1 This document contains detailed information about incompatibilities that might
2 be encountered when upgrading from one release of Exim to another. The
3 information is in reverse order of release numbers. Mostly these are relatively
4 small points, and the configuration file is normally upwards compatible, but
5 there have been two big upheavals...
8 **************************************************************************
9 * There was a big reworking of the way mail routing works for release *
10 * 4.00. Previously used "directors" were abolished, and all routing is *
11 * now done by routers. Policy controls for incoming mail are now done by *
12 * Access Control Lists instead of separate options. All this means that *
13 * pre-4.00 configuration files have to be massively converted. If you *
14 * are coming from a 3.xx release, please read the document in the file *
15 * doc/Exim4.upgrade, and allow some time to complete the upgrade. *
17 * There was a big reworking of the way domain/host/net/address lists are *
18 * handled at release 3.00. If you are coming from a pre-3.00 release, it *
19 * might be easier to start again from a default configuration. Otherwise *
20 * you need to read doc/Exim3.upgrade and do a double conversion of your *
21 * configuration file. *
22 **************************************************************************
25 The rest of this document contains information about changes in 4.xx releases
26 that might affect a running system.
32 * BEWARE backwards-incompatible changes in SSL libraries, thus the version
33 bump. See points below for details.
35 * The value of $tls_peerdn is now print-escaped when written to the spool file
36 in a -tls_peerdn line, and unescaped when read back in. We received reports
37 of values with embedded newlines, which caused spool file corruption.
39 If you have a corrupt spool file and you wish to recover the contents after
40 upgrading, then lock the message, replace the new-lines that should be part
41 of the -tls_peerdn line with the two-character sequence \n and then unlock
42 the message. No tool has been provided as we believe this is a rare
45 * With OpenSSL 1.0.1+, Exim now supports TLS 1.1 and TLS 1.2. If built
46 against 1.0.1a then you will get a warning message and the
47 "openssl_options" value will not parse "no_tlsv1_1": the value changes
48 incompatibly between 1.0.1a and 1.0.1b, because the value chosen for 1.0.1a
49 is infelicitous. We advise avoiding 1.0.1a.
51 "openssl_options" gains "no_tlsv1_1", "no_tlsv1_2" and "no_compression".
53 COMPATIBILITY WARNING: The default value of "openssl_options" is no longer
54 "+dont_insert_empty_fragments". We default to unset. That old default was
55 grandfathered in from before openssl_options became a configuration option.
56 Empty fragments are inserted by default through TLS1.0, to partially defend
57 against certain attacks; TLS1.1+ change the protocol so that this is not
58 needed. The DIEF SSL option was required for some old releases of mail
59 clients which did not gracefully handle the empty fragments, and was
60 initially set in Exim release 4.31 (see ChangeLog, item 37).
62 If you still have affected mail-clients, and you see SSL protocol failures
63 with this release of Exim, set:
64 openssl_options = +dont_insert_empty_fragments
65 in the main section of your Exim configuration file. You're trading off
66 security for compatibility. Exim is now defaulting to higher security and
67 rewarding more modern clients.
69 If the option tls_dhparams is set and the parameters loaded from the file
70 have a bit-count greater than the new option tls_dh_max_bits, then the file
71 will now be ignored. If this affects you, raise the tls_dh_max_bits limit.
72 We suspect that most folks are using dated defaults and will not be affected.
74 * Ldap lookups returning multi-valued attributes now separate the attributes
75 with only a comma, not a comma-space sequence. Also, an actual comma within
76 a returned attribute is doubled. This makes it possible to parse the
77 attribute as a comma-separated list. Note the distinction from multiple
78 attributes being returned, where each one is a name=value pair.
80 * accept_8bitmime now defaults on, which is not RFC compliant but is better
81 suited to today's Internet. See http://cr.yp.to/smtp/8bitmime.html for a
82 sane rationale. Those who wish to be strictly RFC compliant, or know that
83 they need to talk to servers that are not 8-bit-clean, now need to take
84 explicit configuration action to default this option off. This is not a
85 new option, you can safely force it off before upgrading, to decouple
86 configuration changes from the binary upgrade while remaining RFC compliant.
88 * The GnuTLS support has been mostly rewritten, to use APIs which don't cause
89 deprecation warnings in GnuTLS 2.12.x. As part of this, these three options
90 are no longer supported:
94 gnutls_require_protocols
96 Their functionality is entirely subsumed into tls_require_ciphers. In turn,
97 tls_require_ciphers is no longer an Exim list and is not parsed by Exim, but
98 is instead given to gnutls_priority_init(3), which expects a priority string;
99 this behaviour is much closer to the OpenSSL behaviour. See:
101 http://www.gnu.org/software/gnutls/manual/html_node/Priority-Strings.html
103 for fuller documentation of the strings parsed. The three gnutls_require_*
104 options are still parsed by Exim and, for this release, silently ignored.
105 A future release will add warnings, before a later still release removes
106 parsing entirely and the presence of the options will be a configuration
109 Note that by default, GnuTLS will not accept RSA-MD5 signatures in chains.
110 A tls_require_ciphers value of NORMAL:%VERIFY_ALLOW_SIGN_RSA_MD5 may
111 re-enable support, but this is not supported by the Exim maintainers.
112 Our test suite no longer includes MD5-based certificates.
114 This rewrite means that Exim will continue to build against GnuTLS in the
115 future, brings Exim closer to other GnuTLS applications and lets us add
116 support for SNI and other features more readily. We regret that it wasn't
117 feasible to retain the three dropped options.
119 * If built with TLS support, then Exim will now validate the value of
120 the main section tls_require_ciphers option at start-up. Before, this
121 would cause a STARTTLS 4xx failure, now it causes a failure to start.
122 Running with a broken configuration which causes failures that may only
123 be left in the logs has been traded off for something more visible. This
124 change makes an existing problem more prominent, but we do not believe
125 anyone would deliberately be running with an invalid tls_require_ciphers
128 This also means that library linkage issues caused by conflicts of some
129 kind might take out the main daemon, not just the delivery or receiving
130 process. Conceivably some folks might prefer to continue delivering
131 mail plaintext when their binary is broken in this way, if there is a
132 server that is a candidate to receive such mails that does not advertise
133 STARTTLS. Note that Exim is typically a setuid root binary and given
134 broken linkage problems that cause segfaults, we feel it is safer to
135 fail completely. (The check is not done as root, to ensure that problems
136 here are not made worse by the check).
142 * GnuTLS will now attempt to use TLS 1.2 and TLS 1.1 before TLS 1.0 and SSL3,
143 if supported by your GnuTLS library. Use the existing
144 "gnutls_require_protocols" option to downgrade this if that will be a
145 problem. Prior to this release, supported values were "TLS1" and "SSL3",
146 so you should be able to update configuration prior to update.
148 [nb: gnutls_require_protocols removed in Exim 4.80, instead use
149 tls_require_ciphers to provide a priority string; see notes above]
151 * The match_<type>{string1}{string2} expansion conditions no longer subject
152 string2 to string expansion, unless Exim was built with the new
153 "EXPAND_LISTMATCH_RHS" option. Too many people have inadvertently created
154 insecure configurations that way. If you need the functionality and turn on
155 that build option, please let the developers know, and know why, so we can
156 try to provide a safer mechanism for you.
158 The match{}{} expansion condition (for regular expressions) is NOT affected.
159 For match_<type>{s1}{s2}, all list functionality is unchanged. The only
160 change is that a '$' appearing in s2 will not trigger expansion, but instead
161 will be treated as a literal $ sign; the effect is very similar to having
162 wrapped s2 with \N...\N. If s2 contains a named list and the list definition
163 uses $expansions then those _will_ be processed as normal. It is only the
164 point at which s2 is read where expansion is inhibited.
166 If you are trying to test if two email addresses are equal, use eqi{s1}{s2}.
167 If you are testing if the address in s1 occurs in the list of items given
168 in s2, either use the new inlisti{s1}{s2} condition (added in 4.77) or use
169 the pre-existing forany{s2}{eqi{$item}{s1}} condition.
175 * The integrated support for dynamically loadable lookup modules has an ABI
176 change from the modules supported by some OS vendors through an unofficial
177 patch. Don't try to mix & match.
179 * Some parts of the build system are now beginning to assume that the host
180 environment is POSIX. If you're building on a system where POSIX tools are
181 not the default, you might have an easier time if you switch to the POSIX
182 tools. Feel free to report non-POSIX issues as a request for a feature
183 enhancement, but if the POSIX variants are available then the fix will
184 probably just involve some coercion. See the README instructions for
185 building on such hosts.
191 * The Exim run-time user can no longer be root; this was always
192 strongly discouraged, but is now prohibited both at build and
193 run-time. If you need Exim to run routinely as root, you'll need to
194 patch the source and accept the risk. Here be dragons.
196 * Exim will no longer accept a configuration file owned by the Exim
197 run-time user, unless that account is explicitly the value in
198 CONFIGURE_OWNER, which we discourage. Exim now checks to ensure that
199 files are not writeable by other accounts.
201 * The ALT_CONFIG_ROOT_ONLY build option is no longer optional and is forced
202 on; the Exim user can, by default, no longer use -C/-D and retain privilege.
203 Two new build options mitigate this.
205 * TRUSTED_CONFIG_LIST defines a file containing a whitelist of config
206 files that are trusted to be selected by the Exim user; one per line.
207 This is the recommended approach going forward.
209 * WHITELIST_D_MACROS defines a colon-separated list of macro names which
210 the Exim run-time user may safely pass without dropping privileges.
211 Because changes to this involve a recompile, this is not the recommended
212 approach but may ease transition. The values of the macros, when
213 overridden, are constrained to match this regex: ^[A-Za-z0-9_/.-]*$
215 * The system_filter_user option now defaults to the Exim run-time user,
216 rather than root. You can still set it explicitly to root and this
217 can be done with prior versions too, letting you roll versions
218 without needing to change this configuration option.
220 * ClamAV must be at least version 0.95 unless WITH_OLD_CLAMAV_STREAM is
221 defined at build time.
227 1. Experimental Yahoo! Domainkeys support has been dropped in this release.
228 It has been superceded by a native implementation of its successor DKIM.
230 2. Up to version 4.69, Exim came with an embedded version of the PCRE library.
231 As of 4.70, this is no longer the case. To compile Exim, you will need PCRE
232 installed. Most OS distributions have ready-made library and development
239 1. The internal implementation of the database keys that are used for ACL
240 ratelimiting has been tidied up. This means that an update to 4.68 might cause
241 Exim to "forget" previous rates that it had calculated, and reset them to zero.
247 1. Callouts were setting the name used for EHLO/HELO from $smtp_active_
248 hostname. This is wrong, because it relates to the incoming message (and
249 probably the interface on which it is arriving) and not to the outgoing
250 callout (which could be using a different interface). This has been
251 changed to use the value of the helo_data option from the smtp transport
252 instead - this is what is used when a message is actually being sent. If
253 there is no remote transport (possible with a router that sets up host
254 addresses), $smtp_active_hostname is used. This change is mentioned here in
255 case somebody is relying on the use of $smtp_active_hostname.
257 2. A bug has been fixed that might just possibly be something that is relied on
258 in some configurations. In expansion items such as ${if >{xxx}{yyy}...} an
259 empty string (that is {}) was being interpreted as if it was {0} and therefore
260 treated as the number zero. From release 4.64, such strings cause an error
261 because a decimal number, possibly followed by K or M, is required (as has
262 always been documented).
264 3. There has been a change to the GnuTLS support (ChangeLog/PH/20) to improve
265 Exim's performance. Unfortunately, this has the side effect of being slightly
266 non-upwards compatible for versions 4.50 and earlier. If you are upgrading from
267 one of these earlier versions and you use GnuTLS, you must remove the file
268 called gnutls-params in Exim's spool directory. If you don't do this, you will
271 TLS error on connection from ... (DH params import): Base64 decoding error.
273 Removing the file causes Exim to recompute the relevant encryption parameters
274 and cache them in the new format that was introduced for release 4.51 (May
275 2005). If you are upgrading from release 4.51 or later, there should be no
282 When an SMTP error message is specified in a "message" modifier in an ACL, or
283 in a :fail: or :defer: message in a redirect router, Exim now checks the start
284 of the message for an SMTP error code. This consists of three digits followed
285 by a space, optionally followed by an extended code of the form n.n.n, also
286 followed by a space. If this is the case and the very first digit is the same
287 as the default error code, the code from the message is used instead. If the
288 very first digit is incorrect, a panic error is logged, and the default code is
289 used. This is an incompatible change, but it is not expected to affect many (if
290 any) configurations. It is possible to suppress the use of the supplied code in
291 a redirect router by setting the smtp_error_code option false. In this case,
292 any SMTP code is quietly ignored.
298 1. The default number of ACL variables of each type has been increased to 20,
299 and it's possible to compile Exim with more. You can safely upgrade to this
300 release if you already have messages on the queue with saved ACL variable
301 values. However, if you downgrade from this release with messages on the queue,
302 any saved ACL values they may have will be lost.
304 2. The default value for rfc1413_query_timeout has been changed from 30s to 5s.
310 There was a problem with 4.52/TF/02 in that a "name=" option on control=
311 submission terminated at the next slash, thereby not allowing for slashes in
312 the name. This has been changed so that "name=" takes the rest of the string as
313 its data. It must therefore be the last option.
319 If you are using the experimental Domain Keys support, you must upgrade to
320 at least libdomainkeys 0.67 in order to run this release of Exim.
326 1. The format in which GnuTLS parameters are cached (in the file gnutls-params
327 in the spool directory) has been changed. The new format can also be generated
328 externally, so it is now possible to update the values from outside Exim. This
329 has been implemented in an upwards, BUT NOT downwards, compatible manner.
330 Upgrading should be seamless: when Exim finds that it cannot understand an
331 existing cache file, it generates new parameters and writes them to the cache
332 in the new format. If, however, you downgrade from 4.51 to a previous release,
333 you MUST delete the gnutls-params file in the spool directory, because the
334 older Exim will not recognize the new format.
336 2. When doing a callout as part of verifying an address, Exim was not paying
337 attention to any local part prefix or suffix that was matched by the router
338 that accepted the address. It now behaves in the same way as it does for
339 delivery: the affixes are removed from the local part unless
340 rcpt_include_affixes is set on the transport. If you have a configuration that
341 uses prefixes or suffixes on addresses that could be used for callouts, and you
342 want the affixes to be retained, you must make sure that rcpt_include_affixes
343 is set on the transport.
345 3. Bounce and delay warning messages no longer contain details of delivery
346 errors, except for explicit messages (e.g. generated by :fail:) and SMTP
347 responses from remote hosts.
353 The exicyclog script has been updated to use three-digit numbers in rotated log
354 files if the maximum number to keep is greater than 99. If you are already
355 keeping more than 99, there will be an incompatible change when you upgrade.
356 You will probably want to rename your old log files to the new form before
357 running the new exicyclog.
363 RFC 3848 specifies standard names for the "with" phrase in Received: header
364 lines when AUTH and/or TLS are in use. This is the "received protocol"
365 field. Exim used to use "asmtp" for authenticated SMTP, without any
366 indication (in the protocol name) for TLS use. Now it follows the RFC and
367 uses "esmtpa" if the connection is authenticated, "esmtps" if it is
368 encrypted, and "esmtpsa" if it is both encrypted and authenticated. These names
369 appear in log lines as well as in Received: header lines.
375 Change 4.31/2 gave problems to data ACLs and local_scan() functions that
376 expected to see a Received: header. I have changed to yet another scheme. The
377 Received: header is now generated after the body is received, but before the
378 ACL or local_scan() is called. After they have run, the timestamp in the
379 Received: header is updated.
381 Thus, change (a) of 4.31/2 has been reversed, but change (b) is still true,
382 which is lucky, since I decided it was a bug fix.
388 If an expansion in a condition on a "warn" statement fails because a lookup
389 defers, the "warn" statement is abandoned, and the next ACL statement is
390 processed. Previously this caused the whole ACL to be aborted.
396 Change 4.31/2 has been reversed, as it proved contentious. Recipient callout
397 verification now uses <> in the MAIL command by default, as it did before. A
398 new callout option, "use_sender", has been added to request the other
405 1. If you compile Exim to use GnuTLS, it now requires the use of release 1.0.0
406 or greater. The interface to the obsolete 0.8.x releases is no longer
407 supported. There is one externally visible change: the format for the
408 display of Distinguished Names now uses commas as a separator rather than a
409 slash. This is to comply with RFC 2253.
411 2. When a message is received, the Received: header line is now generated when
412 reception is complete, instead of at the start of reception. For messages
413 that take a long time to come in, this changes the meaning of the timestamp.
414 There are several side-effects of this change:
416 (a) If a message is rejected by a DATA or non-SMTP ACL, or by local_scan(),
417 the logged header lines no longer include the local Received: line,
418 because it has not yet been created. If the message is a non-SMTP one,
419 and the error is processed by sending a message to the sender, the copy
420 of the original message that is returned does not have an added
423 (b) When a filter file is tested using -bf, no additional Received: header
424 is added to the test message. After some thought, I decided that this
427 The contents of $received_for are not affected by this change. This
428 variable still contains the single recipient of a message, copied after
429 addresses have been rewritten, but before local_scan() is run.
431 2. Recipient callout verification, like sender verification, was using <> in
432 the MAIL FROM command. This isn't really the right thing, since the actual
433 sender may affect whether the remote host accepts the recipient or not. I
434 have changed it to use the actual sender in the callout; this means that
435 the cache record is now keyed on a recipient/sender pair, not just the
436 recipient address. There doesn't seem to be a real danger of callout loops,
437 since a callout by the remote host to check the sender would use <>.
443 1. I have abolished timeout_DNS as an error that can be detected in retry
444 rules, because it has never worked. Despite the fact that it has been
445 documented since at least release 1.62, there was no code to support it.
446 If you have used it in your retry rules, you will now get a warning message
447 to the log and panic log. It is now treated as plain "timeout".
449 2. After discussion on the mailing list, Exim no longer adds From:, Date:, or
450 Message-Id: header lines to messages that do not originate locally, that is,
451 messages that have an associated sending host address.
453 3. When looking up a host name from an IP address, Exim now tries the DNS
454 first, and only if that fails does it use gethostbyaddr() (or equivalent).
455 This change was made because on some OS, not all the names are given for
456 addresses with multiple PTR records via the gethostbyaddr() interface. The
457 order of lookup can be changed by setting host_lookup_order.
463 1. The new FIXED_NEVER_USERS build-time option creates a list of "never users"
464 that cannot be overridden. The default in the distributed EDITME is "root".
465 If for some reason you were (against advice) running deliveries as root, you
466 will have to ensure that FIXED_NEVER_USERS is not set in your
469 2. The ${quote: operator now quotes an empty string, which it did not before.
471 3. Version 4.23 saves the contents of the ACL variables with the message, so
472 that they can be used later. If one of these variables contains a newline,
473 there will be a newline character in the spool that will not be interpreted
474 correctely by a previous version of Exim. (Exim ignores keyed spool file
475 items that it doesn't understand - precisely for this kind of problem - but
476 it expects them all to be on one line.)
478 So the bottom line is: if you have newlines in your ACL variables, you
479 cannot retreat from 4.23.
485 1. The idea of the "warn" ACL verb is that it adds a header or writes to the
486 log only when "message" or "log_message" are set. However, if one of the
487 conditions was an address verification, or a call to a nested ACL, the
488 messages generated by the underlying test were being passed through. This
489 no longer happens. The underlying message is available in $acl_verify_
490 message for both "message" and "log_message" expansions, so it can be
491 passed through if needed.
493 2. The way that the $h_ (and $header_) expansions work has been changed by the
494 addition of RFC 2047 decoding. See the main documentation (the NewStuff file
495 until release 4.30, then the manual) for full details. Briefly, there are
498 $rh_xxx: and $rheader_xxx: give the original content of the header
499 line(s), with no processing at all.
501 $bh_xxx: and $bheader_xxx: remove leading and trailing white space, and
502 then decode base64 or quoted-printable "words" within the header text,
503 but do not do charset translation.
505 $h_xxx: and $header_xxx: attempt to translate the $bh_ string to a
506 standard character set.
508 If you have previously been using $h_ expansions to access the raw
509 characters, you should change to $rh_ instead.
511 3. When Exim creates an RFC 2047 encoded word in a header line, it labels it
512 with the default character set from the headers_charset option instead of
513 always using iso-8859-1.
515 4. If TMPDIR is defined in Local/Makefile (default in src/EDITME is
516 TMPDIR="/tmp"), Exim checks for the presence of an environment variable
517 called TMPDIR, and if it finds it is different, it changes its value.
519 5. Following a discussion on the list, the rules by which Exim recognises line
520 endings on incoming messages have been changed. The -dropcr and drop_cr
521 options are now no-ops, retained only for backwards compatibility. The
522 following line terminators are recognized: LF CRLF CR. However, special
523 processing applies to CR:
525 (i) The sequence CR . CR does *not* terminate an incoming SMTP message,
526 nor a local message in the state where . is a terminator.
528 (ii) If a bare CR is encountered in a header line, an extra space is added
529 after the line terminator so as not to end the header. The reasoning
530 behind this is that bare CRs in header lines are most likely either
531 to be mistakes, or people trying to play silly games.
533 6. The code for using daemon_smtp_port, local_interfaces, and the -oX options
534 has been reorganized. It is supposed to be backwards compatible, but it is
535 mentioned here just in case I've screwed up.
542 1. I have tidied and re-organized the code that uses alarm() for imposing time
543 limits on various things. It shouldn't affect anything, but if you notice
544 processes getting stuck, it may be that I've broken something.
546 2. The "arguments" log selector now also logs the current working directory
549 3. An incompatible change has been made to the appendfile transport. This
550 affects the case when it is used for file deliveries that are set up by
551 .forward and filter files. Previously, any settings of the "file" or
552 "directory" options were ignored. It is hoped that, like the address_file
553 transport in the default configuration, these options were never in fact set
554 on such transports, because they were of no use.
556 Now, if either of these options is set, it is used. The path that is passed
557 by the router is in $address_file (this is not new), so it can be used as
558 part of a longer path, or modified in any other way that expansion permits.
560 If neither "file" nor "directory" is set, the behaviour is unchanged.
562 4. Related to the above: in a filter, if a "save" command specifies a non-
563 absolute path, the value of $home/ is pre-pended. This no longer happens if
564 $home is unset or is set to an empty string.
566 5. Multiple file deliveries from a filter or .forward file can never be
567 batched; the value of batch_max on the transport is ignored for file
568 deliveries. I'm assuming that nobody ever actually set batch_max on the
569 address_file transport - it would have had odd effects previously.
571 6. DESTDIR is the more common variable that ROOT for use when installing
572 software under a different root filing system. The Exim install script now
573 recognizes DESTDIR first; if it is not set, ROOT is used.
575 7. If DESTDIR is set when installing Exim, it no longer prepends its value to
576 the path of the system aliases file that appears in the default
577 configuration (when a default configuration is installed). If an aliases
578 file is actually created, its name *does* use the prefix.
584 1. The default for the maximum number of unknown SMTP commands that Exim will
585 accept before dropping a connection has been reduced from 5 to 3. However, you
586 can now change the value by setting smtp_max_unknown_commands.
588 2. The ${quote: operator has been changed so that it turns newline and carriage
589 return characters into \n and \r, respectively.
591 3. The file names used for maildir messages now include the microsecond time
592 fraction as well as the time in seconds, to cope with systems where the process
593 id can be re-used within the same second. The format is now
595 <time>.H<microsec>P<pid>.<host>
597 This should be a compatible change, but is noted here just in case.
599 4. The rules for creating message ids have changed, to cope with systems where
600 the process id can be re-used within the same second. The format, however, is
601 unchanged, so this should not cause any problems, except as noted in the next
604 5. The maximum value for localhost_number has been reduced from 255 to 16, in
605 order to implement the new message id rules. For operating systems that have
606 case-insensitive file systems (Cygwin and Darwin), the limit is 10.
608 6. verify = header_syntax was allowing unqualified addresses in all cases. Now
609 it allows them only for locally generated messages and from hosts that match
610 sender_unqualified_hosts or recipient_unqualified_hosts, respectively.
612 7. For reasons lost in the mists of time, when a pipe transport was run, the
613 environment variable MESSAGE_ID was set to the message ID preceded by 'E' (the
614 form used in Message-ID: header lines). The 'E' has been removed.
620 1. The handling of lines in the configuration file has changed. Previously,
621 macro expansion was applied to logical lines, after continuations had been
622 joined on. This meant that it could not be used in .include lines, which are
623 handled as physical rather than logical lines. Macro expansion is now done on
624 physical lines rather than logical lines. This means there are two
627 (a) A macro that expands to # to turn a line into a comment now applies only
628 to the physical line where it appears. Previously, it would have caused
629 any following continuations also to be ignored.
631 (b) A macro name can no longer be split over the boundary between a line and
632 its continuation. Actually, this is more of a bug fix. :-)
634 2. The -D command line option must now all be within one command line item.
635 This makes it possible to use -D to set a macro to the empty string by commands
641 Previously, these items would have moved on to the next item on the command
642 line. To include spaces in a macro definition item, quotes must be used, in
643 which case you can also have spaces after -D and surrounding the equals. For
646 exim '-D ABC = something' ...
648 3. The way that addresses that redirect to themselves are handled has been
649 changed, in order to fix an obscure bug. This should not cause any problems
650 except in the case of wanting to go back from a 4.11 (or later) release to an
651 earlier release. If there are undelivered messages on the spool that contain
652 addresses which redirect to themselves, and the redirected addresses have
653 already been delivered, you might get a duplicate delivery if you revert to an
656 4. The default way of looking up IP addresses for hosts in the manualroute and
657 queryprogram routers has been changed. If "byname" or "bydns" is explicitly
658 specified, there is no change, but if no method is specified, Exim now behaves
661 First, a DNS lookup is done. If this yields anything other than
662 HOST_NOT_FOUND, that result is used. Otherwise, Exim goes on to try a call to
663 getipnodebyname() (or gethostbyname() on older systems) and the result of the
664 lookup is the result of that call.
666 This change has been made because it has been discovered that on some systems,
667 if a DNS lookup called via getipnodebyname() times out, HOST_NOT_FOUND is
668 returned instead of TRY_AGAIN. Thus, it is safest to try a DNS lookup directly
669 first, and only if that gives a definite "no such host" to try the local
672 5. In fixing the minor security problem with pid_file_path, I have removed some
673 backwards-compatible (undocumented) code which was present to ease conversion
674 from Exim 3. In Exim 4, pid_file_path is a literal; in Exim 3 it was allowed to
675 contain "%s", which was replaced by the port number for daemons listening on
676 non-standard ports. In Exim 4, such daemons do not write a pid file. The
677 backwards compatibility feature was to replace "%s" by nothing if it occurred
678 in an Exim 4 setting of pid_file_path. The bug was in this code. I have solved
679 the problem by removing the backwards compatibility feature. Thus, if you still
680 have "%s" somewhere in a setting of pid_file_path, you should remove it.
682 6. There has been an extension to lsearch files. The keys in these files may
683 now be quoted in order to allow for whitespace and colons in them. This means
684 that if you were previously using keys that began with a doublequote, you will
685 now have to wrap them with extra quotes and escape the internal quotes. The
686 possibility that anybody is actually doing this seems extremely remote, but it
687 is documented just in case.
693 The build-time parameter EXIWHAT_KILL_ARG has been renamed EXIWHAT_KILL_SIGNAL
694 to better reflect its function. The OS-specific files have been updated. Only
695 if you have explicitly set this in your Makefile (highly unlikely) do you need
git://git.exim.org / exim.git / blob