause messages to be
+left on the upstream server if the protocol supports that. Default to
+match historic fetchmail documentation, to be changed to hard bounce
+mode in the next fetchmail release.
.SS Disposal Options
.TP
-.B \-a | \-\-all
-(Keyword: fetchall)
+.B \-a | \-\-all | (since v6.3.3) \-\-fetchall
+(Keyword: fetchall, since v3.0)
+.br
Retrieve both old (seen) and new messages from the mailserver. The
default is to fetch only messages the server has not marked seen.
Under POP3, this option also forces the use of RETR rather than TOP.
-Note that POP2 retrieval behaves as though --all is always on (see
+Note that POP2 retrieval behaves as though \-\-all is always on (see
RETRIEVAL FAILURE MODES below) and this option does not work with ETRN
-or ODMR.
+or ODMR. While the \-a and \-\-all command-line and fetchall rcfile
+options have been supported for a long time, the \-\-fetchall
+command-line option was added in v6.3.3.
.TP
.B \-k | \-\-keep
(Keyword: keep)
+.br
Keep retrieved messages on the remote mailserver. Normally, messages
are deleted from the folder on the mailserver after they have been retrieved.
-Specifying the
-.B keep
-option causes retrieved messages to remain in your folder on the
-mailserver. This option does not work with ETRN or ODMR.
+Specifying the \fBkeep\fP option causes retrieved messages to remain in
+your folder on the mailserver. This option does not work with ETRN or
+ODMR. If used with POP3, it is recommended to also specify the \-\-uidl
+option or uidl keyword.
.TP
.B \-K | \-\-nokeep
(Keyword: nokeep)
+.br
Delete retrieved messages from the remote mailserver. This
option forces retrieved mail to be deleted. It may be useful if
-you have specified a default of \fBkeep\fR in your
-\&\fI.fetchmailrc\fR. This option is forced on with ETRN and ODMR.
+you have specified a default of \fBkeep\fP in your
+\&\fI.fetchmailrc\fP. This option is forced on with ETRN and ODMR.
.TP
.B \-F | \-\-flush
+(Keyword: flush)
+.br
POP3/IMAP only. This is a dangerous option and can cause mail loss when
used improperly. It deletes old (seen) messages from the mailserver
-before retrieving new messages. Warning: This can cause mail loss if
+before retrieving new messages. \fBWarning:\fP This can cause mail loss if
you check your mail with other clients than fetchmail, and cause
-fetchmail to delete a message it had never fetched before. Similarly, if
-your local MTA hangs and fetchmail is aborted, the next time you run
-fetchmail, it will delete mail that was never delivered to you. You
-should probably not use this option in your configuration file. What you
-probably want is the default setting: if you don't specify '-k', then
-fetchmail will automatically delete messages after successful
-delivery. This option does not work with ETRN and ODMR.
+fetchmail to delete a message it had never fetched before. It can also
+cause mail loss if the mail server marks the message seen after
+retrieval (IMAP2 servers). You should probably not use this option in your
+configuration file. If you use it with POP3, you must use the 'uidl'
+option. What you probably want is the default setting: if you don't
+specify '\-k', then fetchmail will automatically delete messages after
+successful delivery.
.TP
.B \-\-limitflush
POP3/IMAP only, since version 6.3.0. Delete oversized messages from the
mailserver before retrieving new messages. The size limit should be
-separately sepecified with the --limit option. This option does not
+separately specified with the \-\-limit option. This option does not
work with ETRN or ODMR.
.SS Protocol and Query Options
.TP
.B \-p <proto> | \-\-proto <proto> | \-\-protocol <proto>
(Keyword: proto[col])
+.br
Specify the protocol to use when communicating with the remote
mailserver. If no protocol is specified, the default is AUTO.
-.I proto
-may be one of the following:
+\fBproto\fP may be one of the following:
.RS
.IP AUTO
Tries IMAP, POP3, and POP2 (skipping any of these for which support
Post Office Protocol 3
.IP APOP
Use POP3 with old-fashioned MD5-challenge authentication.
+Considered not resistant to man-in-the-middle attacks.
.IP RPOP
Use POP3 with RPOP authentication.
.IP KPOP
.IP SDPS
Use POP3 with Demon Internet's SDPS extensions.
.IP IMAP
-IMAP2bis, IMAP4, or IMAP4rev1 (\fIfetchmail\fR autodetects their capabilities).
+IMAP2bis, IMAP4, or IMAP4rev1 (\fBfetchmail\fP automatically detects their capabilities).
.IP ETRN
Use the ESMTP ETRN option.
.IP ODMR
Use the the On-Demand Mail Relay ESMTP profile.
.RE
-.P
+.PP
All these alternatives work in basically the same way (communicating
with standard server daemons to fetch mail already delivered to a
mailbox on the server) except ETRN and ODMR. The ETRN mode
.TP
.B \-U | \-\-uidl
(Keyword: uidl)
+.br
Force UIDL use (effective only with POP3). Force client-side tracking
of 'newness' of messages (UIDL stands for "unique ID listing" and is
described in RFC1939). Use with 'keep' to use a mailbox as a baby
is logged, unless error logging is done through syslog while running in
daemon mode. Note that fetchmail may automatically enable this option
depending on upstream server capabilities. Note also that this option
-may be removed and forced enabled in a future fetchmail version.
-
+may be removed and forced enabled in a future fetchmail version. See
+also: \-\-idfile.
+.TP
+.B \-\-idle (since 6.3.3)
+(Keyword: idle, since before 6.0.0)
+.br
+Enable IDLE use (effective only with IMAP). Note that this works with
+only one folder at a given time. While the idle rcfile keyword had been
+supported for a long time, the \-\-idle command-line option was added in
+version 6.3.3. IDLE use means that fetchmail tells the IMAP server to
+send notice of new messages, so they can be retrieved sooner than would
+be possible with regular polls.
.TP
-.B \-\-service <servicename>
+.B \-P <portnumber> | \-\-service <servicename>
(Keyword: service) Since version 6.3.0.
+.br
The service option permits you to specify a service name to connect to.
You can specify a decimal port number here, if your services database
lacks the required service-port assignments. See the FAQ item R12 and
the \-\-ssl documentation for details. This replaces the older \-\-port
option.
.TP
-.B \-
P <portnumber> | \-\-port <portnumber>
+.B \-\-port <portnumber>
(Keyword: port)
+.br
Obsolete version of \-\-service that does not take service names.
-.B Note:
-this option may be removed from a future version.
+\fBNote:\fP this option may be removed from a future version.
.TP
.B \-\-principal <principal>
(Keyword: principal)
+.br
The principal option permits you to specify a service principal for
mutual authentication. This is applicable to POP3 or IMAP with Kerberos
-authentication.
+4 authentication only. It does not apply to Kerberos 5 or GSSAPI. This
+option may be removed in a future fetchmail version.
.TP
.B \-t <seconds> | \-\-timeout <seconds>
(Keyword: timeout)
+.br
The timeout option allows you to set a server-nonresponse
timeout in seconds. If a mailserver does not send a greeting message
or respond to commands for the given number of seconds,
-\fIfetchmail\fR will hang up on it. Without such a timeout
-\fIfetchmail\fR might hang up indefinitely trying to fetch mail from a
-down host. This would be particularly annoying for a \fIfetchmail\fR
-running in background. There is a default timeout which fetchmail\~-V
-will report. If a given connection receives too many timeouts in
-succession, fetchmail will consider it wedged and stop retrying,
-the calling user will be notified by email if this happens.
+\fBfetchmail\fP will drop the connection to it. Without such a timeout
+\fBfetchmail\fP might hang until the TCP connection times out, trying to fetch
+mail from a down host, which may be very long.
+This would be particularly annoying for a \fBfetchmail\fP running in the
+background. There is a default timeout which fetchmail\~\-V will report. If a
+given connection receives too many timeouts in succession, fetchmail will
+consider it wedged and stop retrying. The calling user will be notified by
+email if this happens.
+.IP
+Beginning with fetchmail 6.3.10, the SMTP client uses the recommended minimum
+timeouts from RFC-5321 while waiting for the SMTP/LMTP server it is talking to.
+You can raise the timeouts even more, but you cannot shorten them. This is to
+avoid a painful situation where fetchmail has been configured with a short
+timeout (a minute or less), ships a long message (many MBytes) to the local
+MTA, which then takes longer than timeout to respond "OK", which it eventually
+will; that would mean the mail gets delivered properly, but fetchmail cannot
+notice it and will thus refetch this big message over and over again.
.TP
.B \-\-plugin <command>
-(Keyword: plugin) The plugin option allows you to use an external
-program to establish the TCP connection. This is useful if you want
-to use socks, SSL, ssh, or need some special firewalling setup. The
-program will be looked up in $PATH and can optionally be passed the
-hostname and port as arguments using "%h" and "%p" respectively (note
-that the interpolation logic is rather primitive, and these token must
+(Keyword: plugin)
+.br
+The plugin option allows you to use an external program to establish the TCP
+connection. This is useful if you want to use ssh, or need some special
+firewalling setup. The program will be looked up in $PATH and can optionally
+be passed the hostname and port as arguments using "%h" and "%p" respectively
+(note that the interpolation logic is rather primitive, and these tokens must
be bounded by whitespace or beginning of string or end of string).
Fetchmail will write to the plugin's stdin and read from the plugin's
stdout.
.TP
.B \-\-plugout <command>
(Keyword: plugout)
+.br
Identical to the plugin option above, but this one is used for the SMTP
-connections (which will probably not need it, so it has been separated
-from plugin).
+connections.
.TP
.B \-r <name> | \-\-folder <name>
(Keyword: folder[s])
+.br
Causes a specified non-default mail folder on the mailserver (or
comma-separated list of folders) to be retrieved. The syntax of the
folder name is server-dependent. This option is not available under
.TP
.B \-\-tracepolls
(Keyword: tracepolls)
-Tell fetchmail to poll trace information in the form 'polling %s
-account %s' to the Received line it generates, where the %s parts are
-replaced by the user's remote name and the poll label (the Received
-header also normally includes the server's true name). This can be
-used to facilitate mail filtering based on the account it is being
-received from.
+.br
+Tell fetchmail to poll trace information in the form 'polling
+account %s' and 'folder %s' to the Received line it generates,
+where the %s parts are replaced by the user's remote name, the poll
+label, and the folder (mailbox) where available (the Received header
+also normally includes the server's true name). This can be used to
+facilitate mail filtering based on the account it is being received
+from. The folder information is written only since version 6.3.4.
.TP
.B \-\-ssl
(Keyword: ssl)
-Causes the connection to the mail server to be encrypted via SSL. Connect
-to the server using the specified base protocol over a connection secured
-by SSL. SSL support must be present at the server.
-.sp
+.br
+Causes the connection to the mail server to be encrypted
+via SSL. Connect to the server using the specified base protocol over a
+connection secured by SSL. This option defeats opportunistic starttls
+negotiation. It is highly recommended to use \-\-sslproto 'SSL3'
+\-\-sslcertck to validate the certificates presented by the server and
+defeat the obsolete SSLv2 negotiation. More information is available in
+the \fIREADME.SSL\fP file that ships with fetchmail.
+.IP
+Note that fetchmail may still try to negotiate SSL through starttls even
+if this option is omitted. You can use the \-\-sslproto option to defeat
+this behavior or tell fetchmail to negotiate a particular SSL protocol.
+.IP
If no port is specified, the connection is attempted to the well known
port of the SSL version of the base protocol. This is generally a
different port than the port used by the base protocol. For IMAP, this
is port 143 for the clear protocol and port 993 for the SSL secured
-protocol, for POP3, it is port 110 for the cleartext and port 995 for
+protocol, for POP3, it is port 110 for the clear text and port 995 for
the encrypted variant.
-.sp
+.IP
If your system lacks the corresponding entries from /etc/services, see
the \-\-service option and specify the numeric port number as given in
the previous paragraph (unless your ISP had directed you to different
.TP
.B \-\-sslcert <name>
(Keyword: sslcert)
-Specifies the file name of the client side public SSL certificate. Some
-SSL encrypted servers may require client side keys and certificates for
-authentication. In most cases, this is optional. This specifies
-the location of the public key certificate to be presented to the server
-at the time the SSL session is established. It is not required (but may
-be provided) if the server does not require it. Some servers may
-require it, some servers may request it but not require it, and some
-servers may not request it at all. It may be the same file
-as the private key (combined key and certificate file) but this is not
-recommended.
+.br
+For certificate-based client authentication. Some SSL encrypted servers
+require client side keys and certificates for authentication. In most
+cases, this is optional. This specifies the location of the public key
+certificate to be presented to the server at the time the SSL session is
+established. It is not required (but may be provided) if the server
+does not require it. It may be the same file as the private key
+(combined key and certificate file) but this is not recommended. Also
+see \-\-sslkey below.
+.sp
+\fBNOTE:\fP If you use client authentication, the user name is fetched
+from the certificate's CommonName and overrides the name set with
+\-\-user.
.TP
.B \-\-sslkey <name>
(Keyword: sslkey)
+.br
Specifies the file name of the client side private SSL key. Some SSL
-encrypted servers may require client side keys and certificates for
+encrypted servers require client side keys and certificates for
authentication. In most cases, this is optional. This specifies
the location of the private key used to sign transactions with the server
at the time the SSL session is established. It is not required (but may
-be provided) if the server does not require it. Some servers may
-require it, some servers may request it but not require it, and some
-servers may not request it at all. It may be the same file
+be provided) if the server does not require it. It may be the same file
as the public key (combined key and certificate file) but this is not
-recommended. If a password is required to unlock the key, it will be
-prompted for at the time just prior to establishing the session to the
-server. This can cause some complications in daemon mode.
+recommended.
+.IP
+If a password is required to unlock the key, it will be prompted for at
+the time just prior to establishing the session to the server. This can
+cause some complications in daemon mode.
+.IP
+Also see \-\-sslcert above.
.TP
.B \-\-sslproto <name>
(Keyword: sslproto)
-Forces an SSL protocol. Possible values are '\fBssl2\fR',
-\&'\fBssl3\fR', '\fBssl23\fR', and '\fBtls1\fR'. Try this if the default
-handshake does not work for your server. To defeat automatic TLSv1
-negotiation when the server advertises STARTTLS or STLS, use \fB''\fR or
-\&'\fBssl23\fR'. The default is to try appropriate protocols depending
-on context.
+.br
+Forces an SSL/TLS protocol. Possible values are \fB''\fP,
+\&'\fBSSL2\fP' (not supported on all systems),
+\&'\fBSSL23\fP', (use of these two values is discouraged
+and should only be used as a last resort) \&'\fBSSL3\fP', and
+\&'\fBTLS1\fP'. The default behaviour if this option is unset is: for
+connections without \-\-ssl, use \&'\fBTLS1\fP' so that fetchmail will
+opportunistically try STARTTLS negotiation with TLS1. You can configure
+this option explicitly if the default handshake (TLS1 if \-\-ssl is not
+used) does not work for your server.
+.IP
+Use this option with '\fBTLS1\fP' value to enforce a STARTTLS
+connection. In this mode, it is highly recommended to also use
+\-\-sslcertck (see below). Note that this will then cause fetchmail
+v6.3.19 to force STARTTLS negotiation even if it is not advertised by
+the server.
+.IP
+To defeat opportunistic TLSv1 negotiation when the server advertises
+STARTTLS or STLS, and use a cleartext connection use \fB''\fP. This
+option, even if the argument is the empty string, will also suppress the
+diagnostic 'SERVER: opportunistic upgrade to TLS.' message in verbose
+mode. The default is to try appropriate protocols depending on context.
.TP
.B \-\-sslcertck
(Keyword: sslcertck)
+.br
Causes fetchmail to strictly check the server certificate against a set of
-local trusted certificates (see the \fBsslcertpath\fR option). If the server
-certificate is not signed by one of the trusted ones (directly or indirectly),
-the SSL connection will fail. This checking should prevent man-in-the-middle
-attacks against the SSL connection. Note that CRLs are seemingly not currently
-supported by OpenSSL in certificate verification! Your system clock should
-be reasonably accurate when using this option!
+local trusted certificates (see the \fBsslcertfile\fP and \fBsslcertpath\fP
+options). If the server certificate cannot be obtained or is not signed by one
+of the trusted ones (directly or indirectly), the SSL connection will fail,
+regardless of the \fBsslfingerprint\fP option.
+.IP
+Note that CRL (certificate revocation lists) are only supported in
+OpenSSL 0.9.7 and newer! Your system clock should also be reasonably
+accurate when using this option.
+.IP
+Note that this optional behavior may become default behavior in future
+fetchmail versions.
+.TP
+.B \-\-sslcertfile <file>
+(Keyword: sslcertfile, since v6.3.17)
+.br
+Sets the file fetchmail uses to look up local certificates. The default is
+empty. This can be given in addition to \fB\-\-sslcertpath\fP below, and
+certificates specified in \fB\-\-sslcertfile\fP will be processed before those
+in \fB\-\-sslcertpath\fP. The option can be used in addition to
+\fB\-\-sslcertpath\fP.
+.IP
+The file is a text file. It contains the concatenation of trusted CA
+certificates in PEM format.
+.IP
+Note that using this option will suppress loading the default SSL trusted CA
+certificates file unless you set the environment variable
+\fBFETCHMAIL_INCLUDE_DEFAULT_X509_CA_CERTS\fP to a non-empty value.
.TP
.B \-\-sslcertpath <directory>
(Keyword: sslcertpath)
-Sets the directory fetchmail uses to look up local certificates. The default
-is your OpenSSL default one. The directory must be hashed as OpenSSL expects
-it - every time you add or modify a certificate in the directory, you need
-to use the \fBc_rehash\fR tool (which comes with OpenSSL in the tools/
-subdirectory).
+.br
+Sets the directory fetchmail uses to look up local certificates. The default is
+your OpenSSL default directory. The directory must be hashed the way OpenSSL
+expects it - every time you add or modify a certificate in the directory, you
+need to use the \fBc_rehash\fP tool (which comes with OpenSSL in the tools/
+subdirectory). Also, after OpenSSL upgrades, you may need to run
+\fBc_rehash\fP; particularly when upgrading from 0.9.X to 1.0.0.
+.IP
+This can be given in addition to \fB\-\-sslcertfile\fP above, which see for
+precedence rules.
+.IP
+Note that using this option will suppress adding the default SSL trusted CA
+certificates directory unless you set the environment variable
+\fBFETCHMAIL_INCLUDE_DEFAULT_X509_CA_CERTS\fP to a non-empty value.
+.TP
+.B \-\-sslcommonname <common name>
+(Keyword: sslcommonname; since v6.3.9)
+.br
+Use of this option is discouraged. Before using it, contact the
+administrator of your upstream server and ask for a proper SSL
+certificate to be used. If that cannot be attained, this option can be
+used to specify the name (CommonName) that fetchmail expects on the
+server certificate. A correctly configured server will have this set to
+the hostname by which it is reached, and by default fetchmail will
+expect as much. Use this option when the CommonName is set to some other
+value, to avoid the "Server CommonName mismatch" warning, and only if
+the upstream server can't be made to use proper certificates.
.TP
.B \-\-sslfingerprint <fingerprint>
(Keyword: sslfingerprint)
+.br
Specify the fingerprint of the server key (an MD5 hash of the key) in
hexadecimal notation with colons separating groups of two digits. The letter
hex digits must be in upper case. This is the default format OpenSSL uses,
and the one fetchmail uses to report the fingerprint when an SSL connection
is established. When this is specified, fetchmail will compare the server key
fingerprint with the given one, and the connection will fail if they do not
-match. This can be used to prevent man-in-the-middle attacks.
+match regardless of the \fBsslcertck\fP setting. The connection will
+also fail if fetchmail cannot obtain an SSL certificate from the server.
+This can be used to prevent man-in-the-middle attacks, but the finger
+print from the server needs to be obtained or verified over a secure
+channel, and certainly not over the same Internet connection that
+fetchmail would use.
+.IP
+Using this option will prevent printing certificate verification errors
+as long as \-\-sslcertck is unset.
.IP
To obtain the fingerprint of a certificate stored in the file cert.pem,
try:
.sp
.nf
- openssl x509 -in cert.pem -noout -fingerprint
+ openssl x509 \-in cert.pem \-noout \-md5 \-fingerprint
.fi
.sp
For details, see
.TP
.B \-S <hosts> | \-\-smtphost <hosts>
(Keyword: smtp[host])
+.br
Specify a hunt list of hosts to forward mail to (one or more
hostnames, comma-separated). Hosts are tried in list order; the first
-one that is up becomes the forwarding target for the current run.
-The default depends on the authentication methods and protocols used on
-the active servers. If this option is not specified, 'localhost' is used
-as a default. Each hostname may have a port number following the host
-name. The port number is separated from the host name by a slash; the
-default port is 25 (or "smtp" under IPv6). If you specify an absolute
-path name (beginning with a /), it will be interpreted as the name of a
-UNIX socket accepting LMTP connections (such as is supported by the
-Cyrus IMAP daemon)
+one that is up becomes the forwarding target for the current run. If
+this option is not specified, 'localhost' is used as the default.
+Each hostname may have a port number following the host name. The
+port number is separated from the host name by a slash; the default
+port is "smtp". If you specify an absolute path name (beginning with
+a /), it will be interpreted as the name of a UNIX socket accepting
+LMTP connections (such as is supported by the Cyrus IMAP daemon)
Example:
.sp
.nf
- --smtphost server1,server2/2525,server3,/var/imap/socket/lmtp
+ \-\-smtphost server1,server2/2525,server3,/var/imap/socket/lmtp
.fi
.sp
This option can be used with ODMR, and will make fetchmail a relay
.TP
.B \-\-fetchdomains <hosts>
(Keyword: fetchdomains)
+.br
In ETRN or ODMR mode, this option specifies the list of domains the
server should ship mail for once the connection is turned around. The
-default is the FQDN of the machine running
-.IR fetchmail .
+default is the FQDN of the machine running \fBfetchmail\fP.
.TP
.B \-D <domain> | \-\-smtpaddress <domain>
-(Keyword: smtpaddress) Specify the domain to be appended to addresses
-in RCPT TO lines shipped to SMTP. The name of the SMTP server (as
-specified by --smtphost, which see) is used when this is not specified.
+(Keyword: smtpaddress)
+.br
+Specify the domain to be appended to addresses
+in RCPT TO lines shipped to SMTP. When this is not specified, the name
+of the SMTP server (as specified by \-\-smtphost) is used for SMTP/LMTP
+and 'localhost' is used for UNIX socket/BSMTP.
.TP
.B \-\-smtpname <user@domain>
(Keyword: smtpname)
+.br
Specify the domain and user to be put in RCPT TO lines shipped to SMTP.
The default user is the current local user.
.TP
.B \-Z <nnn> | \-\-antispam <nnn[, nnn]...>
(Keyword: antispam)
+.br
Specifies the list of numeric SMTP errors that are to be interpreted
-as a spam-block response from the listener. A value of -1 disables
+as a spam-block response from the listener. A value of \-1 disables
this option. For the command-line option, the list values should
be comma-separated.
.TP
.B \-m <command> | \-\-mda <command>
-(Keyword: mda) You can force mail to be passed to an MDA directly
-(rather than forwarded to port 25) with the --mda or -m option. To
-avoid losing mail, use this option only with MDAs like maildrop, procmail or
-sendmail that return a nonzero status on disk-full and other
-resource-exhaustion errors; the nonzero status tells fetchmail that
-delivery failed and prevents the message from being deleted off the
-server. If \fIfetchmail\fR is running as root, it sets its user id to
-that of the target user while delivering mail through an MDA. Some
-possible MDAs are "/usr/sbin/sendmail -i -f %F %T", "/usr/bin/deliver"
-and "/usr/bin/procmail -d %T" (but the latter is usually redundant as
-it's what SMTP listeners normally forward to). Local delivery
+(Keyword: mda)
+.br
+This option lets \fBfetchmail\fP use a Message or Local Delivery Agent
+(MDA or LDA) directly, rather than forward via SMTP or LMTP.
+
+To avoid losing mail, use this option only with MDAs like maildrop or
+MTAs like sendmail that exit with a nonzero status on disk-full and other
+delivery errors; the nonzero status tells fetchmail that delivery failed
+and prevents the message from being deleted on the server.
+
+If \fBfetchmail\fP is running as root, it sets its user id while
+delivering mail through an MDA as follows: First, the FETCHMAILUSER,
+LOGNAME, and USER environment variables are checked in this order. The
+value of the first variable from his list that is defined (even if it is
+empty!) is looked up in the system user database. If none of the
+variables is defined, fetchmail will use the real user id it was started
+with. If one of the variables was defined, but the user stated there
+isn't found, fetchmail continues running as root, without checking
+remaining variables on the list. Practically, this means that if you
+run fetchmail as root (not recommended), it is most useful to define the
+FETCHMAILUSER environment variable to set the user that the MDA should
+run as. Some MDAs (such as maildrop) are designed to be setuid root and
+setuid to the recipient's user id, so you don't lose functionality this
+way even when running fetchmail as unprivileged user. Check the MDA's
+manual for details.
+
+Some possible MDAs are "/usr/sbin/sendmail \-i \-f %F \-\- %T"
+(\fBNote:\fP
+some several older or vendor sendmail versions mistake \-\- for an
+address, rather than an indicator to mark the end of the option arguments),
+"/usr/bin/deliver" and "/usr/bin/maildrop \-d %T". Local delivery
addresses will be inserted into the MDA command wherever you place a
%T; the mail message's From address will be inserted where you place
-an %F. \fBDO NOT ENCLOSE THE %F OR %T STRING IN SINGLE QUOTES!\fR For
-both %T and %F, fetchmail encloses the addresses in single quotes ('),
-after removing any single quotes they may contain, before the MDA
-command is passed to the shell. Do \fINOT\fR use an MDA invocation
-like "sendmail -i -t" that dispatches on the contents of To/Cc/Bcc, it
-will create mail loops and bring the just wrath of many postmasters
-down upon your head. Also, do \fInot\fR try to combine multidrop
-mode with an MDA such as procmail that can only accept one address;
-you will lose mail.
+an %F.
+
+\fBDo NOT enclose the %F or %T string in single quotes!\fP
+For both %T and %F, fetchmail encloses the addresses in single quotes
+('), after removing any single quotes they may contain, before the MDA
+command is passed to the shell.
+
+\fBDo NOT use an MDA invocation that dispatches on the contents of
+To/Cc/Bcc,\fP like "sendmail \-i \-t" or "qmail-inject", it will create
+mail loops and bring the just wrath of many postmasters down upon your
+head. This is one of the most frequent configuration errors!
+
+Also, do \fInot\fP try to combine multidrop mode with an MDA such
+as maildrop that can only accept one address, unless your upstream
+stores one copy of the message per recipient and transports the envelope
+recipient in a header; you will lose mail.
+
+The well-known
+.BR procmail (1)
+package is very hard to configure properly, it has a very nasty "fall
+through to the next rule" behavior on delivery errors (even temporary
+ones, such as out of disk space if another user's mail daemon copies the
+mailbox around to purge old messages), so your mail will end up in the
+wrong mailbox sooner or later. The proper procmail configuration is
+outside the scope of this document. Using
+.BR maildrop (1)
+is usually much easier, and many users find the filter syntax used by
+maildrop easier to understand.
+
+Finally, we strongly advise that you do \fBnot\fP use qmail-inject. The
+command line interface is non-standard without providing benefits for
+typical use, and fetchmail makes no attempts to accommodate
+qmail-inject's deviations from the standard. Some of qmail-inject's
+command-line and environment options are actually dangerous and can
+cause broken threads, non-detected duplicate messages and forwarding
+loops.
+
.TP
.B \-\-lmtp
(Keyword: lmtp)
+.br
Cause delivery via LMTP (Local Mail Transfer Protocol). A service
-host and port \fBmust\fR be explicitly specified on each host in the
+host and port \fBmust\fP be explicitly specified on each host in the
smtphost hunt list (see above) if this option is selected; the default
port 25 will (in accordance with RFC 2033) not be accepted.
.TP
.B \-\-bsmtp <filename>
-(keyword: bsmtp)
+(Keyword: bsmtp)
+.br
Append fetched mail to a BSMTP file. This simply contains the SMTP
commands that would normally be generated by fetchmail when passing
-mail to an SMTP listener daemon. An argument of '-' causes the mail
-to be written to standard output. Note that fetchmail's
-reconstruction of MAIL FROM and RCPT TO lines is not guaranteed
-correct; the caveats discussed under THE USE AND ABUSE OF MULTIDROP
-MAILBOXES below apply.
+mail to an SMTP listener daemon.
+
+An argument of '\-' causes the SMTP batch to be written to standard
+output, which is of limited use: this only makes sense for debugging,
+because fetchmail's regular output is interspersed on the same channel,
+so this isn't suitable for mail delivery. This special mode may be
+removed in a later release.
+
+Note that fetchmail's reconstruction of MAIL FROM and RCPT TO lines is
+not guaranteed correct; the caveats discussed under THE USE AND ABUSE OF
+MULTIDROP MAILBOXES below apply. This mode has precedence before
+\-\-mda and SMTP/LMTP.
+.TP
+.B \-\-bad\-header {reject|accept}
+(Keyword: bad\-header; since v6.3.15)
+.br
+Specify how fetchmail is supposed to treat messages with bad headers,
+i. e. headers with bad syntax. Traditionally, fetchmail has rejected such
+messages, but some distributors modified fetchmail to accept them. You can now
+configure fetchmail's behaviour per server.
+
.SS Resource Limit Control Options
.TP
.B \-l <maxbytes> | \-\-limit <maxbytes>
-(Keyword: limit) Takes a maximum octet size argument. Messages larger
-than this size will not be fetched and will be left on the server (in
-foreground sessions, the progress messages will note that they are
-"oversized"). If the fetch protocol permits (in particular, under
-IMAP or POP3 without the fetchall option) the message will not be
-marked seen.
+(Keyword: limit)
+.br
+Takes a maximum octet size argument, where 0 is the
+default and also the special value designating "no limit".
+If nonzero, messages larger than this size will not be fetched and will
+be left on the server (in foreground sessions, the progress messages
+will note that they are "oversized"). If the fetch protocol permits (in
+particular, under IMAP or POP3 without the fetchall option) the message
+will not be marked seen.
.sp
-An explicit --limit of 0 overrides any limits set in your
+An explicit \-\-limit of 0 overrides any limits set in your
run control file. This option is intended for those needing to
strictly control fetch time due to expensive and variable phone rates.
.sp
-Combined with --limitflush, it can be used to delete oversized
+Combined with \-\-limitflush, it can be used to delete oversized
messages waiting on a server. In daemon mode, oversize notifications
-are mailed to the calling user (see the --warnings option). This
+are mailed to the calling user (see the \-\-warnings option). This
option does not work with ETRN or ODMR.
.TP
.B \-w <interval> | \-\-warnings <interval>
(Keyword: warnings)
-Takes an interval in seconds. When you call
-.I fetchmail
+.br
+Takes an interval in seconds. When you call \fBfetchmail\fP
with a 'limit' option in daemon mode, this controls the interval at
which warnings about oversized messages are mailed to the calling user
(or the user specified by the 'postmaster' option). One such
notification is always mailed at the end of the the first poll that
-the oversized message is detected. Thereafter, renotification is
+the oversized message is detected. Thereafter, re-notification is
suppressed until after the warning interval elapses (it will take
place at the end of the first following poll).
.TP
.B \-b <count> | \-\-batchlimit <count>
(Keyword: batchlimit)
+.br
Specify the maximum number of messages that will be shipped to an SMTP
listener before the connection is deliberately torn down and rebuilt
-(defaults to 0, meaning no limit). An explicit --batchlimit of 0
+(defaults to 0, meaning no limit). An explicit \-\-batchlimit of 0
overrides any limits set in your run control file. While
-\fBsendmail\fR(8) normally initiates delivery of a message immediately
+\fBsendmail\fP(8) normally initiates delivery of a message immediately
after receiving the message terminator, some SMTP listeners are not so
-prompt. MTAs like \fIsmail\fR(8) may wait till the
+prompt. MTAs like \fBsmail\fP(8) may wait till the
delivery socket is shut down to deliver. This may produce annoying
-delays when \fIfetchmail\fR is processing very large batches. Setting
+delays when \fBfetchmail\fP is processing very large batches. Setting
the batch limit to some nonzero size will prevent these delays. This
option does not work with ETRN or ODMR.
.TP
.B \-B <number> | \-\-fetchlimit <number>
(Keyword: fetchlimit)
+.br
Limit the number of messages accepted from a given server in a single
-poll. By default there is no limit. An explicit --fetchlimit of 0
+poll. By default there is no limit. An explicit \-\-fetchlimit of 0
overrides any limits set in your run control file.
This option does not work with ETRN or ODMR.
.TP
.B \-\-fetchsizelimit <number>
(Keyword: fetchsizelimit)
+.br
Limit the number of sizes of messages accepted from a given server in
a single transaction. This option is useful in reducing the delay in
downloading the first mail when there are too many mails in the
.TP
.B \-\-fastuidl <number>
(Keyword: fastuidl)
+.br
Do a binary instead of linear search for the first unseen UID. Binary
search avoids downloading the UIDs of all mails. This saves time
(especially in daemon mode) where downloading the same set of UIDs in
once followed by binary searches in 'n-1' polls if 'n' is greater than
1; binary search is always used if 'n' is 1; linear search is always
used if 'n' is 0. In non-daemon mode, binary search is used if 'n' is
-1; otherwise linear search is used.
+1; otherwise linear search is used. The default value of 'n' is 4.
This option works with POP3 only.
.TP
.B \-e <count> | \-\-expunge <count>
-(keyword: expunge)
+(Keyword: expunge)
+.br
Arrange for deletions to be made final after a given number of
messages. Under POP2 or POP3, fetchmail cannot make deletions final
without sending QUIT and ending the session -- with this option on,
fetchmail will break a long mail retrieval session into multiple
sub-sessions, sending QUIT after each sub-session. This is a good
-defense against line drops on POP3 servers that do not do the
-equivalent of a QUIT on hangup. Under IMAP,
-.I fetchmail
-normally issues an EXPUNGE command after each deletion in order to
-force the deletion to be done immediately. This is safest when your
-connection to the server is flaky and expensive, as it avoids
+defense against line drops on POP3 servers. Under IMAP,
+\fBfetchmail\fP normally issues an EXPUNGE command after each deletion
+in order to force the deletion to be done immediately. This is safest
+when your connection to the server is flaky and expensive, as it avoids
resending duplicate mail after a line hit. However, on large
mailboxes the overhead of re-indexing after every message can slam the
server pretty hard, so if your connection is reliable it is good to do
of a few seconds after each quit, so fetchmail may not be able to get
back in immediately after an expunge -- you may see "lock busy" errors
if this happens. If you specify this option to an integer N,
-it tells
-.I fetchmail
-to only issue expunges on every Nth delete. An argument of zero
-suppresses expunges entirely (so no expunges at all will be done until
-the end of run). This option does not work with ETRN or ODMR.
+it tells \fBfetchmail\fP to only issue expunges on every Nth delete. An
+argument of zero suppresses expunges entirely (so no expunges at all
+will be done until the end of run). This option does not work with ETRN
+or ODMR.
+
.SS Authentication Options
.TP
.B \-u <name> | \-\-user <name> | \-\-username <name>
(Keyword: user[name])
+.br
Specifies the user identification to be used when logging in to the mailserver.
The appropriate user identification is both server and user-dependent.
The default is your login name on the client machine that is running
-.IR fetchmail .
+\fBfetchmail\fP.
See USER AUTHENTICATION below for a complete description.
.TP
.B \-I <specification> | \-\-interface <specification>
(Keyword: interface)
+.br
Require that a specific interface device be up and have a specific local
or remote IPv4 (IPv6 is not supported by this option yet) address (or
-range) before polling. Frequently \fIfetchmail\fP
+range) before polling. Frequently \fBfetchmail\fP
is used over a transient point-to-point TCP/IP link established directly
to a mailserver via SLIP or PPP. That is a relatively secure channel.
But when other TCP/IP routes to the mailserver exist (e.g. when the link
is connected to an alternate ISP), your username and password may be
vulnerable to snooping (especially when daemon mode automatically polls
for mail, shipping a clear password over the net at predictable
-intervals). The --interface option may be used to prevent this. When
+intervals). The \-\-interface option may be used to prevent this. When
the specified link is not up or is not connected to a matching IP
address, polling will be skipped. The format is:
.sp
The field after the second slash is a mask which specifies a range of
IP addresses to accept. If no mask is present 255.255.255.255 is
assumed (i.e. an exact match). This option is currently only supported
-under Linux and FreeBSD. Please see the
-.B monitor
-section for below for FreeBSD specific information.
+under Linux and FreeBSD. Please see the \fBmonitor\fP section for below
+for FreeBSD specific information.
.sp
Note that this option may be removed from a future fetchmail version.
.TP
.B \-M <interface> | \-\-monitor <interface>
(Keyword: monitor)
+.br
Daemon mode can cause transient links which are automatically taken down
after a period of inactivity (e.g. PPP links) to remain up
indefinitely. This option identifies a system TCP/IP interface to be
skipped. However, when fetchmail is woken up by a signal, the
monitor check is skipped and the poll goes through unconditionally.
This option is currently only supported under Linux and FreeBSD.
-For the
-.B monitor
-and
-.B interface
-options to work for non root users under FreeBSD, the fetchmail binary
-must be installed SGID kmem. This would be a security hole, but
-fetchmail runs with the effective GID set to that of the kmem group
-.I only
-when interface data is being collected.
+For the \fBmonitor\fP and \fBinterface\fP options to work for non root
+users under FreeBSD, the fetchmail binary must be installed SGID kmem.
+This would be a security hole, but fetchmail runs with the effective GID
+set to that of the kmem group \fIonly\fP when interface data is being
+collected.
.sp
Note that this option may be removed from a future fetchmail version.
.TP
.B \-\-auth <type>
(Keyword: auth[enticate])
+.br
This option permits you to specify an authentication type (see USER
-AUTHENTICATION below for details). The possible values are \fBany\fR,
-\&\fBpassword\fR, \fBkerberos_v5\fR, \fBkerberos\fR (or, for
-excruciating exactness, \fBkerberos_v4\fR), \fBgssapi\fR,
-\fBcram-md5\fR, \fBotp\fR, \fBntlm\fR, \fBmsn\fR (only for POP3) and
-\fBssh\fR. When \fBany\fR (the default) is specified, fetchmail tries
-first methods that don't require a password (GSSAPI, KERBEROS\ IV,
+AUTHENTICATION below for details). The possible values are \fBany\fP,
+\&\fBpassword\fP, \fBkerberos_v5\fP, \fBkerberos\fP (or, for
+excruciating exactness, \fBkerberos_v4\fP), \fBgssapi\fP,
+\fBcram\-md5\fP, \fBotp\fP, \fBntlm\fP, \fBmsn\fP (only for POP3),
+\fBexternal\fP (only IMAP) and \fBssh\fP.
+When \fBany\fP (the default) is specified, fetchmail tries
+first methods that don't require a password (EXTERNAL, GSSAPI, KERBEROS\ IV,
KERBEROS\ 5); then it looks for methods that mask your password
-(CRAM-MD5, X-OTP - note that NTLM and MSN are not autoprobed for POP3
-and MSN is only supported for POP3); and only if the server doesn't
+(CRAM-MD5, NTLM, X\-OTP - note that MSN is only supported for POP3, but not
+autoprobed); and only if the server doesn't
support any of those will it ship your password en clair. Other values
may be used to force various authentication methods
-(\fBssh\fR suppresses authentication and is thus good for IMAP PREAUTH).
-Any value other than \fBpassword\fR, \fBcram-md5\fR, \fBntlm\fR,
-\&\fBmsn\fR or \fBotp\fR suppresses fetchmail's normal inquiry for a
-password. Specify \fBssh\fR when you are using an end-to-end secure
-connection such as an ssh tunnel; specify \fBgssapi\fR or
-\&\fBkerberos_v4\fR if you are using a protocol variant that employs
+(\fBssh\fP suppresses authentication and is thus useful for IMAP PREAUTH).
+(\fBexternal\fP suppresses authentication and is thus useful for IMAP EXTERNAL).
+Any value other than \fBpassword\fP, \fBcram\-md5\fP, \fBntlm\fP,
+\&\fBmsn\fP or \fBotp\fP suppresses fetchmail's normal inquiry for a
+password. Specify \fBssh\fP when you are using an end-to-end secure
+connection such as an ssh tunnel; specify \fBexternal\fP when you use
+TLS with client authentication and specify \fBgssapi\fP or
+\&\fBkerberos_v4\fP if you are using a protocol variant that employs
GSSAPI or K4. Choosing KPOP protocol automatically selects Kerberos
-authentication. This option does not work with ETRN.
+authentication. This option does not work with ETRN. GSSAPI service names are
+in line with RFC-2743 and IANA registrations, see
+.URL http://www.iana.org/assignments/gssapi-service-names/ "Generic Security Service Application Program Interface (GSSAPI)/Kerberos/Simple Authentication and Security Layer (SASL) Service Names" .
.SS Miscellaneous Options
.TP
.B \-f <pathname> | \-\-fetchmailrc <pathname>
-Specify a non-default name for the
-.I ~/.fetchmailrc
+Specify a non-default name for the \fI~/.fetchmailrc\fP
run control file. The pathname argument must be either "-" (a single
dash, meaning to read the configuration from standard input) or a
-filename. Unless the --version option is also on, a named file
-argument must have permissions no more open than 0600 (u=rw,g=,o=) or
+filename. Unless the \-\-version option is also on, a named file
+argument must have permissions no more open than 0700 (u=rwx,g=,o=) or
else be /dev/null.
.TP
.B \-i <pathname> | \-\-idfile <pathname>
(Keyword: idfile)
-Specify an alternate name for the .fetchids file used to save POP3
-UIDs.
+.br
+Specify an alternate name for the .fetchids file used to save message
+UIDs. NOTE: since fetchmail 6.3.0, write access to the directory
+containing the idfile is required, as fetchmail writes a temporary file
+and renames it into the place of the real idfile only if the temporary
+file has been written successfully. This avoids the truncation of
+idfiles when running out of disk space.
+.TP
+.B \--pidfile <pathname>
+(Keyword: pidfile; since fetchmail v6.3.4)
+.br
+Override the default location of the PID file. Default: see
+"ENVIRONMENT" below.
.TP
.B \-n | \-\-norewrite
(Keyword: no rewrite)
-Normally,
-.I fetchmail
-edits RFC-822 address headers (To, From, Cc, Bcc, and Reply-To) in
-fetched mail so that any mail IDs local to the server are expanded to
-full addresses (@ and the mailserver hostname are appended). This enables
-replies on the client to get addressed correctly (otherwise your
-mailer might think they should be addressed to local users on the
-client machine!). This option disables the rewrite. (This option is
-provided to pacify people who are paranoid about having an MTA edit
-mail headers and want to know they can prevent it, but it is generally
-not a good idea to actually turn off rewrite.)
+.br
+Normally, \fBfetchmail\fP edits RFC-822 address headers (To, From, Cc,
+Bcc, and Reply\-To) in fetched mail so that any mail IDs local to the
+server are expanded to full addresses (@ and the mailserver hostname are
+appended). This enables replies on the client to get addressed
+correctly (otherwise your mailer might think they should be addressed to
+local users on the client machine!). This option disables the rewrite.
+(This option is provided to pacify people who are paranoid about having
+an MTA edit mail headers and want to know they can prevent it, but it is
+generally not a good idea to actually turn off rewrite.)
When using ETRN or ODMR, the rewrite option is ineffective.
.TP
.B \-E <line> | \-\-envelope <line>
.br
In the configuration file, an enhanced syntax is used:
.br
-.B envelope [<count>] <line>
+\fBenvelope [<count>] <line>\fP
.sp
-This option changes the header
-.I fetchmail
-assumes will carry a copy of the mail's envelope address. Normally
-this is 'X-Envelope-To' but as this header is not standard, practice
-varies. See the discussion of multidrop address handling below. As a
-special case, 'envelope "Received"' enables parsing of sendmail-style
-Received lines. This is the default, and it should not be necessary
-unless you have globally disabled Received parsing with 'no envelope'
-in the \fI.fetchmailrc\fR file.
+This option changes the header \fBfetchmail\fP assumes will carry a copy
+of the mail's envelope address. Normally this is 'X\-Envelope\-To'.
+Other typically found headers to carry envelope information are
+\&'X\-Original\-To' and 'Delivered\-To'. Now, since these headers are
+not standardized, practice varies. See the discussion of multidrop
+address handling below. As a special case, 'envelope "Received"'
+enables parsing of sendmail-style Received lines. This is the default,
+but discouraged because it is not fully reliable.
+
+Note that fetchmail expects the Received-line to be in a specific
+format: It must contain "by \fIhost\fP for \fIaddress\fP", where
+\fIhost\fP must match one of the mailserver names that fetchmail
+recognizes for the account in question.
.sp
The optional count argument (only available in the configuration file)
determines how many header lines of this kind are skipped. A count of 1
.TP
.B \-Q <prefix> | \-\-qvirtual <prefix>
(Keyword: qvirtual; Multidrop only)
+.br
The string prefix assigned to this option will be removed from the user
-name found in the header specified with the \fIenvelope\fR option
-(\fIbefore\fR doing multidrop name mapping or localdomain checking,
+name found in the header specified with the \fIenvelope\fP option
+(\fIbefore\fP doing multidrop name mapping or localdomain checking,
if either is applicable). This option is useful if you are using
-.I fetchmail
-to collect the mail for an entire domain and your ISP (or your mail
-redirection provider) is using qmail.
-One of the basic features of qmail is the
-.sp
-\&'Delivered-To:'
-.sp
+\fBfetchmail\fP to collect the mail for an entire domain and your ISP
+(or your mail redirection provider) is using qmail.
+One of the basic features of qmail is the \fIDelivered\-To:\fP
message header. Whenever qmail delivers a message to a local mailbox
it puts the username and hostname of the envelope recipient on this
line. The major reason for this is to prevent mail loops. To set up
add a prefix to all mail addresses for this site. This results in mail
.\" The \&@\& tries to stop HTML converters from making a mailto URL here.
sent to 'username\&@\&userhost.userdom.dom.com' having a
-\&'Delivered-To:' line of the form:
-.sp
-Delivered-To: mbox-userstr-username\&@\&userhost.userdom.dom.com
-.sp
-The ISP can make the 'mbox-userstr-' prefix anything they choose
+\fIDelivered\-To:\fR line of the form:
+.IP
+Delivered\-To: mbox\-userstr\-username\&@\&userhost.example.com
+.PP
+The ISP can make the 'mbox\-userstr\-' prefix anything they choose
but a string matching the user host name is likely.
-By using the option 'envelope Delivered-To:' you can make fetchmail reliably
+By using the option 'envelope Delivered\-To:' you can make fetchmail reliably
identify the original envelope recipient, but you have to strip the
-\&'mbox-userstr-' prefix to deliver to the correct user.
+\&'mbox\-userstr\-' prefix to deliver to the correct user.
This is what this option is for.
.TP
-.B --configdump
-Parse the
-.I ~/.fetchmailrc
-file, interpret any command-line options specified, and dump a
-configuration report to standard output. The configuration report is
-a data structure assignment in the language Python. This option
-is meant to be used with an interactive
-.I ~/.fetchmailrc
-editor like
-.IR fetchmailconf ,
-written in Python.
+.B \-\-configdump
+Parse the \fI~/.fetchmailrc\fP file, interpret any command-line options
+specified, and dump a configuration report to standard output. The
+configuration report is a data structure assignment in the language
+Python. This option is meant to be used with an interactive
+\fI~/.fetchmailrc\fP editor like \fBfetchmailconf\fP, written in Python.
+
.SS Removed Options
.TP
-.B -T | --netsec
+.B \-T | \-\-netsec
Removed before version 6.3.0, the required underlying inet6_apps library
had been discontinued and is no longer available.
.SH USER AUTHENTICATION AND ENCRYPTION
All modes except ETRN require authentication of the client to the server.
-Normal user authentication in
-.I fetchmail
-is very much like the authentication mechanism of
-.IR ftp (1).
+Normal user authentication in \fBfetchmail\fP is very much like the
+authentication mechanism of
+.BR ftp (1).
The correct user-id and password depend upon the underlying security
system at the mailserver.
.PP
If the mailserver is a Unix machine on which you have an ordinary user
account, your regular login name and password are used with
-.IR fetchmail .
+.BR fetchmail .
If you use the same login name on both the server and the client machines,
you needn't worry about specifying a user-id with the
.B \-u
-option \-\- the default behavior is to use your login name on the
+option -- the default behavior is to use your login name on the
client machine as the user-id on the server machine. If you use a
different login name on the server machine, specify that login name
with the
.B \-u
option. e.g. if your login name is 'jsmith' on a machine named 'mailgrunt',
-you would start
-.I fetchmail
-as follows:
+you would start \fBfetchmail\fP as follows:
.IP
-fetchmail -u jsmith mailgrunt
-.PP
-The default behavior of
-.I fetchmail
-is to prompt you for your mailserver password before the connection is
-established. This is the safest way to use
-.I fetchmail
-and ensures that your password will not be compromised. You may also specify
-your password in your
-.I ~/.fetchmailrc
-file. This is convenient when using
-.I fetchmail
-in daemon mode or with scripts.
+fetchmail \-u jsmith mailgrunt
+.PP
+The default behavior of \fBfetchmail\fP is to prompt you for your
+mailserver password before the connection is established. This is the
+safest way to use \fBfetchmail\fP and ensures that your password will
+not be compromised. You may also specify your password in your
+\fI~/.fetchmailrc\fP file. This is convenient when using
+\fBfetchmail\fP in daemon mode or with scripts.
+
.SS Using netrc files
.PP
-If you do not specify a password, and
-.I fetchmail
-cannot extract one from your
-.I ~/.fetchmailrc
-file, it will look for a
-.I ~/.netrc
+If you do not specify a password, and \fBfetchmail\fP cannot extract one
+from your \fI~/.fetchmailrc\fP file, it will look for a \fI~/.netrc\fP
file in your home directory before requesting one interactively; if an
entry matching the mailserver is found in that file, the password will
be used. Fetchmail first looks for a match on poll name; if it finds none,
it checks for a match on via name. See the
-.IR ftp (1)
-man page for details of the syntax of the
-.I ~/.netrc
+.BR ftp (1)
+man page for details of the syntax of the \fI~/.netrc\fP
file. To show a practical example, a .netrc might look like
this:
.IP
password are usually assigned by the server administrator when you apply for
a mailbox on the server. Contact your server administrator if you don't know
the correct user-id and password for your mailbox account.
-.SS POP3 variants
+.SH POP3 VARIANTS
.PP
Early versions of POP3 (RFC1081, RFC1225) supported a crude form of
-independent authentication using the
-.I rhosts
-file on the mailserver side. Under this RPOP variant, a fixed
-per-user ID equivalent to a password was sent in clear over a link to
-a reserved port, with the command RPOP rather than PASS to alert the
-server that it should do special checking. RPOP is supported
-by
-.I fetchmail
+independent authentication using the \fI.rhosts\fP file on the
+mailserver side. Under this RPOP variant, a fixed per-user ID
+equivalent to a password was sent in clear over a link to a reserved
+port, with the command RPOP rather than PASS to alert the server that it
+should do special checking. RPOP is supported by \fBfetchmail\fP
(you can specify 'protocol RPOP' to have the program send 'RPOP'
-rather than 'PASS') but its use is strongly discouraged. This
+rather than 'PASS') but its use is strongly discouraged, and support
+will be removed from a future fetchmail version. This
facility was vulnerable to spoofing and was withdrawn in RFC1460.
.PP
RFC1460 introduced APOP authentication. In this variant of POP3,
-you register an APOP password on your server host (the program
-to do this with on the server is probably called \fIpopauth\fR(8)). You
-put the same password in your
-.I ~/.fetchmailrc
-file. Each time
-.I fetchmail
-logs in, it sends a cryptographically secure hash of your password and
-the server greeting time to the server, which can verify it by
-checking its authorization database.
-.SS Alternate authentication forms
-.PP
-If your \fIfetchmail\fR was built with Kerberos support and you specify
-Kerberos authentication (either with --auth or the \fI.fetchmailrc\fR
-option \fBauthenticate kerberos_v4\fR) it will try to get a Kerberos
+you register an APOP password on your server host (on some servers, the
+program to do this is called \fBpopauth\fP(8)). You put the same
+password in your \fI~/.fetchmailrc\fP file. Each time \fBfetchmail\fP
+logs in, it sends an MD5 hash of your password and the server greeting
+time to the server, which can verify it by checking its authorization
+database.
+
+\fBNote that APOP is no longer considered resistant against
+man-in-the-middle attacks.\fP
+.SS RETR or TOP
+\fBfetchmail\fP makes some efforts to make the server believe messages
+had not been retrieved, by using the TOP command with a large number of
+lines when possible. TOP is a command that retrieves the full header
+and a \fBfetchmail\fP-specified amount of body lines. It is optional and
+therefore not implemented by all servers, and some are known to
+implement it improperly. On many servers however, the RETR command which
+retrieves the full message with header and body, sets the "seen" flag
+(for instance, in a web interface), whereas the TOP command does not do
+that.
+.PP
+\fBfetchmail\fP will always use the RETR command if "fetchall" is set.
+\fBfetchmail\fP will also use the RETR command if "keep" is set and
+"uidl" is unset. Finally, \fBfetchmail\fP will use the RETR command on
+Maillennium POP3/PROXY servers (used by Comcast) to avoid a deliberate
+TOP misinterpretation in this server that causes message corruption.
+.PP
+In all other cases, \fBfetchmail\fP will use the TOP command. This
+implies that in "keep" setups, "uidl" must be set if "TOP" is desired.
+.PP
+\fBNote\fP that this description is true for the current version of
+fetchmail, but the behavior may change in future versions. In
+particular, fetchmail may prefer the RETR command because the TOP
+command causes much grief on some servers and is only optional.
+.SH ALTERNATE AUTHENTICATION FORMS
+.PP
+If your \fBfetchmail\fP was built with Kerberos support and you specify
+Kerberos authentication (either with \-\-auth or the \fI.fetchmailrc\fP
+option \fBauthenticate kerberos_v4\fP) it will try to get a Kerberos
ticket from the mailserver at the start of each query. Note: if
either the pollname or via name is 'hesiod', fetchmail will try to use
Hesiod to look up the mailserver.
.PP
-If you use POP3 or IMAP with GSSAPI authentication, \fIfetchmail\fR will
-expect the server to have RFC1731- or RFC1734-conformant GSSAPI
+If you use POP3 or IMAP with GSSAPI authentication, \fBfetchmail\fP will
+expect the server to have RFC1731- or RFC1734-conforming GSSAPI
capability, and will use it. Currently this has only been tested over
Kerberos V, so you're expected to already have a ticket-granting
ticket. You may pass a username different from your principal name
-using the standard \fB--user\fR command or by the \fI.fetchmailrc\fR
-option \fBuser\fR.
+using the standard \fB\-\-user\fP command or by the \fI.fetchmailrc\fP
+option \fBuser\fP.
.PP
If your IMAP daemon returns the PREAUTH response in its greeting line,
fetchmail will notice this and skip the normal authentication step.
This can be useful, e.g. if you start imapd explicitly using ssh.
In this case you can declare the authentication value 'ssh' on that
-site entry to stop \fI.fetchmail\fR from asking you for a password
+site entry to stop \fI.fetchmail\fP from asking you for a password
+when it starts up.
+.PP
+If you use client authentication with \fITLS1\fP and your IMAP daemon
+returns the \fIAUTH=EXTERNAL\fP response, fetchmail will notice this
+and will use the authentication shortcut and will not send the
+passphrase. In this case you can declare the authentication value 'external'
+ on that site to stop \fBfetchmail\fP from asking you for a password
when it starts up.
.PP
If you are using POP3, and the server issues a one-time-password
-challenge conforming to RFC1938, \fIfetchmail\fR will use your
+challenge conforming to RFC1938, \fBfetchmail\fP will use your
password as a pass phrase to generate the required response. This
avoids sending secrets over the net unencrypted.
.PP
-Compuserve's RPA authentication (similar to APOP) is supported. If you
-compile in the support, \fIfetchmail\fR will try to perform an RPA pass-phrase
+Compuserve's RPA authentication is supported. If you
+compile in the support, \fBfetchmail\fP will try to perform an RPA pass-phrase
authentication instead of sending over the password en clair if it
detects "@compuserve.com" in the hostname.
.PP
If you are using IMAP, Microsoft's NTLM authentication (used by Microsoft
-Exchange) is supported. If you compile in the support, \fIfetchmail\fR
+Exchange) is supported. If you compile in the support, \fBfetchmail\fP
will try to perform an NTLM authentication (instead of sending over the
password en clair) whenever the server returns AUTH=NTLM in its
capability response. Specify a user option value that looks like
\&'user@domain': the part to the left of the @ will be passed as the
username and the part to the right as the NTLM domain.
-.SS Secure Socket Layers (SSL)
-.PP
-You can access SSL encrypted services by specifying the --ssl option.
-You can also do this using the "ssl" server option in the .fetchmailrc
-file. With SSL encryption enabled, queries are initiated over a connection
-after negotiating an SSL session. Some services, such as POP3 and IMAP,
-have different well known ports defined for the SSL encrypted services.
-The encrypted ports will be selected automatically when SSL is enabled and
-no explicit port is specified.
-.PP
-When connecting to an SSL encrypted server, the server presents a certificate
-to the client for validation. The certificate is checked to verify that
-the common name in the certificate matches the name of the server being
-contacted and that the effective and expiration dates in the certificate
-indicate that it is currently valid. If any of these checks fail, a warning
-message is printed, but the connection continues. The server certificate
-does not need to be signed by any specific Certifying Authority and may
-be a "self-signed" certificate.
+
+.SS Secure Socket Layers (SSL) and Transport Layer Security (TLS)
+.PP
+Note that fetchmail currently uses the OpenSSL library, which is
+severely underdocumented, so failures may occur just because the
+programmers are not aware of OpenSSL's requirement of the day.
+For instance, since v6.3.16, fetchmail calls
+OpenSSL_add_all_algorithms(), which is necessary to support certificates
+with SHA256 on OpenSSL 0.9.8 -- this information is deeply hidden in the
+documentation and not at all obvious. Please do not hesitate to report
+subtle SSL failures.
+.PP
+You can access SSL encrypted services by specifying the \-\-ssl option.
+You can also do this using the "ssl" user option in the .fetchmailrc
+file. With SSL encryption enabled, queries are initiated over a
+connection after negotiating an SSL session, and the connection fails if
+SSL cannot be negotiated. Some services, such as POP3 and IMAP, have
+different well known ports defined for the SSL encrypted services. The
+encrypted ports will be selected automatically when SSL is enabled and
+no explicit port is specified. The \-\-sslproto 'SSL3' option should be
+used to select the SSLv3 protocol (default if unset: v2 or v3). Also,
+the \-\-sslcertck command line or sslcertck run control file option
+should be used to force strict certificate checking - see below.
+.PP
+If SSL is not configured, fetchmail will usually opportunistically try to use
+STARTTLS. STARTTLS can be enforced by using \-\-sslproto "TLS1". TLS
+connections use the same port as the unencrypted version of the
+protocol and negotiate TLS via special command. The \-\-sslcertck
+command line or sslcertck run control file option should be used to
+force strict certificate checking - see below.
+.PP
+.B \-\-sslcertck is recommended:
+When connecting to an SSL or TLS encrypted server, the
+server presents a certificate to the client for validation. The
+certificate is checked to verify that the common name in the certificate
+matches the name of the server being contacted and that the effective
+and expiration dates in the certificate indicate that it is currently
+valid. If any of these checks fail, a warning message is printed, but
+the connection continues. The server certificate does not need to be
+signed by any specific Certifying Authority and may be a "self-signed"
+certificate. If the \-\-sslcertck command line option or sslcertck run
+control file option is used, fetchmail will instead abort if any of
+these checks fail, because it must assume that there is a
+man-in-the-middle attack in this scenario, hence fetchmail must not
+expose cleartext passwords. Use of the sslcertck or \-\-sslcertck option
+is therefore advised.
.PP
Some SSL encrypted servers may request a client side certificate. A client
side public SSL certificate and private SSL key may be specified. If
.PP
A word of care about the use of SSL: While above mentioned
setup with self-signed server certificates retrieved over the wires
-can protect you from a passive eavesdropper it doesn't help against an
+can protect you from a passive eavesdropper, it doesn't help against an
active attacker. It's clearly an improvement over sending the
-passwords in clear but you should be aware that a man-in-the-middle
-attack is trivially possible (in particular with tools such as dsniff,
-http://www.monkey.org/~dugsong/dsniff/). Use of an ssh tunnel (see
-below for some examples) is preferable if you care seriously about the
-security of your mailbox.
-.SS SMTP AUTH
-.PP
-.B fetchmail
-also supports authentication to the ESMTP server on the client side
-according to RFC 2554. You can specify a name/password pair to be
-used with the keywords 'esmtpname' and 'esmtppassword'; the former
+passwords in clear, but you should be aware that a man-in-the-middle
+attack is trivially possible (in particular with tools such as
+.URL "http://monkey.org/~dugsong/dsniff/" "dsniff" ,
+). Use of strict certificate checking with a certification authority
+recognized by server and client, or perhaps of an SSH tunnel (see below
+for some examples) is preferable if you care seriously about the
+security of your mailbox and passwords.
+
+.SS ESMTP AUTH
+.PP
+\fBfetchmail\fP also supports authentication to the ESMTP server on the
+client side according to RFC 2554. You can specify a name/password pair
+to be used with the keywords 'esmtpname' and 'esmtppassword'; the former
defaults to the username of the calling user.
.SH DAEMON MODE
-The
-.B \-\-daemon <interval>
-or
-.B \-d <interval>
-option runs
-.I fetchmail
-in daemon mode. You must specify a numeric argument which is a
-polling interval in seconds.
-.PP
-In daemon mode,
-.I fetchmail
-puts itself in background and runs forever, querying each specified
-host and then sleeping for the given polling interval.
-.PP
-Simply invoking
+.SS Introducing the daemon mode
+In daemon mode, \fBfetchmail\fP puts itself into the background and runs
+forever, querying each specified host and then sleeping for a given
+polling interval.
+.SS Starting the daemon mode
+There are several ways to make fetchmail work in daemon mode. On the
+command line, \fB\-\-daemon\ <interval>\fP or \fB\-d\ <interval>\fP
+option runs \fBfetchmail\fP in daemon mode. You must specify a numeric
+argument which is a polling interval (time to wait after completing a
+whole poll cycle with the last server and before starting the next poll
+cycle with the first server) in seconds.
+.PP
+Example: simply invoking
.IP
-fetchmail -d 900
+fetchmail \-d 900
.PP
-will, therefore, poll all the hosts described in your
-.I ~/.fetchmailrc
-file (except those explicitly excluded with the 'skip' verb) once
-every fifteen minutes.
+will, therefore, poll all the hosts described in your \fI~/.fetchmailrc\fP
+file (except those explicitly excluded with the 'skip' verb) a bit less
+often than once every 15 minutes (exactly: 15 minutes + time that the
+poll takes).
.PP
-It is possible to set a polling interval
-in your
-.I ~/.fetchmailrc
-file by saying 'set daemon <interval>', where <interval> is an
-integer number of seconds. If you do this, fetchmail will always
-start in daemon mode unless you override it with the command-line
-option --daemon 0 or -d0.
+It is also possible to set a polling interval
+in your \fI~/.fetchmailrc\fP file by saying 'set\ daemon\ <interval>',
+where <interval> is an integer number of seconds. If you do this,
+fetchmail will always start in daemon mode unless you override it with
+the command-line option \-\-daemon 0 or \-d0.
.PP
Only one daemon process is permitted per user; in daemon mode,
-.I fetchmail
-makes a per-user lockfile to guarantee this.
+\fBfetchmail\fP sets up a per-user lockfile to guarantee this.
+(You can however cheat and set the FETCHMAILHOME environment variable to
+overcome this setting, but in that case, it is your responsibility to
+make sure you aren't polling the same server with two processes at the
+same time.)
+.SS Awakening the background daemon
.PP
Normally, calling fetchmail with a daemon in the background sends a
-wake-up signal to the daemon, forcing it to poll mailservers
-immediately. (The wake-up signal is SIGHUP if fetchmail is running as
-root, SIGUSR1 otherwise.) The wake-up action also clears any 'wedged'
-flags indicating that connections have wedged due to failed
+wake-up signal to the daemon and quits without output. The background
+daemon then starts its next poll cycle immediately. The wake-up signal,
+SIGUSR1, can also be sent manually. The wake-up action also clears any
+\&'wedged' flags indicating that connections have wedged due to failed
authentication or multiple timeouts.
+.SS Terminating the background daemon
.PP
The option
.B \-\-quit
will kill a running daemon process instead of waking it up (if there
-is no such process, \fIfetchmail\fP will notify you.
-If the \-\-quit option appears last on the command line, \fIfetchmail\fP
+is no such process, \fBfetchmail\fP will notify you).
+If the \-\-quit option appears last on the command line, \fBfetchmail\fP
will kill the running daemon process and then quit. Otherwise,
-\fIfetchmail\fP will first kill a running daemon process and then
+\fBfetchmail\fP will first kill a running daemon process and then
continue running with the other options.
+.SS Useful options for daemon mode
.PP
The
.B \-L <filename>
or
.B \-\-logfile <filename>
option (keyword: set logfile) is only effective when fetchmail is
-detached. This option allows you to redirect status messages
+detached and in daemon mode. Note that \fBthe logfile must exist
+before\fP fetchmail is run, you can use the
+.BR touch (1)
+command with the filename as its sole argument to create it.
+.br
+This option allows you to redirect status messages
into a specified logfile (follow the option with the logfile name). The
logfile is opened for append, so previous messages aren't deleted. This
-is primarily useful for debugging configurations.
+is primarily useful for debugging configurations. Note that fetchmail
+does not detect if the logfile is rotated, the logfile is only opened
+once when fetchmail starts. You need to restart fetchmail after rotating
+the logfile and before compressing it (if applicable).
.PP
The
.B \-\-syslog
option (keyword: set syslog) allows you to redirect status and error
messages emitted to the
-.IR syslog (3)
+.BR syslog (3)
system daemon if available.
-Messages are logged with an id of \fBfetchmail\fR, the facility \fBLOG_MAIL\fR,
-and priorities \fBLOG_ERR\fR, \fBLOG_ALERT\fR or \fBLOG_INFO\fR.
+Messages are logged with an id of \fBfetchmail\fP, the facility \fBLOG_MAIL\fP,
+and priorities \fBLOG_ERR\fP, \fBLOG_ALERT\fP or \fBLOG_INFO\fP.
This option is intended for logging status and error messages which
indicate the status of the daemon and the results while fetching mail
from the server(s).
-Error messages for command line options and parsing the \fI.fetchmailrc\fR
+Error messages for command line options and parsing the \fI.fetchmailrc\fP
file are still written to stderr, or to the specified log file.
The
.B \-\-nosyslog
option turns off use of
-.IR syslog (3),
-assuming it's turned on in the
-.I ~/.fetchmailrc
-file, or that the
-.B \-L
-or
-.B \-\-logfile <file>
-option was used.
+.BR syslog (3),
+assuming it's turned on in the \fI~/.fetchmailrc\fP file.
+This option is overridden, in certain situations, by \fB\-\-logfile\fP (which
+see).
.PP
The
.B \-N
or
-.B --nodetach
-option suppresses backgrounding and detachment of the
-daemon process from its control terminal. This is useful
-for debugging or when fetchmail runs as the child of a supervisor
-process such as
-.IR init (8)
+.B \-\-nodetach
+option suppresses backgrounding and detachment of the daemon process
+from its control terminal. This is useful for debugging or when
+fetchmail runs as the child of a supervisor process such as
+.BR init (8)
or Gerrit Pape's
-.I runit.
-Note that this also causes the logfile option to be
-ignored (though perhaps it shouldn't).
+.BR runit (8).
+Note that this also causes the logfile option to be ignored.
.PP
Note that while running in daemon mode polling a POP2 or IMAP2bis server,
transient errors (such as DNS failures or sendmail delivery refusals)
next poll cycle. (The IMAP logic doesn't delete messages until
they're delivered, so this problem does not arise.)
.PP
-If you touch or change the
-.I ~/.fetchmailrc
-file while fetchmail is running in daemon mode, this will be detected
-at the beginning of the next poll cycle. When a changed
-.I ~/.fetchmailrc
-is detected, fetchmail rereads it and restarts from scratch (using
-exec(2); no state information is retained in the new instance). Note also
-that if you break the
-.I ~/.fetchmailrc
-file's syntax, the new instance will softly and silently vanish away
-on startup.
+If you touch or change the \fI~/.fetchmailrc\fP file while fetchmail is
+running in daemon mode, this will be detected at the beginning of the
+next poll cycle. When a changed \fI~/.fetchmailrc\fP is detected,
+fetchmail rereads it and restarts from scratch (using exec(2); no state
+information is retained in the new instance). Note that if fetchmail
+needs to query for passwords, of that if you break the
+\fI~/.fetchmailrc\fP file's syntax, the new instance will softly and
+silently vanish away on startup.
.SH ADMINISTRATIVE OPTIONS
.PP
the 'bouncemail' global option is off and additionally for spam-blocked
mail if the 'bouncemail' global option is off and the 'spambounce'
global option is on. This option defaults to the user who invoked
-.IR fetchmail .
+\fBfetchmail\fP.
If the invoking user is root, then the default of this option is
the user 'postmaster'. Setting postmaster to the empty string causes
such mail as described above to be discarded - this however is usually a
The
.B \-\-showdots
option (keyword: set showdots) forces fetchmail to show progress dots
-even if the current tty is not stdout (for example logfiles).
-Starting with fetchmail version 5.3.0,
-progress dots are only shown on stdout by default.
+even if the output goes to a file or fetchmail is not in verbose mode.
+Fetchmail shows the dots by default when run in \-\-verbose mode
+\fIand\fP output goes to console. This option is ignored in \-\-silent mode.
.PP
By specifying the
.B \-\-tracepolls
this is called 'tracepolls'.
.SH RETRIEVAL FAILURE MODES
-The protocols \fIfetchmail\fR uses to talk to mailservers are next to
+The protocols \fBfetchmail\fP uses to talk to mailservers are next to
bulletproof. In normal operation forwarding to port 25, no message is
ever deleted (or even marked for deletion) on the host until the SMTP
-listener on the client side has acknowledged to \fIfetchmail\fR that
+listener on the client side has acknowledged to \fBfetchmail\fP that
the message has been either accepted for delivery or rejected due to a
spam block.
.PP
When forwarding to an MDA, however, there is more possibility
of error. Some MDAs are 'safe' and reliably return a nonzero status
on any delivery error, even one due to temporary resource limits.
-The well-known
-.IR procmail (1)
+The
+.BR maildrop (1)
program is like this; so are most programs designed as mail transport
agents, such as
-.IR sendmail (1),
-and
-.IR exim (1).
+.BR sendmail (1),
+including the sendmail wrapper of Postfix and
+.BR exim (1).
These programs give back a reliable positive acknowledgement and
can be used with the mda option with no risk of mail loss. Unsafe
MDAs, though, may return 0 even on delivery failure. If this
happens, you will lose mail.
.PP
-The normal mode of \fIfetchmail\fR is to try to download only 'new'
+The normal mode of \fBfetchmail\fP is to try to download only 'new'
messages, leaving untouched (and undeleted) messages you have already
read directly on the server (or fetched with a previous \fIfetchmail
---keep\fR). But you may find that messages you've already read on the
+\-\-keep\fP). But you may find that messages you've already read on the
server are being fetched (and deleted) even when you don't specify
---all. There are several reasons this can happen.
+\-\-all. There are several reasons this can happen.
.PP
One could be that you're using POP2. The POP2 protocol includes no
-representation of 'new' or 'old' state in messages, so \fIfetchmail\fR
+representation of 'new' or 'old' state in messages, so \fBfetchmail\fP
must treat all messages as new all the time. But POP2 is obsolete, so
this is unlikely.
.PP
A potential POP3 problem might be servers that insert messages
in the middle of mailboxes (some VMS implementations of mail are
-rumored to do this). The \fIfetchmail\fR code assumes that new
+rumored to do this). The \fBfetchmail\fP code assumes that new
messages are appended to the end of the mailbox; when this is not true
-it may treat some old messages as new and vice versa. Using UIDL might
-fix this, otherwise, consider switching to IMAP.
+it may treat some old messages as new and vice versa. Using UIDL whilst
+setting fastuidl 0 might fix this, otherwise, consider switching to IMAP.
.PP
Yet another POP3 problem is that if they can't make tempfiles in the
user's home directory, some POP3 servers will hand back an
this, though it's not specified by the IMAP RFCs. If you ever trip over
a server that doesn't, the symptom will be that messages you have
already read on your host will look new to the server. In this
-(unlikely) case, only messages you fetched with \fIfetchmail --keep\fR
+(unlikely) case, only messages you fetched with \fIfetchmail \-\-keep\fP
will be both undeleted and marked old.
.PP
-In ETRN and ODMR modes, \fIfetchmail\fR does not actually retrieve messages;
+In ETRN and ODMR modes, \fBfetchmail\fP does not actually retrieve messages;
instead, it asks the server's SMTP listener to start a queue flush
to the client via SMTP. Therefore it sends only undelivered messages.
(unfortunately) varies according to the listener.
.PP
Newer versions of
-.I sendmail
+\fBsendmail\fP
return an error code of 571.
.PP
According to RFC2821, the correct thing to return in this situation is
reasons].").
.PP
Older versions of the
-.I exim
+\fBexim\fP
MTA return 501 "Syntax error in parameters or arguments".
.PP
The
-.I postfix
+\fBpostfix\fP
MTA runs 554 as an antispam response.
.PP
-.I Zmailer
+\fBZmailer\fP
may reject code with a 500 response (followed by an enhanced status
code that contains more information).
.PP
Return codes which
-.I fetchmail
+\fBfetchmail\fP
treats as antispam responses and discards
the message can be set with the 'antispam' option. This is one of the
-.I only
+\fIonly\fP
three circumstance under which fetchmail ever discards mail (the others
are the 552 and 553 errors described below, and the suppression of
multidropped messages with a message-ID already seen).
.PP
If
-.I fetchmail
+\fBfetchmail\fP
is fetching from an IMAP server, the antispam response will be detected and
the message rejected immediately after the headers have been fetched,
without reading the message body. Thus, you won't pay for downloading
.PP
By default, the list of antispam responses is empty.
.PP
-If the \fIspambounce\fR global option is on, mail that is spam-blocked
+If the \fIspambounce\fP global option is on, mail that is spam-blocked
triggers an RFC1892/RFC1894 bounce message informing the originator that
we do not accept mail from it. See also BUGS.
.SH THE RUN CONTROL FILE
The preferred way to set up fetchmail is to write a
-\&\fI.fetchmailrc\fR file in your home directory (you may do this
-directly, with a text editor, or indirectly via \fIfetchmailconf\fR).
+\&\fI.fetchmailrc\fP file in your home directory (you may do this
+directly, with a text editor, or indirectly via \fBfetchmailconf\fP).
When there is a conflict between the command-line arguments and the
arguments in this file, the command-line arguments take precedence.
.PP
To protect the security of your passwords,
-your \fI~/.fetchmailrc\fR may not normally have more than 0600 (u=rw,g=,o=) permissions;
-.I fetchmail
+your \fI~/.fetchmailrc\fP may not normally have more than 0700 (u=rwx,g=,o=) permissions;
+\fBfetchmail\fP
will complain and exit otherwise (this check is suppressed when
---version is on).
+\-\-version is on).
.PP
-You may read the \fI.fetchmailrc\fR file as a list of commands to
+You may read the \fI.fetchmailrc\fP file as a list of commands to
be executed when
-.I fetchmail
+\fBfetchmail\fP
is called with no arguments.
.SS Run Control Syntax
.PP
There are four kinds of tokens: grammar keywords, numbers
(i.e. decimal digit sequences), unquoted strings, and quoted strings.
A quoted string is bounded by double quotes and may contain
-whitespace (and quoted digits are treated as a string). An unquoted
-string is any whitespace-delimited token that is neither numeric, string
-quoted nor contains the special characters ',', ';', ':', or '='.
+whitespace (and quoted digits are treated as a string). Note that
+quoted strings will also contain line feed characters if they run across
+two or more lines, unless you use a backslash to join lines (see below).
+An unquoted string is any whitespace-delimited token that is neither
+numeric, string quoted nor contains the special characters ',', ';',
+\&':', or '='.
.PP
Any amount of whitespace separates tokens in server entries, but is
-otherwise ignored. You may use standard C-style escapes (\en, \et,
-\eb, octal, and hex) to embed non-printable characters or string
-delimiters in strings.
+otherwise ignored. You may use backslash escape sequences (\en for LF,
+\&\et for HT, \eb for BS, \er for CR, \e\fInnn\fP for decimal (where
+nnn cannot start with a 0), \e0\fIooo\fP for octal, and \ex\fIhh\fP for
+hex) to embed non-printable characters or string delimiters in strings.
+In quoted strings, a backslash at the very end of a line will cause the
+backslash itself and the line feed (LF or NL, new line) character to be
+ignored, so that you can wrap long strings. Without the backslash at the
+line end, the line feed character would become part of the string.
+.PP
+\fBWarning:\fP
+while these resemble C-style escape sequences, they are not the same.
+fetchmail only supports these eight styles. C supports more escape
+sequences that consist of backslash (\e) and a single character, but
+does not support decimal codes and does not require the leading 0 in
+octal notation. Example: fetchmail interprets \e233 the same as \exE9
+(Latin small letter e with acute), where C would interpret \e233 as
+octal 0233 = \ex9B (CSI, control sequence introducer).
.PP
Each server entry consists of one of the keywords 'poll' or 'skip',
followed by a server name, followed by server options, followed by any
-number of user descriptions. Note: the most common cause of syntax
-errors is mixing up user and server options.
+number of user (or username) descriptions, followed by user options.
+Note: the most common cause of syntax errors is mixing up user and
+server options or putting user options before the user descriptions.
.PP
For backward compatibility, the word 'server' is a synonym for 'poll'.
.PP
.SS Poll vs. Skip
The 'poll' verb tells fetchmail to query this host when it is run with
no arguments. The 'skip' verb tells
-.I fetchmail
+\fBfetchmail\fP
not to poll this host unless it is explicitly named on the command
line. (The 'skip' verb allows you to experiment with test entries
safely, or easily disable entries for hosts that are temporarily down.)
.SS Keyword/Option Summary
Here are the legal options. Keyword suffixes enclosed in
square brackets are optional. Those corresponding to short command-line
-options are followed by '-' and the appropriate option letter. If
+options are followed by '\-' and the appropriate option letter. If
option is only relevant to a single mode of operation, it is noted as
-'s' or 'm' for singledrop- or multidrop-mode, respectively.
+\&'s' or 'm' for singledrop- or multidrop-mode, respectively.
Here are the legal global options:
l l l lw34.
Keyword Opt Mode Function
_
-set daemon -d \& T{
+set daemon \-d \& T{
Set a background poll interval in seconds.
T}
set postmaster \& \& T{
is sent with false sender address and thus this option hurts innocent
bystanders.
T}
-set logfile -L \& T{
-Name of a file to append error and status messages to.
+set no softbounce \& \& T{
+Delete permanently undeliverable mail. It is recommended to use this
+option if the configuration has been thoroughly tested.
+T}
+set softbounce \& \& T{
+Keep permanently undeliverable mail as though a temporary error had
+occurred (default).
+T}
+set logfile \-L \& T{
+Name of a file to append error and status messages to. Only effective
+in daemon mode and if fetchmail detaches. If effective, overrides \fBset
+syslog\fP.
T}
-set idfile -i \& T{
+set idfile \-i \& T{
Name of the file to store UID lists in.
T}
set syslog \& \& T{
-Do error logging through syslog(3).
+Do error logging through syslog(3). May be overriden by \fBset
+logfile\fP.
T}
set no syslog \& \& T{
Turn off error logging through syslog(3). (default)
via \& \& T{
Specify DNS name of mailserver, overriding poll name
T}
-proto[col] -p \& T{
+proto[col] \-p \& T{
Specify protocol (case insensitive):
POP2, POP3, IMAP, APOP, KPOP
T}
local[domains] \& m T{
Specify domain(s) to be regarded as local
T}
-port \& T{
+port \& \& T{
Specify TCP/IP service port (obsolete, use 'service' instead).
T}
-service -P \& T{
+service \-P \& T{
Specify service name (a numeric value is also allowed and
considered a TCP/IP port number).
T}
auth[enticate] \& \& T{
Set authentication type (default 'any')
T}
-timeout -t \& T{
+timeout \-t \& T{
Server inactivity timeout in seconds (default 300)
T}
-envelope -E m T{
+envelope \-E m T{
Specify envelope-address header name
T}
no envelope \& m T{
Disable looking for envelope address
T}
-qvirtual -Q m T{
+qvirtual \-Q m T{
Qmail virtual domain prefix to remove from user name
T}
aka \& m T{
Specify alternate DNS names of mailserver
T}
-interface -I \& T{
+interface \-I \& T{
specify IP interface(s) that must be up for server poll to take place
T}
-monitor -M \& T{
+monitor \-M \& T{
Specify IP address to monitor for activity
T}
plugin \& \& T{
plugout \& \& T{
Specify command through which to make listener connections.
T}
-dns \& m T{
+dns \& m T{
Enable DNS lookup for multidrop (default)
T}
no dns \& m T{
no checkalias \& m T{
Do comparison by name for multidrop (default)
T}
-uidl -U \& T{
+uidl \-U \& T{
Force POP3 to use client-side UIDLs (recommended)
T}
no uidl \& \& T{
Add poll tracing information to the Received header
T}
principal \& \& T{
-Set Kerberos principal (only useful with imap and kerberos)
+Set Kerberos principal (only useful with IMAP and kerberos)
T}
esmtpname \& \& T{
Set name for RFC2554 authentication to the ESMTP server.
T}
-esmtppassword \& \& T{
+esmtppassword \& \& T{
Set password for RFC2554 authentication to the ESMTP server.
T}
+bad-header \& \& T{
+How to treat messages with a bad header. Can be reject (default) or accept.
+T}
.TE
-Here are the legal user options:
+Here are the legal user descriptions and options:
.TS
l l l lw34.
Keyword Opt Mode Function
_
-user[name] -u \& T{
-Set remote user name
-(local user name if name followed by 'here')
+user[name] \-u \& T{
+This is the user description and must come first after server
+description and after possible server options, and before user options.
+.br
+It sets the remote user name if by itself or followed by 'there', or the
+local user name if followed by 'here'.
T}
is \& \& T{
Connect local and remote user names
Connect to server over the specified base protocol using SSL encryption
T}
sslcert \& \& T{
-Specify file for client side public SSL certificate
+Specify file for \fBclient side\fP public SSL certificate
+T}
+sslcertfile \& \& T{
+Specify file with trusted CA certificates
+T}
+sslcertpath \& \& T{
+Specify c_rehash-ed directory with trusted CA certificates.
T}
sslkey \& \& T{
-Specify file for client side private SSL key
+Specify file for \fBclient side\fP private SSL key
T}
sslproto \& \& T{
Force ssl protocol for connection
T}
-folder -r \& T{
+folder \-r \& T{
Specify remote folder to query
T}
-smtphost -S \& T{
+smtphost \-S \& T{
Specify smtp host(s) to forward to
T}
fetchdomains \& m T{
Specify domains for which mail should be fetched
T}
-smtpaddress -D \& T{
+smtpaddress \-D \& T{
Specify the domain to be put in RCPT TO lines
T}
smtpname \& \& T{
Specify the user and domain to be put in RCPT TO lines
T}
-antispam -Z \& T{
+antispam \-Z \& T{
Specify what SMTP returns are interpreted as spam-policy blocks
T}
-mda -m \& T{
+mda \-m \& T{
Specify MDA for local delivery
T}
-bsmtp -o \& T{
+bsmtp \-o \& T{
Specify BSMTP batch file to append to
T}
preconnect \& \& T{
postconnect \& \& T{
Command to be executed after each connection
T}
-keep -k \& T{
-Don't delete seen messages from server
+keep \-k \& T{
+Don't delete seen messages from server (for POP3, uidl is recommended)
T}
-flush -F \& T{
+flush \-F \& T{
Flush all seen messages before querying (DANGEROUS)
T}
limitflush \& \& T{
Flush all oversized messages before querying
T}
-fetchall -a \& T{
+fetchall \-a \& T{
Fetch all messages whether seen or not
T}
rewrite \& \& T{
idle \& \& T{
Idle waiting for new messages after each poll (IMAP only)
T}
-no keep -K \& T{
+no keep \-K \& T{
Delete seen messages from server (default)
T}
no flush \& \& T{
Don't drop Status headers (default)
T}
no dropdelivered \& \& T{
-Don't drop Delivered-To headers (default)
+Don't drop Delivered\-To headers (default)
T}
no mimedecode \& \& T{
Don't convert quoted-printable to 8-bit in MIME messages (default)
no idle \& \& T{
Don't idle waiting for new messages after each poll (IMAP only)
T}
-limit -l \& T{
+limit \-l \& T{
Set message size limit
T}
-warnings -w \& T{
+warnings \-w \& T{
Set message size warning interval
T}
-batchlimit -b \& T{
+batchlimit \-b \& T{
Max # messages to forward in single connect
T}
-fetchlimit -B \& T{
+fetchlimit \-B \& T{
Max # messages to fetch in single connect
T}
fetchsizelimit \& \& T{
fastuidl \& \& T{
Use binary search for first unseen message (POP3 only)
T}
-expunge -e \& T{
+expunge \-e \& T{
Perform an expunge on every #th message (IMAP and POP3 only)
T}
properties \& \& T{
T}
.TE
.PP
-Remember that all user options must \fIfollow\fR all server options.
+All user options must begin with a user description (user or username
+option) and \fIfollow\fP all server descriptions and options.
.PP
In the .fetchmailrc file, the 'envelope' string argument may be
preceded by a whitespace-separated number. This number, if specified,
\&'checkalias'/'no checkalias', 'password', 'preconnect', 'postconnect',
\&'localdomains', 'stripcr'/'no stripcr', 'forcecr'/'no forcecr',
\&'pass8bits'/'no pass8bits' 'dropstatus/no dropstatus',
-\&'dropdelivered/no dropdelivered', 'mimedecode/no mimedecode', 'idle/no
-idle', and 'no envelope'.
+\&'dropdelivered/no dropdelivered', 'mimedecode/no mimedecode', 'no idle',
+and 'no envelope'.
.PP
The 'via' option is for if you want to have more
than one configuration pointing at the same site. If it is present,
server less frequently than the basic poll interval. If you say
\&'interval N' the server this option is attached to will only be
queried every N poll intervals.
+.SS Singledrop vs. Multidrop options
+.PP
+Please ensure you read the section titled
+\fBTHE USE AND ABUSE OF MULTIDROP MAILBOXES \fP
+if you intend to use multidrop mode.
.PP
The 'is' or 'to' keywords associate the following local (client)
name(s) (or server-name to client-name mappings separated by =) with
the mailserver user name in the entry. If an is/to list has '*' as
-its last name, unrecognized names are simply passed through.
+its last name, unrecognized names are simply passed through. Note that
+until \fBfetchmail\fP version 6.3.4 inclusively, these lists could only
+contain local parts of user names (fetchmail would only look at the part
+before the @ sign). \fBfetchmail\fP versions 6.3.5 and
+newer support full addresses on the left hand side of these mappings,
+and they take precedence over any 'localdomains', 'aka', 'via' or
+similar mappings.
.PP
A single local name can be used to support redirecting your mail when
your username on the client machine is different from your name on the
mailserver. When there is only a single local name, mail is forwarded
to that local username regardless of the message's Received, To, Cc,
-and Bcc headers. In this case
-.I fetchmail
+and Bcc headers. In this case,
+\fBfetchmail\fP
never does DNS lookups.
.PP
-When there is more than one local name (or name mapping) the
-\fIfetchmail\fR code does look at the Received, To, Cc, and Bcc
-headers of retrieved mail (this is 'multidrop mode'). It looks for
-addresses with hostname parts that match your poll name or your 'via',
-\&'aka' or 'localdomains' options, and usually also for hostname parts
-which DNS tells it are aliases of the mailserver. See the discussion
-of 'dns', 'checkalias', 'localdomains', and 'aka' for details on how
-matching addresses are handled.
-.PP
-If \fIfetchmail\fR cannot match any mailserver usernames or
+When there is more than one local name (or name mapping),
+\fBfetchmail\fP looks at the envelope header, if configured, and
+otherwise at the Received, To, Cc, and Bcc headers of retrieved mail
+(this is 'multidrop mode'). It looks for addresses with hostname parts
+that match your poll name or your 'via', 'aka' or 'localdomains'
+options, and usually also for hostname parts which DNS tells it are
+aliases of the mailserver. See the discussion of 'dns', 'checkalias',
+\&'localdomains', and 'aka' for details on how matching addresses are
+handled.
+.PP
+If \fBfetchmail\fP cannot match any mailserver usernames or
localdomain addresses, the mail will be bounced.
Normally it will be bounced to the sender, but if the 'bouncemail'
global option is off, the mail will go to the local postmaster instead.
.PP
The 'dns' option (normally on) controls the way addresses from
multidrop mailboxes are checked. On, it enables logic to check each
-host address that doesn't match an 'aka' or 'localdomains' declaration
+host address that does not match an 'aka' or 'localdomains' declaration
by looking it up with DNS. When a mailserver username is recognized
attached to a matching hostname part, its local mapping is added to
the list of local recipients.
remote MTAs that identify themselves using their canonical name, while
they're polled using an alias.
When such a server is polled, checks to extract the envelope address
-fail, and
-.IR fetchmail
-reverts to delivery using the To/Cc/Bcc headers (See below
-\&'Header vs. Envelope addresses').
-Specifying this option instructs
-.IR fetchmail
-to retrieve all the IP addresses associated with both the poll name
-and the name used by the remote MTA and to do a comparison of the IP
-addresses. This comes in handy in situations where the remote server
-undergoes frequent canonical name changes, that would otherwise
-require modifications to the rcfile. 'checkalias' has no effect if
-\&'no dns' is specified in the rcfile.
+fail, and \fBfetchmail\fP reverts to delivery using the To/Cc/Bcc
+headers (See below \&'Header vs. Envelope addresses').
+Specifying this option instructs \fBfetchmail\fP to retrieve all the IP
+addresses associated with both the poll name and the name used by the
+remote MTA and to do a comparison of the IP addresses. This comes in
+handy in situations where the remote server undergoes frequent canonical
+name changes, that would otherwise require modifications to the rcfile.
+\&'checkalias' has no effect if \&'no dns' is specified in the rcfile.
.PP
The 'aka' option is for use with multidrop mailboxes. It allows you
to pre-declare a list of DNS aliases for a server. This is an
optimization hack that allows you to trade space for speed. When
-.IR fetchmail ,
-while processing a multidrop mailbox, grovels through message headers
-looking for names of the mailserver, pre-declaring common ones can
-save it from having to do DNS lookups. Note: the names you give
-as arguments to 'aka' are matched as suffixes -- if you specify
-(say) 'aka netaxs.com', this will match not just a hostname
-netaxs.com, but any hostname that ends with '.netaxs.com'; such as
-(say) pop3.netaxs.com and mail.netaxs.com.
+\fBfetchmail\fP, while processing a multidrop mailbox, grovels through
+message headers looking for names of the mailserver, pre-declaring
+common ones can save it from having to do DNS lookups. Note: the names
+you give as arguments to 'aka' are matched as suffixes -- if you specify
+(say) 'aka netaxs.com', this will match not just a hostname netaxs.com,
+but any hostname that ends with '.netaxs.com'; such as (say)
+pop3.netaxs.com and mail.netaxs.com.
.PP
The 'localdomains' option allows you to declare a list of domains
which fetchmail should consider local. When fetchmail is parsing
address lines in multidrop modes, and a trailing segment of a host
name matches a declared local domain, that address is passed through
-to the listener or MDA unaltered (local-name mappings are \fInot\fR
+to the listener or MDA unaltered (local-name mappings are \fInot\fP
applied).
.PP
-If you are using 'localdomains', you may also need to specify \&'no
-envelope', which disables \fIfetchmail\fR's normal attempt to deduce
+If you are using 'localdomains', you may also need to specify 'no
+envelope', which disables \fBfetchmail\fP's normal attempt to deduce
an envelope address from the Received line or X-Envelope-To header or
whatever header has been previously set by 'envelope'. If you set 'no
envelope' in the defaults entry it is possible to undo that in
\&'envelope "Received"' restores the default parsing of
Received lines.
.PP
-The \fBpassword\fR option requires a string argument, which is the password
+The \fBpassword\fP option requires a string argument, which is the password
to be used with the entry's server.
.PP
The 'preconnect' keyword allows you to specify a shell command to be
executed just before each time
-.I fetchmail
+\fBfetchmail\fP
establishes a mailserver connection. This may be useful if you are
attempting to set up secure POP connections with the aid of
-.IR ssh (1).
+.BR ssh (1).
If the command returns a nonzero status, the poll of that mailserver
will be aborted.
.PP
The 'pass8bits' option exists to cope with Microsoft mail programs that
stupidly slap a "Content-Transfer-Encoding: 7bit" on everything. With
this option off (the default) and such a header present,
-.I fetchmail
+\fBfetchmail\fP
declares BODY=7BIT to an ESMTP-capable listener; this causes problems for
messages actually using 8-bit ISO or KOI-8 character sets, which will
be garbled by having the high bits of all characters stripped. If
\&'pass8bits' is on,
-.I fetchmail
+\fBfetchmail\fP
is forced to declare BODY=8BITMIME to any ESMTP-capable listener. If
the listener is 8-bit-clean (as all the major ones now are) the right
thing will probably result.
Status line in it has been seen. (Note: the empty Status lines
inserted by some buggy POP servers are unconditionally discarded.)
.PP
-The 'dropdelivered' option controls whether Delivered-To headers will
+The 'dropdelivered' option controls whether Delivered\-To headers will
be kept in fetched mail (the default) or discarded. These headers are
added by Qmail and Postfix mailservers in order to avoid mail loops but
may get in your way if you try to "mirror" a mailserver within the same
can save bandwidth by eliminating TCP/IP connects and LOGIN/LOGOUT
sequences. On the other hand, an IDLE connection will eat almost all
of your fetchmail's time, because it will never drop the connection
-and allow other pools to occur unless the server times out the IDLE.
+and allow other polls to occur unless the server times out the IDLE.
It also doesn't work with multiple folders; only the first folder will
ever be polled.
The 'properties' option is an extension mechanism. It takes a string
argument, which is ignored by fetchmail itself. The string argument may be
used to store configuration information for scripts which require it.
-In particular, the output of '--configdump' option will make properties
+In particular, the output of '\-\-configdump' option will make properties
associated with a user entry readily available to a Python script.
.PP
.SS Miscellaneous Run Control Options
Legal protocol identifiers for use with the 'protocol' keyword are:
.sp
.nf
- auto (or AUTO)
+ auto (or AUTO) (legacy, to be removed from future release)
pop2 (or POP2) (legacy, to be removed from future release)
pop3 (or POP3)
sdps (or SDPS)
.sp
.PP
Legal authentication types are 'any', 'password', 'kerberos',
-\&'kerberos_v4', 'kerberos_v5' and 'gssapi', 'cram-md5', 'otp', 'msn'
-(only for POP3), 'ntlm', 'ssh'. The 'password' type specifies
+\&'kerberos_v4', 'kerberos_v5' and 'gssapi', 'cram\-md5', 'otp', 'msn'
+(only for POP3), 'ntlm', 'ssh', 'external' (only IMAP).
+The 'password' type specifies
authentication by normal transmission of a password (the password may be
-plain text or subject to protocol-specific encryption as in APOP);
-\&'kerberos' tells \fIfetchmail\fR to try to get a Kerberos ticket at the
+plain text or subject to protocol-specific encryption as in CRAM-MD5);
+\&'kerberos' tells \fBfetchmail\fP to try to get a Kerberos ticket at the
start of each query instead, and send an arbitrary string as the
password; and 'gssapi' tells fetchmail to use GSSAPI authentication.
See the description of the 'auth' keyword for more.
authentication. These defaults may be overridden by later options.
.PP
There are some global option statements: 'set logfile'
-followed by a string sets the same global specified by --logfile. A
-command-line --logfile option will override this. Note that --logfile is
-only effective if fetchmail detaches itself from the terminal. Also,
-'set daemon' sets the poll interval as --daemon does. This can be
-overridden by a command-line --daemon option; in particular --daemon 0
+followed by a string sets the same global specified by \-\-logfile. A
+command-line \-\-logfile option will override this. Note that \-\-logfile is
+only effective if fetchmail detaches itself from the terminal, is in
+daemon mode, and if the
+logfile already exists before fetchmail is run, and it overrides
+\-\-syslog in this case. Also,
+\&'set daemon' sets the poll interval as \-\-daemon does. This can be
+overridden by a command-line \-\-daemon option; in particular \-\-daemon\~0
can be used to force foreground operation. The 'set postmaster'
statement sets the address to which multidrop mail defaults if there are
no local matches. Finally, 'set syslog' sends log messages to
syslogd(8).
+.SH DEBUGGING FETCHMAIL
+.SS Fetchmail crashing
+There are various ways in that fetchmail may "crash", i. e. stop
+operation suddenly and unexpectedly. A "crash" usually refers to an
+error condition that the software did not handle by itself. A well-known
+failure mode is the "segmentation fault" or "signal 11" or "SIGSEGV" or
+just "segfault" for short. These can be caused by hardware or by software
+problems. Software-induced segfaults can usually be reproduced easily
+and in the same place, whereas hardware-induced segfaults can go away if
+the computer is rebooted, or powered off for a few hours, and can happen
+in random locations even if you use the software the same way.
+
+For solving hardware-induced segfaults, find the faulty component and repair or
+replace it.
+.URL http://www.bitwizard.nl/sig11/ "The Sig11 FAQ"
+may help you with details.
+
+For solving software-induced segfaults, the developers may need a "stack
+backtrace".
+
+.SS Enabling fetchmail core dumps
+By default, fetchmail suppresses core dumps as these might contain
+passwords and other sensitive information. For debugging fetchmail
+crashes, obtaining a "stack backtrace" from a core dump is often the
+quickest way to solve the problem, and when posting your problem on a
+mailing list, the developers may ask you for a "backtrace".
+
+1. To get useful backtraces, fetchmail needs to be installed without
+getting stripped of its compilation symbols. Unfortunately, most
+binary packages that are installed are stripped, and core files from
+symbol-stripped programs are worthless. So you may need to recompile
+fetchmail. On many systems, you can type
+.sp
+.nf
+ file `which fetchmail`
+.fi
+.sp
+to find out if fetchmail was symbol-stripped or not. If yours was
+unstripped, fine, proceed, if it was stripped, you need to recompile the
+source code first. You do not usually need to install fetchmail in order
+to debug it.
+
+2. The shell environment that starts fetchmail needs to enable core
+dumps. The key is the "maximum core (file) size" that can usually be
+configured with a tool named "limit" or "ulimit". See the documentation
+for your shell for details. In the popular bash shell, "ulimit \-Sc
+unlimited" will allow the core dump.
+
+3. You need to tell fetchmail, too, to allow core dumps. To do
+this, run fetchmail with the \fB\-d0 \-v\fP options. It is often easier
+to also add \fB\-\-nosyslog \-N\fP as well.
+
+Finally, you need to reproduce the crash. You can just start fetchmail
+from the directory where you compiled it by typing \fB./fetchmail\fP,
+so the complete command line will start with \fB./fetchmail \-Nvd0
+\&\-\-nosyslog\fP and perhaps list your other options.
+
+After the crash, run your debugger to obtain the core dump. The
+debugger will often be GNU GDB, you can then type (adjust paths as
+necessary) \fBgdb ./fetchmail fetchmail.core\fP and then, after GDB
+has started up and read all its files, type \fBbacktrace full\fP, save
+the output (copy & paste will do, the backtrace will be read by a human)
+and then type \fBquit\fP to leave gdb.
+\fBNote:\fP
+on some systems, the core
+files have different names, they might contain a number instead of the
+program name, or number and name, but it will usually have "core" as
+part of their name.
+
.SH INTERACTION WITH RFC 822
When trying to determine the originating address of a message,
fetchmail looks through headers in the following order:
rather to the list manager (which is less annoying).
In multidrop mode, destination headers are processed as follows:
-First, fetchmail looks for the Received: header (or whichever one is
-specified by the 'envelope' option) to determine the local
-recipient address. If the mail is addressed to more than one recipient,
-the Received line won't contain any information regarding recipient addresses.
+First, fetchmail looks for the header specified by the 'envelope' option
+in order to determine the local recipient address. If the mail is
+addressed to more than one recipient, the Received line won't contain
+any information regarding recipient addresses.
Then fetchmail looks for the Resent-To:, Resent-Cc:, and Resent-Bcc:
lines. If they exist, they should contain the final recipients and
-have precedence over their To:/Cc:/Bcc: counterparts. If the Resent-*
+have precedence over their To:/Cc:/Bcc: counterparts. If the Resent\-*
lines don't exist, the To:, Cc:, Bcc: and Apparently-To: lines are
-looked for. (The presence of a Resent-To: is taken to imply that the
+looked for. (The presence of a Resent\-To: is taken to imply that the
person referred by the To: address has already received the original
copy of the mail.)
file, where they can be used not just by fetchmail but by ftp(1) and
other programs.
-Basic format is:
+The basic format is:
+
+.IP
+poll \fISERVERNAME\fP protocol \fIPROTOCOL\fP username \fINAME\fP
+password \fIPASSWORD\fP
-.nf
- poll SERVERNAME protocol PROTOCOL username NAME password PASSWORD
-.fi
.PP
Example:
+.IP
.nf
- poll pop.provider.net protocol pop3 username "jsmith" password "secret1"
+poll pop.provider.net protocol pop3 username "jsmith" password "secret1"
.fi
+
.PP
Or, using some abbreviations:
+.IP
.nf
- poll pop.provider.net proto pop3 user "jsmith" password "secret1"
+poll pop.provider.net proto pop3 user "jsmith" password "secret1"
.fi
+
.PP
Multiple servers may be listed:
+.IP
.nf
- poll pop.provider.net proto pop3 user "jsmith" pass "secret1"
- poll other.provider.net proto pop2 user "John.Smith" pass "My^Hat"
+poll pop.provider.net proto pop3 user "jsmith" pass "secret1"
+poll other.provider.net proto pop2 user "John.Smith" pass "My^Hat"
.fi
-Here's a version of those two with more whitespace and some noise words:
+.PP
+Here's the same version with more whitespace and some noise words:
+.IP
.nf
- poll pop.provider.net proto pop3
- user "jsmith", with password secret1, is "jsmith" here;
- poll other.provider.net proto pop2:
- user "John.Smith", with password "My^Hat", is "John.Smith" here;
+poll pop.provider.net proto pop3
+ user "jsmith", with password secret1, is "jsmith" here;
+poll other.provider.net proto pop2:
+ user "John.Smith", with password "My^Hat", is "John.Smith" here;
.fi
-This version is much easier to read and doesn't cost significantly
-more (parsing is done only once, at startup time).
-
.PP
-If you need to include whitespace in a parameter string, enclose the
-string in double quotes. Thus:
+If you need to include whitespace in a parameter string or start the
+latter with a number, enclose the string in double quotes. Thus:
+.IP
.nf
- poll mail.provider.net with proto pop3:
- user "jsmith" there has password "u can't krak this"
- is jws here and wants mda "/bin/mail"
+poll mail.provider.net with proto pop3:
+ user "jsmith" there has password "4u but u can't krak this"
+ is jws here and wants mda "/bin/mail"
.fi
+.PP
You may have an initial server description headed by the keyword
\&'defaults' instead of 'poll' followed by a name. Such a record
is interpreted as defaults for all queries to use. It may be overwritten
by individual server descriptions. So, you could write:
+.IP
.nf
- defaults proto pop3
- user "jsmith"
- poll pop.provider.net
- pass "secret1"
- poll mail.provider.net
- user "jjsmith" there has password "secret2"
+defaults proto pop3
+ user "jsmith"
+poll pop.provider.net
+ pass "secret1"
+poll mail.provider.net
+ user "jjsmith" there has password "secret2"
.fi
-It's possible to specify more than one user per server (this is only
-likely to be useful when running fetchmail in daemon mode as root).
+.PP
+It's possible to specify more than one user per server.
The 'user' keyword leads off a user description, and every user specification
in a multi-user entry must include it. Here's an example:
+.IP
.nf
- poll pop.provider.net proto pop3 port 3111
- user "jsmith" with pass "secret1" is "smith" here
- user jones with pass "secret2" is "jjones" here keep
+poll pop.provider.net proto pop3 port 3111
+ user "jsmith" with pass "secret1" is "smith" here
+ user jones with pass "secret2" is "jjones" here keep
.fi
+.PP
This associates the local username 'smith' with the pop.provider.net
username 'jsmith' and the local username 'jjones' with the
pop.provider.net username 'jones'. Mail for 'jones' is kept on the
server after download.
+
.PP
-Here's what a simple retrieval configuration for a multi-drop mailbox
+Here's what a simple retrieval configuration for a multidrop mailbox
looks like:
+.IP
.nf
- poll pop.provider.net:
- user maildrop with pass secret1 to golux 'hurkle'='happy' snark here
+poll pop.provider.net:
+ user maildrop with pass secret1 to golux 'hurkle'='happy' snark here
.fi
+.PP
This says that the mailbox of account 'maildrop' on the server is a
-multi-drop box, and that messages in it should be parsed for the
+multidrop box, and that messages in it should be parsed for the
server user names 'golux', 'hurkle', and 'snark'. It further
specifies that 'golux' and 'snark' have the same name on the
client as on the server, but mail for server user 'hurkle' should be
delivered to client user 'happy'.
+
+.PP
+\fBNote\fP that \fBfetchmail,\fP until version 6.3.4, did NOT allow full
+user@domain specifications here, these would never match.
+\fIFetchmail\fP 6.3.5 and newer support user@domain specifications on
+the left-hand side of a user mapping.
+
.PP
Here's an example of another kind of multidrop connection:
+.IP
.nf
- poll pop.provider.net localdomains loonytoons.org toons.org:
- user maildrop with pass secret1 to * here
+poll pop.provider.net localdomains loonytoons.org toons.org
+ envelope X-Envelope-To
+ user maildrop with pass secret1 to * here
.fi
+.PP
This also says that the mailbox of account 'maildrop' on the server is
-a multi-drop box. It tells fetchmail that any address in the
+a multidrop box. It tells fetchmail that any address in the
loonytoons.org or toons.org domains (including sub-domain addresses like
\&'joe@daffy.loonytoons.org') should be passed through to the local SMTP
listener without modification. Be careful of mail loops if you do this!
+
.PP
Here's an example configuration using ssh and the plugin option. The
queries are made directly on the stdin and stdout of imapd via ssh.
Note that in this setup, IMAP authentication can be skipped.
+.IP
.nf
poll mailhost.net with proto imap:
- plugin "ssh %h /usr/sbin/imapd" auth ssh;
- user esr is esr here
+ plugin "ssh %h /usr/sbin/imapd" auth ssh;
+ user esr is esr here
.fi
.SH THE USE AND ABUSE OF MULTIDROP MAILBOXES
in order to reroute mail properly.
.PP
Sometimes
-.I fetchmail
+\fBfetchmail\fP
can deduce the envelope address. If the mailserver MTA is
-.I sendmail
+\fBsendmail\fP
and the item of mail had just one recipient, the MTA will have written
a 'by/for' clause that gives the envelope addressee into its Received
header. But this doesn't work reliably for other MTAs, nor if there is
-more than one recipient. By default, \fIfetchmail\fR looks for
+more than one recipient. By default, \fBfetchmail\fP looks for
envelope addresses in these lines; you can restore this default with
--E "Received" or \&'envelope Received'.
+\&\-E "Received" or 'envelope Received'.
.PP
-.B As a better alternative,
+\fBAs a better alternative,\fP
some SMTP listeners and/or mail servers insert a header
in each message containing a copy of the envelope addresses. This
-header (when it exists) is often 'X-Original-To', 'Delivered-To' or
-'X-Envelope-To'. Fetchmail's assumption about this can be changed with
-the -E or 'envelope' option. Note that writing an envelope header of
+header (when it exists) is often 'X\-Original\-To', 'Delivered\-To' or
+\&'X\-Envelope\-To'. Fetchmail's assumption about this can be changed with
+the \-E or 'envelope' option. Note that writing an envelope header of
this kind exposes the names of recipients (including blind-copy
recipients) to all receivers of the messages, so the upstream must store
one copy of the message per recipient to avoid becoming a privacy problem.
.PP
-Postfix, since version 2.0, writes an X-Original-To: header which
+Postfix, since version 2.0, writes an X\-Original\-To: header which
contains a copy of the envelope as it was received.
.PP
-Qmail and Postfix generally write a 'Delivered-To' header upon
+Qmail and Postfix generally write a 'Delivered\-To' header upon
delivering the message to the mail spool and use it to avoid mail loops.
Qmail virtual domains however will prefix the user name with a string
that normally matches the user's domain. To remove this prefix you can
-use the -Q or 'qvirtual' option.
+use the \-Q or 'qvirtual' option.
.PP
Sometimes, unfortunately, neither of these methods works. That is the
point when you should contact your ISP and ask them to provide such an
In particular, mailing-list software often ships mail with only
the list broadcast address in the To header.
.PP
-.B Note that a future version of fetchmail may remove To/Cc parsing!
+\fBNote that a future version of \fBfetchmail\fP may remove To/Cc parsing!\fP
.PP
When
-.I fetchmail
+\fBfetchmail\fP
cannot deduce a recipient address that is local, and the intended
recipient address was anyone other than fetchmail's invoking user,
-.B mail will get lost.
+\fBmail will get lost.\fP
This is what makes the multidrop feature risky without proper envelope
information.
.PP
A related problem is that when you blind-copy a mail message, the Bcc
-information is carried \fIonly\fR as envelope address (it's removed from
+information is carried \fIonly\fP as envelope address (it's removed from
the headers by the sending mail server, so fetchmail can see it only if
-there is an X-Envelope-To header). Thus, blind-copying to someone who
+there is an X\-Envelope\-To header). Thus, blind-copying to someone who
gets mail over a fetchmail multidrop link will fail unless the the
-mailserver host routinely writes X-Envelope-To or an equivalent header
+mailserver host routinely writes X\-Envelope\-To or an equivalent header
into messages in your maildrop.
.PP
\fBIn conclusion, mailing lists and Bcc'd mail can only work if the
-server you're fetching from (1) stores one copy of the message per
-recipient in \fBIyour\fP domain and (2) records the envelope
-information in a special header (X-Original-To, Delivered-To,
-X-Envelope-To).\fR
+server you're fetching from\fP
+.IP (1)
+\fBstores one copy of the message per recipient in your domain and\fP
+.IP (2)
+\fBrecords the envelope information in a special header (X\-Original\-To,
+Delivered\-To, X\-Envelope\-To).\fP
.SS Good Ways To Use Multidrop Mailboxes
Multiple local names can be used to administer a mailing list from the
-client side of a \fIfetchmail\fR collection. Suppose your name is
+client side of a \fBfetchmail\fP collection. Suppose your name is
\&'esr', and you want to both pick up your own mail and maintain a mailing
list called (say) "fetchmail-friends", and you want to keep the alias
list on your client machine.
.PP
-On your server, you can alias \&'fetchmail-friends' to 'esr'; then, in
-your \fI.fetchmailrc\fR, declare \&'to esr fetchmail-friends here'.
-Then, when mail including 'fetchmail-friends' as a local address
+On your server, you can alias 'fetchmail\-friends' to 'esr'; then, in
+your \fI.fetchmailrc\fP, declare 'to esr fetchmail\-friends here'.
+Then, when mail including 'fetchmail\-friends' as a local address
gets fetched, the list name will be appended to the list of
recipients your SMTP listener sees. Therefore it will undergo alias
expansion locally. Be sure to include 'esr' in the local alias
-expansion of fetchmail-friends, or you'll never see mail sent only to
+expansion of fetchmail\-friends, or you'll never see mail sent only to
the list. Also be sure that your listener has the "me-too" option set
-(sendmail's -oXm command-line option or OXm declaration) so your name
+(sendmail's \-oXm command-line option or OXm declaration) so your name
isn't removed from alias expansions in messages you send.
.PP
This trick is not without its problems, however. You'll begin to see
this when a message comes in that is addressed only to a mailing list
-you do \fInot\fR have declared as a local name. Each such message
-will feature an 'X-Fetchmail-Warning' header which is generated
+you do \fInot\fP have declared as a local name. Each such message
+will feature an 'X\-Fetchmail\-Warning' header which is generated
because fetchmail cannot find a valid local name in the recipient
addresses. Such messages default (as was described above) to being
-sent to the local user running
-.IR fetchmail ,
-but the program has no way to know that that's actually the right thing.
+sent to the local user running \fBfetchmail\fP, but the program has no
+way to know that that's actually the right thing.
.SS Bad Ways To Abuse Multidrop Mailboxes
Multidrop mailboxes and
-.I fetchmail
+\fBfetchmail\fP
serving multiple users in daemon mode do not mix. The problem, again, is
mail from mailing lists, which typically does not have an individual
recipient address on it. Unless
-.I fetchmail
+\fBfetchmail\fP
can deduce an envelope address, such mail will only go to the account
running fetchmail (probably root). Also, blind-copied users are very
likely never to see their mail at all.
.PP
If you're tempted to use
-.I fetchmail
+\fBfetchmail\fP
to retrieve mail for multiple users from a single mail drop via POP or
IMAP, think again (and reread the section on header and envelope
addresses above). It would be smarter to just let the mail sit in the
frequently than the mailserver's expiry period). If you can't arrange
this, try setting up a UUCP feed.
.PP
-If you absolutely \fImust\fR use multidrop for this purpose, make sure
+If you absolutely \fImust\fP use multidrop for this purpose, make sure
your mailserver writes an envelope-address header that fetchmail can
-see. Otherwise you \fIwill\fR lose mail and it \fIwill\fR come back
+see. Otherwise you \fIwill\fP lose mail and it \fIwill\fP come back
to haunt you.
.SS Speeding Up Multidrop Checking
Normally, when multiple users are declared
-.I fetchmail
+\fBfetchmail\fP
extracts recipient addresses as described above and checks each host
part with DNS to see if it's an alias of the mailserver. If so, the
name mappings described in the "to ... here" declaration are done and
This is a convenient but also slow method. To speed
it up, pre-declare mailserver aliases with 'aka'; these are checked
before DNS lookups are done. If you're certain your aka list contains
-.B all
+\fBall\fP
DNS aliases of the mailserver (and all MX names pointing at it - note
this may change in a future version)
you can declare 'no dns' to suppress DNS lookups entirely and
-\fIonly\fR match against the aka list.
+\fIonly\fP match against the aka list.
+
+.SH SOCKS
+Support for socks4/5 is a \fBcompile time\fP configuration option. Once
+compiled in, fetchmail will always use the socks libraries and
+configuration on your system, there are no run-time switches in
+fetchmail - but you can still configure SOCKS: you can specify which
+SOCKS configuration file is used in the \fBSOCKS_CONF\fP environment
+variable.
+
+For instance, if you wanted to bypass the SOCKS proxy altogether and
+have fetchmail connect directly, you could just pass
+SOCKS_CONF=/dev/null in the environment, for example (add your usual
+command line options - if any - to the end of this line):
+
+.nf
+env SOCKS_CONF=/dev/null fetchmail
+.fi
.SH EXIT CODES
To facilitate the use of
-.I fetchmail
-in shell scripts, an exit code is returned to give an indication
+\fBfetchmail\fP
+in shell scripts, an exit\ status code is returned to give an indication
of what occurred during a given connection.
.PP
The exit codes returned by
-.I fetchmail
+\fBfetchmail\fP
are as follows:
.IP 0
-One or more messages were successfully retrieved (or, if the -c option
+One or more messages were successfully retrieved (or, if the \-c option
was selected, were found waiting but not retrieved).
.IP 1
There was no mail awaiting retrieval. (There may have been old mail still
-on the server but not selected for retrieval.)
+on the server but not selected for retrieval.) If you do not want "no
+mail" to be an error condition (for instance, for cron jobs), use a
+POSIX-compliant shell and add
+
+.nf
+|| [ $? \-eq 1 ]
+.fi
+
+to the end of the fetchmail command line, note that this leaves 0
+untouched, maps 1 to 0, and maps all other codes to 1. See also item #C8
+in the FAQ.
.IP 2
An error was encountered when attempting to open a socket to retrieve
mail. If you don't know what a socket is, don't worry about it --
Some sort of fatal protocol error was detected.
.IP 5
There was a syntax error in the arguments to
-.IR fetchmail .
+\fBfetchmail\fP, or a pre- or post-connect command failed.
.IP 6
The run control file had bad permissions.
.IP 7
There was an error condition reported by the server. Can also
-fire if
-.I fetchmail
-timed out while waiting for the server.
+fire if \fBfetchmail\fP timed out while waiting for the server.
.IP 8
Client-side exclusion error. This means
-.I fetchmail
+\fBfetchmail\fP
either found another copy of itself already running, or failed in such
a way that it isn't sure whether another copy is running.
.IP 9
or some similar text containing the word "lock".
.IP 10
The
-.I fetchmail
+\fBfetchmail\fP
run failed while trying to do an SMTP port open or transaction.
.IP 11
Fatal DNS error. Fetchmail encountered an error while performing
.IP 12
BSMTP batch file could not be opened.
.IP 13
-Poll terminated by a fetch limit (see the --fetchlimit option).
+Poll terminated by a fetch limit (see the \-\-fetchlimit option).
.IP 14
Server busy indication.
-.IP 15
-Server timed out during an IMAP IDLE.
.IP 23
Internal error. You should see a message on standard error with
details.
+.IP "24 - 26, 28, 29"
+These are internal codes and should not appear externally.
.PP
When
-.I fetchmail
-queries more than one host, return status is 0 if \fIany\fR query
+\fBfetchmail\fP
+queries more than one host, return status is 0 if \fIany\fP query
successfully retrieved mail. Otherwise the returned error status is
that of the last host queried.
default run control file
.TP 5
~/.fetchids
-default location of file associating hosts with last message IDs seen
-(used only with newer RFC1939-compliant POP3 servers supporting the
-UIDL command).
+default location of file recording last message UIDs seen per host.
.TP 5
~/.fetchmail.pid
lock file to help prevent concurrent runs (non-root mode).
lock file to help prevent concurrent runs (root mode, systems without /var/run).
.SH ENVIRONMENT
-If the FETCHMAILUSER variable is set, it is used as the name of the
+.IP \fBFETCHMAILHOME\fP
+If this environment variable is set to a valid and
+existing directory name, fetchmail will read $FETCHMAILHOME/fetchmailrc
+(the dot is missing in this case), $FETCHMAILHOME/.fetchids and
+$FETCHMAILHOME/.fetchmail.pid rather than from the user's home
+directory. The .netrc file is always looked for in the the invoking
+user's home directory regardless of FETCHMAILHOME's setting.
+
+.IP \fBFETCHMAILUSER\fP
+If this environment variable is set, it is used as the name of the
calling user (default local name) for purposes such as mailing error
notifications. Otherwise, if either the LOGNAME or USER variable is
correctly set (e.g. the corresponding UID matches the session user ID)
then that name is used as the default local name. Otherwise
-\fBgetpwuid\fR(3) must be able to retrieve a password entry for the
+\fBgetpwuid\fP(3) must be able to retrieve a password entry for the
session ID (this elaborate logic is designed to handle the case of
multiple names per userid gracefully).
-If the environment variable FETCHMAILHOME is set to a valid and
-existing directory name, the .fetchmailrc and .fetchids and
-\&.fetchmail.pid files are put there instead of in the invoking user's
-home directory (and lose the leading dots on their names). The
-\&.netrc file is looked for in the the invoking user's home directory
-regardless of FETCHMAILHOME's setting.
+.IP \fBFETCHMAIL_DISABLE_CBC_IV_COUNTERMEASURE\fP
+(since v6.3.22):
+If this environment variable is set and not empty, fetchmail will disable
+a countermeasure against an SSL CBC IV attack (by setting
+SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS). This is a security risk, but may be
+necessary for connecting to certain non-standards-conforming servers.
+See fetchmail's NEWS file and fetchmail-SA-2012-01.txt for details.
+Earlier fetchmail versions (v6.3.21 and older) used to disable this
+countermeasure, but v6.3.22 no longer does that as a safety precaution.
+
+.IP \fBFETCHMAIL_INCLUDE_DEFAULT_X509_CA_CERTS\fP
+(since v6.3.17):
+If this environment variable is set and not empty, fetchmail will always load
+the default X.509 trusted certificate locations for SSL/TLS CA certificates,
+even if \fB\-\-sslcertfile\fP and \fB\-\-sslcertpath\fP are given. The latter locations take precedence over the system default locations.
+This is useful in case there are broken certificates in the system directories
+and the user has no administrator privileges to remedy the problem.
+
+.IP \fBHOME_ETC\fP
+If the HOME_ETC variable is set, fetchmail will read
+$HOME_ETC/.fetchmailrc instead of ~/.fetchmailrc.
-If the HOME_ETC variable is set, file $HOME_ETC/.fetchmailrc is used
-instead of ~/.fetchmailrc.
+If HOME_ETC and FETCHMAILHOME are both set, HOME_ETC will be ignored.
+
+.IP \fBSOCKS_CONF\fP
+(only if SOCKS support is compiled in) this variable is used by the
+socks library to find out which configuration file it should read. Set
+this to /dev/null to bypass the SOCKS proxy.
.SH SIGNALS
-If a
-.I fetchmail
-daemon is running as root, SIGHUP wakes it up from its sleep phase and
-forces a poll of all non-skipped servers (this is in accordance with
-the usual conventions for system daemons).
+If a \fBfetchmail\fP daemon is running as root, SIGUSR1 wakes it up from its
+sleep phase and forces a poll of all non-skipped servers. For compatibility
+reasons, SIGHUP can also be used in 6.3.X but may not be available in future
+fetchmail versions.
.PP
-If
-.I fetchmail
-is running in daemon mode as non-root, use SIGUSR1 to wake it (this is
-so SIGHUP due to logout can retain the default action of killing it).
+If \fBfetchmail\fP is running in daemon mode as non-root, use SIGUSR1 to wake
+it (this is so SIGHUP due to logout can retain the default action of killing
+it).
.PP
-Running
-.I fetchmail
-in foreground while a background fetchmail is running will do
-whichever of these is appropriate to wake it up.
+Running \fBfetchmail\fP in foreground while a background fetchmail is
+running will do whichever of these is appropriate to wake it up.
-.SH BUGS AND KNOWN PROBLEMS
+.SH BUGS, LIMITATIONS, AND KNOWN PROBLEMS
+.PP
+Please check the \fBNEWS\fP file that shipped with fetchmail for more
+known bugs than those listed here.
+.PP
+Fetchmail cannot handle user names that contain blanks after a "@"
+character, for instance "demonstr@ti on". These are rather uncommon and
+only hurt when using UID-based \-\-keep setups, so the 6.3.X versions of
+fetchmail won't be fixed.
+.PP
+Fetchmail cannot handle configurations where you have multiple accounts
+that use the same server name and the same login. Any user@server
+combination must be unique.
.PP
The assumptions that the DNS and in particular the checkalias options
make are not often sustainable. For instance, it has become uncommon for
zombies accumulate. So either don't deliver to a MDA using plugins or
risk being overrun by an army of undead.
.PP
-The --interface option does not support IPv6 and it is doubtful if it
+The \-\-interface option does not support IPv6 and it is doubtful if it
ever will, since there is no portable way to query interface IPv6
addresses.
.PP
quoting and embedded comments are likely to confuse it.
.PP
In a message with multiple envelope headers, only the last one
-processed will be visible to fetchmail. To get around this, use a
-mailserver-side filter that consolidates the contents of all envelope
-headers into a single one (procmail, mailagent, or maildrop can be
-programmed to do this fairly easily).
+processed will be visible to fetchmail.
.PP
Use of some of these protocols requires that the program send
unencrypted passwords over the TCP/IP connection to the mailserver.
This creates a risk that name/password pairs might be snaffled with a
packet sniffer or more sophisticated monitoring software. Under Linux
-and FreeBSD, the --interface option can be used to restrict polling to
+and FreeBSD, the \-\-interface option can be used to restrict polling to
availability of a specific interface device with a specific local or
remote IP address, but snooping is still possible if (a) either host
has a network device that can be opened in promiscuous mode, or (b)
the intervening network link can be tapped. We recommend the use of
-.IR ssh (1)
+.BR ssh (1)
tunnelling to not only shroud your passwords but encrypt the entire
conversation.
.PP
spam bounces requires that port 25 of localhost be available for sending
mail via SMTP.
.PP
-If you modify a
-.I ~/.fetchmailrc
-while a background instance is running and break the syntax, the
-background instance will die silently. Unfortunately, it can't
-die noisily because we don't yet know whether syslog should be enabled.
-On some systems, fetchmail dies quietly even if there is no syntax
-error; this seems to have something to do with buggy terminal ioctl
-code in the kernel.
+If you modify \fI~/.fetchmailrc\fP while a background instance is
+running and break the syntax, the background instance will die silently.
+Unfortunately, it can't die noisily because we don't yet know whether
+syslog should be enabled. On some systems, fetchmail dies quietly even
+if there is no syntax error; this seems to have something to do with
+buggy terminal ioctl code in the kernel.
.PP
-The -f - option (reading a configuration from stdin) is incompatible
+The \-f\~\- option (reading a configuration from stdin) is incompatible
with the plugin option.
.PP
The 'principal' option only handles Kerberos IV, not V.
.PP
+Interactively entered passwords are truncated after 63 characters. If
+you really need to use a longer password, you will have to use a
+configuration file.
+.PP
+A backslash as the last character of a configuration file will be
+flagged as a syntax error rather than ignored.
+.PP
+The BSMTP error handling is virtually nonexistent and may leave broken
+messages behind.
+.PP
Send comments, bug reports, gripes, and the like to the
-fetchmail-devel list <fetchmail-devel@lists.berlios.de>. An HTML FAQ is
-available at the fetchmail home page; surf to
-http://fetchmail.berlios.de/ or do a WWW search for pages with
-\&'fetchmail' in their titles.
+.MTO "fetchmail-devel@lists.berlios.de" "fetchmail-devel list"
+
+.PP
+An
+.URL "http://fetchmail.berlios.de/fetchmail-FAQ.html" "HTML FAQ"
+is available at the fetchmail home page, it should also accompany your
+installation.
.SH AUTHOR
-Eric S. Raymond <esr@snark.thyrsus.com>. Too many other people to
-name here have contributed code and patches.
-This program is descended from and replaces
-.IR popclient ,
-by Carl Harris <ceharris@mal.com>; the internals have become quite different,
-but some of its interface design is directly traceable to that
-ancestral program.
+Fetchmail is currently maintained by Matthias Andree and Rob Funk with
+major assistance from Sunil Shetye (for code) and Rob MacGregor (for the
+mailing lists).
.PP
-This manual page has been improved by R.\ Hannes Beinert.
+Most of the code is from
+.MTO esr@snark.thyrsus.com "Eric S. Raymond"
+\&. Too many other people to name here have contributed code and patches.
+.PP
+This program is descended from and replaces
+.BR popclient ,
+by
+.MTO "ceharris@mal.com" "Carl Harris"
+\&; the internals have become quite different, but some of its interface
+design is directly traceable to that ancestral program.
.PP
-Fetchmail is currently maintained by Matthias Andree and Rob Funk.
+This manual page has been improved by Matthias Andree, R.\ Hannes
+Beinert, and H\['e]ctor Garc\['i]a.
.SH SEE ALSO
-mutt(1), elm(1), mail(1), sendmail(8), popd(8), imapd(8), netrc(5)
+.PP
+.BR README ,
+.BR README.SSL ,
+.BR README.SSL-SERVER ,
+.URL "http://www.fetchmail.info/fetchmail-FAQ.html" "The Fetchmail FAQ" ,
+.BR mutt (1),
+.BR elm (1),
+.BR mail (1),
+.BR sendmail (8),
+.BR popd (8),
+.BR imapd (8),
+.BR netrc (5).
+
+.PP
+.URL "http://fetchmail.berlios.de/" "The fetchmail home page."
+
+.PP
+.URL "http://www.courier-mta.org/maildrop/" "The maildrop home page."
+
.SH APPLICABLE STANDARDS
+.PP
+Note that this list is just a collection of references and not a
+statement as to the actual protocol conformance or requirements in
+fetchmail.
.TP 5
SMTP/ESMTP:
-RFC 821, RFC2821, RFC 1869, RFC 1652, RFC 1870, RFC 1983, RFC 1985,
+RFC 821, RFC 2821, RFC 1869, RFC 1652, RFC 1870, RFC 1983, RFC 1985,
RFC 2554.
.TP 5
mail:
-RFC 822, RFC2822, RFC 1123, RFC 1892, RFC 1894.
+RFC 822, RFC 2822, RFC 1123, RFC 1892, RFC 1894.
.TP 5
POP2:
RFC 937
.TP 5
POP3:
-RFC 1081, RFC 1225, RFC 1460, RFC 1725, RFC1734, RFC 1939, RFC 1957,
-RFC2195, RFC 2449.
+RFC 1081, RFC 1225, RFC 1460, RFC 1725, RFC 1734, RFC 1939, RFC 1957,
+RFC 2195, RFC 2449.
.TP 5
APOP:
-RFC 1460, RFC 1725, RFC 1939.
+RFC 1939.
.TP 5
RPOP:
RFC 1081, RFC 1225.
RFC 2033.
.TP 5
GSSAPI:
-RFC 1508.
+RFC 1508, RFC 1734,
+.URL http://www.iana.org/assignments/gssapi-service-names/ "Generic Security Service Application Program Interface (GSSAPI)/Kerberos/Simple Authentication and Security Layer (SASL) Service Names" .
.TP 5
TLS:
RFC 2595.
projects / ~andy / fetchmail / blobdiff