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 Terminal control will be realized through one of the standard
2178 libraries, either the
2180 or, alternatively, the
2182 both of which will be initialized to work with the environment variable
2184 Terminal control will enhance or enable interactive usage aspects, e.g.,
2185 .Sx "Coloured display" ,
2186 and extend behaviour of the Mailx-Line-Editor (MLE), which may learn the
2187 byte-sequences of keys like the cursor and function keys, and which will
2188 automatically enter the so-called
2190 alternative screen shall the terminal support it.
2191 The internal variable
2193 can be used to overwrite settings or to learn (correct(ed)) keycodes.
2194 Actual interaction with the chosen library can be disabled completely by
2195 setting the internal variable
2196 .Va termcap-disable ;
2198 will be queried regardless, even if the \*(OPal support for the
2199 libraries has not been enabled at configuration time.
2202 \*(OP The builtin \*(UA Mailx-Line-Editor (MLE) should work in all
2203 environments which comply to the ISO C standard
2205 and will support wide glyphs if possible (the necessary functionality
2206 had been removed from ISO C, but was included in
2208 Prevent usage of a line editor in interactive mode by setting the
2210 .Va line-editor-disable .
2211 Especially if the \*(OPal terminal control support is missing setting
2212 entries in the internal variable
2214 will help shall the MLE misbehave, see there for more.
2215 The MLE can support a little bit of
2221 feature is available then input from line editor prompts will be saved
2222 in a history list that can be searched in and be expanded from.
2223 Such saving can be prevented by prefixing input with any amount of
2225 Aspects of history, like allowed content and maximum size, as well as
2226 whether history shall be saved persistently, can be configured with the
2230 .Va history-gabby-persist
2235 The MLE supports a set of editing and control commands.
2236 By default (as) many (as possible) of these will be assigned to a set of
2237 single-letter control codes, which should work on any terminal.
2240 command is available then the MLE commands can also be accessed freely
2241 by assigning the command name, which is shown in parenthesis in the list
2242 below, to any desired key-sequence, and the MLE will instead and also use
2244 to establish its builtin key bindings
2245 (more of them if the \*(OPal terminal control is available),
2246 an action which can then be suppressed completely by setting
2247 .Va line-editor-no-defaults .
2248 The following uses the
2250 ell-style quote notation that is documented in the introductional
2253 combinations not mentioned either cause job control signals or don't
2254 generate a (unique) keycode:
2258 .Bl -tag -compact -width "Ql _M"
2260 Go to the start of the line
2261 .Pf ( Cd mle-go-home ) .
2264 Move the cursor backward one character
2265 .Pf ( Cd mle-go-bwd ) .
2268 Forward delete the character under the cursor;
2269 quits \*(UA if used on the empty line unless the
2272 .Pf ( Cd mle-del-fwd ) .
2275 Go to the end of the line
2276 .Pf ( Cd mle-go-end ) .
2279 Move the cursor forward one character
2280 .Pf ( Cd mle-go-fwd ) .
2283 Cancel current operation, full reset.
2284 If there is an active history search or tabulator expansion then this
2285 command will first reset that, reverting to the former line content;
2286 thus a second reset is needed for a full reset in this case
2287 .Pf ( Cd mle-reset ) .
2290 Backspace: backward delete one character
2291 .Pf ( Cd mle-del-bwd ) .
2295 Horizontal tabulator:
2296 try to expand the word before the cursor, also supporting \*(UA
2299 .Pf ( Cd mle-complete ) .
2301 .Cd mle-quote-rndtrip .
2305 commit the current line
2306 .Pf ( Cd mle-commit ) .
2309 Cut all characters from the cursor to the end of the line
2310 .Pf ( Cd mle-snarf-end ) .
2314 .Pf ( Cd mle-repaint ) .
2317 \*(OP Go to the next history entry
2318 .Pf ( Cd mle-hist-fwd ) .
2325 \*(OP Go to the previous history entry
2326 .Pf ( Cd mle-hist-bwd ) .
2329 Toggle roundtrip mode shell quotes, where produced,
2331 .Pf ( Cd mle-quote-rndtrip ) .
2332 This setting is temporary, and will be forgotten once the command line
2336 \*(OP Complete the current line from (the remaining) older history entries
2337 .Pf ( Cd mle-hist-srch-bwd ) .
2340 \*(OP Complete the current line from (the remaining) newer history entries
2341 .Pf ( Cd mle-hist-srch-fwd ) .
2344 Paste the snarf buffer
2345 .Pf ( Cd mle-paste ) .
2352 .Pf ( Cd mle-snarf-line ) .
2355 Prompts for a Unicode character (its hexadecimal number) to be inserted
2356 .Pf ( Cd mle-prompt-char ) .
2357 Note this command needs to be assigned to a single-letter control code
2358 in order to become recognized and executed during input of
2359 a key-sequence (only four single-letter control codes can be used for
2360 that shortcut purpose); this control code is special-treated and can't
2361 be part of any other sequence, because any occurrence will perform the
2363 function immediately.
2366 Cut the characters from the one preceding the cursor to the preceding
2368 .Pf ( Cd mle-snarf-word-bwd ) .
2371 Move the cursor forward one word boundary
2372 .Pf ( Cd mle-go-word-fwd ) .
2375 Move the cursor backward one word boundary
2376 .Pf ( Cd mle-go-word-bwd ) .
2379 Escape: reset a possibly used multibyte character input state machine
2380 and \*(OPally a lingering, incomplete key binding
2381 .Pf ( Cd mle-cancel ) .
2382 This command needs to be assigned to a single-letter control code in
2383 order to become recognized and executed during input of a key-sequence
2384 (only four single-letter control codes can be used for that shortcut
2386 This control code may also be part of a multi-byte sequence, but if
2387 a sequence is active and the very control code is currently also an
2388 expected input, then it will first be consumed by the active sequence.
2403 Cut the characters from the one after the cursor to the succeeding word
2405 .Pf ( Cd mle-snarf-word-fwd ) .
2415 this will immediately reset a possibly active search etc.
2419 ring the audible bell.
2423 .\" .Ss "Coloured display" {{{
2424 .Ss "Coloured display"
2426 \*(OP \*(UA can be configured to support a coloured display and font
2427 attributes by emitting ANSI / ISO 6429 SGR (select graphic rendition)
2429 Usage of colours and font attributes solely depends upon the
2430 capability of the detected terminal type that is defined by the
2431 environment variable
2433 and which can be fine-tuned by the user via the internal variable
2437 On top of what \*(UA knows about the terminal the boolean variable
2439 defines whether the actually applicable colour and font attribute
2440 sequences should also be generated when output is going to be paged
2441 through the external program defined by the environment variable
2446 This is not enabled by default because different pager programs need
2447 different command line switches or other configuration in order to
2448 support those sequences.
2449 \*(UA however knows about some widely used pagers and in a clean
2450 environment it is often enough to simply set
2452 please refer to that variable for more on this topic.
2457 is set then any active usage of colour and font attribute sequences
2458 is suppressed, but without affecting possibly established
2463 To define and control colours and font attributes a single multiplexer
2464 command family exists:
2466 shows or defines colour mappings for the given colour type (e.g.,
2469 can be used to remove mappings of a given colour type.
2470 Since colours are only available in interactive mode, it may make
2471 sense to conditionalize the colour setup by encapsulating it with
2474 .Bd -literal -offset indent
2475 if terminal && $features =@ +colour
2476 colour iso view-msginfo ft=bold,fg=green
2477 colour iso view-header ft=bold,fg=red "from,subject"
2478 colour iso view-header fg=red
2480 uncolour iso view-header from,subject
2481 colour iso view-header ft=bold,fg=magenta,bg=cyan
2482 colour 256 view-header ft=bold,fg=208,bg=230 subject,from
2483 colour mono view-header ft=bold
2484 colour mono view-header ft=bold,ft=reverse subject,from
2488 .\" }}} (DESCRIPTION)
2491 .\" .Sh COMMANDS {{{
2494 Each command is typed on a line by itself,
2495 and may take arguments following the command word.
2496 Command names may be abbreviated, in which case the first command that
2497 matches the given prefix will be used.
2500 can be used to show the list of all commands, either alphabetically
2501 sorted or in prefix search order (these don't match, also because the
2502 POSIX standard prescribes a set of abbreviations); a more verbose
2503 listing will be produced if either of
2508 \*(OPally the command
2512 when given an argument, will show a documentation string for the
2513 command matching the expanded argument, as in
2515 which should be a shorthand of
2519 For commands which take message lists as arguments, the next message
2520 forward that satisfies the command's requirements will be used shall no
2521 explicit message list have been specified.
2522 If there are no messages forward of the current message,
2523 the search proceeds backwards,
2524 and if there are no good messages at all,
2525 \*(UA shows an error message and aborts the command.
2526 \*(ID Non-message-list arguments can be quoted using the following methods:
2529 .Bl -bullet -compact -offset indent
2531 An argument can be enclosed between paired double-quotes
2536 any white space, shell word expansion, or reverse solidus characters
2537 (except as described next) within the quotes are treated literally as
2538 part of the argument.
2539 A double-quote will be treated literally within single-quotes and vice
2541 Inside such a quoted string the actually used quote character can be
2542 used nonetheless by escaping it with a reverse solidus
2548 An argument that is not enclosed in quotes, as above, can usually still
2549 contain space characters if those spaces are reverse solidus escaped, as in
2553 A reverse solidus outside of the enclosing quotes is discarded
2554 and the following character is treated literally as part of the argument.
2559 Some commands which don't take message-list arguments can also be
2560 prefixed with the special keyword
2562 to choose \*(INible behaviour, and some new commands support only the
2563 new quoting style (without that keyword) and are flagged \*(NQ.
2564 In the future \*(UA will (mostly) use
2566 compatible argument parsing:
2567 Non-message-list arguments can be quoted using the following shell-style
2568 mechanisms: the escape character, single-quotes, double-quotes and
2569 dollar-single-quotes; any unquoted number sign
2571 starts a comment that ends argument processing.
2572 The overall granularity of error reporting and diagnostics, also
2573 regarding function arguments and their content, will improve.
2577 .Bl -bullet -compact -offset indent
2579 The literal value of any character can be preserved by preceding it
2580 with the escape character reverse solidus
2584 will cause variable expansion of the given name: \*(UA
2585 .Sx "INTERNAL VARIABLES"
2588 (shell) variables can be accessed through this mechanism, brace
2589 enclosing the name is supported.
2592 Arguments which are enclosed in
2593 .Ql 'single-\:quotes'
2594 retain their literal value.
2595 A single-quote cannot occur within single-quotes.
2598 The literal value of all characters enclosed in
2599 .Ql \(dqdouble-\:quotes\(dq
2600 is retained, with the exception of dollar
2602 which will cause variable expansion, as above, backquote (grave accent)
2604 (which not yet means anything special), reverse solidus
2606 which will escape any of the characters dollar
2608 (to prevent variable expansion), backquote (grave accent)
2612 (to prevent ending the quote) and reverse solidus
2614 (to prevent escaping, i.e., to embed a reverse solidus character as-is),
2615 but has no special meaning otherwise.
2618 Arguments enclosed in
2619 .Ql $'dollar-\:single-\:quotes'
2620 extend normal single quotes in that reverse solidus escape sequences are
2621 expanded as follows:
2623 .Bl -tag -compact -width "Ql \eNNN"
2629 an escape character.
2631 an escape character.
2643 emits a reverse solidus character.
2647 double quote (escaping is optional).
2649 eight-bit byte with the octal value
2651 (one to three octal digits), optionally with an additional
2654 A 0 byte will suppress further output for the quoted argument.
2656 eight-bit byte with the hexadecimal value
2658 (one or two hexadecimal characters).
2659 A 0 byte will suppress further output for the quoted argument.
2661 the Unicode / ISO-10646 character with the hexadecimal codepoint value
2663 (one to eight hexadecimal digits) \(em note that Unicode defines the
2664 maximum code to be ever supported as
2669 This escape is only supported in locales which support Unicode (see
2670 .Sx "Character sets" ) ,
2671 in other cases the sequence will remain unexpanded unless the given code
2672 point is ASCII compatible.
2673 The character NUL will suppress further output for the quoted argument.
2677 except it takes only one to four hexadecimal digits.
2682 This is a mechanism that allows usage of the non-printable (ASCII and
2683 compatible) control codes 0 to 31: to be able to create a printable
2684 representation the numeric value 64 is added to the control code of
2685 desire, and the resulting ASCII character set code point is then
2686 printed, e.g., BEL is
2687 .Ql 7 + 64 = 71 = G .
2688 Often circumflex notation is used for the visualization purpose, e.g,
2690 but the reverse solid notation has been standardized:
2692 The control code NUL
2694 ends argument processing without producing further output.
2696 Non-standard extension: expand the given variable name, as above.
2697 Brace enclosing the name is supported.
2699 Not yet supported, just to raise awareness: Non-standard extension.
2705 .Sy Compatibility notes:
2706 \*(ID Note these are new mechanisms which are not supported by all
2708 Round-tripping (feeding in things shown in list modes again) are not yet
2709 stable or possible at all.
2710 On new-style command lines it is wise to quote semicolon
2714 characters in order to ensure upward compatibility: the author would
2715 like to see things like
2716 .Ql ? echo $'trouble\etahead' | cat >> in_the_shell.txt
2718 .Ql ? top 2 5 10; type 3 22
2720 Before \*(UA will switch entirely to shell-style argument parsing there
2721 will be a transition phase where using
2723 will emit obsoletion warnings.
2724 E.g., the following are equivalent:
2726 .Bd -literal -offset indent
2727 mlist @any\e\e.where\e\e.example\e\e.com
2728 wysh mlist '@any\e.where\e.example\e.com' # This is a comment
2729 wysh mlist $'@any\e\e\ex2Ewhere\e\e.example\e\e\e56com' # A comment
2730 wysh mlist "@any\e.where\e.example\e.com"
2734 In any event an unquoted reverse solidus at the end of a command line is
2735 discarded and the next line continues the command.
2736 \*(ID Note that line continuation is handled before the above parsing is
2737 applied, i.e., the parsers documented above will see merged lines.
2738 Filenames, where expected, are subsequently subjected to the following
2739 transformations, in sequence:
2742 .Bl -bullet -compact -offset indent
2744 If the filename begins with an unquoted plus sign, and the
2746 variable is defined,
2747 the plus sign will be replaced by the value of the
2749 variable followed by a solidus.
2752 variable is unset or is set to null, the filename will be unchanged.
2755 Meta expansions are applied to the filename: a leading tilde
2757 character will be replaced by the expansion of
2759 except when followed by a valid user name, in which case the home
2760 directory of the given user is used instead.
2765 will be replaced by the expansion of the variable, if possible; \*(UA
2766 .Sx "INTERNAL VARIABLES"
2769 (shell) variables can be accessed through this mechanism, and the usual
2770 escape mechanism has to be applied to prevent interpretation.
2771 If the fully expanded filename results in multiple pathnames and the
2772 command is expecting only one file, an error results.
2774 In interactive context, in order to allow simple value acceptance (via
2776 arguments will usually be displayed in a properly quoted form, e.g., a file
2777 .Ql diet\e is \ecurd.txt
2779 .Ql 'diet\e is \ecurd.txt' .
2783 The following commands are available:
2785 .Bl -tag -width ".Ic _ccount"
2792 ) command which follows.
2796 The comment-command causes the entire line to be ignored.
2798 this really is a normal command which' purpose is to discard its
2801 indicating special character, which means that, e.g., trailing comments
2802 on a line are not possible.
2806 Goes to the next message in sequence and types it
2812 Display the preceding message, or the n'th previous message if given
2813 a numeric argument n.
2817 Show the current message number (the
2822 Show a brief summary of commands.
2823 \*(OP Given an argument a synopsis for the command in question is
2824 shown instead; commands can be abbreviated in general and this command
2825 can be used to see the full expansion of an abbreviation including the
2826 synopsis, try, e.g.,
2831 and see how the output changes.
2841 Interprets the remainder of the word as a macro name and passes it
2846 is a shorter synonym for
2847 .Ql call Ar mymacro .
2851 (ac) Creates, selects or lists (an) account(s).
2852 Accounts are special incarnations of
2854 macros and group commands and variable settings which together usually
2855 arrange the environment for the purpose of creating an email account.
2856 Different to normal macros settings which are covered by
2858 \(en here by default enabled! \(en will not be reverted before the
2863 (case-insensitive) always exists, and all but it can be deleted via
2866 Without arguments a listing of all defined accounts is shown.
2867 With one argument the given account is activated: the system
2869 box of that account will be activated (as via
2871 and a possibly installed
2874 The two argument form is identical to defining a macro as via
2876 .Bd -literal -offset indent
2878 set folder=~/mail MAIL=+syste.mbox record=+sent.mbox
2879 set from='myname@myisp.example (My Name)'
2880 set mta=smtp://mylogin@smtp.myisp.example
2886 (a) With no arguments, shows all currently-defined aliases.
2887 With one argument, shows that alias.
2888 With more than one argument,
2889 creates a new alias or appends to an existing one.
2891 can be used to delete aliases.
2895 (alt) Manage a list of alternate addresses / names of the active user,
2896 members of which will be removed from recipient lists when replying to
2899 variable is not set).
2900 If arguments are given the set of alternate names is replaced by them,
2901 without arguments the current set is displayed.
2905 Takes a message list and marks each message as having been answered.
2906 This mark has no technical meaning in the mail system;
2907 it just causes messages to be marked in the header summary,
2908 and makes them specially addressable.
2913 \*(OP\*(NQ The bind command extends the MLE (see
2914 .Sx "On terminal control and line editor" )
2915 with freely configurable key bindings.
2916 With one argument all bindings for the given context are shown,
2917 specifying an asterisk
2919 will show the bindings of all contexts; a more verbose listing will be
2920 produced if either of
2925 With two or more arguments a binding is (re)established:
2926 the first argument is the context to which the binding shall apply,
2927 the second argument is a comma-separated list of the
2929 which form the binding, and any remaining arguments form the expansion.
2930 To indicate that a binding shall not be auto-committed, but that the
2931 expansion shall instead be furtherly editable by the user, an at-sign
2933 (that will be removed) can be placed last in the expansion, from which
2934 leading and trailing whitespace will finally be removed.
2937 Contexts define when a binding applies, i.e., a binding won't be seen
2938 unless the context for which it is defined for is currently active.
2939 This is not true for the binding
2941 which always applies, but which will be searched secondarily to a more
2942 specialized context and may thus have some or all of its key bindings
2943 transparently replaced by equal bindings of more specialized contexts.
2944 The available contexts are
2946 which always applies, and
2948 which applies to compose-mode.
2952 which form the binding are specified as a comma-separated list of
2953 byte-sequences, where each list entry corresponds to one key(press).
2954 \*(OPally a list entry may, indicated by a leading colon character
2956 also refer to the name of a terminal capability;
2957 several dozen names will be compiled into \*(UA and may be specified
2960 or, if existing, by their
2962 name, regardless of the actually used terminal control library.
2963 It is however possible to use any capability, as long as the name is
2964 resolvable by the control library or defined in the internal variable
2966 Input sequences are not case-normalized, so that an exact match is
2967 required to update or remove a binding.
2970 .Bd -literal -offset indent
2971 bind base $'\eE',d mle-snarf-word-fwd # Esc(ape)
2972 bind base $'\eE',$'\ec?' mle-snarf-word-bwd # Esc, Delete
2973 bind compose :kf1 ~e
2974 bind base $'\ecA',:khome,w 'echo An editable binding@'
2975 bind base a,b,c rm -rf / @ # Another editable binding
2979 Note that the entire comma-separated list is first parsed (over) as a
2980 shell-token with whitespace as the field separator, before being parsed
2981 and expanded for real with comma as the field separator, therefore
2982 whitespace needs to be properly quoted:
2983 shell-style quoting is documented in the introductional section of
2985 Using Unicode reverse solidus escape sequences renders a binding
2986 defunctional if the locale doesn't support Unicode (see
2987 .Sx "Character sets" ) ,
2988 and using terminal capabilities does so if no terminal control support
2989 is (currently) available.
2992 The following terminal capability names are builtin and can be used in
2994 or (if available) the two-letter
2996 notation regardless of the actually used library.
2997 See the respective manual for a list of capabilities.
3000 can be used to show all the capabilities of
3002 or the given terminal type;
3005 flag will also show supported (non-standard) extensions.
3008 .Bl -tag -compact -width kcuuf_or_kcuuf
3009 .It Cd kbs Ns \0or Cd kb
3011 .It Cd kdch1 Ns \0or Cd kD
3013 .It Cd kDC Ns \0or Cd *4
3014 \(em shifted variant.
3015 .It Cd kel Ns \0or Cd kE
3016 Clear to end of line.
3017 .It Cd kext Ns \0or Cd @9
3019 .It Cd kich1 Ns \0or Cd kI
3021 .It Cd kIC Ns \0or Cd #3
3022 \(em shifted variant.
3023 .It Cd khome Ns \0or Cd kh
3025 .It Cd kHOM Ns \0or Cd #2
3026 \(em shifted variant.
3027 .It Cd kend Ns \0or Cd @7
3029 .It Cd knp Ns \0or Cd kN
3031 .It Cd kpp Ns \0or Cd kP
3033 .It Cd kcub1 Ns \0or Cd kl
3034 Left cursor (with more modifiers: see below).
3035 .It Cd kLFT Ns \0or Cd #4
3036 \(em shifted variant.
3037 .It Cd kcuf1 Ns \0or Cd kr
3038 Right cursor (ditto).
3039 .It Cd kRIT Ns \0or Cd %i
3040 \(em shifted variant.
3041 .It Cd kcud1 Ns \0or Cd kd
3042 Down cursor (ditto).
3044 \(em shifted variant (only terminfo).
3045 .It Cd kcuu1 Ns \0or Cd ku
3048 \(em shifted variant (only terminfo).
3049 .It Cd kf0 Ns \0or Cd k0
3051 Add one for each function key up to
3056 .It Cd kf10 Ns \0or Cd k;
3058 .It Cd kf11 Ns \0or Cd F1
3060 Add one for each function key up to
3068 Some terminals support key-modifier combination extensions, e.g.,
3070 For example, the delete key,
3072 in its shifted variant, the name is mutated to
3074 then a number is appended for the states
3086 .Ql Shift+Alt+Control
3088 The same for the left cursor key,
3090 .Cd KLFT , KLFT3 , KLFT4 , KLFT5 , KLFT6 , KLFT7 , KLFT8 .
3093 Key bindings can be removed with the command
3095 It is advisable to use an initial escape or other control character (e.g.,
3097 for bindings which describe user key combinations (as opposed to purely
3098 terminal capability based ones), in order to avoid ambiguities whether
3099 input belongs to key sequences or not; it also reduces search time.
3102 may help shall keys and sequences be falsely recognized.
3107 Calls a macro that has been created via
3112 (ch) Change the working directory to
3114 or the given argument.
3120 \*(OP Only applicable to S/MIME signed messages.
3121 Takes a message list and a file name and saves the certificates
3122 contained within the message signatures to the named file in both
3123 human-readable and PEM format.
3124 The certificates can later be used to send encrypted messages to the
3125 respective message senders by setting
3126 .Va smime-encrypt-USER@HOST
3131 (ch) Change the working directory to
3133 or the given argument.
3139 Only applicable to threaded mode.
3140 Takes a message list and makes all replies to these messages invisible
3141 in header summaries, unless they are in state
3147 \*(OP\*(NQ Manage colour mappings for the type of colour given as the
3148 (case-insensitive) first argument, which must be one of
3150 for 256-colour terminals,
3155 for the standard 8-colour ANSI / ISO 6429 color palette and
3159 for monochrome terminals.
3160 Monochrome terminals cannot deal with colours, but only (some) font
3164 Without further arguments the list of all currently defined mappings
3165 for the given colour type is shown (as a special case giving
3169 will iterate over all types in order).
3170 Otherwise the second argument defines the mappable slot, the third
3171 argument a (comma-separated list of) colour and font attribute
3172 specification(s), and the optional fourth argument can be used to
3173 specify a precondition: if conditioned mappings exist they are tested in
3174 (creation) order unless a (case-insensitive) match has been found, and
3175 the default mapping (if any has been established) will only be chosen as
3177 The types of precondition available depend on the mappable slot, the
3178 following of which exist:
3181 Mappings prefixed with
3183 are used for the \*(OPal builtin Mailx-Line-Editor (MLE, see
3184 .Sx "On terminal control and line editor" )
3185 and don't support preconditions.
3187 .Bl -tag -compact -width view-partinfo
3189 This mapping is used for the position indicator that is visible when
3190 a line cannot be fully displayed on the screen.
3197 Mappings prefixed with
3199 are used in header summaries, and they all understand the preconditions
3201 (the current message) and
3203 for elder messages (only honoured in conjunction with
3204 .Va datefield-markout-older ) .
3206 .Bl -tag -compact -width view-partinfo
3208 This mapping is used for the
3210 that can be created with the
3214 formats of the variable
3217 For the complete header summary line except the
3219 and the thread structure.
3221 For the thread structure which can be created with the
3223 format of the variable
3228 Mappings prefixed with
3230 are used when displaying messages.
3232 .Bl -tag -compact -width view-partinfo
3234 This mapping is used for so-called
3236 lines, which are MBOX file format specific header lines.
3239 A comma-separated list of headers to which the mapping applies may be
3240 given as a precondition; if the \*(OPal regular expression support is
3241 available then if any of the
3243 (extended) regular expression characters is seen the precondition will
3244 be evaluated as (an extended) one.
3246 For the introductional message info line.
3247 .It Cd view-partinfo
3248 For MIME part info lines.
3252 The following (case-insensitive) colour definitions and font attributes
3253 are understood, multiple of which can be specified in a comma-separated
3263 It is possible (and often applicable) to specify multiple font
3264 attributes for a single mapping.
3267 foreground colour attribute:
3277 To specify a 256-color mode a decimal number colour specification in
3278 the range 0 to 255, inclusive, is supported, and interpreted as follows:
3280 .Bl -tag -compact -width "999 - 999"
3282 the standard ISO 6429 colors, as above.
3284 high intensity variants of the standard colors.
3286 216 colors in tuples of 6.
3288 grayscale from black to white in 24 steps.
3290 .Bd -literal -offset indent
3292 fg() { printf "\e033[38;5;${1}m($1)"; }
3293 bg() { printf "\e033[48;5;${1}m($1)"; }
3295 while [ $i -lt 256 ]; do fg $i; i=$(($i + 1)); done
3296 printf "\e033[0m\en"
3298 while [ $i -lt 256 ]; do bg $i; i=$(($i + 1)); done
3299 printf "\e033[0m\en"
3303 background colour attribute (see
3305 for possible values).
3309 Mappings may be removed with the command
3311 For a generic overview see the section
3312 .Sx "Coloured display" .
3317 (C) Copy messages to files whose names are derived from the author of
3318 the respective message and don't mark them as being saved;
3319 otherwise identical to
3324 (c) Copy messages to the named file and don't mark them as being saved;
3325 otherwise identical to
3330 \*(NQ With no arguments, shows all currently-defined custom headers.
3331 With one argument, shows that custom header.
3332 With more than one argument, creates a new or replaces an existing
3333 custom header with the name given as the first argument, the content of
3334 which being defined by the concatenated remaining arguments.
3336 can be used to delete custom headers.
3337 \*(ID Overwriting of automatically managed headers is neither supported
3339 Defined custom headers will be injected into newly composed or forwarded
3342 .Dl customhdr OpenPGP id=12345678; url=http://www.YYY.ZZ
3346 may also be used to inject custom headers; it is covered by
3351 Show the name of the current working directory.
3355 \*(OP For unencrypted messages this command is identical to
3357 Encrypted messages are first decrypted, if possible, and then copied.
3361 \*(OP For unencrypted messages this command is identical to
3363 Encrypted messages are first decrypted, if possible, and then copied.
3367 Without arguments the current list of macros, including their content,
3368 is shown, otherwise a macro is defined.
3369 A macro definition is a sequence of commands in the following form:
3370 .Bd -literal -offset indent
3379 A defined macro can be invoked explicitly by using the
3383 commands, or implicitly if a macro hook is triggered, e.g., a
3385 Note that interpretation of
3387 depends on how (i.e.,
3389 normal macro, folder hook, hook, account switch) the macro is invoked.
3390 Macros can be deleted via
3394 Macro behaviour, including option localization, will change in v15.
3395 Please be aware of that and possibly embed a version check in a resource
3400 (d) Marks the given message list as
3402 Deleted messages will neither be saved in
3404 nor will they be available for most other commands.
3416 Deletes the current message and displays the next message.
3417 If there is no next message, \*(UA says
3424 up or down by one message when given
3428 argument, respectively.
3432 Takes a message list and marks each given message as a draft.
3433 This mark has no technical meaning in the mail system;
3434 it just causes messages to be marked in the header summary,
3435 and makes them specially addressable.
3439 (ec) Echoes its arguments after applying
3441 expansions and filename transformations, as documented for
3446 (e) Point the text editor (as defined in
3448 at each message from the given list in turn.
3449 Modified contents are discarded unless the
3456 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3457 conditional \(em if the condition of a preceding
3459 was false, check the following condition and execute the following block
3460 if it evaluates true.
3465 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3466 conditional \(em if none of the conditions of the preceding
3470 commands was true, the
3476 (en) Marks the end of an
3477 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3478 conditional execution block.
3483 \*(NQ \*(UA has a strict notion about which variables are
3484 .Sx "INTERNAL VARIABLES"
3485 and which are managed in the program
3487 Since some of the latter are a vivid part of \*(UAs functioning,
3488 however, they are transparently integrated into the normal handling of
3489 internal variables via
3493 To integrate other environment variables of choice into this
3494 transparent handling, and also to export internal variables into the
3495 process environment where they normally are not, a
3497 needs to become established with this command, as in, e.g.,
3500 .Dl environ link PERL5LIB from TZ
3503 Afterwards changing such variables with
3505 will cause automatic updates of the program environment, and therefore
3506 be inherited by newly created child processes.
3507 Sufficient system support provided (it was in BSD as early as 1987, and
3508 is standardized since Y2K) removing such variables with
3510 will remove them also from the program environment, but in any way
3511 the knowledge they ever have been
3514 Note this implies that
3516 may cause loss of links.
3521 will remove an existing link, but leaves the variables as such intact.
3522 Additionally the subcommands
3526 are provided, which work exactly the same as the documented commands
3530 but (additionally) link the variable(s) with the program environment and
3531 thus immediately export them to, or remove them from (if possible),
3532 respectively, the program environment.
3537 \*(OP Since \*(UA uses the console as a user interface it can happen
3538 that messages scroll by too fast to become recognized.
3539 Optionally an error message ring queue is available which stores
3540 duplicates of any error message and notifies the user in interactive
3541 sessions whenever a new error has occurred.
3542 The queue is finite: if its maximum size is reached any new message
3543 replaces the eldest.
3546 can be used to manage this message queue: if given
3548 or no argument the queue will be displayed and cleared,
3550 will only clear all messages from the queue.
3554 (ex or x) Exit from \*(UA without changing the active mailbox and skip
3555 any saving of messages in
3557 as well as a possibly tracked line editor history file.
3561 Show the list of features that have been compiled into \*(UA.
3562 (Outputs the contents of the variable
3569 but open the mailbox readonly.
3573 (fi) The file command switches to a new mailbox.
3574 Without arguments it shows status information of the current mailbox.
3575 If an argument is given, it will write out changes (such as deletions)
3576 the user has made and open a new mailbox.
3577 Some special conventions are recognized for the
3581 .Bl -tag -compact -offset indent -width ".Ar %:__lespec"
3583 (number sign) means the previous file,
3585 (percent sign) means the invoking user's system
3589 means the primary system mailbox of
3591 (and never the value of
3593 regardless of its actual setting),
3595 (ampersand) means the invoking user's
3605 expands to the same value as
3607 but the file is handled as a primary system mailbox by, e.g., the
3611 commands, meaning that messages that have been read in the current
3612 session will be moved to the
3614 mailbox instead of simply being flagged as read.
3617 If the name matches one of the strings defined with the command
3619 it is replaced by its long form and expanded.
3620 If the name ends with
3625 it is treated as being compressed with
3630 respectively, and transparently handled through an intermediate
3631 (un)compression step (using a temporary file) with the according
3632 facility, sufficient support provided.
3633 Likewise, if the named file doesn't exist, but a file with one of the
3634 mentioned compression extensions does, then the name is automatically
3635 expanded and the compressed file is used.
3637 Otherwise, if the name ends with an extension for which
3638 .Va file-hook-load-EXTENSION
3640 .Va file-hook-save-EXTENSION
3641 variables are set, then the given hooks will be used to load and save
3643 and \*(UA will work with an intermediate temporary file.
3645 MBOX files (flat file-based mailboxes) are generally locked during file
3646 operations in order to avoid inconsistencies due to concurrent
3648 \*(OPal Mailbox files which \*(UA treats as system
3650 boxes or primary mailboxes will also be protected by so-called dotlock
3651 files, the traditional way of mail spool file locking: for any file
3655 will be created for the duration of the synchronization \(em
3656 as necessary a privilege-separated dotlock child process will be used
3657 to accommodate for necessary privilege adjustments in order to create
3658 the dotlock file in the same directory
3659 and with the same user and group identities as the file of interest.
3662 for fine-tuning the handling of MBOX files.
3666 refers to a directory with the subdirectories
3671 then it is treated as a folder in
3673 format; \*(ID the variable
3675 can be used to control the format of yet non-existent folders.
3678 .Dl \*(IN protocol://[user[:password]@]host[:port][/path]
3679 .Dl \*(OU protocol://[user@]host[:port][/path]
3681 is taken as an Internet mailbox specification.
3682 The \*(OPally supported protocols are
3686 (POP3 with SSL/TLS encrypted transport).
3689 part is valid only for IMAP; there it defaults to
3691 Also see the section
3692 .Sx "On URL syntax and credential lookup" .
3696 contains special characters, in particular
3700 they must be escaped in URL notation \(en the command
3702 can be used to show the necessary conversion.
3706 Takes a message list and marks the messages as
3708 ged for urgent/special attention.
3709 This mark has no technical meaning in the mail system;
3710 it just causes messages to be highlighted in the header summary,
3711 and makes them specially addressable.
3720 With no arguments, list the names of the folders in the folder directory.
3721 With an existing folder as an argument,
3722 lists the names of folders below the named folder.
3728 but saves the message in a file named after the local part of the first
3729 recipient's address (instead of in
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 responds to all recipients regardless of the
3749 .It Ic followupsender
3752 but responds to the sender only regardless of the
3768 (f) Takes a list of message specifications and displays a summary of
3769 their message headers, exactly as via
3771 An alias of this command is
3774 .Sx "Specifying messages" .
3780 but saves the message in a file named after the local part of the
3781 recipient's address (instead of in
3786 Takes a message and the address of a recipient
3787 and forwards the message to him.
3788 The text of the original message is included in the new one,
3789 with the value of the
3791 variable preceding it.
3796 commands specify which header fields are included in the new message.
3797 Only the first part of a multipart message is included unless the
3798 .Va forward-as-attachment
3802 is set recipient addresses will be stripped from comments, names etc.
3806 Specifies which header fields are to be ignored with the command
3808 This command has no effect when the
3809 .Va forward-as-attachment
3814 Specifies which header fields are to be retained with the command
3819 This command has no effect when the
3820 .Va forward-as-attachment
3825 Define or list command aliases, so-called ghosts.
3826 Without arguments a list of all currently known aliases is shown.
3827 With one argument the expansion of the given alias is shown.
3828 With two or more arguments a command alias is defined or updated: the
3829 first argument is the name under which the remaining command line should
3830 be accessible, the content of which can be just about anything.
3831 A ghost can be used everywhere a normal command can be used, but always
3832 takes precedence; any arguments that are given to the command alias are
3833 joined onto the alias content, and the resulting string forms the
3834 command line that is, in effect, executed.
3837 .Bd -literal -offset indent
3839 `ghost': no such alias: "xx"
3842 ghost xx "echo hello,"
3851 (h) Show the current group of headers, the size of which depends on
3854 and the style of which can be adjusted with the variable
3856 If a message-specification is given the group of headers containing the
3857 first message therein is shown and the message at the top of the screen
3872 the list of history entries;
3875 argument selects and shows the respective history entry \(en
3878 to accept it, and the history entry will become the new history top.
3879 The default mode if no arguments are given is
3886 Takes a message list and marks each message therein to be saved in the
3891 Does not override the
3894 \*(UA deviates from the POSIX standard with this command, because a
3896 command issued after
3898 will display the following message, not the current one.
3903 (i) Part of the nestable
3904 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3905 conditional execution construct \(em if the given condition is true then
3906 the encapsulated block is executed.
3907 POSIX only supports the (case-insensitive) conditions
3912 end, all remaining conditions are non-portable extensions; note that
3913 falsely specified conditions cause the execution of the entire
3914 conditional construct until the (matching) closing
3916 command to be suppressed.
3917 The syntax of the nestable
3919 conditional execution construct requires that each condition and syntax
3920 element is surrounded by whitespace.
3922 .Bd -literal -offset indent
3931 The (case-insensitive) condition
3933 erminal will evaluate to true if the standard input is a terminal, i.e.,
3934 in interactive sessions.
3935 Another condition can be any boolean value (see the section
3936 .Sx "INTERNAL VARIABLES"
3937 for textual boolean representations) to mark an enwrapped block as
3940 .Dq always execute .
3941 It is possible to check
3942 .Sx "INTERNAL VARIABLES"
3945 variables for existence or compare their expansion against a user given
3946 value or another variable by using the
3948 .Pf ( Dq variable next )
3949 conditional trigger character;
3950 a variable on the right hand side may be signalled using the same
3952 The variable names may be enclosed in a pair of matching braces.
3955 The available comparison operators are
3959 (less than or equal to),
3965 (greater than or equal to),
3969 (is substring of) and
3971 (is not substring of).
3972 The values of the left and right hand side are treated as strings and
3973 are compared 8-bit byte-wise, ignoring case according to the rules of
3974 the US-ASCII encoding (therefore, dependent on the active locale,
3975 possibly producing false results for strings in the locale encoding).
3976 Except for the substring checks the comparison will instead be performed
3977 arithmetically if both, the user given value as well as the variable
3978 content, can be parsed as numbers (integers).
3979 An unset variable is treated as the empty string.
3982 When the \*(OPal regular expression support is available, the additional
3988 They treat the right hand side as an extended regular expression that is
3989 matched case-insensitively and according to the active
3991 locale, meaning that strings in the locale encoding should be matched
3995 Conditions can be joined via AND-OR lists (where the AND operator is
3997 and the OR operator is
3999 which have equal precedence and will be evaluated with left
4000 associativity, thus using the same syntax that is known for the
4002 It is also possible to form groups of conditions and lists by enclosing
4003 them in pairs of brackets
4004 .Ql [\ \&.\&.\&.\ ] ,
4005 which may be interlocked within each other, and also be joined via
4009 The results of individual conditions and entire groups may be modified
4010 via unary operators: the unary operator
4012 will reverse the result.
4014 .Bd -literal -offset indent
4018 if $ttycharset == "UTF-8"
4019 echo *ttycharset* is set to UTF-8, case-insensitively
4023 echo These two variables are equal
4025 if $version-major >= 15
4026 echo Running a new version..
4027 if $features =@ +regex
4028 if $TERM =~ "^xterm\&.*"
4029 echo ..in an X terminal
4032 if [ [ true ] && [ [ ${debug} ] || [ $verbose ] ] ]
4035 if true && $debug || ${verbose}
4036 echo Left associativity, as is known from the shell
4038 if ! ! true && ! [ ! $debug && ! $verbose ]
4039 echo Unary operator support
4047 Without arguments the list of ignored header fields is shown,
4048 otherwise the given list of header fields is added to the ignore list:
4049 Header fields in the ignore list are not shown on the terminal when
4050 a message is displayed.
4051 To display a message in its entirety, use the commands
4062 Shows the names of all available commands, alphabetically sorted.
4063 If given any non-whitespace argument the list will be shown in the order
4064 in which command prefixes are searched.
4067 output is available.
4071 This command can be used to localize changes to variables, meaning that
4072 their state will be reverted to the former one once the covered scope
4074 It can only be used inside of macro definition blocks introduced by
4078 and is interpreted as a boolean (string, see
4079 .Sx "INTERNAL VARIABLES" ) ;
4082 of an account is left once it is switched off again.
4083 .Bd -literal -offset indent
4084 define temporary_settings {
4099 enables change localization and calls
4101 which explicitly resets localization, then any value changes within
4103 will still be reverted by
4105 \*(ID Once the outermost level, the one which enabled localization
4106 first, is left, but no earlier, all adjustments will be unrolled.
4110 Reply to messages that come in via known
4113 .Pf ( Ic mlsubscribe )
4114 mailing lists, or pretend to do so (see
4115 .Sx "Mailing lists" ) :
4118 functionality this will actively resort and even remove message
4119 recipients in order to generate a message that is supposed to be sent to
4121 For example it will also implicitly generate a
4122 .Ql Mail-Followup-To:
4123 header if that seems useful, regardless of the setting of the variable
4130 but saves the message in a file named after the local part of the first
4131 recipient's address (instead of in
4136 (m) Takes a (list of) recipient address(es) as (an) argument(s),
4137 or asks on standard input if none were given;
4138 then collects the remaining mail content and sends it out.
4142 (mb) The given message list is to be sent to
4144 when \*(UA is quit; this is the default action unless the
4147 \*(ID This command can only be used in a primary system mailbox (see
4152 Without any arguments the content of the MIME type cache will displayed.
4153 Otherwise each argument defines a complete MIME type specification of
4154 a type that shall be added (prepended) to the cache.
4155 In any event MIME type sources are loaded first as necessary \(en
4156 .Va mimetypes-load-control
4157 can be used to fine-tune which sources are actually loaded.
4158 Refer to the section on
4159 .Sx "The mime.types files"
4160 for more on MIME type specifications and this topic in general.
4161 MIME type unregistration and cache resets can be triggered with
4166 Without arguments the list of all currently defined mailing lists
4167 (and their attributes, if any) is shown; a more verbose listing will be
4168 produced if either of
4173 Otherwise all given arguments (which need not be quoted except for
4174 whitespace) will be added and henceforth be recognized as mailing lists.
4175 Mailing lists may be removed via the command
4178 If the \*(OPal regular expression support is available then mailing
4179 lists may also be specified as (extended) regular expressions (see
4185 Without arguments the list of all currently defined mailing lists which
4186 have a subscription attribute is shown; a more verbose listing will be
4187 produced if either of
4192 Otherwise this attribute will be set for all given mailing lists,
4193 newly creating them as necessary (as via
4195 Subscription attributes may be removed via the command
4204 but moves the messages to a file named after the local part of the
4205 sender address of the first message (instead of in
4212 but marks the messages for deletion if they were transferred
4219 but also displays ignored header fields and all MIME parts.
4227 on the given messages, even in non-interactive mode and as long as the
4228 standard output is a terminal.
4234 \*(OP When used without arguments or if
4236 has been given the content of the
4238 cache is shown, loading it first as necessary.
4241 then the cache will only be initialized and
4243 will remove its contents.
4244 Note that \*(UA will try to load the file only once, use
4245 .Ql Ic \&\&netrc Ns \:\0\:clear
4246 to unlock further attempts.
4251 .Sx "On URL syntax and credential lookup" ;
4253 .Sx "The .netrc file"
4254 documents the file format in detail.
4258 Checks for new mail in the current folder without committing any changes
4260 If new mail is present, a message is shown.
4264 the headers of each new message are also shown.
4265 This command is not available for all mailbox types.
4273 Goes to the next message in sequence and types it.
4274 With an argument list, types the next matching message.
4288 If the current folder is accessed via a network connection, a
4290 command is sent, otherwise no operation is performed.
4296 but also displays ignored header fields and all MIME parts.
4304 on the given messages, even in non-interactive mode and as long as the
4305 standard output is a terminal.
4313 but also pipes ignored header fields and all parts of MIME
4314 .Ql multipart/alternative
4319 (pi) Takes a message list and a shell command
4320 and pipes the messages through the command.
4321 Without an argument the current message is piped through the command
4328 every message is followed by a formfeed character.
4349 (q) Terminates the session, saving all undeleted, unsaved messages in
4352 preserving all messages marked with
4356 or never referenced in the system
4358 box, and removing all other messages from the primary system mailbox.
4359 If new mail has arrived during the session,
4361 .Dq You have new mail
4363 If given while editing a mailbox file with the command line flag
4365 then the edit file is rewritten.
4366 A return to the shell is effected,
4367 unless the rewrite of edit file fails,
4368 in which case the user can escape with the exit command.
4382 Removes the named files or directories.
4383 If a name refer to a mailbox, e.g., a Maildir mailbox, then a mailbox
4384 type specific removal will be performed, deleting the complete mailbox.
4385 The user is asked for confirmation in interactive mode.
4389 Takes the name of an existing folder
4390 and the name for the new folder
4391 and renames the first to the second one.
4392 Both folders must be of the same type.
4396 (R) Reply to originator.
4397 Does not reply to other recipients of the original message.
4399 will exchange this command with
4403 is set the recipient address will be stripped from comments, names etc.
4407 (r) Take a message and group-responds to it by addressing the sender
4410 .Va followup-to-honour ,
4413 .Va recipients-in-cc
4414 influence response behaviour.
4417 offers special support for replying to mailing lists.
4420 is set recipient addresses will be stripped from comments, names etc.
4433 but initiates a group-reply regardless of the value of
4440 but responds to the sender only regardless of the value of
4447 but does not add any header lines.
4448 This is not a way to hide the sender's identity,
4449 but useful for sending a message again to the same recipients.
4453 Takes a list of messages and a user name
4454 and sends each message to the named user.
4456 and related header fields are prepended to the new copy of the message.
4474 .It Ic respondsender
4480 (ret) Without arguments the list of retained header fields is shown,
4481 otherwise the given list of header fields is added to the retain list:
4482 Header fields in the retain list are shown on the terminal when
4483 a message is displayed, all other header fields are suppressed.
4484 To display a message in its entirety, use the commands
4493 takes precedence over the mentioned.
4499 but saves the messages in a file named after the local part of the
4500 sender of the first message instead of (in
4502 and) taking a filename argument.
4506 (s) Takes a message list and a filename and appends each message in turn
4507 to the end of the file.
4508 If no filename is given, the
4511 The filename in quotes, followed by the generated character count
4512 is echoed on the user's terminal.
4513 If editing a primary system mailbox the messages are marked for deletion.
4514 Filename interpretation as described for the
4516 command is performed.
4533 Header fields thus marked are filtered out when saving a message by
4535 or when automatically saving to
4537 This command should only be applied to header fields that do not contain
4538 information needed to decode the message,
4539 as MIME content fields do.
4551 Header fields thus marked are the only ones saved with a message when
4554 or when automatically saving to
4559 The use of this command is strongly discouraged since it may strip
4560 header fields that are needed to decode the message correctly.
4564 Takes a message specification (list) and displays a header summary of
4565 all matching messages, as via
4567 This command is an alias of
4570 .Sx "Specifying messages" .
4574 Takes a message list and marks all messages as having been read.
4578 (se) Without arguments this command shows all internal variables which
4579 are currently known to \*(UA (they have been set).
4580 A more verbose listing will be produced if either of
4584 are set, in which case variables may be preceded with a comment line
4585 that gives some context of what \*(UA knows about the given variable.
4587 Otherwise the given variables (and arguments) are set or adjusted.
4588 Arguments are of the form
4590 (no space before or after
4594 if there is no value, i.e., a boolean variable.
4595 Quotation marks may be placed around any part of the assignment
4596 statement to quote blanks or tabs, e.g.,
4598 .Dl set indentprefix='->'
4600 If an argument begins with
4604 the effect is the same as invoking the
4606 command with the remaining part of the variable
4607 .Pf ( Ql unset save ) .
4611 that is known to map to an environment variable will automatically cause
4612 updates in the program environment (unsetting a variable in the
4613 environment requires corresponding system support).
4614 Please use the command
4616 for further environmental control.
4621 .Sx "INTERNAL VARIABLES"
4627 (sh) Invokes an interactive version of the shell.
4631 Without arguments the list of all currently defined shortcuts is
4633 Otherwise all given arguments (which need not be quoted except for
4634 whitespace) are treated as pairs of shortcuts and their expansions,
4635 creating new or changing already existing shortcuts, as necessary.
4636 Shortcuts may be removed via the command
4638 The expansion strings should be in the syntax that has been described
4647 but performs neither MIME decoding nor decryption, so that the raw
4648 message text is shown.
4652 (si) Shows the size in characters of each message of the given
4657 Shows the current sorting criterion when used without an argument.
4658 Otherwise creates a sorted representation of the current folder,
4661 command and the addressing modes such that they refer to messages in
4663 Message numbers are the same as in regular mode.
4667 a header summary in the new order is also displayed.
4668 Automatic folder sorting can be enabled by setting the
4670 variable, as in, e.g.,
4671 .Ql set autosort=thread .
4672 Possible sorting criterions are:
4674 .Bl -tag -compact -offset indent -width "subject"
4676 Sort the messages by their
4678 field, that is by the time they were sent.
4680 Sort messages by the value of their
4682 field, that is by the address of the sender.
4685 variable is set, the sender's real name (if any) is used.
4687 Sort the messages by their size.
4689 \*(OP Sort the message by their spam score, as has been classified by
4692 Sort the messages by their message status.
4694 Sort the messages by their subject.
4696 Create a threaded display.
4698 Sort messages by the value of their
4700 field, that is by the address of the recipient.
4703 variable is set, the recipient's real name (if any) is used.
4708 (so) The source command reads commands from the given file, which is
4709 subject to the usual filename expansions (see introductional words of
4711 If the given argument ends with a vertical bar
4713 then the argument will instead be interpreted as a shell command and
4714 \*(UA will read the output generated by it.
4717 cannot be used from within macros that execute as
4718 .Va folder-hook Ns s
4721 i.e., it can only be called from macros that were
4728 (beside not supporting pipe syntax aka shell command input) is that
4729 this command will not generate an error if the given file argument
4730 cannot be opened successfully.
4731 This can matter in, e.g., resource files, since loading of those is
4732 stopped when an error is encountered.
4736 \*(OP Takes a list of messages and clears their
4742 \*(OP Takes a list of messages and causes the
4744 to forget it has ever used them to train its Bayesian filter.
4745 Unless otherwise noted the
4747 flag of the message is inspected to chose whether a message shall be
4755 \*(OP Takes a list of messages and informs the Bayesian filter of the
4759 This also clears the
4761 flag of the messages in question.
4765 \*(OP Takes a list of messages and rates them using the configured
4766 .Va spam-interface ,
4767 without modifying the messages, but setting their
4769 flag as appropriate; because the spam rating headers are lost the rate
4770 will be forgotten once the mailbox is left.
4771 Refer to the manual section
4773 for the complete picture of spam handling in \*(UA.
4777 \*(OP Takes a list of messages and sets their
4783 \*(OP Takes a list of messages and informs the Bayesian filter of the
4789 flag of the messages in question.
4798 Create a threaded representation of the current folder,
4799 i.\|e. indent messages that are replies to other messages in the header
4800 display and change the
4802 command and the addressing modes such that they refer to messages in the
4804 Message numbers are the same as in unthreaded mode.
4808 a header summary in threaded order is also displayed.
4822 (to) Takes a message list and types out the first
4824 lines of each message on the users' terminal.
4825 The only header fields that are displayed are
4832 will instead honour configured lists).
4833 It is possible to apply compression to what is displayed by setting
4835 Messages are decrypted and converted to the terminal character set
4840 (tou) Takes a message list and marks the messages for saving in
4842 \*(UA deviates from the POSIX standard with this command,
4845 command will display the following message instead of the current one.
4851 but also displays out ignored header fields and all parts of MIME
4852 .Ql multipart/alternative
4857 (t) Takes a message list and types out each message on the users'
4863 For MIME multipart messages, all parts with a content type of
4867 are shown, the other are hidden except for their headers.
4868 Messages are decrypted and converted to the terminal character set
4873 Delete all given accounts.
4874 An error message is shown if a given account is not defined.
4877 will discard all existing accounts.
4881 (una) Takes a list of names defined by alias commands
4882 and discards the remembered groups of users.
4885 will discard all existing aliases.
4889 Takes a message list and marks each message as not having been answered.
4895 ing, specified by its context and input sequence, both of which may be
4896 specified as a wildcard (asterisk,
4900 will remove all bindings of all contexts.
4904 Only applicable to threaded mode.
4905 Takes a message list and makes the message and all replies to it visible
4906 in header summaries again.
4907 When a message becomes the current message,
4908 it is automatically made visible.
4909 Also when a message with collapsed replies is displayed,
4910 all of these are automatically uncollapsed.
4916 mapping for the given colour type (see
4918 for a list of types) and mapping; if the optional precondition argument
4919 is used then only the exact tuple of mapping and precondition is removed.
4922 will remove all mappings (no precondition allowed).
4924 .Sx "Coloured display"
4925 for the general picture.
4929 Deletes the custom headers given as arguments.
4932 will remove all custom headers.
4936 Undefine all given macros.
4937 An error message is shown if a given macro is not defined.
4940 will discard all existing macros.
4944 (u) Takes a message list and marks each message as not being deleted.
4948 Takes a message list and
4954 Takes a message list and marks each message as not being
4959 Removes the header field names from the list of ignored fields for the
4964 will remove all fields.
4968 Removes the header field names from the list of retained fields for the
4973 will remove all fields.
4977 Remove all the given command
4981 will remove all ghosts.
4985 Removes the header field names from the list of ignored fields.
4988 will remove all fields.
4992 Delete all given MIME types, e.g.,
4993 .Ql unmimetype text/plain
4994 will remove all registered specifications for the MIME type
4998 will discard all existing MIME types, just as will
5000 but which also reenables cache initialization via
5001 .Va mimetypes-load-control .
5005 Forget about all the given mailing lists.
5008 will remove all lists.
5013 .It Ic unmlsubscribe
5014 Remove the subscription attribute from all given mailing lists.
5017 will clear the attribute from all lists which have it set.
5028 Takes a message list and marks each message as not having been read.
5032 Removes the header field names from the list of retained fields.
5035 will remove all fields.
5039 Removes the header field names from the list of ignored fields for
5043 will remove all fields.
5047 Removes the header field names from the list of retained fields for
5051 will remove all fields.
5055 (uns) Takes a list of internal variable names and discards their
5056 remembered values; the reverse of
5063 Deletes the shortcut names given as arguments.
5066 will remove all shortcuts.
5070 Disable sorted or threaded mode
5076 return to normal message order and,
5080 displays a header summary.
5090 Decode the given URL-encoded string arguments and show the results.
5091 Note the resulting strings may not be valid in the current locale, see
5096 URL-encode the given arguments and show the results.
5097 Because the arguments effectively are in the character set of the
5098 current locale the results will vary accordingly unless the input solely
5099 consists of characters in the portable character set, see
5100 .Sx "Character sets" .
5104 Edit the values of or create the given variable(s) in the
5106 Boolean variables cannot be edited.
5110 This command produces the same output as the listing mode of
5114 ity adjustments, but only for the given variables.
5118 \*(OP Takes a message list and verifies each message.
5119 If a message is not a S/MIME signed message,
5120 verification will fail for it.
5121 The verification process checks if the message was signed using a valid
5123 if the message sender's email address matches one of those contained
5124 within the certificate,
5125 and if the message content has been altered.
5129 (v) Takes a message list and invokes the display editor on each message.
5130 Modified contents are discarded unless the
5136 (w) For conventional messages the body without all headers is written.
5137 The output is decrypted and converted to its native format as necessary.
5138 If the output file exists, the text is appended.
5139 If a message is in MIME multipart format its first part is written to
5140 the specified file as for conventional messages,
5141 and the user is asked for a filename to save each other part.
5142 For convience saving of each part may be skipped by giving an empty value;
5143 the same result can also be achieved by writing it to
5145 For the second and subsequent parts a leading
5147 character causes the part to be piped to the remainder of the user input
5148 interpreted as a shell command;
5149 otherwise the user input is expanded as usually for folders,
5150 e.g., tilde expansion is performed.
5151 In non-interactive mode, only the parts of the multipart message
5152 that have a filename given in the part header are written,
5153 the others are discarded.
5154 The original message is never marked for deletion in the originating
5157 the contents of the destination file are overwritten if the file
5159 No special handling of compressed files is performed.
5168 \*(UA presents message headers in windowfuls as described under the
5171 This command scrolls to the next window of messages.
5172 If an argument is given, it specifies the window to use.
5173 A number prefixed by
5177 indicates that the window is calculated in relation to the current position.
5178 A number without a prefix specifies an absolute window number,
5181 lets \*(UA scroll to the last window of messages.
5187 but scrolls to the next or previous window that contains at least one
5196 .\" .Sh TILDE ESCAPES {{{
5199 Here is a summary of the tilde escapes,
5200 which are used to perform special functions when composing messages.
5201 Tilde escapes are only recognized at the beginning of lines.
5204 is somewhat of a misnomer since the actual escape character can be
5205 changed by adjusting the option
5208 .Bl -tag -width ".Ic __ filename"
5211 Insert the string of text in the message prefaced by a single
5213 (If the escape character has been changed,
5214 that character must be doubled
5215 in order to send it at the beginning of a line.)
5218 .It Ic ~! Ar command
5219 Execute the indicated shell
5221 then return to the message.
5225 Same effect as typing the end-of-file character.
5228 .It Ic ~: Ar \*(UA-command Ns \0or Ic ~_ Ar \*(UA-command
5229 Execute the given \*(UA command.
5230 Not all commands, however, are allowed.
5234 Write a summary of command escapes.
5237 .It Ic ~< Ar filename
5242 .It Ic ~<! Ar command
5244 is executed using the shell.
5245 Its standard output is inserted into the message.
5248 .It Ic ~@ Op Ar filename...
5249 With no arguments, edit the attachment list interactively.
5250 If an attachment's file name is left empty,
5251 that attachment is deleted from the list.
5252 When the end of the attachment list is reached,
5253 \*(UA will ask for further attachments until an empty name is given.
5254 If a given file name solely consists of the number sign
5256 followed by a valid message number of the currently active mailbox, then
5257 the given message is attached as a MIME
5259 and the rest of this section does not apply.
5261 If character set conversion has been compiled into \*(UA, then this mode
5262 gives the user the option to specify input and output character sets,
5263 unless the file extension indicates binary content, in which case \*(UA
5264 asks whether this step shall be skipped for the attachment in question.
5265 If not skipped, then the charset that succeeds to represent the
5266 attachment data will be used in the
5268 MIME parameter of the mail message:
5270 .Bl -bullet -compact
5272 If input and output character sets are specified, then the conversion is
5273 performed on the fly.
5274 The user will be asked repeatedly until the desired conversion succeeds.
5276 If only an output character set is specified, then the input is assumed
5279 charset and will be converted to the given output charset on the fly.
5280 The user will be asked repeatedly until the desired conversion succeeds.
5282 If no character sets are specified at all then the algorithm that is
5283 documented in the section
5284 .Sx "Character sets"
5285 is applied, but directly and on the fly.
5286 The user will be asked repeatedly until the desired conversion succeeds.
5288 Finally, if an input-, but no output character set is specified, then no
5289 conversion is ever performed, but the
5291 MIME parameter value will still be set to the user input.
5293 The character set selection loop can be left by typing
5295 i.e., causing an interrupt.
5296 .\" \*(OU next sentence
5297 Note that before \*(UA version 15.0 this terminates the entire
5298 current attachment selection, not only the character set selection.
5301 Without character set conversion support, \*(UA will ask for the input
5302 character set only, and it'll set the
5304 MIME parameter value to the given input, if any;
5305 if no user input is seen then the
5307 character set will be used for the parameter value instead.
5308 Note that the file extension check isn't performed in this mode, since
5309 no conversion will take place anyway.
5311 Note that in non-interactive mode, for reproduceabilities sake, there
5312 will always be two questions for each attachment, regardless of whether
5313 character set conversion is available and what the file extension is.
5314 The first asks for the filename, and the second asks for the input
5315 character set to be passed through to the corresponding MIME parameter;
5316 no conversion will be tried if there is input to the latter question,
5317 otherwise the usual conversion algorithm, as above, is applied.
5318 For message attachments, the answer to the second question is completely
5323 arguments are specified for the
5325 command they are treated as a file list of
5327 -style quoted arguments, optionally also separated by commas, which are
5328 expanded and then appended to the existing list of message attachments.
5329 Message attachments can only be added via the first method.
5330 In this mode the (text) attachments are assumed to be in
5332 encoding, and will be evaluated as documented in the section
5333 .Sx "Character sets" .
5337 Inserts the string contained in the
5340 .Ql Ic ~i Ns \0Sign ) .
5341 The escape sequences tabulator
5349 Inserts the string contained in the
5352 .Ql Ic ~i Ns \0sign ) .
5353 The escape sequences tabulator
5360 .It Ic ~b Ar name ...
5361 Add the given names to the list of blind carbon copy recipients.
5364 .It Ic ~c Ar name ...
5365 Add the given names to the list of carbon copy recipients.
5369 Read the file specified by the
5371 variable into the message.
5375 Invoke the text editor on the message collected so far.
5376 After the editing session is finished,
5377 the user may continue appending text to the message.
5380 .It Ic ~F Ar messages
5381 Read the named messages into the message being sent, including all
5382 message headers and MIME parts.
5383 If no messages are specified, read in the current message.
5386 .It Ic ~f Ar messages
5387 Read the named messages into the message being sent.
5388 If no messages are specified, read in the current message.
5392 lists are used to modify the message headers.
5393 For MIME multipart messages,
5394 only the first displayable part is included.
5398 Edit the message header fields
5403 by typing each one in turn and allowing the user to edit the field.
5404 The default values for these fields originate from the
5412 Edit the message header fields
5418 by typing each one in turn and allowing the user to edit the field.
5421 .It Ic ~i Ar variable
5422 Insert the value of the specified variable into the message,
5423 adding a newline character at the end.
5424 The message remains unaltered if the variable is unset or empty.
5425 The escape sequences tabulator
5432 .It Ic ~M Ar messages
5433 Read the named messages into the message being sent,
5436 If no messages are specified, read the current message.
5439 .It Ic ~m Ar messages
5440 Read the named messages into the message being sent,
5443 If no messages are specified, read the current message.
5447 lists are used to modify the message headers.
5448 For MIME multipart messages,
5449 only the first displayable part is included.
5453 Display the message collected so far,
5454 prefaced by the message header fields
5455 and followed by the attachment list, if any.
5459 Abort the message being sent,
5460 copying it to the file specified by the
5467 .It Ic ~R Ar filename
5468 Read the named file into the message, indented by
5472 .It Ic ~r Ar filename
5473 Read the named file into the message.
5477 Cause the named string to become the current subject field.
5480 .It Ic ~t Ar name ...
5481 Add the given name(s) to the direct recipient list.
5484 .It Ic ~U Ar messages
5485 Read in the given / current message(s) excluding all headers, indented by
5489 .It Ic ~u Ar messages
5490 Read in the given / current message(s), excluding all headers.
5494 Invoke an alternate editor (defined by the
5496 option) on the message collected so far.
5497 Usually, the alternate editor will be a screen editor.
5498 After the editor is quit,
5499 the user may resume appending text to the end of the message.
5502 .It Ic ~w Ar filename
5503 Write the message onto the named file.
5505 the message is appended to it.
5511 except that the message is not saved at all.
5514 .It Ic ~| Ar command
5515 Pipe the message through the specified filter command.
5516 If the command gives no output or terminates abnormally,
5517 retain the original text of the message.
5520 is often used as a rejustifying filter.
5525 .\" .Sh INTERNAL VARIABLES {{{
5526 .Sh "INTERNAL VARIABLES"
5528 Internal \*(UA variables are controlled via the
5532 commands; prefixing a variable name with the string
5536 has the same effect as using
5542 Creation or editing of variables can be performed in the
5547 will give more insight on the given variable(s), and
5549 when called without arguments, will show a listing of all variables.
5550 Some well-known variables will also become inherited from the
5553 implicitly, others can be explicitly imported with the command
5555 and henceforth share the said properties.
5558 Two different kind of internal variables exist.
5559 There are boolean variables, which can only be in one of the two states
5563 and value variables with a(n optional) string value.
5564 For the latter proper quoting is necessary upon assignment time, the
5565 introduction of the section
5567 documents the supported quoting rules.
5569 .Bd -literal -offset indent
5570 wysh set one=val\e 1 two="val 2" \e
5571 three='val "3"' four=$'val \e'4\e''
5572 varshow one two three four
5573 unset one two three four
5577 Dependent upon the actual option the string values will be interpreted
5578 as numbers, colour names, normal text etc., but there also exists
5579 a special kind of string value, the
5580 .Dq boolean string ,
5581 which must either be a decimal integer (in which case
5585 and any other value is true) or any of the (case-insensitive) strings
5591 for a false boolean and
5597 for a true boolean; a special kind of boolean string is the
5599 which is a boolean string that can optionally be prefixed with the
5600 (case-insensitive) term
5604 which causes prompting of the user in interactive mode, with the given
5605 boolean as the default value.
5607 .\" .Ss "Initial settings" {{{
5608 .\" (Keep in SYNC: ./nail.h:okeys, ./nail.rc, ./nail.1:"Initial settings")
5609 .Ss "Initial Settings"
5611 The standard POSIX 2008/Cor 1-2013 mandates the following initial
5617 .Pf no Va autoprint ,
5631 .Pf no Va ignoreeof ,
5633 .Pf no Va keepsave ,
5635 .Pf no Va outfolder ,
5640 (note that \*(UA deviates from the standard by using
5644 special prompt escape results in
5652 .Pf no Va sendwait ,
5661 Notes: \*(UA doesn't support the
5663 variable \(en use command line options or
5665 to pass options through to a
5667 And the default global
5669 file (which is loaded unless the
5671 command line flag has been used or the
5672 .Ev NAIL_NO_SYSTEM_RC
5673 environment variable is set) bends those initial settings a bit, e.g.,
5674 it sets the variables
5679 to name a few, calls
5681 etc., and should thus be taken into account.
5684 .\" .Ss "Variables" {{{
5687 .Bl -tag -width ".It Va _utoprin_"
5689 .It Va add-file-recipients
5690 \*(BO When file or pipe recipients have been specified,
5691 mention them in the corresponding address fields of the message instead
5692 of silently stripping them from their recipient list.
5693 By default such addressees are not mentioned.
5697 \*(BO Causes only the local part to be evaluated
5698 when comparing addresses.
5702 \*(BO Causes messages saved in
5704 to be appended to the end rather than prepended.
5705 This should always be set.
5709 \*(BO Causes \*(UA to prompt for the subject of each message sent.
5710 If the user responds with simply a newline,
5711 no subject field will be sent.
5715 \*(BO Causes the prompts for
5719 lists to appear after the message has been edited.
5723 \*(BO If set, \*(UA asks for files to attach at the end of each message,
5724 shall the list be found empty at that time.
5725 An empty line finalizes the list.
5729 \*(BO Causes the user to be prompted for carbon copy recipients
5730 (at the end of each message if
5734 are set) shall the list be found empty (at that time).
5735 An empty line finalizes the list.
5739 \*(BO Causes the user to be prompted for blind carbon copy
5740 recipients (at the end of each message if
5744 are set) shall the list be found empty (at that time).
5745 An empty line finalizes the list.
5749 \*(BO\*(OP Causes the user to be prompted if the message is to be
5750 signed at the end of each message.
5753 variable is ignored when this variable is set.
5757 \*(BO Alternative name for
5764 .It Va attachment-ask-content-description , \
5765 attachment-ask-content-disposition , \
5766 attachment-ask-content-id , \
5767 attachment-ask-content-type
5768 \*(BO If set then the user will be prompted for some attachment
5769 information when editing the attachment list.
5770 It is advisable to not use these but for the first of the variables;
5771 even for that it has to be noted that the data is used
5777 A sequence of characters to display in the
5781 as shown in the display of
5783 each for one type of messages (see
5784 .Sx "Message states" ) ,
5785 with the default being
5788 .Ql NU\ \ *HMFAT+\-$~
5791 variable is set, in the following order:
5793 .Bl -tag -compact -offset indent -width ".It Ql _"
5815 start of a collapsed thread.
5817 an uncollapsed thread (TODO ignored for now).
5821 classified as possible spam.
5827 Specifies a list of recipients to which a blind carbon copy of each
5828 outgoing message will be sent automatically.
5832 Specifies a list of recipients to which a carbon copy of each outgoing
5833 message will be sent automatically.
5837 \*(BO Causes threads to be collapsed automatically when threaded mode
5844 \*(BO Causes the delete command to behave like
5846 thus, after deleting a message the next one will be typed automatically.
5850 \*(BO\*(OB Causes threaded mode (see the
5852 command) to be entered automatically when a folder is opened.
5854 .Ql autosort=thread .
5858 Causes sorted mode (see the
5860 command) to be entered automatically with the value of this option as
5861 sorting method when a folder is opened, e.g.,
5862 .Ql set autosort=thread .
5866 \*(BO Enables the substitution of
5868 by the contents of the last command line in shell escapes.
5871 .It Va batch-exit-on-error
5872 \*(BO If the batch mode has been enabled via the
5874 command line option, then this variable will be consulted whenever \*(UA
5875 completes one operation (returns to the command prompt); if it is set
5876 then \*(UA will terminate if the last operation generated an error.
5880 \*(OP Terminals generate multi-byte sequences for certain forms of
5881 input, for example for function and other special keys.
5882 Some terminals however do not write these multi-byte sequences as
5883 a whole, but byte-by-byte, and the latter is what \*(UA actually reads.
5884 This variable specifies the timeout in milliseconds that the MLE (see
5885 .Sx "On terminal control and line editor" )
5886 waits for more bytes to arrive unless it considers a sequence
5892 \*(BO Causes automatic display of a header summary after executing a
5894 command, and thus complements the standard variable
5896 which controls header summary display on program startup.
5897 It is only meaningful if
5903 \*(BO Sets some cosmetical features to traditional BSD style;
5904 has the same affect as setting
5906 and all other variables prefixed with
5908 it also changes the meaning of the \*(UA specific
5911 escape sequence and changes behaviour of
5913 (which doesn't exist in BSD).
5917 \*(BO Changes the letters shown in the first column of a header
5918 summary to traditional BSD style.
5922 \*(BO Changes the display of columns in a header summary to traditional
5927 \*(BO Changes some informational messages to traditional BSD style.
5933 field to appear immediately after the
5935 field in message headers and with the
5937 .Sx "TILDE ESCAPES" .
5941 The value that should appear in the
5945 MIME header fields when no character set conversion of the message data
5947 This defaults to US-ASCII, and the chosen character set should be
5948 US-ASCII compatible.
5952 \*(OP The default 8-bit character set that is used as an implicit last
5953 member of the variable
5955 This defaults to UTF-8.
5956 If no character set conversion capabilities are available in \*(UA then
5957 the only supported character set is
5959 Refer to the section
5960 .Sx "Character sets"
5961 for the complete picture of character set conversion in \*(UA.
5964 .It Va charset-unknown-8bit
5965 \*(OP RFC 1428 specifies conditions when internet mail gateways shall
5967 the content of a mail message by using a character set with the name
5969 Because of the unclassified nature of this character set \*(UA will not
5970 be capable to convert this character set to any other character set.
5971 If this variable is set any message part which uses the character set
5973 is assumed to really be in the character set given in the value,
5974 otherwise the (final) value of
5976 is used for this purpose.
5978 This variable will also be taken into account if a MIME type (see
5979 .Sx "The mime.types files" )
5980 of a MIME message part that uses the
5982 character set is forcefully treated as text.
5986 The default value for the
5991 .It Va colour-disable
5992 \*(BO\*(OP Forcefully disable usage of colours.
5993 Also see the section
5994 .Sx "Coloured display" .
5998 \*(BO\*(OP Whether colour shall be used for output that is paged through
6000 Note that pagers may need special flags, e.g.,
6008 in order to support colours.
6009 Often doing manual adjustments is unnecessary since \*(UA may perform
6010 adjustments dependend on the value of the environment variable
6012 (see there for more).
6016 In a(n interactive) terminal session, then if this valued option is set
6017 it'll be used as a threshold to determine how many lines the given
6018 output has to span before it will be displayed via the configured
6022 can be forced by setting this to the value
6024 setting it without a value will deduce the current height of the
6025 terminal screen to compute the treshold (see
6033 \*(OB A variable counterpart of the
6035 command (see there for documentation), interpreted as a comma-separated
6036 list of custom headers to be injected, to include commas in the header
6037 bodies escape them with reverse solidus, e.g.:
6039 .Dl set customhdr='Hdr1: Body1-1\e, Body1-2, Hdr2: Body2'
6045 the message date, if any is to be displayed according to the format of
6047 is by default taken from the
6049 line of the message.
6050 If this variable is set the date as given in the
6052 header field is used instead, converted to local time.
6053 To control the display format of the date assign a valid
6058 format should not be used, because \*(UA doesn't take embedded newlines
6059 into account when calculating how many lines fit onto the screen.)
6061 .Va datefield-markout-older .
6064 .It Va datefield-markout-older
6065 This option, when set in addition to
6069 messages (concept is rather comparable to the
6071 option of the POSIX utility
6073 The content interpretation is identical to
6078 \*(BO Enables debug messages and obsoletion warnings, disables the
6079 actual delivery of messages and also implies
6085 .It Va disposition-notification-send
6087 .Ql Disposition-Notification-To:
6088 header (RFC 3798) with the message.
6092 .\" TODO .It Va disposition-notification-send-HOST
6094 .\".Va disposition-notification-send
6095 .\" for SMTP accounts on a specific host.
6096 .\" TODO .It Va disposition-notification-send-USER@HOST
6098 .\".Va disposition-notification-send
6099 .\"for a specific account.
6103 \*(BO When dot is set, a period
6105 on a line by itself during message input in (interactive) compose mode
6106 will be treated as end-of-message (in addition to the normal end-of-file
6115 .It Va dotlock-ignore-error
6116 \*(BO\*(OP Synchronization of mailboxes which \*(UA treats as system
6117 mailboxes (see the command
6119 will be protected with so-called dotlock files\(emthe traditional mail
6120 spool file locking method\(emin addition to system file locking.
6121 Because \*(UA ships with a privilege-separated dotlock creation program
6122 that should always be able to create such a dotlock file there is no
6123 good reason to ignore dotlock file creation errors, and thus these are
6124 fatal unless this variable is set.
6128 \*(BO If this variable is set then the editor is started automatically
6129 when a message is composed in interactive mode, as if the
6135 variable is implied for this automatically spawned editor session.
6139 \*(BO When a message is edited while being composed,
6140 its header is included in the editable text.
6150 fields are accepted within the header, other fields are ignored.
6154 \*(BO When entering interactive mode \*(UA normally writes
6155 .Dq \&No mail for user
6156 and exits immediately if a mailbox is empty or doesn't exist.
6157 If this option is set \*(UA starts even with an empty or nonexistent
6158 mailbox (the latter behaviour furtherly depends upon
6164 Suggestion for the MIME encoding to use in outgoing text messages
6166 Valid values are the default
6167 .Ql quoted-printable ,
6172 may cause problems when transferring mail messages over channels that
6173 are not ESMTP (RFC 1869) compliant.
6174 If there is no need to encode a message,
6176 transfer mode is always used regardless of this variable.
6177 Binary data is always encoded as
6182 If defined, the first character of this option
6183 gives the character to use in place of
6186 .Sx "TILDE ESCAPES" .
6190 If not set then file and command pipeline targets are not allowed,
6191 and any such address will be filtered out, giving a warning message.
6192 If set without a value then all possible recipient address
6193 specifications will be accepted \(en see the section
6194 .Sx "On sending mail, and non-interactive mode"
6196 To accept them, but only in interactive mode, or when tilde commands
6197 were enabled explicitly by using one of the command line options
6201 set this to the (case-insensitive) value
6203 (note right now this is actually like setting
6204 .Ql restrict,-all,+name,+addr ) .
6206 In fact the value is interpreted as a comma-separated list of values.
6209 then the existence of disallowed specifications is treated as a hard
6210 send error instead of only filtering them out.
6211 The remaining values specify whether a specific type of recipient
6212 address specification is allowed (optionally indicated by a plus sign
6214 prefix) or disallowed (prefixed with a hyphen
6218 addresses all possible address specifications,
6222 command pipeline targets,
6224 plain user names and (MTA) aliases (\*(OB
6226 may be used as an alternative syntax to
6231 These kind of values are interpreted in the given order, so that
6232 .Ql restrict,\:fail,\:+file,\:-all,\:+addr
6233 will cause hard errors for any non-network address recipient address
6234 unless \*(UA is in interactive mode or has been started with the
6238 command line option; in the latter case(s) any address may be used, then.
6242 Unless this variable is set additional
6244 (Mail-Transfer-Agent)
6245 arguments from the command line, as can be given after a
6247 separator, are ignored due to safety reasons.
6248 However, if set to the special (case-insensitive) value
6250 then the presence of additional MTA arguments is treated as a hard
6251 error that causes \*(UA to exit with failure status.
6252 A lesser strict variant is the otherwise identical
6254 which does accept such arguments in interactive mode, or if tilde
6255 commands were enabled explicitly by using one of the command line options
6262 \*(RO Information on the features compiled into \*(UA \(en the content
6263 of this variable is identical to the output of the command
6268 \*(BO This option reverses the meanings of a set of reply commands,
6269 turning the lowercase variants, which by default address all recipients
6270 included in the header of a message
6271 .Pf ( Ic reply , respond , followup )
6272 into the uppercase variants, which by default address the sender only
6273 .Pf ( Ic Reply , Respond , Followup )
6276 .Ic replysender , respondsender , followupsender
6278 .Ic replyall , respondall , followupall
6279 are not affected by the current setting of
6284 .It Va file-hook-load-EXTENSION , file-hook-save-EXTENSION
6285 It is possible to install file hooks which will be used by the
6287 command in order to be able to transparently handle (through an
6288 intermediate temporary file) files with specific
6290 s: the variable values can include shell snippets and are expected to
6291 write data to standard output / read data from standard input,
6293 \*(ID The variables may not be changed while there is a mailbox
6295 .Bd -literal -offset indent
6296 set file-hook-load-xy='echo >&2 XY-LOAD; gzip -cd' \e
6297 file-hook-save-xy='echo >&2 XY-SAVE; gzip -c' \e
6298 record=+null-sent.xy
6303 The default path under which mailboxes are to be saved:
6304 file names that begin with the plus-sign
6306 will be expanded by prefixing them with the value of this variable.
6307 The same special syntax conventions as documented for the
6309 command may be used; if the non-empty value doesn't start with a solidus
6313 will be prefixed automatically.
6314 If unset or the empty string any
6316 prefixing file names will remain unexpanded.
6320 This variable can be set to the name of a
6322 macro which will be called whenever a
6325 The macro will also be invoked when new mail arrives,
6326 but message lists for commands executed from the macro
6327 only include newly arrived messages then.
6329 are activated by default in a folder hook, causing the covered settings
6330 to be reverted once the folder is left again.
6333 Macro behaviour, including option localization, will change in v15.
6334 Please be aware of that and possibly embed a version check in a resource
6338 .It Va folder-hook-FOLDER
6343 Unlike other folder specifications, the fully expanded name of a folder,
6344 without metacharacters, is used to avoid ambiguities.
6345 However, if the mailbox resides under
6349 specification is tried in addition, e.g., if
6353 (and thus relative to the user's home directory) then
6354 .Pa /home/usr1/mail/sent
6356 .Ql folder-hook-/home/usr1/mail/sent
6357 first, but then followed by
6358 .Ql folder-hook-+sent .
6362 \*(BO Controls whether a
6363 .Ql Mail-Followup-To:
6364 header is generated when sending messages to known mailing lists.
6366 .Va followup-to-honour
6368 .Ic mlist , mlsubscribe , reply
6373 .It Va followup-to-honour
6375 .Ql Mail-Followup-To:
6376 header is honoured when group-replying to a message via
6380 This is a quadoption; if set without a value it defaults to
6390 .It Va forward-as-attachment
6391 \*(BO Original messages are normally sent as inline text with the
6394 and only the first part of a multipart message is included.
6395 With this option messages are sent as unmodified MIME
6397 attachments with all of their parts included.
6401 The address (or a list of addresses) to put into the
6403 field of the message header, quoting RFC 5322:
6404 the author(s) of the message, that is, the mailbox(es) of the person(s)
6405 or system(s) responsible for the writing of the message.
6408 ing to messages these addresses are handled as if they were in the
6412 If the machine's hostname is not valid at the Internet (for example at
6413 a dialup machine) then either this variable or
6415 (\*(IN and with a defined SMTP protocol in
6418 adds even more fine-tuning capabilities),
6422 contains more than one address,
6425 variable is required (according to the standard RFC 5322).
6429 \*(BO When replying to or forwarding a message \*(UA normally removes
6430 the comment and name parts of email addresses.
6431 If this variable is set such stripping is not performed,
6432 and comments, names etc. are retained.
6436 The string to put before the text of a message with the
6440 .Va forward-as-attachment
6443 .Dq -------- Original Message --------
6444 if unset; No heading is put if it is set to the empty string.
6448 \*(BO Causes the header summary to be written at startup and after
6449 commands that affect the number of messages or the order of messages in
6450 the current folder; enabled by default.
6451 The command line option
6457 complements this and controls header summary display on folder changes.
6462 A format string to use for the summary of
6464 similar to the ones used for
6467 Format specifiers in the given string start with a percent character
6469 and may be followed by an optional decimal number indicating the field
6470 width \(em if that is negative, the field is to be left-aligned.
6471 Valid format specifiers are:
6474 .Bl -tag -compact -offset indent -width "_%%_"
6476 A plain percent character.
6479 a space character but for the current message
6481 for which it expands to
6485 a space character but for the current message
6487 for which it expands to
6490 \*(OP The spam score of the message, as has been classified via the
6493 Shows only a replacement character if there is no spam support.
6495 Message attribute character (status flag); the actual content can be
6499 The date when the message was received, or the date found in the
6503 variable is set (optionally to a date display format string).
6505 The indenting level in threaded mode.
6507 The address of the message sender.
6509 The message thread tree structure.
6510 (Note that this format doesn't support a field width.)
6512 The number of lines of the message, if available.
6516 The number of octets (bytes) in the message, if available.
6518 Message subject (if any).
6520 Message subject (if any) in double quotes.
6522 Message recipient flags: is the addressee of the message a known or
6523 subscribed mailing list \(en see
6528 The position in threaded/sorted order.
6532 .Ql %>\&%a\&%m\ %-18f\ %16d\ %4l/%\-5o\ %i%-s ,
6534 .Ql %>\&%a\&%m\ %20-f\ \ %16d\ %3l/%\-5o\ %i%-S
6545 .It Va headline-bidi
6546 Bidirectional text requires special treatment when displaying headers,
6547 because numbers (in dates or for file sizes etc.) will not affect the
6548 current text direction, in effect resulting in ugly line layouts when
6549 arabic or other right-to-left text is to be displayed.
6550 On the other hand only a minority of terminals is capable to correctly
6551 handle direction changes, so that user interaction is necessary for
6553 Note that extended host system support is required nonetheless, e.g.,
6554 detection of the terminal character set is one precondition;
6555 and this feature only works in an Unicode (i.e., UTF-8) locale.
6557 In general setting this variable will cause \*(UA to encapsulate text
6558 fields that may occur when displaying
6560 (and some other fields, like dynamic expansions in
6562 with special Unicode control sequences;
6563 it is possible to fine-tune the terminal support level by assigning
6565 no value (or any value other than
6570 will make \*(UA assume that the terminal is capable to properly deal
6571 with Unicode version 6.3, in which case text is embedded in a pair of
6572 U+2068 (FIRST STRONG ISOLATE) and U+2069 (POP DIRECTIONAL ISOLATE)
6574 In addition no space on the line is reserved for these characters.
6576 Weaker support is chosen by using the value
6578 (Unicode 6.3, but reserve the room of two spaces for writing the control
6579 sequences onto the line).
6584 select Unicode 1.1 support (U+200E, LEFT-TO-RIGHT MARK); the latter
6585 again reserves room for two spaces in addition.
6589 \*(OP If a line editor is available then this can be set to
6590 name the (expandable) path of the location of a permanent history file.
6593 .It Va history-gabby
6594 \*(BO\*(OP Add more entries to the history as is normally done.
6597 .It Va history-gabby-persist
6598 \*(BO\*(OP \*(UA's own MLE will not save the additional
6600 entries in persistent storage unless this variable is set.
6601 On the other hand it will not loose the knowledge of whether
6602 a persistent entry was gabby or not.
6608 \*(OP If a line editor is available this value restricts the
6609 amount of history entries that are saved into a set and valid
6611 A value of less than 0 disables this feature;
6612 note that loading and incorporation of
6614 upon program startup can also be suppressed by doing this.
6615 If unset or 0, a default value will be used.
6616 Dependent on the available line editor this will also define the
6617 number of history entries in memory;
6618 it is also editor-specific whether runtime updates of this value will
6623 \*(BO This option is used to hold messages in the system
6625 box, and it is set by default.
6629 Use this string as hostname when expanding local addresses instead of
6630 the value obtained from
6639 Note that when SMTP transport is not used (via
6641 then it is normally the responsibility of the MTA to create these
6642 fields, \*(IN in conjunction with SMTP however
6644 also influences the results:
6645 you should produce some test messages with the desired combination of
6654 \*(BO\*(OP Can be used to turn off the automatic conversion of domain
6655 names according to the rules of IDNA (internationalized domain names
6657 Since the IDNA code assumes that domain names are specified with the
6659 character set, an UTF-8 locale charset is required to represent all
6660 possible international domain names (before conversion, that is).
6664 \*(BO Ignore interrupt signals from the terminal while entering
6665 messages; instead echo them as
6667 characters and discard the current line.
6671 \*(BO Ignore end-of-file conditions
6672 .Pf ( Ql control-D )
6673 in compose mode on message input and in interactive command input.
6674 If set an interactive command input session can only be left by
6675 explicitly using one of the commands
6679 and message input in compose mode can only be terminated by entering
6682 on a line by itself or by using the
6684 .Sx "TILDE ESCAPES" ;
6686 overrides a setting of
6698 option for indenting messages,
6699 in place of the normal tabulator character
6701 which is the default.
6702 Be sure to quote the value if it contains spaces or tabs.
6706 \*(BO If set, an empty mailbox file is not removed.
6707 This may improve the interoperability with other mail user agents
6708 when using a common folder directory, and prevents malicious users
6709 from creating fake mailboxes in a world-writable spool directory.
6710 Note this only applies to local regular (MBOX) files, other mailbox
6711 types will never be removed.
6714 .It Va keep-content-length
6715 \*(BO When (editing messages and) writing
6717 mailbox files \*(UA can be told to keep the
6721 header fields that some MUAs generate by setting this variable.
6722 Since \*(UA does neither use nor update these non-standardized header
6723 fields (which in itself shows one of their conceptual problems),
6724 stripping them should increase interoperability in between MUAs that
6725 work with with same mailbox files.
6726 Note that, if this is not set but
6727 .Va writebackedited ,
6728 as below, is, a possibly performed automatic stripping of these header
6729 fields already marks the message as being modified.
6733 \*(BO When a message is saved it is usually discarded from the
6734 originating folder when \*(UA is quit.
6735 Setting this option causes all saved message to be retained.
6738 .It Va line-editor-disable
6739 \*(BO Turn off any enhanced line editing capabilities (see
6740 .Sx "On terminal control and line editor"
6744 .It Va line-editor-no-defaults
6745 \*(BO\*(OP Do not establish any default key binding.
6749 \*(BO When a message is replied to and this variable is set,
6750 it is marked as having been answered.
6751 This mark has no technical meaning in the mail system;
6752 it just causes messages to be marked in the header summary,
6753 and makes them specially addressable.
6757 \*(BO \*(UA generates and expects RFC 4155 compliant MBOX text
6759 (With the restriction that RFC 4155 defines seven-bit clean data
6760 storage, but which can be overwritten by a contrary setting of
6762 Messages which are fetched over the network or from within already
6763 existing Maildir (or any non-MBOX) mailboxes may require so-called
6765 quoting (insertion of additional
6767 characters to prevent line content misinterpretation) to be applied in
6768 order to be storable in MBOX mailboxes, however, dependent on the
6769 circumspection of the message producer.
6770 E.g., \*(UA itself will, when newly generating messages, choose a
6771 .Pf Content-Transfer- Va encoding
6772 that prevents the necessity for such quoting \(en a necessary
6773 precondition to ensure message checksums won't change.
6775 By default \*(UA will perform this
6777 quoting in a way that results in a MBOX file that is compatible with
6778 the POSIX MBOX layout, which means that, in order not to exceed the
6779 capabilities of simple applications, many more
6781 lines get quoted (thus modified) than necessary according to RFC 4155.
6782 Set this option to instead generate MBOX files which comply to RFC 4155.
6786 \*(BO Internal development variable.
6789 .It Va message-id-disable
6790 \*(BO By setting this option the generation of
6792 can be completely suppressed, effectively leaving this task up to the
6794 (Mail-Transfer-Agent) or the SMTP server.
6795 (According to RFC 5321 your SMTP server is not required to add this
6796 field by itself, so you should ensure that it accepts messages without a
6800 .It Va message-inject-head
6801 A string to put at the beginning of each new message.
6802 The escape sequences tabulator
6809 .It Va message-inject-tail
6810 A string to put at the end of each new message.
6811 The escape sequences tabulator
6819 \*(BO Usually, when an
6821 expansion contains the sender, the sender is removed from the expansion.
6822 Setting this option suppresses these removals.
6827 option to be passed through to the
6829 (Mail-Transfer-Agent); though most of the modern MTAs no longer document
6830 this flag, no MTA is known which doesn't support it (for historical
6834 .It Va mime-allow-text-controls
6835 \*(BO When sending messages, each part of the message is MIME-inspected
6836 in order to classify the
6839 .Ql Content-Transfer-Encoding:
6842 that is required to send this part over mail transport, i.e.,
6843 a computation rather similar to what the
6845 command produces when used with the
6849 This classification however treats text files which are encoded in
6850 UTF-16 (seen for HTML files) and similar character sets as binary
6851 octet-streams, forcefully changing any
6856 .Ql application/octet-stream :
6857 If that actually happens a yet unset charset MIME parameter is set to
6859 effectively making it impossible for the receiving MUA to automatically
6860 interpret the contents of the part.
6862 If this option is set, and the data was unambiguously identified as text
6863 data at first glance (by a
6867 file extension), then the original
6869 will not be overwritten.
6872 .It Va mime-alternative-favour-rich
6873 \*(BO If this variable is set then rich MIME alternative parts (e.g.,
6874 HTML) will be preferred in favour of included plain text versions when
6875 displaying messages, provided that a handler exists which produces
6876 output that can be (re)integrated into \*(UA's normal visual display.
6877 (E.g., at the time of this writing some newsletters ship their full
6878 content only in the rich HTML part, whereas the plain text part only
6879 contains topic subjects.)
6882 .It Va mime-counter-evidence
6885 field is used to decide how to handle MIME parts.
6886 Some MUAs however don't use
6888 or a similar mechanism to correctly classify content, but simply specify
6889 .Ql application/octet-stream ,
6890 even for plain text attachments like
6892 If this variable is set then \*(UA will try to classify such MIME
6893 message parts on its own, if possible, for example via a possibly
6894 existent attachment filename.
6895 A non-empty value may also be given, in which case a number is expected,
6896 actually a carrier of bits.
6897 Creating the bit-carrying number is a simple addition:
6898 .Bd -literal -offset indent
6899 ? !echo Value should be set to $((2 + 4 + 8))
6900 Value should be set to 14
6903 .Bl -bullet -compact
6905 If bit two is set (2) then the detected
6907 content-type will be carried along with the message and be used for
6909 .Va pipe-TYPE/SUBTYPE
6910 is responsible for the MIME part, shall that question arise;
6911 when displaying such a MIME part the part-info will indicate the
6912 overridden content-type by showing a plus-sign
6915 If bit three is set (4) then the counter-evidence is always produced
6916 and a positive result will be used as the MIME type, even forcefully
6917 overriding the parts given MIME type.
6919 If bit four is set (8) then as a last resort the actual content of
6920 .Ql application/octet-stream
6921 parts will be inspected, so that data which looks like plain text can be
6926 .It Va mimetypes-load-control
6927 This option can be used to control which of the
6929 databases are loaded by \*(UA, as furtherly described in the section
6930 .Sx "The mime.types files" .
6933 is part of the option value, then the user's personal
6935 file will be loaded (if it exists); likewise the letter
6937 controls loading of the system wide
6938 .Pa /etc/mime.types ;
6939 directives found in the user file take precedence, letter matching is
6941 If this option is not set \*(UA will try to load both files.
6942 Incorporation of the \*(UA-builtin MIME types cannot be suppressed,
6943 but they will be matched last.
6945 More sources can be specified by using a different syntax: if the
6946 value string contains an equals sign
6948 then it is instead parsed as a comma-separated list of the described
6951 pairs; the given filenames will be expanded and loaded, and their
6952 content may use the extended syntax that is described in the section
6953 .Sx "The mime.types files" .
6954 Directives found in such files always take precedence (are prepended to
6955 the MIME type cache).
6960 To choose an alternate Mail-Transfer-Agent, set this option to either
6961 the full pathname of an executable (optionally prefixed with a
6963 protocol indicator), or \*(OPally a SMTP protocol URL, e.g., \*(IN
6965 .Dl smtps?://[user[:password]@]server[:port]
6968 .Ql [smtp://]server[:port] . )
6969 The default has been chosen at compie time.
6970 All supported data transfers are executed in child processes, which
6971 run asynchronously, and without supervision, unless either the
6976 If such a child receives a TERM signal, it will abort and
6983 For a file-based MTA it may be necessary to set
6985 in in order to choose the right target of a modern
6988 It will be passed command line arguments from several possible sources:
6991 if set, from the command line if given and the variable
6994 Argument processing of the MTA will be terminated with a
6999 The otherwise occurring implicit usage of the following MTA command
7000 line arguments can be disabled by setting the boolean option
7001 .Va mta-no-default-arguments
7002 (which will also disable passing
7006 (for not treating a line with only a dot
7008 character as the end of input),
7016 option is set); in conjunction with the
7018 command line option \*(UA will also pass
7024 \*(OP \*(UA can send mail over SMTP network connections to a single
7025 defined SMTP smarthost, the access URL of which has to be assigned to
7027 To use this mode it is helpful to read
7028 .Sx "On URL syntax and credential lookup" .
7029 It may be necessary to set the
7031 variable in order to use a specific combination of
7036 with some mail providers.
7039 .Bl -bullet -compact
7041 The plain SMTP protocol (RFC 5321) that normally lives on the
7042 server port 25 and requires setting the
7043 .Va smtp-use-starttls
7044 variable to enter a SSL/TLS encrypted session state.
7045 Assign a value like \*(IN
7046 .Ql smtp://[user[:password]@]server[:port]
7048 .Ql smtp://server[:port] )
7049 to choose this protocol.
7051 The so-called SMTPS which is supposed to live on server port 465
7052 and is automatically SSL/TLS secured.
7053 Unfortunately it never became a standardized protocol and may thus not
7054 be supported by your hosts network service database
7055 \(en in fact the port number has already been reassigned to other
7058 SMTPS is nonetheless a commonly offered protocol and thus can be
7059 chosen by assigning a value like \*(IN
7060 .Ql smtps://[user[:password]@]server[:port]
7062 .Ql smtps://server[:port] ) ;
7063 due to the mentioned problems it is usually necessary to explicitly
7068 Finally there is the SUBMISSION protocol (RFC 6409), which usually
7069 lives on server port 587 and is practically identically to the SMTP
7070 protocol from \*(UA's point of view beside that; it requires setting the
7071 .Va smtp-use-starttls
7072 variable to enter a SSL/TLS secured session state.
7073 Assign a value like \*(IN
7074 .Ql submission://[user[:password]@]server[:port]
7076 .Ql submission://server[:port] ) .
7081 .It Va mta-arguments
7082 Arguments to pass through to a file-based
7084 can be given via this variable, the content of which will be split up in
7085 a vector of arguments, to be joined onto other possible MTA options:
7087 .Dl set mta-arguments='-t -X \&"/tmp/my log\&"'
7090 .It Va mta-no-default-arguments
7091 \*(BO Unless this option is set \*(UA will pass some well known
7092 standard command line options to a file-based
7094 (Mail-Transfer-Agent), see there for more.
7098 Many systems use a so-called
7100 environment to ensure compatibility with
7102 This works by inspecting the name that was used to invoke the mail
7104 If this variable is set then the mailwrapper (the program that is
7105 actually executed when calling the file-based
7107 will treat its contents as that name.
7112 .It Va NAIL_EXTRA_RC
7113 The name of an optional startup file to be read last.
7114 This variable has an effect only if it is set in any of the
7115 .Sx "Resource files" ,
7116 it is not imported from the environment.
7117 Use this file for commands that are not understood by other POSIX
7122 .It Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup
7123 \*(BO\*(IN\*(OP Used to control usage of the users
7125 file for lookup of account credentials, as documented in the section
7126 .Sx "On URL syntax and credential lookup"
7130 .Sx "The .netrc file"
7131 documents the file format.
7143 then \*(UA will read the output of a shell pipe instead of the users
7145 file if this variable is set (to the desired shell command).
7146 This can be used to, e.g., store
7150 .Dl set netrc-pipe='gpg -qd ~/.netrc.pgp'
7154 If this variable has the value
7156 newly created local folders will be in Maildir format.
7160 Checks for new mail in the current folder each time the prompt is shown.
7161 A Maildir folder must be re-scanned to determine if new mail has arrived.
7162 If this variable is set to the special value
7164 then a Maildir folder will not be rescanned completely, but only
7165 timestamp changes are detected.
7169 .It Va on-compose-enter , on-compose-leave
7170 \*(ID Macro hooks which will be executed before compose mode is
7171 entered, and after composing has been finished, respectively.
7172 Please note that this interface is very likely to change in v15, and
7173 should therefore possibly even be seen as experimental.
7175 are by default enabled for these hooks, causing any setting to be
7176 forgotten after the message has been sent.
7177 The following variables will be set temporarily during execution of the
7180 .Bl -tag -compact -width ".It Va compose_subject"
7183 .It Va compose-sender
7185 .It Va compose-to , compose-cc , compose-bcc
7186 The list of receiver addresses as a space-separated list.
7187 .It Va compose-subject
7193 \*(BO Causes the filename given in the
7196 and the sender-based filenames for the
7200 commands to be interpreted relative to the directory given in the
7202 variable rather than to the current directory,
7203 unless it is set to an absolute pathname.
7207 \*(BO If set, each message feed through the command given for
7209 is followed by a formfeed character
7213 .It Va password-USER@HOST , password-HOST , password
7214 \*(IN Variable chain that sets a password, which is used in case none has
7215 been given in the protocol and account-specific URL;
7216 as a last resort \*(UA will ask for a password on the user's terminal if
7217 the authentication method requires a password.
7218 Specifying passwords in a startup file is generally a security risk;
7219 the file should be readable by the invoking user only.
7221 .It Va password-USER@HOST
7222 \*(OU (see the chain above for \*(IN)
7223 Set the password for
7227 If no such variable is defined for a host,
7228 the user will be asked for a password on standard input.
7229 Specifying passwords in a startup file is generally a security risk;
7230 the file should be readable by the invoking user only.
7234 \*(BO Send messages to the
7236 command without performing MIME and character set conversions.
7240 .It Va pipe-TYPE/SUBTYPE
7241 When a MIME message part of type
7243 (case-insensitive) is displayed or quoted,
7244 its text is filtered through the value of this variable interpreted as
7248 forces interpretation of the message part as plain text, e.g.,
7249 .Ql set pipe-application/xml=@
7250 will henceforth display XML
7252 (The same could also be achieved by adding a MIME type marker with the
7255 And \*(OPally MIME type handlers may be defined via
7256 .Sx "The Mailcap files"
7257 \(em corresponding flag strings are shown in parenthesis below.)
7262 can in fact be used to adjust usage and behaviour of a following shell
7263 command specification by appending trigger characters to it, e.g., the
7264 following hypothetical command specification could be used:
7265 .Bd -literal -offset indent
7266 set pipe-X/Y='@*!++=@vim ${NAIL_FILENAME_TEMPORARY}'
7270 .Bl -tag -compact -width ".It Ql __"
7272 Simply by using the special
7274 prefix the MIME type (shell command) handler will only be invoked to
7275 display or convert the MIME part if the message is addressed directly
7276 and alone by itself.
7277 Use this trigger to disable this and always invoke the handler
7278 .Pf ( Cd x-mailx-always ) .
7281 If set the handler will not be invoked when a message is to be quoted,
7282 but only when it will be displayed
7283 .Pf ( Cd x-mailx-noquote ) .
7286 The command will be run asynchronously, i.e., without blocking \*(UA,
7287 which may be a handy way to display a, e.g., PDF file while also
7288 continuing to read the mail message
7289 .Pf ( Cd x-mailx-async ) .
7290 Asynchronous execution implies
7294 The command must be run on an interactive terminal, \*(UA will
7295 temporarily release the terminal to it
7296 .Pf ( Cd needsterminal ) .
7297 This flag is mutual exclusive with
7299 will only be used in interactive mode and implies
7303 Request creation of a zero-sized temporary file, the absolute pathname
7304 of which will be made accessible via the environment variable
7305 .Ev NAIL_FILENAME_TEMPORARY
7306 .Pf ( Cd x-mailx-tmpfile ) .
7307 If this trigger is given twice then the file will be unlinked
7308 automatically by \*(UA when the command loop is entered again at latest
7309 .Pf ( Cd x-mailx-tmpfile-unlink ) .
7310 (Don't use this for asynchronous handlers.)
7313 Normally the MIME part content is passed to the handler via standard
7314 input; if this flag is set then the data will instead be written into
7315 .Ev NAIL_FILENAME_TEMPORARY
7316 .Pf ( Cd x-mailx-tmpfile-fill ) ,
7317 the creation of which is implied; note however that in order to cause
7318 deletion of the temporary file you still have to use two plus signs
7323 To avoid ambiguities with normal shell command content you can use
7324 another at-sign to forcefully terminate interpretation of remaining
7326 (Any character not in this list will have the same effect.)
7330 Some information about the MIME part to be displayed is embedded into
7331 the environment of the shell command:
7334 .Bl -tag -compact -width ".It Ev _AIL__ILENAME__ENERATED"
7337 The MIME content-type of the part, if known, the empty string otherwise.
7340 .It Ev NAIL_CONTENT_EVIDENCE
7342 .Va mime-counter-evidence
7343 includes the carry-around-bit (2), then this will be set to the detected
7344 MIME content-type; not only then identical to
7345 .Ev \&\&NAIL_CONTENT
7349 .It Ev NAIL_FILENAME
7350 The filename, if any is set, the empty string otherwise.
7353 .It Ev NAIL_FILENAME_GENERATED
7357 .It Ev NAIL_FILENAME_TEMPORARY
7358 If temporary file creation has been requested through the command prefix
7359 this variable will be set and contain the absolute pathname of the
7364 The temporary directory that \*(UA uses.
7365 Usually identical to
7367 but guaranteed to be set and usable by child processes;
7368 to ensure the latter condition for
7375 .It Va pipe-EXTENSION
7376 This is identical to
7377 .Va pipe-TYPE/SUBTYPE
7380 (normalized to lowercase using character mappings of the ASCII charset)
7381 names a file extension, e.g.,
7383 Handlers registered using this method take precedence.
7386 .It Va pop3-auth-USER@HOST , pop3-auth-HOST , pop3-auth
7387 \*(OP\*(IN Variable chain that sets the POP3 authentication method.
7388 The only possible value as of now is
7390 which is thus the default.
7393 .Mx Va pop3-bulk-load
7394 .It Va pop3-bulk-load-USER@HOST , pop3-bulk-load-HOST , pop3-bulk-load
7395 \*(BO\*(OP When accessing a POP3 server \*(UA loads the headers of
7396 the messages, and only requests the message bodies on user request.
7397 For the POP3 protocol this means that the message headers will be
7399 If this option is set then \*(UA will download only complete messages
7400 from the given POP3 server(s) instead.
7402 .Mx Va pop3-keepalive
7403 .It Va pop3-keepalive-USER@HOST , pop3-keepalive-HOST , pop3-keepalive
7404 \*(OP POP3 servers close the connection after a period of inactivity;
7405 the standard requires this to be at least 10 minutes,
7406 but practical experience may vary.
7407 Setting this variable to a numeric value greater than
7411 command to be sent each value seconds if no other operation is performed.
7414 .It Va pop3-no-apop-USER@HOST , pop3-no-apop-HOST , pop3-no-apop
7415 \*(BO\*(OP Unless this variable is set the
7417 authentication method will be used when connecting to a POP3 server that
7421 is that the password is not sent in clear text over the wire and that
7422 only a single packet is sent for the user/password tuple.
7424 .Va pop3-no-apop-HOST
7427 .Mx Va pop3-use-starttls
7428 .It Va pop3-use-starttls-USER@HOST , pop3-use-starttls-HOST , pop3-use-starttls
7429 \*(BO\*(OP Causes \*(UA to issue a
7431 command to make an unencrypted POP3 session SSL/TLS encrypted.
7432 This functionality is not supported by all servers,
7433 and is not used if the session is already encrypted by the POP3S method.
7435 .Va pop3-use-starttls-HOST
7439 .It Va print-alternatives
7440 \*(BO When a MIME message part of type
7441 .Ql multipart/alternative
7442 is displayed and it contains a subpart of type
7444 other parts are normally discarded.
7445 Setting this variable causes all subparts to be displayed,
7446 just as if the surrounding part was of type
7447 .Ql multipart/mixed .
7451 The string shown when a command is accepted.
7452 Prompting may be prevented by setting this to the null string
7454 .Pf no Va prompt ) .
7455 If a value is assigned the following \*(UA specific additional sequences
7462 is set, in which case it expands to
7466 is the default value of
7469 which will expand to
7471 if the last command failed and to
7475 which will expand to the name of the currently active
7477 if any, and to the empty string otherwise, and
7479 which will expand to the name of the currently active mailbox.
7480 (Note that the prompt buffer is size-limited, excess is cut off.)
7486 to encapsulate the expansions of the
7490 escape sequences as necessary to correctly display bidirectional text,
7491 this is not true for the final string that makes up
7493 as such, i.e., real BIDI handling is not supported.
7497 \*(BO Suppresses the printing of the version when first invoked.
7501 If set, \*(UA starts a replying message with the original message
7502 prefixed by the value of the variable
7504 Normally, a heading consisting of
7505 .Dq Fromheaderfield wrote:
7506 is put before the quotation.
7511 variable, this heading is omitted.
7514 is assigned, the headers selected by the
7515 .Ic ignore Ns / Ns Ic retain
7516 commands are put above the message body,
7519 acts like an automatic
7525 is assigned, all headers are put above the message body and all MIME
7526 parts are included, making
7528 act like an automatic
7531 .Va quote-as-attachment .
7534 .It Va quote-as-attachment
7535 \*(BO Add the original message in its entirety as a
7537 MIME attachment when replying to a message.
7538 Note this works regardless of the setting of
7543 \*(OP Can be set in addition to
7545 Setting this turns on a more fancy quotation algorithm in that leading
7546 quotation characters are compressed and overlong lines are folded.
7548 can be set to either one or two (space separated) numeric values,
7549 which are interpreted as the maximum (goal) and the minimum line length,
7550 respectively, in a spirit rather equal to the
7552 program, but line-, not paragraph-based.
7553 If not set explicitly the minimum will reflect the goal algorithmically.
7554 The goal can't be smaller than the length of
7556 plus some additional pad.
7557 Necessary adjustments take place silently.
7560 .It Va recipients-in-cc
7561 \*(BO On group replies, specify only the sender of the original mail in
7563 and mention the other recipients in the secondary
7565 By default all recipients of the original mail will be addressed via
7570 If defined, gives the pathname of the folder used to record all outgoing
7572 If not defined, then outgoing mail is not saved.
7573 When saving to this folder fails the message is not sent,
7574 but instead saved to
7578 .It Va record-resent
7579 \*(BO If both this variable and the
7586 commands save messages to the
7588 folder as it is normally only done for newly composed messages.
7591 .It Va reply-in-same-charset
7592 \*(BO If this variable is set \*(UA first tries to use the same
7593 character set of the original message for replies.
7594 If this fails, the mechanism described in
7595 .Sx "Character sets"
7596 is evaluated as usual.
7599 .It Va reply_strings
7600 Can be set to a comma-separated list of (case-insensitive according to
7601 ASCII rules) strings which shall be recognized in addition to the
7604 reply message indicators \(en builtin are
7606 which is mandated by RFC 5322, as well as the german
7611 A list of addresses to put into the
7613 field of the message header.
7614 Members of this list are handled as if they were in the
7619 .It Va reply-to-honour
7622 header is honoured when replying to a message via
7626 This is a quadoption; if set without a value it defaults to
7630 .It Va rfc822-body-from_
7631 \*(BO This variable can be used to force displaying a so-called
7633 line for messages that are embedded into an envelope mail via the
7635 MIME mechanism, for more visual convenience.
7639 \*(BO Enable saving of (partial) messages in
7641 upon interrupt or delivery error.
7645 The number of lines that represents a
7654 line display and scrolling via
7656 If this variable is not set \*(UA falls back to a calculation based upon
7657 the detected terminal window size and the baud rate: the faster the
7658 terminal, the more will be shown.
7659 Overall screen dimensions and pager usage is influenced by the
7660 environment variables
7668 .It Va searchheaders
7669 \*(BO Expand message-list specifiers in the form
7671 to all messages containing the substring
7675 The string search is case insensitive.
7679 \*(OP A comma-separated list of character set names that can be used in
7680 outgoing internet mail.
7681 The value of the variable
7683 is automatically appended to this list of character-sets.
7684 If no character set conversion capabilities are compiled into \*(UA then
7685 the only supported charset is
7688 .Va sendcharsets-else-ttycharset
7689 and refer to the section
7690 .Sx "Character sets"
7691 for the complete picture of character set conversion in \*(UA.
7694 .It Va sendcharsets-else-ttycharset
7695 \*(BO\*(OP If this variable is set, but
7697 is not, then \*(UA acts as if
7699 had been set to the value of the variable
7701 In effect this combination passes through the message data in the
7702 character set of the current locale (given that
7704 hasn't been set manually), i.e., without converting it to the
7706 fallback character set.
7707 Thus, mail message text will be in ISO-8859-1 encoding when send from
7708 within a ISO-8859-1 locale, and in UTF-8 encoding when send from within
7710 If no character set conversion capabilities are available in \*(UA then
7711 the only supported character set is
7716 An address that is put into the
7718 field of outgoing messages, quoting RFC 5322: the mailbox of the agent
7719 responsible for the actual transmission of the message.
7720 This field should normally not be used unless the
7722 field contains more than one address, on which case it is required.
7725 address is handled as if it were in the
7731 \*(OB Predecessor of
7735 .It Va sendmail-arguments
7736 \*(OB Predecessor of
7740 .It Va sendmail-no-default-arguments
7741 \*(OB\*(BO Predecessor of
7742 .Va mta-no-default-arguments .
7745 .It Va sendmail-progname
7746 \*(OB Predecessor of
7751 \*(BO When sending a message wait until the
7753 (including the builtin SMTP one) exits before accepting further commands.
7755 with this variable set errors reported by the MTA will be recognizable!
7756 If the MTA returns a non-zero exit status,
7757 the exit status of \*(UA will also be non-zero.
7761 \*(BO Setting this option causes \*(UA to start at the last message
7762 instead of the first one when opening a mail folder.
7766 \*(BO Causes \*(UA to use the sender's real name instead of the plain
7767 address in the header field summary and in message specifications.
7771 \*(BO Causes the recipient of the message to be shown in the header
7772 summary if the message was sent by the user.
7776 A string for use with the
7782 A string for use with the
7788 Must correspond to the name of a readable file if set.
7789 The file's content is then appended to each singlepart message
7790 and to the first part of each multipart message.
7791 Be warned that there is no possibility to edit the signature for an
7795 .It Va skipemptybody
7796 \*(BO If an outgoing message does not contain any text in its first or
7797 only message part, do not send it but discard it silently (see also the
7803 \*(OP Specifies a directory with CA certificates in PEM (Privacy
7804 Enhanced Mail) format for verification of S/MIME signed messages.
7807 .It Va smime-ca-file
7808 \*(OP Specifies a file with CA certificates in PEM format for
7809 verification of S/MIME signed messages.
7812 .It Va smime-cipher-USER@HOST , smime-cipher
7813 \*(OP Specifies the cipher to use when generating S/MIME encrypted
7814 messages (for the specified account).
7815 RFC 5751 mandates a default of
7818 Possible values are (case-insensitive and) in decreasing cipher strength:
7826 (DES EDE3 CBC, 168 bits; default if
7828 isn't available) and
7832 The actually available cipher algorithms depend on the cryptographic
7833 library that \*(UA uses.
7834 \*(OP Support for more cipher algorithms may be available through
7835 dynamic loading via, e.g.,
7836 .Xr EVP_get_cipherbyname 3
7837 (OpenSSL) if \*(UA has been compiled to support this.
7840 .It Va smime-crl-dir
7841 \*(OP Specifies a directory that contains files with CRLs in PEM format
7842 to use when verifying S/MIME messages.
7845 .It Va smime-crl-file
7846 \*(OP Specifies a file that contains a CRL in PEM format to use when
7847 verifying S/MIME messages.
7850 .It Va smime-encrypt-USER@HOST
7851 \*(OP If this variable is set, messages send to the given receiver are
7852 encrypted before sending.
7853 The value of the variable must be set to the name of a file that
7854 contains a certificate in PEM format.
7856 If a message is sent to multiple recipients,
7857 each of them for whom a corresponding variable is set will receive an
7858 individually encrypted message;
7859 other recipients will continue to receive the message in plain text
7861 .Va smime-force-encryption
7863 It is recommended to sign encrypted messages, i.e., to also set the
7868 .It Va smime-force-encryption
7869 \*(BO\*(OP Causes \*(UA to refuse sending unencrypted messages.
7872 .It Va smime-no-default-ca
7873 \*(BO\*(OP Don't load default CA locations when verifying S/MIME signed
7878 \*(BO\*(OP S/MIME sign outgoing messages with the user's private key
7879 and include the user's certificate as a MIME attachment.
7880 Signing a message enables a recipient to verify that the sender used
7881 a valid certificate,
7882 that the email addresses in the certificate match those in the message
7883 header and that the message content has not been altered.
7884 It does not change the message text,
7885 and people will be able to read the message as usual.
7887 .Va smime-sign-cert , smime-sign-include-certs
7889 .Va smime-sign-message-digest .
7891 .Mx Va smime-sign-cert
7892 .It Va smime-sign-cert-USER@HOST , smime-sign-cert
7893 \*(OP Points to a file in PEM format.
7894 For the purpose of signing and decryption this file needs to contain the
7895 user's private key as well as his certificate.
7899 is always derived from the value of
7901 (or, if that contains multiple addresses,
7903 For the purpose of encryption the recipient's public encryption key
7904 (certificate) is expected; the command
7906 can be used to save certificates of signed messages (the section
7907 .Sx "Signed and encrypted messages with S/MIME"
7908 gives some details).
7909 This mode of operation is usually driven by the specialized form.
7911 When decrypting messages the account is derived from the recipient
7916 of the message, which are searched for addresses for which such
7918 \*(UA always uses the first address that matches,
7919 so if the same message is sent to more than one of the user's addresses
7920 using different encryption keys, decryption might fail.
7922 .Mx Va smime-sign-include-certs
7923 .It Va smime-sign-include-certs-USER@HOST , smime-sign-include-certs
7924 \*(OP If used, this is supposed to a consist of a comma-separated list
7925 of files, each of which containing a single certificate in PEM format to
7926 be included in the S/MIME message in addition to the
7929 This is most useful for long certificate chains if it is desired to aid
7930 the receiving party's verification process.
7931 Note that top level certificates may also be included in the chain but
7932 don't play a role for verification.
7934 .Va smime-sign-cert .
7935 Remember that for this
7937 refers to the variable
7939 (or, if that contains multiple addresses,
7942 .Mx Va smime-sign-message-digest
7943 .It Va smime-sign-message-digest-USER@HOST , smime-sign-message-digest
7944 \*(OP Specifies the message digest to use when signing S/MIME messages.
7945 RFC 5751 mandates a default of
7947 Possible values are (case-insensitive and) in decreasing cipher strength:
7955 The actually available message digest algorithms depend on the
7956 cryptographic library that \*(UA uses.
7957 \*(OP Support for more message digest algorithms may be available
7958 through dynamic loading via, e.g.,
7959 .Xr EVP_get_digestbyname 3
7960 (OpenSSL) if \*(UA has been compiled to support this.
7961 Remember that for this
7963 refers to the variable
7965 (or, if that contains multiple addresses,
7970 \*(OB\*(OP To use the builtin SMTP transport, specify a SMTP URL in
7972 \*(ID For compatibility reasons a set
7974 is used in preference of
7978 .It Va smtp-auth-USER@HOST , smtp-auth-HOST , smtp-auth
7979 \*(OP Variable chain that controls the SMTP
7981 authentication method, possible values are
7987 as well as the \*(OPal methods
7993 method doesn't need any user credentials,
7995 requires a user name and all other methods require a user name and
8003 .Va smtp-auth-password
8005 .Va smtp-auth-user ) .
8010 .Va smtp-auth-USER@HOST :
8011 may override dependent on sender address in the variable
8014 .It Va smtp-auth-password
8015 \*(OP\*(OU Sets the global fallback password for SMTP authentication.
8016 If the authentication method requires a password, but neither
8017 .Va smtp-auth-password
8019 .Va smtp-auth-password-USER@HOST
8021 \*(UA will ask for a password on the user's terminal.
8023 .It Va smtp-auth-password-USER@HOST
8025 .Va smtp-auth-password
8026 for specific values of sender addresses, dependent upon the variable
8029 .It Va smtp-auth-user
8030 \*(OP\*(OU Sets the global fallback user name for SMTP authentication.
8031 If the authentication method requires a user name, but neither
8034 .Va smtp-auth-user-USER@HOST
8036 \*(UA will ask for a user name on the user's terminal.
8038 .It Va smtp-auth-user-USER@HOST
8041 for specific values of sender addresses, dependent upon the variable
8045 .It Va smtp-hostname
8046 \*(OP\*(IN Normally \*(UA uses the variable
8048 to derive the necessary
8050 information in order to issue a
8057 can be used to use the
8059 from the SMTP account
8066 from the content of this variable (or, if that is the empty string,
8068 or the local hostname as a last resort).
8069 This often allows using an address that is itself valid but hosted by
8070 a provider other than which (in
8072 is about to send the message.
8073 Setting this variable also influences the generated
8076 .Mx Va smtp-use-starttls
8077 .It Va smtp-use-starttls-USER@HOST , smtp-use-starttls-HOST , smtp-use-starttls
8078 \*(BO\*(OP Causes \*(UA to issue a
8080 command to make an SMTP
8082 session SSL/TLS encrypted, i.e., to enable transport layer security.
8086 .It Va spam-interface
8087 \*(OP In order to use any of the spam-related commands (like, e.g.,
8089 the desired spam interface must be defined by setting this variable.
8090 Please refer to the manual section
8092 for the complete picture of spam handling in \*(UA.
8093 All or none of the following interfaces may be available:
8095 .Bl -tag -width ".It Ql _ilte_"
8101 .Pf ( Lk http://spamassassin.apache.org SpamAssassin )
8103 Different to the generic filter interface \*(UA will automatically add
8104 the correct arguments for a given command and has the necessary
8105 knowledge to parse the program's output.
8108 will have been compiled into the \*(UA binary if
8113 Shall it be necessary to define a specific connection type (rather than
8114 using a configuration file for that), the variable
8116 can be used as in, e.g.,
8117 .Ql -d server.example.com -p 783 .
8118 It is also possible to specify a per-user configuration via
8120 Note that this interface doesn't inspect the
8122 flag of a message for the command
8126 generic spam filter support via freely configurable hooks.
8127 This interface is meant for programs like
8129 and requires according behaviour in respect to the hooks' exit
8130 status for at least the command
8133 meaning a message is spam,
8137 for unsure and any other return value indicating a hard error);
8138 since the hooks can include shell code snippets diverting behaviour
8139 can be intercepted as necessary.
8141 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
8144 .Va spamfilter-spam ;
8147 contains examples for some programs.
8148 The process environment of the hooks will have the variables
8149 .Ev NAIL_TMPDIR , TMPDIR
8151 .Ev NAIL_FILENAME_GENERATED
8153 Note that spam score support for
8155 isn't supported unless the \*(OPtional regular expression support is
8157 .Va spamfilter-rate-scanscore
8164 \*(OP Messages that exceed this size won't be passed through to the
8166 .Va spam-interface .
8167 If unset or 0, the default of 420000 bytes is used.
8170 .It Va spamc-command
8171 \*(OP The path to the
8175 .Va spam-interface .
8176 Note that the path is not expanded, but used
8178 A fallback path will have been compiled into the \*(UA binary if the
8179 executable had been found during compilation.
8182 .It Va spamc-arguments
8183 \*(OP Even though \*(UA deals with most arguments for the
8186 automatically, it may at least sometimes be desirable to specify
8187 connection-related ones via this variable, e.g.,
8188 .Ql -d server.example.com -p 783 .
8192 \*(OP Specify a username for per-user configuration files for the
8194 .Va spam-interface .
8195 If this is set to the empty string then \*(UA will use the name of the
8204 .It Va spamfilter-ham , spamfilter-noham , \
8205 spamfilter-nospam , spamfilter-rate , spamfilter-spam
8206 \*(OP Command and argument hooks for the
8208 .Va spam-interface .
8211 contains examples for some programs.
8214 .It Va spamfilter-rate-scanscore
8215 \*(OP Because of the generic nature of the
8218 spam scores are not supported for it by default, but if the \*(OPtional
8219 regular expression support is available then setting this variable can
8220 be used to overcome this restriction.
8221 It is interpreted as follows: first a number (digits) is parsed that
8222 must be followed by a semicolon
8224 and an extended regular expression.
8225 Then the latter is used to parse the first output line of the
8227 hook, and, in case the evaluation is successful, the group that has been
8228 specified via the number is interpreted as a floating point scan score.
8232 \*(OP Specifies a directory with CA certificates in PEM (Pricacy
8233 Enhanced Mail) for verification of of SSL/TLS server certificates.
8235 .Xr SSL_CTX_load_verify_locations 3
8236 for more information.
8240 \*(OP Specifies a file with CA certificates in PEM format for
8241 verification of SSL/TLS server certificates.
8243 .Xr SSL_CTX_load_verify_locations 3
8244 for more information.
8247 .It Va ssl-cert-USER@HOST , ssl-cert-HOST , ssl-cert
8248 \*(OP Variable chain that sets the file name for a SSL/TLS client
8249 certificate required by some servers.
8250 This is a direct interface to the
8254 function of the OpenSSL library, if available.
8256 .Mx Va ssl-cipher-list
8257 .It Va ssl-cipher-list-USER@HOST , ssl-cipher-list-HOST , ssl-cipher-list
8258 \*(OP Specifies a list of ciphers for SSL/TLS connections.
8259 This is a direct interface to the
8263 function of the OpenSSL library, if available; see
8265 for more information.
8266 By default \*(UA doesn't set a list of ciphers, which in effect will use a
8268 specific cipher (protocol standards ship with a list of acceptable
8269 ciphers), possibly cramped to what the actually used SSL/TLS library
8270 supports \(en the manual section
8271 .Sx "An example configuration"
8272 also contains a SSL/TLS use case.
8275 .It Va ssl-config-file
8276 \*(OP If this variable is set \*(UA will call
8277 .Xr CONF_modules_load_file 3
8278 to allow OpenSSL to be configured according to the host system wide
8280 If a non-empty value is given then this will be used to specify the
8281 configuration file to be used instead of the global OpenSSL default;
8282 note that in this case it is an error if the file cannot be loaded.
8283 The application name will always be passed as
8288 \*(OP Specifies a file that contains a CRL in PEM format to use when
8289 verifying SSL/TLS server certificates.
8293 \*(OP Specifies a directory that contains files with CRLs in PEM format
8294 to use when verifying SSL/TLS server certificates.
8297 .It Va ssl-key-USER@HOST , ssl-key-HOST , ssl-key
8298 \*(OP Variable chain that sets the file name for the private key of
8299 a SSL/TLS client certificate.
8300 If unset, the name of the certificate file is used.
8301 The file is expected to be in PEM format.
8302 This is a direct interface to the
8306 function of the OpenSSL library, if available.
8309 .It Va ssl-method-USER@HOST , ssl-method-HOST , ssl-method
8310 \*(OB\*(OP Please use the newer and more flexible
8312 instead: if both values are set,
8314 will take precedence!
8315 Can be set to the following values, the actually used
8317 specification to which it is mapped is shown in parenthesis:
8319 .Pf ( Ql -ALL, TLSv1.2 ) ,
8321 .Pf ( Ql -ALL, TLSv1.1 ) ,
8323 .Pf ( Ql -ALL, TLSv1 )
8326 .Pf ( Ql -ALL, SSLv3 ) ;
8331 and thus includes the SSLv3 protocol.
8332 Note that SSLv2 is no longer supported at all.
8335 .It Va ssl-no-default-ca
8336 \*(BO\*(OP Don't load default CA locations to verify SSL/TLS server
8340 .It Va ssl-protocol-USER@HOST , ssl-protocol-HOST , ssl-protocol
8341 \*(OP Specify the used SSL/TLS protocol.
8342 This is a direct interface to the
8346 function of the OpenSSL library, if available;
8347 otherwise an \*(UA internal parser is used which understands the
8348 following subset of (case-insensitive) command strings:
8354 as well as the special value
8356 Multiple specifications may be given via a comma-separated list which
8357 ignores any whitespace.
8360 plus prefix will enable a protocol, a
8362 minus prefix will disable it, so that
8364 will enable only the TLSv1.2 protocol.
8366 It depends upon the used TLS/SSL library which protocols are actually
8367 supported and which protocols are used if
8369 is not set, but note that SSLv2 is no longer supported at all and
8371 Especially for older protocols explicitly securing
8373 may be worthwile, see
8374 .Sx "An example configuration" .
8378 \*(OP Gives the pathname to an entropy daemon socket, see
8380 Not all SSL/TLS libraries support this.
8383 .It Va ssl-rand-file
8384 \*(OP Gives the filename to a file with random entropy data, see
8385 .Xr RAND_load_file 3 .
8386 If this variable is not set, or set to the empty string, or if the
8387 filename expansion failed, then
8388 .Xr RAND_file_name 3
8389 will be used to create the filename if, and only if,
8391 documents that the SSL PRNG is not yet sufficiently seeded.
8392 If \*(UA successfully seeded the SSL PRNG then it'll update the file via
8393 .Xr RAND_write_file 3 .
8394 This variable is only used if
8396 is not set (or not supported by the SSL/TLS library).
8399 .It Va ssl-verify-USER@HOST , ssl-verify-HOST , ssl-verify
8400 \*(OP Variable chain that sets the action to be performed if an error
8401 occurs during SSL/TLS server certificate validation.
8402 Valid (case-insensitive) values are
8404 (fail and close connection immediately),
8406 (ask whether to continue on standard input),
8408 (show a warning and continue),
8410 (do not perform validation).
8416 If only set without an assigned value, then this option inhibits the
8421 header fields that include obvious references to \*(UA.
8422 There are two pitfalls associated with this:
8423 First, the message id of outgoing messages is not known anymore.
8424 Second, an expert may still use the remaining information in the header
8425 to track down the originating mail user agent.
8430 suppression doesn't occur.
8435 (\*(OP) This specifies a comma-separated list of
8440 .Sx "On terminal control and line editor" ,
8441 escape commas with reverse solidus) to be used to overwrite or define
8443 Note that this variable will only be queried once at program startup and
8444 can thus only be specified in resource files or on the command line.
8447 String capabilities form
8449 pairs and are expected unless noted otherwise.
8450 Numerics have to be notated as
8452 where the number is expected in normal decimal notation.
8453 Finally, booleans don't have any value but indicate a true or false
8454 state simply by being defined or not; this indeed means that \*(UA
8455 doesn't support undefining an existing boolean.
8456 String capability values will undergo some expansions before use:
8457 for one notations like
8460 .Ql control-LETTER ,
8461 and for clarification purposes
8463 can be used to specify
8465 (the control notation
8467 could lead to misreadings when a left bracket follows, which it does for
8468 the standard CSI sequence);
8469 finally three letter octal sequences, as in
8472 To specify that a terminal supports 256-colours, and to define sequences
8473 that home the cursor and produce an audible bell, one might write:
8475 .Bd -literal -offset indent
8476 set termcap='Co#256,home=\eE[H,bel=^G'
8480 The following terminal capabilities are or may be meaningful for the
8481 operation of the builtin line editor or \*(UA in general:
8484 .Bl -tag -compact -width yay
8486 .It Cd colors Ns \0or Cd Co
8488 numeric capability specifying the maximum number of colours.
8489 Note that \*(UA doesn't actually care about the terminal beside that,
8490 but always emits ANSI / ISO 6429 escape sequences.
8493 .It Cd rmcup Ns \0or Cd te Ns \0/ Cd smcup Ns \0or Cd ti
8497 respectively: exit and enter the alternative screen
8499 effectively turning \*(UA into a fullscreen application.
8500 To disable that, set (at least) one to the empty string.
8502 .It Cd smkx Ns \0or Cd ks Ns \0/ Cd rmkx Ns \0or Cd ke
8506 respectively: enable and disable the keypad.
8507 This is always enabled if available, because it seems even keyboards
8508 without keypads generate other key codes for, e.g., cursor keys in that
8509 case, and only if enabled we see the codes that we are interested in.
8511 .It Cd ed Ns \0or Cd cd
8515 .It Cd clear Ns \0or Cd cl
8517 clear the screen and home cursor.
8518 (Will be simulated via
8523 .It Cd home Ns \0or Cd ho
8528 .It Cd el Ns \0or Cd ce
8530 clear to the end of line.
8531 (Will be simulated via
8533 plus repetitions of space characters.)
8535 .It Cd hpa Ns \0or Cd ch
8536 .Cd column_address :
8537 move the cursor (to the given column parameter) in the current row.
8538 (Will be simulated via
8544 .Cd carriage_return :
8545 move to the first column in the current row.
8546 The default builtin fallback is
8549 .It Cd cub1 Ns \0or Cd le
8551 move the cursor left one space (non-destructively).
8552 The default builtin fallback is
8555 .It Cd cuf1 Ns \0or Cd nd
8557 move the cursor right one space (non-destructively).
8558 The default builtin fallback is
8560 which is used by most terminals.
8568 Many more capabilities which describe key-sequences are documented for
8572 .It Va termcap-disable
8573 \*(OP Disable any interaction with a terminal control library.
8574 If set only some generic fallback builtins and possibly the content of
8576 describe the terminal to \*(UA.
8578 that this variable will only be queried once at program startup and can
8579 thus only be specified in resource files or on the command line.
8583 If defined, gives the number of lines of a message to be displayed
8586 if unset, the first five lines are printed, if set to 0 the variable
8589 If the value is negative then its absolute value will be used for right
8592 height; (shifting bitwise is like dividing algorithmically, but since
8593 it takes away bits the value decreases pretty fast).
8597 \*(BO If set then the
8599 command series will strip adjacent empty lines and quotations.
8603 The character set of the terminal \*(UA operates on,
8604 and the one and only supported character set that \*(UA can use if no
8605 character set conversion capabilities have been compiled into it,
8606 in which case it defaults to ISO-8859-1 unless it can deduce a value
8610 Refer to the section
8611 .Sx "Character sets"
8612 for the complete picture about character sets.
8616 For a safety-by-default policy \*(UA sets its process
8620 but this variable can be used to override that:
8621 set it to an empty value to don't change the (current) setting,
8622 otherwise the process file mode creation mask is updated to the new value.
8623 Child processes inherit the process file mode creation mask.
8626 .It Va user-HOST , user
8627 \*(IN Variable chain that sets a global fallback user name, which is
8628 used in case none has been given in the protocol and account-specific
8630 This variable defaults to the name of the user who runs \*(UA.
8634 \*(BO Setting this option enables upward compatibility with \*(UA
8635 version 15.0 in respect to which configuration options are available and
8636 how they are handled.
8637 This manual uses \*(IN and \*(OU to refer to the new and the old way of
8638 doing things, respectively.
8642 \*(BO Setting this option, also controllable via the command line option
8644 causes \*(UA to be more verbose, e.g., it will display obsoletion
8645 warnings and SSL/TLS certificate chains.
8646 Even though marked \*(BO this option may be set twice in order to
8647 increase the level of verbosity even more, in which case even details of
8648 the actual message delivery and protocol conversations are shown.
8651 is sufficient to disable verbosity as such.
8657 .It Va version , version-major , version-minor , version-update
8658 \*(RO \*(UA version information: the first variable contains a string
8659 containing the complete version identification \(en this is identical to
8660 the output of the command
8662 The latter three contain only digits: the major, minor and update
8666 .It Va writebackedited
8667 If this variable is set messages modified using the
8671 commands are written back to the current folder when it is quit;
8672 it is only honoured for writable folders in MBOX format, though.
8673 Note that the editor will be pointed to the raw message content in that
8674 case, i.e., neither MIME decoding nor decryption will have been
8675 performed, and proper RFC 4155
8677 quoting of newly added or edited content is also left as an excercise to
8681 .\" }}} (INTERNAL VARIABLES)
8684 .\" .Sh ENVIRONMENT {{{
8688 .Dq environment variable
8689 should be considered an indication that these variables are either
8690 standardized as vivid parts of process environments, or that they are
8691 commonly found in there.
8692 The process environment is inherited from the
8694 once \*(UA is started, and unless otherwise explicitly noted handling of
8695 the following variables transparently integrates into that of the
8696 .Sx "INTERNAL VARIABLES"
8697 from \*(UA's point of view.
8698 This means that, e.g., they can be managed via
8702 causing automatic program environment updates (to be inherited by
8703 newly created child processes).
8706 In order to transparently integrate other environment variables equally
8707 they need to be imported (linked) with the command
8709 This command can also be used to set and unset non-integrated
8710 environment variables from scratch, sufficient system support provided.
8711 The following example, applicable to a POSIX shell, sets the
8713 environment variable for \*(UA only, and beforehand exports the
8715 in order to affect any further processing in the running shell:
8717 .Bd -literal -offset indent
8718 $ EDITOR="vim -u ${HOME}/.vimrc"
8720 $ COLUMNS=80 \*(uA -R
8723 .Bl -tag -width ".It Ev _AILR_"
8726 The user's preferred width in column positions for the terminal screen
8728 Queried and used once on program startup, actively managed for child
8729 processes and the MLE (see
8730 .Sx "On terminal control and line editor" )
8731 in interactive mode thereafter.
8735 The name of the (mailbox)
8737 to use for saving aborted messages if
8739 is set; this defaults to
8746 is set no output will be generated, otherwise the contents of the file
8751 Pathname of the text editor to use in the
8755 .Sx "TILDE ESCAPES" .
8756 A default editor is used if this value is not defined.
8760 The user's home directory.
8761 This variable is only used when it resides in the process environment.
8768 .It Ev LANG , LC_ALL , LC_COLLATE , LC_CTYPE , LC_MESSAGES
8772 .Sx "Character sets" .
8773 (Only recognized by the system in the process environment.)
8777 The user's preferred number of lines on a page or the vertical screen
8778 or window size in lines.
8779 Queried and used once on program startup, actively managed for child
8780 processes in interactive mode thereafter.
8784 Pathname of the directory lister to use in the
8786 command when operating on local mailboxes.
8789 (path search through
8794 Upon startup \*(UA will actively ensure that this variable refers to the
8795 name of the user who runs \*(UA, in order to be able to pass a verified
8796 name to any newly created child process.
8800 Is used as the user's primary system mailbox, if set.
8801 Otherwise, a system-dependent default is used.
8802 Supports the special syntax conventions that are documented for the
8808 \*(OP Overrides the default path search for
8809 .Sx "The Mailcap files" ,
8810 which is defined in the standard RFC 1524 as
8811 .Ql ~/.mailcap:\:/etc/mailcap:\:/usr/etc/mailcap:\:/usr/local/etc/mailcap .
8812 .\" TODO we should have a mailcaps-default virtual RDONLY option!
8813 (\*(UA makes it a configuration option, however.)
8814 Note this is not a search path, but a path search.
8818 Is used as a startup file instead of
8821 When \*(UA scripts are invoked on behalf of other users,
8822 either this variable should be set to
8826 command line option should be used in order to avoid side-effects from
8827 reading their configuration files.
8828 This variable is only used when it resides in the process environment.
8832 The name of the user's mbox file.
8833 A logical subset of the special conventions that are documented for the
8838 The fallback default is
8843 Traditionally this secondary mailbox is used as the file to save
8844 messages from the primary system mailbox that have been read.
8846 .Sx "Message states" .
8849 .It Ev NAIL_NO_SYSTEM_RC
8850 If this variable is set then reading of
8852 at startup is inhibited, i.e., the same effect is achieved as if \*(UA
8853 had been started up with the option
8855 This variable is only used when it resides in the process environment.
8859 \*(IN\*(OP This variable overrides the default location of the user's
8865 Pathname of the program to use for backing the command
8869 variable enforces usage of a pager for output.
8870 The default paginator is
8872 (path search through
8875 \*(UA inspects the contents of this variable: if its contains the string
8877 then a non-existing environment variable
8884 dependent on whether terminal control support is available and whether
8885 that supports full (alternative) screen mode or not (also see
8886 .Sx "On terminal control and line editor" ) .
8890 will optionally be set to
8897 A list of directories that is searched by the shell when looking for
8898 commands (as such only recognized in the process environment).
8902 The shell to use for the commands
8908 and when starting subprocesses.
8909 A default shell is used if this option is not defined.
8912 .It Ev SOURCE_DATE_EPOCH
8913 If set, this specifies a time in seconds since the Unix epoch
8914 (1970-01-01) to be used in place of the current time.
8915 This is for the sake of reproduceability of tests, to be used during
8916 development or by software packagers.
8920 \*(OP The terminal type for which output is to be prepared.
8921 For extended colour and font control please refer to
8922 .Sx "Coloured display" ,
8923 and for terminal management in general to
8924 .Sx "On terminal control and line editor" .
8928 Used as directory for temporary files instead of
8931 This variable is only used when it resides in the process environment.
8937 (see there), but this variable is not standardized, should therefore not
8938 be used, and is only corrected if already set.
8942 Pathname of the text editor to use in the
8946 .Sx "TILDE ESCAPES" .
8954 .Bl -tag -width ".It Pa _etc/mime.type_"
8956 File giving initial commands.
8959 System wide initialization file.
8963 \*(OP Personal MIME type handler definition file, see
8964 .Sx "The Mailcap files" .
8965 (RFC 1524 location, the actual path is a configuration option.)
8969 \*(OP System wide MIME type handler definition file, see
8970 .Sx "The Mailcap files" .
8971 (RFC 1524 location, the actual path is a configuration option.)
8974 .It Pa ~/.mime.types
8975 Personal MIME types, see
8976 .Sx "The mime.types files" .
8979 .It Pa /etc/mime.types
8980 System wide MIME types, see
8981 .Sx "The mime.types files" .
8985 \*(IN\*(OP The default location of the users
8987 file \(en the section
8988 .Sx "The .netrc file"
8989 documents the file format.
8992 .\" .Ss "The mime.types files" {{{
8993 .Ss "The mime.types files"
8995 When sending messages \*(UA tries to determine the content type of all
8997 When displaying message content or attachments \*(UA uses the content
8998 type to decide whether it can directly display data or whether it needs
8999 to deal with content handlers.
9000 It learns about MIME types and how to treat them by reading
9002 files, the loading of which can be controlled by setting the variable
9003 .Va mimetypes-load-control .
9006 can also be used to deal with MIME types.)
9008 files have the following syntax:
9011 .Dl type/subtype extension [extension ...]
9016 are strings describing the file contents, and one or multiple
9018 s, separated by whitespace, name the part of a filename starting after
9019 the last dot (of interest).
9020 Comments may be introduced anywhere on a line with a number sign
9022 causing the remaining line to be discarded.
9024 \*(UA also supports an extended, non-portable syntax in specially
9025 crafted files, which can be loaded via the alternative value syntax of
9026 .Va mimetypes-load-control
9027 and prepends an optional
9031 .Dl [type-marker ]type/subtype extension [extension ...]
9034 The following type markers are supported:
9037 .Bl -tag -compact -offset indent -width ".It Ar _n_u"
9039 Treat message parts with this content as plain text.
9044 Treat message parts with this content as HTML tagsoup.
9045 If the \*(OPal HTML-tagsoup-to-text converter is not available treat
9046 the content as plain text instead.
9050 but instead of falling back to plain text require an explicit content
9051 handler to be defined.
9056 for sending messages:
9058 .Va mime-allow-text-controls ,
9059 .Va mimetypes-load-control .
9060 For reading etc. messages:
9061 .Sx "HTML mail and MIME attachments" ,
9062 .Sx "The Mailcap files" ,
9064 .Va mime-counter-evidence ,
9065 .Va mimetypes-load-control ,
9066 .Va pipe-TYPE/SUBTYPE ,
9067 .Va pipe-EXTENSION .
9070 .\" .Ss "The Mailcap files" {{{
9071 .Ss "The Mailcap files"
9074 .Dq User Agent Configuration Mechanism
9075 which \*(UA \*(OPally supports.
9076 It defines a file format to be used to inform mail user agent programs
9077 about the locally-installed facilities for handling various data
9078 formats, i.e., about commands and how they can be used to display, edit
9079 etc. MIME part contents, as well as a default path search that includes
9080 multiple possible locations of
9084 environment variable that can be used to overwrite that (repeating here
9085 that it is not a search path, but instead a path search specification).
9086 Any existing files will be loaded in sequence, appending any content to
9087 the list of MIME type handler directives.
9091 files consist of a set of newline separated entries.
9092 Comment lines start with a number sign
9094 (in the first column!) and are ignored.
9095 Empty lines are also ignored.
9096 All other lines form individual entries that must adhere to the syntax
9098 To extend a single entry (not comment) its line can be continued on
9099 follow lines if newline characters are
9101 by preceding them with the reverse solidus character
9103 The standard doesn't specify how leading whitespace of follow lines is
9104 to be treated, therefore \*(UA retains it.
9108 entries consist of a number of semicolon
9110 separated fields, and the reverse solidus
9112 character can be used to escape any following character including
9113 semicolon and itself.
9114 The first two fields are mandatory and must occur in the specified
9115 order, the remaining fields are optional and may appear in any order.
9116 Leading and trailing whitespace of content is ignored (removed).
9119 The first field defines the MIME
9121 the entry is about to handle (case-insensitively, and no reverse solidus
9122 escaping is possible in this field).
9123 If the subtype is specified as an asterisk
9125 the entry is meant to match all subtypes of the named type, e.g.,
9127 would match any audio type.
9128 The second field defines the shell command which shall be used to
9130 MIME parts of the given type; it is implicitly called the
9137 shell commands message (MIME part) data is passed via standard input
9138 unless the given shell command includes one or more instances of the
9141 in which case these instances will be replaced with a temporary filename
9142 and the data will have been stored in the file that is being pointed to.
9145 shell commands data is assumed to be generated on standard output unless
9146 the given command includes (one ore multiple)
9148 In any case any given
9150 format is replaced with a(n already) properly quoted filename.
9151 Note that when a command makes use of a temporary file via
9153 then \*(UA will remove it again, as if the
9154 .Cd x-mailx-tmpfile ,
9155 .Cd x-mailx-tmpfile-fill
9157 .Cd x-mailx-tmpfile-unlink
9158 flags had been set; see below for more.
9161 The optional fields either define a shell command or an attribute (flag)
9162 value, the latter being a single word and the former being a keyword
9163 naming the field followed by an equals sign
9165 succeeded by a shell command, and as usual for any
9167 content any whitespace surrounding the equals sign will be removed, too.
9168 Optional fields include the following:
9171 .Bl -tag -width textualnewlines
9173 A program that can be used to compose a new body or body part in the
9180 field, but is to be used when the composing program needs to specify the
9182 header field to be applied to the composed data.
9186 A program that can be used to edit a body or body part in the given
9191 A program that can be used to print a message or body part in the given
9196 Specifies a program to be run to test some condition, e.g., the machine
9197 architecture, or the window system in use, to determine whether or not
9198 this mailcap entry applies.
9199 If the test fails, a subsequent mailcap entry should be sought; also see
9200 .Cd x-mailx-test-once .
9202 .It Cd needsterminal
9203 This flag field indicates that the given shell command must be run on
9204 an interactive terminal.
9205 \*(UA will temporarily release the terminal to the given command in
9206 interactive mode, in non-interactive mode this entry will be entirely
9207 ignored; this flag implies
9208 .Cd x-mailx-noquote .
9210 .It Cd copiousoutput
9211 A flag field which indicates that the output of the
9213 command will be an extended stream of textual output that can be
9214 (re)integrated into \*(UA's normal visual display.
9215 It is mutually exclusive with
9218 .Cd x-mailx-always .
9220 .It Cd textualnewlines
9221 A flag field which indicates that this type of data is line-oriented and
9224 all newlines should be converted to canonical form (CRLF) before
9225 encoding, and will be in that form after decoding.
9229 This field gives a file name format, in which
9231 will be replaced by a random string, the joined combination of which
9232 will be used as the filename denoted by
9233 .Ev NAIL_FILENAME_TEMPORARY .
9234 One could specify that a GIF file being passed to an image viewer should
9235 have a name ending in
9238 .Ql nametemplate=%s.gif .
9239 Note that \*(UA ignores the name template unless that solely specifies
9240 a filename suffix that consists of (ASCII) alphabetic and numeric
9241 characters, the underscore and dot only.
9244 Names a file, in X11 bitmap (xbm) format, which points to an appropriate
9245 icon to be used to visually denote the presence of this kind of data.
9246 This field is not used by \*(UA.
9249 A textual description that describes this type of data.
9251 .It Cd x-mailx-always
9252 Extension flag field that denotes that the given
9254 command shall be executed even if multiple messages will be displayed
9256 Normally messages which require external viewers that produce output
9257 which doesn't integrate into \*(UA's visual display (i.e., don't have
9259 set) have to be addressed directly and individually.
9260 (To avoid cases where, e.g., a thousand PDF viewer instances are spawned
9263 .It Cd x-mailx-even-if-not-interactive
9264 An extension flag test field \(em by default handlers without
9266 are entirely ignored in non-interactive mode, but if this flag is set
9267 then their use will be considered.
9268 It is an error if this flag is set for commands that use the flag
9271 .It Cd x-mailx-noquote
9272 An extension flag field that indicates that even a
9275 command shall not be used to generate message quotes
9276 (as it would be by default).
9278 .It Cd x-mailx-async
9279 Extension flag field that denotes that the given
9281 command shall be executed asynchronously, without blocking \*(UA.
9282 Cannot be used in conjunction with
9285 .It Cd x-mailx-test-once
9286 Extension flag which denotes whether the given
9288 command shall be evaluated once only and the (boolean) result be cached.
9289 This is handy if some global unchanging condition is to be queried, like
9290 .Dq running under the X Window System .
9292 .It Cd x-mailx-tmpfile
9293 Extension flag field that requests creation of a zero-sized temporary
9294 file, the name of which is to be placed in the environment variable
9295 .Ev NAIL_FILENAME_TEMPORARY .
9296 It is an error to use this flag with commands that include a
9300 .It Cd x-mailx-tmpfile-fill
9301 Normally the MIME part content is passed to the handler via standard
9302 input; if this flag is set then the data will instead be written into
9304 .Cd x-mailx-tmpfile .
9305 In order to cause deletion of the temporary file you will have to set
9306 .Cd x-mailx-tmpfile-unlink
9308 It is an error to use this flag with commands that include a
9312 .It Cd x-mailx-tmpfile-unlink
9313 Extension flag field that requests that the temporary file shall be
9314 deleted automatically when the command loop is entered again at latest.
9315 (Don't use this for asynchronous handlers.)
9316 It is an error to use this flag with commands that include a
9318 format, or without also setting
9321 .Cd x-mailx-tmpfile-fill .
9323 .It Cd x-mailx-tmpfile-keep
9326 implies the three tmpfile related flags above, but if you want, e.g.,
9328 and deal with the temporary file yourself, you can add in this flag to
9330 .Cd x-mailx-tmpfile-unlink .
9335 The standard includes the possibility to define any number of additional
9336 entry fields, prefixed by
9338 Flag fields apply to the entire
9340 entry \(em in some unusual cases, this may not be desirable, but
9341 differentiation can be accomplished via separate entries, taking
9342 advantage of the fact that subsequent entries are searched if an earlier
9343 one does not provide enough information.
9346 command needs to specify the
9350 command shall not, the following will help out the latter (with enabled
9354 level \*(UA will show information about handler evaluation):
9356 .Bd -literal -offset indent
9357 application/postscript; ps-to-terminal %s; needsterminal
9358 application/postscript; ps-to-terminal %s; compose=idraw %s
9362 In fields any occurrence of the format string
9364 will be replaced by the
9367 Named parameters from the
9369 field may be placed in the command execution line using
9371 followed by the parameter name and a closing
9374 The entire parameter should appear as a single command line argument,
9375 regardless of embedded spaces; thus:
9377 .Bd -literal -offset indent
9379 Content-type: multipart/mixed; boundary=42
9382 multipart/*; /usr/local/bin/showmulti \e
9383 %t %{boundary} ; composetyped = /usr/local/bin/makemulti
9385 # Executed shell command
9386 /usr/local/bin/showmulti multipart/mixed 42
9390 .\" TODO v15: Mailcap: %n,%F
9391 Note that \*(UA doesn't support handlers for multipart MIME parts as
9392 shown in this example (as of today).
9393 \*(UA doesn't support the additional formats
9397 An example file, also showing how to properly deal with the expansion of
9399 which includes any quotes that are necessary to make it a valid shell
9400 argument by itself and thus will cause undesired behaviour when placed
9401 in additional user-provided quotes:
9403 .Bd -literal -offset indent
9405 text/richtext; richtext %s; copiousoutput
9407 text/x-perl; perl -cWT %s
9411 trap "rm -f ${infile}" EXIT\e; \e
9412 trap "exit 75" INT QUIT TERM\e; \e
9414 x-mailx-async; x-mailx-tmpfile-keep
9416 application/*; echo "This is \e"%t\e" but \e
9417 is 50 \e% Greek to me" \e; < %s head -c 1024 | cat -vET; \e
9418 copiousoutput; x-mailx-noquote
9423 .Sx "HTML mail and MIME attachments" ,
9424 .Sx "The mime.types files" ,
9427 .Va mime-counter-evidence ,
9428 .Va pipe-TYPE/SUBTYPE ,
9429 .Va pipe-EXTENSION .
9432 .\" .Ss "The .netrc file" {{{
9433 .Ss "The .netrc file"
9437 file contains user credentials for machine accounts.
9438 The default location in the user's
9440 directory may be overridden by the
9442 environment variable.
9443 The file consists of space, tabulator or newline separated tokens.
9444 \*(UA implements a parser that supports a superset of the original BSD
9445 syntax, but users should nonetheless be aware of portability glitches
9446 of that file format, shall their
9448 be usable across multiple programs and platforms:
9451 .Bl -bullet -compact
9453 BSD doesn't support single, but only double quotation marks, e.g.,
9454 .Ql password="pass with spaces" .
9456 BSD (only?) supports escaping of single characters via a reverse solidus
9457 (e.g., a space can be escaped via
9459 in- as well as outside of a quoted string.
9461 BSD doesn't require the final quotation mark of the final user input token.
9463 The original BSD (Berknet) parser also supported a format which allowed
9464 tokens to be separated with commas \(en whereas at least Hewlett-Packard
9465 still seems to support this syntax, \*(UA does not!
9467 As a non-portable extension some widely-used programs support
9468 shell-style comments: if an input line starts, after any amount of
9469 whitespace, with a number sign
9471 then the rest of the line is ignored.
9473 Whereas other programs may require that the
9475 file is accessible by only the user if it contains a
9481 \*(UA will always require these strict permissions.
9485 Of the following list of supported tokens \*(UA only uses (and caches)
9490 At runtime the command
9492 can be used to control \*(UA's
9496 .Bl -tag -width password
9497 .It Cd machine Ar name
9498 The hostname of the entries' machine, lowercase-normalized by \*(UA
9500 Any further file content, until either end-of-file or the occurrence
9505 first-class token is bound (only related) to the machine
9508 As an extension that shouldn't be the cause of any worries
9509 \*(UA supports a single wildcard prefix for
9511 .Bd -literal -offset indent
9512 machine *.example.com login USER password PASS
9513 machine pop3.example.com login USER password PASS
9514 machine smtp.example.com login USER password PASS
9520 .Ql pop3.example.com ,
9524 .Ql local.smtp.example.com .
9525 Note that in the example neither
9526 .Ql pop3.example.com
9528 .Ql smtp.example.com
9529 will be matched by the wildcard, since the exact matches take
9530 precedence (it is however faster to specify it the other way around).
9535 except that it is a fallback entry that is used shall none of the
9536 specified machines match; only one default token may be specified,
9537 and it must be the last first-class token.
9539 .It Cd login Ar name
9540 The user name on the remote machine.
9542 .It Cd password Ar string
9543 The user's password on the remote machine.
9545 .It Cd account Ar string
9546 Supply an additional account password.
9547 This is merely for FTP purposes.
9549 .It Cd macdef Ar name
9551 A macro is defined with the specified
9553 it is formed from all lines beginning with the next line and continuing
9554 until a blank line is (consecutive newline characters are) encountered.
9557 entries cannot be utilized by multiple machines, too, but must be
9558 defined following the
9560 they are intended to be used with.)
9563 exists, it is automatically run as the last step of the login process.
9564 This is merely for FTP purposes.
9571 .\" .Sh EXAMPLES {{{
9574 .\" .Ss "An example configuration" {{{
9575 .Ss "An example configuration"
9577 .Bd -literal -offset indent
9578 # This example assumes v15.0 compatibility mode
9581 # Where are the up-to-date SSL certificates?
9582 #set ssl-ca-dir=/etc/ssl/certs
9583 set ssl-ca-file=/etc/ssl/certs/ca-certificates.crt
9585 # (Since we manage up-to-date ones explicitly, don't use any,
9586 # possibly outdated, default certificates shipped with OpenSSL)
9587 set ssl-no-default-ca
9589 # Don't use protocols older than TLS v1.2.
9590 # Change this only when the remote server doesn't support it:
9591 # maybe use ssl-protocol-HOST (or -USER@HOST) syntax to define
9592 # such explicit exceptions, then
9593 set ssl-protocol='-ALL,+TLSv1.2'
9595 # Explicitly define the list of ciphers, which may improve security,
9596 # especially with protocols older than TLS v1.2. See ciphers(1).
9597 # Including "@STRENGTH" will sort the final list by algorithm strength.
9598 # In reality it is possibly best to only use ssl-cipher-list-HOST
9599 # (or -USER@HOST), as necessary, again..
9600 set ssl-cipher-list=TLSv1.2:!aNULL:!eNULL:!MEDIUM:!LOW:!EXPORT:@STRENGTH
9601 # ALL:!aNULL:!MEDIUM:!LOW:!MD5:!RC4:!EXPORT:@STRENGTH
9603 # Request strict transport security checks!
9604 set ssl-verify=strict
9606 # Essential setting: select allowed character sets
9607 set sendcharsets=utf-8,iso-8859-1
9609 # A very kind option: when replying to a message, first try to
9610 # use the same encoding that the original poster used herself!
9611 set reply-in-same-charset
9613 # When replying to or forwarding a message the comment and name
9614 # parts of email addresses are removed unless this variable is set
9617 # When sending messages, wait until the Mail-Transfer-Agent finishs.
9618 # Only like this you'll be able to see errors reported through the
9619 # exit status of the MTA (including the builtin SMTP one)!
9622 # Only use builtin MIME types, no mime.types(5) files
9623 set mimetypes-load-control
9625 # Default directory where we act in (relative to $HOME)
9627 # A leading "+" (often) means: under *folder*
9628 # *record* is used to save copies of sent messages
9629 set MBOX=+mbox.mbox record=+sent.mbox DEAD=+dead.txt
9631 # Make "file mymbox" and "file myrec" go to..
9632 shortcut mymbox %:+mbox.mbox myrec +sent.mbox
9634 # Not really optional, e.g., for S/MIME
9635 set from='Your Name <address@exam.ple>'
9637 # It may be necessary to set hostname and/or smtp-hostname
9638 # if the "SERVER" of mta and "domain" of from don't match.
9639 # The `urlencode' command can be used to encode USER and PASS
9640 set mta=(smtps?|submission)://[USER[:PASS]@]SERVER[:PORT] \e
9641 smtp-auth=login/plain... \e
9644 # Never refuse to start into interactive mode, and more
9646 colour-pager crt= \e
9647 followup-to followup-to-honour=ask-yes \e
9648 history-file=+.\*(uAhist history-size=-1 history-gabby \e
9649 mime-counter-evidence=0xE \e
9650 prompt='?\e?[\e$ \e@]\e& ' \e
9651 reply-to-honour=ask-yes \e
9654 # When `t'yping messages, show only these headers
9655 # (use `T'ype for all headers and `S'how for raw message)
9656 retain date from to cc subject
9658 # Some mailing lists
9659 mlist '@xyz-editor\e.xyz$' '@xyzf\e.xyz$'
9660 mlsubscribe '^xfans@xfans\e.xyz$'
9662 # A real life example of a very huge free mail provider
9664 set folder=~/spool/XooglX MAIL=+syste.mbox sent=+sent
9665 set from='Your Name <address@examp.ple>'
9666 set mta=smtp://USER:PASS@smtp.gmXil.com smtp-use-starttls
9669 # Here is a pretty large one which does not allow sending mails
9670 # if there is a domain name mismatch on the SMTP protocol level,
9671 # which would bite us if the value of from does not match, e.g.,
9672 # for people who have a sXXXXeforge project and want to speak
9673 # with the mailing list under their project account (in from),
9674 # still sending the message through their normal mail provider
9676 set folder=~/spool/XandeX MAIL=+syste.mbox sent=+sent
9677 set from='Your Name <address@exam.ple>'
9678 set mta=smtps://USER:PASS@smtp.yaXXex.ru:465 \e
9679 hostname=yaXXex.com smtp-hostname=
9682 # Create some new commands so that, e.g., `ls /tmp' will..
9683 wysh ghost lls '!ls ${LS_COLOR_FLAG} -aFlrS'
9684 wysh ghost llS '!ls ${LS_COLOR_FLAG} -aFlS'
9685 wysh ghost ls '!ls ${LS_COLOR_FLAG} -aFrS'
9686 wysh ghost lS '!ls ${LS_COLOR_FLAG} -aFS'
9687 wysh ghost lla '!ls ${LS_COLOR_FLAG} -aFlr'
9688 wysh ghost llA '!ls ${LS_COLOR_FLAG} -aFl'
9689 wysh ghost la '!ls ${LS_COLOR_FLAG} -aFr'
9690 wysh ghost lA '!ls ${LS_COLOR_FLAG} -aF'
9691 wysh ghost ll '!ls ${LS_COLOR_FLAG} -aFltr'
9692 wysh ghost lL '!ls ${LS_COLOR_FLAG} -aFlt'
9693 wysh ghost l '!ls ${LS_COLOR_FLAG} -aFtr'
9694 wysh ghost L '!ls ${LS_COLOR_FLAG} -aFt'
9696 # We don't support gpg(1) directly yet. But simple --clearsign'd
9697 # message parts can be dealt with as follows:
9699 wysh set pipe-text/plain=$'@*#++=@\e
9700 < "${NAIL_FILENAME_TEMPORARY}" awk \e
9701 -v TMPFILE="${NAIL_FILENAME_TEMPORARY}" \e'\e
9703 /^-----BEGIN PGP SIGNED MESSAGE-----/,/^$/{\e
9706 print "--- GPG --verify ---";\e
9707 system("gpg --verify " TMPFILE " 2>&1");\e
9708 print "--- GPG --verify ---";\e
9712 /^-----BEGIN PGP SIGNATURE-----/,\e
9713 /^-----END PGP SIGNATURE-----/{\e
9723 !printf 'Key IDs to gpg --recv-keys: ';\e
9725 gpg --recv-keys ${keyids};
9731 When storing passwords in
9733 appropriate permissions should be set on this file with
9734 .Ql $ chmod 0600 \*(ur .
9737 is available user credentials can be stored in the central
9739 file instead; e.g., here is a different version of the example account
9740 that sets up SMTP and POP3:
9742 .Bd -literal -offset indent
9744 set folder=~/spool/XandeX MAIL=+syste.mbox sent=+sent
9745 set from='Your Name <address@exam.ple>'
9747 # Load an encrypted ~/.netrc by uncommenting the next line
9748 #set netrc-pipe='gpg -qd ~/.netrc.pgp'
9750 set mta=smtps://smtp.yXXXXx.ru:465 \e
9751 smtp-hostname= hostname=yXXXXx.com
9752 set pop3-keepalive=240 pop3-no-apop-pop.yXXXXx.ru
9753 ghost xp fi pop3s://pop.yXXXXx.ru
9762 .Bd -literal -offset indent
9763 machine *.yXXXXx.ru login USER password PASS
9767 This configuration should now work just fine:
9770 .Dl $ echo text | \*(uA -vv -AXandeX -s Subject user@exam.ple
9773 .\" .Ss "Signed and encrypted messages with S/MIME" {{{
9774 .Ss "Signed and encrypted messages with S/MIME"
9776 \*(OP S/MIME provides two central mechanisms:
9777 message signing and message encryption.
9778 A signed message contains some data in addition to the regular text.
9779 The data can be used to verify that the message was sent using a valid
9780 certificate, that the sender's address in the message header matches
9781 that in the certificate, and that the message text has not been altered.
9782 Signing a message does not change its regular text;
9783 it can be read regardless of whether the recipient's software is able to
9787 It is thus usually possible to sign all outgoing messages if so desired.
9788 Encryption, in contrast, makes the message text invisible for all people
9789 except those who have access to the secret decryption key.
9790 To encrypt a message, the specific recipient's public encryption key
9792 It is therefore not possible to send encrypted mail to people unless their
9793 key has been retrieved from either previous communication or public key
9795 A message should always be signed before it is encrypted.
9796 Otherwise, it is still possible that the encrypted message text is
9800 A central concept to S/MIME is that of the certification authority (CA).
9801 A CA is a trusted institution that issues certificates.
9802 For each of these certificates it can be verified that it really
9803 originates from the CA, provided that the CA's own certificate is
9805 A set of CA certificates is usually delivered with OpenSSL and installed
9807 If you trust the source of your OpenSSL software installation,
9808 this offers reasonable security for S/MIME on the Internet.
9810 .Va ssl-no-default-ca
9814 .Va smime-ca-dir . )
9815 In general, a certificate cannot be more secure than the method its CA
9816 certificate has been retrieved with, though.
9817 Thus if you download a CA certificate from the Internet,
9818 you can only trust the messages you verify using that certificate as
9819 much as you trust the download process.
9822 The first thing you need for participating in S/MIME message exchange is
9823 your personal certificate, including a private key.
9824 The certificate contains public information, in particular your name and
9825 your email address(es), and the public key that is used by others to
9826 encrypt messages for you,
9827 and to verify signed messages they supposedly received from you.
9828 The certificate is included in each signed message you send.
9829 The private key must be kept secret.
9830 It is used to decrypt messages that were previously encrypted with your
9831 public key, and to sign messages.
9834 For personal use it is recommended that you get a S/MIME certificate
9835 from one of the major CAs on the Internet using your WWW browser.
9836 Many CAs offer such certificates for free.
9838 .Lk https://www.CAcert.org
9839 which issues client and server certificates to members of their
9840 community for free; their root certificate
9841 .Pf ( Lk https://\:www.cacert.org/\:certs/\:root.crt )
9842 is often not in the default set of trusted CA root certificates, though,
9843 which means you will have to download their root certificate separately
9844 and ensure it is part of our S/MIME certificate validation chain by
9847 or as a vivid member of the
9849 But let's take a step-by-step tour on how to setup S/MIME with
9850 a certificate from CAcert.org despite this situation!
9853 First of all you will have to become a member of the CAcert.org
9854 community, simply by registrating yourself via the web interface.
9855 Once you are, create and verify all email addresses you want to be able
9856 to create signed and encrypted messages for/with using the corresponding
9857 entries of the web interface.
9858 Now ready to create S/MIME certificates, so let's create a new
9859 .Dq client certificate ,
9860 ensure to include all email addresses that should be covered by the
9861 certificate in the following web form, and also to use your name as the
9865 Create a private key and a certificate request on your local computer
9866 (please see the manual pages of the used commands for more in-depth
9867 knowledge on what the used arguments etc. do):
9870 .Dl openssl req -nodes -newkey rsa:4096 -keyout key.pem -out creq.pem
9873 Afterwards copy-and-paste the content of
9875 into the certificate-request (CSR) field of the web form on the
9876 CAcert.org website (you may need to unfold some
9877 .Dq advanced options
9878 to see the corresponding text field).
9879 This last step will ensure that your private key (which never left your
9880 box) and the certificate belong together (through the public key that
9881 will find its way into the certificate via the certificate-request).
9882 You are now ready and can create your CAcert certified certificate.
9883 Download and store or copy-and-paste it as
9888 In order to use your new S/MIME setup you will have to create
9889 a combined private key/public key (certificate) file:
9892 .Dl cat key.pem pub.crt > ME@HERE.com.paired
9895 This is the file \*(UA will work with.
9896 If you have created your private key with a passphrase then \*(UA will
9897 ask you for it whenever a message is signed or decrypted.
9898 Set the following variables to henceforth use S/MIME (setting
9900 is of interest for verification only):
9902 .Bd -literal -offset indent
9903 set smime-ca-file=ALL-TRUSTED-ROOT-CERTS-HERE \e
9904 smime-sign-cert=ME@HERE.com.paired \e
9905 smime-sign-message-digest=SHA256 \e
9910 From each signed message you send, the recipient can fetch your
9911 certificate and use it to send encrypted mail back to you.
9912 Accordingly if somebody sends you a signed message, you can do the same,
9915 command to check the validity of the certificate.
9918 Variables of interest for S/MIME signing:
9922 .Va smime-crl-file ,
9923 .Va smime-no-default-ca ,
9925 .Va smime-sign-cert ,
9926 .Va smime-sign-include-certs
9928 .Va smime-sign-message-digest .
9931 After it has been verified save the certificate via
9933 and tell \*(UA that it should use it for encryption for further
9934 communication with that somebody:
9936 .Bd -literal -offset indent
9938 set smime-encrypt-USER@HOST=FILENAME \e
9939 smime-cipher-USER@HOST=AES256
9943 Additional variables of interest for S/MIME en- and decryption:
9946 .Va smime-encrypt-USER@HOST .
9949 You should carefully consider if you prefer to store encrypted messages
9951 If you do, anybody who has access to your mail folders can read them,
9952 but if you do not, you might be unable to read them yourself later if
9953 you happen to lose your private key.
9956 command saves messages in decrypted form, while the
9960 commands leave them encrypted.
9963 Note that neither S/MIME signing nor encryption applies to message
9964 subjects or other header fields yet.
9965 Thus they may not contain sensitive information for encrypted messages,
9966 and cannot be trusted even if the message content has been verified.
9967 When sending signed messages,
9968 it is recommended to repeat any important header information in the
9972 .\" .Ss "Using CRLs with S/MIME or SSL/TLS" {{{
9973 .Ss "Using CRLs with S/MIME or SSL/TLS"
9975 \*(OP Certification authorities (CAs) issue certificate revocation
9976 lists (CRLs) on a regular basis.
9977 These lists contain the serial numbers of certificates that have been
9978 declared invalid after they have been issued.
9979 Such usually happens because the private key for the certificate has
9981 because the owner of the certificate has left the organization that is
9982 mentioned in the certificate, etc.
9983 To seriously use S/MIME or SSL/TLS verification,
9984 an up-to-date CRL is required for each trusted CA.
9985 There is otherwise no method to distinguish between valid and
9986 invalidated certificates.
9987 \*(UA currently offers no mechanism to fetch CRLs, nor to access them on
9988 the Internet, so you have to retrieve them by some external mechanism.
9991 \*(UA accepts CRLs in PEM format only;
9992 CRLs in DER format must be converted, like, e.\|g.:
9995 .Dl $ openssl crl \-inform DER \-in crl.der \-out crl.pem
9998 To tell \*(UA about the CRLs, a directory that contains all CRL files
9999 (and no other files) must be created.
10004 variables, respectively, must then be set to point to that directory.
10005 After that, \*(UA requires a CRL to be present for each CA that is used
10006 to verify a certificate.
10009 .\" .Ss "Handling spam" {{{
10010 .Ss "Handling spam"
10012 \*(OP \*(UA can make use of several spam interfaces for the purpose of
10013 identification of, and, in general, dealing with spam messages.
10014 A precondition of most commands in order to function is that the
10016 variable is set to one of the supported interfaces.
10017 Once messages have been identified as spam their (volatile)
10019 state can be prompted: the
10023 message specifications will address respective messages and their
10025 entries will be used when displaying the
10027 in the header display.
10032 rates the given messages and sets their
10035 If the spam interface offers spam scores those can also be displayed in
10036 the header display by including the
10046 will interact with the Bayesian filter of the chosen interface and learn
10047 the given messages as
10051 respectively; the last command can be used to cause
10053 of messages; it adheres to their current
10055 state and thus reverts previous teachings.
10060 will simply set and clear, respectively, the mentioned volatile
10062 message flag, without any interface interaction.
10071 requires a running instance of the
10073 server in order to function, started with the option
10075 shall Bayesian filter learning be possible.
10077 .Bd -literal -offset indent
10078 $ spamd -i localhost:2142 -i /tmp/.spamsock -d [-L] [-l]
10079 $ spamd --listen=localhost:2142 --listen=/tmp/.spamsock \e
10080 --daemonize [--local] [--allow-tell]
10084 Thereafter \*(UA can make use of these interfaces:
10086 .Bd -literal -offset indent
10087 $ \*(uA -Sspam-interface=spamc -Sspam-maxsize=500000 \e
10088 -Sspamc-command=/usr/local/bin/spamc \e
10089 -Sspamc-arguments="-U /tmp/.spamsock" -Sspamc-user=
10091 $ \*(uA -Sspam-interface=spamc -Sspam-maxsize=500000 \e
10092 -Sspamc-command=/usr/local/bin/spamc \e
10093 -Sspamc-arguments="-d localhost -p 2142" -Sspamc-user=
10097 Using the generic filter approach allows usage of programs like
10099 Here is an example, requiring it to be accessible via
10102 .Bd -literal -offset indent
10103 $ \*(uA -Sspam-interface=filter -Sspam-maxsize=500000 \e
10104 -Sspamfilter-ham="bogofilter -n" \e
10105 -Sspamfilter-noham="bogofilter -N" \e
10106 -Sspamfilter-nospam="bogofilter -S" \e
10107 -Sspamfilter-rate="bogofilter -TTu 2>/dev/null" \e
10108 -Sspamfilter-spam="bogofilter -s" \e
10109 -Sspamfilter-rate-scanscore="1;^(.+)$"
10113 Because messages must exist on local storage in order to be scored (or
10114 used for Bayesian filter training), it is possibly a good idea to
10115 perform the local spam check last:
10117 .Bd -literal -offset indent
10118 define spamdelhook {
10120 spamset (header x-dcc-brand-metrics "bulk")
10121 # Server-side spamassassin(1)
10122 spamset (header x-spam-flag "YES")
10123 del :s # TODO we HAVE to be able to do `spamrate :u ! :sS'
10124 move :S +maybe-spam
10127 move :S +maybe-spam
10129 set folder-hook-FOLDER=spamdelhook
10133 See also the documentation for the variables
10134 .Va spam-interface , spam-maxsize ,
10135 .Va spamc-command , spamc-arguments , spamc-user ,
10136 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
10139 .Va spamfilter-rate-scanscore .
10147 In general it is a good idea to turn on
10153 twice) if something doesn't work well.
10154 Very often a diagnostic message can be produced that leads to the
10155 problems' solution.
10157 .\" .Ss "\*(UA shortly hangs on startup" {{{
10158 .Ss "\*(UA shortly hangs on startup"
10160 This can have two reasons, one is the necessity to wait for a file lock
10161 and can't be helped, the other being that \*(UA calls the function
10163 in order to query the nodename of the box (sometimes the real one is
10164 needed instead of the one represented by the internal variable
10166 You may have varying success by ensuring that the real hostname and
10170 or, more generally, that the name service is properly setup \(en
10173 return what you'd expect?
10174 Does this local hostname has a domain suffix?
10175 RFC 6762 standardized the link-local top-level domain
10179 .\" .Ss "I can't login to Google mail aka GMail" {{{
10180 .Ss "I can't login to Google mail aka GMail"
10182 Since 2014 some free service providers classify programs as
10184 unless they use a special authentification method (OAuth 2.0) which
10185 wasn't standardized for non-HTTP protocol authentication token query
10186 until August 2015 (RFC 7628).
10189 Different to Kerberos / GSSAPI, which is developed since the mid of the
10190 1980s, where a user can easily create a local authentication ticket for
10191 her- and himself with the locally installed
10193 program, that protocol has no such local part but instead requires
10194 a world-wide-web query to create or fetch a token; since there is no
10195 local cache this query has to be performed whenever \*(UA is invoked
10196 from the command line (in interactive sessions situation may differ).
10199 \*(UA doesn't support OAuth.
10200 Because of this it is necessary to declare \*(UA a
10201 .Dq less secure app
10202 (on the providers account web page) in order to read and send mail.
10203 However, it also seems possible to take the following steps instead:
10208 give the provider the number of a mobile phone,
10211 .Dq 2-Step Verification ,
10213 create an application specific password (16 characters), and
10215 use that special password instead of your real Google account password in
10216 \*(UA (for more on that see the section
10217 .Sx "On URL syntax and credential lookup" ) .
10221 .\" .Ss "Not \(dqdefunctional\(dq, but the editor key won't work" {{{
10222 .Ss "Not \(dqdefunctional\(dq, but the editor key won't work"
10224 It can happen that the terminal library (see
10225 .Sx "On terminal control and line editor",
10228 reports different codes than the terminal really sends, in which case
10229 \*(UA will tell that a key binding is functional, but won't be able to
10230 recognize it because the received data doesn't match anything expected.
10231 The verbose listing of
10233 ings will show the byte sequences that are expected.
10236 To overcome the situation, use, e.g., the program
10238 in conjunction with the
10240 flag if available, to see the byte sequences which are actually produced
10241 by keypresses, and use the variable
10243 to make \*(UA aware of them.
10244 E.g., the terminal this is typed on produces some false sequences, here
10245 an example showing the shifted home key:
10247 .Bd -literal -offset indent
10250 # 1B 5B=[ 31=1 3B=; 32=2 48=H
10255 ? \*(uA -v -Stermcap='kHOM=\eE[H'
10264 .\" .Sh "SEE ALSO" {{{
10274 .Xr spamassassin 1 ,
10283 .Xr mailwrapper 8 ,
10288 .\" .Sh HISTORY {{{
10291 M. Douglas McIlroy writes in his article
10292 .Dq A Research UNIX Reader: Annotated Excerpts \
10293 from the Programmer's Manual, 1971-1986
10296 command already appeared in First Edition
10300 .Bd -ragged -offset indent
10301 Electronic mail was there from the start.
10302 Never satisfied with its exact behavior, everybody touched it at one
10303 time or another: to assure the safety of simultaneous access, to improve
10304 privacy, to survive crashes, to exploit uucp, to screen out foreign
10305 freeloaders, or whatever.
10306 Not until v7 did the interface change (Thompson).
10307 Later, as mail became global in its reach, Dave Presotto took charge and
10308 brought order to communications with a grab-bag of external networks
10314 Mail was written in 1978 by Kurt Shoens and developed as part of the
10317 distribution until 1995.
10318 Mail has then seen further development in open source
10320 variants, noticeably by Christos Zoulas in
10322 Basing upon this Nail, later Heirloom Mailx, was developed by Gunnar
10323 Ritter in the years 2000 until 2008.
10324 Since 2012 S-nail is maintained by Steffen (Daode) Nurpmeso.
10325 This man page is derived from
10326 .Dq The Mail Reference Manual
10327 that was originally written by Kurt Shoens.
10333 .An "Kurt Shoens" ,
10334 .An "Edward Wang" ,
10335 .An "Keith Bostic" ,
10336 .An "Christos Zoulas" ,
10337 .An "Gunnar Ritter" ,
10338 .An "Steffen Nurpmeso" Aq Mt s-nail-users@lists.sourceforge.net
10340 .Mt s-mailx@sdaoden.eu ) .
10343 .\" .Sh CAVEATS {{{
10346 \*(ID Interrupting an operation via
10350 is often problematic: many library functions cannot deal with the
10352 that this software (still) performs.
10355 The SMTP and POP3 protocol support of \*(UA is very basic.
10356 Also, if it fails to contact its upstream SMTP server, it will not make
10357 further attempts to transfer the message at a later time (setting
10362 If this is a concern, it might be better to set up a local SMTP server
10363 that is capable of message queuing.
10369 After deleting some message of a POP3 mailbox the header summary falsely
10370 claims that there are no messages to display, you need to perform
10371 a scroll or dot movement to restore proper state.
10373 In threaded display a power user may encounter crashes very
10374 occasionally (this is may and very).
10378 in the source repository lists future directions.