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-pre1 / 2016-09-15
36 .ds VV \\%v14.9.0-pre1
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.
152 It is usable as a mail batch language.
154 .\" .Ss "Options" {{{
157 .Bl -tag -width ".Fl _ Ar _ddr"
160 Explicitly control which of the
162 shall be loaded: if the letter
164 is (case-insensitively) part of the
168 is loaded, likewise the letter
170 controls loading of the user's personal
172 file, whereas the letters
176 explicitly forbid loading of any resource files.
177 This option should be used by scripts: to avoid environmental noise they
180 from any configuration files and create a script-local environment,
181 explicitly setting any of the desired
182 .Sx "INTERNAL VARIABLES"
185 This option overrides
192 command for the given user email
194 after program startup is complete.
195 Being a special incarnation of
197 macros for the purpose of bundling longer-lived settings, activating
198 such an email account also switches to the accounts
204 Attach the given file to the message.
205 The same filename conventions as described in the section
207 apply: shell word expansion is restricted to the tilde
211 not be accessible but contain a
213 character, then anything after the
215 is assumed to specify the input character set and anything before
217 the filename: this is the only option to specify the input character set
218 (and don't perform any character set conversion) for text attachments
219 from the command line, not using the
221 tilde escape command.
225 Make standard input and standard output line-buffered.
229 Send a blind carbon copy to
232 May be used multiple times.
234 .Sx "On sending mail, and non-interactive mode" .
238 Send carbon copies to the given receiver.
239 May be used multiple times.
244 the internal variable
246 which enables debug messages and disables message delivery,
247 among others; effectively turns almost any operation into a dry-run.
253 and thus discard messages with an empty message part body.
254 This is useful for sending messages from scripts.
258 Just check if mail is present (in the specified or system
260 box): if yes, return an exit status of zero, a non-zero value otherwise.
261 To restrict the set of mails to consider in this evaluation a message
262 specification can be added with the option
267 Save the message to send in a file named after the local part of the
268 first recipient's address (instead of in
273 Read in the contents of the user's
275 (or the specified file) for processing;
276 when \*(UA is quit, it writes undeleted messages back to this file
280 Some special conventions are recognized for the optional
282 argument which are documented for the
287 is not a argument to the flag
289 but is instead taken from the command line after option processing has
293 that starts with a hyphen, prefix it with a (relative) path, as in
294 .Ql ./-hyphenbox.mbox .
298 Display a summary of the
300 of all messages in the specified or system
303 A configurable summary view is available via the
309 Show a short usage summary.
310 Because of widespread use a
312 argument will have the same effect.
318 to ignore tty interrupt signals.
321 .It Fl L Ar spec-list
322 Display a summary of all
324 of only those messages in the specified or system
326 box that match the given
330 .Sx "Specifying messages"
337 option has been given in addition no header summary is produced,
338 but \*(UA will instead indicate via its exit status whether
344 note that any verbose output is suppressed in this mode and must instead
345 be enabled explicitly (e.g., by using the option
350 Special send mode that will flag standard input with the MIME
354 and use it as the main message body.
355 \*(ID Using this option will bypass processing of
356 .Va message-inject-head ,
359 .Va message-inject-tail .
365 Special send mode that will MIME classify the specified
367 and use it as the main message body.
368 \*(ID Using this option will bypass processing of
369 .Va message-inject-head ,
372 .Va message-inject-tail .
380 and thus inhibit initial display of message headers when reading mail or
381 editing a mail folder.
385 Standard flag that inhibits reading the system wide
390 allows more control over the startup sequence; also see
391 .Sx "Resource files" .
395 Special send mode that will initialize the message body with the
396 contents of the specified
398 which may be standard input
400 only in non-interactive context.
406 Any folder opened will be in read-only mode.
409 .It Fl r Ar from-addr
412 is a valid address then it specifies the envelope sender address to be
413 passed to a file-based
415 (Mail-Transfer-Agent) as
417 when a message is send.
420 include a user name, then the address components will be separated and
421 the name part will be passed to file-based
427 will also be assigned to the
430 .Ql -Sfrom=from-addr ) ,
431 therefore affecting possible SMTP
433 data transfer; note this assignment does not cause value fixation.
435 If instead an empty string is passed as
437 then the content of the variable
439 will be evaluated and used for this purpose whenever the
442 Note that \*(UA by default, without
444 that is, neither passes
448 flags to a file-based MTA by itself.
451 .It Fl S Ar var Ns Op = Ns value
455 iable and, in case of a non-boolean variable which has a value, assign
459 .Sx "INTERNAL VARIABLES"
463 may be overwritten from within resource files,
464 the command line setting will be reestablished after all resource files
469 Specify the subject of the to-be-sent message.
473 The message given (on standard input) is expected to contain, separated
474 from the message body by an empty line, a message header with
479 fields giving its recipients, which will be added to any recipients
480 specified on the command line.
481 If a message subject is specified via
483 then it'll be used in favour of one given on the command line.
499 .Ql Mail-Followup-To: ,
500 by default created automatically dependent on message context, will
501 be used if specified (a special address massage will however still occur
503 Any other (even custom) header field is passed through entirely
504 unchanged, and in conjunction with the option
506 it is even possible to embed
513 Initially read the primary system mailbox of
515 appropriate privileges presumed; effectively identical to
527 ting the internal variable
529 enables display of some informational context messages.
530 Using it twice increases the level of verbosity.
536 to the list of commands to be executed before normal operation starts.
540 .Va batch-exit-on-error ;
541 the only possibility to execute commands in non-interactive mode when
542 reading startup files is actively prohibited.
548 even if not in interactive mode.
549 This can be used to, e.g., automatically format the composed message
550 text before sending the message:
551 .Bd -literal -offset indent
552 $ ( echo 'line one. Word. Word2.'; \e
553 echo '~| /usr/bin/fmt -tuw66' ) |\e
554 LC_ALL=C \*(uA -:/ -Sttycharset=UTF-8 -d~ bob@exam.ple
560 In batch mode the full set of commands is available, just like in
561 interactive mode, and diverse variable settings and internal states are
562 adjusted for batch necessities, e.g., it
578 is enabled in compose mode.
579 The following prepares an email message in a batched dry run:
580 .Bd -literal -offset indent
581 $ LC_ALL=C printf 'm bob\en~s ubject\enText\en~.\enx\en' | \e
582 LC_ALL=C \*(uA -:/ -d# -X'alias bob bob@exam.ple'
587 This flag forces termination of option processing in order to prevent
590 It also forcefully puts \*(UA into send mode, see
591 .Sx "On sending mail, and non-interactive mode" .
595 In the above list of supported command line options,
599 are implemented by means of
601 ting the respective option, as via
604 .Op Ar mta-option ...
606 arguments that are given at the end of the command line after a
608 separator will be passed through to a file-based
610 (Mail-Transfer-Agent) and persist for an entire (interactive) session
611 \(en if the setting of
613 allows their recognition; no such constraints apply to the variable
617 .\" .Ss "A starter" {{{
620 \*(UA is a direct descendant of
622 Mail, a successor of the Research
625 .Dq was there from the start
630 Mail reference manual begins with the following words:
632 .Bd -ragged -offset indent
633 Mail provides a simple and friendly environment for sending and
635 It divides incoming mail into its constituent messages and allows the
636 user to deal with them in any order.
637 In addition, it provides a set of
639 -like commands for manipulating messages and sending mail.
640 Mail offers the user simple editing capabilities to ease the composition
641 of outgoing messages, as well as providing the ability to define and
642 send to names which address groups of users.
646 \*(UA is thus the user side of the
648 mail system, whereas the system side (Mail-Transfer-Agent, MTA) was
649 traditionally taken by
651 and most MTAs provide a binary of this name for compatibility purposes.
656 of \*(UA then the system side is not a mandatory precondition for mail
660 Because \*(UA strives for compliance with POSIX
662 it is likely that some configuration settings have to be adjusted before
663 using it is a smooth experience.
666 file already bends those standard imposed settings a bit towards more
667 user friendliness and safety, e.g., it
669 s the internal variables
673 in order to suppress the automatic moving of messages to
675 that would otherwise occur (see
676 .Sx "Message states" )
679 to not remove empty files in order not to mangle file permissions when
680 files eventually get recreated (\*(UA actively manages the file mode
683 upon program startup).
687 .Sx "INTERNAL VARIABLES" ,
688 isn't set by default so that file grouping (via the
690 prefix as documented for
692 is not functional by default.
695 contains some suggestions.
698 .\" .Ss "On sending mail, and non-interactive mode" {{{
699 .Ss "On sending mail, and non-interactive mode"
701 To send a message to one or more people, using a local or a builtin
703 (Mail-Transfer-Agent) transport to actually deliver the generated mail
704 message, \*(UA can be invoked with arguments which are the names of
705 people to whom the mail will be sent, and the command line options
709 can be used to add (blind) carbon copy receivers:
711 .Bd -literal -offset indent
712 $ \*(uA -s ubject -a ttach.txt bill@exam.ple
713 # But... try it in an isolated dry-run mode first
714 $ LC_ALL=C \*(uA -:/ -d -vv -Ssendwait \e
715 -b bcc@exam.ple -c cc@exam.ple -. \e
716 '(Lovely) Bob <bob@exam.ple>' eric@exam.ple
718 $ LC_ALL=C \*(uA -:/ -d -vv -Sv15-compat -Ssendwait \e
719 -S 'mta=smtps://mylogin@exam.ple:465' -Ssmtp-auth=login \e
720 -S 'from=scriptreply@exam.ple' \e
726 If standard input is a terminal rather than the message to be sent,
727 the user is expected to type in the message contents.
728 In this compose mode \*(UA treats lines beginning with the character
730 special \(en these are so-called
732 which can be used to read in files, process shell commands, add and edit
733 attachments and more; e.g., the tilde escape
735 will start the text editor to revise the message in it's current state,
737 allows editing of the most important message headers and
739 gives an overview of available tilde escapes.
743 at the beginning of an empty line leaves compose mode and causes the
744 message to be sent, whereas typing
747 twice will abort the current letter (saving its contents in the file
753 Messages are sent asynchronously, without supervision, unless the variable
755 is set, therefore send errors are not recognizable until then.
761 .Sx "INTERNAL VARIABLES"
762 can be used to alter default behavior; e.g.,
767 will automatically startup a text editor when compose mode is entered,
769 will cause the user to be prompted actively for carbon-copy recipients
772 option will allow leaving compose mode by writing a line consisting
778 hook macros may be set to automatically adjust some settings dependent
779 on receiver, sender or subject contexts.
782 Especially for using public mail provider accounts with the SMTP
784 it is often necessary to set
786 and saving a copy of sent messages in a
788 may be desirable \(en as for most mailbox file targets some special
789 syntax conventions are recognized (see the
791 command for more on that).
794 for the purpose of arranging a complete environment of settings that can
795 be switched to with a single command or command line option may be
798 contains example configurations for sending messages via some of the
799 well-known public mail providers and also gives a compact overview on
800 how to setup a secure SSL/TLS environment).
805 sandbox dry-run tests first will prove correctness.
809 .Sx "On URL syntax and credential lookup"
810 will spread light on the different ways of how to specify user email
811 account credentials, the
813 variable chains, and accessing protocol-specific resources,
816 goes into the details of character encoding and how to use them for
817 representing messages and MIME part contents by specifying them in
819 and reading the section
820 .Sx "The mime.types files"
821 should help to understand how the MIME-type of outgoing attachments are
822 classified, and what can be done for fine-tuning.
825 Message recipients (as specified on the command line or defined in
830 may not only be email addressees but can also be names of mailboxes and
831 even complete shell command pipe specifications.
834 is not set then only network addresses (see
836 for a description of mail addresses) and plain user names (including MTA
837 aliases) may be used, other types will be filtered out, giving a warning
840 .\" When changing any of the following adjust any RECIPIENTADDRSPEC;
841 .\" grep the latter for the complete picture
845 is set then extended recipient addresses will optionally be accepted:
846 Any name which starts with a vertical bar
848 character specifies a command pipe \(en the command string following the
850 is executed and the message is sent to its standard input;
851 Likewise, any name that starts with the character solidus
853 or the character sequence dot solidus
855 is treated as a file, regardless of the remaining content.
856 Any other name which contains an at sign
858 character is treated as a network address;
859 Any other name which starts with a plus sign
861 character specifies a mailbox name;
862 Any other name which contains a solidus
864 character but no exclamation mark
868 character before also specifies a mailbox name;
869 What remains is treated as a network address.
871 .Bd -literal -offset indent
872 $ echo bla | \*(uA -Sexpandaddr -s test ./mbox.mbox
873 $ echo bla | \*(uA -Sexpandaddr -s test '|cat >> ./mbox.mbox'
874 $ echo safe | LC_ALL=C \e
875 \*(uA -:/ -Sv15-compat -Ssendwait -Snosave \e
876 -Sexpandaddr=fail,-all,+addr -s test \e
881 It is possible to create personal distribution lists via the
883 command, so that, for instance, the user can send mail to
885 and have it go to a group of people.
886 These aliases have nothing in common with the system wide aliases that
887 may be used by the MTA, which are subject to the
891 and are often tracked in a file
897 Personal aliases will be expanded by \*(UA before the message is sent,
898 and are thus a convenient alternative to specifying each addressee by
902 .Dl alias cohorts bill jkf mark kridle@ucbcory ~/mail/cohorts.mbox
905 To avoid environmental noise scripts should
907 \*(UA from any configuration files and create a script-local
908 environment, ideally with the command line options
910 to disable any configuration file in conjunction with repetitions of
912 to specify variables:
914 .Bd -literal -offset indent
915 $ env LC_ALL=C \*(uA -:/ \e
916 -Sv15-compat -Ssendwait -Snosave -Sttycharset=utf-8 \e
917 -Sexpandaddr=fail,-all,+addr \e
918 -S 'mta=smtps://mylogin@exam.ple:465' -Ssmtp-auth=login \e
919 -S 'from=scriptreply@exam.ple' \e
920 -s 'subject' -a attachment_file \e
921 -. "Recipient 1 <rec1@exam.ple>" rec2@exam.ple \e
926 As shown, scripts can
928 a locale environment, the above specifies the all-compatible 7-bit clean
931 but will nonetheless take and send UTF-8 in the message text by using
933 In interactive mode, which is introduced in the next section, messages
934 can be sent by calling the
936 command with a list of recipient addresses \(em the semantics are
937 completely identical to non-interactive message sending:
939 .Bd -literal -offset indent
940 $ \*(uA -d -Squiet -Semptystart
941 "/var/spool/mail/user": 0 messages
942 ? mail "Recipient 1 <rec1@exam.ple>", rec2@exam.ple
943 ? # Will do the right thing (tm)
944 ? m rec1@exam.ple rec2@exam.ple
948 .\" .Ss "On reading mail, and interactive mode" {{{
949 .Ss "On reading mail, and interactive mode"
951 When invoked without addressees \*(UA enters interactive mode in which
953 When used like that the user's system
957 for an in-depth description of the different mailbox types that exist)
958 is read in and a one line header of each message therein is displayed.
959 The visual style of this summary of
961 can be adjusted through the variable
963 and the possible sorting criterion via
965 If the initially opened mailbox is empty \*(UA will instead exit
966 immediately (after displaying a message) unless the variable
975 will give a listing of all available commands and
977 will give a summary of some common ones.
978 If the \*(OPal documentation strings are available one can type
980 and see the actual expansion of
982 and what it's purpose is, i.e., commands can be abbreviated
983 (note that POSIX defines some abbreviations, so that the alphabetical
984 order of commands doesn't necessarily relate to the abbreviations; it is
985 possible to define overwrites with the
990 Messages are given numbers (starting at 1) which uniquely identify
991 messages; the current message \(en the
993 \(en will either be the first new message, or the first unread message,
994 or the first message of the mailbox; the option
996 will instead cause usage of the last message for this purpose.
1001 ful of header summaries containing the
1005 will display only the summaries of the given messages, defaulting to the
1009 Message content can be displayed on the users' terminal with the
1013 If instead the command
1015 is used, only the first
1017 of a message will be shown.
1018 By default the current message
1020 is displayed, but like with many other commands it is possible to give
1021 a fancy message specification (see
1022 .Sx "Specifying messages" ) ,
1025 will display all unread messages,
1030 will type the messages 1 and 5,
1032 will type the messages 1 through 5, and
1036 will display the last and the next message, respectively.
1039 (a more substantial alias of the standard command
1041 will display a header summary of the given message specification list
1042 instead of their content, e.g., the following will search for subjects:
1045 .Dl from "'@Some subject to search for'"
1048 In the default setup all header fields of a message will be
1050 d, but this can be changed: either by blacklisting a list of fields via
1052 or by whitelisting only a given list with the
1055 .Ql Ic \:retain Ns \0from_ date from to cc subject .
1056 In order to display all header fields of a message regardless of
1057 currently active ignore or retain lists, use the commands
1063 controls whether and when \*(UA will use the configured
1065 for display instead of directly writing to the user terminal
1067 (generally speaking).
1068 Note that historically the global
1070 not only adjusts the list of displayed headers, but also sets
1074 Dependent upon the configuration a line editor (see the section
1075 .Sx "On terminal control and line editor" )
1076 aims at making user experience with the many
1079 When reading the system
1085 specified a mailbox explicitly prefixed with the special
1087 modifier (propagating the mailbox to a primary one) then messages which
1088 have been read will be moved to a secondary mailbox, the user's
1090 file, automatically when the mailbox is left, either by changing the
1091 active mailbox or by quitting \*(UA (also see
1092 .Sx "Message states" )
1093 \(en this automatic moving from a system or primary to the secondary
1094 mailbox is not performed when the variable
1099 After examining a message the user can also
1103 to the sender and all recipients or
1105 exclusively to the sender(s).
1106 Messages can also be
1108 ed (shorter alias is
1110 Note that when replying to or forwarding a message recipient addresses
1111 will be stripped from comments and names unless the option
1114 Deletion causes \*(UA to forget about the message;
1115 This is not irreversible, though, one can
1117 the message by giving its number,
1118 or the \*(UA session can be ended by giving the
1123 To end a mail processing session one may either issue
1125 to cause a full program exit, which possibly includes
1126 automatic moving of read messages to
1128 as well as updating the \*(OPal line editor
1132 instead in order to prevent any of these actions.
1135 .\" .Ss "HTML mail and MIME attachments" {{{
1136 .Ss "HTML mail and MIME attachments"
1138 Messages which are HTML-only get more and more common and of course many
1139 messages come bundled with a bouquet of MIME attachments.
1140 Whereas \*(UA \*(OPally supports a simple HTML-to-text converter to deal
1141 with HTML messages (see
1142 .Sx "The mime.types files" ) ,
1143 it normally can't deal with any of these itself, but instead programs
1144 need to become registered to deal with specific MIME types or file
1146 These programs may either prepare plain text versions of their input
1147 in order to enable \*(UA to display the content on the terminal,
1148 or display the content themselves, for example in a graphical window.
1151 To install an external handler program for a specific MIME type set an
1153 .Va pipe-TYPE/SUBTYPE
1154 variable; to instead define a handler for a specific file extension set
1157 variable \(en these handlers take precedence.
1158 \*(OPally \*(UA supports mail user agent configuration as defined in
1159 RFC 1524; this mechanism, documented in the section
1160 .Sx "The Mailcap files" ,
1161 will be queried for display or quote handlers if none of the former two
1162 .\" TODO v15-compat "will be" -> "is"
1163 did; it will be the sole source for handlers of other purpose.
1164 A last source for handlers may be the MIME type definition itself, if
1165 the \*(UA specific type-marker extension was used when defining the type
1168 (Many of the builtin MIME types do so by default.)
1172 .Va mime-counter-evidence
1173 can be set to improve dealing with faulty MIME part declarations as are
1174 often seen in real-life messages.
1175 E.g., to display a HTML message inline (that is, converted to a more
1176 fancy plain text representation than the builtin converter is capable to
1177 produce) with either of the text-mode browsers
1181 teach \*(UA about MathML documents and make it display them as plain
1182 text, and to open PDF attachments in an external PDF viewer,
1183 asynchronously and with some other magic attached:
1185 .Bd -literal -offset indent
1186 if $features !@ +filter-html-tagsoup
1187 #set pipe-text/html='elinks -force-html -dump 1'
1188 set pipe-text/html='lynx -stdin -dump -force_html'
1189 # Display HTML as plain text instead
1190 #set pipe-text/html=@
1192 mimetype '@ application/mathml+xml mathml'
1193 wysh set pipe-application/pdf='@&=@ \e
1194 trap "rm -f \e"${NAIL_FILENAME_TEMPORARY}\e"" EXIT;\e
1195 trap "trap \e"\e" INT QUIT TERM; exit 1" INT QUIT TERM;\e
1196 mupdf "${NAIL_FILENAME_TEMPORARY}"'
1200 Note: special care must be taken when using such commands as mail
1201 viruses may be distributed by this method: if messages of type
1202 .Ql application/x-sh
1203 or files with the extension
1205 were blindly filtered through the shell, for example, a message sender
1206 could easily execute arbitrary code on the system \*(UA is running on.
1207 For more on MIME, also in respect to sending of messages, see the
1209 .Sx "The mime.types files" ,
1210 .Sx "The Mailcap files"
1215 .\" .Ss "Mailing lists" {{{
1218 \*(UA offers some support to ease handling of mailing lists.
1221 promotes all given arguments to known mailing lists, and
1223 sets their subscription attribute, creating them first as necessary.
1228 automatically, but only resets the subscription attribute.)
1229 Using the commands without arguments will show (a subset of) all
1230 currently defined mailing lists.
1235 can be used to mark out messages with configured list addresses
1236 in the header display.
1239 \*(OPally mailing lists may also be specified as (extended) regular
1240 expressions, which allows matching of many addresses with a single
1242 However, all fully qualified list addresses are matched via a fast
1243 dictionary, whereas expressions are placed in (a) list(s) which is
1244 (are) matched sequentially.
1246 .Bd -literal -offset indent
1247 set followup-to followup-to-honour=ask-yes reply-to-honour=ask-yes
1248 wysh mlist a1@b1.c1 a2@b2.c2 '.*@lists\e.c3$'
1249 mlsubscribe a4@b4.c4 exact@lists.c3
1254 .Va followup-to-honour
1256 .Ql Mail-\:Followup-\:To:
1257 header is honoured when the message is being replied to (via
1263 controls whether this header is created when sending mails; it will be
1264 created automatically for a couple of reasons, too, like when the
1266 .Dq mailing list specific
1271 is used to respond to a message with its
1272 .Ql Mail-Followup-To:
1276 A difference in between the handling of known and subscribed lists is
1277 that the address of the sender is usually not part of a generated
1278 .Ql Mail-Followup-To:
1279 when addressing the latter, whereas it is for the former kind of lists.
1280 Usually because there are exceptions: say, if multiple lists are
1281 addressed and not all of them are subscribed lists.
1283 For convenience \*(UA will, temporarily, automatically add a list
1284 address that is presented in the
1286 header of a message that is being responded to to the list of known
1288 Shall that header have existed \*(UA will instead, dependent on the
1290 .Va reply-to-honour ,
1293 for this purpose in order to accept a list administrators' wish that
1294 is supposed to have been manifested like that (but only if it provides
1295 a single address which resides on the same domain as what is stated in
1299 .\" .Ss "Resource files" {{{
1300 .Ss "Resource files"
1302 Upon startup \*(UA reads in several resource files:
1304 .Bl -tag -width ".It Pa _AIL_EXTRA_R_"
1307 System wide initialization file.
1308 Reading of this file can be suppressed, either by using the
1312 command line options, or by setting the
1315 .Ev NAIL_NO_SYSTEM_RC .
1319 File giving initial commands.
1320 A different file can be chosen by setting the
1324 Reading of this file can be suppressed with the
1326 command line option.
1328 .It Va NAIL_EXTRA_RC
1329 Can be used to define an optional startup file to be read after all
1330 other resource files.
1331 It can be used to specify settings that are not understood by other
1333 implementations, for example.
1334 This variable is only honoured when defined in a resource file, e.g.,
1336 .Sx "INTERNAL VARIABLES" .
1340 The content of these files is interpreted as follows:
1343 .Bl -bullet -compact
1345 A lines' leading whitespace is removed.
1347 Empty lines are ignored.
1349 Any other line is interpreted as a command.
1350 It may be spread over multiple input lines if the newline character is
1352 by placing a reverse solidus character
1354 as the last character of the line; whereas any leading whitespace of
1355 follow lines is ignored, trailing whitespace before a escaped newline
1356 remains in the input.
1358 If the line (content) starts with the number sign
1360 then it is a comment-command \(en a real command! \(en and also ignored.
1361 This command is the only form of comment that is understood.
1365 Unless \*(UA is about to enter interactive mode syntax errors that occur
1366 while loading these files are treated as errors and cause program exit.
1367 More files with syntactically equal content can be
1369 The following, saved in a file, would be an examplary content:
1371 .Bd -literal -offset indent
1372 # This line is a comment command. And y\e
1373 es, it is really continued here.
1380 .\" .Ss "Character sets" {{{
1381 .Ss "Character sets"
1383 \*(OP \*(UA detects the character set of the terminal by using
1384 mechanisms that are controlled by the
1389 should give an overview); the \*(UA internal variable
1391 will be set to the detected terminal character set accordingly
1392 and will thus show up in the output of the commands
1398 However, a user supplied
1400 value is not overwritten by this detection mechanism: this
1402 must be used if the detection doesn't work properly,
1403 and it may be used to adjust the name of the locale character set.
1404 E.g., on BSD systems one may use a locale with the character set
1405 ISO8859-1, which is not a valid name for this character set; to be on
1406 the safe side, one may set
1408 to the correct name, which is ISO-8859-1.
1411 Note that changing the value doesn't mean much beside that,
1412 since several aspects of the real character set are implied by the
1413 locale environment of the system,
1414 and that stays unaffected by the content of an overwritten
1417 (This is mostly an issue when interactively using \*(UA, though.
1418 It is actually possible to send mail in a completely
1420 locale environment, an option that \*(UA's test-suite uses excessively.)
1423 If no character set conversion capabilities have been compiled into
1426 doesn't include the term
1430 will be the only supported character set,
1431 it is simply assumed that it can be used to exchange 8-bit messages,
1432 and the rest of this section does not apply;
1433 it may however still be necessary to explicitly set it if automatic
1434 detection fails, since in that case it defaults to the mentioned
1435 .\" (Keep in SYNC: ./nail.1:"Character sets", ./nail.h:CHARSET_*!)
1439 When reading messages, their text is converted into
1441 as necessary in order to display them on the users terminal.
1442 Unprintable characters and invalid byte sequences are detected
1443 and replaced by proper substitution characters (unless the variable
1445 was set once \*(UA was started).
1447 .Va charset-unknown-8bit
1448 to deal with another hairy aspect of message interpretation.
1451 When sending messages all their parts and attachments are classified.
1452 Whereas no character set conversion is performed on those parts which
1453 appear to be binary data,
1454 the character set being used must be declared within the MIME header of
1455 an outgoing text part if it contains characters that do not conform to
1456 the set of characters that are allowed by the email standards.
1457 Permissible values for character sets can be declared using the
1461 which defines a catch-all last-resort fallback character set that is
1462 implicitly appended to the list of character-sets in
1466 When replying to a message and the variable
1467 .Va reply-in-same-charset
1468 is set then the character set of the message being replied to is tried
1470 And it is also possible to make \*(UA work even more closely related to
1471 the current locale setting automatically by using the variable
1472 .Va sendcharsets-else-ttycharset ,
1473 please see there for more information.
1476 All the specified character sets are tried in order unless the
1477 conversion of the part or attachment succeeds.
1478 If none of the tried (8-bit) character sets is capable to represent the
1479 content of the part or attachment,
1480 then the message will not be sent and its text will optionally be
1484 In general, if the message
1485 .Dq Cannot convert from a to b
1486 appears, either some characters are not appropriate for the currently
1487 selected (terminal) character set,
1488 or the needed conversion is not supported by the system.
1489 In the first case, it is necessary to set an appropriate
1491 locale and/or the variable
1495 The best results are usually achieved when \*(UA is run in a UTF-8
1496 locale on a UTF-8 capable terminal, in which case the full Unicode
1497 spectrum of characters is available.
1498 In this setup characters from various countries can be displayed,
1499 while it is still possible to use more simple character sets for sending
1500 to retain maximum compatibility with older mail clients.
1503 On the other hand the POSIX standard defines a locale-independent 7-bit
1504 .Dq portable character set
1505 that should be used when overall portability is an issue, the even more
1506 restricted subset named
1507 .Dq portable filename character set
1508 consisting of A-Z, a-z, 0-9, period
1517 .\" .Ss "Message states" {{{
1518 .Ss "Message states"
1520 \*(UA differentiates in between several different message states;
1521 the current state will be reflected in header summary displays if
1523 is configured to do so (via the internal variable
1525 and messages can also be selected and be acted upon depending on their
1527 .Sx "Specifying messages" ) .
1528 When operating on the system
1530 box or in primary mailboxes opened with the special prefix
1534 special actions, like the automatic moving of messages to the secondary
1536 mailbox may be applied when the mailbox is left (also implicitly via
1537 a successful exit of \*(UA, but not if the special command
1539 is used) \(en however, because this may be irritating to users which
1542 mail-user-agents, the default global
1548 variables in order to suppress this behaviour.
1550 .Bl -tag -width ".It Ql _reserved"
1552 Message has neither been viewed nor moved to any other state.
1553 Such messages are retained even in the primary system mailbox.
1556 Message has neither been viewed nor moved to any other state, but the
1557 message was present already when the mailbox has been opened last:
1558 Such messages are retained even in the primary system mailbox.
1561 The message has been processed by one of the following commands:
1581 commands may also cause the next message to be marked as read, depending
1587 command is used, messages that are in the primary system mailbox or in
1588 mailboxes which were opened with the special
1592 state when the mailbox is left will be saved in
1599 The message has been processed by one of the following commands:
1605 can be used to access such messages.
1608 The message has been processed by a
1610 command and it will be retained in its current location.
1613 The message has been processed by one of the following commands:
1619 command is used, messages that are in the primary system mailbox or in
1620 mailboxes which were opened with the special
1624 state when the mailbox is left will be deleted; they will be saved in
1632 .\" .Ss "Specifying messages" {{{
1633 .Ss "Specifying messages"
1640 can be given a list of message numbers as arguments to apply to a number
1641 of messages at once.
1644 deletes messages 1 and 2,
1647 will delete the messages 1 through 5.
1648 In sorted or threaded mode (see the
1652 will delete the messages that are located between (and including)
1653 messages 1 through 5 in the sorted/threaded order, as shown in the
1656 Multiple colon modifiers can be joined into one, e.g.,
1658 The following special message names exist:
1660 .Bl -tag -width ".It Ar _n_u"
1666 All old messages (any not in state
1691 All answered messages
1696 All messages marked as draft.
1698 \*(OP All messages classified as spam.
1700 \*(OP All messages with unsure spam classification.
1702 The current message, the so-called
1705 The message that was previously the current message.
1707 The parent message of the current message,
1708 that is the message with the Message-ID given in the
1710 field or the last entry of the
1712 field of the current message.
1714 The next previous undeleted message,
1715 or the next previous deleted message for the
1718 In sorted/threaded mode,
1719 the next previous such message in the sorted/threaded order.
1721 The next undeleted message,
1722 or the next deleted message for the
1725 In sorted/threaded mode,
1726 the next such message in the sorted/threaded order.
1728 The first undeleted message,
1729 or the first deleted message for the
1732 In sorted/threaded mode,
1733 the first such message in the sorted/threaded order.
1736 In sorted/threaded mode,
1737 the last message in the sorted/threaded order.
1741 selects the message addressed with
1745 is any other message specification,
1746 and all messages from the thread that begins at it.
1747 Otherwise it is identical to
1752 the thread beginning with the current message is selected.
1757 All messages that were included in the message list for the previous
1760 .It Ar / Ns Ar string
1761 All messages that contain
1763 in the subject field (case ignored).
1770 the string from the previous specification of that type is used again.
1772 .It Xo Op Ar @ Ns Ar name-list Ns
1775 All messages that contain the given case-insensitive search
1777 ession; if the \*(OPal regular expression (see
1779 support is available
1781 will be interpreted as (an extended) one if any of the
1783 (extended) regular expression characters is seen.
1785 .Ar @ Ns Ar name-list
1786 part is missing, the search is restricted to the subject field body,
1789 specifies a comma-separated list of header fields to search, as in
1791 .Dl '@to,from,cc@Someone i ought to know'
1793 In order to search for a string that includes a
1795 (commercial at) character the
1797 is effectively non-optional, but may be given as the empty string.
1798 Some special header fields may be abbreviated:
1812 respectively and case-insensitively.
1817 can be used to search in (all of) the header(s) of the message, and the
1826 can be used to perform full text searches \(en whereas the former
1827 searches only the body, the latter also searches the message header.
1829 This message specification performs full text comparison, but even with
1830 regular expression support it is almost impossible to write a search
1831 expression that savely matches only a specific address domain.
1832 To request that the content of the header is treated as a list of
1833 addresses, and to strip those down to the plain email address which the
1834 search expression is to be matched against, prefix the header name
1835 (abbreviation) with a tilde
1838 .Dl @~f@@a\e.safe\e.domain\e.match$
1842 .Dq any substring matches
1845 header, which will match addresses (too) even if
1847 is set (and POSIX says
1848 .Dq any address as shown in a header summary shall be matchable in this form ) ;
1851 variable is set, only the local part of the address is evaluated
1852 for the comparison, not ignoring case, and the setting of
1854 is completely ignored.
1855 For finer control and match boundaries use the
1857 search expression; the \*(OPal IMAP-style
1859 expression can also be used if substring matches are desired.
1863 \*(OP IMAP-style SEARCH expressions may also be used.
1864 This addressing mode is available with all types of folders;
1865 \*(UA will perform the search locally as necessary.
1866 Strings must be enclosed by double quotes
1868 in their entirety if they contain white space or parentheses;
1869 within the quotes, only reverse solidus
1871 is recognized as an escape character.
1872 All string searches are case-insensitive.
1873 When the description indicates that the
1875 representation of an address field is used,
1876 this means that the search string is checked against both a list
1879 .Bd -literal -offset indent
1880 (\*qname\*q \*qsource\*q \*qlocal-part\*q \*qdomain-part\*q)
1885 and the addresses without real names from the respective header field.
1886 These search expressions can be nested using parentheses, see below for
1890 .Bl -tag -compact -width ".It Ar _n_u"
1891 .It Ar ( criterion )
1892 All messages that satisfy the given
1894 .It Ar ( criterion1 criterion2 ... criterionN )
1895 All messages that satisfy all of the given criteria.
1897 .It Ar ( or criterion1 criterion2 )
1898 All messages that satisfy either
1903 To connect more than two criteria using
1905 specifications have to be nested using additional parentheses,
1907 .Ql (or a (or b c)) ,
1911 .Ql ((a or b) and c) .
1914 operation of independent criteria on the lowest nesting level,
1915 it is possible to achieve similar effects by using three separate
1919 .It Ar ( not criterion )
1920 All messages that do not satisfy
1922 .It Ar ( bcc \*q Ns Ar string Ns Ar \*q )
1923 All messages that contain
1925 in the envelope representation of the
1928 .It Ar ( cc \*q Ns Ar string Ns Ar \*q )
1929 All messages that contain
1931 in the envelope representation of the
1934 .It Ar ( from \*q Ns Ar string Ns Ar \*q )
1935 All messages that contain
1937 in the envelope representation of the
1940 .It Ar ( subject \*q Ns Ar string Ns Ar \*q )
1941 All messages that contain
1946 .It Ar ( to \*q Ns Ar string Ns Ar \*q )
1947 All messages that contain
1949 in the envelope representation of the
1952 .It Ar ( header name \*q Ns Ar string Ns Ar \*q )
1953 All messages that contain
1958 .It Ar ( body \*q Ns Ar string Ns Ar \*q )
1959 All messages that contain
1962 .It Ar ( text \*q Ns Ar string Ns Ar \*q )
1963 All messages that contain
1965 in their header or body.
1966 .It Ar ( larger size )
1967 All messages that are larger than
1970 .It Ar ( smaller size )
1971 All messages that are smaller than
1975 .It Ar ( before date )
1976 All messages that were received before
1978 which must be in the form
1982 denotes the day of the month as one or two digits,
1984 is the name of the month \(en one of
1985 .Ql Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ,
1988 is the year as four digits, e.g.,
1992 All messages that were received on the specified date.
1993 .It Ar ( since date )
1994 All messages that were received since the specified date.
1995 .It Ar ( sentbefore date )
1996 All messages that were sent on the specified date.
1997 .It Ar ( senton date )
1998 All messages that were sent on the specified date.
1999 .It Ar ( sentsince date )
2000 All messages that were sent since the specified date.
2002 The same criterion as for the previous search.
2003 This specification cannot be used as part of another criterion.
2004 If the previous command line contained more than one independent
2005 criterion then the last of those criteria is used.
2009 .\" .Ss "On URL syntax and credential lookup" {{{
2010 .Ss "On URL syntax and credential lookup"
2012 \*(IN For accessing protocol-specific resources usage of Uniform
2013 Resource Locators (URL, RFC 1738) has become omnipresent.
2014 \*(UA expects and understands URLs in the following form;
2017 denote optional parts, optional either because there also exist other
2018 ways to define the information in question or because support of the
2019 part is protocol-specific (e.g.,
2021 is used by the IMAP protocol but not by POP3);
2026 are specified they must be given in URL percent encoded form (RFC 3986;
2034 .Dl PROTOCOL://[USER[:PASSWORD]@]server[:port][/path]
2037 Note that these \*(UA URLs most often don't conform to any real
2038 standard, but instead represent a normalized variant of RFC 1738 \(en
2039 they are not used in data exchange but only meant as a compact,
2040 easy-to-use way of defining and representing information in
2041 a well-known notation.
2044 Many internal variables of \*(UA exist in multiple versions, called
2045 variable chains for the rest of this document: the plain
2050 .Ql variable-USER@HOST .
2057 had been specified in the respective URL, otherwise it refers to the plain
2063 that had been found when doing the user chain lookup as is described
2066 will never be in URL percent encoded form, whether it came from an URL
2067 or not; i.e., values of
2068 .Sx "INTERNAL VARIABLES"
2069 must not be URL percent encoded.
2072 For example, whether an hypothetical URL
2073 .Ql smtp://hey%3Ayou@our.house
2074 had been given that includes a user, or whether the URL was
2075 .Ql smtp://our.house
2076 and the user had been found differently, to lookup the variable chain
2077 .Va smtp-use-starttls
2078 \*(UA first looks for whether
2079 .Ql smtp-\:use-\:starttls-\:hey:you@our.house
2080 is defined, then whether
2081 .Ql smtp-\:use-\:starttls-\:our.house
2082 exists before finally ending up looking at the plain variable itself.
2085 \*(UA obeys the following logic scheme when dealing with the
2086 necessary credential information of an account:
2092 has been given in the URL the variables
2096 are looked up; if no such variable(s) can be found then \*(UA will,
2097 when enforced by the \*(OPal variables
2098 .Va netrc-lookup-HOST
2105 specific entry which provides a
2107 name: this lookup will only succeed if unambiguous (one possible matching
2110 It is possible to load encrypted
2115 If there is still no
2117 then \*(UA will fall back to the user who is supposed to run \*(UA,
2118 the identity of which has been fixated during \*(UA startup and is
2119 known to be a valid user on the current host.
2122 Authentication: unless otherwise noted this will lookup the
2123 .Va PROTOCOL-auth-USER@HOST , PROTOCOL-auth-HOST , PROTOCOL-auth
2124 variable chain, falling back to a protocol-specific default should this
2130 has been given in the URL, then if the
2132 has been found through the \*(OPal
2134 that may have already provided the password, too.
2135 Otherwise the variable chain
2136 .Va password-USER@HOST , password-HOST , password
2137 is looked up and used if existent.
2139 Afterwards the complete \*(OPal variable chain
2140 .Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup
2144 cache is searched for a password only (multiple user accounts for
2145 a single machine may exist as well as a fallback entry without user
2146 but with a password).
2148 If at that point there is still no password available, but the
2149 (protocols') chosen authentication type requires a password, then in
2150 interactive mode the user will be prompted on the terminal.
2155 S/MIME verification works relative to the values found in the
2159 header field(s), which means that the values of
2160 .Va smime-sign , smime-sign-cert , smime-sign-include-certs
2162 .Va smime-sign-message-digest
2163 will not be looked up using the
2167 chains from above but instead use the corresponding values from the
2168 message that is being worked on.
2169 In unusual cases multiple and different
2173 combinations may therefore be involved \(en on the other hand those
2174 unusual cases become possible.
2175 The usual case is as short as:
2178 .Dl set mta=smtp://USER:PASS@HOST smtp-use-starttls \e
2179 .Dl \ \ \ \ smime-sign smime-sign-cert=+smime.pair
2184 contains complete example configurations.
2187 .\" .Ss "On terminal control and line editor" {{{
2188 .Ss "On terminal control and line editor"
2190 \*(OP Terminal control will be realized through one of the standard
2192 libraries, either the
2194 or, alternatively, the
2196 both of which will be initialized to work with the environment variable
2198 Terminal control will enhance or enable interactive usage aspects, e.g.,
2199 .Sx "Coloured display" ,
2200 and extend behaviour of the Mailx-Line-Editor (MLE), which may learn the
2201 byte-sequences of keys like the cursor and function keys, and which will
2202 automatically enter the so-called
2204 alternative screen shall the terminal support it.
2205 The internal variable
2207 can be used to overwrite settings or to learn (correct(ed)) keycodes.
2208 Actual interaction with the chosen library can be disabled completely by
2209 setting the internal variable
2210 .Va termcap-disable ;
2212 will be queried regardless, even if the \*(OPal support for the
2213 libraries has not been enabled at configuration time.
2216 \*(OP The builtin \*(UA Mailx-Line-Editor (MLE) should work in all
2217 environments which comply to the ISO C standard
2219 and will support wide glyphs if possible (the necessary functionality
2220 had been removed from ISO C, but was included in
2222 Prevent usage of a line editor in interactive mode by setting the
2224 .Va line-editor-disable .
2225 Especially if the \*(OPal terminal control support is missing setting
2226 entries in the internal variable
2228 will help shall the MLE misbehave, see there for more.
2229 The MLE can support a little bit of
2235 feature is available then input from line editor prompts will be saved
2236 in a history list that can be searched in and be expanded from.
2237 Such saving can be prevented by prefixing input with any amount of
2239 Aspects of history, like allowed content and maximum size, as well as
2240 whether history shall be saved persistently, can be configured with the
2244 .Va history-gabby-persist
2249 The MLE supports a set of editing and control commands.
2250 By default (as) many (as possible) of these will be assigned to a set of
2251 single-letter control codes, which should work on any terminal.
2254 command is available then the MLE commands can also be accessed freely
2255 by assigning the command name, which is shown in parenthesis in the list
2256 below, to any desired key-sequence, and the MLE will instead and also use
2258 to establish its builtin key bindings
2259 (more of them if the \*(OPal terminal control is available),
2260 an action which can then be suppressed completely by setting
2261 .Va line-editor-no-defaults .
2262 The following uses the
2264 ell-style quote notation that is documented in the introductional
2267 combinations not mentioned either cause job control signals or don't
2268 generate a (unique) keycode:
2272 .Bl -tag -compact -width "Ql _M"
2274 Go to the start of the line
2275 .Pf ( Cd mle-go-home ) .
2278 Move the cursor backward one character
2279 .Pf ( Cd mle-go-bwd ) .
2282 Forward delete the character under the cursor;
2283 quits \*(UA if used on the empty line unless the
2286 .Pf ( Cd mle-del-fwd ) .
2289 Go to the end of the line
2290 .Pf ( Cd mle-go-end ) .
2293 Move the cursor forward one character
2294 .Pf ( Cd mle-go-fwd ) .
2297 Cancel current operation, full reset.
2298 If there is an active history search or tabulator expansion then this
2299 command will first reset that, reverting to the former line content;
2300 thus a second reset is needed for a full reset in this case
2301 .Pf ( Cd mle-reset ) .
2304 Backspace: backward delete one character
2305 .Pf ( Cd mle-del-bwd ) .
2309 Horizontal tabulator:
2310 try to expand the word before the cursor, also supporting \*(UA
2313 .Pf ( Cd mle-complete ) .
2315 .Cd mle-quote-rndtrip .
2319 commit the current line
2320 .Pf ( Cd mle-commit ) .
2323 Cut all characters from the cursor to the end of the line
2324 .Pf ( Cd mle-snarf-end ) .
2328 .Pf ( Cd mle-repaint ) .
2331 \*(OP Go to the next history entry
2332 .Pf ( Cd mle-hist-fwd ) .
2339 \*(OP Go to the previous history entry
2340 .Pf ( Cd mle-hist-bwd ) .
2343 Toggle roundtrip mode shell quotes, where produced,
2345 .Pf ( Cd mle-quote-rndtrip ) .
2346 This setting is temporary, and will be forgotten once the command line
2350 \*(OP Complete the current line from (the remaining) older history entries
2351 .Pf ( Cd mle-hist-srch-bwd ) .
2354 \*(OP Complete the current line from (the remaining) newer history entries
2355 .Pf ( Cd mle-hist-srch-fwd ) .
2358 Paste the snarf buffer
2359 .Pf ( Cd mle-paste ) .
2366 .Pf ( Cd mle-snarf-line ) .
2369 Prompts for a Unicode character (its hexadecimal number) to be inserted
2370 .Pf ( Cd mle-prompt-char ) .
2371 Note this command needs to be assigned to a single-letter control code
2372 in order to become recognized and executed during input of
2373 a key-sequence (only four single-letter control codes can be used for
2374 that shortcut purpose); this control code is special-treated and can't
2375 be part of any other sequence, because any occurrence will perform the
2377 function immediately.
2380 Cut the characters from the one preceding the cursor to the preceding
2382 .Pf ( Cd mle-snarf-word-bwd ) .
2385 Move the cursor forward one word boundary
2386 .Pf ( Cd mle-go-word-fwd ) .
2389 Move the cursor backward one word boundary
2390 .Pf ( Cd mle-go-word-bwd ) .
2393 Escape: reset a possibly used multibyte character input state machine
2394 and \*(OPally a lingering, incomplete key binding
2395 .Pf ( Cd mle-cancel ) .
2396 This command needs to be assigned to a single-letter control code in
2397 order to become recognized and executed during input of a key-sequence
2398 (only four single-letter control codes can be used for that shortcut
2400 This control code may also be part of a multi-byte sequence, but if
2401 a sequence is active and the very control code is currently also an
2402 expected input, then it will first be consumed by the active sequence.
2417 Cut the characters from the one after the cursor to the succeeding word
2419 .Pf ( Cd mle-snarf-word-fwd ) .
2429 this will immediately reset a possibly active search etc.
2433 ring the audible bell.
2437 .\" .Ss "Coloured display" {{{
2438 .Ss "Coloured display"
2440 \*(OP \*(UA can be configured to support a coloured display and font
2441 attributes by emitting ANSI / ISO 6429 SGR (select graphic rendition)
2443 Usage of colours and font attributes solely depends upon the
2444 capability of the detected terminal type that is defined by the
2445 environment variable
2447 and which can be fine-tuned by the user via the internal variable
2451 On top of what \*(UA knows about the terminal the boolean variable
2453 defines whether the actually applicable colour and font attribute
2454 sequences should also be generated when output is going to be paged
2455 through the external program defined by the environment variable
2460 This is not enabled by default because different pager programs need
2461 different command line switches or other configuration in order to
2462 support those sequences.
2463 \*(UA however knows about some widely used pagers and in a clean
2464 environment it is often enough to simply set
2466 please refer to that variable for more on this topic.
2471 is set then any active usage of colour and font attribute sequences
2472 is suppressed, but without affecting possibly established
2477 To define and control colours and font attributes a single multiplexer
2478 command family exists:
2480 shows or defines colour mappings for the given colour type (e.g.,
2483 can be used to remove mappings of a given colour type.
2484 Since colours are only available in interactive mode, it may make
2485 sense to conditionalize the colour setup by encapsulating it with
2488 .Bd -literal -offset indent
2489 if terminal && $features =@ +colour
2490 colour iso view-msginfo ft=bold,fg=green
2491 colour iso view-header ft=bold,fg=red "from,subject"
2492 colour iso view-header fg=red
2494 uncolour iso view-header from,subject
2495 colour iso view-header ft=bold,fg=magenta,bg=cyan
2496 colour 256 view-header ft=bold,fg=208,bg=230 subject,from
2497 colour mono view-header ft=bold
2498 colour mono view-header ft=bold,ft=reverse subject,from
2502 .\" }}} (DESCRIPTION)
2505 .\" .Sh COMMANDS {{{
2508 Each command is typed on a line by itself,
2509 and may take arguments following the command word.
2510 Command names may be abbreviated, in which case the first command that
2511 matches the given prefix will be used.
2514 can be used to show the list of all commands, either alphabetically
2515 sorted or in prefix search order (these don't match, also because the
2516 POSIX standard prescribes a set of abbreviations); a more verbose
2517 listing will be produced if either of
2522 \*(OPally the command
2526 when given an argument, will show a documentation string for the
2527 command matching the expanded argument, as in
2529 which should be a shorthand of
2533 For commands which take message lists as arguments, the next message
2534 forward that satisfies the command's requirements will be used shall no
2535 explicit message list have been specified.
2536 If there are no messages forward of the current message,
2537 the search proceeds backwards,
2538 and if there are no good messages at all,
2539 \*(UA shows an error message and aborts the command.
2540 \*(ID Non-message-list arguments can be quoted using the following methods:
2543 .Bl -bullet -compact -offset indent
2545 An argument can be enclosed between paired double-quotes
2550 any white space, shell word expansion, or reverse solidus characters
2551 (except as described next) within the quotes are treated literally as
2552 part of the argument.
2553 A double-quote will be treated literally within single-quotes and vice
2555 Inside such a quoted string the actually used quote character can be
2556 used nonetheless by escaping it with a reverse solidus
2562 An argument that is not enclosed in quotes, as above, can usually still
2563 contain space characters if those spaces are reverse solidus escaped, as in
2567 A reverse solidus outside of the enclosing quotes is discarded
2568 and the following character is treated literally as part of the argument.
2573 Some commands which don't take message-list arguments can also be
2574 prefixed with the special keyword
2576 to choose \*(INible behaviour, and some new commands support only the
2577 new quoting style (without that keyword) and are flagged \*(NQ.
2578 In the future \*(UA will (mostly) use
2580 compatible argument parsing:
2581 Non-message-list arguments can be quoted using the following shell-style
2582 mechanisms: the escape character, single-quotes, double-quotes and
2583 dollar-single-quotes; any unquoted number sign
2585 starts a comment that ends argument processing.
2586 The overall granularity of error reporting and diagnostics, also
2587 regarding function arguments and their content, will improve.
2591 .Bl -bullet -compact -offset indent
2593 The literal value of any character can be preserved by preceding it
2594 with the escape character reverse solidus
2598 will cause variable expansion of the given name: \*(UA
2599 .Sx "INTERNAL VARIABLES"
2602 (shell) variables can be accessed through this mechanism, brace
2603 enclosing the name is supported.
2606 Arguments which are enclosed in
2607 .Ql 'single-\:quotes'
2608 retain their literal value.
2609 A single-quote cannot occur within single-quotes.
2612 The literal value of all characters enclosed in
2613 .Ql \(dqdouble-\:quotes\(dq
2614 is retained, with the exception of dollar
2616 which will cause variable expansion, as above, backquote (grave accent)
2618 (which not yet means anything special), reverse solidus
2620 which will escape any of the characters dollar
2622 (to prevent variable expansion), backquote (grave accent)
2626 (to prevent ending the quote) and reverse solidus
2628 (to prevent escaping, i.e., to embed a reverse solidus character as-is),
2629 but has no special meaning otherwise.
2632 Arguments enclosed in
2633 .Ql $'dollar-\:single-\:quotes'
2634 extend normal single quotes in that reverse solidus escape sequences are
2635 expanded as follows:
2637 .Bl -tag -compact -width "Ql \eNNN"
2643 an escape character.
2645 an escape character.
2657 emits a reverse solidus character.
2661 double quote (escaping is optional).
2663 eight-bit byte with the octal value
2665 (one to three octal digits), optionally with an additional
2668 A 0 byte will suppress further output for the quoted argument.
2670 eight-bit byte with the hexadecimal value
2672 (one or two hexadecimal characters).
2673 A 0 byte will suppress further output for the quoted argument.
2675 the Unicode / ISO-10646 character with the hexadecimal codepoint value
2677 (one to eight hexadecimal digits) \(em note that Unicode defines the
2678 maximum codepoint to be ever supported as
2683 This escape is only supported in locales which support Unicode (see
2684 .Sx "Character sets" ) ,
2685 in other cases the sequence will remain unexpanded unless the given code
2686 point is ASCII compatible or can be represented in the current locale.
2687 The character NUL will suppress further output for the quoted argument.
2691 except it takes only one to four hexadecimal digits.
2696 This is a mechanism that allows usage of the non-printable (ASCII and
2697 compatible) control codes 0 to 31: to be able to create a printable
2698 representation the numeric value 64 is added to the control code of
2699 desire, and the resulting ASCII character set code point is then
2700 printed, e.g., BEL is
2701 .Ql 7 + 64 = 71 = G .
2702 Often circumflex notation is used for the visualization purpose, e.g,
2704 but the reverse solid notation has been standardized:
2706 The control code NUL
2708 ends argument processing without producing further output.
2710 Non-standard extension: expand the given variable name, as above.
2711 Brace enclosing the name is supported.
2713 Not yet supported, just to raise awareness: Non-standard extension.
2719 .Sy Compatibility notes:
2720 \*(ID Note these are new mechanisms which are not supported by all
2722 Round-tripping (feeding in things shown in list modes again) are not yet
2723 stable or possible at all.
2724 On new-style command lines it is wise to quote semicolon
2728 characters in order to ensure upward compatibility: the author would
2729 like to see things like
2730 .Ql ? echo $'trouble\etahead' | cat >> in_the_shell.txt
2732 .Ql ? top 2 5 10; type 3 22
2734 Before \*(UA will switch entirely to shell-style argument parsing there
2735 will be a transition phase where using
2737 will emit obsoletion warnings.
2738 E.g., the following are equivalent:
2740 .Bd -literal -offset indent
2741 mlist @any\e\e.where\e\e.example\e\e.com
2742 wysh mlist '@any\e.where\e.example\e.com' # This is a comment
2743 wysh mlist $'@any\e\e\ex2Ewhere\e\e.example\e\e\e56com' # A comment
2744 wysh mlist "@any\e.where\e.example\e.com"
2748 In any event an unquoted reverse solidus at the end of a command line is
2749 discarded and the next line continues the command.
2750 \*(ID Note that line continuation is handled before the above parsing is
2751 applied, i.e., the parsers documented above will see merged lines.
2752 Filenames, where expected, are subsequently subjected to the following
2753 transformations, in sequence:
2756 .Bl -bullet -compact -offset indent
2758 If the filename begins with an unquoted plus sign, and the
2760 variable is defined,
2761 the plus sign will be replaced by the value of the
2763 variable followed by a solidus.
2766 variable is unset or is set to null, the filename will be unchanged.
2769 Meta expansions are applied to the filename: a leading tilde
2771 character will be replaced by the expansion of
2773 except when followed by a valid user name, in which case the home
2774 directory of the given user is used instead.
2779 will be replaced by the expansion of the variable, if possible; \*(UA
2780 .Sx "INTERNAL VARIABLES"
2783 (shell) variables can be accessed through this mechanism, and the usual
2784 escape mechanism has to be applied to prevent interpretation.
2785 If the fully expanded filename results in multiple pathnames and the
2786 command is expecting only one file, an error results.
2788 In interactive context, in order to allow simple value acceptance (via
2790 arguments will usually be displayed in a properly quoted form, e.g., a file
2791 .Ql diet\e is \ecurd.txt
2793 .Ql 'diet\e is \ecurd.txt' .
2797 The following commands are available:
2799 .Bl -tag -width ".Ic _ccount"
2806 ) command which follows.
2810 The comment-command causes the entire line to be ignored.
2812 this really is a normal command which' purpose is to discard its
2815 indicating special character, which means that, e.g., trailing comments
2816 on a line are not possible.
2820 Goes to the next message in sequence and types it
2826 Display the preceding message, or the n'th previous message if given
2827 a numeric argument n.
2831 Show the current message number (the
2836 Show a brief summary of commands.
2837 \*(OP Given an argument a synopsis for the command in question is
2838 shown instead; commands can be abbreviated in general and this command
2839 can be used to see the full expansion of an abbreviation including the
2840 synopsis, try, e.g.,
2845 and see how the output changes.
2855 Interprets the remainder of the word as a macro name and passes it
2860 is a shorter synonym for
2861 .Ql call Ar mymacro .
2865 (ac) Creates, selects or lists (an) account(s).
2866 Accounts are special incarnations of
2868 macros and group commands and variable settings which together usually
2869 arrange the environment for the purpose of creating an email account.
2870 Different to normal macros settings which are covered by
2872 \(en here by default enabled! \(en will not be reverted before the
2877 (case-insensitive) always exists, and all but it can be deleted via
2880 Without arguments a listing of all defined accounts is shown.
2881 With one argument the given account is activated: the system
2883 box of that account will be activated (as via
2885 and a possibly installed
2888 The two argument form is identical to defining a macro as via
2890 .Bd -literal -offset indent
2892 set folder=~/mail MAIL=+syste.mbox record=+sent.mbox
2893 set from='myname@myisp.example (My Name)'
2894 set mta=smtp://mylogin@smtp.myisp.example
2900 (a) With no arguments, shows all currently-defined aliases.
2901 With one argument, shows that alias.
2902 With more than one argument,
2903 creates a new alias or appends to an existing one.
2905 can be used to delete aliases.
2909 (alt) Manage a list of alternate addresses / names of the active user,
2910 members of which will be removed from recipient lists when replying to
2913 variable is not set).
2914 If arguments are given the set of alternate names is replaced by them,
2915 without arguments the current set is displayed.
2919 Takes a message list and marks each message as having been answered.
2920 This mark has no technical meaning in the mail system;
2921 it just causes messages to be marked in the header summary,
2922 and makes them specially addressable.
2927 \*(OP\*(NQ The bind command extends the MLE (see
2928 .Sx "On terminal control and line editor" )
2929 with freely configurable key bindings.
2930 With one argument all bindings for the given context are shown,
2931 specifying an asterisk
2933 will show the bindings of all contexts; a more verbose listing will be
2934 produced if either of
2939 With two or more arguments a binding is (re)established:
2940 the first argument is the context to which the binding shall apply,
2941 the second argument is a comma-separated list of the
2943 which form the binding, and any remaining arguments form the expansion.
2944 To indicate that a binding shall not be auto-committed, but that the
2945 expansion shall instead be furtherly editable by the user, an at-sign
2947 (that will be removed) can be placed last in the expansion, from which
2948 leading and trailing whitespace will finally be removed.
2951 Contexts define when a binding applies, i.e., a binding won't be seen
2952 unless the context for which it is defined for is currently active.
2953 This is not true for the binding
2955 which always applies, but which will be searched secondarily to a more
2956 specialized context and may thus have some or all of its key bindings
2957 transparently replaced by equal bindings of more specialized contexts.
2958 The available contexts are
2960 which always applies, and
2962 which applies to compose-mode.
2966 which form the binding are specified as a comma-separated list of
2967 byte-sequences, where each list entry corresponds to one key(press).
2968 \*(OPally a list entry may, indicated by a leading colon character
2970 also refer to the name of a terminal capability;
2971 several dozen names will be compiled into \*(UA and may be specified
2974 or, if existing, by their
2976 name, regardless of the actually used terminal control library.
2977 It is however possible to use any capability, as long as the name is
2978 resolvable by the control library or defined in the internal variable
2980 Input sequences are not case-normalized, so that an exact match is
2981 required to update or remove a binding.
2984 .Bd -literal -offset indent
2985 bind base $'\eE',d mle-snarf-word-fwd # Esc(ape)
2986 bind base $'\eE',$'\ec?' mle-snarf-word-bwd # Esc, Delete
2987 bind compose :kf1 ~e
2988 bind base $'\ecA',:khome,w 'echo An editable binding@'
2989 bind base a,b,c rm -rf / @ # Another editable binding
2993 Note that the entire comma-separated list is first parsed (over) as a
2994 shell-token with whitespace as the field separator, before being parsed
2995 and expanded for real with comma as the field separator, therefore
2996 whitespace needs to be properly quoted:
2997 shell-style quoting is documented in the introductional section of
2999 Using Unicode reverse solidus escape sequences renders a binding
3000 defunctional if the locale doesn't support Unicode (see
3001 .Sx "Character sets" ) ,
3002 and using terminal capabilities does so if no terminal control support
3003 is (currently) available.
3006 The following terminal capability names are builtin and can be used in
3008 or (if available) the two-letter
3010 notation regardless of the actually used library.
3011 See the respective manual for a list of capabilities.
3014 can be used to show all the capabilities of
3016 or the given terminal type;
3019 flag will also show supported (non-standard) extensions.
3022 .Bl -tag -compact -width kcuuf_or_kcuuf
3023 .It Cd kbs Ns \0or Cd kb
3025 .It Cd kdch1 Ns \0or Cd kD
3027 .It Cd kDC Ns \0or Cd *4
3028 \(em shifted variant.
3029 .It Cd kel Ns \0or Cd kE
3030 Clear to end of line.
3031 .It Cd kext Ns \0or Cd @9
3033 .It Cd kich1 Ns \0or Cd kI
3035 .It Cd kIC Ns \0or Cd #3
3036 \(em shifted variant.
3037 .It Cd khome Ns \0or Cd kh
3039 .It Cd kHOM Ns \0or Cd #2
3040 \(em shifted variant.
3041 .It Cd kend Ns \0or Cd @7
3043 .It Cd knp Ns \0or Cd kN
3045 .It Cd kpp Ns \0or Cd kP
3047 .It Cd kcub1 Ns \0or Cd kl
3048 Left cursor (with more modifiers: see below).
3049 .It Cd kLFT Ns \0or Cd #4
3050 \(em shifted variant.
3051 .It Cd kcuf1 Ns \0or Cd kr
3052 Right cursor (ditto).
3053 .It Cd kRIT Ns \0or Cd %i
3054 \(em shifted variant.
3055 .It Cd kcud1 Ns \0or Cd kd
3056 Down cursor (ditto).
3058 \(em shifted variant (only terminfo).
3059 .It Cd kcuu1 Ns \0or Cd ku
3062 \(em shifted variant (only terminfo).
3063 .It Cd kf0 Ns \0or Cd k0
3065 Add one for each function key up to
3070 .It Cd kf10 Ns \0or Cd k;
3072 .It Cd kf11 Ns \0or Cd F1
3074 Add one for each function key up to
3082 Some terminals support key-modifier combination extensions, e.g.,
3084 For example, the delete key,
3086 in its shifted variant, the name is mutated to
3088 then a number is appended for the states
3100 .Ql Shift+Alt+Control
3102 The same for the left cursor key,
3104 .Cd KLFT , KLFT3 , KLFT4 , KLFT5 , KLFT6 , KLFT7 , KLFT8 .
3107 Key bindings can be removed with the command
3109 It is advisable to use an initial escape or other control character (e.g.,
3111 for bindings which describe user key combinations (as opposed to purely
3112 terminal capability based ones), in order to avoid ambiguities whether
3113 input belongs to key sequences or not; it also reduces search time.
3116 may help shall keys and sequences be falsely recognized.
3121 Calls a macro that has been created via
3126 (ch) Change the working directory to
3128 or the given argument.
3134 \*(OP Only applicable to S/MIME signed messages.
3135 Takes a message list and a file name and saves the certificates
3136 contained within the message signatures to the named file in both
3137 human-readable and PEM format.
3138 The certificates can later be used to send encrypted messages to the
3139 respective message senders by setting
3140 .Va smime-encrypt-USER@HOST
3145 (ch) Change the working directory to
3147 or the given argument.
3153 Only applicable to threaded mode.
3154 Takes a message list and makes all replies to these messages invisible
3155 in header summaries, unless they are in state
3161 \*(OP\*(NQ Manage colour mappings for the type of colour given as the
3162 (case-insensitive) first argument, which must be one of
3164 for 256-colour terminals,
3169 for the standard 8-colour ANSI / ISO 6429 color palette and
3173 for monochrome terminals.
3174 Monochrome terminals cannot deal with colours, but only (some) font
3178 Without further arguments the list of all currently defined mappings
3179 for the given colour type is shown (as a special case giving
3183 will iterate over all types in order).
3184 Otherwise the second argument defines the mappable slot, the third
3185 argument a (comma-separated list of) colour and font attribute
3186 specification(s), and the optional fourth argument can be used to
3187 specify a precondition: if conditioned mappings exist they are tested in
3188 (creation) order unless a (case-insensitive) match has been found, and
3189 the default mapping (if any has been established) will only be chosen as
3191 The types of precondition available depend on the mappable slot, the
3192 following of which exist:
3195 Mappings prefixed with
3197 are used for the \*(OPal builtin Mailx-Line-Editor (MLE, see
3198 .Sx "On terminal control and line editor" )
3199 and don't support preconditions.
3201 .Bl -tag -compact -width view-partinfo
3203 This mapping is used for the position indicator that is visible when
3204 a line cannot be fully displayed on the screen.
3211 Mappings prefixed with
3213 are used in header summaries, and they all understand the preconditions
3215 (the current message) and
3217 for elder messages (only honoured in conjunction with
3218 .Va datefield-markout-older ) .
3220 .Bl -tag -compact -width view-partinfo
3222 This mapping is used for the
3224 that can be created with the
3228 formats of the variable
3231 For the complete header summary line except the
3233 and the thread structure.
3235 For the thread structure which can be created with the
3237 format of the variable
3242 Mappings prefixed with
3244 are used when displaying messages.
3246 .Bl -tag -compact -width view-partinfo
3248 This mapping is used for so-called
3250 lines, which are MBOX file format specific header lines.
3253 A comma-separated list of headers to which the mapping applies may be
3254 given as a precondition; if the \*(OPal regular expression support is
3255 available then if any of the
3257 (extended) regular expression characters is seen the precondition will
3258 be evaluated as (an extended) one.
3260 For the introductional message info line.
3261 .It Cd view-partinfo
3262 For MIME part info lines.
3266 The following (case-insensitive) colour definitions and font attributes
3267 are understood, multiple of which can be specified in a comma-separated
3277 It is possible (and often applicable) to specify multiple font
3278 attributes for a single mapping.
3281 foreground colour attribute:
3291 To specify a 256-color mode a decimal number colour specification in
3292 the range 0 to 255, inclusive, is supported, and interpreted as follows:
3294 .Bl -tag -compact -width "999 - 999"
3296 the standard ISO 6429 colors, as above.
3298 high intensity variants of the standard colors.
3300 216 colors in tuples of 6.
3302 grayscale from black to white in 24 steps.
3304 .Bd -literal -offset indent
3306 fg() { printf "\e033[38;5;${1}m($1)"; }
3307 bg() { printf "\e033[48;5;${1}m($1)"; }
3309 while [ $i -lt 256 ]; do fg $i; i=$(($i + 1)); done
3310 printf "\e033[0m\en"
3312 while [ $i -lt 256 ]; do bg $i; i=$(($i + 1)); done
3313 printf "\e033[0m\en"
3317 background colour attribute (see
3319 for possible values).
3323 Mappings may be removed with the command
3325 For a generic overview see the section
3326 .Sx "Coloured display" .
3331 (C) Copy messages to files whose names are derived from the author of
3332 the respective message and don't mark them as being saved;
3333 otherwise identical to
3338 (c) Copy messages to the named file and don't mark them as being saved;
3339 otherwise identical to
3344 \*(NQ With no arguments, shows all currently-defined custom headers.
3345 With one argument, shows that custom header.
3346 With more than one argument, creates a new or replaces an existing
3347 custom header with the name given as the first argument, the content of
3348 which being defined by the concatenated remaining arguments.
3350 can be used to delete custom headers.
3351 \*(ID Overwriting of automatically managed headers is neither supported
3353 Defined custom headers will be injected into newly composed or forwarded
3356 .Dl customhdr OpenPGP id=12345678; url=http://www.YYY.ZZ
3360 may also be used to inject custom headers; it is covered by
3365 Show the name of the current working directory.
3369 \*(OP For unencrypted messages this command is identical to
3371 Encrypted messages are first decrypted, if possible, and then copied.
3375 \*(OP For unencrypted messages this command is identical to
3377 Encrypted messages are first decrypted, if possible, and then copied.
3381 Without arguments the current list of macros, including their content,
3382 is shown, otherwise a macro is defined.
3383 A macro definition is a sequence of commands in the following form:
3384 .Bd -literal -offset indent
3393 A defined macro can be invoked explicitly by using the
3397 commands, or implicitly if a macro hook is triggered, e.g., a
3399 Note that interpretation of
3401 depends on how (i.e.,
3403 normal macro, folder hook, hook, account switch) the macro is invoked.
3404 Macros can be deleted via
3408 Macro behaviour, including option localization, will change in v15.
3409 Please be aware of that and possibly embed a version check in a resource
3414 (d) Marks the given message list as
3416 Deleted messages will neither be saved in
3418 nor will they be available for most other commands.
3430 Deletes the current message and displays the next message.
3431 If there is no next message, \*(UA says
3438 up or down by one message when given
3442 argument, respectively.
3446 Takes a message list and marks each given message as a draft.
3447 This mark has no technical meaning in the mail system;
3448 it just causes messages to be marked in the header summary,
3449 and makes them specially addressable.
3453 (ec) Echoes its arguments after applying
3455 expansions and filename transformations, as documented for
3460 (e) Point the text editor (as defined in
3462 at each message from the given list in turn.
3463 Modified contents are discarded unless the
3470 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3471 conditional \(em if the condition of a preceding
3473 was false, check the following condition and execute the following block
3474 if it evaluates true.
3479 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3480 conditional \(em if none of the conditions of the preceding
3484 commands was true, the
3490 (en) Marks the end of an
3491 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3492 conditional execution block.
3497 \*(NQ \*(UA has a strict notion about which variables are
3498 .Sx "INTERNAL VARIABLES"
3499 and which are managed in the program
3501 Since some of the latter are a vivid part of \*(UAs functioning,
3502 however, they are transparently integrated into the normal handling of
3503 internal variables via
3507 To integrate other environment variables of choice into this
3508 transparent handling, and also to export internal variables into the
3509 process environment where they normally are not, a
3511 needs to become established with this command, as in, e.g.,
3514 .Dl environ link PERL5LIB from TZ
3517 Afterwards changing such variables with
3519 will cause automatic updates of the program environment, and therefore
3520 be inherited by newly created child processes.
3521 Sufficient system support provided (it was in BSD as early as 1987, and
3522 is standardized since Y2K) removing such variables with
3524 will remove them also from the program environment, but in any way
3525 the knowledge they ever have been
3528 Note this implies that
3530 may cause loss of links.
3535 will remove an existing link, but leaves the variables as such intact.
3536 Additionally the subcommands
3540 are provided, which work exactly the same as the documented commands
3544 but (additionally) link the variable(s) with the program environment and
3545 thus immediately export them to, or remove them from (if possible),
3546 respectively, the program environment.
3551 \*(OP Since \*(UA uses the console as a user interface it can happen
3552 that messages scroll by too fast to become recognized.
3553 Optionally an error message ring queue is available which stores
3554 duplicates of any error message and notifies the user in interactive
3555 sessions whenever a new error has occurred.
3556 The queue is finite: if its maximum size is reached any new message
3557 replaces the eldest.
3560 can be used to manage this message queue: if given
3562 or no argument the queue will be displayed and cleared,
3564 will only clear all messages from the queue.
3568 (ex or x) Exit from \*(UA without changing the active mailbox and skip
3569 any saving of messages in
3571 as well as a possibly tracked line editor history file.
3577 but open the mailbox readonly.
3581 (fi) The file command switches to a new mailbox.
3582 Without arguments it shows status information of the current mailbox.
3583 If an argument is given, it will write out changes (such as deletions)
3584 the user has made and open a new mailbox.
3585 Some special conventions are recognized for the
3589 .Bl -tag -compact -offset indent -width ".Ar %:__lespec"
3591 (number sign) means the previous file,
3593 (percent sign) means the invoking user's system
3597 means the primary system mailbox of
3599 (and never the value of
3601 regardless of its actual setting),
3603 (ampersand) means the invoking user's
3613 expands to the same value as
3615 but the file is handled as a primary system mailbox by, e.g., the
3619 commands, meaning that messages that have been read in the current
3620 session will be moved to the
3622 mailbox instead of simply being flagged as read.
3625 If the name matches one of the strings defined with the command
3627 it is replaced by its long form and expanded.
3628 If the name ends with
3633 it is treated as being compressed with
3638 respectively, and transparently handled through an intermediate
3639 (un)compression step (using a temporary file) with the according
3640 facility, sufficient support provided.
3641 Likewise, if the named file doesn't exist, but a file with one of the
3642 mentioned compression extensions does, then the name is automatically
3643 expanded and the compressed file is used.
3645 Otherwise, if the name ends with an extension for which
3646 .Va file-hook-load-EXTENSION
3648 .Va file-hook-save-EXTENSION
3649 variables are set, then the given hooks will be used to load and save
3651 and \*(UA will work with an intermediate temporary file.
3653 MBOX files (flat file-based mailboxes) are generally locked during file
3654 operations in order to avoid inconsistencies due to concurrent
3656 \*(OPal Mailbox files which \*(UA treats as system
3658 boxes or primary mailboxes will also be protected by so-called dotlock
3659 files, the traditional way of mail spool file locking: for any file
3663 will be created for the duration of the synchronization \(em
3664 as necessary a privilege-separated dotlock child process will be used
3665 to accommodate for necessary privilege adjustments in order to create
3666 the dotlock file in the same directory
3667 and with the same user and group identities as the file of interest.
3670 for fine-tuning the handling of MBOX files.
3674 refers to a directory with the subdirectories
3679 then it is treated as a folder in
3681 format; \*(ID the variable
3683 can be used to control the format of yet non-existent folders.
3686 .Dl \*(IN protocol://[user[:password]@]host[:port][/path]
3687 .Dl \*(OU protocol://[user@]host[:port][/path]
3689 is taken as an Internet mailbox specification.
3690 The \*(OPally supported protocols are
3694 (POP3 with SSL/TLS encrypted transport).
3697 part is valid only for IMAP; there it defaults to
3699 Also see the section
3700 .Sx "On URL syntax and credential lookup" .
3704 contains special characters, in particular
3708 they must be escaped in URL notation \(en the command
3710 can be used to show the necessary conversion.
3714 Takes a message list and marks the messages as
3716 ged for urgent/special attention.
3717 This mark has no technical meaning in the mail system;
3718 it just causes messages to be highlighted in the header summary,
3719 and makes them specially addressable.
3728 With no arguments, list the names of the folders in the folder directory.
3729 With an existing folder as an argument,
3730 lists the names of folders below the named folder.
3736 but saves the message in a file named after the local part of the first
3737 recipient's address (instead of in
3744 but saves the message in a file named after the local part of the first
3745 recipient's address (instead of in
3752 but responds to all recipients regardless of the
3757 .It Ic followupsender
3760 but responds to the sender only regardless of the
3776 (f) Takes a list of message specifications and displays a summary of
3777 their message headers, exactly as via
3779 An alias of this command is
3782 .Sx "Specifying messages" .
3788 but saves the message in a file named after the local part of the
3789 recipient's address (instead of in
3794 Takes a message and the address of a recipient
3795 and forwards the message to him.
3796 The text of the original message is included in the new one,
3797 with the value of the
3799 variable preceding it.
3804 commands specify which header fields are included in the new message.
3805 Only the first part of a multipart message is included unless the
3806 .Va forward-as-attachment
3810 is set recipient addresses will be stripped from comments, names etc.
3814 Specifies which header fields are to be ignored with the command
3816 This command has no effect when the
3817 .Va forward-as-attachment
3822 Specifies which header fields are to be retained with the command
3827 This command has no effect when the
3828 .Va forward-as-attachment
3833 Define or list command aliases, so-called ghosts.
3834 Without arguments a list of all currently known aliases is shown.
3835 With one argument the expansion of the given alias is shown.
3836 With two or more arguments a command alias is defined or updated: the
3837 first argument is the name under which the remaining command line should
3838 be accessible, the content of which can be just about anything.
3839 A ghost can be used everywhere a normal command can be used, but always
3840 takes precedence; any arguments that are given to the command alias are
3841 joined onto the alias content, and the resulting string forms the
3842 command line that is, in effect, executed.
3845 .Bd -literal -offset indent
3847 `ghost': no such alias: "xx"
3850 ghost xx "echo hello,"
3859 (h) Show the current group of headers, the size of which depends on
3862 and the style of which can be adjusted with the variable
3864 If a message-specification is given the group of headers containing the
3865 first message therein is shown and the message at the top of the screen
3880 the list of history entries;
3883 argument selects and shows the respective history entry \(en
3886 to accept it, and the history entry will become the new history top.
3887 The default mode if no arguments are given is
3894 Takes a message list and marks each message therein to be saved in the
3899 Does not override the
3902 \*(UA deviates from the POSIX standard with this command, because a
3904 command issued after
3906 will display the following message, not the current one.
3911 (i) Part of the nestable
3912 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3913 conditional execution construct \(em if the given condition is true then
3914 the encapsulated block is executed.
3915 POSIX only supports the (case-insensitive) conditions
3920 end, all remaining conditions are non-portable extensions; note that
3921 falsely specified conditions cause the execution of the entire
3922 conditional construct until the (matching) closing
3924 command to be suppressed.
3925 The syntax of the nestable
3927 conditional execution construct requires that each condition and syntax
3928 element is surrounded by whitespace.
3930 .Bd -literal -offset indent
3939 The (case-insensitive) condition
3941 erminal will evaluate to true if the standard input is a terminal, i.e.,
3942 in interactive sessions.
3943 Another condition can be any boolean value (see the section
3944 .Sx "INTERNAL VARIABLES"
3945 for textual boolean representations) to mark an enwrapped block as
3948 .Dq always execute .
3949 It is possible to check
3950 .Sx "INTERNAL VARIABLES"
3953 variables for existence or compare their expansion against a user given
3954 value or another variable by using the
3956 .Pf ( Dq variable next )
3957 conditional trigger character;
3958 a variable on the right hand side may be signalled using the same
3960 The variable names may be enclosed in a pair of matching braces.
3963 The available comparison operators are
3967 (less than or equal to),
3973 (greater than or equal to),
3977 (is substring of) and
3979 (is not substring of).
3980 The values of the left and right hand side are treated as strings and
3981 are compared 8-bit byte-wise, ignoring case according to the rules of
3982 the US-ASCII encoding (therefore, dependent on the active locale,
3983 possibly producing false results for strings in the locale encoding).
3984 Except for the substring checks the comparison will instead be performed
3985 arithmetically if both, the user given value as well as the variable
3986 content, can be parsed as numbers (integers).
3987 An unset variable is treated as the empty string.
3990 When the \*(OPal regular expression support is available, the additional
3996 They treat the right hand side as an extended regular expression that is
3997 matched case-insensitively and according to the active
3999 locale, meaning that strings in the locale encoding should be matched
4003 Conditions can be joined via AND-OR lists (where the AND operator is
4005 and the OR operator is
4007 which have equal precedence and will be evaluated with left
4008 associativity, thus using the same syntax that is known for the
4010 It is also possible to form groups of conditions and lists by enclosing
4011 them in pairs of brackets
4012 .Ql [\ \&.\&.\&.\ ] ,
4013 which may be interlocked within each other, and also be joined via
4017 The results of individual conditions and entire groups may be modified
4018 via unary operators: the unary operator
4020 will reverse the result.
4022 .Bd -literal -offset indent
4026 if $ttycharset == "UTF-8"
4027 echo *ttycharset* is set to UTF-8, case-insensitively
4031 echo These two variables are equal
4033 if $version-major >= 15
4034 echo Running a new version..
4035 if $features =@ +regex
4036 if $TERM =~ "^xterm\&.*"
4037 echo ..in an X terminal
4040 if [ [ true ] && [ [ ${debug} ] || [ $verbose ] ] ]
4043 if true && $debug || ${verbose}
4044 echo Left associativity, as is known from the shell
4046 if ! ! true && ! [ ! $debug && ! $verbose ]
4047 echo Unary operator support
4055 Without arguments the list of ignored header fields is shown,
4056 otherwise the given list of header fields is added to the ignore list:
4057 Header fields in the ignore list are not shown on the terminal when
4058 a message is displayed.
4059 To display a message in its entirety, use the commands
4070 Shows the names of all available commands, alphabetically sorted.
4071 If given any non-whitespace argument the list will be shown in the order
4072 in which command prefixes are searched.
4075 output is available.
4079 This command can be used to localize changes to variables, meaning that
4080 their state will be reverted to the former one once the covered scope
4082 It can only be used inside of macro definition blocks introduced by
4086 and is interpreted as a boolean (string, see
4087 .Sx "INTERNAL VARIABLES" ) ;
4090 of an account is left once it is switched off again.
4091 .Bd -literal -offset indent
4092 define temporary_settings {
4107 enables change localization and calls
4109 which explicitly resets localization, then any value changes within
4111 will still be reverted by
4113 \*(ID Once the outermost level, the one which enabled localization
4114 first, is left, but no earlier, all adjustments will be unrolled.
4115 \*(ID Likewise worth knowing, if in this example
4117 changes to a different
4119 which sets some variables that are yet covered by localizations, their
4120 scope will be extended, and in fact leaving the
4122 will (thus) restore settings in (likely) global scope which actually
4123 were defined in a local, private context.
4127 Reply to messages that come in via known
4130 .Pf ( Ic mlsubscribe )
4131 mailing lists, or pretend to do so (see
4132 .Sx "Mailing lists" ) :
4135 functionality this will actively resort and even remove message
4136 recipients in order to generate a message that is supposed to be sent to
4138 For example it will also implicitly generate a
4139 .Ql Mail-Followup-To:
4140 header if that seems useful, regardless of the setting of the variable
4147 but saves the message in a file named after the local part of the first
4148 recipient's address (instead of in
4153 (m) Takes a (list of) recipient address(es) as (an) argument(s),
4154 or asks on standard input if none were given;
4155 then collects the remaining mail content and sends it out.
4159 (mb) The given message list is to be sent to
4161 when \*(UA is quit; this is the default action unless the
4164 \*(ID This command can only be used in a primary system mailbox (see
4169 Without any arguments the content of the MIME type cache will displayed.
4170 Otherwise each argument defines a complete MIME type specification of
4171 a type that shall be added (prepended) to the cache.
4172 In any event MIME type sources are loaded first as necessary \(en
4173 .Va mimetypes-load-control
4174 can be used to fine-tune which sources are actually loaded.
4175 Refer to the section on
4176 .Sx "The mime.types files"
4177 for more on MIME type specifications and this topic in general.
4178 MIME type unregistration and cache resets can be triggered with
4183 Without arguments the list of all currently defined mailing lists
4184 (and their attributes, if any) is shown; a more verbose listing will be
4185 produced if either of
4190 Otherwise all given arguments (which need not be quoted except for
4191 whitespace) will be added and henceforth be recognized as mailing lists.
4192 Mailing lists may be removed via the command
4195 If the \*(OPal regular expression support is available then mailing
4196 lists may also be specified as (extended) regular expressions (see
4202 Without arguments the list of all currently defined mailing lists which
4203 have a subscription attribute is shown; a more verbose listing will be
4204 produced if either of
4209 Otherwise this attribute will be set for all given mailing lists,
4210 newly creating them as necessary (as via
4212 Subscription attributes may be removed via the command
4221 but moves the messages to a file named after the local part of the
4222 sender address of the first message (instead of in
4229 but marks the messages for deletion if they were transferred
4236 but also displays ignored header fields and all MIME parts.
4244 on the given messages, even in non-interactive mode and as long as the
4245 standard output is a terminal.
4251 \*(OP When used without arguments or if
4253 has been given the content of the
4255 cache is shown, loading it first as necessary.
4258 then the cache will only be initialized and
4260 will remove its contents.
4261 Note that \*(UA will try to load the file only once, use
4262 .Ql Ic \&\&netrc Ns \:\0\:clear
4263 to unlock further attempts.
4268 .Sx "On URL syntax and credential lookup" ;
4270 .Sx "The .netrc file"
4271 documents the file format in detail.
4275 Checks for new mail in the current folder without committing any changes
4277 If new mail is present, a message is shown.
4281 the headers of each new message are also shown.
4282 This command is not available for all mailbox types.
4290 Goes to the next message in sequence and types it.
4291 With an argument list, types the next matching message.
4305 If the current folder is accessed via a network connection, a
4307 command is sent, otherwise no operation is performed.
4313 but also displays ignored header fields and all MIME parts.
4321 on the given messages, even in non-interactive mode and as long as the
4322 standard output is a terminal.
4330 but also pipes ignored header fields and all parts of MIME
4331 .Ql multipart/alternative
4336 (pi) Takes a message list and a shell command
4337 and pipes the messages through the command.
4338 Without an argument the current message is piped through the command
4345 every message is followed by a formfeed character.
4366 (q) Terminates the session, saving all undeleted, unsaved messages in
4369 preserving all messages marked with
4373 or never referenced in the system
4375 box, and removing all other messages from the primary system mailbox.
4376 If new mail has arrived during the session,
4378 .Dq You have new mail
4380 If given while editing a mailbox file with the command line flag
4382 then the edit file is rewritten.
4383 A return to the shell is effected,
4384 unless the rewrite of edit file fails,
4385 in which case the user can escape with the exit command.
4399 Removes the named files or directories.
4400 If a name refer to a mailbox, e.g., a Maildir mailbox, then a mailbox
4401 type specific removal will be performed, deleting the complete mailbox.
4402 The user is asked for confirmation in interactive mode.
4406 Takes the name of an existing folder
4407 and the name for the new folder
4408 and renames the first to the second one.
4409 Both folders must be of the same type.
4413 (R) Reply to originator.
4414 Does not reply to other recipients of the original message.
4416 will exchange this command with
4420 is set the recipient address will be stripped from comments, names etc.
4424 (r) Take a message and group-responds to it by addressing the sender
4427 .Va followup-to-honour ,
4430 .Va recipients-in-cc
4431 influence response behaviour.
4434 offers special support for replying to mailing lists.
4437 is set recipient addresses will be stripped from comments, names etc.
4450 but initiates a group-reply regardless of the value of
4457 but responds to the sender only regardless of the value of
4464 but does not add any header lines.
4465 This is not a way to hide the sender's identity,
4466 but useful for sending a message again to the same recipients.
4470 Takes a list of messages and a user name
4471 and sends each message to the named user.
4473 and related header fields are prepended to the new copy of the message.
4491 .It Ic respondsender
4497 (ret) Without arguments the list of retained header fields is shown,
4498 otherwise the given list of header fields is added to the retain list:
4499 Header fields in the retain list are shown on the terminal when
4500 a message is displayed, all other header fields are suppressed.
4501 To display a message in its entirety, use the commands
4510 takes precedence over the mentioned.
4516 but saves the messages in a file named after the local part of the
4517 sender of the first message instead of (in
4519 and) taking a filename argument.
4523 (s) Takes a message list and a filename and appends each message in turn
4524 to the end of the file.
4525 If no filename is given, the
4528 The filename in quotes, followed by the generated character count
4529 is echoed on the user's terminal.
4530 If editing a primary system mailbox the messages are marked for deletion.
4531 Filename interpretation as described for the
4533 command is performed.
4550 Header fields thus marked are filtered out when saving a message by
4552 or when automatically saving to
4554 This command should only be applied to header fields that do not contain
4555 information needed to decode the message,
4556 as MIME content fields do.
4568 Header fields thus marked are the only ones saved with a message when
4571 or when automatically saving to
4576 The use of this command is strongly discouraged since it may strip
4577 header fields that are needed to decode the message correctly.
4581 Takes a message specification (list) and displays a header summary of
4582 all matching messages, as via
4584 This command is an alias of
4587 .Sx "Specifying messages" .
4591 Takes a message list and marks all messages as having been read.
4595 (se) Without arguments this command shows all internal variables which
4596 are currently known to \*(UA (they have been set).
4597 A more verbose listing will be produced if either of
4601 are set, in which case variables may be preceded with a comment line
4602 that gives some context of what \*(UA knows about the given variable.
4604 Otherwise the given variables (and arguments) are set or adjusted.
4605 Arguments are of the form
4607 (no space before or after
4611 if there is no value, i.e., a boolean variable.
4612 Quotation marks may be placed around any part of the assignment
4613 statement to quote blanks or tabs, e.g.,
4615 .Dl set indentprefix='->'
4617 If an argument begins with
4621 the effect is the same as invoking the
4623 command with the remaining part of the variable
4624 .Pf ( Ql unset save ) .
4628 that is known to map to an environment variable will automatically cause
4629 updates in the program environment (unsetting a variable in the
4630 environment requires corresponding system support).
4631 Please use the command
4633 for further environmental control.
4638 .Sx "INTERNAL VARIABLES"
4644 (sh) Invokes an interactive version of the shell.
4648 Without arguments the list of all currently defined shortcuts is
4650 Otherwise all given arguments (which need not be quoted except for
4651 whitespace) are treated as pairs of shortcuts and their expansions,
4652 creating new or changing already existing shortcuts, as necessary.
4653 Shortcuts may be removed via the command
4655 The expansion strings should be in the syntax that has been described
4664 but performs neither MIME decoding nor decryption, so that the raw
4665 message text is shown.
4669 (si) Shows the size in characters of each message of the given
4674 Shows the current sorting criterion when used without an argument.
4675 Otherwise creates a sorted representation of the current folder,
4678 command and the addressing modes such that they refer to messages in
4680 Message numbers are the same as in regular mode.
4684 a header summary in the new order is also displayed.
4685 Automatic folder sorting can be enabled by setting the
4687 variable, as in, e.g.,
4688 .Ql set autosort=thread .
4689 Possible sorting criterions are:
4691 .Bl -tag -compact -offset indent -width "subject"
4693 Sort the messages by their
4695 field, that is by the time they were sent.
4697 Sort messages by the value of their
4699 field, that is by the address of the sender.
4702 variable is set, the sender's real name (if any) is used.
4704 Sort the messages by their size.
4706 \*(OP Sort the message by their spam score, as has been classified by
4709 Sort the messages by their message status.
4711 Sort the messages by their subject.
4713 Create a threaded display.
4715 Sort messages by the value of their
4717 field, that is by the address of the recipient.
4720 variable is set, the recipient's real name (if any) is used.
4725 (so) The source command reads commands from the given file, which is
4726 subject to the usual filename expansions (see introductional words of
4728 If the given argument ends with a vertical bar
4730 then the argument will instead be interpreted as a shell command and
4731 \*(UA will read the output generated by it.
4734 cannot be used from within macros that execute as
4735 .Va folder-hook Ns s
4738 i.e., it can only be called from macros that were
4745 (beside not supporting pipe syntax aka shell command input) is that
4746 this command will not generate an error if the given file argument
4747 cannot be opened successfully.
4748 This can matter in, e.g., resource files, since loading of those is
4749 stopped when an error is encountered.
4753 \*(OP Takes a list of messages and clears their
4759 \*(OP Takes a list of messages and causes the
4761 to forget it has ever used them to train its Bayesian filter.
4762 Unless otherwise noted the
4764 flag of the message is inspected to chose whether a message shall be
4772 \*(OP Takes a list of messages and informs the Bayesian filter of the
4776 This also clears the
4778 flag of the messages in question.
4782 \*(OP Takes a list of messages and rates them using the configured
4783 .Va spam-interface ,
4784 without modifying the messages, but setting their
4786 flag as appropriate; because the spam rating headers are lost the rate
4787 will be forgotten once the mailbox is left.
4788 Refer to the manual section
4790 for the complete picture of spam handling in \*(UA.
4794 \*(OP Takes a list of messages and sets their
4800 \*(OP Takes a list of messages and informs the Bayesian filter of the
4806 flag of the messages in question.
4815 Create a threaded representation of the current folder,
4816 i.\|e. indent messages that are replies to other messages in the header
4817 display and change the
4819 command and the addressing modes such that they refer to messages in the
4821 Message numbers are the same as in unthreaded mode.
4825 a header summary in threaded order is also displayed.
4839 (to) Takes a message list and types out the first
4841 lines of each message on the users' terminal.
4842 The only header fields that are displayed are
4849 will instead honour configured lists).
4850 It is possible to apply compression to what is displayed by setting
4852 Messages are decrypted and converted to the terminal character set
4857 (tou) Takes a message list and marks the messages for saving in
4859 \*(UA deviates from the POSIX standard with this command,
4862 command will display the following message instead of the current one.
4868 but also displays out ignored header fields and all parts of MIME
4869 .Ql multipart/alternative
4874 (t) Takes a message list and types out each message on the users'
4880 For MIME multipart messages, all parts with a content type of
4884 are shown, the other are hidden except for their headers.
4885 Messages are decrypted and converted to the terminal character set
4890 Delete all given accounts.
4891 An error message is shown if a given account is not defined.
4894 will discard all existing accounts.
4898 (una) Takes a list of names defined by alias commands
4899 and discards the remembered groups of users.
4902 will discard all existing aliases.
4906 Takes a message list and marks each message as not having been answered.
4912 ing, specified by its context and input sequence, both of which may be
4913 specified as a wildcard (asterisk,
4917 will remove all bindings of all contexts.
4921 Only applicable to threaded mode.
4922 Takes a message list and makes the message and all replies to it visible
4923 in header summaries again.
4924 When a message becomes the current message,
4925 it is automatically made visible.
4926 Also when a message with collapsed replies is displayed,
4927 all of these are automatically uncollapsed.
4933 mapping for the given colour type (see
4935 for a list of types) and mapping; if the optional precondition argument
4936 is used then only the exact tuple of mapping and precondition is removed.
4939 will remove all mappings (no precondition allowed).
4941 .Sx "Coloured display"
4942 for the general picture.
4946 Deletes the custom headers given as arguments.
4949 will remove all custom headers.
4953 Undefine all given macros.
4954 An error message is shown if a given macro is not defined.
4957 will discard all existing macros.
4961 (u) Takes a message list and marks each message as not being deleted.
4965 Takes a message list and
4971 Takes a message list and marks each message as not being
4976 Removes the header field names from the list of ignored fields for the
4981 will remove all fields.
4985 Removes the header field names from the list of retained fields for the
4990 will remove all fields.
4994 Remove all the given command
4998 will remove all ghosts.
5002 Removes the header field names from the list of ignored fields.
5005 will remove all fields.
5009 Delete all given MIME types, e.g.,
5010 .Ql unmimetype text/plain
5011 will remove all registered specifications for the MIME type
5015 will discard all existing MIME types, just as will
5017 but which also reenables cache initialization via
5018 .Va mimetypes-load-control .
5022 Forget about all the given mailing lists.
5025 will remove all lists.
5030 .It Ic unmlsubscribe
5031 Remove the subscription attribute from all given mailing lists.
5034 will clear the attribute from all lists which have it set.
5045 Takes a message list and marks each message as not having been read.
5049 Removes the header field names from the list of retained fields.
5052 will remove all fields.
5056 Removes the header field names from the list of ignored fields for
5060 will remove all fields.
5064 Removes the header field names from the list of retained fields for
5068 will remove all fields.
5072 (uns) Takes a list of internal variable names and discards their
5073 remembered values; the reverse of
5080 Deletes the shortcut names given as arguments.
5083 will remove all shortcuts.
5087 Disable sorted or threaded mode
5093 return to normal message order and,
5097 displays a header summary.
5107 Decode the given URL-encoded string arguments and show the results.
5108 Note the resulting strings may not be valid in the current locale, see
5113 URL-encode the given arguments and show the results.
5114 Because the arguments effectively are in the character set of the
5115 current locale the results will vary accordingly unless the input solely
5116 consists of characters in the portable character set, see
5117 .Sx "Character sets" .
5121 Edit the values of or create the given variable(s) in the
5123 Boolean variables cannot be edited.
5127 This command produces the same output as the listing mode of
5131 ity adjustments, but only for the given variables.
5135 \*(OP Takes a message list and verifies each message.
5136 If a message is not a S/MIME signed message,
5137 verification will fail for it.
5138 The verification process checks if the message was signed using a valid
5140 if the message sender's email address matches one of those contained
5141 within the certificate,
5142 and if the message content has been altered.
5146 Shows the version and feature set of \*(UA.
5150 (v) Takes a message list and invokes the display editor on each message.
5151 Modified contents are discarded unless the
5157 (w) For conventional messages the body without all headers is written.
5158 The output is decrypted and converted to its native format as necessary.
5159 If the output file exists, the text is appended.
5160 If a message is in MIME multipart format its first part is written to
5161 the specified file as for conventional messages,
5162 and the user is asked for a filename to save each other part.
5163 For convience saving of each part may be skipped by giving an empty value;
5164 the same result can also be achieved by writing it to
5166 For the second and subsequent parts a leading
5168 character causes the part to be piped to the remainder of the user input
5169 interpreted as a shell command;
5170 otherwise the user input is expanded as usually for folders,
5171 e.g., tilde expansion is performed.
5172 In non-interactive mode, only the parts of the multipart message
5173 that have a filename given in the part header are written,
5174 the others are discarded.
5175 The original message is never marked for deletion in the originating
5178 the contents of the destination file are overwritten if the file
5180 No special handling of compressed files is performed.
5189 \*(UA presents message headers in windowfuls as described under the
5192 This command scrolls to the next window of messages.
5193 If an argument is given, it specifies the window to use.
5194 A number prefixed by
5198 indicates that the window is calculated in relation to the current position.
5199 A number without a prefix specifies an absolute window number,
5202 lets \*(UA scroll to the last window of messages.
5208 but scrolls to the next or previous window that contains at least one
5217 .\" .Sh TILDE ESCAPES {{{
5220 Here is a summary of the tilde escapes,
5221 which are used to perform special functions when composing messages.
5222 Tilde escapes are only recognized at the beginning of lines.
5225 is somewhat of a misnomer since the actual escape character can be
5226 changed by adjusting the option
5229 .Bl -tag -width ".Ic __ filename"
5232 Insert the string of text in the message prefaced by a single
5234 (If the escape character has been changed,
5235 that character must be doubled
5236 in order to send it at the beginning of a line.)
5239 .It Ic ~! Ar command
5240 Execute the indicated shell
5242 then return to the message.
5246 Same effect as typing the end-of-file character.
5249 .It Ic ~: Ar \*(UA-command Ns \0or Ic ~_ Ar \*(UA-command
5250 Execute the given \*(UA command.
5251 Not all commands, however, are allowed.
5255 Write a summary of command escapes.
5258 .It Ic ~< Ar filename
5263 .It Ic ~<! Ar command
5265 is executed using the shell.
5266 Its standard output is inserted into the message.
5269 .It Ic ~@ Op Ar filename...
5270 With no arguments, edit the attachment list interactively.
5271 If an attachment's file name is left empty,
5272 that attachment is deleted from the list.
5273 When the end of the attachment list is reached,
5274 \*(UA will ask for further attachments until an empty name is given.
5275 If a given file name solely consists of the number sign
5277 followed by a valid message number of the currently active mailbox, then
5278 the given message is attached as a MIME
5280 and the rest of this section does not apply.
5282 If character set conversion has been compiled into \*(UA, then this mode
5283 gives the user the option to specify input and output character sets,
5284 unless the file extension indicates binary content, in which case \*(UA
5285 asks whether this step shall be skipped for the attachment in question.
5286 If not skipped, then the charset that succeeds to represent the
5287 attachment data will be used in the
5289 MIME parameter of the mail message:
5291 .Bl -bullet -compact
5293 If input and output character sets are specified, then the conversion is
5294 performed on the fly.
5295 The user will be asked repeatedly until the desired conversion succeeds.
5297 If only an output character set is specified, then the input is assumed
5300 charset and will be converted to the given output charset on the fly.
5301 The user will be asked repeatedly until the desired conversion succeeds.
5303 If no character sets are specified at all then the algorithm that is
5304 documented in the section
5305 .Sx "Character sets"
5306 is applied, but directly and on the fly.
5307 The user will be asked repeatedly until the desired conversion succeeds.
5309 Finally, if an input-, but no output character set is specified, then no
5310 conversion is ever performed, but the
5312 MIME parameter value will still be set to the user input.
5314 The character set selection loop can be left by typing
5316 i.e., causing an interrupt.
5317 .\" \*(OU next sentence
5318 Note that before \*(UA version 15.0 this terminates the entire
5319 current attachment selection, not only the character set selection.
5322 Without character set conversion support, \*(UA will ask for the input
5323 character set only, and it'll set the
5325 MIME parameter value to the given input, if any;
5326 if no user input is seen then the
5328 character set will be used for the parameter value instead.
5329 Note that the file extension check isn't performed in this mode, since
5330 no conversion will take place anyway.
5332 Note that in non-interactive mode, for reproduceabilities sake, there
5333 will always be two questions for each attachment, regardless of whether
5334 character set conversion is available and what the file extension is.
5335 The first asks for the filename, and the second asks for the input
5336 character set to be passed through to the corresponding MIME parameter;
5337 no conversion will be tried if there is input to the latter question,
5338 otherwise the usual conversion algorithm, as above, is applied.
5339 For message attachments, the answer to the second question is completely
5344 arguments are specified for the
5346 command they are treated as a file list of
5348 -style quoted arguments, optionally also separated by commas, which are
5349 expanded and then appended to the existing list of message attachments.
5350 Message attachments can only be added via the first method.
5351 In this mode the (text) attachments are assumed to be in
5353 encoding, and will be evaluated as documented in the section
5354 .Sx "Character sets" .
5358 Inserts the string contained in the
5361 .Ql Ic ~i Ns \0Sign ) .
5362 The escape sequences tabulator
5370 Inserts the string contained in the
5373 .Ql Ic ~i Ns \0sign ) .
5374 The escape sequences tabulator
5381 .It Ic ~b Ar name ...
5382 Add the given names to the list of blind carbon copy recipients.
5385 .It Ic ~c Ar name ...
5386 Add the given names to the list of carbon copy recipients.
5390 Read the file specified by the
5392 variable into the message.
5396 Invoke the text editor on the message collected so far.
5397 After the editing session is finished,
5398 the user may continue appending text to the message.
5401 .It Ic ~F Ar messages
5402 Read the named messages into the message being sent, including all
5403 message headers and MIME parts.
5404 If no messages are specified, read in the current message.
5407 .It Ic ~f Ar messages
5408 Read the named messages into the message being sent.
5409 If no messages are specified, read in the current message.
5413 lists are used to modify the message headers.
5414 For MIME multipart messages,
5415 only the first displayable part is included.
5419 Edit the message header fields
5424 by typing each one in turn and allowing the user to edit the field.
5425 The default values for these fields originate from the
5433 Edit the message header fields
5439 by typing each one in turn and allowing the user to edit the field.
5442 .It Ic ~i Ar variable
5443 Insert the value of the specified variable into the message,
5444 adding a newline character at the end.
5445 The message remains unaltered if the variable is unset or empty.
5446 The escape sequences tabulator
5453 .It Ic ~M Ar messages
5454 Read the named messages into the message being sent,
5457 If no messages are specified, read the current message.
5460 .It Ic ~m Ar messages
5461 Read the named messages into the message being sent,
5464 If no messages are specified, read the current message.
5468 lists are used to modify the message headers.
5469 For MIME multipart messages,
5470 only the first displayable part is included.
5474 Display the message collected so far,
5475 prefaced by the message header fields
5476 and followed by the attachment list, if any.
5480 Abort the message being sent,
5481 copying it to the file specified by the
5488 .It Ic ~R Ar filename
5489 Read the named file into the message, indented by
5493 .It Ic ~r Ar filename
5494 Read the named file into the message.
5498 Cause the named string to become the current subject field.
5501 .It Ic ~t Ar name ...
5502 Add the given name(s) to the direct recipient list.
5505 .It Ic ~U Ar messages
5506 Read in the given / current message(s) excluding all headers, indented by
5510 .It Ic ~u Ar messages
5511 Read in the given / current message(s), excluding all headers.
5515 Invoke an alternate editor (defined by the
5517 option) on the message collected so far.
5518 Usually, the alternate editor will be a screen editor.
5519 After the editor is quit,
5520 the user may resume appending text to the end of the message.
5523 .It Ic ~w Ar filename
5524 Write the message onto the named file.
5526 the message is appended to it.
5532 except that the message is not saved at all.
5535 .It Ic ~| Ar command
5536 Pipe the message through the specified filter command.
5537 If the command gives no output or terminates abnormally,
5538 retain the original text of the message.
5541 is often used as a rejustifying filter.
5546 .\" .Sh INTERNAL VARIABLES {{{
5547 .Sh "INTERNAL VARIABLES"
5549 Internal \*(UA variables are controlled via the
5553 commands; prefixing a variable name with the string
5557 has the same effect as using
5563 Creation or editing of variables can be performed in the
5568 will give more insight on the given variable(s), and
5570 when called without arguments, will show a listing of all variables.
5571 Some well-known variables will also become inherited from the
5574 implicitly, others can be explicitly imported with the command
5576 and henceforth share the said properties.
5579 Two different kind of internal variables exist.
5580 There are boolean variables, which can only be in one of the two states
5584 and value variables with a(n optional) string value.
5585 For the latter proper quoting is necessary upon assignment time, the
5586 introduction of the section
5588 documents the supported quoting rules.
5590 .Bd -literal -offset indent
5591 wysh set one=val\e 1 two="val 2" \e
5592 three='val "3"' four=$'val \e'4\e''
5593 varshow one two three four
5594 unset one two three four
5598 Dependent upon the actual option the string values will be interpreted
5599 as numbers, colour names, normal text etc., but there also exists
5600 a special kind of string value, the
5601 .Dq boolean string ,
5602 which must either be a decimal integer (in which case
5606 and any other value is true) or any of the (case-insensitive) strings
5612 for a false boolean and
5618 for a true boolean; a special kind of boolean string is the
5620 which is a boolean string that can optionally be prefixed with the
5621 (case-insensitive) term
5625 which causes prompting of the user in interactive mode, with the given
5626 boolean as the default value.
5628 .\" .Ss "Initial settings" {{{
5629 .\" (Keep in SYNC: ./nail.h:okeys, ./nail.rc, ./nail.1:"Initial settings")
5630 .Ss "Initial Settings"
5632 The standard POSIX 2008/Cor 1-2013 mandates the following initial
5638 .Pf no Va autoprint ,
5652 .Pf no Va ignoreeof ,
5654 .Pf no Va keepsave ,
5656 .Pf no Va outfolder ,
5661 (note that \*(UA deviates from the standard by using
5665 special prompt escape results in
5673 .Pf no Va sendwait ,
5682 Notes: \*(UA doesn't support the
5684 variable \(en use command line options or
5686 to pass options through to a
5688 And the default global
5690 file (which is loaded unless the
5692 command line flag has been used or the
5693 .Ev NAIL_NO_SYSTEM_RC
5694 environment variable is set) bends those initial settings a bit, e.g.,
5695 it sets the variables
5700 to name a few, calls
5702 etc., and should thus be taken into account.
5705 .\" .Ss "Variables" {{{
5708 .Bl -tag -width ".It Va _utoprin_"
5710 .It Va add-file-recipients
5711 \*(BO When file or pipe recipients have been specified,
5712 mention them in the corresponding address fields of the message instead
5713 of silently stripping them from their recipient list.
5714 By default such addressees are not mentioned.
5718 \*(BO Causes only the local part to be evaluated
5719 when comparing addresses.
5723 \*(BO Causes messages saved in
5725 to be appended to the end rather than prepended.
5726 This should always be set.
5730 \*(BO Causes \*(UA to prompt for the subject of each message sent.
5731 If the user responds with simply a newline,
5732 no subject field will be sent.
5736 \*(BO Causes the prompts for
5740 lists to appear after the message has been edited.
5744 \*(BO If set, \*(UA asks for files to attach at the end of each message,
5745 shall the list be found empty at that time.
5746 An empty line finalizes the list.
5750 \*(BO Causes the user to be prompted for carbon copy recipients
5751 (at the end of each message if
5755 are set) shall the list be found empty (at that time).
5756 An empty line finalizes the list.
5760 \*(BO Causes the user to be prompted for blind carbon copy
5761 recipients (at the end of each message if
5765 are set) shall the list be found empty (at that time).
5766 An empty line finalizes the list.
5770 \*(BO\*(OP Causes the user to be prompted if the message is to be
5771 signed at the end of each message.
5774 variable is ignored when this variable is set.
5778 \*(BO Alternative name for
5785 .It Va attachment-ask-content-description , \
5786 attachment-ask-content-disposition , \
5787 attachment-ask-content-id , \
5788 attachment-ask-content-type
5789 \*(BO If set then the user will be prompted for some attachment
5790 information when editing the attachment list.
5791 It is advisable to not use these but for the first of the variables;
5792 even for that it has to be noted that the data is used
5798 A sequence of characters to display in the
5802 as shown in the display of
5804 each for one type of messages (see
5805 .Sx "Message states" ) ,
5806 with the default being
5809 .Ql NU\ \ *HMFAT+\-$~
5812 variable is set, in the following order:
5814 .Bl -tag -compact -offset indent -width ".It Ql _"
5836 start of a collapsed thread.
5838 an uncollapsed thread (TODO ignored for now).
5842 classified as possible spam.
5848 Specifies a list of recipients to which a blind carbon copy of each
5849 outgoing message will be sent automatically.
5853 Specifies a list of recipients to which a carbon copy of each outgoing
5854 message will be sent automatically.
5858 \*(BO Causes threads to be collapsed automatically when threaded mode
5865 \*(BO Causes the delete command to behave like
5867 thus, after deleting a message the next one will be typed automatically.
5871 \*(BO\*(OB Causes threaded mode (see the
5873 command) to be entered automatically when a folder is opened.
5875 .Ql autosort=thread .
5879 Causes sorted mode (see the
5881 command) to be entered automatically with the value of this option as
5882 sorting method when a folder is opened, e.g.,
5883 .Ql set autosort=thread .
5887 \*(BO Enables the substitution of
5889 by the contents of the last command line in shell escapes.
5892 .It Va batch-exit-on-error
5893 \*(BO If the batch mode has been enabled via the
5895 command line option, then this variable will be consulted whenever \*(UA
5896 completes one operation (returns to the command prompt); if it is set
5897 then \*(UA will terminate if the last operation generated an error.
5901 \*(OP Terminals generate multi-byte sequences for certain forms of
5902 input, for example for function and other special keys.
5903 Some terminals however do not write these multi-byte sequences as
5904 a whole, but byte-by-byte, and the latter is what \*(UA actually reads.
5905 This variable specifies the timeout in milliseconds that the MLE (see
5906 .Sx "On terminal control and line editor" )
5907 waits for more bytes to arrive unless it considers a sequence
5913 \*(BO Causes automatic display of a header summary after executing a
5915 command, and thus complements the standard variable
5917 which controls header summary display on program startup.
5918 It is only meaningful if
5924 \*(BO Sets some cosmetical features to traditional BSD style;
5925 has the same affect as setting
5927 and all other variables prefixed with
5929 it also changes the meaning of the \*(UA specific
5932 escape sequence and changes behaviour of
5934 (which doesn't exist in BSD).
5938 \*(BO Changes the letters shown in the first column of a header
5939 summary to traditional BSD style.
5943 \*(BO Changes the display of columns in a header summary to traditional
5948 \*(BO Changes some informational messages to traditional BSD style.
5954 field to appear immediately after the
5956 field in message headers and with the
5958 .Sx "TILDE ESCAPES" .
5962 The value that should appear in the
5966 MIME header fields when no character set conversion of the message data
5968 This defaults to US-ASCII, and the chosen character set should be
5969 US-ASCII compatible.
5973 \*(OP The default 8-bit character set that is used as an implicit last
5974 member of the variable
5976 This defaults to UTF-8.
5977 If no character set conversion capabilities are available in \*(UA then
5978 the only supported character set is
5980 Refer to the section
5981 .Sx "Character sets"
5982 for the complete picture of character set conversion in \*(UA.
5985 .It Va charset-unknown-8bit
5986 \*(OP RFC 1428 specifies conditions when internet mail gateways shall
5988 the content of a mail message by using a character set with the name
5990 Because of the unclassified nature of this character set \*(UA will not
5991 be capable to convert this character set to any other character set.
5992 If this variable is set any message part which uses the character set
5994 is assumed to really be in the character set given in the value,
5995 otherwise the (final) value of
5997 is used for this purpose.
5999 This variable will also be taken into account if a MIME type (see
6000 .Sx "The mime.types files" )
6001 of a MIME message part that uses the
6003 character set is forcefully treated as text.
6007 The default value for the
6012 .It Va colour-disable
6013 \*(BO\*(OP Forcefully disable usage of colours.
6014 Also see the section
6015 .Sx "Coloured display" .
6019 \*(BO\*(OP Whether colour shall be used for output that is paged through
6021 Note that pagers may need special flags, e.g.,
6029 in order to support colours.
6030 Often doing manual adjustments is unnecessary since \*(UA may perform
6031 adjustments dependend on the value of the environment variable
6033 (see there for more).
6037 In a(n interactive) terminal session, then if this valued option is set
6038 it'll be used as a threshold to determine how many lines the given
6039 output has to span before it will be displayed via the configured
6043 can be forced by setting this to the value
6045 setting it without a value will deduce the current height of the
6046 terminal screen to compute the treshold (see
6054 \*(OB A variable counterpart of the
6056 command (see there for documentation), interpreted as a comma-separated
6057 list of custom headers to be injected, to include commas in the header
6058 bodies escape them with reverse solidus, e.g.:
6060 .Dl set customhdr='Hdr1: Body1-1\e, Body1-2, Hdr2: Body2'
6066 the message date, if any is to be displayed according to the format of
6068 is by default taken from the
6070 line of the message.
6071 If this variable is set the date as given in the
6073 header field is used instead, converted to local time.
6074 To control the display format of the date assign a valid
6079 format should not be used, because \*(UA doesn't take embedded newlines
6080 into account when calculating how many lines fit onto the screen.)
6082 .Va datefield-markout-older .
6085 .It Va datefield-markout-older
6086 This option, when set in addition to
6090 messages (concept is rather comparable to the
6092 option of the POSIX utility
6094 The content interpretation is identical to
6099 \*(BO Enables debug messages and obsoletion warnings, disables the
6100 actual delivery of messages and also implies
6106 .It Va disposition-notification-send
6108 .Ql Disposition-Notification-To:
6109 header (RFC 3798) with the message.
6113 .\" TODO .It Va disposition-notification-send-HOST
6115 .\".Va disposition-notification-send
6116 .\" for SMTP accounts on a specific host.
6117 .\" TODO .It Va disposition-notification-send-USER@HOST
6119 .\".Va disposition-notification-send
6120 .\"for a specific account.
6124 \*(BO When dot is set, a period
6126 on a line by itself during message input in (interactive) compose mode
6127 will be treated as end-of-message (in addition to the normal end-of-file
6136 .It Va dotlock-ignore-error
6137 \*(BO\*(OP Synchronization of mailboxes which \*(UA treats as system
6138 mailboxes (see the command
6140 will be protected with so-called dotlock files\(emthe traditional mail
6141 spool file locking method\(emin addition to system file locking.
6142 Because \*(UA ships with a privilege-separated dotlock creation program
6143 that should always be able to create such a dotlock file there is no
6144 good reason to ignore dotlock file creation errors, and thus these are
6145 fatal unless this variable is set.
6149 \*(BO If this variable is set then the editor is started automatically
6150 when a message is composed in interactive mode, as if the
6156 variable is implied for this automatically spawned editor session.
6160 \*(BO When a message is edited while being composed,
6161 its header is included in the editable text.
6171 fields are accepted within the header, other fields are ignored.
6175 \*(BO When entering interactive mode \*(UA normally writes
6176 .Dq \&No mail for user
6177 and exits immediately if a mailbox is empty or doesn't exist.
6178 If this option is set \*(UA starts even with an empty or nonexistent
6179 mailbox (the latter behaviour furtherly depends upon
6185 Suggestion for the MIME encoding to use in outgoing text messages
6187 Valid values are the default
6188 .Ql quoted-printable ,
6193 may cause problems when transferring mail messages over channels that
6194 are not ESMTP (RFC 1869) compliant.
6195 If there is no need to encode a message,
6197 transfer mode is always used regardless of this variable.
6198 Binary data is always encoded as
6203 If defined, the first character of this option
6204 gives the character to use in place of
6207 .Sx "TILDE ESCAPES" .
6211 If not set then file and command pipeline targets are not allowed,
6212 and any such address will be filtered out, giving a warning message.
6213 If set without a value then all possible recipient address
6214 specifications will be accepted \(en see the section
6215 .Sx "On sending mail, and non-interactive mode"
6217 To accept them, but only in interactive mode, or when tilde commands
6218 were enabled explicitly by using one of the command line options
6222 set this to the (case-insensitive) value
6224 (note right now this is actually like setting
6225 .Ql restrict,-all,+name,+addr ) .
6227 In fact the value is interpreted as a comma-separated list of values.
6230 then the existence of disallowed specifications is treated as a hard
6231 send error instead of only filtering them out.
6232 The remaining values specify whether a specific type of recipient
6233 address specification is allowed (optionally indicated by a plus sign
6235 prefix) or disallowed (prefixed with a hyphen
6239 addresses all possible address specifications,
6243 command pipeline targets,
6245 plain user names and (MTA) aliases (\*(OB
6247 may be used as an alternative syntax to
6252 These kind of values are interpreted in the given order, so that
6253 .Ql restrict,\:fail,\:+file,\:-all,\:+addr
6254 will cause hard errors for any non-network address recipient address
6255 unless \*(UA is in interactive mode or has been started with the
6259 command line option; in the latter case(s) any address may be used, then.
6263 Unless this variable is set additional
6265 (Mail-Transfer-Agent)
6266 arguments from the command line, as can be given after a
6268 separator, are ignored due to safety reasons.
6269 However, if set to the special (case-insensitive) value
6271 then the presence of additional MTA arguments is treated as a hard
6272 error that causes \*(UA to exit with failure status.
6273 A lesser strict variant is the otherwise identical
6275 which does accept such arguments in interactive mode, or if tilde
6276 commands were enabled explicitly by using one of the command line options
6283 \*(RO String giving a list of features \*(UA, preceded with a plus-sign
6285 if the feature is available, and a minus-sign
6288 The output of the command
6290 will include this information.
6294 \*(BO This option reverses the meanings of a set of reply commands,
6295 turning the lowercase variants, which by default address all recipients
6296 included in the header of a message
6297 .Pf ( Ic reply , respond , followup )
6298 into the uppercase variants, which by default address the sender only
6299 .Pf ( Ic Reply , Respond , Followup )
6302 .Ic replysender , respondsender , followupsender
6304 .Ic replyall , respondall , followupall
6305 are not affected by the current setting of
6310 .It Va file-hook-load-EXTENSION , file-hook-save-EXTENSION
6311 It is possible to install file hooks which will be used by the
6313 command in order to be able to transparently handle (through an
6314 intermediate temporary file) files with specific
6316 s: the variable values can include shell snippets and are expected to
6317 write data to standard output / read data from standard input,
6319 \*(ID The variables may not be changed while there is a mailbox
6321 .Bd -literal -offset indent
6322 set file-hook-load-xy='echo >&2 XY-LOAD; gzip -cd' \e
6323 file-hook-save-xy='echo >&2 XY-SAVE; gzip -c' \e
6324 record=+null-sent.xy
6329 The default path under which mailboxes are to be saved:
6330 file names that begin with the plus-sign
6332 will be expanded by prefixing them with the value of this variable.
6333 The same special syntax conventions as documented for the
6335 command may be used; if the non-empty value doesn't start with a solidus
6339 will be prefixed automatically.
6340 If unset or the empty string any
6342 prefixing file names will remain unexpanded.
6346 This variable can be set to the name of a
6348 macro which will be called whenever a
6351 The macro will also be invoked when new mail arrives,
6352 but message lists for commands executed from the macro
6353 only include newly arrived messages then.
6355 are activated by default in a folder hook, causing the covered settings
6356 to be reverted once the folder is left again.
6359 Macro behaviour, including option localization, will change in v15.
6360 Please be aware of that and possibly embed a version check in a resource
6364 .It Va folder-hook-FOLDER
6369 Unlike other folder specifications, the fully expanded name of a folder,
6370 without metacharacters, is used to avoid ambiguities.
6371 However, if the mailbox resides under
6375 specification is tried in addition, e.g., if
6379 (and thus relative to the user's home directory) then
6380 .Pa /home/usr1/mail/sent
6382 .Ql folder-hook-/home/usr1/mail/sent
6383 first, but then followed by
6384 .Ql folder-hook-+sent .
6388 \*(BO Controls whether a
6389 .Ql Mail-Followup-To:
6390 header is generated when sending messages to known mailing lists.
6392 .Va followup-to-honour
6394 .Ic mlist , mlsubscribe , reply
6399 .It Va followup-to-honour
6401 .Ql Mail-Followup-To:
6402 header is honoured when group-replying to a message via
6406 This is a quadoption; if set without a value it defaults to
6416 .It Va forward-as-attachment
6417 \*(BO Original messages are normally sent as inline text with the
6420 and only the first part of a multipart message is included.
6421 With this option messages are sent as unmodified MIME
6423 attachments with all of their parts included.
6427 The address (or a list of addresses) to put into the
6429 field of the message header, quoting RFC 5322:
6430 the author(s) of the message, that is, the mailbox(es) of the person(s)
6431 or system(s) responsible for the writing of the message.
6434 ing to messages these addresses are handled as if they were in the
6438 If the machine's hostname is not valid at the Internet (for example at
6439 a dialup machine) then either this variable or
6441 (\*(IN and with a defined SMTP protocol in
6444 adds even more fine-tuning capabilities),
6448 contains more than one address,
6451 variable is required (according to the standard RFC 5322).
6455 \*(BO When replying to or forwarding a message \*(UA normally removes
6456 the comment and name parts of email addresses.
6457 If this variable is set such stripping is not performed,
6458 and comments, names etc. are retained.
6462 The string to put before the text of a message with the
6466 .Va forward-as-attachment
6469 .Dq -------- Original Message --------
6470 if unset; No heading is put if it is set to the empty string.
6474 \*(BO Causes the header summary to be written at startup and after
6475 commands that affect the number of messages or the order of messages in
6476 the current folder; enabled by default.
6477 The command line option
6483 complements this and controls header summary display on folder changes.
6488 A format string to use for the summary of
6490 similar to the ones used for
6493 Format specifiers in the given string start with a percent character
6495 and may be followed by an optional decimal number indicating the field
6496 width \(em if that is negative, the field is to be left-aligned.
6497 Valid format specifiers are:
6500 .Bl -tag -compact -offset indent -width "_%%_"
6502 A plain percent character.
6505 a space character but for the current message
6507 for which it expands to
6511 a space character but for the current message
6513 for which it expands to
6516 \*(OP The spam score of the message, as has been classified via the
6519 Shows only a replacement character if there is no spam support.
6521 Message attribute character (status flag); the actual content can be
6525 The date when the message was received, or the date found in the
6529 variable is set (optionally to a date display format string).
6531 The indenting level in threaded mode.
6533 The address of the message sender.
6535 The message thread tree structure.
6536 (Note that this format doesn't support a field width.)
6538 The number of lines of the message, if available.
6542 The number of octets (bytes) in the message, if available.
6544 Message subject (if any).
6546 Message subject (if any) in double quotes.
6548 Message recipient flags: is the addressee of the message a known or
6549 subscribed mailing list \(en see
6554 The position in threaded/sorted order.
6558 .Ql %>\&%a\&%m\ %-18f\ %16d\ %4l/%\-5o\ %i%-s ,
6560 .Ql %>\&%a\&%m\ %20-f\ \ %16d\ %3l/%\-5o\ %i%-S
6571 .It Va headline-bidi
6572 Bidirectional text requires special treatment when displaying headers,
6573 because numbers (in dates or for file sizes etc.) will not affect the
6574 current text direction, in effect resulting in ugly line layouts when
6575 arabic or other right-to-left text is to be displayed.
6576 On the other hand only a minority of terminals is capable to correctly
6577 handle direction changes, so that user interaction is necessary for
6579 Note that extended host system support is required nonetheless, e.g.,
6580 detection of the terminal character set is one precondition;
6581 and this feature only works in an Unicode (i.e., UTF-8) locale.
6583 In general setting this variable will cause \*(UA to encapsulate text
6584 fields that may occur when displaying
6586 (and some other fields, like dynamic expansions in
6588 with special Unicode control sequences;
6589 it is possible to fine-tune the terminal support level by assigning
6591 no value (or any value other than
6596 will make \*(UA assume that the terminal is capable to properly deal
6597 with Unicode version 6.3, in which case text is embedded in a pair of
6598 U+2068 (FIRST STRONG ISOLATE) and U+2069 (POP DIRECTIONAL ISOLATE)
6600 In addition no space on the line is reserved for these characters.
6602 Weaker support is chosen by using the value
6604 (Unicode 6.3, but reserve the room of two spaces for writing the control
6605 sequences onto the line).
6610 select Unicode 1.1 support (U+200E, LEFT-TO-RIGHT MARK); the latter
6611 again reserves room for two spaces in addition.
6615 \*(OP If a line editor is available then this can be set to
6616 name the (expandable) path of the location of a permanent history file.
6619 .It Va history-gabby
6620 \*(BO\*(OP Add more entries to the history as is normally done.
6623 .It Va history-gabby-persist
6624 \*(BO\*(OP \*(UA's own MLE will not save the additional
6626 entries in persistent storage unless this variable is set.
6627 On the other hand it will not loose the knowledge of whether
6628 a persistent entry was gabby or not.
6634 \*(OP If a line editor is available this value restricts the
6635 amount of history entries that are saved into a set and valid
6637 A value of less than 0 disables this feature;
6638 note that loading and incorporation of
6640 upon program startup can also be suppressed by doing this.
6641 If unset or 0, a default value will be used.
6642 Dependent on the available line editor this will also define the
6643 number of history entries in memory;
6644 it is also editor-specific whether runtime updates of this value will
6649 \*(BO This option is used to hold messages in the system
6651 box, and it is set by default.
6655 Use this string as hostname when expanding local addresses instead of
6656 the value obtained from
6665 Note that when SMTP transport is not used (via
6667 then it is normally the responsibility of the MTA to create these
6668 fields, \*(IN in conjunction with SMTP however
6670 also influences the results:
6671 you should produce some test messages with the desired combination of
6680 \*(BO\*(OP Can be used to turn off the automatic conversion of domain
6681 names according to the rules of IDNA (internationalized domain names
6683 Since the IDNA code assumes that domain names are specified with the
6685 character set, an UTF-8 locale charset is required to represent all
6686 possible international domain names (before conversion, that is).
6690 \*(BO Ignore interrupt signals from the terminal while entering
6691 messages; instead echo them as
6693 characters and discard the current line.
6697 \*(BO Ignore end-of-file conditions
6698 .Pf ( Ql control-D )
6699 in compose mode on message input and in interactive command input.
6700 If set an interactive command input session can only be left by
6701 explicitly using one of the commands
6705 and message input in compose mode can only be terminated by entering
6708 on a line by itself or by using the
6710 .Sx "TILDE ESCAPES" ;
6712 overrides a setting of
6724 option for indenting messages,
6725 in place of the normal tabulator character
6727 which is the default.
6728 Be sure to quote the value if it contains spaces or tabs.
6732 \*(BO If set, an empty mailbox file is not removed.
6733 This may improve the interoperability with other mail user agents
6734 when using a common folder directory, and prevents malicious users
6735 from creating fake mailboxes in a world-writable spool directory.
6736 Note this only applies to local regular (MBOX) files, other mailbox
6737 types will never be removed.
6740 .It Va keep-content-length
6741 \*(BO When (editing messages and) writing
6743 mailbox files \*(UA can be told to keep the
6747 header fields that some MUAs generate by setting this variable.
6748 Since \*(UA does neither use nor update these non-standardized header
6749 fields (which in itself shows one of their conceptual problems),
6750 stripping them should increase interoperability in between MUAs that
6751 work with with same mailbox files.
6752 Note that, if this is not set but
6753 .Va writebackedited ,
6754 as below, is, a possibly performed automatic stripping of these header
6755 fields already marks the message as being modified.
6759 \*(BO When a message is saved it is usually discarded from the
6760 originating folder when \*(UA is quit.
6761 Setting this option causes all saved message to be retained.
6764 .It Va line-editor-disable
6765 \*(BO Turn off any enhanced line editing capabilities (see
6766 .Sx "On terminal control and line editor"
6770 .It Va line-editor-no-defaults
6771 \*(BO\*(OP Do not establish any default key binding.
6775 \*(BO When a message is replied to and this variable is set,
6776 it is marked as having been answered.
6777 This mark has no technical meaning in the mail system;
6778 it just causes messages to be marked in the header summary,
6779 and makes them specially addressable.
6783 \*(BO \*(UA generates and expects RFC 4155 compliant MBOX text
6785 (With the restriction that RFC 4155 defines seven-bit clean data
6786 storage, but which can be overwritten by a contrary setting of
6788 Messages which are fetched over the network or from within already
6789 existing Maildir (or any non-MBOX) mailboxes may require so-called
6791 quoting (insertion of additional
6793 characters to prevent line content misinterpretation) to be applied in
6794 order to be storable in MBOX mailboxes, however, dependent on the
6795 circumspection of the message producer.
6796 E.g., \*(UA itself will, when newly generating messages, choose a
6797 .Pf Content-Transfer- Va encoding
6798 that prevents the necessity for such quoting \(en a necessary
6799 precondition to ensure message checksums won't change.
6801 By default \*(UA will perform this
6803 quoting in a way that results in a MBOX file that is compatible with
6804 the POSIX MBOX layout, which means that, in order not to exceed the
6805 capabilities of simple applications, many more
6807 lines get quoted (thus modified) than necessary according to RFC 4155.
6808 Set this option to instead generate MBOX files which comply to RFC 4155.
6812 \*(BO Internal development variable.
6815 .It Va message-id-disable
6816 \*(BO By setting this option the generation of
6818 can be completely suppressed, effectively leaving this task up to the
6820 (Mail-Transfer-Agent) or the SMTP server.
6821 (According to RFC 5321 your SMTP server is not required to add this
6822 field by itself, so you should ensure that it accepts messages without a
6826 .It Va message-inject-head
6827 A string to put at the beginning of each new message.
6828 The escape sequences tabulator
6835 .It Va message-inject-tail
6836 A string to put at the end of each new message.
6837 The escape sequences tabulator
6845 \*(BO Usually, when an
6847 expansion contains the sender, the sender is removed from the expansion.
6848 Setting this option suppresses these removals.
6853 option to be passed through to the
6855 (Mail-Transfer-Agent); though most of the modern MTAs no longer document
6856 this flag, no MTA is known which doesn't support it (for historical
6860 .It Va mime-allow-text-controls
6861 \*(BO When sending messages, each part of the message is MIME-inspected
6862 in order to classify the
6865 .Ql Content-Transfer-Encoding:
6868 that is required to send this part over mail transport, i.e.,
6869 a computation rather similar to what the
6871 command produces when used with the
6875 This classification however treats text files which are encoded in
6876 UTF-16 (seen for HTML files) and similar character sets as binary
6877 octet-streams, forcefully changing any
6882 .Ql application/octet-stream :
6883 If that actually happens a yet unset charset MIME parameter is set to
6885 effectively making it impossible for the receiving MUA to automatically
6886 interpret the contents of the part.
6888 If this option is set, and the data was unambiguously identified as text
6889 data at first glance (by a
6893 file extension), then the original
6895 will not be overwritten.
6898 .It Va mime-alternative-favour-rich
6899 \*(BO If this variable is set then rich MIME alternative parts (e.g.,
6900 HTML) will be preferred in favour of included plain text versions when
6901 displaying messages, provided that a handler exists which produces
6902 output that can be (re)integrated into \*(UA's normal visual display.
6903 (E.g., at the time of this writing some newsletters ship their full
6904 content only in the rich HTML part, whereas the plain text part only
6905 contains topic subjects.)
6908 .It Va mime-counter-evidence
6911 field is used to decide how to handle MIME parts.
6912 Some MUAs however don't use
6914 or a similar mechanism to correctly classify content, but simply specify
6915 .Ql application/octet-stream ,
6916 even for plain text attachments like
6918 If this variable is set then \*(UA will try to classify such MIME
6919 message parts on its own, if possible, for example via a possibly
6920 existent attachment filename.
6921 A non-empty value may also be given, in which case a number is expected,
6922 actually a carrier of bits.
6923 Creating the bit-carrying number is a simple addition:
6924 .Bd -literal -offset indent
6925 ? !echo Value should be set to $((2 + 4 + 8))
6926 Value should be set to 14
6929 .Bl -bullet -compact
6931 If bit two is set (2) then the detected
6933 content-type will be carried along with the message and be used for
6935 .Va pipe-TYPE/SUBTYPE
6936 is responsible for the MIME part, shall that question arise;
6937 when displaying such a MIME part the part-info will indicate the
6938 overridden content-type by showing a plus-sign
6941 If bit three is set (4) then the counter-evidence is always produced
6942 and a positive result will be used as the MIME type, even forcefully
6943 overriding the parts given MIME type.
6945 If bit four is set (8) then as a last resort the actual content of
6946 .Ql application/octet-stream
6947 parts will be inspected, so that data which looks like plain text can be
6952 .It Va mimetypes-load-control
6953 This option can be used to control which of the
6955 databases are loaded by \*(UA, as furtherly described in the section
6956 .Sx "The mime.types files" .
6959 is part of the option value, then the user's personal
6961 file will be loaded (if it exists); likewise the letter
6963 controls loading of the system wide
6964 .Pa /etc/mime.types ;
6965 directives found in the user file take precedence, letter matching is
6967 If this option is not set \*(UA will try to load both files.
6968 Incorporation of the \*(UA-builtin MIME types cannot be suppressed,
6969 but they will be matched last.
6971 More sources can be specified by using a different syntax: if the
6972 value string contains an equals sign
6974 then it is instead parsed as a comma-separated list of the described
6977 pairs; the given filenames will be expanded and loaded, and their
6978 content may use the extended syntax that is described in the section
6979 .Sx "The mime.types files" .
6980 Directives found in such files always take precedence (are prepended to
6981 the MIME type cache).
6986 To choose an alternate Mail-Transfer-Agent, set this option to either
6987 the full pathname of an executable (optionally prefixed with a
6989 protocol indicator), or \*(OPally a SMTP protocol URL, e.g., \*(IN
6991 .Dl smtps?://[user[:password]@]server[:port]
6994 .Ql [smtp://]server[:port] . )
6995 The default has been chosen at compie time.
6996 All supported data transfers are executed in child processes, which
6997 run asynchronously, and without supervision, unless either the
7002 If such a child receives a TERM signal, it will abort and
7009 For a file-based MTA it may be necessary to set
7011 in in order to choose the right target of a modern
7014 It will be passed command line arguments from several possible sources:
7017 if set, from the command line if given and the variable
7020 Argument processing of the MTA will be terminated with a
7025 The otherwise occurring implicit usage of the following MTA command
7026 line arguments can be disabled by setting the boolean option
7027 .Va mta-no-default-arguments
7028 (which will also disable passing
7032 (for not treating a line with only a dot
7034 character as the end of input),
7042 option is set); in conjunction with the
7044 command line option \*(UA will also pass
7050 \*(OP \*(UA can send mail over SMTP network connections to a single
7051 defined SMTP smarthost, the access URL of which has to be assigned to
7053 To use this mode it is helpful to read
7054 .Sx "On URL syntax and credential lookup" .
7055 It may be necessary to set the
7057 variable in order to use a specific combination of
7062 with some mail providers.
7065 .Bl -bullet -compact
7067 The plain SMTP protocol (RFC 5321) that normally lives on the
7068 server port 25 and requires setting the
7069 .Va smtp-use-starttls
7070 variable to enter a SSL/TLS encrypted session state.
7071 Assign a value like \*(IN
7072 .Ql smtp://[user[:password]@]server[:port]
7074 .Ql smtp://server[:port] )
7075 to choose this protocol.
7077 The so-called SMTPS which is supposed to live on server port 465
7078 and is automatically SSL/TLS secured.
7079 Unfortunately it never became a standardized protocol and may thus not
7080 be supported by your hosts network service database
7081 \(en in fact the port number has already been reassigned to other
7084 SMTPS is nonetheless a commonly offered protocol and thus can be
7085 chosen by assigning a value like \*(IN
7086 .Ql smtps://[user[:password]@]server[:port]
7088 .Ql smtps://server[:port] ) ;
7089 due to the mentioned problems it is usually necessary to explicitly
7094 Finally there is the SUBMISSION protocol (RFC 6409), which usually
7095 lives on server port 587 and is practically identically to the SMTP
7096 protocol from \*(UA's point of view beside that; it requires setting the
7097 .Va smtp-use-starttls
7098 variable to enter a SSL/TLS secured session state.
7099 Assign a value like \*(IN
7100 .Ql submission://[user[:password]@]server[:port]
7102 .Ql submission://server[:port] ) .
7107 .It Va mta-arguments
7108 Arguments to pass through to a file-based
7110 can be given via this variable, the content of which will be split up in
7111 a vector of arguments, to be joined onto other possible MTA options:
7113 .Dl set mta-arguments='-t -X \&"/tmp/my log\&"'
7116 .It Va mta-no-default-arguments
7117 \*(BO Unless this option is set \*(UA will pass some well known
7118 standard command line options to a file-based
7120 (Mail-Transfer-Agent), see there for more.
7124 Many systems use a so-called
7126 environment to ensure compatibility with
7128 This works by inspecting the name that was used to invoke the mail
7130 If this variable is set then the mailwrapper (the program that is
7131 actually executed when calling the file-based
7133 will treat its contents as that name.
7138 .It Va NAIL_EXTRA_RC
7139 The name of an optional startup file to be read last.
7140 This variable has an effect only if it is set in any of the
7141 .Sx "Resource files" ,
7142 it is not imported from the environment.
7143 Use this file for commands that are not understood by other POSIX
7148 .It Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup
7149 \*(BO\*(IN\*(OP Used to control usage of the users
7151 file for lookup of account credentials, as documented in the section
7152 .Sx "On URL syntax and credential lookup"
7156 .Sx "The .netrc file"
7157 documents the file format.
7169 then \*(UA will read the output of a shell pipe instead of the users
7171 file if this variable is set (to the desired shell command).
7172 This can be used to, e.g., store
7176 .Dl set netrc-pipe='gpg -qd ~/.netrc.pgp'
7180 If this variable has the value
7182 newly created local folders will be in Maildir format.
7186 Checks for new mail in the current folder each time the prompt is shown.
7187 A Maildir folder must be re-scanned to determine if new mail has arrived.
7188 If this variable is set to the special value
7190 then a Maildir folder will not be rescanned completely, but only
7191 timestamp changes are detected.
7195 .It Va on-compose-enter , on-compose-leave
7196 \*(ID Macro hooks which will be executed before compose mode is
7197 entered, and after composing has been finished, respectively.
7198 Please note that this interface is very likely to change in v15, and
7199 should therefore possibly even be seen as experimental.
7201 are by default enabled for these hooks, causing any setting to be
7202 forgotten after the message has been sent.
7203 The following variables will be set temporarily during execution of the
7206 .Bl -tag -compact -width ".It Va compose_subject"
7209 .It Va compose-sender
7211 .It Va compose-to , compose-cc , compose-bcc
7212 The list of receiver addresses as a space-separated list.
7213 .It Va compose-subject
7219 \*(BO Causes the filename given in the
7222 and the sender-based filenames for the
7226 commands to be interpreted relative to the directory given in the
7228 variable rather than to the current directory,
7229 unless it is set to an absolute pathname.
7233 \*(BO If set, each message feed through the command given for
7235 is followed by a formfeed character
7239 .It Va password-USER@HOST , password-HOST , password
7240 \*(IN Variable chain that sets a password, which is used in case none has
7241 been given in the protocol and account-specific URL;
7242 as a last resort \*(UA will ask for a password on the user's terminal if
7243 the authentication method requires a password.
7244 Specifying passwords in a startup file is generally a security risk;
7245 the file should be readable by the invoking user only.
7247 .It Va password-USER@HOST
7248 \*(OU (see the chain above for \*(IN)
7249 Set the password for
7253 If no such variable is defined for a host,
7254 the user will be asked for a password on standard input.
7255 Specifying passwords in a startup file is generally a security risk;
7256 the file should be readable by the invoking user only.
7260 \*(BO Send messages to the
7262 command without performing MIME and character set conversions.
7266 .It Va pipe-TYPE/SUBTYPE
7267 When a MIME message part of type
7269 (case-insensitive) is displayed or quoted,
7270 its text is filtered through the value of this variable interpreted as
7274 forces interpretation of the message part as plain text, e.g.,
7275 .Ql set pipe-application/xml=@
7276 will henceforth display XML
7278 (The same could also be achieved by adding a MIME type marker with the
7281 And \*(OPally MIME type handlers may be defined via
7282 .Sx "The Mailcap files"
7283 \(em corresponding flag strings are shown in parenthesis below.)
7288 can in fact be used to adjust usage and behaviour of a following shell
7289 command specification by appending trigger characters to it, e.g., the
7290 following hypothetical command specification could be used:
7291 .Bd -literal -offset indent
7292 set pipe-X/Y='@*!++=@vim ${NAIL_FILENAME_TEMPORARY}'
7296 .Bl -tag -compact -width ".It Ql __"
7298 Simply by using the special
7300 prefix the MIME type (shell command) handler will only be invoked to
7301 display or convert the MIME part if the message is addressed directly
7302 and alone by itself.
7303 Use this trigger to disable this and always invoke the handler
7304 .Pf ( Cd x-mailx-always ) .
7307 If set the handler will not be invoked when a message is to be quoted,
7308 but only when it will be displayed
7309 .Pf ( Cd x-mailx-noquote ) .
7312 The command will be run asynchronously, i.e., without blocking \*(UA,
7313 which may be a handy way to display a, e.g., PDF file while also
7314 continuing to read the mail message
7315 .Pf ( Cd x-mailx-async ) .
7316 Asynchronous execution implies
7320 The command must be run on an interactive terminal, \*(UA will
7321 temporarily release the terminal to it
7322 .Pf ( Cd needsterminal ) .
7323 This flag is mutual exclusive with
7325 will only be used in interactive mode and implies
7329 Request creation of a zero-sized temporary file, the absolute pathname
7330 of which will be made accessible via the environment variable
7331 .Ev NAIL_FILENAME_TEMPORARY
7332 .Pf ( Cd x-mailx-tmpfile ) .
7333 If this trigger is given twice then the file will be unlinked
7334 automatically by \*(UA when the command loop is entered again at latest
7335 .Pf ( Cd x-mailx-tmpfile-unlink ) .
7336 (Don't use this for asynchronous handlers.)
7339 Normally the MIME part content is passed to the handler via standard
7340 input; if this flag is set then the data will instead be written into
7341 .Ev NAIL_FILENAME_TEMPORARY
7342 .Pf ( Cd x-mailx-tmpfile-fill ) ,
7343 the creation of which is implied; note however that in order to cause
7344 deletion of the temporary file you still have to use two plus signs
7349 To avoid ambiguities with normal shell command content you can use
7350 another at-sign to forcefully terminate interpretation of remaining
7352 (Any character not in this list will have the same effect.)
7356 Some information about the MIME part to be displayed is embedded into
7357 the environment of the shell command:
7360 .Bl -tag -compact -width ".It Ev _AIL__ILENAME__ENERATED"
7363 The MIME content-type of the part, if known, the empty string otherwise.
7366 .It Ev NAIL_CONTENT_EVIDENCE
7368 .Va mime-counter-evidence
7369 includes the carry-around-bit (2), then this will be set to the detected
7370 MIME content-type; not only then identical to
7371 .Ev \&\&NAIL_CONTENT
7375 .It Ev NAIL_FILENAME
7376 The filename, if any is set, the empty string otherwise.
7379 .It Ev NAIL_FILENAME_GENERATED
7383 .It Ev NAIL_FILENAME_TEMPORARY
7384 If temporary file creation has been requested through the command prefix
7385 this variable will be set and contain the absolute pathname of the
7390 The temporary directory that \*(UA uses.
7391 Usually identical to
7393 but guaranteed to be set and usable by child processes;
7394 to ensure the latter condition for
7401 .It Va pipe-EXTENSION
7402 This is identical to
7403 .Va pipe-TYPE/SUBTYPE
7406 (normalized to lowercase using character mappings of the ASCII charset)
7407 names a file extension, e.g.,
7409 Handlers registered using this method take precedence.
7412 .It Va pop3-auth-USER@HOST , pop3-auth-HOST , pop3-auth
7413 \*(OP\*(IN Variable chain that sets the POP3 authentication method.
7414 The only possible value as of now is
7416 which is thus the default.
7419 .Mx Va pop3-bulk-load
7420 .It Va pop3-bulk-load-USER@HOST , pop3-bulk-load-HOST , pop3-bulk-load
7421 \*(BO\*(OP When accessing a POP3 server \*(UA loads the headers of
7422 the messages, and only requests the message bodies on user request.
7423 For the POP3 protocol this means that the message headers will be
7425 If this option is set then \*(UA will download only complete messages
7426 from the given POP3 server(s) instead.
7428 .Mx Va pop3-keepalive
7429 .It Va pop3-keepalive-USER@HOST , pop3-keepalive-HOST , pop3-keepalive
7430 \*(OP POP3 servers close the connection after a period of inactivity;
7431 the standard requires this to be at least 10 minutes,
7432 but practical experience may vary.
7433 Setting this variable to a numeric value greater than
7437 command to be sent each value seconds if no other operation is performed.
7440 .It Va pop3-no-apop-USER@HOST , pop3-no-apop-HOST , pop3-no-apop
7441 \*(BO\*(OP Unless this variable is set the
7443 authentication method will be used when connecting to a POP3 server that
7447 is that the password is not sent in clear text over the wire and that
7448 only a single packet is sent for the user/password tuple.
7450 .Va pop3-no-apop-HOST
7453 .Mx Va pop3-use-starttls
7454 .It Va pop3-use-starttls-USER@HOST , pop3-use-starttls-HOST , pop3-use-starttls
7455 \*(BO\*(OP Causes \*(UA to issue a
7457 command to make an unencrypted POP3 session SSL/TLS encrypted.
7458 This functionality is not supported by all servers,
7459 and is not used if the session is already encrypted by the POP3S method.
7461 .Va pop3-use-starttls-HOST
7465 .It Va print-alternatives
7466 \*(BO When a MIME message part of type
7467 .Ql multipart/alternative
7468 is displayed and it contains a subpart of type
7470 other parts are normally discarded.
7471 Setting this variable causes all subparts to be displayed,
7472 just as if the surrounding part was of type
7473 .Ql multipart/mixed .
7477 The string shown when a command is accepted.
7478 Prompting may be prevented by setting this to the null string
7480 .Pf no Va prompt ) .
7481 If a value is assigned the following \*(UA specific additional sequences
7488 is set, in which case it expands to
7492 is the default value of
7495 which will expand to
7497 if the last command failed and to
7501 which will expand to the name of the currently active
7503 if any, and to the empty string otherwise, and
7505 which will expand to the name of the currently active mailbox.
7506 (Note that the prompt buffer is size-limited, excess is cut off.)
7512 to encapsulate the expansions of the
7516 escape sequences as necessary to correctly display bidirectional text,
7517 this is not true for the final string that makes up
7519 as such, i.e., real BIDI handling is not supported.
7523 \*(BO Suppresses the printing of the version when first invoked.
7527 If set, \*(UA starts a replying message with the original message
7528 prefixed by the value of the variable
7530 Normally, a heading consisting of
7531 .Dq Fromheaderfield wrote:
7532 is put before the quotation.
7537 variable, this heading is omitted.
7540 is assigned, the headers selected by the
7541 .Ic ignore Ns / Ns Ic retain
7542 commands are put above the message body,
7545 acts like an automatic
7551 is assigned, all headers are put above the message body and all MIME
7552 parts are included, making
7554 act like an automatic
7557 .Va quote-as-attachment .
7560 .It Va quote-as-attachment
7561 \*(BO Add the original message in its entirety as a
7563 MIME attachment when replying to a message.
7564 Note this works regardless of the setting of
7569 \*(OP Can be set in addition to
7571 Setting this turns on a more fancy quotation algorithm in that leading
7572 quotation characters are compressed and overlong lines are folded.
7574 can be set to either one or two (space separated) numeric values,
7575 which are interpreted as the maximum (goal) and the minimum line length,
7576 respectively, in a spirit rather equal to the
7578 program, but line-, not paragraph-based.
7579 If not set explicitly the minimum will reflect the goal algorithmically.
7580 The goal can't be smaller than the length of
7582 plus some additional pad.
7583 Necessary adjustments take place silently.
7586 .It Va recipients-in-cc
7587 \*(BO On group replies, specify only the sender of the original mail in
7589 and mention the other recipients in the secondary
7591 By default all recipients of the original mail will be addressed via
7596 If defined, gives the pathname of the folder used to record all outgoing
7598 If not defined, then outgoing mail is not saved.
7599 When saving to this folder fails the message is not sent,
7600 but instead saved to
7604 .It Va record-resent
7605 \*(BO If both this variable and the
7612 commands save messages to the
7614 folder as it is normally only done for newly composed messages.
7617 .It Va reply-in-same-charset
7618 \*(BO If this variable is set \*(UA first tries to use the same
7619 character set of the original message for replies.
7620 If this fails, the mechanism described in
7621 .Sx "Character sets"
7622 is evaluated as usual.
7625 .It Va reply_strings
7626 Can be set to a comma-separated list of (case-insensitive according to
7627 ASCII rules) strings which shall be recognized in addition to the
7630 reply message indicators \(en builtin are
7632 which is mandated by RFC 5322, as well as the german
7637 A list of addresses to put into the
7639 field of the message header.
7640 Members of this list are handled as if they were in the
7645 .It Va reply-to-honour
7648 header is honoured when replying to a message via
7652 This is a quadoption; if set without a value it defaults to
7656 .It Va rfc822-body-from_
7657 \*(BO This variable can be used to force displaying a so-called
7659 line for messages that are embedded into an envelope mail via the
7661 MIME mechanism, for more visual convenience.
7665 \*(BO Enable saving of (partial) messages in
7667 upon interrupt or delivery error.
7671 The number of lines that represents a
7680 line display and scrolling via
7682 If this variable is not set \*(UA falls back to a calculation based upon
7683 the detected terminal window size and the baud rate: the faster the
7684 terminal, the more will be shown.
7685 Overall screen dimensions and pager usage is influenced by the
7686 environment variables
7694 .It Va searchheaders
7695 \*(BO Expand message-list specifiers in the form
7697 to all messages containing the substring
7701 The string search is case insensitive.
7705 \*(OP A comma-separated list of character set names that can be used in
7706 outgoing internet mail.
7707 The value of the variable
7709 is automatically appended to this list of character-sets.
7710 If no character set conversion capabilities are compiled into \*(UA then
7711 the only supported charset is
7714 .Va sendcharsets-else-ttycharset
7715 and refer to the section
7716 .Sx "Character sets"
7717 for the complete picture of character set conversion in \*(UA.
7720 .It Va sendcharsets-else-ttycharset
7721 \*(BO\*(OP If this variable is set, but
7723 is not, then \*(UA acts as if
7725 had been set to the value of the variable
7727 In effect this combination passes through the message data in the
7728 character set of the current locale (given that
7730 hasn't been set manually), i.e., without converting it to the
7732 fallback character set.
7733 Thus, mail message text will be in ISO-8859-1 encoding when send from
7734 within a ISO-8859-1 locale, and in UTF-8 encoding when send from within
7736 If no character set conversion capabilities are available in \*(UA then
7737 the only supported character set is
7742 An address that is put into the
7744 field of outgoing messages, quoting RFC 5322: the mailbox of the agent
7745 responsible for the actual transmission of the message.
7746 This field should normally not be used unless the
7748 field contains more than one address, on which case it is required.
7751 address is handled as if it were in the
7757 \*(OB Predecessor of
7761 .It Va sendmail-arguments
7762 \*(OB Predecessor of
7766 .It Va sendmail-no-default-arguments
7767 \*(OB\*(BO Predecessor of
7768 .Va mta-no-default-arguments .
7771 .It Va sendmail-progname
7772 \*(OB Predecessor of
7777 \*(BO When sending a message wait until the
7779 (including the builtin SMTP one) exits before accepting further commands.
7781 with this variable set errors reported by the MTA will be recognizable!
7782 If the MTA returns a non-zero exit status,
7783 the exit status of \*(UA will also be non-zero.
7787 \*(BO Setting this option causes \*(UA to start at the last message
7788 instead of the first one when opening a mail folder.
7792 \*(BO Causes \*(UA to use the sender's real name instead of the plain
7793 address in the header field summary and in message specifications.
7797 \*(BO Causes the recipient of the message to be shown in the header
7798 summary if the message was sent by the user.
7802 A string for use with the
7808 A string for use with the
7814 Must correspond to the name of a readable file if set.
7815 The file's content is then appended to each singlepart message
7816 and to the first part of each multipart message.
7817 Be warned that there is no possibility to edit the signature for an
7821 .It Va skipemptybody
7822 \*(BO If an outgoing message does not contain any text in its first or
7823 only message part, do not send it but discard it silently (see also the
7829 \*(OP Specifies a directory with CA certificates in PEM (Privacy
7830 Enhanced Mail) format for verification of S/MIME signed messages.
7833 .It Va smime-ca-file
7834 \*(OP Specifies a file with CA certificates in PEM format for
7835 verification of S/MIME signed messages.
7838 .It Va smime-cipher-USER@HOST , smime-cipher
7839 \*(OP Specifies the cipher to use when generating S/MIME encrypted
7840 messages (for the specified account).
7841 RFC 5751 mandates a default of
7844 Possible values are (case-insensitive and) in decreasing cipher strength:
7852 (DES EDE3 CBC, 168 bits; default if
7854 isn't available) and
7858 The actually available cipher algorithms depend on the cryptographic
7859 library that \*(UA uses.
7860 \*(OP Support for more cipher algorithms may be available through
7861 dynamic loading via, e.g.,
7862 .Xr EVP_get_cipherbyname 3
7863 (OpenSSL) if \*(UA has been compiled to support this.
7866 .It Va smime-crl-dir
7867 \*(OP Specifies a directory that contains files with CRLs in PEM format
7868 to use when verifying S/MIME messages.
7871 .It Va smime-crl-file
7872 \*(OP Specifies a file that contains a CRL in PEM format to use when
7873 verifying S/MIME messages.
7876 .It Va smime-encrypt-USER@HOST
7877 \*(OP If this variable is set, messages send to the given receiver are
7878 encrypted before sending.
7879 The value of the variable must be set to the name of a file that
7880 contains a certificate in PEM format.
7882 If a message is sent to multiple recipients,
7883 each of them for whom a corresponding variable is set will receive an
7884 individually encrypted message;
7885 other recipients will continue to receive the message in plain text
7887 .Va smime-force-encryption
7889 It is recommended to sign encrypted messages, i.e., to also set the
7894 .It Va smime-force-encryption
7895 \*(BO\*(OP Causes \*(UA to refuse sending unencrypted messages.
7898 .It Va smime-no-default-ca
7899 \*(BO\*(OP Don't load default CA locations when verifying S/MIME signed
7904 \*(BO\*(OP S/MIME sign outgoing messages with the user's private key
7905 and include the user's certificate as a MIME attachment.
7906 Signing a message enables a recipient to verify that the sender used
7907 a valid certificate,
7908 that the email addresses in the certificate match those in the message
7909 header and that the message content has not been altered.
7910 It does not change the message text,
7911 and people will be able to read the message as usual.
7913 .Va smime-sign-cert , smime-sign-include-certs
7915 .Va smime-sign-message-digest .
7917 .Mx Va smime-sign-cert
7918 .It Va smime-sign-cert-USER@HOST , smime-sign-cert
7919 \*(OP Points to a file in PEM format.
7920 For the purpose of signing and decryption this file needs to contain the
7921 user's private key as well as his certificate.
7925 is always derived from the value of
7927 (or, if that contains multiple addresses,
7929 For the purpose of encryption the recipient's public encryption key
7930 (certificate) is expected; the command
7932 can be used to save certificates of signed messages (the section
7933 .Sx "Signed and encrypted messages with S/MIME"
7934 gives some details).
7935 This mode of operation is usually driven by the specialized form.
7937 When decrypting messages the account is derived from the recipient
7942 of the message, which are searched for addresses for which such
7944 \*(UA always uses the first address that matches,
7945 so if the same message is sent to more than one of the user's addresses
7946 using different encryption keys, decryption might fail.
7948 .Mx Va smime-sign-include-certs
7949 .It Va smime-sign-include-certs-USER@HOST , smime-sign-include-certs
7950 \*(OP If used, this is supposed to a consist of a comma-separated list
7951 of files, each of which containing a single certificate in PEM format to
7952 be included in the S/MIME message in addition to the
7955 This is most useful for long certificate chains if it is desired to aid
7956 the receiving party's verification process.
7957 Note that top level certificates may also be included in the chain but
7958 don't play a role for verification.
7960 .Va smime-sign-cert .
7961 Remember that for this
7963 refers to the variable
7965 (or, if that contains multiple addresses,
7968 .Mx Va smime-sign-message-digest
7969 .It Va smime-sign-message-digest-USER@HOST , smime-sign-message-digest
7970 \*(OP Specifies the message digest to use when signing S/MIME messages.
7971 RFC 5751 mandates a default of
7973 Possible values are (case-insensitive and) in decreasing cipher strength:
7981 The actually available message digest algorithms depend on the
7982 cryptographic library that \*(UA uses.
7983 \*(OP Support for more message digest algorithms may be available
7984 through dynamic loading via, e.g.,
7985 .Xr EVP_get_digestbyname 3
7986 (OpenSSL) if \*(UA has been compiled to support this.
7987 Remember that for this
7989 refers to the variable
7991 (or, if that contains multiple addresses,
7996 \*(OB\*(OP To use the builtin SMTP transport, specify a SMTP URL in
7998 \*(ID For compatibility reasons a set
8000 is used in preference of
8004 .It Va smtp-auth-USER@HOST , smtp-auth-HOST , smtp-auth
8005 \*(OP Variable chain that controls the SMTP
8007 authentication method, possible values are
8013 as well as the \*(OPal methods
8019 method doesn't need any user credentials,
8021 requires a user name and all other methods require a user name and
8029 .Va smtp-auth-password
8031 .Va smtp-auth-user ) .
8036 .Va smtp-auth-USER@HOST :
8037 may override dependent on sender address in the variable
8040 .It Va smtp-auth-password
8041 \*(OP\*(OU Sets the global fallback password for SMTP authentication.
8042 If the authentication method requires a password, but neither
8043 .Va smtp-auth-password
8045 .Va smtp-auth-password-USER@HOST
8047 \*(UA will ask for a password on the user's terminal.
8049 .It Va smtp-auth-password-USER@HOST
8051 .Va smtp-auth-password
8052 for specific values of sender addresses, dependent upon the variable
8055 .It Va smtp-auth-user
8056 \*(OP\*(OU Sets the global fallback user name for SMTP authentication.
8057 If the authentication method requires a user name, but neither
8060 .Va smtp-auth-user-USER@HOST
8062 \*(UA will ask for a user name on the user's terminal.
8064 .It Va smtp-auth-user-USER@HOST
8067 for specific values of sender addresses, dependent upon the variable
8071 .It Va smtp-hostname
8072 \*(OP\*(IN Normally \*(UA uses the variable
8074 to derive the necessary
8076 information in order to issue a
8083 can be used to use the
8085 from the SMTP account
8092 from the content of this variable (or, if that is the empty string,
8094 or the local hostname as a last resort).
8095 This often allows using an address that is itself valid but hosted by
8096 a provider other than which (in
8098 is about to send the message.
8099 Setting this variable also influences the generated
8102 .Mx Va smtp-use-starttls
8103 .It Va smtp-use-starttls-USER@HOST , smtp-use-starttls-HOST , smtp-use-starttls
8104 \*(BO\*(OP Causes \*(UA to issue a
8106 command to make an SMTP
8108 session SSL/TLS encrypted, i.e., to enable transport layer security.
8112 .It Va spam-interface
8113 \*(OP In order to use any of the spam-related commands (like, e.g.,
8115 the desired spam interface must be defined by setting this variable.
8116 Please refer to the manual section
8118 for the complete picture of spam handling in \*(UA.
8119 All or none of the following interfaces may be available:
8121 .Bl -tag -width ".It Ql _ilte_"
8127 .Pf ( Lk http://spamassassin.apache.org SpamAssassin )
8129 Different to the generic filter interface \*(UA will automatically add
8130 the correct arguments for a given command and has the necessary
8131 knowledge to parse the program's output.
8134 will have been compiled into the \*(UA binary if
8139 Shall it be necessary to define a specific connection type (rather than
8140 using a configuration file for that), the variable
8142 can be used as in, e.g.,
8143 .Ql -d server.example.com -p 783 .
8144 It is also possible to specify a per-user configuration via
8146 Note that this interface doesn't inspect the
8148 flag of a message for the command
8152 generic spam filter support via freely configurable hooks.
8153 This interface is meant for programs like
8155 and requires according behaviour in respect to the hooks' exit
8156 status for at least the command
8159 meaning a message is spam,
8163 for unsure and any other return value indicating a hard error);
8164 since the hooks can include shell code snippets diverting behaviour
8165 can be intercepted as necessary.
8167 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
8170 .Va spamfilter-spam ;
8173 contains examples for some programs.
8174 The process environment of the hooks will have the variables
8175 .Ev NAIL_TMPDIR , TMPDIR
8177 .Ev NAIL_FILENAME_GENERATED
8179 Note that spam score support for
8181 isn't supported unless the \*(OPtional regular expression support is
8183 .Va spamfilter-rate-scanscore
8190 \*(OP Messages that exceed this size won't be passed through to the
8192 .Va spam-interface .
8193 If unset or 0, the default of 420000 bytes is used.
8196 .It Va spamc-command
8197 \*(OP The path to the
8201 .Va spam-interface .
8202 Note that the path is not expanded, but used
8204 A fallback path will have been compiled into the \*(UA binary if the
8205 executable had been found during compilation.
8208 .It Va spamc-arguments
8209 \*(OP Even though \*(UA deals with most arguments for the
8212 automatically, it may at least sometimes be desirable to specify
8213 connection-related ones via this variable, e.g.,
8214 .Ql -d server.example.com -p 783 .
8218 \*(OP Specify a username for per-user configuration files for the
8220 .Va spam-interface .
8221 If this is set to the empty string then \*(UA will use the name of the
8230 .It Va spamfilter-ham , spamfilter-noham , \
8231 spamfilter-nospam , spamfilter-rate , spamfilter-spam
8232 \*(OP Command and argument hooks for the
8234 .Va spam-interface .
8237 contains examples for some programs.
8240 .It Va spamfilter-rate-scanscore
8241 \*(OP Because of the generic nature of the
8244 spam scores are not supported for it by default, but if the \*(OPtional
8245 regular expression support is available then setting this variable can
8246 be used to overcome this restriction.
8247 It is interpreted as follows: first a number (digits) is parsed that
8248 must be followed by a semicolon
8250 and an extended regular expression.
8251 Then the latter is used to parse the first output line of the
8253 hook, and, in case the evaluation is successful, the group that has been
8254 specified via the number is interpreted as a floating point scan score.
8258 \*(OP Specifies a directory with CA certificates in PEM (Pricacy
8259 Enhanced Mail) for verification of of SSL/TLS server certificates.
8261 .Xr SSL_CTX_load_verify_locations 3
8262 for more information.
8266 \*(OP Specifies a file with CA certificates in PEM format for
8267 verification of SSL/TLS server certificates.
8269 .Xr SSL_CTX_load_verify_locations 3
8270 for more information.
8273 .It Va ssl-cert-USER@HOST , ssl-cert-HOST , ssl-cert
8274 \*(OP Variable chain that sets the file name for a SSL/TLS client
8275 certificate required by some servers.
8276 This is a direct interface to the
8280 function of the OpenSSL library, if available.
8282 .Mx Va ssl-cipher-list
8283 .It Va ssl-cipher-list-USER@HOST , ssl-cipher-list-HOST , ssl-cipher-list
8284 \*(OP Specifies a list of ciphers for SSL/TLS connections.
8285 This is a direct interface to the
8289 function of the OpenSSL library, if available; see
8291 for more information.
8292 By default \*(UA doesn't set a list of ciphers, which in effect will use a
8294 specific cipher (protocol standards ship with a list of acceptable
8295 ciphers), possibly cramped to what the actually used SSL/TLS library
8296 supports \(en the manual section
8297 .Sx "An example configuration"
8298 also contains a SSL/TLS use case.
8301 .It Va ssl-config-file
8302 \*(OP If this variable is set \*(UA will call
8303 .Xr CONF_modules_load_file 3
8304 to allow OpenSSL to be configured according to the host system wide
8306 If a non-empty value is given then this will be used to specify the
8307 configuration file to be used instead of the global OpenSSL default;
8308 note that in this case it is an error if the file cannot be loaded.
8309 The application name will always be passed as
8314 \*(OP Specifies a file that contains a CRL in PEM format to use when
8315 verifying SSL/TLS server certificates.
8319 \*(OP Specifies a directory that contains files with CRLs in PEM format
8320 to use when verifying SSL/TLS server certificates.
8323 .It Va ssl-key-USER@HOST , ssl-key-HOST , ssl-key
8324 \*(OP Variable chain that sets the file name for the private key of
8325 a SSL/TLS client certificate.
8326 If unset, the name of the certificate file is used.
8327 The file is expected to be in PEM format.
8328 This is a direct interface to the
8332 function of the OpenSSL library, if available.
8335 .It Va ssl-method-USER@HOST , ssl-method-HOST , ssl-method
8336 \*(OB\*(OP Please use the newer and more flexible
8338 instead: if both values are set,
8340 will take precedence!
8341 Can be set to the following values, the actually used
8343 specification to which it is mapped is shown in parenthesis:
8345 .Pf ( Ql -ALL, TLSv1.2 ) ,
8347 .Pf ( Ql -ALL, TLSv1.1 ) ,
8349 .Pf ( Ql -ALL, TLSv1 )
8352 .Pf ( Ql -ALL, SSLv3 ) ;
8357 and thus includes the SSLv3 protocol.
8358 Note that SSLv2 is no longer supported at all.
8361 .It Va ssl-no-default-ca
8362 \*(BO\*(OP Don't load default CA locations to verify SSL/TLS server
8366 .It Va ssl-protocol-USER@HOST , ssl-protocol-HOST , ssl-protocol
8367 \*(OP Specify the used SSL/TLS protocol.
8368 This is a direct interface to the
8372 function of the OpenSSL library, if available;
8373 otherwise an \*(UA internal parser is used which understands the
8374 following subset of (case-insensitive) command strings:
8380 as well as the special value
8382 Multiple specifications may be given via a comma-separated list which
8383 ignores any whitespace.
8386 plus prefix will enable a protocol, a
8388 minus prefix will disable it, so that
8390 will enable only the TLSv1.2 protocol.
8392 It depends upon the used TLS/SSL library which protocols are actually
8393 supported and which protocols are used if
8395 is not set, but note that SSLv2 is no longer supported at all and
8397 Especially for older protocols explicitly securing
8399 may be worthwile, see
8400 .Sx "An example configuration" .
8404 \*(OP Gives the pathname to an entropy daemon socket, see
8406 Not all SSL/TLS libraries support this.
8409 .It Va ssl-rand-file
8410 \*(OP Gives the filename to a file with random entropy data, see
8411 .Xr RAND_load_file 3 .
8412 If this variable is not set, or set to the empty string, or if the
8413 filename expansion failed, then
8414 .Xr RAND_file_name 3
8415 will be used to create the filename if, and only if,
8417 documents that the SSL PRNG is not yet sufficiently seeded.
8418 If \*(UA successfully seeded the SSL PRNG then it'll update the file via
8419 .Xr RAND_write_file 3 .
8420 This variable is only used if
8422 is not set (or not supported by the SSL/TLS library).
8425 .It Va ssl-verify-USER@HOST , ssl-verify-HOST , ssl-verify
8426 \*(OP Variable chain that sets the action to be performed if an error
8427 occurs during SSL/TLS server certificate validation.
8428 Valid (case-insensitive) values are
8430 (fail and close connection immediately),
8432 (ask whether to continue on standard input),
8434 (show a warning and continue),
8436 (do not perform validation).
8442 If only set without an assigned value, then this option inhibits the
8447 header fields that include obvious references to \*(UA.
8448 There are two pitfalls associated with this:
8449 First, the message id of outgoing messages is not known anymore.
8450 Second, an expert may still use the remaining information in the header
8451 to track down the originating mail user agent.
8456 suppression doesn't occur.
8461 (\*(OP) This specifies a comma-separated list of
8466 .Sx "On terminal control and line editor" ,
8467 escape commas with reverse solidus) to be used to overwrite or define
8469 Note that this variable will only be queried once at program startup and
8470 can thus only be specified in resource files or on the command line.
8473 String capabilities form
8475 pairs and are expected unless noted otherwise.
8476 Numerics have to be notated as
8478 where the number is expected in normal decimal notation.
8479 Finally, booleans don't have any value but indicate a true or false
8480 state simply by being defined or not; this indeed means that \*(UA
8481 doesn't support undefining an existing boolean.
8482 String capability values will undergo some expansions before use:
8483 for one notations like
8486 .Ql control-LETTER ,
8487 and for clarification purposes
8489 can be used to specify
8491 (the control notation
8493 could lead to misreadings when a left bracket follows, which it does for
8494 the standard CSI sequence);
8495 finally three letter octal sequences, as in
8498 To specify that a terminal supports 256-colours, and to define sequences
8499 that home the cursor and produce an audible bell, one might write:
8501 .Bd -literal -offset indent
8502 set termcap='Co#256,home=\eE[H,bel=^G'
8506 The following terminal capabilities are or may be meaningful for the
8507 operation of the builtin line editor or \*(UA in general:
8510 .Bl -tag -compact -width yay
8512 .It Cd colors Ns \0or Cd Co
8514 numeric capability specifying the maximum number of colours.
8515 Note that \*(UA doesn't actually care about the terminal beside that,
8516 but always emits ANSI / ISO 6429 escape sequences.
8519 .It Cd rmcup Ns \0or Cd te Ns \0/ Cd smcup Ns \0or Cd ti
8523 respectively: exit and enter the alternative screen
8525 effectively turning \*(UA into a fullscreen application.
8526 To disable that, set (at least) one to the empty string.
8528 .It Cd smkx Ns \0or Cd ks Ns \0/ Cd rmkx Ns \0or Cd ke
8532 respectively: enable and disable the keypad.
8533 This is always enabled if available, because it seems even keyboards
8534 without keypads generate other key codes for, e.g., cursor keys in that
8535 case, and only if enabled we see the codes that we are interested in.
8537 .It Cd ed Ns \0or Cd cd
8541 .It Cd clear Ns \0or Cd cl
8543 clear the screen and home cursor.
8544 (Will be simulated via
8549 .It Cd home Ns \0or Cd ho
8554 .It Cd el Ns \0or Cd ce
8556 clear to the end of line.
8557 (Will be simulated via
8559 plus repetitions of space characters.)
8561 .It Cd hpa Ns \0or Cd ch
8562 .Cd column_address :
8563 move the cursor (to the given column parameter) in the current row.
8564 (Will be simulated via
8570 .Cd carriage_return :
8571 move to the first column in the current row.
8572 The default builtin fallback is
8575 .It Cd cub1 Ns \0or Cd le
8577 move the cursor left one space (non-destructively).
8578 The default builtin fallback is
8581 .It Cd cuf1 Ns \0or Cd nd
8583 move the cursor right one space (non-destructively).
8584 The default builtin fallback is
8586 which is used by most terminals.
8594 Many more capabilities which describe key-sequences are documented for
8598 .It Va termcap-disable
8599 \*(OP Disable any interaction with a terminal control library.
8600 If set only some generic fallback builtins and possibly the content of
8602 describe the terminal to \*(UA.
8604 that this variable will only be queried once at program startup and can
8605 thus only be specified in resource files or on the command line.
8609 If defined, gives the number of lines of a message to be displayed
8612 if unset, the first five lines are printed, if set to 0 the variable
8615 If the value is negative then its absolute value will be used for right
8618 height; (shifting bitwise is like dividing algorithmically, but since
8619 it takes away bits the value decreases pretty fast).
8623 \*(BO If set then the
8625 command series will strip adjacent empty lines and quotations.
8629 The character set of the terminal \*(UA operates on,
8630 and the one and only supported character set that \*(UA can use if no
8631 character set conversion capabilities have been compiled into it,
8632 in which case it defaults to ISO-8859-1 unless it can deduce a value
8636 Refer to the section
8637 .Sx "Character sets"
8638 for the complete picture about character sets.
8642 For a safety-by-default policy \*(UA sets its process
8646 but this variable can be used to override that:
8647 set it to an empty value to don't change the (current) setting,
8648 otherwise the process file mode creation mask is updated to the new value.
8649 Child processes inherit the process file mode creation mask.
8652 .It Va user-HOST , user
8653 \*(IN Variable chain that sets a global fallback user name, which is
8654 used in case none has been given in the protocol and account-specific
8656 This variable defaults to the name of the user who runs \*(UA.
8660 \*(BO Setting this option enables upward compatibility with \*(UA
8661 version 15.0 in respect to which configuration options are available and
8662 how they are handled.
8663 This manual uses \*(IN and \*(OU to refer to the new and the old way of
8664 doing things, respectively.
8668 \*(BO Setting this option, also controllable via the command line option
8670 causes \*(UA to be more verbose, e.g., it will display obsoletion
8671 warnings and SSL/TLS certificate chains.
8672 Even though marked \*(BO this option may be set twice in order to
8673 increase the level of verbosity even more, in which case even details of
8674 the actual message delivery and protocol conversations are shown.
8677 is sufficient to disable verbosity as such.
8683 .It Va version , version-major , version-minor , version-update
8684 \*(RO \*(UA version information: the first variable contains a string
8685 containing the complete version identification, the latter three contain
8686 only digits: the major, minor and update version numbers.
8687 The output of the command
8689 will include this information.
8692 .It Va writebackedited
8693 If this variable is set messages modified using the
8697 commands are written back to the current folder when it is quit;
8698 it is only honoured for writable folders in MBOX format, though.
8699 Note that the editor will be pointed to the raw message content in that
8700 case, i.e., neither MIME decoding nor decryption will have been
8701 performed, and proper RFC 4155
8703 quoting of newly added or edited content is also left as an excercise to
8707 .\" }}} (INTERNAL VARIABLES)
8710 .\" .Sh ENVIRONMENT {{{
8714 .Dq environment variable
8715 should be considered an indication that these variables are either
8716 standardized as vivid parts of process environments, or that they are
8717 commonly found in there.
8718 The process environment is inherited from the
8720 once \*(UA is started, and unless otherwise explicitly noted handling of
8721 the following variables transparently integrates into that of the
8722 .Sx "INTERNAL VARIABLES"
8723 from \*(UA's point of view.
8724 This means that, e.g., they can be managed via
8728 causing automatic program environment updates (to be inherited by
8729 newly created child processes).
8732 In order to transparently integrate other environment variables equally
8733 they need to be imported (linked) with the command
8735 This command can also be used to set and unset non-integrated
8736 environment variables from scratch, sufficient system support provided.
8737 The following example, applicable to a POSIX shell, sets the
8739 environment variable for \*(UA only, and beforehand exports the
8741 in order to affect any further processing in the running shell:
8743 .Bd -literal -offset indent
8744 $ EDITOR="vim -u ${HOME}/.vimrc"
8746 $ COLUMNS=80 \*(uA -R
8749 .Bl -tag -width ".It Ev _AILR_"
8752 The user's preferred width in column positions for the terminal screen
8754 Queried and used once on program startup, actively managed for child
8755 processes and the MLE (see
8756 .Sx "On terminal control and line editor" )
8757 in interactive mode thereafter.
8761 The name of the (mailbox)
8763 to use for saving aborted messages if
8765 is set; this defaults to
8772 is set no output will be generated, otherwise the contents of the file
8777 Pathname of the text editor to use in the
8781 .Sx "TILDE ESCAPES" .
8782 A default editor is used if this value is not defined.
8786 The user's home directory.
8787 This variable is only used when it resides in the process environment.
8794 .It Ev LANG , LC_ALL , LC_COLLATE , LC_CTYPE , LC_MESSAGES
8798 .Sx "Character sets" .
8802 The user's preferred number of lines on a page or the vertical screen
8803 or window size in lines.
8804 Queried and used once on program startup, actively managed for child
8805 processes in interactive mode thereafter.
8809 Pathname of the directory lister to use in the
8811 command when operating on local mailboxes.
8814 (path search through
8819 Upon startup \*(UA will actively ensure that this variable refers to the
8820 name of the user who runs \*(UA, in order to be able to pass a verified
8821 name to any newly created child process.
8825 Is used as the user's primary system mailbox, if set.
8826 Otherwise, a system-dependent default is used.
8827 Supports the special syntax conventions that are documented for the
8833 \*(OP Overrides the default path search for
8834 .Sx "The Mailcap files" ,
8835 which is defined in the standard RFC 1524 as
8836 .Ql ~/.mailcap:\:/etc/mailcap:\:/usr/etc/mailcap:\:/usr/local/etc/mailcap .
8837 .\" TODO we should have a mailcaps-default virtual RDONLY option!
8838 (\*(UA makes it a configuration option, however.)
8839 Note this is not a search path, but a path search.
8843 Is used as a startup file instead of
8846 When \*(UA scripts are invoked on behalf of other users,
8847 either this variable should be set to
8851 command line option should be used in order to avoid side-effects from
8852 reading their configuration files.
8853 This variable is only used when it resides in the process environment.
8857 The name of the user's mbox file.
8858 A logical subset of the special conventions that are documented for the
8863 The fallback default is
8868 Traditionally this secondary mailbox is used as the file to save
8869 messages from the primary system mailbox that have been read.
8871 .Sx "Message states" .
8874 .It Ev NAIL_NO_SYSTEM_RC
8875 If this variable is set then reading of
8877 at startup is inhibited, i.e., the same effect is achieved as if \*(UA
8878 had been started up with the option
8880 This variable is only used when it resides in the process environment.
8884 \*(IN\*(OP This variable overrides the default location of the user's
8890 Pathname of the program to use for backing the command
8894 variable enforces usage of a pager for output.
8895 The default paginator is
8897 (path search through
8900 \*(UA inspects the contents of this variable: if its contains the string
8902 then a non-existing environment variable
8909 dependent on whether terminal control support is available and whether
8910 that supports full (alternative) screen mode or not (also see
8911 .Sx "On terminal control and line editor" ) .
8915 will optionally be set to
8922 A colon-separated list of directories that is searched by the shell when
8923 looking for commands, e.g.,
8924 .Ql /bin:/usr/bin:/usr/local/bin .
8928 The shell to use for the commands
8934 and when starting subprocesses.
8935 A default shell is used if this option is not defined.
8938 .It Ev SOURCE_DATE_EPOCH
8939 If set, this specifies a time in seconds since the Unix epoch
8940 (1970-01-01) to be used in place of the current time.
8941 This is for the sake of reproduceability of tests, to be used during
8942 development or by software packagers.
8946 \*(OP The terminal type for which output is to be prepared.
8947 For extended colour and font control please refer to
8948 .Sx "Coloured display" ,
8949 and for terminal management in general to
8950 .Sx "On terminal control and line editor" .
8954 Used as directory for temporary files instead of
8957 This variable is only used when it resides in the process environment.
8963 (see there), but this variable is not standardized, should therefore not
8964 be used, and is only corrected if already set.
8968 Pathname of the text editor to use in the
8972 .Sx "TILDE ESCAPES" .
8980 .Bl -tag -width ".It Pa _etc/mime.type_"
8982 File giving initial commands.
8985 System wide initialization file.
8989 \*(OP Personal MIME type handler definition file, see
8990 .Sx "The Mailcap files" .
8991 (RFC 1524 location, the actual path is a configuration option.)
8995 \*(OP System wide MIME type handler definition file, see
8996 .Sx "The Mailcap files" .
8997 (RFC 1524 location, the actual path is a configuration option.)
9000 .It Pa ~/.mime.types
9001 Personal MIME types, see
9002 .Sx "The mime.types files" .
9005 .It Pa /etc/mime.types
9006 System wide MIME types, see
9007 .Sx "The mime.types files" .
9011 \*(IN\*(OP The default location of the users
9013 file \(en the section
9014 .Sx "The .netrc file"
9015 documents the file format.
9018 .\" .Ss "The mime.types files" {{{
9019 .Ss "The mime.types files"
9021 When sending messages \*(UA tries to determine the content type of all
9023 When displaying message content or attachments \*(UA uses the content
9024 type to decide whether it can directly display data or whether it needs
9025 to deal with content handlers.
9026 It learns about MIME types and how to treat them by reading
9028 files, the loading of which can be controlled by setting the variable
9029 .Va mimetypes-load-control .
9032 can also be used to deal with MIME types.)
9034 files have the following syntax:
9037 .Dl type/subtype extension [extension ...]
9042 are strings describing the file contents, and one or multiple
9044 s, separated by whitespace, name the part of a filename starting after
9045 the last dot (of interest).
9046 Comments may be introduced anywhere on a line with a number sign
9048 causing the remaining line to be discarded.
9050 \*(UA also supports an extended, non-portable syntax in specially
9051 crafted files, which can be loaded via the alternative value syntax of
9052 .Va mimetypes-load-control
9053 and prepends an optional
9057 .Dl [type-marker ]type/subtype extension [extension ...]
9060 The following type markers are supported:
9063 .Bl -tag -compact -offset indent -width ".It Ar _n_u"
9065 Treat message parts with this content as plain text.
9070 Treat message parts with this content as HTML tagsoup.
9071 If the \*(OPal HTML-tagsoup-to-text converter is not available treat
9072 the content as plain text instead.
9076 but instead of falling back to plain text require an explicit content
9077 handler to be defined.
9082 for sending messages:
9084 .Va mime-allow-text-controls ,
9085 .Va mimetypes-load-control .
9086 For reading etc. messages:
9087 .Sx "HTML mail and MIME attachments" ,
9088 .Sx "The Mailcap files" ,
9090 .Va mime-counter-evidence ,
9091 .Va mimetypes-load-control ,
9092 .Va pipe-TYPE/SUBTYPE ,
9093 .Va pipe-EXTENSION .
9096 .\" .Ss "The Mailcap files" {{{
9097 .Ss "The Mailcap files"
9100 .Dq User Agent Configuration Mechanism
9101 which \*(UA \*(OPally supports.
9102 It defines a file format to be used to inform mail user agent programs
9103 about the locally-installed facilities for handling various data
9104 formats, i.e., about commands and how they can be used to display, edit
9105 etc. MIME part contents, as well as a default path search that includes
9106 multiple possible locations of
9110 environment variable that can be used to overwrite that (repeating here
9111 that it is not a search path, but instead a path search specification).
9112 Any existing files will be loaded in sequence, appending any content to
9113 the list of MIME type handler directives.
9117 files consist of a set of newline separated entries.
9118 Comment lines start with a number sign
9120 (in the first column!) and are ignored.
9121 Empty lines are also ignored.
9122 All other lines form individual entries that must adhere to the syntax
9124 To extend a single entry (not comment) its line can be continued on
9125 follow lines if newline characters are
9127 by preceding them with the reverse solidus character
9129 The standard doesn't specify how leading whitespace of follow lines is
9130 to be treated, therefore \*(UA retains it.
9134 entries consist of a number of semicolon
9136 separated fields, and the reverse solidus
9138 character can be used to escape any following character including
9139 semicolon and itself.
9140 The first two fields are mandatory and must occur in the specified
9141 order, the remaining fields are optional and may appear in any order.
9142 Leading and trailing whitespace of content is ignored (removed).
9145 The first field defines the MIME
9147 the entry is about to handle (case-insensitively, and no reverse solidus
9148 escaping is possible in this field).
9149 If the subtype is specified as an asterisk
9151 the entry is meant to match all subtypes of the named type, e.g.,
9153 would match any audio type.
9154 The second field defines the shell command which shall be used to
9156 MIME parts of the given type; it is implicitly called the
9163 shell commands message (MIME part) data is passed via standard input
9164 unless the given shell command includes one or more instances of the
9167 in which case these instances will be replaced with a temporary filename
9168 and the data will have been stored in the file that is being pointed to.
9171 shell commands data is assumed to be generated on standard output unless
9172 the given command includes (one ore multiple)
9174 In any case any given
9176 format is replaced with a(n already) properly quoted filename.
9177 Note that when a command makes use of a temporary file via
9179 then \*(UA will remove it again, as if the
9180 .Cd x-mailx-tmpfile ,
9181 .Cd x-mailx-tmpfile-fill
9183 .Cd x-mailx-tmpfile-unlink
9184 flags had been set; see below for more.
9187 The optional fields either define a shell command or an attribute (flag)
9188 value, the latter being a single word and the former being a keyword
9189 naming the field followed by an equals sign
9191 succeeded by a shell command, and as usual for any
9193 content any whitespace surrounding the equals sign will be removed, too.
9194 Optional fields include the following:
9197 .Bl -tag -width textualnewlines
9199 A program that can be used to compose a new body or body part in the
9206 field, but is to be used when the composing program needs to specify the
9208 header field to be applied to the composed data.
9212 A program that can be used to edit a body or body part in the given
9217 A program that can be used to print a message or body part in the given
9222 Specifies a program to be run to test some condition, e.g., the machine
9223 architecture, or the window system in use, to determine whether or not
9224 this mailcap entry applies.
9225 If the test fails, a subsequent mailcap entry should be sought; also see
9226 .Cd x-mailx-test-once .
9228 .It Cd needsterminal
9229 This flag field indicates that the given shell command must be run on
9230 an interactive terminal.
9231 \*(UA will temporarily release the terminal to the given command in
9232 interactive mode, in non-interactive mode this entry will be entirely
9233 ignored; this flag implies
9234 .Cd x-mailx-noquote .
9236 .It Cd copiousoutput
9237 A flag field which indicates that the output of the
9239 command will be an extended stream of textual output that can be
9240 (re)integrated into \*(UA's normal visual display.
9241 It is mutually exclusive with
9244 .Cd x-mailx-always .
9246 .It Cd textualnewlines
9247 A flag field which indicates that this type of data is line-oriented and
9250 all newlines should be converted to canonical form (CRLF) before
9251 encoding, and will be in that form after decoding.
9255 This field gives a file name format, in which
9257 will be replaced by a random string, the joined combination of which
9258 will be used as the filename denoted by
9259 .Ev NAIL_FILENAME_TEMPORARY .
9260 One could specify that a GIF file being passed to an image viewer should
9261 have a name ending in
9264 .Ql nametemplate=%s.gif .
9265 Note that \*(UA ignores the name template unless that solely specifies
9266 a filename suffix that consists of (ASCII) alphabetic and numeric
9267 characters, the underscore and dot only.
9270 Names a file, in X11 bitmap (xbm) format, which points to an appropriate
9271 icon to be used to visually denote the presence of this kind of data.
9272 This field is not used by \*(UA.
9275 A textual description that describes this type of data.
9277 .It Cd x-mailx-always
9278 Extension flag field that denotes that the given
9280 command shall be executed even if multiple messages will be displayed
9282 Normally messages which require external viewers that produce output
9283 which doesn't integrate into \*(UA's visual display (i.e., don't have
9285 set) have to be addressed directly and individually.
9286 (To avoid cases where, e.g., a thousand PDF viewer instances are spawned
9289 .It Cd x-mailx-even-if-not-interactive
9290 An extension flag test field \(em by default handlers without
9292 are entirely ignored in non-interactive mode, but if this flag is set
9293 then their use will be considered.
9294 It is an error if this flag is set for commands that use the flag
9297 .It Cd x-mailx-noquote
9298 An extension flag field that indicates that even a
9301 command shall not be used to generate message quotes
9302 (as it would be by default).
9304 .It Cd x-mailx-async
9305 Extension flag field that denotes that the given
9307 command shall be executed asynchronously, without blocking \*(UA.
9308 Cannot be used in conjunction with
9311 .It Cd x-mailx-test-once
9312 Extension flag which denotes whether the given
9314 command shall be evaluated once only and the (boolean) result be cached.
9315 This is handy if some global unchanging condition is to be queried, like
9316 .Dq running under the X Window System .
9318 .It Cd x-mailx-tmpfile
9319 Extension flag field that requests creation of a zero-sized temporary
9320 file, the name of which is to be placed in the environment variable
9321 .Ev NAIL_FILENAME_TEMPORARY .
9322 It is an error to use this flag with commands that include a
9326 .It Cd x-mailx-tmpfile-fill
9327 Normally the MIME part content is passed to the handler via standard
9328 input; if this flag is set then the data will instead be written into
9330 .Cd x-mailx-tmpfile .
9331 In order to cause deletion of the temporary file you will have to set
9332 .Cd x-mailx-tmpfile-unlink
9334 It is an error to use this flag with commands that include a
9338 .It Cd x-mailx-tmpfile-unlink
9339 Extension flag field that requests that the temporary file shall be
9340 deleted automatically when the command loop is entered again at latest.
9341 (Don't use this for asynchronous handlers.)
9342 It is an error to use this flag with commands that include a
9344 format, or without also setting
9347 .Cd x-mailx-tmpfile-fill .
9349 .It Cd x-mailx-tmpfile-keep
9352 implies the three tmpfile related flags above, but if you want, e.g.,
9354 and deal with the temporary file yourself, you can add in this flag to
9356 .Cd x-mailx-tmpfile-unlink .
9361 The standard includes the possibility to define any number of additional
9362 entry fields, prefixed by
9364 Flag fields apply to the entire
9366 entry \(em in some unusual cases, this may not be desirable, but
9367 differentiation can be accomplished via separate entries, taking
9368 advantage of the fact that subsequent entries are searched if an earlier
9369 one does not provide enough information.
9372 command needs to specify the
9376 command shall not, the following will help out the latter (with enabled
9380 level \*(UA will show information about handler evaluation):
9382 .Bd -literal -offset indent
9383 application/postscript; ps-to-terminal %s; needsterminal
9384 application/postscript; ps-to-terminal %s; compose=idraw %s
9388 In fields any occurrence of the format string
9390 will be replaced by the
9393 Named parameters from the
9395 field may be placed in the command execution line using
9397 followed by the parameter name and a closing
9400 The entire parameter should appear as a single command line argument,
9401 regardless of embedded spaces; thus:
9403 .Bd -literal -offset indent
9405 Content-type: multipart/mixed; boundary=42
9408 multipart/*; /usr/local/bin/showmulti \e
9409 %t %{boundary} ; composetyped = /usr/local/bin/makemulti
9411 # Executed shell command
9412 /usr/local/bin/showmulti multipart/mixed 42
9416 .\" TODO v15: Mailcap: %n,%F
9417 Note that \*(UA doesn't support handlers for multipart MIME parts as
9418 shown in this example (as of today).
9419 \*(UA doesn't support the additional formats
9423 An example file, also showing how to properly deal with the expansion of
9425 which includes any quotes that are necessary to make it a valid shell
9426 argument by itself and thus will cause undesired behaviour when placed
9427 in additional user-provided quotes:
9429 .Bd -literal -offset indent
9431 text/richtext; richtext %s; copiousoutput
9433 text/x-perl; perl -cWT %s
9437 trap "rm -f ${infile}" EXIT\e; \e
9438 trap "exit 75" INT QUIT TERM\e; \e
9440 x-mailx-async; x-mailx-tmpfile-keep
9442 application/*; echo "This is \e"%t\e" but \e
9443 is 50 \e% Greek to me" \e; < %s head -c 1024 | cat -vET; \e
9444 copiousoutput; x-mailx-noquote
9449 .Sx "HTML mail and MIME attachments" ,
9450 .Sx "The mime.types files" ,
9453 .Va mime-counter-evidence ,
9454 .Va pipe-TYPE/SUBTYPE ,
9455 .Va pipe-EXTENSION .
9458 .\" .Ss "The .netrc file" {{{
9459 .Ss "The .netrc file"
9463 file contains user credentials for machine accounts.
9464 The default location in the user's
9466 directory may be overridden by the
9468 environment variable.
9469 The file consists of space, tabulator or newline separated tokens.
9470 \*(UA implements a parser that supports a superset of the original BSD
9471 syntax, but users should nonetheless be aware of portability glitches
9472 of that file format, shall their
9474 be usable across multiple programs and platforms:
9477 .Bl -bullet -compact
9479 BSD doesn't support single, but only double quotation marks, e.g.,
9480 .Ql password="pass with spaces" .
9482 BSD (only?) supports escaping of single characters via a reverse solidus
9483 (e.g., a space can be escaped via
9485 in- as well as outside of a quoted string.
9487 BSD doesn't require the final quotation mark of the final user input token.
9489 The original BSD (Berknet) parser also supported a format which allowed
9490 tokens to be separated with commas \(en whereas at least Hewlett-Packard
9491 still seems to support this syntax, \*(UA does not!
9493 As a non-portable extension some widely-used programs support
9494 shell-style comments: if an input line starts, after any amount of
9495 whitespace, with a number sign
9497 then the rest of the line is ignored.
9499 Whereas other programs may require that the
9501 file is accessible by only the user if it contains a
9507 \*(UA will always require these strict permissions.
9511 Of the following list of supported tokens \*(UA only uses (and caches)
9516 At runtime the command
9518 can be used to control \*(UA's
9522 .Bl -tag -width password
9523 .It Cd machine Ar name
9524 The hostname of the entries' machine, lowercase-normalized by \*(UA
9526 Any further file content, until either end-of-file or the occurrence
9531 first-class token is bound (only related) to the machine
9534 As an extension that shouldn't be the cause of any worries
9535 \*(UA supports a single wildcard prefix for
9537 .Bd -literal -offset indent
9538 machine *.example.com login USER password PASS
9539 machine pop3.example.com login USER password PASS
9540 machine smtp.example.com login USER password PASS
9546 .Ql pop3.example.com ,
9550 .Ql local.smtp.example.com .
9551 Note that in the example neither
9552 .Ql pop3.example.com
9554 .Ql smtp.example.com
9555 will be matched by the wildcard, since the exact matches take
9556 precedence (it is however faster to specify it the other way around).
9561 except that it is a fallback entry that is used shall none of the
9562 specified machines match; only one default token may be specified,
9563 and it must be the last first-class token.
9565 .It Cd login Ar name
9566 The user name on the remote machine.
9568 .It Cd password Ar string
9569 The user's password on the remote machine.
9571 .It Cd account Ar string
9572 Supply an additional account password.
9573 This is merely for FTP purposes.
9575 .It Cd macdef Ar name
9577 A macro is defined with the specified
9579 it is formed from all lines beginning with the next line and continuing
9580 until a blank line is (consecutive newline characters are) encountered.
9583 entries cannot be utilized by multiple machines, too, but must be
9584 defined following the
9586 they are intended to be used with.)
9589 exists, it is automatically run as the last step of the login process.
9590 This is merely for FTP purposes.
9597 .\" .Sh EXAMPLES {{{
9600 .\" .Ss "An example configuration" {{{
9601 .Ss "An example configuration"
9603 .Bd -literal -offset indent
9604 # This example assumes v15.0 compatibility mode
9607 # Where are the up-to-date SSL certificates?
9608 #set ssl-ca-dir=/etc/ssl/certs
9609 set ssl-ca-file=/etc/ssl/certs/ca-certificates.crt
9611 # (Since we manage up-to-date ones explicitly, don't use any,
9612 # possibly outdated, default certificates shipped with OpenSSL)
9613 set ssl-no-default-ca
9615 # Don't use protocols older than TLS v1.2.
9616 # Change this only when the remote server doesn't support it:
9617 # maybe use ssl-protocol-HOST (or -USER@HOST) syntax to define
9618 # such explicit exceptions, then
9619 set ssl-protocol='-ALL,+TLSv1.2'
9621 # Explicitly define the list of ciphers, which may improve security,
9622 # especially with protocols older than TLS v1.2. See ciphers(1).
9623 # Including "@STRENGTH" will sort the final list by algorithm strength.
9624 # In reality it is possibly best to only use ssl-cipher-list-HOST
9625 # (or -USER@HOST), as necessary, again..
9626 set ssl-cipher-list=TLSv1.2:!aNULL:!eNULL:!MEDIUM:!LOW:!EXPORT:@STRENGTH
9627 # ALL:!aNULL:!MEDIUM:!LOW:!MD5:!RC4:!EXPORT:@STRENGTH
9629 # Request strict transport security checks!
9630 set ssl-verify=strict
9632 # Essential setting: select allowed character sets
9633 set sendcharsets=utf-8,iso-8859-1
9635 # A very kind option: when replying to a message, first try to
9636 # use the same encoding that the original poster used herself!
9637 set reply-in-same-charset
9639 # When replying to or forwarding a message the comment and name
9640 # parts of email addresses are removed unless this variable is set
9643 # When sending messages, wait until the Mail-Transfer-Agent finishs.
9644 # Only like this you'll be able to see errors reported through the
9645 # exit status of the MTA (including the builtin SMTP one)!
9648 # Only use builtin MIME types, no mime.types(5) files
9649 set mimetypes-load-control
9651 # Default directory where we act in (relative to $HOME)
9653 # A leading "+" (often) means: under *folder*
9654 # *record* is used to save copies of sent messages
9655 set MBOX=+mbox.mbox record=+sent.mbox DEAD=+dead.txt
9657 # Make "file mymbox" and "file myrec" go to..
9658 shortcut mymbox %:+mbox.mbox myrec +sent.mbox
9660 # Not really optional, e.g., for S/MIME
9661 set from='Your Name <address@exam.ple>'
9663 # It may be necessary to set hostname and/or smtp-hostname
9664 # if the "SERVER" of mta and "domain" of from don't match.
9665 # The `urlencode' command can be used to encode USER and PASS
9666 set mta=(smtps?|submission)://[USER[:PASS]@]SERVER[:PORT] \e
9667 smtp-auth=login/plain... \e
9670 # Never refuse to start into interactive mode, and more
9672 colour-pager crt= \e
9673 followup-to followup-to-honour=ask-yes \e
9674 history-file=+.\*(uAhist history-size=-1 history-gabby \e
9675 mime-counter-evidence=0xE \e
9676 prompt='?\e?[\e$ \e@]\e& ' \e
9677 reply-to-honour=ask-yes \e
9680 # When `t'yping messages, show only these headers
9681 # (use `T'ype for all headers and `S'how for raw message)
9682 retain date from to cc subject
9684 # Some mailing lists
9685 mlist '@xyz-editor\e.xyz$' '@xyzf\e.xyz$'
9686 mlsubscribe '^xfans@xfans\e.xyz$'
9688 # A real life example of a very huge free mail provider
9690 set folder=~/spool/XooglX MAIL=+syste.mbox sent=+sent
9691 set from='Your Name <address@examp.ple>'
9692 set mta=smtp://USER:PASS@smtp.gmXil.com smtp-use-starttls
9695 # Here is a pretty large one which does not allow sending mails
9696 # if there is a domain name mismatch on the SMTP protocol level,
9697 # which would bite us if the value of from does not match, e.g.,
9698 # for people who have a sXXXXeforge project and want to speak
9699 # with the mailing list under their project account (in from),
9700 # still sending the message through their normal mail provider
9702 set folder=~/spool/XandeX MAIL=+syste.mbox sent=+sent
9703 set from='Your Name <address@exam.ple>'
9704 set mta=smtps://USER:PASS@smtp.yaXXex.ru:465 \e
9705 hostname=yaXXex.com smtp-hostname=
9708 # Create some new commands so that, e.g., `ls /tmp' will..
9709 wysh ghost lls '!ls ${LS_COLOR_FLAG} -aFlrS'
9710 wysh ghost llS '!ls ${LS_COLOR_FLAG} -aFlS'
9711 wysh ghost ls '!ls ${LS_COLOR_FLAG} -aFrS'
9712 wysh ghost lS '!ls ${LS_COLOR_FLAG} -aFS'
9713 wysh ghost lla '!ls ${LS_COLOR_FLAG} -aFlr'
9714 wysh ghost llA '!ls ${LS_COLOR_FLAG} -aFl'
9715 wysh ghost la '!ls ${LS_COLOR_FLAG} -aFr'
9716 wysh ghost lA '!ls ${LS_COLOR_FLAG} -aF'
9717 wysh ghost ll '!ls ${LS_COLOR_FLAG} -aFltr'
9718 wysh ghost lL '!ls ${LS_COLOR_FLAG} -aFlt'
9719 wysh ghost l '!ls ${LS_COLOR_FLAG} -aFtr'
9720 wysh ghost L '!ls ${LS_COLOR_FLAG} -aFt'
9722 # We don't support gpg(1) directly yet. But simple --clearsign'd
9723 # message parts can be dealt with as follows:
9725 wysh set pipe-text/plain=$'@*#++=@\e
9726 < "${NAIL_FILENAME_TEMPORARY}" awk \e
9727 -v TMPFILE="${NAIL_FILENAME_TEMPORARY}" \e'\e
9729 /^-----BEGIN PGP SIGNED MESSAGE-----/,/^$/{\e
9732 print "--- GPG --verify ---";\e
9733 system("gpg --verify " TMPFILE " 2>&1");\e
9734 print "--- GPG --verify ---";\e
9738 /^-----BEGIN PGP SIGNATURE-----/,\e
9739 /^-----END PGP SIGNATURE-----/{\e
9749 !printf 'Key IDs to gpg --recv-keys: ';\e
9751 gpg --recv-keys ${keyids};
9757 When storing passwords in
9759 appropriate permissions should be set on this file with
9760 .Ql $ chmod 0600 \*(ur .
9763 is available user credentials can be stored in the central
9765 file instead; e.g., here is a different version of the example account
9766 that sets up SMTP and POP3:
9768 .Bd -literal -offset indent
9770 set folder=~/spool/XandeX MAIL=+syste.mbox sent=+sent
9771 set from='Your Name <address@exam.ple>'
9773 # Load an encrypted ~/.netrc by uncommenting the next line
9774 #set netrc-pipe='gpg -qd ~/.netrc.pgp'
9776 set mta=smtps://smtp.yXXXXx.ru:465 \e
9777 smtp-hostname= hostname=yXXXXx.com
9778 set pop3-keepalive=240 pop3-no-apop-pop.yXXXXx.ru
9779 ghost xp fi pop3s://pop.yXXXXx.ru
9788 .Bd -literal -offset indent
9789 machine *.yXXXXx.ru login USER password PASS
9793 This configuration should now work just fine:
9796 .Dl $ echo text | \*(uA -vv -AXandeX -s Subject user@exam.ple
9799 .\" .Ss "Signed and encrypted messages with S/MIME" {{{
9800 .Ss "Signed and encrypted messages with S/MIME"
9802 \*(OP S/MIME provides two central mechanisms:
9803 message signing and message encryption.
9804 A signed message contains some data in addition to the regular text.
9805 The data can be used to verify that the message was sent using a valid
9806 certificate, that the sender's address in the message header matches
9807 that in the certificate, and that the message text has not been altered.
9808 Signing a message does not change its regular text;
9809 it can be read regardless of whether the recipient's software is able to
9813 It is thus usually possible to sign all outgoing messages if so desired.
9814 Encryption, in contrast, makes the message text invisible for all people
9815 except those who have access to the secret decryption key.
9816 To encrypt a message, the specific recipient's public encryption key
9818 It is therefore not possible to send encrypted mail to people unless their
9819 key has been retrieved from either previous communication or public key
9821 A message should always be signed before it is encrypted.
9822 Otherwise, it is still possible that the encrypted message text is
9826 A central concept to S/MIME is that of the certification authority (CA).
9827 A CA is a trusted institution that issues certificates.
9828 For each of these certificates it can be verified that it really
9829 originates from the CA, provided that the CA's own certificate is
9831 A set of CA certificates is usually delivered with OpenSSL and installed
9833 If you trust the source of your OpenSSL software installation,
9834 this offers reasonable security for S/MIME on the Internet.
9836 .Va ssl-no-default-ca
9840 .Va smime-ca-dir . )
9841 In general, a certificate cannot be more secure than the method its CA
9842 certificate has been retrieved with, though.
9843 Thus if you download a CA certificate from the Internet,
9844 you can only trust the messages you verify using that certificate as
9845 much as you trust the download process.
9848 The first thing you need for participating in S/MIME message exchange is
9849 your personal certificate, including a private key.
9850 The certificate contains public information, in particular your name and
9851 your email address(es), and the public key that is used by others to
9852 encrypt messages for you,
9853 and to verify signed messages they supposedly received from you.
9854 The certificate is included in each signed message you send.
9855 The private key must be kept secret.
9856 It is used to decrypt messages that were previously encrypted with your
9857 public key, and to sign messages.
9860 For personal use it is recommended that you get a S/MIME certificate
9861 from one of the major CAs on the Internet using your WWW browser.
9862 Many CAs offer such certificates for free.
9864 .Lk https://www.CAcert.org
9865 which issues client and server certificates to members of their
9866 community for free; their root certificate
9867 .Pf ( Lk https://\:www.cacert.org/\:certs/\:root.crt )
9868 is often not in the default set of trusted CA root certificates, though,
9869 which means you will have to download their root certificate separately
9870 and ensure it is part of our S/MIME certificate validation chain by
9873 or as a vivid member of the
9875 But let's take a step-by-step tour on how to setup S/MIME with
9876 a certificate from CAcert.org despite this situation!
9879 First of all you will have to become a member of the CAcert.org
9880 community, simply by registrating yourself via the web interface.
9881 Once you are, create and verify all email addresses you want to be able
9882 to create signed and encrypted messages for/with using the corresponding
9883 entries of the web interface.
9884 Now ready to create S/MIME certificates, so let's create a new
9885 .Dq client certificate ,
9886 ensure to include all email addresses that should be covered by the
9887 certificate in the following web form, and also to use your name as the
9891 Create a private key and a certificate request on your local computer
9892 (please see the manual pages of the used commands for more in-depth
9893 knowledge on what the used arguments etc. do):
9896 .Dl openssl req -nodes -newkey rsa:4096 -keyout key.pem -out creq.pem
9899 Afterwards copy-and-paste the content of
9901 into the certificate-request (CSR) field of the web form on the
9902 CAcert.org website (you may need to unfold some
9903 .Dq advanced options
9904 to see the corresponding text field).
9905 This last step will ensure that your private key (which never left your
9906 box) and the certificate belong together (through the public key that
9907 will find its way into the certificate via the certificate-request).
9908 You are now ready and can create your CAcert certified certificate.
9909 Download and store or copy-and-paste it as
9914 In order to use your new S/MIME setup you will have to create
9915 a combined private key/public key (certificate) file:
9918 .Dl cat key.pem pub.crt > ME@HERE.com.paired
9921 This is the file \*(UA will work with.
9922 If you have created your private key with a passphrase then \*(UA will
9923 ask you for it whenever a message is signed or decrypted.
9924 Set the following variables to henceforth use S/MIME (setting
9926 is of interest for verification only):
9928 .Bd -literal -offset indent
9929 set smime-ca-file=ALL-TRUSTED-ROOT-CERTS-HERE \e
9930 smime-sign-cert=ME@HERE.com.paired \e
9931 smime-sign-message-digest=SHA256 \e
9936 From each signed message you send, the recipient can fetch your
9937 certificate and use it to send encrypted mail back to you.
9938 Accordingly if somebody sends you a signed message, you can do the same,
9941 command to check the validity of the certificate.
9944 Variables of interest for S/MIME signing:
9948 .Va smime-crl-file ,
9949 .Va smime-no-default-ca ,
9951 .Va smime-sign-cert ,
9952 .Va smime-sign-include-certs
9954 .Va smime-sign-message-digest .
9957 After it has been verified save the certificate via
9959 and tell \*(UA that it should use it for encryption for further
9960 communication with that somebody:
9962 .Bd -literal -offset indent
9964 set smime-encrypt-USER@HOST=FILENAME \e
9965 smime-cipher-USER@HOST=AES256
9969 Additional variables of interest for S/MIME en- and decryption:
9972 .Va smime-encrypt-USER@HOST .
9975 You should carefully consider if you prefer to store encrypted messages
9977 If you do, anybody who has access to your mail folders can read them,
9978 but if you do not, you might be unable to read them yourself later if
9979 you happen to lose your private key.
9982 command saves messages in decrypted form, while the
9986 commands leave them encrypted.
9989 Note that neither S/MIME signing nor encryption applies to message
9990 subjects or other header fields yet.
9991 Thus they may not contain sensitive information for encrypted messages,
9992 and cannot be trusted even if the message content has been verified.
9993 When sending signed messages,
9994 it is recommended to repeat any important header information in the
9998 .\" .Ss "Using CRLs with S/MIME or SSL/TLS" {{{
9999 .Ss "Using CRLs with S/MIME or SSL/TLS"
10001 \*(OP Certification authorities (CAs) issue certificate revocation
10002 lists (CRLs) on a regular basis.
10003 These lists contain the serial numbers of certificates that have been
10004 declared invalid after they have been issued.
10005 Such usually happens because the private key for the certificate has
10007 because the owner of the certificate has left the organization that is
10008 mentioned in the certificate, etc.
10009 To seriously use S/MIME or SSL/TLS verification,
10010 an up-to-date CRL is required for each trusted CA.
10011 There is otherwise no method to distinguish between valid and
10012 invalidated certificates.
10013 \*(UA currently offers no mechanism to fetch CRLs, nor to access them on
10014 the Internet, so you have to retrieve them by some external mechanism.
10017 \*(UA accepts CRLs in PEM format only;
10018 CRLs in DER format must be converted, like, e.\|g.:
10021 .Dl $ openssl crl \-inform DER \-in crl.der \-out crl.pem
10024 To tell \*(UA about the CRLs, a directory that contains all CRL files
10025 (and no other files) must be created.
10030 variables, respectively, must then be set to point to that directory.
10031 After that, \*(UA requires a CRL to be present for each CA that is used
10032 to verify a certificate.
10035 .\" .Ss "Handling spam" {{{
10036 .Ss "Handling spam"
10038 \*(OP \*(UA can make use of several spam interfaces for the purpose of
10039 identification of, and, in general, dealing with spam messages.
10040 A precondition of most commands in order to function is that the
10042 variable is set to one of the supported interfaces.
10043 Once messages have been identified as spam their (volatile)
10045 state can be prompted: the
10049 message specifications will address respective messages and their
10051 entries will be used when displaying the
10053 in the header display.
10058 rates the given messages and sets their
10061 If the spam interface offers spam scores those can also be displayed in
10062 the header display by including the
10072 will interact with the Bayesian filter of the chosen interface and learn
10073 the given messages as
10077 respectively; the last command can be used to cause
10079 of messages; it adheres to their current
10081 state and thus reverts previous teachings.
10086 will simply set and clear, respectively, the mentioned volatile
10088 message flag, without any interface interaction.
10097 requires a running instance of the
10099 server in order to function, started with the option
10101 shall Bayesian filter learning be possible.
10103 .Bd -literal -offset indent
10104 $ spamd -i localhost:2142 -i /tmp/.spamsock -d [-L] [-l]
10105 $ spamd --listen=localhost:2142 --listen=/tmp/.spamsock \e
10106 --daemonize [--local] [--allow-tell]
10110 Thereafter \*(UA can make use of these interfaces:
10112 .Bd -literal -offset indent
10113 $ \*(uA -Sspam-interface=spamc -Sspam-maxsize=500000 \e
10114 -Sspamc-command=/usr/local/bin/spamc \e
10115 -Sspamc-arguments="-U /tmp/.spamsock" -Sspamc-user=
10117 $ \*(uA -Sspam-interface=spamc -Sspam-maxsize=500000 \e
10118 -Sspamc-command=/usr/local/bin/spamc \e
10119 -Sspamc-arguments="-d localhost -p 2142" -Sspamc-user=
10123 Using the generic filter approach allows usage of programs like
10125 Here is an example, requiring it to be accessible via
10128 .Bd -literal -offset indent
10129 $ \*(uA -Sspam-interface=filter -Sspam-maxsize=500000 \e
10130 -Sspamfilter-ham="bogofilter -n" \e
10131 -Sspamfilter-noham="bogofilter -N" \e
10132 -Sspamfilter-nospam="bogofilter -S" \e
10133 -Sspamfilter-rate="bogofilter -TTu 2>/dev/null" \e
10134 -Sspamfilter-spam="bogofilter -s" \e
10135 -Sspamfilter-rate-scanscore="1;^(.+)$"
10139 Because messages must exist on local storage in order to be scored (or
10140 used for Bayesian filter training), it is possibly a good idea to
10141 perform the local spam check last:
10143 .Bd -literal -offset indent
10144 define spamdelhook {
10146 spamset (header x-dcc-brand-metrics "bulk")
10147 # Server-side spamassassin(1)
10148 spamset (header x-spam-flag "YES")
10149 del :s # TODO we HAVE to be able to do `spamrate :u ! :sS'
10150 move :S +maybe-spam
10153 move :S +maybe-spam
10155 set folder-hook-FOLDER=spamdelhook
10159 See also the documentation for the variables
10160 .Va spam-interface , spam-maxsize ,
10161 .Va spamc-command , spamc-arguments , spamc-user ,
10162 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
10165 .Va spamfilter-rate-scanscore .
10173 In general it is a good idea to turn on
10179 twice) if something doesn't work well.
10180 Very often a diagnostic message can be produced that leads to the
10181 problems' solution.
10183 .\" .Ss "\*(UA shortly hangs on startup" {{{
10184 .Ss "\*(UA shortly hangs on startup"
10186 This can have two reasons, one is the necessity to wait for a file lock
10187 and can't be helped, the other being that \*(UA calls the function
10189 in order to query the nodename of the box (sometimes the real one is
10190 needed instead of the one represented by the internal variable
10192 You may have varying success by ensuring that the real hostname and
10196 or, more generally, that the name service is properly setup \(en
10199 return what you'd expect?
10200 Does this local hostname has a domain suffix?
10201 RFC 6762 standardized the link-local top-level domain
10205 .\" .Ss "I can't login to Google mail aka GMail" {{{
10206 .Ss "I can't login to Google mail aka GMail"
10208 Since 2014 some free service providers classify programs as
10210 unless they use a special authentification method (OAuth 2.0) which
10211 wasn't standardized for non-HTTP protocol authentication token query
10212 until August 2015 (RFC 7628).
10215 Different to Kerberos / GSSAPI, which is developed since the mid of the
10216 1980s, where a user can easily create a local authentication ticket for
10217 her- and himself with the locally installed
10219 program, that protocol has no such local part but instead requires
10220 a world-wide-web query to create or fetch a token; since there is no
10221 local cache this query has to be performed whenever \*(UA is invoked
10222 from the command line (in interactive sessions situation may differ).
10225 \*(UA doesn't support OAuth.
10226 Because of this it is necessary to declare \*(UA a
10227 .Dq less secure app
10228 (on the providers account web page) in order to read and send mail.
10229 However, it also seems possible to take the following steps instead:
10234 give the provider the number of a mobile phone,
10237 .Dq 2-Step Verification ,
10239 create an application specific password (16 characters), and
10241 use that special password instead of your real Google account password in
10242 \*(UA (for more on that see the section
10243 .Sx "On URL syntax and credential lookup" ) .
10247 .\" .Ss "Not \(dqdefunctional\(dq, but the editor key won't work" {{{
10248 .Ss "Not \(dqdefunctional\(dq, but the editor key won't work"
10250 It can happen that the terminal library (see
10251 .Sx "On terminal control and line editor",
10254 reports different codes than the terminal really sends, in which case
10255 \*(UA will tell that a key binding is functional, but won't be able to
10256 recognize it because the received data doesn't match anything expected.
10257 The verbose listing of
10259 ings will show the byte sequences that are expected.
10262 To overcome the situation, use, e.g., the program
10264 in conjunction with the
10266 flag if available, to see the byte sequences which are actually produced
10267 by keypresses, and use the variable
10269 to make \*(UA aware of them.
10270 E.g., the terminal this is typed on produces some false sequences, here
10271 an example showing the shifted home key:
10273 .Bd -literal -offset indent
10276 # 1B 5B=[ 31=1 3B=; 32=2 48=H
10281 ? \*(uA -v -Stermcap='kHOM=\eE[H'
10290 .\" .Sh "SEE ALSO" {{{
10300 .Xr spamassassin 1 ,
10309 .Xr mailwrapper 8 ,
10314 .\" .Sh HISTORY {{{
10317 M. Douglas McIlroy writes in his article
10318 .Dq A Research UNIX Reader: Annotated Excerpts \
10319 from the Programmer's Manual, 1971-1986
10322 command already appeared in First Edition
10326 .Bd -ragged -offset indent
10327 Electronic mail was there from the start.
10328 Never satisfied with its exact behavior, everybody touched it at one
10329 time or another: to assure the safety of simultaneous access, to improve
10330 privacy, to survive crashes, to exploit uucp, to screen out foreign
10331 freeloaders, or whatever.
10332 Not until v7 did the interface change (Thompson).
10333 Later, as mail became global in its reach, Dave Presotto took charge and
10334 brought order to communications with a grab-bag of external networks
10340 Mail was written in 1978 by Kurt Shoens and developed as part of the
10343 distribution until 1995.
10344 Mail has then seen further development in open source
10346 variants, noticeably by Christos Zoulas in
10348 Basing upon this Nail, later Heirloom Mailx, was developed by Gunnar
10349 Ritter in the years 2000 until 2008.
10350 Since 2012 S-nail is maintained by Steffen (Daode) Nurpmeso.
10351 This man page is derived from
10352 .Dq The Mail Reference Manual
10353 that was originally written by Kurt Shoens.
10359 .An "Kurt Shoens" ,
10360 .An "Edward Wang" ,
10361 .An "Keith Bostic" ,
10362 .An "Christos Zoulas" ,
10363 .An "Gunnar Ritter" ,
10364 .An "Steffen Nurpmeso" Aq Mt s-nail-users@lists.sourceforge.net
10366 .Mt s-mailx@sdaoden.eu ) .
10369 .\" .Sh CAVEATS {{{
10372 \*(ID Interrupting an operation via
10376 is often problematic: many library functions cannot deal with the
10378 that this software (still) performs.
10381 The SMTP and POP3 protocol support of \*(UA is very basic.
10382 Also, if it fails to contact its upstream SMTP server, it will not make
10383 further attempts to transfer the message at a later time (setting
10388 If this is a concern, it might be better to set up a local SMTP server
10389 that is capable of message queuing.
10395 After deleting some message of a POP3 mailbox the header summary falsely
10396 claims that there are no messages to display, you need to perform
10397 a scroll or dot movement to restore proper state.
10399 In threaded display a power user may encounter crashes very
10400 occasionally (this is may and very).
10404 in the source repository lists future directions.