Update documentation for 4.61 and some of the preparation tools.
[exim.git] / doc / doc-docbook / spec.xfpt
1 . $Cambridge: exim/doc/doc-docbook/spec.xfpt,v 1.2 2006/04/04 14:03:49 ph10 Exp $
2 .
3 . /////////////////////////////////////////////////////////////////////////////
4 . This is the primary source of the Exim Manual. It is an xfpt document that is
5 . converted into DocBook XML for subsequent conversion into printing and online
6 . formats. The markup used herein is "standard" xfpt markup, with some extras.
7 . The markup is summarized in a file called Markup.txt.
8 . /////////////////////////////////////////////////////////////////////////////
10 .include stdflags
11 .include stdmacs
12 .docbook
13 .book
15 . /////////////////////////////////////////////////////////////////////////////
16 . These definitions set some parameters and save some typing. Remember that
17 . the <bookinfo> element must also be updated for each new edition.
18 . /////////////////////////////////////////////////////////////////////////////
20 .set ACL "access control lists (ACLs)"
21 .set previousversion "4.60"
22 .set version "4.61"
25 . /////////////////////////////////////////////////////////////////////////////
26 . Additional xfpt markup used by this document, over and above the default
27 . provided in the xfpt library.
28 . /////////////////////////////////////////////////////////////////////////////
30 . --- Override the &$ flag to automatically insert a $ with the variable name
32 .flag &$ $& "<varname>$" "</varname>"
34 . --- Short flags for daggers in option headings. They will always be inside
35 . --- an italic string, but we want the daggers to be roman.
37 .flag &!! "</emphasis>&dagger;<emphasis>"
38 .flag &!? "</emphasis>&Dagger;<emphasis>"
40 . --- A macro for an Exim option definition heading, generating a one-line
41 . --- table with four columns.
43 .macro option
44 .oindex "$1"
45 .itable all 0 0 4 8* left 5* center 5* center 6* right
46 .row "&%$1%&" "Use: &'$2'&" "Type: &'$3'&" "Default: &'$4'&"
47 .endtable
48 .endmacro
50 . --- A macro for the common 2-column tables. The width of the first column
51 . --- is suitable for the many tables at the start of the main options chapter;
52 . --- the small number of other 2-column tables override it.
54 .macro table2 190pt 260pt
55 .itable none 0 0 2 $1 left $2 left
56 .endmacro
58 . --- Macros for the concept and option index entries. For a "range" style of
59 . --- entry, use .scindex for the start and .ecindex for the end. The first
60 . --- argument of .scindex and the only argument of .ecindex must be the ID
61 . --- that ties them together.
63 .macro cindex
64 &<indexterm role="concept">&
65 &<primary>&$1&</primary>&
66 .arg 2
67 &<secondary>&$2&</secondary>&
68 .endarg
69 &</indexterm>&
70 .endmacro
72 .macro scindex
73 &<indexterm role="concept" id="$1" class="startofrange">&
74 &<primary>&$2&</primary>&
75 .arg 3
76 &<secondary>&$3&</secondary>&
77 .endarg
78 &</indexterm>&
79 .endmacro
81 .macro ecindex
82 &<indexterm role="concept" startref="$1" class="endofrange"/>&
83 .endmacro
85 .macro oindex
86 &<indexterm role="option">&
87 &<primary>&$1&</primary>&
88 .arg 2
89 &<secondary>&$2&</secondary>&
90 .endarg
91 &</indexterm>&
92 .endmacro
94 .macro index
95 .echo "** Don't use .index; use .cindex or .oindex"
96 .endmacro
97 . ////////////////////////////////////////////////////////////////////////////
100 . ////////////////////////////////////////////////////////////////////////////
101 . The <bookinfo> element is removed from the XML before processing for Ascii
102 . output formats.
103 . ////////////////////////////////////////////////////////////////////////////
105 .literal xml
106 <bookinfo>
107 <title>Specification of the Exim Mail Transfer Agent</title>
108 <titleabbrev>The Exim MTA</titleabbrev>
109 <date>22 March 2006</date>
110 <author><firstname>Philip</firstname><surname>Hazel</surname></author>
111 <authorinitials>PH</authorinitials>
112 <affiliation><orgname>University of Cambridge Computing Service</orgname></affiliation>
113 <address>New Museums Site, Pembroke Street, Cambridge CB2 3QH, England</address>
114 <revhistory><revision>
115 <revnumber>4.61</revnumber>
116 <date>22 March 2006</date>
117 <authorinitials>PH</authorinitials>
118 </revision></revhistory>
119 <copyright><year>2006</year><holder>University of Cambridge</holder></copyright>
120 </bookinfo>
121 .literal off
124 . /////////////////////////////////////////////////////////////////////////////
125 . This chunk of literal XML implements index entries of the form "x, see y" and
126 . "x, see also y". However, the DocBook DTD doesn't allow <indexterm> entries
127 . at the top level, so we have to put the .chapter directive first.
128 . /////////////////////////////////////////////////////////////////////////////
130 .chapter "Introduction"
131 .literal xml
133 <indexterm role="concept">
134 <primary>$1, $2, etc.</primary>
135 <see><emphasis>numerical variables</emphasis></see>
136 </indexterm>
137 <indexterm role="concept">
138 <primary>address</primary>
139 <secondary>rewriting</secondary>
140 <see><emphasis>rewriting</emphasis></see>
141 </indexterm>
142 <indexterm role="concept">
143 <primary>Bounce Address Tag Validation</primary>
144 <see><emphasis>BATV</emphasis></see>
145 </indexterm>
146 <indexterm role="concept">
147 <primary>Client SMTP Authorization</primary>
148 <see><emphasis>CSA</emphasis></see>
149 </indexterm>
150 <indexterm role="concept">
151 <primary>CR character</primary>
152 <see><emphasis>carriage return</emphasis></see>
153 </indexterm>
154 <indexterm role="concept">
155 <primary>CRL</primary>
156 <see><emphasis>certificate revocation list</emphasis></see>
157 </indexterm>
158 <indexterm role="concept">
159 <primary>delivery</primary>
160 <secondary>failure report</secondary>
161 <see><emphasis>bounce message</emphasis></see>
162 </indexterm>
163 <indexterm role="concept">
164 <primary>dialup</primary>
165 <see><emphasis>intermittently connected hosts</emphasis></see>
166 </indexterm>
167 <indexterm role="concept">
168 <primary>exiscan</primary>
169 <see><emphasis>content scanning</emphasis></see>
170 </indexterm>
171 <indexterm role="concept">
172 <primary>failover</primary>
173 <see><emphasis>fallback</emphasis></see>
174 </indexterm>
175 <indexterm role="concept">
176 <primary>fallover</primary>
177 <see><emphasis>fallback</emphasis></see>
178 </indexterm>
179 <indexterm role="concept">
180 <primary>filter</primary>
181 <secondary>Sieve</secondary>
182 <see><emphasis>Sieve filter</emphasis></see>
183 </indexterm>
184 <indexterm role="concept">
185 <primary>ident</primary>
186 <see><emphasis>RFC 1413</emphasis></see>
187 </indexterm>
188 <indexterm role="concept">
189 <primary>LF character</primary>
190 <see><emphasis>linefeed</emphasis></see>
191 </indexterm>
192 <indexterm role="concept">
193 <primary>maximum</primary>
194 <see><emphasis>limit</emphasis></see>
195 </indexterm>
196 <indexterm role="concept">
197 <primary>monitor</primary>
198 <see><emphasis>Exim monitor</emphasis></see>
199 </indexterm>
200 <indexterm role="concept">
201 <primary>no_<emphasis>xxx</emphasis></primary>
202 <see>entry for xxx</see>
203 </indexterm>
204 <indexterm role="concept">
205 <primary>NUL</primary>
206 <see><emphasis>binary zero</emphasis></see>
207 </indexterm>
208 <indexterm role="concept">
209 <primary>passwd file</primary>
210 <see><emphasis>/etc/passwd</emphasis></see>
211 </indexterm>
212 <indexterm role="concept">
213 <primary>process id</primary>
214 <see><emphasis>pid</emphasis></see>
215 </indexterm>
216 <indexterm role="concept">
217 <primary>RBL</primary>
218 <see><emphasis>DNS list</emphasis></see>
219 </indexterm>
220 <indexterm role="concept">
221 <primary>redirection</primary>
222 <see><emphasis>address redirection</emphasis></see>
223 </indexterm>
224 <indexterm role="concept">
225 <primary>return path</primary>
226 <seealso><emphasis>envelope sender</emphasis></seealso>
227 </indexterm>
228 <indexterm role="concept">
229 <primary>scanning</primary>
230 <see><emphasis>content scanning</emphasis></see>
231 </indexterm>
232 <indexterm role="concept">
233 <primary>SSL</primary>
234 <see><emphasis>TLS</emphasis></see>
235 </indexterm>
236 <indexterm role="concept">
237 <primary>string</primary>
238 <secondary>expansion</secondary>
239 <see><emphasis>expansion</emphasis></see>
240 </indexterm>
241 <indexterm role="concept">
242 <primary>top bit</primary>
243 <see><emphasis>8-bit characters</emphasis></see>
244 </indexterm>
245 <indexterm role="concept">
246 <primary>variables</primary>
247 <see><emphasis>expansion, variables</emphasis></see>
248 </indexterm>
249 <indexterm role="concept">
250 <primary>zero, binary</primary>
251 <see><emphasis>binary zero</emphasis></see>
252 </indexterm>
254 .literal off
257 . /////////////////////////////////////////////////////////////////////////////
258 . This is the real start of the first chapter. See the comment above as to why
259 . we can't have the .chapter line here.
260 . chapter "Introduction"
261 . /////////////////////////////////////////////////////////////////////////////
263 Exim is a mail transfer agent (MTA) for hosts that are running Unix or
264 Unix-like operating systems. It was designed on the assumption that it would be
265 run on hosts that are permanently connected to the Internet. However, it can be
266 used on intermittently connected hosts with suitable configuration adjustments.
268 Configuration files currently exist for the following operating systems: AIX,
269 BSD/OS (aka BSDI), Darwin (Mac OS X), DGUX, Dragonfly, FreeBSD, GNU/Hurd,
270 GNU/Linux, HI-OSF (Hitachi), HI-UX, HP-UX, IRIX, MIPS RISCOS, NetBSD, OpenBSD,
271 OpenUNIX, QNX, SCO, SCO SVR4.2 (aka UNIX-SV), Solaris (aka SunOS5), SunOS4,
272 Tru64-Unix (formerly Digital UNIX, formerly DEC-OSF1), Ultrix, and Unixware.
273 Some of these operating systems are no longer current and cannot easily be
274 tested, so the configuration files may no longer work in practice.
276 There are also configuration files for compiling Exim in the Cygwin environment
277 that can be installed on systems running Windows. However, this document does
278 not contain any information about running Exim in the Cygwin environment.
280 The terms and conditions for the use and distribution of Exim are contained in
281 the file &_NOTICE_&. Exim is distributed under the terms of the GNU General
282 Public Licence, a copy of which may be found in the file &_LICENCE_&.
284 The use, supply or promotion of Exim for the purpose of sending bulk,
285 unsolicited electronic mail is incompatible with the basic aims of the program,
286 which revolve around the free provision of a service that enhances the quality
287 of personal communications. The author of Exim regards indiscriminate
288 mass-mailing as an antisocial, irresponsible abuse of the Internet.
290 Exim owes a great deal to Smail 3 and its author, Ron Karr. Without the
291 experience of running and working on the Smail 3 code, I could never have
292 contemplated starting to write a new MTA. Many of the ideas and user interfaces
293 were originally taken from Smail 3, though the actual code of Exim is entirely
294 new, and has developed far beyond the initial concept.
296 Many people, both in Cambridge and around the world, have contributed to the
297 development and the testing of Exim, and to porting it to various operating
298 systems. I am grateful to them all. The distribution now contains a file called
299 &_ACKNOWLEDGMENTS_&, in which I have started recording the names of
300 contributors.
303 .section "Exim documentation"
304 .new
305 .cindex "documentation"
306 This edition of the Exim specification applies to version &version; of Exim.
307 Substantive changes from the &previousversion; edition are marked in some
308 renditions of the document; this paragraph is so marked if the rendition is
309 capable of showing a change indicator.
310 .wen
312 This document is very much a reference manual; it is not a tutorial. The reader
313 is expected to have some familiarity with the SMTP mail transfer protocol and
314 with general Unix system administration. Although there are some discussions
315 and examples in places, the information is mostly organized in a way that makes
316 it easy to look up, rather than in a natural order for sequential reading.
317 Furthermore, the manual aims to cover every aspect of Exim in detail, including
318 a number of rarely-used, special-purpose features that are unlikely to be of
319 very wide interest.
321 .cindex "books about Exim"
322 An &"easier"& discussion of Exim which provides more in-depth explanatory,
323 introductory, and tutorial material can be found in a book entitled &'The Exim
324 SMTP Mail Server'&, published by UIT Cambridge
325 (&url(http://www.uit.co.uk/exim-book/)).
327 This book also contains a chapter that gives a general introduction to SMTP and
328 Internet mail. Inevitably, however, the book is unlikely to be fully up-to-date
329 with the latest release of Exim. (Note that the earlier book about Exim,
330 published by O'Reilly, covers Exim 3, and many things have changed in Exim 4.)
332 .cindex "Debian" "information sources"
333 If you are using a Debian distribution of Exim, you will find information about
334 Debian-specific features in the file
335 .display
336 &_/usr/share/doc/exim4-base/README.Debian_&
337 .endd
338 The command &(man update-exim.conf)& is another source of Debian-specific
339 information.
341 .cindex "&_doc/NewStuff_&"
342 .cindex "&_doc/ChangeLog_&"
343 .cindex "change log"
344 As the program develops, there may be features in newer versions that have not
345 yet made it into this document, which is updated only when the most significant
346 digit of the fractional part of the version number changes. Specifications of
347 new features that are not yet in this manual are placed in the file
348 &_doc/NewStuff_& in the Exim distribution.
350 Some features may be classified as &"experimental"&. These may change
351 incompatibly while they are developing, or even be withdrawn. For this reason,
352 they are not documented in this manual. Information about experimental features
353 can be found in the file &_doc/experimental.txt_&.
355 All changes to the program (whether new features, bug fixes, or other kinds of
356 change) are noted briefly in the file called &_doc/ChangeLog_&.
358 .cindex "&_doc/spec.txt_&"
359 This specification itself is available as an ASCII file in &_doc/spec.txt_& so
360 that it can easily be searched with a text editor. Other files in the &_doc_&
361 directory are:
363 .table2 100pt
364 .row &_OptionLists.txt_& "list of all options in alphabetical order"
365 .row &_dbm.discuss.txt_& "discussion about DBM libraries"
366 .row &_exim.8_& "a man page of Exim's command line options"
367 .row &_experimental.txt_& "documentation of experimental features"
368 .row &_filter.txt_& "specification of the filter language"
369 .row &_pcrepattern.txt_& "specification of PCRE regular expressions"
370 .row &_pcretest.txt_& "specification of the PCRE testing program"
371 .row &_Exim3.upgrade_& "upgrade notes from release 2 to release 3"
372 .row &_Exim4.upgrade_& "upgrade notes from release 3 to release 4"
373 .endtable
375 The main specification and the specification of the filtering language are also
376 available in other formats (HTML, PostScript, PDF, and Texinfo). Section
377 &<<SECTavail>>& below tells you how to get hold of these.
381 .section "FTP and web sites"
382 .cindex "web site"
383 .cindex "FTP site"
384 The primary site for Exim source distributions is currently the University of
385 Cambridge's FTP site, whose contents are described in &'Where to find the Exim
386 distribution'& below. In addition, there is a web site and an FTP site at
387 &%exim.org%&. These are now also hosted at the University of Cambridge. The
388 &%exim.org%& site was previously hosted for a number of years by Energis
389 Squared, formerly Planet Online Ltd, whose support I gratefully acknowledge.
391 .cindex "wiki"
392 .cindex "FAQ"
393 As well as Exim distribution tar files, the Exim web site contains a number of
394 differently formatted versions of the documentation, including the FAQ in both
395 text and HTML formats. The HTML version comes with a keyword-in-context index.
396 A recent addition to the online information is the Exim wiki
397 (&url(http://www.exim.org/eximwiki/)). We hope that this will make it easier
398 for Exim users to contribute examples, tips, and know-how for the benefit of
399 others.
403 .section "Mailing lists"
404 .cindex "mailing lists" "for Exim users"
405 The following are the three main Exim mailing lists:
407 .table2 140pt
408 .row &'exim-users@exim.org'& "general discussion list"
409 .row &'exim-dev@exim.org'& "discussion of bugs, enhancements, etc."
410 .row &'exim-announce@exim.org'& "moderated, low volume announcements list"
411 .endtable
413 You can subscribe to these lists, change your existing subscriptions, and view
414 or search the archives via the mailing lists link on the Exim home page.
415 .cindex "Debian" "mailing list for"
416 If you are using a Debian distribution of Exim, you may wish to subscribe to
417 the Debian-specific mailing list &'pkg-exim4-users@lists.alioth.debian.org'&.
419 .section "Exim training"
420 .cindex "training courses"
421 From time to time (approximately annually at the time of writing), training
422 courses are run by the author of Exim in Cambridge, UK. Details of any
423 forthcoming courses can be found on the web site
424 &url(http://www-tus.csx.cam.ac.uk/courses/exim/).
427 .section "Bug reports"
428 .cindex "bug reports"
429 .cindex "reporting bugs"
430 Reports of obvious bugs should be emailed to &'bugs@exim.org'&. However, if you
431 are unsure whether some behaviour is a bug or not, the best thing to do is to
432 post a message to the &'exim-dev'& mailing list and have it discussed.
436 .section "Where to find the Exim distribution" "SECTavail"
437 .cindex "FTP site"
438 .cindex "distribution" "ftp site"
439 The master ftp site for the Exim distribution is
440 .display
441 &*ftp://ftp.csx.cam.ac.uk/pub/software/email/exim*&
442 .endd
443 This is mirrored by
444 .display
445 &*ftp://ftp.exim.org/pub/exim*&
446 .endd
447 The file references that follow are relative to the &_exim_& directories at
448 these sites. There are now quite a number of independent mirror sites around
449 the world. Those that I know about are listed in the file called &_Mirrors_&.
451 Within the &_exim_& directory there are subdirectories called &_exim3_& (for
452 previous Exim 3 distributions), &_exim4_& (for the latest Exim 4
453 distributions), and &_Testing_& for testing versions. In the &_exim4_&
454 subdirectory, the current release can always be found in files called
455 .display
456 &_exim-n.nn.tar.gz_&
457 &_exim-n.nn.tar.bz2_&
458 .endd
459 where &'n.nn'& is the highest such version number in the directory. The two
460 files contain identical data; the only difference is the type of compression.
461 The &_.bz2_& file is usually a lot smaller than the &_.gz_& file.
463 .cindex "distribution" "signing details"
464 .cindex "distribution" "public key"
465 .cindex "public key for signed distribution"
466 The distributions are currently signed with Philip Hazel's GPG key. The
467 corresponding public key is available from a number of keyservers, and there is
468 also a copy in the file &_Public-Key_&. The signatures for the tar bundles are
469 in:
470 .display
471 &_exim-n.nn.tar.gz.sig_&
472 &_exim-n.nn.tar.bz2.sig_&
473 .endd
474 For each released version, the log of changes is made separately available in a
475 separate file in the directory &_ChangeLogs_& so that it is possible to
476 find out what has changed without having to download the entire distribution.
478 .cindex "documentation" "available formats"
479 The main distribution contains ASCII versions of this specification and other
480 documentation; other formats of the documents are available in separate files
481 inside the &_exim4_& directory of the FTP site:
482 .display
483 &_exim-html-n.nn.tar.gz_&
484 &_exim-pdf-n.nn.tar.gz_&
485 &_exim-postscript-n.nn.tar.gz_&
486 &_exim-texinfo-n.nn.tar.gz_&
487 .endd
488 These tar files contain only the &_doc_& directory, not the complete
489 distribution, and are also available in &_.bz2_& as well as &_.gz_& forms.
490 .cindex "FAQ"
491 The FAQ is available for downloading in two different formats in these files:
492 .display
493 &_exim4/FAQ.txt.gz_&
494 &_exim4/FAQ.html.tar.gz_&
495 .endd
496 The first of these is a single ASCII file that can be searched with a text
497 editor. The second is a directory of HTML files, normally accessed by starting
498 at &_index.html_&. The HTML version of the FAQ (which is also included in the
499 HTML documentation tarbundle) includes a keyword-in-context index, which is
500 often the most convenient way of finding your way around.
503 .section "Wish list"
504 .cindex "wish list"
505 A wish list is maintained, containing ideas for new features that have been
506 submitted. From time to time the file is exported to the ftp site into the file
507 &_exim4/WishList_&. Items are removed from the list if they get implemented.
511 .section "Contributed material"
512 .cindex "contributed material"
513 At the ftp site, there is a directory called &_Contrib_& that contains
514 miscellaneous files contributed to the Exim community by Exim users. There is
515 also a collection of contributed configuration examples in
516 &_exim4/config.samples.tar.gz_&. These samples are referenced from the FAQ.
520 .section "Limitations"
521 .ilist
522 .cindex "limitations of Exim"
523 .cindex "bang paths" "not handled by Exim"
524 Exim is designed for use as an Internet MTA, and therefore handles addresses in
525 RFC 2822 domain format only. It cannot handle UUCP &"bang paths"&, though
526 simple two-component bang paths can be converted by a straightforward rewriting
527 configuration. This restriction does not prevent Exim from being interfaced to
528 UUCP as a transport mechanism, provided that domain addresses are used.
529 .next
530 .cindex "domainless addresses"
531 .cindex "address" "without domain"
532 Exim insists that every address it handles has a domain attached. For incoming
533 local messages, domainless addresses are automatically qualified with a
534 configured domain value. Configuration options specify from which remote
535 systems unqualified addresses are acceptable. These are then qualified on
536 arrival.
537 .next
538 .cindex "transport" "external"
539 .cindex "external transports"
540 The only external transport mechanisms that are currently implemented are SMTP
541 and LMTP over a TCP/IP network (including support for IPv6). However, a pipe
542 transport is available, and there are facilities for writing messages to files
543 and pipes, optionally in &'batched SMTP'& format; these facilities can be used
544 to send messages to other transport mechanisms such as UUCP, provided they can
545 handle domain-style addresses. Batched SMTP input is also catered for.
546 .next
547 Exim is not designed for storing mail for dial-in hosts. When the volumes of
548 such mail are large, it is better to get the messages &"delivered"& into files
549 (that is, off Exim's queue) and subsequently passed on to the dial-in hosts by
550 other means.
551 .next
552 Although Exim does have basic facilities for scanning incoming messages, these
553 are not comprehensive enough to do full virus or spam scanning. Such operations
554 are best carried out using additional specialized software packages. If you
555 compile Exim with the content-scanning extension, straightforward interfaces to
556 a number of common scanners are provided.
557 .endlist
560 .section "Run time configuration"
561 Exim's run time configuration is held in a single text file that is divided
562 into a number of sections. The entries in this file consist of keywords and
563 values, in the style of Smail 3 configuration files. A default configuration
564 file which is suitable for simple online installations is provided in the
565 distribution, and is described in chapter &<<CHAPdefconfil>>& below.
568 .section "Calling interface"
569 .cindex "Sendmail compatibility" "command line interface"
570 Like many MTAs, Exim has adopted the Sendmail command line interface so that it
571 can be a straight replacement for &_/usr/lib/sendmail_& or
572 &_/usr/sbin/sendmail_& when sending mail, but you do not need to know anything
573 about Sendmail in order to run Exim. For actions other than sending messages,
574 Sendmail-compatible options also exist, but those that produce output (for
575 example, &%-bp%&, which lists the messages on the queue) do so in Exim's own
576 format. There are also some additional options that are compatible with Smail
577 3, and some further options that are new to Exim. Chapter &<<CHAPcommandline>>&
578 documents all Exim's command line options. This information is automatically
579 made into the man page that forms part of the Exim distribution.
581 Control of messages on the queue can be done via certain privileged command
582 line options. There is also an optional monitor program called &'eximon'&,
583 which displays current information in an X window, and which contains a menu
584 interface to Exim's command line administration options.
588 .section "Terminology"
589 .cindex "terminology definitions"
590 .cindex "body of message" "definition of"
591 The &'body'& of a message is the actual data that the sender wants to transmit.
592 It is the last part of a message, and is separated from the &'header'& (see
593 below) by a blank line.
595 .cindex "bounce message" "definition of"
596 When a message cannot be delivered, it is normally returned to the sender in a
597 delivery failure message or a &"non-delivery report"& (NDR). The term
598 &'bounce'& is commonly used for this action, and the error reports are often
599 called &'bounce messages'&. This is a convenient shorthand for &"delivery
600 failure error report"&. Such messages have an empty sender address in the
601 message's &'envelope'& (see below) to ensure that they cannot themselves give
602 rise to further bounce messages.
604 The term &'default'& appears frequently in this manual. It is used to qualify a
605 value which is used in the absence of any setting in the configuration. It may
606 also qualify an action which is taken unless a configuration setting specifies
607 otherwise.
609 The term &'defer'& is used when the delivery of a message to a specific
610 destination cannot immediately take place for some reason (a remote host may be
611 down, or a user's local mailbox may be full). Such deliveries are &'deferred'&
612 until a later time.
614 The word &'domain'& is sometimes used to mean all but the first component of a
615 host's name. It is &'not'& used in that sense here, where it normally refers to
616 the part of an email address following the @ sign.
618 .cindex "envelope" "definition of"
619 .cindex "sender" "definition of"
620 A message in transit has an associated &'envelope'&, as well as a header and a
621 body. The envelope contains a sender address (to which bounce messages should
622 be delivered), and any number of recipient addresses. References to the
623 sender or the recipients of a message usually mean the addresses in the
624 envelope. An MTA uses these addresses for delivery, and for returning bounce
625 messages, not the addresses that appear in the header lines.
627 .cindex "message header" "definition of"
628 .cindex "header section" "definition of"
629 The &'header'& of a message is the first part of a message's text, consisting
630 of a number of lines, each of which has a name such as &'From:'&, &'To:'&,
631 &'Subject:'&, etc. Long header lines can be split over several text lines by
632 indenting the continuations. The header is separated from the body by a blank
633 line.
635 .cindex "local part" "definition of"
636 .cindex "domain" "definition of"
637 The term &'local part'&, which is taken from RFC 2822, is used to refer to that
638 part of an email address that precedes the @ sign. The part that follows the
639 @ sign is called the &'domain'& or &'mail domain'&.
641 .cindex "local delivery" "definition of"
642 .cindex "remote delivery" "definition of"
643 The terms &'local delivery'& and &'remote delivery'& are used to distinguish
644 delivery to a file or a pipe on the local host from delivery by SMTP over
645 TCP/IP to another host. As far as Exim is concerned, all hosts other than the
646 host it is running on are &'remote'&.
648 .cindex "return path" "definition of"
649 &'Return path'& is another name that is used for the sender address in a
650 message's envelope.
652 .cindex "queue" "definition of"
653 The term &'queue'& is used to refer to the set of messages awaiting delivery,
654 because this term is in widespread use in the context of MTAs. However, in
655 Exim's case the reality is more like a pool than a queue, because there is
656 normally no ordering of waiting messages.
658 .cindex "queue runner" "definition of"
659 The term &'queue runner'& is used to describe a process that scans the queue
660 and attempts to deliver those messages whose retry times have come. This term
661 is used by other MTAs, and also relates to the command &%runq%&, but in Exim
662 the waiting messages are normally processed in an unpredictable order.
664 .cindex "spool directory" "definition of"
665 The term &'spool directory'& is used for a directory in which Exim keeps the
666 messages on its queue &-- that is, those that it is in the process of
667 delivering. This should not be confused with the directory in which local
668 mailboxes are stored, which is called a &"spool directory"& by some people. In
669 the Exim documentation, &"spool"& is always used in the first sense.
676 . ////////////////////////////////////////////////////////////////////////////
677 . ////////////////////////////////////////////////////////////////////////////
679 .chapter "Incorporated code"
680 .cindex "incorporated code"
681 .cindex "regular expressions" "library"
682 .cindex "PCRE"
683 A number of pieces of external code are included in the Exim distribution.
685 .ilist
686 Regular expressions are supported in the main Exim program and in the Exim
687 monitor using the freely-distributable PCRE library, copyright &copy;
688 University of Cambridge. The source is distributed in the directory
689 &_src/pcre_&. However, this is a cut-down version of PCRE. If you want to use
690 the PCRE library in other programs, you should obtain and install the full
691 version from &url(ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre).
692 .next
693 .cindex "cdb" "acknowledgement"
694 Support for the cdb (Constant DataBase) lookup method is provided by code
695 contributed by Nigel Metheringham of (at the time he contributed it) Planet
696 Online Ltd. The implementation is completely contained within the code of Exim.
697 It does not link against an external cdb library. The code contains the
698 following statements:
700 .blockquote
701 Copyright &copy; 1998 Nigel Metheringham, Planet Online Ltd
703 This program is free software; you can redistribute it and/or modify it under
704 the terms of the GNU General Public License as published by the Free Software
705 Foundation; either version 2 of the License, or (at your option) any later
706 version.
708 This code implements Dan Bernstein's Constant DataBase (cdb) spec. Information,
709 the spec and sample code for cdb can be obtained from
710 &url(http://www.pobox.com/~djb/cdb.html). This implementation borrows some
711 code from Dan Bernstein's implementation (which has no license restrictions
712 applied to it).
713 .endblockquote
714 .next
715 .cindex "SPA authentication"
716 .cindex "Samba project"
717 .cindex "Microsoft Secure Password Authentication"
718 Client support for Microsoft's &'Secure Password Authentication'& is provided
719 by code contributed by Marc Prud'hommeaux. Server support was contributed by
720 Tom Kistner. This includes code taken from the Samba project, which is released
721 under the Gnu GPL.
722 .next
723 .cindex "Cyrus"
724 .cindex "&'pwcheck'& daemon"
725 .cindex "&'pwauthd'& daemon"
726 Support for calling the Cyrus &'pwcheck'& and &'saslauthd'& daemons is provided
727 by code taken from the Cyrus-SASL library and adapted by Alexander S.
728 Sabourenkov. The permission notice appears below, in accordance with the
729 conditions expressed therein.
731 .blockquote
732 Copyright &copy; 2001 Carnegie Mellon University. All rights reserved.
734 Redistribution and use in source and binary forms, with or without
735 modification, are permitted provided that the following conditions
736 are met:
738 .olist
739 Redistributions of source code must retain the above copyright
740 notice, this list of conditions and the following disclaimer.
741 .next
742 Redistributions in binary form must reproduce the above copyright
743 notice, this list of conditions and the following disclaimer in
744 the documentation and/or other materials provided with the
745 distribution.
746 .next
747 The name &"Carnegie Mellon University"& must not be used to
748 endorse or promote products derived from this software without
749 prior written permission. For permission or any other legal
750 details, please contact
751 .display
752 Office of Technology Transfer
753 Carnegie Mellon University
754 5000 Forbes Avenue
755 Pittsburgh, PA 15213-3890
756 (412) 268-4387, fax: (412) 268-7395
757 tech-transfer@andrew.cmu.edu
758 .endd
759 .next
760 Redistributions of any form whatsoever must retain the following
761 acknowledgment:
763 &"This product includes software developed by Computing Services
764 at Carnegie Mellon University (&url(http://www.cmu.edu/computing/)."&
773 .endlist
774 .endblockquote
776 .next
777 .cindex "Exim monitor" "acknowledgement"
778 .cindex "X-windows"
779 .cindex "Athena"
780 The Exim Monitor program, which is an X-Window application, includes
781 modified versions of the Athena StripChart and TextPop widgets.
782 This code is copyright by DEC and MIT, and their permission notice appears
783 below, in accordance with the conditions expressed therein.
785 .blockquote
786 Copyright 1987, 1988 by Digital Equipment Corporation, Maynard, Massachusetts,
787 and the Massachusetts Institute of Technology, Cambridge, Massachusetts.
789 All Rights Reserved
791 Permission to use, copy, modify, and distribute this software and its
792 documentation for any purpose and without fee is hereby granted,
793 provided that the above copyright notice appear in all copies and that
794 both that copyright notice and this permission notice appear in
795 supporting documentation, and that the names of Digital or MIT not be
796 used in advertising or publicity pertaining to distribution of the
797 software without specific, written prior permission.
806 .endblockquote
808 .next
809 Many people have contributed code fragments, some large, some small, that were
810 not covered by any specific licence requirements. It is assumed that the
811 contributors are happy to see their code incoporated into Exim under the GPL.
812 .endlist
818 . ////////////////////////////////////////////////////////////////////////////
819 . ////////////////////////////////////////////////////////////////////////////
821 .chapter "How Exim receives and delivers mail" "" &&&
822 "Receiving and delivering mail"
825 .section "Overall philosophy"
826 .cindex "design philosophy"
827 Exim is designed to work efficiently on systems that are permanently connected
828 to the Internet and are handling a general mix of mail. In such circumstances,
829 most messages can be delivered immediately. Consequently, Exim does not
830 maintain independent queues of messages for specific domains or hosts, though
831 it does try to send several messages in a single SMTP connection after a host
832 has been down, and it also maintains per-host retry information.
835 .section "Policy control"
836 .cindex "policy control" "overview"
837 Policy controls are now an important feature of MTAs that are connected to the
838 Internet. Perhaps their most important job is to stop MTAs being abused as
839 &"open relays"& by misguided individuals who send out vast amounts of
840 unsolicited junk, and want to disguise its source. Exim provides flexible
841 facilities for specifying policy controls on incoming mail:
843 .ilist
844 .cindex "&ACL;" "introduction"
845 Exim 4 (unlike previous versions of Exim) implements policy controls on
846 incoming mail by means of &'Access Control Lists'& (ACLs). Each list is a
847 series of statements that may either grant or deny access. ACLs can be used at
848 several places in the SMTP dialogue while receiving a message from a remote
849 host. However, the most common places are after each RCPT command, and at the
850 very end of the message. The sysadmin can specify conditions for accepting or
851 rejecting individual recipients or the entire message, respectively, at these
852 two points (see chapter &<<CHAPACL>>&). Denial of access results in an SMTP
853 error code.
854 .next
855 An ACL is also available for locally generated, non-SMTP messages. In this
856 case, the only available actions are to accept or deny the entire message.
857 .next
858 When Exim is compiled with the content-scanning extension, facilities are
859 provided in the ACL mechanism for passing the message to external virus and/or
860 spam scanning software. The result of such a scan is passed back to the ACL,
861 which can then use it to decide what to do with the message.
862 .next
863 When a message has been received, either from a remote host or from the local
864 host, but before the final acknowledgement has been sent, a locally supplied C
865 function called &[local_scan()]& can be run to inspect the message and decide
866 whether to accept it or not (see chapter &<<CHAPlocalscan>>&). If the message
867 is accepted, the list of recipients can be modified by the function.
868 .next
869 Using the &[local_scan()]& mechanism is another way of calling external scanner
870 software. The &%SA-Exim%& add-on package works this way. It does not require
871 Exim to be compiled with the content-scanning extension.
872 .next
873 After a message has been accepted, a further checking mechanism is available in
874 the form of the &'system filter'& (see chapter &<<CHAPsystemfilter>>&). This
875 runs at the start of every delivery process.
876 .endlist
880 .section "User filters"
881 .cindex "filter" "introduction"
882 .cindex "Sieve filter"
883 In a conventional Exim configuration, users are able to run private filters by
884 setting up appropriate &_.forward_& files in their home directories. See
885 chapter &<<CHAPredirect>>& (about the &(redirect)& router) for the
886 configuration needed to support this, and the separate document entitled
887 &'Exim's interfaces to mail filtering'& for user details. Two different kinds
888 of filtering are available:
890 .ilist
891 Sieve filters are written in the standard filtering language that is defined
892 by RFC 3028.
893 .next
894 Exim filters are written in a syntax that is unique to Exim, but which is more
895 powerful than Sieve, which it pre-dates.
896 .endlist
898 User filters are run as part of the routing process, described below.
902 .section "Message identification" "SECTmessiden"
903 .cindex "message ids" "details of format"
904 .cindex "format" "of message id"
905 .cindex "id of message"
906 .cindex "base62"
907 .cindex "base36"
908 .cindex "Darwin"
909 .cindex "Cygwin"
910 Every message handled by Exim is given a &'message id'& which is sixteen
911 characters long. It is divided into three parts, separated by hyphens, for
912 example &`16VDhn-0001bo-D3`&. Each part is a sequence of letters and digits,
913 normally encoding numbers in base 62. However, in the Darwin operating
914 system (Mac OS X) and when Exim is compiled to run under Cygwin, base 36
915 (avoiding the use of lower case letters) is used instead, because the message
916 id is used to construct file names, and the names of files in those systems are
917 not always case-sensitive.
919 .cindex "pid (process id)" "re-use of"
920 The detail of the contents of the message id have changed as Exim has evolved.
921 Earlier versions relied on the operating system not re-using a process id (pid)
922 within one second. On modern operating systems, this assumption can no longer
923 be made, so the algorithm had to be changed. To retain backward compatibility,
924 the format of the message id was retained, which is why the following rules are
925 somewhat eccentric:
927 .ilist
928 The first six characters of the message id are the time at which the message
929 started to be received, to a granularity of one second. That is, this field
930 contains the number of seconds since the start of the epoch (the normal Unix
931 way of representing the date and time of day).
932 .next
933 After the first hyphen, the next six characters are the id of the process that
934 received the message.
935 .next
936 There are two different possibilities for the final two characters:
937 .olist
938 .cindex "&%localhost_number%&"
939 If &%localhost_number%& is not set, this value is the fractional part of the
940 time of reception, normally in units of 1/2000 of a second, but for systems
941 that must use base 36 instead of base 62 (because of case-insensitive file
942 systems), the units are 1/1000 of a second.
943 .next
944 If &%localhost_number%& is set, it is multiplied by 200 (100) and added to
945 the fractional part of the time, which in this case is in units of 1/200
946 (1/100) of a second.
947 .endlist
948 .endlist
950 After a message has been received, Exim waits for the clock to tick at the
951 appropriate resolution before proceeding, so that if another message is
952 received by the same process, or by another process with the same (re-used)
953 pid, it is guaranteed that the time will be different. In most cases, the clock
954 will already have ticked while the message was being received.
957 .section "Receiving mail"
958 .cindex "receiving mail"
959 .cindex "message" "reception"
960 The only way Exim can receive mail from another host is using SMTP over
961 TCP/IP, in which case the sender and recipient addresses are transferred using
962 SMTP commands. However, from a locally running process (such as a user's MUA),
963 there are several possibilities:
965 .ilist
966 If the process runs Exim with the &%-bm%& option, the message is read
967 non-interactively (usually via a pipe), with the recipients taken from the
968 command line, or from the body of the message if &%-t%& is also used.
969 .next
970 If the process runs Exim with the &%-bS%& option, the message is also read
971 non-interactively, but in this case the recipients are listed at the start of
972 the message in a series of SMTP RCPT commands, terminated by a DATA
973 command. This is so-called &"batch SMTP"& format,
974 but it isn't really SMTP. The SMTP commands are just another way of passing
975 envelope addresses in a non-interactive submission.
976 .next
977 If the process runs Exim with the &%-bs%& option, the message is read
978 interactively, using the SMTP protocol. A two-way pipe is normally used for
979 passing data between the local process and the Exim process.
980 This is &"real"& SMTP and is handled in the same way as SMTP over TCP/IP. For
981 example, the ACLs for SMTP commands are used for this form of submission.
982 .next
983 A local process may also make a TCP/IP call to the host's loopback address
984 ( or any other of its IP addresses. When receiving messages, Exim
985 does not treat the loopback address specially. It treats all such connections
986 in the same way as connections from other hosts.
987 .endlist
990 .cindex "message sender" "constructed by Exim"
991 .cindex "sender" "constructed by Exim"
992 In the three cases that do not involve TCP/IP, the sender address is
993 constructed from the login name of the user that called Exim and a default
994 qualification domain (which can be set by the &%qualify_domain%& configuration
995 option). For local or batch SMTP, a sender address that is passed using the
996 SMTP MAIL command is ignored. However, the system administrator may allow
997 certain users (&"trusted users"&) to specify a different sender address
998 unconditionally, or all users to specify certain forms of different sender
999 address. The &%-f%& option or the SMTP MAIL command is used to specify these
1000 different addresses. See section &<<SECTtrustedadmin>>& for details of trusted
1001 users, and the &%untrusted_set_sender%& option for a way of allowing untrusted
1002 users to change sender addresses.
1004 Messages received by either of the non-interactive mechanisms are subject to
1005 checking by the non-SMTP ACL, if one is defined. Messages received using SMTP
1006 (either over TCP/IP, or interacting with a local process) can be checked by a
1007 number of ACLs that operate at different times during the SMTP session. Either
1008 individual recipients, or the entire message, can be rejected if local policy
1009 requirements are not met. The &[local_scan()]& function (see chapter
1010 &<<CHAPlocalscan>>&) is run for all incoming messages.
1012 Exim can be configured not to start a delivery process when a message is
1013 received; this can be unconditional, or depend on the number of incoming SMTP
1014 connections or the system load. In these situations, new messages wait on the
1015 queue until a queue runner process picks them up. However, in standard
1016 configurations under normal conditions, delivery is started as soon as a
1017 message is received.
1023 .section "Handling an incoming message"
1024 .cindex "spool directory" "files that hold a message"
1025 .cindex "file" "how a message is held"
1026 When Exim accepts a message, it writes two files in its spool directory. The
1027 first contains the envelope information, the current status of the message, and
1028 the header lines, and the second contains the body of the message. The names of
1029 the two spool files consist of the message id, followed by &`-H`& for the
1030 file containing the envelope and header, and &`-D`& for the data file.
1032 .cindex "spool directory" "&_input_& sub-directory"
1033 By default all these message files are held in a single directory called
1034 &_input_& inside the general Exim spool directory. Some operating systems do
1035 not perform very well if the number of files in a directory gets very large; to
1036 improve performance in such cases, the &%split_spool_directory%& option can be
1037 used. This causes Exim to split up the input files into 62 sub-directories
1038 whose names are single letters or digits.
1040 The envelope information consists of the address of the message's sender and
1041 the addresses of the recipients. This information is entirely separate from
1042 any addresses contained in the header lines. The status of the message includes
1043 a list of recipients who have already received the message. The format of the
1044 first spool file is described in chapter &<<CHAPspool>>&.
1046 .cindex "rewriting" "addresses"
1047 Address rewriting that is specified in the rewrite section of the configuration
1048 (see chapter &<<CHAPrewrite>>&) is done once and for all on incoming addresses,
1049 both in the header lines and the envelope, at the time the message is accepted.
1050 If during the course of delivery additional addresses are generated (for
1051 example, via aliasing), these new addresses are rewritten as soon as they are
1052 generated. At the time a message is actually delivered (transported) further
1053 rewriting can take place; because this is a transport option, it can be
1054 different for different forms of delivery. It is also possible to specify the
1055 addition or removal of certain header lines at the time the message is
1056 delivered (see chapters &<<CHAProutergeneric>>& and
1057 &<<CHAPtransportgeneric>>&).
1061 .section "Life of a message"
1062 .cindex "message" "life of"
1063 .cindex "message" "frozen"
1064 A message remains in the spool directory until it is completely delivered to
1065 its recipients or to an error address, or until it is deleted by an
1066 administrator or by the user who originally created it. In cases when delivery
1067 cannot proceed &-- for example, when a message can neither be delivered to its
1068 recipients nor returned to its sender, the message is marked &"frozen"& on the
1069 spool, and no more deliveries are attempted.
1071 .cindex "frozen messages" "thawing"
1072 .cindex "message" "thawing frozen"
1073 An administrator can &"thaw"& such messages when the problem has been
1074 corrected, and can also freeze individual messages by hand if necessary. In
1075 addition, an administrator can force a delivery error, causing a bounce message
1076 to be sent.
1078 .cindex "&%timeout_frozen_after%&"
1079 .cindex "&%ignore_bounce_errors_after%&"
1080 There are options called &%ignore_bounce_errors_after%& and
1081 &%timeout_frozen_after%&, which discard frozen messages after a certain time.
1082 The first applies only to frozen bounces, the second to any frozen messages.
1084 .cindex "message" "log file for"
1085 .cindex "log" "file for each message"
1086 While Exim is working on a message, it writes information about each delivery
1087 attempt to its main log file. This includes successful, unsuccessful, and
1088 delayed deliveries for each recipient (see chapter &<<CHAPlog>>&). The log
1089 lines are also written to a separate &'message log'& file for each message.
1090 These logs are solely for the benefit of the administrator, and are normally
1091 deleted along with the spool files when processing of a message is complete.
1092 The use of individual message logs can be disabled by setting
1093 &%no_message_logs%&; this might give an improvement in performance on very busy
1094 systems.
1096 .cindex "journal file"
1097 .cindex "file" "journal"
1098 All the information Exim itself needs to set up a delivery is kept in the first
1099 spool file, along with the header lines. When a successful delivery occurs, the
1100 address is immediately written at the end of a journal file, whose name is the
1101 message id followed by &`-J`&. At the end of a delivery run, if there are some
1102 addresses left to be tried again later, the first spool file (the &`-H`& file)
1103 is updated to indicate which these are, and the journal file is then deleted.
1104 Updating the spool file is done by writing a new file and renaming it, to
1105 minimize the possibility of data loss.
1107 Should the system or the program crash after a successful delivery but before
1108 the spool file has been updated, the journal is left lying around. The next
1109 time Exim attempts to deliver the message, it reads the journal file and
1110 updates the spool file before proceeding. This minimizes the chances of double
1111 deliveries caused by crashes.
1115 .section "Processing an address for delivery" "SECTprocaddress"
1116 .cindex "drivers" "definition of"
1117 .cindex "router" "definition of"
1118 .cindex "transport" "definition of"
1119 The main delivery processing elements of Exim are called &'routers'& and
1120 &'transports'&, and collectively these are known as &'drivers'&. Code for a
1121 number of them is provided in the source distribution, and compile-time options
1122 specify which ones are included in the binary. Run time options specify which
1123 ones are actually used for delivering messages.
1125 .cindex "drivers" "instance definition"
1126 Each driver that is specified in the run time configuration is an &'instance'&
1127 of that particular driver type. Multiple instances are allowed; for example,
1128 you can set up several different &(smtp)& transports, each with different
1129 option values that might specify different ports or different timeouts. Each
1130 instance has its own identifying name. In what follows we will normally use the
1131 instance name when discussing one particular instance (that is, one specific
1132 configuration of the driver), and the generic driver name when discussing
1133 the driver's features in general.
1135 A &'router'& is a driver that operates on an address, either determining how
1136 its delivery should happen, by assigning it to a specific transport, or
1137 converting the address into one or more new addresses (for example, via an
1138 alias file). A router may also explicitly choose to fail an address, causing it
1139 to be bounced.
1141 A &'transport'& is a driver that transmits a copy of the message from Exim's
1142 spool to some destination. There are two kinds of transport: for a &'local'&
1143 transport, the destination is a file or a pipe on the local host, whereas for a
1144 &'remote'& transport the destination is some other host. A message is passed
1145 to a specific transport as a result of successful routing. If a message has
1146 several recipients, it may be passed to a number of different transports.
1148 .cindex "preconditions" "definition of"
1149 An address is processed by passing it to each configured router instance in
1150 turn, subject to certain preconditions, until a router accepts the address or
1151 specifies that it should be bounced. We will describe this process in more
1152 detail shortly. First, as a simple example, we consider how each recipient
1153 address in a message is processed in a small configuration of three routers.
1155 To make this a more concrete example, it is described in terms of some actual
1156 routers, but remember, this is only an example. You can configure Exim's
1157 routers in many different ways, and there may be any number of routers in a
1158 configuration.
1160 The first router that is specified in a configuration is often one that handles
1161 addresses in domains that are not recognized specially by the local host. These
1162 are typically addresses for arbitrary domains on the Internet. A precondition
1163 is set up which looks for the special domains known to the host (for example,
1164 its own domain name), and the router is run for addresses that do &'not'&
1165 match. Typically, this is a router that looks up domains in the DNS in order to
1166 find the hosts to which this address routes. If it succeeds, the address is
1167 assigned to a suitable SMTP transport; if it does not succeed, the router is
1168 configured to fail the address.
1170 The second router is reached only when the domain is recognized as one that
1171 &"belongs"& to the local host. This router does redirection &-- also known as
1172 aliasing and forwarding. When it generates one or more new addresses from the
1173 original, each of them is routed independently from the start. Otherwise, the
1174 router may cause an address to fail, or it may simply decline to handle the
1175 address, in which case the address is passed to the next router.
1177 The final router in many configurations is one that checks to see if the
1178 address belongs to a local mailbox. The precondition may involve a check to
1179 see if the local part is the name of a login account, or it may look up the
1180 local part in a file or a database. If its preconditions are not met, or if
1181 the router declines, we have reached the end of the routers. When this happens,
1182 the address is bounced.
1186 .section "Processing an address for verification"
1187 .cindex "router" "for verification"
1188 .cindex "verifying address" "overview"
1189 As well as being used to decide how to deliver to an address, Exim's routers
1190 are also used for &'address verification'&. Verification can be requested as
1191 one of the checks to be performed in an ACL for incoming messages, on both
1192 sender and recipient addresses, and it can be tested using the &%-bv%& and
1193 &%-bvs%& command line options.
1195 When an address is being verified, the routers are run in &"verify mode"&. This
1196 does not affect the way the routers work, but it is a state that can be
1197 detected. By this means, a router can be skipped or made to behave differently
1198 when verifying. A common example is a configuration in which the first router
1199 sends all messages to a message-scanning program, unless they have been
1200 previously scanned. Thus, the first router accepts all addresses without any
1201 checking, making it useless for verifying. Normally, the &%no_verify%& option
1202 would be set for such a router, causing it to be skipped in verify mode.
1207 .section "Running an individual router" "SECTrunindrou"
1208 .cindex "router" "running details"
1209 .cindex "preconditions" "checking"
1210 .cindex "router" "result of running"
1211 As explained in the example above, a number of preconditions are checked before
1212 running a router. If any are not met, the router is skipped, and the address is
1213 passed to the next router. When all the preconditions on a router &'are'& met,
1214 the router is run. What happens next depends on the outcome, which is one of
1215 the following:
1217 .ilist
1218 &'accept'&: The router accepts the address, and either assigns it to a
1219 transport, or generates one or more &"child"& addresses. Processing the
1220 original address ceases,
1221 .cindex "&%unseen%& option"
1222 unless the &%unseen%& option is set on the router. This option
1223 can be used to set up multiple deliveries with different routing (for example,
1224 for keeping archive copies of messages). When &%unseen%& is set, the address is
1225 passed to the next router. Normally, however, an &'accept'& return marks the
1226 end of routing.
1228 Any child addresses generated by the router are processed independently,
1229 starting with the first router by default. It is possible to change this by
1230 setting the &%redirect_router%& option to specify which router to start at for
1231 child addresses. Unlike &%pass_router%& (see below) the router specified by
1232 &%redirect_router%& may be anywhere in the router configuration.
1233 .next
1234 &'pass'&: The router recognizes the address, but cannot handle it itself. It
1235 requests that the address be passed to another router. By default the address
1236 is passed to the next router, but this can be changed by setting the
1237 &%pass_router%& option. However, (unlike &%redirect_router%&) the named router
1238 must be below the current router (to avoid loops).
1239 .next
1240 &'decline'&: The router declines to accept the address because it does not
1241 recognize it at all. By default, the address is passed to the next router, but
1242 this can be prevented by setting the &%no_more%& option. When &%no_more%& is
1243 set, all the remaining routers are skipped. In effect, &%no_more%& converts
1244 &'decline'& into &'fail'&.
1245 .next
1246 &'fail'&: The router determines that the address should fail, and queues it for
1247 the generation of a bounce message. There is no further processing of the
1248 original address unless &%unseen%& is set on the router.
1249 .next
1250 &'defer'&: The router cannot handle the address at the present time. (A
1251 database may be offline, or a DNS lookup may have timed out.) No further
1252 processing of the address happens in this delivery attempt. It is tried again
1253 next time the message is considered for delivery.
1254 .next
1255 &'error'&: There is some error in the router (for example, a syntax error in
1256 its configuration). The action is as for defer.
1257 .endlist
1259 If an address reaches the end of the routers without having been accepted by
1260 any of them, it is bounced as unrouteable. The default error message in this
1261 situation is &"unrouteable address"&, but you can set your own message by
1262 making use of the &%cannot_route_message%& option. This can be set for any
1263 router; the value from the last router that &"saw"& the address is used.
1265 Sometimes while routing you want to fail a delivery when some conditions are
1266 met but others are not, instead of passing the address on for further routing.
1267 You can do this by having a second router that explicitly fails the delivery
1268 when the relevant conditions are met. The &(redirect)& router has a &"fail"&
1269 facility for this purpose.
1272 .section "Duplicate addresses"
1273 .cindex "case of local parts"
1274 .cindex "address duplicate" "discarding"
1275 Once routing is complete, Exim scans the addresses that are assigned to local
1276 and remote transports, and discards any duplicates that it finds. During this
1277 check, local parts are treated as case-sensitive.
1280 .section "Router preconditions" "SECTrouprecon"
1281 .cindex "router preconditions" "order of processing"
1282 .cindex "preconditions" "order of processing"
1283 The preconditions that are tested for each router are listed below, in the
1284 order in which they are tested. The individual configuration options are
1285 described in more detail in chapter &<<CHAProutergeneric>>&.
1287 .ilist
1288 The &%local_part_prefix%& and &%local_part_suffix%& options can specify that
1289 the local parts handled by the router may or must have certain prefixes and/or
1290 suffixes. If a mandatory affix (prefix or suffix) is not present, the router is
1291 skipped. These conditions are tested first. When an affix is present, it is
1292 removed from the local part before further processing, including the evaluation
1293 of any other conditions.
1294 .next
1295 Routers can be designated for use only when not verifying an address, that is,
1296 only when routing it for delivery (or testing its delivery routing). If the
1297 &%verify%& option is set false, the router is skipped when Exim is verifying an
1298 address.
1299 Setting the &%verify%& option actually sets two options, &%verify_sender%& and
1300 &%verify_recipient%&, which independently control the use of the router for
1301 sender and recipient verification. You can set these options directly if
1302 you want a router to be used for only one type of verification.
1303 .next
1304 If the &%address_test%& option is set false, the router is skipped when Exim is
1305 run with the &%-bt%& option to test an address routing. This can be helpful
1306 when the first router sends all new messages to a scanner of some sort; it
1307 makes it possible to use &%-bt%& to test subsequent delivery routing without
1308 having to simulate the effect of the scanner.
1309 .next
1310 Routers can be designated for use only when verifying an address, as
1311 opposed to routing it for delivery. The &%verify_only%& option controls this.
1312 .next
1313 Individual routers can be explicitly skipped when running the routers to
1314 check an address given in the SMTP EXPN command (see the &%expn%& option).
1315 .next
1316 If the &%domains%& option is set, the domain of the address must be in the set
1317 of domains that it defines.
1318 .next
1319 .cindex "&$local_part_prefix$&"
1320 .cindex "&$local_part$&"
1321 .cindex "&$local_part_suffix$&"
1322 If the &%local_parts%& option is set, the local part of the address must be in
1323 the set of local parts that it defines. If &%local_part_prefix%& or
1324 &%local_part_suffix%& is in use, the prefix or suffix is removed from the local
1325 part before this check. If you want to do precondition tests on local parts
1326 that include affixes, you can do so by using a &%condition%& option (see below)
1327 that uses the variables &$local_part$&, &$local_part_prefix$&, and
1328 &$local_part_suffix$& as necessary.
1329 .next
1330 .cindex "&$local_user_uid$&"
1331 .cindex "&$local_user_gid$&"
1332 .cindex "&$home$&"
1333 If the &%check_local_user%& option is set, the local part must be the name of
1334 an account on the local host. If this check succeeds, the uid and gid of the
1335 local user are placed in &$local_user_uid$& and &$local_user_gid$& and the
1336 user's home directory is placed in &$home$&; these values can be used in the
1337 remaining preconditions.
1338 .next
1339 If the &%router_home_directory%& option is set, it is expanded at this point,
1340 because it overrides the value of &$home$&. If this expansion were left till
1341 later, the value of &$home$& as set by &%check_local_user%& would be used in
1342 subsequent tests. Having two different values of &$home$& in the same router
1343 could lead to confusion.
1344 .next
1345 If the &%senders%& option is set, the envelope sender address must be in the
1346 set of addresses that it defines.
1347 .next
1348 If the &%require_files%& option is set, the existence or non-existence of
1349 specified files is tested.
1350 .next
1351 .cindex "customizing" "precondition"
1352 If the &%condition%& option is set, it is evaluated and tested. This option
1353 uses an expanded string to allow you to set up your own custom preconditions.
1354 Expanded strings are described in chapter &<<CHAPexpand>>&.
1355 .endlist
1358 Note that &%require_files%& comes near the end of the list, so you cannot use
1359 it to check for the existence of a file in which to lookup up a domain, local
1360 part, or sender. However, as these options are all expanded, you can use the
1361 &%exists%& expansion condition to make such tests within each condition. The
1362 &%require_files%& option is intended for checking files that the router may be
1363 going to use internally, or which are needed by a specific transport (for
1364 example, &_.procmailrc_&).
1368 .section "Delivery in detail"
1369 .cindex "delivery" "in detail"
1370 When a message is to be delivered, the sequence of events is as follows:
1372 .ilist
1373 If a system-wide filter file is specified, the message is passed to it. The
1374 filter may add recipients to the message, replace the recipients, discard the
1375 message, cause a new message to be generated, or cause the message delivery to
1376 fail. The format of the system filter file is the same as for Exim user filter
1377 files, described in the separate document entitled &'Exim's interfaces to mail
1378 filtering'&.
1379 .cindex "Sieve filter" "not available for system filter"
1380 (&*Note*&: Sieve cannot be used for system filter files.)
1382 Some additional features are available in system filters &-- see chapter
1383 &<<CHAPsystemfilter>>& for details. Note that a message is passed to the system
1384 filter only once per delivery attempt, however many recipients it has. However,
1385 if there are several delivery attempts because one or more addresses could not
1386 be immediately delivered, the system filter is run each time. The filter
1387 condition &%first_delivery%& can be used to detect the first run of the system
1388 filter.
1389 .next
1390 Each recipient address is offered to each configured router in turn, subject to
1391 its preconditions, until one is able to handle it. If no router can handle the
1392 address, that is, if they all decline, the address is failed. Because routers
1393 can be targeted at particular domains, several locally handled domains can be
1394 processed entirely independently of each other.
1395 .next
1396 .cindex "routing" "loops in"
1397 .cindex "loop" "while routing"
1398 A router that accepts an address may assign it to a local or a remote
1399 transport. However, the transport is not run at this time. Instead, the address
1400 is placed on a list for the particular transport, which will be run later.
1401 Alternatively, the router may generate one or more new addresses (typically
1402 from alias, forward, or filter files). New addresses are fed back into this
1403 process from the top, but in order to avoid loops, a router ignores any address
1404 which has an identically-named ancestor that was processed by itself.
1405 .next
1406 When all the routing has been done, addresses that have been successfully
1407 handled are passed to their assigned transports. When local transports are
1408 doing real local deliveries, they handle only one address at a time, but if a
1409 local transport is being used as a pseudo-remote transport (for example, to
1410 collect batched SMTP messages for transmission by some other means) multiple
1411 addresses can be handled. Remote transports can always handle more than one
1412 address at a time, but can be configured not to do so, or to restrict multiple
1413 addresses to the same domain.
1414 .next
1415 Each local delivery to a file or a pipe runs in a separate process under a
1416 non-privileged uid, and these deliveries are run one at a time. Remote
1417 deliveries also run in separate processes, normally under a uid that is private
1418 to Exim (&"the Exim user"&), but in this case, several remote deliveries can be
1419 run in parallel. The maximum number of simultaneous remote deliveries for any
1420 one message is set by the &%remote_max_parallel%& option.
1421 The order in which deliveries are done is not defined, except that all local
1422 deliveries happen before any remote deliveries.
1423 .next
1424 .cindex "queue runner"
1425 When it encounters a local delivery during a queue run, Exim checks its retry
1426 database to see if there has been a previous temporary delivery failure for the
1427 address before running the local transport. If there was a previous failure,
1428 Exim does not attempt a new delivery until the retry time for the address is
1429 reached. However, this happens only for delivery attempts that are part of a
1430 queue run. Local deliveries are always attempted when delivery immediately
1431 follows message reception, even if retry times are set for them. This makes for
1432 better behaviour if one particular message is causing problems (for example,
1433 causing quota overflow, or provoking an error in a filter file).
1434 .next
1435 .cindex "delivery" "retry in remote transports"
1436 Remote transports do their own retry handling, since an address may be
1437 deliverable to one of a number of hosts, each of which may have a different
1438 retry time. If there have been previous temporary failures and no host has
1439 reached its retry time, no delivery is attempted, whether in a queue run or
1440 not. See chapter &<<CHAPretry>>& for details of retry strategies.
1441 .next
1442 If there were any permanent errors, a bounce message is returned to an
1443 appropriate address (the sender in the common case), with details of the error
1444 for each failing address. Exim can be configured to send copies of bounce
1445 messages to other addresses.
1446 .next
1447 .cindex "delivery" "deferral"
1448 If one or more addresses suffered a temporary failure, the message is left on
1449 the queue, to be tried again later. Delivery of these addresses is said to be
1450 &'deferred'&.
1451 .next
1452 When all the recipient addresses have either been delivered or bounced,
1453 handling of the message is complete. The spool files and message log are
1454 deleted, though the message log can optionally be preserved if required.
1455 .endlist
1460 .section "Retry mechanism"
1461 .cindex "delivery" "retry mechanism"
1462 .cindex "retry" "description of mechanism"
1463 .cindex "queue runner"
1464 Exim's mechanism for retrying messages that fail to get delivered at the first
1465 attempt is the queue runner process. You must either run an Exim daemon that
1466 uses the &%-q%& option with a time interval to start queue runners at regular
1467 intervals, or use some other means (such as &'cron'&) to start them. If you do
1468 not arrange for queue runners to be run, messages that fail temporarily at the
1469 first attempt will remain on your queue for ever. A queue runner process works
1470 its way through the queue, one message at a time, trying each delivery that has
1471 passed its retry time.
1472 You can run several queue runners at once.
1474 Exim uses a set of configured rules to determine when next to retry the failing
1475 address (see chapter &<<CHAPretry>>&). These rules also specify when Exim
1476 should give up trying to deliver to the address, at which point it generates a
1477 bounce message. If no retry rules are set for a particular host, address, and
1478 error combination, no retries are attempted, and temporary errors are treated
1479 as permanent.
1483 .section "Temporary delivery failure"
1484 .cindex "delivery" "temporary failure"
1485 There are many reasons why a message may not be immediately deliverable to a
1486 particular address. Failure to connect to a remote machine (because it, or the
1487 connection to it, is down) is one of the most common. Temporary failures may be
1488 detected during routing as well as during the transport stage of delivery.
1489 Local deliveries may be delayed if NFS files are unavailable, or if a mailbox
1490 is on a file system where the user is over quota. Exim can be configured to
1491 impose its own quotas on local mailboxes; where system quotas are set they will
1492 also apply.
1494 If a host is unreachable for a period of time, a number of messages may be
1495 waiting for it by the time it recovers, and sending them in a single SMTP
1496 connection is clearly beneficial. Whenever a delivery to a remote host is
1497 deferred,
1499 .cindex "hints database"
1500 Exim makes a note in its hints database, and whenever a successful
1501 SMTP delivery has happened, it looks to see if any other messages are waiting
1502 for the same host. If any are found, they are sent over the same SMTP
1503 connection, subject to a configuration limit as to the maximum number in any
1504 one connection.
1509 .section "Permanent delivery failure"
1510 .cindex "delivery" "permanent failure"
1511 .cindex "bounce message" "when generated"
1512 When a message cannot be delivered to some or all of its intended recipients, a
1513 bounce message is generated. Temporary delivery failures turn into permanent
1514 errors when their timeout expires. All the addresses that fail in a given
1515 delivery attempt are listed in a single message. If the original message has
1516 many recipients, it is possible for some addresses to fail in one delivery
1517 attempt and others to fail subsequently, giving rise to more than one bounce
1518 message. The wording of bounce messages can be customized by the administrator.
1519 See chapter &<<CHAPemsgcust>>& for details.
1521 .cindex "&'X-Failed-Recipients:'& header line"
1522 Bounce messages contain an &'X-Failed-Recipients:'& header line that lists the
1523 failed addresses, for the benefit of programs that try to analyse such messages
1524 automatically.
1526 .cindex "bounce message" "recipient of"
1527 A bounce message is normally sent to the sender of the original message, as
1528 obtained from the message's envelope. For incoming SMTP messages, this is the
1529 address given in the MAIL command. However, when an address is expanded via a
1530 forward or alias file, an alternative address can be specified for delivery
1531 failures of the generated addresses. For a mailing list expansion (see section
1532 &<<SECTmailinglists>>&) it is common to direct bounce messages to the manager
1533 of the list.
1537 .section "Failures to deliver bounce messages"
1538 .cindex "bounce message" "failure to deliver"
1539 If a bounce message (either locally generated or received from a remote host)
1540 itself suffers a permanent delivery failure, the message is left on the queue,
1541 but it is frozen, awaiting the attention of an administrator. There are options
1542 that can be used to make Exim discard such failed messages, or to keep them
1543 for only a short time (see &%timeout_frozen_after%& and
1544 &%ignore_bounce_errors_after%&).
1550 . ////////////////////////////////////////////////////////////////////////////
1551 . ////////////////////////////////////////////////////////////////////////////
1553 .chapter "Building and installing Exim"
1554 .scindex IIDbuex "building Exim"
1556 .section "Unpacking"
1557 Exim is distributed as a gzipped or bzipped tar file which, when upacked,
1558 creates a directory with the name of the current release (for example,
1559 &_exim-&version;_&) into which the following files are placed:
1561 .table2 140pt
1562 .row &_ACKNOWLEDGMENTS_& "contains some acknowledgments"
1563 .row &_CHANGES_& "contains a reference to where changes are documented"
1564 .row &_LICENCE_& "the GNU General Public Licence"
1565 .row &_Makefile_& "top-level make file"
1566 .row &_NOTICE_& "conditions for the use of Exim"
1567 .row &_README_& "list of files, directories and simple build &&&
1568 instructions"
1569 .endtable
1571 Other files whose names begin with &_README_& may also be present. The
1572 following subdirectories are created:
1574 .table2 140pt
1575 .row &_Local_& "an empty directory for local configuration files"
1576 .row &_OS_& "OS-specific files"
1577 .row &_doc_& "documentation files"
1578 .row &_exim_monitor_& "source files for the Exim monitor"
1579 .row &_scripts_& "scripts used in the build process"
1580 .row &_src_& "remaining source files"
1581 .row &_util_& "independent utilities"
1582 .endtable
1584 The main utility programs are contained in the &_src_& directory, and are built
1585 with the Exim binary. The &_util_& directory contains a few optional scripts
1586 that may be useful to some sites.
1589 .section "Multiple machine architectures and operating systems"
1590 .cindex "building Exim" "multiple OS/architectures"
1591 The building process for Exim is arranged to make it easy to build binaries for
1592 a number of different architectures and operating systems from the same set of
1593 source files. Compilation does not take place in the &_src_& directory.
1594 Instead, a &'build directory'& is created for each architecture and operating
1595 system.
1596 .cindex "symbolic link" "to build directory"
1597 Symbolic links to the sources are installed in this directory, which is where
1598 the actual building takes place. In most cases, Exim can discover the machine
1599 architecture and operating system for itself, but the defaults can be
1600 overridden if necessary.
1603 .section "DBM libraries" "SECTdb"
1604 .cindex "DBM libraries" "discussion of"
1605 .cindex "hints database" "DBM files used for"
1606 Even if you do not use any DBM files in your configuration, Exim still needs a
1607 DBM library in order to operate, because it uses indexed files for its hints
1608 databases. Unfortunately, there are a number of DBM libraries in existence, and
1609 different operating systems often have different ones installed.
1611 .cindex "Solaris" "DBM library for"
1612 .cindex "IRIX" "DBM library for"
1613 .cindex "BSD" "DBM library for"
1614 .cindex "Linux" "DBM library for"
1615 If you are using Solaris, IRIX, one of the modern BSD systems, or a modern
1616 Linux distribution, the DBM configuration should happen automatically, and you
1617 may be able to ignore this section. Otherwise, you may have to learn more than
1618 you would like about DBM libraries from what follows.
1620 .cindex "&'ndbm'& DBM library"
1621 Licensed versions of Unix normally contain a library of DBM functions operating
1622 via the &'ndbm'& interface, and this is what Exim expects by default. Free
1623 versions of Unix seem to vary in what they contain as standard. In particular,
1624 some early versions of Linux have no default DBM library, and different
1625 distributors have chosen to bundle different libraries with their packaged
1626 versions. However, the more recent releases seem to have standardised on the
1627 Berkeley DB library.
1629 Different DBM libraries have different conventions for naming the files they
1630 use. When a program opens a file called &_dbmfile_&, there are several
1631 possibilities:
1633 .olist
1634 A traditional &'ndbm'& implementation, such as that supplied as part of
1635 Solaris, operates on two files called &_dbmfile.dir_& and &_dbmfile.pag_&.
1636 .next
1637 .cindex "&'gdbm'& DBM library"
1638 The GNU library, &'gdbm'&, operates on a single file. If used via its &'ndbm'&
1639 compatibility interface it makes two different hard links to it with names
1640 &_dbmfile.dir_& and &_dbmfile.pag_&, but if used via its native interface, the
1641 file name is used unmodified.
1642 .next
1643 .cindex "Berkeley DB library"
1644 The Berkeley DB package, if called via its &'ndbm'& compatibility interface,
1645 operates on a single file called &_dbmfile.db_&, but otherwise looks to the
1646 programmer exactly the same as the traditional &'ndbm'& implementation.
1647 .next
1648 If the Berkeley package is used in its native mode, it operates on a single
1649 file called &_dbmfile_&; the programmer's interface is somewhat different to
1650 the traditional &'ndbm'& interface.
1651 .next
1652 To complicate things further, there are several very different versions of the
1653 Berkeley DB package. Version 1.85 was stable for a very long time, releases
1654 2.&'x'& and 3.&'x'& were current for a while, but the latest versions are now
1655 numbered 4.&'x'&. Maintenance of some of the earlier releases has ceased. All
1656 versions of Berkeley DB can be obtained from
1657 &url(http://www.sleepycat.com/).
1658 .next
1659 .cindex "&'tdb'& DBM library"
1660 Yet another DBM library, called &'tdb'&, is available from
1661 &url(http://download.sourceforge.net/tdb). It has its own interface, and also
1662 operates on a single file.
1663 .endlist
1665 .cindex "USE_DB"
1666 .cindex "DBM libraries" "configuration for building"
1667 Exim and its utilities can be compiled to use any of these interfaces. In order
1668 to use any version of the Berkeley DB package in native mode, you must set
1669 USE_DB in an appropriate configuration file (typically
1670 &_Local/Makefile_&). For example:
1671 .code
1672 USE_DB=yes
1673 .endd
1674 Similarly, for gdbm you set USE_GDBM, and for tdb you set USE_TDB. An
1675 error is diagnosed if you set more than one of these.
1677 At the lowest level, the build-time configuration sets none of these options,
1678 thereby assuming an interface of type (1). However, some operating system
1679 configuration files (for example, those for the BSD operating systems and
1680 Linux) assume type (4) by setting USE_DB as their default, and the
1681 configuration files for Cygwin set USE_GDBM. Anything you set in
1682 &_Local/Makefile_&, however, overrides these system defaults.
1684 As well as setting USE_DB, USE_GDBM, or USE_TDB, it may also be
1685 necessary to set DBMLIB, to cause inclusion of the appropriate library, as
1686 in one of these lines:
1687 .code
1688 DBMLIB = -ldb
1689 DBMLIB = -ltdb
1690 .endd
1691 Settings like that will work if the DBM library is installed in the standard
1692 place. Sometimes it is not, and the library's header file may also not be in
1693 the default path. You may need to set INCLUDE to specify where the header
1694 file is, and to specify the path to the library more fully in DBMLIB, as in
1695 this example:
1696 .code
1697 INCLUDE=-I/usr/local/include/db-4.1
1698 DBMLIB=/usr/local/lib/db-4.1/libdb.a
1699 .endd
1700 There is further detailed discussion about the various DBM libraries in the
1701 file &_doc/dbm.discuss.txt_& in the Exim distribution.
1705 .section "Pre-building configuration"
1706 .cindex "building Exim" "pre-building configuration"
1707 .cindex "configuration for building Exim"
1708 .cindex "&_Local/Makefile_&"
1709 .cindex "&_src/EDITME_&"
1710 Before building Exim, a local configuration file that specifies options
1711 independent of any operating system has to be created with the name
1712 &_Local/Makefile_&. A template for this file is supplied as the file
1713 &_src/EDITME_&, and it contains full descriptions of all the option settings
1714 therein. These descriptions are therefore not repeated here. If you are
1715 building Exim for the first time, the simplest thing to do is to copy
1716 &_src/EDITME_& to &_Local/Makefile_&, then read it and edit it appropriately.
1718 There are three settings that you must supply, because Exim will not build
1719 without them. They are the location of the run time configuration file
1720 (CONFIGURE_FILE), the directory in which Exim binaries will be installed
1721 (BIN_DIRECTORY), and the identity of the Exim user (EXIM_USER and
1722 maybe EXIM_GROUP as well). The value of CONFIGURE_FILE can in fact be
1723 a colon-separated list of file names; Exim uses the first of them that exists.
1725 There are a few other parameters that can be specified either at build time or
1726 at run time, to enable the same binary to be used on a number of different
1727 machines. However, if the locations of Exim's spool directory and log file
1728 directory (if not within the spool directory) are fixed, it is recommended that
1729 you specify them in &_Local/Makefile_& instead of at run time, so that errors
1730 detected early in Exim's execution (such as a malformed configuration file) can
1731 be logged.
1733 .cindex "content scanning" "specifying at build time"
1734 Exim's interfaces for calling virus and spam scanning software directly from
1735 access control lists are not compiled by default. If you want to include these
1736 facilities, you need to set
1737 .code
1739 .endd
1740 in your &_Local/Makefile_&. For details of the facilities themselves, see
1741 chapter &<<CHAPexiscan>>&.
1744 .cindex "&_Local/eximon.conf_&"
1745 .cindex "_exim_monitor/EDITME_"
1746 If you are going to build the Exim monitor, a similar configuration process is
1747 required. The file &_exim_monitor/EDITME_& must be edited appropriately for
1748 your installation and saved under the name &_Local/eximon.conf_&. If you are
1749 happy with the default settings described in &_exim_monitor/EDITME_&,
1750 &_Local/eximon.conf_& can be empty, but it must exist.
1752 This is all the configuration that is needed in straightforward cases for known
1753 operating systems. However, the building process is set up so that it is easy
1754 to override options that are set by default or by operating-system-specific
1755 configuration files, for example to change the name of the C compiler, which
1756 defaults to &%gcc%&. See section &<<SECToverride>>& below for details of how to
1757 do this.
1761 .section "Support for iconv()"
1762 .cindex "&[iconv()]& support"
1763 .cindex "RFC 2047"
1764 The contents of header lines in messages may be encoded according to the rules
1765 described RFC 2047. This makes it possible to transmit characters that are not
1766 in the ASCII character set, and to label them as being in a particular
1767 character set. When Exim is inspecting header lines by means of the &%$h_%&
1768 mechanism, it decodes them, and translates them into a specified character set
1769 (default ISO-8859-1). The translation is possible only if the operating system
1770 supports the &[iconv()]& function.
1772 However, some of the operating systems that supply &[iconv()]& do not support
1773 very many conversions. The GNU &%libiconv%& library (available from
1774 &url(http://www.gnu.org/software/libiconv/)) can be installed on such
1775 systems to remedy this deficiency, as well as on systems that do not supply
1776 &[iconv()]& at all. After installing &%libiconv%&, you should add
1777 .code
1778 HAVE_ICONV=yes
1779 .endd
1780 to your &_Local/Makefile_& and rebuild Exim.
1784 .section "Including TLS/SSL encryption support" "SECTinctlsssl"
1785 .cindex "TLS" "including support for TLS"
1786 .cindex "encryption" "including support for"
1787 .cindex "SUPPORT_TLS"
1788 .cindex "OpenSSL" "building Exim with"
1789 .cindex "GnuTLS" "building Exim with"
1790 Exim can be built to support encrypted SMTP connections, using the STARTTLS
1791 command as per RFC 2487. It can also support legacy clients that expect to
1792 start a TLS session immediately on connection to a non-standard port (see the
1793 &%tls_on_connect_ports%& runtime option and the &%-tls-on-connect%& command
1794 line option).
1796 If you want to build Exim with TLS support, you must first install either the
1797 OpenSSL or GnuTLS library. There is no cryptographic code in Exim itself for
1798 implementing SSL.
1800 If OpenSSL is installed, you should set
1801 .code
1802 SUPPORT_TLS=yes
1803 TLS_LIBS=-lssl -lcrypto
1804 .endd
1805 in &_Local/Makefile_&. You may also need to specify the locations of the
1806 OpenSSL library and include files. For example:
1807 .code
1808 SUPPORT_TLS=yes
1809 TLS_LIBS=-L/usr/local/openssl/lib -lssl -lcrypto
1810 TLS_INCLUDE=-I/usr/local/openssl/include/
1811 .endd
1812 .cindex "USE_GNUTLS"
1813 If GnuTLS is installed, you should set
1814 .code
1815 SUPPORT_TLS=yes
1816 USE_GNUTLS=yes
1817 TLS_LIBS=-lgnutls -ltasn1 -lgcrypt
1818 .endd
1819 in &_Local/Makefile_&, and again you may need to specify the locations of the
1820 library and include files. For example:
1821 .code
1822 SUPPORT_TLS=yes
1823 USE_GNUTLS=yes
1824 TLS_LIBS=-L/usr/gnu/lib -lgnutls -ltasn1 -lgcrypt
1825 TLS_INCLUDE=-I/usr/gnu/include
1826 .endd
1827 You do not need to set TLS_INCLUDE if the relevant directory is already
1828 specified in INCLUDE. Details of how to configure Exim to make use of TLS are
1829 given in chapter &<<CHAPTLS>>&.
1834 .section "Use of tcpwrappers"
1835 .cindex "tcpwrappers" "building Exim to support"
1836 .cindex "USE_TCP_WRAPPERS"
1837 Exim can be linked with the &'tcpwrappers'& library in order to check incoming
1838 SMTP calls using the &'tcpwrappers'& control files. This may be a convenient
1839 alternative to Exim's own checking facilities for installations that are
1840 already making use of &'tcpwrappers'& for other purposes. To do this, you
1841 should set USE_TCP_WRAPPERS in &_Local/Makefile_&, arrange for the file
1842 &_tcpd.h_& to be available at compile time, and also ensure that the library
1843 &_libwrap.a_& is available at link time, typically by including &%-lwrap%& in
1844 EXTRALIBS_EXIM. For example, if &'tcpwrappers'& is installed in &_/usr/local_&,
1845 you might have
1846 .code
1848 CFLAGS=-O -I/usr/local/include
1849 EXTRALIBS_EXIM=-L/usr/local/lib -lwrap
1850 .endd
1851 in &_Local/Makefile_&. The name to use in the &'tcpwrappers'& control files is
1852 &"exim"&. For example, the line
1853 .code
1854 exim : LOCAL 192.168.1. .friendly.domain.example
1855 .endd
1856 in your &_/etc/hosts.allow_& file allows connections from the local host, from
1857 the subnet, and from all hosts in &'friendly.domain.example'&.
1858 All other connections are denied. Consult the &'tcpwrappers'& documentation for
1859 further details.
1863 .section "Including support for IPv6"
1864 .cindex "IPv6" "including support for"
1865 Exim contains code for use on systems that have IPv6 support. Setting
1866 &`HAVE_IPV6=YES`& in &_Local/Makefile_& causes the IPv6 code to be included;
1867 it may also be necessary to set IPV6_INCLUDE and IPV6_LIBS on systems
1868 where the IPv6 support is not fully integrated into the normal include and
1869 library files.
1871 Two different types of DNS record for handling IPv6 addresses have been
1872 defined. AAAA records (analagous to A records for IPv4) are in use, and are
1873 currently seen as the mainstream. Another record type called A6 was proposed
1874 as better than AAAA because it had more flexibility. However, it was felt to be
1875 over-complex, and its status was reduced to &"experimental"&. It is not known
1876 if anyone is actually using A6 records. Exim has support for A6 records, but
1877 this is included only if you set &`SUPPORT_A6=YES`& in &_Local/Makefile_&. The
1878 support has not been tested for some time.
1882 .section "The building process"
1883 .cindex "build directory"
1884 Once &_Local/Makefile_& (and &_Local/eximon.conf_&, if required) have been
1885 created, run &'make'& at the top level. It determines the architecture and
1886 operating system types, and creates a build directory if one does not exist.
1887 For example, on a Sun system running Solaris 8, the directory
1888 &_build-SunOS5-5.8-sparc_& is created.
1889 .cindex "symbolic link" "to source files"
1890 Symbolic links to relevant source files are installed in the build directory.
1892 &*Warning*&: The &%-j%& (parallel) flag must not be used with &'make'&; the
1893 building process fails if it is set.
1895 If this is the first time &'make'& has been run, it calls a script that builds
1896 a make file inside the build directory, using the configuration files from the
1897 &_Local_& directory. The new make file is then passed to another instance of
1898 &'make'&. This does the real work, building a number of utility scripts, and
1899 then compiling and linking the binaries for the Exim monitor (if configured), a
1900 number of utility programs, and finally Exim itself. The command &`make
1901 makefile`& can be used to force a rebuild of the make file in the build
1902 directory, should this ever be necessary.
1904 If you have problems building Exim, check for any comments there may be in the
1905 &_README_& file concerning your operating system, and also take a look at the
1906 FAQ, where some common problems are covered.
1910 .section 'Output from &"make"&'
1911 The output produced by the &'make'& process for compile lines is often very
1912 unreadable, because these lines can be very long. For this reason, the normal
1913 output is suppressed by default, and instead output similar to that which
1914 appears when compiling the 2.6 Linux kernel is generated: just a short line for
1915 each module that is being compiled or linked. However, it is still possible to
1916 get the full output, by calling &'make'& like this:
1917 .code
1918 FULLECHO='' make -e
1919 .endd
1920 The value of FULLECHO defaults to &"@"&, the flag character that suppresses
1921 command reflection in &'make'&. When you ask for the full output, it is
1922 given in addition to the the short output.
1926 .section "Overriding build-time options for Exim" "SECToverride"
1927 .cindex "build-time options" "overriding"
1928 The main make file that is created at the beginning of the building process
1929 consists of the concatenation of a number of files which set configuration
1930 values, followed by a fixed set of &'make'& instructions. If a value is set
1931 more than once, the last setting overrides any previous ones. This provides a
1932 convenient way of overriding defaults. The files that are concatenated are, in
1933 order:
1934 .display
1935 &_OS/Makefile-Default_&
1936 &_OS/Makefile-_&<&'ostype'&>
1937 &_Local/Makefile_&
1938 &_Local/Makefile-_&<&'ostype'&>
1939 &_Local/Makefile-_&<&'archtype'&>
1940 &_Local/Makefile-_&<&'ostype'&>-<&'archtype'&>
1941 &_OS/Makefile-Base_&
1942 .endd
1943 .cindex "&_Local/Makefile_&"
1944 .cindex "building Exim" "operating system type"
1945 .cindex "building Exim" "architecture type"
1946 where <&'ostype'&> is the operating system type and <&'archtype'&> is the
1947 architecture type. &_Local/Makefile_& is required to exist, and the building
1948 process fails if it is absent. The other three &_Local_& files are optional,
1949 and are often not needed.
1951 The values used for <&'ostype'&> and <&'archtype'&> are obtained from scripts
1952 called &_scripts/os-type_& and &_scripts/arch-type_& respectively. If either of
1953 the environment variables EXIM_OSTYPE or EXIM_ARCHTYPE is set, their
1954 values are used, thereby providing a means of forcing particular settings.
1955 Otherwise, the scripts try to get values from the &%uname%& command. If this
1956 fails, the shell variables OSTYPE and ARCHTYPE are inspected. A number
1957 of &'ad hoc'& transformations are then applied, to produce the standard names
1958 that Exim expects. You can run these scripts directly from the shell in order
1959 to find out what values are being used on your system.
1962 &_OS/Makefile-Default_& contains comments about the variables that are set
1963 therein. Some (but not all) are mentioned below. If there is something that
1964 needs changing, review the contents of this file and the contents of the make
1965 file for your operating system (&_OS/Makefile-<ostype>_&) to see what the
1966 default values are.
1969 .cindex "building Exim" "overriding default settings"
1970 If you need to change any of the values that are set in &_OS/Makefile-Default_&
1971 or in &_OS/Makefile-<ostype>_&, or to add any new definitions, you do not
1972 need to change the original files. Instead, you should make the changes by
1973 putting the new values in an appropriate &_Local_& file. For example,
1974 .cindex "Tru64-Unix build-time settings"
1975 when building Exim in many releases of the Tru64-Unix (formerly Digital UNIX,
1976 formerly DEC-OSF1) operating system, it is necessary to specify that the C
1977 compiler is called &'cc'& rather than &'gcc'&. Also, the compiler must be
1978 called with the option &%-std1%&, to make it recognize some of the features of
1979 Standard C that Exim uses. (Most other compilers recognize Standard C by
1980 default.) To do this, you should create a file called &_Local/Makefile-OSF1_&
1981 containing the lines
1982 .code
1983 CC=cc
1984 CFLAGS=-std1
1985 .endd
1986 If you are compiling for just one operating system, it may be easier to put
1987 these lines directly into &_Local/Makefile_&.
1989 Keeping all your local configuration settings separate from the distributed
1990 files makes it easy to transfer them to new versions of Exim simply by copying
1991 the contents of the &_Local_& directory.
1994 .cindex "NIS lookup type" "including support for"
1995 .cindex "NIS+ lookup type" "including support for"
1996 .cindex "LDAP" "including support for"
1997 .cindex "lookup" "inclusion in binary"
1998 Exim contains support for doing LDAP, NIS, NIS+, and other kinds of file
1999 lookup, but not all systems have these components installed, so the default is
2000 not to include the relevant code in the binary. All the different kinds of file
2001 and database lookup that Exim supports are implemented as separate code modules
2002 which are included only if the relevant compile-time options are set. In the
2003 case of LDAP, NIS, and NIS+, the settings for &_Local/Makefile_& are:
2004 .code
2005 LOOKUP_LDAP=yes
2006 LOOKUP_NIS=yes
2008 .endd
2009 and similar settings apply to the other lookup types. They are all listed in
2010 &_src/EDITME_&. In many cases the relevant include files and interface
2011 libraries need to be installed before compiling Exim.
2012 .cindex "cdb" "including support for"
2013 However, there are some optional lookup types (such as cdb) for which
2014 the code is entirely contained within Exim, and no external include
2015 files or libraries are required. When a lookup type is not included in the
2016 binary, attempts to configure Exim to use it cause run time configuration
2017 errors.
2019 .cindex "Perl" "including support for"
2020 Exim can be linked with an embedded Perl interpreter, allowing Perl
2021 subroutines to be called during string expansion. To enable this facility,
2022 .code
2023 EXIM_PERL=perl.o
2024 .endd
2025 must be defined in &_Local/Makefile_&. Details of this facility are given in
2026 chapter &<<CHAPperl>>&.
2028 .cindex "X11 libraries" "location of"
2029 The location of the X11 libraries is something that varies a lot between
2030 operating systems, and there may be different versions of X11 to cope
2031 with. Exim itself makes no use of X11, but if you are compiling the Exim
2032 monitor, the X11 libraries must be available.
2033 The following three variables are set in &_OS/Makefile-Default_&:
2034 .code
2035 X11=/usr/X11R6
2036 XINCLUDE=-I$(X11)/include
2037 XLFLAGS=-L$(X11)/lib
2038 .endd
2039 These are overridden in some of the operating-system configuration files. For
2040 example, in &_OS/Makefile-SunOS5_& there is
2041 .code
2042 X11=/usr/openwin
2043 XINCLUDE=-I$(X11)/include
2044 XLFLAGS=-L$(X11)/lib -R$(X11)/lib
2045 .endd
2046 If you need to override the default setting for your operating system, place a
2047 definition of all three of these variables into your
2048 &_Local/Makefile-<ostype>_& file.
2050 .cindex "EXTRALIBS"
2051 If you need to add any extra libraries to the link steps, these can be put in a
2052 variable called EXTRALIBS, which appears in all the link commands, but by
2053 default is not defined. In contrast, EXTRALIBS_EXIM is used only on the
2054 command for linking the main Exim binary, and not for any associated utilities.
2056 .cindex "DBM libraries" "configuration for building"
2057 There is also DBMLIB, which appears in the link commands for binaries that
2058 use DBM functions (see also section &<<SECTdb>>&). Finally, there is
2059 EXTRALIBS_EXIMON, which appears only in the link step for the Exim monitor
2060 binary, and which can be used, for example, to include additional X11
2061 libraries.
2063 .cindex "configuration file" "editing"
2064 The make file copes with rebuilding Exim correctly if any of the configuration
2065 files are edited. However, if an optional configuration file is deleted, it is
2066 necessary to touch the associated non-optional file (that is,
2067 &_Local/Makefile_& or &_Local/eximon.conf_&) before rebuilding.
2070 .section "OS-specific header files"
2071 .cindex "&_os.h_&"
2072 .cindex "building Exim" "OS-specific C header files"
2073 The &_OS_& directory contains a number of files with names of the form
2074 &_os.h-<ostype>_&. These are system-specific C header files that should not
2075 normally need to be changed. There is a list of macro settings that are
2076 recognized in the file &_OS/os.configuring_&, which should be consulted if you
2077 are porting Exim to a new operating system.
2081 .section "Overriding build-time options for the monitor"
2082 .cindex "building Eximon" "overriding default options"
2083 A similar process is used for overriding things when building the Exim monitor,
2084 where the files that are involved are
2085 .display
2086 &_OS/eximon.conf-Default_&
2087 &_OS/eximon.conf-_&<&'ostype'&>
2088 &_Local/eximon.conf_&
2089 &_Local/eximon.conf-_&<&'ostype'&>
2090 &_Local/eximon.conf-_&<&'archtype'&>
2091 &_Local/eximon.conf-_&<&'ostype'&>-<&'archtype'&>
2092 .endd
2093 .cindex "&_Local/eximon.conf_&"
2094 As with Exim itself, the final three files need not exist, and in this case the
2095 &_OS/eximon.conf-<ostype>_& file is also optional. The default values in
2096 &_OS/eximon.conf-Default_& can be overridden dynamically by setting environment
2097 variables of the same name, preceded by EXIMON_. For example, setting
2098 EXIMON_LOG_DEPTH in the environment overrides the value of
2099 LOG_DEPTH at run time.
2100 .ecindex IIDbuex
2103 .section "Installing Exim binaries and scripts"
2104 .cindex "installing Exim"
2105 .cindex "BIN_DIRECTORY"
2106 The command &`make install`& runs the &(exim_install)& script with no
2107 arguments. The script copies binaries and utility scripts into the directory
2108 whose name is specified by the BIN_DIRECTORY setting in &_Local/Makefile_&.
2109 .cindex "setuid" "installing Exim with"
2110 The install script copies files only if they are newer than the files they are
2111 going to replace. The Exim binary is required to be owned by root and have the
2112 &'setuid'& bit set, for normal configurations. Therefore, you must run &`make
2113 install`& as root so that it can set up the Exim binary in this way. However, in
2114 some special situations (for example, if a host is doing no local deliveries)
2115 it may be possible to run Exim without making the binary setuid root (see
2116 chapter &<<CHAPsecurity>>& for details).
2118 .cindex "CONFIGURE_FILE"
2119 Exim's run time configuration file is named by the CONFIGURE_FILE setting
2120 in &_Local/Makefile_&. If this names a single file, and the file does not
2121 exist, the default configuration file &_src/configure.default_& is copied there
2122 by the installation script. If a run time configuration file already exists, it
2123 is left alone. If CONFIGURE_FILE is a colon-separated list, naming several
2124 alternative files, no default is installed.
2126 .cindex "system aliases file"
2127 .cindex "&_/etc/aliases_&"
2128 One change is made to the default configuration file when it is installed: the
2129 default configuration contains a router that references a system aliases file.
2130 The path to this file is set to the value specified by
2131 SYSTEM_ALIASES_FILE in &_Local/Makefile_& (&_/etc/aliases_& by default).
2132 If the system aliases file does not exist, the installation script creates it,
2133 and outputs a comment to the user.
2135 The created file contains no aliases, but it does contain comments about the
2136 aliases a site should normally have. Mail aliases have traditionally been
2137 kept in &_/etc/aliases_&. However, some operating systems are now using
2138 &_/etc/mail/aliases_&. You should check if yours is one of these, and change
2139 Exim's configuration if necessary.
2141 The default configuration uses the local host's name as the only local domain,
2142 and is set up to do local deliveries into the shared directory &_/var/mail_&,
2143 running as the local user. System aliases and &_.forward_& files in users' home
2144 directories are supported, but no NIS or NIS+ support is configured. Domains
2145 other than the name of the local host are routed using the DNS, with delivery
2146 over SMTP.
2148 It is possible to install Exim for special purposes (such as building a binary
2149 distribution) in a private part of the file system. You can do this by a
2150 command such as
2151 .code
2152 make DESTDIR=/some/directory/ install
2153 .endd
2154 This has the effect of pre-pending the specified directory to all the file
2155 paths, except the name of the system aliases file that appears in the default
2156 configuration. (If a default alias file is created, its name &'is'& modified.)
2157 For backwards compatibility, ROOT is used if DESTDIR is not set,
2158 but this usage is deprecated.
2160 .cindex "installing Exim" "what is not installed"
2161 Running &'make install'& does not copy the Exim 4 conversion script
2162 &'convert4r4'&, or the &'pcretest'& test program. You will probably run the
2163 first of these only once (if you are upgrading from Exim 3), and the second
2164 isn't really part of Exim. None of the documentation files in the &_doc_&
2165 directory are copied, except for the info files when you have set
2166 INFO_DIRECTORY, as described in section &<<SECTinsinfdoc>>& below.
2168 For the utility programs, old versions are renamed by adding the suffix &_.O_&
2169 to their names. The Exim binary itself, however, is handled differently. It is
2170 installed under a name that includes the version number and the compile number,
2171 for example &_exim-&version;-1_&. The script then arranges for a symbolic link
2172 called &_exim_& to point to the binary. If you are updating a previous version
2173 of Exim, the script takes care to ensure that the name &_exim_& is never absent
2174 from the directory (as seen by other processes).
2176 .cindex "installing Exim" "testing the script"
2177 If you want to see what the &'make install'& will do before running it for
2178 real, you can pass the &%-n%& option to the installation script by this
2179 command:
2180 .code
2181 make INSTALL_ARG=-n install
2182 .endd
2183 The contents of the variable INSTALL_ARG are passed to the installation
2184 script. You do not need to be root to run this test. Alternatively, you can run
2185 the installation script directly, but this must be from within the build
2186 directory. For example, from the top-level Exim directory you could use this
2187 command:
2188 .code
2189 (cd build-SunOS5-5.5.1-sparc; ../scripts/exim_install -n)
2190 .endd
2191 .cindex "installing Exim" "install script options"
2192 There are two other options that can be supplied to the installation script.
2194 .ilist
2195 &%-no_chown%& bypasses the call to change the owner of the installed binary
2196 to root, and the call to make it a setuid binary.
2197 .next
2198 &%-no_symlink%& bypasses the setting up of the symbolic link &_exim_& to the
2199 installed binary.
2200 .endlist
2202 INSTALL_ARG can be used to pass these options to the script. For example:
2203 .code
2204 make INSTALL_ARG=-no_symlink install
2205 .endd
2206 The installation script can also be given arguments specifying which files are
2207 to be copied. For example, to install just the Exim binary, and nothing else,
2208 without creating the symbolic link, you could use:
2209 .code
2210 make INSTALL_ARG='-no_symlink exim' install
2211 .endd
2215 .section "Installing info documentation" "SECTinsinfdoc"
2216 .cindex "installing Exim" "&'info'& documentation"
2217 Not all systems use the GNU &'info'& system for documentation, and for this
2218 reason, the Texinfo source of Exim's documentation is not included in the main
2219 distribution. Instead it is available separately from the ftp site (see section
2220 &<<SECTavail>>&).
2222 If you have defined INFO_DIRECTORY in &_Local/Makefile_& and the Texinfo
2223 source of the documentation is found in the source tree, running &`make
2224 install`& automatically builds the info files and installs them.
2228 .section "Setting up the spool directory"
2229 .cindex "spool directory" "creating"
2230 When it starts up, Exim tries to create its spool directory if it does not
2231 exist. The Exim uid and gid are used for the owner and group of the spool
2232 directory. Sub-directories are automatically created in the spool directory as
2233 necessary.
2238 .section "Testing"
2239 .cindex "testing" "installation"
2240 Having installed Exim, you can check that the run time configuration file is
2241 syntactically valid by running the following command, which assumes that the
2242 Exim binary directory is within your PATH environment variable:
2243 .code
2244 exim -bV
2245 .endd
2246 If there are any errors in the configuration file, Exim outputs error messages.
2247 Otherwise it outputs the version number and build date,
2248 the DBM library that is being used, and information about which drivers and
2249 other optional code modules are included in the binary.
2250 Some simple routing tests can be done by using the address testing option. For
2251 example,
2252 .display
2253 &`exim -bt`& <&'local username'&>
2254 .endd
2255 should verify that it recognizes a local mailbox, and
2256 .display
2257 &`exim -bt`& <&'remote address'&>
2258 .endd
2259 a remote one. Then try getting it to deliver mail, both locally and remotely.
2260 This can be done by passing messages directly to Exim, without going through a
2261 user agent. For example:
2262 .code
2263 exim -v postmaster@your.domain.example
2264 From: user@your.domain.example
2265 To: postmaster@your.domain.example
2266 Subject: Testing Exim
2268 This is a test message.
2269 ^D
2270 .endd
2271 The &%-v%& option causes Exim to output some verification of what it is doing.
2272 In this case you should see copies of three log lines, one for the message's
2273 arrival, one for its delivery, and one containing &"Completed"&.
2275 .cindex "delivery" "problems with"
2276 If you encounter problems, look at Exim's log files (&'mainlog'& and
2277 &'paniclog'&) to see if there is any relevant information there. Another source
2278 of information is running Exim with debugging turned on, by specifying the
2279 &%-d%& option. If a message is stuck on Exim's spool, you can force a delivery
2280 with debugging turned on by a command of the form
2281 .display
2282 &`exim -d -M`& <&'exim-message-id'&>
2283 .endd
2284 You must be root or an &"admin user"& in order to do this. The &%-d%& option
2285 produces rather a lot of output, but you can cut this down to specific areas.
2286 For example, if you use &%-d-all+route%& only the debugging information
2287 relevant to routing is included. (See the &%-d%& option in chapter
2288 &<<CHAPcommandline>>& for more details.)
2290 .cindex '&"sticky"& bit'
2291 .cindex "lock files"
2292 One specific problem that has shown up on some sites is the inability to do
2293 local deliveries into a shared mailbox directory, because it does not have the
2294 &"sticky bit"& set on it. By default, Exim tries to create a lock file before
2295 writing to a mailbox file, and if it cannot create the lock file, the delivery
2296 is deferred. You can get round this either by setting the &"sticky bit"& on the
2297 directory, or by setting a specific group for local deliveries and allowing
2298 that group to create files in the directory (see the comments above the
2299 &(local_delivery)& transport in the default configuration file). Another
2300 approach is to configure Exim not to use lock files, but just to rely on
2301 &[fcntl()]& locking instead. However, you should do this only if all user
2302 agents also use &[fcntl()]& locking. For further discussion of locking issues,
2303 see chapter &<<CHAPappendfile>>&.
2305 One thing that cannot be tested on a system that is already running an MTA is
2306 the receipt of incoming SMTP mail on the standard SMTP port. However, the
2307 &%-oX%& option can be used to run an Exim daemon that listens on some other
2308 port, or &'inetd'& can be used to do this. The &%-bh%& option and the
2309 &'exim_checkaccess'& utility can be used to check out policy controls on
2310 incoming SMTP mail.
2312 Testing a new version on a system that is already running Exim can most easily
2313 be done by building a binary with a different CONFIGURE_FILE setting. From
2314 within the run time configuration, all other file and directory names
2315 that Exim uses can be altered, in order to keep it entirely clear of the
2316 production version.
2319 .section "Replacing another MTA with Exim"
2320 .cindex "replacing another MTA"
2321 Building and installing Exim for the first time does not of itself put it in
2322 general use. The name by which the system's MTA is called by mail user agents
2323 is either &_/usr/sbin/sendmail_&, or &_/usr/lib/sendmail_& (depending on the
2324 operating system), and it is necessary to make this name point to the &'exim'&
2325 binary in order to get the user agents to pass messages to Exim. This is
2326 normally done by renaming any existing file and making &_/usr/sbin/sendmail_&
2327 or &_/usr/lib/sendmail_&
2328 .cindex "symbolic link" "to &'exim'& binary"
2329 a symbolic link to the &'exim'& binary. It is a good idea to remove any setuid
2330 privilege and executable status from the old MTA. It is then necessary to stop
2331 and restart the mailer daemon, if one is running.
2333 .cindex "FreeBSD" "MTA indirection"
2334 .cindex "&_/etc/mail/mailer.conf_&"
2335 Some operating systems have introduced alternative ways of switching MTAs. For
2336 example, if you are running FreeBSD, you need to edit the file
2337 &_/etc/mail/mailer.conf_& instead of setting up a symbolic link as just
2338 described. A typical example of the contents of this file for running Exim is
2339 as follows:
2340 .code
2341 sendmail /usr/exim/bin/exim
2342 send-mail /usr/exim/bin/exim
2343 mailq /usr/exim/bin/exim -bp
2344 newaliases /usr/bin/true
2345 .endd
2346 Once you have set up the symbolic link, or edited &_/etc/mail/mailer.conf_&,
2347 your Exim installation is &"live"&. Check it by sending a message from your
2348 favourite user agent.
2350 You should consider what to tell your users about the change of MTA. Exim may
2351 have different capabilities to what was previously running, and there are
2352 various operational differences such as the text of messages produced by
2353 command line options and in bounce messages. If you allow your users to make
2354 use of Exim's filtering capabilities, you should make the document entitled
2355 &'Exim's interface to mail filtering'& available to them.
2359 .section "Upgrading Exim"
2360 .cindex "upgrading Exim"
2361 If you are already running Exim on your host, building and installing a new
2362 version automatically makes it available to MUAs, or any other programs that
2363 call the MTA directly. However, if you are running an Exim daemon, you do need
2364 to send it a HUP signal, to make it re-execute itself, and thereby pick up the
2365 new binary. You do not need to stop processing mail in order to install a new
2366 version of Exim. The install script does not modify an existing runtime
2367 configuration file.
2372 .section "Stopping the Exim daemon on Solaris"
2373 .cindex "Solaris" "stopping Exim on"
2374 The standard command for stopping the mailer daemon on Solaris is
2375 .code
2376 /etc/init.d/sendmail stop
2377 .endd
2378 If &_/usr/lib/sendmail_& has been turned into a symbolic link, this script
2379 fails to stop Exim because it uses the command &'ps -e'& and greps the output
2380 for the text &"sendmail"&; this is not present because the actual program name
2381 (that is, &"exim"&) is given by the &'ps'& command with these options. A
2382 solution is to replace the line that finds the process id with something like
2383 .code
2384 pid=`cat /var/spool/exim/exim-daemon.pid`
2385 .endd
2386 to obtain the daemon's pid directly from the file that Exim saves it in.
2388 Note, however, that stopping the daemon does not &"stop Exim"&. Messages can
2389 still be received from local processes, and if automatic delivery is configured
2390 (the normal case), deliveries will still occur.
2395 . ////////////////////////////////////////////////////////////////////////////
2396 . ////////////////////////////////////////////////////////////////////////////
2398 .chapter "The Exim command line" "CHAPcommandline"
2399 .scindex IIDclo1 "command line" "options"
2400 .scindex IIDclo2 "options" "command line"
2401 Exim's command line takes the standard Unix form of a sequence of options,
2402 each starting with a hyphen character, followed by a number of arguments. The
2403 options are compatible with the main options of Sendmail, and there are also
2404 some additional options, some of which are compatible with Smail 3. Certain
2405 combinations of options do not make sense, and provoke an error if used.
2406 The form of the arguments depends on which options are set.
2409 .section "Setting options by program name"
2410 .cindex "&'mailq'&"
2411 If Exim is called under the name &'mailq'&, it behaves as if the option &%-bp%&
2412 were present before any other options.
2413 The &%-bp%& option requests a listing of the contents of the mail queue on the
2414 standard output.
2415 This feature is for compatibility with some systems that contain a command of
2416 that name in one of the standard libraries, symbolically linked to
2417 &_/usr/sbin/sendmail_& or &_/usr/lib/sendmail_&.
2419 .cindex "&'rsmtp'&"
2420 If Exim is called under the name &'rsmtp'& it behaves as if the option &%-bS%&
2421 were present before any other options, for compatibility with Smail. The
2422 &%-bS%& option is used for reading in a number of messages in batched SMTP
2423 format.
2425 .cindex "&'rmail'&"
2426 If Exim is called under the name &'rmail'& it behaves as if the &%-i%& and
2427 &%-oee%& options were present before any other options, for compatibility with
2428 Smail. The name &'rmail'& is used as an interface by some UUCP systems.
2430 .cindex "&'runq'&"
2431 .cindex "queue runner"
2432 If Exim is called under the name &'runq'& it behaves as if the option &%-q%&
2433 were present before any other options, for compatibility with Smail. The &%-q%&
2434 option causes a single queue runner process to be started.
2436 .cindex "&'newaliases'&"
2437 .cindex "alias file" "building"
2438 .cindex "Sendmail compatibility" "calling Exim as &'newaliases'&"
2439 If Exim is called under the name &'newaliases'& it behaves as if the option
2440 &%-bi%& were present before any other options, for compatibility with Sendmail.
2441 This option is used for rebuilding Sendmail's alias file. Exim does not have
2442 the concept of a single alias file, but can be configured to run a given
2443 command if called with the &%-bi%& option.
2446 .section "Trusted and admin users" "SECTtrustedadmin"
2447 Some Exim options are available only to &'trusted users'& and others are
2448 available only to &'admin users'&. In the description below, the phrases &"Exim
2449 user"& and &"Exim group"& mean the user and group defined by EXIM_USER and
2450 EXIM_GROUP in &_Local/Makefile_& or set by the &%exim_user%& and
2451 &%exim_group%& options. These do not necessarily have to use the name &"exim"&.
2453 .ilist
2454 .cindex "trusted user" "definition of"
2455 .cindex "user" "trusted definition of"
2456 The trusted users are root, the Exim user, any user listed in the
2457 &%trusted_users%& configuration option, and any user whose current group or any
2458 supplementary group is one of those listed in the &%trusted_groups%&
2459 configuration option. Note that the Exim group is not automatically trusted.
2461 .cindex '&"From"& line'
2462 .cindex "envelope sender"
2463 Trusted users are always permitted to use the &%-f%& option or a leading
2464 &"From&~"& line to specify the envelope sender of a message that is passed to
2465 Exim through the local interface (see the &%-bm%& and &%-f%& options below).
2466 See the &%untrusted_set_sender%& option for a way of permitting non-trusted
2467 users to set envelope senders.
2469 .cindex "&'From:'& header line"
2470 .cindex "&'Sender:'& header line"
2471 For a trusted user, there is never any check on the contents of the &'From:'&
2472 header line, and a &'Sender:'& line is never added. Furthermore, any existing
2473 &'Sender:'& line in incoming local (non-TCP/IP) messages is not removed.
2475 Trusted users may also specify a host name, host address, interface address,
2476 protocol name, ident value, and authentication data when submitting a message
2477 locally. Thus, they are able to insert messages into Exim's queue locally that
2478 have the characteristics of messages received from a remote host. Untrusted
2479 users may in some circumstances use &%-f%&, but can never set the other values
2480 that are available to trusted users.
2481 .next
2482 .cindex "user" "admin definition of"
2483 .cindex "admin user" "definition of"
2484 The admin users are root, the Exim user, and any user that is a member of the
2485 Exim group or of any group listed in the &%admin_groups%& configuration option.
2486 The current group does not have to be one of these groups.
2488 Admin users are permitted to list the queue, and to carry out certain
2489 operations on messages, for example, to force delivery failures. It is also
2490 necessary to be an admin user in order to see the full information provided by
2491 the Exim monitor, and full debugging output.
2493 By default, the use of the &%-M%&, &%-q%&, &%-R%&, and &%-S%& options to cause
2494 Exim to attempt delivery of messages on its queue is restricted to admin users.
2495 However, this restriction can be relaxed by setting the &%prod_requires_admin%&
2496 option false (that is, specifying &%no_prod_requires_admin%&).
2498 Similarly, the use of the &%-bp%& option to list all the messages in the queue
2499 is restricted to admin users unless &%queue_list_requires_admin%& is set
2500 false.
2501 .endlist
2504 &*Warning*&: If you configure your system so that admin users are able to
2505 edit Exim's configuration file, you are giving those users an easy way of
2506 getting root. There is further discussion of this issue at the start of chapter
2507 &<<CHAPconf>>&.
2512 .section "Command line options"
2513 The command options are described in alphabetical order below.
2515 . ////////////////////////////////////////////////////////////////////////////
2516 . Insert a stylized XML comment here, to identify the start of the command line
2517 . options. This is for the benefit of the Perl script that automatically
2518 . creates a man page for the options.
2519 . ////////////////////////////////////////////////////////////////////////////
2521 .literal xml
2522 <!-- === Start of command line options === -->
2523 .literal off
2526 .vlist
2527 .vitem &%--%&
2528 .oindex "--"
2529 .cindex "options" "command line; terminating"
2530 This is a pseudo-option whose only purpose is to terminate the options and
2531 therefore to cause subsequent command line items to be treated as arguments
2532 rather than options, even if they begin with hyphens.
2534 .vitem &%--help%&
2535 .oindex "&%--help%&"
2536 This option causes Exim to output a few sentences stating what it is.
2537 The same output is generated if the Exim binary is called with no options and
2538 no arguments.
2540 .vitem &%-B%&<&'type'&>
2541 .oindex "&%-B%&"
2542 .cindex "8-bit characters"
2543 .cindex "Sendmail compatibility" "8-bit characters"
2544 This is a Sendmail option for selecting 7 or 8 bit processing. Exim is 8-bit
2545 clean; it ignores this option.
2547 .vitem &%-bd%&
2548 .oindex "&%-bd%&"
2549 .cindex "daemon"
2550 .cindex "SMTP listener"
2551 .cindex "queue runner"
2552 This option runs Exim as a daemon, awaiting incoming SMTP connections. Usually
2553 the &%-bd%& option is combined with the &%-q%&<&'time'&> option, to specify
2554 that the daemon should also initiate periodic queue runs.
2556 The &%-bd%& option can be used only by an admin user. If either of the &%-d%&
2557 (debugging) or &%-v%& (verifying) options are set, the daemon does not
2558 disconnect from the controlling terminal. When running this way, it can be
2559 stopped by pressing ctrl-C.
2561 By default, Exim listens for incoming connections to the standard SMTP port on
2562 all the host's running interfaces. However, it is possible to listen on other
2563 ports, on multiple ports, and only on specific interfaces. Chapter
2564 &<<CHAPinterfaces>>& contains a description of the options that control this.
2566 When a listening daemon
2567 .cindex "daemon" "process id (pid)"
2568 .cindex "pid (process id)" "of daemon"
2569 is started without the use of &%-oX%& (that is, without overriding the normal
2570 configuration), it writes its process id to a file called &_exim-daemon.pid_&
2571 in Exim's spool directory. This location can be overridden by setting
2572 PID_FILE_PATH in &_Local/Makefile_&. The file is written while Exim is still
2573 running as root.
2575 When &%-oX%& is used on the command line to start a listening daemon, the
2576 process id is not written to the normal pid file path. However, &%-oP%& can be
2577 used to specify a path on the command line if a pid file is required.
2579 The SIGHUP signal
2580 .cindex "SIGHUP"
2581 can be used to cause the daemon to re-exec itself. This should be done whenever
2582 Exim's configuration file, or any file that is incorporated into it by means of
2583 the &%.include%& facility, is changed, and also whenever a new version of Exim
2584 is installed. It is not necessary to do this when other files that are
2585 referenced from the configuration (for example, alias files) are changed,
2586 because these are reread each time they are used.
2588 .vitem &%-bdf%&
2589 .oindex "&%-bdf%&"
2590 This option has the same effect as &%-bd%& except that it never disconnects
2591 from the controlling terminal, even when no debugging is specified.
2593 .vitem &%-be%&
2594 .oindex "&%-be%&"
2595 .cindex "testing" "string expansion"
2596 .cindex "expansion" "testing"
2597 Run Exim in expansion testing mode. Exim discards its root privilege, to
2598 prevent ordinary users from using this mode to read otherwise inaccessible
2599 files. If no arguments are given, Exim runs interactively, prompting for lines
2600 of data. Otherwise, it processes each argument in turn.
2602 If Exim was built with USE_READLINE=yes in &_Local/Makefile_&, it tries
2603 to load the &%libreadline%& library dynamically whenever the &%-be%& option is
2604 used without command line arguments. If successful, it uses the &[readline()]&
2605 function, which provides extensive line-editing facilities, for reading the
2606 test data. A line history is supported.
2608 Long expansion expressions can be split over several lines by using backslash
2609 continuations. As in Exim's run time configuration, white space at the start of
2610 continuation lines is ignored. Each argument or data line is passed through the
2611 string expansion mechanism, and the result is output. Variable values from the
2612 configuration file (for example, &$qualify_domain$&) are available, but no
2613 message-specific values (such as &$domain$&) are set, because no message is
2614 being processed.
2616 &*Note*&: If you use this mechanism to test lookups, and you change the data
2617 files or databases you are using, you must exit and restart Exim before trying
2618 the same lookup again. Otherwise, because each Exim process caches the results
2619 of lookups, you will just get the same result as before.
2621 .vitem &%-bF%&&~<&'filename'&>
2622 .oindex "&%-bF%&"
2623 .cindex "system filter" "testing"
2624 .cindex "testing" "system filter"
2625 This option is the same as &%-bf%& except that it assumes that the filter being
2626 tested is a system filter. The additional commands that are available only in
2627 system filters are recognized.
2629 .vitem &%-bf%&&~<&'filename'&>
2630 .oindex "&%-bf%&"
2631 .cindex "filter" "testing"
2632 .cindex "testing" "filter file"
2633 .cindex "forward file" "testing"
2634 .cindex "testing" "forward file"
2635 .cindex "Sieve filter" "testing"
2636 This option runs Exim in user filter testing mode; the file is the filter file
2637 to be tested, and a test message must be supplied on the standard input. If
2638 there are no message-dependent tests in the filter, an empty file can be
2639 supplied.
2641 If you want to test a system filter file, use &%-bF%& instead of &%-bf%&. You
2642 can use both &%-bF%& and &%-bf%& on the same command, in order to test a system
2643 filter and a user filter in the same run. For example:
2644 .code
2645 exim -bF /system/filter -bf /user/filter </test/message
2646 .endd
2647 This is helpful when the system filter adds header lines or sets filter
2648 variables that are used by the user filter.
2650 If the test filter file does not begin with one of the special lines
2651 .code
2652 # Exim filter
2653 # Sieve filter
2654 .endd
2655 it is taken to be a normal &_.forward_& file, and is tested for validity under
2656 that interpretation. See sections &<<SECTitenonfilred>>& to
2657 &<<SECTspecitredli>>& for a description of the possible contents of non-filter
2658 redirection lists.
2660 The result of an Exim command that uses &%-bf%&, provided no errors are
2661 detected, is a list of the actions that Exim would try to take if presented
2662 with the message for real. More details of filter testing are given in the
2663 separate document entitled &'Exim's interfaces to mail filtering'&.
2665 When testing a filter file,
2666 .cindex "&""From""& line"
2667 .cindex "envelope sender"
2668 .cindex "&%-f%& option" "for filter testing"
2669 the envelope sender can be set by the &%-f%& option,
2670 or by a &"From&~"& line at the start of the test message. Various parameters
2671 that would normally be taken from the envelope recipient address of the message
2672 can be set by means of additional command line options (see the next four
2673 options).
2675 .vitem &%-bfd%&&~<&'domain'&>
2676 .oindex "&%-bfd%&"
2677 .cindex "&$qualify_domain$&"
2678 This sets the domain of the recipient address when a filter file is being
2679 tested by means of the &%-bf%& option. The default is the value of
2680 &$qualify_domain$&.
2682 .vitem &%-bfl%&&~<&'local&~part'&>
2683 .oindex "&%-bfl%&"
2684 This sets the local part of the recipient address when a filter file is being
2685 tested by means of the &%-bf%& option. The default is the username of the
2686 process that calls Exim. A local part should be specified with any prefix or
2687 suffix stripped, because that is how it appears to the filter when a message is
2688 actually being delivered.
2690 .vitem &%-bfp%&&~<&'prefix'&>
2691 .oindex "&%-bfp%&"
2692 This sets the prefix of the local part of the recipient address when a filter
2693 file is being tested by means of the &%-bf%& option. The default is an empty
2694 prefix.
2696 .vitem &%-bfs%&&~<&'suffix'&>
2697 .oindex "&%-bfs%&"
2698 This sets the suffix of the local part of the recipient address when a filter
2699 file is being tested by means of the &%-bf%& option. The default is an empty
2700 suffix.
2702 .vitem &%-bh%&&~<&'IP&~address'&>
2703 .oindex "&%-bh%&"
2704 .cindex "testing" "incoming SMTP"
2705 .cindex "SMTP" "testing incoming"
2706 .cindex "testing" "relay control"
2707 .cindex "relaying" "testing configuration"
2708 .cindex "policy control" "testing"
2709 .cindex "debugging" "&%-bh%& option"
2710 This option runs a fake SMTP session as if from the given IP address, using the
2711 standard input and output. The IP address may include a port number at the end,
2712 after a full stop. For example:
2713 .code
2714 exim -bh
2715 exim -bh fe80::a00:20ff:fe86:a061.5678
2716 .endd
2717 When an IPv6 address is given, it is converted into canonical form. In the case
2718 of the second example above, the value of &$sender_host_address$& after
2719 conversion to the canonical form is
2720 &`fe80:0000:0000:0a00:20ff:fe86:a061.5678`&.
2722 Comments as to what is going on are written to the standard error file. These
2723 include lines beginning with &"LOG"& for anything that would have been logged.
2724 This facility is provided for testing configuration options for incoming
2725 messages, to make sure they implement the required policy. For example, you can
2726 test your relay controls using &%-bh%&.
2728 &*Warning 1*&:
2729 .cindex "RFC 1413"
2730 You cannot test features of the configuration that rely on
2731 ident (RFC 1413) callouts. These cannot be done when testing using
2732 &%-bh%& because there is no incoming SMTP connection.
2734 &*Warning 2*&: Address verification callouts (see section &<<SECTcallver>>&)
2735 are also skipped when testing using &%-bh%&. If you want these callouts to
2736 occur, use &%-bhc%& instead.
2738 Messages supplied during the testing session are discarded, and nothing is
2739 written to any of the real log files. There may be pauses when DNS (and other)
2740 lookups are taking place, and of course these may time out. The &%-oMi%& option
2741 can be used to specify a specific IP interface and port if this is important.
2743 The &'exim_checkaccess'& utility is a &"packaged"& version of &%-bh%& whose
2744 output just states whether a given recipient address from a given host is
2745 acceptable or not. See section &<<SECTcheckaccess>>&.
2747 .vitem &%-bhc%&&~<&'IP&~address'&>
2748 .oindex "&%-bhc%&"
2749 This option operates in the same way as &%-bh%&, except that address
2750 verification callouts are performed if required. This includes consulting and
2751 updating the callout cache database.
2753 .vitem &%-bi%&
2754 .oindex "&%-bi%&"
2755 .cindex "alias file" "building"
2756 .cindex "building alias file"
2757 .cindex "Sendmail compatibility" "&%-bi%& option"
2758 Sendmail interprets the &%-bi%& option as a request to rebuild its alias file.
2759 Exim does not have the concept of a single alias file, and so it cannot mimic
2760 this behaviour. However, calls to &_/usr/lib/sendmail_& with the &%-bi%& option
2761 tend to appear in various scripts such as NIS make files, so the option must be
2762 recognized.
2764 If &%-bi%& is encountered, the command specified by the &%bi_command%&
2765 configuration option is run, under the uid and gid of the caller of Exim. If
2766 the &%-oA%& option is used, its value is passed to the command as an argument.
2767 The command set by &%bi_command%& may not contain arguments. The command can
2768 use the &'exim_dbmbuild'& utility, or some other means, to rebuild alias files
2769 if this is required. If the &%bi_command%& option is not set, calling Exim with
2770 &%-bi%& is a no-op.
2772 .vitem &%-bm%&
2773 .oindex "&%-bm%&"
2774 .cindex "local message reception"
2775 This option runs an Exim receiving process that accepts an incoming,
2776 locally-generated message on the current input. The recipients are given as the
2777 command arguments (except when &%-t%& is also present &-- see below). Each
2778 argument can be a comma-separated list of RFC 2822 addresses. This is the
2779 default option for selecting the overall action of an Exim call; it is assumed
2780 if no other conflicting option is present.
2782 If any addresses in the message are unqualified (have no domain), they are
2783 qualified by the values of the &%qualify_domain%& or &%qualify_recipient%&
2784 options, as appropriate. The &%-bnq%& option (see below) provides a way of
2785 suppressing this for special cases.
2787 Policy checks on the contents of local messages can be enforced by means of
2788 the non-SMTP ACL. See chapter &<<CHAPACL>>& for details.
2790 .cindex "return code" "for &%-bm%&"
2791 The return code is zero if the message is successfully accepted. Otherwise, the
2792 action is controlled by the &%-oe%&&'x'& option setting &-- see below.
2794 The format
2795 .cindex "message" "format"
2796 .cindex "format" "message"
2797 .cindex "&""From""& line"
2798 .cindex "UUCP" "&""From""& line"
2799 .cindex "Sendmail compatibility" "&""From""& line"
2800 of the message must be as defined in RFC 2822, except that, for
2801 compatibility with Sendmail and Smail, a line in one of the forms
2802 .code
2803 From sender Fri Jan 5 12:55 GMT 1997
2804 From sender Fri, 5 Jan 97 12:55:01
2805 .endd
2806 (with the weekday optional, and possibly with additional text after the date)
2807 is permitted to appear at the start of the message. There appears to be no
2808 authoritative specification of the format of this line. Exim recognizes it by
2809 matching against the regular expression defined by the &%uucp_from_pattern%&
2810 option, which can be changed if necessary.
2812 The
2813 .cindex "&%-f%& option" "overriding &""From""& line"
2814 specified sender is treated as if it were given as the argument to the
2815 &%-f%& option, but if a &%-f%& option is also present, its argument is used in
2816 preference to the address taken from the message. The caller of Exim must be a
2817 trusted user for the sender of a message to be set in this way.
2819 .vitem &%-bnq%&
2820 .oindex "&%-bnq%&"
2821 .cindex "address qualification" "suppressing"
2822 By default, Exim automatically qualifies unqualified addresses (those
2823 without domains) that appear in messages that are submitted locally (that
2824 is, not over TCP/IP). This qualification applies both to addresses in
2825 envelopes, and addresses in header lines. Sender addresses are qualified using
2826 &%qualify_domain%&, and recipient addresses using &%qualify_recipient%& (which
2827 defaults to the value of &%qualify_domain%&).
2829 Sometimes, qualification is not wanted. For example, if &%-bS%& (batch SMTP) is
2830 being used to re-submit messages that originally came from remote hosts after
2831 content scanning, you probably do not want to qualify unqualified addresses in
2832 header lines. (Such lines will be present only if you have not enabled a header
2833 syntax check in the appropriate ACL.)
2835 The &%-bnq%& option suppresses all qualification of unqualified addresses in
2836 messages that originate on the local host. When this is used, unqualified
2837 addresses in the envelope provoke errors (causing message rejection) and
2838 unqualified addresses in header lines are left alone.
2841 .vitem &%-bP%&
2842 .oindex "&%-bP%&"
2843 .cindex "configuration options" "extracting"
2844 .cindex "options" "configuration &-- extracting"
2845 If this option is given with no arguments, it causes the values of all Exim's
2846 main configuration options to be written to the standard output. The values
2847 of one or more specific options can be requested by giving their names as
2848 arguments, for example:
2849 .code
2850 exim -bP qualify_domain hold_domains
2851 .endd
2852 However, any option setting that is preceded by the word &"hide"& in the
2853 configuration file is not shown in full, except to an admin user. For other
2854 users, the output is as in this example:
2855 .code
2856 mysql_servers = <value not displayable>
2857 .endd
2858 If &%configure_file%& is given as an argument, the name of the run time
2859 configuration file is output.
2860 If a list of configuration files was supplied, the value that is output here
2861 is the name of the file that was actually used.
2863 .cindex "daemon" "process id (pid)"
2864 .cindex "pid (process id)" "of daemon"
2865 If &%log_file_path%& or &%pid_file_path%& are given, the names of the
2866 directories where log files and daemon pid files are written are output,
2867 respectively. If these values are unset, log files are written in a
2868 sub-directory of the spool directory called &%log%&, and the pid file is
2869 written directly into the spool directory.
2871 If &%-bP%& is followed by a name preceded by &`+`&, for example,
2872 .code
2873 exim -bP +local_domains
2874 .endd
2875 it searches for a matching named list of any type (domain, host, address, or
2876 local part) and outputs what it finds.
2878 .cindex "options" "router &-- extracting"
2879 .cindex "options" "transport &-- extracting"
2880 If one of the words &%router%&, &%transport%&, or &%authenticator%& is given,
2881 followed by the name of an appropriate driver instance, the option settings for
2882 that driver are output. For example:
2883 .code
2884 exim -bP transport local_delivery
2885 .endd
2886 The generic driver options are output first, followed by the driver's private
2887 options. A list of the names of drivers of a particular type can be obtained by
2888 using one of the words &%router_list%&, &%transport_list%&, or
2889 &%authenticator_list%&, and a complete list of all drivers with their option
2890 settings can be obtained by using &%routers%&, &%transports%&, or
2891 &%authenticators%&.
2894 .vitem &%-bp%&
2895 .oindex "&%-bp%&"
2896 .cindex "queue" "listing messages on"
2897 .cindex "listing" "messages on the queue"
2898 This option requests a listing of the contents of the mail queue on the
2899 standard output. If the &%-bp%& option is followed by a list of message ids,
2900 just those messages are listed. By default, this option can be used only by an
2901 admin user. However, the &%queue_list_requires_admin%& option can be set false
2902 to allow any user to see the queue.
2904 Each message on the queue is displayed as in the following example:
2905 .code
2906 25m 2.9K 0t5C6f-0000c8-00 <alice@wonderland.fict.example>
2907 red.king@looking-glass.fict.example
2908 <other addresses>
2909 .endd
2910 .cindex "message" "size in queue listing"
2911 .cindex "size" "of message"
2912 The first line contains the length of time the message has been on the queue
2913 (in this case 25 minutes), the size of the message (2.9K), the unique local
2914 identifier for the message, and the message sender, as contained in the
2915 envelope. For bounce messages, the sender address is empty, and appears as
2916 &"<>"&. If the message was submitted locally by an untrusted user who overrode
2917 the default sender address, the user's login name is shown in parentheses
2918 before the sender address.
2920 .cindex "frozen messages" "in queue listing"
2921 If the message is frozen (attempts to deliver it are suspended) then the text
2922 &"*** frozen ***"& is displayed at the end of this line.
2924 The recipients of the message (taken from the envelope, not the headers) are
2925 displayed on subsequent lines. Those addresses to which the message has already
2926 been delivered are marked with the letter D. If an original address gets
2927 expanded into several addresses via an alias or forward file, the original is
2928 displayed with a D only when deliveries for all of its child addresses are
2929 complete.
2932 .vitem &%-bpa%&
2933 .oindex "&%-bpa%&"
2934 This option operates like &%-bp%&, but in addition it shows delivered addresses
2935 that were generated from the original top level address(es) in each message by
2936 alias or forwarding operations. These addresses are flagged with &"+D"& instead
2937 of just &"D"&.
2940 .vitem &%-bpc%&
2941 .oindex "&%-bpc%&"
2942 .cindex "queue" "count of messages on"
2943 This option counts the number of messages on the queue, and writes the total
2944 to the standard output. It is restricted to admin users, unless
2945 &%queue_list_requires_admin%& is set false.
2948 .vitem &%-bpr%&
2949 .oindex "&%-bpr%&"
2950 This option operates like &%-bp%&, but the output is not sorted into
2951 chronological order of message arrival. This can speed it up when there are
2952 lots of messages on the queue, and is particularly useful if the output is
2953 going to be post-processed in a way that doesn't need the sorting.
2955 .vitem &%-bpra%&
2956 .oindex "&%-bpra%&"
2957 This option is a combination of &%-bpr%& and &%-bpa%&.
2959 .vitem &%-bpru%&
2960 .oindex "&%-bpru%&"
2961 This option is a combination of &%-bpr%& and &%-bpu%&.
2964 .vitem &%-bpu%&
2965 .oindex "&%-bpu%&"
2966 This option operates like &%-bp%& but shows only undelivered top-level
2967 addresses for each message displayed. Addresses generated by aliasing or
2968 forwarding are not shown, unless the message was deferred after processing by a
2969 router with the &%one_time%& option set.
2972 .vitem &%-brt%&
2973 .oindex "&%-brt%&"
2974 .cindex "testing" "retry configuration"
2975 .cindex "retry" "configuration testing"
2976 This option is for testing retry rules, and it must be followed by up to three
2977 arguments. It causes Exim to look for a retry rule that matches the values
2978 and to write it to the standard output. For example:
2979 .code
2980 exim -brt bach.comp.mus.example
2981 Retry rule: *.comp.mus.example F,2h,15m; F,4d,30m;
2982 .endd
2983 .new
2984 See chapter &<<CHAPretry>>& for a description of Exim's retry rules. The first
2985 argument, which is required, can be a complete address in the form
2986 &'local_part@domain'&, or it can be just a domain name. If the second argument
2987 contains a dot, it is interpreted as an optional second domain name; if no
2988 retry rule is found for the first argument, the second is tried. This ties in
2989 with Exim's behaviour when looking for retry rules for remote hosts &-- if no
2990 rule is found that matches the host, one that matches the mail domain is
2991 sought. Finally, an argument that is the name of a specific delivery error, as
2992 used in setting up retry rules, can be given. For example:
2993 .code
2994 exim -brt haydn.comp.mus.example quota_3d
2995 Retry rule: *@haydn.comp.mus.example quota_3d F,1h,15m
2996 .endd
2997 .wen
2999 .vitem &%-brw%&
3000 .oindex "&%-brw%&"
3001 .cindex "testing" "rewriting"
3002 .cindex "rewriting" "testing"
3003 This option is for testing address rewriting rules, and it must be followed by
3004 a single argument, consisting of either a local part without a domain, or a
3005 complete address with a fully qualified domain. Exim outputs how this address
3006 would be rewritten for each possible place it might appear. See chapter
3007 &<<CHAPrewrite>>& for further details.
3009 .vitem &%-bS%&
3010 .oindex "&%-bS%&"
3011 .cindex "SMTP" "batched incoming"
3012 .cindex "batched SMTP input"
3013 This option is used for batched SMTP input, which is an alternative interface
3014 for non-interactive local message submission. A number of messages can be
3015 submitted in a single run. However, despite its name, this is not really SMTP
3016 input. Exim reads each message's envelope from SMTP commands on the standard
3017 input, but generates no responses. If the caller is trusted, or
3018 &%untrusted_set_sender%& is set, the senders in the SMTP MAIL commands are
3019 believed; otherwise the sender is always the caller of Exim.
3021 The message itself is read from the standard input, in SMTP format (leading
3022 dots doubled), terminated by a line containing just a single dot. An error is
3023 provoked if the terminating dot is missing. A further message may then follow.
3025 As for other local message submissions, the contents of incoming batch SMTP
3026 messages can be checked using the non-SMTP ACL (see chapter &<<CHAPACL>>&).
3027 Unqualified addresses are automatically qualified using &%qualify_domain%& and
3028 &%qualify_recipient%&, as appropriate, unless the &%-bnq%& option is used.
3030 Some other SMTP commands are recognized in the input. HELO and EHLO act
3031 as RSET; VRFY, EXPN, ETRN, and HELP act as NOOP;
3032 QUIT quits, ignoring the rest of the standard input.
3034 .cindex "return code" "for &%-bS%&"
3035 If any error is encountered, reports are written to the standard output and
3036 error streams, and Exim gives up immediately. The return code is 0 if no error
3037 was detected; it is 1 if one or more messages were accepted before the error
3038 was detected; otherwise it is 2.
3040 More details of input using batched SMTP are given in section
3041 &<<SECTincomingbatchedSMTP>>&.
3043 .vitem &%-bs%&
3044 .oindex "&%-bs%&"
3045 .cindex "SMTP" "local input"
3046 .cindex "local SMTP input"
3047 This option causes Exim to accept one or more messages by reading SMTP commands
3048 on the standard input, and producing SMTP replies on the standard output. SMTP
3049 policy controls, as defined in ACLs (see chapter &<<CHAPACL>>&) are applied.
3050 Some user agents use this interface as a way of passing locally-generated
3051 messages to the MTA.
3053 In
3054 .cindex "sender" "source of"
3055 this usage, if the caller of Exim is trusted, or &%untrusted_set_sender%& is
3056 set, the senders of messages are taken from the SMTP MAIL commands.
3057 Otherwise the content of these commands is ignored and the sender is set up as
3058 the calling user. Unqualified addresses are automatically qualified using
3059 &%qualify_domain%& and &%qualify_recipient%&, as appropriate, unless the
3060 &%-bnq%& option is used.
3062 .cindex "inetd"
3063 The
3064 &%-bs%& option is also used to run Exim from &'inetd'&, as an alternative to
3065 using a listening daemon. Exim can distinguish the two cases by checking
3066 whether the standard input is a TCP/IP socket. When Exim is called from
3067 &'inetd'&, the source of the mail is assumed to be remote, and the comments
3068 above concerning senders and qualification do not apply. In this situation,
3069 Exim behaves in exactly the same way as it does when receiving a message via
3070 the listening daemon.
3072 .vitem &%-bt%&
3073 .oindex "&%-bt%&"
3074 .cindex "testing" "addresses"
3075 .cindex "address" "testing"
3076 This option runs Exim in address testing mode, in which each argument is taken
3077 as an address to be tested for deliverability. The results are written to the
3078 standard output. If a test fails, and the caller is not an admin user, no
3079 details of the failure are output, because these might contain sensitive
3080 information such as usernames and passwords for database lookups.
3082 If no arguments are given, Exim runs in an interactive manner, prompting with a
3083 right angle bracket for addresses to be tested.
3085 Unlike the &%-be%& test option, you cannot arrange for Exim to use the
3086 &[readline()]& function, because it is running as &'root'& and there are
3087 security issues.
3089 Each address is handled as if it were the recipient address of a message
3090 (compare the &%-bv%& option). It is passed to the routers and the result is
3091 written to the standard output. However, any router that has
3092 &%no_address_test%& set is bypassed. This can make &%-bt%& easier to use for
3093 genuine routing tests if your first router passes everything to a scanner
3094 program.
3096 The
3097 .cindex "return code" "for &%-bt%&"
3098 return code is 2 if any address failed outright; it is 1 if no address
3099 failed outright but at least one could not be resolved for some reason. Return
3100 code 0 is given only when all addresses succeed.
3102 &*Warning*&: &%-bt%& can only do relatively simple testing. If any of the
3103 routers in the configuration makes any tests on the sender address of a
3104 message,
3105 .cindex "&%-f%& option" "for address testing"
3106 you can use the &%-f%& option to set an appropriate sender when running
3107 &%-bt%& tests. Without it, the sender is assumed to be the calling user at the
3108 default qualifying domain. However, if you have set up (for example) routers
3109 whose behaviour depends on the contents of an incoming message, you cannot test
3110 those conditions using &%-bt%&. The &%-N%& option provides a possible way of
3111 doing such tests.
3113 .vitem &%-bV%&
3114 .oindex "&%-bV%&"
3115 .cindex "version number of Exim" "verifying"
3116 This option causes Exim to write the current version number, compilation
3117 number, and compilation date of the &'exim'& binary to the standard output.
3118 It also lists the DBM library this is being used, the optional modules (such as
3119 specific lookup types), the drivers that are included in the binary, and the
3120 name of the run time configuration file that is in use.
3122 As part of its operation, &%-bV%& causes Exim to read and syntax check its
3123 configuration file. However, this is a static check only. It cannot check
3124 values that are to be expanded. For example, although a misspelt ACL verb is
3125 detected, an error in the verb's arguments is not. You cannot rely on &%-bV%&
3126 alone to discover (for example) all the typos in the configuration; some
3127 realistic testing is needed. The &%-bh%& and &%-N%& options provide more
3128 dynamic testing facilities.
3130 .vitem &%-bv%&
3131 .oindex "&%-bv%&"
3132 .cindex "verifying address" "using &%-bv%&"
3133 .cindex "address" "verification"
3134 This option runs Exim in address verification mode, in which each argument is
3135 taken as an address to be verified. During normal operation, verification
3136 happens mostly as a consequence processing a &%verify%& condition in an ACL
3137 (see chapter &<<CHAPACL>>&). If you want to test an entire ACL, see the &%-bh%&
3138 option.
3140 If verification fails, and the caller is not an admin user, no details of the
3141 failure are output, because these might contain sensitive information such as
3142 usernames and passwords for database lookups.
3144 If no arguments are given, Exim runs in an interactive manner, prompting with a
3145 right angle bracket for addresses to be verified.
3147 Unlike the &%-be%& test option, you cannot arrange for Exim to use the
3148 &[readline()]& function, because it is running as &'exim'& and there are
3149 security issues.
3151 Verification differs from address testing (the &%-bt%& option) in that routers
3152 that have &%no_verify%& set are skipped, and if the address is accepted by a
3153 router that has &%fail_verify%& set, verification fails. The address is
3154 verified as a recipient if &%-bv%& is used; to test verification for a sender
3155 address, &%-bvs%& should be used.
3157 If the &%-v%& option is not set, the output consists of a single line for each
3158 address, stating whether it was verified or not, and giving a reason in the
3159 latter case. Otherwise, more details are given of how the address has been
3160 handled, and in the case of address redirection, all the generated addresses
3161 are also considered. Without &%-v%&, generating more than one address by
3162 redirection causes verification to end successfully.
3164 The
3165 .cindex "return code" "for &%-bv%&"
3166 return code is 2 if any address failed outright; it is 1 if no address
3167 failed outright but at least one could not be resolved for some reason. Return
3168 code 0 is given only when all addresses succeed.
3170 If any of the routers in the configuration makes any tests on the sender
3171 address of a message, you should use the &%-f%& option to set an appropriate
3172 sender when running &%-bv%& tests. Without it, the sender is assumed to be the
3173 calling user at the default qualifying domain.
3175 .vitem &%-bvs%&
3176 .oindex "&%-bvs%&"
3177 This option acts like &%-bv%&, but verifies the address as a sender rather
3178 than a recipient address. This affects any rewriting and qualification that
3179 might happen.
3181 .vitem &%-C%&&~<&'filelist'&>
3182 .oindex "&%-C%&"
3183 .cindex "configuration file" "alternate"
3184 .cindex "CONFIGURE_FILE"
3185 .cindex "alternate configuration file"
3186 This option causes Exim to find the run time configuration file from the given
3187 list instead of from the list specified by the CONFIGURE_FILE
3188 compile-time setting. Usually, the list will consist of just a single file
3189 name, but it can be a colon-separated list of names. In this case, the first
3190 file that exists is used. Failure to open an existing file stops Exim from
3191 proceeding any further along the list, and an error is generated.
3193 When this option is used by a caller other than root or the Exim user, and the
3194 list is different from the compiled-in list, Exim gives up its root privilege
3195 immediately, and runs with the real and effective uid and gid set to those of
3196 the caller. However, if ALT_CONFIG_ROOT_ONLY is defined in
3197 &_Local/Makefile_&, root privilege is retained for &%-C%& only if the caller of
3198 Exim is root.
3200 That is, the Exim user is no longer privileged in this regard. This build-time
3201 option is not set by default in the Exim source distribution tarbundle.
3202 However, if you are using a &"packaged"& version of Exim (source or binary),
3203 the packagers might have enabled it.
3205 Setting ALT_CONFIG_ROOT_ONLY locks out the possibility of testing a
3206 configuration using &%-C%& right through message reception and delivery, even
3207 if the caller is root. The reception works, but by that time, Exim is running
3208 as the Exim user, so when it re-executes to regain privilege for the delivery,
3209 the use of &%-C%& causes privilege to be lost. However, root can test reception
3210 and delivery using two separate commands (one to put a message on the queue,
3211 using &%-odq%&, and another to do the delivery, using &%-M%&).
3213 If ALT_CONFIG_PREFIX is defined &_in Local/Makefile_&, it specifies a
3214 prefix string with which any file named in a &%-C%& command line option
3215 must start. In addition, the file name must not contain the sequence &`/../`&.
3216 However, if the value of the &%-C%& option is identical to the value of
3217 CONFIGURE_FILE in &_Local/Makefile_&, Exim ignores &%-C%& and proceeds as
3218 usual. There is no default setting for ALT_CONFIG_PREFIX; when it is
3219 unset, any file name can be used with &%-C%&.
3221 ALT_CONFIG_PREFIX can be used to confine alternative configuration files
3222 to a directory to which only root has access. This prevents someone who has
3223 broken into the Exim account from running a privileged Exim with an arbitrary
3224 configuration file.
3226 The &%-C%& facility is useful for ensuring that configuration files are
3227 syntactically correct, but cannot be used for test deliveries, unless the
3228 caller is privileged, or unless it is an exotic configuration that does not
3229 require privilege. No check is made on the owner or group of the files
3230 specified by this option.
3232 .vitem &%-D%&<&'macro'&>=<&'value'&>
3233 .oindex "&%-D%&"
3234 .cindex "macro" "setting on command line"
3235 This option can be used to override macro definitions in the configuration file
3236 (see section &<<SECTmacrodefs>>&). However, like &%-C%&, if it is used by an
3237 unprivileged caller, it causes Exim to give up its root privilege.
3238 If DISABLE_D_OPTION is defined in &_Local/Makefile_&, the use of &%-D%& is
3239 completely disabled, and its use causes an immediate error exit.
3241 The entire option (including equals sign if present) must all be within one
3242 command line item. &%-D%& can be used to set the value of a macro to the empty
3243 string, in which case the equals sign is optional. These two commands are
3244 synonymous:
3245 .code
3246 exim -DABC ...
3247 exim -DABC= ...
3248 .endd
3249 To include spaces in a macro definition item, quotes must be used. If you use
3250 quotes, spaces are permitted around the macro name and the equals sign. For
3251 example:
3252 .code
3253 exim '-D ABC = something' ...
3254 .endd
3255 &%-D%& may be repeated up to 10 times on a command line.
3257 .vitem &%-d%&<&'debug&~options'&>
3258 .oindex "&%-d%&"
3259 .cindex "debugging" "list of selectors"
3260 .cindex "debugging" "&%-d%& option"
3261 This option causes debugging information to be written to the standard
3262 error stream. It is restricted to admin users because debugging output may show
3263 database queries that contain password information. Also, the details of users'
3264 filter files should be protected. When &%-d%& is used, &%-v%& is assumed. If
3265 &%-d%& is given on its own, a lot of standard debugging data is output. This
3266 can be reduced, or increased to include some more rarely needed information, by
3267 directly following &%-d%& with a string made up of names preceded by plus or
3268 minus characters. These add or remove sets of debugging data, respectively. For
3269 example, &%-d+filter%& adds filter debugging, whereas &%-d-all+filter%& selects
3270 only filter debugging. Note that no spaces are allowed in the debug setting.
3271 The available debugging categories are:
3272 .display
3273 &`acl `& ACL interpretation
3274 &`auth `& authenticators
3275 &`deliver `& general delivery logic
3276 &`dns `& DNS lookups (see also resolver)
3277 &`dnsbl `& DNS black list (aka RBL) code
3278 &`exec `& arguments for &[execv()]& calls
3279 &`expand `& detailed debugging for string expansions
3280 &`filter `& filter handling
3281 &`hints_lookup `& hints data lookups
3282 &`host_lookup `& all types of name-to-IP address handling
3283 &`ident `& ident lookup
3284 &`interface `& lists of local interfaces
3285 &`lists `& matching things in lists
3286 &`load `& system load checks
3287 &`local_scan `& can be used by &[local_scan()]& (see chapter &&&
3288 &<<CHAPlocalscan>>&)
3289 &`lookup `& general lookup code and all lookups
3290 &`memory `& memory handling
3291 &`pid `& add pid to debug output lines
3292 &`process_info `& setting info for the process log
3293 &`queue_run `& queue runs
3294 &`receive `& general message reception logic
3295 &`resolver `& turn on the DNS resolver's debugging output
3296 &`retry `& retry handling
3297 &`rewrite `& address rewriting
3298 &`route `& address routing
3299 &`timestamp `& add timestamp to debug output lines
3300 &`tls `& TLS logic
3301 &`transport `& transports
3302 &`uid `& changes of uid/gid and looking up uid/gid
3303 &`verify `& address verification logic
3304 &`all `& almost all of the above (see below), and also &%-v%&
3305 .endd
3306 The &`all`& option excludes &`memory`& when used as &`+all`&, but includes it
3307 for &`-all`&. The reason for this is that &`+all`& is something that people
3308 tend to use when generating debug output for Exim maintainers. If &`+memory`&
3309 is included, an awful lot of output that is very rarely of interest is
3310 generated, so it now has to be explicitly requested. However, &`-all`& does
3311 turn everything off.
3313 .cindex "resolver" "debugging output"
3314 .cindex "DNS resolver" "debugging output"
3315 The &`resolver`& option produces output only if the DNS resolver was compiled
3316 with DEBUG enabled. This is not the case in some operating systems. Also,
3317 unfortunately, debugging output from the DNS resolver is written to stdout
3318 rather than stderr.
3320 The default (&%-d%& with no argument) omits &`expand`&, &`filter`&,
3321 &`interface`&, &`load`&, &`memory`&, &`pid`&, &`resolver`&, and &`timestamp`&.
3322 However, the &`pid`& selector is forced when debugging is turned on for a
3323 daemon, which then passes it on to any re-executed Exims. Exim also
3324 automatically adds the pid to debug lines when several remote deliveries are
3325 run in parallel.
3327 The &`timestamp`& selector causes the current time to be inserted at the start
3328 of all debug output lines. This can be useful when trying to track down delays
3329 in processing.
3331 If the &%debug_print%& option is set in any driver, it produces output whenever
3332 any debugging is selected, or if &%-v%& is used.
3334 .vitem &%-dd%&<&'debug&~options'&>
3335 .oindex "&%-dd%&"
3336 This option behaves exactly like &%-d%& except when used on a command that
3337 starts a daemon process. In that case, debugging is turned off for the
3338 subprocesses that the daemon creates. Thus, it is useful for monitoring the
3339 behaviour of the daemon without creating as much output as full debugging does.
3341 .vitem &%-dropcr%&
3342 .oindex "&%-dropcr%&"
3343 This is an obsolete option that is now a no-op. It used to affect the way Exim
3344 handled CR and LF characters in incoming messages. What happens now is
3345 described in section &<<SECTlineendings>>&.
3347 .vitem &%-E%&
3348 .oindex "&%-E%&"
3349 .cindex "bounce message" "generating"
3350 This option specifies that an incoming message is a locally-generated delivery
3351 failure report. It is used internally by Exim when handling delivery failures
3352 and is not intended for external use. Its only effect is to stop Exim
3353 generating certain messages to the postmaster, as otherwise message cascades
3354 could occur in some situations. As part of the same option, a message id may
3355 follow the characters &%-E%&. If it does, the log entry for the receipt of the
3356 new message contains the id, following &"R="&, as a cross-reference.
3358 .vitem &%-e%&&'x'&
3359 .oindex "&%-e%&&'x'&"
3360 There are a number of Sendmail options starting with &%-oe%& which seem to be
3361 called by various programs without the leading &%o%& in the option. For
3362 example, the &%vacation%& program uses &%-eq%&. Exim treats all options of the
3363 form &%-e%&&'x'& as synonymous with the corresponding &%-oe%&&'x'& options.
3365 .vitem &%-F%&&~<&'string'&>
3366 .oindex "&%-F%&"
3367 .cindex "sender" "name"
3368 .cindex "name" "of sender"
3369 This option sets the sender's full name for use when a locally-generated
3370 message is being accepted. In the absence of this option, the user's &'gecos'&
3371 entry from the password data is used. As users are generally permitted to alter
3372 their &'gecos'& entries, no security considerations are involved. White space
3373 between &%-F%& and the <&'string'&> is optional.
3375 .vitem &%-f%&&~<&'address'&>
3376 .oindex "&%-f%&"
3377 .cindex "sender" "address"
3378 .cindex "address" "sender"
3379 .cindex "trusted user"
3380 .cindex "envelope sender"
3381 .cindex "user" "trusted"
3382 This option sets the address of the envelope sender of a locally-generated
3383 message (also known as the return path). The option can normally be used only
3384 by a trusted user, but &%untrusted_set_sender%& can be set to allow untrusted
3385 users to use it.
3387 Processes running as root or the Exim user are always trusted. Other
3388 trusted users are defined by the &%trusted_users%& or &%trusted_groups%&
3389 options. In the absence of &%-f%&, or if the caller is not trusted, the sender
3390 of a local message is set to the caller's login name at the default qualify
3391 domain.
3393 There is one exception to the restriction on the use of &%-f%&: an empty sender
3394 can be specified by any user, trusted or not, to create a message that can
3395 never provoke a bounce. An empty sender can be specified either as an empty
3396 string, or as a pair of angle brackets with nothing between them, as in these
3397 examples of shell commands:
3398 .code
3399 exim -f '<>' user@domain
3400 exim -f "" user@domain
3401 .endd
3402 In addition, the use of &%-f%& is not restricted when testing a filter file
3403 with &%-bf%& or when testing or verifying addresses using the &%-bt%& or
3404 &%-bv%& options.
3406 Allowing untrusted users to change the sender address does not of itself make
3407 it possible to send anonymous mail. Exim still checks that the &'From:'& header
3408 refers to the local user, and if it does not, it adds a &'Sender:'& header,
3409 though this can be overridden by setting &%no_local_from_check%&.
3411 White
3412 .cindex "&""From""& line"
3413 space between &%-f%& and the <&'address'&> is optional (that is, they can be
3414 given as two arguments or one combined argument). The sender of a
3415 locally-generated message can also be set (when permitted) by an initial
3416 &"From&~"& line in the message &-- see the description of &%-bm%& above &-- but
3417 if &%-f%& is also present, it overrides &"From&~"&.
3419 .vitem &%-G%&
3420 .oindex "&%-G%&"
3421 .cindex "Sendmail compatibility" "&%-G%& option ignored"
3422 This is a Sendmail option which is ignored by Exim.
3424 .vitem &%-h%&&~<&'number'&>
3425 .oindex "&%-h%&"
3426 .cindex "Sendmail compatibility" "&%-h%& option ignored"
3427 This option is accepted for compatibility with Sendmail, but has no effect. (In
3428 Sendmail it overrides the &"hop count"& obtained by counting &'Received:'&
3429 headers.)
3431 .vitem &%-i%&
3432 .oindex "&%-i%&"
3433 .cindex "Solaris" "&'mail'& command"
3434 .cindex "dot in incoming" "non-SMTP message"
3435 This option, which has the same effect as &%-oi%&, specifies that a dot on a
3436 line by itself should not terminate an incoming, non-SMTP message. I can find
3437 no documentation for this option in Solaris 2.4 Sendmail, but the &'mailx'&
3438 command in Solaris 2.4 uses it. See also &%-ti%&.
3440 .vitem &%-M%&&~<&'message&~id'&>&~<&'message&~id'&>&~...
3441 .oindex "&%-M%&"
3442 .cindex "forcing delivery"
3443 .cindex "delivery" "forcing attempt"
3444 .cindex "frozen messages" "forcing delivery"
3445 This option requests Exim to run a delivery attempt on each message in turn. If
3446 any of the messages are frozen, they are automatically thawed before the
3447 delivery attempt. The settings of &%queue_domains%&, &%queue_smtp_domains%&,
3448 and &%hold_domains%& are ignored.
3450 Retry
3451 .cindex "hints database" "overriding retry hints"
3452 hints for any of the addresses are overridden &-- Exim tries to deliver even if
3453 the normal retry time has not yet been reached. This option requires the caller
3454 to be an admin user. However, there is an option called &%prod_requires_admin%&
3455 which can be set false to relax this restriction (and also the same requirement
3456 for the &%-q%&, &%-R%&, and &%-S%& options).
3458 The deliveries happen synchronously, that is, the original Exim process does
3459 not terminate until all the delivery attempts have finished. No output is
3460 produced unless there is a serious error. If you want to see what is happening,
3461 use the &%-v%& option as well, or inspect Exim's main log.
3463 .vitem &%-Mar%&&~<&'message&~id'&>&~<&'address'&>&~<&'address'&>&~...
3464 .oindex "&%-Mar%&"
3465 .cindex "message" "adding recipients"
3466 .cindex "recipient" "adding"
3467 This option requests Exim to add the addresses to the list of recipients of the
3468 message (&"ar"& for &"add recipients"&). The first argument must be a message
3469 id, and the remaining ones must be email addresses. However, if the message is
3470 active (in the middle of a delivery attempt), it is not altered. This option
3471 can be used only by an admin user.
3473 .vitem "&%-MC%&&~<&'transport'&>&~<&'hostname'&>&~<&'sequence&~number'&>&&&
3474 &~<&'message&~id'&>"
3475 .oindex "&%-MC%&"
3476 .cindex "SMTP" "passed connection"
3477 .cindex "SMTP" "multiple deliveries"
3478 .cindex "multiple SMTP deliveries"
3479 This option is not intended for use by external callers. It is used internally
3480 by Exim to invoke another instance of itself to deliver a waiting message using
3481 an existing SMTP connection, which is passed as the standard input. Details are
3482 given in chapter &<<CHAPSMTP>>&. This must be the final option, and the caller
3483 must be root or the Exim user in order to use it.
3485 .vitem &%-MCA%&
3486 .oindex "&%-MCA%&"
3487 This option is not intended for use by external callers. It is used internally
3488 by Exim in conjunction with the &%-MC%& option. It signifies that the
3489 connection to the remote host has been authenticated.
3491 .vitem &%-MCP%&
3492 .oindex "&%-MCP%&"
3493 This option is not intended for use by external callers. It is used internally
3494 by Exim in conjunction with the &%-MC%& option. It signifies that the server to
3495 which Exim is connected supports pipelining.
3497 .vitem &%-MCQ%&&~<&'process&~id'&>&~<&'pipe&~fd'&>
3498 .oindex "&%-MCQ%&"
3499 This option is not intended for use by external callers. It is used internally
3500 by Exim in conjunction with the &%-MC%& option when the original delivery was
3501 started by a queue runner. It passes on the process id of the queue runner,
3502 together with the file descriptor number of an open pipe. Closure of the pipe
3503 signals the final completion of the sequence of processes that are passing
3504 messages through the same SMTP connection.
3506 .vitem &%-MCS%&
3507 .oindex "&%-MCS%&"
3508 This option is not intended for use by external callers. It is used internally
3509 by Exim in conjunction with the &%-MC%& option, and passes on the fact that the
3510 SMTP SIZE option should be used on messages delivered down the existing
3511 connection.
3513 .vitem &%-MCT%&
3514 .oindex "&%-MCT%&"
3515 This option is not intended for use by external callers. It is used internally
3516 by Exim in conjunction with the &%-MC%& option, and passes on the fact that the
3517 host to which Exim is connected supports TLS encryption.
3519 .vitem &%-Mc%&&~<&'message&~id'&>&~<&'message&~id'&>&~...
3520 .oindex "&%-Mc%&"
3521 .cindex "hints database" "not overridden by &%-Mc%&"
3522 .cindex "delivery" "manually started &-- not forced"
3523 This option requests Exim to run a delivery attempt on each message in turn,
3524 but unlike the &%-M%& option, it does check for retry hints, and respects any
3525 that are found. This option is not very useful to external callers. It is
3526 provided mainly for internal use by Exim when it needs to re-invoke itself in
3527 order to regain root privilege for a delivery (see chapter &<<CHAPsecurity>>&).
3528 However, &%-Mc%& can be useful when testing, in order to run a delivery that
3529 respects retry times and other options such as &%hold_domains%& that are
3530 overridden when &%-M%& is used. Such a delivery does not count as a queue run.
3531 If you want to run a specific delivery as if in a queue run, you should use
3532 &%-q%& with a message id argument. A distinction between queue run deliveries
3533 and other deliveries is made in one or two places.
3535 .vitem &%-Mes%&&~<&'message&~id'&>&~<&'address'&>
3536 .oindex "&%-Mes%&"
3537 .cindex "message" "changing sender"
3538 .cindex "sender" "changing"
3539 This option requests Exim to change the sender address in the message to the
3540 given address, which must be a fully qualified address or &"<>"& (&"es"& for
3541 &"edit sender"&). There must be exactly two arguments. The first argument must
3542 be a message id, and the second one an email address. However, if the message
3543 is active (in the middle of a delivery attempt), its status is not altered.
3544 This option can be used only by an admin user.
3546 .vitem &%-Mf%&&~<&'message&~id'&>&~<&'message&~id'&>&~...
3547 .oindex "&%-Mf%&"
3548 .cindex "freezing messages"
3549 .cindex "message" "manually freezing"
3550 This option requests Exim to mark each listed message as &"frozen"&. This
3551 prevents any delivery attempts taking place until the message is &"thawed"&,
3552 either manually or as a result of the &%auto_thaw%& configuration option.
3553 However, if any of the messages are active (in the middle of a delivery
3554 attempt), their status is not altered. This option can be used only by an admin
3555 user.
3557 .vitem &%-Mg%&&~<&'message&~id'&>&~<&'message&~id'&>&~...
3558 .oindex "&%-Mg%&"
3559 .cindex "giving up on messages"
3560 .cindex "message" "abandoning delivery attempts"
3561 .cindex "delivery" "abandoning further attempts"
3562 This option requests Exim to give up trying to deliver the listed messages,
3563 including any that are frozen. However, if any of the messages are active,
3564 their status is not altered. For non-bounce messages, a delivery error message
3565 is sent to the sender, containing the text &"cancelled by administrator"&.
3566 Bounce messages are just discarded. This option can be used only by an admin
3567 user.
3569 .vitem &%-Mmad%&&~<&'message&~id'&>&~<&'message&~id'&>&~...
3570 .oindex "&%-Mmad%&"
3571 .cindex "delivery" "cancelling all"
3572 This option requests Exim to mark all the recipient addresses in the messages
3573 as already delivered (&"mad"& for &"mark all delivered"&). However, if any
3574 message is active (in the middle of a delivery attempt), its status is not
3575 altered. This option can be used only by an admin user.
3577 .vitem &%-Mmd%&&~<&'message&~id'&>&~<&'address'&>&~<&'address'&>&~...
3578 .oindex "&%-Mmd%&"
3579 .cindex "delivery" "cancelling by address"
3580 .cindex "recipient" "removing"
3581 .cindex "removing recipients"
3582 This option requests Exim to mark the given addresses as already delivered
3583 (&"md"& for &"mark delivered"&). The first argument must be a message id, and
3584 the remaining ones must be email addresses. These are matched to recipient
3585 addresses in the message in a case-sensitive manner. If the message is active
3586 (in the middle of a delivery attempt), its status is not altered. This option
3587 can be used only by an admin user.
3589 .vitem &%-Mrm%&&~<&'message&~id'&>&~<&'message&~id'&>&~...
3590 .oindex "&%-Mrm%&"
3591 .cindex "removing messages"
3592 .cindex "abandoning mail"
3593 .cindex "message" "manually discarding"
3594 This option requests Exim to remove the given messages from the queue. No
3595 bounce messages are sent; each message is simply forgotten. However, if any of
3596 the messages are active, their status is not altered. This option can be used
3597 only by an admin user or by the user who originally caused the message to be
3598 placed on the queue.
3600 .vitem &%-Mt%&&~<&'message&~id'&>&~<&'message&~id'&>&~...
3601 .oindex "&%-Mt%&"
3602 .cindex "thawing messages"
3603 .cindex "unfreezing messages"
3604 .cindex "frozen messages" "thawing"
3605 .cindex "message" "thawing frozen"
3606 This option requests Exim to &"thaw"& any of the listed messages that are
3607 &"frozen"&, so that delivery attempts can resume. However, if any of the
3608 messages are active, their status is not altered. This option can be used only
3609 by an admin user.
3611 .vitem &%-Mvb%&&~<&'message&~id'&>
3612 .oindex "&%-Mvb%&"
3613 .cindex "listing" "message body"
3614 .cindex "message" "listing body of"
3615 This option causes the contents of the message body (-D) spool file to be
3616 written to the standard output. This option can be used only by an admin user.
3618 .vitem &%-Mvh%&&~<&'message&~id'&>
3619 .oindex "&%-Mvh%&"
3620 .cindex "listing" "message headers"
3621 .cindex "header lines" "listing"
3622 .cindex "message" "listing header lines"
3623 This option causes the contents of the message headers (-H) spool file to be
3624 written to the standard output. This option can be used only by an admin user.
3626 .vitem &%-Mvl%&&~<&'message&~id'&>
3627 .oindex "&%-Mvl%&"
3628 .cindex "listing" "message log"
3629 .cindex "message" "listing message log"
3630 This option causes the contents of the message log spool file to be written to
3631 the standard output. This option can be used only by an admin user.
3633 .vitem &%-m%&
3634 .oindex "&%-m%&"
3635 This is apparently a synonym for &%-om%& that is accepted by Sendmail, so Exim
3636 treats it that way too.
3638 .vitem &%-N%&
3639 .oindex "&%-N%&"
3640 .cindex "debugging" "&%-N%& option"
3641 .cindex "debugging" "suppressing delivery"
3642 This is a debugging option that inhibits delivery of a message at the transport
3643 level. It implies &%-v%&. Exim goes through many of the motions of delivery &--
3644 it just doesn't actually transport the message, but instead behaves as if it
3645 had successfully done so. However, it does not make any updates to the retry
3646 database, and the log entries for deliveries are flagged with &"*>"& rather
3647 than &"=>"&.
3649 Because &%-N%& discards any message to which it applies, only root or the Exim
3650 user are allowed to use it with &%-bd%&, &%-q%&, &%-R%& or &%-M%&. In other
3651 words, an ordinary user can use it only when supplying an incoming message to
3652 which it will apply. Although transportation never fails when &%-N%& is set, an
3653 address may be deferred because of a configuration problem on a transport, or a
3654 routing problem. Once &%-N%& has been used for a delivery attempt, it sticks to
3655 the message, and applies to any subsequent delivery attempts that may happen
3656 for that message.
3658 .vitem &%-n%&
3659 .oindex "&%-n%&"
3660 .cindex "Sendmail compatibility" "&%-n%& option ignored"
3661 This option is interpreted by Sendmail to mean &"no aliasing"&. It is ignored
3662 by Exim.
3664 .vitem &%-O%&&~<&'data'&>
3665 .oindex "&%-O%&"
3666 This option is interpreted by Sendmail to mean &`set option`&. It is ignored by
3667 Exim.
3669 .vitem &%-oA%&&~<&'file&~name'&>
3670 .oindex "&%-oA%&"
3671 .cindex "Sendmail compatibility" "&%-oA%& option"
3672 This option is used by Sendmail in conjunction with &%-bi%& to specify an
3673 alternative alias file name. Exim handles &%-bi%& differently; see the
3674 description above.
3676 .vitem &%-oB%&&~<&'n'&>
3677 .oindex "&%-oB%&"
3678 .cindex "SMTP" "passed connection"
3679 .cindex "SMTP" "multiple deliveries"
3680 .cindex "multiple SMTP deliveries"
3681 This is a debugging option which limits the maximum number of messages that can
3682 be delivered down one SMTP connection, overriding the value set in any &(smtp)&
3683 transport. If <&'n'&> is omitted, the limit is set to 1.
3685 .vitem &%-odb%&
3686 .oindex "&%-odb%&"
3687 .cindex "background delivery"
3688 .cindex "delivery" "in the background"
3689 This option applies to all modes in which Exim accepts incoming messages,
3690 including the listening daemon. It requests &"background"& delivery of such
3691 messages, which means that the accepting process automatically starts a
3692 delivery process for each message received, but does not wait for the delivery
3693 processes to finish.
3695 When all the messages have been received, the reception process exits,
3696 leaving the delivery processes to finish in their own time. The standard output
3697 and error streams are closed at the start of each delivery process.
3698 This is the default action if none of the &%-od%& options are present.
3700 If one of the queueing options in the configuration file
3701 (&%queue_only%& or &%queue_only_file%&, for example) is in effect, &%-odb%&
3702 overrides it if &%queue_only_override%& is set true, which is the default
3703 setting. If &%queue_only_override%& is set false, &%-odb%& has no effect.
3705 .vitem &%-odf%&
3706 .oindex "&%-odf%&"
3707 .cindex "foreground delivery"
3708 .cindex "delivery" "in the foreground"
3709 This option requests &"foreground"& (synchronous) delivery when Exim has
3710 accepted a locally-generated message. (For the daemon it is exactly the same as
3711 &%-odb%&.) A delivery process is automatically started to deliver the message,
3712 and Exim waits for it to complete before proceeding.
3714 The original Exim reception process does not finish until the delivery
3715 process for the final message has ended. The standard error stream is left open
3716 during deliveries.
3718 However, like &%-odb%&, this option has no effect if &%queue_only_override%& is
3719 false and one of the queueing options in the configuration file is in effect.
3721 If there is a temporary delivery error during foreground delivery, the
3722 message is left on the queue for later delivery, and the original reception
3723 process exits. See chapter &<<CHAPnonqueueing>>& for a way of setting up a
3724 restricted configuration that never queues messages.
3727 .vitem &%-odi%&
3728 .oindex "&%-odi%&"
3729 This option is synonymous with &%-odf%&. It is provided for compatibility with
3730 Sendmail.
3732 .vitem &%-odq%&
3733 .oindex "&%-odq%&"
3734 .cindex "non-immediate delivery"
3735 .cindex "delivery" "suppressing immediate"
3736 .cindex "queueing incoming messages"
3737 This option applies to all modes in which Exim accepts incoming messages,
3738 including the listening daemon. It specifies that the accepting process should
3739 not automatically start a delivery process for each message received. Messages
3740 are placed on the queue, and remain there until a subsequent queue runner
3741 process encounters them. There are several configuration options (such as
3742 &%queue_only%&) that can be used to queue incoming messages under certain
3743 conditions. This option overrides all of them and also &%-odqs%&. It always
3744 forces queueing.
3746 .vitem &%-odqs%&
3747 .oindex "&%-odqs%&"
3748 .cindex "SMTP" "delaying delivery"
3749 This option is a hybrid between &%-odb%&/&%-odi%& and &%-odq%&.
3750 However, like &%-odb%& and &%-odi%&, this option has no effect if
3751 &%queue_only_override%& is false and one of the queueing options in the
3752 configuration file is in effect.
3754 When &%-odqs%& does operate, a delivery process is started for each incoming
3755 message, in the background by default, but in the foreground if &%-odi%& is
3756 also present. The recipient addresses are routed, and local deliveries are done
3757 in the normal way. However, if any SMTP deliveries are required, they are not
3758 done at this time, so the message remains on the queue until a subsequent queue
3759 runner process encounters it. Because routing was done, Exim knows which
3760 messages are waiting for which hosts, and so a number of messages for the same
3761 host can be sent in a single SMTP connection. The &%queue_smtp_domains%&
3762 configuration option has the same effect for specific domains. See also the
3763 &%-qq%& option.
3765 .vitem &%-oee%&
3766 .oindex "&%-oee%&"
3767 .cindex "error" "reporting"
3768 If an error is detected while a non-SMTP message is being received (for
3769 example, a malformed address), the error is reported to the sender in a mail
3770 message.
3772 .cindex "return code" "for &%-oee%&"
3773 Provided
3774 this error message is successfully sent, the Exim receiving process
3775 exits with a return code of zero. If not, the return code is 2 if the problem
3776 is that the original message has no recipients, or 1 any other error. This is
3777 the default &%-oe%&&'x'& option if Exim is called as &'rmail'&.
3779 .vitem &%-oem%&
3780 .oindex "&%-oem%&"
3781 .cindex "error" "reporting"
3782 .cindex "return code" "for &%-oem%&"
3783 This is the same as &%-oee%&, except that Exim always exits with a non-zero
3784 return code, whether or not the error message was successfully sent.
3785 This is the default &%-oe%&&'x'& option, unless Exim is called as &'rmail'&.
3787 .vitem &%-oep%&
3788 .oindex "&%-oep%&"
3789 .cindex "error" "reporting"
3790 If an error is detected while a non-SMTP message is being received, the
3791 error is reported by writing a message to the standard error file (stderr).
3792 .cindex "return code" "for &%-oep%&"
3793 The return code is 1 for all errors.
3795 .vitem &%-oeq%&
3796 .oindex "&%-oeq%&"
3797 .cindex "error" "reporting"
3798 This option is supported for compatibility with Sendmail, but has the same
3799 effect as &%-oep%&.
3801 .vitem &%-oew%&
3802 .oindex "&%-oew%&"
3803 .cindex "error" "reporting"
3804 This option is supported for compatibility with Sendmail, but has the same
3805 effect as &%-oem%&.
3807 .vitem &%-oi%&
3808 .oindex "&%-oi%&"
3809 .cindex "dot in incoming" "non-SMTP message"
3810 This option, which has the same effect as &%-i%&, specifies that a dot on a
3811 line by itself should not terminate an incoming, non-SMTP message. Otherwise, a
3812 single dot does terminate, though Exim does no special processing for other
3813 lines that start with a dot. This option is set by default if Exim is called as
3814 &'rmail'&. See also &%-ti%&.
3816 .vitem &%-oitrue%&
3817 .oindex "&%-oitrue%&"
3818 This option is treated as synonymous with &%-oi%&.
3820 .vitem &%-oMa%&&~<&'host&~address'&>
3821 .oindex "&%-oMa%&"
3822 .cindex "sender host address" "specifying for local message"
3823 A number of options starting with &%-oM%& can be used to set values associated
3824 with remote hosts on locally-submitted messages (that is, messages not received
3825 over TCP/IP). These options can be used by any caller in conjunction with the
3826 &%-bh%&, &%-be%&, &%-bf%&, &%-bF%&, &%-bt%&, or &%-bv%& testing options. In
3827 other circumstances, they are ignored unless the caller is trusted.
3829 The &%-oMa%& option sets the sender host address. This may include a port
3830 number at the end, after a full stop (period). For example:
3831 .code
3832 exim -bs -oMa
3833 .endd
3834 An alternative syntax is to enclose the IP address in square brackets,
3835 followed by a colon and the port number:
3836 .code
3837 exim -bs -oMa []:1234
3838 .endd
3839 The IP address is placed in the &$sender_host_address$& variable, and the
3840 port, if present, in &$sender_host_port$&.
3842 .vitem &%-oMaa%&&~<&'name'&>
3843 .oindex "&%-oMaa%&"
3844 .cindex "authentication name" "specifying for local message"
3845 See &%-oMa%& above for general remarks about the &%-oM%& options. The &%-oMaa%&
3846 option sets the value of &$sender_host_authenticated$& (the authenticator
3847 name). See chapter &<<CHAPSMTPAUTH>>& for a discussion of SMTP authentication.
3849 .vitem &%-oMai%&&~<&'string'&>
3850 .oindex "&%-oMai%&"
3851 .cindex "authentication id" "specifying for local message"
3852 See &%-oMa%& above for general remarks about the &%-oM%& options. The &%-oMai%&
3853 option sets the value of &$authenticated_id$& (the id that was authenticated).
3854 This overrides the default value (the caller's login id) for messages from
3855 local sources. See chapter &<<CHAPSMTPAUTH>>& for a discussion of authenticated
3856 ids.
3858 .vitem &%-oMas%&&~<&'address'&>
3859 .oindex "&%-oMas%&"
3860 .cindex "authentication sender" "specifying for local message"
3861 See &%-oMa%& above for general remarks about the &%-oM%& options. The &%-oMas%&
3862 option sets the authenticated sender value in &$authenticated_sender$&. It
3863 overrides the sender address that is created from the caller's login id for
3864 messages from local sources. See chapter &<<CHAPSMTPAUTH>>& for a discussion of
3865 authenticated senders.
3867 .vitem &%-oMi%&&~<&'interface&~address'&>
3868 .oindex "&%-oMi%&"
3869 .cindex "interface address" "specifying for local message"
3870 See &%-oMa%& above for general remarks about the &%-oM%& options. The &%-oMi%&
3871 option sets the IP interface address value. A port number may be included,
3872 using the same syntax as for &%-oMa%&. The interface address is placed in
3873 &$interface_address$& and the port number, if present, in &$interface_port$&.
3875 .vitem &%-oMr%&&~<&'protocol&~name'&>
3876 .oindex "&%-oMr%&"
3877 .cindex "protocol" "incoming &-- specifying for local message"
3878 .cindex "&$received_protocol$&"
3879 See &%-oMa%& above for general remarks about the &%-oM%& options. The &%-oMr%&
3880 option sets the received protocol value that is stored in
3881 &$received_protocol$&. However, this applies only when &%-bs%& is not used. For
3882 interactive SMTP input (&%-bs%&), the protocol is always &"local-"& followed by
3883 one of the standard SMTP protocol names (see the description of
3884 &$received_protocol$& in section &<<SECTexpvar>>&). For &%-bS%& (batch SMTP)
3885 however, the protocol can be set by &%-oMr%&.
3887 .vitem &%-oMs%&&~<&'host&~name'&>
3888 .oindex "&%-oMs%&"
3889 .cindex "sender host name" "specifying for local message"
3890 See &%-oMa%& above for general remarks about the &%-oM%& options. The &%-oMs%&
3891 option sets the sender host name in &$sender_host_name$&. When this option is
3892 present, Exim does not attempt to look up a host name from an IP address; it
3893 uses the name it is given.
3895 .vitem &%-oMt%&&~<&'ident&~string'&>
3896 .oindex "&%-oMt%&"
3897 .cindex "sender ident string" "specifying for local message"
3898 See &%-oMa%& above for general remarks about the &%-oM%& options. The &%-oMt%&
3899 option sets the sender ident value in &$sender_ident$&. The default setting for
3900 local callers is the login id of the calling process.
3902 .vitem &%-om%&
3903 .oindex "&%-om%&"
3904 .cindex "Sendmail compatibility" "&%-om%& option ignored"
3905 In Sendmail, this option means &"me too"&, indicating that the sender of a
3906 message should receive a copy of the message if the sender appears in an alias
3907 expansion. Exim always does this, so the option does nothing.
3909 .vitem &%-oo%&
3910 .oindex "&%-oo%&"
3911 .cindex "Sendmail compatibility" "&%-oo%& option ignored"
3912 This option is ignored. In Sendmail it specifies &"old style headers"&,
3913 whatever that means.
3915 .vitem &%-oP%&&~<&'path'&>
3916 .oindex "&%-oP%&"
3917 .cindex "pid (process id)" "of daemon"
3918 .cindex "daemon" "process id (pid)"
3919 This option is useful only in conjunction with &%-bd%& or &%-q%& with a time
3920 value. The option specifies the file to which the process id of the daemon is
3921 written. When &%-oX%& is used with &%-bd%&, or when &%-q%& with a time is used
3922 without &%-bd%&, this is the only way of causing Exim to write a pid file,
3923 because in those cases, the normal pid file is not used.
3925 .vitem &%-or%&&~<&'time'&>
3926 .oindex "&%-or%&"
3927 .cindex "timeout" "for non-SMTP input"
3928 This option sets a timeout value for incoming non-SMTP messages. If it is not
3929 set, Exim will wait forever for the standard input. The value can also be set
3930 by the &%receive_timeout%& option. The format used for specifying times is
3931 described in section &<<SECTtimeformat>>&.
3933 .vitem &%-os%&&~<&'time'&>
3934 .oindex "&%-os%&"
3935 .cindex "timeout" "for SMTP input"
3936 .cindex "SMTP timeout" "input"
3937 This option sets a timeout value for incoming SMTP messages. The timeout
3938 applies to each SMTP command and block of data. The value can also be set by
3939 the &%smtp_receive_timeout%& option; it defaults to 5 minutes. The format used
3940 for specifying times is described in section &<<SECTtimeformat>>&.
3942 .vitem &%-ov%&
3943 .oindex "&%-ov%&"
3944 This option has exactly the same effect as &%-v%&.
3946 .vitem &%-oX%&&~<&'number&~or&~string'&>
3947 .oindex "&%-oX%&"
3948 .cindex "TCP/IP" "setting listening ports"
3949 .cindex "TCP/IP" "setting listening interfaces"
3950 .cindex "port" "receiving TCP/IP"
3951 This option is relevant only when the &%-bd%& (start listening daemon) option
3952 is also given. It controls which ports and interfaces the daemon uses. Details
3953 of the syntax, and how it interacts with configuration file options, are given
3954 in chapter &<<CHAPinterfaces>>&. When &%-oX%& is used to start a daemon, no pid
3955 file is written unless &%-oP%& is also present to specify a pid file name.
3957 .vitem &%-pd%&
3958 .oindex "&%-pd%&"
3959 .cindex "Perl" "starting the interpreter"
3960 This option applies when an embedded Perl interpreter is linked with Exim (see
3961 chapter &<<CHAPperl>>&). It overrides the setting of the &%perl_at_start%&
3962 option, forcing the starting of the interpreter to be delayed until it is
3963 needed.
3965 .vitem &%-ps%&
3966 .oindex "&%-ps%&"
3967 .cindex "Perl" "starting the interpreter"
3968 This option applies when an embedded Perl interpreter is linked with Exim (see
3969 chapter &<<CHAPperl>>&). It overrides the setting of the &%perl_at_start%&
3970 option, forcing the starting of the interpreter to occur as soon as Exim is
3971 started.
3973 .vitem &%-p%&<&'rval'&>:<&'sval'&>
3974 .oindex "&%-p%&"
3975 For compatibility with Sendmail, this option is equivalent to
3976 .display
3977 &`-oMr`& <&'rval'&> &`-oMs`& <&'sval'&>
3978 .endd
3979 It sets the incoming protocol and host name (for trusted callers). The
3980 host name and its colon can be omitted when only the protocol is to be set.
3981 Note the Exim already has two private options, &%-pd%& and &%-ps%&, that refer
3982 to embedded Perl. It is therefore impossible to set a protocol value of &`p`&
3983 or &`s`& using this option (but that does not seem a real limitation).
3985 .vitem &%-q%&
3986 .oindex "&%-q%&"
3987 .cindex "queue runner" "starting manually"
3988 This option is normally restricted to admin users. However, there is a
3989 configuration option called &%prod_requires_admin%& which can be set false to
3990 relax this restriction (and also the same requirement for the &%-M%&, &%-R%&,
3991 and &%-S%& options).
3993 .cindex "queue runner" "description of operation"
3994 The &%-q%& option starts one queue runner process. This scans the queue of
3995 waiting messages, and runs a delivery process for each one in turn. It waits