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
577 is enabled in compose mode.
578 The following prepares an email message in a batched dry run:
579 .Bd -literal -offset indent
580 $ LC_ALL=C printf 'm bob\en~s ubject\enText\en~.\enx\en' | \e
581 LC_ALL=C \*(uA -:/ -d# -X'alias bob bob@exam.ple'
586 This flag forces termination of option processing in order to prevent
589 It also forcefully puts \*(UA into send mode, see
590 .Sx "On sending mail, and non-interactive mode" .
594 In the above list of supported command line options,
598 are implemented by means of
600 ting the respective option, as via
603 .Op Ar mta-option ...
605 arguments that are given at the end of the command line after a
607 separator will be passed through to a file-based
609 (Mail-Transfer-Agent) and persist for an entire (interactive) session
610 \(en if the setting of
612 allows their recognition; no such constraints apply to the variable
616 .\" .Ss "A starter" {{{
619 \*(UA is a direct descendant of
621 Mail, a successor of the Research
624 .Dq was there from the start
629 Mail reference manual begins with the following words:
631 .Bd -ragged -offset indent
632 Mail provides a simple and friendly environment for sending and
634 It divides incoming mail into its constituent messages and allows the
635 user to deal with them in any order.
636 In addition, it provides a set of
638 -like commands for manipulating messages and sending mail.
639 Mail offers the user simple editing capabilities to ease the composition
640 of outgoing messages, as well as providing the ability to define and
641 send to names which address groups of users.
645 \*(UA is thus the user side of the
647 mail system, whereas the system side (Mail-Transfer-Agent, MTA) was
648 traditionally taken by
650 and most MTAs provide a binary of this name for compatibility purposes.
655 of \*(UA then the system side is not a mandatory precondition for mail
659 Because \*(UA strives for compliance with POSIX
661 it is likely that some configuration settings have to be adjusted before
662 using it is a smooth experience.
665 file already bends those standard imposed settings a bit towards more
666 user friendliness and safety, e.g., it
668 s the internal variables
672 in order to suppress the automatic moving of messages to
674 that would otherwise occur (see
675 .Sx "Message states" )
678 to not remove empty files in order not to mangle file permissions when
679 files eventually get recreated (\*(UA actively manages the file mode
682 upon program startup).
686 .Sx "INTERNAL VARIABLES" ,
687 isn't set by default so that file grouping (via the
689 prefix as documented for
691 is not functional by default.
694 contains some suggestions.
697 .\" .Ss "On sending mail, and non-interactive mode" {{{
698 .Ss "On sending mail, and non-interactive mode"
700 To send a message to one or more people, using a local or a builtin
702 (Mail-Transfer-Agent) transport to actually deliver the generated mail
703 message, \*(UA can be invoked with arguments which are the names of
704 people to whom the mail will be sent, and the command line options
708 can be used to add (blind) carbon copy receivers:
710 .Bd -literal -offset indent
711 $ \*(uA -s ubject -a ttach.txt bill@exam.ple
712 # But... try it in an isolated dry-run mode first
713 $ LC_ALL=C \*(uA -:/ -d -vv -Ssendwait \e
714 -b bcc@exam.ple -c cc@exam.ple -. \e
715 '(Lovely) Bob <bob@exam.ple>' eric@exam.ple
717 $ LC_ALL=C \*(uA -:/ -d -vv -Sv15-compat -Ssendwait \e
718 -S 'mta=smtps://mylogin@exam.ple:465' -Ssmtp-auth=login \e
719 -S 'from=scriptreply@exam.ple' \e
725 If standard input is a terminal rather than the message to be sent,
726 the user is expected to type in the message contents.
727 In this compose mode \*(UA treats lines beginning with the character
729 special \(en these are so-called
731 which can be used to read in files, process shell commands, add and edit
732 attachments and more; e.g., the tilde escape
734 will start the text editor to revise the message in it's current state,
736 allows editing of the most important message headers and
738 gives an overview of available tilde escapes.
742 at the beginning of an empty line leaves compose mode and causes the
743 message to be sent, whereas typing
746 twice will abort the current letter (saving its contents in the file
752 Messages are sent asynchronously, without supervision, unless the variable
754 is set, therefore send errors are not recognizable until then.
760 .Sx "INTERNAL VARIABLES"
761 can be used to alter default behavior; e.g.,
766 will automatically startup a text editor when compose mode is entered,
768 will cause the user to be prompted actively for carbon-copy recipients
771 option will allow leaving compose mode by writing a line consisting
777 hook macros may be set to automatically adjust some settings dependent
778 on receiver, sender or subject contexts.
781 Especially for using public mail provider accounts with the SMTP
783 it is often necessary to set
785 and saving a copy of sent messages in a
787 may be desirable \(en as for most mailbox file targets some special
788 syntax conventions are recognized (see the
790 command for more on that).
793 for the purpose of arranging a complete environment of settings that can
794 be switched to with a single command or command line option may be
797 contains example configurations for sending messages via some of the
798 well-known public mail providers and also gives a compact overview on
799 how to setup a secure SSL/TLS environment).
804 sandbox dry-run tests first will prove correctness.
808 .Sx "On URL syntax and credential lookup"
809 will spread light on the different ways of how to specify user email
810 account credentials, the
812 variable chains, and accessing protocol-specific resources,
815 goes into the details of character encoding and how to use them for
816 representing messages and MIME part contents by specifying them in
818 and reading the section
819 .Sx "The mime.types files"
820 should help to understand how the MIME-type of outgoing attachments are
821 classified, and what can be done for fine-tuning.
824 Message recipients (as specified on the command line or defined in
829 may not only be email addressees but can also be names of mailboxes and
830 even complete shell command pipe specifications.
833 is not set then only network addresses (see
835 for a description of mail addresses) and plain user names (including MTA
836 aliases) may be used, other types will be filtered out, giving a warning
839 .\" When changing any of the following adjust any RECIPIENTADDRSPEC;
840 .\" grep the latter for the complete picture
844 is set then extended recipient addresses will optionally be accepted:
845 Any name which starts with a vertical bar
847 character specifies a command pipe \(en the command string following the
849 is executed and the message is sent to its standard input;
850 Likewise, any name that starts with the character solidus
852 or the character sequence dot solidus
854 is treated as a file, regardless of the remaining content.
855 Any other name which contains an at sign
857 character is treated as a network address;
858 Any other name which starts with a plus sign
860 character specifies a mailbox name;
861 Any other name which contains a solidus
863 character but no exclamation mark
867 character before also specifies a mailbox name;
868 What remains is treated as a network address.
870 .Bd -literal -offset indent
871 $ echo bla | \*(uA -Sexpandaddr -s test ./mbox.mbox
872 $ echo bla | \*(uA -Sexpandaddr -s test '|cat >> ./mbox.mbox'
873 $ echo safe | LC_ALL=C \e
874 \*(uA -:/ -Sv15-compat -Ssendwait -Snosave \e
875 -Sexpandaddr=fail,-all,+addr -s test \e
880 It is possible to create personal distribution lists via the
882 command, so that, for instance, the user can send mail to
884 and have it go to a group of people.
885 These aliases have nothing in common with the system wide aliases that
886 may be used by the MTA, which are subject to the
890 and are often tracked in a file
896 Personal aliases will be expanded by \*(UA before the message is sent,
897 and are thus a convenient alternative to specifying each addressee by
901 .Dl alias cohorts bill jkf mark kridle@ucbcory ~/mail/cohorts.mbox
904 To avoid environmental noise scripts should
906 \*(UA from any configuration files and create a script-local
907 environment, ideally with the command line options
909 to disable any configuration file in conjunction with repetitions of
911 to specify variables:
913 .Bd -literal -offset indent
914 $ env LC_ALL=C \*(uA -:/ \e
915 -Sv15-compat -Ssendwait -Snosave -Sttycharset=utf-8 \e
916 -Sexpandaddr=fail,-all,+addr \e
917 -S 'mta=smtps://mylogin@exam.ple:465' -Ssmtp-auth=login \e
918 -S 'from=scriptreply@exam.ple' \e
919 -s 'subject' -a attachment_file \e
920 -. "Recipient 1 <rec1@exam.ple>" rec2@exam.ple \e
925 As shown, scripts can
927 a locale environment, the above specifies the all-compatible 7-bit clean
930 but will nonetheless take and send UTF-8 in the message text by using
932 In interactive mode, which is introduced in the next section, messages
933 can be sent by calling the
935 command with a list of recipient addresses \(em the semantics are
936 completely identical to non-interactive message sending:
938 .Bd -literal -offset indent
939 $ \*(uA -d -Squiet -Semptystart
940 "/var/spool/mail/user": 0 messages
941 ? mail "Recipient 1 <rec1@exam.ple>", rec2@exam.ple
942 ? # Will do the right thing (tm)
943 ? m rec1@exam.ple rec2@exam.ple
947 .\" .Ss "On reading mail, and interactive mode" {{{
948 .Ss "On reading mail, and interactive mode"
950 When invoked without addressees \*(UA enters interactive mode in which
952 When used like that the user's system
956 for an in-depth description of the different mailbox types that exist)
957 is read in and a one line header of each message therein is displayed.
958 The visual style of this summary of
960 can be adjusted through the variable
962 and the possible sorting criterion via
964 If the initially opened mailbox is empty \*(UA will instead exit
965 immediately (after displaying a message) unless the variable
974 will give a listing of all available commands and
976 will give a summary of some common ones.
977 If the \*(OPal documentation strings are available one can type
979 and see the actual expansion of
981 and what it's purpose is, i.e., commands can be abbreviated
982 (note that POSIX defines some abbreviations, so that the alphabetical
983 order of commands doesn't necessarily relate to the abbreviations; it is
984 possible to define overwrites with the
989 Messages are given numbers (starting at 1) which uniquely identify
990 messages; the current message \(en the
992 \(en will either be the first new message, or the first unread message,
993 or the first message of the mailbox; the option
995 will instead cause usage of the last message for this purpose.
1000 ful of header summaries containing the
1004 will display only the summaries of the given messages, defaulting to the
1008 Message content can be displayed on the users' terminal with the
1012 If instead the command
1014 is used, only the first
1016 of a message will be shown.
1017 By default the current message
1019 is displayed, but like with many other commands it is possible to give
1020 a fancy message specification (see
1021 .Sx "Specifying messages" ) ,
1024 will display all unread messages,
1029 will type the messages 1 and 5,
1031 will type the messages 1 through 5, and
1035 will display the last and the next message, respectively.
1038 (a more substantial alias of the standard command
1040 will display a header summary of the given message specification list
1041 instead of their content, e.g., the following will search for subjects:
1044 .Dl from "'@Some subject to search for'"
1047 In the default setup all header fields of a message will be
1049 d, but this can be changed: either by blacklisting a list of fields via
1051 or by whitelisting only a given list with the
1054 .Ql Ic \:retain Ns \0from_ date from to cc subject .
1055 In order to display all header fields of a message regardless of
1056 currently active ignore or retain lists, use the commands
1062 controls whether and when \*(UA will use the configured
1064 for display instead of directly writing to the user terminal
1066 (generally speaking).
1067 Note that historically the global
1069 not only adjusts the list of displayed headers, but also sets
1073 Dependent upon the configuration a line editor (see the section
1074 .Sx "On terminal control and line editor" )
1075 aims at making user experience with the many
1078 When reading the system
1084 specified a mailbox explicitly prefixed with the special
1086 modifier (propagating the mailbox to a primary one) then messages which
1087 have been read will be moved to a secondary mailbox, the user's
1089 file, automatically when the mailbox is left, either by changing the
1090 active mailbox or by quitting \*(UA (also see
1091 .Sx "Message states" )
1092 \(en this automatic moving from a system or primary to the secondary
1093 mailbox is not performed when the variable
1098 After examining a message the user can also
1102 to the sender and all recipients or
1104 exclusively to the sender(s).
1105 Messages can also be
1107 ed (shorter alias is
1109 Note that when replying to or forwarding a message recipient addresses
1110 will be stripped from comments and names unless the option
1113 Deletion causes \*(UA to forget about the message;
1114 This is not irreversible, though, one can
1116 the message by giving its number,
1117 or the \*(UA session can be ended by giving the
1122 To end a mail processing session one may either issue
1124 to cause a full program exit, which possibly includes
1125 automatic moving of read messages to
1127 as well as updating the \*(OPal line editor
1131 instead in order to prevent any of these actions.
1134 .\" .Ss "HTML mail and MIME attachments" {{{
1135 .Ss "HTML mail and MIME attachments"
1137 Messages which are HTML-only get more and more common and of course many
1138 messages come bundled with a bouquet of MIME attachments.
1139 Whereas \*(UA \*(OPally supports a simple HTML-to-text converter to deal
1140 with HTML messages (see
1141 .Sx "The mime.types files" ) ,
1142 it normally can't deal with any of these itself, but instead programs
1143 need to become registered to deal with specific MIME types or file
1145 These programs may either prepare plain text versions of their input
1146 in order to enable \*(UA to display the content on the terminal,
1147 or display the content themselves, for example in a graphical window.
1150 To install an external handler program for a specific MIME type set an
1152 .Va pipe-TYPE/SUBTYPE
1153 variable; to instead define a handler for a specific file extension set
1156 variable \(en these handlers take precedence.
1157 \*(OPally \*(UA supports mail user agent configuration as defined in
1158 RFC 1524; this mechanism, documented in the section
1159 .Sx "The Mailcap files" ,
1160 will be queried for display or quote handlers if none of the former two
1161 .\" TODO v15-compat "will be" -> "is"
1162 did; it will be the sole source for handlers of other purpose.
1163 A last source for handlers may be the MIME type definition itself, if
1164 the \*(UA specific type-marker extension was used when defining the type
1167 (Many of the builtin MIME types do so by default.)
1171 .Va mime-counter-evidence
1172 can be set to improve dealing with faulty MIME part declarations as are
1173 often seen in real-life messages.
1174 E.g., to display a HTML message inline (that is, converted to a more
1175 fancy plain text representation than the builtin converter is capable to
1176 produce) with either of the text-mode browsers
1180 teach \*(UA about MathML documents and make it display them as plain
1181 text, and to open PDF attachments in an external PDF viewer,
1182 asynchronously and with some other magic attached:
1184 .Bd -literal -offset indent
1185 if $features !@ +filter-html-tagsoup
1186 #set pipe-text/html='elinks -force-html -dump 1'
1187 set pipe-text/html='lynx -stdin -dump -force_html'
1188 # Display HTML as plain text instead
1189 #set pipe-text/html=@
1191 mimetype '@ application/mathml+xml mathml'
1192 wysh set pipe-application/pdf='@&=@ \e
1193 trap "rm -f \e"${NAIL_FILENAME_TEMPORARY}\e"" EXIT;\e
1194 trap "trap \e"\e" INT QUIT TERM; exit 1" INT QUIT TERM;\e
1195 mupdf "${NAIL_FILENAME_TEMPORARY}"'
1199 Note: special care must be taken when using such commands as mail
1200 viruses may be distributed by this method: if messages of type
1201 .Ql application/x-sh
1202 or files with the extension
1204 were blindly filtered through the shell, for example, a message sender
1205 could easily execute arbitrary code on the system \*(UA is running on.
1206 For more on MIME, also in respect to sending of messages, see the
1208 .Sx "The mime.types files" ,
1209 .Sx "The Mailcap files"
1214 .\" .Ss "Mailing lists" {{{
1217 \*(UA offers some support to ease handling of mailing lists.
1220 promotes all given arguments to known mailing lists, and
1222 sets their subscription attribute, creating them first as necessary.
1227 automatically, but only resets the subscription attribute.)
1228 Using the commands without arguments will show (a subset of) all
1229 currently defined mailing lists.
1234 can be used to mark out messages with configured list addresses
1235 in the header display.
1238 \*(OPally mailing lists may also be specified as (extended) regular
1239 expressions, which allows matching of many addresses with a single
1241 However, all fully qualified list addresses are matched via a fast
1242 dictionary, whereas expressions are placed in (a) list(s) which is
1243 (are) matched sequentially.
1245 .Bd -literal -offset indent
1246 set followup-to followup-to-honour=ask-yes reply-to-honour=ask-yes
1247 wysh mlist a1@b1.c1 a2@b2.c2 '.*@lists\e.c3$'
1248 mlsubscribe a4@b4.c4 exact@lists.c3
1253 .Va followup-to-honour
1255 .Ql Mail-\:Followup-\:To:
1256 header is honoured when the message is being replied to (via
1262 controls whether this header is created when sending mails; it will be
1263 created automatically for a couple of reasons, too, like when the
1265 .Dq mailing list specific
1270 is used to respond to a message with its
1271 .Ql Mail-Followup-To:
1275 A difference in between the handling of known and subscribed lists is
1276 that the address of the sender is usually not part of a generated
1277 .Ql Mail-Followup-To:
1278 when addressing the latter, whereas it is for the former kind of lists.
1279 Usually because there are exceptions: say, if multiple lists are
1280 addressed and not all of them are subscribed lists.
1282 For convenience \*(UA will, temporarily, automatically add a list
1283 address that is presented in the
1285 header of a message that is being responded to to the list of known
1287 Shall that header have existed \*(UA will instead, dependent on the
1289 .Va reply-to-honour ,
1292 for this purpose in order to accept a list administrators' wish that
1293 is supposed to have been manifested like that (but only if it provides
1294 a single address which resides on the same domain as what is stated in
1298 .\" .Ss "Resource files" {{{
1299 .Ss "Resource files"
1301 Upon startup \*(UA reads in several resource files:
1303 .Bl -tag -width ".It Pa _AIL_EXTRA_R_"
1306 System wide initialization file.
1307 Reading of this file can be suppressed, either by using the
1311 command line options, or by setting the
1314 .Ev NAIL_NO_SYSTEM_RC .
1318 File giving initial commands.
1319 A different file can be chosen by setting the
1323 Reading of this file can be suppressed with the
1325 command line option.
1327 .It Va NAIL_EXTRA_RC
1328 Can be used to define an optional startup file to be read after all
1329 other resource files.
1330 It can be used to specify settings that are not understood by other
1332 implementations, for example.
1333 This variable is only honoured when defined in a resource file, e.g.,
1335 .Sx "INTERNAL VARIABLES" .
1339 The content of these files is interpreted as follows:
1342 .Bl -bullet -compact
1344 A lines' leading whitespace is removed.
1346 Empty lines are ignored.
1348 Any other line is interpreted as a command.
1349 It may be spread over multiple input lines if the newline character is
1351 by placing a reverse solidus character
1353 as the last character of the line; whereas any leading whitespace of
1354 follow lines is ignored, trailing whitespace before a escaped newline
1355 remains in the input.
1357 If the line (content) starts with the number sign
1359 then it is a comment-command \(en a real command! \(en and also ignored.
1360 This command is the only form of comment that is understood.
1364 Unless \*(UA is about to enter interactive mode syntax errors that occur
1365 while loading these files are treated as errors and cause program exit.
1366 More files with syntactically equal content can be
1368 The following, saved in a file, would be an examplary content:
1370 .Bd -literal -offset indent
1371 # This line is a comment command. And y\e
1372 es, it is really continued here.
1379 .\" .Ss "Character sets" {{{
1380 .Ss "Character sets"
1382 \*(OP \*(UA detects the character set of the terminal by using
1383 mechanisms that are controlled by the
1388 should give an overview); the \*(UA internal variable
1390 will be set to the detected terminal character set accordingly
1391 and will thus show up in the output of the commands
1397 However, a user supplied
1399 value is not overwritten by this detection mechanism: this
1401 must be used if the detection doesn't work properly,
1402 and it may be used to adjust the name of the locale character set.
1403 E.g., on BSD systems one may use a locale with the character set
1404 ISO8859-1, which is not a valid name for this character set; to be on
1405 the safe side, one may set
1407 to the correct name, which is ISO-8859-1.
1410 Note that changing the value doesn't mean much beside that,
1411 since several aspects of the real character set are implied by the
1412 locale environment of the system,
1413 and that stays unaffected by the content of an overwritten
1416 (This is mostly an issue when interactively using \*(UA, though.
1417 It is actually possible to send mail in a completely
1419 locale environment, an option that \*(UA's test-suite uses excessively.)
1422 If no character set conversion capabilities have been compiled into
1425 doesn't include the term
1429 will be the only supported character set,
1430 it is simply assumed that it can be used to exchange 8-bit messages,
1431 and the rest of this section does not apply;
1432 it may however still be necessary to explicitly set it if automatic
1433 detection fails, since in that case it defaults to the mentioned
1434 .\" (Keep in SYNC: ./nail.1:"Character sets", ./nail.h:CHARSET_*!)
1438 When reading messages, their text is converted into
1440 as necessary in order to display them on the users terminal.
1441 Unprintable characters and invalid byte sequences are detected
1442 and replaced by proper substitution characters (unless the variable
1444 was set once \*(UA was started).
1446 .Va charset-unknown-8bit
1447 to deal with another hairy aspect of message interpretation.
1450 When sending messages all their parts and attachments are classified.
1451 Whereas no character set conversion is performed on those parts which
1452 appear to be binary data,
1453 the character set being used must be declared within the MIME header of
1454 an outgoing text part if it contains characters that do not conform to
1455 the set of characters that are allowed by the email standards.
1456 Permissible values for character sets can be declared using the
1460 which defines a catch-all last-resort fallback character set that is
1461 implicitly appended to the list of character-sets in
1465 When replying to a message and the variable
1466 .Va reply-in-same-charset
1467 is set then the character set of the message being replied to is tried
1469 And it is also possible to make \*(UA work even more closely related to
1470 the current locale setting automatically by using the variable
1471 .Va sendcharsets-else-ttycharset ,
1472 please see there for more information.
1475 All the specified character sets are tried in order unless the
1476 conversion of the part or attachment succeeds.
1477 If none of the tried (8-bit) character sets is capable to represent the
1478 content of the part or attachment,
1479 then the message will not be sent and its text will optionally be
1483 In general, if the message
1484 .Dq Cannot convert from a to b
1485 appears, either some characters are not appropriate for the currently
1486 selected (terminal) character set,
1487 or the needed conversion is not supported by the system.
1488 In the first case, it is necessary to set an appropriate
1490 locale and/or the variable
1494 The best results are usually achieved when \*(UA is run in a UTF-8
1495 locale on a UTF-8 capable terminal, in which case the full Unicode
1496 spectrum of characters is available.
1497 In this setup characters from various countries can be displayed,
1498 while it is still possible to use more simple character sets for sending
1499 to retain maximum compatibility with older mail clients.
1502 On the other hand the POSIX standard defines a locale-independent 7-bit
1503 .Dq portable character set
1504 that should be used when overall portability is an issue, the even more
1505 restricted subset named
1506 .Dq portable filename character set
1507 consisting of A-Z, a-z, 0-9, period
1516 .\" .Ss "Message states" {{{
1517 .Ss "Message states"
1519 \*(UA differentiates in between several different message states;
1520 the current state will be reflected in header summary displays if
1522 is configured to do so (via the internal variable
1524 and messages can also be selected and be acted upon depending on their
1526 .Sx "Specifying messages" ) .
1527 When operating on the system
1529 box or in primary mailboxes opened with the special prefix
1533 special actions, like the automatic moving of messages to the secondary
1535 mailbox may be applied when the mailbox is left (also implicitly via
1536 a successful exit of \*(UA, but not if the special command
1538 is used) \(en however, because this may be irritating to users which
1541 mail-user-agents, the default global
1547 variables in order to suppress this behaviour.
1549 .Bl -tag -width ".It Ql _reserved"
1551 Message has neither been viewed nor moved to any other state.
1552 Such messages are retained even in the primary system mailbox.
1555 Message has neither been viewed nor moved to any other state, but the
1556 message was present already when the mailbox has been opened last:
1557 Such messages are retained even in the primary system mailbox.
1560 The message has been processed by one of the following commands:
1580 commands may also cause the next message to be marked as read, depending
1586 command is used, messages that are in the primary system mailbox or in
1587 mailboxes which were opened with the special
1591 state when the mailbox is left will be saved in
1598 The message has been processed by one of the following commands:
1604 can be used to access such messages.
1607 The message has been processed by a
1609 command and it will be retained in its current location.
1612 The message has been processed by one of the following commands:
1618 command is used, messages that are in the primary system mailbox or in
1619 mailboxes which were opened with the special
1623 state when the mailbox is left will be deleted; they will be saved in
1631 .\" .Ss "Specifying messages" {{{
1632 .Ss "Specifying messages"
1639 can be given a list of message numbers as arguments to apply to a number
1640 of messages at once.
1643 deletes messages 1 and 2,
1646 will delete the messages 1 through 5.
1647 In sorted or threaded mode (see the
1651 will delete the messages that are located between (and including)
1652 messages 1 through 5 in the sorted/threaded order, as shown in the
1655 Multiple colon modifiers can be joined into one, e.g.,
1657 The following special message names exist:
1659 .Bl -tag -width ".It Ar _n_u"
1665 All old messages (any not in state
1690 All answered messages
1695 All messages marked as draft.
1697 \*(OP All messages classified as spam.
1699 \*(OP All messages with unsure spam classification.
1701 The current message, the so-called
1704 The message that was previously the current message.
1706 The parent message of the current message,
1707 that is the message with the Message-ID given in the
1709 field or the last entry of the
1711 field of the current message.
1713 The next previous undeleted message,
1714 or the next previous deleted message for the
1717 In sorted/threaded mode,
1718 the next previous such message in the sorted/threaded order.
1720 The next undeleted message,
1721 or the next deleted message for the
1724 In sorted/threaded mode,
1725 the next such message in the sorted/threaded order.
1727 The first undeleted message,
1728 or the first deleted message for the
1731 In sorted/threaded mode,
1732 the first such message in the sorted/threaded order.
1735 In sorted/threaded mode,
1736 the last message in the sorted/threaded order.
1740 selects the message addressed with
1744 is any other message specification,
1745 and all messages from the thread that begins at it.
1746 Otherwise it is identical to
1751 the thread beginning with the current message is selected.
1756 All messages that were included in the message list for the previous
1759 .It Ar / Ns Ar string
1760 All messages that contain
1762 in the subject field (case ignored).
1769 the string from the previous specification of that type is used again.
1771 .It Xo Op Ar @ Ns Ar name-list Ns
1774 All messages that contain the given case-insensitive search
1776 ession; if the \*(OPal regular expression (see
1778 support is available
1780 will be interpreted as (an extended) one if any of the
1782 (extended) regular expression characters is seen.
1784 .Ar @ Ns Ar name-list
1785 part is missing, the search is restricted to the subject field body,
1788 specifies a comma-separated list of header fields to search, as in
1790 .Dl '@to,from,cc@Someone i ought to know'
1792 In order to search for a string that includes a
1794 (commercial at) character the
1796 is effectively non-optional, but may be given as the empty string.
1797 Some special header fields may be abbreviated:
1811 respectively and case-insensitively.
1816 can be used to search in (all of) the header(s) of the message, and the
1825 can be used to perform full text searches \(en whereas the former
1826 searches only the body, the latter also searches the message header.
1828 This message specification performs full text comparison, but even with
1829 regular expression support it is almost impossible to write a search
1830 expression that savely matches only a specific address domain.
1831 To request that the content of the header is treated as a list of
1832 addresses, and to strip those down to the plain email address which the
1833 search expression is to be matched against, prefix the header name
1834 (abbreviation) with a tilde
1837 .Dl @~f@@a\e.safe\e.domain\e.match$
1841 .Dq any substring matches
1844 header, which will match addresses (too) even if
1846 is set (and POSIX says
1847 .Dq any address as shown in a header summary shall be matchable in this form ) ;
1850 variable is set, only the local part of the address is evaluated
1851 for the comparison, not ignoring case, and the setting of
1853 is completely ignored.
1854 For finer control and match boundaries use the
1856 search expression; the \*(OPal IMAP-style
1858 expression can also be used if substring matches are desired.
1862 \*(OP IMAP-style SEARCH expressions may also be used.
1863 This addressing mode is available with all types of folders;
1864 \*(UA will perform the search locally as necessary.
1865 Strings must be enclosed by double quotes
1867 in their entirety if they contain white space or parentheses;
1868 within the quotes, only reverse solidus
1870 is recognized as an escape character.
1871 All string searches are case-insensitive.
1872 When the description indicates that the
1874 representation of an address field is used,
1875 this means that the search string is checked against both a list
1878 .Bd -literal -offset indent
1879 (\*qname\*q \*qsource\*q \*qlocal-part\*q \*qdomain-part\*q)
1884 and the addresses without real names from the respective header field.
1885 These search expressions can be nested using parentheses, see below for
1889 .Bl -tag -compact -width ".It Ar _n_u"
1890 .It Ar ( criterion )
1891 All messages that satisfy the given
1893 .It Ar ( criterion1 criterion2 ... criterionN )
1894 All messages that satisfy all of the given criteria.
1896 .It Ar ( or criterion1 criterion2 )
1897 All messages that satisfy either
1902 To connect more than two criteria using
1904 specifications have to be nested using additional parentheses,
1906 .Ql (or a (or b c)) ,
1910 .Ql ((a or b) and c) .
1913 operation of independent criteria on the lowest nesting level,
1914 it is possible to achieve similar effects by using three separate
1918 .It Ar ( not criterion )
1919 All messages that do not satisfy
1921 .It Ar ( bcc \*q Ns Ar string Ns Ar \*q )
1922 All messages that contain
1924 in the envelope representation of the
1927 .It Ar ( cc \*q Ns Ar string Ns Ar \*q )
1928 All messages that contain
1930 in the envelope representation of the
1933 .It Ar ( from \*q Ns Ar string Ns Ar \*q )
1934 All messages that contain
1936 in the envelope representation of the
1939 .It Ar ( subject \*q Ns Ar string Ns Ar \*q )
1940 All messages that contain
1945 .It Ar ( to \*q Ns Ar string Ns Ar \*q )
1946 All messages that contain
1948 in the envelope representation of the
1951 .It Ar ( header name \*q Ns Ar string Ns Ar \*q )
1952 All messages that contain
1957 .It Ar ( body \*q Ns Ar string Ns Ar \*q )
1958 All messages that contain
1961 .It Ar ( text \*q Ns Ar string Ns Ar \*q )
1962 All messages that contain
1964 in their header or body.
1965 .It Ar ( larger size )
1966 All messages that are larger than
1969 .It Ar ( smaller size )
1970 All messages that are smaller than
1974 .It Ar ( before date )
1975 All messages that were received before
1977 which must be in the form
1981 denotes the day of the month as one or two digits,
1983 is the name of the month \(en one of
1984 .Ql Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ,
1987 is the year as four digits, e.g.,
1991 All messages that were received on the specified date.
1992 .It Ar ( since date )
1993 All messages that were received since the specified date.
1994 .It Ar ( sentbefore date )
1995 All messages that were sent on the specified date.
1996 .It Ar ( senton date )
1997 All messages that were sent on the specified date.
1998 .It Ar ( sentsince date )
1999 All messages that were sent since the specified date.
2001 The same criterion as for the previous search.
2002 This specification cannot be used as part of another criterion.
2003 If the previous command line contained more than one independent
2004 criterion then the last of those criteria is used.
2008 .\" .Ss "On URL syntax and credential lookup" {{{
2009 .Ss "On URL syntax and credential lookup"
2011 \*(IN For accessing protocol-specific resources usage of Uniform
2012 Resource Locators (URL, RFC 1738) has become omnipresent.
2013 \*(UA expects and understands URLs in the following form;
2016 denote optional parts, optional either because there also exist other
2017 ways to define the information in question or because support of the
2018 part is protocol-specific (e.g.,
2020 is used by the IMAP protocol but not by POP3);
2025 are specified they must be given in URL percent encoded form (RFC 3986;
2033 .Dl PROTOCOL://[USER[:PASSWORD]@]server[:port][/path]
2036 Note that these \*(UA URLs most often don't conform to any real
2037 standard, but instead represent a normalized variant of RFC 1738 \(en
2038 they are not used in data exchange but only meant as a compact,
2039 easy-to-use way of defining and representing information in
2040 a well-known notation.
2043 Many internal variables of \*(UA exist in multiple versions, called
2044 variable chains for the rest of this document: the plain
2049 .Ql variable-USER@HOST .
2056 had been specified in the respective URL, otherwise it refers to the plain
2062 that had been found when doing the user chain lookup as is described
2065 will never be in URL percent encoded form, whether it came from an URL
2066 or not; i.e., values of
2067 .Sx "INTERNAL VARIABLES"
2068 must not be URL percent encoded.
2071 For example, whether an hypothetical URL
2072 .Ql smtp://hey%3Ayou@our.house
2073 had been given that includes a user, or whether the URL was
2074 .Ql smtp://our.house
2075 and the user had been found differently, to lookup the variable chain
2076 .Va smtp-use-starttls
2077 \*(UA first looks for whether
2078 .Ql smtp-\:use-\:starttls-\:hey:you@our.house
2079 is defined, then whether
2080 .Ql smtp-\:use-\:starttls-\:our.house
2081 exists before finally ending up looking at the plain variable itself.
2084 \*(UA obeys the following logic scheme when dealing with the
2085 necessary credential information of an account:
2091 has been given in the URL the variables
2095 are looked up; if no such variable(s) can be found then \*(UA will,
2096 when enforced by the \*(OPal variables
2097 .Va netrc-lookup-HOST
2104 specific entry which provides a
2106 name: this lookup will only succeed if unambiguous (one possible matching
2109 It is possible to load encrypted
2114 If there is still no
2116 then \*(UA will fall back to the user who is supposed to run \*(UA,
2117 the identity of which has been fixated during \*(UA startup and is
2118 known to be a valid user on the current host.
2121 Authentication: unless otherwise noted this will lookup the
2122 .Va PROTOCOL-auth-USER@HOST , PROTOCOL-auth-HOST , PROTOCOL-auth
2123 variable chain, falling back to a protocol-specific default should this
2129 has been given in the URL, then if the
2131 has been found through the \*(OPal
2133 that may have already provided the password, too.
2134 Otherwise the variable chain
2135 .Va password-USER@HOST , password-HOST , password
2136 is looked up and used if existent.
2138 Afterwards the complete \*(OPal variable chain
2139 .Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup
2143 cache is searched for a password only (multiple user accounts for
2144 a single machine may exist as well as a fallback entry without user
2145 but with a password).
2147 If at that point there is still no password available, but the
2148 (protocols') chosen authentication type requires a password, then in
2149 interactive mode the user will be prompted on the terminal.
2154 S/MIME verification works relative to the values found in the
2158 header field(s), which means that the values of
2159 .Va smime-sign , smime-sign-cert , smime-sign-include-certs
2161 .Va smime-sign-message-digest
2162 will not be looked up using the
2166 chains from above but instead use the corresponding values from the
2167 message that is being worked on.
2168 In unusual cases multiple and different
2172 combinations may therefore be involved \(en on the other hand those
2173 unusual cases become possible.
2174 The usual case is as short as:
2177 .Dl set mta=smtp://USER:PASS@HOST smtp-use-starttls \e
2178 .Dl \ \ \ \ smime-sign smime-sign-cert=+smime.pair
2183 contains complete example configurations.
2186 .\" .Ss "On terminal control and line editor" {{{
2187 .Ss "On terminal control and line editor"
2189 \*(OP Terminal control will be realized through one of the standard
2191 libraries, either the
2193 or, alternatively, the
2195 both of which will be initialized to work with the environment variable
2197 Terminal control will enhance or enable interactive usage aspects, e.g.,
2198 .Sx "Coloured display" ,
2199 and extend behaviour of the Mailx-Line-Editor (MLE), which may learn the
2200 byte-sequences of keys like the cursor and function keys, and which will
2201 automatically enter the so-called
2203 alternative screen shall the terminal support it.
2204 The internal variable
2206 can be used to overwrite settings or to learn (correct(ed)) keycodes.
2207 Actual interaction with the chosen library can be disabled completely by
2208 setting the internal variable
2209 .Va termcap-disable ;
2211 will be queried regardless, even if the \*(OPal support for the
2212 libraries has not been enabled at configuration time.
2215 \*(OP The builtin \*(UA Mailx-Line-Editor (MLE) should work in all
2216 environments which comply to the ISO C standard
2218 and will support wide glyphs if possible (the necessary functionality
2219 had been removed from ISO C, but was included in
2221 Prevent usage of a line editor in interactive mode by setting the
2223 .Va line-editor-disable .
2224 Especially if the \*(OPal terminal control support is missing setting
2225 entries in the internal variable
2227 will help shall the MLE misbehave, see there for more.
2228 The MLE can support a little bit of
2234 feature is available then input from line editor prompts will be saved
2235 in a history list that can be searched in and be expanded from.
2236 Such saving can be prevented by prefixing input with any amount of
2238 Aspects of history, like allowed content and maximum size, as well as
2239 whether history shall be saved persistently, can be configured with the
2243 .Va history-gabby-persist
2248 The MLE supports a set of editing and control commands.
2249 By default (as) many (as possible) of these will be assigned to a set of
2250 single-letter control codes, which should work on any terminal.
2253 command is available then the MLE commands can also be accessed freely
2254 by assigning the command name, which is shown in parenthesis in the list
2255 below, to any desired key-sequence, and the MLE will instead and also use
2257 to establish its builtin key bindings
2258 (more of them if the \*(OPal terminal control is available),
2259 an action which can then be suppressed completely by setting
2260 .Va line-editor-no-defaults .
2261 The following uses the
2263 ell-style quote notation that is documented in the introductional
2266 combinations not mentioned either cause job control signals or don't
2267 generate a (unique) keycode:
2271 .Bl -tag -compact -width "Ql _M"
2273 Go to the start of the line
2274 .Pf ( Cd mle-go-home ) .
2277 Move the cursor backward one character
2278 .Pf ( Cd mle-go-bwd ) .
2281 Forward delete the character under the cursor;
2282 quits \*(UA if used on the empty line unless the
2285 .Pf ( Cd mle-del-fwd ) .
2288 Go to the end of the line
2289 .Pf ( Cd mle-go-end ) .
2292 Move the cursor forward one character
2293 .Pf ( Cd mle-go-fwd ) .
2296 Cancel current operation, full reset.
2297 If there is an active history search or tabulator expansion then this
2298 command will first reset that, reverting to the former line content;
2299 thus a second reset is needed for a full reset in this case
2300 .Pf ( Cd mle-reset ) .
2303 Backspace: backward delete one character
2304 .Pf ( Cd mle-del-bwd ) .
2308 Horizontal tabulator:
2309 try to expand the word before the cursor, also supporting \*(UA
2312 .Pf ( Cd mle-complete ) .
2314 .Cd mle-quote-rndtrip .
2318 commit the current line
2319 .Pf ( Cd mle-commit ) .
2322 Cut all characters from the cursor to the end of the line
2323 .Pf ( Cd mle-snarf-end ) .
2327 .Pf ( Cd mle-repaint ) .
2330 \*(OP Go to the next history entry
2331 .Pf ( Cd mle-hist-fwd ) .
2338 \*(OP Go to the previous history entry
2339 .Pf ( Cd mle-hist-bwd ) .
2342 Toggle roundtrip mode shell quotes, where produced,
2344 .Pf ( Cd mle-quote-rndtrip ) .
2345 This setting is temporary, and will be forgotten once the command line
2349 \*(OP Complete the current line from (the remaining) older history entries
2350 .Pf ( Cd mle-hist-srch-bwd ) .
2353 \*(OP Complete the current line from (the remaining) newer history entries
2354 .Pf ( Cd mle-hist-srch-fwd ) .
2357 Paste the snarf buffer
2358 .Pf ( Cd mle-paste ) .
2365 .Pf ( Cd mle-snarf-line ) .
2368 Prompts for a Unicode character (its hexadecimal number) to be inserted
2369 .Pf ( Cd mle-prompt-char ) .
2370 Note this command needs to be assigned to a single-letter control code
2371 in order to become recognized and executed during input of
2372 a key-sequence (only four single-letter control codes can be used for
2373 that shortcut purpose); this control code is special-treated and can't
2374 be part of any other sequence, because any occurrence will perform the
2376 function immediately.
2379 Cut the characters from the one preceding the cursor to the preceding
2381 .Pf ( Cd mle-snarf-word-bwd ) .
2384 Move the cursor forward one word boundary
2385 .Pf ( Cd mle-go-word-fwd ) .
2388 Move the cursor backward one word boundary
2389 .Pf ( Cd mle-go-word-bwd ) .
2392 Escape: reset a possibly used multibyte character input state machine
2393 and \*(OPally a lingering, incomplete key binding
2394 .Pf ( Cd mle-cancel ) .
2395 This command needs to be assigned to a single-letter control code in
2396 order to become recognized and executed during input of a key-sequence
2397 (only four single-letter control codes can be used for that shortcut
2399 This control code may also be part of a multi-byte sequence, but if
2400 a sequence is active and the very control code is currently also an
2401 expected input, then it will first be consumed by the active sequence.
2416 Cut the characters from the one after the cursor to the succeeding word
2418 .Pf ( Cd mle-snarf-word-fwd ) .
2428 this will immediately reset a possibly active search etc.
2432 ring the audible bell.
2436 .\" .Ss "Coloured display" {{{
2437 .Ss "Coloured display"
2439 \*(OP \*(UA can be configured to support a coloured display and font
2440 attributes by emitting ANSI / ISO 6429 SGR (select graphic rendition)
2442 Usage of colours and font attributes solely depends upon the
2443 capability of the detected terminal type that is defined by the
2444 environment variable
2446 and which can be fine-tuned by the user via the internal variable
2450 On top of what \*(UA knows about the terminal the boolean variable
2452 defines whether the actually applicable colour and font attribute
2453 sequences should also be generated when output is going to be paged
2454 through the external program defined by the environment variable
2459 This is not enabled by default because different pager programs need
2460 different command line switches or other configuration in order to
2461 support those sequences.
2462 \*(UA however knows about some widely used pagers and in a clean
2463 environment it is often enough to simply set
2465 please refer to that variable for more on this topic.
2470 is set then any active usage of colour and font attribute sequences
2471 is suppressed, but without affecting possibly established
2476 To define and control colours and font attributes a single multiplexer
2477 command family exists:
2479 shows or defines colour mappings for the given colour type (e.g.,
2482 can be used to remove mappings of a given colour type.
2483 Since colours are only available in interactive mode, it may make
2484 sense to conditionalize the colour setup by encapsulating it with
2487 .Bd -literal -offset indent
2488 if terminal && $features =@ +colour
2489 colour iso view-msginfo ft=bold,fg=green
2490 colour iso view-header ft=bold,fg=red "from,subject"
2491 colour iso view-header fg=red
2493 uncolour iso view-header from,subject
2494 colour iso view-header ft=bold,fg=magenta,bg=cyan
2495 colour 256 view-header ft=bold,fg=208,bg=230 subject,from
2496 colour mono view-header ft=bold
2497 colour mono view-header ft=bold,ft=reverse subject,from
2501 .\" }}} (DESCRIPTION)
2504 .\" .Sh COMMANDS {{{
2507 Each command is typed on a line by itself,
2508 and may take arguments following the command word.
2509 Command names may be abbreviated, in which case the first command that
2510 matches the given prefix will be used.
2513 can be used to show the list of all commands, either alphabetically
2514 sorted or in prefix search order (these don't match, also because the
2515 POSIX standard prescribes a set of abbreviations); a more verbose
2516 listing will be produced if either of
2521 \*(OPally the command
2525 when given an argument, will show a documentation string for the
2526 command matching the expanded argument, as in
2528 which should be a shorthand of
2532 For commands which take message lists as arguments, the next message
2533 forward that satisfies the command's requirements will be used shall no
2534 explicit message list have been specified.
2535 If there are no messages forward of the current message,
2536 the search proceeds backwards,
2537 and if there are no good messages at all,
2538 \*(UA shows an error message and aborts the command.
2539 \*(ID Non-message-list arguments can be quoted using the following methods:
2542 .Bl -bullet -compact -offset indent
2544 An argument can be enclosed between paired double-quotes
2549 any white space, shell word expansion, or reverse solidus characters
2550 (except as described next) within the quotes are treated literally as
2551 part of the argument.
2552 A double-quote will be treated literally within single-quotes and vice
2554 Inside such a quoted string the actually used quote character can be
2555 used nonetheless by escaping it with a reverse solidus
2561 An argument that is not enclosed in quotes, as above, can usually still
2562 contain space characters if those spaces are reverse solidus escaped, as in
2566 A reverse solidus outside of the enclosing quotes is discarded
2567 and the following character is treated literally as part of the argument.
2572 Some commands which don't take message-list arguments can also be
2573 prefixed with the special keyword
2575 to choose \*(INible behaviour, and some new commands support only the
2576 new quoting style (without that keyword) and are flagged \*(NQ.
2577 In the future \*(UA will (mostly) use
2579 compatible argument parsing:
2580 Non-message-list arguments can be quoted using the following shell-style
2581 mechanisms: the escape character, single-quotes, double-quotes and
2582 dollar-single-quotes; any unquoted number sign
2584 starts a comment that ends argument processing.
2585 The overall granularity of error reporting and diagnostics, also
2586 regarding function arguments and their content, will improve.
2590 .Bl -bullet -compact -offset indent
2592 The literal value of any character can be preserved by preceding it
2593 with the escape character reverse solidus
2597 will cause variable expansion of the given name: \*(UA
2598 .Sx "INTERNAL VARIABLES"
2601 (shell) variables can be accessed through this mechanism, brace
2602 enclosing the name is supported.
2605 Arguments which are enclosed in
2606 .Ql 'single-\:quotes'
2607 retain their literal value.
2608 A single-quote cannot occur within single-quotes.
2611 The literal value of all characters enclosed in
2612 .Ql \(dqdouble-\:quotes\(dq
2613 is retained, with the exception of dollar
2615 which will cause variable expansion, as above, backquote (grave accent)
2617 (which not yet means anything special), reverse solidus
2619 which will escape any of the characters dollar
2621 (to prevent variable expansion), backquote (grave accent)
2625 (to prevent ending the quote) and reverse solidus
2627 (to prevent escaping, i.e., to embed a reverse solidus character as-is),
2628 but has no special meaning otherwise.
2631 Arguments enclosed in
2632 .Ql $'dollar-\:single-\:quotes'
2633 extend normal single quotes in that reverse solidus escape sequences are
2634 expanded as follows:
2636 .Bl -tag -compact -width "Ql \eNNN"
2642 an escape character.
2644 an escape character.
2656 emits a reverse solidus character.
2660 double quote (escaping is optional).
2662 eight-bit byte with the octal value
2664 (one to three octal digits), optionally with an additional
2667 A 0 byte will suppress further output for the quoted argument.
2669 eight-bit byte with the hexadecimal value
2671 (one or two hexadecimal characters).
2672 A 0 byte will suppress further output for the quoted argument.
2674 the Unicode / ISO-10646 character with the hexadecimal codepoint value
2676 (one to eight hexadecimal digits) \(em note that Unicode defines the
2677 maximum codepoint to be ever supported as
2682 This escape is only supported in locales which support Unicode (see
2683 .Sx "Character sets" ) ,
2684 in other cases the sequence will remain unexpanded unless the given code
2685 point is ASCII compatible or can be represented in the current locale.
2686 The character NUL will suppress further output for the quoted argument.
2690 except it takes only one to four hexadecimal digits.
2695 This is a mechanism that allows usage of the non-printable (ASCII and
2696 compatible) control codes 0 to 31: to be able to create a printable
2697 representation the numeric value 64 is added to the control code of
2698 desire, and the resulting ASCII character set code point is then
2699 printed, e.g., BEL is
2700 .Ql 7 + 64 = 71 = G .
2701 Often circumflex notation is used for the visualization purpose, e.g,
2703 but the reverse solid notation has been standardized:
2705 The control code NUL
2707 ends argument processing without producing further output.
2709 Non-standard extension: expand the given variable name, as above.
2710 Brace enclosing the name is supported.
2712 Not yet supported, just to raise awareness: Non-standard extension.
2718 .Sy Compatibility notes:
2719 \*(ID Note these are new mechanisms which are not supported by all
2721 Round-tripping (feeding in things shown in list modes again) are not yet
2722 stable or possible at all.
2723 On new-style command lines it is wise to quote semicolon
2727 characters in order to ensure upward compatibility: the author would
2728 like to see things like
2729 .Ql ? echo $'trouble\etahead' | cat >> in_the_shell.txt
2731 .Ql ? top 2 5 10; type 3 22
2733 Before \*(UA will switch entirely to shell-style argument parsing there
2734 will be a transition phase where using
2736 will emit obsoletion warnings.
2737 E.g., the following are equivalent:
2739 .Bd -literal -offset indent
2740 mlist @any\e\e.where\e\e.example\e\e.com
2741 wysh mlist '@any\e.where\e.example\e.com' # This is a comment
2742 wysh mlist $'@any\e\e\ex2Ewhere\e\e.example\e\e\e56com' # A comment
2743 wysh mlist "@any\e.where\e.example\e.com"
2747 In any event an unquoted reverse solidus at the end of a command line is
2748 discarded and the next line continues the command.
2749 \*(ID Note that line continuation is handled before the above parsing is
2750 applied, i.e., the parsers documented above will see merged lines.
2751 Filenames, where expected, are subsequently subjected to the following
2752 transformations, in sequence:
2755 .Bl -bullet -compact -offset indent
2757 If the filename begins with an unquoted plus sign, and the
2759 variable is defined,
2760 the plus sign will be replaced by the value of the
2762 variable followed by a solidus.
2765 variable is unset or is set to null, the filename will be unchanged.
2768 Meta expansions are applied to the filename: a leading tilde
2770 character will be replaced by the expansion of
2772 except when followed by a valid user name, in which case the home
2773 directory of the given user is used instead.
2778 will be replaced by the expansion of the variable, if possible; \*(UA
2779 .Sx "INTERNAL VARIABLES"
2782 (shell) variables can be accessed through this mechanism, and the usual
2783 escape mechanism has to be applied to prevent interpretation.
2784 If the fully expanded filename results in multiple pathnames and the
2785 command is expecting only one file, an error results.
2787 In interactive context, in order to allow simple value acceptance (via
2789 arguments will usually be displayed in a properly quoted form, e.g., a file
2790 .Ql diet\e is \ecurd.txt
2792 .Ql 'diet\e is \ecurd.txt' .
2796 The following commands are available:
2798 .Bl -tag -width ".Ic _ccount"
2805 ) command which follows.
2809 The comment-command causes the entire line to be ignored.
2811 this really is a normal command which' purpose is to discard its
2814 indicating special character, which means that, e.g., trailing comments
2815 on a line are not possible.
2819 Goes to the next message in sequence and types it
2825 Display the preceding message, or the n'th previous message if given
2826 a numeric argument n.
2830 Show the current message number (the
2835 Show a brief summary of commands.
2836 \*(OP Given an argument a synopsis for the command in question is
2837 shown instead; commands can be abbreviated in general and this command
2838 can be used to see the full expansion of an abbreviation including the
2839 synopsis, try, e.g.,
2844 and see how the output changes.
2854 Interprets the remainder of the word as a macro name and passes it
2859 is a shorter synonym for
2860 .Ql call Ar mymacro .
2864 (ac) Creates, selects or lists (an) account(s).
2865 Accounts are special incarnations of
2867 macros and group commands and variable settings which together usually
2868 arrange the environment for the purpose of creating an email account.
2869 Different to normal macros settings which are covered by
2871 \(en here by default enabled! \(en will not be reverted before the
2876 (case-insensitive) always exists, and all but it can be deleted via
2879 Without arguments a listing of all defined accounts is shown.
2880 With one argument the given account is activated: the system
2882 box of that account will be activated (as via
2884 and a possibly installed
2887 The two argument form is identical to defining a macro as via
2889 .Bd -literal -offset indent
2891 set folder=~/mail MAIL=+syste.mbox record=+sent.mbox
2892 set from='myname@myisp.example (My Name)'
2893 set mta=smtp://mylogin@smtp.myisp.example
2899 (a) With no arguments, shows all currently-defined aliases.
2900 With one argument, shows that alias.
2901 With more than one argument,
2902 creates a new alias or appends to an existing one.
2904 can be used to delete aliases.
2908 (alt) Manage a list of alternate addresses / names of the active user,
2909 members of which will be removed from recipient lists when replying to
2912 variable is not set).
2913 If arguments are given the set of alternate names is replaced by them,
2914 without arguments the current set is displayed.
2918 Takes a message list and marks each message as having been answered.
2919 This mark has no technical meaning in the mail system;
2920 it just causes messages to be marked in the header summary,
2921 and makes them specially addressable.
2926 \*(OP\*(NQ The bind command extends the MLE (see
2927 .Sx "On terminal control and line editor" )
2928 with freely configurable key bindings.
2929 With one argument all bindings for the given context are shown,
2930 specifying an asterisk
2932 will show the bindings of all contexts; a more verbose listing will be
2933 produced if either of
2938 With two or more arguments a binding is (re)established:
2939 the first argument is the context to which the binding shall apply,
2940 the second argument is a comma-separated list of the
2942 which form the binding, and any remaining arguments form the expansion.
2943 To indicate that a binding shall not be auto-committed, but that the
2944 expansion shall instead be furtherly editable by the user, an at-sign
2946 (that will be removed) can be placed last in the expansion, from which
2947 leading and trailing whitespace will finally be removed.
2950 Contexts define when a binding applies, i.e., a binding won't be seen
2951 unless the context for which it is defined for is currently active.
2952 This is not true for the binding
2954 which always applies, but which will be searched secondarily to a more
2955 specialized context and may thus have some or all of its key bindings
2956 transparently replaced by equal bindings of more specialized contexts.
2957 The available contexts are
2959 which always applies, and
2961 which applies to compose-mode.
2965 which form the binding are specified as a comma-separated list of
2966 byte-sequences, where each list entry corresponds to one key(press).
2967 \*(OPally a list entry may, indicated by a leading colon character
2969 also refer to the name of a terminal capability;
2970 several dozen names will be compiled into \*(UA and may be specified
2973 or, if existing, by their
2975 name, regardless of the actually used terminal control library.
2976 It is however possible to use any capability, as long as the name is
2977 resolvable by the control library or defined in the internal variable
2979 Input sequences are not case-normalized, so that an exact match is
2980 required to update or remove a binding.
2983 .Bd -literal -offset indent
2984 bind base $'\eE',d mle-snarf-word-fwd # Esc(ape)
2985 bind base $'\eE',$'\ec?' mle-snarf-word-bwd # Esc, Delete
2986 bind compose :kf1 ~e
2987 bind base $'\ecA',:khome,w 'echo An editable binding@'
2988 bind base a,b,c rm -rf / @ # Another editable binding
2992 Note that the entire comma-separated list is first parsed (over) as a
2993 shell-token with whitespace as the field separator, before being parsed
2994 and expanded for real with comma as the field separator, therefore
2995 whitespace needs to be properly quoted:
2996 shell-style quoting is documented in the introductional section of
2998 Using Unicode reverse solidus escape sequences renders a binding
2999 defunctional if the locale doesn't support Unicode (see
3000 .Sx "Character sets" ) ,
3001 and using terminal capabilities does so if no terminal control support
3002 is (currently) available.
3005 The following terminal capability names are builtin and can be used in
3007 or (if available) the two-letter
3009 notation regardless of the actually used library.
3010 See the respective manual for a list of capabilities.
3013 can be used to show all the capabilities of
3015 or the given terminal type;
3018 flag will also show supported (non-standard) extensions.
3021 .Bl -tag -compact -width kcuuf_or_kcuuf
3022 .It Cd kbs Ns \0or Cd kb
3024 .It Cd kdch1 Ns \0or Cd kD
3026 .It Cd kDC Ns \0or Cd *4
3027 \(em shifted variant.
3028 .It Cd kel Ns \0or Cd kE
3029 Clear to end of line.
3030 .It Cd kext Ns \0or Cd @9
3032 .It Cd kich1 Ns \0or Cd kI
3034 .It Cd kIC Ns \0or Cd #3
3035 \(em shifted variant.
3036 .It Cd khome Ns \0or Cd kh
3038 .It Cd kHOM Ns \0or Cd #2
3039 \(em shifted variant.
3040 .It Cd kend Ns \0or Cd @7
3042 .It Cd knp Ns \0or Cd kN
3044 .It Cd kpp Ns \0or Cd kP
3046 .It Cd kcub1 Ns \0or Cd kl
3047 Left cursor (with more modifiers: see below).
3048 .It Cd kLFT Ns \0or Cd #4
3049 \(em shifted variant.
3050 .It Cd kcuf1 Ns \0or Cd kr
3051 Right cursor (ditto).
3052 .It Cd kRIT Ns \0or Cd %i
3053 \(em shifted variant.
3054 .It Cd kcud1 Ns \0or Cd kd
3055 Down cursor (ditto).
3057 \(em shifted variant (only terminfo).
3058 .It Cd kcuu1 Ns \0or Cd ku
3061 \(em shifted variant (only terminfo).
3062 .It Cd kf0 Ns \0or Cd k0
3064 Add one for each function key up to
3069 .It Cd kf10 Ns \0or Cd k;
3071 .It Cd kf11 Ns \0or Cd F1
3073 Add one for each function key up to
3081 Some terminals support key-modifier combination extensions, e.g.,
3083 For example, the delete key,
3085 in its shifted variant, the name is mutated to
3087 then a number is appended for the states
3099 .Ql Shift+Alt+Control
3101 The same for the left cursor key,
3103 .Cd KLFT , KLFT3 , KLFT4 , KLFT5 , KLFT6 , KLFT7 , KLFT8 .
3106 Key bindings can be removed with the command
3108 It is advisable to use an initial escape or other control character (e.g.,
3110 for bindings which describe user key combinations (as opposed to purely
3111 terminal capability based ones), in order to avoid ambiguities whether
3112 input belongs to key sequences or not; it also reduces search time.
3115 may help shall keys and sequences be falsely recognized.
3120 Calls a macro that has been created via
3125 (ch) Change the working directory to
3127 or the given argument.
3133 \*(OP Only applicable to S/MIME signed messages.
3134 Takes a message list and a file name and saves the certificates
3135 contained within the message signatures to the named file in both
3136 human-readable and PEM format.
3137 The certificates can later be used to send encrypted messages to the
3138 respective message senders by setting
3139 .Va smime-encrypt-USER@HOST
3144 (ch) Change the working directory to
3146 or the given argument.
3152 Only applicable to threaded mode.
3153 Takes a message list and makes all replies to these messages invisible
3154 in header summaries, unless they are in state
3160 \*(OP\*(NQ Manage colour mappings for the type of colour given as the
3161 (case-insensitive) first argument, which must be one of
3163 for 256-colour terminals,
3168 for the standard 8-colour ANSI / ISO 6429 color palette and
3172 for monochrome terminals.
3173 Monochrome terminals cannot deal with colours, but only (some) font
3177 Without further arguments the list of all currently defined mappings
3178 for the given colour type is shown (as a special case giving
3182 will iterate over all types in order).
3183 Otherwise the second argument defines the mappable slot, the third
3184 argument a (comma-separated list of) colour and font attribute
3185 specification(s), and the optional fourth argument can be used to
3186 specify a precondition: if conditioned mappings exist they are tested in
3187 (creation) order unless a (case-insensitive) match has been found, and
3188 the default mapping (if any has been established) will only be chosen as
3190 The types of precondition available depend on the mappable slot, the
3191 following of which exist:
3194 Mappings prefixed with
3196 are used for the \*(OPal builtin Mailx-Line-Editor (MLE, see
3197 .Sx "On terminal control and line editor" )
3198 and don't support preconditions.
3200 .Bl -tag -compact -width view-partinfo
3202 This mapping is used for the position indicator that is visible when
3203 a line cannot be fully displayed on the screen.
3210 Mappings prefixed with
3212 are used in header summaries, and they all understand the preconditions
3214 (the current message) and
3216 for elder messages (only honoured in conjunction with
3217 .Va datefield-markout-older ) .
3219 .Bl -tag -compact -width view-partinfo
3221 This mapping is used for the
3223 that can be created with the
3227 formats of the variable
3230 For the complete header summary line except the
3232 and the thread structure.
3234 For the thread structure which can be created with the
3236 format of the variable
3241 Mappings prefixed with
3243 are used when displaying messages.
3245 .Bl -tag -compact -width view-partinfo
3247 This mapping is used for so-called
3249 lines, which are MBOX file format specific header lines.
3252 A comma-separated list of headers to which the mapping applies may be
3253 given as a precondition; if the \*(OPal regular expression support is
3254 available then if any of the
3256 (extended) regular expression characters is seen the precondition will
3257 be evaluated as (an extended) one.
3259 For the introductional message info line.
3260 .It Cd view-partinfo
3261 For MIME part info lines.
3265 The following (case-insensitive) colour definitions and font attributes
3266 are understood, multiple of which can be specified in a comma-separated
3276 It is possible (and often applicable) to specify multiple font
3277 attributes for a single mapping.
3280 foreground colour attribute:
3290 To specify a 256-color mode a decimal number colour specification in
3291 the range 0 to 255, inclusive, is supported, and interpreted as follows:
3293 .Bl -tag -compact -width "999 - 999"
3295 the standard ISO 6429 colors, as above.
3297 high intensity variants of the standard colors.
3299 216 colors in tuples of 6.
3301 grayscale from black to white in 24 steps.
3303 .Bd -literal -offset indent
3305 fg() { printf "\e033[38;5;${1}m($1)"; }
3306 bg() { printf "\e033[48;5;${1}m($1)"; }
3308 while [ $i -lt 256 ]; do fg $i; i=$(($i + 1)); done
3309 printf "\e033[0m\en"
3311 while [ $i -lt 256 ]; do bg $i; i=$(($i + 1)); done
3312 printf "\e033[0m\en"
3316 background colour attribute (see
3318 for possible values).
3322 Mappings may be removed with the command
3324 For a generic overview see the section
3325 .Sx "Coloured display" .
3330 (C) Copy messages to files whose names are derived from the author of
3331 the respective message and don't mark them as being saved;
3332 otherwise identical to
3337 (c) Copy messages to the named file and don't mark them as being saved;
3338 otherwise identical to
3343 \*(NQ With no arguments, shows all currently-defined custom headers.
3344 With one argument, shows that custom header.
3345 With more than one argument, creates a new or replaces an existing
3346 custom header with the name given as the first argument, the content of
3347 which being defined by the concatenated remaining arguments.
3349 can be used to delete custom headers.
3350 \*(ID Overwriting of automatically managed headers is neither supported
3352 Defined custom headers will be injected into newly composed or forwarded
3355 .Dl customhdr OpenPGP id=12345678; url=http://www.YYY.ZZ
3359 may also be used to inject custom headers; it is covered by
3364 Show the name of the current working directory.
3368 \*(OP For unencrypted messages this command is identical to
3370 Encrypted messages are first decrypted, if possible, and then copied.
3374 \*(OP For unencrypted messages this command is identical to
3376 Encrypted messages are first decrypted, if possible, and then copied.
3380 Without arguments the current list of macros, including their content,
3381 is shown, otherwise a macro is defined.
3382 A macro definition is a sequence of commands in the following form:
3383 .Bd -literal -offset indent
3392 A defined macro can be invoked explicitly by using the
3396 commands, or implicitly if a macro hook is triggered, e.g., a
3398 Note that interpretation of
3400 depends on how (i.e.,
3402 normal macro, folder hook, hook, account switch) the macro is invoked.
3403 Macros can be deleted via
3407 Macro behaviour, including option localization, will change in v15.
3408 Please be aware of that and possibly embed a version check in a resource
3413 (d) Marks the given message list as
3415 Deleted messages will neither be saved in
3417 nor will they be available for most other commands.
3429 Deletes the current message and displays the next message.
3430 If there is no next message, \*(UA says
3437 up or down by one message when given
3441 argument, respectively.
3445 Takes a message list and marks each given message as a draft.
3446 This mark has no technical meaning in the mail system;
3447 it just causes messages to be marked in the header summary,
3448 and makes them specially addressable.
3452 (ec) Echoes its arguments after applying
3454 expansions and filename transformations, as documented for
3459 (e) Point the text editor (as defined in
3461 at each message from the given list in turn.
3462 Modified contents are discarded unless the
3469 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3470 conditional \(em if the condition of a preceding
3472 was false, check the following condition and execute the following block
3473 if it evaluates true.
3478 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3479 conditional \(em if none of the conditions of the preceding
3483 commands was true, the
3489 (en) Marks the end of an
3490 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3491 conditional execution block.
3496 \*(NQ \*(UA has a strict notion about which variables are
3497 .Sx "INTERNAL VARIABLES"
3498 and which are managed in the program
3500 Since some of the latter are a vivid part of \*(UAs functioning,
3501 however, they are transparently integrated into the normal handling of
3502 internal variables via
3506 To integrate other environment variables of choice into this
3507 transparent handling, and also to export internal variables into the
3508 process environment where they normally are not, a
3510 needs to become established with this command, as in, e.g.,
3513 .Dl environ link PERL5LIB from TZ
3516 Afterwards changing such variables with
3518 will cause automatic updates of the program environment, and therefore
3519 be inherited by newly created child processes.
3520 Sufficient system support provided (it was in BSD as early as 1987, and
3521 is standardized since Y2K) removing such variables with
3523 will remove them also from the program environment, but in any way
3524 the knowledge they ever have been
3527 Note this implies that
3529 may cause loss of links.
3534 will remove an existing link, but leaves the variables as such intact.
3535 Additionally the subcommands
3539 are provided, which work exactly the same as the documented commands
3543 but (additionally) link the variable(s) with the program environment and
3544 thus immediately export them to, or remove them from (if possible),
3545 respectively, the program environment.
3550 \*(OP Since \*(UA uses the console as a user interface it can happen
3551 that messages scroll by too fast to become recognized.
3552 Optionally an error message ring queue is available which stores
3553 duplicates of any error message and notifies the user in interactive
3554 sessions whenever a new error has occurred.
3555 The queue is finite: if its maximum size is reached any new message
3556 replaces the eldest.
3559 can be used to manage this message queue: if given
3561 or no argument the queue will be displayed and cleared,
3563 will only clear all messages from the queue.
3567 (ex or x) Exit from \*(UA without changing the active mailbox and skip
3568 any saving of messages in
3570 as well as a possibly tracked line editor history file.
3576 but open the mailbox readonly.
3580 (fi) The file command switches to a new mailbox.
3581 Without arguments it shows status information of the current mailbox.
3582 If an argument is given, it will write out changes (such as deletions)
3583 the user has made and open a new mailbox.
3584 Some special conventions are recognized for the
3588 .Bl -tag -compact -offset indent -width ".Ar %:__lespec"
3590 (number sign) means the previous file,
3592 (percent sign) means the invoking user's system
3596 means the primary system mailbox of
3598 (and never the value of
3600 regardless of its actual setting),
3602 (ampersand) means the invoking user's
3612 expands to the same value as
3614 but the file is handled as a primary system mailbox by, e.g., the
3618 commands, meaning that messages that have been read in the current
3619 session will be moved to the
3621 mailbox instead of simply being flagged as read.
3624 If the name matches one of the strings defined with the command
3626 it is replaced by its long form and expanded.
3627 If the name ends with
3632 it is treated as being compressed with
3637 respectively, and transparently handled through an intermediate
3638 (un)compression step (using a temporary file) with the according
3639 facility, sufficient support provided.
3640 Likewise, if the named file doesn't exist, but a file with one of the
3641 mentioned compression extensions does, then the name is automatically
3642 expanded and the compressed file is used.
3644 Otherwise, if the name ends with an extension for which
3645 .Va file-hook-load-EXTENSION
3647 .Va file-hook-save-EXTENSION
3648 variables are set, then the given hooks will be used to load and save
3650 and \*(UA will work with an intermediate temporary file.
3652 MBOX files (flat file-based mailboxes) are generally locked during file
3653 operations in order to avoid inconsistencies due to concurrent
3655 \*(OPal Mailbox files which \*(UA treats as system
3657 boxes or primary mailboxes will also be protected by so-called dotlock
3658 files, the traditional way of mail spool file locking: for any file
3662 will be created for the duration of the synchronization \(em
3663 as necessary a privilege-separated dotlock child process will be used
3664 to accommodate for necessary privilege adjustments in order to create
3665 the dotlock file in the same directory
3666 and with the same user and group identities as the file of interest.
3669 for fine-tuning the handling of MBOX files.
3673 refers to a directory with the subdirectories
3678 then it is treated as a folder in
3680 format; \*(ID the variable
3682 can be used to control the format of yet non-existent folders.
3685 .Dl \*(IN protocol://[user[:password]@]host[:port][/path]
3686 .Dl \*(OU protocol://[user@]host[:port][/path]
3688 is taken as an Internet mailbox specification.
3689 The \*(OPally supported protocols are
3693 (POP3 with SSL/TLS encrypted transport).
3696 part is valid only for IMAP; there it defaults to
3698 Also see the section
3699 .Sx "On URL syntax and credential lookup" .
3703 contains special characters, in particular
3707 they must be escaped in URL notation \(en the command
3709 can be used to show the necessary conversion.
3713 Takes a message list and marks the messages as
3715 ged for urgent/special attention.
3716 This mark has no technical meaning in the mail system;
3717 it just causes messages to be highlighted in the header summary,
3718 and makes them specially addressable.
3727 With no arguments, list the names of the folders in the folder directory.
3728 With an existing folder as an argument,
3729 lists the names of folders below the named folder.
3735 but saves the message in a file named after the local part of the first
3736 recipient's address (instead of in
3743 but saves the message in a file named after the local part of the first
3744 recipient's address (instead of in
3751 but responds to all recipients regardless of the
3756 .It Ic followupsender
3759 but responds to the sender only regardless of the
3775 (f) Takes a list of message specifications and displays a summary of
3776 their message headers, exactly as via
3778 An alias of this command is
3781 .Sx "Specifying messages" .
3787 but saves the message in a file named after the local part of the
3788 recipient's address (instead of in
3793 Takes a message and the address of a recipient
3794 and forwards the message to him.
3795 The text of the original message is included in the new one,
3796 with the value of the
3798 variable preceding it.
3803 commands specify which header fields are included in the new message.
3804 Only the first part of a multipart message is included unless the
3805 .Va forward-as-attachment
3809 is set recipient addresses will be stripped from comments, names etc.
3813 Specifies which header fields are to be ignored with the command
3815 This command has no effect when the
3816 .Va forward-as-attachment
3821 Specifies which header fields are to be retained with the command
3826 This command has no effect when the
3827 .Va forward-as-attachment
3832 Define or list command aliases, so-called ghosts.
3833 Without arguments a list of all currently known aliases is shown.
3834 With one argument the expansion of the given alias is shown.
3835 With two or more arguments a command alias is defined or updated: the
3836 first argument is the name under which the remaining command line should
3837 be accessible, the content of which can be just about anything.
3838 A ghost can be used everywhere a normal command can be used, but always
3839 takes precedence; any arguments that are given to the command alias are
3840 joined onto the alias content, and the resulting string forms the
3841 command line that is, in effect, executed.
3844 .Bd -literal -offset indent
3846 `ghost': no such alias: "xx"
3849 ghost xx "echo hello,"
3858 (h) Show the current group of headers, the size of which depends on
3861 and the style of which can be adjusted with the variable
3863 If a message-specification is given the group of headers containing the
3864 first message therein is shown and the message at the top of the screen
3879 the list of history entries;
3882 argument selects and shows the respective history entry \(en
3885 to accept it, and the history entry will become the new history top.
3886 The default mode if no arguments are given is
3893 Takes a message list and marks each message therein to be saved in the
3898 Does not override the
3901 \*(UA deviates from the POSIX standard with this command, because a
3903 command issued after
3905 will display the following message, not the current one.
3910 (i) Part of the nestable
3911 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3912 conditional execution construct \(em if the given condition is true then
3913 the encapsulated block is executed.
3914 POSIX only supports the (case-insensitive) conditions
3919 end, all remaining conditions are non-portable extensions; note that
3920 falsely specified conditions cause the execution of the entire
3921 conditional construct until the (matching) closing
3923 command to be suppressed.
3924 The syntax of the nestable
3926 conditional execution construct requires that each condition and syntax
3927 element is surrounded by whitespace.
3929 .Bd -literal -offset indent
3938 The (case-insensitive) condition
3940 erminal will evaluate to true if the standard input is a terminal, i.e.,
3941 in interactive sessions.
3942 Another condition can be any boolean value (see the section
3943 .Sx "INTERNAL VARIABLES"
3944 for textual boolean representations) to mark an enwrapped block as
3947 .Dq always execute .
3948 It is possible to check
3949 .Sx "INTERNAL VARIABLES"
3952 variables for existence or compare their expansion against a user given
3953 value or another variable by using the
3955 .Pf ( Dq variable next )
3956 conditional trigger character;
3957 a variable on the right hand side may be signalled using the same
3959 The variable names may be enclosed in a pair of matching braces.
3962 The available comparison operators are
3966 (less than or equal to),
3972 (greater than or equal to),
3976 (is substring of) and
3978 (is not substring of).
3979 The values of the left and right hand side are treated as strings and
3980 are compared 8-bit byte-wise, ignoring case according to the rules of
3981 the US-ASCII encoding (therefore, dependent on the active locale,
3982 possibly producing false results for strings in the locale encoding).
3983 Except for the substring checks the comparison will instead be performed
3984 arithmetically if both, the user given value as well as the variable
3985 content, can be parsed as numbers (integers).
3986 An unset variable is treated as the empty string.
3989 When the \*(OPal regular expression support is available, the additional
3995 They treat the right hand side as an extended regular expression that is
3996 matched case-insensitively and according to the active
3998 locale, meaning that strings in the locale encoding should be matched
4002 Conditions can be joined via AND-OR lists (where the AND operator is
4004 and the OR operator is
4006 which have equal precedence and will be evaluated with left
4007 associativity, thus using the same syntax that is known for the
4009 It is also possible to form groups of conditions and lists by enclosing
4010 them in pairs of brackets
4011 .Ql [\ \&.\&.\&.\ ] ,
4012 which may be interlocked within each other, and also be joined via
4016 The results of individual conditions and entire groups may be modified
4017 via unary operators: the unary operator
4019 will reverse the result.
4021 .Bd -literal -offset indent
4025 if $ttycharset == "UTF-8"
4026 echo *ttycharset* is set to UTF-8, case-insensitively
4030 echo These two variables are equal
4032 if $version-major >= 15
4033 echo Running a new version..
4034 if $features =@ +regex
4035 if $TERM =~ "^xterm\&.*"
4036 echo ..in an X terminal
4039 if [ [ true ] && [ [ ${debug} ] || [ $verbose ] ] ]
4042 if true && $debug || ${verbose}
4043 echo Left associativity, as is known from the shell
4045 if ! ! true && ! [ ! $debug && ! $verbose ]
4046 echo Unary operator support
4054 Without arguments the list of ignored header fields is shown,
4055 otherwise the given list of header fields is added to the ignore list:
4056 Header fields in the ignore list are not shown on the terminal when
4057 a message is displayed.
4058 To display a message in its entirety, use the commands
4069 Shows the names of all available commands, alphabetically sorted.
4070 If given any non-whitespace argument the list will be shown in the order
4071 in which command prefixes are searched.
4074 output is available.
4078 This command can be used to localize changes to variables, meaning that
4079 their state will be reverted to the former one once the covered scope
4081 It can only be used inside of macro definition blocks introduced by
4085 and is interpreted as a boolean (string, see
4086 .Sx "INTERNAL VARIABLES" ) ;
4089 of an account is left once it is switched off again.
4090 .Bd -literal -offset indent
4091 define temporary_settings {
4106 enables change localization and calls
4108 which explicitly resets localization, then any value changes within
4110 will still be reverted by
4112 \*(ID Once the outermost level, the one which enabled localization
4113 first, is left, but no earlier, all adjustments will be unrolled.
4114 \*(ID Likewise worth knowing, if in this example
4116 changes to a different
4118 which sets some variables that are yet covered by localizations, their
4119 scope will be extended, and in fact leaving the
4121 will (thus) restore settings in (likely) global scope which actually
4122 were defined in a local, private context.
4126 Reply to messages that come in via known
4129 .Pf ( Ic mlsubscribe )
4130 mailing lists, or pretend to do so (see
4131 .Sx "Mailing lists" ) :
4134 functionality this will actively resort and even remove message
4135 recipients in order to generate a message that is supposed to be sent to
4137 For example it will also implicitly generate a
4138 .Ql Mail-Followup-To:
4139 header if that seems useful, regardless of the setting of the variable
4146 but saves the message in a file named after the local part of the first
4147 recipient's address (instead of in
4152 (m) Takes a (list of) recipient address(es) as (an) argument(s),
4153 or asks on standard input if none were given;
4154 then collects the remaining mail content and sends it out.
4158 (mb) The given message list is to be sent to
4160 when \*(UA is quit; this is the default action unless the
4163 \*(ID This command can only be used in a primary system mailbox (see
4168 Without any arguments the content of the MIME type cache will displayed.
4169 Otherwise each argument defines a complete MIME type specification of
4170 a type that shall be added (prepended) to the cache.
4171 In any event MIME type sources are loaded first as necessary \(en
4172 .Va mimetypes-load-control
4173 can be used to fine-tune which sources are actually loaded.
4174 Refer to the section on
4175 .Sx "The mime.types files"
4176 for more on MIME type specifications and this topic in general.
4177 MIME type unregistration and cache resets can be triggered with
4182 Without arguments the list of all currently defined mailing lists
4183 (and their attributes, if any) is shown; a more verbose listing will be
4184 produced if either of
4189 Otherwise all given arguments (which need not be quoted except for
4190 whitespace) will be added and henceforth be recognized as mailing lists.
4191 Mailing lists may be removed via the command
4194 If the \*(OPal regular expression support is available then mailing
4195 lists may also be specified as (extended) regular expressions (see
4201 Without arguments the list of all currently defined mailing lists which
4202 have a subscription attribute is shown; a more verbose listing will be
4203 produced if either of
4208 Otherwise this attribute will be set for all given mailing lists,
4209 newly creating them as necessary (as via
4211 Subscription attributes may be removed via the command
4220 but moves the messages to a file named after the local part of the
4221 sender address of the first message (instead of in
4228 but marks the messages for deletion if they were transferred
4235 but also displays ignored header fields and all MIME parts.
4243 on the given messages, even in non-interactive mode and as long as the
4244 standard output is a terminal.
4250 \*(OP When used without arguments or if
4252 has been given the content of the
4254 cache is shown, loading it first as necessary.
4257 then the cache will only be initialized and
4259 will remove its contents.
4260 Note that \*(UA will try to load the file only once, use
4261 .Ql Ic \&\&netrc Ns \:\0\:clear
4262 to unlock further attempts.
4267 .Sx "On URL syntax and credential lookup" ;
4269 .Sx "The .netrc file"
4270 documents the file format in detail.
4274 Checks for new mail in the current folder without committing any changes
4276 If new mail is present, a message is shown.
4280 the headers of each new message are also shown.
4281 This command is not available for all mailbox types.
4289 Goes to the next message in sequence and types it.
4290 With an argument list, types the next matching message.
4304 If the current folder is accessed via a network connection, a
4306 command is sent, otherwise no operation is performed.
4312 but also displays ignored header fields and all MIME parts.
4320 on the given messages, even in non-interactive mode and as long as the
4321 standard output is a terminal.
4329 but also pipes ignored header fields and all parts of MIME
4330 .Ql multipart/alternative
4335 (pi) Takes a message list and a shell command
4336 and pipes the messages through the command.
4337 Without an argument the current message is piped through the command
4344 every message is followed by a formfeed character.
4365 (q) Terminates the session, saving all undeleted, unsaved messages in
4368 preserving all messages marked with
4372 or never referenced in the system
4374 box, and removing all other messages from the primary system mailbox.
4375 If new mail has arrived during the session,
4377 .Dq You have new mail
4379 If given while editing a mailbox file with the command line flag
4381 then the edit file is rewritten.
4382 A return to the shell is effected,
4383 unless the rewrite of edit file fails,
4384 in which case the user can escape with the exit command.
4398 Removes the named files or directories.
4399 If a name refer to a mailbox, e.g., a Maildir mailbox, then a mailbox
4400 type specific removal will be performed, deleting the complete mailbox.
4401 The user is asked for confirmation in interactive mode.
4405 Takes the name of an existing folder
4406 and the name for the new folder
4407 and renames the first to the second one.
4408 Both folders must be of the same type.
4412 (R) Reply to originator.
4413 Does not reply to other recipients of the original message.
4415 will exchange this command with
4419 is set the recipient address will be stripped from comments, names etc.
4423 (r) Take a message and group-responds to it by addressing the sender
4426 .Va followup-to-honour ,
4429 .Va recipients-in-cc
4430 influence response behaviour.
4433 offers special support for replying to mailing lists.
4436 is set recipient addresses will be stripped from comments, names etc.
4449 but initiates a group-reply regardless of the value of
4456 but responds to the sender only regardless of the value of
4463 but does not add any header lines.
4464 This is not a way to hide the sender's identity,
4465 but useful for sending a message again to the same recipients.
4469 Takes a list of messages and a user name
4470 and sends each message to the named user.
4472 and related header fields are prepended to the new copy of the message.
4490 .It Ic respondsender
4496 (ret) Without arguments the list of retained header fields is shown,
4497 otherwise the given list of header fields is added to the retain list:
4498 Header fields in the retain list are shown on the terminal when
4499 a message is displayed, all other header fields are suppressed.
4500 To display a message in its entirety, use the commands
4509 takes precedence over the mentioned.
4515 but saves the messages in a file named after the local part of the
4516 sender of the first message instead of (in
4518 and) taking a filename argument.
4522 (s) Takes a message list and a filename and appends each message in turn
4523 to the end of the file.
4524 If no filename is given, the
4527 The filename in quotes, followed by the generated character count
4528 is echoed on the user's terminal.
4529 If editing a primary system mailbox the messages are marked for deletion.
4530 Filename interpretation as described for the
4532 command is performed.
4549 Header fields thus marked are filtered out when saving a message by
4551 or when automatically saving to
4553 This command should only be applied to header fields that do not contain
4554 information needed to decode the message,
4555 as MIME content fields do.
4567 Header fields thus marked are the only ones saved with a message when
4570 or when automatically saving to
4575 The use of this command is strongly discouraged since it may strip
4576 header fields that are needed to decode the message correctly.
4580 Takes a message specification (list) and displays a header summary of
4581 all matching messages, as via
4583 This command is an alias of
4586 .Sx "Specifying messages" .
4590 Takes a message list and marks all messages as having been read.
4594 (se) Without arguments this command shows all internal variables which
4595 are currently known to \*(UA (they have been set).
4596 A more verbose listing will be produced if either of
4600 are set, in which case variables may be preceded with a comment line
4601 that gives some context of what \*(UA knows about the given variable.
4603 Otherwise the given variables (and arguments) are set or adjusted.
4604 Arguments are of the form
4606 (no space before or after
4610 if there is no value, i.e., a boolean variable.
4611 Quotation marks may be placed around any part of the assignment
4612 statement to quote blanks or tabs, e.g.,
4614 .Dl set indentprefix='->'
4616 If an argument begins with
4620 the effect is the same as invoking the
4622 command with the remaining part of the variable
4623 .Pf ( Ql unset save ) .
4627 that is known to map to an environment variable will automatically cause
4628 updates in the program environment (unsetting a variable in the
4629 environment requires corresponding system support).
4630 Please use the command
4632 for further environmental control.
4637 .Sx "INTERNAL VARIABLES"
4643 (sh) Invokes an interactive version of the shell.
4647 Without arguments the list of all currently defined shortcuts is
4649 Otherwise all given arguments (which need not be quoted except for
4650 whitespace) are treated as pairs of shortcuts and their expansions,
4651 creating new or changing already existing shortcuts, as necessary.
4652 Shortcuts may be removed via the command
4654 The expansion strings should be in the syntax that has been described
4663 but performs neither MIME decoding nor decryption, so that the raw
4664 message text is shown.
4668 (si) Shows the size in characters of each message of the given
4673 Shows the current sorting criterion when used without an argument.
4674 Otherwise creates a sorted representation of the current folder,
4677 command and the addressing modes such that they refer to messages in
4679 Message numbers are the same as in regular mode.
4683 a header summary in the new order is also displayed.
4684 Automatic folder sorting can be enabled by setting the
4686 variable, as in, e.g.,
4687 .Ql set autosort=thread .
4688 Possible sorting criterions are:
4690 .Bl -tag -compact -offset indent -width "subject"
4692 Sort the messages by their
4694 field, that is by the time they were sent.
4696 Sort messages by the value of their
4698 field, that is by the address of the sender.
4701 variable is set, the sender's real name (if any) is used.
4703 Sort the messages by their size.
4705 \*(OP Sort the message by their spam score, as has been classified by
4708 Sort the messages by their message status.
4710 Sort the messages by their subject.
4712 Create a threaded display.
4714 Sort messages by the value of their
4716 field, that is by the address of the recipient.
4719 variable is set, the recipient's real name (if any) is used.
4724 (so) The source command reads commands from the given file, which is
4725 subject to the usual filename expansions (see introductional words of
4727 If the given argument ends with a vertical bar
4729 then the argument will instead be interpreted as a shell command and
4730 \*(UA will read the output generated by it.
4733 cannot be used from within macros that execute as
4734 .Va folder-hook Ns s
4737 i.e., it can only be called from macros that were
4744 (beside not supporting pipe syntax aka shell command input) is that
4745 this command will not generate an error if the given file argument
4746 cannot be opened successfully.
4747 This can matter in, e.g., resource files, since loading of those is
4748 stopped when an error is encountered.
4752 \*(OP Takes a list of messages and clears their
4758 \*(OP Takes a list of messages and causes the
4760 to forget it has ever used them to train its Bayesian filter.
4761 Unless otherwise noted the
4763 flag of the message is inspected to chose whether a message shall be
4771 \*(OP Takes a list of messages and informs the Bayesian filter of the
4775 This also clears the
4777 flag of the messages in question.
4781 \*(OP Takes a list of messages and rates them using the configured
4782 .Va spam-interface ,
4783 without modifying the messages, but setting their
4785 flag as appropriate; because the spam rating headers are lost the rate
4786 will be forgotten once the mailbox is left.
4787 Refer to the manual section
4789 for the complete picture of spam handling in \*(UA.
4793 \*(OP Takes a list of messages and sets their
4799 \*(OP Takes a list of messages and informs the Bayesian filter of the
4805 flag of the messages in question.
4814 Create a threaded representation of the current folder,
4815 i.\|e. indent messages that are replies to other messages in the header
4816 display and change the
4818 command and the addressing modes such that they refer to messages in the
4820 Message numbers are the same as in unthreaded mode.
4824 a header summary in threaded order is also displayed.
4838 (to) Takes a message list and types out the first
4840 lines of each message on the users' terminal.
4841 The only header fields that are displayed are
4848 will instead honour configured lists).
4849 It is possible to apply compression to what is displayed by setting
4851 Messages are decrypted and converted to the terminal character set
4856 (tou) Takes a message list and marks the messages for saving in
4858 \*(UA deviates from the POSIX standard with this command,
4861 command will display the following message instead of the current one.
4867 but also displays out ignored header fields and all parts of MIME
4868 .Ql multipart/alternative
4873 (t) Takes a message list and types out each message on the users'
4879 For MIME multipart messages, all parts with a content type of
4883 are shown, the other are hidden except for their headers.
4884 Messages are decrypted and converted to the terminal character set
4889 Delete all given accounts.
4890 An error message is shown if a given account is not defined.
4893 will discard all existing accounts.
4897 (una) Takes a list of names defined by alias commands
4898 and discards the remembered groups of users.
4901 will discard all existing aliases.
4905 Takes a message list and marks each message as not having been answered.
4911 ing, specified by its context and input sequence, both of which may be
4912 specified as a wildcard (asterisk,
4916 will remove all bindings of all contexts.
4920 Only applicable to threaded mode.
4921 Takes a message list and makes the message and all replies to it visible
4922 in header summaries again.
4923 When a message becomes the current message,
4924 it is automatically made visible.
4925 Also when a message with collapsed replies is displayed,
4926 all of these are automatically uncollapsed.
4932 mapping for the given colour type (see
4934 for a list of types) and mapping; if the optional precondition argument
4935 is used then only the exact tuple of mapping and precondition is removed.
4938 will remove all mappings (no precondition allowed).
4940 .Sx "Coloured display"
4941 for the general picture.
4945 Deletes the custom headers given as arguments.
4948 will remove all custom headers.
4952 Undefine all given macros.
4953 An error message is shown if a given macro is not defined.
4956 will discard all existing macros.
4960 (u) Takes a message list and marks each message as not being deleted.
4964 Takes a message list and
4970 Takes a message list and marks each message as not being
4975 Removes the header field names from the list of ignored fields for the
4980 will remove all fields.
4984 Removes the header field names from the list of retained fields for the
4989 will remove all fields.
4993 Remove all the given command
4997 will remove all ghosts.
5001 Removes the header field names from the list of ignored fields.
5004 will remove all fields.
5008 Delete all given MIME types, e.g.,
5009 .Ql unmimetype text/plain
5010 will remove all registered specifications for the MIME type
5014 will discard all existing MIME types, just as will
5016 but which also reenables cache initialization via
5017 .Va mimetypes-load-control .
5021 Forget about all the given mailing lists.
5024 will remove all lists.
5029 .It Ic unmlsubscribe
5030 Remove the subscription attribute from all given mailing lists.
5033 will clear the attribute from all lists which have it set.
5044 Takes a message list and marks each message as not having been read.
5048 Removes the header field names from the list of retained fields.
5051 will remove all fields.
5055 Removes the header field names from the list of ignored fields for
5059 will remove all fields.
5063 Removes the header field names from the list of retained fields for
5067 will remove all fields.
5071 (uns) Takes a list of internal variable names and discards their
5072 remembered values; the reverse of
5079 Deletes the shortcut names given as arguments.
5082 will remove all shortcuts.
5086 Disable sorted or threaded mode
5092 return to normal message order and,
5096 displays a header summary.
5106 Decode the given URL-encoded string arguments and show the results.
5107 Note the resulting strings may not be valid in the current locale, see
5112 URL-encode the given arguments and show the results.
5113 Because the arguments effectively are in the character set of the
5114 current locale the results will vary accordingly unless the input solely
5115 consists of characters in the portable character set, see
5116 .Sx "Character sets" .
5120 Edit the values of or create the given variable(s) in the
5122 Boolean variables cannot be edited.
5126 This command produces the same output as the listing mode of
5130 ity adjustments, but only for the given variables.
5134 \*(OP Takes a message list and verifies each message.
5135 If a message is not a S/MIME signed message,
5136 verification will fail for it.
5137 The verification process checks if the message was signed using a valid
5139 if the message sender's email address matches one of those contained
5140 within the certificate,
5141 and if the message content has been altered.
5145 Shows the version and feature set of \*(UA.
5149 (v) Takes a message list and invokes the display editor on each message.
5150 Modified contents are discarded unless the
5156 (w) For conventional messages the body without all headers is written.
5157 The output is decrypted and converted to its native format as necessary.
5158 If the output file exists, the text is appended.
5159 If a message is in MIME multipart format its first part is written to
5160 the specified file as for conventional messages,
5161 and the user is asked for a filename to save each other part.
5162 For convience saving of each part may be skipped by giving an empty value;
5163 the same result can also be achieved by writing it to
5165 For the second and subsequent parts a leading
5167 character causes the part to be piped to the remainder of the user input
5168 interpreted as a shell command;
5169 otherwise the user input is expanded as usually for folders,
5170 e.g., tilde expansion is performed.
5171 In non-interactive mode, only the parts of the multipart message
5172 that have a filename given in the part header are written,
5173 the others are discarded.
5174 The original message is never marked for deletion in the originating
5177 the contents of the destination file are overwritten if the file
5179 No special handling of compressed files is performed.
5188 \*(UA presents message headers in windowfuls as described under the
5191 This command scrolls to the next window of messages.
5192 If an argument is given, it specifies the window to use.
5193 A number prefixed by
5197 indicates that the window is calculated in relation to the current position.
5198 A number without a prefix specifies an absolute window number,
5201 lets \*(UA scroll to the last window of messages.
5207 but scrolls to the next or previous window that contains at least one
5216 .\" .Sh TILDE ESCAPES {{{
5219 Here is a summary of the tilde escapes,
5220 which are used to perform special functions when composing messages.
5221 Tilde escapes are only recognized at the beginning of lines.
5224 is somewhat of a misnomer since the actual escape character can be
5225 changed by adjusting the option
5228 .Bl -tag -width ".Ic __ filename"
5231 Insert the string of text in the message prefaced by a single
5233 (If the escape character has been changed,
5234 that character must be doubled
5235 in order to send it at the beginning of a line.)
5238 .It Ic ~! Ar command
5239 Execute the indicated shell
5241 then return to the message.
5245 Same effect as typing the end-of-file character.
5248 .It Ic ~: Ar \*(UA-command Ns \0or Ic ~_ Ar \*(UA-command
5249 Execute the given \*(UA command.
5250 Not all commands, however, are allowed.
5254 Write a summary of command escapes.
5257 .It Ic ~< Ar filename
5262 .It Ic ~<! Ar command
5264 is executed using the shell.
5265 Its standard output is inserted into the message.
5268 .It Ic ~@ Op Ar filename...
5269 With no arguments, edit the attachment list interactively.
5270 If an attachment's file name is left empty,
5271 that attachment is deleted from the list.
5272 When the end of the attachment list is reached,
5273 \*(UA will ask for further attachments until an empty name is given.
5274 If a given file name solely consists of the number sign
5276 followed by a valid message number of the currently active mailbox, then
5277 the given message is attached as a MIME
5279 and the rest of this section does not apply.
5281 If character set conversion has been compiled into \*(UA, then this mode
5282 gives the user the option to specify input and output character sets,
5283 unless the file extension indicates binary content, in which case \*(UA
5284 asks whether this step shall be skipped for the attachment in question.
5285 If not skipped, then the charset that succeeds to represent the
5286 attachment data will be used in the
5288 MIME parameter of the mail message:
5290 .Bl -bullet -compact
5292 If input and output character sets are specified, then the conversion is
5293 performed on the fly.
5294 The user will be asked repeatedly until the desired conversion succeeds.
5296 If only an output character set is specified, then the input is assumed
5299 charset and will be converted to the given output charset on the fly.
5300 The user will be asked repeatedly until the desired conversion succeeds.
5302 If no character sets are specified at all then the algorithm that is
5303 documented in the section
5304 .Sx "Character sets"
5305 is applied, but directly and on the fly.
5306 The user will be asked repeatedly until the desired conversion succeeds.
5308 Finally, if an input-, but no output character set is specified, then no
5309 conversion is ever performed, but the
5311 MIME parameter value will still be set to the user input.
5313 The character set selection loop can be left by typing
5315 i.e., causing an interrupt.
5316 .\" \*(OU next sentence
5317 Note that before \*(UA version 15.0 this terminates the entire
5318 current attachment selection, not only the character set selection.
5321 Without character set conversion support, \*(UA will ask for the input
5322 character set only, and it'll set the
5324 MIME parameter value to the given input, if any;
5325 if no user input is seen then the
5327 character set will be used for the parameter value instead.
5328 Note that the file extension check isn't performed in this mode, since
5329 no conversion will take place anyway.
5331 Note that in non-interactive mode, for reproduceabilities sake, there
5332 will always be two questions for each attachment, regardless of whether
5333 character set conversion is available and what the file extension is.
5334 The first asks for the filename, and the second asks for the input
5335 character set to be passed through to the corresponding MIME parameter;
5336 no conversion will be tried if there is input to the latter question,
5337 otherwise the usual conversion algorithm, as above, is applied.
5338 For message attachments, the answer to the second question is completely
5343 arguments are specified for the
5345 command they are treated as a file list of
5347 -style quoted arguments, optionally also separated by commas, which are
5348 expanded and then appended to the existing list of message attachments.
5349 Message attachments can only be added via the first method.
5350 In this mode the (text) attachments are assumed to be in
5352 encoding, and will be evaluated as documented in the section
5353 .Sx "Character sets" .
5357 Inserts the string contained in the
5360 .Ql Ic ~i Ns \0Sign ) .
5361 The escape sequences tabulator
5369 Inserts the string contained in the
5372 .Ql Ic ~i Ns \0sign ) .
5373 The escape sequences tabulator
5380 .It Ic ~b Ar name ...
5381 Add the given names to the list of blind carbon copy recipients.
5384 .It Ic ~c Ar name ...
5385 Add the given names to the list of carbon copy recipients.
5389 Read the file specified by the
5391 variable into the message.
5395 Invoke the text editor on the message collected so far.
5396 After the editing session is finished,
5397 the user may continue appending text to the message.
5400 .It Ic ~F Ar messages
5401 Read the named messages into the message being sent, including all
5402 message headers and MIME parts.
5403 If no messages are specified, read in the current message.
5406 .It Ic ~f Ar messages
5407 Read the named messages into the message being sent.
5408 If no messages are specified, read in the current message.
5412 lists are used to modify the message headers.
5413 For MIME multipart messages,
5414 only the first displayable part is included.
5418 Edit the message header fields
5423 by typing each one in turn and allowing the user to edit the field.
5424 The default values for these fields originate from the
5432 Edit the message header fields
5438 by typing each one in turn and allowing the user to edit the field.
5441 .It Ic ~i Ar variable
5442 Insert the value of the specified variable into the message,
5443 adding a newline character at the end.
5444 The message remains unaltered if the variable is unset or empty.
5445 The escape sequences tabulator
5452 .It Ic ~M Ar messages
5453 Read the named messages into the message being sent,
5456 If no messages are specified, read the current message.
5459 .It Ic ~m Ar messages
5460 Read the named messages into the message being sent,
5463 If no messages are specified, read the current message.
5467 lists are used to modify the message headers.
5468 For MIME multipart messages,
5469 only the first displayable part is included.
5473 Display the message collected so far,
5474 prefaced by the message header fields
5475 and followed by the attachment list, if any.
5479 Abort the message being sent,
5480 copying it to the file specified by the
5487 .It Ic ~R Ar filename
5488 Read the named file into the message, indented by
5492 .It Ic ~r Ar filename
5493 Read the named file into the message.
5497 Cause the named string to become the current subject field.
5500 .It Ic ~t Ar name ...
5501 Add the given name(s) to the direct recipient list.
5504 .It Ic ~U Ar messages
5505 Read in the given / current message(s) excluding all headers, indented by
5509 .It Ic ~u Ar messages
5510 Read in the given / current message(s), excluding all headers.
5514 Invoke an alternate editor (defined by the
5516 option) on the message collected so far.
5517 Usually, the alternate editor will be a screen editor.
5518 After the editor is quit,
5519 the user may resume appending text to the end of the message.
5522 .It Ic ~w Ar filename
5523 Write the message onto the named file.
5525 the message is appended to it.
5531 except that the message is not saved at all.
5534 .It Ic ~| Ar command
5535 Pipe the message through the specified filter command.
5536 If the command gives no output or terminates abnormally,
5537 retain the original text of the message.
5540 is often used as a rejustifying filter.
5545 .\" .Sh INTERNAL VARIABLES {{{
5546 .Sh "INTERNAL VARIABLES"
5548 Internal \*(UA variables are controlled via the
5552 commands; prefixing a variable name with the string
5556 has the same effect as using
5562 Creation or editing of variables can be performed in the
5567 will give more insight on the given variable(s), and
5569 when called without arguments, will show a listing of all variables.
5570 Some well-known variables will also become inherited from the
5573 implicitly, others can be explicitly imported with the command
5575 and henceforth share the said properties.
5578 Two different kind of internal variables exist.
5579 There are boolean variables, which can only be in one of the two states
5583 and value variables with a(n optional) string value.
5584 For the latter proper quoting is necessary upon assignment time, the
5585 introduction of the section
5587 documents the supported quoting rules.
5589 .Bd -literal -offset indent
5590 wysh set one=val\e 1 two="val 2" \e
5591 three='val "3"' four=$'val \e'4\e''
5592 varshow one two three four
5593 unset one two three four
5597 Dependent upon the actual option the string values will be interpreted
5598 as numbers, colour names, normal text etc., but there also exists
5599 a special kind of string value, the
5600 .Dq boolean string ,
5601 which must either be a decimal integer (in which case
5605 and any other value is true) or any of the (case-insensitive) strings
5611 for a false boolean and
5617 for a true boolean; a special kind of boolean string is the
5619 which is a boolean string that can optionally be prefixed with the
5620 (case-insensitive) term
5624 which causes prompting of the user in interactive mode, with the given
5625 boolean as the default value.
5627 .\" .Ss "Initial settings" {{{
5628 .\" (Keep in SYNC: ./nail.h:okeys, ./nail.rc, ./nail.1:"Initial settings")
5629 .Ss "Initial Settings"
5631 The standard POSIX 2008/Cor 1-2013 mandates the following initial
5637 .Pf no Va autoprint ,
5651 .Pf no Va ignoreeof ,
5653 .Pf no Va keepsave ,
5655 .Pf no Va outfolder ,
5660 (note that \*(UA deviates from the standard by using
5664 special prompt escape results in
5672 .Pf no Va sendwait ,
5681 Notes: \*(UA doesn't support the
5683 variable \(en use command line options or
5685 to pass options through to a
5687 And the default global
5689 file (which is loaded unless the
5691 command line flag has been used or the
5692 .Ev NAIL_NO_SYSTEM_RC
5693 environment variable is set) bends those initial settings a bit, e.g.,
5694 it sets the variables
5699 to name a few, calls
5701 etc., and should thus be taken into account.
5704 .\" .Ss "Variables" {{{
5707 .Bl -tag -width ".It Va _utoprin_"
5709 .It Va add-file-recipients
5710 \*(BO When file or pipe recipients have been specified,
5711 mention them in the corresponding address fields of the message instead
5712 of silently stripping them from their recipient list.
5713 By default such addressees are not mentioned.
5717 \*(BO Causes only the local part to be evaluated
5718 when comparing addresses.
5722 \*(BO Causes messages saved in
5724 to be appended to the end rather than prepended.
5725 This should always be set.
5729 \*(BO Causes \*(UA to prompt for the subject of each message sent.
5730 If the user responds with simply a newline,
5731 no subject field will be sent.
5735 \*(BO Causes the prompts for
5739 lists to appear after the message has been edited.
5743 \*(BO If set, \*(UA asks for files to attach at the end of each message,
5744 shall the list be found empty at that time.
5745 An empty line finalizes the list.
5749 \*(BO Causes the user to be prompted for carbon copy recipients
5750 (at the end of each message if
5754 are set) shall the list be found empty (at that time).
5755 An empty line finalizes the list.
5759 \*(BO Causes the user to be prompted for blind carbon copy
5760 recipients (at the end of each message if
5764 are set) shall the list be found empty (at that time).
5765 An empty line finalizes the list.
5769 \*(BO\*(OP Causes the user to be prompted if the message is to be
5770 signed at the end of each message.
5773 variable is ignored when this variable is set.
5777 \*(BO Alternative name for
5784 .It Va attachment-ask-content-description , \
5785 attachment-ask-content-disposition , \
5786 attachment-ask-content-id , \
5787 attachment-ask-content-type
5788 \*(BO If set then the user will be prompted for some attachment
5789 information when editing the attachment list.
5790 It is advisable to not use these but for the first of the variables;
5791 even for that it has to be noted that the data is used
5797 A sequence of characters to display in the
5801 as shown in the display of
5803 each for one type of messages (see
5804 .Sx "Message states" ) ,
5805 with the default being
5808 .Ql NU\ \ *HMFAT+\-$~
5811 variable is set, in the following order:
5813 .Bl -tag -compact -offset indent -width ".It Ql _"
5835 start of a collapsed thread.
5837 an uncollapsed thread (TODO ignored for now).
5841 classified as possible spam.
5847 Specifies a list of recipients to which a blind carbon copy of each
5848 outgoing message will be sent automatically.
5852 Specifies a list of recipients to which a carbon copy of each outgoing
5853 message will be sent automatically.
5857 \*(BO Causes threads to be collapsed automatically when threaded mode
5864 \*(BO Causes the delete command to behave like
5866 thus, after deleting a message the next one will be typed automatically.
5870 \*(BO\*(OB Causes threaded mode (see the
5872 command) to be entered automatically when a folder is opened.
5874 .Ql autosort=thread .
5878 Causes sorted mode (see the
5880 command) to be entered automatically with the value of this option as
5881 sorting method when a folder is opened, e.g.,
5882 .Ql set autosort=thread .
5886 \*(BO Enables the substitution of
5888 by the contents of the last command line in shell escapes.
5891 .It Va batch-exit-on-error
5892 \*(BO If the batch mode has been enabled via the
5894 command line option, then this variable will be consulted whenever \*(UA
5895 completes one operation (returns to the command prompt); if it is set
5896 then \*(UA will terminate if the last operation generated an error.
5900 \*(OP Terminals generate multi-byte sequences for certain forms of
5901 input, for example for function and other special keys.
5902 Some terminals however do not write these multi-byte sequences as
5903 a whole, but byte-by-byte, and the latter is what \*(UA actually reads.
5904 This variable specifies the timeout in milliseconds that the MLE (see
5905 .Sx "On terminal control and line editor" )
5906 waits for more bytes to arrive unless it considers a sequence
5912 \*(BO Causes automatic display of a header summary after executing a
5914 command, and thus complements the standard variable
5916 which controls header summary display on program startup.
5917 It is only meaningful if
5923 \*(BO Sets some cosmetical features to traditional BSD style;
5924 has the same affect as setting
5926 and all other variables prefixed with
5928 it also changes the meaning of the \*(UA specific
5931 escape sequence and changes behaviour of
5933 (which doesn't exist in BSD).
5937 \*(BO Changes the letters shown in the first column of a header
5938 summary to traditional BSD style.
5942 \*(BO Changes the display of columns in a header summary to traditional
5947 \*(BO Changes some informational messages to traditional BSD style.
5953 field to appear immediately after the
5955 field in message headers and with the
5957 .Sx "TILDE ESCAPES" .
5961 The value that should appear in the
5965 MIME header fields when no character set conversion of the message data
5967 This defaults to US-ASCII, and the chosen character set should be
5968 US-ASCII compatible.
5972 \*(OP The default 8-bit character set that is used as an implicit last
5973 member of the variable
5975 This defaults to UTF-8.
5976 If no character set conversion capabilities are available in \*(UA then
5977 the only supported character set is
5979 Refer to the section
5980 .Sx "Character sets"
5981 for the complete picture of character set conversion in \*(UA.
5984 .It Va charset-unknown-8bit
5985 \*(OP RFC 1428 specifies conditions when internet mail gateways shall
5987 the content of a mail message by using a character set with the name
5989 Because of the unclassified nature of this character set \*(UA will not
5990 be capable to convert this character set to any other character set.
5991 If this variable is set any message part which uses the character set
5993 is assumed to really be in the character set given in the value,
5994 otherwise the (final) value of
5996 is used for this purpose.
5998 This variable will also be taken into account if a MIME type (see
5999 .Sx "The mime.types files" )
6000 of a MIME message part that uses the
6002 character set is forcefully treated as text.
6006 The default value for the
6011 .It Va colour-disable
6012 \*(BO\*(OP Forcefully disable usage of colours.
6013 Also see the section
6014 .Sx "Coloured display" .
6018 \*(BO\*(OP Whether colour shall be used for output that is paged through
6020 Note that pagers may need special flags, e.g.,
6028 in order to support colours.
6029 Often doing manual adjustments is unnecessary since \*(UA may perform
6030 adjustments dependend on the value of the environment variable
6032 (see there for more).
6036 In a(n interactive) terminal session, then if this valued option is set
6037 it'll be used as a threshold to determine how many lines the given
6038 output has to span before it will be displayed via the configured
6042 can be forced by setting this to the value
6044 setting it without a value will deduce the current height of the
6045 terminal screen to compute the treshold (see
6053 \*(OB A variable counterpart of the
6055 command (see there for documentation), interpreted as a comma-separated
6056 list of custom headers to be injected, to include commas in the header
6057 bodies escape them with reverse solidus, e.g.:
6059 .Dl set customhdr='Hdr1: Body1-1\e, Body1-2, Hdr2: Body2'
6065 the message date, if any is to be displayed according to the format of
6067 is by default taken from the
6069 line of the message.
6070 If this variable is set the date as given in the
6072 header field is used instead, converted to local time.
6073 To control the display format of the date assign a valid
6078 format should not be used, because \*(UA doesn't take embedded newlines
6079 into account when calculating how many lines fit onto the screen.)
6081 .Va datefield-markout-older .
6084 .It Va datefield-markout-older
6085 This option, when set in addition to
6089 messages (concept is rather comparable to the
6091 option of the POSIX utility
6093 The content interpretation is identical to
6098 \*(BO Enables debug messages and obsoletion warnings, disables the
6099 actual delivery of messages and also implies
6105 .It Va disposition-notification-send
6107 .Ql Disposition-Notification-To:
6108 header (RFC 3798) with the message.
6112 .\" TODO .It Va disposition-notification-send-HOST
6114 .\".Va disposition-notification-send
6115 .\" for SMTP accounts on a specific host.
6116 .\" TODO .It Va disposition-notification-send-USER@HOST
6118 .\".Va disposition-notification-send
6119 .\"for a specific account.
6123 \*(BO When dot is set, a period
6125 on a line by itself during message input in (interactive) compose mode
6126 will be treated as end-of-message (in addition to the normal end-of-file
6135 .It Va dotlock-ignore-error
6136 \*(BO\*(OP Synchronization of mailboxes which \*(UA treats as system
6137 mailboxes (see the command
6139 will be protected with so-called dotlock files\(emthe traditional mail
6140 spool file locking method\(emin addition to system file locking.
6141 Because \*(UA ships with a privilege-separated dotlock creation program
6142 that should always be able to create such a dotlock file there is no
6143 good reason to ignore dotlock file creation errors, and thus these are
6144 fatal unless this variable is set.
6148 \*(BO If this variable is set then the editor is started automatically
6149 when a message is composed in interactive mode, as if the
6155 variable is implied for this automatically spawned editor session.
6159 \*(BO When a message is edited while being composed,
6160 its header is included in the editable text.
6170 fields are accepted within the header, other fields are ignored.
6174 \*(BO When entering interactive mode \*(UA normally writes
6175 .Dq \&No mail for user
6176 and exits immediately if a mailbox is empty or doesn't exist.
6177 If this option is set \*(UA starts even with an empty or nonexistent
6178 mailbox (the latter behaviour furtherly depends upon
6184 Suggestion for the MIME encoding to use in outgoing text messages
6186 Valid values are the default
6187 .Ql quoted-printable ,
6192 may cause problems when transferring mail messages over channels that
6193 are not ESMTP (RFC 1869) compliant.
6194 If there is no need to encode a message,
6196 transfer mode is always used regardless of this variable.
6197 Binary data is always encoded as
6202 If defined, the first character of this option
6203 gives the character to use in place of
6206 .Sx "TILDE ESCAPES" .
6210 If not set then file and command pipeline targets are not allowed,
6211 and any such address will be filtered out, giving a warning message.
6212 If set without a value then all possible recipient address
6213 specifications will be accepted \(en see the section
6214 .Sx "On sending mail, and non-interactive mode"
6216 To accept them, but only in interactive mode, or when tilde commands
6217 were enabled explicitly by using one of the command line options
6221 set this to the (case-insensitive) value
6223 (note right now this is actually like setting
6224 .Ql restrict,-all,+name,+addr ) .
6226 In fact the value is interpreted as a comma-separated list of values.
6229 then the existence of disallowed specifications is treated as a hard
6230 send error instead of only filtering them out.
6231 The remaining values specify whether a specific type of recipient
6232 address specification is allowed (optionally indicated by a plus sign
6234 prefix) or disallowed (prefixed with a hyphen
6238 addresses all possible address specifications,
6242 command pipeline targets,
6244 plain user names and (MTA) aliases (\*(OB
6246 may be used as an alternative syntax to
6251 These kind of values are interpreted in the given order, so that
6252 .Ql restrict,\:fail,\:+file,\:-all,\:+addr
6253 will cause hard errors for any non-network address recipient address
6254 unless \*(UA is in interactive mode or has been started with the
6258 command line option; in the latter case(s) any address may be used, then.
6262 Unless this variable is set additional
6264 (Mail-Transfer-Agent)
6265 arguments from the command line, as can be given after a
6267 separator, are ignored due to safety reasons.
6268 However, if set to the special (case-insensitive) value
6270 then the presence of additional MTA arguments is treated as a hard
6271 error that causes \*(UA to exit with failure status.
6272 A lesser strict variant is the otherwise identical
6274 which does accept such arguments in interactive mode, or if tilde
6275 commands were enabled explicitly by using one of the command line options
6282 \*(RO String giving a list of features \*(UA, preceded with a plus-sign
6284 if the feature is available, and a minus-sign
6287 The output of the command
6289 will include this information.
6293 \*(BO This option reverses the meanings of a set of reply commands,
6294 turning the lowercase variants, which by default address all recipients
6295 included in the header of a message
6296 .Pf ( Ic reply , respond , followup )
6297 into the uppercase variants, which by default address the sender only
6298 .Pf ( Ic Reply , Respond , Followup )
6301 .Ic replysender , respondsender , followupsender
6303 .Ic replyall , respondall , followupall
6304 are not affected by the current setting of
6309 .It Va file-hook-load-EXTENSION , file-hook-save-EXTENSION
6310 It is possible to install file hooks which will be used by the
6312 command in order to be able to transparently handle (through an
6313 intermediate temporary file) files with specific
6315 s: the variable values can include shell snippets and are expected to
6316 write data to standard output / read data from standard input,
6318 \*(ID The variables may not be changed while there is a mailbox
6320 .Bd -literal -offset indent
6321 set file-hook-load-xy='echo >&2 XY-LOAD; gzip -cd' \e
6322 file-hook-save-xy='echo >&2 XY-SAVE; gzip -c' \e
6323 record=+null-sent.xy
6328 The default path under which mailboxes are to be saved:
6329 file names that begin with the plus-sign
6331 will be expanded by prefixing them with the value of this variable.
6332 The same special syntax conventions as documented for the
6334 command may be used; if the non-empty value doesn't start with a solidus
6338 will be prefixed automatically.
6339 If unset or the empty string any
6341 prefixing file names will remain unexpanded.
6345 This variable can be set to the name of a
6347 macro which will be called whenever a
6350 The macro will also be invoked when new mail arrives,
6351 but message lists for commands executed from the macro
6352 only include newly arrived messages then.
6354 are activated by default in a folder hook, causing the covered settings
6355 to be reverted once the folder is left again.
6358 Macro behaviour, including option localization, will change in v15.
6359 Please be aware of that and possibly embed a version check in a resource
6363 .It Va folder-hook-FOLDER
6368 Unlike other folder specifications, the fully expanded name of a folder,
6369 without metacharacters, is used to avoid ambiguities.
6370 However, if the mailbox resides under
6374 specification is tried in addition, e.g., if
6378 (and thus relative to the user's home directory) then
6379 .Pa /home/usr1/mail/sent
6381 .Ql folder-hook-/home/usr1/mail/sent
6382 first, but then followed by
6383 .Ql folder-hook-+sent .
6387 \*(BO Controls whether a
6388 .Ql Mail-Followup-To:
6389 header is generated when sending messages to known mailing lists.
6391 .Va followup-to-honour
6393 .Ic mlist , mlsubscribe , reply
6398 .It Va followup-to-honour
6400 .Ql Mail-Followup-To:
6401 header is honoured when group-replying to a message via
6405 This is a quadoption; if set without a value it defaults to
6415 .It Va forward-as-attachment
6416 \*(BO Original messages are normally sent as inline text with the
6419 and only the first part of a multipart message is included.
6420 With this option messages are sent as unmodified MIME
6422 attachments with all of their parts included.
6426 The address (or a list of addresses) to put into the
6428 field of the message header, quoting RFC 5322:
6429 the author(s) of the message, that is, the mailbox(es) of the person(s)
6430 or system(s) responsible for the writing of the message.
6433 ing to messages these addresses are handled as if they were in the
6437 If the machine's hostname is not valid at the Internet (for example at
6438 a dialup machine) then either this variable or
6440 (\*(IN and with a defined SMTP protocol in
6443 adds even more fine-tuning capabilities),
6447 contains more than one address,
6450 variable is required (according to the standard RFC 5322).
6454 \*(BO When replying to or forwarding a message \*(UA normally removes
6455 the comment and name parts of email addresses.
6456 If this variable is set such stripping is not performed,
6457 and comments, names etc. are retained.
6461 The string to put before the text of a message with the
6465 .Va forward-as-attachment
6468 .Dq -------- Original Message --------
6469 if unset; No heading is put if it is set to the empty string.
6473 \*(BO Causes the header summary to be written at startup and after
6474 commands that affect the number of messages or the order of messages in
6475 the current folder; enabled by default.
6476 The command line option
6482 complements this and controls header summary display on folder changes.
6487 A format string to use for the summary of
6489 similar to the ones used for
6492 Format specifiers in the given string start with a percent character
6494 and may be followed by an optional decimal number indicating the field
6495 width \(em if that is negative, the field is to be left-aligned.
6496 Valid format specifiers are:
6499 .Bl -tag -compact -offset indent -width "_%%_"
6501 A plain percent character.
6504 a space character but for the current message
6506 for which it expands to
6510 a space character but for the current message
6512 for which it expands to
6515 \*(OP The spam score of the message, as has been classified via the
6518 Shows only a replacement character if there is no spam support.
6520 Message attribute character (status flag); the actual content can be
6524 The date when the message was received, or the date found in the
6528 variable is set (optionally to a date display format string).
6530 The indenting level in threaded mode.
6532 The address of the message sender.
6534 The message thread tree structure.
6535 (Note that this format doesn't support a field width.)
6537 The number of lines of the message, if available.
6541 The number of octets (bytes) in the message, if available.
6543 Message subject (if any).
6545 Message subject (if any) in double quotes.
6547 Message recipient flags: is the addressee of the message a known or
6548 subscribed mailing list \(en see
6553 The position in threaded/sorted order.
6557 .Ql %>\&%a\&%m\ %-18f\ %16d\ %4l/%\-5o\ %i%-s ,
6559 .Ql %>\&%a\&%m\ %20-f\ \ %16d\ %3l/%\-5o\ %i%-S
6570 .It Va headline-bidi
6571 Bidirectional text requires special treatment when displaying headers,
6572 because numbers (in dates or for file sizes etc.) will not affect the
6573 current text direction, in effect resulting in ugly line layouts when
6574 arabic or other right-to-left text is to be displayed.
6575 On the other hand only a minority of terminals is capable to correctly
6576 handle direction changes, so that user interaction is necessary for
6578 Note that extended host system support is required nonetheless, e.g.,
6579 detection of the terminal character set is one precondition;
6580 and this feature only works in an Unicode (i.e., UTF-8) locale.
6582 In general setting this variable will cause \*(UA to encapsulate text
6583 fields that may occur when displaying
6585 (and some other fields, like dynamic expansions in
6587 with special Unicode control sequences;
6588 it is possible to fine-tune the terminal support level by assigning
6590 no value (or any value other than
6595 will make \*(UA assume that the terminal is capable to properly deal
6596 with Unicode version 6.3, in which case text is embedded in a pair of
6597 U+2068 (FIRST STRONG ISOLATE) and U+2069 (POP DIRECTIONAL ISOLATE)
6599 In addition no space on the line is reserved for these characters.
6601 Weaker support is chosen by using the value
6603 (Unicode 6.3, but reserve the room of two spaces for writing the control
6604 sequences onto the line).
6609 select Unicode 1.1 support (U+200E, LEFT-TO-RIGHT MARK); the latter
6610 again reserves room for two spaces in addition.
6614 \*(OP If a line editor is available then this can be set to
6615 name the (expandable) path of the location of a permanent history file.
6618 .It Va history-gabby
6619 \*(BO\*(OP Add more entries to the history as is normally done.
6622 .It Va history-gabby-persist
6623 \*(BO\*(OP \*(UA's own MLE will not save the additional
6625 entries in persistent storage unless this variable is set.
6626 On the other hand it will not loose the knowledge of whether
6627 a persistent entry was gabby or not.
6633 \*(OP If a line editor is available this value restricts the
6634 amount of history entries that are saved into a set and valid
6636 A value of less than 0 disables this feature;
6637 note that loading and incorporation of
6639 upon program startup can also be suppressed by doing this.
6640 If unset or 0, a default value will be used.
6641 Dependent on the available line editor this will also define the
6642 number of history entries in memory;
6643 it is also editor-specific whether runtime updates of this value will
6648 \*(BO This option is used to hold messages in the system
6650 box, and it is set by default.
6654 Use this string as hostname when expanding local addresses instead of
6655 the value obtained from
6664 Note that when SMTP transport is not used (via
6666 then it is normally the responsibility of the MTA to create these
6667 fields, \*(IN in conjunction with SMTP however
6669 also influences the results:
6670 you should produce some test messages with the desired combination of
6679 \*(BO\*(OP Can be used to turn off the automatic conversion of domain
6680 names according to the rules of IDNA (internationalized domain names
6682 Since the IDNA code assumes that domain names are specified with the
6684 character set, an UTF-8 locale charset is required to represent all
6685 possible international domain names (before conversion, that is).
6689 \*(BO Ignore interrupt signals from the terminal while entering
6690 messages; instead echo them as
6692 characters and discard the current line.
6696 \*(BO Ignore end-of-file conditions
6697 .Pf ( Ql control-D )
6698 in compose mode on message input and in interactive command input.
6699 If set an interactive command input session can only be left by
6700 explicitly using one of the commands
6704 and message input in compose mode can only be terminated by entering
6707 on a line by itself or by using the
6709 .Sx "TILDE ESCAPES" ;
6711 overrides a setting of
6723 option for indenting messages,
6724 in place of the normal tabulator character
6726 which is the default.
6727 Be sure to quote the value if it contains spaces or tabs.
6731 \*(BO If set, an empty mailbox file is not removed.
6732 This may improve the interoperability with other mail user agents
6733 when using a common folder directory, and prevents malicious users
6734 from creating fake mailboxes in a world-writable spool directory.
6735 Note this only applies to local regular (MBOX) files, other mailbox
6736 types will never be removed.
6739 .It Va keep-content-length
6740 \*(BO When (editing messages and) writing
6742 mailbox files \*(UA can be told to keep the
6746 header fields that some MUAs generate by setting this variable.
6747 Since \*(UA does neither use nor update these non-standardized header
6748 fields (which in itself shows one of their conceptual problems),
6749 stripping them should increase interoperability in between MUAs that
6750 work with with same mailbox files.
6751 Note that, if this is not set but
6752 .Va writebackedited ,
6753 as below, is, a possibly performed automatic stripping of these header
6754 fields already marks the message as being modified.
6758 \*(BO When a message is saved it is usually discarded from the
6759 originating folder when \*(UA is quit.
6760 Setting this option causes all saved message to be retained.
6763 .It Va line-editor-disable
6764 \*(BO Turn off any enhanced line editing capabilities (see
6765 .Sx "On terminal control and line editor"
6769 .It Va line-editor-no-defaults
6770 \*(BO\*(OP Do not establish any default key binding.
6774 \*(BO When a message is replied to and this variable is set,
6775 it is marked as having been answered.
6776 This mark has no technical meaning in the mail system;
6777 it just causes messages to be marked in the header summary,
6778 and makes them specially addressable.
6782 \*(BO \*(UA generates and expects RFC 4155 compliant MBOX text
6784 (With the restriction that RFC 4155 defines seven-bit clean data
6785 storage, but which can be overwritten by a contrary setting of
6787 Messages which are fetched over the network or from within already
6788 existing Maildir (or any non-MBOX) mailboxes may require so-called
6790 quoting (insertion of additional
6792 characters to prevent line content misinterpretation) to be applied in
6793 order to be storable in MBOX mailboxes, however, dependent on the
6794 circumspection of the message producer.
6795 E.g., \*(UA itself will, when newly generating messages, choose a
6796 .Pf Content-Transfer- Va encoding
6797 that prevents the necessity for such quoting \(en a necessary
6798 precondition to ensure message checksums won't change.
6800 By default \*(UA will perform this
6802 quoting in a way that results in a MBOX file that is compatible with
6803 the POSIX MBOX layout, which means that, in order not to exceed the
6804 capabilities of simple applications, many more
6806 lines get quoted (thus modified) than necessary according to RFC 4155.
6807 Set this option to instead generate MBOX files which comply to RFC 4155.
6811 \*(BO Internal development variable.
6814 .It Va message-id-disable
6815 \*(BO By setting this option the generation of
6817 can be completely suppressed, effectively leaving this task up to the
6819 (Mail-Transfer-Agent) or the SMTP server.
6820 (According to RFC 5321 your SMTP server is not required to add this
6821 field by itself, so you should ensure that it accepts messages without a
6825 .It Va message-inject-head
6826 A string to put at the beginning of each new message.
6827 The escape sequences tabulator
6834 .It Va message-inject-tail
6835 A string to put at the end of each new message.
6836 The escape sequences tabulator
6844 \*(BO Usually, when an
6846 expansion contains the sender, the sender is removed from the expansion.
6847 Setting this option suppresses these removals.
6852 option to be passed through to the
6854 (Mail-Transfer-Agent); though most of the modern MTAs no longer document
6855 this flag, no MTA is known which doesn't support it (for historical
6859 .It Va mime-allow-text-controls
6860 \*(BO When sending messages, each part of the message is MIME-inspected
6861 in order to classify the
6864 .Ql Content-Transfer-Encoding:
6867 that is required to send this part over mail transport, i.e.,
6868 a computation rather similar to what the
6870 command produces when used with the
6874 This classification however treats text files which are encoded in
6875 UTF-16 (seen for HTML files) and similar character sets as binary
6876 octet-streams, forcefully changing any
6881 .Ql application/octet-stream :
6882 If that actually happens a yet unset charset MIME parameter is set to
6884 effectively making it impossible for the receiving MUA to automatically
6885 interpret the contents of the part.
6887 If this option is set, and the data was unambiguously identified as text
6888 data at first glance (by a
6892 file extension), then the original
6894 will not be overwritten.
6897 .It Va mime-alternative-favour-rich
6898 \*(BO If this variable is set then rich MIME alternative parts (e.g.,
6899 HTML) will be preferred in favour of included plain text versions when
6900 displaying messages, provided that a handler exists which produces
6901 output that can be (re)integrated into \*(UA's normal visual display.
6902 (E.g., at the time of this writing some newsletters ship their full
6903 content only in the rich HTML part, whereas the plain text part only
6904 contains topic subjects.)
6907 .It Va mime-counter-evidence
6910 field is used to decide how to handle MIME parts.
6911 Some MUAs however don't use
6913 or a similar mechanism to correctly classify content, but simply specify
6914 .Ql application/octet-stream ,
6915 even for plain text attachments like
6917 If this variable is set then \*(UA will try to classify such MIME
6918 message parts on its own, if possible, for example via a possibly
6919 existent attachment filename.
6920 A non-empty value may also be given, in which case a number is expected,
6921 actually a carrier of bits.
6922 Creating the bit-carrying number is a simple addition:
6923 .Bd -literal -offset indent
6924 ? !echo Value should be set to $((2 + 4 + 8))
6925 Value should be set to 14
6928 .Bl -bullet -compact
6930 If bit two is set (2) then the detected
6932 content-type will be carried along with the message and be used for
6934 .Va pipe-TYPE/SUBTYPE
6935 is responsible for the MIME part, shall that question arise;
6936 when displaying such a MIME part the part-info will indicate the
6937 overridden content-type by showing a plus-sign
6940 If bit three is set (4) then the counter-evidence is always produced
6941 and a positive result will be used as the MIME type, even forcefully
6942 overriding the parts given MIME type.
6944 If bit four is set (8) then as a last resort the actual content of
6945 .Ql application/octet-stream
6946 parts will be inspected, so that data which looks like plain text can be
6951 .It Va mimetypes-load-control
6952 This option can be used to control which of the
6954 databases are loaded by \*(UA, as furtherly described in the section
6955 .Sx "The mime.types files" .
6958 is part of the option value, then the user's personal
6960 file will be loaded (if it exists); likewise the letter
6962 controls loading of the system wide
6963 .Pa /etc/mime.types ;
6964 directives found in the user file take precedence, letter matching is
6966 If this option is not set \*(UA will try to load both files.
6967 Incorporation of the \*(UA-builtin MIME types cannot be suppressed,
6968 but they will be matched last.
6970 More sources can be specified by using a different syntax: if the
6971 value string contains an equals sign
6973 then it is instead parsed as a comma-separated list of the described
6976 pairs; the given filenames will be expanded and loaded, and their
6977 content may use the extended syntax that is described in the section
6978 .Sx "The mime.types files" .
6979 Directives found in such files always take precedence (are prepended to
6980 the MIME type cache).
6985 To choose an alternate Mail-Transfer-Agent, set this option to either
6986 the full pathname of an executable (optionally prefixed with a
6988 protocol indicator), or \*(OPally a SMTP protocol URL, e.g., \*(IN
6990 .Dl smtps?://[user[:password]@]server[:port]
6993 .Ql [smtp://]server[:port] . )
6994 The default has been chosen at compie time.
6995 All supported data transfers are executed in child processes, which
6996 run asynchronously, and without supervision, unless either the
7001 If such a child receives a TERM signal, it will abort and
7008 For a file-based MTA it may be necessary to set
7010 in in order to choose the right target of a modern
7013 It will be passed command line arguments from several possible sources:
7016 if set, from the command line if given and the variable
7019 Argument processing of the MTA will be terminated with a
7024 The otherwise occurring implicit usage of the following MTA command
7025 line arguments can be disabled by setting the boolean option
7026 .Va mta-no-default-arguments
7027 (which will also disable passing
7031 (for not treating a line with only a dot
7033 character as the end of input),
7041 option is set); in conjunction with the
7043 command line option \*(UA will also pass
7049 \*(OP \*(UA can send mail over SMTP network connections to a single
7050 defined SMTP smarthost, the access URL of which has to be assigned to
7052 To use this mode it is helpful to read
7053 .Sx "On URL syntax and credential lookup" .
7054 It may be necessary to set the
7056 variable in order to use a specific combination of
7061 with some mail providers.
7064 .Bl -bullet -compact
7066 The plain SMTP protocol (RFC 5321) that normally lives on the
7067 server port 25 and requires setting the
7068 .Va smtp-use-starttls
7069 variable to enter a SSL/TLS encrypted session state.
7070 Assign a value like \*(IN
7071 .Ql smtp://[user[:password]@]server[:port]
7073 .Ql smtp://server[:port] )
7074 to choose this protocol.
7076 The so-called SMTPS which is supposed to live on server port 465
7077 and is automatically SSL/TLS secured.
7078 Unfortunately it never became a standardized protocol and may thus not
7079 be supported by your hosts network service database
7080 \(en in fact the port number has already been reassigned to other
7083 SMTPS is nonetheless a commonly offered protocol and thus can be
7084 chosen by assigning a value like \*(IN
7085 .Ql smtps://[user[:password]@]server[:port]
7087 .Ql smtps://server[:port] ) ;
7088 due to the mentioned problems it is usually necessary to explicitly
7093 Finally there is the SUBMISSION protocol (RFC 6409), which usually
7094 lives on server port 587 and is practically identically to the SMTP
7095 protocol from \*(UA's point of view beside that; it requires setting the
7096 .Va smtp-use-starttls
7097 variable to enter a SSL/TLS secured session state.
7098 Assign a value like \*(IN
7099 .Ql submission://[user[:password]@]server[:port]
7101 .Ql submission://server[:port] ) .
7106 .It Va mta-arguments
7107 Arguments to pass through to a file-based
7109 can be given via this variable, the content of which will be split up in
7110 a vector of arguments, to be joined onto other possible MTA options:
7112 .Dl set mta-arguments='-t -X \&"/tmp/my log\&"'
7115 .It Va mta-no-default-arguments
7116 \*(BO Unless this option is set \*(UA will pass some well known
7117 standard command line options to a file-based
7119 (Mail-Transfer-Agent), see there for more.
7123 Many systems use a so-called
7125 environment to ensure compatibility with
7127 This works by inspecting the name that was used to invoke the mail
7129 If this variable is set then the mailwrapper (the program that is
7130 actually executed when calling the file-based
7132 will treat its contents as that name.
7137 .It Va NAIL_EXTRA_RC
7138 The name of an optional startup file to be read last.
7139 This variable has an effect only if it is set in any of the
7140 .Sx "Resource files" ,
7141 it is not imported from the environment.
7142 Use this file for commands that are not understood by other POSIX
7147 .It Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup
7148 \*(BO\*(IN\*(OP Used to control usage of the users
7150 file for lookup of account credentials, as documented in the section
7151 .Sx "On URL syntax and credential lookup"
7155 .Sx "The .netrc file"
7156 documents the file format.
7168 then \*(UA will read the output of a shell pipe instead of the users
7170 file if this variable is set (to the desired shell command).
7171 This can be used to, e.g., store
7175 .Dl set netrc-pipe='gpg -qd ~/.netrc.pgp'
7179 If this variable has the value
7181 newly created local folders will be in Maildir format.
7185 Checks for new mail in the current folder each time the prompt is shown.
7186 A Maildir folder must be re-scanned to determine if new mail has arrived.
7187 If this variable is set to the special value
7189 then a Maildir folder will not be rescanned completely, but only
7190 timestamp changes are detected.
7194 .It Va on-compose-enter , on-compose-leave
7195 \*(ID Macro hooks which will be executed before compose mode is
7196 entered, and after composing has been finished, respectively.
7197 Please note that this interface is very likely to change in v15, and
7198 should therefore possibly even be seen as experimental.
7200 are by default enabled for these hooks, causing any setting to be
7201 forgotten after the message has been sent.
7202 The following variables will be set temporarily during execution of the
7205 .Bl -tag -compact -width ".It Va compose_subject"
7208 .It Va compose-sender
7210 .It Va compose-to , compose-cc , compose-bcc
7211 The list of receiver addresses as a space-separated list.
7212 .It Va compose-subject
7218 \*(BO Causes the filename given in the
7221 and the sender-based filenames for the
7225 commands to be interpreted relative to the directory given in the
7227 variable rather than to the current directory,
7228 unless it is set to an absolute pathname.
7232 \*(BO If set, each message feed through the command given for
7234 is followed by a formfeed character
7238 .It Va password-USER@HOST , password-HOST , password
7239 \*(IN Variable chain that sets a password, which is used in case none has
7240 been given in the protocol and account-specific URL;
7241 as a last resort \*(UA will ask for a password on the user's terminal if
7242 the authentication method requires a password.
7243 Specifying passwords in a startup file is generally a security risk;
7244 the file should be readable by the invoking user only.
7246 .It Va password-USER@HOST
7247 \*(OU (see the chain above for \*(IN)
7248 Set the password for
7252 If no such variable is defined for a host,
7253 the user will be asked for a password on standard input.
7254 Specifying passwords in a startup file is generally a security risk;
7255 the file should be readable by the invoking user only.
7259 \*(BO Send messages to the
7261 command without performing MIME and character set conversions.
7265 .It Va pipe-TYPE/SUBTYPE
7266 When a MIME message part of type
7268 (case-insensitive) is displayed or quoted,
7269 its text is filtered through the value of this variable interpreted as
7273 forces interpretation of the message part as plain text, e.g.,
7274 .Ql set pipe-application/xml=@
7275 will henceforth display XML
7277 (The same could also be achieved by adding a MIME type marker with the
7280 And \*(OPally MIME type handlers may be defined via
7281 .Sx "The Mailcap files"
7282 \(em corresponding flag strings are shown in parenthesis below.)
7287 can in fact be used to adjust usage and behaviour of a following shell
7288 command specification by appending trigger characters to it, e.g., the
7289 following hypothetical command specification could be used:
7290 .Bd -literal -offset indent
7291 set pipe-X/Y='@*!++=@vim ${NAIL_FILENAME_TEMPORARY}'
7295 .Bl -tag -compact -width ".It Ql __"
7297 Simply by using the special
7299 prefix the MIME type (shell command) handler will only be invoked to
7300 display or convert the MIME part if the message is addressed directly
7301 and alone by itself.
7302 Use this trigger to disable this and always invoke the handler
7303 .Pf ( Cd x-mailx-always ) .
7306 If set the handler will not be invoked when a message is to be quoted,
7307 but only when it will be displayed
7308 .Pf ( Cd x-mailx-noquote ) .
7311 The command will be run asynchronously, i.e., without blocking \*(UA,
7312 which may be a handy way to display a, e.g., PDF file while also
7313 continuing to read the mail message
7314 .Pf ( Cd x-mailx-async ) .
7315 Asynchronous execution implies
7319 The command must be run on an interactive terminal, \*(UA will
7320 temporarily release the terminal to it
7321 .Pf ( Cd needsterminal ) .
7322 This flag is mutual exclusive with
7324 will only be used in interactive mode and implies
7328 Request creation of a zero-sized temporary file, the absolute pathname
7329 of which will be made accessible via the environment variable
7330 .Ev NAIL_FILENAME_TEMPORARY
7331 .Pf ( Cd x-mailx-tmpfile ) .
7332 If this trigger is given twice then the file will be unlinked
7333 automatically by \*(UA when the command loop is entered again at latest
7334 .Pf ( Cd x-mailx-tmpfile-unlink ) .
7335 (Don't use this for asynchronous handlers.)
7338 Normally the MIME part content is passed to the handler via standard
7339 input; if this flag is set then the data will instead be written into
7340 .Ev NAIL_FILENAME_TEMPORARY
7341 .Pf ( Cd x-mailx-tmpfile-fill ) ,
7342 the creation of which is implied; note however that in order to cause
7343 deletion of the temporary file you still have to use two plus signs
7348 To avoid ambiguities with normal shell command content you can use
7349 another at-sign to forcefully terminate interpretation of remaining
7351 (Any character not in this list will have the same effect.)
7355 Some information about the MIME part to be displayed is embedded into
7356 the environment of the shell command:
7359 .Bl -tag -compact -width ".It Ev _AIL__ILENAME__ENERATED"
7362 The MIME content-type of the part, if known, the empty string otherwise.
7365 .It Ev NAIL_CONTENT_EVIDENCE
7367 .Va mime-counter-evidence
7368 includes the carry-around-bit (2), then this will be set to the detected
7369 MIME content-type; not only then identical to
7370 .Ev \&\&NAIL_CONTENT
7374 .It Ev NAIL_FILENAME
7375 The filename, if any is set, the empty string otherwise.
7378 .It Ev NAIL_FILENAME_GENERATED
7382 .It Ev NAIL_FILENAME_TEMPORARY
7383 If temporary file creation has been requested through the command prefix
7384 this variable will be set and contain the absolute pathname of the
7389 The temporary directory that \*(UA uses.
7390 Usually identical to
7392 but guaranteed to be set and usable by child processes;
7393 to ensure the latter condition for
7400 .It Va pipe-EXTENSION
7401 This is identical to
7402 .Va pipe-TYPE/SUBTYPE
7405 (normalized to lowercase using character mappings of the ASCII charset)
7406 names a file extension, e.g.,
7408 Handlers registered using this method take precedence.
7411 .It Va pop3-auth-USER@HOST , pop3-auth-HOST , pop3-auth
7412 \*(OP\*(IN Variable chain that sets the POP3 authentication method.
7413 The only possible value as of now is
7415 which is thus the default.
7418 .Mx Va pop3-bulk-load
7419 .It Va pop3-bulk-load-USER@HOST , pop3-bulk-load-HOST , pop3-bulk-load
7420 \*(BO\*(OP When accessing a POP3 server \*(UA loads the headers of
7421 the messages, and only requests the message bodies on user request.
7422 For the POP3 protocol this means that the message headers will be
7424 If this option is set then \*(UA will download only complete messages
7425 from the given POP3 server(s) instead.
7427 .Mx Va pop3-keepalive
7428 .It Va pop3-keepalive-USER@HOST , pop3-keepalive-HOST , pop3-keepalive
7429 \*(OP POP3 servers close the connection after a period of inactivity;
7430 the standard requires this to be at least 10 minutes,
7431 but practical experience may vary.
7432 Setting this variable to a numeric value greater than
7436 command to be sent each value seconds if no other operation is performed.
7439 .It Va pop3-no-apop-USER@HOST , pop3-no-apop-HOST , pop3-no-apop
7440 \*(BO\*(OP Unless this variable is set the
7442 authentication method will be used when connecting to a POP3 server that
7446 is that the password is not sent in clear text over the wire and that
7447 only a single packet is sent for the user/password tuple.
7449 .Va pop3-no-apop-HOST
7452 .Mx Va pop3-use-starttls
7453 .It Va pop3-use-starttls-USER@HOST , pop3-use-starttls-HOST , pop3-use-starttls
7454 \*(BO\*(OP Causes \*(UA to issue a
7456 command to make an unencrypted POP3 session SSL/TLS encrypted.
7457 This functionality is not supported by all servers,
7458 and is not used if the session is already encrypted by the POP3S method.
7460 .Va pop3-use-starttls-HOST
7464 .It Va print-alternatives
7465 \*(BO When a MIME message part of type
7466 .Ql multipart/alternative
7467 is displayed and it contains a subpart of type
7469 other parts are normally discarded.
7470 Setting this variable causes all subparts to be displayed,
7471 just as if the surrounding part was of type
7472 .Ql multipart/mixed .
7476 The string shown when a command is accepted.
7477 Prompting may be prevented by setting this to the null string
7479 .Pf no Va prompt ) .
7480 If a value is assigned the following \*(UA specific additional sequences
7487 is set, in which case it expands to
7491 is the default value of
7494 which will expand to
7496 if the last command failed and to
7500 which will expand to the name of the currently active
7502 if any, and to the empty string otherwise, and
7504 which will expand to the name of the currently active mailbox.
7505 (Note that the prompt buffer is size-limited, excess is cut off.)
7511 to encapsulate the expansions of the
7515 escape sequences as necessary to correctly display bidirectional text,
7516 this is not true for the final string that makes up
7518 as such, i.e., real BIDI handling is not supported.
7522 \*(BO Suppresses the printing of the version when first invoked.
7526 If set, \*(UA starts a replying message with the original message
7527 prefixed by the value of the variable
7529 Normally, a heading consisting of
7530 .Dq Fromheaderfield wrote:
7531 is put before the quotation.
7536 variable, this heading is omitted.
7539 is assigned, the headers selected by the
7540 .Ic ignore Ns / Ns Ic retain
7541 commands are put above the message body,
7544 acts like an automatic
7550 is assigned, all headers are put above the message body and all MIME
7551 parts are included, making
7553 act like an automatic
7556 .Va quote-as-attachment .
7559 .It Va quote-as-attachment
7560 \*(BO Add the original message in its entirety as a
7562 MIME attachment when replying to a message.
7563 Note this works regardless of the setting of
7568 \*(OP Can be set in addition to
7570 Setting this turns on a more fancy quotation algorithm in that leading
7571 quotation characters are compressed and overlong lines are folded.
7573 can be set to either one or two (space separated) numeric values,
7574 which are interpreted as the maximum (goal) and the minimum line length,
7575 respectively, in a spirit rather equal to the
7577 program, but line-, not paragraph-based.
7578 If not set explicitly the minimum will reflect the goal algorithmically.
7579 The goal can't be smaller than the length of
7581 plus some additional pad.
7582 Necessary adjustments take place silently.
7585 .It Va recipients-in-cc
7586 \*(BO On group replies, specify only the sender of the original mail in
7588 and mention the other recipients in the secondary
7590 By default all recipients of the original mail will be addressed via
7595 If defined, gives the pathname of the folder used to record all outgoing
7597 If not defined, then outgoing mail is not saved.
7598 When saving to this folder fails the message is not sent,
7599 but instead saved to
7603 .It Va record-resent
7604 \*(BO If both this variable and the
7611 commands save messages to the
7613 folder as it is normally only done for newly composed messages.
7616 .It Va reply-in-same-charset
7617 \*(BO If this variable is set \*(UA first tries to use the same
7618 character set of the original message for replies.
7619 If this fails, the mechanism described in
7620 .Sx "Character sets"
7621 is evaluated as usual.
7624 .It Va reply_strings
7625 Can be set to a comma-separated list of (case-insensitive according to
7626 ASCII rules) strings which shall be recognized in addition to the
7629 reply message indicators \(en builtin are
7631 which is mandated by RFC 5322, as well as the german
7636 A list of addresses to put into the
7638 field of the message header.
7639 Members of this list are handled as if they were in the
7644 .It Va reply-to-honour
7647 header is honoured when replying to a message via
7651 This is a quadoption; if set without a value it defaults to
7655 .It Va rfc822-body-from_
7656 \*(BO This variable can be used to force displaying a so-called
7658 line for messages that are embedded into an envelope mail via the
7660 MIME mechanism, for more visual convenience.
7664 \*(BO Enable saving of (partial) messages in
7666 upon interrupt or delivery error.
7670 The number of lines that represents a
7679 line display and scrolling via
7681 If this variable is not set \*(UA falls back to a calculation based upon
7682 the detected terminal window size and the baud rate: the faster the
7683 terminal, the more will be shown.
7684 Overall screen dimensions and pager usage is influenced by the
7685 environment variables
7693 .It Va searchheaders
7694 \*(BO Expand message-list specifiers in the form
7696 to all messages containing the substring
7700 The string search is case insensitive.
7704 \*(OP A comma-separated list of character set names that can be used in
7705 outgoing internet mail.
7706 The value of the variable
7708 is automatically appended to this list of character-sets.
7709 If no character set conversion capabilities are compiled into \*(UA then
7710 the only supported charset is
7713 .Va sendcharsets-else-ttycharset
7714 and refer to the section
7715 .Sx "Character sets"
7716 for the complete picture of character set conversion in \*(UA.
7719 .It Va sendcharsets-else-ttycharset
7720 \*(BO\*(OP If this variable is set, but
7722 is not, then \*(UA acts as if
7724 had been set to the value of the variable
7726 In effect this combination passes through the message data in the
7727 character set of the current locale (given that
7729 hasn't been set manually), i.e., without converting it to the
7731 fallback character set.
7732 Thus, mail message text will be in ISO-8859-1 encoding when send from
7733 within a ISO-8859-1 locale, and in UTF-8 encoding when send from within
7735 If no character set conversion capabilities are available in \*(UA then
7736 the only supported character set is
7741 An address that is put into the
7743 field of outgoing messages, quoting RFC 5322: the mailbox of the agent
7744 responsible for the actual transmission of the message.
7745 This field should normally not be used unless the
7747 field contains more than one address, on which case it is required.
7750 address is handled as if it were in the
7756 \*(OB Predecessor of
7760 .It Va sendmail-arguments
7761 \*(OB Predecessor of
7765 .It Va sendmail-no-default-arguments
7766 \*(OB\*(BO Predecessor of
7767 .Va mta-no-default-arguments .
7770 .It Va sendmail-progname
7771 \*(OB Predecessor of
7776 \*(BO When sending a message wait until the
7778 (including the builtin SMTP one) exits before accepting further commands.
7780 with this variable set errors reported by the MTA will be recognizable!
7781 If the MTA returns a non-zero exit status,
7782 the exit status of \*(UA will also be non-zero.
7786 \*(BO Setting this option causes \*(UA to start at the last message
7787 instead of the first one when opening a mail folder.
7791 \*(BO Causes \*(UA to use the sender's real name instead of the plain
7792 address in the header field summary and in message specifications.
7796 \*(BO Causes the recipient of the message to be shown in the header
7797 summary if the message was sent by the user.
7801 A string for use with the
7807 A string for use with the
7813 Must correspond to the name of a readable file if set.
7814 The file's content is then appended to each singlepart message
7815 and to the first part of each multipart message.
7816 Be warned that there is no possibility to edit the signature for an
7820 .It Va skipemptybody
7821 \*(BO If an outgoing message does not contain any text in its first or
7822 only message part, do not send it but discard it silently (see also the
7828 \*(OP Specifies a directory with CA certificates in PEM (Privacy
7829 Enhanced Mail) format for verification of S/MIME signed messages.
7832 .It Va smime-ca-file
7833 \*(OP Specifies a file with CA certificates in PEM format for
7834 verification of S/MIME signed messages.
7837 .It Va smime-cipher-USER@HOST , smime-cipher
7838 \*(OP Specifies the cipher to use when generating S/MIME encrypted
7839 messages (for the specified account).
7840 RFC 5751 mandates a default of
7843 Possible values are (case-insensitive and) in decreasing cipher strength:
7851 (DES EDE3 CBC, 168 bits; default if
7853 isn't available) and
7857 The actually available cipher algorithms depend on the cryptographic
7858 library that \*(UA uses.
7859 \*(OP Support for more cipher algorithms may be available through
7860 dynamic loading via, e.g.,
7861 .Xr EVP_get_cipherbyname 3
7862 (OpenSSL) if \*(UA has been compiled to support this.
7865 .It Va smime-crl-dir
7866 \*(OP Specifies a directory that contains files with CRLs in PEM format
7867 to use when verifying S/MIME messages.
7870 .It Va smime-crl-file
7871 \*(OP Specifies a file that contains a CRL in PEM format to use when
7872 verifying S/MIME messages.
7875 .It Va smime-encrypt-USER@HOST
7876 \*(OP If this variable is set, messages send to the given receiver are
7877 encrypted before sending.
7878 The value of the variable must be set to the name of a file that
7879 contains a certificate in PEM format.
7881 If a message is sent to multiple recipients,
7882 each of them for whom a corresponding variable is set will receive an
7883 individually encrypted message;
7884 other recipients will continue to receive the message in plain text
7886 .Va smime-force-encryption
7888 It is recommended to sign encrypted messages, i.e., to also set the
7893 .It Va smime-force-encryption
7894 \*(BO\*(OP Causes \*(UA to refuse sending unencrypted messages.
7897 .It Va smime-no-default-ca
7898 \*(BO\*(OP Don't load default CA locations when verifying S/MIME signed
7903 \*(BO\*(OP S/MIME sign outgoing messages with the user's private key
7904 and include the user's certificate as a MIME attachment.
7905 Signing a message enables a recipient to verify that the sender used
7906 a valid certificate,
7907 that the email addresses in the certificate match those in the message
7908 header and that the message content has not been altered.
7909 It does not change the message text,
7910 and people will be able to read the message as usual.
7912 .Va smime-sign-cert , smime-sign-include-certs
7914 .Va smime-sign-message-digest .
7916 .Mx Va smime-sign-cert
7917 .It Va smime-sign-cert-USER@HOST , smime-sign-cert
7918 \*(OP Points to a file in PEM format.
7919 For the purpose of signing and decryption this file needs to contain the
7920 user's private key as well as his certificate.
7924 is always derived from the value of
7926 (or, if that contains multiple addresses,
7928 For the purpose of encryption the recipient's public encryption key
7929 (certificate) is expected; the command
7931 can be used to save certificates of signed messages (the section
7932 .Sx "Signed and encrypted messages with S/MIME"
7933 gives some details).
7934 This mode of operation is usually driven by the specialized form.
7936 When decrypting messages the account is derived from the recipient
7941 of the message, which are searched for addresses for which such
7943 \*(UA always uses the first address that matches,
7944 so if the same message is sent to more than one of the user's addresses
7945 using different encryption keys, decryption might fail.
7947 .Mx Va smime-sign-include-certs
7948 .It Va smime-sign-include-certs-USER@HOST , smime-sign-include-certs
7949 \*(OP If used, this is supposed to a consist of a comma-separated list
7950 of files, each of which containing a single certificate in PEM format to
7951 be included in the S/MIME message in addition to the
7954 This is most useful for long certificate chains if it is desired to aid
7955 the receiving party's verification process.
7956 Note that top level certificates may also be included in the chain but
7957 don't play a role for verification.
7959 .Va smime-sign-cert .
7960 Remember that for this
7962 refers to the variable
7964 (or, if that contains multiple addresses,
7967 .Mx Va smime-sign-message-digest
7968 .It Va smime-sign-message-digest-USER@HOST , smime-sign-message-digest
7969 \*(OP Specifies the message digest to use when signing S/MIME messages.
7970 RFC 5751 mandates a default of
7972 Possible values are (case-insensitive and) in decreasing cipher strength:
7980 The actually available message digest algorithms depend on the
7981 cryptographic library that \*(UA uses.
7982 \*(OP Support for more message digest algorithms may be available
7983 through dynamic loading via, e.g.,
7984 .Xr EVP_get_digestbyname 3
7985 (OpenSSL) if \*(UA has been compiled to support this.
7986 Remember that for this
7988 refers to the variable
7990 (or, if that contains multiple addresses,
7995 \*(OB\*(OP To use the builtin SMTP transport, specify a SMTP URL in
7997 \*(ID For compatibility reasons a set
7999 is used in preference of
8003 .It Va smtp-auth-USER@HOST , smtp-auth-HOST , smtp-auth
8004 \*(OP Variable chain that controls the SMTP
8006 authentication method, possible values are
8012 as well as the \*(OPal methods
8018 method doesn't need any user credentials,
8020 requires a user name and all other methods require a user name and
8028 .Va smtp-auth-password
8030 .Va smtp-auth-user ) .
8035 .Va smtp-auth-USER@HOST :
8036 may override dependent on sender address in the variable
8039 .It Va smtp-auth-password
8040 \*(OP\*(OU Sets the global fallback password for SMTP authentication.
8041 If the authentication method requires a password, but neither
8042 .Va smtp-auth-password
8044 .Va smtp-auth-password-USER@HOST
8046 \*(UA will ask for a password on the user's terminal.
8048 .It Va smtp-auth-password-USER@HOST
8050 .Va smtp-auth-password
8051 for specific values of sender addresses, dependent upon the variable
8054 .It Va smtp-auth-user
8055 \*(OP\*(OU Sets the global fallback user name for SMTP authentication.
8056 If the authentication method requires a user name, but neither
8059 .Va smtp-auth-user-USER@HOST
8061 \*(UA will ask for a user name on the user's terminal.
8063 .It Va smtp-auth-user-USER@HOST
8066 for specific values of sender addresses, dependent upon the variable
8070 .It Va smtp-hostname
8071 \*(OP\*(IN Normally \*(UA uses the variable
8073 to derive the necessary
8075 information in order to issue a
8082 can be used to use the
8084 from the SMTP account
8091 from the content of this variable (or, if that is the empty string,
8093 or the local hostname as a last resort).
8094 This often allows using an address that is itself valid but hosted by
8095 a provider other than which (in
8097 is about to send the message.
8098 Setting this variable also influences the generated
8101 .Mx Va smtp-use-starttls
8102 .It Va smtp-use-starttls-USER@HOST , smtp-use-starttls-HOST , smtp-use-starttls
8103 \*(BO\*(OP Causes \*(UA to issue a
8105 command to make an SMTP
8107 session SSL/TLS encrypted, i.e., to enable transport layer security.
8111 .It Va spam-interface
8112 \*(OP In order to use any of the spam-related commands (like, e.g.,
8114 the desired spam interface must be defined by setting this variable.
8115 Please refer to the manual section
8117 for the complete picture of spam handling in \*(UA.
8118 All or none of the following interfaces may be available:
8120 .Bl -tag -width ".It Ql _ilte_"
8126 .Pf ( Lk http://spamassassin.apache.org SpamAssassin )
8128 Different to the generic filter interface \*(UA will automatically add
8129 the correct arguments for a given command and has the necessary
8130 knowledge to parse the program's output.
8133 will have been compiled into the \*(UA binary if
8138 Shall it be necessary to define a specific connection type (rather than
8139 using a configuration file for that), the variable
8141 can be used as in, e.g.,
8142 .Ql -d server.example.com -p 783 .
8143 It is also possible to specify a per-user configuration via
8145 Note that this interface doesn't inspect the
8147 flag of a message for the command
8151 generic spam filter support via freely configurable hooks.
8152 This interface is meant for programs like
8154 and requires according behaviour in respect to the hooks' exit
8155 status for at least the command
8158 meaning a message is spam,
8162 for unsure and any other return value indicating a hard error);
8163 since the hooks can include shell code snippets diverting behaviour
8164 can be intercepted as necessary.
8166 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
8169 .Va spamfilter-spam ;
8172 contains examples for some programs.
8173 The process environment of the hooks will have the variables
8174 .Ev NAIL_TMPDIR , TMPDIR
8176 .Ev NAIL_FILENAME_GENERATED
8178 Note that spam score support for
8180 isn't supported unless the \*(OPtional regular expression support is
8182 .Va spamfilter-rate-scanscore
8189 \*(OP Messages that exceed this size won't be passed through to the
8191 .Va spam-interface .
8192 If unset or 0, the default of 420000 bytes is used.
8195 .It Va spamc-command
8196 \*(OP The path to the
8200 .Va spam-interface .
8201 Note that the path is not expanded, but used
8203 A fallback path will have been compiled into the \*(UA binary if the
8204 executable had been found during compilation.
8207 .It Va spamc-arguments
8208 \*(OP Even though \*(UA deals with most arguments for the
8211 automatically, it may at least sometimes be desirable to specify
8212 connection-related ones via this variable, e.g.,
8213 .Ql -d server.example.com -p 783 .
8217 \*(OP Specify a username for per-user configuration files for the
8219 .Va spam-interface .
8220 If this is set to the empty string then \*(UA will use the name of the
8229 .It Va spamfilter-ham , spamfilter-noham , \
8230 spamfilter-nospam , spamfilter-rate , spamfilter-spam
8231 \*(OP Command and argument hooks for the
8233 .Va spam-interface .
8236 contains examples for some programs.
8239 .It Va spamfilter-rate-scanscore
8240 \*(OP Because of the generic nature of the
8243 spam scores are not supported for it by default, but if the \*(OPtional
8244 regular expression support is available then setting this variable can
8245 be used to overcome this restriction.
8246 It is interpreted as follows: first a number (digits) is parsed that
8247 must be followed by a semicolon
8249 and an extended regular expression.
8250 Then the latter is used to parse the first output line of the
8252 hook, and, in case the evaluation is successful, the group that has been
8253 specified via the number is interpreted as a floating point scan score.
8257 \*(OP Specifies a directory with CA certificates in PEM (Pricacy
8258 Enhanced Mail) for verification of of SSL/TLS server certificates.
8260 .Xr SSL_CTX_load_verify_locations 3
8261 for more information.
8265 \*(OP Specifies a file with CA certificates in PEM format for
8266 verification of SSL/TLS server certificates.
8268 .Xr SSL_CTX_load_verify_locations 3
8269 for more information.
8272 .It Va ssl-cert-USER@HOST , ssl-cert-HOST , ssl-cert
8273 \*(OP Variable chain that sets the file name for a SSL/TLS client
8274 certificate required by some servers.
8275 This is a direct interface to the
8279 function of the OpenSSL library, if available.
8281 .Mx Va ssl-cipher-list
8282 .It Va ssl-cipher-list-USER@HOST , ssl-cipher-list-HOST , ssl-cipher-list
8283 \*(OP Specifies a list of ciphers for SSL/TLS connections.
8284 This is a direct interface to the
8288 function of the OpenSSL library, if available; see
8290 for more information.
8291 By default \*(UA doesn't set a list of ciphers, which in effect will use a
8293 specific cipher (protocol standards ship with a list of acceptable
8294 ciphers), possibly cramped to what the actually used SSL/TLS library
8295 supports \(en the manual section
8296 .Sx "An example configuration"
8297 also contains a SSL/TLS use case.
8300 .It Va ssl-config-file
8301 \*(OP If this variable is set \*(UA will call
8302 .Xr CONF_modules_load_file 3
8303 to allow OpenSSL to be configured according to the host system wide
8305 If a non-empty value is given then this will be used to specify the
8306 configuration file to be used instead of the global OpenSSL default;
8307 note that in this case it is an error if the file cannot be loaded.
8308 The application name will always be passed as
8313 \*(OP Specifies a file that contains a CRL in PEM format to use when
8314 verifying SSL/TLS server certificates.
8318 \*(OP Specifies a directory that contains files with CRLs in PEM format
8319 to use when verifying SSL/TLS server certificates.
8322 .It Va ssl-key-USER@HOST , ssl-key-HOST , ssl-key
8323 \*(OP Variable chain that sets the file name for the private key of
8324 a SSL/TLS client certificate.
8325 If unset, the name of the certificate file is used.
8326 The file is expected to be in PEM format.
8327 This is a direct interface to the
8331 function of the OpenSSL library, if available.
8334 .It Va ssl-method-USER@HOST , ssl-method-HOST , ssl-method
8335 \*(OB\*(OP Please use the newer and more flexible
8337 instead: if both values are set,
8339 will take precedence!
8340 Can be set to the following values, the actually used
8342 specification to which it is mapped is shown in parenthesis:
8344 .Pf ( Ql -ALL, TLSv1.2 ) ,
8346 .Pf ( Ql -ALL, TLSv1.1 ) ,
8348 .Pf ( Ql -ALL, TLSv1 )
8351 .Pf ( Ql -ALL, SSLv3 ) ;
8356 and thus includes the SSLv3 protocol.
8357 Note that SSLv2 is no longer supported at all.
8360 .It Va ssl-no-default-ca
8361 \*(BO\*(OP Don't load default CA locations to verify SSL/TLS server
8365 .It Va ssl-protocol-USER@HOST , ssl-protocol-HOST , ssl-protocol
8366 \*(OP Specify the used SSL/TLS protocol.
8367 This is a direct interface to the
8371 function of the OpenSSL library, if available;
8372 otherwise an \*(UA internal parser is used which understands the
8373 following subset of (case-insensitive) command strings:
8379 as well as the special value
8381 Multiple specifications may be given via a comma-separated list which
8382 ignores any whitespace.
8385 plus prefix will enable a protocol, a
8387 minus prefix will disable it, so that
8389 will enable only the TLSv1.2 protocol.
8391 It depends upon the used TLS/SSL library which protocols are actually
8392 supported and which protocols are used if
8394 is not set, but note that SSLv2 is no longer supported at all and
8396 Especially for older protocols explicitly securing
8398 may be worthwile, see
8399 .Sx "An example configuration" .
8403 \*(OP Gives the pathname to an entropy daemon socket, see
8405 Not all SSL/TLS libraries support this.
8408 .It Va ssl-rand-file
8409 \*(OP Gives the filename to a file with random entropy data, see
8410 .Xr RAND_load_file 3 .
8411 If this variable is not set, or set to the empty string, or if the
8412 filename expansion failed, then
8413 .Xr RAND_file_name 3
8414 will be used to create the filename if, and only if,
8416 documents that the SSL PRNG is not yet sufficiently seeded.
8417 If \*(UA successfully seeded the SSL PRNG then it'll update the file via
8418 .Xr RAND_write_file 3 .
8419 This variable is only used if
8421 is not set (or not supported by the SSL/TLS library).
8424 .It Va ssl-verify-USER@HOST , ssl-verify-HOST , ssl-verify
8425 \*(OP Variable chain that sets the action to be performed if an error
8426 occurs during SSL/TLS server certificate validation.
8427 Valid (case-insensitive) values are
8429 (fail and close connection immediately),
8431 (ask whether to continue on standard input),
8433 (show a warning and continue),
8435 (do not perform validation).
8441 If only set without an assigned value, then this option inhibits the
8446 header fields that include obvious references to \*(UA.
8447 There are two pitfalls associated with this:
8448 First, the message id of outgoing messages is not known anymore.
8449 Second, an expert may still use the remaining information in the header
8450 to track down the originating mail user agent.
8455 suppression doesn't occur.
8460 (\*(OP) This specifies a comma-separated list of
8465 .Sx "On terminal control and line editor" ,
8466 escape commas with reverse solidus) to be used to overwrite or define
8468 Note that this variable will only be queried once at program startup and
8469 can thus only be specified in resource files or on the command line.
8472 String capabilities form
8474 pairs and are expected unless noted otherwise.
8475 Numerics have to be notated as
8477 where the number is expected in normal decimal notation.
8478 Finally, booleans don't have any value but indicate a true or false
8479 state simply by being defined or not; this indeed means that \*(UA
8480 doesn't support undefining an existing boolean.
8481 String capability values will undergo some expansions before use:
8482 for one notations like
8485 .Ql control-LETTER ,
8486 and for clarification purposes
8488 can be used to specify
8490 (the control notation
8492 could lead to misreadings when a left bracket follows, which it does for
8493 the standard CSI sequence);
8494 finally three letter octal sequences, as in
8497 To specify that a terminal supports 256-colours, and to define sequences
8498 that home the cursor and produce an audible bell, one might write:
8500 .Bd -literal -offset indent
8501 set termcap='Co#256,home=\eE[H,bel=^G'
8505 The following terminal capabilities are or may be meaningful for the
8506 operation of the builtin line editor or \*(UA in general:
8509 .Bl -tag -compact -width yay
8511 .It Cd colors Ns \0or Cd Co
8513 numeric capability specifying the maximum number of colours.
8514 Note that \*(UA doesn't actually care about the terminal beside that,
8515 but always emits ANSI / ISO 6429 escape sequences.
8518 .It Cd rmcup Ns \0or Cd te Ns \0/ Cd smcup Ns \0or Cd ti
8522 respectively: exit and enter the alternative screen
8524 effectively turning \*(UA into a fullscreen application.
8525 To disable that, set (at least) one to the empty string.
8527 .It Cd smkx Ns \0or Cd ks Ns \0/ Cd rmkx Ns \0or Cd ke
8531 respectively: enable and disable the keypad.
8532 This is always enabled if available, because it seems even keyboards
8533 without keypads generate other key codes for, e.g., cursor keys in that
8534 case, and only if enabled we see the codes that we are interested in.
8536 .It Cd ed Ns \0or Cd cd
8540 .It Cd clear Ns \0or Cd cl
8542 clear the screen and home cursor.
8543 (Will be simulated via
8548 .It Cd home Ns \0or Cd ho
8553 .It Cd el Ns \0or Cd ce
8555 clear to the end of line.
8556 (Will be simulated via
8558 plus repetitions of space characters.)
8560 .It Cd hpa Ns \0or Cd ch
8561 .Cd column_address :
8562 move the cursor (to the given column parameter) in the current row.
8563 (Will be simulated via
8569 .Cd carriage_return :
8570 move to the first column in the current row.
8571 The default builtin fallback is
8574 .It Cd cub1 Ns \0or Cd le
8576 move the cursor left one space (non-destructively).
8577 The default builtin fallback is
8580 .It Cd cuf1 Ns \0or Cd nd
8582 move the cursor right one space (non-destructively).
8583 The default builtin fallback is
8585 which is used by most terminals.
8593 Many more capabilities which describe key-sequences are documented for
8597 .It Va termcap-disable
8598 \*(OP Disable any interaction with a terminal control library.
8599 If set only some generic fallback builtins and possibly the content of
8601 describe the terminal to \*(UA.
8603 that this variable will only be queried once at program startup and can
8604 thus only be specified in resource files or on the command line.
8608 If defined, gives the number of lines of a message to be displayed
8611 if unset, the first five lines are printed, if set to 0 the variable
8614 If the value is negative then its absolute value will be used for right
8617 height; (shifting bitwise is like dividing algorithmically, but since
8618 it takes away bits the value decreases pretty fast).
8622 \*(BO If set then the
8624 command series will strip adjacent empty lines and quotations.
8628 The character set of the terminal \*(UA operates on,
8629 and the one and only supported character set that \*(UA can use if no
8630 character set conversion capabilities have been compiled into it,
8631 in which case it defaults to ISO-8859-1 unless it can deduce a value
8635 Refer to the section
8636 .Sx "Character sets"
8637 for the complete picture about character sets.
8641 For a safety-by-default policy \*(UA sets its process
8645 but this variable can be used to override that:
8646 set it to an empty value to don't change the (current) setting,
8647 otherwise the process file mode creation mask is updated to the new value.
8648 Child processes inherit the process file mode creation mask.
8651 .It Va user-HOST , user
8652 \*(IN Variable chain that sets a global fallback user name, which is
8653 used in case none has been given in the protocol and account-specific
8655 This variable defaults to the name of the user who runs \*(UA.
8659 \*(BO Setting this option enables upward compatibility with \*(UA
8660 version 15.0 in respect to which configuration options are available and
8661 how they are handled.
8662 This manual uses \*(IN and \*(OU to refer to the new and the old way of
8663 doing things, respectively.
8667 \*(BO Setting this option, also controllable via the command line option
8669 causes \*(UA to be more verbose, e.g., it will display obsoletion
8670 warnings and SSL/TLS certificate chains.
8671 Even though marked \*(BO this option may be set twice in order to
8672 increase the level of verbosity even more, in which case even details of
8673 the actual message delivery and protocol conversations are shown.
8676 is sufficient to disable verbosity as such.
8682 .It Va version , version-major , version-minor , version-update
8683 \*(RO \*(UA version information: the first variable contains a string
8684 containing the complete version identification, the latter three contain
8685 only digits: the major, minor and update version numbers.
8686 The output of the command
8688 will include this information.
8691 .It Va writebackedited
8692 If this variable is set messages modified using the
8696 commands are written back to the current folder when it is quit;
8697 it is only honoured for writable folders in MBOX format, though.
8698 Note that the editor will be pointed to the raw message content in that
8699 case, i.e., neither MIME decoding nor decryption will have been
8700 performed, and proper RFC 4155
8702 quoting of newly added or edited content is also left as an excercise to
8706 .\" }}} (INTERNAL VARIABLES)
8709 .\" .Sh ENVIRONMENT {{{
8713 .Dq environment variable
8714 should be considered an indication that these variables are either
8715 standardized as vivid parts of process environments, or that they are
8716 commonly found in there.
8717 The process environment is inherited from the
8719 once \*(UA is started, and unless otherwise explicitly noted handling of
8720 the following variables transparently integrates into that of the
8721 .Sx "INTERNAL VARIABLES"
8722 from \*(UA's point of view.
8723 This means that, e.g., they can be managed via
8727 causing automatic program environment updates (to be inherited by
8728 newly created child processes).
8731 In order to transparently integrate other environment variables equally
8732 they need to be imported (linked) with the command
8734 This command can also be used to set and unset non-integrated
8735 environment variables from scratch, sufficient system support provided.
8736 The following example, applicable to a POSIX shell, sets the
8738 environment variable for \*(UA only, and beforehand exports the
8740 in order to affect any further processing in the running shell:
8742 .Bd -literal -offset indent
8743 $ EDITOR="vim -u ${HOME}/.vimrc"
8745 $ COLUMNS=80 \*(uA -R
8748 .Bl -tag -width ".It Ev _AILR_"
8751 The user's preferred width in column positions for the terminal screen
8753 Queried and used once on program startup, actively managed for child
8754 processes and the MLE (see
8755 .Sx "On terminal control and line editor" )
8756 in interactive mode thereafter.
8760 The name of the (mailbox)
8762 to use for saving aborted messages if
8764 is set; this defaults to
8771 is set no output will be generated, otherwise the contents of the file
8776 Pathname of the text editor to use in the
8780 .Sx "TILDE ESCAPES" .
8781 A default editor is used if this value is not defined.
8785 The user's home directory.
8786 This variable is only used when it resides in the process environment.
8793 .It Ev LANG , LC_ALL , LC_COLLATE , LC_CTYPE , LC_MESSAGES
8797 .Sx "Character sets" .
8801 The user's preferred number of lines on a page or the vertical screen
8802 or window size in lines.
8803 Queried and used once on program startup, actively managed for child
8804 processes in interactive mode thereafter.
8808 Pathname of the directory lister to use in the
8810 command when operating on local mailboxes.
8813 (path search through
8818 Upon startup \*(UA will actively ensure that this variable refers to the
8819 name of the user who runs \*(UA, in order to be able to pass a verified
8820 name to any newly created child process.
8824 Is used as the user's primary system mailbox, if set.
8825 Otherwise, a system-dependent default is used.
8826 Supports the special syntax conventions that are documented for the
8832 \*(OP Overrides the default path search for
8833 .Sx "The Mailcap files" ,
8834 which is defined in the standard RFC 1524 as
8835 .Ql ~/.mailcap:\:/etc/mailcap:\:/usr/etc/mailcap:\:/usr/local/etc/mailcap .
8836 .\" TODO we should have a mailcaps-default virtual RDONLY option!
8837 (\*(UA makes it a configuration option, however.)
8838 Note this is not a search path, but a path search.
8842 Is used as a startup file instead of
8845 When \*(UA scripts are invoked on behalf of other users,
8846 either this variable should be set to
8850 command line option should be used in order to avoid side-effects from
8851 reading their configuration files.
8852 This variable is only used when it resides in the process environment.
8856 The name of the user's mbox file.
8857 A logical subset of the special conventions that are documented for the
8862 The fallback default is
8867 Traditionally this secondary mailbox is used as the file to save
8868 messages from the primary system mailbox that have been read.
8870 .Sx "Message states" .
8873 .It Ev NAIL_NO_SYSTEM_RC
8874 If this variable is set then reading of
8876 at startup is inhibited, i.e., the same effect is achieved as if \*(UA
8877 had been started up with the option
8879 This variable is only used when it resides in the process environment.
8883 \*(IN\*(OP This variable overrides the default location of the user's
8889 Pathname of the program to use for backing the command
8893 variable enforces usage of a pager for output.
8894 The default paginator is
8896 (path search through
8899 \*(UA inspects the contents of this variable: if its contains the string
8901 then a non-existing environment variable
8908 dependent on whether terminal control support is available and whether
8909 that supports full (alternative) screen mode or not (also see
8910 .Sx "On terminal control and line editor" ) .
8914 will optionally be set to
8921 A colon-separated list of directories that is searched by the shell when
8922 looking for commands, e.g.,
8923 .Ql /bin:/usr/bin:/usr/local/bin .
8927 The shell to use for the commands
8933 and when starting subprocesses.
8934 A default shell is used if this option is not defined.
8937 .It Ev SOURCE_DATE_EPOCH
8938 If set, this specifies a time in seconds since the Unix epoch
8939 (1970-01-01) to be used in place of the current time.
8940 This is for the sake of reproduceability of tests, to be used during
8941 development or by software packagers.
8945 \*(OP The terminal type for which output is to be prepared.
8946 For extended colour and font control please refer to
8947 .Sx "Coloured display" ,
8948 and for terminal management in general to
8949 .Sx "On terminal control and line editor" .
8953 Used as directory for temporary files instead of
8956 This variable is only used when it resides in the process environment.
8962 (see there), but this variable is not standardized, should therefore not
8963 be used, and is only corrected if already set.
8967 Pathname of the text editor to use in the
8971 .Sx "TILDE ESCAPES" .
8979 .Bl -tag -width ".It Pa _etc/mime.type_"
8981 File giving initial commands.
8984 System wide initialization file.
8988 \*(OP Personal MIME type handler definition file, see
8989 .Sx "The Mailcap files" .
8990 (RFC 1524 location, the actual path is a configuration option.)
8994 \*(OP System wide MIME type handler definition file, see
8995 .Sx "The Mailcap files" .
8996 (RFC 1524 location, the actual path is a configuration option.)
8999 .It Pa ~/.mime.types
9000 Personal MIME types, see
9001 .Sx "The mime.types files" .
9004 .It Pa /etc/mime.types
9005 System wide MIME types, see
9006 .Sx "The mime.types files" .
9010 \*(IN\*(OP The default location of the users
9012 file \(en the section
9013 .Sx "The .netrc file"
9014 documents the file format.
9017 .\" .Ss "The mime.types files" {{{
9018 .Ss "The mime.types files"
9020 When sending messages \*(UA tries to determine the content type of all
9022 When displaying message content or attachments \*(UA uses the content
9023 type to decide whether it can directly display data or whether it needs
9024 to deal with content handlers.
9025 It learns about MIME types and how to treat them by reading
9027 files, the loading of which can be controlled by setting the variable
9028 .Va mimetypes-load-control .
9031 can also be used to deal with MIME types.)
9033 files have the following syntax:
9036 .Dl type/subtype extension [extension ...]
9041 are strings describing the file contents, and one or multiple
9043 s, separated by whitespace, name the part of a filename starting after
9044 the last dot (of interest).
9045 Comments may be introduced anywhere on a line with a number sign
9047 causing the remaining line to be discarded.
9049 \*(UA also supports an extended, non-portable syntax in specially
9050 crafted files, which can be loaded via the alternative value syntax of
9051 .Va mimetypes-load-control
9052 and prepends an optional
9056 .Dl [type-marker ]type/subtype extension [extension ...]
9059 The following type markers are supported:
9062 .Bl -tag -compact -offset indent -width ".It Ar _n_u"
9064 Treat message parts with this content as plain text.
9069 Treat message parts with this content as HTML tagsoup.
9070 If the \*(OPal HTML-tagsoup-to-text converter is not available treat
9071 the content as plain text instead.
9075 but instead of falling back to plain text require an explicit content
9076 handler to be defined.
9081 for sending messages:
9083 .Va mime-allow-text-controls ,
9084 .Va mimetypes-load-control .
9085 For reading etc. messages:
9086 .Sx "HTML mail and MIME attachments" ,
9087 .Sx "The Mailcap files" ,
9089 .Va mime-counter-evidence ,
9090 .Va mimetypes-load-control ,
9091 .Va pipe-TYPE/SUBTYPE ,
9092 .Va pipe-EXTENSION .
9095 .\" .Ss "The Mailcap files" {{{
9096 .Ss "The Mailcap files"
9099 .Dq User Agent Configuration Mechanism
9100 which \*(UA \*(OPally supports.
9101 It defines a file format to be used to inform mail user agent programs
9102 about the locally-installed facilities for handling various data
9103 formats, i.e., about commands and how they can be used to display, edit
9104 etc. MIME part contents, as well as a default path search that includes
9105 multiple possible locations of
9109 environment variable that can be used to overwrite that (repeating here
9110 that it is not a search path, but instead a path search specification).
9111 Any existing files will be loaded in sequence, appending any content to
9112 the list of MIME type handler directives.
9116 files consist of a set of newline separated entries.
9117 Comment lines start with a number sign
9119 (in the first column!) and are ignored.
9120 Empty lines are also ignored.
9121 All other lines form individual entries that must adhere to the syntax
9123 To extend a single entry (not comment) its line can be continued on
9124 follow lines if newline characters are
9126 by preceding them with the reverse solidus character
9128 The standard doesn't specify how leading whitespace of follow lines is
9129 to be treated, therefore \*(UA retains it.
9133 entries consist of a number of semicolon
9135 separated fields, and the reverse solidus
9137 character can be used to escape any following character including
9138 semicolon and itself.
9139 The first two fields are mandatory and must occur in the specified
9140 order, the remaining fields are optional and may appear in any order.
9141 Leading and trailing whitespace of content is ignored (removed).
9144 The first field defines the MIME
9146 the entry is about to handle (case-insensitively, and no reverse solidus
9147 escaping is possible in this field).
9148 If the subtype is specified as an asterisk
9150 the entry is meant to match all subtypes of the named type, e.g.,
9152 would match any audio type.
9153 The second field defines the shell command which shall be used to
9155 MIME parts of the given type; it is implicitly called the
9162 shell commands message (MIME part) data is passed via standard input
9163 unless the given shell command includes one or more instances of the
9166 in which case these instances will be replaced with a temporary filename
9167 and the data will have been stored in the file that is being pointed to.
9170 shell commands data is assumed to be generated on standard output unless
9171 the given command includes (one ore multiple)
9173 In any case any given
9175 format is replaced with a(n already) properly quoted filename.
9176 Note that when a command makes use of a temporary file via
9178 then \*(UA will remove it again, as if the
9179 .Cd x-mailx-tmpfile ,
9180 .Cd x-mailx-tmpfile-fill
9182 .Cd x-mailx-tmpfile-unlink
9183 flags had been set; see below for more.
9186 The optional fields either define a shell command or an attribute (flag)
9187 value, the latter being a single word and the former being a keyword
9188 naming the field followed by an equals sign
9190 succeeded by a shell command, and as usual for any
9192 content any whitespace surrounding the equals sign will be removed, too.
9193 Optional fields include the following:
9196 .Bl -tag -width textualnewlines
9198 A program that can be used to compose a new body or body part in the
9205 field, but is to be used when the composing program needs to specify the
9207 header field to be applied to the composed data.
9211 A program that can be used to edit a body or body part in the given
9216 A program that can be used to print a message or body part in the given
9221 Specifies a program to be run to test some condition, e.g., the machine
9222 architecture, or the window system in use, to determine whether or not
9223 this mailcap entry applies.
9224 If the test fails, a subsequent mailcap entry should be sought; also see
9225 .Cd x-mailx-test-once .
9227 .It Cd needsterminal
9228 This flag field indicates that the given shell command must be run on
9229 an interactive terminal.
9230 \*(UA will temporarily release the terminal to the given command in
9231 interactive mode, in non-interactive mode this entry will be entirely
9232 ignored; this flag implies
9233 .Cd x-mailx-noquote .
9235 .It Cd copiousoutput
9236 A flag field which indicates that the output of the
9238 command will be an extended stream of textual output that can be
9239 (re)integrated into \*(UA's normal visual display.
9240 It is mutually exclusive with
9243 .Cd x-mailx-always .
9245 .It Cd textualnewlines
9246 A flag field which indicates that this type of data is line-oriented and
9249 all newlines should be converted to canonical form (CRLF) before
9250 encoding, and will be in that form after decoding.
9254 This field gives a file name format, in which
9256 will be replaced by a random string, the joined combination of which
9257 will be used as the filename denoted by
9258 .Ev NAIL_FILENAME_TEMPORARY .
9259 One could specify that a GIF file being passed to an image viewer should
9260 have a name ending in
9263 .Ql nametemplate=%s.gif .
9264 Note that \*(UA ignores the name template unless that solely specifies
9265 a filename suffix that consists of (ASCII) alphabetic and numeric
9266 characters, the underscore and dot only.
9269 Names a file, in X11 bitmap (xbm) format, which points to an appropriate
9270 icon to be used to visually denote the presence of this kind of data.
9271 This field is not used by \*(UA.
9274 A textual description that describes this type of data.
9276 .It Cd x-mailx-always
9277 Extension flag field that denotes that the given
9279 command shall be executed even if multiple messages will be displayed
9281 Normally messages which require external viewers that produce output
9282 which doesn't integrate into \*(UA's visual display (i.e., don't have
9284 set) have to be addressed directly and individually.
9285 (To avoid cases where, e.g., a thousand PDF viewer instances are spawned
9288 .It Cd x-mailx-even-if-not-interactive
9289 An extension flag test field \(em by default handlers without
9291 are entirely ignored in non-interactive mode, but if this flag is set
9292 then their use will be considered.
9293 It is an error if this flag is set for commands that use the flag
9296 .It Cd x-mailx-noquote
9297 An extension flag field that indicates that even a
9300 command shall not be used to generate message quotes
9301 (as it would be by default).
9303 .It Cd x-mailx-async
9304 Extension flag field that denotes that the given
9306 command shall be executed asynchronously, without blocking \*(UA.
9307 Cannot be used in conjunction with
9310 .It Cd x-mailx-test-once
9311 Extension flag which denotes whether the given
9313 command shall be evaluated once only and the (boolean) result be cached.
9314 This is handy if some global unchanging condition is to be queried, like
9315 .Dq running under the X Window System .
9317 .It Cd x-mailx-tmpfile
9318 Extension flag field that requests creation of a zero-sized temporary
9319 file, the name of which is to be placed in the environment variable
9320 .Ev NAIL_FILENAME_TEMPORARY .
9321 It is an error to use this flag with commands that include a
9325 .It Cd x-mailx-tmpfile-fill
9326 Normally the MIME part content is passed to the handler via standard
9327 input; if this flag is set then the data will instead be written into
9329 .Cd x-mailx-tmpfile .
9330 In order to cause deletion of the temporary file you will have to set
9331 .Cd x-mailx-tmpfile-unlink
9333 It is an error to use this flag with commands that include a
9337 .It Cd x-mailx-tmpfile-unlink
9338 Extension flag field that requests that the temporary file shall be
9339 deleted automatically when the command loop is entered again at latest.
9340 (Don't use this for asynchronous handlers.)
9341 It is an error to use this flag with commands that include a
9343 format, or without also setting
9346 .Cd x-mailx-tmpfile-fill .
9348 .It Cd x-mailx-tmpfile-keep
9351 implies the three tmpfile related flags above, but if you want, e.g.,
9353 and deal with the temporary file yourself, you can add in this flag to
9355 .Cd x-mailx-tmpfile-unlink .
9360 The standard includes the possibility to define any number of additional
9361 entry fields, prefixed by
9363 Flag fields apply to the entire
9365 entry \(em in some unusual cases, this may not be desirable, but
9366 differentiation can be accomplished via separate entries, taking
9367 advantage of the fact that subsequent entries are searched if an earlier
9368 one does not provide enough information.
9371 command needs to specify the
9375 command shall not, the following will help out the latter (with enabled
9379 level \*(UA will show information about handler evaluation):
9381 .Bd -literal -offset indent
9382 application/postscript; ps-to-terminal %s; needsterminal
9383 application/postscript; ps-to-terminal %s; compose=idraw %s
9387 In fields any occurrence of the format string
9389 will be replaced by the
9392 Named parameters from the
9394 field may be placed in the command execution line using
9396 followed by the parameter name and a closing
9399 The entire parameter should appear as a single command line argument,
9400 regardless of embedded spaces; thus:
9402 .Bd -literal -offset indent
9404 Content-type: multipart/mixed; boundary=42
9407 multipart/*; /usr/local/bin/showmulti \e
9408 %t %{boundary} ; composetyped = /usr/local/bin/makemulti
9410 # Executed shell command
9411 /usr/local/bin/showmulti multipart/mixed 42
9415 .\" TODO v15: Mailcap: %n,%F
9416 Note that \*(UA doesn't support handlers for multipart MIME parts as
9417 shown in this example (as of today).
9418 \*(UA doesn't support the additional formats
9422 An example file, also showing how to properly deal with the expansion of
9424 which includes any quotes that are necessary to make it a valid shell
9425 argument by itself and thus will cause undesired behaviour when placed
9426 in additional user-provided quotes:
9428 .Bd -literal -offset indent
9430 text/richtext; richtext %s; copiousoutput
9432 text/x-perl; perl -cWT %s
9436 trap "rm -f ${infile}" EXIT\e; \e
9437 trap "exit 75" INT QUIT TERM\e; \e
9439 x-mailx-async; x-mailx-tmpfile-keep
9441 application/*; echo "This is \e"%t\e" but \e
9442 is 50 \e% Greek to me" \e; < %s head -c 1024 | cat -vET; \e
9443 copiousoutput; x-mailx-noquote
9448 .Sx "HTML mail and MIME attachments" ,
9449 .Sx "The mime.types files" ,
9452 .Va mime-counter-evidence ,
9453 .Va pipe-TYPE/SUBTYPE ,
9454 .Va pipe-EXTENSION .
9457 .\" .Ss "The .netrc file" {{{
9458 .Ss "The .netrc file"
9462 file contains user credentials for machine accounts.
9463 The default location in the user's
9465 directory may be overridden by the
9467 environment variable.
9468 The file consists of space, tabulator or newline separated tokens.
9469 \*(UA implements a parser that supports a superset of the original BSD
9470 syntax, but users should nonetheless be aware of portability glitches
9471 of that file format, shall their
9473 be usable across multiple programs and platforms:
9476 .Bl -bullet -compact
9478 BSD doesn't support single, but only double quotation marks, e.g.,
9479 .Ql password="pass with spaces" .
9481 BSD (only?) supports escaping of single characters via a reverse solidus
9482 (e.g., a space can be escaped via
9484 in- as well as outside of a quoted string.
9486 BSD doesn't require the final quotation mark of the final user input token.
9488 The original BSD (Berknet) parser also supported a format which allowed
9489 tokens to be separated with commas \(en whereas at least Hewlett-Packard
9490 still seems to support this syntax, \*(UA does not!
9492 As a non-portable extension some widely-used programs support
9493 shell-style comments: if an input line starts, after any amount of
9494 whitespace, with a number sign
9496 then the rest of the line is ignored.
9498 Whereas other programs may require that the
9500 file is accessible by only the user if it contains a
9506 \*(UA will always require these strict permissions.
9510 Of the following list of supported tokens \*(UA only uses (and caches)
9515 At runtime the command
9517 can be used to control \*(UA's
9521 .Bl -tag -width password
9522 .It Cd machine Ar name
9523 The hostname of the entries' machine, lowercase-normalized by \*(UA
9525 Any further file content, until either end-of-file or the occurrence
9530 first-class token is bound (only related) to the machine
9533 As an extension that shouldn't be the cause of any worries
9534 \*(UA supports a single wildcard prefix for
9536 .Bd -literal -offset indent
9537 machine *.example.com login USER password PASS
9538 machine pop3.example.com login USER password PASS
9539 machine smtp.example.com login USER password PASS
9545 .Ql pop3.example.com ,
9549 .Ql local.smtp.example.com .
9550 Note that in the example neither
9551 .Ql pop3.example.com
9553 .Ql smtp.example.com
9554 will be matched by the wildcard, since the exact matches take
9555 precedence (it is however faster to specify it the other way around).
9560 except that it is a fallback entry that is used shall none of the
9561 specified machines match; only one default token may be specified,
9562 and it must be the last first-class token.
9564 .It Cd login Ar name
9565 The user name on the remote machine.
9567 .It Cd password Ar string
9568 The user's password on the remote machine.
9570 .It Cd account Ar string
9571 Supply an additional account password.
9572 This is merely for FTP purposes.
9574 .It Cd macdef Ar name
9576 A macro is defined with the specified
9578 it is formed from all lines beginning with the next line and continuing
9579 until a blank line is (consecutive newline characters are) encountered.
9582 entries cannot be utilized by multiple machines, too, but must be
9583 defined following the
9585 they are intended to be used with.)
9588 exists, it is automatically run as the last step of the login process.
9589 This is merely for FTP purposes.
9596 .\" .Sh EXAMPLES {{{
9599 .\" .Ss "An example configuration" {{{
9600 .Ss "An example configuration"
9602 .Bd -literal -offset indent
9603 # This example assumes v15.0 compatibility mode
9606 # Where are the up-to-date SSL certificates?
9607 #set ssl-ca-dir=/etc/ssl/certs
9608 set ssl-ca-file=/etc/ssl/certs/ca-certificates.crt
9610 # (Since we manage up-to-date ones explicitly, don't use any,
9611 # possibly outdated, default certificates shipped with OpenSSL)
9612 set ssl-no-default-ca
9614 # Don't use protocols older than TLS v1.2.
9615 # Change this only when the remote server doesn't support it:
9616 # maybe use ssl-protocol-HOST (or -USER@HOST) syntax to define
9617 # such explicit exceptions, then
9618 set ssl-protocol='-ALL,+TLSv1.2'
9620 # Explicitly define the list of ciphers, which may improve security,
9621 # especially with protocols older than TLS v1.2. See ciphers(1).
9622 # Including "@STRENGTH" will sort the final list by algorithm strength.
9623 # In reality it is possibly best to only use ssl-cipher-list-HOST
9624 # (or -USER@HOST), as necessary, again..
9625 set ssl-cipher-list=TLSv1.2:!aNULL:!eNULL:!MEDIUM:!LOW:!EXPORT:@STRENGTH
9626 # ALL:!aNULL:!MEDIUM:!LOW:!MD5:!RC4:!EXPORT:@STRENGTH
9628 # Request strict transport security checks!
9629 set ssl-verify=strict
9631 # Essential setting: select allowed character sets
9632 set sendcharsets=utf-8,iso-8859-1
9634 # A very kind option: when replying to a message, first try to
9635 # use the same encoding that the original poster used herself!
9636 set reply-in-same-charset
9638 # When replying to or forwarding a message the comment and name
9639 # parts of email addresses are removed unless this variable is set
9642 # When sending messages, wait until the Mail-Transfer-Agent finishs.
9643 # Only like this you'll be able to see errors reported through the
9644 # exit status of the MTA (including the builtin SMTP one)!
9647 # Only use builtin MIME types, no mime.types(5) files
9648 set mimetypes-load-control
9650 # Default directory where we act in (relative to $HOME)
9652 # A leading "+" (often) means: under *folder*
9653 # *record* is used to save copies of sent messages
9654 set MBOX=+mbox.mbox record=+sent.mbox DEAD=+dead.txt
9656 # Make "file mymbox" and "file myrec" go to..
9657 shortcut mymbox %:+mbox.mbox myrec +sent.mbox
9659 # Not really optional, e.g., for S/MIME
9660 set from='Your Name <address@exam.ple>'
9662 # It may be necessary to set hostname and/or smtp-hostname
9663 # if the "SERVER" of mta and "domain" of from don't match.
9664 # The `urlencode' command can be used to encode USER and PASS
9665 set mta=(smtps?|submission)://[USER[:PASS]@]SERVER[:PORT] \e
9666 smtp-auth=login/plain... \e
9669 # Never refuse to start into interactive mode, and more
9671 colour-pager crt= \e
9672 followup-to followup-to-honour=ask-yes \e
9673 history-file=+.\*(uAhist history-size=-1 history-gabby \e
9674 mime-counter-evidence=0xE \e
9675 prompt='?\e?[\e$ \e@]\e& ' \e
9676 reply-to-honour=ask-yes \e
9679 # When `t'yping messages, show only these headers
9680 # (use `T'ype for all headers and `S'how for raw message)
9681 retain date from to cc subject
9683 # Some mailing lists
9684 mlist '@xyz-editor\e.xyz$' '@xyzf\e.xyz$'
9685 mlsubscribe '^xfans@xfans\e.xyz$'
9687 # A real life example of a very huge free mail provider
9689 set folder=~/spool/XooglX MAIL=+syste.mbox sent=+sent
9690 set from='Your Name <address@examp.ple>'
9691 set mta=smtp://USER:PASS@smtp.gmXil.com smtp-use-starttls
9694 # Here is a pretty large one which does not allow sending mails
9695 # if there is a domain name mismatch on the SMTP protocol level,
9696 # which would bite us if the value of from does not match, e.g.,
9697 # for people who have a sXXXXeforge project and want to speak
9698 # with the mailing list under their project account (in from),
9699 # still sending the message through their normal mail provider
9701 set folder=~/spool/XandeX MAIL=+syste.mbox sent=+sent
9702 set from='Your Name <address@exam.ple>'
9703 set mta=smtps://USER:PASS@smtp.yaXXex.ru:465 \e
9704 hostname=yaXXex.com smtp-hostname=
9707 # Create some new commands so that, e.g., `ls /tmp' will..
9708 wysh ghost lls '!ls ${LS_COLOR_FLAG} -aFlrS'
9709 wysh ghost llS '!ls ${LS_COLOR_FLAG} -aFlS'
9710 wysh ghost ls '!ls ${LS_COLOR_FLAG} -aFrS'
9711 wysh ghost lS '!ls ${LS_COLOR_FLAG} -aFS'
9712 wysh ghost lla '!ls ${LS_COLOR_FLAG} -aFlr'
9713 wysh ghost llA '!ls ${LS_COLOR_FLAG} -aFl'
9714 wysh ghost la '!ls ${LS_COLOR_FLAG} -aFr'
9715 wysh ghost lA '!ls ${LS_COLOR_FLAG} -aF'
9716 wysh ghost ll '!ls ${LS_COLOR_FLAG} -aFltr'
9717 wysh ghost lL '!ls ${LS_COLOR_FLAG} -aFlt'
9718 wysh ghost l '!ls ${LS_COLOR_FLAG} -aFtr'
9719 wysh ghost L '!ls ${LS_COLOR_FLAG} -aFt'
9721 # We don't support gpg(1) directly yet. But simple --clearsign'd
9722 # message parts can be dealt with as follows:
9724 wysh set pipe-text/plain=$'@*#++=@\e
9725 < "${NAIL_FILENAME_TEMPORARY}" awk \e
9726 -v TMPFILE="${NAIL_FILENAME_TEMPORARY}" \e'\e
9728 /^-----BEGIN PGP SIGNED MESSAGE-----/,/^$/{\e
9731 print "--- GPG --verify ---";\e
9732 system("gpg --verify " TMPFILE " 2>&1");\e
9733 print "--- GPG --verify ---";\e
9737 /^-----BEGIN PGP SIGNATURE-----/,\e
9738 /^-----END PGP SIGNATURE-----/{\e
9748 !printf 'Key IDs to gpg --recv-keys: ';\e
9750 gpg --recv-keys ${keyids};
9756 When storing passwords in
9758 appropriate permissions should be set on this file with
9759 .Ql $ chmod 0600 \*(ur .
9762 is available user credentials can be stored in the central
9764 file instead; e.g., here is a different version of the example account
9765 that sets up SMTP and POP3:
9767 .Bd -literal -offset indent
9769 set folder=~/spool/XandeX MAIL=+syste.mbox sent=+sent
9770 set from='Your Name <address@exam.ple>'
9772 # Load an encrypted ~/.netrc by uncommenting the next line
9773 #set netrc-pipe='gpg -qd ~/.netrc.pgp'
9775 set mta=smtps://smtp.yXXXXx.ru:465 \e
9776 smtp-hostname= hostname=yXXXXx.com
9777 set pop3-keepalive=240 pop3-no-apop-pop.yXXXXx.ru
9778 ghost xp fi pop3s://pop.yXXXXx.ru
9787 .Bd -literal -offset indent
9788 machine *.yXXXXx.ru login USER password PASS
9792 This configuration should now work just fine:
9795 .Dl $ echo text | \*(uA -vv -AXandeX -s Subject user@exam.ple
9798 .\" .Ss "Signed and encrypted messages with S/MIME" {{{
9799 .Ss "Signed and encrypted messages with S/MIME"
9801 \*(OP S/MIME provides two central mechanisms:
9802 message signing and message encryption.
9803 A signed message contains some data in addition to the regular text.
9804 The data can be used to verify that the message was sent using a valid
9805 certificate, that the sender's address in the message header matches
9806 that in the certificate, and that the message text has not been altered.
9807 Signing a message does not change its regular text;
9808 it can be read regardless of whether the recipient's software is able to
9812 It is thus usually possible to sign all outgoing messages if so desired.
9813 Encryption, in contrast, makes the message text invisible for all people
9814 except those who have access to the secret decryption key.
9815 To encrypt a message, the specific recipient's public encryption key
9817 It is therefore not possible to send encrypted mail to people unless their
9818 key has been retrieved from either previous communication or public key
9820 A message should always be signed before it is encrypted.
9821 Otherwise, it is still possible that the encrypted message text is
9825 A central concept to S/MIME is that of the certification authority (CA).
9826 A CA is a trusted institution that issues certificates.
9827 For each of these certificates it can be verified that it really
9828 originates from the CA, provided that the CA's own certificate is
9830 A set of CA certificates is usually delivered with OpenSSL and installed
9832 If you trust the source of your OpenSSL software installation,
9833 this offers reasonable security for S/MIME on the Internet.
9835 .Va ssl-no-default-ca
9839 .Va smime-ca-dir . )
9840 In general, a certificate cannot be more secure than the method its CA
9841 certificate has been retrieved with, though.
9842 Thus if you download a CA certificate from the Internet,
9843 you can only trust the messages you verify using that certificate as
9844 much as you trust the download process.
9847 The first thing you need for participating in S/MIME message exchange is
9848 your personal certificate, including a private key.
9849 The certificate contains public information, in particular your name and
9850 your email address(es), and the public key that is used by others to
9851 encrypt messages for you,
9852 and to verify signed messages they supposedly received from you.
9853 The certificate is included in each signed message you send.
9854 The private key must be kept secret.
9855 It is used to decrypt messages that were previously encrypted with your
9856 public key, and to sign messages.
9859 For personal use it is recommended that you get a S/MIME certificate
9860 from one of the major CAs on the Internet using your WWW browser.
9861 Many CAs offer such certificates for free.
9863 .Lk https://www.CAcert.org
9864 which issues client and server certificates to members of their
9865 community for free; their root certificate
9866 .Pf ( Lk https://\:www.cacert.org/\:certs/\:root.crt )
9867 is often not in the default set of trusted CA root certificates, though,
9868 which means you will have to download their root certificate separately
9869 and ensure it is part of our S/MIME certificate validation chain by
9872 or as a vivid member of the
9874 But let's take a step-by-step tour on how to setup S/MIME with
9875 a certificate from CAcert.org despite this situation!
9878 First of all you will have to become a member of the CAcert.org
9879 community, simply by registrating yourself via the web interface.
9880 Once you are, create and verify all email addresses you want to be able
9881 to create signed and encrypted messages for/with using the corresponding
9882 entries of the web interface.
9883 Now ready to create S/MIME certificates, so let's create a new
9884 .Dq client certificate ,
9885 ensure to include all email addresses that should be covered by the
9886 certificate in the following web form, and also to use your name as the
9890 Create a private key and a certificate request on your local computer
9891 (please see the manual pages of the used commands for more in-depth
9892 knowledge on what the used arguments etc. do):
9895 .Dl openssl req -nodes -newkey rsa:4096 -keyout key.pem -out creq.pem
9898 Afterwards copy-and-paste the content of
9900 into the certificate-request (CSR) field of the web form on the
9901 CAcert.org website (you may need to unfold some
9902 .Dq advanced options
9903 to see the corresponding text field).
9904 This last step will ensure that your private key (which never left your
9905 box) and the certificate belong together (through the public key that
9906 will find its way into the certificate via the certificate-request).
9907 You are now ready and can create your CAcert certified certificate.
9908 Download and store or copy-and-paste it as
9913 In order to use your new S/MIME setup you will have to create
9914 a combined private key/public key (certificate) file:
9917 .Dl cat key.pem pub.crt > ME@HERE.com.paired
9920 This is the file \*(UA will work with.
9921 If you have created your private key with a passphrase then \*(UA will
9922 ask you for it whenever a message is signed or decrypted.
9923 Set the following variables to henceforth use S/MIME (setting
9925 is of interest for verification only):
9927 .Bd -literal -offset indent
9928 set smime-ca-file=ALL-TRUSTED-ROOT-CERTS-HERE \e
9929 smime-sign-cert=ME@HERE.com.paired \e
9930 smime-sign-message-digest=SHA256 \e
9935 From each signed message you send, the recipient can fetch your
9936 certificate and use it to send encrypted mail back to you.
9937 Accordingly if somebody sends you a signed message, you can do the same,
9940 command to check the validity of the certificate.
9943 Variables of interest for S/MIME signing:
9947 .Va smime-crl-file ,
9948 .Va smime-no-default-ca ,
9950 .Va smime-sign-cert ,
9951 .Va smime-sign-include-certs
9953 .Va smime-sign-message-digest .
9956 After it has been verified save the certificate via
9958 and tell \*(UA that it should use it for encryption for further
9959 communication with that somebody:
9961 .Bd -literal -offset indent
9963 set smime-encrypt-USER@HOST=FILENAME \e
9964 smime-cipher-USER@HOST=AES256
9968 Additional variables of interest for S/MIME en- and decryption:
9971 .Va smime-encrypt-USER@HOST .
9974 You should carefully consider if you prefer to store encrypted messages
9976 If you do, anybody who has access to your mail folders can read them,
9977 but if you do not, you might be unable to read them yourself later if
9978 you happen to lose your private key.
9981 command saves messages in decrypted form, while the
9985 commands leave them encrypted.
9988 Note that neither S/MIME signing nor encryption applies to message
9989 subjects or other header fields yet.
9990 Thus they may not contain sensitive information for encrypted messages,
9991 and cannot be trusted even if the message content has been verified.
9992 When sending signed messages,
9993 it is recommended to repeat any important header information in the
9997 .\" .Ss "Using CRLs with S/MIME or SSL/TLS" {{{
9998 .Ss "Using CRLs with S/MIME or SSL/TLS"
10000 \*(OP Certification authorities (CAs) issue certificate revocation
10001 lists (CRLs) on a regular basis.
10002 These lists contain the serial numbers of certificates that have been
10003 declared invalid after they have been issued.
10004 Such usually happens because the private key for the certificate has
10006 because the owner of the certificate has left the organization that is
10007 mentioned in the certificate, etc.
10008 To seriously use S/MIME or SSL/TLS verification,
10009 an up-to-date CRL is required for each trusted CA.
10010 There is otherwise no method to distinguish between valid and
10011 invalidated certificates.
10012 \*(UA currently offers no mechanism to fetch CRLs, nor to access them on
10013 the Internet, so you have to retrieve them by some external mechanism.
10016 \*(UA accepts CRLs in PEM format only;
10017 CRLs in DER format must be converted, like, e.\|g.:
10020 .Dl $ openssl crl \-inform DER \-in crl.der \-out crl.pem
10023 To tell \*(UA about the CRLs, a directory that contains all CRL files
10024 (and no other files) must be created.
10029 variables, respectively, must then be set to point to that directory.
10030 After that, \*(UA requires a CRL to be present for each CA that is used
10031 to verify a certificate.
10034 .\" .Ss "Handling spam" {{{
10035 .Ss "Handling spam"
10037 \*(OP \*(UA can make use of several spam interfaces for the purpose of
10038 identification of, and, in general, dealing with spam messages.
10039 A precondition of most commands in order to function is that the
10041 variable is set to one of the supported interfaces.
10042 Once messages have been identified as spam their (volatile)
10044 state can be prompted: the
10048 message specifications will address respective messages and their
10050 entries will be used when displaying the
10052 in the header display.
10057 rates the given messages and sets their
10060 If the spam interface offers spam scores those can also be displayed in
10061 the header display by including the
10071 will interact with the Bayesian filter of the chosen interface and learn
10072 the given messages as
10076 respectively; the last command can be used to cause
10078 of messages; it adheres to their current
10080 state and thus reverts previous teachings.
10085 will simply set and clear, respectively, the mentioned volatile
10087 message flag, without any interface interaction.
10096 requires a running instance of the
10098 server in order to function, started with the option
10100 shall Bayesian filter learning be possible.
10102 .Bd -literal -offset indent
10103 $ spamd -i localhost:2142 -i /tmp/.spamsock -d [-L] [-l]
10104 $ spamd --listen=localhost:2142 --listen=/tmp/.spamsock \e
10105 --daemonize [--local] [--allow-tell]
10109 Thereafter \*(UA can make use of these interfaces:
10111 .Bd -literal -offset indent
10112 $ \*(uA -Sspam-interface=spamc -Sspam-maxsize=500000 \e
10113 -Sspamc-command=/usr/local/bin/spamc \e
10114 -Sspamc-arguments="-U /tmp/.spamsock" -Sspamc-user=
10116 $ \*(uA -Sspam-interface=spamc -Sspam-maxsize=500000 \e
10117 -Sspamc-command=/usr/local/bin/spamc \e
10118 -Sspamc-arguments="-d localhost -p 2142" -Sspamc-user=
10122 Using the generic filter approach allows usage of programs like
10124 Here is an example, requiring it to be accessible via
10127 .Bd -literal -offset indent
10128 $ \*(uA -Sspam-interface=filter -Sspam-maxsize=500000 \e
10129 -Sspamfilter-ham="bogofilter -n" \e
10130 -Sspamfilter-noham="bogofilter -N" \e
10131 -Sspamfilter-nospam="bogofilter -S" \e
10132 -Sspamfilter-rate="bogofilter -TTu 2>/dev/null" \e
10133 -Sspamfilter-spam="bogofilter -s" \e
10134 -Sspamfilter-rate-scanscore="1;^(.+)$"
10138 Because messages must exist on local storage in order to be scored (or
10139 used for Bayesian filter training), it is possibly a good idea to
10140 perform the local spam check last:
10142 .Bd -literal -offset indent
10143 define spamdelhook {
10145 spamset (header x-dcc-brand-metrics "bulk")
10146 # Server-side spamassassin(1)
10147 spamset (header x-spam-flag "YES")
10148 del :s # TODO we HAVE to be able to do `spamrate :u ! :sS'
10149 move :S +maybe-spam
10152 move :S +maybe-spam
10154 set folder-hook-FOLDER=spamdelhook
10158 See also the documentation for the variables
10159 .Va spam-interface , spam-maxsize ,
10160 .Va spamc-command , spamc-arguments , spamc-user ,
10161 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
10164 .Va spamfilter-rate-scanscore .
10172 In general it is a good idea to turn on
10178 twice) if something doesn't work well.
10179 Very often a diagnostic message can be produced that leads to the
10180 problems' solution.
10182 .\" .Ss "\*(UA shortly hangs on startup" {{{
10183 .Ss "\*(UA shortly hangs on startup"
10185 This can have two reasons, one is the necessity to wait for a file lock
10186 and can't be helped, the other being that \*(UA calls the function
10188 in order to query the nodename of the box (sometimes the real one is
10189 needed instead of the one represented by the internal variable
10191 You may have varying success by ensuring that the real hostname and
10195 or, more generally, that the name service is properly setup \(en
10198 return what you'd expect?
10199 Does this local hostname has a domain suffix?
10200 RFC 6762 standardized the link-local top-level domain
10204 .\" .Ss "I can't login to Google mail aka GMail" {{{
10205 .Ss "I can't login to Google mail aka GMail"
10207 Since 2014 some free service providers classify programs as
10209 unless they use a special authentification method (OAuth 2.0) which
10210 wasn't standardized for non-HTTP protocol authentication token query
10211 until August 2015 (RFC 7628).
10214 Different to Kerberos / GSSAPI, which is developed since the mid of the
10215 1980s, where a user can easily create a local authentication ticket for
10216 her- and himself with the locally installed
10218 program, that protocol has no such local part but instead requires
10219 a world-wide-web query to create or fetch a token; since there is no
10220 local cache this query has to be performed whenever \*(UA is invoked
10221 from the command line (in interactive sessions situation may differ).
10224 \*(UA doesn't support OAuth.
10225 Because of this it is necessary to declare \*(UA a
10226 .Dq less secure app
10227 (on the providers account web page) in order to read and send mail.
10228 However, it also seems possible to take the following steps instead:
10233 give the provider the number of a mobile phone,
10236 .Dq 2-Step Verification ,
10238 create an application specific password (16 characters), and
10240 use that special password instead of your real Google account password in
10241 \*(UA (for more on that see the section
10242 .Sx "On URL syntax and credential lookup" ) .
10246 .\" .Ss "Not \(dqdefunctional\(dq, but the editor key won't work" {{{
10247 .Ss "Not \(dqdefunctional\(dq, but the editor key won't work"
10249 It can happen that the terminal library (see
10250 .Sx "On terminal control and line editor",
10253 reports different codes than the terminal really sends, in which case
10254 \*(UA will tell that a key binding is functional, but won't be able to
10255 recognize it because the received data doesn't match anything expected.
10256 The verbose listing of
10258 ings will show the byte sequences that are expected.
10261 To overcome the situation, use, e.g., the program
10263 in conjunction with the
10265 flag if available, to see the byte sequences which are actually produced
10266 by keypresses, and use the variable
10268 to make \*(UA aware of them.
10269 E.g., the terminal this is typed on produces some false sequences, here
10270 an example showing the shifted home key:
10272 .Bd -literal -offset indent
10275 # 1B 5B=[ 31=1 3B=; 32=2 48=H
10280 ? \*(uA -v -Stermcap='kHOM=\eE[H'
10289 .\" .Sh "SEE ALSO" {{{
10299 .Xr spamassassin 1 ,
10308 .Xr mailwrapper 8 ,
10313 .\" .Sh HISTORY {{{
10316 M. Douglas McIlroy writes in his article
10317 .Dq A Research UNIX Reader: Annotated Excerpts \
10318 from the Programmer's Manual, 1971-1986
10321 command already appeared in First Edition
10325 .Bd -ragged -offset indent
10326 Electronic mail was there from the start.
10327 Never satisfied with its exact behavior, everybody touched it at one
10328 time or another: to assure the safety of simultaneous access, to improve
10329 privacy, to survive crashes, to exploit uucp, to screen out foreign
10330 freeloaders, or whatever.
10331 Not until v7 did the interface change (Thompson).
10332 Later, as mail became global in its reach, Dave Presotto took charge and
10333 brought order to communications with a grab-bag of external networks
10339 Mail was written in 1978 by Kurt Shoens and developed as part of the
10342 distribution until 1995.
10343 Mail has then seen further development in open source
10345 variants, noticeably by Christos Zoulas in
10347 Basing upon this Nail, later Heirloom Mailx, was developed by Gunnar
10348 Ritter in the years 2000 until 2008.
10349 Since 2012 S-nail is maintained by Steffen (Daode) Nurpmeso.
10350 This man page is derived from
10351 .Dq The Mail Reference Manual
10352 that was originally written by Kurt Shoens.
10358 .An "Kurt Shoens" ,
10359 .An "Edward Wang" ,
10360 .An "Keith Bostic" ,
10361 .An "Christos Zoulas" ,
10362 .An "Gunnar Ritter" ,
10363 .An "Steffen Nurpmeso" Aq Mt s-nail-users@lists.sourceforge.net
10365 .Mt s-mailx@sdaoden.eu ) .
10368 .\" .Sh CAVEATS {{{
10371 \*(ID Interrupting an operation via
10375 is often problematic: many library functions cannot deal with the
10377 that this software (still) performs.
10380 The SMTP and POP3 protocol support of \*(UA is very basic.
10381 Also, if it fails to contact its upstream SMTP server, it will not make
10382 further attempts to transfer the message at a later time (setting
10387 If this is a concern, it might be better to set up a local SMTP server
10388 that is capable of message queuing.
10394 After deleting some message of a POP3 mailbox the header summary falsely
10395 claims that there are no messages to display, you need to perform
10396 a scroll or dot movement to restore proper state.
10398 In threaded display a power user may encounter crashes very
10399 occasionally (this is may and very).
10403 in the source repository lists future directions.