1 .\"@ nail.1 - S-nail(1) reference manual.
3 .\" Copyright (c) 2000-2008 Gunnar Ritter, Freiburg i. Br., Germany.
4 .\" Copyright (c) 2012 - 2016 Steffen (Daode) Nurpmeso <steffen@sdaoden.eu>.
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34 .\"@ S-nail(1): v14.9.0-pre2 / 2016-10-31
36 .ds VV \\%v14.9.0-pre2
46 .\" If not ~/.mailrc, it breaks POSIX compatibility. And adjust main.c.
51 .ds OU [no v15-compat]
52 .ds ID [v15 behaviour may differ]
53 .ds NQ [Only new quoting rules]
64 .Nd send and receive Internet mail
70 .\" Keep in SYNC: ./nail.1:"SYNOPSIS, main()
78 .Op Fl a Ar attachment
81 .Op Fl M Ar type | Fl m Ar file | Fl q Ar file | Fl t
83 .Op Fl S Ar var Ns Op Ns = Ns Ar value
88 .Op Fl Fl \~ Ns Ar mta-option ...
97 .Op Fl S Ar var Ns Op Ns = Ns Ar value
100 .Op Fl Fl \~ Ns Ar mta-option ...
108 .Op Fl L Ar spec-list
109 .Op Fl r Ar from-addr
110 .Op Fl S Ar var Ns Op Ns = Ns Ar value
113 .Op Fl Fl \~ Ns Ar mta-option ...
118 .Mx -toc -tree html pdf ps xhtml
121 .\" .Sh DESCRIPTION {{{
124 .Bd -filled -compact -offset indent
125 .Sy Compatibility note:
126 S-nail (\*(UA) will wrap up into \%S-mailx in v15.0 (circa 2018).
127 Backward incompatibility has to be expected \(en
131 -style argument quoting rules, for example.
132 New and old behaviour is flagged \*(IN and \*(OU, and setting
135 .Sx "INTERNAL VARIABLES" ,
136 will choose new behaviour when applicable.
137 \*(OB flags what will vanish, and enabling
141 enables obsoletion warnings.
145 \*(UA is a mail processing system with a command syntax reminiscent of
147 with lines replaced by messages.
148 It is intended to provide the functionality of the POSIX
150 command, but is MIME capable and optionally offers extensions for
151 line editing, S/MIME, SMTP and POP3 among others.
153 .\" .Ss "Options" {{{
156 .Bl -tag -width ".It Fl BaNg"
159 Explicitly control which of the
161 shall be loaded: if the letter
163 is (case-insensitively) part of the
167 is loaded, likewise the letter
169 controls loading of the user's personal
171 file, whereas the letters
175 explicitly forbid loading of any resource files.
176 This option should be used by scripts: to avoid environmental noise they
179 from any configuration files and create a script-local environment,
180 explicitly setting any of the desired
181 .Sx "INTERNAL VARIABLES"
184 This option overrides
191 command for the given user email
193 after program startup is complete (all resource files are loaded, any
195 setting is being established; only
197 commands have not been evaluated yet).
198 Being a special incarnation of
200 macros for the purpose of bundling longer-lived settings, activating
201 such an email account also switches to the accounts
203 .Sx "primary system mailbox"
212 The same filename conventions as described in the section
214 apply: shell word expansion is restricted to the tilde
218 not be accessible but contain a
220 character, then anything after the
222 is assumed to specify the input character set and anything before
224 the filename: this is the only option to specify (and fixate) the input
225 character set of text attachments from the command line, not using the
227 command of and in the compose mode that follows
229 .Sx "COMMAND ESCAPES"
230 for compose mode commands).
234 (\*(OB: \*(UA will always use line-buffered output, to gain
235 line-buffered input even in batch mode enable batch mode via
240 Send a blind carbon copy to
243 May be used multiple times.
245 .Sx "On sending mail, and non-interactive mode" .
249 Send carbon copies to the given receiver.
250 May be used multiple times.
255 the internal variable
257 which enables debug messages and disables message delivery,
258 among others; effectively turns almost any operation into a dry-run.
264 and thus discard messages with an empty message part body.
265 This command line flag is \*(OB.
269 Just check if mail is present (in the specified or system
271 if yes, return an exit status of zero, a non-zero value otherwise.
272 To restrict the set of mails to consider in this evaluation a message
273 specification can be added with the option
278 Save the message to send in a file named after the local part of the
279 first recipient's address (instead of in
284 Read in the contents of the user's
286 (or the specified file) for processing;
287 when \*(UA is quit, it writes undeleted messages back to this file
293 argument will undergo some special
295 .Sx "filename transformations" ,
296 which are documented in the introductional section of
298 as well as for the command
302 is not a argument to the flag
304 but is instead taken from the command line after option processing has
308 that starts with a hyphen, prefix it with a (relative) path, as in
309 .Ql ./-hyphenbox.mbox .
313 Display a summary of the
315 of all messages in the specified mailbox or system
318 A configurable summary view is available via the
324 Show a short usage summary.
325 Because of widespread use a
327 argument will have the same effect.
333 to ignore tty interrupt signals.
336 .It Fl L Ar spec-list
337 Display a summary of all
339 of only those messages in the specified mailbox or the system
345 .Sx "Specifying messages"
352 option has been given in addition no header summary is produced,
353 but \*(UA will instead indicate via its exit status whether
359 note that any verbose output is suppressed in this mode and must instead
360 be enabled explicitly (e.g., by using the option
365 Special send mode that will flag standard input with the MIME
369 and use it as the main message body.
370 \*(ID Using this option will bypass processing of
371 .Va message-inject-head ,
374 .Va message-inject-tail .
380 Special send mode that will MIME classify the specified
382 and use it as the main message body.
383 \*(ID Using this option will bypass processing of
384 .Va message-inject-head ,
387 .Va message-inject-tail .
395 and thus inhibit initial display of message headers when reading mail or
396 editing a mail folder.
400 Standard flag that inhibits reading the system wide
405 allows more control over the startup sequence; also see
406 .Sx "Resource files" .
410 Special send mode that will initialize the message body with the
411 contents of the specified
413 which may be standard input
415 only in non-interactive context.
421 Any folder opened will be in read-only mode.
425 .It Fl r Ar from-addr
426 The source address that appears in the
429 header of a message (or in the
432 header if the former contains multiple addresses) is not used for
433 relaying and delegating a message over the wire via SMTP, but instead an
434 envelope will enwrap the message content and provide the necessary
435 information (i.e., the RFC 5321 reverse-path, also used to report, e.g.,
436 delivery errors) to transmit the message to its destination(s).
437 Whereas the said headers and internal variables will be used by \*(UA to
438 create the envelope if the builtin SMTP
440 (Mail-Transfer-Agent) is used, a file-based MTA will instead use the
441 identity of the message-originating user.
443 This command line option can be used to specify the reverse-path, to be
444 passed to a file-based
446 when a message is sent, via
447 .Ql -f Ar from-addr .
450 include a user name, then the address components will be separated and
451 the name part will be passed to a file-based
457 is also assigned to the internal variable
459 Many default installations and sites disallow explicit overriding of the
460 user identity which could be adjusted by this option, unless either
462 has been configured accordingly, or the user is member of a group with
463 special privileges, respectively.
465 If an empty string is passed as
467 then the content of the variable
469 (or, if that contains multiple addresses,
471 will be evaluated and used for this purpose whenever the file-based
474 Note that \*(UA by default, without
476 that is, neither passes
480 flags to a file-based MTA by itself, unless this automatic deduction is
483 ing the internal variable
484 .Va r-option-implicit .
488 .It Fl S Ar var Ns Op = Ns value
492 iable and, in case of a non-boolean variable which has a value, assign
496 .Sx "INTERNAL VARIABLES"
500 may be overwritten from within resource files,
501 the command line setting will be reestablished after all resource files
506 Specify the subject of the message to be sent.
507 Newline (NL) and carriage-return (CR) bytes are invalid and will be
508 normalized to space (SP) characters.
512 The message given (on standard input) is expected to contain, separated
513 from the message body by an empty line, a message header with
518 fields giving its recipients, which will be added to any recipients
519 specified on the command line.
520 If a message subject is specified via
522 then it will be used in favour of one given on the command line.
538 .Ql Mail-Followup-To: ,
539 by default created automatically dependent on message context, will
540 be used if specified (a special address massage will however still occur
542 Any other (also custom) header field is passed through entirely
543 unchanged, and in conjunction with the option
545 it is possible to embed
546 .Sx "COMMAND ESCAPES" .
554 .Sx "primary system mailbox"
557 appropriate privileges presumed; effectively identical to
567 will also show the list of
569 .Ql $ \*(uA -Xversion -Xx .
574 ting the internal variable
576 enables display of some informational context messages.
577 Using it twice increases the level of verbosity.
581 Add the given (or multiple for a multiline argument)
583 to the list of commands to be executed (as a unit, just as via
585 as a last step of program startup, before normal operation starts.
589 .Va batch-exit-on-error ;
590 the only possibility to execute commands in non-interactive mode when
591 reading startup files is actively prohibited.
596 .Sx "COMMAND ESCAPES"
597 even if not in interactive mode.
598 This can be used to, e.g., automatically format the composed message
599 text before sending the message:
600 .Bd -literal -offset indent
601 $ ( echo 'line one. Word. Word2.'; \e
602 echo '~| /usr/bin/fmt -tuw66' ) |\e
603 LC_ALL=C \*(uA -:/ -Sttycharset=UTF-8 -d~ bob@exam.ple
609 In batch mode the full set of commands is available, just like in
610 interactive mode, standard input is made line buffered, and diverse
611 .Sx "INTERNAL VARIABLES"
612 are adjusted for batch necessities, e.g., it
628 .Sx "COMMAND ESCAPES"
629 is enabled in compose mode.
630 The following prepares an email message in a batched dry run:
631 .Bd -literal -offset indent
632 $ LC_ALL=C printf 'm bob\en~s ubject\enText\en~.\enx\en' | \e
633 LC_ALL=C \*(uA -:/ -d# -X'alias bob bob@exam.ple'
638 This flag forces termination of option processing in order to prevent
641 It also forcefully puts \*(UA into send mode, see
642 .Sx "On sending mail, and non-interactive mode" .
646 In the above list of supported command line options,
650 are implemented by means of
652 ting the respective internal variable, as via
655 .Op Ar mta-option ...
657 arguments that are given at the end of the command line after a
659 separator will be passed through to a file-based
661 (Mail-Transfer-Agent) and persist for an entire (interactive) session
662 \(en if the setting of
664 allows their recognition; no such constraints apply to the variable
668 .\" .Ss "A starter" {{{
671 \*(UA is a direct descendant of
673 Mail, a successor of the Research
676 .Dq was there from the start
681 Mail reference manual begins with the following words:
683 .Bd -ragged -offset indent
684 Mail provides a simple and friendly environment for sending and
686 It divides incoming mail into its constituent messages and allows the
687 user to deal with them in any order.
688 In addition, it provides a set of
690 -like commands for manipulating messages and sending mail.
691 Mail offers the user simple editing capabilities to ease the composition
692 of outgoing messages, as well as providing the ability to define and
693 send to names which address groups of users.
697 \*(UA is thus the user side of the
699 mail system, whereas the system side (Mail-Transfer-Agent, MTA) was
700 traditionally taken by
702 and most MTAs provide a binary of this name for compatibility purposes.
707 of \*(UA then the system side is not a mandatory precondition for mail
711 Because \*(UA strives for compliance with POSIX
713 it is likely that some configuration settings have to be adjusted before
714 using it is a smooth experience.
717 resource file bends those standard imposed settings of the
718 .Sx "INTERNAL VARIABLES"
719 a bit towards more user friendliness and safety, however, e.g., it
724 in order to suppress the automatic moving of messages to
726 that would otherwise occur (see
727 .Sx "Message states" ) ,
730 to not remove empty system (MBOX) mailbox files in order not to mangle
731 file permissions when files eventually get recreated; be aware that
732 \*(UA will (try to) remove all empty (MBOX) mailbox files unless this
733 variable is set in case
735 .Pf ( Ev POSIXLY_CORRECT )
736 mode has been enabled.
737 The file mode creation mask is explicitly managed via
743 in order to synchronize \*(UA with the exit status report of the used
748 to enter interactive startup even if the initial mailbox is empty,
750 to allow editing of headers as well as
752 to not strip down addresses in compose mode, and
754 to include the message that is being responded to when
759 contains some more complete configuration examples.
762 .\" .Ss "On sending mail, and non-interactive mode" {{{
763 .Ss "On sending mail, and non-interactive mode"
765 To send a message to one or more people, using a local or a builtin
767 (Mail-Transfer-Agent) transport to actually deliver the generated mail
768 message, \*(UA can be invoked with arguments which are the names of
769 people to whom the mail will be sent, and the command line options
773 can be used to add (blind) carbon copy receivers:
775 .Bd -literal -offset indent
776 $ \*(uA -s ubject -a ttach.txt bill@exam.ple
777 # But... try it in an isolated dry-run mode first
778 $ LC_ALL=C \*(uA -:/ -d -vv -Ssendwait \e
779 -b bcc@exam.ple -c cc@exam.ple -. \e
780 '(Lovely) Bob <bob@exam.ple>' eric@exam.ple
782 $ LC_ALL=C \*(uA -:/ -d -vv -Sv15-compat -Ssendwait \e
783 -S 'mta=smtps://mylogin@exam.ple:465' -Ssmtp-auth=login \e
784 -S 'from=scriptreply@exam.ple' \e
790 If standard input is a terminal rather than the message to be sent,
791 the user is expected to type in the message contents.
792 In this compose mode \*(UA treats lines beginning with the character
794 special \(en these are so-called
795 .Sx "COMMAND ESCAPES"
796 which can be used to read in files, process shell commands, add and edit
797 attachments and more; e.g., the command escape
799 will start the text editor to revise the message in its current state,
801 allows editing of the most important message headers and
803 gives an overview of available command escapes.
807 at the beginning of an empty line leaves compose mode and causes the
808 message to be sent, whereas typing
811 twice will abort the current letter (saving its contents in the file
817 Messages are sent asynchronously, without supervision, unless the variable
819 is set, therefore send errors are not recognizable until then.
825 .Sx "INTERNAL VARIABLES"
826 can be used to alter default behavior; e.g.,
831 will automatically startup a text editor when compose mode is entered,
833 allows editing of headers additionally to plain body content,
835 will cause the user to be prompted actively for carbon-copy recipients
838 will allow leaving compose mode by writing a line consisting solely of
844 hook macros may be set to automatically adjust some settings dependent
845 on receiver, sender or subject contexts, and
846 .Va on-compose-done-shell
849 are increasingly powerful mechanisms to perform automated message
850 adjustments in between.
853 Especially for using public mail provider accounts with the SMTP
855 it is often necessary to set
857 and saving a copy of sent messages in a
859 may be desirable \(en as for most mailbox
861 targets the value will undergo
863 .Sx "filename transformations" ,
864 also see the introduction of
869 for the purpose of arranging a complete environment of settings that can
870 be switched to with a single command or command line option may be
873 contains example configurations for sending messages via some of the
874 well-known public mail providers and also gives a compact overview on
875 how to setup a secure SSL/TLS environment).
880 sandbox dry-run tests first will prove correctness.
884 .Sx "On URL syntax and credential lookup"
885 will spread light on the different ways of how to specify user email
886 account credentials, the
888 variable chains, and accessing protocol-specific resources,
891 goes into the details of character encoding and how to use them for
892 representing messages and MIME part contents by specifying them in
894 and reading the section
895 .Sx "The mime.types files"
896 should help to understand how the MIME-type of outgoing attachments are
897 classified, and what can be done for fine-tuning.
898 Over the wire an intermediate, configurable
899 .Pf content-transfer-\: Va encoding
900 may be applied to the raw message part data.
903 Message recipients (as specified on the command line or defined in
908 may not only be email addressees but can also be names of mailboxes and
909 even complete shell command pipe specifications.
912 is not set then only network addresses (see
914 for a description of mail addresses) and plain user names (including MTA
915 aliases) may be used, other types will be filtered out, giving a warning
918 .\" When changing any of the following adjust any RECIPIENTADDRSPEC;
919 .\" grep the latter for the complete picture
923 is set then extended recipient addresses will optionally be accepted:
924 Any name which starts with a vertical bar
926 character specifies a command pipe \(en the command string following the
928 is executed and the message is sent to its standard input;
929 Likewise, any name that starts with the character solidus
931 or the character sequence dot solidus
933 is treated as a file, regardless of the remaining content;
934 likewise a name that solely consists of a hyphen
936 Any other name which contains an at sign
938 character is treated as a network address;
939 Any other name which starts with a plus sign
941 character specifies a mailbox name;
942 Any other name which contains a solidus
944 character but no exclamation mark
948 character before also specifies a mailbox name;
949 What remains is treated as a network address.
951 .Bd -literal -offset indent
952 $ echo bla | \*(uA -Sexpandaddr -s test ./mbox.mbox
953 $ echo bla | \*(uA -Sexpandaddr -s test '|cat >> ./mbox.mbox'
954 $ echo safe | LC_ALL=C \e
955 \*(uA -:/ -Sv15-compat -Ssendwait -Snosave \e
956 -Sexpandaddr=fail,-all,+addr -s test \e
961 It is possible to create personal distribution lists via the
963 command, so that, for instance, the user can send mail to
965 and have it go to a group of people.
966 These aliases have nothing in common with the system wide aliases that
967 may be used by the MTA, which are subject to the
971 and are often tracked in a file
977 Personal aliases will be expanded by \*(UA before the message is sent,
978 and are thus a convenient alternative to specifying each addressee by
982 .Dl alias cohorts bill jkf mark kridle@ucbcory ~/mail/cohorts.mbox
985 To avoid environmental noise scripts should
987 \*(UA from any configuration files and create a script-local
988 environment, ideally with the command line options
990 to disable any configuration file in conjunction with repetitions of
992 to specify variables:
994 .Bd -literal -offset indent
995 $ env LC_ALL=C \*(uA -:/ \e
996 -Sv15-compat -Ssendwait -Snosave -Sttycharset=utf-8 \e
997 -Sexpandaddr=fail,-all,+addr \e
998 -S 'mta=smtps://mylogin@exam.ple:465' -Ssmtp-auth=login \e
999 -S 'from=scriptreply@exam.ple' \e
1000 -s 'subject' -a attachment_file \e
1001 -. "Recipient 1 <rec1@exam.ple>" rec2@exam.ple \e
1006 As shown, scripts can
1008 a locale environment, the above specifies the all-compatible 7-bit clean
1011 but will nonetheless take and send UTF-8 in the message text by using
1013 In interactive mode, which is introduced in the next section, messages
1014 can be sent by calling the
1016 command with a list of recipient addresses \(em the semantics are
1017 completely identical to non-interactive message sending:
1019 .Bd -literal -offset indent
1020 $ \*(uA -d -Squiet -Semptystart
1021 "/var/spool/mail/user": 0 messages
1022 ? mail "Recipient 1 <rec1@exam.ple>", rec2@exam.ple
1023 ? # Will do the right thing (tm)
1024 ? m rec1@exam.ple rec2@exam.ple
1028 .\" .Ss "On reading mail, and interactive mode" {{{
1029 .Ss "On reading mail, and interactive mode"
1031 When invoked without addressees \*(UA enters interactive mode in which
1033 When used like that the user's system
1037 for an in-depth description of the different mailbox types that exist)
1038 is read in and a one line header of each message therein is displayed.
1039 The visual style of this summary of
1041 can be adjusted through the variable
1043 and the possible sorting criterion via
1049 can be performed with the command
1051 If the initially opened mailbox is empty \*(UA will instead exit
1052 immediately (after displaying a message) unless the variable
1061 will give a listing of all available commands and
1063 will give a summary of some common ones.
1064 If the \*(OPal documentation strings are available one can type
1067 and see the actual expansion of
1069 and what its purpose is, i.e., commands can be abbreviated
1070 (note that POSIX defines some abbreviations, so that the alphabetical
1071 order of commands does not necessarily relate to the abbreviations; it is
1072 possible to define overwrites with the
1075 These commands can also produce a more
1080 Messages are given numbers (starting at 1) which uniquely identify
1081 messages; the current message \(en the
1083 \(en will either be the first new message, or the first unread message,
1084 or the first message of the mailbox; the internal variable
1086 will instead cause usage of the last message for this purpose.
1091 ful of header summaries containing the
1095 will display only the summaries of the given messages, defaulting to the
1099 Message content can be displayed on the users' terminal with the
1103 If instead the command
1105 is used, only the first
1107 of a message will be shown.
1108 By default the current message
1110 is displayed, but like with many other commands it is possible to give
1111 a fancy message specification (see
1112 .Sx "Specifying messages" ) ,
1115 will display all unread messages,
1120 will type the messages 1 and 5,
1122 will type the messages 1 through 5, and
1126 will display the last and the next message, respectively.
1129 (a more substantial alias of the standard command
1131 will display a header summary of the given message specification list
1132 instead of their content, e.g., the following will search for subjects:
1135 .Dl from "'@Some subject to search for'"
1138 In the default setup all header fields of a message will be
1140 d, but fields can be white- or blacklisted for a variety of
1141 applications by using the command
1143 e.g., to restrict display to a very restricted set:
1144 .Ql Ic \:headerpick Cd \:type retain add Ar \:from to cc subject .
1145 In order to display all header fields of a message regardless of
1146 currently active ignore or retain lists, use the commands
1152 controls whether and when \*(UA will use the configured
1154 for display instead of directly writing to the user terminal
1156 (generally speaking).
1157 Note that historically the global
1159 not only adjusts the list of displayed headers, but also sets
1163 Dependent upon the configuration a line editor (see the section
1164 .Sx "On terminal control and line editor" )
1165 aims at making user experience with the many
1168 When reading the system
1174 specified a mailbox explicitly prefixed with the special
1176 modifier (propagating the mailbox to a
1178 .Sx "primary system mailbox" ) ,
1179 then messages which have been read will be moved to a
1181 .Sx "secondary mailbox" ,
1184 file, automatically when the mailbox is left, either by changing the
1185 active mailbox or by quitting \*(UA (also see
1186 .Sx "Message states" )
1187 \(en this automatic moving from a system or primary to the secondary
1188 mailbox is not performed when the variable
1193 After examining a message the user can also
1197 to the sender and all recipients or
1199 exclusively to the sender(s).
1200 Messages can also be
1202 ed (shorter alias is
1204 Note that when replying to or forwarding a message recipient addresses
1205 will be stripped from comments and names unless the internal variable
1208 Deletion causes \*(UA to forget about the message;
1209 This is not irreversible, though, one can
1211 the message by giving its number,
1212 or the \*(UA session can be ended by giving the
1217 To end a mail processing session one may either issue
1219 to cause a full program exit, which possibly includes
1220 automatic moving of read messages to
1222 as well as updating the \*(OPal line editor
1226 instead in order to prevent any of these actions.
1229 .\" .Ss "HTML mail and MIME attachments" {{{
1230 .Ss "HTML mail and MIME attachments"
1232 Messages which are HTML-only get more and more common and of course many
1233 messages come bundled with a bouquet of MIME attachments.
1234 Whereas \*(UA \*(OPally supports a simple HTML-to-text converter to deal
1235 with HTML messages (see
1236 .Sx "The mime.types files" ) ,
1237 it normally cannot deal with any of these itself, but instead programs
1238 need to become registered to deal with specific MIME types or file
1240 These programs may either prepare plain text versions of their input
1241 in order to enable \*(UA to display the content on the terminal,
1242 or display the content themselves, for example in a graphical window.
1245 To install an external handler program for a specific MIME type set an
1247 .Va pipe-TYPE/SUBTYPE
1248 variable; to instead define a handler for a specific file extension set
1251 variable \(en these handlers take precedence.
1252 \*(OPally \*(UA supports mail user agent configuration as defined in
1253 RFC 1524; this mechanism, documented in the section
1254 .Sx "The Mailcap files" ,
1255 will be queried for display or quote handlers if none of the former two
1256 .\" TODO v15-compat "will be" -> "is"
1257 did; it will be the sole source for handlers of other purpose.
1258 A last source for handlers may be the MIME type definition itself, if
1259 the \*(UA specific type-marker extension was used when defining the type
1262 (Many of the builtin MIME types do so by default.)
1266 .Va mime-counter-evidence
1267 can be set to improve dealing with faulty MIME part declarations as are
1268 often seen in real-life messages.
1269 E.g., to display a HTML message inline (that is, converted to a more
1270 fancy plain text representation than the builtin converter is capable to
1271 produce) with either of the text-mode browsers
1275 teach \*(UA about MathML documents and make it display them as plain
1276 text, and to open PDF attachments in an external PDF viewer,
1277 asynchronously and with some other magic attached:
1279 .Bd -literal -offset indent
1280 if $features !@ +filter-html-tagsoup
1281 #set pipe-text/html='elinks -force-html -dump 1'
1282 set pipe-text/html='lynx -stdin -dump -force_html'
1283 # Display HTML as plain text instead
1284 #set pipe-text/html=@
1286 mimetype '@ application/mathml+xml mathml'
1287 wysh set pipe-application/pdf='@&=@ \e
1288 trap "rm -f \e"${NAIL_FILENAME_TEMPORARY}\e"" EXIT;\e
1289 trap "trap \e"\e" INT QUIT TERM; exit 1" INT QUIT TERM;\e
1290 mupdf "${NAIL_FILENAME_TEMPORARY}"'
1294 Note: special care must be taken when using such commands as mail
1295 viruses may be distributed by this method: if messages of type
1296 .Ql application/x-sh
1297 or files with the extension
1299 were blindly filtered through the shell, for example, a message sender
1300 could easily execute arbitrary code on the system \*(UA is running on.
1301 For more on MIME, also in respect to sending of messages, see the
1303 .Sx "The mime.types files" ,
1304 .Sx "The Mailcap files"
1309 .\" .Ss "Mailing lists" {{{
1312 \*(UA offers some support to ease handling of mailing lists.
1315 promotes all given arguments to known mailing lists, and
1317 sets their subscription attribute, creating them first as necessary.
1322 automatically, but only resets the subscription attribute.)
1323 Using the commands without arguments will show (a subset of) all
1324 currently defined mailing lists.
1329 can be used to mark out messages with configured list addresses
1330 in the header display.
1333 \*(OPally mailing lists may also be specified as (extended) regular
1334 expressions, which allows matching of many addresses with a single
1336 However, all fully qualified list addresses are matched via a fast
1337 dictionary, whereas expressions are placed in (a) list(s) which is
1338 (are) matched sequentially.
1340 .Bd -literal -offset indent
1341 set followup-to followup-to-honour=ask-yes reply-to-honour=ask-yes
1342 wysh mlist a1@b1.c1 a2@b2.c2 '.*@lists\e.c3$'
1343 mlsubscribe a4@b4.c4 exact@lists.c3
1348 .Va followup-to-honour
1350 .Ql Mail-\:Followup-\:To:
1351 header is honoured when the message is being replied to (via
1357 controls whether this header is created when sending mails; it will be
1358 created automatically for a couple of reasons, too, like when the
1360 .Dq mailing list specific
1365 is used to respond to a message with its
1366 .Ql Mail-Followup-To:
1370 A difference in between the handling of known and subscribed lists is
1371 that the address of the sender is usually not part of a generated
1372 .Ql Mail-Followup-To:
1373 when addressing the latter, whereas it is for the former kind of lists.
1374 Usually because there are exceptions: say, if multiple lists are
1375 addressed and not all of them are subscribed lists.
1377 For convenience \*(UA will, temporarily, automatically add a list
1378 address that is presented in the
1380 header of a message that is being responded to to the list of known
1382 Shall that header have existed \*(UA will instead, dependent on the
1384 .Va reply-to-honour ,
1387 for this purpose in order to accept a list administrators' wish that
1388 is supposed to have been manifested like that (but only if it provides
1389 a single address which resides on the same domain as what is stated in
1393 .\" .Ss "Resource files" {{{
1394 .Ss "Resource files"
1396 Upon startup \*(UA reads in several resource files:
1398 .Bl -tag -width ".It Pa BaNg"
1401 System wide initialization file.
1402 Reading of this file can be suppressed, either by using the
1406 command line options, or by setting the
1409 .Ev NAIL_NO_SYSTEM_RC .
1413 File giving initial commands.
1414 A different file can be chosen by setting the
1418 Reading of this file can be suppressed with the
1420 command line option.
1422 .It Va NAIL_EXTRA_RC
1423 Can be used to define an optional startup file to be read after all
1424 other resource files.
1425 It can be used to specify settings that are not understood by other
1427 implementations, for example.
1428 This variable is only honoured when defined in a resource file, e.g.,
1430 .Sx "INTERNAL VARIABLES" .
1434 The content of these files is interpreted as follows:
1437 .Bl -bullet -compact
1439 A lines' leading whitespace is removed.
1441 Empty lines are ignored.
1443 Any other line is interpreted as a command.
1444 It may be spread over multiple input lines if the newline character is
1446 by placing a reverse solidus character
1448 as the last character of the line; whereas any leading whitespace of
1449 follow lines is ignored, trailing whitespace before a escaped newline
1450 remains in the input.
1452 If the line (content) starts with the number sign
1454 then it is a comment-command \(en a real command! \(en and also ignored.
1455 This command is the only form of comment that is understood.
1459 Unless \*(UA is about to enter interactive mode syntax errors that occur
1460 while loading these files are treated as errors and cause program exit.
1461 More files with syntactically equal content can be
1463 The following, saved in a file, would be an examplary content:
1465 .Bd -literal -offset indent
1466 # This line is a comment command. And y\e
1467 es, it is really continued here.
1474 .\" .Ss "Character sets" {{{
1475 .Ss "Character sets"
1477 \*(OP \*(UA detects the character set of the terminal by using
1478 mechanisms that are controlled by the
1483 should give an overview); the \*(UA internal variable
1485 will be set to the detected terminal character set accordingly
1486 and will thus show up in the output of the commands
1492 However, a user supplied
1494 value is not overwritten by this detection mechanism: this
1496 must be used if the detection does not work properly,
1497 and it may be used to adjust the name of the locale character set.
1498 E.g., on BSD systems one may use a locale with the character set
1499 ISO8859-1, which is not a valid name for this character set; to be on
1500 the safe side, one may set
1502 to the correct name, which is ISO-8859-1.
1505 Note that changing the value does not mean much beside that,
1506 since several aspects of the real character set are implied by the
1507 locale environment of the system,
1508 and that stays unaffected by the content of an overwritten
1511 (This is mostly an issue when interactively using \*(UA, though.
1512 It is actually possible to send mail in a completely
1514 locale environment, an option that \*(UA's test-suite uses excessively.)
1517 If no character set conversion capabilities have been compiled into
1520 does not include the term
1524 will be the only supported character set,
1525 it is simply assumed that it can be used to exchange 8-bit messages
1526 (over the wire an intermediate
1527 .Pf content-transfer-\: Va encoding
1529 and the rest of this section does not apply;
1530 it may however still be necessary to explicitly set it if automatic
1531 detection fails, since in that case it defaults to the mentioned
1532 .\" (Keep in SYNC: ./nail.1:"Character sets", ./nail.h:CHARSET_*!)
1536 When reading messages, their text is converted into
1538 as necessary in order to display them on the users terminal.
1539 Unprintable characters and invalid byte sequences are detected
1540 and replaced by proper substitution characters (unless the variable
1542 was set once \*(UA was started).
1544 .Va charset-unknown-8bit
1545 to deal with another hairy aspect of message interpretation.
1548 When sending messages all their parts and attachments are classified.
1549 Whereas no character set conversion is performed on those parts which
1550 appear to be binary data,
1551 the character set being used must be declared within the MIME header of
1552 an outgoing text part if it contains characters that do not conform to
1553 the set of characters that are allowed by the email standards.
1554 Permissible values for character sets can be declared using the
1558 which defines a catch-all last-resort fallback character set that is
1559 implicitly appended to the list of character-sets in
1563 When replying to a message and the variable
1564 .Va reply-in-same-charset
1565 is set then the character set of the message being replied to is tried
1567 And it is also possible to make \*(UA work even more closely related to
1568 the current locale setting automatically by using the variable
1569 .Va sendcharsets-else-ttycharset ,
1570 please see there for more information.
1573 All the specified character sets are tried in order unless the
1574 conversion of the part or attachment succeeds.
1575 If none of the tried (8-bit) character sets is capable to represent the
1576 content of the part or attachment,
1577 then the message will not be sent and its text will optionally be
1581 In general, if the message
1582 .Dq Cannot convert from a to b
1583 appears, either some characters are not appropriate for the currently
1584 selected (terminal) character set,
1585 or the needed conversion is not supported by the system.
1586 In the first case, it is necessary to set an appropriate
1588 locale and/or the variable
1592 The best results are usually achieved when \*(UA is run in a UTF-8
1593 locale on a UTF-8 capable terminal, in which case the full Unicode
1594 spectrum of characters is available.
1595 In this setup characters from various countries can be displayed,
1596 while it is still possible to use more simple character sets for sending
1597 to retain maximum compatibility with older mail clients.
1600 On the other hand the POSIX standard defines a locale-independent 7-bit
1601 .Dq portable character set
1602 that should be used when overall portability is an issue, the even more
1603 restricted subset named
1604 .Dq portable filename character set
1605 consisting of A-Z, a-z, 0-9, period
1614 .\" .Ss "Message states" {{{
1615 .Ss "Message states"
1617 \*(UA differentiates in between several different message states;
1618 the current state will be reflected in header summary displays if
1620 is configured to do so (via the internal variable
1622 and messages can also be selected and be acted upon depending on their
1624 .Sx "Specifying messages" ) .
1625 When operating on the system
1629 .Sx "primary system mailbox" ,
1630 special actions, like the automatic moving of messages to the
1632 .Sx "secondary mailbox"
1634 may be applied when the mailbox is left (also implicitly via
1635 a successful exit of \*(UA, but not if the special command
1637 is used) \(en however, because this may be irritating to users which
1640 mail-user-agents, the default global
1646 variables in order to suppress this behaviour.
1648 .Bl -tag -width ".It Ql BaNg"
1650 Message has neither been viewed nor moved to any other state.
1651 Such messages are retained even in the
1653 .Sx "primary system mailbox" .
1656 Message has neither been viewed nor moved to any other state, but the
1657 message was present already when the mailbox has been opened last:
1658 Such messages are retained even in the
1660 .Sx "primary system mailbox" .
1663 The message has been processed by one of the following commands:
1683 commands may also cause the next message to be marked as read, depending
1689 command is used, messages that are in a
1691 .Sx "primary system mailbox"
1694 state when the mailbox is left will be saved in
1696 unless the internal variable
1701 The message has been processed by one of the following commands:
1707 can be used to access such messages.
1710 The message has been processed by a
1712 command and it will be retained in its current location.
1715 The message has been processed by one of the following commands:
1721 command is used, messages that are in a
1723 .Sx "primary system mailbox"
1726 state when the mailbox is left will be deleted; they will be saved in
1728 when the internal variable
1734 .\" .Ss "Specifying messages" {{{
1735 .Ss "Specifying messages"
1742 can be given a list of message numbers as arguments to apply to a number
1743 of messages at once.
1746 deletes messages 1 and 2,
1749 will delete the messages 1 through 5.
1750 In sorted or threaded mode (see the
1754 will delete the messages that are located between (and including)
1755 messages 1 through 5 in the sorted/threaded order, as shown in the
1758 The following special message names exist:
1761 .Bl -tag -width ".It Ar BaNg"
1763 The current message, the so-called
1767 The message that was previously the current message.
1770 The parent message of the current message,
1771 that is the message with the Message-ID given in the
1773 field or the last entry of the
1775 field of the current message.
1778 The next previous undeleted message,
1779 or the next previous deleted message for the
1782 In sorted/threaded mode,
1783 the next previous such message in the sorted/threaded order.
1786 The next undeleted message,
1787 or the next deleted message for the
1790 In sorted/threaded mode,
1791 the next such message in the sorted/threaded order.
1794 The first undeleted message,
1795 or the first deleted message for the
1798 In sorted/threaded mode,
1799 the first such message in the sorted/threaded order.
1803 In sorted/threaded mode,
1804 the last message in the sorted/threaded order.
1808 selects the message addressed with
1812 is any other message specification,
1813 and all messages from the thread that begins at it.
1814 Otherwise it is identical to
1819 the thread beginning with the current message is selected.
1824 All messages that were included in the message list for the previous
1828 An inclusive range of message numbers.
1829 Selectors that may also be used as endpoints include any of
1834 .Dq any substring matches
1837 header, which will match addresses (too) even if
1839 is set (and POSIX says
1840 .Dq any address as shown in a header summary shall be matchable in this form ) ;
1843 variable is set, only the local part of the address is evaluated
1844 for the comparison, not ignoring case, and the setting of
1846 is completely ignored.
1847 For finer control and match boundaries use the
1851 .It Ar / Ns Ar string
1852 All messages that contain
1854 in the subject field (case ignored).
1861 the string from the previous specification of that type is used again.
1863 .It Xo Op Ar @ Ns Ar name-list Ns
1866 All messages that contain the given case-insensitive search
1868 ession; if the \*(OPal regular expression (see
1870 support is available
1872 will be interpreted as (an extended) one if any of the
1874 (extended) regular expression characters is seen.
1876 .Ar @ Ns Ar name-list
1877 part is missing, the search is restricted to the subject field body,
1880 specifies a comma-separated list of header fields to search, as in
1882 .Dl '@to,from,cc@Someone i ought to know'
1884 In order to search for a string that includes a
1886 (commercial at) character the
1888 is effectively non-optional, but may be given as the empty string.
1889 Some special header fields may be abbreviated:
1903 respectively and case-insensitively.
1908 can be used to search in (all of) the header(s) of the message, and the
1917 can be used to perform full text searches \(en whereas the former
1918 searches only the body, the latter also searches the message header.
1920 This message specification performs full text comparison, but even with
1921 regular expression support it is almost impossible to write a search
1922 expression that savely matches only a specific address domain.
1923 To request that the content of the header is treated as a list of
1924 addresses, and to strip those down to the plain email address which the
1925 search expression is to be matched against, prefix the header name
1926 (abbreviation) with a tilde
1929 .Dl @~f@@a\e.safe\e.domain\e.match$
1932 All messages of state
1936 is one or multiple of the following colon modifiers:
1938 .Bl -tag -compact -width ".It Ar :M"
1943 Old messages (any not in state
1969 Messages marked as draft.
1971 \*(OP Messages classified as spam.
1973 \*(OP Messages with unsure spam classification.
1979 \*(OP IMAP-style SEARCH expressions may also be used.
1980 This addressing mode is available with all types of folders;
1981 \*(UA will perform the search locally as necessary.
1982 Strings must be enclosed by double quotes
1984 in their entirety if they contain white space or parentheses;
1985 within the quotes, only reverse solidus
1987 is recognized as an escape character.
1988 All string searches are case-insensitive.
1989 When the description indicates that the
1991 representation of an address field is used,
1992 this means that the search string is checked against both a list
1995 .Bd -literal -offset indent
1996 (\*qname\*q \*qsource\*q \*qlocal-part\*q \*qdomain-part\*q)
2001 and the addresses without real names from the respective header field.
2002 These search expressions can be nested using parentheses, see below for
2006 .Bl -tag -compact -width ".It Ar _n_u"
2007 .It Ar ( criterion )
2008 All messages that satisfy the given
2010 .It Ar ( criterion1 criterion2 ... criterionN )
2011 All messages that satisfy all of the given criteria.
2013 .It Ar ( or criterion1 criterion2 )
2014 All messages that satisfy either
2019 To connect more than two criteria using
2021 specifications have to be nested using additional parentheses,
2023 .Ql (or a (or b c)) ,
2027 .Ql ((a or b) and c) .
2030 operation of independent criteria on the lowest nesting level,
2031 it is possible to achieve similar effects by using three separate
2035 .It Ar ( not criterion )
2036 All messages that do not satisfy
2038 .It Ar ( bcc \*q Ns Ar string Ns Ar \*q )
2039 All messages that contain
2041 in the envelope representation of the
2044 .It Ar ( cc \*q Ns Ar string Ns Ar \*q )
2045 All messages that contain
2047 in the envelope representation of the
2050 .It Ar ( from \*q Ns Ar string Ns Ar \*q )
2051 All messages that contain
2053 in the envelope representation of the
2056 .It Ar ( subject \*q Ns Ar string Ns Ar \*q )
2057 All messages that contain
2062 .It Ar ( to \*q Ns Ar string Ns Ar \*q )
2063 All messages that contain
2065 in the envelope representation of the
2068 .It Ar ( header name \*q Ns Ar string Ns Ar \*q )
2069 All messages that contain
2074 .It Ar ( body \*q Ns Ar string Ns Ar \*q )
2075 All messages that contain
2078 .It Ar ( text \*q Ns Ar string Ns Ar \*q )
2079 All messages that contain
2081 in their header or body.
2082 .It Ar ( larger size )
2083 All messages that are larger than
2086 .It Ar ( smaller size )
2087 All messages that are smaller than
2091 .It Ar ( before date )
2092 All messages that were received before
2094 which must be in the form
2098 denotes the day of the month as one or two digits,
2100 is the name of the month \(en one of
2101 .Ql Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ,
2104 is the year as four digits, e.g.,
2108 All messages that were received on the specified date.
2109 .It Ar ( since date )
2110 All messages that were received since the specified date.
2111 .It Ar ( sentbefore date )
2112 All messages that were sent on the specified date.
2113 .It Ar ( senton date )
2114 All messages that were sent on the specified date.
2115 .It Ar ( sentsince date )
2116 All messages that were sent since the specified date.
2118 The same criterion as for the previous search.
2119 This specification cannot be used as part of another criterion.
2120 If the previous command line contained more than one independent
2121 criterion then the last of those criteria is used.
2125 .\" .Ss "On URL syntax and credential lookup" {{{
2126 .Ss "On URL syntax and credential lookup"
2128 \*(IN For accessing protocol-specific resources usage of Uniform
2129 Resource Locators (URL, RFC 1738) has become omnipresent.
2130 \*(UA expects and understands URLs in the following form;
2133 denote optional parts, optional either because there also exist other
2134 ways to define the information in question or because support of the
2135 part is protocol-specific (e.g.,
2137 is used by the IMAP protocol but not by POP3);
2142 are specified they must be given in URL percent encoded form (RFC 3986;
2148 .Dl PROTOCOL://[USER[:PASSWORD]@]server[:port][/path]
2151 Note that these \*(UA URLs most often do not conform to any real
2152 standard, but instead represent a normalized variant of RFC 1738 \(en
2153 they are not used in data exchange but only meant as a compact,
2154 easy-to-use way of defining and representing information in
2155 a well-known notation.
2158 Many internal variables of \*(UA exist in multiple versions, called
2159 variable chains for the rest of this document: the plain
2164 .Ql variable-USER@HOST .
2171 had been specified in the respective URL, otherwise it refers to the plain
2177 that had been found when doing the user chain lookup as is described
2180 will never be in URL percent encoded form, whether it came from an URL
2181 or not; i.e., variable chain name extensions of
2182 .Sx "INTERNAL VARIABLES"
2183 must not be URL percent encoded.
2186 For example, whether an hypothetical URL
2187 .Ql smtp://hey%3Ayou@our.house
2188 had been given that includes a user, or whether the URL was
2189 .Ql smtp://our.house
2190 and the user had been found differently, to lookup the variable chain
2191 .Va smtp-use-starttls
2192 \*(UA first looks for whether
2193 .Ql smtp-\:use-\:starttls-\:hey:you@our.house
2194 is defined, then whether
2195 .Ql smtp-\:use-\:starttls-\:our.house
2196 exists before finally ending up looking at the plain variable itself.
2199 \*(UA obeys the following logic scheme when dealing with the
2200 necessary credential information of an account:
2206 has been given in the URL the variables
2210 are looked up; if no such variable(s) can be found then \*(UA will,
2211 when enforced by the \*(OPal variables
2212 .Va netrc-lookup-HOST
2219 specific entry which provides a
2221 name: this lookup will only succeed if unambiguous (one possible matching
2224 It is possible to load encrypted
2229 If there is still no
2231 then \*(UA will fall back to the user who is supposed to run \*(UA,
2232 the identity of which has been fixated during \*(UA startup and is
2233 known to be a valid user on the current host.
2236 Authentication: unless otherwise noted this will lookup the
2237 .Va PROTOCOL-auth-USER@HOST , PROTOCOL-auth-HOST , PROTOCOL-auth
2238 variable chain, falling back to a protocol-specific default should this
2244 has been given in the URL, then if the
2246 has been found through the \*(OPal
2248 that may have already provided the password, too.
2249 Otherwise the variable chain
2250 .Va password-USER@HOST , password-HOST , password
2251 is looked up and used if existent.
2253 Afterwards the complete \*(OPal variable chain
2254 .Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup
2258 cache is searched for a password only (multiple user accounts for
2259 a single machine may exist as well as a fallback entry without user
2260 but with a password).
2262 If at that point there is still no password available, but the
2263 (protocols') chosen authentication type requires a password, then in
2264 interactive mode the user will be prompted on the terminal.
2269 S/MIME verification works relative to the values found in the
2273 header field(s), which means that the values of
2274 .Va smime-sign , smime-sign-cert , smime-sign-include-certs
2276 .Va smime-sign-message-digest
2277 will not be looked up using the
2281 chains from above but instead use the corresponding values from the
2282 message that is being worked on.
2283 In unusual cases multiple and different
2287 combinations may therefore be involved \(en on the other hand those
2288 unusual cases become possible.
2289 The usual case is as short as:
2292 .Dl set mta=smtp://USER:PASS@HOST smtp-use-starttls \e
2293 .Dl \ \ \ \ smime-sign smime-sign-cert=+smime.pair
2298 contains complete example configurations.
2301 .\" .Ss "On terminal control and line editor" {{{
2302 .Ss "On terminal control and line editor"
2304 \*(OP Terminal control will be realized through one of the standard
2306 libraries, either the
2308 or, alternatively, the
2310 both of which will be initialized to work with the environment variable
2312 Terminal control will enhance or enable interactive usage aspects, e.g.,
2313 .Sx "Coloured display" ,
2314 and extend behaviour of the Mailx-Line-Editor (MLE), which may learn the
2315 byte-sequences of keys like the cursor and function keys, and which will
2316 automatically enter the so-called
2318 alternative screen shall the terminal support it.
2319 The internal variable
2321 can be used to overwrite settings or to learn (correct(ed)) keycodes.
2322 Actual interaction with the chosen library can be disabled completely by
2323 setting the internal variable
2324 .Va termcap-disable ;
2326 will be queried regardless, even if the \*(OPal support for the
2327 libraries has not been enabled at configuration time.
2330 \*(OP The builtin \*(UA Mailx-Line-Editor (MLE) should work in all
2331 environments which comply to the ISO C standard
2333 and will support wide glyphs if possible (the necessary functionality
2334 had been removed from ISO C, but was included in
2336 Prevent usage of a line editor in interactive mode by setting the
2338 .Va line-editor-disable .
2339 Especially if the \*(OPal terminal control support is missing setting
2340 entries in the internal variable
2342 will help shall the MLE misbehave, see there for more.
2343 The MLE can support a little bit of
2349 feature is available then input from line editor prompts will be saved
2350 in a history list that can be searched in and be expanded from.
2351 Such saving can be prevented by prefixing input with any amount of
2353 Aspects of history, like allowed content and maximum size, as well as
2354 whether history shall be saved persistently, can be configured with the
2358 .Va history-gabby-persist
2363 The MLE supports a set of editing and control commands.
2364 By default (as) many (as possible) of these will be assigned to a set of
2365 single-letter control codes, which should work on any terminal (and can
2366 be generated by holding the
2368 key while pressing the key of desire, e.g.,
2372 command is available then the MLE commands can also be accessed freely
2373 by assigning the command name, which is shown in parenthesis in the list
2374 below, to any desired key-sequence, and the MLE will instead and also use
2376 to establish its builtin key bindings
2377 (more of them if the \*(OPal terminal control is available),
2378 an action which can then be suppressed completely by setting
2379 .Va line-editor-no-defaults .
2380 The following uses the
2382 ell-style quote notation that is documented in the introduction of
2384 combinations not mentioned either cause job control signals or do not
2385 generate a (unique) keycode:
2389 .Bl -tag -compact -width ".It Ql Ba"
2391 Go to the start of the line
2392 .Pf ( Cd mle-go-home ) .
2395 Move the cursor backward one character
2396 .Pf ( Cd mle-go-bwd ) .
2399 Forward delete the character under the cursor;
2400 quits \*(UA if used on the empty line unless the internal variable
2403 .Pf ( Cd mle-del-fwd ) .
2406 Go to the end of the line
2407 .Pf ( Cd mle-go-end ) .
2410 Move the cursor forward one character
2411 .Pf ( Cd mle-go-fwd ) .
2414 Cancel current operation, full reset.
2415 If there is an active history search or tabulator expansion then this
2416 command will first reset that, reverting to the former line content;
2417 thus a second reset is needed for a full reset in this case
2418 .Pf ( Cd mle-reset ) .
2421 Backspace: backward delete one character
2422 .Pf ( Cd mle-del-bwd ) .
2426 Horizontal tabulator:
2427 try to expand the word before the cursor, supporting the usual \*(UA
2429 .Sx "filename transformations" ,
2432 .Pf ( Cd mle-complete ) .
2434 .Cd mle-quote-rndtrip .
2438 commit the current line
2439 .Pf ( Cd mle-commit ) .
2442 Cut all characters from the cursor to the end of the line
2443 .Pf ( Cd mle-snarf-end ) .
2447 .Pf ( Cd mle-repaint ) .
2450 \*(OP Go to the next history entry
2451 .Pf ( Cd mle-hist-fwd ) .
2454 (\*(OPally context-dependent) Invokes the command
2458 \*(OP Go to the previous history entry
2459 .Pf ( Cd mle-hist-bwd ) .
2462 Toggle roundtrip mode shell quotes, where produced,
2464 .Pf ( Cd mle-quote-rndtrip ) .
2465 This setting is temporary, and will be forgotten once the command line
2469 \*(OP Complete the current line from (the remaining) older history entries
2470 .Pf ( Cd mle-hist-srch-bwd ) .
2473 \*(OP Complete the current line from (the remaining) newer history entries
2474 .Pf ( Cd mle-hist-srch-fwd ) .
2477 Paste the snarf buffer
2478 .Pf ( Cd mle-paste ) .
2485 .Pf ( Cd mle-snarf-line ) .
2488 Prompts for a Unicode character (its hexadecimal number) to be inserted
2489 .Pf ( Cd mle-prompt-char ) .
2490 Note this command needs to be assigned to a single-letter control code
2491 in order to become recognized and executed during input of
2492 a key-sequence (only three single-letter control codes can be used for
2493 that shortcut purpose); this control code is special-treated and cannot
2494 be part of any other sequence, because any occurrence will perform the
2496 function immediately.
2499 Cut the characters from the one preceding the cursor to the preceding
2501 .Pf ( Cd mle-snarf-word-bwd ) .
2504 Move the cursor forward one word boundary
2505 .Pf ( Cd mle-go-word-fwd ) .
2508 Move the cursor backward one word boundary
2509 .Pf ( Cd mle-go-word-bwd ) .
2512 Escape: reset a possibly used multibyte character input state machine
2513 and \*(OPally a lingering, incomplete key binding
2514 .Pf ( Cd mle-cancel ) .
2515 This command needs to be assigned to a single-letter control code in
2516 order to become recognized and executed during input of a key-sequence
2517 (only three single-letter control codes can be used for that shortcut
2519 This control code may also be part of a multi-byte sequence, but if
2520 a sequence is active and the very control code is currently also an
2521 expected input, then it will first be consumed by the active sequence.
2524 (\*(OPally context-dependent) Invokes the command
2528 (\*(OPally context-dependent) Invokes the command
2532 (\*(OPally context-dependent) Invokes the command
2536 Cut the characters from the one after the cursor to the succeeding word
2538 .Pf ( Cd mle-snarf-word-fwd ) .
2548 this will immediately reset a possibly active search etc.
2552 ring the audible bell.
2556 .\" .Ss "Coloured display" {{{
2557 .Ss "Coloured display"
2559 \*(OP \*(UA can be configured to support a coloured display and font
2560 attributes by emitting ANSI / ISO 6429 SGR (select graphic rendition)
2562 Usage of colours and font attributes solely depends upon the
2563 capability of the detected terminal type that is defined by the
2564 environment variable
2566 and which can be fine-tuned by the user via the internal variable
2570 On top of what \*(UA knows about the terminal the boolean variable
2572 defines whether the actually applicable colour and font attribute
2573 sequences should also be generated when output is going to be paged
2574 through the external program defined by the environment variable
2579 This is not enabled by default because different pager programs need
2580 different command line switches or other configuration in order to
2581 support those sequences.
2582 \*(UA however knows about some widely used pagers and in a clean
2583 environment it is often enough to simply set
2585 please refer to that variable for more on this topic.
2590 is set then any active usage of colour and font attribute sequences
2591 is suppressed, but without affecting possibly established
2596 To define and control colours and font attributes a single multiplexer
2597 command family exists:
2599 shows or defines colour mappings for the given colour type (e.g.,
2602 can be used to remove mappings of a given colour type.
2603 Since colours are only available in interactive mode, it may make
2604 sense to conditionalize the colour setup by encapsulating it with
2607 .Bd -literal -offset indent
2608 if terminal && $features =@ +colour
2609 colour iso view-msginfo ft=bold,fg=green
2610 colour iso view-header ft=bold,fg=red "from,subject"
2611 colour iso view-header fg=red
2613 uncolour iso view-header from,subject
2614 colour iso view-header ft=bold,fg=magenta,bg=cyan
2615 colour 256 view-header ft=bold,fg=208,bg=230 subject,from
2616 colour mono view-header ft=bold
2617 colour mono view-header ft=bold,ft=reverse subject,from
2621 .\" }}} (DESCRIPTION)
2624 .\" .Sh COMMANDS {{{
2627 Each command is typed on a line by itself,
2628 and may take arguments following the command word.
2629 Command names may be abbreviated, in which case the first command that
2630 matches the given prefix will be used.
2633 can be used to show the list of all commands, either alphabetically
2634 sorted or in prefix search order (these do not match, also because the
2635 POSIX standard prescribes a set of abbreviations).
2636 \*(OPally the command
2640 when given an argument, will show a documentation string for the
2641 command matching the expanded argument, as in
2643 which should be a shorthand of
2645 Both commands support a more
2647 listing mode which includes the argument type of the command.
2650 For commands which take message lists as arguments, the next message
2651 forward that satisfies the command's requirements will be used shall no
2652 explicit message list have been specified.
2653 If there are no messages forward of the current message,
2654 the search proceeds backwards,
2655 and if there are no good messages at all,
2656 \*(UA shows an error message and aborts the command.
2657 \*(ID Non-message-list arguments can be quoted using the following methods:
2660 .Bl -bullet -compact -offset indent
2662 An argument can be enclosed between paired double-quotes
2667 any white space, shell word expansion, or reverse solidus characters
2668 (except as described next) within the quotes are treated literally as
2669 part of the argument.
2670 A double-quote will be treated literally within single-quotes and vice
2672 Inside such a quoted string the actually used quote character can be
2673 used nonetheless by escaping it with a reverse solidus
2679 An argument that is not enclosed in quotes, as above, can usually still
2680 contain space characters if those spaces are reverse solidus escaped, as in
2684 A reverse solidus outside of the enclosing quotes is discarded
2685 and the following character is treated literally as part of the argument.
2690 Some commands which do not take message-list arguments can also be
2691 prefixed with the special keyword
2693 to choose \*(INible argument quoting rules, and some new commands only
2694 support the new rules (without that keyword) and are flagged \*(NQ.
2695 In the future \*(UA will (mostly) use
2697 compatible argument parsing:
2698 Non-message-list arguments can be quoted using the following shell-style
2699 mechanisms: the escape character, single-quotes, double-quotes and
2700 dollar-single-quotes; any unquoted number sign
2702 that parses as a new token starts a comment that ends argument processing.
2703 The overall granularity of error reporting and diagnostics, also
2704 regarding function arguments and their content, will improve.
2708 .Bl -bullet -compact -offset indent
2710 The literal value of any character can be preserved by preceding it
2711 with the escape character reverse solidus
2715 will cause variable expansion of the given name: \*(UA
2716 .Sx "INTERNAL VARIABLES"
2719 (shell) variables can be accessed through this mechanism, brace
2720 enclosing the name is supported.
2723 Arguments which are enclosed in
2724 .Ql 'single-\:quotes'
2725 retain their literal value.
2726 A single-quote cannot occur within single-quotes.
2729 The literal value of all characters enclosed in
2730 .Ql \(dqdouble-\:quotes\(dq
2731 is retained, with the exception of dollar
2733 which will cause variable expansion, as above, backquote (grave accent)
2735 (which not yet means anything special), reverse solidus
2737 which will escape any of the characters dollar
2739 (to prevent variable expansion), backquote (grave accent)
2743 (to prevent ending the quote) and reverse solidus
2745 (to prevent escaping, i.e., to embed a reverse solidus character as-is),
2746 but has no special meaning otherwise.
2749 Arguments enclosed in
2750 .Ql $'dollar-\:single-\:quotes'
2751 extend normal single quotes in that reverse solidus escape sequences are
2752 expanded as follows:
2754 .Bl -tag -compact -width "Ql \eNNN"
2760 an escape character.
2762 an escape character.
2774 emits a reverse solidus character.
2778 double quote (escaping is optional).
2780 eight-bit byte with the octal value
2782 (one to three octal digits), optionally prefixed by an additional
2784 A 0 byte will suppress further output for the quoted argument.
2786 eight-bit byte with the hexadecimal value
2788 (one or two hexadecimal characters).
2789 A 0 byte will suppress further output for the quoted argument.
2791 the Unicode / ISO-10646 character with the hexadecimal codepoint value
2793 (one to eight hexadecimal digits) \(em note that Unicode defines the
2794 maximum codepoint to be ever supported as
2799 This escape is only supported in locales which support Unicode (see
2800 .Sx "Character sets" ) ,
2801 in other cases the sequence will remain unexpanded unless the given code
2802 point is ASCII compatible or can be represented in the current locale.
2803 The character NUL will suppress further output for the quoted argument.
2807 except it takes only one to four hexadecimal digits.
2809 A mechanism that allows usage of the non-printable (ASCII and
2810 compatible) control codes 0 to 31: to create the printable
2811 representation of a control code the numeric value 64 is added, and the
2812 resulting ASCII character set code point is then printed, e.g., BEL is
2813 .Ql 7 + 64 = 71 = G .
2814 Whereas historically circumflex notation has often been used for
2815 visualization purposes of control codes, e.g.,
2817 the reverse solidus notation has been standardized:
2819 Some control codes also have standardized (ISO 10646, ISO C) alias
2820 representations, as shown above (e.g.,
2824 whenever such an alias exists \*(UA will use it for display purposes.
2825 The control code NUL
2827 ends argument processing without producing further output.
2829 Non-standard extension: expand the given variable name, as above.
2830 Brace enclosing the name is supported.
2832 Not yet supported, just to raise awareness: Non-standard extension.
2838 .Sy Compatibility notes:
2839 \*(ID Note these are new mechanisms which are not supported by all
2841 Round-tripping (feeding in things shown in list modes again) are not yet
2842 stable or possible at all.
2843 On new-style command lines it is wise to quote semicolon
2847 characters in order to ensure upward compatibility: the author would
2848 like to see things like
2849 .Ql ? echo $'trouble\etahead' | cat >> in_the_shell.txt
2851 .Ql ? top 2 5 10; type 3 22
2853 Before \*(UA will switch entirely to shell-style argument parsing there
2854 will be a transition phase where using
2856 will emit obsoletion warnings.
2858 .Bd -literal -offset indent
2859 echo 'Quotes '${HOME}' and 'tokens" differ!"# no comment
2860 echo Quotes ${HOME} and tokens differ! # comment
2861 echo Don"'"t you worry$'\ex21' The sun shines on us. $'\eu263A'
2865 In any event an unquoted reverse solidus at the end of a command line is
2866 discarded and the next line continues the command.
2867 \*(ID Note that line continuation is handled before the above parsing is
2868 applied, i.e., the parsers documented above will see merged lines.
2869 Filenames, where expected, and unless documented otherwise, are
2870 subsequently subjected to the following
2871 .Mx -ix "filename transformations"
2872 filename transformations, in sequence:
2875 .Bl -bullet -offset indent
2877 If the given name is a registered
2879 it will be replaced with the expanded shortcut.
2882 The filename is matched against the following patterns or strings:
2884 .Bl -hang -compact -width ".Ar %user"
2886 (Number sign) is expanded to the previous file.
2888 (Percent sign) is replaced by the invoking
2889 .Mx -ix "primary system mailbox"
2890 user's primary system mailbox, which either is the (itself expandable)
2892 if that is set, the standardized absolute pathname indicated by
2894 if that is set, or a builtin compile-time default otherwise.
2896 Expands to the primary system mailbox of
2898 (and never the value of
2900 regardless of its actual setting).
2902 (Ampersand) is replaced with the invoking users
2903 .Mx -ix "secondary mailbox"
2904 secondary mailbox, the
2911 directory (if that variable is set).
2913 Expands to the same value as
2915 but has special meaning for when used with, e.g., the command
2917 the file will be treated as a primary system mailbox by, e.g., the
2921 commands, meaning that messages that have been read in the current
2922 session will be moved to the
2924 mailbox instead of simply being flagged as read.
2928 Meta expansions are applied to the resulting filename: a leading tilde
2930 character will be replaced by the expansion of
2932 except when followed by a valid user name, in which case the home
2933 directory of the given user is used instead.
2938 will be replaced by the expansion of the variable, if possible; \*(UA
2939 .Sx "INTERNAL VARIABLES"
2942 (shell) variables can be accessed through this mechanism, and the usual
2943 escape mechanism has to be applied to prevent interpretation.
2944 If the fully expanded filename results in multiple pathnames and the
2945 command is expecting only one file, an error results.
2947 In interactive context, in order to allow simple value acceptance (via
2949 arguments will usually be displayed in a properly quoted form, e.g., a file
2950 .Ql diet\e is \ecurd.txt
2952 .Ql 'diet\e is \ecurd.txt' .
2957 The following commands are available:
2959 .Bl -tag -width ".It Ic BaNg"
2964 command which follows, replacing unescaped exclamation marks with the
2965 previously executed command if the internal variable
2971 The comment-command causes the entire line to be ignored.
2973 this really is a normal command which' purpose is to discard its
2976 indicating special character, which means that, e.g., trailing comments
2977 on a line are not possible.
2981 Goes to the next message in sequence and types it
2987 Display the preceding message, or the n'th previous message if given
2988 a numeric argument n.
2992 Show the current message number (the
2997 Show a brief summary of commands.
3000 output is available.
3001 \*(OP Given an argument a synopsis for the command in question is
3002 shown instead; commands can be abbreviated in general and this command
3003 can be used to see the full expansion of an abbreviation including the
3004 synopsis, try, e.g.,
3009 and see how the output changes.
3019 Interprets the remainder of the word as a macro name and passes it
3024 is a shorter synonym for
3025 .Ql call Ar mymacro .
3029 (ac) Creates, selects or lists (an) account(s).
3030 Accounts are special incarnations of
3032 macros and group commands and variable settings which together usually
3033 arrange the environment for the purpose of creating an email account.
3034 Different to normal macros settings which are covered by
3036 \(en here by default enabled! \(en will not be reverted before the
3041 (case-insensitive) always exists, and all but it can be deleted via
3044 Without arguments a listing of all defined accounts is shown.
3045 With one argument the given account is activated: the system
3047 of that account will be activated (as via
3049 and a possibly installed
3052 The two argument form is identical to defining a macro as via
3054 .Bd -literal -offset indent
3056 set folder=~/mail inbox=+syste.mbox record=+sent.mbox
3057 set from='myname@myisp.example (My Name)'
3058 set mta=smtp://mylogin@smtp.myisp.example
3064 (a) With no arguments, shows all currently-defined aliases.
3065 With one argument, shows that alias.
3066 With more than one argument,
3067 creates a new alias or appends to an existing one.
3069 can be used to delete aliases.
3073 (alt) Manage a list of alternate addresses / names of the active user,
3074 members of which will be removed from recipient lists when replying to
3077 variable is not set).
3078 If arguments are given the set of alternate names is replaced by them,
3079 without arguments the current set is displayed.
3083 Takes a message list and marks each message as having been answered.
3084 This mark has no technical meaning in the mail system;
3085 it just causes messages to be marked in the header summary,
3086 and makes them specially addressable.
3091 \*(OP\*(NQ The bind command extends the MLE (see
3092 .Sx "On terminal control and line editor" )
3093 with freely configurable key bindings.
3094 With one argument all bindings for the given context are shown,
3095 specifying an asterisk
3097 will show the bindings of all contexts; a more verbose listing will be
3098 produced if either of
3103 With two or more arguments a binding is (re)established:
3104 the first argument is the context to which the binding shall apply,
3105 the second argument is a comma-separated list of the
3107 which form the binding, and any remaining arguments form the expansion.
3108 To indicate that a binding shall not be auto-committed, but that the
3109 expansion shall instead be furtherly editable by the user, an at-sign
3111 (that will be removed) can be placed last in the expansion, from which
3112 leading and trailing whitespace will finally be removed.
3113 Reverse solidus cannot be used as the last character of expansion.
3116 Contexts define when a binding applies, i.e., a binding will not be seen
3117 unless the context for which it is defined for is currently active.
3118 This is not true for the shared binding
3120 which is the foundation for all other bindings and as such always
3121 applies, its bindings, however, only apply secondarily.
3122 The available contexts are the shared
3126 context which is used in all not otherwise documented situations, and
3128 which applies to compose mode only.
3132 which form the binding are specified as a comma-separated list of
3133 byte-sequences, where each list entry corresponds to one key(press).
3134 \*(OPally a list entry may, indicated by a leading colon character
3136 also refer to the name of a terminal capability;
3137 several dozen names will be compiled into \*(UA and may be specified
3140 or, if existing, by their
3142 name, regardless of the actually used terminal control library.
3143 It is however possible to use any capability, as long as the name is
3144 resolvable by the control library or defined in the internal variable
3146 Input sequences are not case-normalized, so that an exact match is
3147 required to update or remove a binding.
3150 .Bd -literal -offset indent
3151 bind base $'\eE',d mle-snarf-word-fwd # Esc(ape)
3152 bind base $'\eE',$'\ec?' mle-snarf-word-bwd # Esc, Delete
3153 bind default $'\ecA',:khome,w 'echo An editable binding@'
3154 bind default a,b,c rm -rf / @ # Another editable binding
3155 bind default :kf1 File %
3156 bind compose :kf1 ~e
3160 Note that the entire comma-separated list is first parsed (over) as a
3161 shell-token with whitespace as the field separator, before being parsed
3162 and expanded for real with comma as the field separator, therefore
3163 whitespace needs to be properly quoted:
3164 shell-style quoting is documented in the introduction of
3166 Using Unicode reverse solidus escape sequences renders a binding
3167 defunctional if the locale does not support Unicode (see
3168 .Sx "Character sets" ) ,
3169 and using terminal capabilities does so if no terminal control support
3170 is (currently) available.
3173 The following terminal capability names are builtin and can be used in
3175 or (if available) the two-letter
3177 notation regardless of the actually used library.
3178 See the respective manual for a list of capabilities.
3181 can be used to show all the capabilities of
3183 or the given terminal type;
3186 flag will also show supported (non-standard) extensions.
3189 .Bl -tag -compact -width kcuuf_or_kcuuf
3190 .It Cd kbs Ns \0or Cd kb
3192 .It Cd kdch1 Ns \0or Cd kD
3194 .It Cd kDC Ns \0or Cd *4
3195 \(em shifted variant.
3196 .It Cd kel Ns \0or Cd kE
3197 Clear to end of line.
3198 .It Cd kext Ns \0or Cd @9
3200 .It Cd kich1 Ns \0or Cd kI
3202 .It Cd kIC Ns \0or Cd #3
3203 \(em shifted variant.
3204 .It Cd khome Ns \0or Cd kh
3206 .It Cd kHOM Ns \0or Cd #2
3207 \(em shifted variant.
3208 .It Cd kend Ns \0or Cd @7
3210 .It Cd knp Ns \0or Cd kN
3212 .It Cd kpp Ns \0or Cd kP
3214 .It Cd kcub1 Ns \0or Cd kl
3215 Left cursor (with more modifiers: see below).
3216 .It Cd kLFT Ns \0or Cd #4
3217 \(em shifted variant.
3218 .It Cd kcuf1 Ns \0or Cd kr
3219 Right cursor (ditto).
3220 .It Cd kRIT Ns \0or Cd %i
3221 \(em shifted variant.
3222 .It Cd kcud1 Ns \0or Cd kd
3223 Down cursor (ditto).
3225 \(em shifted variant (only terminfo).
3226 .It Cd kcuu1 Ns \0or Cd ku
3229 \(em shifted variant (only terminfo).
3230 .It Cd kf0 Ns \0or Cd k0
3232 Add one for each function key up to
3237 .It Cd kf10 Ns \0or Cd k;
3239 .It Cd kf11 Ns \0or Cd F1
3241 Add one for each function key up to
3249 Some terminals support key-modifier combination extensions, e.g.,
3251 For example, the delete key,
3253 in its shifted variant, the name is mutated to
3255 then a number is appended for the states
3267 .Ql Shift+Alt+Control
3269 The same for the left cursor key,
3271 .Cd KLFT , KLFT3 , KLFT4 , KLFT5 , KLFT6 , KLFT7 , KLFT8 .
3274 Key bindings can be removed with the command
3276 It is advisable to use an initial escape or other control character (e.g.,
3278 for bindings which describe user key combinations (as opposed to purely
3279 terminal capability based ones), in order to avoid ambiguities whether
3280 input belongs to key sequences or not; it also reduces search time.
3283 may help shall keys and sequences be falsely recognized.
3288 Calls a macro that has been created via
3293 (ch) Change the working directory to
3295 or the given argument.
3301 \*(OP Only applicable to S/MIME signed messages.
3302 Takes a message list and a file name and saves the certificates
3303 contained within the message signatures to the named file in both
3304 human-readable and PEM format.
3305 The certificates can later be used to send encrypted messages to the
3306 respective message senders by setting
3307 .Va smime-encrypt-USER@HOST
3312 (ch) Change the working directory to
3314 or the given argument.
3320 Only applicable to threaded mode.
3321 Takes a message list and makes all replies to these messages invisible
3322 in header summaries, unless they are in state
3328 \*(OP\*(NQ Manage colour mappings of and for a
3329 .Sx "Coloured display" .
3330 The type of colour is given as the (case-insensitive) first argument,
3331 which must be one of
3333 for 256-colour terminals,
3338 for the standard 8-colour ANSI / ISO 6429 color palette and
3342 for monochrome terminals.
3343 Monochrome terminals cannot deal with colours, but only (some) font
3347 Without further arguments the list of all currently defined mappings
3348 for the given colour type is shown (as a special case giving
3352 will show the mappings of all types).
3353 Otherwise the second argument defines the mappable slot, and the third
3354 argument a (comma-separated list of) colour and font attribute
3355 specification(s), and the optional fourth argument can be used to
3356 specify a precondition: if conditioned mappings exist they are tested in
3357 (creation) order unless a (case-insensitive) match has been found, and
3358 the default mapping (if any has been established) will only be chosen as
3360 The types of precondition available depend on the mappable slot (see
3361 .Sx "Coloured display"
3362 for some examples), the following of which exist:
3365 Mappings prefixed with
3367 are used for the \*(OPal builtin Mailx-Line-Editor (MLE, see
3368 .Sx "On terminal control and line editor" )
3369 and do not support preconditions.
3371 .Bl -tag -compact -width view-partinfo
3373 This mapping is used for the position indicator that is visible when
3374 a line cannot be fully displayed on the screen.
3381 Mappings prefixed with
3383 are used in header summaries, and they all understand the preconditions
3385 (the current message) and
3387 for elder messages (only honoured in conjunction with
3388 .Va datefield-markout-older ) .
3390 .Bl -tag -compact -width view-partinfo
3392 This mapping is used for the
3394 that can be created with the
3398 formats of the variable
3401 For the complete header summary line except the
3403 and the thread structure.
3405 For the thread structure which can be created with the
3407 format of the variable
3412 Mappings prefixed with
3414 are used when displaying messages.
3416 .Bl -tag -compact -width view-partinfo
3418 This mapping is used for so-called
3420 lines, which are MBOX file format specific header lines.
3423 A comma-separated list of headers to which the mapping applies may be
3424 given as a precondition; if the \*(OPal regular expression support is
3425 available then if any of the
3427 (extended) regular expression characters is seen the precondition will
3428 be evaluated as (an extended) one.
3430 For the introductional message info line.
3431 .It Ar view-partinfo
3432 For MIME part info lines.
3436 The following (case-insensitive) colour definitions and font attributes
3437 are understood, multiple of which can be specified in a comma-separated
3447 It is possible (and often applicable) to specify multiple font
3448 attributes for a single mapping.
3451 foreground colour attribute:
3461 To specify a 256-color mode a decimal number colour specification in
3462 the range 0 to 255, inclusive, is supported, and interpreted as follows:
3464 .Bl -tag -compact -width "999 - 999"
3466 the standard ISO 6429 colors, as above.
3468 high intensity variants of the standard colors.
3470 216 colors in tuples of 6.
3472 grayscale from black to white in 24 steps.
3474 .Bd -literal -offset indent
3476 fg() { printf "\e033[38;5;${1}m($1)"; }
3477 bg() { printf "\e033[48;5;${1}m($1)"; }
3479 while [ $i -lt 256 ]; do fg $i; i=$(($i + 1)); done
3480 printf "\e033[0m\en"
3482 while [ $i -lt 256 ]; do bg $i; i=$(($i + 1)); done
3483 printf "\e033[0m\en"
3487 background colour attribute (see
3489 for possible values).
3493 Mappings may be removed with the command
3495 For a generic overview see the section
3496 .Sx "Coloured display" .
3501 (C) Copy messages to files whose names are derived from the author of
3502 the respective message and do not mark them as being saved;
3503 otherwise identical to
3508 (c) Copy messages to the named file and do not mark them as being saved;
3509 otherwise identical to
3514 Show the name of the current working directory.
3518 \*(OP For unencrypted messages this command is identical to
3520 Encrypted messages are first decrypted, if possible, and then copied.
3524 \*(OP For unencrypted messages this command is identical to
3526 Encrypted messages are first decrypted, if possible, and then copied.
3530 Without arguments the current list of macros, including their content,
3531 is shown, otherwise a macro is defined.
3532 A macro definition is a sequence of commands in the following form:
3533 .Bd -literal -offset indent
3542 A defined macro can be invoked explicitly by using the
3546 commands, or implicitly if a macro hook is triggered, e.g., a
3548 Note that interpretation of
3550 depends on how (i.e.,
3552 normal macro, folder hook, hook, account switch) the macro is invoked.
3553 Macros can be deleted via
3557 Macro behaviour, including option localization, will change in v15.
3558 Please be aware of that and possibly embed a version check in a resource
3563 (d) Marks the given message list as
3565 Deleted messages will neither be saved in
3567 nor will they be available for most other commands.
3573 Superseded by the multiplexer
3579 Deletes the current message and displays the next message.
3580 If there is no next message, \*(UA says
3587 up or down by one message when given
3591 argument, respectively.
3595 Takes a message list and marks each given message as a draft.
3596 This mark has no technical meaning in the mail system;
3597 it just causes messages to be marked in the header summary,
3598 and makes them specially addressable.
3602 \*(NQ (ec) Echoes its arguments to standard output after applying
3604 expansions and filename transformations, as documented for
3611 except that is echoes to standard error.
3615 (e) Point the text editor (as defined in
3617 at each message from the given list in turn.
3618 Modified contents are discarded unless the
3625 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3626 conditional \(em if the condition of a preceding
3628 was false, check the following condition and execute the following block
3629 if it evaluates true.
3634 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3635 conditional \(em if none of the conditions of the preceding
3639 commands was true, the
3645 (en) Marks the end of an
3646 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3647 conditional execution block.
3652 \*(NQ \*(UA has a strict notion about which variables are
3653 .Sx "INTERNAL VARIABLES"
3654 and which are managed in the program
3656 Since some of the latter are a vivid part of \*(UAs functioning,
3657 however, they are transparently integrated into the normal handling of
3658 internal variables via
3662 To integrate other environment variables of choice into this
3663 transparent handling, and also to export internal variables into the
3664 process environment where they normally are not, a
3666 needs to become established with this command, as in, e.g.,
3669 .Dl environ link PERL5LIB from TZ
3672 Afterwards changing such variables with
3674 will cause automatic updates of the program environment, and therefore
3675 be inherited by newly created child processes.
3676 Sufficient system support provided (it was in BSD as early as 1987, and
3677 is standardized since Y2K) removing such variables with
3679 will remove them also from the program environment, but in any way
3680 the knowledge they ever have been
3683 Note this implies that
3685 may cause loss of links.
3690 will remove an existing link, but leaves the variables as such intact.
3691 Additionally the subcommands
3695 are provided, which work exactly the same as the documented commands
3699 but (additionally) link the variable(s) with the program environment and
3700 thus immediately export them to, or remove them from (if possible),
3701 respectively, the program environment.
3706 \*(OP Since \*(UA uses the console as a user interface it can happen
3707 that messages scroll by too fast to become recognized.
3708 Optionally an error message ring queue is available which stores
3709 duplicates of any error message and notifies the user in interactive
3710 sessions whenever a new error has occurred.
3711 The queue is finite: if its maximum size is reached any new message
3712 replaces the eldest.
3715 can be used to manage this message queue: if given
3717 or no argument the queue will be displayed and cleared,
3719 will only clear all messages from the queue.
3723 (ex or x) Exit from \*(UA without changing the active mailbox and skip
3724 any saving of messages in
3726 as well as a possibly tracked line editor history file.
3732 but open the mailbox readonly.
3736 (fi) The file command switches to a new mailbox.
3737 Without arguments it shows status information of the current mailbox.
3738 If an argument is given, it will write out changes (such as deletions)
3739 the user has made and open a new mailbox.
3742 .Sx "filename transformations"
3743 are recognized for the
3745 argument, as documented in the introduction of
3749 If the name ends with
3754 it is treated as being compressed with
3759 respectively, and transparently handled through an intermediate
3760 (un)compression step (using a temporary file) with the according
3761 facility, sufficient support provided.
3762 Likewise, if the named file does not exist, but a file with one of the
3763 mentioned compression extensions does, then the name is automatically
3764 expanded and the compressed file is used.
3766 Otherwise, if the name ends with an extension for which
3767 .Va file-hook-load-EXTENSION
3769 .Va file-hook-save-EXTENSION
3770 variables are set, then the given hooks will be used to load and save
3772 and \*(UA will work with an intermediate temporary file.
3774 MBOX files (flat file-based mailboxes) are generally locked during file
3775 operations in order to avoid inconsistencies due to concurrent
3777 \*(OPal Mailbox files which \*(UA treats as the system
3782 .Sx "primary system mailbox" Ns
3783 es in general will also be protected by so-called dotlock files, the
3784 traditional way of mail spool file locking: for any file
3788 will be created for the duration of the synchronization \(em
3789 as necessary a privilege-separated dotlock child process will be used
3790 to accommodate for necessary privilege adjustments in order to create
3791 the dotlock file in the same directory
3792 and with the same user and group identities as the file of interest.
3796 refers to a directory with the subdirectories
3801 then it is treated as a folder in
3803 format; \*(ID the variable
3805 can be used to control the format of yet non-existent folders.
3808 .Dl \*(IN protocol://[user[:password]@]host[:port][/path]
3809 .Dl \*(OU protocol://[user@]host[:port][/path]
3811 is taken as an Internet mailbox specification.
3812 The \*(OPally supported protocols are
3816 (POP3 with SSL/TLS encrypted transport).
3819 part is valid only for IMAP; there it defaults to
3821 Also see the section
3822 .Sx "On URL syntax and credential lookup" .
3826 contains special characters, in particular
3830 they must be escaped in URL notation \(en the command
3832 can be used to show the necessary conversion.
3836 Takes a message list and marks the messages as
3838 ged for urgent/special attention.
3839 This mark has no technical meaning in the mail system;
3840 it just causes messages to be highlighted in the header summary,
3841 and makes them specially addressable.
3850 With no arguments, list the names of the folders in the folder directory.
3851 With an existing folder as an argument,
3852 lists the names of folders below the named folder.
3858 but saves the message in a file named after the local part of the first
3859 recipient's address (instead of in
3866 but saves the message in a file named after the local part of the first
3867 recipient's address (instead of in
3874 but responds to all recipients regardless of the
3879 .It Ic followupsender
3882 but responds to the sender only regardless of the
3898 (f) Takes a list of message specifications and displays a summary of
3899 their message headers, exactly as via
3901 An alias of this command is
3904 .Sx "Specifying messages" .
3910 but saves the message in a file named after the local part of the
3911 recipient's address (instead of in
3916 Takes a message and the address of a recipient
3917 and forwards the message to him.
3918 The text of the original message is included in the new one,
3919 with the value of the
3921 variable preceding it.
3922 To filter the included header fields to the desired subset use the
3924 slot of the white- and blacklisting command
3926 Only the first part of a multipart message is included unless
3927 .Va forward-as-attachment ,
3928 and recipient addresses will be stripped from comments, names etc.
3929 unless the internal variable
3935 \*(OB Superseded by the multiplexer
3940 \*(OB Superseded by the multiplexer
3945 Define or list command aliases, so-called ghosts.
3946 Without arguments a list of all currently known aliases is shown.
3947 With one argument the expansion of the given alias is shown.
3948 With two or more arguments a command alias is defined or updated: the
3949 first argument is the name under which the remaining command line should
3950 be accessible, the content of which can be just about anything.
3951 A ghost can be used everywhere a normal command can be used, but always
3952 takes precedence; any arguments that are given to the command alias are
3953 joined onto the alias content, and the resulting string forms the
3954 command line that is, in effect, executed.
3957 .Bd -literal -offset indent
3959 `ghost': no such alias: "xx"
3962 ghost xx "echo hello,"
3972 \*(NQ Multiplexer command to establish white- and blacklisting
3973 selections of header fields for a variety of applications.
3974 Without any arguments the entire set of known contexts and their current
3975 settings is displayed.
3976 When given arguments, the first argument is the context to which the
3977 command applies, one of (case-insensitively)
3979 for display purposes (via, e.g.,
3982 for selecting which headers shall be stored persistently when
3988 ing messages (note that MIME related etc. header fields should not be
3989 ignored in order to not destroy usability of the message in this case),
3991 for stripping down messages when
3993 ing message (has no effect if
3994 .Va forward-as-attachment
3997 for defining user-defined set of fields for the command
4001 The current settings of the given context are displayed if only the
4002 first argument is given.
4003 A second argument denotes the type of restriction that is to be chosen,
4004 it may be (a case-insensitive prefix of)
4008 for white- and blacklisting purposes, respectively.
4009 Establishing a whitelist suppresses inspection of the corresponding
4011 If no further argument is given the current settings of the given type
4015 With four or more arguments the third denotes the action to be applied,
4020 for addition of fields, and
4024 for removal of fields from the given type of the given context.
4025 The fourth, and any following arguments are expected to specify the
4026 fields of desire, or \*(OPally, regular expression matches ought to
4028 The special wildcard field (asterisk,
4030 will establish a (fast) shorthand setting which covers all fields, or
4031 remove all fields in one operation, respectively.
4036 (h) Show the current group of headers, the size of which depends on
4039 and the style of which can be adjusted with the variable
4041 If a message-specification is given the group of headers containing the
4042 first message therein is shown and the message at the top of the screen
4057 the list of history entries;
4060 argument selects and shows the respective history entry \(en
4063 to accept it, and the history entry will become the new history top.
4064 The default mode if no arguments are given is
4071 Takes a message list and marks each message therein to be saved in the
4076 Does not override the
4079 \*(UA deviates from the POSIX standard with this command, because a
4081 command issued after
4083 will display the following message, not the current one.
4088 (i) Part of the nestable
4089 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
4090 conditional execution construct \(em if the given condition is true then
4091 the encapsulated block is executed.
4092 POSIX only supports the (case-insensitive) conditions
4097 end, all remaining conditions are non-portable extensions; note that
4098 falsely specified conditions cause the execution of the entire
4099 conditional construct until the (matching) closing
4101 command to be suppressed.
4102 The syntax of the nestable
4104 conditional execution construct requires that each condition and syntax
4105 element is surrounded by whitespace.
4107 .Bd -literal -offset indent
4116 The (case-insensitive) condition
4118 erminal will evaluate to true if the standard input is a terminal, i.e.,
4119 in interactive sessions.
4120 Another condition can be any boolean value (see the section
4121 .Sx "INTERNAL VARIABLES"
4122 for textual boolean representations) to mark an enwrapped block as
4125 .Dq always execute .
4126 It is possible to check
4127 .Sx "INTERNAL VARIABLES"
4130 variables for existence or compare their expansion against a user given
4131 value or another variable by using the
4133 .Pf ( Dq variable next )
4134 conditional trigger character;
4135 a variable on the right hand side may be signalled using the same
4137 The variable names may be enclosed in a pair of matching braces.
4140 The available comparison operators are
4144 (less than or equal to),
4150 (greater than or equal to),
4154 (is substring of) and
4156 (is not substring of).
4157 The values of the left and right hand side are treated as strings and
4158 are compared 8-bit byte-wise, ignoring case according to the rules of
4159 the US-ASCII encoding (therefore, dependent on the active locale,
4160 possibly producing false results for strings in the locale encoding).
4161 Except for the substring checks the comparison will instead be performed
4162 arithmetically if both, the user given value as well as the variable
4163 content, can be parsed as numbers (integers).
4164 An unset variable is treated as the empty string.
4167 When the \*(OPal regular expression support is available, the additional
4173 They treat the right hand side as an extended regular expression that is
4174 matched case-insensitively and according to the active
4176 locale, meaning that strings in the locale encoding should be matched
4180 Conditions can be joined via AND-OR lists (where the AND operator is
4182 and the OR operator is
4184 which have equal precedence and will be evaluated with left
4185 associativity, thus using the same syntax that is known for the
4187 It is also possible to form groups of conditions and lists by enclosing
4188 them in pairs of brackets
4189 .Ql [\ \&.\&.\&.\ ] ,
4190 which may be interlocked within each other, and also be joined via
4194 The results of individual conditions and entire groups may be modified
4195 via unary operators: the unary operator
4197 will reverse the result.
4199 .Bd -literal -offset indent
4203 if $ttycharset == "UTF-8"
4204 echo *ttycharset* is set to UTF-8, case-insensitively
4208 echo These two variables are equal
4210 if $version-major >= 15
4211 echo Running a new version..
4212 if $features =@ +regex
4213 if $TERM =~ "^xterm\&.*"
4214 echo ..in an X terminal
4217 if [ [ true ] && [ [ ${debug} ] || [ $verbose ] ] ]
4220 if true && $debug || ${verbose}
4221 echo Left associativity, as is known from the shell
4223 if ! ! true && ! [ ! $debug && ! $verbose ]
4224 echo Unary operator support
4234 Superseded by the multiplexer
4239 Shows the names of all available commands, alphabetically sorted.
4240 If given any non-whitespace argument the list will be shown in the order
4241 in which command prefixes are searched.
4244 output is available.
4248 This command can be used to localize changes to variables, meaning that
4249 their state will be reverted to the former one once the covered scope
4251 It can only be used inside of macro definition blocks introduced by
4255 and is interpreted as a boolean (string, see
4256 .Sx "INTERNAL VARIABLES" ) ;
4259 of an account is left once it is switched off again.
4260 .Bd -literal -offset indent
4261 define temporary_settings {
4276 enables change localization and calls
4278 which explicitly resets localization, then any value changes within
4280 will still be reverted by
4282 \*(ID Once the outermost level, the one which enabled localization
4283 first, is left, but no earlier, all adjustments will be unrolled.
4284 \*(ID Likewise worth knowing, if in this example
4286 changes to a different
4288 which sets some variables that are yet covered by localizations, their
4289 scope will be extended, and in fact leaving the
4291 will (thus) restore settings in (likely) global scope which actually
4292 were defined in a local, private context.
4296 Reply to messages that come in via known
4299 .Pf ( Ic mlsubscribe )
4300 mailing lists, or pretend to do so (see
4301 .Sx "Mailing lists" ) :
4304 functionality this will actively resort and even remove message
4305 recipients in order to generate a message that is supposed to be sent to
4307 For example it will also implicitly generate a
4308 .Ql Mail-Followup-To:
4309 header if that seems useful, regardless of the setting of the variable
4316 but saves the message in a file named after the local part of the first
4317 recipient's address (instead of in
4322 (m) Takes a (list of) recipient address(es) as (an) argument(s),
4323 or asks on standard input if none were given;
4324 then collects the remaining mail content and sends it out.
4328 (mb) The given message list is to be sent to
4330 when \*(UA is quit; this is the default action unless the variable
4333 \*(ID This command can only be used in a
4335 .Sx "primary system mailbox" .
4339 Without any arguments the content of the MIME type cache will displayed.
4340 Otherwise each argument defines a complete MIME type specification of
4341 a type that shall be added (prepended) to the cache.
4342 In any event MIME type sources are loaded first as necessary \(en
4343 .Va mimetypes-load-control
4344 can be used to fine-tune which sources are actually loaded.
4345 Refer to the section on
4346 .Sx "The mime.types files"
4347 for more on MIME type specifications and this topic in general.
4348 MIME type unregistration and cache resets can be triggered with
4353 Without arguments the list of all currently defined mailing lists
4354 (and their attributes, if any) is shown; a more verbose listing will be
4355 produced if either of
4360 Otherwise all given arguments (which need not be quoted except for
4361 whitespace) will be added and henceforth be recognized as mailing lists.
4362 Mailing lists may be removed via the command
4365 If the \*(OPal regular expression support is available then mailing
4366 lists may also be specified as (extended) regular expressions (see
4372 Without arguments the list of all currently defined mailing lists which
4373 have a subscription attribute is shown; a more verbose listing will be
4374 produced if either of
4379 Otherwise this attribute will be set for all given mailing lists,
4380 newly creating them as necessary (as via
4382 Subscription attributes may be removed via the command
4391 but moves the messages to a file named after the local part of the
4392 sender address of the first message (instead of in
4399 but marks the messages for deletion if they were transferred
4406 but also displays header fields which would not pass the
4408 selection, and all MIME parts.
4416 on the given messages, even in non-interactive mode and as long as the
4417 standard output is a terminal.
4423 \*(OP When used without arguments or if
4425 has been given the content of the
4427 cache is shown, loading it first as necessary.
4430 then the cache will only be initialized and
4432 will remove its contents.
4433 Note that \*(UA will try to load the file only once, use
4434 .Ql Ic \&\&netrc Ns \:\0\:clear
4435 to unlock further attempts.
4440 .Sx "On URL syntax and credential lookup" ;
4442 .Sx "The .netrc file"
4443 documents the file format in detail.
4447 Checks for new mail in the current folder without committing any changes
4449 If new mail is present, a message is shown.
4453 the headers of each new message are also shown.
4454 This command is not available for all mailbox types.
4462 Goes to the next message in sequence and types it.
4463 With an argument list, types the next matching message.
4477 If the current folder is accessed via a network connection, a
4479 command is sent, otherwise no operation is performed.
4485 but also displays header fields which would not pass the
4487 selection, and all MIME parts.
4495 on the given messages, even in non-interactive mode and as long as the
4496 standard output is a terminal.
4504 but also pipes header fields which would not pass the
4506 selection, and all parts of MIME
4507 .Ql multipart/alternative
4512 (pi) Takes a message list and a shell command
4513 and pipes the messages through the command.
4514 Without an argument the current message is piped through the command
4521 every message is followed by a formfeed character.
4542 (q) Terminates the session, saving all undeleted, unsaved messages in
4545 preserving all messages marked with
4549 or never referenced in the system
4551 and removing all other messages from the
4553 .Sx "primary system mailbox" .
4554 If new mail has arrived during the session,
4556 .Dq You have new mail
4558 If given while editing a mailbox file with the command line flag
4560 then the edit file is rewritten.
4561 A return to the shell is effected,
4562 unless the rewrite of edit file fails,
4563 in which case the user can escape with the exit command.
4567 \*(NQ Read a line from standard input, and assign the splitted and
4568 trimmed line data to the given variables.
4569 If there are more fields than variables, assign successive fields to the
4570 last given variable.
4571 If there are less fields than variables, assign the empty string to the
4573 \*(ID This command will likely be extended towards more
4575 compatibility: for now splitting always occurs at whitespace, reverse
4576 solidus newline escaping is always supported, and the \*(OPal line
4577 editing features are always available when on an interactive terminal.
4578 .Bd -literal -offset indent
4581 ? echo "<$a> <$b> <$c>"
4597 Removes the named files or directories.
4598 If a name refer to a mailbox, e.g., a Maildir mailbox, then a mailbox
4599 type specific removal will be performed, deleting the complete mailbox.
4600 The user is asked for confirmation in interactive mode.
4604 Takes the name of an existing folder
4605 and the name for the new folder
4606 and renames the first to the second one.
4607 Both folders must be of the same type.
4611 (R) Reply to originator.
4612 Does not reply to other recipients of the original message.
4614 will exchange this command with
4616 Unless the internal variable
4618 is set the recipient address will be stripped from comments, names etc.
4622 (r) Take a message and group-responds to it by addressing the sender
4625 .Va followup-to-honour ,
4628 .Va recipients-in-cc
4629 influence response behaviour.
4632 offers special support for replying to mailing lists.
4633 Unless the internal variable
4635 is set recipient addresses will be stripped from comments, names etc.
4648 but initiates a group-reply regardless of the value of
4655 but responds to the sender only regardless of the value of
4662 but does not add any header lines.
4663 This is not a way to hide the sender's identity,
4664 but useful for sending a message again to the same recipients.
4668 Takes a list of messages and a user name
4669 and sends each message to the named user.
4671 and related header fields are prepended to the new copy of the message.
4689 .It Ic respondsender
4695 (ret) Superseded by the multiplexer
4702 but saves the messages in a file named after the local part of the
4703 sender of the first message instead of (in
4705 and) taking a filename argument.
4709 (s) Takes a message list and a filename and appends each message in turn
4710 to the end of the file.
4711 If no filename is given, the
4714 The filename in quotes, followed by the generated character count
4715 is echoed on the user's terminal.
4718 .Sx "primary system mailbox"
4719 the messages are marked for deletion.
4722 .Sx "filename transformations"
4723 are recognized, as documented in the introduction of
4728 \*(OB Superseded by the multiplexer
4733 \*(OB Superseded by the multiplexer
4738 \*(OB Superseded by the multiplexer
4743 Takes a message specification (list) and displays a header summary of
4744 all matching messages, as via
4746 This command is an alias of
4749 .Sx "Specifying messages" .
4753 Takes a message list and marks all messages as having been read.
4757 (se) Without arguments this command shows all internal variables which
4758 are currently known to \*(UA (they have been set).
4759 A more verbose listing will be produced if either of
4763 are set, in which case variables may be preceded with a comment line
4764 that gives some context of what \*(UA knows about the given variable.
4766 Otherwise the given variables (and arguments) are set or adjusted.
4767 Arguments are of the form
4769 (no space before or after
4773 if there is no value, i.e., a boolean variable.
4774 Quotation marks may be placed around any part of the assignment
4775 statement to quote blanks or tabs, e.g.,
4777 .Dl set indentprefix='->'
4779 If an argument begins with
4783 the effect is the same as invoking the
4785 command with the remaining part of the variable
4786 .Pf ( Ql unset save ) .
4790 that is known to map to an environment variable will automatically cause
4791 updates in the program environment (unsetting a variable in the
4792 environment requires corresponding system support).
4793 Please use the command
4795 for further environmental control.
4800 .Sx "INTERNAL VARIABLES"
4806 (sh) Invokes an interactive version of the shell.
4810 Without arguments the list of all currently defined shortcuts is
4812 Otherwise all given arguments (which need not be quoted except for
4813 whitespace) are treated as pairs of shortcuts and their expansions,
4814 creating new or changing already existing shortcuts, as necessary.
4815 Shortcuts may be removed via the command
4822 but performs neither MIME decoding nor decryption, so that the raw
4823 message text is shown.
4827 (si) Shows the size in characters of each message of the given
4832 Shows the current sorting criterion when used without an argument.
4833 Otherwise creates a sorted representation of the current folder,
4836 command and the addressing modes such that they refer to messages in
4838 Message numbers are the same as in regular mode.
4842 a header summary in the new order is also displayed.
4843 Automatic folder sorting can be enabled by setting the
4845 variable, as in, e.g.,
4846 .Ql set autosort=thread .
4847 Possible sorting criterions are:
4849 .Bl -tag -compact -width "subject"
4851 Sort the messages by their
4853 field, that is by the time they were sent.
4855 Sort messages by the value of their
4857 field, that is by the address of the sender.
4860 variable is set, the sender's real name (if any) is used.
4862 Sort the messages by their size.
4864 \*(OP Sort the message by their spam score, as has been classified by
4867 Sort the messages by their message status.
4869 Sort the messages by their subject.
4871 Create a threaded display.
4873 Sort messages by the value of their
4875 field, that is by the address of the recipient.
4878 variable is set, the recipient's real name (if any) is used.
4883 (so) The source command reads commands from the given file, which is
4884 subject to the usual filename expansions (see introductional words of
4886 If the given argument ends with a vertical bar
4888 then the argument will instead be interpreted as a shell command and
4889 \*(UA will read the output generated by it.
4890 Interpretation of commands read is stopped when an error is encountered.
4893 cannot be used from within macros that execute as
4894 .Va folder-hook Ns s
4897 i.e., it can only be called from macros that were
4904 (beside not supporting pipe syntax aka shell command input) is that
4905 this command will not generate an error if the given file argument
4906 cannot be opened successfully.
4910 \*(OP Takes a list of messages and clears their
4916 \*(OP Takes a list of messages and causes the
4918 to forget it has ever used them to train its Bayesian filter.
4919 Unless otherwise noted the
4921 flag of the message is inspected to chose whether a message shall be
4929 \*(OP Takes a list of messages and informs the Bayesian filter of the
4933 This also clears the
4935 flag of the messages in question.
4939 \*(OP Takes a list of messages and rates them using the configured
4940 .Va spam-interface ,
4941 without modifying the messages, but setting their
4943 flag as appropriate; because the spam rating headers are lost the rate
4944 will be forgotten once the mailbox is left.
4945 Refer to the manual section
4947 for the complete picture of spam handling in \*(UA.
4951 \*(OP Takes a list of messages and sets their
4957 \*(OP Takes a list of messages and informs the Bayesian filter of the
4963 flag of the messages in question.
4972 Create a threaded representation of the current folder,
4973 i.\|e. indent messages that are replies to other messages in the header
4974 display and change the
4976 command and the addressing modes such that they refer to messages in the
4978 Message numbers are the same as in unthreaded mode.
4982 a header summary in threaded order is also displayed.
4991 slot for white- and blacklisting header fields.
4995 (to) Takes a message list and types out the first
4997 lines of each message on the users' terminal.
4998 Unless a special selection has been established for the
5002 command, the only header fields that are displayed are
5013 It is possible to apply compression to what is displayed by setting
5015 Messages are decrypted and converted to the terminal character set
5020 (tou) Takes a message list and marks the messages for saving in
5022 \*(UA deviates from the POSIX standard with this command,
5025 command will display the following message instead of the current one.
5031 but also displays header fields which would not pass the
5033 selection, and all parts of MIME
5034 .Ql multipart/alternative
5039 (t) Takes a message list and types out each message on the users'
5043 For MIME multipart messages, all parts with a content type of
5047 are shown, the other are hidden except for their headers.
5048 Messages are decrypted and converted to the terminal character set
5053 Delete all given accounts.
5054 An error message is shown if a given account is not defined.
5057 will discard all existing accounts.
5061 (una) Takes a list of names defined by alias commands
5062 and discards the remembered groups of users.
5065 will discard all existing aliases.
5069 Takes a message list and marks each message as not having been answered.
5075 ing, specified by its context and input sequence, both of which may be
5076 specified as a wildcard (asterisk,
5080 will remove all bindings of all contexts.
5084 Only applicable to threaded mode.
5085 Takes a message list and makes the message and all replies to it visible
5086 in header summaries again.
5087 When a message becomes the current message,
5088 it is automatically made visible.
5089 Also when a message with collapsed replies is displayed,
5090 all of these are automatically uncollapsed.
5096 mapping for the given colour type (see
5098 for a list of types) and mapping; if the optional precondition argument
5099 is used then only the exact tuple of mapping and precondition is removed.
5102 will remove all mappings (no precondition allowed).
5104 .Sx "Coloured display"
5105 for the general picture.
5109 Undefine all given macros.
5110 An error message is shown if a given macro is not defined.
5113 will discard all existing macros.
5117 (u) Takes a message list and marks each message as not being deleted.
5121 Takes a message list and
5127 Takes a message list and marks each message as not being
5132 \*(OB Superseded by the multiplexer
5137 \*(OB Superseded by the multiplexer
5142 Remove all the given command
5146 will remove all ghosts.
5150 Superseded by the multiplexer
5155 Delete all given MIME types, e.g.,
5156 .Ql unmimetype text/plain
5157 will remove all registered specifications for the MIME type
5161 will discard all existing MIME types, just as will
5163 but which also reenables cache initialization via
5164 .Va mimetypes-load-control .
5168 Forget about all the given mailing lists.
5171 will remove all lists.
5176 .It Ic unmlsubscribe
5177 Remove the subscription attribute from all given mailing lists.
5180 will clear the attribute from all lists which have it set.
5191 Takes a message list and marks each message as not having been read.
5195 Superseded by the multiplexer
5200 \*(OB Superseded by the multiplexer
5205 \*(OB Superseded by the multiplexer
5210 (uns) Takes a list of internal variable names and discards their
5211 remembered values; the reverse of
5218 Deletes the shortcut names given as arguments.
5221 will remove all shortcuts.
5225 Disable sorted or threaded mode
5231 return to normal message order and,
5235 displays a header summary.
5245 Perform URL percent codec operations, rather according to RFC 3986,
5246 on all given strings.
5247 This is character set agnostic and thus locale dependent, and it may
5248 decode bytes which are invalid in the current locale, unless the input
5249 solely consists of characters in the portable character set, see
5250 .Sx "Character sets" .
5251 The first argument specifies the operation:
5255 perform plain URL percent en- and decoding, respectively.
5259 perform a slightly modified operation which should be better for
5260 pathnames: it does not allow a tilde
5262 and will neither accept hyphen
5266 as an initial character.
5270 Edit the values of or create the given variable(s) in the
5272 Boolean variables cannot be edited.
5276 This command produces the same output as the listing mode of
5280 ity adjustments, but only for the given variables.
5284 \*(OP Takes a message list and verifies each message.
5285 If a message is not a S/MIME signed message,
5286 verification will fail for it.
5287 The verification process checks if the message was signed using a valid
5289 if the message sender's email address matches one of those contained
5290 within the certificate,
5291 and if the message content has been altered.
5303 (v) Takes a message list and invokes the display editor on each message.
5304 Modified contents are discarded unless the
5310 (w) For conventional messages the body without all headers is written.
5311 The original message is never marked for deletion in the originating
5313 The output is decrypted and converted to its native format as necessary.
5314 If the output file exists, the text is appended.
5315 If a message is in MIME multipart format its first part is written to
5316 the specified file as for conventional messages, handling of the remains
5317 depends on the execution mode.
5318 No special handling of compressed files is performed.
5320 In interactive mode the user is consecutively asked for the filenames of
5321 the processed parts.
5322 For convience saving of each part may be skipped by giving an empty
5323 value, the same result as writing it to
5325 Shell piping the part content by specifying a leading vertical bar
5327 character for the filename is supported.
5328 Other user input is expanded as usually for folders, e.g., tilde
5329 expansion is performed, and contents of the destination file are
5330 overwritten if the file previously existed.
5332 \*(ID In non-interactive mode any part which does not specify a filename
5333 is ignored, and suspicious parts of filenames of the remaining parts are
5334 URL percent encoded (as via
5336 to prevent injection of malicious character sequences, resulting in
5337 a filename that will be written into the current directory.
5338 Existing files will not be overwritten, instead the part number or
5339 a dot are appended after a number sign
5341 to the name until file creation succeeds (or fails due to other
5351 \*(UA presents message headers in
5353 fuls as described under the
5356 Without arguments this command scrolls to the next window of messages,
5357 likewise if the argument is
5361 scrolls to the last,
5363 scrolls to the first, and
5368 A number argument prefixed by
5372 indicates that the window is calculated in relation to the current
5373 position, and a number without a prefix specifies an absolute position.
5379 but scrolls to the next or previous window that contains at least one
5388 .\" .Sh COMMAND ESCAPES {{{
5389 .Sh "COMMAND ESCAPES"
5391 Here is a summary of the command escapes available in compose mode,
5392 which are used to perform special functions when composing messages.
5393 Command escapes are only recognized at the beginning of lines.
5394 The actual escape character can be set via the internal variable
5396 it defaults to the tilde
5400 .Bl -tag -width ".It Ic BaNg"
5403 Insert the string of text in the message prefaced by a single
5405 (If the escape character has been changed,
5406 that character must be doubled
5407 in order to send it at the beginning of a line.)
5410 .It Ic ~! Ar command
5411 Execute the indicated shell
5413 which follows, replacing unescaped exclamation marks with the previously
5414 executed command if the internal variable
5416 is set, then return to the message.
5420 Same effect as typing the end-of-file character.
5423 .It Ic ~: Ar \*(UA-command Ns \0or Ic ~_ Ar \*(UA-command
5424 Execute the given \*(UA command.
5425 Not all commands, however, are allowed.
5429 Write a summary of command escapes.
5432 .It Ic ~< Ar filename
5437 .It Ic ~<! Ar command
5439 is executed using the shell.
5440 Its standard output is inserted into the message.
5443 .It Ic ~@ Op Ar filename...
5446 arguments are specified they are treated as a file list of
5450 arguments, optionally also separated by commas, which are expanded and
5451 then appended to the existing list of message attachments.
5452 It is not possible to add message attachments with this method, and
5453 (text) attachments are implicitly assumed to be in
5455 encoding, and will thus be evaluated as documented in the section
5456 .Sx "Character sets" .
5458 Without arguments, in non-interactive mode, for reproduceabilities sake,
5459 there will always be two questions for each attachment, regardless of
5460 whether character set conversion is available and what the file
5462 The first question expects the filename, and the second the the input
5463 character set to be passed through to the corresponding MIME parameter;
5464 no conversion will be tried if there is input to the latter question,
5465 otherwise the usual conversion algorithm as documented in
5466 .Sx "Character sets" ,
5468 For message attachments, the input to the second question is ignored.
5470 In interactive mode, without arguments, the attachment list is edited.
5471 If an attachment's file name is left empty,
5472 that attachment is deleted from the list.
5473 When the end of the attachment list is reached,
5474 \*(UA will ask for further attachments until an empty name is given.
5475 If a given file name solely consists of the number sign
5477 followed by a valid message number of the currently active mailbox, then
5478 the given message is attached as a MIME
5480 part and the rest of this section does not apply.
5482 If character set conversion has been compiled into \*(UA, then this mode
5483 gives the user the option to specify input and output character sets,
5484 unless the file extension indicates binary content, in which case \*(UA
5485 asks whether this step shall be skipped for the attachment in question.
5486 If not skipped, then the charset that succeeds to represent the
5487 attachment data will be used in the
5489 MIME parameter of the mail message:
5491 .Bl -bullet -compact
5493 If input and output character sets are specified, then the conversion is
5494 performed on the fly.
5495 The user will be asked repeatedly until the desired conversion succeeds.
5497 If only an output character set is specified, then the input is assumed
5500 charset and will be converted to the given output charset on the fly.
5501 The user will be asked repeatedly until the desired conversion succeeds.
5503 If no character sets are specified at all then the algorithm that is
5504 documented in the section
5505 .Sx "Character sets"
5506 is applied, but directly and on the fly.
5507 The user will be asked repeatedly until the desired conversion succeeds.
5509 Finally, if an input-, but no output character set is specified, then no
5510 conversion is ever performed, but the
5512 MIME parameter value will still be set to the user input.
5514 The character set selection loop can be left by typing
5516 i.e., causing an interrupt.
5517 .\" \*(OU next sentence
5518 Note that before \*(UA v15.0 this terminates the entire
5519 current attachment selection, not only the character set selection.
5522 Without character set conversion support, \*(UA will ask for the input
5523 character set only, and it will set the
5525 MIME parameter value to the given input, if any;
5526 if no user input is seen then the
5528 character set will be used for the parameter value instead.
5529 Note that the file extension check is not performed in this mode, since
5530 no conversion will take place anyway.
5534 Inserts the string contained in the
5537 .Ql Ic ~i Ns \0Sign ) .
5542 ting the variable(s) instead!) The escape sequences tabulator
5550 Inserts the string contained in the
5553 .Ql Ic ~i Ns \0sign ) .
5558 ting the variable(s) instead!) The escape sequences tabulator
5565 .It Ic ~b Ar name ...
5566 Add the given names to the list of blind carbon copy recipients.
5569 .It Ic ~c Ar name ...
5570 Add the given names to the list of carbon copy recipients.
5574 Read the file specified by the
5576 variable into the message.
5580 Invoke the text editor on the message collected so far.
5581 After the editing session is finished,
5582 the user may continue appending text to the message.
5585 .It Ic ~F Ar messages
5586 Read the named messages into the message being sent, including all
5587 message headers and MIME parts.
5588 If no messages are specified, read in the current message.
5591 .It Ic ~f Ar messages
5592 Read the named messages into the message being sent.
5593 If no messages are specified, read in the current message.
5594 Strips down the list of header fields according to the
5596 white- and blacklist selection of
5598 For MIME multipart messages,
5599 only the first displayable part is included.
5603 Edit the message header fields
5608 by typing each one in turn and allowing the user to edit the field.
5609 The default values for these fields originate from the
5617 Edit the message header fields
5623 by typing each one in turn and allowing the user to edit the field.
5626 .It Ic ~i Ar variable
5627 Insert the value of the specified variable into the message,
5628 adding a newline character at the end.
5629 The message remains unaltered if the variable is unset or empty.
5634 ting the variable(s) instead!) The escape sequences tabulator
5641 .It Ic ~M Ar messages
5642 Read the named messages into the message being sent,
5645 If no messages are specified, read the current message.
5648 .It Ic ~m Ar messages
5649 Read the named messages into the message being sent,
5652 If no messages are specified, read the current message.
5653 Strips down the list of header fields according to the
5655 white- and blacklist selection of
5657 For MIME multipart messages,
5658 only the first displayable part is included.
5662 Display the message collected so far,
5663 prefaced by the message header fields
5664 and followed by the attachment list, if any.
5668 Abort the message being sent,
5669 copying it to the file specified by the
5676 .It Ic ~R Ar filename
5677 Read the named file into the message, indented by
5681 .It Ic ~r Ar filename
5682 Read the named file into the message.
5686 Cause the named string to become the current subject field.
5687 Newline (NL) and carriage-return (CR) bytes are invalid and will be
5688 normalized to space (SP) characters.
5691 .It Ic ~t Ar name ...
5692 Add the given name(s) to the direct recipient list.
5695 .It Ic ~U Ar messages
5696 Read in the given / current message(s) excluding all headers, indented by
5700 .It Ic ~u Ar messages
5701 Read in the given / current message(s), excluding all headers.
5705 Invoke an alternate editor (defined by the
5707 environment variable) on the message collected so far.
5708 Usually, the alternate editor will be a screen editor.
5709 After the editor is quit,
5710 the user may resume appending text to the end of the message.
5713 .It Ic ~w Ar filename
5714 Write the message onto the named file.
5716 the message is appended to it.
5722 except that the message is not saved at all.
5725 .It Ic ~| Ar command
5726 Pipe the message through the specified filter command.
5727 If the command gives no output or terminates abnormally,
5728 retain the original text of the message.
5731 is often used as a rejustifying filter.
5735 .It Ic ~^ Op Ar cmd Op Ar subcmd Op Ar header-name Op Ar header-body
5736 Low-level command ment for scripted message access, i.e., for
5737 .Va on-compose-done-shell
5739 .Va on-compose-done .
5740 The used protocol is likely subject to changes, and therefore the
5741 mentioned hooks receive the used protocol version as an initial line.
5742 In general the first field of a response line represents a status code
5743 which specifies whether a command was successful or not, whether result
5744 data is to be expected, and if, the format of the result data.
5745 The status codes are:
5748 .Bl -tag -compact -width _210_
5750 Status ok; the remains of the line are the result.
5752 Status ok; the rest of the line is optionally used for more status.
5753 What follows are lines of result addresses, terminated by an empty line.
5754 The address lines consist of two fields, the first of which is the
5755 plain address, e.g.,
5757 separated by a single ASCII SP space from the second which contains the
5758 unstripped address, even if that is identical to the first field, e.g.,
5759 .Ql (Lovely) Bob <bob@exam.ple> .
5761 Status ok; the rest of the line is optionally used for more status.
5762 What follows are lines of furtherly unspecified string content,
5763 terminated by an empty line.
5765 Syntax error; invalid command.
5767 Syntax error in parameters or arguments.
5769 Error: an argument fails verification.
5770 For example an invalid address has been specified.
5772 Error: an otherwise valid argument is rendered invalid due to context.
5773 For example, a second address is added to a header which may consist of
5774 a single address only.
5778 If a command indicates failure then the message will have remained
5780 The following commands are supported:
5784 .Bl -tag -compact -width headers
5786 This command allows listing, inspection, and editing of message headers.
5787 The second argument specifies the subcommand to apply, one of:
5790 .Bl -tag -compact -width remove
5792 Without a third argument a list of all yet existing headers is given via
5794 this command is the default command of
5796 if no second argument has been given.
5797 A third argument restricts output to the given header only, which may
5800 if no such field is defined.
5803 Shows the content of the header given as the third argument.
5804 Dependent on the header type this may respond with
5808 any failure results in
5812 This will remove all instances of the header given as the third
5817 if no such header can be found.
5820 Create a new or an additional instance of the header given in the third
5821 argument, with the header body content as given in the fourth argument
5822 (the remains of the line).
5825 if the third argument specifies a free-form header field name that is
5826 invalid, or if body content extraction fails to succeed,
5828 if any extracted address does not pass syntax and/or security checks, and
5830 to indicate prevention of excessing a single-instance header \(em note that
5832 can be appended to (a space separator will be added automatically first).
5834 is returned upon success.
5843 .\" .Sh INTERNAL VARIABLES {{{
5844 .Sh "INTERNAL VARIABLES"
5846 Internal \*(UA variables are controlled via the
5850 commands; prefixing a variable name with the string
5854 has the same effect as using
5860 Creation or editing of variables can be performed in the
5865 will give more insight on the given variable(s), and
5867 when called without arguments, will show a listing of all variables.
5868 Both commands support a more
5871 Some well-known variables will also become inherited from the
5874 implicitly, others can be explicitly imported with the command
5876 and henceforth share the said properties.
5879 Two different kind of internal variables exist.
5880 There are boolean variables, which can only be in one of the two states
5884 and value variables with a(n optional) string value.
5885 For the latter proper quoting is necessary upon assignment time, the
5886 introduction of the section
5888 documents the supported quoting rules.
5890 .Bd -literal -offset indent
5891 wysh set one=val\e 1 two="val 2" \e
5892 three='val "3"' four=$'val \e'4\e''
5893 varshow one two three four
5894 unset one two three four
5898 Dependent upon the actual option the string values will be interpreted
5899 as numbers, colour names, normal text etc., but there also exists
5900 a special kind of string value, the
5901 .Dq boolean string ,
5902 which must either be a decimal integer (in which case
5906 and any other value is true) or any of the (case-insensitive) strings
5912 for a false boolean and
5918 for a true boolean; a special kind of boolean string is the
5920 which is a boolean string that can optionally be prefixed with the
5921 (case-insensitive) term
5925 which causes prompting of the user in interactive mode, with the given
5926 boolean as the default value.
5928 .\" .Ss "Initial settings" {{{
5929 .\" (Keep in SYNC: ./nail.h:okeys, ./nail.rc, ./nail.1:"Initial settings")
5930 .Ss "Initial Settings"
5932 The standard POSIX 2008/Cor 2-2016 mandates the following initial
5938 .Pf no Va autoprint ,
5952 .Pf no Va ignoreeof ,
5954 .Pf no Va keepsave ,
5956 .Pf no Va outfolder ,
5964 .Pf no Va sendwait ,
5973 Notes: \*(UA does not support the
5975 variable \(en use command line options or
5977 to pass options through to a
5979 And the default global
5981 file (which is loaded unless the
5983 command line flag has been used or the
5984 .Ev NAIL_NO_SYSTEM_RC
5985 environment variable is set) bends those initial settings a bit, e.g.,
5986 it sets the variables
5991 to name a few, establishes a default
5993 selection etc., and should thus be taken into account.
5996 .\" .Ss "Variables" {{{
5999 .Bl -tag -width ".It Va BaNg"
6001 .It Va -account-name
6002 \*(RO Is set to the active
6007 \*(RO The status of the last command.
6010 .It Va -folder-resolved
6011 \*(RO Set to the fully resolved path of
6013 once that evaluation has occurred; rather internal.
6016 .It Va -mailbox-display
6017 \*(RO The name of the current mailbox
6019 possibly abbreviated for display purposes.
6022 .It Va -mailbox-resolved
6023 \*(RO The fully resolved path of the current mailbox.
6026 .It Va add-file-recipients
6027 \*(BO When file or pipe recipients have been specified,
6028 mention them in the corresponding address fields of the message instead
6029 of silently stripping them from their recipient list.
6030 By default such addressees are not mentioned.
6034 \*(BO Causes only the local part to be evaluated
6035 when comparing addresses.
6039 \*(BO Causes messages saved in
6041 to be appended to the end rather than prepended.
6042 This should always be set.
6046 \*(BO Causes \*(UA to prompt for the subject of each message sent.
6047 If the user responds with simply a newline,
6048 no subject field will be sent.
6052 \*(BO Causes the prompts for
6056 lists to appear after the message has been edited.
6060 \*(BO If set, \*(UA asks for files to attach at the end of each message,
6061 shall the list be found empty at that time.
6062 An empty line finalizes the list.
6066 \*(BO Causes the user to be prompted for carbon copy recipients
6067 (at the end of each message if
6071 are set) shall the list be found empty (at that time).
6072 An empty line finalizes the list.
6076 \*(BO Causes the user to be prompted for blind carbon copy
6077 recipients (at the end of each message if
6081 are set) shall the list be found empty (at that time).
6082 An empty line finalizes the list.
6086 \*(BO\*(OP Causes the user to be prompted if the message is to be
6087 signed at the end of each message.
6090 variable is ignored when this variable is set.
6094 \*(BO Alternative name for
6101 .It Va attachment-ask-content-description , \
6102 attachment-ask-content-disposition , \
6103 attachment-ask-content-id , \
6104 attachment-ask-content-type
6105 \*(BO If set then the user will be prompted for some attachment
6106 information when editing the attachment list.
6107 It is advisable to not use these but for the first of the variables;
6108 even for that it has to be noted that the data is used
6114 A sequence of characters to display in the
6118 as shown in the display of
6120 each for one type of messages (see
6121 .Sx "Message states" ) ,
6122 with the default being
6125 .Ql NU\ \ *HMFAT+\-$~
6128 variable is set, in the following order:
6130 .Bl -tag -compact -width ".It Ql _"
6152 start of a collapsed thread.
6154 an uncollapsed thread (TODO ignored for now).
6158 classified as possible spam.
6164 Specifies a list of recipients to which a blind carbon copy of each
6165 outgoing message will be sent automatically.
6169 Specifies a list of recipients to which a carbon copy of each outgoing
6170 message will be sent automatically.
6174 \*(BO Causes threads to be collapsed automatically when threaded mode
6181 \*(BO Causes the delete command to behave like
6183 thus, after deleting a message the next one will be typed automatically.
6187 \*(BO\*(OB Causes threaded mode (see the
6189 command) to be entered automatically when a folder is opened.
6191 .Ql autosort=thread .
6195 Causes sorted mode (see the
6197 command) to be entered automatically with the value of this variable as
6198 sorting method when a folder is opened, e.g.,
6199 .Ql set autosort=thread .
6203 \*(BO Enables the substitution of all not (reverse-solidus) escaped
6206 characters by the contents of the last executed command for the
6208 shell escape command and
6210 one of the compose mode
6211 .Sx "COMMAND ESCAPES" .
6212 If this variable is not set no reverse solidus stripping is performed.
6215 .It Va batch-exit-on-error
6216 \*(BO If the batch mode has been enabled via the
6218 command line option, then this variable will be consulted whenever \*(UA
6219 completes one operation (returns to the command prompt); if it is set
6220 then \*(UA will terminate if the last operation generated an error.
6224 \*(OP Terminals generate multi-byte sequences for certain forms of
6225 input, for example for function and other special keys.
6226 Some terminals however do not write these multi-byte sequences as
6227 a whole, but byte-by-byte, and the latter is what \*(UA actually reads.
6228 This variable specifies the timeout in milliseconds that the MLE (see
6229 .Sx "On terminal control and line editor" )
6230 waits for more bytes to arrive unless it considers a sequence
6236 \*(BO Causes automatic display of a header summary after executing a
6238 command, and thus complements the standard variable
6240 which controls header summary display on program startup.
6241 It is only meaningful if
6247 \*(BO Sets some cosmetical features to traditional BSD style;
6248 has the same affect as setting
6250 and all other variables prefixed with
6252 it also changes the behaviour of
6254 (which does not exist in BSD).
6258 \*(BO Changes the letters shown in the first column of a header
6259 summary to traditional BSD style.
6263 \*(BO Changes the display of columns in a header summary to traditional
6268 \*(BO Changes some informational messages to traditional BSD style.
6274 field to appear immediately after the
6276 field in message headers and with the
6278 .Sx "COMMAND ESCAPES" .
6282 The value that should appear in the
6286 MIME header fields when no character set conversion of the message data
6288 This defaults to US-ASCII, and the chosen character set should be
6289 US-ASCII compatible.
6293 \*(OP The default 8-bit character set that is used as an implicit last
6294 member of the variable
6296 This defaults to UTF-8.
6297 If no character set conversion capabilities are available in \*(UA then
6298 the only supported character set is
6300 Refer to the section
6301 .Sx "Character sets"
6302 for the complete picture of character set conversion in \*(UA.
6305 .It Va charset-unknown-8bit
6306 \*(OP RFC 1428 specifies conditions when internet mail gateways shall
6308 the content of a mail message by using a character set with the name
6310 Because of the unclassified nature of this character set \*(UA will not
6311 be capable to convert this character set to any other character set.
6312 If this variable is set any message part which uses the character set
6314 is assumed to really be in the character set given in the value,
6315 otherwise the (final) value of
6317 is used for this purpose.
6319 This variable will also be taken into account if a MIME type (see
6320 .Sx "The mime.types files" )
6321 of a MIME message part that uses the
6323 character set is forcefully treated as text.
6327 The default value for the
6332 .It Va colour-disable
6333 \*(BO\*(OP Forcefully disable usage of colours.
6334 Also see the section
6335 .Sx "Coloured display" .
6339 \*(BO\*(OP Whether colour shall be used for output that is paged through
6341 Note that pagers may need special flags, e.g.,
6349 in order to support colours.
6350 Often doing manual adjustments is unnecessary since \*(UA may perform
6351 adjustments dependent on the value of the environment variable
6353 (see there for more).
6357 In a(n interactive) terminal session, then if this valued variable is
6358 set it will be used as a threshold to determine how many lines the given
6359 output has to span before it will be displayed via the configured
6363 can be forced by setting this to the value
6365 setting it without a value will deduce the current height of the
6366 terminal screen to compute the treshold (see
6374 Define a set of custom headers to be injected into newly composed or
6375 forwarded messages; it is also possible to create custom headers in
6378 which can be automated by setting one of the hooks
6379 .Va on-compose-done-shell
6381 .Va on-compose-done .
6382 The value is interpreted as a comma-separated list of custom headers to
6383 be injected, to include commas in the header bodies escape them with
6385 \*(ID Overwriting of automatically managed headers is neither supported
6388 .Dl set customhdr='Hdr1: Body1-1\e, Body1-2, Hdr2: Body2'
6394 the message date, if any is to be displayed according to the format of
6396 is by default taken from the
6398 line of the message.
6399 If this variable is set the date as given in the
6401 header field is used instead, converted to local time.
6402 To control the display format of the date assign a valid
6407 format should not be used, because \*(UA does not take embedded newlines
6408 into account when calculating how many lines fit onto the screen.)
6410 .Va datefield-markout-older .
6413 .It Va datefield-markout-older
6414 This variable, when set in addition to
6418 messages (concept is rather comparable to the
6420 option of the POSIX utility
6422 The content interpretation is identical to
6427 \*(BO Enables debug messages and obsoletion warnings, disables the
6428 actual delivery of messages and also implies
6434 .It Va disposition-notification-send
6436 .Ql Disposition-Notification-To:
6437 header (RFC 3798) with the message.
6441 .\" TODO .It Va disposition-notification-send-HOST
6443 .\".Va disposition-notification-send
6444 .\" for SMTP accounts on a specific host.
6445 .\" TODO .It Va disposition-notification-send-USER@HOST
6447 .\".Va disposition-notification-send
6448 .\"for a specific account.
6452 \*(BO When dot is set, a period
6454 on a line by itself during message input in (interactive) compose mode
6455 will be treated as end-of-message (in addition to the normal end-of-file
6464 .It Va dotlock-ignore-error
6465 \*(BO\*(OP Synchronization of mailboxes which \*(UA treats as
6467 .Sx "primary system mailbox" Ns
6468 es (see, e.g., the notes on
6470 .Sx "filename transformations"
6473 sections as well as the documentation of
6475 will be protected with so-called dotlock files\(emthe traditional mail
6476 spool file locking method\(emin addition to system file locking.
6477 Because \*(UA ships with a privilege-separated dotlock creation program
6478 that should always be able to create such a dotlock file there is no
6479 good reason to ignore dotlock file creation errors, and thus these are
6480 fatal unless this variable is set.
6484 \*(BO If this variable is set then the editor is started automatically
6485 when a message is composed in interactive mode, as if the
6487 .Sx "COMMAND ESCAPES"
6491 variable is implied for this automatically spawned editor session.
6495 \*(BO When a message is edited while being composed,
6496 its header is included in the editable text.
6506 fields are accepted within the header, other fields are ignored.
6510 \*(BO When entering interactive mode \*(UA normally writes
6511 .Dq \&No mail for user
6512 and exits immediately if a mailbox is empty or does not exist.
6513 If this variable is set \*(UA starts even with an empty or nonexistent
6514 mailbox (the latter behaviour furtherly depends upon
6521 .Ql Content-Transfer-Encoding
6522 to use in outgoing text messages and message parts, where applicable.
6523 (7-bit clean text messages are sent as-is, without a transfer encoding.)
6526 .Bl -tag -compact -width "_%%_"
6529 8-bit transport effectively causes the raw data be passed through
6530 unchanged, but may cause problems when transferring mail messages over
6531 channels that are not ESMTP (RFC 1869) compliant.
6532 Also, several input data constructs are not allowed by the
6533 specifications and may cause a different transfer-encoding to be used.
6534 .It Ql quoted-printable
6536 Quoted-printable encoding is 7-bit clean and has the property that ASCII
6537 characters are passed through unchanged, so that an english message can
6538 be read as-is; it is also acceptible for other single-byte locales that
6539 share many characters with ASCII, like, e.g., ISO-8859-1.
6540 The encoding will cause a large overhead for messages in other character
6541 sets: e.g., it will require up to twelve (12) bytes to encode a single
6542 UTF-8 character of four (4) bytes.
6544 .Pf (Or\0 Ql b64 . )
6545 The default encoding, it is 7-bit clean and will always be used for
6547 This encoding has a constant input:output ratio of 3:4, regardless of
6548 the character set of the input data it will encode three bytes of input
6549 to four bytes of output.
6550 This transfer-encoding is not human readable without performing
6556 If defined, the first character of the value of this variable
6557 gives the character to use in place of tilde
6560 .Sx "COMMAND ESCAPES" .
6561 If set to the empty string, command escapes are disabled.
6565 If not set then file and command pipeline targets are not allowed,
6566 and any such address will be filtered out, giving a warning message.
6567 If set without a value then all possible recipient address
6568 specifications will be accepted \(en see the section
6569 .Sx "On sending mail, and non-interactive mode"
6571 To accept them, but only in interactive mode, or when tilde commands
6572 were enabled explicitly by using one of the command line options
6576 set this to the (case-insensitive) value
6578 (note right now this is actually like setting
6579 .Ql restrict,-all,+name,+addr ) .
6581 In fact the value is interpreted as a comma-separated list of values.
6584 then the existence of disallowed specifications is treated as a hard
6585 send error instead of only filtering them out.
6586 The remaining values specify whether a specific type of recipient
6587 address specification is allowed (optionally indicated by a plus sign
6589 prefix) or disallowed (prefixed with a hyphen
6593 addresses all possible address specifications,
6597 command pipeline targets,
6599 plain user names and (MTA) aliases (\*(OB
6601 may be used as an alternative syntax to
6606 These kind of values are interpreted in the given order, so that
6607 .Ql restrict,\:fail,\:+file,\:-all,\:+addr
6608 will cause hard errors for any non-network address recipient address
6609 unless \*(UA is in interactive mode or has been started with the
6613 command line option; in the latter case(s) any address may be used, then.
6617 Unless this variable is set additional
6619 (Mail-Transfer-Agent)
6620 arguments from the command line, as can be given after a
6622 separator, are ignored due to safety reasons.
6623 However, if set to the special (case-insensitive) value
6625 then the presence of additional MTA arguments is treated as a hard
6626 error that causes \*(UA to exit with failure status.
6627 A lesser strict variant is the otherwise identical
6629 which does accept such arguments in interactive mode, or if tilde
6630 commands were enabled explicitly by using one of the command line options
6637 \*(RO String giving a list of features \*(UA, preceded with a plus-sign
6639 if the feature is available, and a minus-sign
6642 The output of the command
6644 will include this information.
6648 \*(BO This setting reverses the meanings of a set of reply commands,
6649 turning the lowercase variants, which by default address all recipients
6650 included in the header of a message
6651 .Pf ( Ic reply , respond , followup )
6652 into the uppercase variants, which by default address the sender only
6653 .Pf ( Ic Reply , Respond , Followup )
6656 .Ic replysender , respondsender , followupsender
6658 .Ic replyall , respondall , followupall
6659 are not affected by the current setting of
6664 .It Va file-hook-load-EXTENSION , file-hook-save-EXTENSION
6665 It is possible to install file hooks which will be used by the
6667 command in order to be able to transparently handle (through an
6668 intermediate temporary file) files with specific
6670 s: the variable values can include shell snippets and are expected to
6671 write data to standard output / read data from standard input,
6673 \*(ID The variables may not be changed while there is a mailbox
6675 .Bd -literal -offset indent
6676 set file-hook-load-xy='echo >&2 XY-LOAD; gzip -cd' \e
6677 file-hook-save-xy='echo >&2 XY-SAVE; gzip -c' \e
6678 record=+null-sent.xy
6683 The default path under which mailboxes are to be saved:
6684 file names that begin with the plus-sign
6686 will have the plus-sign replaced with the value of this variable if set,
6687 otherwise the plus-sign will remain unchanged when doing
6689 .Sx "filename transformations" ;
6690 see the introduction of
6692 as well as the documentation of
6694 for more on this topic.
6695 The value supports a subset of transformations itself, and if the
6696 non-empty value does not start with a solidus
6700 will be prefixed automatically.
6704 This variable can be set to the name of a
6706 macro which will be called whenever a
6709 The macro will also be invoked when new mail arrives,
6710 but message lists for commands executed from the macro
6711 only include newly arrived messages then.
6713 are activated by default in a folder hook, causing the covered settings
6714 to be reverted once the folder is left again.
6717 Macro behaviour, including option localization, will change in v15.
6718 Please be aware of that and possibly embed a version check in a resource
6722 .It Va folder-hook-FOLDER
6727 Unlike other folder specifications, the fully expanded name of a folder,
6728 without metacharacters, is used to avoid ambiguities.
6729 However, if the mailbox resides under
6733 specification is tried in addition, e.g., if
6737 (and thus relative to the user's home directory) then
6738 .Pa /home/usr1/mail/sent
6740 .Ql folder-hook-/home/usr1/mail/sent
6741 first, but then followed by
6742 .Ql folder-hook-+sent .
6746 \*(BO Controls whether a
6747 .Ql Mail-Followup-To:
6748 header is generated when sending messages to known mailing lists.
6750 .Va followup-to-honour
6752 .Ic mlist , mlsubscribe , reply
6757 .It Va followup-to-honour
6759 .Ql Mail-Followup-To:
6760 header is honoured when group-replying to a message via
6764 This is a quadoption; if set without a value it defaults to
6774 .It Va forward-as-attachment
6775 \*(BO Original messages are normally sent as inline text with the
6778 and only the first part of a multipart message is included.
6779 With this setting enabled messages are sent as unmodified MIME
6781 attachments with all of their parts included.
6785 The address (or a list of addresses) to put into the
6787 field of the message header, quoting RFC 5322:
6788 the author(s) of the message, that is, the mailbox(es) of the person(s)
6789 or system(s) responsible for the writing of the message.
6792 ing to messages these addresses are handled as if they were in the
6796 If the machine's hostname is not valid at the Internet (for example at
6797 a dialup machine) then either this variable or
6799 (\*(IN and with a defined SMTP protocol in
6802 adds even more fine-tuning capabilities),
6806 contains more than one address,
6809 variable is required (according to the standard RFC 5322).
6811 If a file-based MTA is used, then
6813 (or, if that contains multiple addresses,
6815 can nonetheless be enforced to appear as the envelope sender address at
6816 the MTA protocol level (the RFC 5321 reverse-path), either by using the
6818 command line option (with an empty argument; see there for the complete
6819 picture on this topic), or by setting the internal variable
6820 .Va r-option-implicit .
6824 \*(BO When replying to or forwarding a message \*(UA normally removes
6825 the comment and name parts of email addresses.
6826 If this variable is set such stripping is not performed,
6827 and comments, names etc. are retained.
6831 The string to put before the text of a message with the
6835 .Va forward-as-attachment
6838 .Dq -------- Original Message --------
6839 if unset; No heading is put if it is set to the empty string.
6843 \*(BO Causes the header summary to be written at startup and after
6844 commands that affect the number of messages or the order of messages in
6845 the current folder; enabled by default.
6846 The command line option
6852 complements this and controls header summary display on folder changes.
6857 A format string to use for the summary of
6859 similar to the ones used for
6862 Format specifiers in the given string start with a percent character
6864 and may be followed by an optional decimal number indicating the field
6865 width \(em if that is negative, the field is to be left-aligned.
6866 Valid format specifiers are:
6869 .Bl -tag -compact -width "_%%_"
6871 A plain percent character.
6874 a space character but for the current message
6876 for which it expands to
6880 a space character but for the current message
6882 for which it expands to
6885 \*(OP The spam score of the message, as has been classified via the
6888 Shows only a replacement character if there is no spam support.
6890 Message attribute character (status flag); the actual content can be
6894 The date when the message was received, or the date found in the
6898 variable is set (optionally to a date display format string).
6900 The indenting level in threaded mode.
6902 The address of the message sender.
6904 The message thread tree structure.
6905 (Note that this format does not support a field width.)
6907 The number of lines of the message, if available.
6911 The number of octets (bytes) in the message, if available.
6913 Message subject (if any).
6915 Message subject (if any) in double quotes.
6917 Message recipient flags: is the addressee of the message a known or
6918 subscribed mailing list \(en see
6923 The position in threaded/sorted order.
6927 .Ql %>\&%a\&%m\ %-18f\ %16d\ %4l/%\-5o\ %i%-s ,
6929 .Ql %>\&%a\&%m\ %20-f\ \ %16d\ %3l/%\-5o\ %i%-S
6940 .It Va headline-bidi
6941 Bidirectional text requires special treatment when displaying headers,
6942 because numbers (in dates or for file sizes etc.) will not affect the
6943 current text direction, in effect resulting in ugly line layouts when
6944 arabic or other right-to-left text is to be displayed.
6945 On the other hand only a minority of terminals is capable to correctly
6946 handle direction changes, so that user interaction is necessary for
6948 Note that extended host system support is required nonetheless, e.g.,
6949 detection of the terminal character set is one precondition;
6950 and this feature only works in an Unicode (i.e., UTF-8) locale.
6952 In general setting this variable will cause \*(UA to encapsulate text
6953 fields that may occur when displaying
6955 (and some other fields, like dynamic expansions in
6957 with special Unicode control sequences;
6958 it is possible to fine-tune the terminal support level by assigning
6960 no value (or any value other than
6965 will make \*(UA assume that the terminal is capable to properly deal
6966 with Unicode version 6.3, in which case text is embedded in a pair of
6967 U+2068 (FIRST STRONG ISOLATE) and U+2069 (POP DIRECTIONAL ISOLATE)
6969 In addition no space on the line is reserved for these characters.
6971 Weaker support is chosen by using the value
6973 (Unicode 6.3, but reserve the room of two spaces for writing the control
6974 sequences onto the line).
6979 select Unicode 1.1 support (U+200E, LEFT-TO-RIGHT MARK); the latter
6980 again reserves room for two spaces in addition.
6984 \*(OP If a line editor is available then this can be set to
6985 name the (expandable) path of the location of a permanent history file.
6988 .It Va history-gabby
6989 \*(BO\*(OP Add more entries to the history as is normally done.
6992 .It Va history-gabby-persist
6993 \*(BO\*(OP \*(UA's own MLE will not save the additional
6995 entries in persistent storage unless this variable is set.
6996 On the other hand it will not loose the knowledge of whether
6997 a persistent entry was gabby or not.
7003 \*(OP If a line editor is available this value restricts the
7004 amount of history entries that are saved into a set and valid
7006 A value of less than 0 disables this feature;
7007 note that loading and incorporation of
7009 upon program startup can also be suppressed by doing this.
7010 If unset or 0, a default value will be used.
7011 Dependent on the available line editor this will also define the
7012 number of history entries in memory;
7013 it is also editor-specific whether runtime updates of this value will
7018 \*(BO This setting controls whether messages are held in the system
7020 and it is set by default.
7024 Use this string as hostname when expanding local addresses instead of
7025 the value obtained from
7034 Note that when SMTP transport is not used (via
7036 then it is normally the responsibility of the MTA to create these
7037 fields, \*(IN in conjunction with SMTP however
7039 also influences the results:
7040 you should produce some test messages with the desired combination of
7049 \*(BO\*(OP Can be used to turn off the automatic conversion of domain
7050 names according to the rules of IDNA (internationalized domain names
7052 Since the IDNA code assumes that domain names are specified with the
7054 character set, an UTF-8 locale charset is required to represent all
7055 possible international domain names (before conversion, that is).
7059 \*(BO Ignore interrupt signals from the terminal while entering
7060 messages; instead echo them as
7062 characters and discard the current line.
7066 \*(BO Ignore end-of-file conditions
7067 .Pf ( Ql control-D )
7068 in compose mode on message input and in interactive command input.
7069 If set an interactive command input session can only be left by
7070 explicitly using one of the commands
7074 and message input in compose mode can only be terminated by entering
7077 on a line by itself or by using the
7079 .Sx "COMMAND ESCAPES" ;
7081 overrides a setting of
7086 If this is set to a non-empty string it will specify the users
7088 .Sx "primary system mailbox" ,
7091 and the system-dependent default, and (thus) be used to replace
7095 .Sx "filename transformations" ;
7096 see the introduction of
7098 as well as the command
7100 for more on this topic.
7101 The value supports a subset of transformations itself.
7109 .Sx "COMMAND ESCAPES"
7112 option for indenting messages,
7113 in place of the normal tabulator character
7115 which is the default.
7116 Be sure to quote the value if it contains spaces or tabs.
7120 \*(BO If set, an empty system (MBOX) mailbox file is not removed.
7121 Note that, in conjunction with
7124 .Ev POSIXLY_CORRECT )
7125 any empty file will be removed unless this variable is set.
7126 This may improve the interoperability with other mail user agents
7127 when using a common folder directory, and prevents malicious users
7128 from creating fake mailboxes in a world-writable spool directory.
7129 \*(ID Only local regular (MBOX) files are covered, Maildir or other
7130 mailbox types will never be removed, even if empty.
7133 .It Va keep-content-length
7134 \*(BO When (editing messages and) writing
7136 mailbox files \*(UA can be told to keep the
7140 header fields that some MUAs generate by setting this variable.
7141 Since \*(UA does neither use nor update these non-standardized header
7142 fields (which in itself shows one of their conceptual problems),
7143 stripping them should increase interoperability in between MUAs that
7144 work with with same mailbox files.
7145 Note that, if this is not set but
7146 .Va writebackedited ,
7147 as below, is, a possibly performed automatic stripping of these header
7148 fields already marks the message as being modified.
7152 \*(BO When a message is saved it is usually discarded from the
7153 originating folder when \*(UA is quit.
7154 This setting causes all saved message to be retained.
7157 .It Va line-editor-disable
7158 \*(BO Turn off any enhanced line editing capabilities (see
7159 .Sx "On terminal control and line editor"
7163 .It Va line-editor-no-defaults
7164 \*(BO\*(OP Do not establish any default key binding.
7168 \*(BO When a message is replied to and this variable is set,
7169 it is marked as having been answered.
7170 This mark has no technical meaning in the mail system;
7171 it just causes messages to be marked in the header summary,
7172 and makes them specially addressable.
7176 \*(BO Internal development variable.
7179 .It Va message-id-disable
7180 \*(BO By setting this variable the generation of
7182 can be completely suppressed, effectively leaving this task up to the
7184 (Mail-Transfer-Agent) or the SMTP server.
7185 (According to RFC 5321 your SMTP server is not required to add this
7186 field by itself, so you should ensure that it accepts messages without a
7190 .It Va message-inject-head
7191 A string to put at the beginning of each new message.
7192 The escape sequences tabulator
7199 .It Va message-inject-tail
7200 A string to put at the end of each new message.
7201 The escape sequences tabulator
7209 \*(BO Usually, when an
7211 expansion contains the sender, the sender is removed from the expansion.
7212 Setting this option suppresses these removals.
7217 option to be passed through to the
7219 (Mail-Transfer-Agent); though most of the modern MTAs no longer document
7220 this flag, no MTA is known which does not support it (for historical
7224 .It Va mime-allow-text-controls
7225 \*(BO When sending messages, each part of the message is MIME-inspected
7226 in order to classify the
7229 .Ql Content-Transfer-Encoding:
7232 that is required to send this part over mail transport, i.e.,
7233 a computation rather similar to what the
7235 command produces when used with the
7239 This classification however treats text files which are encoded in
7240 UTF-16 (seen for HTML files) and similar character sets as binary
7241 octet-streams, forcefully changing any
7246 .Ql application/octet-stream :
7247 If that actually happens a yet unset charset MIME parameter is set to
7249 effectively making it impossible for the receiving MUA to automatically
7250 interpret the contents of the part.
7252 If this variable is set, and the data was unambiguously identified as
7253 text data at first glance (by a
7257 file extension), then the original
7259 will not be overwritten.
7262 .It Va mime-alternative-favour-rich
7263 \*(BO If this variable is set then rich MIME alternative parts (e.g.,
7264 HTML) will be preferred in favour of included plain text versions when
7265 displaying messages, provided that a handler exists which produces
7266 output that can be (re)integrated into \*(UA's normal visual display.
7267 (E.g., at the time of this writing some newsletters ship their full
7268 content only in the rich HTML part, whereas the plain text part only
7269 contains topic subjects.)
7272 .It Va mime-counter-evidence
7275 field is used to decide how to handle MIME parts.
7276 Some MUAs however do not use
7278 or a similar mechanism to correctly classify content, but simply specify
7279 .Ql application/octet-stream ,
7280 even for plain text attachments like
7282 If this variable is set then \*(UA will try to classify such MIME
7283 message parts on its own, if possible, for example via a possibly
7284 existing attachment filename.
7285 A non-empty value may also be given, in which case a number is expected,
7286 actually a carrier of bits.
7287 Creating the bit-carrying number is a simple addition:
7288 .Bd -literal -offset indent
7289 ? !echo Value should be set to $((2 + 4 + 8))
7290 Value should be set to 14
7293 .Bl -bullet -compact
7295 If bit two is set (2) then the detected
7297 content-type will be carried along with the message and be used for
7299 .Va pipe-TYPE/SUBTYPE
7300 is responsible for the MIME part, shall that question arise;
7301 when displaying such a MIME part the part-info will indicate the
7302 overridden content-type by showing a plus-sign
7305 If bit three is set (4) then the counter-evidence is always produced
7306 and a positive result will be used as the MIME type, even forcefully
7307 overriding the parts given MIME type.
7309 If bit four is set (8) then as a last resort the actual content of
7310 .Ql application/octet-stream
7311 parts will be inspected, so that data which looks like plain text can be
7316 .It Va mimetypes-load-control
7317 Can be used to control which of the
7319 databases are loaded by \*(UA, as furtherly described in the section
7320 .Sx "The mime.types files" .
7323 is part of the option value, then the user's personal
7325 file will be loaded (if it exists); likewise the letter
7327 controls loading of the system wide
7328 .Pa /etc/mime.types ;
7329 directives found in the user file take precedence, letter matching is
7331 If this variable is not set \*(UA will try to load both files.
7332 Incorporation of the \*(UA-builtin MIME types cannot be suppressed,
7333 but they will be matched last (the order can be listed via
7336 More sources can be specified by using a different syntax: if the
7337 value string contains an equals sign
7339 then it is instead parsed as a comma-separated list of the described
7342 pairs; the given filenames will be expanded and loaded, and their
7343 content may use the extended syntax that is described in the section
7344 .Sx "The mime.types files" .
7345 Directives found in such files always take precedence (are prepended to
7346 the MIME type cache).
7351 To choose an alternate Mail-Transfer-Agent, set this option to either
7352 the full pathname of an executable (optionally prefixed with a
7354 protocol indicator), or \*(OPally a SMTP protocol URL, e.g., \*(IN
7356 .Dl smtps?://[user[:password]@]server[:port]
7359 .Ql [smtp://]server[:port] . )
7360 The default has been chosen at compie time.
7361 All supported data transfers are executed in child processes, which
7362 run asynchronously, and without supervision, unless either the
7367 If such a child receives a TERM signal, it will abort and
7374 For a file-based MTA it may be necessary to set
7376 in in order to choose the right target of a modern
7379 It will be passed command line arguments from several possible sources:
7382 if set, from the command line if given and the variable
7385 Argument processing of the MTA will be terminated with a
7390 The otherwise occurring implicit usage of the following MTA command
7391 line arguments can be disabled by setting the boolean variable
7392 .Va mta-no-default-arguments
7393 (which will also disable passing
7397 (for not treating a line with only a dot
7399 character as the end of input),
7407 variable is set); in conjunction with the
7409 command line option \*(UA will also (not) pass
7415 \*(OP \*(UA can send mail over SMTP network connections to a single
7416 defined SMTP smarthost, the access URL of which has to be assigned to
7418 To use this mode it is helpful to read
7419 .Sx "On URL syntax and credential lookup" .
7420 It may be necessary to set the
7422 variable in order to use a specific combination of
7427 with some mail providers.
7430 .Bl -bullet -compact
7432 The plain SMTP protocol (RFC 5321) that normally lives on the
7433 server port 25 and requires setting the
7434 .Va smtp-use-starttls
7435 variable to enter a SSL/TLS encrypted session state.
7436 Assign a value like \*(IN
7437 .Ql smtp://[user[:password]@]server[:port]
7439 .Ql smtp://server[:port] )
7440 to choose this protocol.
7442 The so-called SMTPS which is supposed to live on server port 465
7443 and is automatically SSL/TLS secured.
7444 Unfortunately it never became a standardized protocol and may thus not
7445 be supported by your hosts network service database
7446 \(en in fact the port number has already been reassigned to other
7449 SMTPS is nonetheless a commonly offered protocol and thus can be
7450 chosen by assigning a value like \*(IN
7451 .Ql smtps://[user[:password]@]server[:port]
7453 .Ql smtps://server[:port] ) ;
7454 due to the mentioned problems it is usually necessary to explicitly
7459 Finally there is the SUBMISSION protocol (RFC 6409), which usually
7460 lives on server port 587 and is practically identically to the SMTP
7461 protocol from \*(UA's point of view beside that; it requires setting the
7462 .Va smtp-use-starttls
7463 variable to enter a SSL/TLS secured session state.
7464 Assign a value like \*(IN
7465 .Ql submission://[user[:password]@]server[:port]
7467 .Ql submission://server[:port] ) .
7472 .It Va mta-arguments
7473 Arguments to pass through to a file-based
7475 can be given via this variable, the content of which will be split up in
7476 a vector of arguments, to be joined onto other possible MTA options:
7478 .Dl set mta-arguments='-t -X \&"/tmp/my log\&"'
7481 .It Va mta-no-default-arguments
7482 \*(BO Unless this variable is set \*(UA will pass some well known
7483 standard command line options to a file-based
7485 (Mail-Transfer-Agent), see there for more.
7489 Many systems use a so-called
7491 environment to ensure compatibility with
7493 This works by inspecting the name that was used to invoke the mail
7495 If this variable is set then the mailwrapper (the program that is
7496 actually executed when calling the file-based
7498 will treat its contents as that name.
7503 .It Va NAIL_EXTRA_RC
7504 The name of an optional startup file to be read last.
7505 This variable has an effect only if it is set in any of the
7506 .Sx "Resource files" ,
7507 it is not imported from the environment.
7508 Use this file for commands that are not understood by other POSIX
7513 .It Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup
7514 \*(BO\*(IN\*(OP Used to control usage of the users
7516 file for lookup of account credentials, as documented in the section
7517 .Sx "On URL syntax and credential lookup"
7521 .Sx "The .netrc file"
7522 documents the file format.
7534 then \*(UA will read the output of a shell pipe instead of the users
7536 file if this variable is set (to the desired shell command).
7537 This can be used to, e.g., store
7541 .Dl set netrc-pipe='gpg -qd ~/.netrc.pgp'
7545 If this variable has the value
7547 newly created local folders will be in Maildir format.
7551 Checks for new mail in the current folder each time the prompt is shown.
7552 A Maildir folder must be re-scanned to determine if new mail has arrived.
7553 If this variable is set to the special value
7555 then a Maildir folder will not be rescanned completely, but only
7556 timestamp changes are detected.
7560 .It Va on-compose-done-shell , on-compose-done
7561 These hooks run once the normal compose mode is finished, but before the
7562 .Va on-compose-leave
7563 macro hook is called, the
7566 Both hooks will be executed in a subprocess, with their input and output
7567 connected to \*(UA such that they can act as if they would be an
7569 The difference in between them is that the former is a
7571 command, whereas the latter is a normal \*(UA macro, but which is
7572 restricted to a small set of commands (the
7576 will indicate the said capability), just enough for the purpose of
7577 controlling the real \*(UA instance sufficiently.
7579 are by default enabled (in the parent) for (the lifetime of) these
7580 hooks, causing covered setting to be forgotten after the message has
7583 During execution of these hook \*(UA will temporarily forget whether it
7584 has been started in interactive mode, (a restricted set of)
7585 .Sx "COMMAND ESCAPES"
7586 will always be available, and for guaranteed reproduceabilities sake
7588 will be set to its default.
7589 The compose mode command
7591 has been especially designed for scriptability (via these hooks).
7592 The first line the hook will read on its standard input is the protocol
7593 version of said command escape, currently
7595 backward incompatible protocol changes are to be expected in the
7596 future, and it is advisable to make use of the protocol version.
7597 \*(ID because most \*(UA commands do not take this new functionality
7598 into account but are ment for human interaction special care must be
7599 taken to avoid deadlocks because of unexpected control flow; i.e., that
7600 both involved processes wait for more input to happen at the same time,
7601 or one doesn't expect more input but the other is stuck waiting for
7602 consumation of its output.
7603 .Bd -literal -offset indent
7604 wysh set on-compose-done-shell=$'\e
7606 printf "hello $version! Headers: ";\e
7607 echo \e'~^header list\e';\e
7608 read status result;\e
7609 echo "status=$status result=$result";\e
7612 set on-compose-done=ocdm
7615 echo version is $ver, escape=$escape
7616 if $features !@ +regex
7617 echoerr 'Need regular-expression support, aborting send'
7620 echo '~^header list'
7623 echoerr 'Failed to read header list, bailing out'
7627 echo '~^header insert cc Diet is your <mirr.or>'
7630 echoerr 'Failed to insert Cc: header, bailing out'
7639 .It Va on-compose-enter , on-compose-leave
7640 Macro hooks which will be executed before compose mode is entered, and
7641 after composing has been finished (but before the
7643 is injected, etc.), respectively.
7645 are by default enabled for these hooks, causing any setting to be
7646 forgotten after the message has been sent.
7647 The following variables will be set temporarily during execution of the
7650 .Bl -tag -compact -width ".It Va compose_subject"
7653 .It Va compose-sender
7655 .It Va compose-to , compose-cc , compose-bcc
7656 The list of receiver addresses as a space-separated list.
7657 .It Va compose-subject
7663 \*(BO Causes the filename given in the
7666 and the sender-based filenames for the
7670 commands to be interpreted relative to the directory given in the
7672 variable rather than to the current directory,
7673 unless it is set to an absolute pathname.
7677 \*(BO If set, each message feed through the command given for
7679 is followed by a formfeed character
7683 .It Va password-USER@HOST , password-HOST , password
7684 \*(IN Variable chain that sets a password, which is used in case none has
7685 been given in the protocol and account-specific URL;
7686 as a last resort \*(UA will ask for a password on the user's terminal if
7687 the authentication method requires a password.
7688 Specifying passwords in a startup file is generally a security risk;
7689 the file should be readable by the invoking user only.
7691 .It Va password-USER@HOST
7692 \*(OU (see the chain above for \*(IN)
7693 Set the password for
7697 If no such variable is defined for a host,
7698 the user will be asked for a password on standard input.
7699 Specifying passwords in a startup file is generally a security risk;
7700 the file should be readable by the invoking user only.
7704 \*(BO Send messages to the
7706 command without performing MIME and character set conversions.
7710 .It Va pipe-TYPE/SUBTYPE
7711 When a MIME message part of type
7713 (case-insensitive) is displayed or quoted,
7714 its text is filtered through the value of this variable interpreted as
7718 forces interpretation of the message part as plain text, e.g.,
7719 .Ql set pipe-application/xml=@
7720 will henceforth display XML
7722 (The same could also be achieved by adding a MIME type marker with the
7725 And \*(OPally MIME type handlers may be defined via
7726 .Sx "The Mailcap files"
7727 \(em corresponding flag strings are shown in parenthesis below.)
7732 can in fact be used to adjust usage and behaviour of a following shell
7733 command specification by appending trigger characters to it, e.g., the
7734 following hypothetical command specification could be used:
7735 .Bd -literal -offset indent
7736 set pipe-X/Y='@*!++=@vim ${NAIL_FILENAME_TEMPORARY}'
7740 .Bl -tag -compact -width ".It Ql __"
7742 Simply by using the special
7744 prefix the MIME type (shell command) handler will only be invoked to
7745 display or convert the MIME part if the message is addressed directly
7746 and alone by itself.
7747 Use this trigger to disable this and always invoke the handler
7748 .Pf ( Cd x-mailx-always ) .
7751 If set the handler will not be invoked when a message is to be quoted,
7752 but only when it will be displayed
7753 .Pf ( Cd x-mailx-noquote ) .
7756 The command will be run asynchronously, i.e., without blocking \*(UA,
7757 which may be a handy way to display a, e.g., PDF file while also
7758 continuing to read the mail message
7759 .Pf ( Cd x-mailx-async ) .
7760 Asynchronous execution implies
7764 The command must be run on an interactive terminal, \*(UA will
7765 temporarily release the terminal to it
7766 .Pf ( Cd needsterminal ) .
7767 This flag is mutual exclusive with
7769 will only be used in interactive mode and implies
7773 Request creation of a zero-sized temporary file, the absolute pathname
7774 of which will be made accessible via the environment variable
7775 .Ev NAIL_FILENAME_TEMPORARY
7776 .Pf ( Cd x-mailx-tmpfile ) .
7777 If this trigger is given twice then the file will be unlinked
7778 automatically by \*(UA when the command loop is entered again at latest
7779 .Pf ( Cd x-mailx-tmpfile-unlink ) .
7780 (Do not use this for asynchronous handlers.)
7783 Normally the MIME part content is passed to the handler via standard
7784 input; if this flag is set then the data will instead be written into
7785 .Ev NAIL_FILENAME_TEMPORARY
7786 .Pf ( Cd x-mailx-tmpfile-fill ) ,
7787 the creation of which is implied; note however that in order to cause
7788 deletion of the temporary file you still have to use two plus signs
7793 To avoid ambiguities with normal shell command content you can use
7794 another at-sign to forcefully terminate interpretation of remaining
7796 (Any character not in this list will have the same effect.)
7800 Some information about the MIME part to be displayed is embedded into
7801 the environment of the shell command:
7804 .Bl -tag -compact -width ".It Ev _AIL__ILENAME__ENERATED"
7807 The MIME content-type of the part, if known, the empty string otherwise.
7810 .It Ev NAIL_CONTENT_EVIDENCE
7812 .Va mime-counter-evidence
7813 includes the carry-around-bit (2), then this will be set to the detected
7814 MIME content-type; not only then identical to
7815 .Ev \&\&NAIL_CONTENT
7819 .It Ev NAIL_FILENAME
7820 The filename, if any is set, the empty string otherwise.
7823 .It Ev NAIL_FILENAME_GENERATED
7827 .It Ev NAIL_FILENAME_TEMPORARY
7828 If temporary file creation has been requested through the command prefix
7829 this variable will be set and contain the absolute pathname of the
7834 The temporary directory that \*(UA uses.
7835 Usually identical to
7837 but guaranteed to be set and usable by child processes;
7838 to ensure the latter condition for
7840 also, it will be set.
7845 .It Va pipe-EXTENSION
7846 This is identical to
7847 .Va pipe-TYPE/SUBTYPE
7850 (normalized to lowercase using character mappings of the ASCII charset)
7851 names a file extension, e.g.,
7853 Handlers registered using this method take precedence.
7856 .It Va pop3-auth-USER@HOST , pop3-auth-HOST , pop3-auth
7857 \*(OP\*(IN Variable chain that sets the POP3 authentication method.
7858 The only possible value as of now is
7860 which is thus the default.
7863 .Mx Va pop3-bulk-load
7864 .It Va pop3-bulk-load-USER@HOST , pop3-bulk-load-HOST , pop3-bulk-load
7865 \*(BO\*(OP When accessing a POP3 server \*(UA loads the headers of
7866 the messages, and only requests the message bodies on user request.
7867 For the POP3 protocol this means that the message headers will be
7869 If this variable is set then \*(UA will download only complete messages
7870 from the given POP3 server(s) instead.
7872 .Mx Va pop3-keepalive
7873 .It Va pop3-keepalive-USER@HOST , pop3-keepalive-HOST , pop3-keepalive
7874 \*(OP POP3 servers close the connection after a period of inactivity;
7875 the standard requires this to be at least 10 minutes,
7876 but practical experience may vary.
7877 Setting this variable to a numeric value greater than
7881 command to be sent each value seconds if no other operation is performed.
7884 .It Va pop3-no-apop-USER@HOST , pop3-no-apop-HOST , pop3-no-apop
7885 \*(BO\*(OP Unless this variable is set the
7887 authentication method will be used when connecting to a POP3 server that
7891 is that the password is not sent in clear text over the wire and that
7892 only a single packet is sent for the user/password tuple.
7894 .Va pop3-no-apop-HOST
7897 .Mx Va pop3-use-starttls
7898 .It Va pop3-use-starttls-USER@HOST , pop3-use-starttls-HOST , pop3-use-starttls
7899 \*(BO\*(OP Causes \*(UA to issue a
7901 command to make an unencrypted POP3 session SSL/TLS encrypted.
7902 This functionality is not supported by all servers,
7903 and is not used if the session is already encrypted by the POP3S method.
7905 .Va pop3-use-starttls-HOST
7910 \*(BO This flag enables POSIX mode, which changes behaviour of \*(UA
7911 where that deviates from standardized behaviour.
7912 It will be set implicitly before the
7913 .Sx "Resource files"
7914 are loaded if the environment variable
7916 is set, and adjusting any of those two will be reflected by the other
7920 .It Va print-alternatives
7921 \*(BO When a MIME message part of type
7922 .Ql multipart/alternative
7923 is displayed and it contains a subpart of type
7925 other parts are normally discarded.
7926 Setting this variable causes all subparts to be displayed,
7927 just as if the surrounding part was of type
7928 .Ql multipart/mixed .
7932 The string used as a prompt in interactive mode.
7933 Whenever the variable is evaluated the value is shell-expanded using
7934 dollar-single-quote expansion mode (see
7936 and it is an error if the prompt expands to more than a single token.
7937 This (post-assignment, i.e., second) expansion can be used to embed
7938 status information, for example
7942 .Va -mailbox-display .
7943 In order to embed characters which should not be counted when
7944 calculating the visual width of the resulting string, enclose the
7945 characters of interest in a pair of reverse solidus escaped brackets:
7947 Prompting may be prevented by setting this to the null string
7949 .Ql set noprompt ) .
7953 This string is used for secondary prompts, but is otherwise identical to
7960 \*(BO Suppresses the printing of the version when first invoked.
7964 If set, \*(UA starts a replying message with the original message
7965 prefixed by the value of the variable
7967 Normally, a heading consisting of
7968 .Dq Fromheaderfield wrote:
7969 is put before the quotation.
7974 variable, this heading is omitted.
7977 is assigned, only the headers selected by the
7980 selection are put above the message body,
7983 acts like an automatic
7985 .Sx "COMMAND ESCAPES"
7989 is assigned, all headers are put above the message body and all MIME
7990 parts are included, making
7992 act like an automatic
7995 .Va quote-as-attachment .
7998 .It Va quote-as-attachment
7999 \*(BO Add the original message in its entirety as a
8001 MIME attachment when replying to a message.
8002 Note this works regardless of the setting of
8007 \*(OP Can be set in addition to
8009 Setting this turns on a more fancy quotation algorithm in that leading
8010 quotation characters are compressed and overlong lines are folded.
8012 can be set to either one or two (space separated) numeric values,
8013 which are interpreted as the maximum (goal) and the minimum line length,
8014 respectively, in a spirit rather equal to the
8016 program, but line-, not paragraph-based.
8017 If not set explicitly the minimum will reflect the goal algorithmically.
8018 The goal cannot be smaller than the length of
8020 plus some additional pad.
8021 Necessary adjustments take place silently.
8024 .It Va r-option-implicit
8025 \*(BO Setting this option evaluates the contents of
8027 (or, if that contains multiple addresses,
8029 and passes the results onto the used (file-based) MTA as described for the
8031 option (empty argument case).
8034 .It Va recipients-in-cc
8035 \*(BO On group replies, specify only the sender of the original mail in
8037 and mention the other recipients in the secondary
8039 By default all recipients of the original mail will be addressed via
8044 If defined, gives the pathname of the folder used to record all outgoing
8046 If not defined, then outgoing mail is not saved.
8047 When saving to this folder fails the message is not sent,
8048 but instead saved to
8052 .It Va record-resent
8053 \*(BO If both this variable and the
8060 commands save messages to the
8062 folder as it is normally only done for newly composed messages.
8065 .It Va reply-in-same-charset
8066 \*(BO If this variable is set \*(UA first tries to use the same
8067 character set of the original message for replies.
8068 If this fails, the mechanism described in
8069 .Sx "Character sets"
8070 is evaluated as usual.
8073 .It Va reply_strings
8074 Can be set to a comma-separated list of (case-insensitive according to
8075 ASCII rules) strings which shall be recognized in addition to the
8078 reply message indicators \(en builtin are
8080 which is mandated by RFC 5322, as well as the german
8085 A list of addresses to put into the
8087 field of the message header.
8088 Members of this list are handled as if they were in the
8093 .It Va reply-to-honour
8096 header is honoured when replying to a message via
8100 This is a quadoption; if set without a value it defaults to
8104 .It Va rfc822-body-from_
8105 \*(BO This variable can be used to force displaying a so-called
8107 line for messages that are embedded into an envelope mail via the
8109 MIME mechanism, for more visual convenience.
8113 \*(BO Enable saving of (partial) messages in
8115 upon interrupt or delivery error.
8119 The number of lines that represents a
8128 line display and scrolling via
8130 If this variable is not set \*(UA falls back to a calculation based upon
8131 the detected terminal window size and the baud rate: the faster the
8132 terminal, the more will be shown.
8133 Overall screen dimensions and pager usage is influenced by the
8134 environment variables
8142 .It Va searchheaders
8143 \*(BO Expand message-list specifiers in the form
8145 to all messages containing the substring
8149 The string search is case insensitive.
8153 \*(OP A comma-separated list of character set names that can be used in
8154 outgoing internet mail.
8155 The value of the variable
8157 is automatically appended to this list of character-sets.
8158 If no character set conversion capabilities are compiled into \*(UA then
8159 the only supported charset is
8162 .Va sendcharsets-else-ttycharset
8163 and refer to the section
8164 .Sx "Character sets"
8165 for the complete picture of character set conversion in \*(UA.
8168 .It Va sendcharsets-else-ttycharset
8169 \*(BO\*(OP If this variable is set, but
8171 is not, then \*(UA acts as if
8173 had been set to the value of the variable
8175 In effect this combination passes through the message data in the
8176 character set of the current locale (given that
8178 has not been set manually), i.e., without converting it to the
8180 fallback character set.
8181 Thus, mail message text will be in ISO-8859-1 encoding when send from
8182 within a ISO-8859-1 locale, and in UTF-8 encoding when send from within
8184 If no character set conversion capabilities are available in \*(UA then
8185 the only supported character set is
8190 An address that is put into the
8192 field of outgoing messages, quoting RFC 5322: the mailbox of the agent
8193 responsible for the actual transmission of the message.
8194 This field should normally not be used unless the
8196 field contains more than one address, on which case it is required.
8199 address is handled as if it were in the
8203 .Va r-option-implicit .
8207 \*(OB Predecessor of
8211 .It Va sendmail-arguments
8212 \*(OB Predecessor of
8216 .It Va sendmail-no-default-arguments
8217 \*(OB\*(BO Predecessor of
8218 .Va mta-no-default-arguments .
8221 .It Va sendmail-progname
8222 \*(OB Predecessor of
8227 \*(BO When sending a message wait until the
8229 (including the builtin SMTP one) exits before accepting further commands.
8231 with this variable set errors reported by the MTA will be recognizable!
8232 If the MTA returns a non-zero exit status,
8233 the exit status of \*(UA will also be non-zero.
8237 \*(BO This setting causes \*(UA to start at the last message
8238 instead of the first one when opening a mail folder.
8242 \*(BO Causes \*(UA to use the sender's real name instead of the plain
8243 address in the header field summary and in message specifications.
8247 \*(BO Causes the recipient of the message to be shown in the header
8248 summary if the message was sent by the user.
8252 The string to expand
8255 .Sx "COMMAND ESCAPES" ) .
8259 The string to expand
8262 .Sx "COMMAND ESCAPES" ) .
8266 Must correspond to the name of a readable file if set.
8267 The file's content is then appended to each singlepart message
8268 and to the first part of each multipart message.
8269 Be warned that there is no possibility to edit the signature for an
8273 .It Va skipemptybody
8274 \*(BO If an outgoing message does not contain any text in its first or
8275 only message part, do not send it but discard it silently (see also the
8281 \*(OP Specifies a directory with CA certificates in PEM (Privacy
8282 Enhanced Mail) format for verification of S/MIME signed messages.
8285 .It Va smime-ca-file
8286 \*(OP Specifies a file with CA certificates in PEM format for
8287 verification of S/MIME signed messages.
8290 .It Va smime-cipher-USER@HOST , smime-cipher
8291 \*(OP Specifies the cipher to use when generating S/MIME encrypted
8292 messages (for the specified account).
8293 RFC 5751 mandates a default of
8296 Possible values are (case-insensitive and) in decreasing cipher strength:
8304 (DES EDE3 CBC, 168 bits; default if
8306 is not available) and
8310 The actually available cipher algorithms depend on the cryptographic
8311 library that \*(UA uses.
8312 \*(OP Support for more cipher algorithms may be available through
8313 dynamic loading via, e.g.,
8314 .Xr EVP_get_cipherbyname 3
8315 (OpenSSL) if \*(UA has been compiled to support this.
8318 .It Va smime-crl-dir
8319 \*(OP Specifies a directory that contains files with CRLs in PEM format
8320 to use when verifying S/MIME messages.
8323 .It Va smime-crl-file
8324 \*(OP Specifies a file that contains a CRL in PEM format to use when
8325 verifying S/MIME messages.
8328 .It Va smime-encrypt-USER@HOST
8329 \*(OP If this variable is set, messages send to the given receiver are
8330 encrypted before sending.
8331 The value of the variable must be set to the name of a file that
8332 contains a certificate in PEM format.
8334 If a message is sent to multiple recipients,
8335 each of them for whom a corresponding variable is set will receive an
8336 individually encrypted message;
8337 other recipients will continue to receive the message in plain text
8339 .Va smime-force-encryption
8341 It is recommended to sign encrypted messages, i.e., to also set the
8346 .It Va smime-force-encryption
8347 \*(BO\*(OP Causes \*(UA to refuse sending unencrypted messages.
8350 .It Va smime-no-default-ca
8351 \*(BO\*(OP Do not load default CA locations when verifying S/MIME
8356 \*(BO\*(OP S/MIME sign outgoing messages with the user's private key
8357 and include the user's certificate as a MIME attachment.
8358 Signing a message enables a recipient to verify that the sender used
8359 a valid certificate,
8360 that the email addresses in the certificate match those in the message
8361 header and that the message content has not been altered.
8362 It does not change the message text,
8363 and people will be able to read the message as usual.
8365 .Va smime-sign-cert , smime-sign-include-certs
8367 .Va smime-sign-message-digest .
8369 .Mx Va smime-sign-cert
8370 .It Va smime-sign-cert-USER@HOST , smime-sign-cert
8371 \*(OP Points to a file in PEM format.
8372 For the purpose of signing and decryption this file needs to contain the
8373 user's private key as well as his certificate.
8377 is always derived from the value of
8379 (or, if that contains multiple addresses,
8381 For the purpose of encryption the recipient's public encryption key
8382 (certificate) is expected; the command
8384 can be used to save certificates of signed messages (the section
8385 .Sx "Signed and encrypted messages with S/MIME"
8386 gives some details).
8387 This mode of operation is usually driven by the specialized form.
8389 When decrypting messages the account is derived from the recipient
8394 of the message, which are searched for addresses for which such
8396 \*(UA always uses the first address that matches,
8397 so if the same message is sent to more than one of the user's addresses
8398 using different encryption keys, decryption might fail.
8400 .Mx Va smime-sign-include-certs
8401 .It Va smime-sign-include-certs-USER@HOST , smime-sign-include-certs
8402 \*(OP If used, this is supposed to a consist of a comma-separated list
8403 of files, each of which containing a single certificate in PEM format to
8404 be included in the S/MIME message in addition to the
8407 This is most useful for long certificate chains if it is desired to aid
8408 the receiving parties verification process.
8409 Note that top level certificates may also be included in the chain but
8410 do not play a role for verification.
8412 .Va smime-sign-cert .
8413 Remember that for this
8415 refers to the variable
8417 (or, if that contains multiple addresses,
8420 .Mx Va smime-sign-message-digest
8421 .It Va smime-sign-message-digest-USER@HOST , smime-sign-message-digest
8422 \*(OP Specifies the message digest to use when signing S/MIME messages.
8423 RFC 5751 mandates a default of
8425 Possible values are (case-insensitive and) in decreasing cipher strength:
8433 The actually available message digest algorithms depend on the
8434 cryptographic library that \*(UA uses.
8435 \*(OP Support for more message digest algorithms may be available
8436 through dynamic loading via, e.g.,
8437 .Xr EVP_get_digestbyname 3
8438 (OpenSSL) if \*(UA has been compiled to support this.
8439 Remember that for this
8441 refers to the variable
8443 (or, if that contains multiple addresses,
8448 \*(OB\*(OP To use the builtin SMTP transport, specify a SMTP URL in
8450 \*(ID For compatibility reasons a set
8452 is used in preference of
8456 .It Va smtp-auth-USER@HOST , smtp-auth-HOST , smtp-auth
8457 \*(OP Variable chain that controls the SMTP
8459 authentication method, possible values are
8465 as well as the \*(OPal methods
8471 method does not need any user credentials,
8473 requires a user name and all other methods require a user name and
8481 .Va smtp-auth-password
8483 .Va smtp-auth-user ) .
8488 .Va smtp-auth-USER@HOST :
8489 may override dependent on sender address in the variable
8492 .It Va smtp-auth-password
8493 \*(OP\*(OU Sets the global fallback password for SMTP authentication.
8494 If the authentication method requires a password, but neither
8495 .Va smtp-auth-password
8497 .Va smtp-auth-password-USER@HOST
8499 \*(UA will ask for a password on the user's terminal.
8501 .It Va smtp-auth-password-USER@HOST
8503 .Va smtp-auth-password
8504 for specific values of sender addresses, dependent upon the variable
8507 .It Va smtp-auth-user
8508 \*(OP\*(OU Sets the global fallback user name for SMTP authentication.
8509 If the authentication method requires a user name, but neither
8512 .Va smtp-auth-user-USER@HOST
8514 \*(UA will ask for a user name on the user's terminal.
8516 .It Va smtp-auth-user-USER@HOST
8519 for specific values of sender addresses, dependent upon the variable
8523 .It Va smtp-hostname
8524 \*(OP\*(IN Normally \*(UA uses the variable
8526 to derive the necessary
8528 information in order to issue a
8535 can be used to use the
8537 from the SMTP account
8544 from the content of this variable (or, if that is the empty string,
8546 or the local hostname as a last resort).
8547 This often allows using an address that is itself valid but hosted by
8548 a provider other than which (in
8550 is about to send the message.
8551 Setting this variable also influences the generated
8554 .Mx Va smtp-use-starttls
8555 .It Va smtp-use-starttls-USER@HOST , smtp-use-starttls-HOST , smtp-use-starttls
8556 \*(BO\*(OP Causes \*(UA to issue a
8558 command to make an SMTP
8560 session SSL/TLS encrypted, i.e., to enable transport layer security.
8564 .It Va spam-interface
8565 \*(OP In order to use any of the spam-related commands (like, e.g.,
8567 the desired spam interface must be defined by setting this variable.
8568 Please refer to the manual section
8570 for the complete picture of spam handling in \*(UA.
8571 All or none of the following interfaces may be available:
8573 .Bl -tag -width ".It Ql _ilte_"
8579 .Pf ( Lk http://spamassassin.apache.org SpamAssassin )
8581 Different to the generic filter interface \*(UA will automatically add
8582 the correct arguments for a given command and has the necessary
8583 knowledge to parse the program's output.
8586 will have been compiled into the \*(UA binary if
8591 Shall it be necessary to define a specific connection type (rather than
8592 using a configuration file for that), the variable
8594 can be used as in, e.g.,
8595 .Ql -d server.example.com -p 783 .
8596 It is also possible to specify a per-user configuration via
8598 Note that this interface does not inspect the
8600 flag of a message for the command
8604 generic spam filter support via freely configurable hooks.
8605 This interface is meant for programs like
8607 and requires according behaviour in respect to the hooks' exit
8608 status for at least the command
8611 meaning a message is spam,
8615 for unsure and any other return value indicating a hard error);
8616 since the hooks can include shell code snippets diverting behaviour
8617 can be intercepted as necessary.
8619 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
8622 .Va spamfilter-spam ;
8625 contains examples for some programs.
8626 The process environment of the hooks will have the variables
8627 .Ev NAIL_TMPDIR , TMPDIR
8629 .Ev NAIL_FILENAME_GENERATED
8631 Note that spam score support for
8633 is not supported unless the \*(OPtional regular expression support is
8635 .Va spamfilter-rate-scanscore
8642 \*(OP Messages that exceed this size will not be passed through to the
8644 .Va spam-interface .
8645 If unset or 0, the default of 420000 bytes is used.
8648 .It Va spamc-command
8649 \*(OP The path to the
8653 .Va spam-interface .
8654 Note that the path is not expanded, but used
8656 A fallback path will have been compiled into the \*(UA binary if the
8657 executable had been found during compilation.
8660 .It Va spamc-arguments
8661 \*(OP Even though \*(UA deals with most arguments for the
8664 automatically, it may at least sometimes be desirable to specify
8665 connection-related ones via this variable, e.g.,
8666 .Ql -d server.example.com -p 783 .
8670 \*(OP Specify a username for per-user configuration files for the
8672 .Va spam-interface .
8673 If this is set to the empty string then \*(UA will use the name of the
8682 .It Va spamfilter-ham , spamfilter-noham , \
8683 spamfilter-nospam , spamfilter-rate , spamfilter-spam
8684 \*(OP Command and argument hooks for the
8686 .Va spam-interface .
8689 contains examples for some programs.
8692 .It Va spamfilter-rate-scanscore
8693 \*(OP Because of the generic nature of the
8696 spam scores are not supported for it by default, but if the \*(OPtional
8697 regular expression support is available then setting this variable can
8698 be used to overcome this restriction.
8699 It is interpreted as follows: first a number (digits) is parsed that
8700 must be followed by a semicolon
8702 and an extended regular expression.
8703 Then the latter is used to parse the first output line of the
8705 hook, and, in case the evaluation is successful, the group that has been
8706 specified via the number is interpreted as a floating point scan score.
8710 \*(OP Specifies a directory with CA certificates in PEM (Pricacy
8711 Enhanced Mail) for verification of of SSL/TLS server certificates.
8713 .Xr SSL_CTX_load_verify_locations 3
8714 for more information.
8718 \*(OP Specifies a file with CA certificates in PEM format for
8719 verification of SSL/TLS server certificates.
8721 .Xr SSL_CTX_load_verify_locations 3
8722 for more information.
8725 .It Va ssl-cert-USER@HOST , ssl-cert-HOST , ssl-cert
8726 \*(OP Variable chain that sets the file name for a SSL/TLS client
8727 certificate required by some servers.
8728 This is a direct interface to the
8732 function of the OpenSSL library, if available.
8734 .Mx Va ssl-cipher-list
8735 .It Va ssl-cipher-list-USER@HOST , ssl-cipher-list-HOST , ssl-cipher-list
8736 \*(OP Specifies a list of ciphers for SSL/TLS connections.
8737 This is a direct interface to the
8741 function of the OpenSSL library, if available; see
8743 for more information.
8744 By default \*(UA does not set a list of ciphers, in effect using a
8746 specific cipher (protocol standards ship with a list of acceptable
8747 ciphers), possibly cramped to what the actually used SSL/TLS library
8748 supports \(en the manual section
8749 .Sx "An example configuration"
8750 also contains a SSL/TLS use case.
8753 .It Va ssl-config-file
8754 \*(OP If this variable is set \*(UA will call
8755 .Xr CONF_modules_load_file 3
8756 to allow OpenSSL to be configured according to the host system wide
8758 If a non-empty value is given then this will be used to specify the
8759 configuration file to be used instead of the global OpenSSL default;
8760 note that in this case it is an error if the file cannot be loaded.
8761 The application name will always be passed as
8766 \*(OP Specifies a file that contains a CRL in PEM format to use when
8767 verifying SSL/TLS server certificates.
8771 \*(OP Specifies a directory that contains files with CRLs in PEM format
8772 to use when verifying SSL/TLS server certificates.
8775 .It Va ssl-key-USER@HOST , ssl-key-HOST , ssl-key
8776 \*(OP Variable chain that sets the file name for the private key of
8777 a SSL/TLS client certificate.
8778 If unset, the name of the certificate file is used.
8779 The file is expected to be in PEM format.
8780 This is a direct interface to the
8784 function of the OpenSSL library, if available.
8787 .It Va ssl-method-USER@HOST , ssl-method-HOST , ssl-method
8788 \*(OB\*(OP Please use the newer and more flexible
8790 instead: if both values are set,
8792 will take precedence!
8793 Can be set to the following values, the actually used
8795 specification to which it is mapped is shown in parenthesis:
8797 .Pf ( Ql -ALL, TLSv1.2 ) ,
8799 .Pf ( Ql -ALL, TLSv1.1 ) ,
8801 .Pf ( Ql -ALL, TLSv1 )
8804 .Pf ( Ql -ALL, SSLv3 ) ;
8809 and thus includes the SSLv3 protocol.
8810 Note that SSLv2 is no longer supported at all.
8813 .It Va ssl-no-default-ca
8814 \*(BO\*(OP Do not load default CA locations to verify SSL/TLS server
8818 .It Va ssl-protocol-USER@HOST , ssl-protocol-HOST , ssl-protocol
8819 \*(OP Specify the used SSL/TLS protocol.
8820 This is a direct interface to the
8824 function of the OpenSSL library, if available;
8825 otherwise an \*(UA internal parser is used which understands the
8826 following subset of (case-insensitive) command strings:
8832 as well as the special value
8834 Multiple specifications may be given via a comma-separated list which
8835 ignores any whitespace.
8838 plus prefix will enable a protocol, a
8840 minus prefix will disable it, so that
8842 will enable only the TLSv1.2 protocol.
8844 It depends upon the used TLS/SSL library which protocols are actually
8845 supported and which protocols are used if
8847 is not set, but note that SSLv2 is no longer supported at all and
8849 Especially for older protocols explicitly securing
8851 may be worthwile, see
8852 .Sx "An example configuration" .
8856 \*(OP Gives the pathname to an entropy daemon socket, see
8858 Not all SSL/TLS libraries support this.
8861 .It Va ssl-rand-file
8862 \*(OP Gives the filename to a file with random entropy data, see
8863 .Xr RAND_load_file 3 .
8864 If this variable is not set, or set to the empty string, or if the
8865 filename expansion failed, then
8866 .Xr RAND_file_name 3
8867 will be used to create the filename if, and only if,
8869 documents that the SSL PRNG is not yet sufficiently seeded.
8870 If \*(UA successfully seeded the SSL PRNG then it will update the file
8871 .Pf ( Xr RAND_write_file 3 ) .
8872 This variable is only used if
8874 is not set (or not supported by the SSL/TLS library).
8877 .It Va ssl-verify-USER@HOST , ssl-verify-HOST , ssl-verify
8878 \*(OP Variable chain that sets the action to be performed if an error
8879 occurs during SSL/TLS server certificate validation.
8880 Valid (case-insensitive) values are
8882 (fail and close connection immediately),
8884 (ask whether to continue on standard input),
8886 (show a warning and continue),
8888 (do not perform validation).
8894 If only set without an assigned value, then this setting inhibits the
8899 header fields that include obvious references to \*(UA.
8900 There are two pitfalls associated with this:
8901 First, the message id of outgoing messages is not known anymore.
8902 Second, an expert may still use the remaining information in the header
8903 to track down the originating mail user agent.
8908 suppression does not occur.
8913 (\*(OP) This specifies a comma-separated list of
8918 .Sx "On terminal control and line editor" ,
8919 escape commas with reverse solidus) to be used to overwrite or define
8921 Note that this variable will only be queried once at program startup and
8922 can thus only be specified in resource files or on the command line.
8925 String capabilities form
8927 pairs and are expected unless noted otherwise.
8928 Numerics have to be notated as
8930 where the number is expected in normal decimal notation.
8931 Finally, booleans do not have any value but indicate a true or false
8932 state simply by being defined or not; this indeed means that \*(UA
8933 does not support undefining an existing boolean.
8934 String capability values will undergo some expansions before use:
8935 for one notations like
8938 .Ql control-LETTER ,
8939 and for clarification purposes
8941 can be used to specify
8943 (the control notation
8945 could lead to misreadings when a left bracket follows, which it does for
8946 the standard CSI sequence);
8947 finally three letter octal sequences, as in
8950 To specify that a terminal supports 256-colours, and to define sequences
8951 that home the cursor and produce an audible bell, one might write:
8953 .Bd -literal -offset indent
8954 set termcap='Co#256,home=\eE[H,bel=^G'
8958 The following terminal capabilities are or may be meaningful for the
8959 operation of the builtin line editor or \*(UA in general:
8962 .Bl -tag -compact -width yay
8964 .It Cd colors Ns \0or Cd Co
8966 numeric capability specifying the maximum number of colours.
8967 Note that \*(UA does not actually care about the terminal beside that,
8968 but always emits ANSI / ISO 6429 escape sequences.
8971 .It Cd rmcup Ns \0or Cd te Ns \0/ Cd smcup Ns \0or Cd ti
8975 respectively: exit and enter the alternative screen
8977 effectively turning \*(UA into a fullscreen application.
8978 To disable that, set (at least) one to the empty string.
8980 .It Cd smkx Ns \0or Cd ks Ns \0/ Cd rmkx Ns \0or Cd ke
8984 respectively: enable and disable the keypad.
8985 This is always enabled if available, because it seems even keyboards
8986 without keypads generate other key codes for, e.g., cursor keys in that
8987 case, and only if enabled we see the codes that we are interested in.
8989 .It Cd ed Ns \0or Cd cd
8993 .It Cd clear Ns \0or Cd cl
8995 clear the screen and home cursor.
8996 (Will be simulated via
9001 .It Cd home Ns \0or Cd ho
9006 .It Cd el Ns \0or Cd ce
9008 clear to the end of line.
9009 (Will be simulated via
9011 plus repetitions of space characters.)
9013 .It Cd hpa Ns \0or Cd ch
9014 .Cd column_address :
9015 move the cursor (to the given column parameter) in the current row.
9016 (Will be simulated via
9022 .Cd carriage_return :
9023 move to the first column in the current row.
9024 The default builtin fallback is
9027 .It Cd cub1 Ns \0or Cd le
9029 move the cursor left one space (non-destructively).
9030 The default builtin fallback is
9033 .It Cd cuf1 Ns \0or Cd nd
9035 move the cursor right one space (non-destructively).
9036 The default builtin fallback is
9038 which is used by most terminals.
9046 Many more capabilities which describe key-sequences are documented for
9050 .It Va termcap-disable
9051 \*(OP Disable any interaction with a terminal control library.
9052 If set only some generic fallback builtins and possibly the content of
9054 describe the terminal to \*(UA.
9056 that this variable will only be queried once at program startup and can
9057 thus only be specified in resource files or on the command line.
9061 If defined, gives the number of lines of a message to be displayed
9064 if unset, the first five lines are printed, if set to 0 the variable
9067 If the value is negative then its absolute value will be used for right
9070 height; (shifting bitwise is like dividing algorithmically, but since
9071 it takes away bits the value decreases pretty fast).
9075 \*(BO If set then the
9077 command series will strip adjacent empty lines and quotations.
9081 The character set of the terminal \*(UA operates on,
9082 and the one and only supported character set that \*(UA can use if no
9083 character set conversion capabilities have been compiled into it,
9084 in which case it defaults to ISO-8859-1 unless it can deduce a value
9088 Refer to the section
9089 .Sx "Character sets"
9090 for the complete picture about character sets.
9093 .It Va typescript-mode
9094 \*(BO A special multiplex variable that disables all variables and
9095 settings which result in behaviour that interferes with running \*(UA in
9098 .Va colour-disable ,
9099 .Va line-editor-disable
9100 and (before startup completed only)
9101 .Va termcap-disable .
9102 Unsetting it does not restore the former state of the covered settings.
9106 For a safety-by-default policy \*(UA sets its process
9110 but this variable can be used to override that:
9111 set it to an empty value to do not change the (current) setting,
9112 otherwise the process file mode creation mask is updated to the new value.
9113 Child processes inherit the process file mode creation mask.
9116 .It Va user-HOST , user
9117 \*(IN Variable chain that sets a global fallback user name, which is
9118 used in case none has been given in the protocol and account-specific
9120 This variable defaults to the name of the user who runs \*(UA.
9124 \*(BO Setting this enables upward compatibility with \*(UA
9125 version 15.0 in respect to which configuration options are available and
9126 how they are handled.
9127 This manual uses \*(IN and \*(OU to refer to the new and the old way of
9128 doing things, respectively.
9132 \*(BO This setting, also controllable via the command line option
9134 causes \*(UA to be more verbose, e.g., it will display obsoletion
9135 warnings and SSL/TLS certificate chains.
9136 Even though marked \*(BO this option may be set twice in order to
9137 increase the level of verbosity even more, in which case even details of
9138 the actual message delivery and protocol conversations are shown.
9141 is sufficient to disable verbosity as such.
9147 .It Va version , version-major , version-minor , version-update
9148 \*(RO \*(UA version information: the first variable contains a string
9149 containing the complete version identification, the latter three contain
9150 only digits: the major, minor and update version numbers.
9151 The output of the command
9153 will include this information.
9156 .It Va writebackedited
9157 If this variable is set messages modified using the
9161 commands are written back to the current folder when it is quit;
9162 it is only honoured for writable folders in MBOX format, though.
9163 Note that the editor will be pointed to the raw message content in that
9164 case, i.e., neither MIME decoding nor decryption will have been
9165 performed, and proper RFC 4155
9167 quoting of newly added or edited content is also left as an excercise to
9171 .\" }}} (INTERNAL VARIABLES)
9174 .\" .Sh ENVIRONMENT {{{
9178 .Dq environment variable
9179 should be considered an indication that these variables are either
9180 standardized as vivid parts of process environments, or that they are
9181 commonly found in there.
9182 The process environment is inherited from the
9184 once \*(UA is started, and unless otherwise explicitly noted handling of
9185 the following variables transparently integrates into that of the
9186 .Sx "INTERNAL VARIABLES"
9187 from \*(UA's point of view.
9188 This means that, e.g., they can be managed via
9192 causing automatic program environment updates (to be inherited by
9193 newly created child processes).
9196 In order to transparently integrate other environment variables equally
9197 they need to be imported (linked) with the command
9199 This command can also be used to set and unset non-integrated
9200 environment variables from scratch, sufficient system support provided.
9201 The following example, applicable to a POSIX shell, sets the
9203 environment variable for \*(UA only, and beforehand exports the
9205 in order to affect any further processing in the running shell:
9207 .Bd -literal -offset indent
9208 $ EDITOR="vim -u ${HOME}/.vimrc"
9210 $ COLUMNS=80 \*(uA -R
9213 .Bl -tag -width ".It Ev BaNg"
9216 The user's preferred width in column positions for the terminal screen
9218 Queried and used once on program startup, actively managed for child
9219 processes and the MLE (see
9220 .Sx "On terminal control and line editor" )
9221 in interactive mode thereafter.
9225 The name of the (mailbox)
9227 to use for saving aborted messages if
9229 is set; this defaults to
9236 is set no output will be generated, otherwise the contents of the file
9241 Pathname of the text editor to use in the
9245 .Sx "COMMAND ESCAPES" .
9246 A default editor is used if this value is not defined.
9250 The user's home directory.
9251 This variable is only used when it resides in the process environment.
9258 .It Ev LANG , LC_ALL , LC_COLLATE , LC_CTYPE , LC_MESSAGES
9262 .Sx "Character sets" .
9266 The user's preferred number of lines on a page or the vertical screen
9267 or window size in lines.
9268 Queried and used once on program startup, actively managed for child
9269 processes in interactive mode thereafter.
9273 Pathname of the directory lister to use in the
9275 command when operating on local mailboxes.
9278 (path search through
9283 Upon startup \*(UA will actively ensure that this variable refers to the
9284 name of the user who runs \*(UA, in order to be able to pass a verified
9285 name to any newly created child process.
9289 Is used as the users
9291 .Sx "primary system mailbox"
9295 This is assumed to be an absolute pathname.
9299 \*(OP Overrides the default path search for
9300 .Sx "The Mailcap files" ,
9301 which is defined in the standard RFC 1524 as
9302 .Ql ~/.mailcap:\:/etc/mailcap:\:/usr/etc/mailcap:\:/usr/local/etc/mailcap .
9303 .\" TODO we should have a mailcaps-default virtual RDONLY option!
9304 (\*(UA makes it a configuration option, however.)
9305 Note this is not a search path, but a path search.
9309 Is used as a startup file instead of
9312 When \*(UA scripts are invoked on behalf of other users,
9313 either this variable should be set to
9317 command line option should be used in order to avoid side-effects from
9318 reading their configuration files.
9319 This variable is only used when it resides in the process environment.
9323 The name of the users mbox file.
9324 A logical subset of the special
9326 .Sx "filename transformations"
9327 that are documented for
9332 The fallback default is
9339 .Sx "secondary mailbox"
9340 is used as the file to save messages from the
9342 .Sx "primary system mailbox"
9343 that have been read.
9345 .Sx "Message states" .
9348 .It Ev NAIL_NO_SYSTEM_RC
9349 If this variable is set then reading of
9351 at startup is inhibited, i.e., the same effect is achieved as if \*(UA
9352 had been started up with the option
9354 This variable is only used when it resides in the process environment.
9358 \*(IN\*(OP This variable overrides the default location of the user's
9364 Pathname of the program to use for backing the command
9368 variable enforces usage of a pager for output.
9369 The default paginator is
9371 (path search through
9374 \*(UA inspects the contents of this variable: if its contains the string
9376 then a non-existing environment variable
9383 dependent on whether terminal control support is available and whether
9384 that supports full (alternative) screen mode or not (also see
9385 .Sx "On terminal control and line editor" ) .
9389 will optionally be set to
9396 A colon-separated list of directories that is searched by the shell when
9397 looking for commands, e.g.,
9398 .Ql /bin:/usr/bin:/usr/local/bin .
9401 .It Ev POSIXLY_CORRECT
9402 This variable is automatically looked for upon startup, see
9408 The shell to use for the commands
9413 .Sx "COMMAND ESCAPES"
9414 and when starting subprocesses.
9415 A default shell is used if this environment variable is not defined.
9418 .It Ev SOURCE_DATE_EPOCH
9419 If set, this specifies a time in seconds since the Unix epoch
9420 (1970-01-01) to be used in place of the current time.
9421 This is for the sake of reproduceability of tests, to be used during
9422 development or by software packagers.
9426 \*(OP The terminal type for which output is to be prepared.
9427 For extended colour and font control please refer to
9428 .Sx "Coloured display" ,
9429 and for terminal management in general to
9430 .Sx "On terminal control and line editor" .
9434 Used as directory for temporary files instead of
9437 This variable is only used when it resides in the process environment.
9443 (see there), but this variable is not standardized, should therefore not
9444 be used, and is only corrected if already set.
9448 Pathname of the text editor to use in the
9452 .Sx "COMMAND ESCAPES" .
9460 .Bl -tag -width ".It Pa BaNg"
9462 File giving initial commands.
9465 System wide initialization file.
9469 \*(OP Personal MIME type handler definition file, see
9470 .Sx "The Mailcap files" .
9471 (RFC 1524 location, the actual path is a configuration option.)
9475 \*(OP System wide MIME type handler definition file, see
9476 .Sx "The Mailcap files" .
9477 (RFC 1524 location, the actual path is a configuration option.)
9480 .It Pa ~/.mime.types
9481 Personal MIME types, see
9482 .Sx "The mime.types files" .
9485 .It Pa /etc/mime.types
9486 System wide MIME types, see
9487 .Sx "The mime.types files" .
9491 \*(IN\*(OP The default location of the users
9493 file \(en the section
9494 .Sx "The .netrc file"
9495 documents the file format.
9498 .\" .Ss "The mime.types files" {{{
9499 .Ss "The mime.types files"
9501 When sending messages \*(UA tries to determine the content type of all
9503 When displaying message content or attachments \*(UA uses the content
9504 type to decide whether it can directly display data or whether it needs
9505 to deal with content handlers.
9506 It learns about M(ultipurpose) I(nternet) M(ail) E(xtensions) types and
9507 how to treat them by reading
9509 files, the loading of which can be controlled by setting the variable
9510 .Va mimetypes-load-control .
9513 can also be used to deal with MIME types.)
9515 files have the following syntax:
9518 .Dl type/subtype extension [extension ...]
9523 are strings describing the file contents, and one or multiple
9525 s, separated by whitespace, name the part of a filename starting after
9526 the last dot (of interest).
9527 Comments may be introduced anywhere on a line with a number sign
9529 causing the remaining line to be discarded.
9531 \*(UA also supports an extended, non-portable syntax in specially
9532 crafted files, which can be loaded via the alternative value syntax of
9533 .Va mimetypes-load-control
9534 and prepends an optional
9538 .Dl [type-marker ]type/subtype extension [extension ...]
9541 The following type markers are supported:
9544 .Bl -tag -compact -width ".It Ar _n_u"
9546 Treat message parts with this content as plain text.
9551 Treat message parts with this content as HTML tagsoup.
9552 If the \*(OPal HTML-tagsoup-to-text converter is not available treat
9553 the content as plain text instead.
9557 but instead of falling back to plain text require an explicit content
9558 handler to be defined.
9563 for sending messages:
9565 .Va mime-allow-text-controls ,
9566 .Va mimetypes-load-control .
9567 For reading etc. messages:
9568 .Sx "HTML mail and MIME attachments" ,
9569 .Sx "The Mailcap files" ,
9571 .Va mime-counter-evidence ,
9572 .Va mimetypes-load-control ,
9573 .Va pipe-TYPE/SUBTYPE ,
9574 .Va pipe-EXTENSION .
9577 .\" .Ss "The Mailcap files" {{{
9578 .Ss "The Mailcap files"
9581 .Dq User Agent Configuration Mechanism
9582 which \*(UA \*(OPally supports.
9583 It defines a file format to be used to inform mail user agent programs
9584 about the locally-installed facilities for handling various data
9585 formats, i.e., about commands and how they can be used to display, edit
9586 etc. MIME part contents, as well as a default path search that includes
9587 multiple possible locations of
9591 environment variable that can be used to overwrite that (repeating here
9592 that it is not a search path, but instead a path search specification).
9593 Any existing files will be loaded in sequence, appending any content to
9594 the list of MIME type handler directives.
9598 files consist of a set of newline separated entries.
9599 Comment lines start with a number sign
9601 (in the first column!) and are ignored.
9602 Empty lines are also ignored.
9603 All other lines form individual entries that must adhere to the syntax
9605 To extend a single entry (not comment) its line can be continued on
9606 follow lines if newline characters are
9608 by preceding them with the reverse solidus character
9610 The standard does not specify how leading whitespace of follow lines
9611 is to be treated, therefore \*(UA retains it.
9615 entries consist of a number of semicolon
9617 separated fields, and the reverse solidus
9619 character can be used to escape any following character including
9620 semicolon and itself.
9621 The first two fields are mandatory and must occur in the specified
9622 order, the remaining fields are optional and may appear in any order.
9623 Leading and trailing whitespace of content is ignored (removed).
9626 The first field defines the MIME
9628 the entry is about to handle (case-insensitively, and no reverse solidus
9629 escaping is possible in this field).
9630 If the subtype is specified as an asterisk
9632 the entry is meant to match all subtypes of the named type, e.g.,
9634 would match any audio type.
9635 The second field defines the shell command which shall be used to
9637 MIME parts of the given type; it is implicitly called the
9644 shell commands message (MIME part) data is passed via standard input
9645 unless the given shell command includes one or more instances of the
9648 in which case these instances will be replaced with a temporary filename
9649 and the data will have been stored in the file that is being pointed to.
9652 shell commands data is assumed to be generated on standard output unless
9653 the given command includes (one ore multiple)
9655 In any case any given
9657 format is replaced with a(n already) properly quoted filename.
9658 Note that when a command makes use of a temporary file via
9660 then \*(UA will remove it again, as if the
9661 .Cd x-mailx-tmpfile ,
9662 .Cd x-mailx-tmpfile-fill
9664 .Cd x-mailx-tmpfile-unlink
9665 flags had been set; see below for more.
9668 The optional fields either define a shell command or an attribute (flag)
9669 value, the latter being a single word and the former being a keyword
9670 naming the field followed by an equals sign
9672 succeeded by a shell command, and as usual for any
9674 content any whitespace surrounding the equals sign will be removed, too.
9675 Optional fields include the following:
9678 .Bl -tag -width ".It Cd BaNg"
9680 A program that can be used to compose a new body or body part in the
9687 field, but is to be used when the composing program needs to specify the
9689 header field to be applied to the composed data.
9693 A program that can be used to edit a body or body part in the given
9698 A program that can be used to print a message or body part in the given
9703 Specifies a program to be run to test some condition, e.g., the machine
9704 architecture, or the window system in use, to determine whether or not
9705 this mailcap entry applies.
9706 If the test fails, a subsequent mailcap entry should be sought; also see
9707 .Cd x-mailx-test-once .
9709 .It Cd needsterminal
9710 This flag field indicates that the given shell command must be run on
9711 an interactive terminal.
9712 \*(UA will temporarily release the terminal to the given command in
9713 interactive mode, in non-interactive mode this entry will be entirely
9714 ignored; this flag implies
9715 .Cd x-mailx-noquote .
9717 .It Cd copiousoutput
9718 A flag field which indicates that the output of the
9720 command will be an extended stream of textual output that can be
9721 (re)integrated into \*(UA's normal visual display.
9722 It is mutually exclusive with
9725 .Cd x-mailx-always .
9727 .It Cd textualnewlines
9728 A flag field which indicates that this type of data is line-oriented and
9731 all newlines should be converted to canonical form (CRLF) before
9732 encoding, and will be in that form after decoding.
9736 This field gives a file name format, in which
9738 will be replaced by a random string, the joined combination of which
9739 will be used as the filename denoted by
9740 .Ev NAIL_FILENAME_TEMPORARY .
9741 One could specify that a GIF file being passed to an image viewer should
9742 have a name ending in
9745 .Ql nametemplate=%s.gif .
9746 Note that \*(UA ignores the name template unless that solely specifies
9747 a filename suffix that consists of (ASCII) alphabetic and numeric
9748 characters, the underscore and dot only.
9751 Names a file, in X11 bitmap (xbm) format, which points to an appropriate
9752 icon to be used to visually denote the presence of this kind of data.
9753 This field is not used by \*(UA.
9756 A textual description that describes this type of data.
9758 .It Cd x-mailx-always
9759 Extension flag field that denotes that the given
9761 command shall be executed even if multiple messages will be displayed
9763 Normally messages which require external viewers that produce output
9764 which does not integrate into \*(UA's visual display (i.e., do not have
9766 set) have to be addressed directly and individually.
9767 (To avoid cases where, e.g., a thousand PDF viewer instances are spawned
9770 .It Cd x-mailx-even-if-not-interactive
9771 An extension flag test field \(em by default handlers without
9773 are entirely ignored in non-interactive mode, but if this flag is set
9774 then their use will be considered.
9775 It is an error if this flag is set for commands that use the flag
9778 .It Cd x-mailx-noquote
9779 An extension flag field that indicates that even a
9782 command shall not be used to generate message quotes
9783 (as it would be by default).
9785 .It Cd x-mailx-async
9786 Extension flag field that denotes that the given
9788 command shall be executed asynchronously, without blocking \*(UA.
9789 Cannot be used in conjunction with
9792 .It Cd x-mailx-test-once
9793 Extension flag which denotes whether the given
9795 command shall be evaluated once only and the (boolean) result be cached.
9796 This is handy if some global unchanging condition is to be queried, like
9797 .Dq running under the X Window System .
9799 .It Cd x-mailx-tmpfile
9800 Extension flag field that requests creation of a zero-sized temporary
9801 file, the name of which is to be placed in the environment variable
9802 .Ev NAIL_FILENAME_TEMPORARY .
9803 It is an error to use this flag with commands that include a
9807 .It Cd x-mailx-tmpfile-fill
9808 Normally the MIME part content is passed to the handler via standard
9809 input; if this flag is set then the data will instead be written into
9811 .Cd x-mailx-tmpfile .
9812 In order to cause deletion of the temporary file you will have to set
9813 .Cd x-mailx-tmpfile-unlink
9815 It is an error to use this flag with commands that include a
9819 .It Cd x-mailx-tmpfile-unlink
9820 Extension flag field that requests that the temporary file shall be
9821 deleted automatically when the command loop is entered again at latest.
9822 (Do not use this for asynchronous handlers.)
9823 It is an error to use this flag with commands that include a
9825 format, or without also setting
9828 .Cd x-mailx-tmpfile-fill .
9830 .It Cd x-mailx-tmpfile-keep
9833 implies the three tmpfile related flags above, but if you want, e.g.,
9835 and deal with the temporary file yourself, you can add in this flag to
9837 .Cd x-mailx-tmpfile-unlink .
9842 The standard includes the possibility to define any number of additional
9843 entry fields, prefixed by
9845 Flag fields apply to the entire
9847 entry \(em in some unusual cases, this may not be desirable, but
9848 differentiation can be accomplished via separate entries, taking
9849 advantage of the fact that subsequent entries are searched if an earlier
9850 one does not provide enough information.
9853 command needs to specify the
9857 command shall not, the following will help out the latter (with enabled
9861 level \*(UA will show information about handler evaluation):
9863 .Bd -literal -offset indent
9864 application/postscript; ps-to-terminal %s; needsterminal
9865 application/postscript; ps-to-terminal %s; compose=idraw %s
9869 In fields any occurrence of the format string
9871 will be replaced by the
9874 Named parameters from the
9876 field may be placed in the command execution line using
9878 followed by the parameter name and a closing
9881 The entire parameter should appear as a single command line argument,
9882 regardless of embedded spaces; thus:
9884 .Bd -literal -offset indent
9886 Content-type: multipart/mixed; boundary=42
9889 multipart/*; /usr/local/bin/showmulti \e
9890 %t %{boundary} ; composetyped = /usr/local/bin/makemulti
9892 # Executed shell command
9893 /usr/local/bin/showmulti multipart/mixed 42
9897 .\" TODO v15: Mailcap: %n,%F
9898 Note that \*(UA does not support handlers for multipart MIME parts as
9899 shown in this example (as of today).
9900 \*(UA does not support the additional formats
9904 An example file, also showing how to properly deal with the expansion of
9906 which includes any quotes that are necessary to make it a valid shell
9907 argument by itself and thus will cause undesired behaviour when placed
9908 in additional user-provided quotes:
9910 .Bd -literal -offset indent
9912 text/richtext; richtext %s; copiousoutput
9914 text/x-perl; perl -cWT %s
9918 trap "rm -f ${infile}" EXIT\e; \e
9919 trap "exit 75" INT QUIT TERM\e; \e
9921 x-mailx-async; x-mailx-tmpfile-keep
9923 application/*; echo "This is \e"%t\e" but \e
9924 is 50 \e% Greek to me" \e; < %s head -c 1024 | cat -vET; \e
9925 copiousoutput; x-mailx-noquote
9930 .Sx "HTML mail and MIME attachments" ,
9931 .Sx "The mime.types files" ,
9934 .Va mime-counter-evidence ,
9935 .Va pipe-TYPE/SUBTYPE ,
9936 .Va pipe-EXTENSION .
9939 .\" .Ss "The .netrc file" {{{
9940 .Ss "The .netrc file"
9944 file contains user credentials for machine accounts.
9945 The default location in the user's
9947 directory may be overridden by the
9949 environment variable.
9950 The file consists of space, tabulator or newline separated tokens.
9951 \*(UA implements a parser that supports a superset of the original BSD
9952 syntax, but users should nonetheless be aware of portability glitches
9953 of that file format, shall their
9955 be usable across multiple programs and platforms:
9958 .Bl -bullet -compact
9960 BSD does not support single, but only double quotation marks, e.g.,
9961 .Ql password="pass with spaces" .
9963 BSD (only?) supports escaping of single characters via a reverse solidus
9964 (e.g., a space can be escaped via
9966 in- as well as outside of a quoted string.
9968 BSD does not require a final quotation mark of the last user input token.
9970 The original BSD (Berknet) parser also supported a format which allowed
9971 tokens to be separated with commas \(en whereas at least Hewlett-Packard
9972 still seems to support this syntax, \*(UA does not!
9974 As a non-portable extension some widely-used programs support
9975 shell-style comments: if an input line starts, after any amount of
9976 whitespace, with a number sign
9978 then the rest of the line is ignored.
9980 Whereas other programs may require that the
9982 file is accessible by only the user if it contains a
9988 \*(UA will always require these strict permissions.
9992 Of the following list of supported tokens \*(UA only uses (and caches)
9997 At runtime the command
9999 can be used to control \*(UA's
10003 .Bl -tag -width ".It Cd BaNg"
10004 .It Cd machine Ar name
10005 The hostname of the entries' machine, lowercase-normalized by \*(UA
10007 Any further file content, until either end-of-file or the occurrence
10012 first-class token is bound (only related) to the machine
10015 As an extension that should not be the cause of any worries
10016 \*(UA supports a single wildcard prefix for
10018 .Bd -literal -offset indent
10019 machine *.example.com login USER password PASS
10020 machine pop3.example.com login USER password PASS
10021 machine smtp.example.com login USER password PASS
10027 .Ql pop3.example.com ,
10031 .Ql local.smtp.example.com .
10032 Note that in the example neither
10033 .Ql pop3.example.com
10035 .Ql smtp.example.com
10036 will be matched by the wildcard, since the exact matches take
10037 precedence (it is however faster to specify it the other way around).
10040 This is the same as
10042 except that it is a fallback entry that is used shall none of the
10043 specified machines match; only one default token may be specified,
10044 and it must be the last first-class token.
10046 .It Cd login Ar name
10047 The user name on the remote machine.
10049 .It Cd password Ar string
10050 The user's password on the remote machine.
10052 .It Cd account Ar string
10053 Supply an additional account password.
10054 This is merely for FTP purposes.
10056 .It Cd macdef Ar name
10058 A macro is defined with the specified
10060 it is formed from all lines beginning with the next line and continuing
10061 until a blank line is (consecutive newline characters are) encountered.
10064 entries cannot be utilized by multiple machines, too, but must be
10065 defined following the
10067 they are intended to be used with.)
10070 exists, it is automatically run as the last step of the login process.
10071 This is merely for FTP purposes.
10078 .\" .Sh EXAMPLES {{{
10081 .\" .Ss "An example configuration" {{{
10082 .Ss "An example configuration"
10084 .Bd -literal -offset indent
10085 # This example assumes v15.0 compatibility mode
10088 # Where are the up-to-date SSL certificates?
10089 #set ssl-ca-dir=/etc/ssl/certs
10090 set ssl-ca-file=/etc/ssl/certs/ca-certificates.crt
10092 # (Since we manage up-to-date ones explicitly, do not use any,
10093 # possibly outdated, default certificates shipped with OpenSSL)
10094 set ssl-no-default-ca
10096 # Do not use protocols older than TLS v1.2.
10097 # Change this only when the remote server does not support it:
10098 # maybe use ssl-protocol-HOST (or -USER@HOST) syntax to define
10099 # such explicit exceptions, then
10100 set ssl-protocol='-ALL,+TLSv1.2'
10102 # Explicitly define the list of ciphers, which may improve security,
10103 # especially with protocols older than TLS v1.2. See ciphers(1).
10104 # Including "@STRENGTH" will sort the final list by algorithm strength.
10105 # In reality it is possibly best to only use ssl-cipher-list-HOST
10106 # (or -USER@HOST), as necessary, again..
10107 set ssl-cipher-list=TLSv1.2:!aNULL:!eNULL:!MEDIUM:!LOW:!EXPORT:@STRENGTH
10108 # ALL:!aNULL:!MEDIUM:!LOW:!MD5:!RC4:!EXPORT:@STRENGTH
10110 # Request strict transport security checks!
10111 set ssl-verify=strict
10113 # Essential setting: select allowed character sets
10114 set sendcharsets=utf-8,iso-8859-1
10116 # A very kind option: when replying to a message, first try to
10117 # use the same encoding that the original poster used herself!
10118 set reply-in-same-charset
10120 # When replying to or forwarding a message the comment and name
10121 # parts of email addresses are removed unless this variable is set
10124 # When sending messages, wait until the Mail-Transfer-Agent finishs.
10125 # Only like this you will be able to see errors reported through the
10126 # exit status of the MTA (including the builtin SMTP one)!
10129 # Only use builtin MIME types, no mime.types(5) files
10130 set mimetypes-load-control
10132 # Default directory where we act in (relative to $HOME)
10134 # A leading "+" (often) means: under *folder*
10135 # *record* is used to save copies of sent messages
10136 set MBOX=+mbox.mbox record=+sent.mbox DEAD=+dead.txt
10138 # Make "file mymbox" and "file myrec" go to..
10139 shortcut mymbox %:+mbox.mbox myrec +sent.mbox
10141 # Not really optional, e.g., for S/MIME
10142 set from='Your Name <address@exam.ple>'
10144 # It may be necessary to set hostname and/or smtp-hostname
10145 # if the "SERVER" of mta and "domain" of from do not match.
10146 # The `urlencode' command can be used to encode USER and PASS
10147 set mta=(smtps?|submission)://[USER[:PASS]@]SERVER[:PORT] \e
10148 smtp-auth=login/plain... \e
10151 # Never refuse to start into interactive mode, and more
10153 colour-pager crt= \e
10154 followup-to followup-to-honour=ask-yes \e
10155 history-file=+.\*(uAhist history-size=-1 history-gabby \e
10156 mime-counter-evidence=0xE \e
10157 prompt='[\e${-account-name} \e${-mailbox-display}]? ' \e
10158 reply-to-honour=ask-yes \e
10161 # Only include the selected header fields when typing messages
10162 headerpick type retain add from_ date from to cc subject \e
10163 message-id mail-followup-to reply-to
10164 # ...when forwarding messages
10165 headerpick forward retain add subject date from to cc
10166 # ...when saving message, etc.
10167 #headerpick save ignore add ^Original-.*$ ^X-.*$
10169 # Some mailing lists
10170 mlist '@xyz-editor\e.xyz$' '@xyzf\e.xyz$'
10171 mlsubscribe '^xfans@xfans\e.xyz$'
10173 # A real life example of a very huge free mail provider
10175 set folder=~/spool/XooglX inbox=+syste.mbox sent=+sent
10176 set from='Your Name <address@examp.ple>'
10177 set mta=smtp://USER:PASS@smtp.gmXil.com smtp-use-starttls
10180 # Here is a pretty large one which does not allow sending mails
10181 # if there is a domain name mismatch on the SMTP protocol level,
10182 # which would bite us if the value of from does not match, e.g.,
10183 # for people who have a sXXXXeforge project and want to speak
10184 # with the mailing list under their project account (in from),
10185 # still sending the message through their normal mail provider
10187 set folder=~/spool/XandeX inbox=+syste.mbox sent=+sent
10188 set from='Your Name <address@exam.ple>'
10189 set mta=smtps://USER:PASS@smtp.yaXXex.ru:465 \e
10190 hostname=yaXXex.com smtp-hostname=
10193 # Create some new commands so that, e.g., `ls /tmp' will..
10194 wysh ghost lls '!ls ${LS_COLOR_FLAG} -aFlrS'
10195 wysh ghost llS '!ls ${LS_COLOR_FLAG} -aFlS'
10196 wysh ghost ls '!ls ${LS_COLOR_FLAG} -aFrS'
10197 wysh ghost lS '!ls ${LS_COLOR_FLAG} -aFS'
10198 wysh ghost lla '!ls ${LS_COLOR_FLAG} -aFlr'
10199 wysh ghost llA '!ls ${LS_COLOR_FLAG} -aFl'
10200 wysh ghost la '!ls ${LS_COLOR_FLAG} -aFr'
10201 wysh ghost lA '!ls ${LS_COLOR_FLAG} -aF'
10202 wysh ghost ll '!ls ${LS_COLOR_FLAG} -aFltr'
10203 wysh ghost lL '!ls ${LS_COLOR_FLAG} -aFlt'
10204 wysh ghost l '!ls ${LS_COLOR_FLAG} -aFtr'
10205 wysh ghost L '!ls ${LS_COLOR_FLAG} -aFt'
10207 # We do not support gpg(1) directly yet. But simple --clearsign'd
10208 # message parts can be dealt with as follows:
10210 wysh set pipe-text/plain=$'@*#++=@\e
10211 < "${NAIL_FILENAME_TEMPORARY}" awk \e
10212 -v TMPFILE="${NAIL_FILENAME_TEMPORARY}" \e'\e
10214 /^-----BEGIN PGP SIGNED MESSAGE-----/,/^$/{\e
10217 print "--- GPG --verify ---";\e
10218 system("gpg --verify " TMPFILE " 2>&1");\e
10219 print "--- GPG --verify ---";\e
10223 /^-----BEGIN PGP SIGNATURE-----/,\e
10224 /^-----END PGP SIGNATURE-----/{\e
10234 !printf 'Key IDs to gpg --recv-keys: ';\e
10236 gpg --recv-keys ${keyids};
10242 When storing passwords in
10244 appropriate permissions should be set on this file with
10245 .Ql $ chmod 0600 \*(ur .
10248 is available user credentials can be stored in the central
10250 file instead; e.g., here is a different version of the example account
10251 that sets up SMTP and POP3:
10253 .Bd -literal -offset indent
10255 set folder=~/spool/XandeX inbox=+syste.mbox sent=+sent
10256 set from='Your Name <address@exam.ple>'
10258 # Load an encrypted ~/.netrc by uncommenting the next line
10259 #set netrc-pipe='gpg -qd ~/.netrc.pgp'
10261 set mta=smtps://smtp.yXXXXx.ru:465 \e
10262 smtp-hostname= hostname=yXXXXx.com
10263 set pop3-keepalive=240 pop3-no-apop-pop.yXXXXx.ru
10264 ghost xp fi pop3s://pop.yXXXXx.ru
10273 .Bd -literal -offset indent
10274 machine *.yXXXXx.ru login USER password PASS
10278 This configuration should now work just fine:
10281 .Dl $ echo text | \*(uA -vv -AXandeX -s Subject user@exam.ple
10284 .\" .Ss "Signed and encrypted messages with S/MIME" {{{
10285 .Ss "Signed and encrypted messages with S/MIME"
10287 \*(OP S/MIME provides two central mechanisms:
10288 message signing and message encryption.
10289 A signed message contains some data in addition to the regular text.
10290 The data can be used to verify that the message was sent using a valid
10291 certificate, that the sender's address in the message header matches
10292 that in the certificate, and that the message text has not been altered.
10293 Signing a message does not change its regular text;
10294 it can be read regardless of whether the recipient's software is able to
10298 It is thus usually possible to sign all outgoing messages if so desired.
10299 Encryption, in contrast, makes the message text invisible for all people
10300 except those who have access to the secret decryption key.
10301 To encrypt a message, the specific recipient's public encryption key
10303 It is therefore not possible to send encrypted mail to people unless their
10304 key has been retrieved from either previous communication or public key
10306 A message should always be signed before it is encrypted.
10307 Otherwise, it is still possible that the encrypted message text is
10311 A central concept to S/MIME is that of the certification authority (CA).
10312 A CA is a trusted institution that issues certificates.
10313 For each of these certificates it can be verified that it really
10314 originates from the CA, provided that the CA's own certificate is
10316 A set of CA certificates is usually delivered with OpenSSL and installed
10318 If you trust the source of your OpenSSL software installation,
10319 this offers reasonable security for S/MIME on the Internet.
10321 .Va smime-no-default-ca
10322 to avoid using the default certificate and point
10326 to a trusted pool of certificates.
10327 In general, a certificate cannot be more secure than the method its CA
10328 certificate has been retrieved with.
10331 The first thing you need for participating in S/MIME message exchange is
10332 your personal certificate, including a private key.
10333 The certificate contains public information, in particular your name and
10334 your email address(es), and the public key that is used by others to
10335 encrypt messages for you,
10336 and to verify signed messages they supposedly received from you.
10337 The certificate is included in each signed message you send.
10338 The private key must be kept secret.
10339 It is used to decrypt messages that were previously encrypted with your
10340 public key, and to sign messages.
10343 For personal use it is recommended that you get a S/MIME certificate
10344 from one of the major CAs on the Internet using your WWW browser.
10345 Many CAs offer such certificates for free.
10347 .Lk https://www.CAcert.org
10348 which issues client and server certificates to members of their
10349 community for free; their root certificate
10350 .Pf ( Lk https://\:www.cacert.org/\:certs/\:root.crt )
10351 is often not in the default set of trusted CA root certificates, though,
10352 which means you will have to download their root certificate separately
10353 and ensure it is part of our S/MIME certificate validation chain by
10356 or as a vivid member of the
10357 .Va smime-ca-file .
10358 But let us take a step-by-step tour on how to setup S/MIME with
10359 a certificate from CAcert.org despite this situation!
10362 First of all you will have to become a member of the CAcert.org
10363 community, simply by registrating yourself via the web interface.
10364 Once you are, create and verify all email addresses you want to be able
10365 to create signed and encrypted messages for/with using the corresponding
10366 entries of the web interface.
10367 Now ready to create S/MIME certificates, so let us create a new
10368 .Dq client certificate ,
10369 ensure to include all email addresses that should be covered by the
10370 certificate in the following web form, and also to use your name as the
10374 Create a private key and a certificate request on your local computer
10375 (please see the manual pages of the used commands for more in-depth
10376 knowledge on what the used arguments etc. do):
10379 .Dl openssl req -nodes -newkey rsa:4096 -keyout key.pem -out creq.pem
10382 Afterwards copy-and-paste the content of
10384 into the certificate-request (CSR) field of the web form on the
10385 CAcert.org website (you may need to unfold some
10386 .Dq advanced options
10387 to see the corresponding text field).
10388 This last step will ensure that your private key (which never left your
10389 box) and the certificate belong together (through the public key that
10390 will find its way into the certificate via the certificate-request).
10391 You are now ready and can create your CAcert certified certificate.
10392 Download and store or copy-and-paste it as
10397 In order to use your new S/MIME setup you will have to create
10398 a combined private key/public key (certificate) file:
10401 .Dl cat key.pem pub.crt > ME@HERE.com.paired
10404 This is the file \*(UA will work with.
10405 If you have created your private key with a passphrase then \*(UA will
10406 ask you for it whenever a message is signed or decrypted.
10407 Set the following variables to henceforth use S/MIME (setting
10409 is of interest for verification only):
10411 .Bd -literal -offset indent
10412 set smime-ca-file=ALL-TRUSTED-ROOT-CERTS-HERE \e
10413 smime-sign-cert=ME@HERE.com.paired \e
10414 smime-sign-message-digest=SHA256 \e
10419 From each signed message you send, the recipient can fetch your
10420 certificate and use it to send encrypted mail back to you.
10421 Accordingly if somebody sends you a signed message, you can do the same,
10424 command to check the validity of the certificate.
10427 Variables of interest for S/MIME signing:
10429 .Va smime-ca-file ,
10430 .Va smime-crl-dir ,
10431 .Va smime-crl-file ,
10432 .Va smime-no-default-ca ,
10434 .Va smime-sign-cert ,
10435 .Va smime-sign-include-certs
10437 .Va smime-sign-message-digest .
10440 After it has been verified save the certificate via
10442 and tell \*(UA that it should use it for encryption for further
10443 communication with that somebody:
10445 .Bd -literal -offset indent
10447 set smime-encrypt-USER@HOST=FILENAME \e
10448 smime-cipher-USER@HOST=AES256
10452 Additional variables of interest for S/MIME en- and decryption:
10455 .Va smime-encrypt-USER@HOST .
10458 You should carefully consider if you prefer to store encrypted messages
10460 If you do, anybody who has access to your mail folders can read them,
10461 but if you do not, you might be unable to read them yourself later if
10462 you happen to lose your private key.
10465 command saves messages in decrypted form, while the
10469 commands leave them encrypted.
10472 Note that neither S/MIME signing nor encryption applies to message
10473 subjects or other header fields yet.
10474 Thus they may not contain sensitive information for encrypted messages,
10475 and cannot be trusted even if the message content has been verified.
10476 When sending signed messages,
10477 it is recommended to repeat any important header information in the
10481 .\" .Ss "Using CRLs with S/MIME or SSL/TLS" {{{
10482 .Ss "Using CRLs with S/MIME or SSL/TLS"
10484 \*(OP Certification authorities (CAs) issue certificate revocation
10485 lists (CRLs) on a regular basis.
10486 These lists contain the serial numbers of certificates that have been
10487 declared invalid after they have been issued.
10488 Such usually happens because the private key for the certificate has
10490 because the owner of the certificate has left the organization that is
10491 mentioned in the certificate, etc.
10492 To seriously use S/MIME or SSL/TLS verification,
10493 an up-to-date CRL is required for each trusted CA.
10494 There is otherwise no method to distinguish between valid and
10495 invalidated certificates.
10496 \*(UA currently offers no mechanism to fetch CRLs, nor to access them on
10497 the Internet, so you have to retrieve them by some external mechanism.
10500 \*(UA accepts CRLs in PEM format only;
10501 CRLs in DER format must be converted, like, e.\|g.:
10504 .Dl $ openssl crl \-inform DER \-in crl.der \-out crl.pem
10507 To tell \*(UA about the CRLs, a directory that contains all CRL files
10508 (and no other files) must be created.
10513 variables, respectively, must then be set to point to that directory.
10514 After that, \*(UA requires a CRL to be present for each CA that is used
10515 to verify a certificate.
10518 .\" .Ss "Handling spam" {{{
10519 .Ss "Handling spam"
10521 \*(OP \*(UA can make use of several spam interfaces for the purpose of
10522 identification of, and, in general, dealing with spam messages.
10523 A precondition of most commands in order to function is that the
10525 variable is set to one of the supported interfaces.
10526 Once messages have been identified as spam their (volatile)
10528 state can be prompted: the
10532 message specifications will address respective messages and their
10534 entries will be used when displaying the
10536 in the header display.
10541 rates the given messages and sets their
10544 If the spam interface offers spam scores those can also be displayed in
10545 the header display by including the
10555 will interact with the Bayesian filter of the chosen interface and learn
10556 the given messages as
10560 respectively; the last command can be used to cause
10562 of messages; it adheres to their current
10564 state and thus reverts previous teachings.
10569 will simply set and clear, respectively, the mentioned volatile
10571 message flag, without any interface interaction.
10580 requires a running instance of the
10582 server in order to function, started with the option
10584 shall Bayesian filter learning be possible.
10586 .Bd -literal -offset indent
10587 $ spamd -i localhost:2142 -i /tmp/.spamsock -d [-L] [-l]
10588 $ spamd --listen=localhost:2142 --listen=/tmp/.spamsock \e
10589 --daemonize [--local] [--allow-tell]
10593 Thereafter \*(UA can make use of these interfaces:
10595 .Bd -literal -offset indent
10596 $ \*(uA -Sspam-interface=spamc -Sspam-maxsize=500000 \e
10597 -Sspamc-command=/usr/local/bin/spamc \e
10598 -Sspamc-arguments="-U /tmp/.spamsock" -Sspamc-user=
10600 $ \*(uA -Sspam-interface=spamc -Sspam-maxsize=500000 \e
10601 -Sspamc-command=/usr/local/bin/spamc \e
10602 -Sspamc-arguments="-d localhost -p 2142" -Sspamc-user=
10606 Using the generic filter approach allows usage of programs like
10608 Here is an example, requiring it to be accessible via
10611 .Bd -literal -offset indent
10612 $ \*(uA -Sspam-interface=filter -Sspam-maxsize=500000 \e
10613 -Sspamfilter-ham="bogofilter -n" \e
10614 -Sspamfilter-noham="bogofilter -N" \e
10615 -Sspamfilter-nospam="bogofilter -S" \e
10616 -Sspamfilter-rate="bogofilter -TTu 2>/dev/null" \e
10617 -Sspamfilter-spam="bogofilter -s" \e
10618 -Sspamfilter-rate-scanscore="1;^(.+)$"
10622 Because messages must exist on local storage in order to be scored (or
10623 used for Bayesian filter training), it is possibly a good idea to
10624 perform the local spam check last:
10626 .Bd -literal -offset indent
10627 define spamdelhook {
10629 spamset (header x-dcc-brand-metrics "bulk")
10630 # Server-side spamassassin(1)
10631 spamset (header x-spam-flag "YES")
10632 del :s # TODO we HAVE to be able to do `spamrate :u ! :sS'
10633 move :S +maybe-spam
10636 move :S +maybe-spam
10638 set folder-hook-FOLDER=spamdelhook
10642 See also the documentation for the variables
10643 .Va spam-interface , spam-maxsize ,
10644 .Va spamc-command , spamc-arguments , spamc-user ,
10645 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
10648 .Va spamfilter-rate-scanscore .
10656 In general it is a good idea to turn on
10662 twice) if something does not work well.
10663 Very often a diagnostic message can be produced that leads to the
10664 problems' solution.
10666 .\" .Ss "\*(UA shortly hangs on startup" {{{
10667 .Ss "\*(UA shortly hangs on startup"
10669 This can have two reasons, one is the necessity to wait for a file lock
10670 and cannot be helped, the other being that \*(UA calls the function
10672 in order to query the nodename of the box (sometimes the real one is
10673 needed instead of the one represented by the internal variable
10675 You may have varying success by ensuring that the real hostname and
10679 or, more generally, that the name service is properly setup \(en
10682 return what you would expect?
10683 Does this local hostname has a domain suffix?
10684 RFC 6762 standardized the link-local top-level domain
10686 try again after adding an (additional) entry with this extension.
10689 .\" .Ss "\*(UA exits quick, and output is cleared away" {{{
10690 .Ss "\*(UA exits quick, and output is cleared away"
10692 When this happens even with
10694 set, then this most likely indicates a problem with the creation of
10695 so-called dotlock files: setting
10696 .Va dotlock-ignore-error
10697 should overcome this situation.
10698 This only avoids symptoms, it does not address the problem, though.
10699 Since the output is cleared away \*(UA has support for
10700 .Sx "On terminal control and line editor" ,
10701 and switches to the
10703 which causes the output clearance: by doing
10704 .Ql set termcap='smcup='
10705 this mode can be suppressed, and by setting
10707 (twice) the actual problem should be reported.
10710 .\" .Ss "I cannot login to Google mail aka GMail" {{{
10711 .Ss "I cannot login to Google mail aka GMail"
10713 Since 2014 some free service providers classify programs as
10715 unless they use a special authentification method (OAuth 2.0) which
10716 was not standardized for non-HTTP protocol authentication token query
10717 until August 2015 (RFC 7628).
10720 Different to Kerberos / GSSAPI, which is developed since the mid of the
10721 1980s, where a user can easily create a local authentication ticket for
10722 her- and himself with the locally installed
10724 program, that protocol has no such local part but instead requires
10725 a world-wide-web query to create or fetch a token; since there is no
10726 local cache this query would have to be performed whenever \*(UA is
10727 invoked (in interactive sessions situation may differ).
10730 \*(UA does not support OAuth.
10731 Because of this it is necessary to declare \*(UA a
10732 .Dq less secure app
10733 (on the providers account web page) in order to read and send mail.
10734 However, it also seems possible to take the following steps instead:
10739 give the provider the number of a mobile phone,
10742 .Dq 2-Step Verification ,
10744 create an application specific password (16 characters), and
10746 use that special password instead of your real Google account password in
10747 \*(UA (for more on that see the section
10748 .Sx "On URL syntax and credential lookup" ) .
10752 .\" .Ss "Not \(dqdefunctional\(dq, but the editor key does not work" {{{
10753 .Ss "Not \(dqdefunctional\(dq, but the editor key does not work"
10755 It can happen that the terminal library (see
10756 .Sx "On terminal control and line editor",
10759 reports different codes than the terminal really sends, in which case
10760 \*(UA will tell that a key binding is functional, but will not be able to
10761 recognize it because the received data does not match anything expected.
10766 ings will show the byte sequences that are expected.
10769 To overcome the situation, use, e.g., the program
10771 in conjunction with the
10773 flag if available, to see the byte sequences which are actually produced
10774 by keypresses, and use the variable
10776 to make \*(UA aware of them.
10777 E.g., the terminal this is typed on produces some false sequences, here
10778 an example showing the shifted home key:
10780 .Bd -literal -offset indent
10783 # 1B 5B=[ 31=1 3B=; 32=2 48=H
10788 ? \*(uA -v -Stermcap='kHOM=\eE[H'
10797 .\" .Sh "SEE ALSO" {{{
10807 .Xr spamassassin 1 ,
10816 .Xr mailwrapper 8 ,
10821 .\" .Sh HISTORY {{{
10824 M. Douglas McIlroy writes in his article
10825 .Dq A Research UNIX Reader: Annotated Excerpts \
10826 from the Programmer's Manual, 1971-1986
10829 command already appeared in First Edition
10833 .Bd -ragged -offset indent
10834 Electronic mail was there from the start.
10835 Never satisfied with its exact behavior, everybody touched it at one
10836 time or another: to assure the safety of simultaneous access, to improve
10837 privacy, to survive crashes, to exploit uucp, to screen out foreign
10838 freeloaders, or whatever.
10839 Not until v7 did the interface change (Thompson).
10840 Later, as mail became global in its reach, Dave Presotto took charge and
10841 brought order to communications with a grab-bag of external networks
10847 Mail was written in 1978 by Kurt Shoens and developed as part of the
10850 distribution until 1995.
10851 Mail has then seen further development in open source
10853 variants, noticeably by Christos Zoulas in
10855 Basing upon this Nail, later Heirloom Mailx, was developed by Gunnar
10856 Ritter in the years 2000 until 2008.
10857 Since 2012 S-nail is maintained by Steffen (Daode) Nurpmeso.
10858 This man page is derived from
10859 .Dq The Mail Reference Manual
10860 that was originally written by Kurt Shoens.
10866 .An "Kurt Shoens" ,
10867 .An "Edward Wang" ,
10868 .An "Keith Bostic" ,
10869 .An "Christos Zoulas" ,
10870 .An "Gunnar Ritter" ,
10871 .An "Steffen Nurpmeso" Aq Mt s-nail-users@lists.sourceforge.net
10873 .Mt s-mailx@sdaoden.eu ) .
10876 .\" .Sh CAVEATS {{{
10879 \*(ID Interrupting an operation via
10883 is often problematic: many library functions cannot deal with the
10885 that this software (still) performs.
10888 The SMTP and POP3 protocol support of \*(UA is very basic.
10889 Also, if it fails to contact its upstream SMTP server, it will not make
10890 further attempts to transfer the message at a later time (setting
10895 If this is a concern, it might be better to set up a local SMTP server
10896 that is capable of message queuing.
10902 After deleting some message of a POP3 mailbox the header summary falsely
10903 claims that there are no messages to display, you need to perform
10904 a scroll or dot movement to restore proper state.
10906 In threaded display a power user may encounter crashes very
10907 occasionally (this is may and very).
10911 in the source repository lists future directions.