1 .\"@ nail.1 - S-nail(1) reference manual.
3 .\" Copyright (c) 2000-2008 Gunnar Ritter, Freiburg i. Br., Germany.
4 .\" Copyright (c) 2012 - 2016 Steffen (Daode) Nurpmeso <steffen@sdaoden.eu>.
6 .\" Copyright (c) 1980, 1990, 1993
7 .\" The Regents of the University of California. All rights reserved.
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. Neither the name of the University nor the names of its contributors
18 .\" may be used to endorse or promote products derived from this software
19 .\" without specific prior written permission.
21 .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 .\" S-nail(1): v14.9.0-pre1 / 2016-09-15
36 .ds VV \\%v14.9.0-pre1
46 .\" If not ~/.mailrc, it breaks POSIX compatibility. And adjust main.c.
51 .ds OU [no v15-compat]
52 .ds ID [v15 behaviour may differ]
53 .ds NQ [Only new quoting rules]
64 .Nd send and receive Internet mail
70 .\" Keep in SYNC: ./nail.1:"SYNOPSIS, main()
78 .Op Fl a Ar attachment
81 .Op Fl M Ar type | Fl m Ar file | Fl q Ar file | Fl t
83 .Op Fl S Ar var Ns Op Ns = Ns Ar value
88 .Op Fl Fl \~ Ns Ar mta-option ...
97 .Op Fl S Ar var Ns Op Ns = Ns Ar value
100 .Op Fl Fl \~ Ns Ar mta-option ...
108 .Op Fl L Ar spec-list
109 .Op Fl r Ar from-addr
110 .Op Fl S Ar var Ns Op Ns = Ns Ar value
113 .Op Fl Fl \~ Ns Ar mta-option ...
118 .Mx -toc -tree html pdf ps xhtml
121 .\" .Sh DESCRIPTION {{{
124 .Bd -filled -compact -offset indent
125 .Sy Compatibility note:
126 S-nail (\*(UA) will wrap up into \%S-mailx in v15.0 (circa 2018).
127 Backward incompatibility has to be expected \(en
131 -style argument quoting rules, for example.
132 New and old behaviour is flagged \*(IN and \*(OU, and setting
135 .Sx "INTERNAL VARIABLES" ,
136 will choose new behaviour when applicable.
137 \*(OB flags what will vanish, and enabling
141 enables obsoletion warnings.
145 \*(UA is a mail processing system with a command syntax reminiscent of
147 with lines replaced by messages.
148 It is intended to provide the functionality of the POSIX
150 command, but is MIME capable and optionally offers extensions for
151 line editing, S/MIME, SMTP and POP3 among others.
152 It is usable as a mail batch language.
154 .\" .Ss "Options" {{{
157 .Bl -tag -width ".Fl _ Ar _ddr"
160 Explicitly control which of the
162 shall be loaded: if the letter
164 is (case-insensitively) part of the
168 is loaded, likewise the letter
170 controls loading of the user's personal
172 file, whereas the letters
176 explicitly forbid loading of any resource files.
177 This option should be used by scripts: to avoid environmental noise they
180 from any configuration files and create a script-local environment,
181 explicitly setting any of the desired
182 .Sx "INTERNAL VARIABLES"
185 This option overrides
192 command for the given user email
194 after program startup is complete.
195 Being a special incarnation of
197 macros for the purpose of bundling longer-lived settings, activating
198 such an email account also switches to the accounts
204 Attach the given file to the message.
205 The same filename conventions as described in the section
207 apply: shell word expansion is restricted to the tilde
211 not be accessible but contain a
213 character, then anything after the
215 is assumed to specify the input character set and anything before
217 the filename: this is the only option to specify the input character set
218 (and don't perform any character set conversion) for text attachments
219 from the command line, not using the
221 tilde escape command.
225 Make standard input and standard output line-buffered.
229 Send a blind carbon copy to
232 May be used multiple times, but it is also possible to give
233 a comma-separated list of receivers in a single argument, proper quoting
235 .Ql -b """qrec1 , rec2,rec3, Ex <am@ple>""" .
237 .Sx "On sending mail, and non-interactive mode" .
241 Send carbon copies to the given receiver(s).
242 May be used multiple times.
247 the internal variable
249 which enables debug messages and disables message delivery,
250 among others; effectively turns almost any operation into a dry-run.
256 and thus discard messages with an empty message part body.
257 This is useful for sending messages from scripts.
261 Just check if mail is present (in the specified or system
263 box): if yes, return an exit status of zero, a non-zero value otherwise.
264 To restrict the set of mails to consider in this evaluation a message
265 specification can be added with the option
270 Save the message to send in a file named after the local part of the
271 first recipient's address (instead of in
276 Read in the contents of the user's
278 (or the specified file) for processing;
279 when \*(UA is quit, it writes undeleted messages back to this file
283 Some special conventions are recognized for the optional
285 argument which are documented for the
290 is not a argument to the flag
292 but is instead taken from the command line after option processing has
296 that starts with a hyphen, prefix it with a (relative) path, as in
297 .Ql ./-hyphenbox.mbox .
301 Display a summary of the
303 of all messages in the specified or system
306 A configurable summary view is available via the
312 Show a short usage summary.
313 Because of widespread use a
315 argument will have the same effect.
321 to ignore tty interrupt signals.
324 .It Fl L Ar spec-list
325 Display a summary of all
327 of only those messages in the specified or system
329 box that match the given
333 .Sx "Specifying messages"
340 option has been given in addition no header summary is produced,
341 but \*(UA will instead indicate via its exit status whether
347 note that any verbose output is suppressed in this mode and must instead
348 be enabled explicitly (e.g., by using the option
353 Special send mode that will flag standard input with the MIME
357 and use it as the main message body.
358 \*(ID Using this option will bypass processing of
359 .Va message-inject-head ,
362 .Va message-inject-tail .
368 Special send mode that will MIME classify the specified
370 and use it as the main message body.
371 \*(ID Using this option will bypass processing of
372 .Va message-inject-head ,
375 .Va message-inject-tail .
383 and thus inhibit initial display of message headers when reading mail or
384 editing a mail folder.
388 Standard flag that inhibits reading the system wide
393 allows more control over the startup sequence; also see
394 .Sx "Resource files" .
398 Special send mode that will initialize the message body with the
399 contents of the specified
401 which may be standard input
403 only in non-interactive context.
409 Any folder opened will be in read-only mode.
412 .It Fl r Ar from-addr
415 is a valid address then it specifies the envelope sender address to be
416 passed to a file-based
418 (Mail-Transfer-Agent) as
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 file-based
430 will also be assigned to the
433 .Ql -Sfrom=from-addr ) ,
434 therefore affecting possible SMTP
436 data transfer; note this assignment does not cause value fixation.
438 If instead an empty string is passed as
440 then the content of the variable
442 will be evaluated and used for this purpose whenever the
445 Note that \*(UA by default, without
447 that is, neither passes
451 flags to a file-based MTA by itself.
454 .It Fl S Ar var Ns Op = Ns value
458 iable and, in case of a non-boolean variable which has a value, assign
461 Even though variables (see
462 .Sx "INTERNAL VARIABLES" )
466 may be overwritten from within resource files,
467 the command line setting will be reestablished after all resource files
472 Specify the subject of the to-be-sent message.
476 The message given (on standard input) is expected to contain, separated
477 from the message body by an empty line, a message header with
482 fields giving its recipients, which will be added to any recipients
483 specified on the command line.
484 If a message subject is specified via
486 then it'll be used in favour of one given on the command line.
504 .Ql Mail-Followup-To: ,
505 by default created automatically dependent on message context, will
506 be used if specified (a special address massage will however still occur
508 Any other (even custom) header field is passed through entirely
509 unchanged, and in conjunction with the option
511 it is even possible to embed
518 Initially read the primary system mailbox of
520 appropriate privileges presumed; effectively identical to
532 ting the internal variable
534 enables display of some informational context messages.
535 Using it twice increases the level of verbosity.
541 to the list of commands to be executed before normal operation starts.
545 .Va batch-exit-on-error ;
546 the only possibility to execute commands in non-interactive mode when
547 reading startup files is actively prohibited.
553 even if not in interactive mode.
554 This can be used to, e.g., automatically format the composed message
555 text before sending the message:
556 .Bd -literal -offset indent
557 $ ( echo 'line one. Word. Word2.'; \e
558 echo '~| /usr/bin/fmt -tuw66' ) |\e
559 LC_ALL=C \*(uA -:/ -d~ bob@exam.ple
565 In batch mode the full set of commands is available, just like in
566 interactive mode, and diverse variable settings and internal states are
567 adjusted for batch necessities, e.g., it
582 is enabled in compose mode.
583 The following prepares an email message in a batched dry run:
584 .Bd -literal -offset indent
585 $ LC_ALL=C printf 'm bob\en~s ubject\enText\en~.\enx\en' | \e
586 LC_ALL=C \*(uA -:/ -d# -X'alias bob bob@exam.ple'
591 This flag forces termination of option processing in order to prevent
594 It also forcefully puts \*(UA into send mode, see
595 .Sx "On sending mail, and non-interactive mode" .
599 In the above list of supported command line options,
603 are implemented by means of
605 ting the respective option, as via
608 .Op Ar mta-option ...
610 arguments that are given at the end of the command line after a
612 separator will be passed through to a file-based
614 (Mail-Transfer-Agent) and persist for an entire (interactive) session
615 \(en if the setting of
617 allows their recognition; no such constraints apply to the variable
621 .\" .Ss "A starter" {{{
624 \*(UA is a direct descendant of
626 Mail, a successor of the Research
629 .Dq was there from the start
634 Mail reference manual begins with the following words:
636 .Bd -ragged -offset indent
637 Mail provides a simple and friendly environment for sending and
639 It divides incoming mail into its constituent messages and allows the
640 user to deal with them in any order.
641 In addition, it provides a set of
643 -like commands for manipulating messages and sending mail.
644 Mail offers the user simple editing capabilities to ease the composition
645 of outgoing messages, as well as providing the ability to define and
646 send to names which address groups of users.
650 \*(UA is thus the user side of the
652 mail system, whereas the system side (Mail-Transfer-Agent, MTA) was
653 traditionally taken by
655 and most MTAs provide a binary of this name for compatibility purposes.
660 of \*(UA then the system side is not a mandatory precondition for mail
664 Because \*(UA strives for compliance with POSIX
666 it is likely that some configuration settings have to be adjusted before
667 using it is a smooth experience.
670 file already bends those standard imposed settings a bit towards more
671 user friendliness and safety, e.g., it
673 s the internal variables
677 in order to suppress the automatic moving of messages to
679 that would otherwise occur (see
680 .Sx "Message states" )
683 to not remove empty files in order not to mangle file permissions when
684 files eventually get recreated (\*(UA actively manages the file mode
687 upon program startup).
691 .Sx "INTERNAL VARIABLES" ,
692 isn't set by default so that file grouping (via the
694 prefix as documented for
696 is not functional by default.
699 contains some suggestions.
702 .\" .Ss "On sending mail, and non-interactive mode" {{{
703 .Ss "On sending mail, and non-interactive mode"
705 To send a message to one or more people, using a local or a builtin
707 (Mail-Transfer-Agent) transport to actually deliver the generated mail
708 message, \*(UA can be invoked with arguments which are the names of
709 people to whom the mail will be sent, and the command line options
713 can be used to add (blind) carbon copy receivers:
715 .Bd -literal -offset indent
716 $ \*(uA -s ubject -a ttach.txt bill@exam.ple
717 # But... try it in an isolated dry-run mode first
718 $ LC_ALL=C \*(uA -:/ -d -vv -Ssendwait \e
719 -b bcc@exam.ple -c cc@exam.ple -. \e
720 '(Lovely) Bob <bob@exam.ple>' eric@exam.ple
722 $ LC_ALL=C \*(uA -:/ -d -vv -Sv15-compat -Ssendwait \e
723 -S 'mta=smtps://mylogin@exam.ple:465' -Ssmtp-auth=login \e
724 -S 'from=scriptreply@exam.ple' \e
730 If standard input is a terminal rather than the message to be sent,
731 the user is expected to type in the message contents.
732 In this compose mode \*(UA treats lines beginning with the character
734 special \(en these are so-called
736 which can be used to read in files, process shell commands, add and edit
737 attachments and more; e.g., the tilde escape
739 will start the text editor to revise the message in it's current state,
741 allows editing of the most important message headers and
743 gives an overview of available tilde escapes.
747 at the beginning of an empty line leaves compose mode and causes the
748 message to be sent, whereas typing
751 twice will abort the current letter (saving its contents in the file
757 Messages are sent asynchronously, without supervision, unless the variable
759 is set, therefore send errors are not recognizable until then.
765 .Sx "INTERNAL VARIABLES"
766 can be used to alter default behavior; e.g.,
771 will automatically startup a text editor when compose mode is entered,
773 will cause the user to be prompted actively for carbon-copy recipients
776 option will allow leaving compose mode by writing a line consisting
782 hook macros may be set to automatically adjust some settings dependent
783 on receiver, sender or subject contexts.
786 Especially for using public mail provider accounts with the SMTP
788 it is often necessary to set
790 and saving a copy of sent messages in a
792 may be desirable \(en as for most mailbox file targets some special
793 syntax conventions are recognized (see the
795 command for more on that).
798 for the purpose of arranging a complete environment of settings that can
799 be switched to with a single command or command line option may be
802 contains example configurations for sending messages via some of the
803 well-known public mail providers and also gives a compact overview on
804 how to setup a secure SSL/TLS environment).
809 sandbox dry-run tests first will prove correctness.
813 .Sx "On URL syntax and credential lookup"
814 will spread light on the different ways of how to specify user email
815 account credentials, the
817 variable chains, and accessing protocol-specific resources,
820 goes into the details of character encoding and how to use them for
821 representing messages and MIME part contents by specifying them in
823 and reading the section
824 .Sx "The mime.types files"
825 should help to understand how the MIME-type of outgoing attachments are
826 classified, and what can be done for fine-tuning.
829 Message recipients (as specified on the command line or defined in
834 may not only be email addressees but can also be names of mailboxes and
835 even complete shell command pipe specifications.
838 is not set then only network addresses (see
840 for a description of mail addresses) and plain user names (including MTA
841 aliases) may be used, other types will be filtered out, giving a warning
844 .\" When changing any of the following adjust any RECIPIENTADDRSPEC;
845 .\" grep the latter for the complete picture
849 is set then extended recipient addresses will optionally be accepted:
850 Any name which starts with a vertical bar
852 character specifies a command pipe \(en the command string following the
854 is executed and the message is sent to its standard input;
855 Likewise, any name that starts with the character solidus
857 or the character sequence dot solidus
859 is treated as a file, regardless of the remaining content.
860 Any other name which contains an at sign
862 character is treated as a network address;
863 Any other name which starts with a plus sign
865 character specifies a mailbox name;
866 Any other name which contains a solidus
868 character but no exclamation mark
872 character before also specifies a mailbox name;
873 What remains is treated as a network address.
875 .Bd -literal -offset indent
876 $ echo bla | \*(uA -Sexpandaddr -s test ./mbox.mbox
877 $ echo bla | \*(uA -Sexpandaddr -s test '|cat >> ./mbox.mbox'
878 $ echo safe | LC_ALL=C \e
879 \*(uA -:/ -Sv15-compat -Ssendwait -Snosave \e
880 -Sexpandaddr=fail,-all,+addr -s test \e
885 It is possible to create personal distribution lists via the
887 command, so that, for instance, the user can send mail to
889 and have it go to a group of people.
890 These aliases have nothing in common with the system wide aliases that
891 may be used by the MTA, which are subject to the
895 and are often tracked in a file
901 Personal aliases will be expanded by \*(UA before the message is sent,
902 and are thus a convenient alternative to specifying each addressee by
906 .Dl alias cohorts bill jkf mark kridle@ucbcory ~/mail/cohorts.mbox
909 To avoid environmental noise scripts should
911 \*(UA from any configuration files and create a script-local
912 environment, ideally with the command line options
914 to disable any configuration file in conjunction with repetitions of
916 to specify variables:
918 .Bd -literal -offset indent
920 \*(uA -:/ -Sv15-compat -Ssendwait -Snosave \e
921 -Sexpandaddr=fail,-all,+addr \e
922 -S 'mta=smtps://mylogin@exam.ple:465' -Ssmtp-auth=login \e
923 -S 'from=scriptreply@exam.ple' \e
924 -s 'subject' -a attachment_file \e
925 -. "Recipient 1 <rec1@exam.ple>" rec2@exam.ple \e
930 In interactive mode, which is introduced in the next section, messages
931 can be sent by calling the
933 command with a list of recipient addresses \(em the semantics are
934 completely identical to non-interactive message sending:
936 .Bd -literal -offset indent
937 $ \*(uA -d -Squiet -Semptystart
938 "/var/spool/mail/user": 0 messages
939 ? mail "Recipient 1 <rec1@exam.ple>", rec2@exam.ple
940 ? # Will do the right thing (tm)
941 ? m rec1@exam.ple rec2@exam.ple
945 .\" .Ss "On reading mail, and interactive mode" {{{
946 .Ss "On reading mail, and interactive mode"
948 When invoked without addressees \*(UA enters interactive mode in which
950 When used like that the user's system
954 for an in-depth description of the different mailbox types that exist)
955 is read in and a one line header of each message therein is displayed.
956 The visual style of this summary of
958 can be adjusted through the variable
960 and the possible sorting criterion via
962 If the initially opened mailbox is empty \*(UA will instead exit
963 immediately (after displaying a message) unless the variable
972 will give a listing of all available commands and
974 will give a summary of some common ones.
975 If the \*(OPal documentation strings are available one can type
977 and see the actual expansion of
979 and what it's purpose is, i.e., commands can be abbreviated
980 (note that POSIX defines some abbreviations, so that the alphabetical
981 order of commands doesn't necessarily relate to the abbreviations; it is
982 possible to define overwrites with the
987 Messages are given numbers (starting at 1) which uniquely identify
988 messages; the current message \(en the
990 \(en will either be the first new message, or the first unread message,
991 or the first message of the mailbox; the option
993 will instead cause usage of the last message for this purpose.
998 ful of header summaries containing the
1002 will display only the summaries of the given messages, defaulting to the
1006 Message content can be displayed on the users' terminal with the
1010 If instead the command
1012 is used, only the first
1014 of a message will be shown.
1015 By default the current message
1017 is displayed, but like with many other commands it is possible to give
1018 a fancy message specification (see
1019 .Sx "Specifying messages" ) ,
1022 will display all unread messages,
1027 will type the messages 1 and 5,
1029 will type the messages 1 through 5, and
1033 will display the last and the next message, respectively.
1036 (a more substantial alias of the standard command
1038 will display a header summary of the given message specification list
1039 instead of their content, e.g., the following will search for subjects:
1042 .Dl from "'@Some subject to search for'"
1045 In the default setup all header fields of a message will be
1047 d, but this can be changed: either by blacklisting a list of fields via
1049 or by whitelisting only a given list with the
1052 .Ql Ic \:retain Ns \0from_ date from to cc subject .
1053 In order to display all header fields of a message regardless of
1054 currently active ignore or retain lists, use the commands
1060 controls whether and when \*(UA will use the configured
1062 for display instead of directly writing to the user terminal
1064 (generally speaking).
1065 Note that historically the global
1067 not only adjusts the list of displayed headers, but also sets
1071 Dependent upon the configuration a line editor (see the section
1072 .Sx "On terminal control and line editor" )
1073 aims at making user experience with the many
1076 When reading the system
1082 specified a mailbox explicitly prefixed with the special
1084 modifier (propagating the mailbox to a primary one) then messages which
1085 have been read will be moved to a secondary mailbox, the user's
1087 file, automatically when the mailbox is left, either by changing the
1088 active mailbox or by quitting \*(UA (also see
1089 .Sx "Message states" )
1090 \(en this automatic moving from a system or primary to the secondary
1091 mailbox is not performed when the variable
1096 After examining a message the user can also
1100 to the sender and all recipients or
1102 exclusively to the sender(s).
1103 Messages can also be
1105 ed (shorter alias is
1107 Note that when replying to or forwarding a message recipient addresses
1108 will be stripped from comments and names unless the option
1111 Deletion causes \*(UA to forget about the message;
1112 This is not irreversible, though, one can
1114 the message by giving its number,
1115 or the \*(UA session can be ended by giving the
1120 To end a mail processing session one may either issue
1122 to cause a full program exit, which possibly includes
1123 automatic moving of read messages to
1125 as well as updating the \*(OPal line editor
1129 instead in order to prevent any of these actions.
1132 .\" .Ss "HTML mail and MIME attachments" {{{
1133 .Ss "HTML mail and MIME attachments"
1135 Messages which are HTML-only get more and more common and of course many
1136 messages come bundled with a bouquet of MIME attachments.
1137 Whereas \*(UA \*(OPally supports a simple HTML-to-text converter to deal
1138 with HTML messages (see
1139 .Sx "The mime.types files" ) ,
1140 it normally can't deal with any of these itself, but instead programs
1141 need to become registered to deal with specific MIME types or file
1143 These programs may either prepare plain text versions of their input
1144 in order to enable \*(UA to display the content on the terminal,
1145 or display the content themselves, for example in a graphical window.
1148 To install an external handler program for a specific MIME type set an
1150 .Va pipe-TYPE/SUBTYPE
1151 variable; to instead define a handler for a specific file extension set
1154 variable \(en these handlers take precedence.
1155 \*(OPally \*(UA supports mail user agent configuration as defined in
1156 RFC 1524; this mechanism, documented in the section
1157 .Sx "The Mailcap files" ,
1158 will be queried for display or quote handlers if none of the former two
1159 .\" TODO v15-compat "will be" -> "is"
1160 did; it will be the sole source for handlers of other purpose.
1161 A last source for handlers may be the MIME type definition itself, if
1162 the \*(UA specific type-marker extension was used when defining the type
1165 (Many of the builtin MIME types do so by default.)
1169 .Va mime-counter-evidence
1170 can be set to improve dealing with faulty MIME part declarations as are
1171 often seen in real-life messages.
1172 E.g., to display a HTML message inline (that is, converted to a more
1173 fancy plain text representation than the builtin converter is capable to
1174 produce) with either of the text-mode browsers
1178 teach \*(UA about MathML documents and make it display them as plain
1179 text, and to open PDF attachments in an external PDF viewer,
1180 asynchronously and with some other magic attached:
1182 .Bd -literal -offset indent
1183 if $features !@ +filter-html-tagsoup
1184 #set pipe-text/html='elinks -force-html -dump 1'
1185 set pipe-text/html='lynx -stdin -dump -force_html'
1186 # Display HTML as plain text instead
1187 #set pipe-text/html=@
1189 mimetype '@ application/mathml+xml mathml'
1190 wysh set pipe-application/pdf='@&=@ \e
1191 trap "rm -f \e"${NAIL_FILENAME_TEMPORARY}\e"" EXIT;\e
1192 trap "trap \e"\e" INT QUIT TERM; exit 1" INT QUIT TERM;\e
1193 mupdf "${NAIL_FILENAME_TEMPORARY}"'
1197 Note: special care must be taken when using such commands as mail
1198 viruses may be distributed by this method: if messages of type
1199 .Ql application/x-sh
1200 or files with the extension
1202 were blindly filtered through the shell, for example, a message sender
1203 could easily execute arbitrary code on the system \*(UA is running on.
1204 For more on MIME, also in respect to sending of messages, see the
1206 .Sx "The mime.types files" ,
1207 .Sx "The Mailcap files"
1212 .\" .Ss "Mailing lists" {{{
1215 \*(UA offers some support to ease handling of mailing lists.
1218 promotes all given arguments to known mailing lists, and
1220 sets their subscription attribute, creating them first as necessary.
1225 automatically, but only resets the subscription attribute.)
1226 Using the commands without arguments will show (a subset of) all
1227 currently defined mailing lists.
1232 can be used to mark out messages with configured list addresses
1233 in the header display.
1236 \*(OPally mailing lists may also be specified as (extended) regular
1237 expressions, which allows matching of many addresses with a single
1239 However, all fully qualified list addresses are matched via a fast
1240 dictionary, whereas expressions are placed in (a) list(s) which is
1241 (are) matched sequentially.
1243 .Bd -literal -offset indent
1244 set followup-to followup-to-honour=ask-yes reply-to-honour=ask-yes
1245 wysh mlist a1@b1.c1 a2@b2.c2 '.*@lists\e.c3$'
1246 mlsubscribe a4@b4.c4 exact@lists.c3
1251 .Va followup-to-honour
1253 .Ql Mail-\:Followup-\:To:
1254 header is honoured when the message is being replied to (via
1260 controls whether this header is created when sending mails; it will be
1261 created automatically for a couple of reasons, too, like when the
1263 .Dq mailing list specific
1268 is used to respond to a message with its
1269 .Ql Mail-Followup-To:
1273 A difference in between the handling of known and subscribed lists is
1274 that the address of the sender is usually not part of a generated
1275 .Ql Mail-Followup-To:
1276 when addressing the latter, whereas it is for the former kind of lists.
1277 Usually because there are exceptions: say, if multiple lists are
1278 addressed and not all of them are subscribed lists.
1280 For convenience \*(UA will, temporarily, automatically add a list
1281 address that is presented in the
1283 header of a message that is being responded to to the list of known
1285 Shall that header have existed \*(UA will instead, dependent on the
1287 .Va reply-to-honour ,
1290 for this purpose in order to accept a list administrators' wish that
1291 is supposed to have been manifested like that (but only if it provides
1292 a single address which resides on the same domain as what is stated in
1296 .\" .Ss "Resource files" {{{
1297 .Ss "Resource files"
1299 Upon startup \*(UA reads in several resource files:
1301 .Bl -tag -width ".It Pa _AIL_EXTRA_R_"
1304 System wide initialization file.
1305 Reading of this file can be suppressed, either by using the
1309 command line options, or by setting the
1312 .Ev NAIL_NO_SYSTEM_RC .
1316 File giving initial commands.
1317 A different file can be chosen by setting the
1321 Reading of this file can be suppressed with the
1323 command line option.
1325 .It Va NAIL_EXTRA_RC
1326 Can be used to define an optional startup file to be read after all
1327 other resource files.
1328 It can be used to specify settings that are not understood by other
1330 implementations, for example.
1331 This variable is only honoured when defined in a resource file, e.g.,
1333 .Sx "INTERNAL VARIABLES" .
1337 The content of these files is interpreted as follows:
1340 .Bl -bullet -compact
1342 A lines' leading whitespace is removed.
1344 Empty lines are ignored.
1346 Any other line is interpreted as a command.
1347 It may be spread over multiple input lines if the newline character is
1349 by placing a reverse solidus character
1351 as the last character of the line; whereas any leading whitespace of
1352 follow lines is ignored, trailing whitespace before a escaped newline
1353 remains in the input.
1355 If the line (content) starts with the number sign
1357 then it is a comment-command \(en a real command! \(en and also ignored.
1358 This command is the only form of comment that is understood.
1362 Unless \*(UA is about to enter interactive mode syntax errors that occur
1363 while loading these files are treated as errors and cause program exit.
1364 More files with syntactically equal content can be
1366 The following, saved in a file, would be an examplary content:
1368 .Bd -literal -offset indent
1369 # This line is a comment command. And y\e
1370 es, it is really continued here.
1377 .\" .Ss "Character sets" {{{
1378 .Ss "Character sets"
1380 \*(OP \*(UA detects the character set of the terminal by using
1381 mechanisms that are controlled by the
1386 should give an overview); the \*(UA internal variable
1388 will be set to the detected terminal character set accordingly
1389 and will thus show up in the output of the commands
1395 However, a user supplied
1397 value is not overwritten by this detection mechanism: this
1399 must be used if the detection doesn't work properly,
1400 and it may be used to adjust the name of the locale character set.
1401 E.g., on BSD systems one may use a locale with the character set
1402 ISO8859-1, which is not a valid name for this character set; to be on
1403 the safe side, one may set
1405 to the correct name, which is ISO-8859-1.
1408 Note that changing the value doesn't mean much beside that,
1409 since several aspects of the real character set are implied by the
1410 locale environment of the system,
1411 and that stays unaffected by the content of an overwritten
1414 (This is mostly an issue when interactively using \*(UA, though.
1415 It is actually possible to send mail in a completely
1417 locale environment, an option that \*(UA's test-suite uses excessively.)
1420 If no character set conversion capabilities have been compiled into
1423 doesn't include the term
1427 will be the only supported character set,
1428 it is simply assumed that it can be used to exchange 8-bit messages,
1429 and the rest of this section does not apply;
1430 it may however still be necessary to explicitly set it if automatic
1431 detection fails, since in that case it defaults to the mentioned
1432 .\" (Keep in SYNC: ./nail.1:"Character sets", ./nail.h:CHARSET_*!)
1436 When reading messages, their text is converted into
1438 as necessary in order to display them on the users terminal.
1439 Unprintable characters and invalid byte sequences are detected
1440 and replaced by proper substitution characters (unless the variable
1442 was set once \*(UA was started).
1444 .Va charset-unknown-8bit
1445 to deal with another hairy aspect of message interpretation.
1448 When sending messages all their parts and attachments are classified.
1449 Whereas no character set conversion is performed on those parts which
1450 appear to be binary data,
1451 the character set being used must be declared within the MIME header of
1452 an outgoing text part if it contains characters that do not conform to
1453 the set of characters that are allowed by the email standards.
1454 Permissible values for character sets can be declared using the
1458 which defines a catch-all last-resort fallback character set that is
1459 implicitly appended to the list of character-sets in
1463 When replying to a message and the variable
1464 .Va reply-in-same-charset
1465 is set then the character set of the message being replied to is tried
1467 And it is also possible to make \*(UA work even more closely related to
1468 the current locale setting automatically by using the variable
1469 .Va sendcharsets-else-ttycharset ,
1470 please see there for more information.
1473 All the specified character sets are tried in order unless the
1474 conversion of the part or attachment succeeds.
1475 If none of the tried (8-bit) character sets is capable to represent the
1476 content of the part or attachment,
1477 then the message will not be sent and its text will optionally be
1481 In general, if the message
1482 .Dq Cannot convert from a to b
1483 appears, either some characters are not appropriate for the currently
1484 selected (terminal) character set,
1485 or the needed conversion is not supported by the system.
1486 In the first case, it is necessary to set an appropriate
1488 locale and/or the variable
1492 The best results are usually achieved when \*(UA is run in a UTF-8
1493 locale on a UTF-8 capable terminal, in which case the full Unicode
1494 spectrum of characters is available.
1495 In this setup characters from various countries can be displayed,
1496 while it is still possible to use more simple character sets for sending
1497 to retain maximum compatibility with older mail clients.
1500 On the other hand the POSIX standard defines a locale-independent 7-bit
1501 .Dq portable character set
1502 that should be used when overall portability is an issue, the even more
1503 restricted subset named
1504 .Dq portable filename character set
1505 consisting of A-Z, a-z, 0-9, period
1514 .\" .Ss "Message states" {{{
1515 .Ss "Message states"
1517 \*(UA differentiates in between several different message states;
1518 the current state will be reflected in header summary displays if
1520 is configured to do so (via the internal variable
1522 and messages can also be selected and be acted upon depending on their
1524 .Sx "Specifying messages" ) .
1525 When operating on the system
1527 box or in primary mailboxes opened with the special prefix
1531 special actions, like the automatic moving of messages to the secondary
1533 mailbox may be applied when the mailbox is left (also implicitly via
1534 a successful exit of \*(UA, but not if the special command
1536 is used) \(en however, because this may be irritating to users which
1539 mail-user-agents, the default global
1545 variables in order to suppress this behaviour.
1547 .Bl -tag -width ".It Ql _reserved"
1549 Message has neither been viewed nor moved to any other state.
1550 Such messages are retained even in the primary system mailbox.
1553 Message has neither been viewed nor moved to any other state, but the
1554 message was present already when the mailbox has been opened last:
1555 Such messages are retained even in the primary system mailbox.
1558 The message has been processed by one of the following commands:
1578 commands may also cause the next message to be marked as read, depending
1584 command is used, messages that are in the primary system mailbox or in
1585 mailboxes which were opened with the special
1589 state when the mailbox is left will be saved in
1596 The message has been processed by one of the following commands:
1602 can be used to access such messages.
1605 The message has been processed by a
1607 command and it will be retained in its current location.
1610 The message has been processed by one of the following commands:
1616 command is used, messages that are in the primary system mailbox or in
1617 mailboxes which were opened with the special
1621 state when the mailbox is left will be deleted; they will be saved in
1629 .\" .Ss "Specifying messages" {{{
1630 .Ss "Specifying messages"
1637 can be given a list of message numbers as arguments to apply to a number
1638 of messages at once.
1641 deletes messages 1 and 2,
1644 will delete the messages 1 through 5.
1645 In sorted or threaded mode (see the
1649 will delete the messages that are located between (and including)
1650 messages 1 through 5 in the sorted/threaded order, as shown in the
1653 Multiple colon modifiers can be joined into one, e.g.,
1655 The following special message names exist:
1657 .Bl -tag -width ".It Ar _n_u"
1663 All old messages (any not in state
1688 All answered messages
1693 All messages marked as draft.
1695 \*(OP All messages classified as spam.
1697 \*(OP All messages with unsure spam classification.
1699 The current message, the so-called
1702 The message that was previously the current message.
1704 The parent message of the current message,
1705 that is the message with the Message-ID given in the
1707 field or the last entry of the
1709 field of the current message.
1711 The next previous undeleted message,
1712 or the next previous deleted message for the
1715 In sorted/threaded mode,
1716 the next previous such message in the sorted/threaded order.
1718 The next undeleted message,
1719 or the next deleted message for the
1722 In sorted/threaded mode,
1723 the next such message in the sorted/threaded order.
1725 The first undeleted message,
1726 or the first deleted message for the
1729 In sorted/threaded mode,
1730 the first such message in the sorted/threaded order.
1733 In sorted/threaded mode,
1734 the last message in the sorted/threaded order.
1738 selects the message addressed with
1742 is any other message specification,
1743 and all messages from the thread that begins at it.
1744 Otherwise it is identical to
1749 the thread beginning with the current message is selected.
1754 All messages that were included in the message list for the previous
1757 .It Ar / Ns Ar string
1758 All messages that contain
1760 in the subject field (case ignored).
1767 the string from the previous specification of that type is used again.
1769 .It Xo Op Ar @ Ns Ar name-list Ns
1772 All messages that contain the given case-insensitive search
1774 ession; if the \*(OPal regular expression (see
1776 support is available
1778 will be interpreted as (an extended) one if any of the
1780 (extended) regular expression characters is seen.
1782 .Ar @ Ns Ar name-list
1783 part is missing, the search is restricted to the subject field body,
1786 specifies a comma-separated list of header fields to search, as in
1788 .Dl '@to,from,cc@Someone i ought to know'
1790 In order to search for a string that includes a
1792 (commercial at) character the
1794 is effectively non-optional, but may be given as the empty string.
1795 Some special header fields may be abbreviated:
1809 respectively and case-insensitively.
1814 can be used to search in (all of) the header(s) of the message, and the
1823 can be used to perform full text searches \(en whereas the former
1824 searches only the body, the latter also searches the message header.
1826 This message specification performs full text comparison, but even with
1827 regular expression support it is almost impossible to write a search
1828 expression that savely matches only a specific address domain.
1829 To request that the content of the header is treated as a list of
1830 addresses, and to strip those down to the plain email address which the
1831 search expression is to be matched against, prefix the header name
1832 (abbreviation) with a tilde
1835 .Dl @~f@@a\e.safe\e.domain\e.match$
1839 .Dq any substring matches
1842 header, which will match addresses (too) even if
1844 is set (and POSIX says
1845 .Dq any address as shown in a header summary shall be matchable in this form ) ;
1848 variable is set, only the local part of the address is evaluated
1849 for the comparison, not ignoring case, and the setting of
1851 is completely ignored.
1852 For finer control and match boundaries use the
1854 search expression; the \*(OPal IMAP-style
1856 expression can also be used if substring matches are desired.
1860 \*(OP IMAP-style SEARCH expressions may also be used.
1861 This addressing mode is available with all types of folders;
1862 \*(UA will perform the search locally as necessary.
1863 Strings must be enclosed by double quotes
1865 in their entirety if they contain white space or parentheses;
1866 within the quotes, only reverse solidus
1868 is recognized as an escape character.
1869 All string searches are case-insensitive.
1870 When the description indicates that the
1872 representation of an address field is used,
1873 this means that the search string is checked against both a list
1876 .Bd -literal -offset indent
1877 (\*qname\*q \*qsource\*q \*qlocal-part\*q \*qdomain-part\*q)
1882 and the addresses without real names from the respective header field.
1883 These search expressions can be nested using parentheses, see below for
1887 .Bl -tag -compact -width ".It Ar _n_u"
1888 .It Ar ( criterion )
1889 All messages that satisfy the given
1891 .It Ar ( criterion1 criterion2 ... criterionN )
1892 All messages that satisfy all of the given criteria.
1894 .It Ar ( or criterion1 criterion2 )
1895 All messages that satisfy either
1900 To connect more than two criteria using
1902 specifications have to be nested using additional parentheses,
1904 .Ql (or a (or b c)) ,
1908 .Ql ((a or b) and c) .
1911 operation of independent criteria on the lowest nesting level,
1912 it is possible to achieve similar effects by using three separate
1916 .It Ar ( not criterion )
1917 All messages that do not satisfy
1919 .It Ar ( bcc \*q Ns Ar string Ns Ar \*q )
1920 All messages that contain
1922 in the envelope representation of the
1925 .It Ar ( cc \*q Ns Ar string Ns Ar \*q )
1926 All messages that contain
1928 in the envelope representation of the
1931 .It Ar ( from \*q Ns Ar string Ns Ar \*q )
1932 All messages that contain
1934 in the envelope representation of the
1937 .It Ar ( subject \*q Ns Ar string Ns Ar \*q )
1938 All messages that contain
1943 .It Ar ( to \*q Ns Ar string Ns Ar \*q )
1944 All messages that contain
1946 in the envelope representation of the
1949 .It Ar ( header name \*q Ns Ar string Ns Ar \*q )
1950 All messages that contain
1955 .It Ar ( body \*q Ns Ar string Ns Ar \*q )
1956 All messages that contain
1959 .It Ar ( text \*q Ns Ar string Ns Ar \*q )
1960 All messages that contain
1962 in their header or body.
1963 .It Ar ( larger size )
1964 All messages that are larger than
1967 .It Ar ( smaller size )
1968 All messages that are smaller than
1972 .It Ar ( before date )
1973 All messages that were received before
1975 which must be in the form
1979 denotes the day of the month as one or two digits,
1981 is the name of the month \(en one of
1982 .Ql Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ,
1985 is the year as four digits, e.g.,
1989 All messages that were received on the specified date.
1990 .It Ar ( since date )
1991 All messages that were received since the specified date.
1992 .It Ar ( sentbefore date )
1993 All messages that were sent on the specified date.
1994 .It Ar ( senton date )
1995 All messages that were sent on the specified date.
1996 .It Ar ( sentsince date )
1997 All messages that were sent since the specified date.
1999 The same criterion as for the previous search.
2000 This specification cannot be used as part of another criterion.
2001 If the previous command line contained more than one independent
2002 criterion then the last of those criteria is used.
2006 .\" .Ss "On URL syntax and credential lookup" {{{
2007 .Ss "On URL syntax and credential lookup"
2009 \*(IN For accessing protocol-specific resources usage of Uniform
2010 Resource Locators (URL, RFC 1738) has become omnipresent.
2011 \*(UA expects and understands URLs in the following form;
2014 denote optional parts, optional either because there also exist other
2015 ways to define the information in question or because support of the
2016 part is protocol-specific (e.g.,
2018 is used by the IMAP protocol but not by POP3);
2023 are specified they must be given in URL percent encoded form (RFC 3986;
2031 .Dl PROTOCOL://[USER[:PASSWORD]@]server[:port][/path]
2034 Note that these \*(UA URLs most often don't conform to any real
2035 standard, but instead represent a normalized variant of RFC 1738 \(en
2036 they are not used in data exchange but only meant as a compact,
2037 easy-to-use way of defining and representing information in
2038 a well-known notation.
2041 Many internal variables of \*(UA exist in multiple versions, called
2042 variable chains for the rest of this document: the plain
2047 .Ql variable-USER@HOST .
2054 had been specified in the respective URL, otherwise it refers to the plain
2060 that had been found when doing the user chain lookup as is described
2063 will never be in URL percent encoded form, whether it came from an URL
2064 or not; i.e., values of
2065 .Sx "INTERNAL VARIABLES"
2066 must not be URL percent encoded.
2069 For example, whether an hypothetical URL
2070 .Ql smtp://hey%3Ayou@our.house
2071 had been given that includes a user, or whether the URL was
2072 .Ql smtp://our.house
2073 and the user had been found differently, to lookup the variable chain
2074 .Va smtp-use-starttls
2075 \*(UA first looks for whether
2076 .Ql smtp-\:use-\:starttls-\:hey:you@our.house
2077 is defined, then whether
2078 .Ql smtp-\:use-\:starttls-\:our.house
2079 exists before finally ending up looking at the plain variable itself.
2082 \*(UA obeys the following logic scheme when dealing with the
2083 necessary credential information of an account:
2089 has been given in the URL the variables
2093 are looked up; if no such variable(s) can be found then \*(UA will,
2094 when enforced by the \*(OPal variables
2095 .Va netrc-lookup-HOST
2102 specific entry which provides a
2104 name: this lookup will only succeed if unambiguous (one possible matching
2107 It is possible to load encrypted
2112 If there is still no
2114 then \*(UA will fall back to the user who is supposed to run \*(UA,
2115 the identity of which has been fixated during \*(UA startup and is
2116 known to be a valid user on the current host.
2119 Authentication: unless otherwise noted this will lookup the
2120 .Va PROTOCOL-auth-USER@HOST , PROTOCOL-auth-HOST , PROTOCOL-auth
2121 variable chain, falling back to a protocol-specific default should this
2127 has been given in the URL, then if the
2129 has been found through the \*(OPal
2131 that may have already provided the password, too.
2132 Otherwise the variable chain
2133 .Va password-USER@HOST , password-HOST , password
2134 is looked up and used if existent.
2136 Afterwards the complete \*(OPal variable chain
2137 .Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup
2141 cache is searched for a password only (multiple user accounts for
2142 a single machine may exist as well as a fallback entry without user
2143 but with a password).
2145 If at that point there is still no password available, but the
2146 (protocols') chosen authentication type requires a password, then in
2147 interactive mode the user will be prompted on the terminal.
2152 S/MIME verification works relative to the values found in the
2156 header field(s), which means that the values of
2157 .Va smime-sign , smime-sign-cert , smime-sign-include-certs
2159 .Va smime-sign-message-digest
2160 will not be looked up using the
2164 chains from above but instead use the corresponding values from the
2165 message that is being worked on.
2166 In unusual cases multiple and different
2170 combinations may therefore be involved \(en on the other hand those
2171 unusual cases become possible.
2172 The usual case is as short as:
2175 .Dl set mta=smtp://USER:PASS@HOST smtp-use-starttls \e
2176 .Dl \ \ \ \ smime-sign smime-sign-cert=+smime.pair
2181 contains complete example configurations.
2184 .\" .Ss "On terminal control and line editor" {{{
2185 .Ss "On terminal control and line editor"
2187 \*(OP Terminal control will be realized through one of the standard
2189 libraries, either the
2191 or, alternatively, the
2193 both of which will be initialized to work with the environment variable
2195 Terminal control will enhance or enable interactive usage aspects, e.g.,
2196 .Sx "Coloured display" ,
2197 and extend behaviour of the Mailx-Line-Editor (MLE), which may learn the
2198 byte-sequences of keys like the cursor and function keys, and which will
2199 automatically enter the so-called
2201 alternative screen shall the terminal support it.
2202 The internal variable
2204 can be used to overwrite settings or to learn (correct(ed)) keycodes.
2205 Actual interaction with the chosen library can be disabled completely by
2206 setting the internal variable
2207 .Va termcap-disable ;
2209 will be queried regardless, even if the \*(OPal support for the
2210 libraries has not been enabled at configuration time.
2213 \*(OP The builtin \*(UA Mailx-Line-Editor (MLE) should work in all
2214 environments which comply to the ISO C standard
2216 and will support wide glyphs if possible (the necessary functionality
2217 had been removed from ISO C, but was included in
2219 Prevent usage of a line editor in interactive mode by setting the
2221 .Va line-editor-disable .
2222 Especially if the \*(OPal terminal control support is missing setting
2223 entries in the internal variable
2225 will help shall the MLE misbehave, see there for more.
2226 The MLE can support a little bit of
2232 feature is available then input from line editor prompts will be saved
2233 in a history list that can be searched in and be expanded from.
2234 Such saving can be prevented by prefixing input with any amount of
2236 Aspects of history, like allowed content and maximum size, as well as
2237 whether history shall be saved persistently, can be configured with the
2241 .Va history-gabby-persist
2246 The MLE supports a set of editing and control commands.
2247 By default (as) many (as possible) of these will be assigned to a set of
2248 single-letter control codes, which should work on any terminal.
2251 command is available then the MLE commands can also be accessed freely
2252 by assigning the command name, which is shown in parenthesis in the list
2253 below, to any desired key-sequence, and the MLE will instead and also use
2255 to establish its builtin key bindings
2256 (more of them if the \*(OPal terminal control is available),
2257 an action which can then be suppressed completely by setting
2258 .Va line-editor-no-defaults .
2259 The following uses the
2261 ell-style quote notation that is documented in the introductional
2264 combinations not mentioned either cause job control signals or don't
2265 generate a (unique) keycode:
2269 .Bl -tag -compact -width "Ql _M"
2271 Go to the start of the line
2272 .Pf ( Cd mle-go-home ) .
2275 Move the cursor backward one character
2276 .Pf ( Cd mle-go-bwd ) .
2279 Forward delete the character under the cursor;
2280 quits \*(UA if used on the empty line unless the
2283 .Pf ( Cd mle-del-fwd ) .
2286 Go to the end of the line
2287 .Pf ( Cd mle-go-end ) .
2290 Move the cursor forward one character
2291 .Pf ( Cd mle-go-fwd ) .
2294 Cancel current operation, full reset.
2295 If there is an active history search or tabulator expansion then this
2296 command will first reset that, reverting to the former line content;
2297 thus a second reset is needed for a full reset in this case
2298 .Pf ( Cd mle-reset ) .
2301 Backspace: backward delete one character
2302 .Pf ( Cd mle-del-bwd ) .
2306 Horizontal tabulator:
2307 try to expand the word before the cursor, also supporting \*(UA
2310 .Pf ( Cd mle-complete ) .
2312 .Cd mle-quote-rndtrip .
2316 commit the current line
2317 .Pf ( Cd mle-commit ) .
2320 Cut all characters from the cursor to the end of the line
2321 .Pf ( Cd mle-snarf-end ) .
2325 .Pf ( Cd mle-repaint ) .
2328 \*(OP Go to the next history entry
2329 .Pf ( Cd mle-hist-fwd ) .
2336 \*(OP Go to the previous history entry
2337 .Pf ( Cd mle-hist-bwd ) .
2340 Toggle roundtrip mode shell quotes, where produced,
2342 .Pf ( Cd mle-quote-rndtrip ) .
2343 This setting is temporary, and will be forgotten once the command line
2347 \*(OP Complete the current line from (the remaining) older history entries
2348 .Pf ( Cd mle-hist-srch-bwd ) .
2351 \*(OP Complete the current line from (the remaining) newer history entries
2352 .Pf ( Cd mle-hist-srch-fwd ) .
2355 Paste the snarf buffer
2356 .Pf ( Cd mle-paste ) .
2363 .Pf ( Cd mle-snarf-line ) .
2366 Prompts for a Unicode character (its hexadecimal number) to be inserted
2367 .Pf ( Cd mle-prompt-char ) .
2368 Note this command needs to be assigned to a single-letter control code
2369 in order to become recognized and executed during input of
2370 a key-sequence (only four single-letter control codes can be used for
2371 that shortcut purpose); this control code is special-treated and can't
2372 be part of any other sequence, because any occurrence will perform the
2374 function immediately.
2377 Cut the characters from the one preceding the cursor to the preceding
2379 .Pf ( Cd mle-snarf-word-bwd ) .
2382 Move the cursor forward one word boundary
2383 .Pf ( Cd mle-go-word-fwd ) .
2386 Move the cursor backward one word boundary
2387 .Pf ( Cd mle-go-word-bwd ) .
2390 Escape: reset a possibly used multibyte character input state machine
2391 and \*(OPally a lingering, incomplete key binding
2392 .Pf ( Cd mle-cancel ) .
2393 This command needs to be assigned to a single-letter control code in
2394 order to become recognized and executed during input of a key-sequence
2395 (only four single-letter control codes can be used for that shortcut
2397 This control code may also be part of a multi-byte sequence, but if
2398 a sequence is active and the very control code is currently also an
2399 expected input, then it will first be consumed by the active sequence.
2414 Cut the characters from the one after the cursor to the succeeding word
2416 .Pf ( Cd mle-snarf-word-fwd ) .
2426 this will immediately reset a possibly active search etc.
2430 ring the audible bell.
2434 .\" .Ss "Coloured display" {{{
2435 .Ss "Coloured display"
2437 \*(OP \*(UA can be configured to support a coloured display and font
2438 attributes by emitting ANSI / ISO 6429 SGR (select graphic rendition)
2440 Usage of colours and font attributes solely depends upon the
2441 capability of the detected terminal type that is defined by the
2442 environment variable
2444 and which can be fine-tuned by the user via the internal variable
2448 On top of what \*(UA knows about the terminal the boolean variable
2450 defines whether the actually applicable colour and font attribute
2451 sequences should also be generated when output is going to be paged
2452 through the external program defined by the environment variable
2457 This is not enabled by default because different pager programs need
2458 different command line switches or other configuration in order to
2459 support those sequences.
2460 \*(UA however knows about some widely used pagers and in a clean
2461 environment it is often enough to simply set
2463 please refer to that variable for more on this topic.
2468 is set then any active usage of colour and font attribute sequences
2469 is suppressed, but without affecting possibly established
2474 To define and control colours and font attributes a single multiplexer
2475 command family exists:
2477 shows or defines colour mappings for the given colour type (e.g.,
2480 can be used to remove mappings of a given colour type.
2481 Since colours are only available in interactive mode, it may make
2482 sense to conditionalize the colour setup by encapsulating it with
2485 .Bd -literal -offset indent
2486 if terminal && $features =@ +colour
2487 colour iso view-msginfo ft=bold,fg=green
2488 colour iso view-header ft=bold,fg=red "from,subject"
2489 colour iso view-header fg=red
2491 uncolour iso view-header from,subject
2492 colour iso view-header ft=bold,fg=magenta,bg=cyan
2493 colour 256 view-header ft=bold,fg=208,bg=230 subject,from
2494 colour mono view-header ft=bold
2495 colour mono view-header ft=bold,ft=reverse subject,from
2499 .\" }}} (DESCRIPTION)
2502 .\" .Sh COMMANDS {{{
2505 Each command is typed on a line by itself,
2506 and may take arguments following the command word.
2507 Command names may be abbreviated, in which case the first command that
2508 matches the given prefix will be used.
2511 can be used to show the list of all commands, either alphabetically
2512 sorted or in prefix search order (these don't match, also because the
2513 POSIX standard prescribes a set of abbreviations); a more verbose
2514 listing will be produced if either of
2519 \*(OPally the command
2523 when given an argument, will show a documentation string for the
2524 command matching the expanded argument, as in
2526 which should be a shorthand of
2530 For commands which take message lists as arguments, the next message
2531 forward that satisfies the command's requirements will be used shall no
2532 explicit message list have been specified.
2533 If there are no messages forward of the current message,
2534 the search proceeds backwards,
2535 and if there are no good messages at all,
2536 \*(UA shows an error message and aborts the command.
2537 \*(ID Non-message-list arguments can be quoted using the following methods:
2540 .Bl -bullet -compact -offset indent
2542 An argument can be enclosed between paired double-quotes
2547 any white space, shell word expansion, or reverse solidus characters
2548 (except as described next) within the quotes are treated literally as
2549 part of the argument.
2550 A double-quote will be treated literally within single-quotes and vice
2552 Inside such a quoted string the actually used quote character can be
2553 used nonetheless by escaping it with a reverse solidus
2559 An argument that is not enclosed in quotes, as above, can usually still
2560 contain space characters if those spaces are reverse solidus escaped, as in
2564 A reverse solidus outside of the enclosing quotes is discarded
2565 and the following character is treated literally as part of the argument.
2570 Some commands which don't take message-list arguments can also be
2571 prefixed with the special keyword
2573 to choose \*(INible behaviour, and some new commands support only the
2574 new quoting style (without that keyword) and are flagged \*(NQ.
2575 In the future \*(UA will (mostly) use
2577 compatible argument parsing:
2578 Non-message-list arguments can be quoted using the following shell-style
2579 mechanisms: the escape character, single-quotes, double-quotes and
2580 dollar-single-quotes; any unquoted number sign
2582 starts a comment that ends argument processing.
2583 The overall granularity of error reporting and diagnostics, also
2584 regarding function arguments and their content, will improve.
2588 .Bl -bullet -compact -offset indent
2590 The literal value of any character can be preserved by preceding it
2591 with the escape character reverse solidus
2595 will cause variable expansion of the given name: \*(UA
2596 .Sx "INTERNAL VARIABLES"
2599 (shell) variables can be accessed through this mechanism, brace
2600 enclosing the name is supported.
2603 Arguments which are enclosed in
2604 .Ql 'single-\:quotes'
2605 retain their literal value.
2606 A single-quote cannot occur within single-quotes.
2609 The literal value of all characters enclosed in
2610 .Ql \(dqdouble-\:quotes\(dq
2611 is retained, with the exception of dollar
2613 which will cause variable expansion, as above, backquote (grave accent)
2615 (which not yet means anything special), reverse solidus
2617 which will escape any of the characters dollar
2619 (to prevent variable expansion), backquote (grave accent)
2623 (to prevent ending the quote) and reverse solidus
2625 (to prevent escaping, i.e., to embed a reverse solidus character as-is),
2626 but has no special meaning otherwise.
2629 Arguments enclosed in
2630 .Ql $'dollar-\:single-\:quotes'
2631 extend normal single quotes in that reverse solidus escape sequences are
2632 expanded as follows:
2634 .Bl -tag -compact -width "Ql \eNNN"
2640 an escape character.
2642 an escape character.
2654 emits a reverse solidus character.
2658 double quote (escaping is optional).
2660 eight-bit byte with the octal value
2662 (one to three octal digits), optionally with an additional
2665 A 0 byte will suppress further output for the quoted argument.
2667 eight-bit byte with the hexadecimal value
2669 (one or two hexadecimal characters).
2670 A 0 byte will suppress further output for the quoted argument.
2672 the Unicode / ISO-10646 character with the hexadecimal codepoint value
2674 (one to eight hexadecimal digits) \(em note that Unicode defines the
2675 maximum code to be ever supported as
2680 This escape is only supported in locales which support Unicode (see
2681 .Sx "Character sets" ) ,
2682 in other cases the sequence will remain unexpanded unless the given code
2683 point is ASCII compatible.
2684 The character NUL will suppress further output for the quoted argument.
2688 except it takes only one to four hexadecimal digits.
2693 This is a mechanism that allows usage of the non-printable (ASCII and
2694 compatible) control codes 0 to 31: to be able to create a printable
2695 representation the numeric value 64 is added to the control code of
2696 desire, and the resulting ASCII character set code point is then
2697 printed, e.g., BEL is
2698 .Ql 7 + 64 = 71 = G .
2699 Often circumflex notation is used for the visualization purpose, e.g,
2701 but the reverse solid notation has been standardized:
2703 The control code NUL
2705 ends argument processing without producing further output.
2707 Non-standard extension: expand the given variable name, as above.
2708 Brace enclosing the name is supported.
2710 Not yet supported, just to raise awareness: Non-standard extension.
2716 .Sy Compatibility notes:
2717 \*(ID Note these are new mechanisms which are not supported by all
2719 Round-tripping (feeding in things shown in list modes again) are not yet
2720 stable or possible at all.
2721 On new-style command lines it is wise to quote semicolon
2725 characters in order to ensure upward compatibility: the author would
2726 like to see things like
2727 .Ql ? echo $'trouble\etahead' | cat >> in_the_shell.txt
2729 .Ql ? top 2 5 10; type 3 22
2731 Before \*(UA will switch entirely to shell-style argument parsing there
2732 will be a transition phase where using
2734 will emit obsoletion warnings.
2735 E.g., the following are equivalent:
2737 .Bd -literal -offset indent
2738 mlist @any\e\e.where\e\e.example\e\e.com
2739 wysh mlist '@any\e.where\e.example\e.com' # This is a comment
2740 wysh mlist $'@any\e\e\ex2Ewhere\e\e.example\e\e\e56com' # A comment
2741 wysh mlist "@any\e.where\e.example\e.com"
2745 In any event an unquoted reverse solidus at the end of a command line is
2746 discarded and the next line continues the command.
2747 \*(ID Note that line continuation is handled before the above parsing is
2748 applied, i.e., the parsers documented above will see merged lines.
2749 Filenames, where expected, are subsequently subjected to the following
2750 transformations, in sequence:
2753 .Bl -bullet -compact -offset indent
2755 If the filename begins with an unquoted plus sign, and the
2757 variable is defined,
2758 the plus sign will be replaced by the value of the
2760 variable followed by a solidus.
2763 variable is unset or is set to null, the filename will be unchanged.
2766 Meta expansions are applied to the filename: a leading tilde
2768 character will be replaced by the expansion of
2770 except when followed by a valid user name, in which case the home
2771 directory of the given user is used instead.
2776 will be replaced by the expansion of the variable, if possible; \*(UA
2777 .Sx "INTERNAL VARIABLES"
2780 (shell) variables can be accessed through this mechanism, and the usual
2781 escape mechanism has to be applied to prevent interpretation.
2782 If the fully expanded filename results in multiple pathnames and the
2783 command is expecting only one file, an error results.
2785 In interactive context, in order to allow simple value acceptance (via
2787 arguments will usually be displayed in a properly quoted form, e.g., a file
2788 .Ql diet\e is \ecurd.txt
2790 .Ql 'diet\e is \ecurd.txt' .
2794 The following commands are available:
2796 .Bl -tag -width ".Ic _ccount"
2803 ) command which follows.
2807 The comment-command causes the entire line to be ignored.
2809 this really is a normal command which' purpose is to discard its
2812 indicating special character, which means that, e.g., trailing comments
2813 on a line are not possible.
2817 Goes to the next message in sequence and types it
2823 Display the preceding message, or the n'th previous message if given
2824 a numeric argument n.
2828 Show the current message number (the
2833 Show a brief summary of commands.
2834 \*(OP Given an argument a synopsis for the command in question is
2835 shown instead; commands can be abbreviated in general and this command
2836 can be used to see the full expansion of an abbreviation including the
2837 synopsis, try, e.g.,
2842 and see how the output changes.
2852 Interprets the remainder of the word as a macro name and passes it
2857 is a shorter synonym for
2858 .Ql call Ar mymacro .
2862 (ac) Creates, selects or lists (an) account(s).
2863 Accounts are special incarnations of
2865 macros and group commands and variable settings which together usually
2866 arrange the environment for the purpose of creating an email account.
2867 Different to normal macros settings which are covered by
2869 \(en here by default enabled! \(en will not be reverted before the
2874 (case-insensitive) always exists, and all but it can be deleted via
2877 Without arguments a listing of all defined accounts is shown.
2878 With one argument the given account is activated: the system
2880 box of that account will be activated (as via
2882 and a possibly installed
2885 The two argument form is identical to defining a macro as via
2887 .Bd -literal -offset indent
2889 set folder=~/mail MAIL=+syste.mbox record=+sent.mbox
2890 set from='myname@myisp.example (My Name)'
2891 set mta=smtp://mylogin@smtp.myisp.example
2897 (a) With no arguments, shows all currently-defined aliases.
2898 With one argument, shows that alias.
2899 With more than one argument,
2900 creates a new alias or appends to an existing one.
2902 can be used to delete aliases.
2906 (alt) Manage a list of alternate addresses / names of the active user,
2907 members of which will be removed from recipient lists when replying to
2910 variable is not set).
2911 If arguments are given the set of alternate names is replaced by them,
2912 without arguments the current set is displayed.
2916 Takes a message list and marks each message as having been answered.
2917 This mark has no technical meaning in the mail system;
2918 it just causes messages to be marked in the header summary,
2919 and makes them specially addressable.
2924 \*(OP\*(NQ The bind command extends the MLE (see
2925 .Sx "On terminal control and line editor" )
2926 with freely configurable key bindings.
2927 With one argument all bindings for the given context are shown,
2928 specifying an asterisk
2930 will show the bindings of all contexts; a more verbose listing will be
2931 produced if either of
2936 With two or more arguments a binding is (re)established:
2937 the first argument is the context to which the binding shall apply,
2938 the second argument is a comma-separated list of the
2940 which form the binding, and any remaining arguments form the expansion.
2941 To indicate that a binding shall not be auto-committed, but that the
2942 expansion shall instead be furtherly editable by the user, an at-sign
2944 (that will be removed) can be placed last in the expansion, from which
2945 leading and trailing whitespace will finally be removed.
2948 Contexts define when a binding applies, i.e., a binding won't be seen
2949 unless the context for which it is defined for is currently active.
2950 This is not true for the binding
2952 which always applies, but which will be searched secondarily to a more
2953 specialized context and may thus have some or all of its key bindings
2954 transparently replaced by equal bindings of more specialized contexts.
2955 The available contexts are
2957 which always applies, and
2959 which applies to compose-mode.
2963 which form the binding are specified as a comma-separated list of
2964 byte-sequences, where each list entry corresponds to one key(press).
2965 \*(OPally a list entry may, indicated by a leading colon character
2967 also refer to the name of a terminal capability;
2968 several dozen names will be compiled into \*(UA and may be specified
2971 or, if existing, by their
2973 name, regardless of the actually used terminal control library.
2974 It is however possible to use any capability, as long as the name is
2975 resolvable by the control library or defined in the internal variable
2977 Input sequences are not case-normalized, so that an exact match is
2978 required to update or remove a binding.
2981 .Bd -literal -offset indent
2982 bind base $'\eE',d mle-snarf-word-fwd # Esc(ape)
2983 bind base $'\eE',$'\ec?' mle-snarf-word-bwd # Esc, Delete
2984 bind compose :kf1 ~e
2985 bind base $'\ecA',:khome,w 'echo An editable binding@'
2986 bind base a,b,c rm -rf / @ # Another editable binding
2990 Note that the entire comma-separated list is first parsed (over) as a
2991 shell-token with whitespace as the field separator, before being parsed
2992 and expanded for real with comma as the field separator, therefore
2993 whitespace needs to be properly quoted:
2994 shell-style quoting is documented in the introductional section of
2996 Using Unicode reverse solidus escape sequences renders a binding
2997 defunctional if the locale doesn't support Unicode (see
2998 .Sx "Character sets" ) ,
2999 and using terminal capabilities does so if no terminal control support
3000 is (currently) available.
3003 The following terminal capability names are builtin and can be used in
3005 or (if available) the two-letter
3007 notation regardless of the actually used library.
3008 See the respective manual for a list of capabilities.
3011 can be used to show all the capabilities of
3013 or the given terminal type;
3016 flag will also show supported (non-standard) extensions.
3019 .Bl -tag -compact -width kcuuf_or_kcuuf
3020 .It Cd kbs Ns \0or Cd kb
3022 .It Cd kdch1 Ns \0or Cd kD
3024 .It Cd kDC Ns \0or Cd *4
3025 \(em shifted variant.
3026 .It Cd kel Ns \0or Cd kE
3027 Clear to end of line.
3028 .It Cd kext Ns \0or Cd @9
3030 .It Cd kich1 Ns \0or Cd kI
3032 .It Cd kIC Ns \0or Cd #3
3033 \(em shifted variant.
3034 .It Cd khome Ns \0or Cd kh
3036 .It Cd kHOM Ns \0or Cd #2
3037 \(em shifted variant.
3038 .It Cd kend Ns \0or Cd @7
3040 .It Cd knp Ns \0or Cd kN
3042 .It Cd kpp Ns \0or Cd kP
3044 .It Cd kcub1 Ns \0or Cd kl
3045 Left cursor (with more modifiers: see below).
3046 .It Cd kLFT Ns \0or Cd #4
3047 \(em shifted variant.
3048 .It Cd kcuf1 Ns \0or Cd kr
3049 Right cursor (ditto).
3050 .It Cd kRIT Ns \0or Cd %i
3051 \(em shifted variant.
3052 .It Cd kcud1 Ns \0or Cd kd
3053 Down cursor (ditto).
3055 \(em shifted variant (only terminfo).
3056 .It Cd kcuu1 Ns \0or Cd ku
3059 \(em shifted variant (only terminfo).
3060 .It Cd kf0 Ns \0or Cd k0
3062 Add one for each function key up to
3067 .It Cd kf10 Ns \0or Cd k;
3069 .It Cd kf11 Ns \0or Cd F1
3071 Add one for each function key up to
3079 Some terminals support key-modifier combination extensions, e.g.,
3081 For example, the delete key,
3083 in its shifted variant, the name is mutated to
3085 then a number is appended for the states
3097 .Ql Shift+Alt+Control
3099 The same for the left cursor key,
3101 .Cd KLFT , KLFT3 , KLFT4 , KLFT5 , KLFT6 , KLFT7 , KLFT8 .
3104 Key bindings can be removed with the command
3106 It is advisable to use an initial escape or other control character (e.g.,
3108 for bindings which describe user key combinations (as opposed to purely
3109 terminal capability based ones), in order to avoid ambiguities whether
3110 input belongs to key sequences or not; it also reduces search time.
3113 may help shall keys and sequences be falsely recognized.
3118 Calls a macro that has been created via
3123 (ch) Change the working directory to
3125 or the given argument.
3131 \*(OP Only applicable to S/MIME signed messages.
3132 Takes a message list and a file name and saves the certificates
3133 contained within the message signatures to the named file in both
3134 human-readable and PEM format.
3135 The certificates can later be used to send encrypted messages to the
3136 respective message senders by setting
3137 .Va smime-encrypt-USER@HOST
3142 (ch) Change the working directory to
3144 or the given argument.
3150 Only applicable to threaded mode.
3151 Takes a message list and makes all replies to these messages invisible
3152 in header summaries, unless they are in state
3158 \*(OP\*(NQ Manage colour mappings for the type of colour given as the
3159 (case-insensitive) first argument, which must be one of
3161 for 256-colour terminals,
3166 for the standard 8-colour ANSI / ISO 6429 color palette and
3170 for monochrome terminals.
3171 Monochrome terminals cannot deal with colours, but only (some) font
3175 Without further arguments the list of all currently defined mappings
3176 for the given colour type is shown (as a special case giving
3180 will iterate over all types in order).
3181 Otherwise the second argument defines the mappable slot, the third
3182 argument a (comma-separated list of) colour and font attribute
3183 specification(s), and the optional fourth argument can be used to
3184 specify a precondition: if conditioned mappings exist they are tested in
3185 (creation) order unless a (case-insensitive) match has been found, and
3186 the default mapping (if any has been established) will only be chosen as
3188 The types of precondition available depend on the mappable slot, the
3189 following of which exist:
3192 Mappings prefixed with
3194 are used for the \*(OPal builtin Mailx-Line-Editor (MLE, see
3195 .Sx "On terminal control and line editor" )
3196 and don't support preconditions.
3198 .Bl -tag -compact -width view-partinfo
3200 This mapping is used for the position indicator that is visible when
3201 a line cannot be fully displayed on the screen.
3208 Mappings prefixed with
3210 are used in header summaries, and they all understand the preconditions
3212 (the current message) and
3214 for elder messages (only honoured in conjunction with
3215 .Va datefield-markout-older ) .
3217 .Bl -tag -compact -width view-partinfo
3219 This mapping is used for the
3221 that can be created with the
3225 formats of the variable
3228 For the complete header summary line except the
3230 and the thread structure.
3232 For the thread structure which can be created with the
3234 format of the variable
3239 Mappings prefixed with
3241 are used when displaying messages.
3243 .Bl -tag -compact -width view-partinfo
3245 This mapping is used for so-called
3247 lines, which are MBOX file format specific header lines.
3250 A comma-separated list of headers to which the mapping applies may be
3251 given as a precondition; if the \*(OPal regular expression support is
3252 available then if any of the
3254 (extended) regular expression characters is seen the precondition will
3255 be evaluated as (an extended) one.
3257 For the introductional message info line.
3258 .It Cd view-partinfo
3259 For MIME part info lines.
3263 The following (case-insensitive) colour definitions and font attributes
3264 are understood, multiple of which can be specified in a comma-separated
3274 It is possible (and often applicable) to specify multiple font
3275 attributes for a single mapping.
3278 foreground colour attribute:
3288 To specify a 256-color mode a decimal number colour specification in
3289 the range 0 to 255, inclusive, is supported, and interpreted as follows:
3291 .Bl -tag -compact -width "999 - 999"
3293 the standard ISO 6429 colors, as above.
3295 high intensity variants of the standard colors.
3297 216 colors in tuples of 6.
3299 grayscale from black to white in 24 steps.
3301 .Bd -literal -offset indent
3303 fg() { printf "\e033[38;5;${1}m($1)"; }
3304 bg() { printf "\e033[48;5;${1}m($1)"; }
3306 while [ $i -lt 256 ]; do fg $i; i=$(($i + 1)); done
3307 printf "\e033[0m\en"
3309 while [ $i -lt 256 ]; do bg $i; i=$(($i + 1)); done
3310 printf "\e033[0m\en"
3314 background colour attribute (see
3316 for possible values).
3320 Mappings may be removed with the command
3322 For a generic overview see the section
3323 .Sx "Coloured display" .
3328 (C) Copy messages to files whose names are derived from the author of
3329 the respective message and don't mark them as being saved;
3330 otherwise identical to
3335 (c) Copy messages to the named file and don't mark them as being saved;
3336 otherwise identical to
3341 \*(NQ With no arguments, shows all currently-defined custom headers.
3342 With one argument, shows that custom header.
3343 With more than one argument, creates a new or replaces an existing
3344 custom header with the name given as the first argument, the content of
3345 which being defined by the concatenated remaining arguments.
3347 can be used to delete custom headers.
3348 \*(ID Overwriting of automatically managed headers is neither supported
3350 Defined custom headers will be injected into newly composed or forwarded
3353 .Dl customhdr OpenPGP id=12345678; url=http://www.YYY.ZZ
3357 may also be used to inject custom headers; it is covered by
3362 Show the name of the current working directory.
3366 \*(OP For unencrypted messages this command is identical to
3368 Encrypted messages are first decrypted, if possible, and then copied.
3372 \*(OP For unencrypted messages this command is identical to
3374 Encrypted messages are first decrypted, if possible, and then copied.
3378 Without arguments the current list of macros, including their content,
3379 is shown, otherwise a macro is defined.
3380 A macro definition is a sequence of commands in the following form:
3381 .Bd -literal -offset indent
3390 A defined macro can be invoked explicitly by using the
3394 commands, or implicitly if a macro hook is triggered, e.g., a
3396 Note that interpretation of
3398 depends on how (i.e.,
3400 normal macro, folder hook, hook, account switch) the macro is invoked.
3401 Macros can be deleted via
3405 Macro behaviour, including option localization, will change in v15.
3406 Please be aware of that and possibly embed a version check in a resource
3411 (d) Marks the given message list as
3413 Deleted messages will neither be saved in
3415 nor will they be available for most other commands.
3427 Deletes the current message and displays the next message.
3428 If there is no next message, \*(UA says
3435 up or down by one message when given
3439 argument, respectively.
3443 Takes a message list and marks each given message as a draft.
3444 This mark has no technical meaning in the mail system;
3445 it just causes messages to be marked in the header summary,
3446 and makes them specially addressable.
3450 (ec) Echoes its arguments after applying
3452 expansions and filename transformations, as documented for
3457 (e) Point the text editor (as defined in
3459 at each message from the given list in turn.
3460 Modified contents are discarded unless the
3467 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3468 conditional \(em if the condition of a preceding
3470 was false, check the following condition and execute the following block
3471 if it evaluates true.
3476 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3477 conditional \(em if none of the conditions of the preceding
3481 commands was true, the
3487 (en) Marks the end of an
3488 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3489 conditional execution block.
3494 \*(NQ \*(UA has a strict notion about which variables are
3495 .Sx "INTERNAL VARIABLES"
3496 and which are managed in the program
3498 Since some of the latter are a vivid part of \*(UAs functioning,
3499 however, they are transparently integrated into the normal handling of
3500 internal variables via
3504 To integrate other environment variables of choice into this
3505 transparent handling, and also to export internal variables into the
3506 process environment where they normally are not, a
3508 needs to become established with this command, as in, e.g.,
3511 .Dl environ link PERL5LIB from TZ
3514 Afterwards changing such variables with
3516 will cause automatic updates of the program environment, and therefore
3517 be inherited by newly created child processes.
3518 Sufficient system support provided (it was in BSD as early as 1987, and
3519 is standardized since Y2K) removing such variables with
3521 will remove them also from the program environment, but in any way
3522 the knowledge they ever have been
3525 Note this implies that
3527 may cause loss of links.
3532 will remove an existing link, but leaves the variables as such intact.
3533 Additionally the subcommands
3537 are provided, which work exactly the same as the documented commands
3541 but (additionally) link the variable(s) with the program environment and
3542 thus immediately export them to, or remove them from (if possible),
3543 respectively, the program environment.
3548 \*(OP Since \*(UA uses the console as a user interface it can happen
3549 that messages scroll by too fast to become recognized.
3550 Optionally an error message ring queue is available which stores
3551 duplicates of any error message and notifies the user in interactive
3552 sessions whenever a new error has occurred.
3553 The queue is finite: if its maximum size is reached any new message
3554 replaces the eldest.
3557 can be used to manage this message queue: if given
3559 or no argument the queue will be displayed and cleared,
3561 will only clear all messages from the queue.
3565 (ex or x) Exit from \*(UA without changing the active mailbox and skip
3566 any saving of messages in
3568 as well as a possibly tracked line editor history file.
3574 but open the mailbox readonly.
3578 (fi) The file command switches to a new mailbox.
3579 Without arguments it shows status information of the current mailbox.
3580 If an argument is given, it will write out changes (such as deletions)
3581 the user has made and open a new mailbox.
3582 Some special conventions are recognized for the
3586 .Bl -tag -compact -offset indent -width ".Ar %:__lespec"
3588 (number sign) means the previous file,
3590 (percent sign) means the invoking user's system
3594 means the primary system mailbox of
3596 (and never the value of
3598 regardless of its actual setting),
3600 (ampersand) means the invoking user's
3610 expands to the same value as
3612 but the file is handled as a primary system mailbox by, e.g., the
3616 commands, meaning that messages that have been read in the current
3617 session will be moved to the
3619 mailbox instead of simply being flagged as read.
3622 If the name matches one of the strings defined with the command
3624 it is replaced by its long form and expanded.
3625 If the name ends with
3630 it is treated as being compressed with
3635 respectively, and transparently handled through an intermediate
3636 (un)compression step (using a temporary file) with the according
3637 facility, sufficient support provided.
3638 Likewise, if the named file doesn't exist, but a file with one of the
3639 mentioned compression extensions does, then the name is automatically
3640 expanded and the compressed file is used.
3642 Otherwise, if the name ends with an extension for which
3643 .Va file-hook-load-EXTENSION
3645 .Va file-hook-save-EXTENSION
3646 variables are set, then the given hooks will be used to load and save
3648 and \*(UA will work with an intermediate temporary file.
3650 MBOX files (flat file-based mailboxes) are generally locked during file
3651 operations in order to avoid inconsistencies due to concurrent
3653 \*(OPal Mailbox files which \*(UA treats as system
3655 boxes or primary mailboxes will also be protected by so-called dotlock
3656 files, the traditional way of mail spool file locking: for any file
3660 will be created for the duration of the synchronization \(em
3661 as necessary a privilege-separated dotlock child process will be used
3662 to accommodate for necessary privilege adjustments in order to create
3663 the dotlock file in the same directory
3664 and with the same user and group identities as the file of interest.
3667 for fine-tuning the handling of MBOX files.
3671 refers to a directory with the subdirectories
3676 then it is treated as a folder in
3678 format; \*(ID the variable
3680 can be used to control the format of yet non-existent folders.
3683 .Dl \*(IN protocol://[user[:password]@]host[:port][/path]
3684 .Dl \*(OU protocol://[user@]host[:port][/path]
3686 is taken as an Internet mailbox specification.
3687 The \*(OPally supported protocols are
3691 (POP3 with SSL/TLS encrypted transport).
3694 part is valid only for IMAP; there it defaults to
3696 Also see the section
3697 .Sx "On URL syntax and credential lookup" .
3701 contains special characters, in particular
3705 they must be escaped in URL notation \(en the command
3707 can be used to show the necessary conversion.
3711 Takes a message list and marks the messages as
3713 ged for urgent/special attention.
3714 This mark has no technical meaning in the mail system;
3715 it just causes messages to be highlighted in the header summary,
3716 and makes them specially addressable.
3725 With no arguments, list the names of the folders in the folder directory.
3726 With an existing folder as an argument,
3727 lists the names of folders below the named folder.
3733 but saves the message in a file named after the local part of the first
3734 recipient's address (instead of in
3741 but saves the message in a file named after the local part of the first
3742 recipient's address (instead of in
3749 but responds to all recipients regardless of the
3754 .It Ic followupsender
3757 but responds to the sender only regardless of the
3773 (f) Takes a list of message specifications and displays a summary of
3774 their message headers, exactly as via
3776 An alias of this command is
3779 .Sx "Specifying messages" .
3785 but saves the message in a file named after the local part of the
3786 recipient's address (instead of in
3791 Takes a message and the address of a recipient
3792 and forwards the message to him.
3793 The text of the original message is included in the new one,
3794 with the value of the
3796 variable preceding it.
3801 commands specify which header fields are included in the new message.
3802 Only the first part of a multipart message is included unless the
3803 .Va forward-as-attachment
3807 is set recipient addresses will be stripped from comments, names etc.
3811 Specifies which header fields are to be ignored with the command
3813 This command has no effect when the
3814 .Va forward-as-attachment
3819 Specifies which header fields are to be retained with the command
3824 This command has no effect when the
3825 .Va forward-as-attachment
3830 Define or list command aliases, so-called ghosts.
3831 Without arguments a list of all currently known aliases is shown.
3832 With one argument the expansion of the given alias is shown.
3833 With two or more arguments a command alias is defined or updated: the
3834 first argument is the name under which the remaining command line should
3835 be accessible, the content of which can be just about anything.
3836 A ghost can be used everywhere a normal command can be used, but always
3837 takes precedence; any arguments that are given to the command alias are
3838 joined onto the alias content, and the resulting string forms the
3839 command line that is, in effect, executed.
3842 .Bd -literal -offset indent
3844 `ghost': no such alias: "xx"
3847 ghost xx "echo hello,"
3856 (h) Show the current group of headers, the size of which depends on
3859 and the style of which can be adjusted with the variable
3861 If a message-specification is given the group of headers containing the
3862 first message therein is shown and the message at the top of the screen
3877 the list of history entries;
3880 argument selects and shows the respective history entry \(en
3883 to accept it, and the history entry will become the new history top.
3884 The default mode if no arguments are given is
3891 Takes a message list and marks each message therein to be saved in the
3896 Does not override the
3899 \*(UA deviates from the POSIX standard with this command, because a
3901 command issued after
3903 will display the following message, not the current one.
3908 (i) Part of the nestable
3909 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3910 conditional execution construct \(em if the given condition is true then
3911 the encapsulated block is executed.
3912 POSIX only supports the (case-insensitive) conditions
3917 end, all remaining conditions are non-portable extensions; note that
3918 falsely specified conditions cause the execution of the entire
3919 conditional construct until the (matching) closing
3921 command to be suppressed.
3922 The syntax of the nestable
3924 conditional execution construct requires that each condition and syntax
3925 element is surrounded by whitespace.
3927 .Bd -literal -offset indent
3936 The (case-insensitive) condition
3938 erminal will evaluate to true if the standard input is a terminal, i.e.,
3939 in interactive sessions.
3940 Another condition can be any boolean value (see the section
3941 .Sx "INTERNAL VARIABLES"
3942 for textual boolean representations) to mark an enwrapped block as
3945 .Dq always execute .
3946 It is possible to check
3947 .Sx "INTERNAL VARIABLES"
3950 variables for existence or compare their expansion against a user given
3951 value or another variable by using the
3953 .Pf ( Dq variable next )
3954 conditional trigger character;
3955 a variable on the right hand side may be signalled using the same
3957 The variable names may be enclosed in a pair of matching braces.
3960 The available comparison operators are
3964 (less than or equal to),
3970 (greater than or equal to),
3974 (is substring of) and
3976 (is not substring of).
3977 The values of the left and right hand side are treated as strings and
3978 are compared 8-bit byte-wise, ignoring case according to the rules of
3979 the US-ASCII encoding (therefore, dependent on the active locale,
3980 possibly producing false results for strings in the locale encoding).
3981 Except for the substring checks the comparison will instead be performed
3982 arithmetically if both, the user given value as well as the variable
3983 content, can be parsed as numbers (integers).
3984 An unset variable is treated as the empty string.
3987 When the \*(OPal regular expression support is available, the additional
3993 They treat the right hand side as an extended regular expression that is
3994 matched case-insensitively and according to the active
3996 locale, meaning that strings in the locale encoding should be matched
4000 Conditions can be joined via AND-OR lists (where the AND operator is
4002 and the OR operator is
4004 which have equal precedence and will be evaluated with left
4005 associativity, thus using the same syntax that is known for the
4007 It is also possible to form groups of conditions and lists by enclosing
4008 them in pairs of brackets
4009 .Ql [\ \&.\&.\&.\ ] ,
4010 which may be interlocked within each other, and also be joined via
4014 The results of individual conditions and entire groups may be modified
4015 via unary operators: the unary operator
4017 will reverse the result.
4019 .Bd -literal -offset indent
4023 if $ttycharset == "UTF-8"
4024 echo *ttycharset* is set to UTF-8, case-insensitively
4028 echo These two variables are equal
4030 if $version-major >= 15
4031 echo Running a new version..
4032 if $features =@ +regex
4033 if $TERM =~ "^xterm\&.*"
4034 echo ..in an X terminal
4037 if [ [ true ] && [ [ ${debug} ] || [ $verbose ] ] ]
4040 if true && $debug || ${verbose}
4041 echo Left associativity, as is known from the shell
4043 if ! ! true && ! [ ! $debug && ! $verbose ]
4044 echo Unary operator support
4052 Without arguments the list of ignored header fields is shown,
4053 otherwise the given list of header fields is added to the ignore list:
4054 Header fields in the ignore list are not shown on the terminal when
4055 a message is displayed.
4056 To display a message in its entirety, use the commands
4067 Shows the names of all available commands, alphabetically sorted.
4068 If given any non-whitespace argument the list will be shown in the order
4069 in which command prefixes are searched.
4072 output is available.
4076 This command can be used to localize changes to variables, meaning that
4077 their state will be reverted to the former one once the covered scope
4079 It can only be used inside of macro definition blocks introduced by
4083 and is interpreted as a boolean (string, see
4084 .Sx "INTERNAL VARIABLES" ) ;
4087 of an account is left once it is switched off again.
4088 .Bd -literal -offset indent
4089 define temporary_settings {
4104 enables change localization and calls
4106 which explicitly resets localization, then any value changes within
4108 will still be reverted by
4110 \*(ID Once the outermost level, the one which enabled localization
4111 first, is left, but no earlier, all adjustments will be unrolled.
4112 \*(ID Likewise worth knowing, if in this example
4114 changes to a different
4116 which sets some variables that are yet covered by localizations, their
4117 scope will be extended, and in fact leaving the
4119 will (thus) restore settings in (likely) global scope which actually
4120 were defined in a local, private context.
4124 Reply to messages that come in via known
4127 .Pf ( Ic mlsubscribe )
4128 mailing lists, or pretend to do so (see
4129 .Sx "Mailing lists" ) :
4132 functionality this will actively resort and even remove message
4133 recipients in order to generate a message that is supposed to be sent to
4135 For example it will also implicitly generate a
4136 .Ql Mail-Followup-To:
4137 header if that seems useful, regardless of the setting of the variable
4144 but saves the message in a file named after the local part of the first
4145 recipient's address (instead of in
4150 (m) Takes a (list of) recipient address(es) as (an) argument(s),
4151 or asks on standard input if none were given;
4152 then collects the remaining mail content and sends it out.
4156 (mb) The given message list is to be sent to
4158 when \*(UA is quit; this is the default action unless the
4161 \*(ID This command can only be used in a primary system mailbox (see
4166 Without any arguments the content of the MIME type cache will displayed.
4167 Otherwise each argument defines a complete MIME type specification of
4168 a type that shall be added (prepended) to the cache.
4169 In any event MIME type sources are loaded first as necessary \(en
4170 .Va mimetypes-load-control
4171 can be used to fine-tune which sources are actually loaded.
4172 Refer to the section on
4173 .Sx "The mime.types files"
4174 for more on MIME type specifications and this topic in general.
4175 MIME type unregistration and cache resets can be triggered with
4180 Without arguments the list of all currently defined mailing lists
4181 (and their attributes, if any) is shown; a more verbose listing will be
4182 produced if either of
4187 Otherwise all given arguments (which need not be quoted except for
4188 whitespace) will be added and henceforth be recognized as mailing lists.
4189 Mailing lists may be removed via the command
4192 If the \*(OPal regular expression support is available then mailing
4193 lists may also be specified as (extended) regular expressions (see
4199 Without arguments the list of all currently defined mailing lists which
4200 have a subscription attribute is shown; a more verbose listing will be
4201 produced if either of
4206 Otherwise this attribute will be set for all given mailing lists,
4207 newly creating them as necessary (as via
4209 Subscription attributes may be removed via the command
4218 but moves the messages to a file named after the local part of the
4219 sender address of the first message (instead of in
4226 but marks the messages for deletion if they were transferred
4233 but also displays ignored header fields and all MIME parts.
4241 on the given messages, even in non-interactive mode and as long as the
4242 standard output is a terminal.
4248 \*(OP When used without arguments or if
4250 has been given the content of the
4252 cache is shown, loading it first as necessary.
4255 then the cache will only be initialized and
4257 will remove its contents.
4258 Note that \*(UA will try to load the file only once, use
4259 .Ql Ic \&\&netrc Ns \:\0\:clear
4260 to unlock further attempts.
4265 .Sx "On URL syntax and credential lookup" ;
4267 .Sx "The .netrc file"
4268 documents the file format in detail.
4272 Checks for new mail in the current folder without committing any changes
4274 If new mail is present, a message is shown.
4278 the headers of each new message are also shown.
4279 This command is not available for all mailbox types.
4287 Goes to the next message in sequence and types it.
4288 With an argument list, types the next matching message.
4302 If the current folder is accessed via a network connection, a
4304 command is sent, otherwise no operation is performed.
4310 but also displays ignored header fields and all MIME parts.
4318 on the given messages, even in non-interactive mode and as long as the
4319 standard output is a terminal.
4327 but also pipes ignored header fields and all parts of MIME
4328 .Ql multipart/alternative
4333 (pi) Takes a message list and a shell command
4334 and pipes the messages through the command.
4335 Without an argument the current message is piped through the command
4342 every message is followed by a formfeed character.
4363 (q) Terminates the session, saving all undeleted, unsaved messages in
4366 preserving all messages marked with
4370 or never referenced in the system
4372 box, and removing all other messages from the primary system mailbox.
4373 If new mail has arrived during the session,
4375 .Dq You have new mail
4377 If given while editing a mailbox file with the command line flag
4379 then the edit file is rewritten.
4380 A return to the shell is effected,
4381 unless the rewrite of edit file fails,
4382 in which case the user can escape with the exit command.
4396 Removes the named files or directories.
4397 If a name refer to a mailbox, e.g., a Maildir mailbox, then a mailbox
4398 type specific removal will be performed, deleting the complete mailbox.
4399 The user is asked for confirmation in interactive mode.
4403 Takes the name of an existing folder
4404 and the name for the new folder
4405 and renames the first to the second one.
4406 Both folders must be of the same type.
4410 (R) Reply to originator.
4411 Does not reply to other recipients of the original message.
4413 will exchange this command with
4417 is set the recipient address will be stripped from comments, names etc.
4421 (r) Take a message and group-responds to it by addressing the sender
4424 .Va followup-to-honour ,
4427 .Va recipients-in-cc
4428 influence response behaviour.
4431 offers special support for replying to mailing lists.
4434 is set recipient addresses will be stripped from comments, names etc.
4447 but initiates a group-reply regardless of the value of
4454 but responds to the sender only regardless of the value of
4461 but does not add any header lines.
4462 This is not a way to hide the sender's identity,
4463 but useful for sending a message again to the same recipients.
4467 Takes a list of messages and a user name
4468 and sends each message to the named user.
4470 and related header fields are prepended to the new copy of the message.
4488 .It Ic respondsender
4494 (ret) Without arguments the list of retained header fields is shown,
4495 otherwise the given list of header fields is added to the retain list:
4496 Header fields in the retain list are shown on the terminal when
4497 a message is displayed, all other header fields are suppressed.
4498 To display a message in its entirety, use the commands
4507 takes precedence over the mentioned.
4513 but saves the messages in a file named after the local part of the
4514 sender of the first message instead of (in
4516 and) taking a filename argument.
4520 (s) Takes a message list and a filename and appends each message in turn
4521 to the end of the file.
4522 If no filename is given, the
4525 The filename in quotes, followed by the generated character count
4526 is echoed on the user's terminal.
4527 If editing a primary system mailbox the messages are marked for deletion.
4528 Filename interpretation as described for the
4530 command is performed.
4547 Header fields thus marked are filtered out when saving a message by
4549 or when automatically saving to
4551 This command should only be applied to header fields that do not contain
4552 information needed to decode the message,
4553 as MIME content fields do.
4565 Header fields thus marked are the only ones saved with a message when
4568 or when automatically saving to
4573 The use of this command is strongly discouraged since it may strip
4574 header fields that are needed to decode the message correctly.
4578 Takes a message specification (list) and displays a header summary of
4579 all matching messages, as via
4581 This command is an alias of
4584 .Sx "Specifying messages" .
4588 Takes a message list and marks all messages as having been read.
4592 (se) Without arguments this command shows all internal variables which
4593 are currently known to \*(UA (they have been set).
4594 A more verbose listing will be produced if either of
4598 are set, in which case variables may be preceded with a comment line
4599 that gives some context of what \*(UA knows about the given variable.
4601 Otherwise the given variables (and arguments) are set or adjusted.
4602 Arguments are of the form
4604 (no space before or after
4608 if there is no value, i.e., a boolean variable.
4609 Quotation marks may be placed around any part of the assignment
4610 statement to quote blanks or tabs, e.g.,
4612 .Dl set indentprefix='->'
4614 If an argument begins with
4618 the effect is the same as invoking the
4620 command with the remaining part of the variable
4621 .Pf ( Ql unset save ) .
4625 that is known to map to an environment variable will automatically cause
4626 updates in the program environment (unsetting a variable in the
4627 environment requires corresponding system support).
4628 Please use the command
4630 for further environmental control.
4635 .Sx "INTERNAL VARIABLES"
4641 (sh) Invokes an interactive version of the shell.
4645 Without arguments the list of all currently defined shortcuts is
4647 Otherwise all given arguments (which need not be quoted except for
4648 whitespace) are treated as pairs of shortcuts and their expansions,
4649 creating new or changing already existing shortcuts, as necessary.
4650 Shortcuts may be removed via the command
4652 The expansion strings should be in the syntax that has been described
4661 but performs neither MIME decoding nor decryption, so that the raw
4662 message text is shown.
4666 (si) Shows the size in characters of each message of the given
4671 Shows the current sorting criterion when used without an argument.
4672 Otherwise creates a sorted representation of the current folder,
4675 command and the addressing modes such that they refer to messages in
4677 Message numbers are the same as in regular mode.
4681 a header summary in the new order is also displayed.
4682 Automatic folder sorting can be enabled by setting the
4684 variable, as in, e.g.,
4685 .Ql set autosort=thread .
4686 Possible sorting criterions are:
4688 .Bl -tag -compact -offset indent -width "subject"
4690 Sort the messages by their
4692 field, that is by the time they were sent.
4694 Sort messages by the value of their
4696 field, that is by the address of the sender.
4699 variable is set, the sender's real name (if any) is used.
4701 Sort the messages by their size.
4703 \*(OP Sort the message by their spam score, as has been classified by
4706 Sort the messages by their message status.
4708 Sort the messages by their subject.
4710 Create a threaded display.
4712 Sort messages by the value of their
4714 field, that is by the address of the recipient.
4717 variable is set, the recipient's real name (if any) is used.
4722 (so) The source command reads commands from the given file, which is
4723 subject to the usual filename expansions (see introductional words of
4725 If the given argument ends with a vertical bar
4727 then the argument will instead be interpreted as a shell command and
4728 \*(UA will read the output generated by it.
4731 cannot be used from within macros that execute as
4732 .Va folder-hook Ns s
4735 i.e., it can only be called from macros that were
4742 (beside not supporting pipe syntax aka shell command input) is that
4743 this command will not generate an error if the given file argument
4744 cannot be opened successfully.
4745 This can matter in, e.g., resource files, since loading of those is
4746 stopped when an error is encountered.
4750 \*(OP Takes a list of messages and clears their
4756 \*(OP Takes a list of messages and causes the
4758 to forget it has ever used them to train its Bayesian filter.
4759 Unless otherwise noted the
4761 flag of the message is inspected to chose whether a message shall be
4769 \*(OP Takes a list of messages and informs the Bayesian filter of the
4773 This also clears the
4775 flag of the messages in question.
4779 \*(OP Takes a list of messages and rates them using the configured
4780 .Va spam-interface ,
4781 without modifying the messages, but setting their
4783 flag as appropriate; because the spam rating headers are lost the rate
4784 will be forgotten once the mailbox is left.
4785 Refer to the manual section
4787 for the complete picture of spam handling in \*(UA.
4791 \*(OP Takes a list of messages and sets their
4797 \*(OP Takes a list of messages and informs the Bayesian filter of the
4803 flag of the messages in question.
4812 Create a threaded representation of the current folder,
4813 i.\|e. indent messages that are replies to other messages in the header
4814 display and change the
4816 command and the addressing modes such that they refer to messages in the
4818 Message numbers are the same as in unthreaded mode.
4822 a header summary in threaded order is also displayed.
4836 (to) Takes a message list and types out the first
4838 lines of each message on the users' terminal.
4839 The only header fields that are displayed are
4846 will instead honour configured lists).
4847 It is possible to apply compression to what is displayed by setting
4849 Messages are decrypted and converted to the terminal character set
4854 (tou) Takes a message list and marks the messages for saving in
4856 \*(UA deviates from the POSIX standard with this command,
4859 command will display the following message instead of the current one.
4865 but also displays out ignored header fields and all parts of MIME
4866 .Ql multipart/alternative
4871 (t) Takes a message list and types out each message on the users'
4877 For MIME multipart messages, all parts with a content type of
4881 are shown, the other are hidden except for their headers.
4882 Messages are decrypted and converted to the terminal character set
4887 Delete all given accounts.
4888 An error message is shown if a given account is not defined.
4891 will discard all existing accounts.
4895 (una) Takes a list of names defined by alias commands
4896 and discards the remembered groups of users.
4899 will discard all existing aliases.
4903 Takes a message list and marks each message as not having been answered.
4909 ing, specified by its context and input sequence, both of which may be
4910 specified as a wildcard (asterisk,
4914 will remove all bindings of all contexts.
4918 Only applicable to threaded mode.
4919 Takes a message list and makes the message and all replies to it visible
4920 in header summaries again.
4921 When a message becomes the current message,
4922 it is automatically made visible.
4923 Also when a message with collapsed replies is displayed,
4924 all of these are automatically uncollapsed.
4930 mapping for the given colour type (see
4932 for a list of types) and mapping; if the optional precondition argument
4933 is used then only the exact tuple of mapping and precondition is removed.
4936 will remove all mappings (no precondition allowed).
4938 .Sx "Coloured display"
4939 for the general picture.
4943 Deletes the custom headers given as arguments.
4946 will remove all custom headers.
4950 Undefine all given macros.
4951 An error message is shown if a given macro is not defined.
4954 will discard all existing macros.
4958 (u) Takes a message list and marks each message as not being deleted.
4962 Takes a message list and
4968 Takes a message list and marks each message as not being
4973 Removes the header field names from the list of ignored fields for the
4978 will remove all fields.
4982 Removes the header field names from the list of retained fields for the
4987 will remove all fields.
4991 Remove all the given command
4995 will remove all ghosts.
4999 Removes the header field names from the list of ignored fields.
5002 will remove all fields.
5006 Delete all given MIME types, e.g.,
5007 .Ql unmimetype text/plain
5008 will remove all registered specifications for the MIME type
5012 will discard all existing MIME types, just as will
5014 but which also reenables cache initialization via
5015 .Va mimetypes-load-control .
5019 Forget about all the given mailing lists.
5022 will remove all lists.
5027 .It Ic unmlsubscribe
5028 Remove the subscription attribute from all given mailing lists.
5031 will clear the attribute from all lists which have it set.
5042 Takes a message list and marks each message as not having been read.
5046 Removes the header field names from the list of retained fields.
5049 will remove all fields.
5053 Removes the header field names from the list of ignored fields for
5057 will remove all fields.
5061 Removes the header field names from the list of retained fields for
5065 will remove all fields.
5069 (uns) Takes a list of internal variable names and discards their
5070 remembered values; the reverse of
5077 Deletes the shortcut names given as arguments.
5080 will remove all shortcuts.
5084 Disable sorted or threaded mode
5090 return to normal message order and,
5094 displays a header summary.
5104 Decode the given URL-encoded string arguments and show the results.
5105 Note the resulting strings may not be valid in the current locale, see
5110 URL-encode the given arguments and show the results.
5111 Because the arguments effectively are in the character set of the
5112 current locale the results will vary accordingly unless the input solely
5113 consists of characters in the portable character set, see
5114 .Sx "Character sets" .
5118 Edit the values of or create the given variable(s) in the
5120 Boolean variables cannot be edited.
5124 This command produces the same output as the listing mode of
5128 ity adjustments, but only for the given variables.
5132 \*(OP Takes a message list and verifies each message.
5133 If a message is not a S/MIME signed message,
5134 verification will fail for it.
5135 The verification process checks if the message was signed using a valid
5137 if the message sender's email address matches one of those contained
5138 within the certificate,
5139 and if the message content has been altered.
5143 Shows the version and feature set of \*(UA.
5147 (v) Takes a message list and invokes the display editor on each message.
5148 Modified contents are discarded unless the
5154 (w) For conventional messages the body without all headers is written.
5155 The output is decrypted and converted to its native format as necessary.
5156 If the output file exists, the text is appended.
5157 If a message is in MIME multipart format its first part is written to
5158 the specified file as for conventional messages,
5159 and the user is asked for a filename to save each other part.
5160 For convience saving of each part may be skipped by giving an empty value;
5161 the same result can also be achieved by writing it to
5163 For the second and subsequent parts a leading
5165 character causes the part to be piped to the remainder of the user input
5166 interpreted as a shell command;
5167 otherwise the user input is expanded as usually for folders,
5168 e.g., tilde expansion is performed.
5169 In non-interactive mode, only the parts of the multipart message
5170 that have a filename given in the part header are written,
5171 the others are discarded.
5172 The original message is never marked for deletion in the originating
5175 the contents of the destination file are overwritten if the file
5177 No special handling of compressed files is performed.
5186 \*(UA presents message headers in windowfuls as described under the
5189 This command scrolls to the next window of messages.
5190 If an argument is given, it specifies the window to use.
5191 A number prefixed by
5195 indicates that the window is calculated in relation to the current position.
5196 A number without a prefix specifies an absolute window number,
5199 lets \*(UA scroll to the last window of messages.
5205 but scrolls to the next or previous window that contains at least one
5214 .\" .Sh TILDE ESCAPES {{{
5217 Here is a summary of the tilde escapes,
5218 which are used to perform special functions when composing messages.
5219 Tilde escapes are only recognized at the beginning of lines.
5222 is somewhat of a misnomer since the actual escape character can be
5223 changed by adjusting the option
5226 .Bl -tag -width ".Ic __ filename"
5229 Insert the string of text in the message prefaced by a single
5231 (If the escape character has been changed,
5232 that character must be doubled
5233 in order to send it at the beginning of a line.)
5236 .It Ic ~! Ar command
5237 Execute the indicated shell
5239 then return to the message.
5243 Same effect as typing the end-of-file character.
5246 .It Ic ~: Ar \*(UA-command Ns \0or Ic ~_ Ar \*(UA-command
5247 Execute the given \*(UA command.
5248 Not all commands, however, are allowed.
5252 Write a summary of command escapes.
5255 .It Ic ~< Ar filename
5260 .It Ic ~<! Ar command
5262 is executed using the shell.
5263 Its standard output is inserted into the message.
5266 .It Ic ~@ Op Ar filename...
5267 With no arguments, edit the attachment list interactively.
5268 If an attachment's file name is left empty,
5269 that attachment is deleted from the list.
5270 When the end of the attachment list is reached,
5271 \*(UA will ask for further attachments until an empty name is given.
5272 If a given file name solely consists of the number sign
5274 followed by a valid message number of the currently active mailbox, then
5275 the given message is attached as a MIME
5277 and the rest of this section does not apply.
5279 If character set conversion has been compiled into \*(UA, then this mode
5280 gives the user the option to specify input and output character sets,
5281 unless the file extension indicates binary content, in which case \*(UA
5282 asks whether this step shall be skipped for the attachment in question.
5283 If not skipped, then the charset that succeeds to represent the
5284 attachment data will be used in the
5286 MIME parameter of the mail message:
5288 .Bl -bullet -compact
5290 If input and output character sets are specified, then the conversion is
5291 performed on the fly.
5292 The user will be asked repeatedly until the desired conversion succeeds.
5294 If only an output character set is specified, then the input is assumed
5297 charset and will be converted to the given output charset on the fly.
5298 The user will be asked repeatedly until the desired conversion succeeds.
5300 If no character sets are specified at all then the algorithm that is
5301 documented in the section
5302 .Sx "Character sets"
5303 is applied, but directly and on the fly.
5304 The user will be asked repeatedly until the desired conversion succeeds.
5306 Finally, if an input-, but no output character set is specified, then no
5307 conversion is ever performed, but the
5309 MIME parameter value will still be set to the user input.
5311 The character set selection loop can be left by typing
5313 i.e., causing an interrupt.
5314 .\" \*(OU next sentence
5315 Note that before \*(UA version 15.0 this terminates the entire
5316 current attachment selection, not only the character set selection.
5319 Without character set conversion support, \*(UA will ask for the input
5320 character set only, and it'll set the
5322 MIME parameter value to the given input, if any;
5323 if no user input is seen then the
5325 character set will be used for the parameter value instead.
5326 Note that the file extension check isn't performed in this mode, since
5327 no conversion will take place anyway.
5329 Note that in non-interactive mode, for reproduceabilities sake, there
5330 will always be two questions for each attachment, regardless of whether
5331 character set conversion is available and what the file extension is.
5332 The first asks for the filename, and the second asks for the input
5333 character set to be passed through to the corresponding MIME parameter;
5334 no conversion will be tried if there is input to the latter question,
5335 otherwise the usual conversion algorithm, as above, is applied.
5336 For message attachments, the answer to the second question is completely
5341 arguments are specified for the
5343 command they are treated as a file list of
5345 -style quoted arguments, optionally also separated by commas, which are
5346 expanded and then appended to the existing list of message attachments.
5347 Message attachments can only be added via the first method.
5348 In this mode the (text) attachments are assumed to be in
5350 encoding, and will be evaluated as documented in the section
5351 .Sx "Character sets" .
5355 Inserts the string contained in the
5358 .Ql Ic ~i Ns \0Sign ) .
5359 The escape sequences tabulator
5367 Inserts the string contained in the
5370 .Ql Ic ~i Ns \0sign ) .
5371 The escape sequences tabulator
5378 .It Ic ~b Ar name ...
5379 Add the given names to the list of blind carbon copy recipients.
5382 .It Ic ~c Ar name ...
5383 Add the given names to the list of carbon copy recipients.
5387 Read the file specified by the
5389 variable into the message.
5393 Invoke the text editor on the message collected so far.
5394 After the editing session is finished,
5395 the user may continue appending text to the message.
5398 .It Ic ~F Ar messages
5399 Read the named messages into the message being sent, including all
5400 message headers and MIME parts.
5401 If no messages are specified, read in the current message.
5404 .It Ic ~f Ar messages
5405 Read the named messages into the message being sent.
5406 If no messages are specified, read in the current message.
5410 lists are used to modify the message headers.
5411 For MIME multipart messages,
5412 only the first displayable part is included.
5416 Edit the message header fields
5421 by typing each one in turn and allowing the user to edit the field.
5422 The default values for these fields originate from the
5430 Edit the message header fields
5436 by typing each one in turn and allowing the user to edit the field.
5439 .It Ic ~i Ar variable
5440 Insert the value of the specified variable into the message,
5441 adding a newline character at the end.
5442 The message remains unaltered if the variable is unset or empty.
5443 The escape sequences tabulator
5450 .It Ic ~M Ar messages
5451 Read the named messages into the message being sent,
5454 If no messages are specified, read the current message.
5457 .It Ic ~m Ar messages
5458 Read the named messages into the message being sent,
5461 If no messages are specified, read the current message.
5465 lists are used to modify the message headers.
5466 For MIME multipart messages,
5467 only the first displayable part is included.
5471 Display the message collected so far,
5472 prefaced by the message header fields
5473 and followed by the attachment list, if any.
5477 Abort the message being sent,
5478 copying it to the file specified by the
5485 .It Ic ~R Ar filename
5486 Read the named file into the message, indented by
5490 .It Ic ~r Ar filename
5491 Read the named file into the message.
5495 Cause the named string to become the current subject field.
5498 .It Ic ~t Ar name ...
5499 Add the given name(s) to the direct recipient list.
5502 .It Ic ~U Ar messages
5503 Read in the given / current message(s) excluding all headers, indented by
5507 .It Ic ~u Ar messages
5508 Read in the given / current message(s), excluding all headers.
5512 Invoke an alternate editor (defined by the
5514 option) on the message collected so far.
5515 Usually, the alternate editor will be a screen editor.
5516 After the editor is quit,
5517 the user may resume appending text to the end of the message.
5520 .It Ic ~w Ar filename
5521 Write the message onto the named file.
5523 the message is appended to it.
5529 except that the message is not saved at all.
5532 .It Ic ~| Ar command
5533 Pipe the message through the specified filter command.
5534 If the command gives no output or terminates abnormally,
5535 retain the original text of the message.
5538 is often used as a rejustifying filter.
5543 .\" .Sh INTERNAL VARIABLES {{{
5544 .Sh "INTERNAL VARIABLES"
5546 Internal \*(UA variables are controlled via the
5550 commands; prefixing a variable name with the string
5554 has the same effect as using
5560 Creation or editing of variables can be performed in the
5565 will give more insight on the given variable(s), and
5567 when called without arguments, will show a listing of all variables.
5568 Some well-known variables will also become inherited from the
5571 implicitly, others can be explicitly imported with the command
5573 and henceforth share the said properties.
5576 Two different kind of internal variables exist.
5577 There are boolean variables, which can only be in one of the two states
5581 and value variables with a(n optional) string value.
5582 For the latter proper quoting is necessary upon assignment time, the
5583 introduction of the section
5585 documents the supported quoting rules.
5587 .Bd -literal -offset indent
5588 wysh set one=val\e 1 two="val 2" \e
5589 three='val "3"' four=$'val \e'4\e''
5590 varshow one two three four
5591 unset one two three four
5595 Dependent upon the actual option the string values will be interpreted
5596 as numbers, colour names, normal text etc., but there also exists
5597 a special kind of string value, the
5598 .Dq boolean string ,
5599 which must either be a decimal integer (in which case
5603 and any other value is true) or any of the (case-insensitive) strings
5609 for a false boolean and
5615 for a true boolean; a special kind of boolean string is the
5617 which is a boolean string that can optionally be prefixed with the
5618 (case-insensitive) term
5622 which causes prompting of the user in interactive mode, with the given
5623 boolean as the default value.
5625 .\" .Ss "Initial settings" {{{
5626 .\" (Keep in SYNC: ./nail.h:okeys, ./nail.rc, ./nail.1:"Initial settings")
5627 .Ss "Initial Settings"
5629 The standard POSIX 2008/Cor 1-2013 mandates the following initial
5635 .Pf no Va autoprint ,
5649 .Pf no Va ignoreeof ,
5651 .Pf no Va keepsave ,
5653 .Pf no Va outfolder ,
5658 (note that \*(UA deviates from the standard by using
5662 special prompt escape results in
5670 .Pf no Va sendwait ,
5679 Notes: \*(UA doesn't support the
5681 variable \(en use command line options or
5683 to pass options through to a
5685 And the default global
5687 file (which is loaded unless the
5689 command line flag has been used or the
5690 .Ev NAIL_NO_SYSTEM_RC
5691 environment variable is set) bends those initial settings a bit, e.g.,
5692 it sets the variables
5697 to name a few, calls
5699 etc., and should thus be taken into account.
5702 .\" .Ss "Variables" {{{
5705 .Bl -tag -width ".It Va _utoprin_"
5707 .It Va add-file-recipients
5708 \*(BO When file or pipe recipients have been specified,
5709 mention them in the corresponding address fields of the message instead
5710 of silently stripping them from their recipient list.
5711 By default such addressees are not mentioned.
5715 \*(BO Causes only the local part to be evaluated
5716 when comparing addresses.
5720 \*(BO Causes messages saved in
5722 to be appended to the end rather than prepended.
5723 This should always be set.
5727 \*(BO Causes \*(UA to prompt for the subject of each message sent.
5728 If the user responds with simply a newline,
5729 no subject field will be sent.
5733 \*(BO Causes the prompts for
5737 lists to appear after the message has been edited.
5741 \*(BO If set, \*(UA asks for files to attach at the end of each message,
5742 shall the list be found empty at that time.
5743 An empty line finalizes the list.
5747 \*(BO Causes the user to be prompted for carbon copy recipients
5748 (at the end of each message if
5752 are set) shall the list be found empty (at that time).
5753 An empty line finalizes the list.
5757 \*(BO Causes the user to be prompted for blind carbon copy
5758 recipients (at the end of each message if
5762 are set) shall the list be found empty (at that time).
5763 An empty line finalizes the list.
5767 \*(BO\*(OP Causes the user to be prompted if the message is to be
5768 signed at the end of each message.
5771 variable is ignored when this variable is set.
5775 \*(BO Alternative name for
5782 .It Va attachment-ask-content-description , \
5783 attachment-ask-content-disposition , \
5784 attachment-ask-content-id , \
5785 attachment-ask-content-type
5786 \*(BO If set then the user will be prompted for some attachment
5787 information when editing the attachment list.
5788 It is advisable to not use these but for the first of the variables;
5789 even for that it has to be noted that the data is used
5795 A sequence of characters to display in the
5799 as shown in the display of
5801 each for one type of messages (see
5802 .Sx "Message states" ) ,
5803 with the default being
5806 .Ql NU\ \ *HMFAT+\-$~
5809 variable is set, in the following order:
5811 .Bl -tag -compact -offset indent -width ".It Ql _"
5833 start of a collapsed thread.
5835 an uncollapsed thread (TODO ignored for now).
5839 classified as possible spam.
5845 Specifies a list of recipients to which a blind carbon copy of each
5846 outgoing message will be sent automatically.
5850 Specifies a list of recipients to which a carbon copy of each outgoing
5851 message will be sent automatically.
5855 \*(BO Causes threads to be collapsed automatically when threaded mode
5862 \*(BO Causes the delete command to behave like
5864 thus, after deleting a message the next one will be typed automatically.
5868 \*(BO\*(OB Causes threaded mode (see the
5870 command) to be entered automatically when a folder is opened.
5872 .Ql autosort=thread .
5876 Causes sorted mode (see the
5878 command) to be entered automatically with the value of this option as
5879 sorting method when a folder is opened, e.g.,
5880 .Ql set autosort=thread .
5884 \*(BO Enables the substitution of
5886 by the contents of the last command line in shell escapes.
5889 .It Va batch-exit-on-error
5890 \*(BO If the batch mode has been enabled via the
5892 command line option, then this variable will be consulted whenever \*(UA
5893 completes one operation (returns to the command prompt); if it is set
5894 then \*(UA will terminate if the last operation generated an error.
5898 \*(OP Terminals generate multi-byte sequences for certain forms of
5899 input, for example for function and other special keys.
5900 Some terminals however do not write these multi-byte sequences as
5901 a whole, but byte-by-byte, and the latter is what \*(UA actually reads.
5902 This variable specifies the timeout in milliseconds that the MLE (see
5903 .Sx "On terminal control and line editor" )
5904 waits for more bytes to arrive unless it considers a sequence
5910 \*(BO Causes automatic display of a header summary after executing a
5912 command, and thus complements the standard variable
5914 which controls header summary display on program startup.
5915 It is only meaningful if
5921 \*(BO Sets some cosmetical features to traditional BSD style;
5922 has the same affect as setting
5924 and all other variables prefixed with
5926 it also changes the meaning of the \*(UA specific
5929 escape sequence and changes behaviour of
5931 (which doesn't exist in BSD).
5935 \*(BO Changes the letters shown in the first column of a header
5936 summary to traditional BSD style.
5940 \*(BO Changes the display of columns in a header summary to traditional
5945 \*(BO Changes some informational messages to traditional BSD style.
5951 field to appear immediately after the
5953 field in message headers and with the
5955 .Sx "TILDE ESCAPES" .
5959 The value that should appear in the
5963 MIME header fields when no character set conversion of the message data
5965 This defaults to US-ASCII, and the chosen character set should be
5966 US-ASCII compatible.
5970 \*(OP The default 8-bit character set that is used as an implicit last
5971 member of the variable
5973 This defaults to UTF-8.
5974 If no character set conversion capabilities are available in \*(UA then
5975 the only supported character set is
5977 Refer to the section
5978 .Sx "Character sets"
5979 for the complete picture of character set conversion in \*(UA.
5982 .It Va charset-unknown-8bit
5983 \*(OP RFC 1428 specifies conditions when internet mail gateways shall
5985 the content of a mail message by using a character set with the name
5987 Because of the unclassified nature of this character set \*(UA will not
5988 be capable to convert this character set to any other character set.
5989 If this variable is set any message part which uses the character set
5991 is assumed to really be in the character set given in the value,
5992 otherwise the (final) value of
5994 is used for this purpose.
5996 This variable will also be taken into account if a MIME type (see
5997 .Sx "The mime.types files" )
5998 of a MIME message part that uses the
6000 character set is forcefully treated as text.
6004 The default value for the
6009 .It Va colour-disable
6010 \*(BO\*(OP Forcefully disable usage of colours.
6011 Also see the section
6012 .Sx "Coloured display" .
6016 \*(BO\*(OP Whether colour shall be used for output that is paged through
6018 Note that pagers may need special flags, e.g.,
6026 in order to support colours.
6027 Often doing manual adjustments is unnecessary since \*(UA may perform
6028 adjustments dependend on the value of the environment variable
6030 (see there for more).
6034 In a(n interactive) terminal session, then if this valued option is set
6035 it'll be used as a threshold to determine how many lines the given
6036 output has to span before it will be displayed via the configured
6040 can be forced by setting this to the value
6042 setting it without a value will deduce the current height of the
6043 terminal screen to compute the treshold (see
6051 \*(OB A variable counterpart of the
6053 command (see there for documentation), interpreted as a comma-separated
6054 list of custom headers to be injected, to include commas in the header
6055 bodies escape them with reverse solidus, e.g.:
6057 .Dl set customhdr='Hdr1: Body1-1\e, Body1-2, Hdr2: Body2'
6063 the message date, if any is to be displayed according to the format of
6065 is by default taken from the
6067 line of the message.
6068 If this variable is set the date as given in the
6070 header field is used instead, converted to local time.
6071 To control the display format of the date assign a valid
6076 format should not be used, because \*(UA doesn't take embedded newlines
6077 into account when calculating how many lines fit onto the screen.)
6079 .Va datefield-markout-older .
6082 .It Va datefield-markout-older
6083 This option, when set in addition to
6087 messages (concept is rather comparable to the
6089 option of the POSIX utility
6091 The content interpretation is identical to
6096 \*(BO Enables debug messages and obsoletion warnings, disables the
6097 actual delivery of messages and also implies
6103 .It Va disposition-notification-send
6105 .Ql Disposition-Notification-To:
6106 header (RFC 3798) with the message.
6110 .\" TODO .It Va disposition-notification-send-HOST
6112 .\".Va disposition-notification-send
6113 .\" for SMTP accounts on a specific host.
6114 .\" TODO .It Va disposition-notification-send-USER@HOST
6116 .\".Va disposition-notification-send
6117 .\"for a specific account.
6121 \*(BO When dot is set, a period
6123 on a line by itself during message input in (interactive) compose mode
6124 will be treated as end-of-message (in addition to the normal end-of-file
6133 .It Va dotlock-ignore-error
6134 \*(BO\*(OP Synchronization of mailboxes which \*(UA treats as system
6135 mailboxes (see the command
6137 will be protected with so-called dotlock files\(emthe traditional mail
6138 spool file locking method\(emin addition to system file locking.
6139 Because \*(UA ships with a privilege-separated dotlock creation program
6140 that should always be able to create such a dotlock file there is no
6141 good reason to ignore dotlock file creation errors, and thus these are
6142 fatal unless this variable is set.
6146 \*(BO If this variable is set then the editor is started automatically
6147 when a message is composed in interactive mode, as if the
6153 variable is implied for this automatically spawned editor session.
6157 \*(BO When a message is edited while being composed,
6158 its header is included in the editable text.
6168 fields are accepted within the header, other fields are ignored.
6172 \*(BO When entering interactive mode \*(UA normally writes
6173 .Dq \&No mail for user
6174 and exits immediately if a mailbox is empty or doesn't exist.
6175 If this option is set \*(UA starts even with an empty or nonexistent
6176 mailbox (the latter behaviour furtherly depends upon
6182 Suggestion for the MIME encoding to use in outgoing text messages
6184 Valid values are the default
6185 .Ql quoted-printable ,
6190 may cause problems when transferring mail messages over channels that
6191 are not ESMTP (RFC 1869) compliant.
6192 If there is no need to encode a message,
6194 transfer mode is always used regardless of this variable.
6195 Binary data is always encoded as
6200 If defined, the first character of this option
6201 gives the character to use in place of
6204 .Sx "TILDE ESCAPES" .
6208 If not set then file and command pipeline targets are not allowed,
6209 and any such address will be filtered out, giving a warning message.
6210 If set without a value then all possible recipient address
6211 specifications will be accepted \(en see the section
6212 .Sx "On sending mail, and non-interactive mode"
6214 To accept them, but only in interactive mode, or when tilde commands
6215 were enabled explicitly by using one of the command line options
6219 set this to the (case-insensitive) value
6221 (note right now this is actually like setting
6222 .Ql restrict,-all,+name,+addr ) .
6224 In fact the value is interpreted as a comma-separated list of values.
6227 then the existence of disallowed specifications is treated as a hard
6228 send error instead of only filtering them out.
6229 The remaining values specify whether a specific type of recipient
6230 address specification is allowed (optionally indicated by a plus sign
6232 prefix) or disallowed (prefixed with a hyphen
6236 addresses all possible address specifications,
6240 command pipeline targets,
6242 plain user names and (MTA) aliases (\*(OB
6244 may be used as an alternative syntax to
6249 These kind of values are interpreted in the given order, so that
6250 .Ql restrict,\:fail,\:+file,\:-all,\:+addr
6251 will cause hard errors for any non-network address recipient address
6252 unless \*(UA is in interactive mode or has been started with the
6256 command line option; in the latter case(s) any address may be used, then.
6260 Unless this variable is set additional
6262 (Mail-Transfer-Agent)
6263 arguments from the command line, as can be given after a
6265 separator, are ignored due to safety reasons.
6266 However, if set to the special (case-insensitive) value
6268 then the presence of additional MTA arguments is treated as a hard
6269 error that causes \*(UA to exit with failure status.
6270 A lesser strict variant is the otherwise identical
6272 which does accept such arguments in interactive mode, or if tilde
6273 commands were enabled explicitly by using one of the command line options
6280 \*(RO String giving a list of features \*(UA, preceded with a plus-sign
6282 if the feature is available, and a minus-sign
6285 The output of the command
6287 will include this information.
6291 \*(BO This option reverses the meanings of a set of reply commands,
6292 turning the lowercase variants, which by default address all recipients
6293 included in the header of a message
6294 .Pf ( Ic reply , respond , followup )
6295 into the uppercase variants, which by default address the sender only
6296 .Pf ( Ic Reply , Respond , Followup )
6299 .Ic replysender , respondsender , followupsender
6301 .Ic replyall , respondall , followupall
6302 are not affected by the current setting of
6307 .It Va file-hook-load-EXTENSION , file-hook-save-EXTENSION
6308 It is possible to install file hooks which will be used by the
6310 command in order to be able to transparently handle (through an
6311 intermediate temporary file) files with specific
6313 s: the variable values can include shell snippets and are expected to
6314 write data to standard output / read data from standard input,
6316 \*(ID The variables may not be changed while there is a mailbox
6318 .Bd -literal -offset indent
6319 set file-hook-load-xy='echo >&2 XY-LOAD; gzip -cd' \e
6320 file-hook-save-xy='echo >&2 XY-SAVE; gzip -c' \e
6321 record=+null-sent.xy
6326 The default path under which mailboxes are to be saved:
6327 file names that begin with the plus-sign
6329 will be expanded by prefixing them with the value of this variable.
6330 The same special syntax conventions as documented for the
6332 command may be used; if the non-empty value doesn't start with a solidus
6336 will be prefixed automatically.
6337 If unset or the empty string any
6339 prefixing file names will remain unexpanded.
6343 This variable can be set to the name of a
6345 macro which will be called whenever a
6348 The macro will also be invoked when new mail arrives,
6349 but message lists for commands executed from the macro
6350 only include newly arrived messages then.
6352 are activated by default in a folder hook, causing the covered settings
6353 to be reverted once the folder is left again.
6356 Macro behaviour, including option localization, will change in v15.
6357 Please be aware of that and possibly embed a version check in a resource
6361 .It Va folder-hook-FOLDER
6366 Unlike other folder specifications, the fully expanded name of a folder,
6367 without metacharacters, is used to avoid ambiguities.
6368 However, if the mailbox resides under
6372 specification is tried in addition, e.g., if
6376 (and thus relative to the user's home directory) then
6377 .Pa /home/usr1/mail/sent
6379 .Ql folder-hook-/home/usr1/mail/sent
6380 first, but then followed by
6381 .Ql folder-hook-+sent .
6385 \*(BO Controls whether a
6386 .Ql Mail-Followup-To:
6387 header is generated when sending messages to known mailing lists.
6389 .Va followup-to-honour
6391 .Ic mlist , mlsubscribe , reply
6396 .It Va followup-to-honour
6398 .Ql Mail-Followup-To:
6399 header is honoured when group-replying to a message via
6403 This is a quadoption; if set without a value it defaults to
6413 .It Va forward-as-attachment
6414 \*(BO Original messages are normally sent as inline text with the
6417 and only the first part of a multipart message is included.
6418 With this option messages are sent as unmodified MIME
6420 attachments with all of their parts included.
6424 The address (or a list of addresses) to put into the
6426 field of the message header, quoting RFC 5322:
6427 the author(s) of the message, that is, the mailbox(es) of the person(s)
6428 or system(s) responsible for the writing of the message.
6431 ing to messages these addresses are handled as if they were in the
6435 If the machine's hostname is not valid at the Internet (for example at
6436 a dialup machine) then either this variable or
6438 (\*(IN and with a defined SMTP protocol in
6441 adds even more fine-tuning capabilities),
6445 contains more than one address,
6448 variable is required (according to the standard RFC 5322).
6452 \*(BO When replying to or forwarding a message \*(UA normally removes
6453 the comment and name parts of email addresses.
6454 If this variable is set such stripping is not performed,
6455 and comments, names etc. are retained.
6459 The string to put before the text of a message with the
6463 .Va forward-as-attachment
6466 .Dq -------- Original Message --------
6467 if unset; No heading is put if it is set to the empty string.
6471 \*(BO Causes the header summary to be written at startup and after
6472 commands that affect the number of messages or the order of messages in
6473 the current folder; enabled by default.
6474 The command line option
6480 complements this and controls header summary display on folder changes.
6485 A format string to use for the summary of
6487 similar to the ones used for
6490 Format specifiers in the given string start with a percent character
6492 and may be followed by an optional decimal number indicating the field
6493 width \(em if that is negative, the field is to be left-aligned.
6494 Valid format specifiers are:
6497 .Bl -tag -compact -offset indent -width "_%%_"
6499 A plain percent character.
6502 a space character but for the current message
6504 for which it expands to
6508 a space character but for the current message
6510 for which it expands to
6513 \*(OP The spam score of the message, as has been classified via the
6516 Shows only a replacement character if there is no spam support.
6518 Message attribute character (status flag); the actual content can be
6522 The date when the message was received, or the date found in the
6526 variable is set (optionally to a date display format string).
6528 The indenting level in threaded mode.
6530 The address of the message sender.
6532 The message thread tree structure.
6533 (Note that this format doesn't support a field width.)
6535 The number of lines of the message, if available.
6539 The number of octets (bytes) in the message, if available.
6541 Message subject (if any).
6543 Message subject (if any) in double quotes.
6545 Message recipient flags: is the addressee of the message a known or
6546 subscribed mailing list \(en see
6551 The position in threaded/sorted order.
6555 .Ql %>\&%a\&%m\ %-18f\ %16d\ %4l/%\-5o\ %i%-s ,
6557 .Ql %>\&%a\&%m\ %20-f\ \ %16d\ %3l/%\-5o\ %i%-S
6568 .It Va headline-bidi
6569 Bidirectional text requires special treatment when displaying headers,
6570 because numbers (in dates or for file sizes etc.) will not affect the
6571 current text direction, in effect resulting in ugly line layouts when
6572 arabic or other right-to-left text is to be displayed.
6573 On the other hand only a minority of terminals is capable to correctly
6574 handle direction changes, so that user interaction is necessary for
6576 Note that extended host system support is required nonetheless, e.g.,
6577 detection of the terminal character set is one precondition;
6578 and this feature only works in an Unicode (i.e., UTF-8) locale.
6580 In general setting this variable will cause \*(UA to encapsulate text
6581 fields that may occur when displaying
6583 (and some other fields, like dynamic expansions in
6585 with special Unicode control sequences;
6586 it is possible to fine-tune the terminal support level by assigning
6588 no value (or any value other than
6593 will make \*(UA assume that the terminal is capable to properly deal
6594 with Unicode version 6.3, in which case text is embedded in a pair of
6595 U+2068 (FIRST STRONG ISOLATE) and U+2069 (POP DIRECTIONAL ISOLATE)
6597 In addition no space on the line is reserved for these characters.
6599 Weaker support is chosen by using the value
6601 (Unicode 6.3, but reserve the room of two spaces for writing the control
6602 sequences onto the line).
6607 select Unicode 1.1 support (U+200E, LEFT-TO-RIGHT MARK); the latter
6608 again reserves room for two spaces in addition.
6612 \*(OP If a line editor is available then this can be set to
6613 name the (expandable) path of the location of a permanent history file.
6616 .It Va history-gabby
6617 \*(BO\*(OP Add more entries to the history as is normally done.
6620 .It Va history-gabby-persist
6621 \*(BO\*(OP \*(UA's own MLE will not save the additional
6623 entries in persistent storage unless this variable is set.
6624 On the other hand it will not loose the knowledge of whether
6625 a persistent entry was gabby or not.
6631 \*(OP If a line editor is available this value restricts the
6632 amount of history entries that are saved into a set and valid
6634 A value of less than 0 disables this feature;
6635 note that loading and incorporation of
6637 upon program startup can also be suppressed by doing this.
6638 If unset or 0, a default value will be used.
6639 Dependent on the available line editor this will also define the
6640 number of history entries in memory;
6641 it is also editor-specific whether runtime updates of this value will
6646 \*(BO This option is used to hold messages in the system
6648 box, and it is set by default.
6652 Use this string as hostname when expanding local addresses instead of
6653 the value obtained from
6662 Note that when SMTP transport is not used (via
6664 then it is normally the responsibility of the MTA to create these
6665 fields, \*(IN in conjunction with SMTP however
6667 also influences the results:
6668 you should produce some test messages with the desired combination of
6677 \*(BO\*(OP Can be used to turn off the automatic conversion of domain
6678 names according to the rules of IDNA (internationalized domain names
6680 Since the IDNA code assumes that domain names are specified with the
6682 character set, an UTF-8 locale charset is required to represent all
6683 possible international domain names (before conversion, that is).
6687 \*(BO Ignore interrupt signals from the terminal while entering
6688 messages; instead echo them as
6690 characters and discard the current line.
6694 \*(BO Ignore end-of-file conditions
6695 .Pf ( Ql control-D )
6696 in compose mode on message input and in interactive command input.
6697 If set an interactive command input session can only be left by
6698 explicitly using one of the commands
6702 and message input in compose mode can only be terminated by entering
6705 on a line by itself or by using the
6707 .Sx "TILDE ESCAPES" ;
6709 overrides a setting of
6721 option for indenting messages,
6722 in place of the normal tabulator character
6724 which is the default.
6725 Be sure to quote the value if it contains spaces or tabs.
6729 \*(BO If set, an empty mailbox file is not removed.
6730 This may improve the interoperability with other mail user agents
6731 when using a common folder directory, and prevents malicious users
6732 from creating fake mailboxes in a world-writable spool directory.
6733 Note this only applies to local regular (MBOX) files, other mailbox
6734 types will never be removed.
6737 .It Va keep-content-length
6738 \*(BO When (editing messages and) writing
6740 mailbox files \*(UA can be told to keep the
6744 header fields that some MUAs generate by setting this variable.
6745 Since \*(UA does neither use nor update these non-standardized header
6746 fields (which in itself shows one of their conceptual problems),
6747 stripping them should increase interoperability in between MUAs that
6748 work with with same mailbox files.
6749 Note that, if this is not set but
6750 .Va writebackedited ,
6751 as below, is, a possibly performed automatic stripping of these header
6752 fields already marks the message as being modified.
6756 \*(BO When a message is saved it is usually discarded from the
6757 originating folder when \*(UA is quit.
6758 Setting this option causes all saved message to be retained.
6761 .It Va line-editor-disable
6762 \*(BO Turn off any enhanced line editing capabilities (see
6763 .Sx "On terminal control and line editor"
6767 .It Va line-editor-no-defaults
6768 \*(BO\*(OP Do not establish any default key binding.
6772 \*(BO When a message is replied to and this variable is set,
6773 it is marked as having been answered.
6774 This mark has no technical meaning in the mail system;
6775 it just causes messages to be marked in the header summary,
6776 and makes them specially addressable.
6780 \*(BO \*(UA generates and expects RFC 4155 compliant MBOX text
6782 (With the restriction that RFC 4155 defines seven-bit clean data
6783 storage, but which can be overwritten by a contrary setting of
6785 Messages which are fetched over the network or from within already
6786 existing Maildir (or any non-MBOX) mailboxes may require so-called
6788 quoting (insertion of additional
6790 characters to prevent line content misinterpretation) to be applied in
6791 order to be storable in MBOX mailboxes, however, dependent on the
6792 circumspection of the message producer.
6793 E.g., \*(UA itself will, when newly generating messages, choose a
6794 .Pf Content-Transfer- Va encoding
6795 that prevents the necessity for such quoting \(en a necessary
6796 precondition to ensure message checksums won't change.
6798 By default \*(UA will perform this
6800 quoting in a way that results in a MBOX file that is compatible with
6801 the POSIX MBOX layout, which means that, in order not to exceed the
6802 capabilities of simple applications, many more
6804 lines get quoted (thus modified) than necessary according to RFC 4155.
6805 Set this option to instead generate MBOX files which comply to RFC 4155.
6809 \*(BO Internal development variable.
6812 .It Va message-id-disable
6813 \*(BO By setting this option the generation of
6815 can be completely suppressed, effectively leaving this task up to the
6817 (Mail-Transfer-Agent) or the SMTP server.
6818 (According to RFC 5321 your SMTP server is not required to add this
6819 field by itself, so you should ensure that it accepts messages without a
6823 .It Va message-inject-head
6824 A string to put at the beginning of each new message.
6825 The escape sequences tabulator
6832 .It Va message-inject-tail
6833 A string to put at the end of each new message.
6834 The escape sequences tabulator
6842 \*(BO Usually, when an
6844 expansion contains the sender, the sender is removed from the expansion.
6845 Setting this option suppresses these removals.
6850 option to be passed through to the
6852 (Mail-Transfer-Agent); though most of the modern MTAs no longer document
6853 this flag, no MTA is known which doesn't support it (for historical
6857 .It Va mime-allow-text-controls
6858 \*(BO When sending messages, each part of the message is MIME-inspected
6859 in order to classify the
6862 .Ql Content-Transfer-Encoding:
6865 that is required to send this part over mail transport, i.e.,
6866 a computation rather similar to what the
6868 command produces when used with the
6872 This classification however treats text files which are encoded in
6873 UTF-16 (seen for HTML files) and similar character sets as binary
6874 octet-streams, forcefully changing any
6879 .Ql application/octet-stream :
6880 If that actually happens a yet unset charset MIME parameter is set to
6882 effectively making it impossible for the receiving MUA to automatically
6883 interpret the contents of the part.
6885 If this option is set, and the data was unambiguously identified as text
6886 data at first glance (by a
6890 file extension), then the original
6892 will not be overwritten.
6895 .It Va mime-alternative-favour-rich
6896 \*(BO If this variable is set then rich MIME alternative parts (e.g.,
6897 HTML) will be preferred in favour of included plain text versions when
6898 displaying messages, provided that a handler exists which produces
6899 output that can be (re)integrated into \*(UA's normal visual display.
6900 (E.g., at the time of this writing some newsletters ship their full
6901 content only in the rich HTML part, whereas the plain text part only
6902 contains topic subjects.)
6905 .It Va mime-counter-evidence
6908 field is used to decide how to handle MIME parts.
6909 Some MUAs however don't use
6911 or a similar mechanism to correctly classify content, but simply specify
6912 .Ql application/octet-stream ,
6913 even for plain text attachments like
6915 If this variable is set then \*(UA will try to classify such MIME
6916 message parts on its own, if possible, for example via a possibly
6917 existent attachment filename.
6918 A non-empty value may also be given, in which case a number is expected,
6919 actually a carrier of bits.
6920 Creating the bit-carrying number is a simple addition:
6921 .Bd -literal -offset indent
6922 ? !echo Value should be set to $((2 + 4 + 8))
6923 Value should be set to 14
6926 .Bl -bullet -compact
6928 If bit two is set (2) then the detected
6930 content-type will be carried along with the message and be used for
6932 .Va pipe-TYPE/SUBTYPE
6933 is responsible for the MIME part, shall that question arise;
6934 when displaying such a MIME part the part-info will indicate the
6935 overridden content-type by showing a plus-sign
6938 If bit three is set (4) then the counter-evidence is always produced
6939 and a positive result will be used as the MIME type, even forcefully
6940 overriding the parts given MIME type.
6942 If bit four is set (8) then as a last resort the actual content of
6943 .Ql application/octet-stream
6944 parts will be inspected, so that data which looks like plain text can be
6949 .It Va mimetypes-load-control
6950 This option can be used to control which of the
6952 databases are loaded by \*(UA, as furtherly described in the section
6953 .Sx "The mime.types files" .
6956 is part of the option value, then the user's personal
6958 file will be loaded (if it exists); likewise the letter
6960 controls loading of the system wide
6961 .Pa /etc/mime.types ;
6962 directives found in the user file take precedence, letter matching is
6964 If this option is not set \*(UA will try to load both files.
6965 Incorporation of the \*(UA-builtin MIME types cannot be suppressed,
6966 but they will be matched last.
6968 More sources can be specified by using a different syntax: if the
6969 value string contains an equals sign
6971 then it is instead parsed as a comma-separated list of the described
6974 pairs; the given filenames will be expanded and loaded, and their
6975 content may use the extended syntax that is described in the section
6976 .Sx "The mime.types files" .
6977 Directives found in such files always take precedence (are prepended to
6978 the MIME type cache).
6983 To choose an alternate Mail-Transfer-Agent, set this option to either
6984 the full pathname of an executable (optionally prefixed with a
6986 protocol indicator), or \*(OPally a SMTP protocol URL, e.g., \*(IN
6988 .Dl smtps?://[user[:password]@]server[:port]
6991 .Ql [smtp://]server[:port] . )
6992 The default has been chosen at compie time.
6993 All supported data transfers are executed in child processes, which
6994 run asynchronously, and without supervision, unless either the
6999 If such a child receives a TERM signal, it will abort and
7006 For a file-based MTA it may be necessary to set
7008 in in order to choose the right target of a modern
7011 It will be passed command line arguments from several possible sources:
7014 if set, from the command line if given and the variable
7017 Argument processing of the MTA will be terminated with a
7022 The otherwise occurring implicit usage of the following MTA command
7023 line arguments can be disabled by setting the boolean option
7024 .Va mta-no-default-arguments
7025 (which will also disable passing
7029 (for not treating a line with only a dot
7031 character as the end of input),
7039 option is set); in conjunction with the
7041 command line option \*(UA will also pass
7047 \*(OP \*(UA can send mail over SMTP network connections to a single
7048 defined SMTP smarthost, the access URL of which has to be assigned to
7050 To use this mode it is helpful to read
7051 .Sx "On URL syntax and credential lookup" .
7052 It may be necessary to set the
7054 variable in order to use a specific combination of
7059 with some mail providers.
7062 .Bl -bullet -compact
7064 The plain SMTP protocol (RFC 5321) that normally lives on the
7065 server port 25 and requires setting the
7066 .Va smtp-use-starttls
7067 variable to enter a SSL/TLS encrypted session state.
7068 Assign a value like \*(IN
7069 .Ql smtp://[user[:password]@]server[:port]
7071 .Ql smtp://server[:port] )
7072 to choose this protocol.
7074 The so-called SMTPS which is supposed to live on server port 465
7075 and is automatically SSL/TLS secured.
7076 Unfortunately it never became a standardized protocol and may thus not
7077 be supported by your hosts network service database
7078 \(en in fact the port number has already been reassigned to other
7081 SMTPS is nonetheless a commonly offered protocol and thus can be
7082 chosen by assigning a value like \*(IN
7083 .Ql smtps://[user[:password]@]server[:port]
7085 .Ql smtps://server[:port] ) ;
7086 due to the mentioned problems it is usually necessary to explicitly
7091 Finally there is the SUBMISSION protocol (RFC 6409), which usually
7092 lives on server port 587 and is practically identically to the SMTP
7093 protocol from \*(UA's point of view beside that; it requires setting the
7094 .Va smtp-use-starttls
7095 variable to enter a SSL/TLS secured session state.
7096 Assign a value like \*(IN
7097 .Ql submission://[user[:password]@]server[:port]
7099 .Ql submission://server[:port] ) .
7104 .It Va mta-arguments
7105 Arguments to pass through to a file-based
7107 can be given via this variable, the content of which will be split up in
7108 a vector of arguments, to be joined onto other possible MTA options:
7110 .Dl set mta-arguments='-t -X \&"/tmp/my log\&"'
7113 .It Va mta-no-default-arguments
7114 \*(BO Unless this option is set \*(UA will pass some well known
7115 standard command line options to a file-based
7117 (Mail-Transfer-Agent), see there for more.
7121 Many systems use a so-called
7123 environment to ensure compatibility with
7125 This works by inspecting the name that was used to invoke the mail
7127 If this variable is set then the mailwrapper (the program that is
7128 actually executed when calling the file-based
7130 will treat its contents as that name.
7135 .It Va NAIL_EXTRA_RC
7136 The name of an optional startup file to be read last.
7137 This variable has an effect only if it is set in any of the
7138 .Sx "Resource files" ,
7139 it is not imported from the environment.
7140 Use this file for commands that are not understood by other POSIX
7145 .It Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup
7146 \*(BO\*(IN\*(OP Used to control usage of the users
7148 file for lookup of account credentials, as documented in the section
7149 .Sx "On URL syntax and credential lookup"
7153 .Sx "The .netrc file"
7154 documents the file format.
7166 then \*(UA will read the output of a shell pipe instead of the users
7168 file if this variable is set (to the desired shell command).
7169 This can be used to, e.g., store
7173 .Dl set netrc-pipe='gpg -qd ~/.netrc.pgp'
7177 If this variable has the value
7179 newly created local folders will be in Maildir format.
7183 Checks for new mail in the current folder each time the prompt is shown.
7184 A Maildir folder must be re-scanned to determine if new mail has arrived.
7185 If this variable is set to the special value
7187 then a Maildir folder will not be rescanned completely, but only
7188 timestamp changes are detected.
7192 .It Va on-compose-enter , on-compose-leave
7193 \*(ID Macro hooks which will be executed before compose mode is
7194 entered, and after composing has been finished, respectively.
7195 Please note that this interface is very likely to change in v15, and
7196 should therefore possibly even be seen as experimental.
7198 are by default enabled for these hooks, causing any setting to be
7199 forgotten after the message has been sent.
7200 The following variables will be set temporarily during execution of the
7203 .Bl -tag -compact -width ".It Va compose_subject"
7206 .It Va compose-sender
7208 .It Va compose-to , compose-cc , compose-bcc
7209 The list of receiver addresses as a space-separated list.
7210 .It Va compose-subject
7216 \*(BO Causes the filename given in the
7219 and the sender-based filenames for the
7223 commands to be interpreted relative to the directory given in the
7225 variable rather than to the current directory,
7226 unless it is set to an absolute pathname.
7230 \*(BO If set, each message feed through the command given for
7232 is followed by a formfeed character
7236 .It Va password-USER@HOST , password-HOST , password
7237 \*(IN Variable chain that sets a password, which is used in case none has
7238 been given in the protocol and account-specific URL;
7239 as a last resort \*(UA will ask for a password on the user's terminal if
7240 the authentication method requires a password.
7241 Specifying passwords in a startup file is generally a security risk;
7242 the file should be readable by the invoking user only.
7244 .It Va password-USER@HOST
7245 \*(OU (see the chain above for \*(IN)
7246 Set the password for
7250 If no such variable is defined for a host,
7251 the user will be asked for a password on standard input.
7252 Specifying passwords in a startup file is generally a security risk;
7253 the file should be readable by the invoking user only.
7257 \*(BO Send messages to the
7259 command without performing MIME and character set conversions.
7263 .It Va pipe-TYPE/SUBTYPE
7264 When a MIME message part of type
7266 (case-insensitive) is displayed or quoted,
7267 its text is filtered through the value of this variable interpreted as
7271 forces interpretation of the message part as plain text, e.g.,
7272 .Ql set pipe-application/xml=@
7273 will henceforth display XML
7275 (The same could also be achieved by adding a MIME type marker with the
7278 And \*(OPally MIME type handlers may be defined via
7279 .Sx "The Mailcap files"
7280 \(em corresponding flag strings are shown in parenthesis below.)
7285 can in fact be used to adjust usage and behaviour of a following shell
7286 command specification by appending trigger characters to it, e.g., the
7287 following hypothetical command specification could be used:
7288 .Bd -literal -offset indent
7289 set pipe-X/Y='@*!++=@vim ${NAIL_FILENAME_TEMPORARY}'
7293 .Bl -tag -compact -width ".It Ql __"
7295 Simply by using the special
7297 prefix the MIME type (shell command) handler will only be invoked to
7298 display or convert the MIME part if the message is addressed directly
7299 and alone by itself.
7300 Use this trigger to disable this and always invoke the handler
7301 .Pf ( Cd x-mailx-always ) .
7304 If set the handler will not be invoked when a message is to be quoted,
7305 but only when it will be displayed
7306 .Pf ( Cd x-mailx-noquote ) .
7309 The command will be run asynchronously, i.e., without blocking \*(UA,
7310 which may be a handy way to display a, e.g., PDF file while also
7311 continuing to read the mail message
7312 .Pf ( Cd x-mailx-async ) .
7313 Asynchronous execution implies
7317 The command must be run on an interactive terminal, \*(UA will
7318 temporarily release the terminal to it
7319 .Pf ( Cd needsterminal ) .
7320 This flag is mutual exclusive with
7322 will only be used in interactive mode and implies
7326 Request creation of a zero-sized temporary file, the absolute pathname
7327 of which will be made accessible via the environment variable
7328 .Ev NAIL_FILENAME_TEMPORARY
7329 .Pf ( Cd x-mailx-tmpfile ) .
7330 If this trigger is given twice then the file will be unlinked
7331 automatically by \*(UA when the command loop is entered again at latest
7332 .Pf ( Cd x-mailx-tmpfile-unlink ) .
7333 (Don't use this for asynchronous handlers.)
7336 Normally the MIME part content is passed to the handler via standard
7337 input; if this flag is set then the data will instead be written into
7338 .Ev NAIL_FILENAME_TEMPORARY
7339 .Pf ( Cd x-mailx-tmpfile-fill ) ,
7340 the creation of which is implied; note however that in order to cause
7341 deletion of the temporary file you still have to use two plus signs
7346 To avoid ambiguities with normal shell command content you can use
7347 another at-sign to forcefully terminate interpretation of remaining
7349 (Any character not in this list will have the same effect.)
7353 Some information about the MIME part to be displayed is embedded into
7354 the environment of the shell command:
7357 .Bl -tag -compact -width ".It Ev _AIL__ILENAME__ENERATED"
7360 The MIME content-type of the part, if known, the empty string otherwise.
7363 .It Ev NAIL_CONTENT_EVIDENCE
7365 .Va mime-counter-evidence
7366 includes the carry-around-bit (2), then this will be set to the detected
7367 MIME content-type; not only then identical to
7368 .Ev \&\&NAIL_CONTENT
7372 .It Ev NAIL_FILENAME
7373 The filename, if any is set, the empty string otherwise.
7376 .It Ev NAIL_FILENAME_GENERATED
7380 .It Ev NAIL_FILENAME_TEMPORARY
7381 If temporary file creation has been requested through the command prefix
7382 this variable will be set and contain the absolute pathname of the
7387 The temporary directory that \*(UA uses.
7388 Usually identical to
7390 but guaranteed to be set and usable by child processes;
7391 to ensure the latter condition for
7398 .It Va pipe-EXTENSION
7399 This is identical to
7400 .Va pipe-TYPE/SUBTYPE
7403 (normalized to lowercase using character mappings of the ASCII charset)
7404 names a file extension, e.g.,
7406 Handlers registered using this method take precedence.
7409 .It Va pop3-auth-USER@HOST , pop3-auth-HOST , pop3-auth
7410 \*(OP\*(IN Variable chain that sets the POP3 authentication method.
7411 The only possible value as of now is
7413 which is thus the default.
7416 .Mx Va pop3-bulk-load
7417 .It Va pop3-bulk-load-USER@HOST , pop3-bulk-load-HOST , pop3-bulk-load
7418 \*(BO\*(OP When accessing a POP3 server \*(UA loads the headers of
7419 the messages, and only requests the message bodies on user request.
7420 For the POP3 protocol this means that the message headers will be
7422 If this option is set then \*(UA will download only complete messages
7423 from the given POP3 server(s) instead.
7425 .Mx Va pop3-keepalive
7426 .It Va pop3-keepalive-USER@HOST , pop3-keepalive-HOST , pop3-keepalive
7427 \*(OP POP3 servers close the connection after a period of inactivity;
7428 the standard requires this to be at least 10 minutes,
7429 but practical experience may vary.
7430 Setting this variable to a numeric value greater than
7434 command to be sent each value seconds if no other operation is performed.
7437 .It Va pop3-no-apop-USER@HOST , pop3-no-apop-HOST , pop3-no-apop
7438 \*(BO\*(OP Unless this variable is set the
7440 authentication method will be used when connecting to a POP3 server that
7444 is that the password is not sent in clear text over the wire and that
7445 only a single packet is sent for the user/password tuple.
7447 .Va pop3-no-apop-HOST
7450 .Mx Va pop3-use-starttls
7451 .It Va pop3-use-starttls-USER@HOST , pop3-use-starttls-HOST , pop3-use-starttls
7452 \*(BO\*(OP Causes \*(UA to issue a
7454 command to make an unencrypted POP3 session SSL/TLS encrypted.
7455 This functionality is not supported by all servers,
7456 and is not used if the session is already encrypted by the POP3S method.
7458 .Va pop3-use-starttls-HOST
7462 .It Va print-alternatives
7463 \*(BO When a MIME message part of type
7464 .Ql multipart/alternative
7465 is displayed and it contains a subpart of type
7467 other parts are normally discarded.
7468 Setting this variable causes all subparts to be displayed,
7469 just as if the surrounding part was of type
7470 .Ql multipart/mixed .
7474 The string shown when a command is accepted.
7475 Prompting may be prevented by setting this to the null string
7477 .Pf no Va prompt ) .
7478 If a value is assigned the following \*(UA specific additional sequences
7485 is set, in which case it expands to
7489 is the default value of
7492 which will expand to
7494 if the last command failed and to
7498 which will expand to the name of the currently active
7500 if any, and to the empty string otherwise, and
7502 which will expand to the name of the currently active mailbox.
7503 (Note that the prompt buffer is size-limited, excess is cut off.)
7509 to encapsulate the expansions of the
7513 escape sequences as necessary to correctly display bidirectional text,
7514 this is not true for the final string that makes up
7516 as such, i.e., real BIDI handling is not supported.
7520 \*(BO Suppresses the printing of the version when first invoked.
7524 If set, \*(UA starts a replying message with the original message
7525 prefixed by the value of the variable
7527 Normally, a heading consisting of
7528 .Dq Fromheaderfield wrote:
7529 is put before the quotation.
7534 variable, this heading is omitted.
7537 is assigned, the headers selected by the
7538 .Ic ignore Ns / Ns Ic retain
7539 commands are put above the message body,
7542 acts like an automatic
7548 is assigned, all headers are put above the message body and all MIME
7549 parts are included, making
7551 act like an automatic
7554 .Va quote-as-attachment .
7557 .It Va quote-as-attachment
7558 \*(BO Add the original message in its entirety as a
7560 MIME attachment when replying to a message.
7561 Note this works regardless of the setting of
7566 \*(OP Can be set in addition to
7568 Setting this turns on a more fancy quotation algorithm in that leading
7569 quotation characters are compressed and overlong lines are folded.
7571 can be set to either one or two (space separated) numeric values,
7572 which are interpreted as the maximum (goal) and the minimum line length,
7573 respectively, in a spirit rather equal to the
7575 program, but line-, not paragraph-based.
7576 If not set explicitly the minimum will reflect the goal algorithmically.
7577 The goal can't be smaller than the length of
7579 plus some additional pad.
7580 Necessary adjustments take place silently.
7583 .It Va recipients-in-cc
7584 \*(BO On group replies, specify only the sender of the original mail in
7586 and mention the other recipients in the secondary
7588 By default all recipients of the original mail will be addressed via
7593 If defined, gives the pathname of the folder used to record all outgoing
7595 If not defined, then outgoing mail is not saved.
7596 When saving to this folder fails the message is not sent,
7597 but instead saved to
7601 .It Va record-resent
7602 \*(BO If both this variable and the
7609 commands save messages to the
7611 folder as it is normally only done for newly composed messages.
7614 .It Va reply-in-same-charset
7615 \*(BO If this variable is set \*(UA first tries to use the same
7616 character set of the original message for replies.
7617 If this fails, the mechanism described in
7618 .Sx "Character sets"
7619 is evaluated as usual.
7622 .It Va reply_strings
7623 Can be set to a comma-separated list of (case-insensitive according to
7624 ASCII rules) strings which shall be recognized in addition to the
7627 reply message indicators \(en builtin are
7629 which is mandated by RFC 5322, as well as the german
7634 A list of addresses to put into the
7636 field of the message header.
7637 Members of this list are handled as if they were in the
7642 .It Va reply-to-honour
7645 header is honoured when replying to a message via
7649 This is a quadoption; if set without a value it defaults to
7653 .It Va rfc822-body-from_
7654 \*(BO This variable can be used to force displaying a so-called
7656 line for messages that are embedded into an envelope mail via the
7658 MIME mechanism, for more visual convenience.
7662 \*(BO Enable saving of (partial) messages in
7664 upon interrupt or delivery error.
7668 The number of lines that represents a
7677 line display and scrolling via
7679 If this variable is not set \*(UA falls back to a calculation based upon
7680 the detected terminal window size and the baud rate: the faster the
7681 terminal, the more will be shown.
7682 Overall screen dimensions and pager usage is influenced by the
7683 environment variables
7691 .It Va searchheaders
7692 \*(BO Expand message-list specifiers in the form
7694 to all messages containing the substring
7698 The string search is case insensitive.
7702 \*(OP A comma-separated list of character set names that can be used in
7703 outgoing internet mail.
7704 The value of the variable
7706 is automatically appended to this list of character-sets.
7707 If no character set conversion capabilities are compiled into \*(UA then
7708 the only supported charset is
7711 .Va sendcharsets-else-ttycharset
7712 and refer to the section
7713 .Sx "Character sets"
7714 for the complete picture of character set conversion in \*(UA.
7717 .It Va sendcharsets-else-ttycharset
7718 \*(BO\*(OP If this variable is set, but
7720 is not, then \*(UA acts as if
7722 had been set to the value of the variable
7724 In effect this combination passes through the message data in the
7725 character set of the current locale (given that
7727 hasn't been set manually), i.e., without converting it to the
7729 fallback character set.
7730 Thus, mail message text will be in ISO-8859-1 encoding when send from
7731 within a ISO-8859-1 locale, and in UTF-8 encoding when send from within
7733 If no character set conversion capabilities are available in \*(UA then
7734 the only supported character set is
7739 An address that is put into the
7741 field of outgoing messages, quoting RFC 5322: the mailbox of the agent
7742 responsible for the actual transmission of the message.
7743 This field should normally not be used unless the
7745 field contains more than one address, on which case it is required.
7748 address is handled as if it were in the
7754 \*(OB Predecessor of
7758 .It Va sendmail-arguments
7759 \*(OB Predecessor of
7763 .It Va sendmail-no-default-arguments
7764 \*(OB\*(BO Predecessor of
7765 .Va mta-no-default-arguments .
7768 .It Va sendmail-progname
7769 \*(OB Predecessor of
7774 \*(BO When sending a message wait until the
7776 (including the builtin SMTP one) exits before accepting further commands.
7778 with this variable set errors reported by the MTA will be recognizable!
7779 If the MTA returns a non-zero exit status,
7780 the exit status of \*(UA will also be non-zero.
7784 \*(BO Setting this option causes \*(UA to start at the last message
7785 instead of the first one when opening a mail folder.
7789 \*(BO Causes \*(UA to use the sender's real name instead of the plain
7790 address in the header field summary and in message specifications.
7794 \*(BO Causes the recipient of the message to be shown in the header
7795 summary if the message was sent by the user.
7799 A string for use with the
7805 A string for use with the
7811 Must correspond to the name of a readable file if set.
7812 The file's content is then appended to each singlepart message
7813 and to the first part of each multipart message.
7814 Be warned that there is no possibility to edit the signature for an
7818 .It Va skipemptybody
7819 \*(BO If an outgoing message does not contain any text in its first or
7820 only message part, do not send it but discard it silently (see also the
7826 \*(OP Specifies a directory with CA certificates in PEM (Privacy
7827 Enhanced Mail) format for verification of S/MIME signed messages.
7830 .It Va smime-ca-file
7831 \*(OP Specifies a file with CA certificates in PEM format for
7832 verification of S/MIME signed messages.
7835 .It Va smime-cipher-USER@HOST , smime-cipher
7836 \*(OP Specifies the cipher to use when generating S/MIME encrypted
7837 messages (for the specified account).
7838 RFC 5751 mandates a default of
7841 Possible values are (case-insensitive and) in decreasing cipher strength:
7849 (DES EDE3 CBC, 168 bits; default if
7851 isn't available) and
7855 The actually available cipher algorithms depend on the cryptographic
7856 library that \*(UA uses.
7857 \*(OP Support for more cipher algorithms may be available through
7858 dynamic loading via, e.g.,
7859 .Xr EVP_get_cipherbyname 3
7860 (OpenSSL) if \*(UA has been compiled to support this.
7863 .It Va smime-crl-dir
7864 \*(OP Specifies a directory that contains files with CRLs in PEM format
7865 to use when verifying S/MIME messages.
7868 .It Va smime-crl-file
7869 \*(OP Specifies a file that contains a CRL in PEM format to use when
7870 verifying S/MIME messages.
7873 .It Va smime-encrypt-USER@HOST
7874 \*(OP If this variable is set, messages send to the given receiver are
7875 encrypted before sending.
7876 The value of the variable must be set to the name of a file that
7877 contains a certificate in PEM format.
7879 If a message is sent to multiple recipients,
7880 each of them for whom a corresponding variable is set will receive an
7881 individually encrypted message;
7882 other recipients will continue to receive the message in plain text
7884 .Va smime-force-encryption
7886 It is recommended to sign encrypted messages, i.e., to also set the
7891 .It Va smime-force-encryption
7892 \*(BO\*(OP Causes \*(UA to refuse sending unencrypted messages.
7895 .It Va smime-no-default-ca
7896 \*(BO\*(OP Don't load default CA locations when verifying S/MIME signed
7901 \*(BO\*(OP S/MIME sign outgoing messages with the user's private key
7902 and include the user's certificate as a MIME attachment.
7903 Signing a message enables a recipient to verify that the sender used
7904 a valid certificate,
7905 that the email addresses in the certificate match those in the message
7906 header and that the message content has not been altered.
7907 It does not change the message text,
7908 and people will be able to read the message as usual.
7910 .Va smime-sign-cert , smime-sign-include-certs
7912 .Va smime-sign-message-digest .
7914 .Mx Va smime-sign-cert
7915 .It Va smime-sign-cert-USER@HOST , smime-sign-cert
7916 \*(OP Points to a file in PEM format.
7917 For the purpose of signing and decryption this file needs to contain the
7918 user's private key as well as his certificate.
7922 is always derived from the value of
7924 (or, if that contains multiple addresses,
7926 For the purpose of encryption the recipient's public encryption key
7927 (certificate) is expected; the command
7929 can be used to save certificates of signed messages (the section
7930 .Sx "Signed and encrypted messages with S/MIME"
7931 gives some details).
7932 This mode of operation is usually driven by the specialized form.
7934 When decrypting messages the account is derived from the recipient
7939 of the message, which are searched for addresses for which such
7941 \*(UA always uses the first address that matches,
7942 so if the same message is sent to more than one of the user's addresses
7943 using different encryption keys, decryption might fail.
7945 .Mx Va smime-sign-include-certs
7946 .It Va smime-sign-include-certs-USER@HOST , smime-sign-include-certs
7947 \*(OP If used, this is supposed to a consist of a comma-separated list
7948 of files, each of which containing a single certificate in PEM format to
7949 be included in the S/MIME message in addition to the
7952 This is most useful for long certificate chains if it is desired to aid
7953 the receiving party's verification process.
7954 Note that top level certificates may also be included in the chain but
7955 don't play a role for verification.
7957 .Va smime-sign-cert .
7958 Remember that for this
7960 refers to the variable
7962 (or, if that contains multiple addresses,
7965 .Mx Va smime-sign-message-digest
7966 .It Va smime-sign-message-digest-USER@HOST , smime-sign-message-digest
7967 \*(OP Specifies the message digest to use when signing S/MIME messages.
7968 RFC 5751 mandates a default of
7970 Possible values are (case-insensitive and) in decreasing cipher strength:
7978 The actually available message digest algorithms depend on the
7979 cryptographic library that \*(UA uses.
7980 \*(OP Support for more message digest algorithms may be available
7981 through dynamic loading via, e.g.,
7982 .Xr EVP_get_digestbyname 3
7983 (OpenSSL) if \*(UA has been compiled to support this.
7984 Remember that for this
7986 refers to the variable
7988 (or, if that contains multiple addresses,
7993 \*(OB\*(OP To use the builtin SMTP transport, specify a SMTP URL in
7995 \*(ID For compatibility reasons a set
7997 is used in preference of
8001 .It Va smtp-auth-USER@HOST , smtp-auth-HOST , smtp-auth
8002 \*(OP Variable chain that controls the SMTP
8004 authentication method, possible values are
8010 as well as the \*(OPal methods
8016 method doesn't need any user credentials,
8018 requires a user name and all other methods require a user name and
8026 .Va smtp-auth-password
8028 .Va smtp-auth-user ) .
8033 .Va smtp-auth-USER@HOST :
8034 may override dependent on sender address in the variable
8037 .It Va smtp-auth-password
8038 \*(OP\*(OU Sets the global fallback password for SMTP authentication.
8039 If the authentication method requires a password, but neither
8040 .Va smtp-auth-password
8042 .Va smtp-auth-password-USER@HOST
8044 \*(UA will ask for a password on the user's terminal.
8046 .It Va smtp-auth-password-USER@HOST
8048 .Va smtp-auth-password
8049 for specific values of sender addresses, dependent upon the variable
8052 .It Va smtp-auth-user
8053 \*(OP\*(OU Sets the global fallback user name for SMTP authentication.
8054 If the authentication method requires a user name, but neither
8057 .Va smtp-auth-user-USER@HOST
8059 \*(UA will ask for a user name on the user's terminal.
8061 .It Va smtp-auth-user-USER@HOST
8064 for specific values of sender addresses, dependent upon the variable
8068 .It Va smtp-hostname
8069 \*(OP\*(IN Normally \*(UA uses the variable
8071 to derive the necessary
8073 information in order to issue a
8080 can be used to use the
8082 from the SMTP account
8089 from the content of this variable (or, if that is the empty string,
8091 or the local hostname as a last resort).
8092 This often allows using an address that is itself valid but hosted by
8093 a provider other than which (in
8095 is about to send the message.
8096 Setting this variable also influences the generated
8099 .Mx Va smtp-use-starttls
8100 .It Va smtp-use-starttls-USER@HOST , smtp-use-starttls-HOST , smtp-use-starttls
8101 \*(BO\*(OP Causes \*(UA to issue a
8103 command to make an SMTP
8105 session SSL/TLS encrypted, i.e., to enable transport layer security.
8109 .It Va spam-interface
8110 \*(OP In order to use any of the spam-related commands (like, e.g.,
8112 the desired spam interface must be defined by setting this variable.
8113 Please refer to the manual section
8115 for the complete picture of spam handling in \*(UA.
8116 All or none of the following interfaces may be available:
8118 .Bl -tag -width ".It Ql _ilte_"
8124 .Pf ( Lk http://spamassassin.apache.org SpamAssassin )
8126 Different to the generic filter interface \*(UA will automatically add
8127 the correct arguments for a given command and has the necessary
8128 knowledge to parse the program's output.
8131 will have been compiled into the \*(UA binary if
8136 Shall it be necessary to define a specific connection type (rather than
8137 using a configuration file for that), the variable
8139 can be used as in, e.g.,
8140 .Ql -d server.example.com -p 783 .
8141 It is also possible to specify a per-user configuration via
8143 Note that this interface doesn't inspect the
8145 flag of a message for the command
8149 generic spam filter support via freely configurable hooks.
8150 This interface is meant for programs like
8152 and requires according behaviour in respect to the hooks' exit
8153 status for at least the command
8156 meaning a message is spam,
8160 for unsure and any other return value indicating a hard error);
8161 since the hooks can include shell code snippets diverting behaviour
8162 can be intercepted as necessary.
8164 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
8167 .Va spamfilter-spam ;
8170 contains examples for some programs.
8171 The process environment of the hooks will have the variables
8172 .Ev NAIL_TMPDIR , TMPDIR
8174 .Ev NAIL_FILENAME_GENERATED
8176 Note that spam score support for
8178 isn't supported unless the \*(OPtional regular expression support is
8180 .Va spamfilter-rate-scanscore
8187 \*(OP Messages that exceed this size won't be passed through to the
8189 .Va spam-interface .
8190 If unset or 0, the default of 420000 bytes is used.
8193 .It Va spamc-command
8194 \*(OP The path to the
8198 .Va spam-interface .
8199 Note that the path is not expanded, but used
8201 A fallback path will have been compiled into the \*(UA binary if the
8202 executable had been found during compilation.
8205 .It Va spamc-arguments
8206 \*(OP Even though \*(UA deals with most arguments for the
8209 automatically, it may at least sometimes be desirable to specify
8210 connection-related ones via this variable, e.g.,
8211 .Ql -d server.example.com -p 783 .
8215 \*(OP Specify a username for per-user configuration files for the
8217 .Va spam-interface .
8218 If this is set to the empty string then \*(UA will use the name of the
8227 .It Va spamfilter-ham , spamfilter-noham , \
8228 spamfilter-nospam , spamfilter-rate , spamfilter-spam
8229 \*(OP Command and argument hooks for the
8231 .Va spam-interface .
8234 contains examples for some programs.
8237 .It Va spamfilter-rate-scanscore
8238 \*(OP Because of the generic nature of the
8241 spam scores are not supported for it by default, but if the \*(OPtional
8242 regular expression support is available then setting this variable can
8243 be used to overcome this restriction.
8244 It is interpreted as follows: first a number (digits) is parsed that
8245 must be followed by a semicolon
8247 and an extended regular expression.
8248 Then the latter is used to parse the first output line of the
8250 hook, and, in case the evaluation is successful, the group that has been
8251 specified via the number is interpreted as a floating point scan score.
8255 \*(OP Specifies a directory with CA certificates in PEM (Pricacy
8256 Enhanced Mail) for verification of of SSL/TLS server certificates.
8258 .Xr SSL_CTX_load_verify_locations 3
8259 for more information.
8263 \*(OP Specifies a file with CA certificates in PEM format for
8264 verification of SSL/TLS server certificates.
8266 .Xr SSL_CTX_load_verify_locations 3
8267 for more information.
8270 .It Va ssl-cert-USER@HOST , ssl-cert-HOST , ssl-cert
8271 \*(OP Variable chain that sets the file name for a SSL/TLS client
8272 certificate required by some servers.
8273 This is a direct interface to the
8277 function of the OpenSSL library, if available.
8279 .Mx Va ssl-cipher-list
8280 .It Va ssl-cipher-list-USER@HOST , ssl-cipher-list-HOST , ssl-cipher-list
8281 \*(OP Specifies a list of ciphers for SSL/TLS connections.
8282 This is a direct interface to the
8286 function of the OpenSSL library, if available; see
8288 for more information.
8289 By default \*(UA doesn't set a list of ciphers, which in effect will use a
8291 specific cipher (protocol standards ship with a list of acceptable
8292 ciphers), possibly cramped to what the actually used SSL/TLS library
8293 supports \(en the manual section
8294 .Sx "An example configuration"
8295 also contains a SSL/TLS use case.
8298 .It Va ssl-config-file
8299 \*(OP If this variable is set \*(UA will call
8300 .Xr CONF_modules_load_file 3
8301 to allow OpenSSL to be configured according to the host system wide
8303 If a non-empty value is given then this will be used to specify the
8304 configuration file to be used instead of the global OpenSSL default;
8305 note that in this case it is an error if the file cannot be loaded.
8306 The application name will always be passed as
8311 \*(OP Specifies a file that contains a CRL in PEM format to use when
8312 verifying SSL/TLS server certificates.
8316 \*(OP Specifies a directory that contains files with CRLs in PEM format
8317 to use when verifying SSL/TLS server certificates.
8320 .It Va ssl-key-USER@HOST , ssl-key-HOST , ssl-key
8321 \*(OP Variable chain that sets the file name for the private key of
8322 a SSL/TLS client certificate.
8323 If unset, the name of the certificate file is used.
8324 The file is expected to be in PEM format.
8325 This is a direct interface to the
8329 function of the OpenSSL library, if available.
8332 .It Va ssl-method-USER@HOST , ssl-method-HOST , ssl-method
8333 \*(OB\*(OP Please use the newer and more flexible
8335 instead: if both values are set,
8337 will take precedence!
8338 Can be set to the following values, the actually used
8340 specification to which it is mapped is shown in parenthesis:
8342 .Pf ( Ql -ALL, TLSv1.2 ) ,
8344 .Pf ( Ql -ALL, TLSv1.1 ) ,
8346 .Pf ( Ql -ALL, TLSv1 )
8349 .Pf ( Ql -ALL, SSLv3 ) ;
8354 and thus includes the SSLv3 protocol.
8355 Note that SSLv2 is no longer supported at all.
8358 .It Va ssl-no-default-ca
8359 \*(BO\*(OP Don't load default CA locations to verify SSL/TLS server
8363 .It Va ssl-protocol-USER@HOST , ssl-protocol-HOST , ssl-protocol
8364 \*(OP Specify the used SSL/TLS protocol.
8365 This is a direct interface to the
8369 function of the OpenSSL library, if available;
8370 otherwise an \*(UA internal parser is used which understands the
8371 following subset of (case-insensitive) command strings:
8377 as well as the special value
8379 Multiple specifications may be given via a comma-separated list which
8380 ignores any whitespace.
8383 plus prefix will enable a protocol, a
8385 minus prefix will disable it, so that
8387 will enable only the TLSv1.2 protocol.
8389 It depends upon the used TLS/SSL library which protocols are actually
8390 supported and which protocols are used if
8392 is not set, but note that SSLv2 is no longer supported at all and
8394 Especially for older protocols explicitly securing
8396 may be worthwile, see
8397 .Sx "An example configuration" .
8401 \*(OP Gives the pathname to an entropy daemon socket, see
8403 Not all SSL/TLS libraries support this.
8406 .It Va ssl-rand-file
8407 \*(OP Gives the filename to a file with random entropy data, see
8408 .Xr RAND_load_file 3 .
8409 If this variable is not set, or set to the empty string, or if the
8410 filename expansion failed, then
8411 .Xr RAND_file_name 3
8412 will be used to create the filename if, and only if,
8414 documents that the SSL PRNG is not yet sufficiently seeded.
8415 If \*(UA successfully seeded the SSL PRNG then it'll update the file via
8416 .Xr RAND_write_file 3 .
8417 This variable is only used if
8419 is not set (or not supported by the SSL/TLS library).
8422 .It Va ssl-verify-USER@HOST , ssl-verify-HOST , ssl-verify
8423 \*(OP Variable chain that sets the action to be performed if an error
8424 occurs during SSL/TLS server certificate validation.
8425 Valid (case-insensitive) values are
8427 (fail and close connection immediately),
8429 (ask whether to continue on standard input),
8431 (show a warning and continue),
8433 (do not perform validation).
8439 If only set without an assigned value, then this option inhibits the
8444 header fields that include obvious references to \*(UA.
8445 There are two pitfalls associated with this:
8446 First, the message id of outgoing messages is not known anymore.
8447 Second, an expert may still use the remaining information in the header
8448 to track down the originating mail user agent.
8453 suppression doesn't occur.
8458 (\*(OP) This specifies a comma-separated list of
8463 .Sx "On terminal control and line editor" ,
8464 escape commas with reverse solidus) to be used to overwrite or define
8466 Note that this variable will only be queried once at program startup and
8467 can thus only be specified in resource files or on the command line.
8470 String capabilities form
8472 pairs and are expected unless noted otherwise.
8473 Numerics have to be notated as
8475 where the number is expected in normal decimal notation.
8476 Finally, booleans don't have any value but indicate a true or false
8477 state simply by being defined or not; this indeed means that \*(UA
8478 doesn't support undefining an existing boolean.
8479 String capability values will undergo some expansions before use:
8480 for one notations like
8483 .Ql control-LETTER ,
8484 and for clarification purposes
8486 can be used to specify
8488 (the control notation
8490 could lead to misreadings when a left bracket follows, which it does for
8491 the standard CSI sequence);
8492 finally three letter octal sequences, as in
8495 To specify that a terminal supports 256-colours, and to define sequences
8496 that home the cursor and produce an audible bell, one might write:
8498 .Bd -literal -offset indent
8499 set termcap='Co#256,home=\eE[H,bel=^G'
8503 The following terminal capabilities are or may be meaningful for the
8504 operation of the builtin line editor or \*(UA in general:
8507 .Bl -tag -compact -width yay
8509 .It Cd colors Ns \0or Cd Co
8511 numeric capability specifying the maximum number of colours.
8512 Note that \*(UA doesn't actually care about the terminal beside that,
8513 but always emits ANSI / ISO 6429 escape sequences.
8516 .It Cd rmcup Ns \0or Cd te Ns \0/ Cd smcup Ns \0or Cd ti
8520 respectively: exit and enter the alternative screen
8522 effectively turning \*(UA into a fullscreen application.
8523 To disable that, set (at least) one to the empty string.
8525 .It Cd smkx Ns \0or Cd ks Ns \0/ Cd rmkx Ns \0or Cd ke
8529 respectively: enable and disable the keypad.
8530 This is always enabled if available, because it seems even keyboards
8531 without keypads generate other key codes for, e.g., cursor keys in that
8532 case, and only if enabled we see the codes that we are interested in.
8534 .It Cd ed Ns \0or Cd cd
8538 .It Cd clear Ns \0or Cd cl
8540 clear the screen and home cursor.
8541 (Will be simulated via
8546 .It Cd home Ns \0or Cd ho
8551 .It Cd el Ns \0or Cd ce
8553 clear to the end of line.
8554 (Will be simulated via
8556 plus repetitions of space characters.)
8558 .It Cd hpa Ns \0or Cd ch
8559 .Cd column_address :
8560 move the cursor (to the given column parameter) in the current row.
8561 (Will be simulated via
8567 .Cd carriage_return :
8568 move to the first column in the current row.
8569 The default builtin fallback is
8572 .It Cd cub1 Ns \0or Cd le
8574 move the cursor left one space (non-destructively).
8575 The default builtin fallback is
8578 .It Cd cuf1 Ns \0or Cd nd
8580 move the cursor right one space (non-destructively).
8581 The default builtin fallback is
8583 which is used by most terminals.
8591 Many more capabilities which describe key-sequences are documented for
8595 .It Va termcap-disable
8596 \*(OP Disable any interaction with a terminal control library.
8597 If set only some generic fallback builtins and possibly the content of
8599 describe the terminal to \*(UA.
8601 that this variable will only be queried once at program startup and can
8602 thus only be specified in resource files or on the command line.
8606 If defined, gives the number of lines of a message to be displayed
8609 if unset, the first five lines are printed, if set to 0 the variable
8612 If the value is negative then its absolute value will be used for right
8615 height; (shifting bitwise is like dividing algorithmically, but since
8616 it takes away bits the value decreases pretty fast).
8620 \*(BO If set then the
8622 command series will strip adjacent empty lines and quotations.
8626 The character set of the terminal \*(UA operates on,
8627 and the one and only supported character set that \*(UA can use if no
8628 character set conversion capabilities have been compiled into it,
8629 in which case it defaults to ISO-8859-1 unless it can deduce a value
8633 Refer to the section
8634 .Sx "Character sets"
8635 for the complete picture about character sets.
8639 For a safety-by-default policy \*(UA sets its process
8643 but this variable can be used to override that:
8644 set it to an empty value to don't change the (current) setting,
8645 otherwise the process file mode creation mask is updated to the new value.
8646 Child processes inherit the process file mode creation mask.
8649 .It Va user-HOST , user
8650 \*(IN Variable chain that sets a global fallback user name, which is
8651 used in case none has been given in the protocol and account-specific
8653 This variable defaults to the name of the user who runs \*(UA.
8657 \*(BO Setting this option enables upward compatibility with \*(UA
8658 version 15.0 in respect to which configuration options are available and
8659 how they are handled.
8660 This manual uses \*(IN and \*(OU to refer to the new and the old way of
8661 doing things, respectively.
8665 \*(BO Setting this option, also controllable via the command line option
8667 causes \*(UA to be more verbose, e.g., it will display obsoletion
8668 warnings and SSL/TLS certificate chains.
8669 Even though marked \*(BO this option may be set twice in order to
8670 increase the level of verbosity even more, in which case even details of
8671 the actual message delivery and protocol conversations are shown.
8674 is sufficient to disable verbosity as such.
8680 .It Va version , version-major , version-minor , version-update
8681 \*(RO \*(UA version information: the first variable contains a string
8682 containing the complete version identification, the latter three contain
8683 only digits: the major, minor and update version numbers.
8684 The output of the command
8686 will include this information.
8689 .It Va writebackedited
8690 If this variable is set messages modified using the
8694 commands are written back to the current folder when it is quit;
8695 it is only honoured for writable folders in MBOX format, though.
8696 Note that the editor will be pointed to the raw message content in that
8697 case, i.e., neither MIME decoding nor decryption will have been
8698 performed, and proper RFC 4155
8700 quoting of newly added or edited content is also left as an excercise to
8704 .\" }}} (INTERNAL VARIABLES)
8707 .\" .Sh ENVIRONMENT {{{
8711 .Dq environment variable
8712 should be considered an indication that these variables are either
8713 standardized as vivid parts of process environments, or that they are
8714 commonly found in there.
8715 The process environment is inherited from the
8717 once \*(UA is started, and unless otherwise explicitly noted handling of
8718 the following variables transparently integrates into that of the
8719 .Sx "INTERNAL VARIABLES"
8720 from \*(UA's point of view.
8721 This means that, e.g., they can be managed via
8725 causing automatic program environment updates (to be inherited by
8726 newly created child processes).
8729 In order to transparently integrate other environment variables equally
8730 they need to be imported (linked) with the command
8732 This command can also be used to set and unset non-integrated
8733 environment variables from scratch, sufficient system support provided.
8734 The following example, applicable to a POSIX shell, sets the
8736 environment variable for \*(UA only, and beforehand exports the
8738 in order to affect any further processing in the running shell:
8740 .Bd -literal -offset indent
8741 $ EDITOR="vim -u ${HOME}/.vimrc"
8743 $ COLUMNS=80 \*(uA -R
8746 .Bl -tag -width ".It Ev _AILR_"
8749 The user's preferred width in column positions for the terminal screen
8751 Queried and used once on program startup, actively managed for child
8752 processes and the MLE (see
8753 .Sx "On terminal control and line editor" )
8754 in interactive mode thereafter.
8758 The name of the (mailbox)
8760 to use for saving aborted messages if
8762 is set; this defaults to
8769 is set no output will be generated, otherwise the contents of the file
8774 Pathname of the text editor to use in the
8778 .Sx "TILDE ESCAPES" .
8779 A default editor is used if this value is not defined.
8783 The user's home directory.
8784 This variable is only used when it resides in the process environment.
8791 .It Ev LANG , LC_ALL , LC_COLLATE , LC_CTYPE , LC_MESSAGES
8795 .Sx "Character sets" .
8796 (Only recognized by the system in the process environment.)
8800 The user's preferred number of lines on a page or the vertical screen
8801 or window size in lines.
8802 Queried and used once on program startup, actively managed for child
8803 processes in interactive mode thereafter.
8807 Pathname of the directory lister to use in the
8809 command when operating on local mailboxes.
8812 (path search through
8817 Upon startup \*(UA will actively ensure that this variable refers to the
8818 name of the user who runs \*(UA, in order to be able to pass a verified
8819 name to any newly created child process.
8823 Is used as the user's primary system mailbox, if set.
8824 Otherwise, a system-dependent default is used.
8825 Supports the special syntax conventions that are documented for the
8831 \*(OP Overrides the default path search for
8832 .Sx "The Mailcap files" ,
8833 which is defined in the standard RFC 1524 as
8834 .Ql ~/.mailcap:\:/etc/mailcap:\:/usr/etc/mailcap:\:/usr/local/etc/mailcap .
8835 .\" TODO we should have a mailcaps-default virtual RDONLY option!
8836 (\*(UA makes it a configuration option, however.)
8837 Note this is not a search path, but a path search.
8841 Is used as a startup file instead of
8844 When \*(UA scripts are invoked on behalf of other users,
8845 either this variable should be set to
8849 command line option should be used in order to avoid side-effects from
8850 reading their configuration files.
8851 This variable is only used when it resides in the process environment.
8855 The name of the user's mbox file.
8856 A logical subset of the special conventions that are documented for the
8861 The fallback default is
8866 Traditionally this secondary mailbox is used as the file to save
8867 messages from the primary system mailbox that have been read.
8869 .Sx "Message states" .
8872 .It Ev NAIL_NO_SYSTEM_RC
8873 If this variable is set then reading of
8875 at startup is inhibited, i.e., the same effect is achieved as if \*(UA
8876 had been started up with the option
8878 This variable is only used when it resides in the process environment.
8882 \*(IN\*(OP This variable overrides the default location of the user's
8888 Pathname of the program to use for backing the command
8892 variable enforces usage of a pager for output.
8893 The default paginator is
8895 (path search through
8898 \*(UA inspects the contents of this variable: if its contains the string
8900 then a non-existing environment variable
8907 dependent on whether terminal control support is available and whether
8908 that supports full (alternative) screen mode or not (also see
8909 .Sx "On terminal control and line editor" ) .
8913 will optionally be set to
8920 A list of directories that is searched by the shell when looking for
8921 commands (as such only recognized in the process environment).
8925 The shell to use for the commands
8931 and when starting subprocesses.
8932 A default shell is used if this option is not defined.
8935 .It Ev SOURCE_DATE_EPOCH
8936 If set, this specifies a time in seconds since the Unix epoch
8937 (1970-01-01) to be used in place of the current time.
8938 This is for the sake of reproduceability of tests, to be used during
8939 development or by software packagers.
8943 \*(OP The terminal type for which output is to be prepared.
8944 For extended colour and font control please refer to
8945 .Sx "Coloured display" ,
8946 and for terminal management in general to
8947 .Sx "On terminal control and line editor" .
8951 Used as directory for temporary files instead of
8954 This variable is only used when it resides in the process environment.
8960 (see there), but this variable is not standardized, should therefore not
8961 be used, and is only corrected if already set.
8965 Pathname of the text editor to use in the
8969 .Sx "TILDE ESCAPES" .
8977 .Bl -tag -width ".It Pa _etc/mime.type_"
8979 File giving initial commands.
8982 System wide initialization file.
8986 \*(OP Personal MIME type handler definition file, see
8987 .Sx "The Mailcap files" .
8988 (RFC 1524 location, the actual path is a configuration option.)
8992 \*(OP System wide MIME type handler definition file, see
8993 .Sx "The Mailcap files" .
8994 (RFC 1524 location, the actual path is a configuration option.)
8997 .It Pa ~/.mime.types
8998 Personal MIME types, see
8999 .Sx "The mime.types files" .
9002 .It Pa /etc/mime.types
9003 System wide MIME types, see
9004 .Sx "The mime.types files" .
9008 \*(IN\*(OP The default location of the users
9010 file \(en the section
9011 .Sx "The .netrc file"
9012 documents the file format.
9015 .\" .Ss "The mime.types files" {{{
9016 .Ss "The mime.types files"
9018 When sending messages \*(UA tries to determine the content type of all
9020 When displaying message content or attachments \*(UA uses the content
9021 type to decide whether it can directly display data or whether it needs
9022 to deal with content handlers.
9023 It learns about MIME types and how to treat them by reading
9025 files, the loading of which can be controlled by setting the variable
9026 .Va mimetypes-load-control .
9029 can also be used to deal with MIME types.)
9031 files have the following syntax:
9034 .Dl type/subtype extension [extension ...]
9039 are strings describing the file contents, and one or multiple
9041 s, separated by whitespace, name the part of a filename starting after
9042 the last dot (of interest).
9043 Comments may be introduced anywhere on a line with a number sign
9045 causing the remaining line to be discarded.
9047 \*(UA also supports an extended, non-portable syntax in specially
9048 crafted files, which can be loaded via the alternative value syntax of
9049 .Va mimetypes-load-control
9050 and prepends an optional
9054 .Dl [type-marker ]type/subtype extension [extension ...]
9057 The following type markers are supported:
9060 .Bl -tag -compact -offset indent -width ".It Ar _n_u"
9062 Treat message parts with this content as plain text.
9067 Treat message parts with this content as HTML tagsoup.
9068 If the \*(OPal HTML-tagsoup-to-text converter is not available treat
9069 the content as plain text instead.
9073 but instead of falling back to plain text require an explicit content
9074 handler to be defined.
9079 for sending messages:
9081 .Va mime-allow-text-controls ,
9082 .Va mimetypes-load-control .
9083 For reading etc. messages:
9084 .Sx "HTML mail and MIME attachments" ,
9085 .Sx "The Mailcap files" ,
9087 .Va mime-counter-evidence ,
9088 .Va mimetypes-load-control ,
9089 .Va pipe-TYPE/SUBTYPE ,
9090 .Va pipe-EXTENSION .
9093 .\" .Ss "The Mailcap files" {{{
9094 .Ss "The Mailcap files"
9097 .Dq User Agent Configuration Mechanism
9098 which \*(UA \*(OPally supports.
9099 It defines a file format to be used to inform mail user agent programs
9100 about the locally-installed facilities for handling various data
9101 formats, i.e., about commands and how they can be used to display, edit
9102 etc. MIME part contents, as well as a default path search that includes
9103 multiple possible locations of
9107 environment variable that can be used to overwrite that (repeating here
9108 that it is not a search path, but instead a path search specification).
9109 Any existing files will be loaded in sequence, appending any content to
9110 the list of MIME type handler directives.
9114 files consist of a set of newline separated entries.
9115 Comment lines start with a number sign
9117 (in the first column!) and are ignored.
9118 Empty lines are also ignored.
9119 All other lines form individual entries that must adhere to the syntax
9121 To extend a single entry (not comment) its line can be continued on
9122 follow lines if newline characters are
9124 by preceding them with the reverse solidus character
9126 The standard doesn't specify how leading whitespace of follow lines is
9127 to be treated, therefore \*(UA retains it.
9131 entries consist of a number of semicolon
9133 separated fields, and the reverse solidus
9135 character can be used to escape any following character including
9136 semicolon and itself.
9137 The first two fields are mandatory and must occur in the specified
9138 order, the remaining fields are optional and may appear in any order.
9139 Leading and trailing whitespace of content is ignored (removed).
9142 The first field defines the MIME
9144 the entry is about to handle (case-insensitively, and no reverse solidus
9145 escaping is possible in this field).
9146 If the subtype is specified as an asterisk
9148 the entry is meant to match all subtypes of the named type, e.g.,
9150 would match any audio type.
9151 The second field defines the shell command which shall be used to
9153 MIME parts of the given type; it is implicitly called the
9160 shell commands message (MIME part) data is passed via standard input
9161 unless the given shell command includes one or more instances of the
9164 in which case these instances will be replaced with a temporary filename
9165 and the data will have been stored in the file that is being pointed to.
9168 shell commands data is assumed to be generated on standard output unless
9169 the given command includes (one ore multiple)
9171 In any case any given
9173 format is replaced with a(n already) properly quoted filename.
9174 Note that when a command makes use of a temporary file via
9176 then \*(UA will remove it again, as if the
9177 .Cd x-mailx-tmpfile ,
9178 .Cd x-mailx-tmpfile-fill
9180 .Cd x-mailx-tmpfile-unlink
9181 flags had been set; see below for more.
9184 The optional fields either define a shell command or an attribute (flag)
9185 value, the latter being a single word and the former being a keyword
9186 naming the field followed by an equals sign
9188 succeeded by a shell command, and as usual for any
9190 content any whitespace surrounding the equals sign will be removed, too.
9191 Optional fields include the following:
9194 .Bl -tag -width textualnewlines
9196 A program that can be used to compose a new body or body part in the
9203 field, but is to be used when the composing program needs to specify the
9205 header field to be applied to the composed data.
9209 A program that can be used to edit a body or body part in the given
9214 A program that can be used to print a message or body part in the given
9219 Specifies a program to be run to test some condition, e.g., the machine
9220 architecture, or the window system in use, to determine whether or not
9221 this mailcap entry applies.
9222 If the test fails, a subsequent mailcap entry should be sought; also see
9223 .Cd x-mailx-test-once .
9225 .It Cd needsterminal
9226 This flag field indicates that the given shell command must be run on
9227 an interactive terminal.
9228 \*(UA will temporarily release the terminal to the given command in
9229 interactive mode, in non-interactive mode this entry will be entirely
9230 ignored; this flag implies
9231 .Cd x-mailx-noquote .
9233 .It Cd copiousoutput
9234 A flag field which indicates that the output of the
9236 command will be an extended stream of textual output that can be
9237 (re)integrated into \*(UA's normal visual display.
9238 It is mutually exclusive with
9241 .Cd x-mailx-always .
9243 .It Cd textualnewlines
9244 A flag field which indicates that this type of data is line-oriented and
9247 all newlines should be converted to canonical form (CRLF) before
9248 encoding, and will be in that form after decoding.
9252 This field gives a file name format, in which
9254 will be replaced by a random string, the joined combination of which
9255 will be used as the filename denoted by
9256 .Ev NAIL_FILENAME_TEMPORARY .
9257 One could specify that a GIF file being passed to an image viewer should
9258 have a name ending in
9261 .Ql nametemplate=%s.gif .
9262 Note that \*(UA ignores the name template unless that solely specifies
9263 a filename suffix that consists of (ASCII) alphabetic and numeric
9264 characters, the underscore and dot only.
9267 Names a file, in X11 bitmap (xbm) format, which points to an appropriate
9268 icon to be used to visually denote the presence of this kind of data.
9269 This field is not used by \*(UA.
9272 A textual description that describes this type of data.
9274 .It Cd x-mailx-always
9275 Extension flag field that denotes that the given
9277 command shall be executed even if multiple messages will be displayed
9279 Normally messages which require external viewers that produce output
9280 which doesn't integrate into \*(UA's visual display (i.e., don't have
9282 set) have to be addressed directly and individually.
9283 (To avoid cases where, e.g., a thousand PDF viewer instances are spawned
9286 .It Cd x-mailx-even-if-not-interactive
9287 An extension flag test field \(em by default handlers without
9289 are entirely ignored in non-interactive mode, but if this flag is set
9290 then their use will be considered.
9291 It is an error if this flag is set for commands that use the flag
9294 .It Cd x-mailx-noquote
9295 An extension flag field that indicates that even a
9298 command shall not be used to generate message quotes
9299 (as it would be by default).
9301 .It Cd x-mailx-async
9302 Extension flag field that denotes that the given
9304 command shall be executed asynchronously, without blocking \*(UA.
9305 Cannot be used in conjunction with
9308 .It Cd x-mailx-test-once
9309 Extension flag which denotes whether the given
9311 command shall be evaluated once only and the (boolean) result be cached.
9312 This is handy if some global unchanging condition is to be queried, like
9313 .Dq running under the X Window System .
9315 .It Cd x-mailx-tmpfile
9316 Extension flag field that requests creation of a zero-sized temporary
9317 file, the name of which is to be placed in the environment variable
9318 .Ev NAIL_FILENAME_TEMPORARY .
9319 It is an error to use this flag with commands that include a
9323 .It Cd x-mailx-tmpfile-fill
9324 Normally the MIME part content is passed to the handler via standard
9325 input; if this flag is set then the data will instead be written into
9327 .Cd x-mailx-tmpfile .
9328 In order to cause deletion of the temporary file you will have to set
9329 .Cd x-mailx-tmpfile-unlink
9331 It is an error to use this flag with commands that include a
9335 .It Cd x-mailx-tmpfile-unlink
9336 Extension flag field that requests that the temporary file shall be
9337 deleted automatically when the command loop is entered again at latest.
9338 (Don't use this for asynchronous handlers.)
9339 It is an error to use this flag with commands that include a
9341 format, or without also setting
9344 .Cd x-mailx-tmpfile-fill .
9346 .It Cd x-mailx-tmpfile-keep
9349 implies the three tmpfile related flags above, but if you want, e.g.,
9351 and deal with the temporary file yourself, you can add in this flag to
9353 .Cd x-mailx-tmpfile-unlink .
9358 The standard includes the possibility to define any number of additional
9359 entry fields, prefixed by
9361 Flag fields apply to the entire
9363 entry \(em in some unusual cases, this may not be desirable, but
9364 differentiation can be accomplished via separate entries, taking
9365 advantage of the fact that subsequent entries are searched if an earlier
9366 one does not provide enough information.
9369 command needs to specify the
9373 command shall not, the following will help out the latter (with enabled
9377 level \*(UA will show information about handler evaluation):
9379 .Bd -literal -offset indent
9380 application/postscript; ps-to-terminal %s; needsterminal
9381 application/postscript; ps-to-terminal %s; compose=idraw %s
9385 In fields any occurrence of the format string
9387 will be replaced by the
9390 Named parameters from the
9392 field may be placed in the command execution line using
9394 followed by the parameter name and a closing
9397 The entire parameter should appear as a single command line argument,
9398 regardless of embedded spaces; thus:
9400 .Bd -literal -offset indent
9402 Content-type: multipart/mixed; boundary=42
9405 multipart/*; /usr/local/bin/showmulti \e
9406 %t %{boundary} ; composetyped = /usr/local/bin/makemulti
9408 # Executed shell command
9409 /usr/local/bin/showmulti multipart/mixed 42
9413 .\" TODO v15: Mailcap: %n,%F
9414 Note that \*(UA doesn't support handlers for multipart MIME parts as
9415 shown in this example (as of today).
9416 \*(UA doesn't support the additional formats
9420 An example file, also showing how to properly deal with the expansion of
9422 which includes any quotes that are necessary to make it a valid shell
9423 argument by itself and thus will cause undesired behaviour when placed
9424 in additional user-provided quotes:
9426 .Bd -literal -offset indent
9428 text/richtext; richtext %s; copiousoutput
9430 text/x-perl; perl -cWT %s
9434 trap "rm -f ${infile}" EXIT\e; \e
9435 trap "exit 75" INT QUIT TERM\e; \e
9437 x-mailx-async; x-mailx-tmpfile-keep
9439 application/*; echo "This is \e"%t\e" but \e
9440 is 50 \e% Greek to me" \e; < %s head -c 1024 | cat -vET; \e
9441 copiousoutput; x-mailx-noquote
9446 .Sx "HTML mail and MIME attachments" ,
9447 .Sx "The mime.types files" ,
9450 .Va mime-counter-evidence ,
9451 .Va pipe-TYPE/SUBTYPE ,
9452 .Va pipe-EXTENSION .
9455 .\" .Ss "The .netrc file" {{{
9456 .Ss "The .netrc file"
9460 file contains user credentials for machine accounts.
9461 The default location in the user's
9463 directory may be overridden by the
9465 environment variable.
9466 The file consists of space, tabulator or newline separated tokens.
9467 \*(UA implements a parser that supports a superset of the original BSD
9468 syntax, but users should nonetheless be aware of portability glitches
9469 of that file format, shall their
9471 be usable across multiple programs and platforms:
9474 .Bl -bullet -compact
9476 BSD doesn't support single, but only double quotation marks, e.g.,
9477 .Ql password="pass with spaces" .
9479 BSD (only?) supports escaping of single characters via a reverse solidus
9480 (e.g., a space can be escaped via
9482 in- as well as outside of a quoted string.
9484 BSD doesn't require the final quotation mark of the final user input token.
9486 The original BSD (Berknet) parser also supported a format which allowed
9487 tokens to be separated with commas \(en whereas at least Hewlett-Packard
9488 still seems to support this syntax, \*(UA does not!
9490 As a non-portable extension some widely-used programs support
9491 shell-style comments: if an input line starts, after any amount of
9492 whitespace, with a number sign
9494 then the rest of the line is ignored.
9496 Whereas other programs may require that the
9498 file is accessible by only the user if it contains a
9504 \*(UA will always require these strict permissions.
9508 Of the following list of supported tokens \*(UA only uses (and caches)
9513 At runtime the command
9515 can be used to control \*(UA's
9519 .Bl -tag -width password
9520 .It Cd machine Ar name
9521 The hostname of the entries' machine, lowercase-normalized by \*(UA
9523 Any further file content, until either end-of-file or the occurrence
9528 first-class token is bound (only related) to the machine
9531 As an extension that shouldn't be the cause of any worries
9532 \*(UA supports a single wildcard prefix for
9534 .Bd -literal -offset indent
9535 machine *.example.com login USER password PASS
9536 machine pop3.example.com login USER password PASS
9537 machine smtp.example.com login USER password PASS
9543 .Ql pop3.example.com ,
9547 .Ql local.smtp.example.com .
9548 Note that in the example neither
9549 .Ql pop3.example.com
9551 .Ql smtp.example.com
9552 will be matched by the wildcard, since the exact matches take
9553 precedence (it is however faster to specify it the other way around).
9558 except that it is a fallback entry that is used shall none of the
9559 specified machines match; only one default token may be specified,
9560 and it must be the last first-class token.
9562 .It Cd login Ar name
9563 The user name on the remote machine.
9565 .It Cd password Ar string
9566 The user's password on the remote machine.
9568 .It Cd account Ar string
9569 Supply an additional account password.
9570 This is merely for FTP purposes.
9572 .It Cd macdef Ar name
9574 A macro is defined with the specified
9576 it is formed from all lines beginning with the next line and continuing
9577 until a blank line is (consecutive newline characters are) encountered.
9580 entries cannot be utilized by multiple machines, too, but must be
9581 defined following the
9583 they are intended to be used with.)
9586 exists, it is automatically run as the last step of the login process.
9587 This is merely for FTP purposes.
9594 .\" .Sh EXAMPLES {{{
9597 .\" .Ss "An example configuration" {{{
9598 .Ss "An example configuration"
9600 .Bd -literal -offset indent
9601 # This example assumes v15.0 compatibility mode
9604 # Where are the up-to-date SSL certificates?
9605 #set ssl-ca-dir=/etc/ssl/certs
9606 set ssl-ca-file=/etc/ssl/certs/ca-certificates.crt
9608 # (Since we manage up-to-date ones explicitly, don't use any,
9609 # possibly outdated, default certificates shipped with OpenSSL)
9610 set ssl-no-default-ca
9612 # Don't use protocols older than TLS v1.2.
9613 # Change this only when the remote server doesn't support it:
9614 # maybe use ssl-protocol-HOST (or -USER@HOST) syntax to define
9615 # such explicit exceptions, then
9616 set ssl-protocol='-ALL,+TLSv1.2'
9618 # Explicitly define the list of ciphers, which may improve security,
9619 # especially with protocols older than TLS v1.2. See ciphers(1).
9620 # Including "@STRENGTH" will sort the final list by algorithm strength.
9621 # In reality it is possibly best to only use ssl-cipher-list-HOST
9622 # (or -USER@HOST), as necessary, again..
9623 set ssl-cipher-list=TLSv1.2:!aNULL:!eNULL:!MEDIUM:!LOW:!EXPORT:@STRENGTH
9624 # ALL:!aNULL:!MEDIUM:!LOW:!MD5:!RC4:!EXPORT:@STRENGTH
9626 # Request strict transport security checks!
9627 set ssl-verify=strict
9629 # Essential setting: select allowed character sets
9630 set sendcharsets=utf-8,iso-8859-1
9632 # A very kind option: when replying to a message, first try to
9633 # use the same encoding that the original poster used herself!
9634 set reply-in-same-charset
9636 # When replying to or forwarding a message the comment and name
9637 # parts of email addresses are removed unless this variable is set
9640 # When sending messages, wait until the Mail-Transfer-Agent finishs.
9641 # Only like this you'll be able to see errors reported through the
9642 # exit status of the MTA (including the builtin SMTP one)!
9645 # Only use builtin MIME types, no mime.types(5) files
9646 set mimetypes-load-control
9648 # Default directory where we act in (relative to $HOME)
9650 # A leading "+" (often) means: under *folder*
9651 # *record* is used to save copies of sent messages
9652 set MBOX=+mbox.mbox record=+sent.mbox DEAD=+dead.txt
9654 # Make "file mymbox" and "file myrec" go to..
9655 shortcut mymbox %:+mbox.mbox myrec +sent.mbox
9657 # Not really optional, e.g., for S/MIME
9658 set from='Your Name <address@exam.ple>'
9660 # It may be necessary to set hostname and/or smtp-hostname
9661 # if the "SERVER" of mta and "domain" of from don't match.
9662 # The `urlencode' command can be used to encode USER and PASS
9663 set mta=(smtps?|submission)://[USER[:PASS]@]SERVER[:PORT] \e
9664 smtp-auth=login/plain... \e
9667 # Never refuse to start into interactive mode, and more
9669 colour-pager crt= \e
9670 followup-to followup-to-honour=ask-yes \e
9671 history-file=+.\*(uAhist history-size=-1 history-gabby \e
9672 mime-counter-evidence=0xE \e
9673 prompt='?\e?[\e$ \e@]\e& ' \e
9674 reply-to-honour=ask-yes \e
9677 # When `t'yping messages, show only these headers
9678 # (use `T'ype for all headers and `S'how for raw message)
9679 retain date from to cc subject
9681 # Some mailing lists
9682 mlist '@xyz-editor\e.xyz$' '@xyzf\e.xyz$'
9683 mlsubscribe '^xfans@xfans\e.xyz$'
9685 # A real life example of a very huge free mail provider
9687 set folder=~/spool/XooglX MAIL=+syste.mbox sent=+sent
9688 set from='Your Name <address@examp.ple>'
9689 set mta=smtp://USER:PASS@smtp.gmXil.com smtp-use-starttls
9692 # Here is a pretty large one which does not allow sending mails
9693 # if there is a domain name mismatch on the SMTP protocol level,
9694 # which would bite us if the value of from does not match, e.g.,
9695 # for people who have a sXXXXeforge project and want to speak
9696 # with the mailing list under their project account (in from),
9697 # still sending the message through their normal mail provider
9699 set folder=~/spool/XandeX MAIL=+syste.mbox sent=+sent
9700 set from='Your Name <address@exam.ple>'
9701 set mta=smtps://USER:PASS@smtp.yaXXex.ru:465 \e
9702 hostname=yaXXex.com smtp-hostname=
9705 # Create some new commands so that, e.g., `ls /tmp' will..
9706 wysh ghost lls '!ls ${LS_COLOR_FLAG} -aFlrS'
9707 wysh ghost llS '!ls ${LS_COLOR_FLAG} -aFlS'
9708 wysh ghost ls '!ls ${LS_COLOR_FLAG} -aFrS'
9709 wysh ghost lS '!ls ${LS_COLOR_FLAG} -aFS'
9710 wysh ghost lla '!ls ${LS_COLOR_FLAG} -aFlr'
9711 wysh ghost llA '!ls ${LS_COLOR_FLAG} -aFl'
9712 wysh ghost la '!ls ${LS_COLOR_FLAG} -aFr'
9713 wysh ghost lA '!ls ${LS_COLOR_FLAG} -aF'
9714 wysh ghost ll '!ls ${LS_COLOR_FLAG} -aFltr'
9715 wysh ghost lL '!ls ${LS_COLOR_FLAG} -aFlt'
9716 wysh ghost l '!ls ${LS_COLOR_FLAG} -aFtr'
9717 wysh ghost L '!ls ${LS_COLOR_FLAG} -aFt'
9719 # We don't support gpg(1) directly yet. But simple --clearsign'd
9720 # message parts can be dealt with as follows:
9722 wysh set pipe-text/plain=$'@*#++=@\e
9723 < "${NAIL_FILENAME_TEMPORARY}" awk \e
9724 -v TMPFILE="${NAIL_FILENAME_TEMPORARY}" \e'\e
9726 /^-----BEGIN PGP SIGNED MESSAGE-----/,/^$/{\e
9729 print "--- GPG --verify ---";\e
9730 system("gpg --verify " TMPFILE " 2>&1");\e
9731 print "--- GPG --verify ---";\e
9735 /^-----BEGIN PGP SIGNATURE-----/,\e
9736 /^-----END PGP SIGNATURE-----/{\e
9746 !printf 'Key IDs to gpg --recv-keys: ';\e
9748 gpg --recv-keys ${keyids};
9754 When storing passwords in
9756 appropriate permissions should be set on this file with
9757 .Ql $ chmod 0600 \*(ur .
9760 is available user credentials can be stored in the central
9762 file instead; e.g., here is a different version of the example account
9763 that sets up SMTP and POP3:
9765 .Bd -literal -offset indent
9767 set folder=~/spool/XandeX MAIL=+syste.mbox sent=+sent
9768 set from='Your Name <address@exam.ple>'
9770 # Load an encrypted ~/.netrc by uncommenting the next line
9771 #set netrc-pipe='gpg -qd ~/.netrc.pgp'
9773 set mta=smtps://smtp.yXXXXx.ru:465 \e
9774 smtp-hostname= hostname=yXXXXx.com
9775 set pop3-keepalive=240 pop3-no-apop-pop.yXXXXx.ru
9776 ghost xp fi pop3s://pop.yXXXXx.ru
9785 .Bd -literal -offset indent
9786 machine *.yXXXXx.ru login USER password PASS
9790 This configuration should now work just fine:
9793 .Dl $ echo text | \*(uA -vv -AXandeX -s Subject user@exam.ple
9796 .\" .Ss "Signed and encrypted messages with S/MIME" {{{
9797 .Ss "Signed and encrypted messages with S/MIME"
9799 \*(OP S/MIME provides two central mechanisms:
9800 message signing and message encryption.
9801 A signed message contains some data in addition to the regular text.
9802 The data can be used to verify that the message was sent using a valid
9803 certificate, that the sender's address in the message header matches
9804 that in the certificate, and that the message text has not been altered.
9805 Signing a message does not change its regular text;
9806 it can be read regardless of whether the recipient's software is able to
9810 It is thus usually possible to sign all outgoing messages if so desired.
9811 Encryption, in contrast, makes the message text invisible for all people
9812 except those who have access to the secret decryption key.
9813 To encrypt a message, the specific recipient's public encryption key
9815 It is therefore not possible to send encrypted mail to people unless their
9816 key has been retrieved from either previous communication or public key
9818 A message should always be signed before it is encrypted.
9819 Otherwise, it is still possible that the encrypted message text is
9823 A central concept to S/MIME is that of the certification authority (CA).
9824 A CA is a trusted institution that issues certificates.
9825 For each of these certificates it can be verified that it really
9826 originates from the CA, provided that the CA's own certificate is
9828 A set of CA certificates is usually delivered with OpenSSL and installed
9830 If you trust the source of your OpenSSL software installation,
9831 this offers reasonable security for S/MIME on the Internet.
9833 .Va ssl-no-default-ca
9837 .Va smime-ca-dir . )
9838 In general, a certificate cannot be more secure than the method its CA
9839 certificate has been retrieved with, though.
9840 Thus if you download a CA certificate from the Internet,
9841 you can only trust the messages you verify using that certificate as
9842 much as you trust the download process.
9845 The first thing you need for participating in S/MIME message exchange is
9846 your personal certificate, including a private key.
9847 The certificate contains public information, in particular your name and
9848 your email address(es), and the public key that is used by others to
9849 encrypt messages for you,
9850 and to verify signed messages they supposedly received from you.
9851 The certificate is included in each signed message you send.
9852 The private key must be kept secret.
9853 It is used to decrypt messages that were previously encrypted with your
9854 public key, and to sign messages.
9857 For personal use it is recommended that you get a S/MIME certificate
9858 from one of the major CAs on the Internet using your WWW browser.
9859 Many CAs offer such certificates for free.
9861 .Lk https://www.CAcert.org
9862 which issues client and server certificates to members of their
9863 community for free; their root certificate
9864 .Pf ( Lk https://\:www.cacert.org/\:certs/\:root.crt )
9865 is often not in the default set of trusted CA root certificates, though,
9866 which means you will have to download their root certificate separately
9867 and ensure it is part of our S/MIME certificate validation chain by
9870 or as a vivid member of the
9872 But let's take a step-by-step tour on how to setup S/MIME with
9873 a certificate from CAcert.org despite this situation!
9876 First of all you will have to become a member of the CAcert.org
9877 community, simply by registrating yourself via the web interface.
9878 Once you are, create and verify all email addresses you want to be able
9879 to create signed and encrypted messages for/with using the corresponding
9880 entries of the web interface.
9881 Now ready to create S/MIME certificates, so let's create a new
9882 .Dq client certificate ,
9883 ensure to include all email addresses that should be covered by the
9884 certificate in the following web form, and also to use your name as the
9888 Create a private key and a certificate request on your local computer
9889 (please see the manual pages of the used commands for more in-depth
9890 knowledge on what the used arguments etc. do):
9893 .Dl openssl req -nodes -newkey rsa:4096 -keyout key.pem -out creq.pem
9896 Afterwards copy-and-paste the content of
9898 into the certificate-request (CSR) field of the web form on the
9899 CAcert.org website (you may need to unfold some
9900 .Dq advanced options
9901 to see the corresponding text field).
9902 This last step will ensure that your private key (which never left your
9903 box) and the certificate belong together (through the public key that
9904 will find its way into the certificate via the certificate-request).
9905 You are now ready and can create your CAcert certified certificate.
9906 Download and store or copy-and-paste it as
9911 In order to use your new S/MIME setup you will have to create
9912 a combined private key/public key (certificate) file:
9915 .Dl cat key.pem pub.crt > ME@HERE.com.paired
9918 This is the file \*(UA will work with.
9919 If you have created your private key with a passphrase then \*(UA will
9920 ask you for it whenever a message is signed or decrypted.
9921 Set the following variables to henceforth use S/MIME (setting
9923 is of interest for verification only):
9925 .Bd -literal -offset indent
9926 set smime-ca-file=ALL-TRUSTED-ROOT-CERTS-HERE \e
9927 smime-sign-cert=ME@HERE.com.paired \e
9928 smime-sign-message-digest=SHA256 \e
9933 From each signed message you send, the recipient can fetch your
9934 certificate and use it to send encrypted mail back to you.
9935 Accordingly if somebody sends you a signed message, you can do the same,
9938 command to check the validity of the certificate.
9941 Variables of interest for S/MIME signing:
9945 .Va smime-crl-file ,
9946 .Va smime-no-default-ca ,
9948 .Va smime-sign-cert ,
9949 .Va smime-sign-include-certs
9951 .Va smime-sign-message-digest .
9954 After it has been verified save the certificate via
9956 and tell \*(UA that it should use it for encryption for further
9957 communication with that somebody:
9959 .Bd -literal -offset indent
9961 set smime-encrypt-USER@HOST=FILENAME \e
9962 smime-cipher-USER@HOST=AES256
9966 Additional variables of interest for S/MIME en- and decryption:
9969 .Va smime-encrypt-USER@HOST .
9972 You should carefully consider if you prefer to store encrypted messages
9974 If you do, anybody who has access to your mail folders can read them,
9975 but if you do not, you might be unable to read them yourself later if
9976 you happen to lose your private key.
9979 command saves messages in decrypted form, while the
9983 commands leave them encrypted.
9986 Note that neither S/MIME signing nor encryption applies to message
9987 subjects or other header fields yet.
9988 Thus they may not contain sensitive information for encrypted messages,
9989 and cannot be trusted even if the message content has been verified.
9990 When sending signed messages,
9991 it is recommended to repeat any important header information in the
9995 .\" .Ss "Using CRLs with S/MIME or SSL/TLS" {{{
9996 .Ss "Using CRLs with S/MIME or SSL/TLS"
9998 \*(OP Certification authorities (CAs) issue certificate revocation
9999 lists (CRLs) on a regular basis.
10000 These lists contain the serial numbers of certificates that have been
10001 declared invalid after they have been issued.
10002 Such usually happens because the private key for the certificate has
10004 because the owner of the certificate has left the organization that is
10005 mentioned in the certificate, etc.
10006 To seriously use S/MIME or SSL/TLS verification,
10007 an up-to-date CRL is required for each trusted CA.
10008 There is otherwise no method to distinguish between valid and
10009 invalidated certificates.
10010 \*(UA currently offers no mechanism to fetch CRLs, nor to access them on
10011 the Internet, so you have to retrieve them by some external mechanism.
10014 \*(UA accepts CRLs in PEM format only;
10015 CRLs in DER format must be converted, like, e.\|g.:
10018 .Dl $ openssl crl \-inform DER \-in crl.der \-out crl.pem
10021 To tell \*(UA about the CRLs, a directory that contains all CRL files
10022 (and no other files) must be created.
10027 variables, respectively, must then be set to point to that directory.
10028 After that, \*(UA requires a CRL to be present for each CA that is used
10029 to verify a certificate.
10032 .\" .Ss "Handling spam" {{{
10033 .Ss "Handling spam"
10035 \*(OP \*(UA can make use of several spam interfaces for the purpose of
10036 identification of, and, in general, dealing with spam messages.
10037 A precondition of most commands in order to function is that the
10039 variable is set to one of the supported interfaces.
10040 Once messages have been identified as spam their (volatile)
10042 state can be prompted: the
10046 message specifications will address respective messages and their
10048 entries will be used when displaying the
10050 in the header display.
10055 rates the given messages and sets their
10058 If the spam interface offers spam scores those can also be displayed in
10059 the header display by including the
10069 will interact with the Bayesian filter of the chosen interface and learn
10070 the given messages as
10074 respectively; the last command can be used to cause
10076 of messages; it adheres to their current
10078 state and thus reverts previous teachings.
10083 will simply set and clear, respectively, the mentioned volatile
10085 message flag, without any interface interaction.
10094 requires a running instance of the
10096 server in order to function, started with the option
10098 shall Bayesian filter learning be possible.
10100 .Bd -literal -offset indent
10101 $ spamd -i localhost:2142 -i /tmp/.spamsock -d [-L] [-l]
10102 $ spamd --listen=localhost:2142 --listen=/tmp/.spamsock \e
10103 --daemonize [--local] [--allow-tell]
10107 Thereafter \*(UA can make use of these interfaces:
10109 .Bd -literal -offset indent
10110 $ \*(uA -Sspam-interface=spamc -Sspam-maxsize=500000 \e
10111 -Sspamc-command=/usr/local/bin/spamc \e
10112 -Sspamc-arguments="-U /tmp/.spamsock" -Sspamc-user=
10114 $ \*(uA -Sspam-interface=spamc -Sspam-maxsize=500000 \e
10115 -Sspamc-command=/usr/local/bin/spamc \e
10116 -Sspamc-arguments="-d localhost -p 2142" -Sspamc-user=
10120 Using the generic filter approach allows usage of programs like
10122 Here is an example, requiring it to be accessible via
10125 .Bd -literal -offset indent
10126 $ \*(uA -Sspam-interface=filter -Sspam-maxsize=500000 \e
10127 -Sspamfilter-ham="bogofilter -n" \e
10128 -Sspamfilter-noham="bogofilter -N" \e
10129 -Sspamfilter-nospam="bogofilter -S" \e
10130 -Sspamfilter-rate="bogofilter -TTu 2>/dev/null" \e
10131 -Sspamfilter-spam="bogofilter -s" \e
10132 -Sspamfilter-rate-scanscore="1;^(.+)$"
10136 Because messages must exist on local storage in order to be scored (or
10137 used for Bayesian filter training), it is possibly a good idea to
10138 perform the local spam check last:
10140 .Bd -literal -offset indent
10141 define spamdelhook {
10143 spamset (header x-dcc-brand-metrics "bulk")
10144 # Server-side spamassassin(1)
10145 spamset (header x-spam-flag "YES")
10146 del :s # TODO we HAVE to be able to do `spamrate :u ! :sS'
10147 move :S +maybe-spam
10150 move :S +maybe-spam
10152 set folder-hook-FOLDER=spamdelhook
10156 See also the documentation for the variables
10157 .Va spam-interface , spam-maxsize ,
10158 .Va spamc-command , spamc-arguments , spamc-user ,
10159 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
10162 .Va spamfilter-rate-scanscore .
10170 In general it is a good idea to turn on
10176 twice) if something doesn't work well.
10177 Very often a diagnostic message can be produced that leads to the
10178 problems' solution.
10180 .\" .Ss "\*(UA shortly hangs on startup" {{{
10181 .Ss "\*(UA shortly hangs on startup"
10183 This can have two reasons, one is the necessity to wait for a file lock
10184 and can't be helped, the other being that \*(UA calls the function
10186 in order to query the nodename of the box (sometimes the real one is
10187 needed instead of the one represented by the internal variable
10189 You may have varying success by ensuring that the real hostname and
10193 or, more generally, that the name service is properly setup \(en
10196 return what you'd expect?
10197 Does this local hostname has a domain suffix?
10198 RFC 6762 standardized the link-local top-level domain
10202 .\" .Ss "I can't login to Google mail aka GMail" {{{
10203 .Ss "I can't login to Google mail aka GMail"
10205 Since 2014 some free service providers classify programs as
10207 unless they use a special authentification method (OAuth 2.0) which
10208 wasn't standardized for non-HTTP protocol authentication token query
10209 until August 2015 (RFC 7628).
10212 Different to Kerberos / GSSAPI, which is developed since the mid of the
10213 1980s, where a user can easily create a local authentication ticket for
10214 her- and himself with the locally installed
10216 program, that protocol has no such local part but instead requires
10217 a world-wide-web query to create or fetch a token; since there is no
10218 local cache this query has to be performed whenever \*(UA is invoked
10219 from the command line (in interactive sessions situation may differ).
10222 \*(UA doesn't support OAuth.
10223 Because of this it is necessary to declare \*(UA a
10224 .Dq less secure app
10225 (on the providers account web page) in order to read and send mail.
10226 However, it also seems possible to take the following steps instead:
10231 give the provider the number of a mobile phone,
10234 .Dq 2-Step Verification ,
10236 create an application specific password (16 characters), and
10238 use that special password instead of your real Google account password in
10239 \*(UA (for more on that see the section
10240 .Sx "On URL syntax and credential lookup" ) .
10244 .\" .Ss "Not \(dqdefunctional\(dq, but the editor key won't work" {{{
10245 .Ss "Not \(dqdefunctional\(dq, but the editor key won't work"
10247 It can happen that the terminal library (see
10248 .Sx "On terminal control and line editor",
10251 reports different codes than the terminal really sends, in which case
10252 \*(UA will tell that a key binding is functional, but won't be able to
10253 recognize it because the received data doesn't match anything expected.
10254 The verbose listing of
10256 ings will show the byte sequences that are expected.
10259 To overcome the situation, use, e.g., the program
10261 in conjunction with the
10263 flag if available, to see the byte sequences which are actually produced
10264 by keypresses, and use the variable
10266 to make \*(UA aware of them.
10267 E.g., the terminal this is typed on produces some false sequences, here
10268 an example showing the shifted home key:
10270 .Bd -literal -offset indent
10273 # 1B 5B=[ 31=1 3B=; 32=2 48=H
10278 ? \*(uA -v -Stermcap='kHOM=\eE[H'
10287 .\" .Sh "SEE ALSO" {{{
10297 .Xr spamassassin 1 ,
10306 .Xr mailwrapper 8 ,
10311 .\" .Sh HISTORY {{{
10314 M. Douglas McIlroy writes in his article
10315 .Dq A Research UNIX Reader: Annotated Excerpts \
10316 from the Programmer's Manual, 1971-1986
10319 command already appeared in First Edition
10323 .Bd -ragged -offset indent
10324 Electronic mail was there from the start.
10325 Never satisfied with its exact behavior, everybody touched it at one
10326 time or another: to assure the safety of simultaneous access, to improve
10327 privacy, to survive crashes, to exploit uucp, to screen out foreign
10328 freeloaders, or whatever.
10329 Not until v7 did the interface change (Thompson).
10330 Later, as mail became global in its reach, Dave Presotto took charge and
10331 brought order to communications with a grab-bag of external networks
10337 Mail was written in 1978 by Kurt Shoens and developed as part of the
10340 distribution until 1995.
10341 Mail has then seen further development in open source
10343 variants, noticeably by Christos Zoulas in
10345 Basing upon this Nail, later Heirloom Mailx, was developed by Gunnar
10346 Ritter in the years 2000 until 2008.
10347 Since 2012 S-nail is maintained by Steffen (Daode) Nurpmeso.
10348 This man page is derived from
10349 .Dq The Mail Reference Manual
10350 that was originally written by Kurt Shoens.
10356 .An "Kurt Shoens" ,
10357 .An "Edward Wang" ,
10358 .An "Keith Bostic" ,
10359 .An "Christos Zoulas" ,
10360 .An "Gunnar Ritter" ,
10361 .An "Steffen Nurpmeso" Aq Mt s-nail-users@lists.sourceforge.net
10363 .Mt s-mailx@sdaoden.eu ) .
10366 .\" .Sh CAVEATS {{{
10369 \*(ID Interrupting an operation via
10373 is often problematic: many library functions cannot deal with the
10375 that this software (still) performs.
10378 The SMTP and POP3 protocol support of \*(UA is very basic.
10379 Also, if it fails to contact its upstream SMTP server, it will not make
10380 further attempts to transfer the message at a later time (setting
10385 If this is a concern, it might be better to set up a local SMTP server
10386 that is capable of message queuing.
10392 After deleting some message of a POP3 mailbox the header summary falsely
10393 claims that there are no messages to display, you need to perform
10394 a scroll or dot movement to restore proper state.
10396 In threaded display a power user may encounter crashes very
10397 occasionally (this is may and very).
10401 in the source repository lists future directions.