fetchmail - [fork] set imap idle timeout to 600s, some servers don't follow rfc recommendations

	Commit message (Expand)	Author	Age	Files	Lines
*	Send notification and wedge the connection on too many timeouts.	Eric S. Raymond	1998-11-20	1	-1/+3
*	Now we can use --limit with daemon mode.	Eric S. Raymond	1998-10-16	1	-0/+3
*	Initial revision	Eric S. Raymond	1996-12-17	1	-0/+12

.\" For license terms, see the file COPYING in this directory. .TH fetchmail LOCAL .SH NAME fetchmail \- fetch mail from a POP or IMAP server .SH SYNOPSIS .B fetchmail [\fI options \fR] \fI [mailserver...]\fR .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 \fIelm\fR(1) or \fIMail\fR(1). The \fBfetchmail\fR utility can be run in a daemon mode to repeatedly poll one or more systems at a specified interval. .PP The .I fetchmail program can gather mail from servers supporting any of the common mail-retrieval protocols: POP2 (as specified in RFC 937), POP3 (RFC 1939), IMAP2bis (as implemented by the 4.4BSD imapd program), and IMAP4 (as specified by RFC 1730). It can use (but does not require) the LAST facility removed from later POP3 versions. .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. .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. 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, or \fIqmail\fR). All the delivery-control mechanisms (such as \fI.forward\fR files) normally available through your system MDA will therefore work. .PP The behavior of .I fetchmail is controlled by command-line options and a run control file, \fI~/.fetchmailrc\fR, the syntax of which we describe below. Command-line options override .I ~/.fetchmailrc declarations. .PP To facilitate the use of .I fetchmail In scripts, pipelines, etc., it returns an appropriate exit code upon termination -- see EXIT CODES below. .SH OPTIONS The following options modify the behavior of \fIfetchmail\fR. It is seldom necessary to specify any of these once you have a working \fI.fetchmailrc\fR file set up. .TP .B \-a, --all Retrieve both old (seen) and new messages from the mailserver. The default is to fetch only messages the server has not marked seen. Note that POP2 retrieval behaves as though --all is always on (see RETRIEVAL FAILURE MODES below). .TP .B \-l, --limit Takes a maximum octet size argument. Messages larger than this size will not be fetched, not be marked seen, and will be left on the server (in foreground sessions, the progress messages will note that they are "oversized"). The --all option overrides this one. This option is intended for those need to strictly control fetch time in interactive mode. It may not be used with daemon mode, as users would never receive a notification that messages were waiting. .TP .B \-S host, --smtphost host Specify a host to forward mail to (other than localhost). .TP .B \-m, \--mda You can force mail to be passed to an MDA directly (rather than forwarded to port 25) with the -mda or -m option. If \fIfetchmail\fR is running as root, it sets its userid to that of the target user while delivering mail through an MDA. Some possible MDAs are "/usr/sbin/sendmail -oem", "/usr/lib/sendmail -oem", "/usr/bin/formail", and "/usr/bin/deliver". Local delivery addresses will be inserted into the MDA command wherever you place a %s. Do \fInot\fR use an MDA like "sendmail -oem -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. .TP .B \-F, --flush POP3/IMAP only. Delete old (previously retrieved) messages from the mailserver before retrieving new messages. .TP .B \-c, --check Return a status code to indicate whether there is mail waiting, without actually fetching or deleting mail (see EXIT CODES below). This option doesn't play well with queries to multiple sites, and is ignored in daemon mode. It's also prone to false positives if you leave read but undeleted mail in your server mailbox. .TP .B \-f pathname, --fetchmailrc pathname Specify a non-default name for the .I .fetchmailrc run control file. .TP .B \-i pathname, --idfile pathname Specify an alternate name for the .fetchids file used to save POP3 UIDs. .TP .B \-k, --keep 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. .TP .B \-K, --kill 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 \fBnokill\fR in your \fI.fetchmailrc\fR. .TP .B \-p, \--protocol proto Specify the protocol to used when communicating with the remote mailserver. If no protocol is specified, .I fetchmail will try each of the supported protocols in turn, terminating after any successful attempt. .I proto may be one of the following: .RS .IP IMAP IMAP2bis, a compatible subset of IMAP4. .IP POP2 Post Office Protocol 2 .IP POP3 Post Office Protocol 3 .IP APOP Use POP3 with MD5 authentication. .IP KPOP Use POP3 with Kerberos authentication on port 1109. .RE .TP .B \-P, --port The option permits you to specify a TCP/IP port to connect on. This option will seldom be necessary as all the supported protocols have well-established default port numbers. .TP .B \-A, --auth This option permits you to specify an authentication type (see USER AUTHENTICATION below for details). The possible values are \&`\fBpassword\fR' and `\fBkerberos\fR'. This option is provided primarily for developers; choosing KPOP protocol automatically selects Kerberos authentication, and all other alternatives use ordinary password authentication (though APOP uses a generated one-time key as the password). .TP .B \-r folder, --remote folder Causes a specified non-default mail folder on the mailserver to be retrieved. The syntax of the folder name is server dependent, as is the default behavior when no folder is specified. This option is not available under POP3. .TP .B \-s, --silent Silent mode. Suppresses all progress/status messages that are normally echoed to standard error during a fetch. The --verbose option overrides this. .TP .B \-v, --verbose Verbose mode. All control messages passed between .I fetchmail and the mailserver are echoed to stderr. Overrides --silent. .TP .B \-u name, --username name 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 .I fetchmail. See USER AUTHENTICATION below for a complete description. .TP .B \-n, --norewrite 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.) .TP .B -b, --batchlimit 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). While \fBsendmail\fR(8) normally initiates delivery of a message immediately after receiving the message terminator, some SMTP listeners are not so prompt. MTAs like \fIqmail\fR(8) and \fsmail\fR(8) will wait till the delivery socket is shut down to deliver. This may produce annoying delays when .IR fetchmail (8) is processing very large batches. Setting the batch limit to some nonzero size will prevent these delays. .TP .B \-V, --version Displays the version information for your copy of .I fetchmail. No mail fetch is performed. Instead, for each server specified, all 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. .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 server in your .I ~/.fetchmailrc file will be queried. .SH USER AUTHENTICATION Normal user authentication in .I fetchmail is very much like the authentication mechanism of .I 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 .I 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 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: .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. .PP On mailservers that do not provide ordinary user accounts, your user-id and 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. .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. .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\fR) it will try to get a Kerberos ticket from the mailserver at the start of each query. .SH DAEMON MODE The .B --daemon or .B -d 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 .IP 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. .PP Only one daemon process is permitted per user; in daemon mode, .I fetchmail makes a per-user lockfile to guarantee this. The option .B --quit will kill a running daemon process. Otherwise, calling fetchmail with a daemon in the background sends a wakeup signal to the daemon, forcing it to poll mailservers immediately. .PP The .B -t or .B --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. .PP The .B -L or .B --logfile option allows you to redirect status messages emitted while in daemon mode 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. .PP The .B \-N or --nodetach option suppresses detachment of the daemon process from its control terminal. This is primarily useful for debugging. .PP Note that while running in daemon mode, transient errors (such as DNS failures or sendmail delivery refusals) effectively force the fetchall option on for the duration of the next polling cycle. This is a robustness feature. It means that if a message is fetched (and thus marked seen by the mailserver) but not delivered locally due to some transient error, it will be re-fetched during the next poll cycle. .SH RETRIEVAL FAILURE MODES The protocols \fIfetchmail\fR 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 has acknowledged to \fIfetchmail\fR that the message has been accepted for delivery. When forwarding to an MDA, however, there is more possibility of error (because there's no way for fetchmail to get a reliable positive acknowledgement from the MDA). .PP The normal mode of \fIfetchmail\fR 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 server are being fetched (and deleted) even when you don't specify --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 must treat all messages as new all the time. But POP2 is obsolete, so this is unlikely. .PP Under POP3, blame RFC1725. That version of the POP3 protocol specification removed the LAST command, and some POP servers follow it (you can verify this by invoking \fIfetchmail -v\fR to the mailserver and watching the response to LAST early in the query). The \fIfetchmail\fR code tries to compensate by using POP3's UID feature, storing the identifiers of messages seen in each session until the next session, in the \fI.fetchids\fR file. But this doesn't track messages seen with other clients, or read directly with a mailer on the host but not deleted afterward. A better solution would be to switch to IMAP. .PP Another 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 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. The only real fix for this problem is to switch to IMAP. .PP The IMAP code uses the presence or absence of the server flag \eSeen to decide whether or not a message is new. Under Unix, it counts on your IMAP server to notice the BSD-style Status flags set by mail user agents and set the \eSeen flag from them when appropriate. All Unix IMAP servers we know of do 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 will be both undeleted and marked old. .SH SPAM FILTERING Newer versions of .I sendmail allow administrators to set up `spam filters' that block unsolicited email from specified domains. A MAIL FROM line that triggers this feature will elicit an SMTP response with an error code of 571. The .I fetchmail code recognizes this error and discards the message. This is the .I only circumstance under which fetchmail ever discards mail. .SH THE RUN CONTROL FILE The preferred way to set up fetchmail (and the only way if you want to avoid specifying passwords each time it runs) is to write a \&\fI.fetchmailrc\fR file in your home directory. To protect the security of your passwords, your \fI~/.fetchmailrc\fR may not have more than 600 (u=rw,g=,o=) permissions; .I fetchmail will complain and exit otherwise. .PP You may read the \fI.fetchmailrc\fR file as a list of commands to be executed when .I fetchmail is called with no arguments. .PP Comments begin with a '#' and extend through the end of the line. Otherwise the file consists of a series of free-format server entries or global option statement. .PP Any amount of whitespace separates keywords, tokens, or strings in server entries, but is otherwise ignored (except that whitespace enclosed in double quotes is treated as part of the string). Keywords and identifiers are case sensitive. You may use standard C-style escapes (\en, \et, \eb, octal, and hex) to embed non-printable characters or string delimiters in strings. When there is a conflict between the command-line arguments and the arguments in this file, the command-line arguments take precedence. .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. .PP The `poll' verb tells fetchmail to query this host when it is run with no arguments. The `skip' verb tells .I fetchmail 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.) .PP Legal server options are: protocol (or proto) port authenticate (or auth) timeout envelope aka Legal user options are username (or user) is to password (or pass) remotefolder (or remote) smtphost (or smtp) mda keep flush fetchall rewrite nokeep noflush nofetchall norewrite .PP All options correspond to the obvious command-line arguments except four: `aka', `is', `to', `password', and `envelope'. .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. .PP The `envelope' 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. .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. .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 To, Cc, and Bcc headers. .PP When there is more than one local name (or name mapping) the \fIfetchmail\fR code does look at the To, Cc, and Bcc headers of retrieved mail. When a declared mailserver username is recognized, its local mapping is added to the list of local recipients. If \fIfetchmail\fR cannot recognize any mailserver usernames, the default recipient is the calling user. .PP The \fBpassword\fR option requires a string argument, which is the password to be used with the entry's server. .PP The \fBaliases\fR option declares names that are recognized as OK for local delivery. Your local name is automatically one of these; the aliases directive can be used to declare others. .PP Legal protocol identifiers are auto (or AUTO) pop2 (or POP2) pop3 (or POP3) imap (or IMAP) apop (or APOP) kpop (or KPOP) .PP Legal authentication types are `password' or `kerberos'. The former specifies authentication by normal transmission of a password (the password may be plaintext or subject to protocol-specific encryption as in APOP); the second tells \fIfetchmail\fR to try to get a Kerberos ticket at the start of each query instead, and send an arbitrary string as the password. .PP Specifying `kpop' sets POP3 protocol over port 1109 with Kerberos authentication. These defaults may be overridden by later options. .PP You can use the noise keywords `and', `with', `has', `wants', and `options' anywhere in an entry to make it resemble English. They're ignored, but but can make entries much easier to read at a glance. The punctuation characters ':', ';' and ',' are also ignored. .PP The words `here' and `there' have useful English-like significance. Normally `user eric is esr' would mean that mail for the remote user `eric' is to be delivered to `esr', but you can make this clearer by saying `user eric there is esr here', or reverse it by saying `user esr here is eric there' .PP For backward compatibility, the word `server' is a synonym for `poll'. .PP There are currently two valid global option statements; \&`set batchlimit = ' followed by a number and sets the same global specified by the --batchlimit option, and `set logfile = ' followed by a string sets the same global specified by --logfile. In both cases, a command-line option will override. .PP Basic format is: .nf poll SERVERNAME protocol PROTOCOL username NAME password PASSWORD .fi .PP Example: .nf poll pop.provider.net protocol pop3 username jsmith password secret1 .fi .PP Or, using some abbreviations: .nf poll pop.provider.net proto pop3 user jsmith password secret1 .fi .PP Multiple servers may be listed: .nf 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: .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; .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: .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" .fi 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: .nf 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). The `user' keyword leads off a user description, and every user description except optionally the first one must include it. (If the first description lacks the `user' keyword, the name of the invoking user is used.) Here's a contrived example: .nf poll pop.provider.net proto pop3 port 3111 pass gumshoe user jsmith with pass secret1 is smith here user jones with pass secret2 is jjones here .fi This says that the user invoking \fIfetchmail\fR has the same username on pop.provider.net, and password `gumshoe' there. It also associates the local username `smith' with the pop.provider.net username `jsmith' and the local username `jones' with the pop.provider.net username `jjones'. .PP This example is contrived because, in practice, you are very unlikely to be specifying multiple users per server unless running it as root (thus the `pass gumshoe' would try to fetch root's mail on pop-provider.net, which is probably not what you want). In any case, we strongly recommend always having an explicit \&`user' clause when specifying multiple users per mailserver. .PP Here's what a simple retrieval configuration for a multi-drop mailbox looks like: .nf poll pop.provider.net: user maildrop with pass secret1 to golux hurkle=happy snark here .fi 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 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'. .SH THE USE AND ABUSE OF MULTIDROP MAILBOXES Use the multiple-local-recipients feature with caution -- it can bite. The fundamental problem is that by having your server toss several peoples' mail in a box, you may have thrown away potentially vital information about who each piece of mail was actually addressed to (the `envelope address', as opposed to the addresses in the headers). This can't always be deduced from the headers, especially when mailing lists are involved. .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 \&`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' in any of its recipient lines 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 the list!) .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 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. .SS Bad Ways To Abuse Multidrop Mailboxes Multidrop mailboxes and .I fetchmail 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. If you have multiple local names declared, .I fetchmail cannot know which to send it to! It will only go to the account running fetchmail (probably root). .PP Matters are further complicated by the fact that sometimes .I fetchmail \fIcan\fR in fact deduce the envelope address. If the server-side MTA is .I sendmail and the item of mail had just one recipient, the MTA will have written a `for' clause that gives the envelope addressee into its Received header. But this doesn't work for other MTAs, nor if there is more than one recipient. .PP Alternatively, 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-Envelope-To'. Fetchmail's assumption about this can be changed with the `envelope' option. .SH EXIT CODES To facilitate the use of .I fetchmail in shell scripts, an exit code is returned to give an indication of what occurred during a given connection. .PP The exit codes returned by .I fetchmail are as follows: .IP 0 One or more messages were successfully retrieved. .IP 1 There was no mail awaiting retrieval. .IP 2 An error was encountered when attempting to open a socket for the POP connection. If you don't know what a socket is, don't worry about it -- just treat this as an 'unrecoverable error'. .IP 3 The user authentication step failed. This usually means that a bad user-id, password, or APOP id was specified. .IP 4 Some sort of fatal protocol error was detected. .IP 5 There was a syntax error in the arguments to .I fetchmail. .IP 6 The run control file had bad permissions. .IP 7 There was an error condition reported by the server (POP3 only). .IP 8 Exclusion error. This means .I fetchmail 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 The .I fetchmail. run failed while trying to do an SMTP port open or transaction. .IP 10 Internal error. You should see a message on standard error with details. .PP When .I fetchmail queries more than one host, the returned status is that of the last host queried. .SH AUTHOR Eric S. Raymond <esr@snark.thyrsus.com>. .SH BACKWARD COMPATIBILITY This program is descended from and replaces .IR popclient , by Carl Harris <ceharris@mal.com>; the internals are quite different, but some of its interface design is directly traceable to that ancestral program. Some effort has been made to preserve compatibility. .PP If called through a link named `popclient', \fIfetchmail\fR will look in ~/.poprc for its run control file. As long as the file does not use the removed `localfolder' option or `limit' (which now takes a maximum byte size rather than a line count), this will often work. (The new run control file syntax also has to be a little stricter about the order of options than the old, in order to support multiple user desriptions per server; thus you may have to rearrange things a bit.) .SH FILES .TP 5 ~/.fetchmailrc default run control file .TP 5 ~/.fetchids default location of file associating hosts with last message IDs seen (used only with newer RFC1725-compliant POP3 servers supporting the UIDL command). .TP 5 ${TMPDIR}/fetchmail-${USER} lock file to help prevent concurrent runs. .SH ENVIRONMENT For correct initialization, .I fetchmail requires either that both the USER and HOME environment variables are correctly set, or that \fBgetpwuid\fR(3) be able to retrieve a password entry from your user ID. .SH BUGS AND KNOWN PROBLEMS Use of any of the supported protocols other than APOP or KPOP 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. .PP Send comments, bug reports, gripes, and the like to Eric S. Raymond <esr@thyrsus.com>. .SH SEE ALSO elm(1), mail(1), sendmail(8), popd(8), imapd(8); RFC 937, RFC 1081, RFC1176, RFC 1225, RFC 1460, RFC 1725, RFC1939.