1 .\"@ nail.1 - S-nail(1) reference manual.
3 .\" Copyright (c) 2000-2008 Gunnar Ritter, Freiburg i. Br., Germany.
4 .\" Copyright (c) 2012 - 2015 Steffen (Daode) Nurpmeso <steffen@sdaoden.eu>.
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34 .\" S-nail(1): v14.8.10 / 2016-08-20
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, but it is also possible to give
233 a comma-separated list of receivers in a single argument, proper quoting
235 .Ql -b """qrec1 , rec2,rec3, Ex <am@ple>""" .
237 .Sx "On sending mail, and non-interactive mode" .
241 Send carbon copies to the given receiver(s).
242 May be used multiple times.
248 variable which enables debug messages and disables message delivery,
249 among others; effectively turns almost any operation into a dry-run.
255 variable and thus discard messages with an empty message part body.
256 This is useful for sending messages from scripts.
260 Just check if mail is present (in the specified or system
262 box): if yes, return an exit status of zero, a non-zero value otherwise.
263 To restrict the set of mails to consider in this evaluation a message
264 specification can be added with the option
269 Save the message to send in a file named after the local part of the
270 first recipient's address (instead of in
275 Read in the contents of the user's
277 (or the specified file) for processing;
278 when \*(UA is quit, it writes undeleted messages back to this file
282 Some special conventions are recognized for the optional
284 argument which are documented for the
289 is not a argument to the flag
291 but is instead taken from the command line after option processing has
295 that starts with a hyphen, prefix it with a (relative) path, as in
296 .Ql ./-hyphenbox.mbox .
300 Display a summary of the
302 of all messages in the specified or system
305 A configurable summary view is available via the
311 Show a short usage summary.
312 Because of widespread use a
314 argument will have the same effect.
320 variable to ignore tty interrupt signals.
323 .It Fl L Ar spec-list
324 Display a summary of all
326 of only those messages in the specified or system
328 box that match the given
332 .Sx "Specifying messages"
339 option has been given in addition no header summary is produced,
340 but \*(UA will instead indicate via its exit status whether
346 note that any verbose output is suppressed in this mode and must instead
347 be enabled explicitly (e.g., by using the option
352 Special send mode that will flag standard input with the MIME
356 and use it as the main message body.
357 \*(ID Using this option will bypass processing of
358 .Va message-inject-head ,
361 .Va message-inject-tail .
367 Special send mode that will MIME classify the specified
369 and use it as the main message body.
370 \*(ID Using this option will bypass processing of
371 .Va message-inject-head ,
374 .Va message-inject-tail .
382 variable and thus inhibit initial display of message headers when
383 reading mail or editing a mail folder.
387 Standard flag that inhibits reading the system wide
392 allows more control over the startup sequence; also see
393 .Sx "Resource files" .
397 Special send mode that will initialize the message body with the
398 contents of the specified
400 which may be standard input
402 only in non-interactive context.
408 Any folder opened will be in read-only mode.
411 .It Fl r Ar from-addr
414 is a valid address then it specifies the envelope sender address to be
415 passed to a file-based
417 (Mail-Transfer-Agent) as
419 when a message is send.
422 include a user name, then the address components will be separated and
423 the name part will be passed to file-based
429 will also be assigned to the
432 .Ql -Sfrom=from-addr ) ,
433 therefore affecting possible SMTP
435 data transfer; note this assignment does not cause value fixation.
437 If instead an empty string is passed as
439 then the content of the variable
441 will be evaluated and used for this purpose whenever the
444 Note that \*(UA by default, without
446 that is, neither passes
450 flags to a file-based MTA by itself.
453 .It Fl S Ar var Ns Op = Ns value
456 iable and, in case of a value variable, assigns
459 Even though variables (see
460 .Sx "INTERNAL VARIABLES" )
464 may be overwritten from within resource files,
465 the command line setting will be reestablished after all resource files
470 Specify the subject of the to-be-sent message.
474 The message given (on standard input) is expected to contain, separated
475 from the message body by an empty line, a message header with
480 fields giving its recipients, which will be added to any recipients
481 specified on the command line.
482 If a message subject is specified via
484 then it'll be used in favour of one given on the command line.
502 .Ql Mail-Followup-To: ,
503 by default created automatically dependent on message context, will
504 be used if specified (a special address massage will however still occur
506 Any other (even custom) header field is passed through entirely
507 unchanged, and in conjunction with the option
509 it is even possible to embed
516 Initially read the primary system mailbox of
518 appropriate privileges presumed; effectively identical to
523 Show \*(UA's version and exit.
529 variable 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 -:/ -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 sets
575 is enabled in compose mode.
576 The following prepares an email message in a batched dry run:
577 .Bd -literal -offset indent
578 $ LC_ALL=C printf 'm bob\en~s ubject\enText\en~.\enx\en' | \e
579 LC_ALL=C \*(uA -:/ -d# -X'alias bob bob@exam.ple'
584 This flag forces termination of option processing in order to prevent
587 It also forcefully puts \*(UA into send mode, see
588 .Sx "On sending mail, and non-interactive mode" .
592 In the above list of supported command line options,
596 are implemented by means of setting the respective option, as via
599 .Op Ar mta-option ...
601 arguments that are given at the end of the command line after a
603 separator will be passed through to a file-based
605 (Mail-Transfer-Agent) and persist for an entire (interactive) session
606 \(en if the setting of
608 allows their recognition; no such constraints apply to the variable
612 .\" .Ss "A starter" {{{
615 \*(UA is a direct descendant of
617 Mail, a successor of the Research
620 .Dq was there from the start
625 Mail reference manual begins with the following words:
627 .Bd -ragged -offset indent
628 Mail provides a simple and friendly environment for sending and
630 It divides incoming mail into its constituent messages and allows the
631 user to deal with them in any order.
632 In addition, it provides a set of
634 -like commands for manipulating messages and sending mail.
635 Mail offers the user simple editing capabilities to ease the composition
636 of outgoing messages, as well as providing the ability to define and
637 send to names which address groups of users.
641 \*(UA is thus the user side of the
643 mail system, whereas the system side (Mail-Transfer-Agent, MTA) was
644 traditionally taken by
646 and most MTAs provide a binary of this name for compatibility purposes.
651 of \*(UA then the system side is not a mandatory precondition for mail
655 Because \*(UA strives for compliance with POSIX
657 it is likely that some configuration settings have to be adjusted before
658 using it is a smooth experience.
661 file already bends those standard imposed settings a bit towards more
662 user friendliness and safety, e.g., it sets the
666 variables in order to suppress the automatic moving of messages to
668 that would otherwise occur (see
669 .Sx "Message states" )
672 to not remove empty files in order not to mangle file permissions when
673 files eventually get recreated (\*(UA actively manages the file mode
676 upon program startup).
680 .Sx "INTERNAL VARIABLES" ,
681 isn't set by default so that file grouping (via the
683 prefix as documented for
685 is not functional by default.
688 contains some suggestions.
691 .\" .Ss "On sending mail, and non-interactive mode" {{{
692 .Ss "On sending mail, and non-interactive mode"
694 To send a message to one or more people, using a local or a builtin
696 (Mail-Transfer-Agent) transport to actually deliver the generated mail
697 message, \*(UA can be invoked with arguments which are the names of
698 people to whom the mail will be sent, and the command line options
702 can be used to add (blind) carbon copy receivers:
704 .Bd -literal -offset indent
705 $ \*(uA -s ubject -a ttach.txt bill@exam.ple
706 # But... try it in an isolated dry-run mode first
707 $ LC_ALL=C \*(uA -:/ -d -vv -Ssendwait \e
708 -b bcc@exam.ple -c cc@exam.ple -. \e
709 '(Lovely) Bob <bob@exam.ple>' eric@exam.ple
711 $ LC_ALL=C \*(uA -:/ -d -vv -Sv15-compat -Ssendwait \e
712 -S 'mta=smtps://mylogin@exam.ple:465' -Ssmtp-auth=login \e
713 -S 'from=scriptreply@exam.ple' \e
719 If standard input is a terminal rather than the message to be sent,
720 the user is expected to type in the message contents.
721 In this compose mode \*(UA treats lines beginning with the character
723 special \(en these are so-called
725 which can be used to read in files, process shell commands, add and edit
726 attachments and more; e.g., the tilde escape
728 will start the text editor to revise the message in it's current state,
730 allows editing of the most important message headers and
732 gives an overview of available tilde escapes.
736 at the beginning of an empty line leaves compose mode and causes the
737 message to be sent, whereas typing
740 twice will abort the current letter (saving its contents in the file
746 Messages are sent asynchronously, without supervision, unless the variable
748 is set, therefore send errors are not recognizable until then.
754 .Sx "INTERNAL VARIABLES"
755 can be used to alter default behavior; e.g.,
760 will automatically startup a text editor when compose mode is entered,
762 will cause the user to be prompted actively for carbon-copy recipients
765 option will allow leaving compose mode by writing a line consisting
771 hook macros may be set to automatically adjust some settings dependent
772 on receiver, sender or subject contexts.
775 Especially for using public mail provider accounts with the SMTP
777 it is often necessary to set
779 and saving a copy of sent messages in a
781 may be desirable \(en as for most mailbox file targets some special
782 syntax conventions are recognized (see the
784 command for more on that).
787 for the purpose of arranging a complete environment of settings that can
788 be switched to with a single command or command line option may be
791 contains example configurations for sending messages via some of the
792 well-known public mail providers and also gives a compact overview on
793 how to setup a secure SSL/TLS environment).
798 sandbox dry-run tests first will prove correctness.
802 .Sx "On URL syntax and credential lookup"
803 will spread light on the different ways of how to specify user email
804 account credentials, the
806 variable chains, and accessing protocol-specific resources,
809 goes into the details of character encoding and how to use them for
810 representing messages and MIME part contents by specifying them in
812 and reading the section
813 .Sx "The mime.types files"
814 should help to understand how the MIME-type of outgoing attachments are
815 classified, and what can be done for fine-tuning.
818 Message recipients (as specified on the command line or defined in
823 may not only be email addressees but can also be names of mailboxes and
824 even complete shell command pipe specifications.
827 is not set then only network addresses (see
829 for a description of mail addresses) and plain user names (including MTA
830 aliases) may be used, other types will be filtered out, giving a warning
833 .\" When changing any of the following adjust any RECIPIENTADDRSPEC;
834 .\" grep the latter for the complete picture
838 is set then extended recipient addresses will optionally be accepted:
839 Any name which starts with a vertical bar
841 character specifies a command pipe \(en the command string following the
843 is executed and the message is sent to its standard input;
844 Likewise, any name that starts with the character solidus
846 or the character sequence dot solidus
848 is treated as a file, regardless of the remaining content.
849 Any other name which contains an at sign
851 character is treated as a network address;
852 Any other name which starts with a plus sign
854 character specifies a mailbox name;
855 Any other name which contains a solidus
857 character but no exclamation mark
861 character before also specifies a mailbox name;
862 What remains is treated as a network address.
864 .Bd -literal -offset indent
865 $ echo bla | \*(uA -Sexpandaddr -s test ./mbox.mbox
866 $ echo bla | \*(uA -Sexpandaddr -s test '|cat >> ./mbox.mbox'
867 $ echo safe | LC_ALL=C \e
868 \*(uA -:/ -Sv15-compat -Ssendwait -Snosave \e
869 -Sexpandaddr=fail,-all,+addr -s test \e
874 It is possible to create personal distribution lists via the
876 command, so that, for instance, the user can send mail to
878 and have it go to a group of people.
879 These aliases have nothing in common with the system wide aliases that
880 may be used by the MTA, which are subject to the
884 and are often tracked in a file
890 Personal aliases will be expanded by \*(UA before the message is sent,
891 and are thus a convenient alternative to specifying each addressee by
895 .Dl alias cohorts bill jkf mark kridle@ucbcory ~/mail/cohorts.mbox
898 To avoid environmental noise scripts should
900 \*(UA from any configuration files and create a script-local
901 environment, ideally with the command line options
903 to disable any configuration file in conjunction with repetitions of
905 to specify variables:
907 .Bd -literal -offset indent
909 \*(uA -:/ -Sv15-compat -Ssendwait -Snosave \e
910 -Sexpandaddr=fail,-all,+addr \e
911 -S 'mta=smtps://mylogin@exam.ple:465' -Ssmtp-auth=login \e
912 -S 'from=scriptreply@exam.ple' \e
913 -s 'subject' -a attachment_file \e
914 -. "Recipient 1 <rec1@exam.ple>" rec2@exam.ple \e
919 In interactive mode, which is introduced in the next section, messages
920 can be sent by calling the
922 command with a list of recipient addresses \(em the semantics are
923 completely identical to non-interactive message sending:
925 .Bd -literal -offset indent
926 $ \*(uA -d -Squiet -Semptystart
927 "/var/spool/mail/user": 0 messages
928 ? mail "Recipient 1 <rec1@exam.ple>", rec2@exam.ple
929 ? # Will do the right thing (tm)
930 ? m rec1@exam.ple rec2@exam.ple
934 .\" .Ss "On reading mail, and interactive mode" {{{
935 .Ss "On reading mail, and interactive mode"
937 When invoked without addressees \*(UA enters interactive mode in which
939 When used like that the user's system
943 for an in-depth description of the different mailbox types that exist)
944 is read in and a one line header of each message therein is displayed.
945 The visual style of this summary of
947 can be adjusted through the variable
949 and the possible sorting criterion via
951 If the initially opened mailbox is empty \*(UA will instead exit
952 immediately (after displaying a message) unless the variable
961 will give a listing of all available commands and
963 will give a summary of some common ones.
964 If the \*(OPal documentation strings are available one can type
966 and see the actual expansion of
968 and what it's purpose is, i.e., commands can be abbreviated
969 (note that POSIX defines some abbreviations, so that the alphabetical
970 order of commands doesn't necessarily relate to the abbreviations; it is
971 possible to define overwrites with the
976 Messages are given numbers (starting at 1) which uniquely identify
977 messages; the current message \(en the
979 \(en will either be the first new message, or the first unread message,
980 or the first message of the mailbox; the option
982 will instead cause usage of the last message for this purpose.
987 ful of header summaries containing the
991 will display only the summaries of the given messages, defaulting to the
995 Message content can be displayed on the users' terminal with the
999 If instead the command
1001 is used, only the first
1003 of a message will be shown.
1004 By default the current message
1006 is displayed, but like with many other commands it is possible to give
1007 a fancy message specification (see
1008 .Sx "Specifying messages" ) ,
1011 will display all unread messages,
1016 will type the messages 1 and 5,
1018 will type the messages 1 through 5, and
1022 will display the last and the next message, respectively.
1025 (a more substantial alias of the standard command
1027 will display a header summary of the given message specification list
1028 instead of their content, e.g., the following will search for subjects:
1031 .Dl from "'@Some subject to search for'"
1034 In the default setup all header fields of a message will be
1036 d, but this can be changed: either by blacklisting a list of fields via
1038 or by whitelisting only a given list with the
1041 .Ql Ic \:retain Ns \0from_ date from to cc subject .
1042 In order to display all header fields of a message regardless of
1043 currently active ignore or retain lists, use the commands
1049 controls whether and when \*(UA will use the configured
1051 for display instead of directly writing to the user terminal
1053 (generally speaking).
1054 Note that historically the global
1056 not only adjusts the list of displayed headers, but also sets
1060 Dependent upon the configuration a line editor (see the section
1061 .Sx "On terminal control and line editor" )
1062 aims at making user experience with the many
1065 When reading the system
1071 specified a mailbox explicitly prefixed with the special
1073 modifier (propagating the mailbox to a primary one) then messages which
1074 have been read will be moved to a secondary mailbox, the user's
1076 file, automatically when the mailbox is left, either by changing the
1077 active mailbox or by quitting \*(UA (also see
1078 .Sx "Message states" )
1079 \(en this automatic moving from a system or primary to the secondary
1080 mailbox is not performed when the variable
1085 After examining a message the user can also
1089 to the sender and all recipients or
1091 exclusively to the sender(s).
1092 Messages can also be
1094 ed (shorter alias is
1096 Note that when replying to or forwarding a message recipient addresses
1097 will be stripped from comments and names unless the option
1100 Deletion causes \*(UA to forget about the message;
1101 This is not irreversible, though, one can
1103 the message by giving its number,
1104 or the \*(UA session can be ended by giving the
1109 To end a mail processing session one may either issue
1111 to cause a full program exit, which possibly includes
1112 automatic moving of read messages to
1114 as well as updating the \*(OPal line editor
1118 instead in order to prevent any of these actions.
1121 .\" .Ss "HTML mail and MIME attachments" {{{
1122 .Ss "HTML mail and MIME attachments"
1124 Messages which are HTML-only get more and more common and of course many
1125 messages come bundled with a bouquet of MIME attachments.
1126 Whereas \*(UA \*(OPally supports a simple HTML-to-text converter to deal
1127 with HTML messages (see
1128 .Sx "The mime.types files" ) ,
1129 it normally can't deal with any of these itself, but instead programs
1130 need to become registered to deal with specific MIME types or file
1132 These programs may either prepare plain text versions of their input
1133 in order to enable \*(UA to display the content on the terminal,
1134 or display the content themselves, for example in a graphical window.
1137 To install an external handler program for a specific MIME type set an
1139 .Va pipe-TYPE/SUBTYPE
1140 variable; to instead define a handler for a specific file extension set
1143 variable \(en these handlers take precedence.
1144 \*(OPally \*(UA supports mail user agent configuration as defined in
1145 RFC 1524; this mechanism, documented in the section
1146 .Sx "The Mailcap files" ,
1147 will be queried for display or quote handlers if none of the former two
1148 .\" TODO v15-compat "will be" -> "is"
1149 did; it will be the sole source for handlers of other purpose.
1150 A last source for handlers may be the MIME type definition itself, if
1151 the \*(UA specific type-marker extension was used when defining the type
1154 (Many of the builtin MIME types do so by default.)
1158 .Va mime-counter-evidence
1159 can be set to improve dealing with faulty MIME part declarations as are
1160 often seen in real-life messages.
1161 E.g., to display a HTML message inline (that is, converted to a more
1162 fancy plain text representation than the builtin converter is capable to
1163 produce) with either of the text-mode browsers
1167 teach \*(UA about MathML documents and make it display them as plain
1168 text, and to open PDF attachments in an external PDF viewer,
1169 asynchronously and with some other magic attached:
1171 .Bd -literal -offset indent
1172 if $features !@ +html-filter
1173 #set pipe-text/html='elinks -force-html -dump 1'
1174 set pipe-text/html='lynx -stdin -dump -force_html'
1175 # Display HTML as plain text instead
1176 #set pipe-text/html=@
1178 mimetype '@ application/mathml+xml mathml'
1179 wysh set pipe-application/pdf='@&=@ \e
1180 trap "rm -f \e"${NAIL_FILENAME_TEMPORARY}\e"" EXIT;\e
1181 trap "trap \e"\e" INT QUIT TERM; exit 1" INT QUIT TERM;\e
1182 mupdf "${NAIL_FILENAME_TEMPORARY}"'
1186 Note: special care must be taken when using such commands as mail
1187 viruses may be distributed by this method: if messages of type
1188 .Ql application/x-sh
1189 or files with the extension
1191 were blindly filtered through the shell, for example, a message sender
1192 could easily execute arbitrary code on the system \*(UA is running on.
1193 For more on MIME, also in respect to sending of messages, see the
1195 .Sx "The mime.types files" ,
1196 .Sx "The Mailcap files"
1201 .\" .Ss "Mailing lists" {{{
1204 \*(UA offers some support to ease handling of mailing lists.
1207 promotes all given arguments to known mailing lists, and
1209 sets their subscription attribute, creating them first as necessary.
1214 automatically, but only resets the subscription attribute.)
1215 Using the commands without arguments will show (a subset of) all
1216 currently defined mailing lists.
1221 can be used to mark out messages with configured list addresses
1222 in the header display.
1225 \*(OPally mailing lists may also be specified as (extended) regular
1226 expressions, which allows matching of many addresses with a single
1228 However, all fully qualified list addresses are matched via a fast
1229 dictionary, whereas expressions are placed in (a) list(s) which is
1230 (are) matched sequentially.
1232 .Bd -literal -offset indent
1233 set followup-to followup-to-honour=ask-yes reply-to-honour=ask-yes
1234 wysh mlist a1@b1.c1 a2@b2.c2 '.*@lists\e.c3$'
1235 mlsubscribe a4@b4.c4 exact@lists.c3
1240 .Va followup-to-honour
1242 .Ql Mail-\:Followup-\:To:
1243 header is honoured when the message is being replied to (via
1249 controls whether this header is created when sending mails; it will be
1250 created automatically for a couple of reasons, too, like when the
1252 .Dq mailing list specific
1257 is used to respond to a message with its
1258 .Ql Mail-Followup-To:
1262 A difference in between the handling of known and subscribed lists is
1263 that the address of the sender is usually not part of a generated
1264 .Ql Mail-Followup-To:
1265 when addressing the latter, whereas it is for the former kind of lists.
1266 Usually because there are exceptions: say, if multiple lists are
1267 addressed and not all of them are subscribed lists.
1269 For convenience \*(UA will, temporarily, automatically add a list
1270 address that is presented in the
1272 header of a message that is being responded to to the list of known
1274 Shall that header have existed \*(UA will instead, dependent on the
1276 .Va reply-to-honour ,
1279 for this purpose in order to accept a list administrators' wish that
1280 is supposed to have been manifested like that (but only if it provides
1281 a single address which resides on the same domain as what is stated in
1285 .\" .Ss "Resource files" {{{
1286 .Ss "Resource files"
1288 Upon startup \*(UA reads in several resource files:
1290 .Bl -tag -width ".It Pa _AIL_EXTRA_R_"
1293 System wide initialization file.
1294 Reading of this file can be suppressed, either by using the
1298 command line options, or by setting the
1301 .Ev NAIL_NO_SYSTEM_RC .
1305 File giving initial commands.
1306 A different file can be chosen by setting the
1310 Reading of this file can be suppressed with the
1312 command line option.
1314 .It Va NAIL_EXTRA_RC
1315 Can be used to define an optional startup file to be read after all
1316 other resource files.
1317 It can be used to specify settings that are not understood by other
1319 implementations, for example.
1320 This variable is only honoured when defined in a resource file, e.g.,
1322 .Sx "INTERNAL VARIABLES" .
1326 The content of these files is interpreted as follows:
1329 .Bl -bullet -compact
1331 A lines' leading whitespace is removed.
1333 Empty lines are ignored.
1335 Any other line is interpreted as a command.
1336 It may be spread over multiple input lines if the newline character is
1338 by placing a reverse solidus character
1340 as the last character of the line; whereas any leading whitespace of
1341 follow lines is ignored, trailing whitespace before a escaped newline
1342 remains in the input.
1344 If the line (content) starts with the number sign
1346 then it is a comment-command \(en a real command! \(en and also ignored.
1347 This command is the only form of comment that is understood.
1351 Unless \*(UA is about to enter interactive mode syntax errors that occur
1352 while loading these files are treated as errors and cause program exit.
1353 More files with syntactically equal content can be
1355 The following, saved in a file, would be an examplary content:
1357 .Bd -literal -offset indent
1358 # This line is a comment command. And y\e
1359 es, it is really continued here.
1366 .\" .Ss "Character sets" {{{
1367 .Ss "Character sets"
1369 \*(OP \*(UA detects the character set of the terminal by using
1370 mechanisms that are controlled by the
1375 should give an overview); the \*(UA internal variable
1377 will be set to the detected terminal character set accordingly
1378 and will thus show up in the output of the commands
1384 However, a user supplied
1386 value is not overwritten by this detection mechanism: this
1388 must be used if the detection doesn't work properly,
1389 and it may be used to adjust the name of the locale character set.
1390 E.g., on BSD systems one may use a locale with the character set
1391 ISO8859-1, which is not a valid name for this character set; to be on
1392 the safe side, one may set
1394 to the correct name, which is ISO-8859-1.
1397 Note that changing the value doesn't mean much beside that,
1398 since several aspects of the real character set are implied by the
1399 locale environment of the system,
1400 and that stays unaffected by the content of an overwritten
1403 (This is mostly an issue when interactively using \*(UA, though.
1404 It is actually possible to send mail in a completely
1406 locale environment, an option that \*(UA's test-suite uses excessively.)
1409 If no character set conversion capabilities have been compiled into
1412 doesn't include the term
1416 will be the only supported character set,
1417 it is simply assumed that it can be used to exchange 8-bit messages,
1418 and the rest of this section does not apply;
1419 it may however still be necessary to explicitly set it if automatic
1420 detection fails, since in that case it defaults to the mentioned
1421 .\" (Keep in SYNC: ./nail.1:"Character sets", ./nail.h:CHARSET_*!)
1425 When reading messages, their text is converted into
1427 as necessary in order to display them on the users terminal.
1428 Unprintable characters and invalid byte sequences are detected
1429 and replaced by proper substitution characters (unless the variable
1431 was set once \*(UA was started).
1433 .Va charset-unknown-8bit
1434 to deal with another hairy aspect of message interpretation.
1437 When sending messages all their parts and attachments are classified.
1438 Whereas no character set conversion is performed on those parts which
1439 appear to be binary data,
1440 the character set being used must be declared within the MIME header of
1441 an outgoing text part if it contains characters that do not conform to
1442 the set of characters that are allowed by the email standards.
1443 Permissible values for character sets can be declared using the
1447 which defines a catch-all last-resort fallback character set that is
1448 implicitly appended to the list of character-sets in
1452 When replying to a message and the variable
1453 .Va reply-in-same-charset
1454 is set then the character set of the message being replied to is tried
1456 And it is also possible to make \*(UA work even more closely related to
1457 the current locale setting automatically by using the variable
1458 .Va sendcharsets-else-ttycharset ,
1459 please see there for more information.
1462 All the specified character sets are tried in order unless the
1463 conversion of the part or attachment succeeds.
1464 If none of the tried (8-bit) character sets is capable to represent the
1465 content of the part or attachment,
1466 then the message will not be sent and its text will optionally be
1470 In general, if the message
1471 .Dq Cannot convert from a to b
1472 appears, either some characters are not appropriate for the currently
1473 selected (terminal) character set,
1474 or the needed conversion is not supported by the system.
1475 In the first case, it is necessary to set an appropriate
1477 locale and/or the variable
1481 The best results are usually achieved when \*(UA is run in a UTF-8
1482 locale on a UTF-8 capable terminal, in which case the full Unicode
1483 spectrum of characters is available.
1484 In this setup characters from various countries can be displayed,
1485 while it is still possible to use more simple character sets for sending
1486 to retain maximum compatibility with older mail clients.
1489 On the other hand the POSIX standard defines a locale-independent 7-bit
1490 .Dq portable character set
1491 that should be used when overall portability is an issue, the even more
1492 restricted subset named
1493 .Dq portable filename character set
1494 consisting of A-Z, a-z, 0-9, period
1503 .\" .Ss "Message states" {{{
1504 .Ss "Message states"
1506 \*(UA differentiates in between several different message states;
1507 the current state will be reflected in header summary displays if
1509 is configured to do so (via the internal variable
1511 and messages can also be selected and be acted upon depending on their
1513 .Sx "Specifying messages" ) .
1514 When operating on the system
1516 box or in primary mailboxes opened with the special prefix
1520 special actions, like the automatic moving of messages to the secondary
1522 mailbox may be applied when the mailbox is left (also implicitly via
1523 a successful exit of \*(UA, but not if the special command
1525 is used) \(en however, because this may be irritating to users which
1528 mail-user-agents, the default global
1534 variables in order to suppress this behaviour.
1536 .Bl -tag -width ".It Ql _reserved"
1538 Message has neither been viewed nor moved to any other state.
1539 Such messages are retained even in the primary system mailbox.
1542 Message has neither been viewed nor moved to any other state, but the
1543 message was present already when the mailbox has been opened last:
1544 Such messages are retained even in the primary system mailbox.
1547 The message has been processed by one of the following commands:
1567 commands may also cause the next message to be marked as read, depending
1573 command is used, messages that are in the primary system mailbox or in
1574 mailboxes which were opened with the special
1578 state when the mailbox is left will be saved in
1585 The message has been processed by one of the following commands:
1591 can be used to access such messages.
1594 The message has been processed by a
1596 command and it will be retained in its current location.
1599 The message has been processed by one of the following commands:
1605 command is used, messages that are in the primary system mailbox or in
1606 mailboxes which were opened with the special
1610 state when the mailbox is left will be deleted; they will be saved in
1618 .\" .Ss "Specifying messages" {{{
1619 .Ss "Specifying messages"
1626 can be given a list of message numbers as arguments to apply to a number
1627 of messages at once.
1630 deletes messages 1 and 2,
1633 will delete the messages 1 through 5.
1634 In sorted or threaded mode (see the
1638 will delete the messages that are located between (and including)
1639 messages 1 through 5 in the sorted/threaded order, as shown in the
1642 Multiple colon modifiers can be joined into one, e.g.,
1644 The following special message names exist:
1646 .Bl -tag -width ".It Ar _n_u"
1652 All old messages (any not in state
1677 All answered messages
1682 All messages marked as draft.
1684 \*(OP All messages classified as spam.
1686 \*(OP All messages with unsure spam classification.
1688 The current message, the so-called
1691 The message that was previously the current message.
1693 The parent message of the current message,
1694 that is the message with the Message-ID given in the
1696 field or the last entry of the
1698 field of the current message.
1700 The next previous undeleted message,
1701 or the next previous deleted message for the
1704 In sorted/threaded mode,
1705 the next previous such message in the sorted/threaded order.
1707 The next undeleted message,
1708 or the next deleted message for the
1711 In sorted/threaded mode,
1712 the next such message in the sorted/threaded order.
1714 The first undeleted message,
1715 or the first deleted message for the
1718 In sorted/threaded mode,
1719 the first such message in the sorted/threaded order.
1722 In sorted/threaded mode,
1723 the last message in the sorted/threaded order.
1727 selects the message addressed with
1731 is any other message specification,
1732 and all messages from the thread that begins at it.
1733 Otherwise it is identical to
1738 the thread beginning with the current message is selected.
1743 All messages that were included in the message list for the previous
1746 .It Ar / Ns Ar string
1747 All messages that contain
1749 in the subject field (case ignored).
1756 the string from the previous specification of that type is used again.
1758 .It Xo Op Ar @ Ns Ar name-list Ns
1761 All messages that contain the given case-insensitive search
1763 ession; if the \*(OPal regular expression (see
1765 support is available
1767 will be interpreted as (an extended) one if any of the
1769 (extended) regular expression characters is seen.
1771 .Ar @ Ns Ar name-list
1772 part is missing, the search is restricted to the subject field body,
1775 specifies a comma-separated list of header fields to search, as in
1777 .Dl '@to,from,cc@Someone i ought to know'
1779 In order to search for a string that includes a
1781 (commercial at) character the
1783 is effectively non-optional, but may be given as the empty string.
1784 Some special header fields may be abbreviated:
1798 respectively and case-insensitively.
1803 can be used to search in (all of) the header(s) of the message, and the
1812 can be used to perform full text searches \(en whereas the former
1813 searches only the body, the latter also searches the message header.
1815 This message specification performs full text comparison, but even with
1816 regular expression support it is almost impossible to write a search
1817 expression that savely matches only a specific address domain.
1818 To request that the content of the header is treated as a list of
1819 addresses, and to strip those down to the plain email address which the
1820 search expression is to be matched against, prefix the header name
1821 (abbreviation) with a tilde
1824 .Dl @~f@@a\e.safe\e.domain\e.match$
1828 .Dq any substring matches
1831 header, which will match addresses (too) even if
1833 is set (and POSIX says
1834 .Dq any address as shown in a header summary shall be matchable in this form ) ;
1837 variable is set, only the local part of the address is evaluated
1838 for the comparison, not ignoring case, and the setting of
1840 is completely ignored.
1841 For finer control and match boundaries use the
1843 search expression; the \*(OPal IMAP-style
1845 expression can also be used if substring matches are desired.
1849 \*(OP IMAP-style SEARCH expressions may also be used.
1850 This addressing mode is available with all types of folders;
1851 \*(UA will perform the search locally as necessary.
1852 Strings must be enclosed by double quotes
1854 in their entirety if they contain white space or parentheses;
1855 within the quotes, only reverse solidus
1857 is recognized as an escape character.
1858 All string searches are case-insensitive.
1859 When the description indicates that the
1861 representation of an address field is used,
1862 this means that the search string is checked against both a list
1865 .Bd -literal -offset indent
1866 (\*qname\*q \*qsource\*q \*qlocal-part\*q \*qdomain-part\*q)
1871 and the addresses without real names from the respective header field.
1872 These search expressions can be nested using parentheses, see below for
1876 .Bl -tag -compact -width ".It Ar _n_u"
1877 .It Ar ( criterion )
1878 All messages that satisfy the given
1880 .It Ar ( criterion1 criterion2 ... criterionN )
1881 All messages that satisfy all of the given criteria.
1883 .It Ar ( or criterion1 criterion2 )
1884 All messages that satisfy either
1889 To connect more than two criteria using
1891 specifications have to be nested using additional parentheses,
1893 .Ql (or a (or b c)) ,
1897 .Ql ((a or b) and c) .
1900 operation of independent criteria on the lowest nesting level,
1901 it is possible to achieve similar effects by using three separate
1905 .It Ar ( not criterion )
1906 All messages that do not satisfy
1908 .It Ar ( bcc \*q Ns Ar string Ns Ar \*q )
1909 All messages that contain
1911 in the envelope representation of the
1914 .It Ar ( cc \*q Ns Ar string Ns Ar \*q )
1915 All messages that contain
1917 in the envelope representation of the
1920 .It Ar ( from \*q Ns Ar string Ns Ar \*q )
1921 All messages that contain
1923 in the envelope representation of the
1926 .It Ar ( subject \*q Ns Ar string Ns Ar \*q )
1927 All messages that contain
1932 .It Ar ( to \*q Ns Ar string Ns Ar \*q )
1933 All messages that contain
1935 in the envelope representation of the
1938 .It Ar ( header name \*q Ns Ar string Ns Ar \*q )
1939 All messages that contain
1944 .It Ar ( body \*q Ns Ar string Ns Ar \*q )
1945 All messages that contain
1948 .It Ar ( text \*q Ns Ar string Ns Ar \*q )
1949 All messages that contain
1951 in their header or body.
1952 .It Ar ( larger size )
1953 All messages that are larger than
1956 .It Ar ( smaller size )
1957 All messages that are smaller than
1961 .It Ar ( before date )
1962 All messages that were received before
1964 which must be in the form
1968 denotes the day of the month as one or two digits,
1970 is the name of the month \(en one of
1971 .Ql Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ,
1974 is the year as four digits, e.g.,
1978 All messages that were received on the specified date.
1979 .It Ar ( since date )
1980 All messages that were received since the specified date.
1981 .It Ar ( sentbefore date )
1982 All messages that were sent on the specified date.
1983 .It Ar ( senton date )
1984 All messages that were sent on the specified date.
1985 .It Ar ( sentsince date )
1986 All messages that were sent since the specified date.
1988 The same criterion as for the previous search.
1989 This specification cannot be used as part of another criterion.
1990 If the previous command line contained more than one independent
1991 criterion then the last of those criteria is used.
1995 .\" .Ss "On URL syntax and credential lookup" {{{
1996 .Ss "On URL syntax and credential lookup"
1998 \*(IN For accessing protocol-specific resources usage of Uniform
1999 Resource Locators (URL, RFC 1738) has become omnipresent.
2000 \*(UA expects and understands URLs in the following form;
2003 denote optional parts, optional either because there also exist other
2004 ways to define the information in question or because support of the
2005 part is protocol-specific (e.g.,
2007 is used by the IMAP protocol but not by POP3);
2012 are specified they must be given in URL percent encoded form (RFC 3986;
2020 .Dl PROTOCOL://[USER[:PASSWORD]@]server[:port][/path]
2023 Note that these \*(UA URLs most often don't conform to any real
2024 standard, but instead represent a normalized variant of RFC 1738 \(en
2025 they are not used in data exchange but only meant as a compact,
2026 easy-to-use way of defining and representing information in
2027 a well-known notation.
2030 Many internal variables of \*(UA exist in multiple versions, called
2031 variable chains for the rest of this document: the plain
2036 .Ql variable-USER@HOST .
2043 had been specified in the respective URL, otherwise it refers to the plain
2049 that had been found when doing the user chain lookup as is described
2052 will never be in URL percent encoded form, whether it came from an URL
2053 or not; i.e., values of
2054 .Sx "INTERNAL VARIABLES"
2055 must not be URL percent encoded.
2058 For example, whether an hypothetical URL
2059 .Ql smtp://hey%3Ayou@our.house
2060 had been given that includes a user, or whether the URL was
2061 .Ql smtp://our.house
2062 and the user had been found differently, to lookup the variable chain
2063 .Va smtp-use-starttls
2064 \*(UA first looks for whether
2065 .Ql smtp-\:use-\:starttls-\:hey:you@our.house
2066 is defined, then whether
2067 .Ql smtp-\:use-\:starttls-\:our.house
2068 exists before finally ending up looking at the plain variable itself.
2071 \*(UA obeys the following logic scheme when dealing with the
2072 necessary credential information of an account:
2078 has been given in the URL the variables
2082 are looked up; if no such variable(s) can be found then \*(UA will,
2083 when enforced by the \*(OPal variables
2084 .Va netrc-lookup-HOST
2091 specific entry which provides a
2093 name: this lookup will only succeed if unambiguous (one possible matching
2096 It is possible to load encrypted
2101 If there is still no
2103 then \*(UA will fall back to the user who is supposed to run \*(UA,
2104 the identity of which has been fixated during \*(UA startup and is
2105 known to be a valid user on the current host.
2108 Authentication: unless otherwise noted this will lookup the
2109 .Va PROTOCOL-auth-USER@HOST , PROTOCOL-auth-HOST , PROTOCOL-auth
2110 variable chain, falling back to a protocol-specific default should this
2116 has been given in the URL, then if the
2118 has been found through the \*(OPal
2120 that may have already provided the password, too.
2121 Otherwise the variable chain
2122 .Va password-USER@HOST , password-HOST , password
2123 is looked up and used if existent.
2125 Afterwards the complete \*(OPal variable chain
2126 .Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup
2130 cache is searched for a password only (multiple user accounts for
2131 a single machine may exist as well as a fallback entry without user
2132 but with a password).
2134 If at that point there is still no password available, but the
2135 (protocols') chosen authentication type requires a password, then in
2136 interactive mode the user will be prompted on the terminal.
2141 S/MIME verification works relative to the values found in the
2145 header field(s), which means that the values of
2146 .Va smime-sign , smime-sign-cert , smime-sign-include-certs
2148 .Va smime-sign-message-digest
2149 will not be looked up using the
2153 chains from above but instead use the corresponding values from the
2154 message that is being worked on.
2155 In unusual cases multiple and different
2159 combinations may therefore be involved \(en on the other hand those
2160 unusual cases become possible.
2161 The usual case is as short as:
2164 .Dl set mta=smtp://USER:PASS@HOST smtp-use-starttls \e
2165 .Dl \ \ \ \ smime-sign smime-sign-cert=+smime.pair
2170 contains complete example configurations.
2173 .\" .Ss "On terminal control and line editor" {{{
2174 .Ss "On terminal control and line editor"
2176 \*(OP \*(UA can be configured to support a line editor,
2177 history lists that can be saved in between sessions,
2178 and terminal control to improve interactive usage experience.
2179 For the former one may either link against an external library
2180 .Pf ( Xr readline 3 ;
2181 behaviour of \*(UA may differ slightly),
2182 or enable the builtin Mailx-Line-Editor (MLE).
2183 Prevent usage of a line editor in interactive mode by setting the
2185 .Va line-editor-disable .
2188 \*(OP Terminal control will be realized through one of the standard
2190 libraries, either the
2192 or, alternatively, the
2194 both of which will be initialized to work with the environment variable
2196 Terminal control will enhance or enable interactive usage aspects, e.g.,
2197 .Sx "Coloured display" ,
2198 and extend behaviour of the MLE, which may learn the byte-sequences of
2199 keys like the cursor and function keys, and which will automatically
2202 alternative screen shall the terminal support it.
2203 The internal variable
2205 can be used to overwrite settings or to learn (correct(ed)) keycodes.
2206 Actual interaction with the chosen library can be disabled completely by
2207 setting the internal variable
2208 .Va termcap-disable ;
2210 will be queried regardless, even if the \*(OPal support for the
2211 libraries has not been enabled at configuration time.
2216 feature is available then input from line editor prompts will be saved
2217 in a history list that can be searched in and be expanded from.
2218 Such saving can be prevented by prefixing input with any amount of
2220 Aspects of history, like allowed content, maximum size etc., can be
2221 configured with the variables
2224 .Va history-gabby-persist
2229 \*(OP The builtin \*(UA line editor MLE should work in all environments
2230 which comply to the ISO C standard
2232 and will support wide glyphs if possible (the necessary functionality
2233 had been removed from ISO C, but was included in
2235 Especially if the \*(OPal terminal control support is missing setting
2236 entries in the internal variable
2238 will help shall the MLE misbehave, see there for more.
2239 The MLE can support a little bit of
2243 The MLE supports a set of editing and control commands.
2244 By default (as) many (as possible) of these will be assigned to a set of
2245 single-letter control codes, which should work on any terminal.
2248 command is available then the MLE commands can also be accessed freely
2249 by assigning the command name, which is shown in parenthesis in the list
2250 below, to any desired key-sequence, and the MLE will instead and also use
2252 to establish its builtin key bindings
2253 (more of them if the \*(OPal terminal control is available),
2254 an action which can then be suppressed completely by setting
2255 .Va line-editor-no-defaults .
2256 The following uses the
2258 ell-style quote notation that is documented in the introductional
2261 combinations not mentioned either cause job control signals or don't
2262 generate a (unique) keycode:
2266 .Bl -tag -compact -width "Ql _M"
2268 Go to the start of the line
2269 .Pf ( Cd mle-go-home ) .
2272 Move the cursor backward one character
2273 .Pf ( Cd mle-go-bwd ) .
2276 Forward delete the character under the cursor;
2277 quits \*(UA if used on the empty line unless the
2280 .Pf ( Cd mle-del-fwd ) .
2283 Go to the end of the line
2284 .Pf ( Cd mle-go-end ) .
2287 Move the cursor forward one character
2288 .Pf ( Cd mle-go-fwd ) .
2291 Cancel current operation, full reset.
2292 If there is an active history search or tabulator expansion then this
2293 command will first reset that, reverting to the former line content;
2294 thus a second reset is needed for a full reset in this case
2295 .Pf ( Cd mle-reset ) .
2298 Backspace: backward delete one character
2299 .Pf ( Cd mle-del-bwd ) .
2303 Horizontal tabulator:
2304 try to expand the word before the cursor, also supporting \*(UA
2307 .Pf ( Cd mle-complete ) .
2309 .Cd mle-quote-rndtrip .
2313 commit the current line
2314 .Pf ( Cd mle-commit ) .
2317 Cut all characters from the cursor to the end of the line
2318 .Pf ( Cd mle-snarf-end ) .
2322 .Pf ( Cd mle-repaint ) .
2325 \*(OP Go to the next history entry
2326 .Pf ( Cd mle-hist-fwd ) .
2333 \*(OP Go to the previous history entry
2334 .Pf ( Cd mle-hist-bwd ) .
2337 Toggle roundtrip mode shell quotes, where produced,
2339 .Pf ( Cd mle-quote-rndtrip ) .
2340 This setting is temporary, and will be forgotten once the command line
2344 \*(OP Complete the current line from (the remaining) older history entries
2345 .Pf ( Cd mle-hist-srch-bwd ) .
2348 \*(OP Complete the current line from (the remaining) newer history entries
2349 .Pf ( Cd mle-hist-srch-fwd ) .
2352 Paste the snarf buffer
2353 .Pf ( Cd mle-paste ) .
2360 .Pf ( Cd mle-snarf-line ) .
2363 Prompts for a Unicode character (its hexadecimal number) to be inserted
2364 .Pf ( Cd mle-prompt-char ) .
2365 Note this command needs to be assigned to a single-letter control code
2366 in order to become recognized and executed during input of
2367 a key-sequence (only four single-letter control codes can be used for
2368 that shortcut purpose); this control code is special-treated and can't
2369 be part of any other sequence, because any occurrence will perform the
2371 function immediately.
2374 Cut the characters from the one preceding the cursor to the preceding
2376 .Pf ( Cd mle-snarf-word-bwd ) .
2379 Move the cursor forward one word boundary
2380 .Pf ( Cd mle-go-word-fwd ) .
2383 Move the cursor backward one word boundary
2384 .Pf ( Cd mle-go-word-bwd ) .
2387 Escape: reset a possibly used multibyte character input state machine
2388 and \*(OPally a lingering, incomplete key binding
2389 .Pf ( Cd mle-cancel ) .
2390 This command needs to be assigned to a single-letter control code in
2391 order to become recognized and executed during input of a key-sequence
2392 (only four single-letter control codes can be used for that shortcut
2394 This control code may also be part of a multi-byte sequence, but if
2395 a sequence is active and the very control code is currently also an
2396 expected input, then it will first be consumed by the active sequence.
2411 Cut the characters from the one after the cursor to the succeeding word
2413 .Pf ( Cd mle-snarf-word-fwd ) .
2423 this will immediately reset a possibly active search etc.
2427 ring the audible bell.
2431 .\" .Ss "Coloured display" {{{
2432 .Ss "Coloured display"
2434 \*(OP \*(UA can be configured to support a coloured display and font
2435 attributes by emitting ANSI / ISO 6429 SGR (select graphic rendition)
2437 Usage of colours and font attributes solely depends upon the
2438 capability of the detected terminal type that is defined by the
2439 environment variable
2441 and which can be fine-tuned by the user via the internal variable
2445 On top of what \*(UA knows about the terminal the boolean variable
2447 defines whether the actually applicable colour and font attribute
2448 sequences should also be generated when output is going to be paged
2449 through the external program defined by the environment variable
2454 This is not enabled by default because different pager programs need
2455 different command line switches or other configuration in order to
2456 support those sequences.
2457 \*(UA however knows about some widely used pagers and in a clean
2458 environment it is often enough to simply set
2460 please refer to that variable for more on this topic.
2465 is set then any active usage of colour and font attribute sequences
2466 is suppressed, but without affecting possibly established
2471 To define and control colours and font attributes a single multiplexer
2472 command family exists:
2474 shows or defines colour mappings for the given colour type (e.g.,
2477 can be used to remove mappings of a given colour type.
2478 Since colours are only available in interactive mode, it may make
2479 sense to conditionalize the colour setup by encapsulating it with
2482 .Bd -literal -offset indent
2483 if terminal && $features =@ +colour
2484 colour iso view-msginfo ft=bold,fg=green
2485 colour iso view-header ft=bold,fg=red "from,subject"
2486 colour iso view-header fg=red
2488 uncolour iso view-header from,subject
2489 colour iso view-header ft=bold,fg=magenta,bg=cyan
2490 colour 256 view-header ft=bold,fg=208,bg=230 subject,from
2491 colour mono view-header ft=bold
2492 colour mono view-header ft=bold,ft=reverse subject,from
2496 .\" }}} (DESCRIPTION)
2499 .\" .Sh COMMANDS {{{
2502 Each command is typed on a line by itself,
2503 and may take arguments following the command word.
2504 Command names may be abbreviated, in which case the first command that
2505 matches the given prefix will be used.
2508 can be used to show the list of all commands, either alphabetically
2509 sorted or in prefix search order (these don't match, also because the
2510 POSIX standard prescribes a set of abbreviations); a more verbose
2511 listing will be produced if either of
2516 \*(OPally the command
2520 when given an argument, will show a documentation string for the
2521 command matching the expanded argument, as in
2523 which should be a shorthand of
2527 For commands which take message lists as arguments, the next message
2528 forward that satisfies the command's requirements will be used shall no
2529 explicit message list have been specified.
2530 If there are no messages forward of the current message,
2531 the search proceeds backwards,
2532 and if there are no good messages at all,
2533 \*(UA shows an error message and aborts the command.
2534 \*(ID Non-message-list arguments can be quoted using the following methods:
2537 .Bl -bullet -compact -offset indent
2539 An argument can be enclosed between paired double-quotes
2544 any white space, shell word expansion, or reverse solidus characters
2545 (except as described next) within the quotes are treated literally as
2546 part of the argument.
2547 A double-quote will be treated literally within single-quotes and vice
2549 Inside such a quoted string the actually used quote character can be
2550 used nonetheless by escaping it with a reverse solidus
2556 An argument that is not enclosed in quotes, as above, can usually still
2557 contain space characters if those spaces are reverse solidus escaped, as in
2561 A reverse solidus outside of the enclosing quotes is discarded
2562 and the following character is treated literally as part of the argument.
2567 Some commands which don't take message-list arguments can also be
2568 prefixed with the special keyword
2570 to choose \*(INible behaviour, and some new commands support only the
2571 new quoting style (without that keyword) and are flagged \*(NQ.
2572 In the future \*(UA will (mostly) use
2574 compatible argument parsing:
2575 Non-message-list arguments can be quoted using the following shell-style
2576 mechanisms: the escape character, single-quotes, double-quotes and
2577 dollar-single-quotes; any unquoted number sign
2579 starts a comment that ends argument processing.
2580 The overall granularity of error reporting and diagnostics, also
2581 regarding function arguments and their content, will improve.
2585 .Bl -bullet -compact -offset indent
2587 The literal value of any character can be preserved by preceding it
2588 with the escape character reverse solidus
2592 will cause variable expansion of the given name: \*(UA
2593 .Sx "INTERNAL VARIABLES"
2596 (shell) variables can be accessed through this mechanism, brace
2597 enclosing the name is supported.
2600 Arguments which are enclosed in
2601 .Ql 'single-\:quotes'
2602 retain their literal value.
2603 A single-quote cannot occur within single-quotes.
2606 The literal value of all characters enclosed in
2607 .Ql \(dqdouble-\:quotes\(dq
2608 is retained, with the exception of dollar
2610 which will cause variable expansion, as above, backquote (grave accent)
2612 (which not yet means anything special), reverse solidus
2614 which will escape any of the characters dollar
2616 (to prevent variable expansion), backquote (grave accent)
2620 (to prevent ending the quote) and reverse solidus
2622 (to prevent escaping, i.e., to embed a reverse solidus character as-is),
2623 but has no special meaning otherwise.
2626 Arguments enclosed in
2627 .Ql $'dollar-\:single-\:quotes'
2628 extend normal single quotes in that reverse solidus escape sequences are
2629 expanded as follows:
2631 .Bl -tag -compact -width "Ql \eNNN"
2637 an escape character.
2639 an escape character.
2651 emits a reverse solidus character.
2655 double quote (escaping is optional).
2657 eight-bit byte with the octal value
2659 (one to three octal digits), optionally with an additional
2662 A 0 byte will suppress further output for the quoted argument.
2664 eight-bit byte with the hexadecimal value
2666 (one or two hexadecimal characters).
2667 A 0 byte will suppress further output for the quoted argument.
2669 the Unicode / ISO-10646 character with the hexadecimal codepoint value
2671 (one to eight hexadecimal digits) \(em note that Unicode defines the
2672 maximum code to be ever supported as
2677 This escape is only supported in locales which support Unicode (see
2678 .Sx "Character sets" ) ,
2679 in other cases the sequence will remain unexpanded unless the given code
2680 point is ASCII compatible.
2681 The character NUL will suppress further output for the quoted argument.
2685 except it takes only one to four hexadecimal digits.
2690 This is a mechanism that allows usage of the non-printable (ASCII and
2691 compatible) control codes 0 to 31: to be able to create a printable
2692 representation the numeric value 64 is added to the control code of
2693 desire, and the resulting ASCII character set code point is then
2694 printed, e.g., BEL is
2695 .Ql 7 + 64 = 71 = G .
2696 Often circumflex notation is used for the visualization purpose, e.g,
2698 but the reverse solid notation has been standardized:
2700 The control code NUL
2702 ends argument processing without producing further output.
2704 Non-standard extension: expand the given variable name, as above.
2705 Brace enclosing the name is supported.
2707 Not yet supported, just to raise awareness: Non-standard extension.
2713 .Sy Compatibility notes:
2714 \*(ID Note these are new mechanisms which are not supported by all
2716 Round-tripping (feeding in things shown in list modes again) are not yet
2717 stable or possible at all.
2718 On new-style command lines it is wise to quote semicolon
2722 characters in order to ensure upward compatibility: the author would
2723 like to see things like
2724 .Ql ? echo $'trouble\etahead' | cat >> in_the_shell.txt
2726 .Ql ? top 2 5 10; type 3 22
2728 Before \*(UA will switch entirely to shell-style argument parsing there
2729 will be a transition phase where using
2731 will emit obsoletion warnings.
2732 E.g., the following are equivalent:
2734 .Bd -literal -offset indent
2735 mlist @any\e\e.where\e\e.example\e\e.com
2736 wysh mlist '@any\e.where\e.example\e.com' # This is a comment
2737 wysh mlist $'@any\e\e\ex2Ewhere\e\e.example\e\e\e56com' # A comment
2738 wysh mlist "@any\e.where\e.example\e.com"
2742 In any event an unquoted reverse solidus at the end of a command line is
2743 discarded and the next line continues the command.
2744 \*(ID Note that line continuation is handled before the above parsing is
2745 applied, i.e., the parsers documented above will see merged lines.
2746 Filenames, where expected, are subsequently subjected to the following
2747 transformations, in sequence:
2750 .Bl -bullet -compact -offset indent
2752 If the filename begins with an unquoted plus sign, and the
2754 variable is defined,
2755 the plus sign will be replaced by the value of the
2757 variable followed by a solidus.
2760 variable is unset or is set to null, the filename will be unchanged.
2763 Meta expansions are applied to the filename: a leading tilde
2765 character will be replaced by the expansion of
2767 except when followed by a valid user name, in which case the home
2768 directory of the given user is used instead.
2773 will be replaced by the expansion of the variable, if possible; \*(UA
2774 .Sx "INTERNAL VARIABLES"
2777 (shell) variables can be accessed through this mechanism, and the usual
2778 escape mechanism has to be applied to prevent interpretation.
2779 If the fully expanded filename results in multiple pathnames and the
2780 command is expecting only one file, an error results.
2782 In interactive context, in order to allow simple value acceptance (via
2784 arguments will usually be displayed in a properly quoted form, e.g., a file
2785 .Ql diet\e is \ecurd.txt
2787 .Ql 'diet\e is \ecurd.txt' .
2791 The following commands are available:
2793 .Bl -tag -width ".Ic _ccount"
2800 ) command which follows.
2804 The comment-command causes the entire line to be ignored.
2806 this really is a normal command which' purpose is to discard its
2809 indicating special character, which means that, e.g., trailing comments
2810 on a line are not possible.
2814 Goes to the next message in sequence and types it
2820 Display the preceding message, or the n'th previous message if given
2821 a numeric argument n.
2825 Show the current message number (the
2830 Show a brief summary of commands.
2831 \*(OP Given an argument a synopsis for the command in question is
2832 shown instead; commands can be abbreviated in general and this command
2833 can be used to see the full expansion of an abbreviation including the
2834 synopsis, try, e.g.,
2839 and see how the output changes.
2849 Interprets the remainder of the word as a macro name and passes it
2854 is a shorter synonym for
2855 .Ql call Ar mymacro .
2859 (ac) Creates, selects or lists (an) account(s).
2860 Accounts are special incarnations of
2862 macros and group commands and variable settings which together usually
2863 arrange the environment for the purpose of creating an email account.
2864 Different to normal macros settings which are covered by
2866 \(en here by default enabled! \(en will not be reverted before the
2871 (case-insensitive) always exists, and all but it can be deleted via
2874 Without arguments a listing of all defined accounts is shown.
2875 With one argument the given account is activated: the system
2877 box of that account will be activated (as via
2879 and a possibly installed
2882 The two argument form is identical to defining a macro as via
2884 .Bd -literal -offset indent
2886 set folder=~/mail MAIL=+syste.mbox record=+sent.mbox
2887 set from='myname@myisp.example (My Name)'
2888 set mta=smtp://mylogin@smtp.myisp.example
2894 (a) With no arguments, shows all currently-defined aliases.
2895 With one argument, shows that alias.
2896 With more than one argument,
2897 creates a new alias or appends to an existing one.
2899 can be used to delete aliases.
2903 (alt) Manage a list of alternate addresses / names of the active user,
2904 members of which will be removed from recipient lists when replying to
2907 variable is not set).
2908 If arguments are given the set of alternate names is replaced by them,
2909 without arguments the current set is displayed.
2913 Takes a message list and marks each message as having been answered.
2914 This mark has no technical meaning in the mail system;
2915 it just causes messages to be marked in the header summary,
2916 and makes them specially addressable.
2921 \*(OP\*(NQ The bind command extends the MLE (see
2922 .Sx "On terminal control and line editor" )
2923 with freely configurable key bindings.
2924 With one argument all bindings for the given context are shown,
2925 specifying an asterisk
2927 will show the bindings of all contexts; a more verbose listing will be
2928 produced if either of
2933 With two or more arguments a binding is (re)established:
2934 the first argument is the context to which the binding shall apply,
2935 the second argument is a comma-separated list of the
2937 which form the binding, and any remaining arguments form the expansion.
2938 To indicate that a binding shall not be auto-committed, but that the
2939 expansion shall instead be furtherly editable by the user, an at-sign
2941 (that will be removed) can be placed last in the expansion, from which
2942 leading and trailing whitespace will finally be removed.
2945 Contexts define when a binding applies, i.e., a binding won't be seen
2946 unless the context for which it is defined for is currently active.
2947 This is not true for the binding
2949 which always applies, but which will be searched secondarily to a more
2950 specialized context and may thus have some or all of its key bindings
2951 transparently replaced by equal bindings of more specialized contexts.
2952 The available contexts are
2954 which always applies, and
2956 which applies to compose-mode.
2960 which form the binding are specified as a comma-separated list of
2961 byte-sequences, where each list entry corresponds to one key(press).
2962 \*(OPally a list entry may, indicated by a leading colon character
2964 also refer to the name of a terminal capability;
2965 several dozen names will be compiled into \*(UA and may be specified
2968 or, if existing, by their
2970 name, regardless of the actually used terminal control library.
2971 It is however possible to use any capability, as long as the name is
2972 resolvable by the control library or defined in the internal variable
2974 Input sequences are not case-normalized, so that an exact match is
2975 required to update or remove a binding.
2978 .Bd -literal -offset indent
2979 bind base $'\eE',d mle-snarf-word-fwd # Esc(ape)
2980 bind base $'\eE',$'\ec?' mle-snarf-word-bwd # Esc, Delete
2981 bind compose :kf1 ~e
2982 bind base $'\ecA',:khome,w 'echo An editable binding@'
2983 bind base a,b,c rm -rf / @ # Another editable binding
2987 Note that the entire comma-separated list is first parsed (over) as a
2988 shell-token with whitespace as the field separator, before being parsed
2989 and expanded for real with comma as the field separator, therefore
2990 whitespace needs to be properly quoted:
2991 shell-style quoting is documented in the introductional section of
2993 Using Unicode reverse solidus escape sequences renders a binding
2994 defunctional if the locale doesn't support Unicode (see
2995 .Sx "Character sets" ) ,
2996 and using terminal capabilities does so if no terminal control support
2997 is (currently) available.
3000 The following terminal capability names are builtin and can be used in
3002 or (if available) the two-letter
3004 notation regardless of the actually used library.
3005 See the respective manual for a list of capabilities.
3008 can be used to show all the capabilities of
3010 or the given terminal type;
3013 flag will also show supported (non-standard) extensions.
3016 .Bl -tag -compact -width kcuuf_or_kcuuf
3017 .It Cd kbs Ns \0or Cd kb
3019 .It Cd kdch1 Ns \0or Cd kD
3021 .It Cd kDC Ns \0or Cd *4
3022 \(em shifted variant.
3023 .It Cd kel Ns \0or Cd kE
3024 Clear to end of line.
3025 .It Cd kext Ns \0or Cd @9
3027 .It Cd kich1 Ns \0or Cd kI
3029 .It Cd kIC Ns \0or Cd #3
3030 \(em shifted variant.
3031 .It Cd khome Ns \0or Cd kh
3033 .It Cd kHOM Ns \0or Cd #2
3034 \(em shifted variant.
3035 .It Cd kend Ns \0or Cd @7
3037 .It Cd knp Ns \0or Cd kN
3039 .It Cd kpp Ns \0or Cd kP
3041 .It Cd kcub1 Ns \0or Cd kl
3042 Left cursor (with more modifiers: see below).
3043 .It Cd kLFT Ns \0or Cd #4
3044 \(em shifted variant.
3045 .It Cd kcuf1 Ns \0or Cd kr
3046 Right cursor (ditto).
3047 .It Cd kRIT Ns \0or Cd %i
3048 \(em shifted variant.
3049 .It Cd kcud1 Ns \0or Cd kd
3050 Down cursor (ditto).
3052 \(em shifted variant (only terminfo).
3053 .It Cd kcuu1 Ns \0or Cd ku
3056 \(em shifted variant (only terminfo).
3057 .It Cd kf0 Ns \0or Cd k0
3059 Add one for each function key up to
3064 .It Cd kf10 Ns \0or Cd k;
3066 .It Cd kf11 Ns \0or Cd F1
3068 Add one for each function key up to
3076 Some terminals support key-modifier combination extensions, e.g.,
3078 For example, the delete key,
3080 in its shifted variant, the name is mutated to
3082 then a number is appended for the states
3094 .Ql Shift+Alt+Control
3096 The same for the left cursor key,
3098 .Cd KLFT , KLFT3 , KLFT4 , KLFT5 , KLFT6 , KLFT7 , KLFT8 .
3101 Key bindings can be removed with the command
3103 It is advisable to use an initial escape or other control character (e.g.,
3105 for bindings which describe user key combinations (as opposed to purely
3106 terminal capability based ones), in order to avoid ambiguities whether
3107 input belongs to key sequences or not; it also reduces search time.
3110 may help shall keys and sequences be falsely recognized.
3115 Calls a macro that has been created via
3120 (ch) Change the working directory to
3122 or the given argument.
3128 \*(OP Only applicable to S/MIME signed messages.
3129 Takes a message list and a file name and saves the certificates
3130 contained within the message signatures to the named file in both
3131 human-readable and PEM format.
3132 The certificates can later be used to send encrypted messages to the
3133 respective message senders by setting
3134 .Va smime-encrypt-USER@HOST
3139 (ch) Change the working directory to
3141 or the given argument.
3147 Only applicable to threaded mode.
3148 Takes a message list and makes all replies to these messages invisible
3149 in header summaries, unless they are in state
3155 \*(OP\*(NQ Manage colour mappings for the type of colour given as the
3156 (case-insensitive) first argument, which must be one of
3158 for 256-colour terminals,
3163 for the standard 8-colour ANSI / ISO 6429 color palette and
3167 for monochrome terminals.
3168 Monochrome terminals cannot deal with colours, but only (some) font
3172 Without further arguments the list of all currently defined mappings
3173 for the given colour type is shown (as a special case giving
3177 will iterate over all types in order).
3178 Otherwise the second argument defines the mappable slot, the third
3179 argument a (comma-separated list of) colour and font attribute
3180 specification(s), and the optional fourth argument can be used to
3181 specify a precondition: if conditioned mappings exist they are tested in
3182 (creation) order unless a (case-insensitive) match has been found, and
3183 the default mapping (if any has been established) will only be chosen as
3185 The types of precondition available depend on the mappable slot, the
3186 following of which exist:
3189 Mappings prefixed with
3191 are used for the \*(OPal builtin Mailx-Line-Editor (MLE, see
3192 .Sx "On terminal control and line editor" )
3193 and don't support preconditions.
3195 .Bl -tag -compact -width view-partinfo
3197 This mapping is used for the position indicator that is visible when
3198 a line cannot be fully displayed on the screen.
3205 Mappings prefixed with
3207 are used in header summaries, and they all understand the preconditions
3209 (the current message) and
3211 for elder messages (only honoured in conjunction with
3212 .Va datefield-markout-older ) .
3214 .Bl -tag -compact -width view-partinfo
3216 This mapping is used for the
3218 that can be created with the
3222 formats of the variable
3225 For the complete header summary line except the
3227 and the thread structure.
3229 For the thread structure which can be created with the
3231 format of the variable
3236 Mappings prefixed with
3238 are used when displaying messages.
3240 .Bl -tag -compact -width view-partinfo
3242 This mapping is used for so-called
3244 lines, which are MBOX file format specific header lines.
3247 A comma-separated list of headers to which the mapping applies may be
3248 given as a precondition; if the \*(OPal regular expression support is
3249 available then if any of the
3251 (extended) regular expression characters is seen the precondition will
3252 be evaluated as (an extended) one.
3254 For the introductional message info line.
3255 .It Cd view-partinfo
3256 For MIME part info lines.
3260 The following (case-insensitive) colour definitions and font attributes
3261 are understood, multiple of which can be specified in a comma-separated
3271 It is possible (and often applicable) to specify multiple font
3272 attributes for a single mapping.
3275 foreground colour attribute:
3285 To specify a 256-color mode a decimal number colour specification in
3286 the range 0 to 255, inclusive, is supported, and interpreted as follows:
3288 .Bl -tag -compact -width "999 - 999"
3290 the standard ISO 6429 colors, as above.
3292 high intensity variants of the standard colors.
3294 216 colors in tuples of 6.
3296 grayscale from black to white in 24 steps.
3298 .Bd -literal -offset indent
3300 fg() { printf "\e033[38;5;${1}m($1)"; }
3301 bg() { printf "\e033[48;5;${1}m($1)"; }
3303 while [ $i -lt 256 ]; do fg $i; i=$(($i + 1)); done
3304 printf "\e033[0m\en"
3306 while [ $i -lt 256 ]; do bg $i; i=$(($i + 1)); done
3307 printf "\e033[0m\en"
3311 background colour attribute (see
3313 for possible values).
3317 Mappings may be removed with the command
3319 For a generic overview see the section
3320 .Sx "Coloured display" .
3325 (C) Copy messages to files whose names are derived from the author of
3326 the respective message and don't mark them as being saved;
3327 otherwise identical to
3332 (c) Copy messages to the named file and don't mark them as being saved;
3333 otherwise identical to
3338 \*(NQ With no arguments, shows all currently-defined custom headers.
3339 With one argument, shows that custom header.
3340 With more than one argument, creates a new or replaces an existing
3341 custom header with the name given as the first argument, the content of
3342 which being defined by the concatenated remaining arguments.
3344 can be used to delete custom headers.
3345 \*(ID Overwriting of automatically managed headers is neither supported
3347 Defined custom headers will be injected into newly composed or forwarded
3350 .Dl customhdr OpenPGP id=12345678; url=http://www.YYY.ZZ
3354 may also be used to inject custom headers; it is covered by
3359 Show the name of the current working directory.
3363 \*(OP For unencrypted messages this command is identical to
3365 Encrypted messages are first decrypted, if possible, and then copied.
3369 \*(OP For unencrypted messages this command is identical to
3371 Encrypted messages are first decrypted, if possible, and then copied.
3375 Without arguments the current list of macros, including their content,
3376 is shown, otherwise a macro is defined.
3377 A macro definition is a sequence of commands in the following form:
3378 .Bd -literal -offset indent
3387 A defined macro can be invoked explicitly by using the
3391 commands, or implicitly if a macro hook is triggered, e.g., a
3393 Note that interpretation of
3395 depends on how (i.e.,
3397 normal macro, folder hook, hook, account switch) the macro is invoked.
3398 Macros can be deleted via
3402 Macro behaviour, including option localization, will change in v15.
3403 Please be aware of that and possibly embed a version check in a resource
3408 (d) Marks the given message list as
3410 Deleted messages will neither be saved in
3412 nor will they be available for most other commands.
3424 Deletes the current message and displays the next message.
3425 If there is no next message, \*(UA says
3432 up or down by one message when given
3436 argument, respectively.
3440 Takes a message list and marks each given message as a draft.
3441 This mark has no technical meaning in the mail system;
3442 it just causes messages to be marked in the header summary,
3443 and makes them specially addressable.
3447 (ec) Echoes its arguments after applying
3449 expansions and filename transformations, as documented for
3454 (e) Point the text editor (as defined in
3456 at each message from the given list in turn.
3457 Modified contents are discarded unless the
3464 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3465 conditional \(em if the condition of a preceding
3467 was false, check the following condition and execute the following block
3468 if it evaluates true.
3473 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3474 conditional \(em if none of the conditions of the preceding
3478 commands was true, the
3484 (en) Marks the end of an
3485 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3486 conditional execution block.
3491 \*(NQ \*(UA has a strict notion about which variables are
3492 .Sx "INTERNAL VARIABLES"
3493 and which are managed in the program
3495 Since some of the latter are a vivid part of \*(UAs functioning,
3496 however, they are transparently integrated into the normal handling of
3497 internal variables via
3501 To integrate other environment variables of choice into this
3502 transparent handling, and also to export internal variables into the
3503 process environment where they normally are not, a
3505 needs to become established with this command, as in, e.g.,
3508 .Dl environ link PERL5LIB from TZ
3511 Afterwards changing such variables with
3513 will cause automatic updates of the program environment, and therefore
3514 be inherited by newly created child processes.
3515 Sufficient system support provided (it was in BSD as early as 1987, and
3516 is standardized since Y2K) removing such variables with
3518 will remove them also from the program environment, but in any way
3519 the knowledge they ever have been
3522 Note this implies that
3524 may cause loss of links.
3529 will remove an existing link, but leaves the variables as such intact.
3530 Additionally the subcommands
3534 are provided, which work exactly the same as the documented commands
3538 but (additionally) link the variable(s) with the program environment and
3539 thus immediately export them to, or remove them from (if possible),
3540 respectively, the program environment.
3545 \*(OP Since \*(UA uses the console as a user interface it can happen
3546 that messages scroll by too fast to become recognized.
3547 Optionally an error message ring queue is available which stores
3548 duplicates of any error message and notifies the user in interactive
3549 sessions whenever a new error has occurred.
3550 The queue is finite: if its maximum size is reached any new message
3551 replaces the eldest.
3554 can be used to manage this message queue: if given
3556 or no argument the queue will be displayed and cleared,
3558 will only clear all messages from the queue.
3562 (ex or x) Exit from \*(UA without changing the active mailbox and skip
3563 any saving of messages in
3565 as well as a possibly tracked line editor history file.
3569 Show the list of features that have been compiled into \*(UA.
3570 (Outputs the contents of the variable
3577 but open the mailbox readonly.
3581 (fi) The file command switches to a new mailbox.
3582 Without arguments it shows status information of the current mailbox.
3583 If an argument is given, it will write out changes (such as deletions)
3584 the user has made and open a new mailbox.
3585 Some special conventions are recognized for the
3589 .Bl -tag -compact -offset indent -width ".Ar %:__lespec"
3591 (number sign) means the previous file,
3593 (percent sign) means the invoking user's system
3597 means the primary system mailbox of
3599 (and never the value of
3601 regardless of its actual setting),
3603 (ampersand) means the invoking user's
3613 expands to the same value as
3615 but the file is handled as a primary system mailbox by, e.g., the
3619 commands, meaning that messages that have been read in the current
3620 session will be moved to the
3622 mailbox instead of simply being flagged as read.
3625 If the name matches one of the strings defined with the command
3627 it is replaced by its long form and expanded.
3628 If the name ends with
3633 it is treated as being compressed with
3638 respectively, and transparently handled through an intermediate
3639 (un)compression step (using a temporary file) with the according
3640 facility, sufficient support provided.
3641 Likewise, if the named file doesn't exist, but a file with one of the
3642 mentioned compression extensions does, then the name is automatically
3643 expanded and the compressed file is used.
3645 Otherwise, if the name ends with an extension for which
3646 .Va file-hook-load-EXTENSION
3648 .Va file-hook-save-EXTENSION
3649 variables are set, then the given hooks will be used to load and save
3651 and \*(UA will work with an intermediate temporary file.
3653 MBOX files (flat file-based mailboxes) are generally locked during file
3654 operations in order to avoid inconsistencies due to concurrent
3656 \*(OPal Mailbox files which \*(UA treats as system
3658 boxes or primary mailboxes will also be protected by so-called dotlock
3659 files, the traditional way of mail spool file locking: for any file
3663 will be created for the duration of the synchronization \(em
3664 as necessary a privilege-separated dotlock child process will be used
3665 to accommodate for necessary privilege adjustments in order to create
3666 the dotlock file in the same directory
3667 and with the same user and group identities as the file of interest.
3670 for fine-tuning the handling of MBOX files.
3674 refers to a directory with the subdirectories
3679 then it is treated as a folder in
3681 format; \*(ID the variable
3683 can be used to control the format of yet non-existent folders.
3686 .Dl \*(IN protocol://[user[:password]@]host[:port][/path]
3687 .Dl \*(OU protocol://[user@]host[:port][/path]
3689 is taken as an Internet mailbox specification.
3690 The \*(OPally supported protocols are
3694 (POP3 with SSL/TLS encrypted transport).
3697 part is valid only for IMAP; there it defaults to
3699 Also see the section
3700 .Sx "On URL syntax and credential lookup" .
3704 contains special characters, in particular
3708 they must be escaped in URL notation \(en the command
3710 can be used to show the necessary conversion.
3714 Takes a message list and marks the messages as
3716 ged for urgent/special attention.
3717 This mark has no technical meaning in the mail system;
3718 it just causes messages to be highlighted in the header summary,
3719 and makes them specially addressable.
3728 With no arguments, list the names of the folders in the folder directory.
3729 With an existing folder as an argument,
3730 lists the names of folders below the named folder.
3736 but saves the message in a file named after the local part of the first
3737 recipient's address (instead of in
3744 but saves the message in a file named after the local part of the first
3745 recipient's address (instead of in
3752 but responds to all recipients regardless of the
3757 .It Ic followupsender
3760 but responds to the sender only regardless of the
3776 (f) Takes a list of message specifications and displays a summary of
3777 their message headers, exactly as via
3779 An alias of this command is
3782 .Sx "Specifying messages" .
3788 but saves the message in a file named after the local part of the
3789 recipient's address (instead of in
3794 Takes a message and the address of a recipient
3795 and forwards the message to him.
3796 The text of the original message is included in the new one,
3797 with the value of the
3799 variable preceding it.
3804 commands specify which header fields are included in the new message.
3805 Only the first part of a multipart message is included unless the
3806 .Va forward-as-attachment
3810 is set recipient addresses will be stripped from comments, names etc.
3814 Specifies which header fields are to be ignored with the command
3816 This command has no effect when the
3817 .Va forward-as-attachment
3822 Specifies which header fields are to be retained with the command
3827 This command has no effect when the
3828 .Va forward-as-attachment
3833 Define or list command aliases, so-called ghosts.
3834 Without arguments a list of all currently known aliases is shown.
3835 With one argument the expansion of the given alias is shown.
3836 With two or more arguments a command alias is defined or updated: the
3837 first argument is the name under which the remaining command line should
3838 be accessible, the content of which can be just about anything.
3839 A ghost can be used everywhere a normal command can be used, but always
3840 takes precedence; any arguments that are given to the command alias are
3841 joined onto the alias content, and the resulting string forms the
3842 command line that is, in effect, executed.
3845 .Bd -literal -offset indent
3847 `ghost': no such alias: "xx"
3850 ghost xx "echo hello,"
3859 (h) Show the current group of headers, the size of which depends on
3862 and the style of which can be adjusted with the variable
3864 If a message-specification is given the group of headers containing the
3865 first message therein is shown and the message at the top of the screen
3880 the list of history entries;
3883 argument selects and shows the respective history entry \(en
3886 to accept it, and the history entry will become the new history top.
3887 The default mode if no arguments are given is
3894 Takes a message list and marks each message therein to be saved in the
3899 Does not override the
3902 \*(UA deviates from the POSIX standard with this command, because a
3904 command issued after
3906 will display the following message, not the current one.
3911 (i) Part of the nestable
3912 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3913 conditional execution construct \(em if the given condition is true then
3914 the encapsulated block is executed.
3915 POSIX only supports the (case-insensitive) conditions
3920 end, all remaining conditions are non-portable extensions; note that
3921 falsely specified conditions cause the execution of the entire
3922 conditional construct until the (matching) closing
3924 command to be suppressed.
3925 The syntax of the nestable
3927 conditional execution construct requires that each condition and syntax
3928 element is surrounded by whitespace.
3930 .Bd -literal -offset indent
3939 The (case-insensitive) condition
3941 erminal will evaluate to true if the standard input is a terminal, i.e.,
3942 in interactive sessions.
3943 Another condition can be any boolean value (see the section
3944 .Sx "INTERNAL VARIABLES"
3945 for textual boolean representations) to mark an enwrapped block as
3948 .Dq always execute .
3949 It is possible to check
3950 .Sx "INTERNAL VARIABLES"
3953 variables for existence or compare their expansion against a user given
3954 value or another variable by using the
3956 .Pf ( Dq variable next )
3957 conditional trigger character;
3958 a variable on the right hand side may be signalled using the same
3960 The variable names may be enclosed in a pair of matching braces.
3963 The available comparison operators are
3967 (less than or equal to),
3973 (greater than or equal to),
3977 (is substring of) and
3979 (is not substring of).
3980 The values of the left and right hand side are treated as strings and
3981 are compared 8-bit byte-wise, ignoring case according to the rules of
3982 the US-ASCII encoding (therefore, dependent on the active locale,
3983 possibly producing false results for strings in the locale encoding).
3984 Except for the substring checks the comparison will instead be performed
3985 arithmetically if both, the user given value as well as the variable
3986 content, can be parsed as numbers (integers).
3987 An unset variable is treated as the empty string.
3990 When the \*(OPal regular expression support is available, the additional
3996 They treat the right hand side as an extended regular expression that is
3997 matched case-insensitively and according to the active
3999 locale, meaning that strings in the locale encoding should be matched
4003 Conditions can be joined via AND-OR lists (where the AND operator is
4005 and the OR operator is
4007 which have equal precedence and will be evaluated with left
4008 associativity, thus using the same syntax that is known for the
4010 It is also possible to form groups of conditions and lists by enclosing
4011 them in pairs of brackets
4012 .Ql [\ \&.\&.\&.\ ] ,
4013 which may be interlocked within each other, and also be joined via
4017 The results of individual conditions and entire groups may be modified
4018 via unary operators: the unary operator
4020 will reverse the result.
4022 .Bd -literal -offset indent
4026 if $ttycharset == "UTF-8"
4027 echo *ttycharset* is set to UTF-8, case-insensitively
4031 echo These two variables are equal
4033 if $version-major >= 15
4034 echo Running a new version..
4035 if $features =@ +regex
4036 if $TERM =~ "^xterm\&.*"
4037 echo ..in an X terminal
4040 if [ [ true ] && [ [ ${debug} ] || [ $verbose ] ] ]
4043 if true && $debug || ${verbose}
4044 echo Left associativity, as is known from the shell
4046 if ! ! true && ! [ ! $debug && ! $verbose ]
4047 echo Unary operator support
4055 Without arguments the list of ignored header fields is shown,
4056 otherwise the given list of header fields is added to the ignore list:
4057 Header fields in the ignore list are not shown on the terminal when
4058 a message is displayed.
4059 To display a message in its entirety, use the commands
4070 Shows the names of all available commands, alphabetically sorted.
4071 If given any non-whitespace argument the list will be shown in the order
4072 in which command prefixes are searched.
4075 output is available.
4079 This command can be used to localize changes to variables, meaning that
4080 their state will be reverted to the former one once the covered scope
4082 It can only be used inside of macro definition blocks introduced by
4086 and is interpreted as a boolean (string, see
4087 .Sx "INTERNAL VARIABLES" ) ;
4090 of an account is left once it is switched off again.
4091 .Bd -literal -offset indent
4092 define temporary_settings {
4107 enables change localization and calls
4109 which explicitly resets localization, then any value changes within
4111 will still be reverted by
4113 \*(ID Once the outermost level, the one which enabled localization
4114 first, is left, but no earlier, all adjustments will be unrolled.
4118 Reply to messages that come in via known
4121 .Pf ( Ic mlsubscribe )
4122 mailing lists, or pretend to do so (see
4123 .Sx "Mailing lists" ) :
4126 functionality this will actively resort and even remove message
4127 recipients in order to generate a message that is supposed to be sent to
4129 For example it will also implicitly generate a
4130 .Ql Mail-Followup-To:
4131 header if that seems useful, regardless of the setting of the variable
4138 but saves the message in a file named after the local part of the first
4139 recipient's address (instead of in
4144 (m) Takes a (list of) recipient address(es) as (an) argument(s),
4145 or asks on standard input if none were given;
4146 then collects the remaining mail content and sends it out.
4150 (mb) The given message list is to be sent to
4152 when \*(UA is quit; this is the default action unless the
4155 \*(ID This command can only be used in a primary system mailbox (see
4160 Without any arguments the content of the MIME type cache will displayed.
4161 Otherwise each argument defines a complete MIME type specification of
4162 a type that shall be added (prepended) to the cache.
4163 In any event MIME type sources are loaded first as necessary \(en
4164 .Va mimetypes-load-control
4165 can be used to fine-tune which sources are actually loaded.
4166 Refer to the section on
4167 .Sx "The mime.types files"
4168 for more on MIME type specifications and this topic in general.
4169 MIME type unregistration and cache resets can be triggered with
4174 Without arguments the list of all currently defined mailing lists
4175 (and their attributes, if any) is shown; a more verbose listing will be
4176 produced if either of
4181 Otherwise all given arguments (which need not be quoted except for
4182 whitespace) will be added and henceforth be recognized as mailing lists.
4183 Mailing lists may be removed via the command
4186 If the \*(OPal regular expression support is available then mailing
4187 lists may also be specified as (extended) regular expressions (see
4193 Without arguments the list of all currently defined mailing lists which
4194 have a subscription attribute is shown; a more verbose listing will be
4195 produced if either of
4200 Otherwise this attribute will be set for all given mailing lists,
4201 newly creating them as necessary (as via
4203 Subscription attributes may be removed via the command
4212 but moves the messages to a file named after the local part of the
4213 sender address of the first message (instead of in
4220 but marks the messages for deletion if they were transferred
4227 but also displays ignored header fields and all MIME parts.
4235 on the given messages, even in non-interactive mode and as long as the
4236 standard output is a terminal.
4242 \*(OP When used without arguments or if
4244 has been given the content of the
4246 cache is shown, loading it first as necessary.
4249 then the cache will only be initialized and
4251 will remove its contents.
4252 Note that \*(UA will try to load the file only once, use
4253 .Ql Ic \&\&netrc Ns \:\0\:clear
4254 to unlock further attempts.
4259 .Sx "On URL syntax and credential lookup" ;
4261 .Sx "The .netrc file"
4262 documents the file format in detail.
4266 Checks for new mail in the current folder without committing any changes
4268 If new mail is present, a message is shown.
4272 the headers of each new message are also shown.
4273 This command is not available for all mailbox types.
4281 Goes to the next message in sequence and types it.
4282 With an argument list, types the next matching message.
4296 If the current folder is accessed via a network connection, a
4298 command is sent, otherwise no operation is performed.
4304 but also displays ignored header fields and all MIME parts.
4312 on the given messages, even in non-interactive mode and as long as the
4313 standard output is a terminal.
4321 but also pipes ignored header fields and all parts of MIME
4322 .Ql multipart/alternative
4327 (pi) Takes a message list and a shell command
4328 and pipes the messages through the command.
4329 Without an argument the current message is piped through the command
4336 every message is followed by a formfeed character.
4357 (q) Terminates the session, saving all undeleted, unsaved messages in
4360 preserving all messages marked with
4364 or never referenced in the system
4366 box, and removing all other messages from the primary system mailbox.
4367 If new mail has arrived during the session,
4369 .Dq You have new mail
4371 If given while editing a mailbox file with the command line flag
4373 then the edit file is rewritten.
4374 A return to the shell is effected,
4375 unless the rewrite of edit file fails,
4376 in which case the user can escape with the exit command.
4390 Removes the named files or directories.
4391 If a name refer to a mailbox, e.g., a Maildir mailbox, then a mailbox
4392 type specific removal will be performed, deleting the complete mailbox.
4393 The user is asked for confirmation in interactive mode.
4397 Takes the name of an existing folder
4398 and the name for the new folder
4399 and renames the first to the second one.
4400 Both folders must be of the same type.
4404 (R) Reply to originator.
4405 Does not reply to other recipients of the original message.
4407 will exchange this command with
4411 is set the recipient address will be stripped from comments, names etc.
4415 (r) Take a message and group-responds to it by addressing the sender
4418 .Va followup-to-honour ,
4421 .Va recipients-in-cc
4422 influence response behaviour.
4425 offers special support for replying to mailing lists.
4428 is set recipient addresses will be stripped from comments, names etc.
4441 but initiates a group-reply regardless of the value of
4448 but responds to the sender only regardless of the value of
4455 but does not add any header lines.
4456 This is not a way to hide the sender's identity,
4457 but useful for sending a message again to the same recipients.
4461 Takes a list of messages and a user name
4462 and sends each message to the named user.
4464 and related header fields are prepended to the new copy of the message.
4482 .It Ic respondsender
4488 (ret) Without arguments the list of retained header fields is shown,
4489 otherwise the given list of header fields is added to the retain list:
4490 Header fields in the retain list are shown on the terminal when
4491 a message is displayed, all other header fields are suppressed.
4492 To display a message in its entirety, use the commands
4501 takes precedence over the mentioned.
4507 but saves the messages in a file named after the local part of the
4508 sender of the first message instead of (in
4510 and) taking a filename argument.
4514 (s) Takes a message list and a filename and appends each message in turn
4515 to the end of the file.
4516 If no filename is given, the
4519 The filename in quotes, followed by the generated character count
4520 is echoed on the user's terminal.
4521 If editing a primary system mailbox the messages are marked for deletion.
4522 Filename interpretation as described for the
4524 command is performed.
4541 Header fields thus marked are filtered out when saving a message by
4543 or when automatically saving to
4545 This command should only be applied to header fields that do not contain
4546 information needed to decode the message,
4547 as MIME content fields do.
4559 Header fields thus marked are the only ones saved with a message when
4562 or when automatically saving to
4567 The use of this command is strongly discouraged since it may strip
4568 header fields that are needed to decode the message correctly.
4572 Takes a message specification (list) and displays a header summary of
4573 all matching messages, as via
4575 This command is an alias of
4578 .Sx "Specifying messages" .
4582 Takes a message list and marks all messages as having been read.
4586 (se) Without arguments this command shows all internal variables which
4587 are currently known to \*(UA (they have been set).
4588 A more verbose listing will be produced if either of
4592 are set, in which case variables may be preceded with a comment line
4593 that gives some context of what \*(UA knows about the given variable.
4595 Otherwise the given variables (and arguments) are set or adjusted.
4596 Arguments are of the form
4598 (no space before or after
4602 if there is no value, i.e., a boolean variable.
4603 Quotation marks may be placed around any part of the assignment
4604 statement to quote blanks or tabs, e.g.,
4606 .Dl set indentprefix='->'
4608 If an argument begins with
4612 the effect is the same as invoking the
4614 command with the remaining part of the variable
4615 .Pf ( Ql unset save ) .
4619 that is known to map to an environment variable will automatically cause
4620 updates in the program environment (unsetting a variable in the
4621 environment requires corresponding system support).
4622 Please use the command
4624 for further environmental control.
4629 .Sx "INTERNAL VARIABLES"
4635 (sh) Invokes an interactive version of the shell.
4639 Without arguments the list of all currently defined shortcuts is
4641 Otherwise all given arguments (which need not be quoted except for
4642 whitespace) are treated as pairs of shortcuts and their expansions,
4643 creating new or changing already existing shortcuts, as necessary.
4644 Shortcuts may be removed via the command
4646 The expansion strings should be in the syntax that has been described
4655 but performs neither MIME decoding nor decryption, so that the raw
4656 message text is shown.
4660 (si) Shows the size in characters of each message of the given
4665 Shows the current sorting criterion when used without an argument.
4666 Otherwise creates a sorted representation of the current folder,
4669 command and the addressing modes such that they refer to messages in
4671 Message numbers are the same as in regular mode.
4675 a header summary in the new order is also displayed.
4676 Automatic folder sorting can be enabled by setting the
4678 variable, as in, e.g.,
4679 .Ql set autosort=thread .
4680 Possible sorting criterions are:
4682 .Bl -tag -compact -offset indent -width "subject"
4684 Sort the messages by their
4686 field, that is by the time they were sent.
4688 Sort messages by the value of their
4690 field, that is by the address of the sender.
4693 variable is set, the sender's real name (if any) is used.
4695 Sort the messages by their size.
4697 \*(OP Sort the message by their spam score, as has been classified by
4700 Sort the messages by their message status.
4702 Sort the messages by their subject.
4704 Create a threaded display.
4706 Sort messages by the value of their
4708 field, that is by the address of the recipient.
4711 variable is set, the recipient's real name (if any) is used.
4716 (so) The source command reads commands from the given file, which is
4717 subject to the usual filename expansions (see introductional words of
4719 If the given argument ends with a vertical bar
4721 then the argument will instead be interpreted as a shell command and
4722 \*(UA will read the output generated by it.
4725 cannot be used from within macros that execute as
4726 .Va folder-hook Ns s
4729 i.e., it can only be called from macros that were
4736 (beside not supporting pipe syntax aka shell command input) is that
4737 this command will not generate an error if the given file argument
4738 cannot be opened successfully.
4739 This can matter in, e.g., resource files, since loading of those is
4740 stopped when an error is encountered.
4744 \*(OP Takes a list of messages and clears their
4750 \*(OP Takes a list of messages and causes the
4752 to forget it has ever used them to train its Bayesian filter.
4753 Unless otherwise noted the
4755 flag of the message is inspected to chose whether a message shall be
4763 \*(OP Takes a list of messages and informs the Bayesian filter of the
4767 This also clears the
4769 flag of the messages in question.
4773 \*(OP Takes a list of messages and rates them using the configured
4774 .Va spam-interface ,
4775 without modifying the messages, but setting their
4777 flag as appropriate; because the spam rating headers are lost the rate
4778 will be forgotten once the mailbox is left.
4779 Refer to the manual section
4781 for the complete picture of spam handling in \*(UA.
4785 \*(OP Takes a list of messages and sets their
4791 \*(OP Takes a list of messages and informs the Bayesian filter of the
4797 flag of the messages in question.
4806 Create a threaded representation of the current folder,
4807 i.\|e. indent messages that are replies to other messages in the header
4808 display and change the
4810 command and the addressing modes such that they refer to messages in the
4812 Message numbers are the same as in unthreaded mode.
4816 a header summary in threaded order is also displayed.
4830 (to) Takes a message list and types out the first
4832 lines of each message on the users' terminal.
4833 The only header fields that are displayed are
4840 will instead honour configured lists).
4841 It is possible to apply compression to what is displayed by setting
4843 Messages are decrypted and converted to the terminal character set
4848 (tou) Takes a message list and marks the messages for saving in
4850 \*(UA deviates from the POSIX standard with this command,
4853 command will display the following message instead of the current one.
4859 but also displays out ignored header fields and all parts of MIME
4860 .Ql multipart/alternative
4865 (t) Takes a message list and types out each message on the users'
4871 For MIME multipart messages, all parts with a content type of
4875 are shown, the other are hidden except for their headers.
4876 Messages are decrypted and converted to the terminal character set
4881 Delete all given accounts.
4882 An error message is shown if a given account is not defined.
4885 will discard all existing accounts.
4889 (una) Takes a list of names defined by alias commands
4890 and discards the remembered groups of users.
4893 will discard all existing aliases.
4897 Takes a message list and marks each message as not having been answered.
4903 ing, specified by its context and input sequence, both of which may be
4904 specified as a wildcard (asterisk,
4908 will remove all bindings of all contexts.
4912 Only applicable to threaded mode.
4913 Takes a message list and makes the message and all replies to it visible
4914 in header summaries again.
4915 When a message becomes the current message,
4916 it is automatically made visible.
4917 Also when a message with collapsed replies is displayed,
4918 all of these are automatically uncollapsed.
4924 mapping for the given colour type (see
4926 for a list of types) and mapping; if the optional precondition argument
4927 is used then only the exact tuple of mapping and precondition is removed.
4930 will remove all mappings (no precondition allowed).
4932 .Sx "Coloured display"
4933 for the general picture.
4937 Deletes the custom headers given as arguments.
4940 will remove all custom headers.
4944 Undefine all given macros.
4945 An error message is shown if a given macro is not defined.
4948 will discard all existing macros.
4952 (u) Takes a message list and marks each message as not being deleted.
4956 Takes a message list and
4962 Takes a message list and marks each message as not being
4967 Removes the header field names from the list of ignored fields for the
4972 will remove all fields.
4976 Removes the header field names from the list of retained fields for the
4981 will remove all fields.
4985 Remove all the given command
4989 will remove all ghosts.
4993 Removes the header field names from the list of ignored fields.
4996 will remove all fields.
5000 Delete all given MIME types, e.g.,
5001 .Ql unmimetype text/plain
5002 will remove all registered specifications for the MIME type
5006 will discard all existing MIME types, just as will
5008 but which also reenables cache initialization via
5009 .Va mimetypes-load-control .
5013 Forget about all the given mailing lists.
5016 will remove all lists.
5021 .It Ic unmlsubscribe
5022 Remove the subscription attribute from all given mailing lists.
5025 will clear the attribute from all lists which have it set.
5036 Takes a message list and marks each message as not having been read.
5040 Removes the header field names from the list of retained fields.
5043 will remove all fields.
5047 Removes the header field names from the list of ignored fields for
5051 will remove all fields.
5055 Removes the header field names from the list of retained fields for
5059 will remove all fields.
5063 (uns) Takes a list of internal variable names and discards their
5064 remembered values; the reverse of
5071 Deletes the shortcut names given as arguments.
5074 will remove all shortcuts.
5078 Disable sorted or threaded mode
5084 return to normal message order and,
5088 displays a header summary.
5098 Decode the given URL-encoded string arguments and show the results.
5099 Note the resulting strings may not be valid in the current locale, see
5104 URL-encode the given arguments and show the results.
5105 Because the arguments effectively are in the character set of the
5106 current locale the results will vary accordingly unless the input solely
5107 consists of characters in the portable character set, see
5108 .Sx "Character sets" .
5112 Edit the values of or create the given variable(s) in the
5114 Boolean variables cannot be edited.
5118 This command produces the same output as the listing mode of
5122 ity adjustments, but only for the given variables.
5126 \*(OP Takes a message list and verifies each message.
5127 If a message is not a S/MIME signed message,
5128 verification will fail for it.
5129 The verification process checks if the message was signed using a valid
5131 if the message sender's email address matches one of those contained
5132 within the certificate,
5133 and if the message content has been altered.
5137 (v) Takes a message list and invokes the display editor on each message.
5138 Modified contents are discarded unless the
5144 (w) For conventional messages the body without all headers is written.
5145 The output is decrypted and converted to its native format as necessary.
5146 If the output file exists, the text is appended.
5147 If a message is in MIME multipart format its first part is written to
5148 the specified file as for conventional messages,
5149 and the user is asked for a filename to save each other part.
5150 For convience saving of each part may be skipped by giving an empty value;
5151 the same result can also be achieved by writing it to
5153 For the second and subsequent parts a leading
5155 character causes the part to be piped to the remainder of the user input
5156 interpreted as a shell command;
5157 otherwise the user input is expanded as usually for folders,
5158 e.g., tilde expansion is performed.
5159 In non-interactive mode, only the parts of the multipart message
5160 that have a filename given in the part header are written,
5161 the others are discarded.
5162 The original message is never marked for deletion in the originating
5165 the contents of the destination file are overwritten if the file
5167 No special handling of compressed files is performed.
5176 \*(UA presents message headers in windowfuls as described under the
5179 This command scrolls to the next window of messages.
5180 If an argument is given, it specifies the window to use.
5181 A number prefixed by
5185 indicates that the window is calculated in relation to the current position.
5186 A number without a prefix specifies an absolute window number,
5189 lets \*(UA scroll to the last window of messages.
5195 but scrolls to the next or previous window that contains at least one
5204 .\" .Sh TILDE ESCAPES {{{
5207 Here is a summary of the tilde escapes,
5208 which are used to perform special functions when composing messages.
5209 Tilde escapes are only recognized at the beginning of lines.
5212 is somewhat of a misnomer since the actual escape character can be
5213 changed by adjusting the option
5216 .Bl -tag -width ".Ic __ filename"
5219 Insert the string of text in the message prefaced by a single
5221 (If the escape character has been changed,
5222 that character must be doubled
5223 in order to send it at the beginning of a line.)
5226 .It Ic ~! Ar command
5227 Execute the indicated shell
5229 then return to the message.
5233 Same effect as typing the end-of-file character.
5236 .It Ic ~: Ar \*(UA-command Ns \0or Ic ~_ Ar \*(UA-command
5237 Execute the given \*(UA command.
5238 Not all commands, however, are allowed.
5242 Write a summary of command escapes.
5245 .It Ic ~< Ar filename
5250 .It Ic ~<! Ar command
5252 is executed using the shell.
5253 Its standard output is inserted into the message.
5256 .It Ic ~@ Op Ar filename...
5257 With no arguments, edit the attachment list interactively.
5258 If an attachment's file name is left empty,
5259 that attachment is deleted from the list.
5260 When the end of the attachment list is reached,
5261 \*(UA will ask for further attachments until an empty name is given.
5262 If a given file name solely consists of the number sign
5264 followed by a valid message number of the currently active mailbox, then
5265 the given message is attached as a MIME
5267 and the rest of this section does not apply.
5269 If character set conversion has been compiled into \*(UA, then this mode
5270 gives the user the option to specify input and output character sets,
5271 unless the file extension indicates binary content, in which case \*(UA
5272 asks whether this step shall be skipped for the attachment in question.
5273 If not skipped, then the charset that succeeds to represent the
5274 attachment data will be used in the
5276 MIME parameter of the mail message:
5278 .Bl -bullet -compact
5280 If input and output character sets are specified, then the conversion is
5281 performed on the fly.
5282 The user will be asked repeatedly until the desired conversion succeeds.
5284 If only an output character set is specified, then the input is assumed
5287 charset and will be converted to the given output charset on the fly.
5288 The user will be asked repeatedly until the desired conversion succeeds.
5290 If no character sets are specified at all then the algorithm that is
5291 documented in the section
5292 .Sx "Character sets"
5293 is applied, but directly and on the fly.
5294 The user will be asked repeatedly until the desired conversion succeeds.
5296 Finally, if an input-, but no output character set is specified, then no
5297 conversion is ever performed, but the
5299 MIME parameter value will still be set to the user input.
5301 The character set selection loop can be left by typing
5303 i.e., causing an interrupt.
5304 .\" \*(OU next sentence
5305 Note that before \*(UA version 15.0 this terminates the entire
5306 current attachment selection, not only the character set selection.
5309 Without character set conversion support, \*(UA will ask for the input
5310 character set only, and it'll set the
5312 MIME parameter value to the given input, if any;
5313 if no user input is seen then the
5315 character set will be used for the parameter value instead.
5316 Note that the file extension check isn't performed in this mode, since
5317 no conversion will take place anyway.
5319 Note that in non-interactive mode, for reproduceabilities sake, there
5320 will always be two questions for each attachment, regardless of whether
5321 character set conversion is available and what the file extension is.
5322 The first asks for the filename, and the second asks for the input
5323 character set to be passed through to the corresponding MIME parameter;
5324 no conversion will be tried if there is input to the latter question,
5325 otherwise the usual conversion algorithm, as above, is applied.
5326 For message attachments, the answer to the second question is completely
5331 arguments are specified for the
5333 command they are treated as a file list of
5335 -style quoted arguments, optionally also separated by commas, which are
5336 expanded and then appended to the existing list of message attachments.
5337 Message attachments can only be added via the first method.
5338 In this mode the (text) attachments are assumed to be in
5340 encoding, and will be evaluated as documented in the section
5341 .Sx "Character sets" .
5345 Inserts the string contained in the
5348 .Ql Ic ~i Ns \0Sign ) .
5349 The escape sequences tabulator
5357 Inserts the string contained in the
5360 .Ql Ic ~i Ns \0sign ) .
5361 The escape sequences tabulator
5368 .It Ic ~b Ar name ...
5369 Add the given names to the list of blind carbon copy recipients.
5372 .It Ic ~c Ar name ...
5373 Add the given names to the list of carbon copy recipients.
5377 Read the file specified by the
5379 variable into the message.
5383 Invoke the text editor on the message collected so far.
5384 After the editing session is finished,
5385 the user may continue appending text to the message.
5388 .It Ic ~F Ar messages
5389 Read the named messages into the message being sent, including all
5390 message headers and MIME parts.
5391 If no messages are specified, read in the current message.
5394 .It Ic ~f Ar messages
5395 Read the named messages into the message being sent.
5396 If no messages are specified, read in the current message.
5400 lists are used to modify the message headers.
5401 For MIME multipart messages,
5402 only the first displayable part is included.
5406 Edit the message header fields
5411 by typing each one in turn and allowing the user to edit the field.
5412 The default values for these fields originate from the
5420 Edit the message header fields
5426 by typing each one in turn and allowing the user to edit the field.
5429 .It Ic ~i Ar variable
5430 Insert the value of the specified variable into the message,
5431 adding a newline character at the end.
5432 The message remains unaltered if the variable is unset or empty.
5433 The escape sequences tabulator
5440 .It Ic ~M Ar messages
5441 Read the named messages into the message being sent,
5444 If no messages are specified, read the current message.
5447 .It Ic ~m Ar messages
5448 Read the named messages into the message being sent,
5451 If no messages are specified, read the current message.
5455 lists are used to modify the message headers.
5456 For MIME multipart messages,
5457 only the first displayable part is included.
5461 Display the message collected so far,
5462 prefaced by the message header fields
5463 and followed by the attachment list, if any.
5467 Abort the message being sent,
5468 copying it to the file specified by the
5475 .It Ic ~R Ar filename
5476 Read the named file into the message, indented by
5480 .It Ic ~r Ar filename
5481 Read the named file into the message.
5485 Cause the named string to become the current subject field.
5488 .It Ic ~t Ar name ...
5489 Add the given name(s) to the direct recipient list.
5492 .It Ic ~U Ar messages
5493 Read in the given / current message(s) excluding all headers, indented by
5497 .It Ic ~u Ar messages
5498 Read in the given / current message(s), excluding all headers.
5502 Invoke an alternate editor (defined by the
5504 option) on the message collected so far.
5505 Usually, the alternate editor will be a screen editor.
5506 After the editor is quit,
5507 the user may resume appending text to the end of the message.
5510 .It Ic ~w Ar filename
5511 Write the message onto the named file.
5513 the message is appended to it.
5519 except that the message is not saved at all.
5522 .It Ic ~| Ar command
5523 Pipe the message through the specified filter command.
5524 If the command gives no output or terminates abnormally,
5525 retain the original text of the message.
5528 is often used as a rejustifying filter.
5533 .\" .Sh INTERNAL VARIABLES {{{
5534 .Sh "INTERNAL VARIABLES"
5536 Internal \*(UA variables are controlled via the
5540 commands; prefixing a variable name with the string
5544 has the same effect as using
5550 Creation or editing of variables can be performed in the
5555 will give more insight on the given variable(s), and
5557 when called without arguments, will show a listing of all variables.
5558 Some well-known variables will also become inherited from the
5561 implicitly, others can be explicitly imported with the command
5563 and henceforth share the said properties.
5566 Two different kind of internal variables exist.
5567 There are boolean variables, which can only be in one of the two states
5571 and value variables with a(n optional) string value.
5572 For the latter proper quoting is necessary upon assignment time, the
5573 introduction of the section
5575 documents the supported quoting rules.
5577 .Bd -literal -offset indent
5578 wysh set one=val\e 1 two="val 2" \e
5579 three='val "3"' four=$'val \e'4\e''
5580 varshow one two three four
5581 unset one two three four
5585 Dependent upon the actual option the string values will be interpreted
5586 as numbers, colour names, normal text etc., but there also exists
5587 a special kind of string value, the
5588 .Dq boolean string ,
5589 which must either be a decimal integer (in which case
5593 and any other value is true) or any of the (case-insensitive) strings
5599 for a false boolean and
5605 for a true boolean; a special kind of boolean string is the
5607 which is a boolean string that can optionally be prefixed with the
5608 (case-insensitive) term
5612 which causes prompting of the user in interactive mode, with the given
5613 boolean as the default value.
5615 .\" .Ss "Initial settings" {{{
5616 .\" (Keep in SYNC: ./nail.h:okeys, ./nail.rc, ./nail.1:"Initial settings")
5617 .Ss "Initial Settings"
5619 The standard POSIX 2008/Cor 1-2013 mandates the following initial
5625 .Pf no Va autoprint ,
5639 .Pf no Va ignoreeof ,
5641 .Pf no Va keepsave ,
5643 .Pf no Va outfolder ,
5648 (note that \*(UA deviates from the standard by using
5652 special prompt escape results in
5660 .Pf no Va sendwait ,
5669 Notes: \*(UA doesn't support the
5671 variable \(en use command line options or
5673 to pass options through to a
5675 And the default global
5677 file (which is loaded unless the
5679 command line flag has been used or the
5680 .Ev NAIL_NO_SYSTEM_RC
5681 environment variable is set) bends those initial settings a bit, e.g.,
5682 it sets the variables
5687 to name a few, calls
5689 etc., and should thus be taken into account.
5692 .\" .Ss "Variables" {{{
5695 .Bl -tag -width ".It Va _utoprin_"
5697 .It Va add-file-recipients
5698 \*(BO When file or pipe recipients have been specified,
5699 mention them in the corresponding address fields of the message instead
5700 of silently stripping them from their recipient list.
5701 By default such addressees are not mentioned.
5705 \*(BO Causes only the local part to be evaluated
5706 when comparing addresses.
5710 \*(BO Causes messages saved in
5712 to be appended to the end rather than prepended.
5713 This should always be set.
5717 \*(BO Causes \*(UA to prompt for the subject of each message sent.
5718 If the user responds with simply a newline,
5719 no subject field will be sent.
5723 \*(BO Causes the prompts for
5727 lists to appear after the message has been edited.
5731 \*(BO If set, \*(UA asks for files to attach at the end of each message,
5732 shall the list be found empty at that time.
5733 An empty line finalizes the list.
5737 \*(BO Causes the user to be prompted for carbon copy recipients
5738 (at the end of each message if
5742 are set) shall the list be found empty (at that time).
5743 An empty line finalizes the list.
5747 \*(BO Causes the user to be prompted for blind carbon copy
5748 recipients (at the end of each message if
5752 are set) shall the list be found empty (at that time).
5753 An empty line finalizes the list.
5757 \*(BO\*(OP Causes the user to be prompted if the message is to be
5758 signed at the end of each message.
5761 variable is ignored when this variable is set.
5765 \*(BO Alternative name for
5772 .It Va attachment-ask-content-description , \
5773 attachment-ask-content-disposition , \
5774 attachment-ask-content-id , \
5775 attachment-ask-content-type
5776 \*(BO If set then the user will be prompted for some attachment
5777 information when editing the attachment list.
5778 It is advisable to not use these but for the first of the variables;
5779 even for that it has to be noted that the data is used
5785 A sequence of characters to display in the
5789 as shown in the display of
5791 each for one type of messages (see
5792 .Sx "Message states" ) ,
5793 with the default being
5796 .Ql NU\ \ *HMFAT+\-$~
5799 variable is set, in the following order:
5801 .Bl -tag -compact -offset indent -width ".It Ql _"
5823 start of a collapsed thread.
5825 an uncollapsed thread (TODO ignored for now).
5829 classified as possible spam.
5835 Specifies a list of recipients to which a blind carbon copy of each
5836 outgoing message will be sent automatically.
5840 Specifies a list of recipients to which a carbon copy of each outgoing
5841 message will be sent automatically.
5845 \*(BO Causes threads to be collapsed automatically when threaded mode
5852 \*(BO Causes the delete command to behave like
5854 thus, after deleting a message the next one will be typed automatically.
5858 \*(BO\*(OB Causes threaded mode (see the
5860 command) to be entered automatically when a folder is opened.
5862 .Ql autosort=thread .
5866 Causes sorted mode (see the
5868 command) to be entered automatically with the value of this option as
5869 sorting method when a folder is opened, e.g.,
5870 .Ql set autosort=thread .
5874 \*(BO Enables the substitution of
5876 by the contents of the last command line in shell escapes.
5879 .It Va batch-exit-on-error
5880 \*(BO If the batch mode has been enabled via the
5882 command line option, then this variable will be consulted whenever \*(UA
5883 completes one operation (returns to the command prompt); if it is set
5884 then \*(UA will terminate if the last operation generated an error.
5888 \*(OP Terminals generate multi-byte sequences for certain forms of
5889 input, for example for function and other special keys.
5890 Some terminals however do not write these multi-byte sequences as
5891 a whole, but byte-by-byte, and the latter is what \*(UA actually reads.
5892 This variable specifies the timeout in milliseconds that the MLE (see
5893 .Sx "On terminal control and line editor" )
5894 waits for more bytes to arrive unless it considers a sequence
5900 \*(BO Causes automatic display of a header summary after executing a
5902 command, and thus complements the standard variable
5904 which controls header summary display on program startup.
5905 It is only meaningful if
5911 \*(BO Sets some cosmetical features to traditional BSD style;
5912 has the same affect as setting
5914 and all other variables prefixed with
5916 it also changes the meaning of the \*(UA specific
5919 escape sequence and changes behaviour of
5921 (which doesn't exist in BSD).
5925 \*(BO Changes the letters shown in the first column of a header
5926 summary to traditional BSD style.
5930 \*(BO Changes the display of columns in a header summary to traditional
5935 \*(BO Changes some informational messages to traditional BSD style.
5941 field to appear immediately after the
5943 field in message headers and with the
5945 .Sx "TILDE ESCAPES" .
5949 The value that should appear in the
5953 MIME header fields when no character set conversion of the message data
5955 This defaults to US-ASCII, and the chosen character set should be
5956 US-ASCII compatible.
5960 \*(OP The default 8-bit character set that is used as an implicit last
5961 member of the variable
5963 This defaults to UTF-8.
5964 If no character set conversion capabilities are available in \*(UA then
5965 the only supported character set is
5967 Refer to the section
5968 .Sx "Character sets"
5969 for the complete picture of character set conversion in \*(UA.
5972 .It Va charset-unknown-8bit
5973 \*(OP RFC 1428 specifies conditions when internet mail gateways shall
5975 the content of a mail message by using a character set with the name
5977 Because of the unclassified nature of this character set \*(UA will not
5978 be capable to convert this character set to any other character set.
5979 If this variable is set any message part which uses the character set
5981 is assumed to really be in the character set given in the value,
5982 otherwise the (final) value of
5984 is used for this purpose.
5986 This variable will also be taken into account if a MIME type (see
5987 .Sx "The mime.types files" )
5988 of a MIME message part that uses the
5990 character set is forcefully treated as text.
5994 The default value for the
5999 .It Va colour-disable
6000 \*(BO\*(OP Forcefully disable usage of colours.
6001 Also see the section
6002 .Sx "Coloured display" .
6006 \*(BO\*(OP Whether colour shall be used for output that is paged through
6008 Note that pagers may need special flags, e.g.,
6016 in order to support colours.
6017 Often doing manual adjustments is unnecessary since \*(UA may perform
6018 adjustments dependend on the value of the environment variable
6020 (see there for more).
6024 In a(n interactive) terminal session, then if this valued option is set
6025 it'll be used as a threshold to determine how many lines the given
6026 output has to span before it will be displayed via the configured
6030 can be forced by setting this to the value
6032 setting it without a value will deduce the current height of the
6033 terminal screen to compute the treshold (see
6041 \*(OB A variable counterpart of the
6043 command (see there for documentation), interpreted as a comma-separated
6044 list of custom headers to be injected, to include commas in the header
6045 bodies escape them with reverse solidus, e.g.:
6047 .Dl set customhdr='Hdr1: Body1-1\e, Body1-2, Hdr2: Body2'
6053 the message date, if any is to be displayed according to the format of
6055 is by default taken from the
6057 line of the message.
6058 If this variable is set the date as given in the
6060 header field is used instead, converted to local time.
6061 To control the display format of the date assign a valid
6066 format should not be used, because \*(UA doesn't take embedded newlines
6067 into account when calculating how many lines fit onto the screen.)
6069 .Va datefield-markout-older .
6072 .It Va datefield-markout-older
6073 This option, when set in addition to
6077 messages (concept is rather comparable to the
6079 option of the POSIX utility
6081 The content interpretation is identical to
6086 \*(BO Enables debug messages and obsoletion warnings, disables the
6087 actual delivery of messages and also implies
6093 .It Va disposition-notification-send
6095 .Ql Disposition-Notification-To:
6096 header (RFC 3798) with the message.
6100 .\" TODO .It Va disposition-notification-send-HOST
6102 .\".Va disposition-notification-send
6103 .\" for SMTP accounts on a specific host.
6104 .\" TODO .It Va disposition-notification-send-USER@HOST
6106 .\".Va disposition-notification-send
6107 .\"for a specific account.
6111 \*(BO When dot is set, a period
6113 on a line by itself during message input in (interactive) compose mode
6114 will be treated as end-of-message (in addition to the normal end-of-file
6123 .It Va dotlock-ignore-error
6124 \*(BO\*(OP Synchronization of mailboxes which \*(UA treats as system
6125 mailboxes (see the command
6127 will be protected with so-called dotlock files\(emthe traditional mail
6128 spool file locking method\(emin addition to system file locking.
6129 Because \*(UA ships with a privilege-separated dotlock creation program
6130 that should always be able to create such a dotlock file there is no
6131 good reason to ignore dotlock file creation errors, and thus these are
6132 fatal unless this variable is set.
6136 \*(BO If this variable is set then the editor is started automatically
6137 when a message is composed in interactive mode, as if the
6143 variable is implied for this automatically spawned editor session.
6147 \*(BO When a message is edited while being composed,
6148 its header is included in the editable text.
6158 fields are accepted within the header, other fields are ignored.
6162 \*(BO When entering interactive mode \*(UA normally writes
6163 .Dq \&No mail for user
6164 and exits immediately if a mailbox is empty or doesn't exist.
6165 If this option is set \*(UA starts even with an empty or nonexistent
6166 mailbox (the latter behaviour furtherly depends upon
6172 Suggestion for the MIME encoding to use in outgoing text messages
6174 Valid values are the default
6175 .Ql quoted-printable ,
6180 may cause problems when transferring mail messages over channels that
6181 are not ESMTP (RFC 1869) compliant.
6182 If there is no need to encode a message,
6184 transfer mode is always used regardless of this variable.
6185 Binary data is always encoded as
6190 If defined, the first character of this option
6191 gives the character to use in place of
6194 .Sx "TILDE ESCAPES" .
6198 If not set then file and command pipeline targets are not allowed,
6199 and any such address will be filtered out, giving a warning message.
6200 If set without a value then all possible recipient address
6201 specifications will be accepted \(en see the section
6202 .Sx "On sending mail, and non-interactive mode"
6204 To accept them, but only in interactive mode, or when tilde commands
6205 were enabled explicitly by using one of the command line options
6209 set this to the (case-insensitive) value
6211 (note right now this is actually like setting
6212 .Ql restrict,-all,+name,+addr ) .
6214 In fact the value is interpreted as a comma-separated list of values.
6217 then the existence of disallowed specifications is treated as a hard
6218 send error instead of only filtering them out.
6219 The remaining values specify whether a specific type of recipient
6220 address specification is allowed (optionally indicated by a plus sign
6222 prefix) or disallowed (prefixed with a hyphen
6226 addresses all possible address specifications,
6230 command pipeline targets,
6232 plain user names and (MTA) aliases (\*(OB
6234 may be used as an alternative syntax to
6239 These kind of values are interpreted in the given order, so that
6240 .Ql restrict,\:fail,\:+file,\:-all,\:+addr
6241 will cause hard errors for any non-network address recipient address
6242 unless \*(UA is in interactive mode or has been started with the
6246 command line option; in the latter case(s) any address may be used, then.
6250 Unless this variable is set additional
6252 (Mail-Transfer-Agent)
6253 arguments from the command line, as can be given after a
6255 separator, are ignored due to safety reasons.
6256 However, if set to the special (case-insensitive) value
6258 then the presence of additional MTA arguments is treated as a hard
6259 error that causes \*(UA to exit with failure status.
6260 A lesser strict variant is the otherwise identical
6262 which does accept such arguments in interactive mode, or if tilde
6263 commands were enabled explicitly by using one of the command line options
6270 \*(RO Information on the features compiled into \*(UA \(en the content
6271 of this variable is identical to the output of the command
6276 \*(BO This option reverses the meanings of a set of reply commands,
6277 turning the lowercase variants, which by default address all recipients
6278 included in the header of a message
6279 .Pf ( Ic reply , respond , followup )
6280 into the uppercase variants, which by default address the sender only
6281 .Pf ( Ic Reply , Respond , Followup )
6284 .Ic replysender , respondsender , followupsender
6286 .Ic replyall , respondall , followupall
6287 are not affected by the current setting of
6292 .It Va file-hook-load-EXTENSION , file-hook-save-EXTENSION
6293 It is possible to install file hooks which will be used by the
6295 command in order to be able to transparently handle (through an
6296 intermediate temporary file) files with specific
6298 s: the variable values can include shell snippets and are expected to
6299 write data to standard output / read data from standard input,
6301 \*(ID The variables may not be changed while there is a mailbox
6303 .Bd -literal -offset indent
6304 set file-hook-load-xy='echo >&2 XY-LOAD; gzip -cd' \e
6305 file-hook-save-xy='echo >&2 XY-SAVE; gzip -c' \e
6306 record=+null-sent.xy
6311 The default path under which mailboxes are to be saved:
6312 file names that begin with the plus-sign
6314 will be expanded by prefixing them with the value of this variable.
6315 The same special syntax conventions as documented for the
6317 command may be used; if the non-empty value doesn't start with a solidus
6321 will be prefixed automatically.
6322 If unset or the empty string any
6324 prefixing file names will remain unexpanded.
6328 This variable can be set to the name of a
6330 macro which will be called whenever a
6333 The macro will also be invoked when new mail arrives,
6334 but message lists for commands executed from the macro
6335 only include newly arrived messages then.
6337 are activated by default in a folder hook, causing the covered settings
6338 to be reverted once the folder is left again.
6341 Macro behaviour, including option localization, will change in v15.
6342 Please be aware of that and possibly embed a version check in a resource
6346 .It Va folder-hook-FOLDER
6351 Unlike other folder specifications, the fully expanded name of a folder,
6352 without metacharacters, is used to avoid ambiguities.
6353 However, if the mailbox resides under
6357 specification is tried in addition, e.g., if
6361 (and thus relative to the user's home directory) then
6362 .Pa /home/usr1/mail/sent
6364 .Ql folder-hook-/home/usr1/mail/sent
6365 first, but then followed by
6366 .Ql folder-hook-+sent .
6370 \*(BO Controls whether a
6371 .Ql Mail-Followup-To:
6372 header is generated when sending messages to known mailing lists.
6374 .Va followup-to-honour
6376 .Ic mlist , mlsubscribe , reply
6381 .It Va followup-to-honour
6383 .Ql Mail-Followup-To:
6384 header is honoured when group-replying to a message via
6388 This is a quadoption; if set without a value it defaults to
6398 .It Va forward-as-attachment
6399 \*(BO Original messages are normally sent as inline text with the
6402 and only the first part of a multipart message is included.
6403 With this option messages are sent as unmodified MIME
6405 attachments with all of their parts included.
6409 The address (or a list of addresses) to put into the
6411 field of the message header, quoting RFC 5322:
6412 the author(s) of the message, that is, the mailbox(es) of the person(s)
6413 or system(s) responsible for the writing of the message.
6416 ing to messages these addresses are handled as if they were in the
6420 If the machine's hostname is not valid at the Internet (for example at
6421 a dialup machine) then either this variable or
6423 (\*(IN and with a defined SMTP protocol in
6426 adds even more fine-tuning capabilities),
6430 contains more than one address,
6433 variable is required (according to the standard RFC 5322).
6437 \*(BO When replying to or forwarding a message \*(UA normally removes
6438 the comment and name parts of email addresses.
6439 If this variable is set such stripping is not performed,
6440 and comments, names etc. are retained.
6444 The string to put before the text of a message with the
6448 .Va forward-as-attachment
6451 .Dq -------- Original Message --------
6452 if unset; No heading is put if it is set to the empty string.
6456 \*(BO Causes the header summary to be written at startup and after
6457 commands that affect the number of messages or the order of messages in
6458 the current folder; enabled by default.
6459 The command line option
6465 complements this and controls header summary display on folder changes.
6470 A format string to use for the summary of
6472 similar to the ones used for
6475 Format specifiers in the given string start with a percent character
6477 and may be followed by an optional decimal number indicating the field
6478 width \(em if that is negative, the field is to be left-aligned.
6479 Valid format specifiers are:
6482 .Bl -tag -compact -offset indent -width "_%%_"
6484 A plain percent character.
6487 a space character but for the current message
6489 for which it expands to
6493 a space character but for the current message
6495 for which it expands to
6498 \*(OP The spam score of the message, as has been classified via the
6501 Shows only a replacement character if there is no spam support.
6503 Message attribute character (status flag); the actual content can be
6507 The date when the message was received, or the date found in the
6511 variable is set (optionally to a date display format string).
6513 The indenting level in threaded mode.
6515 The address of the message sender.
6517 The message thread tree structure.
6518 (Note that this format doesn't support a field width.)
6520 The number of lines of the message, if available.
6524 The number of octets (bytes) in the message, if available.
6526 Message subject (if any).
6528 Message subject (if any) in double quotes.
6530 Message recipient flags: is the addressee of the message a known or
6531 subscribed mailing list \(en see
6536 The position in threaded/sorted order.
6540 .Ql %>\&%a\&%m\ %-18f\ %16d\ %4l/%\-5o\ %i%-s ,
6542 .Ql %>\&%a\&%m\ %20-f\ \ %16d\ %3l/%\-5o\ %i%-S
6553 .It Va headline-bidi
6554 Bidirectional text requires special treatment when displaying headers,
6555 because numbers (in dates or for file sizes etc.) will not affect the
6556 current text direction, in effect resulting in ugly line layouts when
6557 arabic or other right-to-left text is to be displayed.
6558 On the other hand only a minority of terminals is capable to correctly
6559 handle direction changes, so that user interaction is necessary for
6561 Note that extended host system support is required nonetheless, e.g.,
6562 detection of the terminal character set is one precondition;
6563 and this feature only works in an Unicode (i.e., UTF-8) locale.
6565 In general setting this variable will cause \*(UA to encapsulate text
6566 fields that may occur when displaying
6568 (and some other fields, like dynamic expansions in
6570 with special Unicode control sequences;
6571 it is possible to fine-tune the terminal support level by assigning
6573 no value (or any value other than
6578 will make \*(UA assume that the terminal is capable to properly deal
6579 with Unicode version 6.3, in which case text is embedded in a pair of
6580 U+2068 (FIRST STRONG ISOLATE) and U+2069 (POP DIRECTIONAL ISOLATE)
6582 In addition no space on the line is reserved for these characters.
6584 Weaker support is chosen by using the value
6586 (Unicode 6.3, but reserve the room of two spaces for writing the control
6587 sequences onto the line).
6592 select Unicode 1.1 support (U+200E, LEFT-TO-RIGHT MARK); the latter
6593 again reserves room for two spaces in addition.
6597 \*(OP If a line editor is available then this can be set to
6598 name the (expandable) path of the location of a permanent history file.
6601 .It Va history-gabby
6602 \*(BO\*(OP Add more entries to the history as is normally done.
6605 .It Va history-gabby-persist
6606 \*(BO\*(OP \*(UA's own MLE will not save the additional
6608 entries in persistent storage unless this variable is set.
6609 On the other hand it will not loose the knowledge of whether
6610 a persistent entry was gabby or not.
6616 \*(OP If a line editor is available this value restricts the
6617 amount of history entries that are saved into a set and valid
6619 A value of less than 0 disables this feature;
6620 note that loading and incorporation of
6622 upon program startup can also be suppressed by doing this.
6623 If unset or 0, a default value will be used.
6624 Dependent on the available line editor this will also define the
6625 number of history entries in memory;
6626 it is also editor-specific whether runtime updates of this value will
6631 \*(BO This option is used to hold messages in the system
6633 box, and it is set by default.
6637 Use this string as hostname when expanding local addresses instead of
6638 the value obtained from
6647 Note that when SMTP transport is not used (via
6649 then it is normally the responsibility of the MTA to create these
6650 fields, \*(IN in conjunction with SMTP however
6652 also influences the results:
6653 you should produce some test messages with the desired combination of
6662 \*(BO\*(OP Can be used to turn off the automatic conversion of domain
6663 names according to the rules of IDNA (internationalized domain names
6665 Since the IDNA code assumes that domain names are specified with the
6667 character set, an UTF-8 locale charset is required to represent all
6668 possible international domain names (before conversion, that is).
6672 \*(BO Ignore interrupt signals from the terminal while entering
6673 messages; instead echo them as
6675 characters and discard the current line.
6679 \*(BO Ignore end-of-file conditions
6680 .Pf ( Ql control-D )
6681 in compose mode on message input and in interactive command input.
6682 If set an interactive command input session can only be left by
6683 explicitly using one of the commands
6687 and message input in compose mode can only be terminated by entering
6690 on a line by itself or by using the
6692 .Sx "TILDE ESCAPES" ;
6694 overrides a setting of
6706 option for indenting messages,
6707 in place of the normal tabulator character
6709 which is the default.
6710 Be sure to quote the value if it contains spaces or tabs.
6714 \*(BO If set, an empty mailbox file is not removed.
6715 This may improve the interoperability with other mail user agents
6716 when using a common folder directory, and prevents malicious users
6717 from creating fake mailboxes in a world-writable spool directory.
6718 Note this only applies to local regular (MBOX) files, other mailbox
6719 types will never be removed.
6722 .It Va keep-content-length
6723 \*(BO When (editing messages and) writing
6725 mailbox files \*(UA can be told to keep the
6729 header fields that some MUAs generate by setting this variable.
6730 Since \*(UA does neither use nor update these non-standardized header
6731 fields (which in itself shows one of their conceptual problems),
6732 stripping them should increase interoperability in between MUAs that
6733 work with with same mailbox files.
6734 Note that, if this is not set but
6735 .Va writebackedited ,
6736 as below, is, a possibly performed automatic stripping of these header
6737 fields already marks the message as being modified.
6741 \*(BO When a message is saved it is usually discarded from the
6742 originating folder when \*(UA is quit.
6743 Setting this option causes all saved message to be retained.
6746 .It Va line-editor-disable
6747 \*(BO Turn off any enhanced line editing capabilities (see
6748 .Sx "On terminal control and line editor"
6752 .It Va line-editor-no-defaults
6753 \*(BO\*(OP Do not establish any default key binding.
6757 \*(BO When a message is replied to and this variable is set,
6758 it is marked as having been answered.
6759 This mark has no technical meaning in the mail system;
6760 it just causes messages to be marked in the header summary,
6761 and makes them specially addressable.
6765 \*(BO \*(UA generates and expects RFC 4155 compliant MBOX text
6767 (With the restriction that RFC 4155 defines seven-bit clean data
6768 storage, but which can be overwritten by a contrary setting of
6770 Messages which are fetched over the network or from within already
6771 existing Maildir (or any non-MBOX) mailboxes may require so-called
6773 quoting (insertion of additional
6775 characters to prevent line content misinterpretation) to be applied in
6776 order to be storable in MBOX mailboxes, however, dependent on the
6777 circumspection of the message producer.
6778 E.g., \*(UA itself will, when newly generating messages, choose a
6779 .Pf Content-Transfer- Va encoding
6780 that prevents the necessity for such quoting \(en a necessary
6781 precondition to ensure message checksums won't change.
6783 By default \*(UA will perform this
6785 quoting in a way that results in a MBOX file that is compatible with
6786 the POSIX MBOX layout, which means that, in order not to exceed the
6787 capabilities of simple applications, many more
6789 lines get quoted (thus modified) than necessary according to RFC 4155.
6790 Set this option to instead generate MBOX files which comply to RFC 4155.
6794 \*(BO Internal development variable.
6797 .It Va message-id-disable
6798 \*(BO By setting this option the generation of
6800 can be completely suppressed, effectively leaving this task up to the
6802 (Mail-Transfer-Agent) or the SMTP server.
6803 (According to RFC 5321 your SMTP server is not required to add this
6804 field by itself, so you should ensure that it accepts messages without a
6808 .It Va message-inject-head
6809 A string to put at the beginning of each new message.
6810 The escape sequences tabulator
6817 .It Va message-inject-tail
6818 A string to put at the end of each new message.
6819 The escape sequences tabulator
6827 \*(BO Usually, when an
6829 expansion contains the sender, the sender is removed from the expansion.
6830 Setting this option suppresses these removals.
6835 option to be passed through to the
6837 (Mail-Transfer-Agent); though most of the modern MTAs no longer document
6838 this flag, no MTA is known which doesn't support it (for historical
6842 .It Va mime-allow-text-controls
6843 \*(BO When sending messages, each part of the message is MIME-inspected
6844 in order to classify the
6847 .Ql Content-Transfer-Encoding:
6850 that is required to send this part over mail transport, i.e.,
6851 a computation rather similar to what the
6853 command produces when used with the
6857 This classification however treats text files which are encoded in
6858 UTF-16 (seen for HTML files) and similar character sets as binary
6859 octet-streams, forcefully changing any
6864 .Ql application/octet-stream :
6865 If that actually happens a yet unset charset MIME parameter is set to
6867 effectively making it impossible for the receiving MUA to automatically
6868 interpret the contents of the part.
6870 If this option is set, and the data was unambiguously identified as text
6871 data at first glance (by a
6875 file extension), then the original
6877 will not be overwritten.
6880 .It Va mime-alternative-favour-rich
6881 \*(BO If this variable is set then rich MIME alternative parts (e.g.,
6882 HTML) will be preferred in favour of included plain text versions when
6883 displaying messages, provided that a handler exists which produces
6884 output that can be (re)integrated into \*(UA's normal visual display.
6885 (E.g., at the time of this writing some newsletters ship their full
6886 content only in the rich HTML part, whereas the plain text part only
6887 contains topic subjects.)
6890 .It Va mime-counter-evidence
6893 field is used to decide how to handle MIME parts.
6894 Some MUAs however don't use
6896 or a similar mechanism to correctly classify content, but simply specify
6897 .Ql application/octet-stream ,
6898 even for plain text attachments like
6900 If this variable is set then \*(UA will try to classify such MIME
6901 message parts on its own, if possible, for example via a possibly
6902 existent attachment filename.
6903 A non-empty value may also be given, in which case a number is expected,
6904 actually a carrier of bits.
6905 Creating the bit-carrying number is a simple addition:
6906 .Bd -literal -offset indent
6907 ? !echo Value should be set to $((2 + 4 + 8))
6908 Value should be set to 14
6911 .Bl -bullet -compact
6913 If bit two is set (2) then the detected
6915 content-type will be carried along with the message and be used for
6917 .Va pipe-TYPE/SUBTYPE
6918 is responsible for the MIME part, shall that question arise;
6919 when displaying such a MIME part the part-info will indicate the
6920 overridden content-type by showing a plus-sign
6923 If bit three is set (4) then the counter-evidence is always produced
6924 and a positive result will be used as the MIME type, even forcefully
6925 overriding the parts given MIME type.
6927 If bit four is set (8) then as a last resort the actual content of
6928 .Ql application/octet-stream
6929 parts will be inspected, so that data which looks like plain text can be
6934 .It Va mimetypes-load-control
6935 This option can be used to control which of the
6937 databases are loaded by \*(UA, as furtherly described in the section
6938 .Sx "The mime.types files" .
6941 is part of the option value, then the user's personal
6943 file will be loaded (if it exists); likewise the letter
6945 controls loading of the system wide
6946 .Pa /etc/mime.types ;
6947 directives found in the user file take precedence, letter matching is
6949 If this option is not set \*(UA will try to load both files.
6950 Incorporation of the \*(UA-builtin MIME types cannot be suppressed,
6951 but they will be matched last.
6953 More sources can be specified by using a different syntax: if the
6954 value string contains an equals sign
6956 then it is instead parsed as a comma-separated list of the described
6959 pairs; the given filenames will be expanded and loaded, and their
6960 content may use the extended syntax that is described in the section
6961 .Sx "The mime.types files" .
6962 Directives found in such files always take precedence (are prepended to
6963 the MIME type cache).
6968 To choose an alternate Mail-Transfer-Agent, set this option to either
6969 the full pathname of an executable (optionally prefixed with a
6971 protocol indicator), or \*(OPally a SMTP protocol URL, e.g., \*(IN
6973 .Dl smtps?://[user[:password]@]server[:port]
6976 .Ql [smtp://]server[:port] . )
6977 The default has been chosen at compie time.
6978 All supported data transfers are executed in child processes, which
6979 run asynchronously, and without supervision, unless either the
6984 If such a child receives a TERM signal, it will abort and
6991 For a file-based MTA it may be necessary to set
6993 in in order to choose the right target of a modern
6996 It will be passed command line arguments from several possible sources:
6999 if set, from the command line if given and the variable
7002 Argument processing of the MTA will be terminated with a
7007 The otherwise occurring implicit usage of the following MTA command
7008 line arguments can be disabled by setting the boolean option
7009 .Va mta-no-default-arguments
7010 (which will also disable passing
7014 (for not treating a line with only a dot
7016 character as the end of input),
7024 option is set); in conjunction with the
7026 command line option \*(UA will also pass
7032 \*(OP \*(UA can send mail over SMTP network connections to a single
7033 defined SMTP smarthost, the access URL of which has to be assigned to
7035 To use this mode it is helpful to read
7036 .Sx "On URL syntax and credential lookup" .
7037 It may be necessary to set the
7039 variable in order to use a specific combination of
7044 with some mail providers.
7047 .Bl -bullet -compact
7049 The plain SMTP protocol (RFC 5321) that normally lives on the
7050 server port 25 and requires setting the
7051 .Va smtp-use-starttls
7052 variable to enter a SSL/TLS encrypted session state.
7053 Assign a value like \*(IN
7054 .Ql smtp://[user[:password]@]server[:port]
7056 .Ql smtp://server[:port] )
7057 to choose this protocol.
7059 The so-called SMTPS which is supposed to live on server port 465
7060 and is automatically SSL/TLS secured.
7061 Unfortunately it never became a standardized protocol and may thus not
7062 be supported by your hosts network service database
7063 \(en in fact the port number has already been reassigned to other
7066 SMTPS is nonetheless a commonly offered protocol and thus can be
7067 chosen by assigning a value like \*(IN
7068 .Ql smtps://[user[:password]@]server[:port]
7070 .Ql smtps://server[:port] ) ;
7071 due to the mentioned problems it is usually necessary to explicitly
7076 Finally there is the SUBMISSION protocol (RFC 6409), which usually
7077 lives on server port 587 and is practically identically to the SMTP
7078 protocol from \*(UA's point of view beside that; it requires setting the
7079 .Va smtp-use-starttls
7080 variable to enter a SSL/TLS secured session state.
7081 Assign a value like \*(IN
7082 .Ql submission://[user[:password]@]server[:port]
7084 .Ql submission://server[:port] ) .
7089 .It Va mta-arguments
7090 Arguments to pass through to a file-based
7092 can be given via this variable, the content of which will be split up in
7093 a vector of arguments, to be joined onto other possible MTA options:
7095 .Dl set mta-arguments='-t -X \&"/tmp/my log\&"'
7098 .It Va mta-no-default-arguments
7099 \*(BO Unless this option is set \*(UA will pass some well known
7100 standard command line options to a file-based
7102 (Mail-Transfer-Agent), see there for more.
7106 Many systems use a so-called
7108 environment to ensure compatibility with
7110 This works by inspecting the name that was used to invoke the mail
7112 If this variable is set then the mailwrapper (the program that is
7113 actually executed when calling the file-based
7115 will treat its contents as that name.
7120 .It Va NAIL_EXTRA_RC
7121 The name of an optional startup file to be read last.
7122 This variable has an effect only if it is set in any of the
7123 .Sx "Resource files" ,
7124 it is not imported from the environment.
7125 Use this file for commands that are not understood by other POSIX
7130 .It Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup
7131 \*(BO\*(IN\*(OP Used to control usage of the users
7133 file for lookup of account credentials, as documented in the section
7134 .Sx "On URL syntax and credential lookup"
7138 .Sx "The .netrc file"
7139 documents the file format.
7151 then \*(UA will read the output of a shell pipe instead of the users
7153 file if this variable is set (to the desired shell command).
7154 This can be used to, e.g., store
7158 .Dl set netrc-pipe='gpg -qd ~/.netrc.pgp'
7162 If this variable has the value
7164 newly created local folders will be in Maildir format.
7168 Checks for new mail in the current folder each time the prompt is shown.
7169 A Maildir folder must be re-scanned to determine if new mail has arrived.
7170 If this variable is set to the special value
7172 then a Maildir folder will not be rescanned completely, but only
7173 timestamp changes are detected.
7177 .It Va on-compose-enter , on-compose-leave
7178 \*(ID Macro hooks which will be executed before compose mode is
7179 entered, and after composing has been finished, respectively.
7180 Please note that this interface is very likely to change in v15, and
7181 should therefore possibly even be seen as experimental.
7183 are by default enabled for these hooks, causing any setting to be
7184 forgotten after the message has been sent.
7185 The following variables will be set temporarily during execution of the
7188 .Bl -tag -compact -width ".It Va compose_subject"
7191 .It Va compose-sender
7193 .It Va compose-to , compose-cc , compose-bcc
7194 The list of receiver addresses as a space-separated list.
7195 .It Va compose-subject
7201 \*(BO Causes the filename given in the
7204 and the sender-based filenames for the
7208 commands to be interpreted relative to the directory given in the
7210 variable rather than to the current directory,
7211 unless it is set to an absolute pathname.
7215 \*(BO If set, each message feed through the command given for
7217 is followed by a formfeed character
7221 .It Va password-USER@HOST , password-HOST , password
7222 \*(IN Variable chain that sets a password, which is used in case none has
7223 been given in the protocol and account-specific URL;
7224 as a last resort \*(UA will ask for a password on the user's terminal if
7225 the authentication method requires a password.
7226 Specifying passwords in a startup file is generally a security risk;
7227 the file should be readable by the invoking user only.
7229 .It Va password-USER@HOST
7230 \*(OU (see the chain above for \*(IN)
7231 Set the password for
7235 If no such variable is defined for a host,
7236 the user will be asked for a password on standard input.
7237 Specifying passwords in a startup file is generally a security risk;
7238 the file should be readable by the invoking user only.
7242 \*(BO Send messages to the
7244 command without performing MIME and character set conversions.
7248 .It Va pipe-TYPE/SUBTYPE
7249 When a MIME message part of type
7251 (case-insensitive) is displayed or quoted,
7252 its text is filtered through the value of this variable interpreted as
7256 forces interpretation of the message part as plain text, e.g.,
7257 .Ql set pipe-application/xml=@
7258 will henceforth display XML
7260 (The same could also be achieved by adding a MIME type marker with the
7263 And \*(OPally MIME type handlers may be defined via
7264 .Sx "The Mailcap files"
7265 \(em corresponding flag strings are shown in parenthesis below.)
7270 can in fact be used to adjust usage and behaviour of a following shell
7271 command specification by appending trigger characters to it, e.g., the
7272 following hypothetical command specification could be used:
7273 .Bd -literal -offset indent
7274 set pipe-X/Y='@*!++=@vim ${NAIL_FILENAME_TEMPORARY}'
7278 .Bl -tag -compact -width ".It Ql __"
7280 Simply by using the special
7282 prefix the MIME type (shell command) handler will only be invoked to
7283 display or convert the MIME part if the message is addressed directly
7284 and alone by itself.
7285 Use this trigger to disable this and always invoke the handler
7286 .Pf ( Cd x-mailx-always ) .
7289 If set the handler will not be invoked when a message is to be quoted,
7290 but only when it will be displayed
7291 .Pf ( Cd x-mailx-noquote ) .
7294 The command will be run asynchronously, i.e., without blocking \*(UA,
7295 which may be a handy way to display a, e.g., PDF file while also
7296 continuing to read the mail message
7297 .Pf ( Cd x-mailx-async ) .
7298 Asynchronous execution implies
7302 The command must be run on an interactive terminal, \*(UA will
7303 temporarily release the terminal to it
7304 .Pf ( Cd needsterminal ) .
7305 This flag is mutual exclusive with
7307 will only be used in interactive mode and implies
7311 Request creation of a zero-sized temporary file, the absolute pathname
7312 of which will be made accessible via the environment variable
7313 .Ev NAIL_FILENAME_TEMPORARY
7314 .Pf ( Cd x-mailx-tmpfile ) .
7315 If this trigger is given twice then the file will be unlinked
7316 automatically by \*(UA when the command loop is entered again at latest
7317 .Pf ( Cd x-mailx-tmpfile-unlink ) .
7318 (Don't use this for asynchronous handlers.)
7321 Normally the MIME part content is passed to the handler via standard
7322 input; if this flag is set then the data will instead be written into
7323 .Ev NAIL_FILENAME_TEMPORARY
7324 .Pf ( Cd x-mailx-tmpfile-fill ) ,
7325 the creation of which is implied; note however that in order to cause
7326 deletion of the temporary file you still have to use two plus signs
7331 To avoid ambiguities with normal shell command content you can use
7332 another at-sign to forcefully terminate interpretation of remaining
7334 (Any character not in this list will have the same effect.)
7338 Some information about the MIME part to be displayed is embedded into
7339 the environment of the shell command:
7342 .Bl -tag -compact -width ".It Ev _AIL__ILENAME__ENERATED"
7345 The MIME content-type of the part, if known, the empty string otherwise.
7348 .It Ev NAIL_CONTENT_EVIDENCE
7350 .Va mime-counter-evidence
7351 includes the carry-around-bit (2), then this will be set to the detected
7352 MIME content-type; not only then identical to
7353 .Ev \&\&NAIL_CONTENT
7357 .It Ev NAIL_FILENAME
7358 The filename, if any is set, the empty string otherwise.
7361 .It Ev NAIL_FILENAME_GENERATED
7365 .It Ev NAIL_FILENAME_TEMPORARY
7366 If temporary file creation has been requested through the command prefix
7367 this variable will be set and contain the absolute pathname of the
7372 The temporary directory that \*(UA uses.
7373 Usually identical to
7375 but guaranteed to be set and usable by child processes;
7376 to ensure the latter condition for
7383 .It Va pipe-EXTENSION
7384 This is identical to
7385 .Va pipe-TYPE/SUBTYPE
7388 (normalized to lowercase using character mappings of the ASCII charset)
7389 names a file extension, e.g.,
7391 Handlers registered using this method take precedence.
7394 .It Va pop3-auth-USER@HOST , pop3-auth-HOST , pop3-auth
7395 \*(OP\*(IN Variable chain that sets the POP3 authentication method.
7396 The only possible value as of now is
7398 which is thus the default.
7401 .Mx Va pop3-bulk-load
7402 .It Va pop3-bulk-load-USER@HOST , pop3-bulk-load-HOST , pop3-bulk-load
7403 \*(BO\*(OP When accessing a POP3 server \*(UA loads the headers of
7404 the messages, and only requests the message bodies on user request.
7405 For the POP3 protocol this means that the message headers will be
7407 If this option is set then \*(UA will download only complete messages
7408 from the given POP3 server(s) instead.
7410 .Mx Va pop3-keepalive
7411 .It Va pop3-keepalive-USER@HOST , pop3-keepalive-HOST , pop3-keepalive
7412 \*(OP POP3 servers close the connection after a period of inactivity;
7413 the standard requires this to be at least 10 minutes,
7414 but practical experience may vary.
7415 Setting this variable to a numeric value greater than
7419 command to be sent each value seconds if no other operation is performed.
7422 .It Va pop3-no-apop-USER@HOST , pop3-no-apop-HOST , pop3-no-apop
7423 \*(BO\*(OP Unless this variable is set the
7425 authentication method will be used when connecting to a POP3 server that
7429 is that the password is not sent in clear text over the wire and that
7430 only a single packet is sent for the user/password tuple.
7432 .Va pop3-no-apop-HOST
7435 .Mx Va pop3-use-starttls
7436 .It Va pop3-use-starttls-USER@HOST , pop3-use-starttls-HOST , pop3-use-starttls
7437 \*(BO\*(OP Causes \*(UA to issue a
7439 command to make an unencrypted POP3 session SSL/TLS encrypted.
7440 This functionality is not supported by all servers,
7441 and is not used if the session is already encrypted by the POP3S method.
7443 .Va pop3-use-starttls-HOST
7447 .It Va print-alternatives
7448 \*(BO When a MIME message part of type
7449 .Ql multipart/alternative
7450 is displayed and it contains a subpart of type
7452 other parts are normally discarded.
7453 Setting this variable causes all subparts to be displayed,
7454 just as if the surrounding part was of type
7455 .Ql multipart/mixed .
7459 The string shown when a command is accepted.
7460 Prompting may be prevented by setting this to the null string
7462 .Pf no Va prompt ) .
7463 If a value is assigned the following \*(UA specific additional sequences
7470 is set, in which case it expands to
7474 is the default value of
7477 which will expand to
7479 if the last command failed and to
7483 which will expand to the name of the currently active
7485 if any, and to the empty string otherwise, and
7487 which will expand to the name of the currently active mailbox.
7488 (Note that the prompt buffer is size-limited, excess is cut off.)
7494 to encapsulate the expansions of the
7498 escape sequences as necessary to correctly display bidirectional text,
7499 this is not true for the final string that makes up
7501 as such, i.e., real BIDI handling is not supported.
7505 \*(BO Suppresses the printing of the version when first invoked.
7509 If set, \*(UA starts a replying message with the original message
7510 prefixed by the value of the variable
7512 Normally, a heading consisting of
7513 .Dq Fromheaderfield wrote:
7514 is put before the quotation.
7519 variable, this heading is omitted.
7522 is assigned, the headers selected by the
7523 .Ic ignore Ns / Ns Ic retain
7524 commands are put above the message body,
7527 acts like an automatic
7533 is assigned, all headers are put above the message body and all MIME
7534 parts are included, making
7536 act like an automatic
7539 .Va quote-as-attachment .
7542 .It Va quote-as-attachment
7543 \*(BO Add the original message in its entirety as a
7545 MIME attachment when replying to a message.
7546 Note this works regardless of the setting of
7551 \*(OP Can be set in addition to
7553 Setting this turns on a more fancy quotation algorithm in that leading
7554 quotation characters are compressed and overlong lines are folded.
7556 can be set to either one or two (space separated) numeric values,
7557 which are interpreted as the maximum (goal) and the minimum line length,
7558 respectively, in a spirit rather equal to the
7560 program, but line-, not paragraph-based.
7561 If not set explicitly the minimum will reflect the goal algorithmically.
7562 The goal can't be smaller than the length of
7564 plus some additional pad.
7565 Necessary adjustments take place silently.
7568 .It Va recipients-in-cc
7569 \*(BO On group replies, specify only the sender of the original mail in
7571 and mention the other recipients in the secondary
7573 By default all recipients of the original mail will be addressed via
7578 If defined, gives the pathname of the folder used to record all outgoing
7580 If not defined, then outgoing mail is not saved.
7581 When saving to this folder fails the message is not sent,
7582 but instead saved to
7586 .It Va record-resent
7587 \*(BO If both this variable and the
7594 commands save messages to the
7596 folder as it is normally only done for newly composed messages.
7599 .It Va reply-in-same-charset
7600 \*(BO If this variable is set \*(UA first tries to use the same
7601 character set of the original message for replies.
7602 If this fails, the mechanism described in
7603 .Sx "Character sets"
7604 is evaluated as usual.
7607 .It Va reply_strings
7608 Can be set to a comma-separated list of (case-insensitive according to
7609 ASCII rules) strings which shall be recognized in addition to the
7612 reply message indicators \(en builtin are
7614 which is mandated by RFC 5322, as well as the german
7619 A list of addresses to put into the
7621 field of the message header.
7622 Members of this list are handled as if they were in the
7627 .It Va reply-to-honour
7630 header is honoured when replying to a message via
7634 This is a quadoption; if set without a value it defaults to
7638 .It Va rfc822-body-from_
7639 \*(BO This variable can be used to force displaying a so-called
7641 line for messages that are embedded into an envelope mail via the
7643 MIME mechanism, for more visual convenience.
7647 \*(BO Enable saving of (partial) messages in
7649 upon interrupt or delivery error.
7653 The number of lines that represents a
7662 line display and scrolling via
7664 If this variable is not set \*(UA falls back to a calculation based upon
7665 the detected terminal window size and the baud rate: the faster the
7666 terminal, the more will be shown.
7667 Overall screen dimensions and pager usage is influenced by the
7668 environment variables
7676 .It Va searchheaders
7677 \*(BO Expand message-list specifiers in the form
7679 to all messages containing the substring
7683 The string search is case insensitive.
7687 \*(OP A comma-separated list of character set names that can be used in
7688 outgoing internet mail.
7689 The value of the variable
7691 is automatically appended to this list of character-sets.
7692 If no character set conversion capabilities are compiled into \*(UA then
7693 the only supported charset is
7696 .Va sendcharsets-else-ttycharset
7697 and refer to the section
7698 .Sx "Character sets"
7699 for the complete picture of character set conversion in \*(UA.
7702 .It Va sendcharsets-else-ttycharset
7703 \*(BO\*(OP If this variable is set, but
7705 is not, then \*(UA acts as if
7707 had been set to the value of the variable
7709 In effect this combination passes through the message data in the
7710 character set of the current locale (given that
7712 hasn't been set manually), i.e., without converting it to the
7714 fallback character set.
7715 Thus, mail message text will be in ISO-8859-1 encoding when send from
7716 within a ISO-8859-1 locale, and in UTF-8 encoding when send from within
7718 If no character set conversion capabilities are available in \*(UA then
7719 the only supported character set is
7724 An address that is put into the
7726 field of outgoing messages, quoting RFC 5322: the mailbox of the agent
7727 responsible for the actual transmission of the message.
7728 This field should normally not be used unless the
7730 field contains more than one address, on which case it is required.
7733 address is handled as if it were in the
7739 \*(OB Predecessor of
7743 .It Va sendmail-arguments
7744 \*(OB Predecessor of
7748 .It Va sendmail-no-default-arguments
7749 \*(OB\*(BO Predecessor of
7750 .Va mta-no-default-arguments .
7753 .It Va sendmail-progname
7754 \*(OB Predecessor of
7759 \*(BO When sending a message wait until the
7761 (including the builtin SMTP one) exits before accepting further commands.
7763 with this variable set errors reported by the MTA will be recognizable!
7764 If the MTA returns a non-zero exit status,
7765 the exit status of \*(UA will also be non-zero.
7769 \*(BO Setting this option causes \*(UA to start at the last message
7770 instead of the first one when opening a mail folder.
7774 \*(BO Causes \*(UA to use the sender's real name instead of the plain
7775 address in the header field summary and in message specifications.
7779 \*(BO Causes the recipient of the message to be shown in the header
7780 summary if the message was sent by the user.
7784 A string for use with the
7790 A string for use with the
7796 Must correspond to the name of a readable file if set.
7797 The file's content is then appended to each singlepart message
7798 and to the first part of each multipart message.
7799 Be warned that there is no possibility to edit the signature for an
7803 .It Va skipemptybody
7804 \*(BO If an outgoing message does not contain any text in its first or
7805 only message part, do not send it but discard it silently (see also the
7811 \*(OP Specifies a directory with CA certificates in PEM (Privacy
7812 Enhanced Mail) format for verification of S/MIME signed messages.
7815 .It Va smime-ca-file
7816 \*(OP Specifies a file with CA certificates in PEM format for
7817 verification of S/MIME signed messages.
7820 .It Va smime-cipher-USER@HOST , smime-cipher
7821 \*(OP Specifies the cipher to use when generating S/MIME encrypted
7822 messages (for the specified account).
7823 RFC 5751 mandates a default of
7826 Possible values are (case-insensitive and) in decreasing cipher strength:
7834 (DES EDE3 CBC, 168 bits; default if
7836 isn't available) and
7840 The actually available cipher algorithms depend on the cryptographic
7841 library that \*(UA uses.
7842 \*(OP Support for more cipher algorithms may be available through
7843 dynamic loading via, e.g.,
7844 .Xr EVP_get_cipherbyname 3
7845 (OpenSSL) if \*(UA has been compiled to support this.
7848 .It Va smime-crl-dir
7849 \*(OP Specifies a directory that contains files with CRLs in PEM format
7850 to use when verifying S/MIME messages.
7853 .It Va smime-crl-file
7854 \*(OP Specifies a file that contains a CRL in PEM format to use when
7855 verifying S/MIME messages.
7858 .It Va smime-encrypt-USER@HOST
7859 \*(OP If this variable is set, messages send to the given receiver are
7860 encrypted before sending.
7861 The value of the variable must be set to the name of a file that
7862 contains a certificate in PEM format.
7864 If a message is sent to multiple recipients,
7865 each of them for whom a corresponding variable is set will receive an
7866 individually encrypted message;
7867 other recipients will continue to receive the message in plain text
7869 .Va smime-force-encryption
7871 It is recommended to sign encrypted messages, i.e., to also set the
7876 .It Va smime-force-encryption
7877 \*(BO\*(OP Causes \*(UA to refuse sending unencrypted messages.
7880 .It Va smime-no-default-ca
7881 \*(BO\*(OP Don't load default CA locations when verifying S/MIME signed
7886 \*(BO\*(OP S/MIME sign outgoing messages with the user's private key
7887 and include the user's certificate as a MIME attachment.
7888 Signing a message enables a recipient to verify that the sender used
7889 a valid certificate,
7890 that the email addresses in the certificate match those in the message
7891 header and that the message content has not been altered.
7892 It does not change the message text,
7893 and people will be able to read the message as usual.
7895 .Va smime-sign-cert , smime-sign-include-certs
7897 .Va smime-sign-message-digest .
7899 .Mx Va smime-sign-cert
7900 .It Va smime-sign-cert-USER@HOST , smime-sign-cert
7901 \*(OP Points to a file in PEM format.
7902 For the purpose of signing and decryption this file needs to contain the
7903 user's private key as well as his certificate.
7907 is always derived from the value of
7909 (or, if that contains multiple addresses,
7911 For the purpose of encryption the recipient's public encryption key
7912 (certificate) is expected; the command
7914 can be used to save certificates of signed messages (the section
7915 .Sx "Signed and encrypted messages with S/MIME"
7916 gives some details).
7917 This mode of operation is usually driven by the specialized form.
7919 When decrypting messages the account is derived from the recipient
7924 of the message, which are searched for addresses for which such
7926 \*(UA always uses the first address that matches,
7927 so if the same message is sent to more than one of the user's addresses
7928 using different encryption keys, decryption might fail.
7930 .Mx Va smime-sign-include-certs
7931 .It Va smime-sign-include-certs-USER@HOST , smime-sign-include-certs
7932 \*(OP If used, this is supposed to a consist of a comma-separated list
7933 of files, each of which containing a single certificate in PEM format to
7934 be included in the S/MIME message in addition to the
7937 This is most useful for long certificate chains if it is desired to aid
7938 the receiving party's verification process.
7939 Note that top level certificates may also be included in the chain but
7940 don't play a role for verification.
7942 .Va smime-sign-cert .
7943 Remember that for this
7945 refers to the variable
7947 (or, if that contains multiple addresses,
7950 .Mx Va smime-sign-message-digest
7951 .It Va smime-sign-message-digest-USER@HOST , smime-sign-message-digest
7952 \*(OP Specifies the message digest to use when signing S/MIME messages.
7953 RFC 5751 mandates a default of
7955 Possible values are (case-insensitive and) in decreasing cipher strength:
7963 The actually available message digest algorithms depend on the
7964 cryptographic library that \*(UA uses.
7965 \*(OP Support for more message digest algorithms may be available
7966 through dynamic loading via, e.g.,
7967 .Xr EVP_get_digestbyname 3
7968 (OpenSSL) if \*(UA has been compiled to support this.
7969 Remember that for this
7971 refers to the variable
7973 (or, if that contains multiple addresses,
7978 \*(OB\*(OP To use the builtin SMTP transport, specify a SMTP URL in
7980 \*(ID For compatibility reasons a set
7982 is used in preference of
7986 .It Va smtp-auth-USER@HOST , smtp-auth-HOST , smtp-auth
7987 \*(OP Variable chain that controls the SMTP
7989 authentication method, possible values are
7995 as well as the \*(OPal methods
8001 method doesn't need any user credentials,
8003 requires a user name and all other methods require a user name and
8011 .Va smtp-auth-password
8013 .Va smtp-auth-user ) .
8018 .Va smtp-auth-USER@HOST :
8019 may override dependent on sender address in the variable
8022 .It Va smtp-auth-password
8023 \*(OP\*(OU Sets the global fallback password for SMTP authentication.
8024 If the authentication method requires a password, but neither
8025 .Va smtp-auth-password
8027 .Va smtp-auth-password-USER@HOST
8029 \*(UA will ask for a password on the user's terminal.
8031 .It Va smtp-auth-password-USER@HOST
8033 .Va smtp-auth-password
8034 for specific values of sender addresses, dependent upon the variable
8037 .It Va smtp-auth-user
8038 \*(OP\*(OU Sets the global fallback user name for SMTP authentication.
8039 If the authentication method requires a user name, but neither
8042 .Va smtp-auth-user-USER@HOST
8044 \*(UA will ask for a user name on the user's terminal.
8046 .It Va smtp-auth-user-USER@HOST
8049 for specific values of sender addresses, dependent upon the variable
8053 .It Va smtp-hostname
8054 \*(OP\*(IN Normally \*(UA uses the variable
8056 to derive the necessary
8058 information in order to issue a
8065 can be used to use the
8067 from the SMTP account
8074 from the content of this variable (or, if that is the empty string,
8076 or the local hostname as a last resort).
8077 This often allows using an address that is itself valid but hosted by
8078 a provider other than which (in
8080 is about to send the message.
8081 Setting this variable also influences the generated
8084 .Mx Va smtp-use-starttls
8085 .It Va smtp-use-starttls-USER@HOST , smtp-use-starttls-HOST , smtp-use-starttls
8086 \*(BO\*(OP Causes \*(UA to issue a
8088 command to make an SMTP
8090 session SSL/TLS encrypted, i.e., to enable transport layer security.
8094 .It Va spam-interface
8095 \*(OP In order to use any of the spam-related commands (like, e.g.,
8097 the desired spam interface must be defined by setting this variable.
8098 Please refer to the manual section
8100 for the complete picture of spam handling in \*(UA.
8101 All or none of the following interfaces may be available:
8103 .Bl -tag -width ".It Ql _ilte_"
8109 .Pf ( Lk http://spamassassin.apache.org SpamAssassin )
8111 Different to the generic filter interface \*(UA will automatically add
8112 the correct arguments for a given command and has the necessary
8113 knowledge to parse the program's output.
8116 will have been compiled into the \*(UA binary if
8121 Shall it be necessary to define a specific connection type (rather than
8122 using a configuration file for that), the variable
8124 can be used as in, e.g.,
8125 .Ql -d server.example.com -p 783 .
8126 It is also possible to specify a per-user configuration via
8128 Note that this interface doesn't inspect the
8130 flag of a message for the command
8134 generic spam filter support via freely configurable hooks.
8135 This interface is meant for programs like
8137 and requires according behaviour in respect to the hooks' exit
8138 status for at least the command
8141 meaning a message is spam,
8145 for unsure and any other return value indicating a hard error);
8146 since the hooks can include shell code snippets diverting behaviour
8147 can be intercepted as necessary.
8149 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
8152 .Va spamfilter-spam ;
8155 contains examples for some programs.
8156 The process environment of the hooks will have the variables
8157 .Ev NAIL_TMPDIR , TMPDIR
8159 .Ev NAIL_FILENAME_GENERATED
8161 Note that spam score support for
8163 isn't supported unless the \*(OPtional regular expression support is
8165 .Va spamfilter-rate-scanscore
8172 \*(OP Messages that exceed this size won't be passed through to the
8174 .Va spam-interface .
8175 If unset or 0, the default of 420000 bytes is used.
8178 .It Va spamc-command
8179 \*(OP The path to the
8183 .Va spam-interface .
8184 Note that the path is not expanded, but used
8186 A fallback path will have been compiled into the \*(UA binary if the
8187 executable had been found during compilation.
8190 .It Va spamc-arguments
8191 \*(OP Even though \*(UA deals with most arguments for the
8194 automatically, it may at least sometimes be desirable to specify
8195 connection-related ones via this variable, e.g.,
8196 .Ql -d server.example.com -p 783 .
8200 \*(OP Specify a username for per-user configuration files for the
8202 .Va spam-interface .
8203 If this is set to the empty string then \*(UA will use the name of the
8212 .It Va spamfilter-ham , spamfilter-noham , \
8213 spamfilter-nospam , spamfilter-rate , spamfilter-spam
8214 \*(OP Command and argument hooks for the
8216 .Va spam-interface .
8219 contains examples for some programs.
8222 .It Va spamfilter-rate-scanscore
8223 \*(OP Because of the generic nature of the
8226 spam scores are not supported for it by default, but if the \*(OPtional
8227 regular expression support is available then setting this variable can
8228 be used to overcome this restriction.
8229 It is interpreted as follows: first a number (digits) is parsed that
8230 must be followed by a semicolon
8232 and an extended regular expression.
8233 Then the latter is used to parse the first output line of the
8235 hook, and, in case the evaluation is successful, the group that has been
8236 specified via the number is interpreted as a floating point scan score.
8240 \*(OP Specifies a directory with CA certificates in PEM (Pricacy
8241 Enhanced Mail) for verification of of SSL/TLS server certificates.
8243 .Xr SSL_CTX_load_verify_locations 3
8244 for more information.
8248 \*(OP Specifies a file with CA certificates in PEM format for
8249 verification of SSL/TLS server certificates.
8251 .Xr SSL_CTX_load_verify_locations 3
8252 for more information.
8255 .It Va ssl-cert-USER@HOST , ssl-cert-HOST , ssl-cert
8256 \*(OP Variable chain that sets the file name for a SSL/TLS client
8257 certificate required by some servers.
8258 This is a direct interface to the
8262 function of the OpenSSL library, if available.
8264 .Mx Va ssl-cipher-list
8265 .It Va ssl-cipher-list-USER@HOST , ssl-cipher-list-HOST , ssl-cipher-list
8266 \*(OP Specifies a list of ciphers for SSL/TLS connections.
8267 This is a direct interface to the
8271 function of the OpenSSL library, if available; see
8273 for more information.
8274 By default \*(UA doesn't set a list of ciphers, which in effect will use a
8276 specific cipher (protocol standards ship with a list of acceptable
8277 ciphers), possibly cramped to what the actually used SSL/TLS library
8278 supports \(en the manual section
8279 .Sx "An example configuration"
8280 also contains a SSL/TLS use case.
8283 .It Va ssl-config-file
8284 \*(OP If this variable is set \*(UA will call
8285 .Xr CONF_modules_load_file 3
8286 to allow OpenSSL to be configured according to the host system wide
8288 If a non-empty value is given then this will be used to specify the
8289 configuration file to be used instead of the global OpenSSL default;
8290 note that in this case it is an error if the file cannot be loaded.
8291 The application name will always be passed as
8296 \*(OP Specifies a file that contains a CRL in PEM format to use when
8297 verifying SSL/TLS server certificates.
8301 \*(OP Specifies a directory that contains files with CRLs in PEM format
8302 to use when verifying SSL/TLS server certificates.
8305 .It Va ssl-key-USER@HOST , ssl-key-HOST , ssl-key
8306 \*(OP Variable chain that sets the file name for the private key of
8307 a SSL/TLS client certificate.
8308 If unset, the name of the certificate file is used.
8309 The file is expected to be in PEM format.
8310 This is a direct interface to the
8314 function of the OpenSSL library, if available.
8317 .It Va ssl-method-USER@HOST , ssl-method-HOST , ssl-method
8318 \*(OB\*(OP Please use the newer and more flexible
8320 instead: if both values are set,
8322 will take precedence!
8323 Can be set to the following values, the actually used
8325 specification to which it is mapped is shown in parenthesis:
8327 .Pf ( Ql -ALL, TLSv1.2 ) ,
8329 .Pf ( Ql -ALL, TLSv1.1 ) ,
8331 .Pf ( Ql -ALL, TLSv1 )
8334 .Pf ( Ql -ALL, SSLv3 ) ;
8339 and thus includes the SSLv3 protocol.
8340 Note that SSLv2 is no longer supported at all.
8343 .It Va ssl-no-default-ca
8344 \*(BO\*(OP Don't load default CA locations to verify SSL/TLS server
8348 .It Va ssl-protocol-USER@HOST , ssl-protocol-HOST , ssl-protocol
8349 \*(OP Specify the used SSL/TLS protocol.
8350 This is a direct interface to the
8354 function of the OpenSSL library, if available;
8355 otherwise an \*(UA internal parser is used which understands the
8356 following subset of (case-insensitive) command strings:
8362 as well as the special value
8364 Multiple specifications may be given via a comma-separated list which
8365 ignores any whitespace.
8368 plus prefix will enable a protocol, a
8370 minus prefix will disable it, so that
8372 will enable only the TLSv1.2 protocol.
8374 It depends upon the used TLS/SSL library which protocols are actually
8375 supported and which protocols are used if
8377 is not set, but note that SSLv2 is no longer supported at all and
8379 Especially for older protocols explicitly securing
8381 may be worthwile, see
8382 .Sx "An example configuration" .
8386 \*(OP Gives the pathname to an entropy daemon socket, see
8388 Not all SSL/TLS libraries support this.
8391 .It Va ssl-rand-file
8392 \*(OP Gives the filename to a file with random entropy data, see
8393 .Xr RAND_load_file 3 .
8394 If this variable is not set, or set to the empty string, or if the
8395 filename expansion failed, then
8396 .Xr RAND_file_name 3
8397 will be used to create the filename if, and only if,
8399 documents that the SSL PRNG is not yet sufficiently seeded.
8400 If \*(UA successfully seeded the SSL PRNG then it'll update the file via
8401 .Xr RAND_write_file 3 .
8402 This variable is only used if
8404 is not set (or not supported by the SSL/TLS library).
8407 .It Va ssl-verify-USER@HOST , ssl-verify-HOST , ssl-verify
8408 \*(OP Variable chain that sets the action to be performed if an error
8409 occurs during SSL/TLS server certificate validation.
8410 Valid (case-insensitive) values are
8412 (fail and close connection immediately),
8414 (ask whether to continue on standard input),
8416 (show a warning and continue),
8418 (do not perform validation).
8424 If only set without an assigned value, then this option inhibits the
8429 header fields that include obvious references to \*(UA.
8430 There are two pitfalls associated with this:
8431 First, the message id of outgoing messages is not known anymore.
8432 Second, an expert may still use the remaining information in the header
8433 to track down the originating mail user agent.
8438 suppression doesn't occur.
8443 (\*(OP) This specifies a comma-separated list of
8448 .Sx "On terminal control and line editor" ,
8449 escape commas with reverse solidus) to be used to overwrite or define
8451 Note that this variable will only be queried once at program startup and
8452 can thus only be specified in resource files or on the command line.
8455 String capabilities form
8457 pairs and are expected unless noted otherwise.
8458 Numerics have to be notated as
8460 where the number is expected in normal decimal notation.
8461 Finally, booleans don't have any value but indicate a true or false
8462 state simply by being defined or not; this indeed means that \*(UA
8463 doesn't support undefining an existing boolean.
8464 String capability values will undergo some expansions before use:
8465 for one notations like
8468 .Ql control-LETTER ,
8469 and for clarification purposes
8471 can be used to specify
8473 (the control notation
8475 could lead to misreadings when a left bracket follows, which it does for
8476 the standard CSI sequence);
8477 finally three letter octal sequences, as in
8480 To specify that a terminal supports 256-colours, and to define sequences
8481 that home the cursor and produce an audible bell, one might write:
8483 .Bd -literal -offset indent
8484 set termcap='Co#256,home=\eE[H,bel=^G'
8488 The following terminal capabilities are or may be meaningful for the
8489 operation of the builtin line editor or \*(UA in general:
8492 .Bl -tag -compact -width yay
8494 .It Cd colors Ns \0or Cd Co
8496 numeric capability specifying the maximum number of colours.
8497 Note that \*(UA doesn't actually care about the terminal beside that,
8498 but always emits ANSI / ISO 6429 escape sequences.
8501 .It Cd rmcup Ns \0or Cd te Ns \0/ Cd smcup Ns \0or Cd ti
8505 respectively: exit and enter the alternative screen
8507 effectively turning \*(UA into a fullscreen application.
8508 To disable that, set (at least) one to the empty string.
8510 .It Cd smkx Ns \0or Cd ks Ns \0/ Cd rmkx Ns \0or Cd ke
8514 respectively: enable and disable the keypad.
8515 This is always enabled if available, because it seems even keyboards
8516 without keypads generate other key codes for, e.g., cursor keys in that
8517 case, and only if enabled we see the codes that we are interested in.
8519 .It Cd ed Ns \0or Cd cd
8523 .It Cd clear Ns \0or Cd cl
8525 clear the screen and home cursor.
8526 (Will be simulated via
8531 .It Cd home Ns \0or Cd ho
8536 .It Cd el Ns \0or Cd ce
8538 clear to the end of line.
8539 (Will be simulated via
8541 plus repetitions of space characters.)
8543 .It Cd hpa Ns \0or Cd ch
8544 .Cd column_address :
8545 move the cursor (to the given column parameter) in the current row.
8546 (Will be simulated via
8552 .Cd carriage_return :
8553 move to the first column in the current row.
8554 The default builtin fallback is
8557 .It Cd cub1 Ns \0or Cd le
8559 move the cursor left one space (non-destructively).
8560 The default builtin fallback is
8563 .It Cd cuf1 Ns \0or Cd nd
8565 move the cursor right one space (non-destructively).
8566 The default builtin fallback is
8568 which is used by most terminals.
8576 Many more capabilities which describe key-sequences are documented for
8580 .It Va termcap-disable
8581 \*(OP Disable any interaction with a terminal control library.
8582 If set only some generic fallback builtins and possibly the content of
8584 describe the terminal to \*(UA.
8586 that this variable will only be queried once at program startup and can
8587 thus only be specified in resource files or on the command line.
8591 If defined, gives the number of lines of a message to be displayed
8594 if unset, the first five lines are printed, if set to 0 the variable
8597 If the value is negative then its absolute value will be used for right
8600 height; (shifting bitwise is like dividing algorithmically, but since
8601 it takes away bits the value decreases pretty fast).
8605 \*(BO If set then the
8607 command series will strip adjacent empty lines and quotations.
8611 The character set of the terminal \*(UA operates on,
8612 and the one and only supported character set that \*(UA can use if no
8613 character set conversion capabilities have been compiled into it,
8614 in which case it defaults to ISO-8859-1 unless it can deduce a value
8618 Refer to the section
8619 .Sx "Character sets"
8620 for the complete picture about character sets.
8624 For a safety-by-default policy \*(UA sets its process
8628 but this variable can be used to override that:
8629 set it to an empty value to don't change the (current) setting,
8630 otherwise the process file mode creation mask is updated to the new value.
8631 Child processes inherit the process file mode creation mask.
8634 .It Va user-HOST , user
8635 \*(IN Variable chain that sets a global fallback user name, which is
8636 used in case none has been given in the protocol and account-specific
8638 This variable defaults to the name of the user who runs \*(UA.
8642 \*(BO Setting this option enables upward compatibility with \*(UA
8643 version 15.0 in respect to which configuration options are available and
8644 how they are handled.
8645 This manual uses \*(IN and \*(OU to refer to the new and the old way of
8646 doing things, respectively.
8650 \*(BO Setting this option, also controllable via the command line option
8652 causes \*(UA to be more verbose, e.g., it will display obsoletion
8653 warnings and SSL/TLS certificate chains.
8654 Even though marked \*(BO this option may be set twice in order to
8655 increase the level of verbosity even more, in which case even details of
8656 the actual message delivery and protocol conversations are shown.
8659 is sufficient to disable verbosity as such.
8665 .It Va version , version-major , version-minor , version-update
8666 \*(RO \*(UA version information: the first variable contains a string
8667 containing the complete version identification \(en this is identical to
8668 the output of the command
8670 The latter three contain only digits: the major, minor and update
8674 .It Va writebackedited
8675 If this variable is set messages modified using the
8679 commands are written back to the current folder when it is quit;
8680 it is only honoured for writable folders in MBOX format, though.
8681 Note that the editor will be pointed to the raw message content in that
8682 case, i.e., neither MIME decoding nor decryption will have been
8683 performed, and proper RFC 4155
8685 quoting of newly added or edited content is also left as an excercise to
8689 .\" }}} (INTERNAL VARIABLES)
8692 .\" .Sh ENVIRONMENT {{{
8696 .Dq environment variable
8697 should be considered an indication that these variables are either
8698 standardized as vivid parts of process environments, or that they are
8699 commonly found in there.
8700 The process environment is inherited from the
8702 once \*(UA is started, and unless otherwise explicitly noted handling of
8703 the following variables transparently integrates into that of the
8704 .Sx "INTERNAL VARIABLES"
8705 from \*(UA's point of view.
8706 This means that, e.g., they can be managed via
8710 causing automatic program environment updates (to be inherited by
8711 newly created child processes).
8714 In order to transparently integrate other environment variables equally
8715 they need to be imported (linked) with the command
8717 This command can also be used to set and unset non-integrated
8718 environment variables from scratch, sufficient system support provided.
8719 The following example, applicable to a POSIX shell, sets the
8721 environment variable for \*(UA only, and beforehand exports the
8723 in order to affect any further processing in the running shell:
8725 .Bd -literal -offset indent
8726 $ EDITOR="vim -u ${HOME}/.vimrc"
8728 $ COLUMNS=80 \*(uA -R
8731 .Bl -tag -width ".It Ev _AILR_"
8734 The user's preferred width in column positions for the terminal screen
8736 Queried and used once on program startup, actively managed for child
8737 processes and the MLE (see
8738 .Sx "On terminal control and line editor" )
8739 in interactive mode thereafter.
8743 The name of the (mailbox)
8745 to use for saving aborted messages if
8747 is set; this defaults to
8754 is set no output will be generated, otherwise the contents of the file
8759 Pathname of the text editor to use in the
8763 .Sx "TILDE ESCAPES" .
8764 A default editor is used if this value is not defined.
8768 The user's home directory.
8769 This variable is only used when it resides in the process environment.
8776 .It Ev LANG , LC_ALL , LC_COLLATE , LC_CTYPE , LC_MESSAGES
8780 .Sx "Character sets" .
8781 (Only recognized by the system in the process environment.)
8785 The user's preferred number of lines on a page or the vertical screen
8786 or window size in lines.
8787 Queried and used once on program startup, actively managed for child
8788 processes in interactive mode thereafter.
8792 Pathname of the directory lister to use in the
8794 command when operating on local mailboxes.
8797 (path search through
8802 Upon startup \*(UA will actively ensure that this variable refers to the
8803 name of the user who runs \*(UA, in order to be able to pass a verified
8804 name to any newly created child process.
8808 Is used as the user's primary system mailbox, if set.
8809 Otherwise, a system-dependent default is used.
8810 Supports the special syntax conventions that are documented for the
8816 \*(OP Overrides the default path search for
8817 .Sx "The Mailcap files" ,
8818 which is defined in the standard RFC 1524 as
8819 .Ql ~/.mailcap:\:/etc/mailcap:\:/usr/etc/mailcap:\:/usr/local/etc/mailcap .
8820 .\" TODO we should have a mailcaps-default virtual RDONLY option!
8821 (\*(UA makes it a configuration option, however.)
8822 Note this is not a search path, but a path search.
8826 Is used as a startup file instead of
8829 When \*(UA scripts are invoked on behalf of other users,
8830 either this variable should be set to
8834 command line option should be used in order to avoid side-effects from
8835 reading their configuration files.
8836 This variable is only used when it resides in the process environment.
8840 The name of the user's mbox file.
8841 A logical subset of the special conventions that are documented for the
8846 The fallback default is
8851 Traditionally this secondary mailbox is used as the file to save
8852 messages from the primary system mailbox that have been read.
8854 .Sx "Message states" .
8857 .It Ev NAIL_NO_SYSTEM_RC
8858 If this variable is set then reading of
8860 at startup is inhibited, i.e., the same effect is achieved as if \*(UA
8861 had been started up with the option
8863 This variable is only used when it resides in the process environment.
8867 \*(IN\*(OP This variable overrides the default location of the user's
8873 Pathname of the program to use for backing the command
8877 variable enforces usage of a pager for output.
8878 The default paginator is
8880 (path search through
8883 \*(UA inspects the contents of this variable: if its contains the string
8885 then a non-existing environment variable
8892 dependent on whether terminal control support is available and whether
8893 that supports full (alternative) screen mode or not (also see
8894 .Sx "On terminal control and line editor" ) .
8898 will optionally be set to
8905 A list of directories that is searched by the shell when looking for
8906 commands (as such only recognized in the process environment).
8910 The shell to use for the commands
8916 and when starting subprocesses.
8917 A default shell is used if this option is not defined.
8920 .It Ev SOURCE_DATE_EPOCH
8921 If set, this specifies a time in seconds since the Unix epoch
8922 (1970-01-01) to be used in place of the current time.
8923 This is for the sake of reproduceability of tests, to be used during
8924 development or by software packagers.
8928 \*(OP The terminal type for which output is to be prepared.
8929 For extended colour and font control please refer to
8930 .Sx "Coloured display" ,
8931 and for terminal management in general to
8932 .Sx "On terminal control and line editor" .
8936 Used as directory for temporary files instead of
8939 This variable is only used when it resides in the process environment.
8945 (see there), but this variable is not standardized, should therefore not
8946 be used, and is only corrected if already set.
8950 Pathname of the text editor to use in the
8954 .Sx "TILDE ESCAPES" .
8962 .Bl -tag -width ".It Pa _etc/mime.type_"
8964 File giving initial commands.
8967 System wide initialization file.
8971 \*(OP Personal MIME type handler definition file, see
8972 .Sx "The Mailcap files" .
8973 (RFC 1524 location, the actual path is a configuration option.)
8977 \*(OP System wide MIME type handler definition file, see
8978 .Sx "The Mailcap files" .
8979 (RFC 1524 location, the actual path is a configuration option.)
8982 .It Pa ~/.mime.types
8983 Personal MIME types, see
8984 .Sx "The mime.types files" .
8987 .It Pa /etc/mime.types
8988 System wide MIME types, see
8989 .Sx "The mime.types files" .
8993 \*(IN\*(OP The default location of the users
8995 file \(en the section
8996 .Sx "The .netrc file"
8997 documents the file format.
9000 .\" .Ss "The mime.types files" {{{
9001 .Ss "The mime.types files"
9003 When sending messages \*(UA tries to determine the content type of all
9005 When displaying message content or attachments \*(UA uses the content
9006 type to decide whether it can directly display data or whether it needs
9007 to deal with content handlers.
9008 It learns about MIME types and how to treat them by reading
9010 files, the loading of which can be controlled by setting the variable
9011 .Va mimetypes-load-control .
9014 can also be used to deal with MIME types.)
9016 files have the following syntax:
9019 .Dl type/subtype extension [extension ...]
9024 are strings describing the file contents, and one or multiple
9026 s, separated by whitespace, name the part of a filename starting after
9027 the last dot (of interest).
9028 Comments may be introduced anywhere on a line with a number sign
9030 causing the remaining line to be discarded.
9032 \*(UA also supports an extended, non-portable syntax in specially
9033 crafted files, which can be loaded via the alternative value syntax of
9034 .Va mimetypes-load-control
9035 and prepends an optional
9039 .Dl [type-marker ]type/subtype extension [extension ...]
9042 The following type markers are supported:
9045 .Bl -tag -compact -offset indent -width ".It Ar _n_u"
9047 Treat message parts with this content as plain text.
9052 Treat message parts with this content as HTML tagsoup.
9053 If the \*(OPal HTML-tagsoup-to-text converter is not available treat
9054 the content as plain text instead.
9058 but instead of falling back to plain text require an explicit content
9059 handler to be defined.
9064 for sending messages:
9066 .Va mime-allow-text-controls ,
9067 .Va mimetypes-load-control .
9068 For reading etc. messages:
9069 .Sx "HTML mail and MIME attachments" ,
9070 .Sx "The Mailcap files" ,
9072 .Va mime-counter-evidence ,
9073 .Va mimetypes-load-control ,
9074 .Va pipe-TYPE/SUBTYPE ,
9075 .Va pipe-EXTENSION .
9078 .\" .Ss "The Mailcap files" {{{
9079 .Ss "The Mailcap files"
9082 .Dq User Agent Configuration Mechanism
9083 which \*(UA \*(OPally supports.
9084 It defines a file format to be used to inform mail user agent programs
9085 about the locally-installed facilities for handling various data
9086 formats, i.e., about commands and how they can be used to display, edit
9087 etc. MIME part contents, as well as a default path search that includes
9088 multiple possible locations of
9092 environment variable that can be used to overwrite that (repeating here
9093 that it is not a search path, but instead a path search specification).
9094 Any existing files will be loaded in sequence, appending any content to
9095 the list of MIME type handler directives.
9099 files consist of a set of newline separated entries.
9100 Comment lines start with a number sign
9102 (in the first column!) and are ignored.
9103 Empty lines are also ignored.
9104 All other lines form individual entries that must adhere to the syntax
9106 To extend a single entry (not comment) its line can be continued on
9107 follow lines if newline characters are
9109 by preceding them with the reverse solidus character
9111 The standard doesn't specify how leading whitespace of follow lines is
9112 to be treated, therefore \*(UA retains it.
9116 entries consist of a number of semicolon
9118 separated fields, and the reverse solidus
9120 character can be used to escape any following character including
9121 semicolon and itself.
9122 The first two fields are mandatory and must occur in the specified
9123 order, the remaining fields are optional and may appear in any order.
9124 Leading and trailing whitespace of content is ignored (removed).
9127 The first field defines the MIME
9129 the entry is about to handle (case-insensitively, and no reverse solidus
9130 escaping is possible in this field).
9131 If the subtype is specified as an asterisk
9133 the entry is meant to match all subtypes of the named type, e.g.,
9135 would match any audio type.
9136 The second field defines the shell command which shall be used to
9138 MIME parts of the given type; it is implicitly called the
9145 shell commands message (MIME part) data is passed via standard input
9146 unless the given shell command includes one or more instances of the
9149 in which case these instances will be replaced with a temporary filename
9150 and the data will have been stored in the file that is being pointed to.
9153 shell commands data is assumed to be generated on standard output unless
9154 the given command includes (one ore multiple)
9156 In any case any given
9158 format is replaced with a(n already) properly quoted filename.
9159 Note that when a command makes use of a temporary file via
9161 then \*(UA will remove it again, as if the
9162 .Cd x-mailx-tmpfile ,
9163 .Cd x-mailx-tmpfile-fill
9165 .Cd x-mailx-tmpfile-unlink
9166 flags had been set; see below for more.
9169 The optional fields either define a shell command or an attribute (flag)
9170 value, the latter being a single word and the former being a keyword
9171 naming the field followed by an equals sign
9173 succeeded by a shell command, and as usual for any
9175 content any whitespace surrounding the equals sign will be removed, too.
9176 Optional fields include the following:
9179 .Bl -tag -width textualnewlines
9181 A program that can be used to compose a new body or body part in the
9188 field, but is to be used when the composing program needs to specify the
9190 header field to be applied to the composed data.
9194 A program that can be used to edit a body or body part in the given
9199 A program that can be used to print a message or body part in the given
9204 Specifies a program to be run to test some condition, e.g., the machine
9205 architecture, or the window system in use, to determine whether or not
9206 this mailcap entry applies.
9207 If the test fails, a subsequent mailcap entry should be sought; also see
9208 .Cd x-mailx-test-once .
9210 .It Cd needsterminal
9211 This flag field indicates that the given shell command must be run on
9212 an interactive terminal.
9213 \*(UA will temporarily release the terminal to the given command in
9214 interactive mode, in non-interactive mode this entry will be entirely
9215 ignored; this flag implies
9216 .Cd x-mailx-noquote .
9218 .It Cd copiousoutput
9219 A flag field which indicates that the output of the
9221 command will be an extended stream of textual output that can be
9222 (re)integrated into \*(UA's normal visual display.
9223 It is mutually exclusive with
9226 .Cd x-mailx-always .
9228 .It Cd textualnewlines
9229 A flag field which indicates that this type of data is line-oriented and
9232 all newlines should be converted to canonical form (CRLF) before
9233 encoding, and will be in that form after decoding.
9237 This field gives a file name format, in which
9239 will be replaced by a random string, the joined combination of which
9240 will be used as the filename denoted by
9241 .Ev NAIL_FILENAME_TEMPORARY .
9242 One could specify that a GIF file being passed to an image viewer should
9243 have a name ending in
9246 .Ql nametemplate=%s.gif .
9247 Note that \*(UA ignores the name template unless that solely specifies
9248 a filename suffix that consists of (ASCII) alphabetic and numeric
9249 characters, the underscore and dot only.
9252 Names a file, in X11 bitmap (xbm) format, which points to an appropriate
9253 icon to be used to visually denote the presence of this kind of data.
9254 This field is not used by \*(UA.
9257 A textual description that describes this type of data.
9259 .It Cd x-mailx-always
9260 Extension flag field that denotes that the given
9262 command shall be executed even if multiple messages will be displayed
9264 Normally messages which require external viewers that produce output
9265 which doesn't integrate into \*(UA's visual display (i.e., don't have
9267 set) have to be addressed directly and individually.
9268 (To avoid cases where, e.g., a thousand PDF viewer instances are spawned
9271 .It Cd x-mailx-even-if-not-interactive
9272 An extension flag test field \(em by default handlers without
9274 are entirely ignored in non-interactive mode, but if this flag is set
9275 then their use will be considered.
9276 It is an error if this flag is set for commands that use the flag
9279 .It Cd x-mailx-noquote
9280 An extension flag field that indicates that even a
9283 command shall not be used to generate message quotes
9284 (as it would be by default).
9286 .It Cd x-mailx-async
9287 Extension flag field that denotes that the given
9289 command shall be executed asynchronously, without blocking \*(UA.
9290 Cannot be used in conjunction with
9293 .It Cd x-mailx-test-once
9294 Extension flag which denotes whether the given
9296 command shall be evaluated once only and the (boolean) result be cached.
9297 This is handy if some global unchanging condition is to be queried, like
9298 .Dq running under the X Window System .
9300 .It Cd x-mailx-tmpfile
9301 Extension flag field that requests creation of a zero-sized temporary
9302 file, the name of which is to be placed in the environment variable
9303 .Ev NAIL_FILENAME_TEMPORARY .
9304 It is an error to use this flag with commands that include a
9308 .It Cd x-mailx-tmpfile-fill
9309 Normally the MIME part content is passed to the handler via standard
9310 input; if this flag is set then the data will instead be written into
9312 .Cd x-mailx-tmpfile .
9313 In order to cause deletion of the temporary file you will have to set
9314 .Cd x-mailx-tmpfile-unlink
9316 It is an error to use this flag with commands that include a
9320 .It Cd x-mailx-tmpfile-unlink
9321 Extension flag field that requests that the temporary file shall be
9322 deleted automatically when the command loop is entered again at latest.
9323 (Don't use this for asynchronous handlers.)
9324 It is an error to use this flag with commands that include a
9326 format, or without also setting
9329 .Cd x-mailx-tmpfile-fill .
9331 .It Cd x-mailx-tmpfile-keep
9334 implies the three tmpfile related flags above, but if you want, e.g.,
9336 and deal with the temporary file yourself, you can add in this flag to
9338 .Cd x-mailx-tmpfile-unlink .
9343 The standard includes the possibility to define any number of additional
9344 entry fields, prefixed by
9346 Flag fields apply to the entire
9348 entry \(em in some unusual cases, this may not be desirable, but
9349 differentiation can be accomplished via separate entries, taking
9350 advantage of the fact that subsequent entries are searched if an earlier
9351 one does not provide enough information.
9354 command needs to specify the
9358 command shall not, the following will help out the latter (with enabled
9362 level \*(UA will show information about handler evaluation):
9364 .Bd -literal -offset indent
9365 application/postscript; ps-to-terminal %s; needsterminal
9366 application/postscript; ps-to-terminal %s; compose=idraw %s
9370 In fields any occurrence of the format string
9372 will be replaced by the
9375 Named parameters from the
9377 field may be placed in the command execution line using
9379 followed by the parameter name and a closing
9382 The entire parameter should appear as a single command line argument,
9383 regardless of embedded spaces; thus:
9385 .Bd -literal -offset indent
9387 Content-type: multipart/mixed; boundary=42
9390 multipart/*; /usr/local/bin/showmulti \e
9391 %t %{boundary} ; composetyped = /usr/local/bin/makemulti
9393 # Executed shell command
9394 /usr/local/bin/showmulti multipart/mixed 42
9398 .\" TODO v15: Mailcap: %n,%F
9399 Note that \*(UA doesn't support handlers for multipart MIME parts as
9400 shown in this example (as of today).
9401 \*(UA doesn't support the additional formats
9405 An example file, also showing how to properly deal with the expansion of
9407 which includes any quotes that are necessary to make it a valid shell
9408 argument by itself and thus will cause undesired behaviour when placed
9409 in additional user-provided quotes:
9411 .Bd -literal -offset indent
9413 text/richtext; richtext %s; copiousoutput
9415 text/x-perl; perl -cWT %s
9419 trap "rm -f ${infile}" EXIT\e; \e
9420 trap "exit 75" INT QUIT TERM\e; \e
9422 x-mailx-async; x-mailx-tmpfile-keep
9424 application/*; echo "This is \e"%t\e" but \e
9425 is 50 \e% Greek to me" \e; < %s head -c 1024 | cat -vET; \e
9426 copiousoutput; x-mailx-noquote
9431 .Sx "HTML mail and MIME attachments" ,
9432 .Sx "The mime.types files" ,
9435 .Va mime-counter-evidence ,
9436 .Va pipe-TYPE/SUBTYPE ,
9437 .Va pipe-EXTENSION .
9440 .\" .Ss "The .netrc file" {{{
9441 .Ss "The .netrc file"
9445 file contains user credentials for machine accounts.
9446 The default location in the user's
9448 directory may be overridden by the
9450 environment variable.
9451 The file consists of space, tabulator or newline separated tokens.
9452 \*(UA implements a parser that supports a superset of the original BSD
9453 syntax, but users should nonetheless be aware of portability glitches
9454 of that file format, shall their
9456 be usable across multiple programs and platforms:
9459 .Bl -bullet -compact
9461 BSD doesn't support single, but only double quotation marks, e.g.,
9462 .Ql password="pass with spaces" .
9464 BSD (only?) supports escaping of single characters via a reverse solidus
9465 (e.g., a space can be escaped via
9467 in- as well as outside of a quoted string.
9469 BSD doesn't require the final quotation mark of the final user input token.
9471 The original BSD (Berknet) parser also supported a format which allowed
9472 tokens to be separated with commas \(en whereas at least Hewlett-Packard
9473 still seems to support this syntax, \*(UA does not!
9475 As a non-portable extension some widely-used programs support
9476 shell-style comments: if an input line starts, after any amount of
9477 whitespace, with a number sign
9479 then the rest of the line is ignored.
9481 Whereas other programs may require that the
9483 file is accessible by only the user if it contains a
9489 \*(UA will always require these strict permissions.
9493 Of the following list of supported tokens \*(UA only uses (and caches)
9498 At runtime the command
9500 can be used to control \*(UA's
9504 .Bl -tag -width password
9505 .It Cd machine Ar name
9506 The hostname of the entries' machine, lowercase-normalized by \*(UA
9508 Any further file content, until either end-of-file or the occurrence
9513 first-class token is bound (only related) to the machine
9516 As an extension that shouldn't be the cause of any worries
9517 \*(UA supports a single wildcard prefix for
9519 .Bd -literal -offset indent
9520 machine *.example.com login USER password PASS
9521 machine pop3.example.com login USER password PASS
9522 machine smtp.example.com login USER password PASS
9528 .Ql pop3.example.com ,
9532 .Ql local.smtp.example.com .
9533 Note that in the example neither
9534 .Ql pop3.example.com
9536 .Ql smtp.example.com
9537 will be matched by the wildcard, since the exact matches take
9538 precedence (it is however faster to specify it the other way around).
9543 except that it is a fallback entry that is used shall none of the
9544 specified machines match; only one default token may be specified,
9545 and it must be the last first-class token.
9547 .It Cd login Ar name
9548 The user name on the remote machine.
9550 .It Cd password Ar string
9551 The user's password on the remote machine.
9553 .It Cd account Ar string
9554 Supply an additional account password.
9555 This is merely for FTP purposes.
9557 .It Cd macdef Ar name
9559 A macro is defined with the specified
9561 it is formed from all lines beginning with the next line and continuing
9562 until a blank line is (consecutive newline characters are) encountered.
9565 entries cannot be utilized by multiple machines, too, but must be
9566 defined following the
9568 they are intended to be used with.)
9571 exists, it is automatically run as the last step of the login process.
9572 This is merely for FTP purposes.
9579 .\" .Sh EXAMPLES {{{
9582 .\" .Ss "An example configuration" {{{
9583 .Ss "An example configuration"
9585 .Bd -literal -offset indent
9586 # This example assumes v15.0 compatibility mode
9589 # Where are the up-to-date SSL certificates?
9590 #set ssl-ca-dir=/etc/ssl/certs
9591 set ssl-ca-file=/etc/ssl/certs/ca-certificates.crt
9593 # (Since we manage up-to-date ones explicitly, don't use any,
9594 # possibly outdated, default certificates shipped with OpenSSL)
9595 set ssl-no-default-ca
9597 # Don't use protocols older than TLS v1.2.
9598 # Change this only when the remote server doesn't support it:
9599 # maybe use ssl-protocol-HOST (or -USER@HOST) syntax to define
9600 # such explicit exceptions, then
9601 set ssl-protocol='-ALL,+TLSv1.2'
9603 # Explicitly define the list of ciphers, which may improve security,
9604 # especially with protocols older than TLS v1.2. See ciphers(1).
9605 # Including "@STRENGTH" will sort the final list by algorithm strength.
9606 # In reality it is possibly best to only use ssl-cipher-list-HOST
9607 # (or -USER@HOST), as necessary, again..
9608 set ssl-cipher-list=TLSv1.2:!aNULL:!eNULL:!MEDIUM:!LOW:!EXPORT:@STRENGTH
9609 # ALL:!aNULL:!MEDIUM:!LOW:!MD5:!RC4:!EXPORT:@STRENGTH
9611 # Request strict transport security checks!
9612 set ssl-verify=strict
9614 # Essential setting: select allowed character sets
9615 set sendcharsets=utf-8,iso-8859-1
9617 # A very kind option: when replying to a message, first try to
9618 # use the same encoding that the original poster used herself!
9619 set reply-in-same-charset
9621 # When replying to or forwarding a message the comment and name
9622 # parts of email addresses are removed unless this variable is set
9625 # When sending messages, wait until the Mail-Transfer-Agent finishs.
9626 # Only like this you'll be able to see errors reported through the
9627 # exit status of the MTA (including the builtin SMTP one)!
9630 # Only use builtin MIME types, no mime.types(5) files
9631 set mimetypes-load-control
9633 # Default directory where we act in (relative to $HOME)
9635 # A leading "+" (often) means: under *folder*
9636 # *record* is used to save copies of sent messages
9637 set MBOX=+mbox.mbox record=+sent.mbox DEAD=+dead.txt
9639 # Make "file mymbox" and "file myrec" go to..
9640 shortcut mymbox %:+mbox.mbox myrec +sent.mbox
9642 # Not really optional, e.g., for S/MIME
9643 set from='Your Name <address@exam.ple>'
9645 # It may be necessary to set hostname and/or smtp-hostname
9646 # if the "SERVER" of mta and "domain" of from don't match.
9647 # The `urlencode' command can be used to encode USER and PASS
9648 set mta=(smtps?|submission)://[USER[:PASS]@]SERVER[:PORT] \e
9649 smtp-auth=login/plain... \e
9652 # Never refuse to start into interactive mode, and more
9654 colour-pager crt= \e
9655 followup-to followup-to-honour=ask-yes \e
9656 history-file=+.\*(uAhist history-size=-1 history-gabby \e
9657 mime-counter-evidence=0xE \e
9658 prompt='?\e?[\e$ \e@]\e& ' \e
9659 reply-to-honour=ask-yes \e
9662 # When `t'yping messages, show only these headers
9663 # (use `T'ype for all headers and `S'how for raw message)
9664 retain date from to cc subject
9666 # Some mailing lists
9667 mlist '@xyz-editor\e.xyz$' '@xyzf\e.xyz$'
9668 mlsubscribe '^xfans@xfans\e.xyz$'
9670 # A real life example of a very huge free mail provider
9672 set folder=~/spool/XooglX MAIL=+syste.mbox sent=+sent
9673 set from='Your Name <address@examp.ple>'
9674 set mta=smtp://USER:PASS@smtp.gmXil.com smtp-use-starttls
9677 # Here is a pretty large one which does not allow sending mails
9678 # if there is a domain name mismatch on the SMTP protocol level,
9679 # which would bite us if the value of from does not match, e.g.,
9680 # for people who have a sXXXXeforge project and want to speak
9681 # with the mailing list under their project account (in from),
9682 # still sending the message through their normal mail provider
9684 set folder=~/spool/XandeX MAIL=+syste.mbox sent=+sent
9685 set from='Your Name <address@exam.ple>'
9686 set mta=smtps://USER:PASS@smtp.yaXXex.ru:465 \e
9687 hostname=yaXXex.com smtp-hostname=
9690 # Create some new commands so that, e.g., `ls /tmp' will..
9691 wysh ghost lls '!ls ${LS_COLOR_FLAG} -aFlrS'
9692 wysh ghost llS '!ls ${LS_COLOR_FLAG} -aFlS'
9693 wysh ghost ls '!ls ${LS_COLOR_FLAG} -aFrS'
9694 wysh ghost lS '!ls ${LS_COLOR_FLAG} -aFS'
9695 wysh ghost lla '!ls ${LS_COLOR_FLAG} -aFlr'
9696 wysh ghost llA '!ls ${LS_COLOR_FLAG} -aFl'
9697 wysh ghost la '!ls ${LS_COLOR_FLAG} -aFr'
9698 wysh ghost lA '!ls ${LS_COLOR_FLAG} -aF'
9699 wysh ghost ll '!ls ${LS_COLOR_FLAG} -aFltr'
9700 wysh ghost lL '!ls ${LS_COLOR_FLAG} -aFlt'
9701 wysh ghost l '!ls ${LS_COLOR_FLAG} -aFtr'
9702 wysh ghost L '!ls ${LS_COLOR_FLAG} -aFt'
9704 # We don't support gpg(1) directly yet. But simple --clearsign'd
9705 # message parts can be dealt with as follows:
9707 wysh set pipe-text/plain=$'@*#++=@\e
9708 < "${NAIL_FILENAME_TEMPORARY}" awk \e
9709 -v TMPFILE="${NAIL_FILENAME_TEMPORARY}" \e'\e
9711 /^-----BEGIN PGP SIGNED MESSAGE-----/,/^$/{\e
9714 print "--- GPG --verify ---";\e
9715 system("gpg --verify " TMPFILE " 2>&1");\e
9716 print "--- GPG --verify ---";\e
9720 /^-----BEGIN PGP SIGNATURE-----/,\e
9721 /^-----END PGP SIGNATURE-----/{\e
9731 !printf 'Key IDs to gpg --recv-keys: ';\e
9733 gpg --recv-keys ${keyids};
9739 When storing passwords in
9741 appropriate permissions should be set on this file with
9742 .Ql $ chmod 0600 \*(ur .
9745 is available user credentials can be stored in the central
9747 file instead; e.g., here is a different version of the example account
9748 that sets up SMTP and POP3:
9750 .Bd -literal -offset indent
9752 set folder=~/spool/XandeX MAIL=+syste.mbox sent=+sent
9753 set from='Your Name <address@exam.ple>'
9755 # Load an encrypted ~/.netrc by uncommenting the next line
9756 #set netrc-pipe='gpg -qd ~/.netrc.pgp'
9758 set mta=smtps://smtp.yXXXXx.ru:465 \e
9759 smtp-hostname= hostname=yXXXXx.com
9760 set pop3-keepalive=240 pop3-no-apop-pop.yXXXXx.ru
9761 ghost xp fi pop3s://pop.yXXXXx.ru
9770 .Bd -literal -offset indent
9771 machine *.yXXXXx.ru login USER password PASS
9775 This configuration should now work just fine:
9778 .Dl $ echo text | \*(uA -vv -AXandeX -s Subject user@exam.ple
9781 .\" .Ss "Signed and encrypted messages with S/MIME" {{{
9782 .Ss "Signed and encrypted messages with S/MIME"
9784 \*(OP S/MIME provides two central mechanisms:
9785 message signing and message encryption.
9786 A signed message contains some data in addition to the regular text.
9787 The data can be used to verify that the message was sent using a valid
9788 certificate, that the sender's address in the message header matches
9789 that in the certificate, and that the message text has not been altered.
9790 Signing a message does not change its regular text;
9791 it can be read regardless of whether the recipient's software is able to
9795 It is thus usually possible to sign all outgoing messages if so desired.
9796 Encryption, in contrast, makes the message text invisible for all people
9797 except those who have access to the secret decryption key.
9798 To encrypt a message, the specific recipient's public encryption key
9800 It is therefore not possible to send encrypted mail to people unless their
9801 key has been retrieved from either previous communication or public key
9803 A message should always be signed before it is encrypted.
9804 Otherwise, it is still possible that the encrypted message text is
9808 A central concept to S/MIME is that of the certification authority (CA).
9809 A CA is a trusted institution that issues certificates.
9810 For each of these certificates it can be verified that it really
9811 originates from the CA, provided that the CA's own certificate is
9813 A set of CA certificates is usually delivered with OpenSSL and installed
9815 If you trust the source of your OpenSSL software installation,
9816 this offers reasonable security for S/MIME on the Internet.
9818 .Va ssl-no-default-ca
9822 .Va smime-ca-dir . )
9823 In general, a certificate cannot be more secure than the method its CA
9824 certificate has been retrieved with, though.
9825 Thus if you download a CA certificate from the Internet,
9826 you can only trust the messages you verify using that certificate as
9827 much as you trust the download process.
9830 The first thing you need for participating in S/MIME message exchange is
9831 your personal certificate, including a private key.
9832 The certificate contains public information, in particular your name and
9833 your email address(es), and the public key that is used by others to
9834 encrypt messages for you,
9835 and to verify signed messages they supposedly received from you.
9836 The certificate is included in each signed message you send.
9837 The private key must be kept secret.
9838 It is used to decrypt messages that were previously encrypted with your
9839 public key, and to sign messages.
9842 For personal use it is recommended that you get a S/MIME certificate
9843 from one of the major CAs on the Internet using your WWW browser.
9844 Many CAs offer such certificates for free.
9846 .Lk https://www.CAcert.org
9847 which issues client and server certificates to members of their
9848 community for free; their root certificate
9849 .Pf ( Lk https://\:www.cacert.org/\:certs/\:root.crt )
9850 is often not in the default set of trusted CA root certificates, though,
9851 which means you will have to download their root certificate separately
9852 and ensure it is part of our S/MIME certificate validation chain by
9855 or as a vivid member of the
9857 But let's take a step-by-step tour on how to setup S/MIME with
9858 a certificate from CAcert.org despite this situation!
9861 First of all you will have to become a member of the CAcert.org
9862 community, simply by registrating yourself via the web interface.
9863 Once you are, create and verify all email addresses you want to be able
9864 to create signed and encrypted messages for/with using the corresponding
9865 entries of the web interface.
9866 Now ready to create S/MIME certificates, so let's create a new
9867 .Dq client certificate ,
9868 ensure to include all email addresses that should be covered by the
9869 certificate in the following web form, and also to use your name as the
9873 Create a private key and a certificate request on your local computer
9874 (please see the manual pages of the used commands for more in-depth
9875 knowledge on what the used arguments etc. do):
9878 .Dl openssl req -nodes -newkey rsa:4096 -keyout key.pem -out creq.pem
9881 Afterwards copy-and-paste the content of
9883 into the certificate-request (CSR) field of the web form on the
9884 CAcert.org website (you may need to unfold some
9885 .Dq advanced options
9886 to see the corresponding text field).
9887 This last step will ensure that your private key (which never left your
9888 box) and the certificate belong together (through the public key that
9889 will find its way into the certificate via the certificate-request).
9890 You are now ready and can create your CAcert certified certificate.
9891 Download and store or copy-and-paste it as
9896 In order to use your new S/MIME setup you will have to create
9897 a combined private key/public key (certificate) file:
9900 .Dl cat key.pem pub.crt > ME@HERE.com.paired
9903 This is the file \*(UA will work with.
9904 If you have created your private key with a passphrase then \*(UA will
9905 ask you for it whenever a message is signed or decrypted.
9906 Set the following variables to henceforth use S/MIME (setting
9908 is of interest for verification only):
9910 .Bd -literal -offset indent
9911 set smime-ca-file=ALL-TRUSTED-ROOT-CERTS-HERE \e
9912 smime-sign-cert=ME@HERE.com.paired \e
9913 smime-sign-message-digest=SHA256 \e
9918 From each signed message you send, the recipient can fetch your
9919 certificate and use it to send encrypted mail back to you.
9920 Accordingly if somebody sends you a signed message, you can do the same,
9923 command to check the validity of the certificate.
9926 Variables of interest for S/MIME signing:
9930 .Va smime-crl-file ,
9931 .Va smime-no-default-ca ,
9933 .Va smime-sign-cert ,
9934 .Va smime-sign-include-certs
9936 .Va smime-sign-message-digest .
9939 After it has been verified save the certificate via
9941 and tell \*(UA that it should use it for encryption for further
9942 communication with that somebody:
9944 .Bd -literal -offset indent
9946 set smime-encrypt-USER@HOST=FILENAME \e
9947 smime-cipher-USER@HOST=AES256
9951 Additional variables of interest for S/MIME en- and decryption:
9954 .Va smime-encrypt-USER@HOST .
9957 You should carefully consider if you prefer to store encrypted messages
9959 If you do, anybody who has access to your mail folders can read them,
9960 but if you do not, you might be unable to read them yourself later if
9961 you happen to lose your private key.
9964 command saves messages in decrypted form, while the
9968 commands leave them encrypted.
9971 Note that neither S/MIME signing nor encryption applies to message
9972 subjects or other header fields yet.
9973 Thus they may not contain sensitive information for encrypted messages,
9974 and cannot be trusted even if the message content has been verified.
9975 When sending signed messages,
9976 it is recommended to repeat any important header information in the
9980 .\" .Ss "Using CRLs with S/MIME or SSL/TLS" {{{
9981 .Ss "Using CRLs with S/MIME or SSL/TLS"
9983 \*(OP Certification authorities (CAs) issue certificate revocation
9984 lists (CRLs) on a regular basis.
9985 These lists contain the serial numbers of certificates that have been
9986 declared invalid after they have been issued.
9987 Such usually happens because the private key for the certificate has
9989 because the owner of the certificate has left the organization that is
9990 mentioned in the certificate, etc.
9991 To seriously use S/MIME or SSL/TLS verification,
9992 an up-to-date CRL is required for each trusted CA.
9993 There is otherwise no method to distinguish between valid and
9994 invalidated certificates.
9995 \*(UA currently offers no mechanism to fetch CRLs, nor to access them on
9996 the Internet, so you have to retrieve them by some external mechanism.
9999 \*(UA accepts CRLs in PEM format only;
10000 CRLs in DER format must be converted, like, e.\|g.:
10003 .Dl $ openssl crl \-inform DER \-in crl.der \-out crl.pem
10006 To tell \*(UA about the CRLs, a directory that contains all CRL files
10007 (and no other files) must be created.
10012 variables, respectively, must then be set to point to that directory.
10013 After that, \*(UA requires a CRL to be present for each CA that is used
10014 to verify a certificate.
10017 .\" .Ss "Handling spam" {{{
10018 .Ss "Handling spam"
10020 \*(OP \*(UA can make use of several spam interfaces for the purpose of
10021 identification of, and, in general, dealing with spam messages.
10022 A precondition of most commands in order to function is that the
10024 variable is set to one of the supported interfaces.
10025 Once messages have been identified as spam their (volatile)
10027 state can be prompted: the
10031 message specifications will address respective messages and their
10033 entries will be used when displaying the
10035 in the header display.
10040 rates the given messages and sets their
10043 If the spam interface offers spam scores those can also be displayed in
10044 the header display by including the
10054 will interact with the Bayesian filter of the chosen interface and learn
10055 the given messages as
10059 respectively; the last command can be used to cause
10061 of messages; it adheres to their current
10063 state and thus reverts previous teachings.
10068 will simply set and clear, respectively, the mentioned volatile
10070 message flag, without any interface interaction.
10079 requires a running instance of the
10081 server in order to function, started with the option
10083 shall Bayesian filter learning be possible.
10085 .Bd -literal -offset indent
10086 $ spamd -i localhost:2142 -i /tmp/.spamsock -d [-L] [-l]
10087 $ spamd --listen=localhost:2142 --listen=/tmp/.spamsock \e
10088 --daemonize [--local] [--allow-tell]
10092 Thereafter \*(UA can make use of these interfaces:
10094 .Bd -literal -offset indent
10095 $ \*(uA -Sspam-interface=spamc -Sspam-maxsize=500000 \e
10096 -Sspamc-command=/usr/local/bin/spamc \e
10097 -Sspamc-arguments="-U /tmp/.spamsock" -Sspamc-user=
10099 $ \*(uA -Sspam-interface=spamc -Sspam-maxsize=500000 \e
10100 -Sspamc-command=/usr/local/bin/spamc \e
10101 -Sspamc-arguments="-d localhost -p 2142" -Sspamc-user=
10105 Using the generic filter approach allows usage of programs like
10107 Here is an example, requiring it to be accessible via
10110 .Bd -literal -offset indent
10111 $ \*(uA -Sspam-interface=filter -Sspam-maxsize=500000 \e
10112 -Sspamfilter-ham="bogofilter -n" \e
10113 -Sspamfilter-noham="bogofilter -N" \e
10114 -Sspamfilter-nospam="bogofilter -S" \e
10115 -Sspamfilter-rate="bogofilter -TTu 2>/dev/null" \e
10116 -Sspamfilter-spam="bogofilter -s" \e
10117 -Sspamfilter-rate-scanscore="1;^(.+)$"
10121 Because messages must exist on local storage in order to be scored (or
10122 used for Bayesian filter training), it is possibly a good idea to
10123 perform the local spam check last:
10125 .Bd -literal -offset indent
10126 define spamdelhook {
10128 spamset (header x-dcc-brand-metrics "bulk")
10129 # Server-side spamassassin(1)
10130 spamset (header x-spam-flag "YES")
10131 del :s # TODO we HAVE to be able to do `spamrate :u ! :sS'
10132 move :S +maybe-spam
10135 move :S +maybe-spam
10137 set folder-hook-FOLDER=spamdelhook
10141 See also the documentation for the variables
10142 .Va spam-interface , spam-maxsize ,
10143 .Va spamc-command , spamc-arguments , spamc-user ,
10144 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
10147 .Va spamfilter-rate-scanscore .
10155 In general it is a good idea to turn on
10161 twice) if something doesn't work well.
10162 Very often a diagnostic message can be produced that leads to the
10163 problems' solution.
10165 .\" .Ss "\*(UA shortly hangs on startup" {{{
10166 .Ss "\*(UA shortly hangs on startup"
10168 This can have two reasons, one is the necessity to wait for a file lock
10169 and can't be helped, the other being that \*(UA calls the function
10171 in order to query the nodename of the box (sometimes the real one is
10172 needed instead of the one represented by the internal variable
10174 You may have varying success by ensuring that the real hostname and
10178 or, more generally, that the name service is properly setup \(en
10181 return what you'd expect?
10182 Does this local hostname has a domain suffix?
10183 RFC 6762 standardized the link-local top-level domain
10187 .\" .Ss "I can't login to Google mail aka GMail" {{{
10188 .Ss "I can't login to Google mail aka GMail"
10190 Since 2014 some free service providers classify programs as
10192 unless they use a special authentification method (OAuth 2.0) which
10193 wasn't standardized for non-HTTP protocol authentication token query
10194 until August 2015 (RFC 7628).
10197 Different to Kerberos / GSSAPI, which is developed since the mid of the
10198 1980s, where a user can easily create a local authentication ticket for
10199 her- and himself with the locally installed
10201 program, that protocol has no such local part but instead requires
10202 a world-wide-web query to create or fetch a token; since there is no
10203 local cache this query has to be performed whenever \*(UA is invoked
10204 from the command line (in interactive sessions situation may differ).
10207 \*(UA doesn't support OAuth.
10208 Because of this it is necessary to declare \*(UA a
10209 .Dq less secure app
10210 (on the providers account web page) in order to read and send mail.
10211 However, it also seems possible to take the following steps instead:
10216 give the provider the number of a mobile phone,
10219 .Dq 2-Step Verification ,
10221 create an application specific password (16 characters), and
10223 use that special password instead of your real Google account password in
10224 \*(UA (for more on that see the section
10225 .Sx "On URL syntax and credential lookup" ) .
10229 .\" .Ss "Not \(dqdefunctional\(dq, but the editor key won't work" {{{
10230 .Ss "Not \(dqdefunctional\(dq, but the editor key won't work"
10232 It can happen that the terminal library (see
10233 .Sx "On terminal control and line editor",
10236 reports different codes than the terminal really sends, in which case
10237 \*(UA will tell that a key binding is functional, but won't be able to
10238 recognize it because the received data doesn't match anything expected.
10239 The verbose listing of
10241 ings will show the byte sequences that are expected.
10244 To overcome the situation, use, e.g., the program
10246 in conjunction with the
10248 flag if available, to see the byte sequences which are actually produced
10249 by keypresses, and use the variable
10251 to make \*(UA aware of them.
10252 E.g., the terminal this is typed on produces some false sequences, here
10253 an example showing the shifted home key:
10255 .Bd -literal -offset indent
10258 # 1B 5B=[ 31=1 3B=; 32=2 48=H
10263 ? \*(uA -v -Stermcap='kHOM=\eE[H'
10272 .\" .Sh "SEE ALSO" {{{
10282 .Xr spamassassin 1 ,
10291 .Xr mailwrapper 8 ,
10296 .\" .Sh HISTORY {{{
10299 M. Douglas McIlroy writes in his article
10300 .Dq A Research UNIX Reader: Annotated Excerpts \
10301 from the Programmer's Manual, 1971-1986
10304 command already appeared in First Edition
10308 .Bd -ragged -offset indent
10309 Electronic mail was there from the start.
10310 Never satisfied with its exact behavior, everybody touched it at one
10311 time or another: to assure the safety of simultaneous access, to improve
10312 privacy, to survive crashes, to exploit uucp, to screen out foreign
10313 freeloaders, or whatever.
10314 Not until v7 did the interface change (Thompson).
10315 Later, as mail became global in its reach, Dave Presotto took charge and
10316 brought order to communications with a grab-bag of external networks
10322 Mail was written in 1978 by Kurt Shoens and developed as part of the
10325 distribution until 1995.
10326 Mail has then seen further development in open source
10328 variants, noticeably by Christos Zoulas in
10330 Basing upon this Nail, later Heirloom Mailx, was developed by Gunnar
10331 Ritter in the years 2000 until 2008.
10332 Since 2012 S-nail is maintained by Steffen (Daode) Nurpmeso.
10333 This man page is derived from
10334 .Dq The Mail Reference Manual
10335 that was originally written by Kurt Shoens.
10341 .An "Kurt Shoens" ,
10342 .An "Edward Wang" ,
10343 .An "Keith Bostic" ,
10344 .An "Christos Zoulas" ,
10345 .An "Gunnar Ritter" ,
10346 .An "Steffen Nurpmeso" Aq Mt s-nail-users@lists.sourceforge.net
10348 .Mt s-mailx@sdaoden.eu ) .
10351 .\" .Sh CAVEATS {{{
10354 \*(ID Interrupting an operation via
10358 is often problematic: many library functions cannot deal with the
10360 that this software (still) performs.
10363 The SMTP and POP3 protocol support of \*(UA is very basic.
10364 Also, if it fails to contact its upstream SMTP server, it will not make
10365 further attempts to transfer the message at a later time (setting
10370 If this is a concern, it might be better to set up a local SMTP server
10371 that is capable of message queuing.
10377 After deleting some message of a POP3 mailbox the header summary falsely
10378 claims that there are no messages to display, you need to perform
10379 a scroll or dot movement to restore proper state.
10381 In threaded display a power user may encounter crashes very
10382 occasionally (this is may and very).
10386 in the source repository lists future directions.