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 ".Fl _ Ar _ddr"
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.
194 Being a special incarnation of
196 macros for the purpose of bundling longer-lived settings, activating
197 such an email account also switches to the accounts system
206 The same filename conventions as described in the section
208 apply: shell word expansion is restricted to the tilde
212 not be accessible but contain a
214 character, then anything after the
216 is assumed to specify the input character set and anything before
218 the filename: this is the only option to specify (and fixate) the input
219 character set of text attachments from the command line, not using the
221 command of and in the compose mode that follows
223 .Sx "COMMAND ESCAPES"
224 for compose mode commands).
228 (\*(OB: \*(UA will always use line-buffered output, to gain
229 line-buffered input even in batch mode enable batch mode via
234 Send a blind carbon copy to
237 May be used multiple times.
239 .Sx "On sending mail, and non-interactive mode" .
243 Send carbon copies to the given receiver.
244 May be used multiple times.
249 the internal variable
251 which enables debug messages and disables message delivery,
252 among others; effectively turns almost any operation into a dry-run.
258 and thus discard messages with an empty message part body.
259 This command line flag is \*(OB.
263 Just check if mail is present (in the specified or system
265 if yes, return an exit status of zero, a non-zero value otherwise.
266 To restrict the set of mails to consider in this evaluation a message
267 specification can be added with the option
272 Save the message to send in a file named after the local part of the
273 first recipient's address (instead of in
278 Read in the contents of the user's
280 (or the specified file) for processing;
281 when \*(UA is quit, it writes undeleted messages back to this file
285 Some special conventions are recognized for the optional
287 argument which are documented for the
292 is not a argument to the flag
294 but is instead taken from the command line after option processing has
298 that starts with a hyphen, prefix it with a (relative) path, as in
299 .Ql ./-hyphenbox.mbox .
303 Display a summary of the
305 of all messages in the specified mailbox or system
308 A configurable summary view is available via the
314 Show a short usage summary.
315 Because of widespread use a
317 argument will have the same effect.
323 to ignore tty interrupt signals.
326 .It Fl L Ar spec-list
327 Display a summary of all
329 of only those messages in the specified mailbox or the system
335 .Sx "Specifying messages"
342 option has been given in addition no header summary is produced,
343 but \*(UA will instead indicate via its exit status whether
349 note that any verbose output is suppressed in this mode and must instead
350 be enabled explicitly (e.g., by using the option
355 Special send mode that will flag standard input with the MIME
359 and use it as the main message body.
360 \*(ID Using this option will bypass processing of
361 .Va message-inject-head ,
364 .Va message-inject-tail .
370 Special send mode that will MIME classify the specified
372 and use it as the main message body.
373 \*(ID Using this option will bypass processing of
374 .Va message-inject-head ,
377 .Va message-inject-tail .
385 and thus inhibit initial display of message headers when reading mail or
386 editing a mail folder.
390 Standard flag that inhibits reading the system wide
395 allows more control over the startup sequence; also see
396 .Sx "Resource files" .
400 Special send mode that will initialize the message body with the
401 contents of the specified
403 which may be standard input
405 only in non-interactive context.
411 Any folder opened will be in read-only mode.
415 .It Fl r Ar from-addr
416 The source address that appears in the
419 header of a message (or in the
422 header if the former contains multiple addresses) is not used for
423 relaying and delegating a message over the wire via SMTP, but instead an
424 envelope will enwrap the message content and provide the necessary
425 information (i.e., the RFC 5321 reverse-path, also used to report, e.g.,
426 delivery errors) to transmit the message to its destination(s).
427 Whereas the said headers and internal variables will be used by \*(UA to
428 create the envelope if the builtin SMTP
430 (Mail-Transfer-Agent) is used, a file-based MTA will instead use the
431 identity of the message-originating user.
433 This command line option can be used to specify the reverse-path, to be
434 passed to a file-based
436 when a message is sent, via
437 .Ql -f Ar from-addr .
440 include a user name, then the address components will be separated and
441 the name part will be passed to a file-based
447 is also assigned to the internal variable
449 Many default installations and sites disallow explicit overriding of the
450 user identity which could be adjusted by this option, unless either
452 has been configured accordingly, or the user is member of a group with
453 special privileges, respectively.
455 If an empty string is passed as
457 then the content of the variable
459 (or, if that contains multiple addresses,
461 will be evaluated and used for this purpose whenever the file-based
464 Note that \*(UA by default, without
466 that is, neither passes
470 flags to a file-based MTA by itself, unless this automatic deduction is
473 ing the internal variable
474 .Va r-option-implicit .
478 .It Fl S Ar var Ns Op = Ns value
482 iable and, in case of a non-boolean variable which has a value, assign
486 .Sx "INTERNAL VARIABLES"
490 may be overwritten from within resource files,
491 the command line setting will be reestablished after all resource files
496 Specify the subject of the message to be sent.
497 Newline (NL) and carriage-return (CR) bytes are invalid and will be
498 normalized to space (SP) characters.
502 The message given (on standard input) is expected to contain, separated
503 from the message body by an empty line, a message header with
508 fields giving its recipients, which will be added to any recipients
509 specified on the command line.
510 If a message subject is specified via
512 then it will be used in favour of one given on the command line.
528 .Ql Mail-Followup-To: ,
529 by default created automatically dependent on message context, will
530 be used if specified (a special address massage will however still occur
532 Any other (also custom) header field is passed through entirely
533 unchanged, and in conjunction with the option
535 it is possible to embed
536 .Sx "COMMAND ESCAPES" .
542 Initially read the primary system mailbox of
544 appropriate privileges presumed; effectively identical to
554 will also show the list of
556 .Ql $ \*(uA -Xversion -Xx .
561 ting the internal variable
563 enables display of some informational context messages.
564 Using it twice increases the level of verbosity.
568 Add the given (or multiple for a multiline argument)
570 to the list of commands to be executed (as a unit, just as via
572 before normal operation starts.
576 .Va batch-exit-on-error ;
577 the only possibility to execute commands in non-interactive mode when
578 reading startup files is actively prohibited.
583 .Sx "COMMAND ESCAPES"
584 even if not in interactive mode.
585 This can be used to, e.g., automatically format the composed message
586 text before sending the message:
587 .Bd -literal -offset indent
588 $ ( echo 'line one. Word. Word2.'; \e
589 echo '~| /usr/bin/fmt -tuw66' ) |\e
590 LC_ALL=C \*(uA -:/ -Sttycharset=UTF-8 -d~ bob@exam.ple
596 In batch mode the full set of commands is available, just like in
597 interactive mode, standard input is made line buffered, and diverse
598 .Sx "INTERNAL VARIABLES"
599 are adjusted for batch necessities, e.g., it
615 .Sx "COMMAND ESCAPES"
616 is enabled in compose mode.
617 The following prepares an email message in a batched dry run:
618 .Bd -literal -offset indent
619 $ LC_ALL=C printf 'm bob\en~s ubject\enText\en~.\enx\en' | \e
620 LC_ALL=C \*(uA -:/ -d# -X'alias bob bob@exam.ple'
625 This flag forces termination of option processing in order to prevent
628 It also forcefully puts \*(UA into send mode, see
629 .Sx "On sending mail, and non-interactive mode" .
633 In the above list of supported command line options,
637 are implemented by means of
639 ting the respective internal variable, as via
642 .Op Ar mta-option ...
644 arguments that are given at the end of the command line after a
646 separator will be passed through to a file-based
648 (Mail-Transfer-Agent) and persist for an entire (interactive) session
649 \(en if the setting of
651 allows their recognition; no such constraints apply to the variable
655 .\" .Ss "A starter" {{{
658 \*(UA is a direct descendant of
660 Mail, a successor of the Research
663 .Dq was there from the start
668 Mail reference manual begins with the following words:
670 .Bd -ragged -offset indent
671 Mail provides a simple and friendly environment for sending and
673 It divides incoming mail into its constituent messages and allows the
674 user to deal with them in any order.
675 In addition, it provides a set of
677 -like commands for manipulating messages and sending mail.
678 Mail offers the user simple editing capabilities to ease the composition
679 of outgoing messages, as well as providing the ability to define and
680 send to names which address groups of users.
684 \*(UA is thus the user side of the
686 mail system, whereas the system side (Mail-Transfer-Agent, MTA) was
687 traditionally taken by
689 and most MTAs provide a binary of this name for compatibility purposes.
694 of \*(UA then the system side is not a mandatory precondition for mail
698 Because \*(UA strives for compliance with POSIX
700 it is likely that some configuration settings have to be adjusted before
701 using it is a smooth experience.
704 resource file bends those standard imposed settings of the
705 .Sx "INTERNAL VARIABLES"
706 a bit towards more user friendliness and safety, however, e.g., it
711 in order to suppress the automatic moving of messages to
713 that would otherwise occur (see
714 .Sx "Message states" ) ,
717 to not remove empty system (MBOX) mailbox files in order not to mangle
718 file permissions when files eventually get recreated; be aware that
719 \*(UA will (try to) remove all empty (MBOX) mailbox files unless this
720 variable is set in case
722 .Pf ( Ev POSIXLY_CORRECT )
723 mode has been enabled.
724 The file mode creation mask is explicitly managed via
730 in order to synchronize \*(UA with the exit status report of the used
735 to enter interactive startup even if the initial mailbox is empty,
737 to allow editing of headers as well as
739 to not strip down addresses in compose mode, and
741 to include the message that is being responded to when
746 contains some more complete configuration examples.
749 .\" .Ss "On sending mail, and non-interactive mode" {{{
750 .Ss "On sending mail, and non-interactive mode"
752 To send a message to one or more people, using a local or a builtin
754 (Mail-Transfer-Agent) transport to actually deliver the generated mail
755 message, \*(UA can be invoked with arguments which are the names of
756 people to whom the mail will be sent, and the command line options
760 can be used to add (blind) carbon copy receivers:
762 .Bd -literal -offset indent
763 $ \*(uA -s ubject -a ttach.txt bill@exam.ple
764 # But... try it in an isolated dry-run mode first
765 $ LC_ALL=C \*(uA -:/ -d -vv -Ssendwait \e
766 -b bcc@exam.ple -c cc@exam.ple -. \e
767 '(Lovely) Bob <bob@exam.ple>' eric@exam.ple
769 $ LC_ALL=C \*(uA -:/ -d -vv -Sv15-compat -Ssendwait \e
770 -S 'mta=smtps://mylogin@exam.ple:465' -Ssmtp-auth=login \e
771 -S 'from=scriptreply@exam.ple' \e
777 If standard input is a terminal rather than the message to be sent,
778 the user is expected to type in the message contents.
779 In this compose mode \*(UA treats lines beginning with the character
781 special \(en these are so-called
782 .Sx "COMMAND ESCAPES"
783 which can be used to read in files, process shell commands, add and edit
784 attachments and more; e.g., the command escape
786 will start the text editor to revise the message in its current state,
788 allows editing of the most important message headers and
790 gives an overview of available command escapes.
794 at the beginning of an empty line leaves compose mode and causes the
795 message to be sent, whereas typing
798 twice will abort the current letter (saving its contents in the file
804 Messages are sent asynchronously, without supervision, unless the variable
806 is set, therefore send errors are not recognizable until then.
812 .Sx "INTERNAL VARIABLES"
813 can be used to alter default behavior; e.g.,
818 will automatically startup a text editor when compose mode is entered,
820 allows editing of headers additionally to plain body content,
822 will cause the user to be prompted actively for carbon-copy recipients
825 will allow leaving compose mode by writing a line consisting solely of
831 hook macros may be set to automatically adjust some settings dependent
832 on receiver, sender or subject contexts, and
833 .Va on-compose-done-shell
836 are increasingly powerful mechanisms to perform automated message
837 adjustments in between.
840 Especially for using public mail provider accounts with the SMTP
842 it is often necessary to set
844 and saving a copy of sent messages in a
846 may be desirable \(en as for most mailbox file targets some special
847 syntax conventions are recognized (see the
849 command for more on that).
852 for the purpose of arranging a complete environment of settings that can
853 be switched to with a single command or command line option may be
856 contains example configurations for sending messages via some of the
857 well-known public mail providers and also gives a compact overview on
858 how to setup a secure SSL/TLS environment).
863 sandbox dry-run tests first will prove correctness.
867 .Sx "On URL syntax and credential lookup"
868 will spread light on the different ways of how to specify user email
869 account credentials, the
871 variable chains, and accessing protocol-specific resources,
874 goes into the details of character encoding and how to use them for
875 representing messages and MIME part contents by specifying them in
877 and reading the section
878 .Sx "The mime.types files"
879 should help to understand how the MIME-type of outgoing attachments are
880 classified, and what can be done for fine-tuning.
881 Over the wire an intermediate, configurable
882 .Pf content-transfer-\: Va encoding
883 may be applied to the raw message part data.
886 Message recipients (as specified on the command line or defined in
891 may not only be email addressees but can also be names of mailboxes and
892 even complete shell command pipe specifications.
895 is not set then only network addresses (see
897 for a description of mail addresses) and plain user names (including MTA
898 aliases) may be used, other types will be filtered out, giving a warning
901 .\" When changing any of the following adjust any RECIPIENTADDRSPEC;
902 .\" grep the latter for the complete picture
906 is set then extended recipient addresses will optionally be accepted:
907 Any name which starts with a vertical bar
909 character specifies a command pipe \(en the command string following the
911 is executed and the message is sent to its standard input;
912 Likewise, any name that starts with the character solidus
914 or the character sequence dot solidus
916 is treated as a file, regardless of the remaining content;
917 likewise a name that solely consists of a hyphen
919 Any other name which contains an at sign
921 character is treated as a network address;
922 Any other name which starts with a plus sign
924 character specifies a mailbox name;
925 Any other name which contains a solidus
927 character but no exclamation mark
931 character before also specifies a mailbox name;
932 What remains is treated as a network address.
934 .Bd -literal -offset indent
935 $ echo bla | \*(uA -Sexpandaddr -s test ./mbox.mbox
936 $ echo bla | \*(uA -Sexpandaddr -s test '|cat >> ./mbox.mbox'
937 $ echo safe | LC_ALL=C \e
938 \*(uA -:/ -Sv15-compat -Ssendwait -Snosave \e
939 -Sexpandaddr=fail,-all,+addr -s test \e
944 It is possible to create personal distribution lists via the
946 command, so that, for instance, the user can send mail to
948 and have it go to a group of people.
949 These aliases have nothing in common with the system wide aliases that
950 may be used by the MTA, which are subject to the
954 and are often tracked in a file
960 Personal aliases will be expanded by \*(UA before the message is sent,
961 and are thus a convenient alternative to specifying each addressee by
965 .Dl alias cohorts bill jkf mark kridle@ucbcory ~/mail/cohorts.mbox
968 To avoid environmental noise scripts should
970 \*(UA from any configuration files and create a script-local
971 environment, ideally with the command line options
973 to disable any configuration file in conjunction with repetitions of
975 to specify variables:
977 .Bd -literal -offset indent
978 $ env LC_ALL=C \*(uA -:/ \e
979 -Sv15-compat -Ssendwait -Snosave -Sttycharset=utf-8 \e
980 -Sexpandaddr=fail,-all,+addr \e
981 -S 'mta=smtps://mylogin@exam.ple:465' -Ssmtp-auth=login \e
982 -S 'from=scriptreply@exam.ple' \e
983 -s 'subject' -a attachment_file \e
984 -. "Recipient 1 <rec1@exam.ple>" rec2@exam.ple \e
989 As shown, scripts can
991 a locale environment, the above specifies the all-compatible 7-bit clean
994 but will nonetheless take and send UTF-8 in the message text by using
996 In interactive mode, which is introduced in the next section, messages
997 can be sent by calling the
999 command with a list of recipient addresses \(em the semantics are
1000 completely identical to non-interactive message sending:
1002 .Bd -literal -offset indent
1003 $ \*(uA -d -Squiet -Semptystart
1004 "/var/spool/mail/user": 0 messages
1005 ? mail "Recipient 1 <rec1@exam.ple>", rec2@exam.ple
1006 ? # Will do the right thing (tm)
1007 ? m rec1@exam.ple rec2@exam.ple
1011 .\" .Ss "On reading mail, and interactive mode" {{{
1012 .Ss "On reading mail, and interactive mode"
1014 When invoked without addressees \*(UA enters interactive mode in which
1016 When used like that the user's system
1020 for an in-depth description of the different mailbox types that exist)
1021 is read in and a one line header of each message therein is displayed.
1022 The visual style of this summary of
1024 can be adjusted through the variable
1026 and the possible sorting criterion via
1032 can be performed with the command
1034 If the initially opened mailbox is empty \*(UA will instead exit
1035 immediately (after displaying a message) unless the variable
1044 will give a listing of all available commands and
1046 will give a summary of some common ones.
1047 If the \*(OPal documentation strings are available one can type
1050 and see the actual expansion of
1052 and what its purpose is, i.e., commands can be abbreviated
1053 (note that POSIX defines some abbreviations, so that the alphabetical
1054 order of commands does not necessarily relate to the abbreviations; it is
1055 possible to define overwrites with the
1058 These commands can also produce a more
1063 Messages are given numbers (starting at 1) which uniquely identify
1064 messages; the current message \(en the
1066 \(en will either be the first new message, or the first unread message,
1067 or the first message of the mailbox; the internal variable
1069 will instead cause usage of the last message for this purpose.
1074 ful of header summaries containing the
1078 will display only the summaries of the given messages, defaulting to the
1082 Message content can be displayed on the users' terminal with the
1086 If instead the command
1088 is used, only the first
1090 of a message will be shown.
1091 By default the current message
1093 is displayed, but like with many other commands it is possible to give
1094 a fancy message specification (see
1095 .Sx "Specifying messages" ) ,
1098 will display all unread messages,
1103 will type the messages 1 and 5,
1105 will type the messages 1 through 5, and
1109 will display the last and the next message, respectively.
1112 (a more substantial alias of the standard command
1114 will display a header summary of the given message specification list
1115 instead of their content, e.g., the following will search for subjects:
1118 .Dl from "'@Some subject to search for'"
1121 In the default setup all header fields of a message will be
1123 d, but fields can be white- or blacklisted for a variety of
1124 applications by using the command
1126 e.g., to restrict display to a very restricted set:
1127 .Ql Ic \:headerpick Cd \:type retain add Ar \:from to cc subject .
1128 In order to display all header fields of a message regardless of
1129 currently active ignore or retain lists, use the commands
1135 controls whether and when \*(UA will use the configured
1137 for display instead of directly writing to the user terminal
1139 (generally speaking).
1140 Note that historically the global
1142 not only adjusts the list of displayed headers, but also sets
1146 Dependent upon the configuration a line editor (see the section
1147 .Sx "On terminal control and line editor" )
1148 aims at making user experience with the many
1151 When reading the system
1157 specified a mailbox explicitly prefixed with the special
1159 modifier (propagating the mailbox to a primary one) then messages which
1160 have been read will be moved to a secondary mailbox, the user's
1162 file, automatically when the mailbox is left, either by changing the
1163 active mailbox or by quitting \*(UA (also see
1164 .Sx "Message states" )
1165 \(en this automatic moving from a system or primary to the secondary
1166 mailbox is not performed when the variable
1171 After examining a message the user can also
1175 to the sender and all recipients or
1177 exclusively to the sender(s).
1178 Messages can also be
1180 ed (shorter alias is
1182 Note that when replying to or forwarding a message recipient addresses
1183 will be stripped from comments and names unless the internal variable
1186 Deletion causes \*(UA to forget about the message;
1187 This is not irreversible, though, one can
1189 the message by giving its number,
1190 or the \*(UA session can be ended by giving the
1195 To end a mail processing session one may either issue
1197 to cause a full program exit, which possibly includes
1198 automatic moving of read messages to
1200 as well as updating the \*(OPal line editor
1204 instead in order to prevent any of these actions.
1207 .\" .Ss "HTML mail and MIME attachments" {{{
1208 .Ss "HTML mail and MIME attachments"
1210 Messages which are HTML-only get more and more common and of course many
1211 messages come bundled with a bouquet of MIME attachments.
1212 Whereas \*(UA \*(OPally supports a simple HTML-to-text converter to deal
1213 with HTML messages (see
1214 .Sx "The mime.types files" ) ,
1215 it normally cannot deal with any of these itself, but instead programs
1216 need to become registered to deal with specific MIME types or file
1218 These programs may either prepare plain text versions of their input
1219 in order to enable \*(UA to display the content on the terminal,
1220 or display the content themselves, for example in a graphical window.
1223 To install an external handler program for a specific MIME type set an
1225 .Va pipe-TYPE/SUBTYPE
1226 variable; to instead define a handler for a specific file extension set
1229 variable \(en these handlers take precedence.
1230 \*(OPally \*(UA supports mail user agent configuration as defined in
1231 RFC 1524; this mechanism, documented in the section
1232 .Sx "The Mailcap files" ,
1233 will be queried for display or quote handlers if none of the former two
1234 .\" TODO v15-compat "will be" -> "is"
1235 did; it will be the sole source for handlers of other purpose.
1236 A last source for handlers may be the MIME type definition itself, if
1237 the \*(UA specific type-marker extension was used when defining the type
1240 (Many of the builtin MIME types do so by default.)
1244 .Va mime-counter-evidence
1245 can be set to improve dealing with faulty MIME part declarations as are
1246 often seen in real-life messages.
1247 E.g., to display a HTML message inline (that is, converted to a more
1248 fancy plain text representation than the builtin converter is capable to
1249 produce) with either of the text-mode browsers
1253 teach \*(UA about MathML documents and make it display them as plain
1254 text, and to open PDF attachments in an external PDF viewer,
1255 asynchronously and with some other magic attached:
1257 .Bd -literal -offset indent
1258 if $features !@ +filter-html-tagsoup
1259 #set pipe-text/html='elinks -force-html -dump 1'
1260 set pipe-text/html='lynx -stdin -dump -force_html'
1261 # Display HTML as plain text instead
1262 #set pipe-text/html=@
1264 mimetype '@ application/mathml+xml mathml'
1265 wysh set pipe-application/pdf='@&=@ \e
1266 trap "rm -f \e"${NAIL_FILENAME_TEMPORARY}\e"" EXIT;\e
1267 trap "trap \e"\e" INT QUIT TERM; exit 1" INT QUIT TERM;\e
1268 mupdf "${NAIL_FILENAME_TEMPORARY}"'
1272 Note: special care must be taken when using such commands as mail
1273 viruses may be distributed by this method: if messages of type
1274 .Ql application/x-sh
1275 or files with the extension
1277 were blindly filtered through the shell, for example, a message sender
1278 could easily execute arbitrary code on the system \*(UA is running on.
1279 For more on MIME, also in respect to sending of messages, see the
1281 .Sx "The mime.types files" ,
1282 .Sx "The Mailcap files"
1287 .\" .Ss "Mailing lists" {{{
1290 \*(UA offers some support to ease handling of mailing lists.
1293 promotes all given arguments to known mailing lists, and
1295 sets their subscription attribute, creating them first as necessary.
1300 automatically, but only resets the subscription attribute.)
1301 Using the commands without arguments will show (a subset of) all
1302 currently defined mailing lists.
1307 can be used to mark out messages with configured list addresses
1308 in the header display.
1311 \*(OPally mailing lists may also be specified as (extended) regular
1312 expressions, which allows matching of many addresses with a single
1314 However, all fully qualified list addresses are matched via a fast
1315 dictionary, whereas expressions are placed in (a) list(s) which is
1316 (are) matched sequentially.
1318 .Bd -literal -offset indent
1319 set followup-to followup-to-honour=ask-yes reply-to-honour=ask-yes
1320 wysh mlist a1@b1.c1 a2@b2.c2 '.*@lists\e.c3$'
1321 mlsubscribe a4@b4.c4 exact@lists.c3
1326 .Va followup-to-honour
1328 .Ql Mail-\:Followup-\:To:
1329 header is honoured when the message is being replied to (via
1335 controls whether this header is created when sending mails; it will be
1336 created automatically for a couple of reasons, too, like when the
1338 .Dq mailing list specific
1343 is used to respond to a message with its
1344 .Ql Mail-Followup-To:
1348 A difference in between the handling of known and subscribed lists is
1349 that the address of the sender is usually not part of a generated
1350 .Ql Mail-Followup-To:
1351 when addressing the latter, whereas it is for the former kind of lists.
1352 Usually because there are exceptions: say, if multiple lists are
1353 addressed and not all of them are subscribed lists.
1355 For convenience \*(UA will, temporarily, automatically add a list
1356 address that is presented in the
1358 header of a message that is being responded to to the list of known
1360 Shall that header have existed \*(UA will instead, dependent on the
1362 .Va reply-to-honour ,
1365 for this purpose in order to accept a list administrators' wish that
1366 is supposed to have been manifested like that (but only if it provides
1367 a single address which resides on the same domain as what is stated in
1371 .\" .Ss "Resource files" {{{
1372 .Ss "Resource files"
1374 Upon startup \*(UA reads in several resource files:
1376 .Bl -tag -width ".It Pa _AIL_EXTRA_R_"
1379 System wide initialization file.
1380 Reading of this file can be suppressed, either by using the
1384 command line options, or by setting the
1387 .Ev NAIL_NO_SYSTEM_RC .
1391 File giving initial commands.
1392 A different file can be chosen by setting the
1396 Reading of this file can be suppressed with the
1398 command line option.
1400 .It Va NAIL_EXTRA_RC
1401 Can be used to define an optional startup file to be read after all
1402 other resource files.
1403 It can be used to specify settings that are not understood by other
1405 implementations, for example.
1406 This variable is only honoured when defined in a resource file, e.g.,
1408 .Sx "INTERNAL VARIABLES" .
1412 The content of these files is interpreted as follows:
1415 .Bl -bullet -compact
1417 A lines' leading whitespace is removed.
1419 Empty lines are ignored.
1421 Any other line is interpreted as a command.
1422 It may be spread over multiple input lines if the newline character is
1424 by placing a reverse solidus character
1426 as the last character of the line; whereas any leading whitespace of
1427 follow lines is ignored, trailing whitespace before a escaped newline
1428 remains in the input.
1430 If the line (content) starts with the number sign
1432 then it is a comment-command \(en a real command! \(en and also ignored.
1433 This command is the only form of comment that is understood.
1437 Unless \*(UA is about to enter interactive mode syntax errors that occur
1438 while loading these files are treated as errors and cause program exit.
1439 More files with syntactically equal content can be
1441 The following, saved in a file, would be an examplary content:
1443 .Bd -literal -offset indent
1444 # This line is a comment command. And y\e
1445 es, it is really continued here.
1452 .\" .Ss "Character sets" {{{
1453 .Ss "Character sets"
1455 \*(OP \*(UA detects the character set of the terminal by using
1456 mechanisms that are controlled by the
1461 should give an overview); the \*(UA internal variable
1463 will be set to the detected terminal character set accordingly
1464 and will thus show up in the output of the commands
1470 However, a user supplied
1472 value is not overwritten by this detection mechanism: this
1474 must be used if the detection does not work properly,
1475 and it may be used to adjust the name of the locale character set.
1476 E.g., on BSD systems one may use a locale with the character set
1477 ISO8859-1, which is not a valid name for this character set; to be on
1478 the safe side, one may set
1480 to the correct name, which is ISO-8859-1.
1483 Note that changing the value does not mean much beside that,
1484 since several aspects of the real character set are implied by the
1485 locale environment of the system,
1486 and that stays unaffected by the content of an overwritten
1489 (This is mostly an issue when interactively using \*(UA, though.
1490 It is actually possible to send mail in a completely
1492 locale environment, an option that \*(UA's test-suite uses excessively.)
1495 If no character set conversion capabilities have been compiled into
1498 does not include the term
1502 will be the only supported character set,
1503 it is simply assumed that it can be used to exchange 8-bit messages
1504 (over the wire an intermediate
1505 .Pf content-transfer-\: Va encoding
1507 and the rest of this section does not apply;
1508 it may however still be necessary to explicitly set it if automatic
1509 detection fails, since in that case it defaults to the mentioned
1510 .\" (Keep in SYNC: ./nail.1:"Character sets", ./nail.h:CHARSET_*!)
1514 When reading messages, their text is converted into
1516 as necessary in order to display them on the users terminal.
1517 Unprintable characters and invalid byte sequences are detected
1518 and replaced by proper substitution characters (unless the variable
1520 was set once \*(UA was started).
1522 .Va charset-unknown-8bit
1523 to deal with another hairy aspect of message interpretation.
1526 When sending messages all their parts and attachments are classified.
1527 Whereas no character set conversion is performed on those parts which
1528 appear to be binary data,
1529 the character set being used must be declared within the MIME header of
1530 an outgoing text part if it contains characters that do not conform to
1531 the set of characters that are allowed by the email standards.
1532 Permissible values for character sets can be declared using the
1536 which defines a catch-all last-resort fallback character set that is
1537 implicitly appended to the list of character-sets in
1541 When replying to a message and the variable
1542 .Va reply-in-same-charset
1543 is set then the character set of the message being replied to is tried
1545 And it is also possible to make \*(UA work even more closely related to
1546 the current locale setting automatically by using the variable
1547 .Va sendcharsets-else-ttycharset ,
1548 please see there for more information.
1551 All the specified character sets are tried in order unless the
1552 conversion of the part or attachment succeeds.
1553 If none of the tried (8-bit) character sets is capable to represent the
1554 content of the part or attachment,
1555 then the message will not be sent and its text will optionally be
1559 In general, if the message
1560 .Dq Cannot convert from a to b
1561 appears, either some characters are not appropriate for the currently
1562 selected (terminal) character set,
1563 or the needed conversion is not supported by the system.
1564 In the first case, it is necessary to set an appropriate
1566 locale and/or the variable
1570 The best results are usually achieved when \*(UA is run in a UTF-8
1571 locale on a UTF-8 capable terminal, in which case the full Unicode
1572 spectrum of characters is available.
1573 In this setup characters from various countries can be displayed,
1574 while it is still possible to use more simple character sets for sending
1575 to retain maximum compatibility with older mail clients.
1578 On the other hand the POSIX standard defines a locale-independent 7-bit
1579 .Dq portable character set
1580 that should be used when overall portability is an issue, the even more
1581 restricted subset named
1582 .Dq portable filename character set
1583 consisting of A-Z, a-z, 0-9, period
1592 .\" .Ss "Message states" {{{
1593 .Ss "Message states"
1595 \*(UA differentiates in between several different message states;
1596 the current state will be reflected in header summary displays if
1598 is configured to do so (via the internal variable
1600 and messages can also be selected and be acted upon depending on their
1602 .Sx "Specifying messages" ) .
1603 When operating on the system
1605 or in primary mailboxes opened with the special prefix
1609 special actions, like the automatic moving of messages to the secondary
1611 mailbox may be applied when the mailbox is left (also implicitly via
1612 a successful exit of \*(UA, but not if the special command
1614 is used) \(en however, because this may be irritating to users which
1617 mail-user-agents, the default global
1623 variables in order to suppress this behaviour.
1625 .Bl -tag -width ".It Ql _reserved"
1627 Message has neither been viewed nor moved to any other state.
1628 Such messages are retained even in the primary system mailbox.
1631 Message has neither been viewed nor moved to any other state, but the
1632 message was present already when the mailbox has been opened last:
1633 Such messages are retained even in the primary system mailbox.
1636 The message has been processed by one of the following commands:
1656 commands may also cause the next message to be marked as read, depending
1662 command is used, messages that are in the primary system mailbox or in
1663 mailboxes which were opened with the special
1667 state when the mailbox is left will be saved in
1669 unless the internal variable
1674 The message has been processed by one of the following commands:
1680 can be used to access such messages.
1683 The message has been processed by a
1685 command and it will be retained in its current location.
1688 The message has been processed by one of the following commands:
1694 command is used, messages that are in the primary system mailbox or in
1695 mailboxes which were opened with the special
1699 state when the mailbox is left will be deleted; they will be saved in
1701 when the internal variable
1707 .\" .Ss "Specifying messages" {{{
1708 .Ss "Specifying messages"
1715 can be given a list of message numbers as arguments to apply to a number
1716 of messages at once.
1719 deletes messages 1 and 2,
1722 will delete the messages 1 through 5.
1723 In sorted or threaded mode (see the
1727 will delete the messages that are located between (and including)
1728 messages 1 through 5 in the sorted/threaded order, as shown in the
1731 The following special message names exist:
1734 .Bl -tag -width ".It Ar _n_u"
1736 The current message, the so-called
1740 The message that was previously the current message.
1743 The parent message of the current message,
1744 that is the message with the Message-ID given in the
1746 field or the last entry of the
1748 field of the current message.
1751 The next previous undeleted message,
1752 or the next previous deleted message for the
1755 In sorted/threaded mode,
1756 the next previous such message in the sorted/threaded order.
1759 The next undeleted message,
1760 or the next deleted message for the
1763 In sorted/threaded mode,
1764 the next such message in the sorted/threaded order.
1767 The first undeleted message,
1768 or the first deleted message for the
1771 In sorted/threaded mode,
1772 the first such message in the sorted/threaded order.
1776 In sorted/threaded mode,
1777 the last message in the sorted/threaded order.
1781 selects the message addressed with
1785 is any other message specification,
1786 and all messages from the thread that begins at it.
1787 Otherwise it is identical to
1792 the thread beginning with the current message is selected.
1797 All messages that were included in the message list for the previous
1801 An inclusive range of message numbers.
1802 Selectors that may also be used as endpoints include any of
1807 .Dq any substring matches
1810 header, which will match addresses (too) even if
1812 is set (and POSIX says
1813 .Dq any address as shown in a header summary shall be matchable in this form ) ;
1816 variable is set, only the local part of the address is evaluated
1817 for the comparison, not ignoring case, and the setting of
1819 is completely ignored.
1820 For finer control and match boundaries use the
1824 .It Ar / Ns Ar string
1825 All messages that contain
1827 in the subject field (case ignored).
1834 the string from the previous specification of that type is used again.
1836 .It Xo Op Ar @ Ns Ar name-list Ns
1839 All messages that contain the given case-insensitive search
1841 ession; if the \*(OPal regular expression (see
1843 support is available
1845 will be interpreted as (an extended) one if any of the
1847 (extended) regular expression characters is seen.
1849 .Ar @ Ns Ar name-list
1850 part is missing, the search is restricted to the subject field body,
1853 specifies a comma-separated list of header fields to search, as in
1855 .Dl '@to,from,cc@Someone i ought to know'
1857 In order to search for a string that includes a
1859 (commercial at) character the
1861 is effectively non-optional, but may be given as the empty string.
1862 Some special header fields may be abbreviated:
1876 respectively and case-insensitively.
1881 can be used to search in (all of) the header(s) of the message, and the
1890 can be used to perform full text searches \(en whereas the former
1891 searches only the body, the latter also searches the message header.
1893 This message specification performs full text comparison, but even with
1894 regular expression support it is almost impossible to write a search
1895 expression that savely matches only a specific address domain.
1896 To request that the content of the header is treated as a list of
1897 addresses, and to strip those down to the plain email address which the
1898 search expression is to be matched against, prefix the header name
1899 (abbreviation) with a tilde
1902 .Dl @~f@@a\e.safe\e.domain\e.match$
1905 All messages of state
1909 is one or multiple of the following colon modifiers:
1911 .Bl -tag -compact -width ".It Ar :M"
1916 Old messages (any not in state
1942 Messages marked as draft.
1944 \*(OP Messages classified as spam.
1946 \*(OP Messages with unsure spam classification.
1952 \*(OP IMAP-style SEARCH expressions may also be used.
1953 This addressing mode is available with all types of folders;
1954 \*(UA will perform the search locally as necessary.
1955 Strings must be enclosed by double quotes
1957 in their entirety if they contain white space or parentheses;
1958 within the quotes, only reverse solidus
1960 is recognized as an escape character.
1961 All string searches are case-insensitive.
1962 When the description indicates that the
1964 representation of an address field is used,
1965 this means that the search string is checked against both a list
1968 .Bd -literal -offset indent
1969 (\*qname\*q \*qsource\*q \*qlocal-part\*q \*qdomain-part\*q)
1974 and the addresses without real names from the respective header field.
1975 These search expressions can be nested using parentheses, see below for
1979 .Bl -tag -compact -width ".It Ar _n_u"
1980 .It Ar ( criterion )
1981 All messages that satisfy the given
1983 .It Ar ( criterion1 criterion2 ... criterionN )
1984 All messages that satisfy all of the given criteria.
1986 .It Ar ( or criterion1 criterion2 )
1987 All messages that satisfy either
1992 To connect more than two criteria using
1994 specifications have to be nested using additional parentheses,
1996 .Ql (or a (or b c)) ,
2000 .Ql ((a or b) and c) .
2003 operation of independent criteria on the lowest nesting level,
2004 it is possible to achieve similar effects by using three separate
2008 .It Ar ( not criterion )
2009 All messages that do not satisfy
2011 .It Ar ( bcc \*q Ns Ar string Ns Ar \*q )
2012 All messages that contain
2014 in the envelope representation of the
2017 .It Ar ( cc \*q Ns Ar string Ns Ar \*q )
2018 All messages that contain
2020 in the envelope representation of the
2023 .It Ar ( from \*q Ns Ar string Ns Ar \*q )
2024 All messages that contain
2026 in the envelope representation of the
2029 .It Ar ( subject \*q Ns Ar string Ns Ar \*q )
2030 All messages that contain
2035 .It Ar ( to \*q Ns Ar string Ns Ar \*q )
2036 All messages that contain
2038 in the envelope representation of the
2041 .It Ar ( header name \*q Ns Ar string Ns Ar \*q )
2042 All messages that contain
2047 .It Ar ( body \*q Ns Ar string Ns Ar \*q )
2048 All messages that contain
2051 .It Ar ( text \*q Ns Ar string Ns Ar \*q )
2052 All messages that contain
2054 in their header or body.
2055 .It Ar ( larger size )
2056 All messages that are larger than
2059 .It Ar ( smaller size )
2060 All messages that are smaller than
2064 .It Ar ( before date )
2065 All messages that were received before
2067 which must be in the form
2071 denotes the day of the month as one or two digits,
2073 is the name of the month \(en one of
2074 .Ql Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ,
2077 is the year as four digits, e.g.,
2081 All messages that were received on the specified date.
2082 .It Ar ( since date )
2083 All messages that were received since the specified date.
2084 .It Ar ( sentbefore date )
2085 All messages that were sent on the specified date.
2086 .It Ar ( senton date )
2087 All messages that were sent on the specified date.
2088 .It Ar ( sentsince date )
2089 All messages that were sent since the specified date.
2091 The same criterion as for the previous search.
2092 This specification cannot be used as part of another criterion.
2093 If the previous command line contained more than one independent
2094 criterion then the last of those criteria is used.
2098 .\" .Ss "On URL syntax and credential lookup" {{{
2099 .Ss "On URL syntax and credential lookup"
2101 \*(IN For accessing protocol-specific resources usage of Uniform
2102 Resource Locators (URL, RFC 1738) has become omnipresent.
2103 \*(UA expects and understands URLs in the following form;
2106 denote optional parts, optional either because there also exist other
2107 ways to define the information in question or because support of the
2108 part is protocol-specific (e.g.,
2110 is used by the IMAP protocol but not by POP3);
2115 are specified they must be given in URL percent encoded form (RFC 3986;
2121 .Dl PROTOCOL://[USER[:PASSWORD]@]server[:port][/path]
2124 Note that these \*(UA URLs most often do not conform to any real
2125 standard, but instead represent a normalized variant of RFC 1738 \(en
2126 they are not used in data exchange but only meant as a compact,
2127 easy-to-use way of defining and representing information in
2128 a well-known notation.
2131 Many internal variables of \*(UA exist in multiple versions, called
2132 variable chains for the rest of this document: the plain
2137 .Ql variable-USER@HOST .
2144 had been specified in the respective URL, otherwise it refers to the plain
2150 that had been found when doing the user chain lookup as is described
2153 will never be in URL percent encoded form, whether it came from an URL
2154 or not; i.e., variable chain name extensions of
2155 .Sx "INTERNAL VARIABLES"
2156 must not be URL percent encoded.
2159 For example, whether an hypothetical URL
2160 .Ql smtp://hey%3Ayou@our.house
2161 had been given that includes a user, or whether the URL was
2162 .Ql smtp://our.house
2163 and the user had been found differently, to lookup the variable chain
2164 .Va smtp-use-starttls
2165 \*(UA first looks for whether
2166 .Ql smtp-\:use-\:starttls-\:hey:you@our.house
2167 is defined, then whether
2168 .Ql smtp-\:use-\:starttls-\:our.house
2169 exists before finally ending up looking at the plain variable itself.
2172 \*(UA obeys the following logic scheme when dealing with the
2173 necessary credential information of an account:
2179 has been given in the URL the variables
2183 are looked up; if no such variable(s) can be found then \*(UA will,
2184 when enforced by the \*(OPal variables
2185 .Va netrc-lookup-HOST
2192 specific entry which provides a
2194 name: this lookup will only succeed if unambiguous (one possible matching
2197 It is possible to load encrypted
2202 If there is still no
2204 then \*(UA will fall back to the user who is supposed to run \*(UA,
2205 the identity of which has been fixated during \*(UA startup and is
2206 known to be a valid user on the current host.
2209 Authentication: unless otherwise noted this will lookup the
2210 .Va PROTOCOL-auth-USER@HOST , PROTOCOL-auth-HOST , PROTOCOL-auth
2211 variable chain, falling back to a protocol-specific default should this
2217 has been given in the URL, then if the
2219 has been found through the \*(OPal
2221 that may have already provided the password, too.
2222 Otherwise the variable chain
2223 .Va password-USER@HOST , password-HOST , password
2224 is looked up and used if existent.
2226 Afterwards the complete \*(OPal variable chain
2227 .Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup
2231 cache is searched for a password only (multiple user accounts for
2232 a single machine may exist as well as a fallback entry without user
2233 but with a password).
2235 If at that point there is still no password available, but the
2236 (protocols') chosen authentication type requires a password, then in
2237 interactive mode the user will be prompted on the terminal.
2242 S/MIME verification works relative to the values found in the
2246 header field(s), which means that the values of
2247 .Va smime-sign , smime-sign-cert , smime-sign-include-certs
2249 .Va smime-sign-message-digest
2250 will not be looked up using the
2254 chains from above but instead use the corresponding values from the
2255 message that is being worked on.
2256 In unusual cases multiple and different
2260 combinations may therefore be involved \(en on the other hand those
2261 unusual cases become possible.
2262 The usual case is as short as:
2265 .Dl set mta=smtp://USER:PASS@HOST smtp-use-starttls \e
2266 .Dl \ \ \ \ smime-sign smime-sign-cert=+smime.pair
2271 contains complete example configurations.
2274 .\" .Ss "On terminal control and line editor" {{{
2275 .Ss "On terminal control and line editor"
2277 \*(OP Terminal control will be realized through one of the standard
2279 libraries, either the
2281 or, alternatively, the
2283 both of which will be initialized to work with the environment variable
2285 Terminal control will enhance or enable interactive usage aspects, e.g.,
2286 .Sx "Coloured display" ,
2287 and extend behaviour of the Mailx-Line-Editor (MLE), which may learn the
2288 byte-sequences of keys like the cursor and function keys, and which will
2289 automatically enter the so-called
2291 alternative screen shall the terminal support it.
2292 The internal variable
2294 can be used to overwrite settings or to learn (correct(ed)) keycodes.
2295 Actual interaction with the chosen library can be disabled completely by
2296 setting the internal variable
2297 .Va termcap-disable ;
2299 will be queried regardless, even if the \*(OPal support for the
2300 libraries has not been enabled at configuration time.
2303 \*(OP The builtin \*(UA Mailx-Line-Editor (MLE) should work in all
2304 environments which comply to the ISO C standard
2306 and will support wide glyphs if possible (the necessary functionality
2307 had been removed from ISO C, but was included in
2309 Prevent usage of a line editor in interactive mode by setting the
2311 .Va line-editor-disable .
2312 Especially if the \*(OPal terminal control support is missing setting
2313 entries in the internal variable
2315 will help shall the MLE misbehave, see there for more.
2316 The MLE can support a little bit of
2322 feature is available then input from line editor prompts will be saved
2323 in a history list that can be searched in and be expanded from.
2324 Such saving can be prevented by prefixing input with any amount of
2326 Aspects of history, like allowed content and maximum size, as well as
2327 whether history shall be saved persistently, can be configured with the
2331 .Va history-gabby-persist
2336 The MLE supports a set of editing and control commands.
2337 By default (as) many (as possible) of these will be assigned to a set of
2338 single-letter control codes, which should work on any terminal (and can
2339 be generated by holding the
2341 key while pressing the key of desire, e.g.,
2345 command is available then the MLE commands can also be accessed freely
2346 by assigning the command name, which is shown in parenthesis in the list
2347 below, to any desired key-sequence, and the MLE will instead and also use
2349 to establish its builtin key bindings
2350 (more of them if the \*(OPal terminal control is available),
2351 an action which can then be suppressed completely by setting
2352 .Va line-editor-no-defaults .
2353 The following uses the
2355 ell-style quote notation that is documented in the introduction of
2357 combinations not mentioned either cause job control signals or do not
2358 generate a (unique) keycode:
2362 .Bl -tag -compact -width "Ql _M"
2364 Go to the start of the line
2365 .Pf ( Cd mle-go-home ) .
2368 Move the cursor backward one character
2369 .Pf ( Cd mle-go-bwd ) .
2372 Forward delete the character under the cursor;
2373 quits \*(UA if used on the empty line unless the internal variable
2376 .Pf ( Cd mle-del-fwd ) .
2379 Go to the end of the line
2380 .Pf ( Cd mle-go-end ) .
2383 Move the cursor forward one character
2384 .Pf ( Cd mle-go-fwd ) .
2387 Cancel current operation, full reset.
2388 If there is an active history search or tabulator expansion then this
2389 command will first reset that, reverting to the former line content;
2390 thus a second reset is needed for a full reset in this case
2391 .Pf ( Cd mle-reset ) .
2394 Backspace: backward delete one character
2395 .Pf ( Cd mle-del-bwd ) .
2399 Horizontal tabulator:
2400 try to expand the word before the cursor, also supporting \*(UA
2403 .Pf ( Cd mle-complete ) .
2405 .Cd mle-quote-rndtrip .
2409 commit the current line
2410 .Pf ( Cd mle-commit ) .
2413 Cut all characters from the cursor to the end of the line
2414 .Pf ( Cd mle-snarf-end ) .
2418 .Pf ( Cd mle-repaint ) .
2421 \*(OP Go to the next history entry
2422 .Pf ( Cd mle-hist-fwd ) .
2425 (\*(OPally context-dependent) Invokes the command
2429 \*(OP Go to the previous history entry
2430 .Pf ( Cd mle-hist-bwd ) .
2433 Toggle roundtrip mode shell quotes, where produced,
2435 .Pf ( Cd mle-quote-rndtrip ) .
2436 This setting is temporary, and will be forgotten once the command line
2440 \*(OP Complete the current line from (the remaining) older history entries
2441 .Pf ( Cd mle-hist-srch-bwd ) .
2444 \*(OP Complete the current line from (the remaining) newer history entries
2445 .Pf ( Cd mle-hist-srch-fwd ) .
2448 Paste the snarf buffer
2449 .Pf ( Cd mle-paste ) .
2456 .Pf ( Cd mle-snarf-line ) .
2459 Prompts for a Unicode character (its hexadecimal number) to be inserted
2460 .Pf ( Cd mle-prompt-char ) .
2461 Note this command needs to be assigned to a single-letter control code
2462 in order to become recognized and executed during input of
2463 a key-sequence (only three single-letter control codes can be used for
2464 that shortcut purpose); this control code is special-treated and cannot
2465 be part of any other sequence, because any occurrence will perform the
2467 function immediately.
2470 Cut the characters from the one preceding the cursor to the preceding
2472 .Pf ( Cd mle-snarf-word-bwd ) .
2475 Move the cursor forward one word boundary
2476 .Pf ( Cd mle-go-word-fwd ) .
2479 Move the cursor backward one word boundary
2480 .Pf ( Cd mle-go-word-bwd ) .
2483 Escape: reset a possibly used multibyte character input state machine
2484 and \*(OPally a lingering, incomplete key binding
2485 .Pf ( Cd mle-cancel ) .
2486 This command needs to be assigned to a single-letter control code in
2487 order to become recognized and executed during input of a key-sequence
2488 (only three single-letter control codes can be used for that shortcut
2490 This control code may also be part of a multi-byte sequence, but if
2491 a sequence is active and the very control code is currently also an
2492 expected input, then it will first be consumed by the active sequence.
2495 (\*(OPally context-dependent) Invokes the command
2499 (\*(OPally context-dependent) Invokes the command
2503 (\*(OPally context-dependent) Invokes the command
2507 Cut the characters from the one after the cursor to the succeeding word
2509 .Pf ( Cd mle-snarf-word-fwd ) .
2519 this will immediately reset a possibly active search etc.
2523 ring the audible bell.
2527 .\" .Ss "Coloured display" {{{
2528 .Ss "Coloured display"
2530 \*(OP \*(UA can be configured to support a coloured display and font
2531 attributes by emitting ANSI / ISO 6429 SGR (select graphic rendition)
2533 Usage of colours and font attributes solely depends upon the
2534 capability of the detected terminal type that is defined by the
2535 environment variable
2537 and which can be fine-tuned by the user via the internal variable
2541 On top of what \*(UA knows about the terminal the boolean variable
2543 defines whether the actually applicable colour and font attribute
2544 sequences should also be generated when output is going to be paged
2545 through the external program defined by the environment variable
2550 This is not enabled by default because different pager programs need
2551 different command line switches or other configuration in order to
2552 support those sequences.
2553 \*(UA however knows about some widely used pagers and in a clean
2554 environment it is often enough to simply set
2556 please refer to that variable for more on this topic.
2561 is set then any active usage of colour and font attribute sequences
2562 is suppressed, but without affecting possibly established
2567 To define and control colours and font attributes a single multiplexer
2568 command family exists:
2570 shows or defines colour mappings for the given colour type (e.g.,
2573 can be used to remove mappings of a given colour type.
2574 Since colours are only available in interactive mode, it may make
2575 sense to conditionalize the colour setup by encapsulating it with
2578 .Bd -literal -offset indent
2579 if terminal && $features =@ +colour
2580 colour iso view-msginfo ft=bold,fg=green
2581 colour iso view-header ft=bold,fg=red "from,subject"
2582 colour iso view-header fg=red
2584 uncolour iso view-header from,subject
2585 colour iso view-header ft=bold,fg=magenta,bg=cyan
2586 colour 256 view-header ft=bold,fg=208,bg=230 subject,from
2587 colour mono view-header ft=bold
2588 colour mono view-header ft=bold,ft=reverse subject,from
2592 .\" }}} (DESCRIPTION)
2595 .\" .Sh COMMANDS {{{
2598 Each command is typed on a line by itself,
2599 and may take arguments following the command word.
2600 Command names may be abbreviated, in which case the first command that
2601 matches the given prefix will be used.
2604 can be used to show the list of all commands, either alphabetically
2605 sorted or in prefix search order (these do not match, also because the
2606 POSIX standard prescribes a set of abbreviations).
2607 \*(OPally the command
2611 when given an argument, will show a documentation string for the
2612 command matching the expanded argument, as in
2614 which should be a shorthand of
2616 Both commands support a more
2618 listing mode which includes the argument type of the command.
2621 For commands which take message lists as arguments, the next message
2622 forward that satisfies the command's requirements will be used shall no
2623 explicit message list have been specified.
2624 If there are no messages forward of the current message,
2625 the search proceeds backwards,
2626 and if there are no good messages at all,
2627 \*(UA shows an error message and aborts the command.
2628 \*(ID Non-message-list arguments can be quoted using the following methods:
2631 .Bl -bullet -compact -offset indent
2633 An argument can be enclosed between paired double-quotes
2638 any white space, shell word expansion, or reverse solidus characters
2639 (except as described next) within the quotes are treated literally as
2640 part of the argument.
2641 A double-quote will be treated literally within single-quotes and vice
2643 Inside such a quoted string the actually used quote character can be
2644 used nonetheless by escaping it with a reverse solidus
2650 An argument that is not enclosed in quotes, as above, can usually still
2651 contain space characters if those spaces are reverse solidus escaped, as in
2655 A reverse solidus outside of the enclosing quotes is discarded
2656 and the following character is treated literally as part of the argument.
2661 Some commands which do not take message-list arguments can also be
2662 prefixed with the special keyword
2664 to choose \*(INible argument quoting rules, and some new commands only
2665 support the new rules (without that keyword) and are flagged \*(NQ.
2666 In the future \*(UA will (mostly) use
2668 compatible argument parsing:
2669 Non-message-list arguments can be quoted using the following shell-style
2670 mechanisms: the escape character, single-quotes, double-quotes and
2671 dollar-single-quotes; any unquoted number sign
2673 that parses as a new token starts a comment that ends argument processing.
2674 The overall granularity of error reporting and diagnostics, also
2675 regarding function arguments and their content, will improve.
2679 .Bl -bullet -compact -offset indent
2681 The literal value of any character can be preserved by preceding it
2682 with the escape character reverse solidus
2686 will cause variable expansion of the given name: \*(UA
2687 .Sx "INTERNAL VARIABLES"
2690 (shell) variables can be accessed through this mechanism, brace
2691 enclosing the name is supported.
2694 Arguments which are enclosed in
2695 .Ql 'single-\:quotes'
2696 retain their literal value.
2697 A single-quote cannot occur within single-quotes.
2700 The literal value of all characters enclosed in
2701 .Ql \(dqdouble-\:quotes\(dq
2702 is retained, with the exception of dollar
2704 which will cause variable expansion, as above, backquote (grave accent)
2706 (which not yet means anything special), reverse solidus
2708 which will escape any of the characters dollar
2710 (to prevent variable expansion), backquote (grave accent)
2714 (to prevent ending the quote) and reverse solidus
2716 (to prevent escaping, i.e., to embed a reverse solidus character as-is),
2717 but has no special meaning otherwise.
2720 Arguments enclosed in
2721 .Ql $'dollar-\:single-\:quotes'
2722 extend normal single quotes in that reverse solidus escape sequences are
2723 expanded as follows:
2725 .Bl -tag -compact -width "Ql \eNNN"
2731 an escape character.
2733 an escape character.
2745 emits a reverse solidus character.
2749 double quote (escaping is optional).
2751 eight-bit byte with the octal value
2753 (one to three octal digits), optionally prefixed by an additional
2755 A 0 byte will suppress further output for the quoted argument.
2757 eight-bit byte with the hexadecimal value
2759 (one or two hexadecimal characters).
2760 A 0 byte will suppress further output for the quoted argument.
2762 the Unicode / ISO-10646 character with the hexadecimal codepoint value
2764 (one to eight hexadecimal digits) \(em note that Unicode defines the
2765 maximum codepoint to be ever supported as
2770 This escape is only supported in locales which support Unicode (see
2771 .Sx "Character sets" ) ,
2772 in other cases the sequence will remain unexpanded unless the given code
2773 point is ASCII compatible or can be represented in the current locale.
2774 The character NUL will suppress further output for the quoted argument.
2778 except it takes only one to four hexadecimal digits.
2780 A mechanism that allows usage of the non-printable (ASCII and
2781 compatible) control codes 0 to 31: to create the printable
2782 representation of a control code the numeric value 64 is added, and the
2783 resulting ASCII character set code point is then printed, e.g., BEL is
2784 .Ql 7 + 64 = 71 = G .
2785 Whereas historically circumflex notation has often been used for
2786 visualization purposes of control codes, e.g.,
2788 the reverse solidus notation has been standardized:
2790 Some control codes also have standardized (ISO 10646, ISO C) alias
2791 representations, as shown above (e.g.,
2795 whenever such an alias exists \*(UA will use it for display purposes.
2796 The control code NUL
2798 ends argument processing without producing further output.
2800 Non-standard extension: expand the given variable name, as above.
2801 Brace enclosing the name is supported.
2803 Not yet supported, just to raise awareness: Non-standard extension.
2809 .Sy Compatibility notes:
2810 \*(ID Note these are new mechanisms which are not supported by all
2812 Round-tripping (feeding in things shown in list modes again) are not yet
2813 stable or possible at all.
2814 On new-style command lines it is wise to quote semicolon
2818 characters in order to ensure upward compatibility: the author would
2819 like to see things like
2820 .Ql ? echo $'trouble\etahead' | cat >> in_the_shell.txt
2822 .Ql ? top 2 5 10; type 3 22
2824 Before \*(UA will switch entirely to shell-style argument parsing there
2825 will be a transition phase where using
2827 will emit obsoletion warnings.
2829 .Bd -literal -offset indent
2830 echo 'Quotes '${HOME}' and 'tokens" differ!"# no comment
2831 echo Quotes ${HOME} and tokens differ! # comment
2832 echo Don"'"t you worry$'\ex21' The sun shines on us. $'\eu263A'
2836 In any event an unquoted reverse solidus at the end of a command line is
2837 discarded and the next line continues the command.
2838 \*(ID Note that line continuation is handled before the above parsing is
2839 applied, i.e., the parsers documented above will see merged lines.
2840 Filenames, where expected, are subsequently subjected to the following
2841 transformations, in sequence:
2844 .Bl -bullet -compact -offset indent
2846 If the filename begins with an unquoted plus sign, and the
2848 variable is defined,
2849 the plus sign will be replaced by the value of the
2851 variable followed by a solidus.
2854 variable is unset or is set to null, the filename will be unchanged.
2857 Meta expansions are applied to the filename: a leading tilde
2859 character will be replaced by the expansion of
2861 except when followed by a valid user name, in which case the home
2862 directory of the given user is used instead.
2867 will be replaced by the expansion of the variable, if possible; \*(UA
2868 .Sx "INTERNAL VARIABLES"
2871 (shell) variables can be accessed through this mechanism, and the usual
2872 escape mechanism has to be applied to prevent interpretation.
2873 If the fully expanded filename results in multiple pathnames and the
2874 command is expecting only one file, an error results.
2876 In interactive context, in order to allow simple value acceptance (via
2878 arguments will usually be displayed in a properly quoted form, e.g., a file
2879 .Ql diet\e is \ecurd.txt
2881 .Ql 'diet\e is \ecurd.txt' .
2885 The following commands are available:
2887 .Bl -tag -width ".Ic _ccount"
2892 command which follows, replacing unescaped exclamation marks with the
2893 previously executed command if the internal variable
2899 The comment-command causes the entire line to be ignored.
2901 this really is a normal command which' purpose is to discard its
2904 indicating special character, which means that, e.g., trailing comments
2905 on a line are not possible.
2909 Goes to the next message in sequence and types it
2915 Display the preceding message, or the n'th previous message if given
2916 a numeric argument n.
2920 Show the current message number (the
2925 Show a brief summary of commands.
2928 output is available.
2929 \*(OP Given an argument a synopsis for the command in question is
2930 shown instead; commands can be abbreviated in general and this command
2931 can be used to see the full expansion of an abbreviation including the
2932 synopsis, try, e.g.,
2937 and see how the output changes.
2947 Interprets the remainder of the word as a macro name and passes it
2952 is a shorter synonym for
2953 .Ql call Ar mymacro .
2957 (ac) Creates, selects or lists (an) account(s).
2958 Accounts are special incarnations of
2960 macros and group commands and variable settings which together usually
2961 arrange the environment for the purpose of creating an email account.
2962 Different to normal macros settings which are covered by
2964 \(en here by default enabled! \(en will not be reverted before the
2969 (case-insensitive) always exists, and all but it can be deleted via
2972 Without arguments a listing of all defined accounts is shown.
2973 With one argument the given account is activated: the system
2975 of that account will be activated (as via
2977 and a possibly installed
2980 The two argument form is identical to defining a macro as via
2982 .Bd -literal -offset indent
2984 set folder=~/mail inbox=+syste.mbox record=+sent.mbox
2985 set from='myname@myisp.example (My Name)'
2986 set mta=smtp://mylogin@smtp.myisp.example
2992 (a) With no arguments, shows all currently-defined aliases.
2993 With one argument, shows that alias.
2994 With more than one argument,
2995 creates a new alias or appends to an existing one.
2997 can be used to delete aliases.
3001 (alt) Manage a list of alternate addresses / names of the active user,
3002 members of which will be removed from recipient lists when replying to
3005 variable is not set).
3006 If arguments are given the set of alternate names is replaced by them,
3007 without arguments the current set is displayed.
3011 Takes a message list and marks each message as having been answered.
3012 This mark has no technical meaning in the mail system;
3013 it just causes messages to be marked in the header summary,
3014 and makes them specially addressable.
3019 \*(OP\*(NQ The bind command extends the MLE (see
3020 .Sx "On terminal control and line editor" )
3021 with freely configurable key bindings.
3022 With one argument all bindings for the given context are shown,
3023 specifying an asterisk
3025 will show the bindings of all contexts; a more verbose listing will be
3026 produced if either of
3031 With two or more arguments a binding is (re)established:
3032 the first argument is the context to which the binding shall apply,
3033 the second argument is a comma-separated list of the
3035 which form the binding, and any remaining arguments form the expansion.
3036 To indicate that a binding shall not be auto-committed, but that the
3037 expansion shall instead be furtherly editable by the user, an at-sign
3039 (that will be removed) can be placed last in the expansion, from which
3040 leading and trailing whitespace will finally be removed.
3041 Reverse solidus cannot be used as the last character of expansion.
3044 Contexts define when a binding applies, i.e., a binding will not be seen
3045 unless the context for which it is defined for is currently active.
3046 This is not true for the shared binding
3048 which is the foundation for all other bindings and as such always
3049 applies, its bindings, however, only apply secondarily.
3050 The available contexts are the shared
3054 context which is used in all not otherwise documented situations, and
3056 which applies to compose mode only.
3060 which form the binding are specified as a comma-separated list of
3061 byte-sequences, where each list entry corresponds to one key(press).
3062 \*(OPally a list entry may, indicated by a leading colon character
3064 also refer to the name of a terminal capability;
3065 several dozen names will be compiled into \*(UA and may be specified
3068 or, if existing, by their
3070 name, regardless of the actually used terminal control library.
3071 It is however possible to use any capability, as long as the name is
3072 resolvable by the control library or defined in the internal variable
3074 Input sequences are not case-normalized, so that an exact match is
3075 required to update or remove a binding.
3078 .Bd -literal -offset indent
3079 bind base $'\eE',d mle-snarf-word-fwd # Esc(ape)
3080 bind base $'\eE',$'\ec?' mle-snarf-word-bwd # Esc, Delete
3081 bind default $'\ecA',:khome,w 'echo An editable binding@'
3082 bind default a,b,c rm -rf / @ # Another editable binding
3083 bind default :kf1 File %
3084 bind compose :kf1 ~e
3088 Note that the entire comma-separated list is first parsed (over) as a
3089 shell-token with whitespace as the field separator, before being parsed
3090 and expanded for real with comma as the field separator, therefore
3091 whitespace needs to be properly quoted:
3092 shell-style quoting is documented in the introduction of
3094 Using Unicode reverse solidus escape sequences renders a binding
3095 defunctional if the locale does not support Unicode (see
3096 .Sx "Character sets" ) ,
3097 and using terminal capabilities does so if no terminal control support
3098 is (currently) available.
3101 The following terminal capability names are builtin and can be used in
3103 or (if available) the two-letter
3105 notation regardless of the actually used library.
3106 See the respective manual for a list of capabilities.
3109 can be used to show all the capabilities of
3111 or the given terminal type;
3114 flag will also show supported (non-standard) extensions.
3117 .Bl -tag -compact -width kcuuf_or_kcuuf
3118 .It Cd kbs Ns \0or Cd kb
3120 .It Cd kdch1 Ns \0or Cd kD
3122 .It Cd kDC Ns \0or Cd *4
3123 \(em shifted variant.
3124 .It Cd kel Ns \0or Cd kE
3125 Clear to end of line.
3126 .It Cd kext Ns \0or Cd @9
3128 .It Cd kich1 Ns \0or Cd kI
3130 .It Cd kIC Ns \0or Cd #3
3131 \(em shifted variant.
3132 .It Cd khome Ns \0or Cd kh
3134 .It Cd kHOM Ns \0or Cd #2
3135 \(em shifted variant.
3136 .It Cd kend Ns \0or Cd @7
3138 .It Cd knp Ns \0or Cd kN
3140 .It Cd kpp Ns \0or Cd kP
3142 .It Cd kcub1 Ns \0or Cd kl
3143 Left cursor (with more modifiers: see below).
3144 .It Cd kLFT Ns \0or Cd #4
3145 \(em shifted variant.
3146 .It Cd kcuf1 Ns \0or Cd kr
3147 Right cursor (ditto).
3148 .It Cd kRIT Ns \0or Cd %i
3149 \(em shifted variant.
3150 .It Cd kcud1 Ns \0or Cd kd
3151 Down cursor (ditto).
3153 \(em shifted variant (only terminfo).
3154 .It Cd kcuu1 Ns \0or Cd ku
3157 \(em shifted variant (only terminfo).
3158 .It Cd kf0 Ns \0or Cd k0
3160 Add one for each function key up to
3165 .It Cd kf10 Ns \0or Cd k;
3167 .It Cd kf11 Ns \0or Cd F1
3169 Add one for each function key up to
3177 Some terminals support key-modifier combination extensions, e.g.,
3179 For example, the delete key,
3181 in its shifted variant, the name is mutated to
3183 then a number is appended for the states
3195 .Ql Shift+Alt+Control
3197 The same for the left cursor key,
3199 .Cd KLFT , KLFT3 , KLFT4 , KLFT5 , KLFT6 , KLFT7 , KLFT8 .
3202 Key bindings can be removed with the command
3204 It is advisable to use an initial escape or other control character (e.g.,
3206 for bindings which describe user key combinations (as opposed to purely
3207 terminal capability based ones), in order to avoid ambiguities whether
3208 input belongs to key sequences or not; it also reduces search time.
3211 may help shall keys and sequences be falsely recognized.
3216 Calls a macro that has been created via
3221 (ch) Change the working directory to
3223 or the given argument.
3229 \*(OP Only applicable to S/MIME signed messages.
3230 Takes a message list and a file name and saves the certificates
3231 contained within the message signatures to the named file in both
3232 human-readable and PEM format.
3233 The certificates can later be used to send encrypted messages to the
3234 respective message senders by setting
3235 .Va smime-encrypt-USER@HOST
3240 (ch) Change the working directory to
3242 or the given argument.
3248 Only applicable to threaded mode.
3249 Takes a message list and makes all replies to these messages invisible
3250 in header summaries, unless they are in state
3256 \*(OP\*(NQ Manage colour mappings of and for a
3257 .Sx "Coloured display" .
3258 The type of colour is given as the (case-insensitive) first argument,
3259 which must be one of
3261 for 256-colour terminals,
3266 for the standard 8-colour ANSI / ISO 6429 color palette and
3270 for monochrome terminals.
3271 Monochrome terminals cannot deal with colours, but only (some) font
3275 Without further arguments the list of all currently defined mappings
3276 for the given colour type is shown (as a special case giving
3280 will show the mappings of all types).
3281 Otherwise the second argument defines the mappable slot, and the third
3282 argument a (comma-separated list of) colour and font attribute
3283 specification(s), and the optional fourth argument can be used to
3284 specify a precondition: if conditioned mappings exist they are tested in
3285 (creation) order unless a (case-insensitive) match has been found, and
3286 the default mapping (if any has been established) will only be chosen as
3288 The types of precondition available depend on the mappable slot (see
3289 .Sx "Coloured display"
3290 for some examples), the following of which exist:
3293 Mappings prefixed with
3295 are used for the \*(OPal builtin Mailx-Line-Editor (MLE, see
3296 .Sx "On terminal control and line editor" )
3297 and do not support preconditions.
3299 .Bl -tag -compact -width view-partinfo
3301 This mapping is used for the position indicator that is visible when
3302 a line cannot be fully displayed on the screen.
3309 Mappings prefixed with
3311 are used in header summaries, and they all understand the preconditions
3313 (the current message) and
3315 for elder messages (only honoured in conjunction with
3316 .Va datefield-markout-older ) .
3318 .Bl -tag -compact -width view-partinfo
3320 This mapping is used for the
3322 that can be created with the
3326 formats of the variable
3329 For the complete header summary line except the
3331 and the thread structure.
3333 For the thread structure which can be created with the
3335 format of the variable
3340 Mappings prefixed with
3342 are used when displaying messages.
3344 .Bl -tag -compact -width view-partinfo
3346 This mapping is used for so-called
3348 lines, which are MBOX file format specific header lines.
3351 A comma-separated list of headers to which the mapping applies may be
3352 given as a precondition; if the \*(OPal regular expression support is
3353 available then if any of the
3355 (extended) regular expression characters is seen the precondition will
3356 be evaluated as (an extended) one.
3358 For the introductional message info line.
3359 .It Ar view-partinfo
3360 For MIME part info lines.
3364 The following (case-insensitive) colour definitions and font attributes
3365 are understood, multiple of which can be specified in a comma-separated
3375 It is possible (and often applicable) to specify multiple font
3376 attributes for a single mapping.
3379 foreground colour attribute:
3389 To specify a 256-color mode a decimal number colour specification in
3390 the range 0 to 255, inclusive, is supported, and interpreted as follows:
3392 .Bl -tag -compact -width "999 - 999"
3394 the standard ISO 6429 colors, as above.
3396 high intensity variants of the standard colors.
3398 216 colors in tuples of 6.
3400 grayscale from black to white in 24 steps.
3402 .Bd -literal -offset indent
3404 fg() { printf "\e033[38;5;${1}m($1)"; }
3405 bg() { printf "\e033[48;5;${1}m($1)"; }
3407 while [ $i -lt 256 ]; do fg $i; i=$(($i + 1)); done
3408 printf "\e033[0m\en"
3410 while [ $i -lt 256 ]; do bg $i; i=$(($i + 1)); done
3411 printf "\e033[0m\en"
3415 background colour attribute (see
3417 for possible values).
3421 Mappings may be removed with the command
3423 For a generic overview see the section
3424 .Sx "Coloured display" .
3429 (C) Copy messages to files whose names are derived from the author of
3430 the respective message and do not mark them as being saved;
3431 otherwise identical to
3436 (c) Copy messages to the named file and do not mark them as being saved;
3437 otherwise identical to
3442 Show the name of the current working directory.
3446 \*(OP For unencrypted messages this command is identical to
3448 Encrypted messages are first decrypted, if possible, and then copied.
3452 \*(OP For unencrypted messages this command is identical to
3454 Encrypted messages are first decrypted, if possible, and then copied.
3458 Without arguments the current list of macros, including their content,
3459 is shown, otherwise a macro is defined.
3460 A macro definition is a sequence of commands in the following form:
3461 .Bd -literal -offset indent
3470 A defined macro can be invoked explicitly by using the
3474 commands, or implicitly if a macro hook is triggered, e.g., a
3476 Note that interpretation of
3478 depends on how (i.e.,
3480 normal macro, folder hook, hook, account switch) the macro is invoked.
3481 Macros can be deleted via
3485 Macro behaviour, including option localization, will change in v15.
3486 Please be aware of that and possibly embed a version check in a resource
3491 (d) Marks the given message list as
3493 Deleted messages will neither be saved in
3495 nor will they be available for most other commands.
3501 Superseded by the multiplexer
3507 Deletes the current message and displays the next message.
3508 If there is no next message, \*(UA says
3515 up or down by one message when given
3519 argument, respectively.
3523 Takes a message list and marks each given message as a draft.
3524 This mark has no technical meaning in the mail system;
3525 it just causes messages to be marked in the header summary,
3526 and makes them specially addressable.
3530 \*(NQ (ec) Echoes its arguments to standard output after applying
3532 expansions and filename transformations, as documented for
3539 except that is echoes to standard error.
3543 (e) Point the text editor (as defined in
3545 at each message from the given list in turn.
3546 Modified contents are discarded unless the
3553 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3554 conditional \(em if the condition of a preceding
3556 was false, check the following condition and execute the following block
3557 if it evaluates true.
3562 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3563 conditional \(em if none of the conditions of the preceding
3567 commands was true, the
3573 (en) Marks the end of an
3574 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3575 conditional execution block.
3580 \*(NQ \*(UA has a strict notion about which variables are
3581 .Sx "INTERNAL VARIABLES"
3582 and which are managed in the program
3584 Since some of the latter are a vivid part of \*(UAs functioning,
3585 however, they are transparently integrated into the normal handling of
3586 internal variables via
3590 To integrate other environment variables of choice into this
3591 transparent handling, and also to export internal variables into the
3592 process environment where they normally are not, a
3594 needs to become established with this command, as in, e.g.,
3597 .Dl environ link PERL5LIB from TZ
3600 Afterwards changing such variables with
3602 will cause automatic updates of the program environment, and therefore
3603 be inherited by newly created child processes.
3604 Sufficient system support provided (it was in BSD as early as 1987, and
3605 is standardized since Y2K) removing such variables with
3607 will remove them also from the program environment, but in any way
3608 the knowledge they ever have been
3611 Note this implies that
3613 may cause loss of links.
3618 will remove an existing link, but leaves the variables as such intact.
3619 Additionally the subcommands
3623 are provided, which work exactly the same as the documented commands
3627 but (additionally) link the variable(s) with the program environment and
3628 thus immediately export them to, or remove them from (if possible),
3629 respectively, the program environment.
3634 \*(OP Since \*(UA uses the console as a user interface it can happen
3635 that messages scroll by too fast to become recognized.
3636 Optionally an error message ring queue is available which stores
3637 duplicates of any error message and notifies the user in interactive
3638 sessions whenever a new error has occurred.
3639 The queue is finite: if its maximum size is reached any new message
3640 replaces the eldest.
3643 can be used to manage this message queue: if given
3645 or no argument the queue will be displayed and cleared,
3647 will only clear all messages from the queue.
3651 (ex or x) Exit from \*(UA without changing the active mailbox and skip
3652 any saving of messages in
3654 as well as a possibly tracked line editor history file.
3660 but open the mailbox readonly.
3664 (fi) The file command switches to a new mailbox.
3665 Without arguments it shows status information of the current mailbox.
3666 If an argument is given, it will write out changes (such as deletions)
3667 the user has made and open a new mailbox.
3668 Some special conventions are recognized for the
3672 .Bl -tag -compact -width ".Ar %:__lespec"
3674 (number sign) means the previous file,
3676 (percent sign) means the invoking user's system mailbox, which either
3677 is the (itself expandable)
3679 if that is set, the standardized absolute pathname indicated by
3681 if that is set, or a builtin compile-time default otherwise.
3683 means the primary system mailbox of
3685 (and never the value of
3687 regardless of its actual setting),
3689 (ampersand) means the invoking user's
3699 expands to the same value as
3701 but the file is handled as a primary system mailbox by, e.g., the
3705 commands, meaning that messages that have been read in the current
3706 session will be moved to the
3708 mailbox instead of simply being flagged as read.
3711 If the name matches one of the strings defined with the command
3713 it is replaced by its long form and expanded.
3714 If the name ends with
3719 it is treated as being compressed with
3724 respectively, and transparently handled through an intermediate
3725 (un)compression step (using a temporary file) with the according
3726 facility, sufficient support provided.
3727 Likewise, if the named file does not exist, but a file with one of the
3728 mentioned compression extensions does, then the name is automatically
3729 expanded and the compressed file is used.
3731 Otherwise, if the name ends with an extension for which
3732 .Va file-hook-load-EXTENSION
3734 .Va file-hook-save-EXTENSION
3735 variables are set, then the given hooks will be used to load and save
3737 and \*(UA will work with an intermediate temporary file.
3739 MBOX files (flat file-based mailboxes) are generally locked during file
3740 operations in order to avoid inconsistencies due to concurrent
3742 \*(OPal Mailbox files which \*(UA treats as the system
3745 and primary mailboxes will also be protected by so-called dotlock
3746 files, the traditional way of mail spool file locking: for any file
3750 will be created for the duration of the synchronization \(em
3751 as necessary a privilege-separated dotlock child process will be used
3752 to accommodate for necessary privilege adjustments in order to create
3753 the dotlock file in the same directory
3754 and with the same user and group identities as the file of interest.
3758 refers to a directory with the subdirectories
3763 then it is treated as a folder in
3765 format; \*(ID the variable
3767 can be used to control the format of yet non-existent folders.
3770 .Dl \*(IN protocol://[user[:password]@]host[:port][/path]
3771 .Dl \*(OU protocol://[user@]host[:port][/path]
3773 is taken as an Internet mailbox specification.
3774 The \*(OPally supported protocols are
3778 (POP3 with SSL/TLS encrypted transport).
3781 part is valid only for IMAP; there it defaults to
3783 Also see the section
3784 .Sx "On URL syntax and credential lookup" .
3788 contains special characters, in particular
3792 they must be escaped in URL notation \(en the command
3794 can be used to show the necessary conversion.
3798 Takes a message list and marks the messages as
3800 ged for urgent/special attention.
3801 This mark has no technical meaning in the mail system;
3802 it just causes messages to be highlighted in the header summary,
3803 and makes them specially addressable.
3812 With no arguments, list the names of the folders in the folder directory.
3813 With an existing folder as an argument,
3814 lists the names of folders below the named folder.
3820 but saves the message in a file named after the local part of the first
3821 recipient's address (instead of in
3828 but saves the message in a file named after the local part of the first
3829 recipient's address (instead of in
3836 but responds to all recipients regardless of the
3841 .It Ic followupsender
3844 but responds to the sender only regardless of the
3860 (f) Takes a list of message specifications and displays a summary of
3861 their message headers, exactly as via
3863 An alias of this command is
3866 .Sx "Specifying messages" .
3872 but saves the message in a file named after the local part of the
3873 recipient's address (instead of in
3878 Takes a message and the address of a recipient
3879 and forwards the message to him.
3880 The text of the original message is included in the new one,
3881 with the value of the
3883 variable preceding it.
3884 To filter the included header fields to the desired subset use the
3886 slot of the white- and blacklisting command
3888 Only the first part of a multipart message is included unless
3889 .Va forward-as-attachment ,
3890 and recipient addresses will be stripped from comments, names etc.
3891 unless the internal variable
3897 \*(OB Superseded by the multiplexer
3902 \*(OB Superseded by the multiplexer
3907 Define or list command aliases, so-called ghosts.
3908 Without arguments a list of all currently known aliases is shown.
3909 With one argument the expansion of the given alias is shown.
3910 With two or more arguments a command alias is defined or updated: the
3911 first argument is the name under which the remaining command line should
3912 be accessible, the content of which can be just about anything.
3913 A ghost can be used everywhere a normal command can be used, but always
3914 takes precedence; any arguments that are given to the command alias are
3915 joined onto the alias content, and the resulting string forms the
3916 command line that is, in effect, executed.
3919 .Bd -literal -offset indent
3921 `ghost': no such alias: "xx"
3924 ghost xx "echo hello,"
3934 \*(NQ Multiplexer command to establish white- and blacklisting
3935 selections of header fields for a variety of applications.
3936 Without any arguments the entire set of known contexts and their current
3937 settings is displayed.
3938 When given arguments, the first argument is the context to which the
3939 command applies, one of (case-insensitively)
3941 for display purposes (via, e.g.,
3944 for selecting which headers shall be stored persistently when
3950 ing messages (note that MIME related etc. header fields should not be
3951 ignored in order to not destroy usability of the message in this case),
3953 for stripping down messages when
3955 ing message (has no effect if
3956 .Va forward-as-attachment
3959 for defining user-defined set of fields for the command
3963 The current settings of the given context are displayed if only the
3964 first argument is given.
3965 A second argument denotes the type of restriction that is to be chosen,
3966 it may be (a case-insensitive prefix of)
3970 for white- and blacklisting purposes, respectively.
3971 Establishing a whitelist suppresses inspection of the corresponding
3973 If no further argument is given the current settings of the given type
3977 With four or more arguments the third denotes the action to be applied,
3982 for addition of fields, and
3986 for removal of fields from the given type of the given context.
3987 The fourth, and any following arguments are expected to specify the
3988 fields of desire, or \*(OPally, regular expression matches ought to
3990 The special wildcard field (asterisk,
3992 will establish a (fast) shorthand setting which covers all fields, or
3993 remove all fields in one operation, respectively.
3998 (h) Show the current group of headers, the size of which depends on
4001 and the style of which can be adjusted with the variable
4003 If a message-specification is given the group of headers containing the
4004 first message therein is shown and the message at the top of the screen
4019 the list of history entries;
4022 argument selects and shows the respective history entry \(en
4025 to accept it, and the history entry will become the new history top.
4026 The default mode if no arguments are given is
4033 Takes a message list and marks each message therein to be saved in the
4038 Does not override the
4041 \*(UA deviates from the POSIX standard with this command, because a
4043 command issued after
4045 will display the following message, not the current one.
4050 (i) Part of the nestable
4051 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
4052 conditional execution construct \(em if the given condition is true then
4053 the encapsulated block is executed.
4054 POSIX only supports the (case-insensitive) conditions
4059 end, all remaining conditions are non-portable extensions; note that
4060 falsely specified conditions cause the execution of the entire
4061 conditional construct until the (matching) closing
4063 command to be suppressed.
4064 The syntax of the nestable
4066 conditional execution construct requires that each condition and syntax
4067 element is surrounded by whitespace.
4069 .Bd -literal -offset indent
4078 The (case-insensitive) condition
4080 erminal will evaluate to true if the standard input is a terminal, i.e.,
4081 in interactive sessions.
4082 Another condition can be any boolean value (see the section
4083 .Sx "INTERNAL VARIABLES"
4084 for textual boolean representations) to mark an enwrapped block as
4087 .Dq always execute .
4088 It is possible to check
4089 .Sx "INTERNAL VARIABLES"
4092 variables for existence or compare their expansion against a user given
4093 value or another variable by using the
4095 .Pf ( Dq variable next )
4096 conditional trigger character;
4097 a variable on the right hand side may be signalled using the same
4099 The variable names may be enclosed in a pair of matching braces.
4102 The available comparison operators are
4106 (less than or equal to),
4112 (greater than or equal to),
4116 (is substring of) and
4118 (is not substring of).
4119 The values of the left and right hand side are treated as strings and
4120 are compared 8-bit byte-wise, ignoring case according to the rules of
4121 the US-ASCII encoding (therefore, dependent on the active locale,
4122 possibly producing false results for strings in the locale encoding).
4123 Except for the substring checks the comparison will instead be performed
4124 arithmetically if both, the user given value as well as the variable
4125 content, can be parsed as numbers (integers).
4126 An unset variable is treated as the empty string.
4129 When the \*(OPal regular expression support is available, the additional
4135 They treat the right hand side as an extended regular expression that is
4136 matched case-insensitively and according to the active
4138 locale, meaning that strings in the locale encoding should be matched
4142 Conditions can be joined via AND-OR lists (where the AND operator is
4144 and the OR operator is
4146 which have equal precedence and will be evaluated with left
4147 associativity, thus using the same syntax that is known for the
4149 It is also possible to form groups of conditions and lists by enclosing
4150 them in pairs of brackets
4151 .Ql [\ \&.\&.\&.\ ] ,
4152 which may be interlocked within each other, and also be joined via
4156 The results of individual conditions and entire groups may be modified
4157 via unary operators: the unary operator
4159 will reverse the result.
4161 .Bd -literal -offset indent
4165 if $ttycharset == "UTF-8"
4166 echo *ttycharset* is set to UTF-8, case-insensitively
4170 echo These two variables are equal
4172 if $version-major >= 15
4173 echo Running a new version..
4174 if $features =@ +regex
4175 if $TERM =~ "^xterm\&.*"
4176 echo ..in an X terminal
4179 if [ [ true ] && [ [ ${debug} ] || [ $verbose ] ] ]
4182 if true && $debug || ${verbose}
4183 echo Left associativity, as is known from the shell
4185 if ! ! true && ! [ ! $debug && ! $verbose ]
4186 echo Unary operator support
4196 Superseded by the multiplexer
4201 Shows the names of all available commands, alphabetically sorted.
4202 If given any non-whitespace argument the list will be shown in the order
4203 in which command prefixes are searched.
4206 output is available.
4210 This command can be used to localize changes to variables, meaning that
4211 their state will be reverted to the former one once the covered scope
4213 It can only be used inside of macro definition blocks introduced by
4217 and is interpreted as a boolean (string, see
4218 .Sx "INTERNAL VARIABLES" ) ;
4221 of an account is left once it is switched off again.
4222 .Bd -literal -offset indent
4223 define temporary_settings {
4238 enables change localization and calls
4240 which explicitly resets localization, then any value changes within
4242 will still be reverted by
4244 \*(ID Once the outermost level, the one which enabled localization
4245 first, is left, but no earlier, all adjustments will be unrolled.
4246 \*(ID Likewise worth knowing, if in this example
4248 changes to a different
4250 which sets some variables that are yet covered by localizations, their
4251 scope will be extended, and in fact leaving the
4253 will (thus) restore settings in (likely) global scope which actually
4254 were defined in a local, private context.
4258 Reply to messages that come in via known
4261 .Pf ( Ic mlsubscribe )
4262 mailing lists, or pretend to do so (see
4263 .Sx "Mailing lists" ) :
4266 functionality this will actively resort and even remove message
4267 recipients in order to generate a message that is supposed to be sent to
4269 For example it will also implicitly generate a
4270 .Ql Mail-Followup-To:
4271 header if that seems useful, regardless of the setting of the variable
4278 but saves the message in a file named after the local part of the first
4279 recipient's address (instead of in
4284 (m) Takes a (list of) recipient address(es) as (an) argument(s),
4285 or asks on standard input if none were given;
4286 then collects the remaining mail content and sends it out.
4290 (mb) The given message list is to be sent to
4292 when \*(UA is quit; this is the default action unless the variable
4295 \*(ID This command can only be used in a primary system mailbox (see
4300 Without any arguments the content of the MIME type cache will displayed.
4301 Otherwise each argument defines a complete MIME type specification of
4302 a type that shall be added (prepended) to the cache.
4303 In any event MIME type sources are loaded first as necessary \(en
4304 .Va mimetypes-load-control
4305 can be used to fine-tune which sources are actually loaded.
4306 Refer to the section on
4307 .Sx "The mime.types files"
4308 for more on MIME type specifications and this topic in general.
4309 MIME type unregistration and cache resets can be triggered with
4314 Without arguments the list of all currently defined mailing lists
4315 (and their attributes, if any) is shown; a more verbose listing will be
4316 produced if either of
4321 Otherwise all given arguments (which need not be quoted except for
4322 whitespace) will be added and henceforth be recognized as mailing lists.
4323 Mailing lists may be removed via the command
4326 If the \*(OPal regular expression support is available then mailing
4327 lists may also be specified as (extended) regular expressions (see
4333 Without arguments the list of all currently defined mailing lists which
4334 have a subscription attribute is shown; a more verbose listing will be
4335 produced if either of
4340 Otherwise this attribute will be set for all given mailing lists,
4341 newly creating them as necessary (as via
4343 Subscription attributes may be removed via the command
4352 but moves the messages to a file named after the local part of the
4353 sender address of the first message (instead of in
4360 but marks the messages for deletion if they were transferred
4367 but also displays header fields which would not pass the
4369 selection, and all MIME parts.
4377 on the given messages, even in non-interactive mode and as long as the
4378 standard output is a terminal.
4384 \*(OP When used without arguments or if
4386 has been given the content of the
4388 cache is shown, loading it first as necessary.
4391 then the cache will only be initialized and
4393 will remove its contents.
4394 Note that \*(UA will try to load the file only once, use
4395 .Ql Ic \&\&netrc Ns \:\0\:clear
4396 to unlock further attempts.
4401 .Sx "On URL syntax and credential lookup" ;
4403 .Sx "The .netrc file"
4404 documents the file format in detail.
4408 Checks for new mail in the current folder without committing any changes
4410 If new mail is present, a message is shown.
4414 the headers of each new message are also shown.
4415 This command is not available for all mailbox types.
4423 Goes to the next message in sequence and types it.
4424 With an argument list, types the next matching message.
4438 If the current folder is accessed via a network connection, a
4440 command is sent, otherwise no operation is performed.
4446 but also displays header fields which would not pass the
4448 selection, and all MIME parts.
4456 on the given messages, even in non-interactive mode and as long as the
4457 standard output is a terminal.
4465 but also pipes header fields which would not pass the
4467 selection, and all parts of MIME
4468 .Ql multipart/alternative
4473 (pi) Takes a message list and a shell command
4474 and pipes the messages through the command.
4475 Without an argument the current message is piped through the command
4482 every message is followed by a formfeed character.
4503 (q) Terminates the session, saving all undeleted, unsaved messages in
4506 preserving all messages marked with
4510 or never referenced in the system
4512 and removing all other messages from the primary system mailbox.
4513 If new mail has arrived during the session,
4515 .Dq You have new mail
4517 If given while editing a mailbox file with the command line flag
4519 then the edit file is rewritten.
4520 A return to the shell is effected,
4521 unless the rewrite of edit file fails,
4522 in which case the user can escape with the exit command.
4526 \*(NQ Read a line from standard input, and assign the splitted and
4527 trimmed line data to the given variables.
4528 If there are more fields than variables, assign successive fields to the
4529 last given variable.
4530 If there are less fields than variables, assign the empty string to the
4532 \*(ID This command will likely be extended towards more
4534 compatibility: for now splitting always occurs at whitespace, reverse
4535 solidus newline escaping is always supported, and the \*(OPal line
4536 editing features are always available when on an interactive terminal.
4537 .Bd -literal -offset indent
4540 ? echo "<$a> <$b> <$c>"
4556 Removes the named files or directories.
4557 If a name refer to a mailbox, e.g., a Maildir mailbox, then a mailbox
4558 type specific removal will be performed, deleting the complete mailbox.
4559 The user is asked for confirmation in interactive mode.
4563 Takes the name of an existing folder
4564 and the name for the new folder
4565 and renames the first to the second one.
4566 Both folders must be of the same type.
4570 (R) Reply to originator.
4571 Does not reply to other recipients of the original message.
4573 will exchange this command with
4575 Unless the internal variable
4577 is set the recipient address will be stripped from comments, names etc.
4581 (r) Take a message and group-responds to it by addressing the sender
4584 .Va followup-to-honour ,
4587 .Va recipients-in-cc
4588 influence response behaviour.
4591 offers special support for replying to mailing lists.
4592 Unless the internal variable
4594 is set recipient addresses will be stripped from comments, names etc.
4607 but initiates a group-reply regardless of the value of
4614 but responds to the sender only regardless of the value of
4621 but does not add any header lines.
4622 This is not a way to hide the sender's identity,
4623 but useful for sending a message again to the same recipients.
4627 Takes a list of messages and a user name
4628 and sends each message to the named user.
4630 and related header fields are prepended to the new copy of the message.
4648 .It Ic respondsender
4654 (ret) Superseded by the multiplexer
4661 but saves the messages in a file named after the local part of the
4662 sender of the first message instead of (in
4664 and) taking a filename argument.
4668 (s) Takes a message list and a filename and appends each message in turn
4669 to the end of the file.
4670 If no filename is given, the
4673 The filename in quotes, followed by the generated character count
4674 is echoed on the user's terminal.
4675 If editing a primary system mailbox the messages are marked for deletion.
4676 Filename interpretation as described for the
4678 command is performed.
4682 \*(OB Superseded by the multiplexer
4687 \*(OB Superseded by the multiplexer
4692 \*(OB Superseded by the multiplexer
4697 Takes a message specification (list) and displays a header summary of
4698 all matching messages, as via
4700 This command is an alias of
4703 .Sx "Specifying messages" .
4707 Takes a message list and marks all messages as having been read.
4711 (se) Without arguments this command shows all internal variables which
4712 are currently known to \*(UA (they have been set).
4713 A more verbose listing will be produced if either of
4717 are set, in which case variables may be preceded with a comment line
4718 that gives some context of what \*(UA knows about the given variable.
4720 Otherwise the given variables (and arguments) are set or adjusted.
4721 Arguments are of the form
4723 (no space before or after
4727 if there is no value, i.e., a boolean variable.
4728 Quotation marks may be placed around any part of the assignment
4729 statement to quote blanks or tabs, e.g.,
4731 .Dl set indentprefix='->'
4733 If an argument begins with
4737 the effect is the same as invoking the
4739 command with the remaining part of the variable
4740 .Pf ( Ql unset save ) .
4744 that is known to map to an environment variable will automatically cause
4745 updates in the program environment (unsetting a variable in the
4746 environment requires corresponding system support).
4747 Please use the command
4749 for further environmental control.
4754 .Sx "INTERNAL VARIABLES"
4760 (sh) Invokes an interactive version of the shell.
4764 Without arguments the list of all currently defined shortcuts is
4766 Otherwise all given arguments (which need not be quoted except for
4767 whitespace) are treated as pairs of shortcuts and their expansions,
4768 creating new or changing already existing shortcuts, as necessary.
4769 Shortcuts may be removed via the command
4771 The expansion strings should be in the syntax that has been described
4780 but performs neither MIME decoding nor decryption, so that the raw
4781 message text is shown.
4785 (si) Shows the size in characters of each message of the given
4790 Shows the current sorting criterion when used without an argument.
4791 Otherwise creates a sorted representation of the current folder,
4794 command and the addressing modes such that they refer to messages in
4796 Message numbers are the same as in regular mode.
4800 a header summary in the new order is also displayed.
4801 Automatic folder sorting can be enabled by setting the
4803 variable, as in, e.g.,
4804 .Ql set autosort=thread .
4805 Possible sorting criterions are:
4807 .Bl -tag -compact -width "subject"
4809 Sort the messages by their
4811 field, that is by the time they were sent.
4813 Sort messages by the value of their
4815 field, that is by the address of the sender.
4818 variable is set, the sender's real name (if any) is used.
4820 Sort the messages by their size.
4822 \*(OP Sort the message by their spam score, as has been classified by
4825 Sort the messages by their message status.
4827 Sort the messages by their subject.
4829 Create a threaded display.
4831 Sort messages by the value of their
4833 field, that is by the address of the recipient.
4836 variable is set, the recipient's real name (if any) is used.
4841 (so) The source command reads commands from the given file, which is
4842 subject to the usual filename expansions (see introductional words of
4844 If the given argument ends with a vertical bar
4846 then the argument will instead be interpreted as a shell command and
4847 \*(UA will read the output generated by it.
4848 Interpretation of commands read is stopped when an error is encountered.
4851 cannot be used from within macros that execute as
4852 .Va folder-hook Ns s
4855 i.e., it can only be called from macros that were
4862 (beside not supporting pipe syntax aka shell command input) is that
4863 this command will not generate an error if the given file argument
4864 cannot be opened successfully.
4868 \*(OP Takes a list of messages and clears their
4874 \*(OP Takes a list of messages and causes the
4876 to forget it has ever used them to train its Bayesian filter.
4877 Unless otherwise noted the
4879 flag of the message is inspected to chose whether a message shall be
4887 \*(OP Takes a list of messages and informs the Bayesian filter of the
4891 This also clears the
4893 flag of the messages in question.
4897 \*(OP Takes a list of messages and rates them using the configured
4898 .Va spam-interface ,
4899 without modifying the messages, but setting their
4901 flag as appropriate; because the spam rating headers are lost the rate
4902 will be forgotten once the mailbox is left.
4903 Refer to the manual section
4905 for the complete picture of spam handling in \*(UA.
4909 \*(OP Takes a list of messages and sets their
4915 \*(OP Takes a list of messages and informs the Bayesian filter of the
4921 flag of the messages in question.
4930 Create a threaded representation of the current folder,
4931 i.\|e. indent messages that are replies to other messages in the header
4932 display and change the
4934 command and the addressing modes such that they refer to messages in the
4936 Message numbers are the same as in unthreaded mode.
4940 a header summary in threaded order is also displayed.
4949 slot for white- and blacklisting header fields.
4953 (to) Takes a message list and types out the first
4955 lines of each message on the users' terminal.
4956 Unless a special selection has been established for the
4960 command, the only header fields that are displayed are
4971 It is possible to apply compression to what is displayed by setting
4973 Messages are decrypted and converted to the terminal character set
4978 (tou) Takes a message list and marks the messages for saving in
4980 \*(UA deviates from the POSIX standard with this command,
4983 command will display the following message instead of the current one.
4989 but also displays header fields which would not pass the
4991 selection, and all parts of MIME
4992 .Ql multipart/alternative
4997 (t) Takes a message list and types out each message on the users'
5001 For MIME multipart messages, all parts with a content type of
5005 are shown, the other are hidden except for their headers.
5006 Messages are decrypted and converted to the terminal character set
5011 Delete all given accounts.
5012 An error message is shown if a given account is not defined.
5015 will discard all existing accounts.
5019 (una) Takes a list of names defined by alias commands
5020 and discards the remembered groups of users.
5023 will discard all existing aliases.
5027 Takes a message list and marks each message as not having been answered.
5033 ing, specified by its context and input sequence, both of which may be
5034 specified as a wildcard (asterisk,
5038 will remove all bindings of all contexts.
5042 Only applicable to threaded mode.
5043 Takes a message list and makes the message and all replies to it visible
5044 in header summaries again.
5045 When a message becomes the current message,
5046 it is automatically made visible.
5047 Also when a message with collapsed replies is displayed,
5048 all of these are automatically uncollapsed.
5054 mapping for the given colour type (see
5056 for a list of types) and mapping; if the optional precondition argument
5057 is used then only the exact tuple of mapping and precondition is removed.
5060 will remove all mappings (no precondition allowed).
5062 .Sx "Coloured display"
5063 for the general picture.
5067 Undefine all given macros.
5068 An error message is shown if a given macro is not defined.
5071 will discard all existing macros.
5075 (u) Takes a message list and marks each message as not being deleted.
5079 Takes a message list and
5085 Takes a message list and marks each message as not being
5090 \*(OB Superseded by the multiplexer
5095 \*(OB Superseded by the multiplexer
5100 Remove all the given command
5104 will remove all ghosts.
5108 Superseded by the multiplexer
5113 Delete all given MIME types, e.g.,
5114 .Ql unmimetype text/plain
5115 will remove all registered specifications for the MIME type
5119 will discard all existing MIME types, just as will
5121 but which also reenables cache initialization via
5122 .Va mimetypes-load-control .
5126 Forget about all the given mailing lists.
5129 will remove all lists.
5134 .It Ic unmlsubscribe
5135 Remove the subscription attribute from all given mailing lists.
5138 will clear the attribute from all lists which have it set.
5149 Takes a message list and marks each message as not having been read.
5153 Superseded by the multiplexer
5158 \*(OB Superseded by the multiplexer
5163 \*(OB Superseded by the multiplexer
5168 (uns) Takes a list of internal variable names and discards their
5169 remembered values; the reverse of
5176 Deletes the shortcut names given as arguments.
5179 will remove all shortcuts.
5183 Disable sorted or threaded mode
5189 return to normal message order and,
5193 displays a header summary.
5203 Perform URL percent codec operations, rather according to RFC 3986,
5204 on all given strings.
5205 This is character set agnostic and thus locale dependent, and it may
5206 decode bytes which are invalid in the current locale, unless the input
5207 solely consists of characters in the portable character set, see
5208 .Sx "Character sets" .
5209 The first argument specifies the operation:
5213 perform plain URL percent en- and decoding, respectively.
5217 perform a slightly modified operation which should be better for
5218 pathnames: it does not allow a tilde
5220 and will neither accept hyphen
5224 as an initial character.
5228 Edit the values of or create the given variable(s) in the
5230 Boolean variables cannot be edited.
5234 This command produces the same output as the listing mode of
5238 ity adjustments, but only for the given variables.
5242 \*(OP Takes a message list and verifies each message.
5243 If a message is not a S/MIME signed message,
5244 verification will fail for it.
5245 The verification process checks if the message was signed using a valid
5247 if the message sender's email address matches one of those contained
5248 within the certificate,
5249 and if the message content has been altered.
5261 (v) Takes a message list and invokes the display editor on each message.
5262 Modified contents are discarded unless the
5268 (w) For conventional messages the body without all headers is written.
5269 The original message is never marked for deletion in the originating
5271 The output is decrypted and converted to its native format as necessary.
5272 If the output file exists, the text is appended.
5273 If a message is in MIME multipart format its first part is written to
5274 the specified file as for conventional messages, handling of the remains
5275 depends on the execution mode.
5276 No special handling of compressed files is performed.
5278 In interactive mode the user is consecutively asked for the filenames of
5279 the processed parts.
5280 For convience saving of each part may be skipped by giving an empty
5281 value, the same result as writing it to
5283 Shell piping the part content by specifying a leading vertical bar
5285 character for the filename is supported.
5286 Other user input is expanded as usually for folders, e.g., tilde
5287 expansion is performed, and contents of the destination file are
5288 overwritten if the file previously existed.
5290 \*(ID In non-interactive mode any part which does not specify a filename
5291 is ignored, and suspicious parts of filenames of the remaining parts are
5292 URL percent encoded (as via
5294 to prevent injection of malicious character sequences, resulting in
5295 a filename that will be written into the current directory.
5296 Existing files will not be overwritten, instead the part number or
5297 a dot are appended after a number sign
5299 to the name until file creation succeeds (or fails due to other
5309 \*(UA presents message headers in
5311 fuls as described under the
5314 Without arguments this command scrolls to the next window of messages,
5315 likewise if the argument is
5319 scrolls to the last,
5321 scrolls to the first, and
5326 A number argument prefixed by
5330 indicates that the window is calculated in relation to the current
5331 position, and a number without a prefix specifies an absolute position.
5337 but scrolls to the next or previous window that contains at least one
5346 .\" .Sh COMMAND ESCAPES {{{
5347 .Sh "COMMAND ESCAPES"
5349 Here is a summary of the command escapes available in compose mode,
5350 which are used to perform special functions when composing messages.
5351 Command escapes are only recognized at the beginning of lines.
5352 The actual escape character can be set via the internal variable
5354 it defaults to the tilde
5358 .Bl -tag -width indent
5361 Insert the string of text in the message prefaced by a single
5363 (If the escape character has been changed,
5364 that character must be doubled
5365 in order to send it at the beginning of a line.)
5368 .It Ic ~! Ar command
5369 Execute the indicated shell
5371 which follows, replacing unescaped exclamation marks with the previously
5372 executed command if the internal variable
5374 is set, then return to the message.
5378 Same effect as typing the end-of-file character.
5381 .It Ic ~: Ar \*(UA-command Ns \0or Ic ~_ Ar \*(UA-command
5382 Execute the given \*(UA command.
5383 Not all commands, however, are allowed.
5387 Write a summary of command escapes.
5390 .It Ic ~< Ar filename
5395 .It Ic ~<! Ar command
5397 is executed using the shell.
5398 Its standard output is inserted into the message.
5401 .It Ic ~@ Op Ar filename...
5404 arguments are specified they are treated as a file list of
5408 arguments, optionally also separated by commas, which are expanded and
5409 then appended to the existing list of message attachments.
5410 It is not possible to add message attachments with this method, and
5411 (text) attachments are implicitly assumed to be in
5413 encoding, and will thus be evaluated as documented in the section
5414 .Sx "Character sets" .
5416 Without arguments, in non-interactive mode, for reproduceabilities sake,
5417 there will always be two questions for each attachment, regardless of
5418 whether character set conversion is available and what the file
5420 The first question expects the filename, and the second the the input
5421 character set to be passed through to the corresponding MIME parameter;
5422 no conversion will be tried if there is input to the latter question,
5423 otherwise the usual conversion algorithm as documented in
5424 .Sx "Character sets" ,
5426 For message attachments, the input to the second question is ignored.
5428 In interactive mode, without arguments, the attachment list is edited.
5429 If an attachment's file name is left empty,
5430 that attachment is deleted from the list.
5431 When the end of the attachment list is reached,
5432 \*(UA will ask for further attachments until an empty name is given.
5433 If a given file name solely consists of the number sign
5435 followed by a valid message number of the currently active mailbox, then
5436 the given message is attached as a MIME
5438 part and the rest of this section does not apply.
5440 If character set conversion has been compiled into \*(UA, then this mode
5441 gives the user the option to specify input and output character sets,
5442 unless the file extension indicates binary content, in which case \*(UA
5443 asks whether this step shall be skipped for the attachment in question.
5444 If not skipped, then the charset that succeeds to represent the
5445 attachment data will be used in the
5447 MIME parameter of the mail message:
5449 .Bl -bullet -compact
5451 If input and output character sets are specified, then the conversion is
5452 performed on the fly.
5453 The user will be asked repeatedly until the desired conversion succeeds.
5455 If only an output character set is specified, then the input is assumed
5458 charset and will be converted to the given output charset on the fly.
5459 The user will be asked repeatedly until the desired conversion succeeds.
5461 If no character sets are specified at all then the algorithm that is
5462 documented in the section
5463 .Sx "Character sets"
5464 is applied, but directly and on the fly.
5465 The user will be asked repeatedly until the desired conversion succeeds.
5467 Finally, if an input-, but no output character set is specified, then no
5468 conversion is ever performed, but the
5470 MIME parameter value will still be set to the user input.
5472 The character set selection loop can be left by typing
5474 i.e., causing an interrupt.
5475 .\" \*(OU next sentence
5476 Note that before \*(UA v15.0 this terminates the entire
5477 current attachment selection, not only the character set selection.
5480 Without character set conversion support, \*(UA will ask for the input
5481 character set only, and it will set the
5483 MIME parameter value to the given input, if any;
5484 if no user input is seen then the
5486 character set will be used for the parameter value instead.
5487 Note that the file extension check is not performed in this mode, since
5488 no conversion will take place anyway.
5492 Inserts the string contained in the
5495 .Ql Ic ~i Ns \0Sign ) .
5500 ting the variable(s) instead!) The escape sequences tabulator
5508 Inserts the string contained in the
5511 .Ql Ic ~i Ns \0sign ) .
5516 ting the variable(s) instead!) The escape sequences tabulator
5523 .It Ic ~b Ar name ...
5524 Add the given names to the list of blind carbon copy recipients.
5527 .It Ic ~c Ar name ...
5528 Add the given names to the list of carbon copy recipients.
5532 Read the file specified by the
5534 variable into the message.
5538 Invoke the text editor on the message collected so far.
5539 After the editing session is finished,
5540 the user may continue appending text to the message.
5543 .It Ic ~F Ar messages
5544 Read the named messages into the message being sent, including all
5545 message headers and MIME parts.
5546 If no messages are specified, read in the current message.
5549 .It Ic ~f Ar messages
5550 Read the named messages into the message being sent.
5551 If no messages are specified, read in the current message.
5552 Strips down the list of header fields according to the
5554 white- and blacklist selection of
5556 For MIME multipart messages,
5557 only the first displayable part is included.
5561 Edit the message header fields
5566 by typing each one in turn and allowing the user to edit the field.
5567 The default values for these fields originate from the
5575 Edit the message header fields
5581 by typing each one in turn and allowing the user to edit the field.
5584 .It Ic ~i Ar variable
5585 Insert the value of the specified variable into the message,
5586 adding a newline character at the end.
5587 The message remains unaltered if the variable is unset or empty.
5592 ting the variable(s) instead!) The escape sequences tabulator
5599 .It Ic ~M Ar messages
5600 Read the named messages into the message being sent,
5603 If no messages are specified, read the current message.
5606 .It Ic ~m Ar messages
5607 Read the named messages into the message being sent,
5610 If no messages are specified, read the current message.
5611 Strips down the list of header fields according to the
5613 white- and blacklist selection of
5615 For MIME multipart messages,
5616 only the first displayable part is included.
5620 Display the message collected so far,
5621 prefaced by the message header fields
5622 and followed by the attachment list, if any.
5626 Abort the message being sent,
5627 copying it to the file specified by the
5634 .It Ic ~R Ar filename
5635 Read the named file into the message, indented by
5639 .It Ic ~r Ar filename
5640 Read the named file into the message.
5644 Cause the named string to become the current subject field.
5645 Newline (NL) and carriage-return (CR) bytes are invalid and will be
5646 normalized to space (SP) characters.
5649 .It Ic ~t Ar name ...
5650 Add the given name(s) to the direct recipient list.
5653 .It Ic ~U Ar messages
5654 Read in the given / current message(s) excluding all headers, indented by
5658 .It Ic ~u Ar messages
5659 Read in the given / current message(s), excluding all headers.
5663 Invoke an alternate editor (defined by the
5665 environment variable) on the message collected so far.
5666 Usually, the alternate editor will be a screen editor.
5667 After the editor is quit,
5668 the user may resume appending text to the end of the message.
5671 .It Ic ~w Ar filename
5672 Write the message onto the named file.
5674 the message is appended to it.
5680 except that the message is not saved at all.
5683 .It Ic ~| Ar command
5684 Pipe the message through the specified filter command.
5685 If the command gives no output or terminates abnormally,
5686 retain the original text of the message.
5689 is often used as a rejustifying filter.
5693 .It Ic ~^ Op Ar cmd Op Ar subcmd Op Ar header-name Op Ar header-body
5694 Low-level command ment for scripted message access, i.e., for
5695 .Va on-compose-done-shell
5697 .Va on-compose-done .
5698 The used protocol is likely subject to changes, and therefore the
5699 mentioned hooks receive the used protocol version as an initial line.
5700 In general the first field of a response line represents a status code
5701 which specifies whether a command was successful or not, whether result
5702 data is to be expected, and if, the format of the result data.
5703 The status codes are:
5706 .Bl -tag -compact -width _210_
5708 Status ok; the remains of the line are the result.
5710 Status ok; the rest of the line is optionally used for more status.
5711 What follows are lines of result addresses, terminated by an empty line.
5712 The address lines consist of two fields, the first of which is the
5713 plain address, e.g.,
5715 separated by a single ASCII SP space from the second which contains the
5716 unstripped address, even if that is identical to the first field, e.g.,
5717 .Ql (Lovely) Bob <bob@exam.ple> .
5719 Status ok; the rest of the line is optionally used for more status.
5720 What follows are lines of furtherly unspecified string content,
5721 terminated by an empty line.
5723 Syntax error; invalid command.
5725 Syntax error in parameters or arguments.
5727 Error: an argument fails verification.
5728 For example an invalid address has been specified.
5730 Error: an otherwise valid argument is rendered invalid due to context.
5731 For example, a second address is added to a header which may consist of
5732 a single address only.
5736 If a command indicates failure then the message will have remained
5738 The following commands are supported:
5742 .Bl -tag -compact -width headers
5744 This command allows listing, inspection, and editing of message headers.
5745 The second argument specifies the subcommand to apply, one of:
5748 .Bl -tag -compact -width remove
5750 Without a third argument a list of all yet existing headers is given via
5752 this command is the default command of
5754 if no second argument has been given.
5755 A third argument restricts output to the given header only, which may
5758 if no such field is defined.
5761 Shows the content of the header given as the third argument.
5762 Dependent on the header type this may respond with
5766 any failure results in
5770 This will remove all instances of the header given as the third
5775 if no such header can be found.
5778 Create a new or an additional instance of the header given in the third
5779 argument, with the header body content as given in the fourth argument
5780 (the remains of the line).
5783 if the third argument specifies a free-form header field name that is
5784 invalid, or if body content extraction fails to succeed,
5786 if any extracted address does not pass syntax and/or security checks, and
5788 to indicate prevention of excessing a single-instance header \(em note that
5790 can be appended to (a space separator will be added automatically first).
5792 is returned upon success.
5801 .\" .Sh INTERNAL VARIABLES {{{
5802 .Sh "INTERNAL VARIABLES"
5804 Internal \*(UA variables are controlled via the
5808 commands; prefixing a variable name with the string
5812 has the same effect as using
5818 Creation or editing of variables can be performed in the
5823 will give more insight on the given variable(s), and
5825 when called without arguments, will show a listing of all variables.
5826 Both commands support a more
5829 Some well-known variables will also become inherited from the
5832 implicitly, others can be explicitly imported with the command
5834 and henceforth share the said properties.
5837 Two different kind of internal variables exist.
5838 There are boolean variables, which can only be in one of the two states
5842 and value variables with a(n optional) string value.
5843 For the latter proper quoting is necessary upon assignment time, the
5844 introduction of the section
5846 documents the supported quoting rules.
5848 .Bd -literal -offset indent
5849 wysh set one=val\e 1 two="val 2" \e
5850 three='val "3"' four=$'val \e'4\e''
5851 varshow one two three four
5852 unset one two three four
5856 Dependent upon the actual option the string values will be interpreted
5857 as numbers, colour names, normal text etc., but there also exists
5858 a special kind of string value, the
5859 .Dq boolean string ,
5860 which must either be a decimal integer (in which case
5864 and any other value is true) or any of the (case-insensitive) strings
5870 for a false boolean and
5876 for a true boolean; a special kind of boolean string is the
5878 which is a boolean string that can optionally be prefixed with the
5879 (case-insensitive) term
5883 which causes prompting of the user in interactive mode, with the given
5884 boolean as the default value.
5886 .\" .Ss "Initial settings" {{{
5887 .\" (Keep in SYNC: ./nail.h:okeys, ./nail.rc, ./nail.1:"Initial settings")
5888 .Ss "Initial Settings"
5890 The standard POSIX 2008/Cor 2-2016 mandates the following initial
5896 .Pf no Va autoprint ,
5910 .Pf no Va ignoreeof ,
5912 .Pf no Va keepsave ,
5914 .Pf no Va outfolder ,
5922 .Pf no Va sendwait ,
5931 Notes: \*(UA does not support the
5933 variable \(en use command line options or
5935 to pass options through to a
5937 And the default global
5939 file (which is loaded unless the
5941 command line flag has been used or the
5942 .Ev NAIL_NO_SYSTEM_RC
5943 environment variable is set) bends those initial settings a bit, e.g.,
5944 it sets the variables
5949 to name a few, establishes a default
5951 selection etc., and should thus be taken into account.
5954 .\" .Ss "Variables" {{{
5957 .Bl -tag -width ".It Va _utoprin_"
5959 .It Va -account-name
5960 \*(RO Is set to the active
5965 \*(RO The status of the last command.
5968 .It Va -folder-resolved
5969 \*(RO Set to the fully resolved path of
5971 once that evaluation has occurred; rather internal.
5974 .It Va -mailbox-display
5975 \*(RO The name of the current mailbox
5977 possibly abbreviated for display purposes.
5980 .It Va -mailbox-resolved
5981 \*(RO The fully resolved path of the current mailbox.
5984 .It Va add-file-recipients
5985 \*(BO When file or pipe recipients have been specified,
5986 mention them in the corresponding address fields of the message instead
5987 of silently stripping them from their recipient list.
5988 By default such addressees are not mentioned.
5992 \*(BO Causes only the local part to be evaluated
5993 when comparing addresses.
5997 \*(BO Causes messages saved in
5999 to be appended to the end rather than prepended.
6000 This should always be set.
6004 \*(BO Causes \*(UA to prompt for the subject of each message sent.
6005 If the user responds with simply a newline,
6006 no subject field will be sent.
6010 \*(BO Causes the prompts for
6014 lists to appear after the message has been edited.
6018 \*(BO If set, \*(UA asks for files to attach at the end of each message,
6019 shall the list be found empty at that time.
6020 An empty line finalizes the list.
6024 \*(BO Causes the user to be prompted for carbon copy recipients
6025 (at the end of each message if
6029 are set) shall the list be found empty (at that time).
6030 An empty line finalizes the list.
6034 \*(BO Causes the user to be prompted for blind carbon copy
6035 recipients (at the end of each message if
6039 are set) shall the list be found empty (at that time).
6040 An empty line finalizes the list.
6044 \*(BO\*(OP Causes the user to be prompted if the message is to be
6045 signed at the end of each message.
6048 variable is ignored when this variable is set.
6052 \*(BO Alternative name for
6059 .It Va attachment-ask-content-description , \
6060 attachment-ask-content-disposition , \
6061 attachment-ask-content-id , \
6062 attachment-ask-content-type
6063 \*(BO If set then the user will be prompted for some attachment
6064 information when editing the attachment list.
6065 It is advisable to not use these but for the first of the variables;
6066 even for that it has to be noted that the data is used
6072 A sequence of characters to display in the
6076 as shown in the display of
6078 each for one type of messages (see
6079 .Sx "Message states" ) ,
6080 with the default being
6083 .Ql NU\ \ *HMFAT+\-$~
6086 variable is set, in the following order:
6088 .Bl -tag -compact -width ".It Ql _"
6110 start of a collapsed thread.
6112 an uncollapsed thread (TODO ignored for now).
6116 classified as possible spam.
6122 Specifies a list of recipients to which a blind carbon copy of each
6123 outgoing message will be sent automatically.
6127 Specifies a list of recipients to which a carbon copy of each outgoing
6128 message will be sent automatically.
6132 \*(BO Causes threads to be collapsed automatically when threaded mode
6139 \*(BO Causes the delete command to behave like
6141 thus, after deleting a message the next one will be typed automatically.
6145 \*(BO\*(OB Causes threaded mode (see the
6147 command) to be entered automatically when a folder is opened.
6149 .Ql autosort=thread .
6153 Causes sorted mode (see the
6155 command) to be entered automatically with the value of this variable as
6156 sorting method when a folder is opened, e.g.,
6157 .Ql set autosort=thread .
6161 \*(BO Enables the substitution of all not (reverse-solidus) escaped
6164 characters by the contents of the last executed command for the
6166 shell escape command and
6168 one of the compose mode
6169 .Sx "COMMAND ESCAPES" .
6170 If this variable is not set no reverse solidus stripping is performed.
6173 .It Va batch-exit-on-error
6174 \*(BO If the batch mode has been enabled via the
6176 command line option, then this variable will be consulted whenever \*(UA
6177 completes one operation (returns to the command prompt); if it is set
6178 then \*(UA will terminate if the last operation generated an error.
6182 \*(OP Terminals generate multi-byte sequences for certain forms of
6183 input, for example for function and other special keys.
6184 Some terminals however do not write these multi-byte sequences as
6185 a whole, but byte-by-byte, and the latter is what \*(UA actually reads.
6186 This variable specifies the timeout in milliseconds that the MLE (see
6187 .Sx "On terminal control and line editor" )
6188 waits for more bytes to arrive unless it considers a sequence
6194 \*(BO Causes automatic display of a header summary after executing a
6196 command, and thus complements the standard variable
6198 which controls header summary display on program startup.
6199 It is only meaningful if
6205 \*(BO Sets some cosmetical features to traditional BSD style;
6206 has the same affect as setting
6208 and all other variables prefixed with
6210 it also changes the behaviour of
6212 (which does not exist in BSD).
6216 \*(BO Changes the letters shown in the first column of a header
6217 summary to traditional BSD style.
6221 \*(BO Changes the display of columns in a header summary to traditional
6226 \*(BO Changes some informational messages to traditional BSD style.
6232 field to appear immediately after the
6234 field in message headers and with the
6236 .Sx "COMMAND ESCAPES" .
6240 The value that should appear in the
6244 MIME header fields when no character set conversion of the message data
6246 This defaults to US-ASCII, and the chosen character set should be
6247 US-ASCII compatible.
6251 \*(OP The default 8-bit character set that is used as an implicit last
6252 member of the variable
6254 This defaults to UTF-8.
6255 If no character set conversion capabilities are available in \*(UA then
6256 the only supported character set is
6258 Refer to the section
6259 .Sx "Character sets"
6260 for the complete picture of character set conversion in \*(UA.
6263 .It Va charset-unknown-8bit
6264 \*(OP RFC 1428 specifies conditions when internet mail gateways shall
6266 the content of a mail message by using a character set with the name
6268 Because of the unclassified nature of this character set \*(UA will not
6269 be capable to convert this character set to any other character set.
6270 If this variable is set any message part which uses the character set
6272 is assumed to really be in the character set given in the value,
6273 otherwise the (final) value of
6275 is used for this purpose.
6277 This variable will also be taken into account if a MIME type (see
6278 .Sx "The mime.types files" )
6279 of a MIME message part that uses the
6281 character set is forcefully treated as text.
6285 The default value for the
6290 .It Va colour-disable
6291 \*(BO\*(OP Forcefully disable usage of colours.
6292 Also see the section
6293 .Sx "Coloured display" .
6297 \*(BO\*(OP Whether colour shall be used for output that is paged through
6299 Note that pagers may need special flags, e.g.,
6307 in order to support colours.
6308 Often doing manual adjustments is unnecessary since \*(UA may perform
6309 adjustments dependent on the value of the environment variable
6311 (see there for more).
6315 In a(n interactive) terminal session, then if this valued variable is
6316 set it will be used as a threshold to determine how many lines the given
6317 output has to span before it will be displayed via the configured
6321 can be forced by setting this to the value
6323 setting it without a value will deduce the current height of the
6324 terminal screen to compute the treshold (see
6332 Define a set of custom headers to be injected into newly composed or
6333 forwarded messages; it is also possible to create custom headers in
6336 which can be automated by setting one of the hooks
6337 .Va on-compose-done-shell
6339 .Va on-compose-done .
6340 The value is interpreted as a comma-separated list of custom headers to
6341 be injected, to include commas in the header bodies escape them with
6343 \*(ID Overwriting of automatically managed headers is neither supported
6346 .Dl set customhdr='Hdr1: Body1-1\e, Body1-2, Hdr2: Body2'
6352 the message date, if any is to be displayed according to the format of
6354 is by default taken from the
6356 line of the message.
6357 If this variable is set the date as given in the
6359 header field is used instead, converted to local time.
6360 To control the display format of the date assign a valid
6365 format should not be used, because \*(UA does not take embedded newlines
6366 into account when calculating how many lines fit onto the screen.)
6368 .Va datefield-markout-older .
6371 .It Va datefield-markout-older
6372 This variable, when set in addition to
6376 messages (concept is rather comparable to the
6378 option of the POSIX utility
6380 The content interpretation is identical to
6385 \*(BO Enables debug messages and obsoletion warnings, disables the
6386 actual delivery of messages and also implies
6392 .It Va disposition-notification-send
6394 .Ql Disposition-Notification-To:
6395 header (RFC 3798) with the message.
6399 .\" TODO .It Va disposition-notification-send-HOST
6401 .\".Va disposition-notification-send
6402 .\" for SMTP accounts on a specific host.
6403 .\" TODO .It Va disposition-notification-send-USER@HOST
6405 .\".Va disposition-notification-send
6406 .\"for a specific account.
6410 \*(BO When dot is set, a period
6412 on a line by itself during message input in (interactive) compose mode
6413 will be treated as end-of-message (in addition to the normal end-of-file
6422 .It Va dotlock-ignore-error
6423 \*(BO\*(OP Synchronization of mailboxes which \*(UA treats as system
6424 mailboxes (see the command
6426 will be protected with so-called dotlock files\(emthe traditional mail
6427 spool file locking method\(emin addition to system file locking.
6428 Because \*(UA ships with a privilege-separated dotlock creation program
6429 that should always be able to create such a dotlock file there is no
6430 good reason to ignore dotlock file creation errors, and thus these are
6431 fatal unless this variable is set.
6435 \*(BO If this variable is set then the editor is started automatically
6436 when a message is composed in interactive mode, as if the
6438 .Sx "COMMAND ESCAPES"
6442 variable is implied for this automatically spawned editor session.
6446 \*(BO When a message is edited while being composed,
6447 its header is included in the editable text.
6457 fields are accepted within the header, other fields are ignored.
6461 \*(BO When entering interactive mode \*(UA normally writes
6462 .Dq \&No mail for user
6463 and exits immediately if a mailbox is empty or does not exist.
6464 If this variable is set \*(UA starts even with an empty or nonexistent
6465 mailbox (the latter behaviour furtherly depends upon
6472 .Ql Content-Transfer-Encoding
6473 to use in outgoing text messages and message parts, where applicable.
6474 (7-bit clean text messages are sent as-is, without a transfer encoding.)
6477 .Bl -tag -compact -width "_%%_"
6480 8-bit transport effectively causes the raw data be passed through
6481 unchanged, but may cause problems when transferring mail messages over
6482 channels that are not ESMTP (RFC 1869) compliant.
6483 Also, several input data constructs are not allowed by the
6484 specifications and may cause a different transfer-encoding to be used.
6485 .It Ql quoted-printable
6487 Quoted-printable encoding is 7-bit clean and has the property that ASCII
6488 characters are passed through unchanged, so that an english message can
6489 be read as-is; it is also acceptible for other single-byte locales that
6490 share many characters with ASCII, like, e.g., ISO-8859-1.
6491 The encoding will cause a large overhead for messages in other character
6492 sets: e.g., it will require up to twelve (12) bytes to encode a single
6493 UTF-8 character of four (4) bytes.
6495 .Pf (Or\0 Ql b64 . )
6496 The default encoding, it is 7-bit clean and will always be used for
6498 This encoding has a constant input:output ratio of 3:4, regardless of
6499 the character set of the input data it will encode three bytes of input
6500 to four bytes of output.
6501 This transfer-encoding is not human readable without performing
6507 If defined, the first character of the value of this variable
6508 gives the character to use in place of tilde
6511 .Sx "COMMAND ESCAPES" .
6512 If set to the empty string, command escapes are disabled.
6516 If not set then file and command pipeline targets are not allowed,
6517 and any such address will be filtered out, giving a warning message.
6518 If set without a value then all possible recipient address
6519 specifications will be accepted \(en see the section
6520 .Sx "On sending mail, and non-interactive mode"
6522 To accept them, but only in interactive mode, or when tilde commands
6523 were enabled explicitly by using one of the command line options
6527 set this to the (case-insensitive) value
6529 (note right now this is actually like setting
6530 .Ql restrict,-all,+name,+addr ) .
6532 In fact the value is interpreted as a comma-separated list of values.
6535 then the existence of disallowed specifications is treated as a hard
6536 send error instead of only filtering them out.
6537 The remaining values specify whether a specific type of recipient
6538 address specification is allowed (optionally indicated by a plus sign
6540 prefix) or disallowed (prefixed with a hyphen
6544 addresses all possible address specifications,
6548 command pipeline targets,
6550 plain user names and (MTA) aliases (\*(OB
6552 may be used as an alternative syntax to
6557 These kind of values are interpreted in the given order, so that
6558 .Ql restrict,\:fail,\:+file,\:-all,\:+addr
6559 will cause hard errors for any non-network address recipient address
6560 unless \*(UA is in interactive mode or has been started with the
6564 command line option; in the latter case(s) any address may be used, then.
6568 Unless this variable is set additional
6570 (Mail-Transfer-Agent)
6571 arguments from the command line, as can be given after a
6573 separator, are ignored due to safety reasons.
6574 However, if set to the special (case-insensitive) value
6576 then the presence of additional MTA arguments is treated as a hard
6577 error that causes \*(UA to exit with failure status.
6578 A lesser strict variant is the otherwise identical
6580 which does accept such arguments in interactive mode, or if tilde
6581 commands were enabled explicitly by using one of the command line options
6588 \*(RO String giving a list of features \*(UA, preceded with a plus-sign
6590 if the feature is available, and a minus-sign
6593 The output of the command
6595 will include this information.
6599 \*(BO This setting reverses the meanings of a set of reply commands,
6600 turning the lowercase variants, which by default address all recipients
6601 included in the header of a message
6602 .Pf ( Ic reply , respond , followup )
6603 into the uppercase variants, which by default address the sender only
6604 .Pf ( Ic Reply , Respond , Followup )
6607 .Ic replysender , respondsender , followupsender
6609 .Ic replyall , respondall , followupall
6610 are not affected by the current setting of
6615 .It Va file-hook-load-EXTENSION , file-hook-save-EXTENSION
6616 It is possible to install file hooks which will be used by the
6618 command in order to be able to transparently handle (through an
6619 intermediate temporary file) files with specific
6621 s: the variable values can include shell snippets and are expected to
6622 write data to standard output / read data from standard input,
6624 \*(ID The variables may not be changed while there is a mailbox
6626 .Bd -literal -offset indent
6627 set file-hook-load-xy='echo >&2 XY-LOAD; gzip -cd' \e
6628 file-hook-save-xy='echo >&2 XY-SAVE; gzip -c' \e
6629 record=+null-sent.xy
6634 The default path under which mailboxes are to be saved:
6635 file names that begin with the plus-sign
6637 will be expanded by prefixing them with the value of this variable.
6638 The same special syntax conventions as documented for the
6640 command may be used; if the non-empty value does not start with a solidus
6644 will be prefixed automatically.
6645 If unset or the empty string any
6647 prefixing file names will remain unexpanded.
6651 This variable can be set to the name of a
6653 macro which will be called whenever a
6656 The macro will also be invoked when new mail arrives,
6657 but message lists for commands executed from the macro
6658 only include newly arrived messages then.
6660 are activated by default in a folder hook, causing the covered settings
6661 to be reverted once the folder is left again.
6664 Macro behaviour, including option localization, will change in v15.
6665 Please be aware of that and possibly embed a version check in a resource
6669 .It Va folder-hook-FOLDER
6674 Unlike other folder specifications, the fully expanded name of a folder,
6675 without metacharacters, is used to avoid ambiguities.
6676 However, if the mailbox resides under
6680 specification is tried in addition, e.g., if
6684 (and thus relative to the user's home directory) then
6685 .Pa /home/usr1/mail/sent
6687 .Ql folder-hook-/home/usr1/mail/sent
6688 first, but then followed by
6689 .Ql folder-hook-+sent .
6693 \*(BO Controls whether a
6694 .Ql Mail-Followup-To:
6695 header is generated when sending messages to known mailing lists.
6697 .Va followup-to-honour
6699 .Ic mlist , mlsubscribe , reply
6704 .It Va followup-to-honour
6706 .Ql Mail-Followup-To:
6707 header is honoured when group-replying to a message via
6711 This is a quadoption; if set without a value it defaults to
6721 .It Va forward-as-attachment
6722 \*(BO Original messages are normally sent as inline text with the
6725 and only the first part of a multipart message is included.
6726 With this setting enabled messages are sent as unmodified MIME
6728 attachments with all of their parts included.
6732 The address (or a list of addresses) to put into the
6734 field of the message header, quoting RFC 5322:
6735 the author(s) of the message, that is, the mailbox(es) of the person(s)
6736 or system(s) responsible for the writing of the message.
6739 ing to messages these addresses are handled as if they were in the
6743 If the machine's hostname is not valid at the Internet (for example at
6744 a dialup machine) then either this variable or
6746 (\*(IN and with a defined SMTP protocol in
6749 adds even more fine-tuning capabilities),
6753 contains more than one address,
6756 variable is required (according to the standard RFC 5322).
6758 If a file-based MTA is used, then
6760 (or, if that contains multiple addresses,
6762 can nonetheless be enforced to appear as the envelope sender address at
6763 the MTA protocol level (the RFC 5321 reverse-path), either by using the
6765 command line option (with an empty argument; see there for the complete
6766 picture on this topic), or by setting the internal variable
6767 .Va r-option-implicit .
6771 \*(BO When replying to or forwarding a message \*(UA normally removes
6772 the comment and name parts of email addresses.
6773 If this variable is set such stripping is not performed,
6774 and comments, names etc. are retained.
6778 The string to put before the text of a message with the
6782 .Va forward-as-attachment
6785 .Dq -------- Original Message --------
6786 if unset; No heading is put if it is set to the empty string.
6790 \*(BO Causes the header summary to be written at startup and after
6791 commands that affect the number of messages or the order of messages in
6792 the current folder; enabled by default.
6793 The command line option
6799 complements this and controls header summary display on folder changes.
6804 A format string to use for the summary of
6806 similar to the ones used for
6809 Format specifiers in the given string start with a percent character
6811 and may be followed by an optional decimal number indicating the field
6812 width \(em if that is negative, the field is to be left-aligned.
6813 Valid format specifiers are:
6816 .Bl -tag -compact -width "_%%_"
6818 A plain percent character.
6821 a space character but for the current message
6823 for which it expands to
6827 a space character but for the current message
6829 for which it expands to
6832 \*(OP The spam score of the message, as has been classified via the
6835 Shows only a replacement character if there is no spam support.
6837 Message attribute character (status flag); the actual content can be
6841 The date when the message was received, or the date found in the
6845 variable is set (optionally to a date display format string).
6847 The indenting level in threaded mode.
6849 The address of the message sender.
6851 The message thread tree structure.
6852 (Note that this format does not support a field width.)
6854 The number of lines of the message, if available.
6858 The number of octets (bytes) in the message, if available.
6860 Message subject (if any).
6862 Message subject (if any) in double quotes.
6864 Message recipient flags: is the addressee of the message a known or
6865 subscribed mailing list \(en see
6870 The position in threaded/sorted order.
6874 .Ql %>\&%a\&%m\ %-18f\ %16d\ %4l/%\-5o\ %i%-s ,
6876 .Ql %>\&%a\&%m\ %20-f\ \ %16d\ %3l/%\-5o\ %i%-S
6887 .It Va headline-bidi
6888 Bidirectional text requires special treatment when displaying headers,
6889 because numbers (in dates or for file sizes etc.) will not affect the
6890 current text direction, in effect resulting in ugly line layouts when
6891 arabic or other right-to-left text is to be displayed.
6892 On the other hand only a minority of terminals is capable to correctly
6893 handle direction changes, so that user interaction is necessary for
6895 Note that extended host system support is required nonetheless, e.g.,
6896 detection of the terminal character set is one precondition;
6897 and this feature only works in an Unicode (i.e., UTF-8) locale.
6899 In general setting this variable will cause \*(UA to encapsulate text
6900 fields that may occur when displaying
6902 (and some other fields, like dynamic expansions in
6904 with special Unicode control sequences;
6905 it is possible to fine-tune the terminal support level by assigning
6907 no value (or any value other than
6912 will make \*(UA assume that the terminal is capable to properly deal
6913 with Unicode version 6.3, in which case text is embedded in a pair of
6914 U+2068 (FIRST STRONG ISOLATE) and U+2069 (POP DIRECTIONAL ISOLATE)
6916 In addition no space on the line is reserved for these characters.
6918 Weaker support is chosen by using the value
6920 (Unicode 6.3, but reserve the room of two spaces for writing the control
6921 sequences onto the line).
6926 select Unicode 1.1 support (U+200E, LEFT-TO-RIGHT MARK); the latter
6927 again reserves room for two spaces in addition.
6931 \*(OP If a line editor is available then this can be set to
6932 name the (expandable) path of the location of a permanent history file.
6935 .It Va history-gabby
6936 \*(BO\*(OP Add more entries to the history as is normally done.
6939 .It Va history-gabby-persist
6940 \*(BO\*(OP \*(UA's own MLE will not save the additional
6942 entries in persistent storage unless this variable is set.
6943 On the other hand it will not loose the knowledge of whether
6944 a persistent entry was gabby or not.
6950 \*(OP If a line editor is available this value restricts the
6951 amount of history entries that are saved into a set and valid
6953 A value of less than 0 disables this feature;
6954 note that loading and incorporation of
6956 upon program startup can also be suppressed by doing this.
6957 If unset or 0, a default value will be used.
6958 Dependent on the available line editor this will also define the
6959 number of history entries in memory;
6960 it is also editor-specific whether runtime updates of this value will
6965 \*(BO This setting controls whether messages are held in the system
6967 and it is set by default.
6971 Use this string as hostname when expanding local addresses instead of
6972 the value obtained from
6981 Note that when SMTP transport is not used (via
6983 then it is normally the responsibility of the MTA to create these
6984 fields, \*(IN in conjunction with SMTP however
6986 also influences the results:
6987 you should produce some test messages with the desired combination of
6996 \*(BO\*(OP Can be used to turn off the automatic conversion of domain
6997 names according to the rules of IDNA (internationalized domain names
6999 Since the IDNA code assumes that domain names are specified with the
7001 character set, an UTF-8 locale charset is required to represent all
7002 possible international domain names (before conversion, that is).
7006 \*(BO Ignore interrupt signals from the terminal while entering
7007 messages; instead echo them as
7009 characters and discard the current line.
7013 \*(BO Ignore end-of-file conditions
7014 .Pf ( Ql control-D )
7015 in compose mode on message input and in interactive command input.
7016 If set an interactive command input session can only be left by
7017 explicitly using one of the commands
7021 and message input in compose mode can only be terminated by entering
7024 on a line by itself or by using the
7026 .Sx "COMMAND ESCAPES" ;
7028 overrides a setting of
7033 If this is set to a non-empty string it will be used for expansions of
7038 The value supports a subset of filename expansions itself.
7046 .Sx "COMMAND ESCAPES"
7049 option for indenting messages,
7050 in place of the normal tabulator character
7052 which is the default.
7053 Be sure to quote the value if it contains spaces or tabs.
7057 \*(BO If set, an empty system (MBOX) mailbox file is not removed.
7058 Note that, in conjunction with
7061 .Ev POSIXLY_CORRECT )
7062 any empty file will be removed unless this variable is set.
7063 This may improve the interoperability with other mail user agents
7064 when using a common folder directory, and prevents malicious users
7065 from creating fake mailboxes in a world-writable spool directory.
7066 \*(ID Only local regular (MBOX) files are covered, Maildir or other
7067 mailbox types will never be removed, even if empty.
7070 .It Va keep-content-length
7071 \*(BO When (editing messages and) writing
7073 mailbox files \*(UA can be told to keep the
7077 header fields that some MUAs generate by setting this variable.
7078 Since \*(UA does neither use nor update these non-standardized header
7079 fields (which in itself shows one of their conceptual problems),
7080 stripping them should increase interoperability in between MUAs that
7081 work with with same mailbox files.
7082 Note that, if this is not set but
7083 .Va writebackedited ,
7084 as below, is, a possibly performed automatic stripping of these header
7085 fields already marks the message as being modified.
7089 \*(BO When a message is saved it is usually discarded from the
7090 originating folder when \*(UA is quit.
7091 This setting causes all saved message to be retained.
7094 .It Va line-editor-disable
7095 \*(BO Turn off any enhanced line editing capabilities (see
7096 .Sx "On terminal control and line editor"
7100 .It Va line-editor-no-defaults
7101 \*(BO\*(OP Do not establish any default key binding.
7105 \*(BO When a message is replied to and this variable is set,
7106 it is marked as having been answered.
7107 This mark has no technical meaning in the mail system;
7108 it just causes messages to be marked in the header summary,
7109 and makes them specially addressable.
7113 \*(BO Internal development variable.
7116 .It Va message-id-disable
7117 \*(BO By setting this variable the generation of
7119 can be completely suppressed, effectively leaving this task up to the
7121 (Mail-Transfer-Agent) or the SMTP server.
7122 (According to RFC 5321 your SMTP server is not required to add this
7123 field by itself, so you should ensure that it accepts messages without a
7127 .It Va message-inject-head
7128 A string to put at the beginning of each new message.
7129 The escape sequences tabulator
7136 .It Va message-inject-tail
7137 A string to put at the end of each new message.
7138 The escape sequences tabulator
7146 \*(BO Usually, when an
7148 expansion contains the sender, the sender is removed from the expansion.
7149 Setting this option suppresses these removals.
7154 option to be passed through to the
7156 (Mail-Transfer-Agent); though most of the modern MTAs no longer document
7157 this flag, no MTA is known which does not support it (for historical
7161 .It Va mime-allow-text-controls
7162 \*(BO When sending messages, each part of the message is MIME-inspected
7163 in order to classify the
7166 .Ql Content-Transfer-Encoding:
7169 that is required to send this part over mail transport, i.e.,
7170 a computation rather similar to what the
7172 command produces when used with the
7176 This classification however treats text files which are encoded in
7177 UTF-16 (seen for HTML files) and similar character sets as binary
7178 octet-streams, forcefully changing any
7183 .Ql application/octet-stream :
7184 If that actually happens a yet unset charset MIME parameter is set to
7186 effectively making it impossible for the receiving MUA to automatically
7187 interpret the contents of the part.
7189 If this variable is set, and the data was unambiguously identified as
7190 text data at first glance (by a
7194 file extension), then the original
7196 will not be overwritten.
7199 .It Va mime-alternative-favour-rich
7200 \*(BO If this variable is set then rich MIME alternative parts (e.g.,
7201 HTML) will be preferred in favour of included plain text versions when
7202 displaying messages, provided that a handler exists which produces
7203 output that can be (re)integrated into \*(UA's normal visual display.
7204 (E.g., at the time of this writing some newsletters ship their full
7205 content only in the rich HTML part, whereas the plain text part only
7206 contains topic subjects.)
7209 .It Va mime-counter-evidence
7212 field is used to decide how to handle MIME parts.
7213 Some MUAs however do not use
7215 or a similar mechanism to correctly classify content, but simply specify
7216 .Ql application/octet-stream ,
7217 even for plain text attachments like
7219 If this variable is set then \*(UA will try to classify such MIME
7220 message parts on its own, if possible, for example via a possibly
7221 existing attachment filename.
7222 A non-empty value may also be given, in which case a number is expected,
7223 actually a carrier of bits.
7224 Creating the bit-carrying number is a simple addition:
7225 .Bd -literal -offset indent
7226 ? !echo Value should be set to $((2 + 4 + 8))
7227 Value should be set to 14
7230 .Bl -bullet -compact
7232 If bit two is set (2) then the detected
7234 content-type will be carried along with the message and be used for
7236 .Va pipe-TYPE/SUBTYPE
7237 is responsible for the MIME part, shall that question arise;
7238 when displaying such a MIME part the part-info will indicate the
7239 overridden content-type by showing a plus-sign
7242 If bit three is set (4) then the counter-evidence is always produced
7243 and a positive result will be used as the MIME type, even forcefully
7244 overriding the parts given MIME type.
7246 If bit four is set (8) then as a last resort the actual content of
7247 .Ql application/octet-stream
7248 parts will be inspected, so that data which looks like plain text can be
7253 .It Va mimetypes-load-control
7254 Can be used to control which of the
7256 databases are loaded by \*(UA, as furtherly described in the section
7257 .Sx "The mime.types files" .
7260 is part of the option value, then the user's personal
7262 file will be loaded (if it exists); likewise the letter
7264 controls loading of the system wide
7265 .Pa /etc/mime.types ;
7266 directives found in the user file take precedence, letter matching is
7268 If this variable is not set \*(UA will try to load both files.
7269 Incorporation of the \*(UA-builtin MIME types cannot be suppressed,
7270 but they will be matched last (the order can be listed via
7273 More sources can be specified by using a different syntax: if the
7274 value string contains an equals sign
7276 then it is instead parsed as a comma-separated list of the described
7279 pairs; the given filenames will be expanded and loaded, and their
7280 content may use the extended syntax that is described in the section
7281 .Sx "The mime.types files" .
7282 Directives found in such files always take precedence (are prepended to
7283 the MIME type cache).
7288 To choose an alternate Mail-Transfer-Agent, set this option to either
7289 the full pathname of an executable (optionally prefixed with a
7291 protocol indicator), or \*(OPally a SMTP protocol URL, e.g., \*(IN
7293 .Dl smtps?://[user[:password]@]server[:port]
7296 .Ql [smtp://]server[:port] . )
7297 The default has been chosen at compie time.
7298 All supported data transfers are executed in child processes, which
7299 run asynchronously, and without supervision, unless either the
7304 If such a child receives a TERM signal, it will abort and
7311 For a file-based MTA it may be necessary to set
7313 in in order to choose the right target of a modern
7316 It will be passed command line arguments from several possible sources:
7319 if set, from the command line if given and the variable
7322 Argument processing of the MTA will be terminated with a
7327 The otherwise occurring implicit usage of the following MTA command
7328 line arguments can be disabled by setting the boolean variable
7329 .Va mta-no-default-arguments
7330 (which will also disable passing
7334 (for not treating a line with only a dot
7336 character as the end of input),
7344 variable is set); in conjunction with the
7346 command line option \*(UA will also (not) pass
7352 \*(OP \*(UA can send mail over SMTP network connections to a single
7353 defined SMTP smarthost, the access URL of which has to be assigned to
7355 To use this mode it is helpful to read
7356 .Sx "On URL syntax and credential lookup" .
7357 It may be necessary to set the
7359 variable in order to use a specific combination of
7364 with some mail providers.
7367 .Bl -bullet -compact
7369 The plain SMTP protocol (RFC 5321) that normally lives on the
7370 server port 25 and requires setting the
7371 .Va smtp-use-starttls
7372 variable to enter a SSL/TLS encrypted session state.
7373 Assign a value like \*(IN
7374 .Ql smtp://[user[:password]@]server[:port]
7376 .Ql smtp://server[:port] )
7377 to choose this protocol.
7379 The so-called SMTPS which is supposed to live on server port 465
7380 and is automatically SSL/TLS secured.
7381 Unfortunately it never became a standardized protocol and may thus not
7382 be supported by your hosts network service database
7383 \(en in fact the port number has already been reassigned to other
7386 SMTPS is nonetheless a commonly offered protocol and thus can be
7387 chosen by assigning a value like \*(IN
7388 .Ql smtps://[user[:password]@]server[:port]
7390 .Ql smtps://server[:port] ) ;
7391 due to the mentioned problems it is usually necessary to explicitly
7396 Finally there is the SUBMISSION protocol (RFC 6409), which usually
7397 lives on server port 587 and is practically identically to the SMTP
7398 protocol from \*(UA's point of view beside that; it requires setting the
7399 .Va smtp-use-starttls
7400 variable to enter a SSL/TLS secured session state.
7401 Assign a value like \*(IN
7402 .Ql submission://[user[:password]@]server[:port]
7404 .Ql submission://server[:port] ) .
7409 .It Va mta-arguments
7410 Arguments to pass through to a file-based
7412 can be given via this variable, the content of which will be split up in
7413 a vector of arguments, to be joined onto other possible MTA options:
7415 .Dl set mta-arguments='-t -X \&"/tmp/my log\&"'
7418 .It Va mta-no-default-arguments
7419 \*(BO Unless this variable is set \*(UA will pass some well known
7420 standard command line options to a file-based
7422 (Mail-Transfer-Agent), see there for more.
7426 Many systems use a so-called
7428 environment to ensure compatibility with
7430 This works by inspecting the name that was used to invoke the mail
7432 If this variable is set then the mailwrapper (the program that is
7433 actually executed when calling the file-based
7435 will treat its contents as that name.
7440 .It Va NAIL_EXTRA_RC
7441 The name of an optional startup file to be read last.
7442 This variable has an effect only if it is set in any of the
7443 .Sx "Resource files" ,
7444 it is not imported from the environment.
7445 Use this file for commands that are not understood by other POSIX
7450 .It Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup
7451 \*(BO\*(IN\*(OP Used to control usage of the users
7453 file for lookup of account credentials, as documented in the section
7454 .Sx "On URL syntax and credential lookup"
7458 .Sx "The .netrc file"
7459 documents the file format.
7471 then \*(UA will read the output of a shell pipe instead of the users
7473 file if this variable is set (to the desired shell command).
7474 This can be used to, e.g., store
7478 .Dl set netrc-pipe='gpg -qd ~/.netrc.pgp'
7482 If this variable has the value
7484 newly created local folders will be in Maildir format.
7488 Checks for new mail in the current folder each time the prompt is shown.
7489 A Maildir folder must be re-scanned to determine if new mail has arrived.
7490 If this variable is set to the special value
7492 then a Maildir folder will not be rescanned completely, but only
7493 timestamp changes are detected.
7497 .It Va on-compose-done-shell , on-compose-done
7498 These hooks run once the normal compose mode is finished, but before the
7499 .Va on-compose-leave
7500 macro hook is called, the
7503 Both hooks will be executed in a subprocess, with their input and output
7504 connected to \*(UA such that they can act as if they would be an
7506 The difference in between them is that the former is a
7508 command, whereas the latter is a normal \*(UA macro, but which is
7509 restricted to a small set of commands (the
7513 will indicate the said capability), just enough for the purpose of
7514 controlling the real \*(UA instance sufficiently.
7516 are by default enabled (in the parent) for (the lifetime of) these
7517 hooks, causing covered setting to be forgotten after the message has
7520 During execution of these hook \*(UA will temporarily forget whether it
7521 has been started in interactive mode, (a restricted set of)
7522 .Sx "COMMAND ESCAPES"
7523 will always be available, and for guaranteed reproduceabilities sake
7525 will be set to its default.
7526 The compose mode command
7528 has been especially designed for scriptability (via these hooks).
7529 The first line the hook will read on its standard input is the protocol
7530 version of said command escape, currently
7532 backward incompatible protocol changes are to be expected in the
7533 future, and it is advisable to make use of the protocol version.
7534 \*(ID because most \*(UA commands do not take this new functionality
7535 into account but are ment for human interaction special care must be
7536 taken to avoid deadlocks because of unexpected control flow; i.e., that
7537 both involved processes wait for more input to happen at the same time,
7538 or one doesn't expect more input but the other is stuck waiting for
7539 consumation of its output.
7540 .Bd -literal -offset indent
7541 wysh set on-compose-done-shell=$'\e
7543 printf "hello $version! Headers: ";\e
7544 echo \e'~^header list\e';\e
7545 read status result;\e
7546 echo "status=$status result=$result";\e
7549 set on-compose-done=ocdm
7552 echo version is $ver, escape=$escape
7553 if $features !@ +regex
7554 echoerr 'Need regular-expression support, aborting send'
7557 echo '~^header list'
7560 echoerr 'Failed to read header list, bailing out'
7564 echo '~^header insert cc Diet is your <mirr.or>'
7567 echoerr 'Failed to insert Cc: header, bailing out'
7576 .It Va on-compose-enter , on-compose-leave
7577 Macro hooks which will be executed before compose mode is entered, and
7578 after composing has been finished (but before the
7580 is injected, etc.), respectively.
7582 are by default enabled for these hooks, causing any setting to be
7583 forgotten after the message has been sent.
7584 The following variables will be set temporarily during execution of the
7587 .Bl -tag -compact -width ".It Va compose_subject"
7590 .It Va compose-sender
7592 .It Va compose-to , compose-cc , compose-bcc
7593 The list of receiver addresses as a space-separated list.
7594 .It Va compose-subject
7600 \*(BO Causes the filename given in the
7603 and the sender-based filenames for the
7607 commands to be interpreted relative to the directory given in the
7609 variable rather than to the current directory,
7610 unless it is set to an absolute pathname.
7614 \*(BO If set, each message feed through the command given for
7616 is followed by a formfeed character
7620 .It Va password-USER@HOST , password-HOST , password
7621 \*(IN Variable chain that sets a password, which is used in case none has
7622 been given in the protocol and account-specific URL;
7623 as a last resort \*(UA will ask for a password on the user's terminal if
7624 the authentication method requires a password.
7625 Specifying passwords in a startup file is generally a security risk;
7626 the file should be readable by the invoking user only.
7628 .It Va password-USER@HOST
7629 \*(OU (see the chain above for \*(IN)
7630 Set the password for
7634 If no such variable is defined for a host,
7635 the user will be asked for a password on standard input.
7636 Specifying passwords in a startup file is generally a security risk;
7637 the file should be readable by the invoking user only.
7641 \*(BO Send messages to the
7643 command without performing MIME and character set conversions.
7647 .It Va pipe-TYPE/SUBTYPE
7648 When a MIME message part of type
7650 (case-insensitive) is displayed or quoted,
7651 its text is filtered through the value of this variable interpreted as
7655 forces interpretation of the message part as plain text, e.g.,
7656 .Ql set pipe-application/xml=@
7657 will henceforth display XML
7659 (The same could also be achieved by adding a MIME type marker with the
7662 And \*(OPally MIME type handlers may be defined via
7663 .Sx "The Mailcap files"
7664 \(em corresponding flag strings are shown in parenthesis below.)
7669 can in fact be used to adjust usage and behaviour of a following shell
7670 command specification by appending trigger characters to it, e.g., the
7671 following hypothetical command specification could be used:
7672 .Bd -literal -offset indent
7673 set pipe-X/Y='@*!++=@vim ${NAIL_FILENAME_TEMPORARY}'
7677 .Bl -tag -compact -width ".It Ql __"
7679 Simply by using the special
7681 prefix the MIME type (shell command) handler will only be invoked to
7682 display or convert the MIME part if the message is addressed directly
7683 and alone by itself.
7684 Use this trigger to disable this and always invoke the handler
7685 .Pf ( Cd x-mailx-always ) .
7688 If set the handler will not be invoked when a message is to be quoted,
7689 but only when it will be displayed
7690 .Pf ( Cd x-mailx-noquote ) .
7693 The command will be run asynchronously, i.e., without blocking \*(UA,
7694 which may be a handy way to display a, e.g., PDF file while also
7695 continuing to read the mail message
7696 .Pf ( Cd x-mailx-async ) .
7697 Asynchronous execution implies
7701 The command must be run on an interactive terminal, \*(UA will
7702 temporarily release the terminal to it
7703 .Pf ( Cd needsterminal ) .
7704 This flag is mutual exclusive with
7706 will only be used in interactive mode and implies
7710 Request creation of a zero-sized temporary file, the absolute pathname
7711 of which will be made accessible via the environment variable
7712 .Ev NAIL_FILENAME_TEMPORARY
7713 .Pf ( Cd x-mailx-tmpfile ) .
7714 If this trigger is given twice then the file will be unlinked
7715 automatically by \*(UA when the command loop is entered again at latest
7716 .Pf ( Cd x-mailx-tmpfile-unlink ) .
7717 (Do not use this for asynchronous handlers.)
7720 Normally the MIME part content is passed to the handler via standard
7721 input; if this flag is set then the data will instead be written into
7722 .Ev NAIL_FILENAME_TEMPORARY
7723 .Pf ( Cd x-mailx-tmpfile-fill ) ,
7724 the creation of which is implied; note however that in order to cause
7725 deletion of the temporary file you still have to use two plus signs
7730 To avoid ambiguities with normal shell command content you can use
7731 another at-sign to forcefully terminate interpretation of remaining
7733 (Any character not in this list will have the same effect.)
7737 Some information about the MIME part to be displayed is embedded into
7738 the environment of the shell command:
7741 .Bl -tag -compact -width ".It Ev _AIL__ILENAME__ENERATED"
7744 The MIME content-type of the part, if known, the empty string otherwise.
7747 .It Ev NAIL_CONTENT_EVIDENCE
7749 .Va mime-counter-evidence
7750 includes the carry-around-bit (2), then this will be set to the detected
7751 MIME content-type; not only then identical to
7752 .Ev \&\&NAIL_CONTENT
7756 .It Ev NAIL_FILENAME
7757 The filename, if any is set, the empty string otherwise.
7760 .It Ev NAIL_FILENAME_GENERATED
7764 .It Ev NAIL_FILENAME_TEMPORARY
7765 If temporary file creation has been requested through the command prefix
7766 this variable will be set and contain the absolute pathname of the
7771 The temporary directory that \*(UA uses.
7772 Usually identical to
7774 but guaranteed to be set and usable by child processes;
7775 to ensure the latter condition for
7777 also, it will be set.
7782 .It Va pipe-EXTENSION
7783 This is identical to
7784 .Va pipe-TYPE/SUBTYPE
7787 (normalized to lowercase using character mappings of the ASCII charset)
7788 names a file extension, e.g.,
7790 Handlers registered using this method take precedence.
7793 .It Va pop3-auth-USER@HOST , pop3-auth-HOST , pop3-auth
7794 \*(OP\*(IN Variable chain that sets the POP3 authentication method.
7795 The only possible value as of now is
7797 which is thus the default.
7800 .Mx Va pop3-bulk-load
7801 .It Va pop3-bulk-load-USER@HOST , pop3-bulk-load-HOST , pop3-bulk-load
7802 \*(BO\*(OP When accessing a POP3 server \*(UA loads the headers of
7803 the messages, and only requests the message bodies on user request.
7804 For the POP3 protocol this means that the message headers will be
7806 If this variable is set then \*(UA will download only complete messages
7807 from the given POP3 server(s) instead.
7809 .Mx Va pop3-keepalive
7810 .It Va pop3-keepalive-USER@HOST , pop3-keepalive-HOST , pop3-keepalive
7811 \*(OP POP3 servers close the connection after a period of inactivity;
7812 the standard requires this to be at least 10 minutes,
7813 but practical experience may vary.
7814 Setting this variable to a numeric value greater than
7818 command to be sent each value seconds if no other operation is performed.
7821 .It Va pop3-no-apop-USER@HOST , pop3-no-apop-HOST , pop3-no-apop
7822 \*(BO\*(OP Unless this variable is set the
7824 authentication method will be used when connecting to a POP3 server that
7828 is that the password is not sent in clear text over the wire and that
7829 only a single packet is sent for the user/password tuple.
7831 .Va pop3-no-apop-HOST
7834 .Mx Va pop3-use-starttls
7835 .It Va pop3-use-starttls-USER@HOST , pop3-use-starttls-HOST , pop3-use-starttls
7836 \*(BO\*(OP Causes \*(UA to issue a
7838 command to make an unencrypted POP3 session SSL/TLS encrypted.
7839 This functionality is not supported by all servers,
7840 and is not used if the session is already encrypted by the POP3S method.
7842 .Va pop3-use-starttls-HOST
7847 \*(BO This flag enables POSIX mode, which changes behaviour of \*(UA
7848 where that deviates from standardized behaviour.
7849 It will be set implicitly before the
7850 .Sx "Resource files"
7851 are loaded if the environment variable
7853 is set, and adjusting any of those two will be reflected by the other
7857 .It Va print-alternatives
7858 \*(BO When a MIME message part of type
7859 .Ql multipart/alternative
7860 is displayed and it contains a subpart of type
7862 other parts are normally discarded.
7863 Setting this variable causes all subparts to be displayed,
7864 just as if the surrounding part was of type
7865 .Ql multipart/mixed .
7869 The string used as a prompt in interactive mode.
7870 Whenever the variable is evaluated the value is shell-expanded using
7871 dollar-single-quote expansion mode (see
7873 and it is an error if the prompt expands to more than a single token.
7874 This (post-assignment, i.e., second) expansion can be used to embed
7875 status information, for example
7879 .Va -mailbox-display .
7880 In order to embed characters which should not be counted when
7881 calculating the visual width of the resulting string, enclose the
7882 characters of interest in a pair of reverse solidus escaped brackets:
7884 Prompting may be prevented by setting this to the null string
7886 .Ql set noprompt ) .
7890 This string is used for secondary prompts, but is otherwise identical to
7897 \*(BO Suppresses the printing of the version when first invoked.
7901 If set, \*(UA starts a replying message with the original message
7902 prefixed by the value of the variable
7904 Normally, a heading consisting of
7905 .Dq Fromheaderfield wrote:
7906 is put before the quotation.
7911 variable, this heading is omitted.
7914 is assigned, only the headers selected by the
7917 selection are put above the message body,
7920 acts like an automatic
7922 .Sx "COMMAND ESCAPES"
7926 is assigned, all headers are put above the message body and all MIME
7927 parts are included, making
7929 act like an automatic
7932 .Va quote-as-attachment .
7935 .It Va quote-as-attachment
7936 \*(BO Add the original message in its entirety as a
7938 MIME attachment when replying to a message.
7939 Note this works regardless of the setting of
7944 \*(OP Can be set in addition to
7946 Setting this turns on a more fancy quotation algorithm in that leading
7947 quotation characters are compressed and overlong lines are folded.
7949 can be set to either one or two (space separated) numeric values,
7950 which are interpreted as the maximum (goal) and the minimum line length,
7951 respectively, in a spirit rather equal to the
7953 program, but line-, not paragraph-based.
7954 If not set explicitly the minimum will reflect the goal algorithmically.
7955 The goal cannot be smaller than the length of
7957 plus some additional pad.
7958 Necessary adjustments take place silently.
7961 .It Va r-option-implicit
7962 \*(BO Setting this option evaluates the contents of
7964 (or, if that contains multiple addresses,
7966 and passes the results onto the used (file-based) MTA as described for the
7968 option (empty argument case).
7971 .It Va recipients-in-cc
7972 \*(BO On group replies, specify only the sender of the original mail in
7974 and mention the other recipients in the secondary
7976 By default all recipients of the original mail will be addressed via
7981 If defined, gives the pathname of the folder used to record all outgoing
7983 If not defined, then outgoing mail is not saved.
7984 When saving to this folder fails the message is not sent,
7985 but instead saved to
7989 .It Va record-resent
7990 \*(BO If both this variable and the
7997 commands save messages to the
7999 folder as it is normally only done for newly composed messages.
8002 .It Va reply-in-same-charset
8003 \*(BO If this variable is set \*(UA first tries to use the same
8004 character set of the original message for replies.
8005 If this fails, the mechanism described in
8006 .Sx "Character sets"
8007 is evaluated as usual.
8010 .It Va reply_strings
8011 Can be set to a comma-separated list of (case-insensitive according to
8012 ASCII rules) strings which shall be recognized in addition to the
8015 reply message indicators \(en builtin are
8017 which is mandated by RFC 5322, as well as the german
8022 A list of addresses to put into the
8024 field of the message header.
8025 Members of this list are handled as if they were in the
8030 .It Va reply-to-honour
8033 header is honoured when replying to a message via
8037 This is a quadoption; if set without a value it defaults to
8041 .It Va rfc822-body-from_
8042 \*(BO This variable can be used to force displaying a so-called
8044 line for messages that are embedded into an envelope mail via the
8046 MIME mechanism, for more visual convenience.
8050 \*(BO Enable saving of (partial) messages in
8052 upon interrupt or delivery error.
8056 The number of lines that represents a
8065 line display and scrolling via
8067 If this variable is not set \*(UA falls back to a calculation based upon
8068 the detected terminal window size and the baud rate: the faster the
8069 terminal, the more will be shown.
8070 Overall screen dimensions and pager usage is influenced by the
8071 environment variables
8079 .It Va searchheaders
8080 \*(BO Expand message-list specifiers in the form
8082 to all messages containing the substring
8086 The string search is case insensitive.
8090 \*(OP A comma-separated list of character set names that can be used in
8091 outgoing internet mail.
8092 The value of the variable
8094 is automatically appended to this list of character-sets.
8095 If no character set conversion capabilities are compiled into \*(UA then
8096 the only supported charset is
8099 .Va sendcharsets-else-ttycharset
8100 and refer to the section
8101 .Sx "Character sets"
8102 for the complete picture of character set conversion in \*(UA.
8105 .It Va sendcharsets-else-ttycharset
8106 \*(BO\*(OP If this variable is set, but
8108 is not, then \*(UA acts as if
8110 had been set to the value of the variable
8112 In effect this combination passes through the message data in the
8113 character set of the current locale (given that
8115 has not been set manually), i.e., without converting it to the
8117 fallback character set.
8118 Thus, mail message text will be in ISO-8859-1 encoding when send from
8119 within a ISO-8859-1 locale, and in UTF-8 encoding when send from within
8121 If no character set conversion capabilities are available in \*(UA then
8122 the only supported character set is
8127 An address that is put into the
8129 field of outgoing messages, quoting RFC 5322: the mailbox of the agent
8130 responsible for the actual transmission of the message.
8131 This field should normally not be used unless the
8133 field contains more than one address, on which case it is required.
8136 address is handled as if it were in the
8140 .Va r-option-implicit .
8144 \*(OB Predecessor of
8148 .It Va sendmail-arguments
8149 \*(OB Predecessor of
8153 .It Va sendmail-no-default-arguments
8154 \*(OB\*(BO Predecessor of
8155 .Va mta-no-default-arguments .
8158 .It Va sendmail-progname
8159 \*(OB Predecessor of
8164 \*(BO When sending a message wait until the
8166 (including the builtin SMTP one) exits before accepting further commands.
8168 with this variable set errors reported by the MTA will be recognizable!
8169 If the MTA returns a non-zero exit status,
8170 the exit status of \*(UA will also be non-zero.
8174 \*(BO This setting causes \*(UA to start at the last message
8175 instead of the first one when opening a mail folder.
8179 \*(BO Causes \*(UA to use the sender's real name instead of the plain
8180 address in the header field summary and in message specifications.
8184 \*(BO Causes the recipient of the message to be shown in the header
8185 summary if the message was sent by the user.
8189 The string to expand
8192 .Sx "COMMAND ESCAPES" ) .
8196 The string to expand
8199 .Sx "COMMAND ESCAPES" ) .
8203 Must correspond to the name of a readable file if set.
8204 The file's content is then appended to each singlepart message
8205 and to the first part of each multipart message.
8206 Be warned that there is no possibility to edit the signature for an
8210 .It Va skipemptybody
8211 \*(BO If an outgoing message does not contain any text in its first or
8212 only message part, do not send it but discard it silently (see also the
8218 \*(OP Specifies a directory with CA certificates in PEM (Privacy
8219 Enhanced Mail) format for verification of S/MIME signed messages.
8222 .It Va smime-ca-file
8223 \*(OP Specifies a file with CA certificates in PEM format for
8224 verification of S/MIME signed messages.
8227 .It Va smime-cipher-USER@HOST , smime-cipher
8228 \*(OP Specifies the cipher to use when generating S/MIME encrypted
8229 messages (for the specified account).
8230 RFC 5751 mandates a default of
8233 Possible values are (case-insensitive and) in decreasing cipher strength:
8241 (DES EDE3 CBC, 168 bits; default if
8243 is not available) and
8247 The actually available cipher algorithms depend on the cryptographic
8248 library that \*(UA uses.
8249 \*(OP Support for more cipher algorithms may be available through
8250 dynamic loading via, e.g.,
8251 .Xr EVP_get_cipherbyname 3
8252 (OpenSSL) if \*(UA has been compiled to support this.
8255 .It Va smime-crl-dir
8256 \*(OP Specifies a directory that contains files with CRLs in PEM format
8257 to use when verifying S/MIME messages.
8260 .It Va smime-crl-file
8261 \*(OP Specifies a file that contains a CRL in PEM format to use when
8262 verifying S/MIME messages.
8265 .It Va smime-encrypt-USER@HOST
8266 \*(OP If this variable is set, messages send to the given receiver are
8267 encrypted before sending.
8268 The value of the variable must be set to the name of a file that
8269 contains a certificate in PEM format.
8271 If a message is sent to multiple recipients,
8272 each of them for whom a corresponding variable is set will receive an
8273 individually encrypted message;
8274 other recipients will continue to receive the message in plain text
8276 .Va smime-force-encryption
8278 It is recommended to sign encrypted messages, i.e., to also set the
8283 .It Va smime-force-encryption
8284 \*(BO\*(OP Causes \*(UA to refuse sending unencrypted messages.
8287 .It Va smime-no-default-ca
8288 \*(BO\*(OP Do not load default CA locations when verifying S/MIME
8293 \*(BO\*(OP S/MIME sign outgoing messages with the user's private key
8294 and include the user's certificate as a MIME attachment.
8295 Signing a message enables a recipient to verify that the sender used
8296 a valid certificate,
8297 that the email addresses in the certificate match those in the message
8298 header and that the message content has not been altered.
8299 It does not change the message text,
8300 and people will be able to read the message as usual.
8302 .Va smime-sign-cert , smime-sign-include-certs
8304 .Va smime-sign-message-digest .
8306 .Mx Va smime-sign-cert
8307 .It Va smime-sign-cert-USER@HOST , smime-sign-cert
8308 \*(OP Points to a file in PEM format.
8309 For the purpose of signing and decryption this file needs to contain the
8310 user's private key as well as his certificate.
8314 is always derived from the value of
8316 (or, if that contains multiple addresses,
8318 For the purpose of encryption the recipient's public encryption key
8319 (certificate) is expected; the command
8321 can be used to save certificates of signed messages (the section
8322 .Sx "Signed and encrypted messages with S/MIME"
8323 gives some details).
8324 This mode of operation is usually driven by the specialized form.
8326 When decrypting messages the account is derived from the recipient
8331 of the message, which are searched for addresses for which such
8333 \*(UA always uses the first address that matches,
8334 so if the same message is sent to more than one of the user's addresses
8335 using different encryption keys, decryption might fail.
8337 .Mx Va smime-sign-include-certs
8338 .It Va smime-sign-include-certs-USER@HOST , smime-sign-include-certs
8339 \*(OP If used, this is supposed to a consist of a comma-separated list
8340 of files, each of which containing a single certificate in PEM format to
8341 be included in the S/MIME message in addition to the
8344 This is most useful for long certificate chains if it is desired to aid
8345 the receiving parties verification process.
8346 Note that top level certificates may also be included in the chain but
8347 do not play a role for verification.
8349 .Va smime-sign-cert .
8350 Remember that for this
8352 refers to the variable
8354 (or, if that contains multiple addresses,
8357 .Mx Va smime-sign-message-digest
8358 .It Va smime-sign-message-digest-USER@HOST , smime-sign-message-digest
8359 \*(OP Specifies the message digest to use when signing S/MIME messages.
8360 RFC 5751 mandates a default of
8362 Possible values are (case-insensitive and) in decreasing cipher strength:
8370 The actually available message digest algorithms depend on the
8371 cryptographic library that \*(UA uses.
8372 \*(OP Support for more message digest algorithms may be available
8373 through dynamic loading via, e.g.,
8374 .Xr EVP_get_digestbyname 3
8375 (OpenSSL) if \*(UA has been compiled to support this.
8376 Remember that for this
8378 refers to the variable
8380 (or, if that contains multiple addresses,
8385 \*(OB\*(OP To use the builtin SMTP transport, specify a SMTP URL in
8387 \*(ID For compatibility reasons a set
8389 is used in preference of
8393 .It Va smtp-auth-USER@HOST , smtp-auth-HOST , smtp-auth
8394 \*(OP Variable chain that controls the SMTP
8396 authentication method, possible values are
8402 as well as the \*(OPal methods
8408 method does not need any user credentials,
8410 requires a user name and all other methods require a user name and
8418 .Va smtp-auth-password
8420 .Va smtp-auth-user ) .
8425 .Va smtp-auth-USER@HOST :
8426 may override dependent on sender address in the variable
8429 .It Va smtp-auth-password
8430 \*(OP\*(OU Sets the global fallback password for SMTP authentication.
8431 If the authentication method requires a password, but neither
8432 .Va smtp-auth-password
8434 .Va smtp-auth-password-USER@HOST
8436 \*(UA will ask for a password on the user's terminal.
8438 .It Va smtp-auth-password-USER@HOST
8440 .Va smtp-auth-password
8441 for specific values of sender addresses, dependent upon the variable
8444 .It Va smtp-auth-user
8445 \*(OP\*(OU Sets the global fallback user name for SMTP authentication.
8446 If the authentication method requires a user name, but neither
8449 .Va smtp-auth-user-USER@HOST
8451 \*(UA will ask for a user name on the user's terminal.
8453 .It Va smtp-auth-user-USER@HOST
8456 for specific values of sender addresses, dependent upon the variable
8460 .It Va smtp-hostname
8461 \*(OP\*(IN Normally \*(UA uses the variable
8463 to derive the necessary
8465 information in order to issue a
8472 can be used to use the
8474 from the SMTP account
8481 from the content of this variable (or, if that is the empty string,
8483 or the local hostname as a last resort).
8484 This often allows using an address that is itself valid but hosted by
8485 a provider other than which (in
8487 is about to send the message.
8488 Setting this variable also influences the generated
8491 .Mx Va smtp-use-starttls
8492 .It Va smtp-use-starttls-USER@HOST , smtp-use-starttls-HOST , smtp-use-starttls
8493 \*(BO\*(OP Causes \*(UA to issue a
8495 command to make an SMTP
8497 session SSL/TLS encrypted, i.e., to enable transport layer security.
8501 .It Va spam-interface
8502 \*(OP In order to use any of the spam-related commands (like, e.g.,
8504 the desired spam interface must be defined by setting this variable.
8505 Please refer to the manual section
8507 for the complete picture of spam handling in \*(UA.
8508 All or none of the following interfaces may be available:
8510 .Bl -tag -width ".It Ql _ilte_"
8516 .Pf ( Lk http://spamassassin.apache.org SpamAssassin )
8518 Different to the generic filter interface \*(UA will automatically add
8519 the correct arguments for a given command and has the necessary
8520 knowledge to parse the program's output.
8523 will have been compiled into the \*(UA binary if
8528 Shall it be necessary to define a specific connection type (rather than
8529 using a configuration file for that), the variable
8531 can be used as in, e.g.,
8532 .Ql -d server.example.com -p 783 .
8533 It is also possible to specify a per-user configuration via
8535 Note that this interface does not inspect the
8537 flag of a message for the command
8541 generic spam filter support via freely configurable hooks.
8542 This interface is meant for programs like
8544 and requires according behaviour in respect to the hooks' exit
8545 status for at least the command
8548 meaning a message is spam,
8552 for unsure and any other return value indicating a hard error);
8553 since the hooks can include shell code snippets diverting behaviour
8554 can be intercepted as necessary.
8556 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
8559 .Va spamfilter-spam ;
8562 contains examples for some programs.
8563 The process environment of the hooks will have the variables
8564 .Ev NAIL_TMPDIR , TMPDIR
8566 .Ev NAIL_FILENAME_GENERATED
8568 Note that spam score support for
8570 is not supported unless the \*(OPtional regular expression support is
8572 .Va spamfilter-rate-scanscore
8579 \*(OP Messages that exceed this size will not be passed through to the
8581 .Va spam-interface .
8582 If unset or 0, the default of 420000 bytes is used.
8585 .It Va spamc-command
8586 \*(OP The path to the
8590 .Va spam-interface .
8591 Note that the path is not expanded, but used
8593 A fallback path will have been compiled into the \*(UA binary if the
8594 executable had been found during compilation.
8597 .It Va spamc-arguments
8598 \*(OP Even though \*(UA deals with most arguments for the
8601 automatically, it may at least sometimes be desirable to specify
8602 connection-related ones via this variable, e.g.,
8603 .Ql -d server.example.com -p 783 .
8607 \*(OP Specify a username for per-user configuration files for the
8609 .Va spam-interface .
8610 If this is set to the empty string then \*(UA will use the name of the
8619 .It Va spamfilter-ham , spamfilter-noham , \
8620 spamfilter-nospam , spamfilter-rate , spamfilter-spam
8621 \*(OP Command and argument hooks for the
8623 .Va spam-interface .
8626 contains examples for some programs.
8629 .It Va spamfilter-rate-scanscore
8630 \*(OP Because of the generic nature of the
8633 spam scores are not supported for it by default, but if the \*(OPtional
8634 regular expression support is available then setting this variable can
8635 be used to overcome this restriction.
8636 It is interpreted as follows: first a number (digits) is parsed that
8637 must be followed by a semicolon
8639 and an extended regular expression.
8640 Then the latter is used to parse the first output line of the
8642 hook, and, in case the evaluation is successful, the group that has been
8643 specified via the number is interpreted as a floating point scan score.
8647 \*(OP Specifies a directory with CA certificates in PEM (Pricacy
8648 Enhanced Mail) for verification of of SSL/TLS server certificates.
8650 .Xr SSL_CTX_load_verify_locations 3
8651 for more information.
8655 \*(OP Specifies a file with CA certificates in PEM format for
8656 verification of SSL/TLS server certificates.
8658 .Xr SSL_CTX_load_verify_locations 3
8659 for more information.
8662 .It Va ssl-cert-USER@HOST , ssl-cert-HOST , ssl-cert
8663 \*(OP Variable chain that sets the file name for a SSL/TLS client
8664 certificate required by some servers.
8665 This is a direct interface to the
8669 function of the OpenSSL library, if available.
8671 .Mx Va ssl-cipher-list
8672 .It Va ssl-cipher-list-USER@HOST , ssl-cipher-list-HOST , ssl-cipher-list
8673 \*(OP Specifies a list of ciphers for SSL/TLS connections.
8674 This is a direct interface to the
8678 function of the OpenSSL library, if available; see
8680 for more information.
8681 By default \*(UA does not set a list of ciphers, in effect using a
8683 specific cipher (protocol standards ship with a list of acceptable
8684 ciphers), possibly cramped to what the actually used SSL/TLS library
8685 supports \(en the manual section
8686 .Sx "An example configuration"
8687 also contains a SSL/TLS use case.
8690 .It Va ssl-config-file
8691 \*(OP If this variable is set \*(UA will call
8692 .Xr CONF_modules_load_file 3
8693 to allow OpenSSL to be configured according to the host system wide
8695 If a non-empty value is given then this will be used to specify the
8696 configuration file to be used instead of the global OpenSSL default;
8697 note that in this case it is an error if the file cannot be loaded.
8698 The application name will always be passed as
8703 \*(OP Specifies a file that contains a CRL in PEM format to use when
8704 verifying SSL/TLS server certificates.
8708 \*(OP Specifies a directory that contains files with CRLs in PEM format
8709 to use when verifying SSL/TLS server certificates.
8712 .It Va ssl-key-USER@HOST , ssl-key-HOST , ssl-key
8713 \*(OP Variable chain that sets the file name for the private key of
8714 a SSL/TLS client certificate.
8715 If unset, the name of the certificate file is used.
8716 The file is expected to be in PEM format.
8717 This is a direct interface to the
8721 function of the OpenSSL library, if available.
8724 .It Va ssl-method-USER@HOST , ssl-method-HOST , ssl-method
8725 \*(OB\*(OP Please use the newer and more flexible
8727 instead: if both values are set,
8729 will take precedence!
8730 Can be set to the following values, the actually used
8732 specification to which it is mapped is shown in parenthesis:
8734 .Pf ( Ql -ALL, TLSv1.2 ) ,
8736 .Pf ( Ql -ALL, TLSv1.1 ) ,
8738 .Pf ( Ql -ALL, TLSv1 )
8741 .Pf ( Ql -ALL, SSLv3 ) ;
8746 and thus includes the SSLv3 protocol.
8747 Note that SSLv2 is no longer supported at all.
8750 .It Va ssl-no-default-ca
8751 \*(BO\*(OP Do not load default CA locations to verify SSL/TLS server
8755 .It Va ssl-protocol-USER@HOST , ssl-protocol-HOST , ssl-protocol
8756 \*(OP Specify the used SSL/TLS protocol.
8757 This is a direct interface to the
8761 function of the OpenSSL library, if available;
8762 otherwise an \*(UA internal parser is used which understands the
8763 following subset of (case-insensitive) command strings:
8769 as well as the special value
8771 Multiple specifications may be given via a comma-separated list which
8772 ignores any whitespace.
8775 plus prefix will enable a protocol, a
8777 minus prefix will disable it, so that
8779 will enable only the TLSv1.2 protocol.
8781 It depends upon the used TLS/SSL library which protocols are actually
8782 supported and which protocols are used if
8784 is not set, but note that SSLv2 is no longer supported at all and
8786 Especially for older protocols explicitly securing
8788 may be worthwile, see
8789 .Sx "An example configuration" .
8793 \*(OP Gives the pathname to an entropy daemon socket, see
8795 Not all SSL/TLS libraries support this.
8798 .It Va ssl-rand-file
8799 \*(OP Gives the filename to a file with random entropy data, see
8800 .Xr RAND_load_file 3 .
8801 If this variable is not set, or set to the empty string, or if the
8802 filename expansion failed, then
8803 .Xr RAND_file_name 3
8804 will be used to create the filename if, and only if,
8806 documents that the SSL PRNG is not yet sufficiently seeded.
8807 If \*(UA successfully seeded the SSL PRNG then it will update the file
8808 .Pf ( Xr RAND_write_file 3 ) .
8809 This variable is only used if
8811 is not set (or not supported by the SSL/TLS library).
8814 .It Va ssl-verify-USER@HOST , ssl-verify-HOST , ssl-verify
8815 \*(OP Variable chain that sets the action to be performed if an error
8816 occurs during SSL/TLS server certificate validation.
8817 Valid (case-insensitive) values are
8819 (fail and close connection immediately),
8821 (ask whether to continue on standard input),
8823 (show a warning and continue),
8825 (do not perform validation).
8831 If only set without an assigned value, then this setting inhibits the
8836 header fields that include obvious references to \*(UA.
8837 There are two pitfalls associated with this:
8838 First, the message id of outgoing messages is not known anymore.
8839 Second, an expert may still use the remaining information in the header
8840 to track down the originating mail user agent.
8845 suppression does not occur.
8850 (\*(OP) This specifies a comma-separated list of
8855 .Sx "On terminal control and line editor" ,
8856 escape commas with reverse solidus) to be used to overwrite or define
8858 Note that this variable will only be queried once at program startup and
8859 can thus only be specified in resource files or on the command line.
8862 String capabilities form
8864 pairs and are expected unless noted otherwise.
8865 Numerics have to be notated as
8867 where the number is expected in normal decimal notation.
8868 Finally, booleans do not have any value but indicate a true or false
8869 state simply by being defined or not; this indeed means that \*(UA
8870 does not support undefining an existing boolean.
8871 String capability values will undergo some expansions before use:
8872 for one notations like
8875 .Ql control-LETTER ,
8876 and for clarification purposes
8878 can be used to specify
8880 (the control notation
8882 could lead to misreadings when a left bracket follows, which it does for
8883 the standard CSI sequence);
8884 finally three letter octal sequences, as in
8887 To specify that a terminal supports 256-colours, and to define sequences
8888 that home the cursor and produce an audible bell, one might write:
8890 .Bd -literal -offset indent
8891 set termcap='Co#256,home=\eE[H,bel=^G'
8895 The following terminal capabilities are or may be meaningful for the
8896 operation of the builtin line editor or \*(UA in general:
8899 .Bl -tag -compact -width yay
8901 .It Cd colors Ns \0or Cd Co
8903 numeric capability specifying the maximum number of colours.
8904 Note that \*(UA does not actually care about the terminal beside that,
8905 but always emits ANSI / ISO 6429 escape sequences.
8908 .It Cd rmcup Ns \0or Cd te Ns \0/ Cd smcup Ns \0or Cd ti
8912 respectively: exit and enter the alternative screen
8914 effectively turning \*(UA into a fullscreen application.
8915 To disable that, set (at least) one to the empty string.
8917 .It Cd smkx Ns \0or Cd ks Ns \0/ Cd rmkx Ns \0or Cd ke
8921 respectively: enable and disable the keypad.
8922 This is always enabled if available, because it seems even keyboards
8923 without keypads generate other key codes for, e.g., cursor keys in that
8924 case, and only if enabled we see the codes that we are interested in.
8926 .It Cd ed Ns \0or Cd cd
8930 .It Cd clear Ns \0or Cd cl
8932 clear the screen and home cursor.
8933 (Will be simulated via
8938 .It Cd home Ns \0or Cd ho
8943 .It Cd el Ns \0or Cd ce
8945 clear to the end of line.
8946 (Will be simulated via
8948 plus repetitions of space characters.)
8950 .It Cd hpa Ns \0or Cd ch
8951 .Cd column_address :
8952 move the cursor (to the given column parameter) in the current row.
8953 (Will be simulated via
8959 .Cd carriage_return :
8960 move to the first column in the current row.
8961 The default builtin fallback is
8964 .It Cd cub1 Ns \0or Cd le
8966 move the cursor left one space (non-destructively).
8967 The default builtin fallback is
8970 .It Cd cuf1 Ns \0or Cd nd
8972 move the cursor right one space (non-destructively).
8973 The default builtin fallback is
8975 which is used by most terminals.
8983 Many more capabilities which describe key-sequences are documented for
8987 .It Va termcap-disable
8988 \*(OP Disable any interaction with a terminal control library.
8989 If set only some generic fallback builtins and possibly the content of
8991 describe the terminal to \*(UA.
8993 that this variable will only be queried once at program startup and can
8994 thus only be specified in resource files or on the command line.
8998 If defined, gives the number of lines of a message to be displayed
9001 if unset, the first five lines are printed, if set to 0 the variable
9004 If the value is negative then its absolute value will be used for right
9007 height; (shifting bitwise is like dividing algorithmically, but since
9008 it takes away bits the value decreases pretty fast).
9012 \*(BO If set then the
9014 command series will strip adjacent empty lines and quotations.
9018 The character set of the terminal \*(UA operates on,
9019 and the one and only supported character set that \*(UA can use if no
9020 character set conversion capabilities have been compiled into it,
9021 in which case it defaults to ISO-8859-1 unless it can deduce a value
9025 Refer to the section
9026 .Sx "Character sets"
9027 for the complete picture about character sets.
9030 .It Va typescript-mode
9031 \*(BO A special multiplex variable that disables all variables and
9032 settings which result in behaviour that interferes with running \*(UA in
9035 .Va colour-disable ,
9036 .Va line-editor-disable
9037 and (before startup completed only)
9038 .Va termcap-disable .
9039 Unsetting it does not restore the former state of the covered settings.
9043 For a safety-by-default policy \*(UA sets its process
9047 but this variable can be used to override that:
9048 set it to an empty value to do not change the (current) setting,
9049 otherwise the process file mode creation mask is updated to the new value.
9050 Child processes inherit the process file mode creation mask.
9053 .It Va user-HOST , user
9054 \*(IN Variable chain that sets a global fallback user name, which is
9055 used in case none has been given in the protocol and account-specific
9057 This variable defaults to the name of the user who runs \*(UA.
9061 \*(BO Setting this enables upward compatibility with \*(UA
9062 version 15.0 in respect to which configuration options are available and
9063 how they are handled.
9064 This manual uses \*(IN and \*(OU to refer to the new and the old way of
9065 doing things, respectively.
9069 \*(BO This setting, also controllable via the command line option
9071 causes \*(UA to be more verbose, e.g., it will display obsoletion
9072 warnings and SSL/TLS certificate chains.
9073 Even though marked \*(BO this option may be set twice in order to
9074 increase the level of verbosity even more, in which case even details of
9075 the actual message delivery and protocol conversations are shown.
9078 is sufficient to disable verbosity as such.
9084 .It Va version , version-major , version-minor , version-update
9085 \*(RO \*(UA version information: the first variable contains a string
9086 containing the complete version identification, the latter three contain
9087 only digits: the major, minor and update version numbers.
9088 The output of the command
9090 will include this information.
9093 .It Va writebackedited
9094 If this variable is set messages modified using the
9098 commands are written back to the current folder when it is quit;
9099 it is only honoured for writable folders in MBOX format, though.
9100 Note that the editor will be pointed to the raw message content in that
9101 case, i.e., neither MIME decoding nor decryption will have been
9102 performed, and proper RFC 4155
9104 quoting of newly added or edited content is also left as an excercise to
9108 .\" }}} (INTERNAL VARIABLES)
9111 .\" .Sh ENVIRONMENT {{{
9115 .Dq environment variable
9116 should be considered an indication that these variables are either
9117 standardized as vivid parts of process environments, or that they are
9118 commonly found in there.
9119 The process environment is inherited from the
9121 once \*(UA is started, and unless otherwise explicitly noted handling of
9122 the following variables transparently integrates into that of the
9123 .Sx "INTERNAL VARIABLES"
9124 from \*(UA's point of view.
9125 This means that, e.g., they can be managed via
9129 causing automatic program environment updates (to be inherited by
9130 newly created child processes).
9133 In order to transparently integrate other environment variables equally
9134 they need to be imported (linked) with the command
9136 This command can also be used to set and unset non-integrated
9137 environment variables from scratch, sufficient system support provided.
9138 The following example, applicable to a POSIX shell, sets the
9140 environment variable for \*(UA only, and beforehand exports the
9142 in order to affect any further processing in the running shell:
9144 .Bd -literal -offset indent
9145 $ EDITOR="vim -u ${HOME}/.vimrc"
9147 $ COLUMNS=80 \*(uA -R
9150 .Bl -tag -width ".It Ev _AILR_"
9153 The user's preferred width in column positions for the terminal screen
9155 Queried and used once on program startup, actively managed for child
9156 processes and the MLE (see
9157 .Sx "On terminal control and line editor" )
9158 in interactive mode thereafter.
9162 The name of the (mailbox)
9164 to use for saving aborted messages if
9166 is set; this defaults to
9173 is set no output will be generated, otherwise the contents of the file
9178 Pathname of the text editor to use in the
9182 .Sx "COMMAND ESCAPES" .
9183 A default editor is used if this value is not defined.
9187 The user's home directory.
9188 This variable is only used when it resides in the process environment.
9195 .It Ev LANG , LC_ALL , LC_COLLATE , LC_CTYPE , LC_MESSAGES
9199 .Sx "Character sets" .
9203 The user's preferred number of lines on a page or the vertical screen
9204 or window size in lines.
9205 Queried and used once on program startup, actively managed for child
9206 processes in interactive mode thereafter.
9210 Pathname of the directory lister to use in the
9212 command when operating on local mailboxes.
9215 (path search through
9220 Upon startup \*(UA will actively ensure that this variable refers to the
9221 name of the user who runs \*(UA, in order to be able to pass a verified
9222 name to any newly created child process.
9226 Is used as the user's primary system mailbox, unless
9230 This is assumed to be an absolute pathname.
9234 \*(OP Overrides the default path search for
9235 .Sx "The Mailcap files" ,
9236 which is defined in the standard RFC 1524 as
9237 .Ql ~/.mailcap:\:/etc/mailcap:\:/usr/etc/mailcap:\:/usr/local/etc/mailcap .
9238 .\" TODO we should have a mailcaps-default virtual RDONLY option!
9239 (\*(UA makes it a configuration option, however.)
9240 Note this is not a search path, but a path search.
9244 Is used as a startup file instead of
9247 When \*(UA scripts are invoked on behalf of other users,
9248 either this variable should be set to
9252 command line option should be used in order to avoid side-effects from
9253 reading their configuration files.
9254 This variable is only used when it resides in the process environment.
9258 The name of the user's mbox file.
9259 A logical subset of the special conventions that are documented for the
9261 command and the internal variable
9264 The fallback default is
9269 Traditionally this secondary mailbox is used as the file to save
9270 messages from the primary system mailbox that have been read.
9272 .Sx "Message states" .
9275 .It Ev NAIL_NO_SYSTEM_RC
9276 If this variable is set then reading of
9278 at startup is inhibited, i.e., the same effect is achieved as if \*(UA
9279 had been started up with the option
9281 This variable is only used when it resides in the process environment.
9285 \*(IN\*(OP This variable overrides the default location of the user's
9291 Pathname of the program to use for backing the command
9295 variable enforces usage of a pager for output.
9296 The default paginator is
9298 (path search through
9301 \*(UA inspects the contents of this variable: if its contains the string
9303 then a non-existing environment variable
9310 dependent on whether terminal control support is available and whether
9311 that supports full (alternative) screen mode or not (also see
9312 .Sx "On terminal control and line editor" ) .
9316 will optionally be set to
9323 A colon-separated list of directories that is searched by the shell when
9324 looking for commands, e.g.,
9325 .Ql /bin:/usr/bin:/usr/local/bin .
9328 .It Ev POSIXLY_CORRECT
9329 This variable is automatically looked for upon startup, see
9335 The shell to use for the commands
9340 .Sx "COMMAND ESCAPES"
9341 and when starting subprocesses.
9342 A default shell is used if this environment variable is not defined.
9345 .It Ev SOURCE_DATE_EPOCH
9346 If set, this specifies a time in seconds since the Unix epoch
9347 (1970-01-01) to be used in place of the current time.
9348 This is for the sake of reproduceability of tests, to be used during
9349 development or by software packagers.
9353 \*(OP The terminal type for which output is to be prepared.
9354 For extended colour and font control please refer to
9355 .Sx "Coloured display" ,
9356 and for terminal management in general to
9357 .Sx "On terminal control and line editor" .
9361 Used as directory for temporary files instead of
9364 This variable is only used when it resides in the process environment.
9370 (see there), but this variable is not standardized, should therefore not
9371 be used, and is only corrected if already set.
9375 Pathname of the text editor to use in the
9379 .Sx "COMMAND ESCAPES" .
9387 .Bl -tag -width ".It Pa _etc/mime.type_"
9389 File giving initial commands.
9392 System wide initialization file.
9396 \*(OP Personal MIME type handler definition file, see
9397 .Sx "The Mailcap files" .
9398 (RFC 1524 location, the actual path is a configuration option.)
9402 \*(OP System wide MIME type handler definition file, see
9403 .Sx "The Mailcap files" .
9404 (RFC 1524 location, the actual path is a configuration option.)
9407 .It Pa ~/.mime.types
9408 Personal MIME types, see
9409 .Sx "The mime.types files" .
9412 .It Pa /etc/mime.types
9413 System wide MIME types, see
9414 .Sx "The mime.types files" .
9418 \*(IN\*(OP The default location of the users
9420 file \(en the section
9421 .Sx "The .netrc file"
9422 documents the file format.
9425 .\" .Ss "The mime.types files" {{{
9426 .Ss "The mime.types files"
9428 When sending messages \*(UA tries to determine the content type of all
9430 When displaying message content or attachments \*(UA uses the content
9431 type to decide whether it can directly display data or whether it needs
9432 to deal with content handlers.
9433 It learns about M(ultipurpose) I(nternet) M(ail) E(xtensions) types and
9434 how to treat them by reading
9436 files, the loading of which can be controlled by setting the variable
9437 .Va mimetypes-load-control .
9440 can also be used to deal with MIME types.)
9442 files have the following syntax:
9445 .Dl type/subtype extension [extension ...]
9450 are strings describing the file contents, and one or multiple
9452 s, separated by whitespace, name the part of a filename starting after
9453 the last dot (of interest).
9454 Comments may be introduced anywhere on a line with a number sign
9456 causing the remaining line to be discarded.
9458 \*(UA also supports an extended, non-portable syntax in specially
9459 crafted files, which can be loaded via the alternative value syntax of
9460 .Va mimetypes-load-control
9461 and prepends an optional
9465 .Dl [type-marker ]type/subtype extension [extension ...]
9468 The following type markers are supported:
9471 .Bl -tag -compact -width ".It Ar _n_u"
9473 Treat message parts with this content as plain text.
9478 Treat message parts with this content as HTML tagsoup.
9479 If the \*(OPal HTML-tagsoup-to-text converter is not available treat
9480 the content as plain text instead.
9484 but instead of falling back to plain text require an explicit content
9485 handler to be defined.
9490 for sending messages:
9492 .Va mime-allow-text-controls ,
9493 .Va mimetypes-load-control .
9494 For reading etc. messages:
9495 .Sx "HTML mail and MIME attachments" ,
9496 .Sx "The Mailcap files" ,
9498 .Va mime-counter-evidence ,
9499 .Va mimetypes-load-control ,
9500 .Va pipe-TYPE/SUBTYPE ,
9501 .Va pipe-EXTENSION .
9504 .\" .Ss "The Mailcap files" {{{
9505 .Ss "The Mailcap files"
9508 .Dq User Agent Configuration Mechanism
9509 which \*(UA \*(OPally supports.
9510 It defines a file format to be used to inform mail user agent programs
9511 about the locally-installed facilities for handling various data
9512 formats, i.e., about commands and how they can be used to display, edit
9513 etc. MIME part contents, as well as a default path search that includes
9514 multiple possible locations of
9518 environment variable that can be used to overwrite that (repeating here
9519 that it is not a search path, but instead a path search specification).
9520 Any existing files will be loaded in sequence, appending any content to
9521 the list of MIME type handler directives.
9525 files consist of a set of newline separated entries.
9526 Comment lines start with a number sign
9528 (in the first column!) and are ignored.
9529 Empty lines are also ignored.
9530 All other lines form individual entries that must adhere to the syntax
9532 To extend a single entry (not comment) its line can be continued on
9533 follow lines if newline characters are
9535 by preceding them with the reverse solidus character
9537 The standard does not specify how leading whitespace of follow lines
9538 is to be treated, therefore \*(UA retains it.
9542 entries consist of a number of semicolon
9544 separated fields, and the reverse solidus
9546 character can be used to escape any following character including
9547 semicolon and itself.
9548 The first two fields are mandatory and must occur in the specified
9549 order, the remaining fields are optional and may appear in any order.
9550 Leading and trailing whitespace of content is ignored (removed).
9553 The first field defines the MIME
9555 the entry is about to handle (case-insensitively, and no reverse solidus
9556 escaping is possible in this field).
9557 If the subtype is specified as an asterisk
9559 the entry is meant to match all subtypes of the named type, e.g.,
9561 would match any audio type.
9562 The second field defines the shell command which shall be used to
9564 MIME parts of the given type; it is implicitly called the
9571 shell commands message (MIME part) data is passed via standard input
9572 unless the given shell command includes one or more instances of the
9575 in which case these instances will be replaced with a temporary filename
9576 and the data will have been stored in the file that is being pointed to.
9579 shell commands data is assumed to be generated on standard output unless
9580 the given command includes (one ore multiple)
9582 In any case any given
9584 format is replaced with a(n already) properly quoted filename.
9585 Note that when a command makes use of a temporary file via
9587 then \*(UA will remove it again, as if the
9588 .Cd x-mailx-tmpfile ,
9589 .Cd x-mailx-tmpfile-fill
9591 .Cd x-mailx-tmpfile-unlink
9592 flags had been set; see below for more.
9595 The optional fields either define a shell command or an attribute (flag)
9596 value, the latter being a single word and the former being a keyword
9597 naming the field followed by an equals sign
9599 succeeded by a shell command, and as usual for any
9601 content any whitespace surrounding the equals sign will be removed, too.
9602 Optional fields include the following:
9605 .Bl -tag -width textualnewlines
9607 A program that can be used to compose a new body or body part in the
9614 field, but is to be used when the composing program needs to specify the
9616 header field to be applied to the composed data.
9620 A program that can be used to edit a body or body part in the given
9625 A program that can be used to print a message or body part in the given
9630 Specifies a program to be run to test some condition, e.g., the machine
9631 architecture, or the window system in use, to determine whether or not
9632 this mailcap entry applies.
9633 If the test fails, a subsequent mailcap entry should be sought; also see
9634 .Cd x-mailx-test-once .
9636 .It Cd needsterminal
9637 This flag field indicates that the given shell command must be run on
9638 an interactive terminal.
9639 \*(UA will temporarily release the terminal to the given command in
9640 interactive mode, in non-interactive mode this entry will be entirely
9641 ignored; this flag implies
9642 .Cd x-mailx-noquote .
9644 .It Cd copiousoutput
9645 A flag field which indicates that the output of the
9647 command will be an extended stream of textual output that can be
9648 (re)integrated into \*(UA's normal visual display.
9649 It is mutually exclusive with
9652 .Cd x-mailx-always .
9654 .It Cd textualnewlines
9655 A flag field which indicates that this type of data is line-oriented and
9658 all newlines should be converted to canonical form (CRLF) before
9659 encoding, and will be in that form after decoding.
9663 This field gives a file name format, in which
9665 will be replaced by a random string, the joined combination of which
9666 will be used as the filename denoted by
9667 .Ev NAIL_FILENAME_TEMPORARY .
9668 One could specify that a GIF file being passed to an image viewer should
9669 have a name ending in
9672 .Ql nametemplate=%s.gif .
9673 Note that \*(UA ignores the name template unless that solely specifies
9674 a filename suffix that consists of (ASCII) alphabetic and numeric
9675 characters, the underscore and dot only.
9678 Names a file, in X11 bitmap (xbm) format, which points to an appropriate
9679 icon to be used to visually denote the presence of this kind of data.
9680 This field is not used by \*(UA.
9683 A textual description that describes this type of data.
9685 .It Cd x-mailx-always
9686 Extension flag field that denotes that the given
9688 command shall be executed even if multiple messages will be displayed
9690 Normally messages which require external viewers that produce output
9691 which does not integrate into \*(UA's visual display (i.e., do not have
9693 set) have to be addressed directly and individually.
9694 (To avoid cases where, e.g., a thousand PDF viewer instances are spawned
9697 .It Cd x-mailx-even-if-not-interactive
9698 An extension flag test field \(em by default handlers without
9700 are entirely ignored in non-interactive mode, but if this flag is set
9701 then their use will be considered.
9702 It is an error if this flag is set for commands that use the flag
9705 .It Cd x-mailx-noquote
9706 An extension flag field that indicates that even a
9709 command shall not be used to generate message quotes
9710 (as it would be by default).
9712 .It Cd x-mailx-async
9713 Extension flag field that denotes that the given
9715 command shall be executed asynchronously, without blocking \*(UA.
9716 Cannot be used in conjunction with
9719 .It Cd x-mailx-test-once
9720 Extension flag which denotes whether the given
9722 command shall be evaluated once only and the (boolean) result be cached.
9723 This is handy if some global unchanging condition is to be queried, like
9724 .Dq running under the X Window System .
9726 .It Cd x-mailx-tmpfile
9727 Extension flag field that requests creation of a zero-sized temporary
9728 file, the name of which is to be placed in the environment variable
9729 .Ev NAIL_FILENAME_TEMPORARY .
9730 It is an error to use this flag with commands that include a
9734 .It Cd x-mailx-tmpfile-fill
9735 Normally the MIME part content is passed to the handler via standard
9736 input; if this flag is set then the data will instead be written into
9738 .Cd x-mailx-tmpfile .
9739 In order to cause deletion of the temporary file you will have to set
9740 .Cd x-mailx-tmpfile-unlink
9742 It is an error to use this flag with commands that include a
9746 .It Cd x-mailx-tmpfile-unlink
9747 Extension flag field that requests that the temporary file shall be
9748 deleted automatically when the command loop is entered again at latest.
9749 (Do not use this for asynchronous handlers.)
9750 It is an error to use this flag with commands that include a
9752 format, or without also setting
9755 .Cd x-mailx-tmpfile-fill .
9757 .It Cd x-mailx-tmpfile-keep
9760 implies the three tmpfile related flags above, but if you want, e.g.,
9762 and deal with the temporary file yourself, you can add in this flag to
9764 .Cd x-mailx-tmpfile-unlink .
9769 The standard includes the possibility to define any number of additional
9770 entry fields, prefixed by
9772 Flag fields apply to the entire
9774 entry \(em in some unusual cases, this may not be desirable, but
9775 differentiation can be accomplished via separate entries, taking
9776 advantage of the fact that subsequent entries are searched if an earlier
9777 one does not provide enough information.
9780 command needs to specify the
9784 command shall not, the following will help out the latter (with enabled
9788 level \*(UA will show information about handler evaluation):
9790 .Bd -literal -offset indent
9791 application/postscript; ps-to-terminal %s; needsterminal
9792 application/postscript; ps-to-terminal %s; compose=idraw %s
9796 In fields any occurrence of the format string
9798 will be replaced by the
9801 Named parameters from the
9803 field may be placed in the command execution line using
9805 followed by the parameter name and a closing
9808 The entire parameter should appear as a single command line argument,
9809 regardless of embedded spaces; thus:
9811 .Bd -literal -offset indent
9813 Content-type: multipart/mixed; boundary=42
9816 multipart/*; /usr/local/bin/showmulti \e
9817 %t %{boundary} ; composetyped = /usr/local/bin/makemulti
9819 # Executed shell command
9820 /usr/local/bin/showmulti multipart/mixed 42
9824 .\" TODO v15: Mailcap: %n,%F
9825 Note that \*(UA does not support handlers for multipart MIME parts as
9826 shown in this example (as of today).
9827 \*(UA does not support the additional formats
9831 An example file, also showing how to properly deal with the expansion of
9833 which includes any quotes that are necessary to make it a valid shell
9834 argument by itself and thus will cause undesired behaviour when placed
9835 in additional user-provided quotes:
9837 .Bd -literal -offset indent
9839 text/richtext; richtext %s; copiousoutput
9841 text/x-perl; perl -cWT %s
9845 trap "rm -f ${infile}" EXIT\e; \e
9846 trap "exit 75" INT QUIT TERM\e; \e
9848 x-mailx-async; x-mailx-tmpfile-keep
9850 application/*; echo "This is \e"%t\e" but \e
9851 is 50 \e% Greek to me" \e; < %s head -c 1024 | cat -vET; \e
9852 copiousoutput; x-mailx-noquote
9857 .Sx "HTML mail and MIME attachments" ,
9858 .Sx "The mime.types files" ,
9861 .Va mime-counter-evidence ,
9862 .Va pipe-TYPE/SUBTYPE ,
9863 .Va pipe-EXTENSION .
9866 .\" .Ss "The .netrc file" {{{
9867 .Ss "The .netrc file"
9871 file contains user credentials for machine accounts.
9872 The default location in the user's
9874 directory may be overridden by the
9876 environment variable.
9877 The file consists of space, tabulator or newline separated tokens.
9878 \*(UA implements a parser that supports a superset of the original BSD
9879 syntax, but users should nonetheless be aware of portability glitches
9880 of that file format, shall their
9882 be usable across multiple programs and platforms:
9885 .Bl -bullet -compact
9887 BSD does not support single, but only double quotation marks, e.g.,
9888 .Ql password="pass with spaces" .
9890 BSD (only?) supports escaping of single characters via a reverse solidus
9891 (e.g., a space can be escaped via
9893 in- as well as outside of a quoted string.
9895 BSD does not require a final quotation mark of the last user input token.
9897 The original BSD (Berknet) parser also supported a format which allowed
9898 tokens to be separated with commas \(en whereas at least Hewlett-Packard
9899 still seems to support this syntax, \*(UA does not!
9901 As a non-portable extension some widely-used programs support
9902 shell-style comments: if an input line starts, after any amount of
9903 whitespace, with a number sign
9905 then the rest of the line is ignored.
9907 Whereas other programs may require that the
9909 file is accessible by only the user if it contains a
9915 \*(UA will always require these strict permissions.
9919 Of the following list of supported tokens \*(UA only uses (and caches)
9924 At runtime the command
9926 can be used to control \*(UA's
9930 .Bl -tag -width password
9931 .It Cd machine Ar name
9932 The hostname of the entries' machine, lowercase-normalized by \*(UA
9934 Any further file content, until either end-of-file or the occurrence
9939 first-class token is bound (only related) to the machine
9942 As an extension that should not be the cause of any worries
9943 \*(UA supports a single wildcard prefix for
9945 .Bd -literal -offset indent
9946 machine *.example.com login USER password PASS
9947 machine pop3.example.com login USER password PASS
9948 machine smtp.example.com login USER password PASS
9954 .Ql pop3.example.com ,
9958 .Ql local.smtp.example.com .
9959 Note that in the example neither
9960 .Ql pop3.example.com
9962 .Ql smtp.example.com
9963 will be matched by the wildcard, since the exact matches take
9964 precedence (it is however faster to specify it the other way around).
9969 except that it is a fallback entry that is used shall none of the
9970 specified machines match; only one default token may be specified,
9971 and it must be the last first-class token.
9973 .It Cd login Ar name
9974 The user name on the remote machine.
9976 .It Cd password Ar string
9977 The user's password on the remote machine.
9979 .It Cd account Ar string
9980 Supply an additional account password.
9981 This is merely for FTP purposes.
9983 .It Cd macdef Ar name
9985 A macro is defined with the specified
9987 it is formed from all lines beginning with the next line and continuing
9988 until a blank line is (consecutive newline characters are) encountered.
9991 entries cannot be utilized by multiple machines, too, but must be
9992 defined following the
9994 they are intended to be used with.)
9997 exists, it is automatically run as the last step of the login process.
9998 This is merely for FTP purposes.
10005 .\" .Sh EXAMPLES {{{
10008 .\" .Ss "An example configuration" {{{
10009 .Ss "An example configuration"
10011 .Bd -literal -offset indent
10012 # This example assumes v15.0 compatibility mode
10015 # Where are the up-to-date SSL certificates?
10016 #set ssl-ca-dir=/etc/ssl/certs
10017 set ssl-ca-file=/etc/ssl/certs/ca-certificates.crt
10019 # (Since we manage up-to-date ones explicitly, do not use any,
10020 # possibly outdated, default certificates shipped with OpenSSL)
10021 set ssl-no-default-ca
10023 # Do not use protocols older than TLS v1.2.
10024 # Change this only when the remote server does not support it:
10025 # maybe use ssl-protocol-HOST (or -USER@HOST) syntax to define
10026 # such explicit exceptions, then
10027 set ssl-protocol='-ALL,+TLSv1.2'
10029 # Explicitly define the list of ciphers, which may improve security,
10030 # especially with protocols older than TLS v1.2. See ciphers(1).
10031 # Including "@STRENGTH" will sort the final list by algorithm strength.
10032 # In reality it is possibly best to only use ssl-cipher-list-HOST
10033 # (or -USER@HOST), as necessary, again..
10034 set ssl-cipher-list=TLSv1.2:!aNULL:!eNULL:!MEDIUM:!LOW:!EXPORT:@STRENGTH
10035 # ALL:!aNULL:!MEDIUM:!LOW:!MD5:!RC4:!EXPORT:@STRENGTH
10037 # Request strict transport security checks!
10038 set ssl-verify=strict
10040 # Essential setting: select allowed character sets
10041 set sendcharsets=utf-8,iso-8859-1
10043 # A very kind option: when replying to a message, first try to
10044 # use the same encoding that the original poster used herself!
10045 set reply-in-same-charset
10047 # When replying to or forwarding a message the comment and name
10048 # parts of email addresses are removed unless this variable is set
10051 # When sending messages, wait until the Mail-Transfer-Agent finishs.
10052 # Only like this you will be able to see errors reported through the
10053 # exit status of the MTA (including the builtin SMTP one)!
10056 # Only use builtin MIME types, no mime.types(5) files
10057 set mimetypes-load-control
10059 # Default directory where we act in (relative to $HOME)
10061 # A leading "+" (often) means: under *folder*
10062 # *record* is used to save copies of sent messages
10063 set MBOX=+mbox.mbox record=+sent.mbox DEAD=+dead.txt
10065 # Make "file mymbox" and "file myrec" go to..
10066 shortcut mymbox %:+mbox.mbox myrec +sent.mbox
10068 # Not really optional, e.g., for S/MIME
10069 set from='Your Name <address@exam.ple>'
10071 # It may be necessary to set hostname and/or smtp-hostname
10072 # if the "SERVER" of mta and "domain" of from do not match.
10073 # The `urlencode' command can be used to encode USER and PASS
10074 set mta=(smtps?|submission)://[USER[:PASS]@]SERVER[:PORT] \e
10075 smtp-auth=login/plain... \e
10078 # Never refuse to start into interactive mode, and more
10080 colour-pager crt= \e
10081 followup-to followup-to-honour=ask-yes \e
10082 history-file=+.\*(uAhist history-size=-1 history-gabby \e
10083 mime-counter-evidence=0xE \e
10084 prompt='[\e${-account-name} \e${-mailbox-display}]? ' \e
10085 reply-to-honour=ask-yes \e
10088 # Only include the selected header fields when typing messages
10089 headerpick type retain add from_ date from to cc subject \e
10090 message-id mail-followup-to reply-to
10091 # ...when forwarding messages
10092 headerpick forward retain add subject date from to cc
10093 # ...when saving message, etc.
10094 #headerpick save ignore add ^Original-.*$ ^X-.*$
10096 # Some mailing lists
10097 mlist '@xyz-editor\e.xyz$' '@xyzf\e.xyz$'
10098 mlsubscribe '^xfans@xfans\e.xyz$'
10100 # A real life example of a very huge free mail provider
10102 set folder=~/spool/XooglX inbox=+syste.mbox sent=+sent
10103 set from='Your Name <address@examp.ple>'
10104 set mta=smtp://USER:PASS@smtp.gmXil.com smtp-use-starttls
10107 # Here is a pretty large one which does not allow sending mails
10108 # if there is a domain name mismatch on the SMTP protocol level,
10109 # which would bite us if the value of from does not match, e.g.,
10110 # for people who have a sXXXXeforge project and want to speak
10111 # with the mailing list under their project account (in from),
10112 # still sending the message through their normal mail provider
10114 set folder=~/spool/XandeX inbox=+syste.mbox sent=+sent
10115 set from='Your Name <address@exam.ple>'
10116 set mta=smtps://USER:PASS@smtp.yaXXex.ru:465 \e
10117 hostname=yaXXex.com smtp-hostname=
10120 # Create some new commands so that, e.g., `ls /tmp' will..
10121 wysh ghost lls '!ls ${LS_COLOR_FLAG} -aFlrS'
10122 wysh ghost llS '!ls ${LS_COLOR_FLAG} -aFlS'
10123 wysh ghost ls '!ls ${LS_COLOR_FLAG} -aFrS'
10124 wysh ghost lS '!ls ${LS_COLOR_FLAG} -aFS'
10125 wysh ghost lla '!ls ${LS_COLOR_FLAG} -aFlr'
10126 wysh ghost llA '!ls ${LS_COLOR_FLAG} -aFl'
10127 wysh ghost la '!ls ${LS_COLOR_FLAG} -aFr'
10128 wysh ghost lA '!ls ${LS_COLOR_FLAG} -aF'
10129 wysh ghost ll '!ls ${LS_COLOR_FLAG} -aFltr'
10130 wysh ghost lL '!ls ${LS_COLOR_FLAG} -aFlt'
10131 wysh ghost l '!ls ${LS_COLOR_FLAG} -aFtr'
10132 wysh ghost L '!ls ${LS_COLOR_FLAG} -aFt'
10134 # We do not support gpg(1) directly yet. But simple --clearsign'd
10135 # message parts can be dealt with as follows:
10137 wysh set pipe-text/plain=$'@*#++=@\e
10138 < "${NAIL_FILENAME_TEMPORARY}" awk \e
10139 -v TMPFILE="${NAIL_FILENAME_TEMPORARY}" \e'\e
10141 /^-----BEGIN PGP SIGNED MESSAGE-----/,/^$/{\e
10144 print "--- GPG --verify ---";\e
10145 system("gpg --verify " TMPFILE " 2>&1");\e
10146 print "--- GPG --verify ---";\e
10150 /^-----BEGIN PGP SIGNATURE-----/,\e
10151 /^-----END PGP SIGNATURE-----/{\e
10161 !printf 'Key IDs to gpg --recv-keys: ';\e
10163 gpg --recv-keys ${keyids};
10169 When storing passwords in
10171 appropriate permissions should be set on this file with
10172 .Ql $ chmod 0600 \*(ur .
10175 is available user credentials can be stored in the central
10177 file instead; e.g., here is a different version of the example account
10178 that sets up SMTP and POP3:
10180 .Bd -literal -offset indent
10182 set folder=~/spool/XandeX inbox=+syste.mbox sent=+sent
10183 set from='Your Name <address@exam.ple>'
10185 # Load an encrypted ~/.netrc by uncommenting the next line
10186 #set netrc-pipe='gpg -qd ~/.netrc.pgp'
10188 set mta=smtps://smtp.yXXXXx.ru:465 \e
10189 smtp-hostname= hostname=yXXXXx.com
10190 set pop3-keepalive=240 pop3-no-apop-pop.yXXXXx.ru
10191 ghost xp fi pop3s://pop.yXXXXx.ru
10200 .Bd -literal -offset indent
10201 machine *.yXXXXx.ru login USER password PASS
10205 This configuration should now work just fine:
10208 .Dl $ echo text | \*(uA -vv -AXandeX -s Subject user@exam.ple
10211 .\" .Ss "Signed and encrypted messages with S/MIME" {{{
10212 .Ss "Signed and encrypted messages with S/MIME"
10214 \*(OP S/MIME provides two central mechanisms:
10215 message signing and message encryption.
10216 A signed message contains some data in addition to the regular text.
10217 The data can be used to verify that the message was sent using a valid
10218 certificate, that the sender's address in the message header matches
10219 that in the certificate, and that the message text has not been altered.
10220 Signing a message does not change its regular text;
10221 it can be read regardless of whether the recipient's software is able to
10225 It is thus usually possible to sign all outgoing messages if so desired.
10226 Encryption, in contrast, makes the message text invisible for all people
10227 except those who have access to the secret decryption key.
10228 To encrypt a message, the specific recipient's public encryption key
10230 It is therefore not possible to send encrypted mail to people unless their
10231 key has been retrieved from either previous communication or public key
10233 A message should always be signed before it is encrypted.
10234 Otherwise, it is still possible that the encrypted message text is
10238 A central concept to S/MIME is that of the certification authority (CA).
10239 A CA is a trusted institution that issues certificates.
10240 For each of these certificates it can be verified that it really
10241 originates from the CA, provided that the CA's own certificate is
10243 A set of CA certificates is usually delivered with OpenSSL and installed
10245 If you trust the source of your OpenSSL software installation,
10246 this offers reasonable security for S/MIME on the Internet.
10248 .Va smime-no-default-ca
10249 to avoid using the default certificate and point
10253 to a trusted pool of certificates.
10254 In general, a certificate cannot be more secure than the method its CA
10255 certificate has been retrieved with.
10258 The first thing you need for participating in S/MIME message exchange is
10259 your personal certificate, including a private key.
10260 The certificate contains public information, in particular your name and
10261 your email address(es), and the public key that is used by others to
10262 encrypt messages for you,
10263 and to verify signed messages they supposedly received from you.
10264 The certificate is included in each signed message you send.
10265 The private key must be kept secret.
10266 It is used to decrypt messages that were previously encrypted with your
10267 public key, and to sign messages.
10270 For personal use it is recommended that you get a S/MIME certificate
10271 from one of the major CAs on the Internet using your WWW browser.
10272 Many CAs offer such certificates for free.
10274 .Lk https://www.CAcert.org
10275 which issues client and server certificates to members of their
10276 community for free; their root certificate
10277 .Pf ( Lk https://\:www.cacert.org/\:certs/\:root.crt )
10278 is often not in the default set of trusted CA root certificates, though,
10279 which means you will have to download their root certificate separately
10280 and ensure it is part of our S/MIME certificate validation chain by
10283 or as a vivid member of the
10284 .Va smime-ca-file .
10285 But let us take a step-by-step tour on how to setup S/MIME with
10286 a certificate from CAcert.org despite this situation!
10289 First of all you will have to become a member of the CAcert.org
10290 community, simply by registrating yourself via the web interface.
10291 Once you are, create and verify all email addresses you want to be able
10292 to create signed and encrypted messages for/with using the corresponding
10293 entries of the web interface.
10294 Now ready to create S/MIME certificates, so let us create a new
10295 .Dq client certificate ,
10296 ensure to include all email addresses that should be covered by the
10297 certificate in the following web form, and also to use your name as the
10301 Create a private key and a certificate request on your local computer
10302 (please see the manual pages of the used commands for more in-depth
10303 knowledge on what the used arguments etc. do):
10306 .Dl openssl req -nodes -newkey rsa:4096 -keyout key.pem -out creq.pem
10309 Afterwards copy-and-paste the content of
10311 into the certificate-request (CSR) field of the web form on the
10312 CAcert.org website (you may need to unfold some
10313 .Dq advanced options
10314 to see the corresponding text field).
10315 This last step will ensure that your private key (which never left your
10316 box) and the certificate belong together (through the public key that
10317 will find its way into the certificate via the certificate-request).
10318 You are now ready and can create your CAcert certified certificate.
10319 Download and store or copy-and-paste it as
10324 In order to use your new S/MIME setup you will have to create
10325 a combined private key/public key (certificate) file:
10328 .Dl cat key.pem pub.crt > ME@HERE.com.paired
10331 This is the file \*(UA will work with.
10332 If you have created your private key with a passphrase then \*(UA will
10333 ask you for it whenever a message is signed or decrypted.
10334 Set the following variables to henceforth use S/MIME (setting
10336 is of interest for verification only):
10338 .Bd -literal -offset indent
10339 set smime-ca-file=ALL-TRUSTED-ROOT-CERTS-HERE \e
10340 smime-sign-cert=ME@HERE.com.paired \e
10341 smime-sign-message-digest=SHA256 \e
10346 From each signed message you send, the recipient can fetch your
10347 certificate and use it to send encrypted mail back to you.
10348 Accordingly if somebody sends you a signed message, you can do the same,
10351 command to check the validity of the certificate.
10354 Variables of interest for S/MIME signing:
10356 .Va smime-ca-file ,
10357 .Va smime-crl-dir ,
10358 .Va smime-crl-file ,
10359 .Va smime-no-default-ca ,
10361 .Va smime-sign-cert ,
10362 .Va smime-sign-include-certs
10364 .Va smime-sign-message-digest .
10367 After it has been verified save the certificate via
10369 and tell \*(UA that it should use it for encryption for further
10370 communication with that somebody:
10372 .Bd -literal -offset indent
10374 set smime-encrypt-USER@HOST=FILENAME \e
10375 smime-cipher-USER@HOST=AES256
10379 Additional variables of interest for S/MIME en- and decryption:
10382 .Va smime-encrypt-USER@HOST .
10385 You should carefully consider if you prefer to store encrypted messages
10387 If you do, anybody who has access to your mail folders can read them,
10388 but if you do not, you might be unable to read them yourself later if
10389 you happen to lose your private key.
10392 command saves messages in decrypted form, while the
10396 commands leave them encrypted.
10399 Note that neither S/MIME signing nor encryption applies to message
10400 subjects or other header fields yet.
10401 Thus they may not contain sensitive information for encrypted messages,
10402 and cannot be trusted even if the message content has been verified.
10403 When sending signed messages,
10404 it is recommended to repeat any important header information in the
10408 .\" .Ss "Using CRLs with S/MIME or SSL/TLS" {{{
10409 .Ss "Using CRLs with S/MIME or SSL/TLS"
10411 \*(OP Certification authorities (CAs) issue certificate revocation
10412 lists (CRLs) on a regular basis.
10413 These lists contain the serial numbers of certificates that have been
10414 declared invalid after they have been issued.
10415 Such usually happens because the private key for the certificate has
10417 because the owner of the certificate has left the organization that is
10418 mentioned in the certificate, etc.
10419 To seriously use S/MIME or SSL/TLS verification,
10420 an up-to-date CRL is required for each trusted CA.
10421 There is otherwise no method to distinguish between valid and
10422 invalidated certificates.
10423 \*(UA currently offers no mechanism to fetch CRLs, nor to access them on
10424 the Internet, so you have to retrieve them by some external mechanism.
10427 \*(UA accepts CRLs in PEM format only;
10428 CRLs in DER format must be converted, like, e.\|g.:
10431 .Dl $ openssl crl \-inform DER \-in crl.der \-out crl.pem
10434 To tell \*(UA about the CRLs, a directory that contains all CRL files
10435 (and no other files) must be created.
10440 variables, respectively, must then be set to point to that directory.
10441 After that, \*(UA requires a CRL to be present for each CA that is used
10442 to verify a certificate.
10445 .\" .Ss "Handling spam" {{{
10446 .Ss "Handling spam"
10448 \*(OP \*(UA can make use of several spam interfaces for the purpose of
10449 identification of, and, in general, dealing with spam messages.
10450 A precondition of most commands in order to function is that the
10452 variable is set to one of the supported interfaces.
10453 Once messages have been identified as spam their (volatile)
10455 state can be prompted: the
10459 message specifications will address respective messages and their
10461 entries will be used when displaying the
10463 in the header display.
10468 rates the given messages and sets their
10471 If the spam interface offers spam scores those can also be displayed in
10472 the header display by including the
10482 will interact with the Bayesian filter of the chosen interface and learn
10483 the given messages as
10487 respectively; the last command can be used to cause
10489 of messages; it adheres to their current
10491 state and thus reverts previous teachings.
10496 will simply set and clear, respectively, the mentioned volatile
10498 message flag, without any interface interaction.
10507 requires a running instance of the
10509 server in order to function, started with the option
10511 shall Bayesian filter learning be possible.
10513 .Bd -literal -offset indent
10514 $ spamd -i localhost:2142 -i /tmp/.spamsock -d [-L] [-l]
10515 $ spamd --listen=localhost:2142 --listen=/tmp/.spamsock \e
10516 --daemonize [--local] [--allow-tell]
10520 Thereafter \*(UA can make use of these interfaces:
10522 .Bd -literal -offset indent
10523 $ \*(uA -Sspam-interface=spamc -Sspam-maxsize=500000 \e
10524 -Sspamc-command=/usr/local/bin/spamc \e
10525 -Sspamc-arguments="-U /tmp/.spamsock" -Sspamc-user=
10527 $ \*(uA -Sspam-interface=spamc -Sspam-maxsize=500000 \e
10528 -Sspamc-command=/usr/local/bin/spamc \e
10529 -Sspamc-arguments="-d localhost -p 2142" -Sspamc-user=
10533 Using the generic filter approach allows usage of programs like
10535 Here is an example, requiring it to be accessible via
10538 .Bd -literal -offset indent
10539 $ \*(uA -Sspam-interface=filter -Sspam-maxsize=500000 \e
10540 -Sspamfilter-ham="bogofilter -n" \e
10541 -Sspamfilter-noham="bogofilter -N" \e
10542 -Sspamfilter-nospam="bogofilter -S" \e
10543 -Sspamfilter-rate="bogofilter -TTu 2>/dev/null" \e
10544 -Sspamfilter-spam="bogofilter -s" \e
10545 -Sspamfilter-rate-scanscore="1;^(.+)$"
10549 Because messages must exist on local storage in order to be scored (or
10550 used for Bayesian filter training), it is possibly a good idea to
10551 perform the local spam check last:
10553 .Bd -literal -offset indent
10554 define spamdelhook {
10556 spamset (header x-dcc-brand-metrics "bulk")
10557 # Server-side spamassassin(1)
10558 spamset (header x-spam-flag "YES")
10559 del :s # TODO we HAVE to be able to do `spamrate :u ! :sS'
10560 move :S +maybe-spam
10563 move :S +maybe-spam
10565 set folder-hook-FOLDER=spamdelhook
10569 See also the documentation for the variables
10570 .Va spam-interface , spam-maxsize ,
10571 .Va spamc-command , spamc-arguments , spamc-user ,
10572 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
10575 .Va spamfilter-rate-scanscore .
10583 In general it is a good idea to turn on
10589 twice) if something does not work well.
10590 Very often a diagnostic message can be produced that leads to the
10591 problems' solution.
10593 .\" .Ss "\*(UA shortly hangs on startup" {{{
10594 .Ss "\*(UA shortly hangs on startup"
10596 This can have two reasons, one is the necessity to wait for a file lock
10597 and cannot be helped, the other being that \*(UA calls the function
10599 in order to query the nodename of the box (sometimes the real one is
10600 needed instead of the one represented by the internal variable
10602 You may have varying success by ensuring that the real hostname and
10606 or, more generally, that the name service is properly setup \(en
10609 return what you would expect?
10610 Does this local hostname has a domain suffix?
10611 RFC 6762 standardized the link-local top-level domain
10615 .\" .Ss "\*(UA exits quick, and output is cleared away" {{{
10616 .Ss "\*(UA exits quick, and output is cleared away"
10618 When this happens even with
10620 set, then this most likely indicates a problem with the creation of
10621 so-called dotlock files: setting
10622 .Va dotlock-ignore-error
10623 should overcome this situation.
10624 This only avoids symptoms, it does not address the problem, though.
10625 Since the output is cleared away \*(UA has support for
10626 .Sx "On terminal control and line editor" ,
10627 and switches to the
10629 which causes the output clearance: by doing
10630 .Ql set termcap='smcup='
10631 this mode can be suppressed, and by setting
10633 (twice) the actual problem should be reported.
10636 .\" .Ss "I cannot login to Google mail aka GMail" {{{
10637 .Ss "I cannot login to Google mail aka GMail"
10639 Since 2014 some free service providers classify programs as
10641 unless they use a special authentification method (OAuth 2.0) which
10642 was not standardized for non-HTTP protocol authentication token query
10643 until August 2015 (RFC 7628).
10646 Different to Kerberos / GSSAPI, which is developed since the mid of the
10647 1980s, where a user can easily create a local authentication ticket for
10648 her- and himself with the locally installed
10650 program, that protocol has no such local part but instead requires
10651 a world-wide-web query to create or fetch a token; since there is no
10652 local cache this query has to be performed whenever \*(UA is invoked
10653 from the command line (in interactive sessions situation may differ).
10656 \*(UA does not support OAuth.
10657 Because of this it is necessary to declare \*(UA a
10658 .Dq less secure app
10659 (on the providers account web page) in order to read and send mail.
10660 However, it also seems possible to take the following steps instead:
10665 give the provider the number of a mobile phone,
10668 .Dq 2-Step Verification ,
10670 create an application specific password (16 characters), and
10672 use that special password instead of your real Google account password in
10673 \*(UA (for more on that see the section
10674 .Sx "On URL syntax and credential lookup" ) .
10678 .\" .Ss "Not \(dqdefunctional\(dq, but the editor key does not work" {{{
10679 .Ss "Not \(dqdefunctional\(dq, but the editor key does not work"
10681 It can happen that the terminal library (see
10682 .Sx "On terminal control and line editor",
10685 reports different codes than the terminal really sends, in which case
10686 \*(UA will tell that a key binding is functional, but will not be able to
10687 recognize it because the received data does not match anything expected.
10688 The verbose listing of
10690 ings will show the byte sequences that are expected.
10693 To overcome the situation, use, e.g., the program
10695 in conjunction with the
10697 flag if available, to see the byte sequences which are actually produced
10698 by keypresses, and use the variable
10700 to make \*(UA aware of them.
10701 E.g., the terminal this is typed on produces some false sequences, here
10702 an example showing the shifted home key:
10704 .Bd -literal -offset indent
10707 # 1B 5B=[ 31=1 3B=; 32=2 48=H
10712 ? \*(uA -v -Stermcap='kHOM=\eE[H'
10721 .\" .Sh "SEE ALSO" {{{
10731 .Xr spamassassin 1 ,
10740 .Xr mailwrapper 8 ,
10745 .\" .Sh HISTORY {{{
10748 M. Douglas McIlroy writes in his article
10749 .Dq A Research UNIX Reader: Annotated Excerpts \
10750 from the Programmer's Manual, 1971-1986
10753 command already appeared in First Edition
10757 .Bd -ragged -offset indent
10758 Electronic mail was there from the start.
10759 Never satisfied with its exact behavior, everybody touched it at one
10760 time or another: to assure the safety of simultaneous access, to improve
10761 privacy, to survive crashes, to exploit uucp, to screen out foreign
10762 freeloaders, or whatever.
10763 Not until v7 did the interface change (Thompson).
10764 Later, as mail became global in its reach, Dave Presotto took charge and
10765 brought order to communications with a grab-bag of external networks
10771 Mail was written in 1978 by Kurt Shoens and developed as part of the
10774 distribution until 1995.
10775 Mail has then seen further development in open source
10777 variants, noticeably by Christos Zoulas in
10779 Basing upon this Nail, later Heirloom Mailx, was developed by Gunnar
10780 Ritter in the years 2000 until 2008.
10781 Since 2012 S-nail is maintained by Steffen (Daode) Nurpmeso.
10782 This man page is derived from
10783 .Dq The Mail Reference Manual
10784 that was originally written by Kurt Shoens.
10790 .An "Kurt Shoens" ,
10791 .An "Edward Wang" ,
10792 .An "Keith Bostic" ,
10793 .An "Christos Zoulas" ,
10794 .An "Gunnar Ritter" ,
10795 .An "Steffen Nurpmeso" Aq Mt s-nail-users@lists.sourceforge.net
10797 .Mt s-mailx@sdaoden.eu ) .
10800 .\" .Sh CAVEATS {{{
10803 \*(ID Interrupting an operation via
10807 is often problematic: many library functions cannot deal with the
10809 that this software (still) performs.
10812 The SMTP and POP3 protocol support of \*(UA is very basic.
10813 Also, if it fails to contact its upstream SMTP server, it will not make
10814 further attempts to transfer the message at a later time (setting
10819 If this is a concern, it might be better to set up a local SMTP server
10820 that is capable of message queuing.
10826 After deleting some message of a POP3 mailbox the header summary falsely
10827 claims that there are no messages to display, you need to perform
10828 a scroll or dot movement to restore proper state.
10830 In threaded display a power user may encounter crashes very
10831 occasionally (this is may and very).
10835 in the source repository lists future directions.