1 .\" Copyright (c) 1980, 1990, 1993
2 .\" The Regents of the University of California. All rights reserved.
4 .\" Gunnar Ritter. All rights reserved.
5 .\" Copyright (c) 2012 - 2015 Steffen (Daode) Nurpmeso <sdaoden@users.sf.net>.
7 .\" Redistribution and use in source and binary forms, with or without
8 .\" modification, are permitted provided that the following conditions
10 .\" 1. Redistributions of source code must retain the above copyright
11 .\" notice, this list of conditions and the following disclaimer.
12 .\" 2. Redistributions in binary form must reproduce the above copyright
13 .\" notice, this list of conditions and the following disclaimer in the
14 .\" documentation and/or other materials provided with the distribution.
15 .\" 3. All advertising materials mentioning features or use of this software
16 .\" must display the following acknowledgement:
17 .\" This product includes software developed by the University of
18 .\" California, Berkeley and its contributors.
19 .\" This product includes software developed by Gunnar Ritter
20 .\" and his contributors.
21 .\" 4. Neither the name of the University nor the names of its contributors
22 .\" may be used to endorse or promote products derived from this software
23 .\" without specific prior written permission.
25 .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS 'AS IS' AND
26 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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38 .\" S-nail(1): v14.8.5 / 2015-09-05
50 .\" If not ~/.mailrc, it breaks POSIX compatibility. And adjust main.c.
55 .ds OU [no v15-compat]
56 .ds ID [v15 behaviour may differ]
67 .Nd send and receive Internet mail
79 .Op Fl a Ar attachment
82 .Op Fl q Ar quote-file
84 .Op Fl S Ar variable Ns Op Ns = Ns Ar value
89 .Op Fl Fl \: Ar mta-option ...
97 .Op Fl S Ar variable Ns Op Ns = Ns Ar value
100 .Op Fl Fl \: Ar mta-option ...
106 .Op Fl L Ar spec-list
107 .Op Fl r Ar from-addr
108 .Op Fl S Ar variable Ns Op Ns = Ns Ar value
111 .Op Fl Fl \: Ar mta-option ...
116 .Mx -toc -tree html pdf ps xhtml
119 .\" .Sh DESCRIPTION {{{
122 .Bd -filled -compact -offset indent
123 .Sy Compatibility note:
124 \*(UA and part of its configuration syntax will change in v15.0.
125 Until then there will exist a partial but growing number of
126 backward and forward compatibility configuration options.
127 To choose the new syntax and behaviour already today, the binary option
130 The manual will refer to it via \*(IN and \*(OU as necessary.
131 Commands and variables which will vanish in v15.0 are marked \*(OB.
135 \*(UA is a mail processing system with a command syntax reminiscent of
137 with lines replaced by messages.
138 It is intended to provide the functionality of the POSIX
140 command and offers (mostly optional) extensions for line editing, IDNA,
141 MIME, S/MIME, SMTP and POP3 (and IMAP).
142 It is usable as a mail batch language.
144 .\" .Ss "Options" {{{
147 .Bl -tag -width ".Fl _ Ar _ccount"
152 command (see below) for
154 after the startup files have been read.
158 Attach the given file to the message.
159 The same filename conventions as described in the section
161 apply: shell word expansion is restricted to the tilde
166 not be accessible but contain a
168 character, then anything after the
170 is assumed to specify the input character set and anything before
172 the filename: this is the only option to specify the input character set
173 (and don't perform any character set conversion) for text attachments
174 from the command line, not using the
176 tilde escape command.
180 Make standard input and standard output line-buffered.
184 Send blind carbon copies to the given list of addresses.
186 below goes into more detail on that.
190 Send carbon copies to the given list of addresses.
202 variable, which enables debug messages and disables message delivery.
208 variable and thus discard messages with an empty message part body.
209 This is useful for sending messages from scripts.
213 Just check if mail is present in the system mailbox.
214 If yes, return an exit status of zero, a non-zero value otherwise.
218 Save the message to send in a file named after the local part of the
219 first recipient's address (instead of in
224 Read in the contents of the user's
226 (or the specified file) for processing;
227 when \*(UA is quit, it writes undeleted messages back to this file
231 Some special conventions are recognized for the string
233 which are documented for the
238 is not a direct argument to the flag
240 but is instead taken from the command line after option processing has
244 that starts with a hyphen, prefix it with a (relative) path, as in
245 .Ql ./-hyphenbox.mbox .
249 Print a header summary of all messages and exit.
250 A configurable summary view is available via the
256 Print a short usage summary.
257 Because of widespread use a
259 argument will have the same effect.
265 variable to ignore tty interrupt signals.
268 .It Fl L Ar spec-list
269 Print a header summary of only those messages that match the given
273 .Sx "Specifying messages"
278 option has been given in addition no header summary is produced,
279 but \*(UA will instead indicate via its exit status wether
285 note that any verbose output is suppressed in this mode and must instead
286 be enabled explicitly (e.g., by using the option
293 variable and thus inhibit initial display of message headers when
294 reading mail or editing a mail folder.
301 This option should be activated for \*(UA scripts that are invoked on
302 more than one machine, because the contents of that file may differ
304 (The same behaviour can be achieved by setting the
305 .Ev NAIL_NO_SYSTEM_RC
306 environment variable.)
310 Start the message with the contents of the specified file.
311 May be given in send mode only.
315 Any folder opened will be in read-only mode.
321 is a valid address then it specifies the envelope sender address to be
324 when a message is send.
327 include a user name, comments etc., then the components will be
328 separated and the name part will be passed to the MTA individually via
332 will also be assigned to the
334 variable, just as if additionally
336 had been specified (therefore affecting SMTP data transfer, too).
338 If instead an empty string is passed as
340 then the content of the variable
342 will be evaluated and used for this purpose whenever the MTA is
344 Note that \*(UA by default, without
346 that is, neither passes
350 flags to the MTA by itself.
353 .It Fl S Ar variable Ns Op = Ns value
354 Sets the internal option
356 and, in case of a value option, assigns
359 Even though options set via
361 may be overwritten from within resource files,
362 the command line setting will be reestablished after all resource files
367 Specify the subject of the to-be-sent message.
371 The message to be sent is expected to contain a message header with
376 fields giving its recipients, which will be added to those given on the
378 If a message subject is specified via
380 then it'll be used in favour of one given on the command line.
392 Note you can also specify
396 and the envelope address possibly specified with the option
399 The following, which are normally created automatically based
400 upon the message context, can also be specified:
405 .Ql Mail-Followup-To:
406 (special address massage will however still occur for the latter).
410 Read the system mailbox of
412 (appropriate privileges presumed), and
415 in some aspects, e.g. in respect to
424 Print \*(UA's version and exit.
430 option causes some verbosity (like printing of certificate chains).
431 Using it twice increases the level of verbosity.
437 to the list of commands to be executed before normal operation starts.
441 .Va batch-exit-on-error ;
442 the only possibility to execute commands in non-interactive mode when
443 reading startup files is actively prohibited.
449 even if not in interactive mode.
453 This sets several options to prepare \*(UA for working in (most likely
454 non-interactive) batch mode:
466 It also enables processing of
467 .Sx "TILDE ESCAPES" .
468 E.g., the following should send an email message to
470 .Bd -literal -offset indent
471 $ LC_ALL=C printf 'm bob\en~s ubject\enText\en.\enx\en' | \e
472 LC_ALL=C MAILRC=/dev/null s-nail -n -# -Snosave
477 This flag forces termination of option processing in order to prevent
480 It also forcefully puts \*(UA into send mode, see
485 In the above list of supported command line options,
486 .Fl D , d , E , i , N
489 are implemented by means of setting the respective option, as via
492 .Op Ar mta-option ...
494 arguments that are given at the end of the command line after a
496 separator will be passed through to the mail-transfer-agent (MTA) and
497 persist for an entire (interactive) session \(en if the setting of
499 allows their recognition;
500 MTA arguments can also be specified in the variable
501 .Va sendmail-arguments ;
502 find MTA interaction described in more detail in the documentation of
504 MTA arguments are ignored when mail is send via SMTP data transfer.
507 .\" .Ss "A starter" {{{
510 \*(UA is a direct descendant of the BSD Mail program that was introduced
511 in 1978 (itself superceeding the simpler UNIX mail program) and used
512 to introduce itself (in the Mail reference manual) as follows:
514 .Bd -ragged -offset indent
515 Mail provides a simple and friendly environment for sending and
517 It divides incoming mail into its constituent messages and allows the
518 user to deal with them in any order.
519 In addition, it provides a set of
521 -like commands for manipulating messages and sending mail.
522 Mail offers the user simple editing capabilities to ease the composition
523 of outgoing messages, as well as providing the ability to define and
524 send to names which address groups of users.
528 \*(UA is thus the user side of the Unix mail system, whereas the system
529 side (mail-transfer-agent, MTA) was traditionally taken by
535 are often used for this purpose instead.
536 If the \*(OPal SMTP feature has been built into \*(UA then the
537 system side is not a mandatory precondition for mail delivery.
540 Because \*(UA strives for compliance with POSIX
542 it is likely that some configuration settings have to be adjusted before
543 using it is a smooth experience.
546 file already bends those standard settings a bit towards more user
547 friendliness and safety, e.g., it sets the
551 options in order to suppress the automatic moving of messages to
553 that would otherwise occur (see
554 .Sx "Message states" )
557 to not remove empty files in order not to mangle file permissions when
558 files eventually get recreated.
561 option so that by default file grouping (via the
563 prefix as documented also for
568 contains some further suggestions.
571 .\" .Ss "Sending mail" {{{
574 To send a message to one or more people, using a local
575 mail-transfer-agent (MTA; the executable path can be set via
577 or the \*(OPal builtin SMTP (set and see the variable
579 transport to actually deliver the generated mail message, \*(UA can be
580 invoked with arguments which are the names of people to whom the mail
583 .Bd -literal -offset indent
584 $ \*(ua -s Subject -a attachm.ent bill@host1 'Bob <bob@host2>'
585 # But... try it in an isolated dry-run mode first
586 $ LC_ALL=C MAILRC=/dev/null \e
587 \*(ua -n -d -vv -Sfrom="me <he@re>" \e
588 -s Subject -. "(Lovely) Bob <bob@host2>"
592 The user is then expected to type in the message contents.
593 In this compose mode \*(UA treats lines beginning with the character
595 special \(en these are so-called
597 which can be used to read in files, process shell commands, add and edit
598 attachments and more; e.g., the tilde escape
600 will start the text editor to revise the message in it's current state,
602 allows editing of the message recipients and
604 gives an overview of available tilde escapes.
607 at the beginning of an empty line leaves compose mode and causes the
608 message to be send, whereas typing control-C
610 twice will abort the current letter (saving its contents in the file
618 A number of options can be used to alter default behavior; e.g.,
623 will automatically startup a text editor when compose mode is entered,
625 will cause the user to be prompted actively for carbon-copy recipients
628 option will allow leaving compose mode by writing a line consisting
633 Very important, though, is to define which
635 may be used when sending messages, usually by setting the option
638 having read the section
639 .Sx "The mime.types files"
640 to understand how the MIME-type of outgoing attachments is classified
641 and the knowledge that messages are sent asynchronously unless
643 is set: only with it MTA delivery errors will be recognizable.
648 is often necessary (e.g., in conjunction with
650 or desirable, you may want to do some dry-run tests before you go.
651 Saving a copy of the sent messages in a
653 may also be desirable \(en as for most mailbox file targets some
654 special conventions are recognized, see the
656 command for more on that.
658 .Sx "On URL syntax and credential lookup"
659 will spread some light on the
661 variable chains as well as on using URLs for accessing protocol-specific
666 contains an example configuration for sending messages via some of the
667 well-known public mail providers;
668 note it also gives a compact overview on how to setup a secure SSL/TLS
672 Message recipients (as specified on the command line or defined in
677 may not only be email addressees but can also be names of mailboxes and
678 even complete shell command pipe specifications.
679 Proper quoting may be necessary, e.g., to embed whitespace characters.
680 (Recall that \*(UA deals with mail standards, therefore those define the
681 rules with which content is interpreted.)
684 is not set then only network addresses (see
686 for a description of mail addresses) and plain user names (including MTA
687 aliases) may be used, other types will be filtered out, giving a warning
690 .\" When changing any of the following adjust any RECIPIENTADDRSPEC;
691 .\" grep the latter for the complete picture
695 is set then extended recipient addresses will optionally be accepted:
696 Any name which starts with a vertical bar
698 character specifies a command pipe \(en the command string following the
700 is executed and the message is sent to its standard input;
701 Likewise, any name that starts with the character slash
703 or the character sequence dot slash
705 is treated as a file, regardless of the remaining content.
706 Any other name which contains an at sign
708 character is treated as a network address;
709 Any other name which starts with a plus sign
711 character specifies a mailbox name;
712 Any other name which contains a slash
714 character but no exclamation mark
718 character before also specifies a mailbox name;
719 What remains is treated as a network address.
721 .Bd -literal -offset indent
722 $ echo bla | \*(ua -Sexpandaddr -s test ./mbox.mbox
723 $ echo bla | \*(ua -Sexpandaddr -s test '|cat >> ./mbox.mbox'
724 $ echo safe | LC_ALL=C MAILRC=/dev/null \e
725 \*(ua -n -Sv15-compat -Ssendwait -Snosave \e
726 -Sexpandaddr=fail,-all,+addr -s test \e
731 It is possible to create personal distribution lists via the
733 command, so that, for instance, the user can send mail to
735 and have it go to a group of people:
738 .Dl alias cohorts bill jkf mark kridle@ucbcory ~/mail/cohorts.mbox
741 Please note that this mechanism has nothing in common with the system
742 wide aliases that may be used by the local MTA (mail-transfer-agent),
743 which are subject to the
747 and are often tracked in a file
753 Personal aliases will be expanded by \*(UA before the message is sent,
754 and are thus a convenient alternative to specifying each addressee by
758 To avoid environmental noise scripts should
760 \*(ua from any configuration files and create a script-local
761 environment, either by pointing the
763 variable to a custom configuration file, or by using the
765 command line option to specify options:
767 .Bd -literal -offset indent
768 $ env LC_ALL=C MAILRC=/dev/null password=NOTSECRET \e
769 \*(ua -n -Sv15-compat -Ssendwait -Snosave \e
770 -Sexpandaddr=fail,-all,+addr \e
771 -S 'smtp=smtps://mylogin@some.host:465' -Ssmtp-auth=login \e
772 -S 'from=scriptreply@domain' \e
773 -s 'subject' -a attachment_file \e
774 -. "Recipient 1 <recipient1@domain>" recipient2@domain \e
779 .\" .Ss "Reading mail" {{{
782 When invoked without addressees \*(UA enters interactive mode in which
784 When used like that the user's system mailbox is read in and a one line
785 header of each message therein is printed.
788 for an in-depth description of the different mailbox types that exist.)
789 Note that if the mailbox is empty \*(UA will exit after printing
790 a message unless the option
799 will give a listing of all available commands and
801 will give a summary of some common ones.
802 If the \*(OPal documentation strings are available one can type
804 and see the actual expansion of
806 and what it's purpose is, i.e., commands can be abbreviated
807 (note that POSIX defines some abbreviations, so that the alphabetical
808 order of commands doesn't necessarily relate to the abbreviations; it is
809 possible to define overwrites with the
814 Messages are given numbers (starting at 1) which uniquely identify
815 messages; the current message \(en the
817 \(en will either be the first new message, or the first unread message,
818 or the first message of the mailbox; the option
820 will instead cause usage of the last message for this purpose.
823 Messages can be printed with the
827 By default the current message
829 is printed, but like with most other commands it is possible to give
830 a fancy message specification (see
831 .Sx "Specifying messages" ) ,
834 will display all unread messages,
839 will print the messages 1 and 5,
841 will print the messages 1 through 5, and
845 will print the last and the next message, respectively.
848 In the default setup all header fields of a message will be printed,
849 but this can be changed: either by blacklisting a list of fields via
851 or by whitelisting only a given list with the
854 .Ql Ic \:retain Ns \0date from to cc subject .
855 In order to print all header fields of a message regardless of currently
856 active ignore or retain lists, use the command
860 controls wether and when \*(UA will use the configured
862 for printing instead of directly writing to the terminal (generally
866 Dependent upon the configuration a
867 .Sx "Command line editor"
868 aims at making user experience with the many
871 When reading the system mailbox or when
875 specified a mailbox explicitly prefixed with the special
877 modifier then messages which have been read will be moved to the user's
879 file automatically when the mailbox is left, either by changing the
880 active mailbox or by quitting \*(UA (also see
881 .Sx "Message states" ) .
884 After examining a message the user can also
888 to the sender and all recipients or
890 exclusively to the sender.
895 Note that when replying to or forwarding a message recipient addresses
896 will be stripped from comments and names unless the option
899 Deletion causes \*(UA to forget about the message;
900 This is not irreversible, though, one can
902 the message by giving its number,
903 or the \*(UA session can be ended by giving the
908 To end a mail processing session one may either issue
910 to cause a full program exit, which possibly includes
911 automatic moving of read messages to
913 as well as updating the \*(OPal command line editor history file,
916 instead in order to prevent any of these actions.
919 .\" .Ss "Viewing HTML mail and MIME attachments" {{{
920 .Ss "Viewing HTML mail and MIME attachments"
922 Messages which are HTML-only get more and more common and of course many
923 messages come bundled with a bouquet of MIME attachments.
924 Whereas \*(UA \*(OPally supports a simple HTML-to-text converter to deal
925 with HTML messages (see
926 .Sx "The mime.types files" ) ,
927 it normally can't deal with any of these itself, but instead programs
928 need to become registered to deal with specific MIME types or file
930 These programs may either prepare plain text versions of their input
931 in order to enable \*(UA to display the content on the terminal,
932 or display the content themselves, for example in a graphical window.
933 The latter type of programs by default
935 \*(UA until the external viewer has terminated, but asynchronous
936 side-by-side execution is also possible, in which case \*(UA will
937 continue to display the message and remain responsive.
940 To install an external handler program for a specific MIME type set an
942 .Va pipe-TYPE/SUBTYPE
944 To define a handler for a specific file extension set the respective
946 variable \(en these handlers take precedence.
948 .Va mime-counter-evidence
949 can be set to improve dealing with faulty MIME part declarations as are
950 often seen in real-life messages.
951 E.g., to display a HTML message inline (that is, converted to a more
952 fancy plain text representation than the builtin converter is capable to
953 produce) with either of the text-mode browsers
957 teach \*(UA about MathML documents and make it display them as plain text
958 and to open PDF attachments in an external PDF viewer, asynchronously:
960 .Bd -literal -offset indent
961 if $features !@ HTML-FILTER
962 #set pipe-text/html="elinks -force-html -dump 1"
963 set pipe-text/html="lynx -stdin -dump -force_html"
964 # Display HTML as plain text instead
965 #set pipe-text/html=@
967 mimetype '@ application/mathml+xml mathml'
968 set pipe-application/pdf="@&set -C;\e
969 : > \e"${TMPDIR}/${NAIL_FILENAME_GENERATED}\e"; \e
970 trap \e"rm -f \e\e\e"${TMPDIR}/${NAIL_FILENAME_GENERATED}\e\e\e"\e" \e
971 EXIT INT QUIT PIPE TERM;\e
973 cat > \e"${TMPDIR}/${NAIL_FILENAME_GENERATED}\e"; \e
974 xpdf \e"${TMPDIR}/${NAIL_FILENAME_GENERATED}\e""
978 Note: special care must be taken when using such commands as mail
979 viruses may be distributed by this method: if messages of type
981 or files with the extension
983 were blindly filtered through the shell, for example, a message sender
984 could easily execute arbitrary code on the system \*(UA is running on.
985 For more on MIME, also in respect to sending of messages, see the
987 .Sx "The mime.types files"
992 .\" .Ss "Mailing lists" {{{
995 \*(UA offers some support to ease handling of mailing lists.
998 promotes all given arguments to known mailing lists, and
1000 sets their subscription attribute, creating them first as necessary.
1005 automatically, but only resets the subscription attribute.)
1006 Using the commands without arguments will print out (a subset of) all
1007 currently defined mailing lists.
1012 can be used to mark out messages with configured list addresses
1013 in the header display.
1016 \*(OPally mailing lists may also be specified as regular expressions,
1017 which allows matching of many addresses with a single expression.
1018 However, all fully qualified list addresses are matched via a fast
1019 dictionary, whereas expressions are placed in (a) list(s) which is
1020 (are) matched sequentially.
1022 .Bd -literal -offset indent
1023 set followup-to followup-to-honour=ask-yes reply-to-honour=ask-yes
1024 mlist a1@b1.c1 a2@b2.c2 .*@lists.c3$
1025 mlsubscribe a4@b4.c4 exact@lists.c3
1030 .Va followup-to-honour
1032 .Ql Mail-\:Followup-\:To:
1033 header is honoured when the message is being replied to (via
1039 controls wether this header is created when sending mails; it will be
1040 created automatically for a couple of reasons, too, like when the
1042 .Dq mailing list specific
1047 is used to respond to a message with its
1048 .Ql Mail-Followup-To:
1052 A difference in between the handling of known and subscribed lists is
1053 that the address of the sender is usually not part of a generated
1054 .Ql Mail-Followup-To:
1055 when addressing the latter, whereas it is for the former kind of lists.
1056 Usually because there are exceptions: say, if multiple lists are
1057 addressed and not all of them are subscribed lists.
1059 For convenience \*(UA will, temporarily, automatically add a list
1060 address that is presented in the
1062 header of a message that is being responded to to the list of known
1064 Shall that header have existed \*(UA will instead, dependend on the
1066 .Va reply-to-honour ,
1069 for this purpose in order to accept a list administrators' wish that
1070 is supposed to have been manifested like that (but only if it provides
1071 a single address which resides on the same domain as what is stated in
1075 .\" .Ss "Resource files" {{{
1076 .Ss "Resource files"
1078 Upon startup \*(UA reads in several resource files:
1080 .Bl -tag -width ".It Pa _AIL_EXTRA_R_"
1083 System wide initialization file.
1084 Reading of this file can be suppressed, either by using the
1086 command line option, or by setting the environment variable
1087 .Ev NAIL_NO_SYSTEM_RC .
1091 File giving initial commands.
1092 A different file can be chosen by setting the environment variable
1095 .It Va NAIL_EXTRA_RC
1096 Can be used to define an optional startup file to be read after
1098 This variable is only honoured in certain circumstances (see its
1099 documentation for more).
1103 The content of these files is interpreted as follows:
1106 .Bl -bullet -compact
1108 A lines' leading whitespace is ignored.
1110 An empty line is ignored.
1112 If the line (content) starts with the number sign
1114 then it is a comment-command \(en a real command! \(en and also ignored.
1115 This command is the only form of comment that is understood.
1119 on the next line if the newline character is
1121 by preceding it with the backslash character
1123 Note that any leading whitespace of follow lines is removed:
1124 If whitespace is desired it must be placed before the backslash.
1127 .Bd -literal -offset indent
1128 # This line is a comment command. And y\e
1129 es, it is really continued here.
1136 .\" .Ss "Character sets" {{{
1137 .Ss "Character sets"
1139 \*(OP \*(UA detects the character set of the terminal by using
1140 mechanisms that are controlled by the
1145 should give an overview); the \*(UA internal variable
1147 will be set to the detected terminal character set accordingly
1148 and will thus show up in the output of the commands
1154 However, a user supplied
1156 value is not overwritten by this detection mechanism: this
1158 must be used if the detection doesn't work properly,
1159 and it may be used to adjust the name of the locale character set.
1160 E.g., on BSD systems one may use a locale with the character set
1161 ISO8859-1, which is not a valid name for this character set; to be on
1162 the safe side, one may set
1164 to the correct name, which is ISO-8859-1.
1167 Note that changing the value doesn't mean much beside that,
1168 since several aspects of the real character set are implied by the
1169 locale environment of the system,
1170 and that stays unaffected by the content of an overwritten
1173 (This is mostly an issue when interactively using \*(UA, though.
1174 It is actually possible to send mail in a completely
1176 locale environment.)
1179 If no character set conversion capabilities have been compiled into
1182 library has been found), then
1184 will be the only supported character set,
1185 it is simply assumed that it can be used to exchange 8-bit messages,
1186 and the rest of this section does not apply;
1187 it may however still be necessary to explicitly set it if automatic
1188 detection fails, since in that case it defaults to the mentioned
1192 When reading messages, their text is converted into
1194 as necessary in order to display them on the users terminal.
1195 Unprintable characters and invalid byte sequences are detected
1196 and replaced by proper substitution characters (unless the variable
1198 was set once \*(UA was started).
1200 .Va charset-unknown-8bit
1201 to deal with another hairy aspect of message interpretation.
1204 When sending messages all their parts and attachments are classified.
1205 Whereas no character set conversion is performed on those parts which
1206 appear to be binary data,
1207 the character set being used must be declared within the MIME header of
1208 an outgoing text part if it contains characters that do not conform to
1209 the set of characters that are allowed by the email standards.
1210 Permissible values for character sets can be declared using the
1214 which defines a catch-all last-resort fallback character set that is
1215 implicitly appended to the list of character-sets in
1219 When replying to a message and the variable
1220 .Va reply-in-same-charset
1221 is set then the character set of the message being replied to is tried
1223 And it is also possible to make \*(UA work even more closely related to
1224 the current locale setting automatically by using the variable
1225 .Va sendcharsets-else-ttycharset ,
1226 please see there for more information.
1229 All the specified character sets are tried in order unless the
1230 conversion of the part or attachment succeeds.
1231 If none of the tried (8-bit) character sets is capable to represent the
1232 content of the part or attachment,
1233 then the message will not be sent and its text will be saved to
1235 In general, if the message
1236 .Dq Cannot convert from a to b
1237 appears, either some characters are not appropriate for the currently
1238 selected (terminal) character set,
1239 or the needed conversion is not supported by the system.
1240 In the first case, it is necessary to set an appropriate
1242 locale and/or the variable
1246 The best results are usually achieved when \*(UA is run in a UTF-8
1247 locale on a UTF-8 capable terminal, in which case the full Unicode
1248 spectrum of characters is available.
1249 In this setup characters from various countries can be displayed,
1250 while it is still possible to use more simple character sets for sending
1251 to retain maximum compatibility with older mail clients.
1254 .\" .Ss "Message states" {{{
1255 .Ss "Message states"
1257 \*(UA differentiates in between several different message states;
1258 the current state will be reflected in the header display if
1260 is configured to do so.
1261 In \*(UA message states are inspected when leaving a mailbox and may
1262 cause messages to be automatically moved to the special
1264 mailbox \(en because this may be irritating to users which are used to
1266 mail-user-agents, the default global
1272 variables in order to suppress this behaviour.
1274 .Bl -tag -width ".It Ql _reserved"
1276 Message has neither been viewed nor moved to any other state.
1277 Such messages are retained even in the system mailbox.
1280 Message has neither been viewed nor moved to any other state, but the
1281 message was present already when the mailbox has been opened last:
1282 Such messages are retained even in the system mailbox.
1285 The message has been processed by one of the following commands:
1305 commands may also cause the next message to be marked as read, depending
1311 command is used, messages that are in the system mailbox or in mailboxes
1312 which were opened with the special
1316 state when the mailbox is left will be saved in
1323 The message has been processed by one of the following commands:
1329 can be used to access such messages.
1332 The message has been processed by a
1334 command and it will be retained in its current location.
1337 The message has been processed by one of the following commands:
1343 command is used, messages that are in the system mailbox or in mailboxes
1344 which were opened with the special
1348 state when the mailbox is left will be deleted; they will be saved in
1356 .\" .Ss "Specifying messages" {{{
1357 .Ss "Specifying messages"
1363 can be given a list of message numbers as arguments to apply to a number
1364 of messages at once.
1367 deletes messages 1 and 2,
1370 will delete the messages 1 through 5.
1371 In sorted or threaded mode (see the
1375 will delete the messages that are located between (and including)
1376 messages 1 through 5 in the sorted/threaded order, as shown in the
1378 Multiple colon modifiers can be joined into one, e.g.,
1380 The following special message names exist:
1382 .Bl -tag -width ".It Ar _n_u"
1388 All old messages (any not in state
1411 All answered messages
1416 All messages marked as draft.
1418 \*(OP All messages classified as spam.
1420 \*(OP All messages with unsure spam classification.
1422 The current message, the so-called
1425 The message that was previously the current message.
1427 The parent message of the current message,
1428 that is the message with the Message-ID given in the
1430 field or the last entry of the
1432 field of the current message.
1434 The next previous undeleted message,
1435 or the next previous deleted message for the
1438 In sorted/threaded mode,
1439 the next previous such message in the sorted/threaded order.
1441 The next undeleted message,
1442 or the next deleted message for the
1445 In sorted/threaded mode,
1446 the next such message in the sorted/threaded order.
1448 The first undeleted message,
1449 or the first deleted message for the
1452 In sorted/threaded mode,
1453 the first such message in the sorted/threaded order.
1456 In sorted/threaded mode,
1457 the last message in the sorted/threaded order.
1461 selects the message addressed with
1465 is any other message specification,
1466 and all messages from the thread that begins at it.
1467 Otherwise it is identical to
1472 the thread beginning with the current message is selected.
1477 All messages that were included in the message list for the previous
1480 .It Ar / Ns Ar string
1481 All messages that contain
1483 in the subject field (case ignored).
1490 the string from the previous specification of that type is used again.
1492 .It Xo Op Ar @ Ns Ar name-list Ns
1495 All messages that contain the given case-insensitive search
1497 ession; if the \*(OPal regular expression (see
1499 support is available
1501 will be interpreted as one if any of the
1503 regular expression characters is seen.
1505 .Ar @ Ns Ar name-list
1506 part is missing, the search is restricted to the subject field body,
1509 specifies a comma-separated list of header fields to search, as in
1511 .Dl '@to,from,cc@Someone i ought to know'
1513 In order to search for a string that includes a
1515 (commercial at) character the
1517 is effectively non-optional, but may be given as the empty string.
1518 Some special header fields may be abbreviated:
1532 respectively and case-insensitively.
1537 can be used to search in (all of) the header(s) of the message, and the
1546 can be used to perform full text searches \(en whereas the former
1547 searches only the body, the latter also searches the message header.
1549 This message specification performs full text comparison, but even with
1550 regular expression support it is almost impossible to write a search
1551 expression that savely matches only a specific address domain.
1552 To request that the content of the header is treated as a list of
1553 addresses, and to strip those down to the plain email address which the
1554 search expression is to be matched against, prefix the header name
1555 (abbreviation) with a tilde
1558 .Dl '@~f@@a\e.safe\e.domain\e.match$'
1562 .Dq any substring matches
1565 header, which will match addresses (too) even if
1567 is set (and POSIX says
1568 .Dq any address as shown in a header summary shall be matchable in this form ) ;
1571 variable is set, only the local part of the address is evaluated
1572 for the comparison, not ignoring case, and the setting of
1574 is completely ignored.
1575 For finer control and match boundaries use the
1577 search expression; the \*(OPal IMAP-style
1579 expression can also be used if substring matches are desired.
1583 \*(OP IMAP-style SEARCH expressions may also be used.
1584 This addressing mode is available with all types of folders;
1585 \*(UA will perform the search locally as necessary.
1586 Strings must be enclosed by double quotes
1588 in their entirety if they contain white space or parentheses;
1589 within the quotes, only backslash
1591 is recognized as an escape character.
1592 All string searches are case-insensitive.
1593 When the description indicates that the
1595 representation of an address field is used,
1596 this means that the search string is checked against both a list
1599 .Bd -literal -offset indent
1600 (\*qname\*q \*qsource\*q \*qlocal-part\*q \*qdomain-part\*q)
1605 and the addresses without real names from the respective header field.
1606 These search expressions can be nested using parentheses, see below for
1610 .Bl -tag -compact -width ".It Ar _n_u"
1611 .It Ar ( criterion )
1612 All messages that satisfy the given
1614 .It Ar ( criterion1 criterion2 ... criterionN )
1615 All messages that satisfy all of the given criteria.
1617 .It Ar ( or criterion1 criterion2 )
1618 All messages that satisfy either
1623 To connect more than two criteria using
1625 specifications have to be nested using additional parentheses,
1627 .Ql (or a (or b c)) ,
1631 .Ql ((a or b) and c) .
1634 operation of independent criteria on the lowest nesting level,
1635 it is possible to achieve similar effects by using three separate
1639 .It Ar ( not criterion )
1640 All messages that do not satisfy
1642 .It Ar ( bcc \*q Ns Ar string Ns Ar \*q )
1643 All messages that contain
1645 in the envelope representation of the
1648 .It Ar ( cc \*q Ns Ar string Ns Ar \*q )
1649 All messages that contain
1651 in the envelope representation of the
1654 .It Ar ( from \*q Ns Ar string Ns Ar \*q )
1655 All messages that contain
1657 in the envelope representation of the
1660 .It Ar ( subject \*q Ns Ar string Ns Ar \*q )
1661 All messages that contain
1666 .It Ar ( to \*q Ns Ar string Ns Ar \*q )
1667 All messages that contain
1669 in the envelope representation of the
1672 .It Ar ( header name \*q Ns Ar string Ns Ar \*q )
1673 All messages that contain
1678 .It Ar ( body \*q Ns Ar string Ns Ar \*q )
1679 All messages that contain
1682 .It Ar ( text \*q Ns Ar string Ns Ar \*q )
1683 All messages that contain
1685 in their header or body.
1686 .It Ar ( larger size )
1687 All messages that are larger than
1690 .It Ar ( smaller size )
1691 All messages that are smaller than
1695 .It Ar ( before date )
1696 All messages that were received before
1698 which must be in the form
1702 denotes the day of the month as one or two digits,
1704 is the name of the month \(en one of
1705 .Ql Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ,
1708 is the year as four digits, e.g.,
1712 All messages that were received on the specified date.
1713 .It Ar ( since date )
1714 All messages that were received since the specified date.
1715 .It Ar ( sentbefore date )
1716 All messages that were sent on the specified date.
1717 .It Ar ( senton date )
1718 All messages that were sent on the specified date.
1719 .It Ar ( sentsince date )
1720 All messages that were sent since the specified date.
1722 The same criterion as for the previous search.
1723 This specification cannot be used as part of another criterion.
1724 If the previous command line contained more than one independent
1725 criterion then the last of those criteria is used.
1729 .\" .Ss "On URL syntax and credential lookup" {{{
1730 .Ss "On URL syntax and credential lookup"
1732 \*(IN For accessing protocol-specific resources, like POP3 mailboxes,
1733 usage of compact and standardized Uniform Resource Locators
1734 (URL, RFC 1738) has become omnipresent.
1735 \*(UA expects and understands URLs in the following form;
1738 denote optional parts, optional either because there also exist other
1739 ways to define the information in question or because support of the
1740 part is protocol-specific \(en e.g.,
1742 is used by the IMAP protocol but not by POP3.
1745 .Dl PROTOCOL://[USER[:PASSWORD]@]server[:port][/path]
1752 are specified as part of an URL they must be given in URL percent
1753 encoded (RFC 3986) form \(en the command
1755 can be used to perform the encoding and show the encoded value.
1756 (This doesn't really conform to any standard, but for one it isn't
1757 used for any data exchange over the internet, and second it's easier for
1758 users to simply call
1760 on a string and use that instead of having to deal with several
1761 different standards.)
1762 On the other hand, values given in variables are expected not to be URL
1766 Many variable options of \*(UA exist in multiple versions, called
1767 variable chains for the rest of this document: the plain
1772 .Ql variable-USER@HOST .
1779 had been specified in the respective URL, otherwise it refers to the plain
1785 that had been found when doing the user chain lookup as is described
1788 will never be in URL percent encoded form, wether it came from an URL or not.
1791 For example, wether an hypothetical URL
1792 .Ql smtp://hey%3Ayou@our.house
1793 had been given that includes a user, or wether the URL was
1794 .Ql smtp://our.house
1795 and the user had been found differently, to lookup the variable chain
1796 .Va smtp-use-starttls
1797 \*(UA first looks for wether
1798 .Ql smtp-\:use-\:starttls-\:hey:you@our.house
1799 is defined, then wether
1800 .Ql smtp-\:use-\:starttls-\:our.house
1801 exists before finally ending up looking at the plain variable itself.
1804 \*(UA obeys the following logic scheme when dealing with the
1805 necessary credential informations of an account:
1811 has been given in the URL the variables
1815 are looked up; if no such variable(s) can be found then \*(UA will,
1816 when enforced by the \*(OPal variables
1817 .Va netrc-lookup-HOST
1824 specific entry which provides a
1826 name: this lookup will only succeed if unambiguous (one possible matching
1830 If there is still no
1832 then \*(UA will fall back to the user who is supposed to run \*(UA:
1833 either the name that has been given with the
1835 command line option (or, equivalently, but with less precedence, the
1836 environment variable
1841 The identity of this user has been fixated during \*(UA startup and is
1842 known to be a valid user on the current host.
1845 Authentication: unless otherwise noted this will lookup the
1846 .Va PROTOCOL-auth-USER@HOST , PROTOCOL-auth-HOST , PROTOCOL-auth
1847 variable chain, falling back to a protocol-specific default should this
1853 has been given in the URL \(en it should be noted once that specifying
1854 the password in the URL is only syntactic sugar for the user, it'll
1855 never be part of an URL that \*(UA uses itself \(en, then if the
1857 has been found through the \*(OPal
1859 file lookup then that may have already provided the password, too.
1860 Otherwise the variable chain
1861 .Va password-USER@HOST , password-HOST , password
1864 \*(OP Then if any of the variables of the chain
1865 .Va agent-shell-lookup-USER@HOST , agent-shell-lookup-HOST , \
1867 is set the shell command specified therein is run and the output (less
1868 newline characters) will be used as the password.
1869 It is perfectly valid for such an agent to simply not return any data,
1870 in which case the password lookup is continued somewhere else;
1871 Any command failure is treated as a hard error, however.
1873 The next variable chain that is inspected is the \*(OPal
1874 .Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup ,
1875 but this time looking only for the password (multiple user accounts
1876 for a single machine may exist as well as a fallback entry without
1877 user but with a password).
1879 If at that point there is still no password available, but the
1880 (protocols') chosen authentication type requires a password, then in
1881 interactive mode the user will be prompted on the terminal.
1886 S/MIME verification works relative to the values found in the
1890 header field(s), which means that the values of
1891 .Va smime-sign , smime-sign-cert , smime-sign-include-certs
1893 .Va smime-sign-message-digest
1894 will not be looked up using the
1898 chains from above but instead use the corresponding values from the
1899 message that is being worked on.
1900 In unusual cases multiple and different
1904 combinations may therefore be involved \(en on the other hand those
1905 unusual cases become possible.
1906 The usual case is as short as:
1909 .Dl set smtp=smtp://USER:PASS@HOST smtp-use-starttls \e
1910 .Dl \ \ \ \ smime-sign smime-sign-cert=+smime.pair
1915 contains complete example configurations.
1918 .\" .Ss "Command line editor" {{{
1919 .Ss "Command line editor"
1921 \*(OP \*(UA can be configured to support a command line editor and
1922 command history lists which are saved in between sessions.
1923 One may link against fully-fledged external libraries
1924 .Pf ( Xr readline 6 ,
1926 ) or use \*(UA's own command line editor NCL (Nail-Command-Line)
1927 instead, which should work in all environments which comply to the
1928 ISO C standard (ISO/IEC 9899:1990/Amendment 1:1995).
1929 When an external library is used, interactive behaviour of \*(UA relies
1930 on that library and may not correspond one-to-one to what is described
1934 Regardless of the actually used command line editor
1936 entries will be created for lines entered in command mode only, and
1937 creation of such an entry can be forcefully suppressed by starting the
1938 line with a space character.
1941 handling is by itself an optional feature and may therefore not be
1943 For more information see the documentation of the options
1946 .Va history-gabby-persist ,
1947 .Va line-editor-disable ,
1953 The builtin \*(UA command line editor supports the following operations;
1956 stands for the combination of the
1958 key plus the mentioned character, e.g.,
1961 .Dq hold down control key and press the A key :
1964 .Bl -tag -compact -width "Ql _M"
1966 Go to the start of the line.
1968 Move the cursor backward one character.
1970 Forward delete the character under the cursor;
1971 quits \*(UA if used on the empty line unless the
1975 Go to the end of the line.
1977 Move the cursor forward one character.
1980 Cancel current operation, full reset.
1981 If there is an active history search or tabulator expansion then this
1982 command will first reset that, reverting to the former line content;
1983 thus a second reset is needed for a full reset in this case.
1984 In all cases \*(UA will reset a possibly used multibyte character input
1990 backward delete one character.
1994 .Dq horizontal tabulator :
1995 try to expand the word before the cursor.
1997 .Dq tabulator-completion
1998 as is known from the
2000 but really means the usual \*(UA expansion, as documented for
2002 yet it involves shell expansion as a last step, too.)
2007 complete this line of input.
2009 Delete all characters from the cursor to the end of the line.
2013 \*(OP Go to the next history entry.
2018 \*(OP Go to the previous history entry.
2020 \*(OP Complete the current line from (the remaining older) history entries.
2027 Delete the characters from the one preceding the cursor to the preceding
2030 Move the cursor forward one word boundary.
2032 Move the cursor backward one word boundary.
2036 If problems with commands that are based upon rightwise movement are
2037 encountered, adjustments of the option
2038 .Va line-editor-cursor-right
2039 may solve the problem, as documented for it.
2042 If the terminal produces key sequences which are compatible with
2044 then the left and right cursor keys will map to
2048 respectively, the up and down cursor keys will map to
2052 and the Home/End/PgUp/PgDown keys will call the
2054 command with the respective arguments
2060 (i.e., perform scrolling through the header summary list).
2063 .\" .Ss "Coloured message display" {{{
2064 .Ss "Coloured message display"
2066 \*(OP \*(UA can be configured to support coloured message display,
2067 realized by emitting ANSI colour escape sequences.
2068 Colours are only used when the
2070 environment variable is set and either the terminal type can be found in
2072 or its name includes the string
2076 On top of that the binary option
2078 defines wether these colour sequences are also generated when the output
2079 of a command needs to go through the
2083 ) \(en this is not enabled by default because different pager programs
2084 need different command line switches or other configuration in order to
2085 support those colour sequences, please see the option for more details.
2088 To forcefully disable all colour support, set
2089 .Va colour-disable .
2092 Colours can be configured through font attributes
2113 Multiple specifications can be joined in a comma separated list, as in
2116 .Dl set colour-msginfo="ft=bold,fg=magenta,bg=cyan"
2119 Options to be set are
2120 .Va colour-msginfo ,
2121 .Va colour-partinfo ,
2125 .Va colour-uheader ,
2127 .Va colour-user-headers ,
2128 which is a list of headers to be colourized via
2130 instead of the default
2133 .\" }}} (DESCRIPTION)
2136 .\" .Sh COMMANDS {{{
2139 Each command is typed on a line by itself,
2140 and may take arguments following the command word.
2141 The command need not be typed in its entirety \(en
2142 the first command which matches the typed prefix is used.
2145 prints a sorted list of available commands, and the command
2149 when given an argument, will show a documentation string for the
2152 documentation strings are however \*(OPal.)
2155 For commands which take message lists as arguments, the next message
2156 forward that satisfies the command's requirements will be used shall no
2157 explicit message list have been passed.
2158 If there are no messages forward of the current message,
2159 the search proceeds backwards,
2160 and if there are no good messages at all,
2162 .Dq no applicable messages
2163 and aborts the command.
2164 The arguments to commands can be quoted, using the following methods:
2167 .Bl -bullet -compact -offset indent
2169 An argument can be enclosed between paired double-quotes
2174 any white space, shell word expansion, or backslash characters (except
2175 as described next) within the quotes are treated literally as part of
2177 A double-quote will be treated literally within single-quotes and vice
2179 Inside such a quoted string the actually used quote character can be
2180 used nonetheless by escaping it with a backslash
2186 An argument that is not enclosed in quotes, as above, can usually still
2187 contain space characters if those spaces are backslash-escaped.
2190 A backslash outside of the enclosing quotes is discarded
2191 and the following character is treated literally as part of the argument.
2194 An unquoted backslash at the end of a command line is discarded and the
2195 next line continues the command.
2199 Filenames, where expected, are subsequently subjected to the following
2200 transformations, in sequence:
2203 .Bl -bullet -compact -offset indent
2205 If the filename begins with an unquoted plus sign, and the
2207 variable is defined,
2208 the plus sign will be replaced by the value of the
2210 variable followed by a slash.
2213 variable is unset or is set to null, the filename will be unchanged.
2216 Shell word expansions are applied to the filename.
2217 .\" TODO shell word expansion shell expand fexpand FEXP_NSHELL
2218 .Sy Compatibility note:
2219 on the long run support for complete shell word expansion will be
2220 replaced by an internally implemented restricted expansion mechanism in
2221 order to circumvent possible security impacts through shell expansion.
2222 Expect that a growing number of program parts only support this
2225 Meta expansions are applied to the filename: leading tilde characters
2227 will be replaced by the expansion of
2229 and any occurrence of
2233 will be replaced by the expansion of the variable, if possible;
2234 \*(UA internal as well as environmental (shell) variables can be
2235 accessed through this mechanism.
2236 In order to include a raw
2238 character precede it with a backslash
2240 to include a backslash double it.
2241 If more than a single pathname results from this expansion and the
2242 command is expecting one file, an error results.
2244 Note that in interactive display context, in order to allow simple
2245 value acceptance (typing
2247 backslash quoting is performed automatically as necessary, e.g., a file
2248 .Ql diet\e is \ecurd.txt
2249 will be displayed as
2250 .Ql diet\e\e is \e\ecurd.txt .
2254 The following commands are available:
2256 .Bl -tag -width ".Ic _ccount"
2259 The comment-command causes the entire line to be ignored.
2261 this really is a normal command which' purpose is to discard its
2264 indicating special character, which means that, e.g., trailing comments
2265 on a line are not possible.
2269 Interprets the remainder of the word as a macro name and passes it
2274 is a shorter synonym for
2275 .Ql call Ar mymacro .
2279 Print out the preceding message.
2280 If given a numeric argument n,
2281 goes to the n'th previous message and prints it.
2285 Show the current message number (the
2290 Prints a brief summary of commands.
2291 \*(OP Given an argument a synopsis for the command in question is
2293 commands can be abbreviated in general and this command can be used
2294 to see the full expansion of an abbreviation including the synopsis,
2300 and see how the display changes.
2308 ) command which follows.
2318 (ac) Creates, selects or lists (an) account(s).
2319 An account is a group of commands and variable settings which together
2320 usually arrange the environment for the purpose of creating a system login.
2321 Without any argument a listing of all defined accounts and their content
2323 A specific account can be activated by giving solely its name, resulting
2324 in the system mailbox or inbox of that account to be activated as via an
2325 explicit use of the command
2327 The two argument form is identical to defining a macro as via
2330 .Bd -literal -offset indent
2332 set folder=imaps://mylogin@imap.myisp.example
2334 set from="myname@myisp.example (My Name)"
2335 set smtp=smtp://mylogin@smtp.myisp.example
2339 creates an account named
2341 which can later be selected by specifying
2345 (case-insensitive) always exists.
2347 can be used to localize account settings \(en different to normal macros
2348 the settings will be reverted once the account is switched off.
2349 Accounts can be deleted via
2354 (a) With no arguments, prints out all currently-defined aliases.
2355 With one argument, prints out that alias.
2356 With more than one argument,
2357 creates a new alias or appends to an existing one.
2359 can be used to delete aliases.
2363 (alt) Manage a list of alternate addresses / names of the active user,
2364 members of which will be removed from recipient lists when replying to
2367 variable is not set).
2368 If arguments are given the set of alternate names is replaced by them,
2369 without arguments the current set is displayed.
2373 Takes a message list and marks each message as having been answered.
2374 This mark has no technical meaning in the mail system;
2375 it just causes messages to be marked in the header summary,
2376 and makes them specially addressable.
2380 \*(OP Only applicable to cached IMAP mailboxes;
2381 takes a message list and reads the specified messages into the IMAP
2386 Calls a macro that has been created via
2391 (ch) Change the working directory to
2393 or the given argument.
2399 \*(OP Only applicable to S/MIME signed messages.
2400 Takes a message list and a file name and saves the certificates
2401 contained within the message signatures to the named file in both
2402 human-readable and PEM format.
2403 The certificates can later be used to send encrypted messages to the
2404 respective message senders by setting
2405 .Va smime-encrypt-USER@HOST
2410 (ch) Change the working directory to
2412 or the given argument.
2418 Only applicable to threaded mode.
2419 Takes a message list and makes all replies to these messages invisible
2420 in header summaries, unless they are in state
2425 \*(OP If operating in disconnected mode on an IMAP mailbox,
2426 switch to online mode and connect to the mail server while retaining
2428 See the description of the
2430 variable for more information.
2434 (C) Copy messages to files whose names are derived from the author of
2435 the respective message and don't mark them as being saved;
2436 otherwise identical to
2441 (c) Copy messages to the named file and don't mark them as being saved;
2442 otherwise identical to
2447 Print the current working directory.
2451 \*(OP For unencrypted messages this command is identical to
2453 Encrypted messages are first decrypted, if possible, and then copied.
2457 \*(OP For unencrypted messages this command is identical to
2459 Encrypted messages are first decrypted, if possible, and then copied.
2463 Without arguments the current list of macros, including their content,
2464 is printed, but otherwise a macro is defined.
2465 A macro definition is a sequence of commands in the following form:
2466 .Bd -literal -offset indent
2475 A defined macro can be invoked explicitly by using the
2479 commands, or implicitly by setting the
2482 .Va folder-hook-FOLDER
2484 Note that interpretation of
2486 depends on how (i.e.,
2488 normal macro, folder hook, account switch) the macro is invoked.
2489 Macros can be deleted via
2494 (d) Marks the given message list as
2496 Deleted messages will neither be saved in
2498 nor will they be available for most other commands.
2509 \*(OP (disco) If operating in online mode on an IMAP mailbox,
2510 switch to disconnected mode while retaining the mailbox status.
2511 See the description of the
2514 A list of messages may optionally be given as argument;
2515 the respective messages are then read into the cache before the
2516 connection is closed.
2517 Thus `disco *' makes the entire mailbox available for disconnected use.
2522 Deletes the current message and prints the next message.
2523 If there is no next message, \*(UA says
2528 Takes a message list and marks each given message as a draft.
2529 This mark has no technical meaning in the mail system;
2530 it just causes messages to be marked in the header summary,
2531 and makes them specially addressable.
2535 (ec) Echoes its arguments,
2536 resolving special names as documented for the command
2538 The escape sequences
2550 are interpreted just as they are by
2552 (proper quoting provided).
2556 (e) Point the text editor (as defined in
2558 at each message from the given list in turn.
2559 Modified contents are discarded unless the
2566 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
2567 conditional \(em if the condition of a preceeding
2569 was false, check the following condition and execute the following block
2570 if it evaluates true.
2575 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
2576 conditional \(em if none of the conditions of the preceeding
2580 commands was true, the
2586 (en) Marks the end of an
2587 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
2588 conditional execution block.
2592 \*(OP Since \*(UA uses the console as a user interface it can happen
2593 that messages scroll by too fast to become recognized.
2594 Optionally an error message ring queue is available which stores
2595 duplicates of any error message and notifies the user in interactive
2596 sessions whenever a new error has occurred.
2597 The queue is finite: if its maximum size is reached any new message
2598 replaces the eldest.
2601 can be used to manage this message queue: if given
2603 or no argument the queue will be displayed and cleared,
2605 will only clear all messages from the queue.
2609 (ex or x) Exit from \*(UA without changing the active mailbox and skip
2610 any saving of messages in
2612 as well as a possibly tracked command line editor history file.
2616 Print the list of features that have been compiled into \*(UA.
2622 but open the mailbox readonly.
2626 (fi) The file command switches to a new mailbox.
2627 Without arguments it prints the complete state of the current mailbox.
2628 If an argument is given, it will write out changes (such as deletions)
2629 the user has made and open a new mailbox.
2630 Some special conventions are recognized for the
2634 .Bl -tag -compact -offset indent -width ".Ar %:__lespec"
2636 (number sign) means the previous file,
2638 (percent sign) means the invoking user's system mailbox
2643 means the system mailbox of
2645 (and never the value of
2647 regardless of its actual setting),
2649 (ampersand) means the invoking user's
2659 expands to the same value as
2661 but the file is handled as a system mailbox by, e.g., the
2665 commands, meaning that messages that have been read in the current
2666 session will be moved to the
2668 mailbox instead of simply being flagged as read.
2671 If the name matches one of the strings defined with the command
2673 it is replaced by its long form and expanded.
2674 If the name ends with
2679 it is treated as being compressed with
2684 respectively, and transparently handled through an intermediate
2685 (un)compression step (using a temporary file) with the according
2686 facility, sufficient support provided.
2687 Likewise, if the named file doesn't exist, but a file with one of the
2688 mentioned compression extensions does, then the name is automatically
2689 expanded and the compressed file is used.
2691 Otherwise, if the name ends with an extension for which
2692 .Va file-hook-load-EXTENSION
2694 .Va file-hook-save-EXTENSION
2695 variables are set, then the given hooks will be used to load and save
2697 and \*(UA will work with an intermediate temporary file.
2699 MBOX files (flat file-based mailboxes) are generally locked during file
2700 operations in order to avoid inconsistencies against concurrent
2702 Mailbox files which \*(UA treats as system mailboxes will also be
2703 protected by so-called dotlock files, the traditional way of mail spool
2704 file locking: for any file
2708 will be created for the duration of the synchronization \(em
2709 as necessary a privilege-separated dotlock child process will be used
2710 to accommodate for necessary privilege adjustments in order to create
2711 the dotlock file in the same directory
2712 and with the same user and group identities as the file of interest.
2715 for fine-tuning the handling of MBOX files.
2719 refers to a directory with the subdirectories
2724 then it is treated as a folder in
2729 .Dl \*(IN protocol://[user[:password]@]host[:port][/path]
2730 .Dl \*(OU protocol://[user@]host[:port][/path]
2732 is taken as an Internet mailbox specification.
2733 The \*(OPally supported protocols are
2737 (POP3 with SSL/TLS encrypted transport).
2740 part is valid only for IMAP; there it defaults to
2742 Also see the section
2743 .Sx "On URL syntax and credential lookup" .
2747 contains special characters, in particular
2751 they must be escaped in URL notation \(en the command
2753 can be used to show the necessary conversion.
2754 The optional `path' part applies to IMAP only;
2755 if it is omitted, the default `INBOX' is used.
2757 If \*(UA is connected to an IMAP server,
2758 a name of the form `@mailbox' refers to the `mailbox' on that server,
2759 but otherwise a `@' prefix has no special meaning.
2763 Takes a message list and marks the messages as
2765 ged for urgent/special attention.
2766 This mark has no technical meaning in the mail system;
2767 it just causes messages to be highlighted in the header summary,
2768 and makes them specially addressable.
2777 With no arguments, list the names of the folders in the folder directory.
2778 With an existing folder as an argument,
2779 lists the names of folders below the named folder;
2780 e.\|g. the command `folders @' lists the folders on the base level of
2781 the current IMAP server.
2782 See also the variable
2783 .Va imap-list-depth .
2789 but saves the message in a file named after the local part of the first
2790 recipient's address (instead of in
2797 but saves the message in a file named after the local part of the first
2798 recipient's address (instead of in
2805 but responds to all recipients regardless of the
2810 .It Ic followupsender
2813 but responds to the sender only regardless of the
2829 (f) Takes a list of messages and prints their message headers
2830 (which qualifies this command as \*(UAs search facility).
2836 but saves the message in a file named after the local part of the
2837 recipient's address (instead of in
2842 Takes a message and the address of a recipient
2843 and forwards the message to him.
2844 The text of the original message is included in the new one,
2845 with the value of the
2847 variable printed before.
2852 commands specify which header fields are included in the new message.
2853 Only the first part of a multipart message is included unless the
2854 .Va forward-as-attachment
2858 is set recipient addresses will be stripped from comments, names etc.
2862 Specifies which header fields are to be ignored with the command
2864 This command has no effect when the
2865 .Va forward-as-attachment
2870 Specifies which header fields are to be retained with the command
2875 This command has no effect when the
2876 .Va forward-as-attachment
2881 Define or list command aliases, so-called ghosts.
2882 Without arguments a list of all currently known aliases is printed.
2883 With one argument the expansion of the given alias is shown.
2884 With two or more arguments a command alias is defined or updated: the
2885 first argument is the name under which the remaining command line should
2886 be accessible, the content of which can be just about anything.
2887 A ghost can be used everywhere a normal command can be used, but always
2888 takes precedence; any arguments that are given to the command alias are
2889 joined onto the alias content, and the resulting string forms the
2890 command line that is, in effect, executed.
2893 .Bd -literal -offset indent
2895 `ghost': no such alias: "xx"
2898 ghost xx "echo hello,"
2907 (h) Show the current group of headers, the size of which depends on
2910 If a message-specification is given the group of headers containing the
2911 first message therein is shown and the message at the top of the screen
2926 the list of history entries;
2929 argument selects and shows the respective history entry \(en
2932 to accept it, and the history entry will become the new history top.
2933 The default mode if no arguments are given is
2940 Takes a message list and marks each message therein to be saved in the
2941 user's system mailbox instead of in
2943 Does not override the
2946 \*(UA deviates from the POSIX standard with this command, because a
2948 command issued after
2950 will display the following message, not the current one.
2955 (i) Part of the nestable
2956 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
2957 conditional execution construct \(em if the given condition is true then
2958 the encapsulated block is executed.
2959 POSIX only supports the conditions
2964 (execute if standard input is a tty), all remaining conditions are
2965 non-portable extensions; note that falsely specified conditions cause
2966 the execution of the entire conditional construct until the
2969 command to be suppressed.
2970 The syntax of the nestable
2972 conditional execution construct requires that each condition and syntax
2973 element is surrounded by whitespace.
2975 .Bd -literal -offset indent
2984 Another condition can be any boolean value (see the section
2986 for booleans) to mark an enwrapped block as
2989 .Dq always execute .
2990 It is possible to check a variable for existence or compare its
2991 expansion against a user given value or another variable via the
2993 .Pf ( Dq variable next )
2994 conditional trigger character.
2995 The available comparison operators are
2999 (less than or equal to),
3005 (greater than or equal to),
3009 (is substring of) and
3011 (is not substring of).
3012 The values of the left and right hand side are treated as strings and
3013 are compared 8-bit byte-wise, ignoring case according to the rules of
3014 the US-ASCII encoding (therefore, dependend on the active locale,
3015 possibly producing false results for strings in the locale encoding).
3016 Except for the substring checks the comparison will instead be performed
3017 arithmetically if both, the user given value as well as the variable
3018 content, can be parsed as numbers (integers).
3019 An unset variable is treated as the empty string.
3022 When the \*(OPal regular expression support is available, the additional
3028 They treat the right hand side as a regular expression that is matched
3029 case-insensitively and according to the active
3031 locale, meaning that strings in the locale encoding should be matched
3035 Conditions can be joined via AND-OR lists (where the AND operator is
3037 and the OR operator is
3039 which have equal precedence and will be evaluated with left
3040 associativity, thus using the same syntax that is known for the
3042 It is also possible to form groups of conditions and lists by enclosing
3043 them in pairs of brackets
3044 .Ql [\ \&.\&.\&.\ ] ,
3045 which may be interlocked within each other, and also be joined via
3049 The results of individual conditions and entire groups may be modified
3050 via unary operators: the unary operator
3052 will reverse the result.
3054 .Bd -literal -offset indent
3058 if $ttycharset == "UTF-8"
3059 echo *ttycharset* is set to UTF-8, case-insensitively
3063 echo These two variables are equal
3065 if $version-major >= 15
3066 echo Running a new version..
3067 if $features =@ "regex"
3068 if $TERM =~ "^xterm\&.*"
3069 echo ..in an X terminal
3072 if [ [ true ] && [ [ $debug ] || [ $verbose ] ] ]
3075 if true && $debug || $verbose
3076 echo Left associativity, as is known from the shell
3078 if ! ! true && ! [ ! $debug && ! $verbose ]
3079 echo Unary operator support
3087 Without arguments the list of ignored header fields is printed,
3088 otherwise the given list of header fields is added to the ignore list:
3089 Header fields in the ignore list are not printed on the terminal when
3090 a message is printed.
3091 To print a message in its entirety, use the commands
3102 \*(OP Sends command strings directly to the current IMAP server.
3103 \*(UA operates always in IMAP `selected state' on the current mailbox;
3104 commands that change this will produce undesirable results and should be
3106 Useful IMAP commands are:
3107 .Bl -tag -offset indent -width ".Ic getquotearoot"
3109 Takes the name of an IMAP mailbox as an argument and creates it.
3111 (RFC 2087) Takes the name of an IMAP mailbox as an argument
3112 and prints the quotas that apply to the mailbox.
3113 Not all IMAP servers support this command.
3115 (RFC 2342) Takes no arguments and prints the Personal Namespaces,
3116 the Other User's Namespaces and the Shared Namespaces.
3117 Each namespace type is printed in parentheses;
3118 if there are multiple namespaces of the same type,
3119 inner parentheses separate them.
3120 For each namespace a prefix and a hierarchy separator is listed.
3121 Not all IMAP servers support this command.
3131 Prints the names of all available commands, alphabetically sorted.
3135 This command can be used to localize changes to variables, meaning that
3136 their state will be reverted to the former one once the covered scope
3138 It can only be used inside of macro definition blocks introduced by
3142 and is interpreted as a boolean (see
3143 .Sx "Value options" ) ;
3146 of an account is left once it is switched off again.
3147 .Bd -literal -offset indent
3148 define temporary_settings {
3163 enables change localization and calls
3165 which explicitly resets localization, then any value changes within
3167 will still be reverted by
3172 Reply to messages that come in via known
3175 .Pf ( Ic mlsubscribe )
3176 mailing lists, or pretend to do so (see
3177 .Sx "Mailing lists" ) :
3180 functionality this will actively resort and even remove message
3181 recipients in order to generate a message that is supposed to be send to
3183 For example it will also implicitly generate a
3184 .Ql Mail-Followup-To:
3185 header if that seems useful, regardless of the setting of the variable
3192 but saves the message in a file named after the local part of the first
3193 recipient's address (instead of in
3198 (m) Takes a (list of) recipient address(es) as (an) argument(s),
3199 or asks on standard input if none were given;
3200 then collects the remaining mail content and sends it out.
3204 (mb) The given message list is to be sent to
3206 when \*(UA is quit; this is the default action unless the
3209 \*(ID This command can only be used in a system mailbox (see
3214 Without any arguments the content of the MIME type cache will displayed.
3215 Otherwise each argument defines a complete MIME type specification of
3216 a type that shall be added (prepended) to the cache.
3217 In any event MIME type sources are loaded first as necessary \(en
3218 .Va mimetypes-load-control
3219 can be used to fine-tune which sources are actually loaded.
3220 Refer to the section on
3221 .Sx "The mime.types files"
3222 for more on MIME type specifications and this topic in general.
3223 MIME type unregistration and cache resets can be triggered with
3228 Without arguments the list of all currently defined mailing lists
3229 (and their attributes, if any) is printed.
3230 Otherwise all given arguments (which need not be quoted except for
3231 whitespace) will be added and henceforth be recognized as mailing lists.
3232 Mailing lists may be removed via the command
3235 If the \*(OPal regular expression support is available then mailing
3236 lists may also be specified as regular expressions (see
3242 Without arguments the list of all currently defined mailing lists which
3243 have a subscription attribute is printed.
3244 Otherwise this attribute will be set for all given mailing lists,
3245 newly creating them as necessary (as via
3247 Subscription attributes may be removed via the command
3256 but moves the messages to a file named after the local part of the
3257 sender address of the first message (instead of in
3264 but marks the messages for deletion if they were transferred
3271 but also prints ignored header fields and all MIME parts.
3279 on the given messages, even in non-interactive mode and as long as the
3280 standard output is a terminal.
3292 cache, loading the file first as necessary in the former case.
3293 Note that \*(UA will try to read the file only once, use
3294 .Ql Ic netrc Ns \:\0\:clear
3295 to unlock the next attempt.
3299 .Sx "On URL syntax and credential lookup" ;
3301 .Sx "The .netrc file"
3302 documents the file format in detail.
3306 Checks for new mail in the current folder without committing any changes
3308 If new mail is present, a message is printed.
3312 the headers of each new message are also printed.
3320 Goes to the next message in sequence and types it.
3321 With an argument list, types the next matching message.
3335 If the current folder is accessed via a network connection, a
3337 command is sent, otherwise no operation is performed.
3343 but also prints ignored header fields and all MIME parts.
3351 on the given messages, even in non-interactive mode and as long as the
3352 standard output is a terminal.
3360 but also pipes ignored header fields and all parts of MIME
3361 .Ql multipart/alternative
3366 (pi) Takes a message list and a shell command
3367 and pipes the messages through the command.
3368 Without an argument the current message is piped through the command
3375 every message is followed by a formfeed character.
3386 but also prints out ignored header fields and all parts of MIME
3387 .Ql multipart/alternative
3397 (p) Takes a message list and types out each message on the user's
3399 For MIME multipart messages, all parts with a content type of
3403 are shown, the other are hidden except for their headers.
3404 Messages are decrypted and converted to the terminal character set
3409 (q) Terminates the session, saving all undeleted, unsaved messages in
3412 preserving all messages marked with
3416 or never referenced in the system mailbox,
3417 and removing all other messages from the system mailbox.
3418 If new mail has arrived during the session,
3420 .Dq You have new mail
3422 If given while editing a mailbox file with the command line flag
3424 then the edit file is rewritten.
3425 A return to the shell is effected,
3426 unless the rewrite of edit file fails,
3427 in which case the user can escape with the exit command.
3441 Removes the named folders.
3442 The user is asked for confirmation in interactive mode.
3446 Takes the name of an existing folder
3447 and the name for the new folder
3448 and renames the first to the second one.
3449 Both folders must be of the same type
3450 and must be located on the current server for IMAP.
3454 (R) Reply to originator.
3455 Does not reply to other recipients of the original message.
3457 will exchange this command with
3461 is set the recipient address will be stripped from comments, names etc.
3465 (r) Take a message and group-responds to it by addressing the sender
3468 .Va followup-to-honour ,
3471 .Va recipients-in-cc
3472 influence response behaviour.
3475 offers special support for replying to mailing lists.
3478 is set recipient addresses will be stripped from comments, names etc.
3491 but initiates a group-reply regardless of the value of
3498 but responds to the sender only regardless of the value of
3505 but does not add any header lines.
3506 This is not a way to hide the sender's identity,
3507 but useful for sending a message again to the same recipients.
3511 Takes a list of messages and a user name
3512 and sends each message to the named user.
3514 and related header fields are prepended to the new copy of the message.
3532 .It Ic respondsender
3538 (ret) Without arguments the list of retained header fields is printed,
3539 otherwise the given list of header fields is added to the retain list:
3540 Header fields in the retain list are shown on the terminal when
3541 a message is printed, all other header fields are suppressed.
3542 To print a message in its entirety, use the commands
3551 takes precedence over the mentioned.
3557 but saves the messages in a file named after the local part of the
3558 sender of the first message instead of (in
3560 and) taking a filename argument.
3564 (s) Takes a message list and a filename and appends each message in turn
3565 to the end of the file.
3566 If no filename is given, the
3569 The filename in quotes, followed by the generated character count
3570 is echoed on the user's terminal.
3571 If editing a system mailbox the messages are marked for deletion.
3572 Compressed files and IMAP mailboxes are handled as described for the
3574 command line option above.
3591 Header fields thus marked are filtered out when saving a message by
3593 or when automatically saving to
3595 This command should only be applied to header fields that do not contain
3596 information needed to decode the message,
3597 as MIME content fields do.
3598 If saving messages on an IMAP account ignoring fields makes it
3599 impossible to copy the data directly on the server,
3600 thus operation usually becomes much slower.
3612 Header fields thus marked are the only ones saved with a message when
3615 or when automatically saving to
3620 The use of this command is strongly discouraged since it may strip
3621 header fields that are needed to decode the message correctly.
3625 Takes a message list and marks all messages as having been read.
3629 (se) Without arguments this command prints all options and, for
3630 non-binary options, values that are currently known to \*(UA.
3631 Setting any of the options
3635 changes the output format to BSD style, otherwise a properly quoted
3636 listing is produced.
3641 has been set twice then the listing is modified to mark out assembled
3644 Otherwise modifies (set and unsets) the given options.
3645 Arguments are of the form
3647 (no space before or after
3651 if there is no value.
3652 Quotation marks may be placed around any part of the assignment
3653 statement to quote blanks or tabs, e.g.,
3655 .Dl set indentprefix="->"
3657 If an argument begins with
3661 the effect is the same as invoking the
3663 command with the remaining part of the variable
3664 .Pf ( Ql unset save ) .
3670 except that the options are also exported into the program environment;
3671 since this task requires native host support the command will always
3672 report error if that is not available (but still act like
3675 This operation is a no-op unless all resource files have been loaded.
3681 (sh) Invokes an interactive version of the shell.
3685 Without arguments the list of all currently defined shortcuts is
3687 Otherwise all given arguments (which need not be quoted except for
3688 whitespace) are treated as pairs of shortcuts and their expansions,
3689 creating new or changing already existing shortcuts, as necessary.
3690 Shortcuts may be removed via the command
3692 The expansion strings should be in the syntax that has been described
3701 but performs neither MIME decoding nor decryption, so that the raw
3702 message text is shown.
3706 (si) Print the size in characters of each message of the given
3711 Create a sorted representation of the current folder,
3714 command and the addressing modes such that they refer to messages in the
3716 Message numbers are the same as in regular mode.
3720 a header summary in the new order is also printed.
3721 Possible sorting criteria are:
3723 .Bl -tag -compact -offset indent -width "subject"
3725 Sort the messages by their
3727 field, that is by the time they were sent.
3729 Sort messages by the value of their
3731 field, that is by the address of the sender.
3734 variable is set, the sender's real name (if any) is used.
3736 Sort the messages by their size.
3738 \*(OP Sort the message by their spam score, as has been classified by
3741 Sort the messages by their message status.
3743 Sort the messages by their subject.
3745 Create a threaded display.
3747 Sort messages by the value of their
3749 field, that is by the address of the recipient.
3752 variable is set, the recipient's real name (if any) is used.
3755 If no argument is given,
3756 the current sorting criterion is printed.
3760 (so) The source command reads commands from a file.
3766 is that this command will not generate an error if the given file
3767 argument cannot be opened successfully.
3768 This can matter in, e.g., resource files, since loading of those is
3769 stopped when an error is encountered.
3773 \*(OP Takes a list of messages and clears their
3779 \*(OP Takes a list of messages and causes the
3781 to forget it has ever used them to train its Bayesian filter.
3782 Unless otherwise noted the
3784 flag of the message is inspected to chose wether a message shall be
3792 \*(OP Takes a list of messages and informs the Bayesian filter of the
3796 This also clears the
3798 flag of the messages in question.
3802 \*(OP Takes a list of messages and rates them using the configured
3803 .Va spam-interface ,
3804 without modifying the messages, but setting their
3806 flag as appropriate; because the spam rating headers are lost the rate
3807 will be forgotten once the mailbox is left.
3808 Refer to the manual section
3810 for the complete picture of spam handling in \*(UA.
3814 \*(OP Takes a list of messages and sets their
3820 \*(OP Takes a list of messages and informs the Bayesian filter of the
3826 flag of the messages in question.
3835 Create a threaded representation of the current folder,
3836 i.\|e. indent messages that are replies to other messages in the header
3837 display and change the
3839 command and the addressing modes such that they refer to messages in the
3841 Message numbers are the same as in unthreaded mode.
3845 a header summary in threaded order is also printed.
3849 (to) Takes a message list and prints the top few lines of each.
3850 The number of lines printed is controlled by the variable
3852 and defaults to five.
3856 (tou) Takes a message list and marks the messages for saving in
3858 \*(UA deviates from the POSIX standard with this command,
3861 command will display the following message instead of the current one.
3865 (T) Identical to the
3876 Delete all given accounts.
3877 An error message is printed if a given account is not defined.
3880 will discard all existing accounts.
3884 (una) Takes a list of names defined by alias commands
3885 and discards the remembered groups of users.
3888 will discard all existing aliases.
3892 Takes a message list and marks each message as not having been answered.
3896 Only applicable to threaded mode.
3897 Takes a message list and makes the message and all replies to it visible
3898 in header summaries again.
3899 When a message becomes the current message,
3900 it is automatically made visible.
3901 Also when a message with collapsed replies is printed,
3902 all of these are automatically uncollapsed.
3906 Undefine all given macros.
3907 An error message is printed if a given macro is not defined.
3910 will discard all existing macros.
3914 (u) Takes a message list and marks each message as not being deleted.
3918 Takes a message list and
3924 Takes a message list and marks each message as not being
3929 Removes the header field names from the list of ignored fields for the
3934 will remove all fields.
3938 Removes the header field names from the list of retained fields for the
3943 will remove all fields.
3947 Remove all the given command
3951 will remove all ghosts.
3955 Removes the header field names from the list of ignored fields.
3958 will remove all fields.
3962 Delete all given MIME types, e.g.,
3963 .Ql unmimetype text/plain
3964 will remove all registered specifications for the MIME type
3968 will discard all existing MIME types, just as will
3970 but which also reenables cache initialization via
3971 .Va mimetypes-load-control .
3975 Forget about all the given mailing lists.
3978 will remove all lists.
3983 .It Ic unmlsubscribe
3984 Remove the subscription attribute from all given mailing lists.
3987 will clear the attribute from all lists which have it set.
3998 Takes a message list and marks each message as not having been read.
4002 Removes the header field names from the list of retained fields.
4005 will remove all fields.
4009 Removes the header field names from the list of ignored fields for
4013 will remove all fields.
4017 Removes the header field names from the list of retained fields for
4021 will remove all fields.
4025 (uns) Takes a list of option names and discards their remembered values;
4033 except that the options are also removed from the program environment;
4034 since this task requires native host support the command will always
4035 report error if that is not available (but still act like
4038 This operation is a no-op unless all resource files have been loaded.
4044 Deletes the shortcut names given as arguments.
4047 will remove all shortcuts.
4051 Disable sorted or threaded mode
4057 return to normal message order and,
4061 print a header summary.
4071 Decode the given URL-encoded string arguments and show the results.
4075 URL-encode the given arguments and show the results.
4079 Edit the values of or create the given variable(s) in the
4081 Binary variables cannot be edited.
4085 Show informations about all the given options.
4086 \*(UA knows about a finite set of known builtin variables that are
4087 subdivided further in binary and value variants;
4088 they may have special properties, like
4090 (setting may not be changed) and
4092 meaning that the value is generated on-the-fly as necessary.
4093 Beside those known variables an infinite number of unknown, so-called
4095 variables, which are expected to be able to store values, may exist.
4096 .Bd -literal -offset indent
4098 ? varshow sendwait version-major foo bar
4099 "sendwait": (73) binary: set=1 (ENVIRON=0)
4100 "version-major": (192) value, read-only, virtual:\e
4101 set=1 (ENVIRON=0) value<14>
4102 "foo": (assembled) set=1 (ENVIRON=0) value<bar>
4103 "bar": (assembled) set=0 (ENVIRON=0) value<NULL>
4108 \*(OP Takes a message list and verifies each message.
4109 If a message is not a S/MIME signed message,
4110 verification will fail for it.
4111 The verification process checks if the message was signed using a valid
4113 if the message sender's email address matches one of those contained
4114 within the certificate,
4115 and if the message content has been altered.
4119 (v) Takes a message list and invokes the display editor on each message.
4120 Modified contents are discarded unless the
4126 (w) For conventional messages the body without all headers is written.
4127 The output is decrypted and converted to its native format as necessary.
4128 If the output file exists, the text is appended.
4129 If a message is in MIME multipart format its first part is written to
4130 the specified file as for conventional messages,
4131 and the user is asked for a filename to save each other part.
4132 For convience saving of each part may be skipped by giving an empty value;
4133 the same result can also be achieved by writing it to
4135 For the second and subsequent parts a leading
4137 character causes the part to be piped to the remainder of the user input
4138 interpreted as a shell command;
4139 otherwise the user input is expanded as usually for folders,
4140 e.g., tilde expansion is performed.
4141 In non-interactive mode, only the parts of the multipart message
4142 that have a filename given in the part header are written,
4143 the others are discarded.
4144 The original message is never marked for deletion in the originating
4147 the contents of the destination file are overwritten if the file
4149 No special handling of compressed files is performed.
4158 \*(UA presents message headers in windowfuls as described under the
4161 This command scrolls to the next window of messages.
4162 If an argument is given,
4163 it specifies the window to use.
4164 A number prefixed by
4168 indicates that the window is calculated in relation to the current position.
4169 A number without a prefix specifies an absolute window number,
4172 lets \*(UA scroll to the last window of messages.
4178 but scrolls to the next or previous window that contains at least one
4187 .\" .Sh TILDE ESCAPES {{{
4190 Here is a summary of the tilde escapes,
4191 which are used to perform special functions when composing messages.
4192 Tilde escapes are only recognized at the beginning of lines.
4195 is somewhat of a misnomer since the actual escape character can be
4196 changed by adjusting the option
4199 .Bl -tag -width ".Ic __ filename"
4202 Insert the string of text in the message prefaced by a single
4204 (If the escape character has been changed,
4205 that character must be doubled
4206 in order to send it at the beginning of a line.)
4209 .It Ic ~! Ar command
4210 Execute the indicated shell
4212 then return to the message.
4216 Same effect as typing the end-of-file character.
4219 .It Ic ~: Ar \*(UA-command Ns \0or Ic ~_ Ar \*(UA-command
4220 Execute the given \*(UA command.
4221 Not all commands, however, are allowed.
4225 Write a summary of command escapes.
4228 .It Ic ~< Ar filename
4233 .It Ic ~<! Ar command
4235 is executed using the shell.
4236 Its standard output is inserted into the message.
4239 .It Ic ~@ Op Ar filename...
4240 With no arguments, edit the attachment list interactively.
4241 If an attachment's file name is left empty,
4242 that attachment is deleted from the list.
4243 When the end of the attachment list is reached,
4244 \*(UA will ask for further attachments until an empty name is given.
4245 If a given file name solely consists of the number sign
4247 followed by a valid message number of the currently active mailbox, then
4248 the given message is attached as a MIME
4250 and the rest of this section does not apply.
4252 If character set conversion has been compiled into \*(UA, then this mode
4253 gives the user the option to specify input and output character sets,
4254 unless the file extension indicates binary content, in which case \*(UA
4255 asks wether this step shall be skipped for the attachment in question.
4256 If not skipped, then the charset that succeeds to represent the
4257 attachment data will be used in the
4259 MIME parameter of the mail message:
4261 .Bl -bullet -compact
4263 If input and output character sets are specified, then the conversion is
4264 performed on the fly.
4265 The user will be asked repeatedly until the desired conversion succeeds.
4267 If only an output character set is specified, then the input is assumed
4270 charset and will be converted to the given output charset on the fly.
4271 The user will be asked repeatedly until the desired conversion succeeds.
4273 If no character sets are specified at all then the algorithm that is
4274 documented in the section
4275 .Sx "Character sets"
4276 is applied, but directly and on the fly.
4277 The user will be asked repeatedly until the desired conversion succeeds.
4279 Finally, if an input-, but no output character set is specified, then no
4280 conversion is ever performed, but the
4282 MIME parameter value will still be set to the user input.
4284 The character set selection loop can be left by typing
4286 i.e., causing an interrupt.
4287 .\" \*(OU next sentence
4288 Note that before \*(UA version 15.0 this terminates the entire
4289 current attachment selection, not only the character set selection.
4292 Without character set conversion support, \*(UA will ask for the input
4293 character set only, and it'll set the
4295 MIME parameter value to the given input, if any;
4296 if no user input is seen then the
4298 character set will be used for the parameter value instead.
4299 Note that the file extension check isn't performed in this mode, since
4300 no conversion will take place anyway.
4302 Note that in non-interactive mode, for reproduceabilities sake, there
4303 will always be two questions for each attachment, regardless of wether
4304 character set conversion is available and what the file extension is.
4305 The first asks for the filename, and the second asks for the input
4306 character set to be passed through to the corresponding MIME parameter;
4307 no conversion will be tried if there is input to the latter question,
4308 otherwise the usual conversion algorithm, as above, is applied.
4309 For message attachments, the answer to the second question is completely
4314 arguments are specified for the
4316 command they are treated as a comma separated list of files,
4317 which are all expanded and appended to the end of the attachment list.
4318 (Filenames with commas, or with leading or trailing whitespace can only
4319 be added via the command line or the first method.
4320 Message attachments can only be added via the first method;
4321 filenames which clash with message numbers can only be added via the
4322 command line or the second method.)
4323 In this mode the (text) attachments are assumed to be in
4325 encoding, and will be evaluated as documented in the section
4326 .Sx "Character sets" .
4330 Inserts the string contained in the
4333 .Ql Ic ~i Ns \0Sign ) .
4334 The escape sequences tabulator
4342 Inserts the string contained in the
4345 .Ql Ic ~i Ns \0sign ) .
4346 The escape sequences tabulator
4353 .It Ic ~b Ar name ...
4354 Add the given names to the list of blind carbon copy recipients.
4357 .It Ic ~c Ar name ...
4358 Add the given names to the list of carbon copy recipients.
4362 Read the file specified by the
4364 variable into the message.
4368 Invoke the text editor on the message collected so far.
4369 After the editing session is finished,
4370 the user may continue appending text to the message.
4373 .It Ic ~F Ar messages
4374 Read the named messages into the message being sent, including all
4375 message headers and MIME parts.
4376 If no messages are specified, read in the current message.
4379 .It Ic ~f Ar messages
4380 Read the named messages into the message being sent.
4381 If no messages are specified, read in the current message.
4385 lists are used to modify the message headers.
4386 For MIME multipart messages,
4387 only the first printable part is included.
4391 Edit the message header fields
4397 by typing each one in turn and allowing the user to edit the field.
4398 The default values for these fields originate from the
4399 .Va from , replyto , sender
4406 Edit the message header fields
4412 by typing each one in turn and allowing the user to edit the field.
4415 .It Ic ~i Ar variable
4416 Insert the value of the specified variable into the message,
4417 adding a newline character at the end.
4418 The message remains unaltered if the variable is unset or empty.
4419 The escape sequences tabulator
4426 .It Ic ~M Ar messages
4427 Read the named messages into the message being sent,
4430 If no messages are specified, read the current message.
4433 .It Ic ~m Ar messages
4434 Read the named messages into the message being sent,
4437 If no messages are specified, read the current message.
4441 lists are used to modify the message headers.
4442 For MIME multipart messages,
4443 only the first printable part is included.
4447 Print out the message collected so far,
4448 prefaced by the message header fields
4449 and followed by the attachment list, if any.
4453 Abort the message being sent,
4454 copying it to the file specified by the
4461 .It Ic ~R Ar filename
4462 Read the named file into the message, indented by
4466 .It Ic ~r Ar filename
4467 Read the named file into the message.
4471 Cause the named string to become the current subject field.
4474 .It Ic ~t Ar name ...
4475 Add the given name(s) to the direct recipient list.
4478 .It Ic ~U Ar messages
4479 Read in the given / current message(s) excluding all headers, indented by
4483 .It Ic ~u Ar messages
4484 Read in the given / current message(s), excluding all headers.
4488 Invoke an alternate editor (defined by the
4490 option) on the message collected so far.
4491 Usually, the alternate editor will be a screen editor.
4492 After the editor is quit,
4493 the user may resume appending text to the end of the message.
4496 .It Ic ~w Ar filename
4497 Write the message onto the named file.
4499 the message is appended to it.
4505 except that the message is not saved at all.
4508 .It Ic ~| Ar command
4509 Pipe the message through the specified filter command.
4510 If the command gives no output or terminates abnormally,
4511 retain the original text of the message.
4514 is often used as a rejustifying filter.
4519 .\" .Sh VARIABLE OPTIONS {{{
4520 .Sh "VARIABLE OPTIONS"
4522 Variables are controlled via
4526 commands; in general using
4528 can also be accomplished by prefixing a variable name with the string
4534 will have the same effect as
4536 Creation or editing of variables in an editor can also be achieved with
4539 will give more insight on the given variable(s), whereas
4541 will print a listing of all variables when called without arguments.
4542 Options are also implicitly inherited from the program
4544 and can be set explicitly via the command line option
4548 Different kind of options exist:
4549 binary options, which can only be in one of the two states
4553 as well as value options which have an assigned string value, for which
4554 proper quoting may be important upon assignment time.
4556 .\" .Ss "Initial settings" {{{
4557 .\" (Keep in sync: ./main.c:_startup(), ./nail.rc, ./nail.1:"Initial settings"!)
4558 .Ss "Initial Settings"
4560 The standard POSIX 2008/Cor 1-2013 mandates the following initial
4566 .Pf no Va autoprint ,
4580 .Pf no Va ignoreeof ,
4582 .Pf no Va keepsave ,
4584 .Pf no Va outfolder ,
4589 (note that \*(UA deviates from the standard by using
4593 special prompt escape results in
4595 being printed unless
4601 .Pf no Va sendwait ,
4610 Notes: \*(UA doesn't support the
4612 variable \(en use command line options or
4613 .Va sendmail-arguments
4614 to pass options through to a MTA.
4615 And the default global
4617 file (which is loaded unless the
4619 command line flag has been used or the
4620 .Ev NAIL_NO_SYSTEM_RC
4621 environment variable is set) bends those initial settings a bit, e.g.,
4627 to name a few, calls
4629 etc., and should thus be taken into account.
4632 .\" .Ss "Binary options" {{{
4633 .Ss "Binary options"
4635 .Bl -tag -width ".Va _utoprin_"
4637 .It Va add-file-recipients
4638 When file or pipe recipients have been specified,
4639 mention them in the corresponding address fields of the message instead
4640 of silently stripping them from their recipient list.
4641 By default such addressees are not mentioned.
4645 Causes only the local part to be evaluated
4646 when comparing addresses.
4650 Causes messages saved in
4652 to be appended to the end rather than prepended.
4653 This should always be set.
4657 .It Va ask Ns \0or Va asksub
4658 Causes \*(UA to prompt for the subject of each message sent.
4659 If the user responds with simply a newline,
4660 no subject field will be sent.
4664 Causes the prompts for
4668 lists to appear after the message has been edited.
4672 If set, \*(UA asks for files to attach at the end of each message, shall
4673 the list be found empty at that time.
4674 An empty line finalizes the list.
4678 Causes the user to be prompted for carbon copy recipients
4679 (at the end of each message if
4683 are set) shall the list be found empty (at that time).
4684 An empty line finalizes the list.
4688 Causes the user to be prompted for blind carbon copy
4689 recipients (at the end of each message if
4693 are set) shall the list be found empty (at that time).
4694 An empty line finalizes the list.
4698 \*(OP Causes the user to be prompted if the message is to be signed at
4699 the end of each message.
4702 variable is ignored when this variable is set.
4706 Causes threads to be collapsed automatically when threaded mode is
4713 Causes the delete command to behave like
4715 thus, after deleting a message the next one will be typed automatically.
4719 \*(OB Causes threaded mode (see the
4721 command) to be entered automatically when a folder is opened.
4723 .Ql autosort=thread .
4727 Enables the substitution of
4729 by the contents of the last command line in shell escapes.
4732 .It Va batch-exit-on-error
4733 If the batch mode has been enabled via the
4735 command line option, then this variable will be consulted whenever \*(UA
4736 completes one operation (returns to the command prompt); if it is set
4737 then \*(UA will terminate if the last operation generated an error.
4741 Causes automatic display of a header summary after executing a
4747 Sets some cosmetical features to traditional BSD style;
4748 has the same affect as setting
4750 and all other variables prefixed with
4752 it also changes the meaning of the \*(UA specific
4759 Changes the letters printed in the first column of a header summary
4760 to traditional BSD style.
4764 Changes the display of columns in a header summary to traditional BSD
4769 Changes some informational messages to traditional BSD style.
4775 field to appear immediately after the
4777 field in message headers and with the
4779 .Sx "TILDE ESCAPES" .
4783 Changes the output format of the
4785 command to traditional BSD style.
4788 .It Va colour-disable
4789 \*(OP Forcefully disable usage of colours.
4790 Also see the section
4791 .Sx "Coloured message display" .
4795 \*(OP Wether colour shall be used for output that is paged through
4797 Note that pagers may need special flags, e.g.,
4805 in order to support colours; therefore \*(UA will inspect the variable
4807 \(en if that starts with the string
4809 a non-existing environment variable
4816 will optionally be set to
4818 Also see the section
4819 .Sx "Coloured message display"
4824 Prints debugging messages and disables the actual delivery of messages.
4832 \*(OP When an IMAP mailbox is selected and this variable is set,
4833 no connection to the server is initiated.
4834 Instead, data is obtained from the local cache (see
4837 Mailboxes that are not present in the cache
4838 and messages that have not yet entirely been fetched from the server
4840 to fetch all messages in a mailbox at once,
4842 .No ` Ns Li copy * /dev/null Ns '
4843 can be used while still in connected mode.
4844 Changes that are made to IMAP mailboxes in disconnected mode are queued
4845 and committed later when a connection to that server is made.
4846 This procedure is not completely reliable since it cannot be guaranteed
4847 that the IMAP unique identifiers (UIDs) on the server still match the
4848 ones in the cache at that time.
4851 when this problem occurs.
4853 .It Va disconnected-USER@HOST
4854 The specified account is handled as described for the
4857 but other accounts are not affected.
4860 .It Va disposition-notification-send
4862 .Ql Disposition-Notification-To:
4863 header (RFC 3798) with the message.
4867 .\" TODO .It Va disposition-notification-send-HOST
4869 .\".Va disposition-notification-send
4870 .\" for SMTP accounts on a specific host.
4871 .\" TODO .It Va disposition-notification-send-USER@HOST
4873 .\".Va disposition-notification-send
4874 .\"for a specific account.
4878 When dot is set, a dot
4880 on a line by itself during message input from a terminal shall be
4881 treated as end-of-message (in addition to the normal end-of-file
4887 is ignored and using a dot is the only method to terminate input mode.
4890 .It Va dotlock-ignore-error
4891 \*(OP Synchronization of mailboxes which \*(UA treats as system
4892 mailboxes (see the command
4894 will be protected with so-called dotlock files\(emthe traditional mail
4895 spool file locking method\(emin addition to system file locking.
4896 Because \*(UA ships with a privilege-separated dotlock creation program
4897 that should always be able to create such a dotlock file there is no
4898 good reason to ignore dotlock file creation errors, and thus these are
4899 fatal unless this variable is set.
4903 If this variable is set then the editor is started automatically when
4904 a message is composed in interactive mode, as if the
4910 variable is implied for this automatically spawned editor session.
4914 When a message is edited while being composed,
4915 its header is included in the editable text.
4926 fields are accepted within the header, other fields are ignored.
4930 If the mailbox is empty \*(UA normally prints
4931 .Dq \&No mail for user
4932 and exits immediately.
4933 If this option is set \*(UA starts even with an empty mailbox.
4937 This option reverses the meanings of a set of reply commands,
4938 turning the lowercase variants, which by default address all recipients
4939 included in the header of a message
4940 .Pf ( Ic reply , respond , followup )
4941 into the uppercase variants, which by default address the sender only
4942 .Pf ( Ic Reply , Respond , Followup )
4945 .Ic replysender , respondsender , followupsender
4947 .Ic replyall , respondall , followupall
4948 are not affected by the current setting of
4954 .Ql Mail-Followup-To:
4955 header is generated when sending messages to known mailing lists.
4957 .Va followup-to-honour
4959 .Ic mlist , mlsubscribe , reply
4964 .It Va forward-as-attachment
4965 Original messages are normally sent as inline text with the
4968 and only the first part of a multipart message is included.
4969 With this option messages are sent as unmodified MIME
4971 attachments with all of their parts included.
4975 When replying to or forwarding a message \*(UA normally removes the
4976 comment and name parts of email addresses.
4977 If this variable is set such stripping is not performed,
4978 and comments, names etc. are retained.
4982 Causes the header summary to be written at startup and after commands
4983 that affect the number of messages or the order of messages in the
4984 current folder; enabled by default.
4985 The command line option
4991 .It Va history-gabby
4992 \*(OP Add more entries to the history as is normally done.
4995 .It Va history-gabby-persist
4996 \*(OP \*(UAs own NCL will not save the additional (gabby) history
4997 entries in persistent storage unless this variable is also set.
5003 This option is used to hold messages in the system mailbox by default.
5007 \*(OP Can be used to turn off the automatic conversion of domain names
5008 according to the rules of IDNA (internationalized domain names for
5010 Since the IDNA code assumes that domain names are specified with the
5012 character set, an UTF-8 locale charset is required to represent all
5013 possible international domain names (before conversion, that is).
5017 Ignore interrupt signals from the terminal while entering messages;
5018 instead echo them as
5020 characters and discard the current line.
5024 Ignore end-of-file conditions
5025 .Pf ( Ql control-D ) ,
5026 on message input, which instead can be terminated only by entering a
5029 on a line by itself or by using the
5031 .Sx "TILDE ESCAPES" .
5032 This option also applies to \*(UA command mode.
5034 .Mx Va imap-use-starttls
5035 .It Va imap-use-starttls-USER@HOST , imap-use-starttls-HOST , imap-use-starttls
5036 \*(OP Causes \*(UA to issue a `STARTTLS' command to make an unencrypted
5037 IMAP session SSL/TLS encrypted.
5038 This functionality is not supported by all servers,
5039 and is not used if the session is already encrypted by the IMAPS method.
5043 If set, an empty mailbox file is not removed.
5044 This may improve the interoperability with other mail user agents
5045 when using a common folder directory, and prevents malicious users
5046 from creating fake mailboxes in a world-writable spool directory.
5047 Note this only applies to local regular (MBOX) files, other mailbox
5048 types will never be removed.
5052 When a message is saved it is usually discarded from the originating
5053 folder when \*(UA is quit.
5054 Setting this option causes all saved message to be retained.
5057 .It Va line-editor-disable
5058 Turn off any enhanced command line editing capabilities (see
5059 .Sx "Command line editor"
5064 When a message is replied to and this variable is set,
5065 it is marked as having been answered.
5066 This mark has no technical meaning in the mail system;
5067 it just causes messages to be marked in the header summary,
5068 and makes them specially addressable.
5072 \*(UA produces and expects fully RFC 4155 compliant MBOX text mailboxes.
5073 Messages which are fetched over the network or from within already
5074 existing Maildir (or any non-MBOX) mailboxes may require so-called
5076 quoting (insertion of additional
5078 characters to prevent line content misinterpretation) to be applied in
5079 order to be storable in MBOX mailboxes, however, dependent on the
5080 circumspection of the message producer.
5081 (E.g., \*(UA itself will, when newly generating messages, choose a
5082 .Pf Content-Transfer- Va encoding
5083 that prevents the necessity for such quoting \(en a necessary
5084 precondition to ensure message checksums won't change.)
5086 By default \*(UA will perform this
5088 quoting in a way that results in a MBOX file that is compatible with
5089 the loose POSIX MBOX layout, in order not to exceed the capabilities
5090 of simple applications, however.
5091 Set this option to generate MBOX files for RFC 4155 compliant
5095 .It Va message-id-disable
5096 By setting this option the generation of
5098 can be completely suppressed, effectively leaving this task up to the
5099 mail-transfer-agent (MTA) or the SMTP server.
5100 (According to RFC 5321 your SMTP server is not required to add this
5101 field by itself, so you should ensure that it accepts messages without a
5108 expansion contains the sender, the sender is removed from the expansion.
5109 Setting this option suppresses these removals.
5114 option to be passed to mail-transfer-agents (MTAs);
5115 though most of the modern MTAs don't (no longer) document this flag, no
5116 MTA is known which doesn't support it (for historical compatibility).
5119 .It Va mime-allow-text-controls
5120 When sending messages, each part of the message is MIME-inspected in
5121 order to classify the
5124 .Ql Content-Transfer-Encoding:
5127 that is required to send this part over mail transport, i.e.,
5128 a computation rather similar to what the
5130 command produces when used with the
5134 This classification however treats text files which are encoded in
5135 UTF-16 (seen for HTML files) and similar character sets as binary
5136 octet-streams, forcefully changing any
5141 .Ql application/octet-stream :
5142 If that actually happens a yet unset charset MIME parameter is set to
5144 effectively making it impossible for the receiving MUA to automatically
5145 interpret the contents of the part.
5147 If this option is set, and the data was unambiguously identified as text
5148 data at first glance (by a
5152 file extension), then the original
5154 will not be overwritten.
5157 .It Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup
5158 \*(IN \*(OP Used to control usage of the users
5160 file for lookup of account credentials, as documented in the section
5161 .Sx "On URL syntax and credential lookup"
5165 .Sx "The .netrc file"
5166 documents the file format.
5170 Causes the filename given in the
5173 and the sender-based filenames for the
5177 commands to be interpreted relative to the directory given in the
5179 variable rather than to the current directory,
5180 unless it is set to an absolute pathname.
5184 If set, each message the
5186 command prints out is followed by a formfeed character
5191 Send messages to the
5193 command without performing MIME and character set conversions.
5196 .Mx Va pop3-bulk-load
5197 .It Va pop3-bulk-load-USER@HOST , pop3-bulk-load-HOST , pop3-bulk-load
5198 \*(OP When accessing a POP3 server \*(UA loads the headers of the
5199 messages, and only requests the message bodies on user request.
5200 For the POP3 protocol this means that the message headers will be
5202 If this option is set then \*(UA will download only complete messages
5203 from the given POP3 server(s) instead.
5206 .It Va pop3-no-apop-USER@HOST , pop3-no-apop-HOST , pop3-no-apop
5207 \*(OP Unless this variable is set the
5209 authentication method will be used when connecting to a POP3 server that
5213 is that the password is not sent in clear text over the wire and that
5214 only a single packet is sent for the user/password tuple.
5216 .Va pop3-no-apop-HOST
5219 .Mx Va pop3-use-starttls
5220 .It Va pop3-use-starttls-USER@HOST , pop3-use-starttls-HOST , pop3-use-starttls
5221 \*(OP Causes \*(UA to issue a
5223 command to make an unencrypted POP3 session SSL/TLS encrypted.
5224 This functionality is not supported by all servers,
5225 and is not used if the session is already encrypted by the POP3S method.
5227 .Va pop3-use-starttls-HOST
5231 .It Va print-all-chars
5232 This option causes all characters to be considered printable.
5233 It is only effective if given in a startup file.
5234 With this option set some character sequences in messages may put the
5235 user's terminal in an undefined state when printed;
5236 it should only be used as a last resort if no working system locale can
5240 .It Va print-alternatives
5241 When a MIME message part of type
5242 .Ql multipart/alternative
5243 is displayed and it contains a subpart of type
5245 other parts are normally discarded.
5246 Setting this variable causes all subparts to be displayed,
5247 just as if the surrounding part was of type
5248 .Ql multipart/mixed .
5252 Suppresses the printing of the version when first invoked.
5255 .It Va quote-as-attachment
5256 If this is set, then the original message is added in its entirety as a
5258 MIME attachment when replying to a message.
5259 Note this works regardless of the setting of
5263 .It Va recipients-in-cc
5264 On group replies, specify only the sender of the original mail in
5266 and mention the other recipients in the secondary
5268 By default all recipients of the original mail will be addressed via
5272 .It Va record-resent
5273 If both this variable and the
5280 commands save messages to the
5282 folder as it is normally only done for newly composed messages.
5285 .It Va reply-in-same-charset
5286 If this variable is set \*(UA first tries to use the same character set
5287 of the original message for replies.
5288 If this fails, the mechanism described in
5289 .Sx "Character sets"
5290 is evaluated as usual.
5293 .It Va rfc822-body-from_
5294 This variable can be used to force displaying a so-called
5296 line for messages that are embedded into an envelope mail via the
5298 MIME mechanism, for more visual convenience.
5302 Enable saving of (partial) messages in
5304 upon interrupt or delivery error.
5307 .It Va searchheaders
5308 Expand message-list specifiers in the form
5310 to all messages containing the substring
5314 The string search is case insensitive.
5317 .It Va sendcharsets-else-ttycharset
5318 \*(OP If this variable is set, but
5320 is not, then \*(UA acts as if
5322 had been set to the value of the variable
5324 In effect this combination passes through the message data in the
5325 character set of the current locale (given that
5327 hasn't been set manually), i.e., without converting it to the
5329 fallback character set.
5330 Thus, mail message text will be in ISO-8859-1 encoding when send from
5331 within a ISO-8859-1 locale, and in UTF-8 encoding when send from within
5333 If no character set conversion capabilities are available in \*(UA then
5334 the only supported character set is
5337 .It Va sendmail-no-default-arguments
5338 Unless this option is set \*(UA will pass some well known
5339 standard command line options to the defined
5341 program, see there for more.
5345 When sending a message wait until the MTA (including the builtin SMTP
5346 one) exits before accepting further commands.
5348 with this variable set errors reported by the MTA will be recognizable!
5349 If the MTA returns a non-zero exit status,
5350 the exit status of \*(ua will also be non-zero.
5354 Setting this option causes \*(UA to start at the last message instead of
5355 the first one when opening a mail folder.
5359 Causes \*(UA to use the sender's real name instead of the plain address
5360 in the header field summary and in message specifications.
5364 Causes the recipient of the message to be shown in the header summary
5365 if the message was sent by the user.
5368 .It Va skipemptybody
5369 If an outgoing message does not contain any text in its first or only
5371 do not send it but discard it silently (see also the command line option
5375 .It Va smime-force-encryption
5376 \*(OP Causes \*(UA to refuse sending unencrypted messages.
5380 \*(OP S/MIME sign outgoing messages with the user's private key and
5381 include the user's certificate as a MIME attachment.
5382 Signing a message enables a recipient to verify that the sender used
5383 a valid certificate,
5384 that the email addresses in the certificate match those in the message
5385 header and that the message content has not been altered.
5386 It does not change the message text,
5387 and people will be able to read the message as usual.
5389 .Va smime-sign-cert , smime-sign-include-certs
5391 .Va smime-sign-message-digest .
5394 .It Va smime-no-default-ca
5395 \*(OP Don't load default CA locations when verifying S/MIME signed
5398 .Mx Va smtp-use-starttls
5399 .It Va smtp-use-starttls-USER@HOST , smtp-use-starttls-HOST , smtp-use-starttls
5400 \*(OP Causes \*(UA to issue a
5402 command to make an SMTP session SSL/TLS encrypted, i.e., to enable
5403 transport layer security.
5406 .It Va ssl-no-default-ca
5407 \*(OP Don't load default CA locations to verify SSL/TLS server
5412 \*(OP If terminal capability queries are supported and this option is
5413 set then \*(UA will try to switch to the
5414 .Dq alternate screen
5415 when in interactive mode, so that the terminal will go back to the
5416 normal screen, leaving all the text there intact, when \*(UA exits.
5418 even when supported for this to produce appealing results the used
5420 and possibly configured
5421 .Va pipe-TYPE/SUBTYPE
5422 applications that take control over the terminal need to have
5423 corresponding support too, e.g., the
5425 pager should be driven with the
5430 .It Va keep-content-length
5431 When (editing messages and) writing
5433 mailbox files \*(UA can be told to keep the
5437 header fields that some MUAs generate by setting this variable.
5438 Since \*(UA does neither use nor update these non-standardized header
5439 fields (which in itself shows one of their conceptual problems),
5440 stripping them should increase interoperability in between MUAs that
5441 work with with same mailbox files.
5442 Note that, if this is not set but
5443 .Va writebackedited ,
5444 as below, is, a possibly performed automatic stripping of these header
5445 fields already marks the message as being modified.
5449 Setting this option enables upward compatibility with \*(UA version 15.0
5450 in respect to which configuration options are available and how they are
5452 This manual uses \*(IN and \*(OU to refer to the new and the old way of
5453 doing things, respectively.
5457 Setting this option, also controllable via the command line option
5459 causes \*(UA to be more verbose, so that, e.g., certificate chains will
5460 be displayed on the users terminal.
5461 Setting this binary option twice increases the level of verbosity, in
5462 which case even details of the actual message delivery and protocol
5463 conversations are shown.
5466 is sufficient to disable verbosity as such.
5469 .It Va writebackedited
5470 If this variable is set messages modified using the
5474 commands are written back to the current folder when it is quit;
5475 it is only honoured for writable folders in MBOX format, though.
5476 Note that the editor will be pointed to the raw message content in that
5477 case, i.e., neither MIME decoding nor decryption will have been
5478 performed, and proper RFC 4155
5480 quoting of newly added or edited content is also left as an excercise to
5485 .\" .Ss "Value options" {{{
5488 Options with values that are generally treated as strings.
5489 To embed whitespace (space and tabulator) in a value it either needs to
5490 be escaped with a backslash character, or the entire value must be
5491 enclosed in (double or single) quotation marks;
5492 To use quotation marks identical to those used to enclose the value,
5493 escape them with a backslash character.
5494 The backslash character has no special meaning except in these cases.
5496 .Bd -literal -offset indent
5497 set 1=val\e one 2="val two" 3='val "three"' 4='val \e'four\e''
5503 Booleans are special string values that must either be set to decimal
5504 integers (in which case
5508 and any other value is true) or to any of
5513 for a false boolean and
5518 for a true boolean; matching is performed case-insensitively.
5519 And there exists a special kind of boolean, the
5521 this is expected to either name a boolean or one of the strings
5527 followed by a valid boolean, case-insensitively);
5528 if one of the latter is set then in interactive mode the user will be
5529 prompted with the default value (also used for empty user input) set to
5530 the given boolean, whereas in non-interactive the given default will
5533 .Bl -tag -width ".It Va _utoprin_"
5534 .Mx Va agent-shell-lookup
5535 .It Va agent-shell-lookup-USER@HOST , agent-shell-lookup-HOST , \
5537 \*(IN \*(OP Account passwords can be fetched via an external agent
5538 program in order to permit encrypted password storage \(en see
5539 .Sx "On URL syntax and credential lookup"
5540 for more on credential lookup.
5541 If this is set then the content is interpreted as a shell command the
5542 output of which (with newline characters removed) is treated as the
5543 account password shall the command succeed (and have produced non-empty
5544 non-newline output); e.g., via
5546 .Bd -literal -offset indent
5547 $ echo PASSWORD > .pass
5549 $ eval `gpg-agent --daemon \e
5550 --pinentry-program=/usr/bin/pinentry-curses \e
5551 --max-cache-ttl 99999 --default-cache-ttl 99999`
5552 $ echo 'set agent-shell-lookup="gpg -d .pass.gpg"' \e
5556 A couple of environment variables will be set for the agent:
5558 .Bl -tag -compact -width ".It Ev _AIL_TMPDIR[337]"
5560 The temporary directory that \*(UA uses.
5561 Usually identical to
5563 but guaranteed to be set and usable by child processes;
5564 to ensure the latter condition for
5570 for which the password is looked up.
5571 .It Ev NAIL_USER_ENC
5572 The URL percent-encoded variant of
5575 The plain machine hostname of the user account.
5576 .It Ev NAIL_HOST_PORT
5579 (hostname possibly including port) of the user account.
5584 A sequence of characters to print in the
5588 as shown in the header display; each for one type of messages (see
5589 .Sx "Message states" ) ,
5590 with the default being
5593 .Ql NU\ \ *HMFAT+\-$~
5598 environment variable are set, in the following order:
5600 .Bl -tag -compact -offset indent -width ".It Ql _"
5622 start of a collapsed thread.
5628 classified as possible spam.
5633 Specifies a list of recipients to which a blind carbon copy of each
5634 outgoing message will be sent automatically.
5638 Specifies a list of recipients to which a carbon copy of each outgoing
5639 message will be sent automatically.
5643 Causes sorted mode (see the
5645 command) to be entered automatically with the value of this option as
5646 sorting method when a folder is opened.
5650 The value that should appear in the
5654 MIME header fields when no character set conversion of the message data
5656 This defaults to US-ASCII, and the chosen character set should be
5657 US-ASCII compatible.
5661 \*(OP The default 8-bit character set that is used as an implicit last
5662 member of the variable
5664 This defaults to UTF-8.
5665 If no character set conversion capabilities are available in \*(UA then
5666 the only supported character set is
5668 Refer to the section
5669 .Sx "Character sets"
5670 for the complete picture of character set conversion in \*(UA.
5673 .It Va charset-unknown-8bit
5674 \*(OP RFC 1428 specifies conditions when internet mail gateways shall
5676 the content of a mail message by using a character set with the name
5678 Because of the unclassified nature of this character set \*(UA will not
5679 be capable to convert this character set to any other character set.
5680 If this variable is set any message part which uses the character set
5682 is assumed to really be in the character set given in the value,
5683 otherwise the (final) value of
5685 is used for this purpose.
5689 The default value for the
5695 \*(OP The colour specification for so-called
5699 .Sx "Coloured message display"
5700 for the format of the value.
5703 .It Va colour-header
5704 \*(OP The colour specification for header lines.
5707 .It Va colour-msginfo
5708 \*(OP The colour specification for the introductional message info line.
5711 .It Va colour-partinfo
5712 \*(OP The colour specification for MIME part info lines.
5716 \*(OP A comma-separated list of
5718 inals for which coloured message display can be used.
5719 Entries only need to be added if the string
5721 isn't part of the terminal name itself; the default value is
5723 .Dl cons25,linux,rxvt,rxvt-unicode,\:screen,\:sun,\:vt100,\:vt220,\:\
5727 .It Va colour-uheader
5728 \*(OP The colour specification for those header lines that have been
5730 .Va colour-user-headers
5733 .Sx "Coloured message display" .
5736 .It Va colour-user-headers
5737 A comma separated list of (case-insensitive) header names which should
5738 be colourized with the alternative
5741 The default value is
5746 In a(n interactive) terminal session, then if this valued option is set
5747 it'll be used as a threshold to determine how many lines the given
5748 output has to span before it will be displayed via the configured
5752 can be forced by setting this to the value
5754 setting it without a value will deduce the current height of the
5755 terminal screen to compute the treshold (see
5762 The date in a header summary is normally the date of the mailbox
5764 line of the message.
5765 If this variable is set, then the date as given in the
5767 field is used, converted to local time.
5768 It is possible to control the display of the date by assigning a value,
5771 function will be used to format the date accordingly.
5772 Please read your system manual for the available formats.
5775 format should not be used, because \*(UA doesn't take embedded newlines
5776 into account when calculating how many lines fit onto the screen.
5779 .It Va datefield-markout-older
5780 This option, when set in addition to
5784 messages (concept is rather comparable to the
5786 option of the POSIX utility
5788 The content interpretation is identical to
5793 Suggestion for the MIME encoding to use in outgoing text messages
5795 Valid values are the default
5796 .Ql quoted-printable ,
5801 may cause problems when transferring mail messages over channels that
5802 are not ESMTP (RFC 1869) compliant.
5803 If there is no need to encode a message,
5805 transfer mode is always used regardless of this variable.
5806 Binary data is always encoded as
5811 If defined, the first character of this option
5812 gives the character to use in place of
5815 .Sx "TILDE ESCAPES" .
5819 If not set then file and command pipeline targets are not allowed,
5820 and any such address will be filtered out, giving a warning message.
5821 If set without a value then all possible recipient address
5822 specifications will be accepted \(en see the section
5825 To accept them, but only in interactive mode, or when tilde commands
5826 were enabled explicitly by using one of the command line options
5830 set this to the (case-insensitive) value
5832 (note right now this is actually like setting
5833 .Ql restrict,-all,+name,+addr ) .
5835 In fact the value is interpreted as a comma-separated list of values.
5838 then the existence of disallowed specifications is treated as a hard
5839 send error instead of only filtering them out.
5840 The remaining values specify wether a specific type of recipient
5841 address specification is allowed (optionally indicated by a plus sign
5843 prefix) or disallowed (prefixed with a hyphen
5847 addresses all possible address specifications,
5851 command pipeline targets,
5853 plain user names and (MTA) aliases (\*(OB
5855 may be used as an alternative syntax to
5860 These kind of values are interpreted in the given order, so that
5861 .Ql restrict,\:fail,\:+file,\:-all,\:+addr
5862 will cause hard errors for any non-network address recipient address
5863 unless \*(UA is in interactive mode or has been started with the
5867 command line option; in the latter case(s) any address may be used, then.
5871 Unless this variable is set additional mail-transfer-agent (MTA)
5872 arguments from the command line, as can be given after a
5874 separator, are ignored due to safety reasons.
5875 However, if set to the special value
5877 then the presence of additional MTA arguments is treated as a hard
5878 error that causes \*(UA to exit with failure status.
5879 A lesser strict variant is the otherwise identical
5881 which does accept such arguments in interactive mode, or if tilde
5882 commands were enabled explicitly by using one of the command line options
5889 \*(RO Information on the features compiled into \*(UA \(en the content
5890 of this variable is identical to the output of the command
5895 .It Va file-hook-load-EXTENSION , file-hook-save-EXTENSION
5896 It is possible to install file hooks which will be used by the
5898 command in order to be able to transparently handle (through an
5899 intermediate temporary file) files with specific
5901 s: the variable values can include shell snippets and are expected to
5902 write data to standard output / read data from standard input,
5904 \*(ID The variables may not be changed while there is a mailbox
5906 .Bd -literal -offset indent
5907 set file-hook-load-xy='echo >&2 XY-LOAD; gzip -cd' \e
5908 file-hook-save-xy='echo >&2 XY-SAVE; gzip -c' \e
5909 record=+null-sent.xy
5914 The name of the directory to use for storing folders of messages.
5915 All folder names that begin with
5917 refer to files below it.
5918 The same special conventions as documented for the
5920 command may be used when specifying a new value for
5922 but be aware that the expansion is fully performed immediately.
5923 E.g., if the expanded name refers to an IMAP account, all names that
5924 begin with `+' refer to IMAP mailboxes below the
5928 Note: some IMAP servers do not accept the creation of mailboxes in
5929 the hierarchy base, but require that they are created as subfolders of
5930 `INBOX' \(en with such servers a folder name of the form
5932 .Dl imaps://mylogin@imap.myisp.example/INBOX.
5934 should be used (the last character is the server's hierarchy delimiter).
5935 Folder names prefixed by `+' will then refer to folders below `INBOX',
5936 while folder names prefixed by `@' refer to folders below the hierarchy
5940 namespace command for a method to detect the appropriate prefix and
5945 When a folder is opened and this variable is set,
5946 the macro corresponding to the value of this variable is executed.
5947 The macro is also invoked when new mail arrives,
5948 but message lists for commands executed from the macro
5949 only include newly arrived messages then.
5952 are activated in a folder hook, then the covered settings will be
5953 reverted once the folder is left again.
5956 .It Va folder-hook-FOLDER
5961 Unlike other folder specifications, the fully expanded name of a folder,
5962 without metacharacters, is used to avoid ambiguities.
5963 However, if the mailbox resides under
5967 specification is tried in addition, e.g., if
5971 (and thus relative to the user's home directory) then
5972 .Pa /home/usr1/mail/sent
5974 .Ql folder-hook-/home/usr1/mail/sent
5975 first, but then followed by
5976 .Ql folder-hook-+sent .
5979 .It Va followup-to-honour
5981 .Ql Mail-Followup-To:
5982 header is honoured when group-replying to a message via
5986 This is a quadoption; if set without a value it defaults to
5997 The address (or a list of addresses) to put into the
5999 field of the message header, quoting RFC 5322:
6000 the author(s) of the message, that is, the mailbox(es) of the person(s)
6001 or system(s) responsible for the writing of the message.
6002 If replying to messages these addresses are handled as if they were in
6006 If the machine's hostname is not valid at the Internet (for example at
6007 a dialup machine) then either this variable or
6012 adds even more fine-tuning capabilities),
6016 contains more than one address,
6019 variable is required (according to the standard RFC 5322).
6023 The string to print before the text of a message with the
6027 .Va forward-as-attachment
6030 .Dq -------- Original Message --------
6031 if unset; No heading is printed if it is set to the empty string.
6035 A format string to use for the header summary,
6041 introduces a format specifier that may be followed by a number
6042 indicating the field width;
6043 If the (possibly implicitly implied) field width is negative, the field
6044 is to be left-aligned.
6045 Valid format specifiers are:
6047 .Bl -tag -compact -offset indent -width "_%%_"
6049 A plain percent character.
6051 A space character but for the current message, for which it expands to
6054 A space character but for the current message, for which it expands to
6057 \*(OP The spam score of the message, as has been classified via the
6060 Prints only a replacement character if there is no spam support.
6062 Message attribute character (status flag); the actual content can be
6066 The date when the message was received.
6068 The indenting level in threaded mode.
6070 The address of the message sender.
6072 The message thread structure.
6073 (Note that this format doesn't support a field width.)
6075 The number of lines of the message.
6079 The number of octets (bytes) in the message.
6081 Message subject (if any).
6083 Message subject (if any) in double quotes.
6085 Message recipient flags: is the addressee of the message a known or
6086 subscribed mailing list \(en see
6091 The position in threaded/sorted order.
6095 .Ql %>\&%a\&%m\ %-18f\ %16d\ %4l/%\-5o\ %i%-s ,
6097 .Ql %>\&%a\&%m\ %20-f\ \ %16d\ %3l/%\-5o\ %i%-S
6107 .It Va headline-bidi
6108 Bidirectional text requires special treatment when displaying headers,
6109 because numbers (in dates or for file sizes etc.) will not affect the
6110 current text direction, in effect resulting in ugly line layouts when
6111 arabic or other right-to-left text is to be displayed.
6112 On the other hand only a minority of terminals is capable to correctly
6113 handle direction changes, so that user interaction is necessary for
6115 Note that extended host system support is required nonetheless, e.g.,
6116 detection of the terminal character set is one precondition;
6117 and this feature only works in an Unicode (i.e., UTF-8) locale.
6119 In general setting this variable will cause \*(UA to encapsulate text
6120 fields that may occur when printing
6122 (and some other fields, like dynamic expansions in
6124 with special Unicode control sequences;
6125 it is possible to fine-tune the terminal support level by assigning
6127 no value (or any value other than
6132 will make \*(UA assume that the terminal is capable to properly deal
6133 with Unicode version 6.3, in which case text is embedded in a pair of
6134 U+2068 (FIRST STRONG ISOLATE) and U+2069 (POP DIRECTIONAL ISOLATE)
6136 In addition no space on the line is reserved for these characters.
6138 Weaker support is chosen by using the value
6140 (Unicode 6.3, but reserve the room of two spaces for writing the control
6141 sequences onto the line).
6146 select Unicode 1.1 support (U+200E, LEFT-TO-RIGHT MARK); the latter
6147 again reserves room for two spaces in addition.
6151 Use this string as hostname when expanding local addresses instead of
6152 the value obtained from
6163 transport is not used then it is normally the responsibility of the MTA
6164 to create these fields, \*(IN in conjunction with
6168 also influences the results;
6169 you should produce some test messages with the desired combination of
6177 .It Va imap-auth-USER@HOST , imap-auth
6178 \*(OP Sets the IMAP authentication method.
6179 Valid values are `login' for the usual password-based authentication
6181 `cram-md5', which is a password-based authentication that does not send
6182 the password over the network in clear text,
6183 and `gssapi' for GSS-API based authentication.
6187 \*(OP Enables caching of IMAP mailboxes.
6188 The value of this variable must point to a directory that is either
6189 existent or can be created by \*(UA.
6190 All contents of the cache can be deleted by \*(UA at any time;
6191 it is not safe to make assumptions about them.
6193 .Mx Va imap-keepalive
6194 .It Va imap-keepalive-USER@HOST , imap-keepalive-HOST , imap-keepalive
6195 \*(OP IMAP servers may close the connection after a period of
6196 inactivity; the standard requires this to be at least 30 minutes,
6197 but practical experience may vary.
6198 Setting this variable to a numeric `value' greater than 0 causes
6199 a `NOOP' command to be sent each `value' seconds if no other operation
6203 .It Va imap-list-depth
6204 \*(OP When retrieving the list of folders on an IMAP server, the
6206 command stops after it has reached a certain depth to avoid possible
6208 The value of this variable sets the maximum depth allowed.
6210 If the folder separator on the current IMAP server is a slash `/',
6211 this variable has no effect and the
6213 command does not descend to subfolders.
6224 option for indenting messages,
6225 in place of the normal tabulator character
6227 which is the default.
6228 Be sure to quote the value if it contains spaces or tabs.
6231 .It Va line-editor-cursor-right
6232 \*(OP If the builtin command line editor is used, actions which are
6233 based on rightwise movement may not work on some terminals.
6234 If you encounter such problems, set this variable to the terminal
6235 control sequence that is necessary to move the cursor one column to the
6239 which should work for most terminals.
6246 and other control character have to be written as shell-style escape
6254 Is used as the user's mailbox, if set.
6255 Otherwise, a system-dependent default is used.
6256 Supports a logical subset of the special conventions that are documented
6264 .It Va mime-counter-evidence
6267 field is used to decide how to handle MIME parts.
6268 Some MUAs however don't use
6270 or a similar mechanism to correctly classify content, but simply specify
6271 .Ql application/octet-stream ,
6272 even for plain text attachments like
6274 If this variable is set then \*(UA will try to classify such MIME
6275 message parts on its own, if possible, and through their file name.
6276 This variable can also be given a non-empty value, in which case the
6277 value is expected to be a number, actually a carrier of bits.
6278 Creating the bit-carrying number is a simple addition:
6279 .Bd -literal -offset indent
6280 ? !echo Value should be set to $((2 + 4))
6281 Value should be set to 6
6284 .Bl -bullet -compact
6286 If bit two is set (2) then the detected
6288 content-type will be carried along with the message and be used for
6290 .Va pipe-TYPE/SUBTYPE
6291 is responsible for the MIME part, shall that question arise;
6292 when displaying such a MIME part the part-info will indicate the
6293 overridden content-type by showing a plus-sign
6296 If bit three is set (4) then the counter-evidence is always produced
6297 and a positive result will be used as the MIME type, even forcefully
6298 overriding the parts given MIME type.
6300 .\"If bit four is set (8) then as a last resort the content of
6301 .\".Ql application/octet-stream
6302 .\"parts will be inspected, so that data that looks like (english) plain
6303 .\"text can be treated as such.
6307 .It Va mimetypes-load-control
6308 This option can be used to control which of the
6310 databases are loaded by \*(UA, as furtherly described in the section
6311 .Sx "The mime.types files" .
6314 is part of the option value, then the user's personal
6316 file will be loaded (if it exists); likewise the letter
6318 controls loading of the system wide
6319 .Pa /etc/mime.types ;
6320 the user file is loaded first, letter matching is case-insensitive.
6321 If this option is not set \*(UA will try to load both files instead.
6322 Incorporation of the \*(UA-builtin MIME types cannot be suppressed,
6323 but they will be matched last.
6325 More sources can be specified by using a different syntax: if the
6326 value string contains an equals sign
6328 then it is instead parsed as a comma-separated list of the described
6331 pairs; the given filenames will be expanded and loaded, and their
6332 content may use the extended syntax that is described in the section
6333 .Sx "The mime.types files" .
6336 .It Va NAIL_EXTRA_RC
6337 The name of an optional startup file to be read after
6339 This variable has an effect only if it is set in
6343 it is not imported from the environment in order to honour
6344 .Ql MAILRC=/dev/null Ns /
6347 Use this file for commands that are not understood by other POSIX
6353 A string to put at the beginning of each new message.
6354 The escape sequences tabulator
6361 .It Va NAIL_HISTFILE
6362 \*(OP If a command line editor is available then this can be set to
6363 name the (expandable) path of the location of a permanent history file.
6366 .It Va NAIL_HISTSIZE
6367 \*(OP If a command line editor is available this value restricts the
6368 amount of history entries that are saved into a set and valid
6370 A value of less than 0 disables this feature;
6371 note that loading and incorporation of
6373 upon program startup can also be suppressed by doing this.
6374 An unset or invalid value, or 0, causes a default value to be used.
6375 Dependent on the available command line editor this will also define the
6376 number of history entries in memory;
6377 it is also editor-specific wether runtime updates of this value will be
6382 A string to put at the end of each new message.
6383 The escape sequences tabulator
6391 If this variable has the value
6393 newly created local folders will be in Maildir format.
6397 Checks for new mail in the current folder each time the prompt is
6399 For IMAP mailboxes the server is then polled for new mail,
6400 which may result in delayed operation if the connection to the server is
6402 A Maildir folder must be re-scanned to determine if new mail has arrived.
6404 If this variable is set to the special value
6406 an IMAP server is not actively asked for new mail, but new mail may
6407 still be detected and announced with any other IMAP command that is sent
6409 In either case the IMAP server may send notifications about messages
6410 that have been deleted on the server by another process or client.
6412 .Dq Expunged X messages
6413 is printed regardless of this variable, and message numbers may have
6416 If this variable is set to the special value
6418 then a Maildir folder will not be rescanned completely, but only
6419 timestamp changes are detected.
6423 The value to put into the
6425 field of the message header.
6428 .It Va password-USER@HOST , password-HOST , password
6429 \*(IN Variable chain that sets a password, which is used in case none has
6430 been given in the protocol and account-specific URL;
6431 as a last resort \*(UA will ask for a password on the user's terminal if
6432 the authentication method requires a password.
6433 Specifying passwords in a startup file is generally a security risk;
6434 the file should be readable by the invoking user only.
6436 .It Va password-USER@HOST
6437 \*(OU (see the chain above for \*(IN)
6438 Set the password for
6442 If no such variable is defined for a host,
6443 the user will be asked for a password on standard input.
6444 Specifying passwords in a startup file is generally a security risk;
6445 the file should be readable by the invoking user only.
6448 .It Va pipe-TYPE/SUBTYPE
6449 When a MIME message part of type
6451 (normalized to lowercase) is displayed or quoted,
6452 its text is filtered through the value of this variable interpreted as
6456 can be used to force interpretation of the message part as plain text, e.g.,
6457 .Ql set pipe-application/pgp-signature=@
6458 will henceforth treat signatures as plain text and display them "as is".
6459 (The same can also be achieved, in a more useful context, by using the
6461 command in conjunction with a type marker.)
6463 Also, if a shell command is prefixed with
6465 then the command will only be used to prepare the MIME message part if
6466 the message is displayed by itself, but not when multiple messages are
6469 Finally, if a shell command is prefixed with
6471 then, in addition to what has been described for the plain
6473 shell command prefix, the command will be run asynchronously, i.e.,
6474 without blocking \*(UA, which may be a handy way to display a, e.g., PDF
6475 file while also continuing to read the mail message.
6476 Some information about the MIME part to be displayed is embedded into
6477 the environment of the shell command:
6479 .Bl -tag -compact -width ".It Ev _AIL__ILENAME__ENERATED"
6482 The temporary directory that \*(UA uses.
6483 Usually identical to
6485 but guaranteed to be set and usable by child processes;
6486 to ensure the latter condition for
6490 .It Ev NAIL_FILENAME
6491 The filename, if any is set, the empty string otherwise.
6493 .It Ev NAIL_FILENAME_GENERATED
6497 The MIME content-type of the part, if known, the empty string otherwise.
6499 .It Ev NAIL_CONTENT_EVIDENCE
6501 .Va mime-counter-evidence
6502 includes the carry-around-bit (2), then this will be set to the detected
6503 MIME content-type; not only then identical to
6504 .Ev \&\&NAIL_CONTENT
6509 .It Va pipe-EXTENSION
6510 This is identical to
6511 .Va pipe-TYPE/SUBTYPE
6514 (normalized to lowercase using character mappings of the ASCII charset)
6515 names a file extension, e.g.,
6517 Handlers registered using this method take precedence.
6519 .Mx Va pop3-keepalive
6520 .It Va pop3-keepalive-USER@HOST , pop3-keepalive-HOST , pop3-keepalive
6521 \*(OP POP3 servers close the connection after a period of inactivity;
6522 the standard requires this to be at least 10 minutes,
6523 but practical experience may vary.
6524 Setting this variable to a numeric value greater than
6528 command to be sent each value seconds if no other operation is performed.
6532 The string printed when a command is accepted.
6533 Prompting may be prevented by either setting this to the null string
6536 The same XSI escape sequences that are understood by the
6538 command may be used within
6541 In addition, the following \*(UA specific additional sequences are
6548 is set, in which case it expands to
6552 is the default value of
6555 which will expand to
6557 if the last command failed and to
6561 which will expand to the name of the currently active
6563 if any, and to the empty string otherwise, and
6565 which will expand to the name of the currently active mailbox.
6566 (Note that the prompt buffer is size-limited, excess is cut off.)
6572 to encapsulate the expansions of the
6576 escape sequences as necessary to correctly display bidirectional text,
6577 this is not true for the final string that makes up
6579 as such, i.e., real BIDI handling is not supported.
6581 When a newer version of the
6583 .Sx "Command line editor"
6584 is used, any escape sequence must itself be encapsulated with another
6585 escape character for usage with the
6587 mechanism: \*(UA configures the control character
6593 If set, \*(UA starts a replying message with the original message
6594 prefixed by the value of the variable
6596 Normally, a heading consisting of
6597 .Dq Fromheaderfield wrote:
6598 is printed before the quotation.
6603 variable, this heading is omitted.
6606 is assigned, the headers selected by the
6607 .Ic ignore Ns / Ns Ic retain
6608 commands are printed above the message body,
6611 acts like an automatic
6617 is assigned, all headers are printed above the message body and all MIME
6618 parts are included, making
6620 act like an automatic
6623 .Va quote-as-attachment .
6627 \*(OP Can be set in addition to
6629 Setting this turns on a more fancy quotation algorithm in that leading
6630 quotation characters are compressed and overlong lines are folded.
6632 can be set to either one or two (space separated) numeric values,
6633 which are interpreted as the maximum (goal) and the minimum line length,
6634 respectively, in a spirit rather equal to the
6636 program, but line-, not paragraph-based.
6637 If not set explicitly the minimum will reflect the goal algorithmically.
6638 The goal can't be smaller than the length of
6640 plus some additional pad.
6641 Necessary adjustments take place silently.
6645 If defined, gives the pathname of the folder used to record all outgoing
6647 If not defined, then outgoing mail is not saved.
6648 When saving to this folder fails the message is not sent,
6649 but instead saved to
6653 .It Va reply_strings
6654 Can be set to a comma-separated list of (case-insensitive according to
6655 ASCII rules) strings which shall be recognized in addition to the
6658 reply message indicators \(en builtin are
6660 which is mandated by RFC 5322, as well as the german
6665 A list of addresses to put into the
6667 field of the message header.
6668 Members of this list are handled as if they were in the
6673 .It Va reply-to-honour
6676 header is honoured when replying to a message via
6680 This is a quadoption; if set without a value it defaults to
6685 When \*(UA initially prints the message headers it determines the number
6686 to print by looking at the speed of the terminal.
6687 The faster the terminal, the more it prints.
6688 This option overrides this calculation and specifies how many message
6689 headers are printed.
6690 This number is also used for scrolling with the
6696 \*(OP A comma-separated list of character set names that can be used in
6697 outgoing internet mail.
6698 The value of the variable
6700 is automatically appended to this list of character-sets.
6701 If no character set conversion capabilities are compiled into \*(UA then
6702 the only supported charset is
6705 .Va sendcharsets-else-ttycharset
6706 and refer to the section
6707 .Sx "Character sets"
6708 for the complete picture of character set conversion in \*(UA.
6712 An address that is put into the
6714 field of outgoing messages, quoting RFC 5322: the mailbox of the agent
6715 responsible for the actual transmission of the message.
6716 This field should normally not be used unless the
6718 field contains more than one address, on which case it is required.
6721 address is handled as if it were in the
6727 To use an alternate mail transport agent (MTA),
6728 set this option to the full pathname of the program to use.
6729 It may be necessary to set
6730 .Va sendmail-progname
6733 The MTA will be passed command line arguments from several possible
6734 sources: from the variable
6735 .Va sendmail-arguments
6736 if set, from the command line if given and the variable
6739 Argument processing of the MTA will always be terminated with a
6743 The otherwise occurring implicit usage of the following MTA command line
6744 arguments can be disabled by setting the binary option
6745 .Va sendmail-no-default-arguments :
6747 (for not treating a line with only a dot
6749 character as the end of input),
6757 option is set); in conjunction with the
6759 command line option \*(UA will also pass
6765 .It Va sendmail-arguments
6766 Arguments to pass through to the Mail-Transfer-Agent can be given via
6768 The content of this variable will be split up in a vector of arguments
6769 which will be joined onto other possible MTA options:
6771 .Dl set sendmail-arguments='-t -X \&"/tmp/my log\&"'
6774 .It Va sendmail-no-default-arguments
6775 \*(BY Unless this option is set \*(UA will pass some well known
6776 standard command line options to the defined
6778 program, see there for more.
6781 .It Va sendmail-progname
6782 Many systems use a so-called
6784 environment to ensure compatibility with
6786 This works by inspecting the name that was used to invoke the mail
6788 If this variable is set then the mailwrapper (the program that is
6789 actually executed when calling
6791 will treat its contents as that name.
6797 A string for use with the
6803 A string for use with the
6809 Must correspond to the name of a readable file if set.
6810 The file's content is then appended to each singlepart message
6811 and to the first part of each multipart message.
6812 Be warned that there is no possibility to edit the signature for an
6817 \*(OP Specifies a directory with CA certificates in PEM (Privacy
6818 Enhanced Mail) format for verification of S/MIME signed messages.
6821 .It Va smime-ca-file
6822 \*(OP Specifies a file with CA certificates in PEM format for
6823 verification of S/MIME signed messages.
6826 .It Va smime-cipher-USER@HOST , smime-cipher
6827 \*(OP Specifies the cipher to use when generating S/MIME encrypted
6828 messages (for the specified account).
6829 RFC 5751 mandates a default of
6832 Possible values are (case-insensitive and) in decreasing cipher strength:
6840 (DES EDE3 CBC, 168 bits; default if
6842 isn't available) and
6846 The actually available cipher algorithms depend on the cryptographic
6847 library that \*(UA uses.
6848 \*(OP Support for more cipher algorithms may be available through
6849 dynamic loading via, e.g.,
6850 .Xr EVP_get_cipherbyname 3
6851 (OpenSSL) if \*(UA has been compiled to support this.
6854 .It Va smime-crl-dir
6855 \*(OP Specifies a directory that contains files with CRLs in PEM format
6856 to use when verifying S/MIME messages.
6859 .It Va smime-crl-file
6860 \*(OP Specifies a file that contains a CRL in PEM format to use when
6861 verifying S/MIME messages.
6864 .It Va smime-encrypt-USER@HOST
6865 \*(OP If this variable is set, messages send to the given receiver are
6866 encrypted before sending.
6867 The value of the variable must be set to the name of a file that
6868 contains a certificate in PEM format.
6870 If a message is sent to multiple recipients,
6871 each of them for whom a corresponding variable is set will receive an
6872 individually encrypted message;
6873 other recipients will continue to receive the message in plain text
6875 .Va smime-force-encryption
6877 It is recommended to sign encrypted messages, i.e., to also set the
6881 .Mx Va smime-sign-cert
6882 .It Va smime-sign-cert-USER@HOST , smime-sign-cert
6883 \*(OP Points to a file in PEM format.
6884 For the purpose of signing and decryption this file needs to contain the
6885 user's private key as well as his certificate.
6889 is always derived from the value of
6891 (or, if that contains multiple addresses,
6893 For the purpose of encryption the recipient's public encryption key
6894 (certificate) is expected; the command
6896 can be used to save certificates of signed messages (the section
6897 .Sx "Signed and encrypted messages with S/MIME"
6898 gives some details).
6899 This mode of operation is usually driven by the specialized form.
6901 When decrypting messages the account is derived from the recipient
6906 of the message, which are searched for addresses for which such
6908 \*(UA always uses the first address that matches,
6909 so if the same message is sent to more than one of the user's addresses
6910 using different encryption keys, decryption might fail.
6912 .Mx Va smime-sign-include-certs
6913 .It Va smime-sign-include-certs-USER@HOST , smime-sign-include-certs
6914 \*(OP If used, this is supposed to a consist of a comma-separated list
6915 of files, each of which containing a single certificate in PEM format to
6916 be included in the S/MIME message in addition to the
6919 This is most useful for long certificate chains if it is desired to aid
6920 the receiving party's verification process.
6921 Note that top level certificates may also be included in the chain but
6922 don't play a role for verification.
6924 .Va smime-sign-cert .
6925 Remember that for this
6927 refers to the variable
6929 (or, if that contains multiple addresses,
6932 .Mx Va smime-sign-message-digest
6933 .It Va smime-sign-message-digest-USER@HOST , smime-sign-message-digest
6934 \*(OP Specifies the message digest to use when signing S/MIME messages.
6935 RFC 5751 mandates a default of
6937 Possible values are (case-insensitive and) in decreasing cipher strength:
6945 The actually available message digest algorithms depend on the
6946 cryptographic library that \*(UA uses.
6947 \*(OP Support for more message digest algorithms may be available
6948 through dynamic loading via, e.g.,
6949 .Xr EVP_get_digestbyname 3
6950 (OpenSSL) if \*(UA has been compiled to support this.
6951 Remember that for this
6953 refers to the variable
6955 (or, if that contains multiple addresses,
6960 \*(OP Normally \*(UA invokes the program defined via
6962 to transfer messages, as described in
6963 .Sx "Sending mail" .
6966 variable will instead cause SMTP network connections be made to the
6967 server specified therein in order to directly submit the message.
6968 \*(UA knows about three different
6969 .Dq SMTP protocols :
6971 .Bl -bullet -compact
6973 The plain SMTP protocol (RFC 5321) that normally lives on the
6974 server port 25 and requires setting the
6975 .Va smtp-use-starttls
6976 variable to enter a SSL/TLS encrypted session state.
6977 Assign a value like \*(IN
6978 .Ql [smtp://][user[:password]@]server[:port]
6980 .Ql [smtp://]server[:port] )
6981 to choose this protocol.
6983 Then the so-called SMTPS which is supposed to live on server port 465
6984 and is automatically SSL/TLS secured.
6985 Unfortunately it never became a standardized protocol and may thus not
6986 be supported by your hosts network service database
6987 \(en in fact the port number has already been reassigned to other
6990 SMTPS is nonetheless a commonly offered protocol and thus can be
6991 chosen by assigning a value like \*(IN
6992 .Ql smtps://[user[:password]@]server[:port]
6994 .Ql smtps://server[:port] ) ;
6995 due to the mentioned problems it is usually necessary to explicitly
7000 Finally there is the SUBMISSION protocol (RFC 6409), which usually
7001 lives on server port 587 and is practically identically to the SMTP
7002 protocol from \*(UAs point of view beside that; it requires setting the
7003 .Va smtp-use-starttls
7004 variable to enter a SSL/TLS secured session state.
7005 Assign a value like \*(IN
7006 .Ql submission://[user[:password]@]server[:port]
7008 .Ql submission://server[:port] ) .
7011 For more on credentials etc. please see
7012 .Sx "On URL syntax and credential lookup" .
7013 The SMTP transfer is executed in a child process, which runs
7014 asynchronously unless either the
7019 If it receives a TERM signal, it will abort and save the message to
7023 .It Va smtp-auth-USER@HOST , smtp-auth-HOST , smtp-auth
7024 \*(OP Variable chain that sets the SMTP authentication method.
7031 as well as the \*(OPal methods
7037 method doesn't need any user credentials,
7039 requires a user name and all other methods require a user name and
7047 .Va smtp-auth-password
7049 .Va smtp-auth-user ) .
7054 .Va smtp-auth-USER@HOST :
7055 may override dependend on sender address in the variable
7058 .It Va smtp-auth-password
7059 \*(OP \*(OU Sets the global fallback password for SMTP authentication.
7060 If the authentication method requires a password, but neither
7061 .Va smtp-auth-password
7063 .Va smtp-auth-password-USER@HOST
7065 \*(UA will ask for a password on the user's terminal.
7067 .It Va smtp-auth-password-USER@HOST
7069 .Va smtp-auth-password
7070 for specific values of sender addresses, dependent upon the variable
7073 .It Va smtp-auth-user
7074 \*(OP \*(OU Sets the global fallback user name for SMTP authentication.
7075 If the authentication method requires a user name, but neither
7078 .Va smtp-auth-user-USER@HOST
7080 \*(UA will ask for a user name on the user's terminal.
7082 .It Va smtp-auth-user-USER@HOST
7085 for specific values of sender addresses, dependent upon the variable
7089 .It Va smtp-hostname
7090 \*(IN Normally \*(UA uses the variable
7092 to derive the necessary
7094 information to issue a
7099 can be used to use the
7101 from the SMTP account
7108 from the content of this variable (or, if that is the empty string,
7110 or the local hostname as a last resort).
7111 This often allows using an address that is itself valid but hosted by
7112 a provider other than which (in
7114 is about to send the message.
7115 Setting this variable also influences the generated
7120 .It Va spam-interface
7121 \*(OP In order to use any of the spam-related commands (like, e.g.,
7123 the desired spam interface must be defined by setting this variable.
7124 Please refer to the manual section
7126 for the complete picture of spam handling in \*(UA.
7127 All or none of the following interfaces may be available:
7129 .Bl -tag -width ".It Ql _ilte_"
7135 .Pf ( Lk http://spamassassin.apache.org SpamAssassin )
7137 Different to the generic filter interface \*(UA will automatically add
7138 the correct arguments for a given command and has the necessary
7139 knowledge to parse the program's output.
7142 will have been compiled into the \*(UA binary if
7147 Shall it be necessary to define a specific connection type (rather than
7148 using a configuration file for that), the variable
7150 can be used as in, e.g.,
7151 .Ql -d server.example.com -p 783 .
7152 It is also possible to specify a per-user configuration via
7154 Note that this interface doesn't inspect the
7156 flag of a message for the command
7160 \*(UA will directly communicate with the
7166 stream socket as specified in
7168 It is possible to specify a per-user configuration via
7172 generic spam filter support via freely configurable hooks.
7173 This interface is ment for programs like
7177 and requires according behaviour in respect to the hooks' exit
7178 status for at least the command
7181 meaning a message is spam,
7185 for unsure and any other return value indicating a hard error);
7186 since the hooks can include shell code snippets diverting behaviour
7187 can be intercepted as necessary.
7189 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
7192 .Va spamfilter-spam ;
7195 contains examples for some programs.
7196 The process environment of the hooks will have the variables
7197 .Ev NAIL_TMPDIR , TMPDIR
7199 .Ev NAIL_FILENAME_GENERATED
7201 Note that spam score support for
7203 isn't supported unless the \*(OPtional regular expression support is
7205 .Va spamfilter-rate-scanscore
7212 \*(OP Messages that exceed this size won't be passed through to the
7214 .Va spam-interface .
7215 The default is 420000 bytes.
7218 .It Va spamc-command
7219 \*(OP The path to the
7223 .Va spam-interface .
7224 Note that the path is not expanded, but used
7226 A fallback path will have been compiled into the \*(UA binary if the
7227 executable had been found during compilation.
7230 .It Va spamc-arguments
7231 \*(OP Even though \*(UA deals with most arguments for the
7234 automatically, it may at least sometimes be desirable to specifiy
7235 connection-related ones via this variable, e.g.,
7236 .Ql -d server.example.com -p 783 .
7240 \*(OP Specify a username for per-user configuration files for the
7242 .Va spam-interface .
7243 If this is set to the empty string then \*(UA will use the name of the
7249 \*(OP Specify the path of the
7251 domain socket on which
7253 listens for connections for the
7255 .Va spam-interface .
7256 Note that the path is not expanded, but used
7261 \*(OP Specify a username for per-user configuration files for the
7263 .Va spam-interface .
7264 If this is set to the empty string then \*(UA will use the name of the
7273 .It Va spamfilter-ham , spamfilter-noham , \
7274 spamfilter-nospam , spamfilter-rate , spamfilter-spam
7275 \*(OP Command and argument hooks for the
7277 .Va spam-interface .
7280 contains examples for some programs.
7283 .It Va spamfilter-rate-scanscore
7284 \*(OP Because of the generic nature of the
7287 spam scores are not supported for it by default, but if the \*(OPtional
7288 regular expression support is available then setting this variable can
7289 be used to overcome this restriction.
7290 It is interpreted as follows: first a number (digits) is parsed that
7291 must be followed by a semicolon
7293 and a regular expression.
7294 Then the latter is used to parse the first output line of the
7296 hook, and, in case the evaluation is successful, the group that has been
7297 specified via the number is interpreted as a floating point scan score.
7301 \*(OP Specifies a directory with CA certificates in PEM (Pricacy
7302 Enhanced Mail) for verification of of SSL/TLS server certificates.
7304 .Xr SSL_CTX_load_verify_locations 3
7305 for more information.
7309 \*(OP Specifies a file with CA certificates in PEM format for
7310 verification of SSL/TLS server certificates.
7312 .Xr SSL_CTX_load_verify_locations 3
7313 for more information.
7316 .It Va ssl-cert-USER@HOST , ssl-cert-HOST , ssl-cert
7317 \*(OP Variable chain that sets the file name for a SSL/TLS client
7318 certificate required by some servers.
7319 This is a direct interface to the
7323 function of the OpenSSL library, if available.
7325 .Mx Va ssl-cipher-list
7326 .It Va ssl-cipher-list-USER@HOST , ssl-cipher-list-HOST , ssl-cipher-list
7327 \*(OP Specifies a list of ciphers for SSL/TLS connections.
7328 This is a direct interface to the
7332 function of the OpenSSL library, if available; see
7334 for more information.
7335 By default \*(UA doesn't set a list of ciphers, which in effect will use a
7337 specific cipher (protocol standards ship with a list of acceptable
7338 ciphers), possibly cramped to what the actually used SSL/TLS library
7339 supports \(en the manual section
7340 .Sx "An example configuration"
7341 also contains a SSL/TLS use case.
7344 .It Va ssl-config-file
7345 \*(OP If this variable is set \*(UA will call
7346 .Xr CONF_modules_load_file 3
7347 to allow OpenSSL to be configured according to the host system wide
7349 If a non-empty value is given then this will be used to specify the
7350 configuration file to be used instead of the global OpenSSL default;
7351 note that in this case it is an error if the file cannot be loaded.
7352 The application name will always be passed as
7357 \*(OP Specifies a file that contains a CRL in PEM format to use when
7358 verifying SSL/TLS server certificates.
7362 \*(OP Specifies a directory that contains files with CRLs in PEM format
7363 to use when verifying SSL/TLS server certificates.
7366 .It Va ssl-key-USER@HOST , ssl-key-HOST , ssl-key
7367 \*(OP Variable chain that sets the file name for the private key of
7368 a SSL/TLS client certificate.
7369 If unset, the name of the certificate file is used.
7370 The file is expected to be in PEM format.
7371 This is a direct interface to the
7375 function of the OpenSSL library, if available.
7378 .It Va ssl-method-USER@HOST , ssl-method-HOST , ssl-method
7380 \*(OB Please use the newer and more flexible
7382 instead: if both values are set,
7384 will take precedence!
7385 Can be set to the following values, the actually used
7387 specification to which it is mapped is shown in parenthesis:
7389 .Pf ( Ql -ALL, TLSv1.2 ) ,
7391 .Pf ( Ql -ALL, TLSv1.1 ) ,
7393 .Pf ( Ql -ALL, TLSv1 )
7396 .Pf ( Ql -ALL, SSLv3 ) ;
7401 and thus includes the SSLv3 protocol.
7402 Note that SSLv2 is no longer supported at all.
7405 .It Va ssl-protocol-USER@HOST , ssl-protocol-HOST , ssl-protocol
7406 \*(OP Specify the used SSL/TLS protocol.
7407 This is a direct interface to the
7411 function of the OpenSSL library, if available;
7412 otherwise an \*(UA internal parser is used which understands the
7413 following subset of (case-insensitive) command strings:
7419 as well as the special value
7421 Multiple specifications may be given via a comma-separated list which
7422 ignores any whitespace.
7425 plus prefix will enable a protocol, a
7427 minus prefix will disable it, so that
7429 will enable only the TLSv1.2 protocol.
7431 It depends upon the used TLS/SSL library which protocols are actually
7432 supported and which protocols are used if
7434 is not set, but note that SSLv2 is no longer supported at all and
7436 Especially for older protocols explicitly securing
7438 may be worthwile, see
7439 .Sx "An example configuration" .
7443 \*(OP Gives the pathname to an entropy daemon socket, see
7445 Not all SSL/TLS libraries support this.
7448 .It Va ssl-rand-file
7449 \*(OP Gives the pathname to a file with entropy data, see
7450 .Xr RAND_load_file 3 .
7451 If the file is a regular file writable by the invoking user,
7452 new data is written to it after it has been loaded.
7455 .It Va ssl-verify-USER@HOST , ssl-verify-HOST , ssl-verify
7456 \*(OP Variable chain that sets the action to be performed if an error
7457 occurs during SSL/TLS server certificate validation.
7458 Valid (case-insensitive) values are
7460 (fail and close connection immediately),
7462 (ask whether to continue on standard input),
7464 (print a warning and continue),
7466 (do not perform validation).
7472 If only set without an assigned value, then this option inhibits the
7477 header fields that include obvious references to \*(UA.
7478 There are two pitfalls associated with this:
7479 First, the message id of outgoing messages is not known anymore.
7480 Second, an expert may still use the remaining information in the header
7481 to track down the originating mail user agent.
7486 suppression doesn't occur.
7490 If defined, gives the number of lines of a message to be printed out
7491 with the top command; normally, the first five lines are printed.
7495 The character set of the terminal \*(UA operates on,
7496 and the one and only supported character set that \*(UA can use if no
7497 character set conversion capabilities have been compiled into it,
7498 in which case it defaults to ISO-8859-1 unless it can deduce a value
7502 Refer to the section
7503 .Sx "Character sets"
7504 for the complete picture about character sets.
7507 .It Va user-HOST , user
7508 \*(IN Variable chain that sets a global fallback user name, which is
7509 used in case none has been given in the protocol and account-specific
7511 This variable defaults to the value of
7518 .It Va version , version-major , version-minor , version-update
7519 \*(RO \*(UA version information: the first variable contains a string
7520 containing the complete version identification \(en this is identical to
7521 the output of the command
7523 The latter three contain only digits: the major, minor and update
7527 .\" }}} (Variable options)
7530 .\" .Sh ENVIRONMENT {{{
7534 .Dq environment variable
7535 should be considered an indication that the following variables are
7536 either standardized as being vivid parts of process environments, or
7537 are commonly found in there.
7538 Unless otherwise explicitly noted they integrate into the normal
7539 variable handling, as documented above, from \*(UAs point of view.
7541 .Bl -tag -width ".It Ev _AILR_"
7544 The user's preferred width in column positions for the terminal screen
7546 Queried and used once on program startup.
7550 The name of the file to use for saving aborted messages if
7552 is set; this defaults to
7560 Pathname of the text editor to use in the
7564 .Sx "TILDE ESCAPES" .
7565 A default editor is used if this value is not defined.
7569 The user's home directory.
7570 This variable is only used when it resides in the process environment.
7573 to update the value at runtime.
7580 .It Ev LANG , LC_ALL , LC_COLLATE , LC_CTYPE , LC_MESSAGES
7584 .Sx "Character sets" .
7588 The user's preferred number of lines on a page or the vertical screen
7589 or window size in lines.
7590 Queried and used once on program startup.
7594 Pathname of the directory lister to use in the
7596 command when operating on local mailboxes.
7599 (path search through
7604 The name of the user's mbox file.
7605 Supports a logical subset of the special conventions that are
7611 The fallback default is
7619 Is used as a startup file instead of
7622 When \*(UA scripts are invoked on behalf of other users,
7623 this variable should be set to
7625 to avoid side-effects from reading their configuration files.
7626 This variable is only used when it resides in the process environment.
7629 .It Ev NAIL_NO_SYSTEM_RC
7630 If this variable is set then reading of
7632 at startup is inhibited, i.e., the same effect is achieved as if \*(UA
7633 had been started up with the option
7635 This variable is only used when it resides in the process environment.
7639 \*(IN \*(OP This variable overrides the default location of the user's
7645 Pathname of the program to use in the more command or when the
7648 The default paginator is
7650 (path search through
7655 A list of directories that is searched by the shell when looking for
7656 commands (as such only recognized in the process environment).
7660 The shell to use for the commands
7666 and when starting subprocesses.
7667 A default shell is used if this option is not defined.
7671 Changes the letters printed in the first column of a header summary.
7675 \*(OP The terminal type for which output is to be prepared.
7679 Used as directory for temporary files instead of
7682 This variable is only used when it resides in the process environment.
7685 to update the value at runtime.
7689 Force identification as the given user, i.e., identical to the
7691 command line option.
7692 This variable is only used when it resides in the process environment.
7695 to update the value at runtime, but note that doing so won't trigger any
7696 of those validation checks that were performed on program startup (again).
7700 Pathname of the text editor to use in the
7704 .Sx "TILDE ESCAPES" .
7712 .Bl -tag -width ".It Pa _etc/mime.type_"
7714 File giving initial commands.
7717 System wide initialization file.
7720 .It Pa ~/.mime.types
7721 Personal MIME types, see
7722 .Sx "The mime.types files" .
7725 .It Pa /etc/mime.types
7726 System wide MIME types, see
7727 .Sx "The mime.types files" .
7731 \*(IN \*(OP The default location of the users
7733 file \(en the section
7734 .Sx "The .netrc file"
7735 documents the file format.
7738 .\" .Ss "The mime.types files" {{{
7739 .Ss "The mime.types files"
7741 When sending messages \*(UA tries to determine the content type of all
7743 When displaying message content or attachments \*(UA uses the content
7744 type to decide wether it can directly display data or wether it needs to
7745 deal with content handlers, as can be defined via
7746 .Va pipe-TYPE/SUBTYPE
7748 .Va pipe-EXTENSION )
7749 variables, to do so.
7752 It learns about MIME types and how to treat them by reading
7754 files, the loading of which can be controlled by setting the variable
7755 .Va mimetypes-load-control .
7758 can also be used to deal with MIME types.)
7760 files have the following syntax:
7763 .Dl type/subtype extension [extension ...]
7768 are strings describing the file contents, and one or multiple
7770 s, separated by whitespace, name the part of a filename starting after
7771 the last dot (of interest).
7772 Comments may be introduced anywhere on a line with a number sign
7774 causing the remaining line to be discarded.
7776 \*(UA also supports an extended, non-portable syntax in specially
7777 crafted files, which can be loaded via the alternative value syntax of
7778 .Va mimetypes-load-control
7779 and prepends an optional
7783 .Dl [type-marker ]type/subtype extension [extension ...]
7786 The following type markers are supported:
7789 .Bl -tag -compact -offset indent -width ".It Ar _n_u"
7791 Treat message parts with this content as plain text.
7796 Treat message parts with this content as HTML tagsoup.
7797 If the \*(OPal HTML-tagsoup-to-text converter is not available treat
7798 the content as plain text instead.
7802 but instead of falling back to plain text require an explicit content
7803 handler to be defined.
7808 for sending messages:
7809 .Va mime-allow-text-controls .
7810 For reading etc. messages:
7811 .Sx "Viewing HTML mail and MIME attachments" ,
7812 .Va mime-counter-evidence ,
7813 .Va pipe-TYPE/SUBTYPE ,
7814 .Va pipe-EXTENSION .
7817 .\" .Ss "The .netrc file" {{{
7818 .Ss "The .netrc file"
7822 file contains user credentials for machine accounts.
7823 The default location in the user's
7825 directory may be overridden by the
7827 environment variable.
7828 The file consists of space, tabulator or newline separated tokens.
7829 \*(UA implements a parser that supports a superset of the original BSD
7830 syntax, but users should nonetheless be aware of portability glitches
7831 of that file format, shall their
7833 be usable across multiple programs and platforms:
7836 .Bl -bullet -compact
7838 BSD doesn't support single, but only double quotation marks, e.g.,
7839 .Ql password="pass with spaces" .
7841 BSD (only?) supports escaping of single characters via a backslash
7842 (e.g., a space can be escaped via
7844 in- as well as outside of a quoted string.
7846 BSD doesn't require the final quotation mark of the final user input token.
7848 At least Hewlett-Packard seems to support a format which also allows
7849 tokens to be separated with commas \(en this format is not supported!
7851 Whereas other programs may require that the
7853 file is accessible by only the user if it contains a
7859 \*(UA will always require these strict permissions.
7863 Of the following list of supported tokens \*(UA only uses (and caches)
7869 .Bl -tag -width password
7870 .It Cd machine Ar name
7871 The hostname of the entries' machine, lowercase-normalized by \*(UA
7873 Any further file content, until either end-of-file or the occurrence
7878 first-class token is bound (only related) to the machine
7881 As an extension that shouldn't be the cause of any worries
7882 \*(UA supports a single wildcard prefix for
7884 .Bd -literal -offset indent
7885 machine *.example.com login USER password PASS
7886 machine pop3.example.com login USER password PASS
7887 machine smtp.example.com login USER password PASS
7893 .Ql pop3.example.com ,
7897 .Ql local.smtp.example.com .
7898 Note that in the example neither
7899 .Ql pop3.example.com
7901 .Ql smtp.example.com
7902 will be matched by the wildcard, since the exact matches take
7903 precedence (it is however faster to specify it the other way around).
7908 except that it is a fallback entry that is used shall none of the
7909 specified machines match; only one default token may be specified,
7910 and it must be the last first-class token.
7912 .It Cd login Ar name
7913 The user name on the remote machine.
7915 .It Cd password Ar string
7916 The user's password on the remote machine.
7918 .It Cd account Ar string
7919 Supply an additional account password.
7920 This is merely for FTP purposes.
7922 .It Cd macdef Ar name
7924 A macro is defined with the specified
7926 it is formed from all lines beginning with the next line and continuing
7927 until a blank line is (consecutive newline characters are) encountered.
7930 entries cannot be utilized by multiple machines, too, but must be
7931 defined following the
7933 they are intended to be used with.)
7936 exists, it is automatically run as the last step of the login process.
7937 This is merely for FTP purposes.
7944 .\" .Sh EXAMPLES {{{
7947 .\" .Ss "An example configuration" {{{
7948 .Ss "An example configuration"
7950 .Bd -literal -offset indent
7951 # This example assumes v15.0 compatibility mode
7954 # Where are the up-to-date SSL certificates?
7955 #set ssl-ca-dir=/etc/ssl/certs
7956 set ssl-ca-file=/etc/ssl/certs/ca-certificates.crt
7958 # (Since we manage up-to-date ones explicitly, don't use any,
7959 # possibly outdated, default certificates shipped with OpenSSL
7960 set ssl-no-default-ca
7962 # Don't use protocols olders than TLS v1.2.
7963 # Change this only when the remote server doesn't support it:
7964 # maybe use ssl-protocol-HOST (or -USER@HOST) syntax to define
7965 # such explicit exceptions, then
7966 set ssl-protocol="-ALL,+TLSv1.2"
7968 # Explicitly define the list of ciphers, which may improve security,
7969 # especially with protocols older than TLS v1.2. See ciphers(1).
7970 # Hint: it is important to include "@STRENGTH": only with it the
7971 # final list will be sorted by algorithm strength.
7972 # This is an example: in reality it is possibly best to only use
7973 # ssl-cipher-list-HOST (or -USER@HOST), as necessary, again..
7974 set ssl-cipher-list="ALL:!aNULL:!MEDIUM:!LOW:\e
7975 !MD5:!RC4:!EXPORT:@STRENGTH"
7977 # Request strict transport security checks!
7978 set ssl-verify=strict
7980 # Essential setting: select allowed character sets
7981 set sendcharsets=utf-8,iso-8859-1
7983 # A very kind option: when replying to a message, first try to
7984 # use the same encoding that the original poster used herself!
7985 set reply-in-same-charset
7987 # When replying to or forwarding a message the comment and name
7988 # parts of email addresses are removed unless this variable is set
7991 # When sending messages, wait until the Mail-Transfer-Agent finishs.
7992 # Only like this you'll be able to see errors reported through the
7993 # exit status of the MTA (including the builtin SMTP one)!
7996 # Only use builtin MIME types, no mime.types(5) files
7997 set mimetypes-load-control
7999 # Default directory where we act in (relative to $HOME)
8000 set folder=mail MBOX=+mbox.mbox record=+sent.mbox \e
8003 # Make "file mymbox" and "file myrec" go to..
8004 shortcut mymbox %:+mbox.mbox myrec +sent.mbox
8006 # Not really optional, e.g., for S/MIME
8007 set from="Your Name <youremail@domain>"
8009 # It may be necessary to set hostname and/or smtp-hostname
8010 # if the "SERVER" of smtp and "domain" of from don't match.
8011 # The `urlencode' command can be used to encode USER and PASS
8012 set smtp=(smtp[s]/submission)://[USER[:PASS]@]SERVER[:PORT] \e
8013 smtp-auth=login/plain... \e
8016 # Never refuse to start into interactive mode, and more
8018 colour-pager crt= followup-to followup-to-honour=ask-yes \e
8019 history-gabby mime-counter-evidence=6 \e
8020 prompt="\e033[31m?\e?[\e$ \e@]\e& \e033[0m" \e
8021 NAIL_HISTFILE=+.s-nailhist NAIL_HISTSIZE=-1 \e
8022 reply-to-honour=ask-yes
8024 # When `p'rinting messages, show only these headers
8025 # (use `P'rint for all headers and `S'how for raw message)
8026 retain date from to cc subject
8028 # Some mailing lists
8029 mlist @xyz-editor.xyz$ @xyzf.xyz$
8030 mlsubscribe ^xfans@xfans.xyz$
8032 # A real life example of a very huge free mail provider
8035 set from="Your Name <youremail@domain>"
8036 # (The plain smtp:// proto is optional)
8037 set smtp=USER:PASS@smtp.gmXil.com smtp-use-starttls
8040 # Here is a pretty large one which does not allow sending mails
8041 # if there is a domain name mismatch on the SMTP protocol level,
8042 # which would bite us if the value of from does not match, e.g.,
8043 # for people who have a sXXXXeforge project and want to speak
8044 # with the mailing list under their project account (in from),
8045 # still sending the message through their normal mail provider
8048 set from="Your Name <youremail@domain>"
8049 set smtp=smtps://USER:PASS@smtp.yaXXex.ru:465 \e
8050 hostname=yaXXex.com smtp-hostname=
8053 # Create some new commands so that, e.g., `ls /tmp' will..
8064 ghost llS !ls -aFlrS
8067 # We don't support gpg(1) directly yet. But simple --clearsign'd
8068 # message parts can be dealt with as follows:
8071 set pipe-text/plain="set -C;\e
8072 : > \e"${TMPDIR}/${NAIL_FILENAME_GENERATED}\e" \e
8073 trap \e"rm -f \e\e\e"${TMPDIR}/${NAIL_FILENAME_GENERATED}\e\e\e"\e" \e
8074 EXIT INT QUIT PIPE TERM;\e
8076 cat > \e"${TMPDIR}/${NAIL_FILENAME_GENERATED}\e";\e
8077 < \e"${TMPDIR}/${NAIL_FILENAME_GENERATED}\e" awk \e
8078 -v TMPFILE=\e"${TMPDIR}/${NAIL_FILENAME_GENERATED}\e" '\e
8080 /^-----BEGIN PGP SIGNED MESSAGE-----/,/^$/ {\e
8083 print \e"--- GPG --verify ---\e";\e
8084 system(\e"gpg --verify \e" TMPFILE \e" 2>&1\e");\e
8085 print \e"--- GPG --verify ---\e";\e
8089 /^-----BEGIN PGP SIGNATURE-----/,\e
8090 /^-----END PGP SIGNATURE-----/ {\e
8100 !printf 'Key IDs to gpg --recv-keys: ';\e
8102 gpg --recv-keys ${keyids};
8108 When storing passwords in
8110 appropriate permissions should be set on this file with
8111 .Ql $ chmod 0600 \*(ur .
8114 is available user credentials can be stored in the central
8116 file instead; e.g., here is a different version of the example account
8117 that sets up SMTP and POP3:
8119 .Bd -literal -offset indent
8122 set from="Your Name <youremail@domain>"
8124 #set agent-shell-lookup="gpg -d .pass.gpg"
8126 set smtp=smtps://smtp.yXXXXx.ru:465 \e
8127 smtp-hostname= hostname=yXXXXx.com
8128 set pop3-keepalive=240 pop3-no-apop-pop.yXXXXx.ru
8129 ghost xp fi pop3s://pop.yXXXXx.ru
8138 .Bd -literal -offset indent
8139 machine *.yXXXXx.ru login USER password PASS
8144 .Va agent-shell-lookup
8145 is available things could be diversified further by using encrypted
8146 password storage: for this, don't specify
8150 file and instead uncomment the line that defines agent lookup in the
8153 above, then create the encrypted password storage file
8156 .Bd -literal -offset indent
8159 $ eval `gpg-agent --daemon \e
8160 --pinentry-program=/usr/bin/pinentry-curses \e
8161 --max-cache-ttl 99999 --default-cache-ttl 99999`
8165 This configuration should now work just fine (use the
8167 command line option for a(n almost) dry-run):
8170 .Dl $ echo text | \*(ua -vv -AXandeX -s Subject some@where
8173 .\" .Ss "Signed and encrypted messages with S/MIME" {{{
8174 .Ss "Signed and encrypted messages with S/MIME"
8176 \*(OP S/MIME provides two central mechanisms:
8177 message signing and message encryption.
8178 A signed message contains some data in addition to the regular text.
8179 The data can be used to verify that the message was sent using a valid
8180 certificate, that the sender's address in the message header matches
8181 that in the certificate, and that the message text has not been altered.
8182 Signing a message does not change its regular text;
8183 it can be read regardless of whether the recipient's software is able to
8187 It is thus usually possible to sign all outgoing messages if so desired.
8188 Encryption, in contrast, makes the message text invisible for all people
8189 except those who have access to the secret decryption key.
8190 To encrypt a message, the specific recipient's public encryption key
8192 It is therefore not possible to send encrypted mail to people unless their
8193 key has been retrieved from either previous communication or public key
8195 A message should always be signed before it is encrypted.
8196 Otherwise, it is still possible that the encrypted message text is
8200 A central concept to S/MIME is that of the certification authority (CA).
8201 A CA is a trusted institution that issues certificates.
8202 For each of these certificates it can be verified that it really
8203 originates from the CA, provided that the CA's own certificate is
8205 A set of CA certificates is usually delivered with OpenSSL and installed
8207 If you trust the source of your OpenSSL software installation,
8208 this offers reasonable security for S/MIME on the Internet.
8210 .Va ssl-no-default-ca
8214 .Va smime-ca-dir . )
8215 In general, a certificate cannot be more secure than the method its CA
8216 certificate has been retrieved with, though.
8217 Thus if you download a CA certificate from the Internet,
8218 you can only trust the messages you verify using that certificate as
8219 much as you trust the download process.
8222 The first thing you need for participating in S/MIME message exchange is
8223 your personal certificate, including a private key.
8224 The certificate contains public information, in particular your name and
8225 your email address(es), and the public key that is used by others to
8226 encrypt messages for you,
8227 and to verify signed messages they supposedly received from you.
8228 The certificate is included in each signed message you send.
8229 The private key must be kept secret.
8230 It is used to decrypt messages that were previously encrypted with your
8231 public key, and to sign messages.
8234 For personal use it is recommended that you get a S/MIME certificate
8235 from one of the major CAs on the Internet using your WWW browser.
8236 Many CAs offer such certificates for free.
8238 .Lk https://www.CAcert.org
8239 which issues client and server certificates to members of their
8240 community for free; their root certificate
8241 .Pf ( Lk https://\:www.cacert.org/\:certs/\:root.crt )
8242 is often not in the default set of trusted CA root certificates, though,
8243 which means you will have to download their root certificate separately
8244 and ensure it is part of our S/MIME certificate validation chain by
8247 or as a vivid member of the
8249 But let's take a step-by-step tour on how to setup S/MIME with
8250 a certificate from CAcert.org despite this situation!
8253 First of all you will have to become a member of the CAcert.org
8254 community, simply by registrating yourself via the web interface.
8255 Once you are, create and verify all email addresses you want to be able
8256 to create signed and encrypted messages for/with using the corresponding
8257 entries of the web interface.
8258 Now ready to create S/MIME certificates, so let's create a new
8259 .Dq client certificate ,
8260 ensure to include all email addresses that should be covered by the
8261 certificate in the following web form, and also to use your name as the
8265 Create a private key and a certificate request on your local computer
8266 (please see the manual pages of the used commands for more in-depth
8267 knowledge on what the used arguments etc. do):
8270 .Dl openssl req -nodes -newkey rsa:4096 -keyout key.pem -out creq.pem
8273 Afterwards copy-and-paste the content of
8275 into the certificate-request (CSR) field of the web form on the
8276 CAcert.org website (you may need to unfold some
8277 .Dq advanced options
8278 to see the corresponding text field).
8279 This last step will ensure that your private key (which never left your
8280 box) and the certificate belong together (through the public key that
8281 will find its way into the certificate via the certificate-request).
8282 You are now ready and can create your CAcert certified certificate.
8283 Download and store or copy-and-paste it as
8288 In order to use your new S/MIME setup you will have to create
8289 a combined private key/public key (certificate) file:
8292 .Dl cat key.pem pub.crt > ME@HERE.com.paired
8295 This is the file \*(UA will work with.
8296 If you have created your private key with a passphrase then \*(UA will
8297 ask you for it whenever a message is signed or decrypted.
8298 Set the following variables to henceforth use S/MIME (setting
8300 is of interest for verification only):
8302 .Bd -literal -offset indent
8303 set smime-ca-file=ALL-TRUSTED-ROOT-CERTS-HERE \e
8304 smime-sign-cert=ME@HERE.com.paired \e
8305 smime-sign-message-digest=SHA256 \e
8310 From each signed message you send, the recipient can fetch your
8311 certificate and use it to send encrypted mail back to you.
8312 Accordingly if somebody sends you a signed message, you can do the same,
8315 command to check the validity of the certificate.
8318 Options of interest for S/MIME signing:
8322 .Va smime-crl-file ,
8323 .Va smime-no-default-ca ,
8325 .Va smime-sign-cert ,
8326 .Va smime-sign-include-certs
8328 .Va smime-sign-message-digest .
8331 After it has been verified save the certificate via
8333 and tell \*(UA that it should use it for encryption for further
8334 communication with that somebody:
8336 .Bd -literal -offset indent
8338 set smime-encrypt-USER@HOST=FILENAME \e
8339 smime-cipher-USER@HOST=AES256
8343 Additional options of interest for S/MIME en- and decryption:
8346 .Va smime-encrypt-USER@HOST .
8349 You should carefully consider if you prefer to store encrypted messages
8351 If you do, anybody who has access to your mail folders can read them,
8352 but if you do not, you might be unable to read them yourself later if
8353 you happen to lose your private key.
8356 command saves messages in decrypted form, while the
8360 commands leave them encrypted.
8363 Note that neither S/MIME signing nor encryption applies to message
8364 subjects or other header fields yet.
8365 Thus they may not contain sensitive information for encrypted messages,
8366 and cannot be trusted even if the message content has been verified.
8367 When sending signed messages,
8368 it is recommended to repeat any important header information in the
8372 .\" .Ss "Using CRLs with S/MIME or SSL/TLS" {{{
8373 .Ss "Using CRLs with S/MIME or SSL/TLS"
8375 \*(OP Certification authorities (CAs) issue certificate revocation
8376 lists (CRLs) on a regular basis.
8377 These lists contain the serial numbers of certificates that have been
8378 declared invalid after they have been issued.
8379 Such usually happens because the private key for the certificate has
8381 because the owner of the certificate has left the organization that is
8382 mentioned in the certificate, etc.
8383 To seriously use S/MIME or SSL/TLS verification,
8384 an up-to-date CRL is required for each trusted CA.
8385 There is otherwise no method to distinguish between valid and
8386 invalidated certificates.
8387 \*(UA currently offers no mechanism to fetch CRLs, nor to access them on
8388 the Internet, so you have to retrieve them by some external mechanism.
8391 \*(UA accepts CRLs in PEM format only;
8392 CRLs in DER format must be converted, like, e.\|g.:
8395 .Dl $ openssl crl \-inform DER \-in crl.der \-out crl.pem
8398 To tell \*(UA about the CRLs, a directory that contains all CRL files
8399 (and no other files) must be created.
8404 variables, respectively, must then be set to point to that directory.
8405 After that, \*(UA requires a CRL to be present for each CA that is used
8406 to verify a certificate.
8409 .\" .Ss "Handling spam" {{{
8412 \*(OP \*(UA can make use of several spam interfaces for the purpose of
8413 identification of, and, in general, dealing with spam messages.
8414 A precondition of most commands in order to function is that the
8416 variable is set to one of the supported interfaces.
8417 Once messages have been identified as spam their (volatile)
8419 state can be prompted: the
8423 message specifications will address respective messages and their
8425 entries will be used when displaying the
8427 in the header display.
8432 rates the given messages and sets their
8435 If the spam interface offers spam scores those can also be displayed in
8436 the header display by including the
8446 will interact with the Bayesian filter of the chosen interface and learn
8447 the given messages as
8451 respectively; the last command can be used to cause
8453 of messages; it adheres to their current
8455 state and thus reverts previous teachings.
8460 will simply set and clear, respectively, the mentioned volatile
8462 message flag, without any interface interaction.
8469 .Va spam-interface Ns s
8473 require a running instance of the
8475 server in order to function, started with the option
8477 shall Bayesian filter learning be possible.
8479 only works via a local path-based
8481 socket, but otherwise the following will be equivalently fine:
8483 .Bd -literal -offset indent
8484 $ spamd -i localhost:2142 -i /tmp/.spamsock -d [-L] [-l]
8485 $ spamd --listen=localhost:2142 --listen=/tmp/.spamsock \e
8486 --daemonize [--local] [--allow-tell]
8490 Thereafter \*(UA can make use of these interfaces:
8492 .Bd -literal -offset indent
8493 $ \*(ua -Sspam-interface=spamd -Sspam-maxsize=500000 \e
8494 -Sspamd-socket=/tmp/.spamsock -Sspamd-user=
8496 $ \*(ua -Sspam-interface=spamc -Sspam-maxsize=500000 \e
8497 -Sspamc-command=/usr/local/bin/spamc \e
8498 -Sspamc-arguments="-U /tmp/.spamsock" -Sspamc-user=
8500 $ \*(ua -Sspam-interface=spamc -Sspam-maxsize=500000 \e
8501 -Sspamc-command=/usr/local/bin/spamc \e
8502 -Sspamc-arguments="-d localhost -p 2142" -Sspamc-user=
8506 Using the generic filter approach allows usage of programs like
8510 Here is an example for the former, requiring it to be accessible via
8513 .Bd -literal -offset indent
8514 $ \*(ua -Sspam-interface=filter -Sspam-maxsize=500000 \e
8515 -Sspamfilter-ham="bogofilter -n" \e
8516 -Sspamfilter-noham="bogofilter -N" \e
8517 -Sspamfilter-nospam="bogofilter -S" \e
8518 -Sspamfilter-rate="bogofilter -TTu 2>/dev/null" \e
8519 -Sspamfilter-spam="bogofilter -s" \e
8520 -Sspamfilter-rate-scanscore="1;^(.+)$"
8524 Because messages must exist on local storage in order to be scored (or
8525 used for Bayesian filter training), it is possibly a good idea to
8526 perform the local spam check last:
8528 .Bd -literal -offset indent
8529 define spamdelhook {
8531 spamset (header x-dcc-brand-metrics "bulk")
8532 # Server-side spamassassin(1)
8533 spamset (header x-spam-flag "YES")
8534 del :s # TODO we HAVE to be able to do `spamrate :u ! :sS'
8540 set folder-hook-FOLDER=spamdelhook
8544 See also the documentation for the variables
8545 .Va spam-interface , spam-maxsize ,
8546 .Va spamc-command , spamc-arguments , spamc-user ,
8547 .Va spamd-socket , spamd-user ,
8548 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
8551 .Va spamfilter-rate-scanscore .
8559 .\" .Ss "\*(UA shortly hangs on startup" {{{
8560 .Ss "\*(UA shortly hangs on startup"
8562 This can have two reasons, one is the necessity to wait for a file lock
8563 and can't be helped, the other being that \*(UA calls the function
8565 in order to query the nodename of the box (sometimes the real one is
8566 needed instead of the one represented by the internal variable
8568 You may have varying success by ensuring that the real hostname and
8572 or, more generally, that the name service is properly setup \(en
8575 return what you'd expect?
8578 .\" .Ss "I can't login to Google mail a.k.a. GMail" {{{
8579 .Ss "I can't login to Google mail a.k.a. GMail"
8581 Since 2014 some free service providers classify programs as
8583 unless they use a special authentification method (OAuth 2.0) which
8584 wasn't standardized for non-HTTP protocol authentication token query
8585 until August 2015 (RFC 7628).
8588 Different to Kerberos / GSSAPI, which is developed since the mid of the
8589 1980s, where a user can easily create a local authentication ticket for
8590 her- and himself with the locally installed
8592 program, that protocol has no such local part but instead requires
8593 a world-wide-web query to create or fetch a token; since there is no
8594 local cache this query has to be performed whenever \*(UA is invoked
8595 from the command line (in interactive sessions situation may differ).
8598 \*(UA doesn't support OAuth.
8599 Because of this it is necessary to declare \*(UA a
8601 (on the providers account web page) in order to read and send mail.
8602 However, it also seems possible to take the following steps instead:
8607 give the provider the number of a mobile phone,
8610 .Dq 2-Step Verification ,
8612 create an application specific password (16 characters), and
8614 use that special password instead of your real Google account password in
8615 S-nail (for more on that see the section
8616 .Sx "On URL syntax and credential lookup" ) .
8622 .\" .Sh "SEE ALSO" {{{
8640 .Xr spamassassin 1 ,
8667 command appeared in Version 1 AT&T Unix.
8668 Berkeley Mail was written in 1978 by Kurt Shoens.
8669 This man page is derived from from
8670 .Dq The Mail Reference Manual
8671 originally written by Kurt Shoens.
8673 enhancements are maintained and documented by Gunnar
8676 is maintained and documented by Steffen (Daode) Nurpmeso.
8679 Portions of this text are reprinted and reproduced in electronic form
8680 from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
8681 \(en Operating System Interface (POSIX), The Open Group Base
8682 Specifications Issue 6, Copyright \(co 2001-2003 by the Institute of
8683 Electrical and Electronics Engineers, Inc and The Open Group.
8684 In the event of any discrepancy between this version and the original
8685 IEEE and The Open Group Standard, the original IEEE and The Open Group
8686 Standard is the referee document.
8687 The original Standard can be obtained online at
8688 .Lk http://www.opengroup.org/unix/online.html OpenGroup.org
8689 Redistribution of this material is permitted so long as this notice
8697 .An "Christos Zoulas" ,
8698 .An "Gunnar Ritter" ,
8699 .An "Steffen Nurpmeso" Aq Mt s-nail-users@lists.sourceforge.net
8705 The character set conversion uses and relies upon the
8708 Its functionality differs widely between the various system environments
8712 Limitations with IMAP mailboxes are:
8713 It is not possible to edit messages, but it is possible to append them.
8714 Thus to edit a message, create a local copy of it, edit it, append it,
8715 and delete the original.
8716 The line count for the header display is only appropriate if the entire
8717 message has been downloaded from the server.
8718 The marking of messages as `new' is performed by the IMAP server;
8723 will not cause it to be reset, and if the
8725 variable is unset, messages that arrived during a session will not be
8726 in state `new' anymore when the folder is opened again.
8727 Also if commands queued in disconnected mode are committed,
8728 the IMAP server will delete the `new' flag for all messages in the
8730 and new messages will appear as unread when it is selected for viewing
8732 The `flagged', `answered', and `draft' attributes are usually permanent,
8733 but some IMAP servers are known to drop them without notification.
8734 Message numbers may change with IMAP every time before the prompt is
8735 printed if \*(UA is notified by the server that messages have been
8736 deleted by some other client or process.
8737 In this case, `Expunged n messages' is printed, and message numbers may
8741 Limitations with POP3 mailboxes are:
8742 It is not possible to edit messages, they can only be copied and deleted.
8743 The line count for the header display is only appropriate if the entire
8744 message has been downloaded from the server.
8745 The status field of a message is maintained by the server between
8746 connections; some servers do not update it at all, and with a server
8749 command will not cause the message status to be reset.
8754 variable have no effect.
8755 It is not possible to rename or to remove POP3 mailboxes.
8762 is typed while an IMAP or POP3 operation is in progress, \*(UA will wait
8763 until the operation can be safely aborted, and will then return to the
8764 command loop and print the prompt again.
8767 is typed while \*(UA is waiting for the operation to complete, the
8768 operation itself will be cancelled.
8769 In this case, data that has not been fetched yet will have to be fetched
8770 before the next command can be performed.
8771 If the cancelled operation was using an SSL/TLS encrypted channel,
8772 an error in the SSL transport will very likely result and render the
8773 connection unusable.
8776 As \*(UA is a mail user agent, it provides only basic SMTP services.
8777 If it fails to contact its upstream SMTP server, it will not make
8778 further attempts to transfer the message at a later time,
8779 and it does not leave other information about this condition than an
8780 error message on the terminal and an entry in
8782 This is usually not a problem if the SMTP server is located in the same
8783 local network as the computer on which \*(UA is run.
8784 However, care should be taken when using a remote server of an ISP;
8785 it might be better to set up a local SMTP server then which just acts as
8789 \*(UA immediately contacts the SMTP server (or
8791 ) even when operating in
8794 It would not make much sense for \*(UA to defer outgoing mail since SMTP
8795 servers usually provide much more elaborated delay handling than \*(UA
8796 could perform as a client.
8797 Thus the recommended setup for sending mail in
8799 mode is to configure a local SMTP server such that it sends outgoing
8800 mail as soon as an external network connection is available again,
8801 i.e., to advise it to do that from a network startup script.
8807 With IMAP, at least if the IMAP cache is used, if multiple
8811 cycles happen without an intervening change of the active mailbox then
8812 \*(UA will at some time loose the ability to keep the local state
8813 up-to-date, meaning that, e.g., messages show up with false numbers, and
8814 including the possibility that messages are accessed via numbers that
8815 are no(t longer) valid, resulting in program crashes.
8816 The solution is to change the active mailbox before that happens :).
8819 from the distribution or the repository.