- fetchmail README
+fetchmail README
+================
-fetchmail is a full-featured, robust, well-documented POP2, POP3,
-APOP, and IMAP batch mail retrieval/forwarding utility intended to be
-used over on-demand TCP/IP links (such as SLIP or PPP connections).
-It retrieves mail from remote mail servers and forwards it to your
-local (client) machine's delivery system, so it can then be be read by
-normal mail user agents such as elm(1) or Mail(1).
+Introduction
+------------
-The fetchmail code was developed under Linux, but should be readily
-portable to other Unix variants (it uses GNU autoconf). It has also
-been ported to QNX; to build under QNX, see the header comments in the
-Makefile.
+Fetchmail is a free, full-featured, robust, well-documented remote mail
+retrieval and forwarding utility intended to be used over on-demand TCP/IP
+links (such as SLIP or PPP connections). It retrieves mail from remote mail
+servers and forwards it to your local (client) machine's delivery system, so it
+can then be be read by normal mail user agents such as mutt(1), elm(1) or
+Mail(1).
-The fetchmail program was originally authored (under the name
-popclient) by Carl Harris <ceharris@mal.com>. Eric S. Raymond,
-<esr@thyrsus.com> took over development in June 1996 and subsequently
-renamed the program `fetchmail' to reflect the addition of IMAP
-support. See the distribution files NEWS for detailed information on
-recent changes and NOTES for design notes.
+Fetchmail supports all standard mail-retrieval protocols in use on the
+Internet: POP3 (including some variants such as RPOP, APOP, KPOP), IMAP4rev1
+(also IMAP4, IMAP2bis), POP2, IMAP4, ETRN, and ODMR. On the output side,
+fetchmail supports ESMTP/SMTP, LMTP, and invocation of a local delivery agent.
-Before accepting responsibility for the popclient sources from Carl, I
-had investigated and used and tinkered with every other UNIX
-remote-mail forwarder I could find, including fetchpop1.9,
-PopTart-0.9.3, get-mail, gwpop, pimp-1.0, pop-perl5-1.2, popc,
-popmail-1.6 and upop. I learned from all of them, and fetchmail is a
-carefully-thought-out attempt to render obsolete every other program
-in its class.
+Fetchmail also fully supports authentication via GSSAPI, Kerberos 4 and 5,
+RFC1938 one-time passwords, Compuserve's POP3 with RPA, Microsoft's NTLM, Demon
+Internet's SDPS, or CRAM-MD5 authentication a la RFC2195.
-The fetchmail code appears to be stable and free of bugs affecting
-normal operation (that is, retrieving from POP3 or IMAP and forwarding
-via SMTP to sendmail). It will probably undergo substantial change
-only if and when support for a new retrieval protocol or authentication
-is added.
+Fetchmail supports end-to-end encryption with OpenSSL, do read README.SSL for
+details on fetchmail's configuration and README.SSL-SERVER for server-side
+requirements. NOTE! To be compatible with earlier releases, fetchmail 6.4
+default behaviour is more relaxed than dictated by recommendations - while it
+does away with SSLv2, only negotiates SSLv3 if forced to, it will by default
+still negotiate TLS v1.0.
-Here are fetchmail's main features. Those unique to fetchmail are marked
-with **.
+Portability
+-----------
- * **POP2, POP3, **APOP, **IMAP support.
+The fetchmail code was developed under Linux, but has also been extensively
+tested under the BSD variants, AIX, HP-UX versions 9 and 10, SunOS, Solaris,
+NEXTSTEP, OSF 3.2, IRIX, and Rhapsody once upon a time.
- ** Support for Kerberos user authentication.
+The current maintainer does not have access to these systems, and assumes that
+the system is at least Single-Unix-Specification V3 compatible, and that
+will also require a C99 compiler. A further requirement is that
+either realpath() permits its 2nd argument to be NULL for auto-allocation,
+or that otherwise PATH_MAX be defined.
- ** Host is auto-probed for a working server if no protocol is
- specified for the connection. Thus you don't need to know
- what servers are running on your mail host in advance; the
- verbose option will tell you which one succeeds.
+Fetchmail should be able to be compiled with C99, C11, C++98, C++03,
+C++11, C++14 compilers, but not C++17 because the "register" keyword is
+used in some parts of the code.
- ** Delivery via via SMTP to the client machine's port 25. This
- means the retrieved mail automatically goes to the system
- default MDA as if it were normal sender-initiated SMTP mail.
+Future fetchmail releases will require modern language features such as
+"long long" and others, so this release is the last to support C89.
- ** Timeout if server connection is dropped.
+Further reading
+---------------
- ** Support for retrieving and forwarding from multi-drop mailboxes
- that is guaranteed not to cause mail loops.
+The INSTALL file describes how to configure and install fetchmail.
- * Easy control via command line or free-format run control file.
+See the distribution files FEATURES for a full list of features, NEWS for
+detailed information on recent changes, NOTES for design notes, and TODO for
+a list of things that still need doing. If you want to hack on this code,
+a list of known bugs and to-do items can be found in the file todo.html.
- * Daemon mode -- fetchmail can be run in background to poll
- one or more hosts at a specified interval.
+Status, source code
+-------------------
- * From:, To:, Cc:, and Reply-To: headers are rewritten so that
- usernames relative to the fetchmail host become fully-qualified
- Internet addresses. This enables replies to work correctly.
- (Would be unique to fetchmail if I hadn't added it to fetchpop.)
+The fetchmail code appears to be stable and free of bugs affecting normal
+operation (that is, retrieving from POP3 or IMAP in single-drop mode and
+forwarding via SMTP to a local mail transfer agent).
- * Strict conformance to relevant RFCs and good debugging options.
- You could use fetchmail to test and debug server implementatations.
+You can get the code from the fetchmail home page:
- * Carefully written, comprehensive and up-to-date man page describing
- not only modes of operation but also (**) how to diagnose the most
- common kinds of problems and what to do about deficient servers
+ https://www.fetchmail.info/
+ https://fetchmail.sourceforge.io/
- * Rugged, simple, and well-tested code -- the author relies on it
- every day and it has never lost mail, not even in experimental
- versions.
-
- * Large user community -- fetchmail has inherited a significant
- user base from Carl Harris's popclient community. This means
- feedback is rapid, bugs get found and fixed rapidly.
-
-You can easily fetch the latest version of fetchmail via FTP from:
-
- ftp://ftp.ccil.org/pub/esr/fetchmail-2.0.tar.gz
-
-Or you can get it from Eric's home page:
-
- http://www.ccil.org/~esr
-
-Just chase the link to Eric's Freeware Collection. Besides fetchmail, it
-includes a tasty selection of Web authoring tools, programmer's aids,
-graphics libraries, compilers for bizarre languages, games, and
-miscellaneous interesting hacks. Enjoy!
-
- -- esr
+Enjoy!
+ -- esr, ma
projects / ~andy / fetchmail / blobdiff