1 .\"@ nail.1 - S-nail(1) reference manual.
3 .\" Copyright (c) 1980, 1990, 1993
4 .\" The Regents of the University of California. All rights reserved.
6 .\" Gunnar Ritter. All rights reserved.
7 .\" Copyright (c) 2012 - 2015 Steffen (Daode) Nurpmeso <sdaoden@users.sf.net>.
9 .\" Redistribution and use in source and binary forms, with or without
10 .\" modification, are permitted provided that the following conditions
12 .\" 1. Redistributions of source code must retain the above copyright
13 .\" notice, this list of conditions and the following disclaimer.
14 .\" 2. Redistributions in binary form must reproduce the above copyright
15 .\" notice, this list of conditions and the following disclaimer in the
16 .\" documentation and/or other materials provided with the distribution.
17 .\" 3. All advertising materials mentioning features or use of this software
18 .\" must display the following acknowledgement:
19 .\" This product includes software developed by the University of
20 .\" California, Berkeley and its contributors.
21 .\" This product includes software developed by Gunnar Ritter
22 .\" and his contributors.
24 .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS 'AS IS' AND
25 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 .\" S-nail(1): v14.8.10 / 2016-08-20
49 .\" If not ~/.mailrc, it breaks POSIX compatibility. And adjust main.c.
54 .ds OU [no v15-compat]
55 .ds ID [v15 behaviour may differ]
56 .ds NQ [Only new quoting rules]
67 .Nd send and receive Internet mail
73 .\" Keep in SYNC: ./nail.1:"SYNOPSIS, main()
81 .Op Fl a Ar attachment
84 .Op Fl M Ar type | Fl m Ar file | Fl q Ar file | Fl t
86 .Op Fl S Ar var Ns Op Ns = Ns Ar value
91 .Op Fl Fl \~ Ns Ar mta-option ...
100 .Op Fl S Ar var Ns Op Ns = Ns Ar value
103 .Op Fl Fl \~ Ns Ar mta-option ...
111 .Op Fl L Ar spec-list
112 .Op Fl r Ar from-addr
113 .Op Fl S Ar var Ns Op Ns = Ns Ar value
116 .Op Fl Fl \~ Ns Ar mta-option ...
121 .Mx -toc -tree html pdf ps xhtml
124 .\" .Sh DESCRIPTION {{{
127 .Bd -filled -compact -offset indent
128 .Sy Compatibility note:
129 S-nail (\*(UA) will wrap up into \%S-mailx in v15.0 (circa 2018).
130 Backward incompatibility has to be expected \(en
134 -style argument quoting rules, for example.
135 New and old behaviour is flagged \*(IN and \*(OU, and setting
138 .Sx "INTERNAL VARIABLES" ,
139 will choose new behaviour when applicable.
140 \*(OB flags what will vanish, and enabling
144 enables obsoletion warnings.
148 \*(UA is a mail processing system with a command syntax reminiscent of
150 with lines replaced by messages.
151 It is intended to provide the functionality of the POSIX
153 command, but is MIME capable and optionally offers extensions for
154 line editing, S/MIME, SMTP and POP3 among others.
155 It is usable as a mail batch language.
157 .\" .Ss "Options" {{{
160 .Bl -tag -width ".Fl _ Ar _ddr"
163 Explicitly control which of the
165 shall be loaded: if the letter
167 is (case-insensitively) part of the
171 is loaded, likewise the letter
173 controls loading of the user's personal
175 file, whereas the letters
179 explicitly forbid loading of any resource files.
180 This option should be used by scripts: to avoid environmental noise they
183 from any configuration files and create a script-local environment,
184 explicitly setting any of the desired
185 .Sx "INTERNAL VARIABLES"
188 This option overrides
195 command for the given user email
197 after program startup is complete.
198 Being a special incarnation of
200 macros for the purpose of bundling longer-lived settings, activating
201 such an email account also switches to the accounts
207 Attach the given file to the message.
208 The same filename conventions as described in the section
210 apply: shell word expansion is restricted to the tilde
214 not be accessible but contain a
216 character, then anything after the
218 is assumed to specify the input character set and anything before
220 the filename: this is the only option to specify the input character set
221 (and don't perform any character set conversion) for text attachments
222 from the command line, not using the
224 tilde escape command.
228 Make standard input and standard output line-buffered.
232 Send a blind carbon copy to
235 May be used multiple times, but it is also possible to give
236 a comma-separated list of receivers in a single argument, proper quoting
238 .Ql -b """qrec1 , rec2,rec3, Ex <am@ple>""" .
240 .Sx "On sending mail, and non-interactive mode" .
244 Send carbon copies to the given receiver(s).
245 May be used multiple times.
251 variable which enables debug messages and disables message delivery,
252 among others; effectively turns almost any operation into a dry-run.
258 variable and thus discard messages with an empty message part body.
259 This is useful for sending messages from scripts.
263 Just check if mail is present (in the specified or system
265 box): if yes, return an exit status of zero, a non-zero value otherwise.
266 To restrict the set of mails to consider in this evaluation a message
267 specification can be added with the option
272 Save the message to send in a file named after the local part of the
273 first recipient's address (instead of in
278 Read in the contents of the user's
280 (or the specified file) for processing;
281 when \*(UA is quit, it writes undeleted messages back to this file
285 Some special conventions are recognized for the optional
287 argument which are documented for the
292 is not a argument to the flag
294 but is instead taken from the command line after option processing has
298 that starts with a hyphen, prefix it with a (relative) path, as in
299 .Ql ./-hyphenbox.mbox .
303 Display a summary of the
305 of all messages in the specified or system
308 A configurable summary view is available via the
314 Show a short usage summary.
315 Because of widespread use a
317 argument will have the same effect.
323 variable to ignore tty interrupt signals.
326 .It Fl L Ar spec-list
327 Display a summary of all
329 of only those messages in the specified or system
331 box that match the given
335 .Sx "Specifying messages"
342 option has been given in addition no header summary is produced,
343 but \*(UA will instead indicate via its exit status whether
349 note that any verbose output is suppressed in this mode and must instead
350 be enabled explicitly (e.g., by using the option
355 Special send mode that will flag standard input with the MIME
359 and use it as the main message body.
360 \*(ID Using this option will bypass processing of
361 .Va message-inject-head ,
364 .Va message-inject-tail .
370 Special send mode that will MIME classify the specified
372 and use it as the main message body.
373 \*(ID Using this option will bypass processing of
374 .Va message-inject-head ,
377 .Va message-inject-tail .
385 variable and thus inhibit initial display of message headers when
386 reading mail or editing a mail folder.
390 Standard flag that inhibits reading the system wide
395 allows more control over the startup sequence; also see
396 .Sx "Resource files" .
400 Special send mode that will initialize the message body with the
401 contents of the specified
403 which may be standard input
405 only in non-interactive context.
411 Any folder opened will be in read-only mode.
414 .It Fl r Ar from-addr
417 is a valid address then it specifies the envelope sender address to be
420 when a message is send.
423 include a user name, then the address components will be separated and
424 the name part will be passed to the MTA individually via
428 will also be assigned to the
431 .Ql -Sfrom=from-addr ) ,
432 therefore affecting possible SMTP data transfer;
433 note this assignment does not cause value fixation.
435 If instead an empty string is passed as
437 then the content of the variable
439 will be evaluated and used for this purpose whenever the MTA is
441 Note that \*(UA by default, without
443 that is, neither passes
447 flags to the MTA by itself.
450 .It Fl S Ar var Ns Op = Ns value
453 iable and, in case of a value variable, assigns
456 Even though variables (see
457 .Sx "INTERNAL VARIABLES" )
461 may be overwritten from within resource files,
462 the command line setting will be reestablished after all resource files
467 Specify the subject of the to-be-sent message.
471 The message given (on standard input) is expected to contain, separated
472 from the message body with an empty line, a message header with
477 fields giving its recipients, which will be added to those given on the
479 If a message subject is specified via
481 then it'll be used in favour of one given on the command line.
490 Note you can also specify
494 and the envelope address possibly specified with the option
497 The following, which are normally created automatically based
498 upon the message context, can also be specified:
503 .Ql Mail-Followup-To:
504 (special address massage will however still occur for the latter).
505 In fact custom header fields may also be used, the content of which
506 is passed through unchanged.
510 can be embedded, too.
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
573 also no initial header listing will be printed, and processing of
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#
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 the mail-transfer-agent (MTA) and
604 persist for an entire (interactive) session \(en if the setting of
606 allows their recognition;
607 MTA arguments can also be specified in the variable
608 .Va sendmail-arguments ;
609 find MTA interaction described in more detail in the documentation of
611 MTA arguments are ignored when mail is send via SMTP data transfer.
614 .\" .Ss "A starter" {{{
617 \*(UA is a direct descendant of
619 Mail, a successor of the Research
622 .Dq was there from the start
627 Mail reference manual begins with the following words:
629 .Bd -ragged -offset indent
630 Mail provides a simple and friendly environment for sending and
632 It divides incoming mail into its constituent messages and allows the
633 user to deal with them in any order.
634 In addition, it provides a set of
636 -like commands for manipulating messages and sending mail.
637 Mail offers the user simple editing capabilities to ease the composition
638 of outgoing messages, as well as providing the ability to define and
639 send to names which address groups of users.
643 \*(UA is thus the user side of the
645 mail system, whereas the system side (mail-transfer-agent, MTA) was
646 traditionally taken by
652 are often used for this purpose instead.
653 If the \*(OPal SMTP is included in the
655 of \*(UA then the system side is not a mandatory precondition for mail
659 Because \*(UA strives for compliance with POSIX
661 it is likely that some configuration settings have to be adjusted before
662 using it is a smooth experience.
665 file already bends those standard settings a bit towards more user
666 friendliness and safety, e.g., it sets the
670 variables in order to suppress the automatic moving of messages to
672 that would otherwise occur (see
673 .Sx "Message states" )
676 to not remove empty files in order not to mangle file permissions when
677 files eventually get recreated.
680 option so that by default file grouping (via the
682 prefix as documented also for
687 contains some further suggestions.
690 .\" .Ss "On sending mail, and non-interactive mode" {{{
691 .Ss "On sending mail, and non-interactive mode"
693 To send a message to one or more people, using a local
694 mail-transfer-agent (MTA; the executable path can be set via
696 or the \*(OPal builtin SMTP (set and see the variable
698 transport to actually deliver the generated mail message, \*(UA can be
699 invoked with arguments which are the names of people to whom the mail
700 will be sent, and the command line options
704 can be used to add (blind) carbon copy receivers:
706 .Bd -literal -offset indent
707 $ \*(uA -s ubject -a ttach.txt bill@exam.ple
708 # But... try it in an isolated dry-run mode first
709 $ LC_ALL=C \*(uA -:/ -d -vv -Ssendwait \e
710 -b bcc@exam.ple -c cc@exam.ple -s "A subject" -. \e
711 "(Lovely) Bob <bob@exam.ple>" eric@exam.ple
715 If standard input is a terminal rather than the message to be sent,
716 the user is expected to type in the message contents.
717 In this compose mode \*(UA treats lines beginning with the character
719 special \(en these are so-called
721 which can be used to read in files, process shell commands, add and edit
722 attachments and more; e.g., the tilde escape
724 will start the text editor to revise the message in it's current state,
726 allows editing of the most important message headers and
728 gives an overview of available tilde escapes.
732 at the beginning of an empty line leaves compose mode and causes the
733 message to be sent, whereas typing
736 twice will abort the current letter (saving its contents in the file
742 Messages are sent asynchronously unless the variable
744 is set, therefore send errors won't be reported.
750 .Sx "INTERNAL VARIABLES"
751 can be used to alter default behavior; e.g.,
756 will automatically startup a text editor when compose mode is entered,
758 will cause the user to be prompted actively for carbon-copy recipients
761 option will allow leaving compose mode by writing a line consisting
767 hook macros may be set to automatically adjust some settings dependent
768 on receiver, sender or subject contexts.
773 is often necessary (e.g., for
775 transfer), and saving a copy of sent messages in a
777 may be desirable \(en as for most mailbox file targets some special
778 syntax conventions are recognized (see the
780 command for more on that).
783 for the purpose of arranging a complete environment of settings that can
784 be switched to with a single command or command line option may be
787 contains example configurations for sending messages via some of the
788 well-known public mail providers and also gives a compact overview on
789 how to setup a secure SSL/TLS environment).
794 sandbox dry-run tests first will prove correctness.
798 .Sx "On URL syntax and credential lookup"
799 will spread light on the different ways of how to specify user email
800 account credentials, the
802 variable chains, and accessing protocol-specific resources,
805 goes into the details of character encoding and how to use them for
806 representing messages and MIME part contents by specifying them in
808 and reading the section
809 .Sx "The mime.types files"
810 should help to understand how the MIME-type of outgoing attachments are
811 classified, and what can be done for fine-tuning.
814 Message recipients (as specified on the command line or defined in
819 may not only be email addressees but can also be names of mailboxes and
820 even complete shell command pipe specifications.
823 is not set then only network addresses (see
825 for a description of mail addresses) and plain user names (including MTA
826 aliases) may be used, other types will be filtered out, giving a warning
829 .\" When changing any of the following adjust any RECIPIENTADDRSPEC;
830 .\" grep the latter for the complete picture
834 is set then extended recipient addresses will optionally be accepted:
835 Any name which starts with a vertical bar
837 character specifies a command pipe \(en the command string following the
839 is executed and the message is sent to its standard input;
840 Likewise, any name that starts with the character slash
842 or the character sequence dot slash
844 is treated as a file, regardless of the remaining content.
845 Any other name which contains an at sign
847 character is treated as a network address;
848 Any other name which starts with a plus sign
850 character specifies a mailbox name;
851 Any other name which contains a slash
853 character but no exclamation mark
857 character before also specifies a mailbox name;
858 What remains is treated as a network address.
860 .Bd -literal -offset indent
861 $ echo bla | \*(uA -Sexpandaddr -s test ./mbox.mbox
862 $ echo bla | \*(uA -Sexpandaddr -s test '|cat >> ./mbox.mbox'
863 $ echo safe | LC_ALL=C \e
864 \*(uA -:/ -Sv15-compat -Ssendwait -Snosave \e
865 -Sexpandaddr=fail,-all,+addr -s test \e
870 It is possible to create personal distribution lists via the
872 command, so that, for instance, the user can send mail to
874 and have it go to a group of people.
875 These aliases have nothing in common with the system wide aliases that
876 may be used by the MTA (mail-transfer-agent), which are subject to the
880 and are often tracked in a file
886 Personal aliases will be expanded by \*(UA before the message is sent,
887 and are thus a convenient alternative to specifying each addressee by
891 .Dl alias cohorts bill jkf mark kridle@ucbcory ~/mail/cohorts.mbox
894 To avoid environmental noise scripts should
896 \*(UA from any configuration files and create a script-local
897 environment, ideally with the command line options
899 to disable any configuration file in conjunction with repetitions of
901 to specify variables:
903 .Bd -literal -offset indent
905 \*(uA -:/ -Sv15-compat -Ssendwait -Snosave \e
906 -Sexpandaddr=fail,-all,+addr \e
907 -S 'smtp=smtps://mylogin@exam.ple:465' -Ssmtp-auth=login \e
908 -S 'from=scriptreply@exam.ple' \e
909 -s 'subject' -a attachment_file \e
910 -. "Recipient 1 <rec1@exam.ple>" rec2@exam.ple \e
915 In interactive mode, which is introduced in the next section, messages
916 can be sent by calling the
918 command with a list of recipient addresses \(em the semantics are
919 completely identical to non-interactive message sending, except that
920 it is likely necessary to separate recipient lists with commas:
922 .Bd -literal -offset indent
923 $ \*(uA -d -Squiet -Semptystart
924 "/var/spool/mail/user": 0 messages
925 ? mail "Recipient 1 <rec1@exam.ple>", rec2@exam.ple
926 ? # Will do the right thing (tm)
927 ? m rec1@exam.ple rec2@exam.ple
931 .\" .Ss "On reading mail, and interactive mode" {{{
932 .Ss "On reading mail, and interactive mode"
934 When invoked without addressees \*(UA enters interactive mode in which
936 When used like that the user's system
940 for an in-depth description of the different mailbox types that exist)
941 is read in and a one line header of each message therein is displayed.
942 The visual style of this summary of
944 can be adjusted through the variable
946 and the possible sorting criterion via
948 If the initially opened mailbox is empty \*(UA will instead exit
949 immediately (after displaying a message) unless the variable
958 will give a listing of all available commands and
960 will give a summary of some common ones.
961 If the \*(OPal documentation strings are available one can type
963 and see the actual expansion of
965 and what it's purpose is, i.e., commands can be abbreviated
966 (note that POSIX defines some abbreviations, so that the alphabetical
967 order of commands doesn't necessarily relate to the abbreviations; it is
968 possible to define overwrites with the
973 Messages are given numbers (starting at 1) which uniquely identify
974 messages; the current message \(en the
976 \(en will either be the first new message, or the first unread message,
977 or the first message of the mailbox; the option
979 will instead cause usage of the last message for this purpose.
984 ful of header summaries containing the
988 will display only the summaries of the given messages, defaulting to the
992 Messages can be displayed on the user's terminal with the
996 By default the current message
998 is displayed, but like with many other commands it is possible to give
999 a fancy message specification (see
1000 .Sx "Specifying messages" ) ,
1003 will display all unread messages,
1008 will type the messages 1 and 5,
1010 will type the messages 1 through 5, and
1014 will display the last and the next message, respectively.
1017 (a more substantial alias of the standard command
1019 will display a header summary of the given message specification list
1020 instead of their content, e.g., the following will search for subjects:
1023 .Dl from """@Some subject to search for"""
1026 In the default setup all header fields of a message will be displayed,
1027 but this can be changed: either by blacklisting a list of fields via
1029 or by whitelisting only a given list with the
1032 .Ql Ic \:retain Ns \0date from to cc subject .
1033 In order to display all header fields of a message regardless of
1034 currently active ignore or retain lists, use the command
1038 controls whether and when \*(UA will use the configured
1040 for display instead of directly writing to the user terminal
1041 (generally speaking).
1042 Note that historically the global
1044 not only adjusts the list of displayed headers, but also sets
1048 Dependent upon the configuration a line editor (see the section
1049 .Sx "On terminal control and line editor" )
1050 aims at making user experience with the many
1053 When reading the system
1059 specified a mailbox explicitly prefixed with the special
1061 modifier (propagating the mailbox to a primary one) then messages which
1062 have been read will be moved to a secondary mailbox, the user's
1064 file, automatically when the mailbox is left, either by changing the
1065 active mailbox or by quitting \*(UA (also see
1066 .Sx "Message states" )
1067 \(en this automatic moving from a system or primary to the secondary
1068 mailbox is not performed when the variable
1073 After examining a message the user can also
1077 to the sender and all recipients or
1079 exclusively to the sender(s).
1080 Messages can also be
1082 ed (shorter alias is
1084 Note that when replying to or forwarding a message recipient addresses
1085 will be stripped from comments and names unless the option
1088 Deletion causes \*(UA to forget about the message;
1089 This is not irreversible, though, one can
1091 the message by giving its number,
1092 or the \*(UA session can be ended by giving the
1097 To end a mail processing session one may either issue
1099 to cause a full program exit, which possibly includes
1100 automatic moving of read messages to
1102 as well as updating the \*(OPal line editor
1106 instead in order to prevent any of these actions.
1109 .\" .Ss "HTML mail and MIME attachments" {{{
1110 .Ss "HTML mail and MIME attachments"
1112 Messages which are HTML-only get more and more common and of course many
1113 messages come bundled with a bouquet of MIME attachments.
1114 Whereas \*(UA \*(OPally supports a simple HTML-to-text converter to deal
1115 with HTML messages (see
1116 .Sx "The mime.types files" ) ,
1117 it normally can't deal with any of these itself, but instead programs
1118 need to become registered to deal with specific MIME types or file
1120 These programs may either prepare plain text versions of their input
1121 in order to enable \*(UA to display the content on the terminal,
1122 or display the content themselves, for example in a graphical window.
1125 To install an external handler program for a specific MIME type set an
1127 .Va pipe-TYPE/SUBTYPE
1128 variable; to instead define a handler for a specific file extension set
1131 variable \(en these handlers take precedence.
1132 \*(OPally \*(UA supports mail user agent configuration as defined in
1133 RFC 1524; this mechanism, documented in the section
1134 .Sx "The Mailcap files" ,
1135 will be queried for display or quote handlers if none of the former two
1136 .\" TODO v15-compat "will be" -> "is"
1137 did; it will be the sole source for handlers of other purpose.
1138 A last source for handlers may be the MIME type definition itself, if
1139 the \*(UA specific type-marker extension was used when defining the type
1142 (Many of the builtin MIME types do so by default.)
1146 .Va mime-counter-evidence
1147 can be set to improve dealing with faulty MIME part declarations as are
1148 often seen in real-life messages.
1149 E.g., to display a HTML message inline (that is, converted to a more
1150 fancy plain text representation than the builtin converter is capable to
1151 produce) with either of the text-mode browsers
1155 teach \*(UA about MathML documents and make it display them as plain
1156 text, and to open PDF attachments in an external PDF viewer,
1157 asynchronously and with some other magic attached:
1159 .Bd -literal -offset indent
1160 if $features !@ HTML-FILTER
1161 #set pipe-text/html='elinks -force-html -dump 1'
1162 set pipe-text/html='lynx -stdin -dump -force_html'
1163 # Display HTML as plain text instead
1164 #set pipe-text/html=@
1166 mimetype '@ application/mathml+xml mathml'
1167 wysh set pipe-application/pdf='@&=@ \e
1168 trap "rm -f \e"${NAIL_FILENAME_TEMPORARY}\e"" EXIT;\e
1169 trap "trap \e"\e" INT QUIT TERM; exit 1" INT QUIT TERM;\e
1170 mupdf "${NAIL_FILENAME_TEMPORARY}"'
1174 Note: special care must be taken when using such commands as mail
1175 viruses may be distributed by this method: if messages of type
1176 .Ql application/x-sh
1177 or files with the extension
1179 were blindly filtered through the shell, for example, a message sender
1180 could easily execute arbitrary code on the system \*(UA is running on.
1181 For more on MIME, also in respect to sending of messages, see the
1183 .Sx "The mime.types files" ,
1184 .Sx "The Mailcap files"
1189 .\" .Ss "Mailing lists" {{{
1192 \*(UA offers some support to ease handling of mailing lists.
1195 promotes all given arguments to known mailing lists, and
1197 sets their subscription attribute, creating them first as necessary.
1202 automatically, but only resets the subscription attribute.)
1203 Using the commands without arguments will show (a subset of) all
1204 currently defined mailing lists.
1209 can be used to mark out messages with configured list addresses
1210 in the header display.
1213 \*(OPally mailing lists may also be specified as (extended) regular
1214 expressions, which allows matching of many addresses with a single
1216 However, all fully qualified list addresses are matched via a fast
1217 dictionary, whereas expressions are placed in (a) list(s) which is
1218 (are) matched sequentially.
1220 .Bd -literal -offset indent
1221 set followup-to followup-to-honour=ask-yes reply-to-honour=ask-yes
1222 wysh mlist a1@b1.c1 a2@b2.c2 '.*@lists\e.c3$'
1223 mlsubscribe a4@b4.c4 exact@lists.c3
1228 .Va followup-to-honour
1230 .Ql Mail-\:Followup-\:To:
1231 header is honoured when the message is being replied to (via
1237 controls whether this header is created when sending mails; it will be
1238 created automatically for a couple of reasons, too, like when the
1240 .Dq mailing list specific
1245 is used to respond to a message with its
1246 .Ql Mail-Followup-To:
1250 A difference in between the handling of known and subscribed lists is
1251 that the address of the sender is usually not part of a generated
1252 .Ql Mail-Followup-To:
1253 when addressing the latter, whereas it is for the former kind of lists.
1254 Usually because there are exceptions: say, if multiple lists are
1255 addressed and not all of them are subscribed lists.
1257 For convenience \*(UA will, temporarily, automatically add a list
1258 address that is presented in the
1260 header of a message that is being responded to to the list of known
1262 Shall that header have existed \*(UA will instead, dependent on the
1264 .Va reply-to-honour ,
1267 for this purpose in order to accept a list administrators' wish that
1268 is supposed to have been manifested like that (but only if it provides
1269 a single address which resides on the same domain as what is stated in
1273 .\" .Ss "Resource files" {{{
1274 .Ss "Resource files"
1276 Upon startup \*(UA reads in several resource files:
1278 .Bl -tag -width ".It Pa _AIL_EXTRA_R_"
1281 System wide initialization file.
1282 Reading of this file can be suppressed, either by using the
1286 command line options, or by setting the
1289 .Ev NAIL_NO_SYSTEM_RC .
1293 File giving initial commands.
1294 A different file can be chosen by setting the
1298 Reading of this file can be suppressed with the
1300 command line option.
1302 .It Va NAIL_EXTRA_RC
1303 Can be used to define an optional startup file to be read after all
1304 other resource files.
1305 It can be used to specify settings that are not understood by other
1307 implementations, for example.
1308 This variable is only honoured when defined in a resource file, e.g.,
1310 .Sx "INTERNAL VARIABLES" .
1314 The content of these files is interpreted as follows:
1317 .Bl -bullet -compact
1319 A lines' leading whitespace is removed.
1321 Empty lines are ignored.
1323 Any other line is interpreted as a command.
1324 It may be spread over multiple input lines if the newline character is
1326 by placing a backslash character
1328 as the last character of the line; whereas any leading whitespace of
1329 follow lines is ignored, trailing whitespace before a escaped newline
1330 remains in the input.
1332 If the line (content) starts with the number sign
1334 then it is a comment-command \(en a real command! \(en and also ignored.
1335 This command is the only form of comment that is understood.
1339 Unless \*(UA is about to enter interactive mode syntax errors that occur
1340 while loading these files are treated as errors and cause program exit.
1341 More files with syntactically equal content can be
1343 The following, saved in a file, would be an examplary content:
1345 .Bd -literal -offset indent
1346 # This line is a comment command. And y\e
1347 es, it is really continued here.
1354 .\" .Ss "Character sets" {{{
1355 .Ss "Character sets"
1357 \*(OP \*(UA detects the character set of the terminal by using
1358 mechanisms that are controlled by the
1363 should give an overview); the \*(UA internal variable
1365 will be set to the detected terminal character set accordingly
1366 and will thus show up in the output of the commands
1372 However, a user supplied
1374 value is not overwritten by this detection mechanism: this
1376 must be used if the detection doesn't work properly,
1377 and it may be used to adjust the name of the locale character set.
1378 E.g., on BSD systems one may use a locale with the character set
1379 ISO8859-1, which is not a valid name for this character set; to be on
1380 the safe side, one may set
1382 to the correct name, which is ISO-8859-1.
1385 Note that changing the value doesn't mean much beside that,
1386 since several aspects of the real character set are implied by the
1387 locale environment of the system,
1388 and that stays unaffected by the content of an overwritten
1391 (This is mostly an issue when interactively using \*(UA, though.
1392 It is actually possible to send mail in a completely
1394 locale environment, an option that \*(UA's test-suite uses excessively.)
1397 If no character set conversion capabilities have been compiled into
1400 doesn't include the term
1404 will be the only supported character set,
1405 it is simply assumed that it can be used to exchange 8-bit messages,
1406 and the rest of this section does not apply;
1407 it may however still be necessary to explicitly set it if automatic
1408 detection fails, since in that case it defaults to the mentioned
1409 .\" (Keep in SYNC: ./nail.1:"Character sets", ./nail.h:CHARSET_*!)
1413 When reading messages, their text is converted into
1415 as necessary in order to display them on the users terminal.
1416 Unprintable characters and invalid byte sequences are detected
1417 and replaced by proper substitution characters (unless the variable
1419 was set once \*(UA was started).
1421 .Va charset-unknown-8bit
1422 to deal with another hairy aspect of message interpretation.
1425 When sending messages all their parts and attachments are classified.
1426 Whereas no character set conversion is performed on those parts which
1427 appear to be binary data,
1428 the character set being used must be declared within the MIME header of
1429 an outgoing text part if it contains characters that do not conform to
1430 the set of characters that are allowed by the email standards.
1431 Permissible values for character sets can be declared using the
1435 which defines a catch-all last-resort fallback character set that is
1436 implicitly appended to the list of character-sets in
1440 When replying to a message and the variable
1441 .Va reply-in-same-charset
1442 is set then the character set of the message being replied to is tried
1444 And it is also possible to make \*(UA work even more closely related to
1445 the current locale setting automatically by using the variable
1446 .Va sendcharsets-else-ttycharset ,
1447 please see there for more information.
1450 All the specified character sets are tried in order unless the
1451 conversion of the part or attachment succeeds.
1452 If none of the tried (8-bit) character sets is capable to represent the
1453 content of the part or attachment,
1454 then the message will not be sent and its text will optionally be
1458 In general, if the message
1459 .Dq Cannot convert from a to b
1460 appears, either some characters are not appropriate for the currently
1461 selected (terminal) character set,
1462 or the needed conversion is not supported by the system.
1463 In the first case, it is necessary to set an appropriate
1465 locale and/or the variable
1469 The best results are usually achieved when \*(UA is run in a UTF-8
1470 locale on a UTF-8 capable terminal, in which case the full Unicode
1471 spectrum of characters is available.
1472 In this setup characters from various countries can be displayed,
1473 while it is still possible to use more simple character sets for sending
1474 to retain maximum compatibility with older mail clients.
1477 On the other hand the POSIX standard defines a locale-independent 7-bit
1478 .Dq portable character set
1479 that should be used when overall portability is an issue, the even more
1480 restricted subset named
1481 .Dq portable filename character set
1482 consisting of A-Z, a-z, 0-9, period
1491 .\" .Ss "Message states" {{{
1492 .Ss "Message states"
1494 \*(UA differentiates in between several different message states;
1495 the current state will be reflected in header summary displays if
1497 is configured to do so (via the internal variable
1499 and messages can also be selected and be acted upon depending on their
1501 .Sx "Specifying messages" ) .
1502 When operating on the system
1504 box or in primary mailboxes opened with the special prefix
1508 special actions, like the automatic moving of messages to the secondary
1510 mailbox may be applied when the mailbox is left (also implicitly via
1511 a successful exit of \*(UA, but not if the special command
1513 is used) \(en however, because this may be irritating to users which
1516 mail-user-agents, the default global
1522 variables in order to suppress this behaviour.
1524 .Bl -tag -width ".It Ql _reserved"
1526 Message has neither been viewed nor moved to any other state.
1527 Such messages are retained even in the primary system mailbox.
1530 Message has neither been viewed nor moved to any other state, but the
1531 message was present already when the mailbox has been opened last:
1532 Such messages are retained even in the primary system mailbox.
1535 The message has been processed by one of the following commands:
1555 commands may also cause the next message to be marked as read, depending
1561 command is used, messages that are in the primary system mailbox or in
1562 mailboxes which were opened with the special
1566 state when the mailbox is left will be saved in
1573 The message has been processed by one of the following commands:
1579 can be used to access such messages.
1582 The message has been processed by a
1584 command and it will be retained in its current location.
1587 The message has been processed by one of the following commands:
1593 command is used, messages that are in the primary system mailbox or in
1594 mailboxes which were opened with the special
1598 state when the mailbox is left will be deleted; they will be saved in
1606 .\" .Ss "Specifying messages" {{{
1607 .Ss "Specifying messages"
1614 can be given a list of message numbers as arguments to apply to a number
1615 of messages at once.
1618 deletes messages 1 and 2,
1621 will delete the messages 1 through 5.
1622 In sorted or threaded mode (see the
1626 will delete the messages that are located between (and including)
1627 messages 1 through 5 in the sorted/threaded order, as shown in the
1630 Multiple colon modifiers can be joined into one, e.g.,
1632 The following special message names exist:
1634 .Bl -tag -width ".It Ar _n_u"
1640 All old messages (any not in state
1665 All answered messages
1670 All messages marked as draft.
1672 \*(OP All messages classified as spam.
1674 \*(OP All messages with unsure spam classification.
1676 The current message, the so-called
1679 The message that was previously the current message.
1681 The parent message of the current message,
1682 that is the message with the Message-ID given in the
1684 field or the last entry of the
1686 field of the current message.
1688 The next previous undeleted message,
1689 or the next previous deleted message for the
1692 In sorted/threaded mode,
1693 the next previous such message in the sorted/threaded order.
1695 The next undeleted message,
1696 or the next deleted message for the
1699 In sorted/threaded mode,
1700 the next such message in the sorted/threaded order.
1702 The first undeleted message,
1703 or the first deleted message for the
1706 In sorted/threaded mode,
1707 the first such message in the sorted/threaded order.
1710 In sorted/threaded mode,
1711 the last message in the sorted/threaded order.
1715 selects the message addressed with
1719 is any other message specification,
1720 and all messages from the thread that begins at it.
1721 Otherwise it is identical to
1726 the thread beginning with the current message is selected.
1731 All messages that were included in the message list for the previous
1734 .It Ar / Ns Ar string
1735 All messages that contain
1737 in the subject field (case ignored).
1744 the string from the previous specification of that type is used again.
1746 .It Xo Op Ar @ Ns Ar name-list Ns
1749 All messages that contain the given case-insensitive search
1751 ession; if the \*(OPal regular expression (see
1753 support is available
1755 will be interpreted as (an extended) one if any of the
1757 (extended) regular expression characters is seen.
1759 .Ar @ Ns Ar name-list
1760 part is missing, the search is restricted to the subject field body,
1763 specifies a comma-separated list of header fields to search, as in
1765 .Dl '@to,from,cc@Someone i ought to know'
1767 In order to search for a string that includes a
1769 (commercial at) character the
1771 is effectively non-optional, but may be given as the empty string.
1772 Some special header fields may be abbreviated:
1786 respectively and case-insensitively.
1791 can be used to search in (all of) the header(s) of the message, and the
1800 can be used to perform full text searches \(en whereas the former
1801 searches only the body, the latter also searches the message header.
1803 This message specification performs full text comparison, but even with
1804 regular expression support it is almost impossible to write a search
1805 expression that savely matches only a specific address domain.
1806 To request that the content of the header is treated as a list of
1807 addresses, and to strip those down to the plain email address which the
1808 search expression is to be matched against, prefix the header name
1809 (abbreviation) with a tilde
1812 .Dl @~f@@a\e.safe\e.domain\e.match$
1816 .Dq any substring matches
1819 header, which will match addresses (too) even if
1821 is set (and POSIX says
1822 .Dq any address as shown in a header summary shall be matchable in this form ) ;
1825 variable is set, only the local part of the address is evaluated
1826 for the comparison, not ignoring case, and the setting of
1828 is completely ignored.
1829 For finer control and match boundaries use the
1831 search expression; the \*(OPal IMAP-style
1833 expression can also be used if substring matches are desired.
1837 \*(OP IMAP-style SEARCH expressions may also be used.
1838 This addressing mode is available with all types of folders;
1839 \*(UA will perform the search locally as necessary.
1840 Strings must be enclosed by double quotes
1842 in their entirety if they contain white space or parentheses;
1843 within the quotes, only backslash
1845 is recognized as an escape character.
1846 All string searches are case-insensitive.
1847 When the description indicates that the
1849 representation of an address field is used,
1850 this means that the search string is checked against both a list
1853 .Bd -literal -offset indent
1854 (\*qname\*q \*qsource\*q \*qlocal-part\*q \*qdomain-part\*q)
1859 and the addresses without real names from the respective header field.
1860 These search expressions can be nested using parentheses, see below for
1864 .Bl -tag -compact -width ".It Ar _n_u"
1865 .It Ar ( criterion )
1866 All messages that satisfy the given
1868 .It Ar ( criterion1 criterion2 ... criterionN )
1869 All messages that satisfy all of the given criteria.
1871 .It Ar ( or criterion1 criterion2 )
1872 All messages that satisfy either
1877 To connect more than two criteria using
1879 specifications have to be nested using additional parentheses,
1881 .Ql (or a (or b c)) ,
1885 .Ql ((a or b) and c) .
1888 operation of independent criteria on the lowest nesting level,
1889 it is possible to achieve similar effects by using three separate
1893 .It Ar ( not criterion )
1894 All messages that do not satisfy
1896 .It Ar ( bcc \*q Ns Ar string Ns Ar \*q )
1897 All messages that contain
1899 in the envelope representation of the
1902 .It Ar ( cc \*q Ns Ar string Ns Ar \*q )
1903 All messages that contain
1905 in the envelope representation of the
1908 .It Ar ( from \*q Ns Ar string Ns Ar \*q )
1909 All messages that contain
1911 in the envelope representation of the
1914 .It Ar ( subject \*q Ns Ar string Ns Ar \*q )
1915 All messages that contain
1920 .It Ar ( to \*q Ns Ar string Ns Ar \*q )
1921 All messages that contain
1923 in the envelope representation of the
1926 .It Ar ( header name \*q Ns Ar string Ns Ar \*q )
1927 All messages that contain
1932 .It Ar ( body \*q Ns Ar string Ns Ar \*q )
1933 All messages that contain
1936 .It Ar ( text \*q Ns Ar string Ns Ar \*q )
1937 All messages that contain
1939 in their header or body.
1940 .It Ar ( larger size )
1941 All messages that are larger than
1944 .It Ar ( smaller size )
1945 All messages that are smaller than
1949 .It Ar ( before date )
1950 All messages that were received before
1952 which must be in the form
1956 denotes the day of the month as one or two digits,
1958 is the name of the month \(en one of
1959 .Ql Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ,
1962 is the year as four digits, e.g.,
1966 All messages that were received on the specified date.
1967 .It Ar ( since date )
1968 All messages that were received since the specified date.
1969 .It Ar ( sentbefore date )
1970 All messages that were sent on the specified date.
1971 .It Ar ( senton date )
1972 All messages that were sent on the specified date.
1973 .It Ar ( sentsince date )
1974 All messages that were sent since the specified date.
1976 The same criterion as for the previous search.
1977 This specification cannot be used as part of another criterion.
1978 If the previous command line contained more than one independent
1979 criterion then the last of those criteria is used.
1983 .\" .Ss "On URL syntax and credential lookup" {{{
1984 .Ss "On URL syntax and credential lookup"
1986 \*(IN For accessing protocol-specific resources usage of Uniform
1987 Resource Locators (URL, RFC 1738) has become omnipresent.
1988 \*(UA expects and understands URLs in the following form;
1991 denote optional parts, optional either because there also exist other
1992 ways to define the information in question or because support of the
1993 part is protocol-specific (e.g.,
1995 is used by the IMAP protocol but not by POP3);
2000 are specified they must be given in URL percent encoded form (RFC 3986;
2008 .Dl PROTOCOL://[USER[:PASSWORD]@]server[:port][/path]
2011 Note that these \*(UA URLs most often don't conform to any real
2012 standard, but instead represent a normalized variant of RFC 1738 \(en
2013 they are not used in data exchange but only meant as a compact,
2014 easy-to-use way of defining and representing information in
2015 a well-known notation.
2018 Many internal variables of \*(UA exist in multiple versions, called
2019 variable chains for the rest of this document: the plain
2024 .Ql variable-USER@HOST .
2031 had been specified in the respective URL, otherwise it refers to the plain
2037 that had been found when doing the user chain lookup as is described
2040 will never be in URL percent encoded form, whether it came from an URL
2041 or not; i.e., values of
2042 .Sx "INTERNAL VARIABLES"
2043 must not be URL percent encoded.
2046 For example, whether an hypothetical URL
2047 .Ql smtp://hey%3Ayou@our.house
2048 had been given that includes a user, or whether the URL was
2049 .Ql smtp://our.house
2050 and the user had been found differently, to lookup the variable chain
2051 .Va smtp-use-starttls
2052 \*(UA first looks for whether
2053 .Ql smtp-\:use-\:starttls-\:hey:you@our.house
2054 is defined, then whether
2055 .Ql smtp-\:use-\:starttls-\:our.house
2056 exists before finally ending up looking at the plain variable itself.
2059 \*(UA obeys the following logic scheme when dealing with the
2060 necessary credential information of an account:
2066 has been given in the URL the variables
2070 are looked up; if no such variable(s) can be found then \*(UA will,
2071 when enforced by the \*(OPal variables
2072 .Va netrc-lookup-HOST
2079 specific entry which provides a
2081 name: this lookup will only succeed if unambiguous (one possible matching
2085 If there is still no
2087 then \*(UA will fall back to the user who is supposed to run \*(UA,
2088 the identity of which has been fixated during \*(UA startup and is
2089 known to be a valid user on the current host.
2092 Authentication: unless otherwise noted this will lookup the
2093 .Va PROTOCOL-auth-USER@HOST , PROTOCOL-auth-HOST , PROTOCOL-auth
2094 variable chain, falling back to a protocol-specific default should this
2100 has been given in the URL, then if the
2102 has been found through the \*(OPal
2104 then that may have already provided the password, too.
2105 Otherwise the variable chain
2106 .Va password-USER@HOST , password-HOST , password
2107 is looked up and used if existent.
2109 \*(OP Then if any of the variables of the chain
2110 .Va agent-shell-lookup-USER@HOST , agent-shell-lookup-HOST , \
2112 is set the shell command specified therein is run and the output (less
2113 newline characters) will be used as the password.
2114 It is perfectly valid for such an agent to simply not return any data,
2115 in which case the password lookup is continued somewhere else;
2116 Any command failure is treated as a hard error, however.
2118 Afterwards the complete \*(OPal variable chain
2119 .Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup
2123 cache is searched for a password only (multiple user accounts for
2124 a single machine may exist as well as a fallback entry without user
2125 but with a password).
2127 If at that point there is still no password available, but the
2128 (protocols') chosen authentication type requires a password, then in
2129 interactive mode the user will be prompted on the terminal.
2134 S/MIME verification works relative to the values found in the
2138 header field(s), which means that the values of
2139 .Va smime-sign , smime-sign-cert , smime-sign-include-certs
2141 .Va smime-sign-message-digest
2142 will not be looked up using the
2146 chains from above but instead use the corresponding values from the
2147 message that is being worked on.
2148 In unusual cases multiple and different
2152 combinations may therefore be involved \(en on the other hand those
2153 unusual cases become possible.
2154 The usual case is as short as:
2157 .Dl set smtp=smtp://USER:PASS@HOST smtp-use-starttls \e
2158 .Dl \ \ \ \ smime-sign smime-sign-cert=+smime.pair
2163 contains complete example configurations.
2166 .\" .Ss "On terminal control and line editor" {{{
2167 .Ss "On terminal control and line editor"
2169 \*(OP \*(UA can be configured to support a line editor,
2170 history lists that can be saved in between sessions,
2171 and terminal control to improve interactive usage experience.
2172 For the former one may either link against an external library
2173 .Pf ( Xr readline 3 ;
2174 behaviour of \*(UA may differ slightly),
2175 or enable the builtin Mailx-Line-Editor (MLE), which should work in all
2176 environments which comply to the ISO C standard
2178 and which will support wide glyphs if possible (the necessary
2179 functionality had been removed from ISO C, but was included in
2181 Prevent usage of a line editor in interactive mode by setting the
2183 .Va line-editor-disable .
2188 feature is available then input from line editor prompts will be saved
2189 in a history list that can be searched in and be expanded from.
2190 Such saving can be prevented by prefixing input with any amount of
2192 Aspects of history, like allowed content, maximum size etc., can be
2193 configured with the variables
2196 .Va history-gabby-persist
2201 \*(OP Terminal control will be realized through one of the standard
2203 libraries, either the
2205 or, alternatively, the
2207 both of which will be initialized to work with the environment variable
2209 Terminal control will enhance or enable interactive usage aspects, e.g.,
2210 .Sx "Coloured display" ,
2211 and extend behaviour of the MLE, which may learn the key-sequences of
2212 keys like the cursor and function keys, and which will automatically
2215 alternative screen shall the terminal support it.
2216 The internal variable
2218 can be used to overwrite settings or to learn (correct(ed)) keycodes.
2219 Actual interaction with the chosen library can be disabled completely by
2220 setting the internal variable
2221 .Va termcap-disable ,
2222 which may be necessary for proper operation on the actual terminal;
2224 will be queried regardless, even if the \*(OPal support for the
2225 libraries has not been enabled at configuration time.
2228 \*(OP The builtin \*(UA line editor MLE supports the following
2229 operations; the notation
2231 stands for the combination of the
2233 key plus the mentioned character, e.g.,
2236 .Dq hold down control key and press the A key .
2237 Especially without termcap support setting respective entries in
2239 will help shall the MLE misbehave.
2240 The MLE also supports several
2245 .Bl -tag -compact -width "Ql _M"
2247 Go to the start of the line.
2249 Move the cursor backward one character.
2251 Forward delete the character under the cursor;
2252 quits \*(UA if used on the empty line unless the
2256 Go to the end of the line.
2258 Move the cursor forward one character.
2261 Cancel current operation, full reset.
2262 If there is an active history search or tabulator expansion then this
2263 command will first reset that, reverting to the former line content;
2264 thus a second reset is needed for a full reset in this case.
2265 In all cases \*(UA will reset a possibly used multibyte character input
2271 backward delete one character.
2275 .Dq horizontal tabulator :
2276 try to expand the word before the cursor, also supporting \*(UA
2283 complete this line of input.
2285 Delete all characters from the cursor to the end of the line.
2289 \*(OP Go to the next history entry.
2294 \*(OP Go to the previous history entry.
2296 \*(OP Complete the current line from (the remaining older) history entries.
2303 Prompts for a Unicode character to be inserted.
2305 Delete the characters from the one preceding the cursor to the preceding
2308 Move the cursor forward one word boundary.
2310 Move the cursor backward one word boundary.
2314 If the keycodes are known then the left and right cursor keys will map to
2318 respectively, the up and down cursor keys will map to
2322 and the Home/End/PgUp/PgDown keys will call the
2324 command with the respective arguments
2330 (i.e., perform scrolling through the header summary list).
2331 Also the up and down cursor keys should invoke
2333 for up- and downwards movement if they are used while the
2338 .\" .Ss "Coloured display" {{{
2339 .Ss "Coloured display"
2341 \*(OP \*(UA can be configured to support a coloured display and font
2342 attributes by emitting ANSI / ISO 6429 SGR (select graphic rendition)
2344 Usage of colours and font attributes solely depends upon the
2345 capability of the detected terminal type that is defined by the
2346 environment variable
2348 and which can be fine-tuned by the user via the internal variable
2352 On top of what \*(UA knows about the terminal the boolean variable
2354 defines whether the actually applicable colour and font attribute
2355 sequences should also be generated when output is going to be paged
2356 through the external program defined by the environment variable
2361 This is not enabled by default because different pager programs need
2362 different command line switches or other configuration in order to
2363 support those sequences.
2364 \*(UA however knows about some widely used pagers and in a clean
2365 environment it is often enough to simply set
2367 please refer to that variable for more on this topic.
2372 is set then any active usage of colour and font attribute sequences
2373 is suppressed, but without affecting possibly established
2378 To define and control colours and font attributes a single multiplexer
2379 command family exists:
2381 shows or defines colour mappings for the given colour type (e.g.,
2384 can be used to remove mappings of a given colour type.
2385 Since colours are only available in interactive mode, it may make
2386 sense to conditionalize the colour setup by encapsulating it with
2389 .Bd -literal -offset indent
2390 if terminal && $features =@ +colour
2391 colour iso view-msginfo ft=bold,fg=green
2392 colour iso view-header ft=bold,fg=red "from,subject"
2393 colour iso view-header fg=red
2395 uncolour iso view-header from,subject
2396 colour iso view-header ft=bold,fg=magenta,bg=cyan
2397 colour 256 view-header ft=bold,fg=208,bg=230 subject,from
2398 colour mono view-header ft=bold
2399 colour mono view-header ft=bold,ft=reverse subject,from
2403 .\" }}} (DESCRIPTION)
2406 .\" .Sh COMMANDS {{{
2409 Each command is typed on a line by itself,
2410 and may take arguments following the command word.
2411 Command names may be abbreviated, in which case the first command that
2412 matches the given prefix will be used.
2415 can be used to show the list of all commands, either alphabetically
2416 sorted or in prefix search order (these don't match, also because the
2417 POSIX standard prescribes a set of abbreviations); a more verbose
2418 listing will be produced if either of
2423 \*(OPally the command
2427 when given an argument, will show a documentation string for the
2428 command matching the expanded argument, as in
2430 which should be a shorthand of
2434 For commands which take message lists as arguments, the next message
2435 forward that satisfies the command's requirements will be used shall no
2436 explicit message list have been specified.
2437 If there are no messages forward of the current message,
2438 the search proceeds backwards,
2439 and if there are no good messages at all,
2440 \*(UA shows an error message and aborts the command.
2441 \*(ID Non-message-list arguments can be quoted using the following methods:
2444 .Bl -bullet -compact -offset indent
2446 An argument can be enclosed between paired double-quotes
2451 any white space, shell word expansion, or backslash characters (except
2452 as described next) within the quotes are treated literally as part of
2454 A double-quote will be treated literally within single-quotes and vice
2456 Inside such a quoted string the actually used quote character can be
2457 used nonetheless by escaping it with a backslash
2463 An argument that is not enclosed in quotes, as above, can usually still
2464 contain space characters if those spaces are backslash-escaped, as in
2468 A backslash outside of the enclosing quotes is discarded
2469 and the following character is treated literally as part of the argument.
2474 Some commands which don't take message-list arguments can also be
2475 prefixed with the special keyword
2477 to choose \*(INible behaviour, and some new commands support only the
2478 new quoting style (without that keyword) and are flagged \*(NQ.
2479 In the future \*(UA will (mostly) use
2481 compatible argument parsing:
2482 Non-message-list arguments can be quoted using the following shell-style
2483 mechanisms: the escape character, single-quotes, double-quotes and
2484 dollar-single-quotes; any unquoted number sign
2486 starts a comment that ends argument processing.
2487 The overall granularity of error reporting and diagnostics, also
2488 regarding function arguments and their content, will improve.
2492 .Bl -bullet -compact -offset indent
2494 The literal value of any character can be preserved by preceding it
2495 with the escape character backslash
2499 will cause variable expansion of the given name: \*(UA
2500 .Sx "INTERNAL VARIABLES"
2503 (shell) variables can be accessed through this mechanism, brace
2504 enclosing the name is supported.
2507 Arguments which are enclosed in
2508 .Ql 'single-\:quotes'
2509 retain their literal value.
2510 A single-quote cannot occur within single-quotes.
2513 The literal value of all characters enclosed in
2514 .Ql \(dqdouble-\:quotes\(dq
2515 is retained, with the exception of dollar
2517 which will cause variable expansion, as above, backquote (grave accent)
2519 (which not yet means anything special), backslash
2521 which will escape any of the characters dollar
2523 (to prevent variable expansion), backquote (grave accent)
2527 (to prevent ending the quote) and backslash
2529 (to prevent escaping, i.e., to embed a backslash character as-is), but
2530 has no special meaning otherwise.
2533 Arguments enclosed in
2534 .Ql $'dollar-\:single-\:quotes'
2535 extend normal single quotes in that backslash escape sequences are
2536 expanded as follows:
2538 .Bl -tag -compact -width "Ql \eNNN"
2544 an escape character.
2546 an escape character.
2558 backslash character.
2562 double quote (escaping is optional).
2564 eight-bit byte with the octal value
2566 (one to three octal digits), optionally with an additional
2569 A 0 byte will suppress further output for the quoted argument.
2571 eight-bit byte with the hexadecimal value
2573 (one or two hexadecimal characters).
2574 A 0 byte will suppress further output for the quoted argument.
2576 the Unicode / ISO-10646 character with the hexadecimal codepoint value
2578 (one to eight hexadecimal digits) \(em note that Unicode defines the
2579 maximum code to be ever supported as
2584 This escape is only supported in locales which support Unicode (see
2585 .Sx "Character sets" ) ,
2586 in other cases the sequence will remain unexpanded unless the given code
2587 point is ASCII compatible.
2588 The character NUL will suppress further output for the quoted argument.
2592 except it takes only one to four hexadecimal digits.
2597 This is a mechanism that allows usage of the non-printable (ASCII and
2598 compatible) control codes 0 to 31: to be able to create a printable
2599 representation the numeric value 64 is added to the control code of
2600 desire, and the resulting ASCII character set code point is then
2601 printed, e.g., BEL is
2602 .Ql 7 + 64 = 71 = G .
2603 Often circumflex notation is used for the visualization purpose, e.g,
2605 but the reverse solid notation has been standardized:
2607 The control code NUL
2609 ends argument processing without producing further output.
2611 Non-standard extension: expand the given variable name, as above.
2612 Brace enclosing the name is supported.
2614 Not yet supported, just to raise awareness: Non-standard extension.
2620 .Sy Compatibility notes:
2621 \*(ID Note these are new mechanisms which are not supported by all
2623 Round-tripping (feeding in things shown in list modes again) are not yet
2624 stable or possible at all.
2625 On new-style command lines it is wise to quote semicolon
2629 characters in order to ensure upward compatibility: the author would
2630 like to see things like
2631 .Ql ? echo $'trouble\tahead' | cat >> in_the_shell.txt
2633 .Ql ? top 2 5 10; type 3 22
2635 Before \*(UA will switch entirely to shell-style argument parsing there
2636 will be a transition phase where using
2638 will emit obsoletion warnings.
2639 E.g., the following are equivalent:
2641 .Bd -literal -offset indent
2642 mlist @any\e\e.where\e\e.example\e\e.com
2643 wysh mlist '@any\e.where\e.example\e.com' # This is a comment
2644 wysh mlist $'@any\e\e\ex2Ewhere\e\e.example\e\e\e56com' # A comment
2645 wysh mlist "@any\e.where\e.example\e.com"
2649 In any event an unquoted backslash at the end of a command line is
2650 discarded and the next line continues the command.
2651 \*(ID Note that line continuation is handled before the above parsing is
2652 applied, i.e., the parsers documented above will see merged lines.
2653 Filenames, where expected, are subsequently subjected to the following
2654 transformations, in sequence:
2657 .Bl -bullet -compact -offset indent
2659 If the filename begins with an unquoted plus sign, and the
2661 variable is defined,
2662 the plus sign will be replaced by the value of the
2664 variable followed by a slash.
2667 variable is unset or is set to null, the filename will be unchanged.
2670 Meta expansions are applied to the filename: a leading tilde
2672 character will be replaced by the expansion of
2674 except when followed by a valid user name, in which case the home
2675 directory of the given user is used instead.
2680 will be replaced by the expansion of the variable, if possible; \*(UA
2681 .Sx "INTERNAL VARIABLES"
2684 (shell) variables can be accessed through this mechanism, and the usual
2685 escape mechanism has to be applied to prevent interpretation.
2686 If the fully expanded filename results in multiple pathnames and the
2687 command is expecting only one file, an error results.
2689 In interactive context, in order to allow simple value acceptance (via
2691 arguments will usually be displayed in a properly quoted form, e.g., a file
2692 .Ql diet\e is \ecurd.txt
2694 .Ql 'diet\e is \ecurd.txt' .
2698 The following commands are available:
2700 .Bl -tag -width ".Ic _ccount"
2707 ) command which follows.
2711 The comment-command causes the entire line to be ignored.
2713 this really is a normal command which' purpose is to discard its
2716 indicating special character, which means that, e.g., trailing comments
2717 on a line are not possible.
2721 Goes to the next message in sequence and types it
2727 Display the preceding message, or the n'th previous message if given
2728 a numeric argument n.
2732 Show the current message number (the
2737 Show a brief summary of commands.
2738 \*(OP Given an argument a synopsis for the command in question is
2739 shown instead; commands can be abbreviated in general and this command
2740 can be used to see the full expansion of an abbreviation including the
2741 synopsis, try, e.g.,
2746 and see how the output changes.
2756 Interprets the remainder of the word as a macro name and passes it
2761 is a shorter synonym for
2762 .Ql call Ar mymacro .
2766 (ac) Creates, selects or lists (an) account(s).
2767 Accounts are special incarnations of
2769 macros and group commands and variable settings which together usually
2770 arrange the environment for the purpose of creating an email account.
2771 Different to normal macros settings which are covered by
2773 \(en here by default enabled! \(en will not be reverted before the
2778 (case-insensitive) always exists, and all but it can be deleted via
2781 Without arguments a listing of all defined accounts is shown.
2782 With one argument the given account is activated: the system
2784 box of that account will be activated (as via
2786 and a possibly installed
2789 The two argument form is identical to defining a macro as via
2791 .Bd -literal -offset indent
2793 set folder=~/mail MAIL=+syste.mbox record=+sent.mbox
2794 set from='myname@myisp.example (My Name)'
2795 set smtp=smtp://mylogin@smtp.myisp.example
2801 (a) With no arguments, shows all currently-defined aliases.
2802 With one argument, shows that alias.
2803 With more than one argument,
2804 creates a new alias or appends to an existing one.
2806 can be used to delete aliases.
2810 (alt) Manage a list of alternate addresses / names of the active user,
2811 members of which will be removed from recipient lists when replying to
2814 variable is not set).
2815 If arguments are given the set of alternate names is replaced by them,
2816 without arguments the current set is displayed.
2820 Takes a message list and marks each message as having been answered.
2821 This mark has no technical meaning in the mail system;
2822 it just causes messages to be marked in the header summary,
2823 and makes them specially addressable.
2827 Calls a macro that has been created via
2832 (ch) Change the working directory to
2834 or the given argument.
2840 \*(OP Only applicable to S/MIME signed messages.
2841 Takes a message list and a file name and saves the certificates
2842 contained within the message signatures to the named file in both
2843 human-readable and PEM format.
2844 The certificates can later be used to send encrypted messages to the
2845 respective message senders by setting
2846 .Va smime-encrypt-USER@HOST
2851 (ch) Change the working directory to
2853 or the given argument.
2859 Only applicable to threaded mode.
2860 Takes a message list and makes all replies to these messages invisible
2861 in header summaries, unless they are in state
2867 \*(OP\*(NQ Manage colour mappings for the type of colour given as the
2868 (case-insensitive) first argument, which must be one of
2870 for 256-colour terminals,
2875 for the standard 8-colour ANSI / ISO 6429 color palette and
2879 for monochrome terminals.
2880 Monochrome terminals cannot deal with colours, but only (some) font
2884 Without further arguments the list of all currently defined mappings
2885 for the given colour type is shown (as a special case giving
2889 will iterate over all types in order).
2890 Otherwise the second argument defines the mappable slot, the third
2891 argument a (comma-separated list of) colour and font attribute
2892 specification(s), and the optional fourth argument can be used to
2893 specify a precondition: if conditioned mappings exist they are tested in
2894 (creation) order unless a (case-insensitive) match has been found, and
2895 the default mapping (if any has been established) will only be chosen as
2897 The types of precondition available depend on the mappable slot, the
2898 following of which exist:
2901 Mappings prefixed with
2903 are used for the \*(OPal builtin Mailx-Line-Editor (MLE, see
2904 .Sx "On terminal control and line editor" )
2905 and don't support preconditions.
2907 .Bl -tag -compact -width view-partinfo
2909 This mapping is used for the position indicator that is visible when
2910 a line cannot be fully displayed on the screen.
2917 Mappings prefixed with
2919 are used in header summaries, and they all understand the preconditions
2921 (the current message) and
2923 for elder messages (only honoured in conjunction with
2924 .Va datefield-markout-older ) .
2926 .Bl -tag -compact -width view-partinfo
2928 This mapping is used for the
2930 that can be created with the
2934 formats of the variable
2937 For the complete header summary line except the
2939 and the thread structure.
2941 For the thread structure which can be created with the
2943 format of the variable
2948 Mappings prefixed with
2950 are used when displaying messages.
2952 .Bl -tag -compact -width view-partinfo
2954 This mapping is used for so-called
2956 lines, which are MBOX file format specific header lines.
2959 A comma-separated list of headers to which the mapping applies may be
2960 given as a precondition; if the \*(OPal regular expression support is
2961 available then if any of the
2963 (extended) regular expression characters is seen the precondition will
2964 be evaluated as (an extended) one.
2966 For the introductional message info line.
2967 .It Cd view-partinfo
2968 For MIME part info lines.
2972 The following (case-insensitive) colour definitions and font attributes
2973 are understood, multiple of which can be specified in a comma-separated
2983 It is possible (and often applicable) to specify multiple font
2984 attributes for a single mapping.
2987 foreground colour attribute:
2997 To specify a 256-color mode a decimal number colour specification in
2998 the range 0 to 255, inclusive, is supported, and interpreted as follows:
3000 .Bl -tag -compact -width "999 - 999"
3002 the standard ISO 6429 colors, as above.
3004 high intensity variants of the standard colors.
3006 216 colors in tuples of 6.
3008 grayscale from black to white in 24 steps.
3010 .Bd -literal -offset indent
3012 fg() { printf "\e033[38;5;${1}m($1)"; }
3013 bg() { printf "\e033[48;5;${1}m($1)"; }
3015 while [ $i -lt 256 ]; do fg $i; i=$(($i + 1)); done
3016 printf "\e033[0m\en"
3018 while [ $i -lt 256 ]; do bg $i; i=$(($i + 1)); done
3019 printf "\e033[0m\en"
3023 background colour attribute (see
3025 for possible values).
3029 Mappings may be removed with the command
3031 For a generic overview see the section
3032 .Sx "Coloured display" .
3037 (C) Copy messages to files whose names are derived from the author of
3038 the respective message and don't mark them as being saved;
3039 otherwise identical to
3044 (c) Copy messages to the named file and don't mark them as being saved;
3045 otherwise identical to
3050 \*(NQ With no arguments, shows all currently-defined custom headers.
3051 With one argument, shows that custom header.
3052 With more than one argument, creates a new or replaces an existing
3053 custom header with the name given as the first argument, the content of
3054 which being defined by the concatenated remaining arguments.
3056 can be used to delete custom headers.
3057 \*(ID Overwriting of automatically managed headers is neither supported
3059 Defined custom headers will be injected into newly composed or forwarded
3062 .Dl customhdr OpenPGP id=12345678; url=http://www.YYY.ZZ
3066 may also be used to inject custom headers; it is covered by
3071 Show the name of the current working directory.
3075 \*(OP For unencrypted messages this command is identical to
3077 Encrypted messages are first decrypted, if possible, and then copied.
3081 \*(OP For unencrypted messages this command is identical to
3083 Encrypted messages are first decrypted, if possible, and then copied.
3087 Without arguments the current list of macros, including their content,
3088 is shown, otherwise a macro is defined.
3089 A macro definition is a sequence of commands in the following form:
3090 .Bd -literal -offset indent
3099 A defined macro can be invoked explicitly by using the
3103 commands, or implicitly if a macro hook is triggered, e.g., a
3105 Note that interpretation of
3107 depends on how (i.e.,
3109 normal macro, folder hook, hook, account switch) the macro is invoked.
3110 Macros can be deleted via
3114 Macro behaviour, including option localization, will change in v15.
3115 Please be aware of that and possibly embed a version check in a resource
3120 (d) Marks the given message list as
3122 Deleted messages will neither be saved in
3124 nor will they be available for most other commands.
3136 Deletes the current message and displays the next message.
3137 If there is no next message, \*(UA says
3144 up or down by one message when given
3148 argument, respectively.
3152 Takes a message list and marks each given message as a draft.
3153 This mark has no technical meaning in the mail system;
3154 it just causes messages to be marked in the header summary,
3155 and makes them specially addressable.
3159 (ec) Echoes its arguments after applying
3161 expansions and filename transformations, as documented for
3166 (e) Point the text editor (as defined in
3168 at each message from the given list in turn.
3169 Modified contents are discarded unless the
3176 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3177 conditional \(em if the condition of a preceding
3179 was false, check the following condition and execute the following block
3180 if it evaluates true.
3185 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3186 conditional \(em if none of the conditions of the preceding
3190 commands was true, the
3196 (en) Marks the end of an
3197 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3198 conditional execution block.
3203 \*(NQ \*(UA has a strict notion about which variables are
3204 .Sx "INTERNAL VARIABLES"
3205 and which are managed in the program
3207 Since some of the latter are a vivid part of \*(UAs functioning,
3208 however, they are transparently integrated into the normal handling of
3209 internal variables via
3213 To integrate other environment variables of choice into this
3214 transparent handling, and also to export internal variables into the
3215 process environment where they normally are not, a
3217 needs to become established with this command, as in, e.g.,
3220 .Dl environ link PERL5LIB from TZ
3223 Afterwards changing such variables with
3225 will cause automatic updates of the program environment, and therefore
3226 be inherited by newly created child processes.
3227 Sufficient system support provided (it was in BSD as early as 1987, and
3228 is standardized since Y2K) removing such variables with
3230 will remove them also from the program environment, but in any way
3231 the knowledge they ever have been
3234 Note this implies that
3236 may cause loss of links.
3241 will remove an existing link, but leaves the variables as such intact.
3242 Additionally the subcommands
3246 are provided, which work exactly the same as the documented commands
3250 but (additionally) link the variable(s) with the program environment and
3251 thus immediately export them to, or remove them from (if possible),
3252 respectively, the program environment.
3257 \*(OP Since \*(UA uses the console as a user interface it can happen
3258 that messages scroll by too fast to become recognized.
3259 Optionally an error message ring queue is available which stores
3260 duplicates of any error message and notifies the user in interactive
3261 sessions whenever a new error has occurred.
3262 The queue is finite: if its maximum size is reached any new message
3263 replaces the eldest.
3266 can be used to manage this message queue: if given
3268 or no argument the queue will be displayed and cleared,
3270 will only clear all messages from the queue.
3274 (ex or x) Exit from \*(UA without changing the active mailbox and skip
3275 any saving of messages in
3277 as well as a possibly tracked line editor history file.
3281 Show the list of features that have been compiled into \*(UA.
3282 (Outputs the contents of the variable
3289 but open the mailbox readonly.
3293 (fi) The file command switches to a new mailbox.
3294 Without arguments it shows status information of the current mailbox.
3295 If an argument is given, it will write out changes (such as deletions)
3296 the user has made and open a new mailbox.
3297 Some special conventions are recognized for the
3301 .Bl -tag -compact -offset indent -width ".Ar %:__lespec"
3303 (number sign) means the previous file,
3305 (percent sign) means the invoking user's system
3309 means the primary system mailbox of
3311 (and never the value of
3313 regardless of its actual setting),
3315 (ampersand) means the invoking user's
3325 expands to the same value as
3327 but the file is handled as a primary system mailbox by, e.g., the
3331 commands, meaning that messages that have been read in the current
3332 session will be moved to the
3334 mailbox instead of simply being flagged as read.
3337 If the name matches one of the strings defined with the command
3339 it is replaced by its long form and expanded.
3340 If the name ends with
3345 it is treated as being compressed with
3350 respectively, and transparently handled through an intermediate
3351 (un)compression step (using a temporary file) with the according
3352 facility, sufficient support provided.
3353 Likewise, if the named file doesn't exist, but a file with one of the
3354 mentioned compression extensions does, then the name is automatically
3355 expanded and the compressed file is used.
3357 Otherwise, if the name ends with an extension for which
3358 .Va file-hook-load-EXTENSION
3360 .Va file-hook-save-EXTENSION
3361 variables are set, then the given hooks will be used to load and save
3363 and \*(UA will work with an intermediate temporary file.
3365 MBOX files (flat file-based mailboxes) are generally locked during file
3366 operations in order to avoid inconsistencies due to concurrent
3368 \*(OPal Mailbox files which \*(UA treats as system
3370 boxes or primary mailboxes will also be protected by so-called dotlock
3371 files, the traditional way of mail spool file locking: for any file
3375 will be created for the duration of the synchronization \(em
3376 as necessary a privilege-separated dotlock child process will be used
3377 to accommodate for necessary privilege adjustments in order to create
3378 the dotlock file in the same directory
3379 and with the same user and group identities as the file of interest.
3382 for fine-tuning the handling of MBOX files.
3386 refers to a directory with the subdirectories
3391 then it is treated as a folder in
3393 format; \*(ID the variable
3395 can be used to control the format of yet non-existent folders.
3398 .Dl \*(IN protocol://[user[:password]@]host[:port][/path]
3399 .Dl \*(OU protocol://[user@]host[:port][/path]
3401 is taken as an Internet mailbox specification.
3402 The \*(OPally supported protocols are
3406 (POP3 with SSL/TLS encrypted transport).
3409 part is valid only for IMAP; there it defaults to
3411 Also see the section
3412 .Sx "On URL syntax and credential lookup" .
3416 contains special characters, in particular
3420 they must be escaped in URL notation \(en the command
3422 can be used to show the necessary conversion.
3426 Takes a message list and marks the messages as
3428 ged for urgent/special attention.
3429 This mark has no technical meaning in the mail system;
3430 it just causes messages to be highlighted in the header summary,
3431 and makes them specially addressable.
3440 With no arguments, list the names of the folders in the folder directory.
3441 With an existing folder as an argument,
3442 lists the names of folders below the named folder.
3448 but saves the message in a file named after the local part of the first
3449 recipient's address (instead of in
3456 but saves the message in a file named after the local part of the first
3457 recipient's address (instead of in
3464 but responds to all recipients regardless of the
3469 .It Ic followupsender
3472 but responds to the sender only regardless of the
3488 (f) Takes a list of message specifications and displays a summary of
3489 their message headers, as via
3491 An alias of this command is
3494 .Sx "Specifying messages" .
3500 but saves the message in a file named after the local part of the
3501 recipient's address (instead of in
3506 Takes a message and the address of a recipient
3507 and forwards the message to him.
3508 The text of the original message is included in the new one,
3509 with the value of the
3511 variable preceding it.
3516 commands specify which header fields are included in the new message.
3517 Only the first part of a multipart message is included unless the
3518 .Va forward-as-attachment
3522 is set recipient addresses will be stripped from comments, names etc.
3526 Specifies which header fields are to be ignored with the command
3528 This command has no effect when the
3529 .Va forward-as-attachment
3534 Specifies which header fields are to be retained with the command
3539 This command has no effect when the
3540 .Va forward-as-attachment
3545 Define or list command aliases, so-called ghosts.
3546 Without arguments a list of all currently known aliases is shown.
3547 With one argument the expansion of the given alias is shown.
3548 With two or more arguments a command alias is defined or updated: the
3549 first argument is the name under which the remaining command line should
3550 be accessible, the content of which can be just about anything.
3551 A ghost can be used everywhere a normal command can be used, but always
3552 takes precedence; any arguments that are given to the command alias are
3553 joined onto the alias content, and the resulting string forms the
3554 command line that is, in effect, executed.
3557 .Bd -literal -offset indent
3559 `ghost': no such alias: "xx"
3562 ghost xx "echo hello,"
3571 (h) Show the current group of headers, the size of which depends on
3574 and the style of which can be adjusted with the variable
3576 If a message-specification is given the group of headers containing the
3577 first message therein is shown and the message at the top of the screen
3592 the list of history entries;
3595 argument selects and shows the respective history entry \(en
3598 to accept it, and the history entry will become the new history top.
3599 The default mode if no arguments are given is
3606 Takes a message list and marks each message therein to be saved in the
3611 Does not override the
3614 \*(UA deviates from the POSIX standard with this command, because a
3616 command issued after
3618 will display the following message, not the current one.
3623 (i) Part of the nestable
3624 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3625 conditional execution construct \(em if the given condition is true then
3626 the encapsulated block is executed.
3627 POSIX only supports the (case-insensitive) conditions
3632 end, all remaining conditions are non-portable extensions; note that
3633 falsely specified conditions cause the execution of the entire
3634 conditional construct until the (matching) closing
3636 command to be suppressed.
3637 The syntax of the nestable
3639 conditional execution construct requires that each condition and syntax
3640 element is surrounded by whitespace.
3642 .Bd -literal -offset indent
3651 The (case-insensitive) condition
3653 erminal will evaluate to true if the standard input is a terminal, i.e.,
3654 in interactive sessions.
3655 Another condition can be any boolean value (see the section
3656 .Sx "INTERNAL VARIABLES"
3657 for textual boolean representations) to mark an enwrapped block as
3660 .Dq always execute .
3661 It is possible to check
3662 .Sx "INTERNAL VARIABLES"
3665 variables for existence or compare their expansion against a user given
3666 value or another variable by using the
3668 .Pf ( Dq variable next )
3669 conditional trigger character;
3670 a variable on the right hand side may be signalled using the same
3672 The variable names may be enclosed in a pair of matching braces.
3675 The available comparison operators are
3679 (less than or equal to),
3685 (greater than or equal to),
3689 (is substring of) and
3691 (is not substring of).
3692 The values of the left and right hand side are treated as strings and
3693 are compared 8-bit byte-wise, ignoring case according to the rules of
3694 the US-ASCII encoding (therefore, dependent on the active locale,
3695 possibly producing false results for strings in the locale encoding).
3696 Except for the substring checks the comparison will instead be performed
3697 arithmetically if both, the user given value as well as the variable
3698 content, can be parsed as numbers (integers).
3699 An unset variable is treated as the empty string.
3702 When the \*(OPal regular expression support is available, the additional
3708 They treat the right hand side as an extended regular expression that is
3709 matched case-insensitively and according to the active
3711 locale, meaning that strings in the locale encoding should be matched
3715 Conditions can be joined via AND-OR lists (where the AND operator is
3717 and the OR operator is
3719 which have equal precedence and will be evaluated with left
3720 associativity, thus using the same syntax that is known for the
3722 It is also possible to form groups of conditions and lists by enclosing
3723 them in pairs of brackets
3724 .Ql [\ \&.\&.\&.\ ] ,
3725 which may be interlocked within each other, and also be joined via
3729 The results of individual conditions and entire groups may be modified
3730 via unary operators: the unary operator
3732 will reverse the result.
3734 .Bd -literal -offset indent
3738 if $ttycharset == "UTF-8"
3739 echo *ttycharset* is set to UTF-8, case-insensitively
3743 echo These two variables are equal
3745 if $version-major >= 15
3746 echo Running a new version..
3747 if $features =@ "regex"
3748 if $TERM =~ "^xterm\&.*"
3749 echo ..in an X terminal
3752 if [ [ true ] && [ [ ${debug} ] || [ $verbose ] ] ]
3755 if true && $debug || ${verbose}
3756 echo Left associativity, as is known from the shell
3758 if ! ! true && ! [ ! $debug && ! $verbose ]
3759 echo Unary operator support
3767 Without arguments the list of ignored header fields is shown,
3768 otherwise the given list of header fields is added to the ignore list:
3769 Header fields in the ignore list are not shown on the terminal when
3770 a message is displayed.
3771 To display a message in its entirety, use the commands
3782 Shows the names of all available commands, alphabetically sorted.
3783 If given any non-whitespace argument the list will be shown in the order
3784 in which command prefixes are searched.
3787 output is available.
3791 This command can be used to localize changes to variables, meaning that
3792 their state will be reverted to the former one once the covered scope
3794 It can only be used inside of macro definition blocks introduced by
3798 and is interpreted as a boolean (string, see
3799 .Sx "INTERNAL VARIABLES" ) ;
3802 of an account is left once it is switched off again.
3803 .Bd -literal -offset indent
3804 define temporary_settings {
3819 enables change localization and calls
3821 which explicitly resets localization, then any value changes within
3823 will still be reverted by
3825 \*(ID Once the outermost level, the one which enabled localization
3826 first, is left, but no earlier, all adjustments will be unrolled.
3830 Reply to messages that come in via known
3833 .Pf ( Ic mlsubscribe )
3834 mailing lists, or pretend to do so (see
3835 .Sx "Mailing lists" ) :
3838 functionality this will actively resort and even remove message
3839 recipients in order to generate a message that is supposed to be sent to
3841 For example it will also implicitly generate a
3842 .Ql Mail-Followup-To:
3843 header if that seems useful, regardless of the setting of the variable
3850 but saves the message in a file named after the local part of the first
3851 recipient's address (instead of in
3856 (m) Takes a (list of) recipient address(es) as (an) argument(s),
3857 or asks on standard input if none were given;
3858 then collects the remaining mail content and sends it out.
3862 (mb) The given message list is to be sent to
3864 when \*(UA is quit; this is the default action unless the
3867 \*(ID This command can only be used in a primary system mailbox (see
3872 Without any arguments the content of the MIME type cache will displayed.
3873 Otherwise each argument defines a complete MIME type specification of
3874 a type that shall be added (prepended) to the cache.
3875 In any event MIME type sources are loaded first as necessary \(en
3876 .Va mimetypes-load-control
3877 can be used to fine-tune which sources are actually loaded.
3878 Refer to the section on
3879 .Sx "The mime.types files"
3880 for more on MIME type specifications and this topic in general.
3881 MIME type unregistration and cache resets can be triggered with
3886 Without arguments the list of all currently defined mailing lists
3887 (and their attributes, if any) is shown; a more verbose listing will be
3888 produced if either of
3893 Otherwise all given arguments (which need not be quoted except for
3894 whitespace) will be added and henceforth be recognized as mailing lists.
3895 Mailing lists may be removed via the command
3898 If the \*(OPal regular expression support is available then mailing
3899 lists may also be specified as (extended) regular expressions (see
3905 Without arguments the list of all currently defined mailing lists which
3906 have a subscription attribute is shown; a more verbose listing will be
3907 produced if either of
3912 Otherwise this attribute will be set for all given mailing lists,
3913 newly creating them as necessary (as via
3915 Subscription attributes may be removed via the command
3924 but moves the messages to a file named after the local part of the
3925 sender address of the first message (instead of in
3932 but marks the messages for deletion if they were transferred
3939 but also displays ignored header fields and all MIME parts.
3947 on the given messages, even in non-interactive mode and as long as the
3948 standard output is a terminal.
3954 \*(OP When used without arguments or if
3956 has been given the content of the
3958 cache is shown, loading it first as necessary,
3961 then the cache will only be initialized and
3963 will remove its contents.
3964 Note that \*(UA will try to load the file only once, use
3965 .Ql Ic \&\&netrc Ns \:\0\:clear
3966 to unlock further attempts.
3970 .Sx "On URL syntax and credential lookup" ;
3972 .Sx "The .netrc file"
3973 documents the file format in detail.
3977 Checks for new mail in the current folder without committing any changes
3979 If new mail is present, a message is shown.
3983 the headers of each new message are also shown.
3991 Goes to the next message in sequence and types it.
3992 With an argument list, types the next matching message.
4006 If the current folder is accessed via a network connection, a
4008 command is sent, otherwise no operation is performed.
4014 but also displays ignored header fields and all MIME parts.
4022 on the given messages, even in non-interactive mode and as long as the
4023 standard output is a terminal.
4031 but also pipes ignored header fields and all parts of MIME
4032 .Ql multipart/alternative
4037 (pi) Takes a message list and a shell command
4038 and pipes the messages through the command.
4039 Without an argument the current message is piped through the command
4046 every message is followed by a formfeed character.
4067 (q) Terminates the session, saving all undeleted, unsaved messages in
4070 preserving all messages marked with
4074 or never referenced in the system
4076 box, and removing all other messages from the primary system mailbox.
4077 If new mail has arrived during the session,
4079 .Dq You have new mail
4081 If given while editing a mailbox file with the command line flag
4083 then the edit file is rewritten.
4084 A return to the shell is effected,
4085 unless the rewrite of edit file fails,
4086 in which case the user can escape with the exit command.
4100 Removes the named files or directories.
4101 If a name refer to a mailbox, e.g., a Maildir mailbox, then a mailbox
4102 type specific removal will be performed, deleting the complete mailbox.
4103 The user is asked for confirmation in interactive mode.
4107 Takes the name of an existing folder
4108 and the name for the new folder
4109 and renames the first to the second one.
4110 Both folders must be of the same type.
4114 (R) Reply to originator.
4115 Does not reply to other recipients of the original message.
4117 will exchange this command with
4121 is set the recipient address will be stripped from comments, names etc.
4125 (r) Take a message and group-responds to it by addressing the sender
4128 .Va followup-to-honour ,
4131 .Va recipients-in-cc
4132 influence response behaviour.
4135 offers special support for replying to mailing lists.
4138 is set recipient addresses will be stripped from comments, names etc.
4151 but initiates a group-reply regardless of the value of
4158 but responds to the sender only regardless of the value of
4165 but does not add any header lines.
4166 This is not a way to hide the sender's identity,
4167 but useful for sending a message again to the same recipients.
4171 Takes a list of messages and a user name
4172 and sends each message to the named user.
4174 and related header fields are prepended to the new copy of the message.
4192 .It Ic respondsender
4198 (ret) Without arguments the list of retained header fields is shown,
4199 otherwise the given list of header fields is added to the retain list:
4200 Header fields in the retain list are shown on the terminal when
4201 a message is displayed, all other header fields are suppressed.
4202 To display a message in its entirety, use the commands
4211 takes precedence over the mentioned.
4217 but saves the messages in a file named after the local part of the
4218 sender of the first message instead of (in
4220 and) taking a filename argument.
4224 (s) Takes a message list and a filename and appends each message in turn
4225 to the end of the file.
4226 If no filename is given, the
4229 The filename in quotes, followed by the generated character count
4230 is echoed on the user's terminal.
4231 If editing a primary system mailbox the messages are marked for deletion.
4232 Filename interpretation as described for the
4234 command is performed.
4251 Header fields thus marked are filtered out when saving a message by
4253 or when automatically saving to
4255 This command should only be applied to header fields that do not contain
4256 information needed to decode the message,
4257 as MIME content fields do.
4269 Header fields thus marked are the only ones saved with a message when
4272 or when automatically saving to
4277 The use of this command is strongly discouraged since it may strip
4278 header fields that are needed to decode the message correctly.
4282 Takes a message specification (list) and displays a header summary of
4283 all matching messages, as via
4285 This command is an alias of
4288 .Sx "Specifying messages" .
4292 Takes a message list and marks all messages as having been read.
4296 (se) Without arguments this command shows all internal variables which
4297 are currently known to \*(UA (they have been set).
4298 A more verbose listing will be produced if either of
4302 are set, in which case variables may be preceded with a comment line
4303 that gives some context of what \*(UA knows about the given variable.
4305 Otherwise the given variables (and arguments) are set or adjusted.
4306 Arguments are of the form
4308 (no space before or after
4312 if there is no value, i.e., a boolean variable.
4313 Quotation marks may be placed around any part of the assignment
4314 statement to quote blanks or tabs, e.g.,
4316 .Dl set indentprefix='->'
4318 If an argument begins with
4322 the effect is the same as invoking the
4324 command with the remaining part of the variable
4325 .Pf ( Ql unset save ) .
4329 that is known to map to an environment variable will automatically cause
4330 updates in the program environment (unsetting a variable in the
4331 environment requires corresponding system support).
4332 Please use the command
4334 for further environmental control.
4339 .Sx "INTERNAL VARIABLES"
4345 (sh) Invokes an interactive version of the shell.
4349 Without arguments the list of all currently defined shortcuts is
4351 Otherwise all given arguments (which need not be quoted except for
4352 whitespace) are treated as pairs of shortcuts and their expansions,
4353 creating new or changing already existing shortcuts, as necessary.
4354 Shortcuts may be removed via the command
4356 The expansion strings should be in the syntax that has been described
4365 but performs neither MIME decoding nor decryption, so that the raw
4366 message text is shown.
4370 (si) Shows the size in characters of each message of the given
4375 Shows the current sorting criterion when used without an argument.
4376 Otherwise creates a sorted representation of the current folder,
4379 command and the addressing modes such that they refer to messages in
4381 Message numbers are the same as in regular mode.
4385 a header summary in the new order is also displayed.
4386 Automatic folder sorting can be enabled by setting the
4388 variable, as in, e.g.,
4389 .Ql set autosort=thread .
4390 Possible sorting criterions are:
4392 .Bl -tag -compact -offset indent -width "subject"
4394 Sort the messages by their
4396 field, that is by the time they were sent.
4398 Sort messages by the value of their
4400 field, that is by the address of the sender.
4403 variable is set, the sender's real name (if any) is used.
4405 Sort the messages by their size.
4407 \*(OP Sort the message by their spam score, as has been classified by
4410 Sort the messages by their message status.
4412 Sort the messages by their subject.
4414 Create a threaded display.
4416 Sort messages by the value of their
4418 field, that is by the address of the recipient.
4421 variable is set, the recipient's real name (if any) is used.
4426 (so) The source command reads commands from the given file, which is
4427 subject to the usual filename expansions (see introductional words of
4429 If the given argument ends with a vertical bar
4431 then the argument will instead be interpreted as a shell command and
4432 \*(UA will read the output generated by it.
4435 cannot be used from within macros that execute as
4436 .Va folder-hook Ns s
4439 i.e., it can only be called from macros that were
4446 (beside not supporting pipe syntax aka shell command input) is that
4447 this command will not generate an error if the given file argument
4448 cannot be opened successfully.
4449 This can matter in, e.g., resource files, since loading of those is
4450 stopped when an error is encountered.
4454 \*(OP Takes a list of messages and clears their
4460 \*(OP Takes a list of messages and causes the
4462 to forget it has ever used them to train its Bayesian filter.
4463 Unless otherwise noted the
4465 flag of the message is inspected to chose whether a message shall be
4473 \*(OP Takes a list of messages and informs the Bayesian filter of the
4477 This also clears the
4479 flag of the messages in question.
4483 \*(OP Takes a list of messages and rates them using the configured
4484 .Va spam-interface ,
4485 without modifying the messages, but setting their
4487 flag as appropriate; because the spam rating headers are lost the rate
4488 will be forgotten once the mailbox is left.
4489 Refer to the manual section
4491 for the complete picture of spam handling in \*(UA.
4495 \*(OP Takes a list of messages and sets their
4501 \*(OP Takes a list of messages and informs the Bayesian filter of the
4507 flag of the messages in question.
4516 Create a threaded representation of the current folder,
4517 i.\|e. indent messages that are replies to other messages in the header
4518 display and change the
4520 command and the addressing modes such that they refer to messages in the
4522 Message numbers are the same as in unthreaded mode.
4526 a header summary in threaded order is also displayed.
4530 (to) Takes a message list and displays the top few lines of each.
4531 The number of lines shown is controlled by the variable
4536 (tou) Takes a message list and marks the messages for saving in
4538 \*(UA deviates from the POSIX standard with this command,
4541 command will display the following message instead of the current one.
4547 but also displays out ignored header fields and all parts of MIME
4548 .Ql multipart/alternative
4553 (t) Takes a message list and types out each message on the user's
4559 For MIME multipart messages, all parts with a content type of
4563 are shown, the other are hidden except for their headers.
4564 Messages are decrypted and converted to the terminal character set
4569 Delete all given accounts.
4570 An error message is shown if a given account is not defined.
4573 will discard all existing accounts.
4577 (una) Takes a list of names defined by alias commands
4578 and discards the remembered groups of users.
4581 will discard all existing aliases.
4585 Takes a message list and marks each message as not having been answered.
4589 Only applicable to threaded mode.
4590 Takes a message list and makes the message and all replies to it visible
4591 in header summaries again.
4592 When a message becomes the current message,
4593 it is automatically made visible.
4594 Also when a message with collapsed replies is displayed,
4595 all of these are automatically uncollapsed.
4601 mapping for the given colour type (see
4603 for a list of types) and mapping; if the optional precondition argument
4604 is used then only the exact tuple of mapping and precondition is removed.
4607 will remove all mappings (no precondition allowed).
4609 .Sx "Coloured display"
4610 for the general picture.
4614 Deletes the custom headers given as arguments.
4617 will remove all custom headers.
4621 Undefine all given macros.
4622 An error message is shown if a given macro is not defined.
4625 will discard all existing macros.
4629 (u) Takes a message list and marks each message as not being deleted.
4633 Takes a message list and
4639 Takes a message list and marks each message as not being
4644 Removes the header field names from the list of ignored fields for the
4649 will remove all fields.
4653 Removes the header field names from the list of retained fields for the
4658 will remove all fields.
4662 Remove all the given command
4666 will remove all ghosts.
4670 Removes the header field names from the list of ignored fields.
4673 will remove all fields.
4677 Delete all given MIME types, e.g.,
4678 .Ql unmimetype text/plain
4679 will remove all registered specifications for the MIME type
4683 will discard all existing MIME types, just as will
4685 but which also reenables cache initialization via
4686 .Va mimetypes-load-control .
4690 Forget about all the given mailing lists.
4693 will remove all lists.
4698 .It Ic unmlsubscribe
4699 Remove the subscription attribute from all given mailing lists.
4702 will clear the attribute from all lists which have it set.
4713 Takes a message list and marks each message as not having been read.
4717 Removes the header field names from the list of retained fields.
4720 will remove all fields.
4724 Removes the header field names from the list of ignored fields for
4728 will remove all fields.
4732 Removes the header field names from the list of retained fields for
4736 will remove all fields.
4740 (uns) Takes a list of internal variable names and discards their
4741 remembered values; the reverse of
4748 Deletes the shortcut names given as arguments.
4751 will remove all shortcuts.
4755 Disable sorted or threaded mode
4761 return to normal message order and,
4765 displays a header summary.
4775 Decode the given URL-encoded string arguments and show the results.
4776 Note the resulting strings may not be valid in the current locale, see
4781 URL-encode the given arguments and show the results.
4782 Because the arguments effectively are in the character set of the
4783 current locale the results will vary accordingly unless the input solely
4784 consists of characters in the portable character set, see
4785 .Sx "Character sets" .
4789 Edit the values of or create the given variable(s) in the
4791 Boolean variables cannot be edited.
4795 This command produces the same output as the listing mode of
4799 ity adjustments, but only for the given variables.
4803 \*(OP Takes a message list and verifies each message.
4804 If a message is not a S/MIME signed message,
4805 verification will fail for it.
4806 The verification process checks if the message was signed using a valid
4808 if the message sender's email address matches one of those contained
4809 within the certificate,
4810 and if the message content has been altered.
4814 (v) Takes a message list and invokes the display editor on each message.
4815 Modified contents are discarded unless the
4821 (w) For conventional messages the body without all headers is written.
4822 The output is decrypted and converted to its native format as necessary.
4823 If the output file exists, the text is appended.
4824 If a message is in MIME multipart format its first part is written to
4825 the specified file as for conventional messages,
4826 and the user is asked for a filename to save each other part.
4827 For convience saving of each part may be skipped by giving an empty value;
4828 the same result can also be achieved by writing it to
4830 For the second and subsequent parts a leading
4832 character causes the part to be piped to the remainder of the user input
4833 interpreted as a shell command;
4834 otherwise the user input is expanded as usually for folders,
4835 e.g., tilde expansion is performed.
4836 In non-interactive mode, only the parts of the multipart message
4837 that have a filename given in the part header are written,
4838 the others are discarded.
4839 The original message is never marked for deletion in the originating
4842 the contents of the destination file are overwritten if the file
4844 No special handling of compressed files is performed.
4853 \*(UA presents message headers in windowfuls as described under the
4856 This command scrolls to the next window of messages.
4857 If an argument is given,
4858 it specifies the window to use.
4859 A number prefixed by
4863 indicates that the window is calculated in relation to the current position.
4864 A number without a prefix specifies an absolute window number,
4867 lets \*(UA scroll to the last window of messages.
4873 but scrolls to the next or previous window that contains at least one
4882 .\" .Sh TILDE ESCAPES {{{
4885 Here is a summary of the tilde escapes,
4886 which are used to perform special functions when composing messages.
4887 Tilde escapes are only recognized at the beginning of lines.
4890 is somewhat of a misnomer since the actual escape character can be
4891 changed by adjusting the option
4894 .Bl -tag -width ".Ic __ filename"
4897 Insert the string of text in the message prefaced by a single
4899 (If the escape character has been changed,
4900 that character must be doubled
4901 in order to send it at the beginning of a line.)
4904 .It Ic ~! Ar command
4905 Execute the indicated shell
4907 then return to the message.
4911 Same effect as typing the end-of-file character.
4914 .It Ic ~: Ar \*(UA-command Ns \0or Ic ~_ Ar \*(UA-command
4915 Execute the given \*(UA command.
4916 Not all commands, however, are allowed.
4920 Write a summary of command escapes.
4923 .It Ic ~< Ar filename
4928 .It Ic ~<! Ar command
4930 is executed using the shell.
4931 Its standard output is inserted into the message.
4934 .It Ic ~@ Op Ar filename...
4935 With no arguments, edit the attachment list interactively.
4936 If an attachment's file name is left empty,
4937 that attachment is deleted from the list.
4938 When the end of the attachment list is reached,
4939 \*(UA will ask for further attachments until an empty name is given.
4940 If a given file name solely consists of the number sign
4942 followed by a valid message number of the currently active mailbox, then
4943 the given message is attached as a MIME
4945 and the rest of this section does not apply.
4947 If character set conversion has been compiled into \*(UA, then this mode
4948 gives the user the option to specify input and output character sets,
4949 unless the file extension indicates binary content, in which case \*(UA
4950 asks whether this step shall be skipped for the attachment in question.
4951 If not skipped, then the charset that succeeds to represent the
4952 attachment data will be used in the
4954 MIME parameter of the mail message:
4956 .Bl -bullet -compact
4958 If input and output character sets are specified, then the conversion is
4959 performed on the fly.
4960 The user will be asked repeatedly until the desired conversion succeeds.
4962 If only an output character set is specified, then the input is assumed
4965 charset and will be converted to the given output charset on the fly.
4966 The user will be asked repeatedly until the desired conversion succeeds.
4968 If no character sets are specified at all then the algorithm that is
4969 documented in the section
4970 .Sx "Character sets"
4971 is applied, but directly and on the fly.
4972 The user will be asked repeatedly until the desired conversion succeeds.
4974 Finally, if an input-, but no output character set is specified, then no
4975 conversion is ever performed, but the
4977 MIME parameter value will still be set to the user input.
4979 The character set selection loop can be left by typing
4981 i.e., causing an interrupt.
4982 .\" \*(OU next sentence
4983 Note that before \*(UA version 15.0 this terminates the entire
4984 current attachment selection, not only the character set selection.
4987 Without character set conversion support, \*(UA will ask for the input
4988 character set only, and it'll set the
4990 MIME parameter value to the given input, if any;
4991 if no user input is seen then the
4993 character set will be used for the parameter value instead.
4994 Note that the file extension check isn't performed in this mode, since
4995 no conversion will take place anyway.
4997 Note that in non-interactive mode, for reproduceabilities sake, there
4998 will always be two questions for each attachment, regardless of whether
4999 character set conversion is available and what the file extension is.
5000 The first asks for the filename, and the second asks for the input
5001 character set to be passed through to the corresponding MIME parameter;
5002 no conversion will be tried if there is input to the latter question,
5003 otherwise the usual conversion algorithm, as above, is applied.
5004 For message attachments, the answer to the second question is completely
5009 arguments are specified for the
5011 command they are treated as a file list of
5013 -style quoted arguments, optionally also separated by commas, which are
5014 expanded and then appended to the existing list of message attachments.
5015 Message attachments can only be added via the first method.
5016 In this mode the (text) attachments are assumed to be in
5018 encoding, and will be evaluated as documented in the section
5019 .Sx "Character sets" .
5023 Inserts the string contained in the
5026 .Ql Ic ~i Ns \0Sign ) .
5027 The escape sequences tabulator
5035 Inserts the string contained in the
5038 .Ql Ic ~i Ns \0sign ) .
5039 The escape sequences tabulator
5046 .It Ic ~b Ar name ...
5047 Add the given names to the list of blind carbon copy recipients.
5050 .It Ic ~c Ar name ...
5051 Add the given names to the list of carbon copy recipients.
5055 Read the file specified by the
5057 variable into the message.
5061 Invoke the text editor on the message collected so far.
5062 After the editing session is finished,
5063 the user may continue appending text to the message.
5066 .It Ic ~F Ar messages
5067 Read the named messages into the message being sent, including all
5068 message headers and MIME parts.
5069 If no messages are specified, read in the current message.
5072 .It Ic ~f Ar messages
5073 Read the named messages into the message being sent.
5074 If no messages are specified, read in the current message.
5078 lists are used to modify the message headers.
5079 For MIME multipart messages,
5080 only the first displayable part is included.
5084 Edit the message header fields
5089 by typing each one in turn and allowing the user to edit the field.
5090 The default values for these fields originate from the
5098 Edit the message header fields
5104 by typing each one in turn and allowing the user to edit the field.
5107 .It Ic ~i Ar variable
5108 Insert the value of the specified variable into the message,
5109 adding a newline character at the end.
5110 The message remains unaltered if the variable is unset or empty.
5111 The escape sequences tabulator
5118 .It Ic ~M Ar messages
5119 Read the named messages into the message being sent,
5122 If no messages are specified, read the current message.
5125 .It Ic ~m Ar messages
5126 Read the named messages into the message being sent,
5129 If no messages are specified, read the current message.
5133 lists are used to modify the message headers.
5134 For MIME multipart messages,
5135 only the first displayable part is included.
5139 Display the message collected so far,
5140 prefaced by the message header fields
5141 and followed by the attachment list, if any.
5145 Abort the message being sent,
5146 copying it to the file specified by the
5153 .It Ic ~R Ar filename
5154 Read the named file into the message, indented by
5158 .It Ic ~r Ar filename
5159 Read the named file into the message.
5163 Cause the named string to become the current subject field.
5166 .It Ic ~t Ar name ...
5167 Add the given name(s) to the direct recipient list.
5170 .It Ic ~U Ar messages
5171 Read in the given / current message(s) excluding all headers, indented by
5175 .It Ic ~u Ar messages
5176 Read in the given / current message(s), excluding all headers.
5180 Invoke an alternate editor (defined by the
5182 option) on the message collected so far.
5183 Usually, the alternate editor will be a screen editor.
5184 After the editor is quit,
5185 the user may resume appending text to the end of the message.
5188 .It Ic ~w Ar filename
5189 Write the message onto the named file.
5191 the message is appended to it.
5197 except that the message is not saved at all.
5200 .It Ic ~| Ar command
5201 Pipe the message through the specified filter command.
5202 If the command gives no output or terminates abnormally,
5203 retain the original text of the message.
5206 is often used as a rejustifying filter.
5211 .\" .Sh INTERNAL VARIABLES {{{
5212 .Sh "INTERNAL VARIABLES"
5214 Internal \*(UA variables are controlled via the
5218 commands; prefixing a variable name with the string
5222 has the same effect as using
5228 Creation or editing of variables can be performed in the
5233 will give more insight on the given variable(s), and
5235 when called without arguments, will show a listing of all variables.
5236 Some well-known variables will also become inherited from the
5239 implicitly, others can be explicitly imported with the command
5241 and henceforth share the said properties.
5244 Two different kind of internal variables exist.
5245 There are boolean variables, which can only be in one of the two states
5249 and value variables with a(n optional) string value.
5250 For the latter proper quoting is necessary upon assignment time, the
5251 introduction of the section
5253 documents the supported quoting rules.
5255 .Bd -literal -offset indent
5256 wysh set one=val\e 1 two="val 2" \e
5257 three='val "3"' four=$'val \e'4\e''
5258 varshow one two three four
5259 unset one two three four
5263 Dependent upon the actual option the string values will be interpreted
5264 as numbers, colour names, normal text etc., but there also exists
5265 a special kind of string value, the
5266 .Dq boolean string ,
5267 which must either be a decimal integer (in which case
5271 and any other value is true) or any of the (case-insensitive) strings
5276 for a false boolean and
5281 for a true boolean; a special kind of boolean string is the
5283 which is a boolean string that can optionally be prefixed with the
5284 (case-insensitive) term
5288 which causes prompting of the user in interactive mode, with the given
5289 boolean as the default value.
5291 .\" .Ss "Initial settings" {{{
5292 .\" (Keep in SYNC: ./nail.h:okeys, ./nail.rc, ./nail.1:"Initial settings")
5293 .Ss "Initial Settings"
5295 The standard POSIX 2008/Cor 1-2013 mandates the following initial
5301 .Pf no Va autoprint ,
5315 .Pf no Va ignoreeof ,
5317 .Pf no Va keepsave ,
5319 .Pf no Va outfolder ,
5324 (note that \*(UA deviates from the standard by using
5328 special prompt escape results in
5336 .Pf no Va sendwait ,
5345 Notes: \*(UA doesn't support the
5347 variable \(en use command line options or
5348 .Va sendmail-arguments
5349 to pass options through to a MTA.
5350 And the default global
5352 file (which is loaded unless the
5354 command line flag has been used or the
5355 .Ev NAIL_NO_SYSTEM_RC
5356 environment variable is set) bends those initial settings a bit, e.g.,
5357 it sets the variables
5362 to name a few, calls
5364 etc., and should thus be taken into account.
5367 .\" .Ss "Variables" {{{
5370 .Bl -tag -width ".It Va _utoprin_"
5372 .It Va add-file-recipients
5373 \*(BO When file or pipe recipients have been specified,
5374 mention them in the corresponding address fields of the message instead
5375 of silently stripping them from their recipient list.
5376 By default such addressees are not mentioned.
5378 .Mx Va agent-shell-lookup
5379 .It Va agent-shell-lookup-USER@HOST , agent-shell-lookup-HOST , \
5381 \*(IN\*(OP Account passwords can be fetched via an external agent
5382 program in order to permit encrypted password storage \(en see
5383 .Sx "On URL syntax and credential lookup"
5384 for more on credential lookup.
5385 If this is set then the content is interpreted as a shell command the
5386 output of which (with newline characters removed) is treated as the
5387 account password shall the command succeed (and have produced non-empty
5388 non-newline output); e.g., via
5390 .Bd -literal -offset indent
5391 $ echo PASSWORD > .pass
5393 $ eval `gpg-agent --daemon \e
5394 --pinentry-program=/usr/bin/pinentry-curses \e
5395 --max-cache-ttl 99999 --default-cache-ttl 99999`
5396 $ echo 'set agent-shell-lookup="gpg -d .pass.gpg"' \e
5400 A couple of environment variables will be set for the agent:
5402 .Bl -tag -compact -width ".It Ev _AIL_TMPDIR[337]"
5404 The temporary directory that \*(UA uses.
5405 Usually identical to
5407 but guaranteed to be set and usable by child processes;
5408 to ensure the latter condition for
5414 for which the password is looked up.
5415 .It Ev NAIL_USER_ENC
5416 The URL percent-encoded variant of
5419 The plain machine hostname of the user account.
5420 .It Ev NAIL_HOST_PORT
5423 (hostname possibly including port) of the user account.
5428 \*(BO Causes only the local part to be evaluated
5429 when comparing addresses.
5433 \*(BO Causes messages saved in
5435 to be appended to the end rather than prepended.
5436 This should always be set.
5440 \*(BO Causes \*(UA to prompt for the subject of each message sent.
5441 If the user responds with simply a newline,
5442 no subject field will be sent.
5446 \*(BO Causes the prompts for
5450 lists to appear after the message has been edited.
5454 \*(BO If set, \*(UA asks for files to attach at the end of each message,
5455 shall the list be found empty at that time.
5456 An empty line finalizes the list.
5460 \*(BO Causes the user to be prompted for carbon copy recipients
5461 (at the end of each message if
5465 are set) shall the list be found empty (at that time).
5466 An empty line finalizes the list.
5470 \*(BO Causes the user to be prompted for blind carbon copy
5471 recipients (at the end of each message if
5475 are set) shall the list be found empty (at that time).
5476 An empty line finalizes the list.
5480 \*(BO\*(OP Causes the user to be prompted if the message is to be
5481 signed at the end of each message.
5484 variable is ignored when this variable is set.
5488 \*(BO Alternative name for
5495 .It Va attachment-ask-content-description , \
5496 attachment-ask-content-disposition , \
5497 attachment-ask-content-id , \
5498 attachment-ask-content-type
5499 \*(BO If set then the user will be prompted for some attachment
5500 information when editing the attachment list.
5501 It is advisable to not use these but for the first of the variables;
5502 even for that it has to be noted that the data is used
5508 A sequence of characters to display in the
5512 as shown in the display of
5514 each for one type of messages (see
5515 .Sx "Message states" ) ,
5516 with the default being
5519 .Ql NU\ \ *HMFAT+\-$~
5522 variable is set, in the following order:
5524 .Bl -tag -compact -offset indent -width ".It Ql _"
5546 start of a collapsed thread.
5548 an uncollapsed thread (TODO ignored for now).
5552 classified as possible spam.
5558 Specifies a list of recipients to which a blind carbon copy of each
5559 outgoing message will be sent automatically.
5563 Specifies a list of recipients to which a carbon copy of each outgoing
5564 message will be sent automatically.
5568 \*(BO Causes threads to be collapsed automatically when threaded mode
5575 \*(BO Causes the delete command to behave like
5577 thus, after deleting a message the next one will be typed automatically.
5581 \*(BO\*(OB Causes threaded mode (see the
5583 command) to be entered automatically when a folder is opened.
5585 .Ql autosort=thread .
5589 Causes sorted mode (see the
5591 command) to be entered automatically with the value of this option as
5592 sorting method when a folder is opened, e.g.,
5593 .Ql set autosort=thread .
5597 \*(BO Enables the substitution of
5599 by the contents of the last command line in shell escapes.
5602 .It Va batch-exit-on-error
5603 \*(BO If the batch mode has been enabled via the
5605 command line option, then this variable will be consulted whenever \*(UA
5606 completes one operation (returns to the command prompt); if it is set
5607 then \*(UA will terminate if the last operation generated an error.
5611 \*(BO Causes automatic display of a header summary after executing a
5617 \*(BO Sets some cosmetical features to traditional BSD style;
5618 has the same affect as setting
5620 and all other variables prefixed with
5622 it also changes the meaning of the \*(UA specific
5625 escape sequence and changes behaviour of
5627 (which doesn't exist in BSD).
5631 \*(BO Changes the letters shown in the first column of a header
5632 summary to traditional BSD style.
5636 \*(BO Changes the display of columns in a header summary to traditional
5641 \*(BO Changes some informational messages to traditional BSD style.
5647 field to appear immediately after the
5649 field in message headers and with the
5651 .Sx "TILDE ESCAPES" .
5655 The value that should appear in the
5659 MIME header fields when no character set conversion of the message data
5661 This defaults to US-ASCII, and the chosen character set should be
5662 US-ASCII compatible.
5666 \*(OP The default 8-bit character set that is used as an implicit last
5667 member of the variable
5669 This defaults to UTF-8.
5670 If no character set conversion capabilities are available in \*(UA then
5671 the only supported character set is
5673 Refer to the section
5674 .Sx "Character sets"
5675 for the complete picture of character set conversion in \*(UA.
5678 .It Va charset-unknown-8bit
5679 \*(OP RFC 1428 specifies conditions when internet mail gateways shall
5681 the content of a mail message by using a character set with the name
5683 Because of the unclassified nature of this character set \*(UA will not
5684 be capable to convert this character set to any other character set.
5685 If this variable is set any message part which uses the character set
5687 is assumed to really be in the character set given in the value,
5688 otherwise the (final) value of
5690 is used for this purpose.
5692 This variable will also be taken into account if a MIME type (see
5693 .Sx "The mime.types files" )
5694 of a MIME message part that uses the
5696 character set is forcefully treated as text.
5700 The default value for the
5705 .It Va colour-disable
5706 \*(BO\*(OP Forcefully disable usage of colours.
5707 Also see the section
5708 .Sx "Coloured display" .
5712 \*(BO\*(OP Whether colour shall be used for output that is paged through
5714 Note that pagers may need special flags, e.g.,
5722 in order to support colours.
5723 Often doing manual adjustments is unnecessary since \*(UA may perform
5724 adjustments dependend on the value of the environment variable
5726 (see there for more).
5730 In a(n interactive) terminal session, then if this valued option is set
5731 it'll be used as a threshold to determine how many lines the given
5732 output has to span before it will be displayed via the configured
5736 can be forced by setting this to the value
5738 setting it without a value will deduce the current height of the
5739 terminal screen to compute the treshold (see
5747 \*(OB A variable counterpart of the
5749 command (see there for documentation), interpreted as a comma-separated
5750 list of custom headers to be injected, to include commas in the header
5751 bodies escape them with backslash, e.g.:
5753 .Dl set customhdr='Hdr1: Body1-1\e, Body1-2, Hdr2: Body2'
5759 the message date, if any is to be displayed according to the format of
5761 is by default taken from the
5763 line of the message.
5764 If this variable is set the date as given in the
5766 header field is used instead, converted to local time.
5767 To control the display format of the date assign a valid
5772 format should not be used, because \*(UA doesn't take embedded newlines
5773 into account when calculating how many lines fit onto the screen.)
5775 .Va datefield-markout-older .
5778 .It Va datefield-markout-older
5779 This option, when set in addition to
5783 messages (concept is rather comparable to the
5785 option of the POSIX utility
5787 The content interpretation is identical to
5792 \*(BO Enables debug messages and obsoletion warnings, disables the
5793 actual delivery of messages and also implies
5799 .It Va disposition-notification-send
5801 .Ql Disposition-Notification-To:
5802 header (RFC 3798) with the message.
5806 .\" TODO .It Va disposition-notification-send-HOST
5808 .\".Va disposition-notification-send
5809 .\" for SMTP accounts on a specific host.
5810 .\" TODO .It Va disposition-notification-send-USER@HOST
5812 .\".Va disposition-notification-send
5813 .\"for a specific account.
5817 \*(BO When dot is set, a period
5819 on a line by itself during message input in (interactive) compose mode
5820 will be treated as end-of-message (in addition to the normal end-of-file
5829 .It Va dotlock-ignore-error
5830 \*(BO\*(OP Synchronization of mailboxes which \*(UA treats as system
5831 mailboxes (see the command
5833 will be protected with so-called dotlock files\(emthe traditional mail
5834 spool file locking method\(emin addition to system file locking.
5835 Because \*(UA ships with a privilege-separated dotlock creation program
5836 that should always be able to create such a dotlock file there is no
5837 good reason to ignore dotlock file creation errors, and thus these are
5838 fatal unless this variable is set.
5842 \*(BO If this variable is set then the editor is started automatically
5843 when a message is composed in interactive mode, as if the
5849 variable is implied for this automatically spawned editor session.
5853 \*(BO When a message is edited while being composed,
5854 its header is included in the editable text.
5864 fields are accepted within the header, other fields are ignored.
5868 \*(BO When entering interactive mode \*(UA normally writes
5869 .Dq \&No mail for user
5870 and exits immediately if a mailbox is empty or doesn't exist.
5871 If this option is set \*(UA starts even with an empty or nonexistent
5872 mailbox (the latter behaviour furtherly depends upon
5878 Suggestion for the MIME encoding to use in outgoing text messages
5880 Valid values are the default
5881 .Ql quoted-printable ,
5886 may cause problems when transferring mail messages over channels that
5887 are not ESMTP (RFC 1869) compliant.
5888 If there is no need to encode a message,
5890 transfer mode is always used regardless of this variable.
5891 Binary data is always encoded as
5896 If defined, the first character of this option
5897 gives the character to use in place of
5900 .Sx "TILDE ESCAPES" .
5904 If not set then file and command pipeline targets are not allowed,
5905 and any such address will be filtered out, giving a warning message.
5906 If set without a value then all possible recipient address
5907 specifications will be accepted \(en see the section
5908 .Sx "On sending mail, and non-interactive mode"
5910 To accept them, but only in interactive mode, or when tilde commands
5911 were enabled explicitly by using one of the command line options
5915 set this to the (case-insensitive) value
5917 (note right now this is actually like setting
5918 .Ql restrict,-all,+name,+addr ) .
5920 In fact the value is interpreted as a comma-separated list of values.
5923 then the existence of disallowed specifications is treated as a hard
5924 send error instead of only filtering them out.
5925 The remaining values specify whether a specific type of recipient
5926 address specification is allowed (optionally indicated by a plus sign
5928 prefix) or disallowed (prefixed with a hyphen
5932 addresses all possible address specifications,
5936 command pipeline targets,
5938 plain user names and (MTA) aliases (\*(OB
5940 may be used as an alternative syntax to
5945 These kind of values are interpreted in the given order, so that
5946 .Ql restrict,\:fail,\:+file,\:-all,\:+addr
5947 will cause hard errors for any non-network address recipient address
5948 unless \*(UA is in interactive mode or has been started with the
5952 command line option; in the latter case(s) any address may be used, then.
5956 Unless this variable is set additional mail-transfer-agent (MTA)
5957 arguments from the command line, as can be given after a
5959 separator, are ignored due to safety reasons.
5960 However, if set to the special (case-insensitive) value
5962 then the presence of additional MTA arguments is treated as a hard
5963 error that causes \*(UA to exit with failure status.
5964 A lesser strict variant is the otherwise identical
5966 which does accept such arguments in interactive mode, or if tilde
5967 commands were enabled explicitly by using one of the command line options
5974 \*(RO Information on the features compiled into \*(UA \(en the content
5975 of this variable is identical to the output of the command
5980 \*(BO This option reverses the meanings of a set of reply commands,
5981 turning the lowercase variants, which by default address all recipients
5982 included in the header of a message
5983 .Pf ( Ic reply , respond , followup )
5984 into the uppercase variants, which by default address the sender only
5985 .Pf ( Ic Reply , Respond , Followup )
5988 .Ic replysender , respondsender , followupsender
5990 .Ic replyall , respondall , followupall
5991 are not affected by the current setting of
5996 .It Va file-hook-load-EXTENSION , file-hook-save-EXTENSION
5997 It is possible to install file hooks which will be used by the
5999 command in order to be able to transparently handle (through an
6000 intermediate temporary file) files with specific
6002 s: the variable values can include shell snippets and are expected to
6003 write data to standard output / read data from standard input,
6005 \*(ID The variables may not be changed while there is a mailbox
6007 .Bd -literal -offset indent
6008 set file-hook-load-xy='echo >&2 XY-LOAD; gzip -cd' \e
6009 file-hook-save-xy='echo >&2 XY-SAVE; gzip -c' \e
6010 record=+null-sent.xy
6015 The default path under which mailboxes are to be saved:
6016 file names that begin with the plus-sign
6018 will be expanded by prefixing them with the value of this variable.
6019 The same special syntax conventions as documented for the
6021 command may be used; if the non-empty value doesn't start with a slash
6025 will be prefixed automatically.
6026 If unset or the empty string any
6028 prefixing file names will remain unexpanded.
6032 This variable can be set to the name of a
6034 macro which will be called whenever a
6037 The macro will also be invoked when new mail arrives,
6038 but message lists for commands executed from the macro
6039 only include newly arrived messages then.
6041 are activated by default in a folder hook, causing the covered settings
6042 to be reverted once the folder is left again.
6045 Macro behaviour, including option localization, will change in v15.
6046 Please be aware of that and possibly embed a version check in a resource
6050 .It Va folder-hook-FOLDER
6055 Unlike other folder specifications, the fully expanded name of a folder,
6056 without metacharacters, is used to avoid ambiguities.
6057 However, if the mailbox resides under
6061 specification is tried in addition, e.g., if
6065 (and thus relative to the user's home directory) then
6066 .Pa /home/usr1/mail/sent
6068 .Ql folder-hook-/home/usr1/mail/sent
6069 first, but then followed by
6070 .Ql folder-hook-+sent .
6074 \*(BO Controls whether a
6075 .Ql Mail-Followup-To:
6076 header is generated when sending messages to known mailing lists.
6078 .Va followup-to-honour
6080 .Ic mlist , mlsubscribe , reply
6085 .It Va followup-to-honour
6087 .Ql Mail-Followup-To:
6088 header is honoured when group-replying to a message via
6092 This is a quadoption; if set without a value it defaults to
6102 .It Va forward-as-attachment
6103 \*(BO Original messages are normally sent as inline text with the
6106 and only the first part of a multipart message is included.
6107 With this option messages are sent as unmodified MIME
6109 attachments with all of their parts included.
6113 The address (or a list of addresses) to put into the
6115 field of the message header, quoting RFC 5322:
6116 the author(s) of the message, that is, the mailbox(es) of the person(s)
6117 or system(s) responsible for the writing of the message.
6118 If replying to messages these addresses are handled as if they were in
6122 If the machine's hostname is not valid at the Internet (for example at
6123 a dialup machine) then either this variable or
6128 adds even more fine-tuning capabilities),
6132 contains more than one address,
6135 variable is required (according to the standard RFC 5322).
6139 \*(BO When replying to or forwarding a message \*(UA normally removes
6140 the comment and name parts of email addresses.
6141 If this variable is set such stripping is not performed,
6142 and comments, names etc. are retained.
6146 The string to put before the text of a message with the
6150 .Va forward-as-attachment
6153 .Dq -------- Original Message --------
6154 if unset; No heading is put if it is set to the empty string.
6158 \*(BO Causes the header summary to be written at startup and after
6159 commands that affect the number of messages or the order of messages in
6160 the current folder; enabled by default.
6161 The command line option
6169 A format string to use for the summary of
6171 similar to the ones used for
6174 Format specifiers in the given string start with a percent character
6176 and may be followed by an optional decimal number indicating the field
6177 width \(em if that is negative, the field is to be left-aligned.
6178 Valid format specifiers are:
6181 .Bl -tag -compact -offset indent -width "_%%_"
6183 A plain percent character.
6186 a space character but for the current message
6188 for which it expands to
6192 a space character but for the current message
6194 for which it expands to
6197 \*(OP The spam score of the message, as has been classified via the
6200 Shows only a replacement character if there is no spam support.
6202 Message attribute character (status flag); the actual content can be
6206 The date when the message was received, or the date found in the
6210 variable is set (optionally to a date display format string).
6212 The indenting level in threaded mode.
6214 The address of the message sender.
6216 The message thread tree structure.
6217 (Note that this format doesn't support a field width.)
6219 The number of lines of the message, if available.
6223 The number of octets (bytes) in the message, if available.
6225 Message subject (if any).
6227 Message subject (if any) in double quotes.
6229 Message recipient flags: is the addressee of the message a known or
6230 subscribed mailing list \(en see
6235 The position in threaded/sorted order.
6239 .Ql %>\&%a\&%m\ %-18f\ %16d\ %4l/%\-5o\ %i%-s ,
6241 .Ql %>\&%a\&%m\ %20-f\ \ %16d\ %3l/%\-5o\ %i%-S
6252 .It Va headline-bidi
6253 Bidirectional text requires special treatment when displaying headers,
6254 because numbers (in dates or for file sizes etc.) will not affect the
6255 current text direction, in effect resulting in ugly line layouts when
6256 arabic or other right-to-left text is to be displayed.
6257 On the other hand only a minority of terminals is capable to correctly
6258 handle direction changes, so that user interaction is necessary for
6260 Note that extended host system support is required nonetheless, e.g.,
6261 detection of the terminal character set is one precondition;
6262 and this feature only works in an Unicode (i.e., UTF-8) locale.
6264 In general setting this variable will cause \*(UA to encapsulate text
6265 fields that may occur when displaying
6267 (and some other fields, like dynamic expansions in
6269 with special Unicode control sequences;
6270 it is possible to fine-tune the terminal support level by assigning
6272 no value (or any value other than
6277 will make \*(UA assume that the terminal is capable to properly deal
6278 with Unicode version 6.3, in which case text is embedded in a pair of
6279 U+2068 (FIRST STRONG ISOLATE) and U+2069 (POP DIRECTIONAL ISOLATE)
6281 In addition no space on the line is reserved for these characters.
6283 Weaker support is chosen by using the value
6285 (Unicode 6.3, but reserve the room of two spaces for writing the control
6286 sequences onto the line).
6291 select Unicode 1.1 support (U+200E, LEFT-TO-RIGHT MARK); the latter
6292 again reserves room for two spaces in addition.
6296 \*(OP If a line editor is available then this can be set to
6297 name the (expandable) path of the location of a permanent history file.
6300 .It Va history-gabby
6301 \*(BO\*(OP Add more entries to the history as is normally done.
6304 .It Va history-gabby-persist
6305 \*(BO\*(OP \*(UA's own MLE will not save the additional
6307 entries in persistent storage unless this variable is set.
6308 On the other hand it will not loose the knowledge of whether
6309 a persistent entry was gabby or not.
6315 \*(OP If a line editor is available this value restricts the
6316 amount of history entries that are saved into a set and valid
6318 A value of less than 0 disables this feature;
6319 note that loading and incorporation of
6321 upon program startup can also be suppressed by doing this.
6322 If unset or 0, a default value will be used.
6323 Dependent on the available line editor this will also define the
6324 number of history entries in memory;
6325 it is also editor-specific whether runtime updates of this value will
6330 \*(BO This option is used to hold messages in the system
6332 box, and it is set by default.
6336 Use this string as hostname when expanding local addresses instead of
6337 the value obtained from
6348 transport is not used then it is normally the responsibility of the MTA
6349 to create these fields, \*(IN in conjunction with
6353 also influences the results;
6354 you should produce some test messages with the desired combination of
6363 \*(BO\*(OP Can be used to turn off the automatic conversion of domain
6364 names according to the rules of IDNA (internationalized domain names
6366 Since the IDNA code assumes that domain names are specified with the
6368 character set, an UTF-8 locale charset is required to represent all
6369 possible international domain names (before conversion, that is).
6373 \*(BO Ignore interrupt signals from the terminal while entering
6374 messages; instead echo them as
6376 characters and discard the current line.
6380 \*(BO Ignore end-of-file conditions
6381 .Pf ( Ql control-D )
6382 in compose mode on message input and in interactive command input.
6383 If set an interactive command input session can only be left by
6384 explicitly using one of the commands
6388 and message input in compose mode can only be terminated by entering
6391 on a line by itself or by using the
6393 .Sx "TILDE ESCAPES" ;
6395 overrides a setting of
6407 option for indenting messages,
6408 in place of the normal tabulator character
6410 which is the default.
6411 Be sure to quote the value if it contains spaces or tabs.
6415 \*(BO If set, an empty mailbox file is not removed.
6416 This may improve the interoperability with other mail user agents
6417 when using a common folder directory, and prevents malicious users
6418 from creating fake mailboxes in a world-writable spool directory.
6419 Note this only applies to local regular (MBOX) files, other mailbox
6420 types will never be removed.
6423 .It Va keep-content-length
6424 \*(BO When (editing messages and) writing
6426 mailbox files \*(UA can be told to keep the
6430 header fields that some MUAs generate by setting this variable.
6431 Since \*(UA does neither use nor update these non-standardized header
6432 fields (which in itself shows one of their conceptual problems),
6433 stripping them should increase interoperability in between MUAs that
6434 work with with same mailbox files.
6435 Note that, if this is not set but
6436 .Va writebackedited ,
6437 as below, is, a possibly performed automatic stripping of these header
6438 fields already marks the message as being modified.
6442 \*(BO When a message is saved it is usually discarded from the
6443 originating folder when \*(UA is quit.
6444 Setting this option causes all saved message to be retained.
6447 .It Va line-editor-disable
6448 \*(BO Turn off any enhanced line editing capabilities (see
6449 .Sx "On terminal control and line editor"
6454 \*(BO When a message is replied to and this variable is set,
6455 it is marked as having been answered.
6456 This mark has no technical meaning in the mail system;
6457 it just causes messages to be marked in the header summary,
6458 and makes them specially addressable.
6462 \*(BO \*(UA generates and expects fully RFC 4155 compliant MBOX text
6464 Messages which are fetched over the network or from within already
6465 existing Maildir (or any non-MBOX) mailboxes may require so-called
6467 quoting (insertion of additional
6469 characters to prevent line content misinterpretation) to be applied in
6470 order to be storable in MBOX mailboxes, however, dependent on the
6471 circumspection of the message producer.
6472 (E.g., \*(UA itself will, when newly generating messages, choose a
6473 .Pf Content-Transfer- Va encoding
6474 that prevents the necessity for such quoting \(en a necessary
6475 precondition to ensure message checksums won't change.)
6477 By default \*(UA will perform this
6479 quoting in a way that results in a MBOX file that is compatible with
6480 the POSIX MBOX layout, which means that, in order not to exceed the
6481 capabilities of simple applications, many more
6483 lines get quoted (thus modified) than necessary according to RFC 4155.
6484 Set this option to instead generate MBOX files which comply to RFC 4155.
6488 \*(BO Internal development variable.
6491 .It Va message-id-disable
6492 \*(BO By setting this option the generation of
6494 can be completely suppressed, effectively leaving this task up to the
6495 mail-transfer-agent (MTA) or the SMTP server.
6496 (According to RFC 5321 your SMTP server is not required to add this
6497 field by itself, so you should ensure that it accepts messages without a
6501 .It Va message-inject-head
6502 A string to put at the beginning of each new message.
6503 The escape sequences tabulator
6510 .It Va message-inject-tail
6511 A string to put at the end of each new message.
6512 The escape sequences tabulator
6520 \*(BO Usually, when an
6522 expansion contains the sender, the sender is removed from the expansion.
6523 Setting this option suppresses these removals.
6528 option to be passed to mail-transfer-agents (MTAs);
6529 though most of the modern MTAs don't (no longer) document this flag, no
6530 MTA is known which doesn't support it (for historical compatibility).
6533 .It Va mime-allow-text-controls
6534 \*(BO When sending messages, each part of the message is MIME-inspected
6535 in order to classify the
6538 .Ql Content-Transfer-Encoding:
6541 that is required to send this part over mail transport, i.e.,
6542 a computation rather similar to what the
6544 command produces when used with the
6548 This classification however treats text files which are encoded in
6549 UTF-16 (seen for HTML files) and similar character sets as binary
6550 octet-streams, forcefully changing any
6555 .Ql application/octet-stream :
6556 If that actually happens a yet unset charset MIME parameter is set to
6558 effectively making it impossible for the receiving MUA to automatically
6559 interpret the contents of the part.
6561 If this option is set, and the data was unambiguously identified as text
6562 data at first glance (by a
6566 file extension), then the original
6568 will not be overwritten.
6571 .It Va mime-alternative-favour-rich
6572 \*(BO If this variable is set then rich MIME alternative parts (e.g.,
6573 HTML) will be preferred in favour of included plain text versions when
6574 displaying messages, provided that a handler exists which produces
6575 output that can be (re)integrated into \*(UA's normal visual display.
6576 (E.g., at the time of this writing some newsletters ship their full
6577 content only in the rich HTML part, whereas the plain text part only
6578 contains topic subjects.)
6581 .It Va mime-counter-evidence
6584 field is used to decide how to handle MIME parts.
6585 Some MUAs however don't use
6587 or a similar mechanism to correctly classify content, but simply specify
6588 .Ql application/octet-stream ,
6589 even for plain text attachments like
6591 If this variable is set then \*(UA will try to classify such MIME
6592 message parts on its own, if possible, for example via a possibly
6593 existent attachment filename.
6594 A non-empty value may also be given, in which case a number is expected,
6595 actually a carrier of bits.
6596 Creating the bit-carrying number is a simple addition:
6597 .Bd -literal -offset indent
6598 ? !echo Value should be set to $((2 + 4 + 8))
6599 Value should be set to 14
6602 .Bl -bullet -compact
6604 If bit two is set (2) then the detected
6606 content-type will be carried along with the message and be used for
6608 .Va pipe-TYPE/SUBTYPE
6609 is responsible for the MIME part, shall that question arise;
6610 when displaying such a MIME part the part-info will indicate the
6611 overridden content-type by showing a plus-sign
6614 If bit three is set (4) then the counter-evidence is always produced
6615 and a positive result will be used as the MIME type, even forcefully
6616 overriding the parts given MIME type.
6618 If bit four is set (8) then as a last resort the actual content of
6619 .Ql application/octet-stream
6620 parts will be inspected, so that data which looks like plain text can be
6625 .It Va mimetypes-load-control
6626 This option can be used to control which of the
6628 databases are loaded by \*(UA, as furtherly described in the section
6629 .Sx "The mime.types files" .
6632 is part of the option value, then the user's personal
6634 file will be loaded (if it exists); likewise the letter
6636 controls loading of the system wide
6637 .Pa /etc/mime.types ;
6638 directives found in the user file take precedence, letter matching is
6640 If this option is not set \*(UA will try to load both files.
6641 Incorporation of the \*(UA-builtin MIME types cannot be suppressed,
6642 but they will be matched last.
6644 More sources can be specified by using a different syntax: if the
6645 value string contains an equals sign
6647 then it is instead parsed as a comma-separated list of the described
6650 pairs; the given filenames will be expanded and loaded, and their
6651 content may use the extended syntax that is described in the section
6652 .Sx "The mime.types files" .
6653 Directives found in such files always take precedence (are prepended to
6654 the MIME type cache).
6657 .It Va NAIL_EXTRA_RC
6658 The name of an optional startup file to be read last.
6659 This variable has an effect only if it is set in any of the
6660 .Sx "Resource files" ,
6661 it is not imported from the environment.
6662 Use this file for commands that are not understood by other POSIX
6667 .It Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup
6668 \*(BO\*(IN\*(OP Used to control usage of the users
6670 file for lookup of account credentials, as documented in the section
6671 .Sx "On URL syntax and credential lookup"
6675 .Sx "The .netrc file"
6676 documents the file format.
6680 If this variable has the value
6682 newly created local folders will be in Maildir format.
6686 Checks for new mail in the current folder each time the prompt is shown.
6687 A Maildir folder must be re-scanned to determine if new mail has arrived.
6688 If this variable is set to the special value
6690 then a Maildir folder will not be rescanned completely, but only
6691 timestamp changes are detected.
6695 .It Va on-compose-enter , on-compose-leave
6696 \*(ID Macro hooks which will be executed before compose mode is
6697 entered, and after composing has been finished, respectively.
6698 Please note that this interface is very likely to change in v15, and
6699 should therefore possibly even be seen as experimental.
6701 are by default enabled for these hooks, causing any setting to be
6702 forgotten after the message has been sent.
6703 The following variables will be set temporarily during execution of the
6706 .Bl -tag -compact -width ".It Va compose_subject"
6709 .It Va compose-sender
6711 .It Va compose-to , compose-cc , compose-bcc
6712 The list of receiver addresses as a space-separated list.
6713 .It Va compose-subject
6719 \*(BO Causes the filename given in the
6722 and the sender-based filenames for the
6726 commands to be interpreted relative to the directory given in the
6728 variable rather than to the current directory,
6729 unless it is set to an absolute pathname.
6733 \*(BO If set, each message feed through the command given for
6735 is followed by a formfeed character
6739 .It Va password-USER@HOST , password-HOST , password
6740 \*(IN Variable chain that sets a password, which is used in case none has
6741 been given in the protocol and account-specific URL;
6742 as a last resort \*(UA will ask for a password on the user's terminal if
6743 the authentication method requires a password.
6744 Specifying passwords in a startup file is generally a security risk;
6745 the file should be readable by the invoking user only.
6747 .It Va password-USER@HOST
6748 \*(OU (see the chain above for \*(IN)
6749 Set the password for
6753 If no such variable is defined for a host,
6754 the user will be asked for a password on standard input.
6755 Specifying passwords in a startup file is generally a security risk;
6756 the file should be readable by the invoking user only.
6760 \*(BO Send messages to the
6762 command without performing MIME and character set conversions.
6766 .It Va pipe-TYPE/SUBTYPE
6767 When a MIME message part of type
6769 (case-insensitive) is displayed or quoted,
6770 its text is filtered through the value of this variable interpreted as
6774 forces interpretation of the message part as plain text, e.g.,
6775 .Ql set pipe-application/xml=@
6776 will henceforth display XML
6778 (The same could also be achieved by adding a MIME type marker with the
6781 And \*(OPally MIME type handlers may be defined via
6782 .Sx "The Mailcap files"
6783 \(em corresponding flag strings are shown in parenthesis below.)
6788 can in fact be used to adjust usage and behaviour of a following shell
6789 command specification by appending trigger characters to it, e.g., the
6790 following hypothetical command specification could be used:
6791 .Bd -literal -offset indent
6792 set pipe-X/Y='@*!++=@vim ${NAIL_FILENAME_TEMPORARY}'
6796 .Bl -tag -compact -width ".It Ql __"
6798 Simply by using the special
6800 prefix the MIME type (shell command) handler will only be invoked to
6801 display or convert the MIME part if the message is addressed directly
6802 and alone by itself.
6803 Use this trigger to disable this and always invoke the handler
6804 .Pf ( Cd x-mailx-always ) .
6807 If set the handler will not be invoked when a message is to be quoted,
6808 but only when it will be displayed
6809 .Pf ( Cd x-mailx-noquote ) .
6812 The command will be run asynchronously, i.e., without blocking \*(UA,
6813 which may be a handy way to display a, e.g., PDF file while also
6814 continuing to read the mail message
6815 .Pf ( Cd x-mailx-async ) .
6816 Asynchronous execution implies
6820 The command must be run on an interactive terminal, \*(UA will
6821 temporarily release the terminal to it
6822 .Pf ( Cd needsterminal ) .
6823 This flag is mutual exclusive with
6825 will only be used in interactive mode and implies
6829 Request creation of a zero-sized temporary file, the absolute pathname
6830 of which will be made accessible via the environment variable
6831 .Ev NAIL_FILENAME_TEMPORARY
6832 .Pf ( Cd x-mailx-tmpfile ) .
6833 If this trigger is given twice then the file will be unlinked
6834 automatically by \*(UA when the command loop is entered again at latest
6835 .Pf ( Cd x-mailx-tmpfile-unlink ) .
6836 (Don't use this for asynchronous handlers.)
6839 Normally the MIME part content is passed to the handler via standard
6840 input; if this flag is set then the data will instead be written into
6841 .Ev NAIL_FILENAME_TEMPORARY
6842 .Pf ( Cd x-mailx-tmpfile-fill ) ,
6843 the creation of which is implied; note however that in order to cause
6844 deletion of the temporary file you still have to use two plus signs
6849 To avoid ambiguities with normal shell command content you can use
6850 another at-sign to forcefully terminate interpretation of remaining
6852 (Any character not in this list will have the same effect.)
6856 Some information about the MIME part to be displayed is embedded into
6857 the environment of the shell command:
6860 .Bl -tag -compact -width ".It Ev _AIL__ILENAME__ENERATED"
6863 The MIME content-type of the part, if known, the empty string otherwise.
6866 .It Ev NAIL_CONTENT_EVIDENCE
6868 .Va mime-counter-evidence
6869 includes the carry-around-bit (2), then this will be set to the detected
6870 MIME content-type; not only then identical to
6871 .Ev \&\&NAIL_CONTENT
6875 .It Ev NAIL_FILENAME
6876 The filename, if any is set, the empty string otherwise.
6879 .It Ev NAIL_FILENAME_GENERATED
6883 .It Ev NAIL_FILENAME_TEMPORARY
6884 If temporary file creation has been requested through the command prefix
6885 this variable will be set and contain the absolute pathname of the
6890 The temporary directory that \*(UA uses.
6891 Usually identical to
6893 but guaranteed to be set and usable by child processes;
6894 to ensure the latter condition for
6901 .It Va pipe-EXTENSION
6902 This is identical to
6903 .Va pipe-TYPE/SUBTYPE
6906 (normalized to lowercase using character mappings of the ASCII charset)
6907 names a file extension, e.g.,
6909 Handlers registered using this method take precedence.
6912 .It Va pop3-auth-USER@HOST , pop3-auth-HOST , pop3-auth
6913 \*(OP\*(IN Variable chain that sets the POP3 authentication method.
6914 The only possible value as of now is
6916 which is thus the default.
6919 .Mx Va pop3-bulk-load
6920 .It Va pop3-bulk-load-USER@HOST , pop3-bulk-load-HOST , pop3-bulk-load
6921 \*(BO\*(OP When accessing a POP3 server \*(UA loads the headers of
6922 the messages, and only requests the message bodies on user request.
6923 For the POP3 protocol this means that the message headers will be
6925 If this option is set then \*(UA will download only complete messages
6926 from the given POP3 server(s) instead.
6928 .Mx Va pop3-keepalive
6929 .It Va pop3-keepalive-USER@HOST , pop3-keepalive-HOST , pop3-keepalive
6930 \*(OP POP3 servers close the connection after a period of inactivity;
6931 the standard requires this to be at least 10 minutes,
6932 but practical experience may vary.
6933 Setting this variable to a numeric value greater than
6937 command to be sent each value seconds if no other operation is performed.
6940 .It Va pop3-no-apop-USER@HOST , pop3-no-apop-HOST , pop3-no-apop
6941 \*(BO\*(OP Unless this variable is set the
6943 authentication method will be used when connecting to a POP3 server that
6947 is that the password is not sent in clear text over the wire and that
6948 only a single packet is sent for the user/password tuple.
6950 .Va pop3-no-apop-HOST
6953 .Mx Va pop3-use-starttls
6954 .It Va pop3-use-starttls-USER@HOST , pop3-use-starttls-HOST , pop3-use-starttls
6955 \*(BO\*(OP Causes \*(UA to issue a
6957 command to make an unencrypted POP3 session SSL/TLS encrypted.
6958 This functionality is not supported by all servers,
6959 and is not used if the session is already encrypted by the POP3S method.
6961 .Va pop3-use-starttls-HOST
6965 .It Va print-alternatives
6966 \*(BO When a MIME message part of type
6967 .Ql multipart/alternative
6968 is displayed and it contains a subpart of type
6970 other parts are normally discarded.
6971 Setting this variable causes all subparts to be displayed,
6972 just as if the surrounding part was of type
6973 .Ql multipart/mixed .
6977 The string shown when a command is accepted.
6978 Prompting may be prevented by setting this to the null string
6980 .Pf no Va prompt ) .
6981 If a value is assigned the following \*(UA specific additional sequences
6988 is set, in which case it expands to
6992 is the default value of
6995 which will expand to
6997 if the last command failed and to
7001 which will expand to the name of the currently active
7003 if any, and to the empty string otherwise, and
7005 which will expand to the name of the currently active mailbox.
7006 (Note that the prompt buffer is size-limited, excess is cut off.)
7012 to encapsulate the expansions of the
7016 escape sequences as necessary to correctly display bidirectional text,
7017 this is not true for the final string that makes up
7019 as such, i.e., real BIDI handling is not supported.
7023 \*(BO Suppresses the printing of the version when first invoked.
7027 If set, \*(UA starts a replying message with the original message
7028 prefixed by the value of the variable
7030 Normally, a heading consisting of
7031 .Dq Fromheaderfield wrote:
7032 is put before the quotation.
7037 variable, this heading is omitted.
7040 is assigned, the headers selected by the
7041 .Ic ignore Ns / Ns Ic retain
7042 commands are put above the message body,
7045 acts like an automatic
7051 is assigned, all headers are put above the message body and all MIME
7052 parts are included, making
7054 act like an automatic
7057 .Va quote-as-attachment .
7060 .It Va quote-as-attachment
7061 \*(BO Add the original message in its entirety as a
7063 MIME attachment when replying to a message.
7064 Note this works regardless of the setting of
7069 \*(OP Can be set in addition to
7071 Setting this turns on a more fancy quotation algorithm in that leading
7072 quotation characters are compressed and overlong lines are folded.
7074 can be set to either one or two (space separated) numeric values,
7075 which are interpreted as the maximum (goal) and the minimum line length,
7076 respectively, in a spirit rather equal to the
7078 program, but line-, not paragraph-based.
7079 If not set explicitly the minimum will reflect the goal algorithmically.
7080 The goal can't be smaller than the length of
7082 plus some additional pad.
7083 Necessary adjustments take place silently.
7086 .It Va recipients-in-cc
7087 \*(BO On group replies, specify only the sender of the original mail in
7089 and mention the other recipients in the secondary
7091 By default all recipients of the original mail will be addressed via
7096 If defined, gives the pathname of the folder used to record all outgoing
7098 If not defined, then outgoing mail is not saved.
7099 When saving to this folder fails the message is not sent,
7100 but instead saved to
7104 .It Va record-resent
7105 \*(BO If both this variable and the
7112 commands save messages to the
7114 folder as it is normally only done for newly composed messages.
7117 .It Va reply-in-same-charset
7118 \*(BO If this variable is set \*(UA first tries to use the same
7119 character set of the original message for replies.
7120 If this fails, the mechanism described in
7121 .Sx "Character sets"
7122 is evaluated as usual.
7125 .It Va reply_strings
7126 Can be set to a comma-separated list of (case-insensitive according to
7127 ASCII rules) strings which shall be recognized in addition to the
7130 reply message indicators \(en builtin are
7132 which is mandated by RFC 5322, as well as the german
7137 A list of addresses to put into the
7139 field of the message header.
7140 Members of this list are handled as if they were in the
7145 .It Va reply-to-honour
7148 header is honoured when replying to a message via
7152 This is a quadoption; if set without a value it defaults to
7156 .It Va rfc822-body-from_
7157 \*(BO This variable can be used to force displaying a so-called
7159 line for messages that are embedded into an envelope mail via the
7161 MIME mechanism, for more visual convenience.
7165 \*(BO Enable saving of (partial) messages in
7167 upon interrupt or delivery error.
7171 When \*(UA initially displays the message headers it determines the
7172 number to display by looking at the speed of the terminal.
7173 The faster the terminal, the more will be shown.
7174 This option specifies the number to use and overrides the calculation.
7175 This number is also used for scrolling with the
7178 Overall screen dimensions and pager usage is influenced by the
7179 environment variables
7187 .It Va searchheaders
7188 \*(BO Expand message-list specifiers in the form
7190 to all messages containing the substring
7194 The string search is case insensitive.
7198 \*(OP A comma-separated list of character set names that can be used in
7199 outgoing internet mail.
7200 The value of the variable
7202 is automatically appended to this list of character-sets.
7203 If no character set conversion capabilities are compiled into \*(UA then
7204 the only supported charset is
7207 .Va sendcharsets-else-ttycharset
7208 and refer to the section
7209 .Sx "Character sets"
7210 for the complete picture of character set conversion in \*(UA.
7213 .It Va sendcharsets-else-ttycharset
7214 \*(BO\*(OP If this variable is set, but
7216 is not, then \*(UA acts as if
7218 had been set to the value of the variable
7220 In effect this combination passes through the message data in the
7221 character set of the current locale (given that
7223 hasn't been set manually), i.e., without converting it to the
7225 fallback character set.
7226 Thus, mail message text will be in ISO-8859-1 encoding when send from
7227 within a ISO-8859-1 locale, and in UTF-8 encoding when send from within
7229 If no character set conversion capabilities are available in \*(UA then
7230 the only supported character set is
7235 An address that is put into the
7237 field of outgoing messages, quoting RFC 5322: the mailbox of the agent
7238 responsible for the actual transmission of the message.
7239 This field should normally not be used unless the
7241 field contains more than one address, on which case it is required.
7244 address is handled as if it were in the
7250 To use an alternate mail transport agent (MTA),
7251 set this option to the full pathname of the program to use.
7252 It may be necessary to set
7253 .Va sendmail-progname
7256 The MTA will be passed command line arguments from several possible
7257 sources: from the variable
7258 .Va sendmail-arguments
7259 if set, from the command line if given and the variable
7262 Argument processing of the MTA will be terminated with a
7266 The otherwise occurring implicit usage of the following MTA command line
7267 arguments can be disabled by setting the boolean option
7268 .Va sendmail-no-default-arguments
7269 (which will also disable passing
7273 (for not treating a line with only a dot
7275 character as the end of input),
7283 option is set); in conjunction with the
7285 command line option \*(UA will also pass
7291 .It Va sendmail-arguments
7292 Arguments to pass through to the Mail-Transfer-Agent can be given via
7294 The content of this variable will be split up in a vector of arguments
7295 which will be joined onto other possible MTA options:
7297 .Dl set sendmail-arguments='-t -X \&"/tmp/my log\&"'
7300 .It Va sendmail-no-default-arguments
7301 \*(BO Unless this option is set \*(UA will pass some well known
7302 standard command line options to the defined
7304 program, see there for more.
7307 .It Va sendmail-progname
7308 Many systems use a so-called
7310 environment to ensure compatibility with
7312 This works by inspecting the name that was used to invoke the mail
7314 If this variable is set then the mailwrapper (the program that is
7315 actually executed when calling
7317 will treat its contents as that name.
7323 \*(BO When sending a message wait until the MTA (including the builtin
7324 SMTP one) exits before accepting further commands.
7326 with this variable set errors reported by the MTA will be recognizable!
7327 If the MTA returns a non-zero exit status,
7328 the exit status of \*(UA will also be non-zero.
7332 \*(BO Setting this option causes \*(UA to start at the last message
7333 instead of the first one when opening a mail folder.
7337 \*(BO Causes \*(UA to use the sender's real name instead of the plain
7338 address in the header field summary and in message specifications.
7342 \*(BO Causes the recipient of the message to be shown in the header
7343 summary if the message was sent by the user.
7347 A string for use with the
7353 A string for use with the
7359 Must correspond to the name of a readable file if set.
7360 The file's content is then appended to each singlepart message
7361 and to the first part of each multipart message.
7362 Be warned that there is no possibility to edit the signature for an
7366 .It Va skipemptybody
7367 \*(BO If an outgoing message does not contain any text in its first or
7368 only message part, do not send it but discard it silently (see also the
7374 \*(OP Specifies a directory with CA certificates in PEM (Privacy
7375 Enhanced Mail) format for verification of S/MIME signed messages.
7378 .It Va smime-ca-file
7379 \*(OP Specifies a file with CA certificates in PEM format for
7380 verification of S/MIME signed messages.
7383 .It Va smime-cipher-USER@HOST , smime-cipher
7384 \*(OP Specifies the cipher to use when generating S/MIME encrypted
7385 messages (for the specified account).
7386 RFC 5751 mandates a default of
7389 Possible values are (case-insensitive and) in decreasing cipher strength:
7397 (DES EDE3 CBC, 168 bits; default if
7399 isn't available) and
7403 The actually available cipher algorithms depend on the cryptographic
7404 library that \*(UA uses.
7405 \*(OP Support for more cipher algorithms may be available through
7406 dynamic loading via, e.g.,
7407 .Xr EVP_get_cipherbyname 3
7408 (OpenSSL) if \*(UA has been compiled to support this.
7411 .It Va smime-crl-dir
7412 \*(OP Specifies a directory that contains files with CRLs in PEM format
7413 to use when verifying S/MIME messages.
7416 .It Va smime-crl-file
7417 \*(OP Specifies a file that contains a CRL in PEM format to use when
7418 verifying S/MIME messages.
7421 .It Va smime-encrypt-USER@HOST
7422 \*(OP If this variable is set, messages send to the given receiver are
7423 encrypted before sending.
7424 The value of the variable must be set to the name of a file that
7425 contains a certificate in PEM format.
7427 If a message is sent to multiple recipients,
7428 each of them for whom a corresponding variable is set will receive an
7429 individually encrypted message;
7430 other recipients will continue to receive the message in plain text
7432 .Va smime-force-encryption
7434 It is recommended to sign encrypted messages, i.e., to also set the
7439 .It Va smime-force-encryption
7440 \*(BO\*(OP Causes \*(UA to refuse sending unencrypted messages.
7443 .It Va smime-no-default-ca
7444 \*(BO\*(OP Don't load default CA locations when verifying S/MIME signed
7449 \*(BO\*(OP S/MIME sign outgoing messages with the user's private key
7450 and include the user's certificate as a MIME attachment.
7451 Signing a message enables a recipient to verify that the sender used
7452 a valid certificate,
7453 that the email addresses in the certificate match those in the message
7454 header and that the message content has not been altered.
7455 It does not change the message text,
7456 and people will be able to read the message as usual.
7458 .Va smime-sign-cert , smime-sign-include-certs
7460 .Va smime-sign-message-digest .
7462 .Mx Va smime-sign-cert
7463 .It Va smime-sign-cert-USER@HOST , smime-sign-cert
7464 \*(OP Points to a file in PEM format.
7465 For the purpose of signing and decryption this file needs to contain the
7466 user's private key as well as his certificate.
7470 is always derived from the value of
7472 (or, if that contains multiple addresses,
7474 For the purpose of encryption the recipient's public encryption key
7475 (certificate) is expected; the command
7477 can be used to save certificates of signed messages (the section
7478 .Sx "Signed and encrypted messages with S/MIME"
7479 gives some details).
7480 This mode of operation is usually driven by the specialized form.
7482 When decrypting messages the account is derived from the recipient
7487 of the message, which are searched for addresses for which such
7489 \*(UA always uses the first address that matches,
7490 so if the same message is sent to more than one of the user's addresses
7491 using different encryption keys, decryption might fail.
7493 .Mx Va smime-sign-include-certs
7494 .It Va smime-sign-include-certs-USER@HOST , smime-sign-include-certs
7495 \*(OP If used, this is supposed to a consist of a comma-separated list
7496 of files, each of which containing a single certificate in PEM format to
7497 be included in the S/MIME message in addition to the
7500 This is most useful for long certificate chains if it is desired to aid
7501 the receiving party's verification process.
7502 Note that top level certificates may also be included in the chain but
7503 don't play a role for verification.
7505 .Va smime-sign-cert .
7506 Remember that for this
7508 refers to the variable
7510 (or, if that contains multiple addresses,
7513 .Mx Va smime-sign-message-digest
7514 .It Va smime-sign-message-digest-USER@HOST , smime-sign-message-digest
7515 \*(OP Specifies the message digest to use when signing S/MIME messages.
7516 RFC 5751 mandates a default of
7518 Possible values are (case-insensitive and) in decreasing cipher strength:
7526 The actually available message digest algorithms depend on the
7527 cryptographic library that \*(UA uses.
7528 \*(OP Support for more message digest algorithms may be available
7529 through dynamic loading via, e.g.,
7530 .Xr EVP_get_digestbyname 3
7531 (OpenSSL) if \*(UA has been compiled to support this.
7532 Remember that for this
7534 refers to the variable
7536 (or, if that contains multiple addresses,
7542 \*(OP Normally \*(UA invokes the program defined via
7544 to transfer messages, as described in
7545 .Sx "On sending mail, and non-interactive mode" .
7548 variable will instead cause SMTP network connections be made to the
7549 server specified therein in order to directly submit the message.
7550 \*(UA knows about three different
7551 .Dq SMTP protocols :
7553 .Bl -bullet -compact
7555 The plain SMTP protocol (RFC 5321) that normally lives on the
7556 server port 25 and requires setting the
7557 .Va smtp-use-starttls
7558 variable to enter a SSL/TLS encrypted session state.
7559 Assign a value like \*(IN
7560 .Ql [smtp://][user[:password]@]server[:port]
7562 .Ql [smtp://]server[:port] )
7563 to choose this protocol.
7565 Then the so-called SMTPS which is supposed to live on server port 465
7566 and is automatically SSL/TLS secured.
7567 Unfortunately it never became a standardized protocol and may thus not
7568 be supported by your hosts network service database
7569 \(en in fact the port number has already been reassigned to other
7572 SMTPS is nonetheless a commonly offered protocol and thus can be
7573 chosen by assigning a value like \*(IN
7574 .Ql smtps://[user[:password]@]server[:port]
7576 .Ql smtps://server[:port] ) ;
7577 due to the mentioned problems it is usually necessary to explicitly
7582 Finally there is the SUBMISSION protocol (RFC 6409), which usually
7583 lives on server port 587 and is practically identically to the SMTP
7584 protocol from \*(UA's point of view beside that; it requires setting the
7585 .Va smtp-use-starttls
7586 variable to enter a SSL/TLS secured session state.
7587 Assign a value like \*(IN
7588 .Ql submission://[user[:password]@]server[:port]
7590 .Ql submission://server[:port] ) .
7593 For more on credentials etc., please see
7594 .Sx "On URL syntax and credential lookup" .
7595 The SMTP transfer is executed in a child process, which runs
7596 asynchronously unless either the
7601 If it receives a TERM signal, it will abort and save the message to
7606 .It Va smtp-auth-USER@HOST , smtp-auth-HOST , smtp-auth
7607 \*(OP Variable chain that sets the SMTP authentication method.
7614 as well as the \*(OPal methods
7620 method doesn't need any user credentials,
7622 requires a user name and all other methods require a user name and
7630 .Va smtp-auth-password
7632 .Va smtp-auth-user ) .
7637 .Va smtp-auth-USER@HOST :
7638 may override dependent on sender address in the variable
7641 .It Va smtp-auth-password
7642 \*(OP\*(OU Sets the global fallback password for SMTP authentication.
7643 If the authentication method requires a password, but neither
7644 .Va smtp-auth-password
7646 .Va smtp-auth-password-USER@HOST
7648 \*(UA will ask for a password on the user's terminal.
7650 .It Va smtp-auth-password-USER@HOST
7652 .Va smtp-auth-password
7653 for specific values of sender addresses, dependent upon the variable
7656 .It Va smtp-auth-user
7657 \*(OP\*(OU Sets the global fallback user name for SMTP authentication.
7658 If the authentication method requires a user name, but neither
7661 .Va smtp-auth-user-USER@HOST
7663 \*(UA will ask for a user name on the user's terminal.
7665 .It Va smtp-auth-user-USER@HOST
7668 for specific values of sender addresses, dependent upon the variable
7672 .It Va smtp-hostname
7673 \*(IN Normally \*(UA uses the variable
7675 to derive the necessary
7677 information to issue a
7682 can be used to use the
7684 from the SMTP account
7691 from the content of this variable (or, if that is the empty string,
7693 or the local hostname as a last resort).
7694 This often allows using an address that is itself valid but hosted by
7695 a provider other than which (in
7697 is about to send the message.
7698 Setting this variable also influences the generated
7701 .Mx Va smtp-use-starttls
7702 .It Va smtp-use-starttls-USER@HOST , smtp-use-starttls-HOST , smtp-use-starttls
7703 \*(BO\*(OP Causes \*(UA to issue a
7705 command to make an SMTP session SSL/TLS encrypted, i.e., to enable
7706 transport layer security.
7710 .It Va spam-interface
7711 \*(OP In order to use any of the spam-related commands (like, e.g.,
7713 the desired spam interface must be defined by setting this variable.
7714 Please refer to the manual section
7716 for the complete picture of spam handling in \*(UA.
7717 All or none of the following interfaces may be available:
7719 .Bl -tag -width ".It Ql _ilte_"
7725 .Pf ( Lk http://spamassassin.apache.org SpamAssassin )
7727 Different to the generic filter interface \*(UA will automatically add
7728 the correct arguments for a given command and has the necessary
7729 knowledge to parse the program's output.
7732 will have been compiled into the \*(UA binary if
7737 Shall it be necessary to define a specific connection type (rather than
7738 using a configuration file for that), the variable
7740 can be used as in, e.g.,
7741 .Ql -d server.example.com -p 783 .
7742 It is also possible to specify a per-user configuration via
7744 Note that this interface doesn't inspect the
7746 flag of a message for the command
7750 \*(UA will directly communicate with the
7756 stream socket as specified in
7758 It is possible to specify a per-user configuration via
7762 generic spam filter support via freely configurable hooks.
7763 This interface is meant for programs like
7767 and requires according behaviour in respect to the hooks' exit
7768 status for at least the command
7771 meaning a message is spam,
7775 for unsure and any other return value indicating a hard error);
7776 since the hooks can include shell code snippets diverting behaviour
7777 can be intercepted as necessary.
7779 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
7782 .Va spamfilter-spam ;
7785 contains examples for some programs.
7786 The process environment of the hooks will have the variables
7787 .Ev NAIL_TMPDIR , TMPDIR
7789 .Ev NAIL_FILENAME_GENERATED
7791 Note that spam score support for
7793 isn't supported unless the \*(OPtional regular expression support is
7795 .Va spamfilter-rate-scanscore
7802 \*(OP Messages that exceed this size won't be passed through to the
7804 .Va spam-interface .
7805 If unset or 0, the default of 420000 bytes is used.
7808 .It Va spamc-command
7809 \*(OP The path to the
7813 .Va spam-interface .
7814 Note that the path is not expanded, but used
7816 A fallback path will have been compiled into the \*(UA binary if the
7817 executable had been found during compilation.
7820 .It Va spamc-arguments
7821 \*(OP Even though \*(UA deals with most arguments for the
7824 automatically, it may at least sometimes be desirable to specify
7825 connection-related ones via this variable, e.g.,
7826 .Ql -d server.example.com -p 783 .
7830 \*(OP Specify a username for per-user configuration files for the
7832 .Va spam-interface .
7833 If this is set to the empty string then \*(UA will use the name of the
7839 \*(OP Specify the path of the
7841 domain socket on which
7843 listens for connections for the
7845 .Va spam-interface .
7846 Note that the path is not expanded, but used
7851 \*(OP Specify a username for per-user configuration files for the
7853 .Va spam-interface .
7854 If this is set to the empty string then \*(UA will use the name of the
7863 .It Va spamfilter-ham , spamfilter-noham , \
7864 spamfilter-nospam , spamfilter-rate , spamfilter-spam
7865 \*(OP Command and argument hooks for the
7867 .Va spam-interface .
7870 contains examples for some programs.
7873 .It Va spamfilter-rate-scanscore
7874 \*(OP Because of the generic nature of the
7877 spam scores are not supported for it by default, but if the \*(OPtional
7878 regular expression support is available then setting this variable can
7879 be used to overcome this restriction.
7880 It is interpreted as follows: first a number (digits) is parsed that
7881 must be followed by a semicolon
7883 and an extended regular expression.
7884 Then the latter is used to parse the first output line of the
7886 hook, and, in case the evaluation is successful, the group that has been
7887 specified via the number is interpreted as a floating point scan score.
7891 \*(OP Specifies a directory with CA certificates in PEM (Pricacy
7892 Enhanced Mail) for verification of of SSL/TLS server certificates.
7894 .Xr SSL_CTX_load_verify_locations 3
7895 for more information.
7899 \*(OP Specifies a file with CA certificates in PEM format for
7900 verification of SSL/TLS server certificates.
7902 .Xr SSL_CTX_load_verify_locations 3
7903 for more information.
7906 .It Va ssl-cert-USER@HOST , ssl-cert-HOST , ssl-cert
7907 \*(OP Variable chain that sets the file name for a SSL/TLS client
7908 certificate required by some servers.
7909 This is a direct interface to the
7913 function of the OpenSSL library, if available.
7915 .Mx Va ssl-cipher-list
7916 .It Va ssl-cipher-list-USER@HOST , ssl-cipher-list-HOST , ssl-cipher-list
7917 \*(OP Specifies a list of ciphers for SSL/TLS connections.
7918 This is a direct interface to the
7922 function of the OpenSSL library, if available; see
7924 for more information.
7925 By default \*(UA doesn't set a list of ciphers, which in effect will use a
7927 specific cipher (protocol standards ship with a list of acceptable
7928 ciphers), possibly cramped to what the actually used SSL/TLS library
7929 supports \(en the manual section
7930 .Sx "An example configuration"
7931 also contains a SSL/TLS use case.
7934 .It Va ssl-config-file
7935 \*(OP If this variable is set \*(UA will call
7936 .Xr CONF_modules_load_file 3
7937 to allow OpenSSL to be configured according to the host system wide
7939 If a non-empty value is given then this will be used to specify the
7940 configuration file to be used instead of the global OpenSSL default;
7941 note that in this case it is an error if the file cannot be loaded.
7942 The application name will always be passed as
7947 \*(OP Specifies a file that contains a CRL in PEM format to use when
7948 verifying SSL/TLS server certificates.
7952 \*(OP Specifies a directory that contains files with CRLs in PEM format
7953 to use when verifying SSL/TLS server certificates.
7956 .It Va ssl-key-USER@HOST , ssl-key-HOST , ssl-key
7957 \*(OP Variable chain that sets the file name for the private key of
7958 a SSL/TLS client certificate.
7959 If unset, the name of the certificate file is used.
7960 The file is expected to be in PEM format.
7961 This is a direct interface to the
7965 function of the OpenSSL library, if available.
7968 .It Va ssl-method-USER@HOST , ssl-method-HOST , ssl-method
7970 \*(OB Please use the newer and more flexible
7972 instead: if both values are set,
7974 will take precedence!
7975 Can be set to the following values, the actually used
7977 specification to which it is mapped is shown in parenthesis:
7979 .Pf ( Ql -ALL, TLSv1.2 ) ,
7981 .Pf ( Ql -ALL, TLSv1.1 ) ,
7983 .Pf ( Ql -ALL, TLSv1 )
7986 .Pf ( Ql -ALL, SSLv3 ) ;
7991 and thus includes the SSLv3 protocol.
7992 Note that SSLv2 is no longer supported at all.
7995 .It Va ssl-no-default-ca
7996 \*(BO\*(OP Don't load default CA locations to verify SSL/TLS server
8000 .It Va ssl-protocol-USER@HOST , ssl-protocol-HOST , ssl-protocol
8001 \*(OP Specify the used SSL/TLS protocol.
8002 This is a direct interface to the
8006 function of the OpenSSL library, if available;
8007 otherwise an \*(UA internal parser is used which understands the
8008 following subset of (case-insensitive) command strings:
8014 as well as the special value
8016 Multiple specifications may be given via a comma-separated list which
8017 ignores any whitespace.
8020 plus prefix will enable a protocol, a
8022 minus prefix will disable it, so that
8024 will enable only the TLSv1.2 protocol.
8026 It depends upon the used TLS/SSL library which protocols are actually
8027 supported and which protocols are used if
8029 is not set, but note that SSLv2 is no longer supported at all and
8031 Especially for older protocols explicitly securing
8033 may be worthwile, see
8034 .Sx "An example configuration" .
8038 \*(OP Gives the pathname to an entropy daemon socket, see
8040 Not all SSL/TLS libraries support this.
8043 .It Va ssl-rand-file
8044 \*(OP Gives the filename to a file with random entropy data, see
8045 .Xr RAND_load_file 3 .
8046 If this variable is not set, or set to the empty string, or if the
8047 filename expansion failed, then
8048 .Xr RAND_file_name 3
8049 will be used to create the filename if, and only if,
8051 documents that the SSL PRNG is not yet sufficiently seeded.
8052 If \*(UA successfully seeded the SSL PRNG then it'll update the file via
8053 .Xr RAND_write_file 3 .
8054 This variable is only used if
8056 is not set (or not supported by the SSL/TLS library).
8059 .It Va ssl-verify-USER@HOST , ssl-verify-HOST , ssl-verify
8060 \*(OP Variable chain that sets the action to be performed if an error
8061 occurs during SSL/TLS server certificate validation.
8062 Valid (case-insensitive) values are
8064 (fail and close connection immediately),
8066 (ask whether to continue on standard input),
8068 (show a warning and continue),
8070 (do not perform validation).
8076 If only set without an assigned value, then this option inhibits the
8081 header fields that include obvious references to \*(UA.
8082 There are two pitfalls associated with this:
8083 First, the message id of outgoing messages is not known anymore.
8084 Second, an expert may still use the remaining information in the header
8085 to track down the originating mail user agent.
8090 suppression doesn't occur.
8095 (\*(OP) This specifies a comma-separated list of
8100 .Sx "On terminal control and line editor" ,
8101 escape commas with backslash) to be used to overwrite or define entries.
8103 that this variable will only be queried once at program startup and can
8104 thus only be specified in resource files or on the command line.
8107 String capabilities form
8109 pairs and are expected unless noted otherwise.
8110 Numerics have to be notated as
8112 where the number is expected in normal decimal notation.
8113 Finally, booleans don't have any value but indicate a true or false
8114 state simply by being defined or not; this indeed means that \*(UA
8115 doesn't support undefining a boolean that normally exists.
8116 The following example defines that the terminal has 256 colours:
8118 .Bd -literal -offset indent
8119 set termcap="colors=256"
8123 Keycodes can easily be detected with the command
8125 by running it on an interactive terminal via
8129 command line option if available) and pressing some keys: here
8137 (actually a visualized numeric where
8139 stands for 1 etc.; in fact: the numeric value of
8141 in the US-ASCII character set bitwise XORd with
8144 .Ql $ echo $((0x41 ^ 0x40)) .
8147 and other control characters have to be notated as shell-style
8148 escape sequences, e.g.,
8158 The following terminal capabilities are or may be meaningful for the
8159 operation of the builtin line editor or \*(UA in general:
8162 .Bl -tag -compact -width yay
8164 .It Cd colors Ns \0or Cd Co
8166 numeric capability specifying the maximum number of colours.
8167 Note that \*(UA doesn't actually care about the terminal beside that,
8168 but always emits ANSI/ISO 6429 escape sequences for producing the
8169 colour and font attributes.
8172 .It Cd rmcup Ns \0or Cd te Ns \0/ Cd smcup Ns \0or Cd ti
8176 respectively: exit and enter the alternative screen
8178 effectively turning \*(UA into a fullscreen application.
8179 To disable that, set (at least) one to the empty string.
8181 .It Cd smkx Ns \0or Cd ks Ns \0/ Cd rmkx Ns \0or Cd ke
8185 respectively: enable and disable the keypad.
8186 This is always enabled if available, because it seems even keyboards
8187 without keypads generate other key codes for, e.g., cursor keys in that
8188 case, and only if enabled we see the codes that we are interested in.
8190 .It Cd ed Ns \0or Cd cd
8194 .It Cd clear Ns \0or Cd cl
8196 clear the screen and home cursor.
8197 (Will be simulated via
8202 .It Cd home Ns \0or Cd ho
8207 .It Cd el Ns \0or Cd ce
8209 clear to the end of line.
8210 (Will be simulated via
8212 plus repetitions of space characters.)
8214 .It Cd hpa Ns \0or Cd ch
8215 .Cd column_address :
8216 move the cursor (to the given column parameter) in the current row.
8217 (Will be simulated via
8223 .Cd carriage_return :
8224 move to the first column in the current row.
8225 The default builtin fallback is
8228 .It Cd cub1 Ns \0or Cd le
8230 move the cursor left one space (non-destructively).
8231 The default builtin fallback is
8234 .It Cd cuf1 Ns \0or Cd nd
8236 move the cursor right one space (non-destructively).
8237 The default builtin fallback is
8239 which is used by most terminals.
8248 .It Va termcap-disable
8249 \*(OP Disable any interaction with a terminal control library.
8250 If set only some generic fallback builtins and possibly the content of
8252 describe the terminal to \*(UA.
8254 that this variable will only be queried once at program startup and can
8255 thus only be specified in resource files or on the command line.
8259 If defined, gives the number of lines of a message to be displayed
8262 normally, the first five lines are printed.
8266 The character set of the terminal \*(UA operates on,
8267 and the one and only supported character set that \*(UA can use if no
8268 character set conversion capabilities have been compiled into it,
8269 in which case it defaults to ISO-8859-1 unless it can deduce a value
8273 Refer to the section
8274 .Sx "Character sets"
8275 for the complete picture about character sets.
8278 .It Va user-HOST , user
8279 \*(IN Variable chain that sets a global fallback user name, which is
8280 used in case none has been given in the protocol and account-specific
8282 This variable defaults to the name of the user who runs \*(UA.
8286 \*(BO Setting this option enables upward compatibility with \*(UA
8287 version 15.0 in respect to which configuration options are available and
8288 how they are handled.
8289 This manual uses \*(IN and \*(OU to refer to the new and the old way of
8290 doing things, respectively.
8294 \*(BO Setting this option, also controllable via the command line option
8296 causes \*(UA to be more verbose, e.g., it will display obsoletion
8297 warnings and SSL/TLS certificate chains.
8298 Even though marked \*(BO this option may be set twice in order to
8299 increase the level of verbosity even more, in which case even details of
8300 the actual message delivery and protocol conversations are shown.
8303 is sufficient to disable verbosity as such.
8309 .It Va version , version-major , version-minor , version-update
8310 \*(RO \*(UA version information: the first variable contains a string
8311 containing the complete version identification \(en this is identical to
8312 the output of the command
8314 The latter three contain only digits: the major, minor and update
8318 .It Va writebackedited
8319 If this variable is set messages modified using the
8323 commands are written back to the current folder when it is quit;
8324 it is only honoured for writable folders in MBOX format, though.
8325 Note that the editor will be pointed to the raw message content in that
8326 case, i.e., neither MIME decoding nor decryption will have been
8327 performed, and proper RFC 4155
8329 quoting of newly added or edited content is also left as an excercise to
8333 .\" }}} (INTERNAL VARIABLES)
8336 .\" .Sh ENVIRONMENT {{{
8340 .Dq environment variable
8341 should be considered an indication that these variables are either
8342 standardized as vivid parts of process environments, or that they are
8343 commonly found in there.
8344 The process environment is inherited from the
8346 once \*(UA is started, and unless otherwise explicitly noted handling of
8347 the following variables transparently integrates into that of the
8348 .Sx "INTERNAL VARIABLES"
8349 from \*(UA's point of view.
8350 This means that, e.g., they can be managed via
8354 causing automatic program environment updates (to be inherited by
8355 newly created child processes).
8358 In order to transparently integrate other environment variables equally
8359 they need to be imported (linked) with the command
8361 This command can also be used to set and unset non-integrated
8362 environment variables from scratch, sufficient system support provided.
8363 The following example, applicable to a POSIX shell, sets the
8365 environment variable for \*(UA only, and beforehand exports the
8367 in order to affect any further processing in the running shell:
8369 .Bd -literal -offset indent
8370 $ EDITOR="vim -u ${HOME}/.vimrc"
8372 $ COLUMNS=80 \*(uA -R
8375 .Bl -tag -width ".It Ev _AILR_"
8378 The user's preferred width in column positions for the terminal screen
8380 Queried and used once on program startup, actively managed for child
8381 processes and the MLE (see
8382 .Sx "On terminal control and line editor" )
8383 in interactive mode thereafter.
8387 The name of the file to use for saving aborted messages if
8389 is set; this defaults to
8397 Pathname of the text editor to use in the
8401 .Sx "TILDE ESCAPES" .
8402 A default editor is used if this value is not defined.
8406 The user's home directory.
8407 This variable is only used when it resides in the process environment.
8414 .It Ev LANG , LC_ALL , LC_COLLATE , LC_CTYPE , LC_MESSAGES
8418 .Sx "Character sets" .
8419 (Only recognized by the system in the process environment.)
8423 The user's preferred number of lines on a page or the vertical screen
8424 or window size in lines.
8425 Queried and used once on program startup, actively managed for child
8426 processes in interactive mode thereafter.
8430 Pathname of the directory lister to use in the
8432 command when operating on local mailboxes.
8435 (path search through
8440 Upon startup \*(UA will actively ensure that this variable refers to the
8441 name of the user who runs \*(UA, in order to be able to pass a verified
8442 name to any newly created child process.
8446 Is used as the user's primary system mailbox, if set.
8447 Otherwise, a system-dependent default is used.
8448 Supports the special syntax conventions that are documented for the
8454 \*(OP Overrides the default path search for
8455 .Sx "The Mailcap files" ,
8456 which is defined in the standard RFC 1524 as
8457 .Ql ~/.mailcap:\:/etc/mailcap:\:/usr/etc/mailcap:\:/usr/local/etc/mailcap .
8458 .\" TODO we should have a mailcaps-default virtual RDONLY option!
8459 (\*(UA makes it a configuration option, however.)
8460 Note this is not a search path, but a path search.
8464 Is used as a startup file instead of
8467 When \*(UA scripts are invoked on behalf of other users,
8468 either this variable should be set to
8472 command line option should be used in order to avoid side-effects from
8473 reading their configuration files.
8474 This variable is only used when it resides in the process environment.
8478 The name of the user's mbox file.
8479 A logical subset of the special conventions that are documented for the
8484 The fallback default is
8489 Traditionally this secondary mailbox is used as the file to save
8490 messages from the primary system mailbox that have been read.
8492 .Sx "Message states" .
8495 .It Ev NAIL_NO_SYSTEM_RC
8496 If this variable is set then reading of
8498 at startup is inhibited, i.e., the same effect is achieved as if \*(UA
8499 had been started up with the option
8501 This variable is only used when it resides in the process environment.
8505 \*(IN\*(OP This variable overrides the default location of the user's
8511 Pathname of the program to use for backing the command
8515 variable enforces usage of a pager for output.
8516 The default paginator is
8518 (path search through
8521 \*(UA inspects the contents of this variable: if its contains the string
8523 then a non-existing environment variable
8530 dependent on whether terminal control support is available and whether
8531 that supports full (alternative) screen mode or not (also see
8532 .Sx "On terminal control and line editor" ) .
8536 will optionally be set to
8543 A list of directories that is searched by the shell when looking for
8544 commands (as such only recognized in the process environment).
8548 The shell to use for the commands
8554 and when starting subprocesses.
8555 A default shell is used if this option is not defined.
8559 \*(OP The terminal type for which output is to be prepared.
8560 For extended colour and font control please refer to
8561 .Sx "Coloured display" ,
8562 and for terminal management in general to
8563 .Sx "On terminal control and line editor" .
8567 Used as directory for temporary files instead of
8570 This variable is only used when it resides in the process environment.
8576 (see there), but this variable is not standardized, should therefore not
8577 be used, and is only corrected if already set.
8581 Pathname of the text editor to use in the
8585 .Sx "TILDE ESCAPES" .
8593 .Bl -tag -width ".It Pa _etc/mime.type_"
8595 File giving initial commands.
8598 System wide initialization file.
8602 \*(OP Personal MIME type handler definition file, see
8603 .Sx "The Mailcap files" .
8604 (RFC 1524 location, the actual path is a configuration option.)
8608 \*(OP System wide MIME type handler definition file, see
8609 .Sx "The Mailcap files" .
8610 (RFC 1524 location, the actual path is a configuration option.)
8613 .It Pa ~/.mime.types
8614 Personal MIME types, see
8615 .Sx "The mime.types files" .
8618 .It Pa /etc/mime.types
8619 System wide MIME types, see
8620 .Sx "The mime.types files" .
8624 \*(IN\*(OP The default location of the users
8626 file \(en the section
8627 .Sx "The .netrc file"
8628 documents the file format.
8631 .\" .Ss "The mime.types files" {{{
8632 .Ss "The mime.types files"
8634 When sending messages \*(UA tries to determine the content type of all
8636 When displaying message content or attachments \*(UA uses the content
8637 type to decide whether it can directly display data or whether it needs
8638 to deal with content handlers.
8639 It learns about MIME types and how to treat them by reading
8641 files, the loading of which can be controlled by setting the variable
8642 .Va mimetypes-load-control .
8645 can also be used to deal with MIME types.)
8647 files have the following syntax:
8650 .Dl type/subtype extension [extension ...]
8655 are strings describing the file contents, and one or multiple
8657 s, separated by whitespace, name the part of a filename starting after
8658 the last dot (of interest).
8659 Comments may be introduced anywhere on a line with a number sign
8661 causing the remaining line to be discarded.
8663 \*(UA also supports an extended, non-portable syntax in specially
8664 crafted files, which can be loaded via the alternative value syntax of
8665 .Va mimetypes-load-control
8666 and prepends an optional
8670 .Dl [type-marker ]type/subtype extension [extension ...]
8673 The following type markers are supported:
8676 .Bl -tag -compact -offset indent -width ".It Ar _n_u"
8678 Treat message parts with this content as plain text.
8683 Treat message parts with this content as HTML tagsoup.
8684 If the \*(OPal HTML-tagsoup-to-text converter is not available treat
8685 the content as plain text instead.
8689 but instead of falling back to plain text require an explicit content
8690 handler to be defined.
8695 for sending messages:
8697 .Va mime-allow-text-controls ,
8698 .Va mimetypes-load-control .
8699 For reading etc. messages:
8700 .Sx "HTML mail and MIME attachments" ,
8701 .Sx "The Mailcap files" ,
8703 .Va mime-counter-evidence ,
8704 .Va mimetypes-load-control ,
8705 .Va pipe-TYPE/SUBTYPE ,
8706 .Va pipe-EXTENSION .
8709 .\" .Ss "The Mailcap files" {{{
8710 .Ss "The Mailcap files"
8713 .Dq User Agent Configuration Mechanism
8714 which \*(UA \*(OPally supports.
8715 It defines a file format to be used to inform mail user agent programs
8716 about the locally-installed facilities for handling various data
8717 formats, i.e., about commands and how they can be used to display, edit
8718 etc. MIME part contents, as well as a default path search that includes
8719 multiple possible locations of
8723 environment variable that can be used to overwrite that (repeating here
8724 that it is not a search path, but instead a path search specification).
8725 Any existing files will be loaded in sequence, appending any content to
8726 the list of MIME type handler directives.
8730 files consist of a set of newline separated entries.
8731 Comment lines start with a number sign
8733 (in the first column!) and are ignored.
8734 Empty lines are also ignored.
8735 All other lines form individual entries that must adhere to the syntax
8737 To extend a single entry (not comment) its line can be continued on
8738 follow lines if newline characters are
8740 by preceding them with the backslash character
8742 The standard doesn't specify how leading whitespace of follow lines is
8743 to be treated, therefore \*(UA retains it.
8747 entries consist of a number of semicolon
8749 separated fields, and the backslash
8751 character can be used to escape any following character including
8752 semicolon and itself.
8753 The first two fields are mandatory and must occur in the specified
8754 order, the remaining fields are optional and may appear in any order.
8755 Leading and trailing whitespace of content is ignored (removed).
8758 The first field defines the MIME
8760 the entry is about to handle (case-insensitively, and no backslash
8761 escaping is possible in this field).
8762 If the subtype is specified as an asterisk
8764 the entry is meant to match all subtypes of the named type, e.g.,
8766 would match any audio type.
8767 The second field defines the shell command which shall be used to
8769 MIME parts of the given type; it is implicitly called the
8776 shell commands message (MIME part) data is passed via standard input
8777 unless the given shell command includes one or more instances of the
8780 in which case these instances will be replaced with a temporary filename
8781 and the data will have been stored in the file that is being pointed to.
8784 shell commands data is assumed to be generated on standard output unless
8785 the given command includes (one ore multiple)
8787 In any case any given
8789 format is replaced with a(n already) properly quoted filename.
8790 Note that when a command makes use of a temporary file via
8792 then \*(UA will remove it again, as if the
8793 .Cd x-mailx-tmpfile ,
8794 .Cd x-mailx-tmpfile-fill
8796 .Cd x-mailx-tmpfile-unlink
8797 flags had been set; see below for more.
8800 The optional fields either define a shell command or an attribute (flag)
8801 value, the latter being a single word and the former being a keyword
8802 naming the field followed by an equals sign
8804 succeeded by a shell command, and as usual for any
8806 content any whitespace surrounding the equals sign will be removed, too.
8807 Optional fields include the following:
8810 .Bl -tag -width textualnewlines
8812 A program that can be used to compose a new body or body part in the
8819 field, but is to be used when the composing program needs to specify the
8821 header field to be applied to the composed data.
8825 A program that can be used to edit a body or body part in the given
8830 A program that can be used to print a message or body part in the given
8835 Specifies a program to be run to test some condition, e.g., the machine
8836 architecture, or the window system in use, to determine whether or not
8837 this mailcap entry applies.
8838 If the test fails, a subsequent mailcap entry should be sought; also see
8839 .Cd x-mailx-test-once .
8841 .It Cd needsterminal
8842 This flag field indicates that the given shell command must be run on
8843 an interactive terminal.
8844 \*(UA will temporarily release the terminal to the given command in
8845 interactive mode, in non-interactive mode this entry will be entirely
8846 ignored; this flag implies
8847 .Cd x-mailx-noquote .
8849 .It Cd copiousoutput
8850 A flag field which indicates that the output of the
8852 command will be an extended stream of textual output that can be
8853 (re)integrated into \*(UA's normal visual display.
8854 It is mutually exclusive with
8857 .Cd x-mailx-always .
8859 .It Cd textualnewlines
8860 A flag field which indicates that this type of data is line-oriented and
8863 all newlines should be converted to canonical form (CRLF) before
8864 encoding, and will be in that form after decoding.
8868 This field gives a file name format, in which
8870 will be replaced by a random string, the joined combination of which
8871 will be used as the filename denoted by
8872 .Ev NAIL_FILENAME_TEMPORARY .
8873 One could specify that a GIF file being passed to an image viewer should
8874 have a name ending in
8877 .Ql nametemplate=%s.gif .
8878 Note that \*(UA ignores the name template unless that solely specifies
8879 a filename suffix that consists of (ASCII) alphabetic and numeric
8880 characters, the underscore and dot only.
8883 Names a file, in X11 bitmap (xbm) format, which points to an appropriate
8884 icon to be used to visually denote the presence of this kind of data.
8885 This field is not used by \*(UA.
8888 A textual description that describes this type of data.
8890 .It Cd x-mailx-always
8891 Extension flag field that denotes that the given
8893 command shall be executed even if multiple messages will be displayed
8895 Normally messages which require external viewers that produce output
8896 which doesn't integrate into \*(UA's visual display (i.e., don't have
8898 set) have to be addressed directly and individually.
8899 (To avoid cases where, e.g., a thousand PDF viewer instances are spawned
8902 .It Cd x-mailx-even-if-not-interactive
8903 An extension flag test field \(em by default handlers without
8905 are entirely ignored in non-interactive mode, but if this flag is set
8906 then their use will be considered.
8907 It is an error if this flag is set for commands that use the flag
8910 .It Cd x-mailx-noquote
8911 An extension flag field that indicates that even a
8914 command shall not be used to generate message quotes
8915 (as it would be by default).
8917 .It Cd x-mailx-async
8918 Extension flag field that denotes that the given
8920 command shall be executed asynchronously, without blocking \*(UA.
8921 Cannot be used in conjunction with
8924 .It Cd x-mailx-test-once
8925 Extension flag which denotes whether the given
8927 command shall be evaluated once only and the (boolean) result be cached.
8928 This is handy if some global unchanging condition is to be queried, like
8929 .Dq running under the X Window System .
8931 .It Cd x-mailx-tmpfile
8932 Extension flag field that requests creation of a zero-sized temporary
8933 file, the name of which is to be placed in the environment variable
8934 .Ev NAIL_FILENAME_TEMPORARY .
8935 It is an error to use this flag with commands that include a
8939 .It Cd x-mailx-tmpfile-fill
8940 Normally the MIME part content is passed to the handler via standard
8941 input; if this flag is set then the data will instead be written into
8943 .Cd x-mailx-tmpfile .
8944 In order to cause deletion of the temporary file you will have to set
8945 .Cd x-mailx-tmpfile-unlink
8947 It is an error to use this flag with commands that include a
8951 .It Cd x-mailx-tmpfile-unlink
8952 Extension flag field that requests that the temporary file shall be
8953 deleted automatically when the command loop is entered again at latest.
8954 (Don't use this for asynchronous handlers.)
8955 It is an error to use this flag with commands that include a
8957 format, or without also setting
8960 .Cd x-mailx-tmpfile-fill .
8962 .It Cd x-mailx-tmpfile-keep
8965 implies the three tmpfile related flags above, but if you want, e.g.,
8967 and deal with the temporary file yourself, you can add in this flag to
8969 .Cd x-mailx-tmpfile-unlink .
8974 The standard includes the possibility to define any number of additional
8975 entry fields, prefixed by
8977 Flag fields apply to the entire
8979 entry \(em in some unusual cases, this may not be desirable, but
8980 differentiation can be accomplished via separate entries, taking
8981 advantage of the fact that subsequent entries are searched if an earlier
8982 one does not provide enough information.
8985 command needs to specify the
8989 command shall not, the following will help out the latter (with enabled
8993 level \*(UA will show information about handler evaluation):
8995 .Bd -literal -offset indent
8996 application/postscript; ps-to-terminal %s; needsterminal
8997 application/postscript; ps-to-terminal %s; compose=idraw %s
9001 In fields any occurrence of the format string
9003 will be replaced by the
9006 Named parameters from the
9008 field may be placed in the command execution line using
9010 followed by the parameter name and a closing
9013 The entire parameter should appear as a single command line argument,
9014 regardless of embedded spaces; thus:
9016 .Bd -literal -offset indent
9018 Content-type: multipart/mixed; boundary=42
9021 multipart/*; /usr/local/bin/showmulti \e
9022 %t %{boundary} ; composetyped = /usr/local/bin/makemulti
9024 # Executed shell command
9025 /usr/local/bin/showmulti multipart/mixed 42
9029 .\" TODO v15: Mailcap: %n,%F
9030 Note that \*(UA doesn't support handlers for multipart MIME parts as
9031 shown in this example (as of today).
9032 \*(UA doesn't support the additional formats
9036 An example file, also showing how to properly deal with the expansion of
9038 which includes any quotes that are necessary to make it a valid shell
9039 argument by itself and thus will cause undesired behaviour when placed
9040 in additional user-provided quotes:
9042 .Bd -literal -offset indent
9044 text/richtext; richtext %s; copiousoutput
9046 text/x-perl; perl -cWT %s
9050 trap "rm -f ${infile}" EXIT\e; \e
9051 trap "exit 75" INT QUIT TERM\e; \e
9053 x-mailx-async; x-mailx-tmpfile-keep
9055 application/*; echo "This is \e"%t\e" but \e
9056 is 50 \e% Greek to me" \e; < %s head -c 1024 | cat -vET; \e
9057 copiousoutput; x-mailx-noquote
9062 .Sx "HTML mail and MIME attachments" ,
9063 .Sx "The mime.types files" ,
9066 .Va mime-counter-evidence ,
9067 .Va pipe-TYPE/SUBTYPE ,
9068 .Va pipe-EXTENSION .
9071 .\" .Ss "The .netrc file" {{{
9072 .Ss "The .netrc file"
9076 file contains user credentials for machine accounts.
9077 The default location in the user's
9079 directory may be overridden by the
9081 environment variable.
9082 The file consists of space, tabulator or newline separated tokens.
9083 \*(UA implements a parser that supports a superset of the original BSD
9084 syntax, but users should nonetheless be aware of portability glitches
9085 of that file format, shall their
9087 be usable across multiple programs and platforms:
9090 .Bl -bullet -compact
9092 BSD doesn't support single, but only double quotation marks, e.g.,
9093 .Ql password="pass with spaces" .
9095 BSD (only?) supports escaping of single characters via a backslash
9096 (e.g., a space can be escaped via
9098 in- as well as outside of a quoted string.
9100 BSD doesn't require the final quotation mark of the final user input token.
9102 The original BSD (Berknet) parser also supported a format which allowed
9103 tokens to be separated with commas \(en whereas at least Hewlett-Packard
9104 still seems to support this syntax, \*(UA does not!
9106 As a non-portable extension some widely-used programs support
9107 shell-style comments: if an input line starts, after any amount of
9108 whitespace, with a number sign
9110 then the rest of the line is ignored.
9112 Whereas other programs may require that the
9114 file is accessible by only the user if it contains a
9120 \*(UA will always require these strict permissions.
9124 Of the following list of supported tokens \*(UA only uses (and caches)
9129 At runtime the command
9131 can be used to control \*(UA's
9135 .Bl -tag -width password
9136 .It Cd machine Ar name
9137 The hostname of the entries' machine, lowercase-normalized by \*(UA
9139 Any further file content, until either end-of-file or the occurrence
9144 first-class token is bound (only related) to the machine
9147 As an extension that shouldn't be the cause of any worries
9148 \*(UA supports a single wildcard prefix for
9150 .Bd -literal -offset indent
9151 machine *.example.com login USER password PASS
9152 machine pop3.example.com login USER password PASS
9153 machine smtp.example.com login USER password PASS
9159 .Ql pop3.example.com ,
9163 .Ql local.smtp.example.com .
9164 Note that in the example neither
9165 .Ql pop3.example.com
9167 .Ql smtp.example.com
9168 will be matched by the wildcard, since the exact matches take
9169 precedence (it is however faster to specify it the other way around).
9174 except that it is a fallback entry that is used shall none of the
9175 specified machines match; only one default token may be specified,
9176 and it must be the last first-class token.
9178 .It Cd login Ar name
9179 The user name on the remote machine.
9181 .It Cd password Ar string
9182 The user's password on the remote machine.
9184 .It Cd account Ar string
9185 Supply an additional account password.
9186 This is merely for FTP purposes.
9188 .It Cd macdef Ar name
9190 A macro is defined with the specified
9192 it is formed from all lines beginning with the next line and continuing
9193 until a blank line is (consecutive newline characters are) encountered.
9196 entries cannot be utilized by multiple machines, too, but must be
9197 defined following the
9199 they are intended to be used with.)
9202 exists, it is automatically run as the last step of the login process.
9203 This is merely for FTP purposes.
9210 .\" .Sh EXAMPLES {{{
9213 .\" .Ss "An example configuration" {{{
9214 .Ss "An example configuration"
9216 .Bd -literal -offset indent
9217 # This example assumes v15.0 compatibility mode
9220 # Where are the up-to-date SSL certificates?
9221 #set ssl-ca-dir=/etc/ssl/certs
9222 set ssl-ca-file=/etc/ssl/certs/ca-certificates.crt
9224 # (Since we manage up-to-date ones explicitly, don't use any,
9225 # possibly outdated, default certificates shipped with OpenSSL
9226 set ssl-no-default-ca
9228 # Don't use protocols older than TLS v1.2.
9229 # Change this only when the remote server doesn't support it:
9230 # maybe use ssl-protocol-HOST (or -USER@HOST) syntax to define
9231 # such explicit exceptions, then
9232 set ssl-protocol='-ALL,+TLSv1.2'
9234 # Explicitly define the list of ciphers, which may improve security,
9235 # especially with protocols older than TLS v1.2. See ciphers(1).
9236 # Hint: it is important to include "@STRENGTH": only with it the
9237 # final list will be sorted by algorithm strength.
9238 # This is an example: in reality it is possibly best to only use
9239 # ssl-cipher-list-HOST (or -USER@HOST), as necessary, again..
9240 set ssl-cipher-list='ALL:!aNULL:!MEDIUM:!LOW:\e
9241 !MD5:!RC4:!EXPORT:@STRENGTH'
9243 # Request strict transport security checks!
9244 set ssl-verify=strict
9246 # Essential setting: select allowed character sets
9247 set sendcharsets=utf-8,iso-8859-1
9249 # A very kind option: when replying to a message, first try to
9250 # use the same encoding that the original poster used herself!
9251 set reply-in-same-charset
9253 # When replying to or forwarding a message the comment and name
9254 # parts of email addresses are removed unless this variable is set
9257 # When sending messages, wait until the Mail-Transfer-Agent finishs.
9258 # Only like this you'll be able to see errors reported through the
9259 # exit status of the MTA (including the builtin SMTP one)!
9262 # Only use builtin MIME types, no mime.types(5) files
9263 set mimetypes-load-control
9265 # Default directory where we act in (relative to $HOME)
9267 # A leading "+" (often) means: under *folder*
9268 # *record* is used to save copies of sent messages
9269 set MBOX=+mbox.mbox record=+sent.mbox DEAD=+dead.mbox
9271 # Make "file mymbox" and "file myrec" go to..
9272 shortcut mymbox %:+mbox.mbox myrec +sent.mbox
9274 # Not really optional, e.g., for S/MIME
9275 set from='Your Name <address@exam.ple>'
9277 # It may be necessary to set hostname and/or smtp-hostname
9278 # if the "SERVER" of smtp and "domain" of from don't match.
9279 # The `urlencode' command can be used to encode USER and PASS
9280 set smtp=(smtp[s]/submission)://[USER[:PASS]@]SERVER[:PORT] \e
9281 smtp-auth=login/plain... \e
9284 # Never refuse to start into interactive mode, and more
9286 colour-pager crt= \e
9287 followup-to followup-to-honour=ask-yes \e
9288 history-file=+.\*(uAhist history-size=-1 history-gabby \e
9289 mime-counter-evidence=0xE \e
9290 prompt='?\e?[\e$ \e@]\e& ' \e
9291 reply-to-honour=ask-yes
9293 # When `t'yping messages, show only these headers
9294 # (use `T'ype for all headers and `S'how for raw message)
9295 retain date from to cc subject
9297 # Some mailing lists
9298 mlist '@xyz-editor\e.xyz'$ '@xyzf\e.xyz$'
9299 mlsubscribe '^xfans@xfans\e.xyz$'
9301 # A real life example of a very huge free mail provider
9303 set folder=~/spool/XooglX MAIL=+syste.mbox sent=+sent
9304 set from='Your Name <address@examp.ple>'
9305 # (The plain smtp:// proto is optional)
9306 set smtp=USER:PASS@smtp.gmXil.com smtp-use-starttls
9309 # Here is a pretty large one which does not allow sending mails
9310 # if there is a domain name mismatch on the SMTP protocol level,
9311 # which would bite us if the value of from does not match, e.g.,
9312 # for people who have a sXXXXeforge project and want to speak
9313 # with the mailing list under their project account (in from),
9314 # still sending the message through their normal mail provider
9316 set folder=~/spool/XandeX MAIL=+syste.mbox sent=+sent
9317 set from='Your Name <address@exam.ple>'
9318 set smtp=smtps://USER:PASS@smtp.yaXXex.ru:465 \e
9319 hostname=yaXXex.com smtp-hostname=
9322 # Create some new commands so that, e.g., `ls /tmp' will..
9333 ghost llS !ls -aFlrS
9336 # We don't support gpg(1) directly yet. But simple --clearsign'd
9337 # message parts can be dealt with as follows:
9339 wysh set pipe-text/plain=$'@*#++=@\e
9340 < "${NAIL_FILENAME_TEMPORARY}" awk \e
9341 -v TMPFILE="${NAIL_FILENAME_TEMPORARY}" \e'\e
9343 /^-----BEGIN PGP SIGNED MESSAGE-----/,/^$/{\e
9346 print "--- GPG --verify ---";\e
9347 system("gpg --verify " TMPFILE " 2>&1");\e
9348 print "--- GPG --verify ---";\e
9352 /^-----BEGIN PGP SIGNATURE-----/,\e
9353 /^-----END PGP SIGNATURE-----/{\e
9363 !printf 'Key IDs to gpg --recv-keys: ';\e
9365 gpg --recv-keys ${keyids};
9371 When storing passwords in
9373 appropriate permissions should be set on this file with
9374 .Ql $ chmod 0600 \*(ur .
9377 is available user credentials can be stored in the central
9379 file instead; e.g., here is a different version of the example account
9380 that sets up SMTP and POP3:
9382 .Bd -literal -offset indent
9384 set folder=~/spool/XandeX MAIL=+syste.mbox sent=+sent
9385 set from='Your Name <address@exam.ple>'
9387 #set agent-shell-lookup='gpg -d .pass.gpg'
9389 set smtp=smtps://smtp.yXXXXx.ru:465 \e
9390 smtp-hostname= hostname=yXXXXx.com
9391 set pop3-keepalive=240 pop3-no-apop-pop.yXXXXx.ru
9392 ghost xp fi pop3s://pop.yXXXXx.ru
9401 .Bd -literal -offset indent
9402 machine *.yXXXXx.ru login USER password PASS
9407 .Va agent-shell-lookup
9408 is available things could be diversified further by using encrypted
9409 password storage: for this, don't specify
9413 file and instead uncomment the line that defines agent lookup in the
9416 above, then create the encrypted password storage file
9419 .Bd -literal -offset indent
9422 $ eval `gpg-agent --daemon \e
9423 --pinentry-program=/usr/bin/pinentry-curses \e
9424 --max-cache-ttl 99999 --default-cache-ttl 99999`
9428 This configuration should now work just fine (use the
9430 command line option for a(n almost) dry-run):
9433 .Dl $ echo text | \*(uA -vv -AXandeX -s Subject user@exam.ple
9436 .\" .Ss "Signed and encrypted messages with S/MIME" {{{
9437 .Ss "Signed and encrypted messages with S/MIME"
9439 \*(OP S/MIME provides two central mechanisms:
9440 message signing and message encryption.
9441 A signed message contains some data in addition to the regular text.
9442 The data can be used to verify that the message was sent using a valid
9443 certificate, that the sender's address in the message header matches
9444 that in the certificate, and that the message text has not been altered.
9445 Signing a message does not change its regular text;
9446 it can be read regardless of whether the recipient's software is able to
9450 It is thus usually possible to sign all outgoing messages if so desired.
9451 Encryption, in contrast, makes the message text invisible for all people
9452 except those who have access to the secret decryption key.
9453 To encrypt a message, the specific recipient's public encryption key
9455 It is therefore not possible to send encrypted mail to people unless their
9456 key has been retrieved from either previous communication or public key
9458 A message should always be signed before it is encrypted.
9459 Otherwise, it is still possible that the encrypted message text is
9463 A central concept to S/MIME is that of the certification authority (CA).
9464 A CA is a trusted institution that issues certificates.
9465 For each of these certificates it can be verified that it really
9466 originates from the CA, provided that the CA's own certificate is
9468 A set of CA certificates is usually delivered with OpenSSL and installed
9470 If you trust the source of your OpenSSL software installation,
9471 this offers reasonable security for S/MIME on the Internet.
9473 .Va ssl-no-default-ca
9477 .Va smime-ca-dir . )
9478 In general, a certificate cannot be more secure than the method its CA
9479 certificate has been retrieved with, though.
9480 Thus if you download a CA certificate from the Internet,
9481 you can only trust the messages you verify using that certificate as
9482 much as you trust the download process.
9485 The first thing you need for participating in S/MIME message exchange is
9486 your personal certificate, including a private key.
9487 The certificate contains public information, in particular your name and
9488 your email address(es), and the public key that is used by others to
9489 encrypt messages for you,
9490 and to verify signed messages they supposedly received from you.
9491 The certificate is included in each signed message you send.
9492 The private key must be kept secret.
9493 It is used to decrypt messages that were previously encrypted with your
9494 public key, and to sign messages.
9497 For personal use it is recommended that you get a S/MIME certificate
9498 from one of the major CAs on the Internet using your WWW browser.
9499 Many CAs offer such certificates for free.
9501 .Lk https://www.CAcert.org
9502 which issues client and server certificates to members of their
9503 community for free; their root certificate
9504 .Pf ( Lk https://\:www.cacert.org/\:certs/\:root.crt )
9505 is often not in the default set of trusted CA root certificates, though,
9506 which means you will have to download their root certificate separately
9507 and ensure it is part of our S/MIME certificate validation chain by
9510 or as a vivid member of the
9512 But let's take a step-by-step tour on how to setup S/MIME with
9513 a certificate from CAcert.org despite this situation!
9516 First of all you will have to become a member of the CAcert.org
9517 community, simply by registrating yourself via the web interface.
9518 Once you are, create and verify all email addresses you want to be able
9519 to create signed and encrypted messages for/with using the corresponding
9520 entries of the web interface.
9521 Now ready to create S/MIME certificates, so let's create a new
9522 .Dq client certificate ,
9523 ensure to include all email addresses that should be covered by the
9524 certificate in the following web form, and also to use your name as the
9528 Create a private key and a certificate request on your local computer
9529 (please see the manual pages of the used commands for more in-depth
9530 knowledge on what the used arguments etc. do):
9533 .Dl openssl req -nodes -newkey rsa:4096 -keyout key.pem -out creq.pem
9536 Afterwards copy-and-paste the content of
9538 into the certificate-request (CSR) field of the web form on the
9539 CAcert.org website (you may need to unfold some
9540 .Dq advanced options
9541 to see the corresponding text field).
9542 This last step will ensure that your private key (which never left your
9543 box) and the certificate belong together (through the public key that
9544 will find its way into the certificate via the certificate-request).
9545 You are now ready and can create your CAcert certified certificate.
9546 Download and store or copy-and-paste it as
9551 In order to use your new S/MIME setup you will have to create
9552 a combined private key/public key (certificate) file:
9555 .Dl cat key.pem pub.crt > ME@HERE.com.paired
9558 This is the file \*(UA will work with.
9559 If you have created your private key with a passphrase then \*(UA will
9560 ask you for it whenever a message is signed or decrypted.
9561 Set the following variables to henceforth use S/MIME (setting
9563 is of interest for verification only):
9565 .Bd -literal -offset indent
9566 set smime-ca-file=ALL-TRUSTED-ROOT-CERTS-HERE \e
9567 smime-sign-cert=ME@HERE.com.paired \e
9568 smime-sign-message-digest=SHA256 \e
9573 From each signed message you send, the recipient can fetch your
9574 certificate and use it to send encrypted mail back to you.
9575 Accordingly if somebody sends you a signed message, you can do the same,
9578 command to check the validity of the certificate.
9581 Variables of interest for S/MIME signing:
9585 .Va smime-crl-file ,
9586 .Va smime-no-default-ca ,
9588 .Va smime-sign-cert ,
9589 .Va smime-sign-include-certs
9591 .Va smime-sign-message-digest .
9594 After it has been verified save the certificate via
9596 and tell \*(UA that it should use it for encryption for further
9597 communication with that somebody:
9599 .Bd -literal -offset indent
9601 set smime-encrypt-USER@HOST=FILENAME \e
9602 smime-cipher-USER@HOST=AES256
9606 Additional variables of interest for S/MIME en- and decryption:
9609 .Va smime-encrypt-USER@HOST .
9612 You should carefully consider if you prefer to store encrypted messages
9614 If you do, anybody who has access to your mail folders can read them,
9615 but if you do not, you might be unable to read them yourself later if
9616 you happen to lose your private key.
9619 command saves messages in decrypted form, while the
9623 commands leave them encrypted.
9626 Note that neither S/MIME signing nor encryption applies to message
9627 subjects or other header fields yet.
9628 Thus they may not contain sensitive information for encrypted messages,
9629 and cannot be trusted even if the message content has been verified.
9630 When sending signed messages,
9631 it is recommended to repeat any important header information in the
9635 .\" .Ss "Using CRLs with S/MIME or SSL/TLS" {{{
9636 .Ss "Using CRLs with S/MIME or SSL/TLS"
9638 \*(OP Certification authorities (CAs) issue certificate revocation
9639 lists (CRLs) on a regular basis.
9640 These lists contain the serial numbers of certificates that have been
9641 declared invalid after they have been issued.
9642 Such usually happens because the private key for the certificate has
9644 because the owner of the certificate has left the organization that is
9645 mentioned in the certificate, etc.
9646 To seriously use S/MIME or SSL/TLS verification,
9647 an up-to-date CRL is required for each trusted CA.
9648 There is otherwise no method to distinguish between valid and
9649 invalidated certificates.
9650 \*(UA currently offers no mechanism to fetch CRLs, nor to access them on
9651 the Internet, so you have to retrieve them by some external mechanism.
9654 \*(UA accepts CRLs in PEM format only;
9655 CRLs in DER format must be converted, like, e.\|g.:
9658 .Dl $ openssl crl \-inform DER \-in crl.der \-out crl.pem
9661 To tell \*(UA about the CRLs, a directory that contains all CRL files
9662 (and no other files) must be created.
9667 variables, respectively, must then be set to point to that directory.
9668 After that, \*(UA requires a CRL to be present for each CA that is used
9669 to verify a certificate.
9672 .\" .Ss "Handling spam" {{{
9675 \*(OP \*(UA can make use of several spam interfaces for the purpose of
9676 identification of, and, in general, dealing with spam messages.
9677 A precondition of most commands in order to function is that the
9679 variable is set to one of the supported interfaces.
9680 Once messages have been identified as spam their (volatile)
9682 state can be prompted: the
9686 message specifications will address respective messages and their
9688 entries will be used when displaying the
9690 in the header display.
9695 rates the given messages and sets their
9698 If the spam interface offers spam scores those can also be displayed in
9699 the header display by including the
9709 will interact with the Bayesian filter of the chosen interface and learn
9710 the given messages as
9714 respectively; the last command can be used to cause
9716 of messages; it adheres to their current
9718 state and thus reverts previous teachings.
9723 will simply set and clear, respectively, the mentioned volatile
9725 message flag, without any interface interaction.
9732 .Va spam-interface Ns s
9736 require a running instance of the
9738 server in order to function, started with the option
9740 shall Bayesian filter learning be possible.
9742 only works via a local path-based
9744 socket, but otherwise the following will be equivalently fine:
9746 .Bd -literal -offset indent
9747 $ spamd -i localhost:2142 -i /tmp/.spamsock -d [-L] [-l]
9748 $ spamd --listen=localhost:2142 --listen=/tmp/.spamsock \e
9749 --daemonize [--local] [--allow-tell]
9753 Thereafter \*(UA can make use of these interfaces:
9755 .Bd -literal -offset indent
9756 $ \*(uA -Sspam-interface=spamd -Sspam-maxsize=500000 \e
9757 -Sspamd-socket=/tmp/.spamsock -Sspamd-user=
9759 $ \*(uA -Sspam-interface=spamc -Sspam-maxsize=500000 \e
9760 -Sspamc-command=/usr/local/bin/spamc \e
9761 -Sspamc-arguments="-U /tmp/.spamsock" -Sspamc-user=
9763 $ \*(uA -Sspam-interface=spamc -Sspam-maxsize=500000 \e
9764 -Sspamc-command=/usr/local/bin/spamc \e
9765 -Sspamc-arguments="-d localhost -p 2142" -Sspamc-user=
9769 Using the generic filter approach allows usage of programs like
9773 Here is an example for the former, requiring it to be accessible via
9776 .Bd -literal -offset indent
9777 $ \*(uA -Sspam-interface=filter -Sspam-maxsize=500000 \e
9778 -Sspamfilter-ham="bogofilter -n" \e
9779 -Sspamfilter-noham="bogofilter -N" \e
9780 -Sspamfilter-nospam="bogofilter -S" \e
9781 -Sspamfilter-rate="bogofilter -TTu 2>/dev/null" \e
9782 -Sspamfilter-spam="bogofilter -s" \e
9783 -Sspamfilter-rate-scanscore="1;^(.+)$"
9787 Because messages must exist on local storage in order to be scored (or
9788 used for Bayesian filter training), it is possibly a good idea to
9789 perform the local spam check last:
9791 .Bd -literal -offset indent
9792 define spamdelhook {
9794 spamset (header x-dcc-brand-metrics "bulk")
9795 # Server-side spamassassin(1)
9796 spamset (header x-spam-flag "YES")
9797 del :s # TODO we HAVE to be able to do `spamrate :u ! :sS'
9803 set folder-hook-FOLDER=spamdelhook
9807 See also the documentation for the variables
9808 .Va spam-interface , spam-maxsize ,
9809 .Va spamc-command , spamc-arguments , spamc-user ,
9810 .Va spamd-socket , spamd-user ,
9811 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
9814 .Va spamfilter-rate-scanscore .
9822 .\" .Ss "\*(UA shortly hangs on startup" {{{
9823 .Ss "\*(UA shortly hangs on startup"
9825 This can have two reasons, one is the necessity to wait for a file lock
9826 and can't be helped, the other being that \*(UA calls the function
9828 in order to query the nodename of the box (sometimes the real one is
9829 needed instead of the one represented by the internal variable
9831 You may have varying success by ensuring that the real hostname and
9835 or, more generally, that the name service is properly setup \(en
9838 return what you'd expect?
9839 Does this local hostname has a domain suffix?
9840 RFC 6762 standardized the link-local top-level domain
9844 .\" .Ss "I can't login to Google mail aka GMail" {{{
9845 .Ss "I can't login to Google mail aka GMail"
9847 Since 2014 some free service providers classify programs as
9849 unless they use a special authentification method (OAuth 2.0) which
9850 wasn't standardized for non-HTTP protocol authentication token query
9851 until August 2015 (RFC 7628).
9854 Different to Kerberos / GSSAPI, which is developed since the mid of the
9855 1980s, where a user can easily create a local authentication ticket for
9856 her- and himself with the locally installed
9858 program, that protocol has no such local part but instead requires
9859 a world-wide-web query to create or fetch a token; since there is no
9860 local cache this query has to be performed whenever \*(UA is invoked
9861 from the command line (in interactive sessions situation may differ).
9864 \*(UA doesn't support OAuth.
9865 Because of this it is necessary to declare \*(UA a
9867 (on the providers account web page) in order to read and send mail.
9868 However, it also seems possible to take the following steps instead:
9873 give the provider the number of a mobile phone,
9876 .Dq 2-Step Verification ,
9878 create an application specific password (16 characters), and
9880 use that special password instead of your real Google account password in
9881 \*(UA (for more on that see the section
9882 .Sx "On URL syntax and credential lookup" ) .
9888 .\" .Sh "SEE ALSO" {{{
9906 .Xr spamassassin 1 ,
9932 M. Douglas McIlroy writes in his article
9933 .Dq A Research UNIX Reader: Annotated Excerpts \
9934 from the Programmer's Manual, 1971-1986
9937 command already appeared in First Edition
9941 .Bd -ragged -offset indent
9942 Electronic mail was there from the start.
9943 Never satisfied with its exact behavior, everybody touched it at one
9944 time or another: to assure the safety of simultaneous access, to improve
9945 privacy, to survive crashes, to exploit uucp, to screen out foreign
9946 freeloaders, or whatever.
9947 Not until v7 did the interface change (Thompson).
9948 Later, as mail became global in its reach, Dave Presotto took charge and
9949 brought order to communications with a grab-bag of external networks
9955 Mail was written in 1978 by Kurt Shoens and developed as part of the
9958 distribution until 1995.
9959 Mail has then seen further development in open source
9961 variants, noticeably by Christos Zoulas in
9963 Basing upon this Nail, later Heirloom Mailx, was developed by Gunnar
9964 Ritter in the years 2000 until 2008.
9965 Since 2012 S-nail is maintained by Steffen (Daode) Nurpmeso.
9966 This man page is derived from
9967 .Dq The Mail Reference Manual
9968 that was originally written by Kurt Shoens.
9975 .An "Christos Zoulas" ,
9976 .An "Gunnar Ritter" ,
9977 .An "Steffen Nurpmeso" Aq Mt s-nail-users@lists.sourceforge.net
9979 .Mt s-mailx@sdaoden.eu ) .
9985 The character set conversion uses and relies upon the
9988 Its functionality differs widely between the various system environments
9992 Limitations with POP3 mailboxes are:
9993 It is not possible to edit messages, they can only be copied and deleted.
9994 The line count for the header display is only appropriate if the entire
9995 message has been downloaded from the server.
9996 The status field of a message is maintained by the server between
9997 connections; some servers do not update it at all, and with a server
10000 command will not cause the message status to be reset.
10005 variable have no effect.
10006 It is not possible to rename or to remove POP3 mailboxes.
10013 is typed while a POP3 operation is in progress, \*(UA will wait
10014 until the operation can be safely aborted, and will then return to the
10015 command loop and print the prompt again.
10018 is typed while \*(UA is waiting for the operation to complete, the
10019 operation itself will be cancelled.
10020 In this case, data that has not been fetched yet will have to be fetched
10021 before the next command can be performed.
10022 If the cancelled operation was using an SSL/TLS encrypted channel,
10023 an error in the SSL transport will very likely result and render the
10024 connection unusable.
10027 As \*(UA is a mail user agent, it provides only basic SMTP services.
10028 If it fails to contact its upstream SMTP server, it will not make
10029 further attempts to transfer the message at a later time,
10030 and it does not leave other information about this condition than an
10031 error message on the terminal and an entry in
10033 This is usually not a problem if the SMTP server is located in the same
10034 local network as the computer on which \*(UA is run.
10035 However, care should be taken when using a remote server of an ISP;
10036 it might be better to set up a local SMTP server then which just acts as
10040 \*(UA immediately contacts the SMTP server (or
10042 It would not make much sense for \*(UA to defer outgoing mail since SMTP
10043 servers usually provide much more elaborated delay handling than \*(UA
10044 could perform as a client.
10052 from the repository.
10054 After deleting some message of a POP3 mailbox the header summary falsely
10055 claims that there are no messages to display, you need to perform
10056 a scroll or dot movement to restore proper state.
10058 In threaded display a power user may encounter crashes very
10059 occasionally (this is may and very).