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.
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34 .\" S-nail(1): v14.9.0-pre1 / 2016-09-15
36 .ds VV \\%v14.9.0-pre1
46 .\" If not ~/.mailrc, it breaks POSIX compatibility. And adjust main.c.
51 .ds OU [no v15-compat]
52 .ds ID [v15 behaviour may differ]
53 .ds NQ [Only new quoting rules]
64 .Nd send and receive Internet mail
70 .\" Keep in SYNC: ./nail.1:"SYNOPSIS, main()
78 .Op Fl a Ar attachment
81 .Op Fl M Ar type | Fl m Ar file | Fl q Ar file | Fl t
83 .Op Fl S Ar var Ns Op Ns = Ns Ar value
88 .Op Fl Fl \~ Ns Ar mta-option ...
97 .Op Fl S Ar var Ns Op Ns = Ns Ar value
100 .Op Fl Fl \~ Ns Ar mta-option ...
108 .Op Fl L Ar spec-list
109 .Op Fl r Ar from-addr
110 .Op Fl S Ar var Ns Op Ns = Ns Ar value
113 .Op Fl Fl \~ Ns Ar mta-option ...
118 .Mx -toc -tree html pdf ps xhtml
121 .\" .Sh DESCRIPTION {{{
124 .Bd -filled -compact -offset indent
125 .Sy Compatibility note:
126 S-nail (\*(UA) will wrap up into \%S-mailx in v15.0 (circa 2018).
127 Backward incompatibility has to be expected \(en
131 -style argument quoting rules, for example.
132 New and old behaviour is flagged \*(IN and \*(OU, and setting
135 .Sx "INTERNAL VARIABLES" ,
136 will choose new behaviour when applicable.
137 \*(OB flags what will vanish, and enabling
141 enables obsoletion warnings.
145 \*(UA is a mail processing system with a command syntax reminiscent of
147 with lines replaced by messages.
148 It is intended to provide the functionality of the POSIX
150 command, but is MIME capable and optionally offers extensions for
151 line editing, S/MIME, SMTP and POP3 among others.
153 .\" .Ss "Options" {{{
156 .Bl -tag -width ".Fl _ Ar _ddr"
159 Explicitly control which of the
161 shall be loaded: if the letter
163 is (case-insensitively) part of the
167 is loaded, likewise the letter
169 controls loading of the user's personal
171 file, whereas the letters
175 explicitly forbid loading of any resource files.
176 This option should be used by scripts: to avoid environmental noise they
179 from any configuration files and create a script-local environment,
180 explicitly setting any of the desired
181 .Sx "INTERNAL VARIABLES"
184 This option overrides
191 command for the given user email
193 after program startup is complete.
194 Being a special incarnation of
196 macros for the purpose of bundling longer-lived settings, activating
197 such an email account also switches to the accounts system
203 Attach the given file to the message.
204 The same filename conventions as described in the section
206 apply: shell word expansion is restricted to the tilde
210 not be accessible but contain a
212 character, then anything after the
214 is assumed to specify the input character set and anything before
216 the filename: this is the only option to specify the input character set
217 (and don't perform any character set conversion) for text attachments
218 from the command line, not using the
220 tilde escape command.
224 Make standard input and standard output line-buffered.
228 Send a blind carbon copy to
231 May be used multiple times.
233 .Sx "On sending mail, and non-interactive mode" .
237 Send carbon copies to the given receiver.
238 May be used multiple times.
243 the internal variable
245 which enables debug messages and disables message delivery,
246 among others; effectively turns almost any operation into a dry-run.
252 and thus discard messages with an empty message part body.
253 This is useful for sending messages from scripts.
257 Just check if mail is present (in the specified or system
259 if yes, return an exit status of zero, a non-zero value otherwise.
260 To restrict the set of mails to consider in this evaluation a message
261 specification can be added with the option
266 Save the message to send in a file named after the local part of the
267 first recipient's address (instead of in
272 Read in the contents of the user's
274 (or the specified file) for processing;
275 when \*(UA is quit, it writes undeleted messages back to this file
279 Some special conventions are recognized for the optional
281 argument which are documented for the
286 is not a argument to the flag
288 but is instead taken from the command line after option processing has
292 that starts with a hyphen, prefix it with a (relative) path, as in
293 .Ql ./-hyphenbox.mbox .
297 Display a summary of the
299 of all messages in the specified mailbox or system
302 A configurable summary view is available via the
308 Show a short usage summary.
309 Because of widespread use a
311 argument will have the same effect.
317 to ignore tty interrupt signals.
320 .It Fl L Ar spec-list
321 Display a summary of all
323 of only those messages in the specified mailbox or the system
329 .Sx "Specifying messages"
336 option has been given in addition no header summary is produced,
337 but \*(UA will instead indicate via its exit status whether
343 note that any verbose output is suppressed in this mode and must instead
344 be enabled explicitly (e.g., by using the option
349 Special send mode that will flag standard input with the MIME
353 and use it as the main message body.
354 \*(ID Using this option will bypass processing of
355 .Va message-inject-head ,
358 .Va message-inject-tail .
364 Special send mode that will MIME classify the specified
366 and use it as the main message body.
367 \*(ID Using this option will bypass processing of
368 .Va message-inject-head ,
371 .Va message-inject-tail .
379 and thus inhibit initial display of message headers when reading mail or
380 editing a mail folder.
384 Standard flag that inhibits reading the system wide
389 allows more control over the startup sequence; also see
390 .Sx "Resource files" .
394 Special send mode that will initialize the message body with the
395 contents of the specified
397 which may be standard input
399 only in non-interactive context.
405 Any folder opened will be in read-only mode.
408 .It Fl r Ar from-addr
411 is a valid address then it specifies the envelope sender address to be
412 passed to a file-based
414 (Mail-Transfer-Agent) as
416 when a message is send.
419 include a user name, then the address components will be separated and
420 the name part will be passed to file-based
426 will also be assigned to the
429 .Ql -Sfrom=from-addr ) ,
430 therefore affecting possible SMTP
432 data transfer; note this assignment does not cause value fixation.
434 If instead an empty string is passed as
436 then the content of the variable
438 will be evaluated and used for this purpose whenever the
441 Note that \*(UA by default, without
443 that is, neither passes
447 flags to a file-based MTA by itself.
450 .It Fl S Ar var Ns Op = Ns value
454 iable and, in case of a non-boolean variable which has a value, assign
458 .Sx "INTERNAL VARIABLES"
462 may be overwritten from within resource files,
463 the command line setting will be reestablished after all resource files
468 Specify the subject of the to-be-sent message.
472 The message given (on standard input) is expected to contain, separated
473 from the message body by an empty line, a message header with
478 fields giving its recipients, which will be added to any recipients
479 specified on the command line.
480 If a message subject is specified via
482 then it'll be used in favour of one given on the command line.
498 .Ql Mail-Followup-To: ,
499 by default created automatically dependent on message context, will
500 be used if specified (a special address massage will however still occur
502 Any other (even custom) header field is passed through entirely
503 unchanged, and in conjunction with the option
505 it is even possible to embed
512 Initially read the primary system mailbox of
514 appropriate privileges presumed; effectively identical to
524 will also show the list of
526 .Ql $ \*(uA -Xversion -Xx .
531 ting the internal variable
533 enables display of some informational context messages.
534 Using it twice increases the level of verbosity.
538 Add the given (or multiple for a multiline argument)
540 to the list of commands to be executed (as a unit, just as via
542 before normal operation starts.
546 .Va batch-exit-on-error ;
547 the only possibility to execute commands in non-interactive mode when
548 reading startup files is actively prohibited.
554 even if not in interactive mode.
555 This can be used to, e.g., automatically format the composed message
556 text before sending the message:
557 .Bd -literal -offset indent
558 $ ( echo 'line one. Word. Word2.'; \e
559 echo '~| /usr/bin/fmt -tuw66' ) |\e
560 LC_ALL=C \*(uA -:/ -Sttycharset=UTF-8 -d~ bob@exam.ple
566 In batch mode the full set of commands is available, just like in
567 interactive mode, and diverse variable settings and internal states are
568 adjusted for batch necessities, e.g., it
585 is enabled in compose mode.
586 The following prepares an email message in a batched dry run:
587 .Bd -literal -offset indent
588 $ LC_ALL=C printf 'm bob\en~s ubject\enText\en~.\enx\en' | \e
589 LC_ALL=C \*(uA -:/ -d# -X'alias bob bob@exam.ple'
594 This flag forces termination of option processing in order to prevent
597 It also forcefully puts \*(UA into send mode, see
598 .Sx "On sending mail, and non-interactive mode" .
602 In the above list of supported command line options,
606 are implemented by means of
608 ting the respective option, as via
611 .Op Ar mta-option ...
613 arguments that are given at the end of the command line after a
615 separator will be passed through to a file-based
617 (Mail-Transfer-Agent) and persist for an entire (interactive) session
618 \(en if the setting of
620 allows their recognition; no such constraints apply to the variable
624 .\" .Ss "A starter" {{{
627 \*(UA is a direct descendant of
629 Mail, a successor of the Research
632 .Dq was there from the start
637 Mail reference manual begins with the following words:
639 .Bd -ragged -offset indent
640 Mail provides a simple and friendly environment for sending and
642 It divides incoming mail into its constituent messages and allows the
643 user to deal with them in any order.
644 In addition, it provides a set of
646 -like commands for manipulating messages and sending mail.
647 Mail offers the user simple editing capabilities to ease the composition
648 of outgoing messages, as well as providing the ability to define and
649 send to names which address groups of users.
653 \*(UA is thus the user side of the
655 mail system, whereas the system side (Mail-Transfer-Agent, MTA) was
656 traditionally taken by
658 and most MTAs provide a binary of this name for compatibility purposes.
663 of \*(UA then the system side is not a mandatory precondition for mail
667 Because \*(UA strives for compliance with POSIX
669 it is likely that some configuration settings have to be adjusted before
670 using it is a smooth experience.
673 resource file bends those standard imposed settings of the
674 .Sx "INTERNAL VARIABLES"
675 a bit towards more user friendliness and safety, however, e.g., it
680 in order to suppress the automatic moving of messages to
682 that would otherwise occur (see
683 .Sx "Message states" )
686 to not remove empty files in order not to mangle file permissions when
687 files eventually get recreated (\*(UA actively manages the file mode
690 upon program startup).
693 in order to synchronize \*(UA with the exit status report of the used
698 contains some more complete configuration examples.
701 .\" .Ss "On sending mail, and non-interactive mode" {{{
702 .Ss "On sending mail, and non-interactive mode"
704 To send a message to one or more people, using a local or a builtin
706 (Mail-Transfer-Agent) transport to actually deliver the generated mail
707 message, \*(UA can be invoked with arguments which are the names of
708 people to whom the mail will be sent, and the command line options
712 can be used to add (blind) carbon copy receivers:
714 .Bd -literal -offset indent
715 $ \*(uA -s ubject -a ttach.txt bill@exam.ple
716 # But... try it in an isolated dry-run mode first
717 $ LC_ALL=C \*(uA -:/ -d -vv -Ssendwait \e
718 -b bcc@exam.ple -c cc@exam.ple -. \e
719 '(Lovely) Bob <bob@exam.ple>' eric@exam.ple
721 $ LC_ALL=C \*(uA -:/ -d -vv -Sv15-compat -Ssendwait \e
722 -S 'mta=smtps://mylogin@exam.ple:465' -Ssmtp-auth=login \e
723 -S 'from=scriptreply@exam.ple' \e
729 If standard input is a terminal rather than the message to be sent,
730 the user is expected to type in the message contents.
731 In this compose mode \*(UA treats lines beginning with the character
733 special \(en these are so-called
735 which can be used to read in files, process shell commands, add and edit
736 attachments and more; e.g., the tilde escape
738 will start the text editor to revise the message in it's current state,
740 allows editing of the most important message headers and
742 gives an overview of available tilde escapes.
746 at the beginning of an empty line leaves compose mode and causes the
747 message to be sent, whereas typing
750 twice will abort the current letter (saving its contents in the file
756 Messages are sent asynchronously, without supervision, unless the variable
758 is set, therefore send errors are not recognizable until then.
764 .Sx "INTERNAL VARIABLES"
765 can be used to alter default behavior; e.g.,
770 will automatically startup a text editor when compose mode is entered,
772 will cause the user to be prompted actively for carbon-copy recipients
775 option will allow leaving compose mode by writing a line consisting
781 hook macros may be set to automatically adjust some settings dependent
782 on receiver, sender or subject contexts.
785 Especially for using public mail provider accounts with the SMTP
787 it is often necessary to set
789 and saving a copy of sent messages in a
791 may be desirable \(en as for most mailbox file targets some special
792 syntax conventions are recognized (see the
794 command for more on that).
797 for the purpose of arranging a complete environment of settings that can
798 be switched to with a single command or command line option may be
801 contains example configurations for sending messages via some of the
802 well-known public mail providers and also gives a compact overview on
803 how to setup a secure SSL/TLS environment).
808 sandbox dry-run tests first will prove correctness.
812 .Sx "On URL syntax and credential lookup"
813 will spread light on the different ways of how to specify user email
814 account credentials, the
816 variable chains, and accessing protocol-specific resources,
819 goes into the details of character encoding and how to use them for
820 representing messages and MIME part contents by specifying them in
822 and reading the section
823 .Sx "The mime.types files"
824 should help to understand how the MIME-type of outgoing attachments are
825 classified, and what can be done for fine-tuning.
828 Message recipients (as specified on the command line or defined in
833 may not only be email addressees but can also be names of mailboxes and
834 even complete shell command pipe specifications.
837 is not set then only network addresses (see
839 for a description of mail addresses) and plain user names (including MTA
840 aliases) may be used, other types will be filtered out, giving a warning
843 .\" When changing any of the following adjust any RECIPIENTADDRSPEC;
844 .\" grep the latter for the complete picture
848 is set then extended recipient addresses will optionally be accepted:
849 Any name which starts with a vertical bar
851 character specifies a command pipe \(en the command string following the
853 is executed and the message is sent to its standard input;
854 Likewise, any name that starts with the character solidus
856 or the character sequence dot solidus
858 is treated as a file, regardless of the remaining content.
859 Any other name which contains an at sign
861 character is treated as a network address;
862 Any other name which starts with a plus sign
864 character specifies a mailbox name;
865 Any other name which contains a solidus
867 character but no exclamation mark
871 character before also specifies a mailbox name;
872 What remains is treated as a network address.
874 .Bd -literal -offset indent
875 $ echo bla | \*(uA -Sexpandaddr -s test ./mbox.mbox
876 $ echo bla | \*(uA -Sexpandaddr -s test '|cat >> ./mbox.mbox'
877 $ echo safe | LC_ALL=C \e
878 \*(uA -:/ -Sv15-compat -Ssendwait -Snosave \e
879 -Sexpandaddr=fail,-all,+addr -s test \e
884 It is possible to create personal distribution lists via the
886 command, so that, for instance, the user can send mail to
888 and have it go to a group of people.
889 These aliases have nothing in common with the system wide aliases that
890 may be used by the MTA, which are subject to the
894 and are often tracked in a file
900 Personal aliases will be expanded by \*(UA before the message is sent,
901 and are thus a convenient alternative to specifying each addressee by
905 .Dl alias cohorts bill jkf mark kridle@ucbcory ~/mail/cohorts.mbox
908 To avoid environmental noise scripts should
910 \*(UA from any configuration files and create a script-local
911 environment, ideally with the command line options
913 to disable any configuration file in conjunction with repetitions of
915 to specify variables:
917 .Bd -literal -offset indent
918 $ env LC_ALL=C \*(uA -:/ \e
919 -Sv15-compat -Ssendwait -Snosave -Sttycharset=utf-8 \e
920 -Sexpandaddr=fail,-all,+addr \e
921 -S 'mta=smtps://mylogin@exam.ple:465' -Ssmtp-auth=login \e
922 -S 'from=scriptreply@exam.ple' \e
923 -s 'subject' -a attachment_file \e
924 -. "Recipient 1 <rec1@exam.ple>" rec2@exam.ple \e
929 As shown, scripts can
931 a locale environment, the above specifies the all-compatible 7-bit clean
934 but will nonetheless take and send UTF-8 in the message text by using
936 In interactive mode, which is introduced in the next section, messages
937 can be sent by calling the
939 command with a list of recipient addresses \(em the semantics are
940 completely identical to non-interactive message sending:
942 .Bd -literal -offset indent
943 $ \*(uA -d -Squiet -Semptystart
944 "/var/spool/mail/user": 0 messages
945 ? mail "Recipient 1 <rec1@exam.ple>", rec2@exam.ple
946 ? # Will do the right thing (tm)
947 ? m rec1@exam.ple rec2@exam.ple
951 .\" .Ss "On reading mail, and interactive mode" {{{
952 .Ss "On reading mail, and interactive mode"
954 When invoked without addressees \*(UA enters interactive mode in which
956 When used like that the user's system
960 for an in-depth description of the different mailbox types that exist)
961 is read in and a one line header of each message therein is displayed.
962 The visual style of this summary of
964 can be adjusted through the variable
966 and the possible sorting criterion via
972 can be performed with the command
974 If the initially opened mailbox is empty \*(UA will instead exit
975 immediately (after displaying a message) unless the variable
984 will give a listing of all available commands and
986 will give a summary of some common ones.
987 If the \*(OPal documentation strings are available one can type
990 and see the actual expansion of
992 and what it's purpose is, i.e., commands can be abbreviated
993 (note that POSIX defines some abbreviations, so that the alphabetical
994 order of commands doesn't necessarily relate to the abbreviations; it is
995 possible to define overwrites with the
998 These commands can also produce a more
1003 Messages are given numbers (starting at 1) which uniquely identify
1004 messages; the current message \(en the
1006 \(en will either be the first new message, or the first unread message,
1007 or the first message of the mailbox; the option
1009 will instead cause usage of the last message for this purpose.
1014 ful of header summaries containing the
1018 will display only the summaries of the given messages, defaulting to the
1022 Message content can be displayed on the users' terminal with the
1026 If instead the command
1028 is used, only the first
1030 of a message will be shown.
1031 By default the current message
1033 is displayed, but like with many other commands it is possible to give
1034 a fancy message specification (see
1035 .Sx "Specifying messages" ) ,
1038 will display all unread messages,
1043 will type the messages 1 and 5,
1045 will type the messages 1 through 5, and
1049 will display the last and the next message, respectively.
1052 (a more substantial alias of the standard command
1054 will display a header summary of the given message specification list
1055 instead of their content, e.g., the following will search for subjects:
1058 .Dl from "'@Some subject to search for'"
1061 In the default setup all header fields of a message will be
1063 d, but this can be changed: either by blacklisting a list of fields via
1065 or by whitelisting only a given list with the
1068 .Ql Ic \:retain Ns \0from_ date from to cc subject .
1069 In order to display all header fields of a message regardless of
1070 currently active ignore or retain lists, use the commands
1076 controls whether and when \*(UA will use the configured
1078 for display instead of directly writing to the user terminal
1080 (generally speaking).
1081 Note that historically the global
1083 not only adjusts the list of displayed headers, but also sets
1087 Dependent upon the configuration a line editor (see the section
1088 .Sx "On terminal control and line editor" )
1089 aims at making user experience with the many
1092 When reading the system
1098 specified a mailbox explicitly prefixed with the special
1100 modifier (propagating the mailbox to a primary one) then messages which
1101 have been read will be moved to a secondary mailbox, the user's
1103 file, automatically when the mailbox is left, either by changing the
1104 active mailbox or by quitting \*(UA (also see
1105 .Sx "Message states" )
1106 \(en this automatic moving from a system or primary to the secondary
1107 mailbox is not performed when the variable
1112 After examining a message the user can also
1116 to the sender and all recipients or
1118 exclusively to the sender(s).
1119 Messages can also be
1121 ed (shorter alias is
1123 Note that when replying to or forwarding a message recipient addresses
1124 will be stripped from comments and names unless the option
1127 Deletion causes \*(UA to forget about the message;
1128 This is not irreversible, though, one can
1130 the message by giving its number,
1131 or the \*(UA session can be ended by giving the
1136 To end a mail processing session one may either issue
1138 to cause a full program exit, which possibly includes
1139 automatic moving of read messages to
1141 as well as updating the \*(OPal line editor
1145 instead in order to prevent any of these actions.
1148 .\" .Ss "HTML mail and MIME attachments" {{{
1149 .Ss "HTML mail and MIME attachments"
1151 Messages which are HTML-only get more and more common and of course many
1152 messages come bundled with a bouquet of MIME attachments.
1153 Whereas \*(UA \*(OPally supports a simple HTML-to-text converter to deal
1154 with HTML messages (see
1155 .Sx "The mime.types files" ) ,
1156 it normally can't deal with any of these itself, but instead programs
1157 need to become registered to deal with specific MIME types or file
1159 These programs may either prepare plain text versions of their input
1160 in order to enable \*(UA to display the content on the terminal,
1161 or display the content themselves, for example in a graphical window.
1164 To install an external handler program for a specific MIME type set an
1166 .Va pipe-TYPE/SUBTYPE
1167 variable; to instead define a handler for a specific file extension set
1170 variable \(en these handlers take precedence.
1171 \*(OPally \*(UA supports mail user agent configuration as defined in
1172 RFC 1524; this mechanism, documented in the section
1173 .Sx "The Mailcap files" ,
1174 will be queried for display or quote handlers if none of the former two
1175 .\" TODO v15-compat "will be" -> "is"
1176 did; it will be the sole source for handlers of other purpose.
1177 A last source for handlers may be the MIME type definition itself, if
1178 the \*(UA specific type-marker extension was used when defining the type
1181 (Many of the builtin MIME types do so by default.)
1185 .Va mime-counter-evidence
1186 can be set to improve dealing with faulty MIME part declarations as are
1187 often seen in real-life messages.
1188 E.g., to display a HTML message inline (that is, converted to a more
1189 fancy plain text representation than the builtin converter is capable to
1190 produce) with either of the text-mode browsers
1194 teach \*(UA about MathML documents and make it display them as plain
1195 text, and to open PDF attachments in an external PDF viewer,
1196 asynchronously and with some other magic attached:
1198 .Bd -literal -offset indent
1199 if $features !@ +filter-html-tagsoup
1200 #set pipe-text/html='elinks -force-html -dump 1'
1201 set pipe-text/html='lynx -stdin -dump -force_html'
1202 # Display HTML as plain text instead
1203 #set pipe-text/html=@
1205 mimetype '@ application/mathml+xml mathml'
1206 wysh set pipe-application/pdf='@&=@ \e
1207 trap "rm -f \e"${NAIL_FILENAME_TEMPORARY}\e"" EXIT;\e
1208 trap "trap \e"\e" INT QUIT TERM; exit 1" INT QUIT TERM;\e
1209 mupdf "${NAIL_FILENAME_TEMPORARY}"'
1213 Note: special care must be taken when using such commands as mail
1214 viruses may be distributed by this method: if messages of type
1215 .Ql application/x-sh
1216 or files with the extension
1218 were blindly filtered through the shell, for example, a message sender
1219 could easily execute arbitrary code on the system \*(UA is running on.
1220 For more on MIME, also in respect to sending of messages, see the
1222 .Sx "The mime.types files" ,
1223 .Sx "The Mailcap files"
1228 .\" .Ss "Mailing lists" {{{
1231 \*(UA offers some support to ease handling of mailing lists.
1234 promotes all given arguments to known mailing lists, and
1236 sets their subscription attribute, creating them first as necessary.
1241 automatically, but only resets the subscription attribute.)
1242 Using the commands without arguments will show (a subset of) all
1243 currently defined mailing lists.
1248 can be used to mark out messages with configured list addresses
1249 in the header display.
1252 \*(OPally mailing lists may also be specified as (extended) regular
1253 expressions, which allows matching of many addresses with a single
1255 However, all fully qualified list addresses are matched via a fast
1256 dictionary, whereas expressions are placed in (a) list(s) which is
1257 (are) matched sequentially.
1259 .Bd -literal -offset indent
1260 set followup-to followup-to-honour=ask-yes reply-to-honour=ask-yes
1261 wysh mlist a1@b1.c1 a2@b2.c2 '.*@lists\e.c3$'
1262 mlsubscribe a4@b4.c4 exact@lists.c3
1267 .Va followup-to-honour
1269 .Ql Mail-\:Followup-\:To:
1270 header is honoured when the message is being replied to (via
1276 controls whether this header is created when sending mails; it will be
1277 created automatically for a couple of reasons, too, like when the
1279 .Dq mailing list specific
1284 is used to respond to a message with its
1285 .Ql Mail-Followup-To:
1289 A difference in between the handling of known and subscribed lists is
1290 that the address of the sender is usually not part of a generated
1291 .Ql Mail-Followup-To:
1292 when addressing the latter, whereas it is for the former kind of lists.
1293 Usually because there are exceptions: say, if multiple lists are
1294 addressed and not all of them are subscribed lists.
1296 For convenience \*(UA will, temporarily, automatically add a list
1297 address that is presented in the
1299 header of a message that is being responded to to the list of known
1301 Shall that header have existed \*(UA will instead, dependent on the
1303 .Va reply-to-honour ,
1306 for this purpose in order to accept a list administrators' wish that
1307 is supposed to have been manifested like that (but only if it provides
1308 a single address which resides on the same domain as what is stated in
1312 .\" .Ss "Resource files" {{{
1313 .Ss "Resource files"
1315 Upon startup \*(UA reads in several resource files:
1317 .Bl -tag -width ".It Pa _AIL_EXTRA_R_"
1320 System wide initialization file.
1321 Reading of this file can be suppressed, either by using the
1325 command line options, or by setting the
1328 .Ev NAIL_NO_SYSTEM_RC .
1332 File giving initial commands.
1333 A different file can be chosen by setting the
1337 Reading of this file can be suppressed with the
1339 command line option.
1341 .It Va NAIL_EXTRA_RC
1342 Can be used to define an optional startup file to be read after all
1343 other resource files.
1344 It can be used to specify settings that are not understood by other
1346 implementations, for example.
1347 This variable is only honoured when defined in a resource file, e.g.,
1349 .Sx "INTERNAL VARIABLES" .
1353 The content of these files is interpreted as follows:
1356 .Bl -bullet -compact
1358 A lines' leading whitespace is removed.
1360 Empty lines are ignored.
1362 Any other line is interpreted as a command.
1363 It may be spread over multiple input lines if the newline character is
1365 by placing a reverse solidus character
1367 as the last character of the line; whereas any leading whitespace of
1368 follow lines is ignored, trailing whitespace before a escaped newline
1369 remains in the input.
1371 If the line (content) starts with the number sign
1373 then it is a comment-command \(en a real command! \(en and also ignored.
1374 This command is the only form of comment that is understood.
1378 Unless \*(UA is about to enter interactive mode syntax errors that occur
1379 while loading these files are treated as errors and cause program exit.
1380 More files with syntactically equal content can be
1382 The following, saved in a file, would be an examplary content:
1384 .Bd -literal -offset indent
1385 # This line is a comment command. And y\e
1386 es, it is really continued here.
1393 .\" .Ss "Character sets" {{{
1394 .Ss "Character sets"
1396 \*(OP \*(UA detects the character set of the terminal by using
1397 mechanisms that are controlled by the
1402 should give an overview); the \*(UA internal variable
1404 will be set to the detected terminal character set accordingly
1405 and will thus show up in the output of the commands
1411 However, a user supplied
1413 value is not overwritten by this detection mechanism: this
1415 must be used if the detection doesn't work properly,
1416 and it may be used to adjust the name of the locale character set.
1417 E.g., on BSD systems one may use a locale with the character set
1418 ISO8859-1, which is not a valid name for this character set; to be on
1419 the safe side, one may set
1421 to the correct name, which is ISO-8859-1.
1424 Note that changing the value doesn't mean much beside that,
1425 since several aspects of the real character set are implied by the
1426 locale environment of the system,
1427 and that stays unaffected by the content of an overwritten
1430 (This is mostly an issue when interactively using \*(UA, though.
1431 It is actually possible to send mail in a completely
1433 locale environment, an option that \*(UA's test-suite uses excessively.)
1436 If no character set conversion capabilities have been compiled into
1439 doesn't include the term
1443 will be the only supported character set,
1444 it is simply assumed that it can be used to exchange 8-bit messages,
1445 and the rest of this section does not apply;
1446 it may however still be necessary to explicitly set it if automatic
1447 detection fails, since in that case it defaults to the mentioned
1448 .\" (Keep in SYNC: ./nail.1:"Character sets", ./nail.h:CHARSET_*!)
1452 When reading messages, their text is converted into
1454 as necessary in order to display them on the users terminal.
1455 Unprintable characters and invalid byte sequences are detected
1456 and replaced by proper substitution characters (unless the variable
1458 was set once \*(UA was started).
1460 .Va charset-unknown-8bit
1461 to deal with another hairy aspect of message interpretation.
1464 When sending messages all their parts and attachments are classified.
1465 Whereas no character set conversion is performed on those parts which
1466 appear to be binary data,
1467 the character set being used must be declared within the MIME header of
1468 an outgoing text part if it contains characters that do not conform to
1469 the set of characters that are allowed by the email standards.
1470 Permissible values for character sets can be declared using the
1474 which defines a catch-all last-resort fallback character set that is
1475 implicitly appended to the list of character-sets in
1479 When replying to a message and the variable
1480 .Va reply-in-same-charset
1481 is set then the character set of the message being replied to is tried
1483 And it is also possible to make \*(UA work even more closely related to
1484 the current locale setting automatically by using the variable
1485 .Va sendcharsets-else-ttycharset ,
1486 please see there for more information.
1489 All the specified character sets are tried in order unless the
1490 conversion of the part or attachment succeeds.
1491 If none of the tried (8-bit) character sets is capable to represent the
1492 content of the part or attachment,
1493 then the message will not be sent and its text will optionally be
1497 In general, if the message
1498 .Dq Cannot convert from a to b
1499 appears, either some characters are not appropriate for the currently
1500 selected (terminal) character set,
1501 or the needed conversion is not supported by the system.
1502 In the first case, it is necessary to set an appropriate
1504 locale and/or the variable
1508 The best results are usually achieved when \*(UA is run in a UTF-8
1509 locale on a UTF-8 capable terminal, in which case the full Unicode
1510 spectrum of characters is available.
1511 In this setup characters from various countries can be displayed,
1512 while it is still possible to use more simple character sets for sending
1513 to retain maximum compatibility with older mail clients.
1516 On the other hand the POSIX standard defines a locale-independent 7-bit
1517 .Dq portable character set
1518 that should be used when overall portability is an issue, the even more
1519 restricted subset named
1520 .Dq portable filename character set
1521 consisting of A-Z, a-z, 0-9, period
1530 .\" .Ss "Message states" {{{
1531 .Ss "Message states"
1533 \*(UA differentiates in between several different message states;
1534 the current state will be reflected in header summary displays if
1536 is configured to do so (via the internal variable
1538 and messages can also be selected and be acted upon depending on their
1540 .Sx "Specifying messages" ) .
1541 When operating on the system
1543 or in primary mailboxes opened with the special prefix
1547 special actions, like the automatic moving of messages to the secondary
1549 mailbox may be applied when the mailbox is left (also implicitly via
1550 a successful exit of \*(UA, but not if the special command
1552 is used) \(en however, because this may be irritating to users which
1555 mail-user-agents, the default global
1561 variables in order to suppress this behaviour.
1563 .Bl -tag -width ".It Ql _reserved"
1565 Message has neither been viewed nor moved to any other state.
1566 Such messages are retained even in the primary system mailbox.
1569 Message has neither been viewed nor moved to any other state, but the
1570 message was present already when the mailbox has been opened last:
1571 Such messages are retained even in the primary system mailbox.
1574 The message has been processed by one of the following commands:
1594 commands may also cause the next message to be marked as read, depending
1600 command is used, messages that are in the primary system mailbox or in
1601 mailboxes which were opened with the special
1605 state when the mailbox is left will be saved in
1612 The message has been processed by one of the following commands:
1618 can be used to access such messages.
1621 The message has been processed by a
1623 command and it will be retained in its current location.
1626 The message has been processed by one of the following commands:
1632 command is used, messages that are in the primary system mailbox or in
1633 mailboxes which were opened with the special
1637 state when the mailbox is left will be deleted; they will be saved in
1645 .\" .Ss "Specifying messages" {{{
1646 .Ss "Specifying messages"
1653 can be given a list of message numbers as arguments to apply to a number
1654 of messages at once.
1657 deletes messages 1 and 2,
1660 will delete the messages 1 through 5.
1661 In sorted or threaded mode (see the
1665 will delete the messages that are located between (and including)
1666 messages 1 through 5 in the sorted/threaded order, as shown in the
1669 The following special message names exist:
1672 .Bl -tag -width ".It Ar _n_u"
1674 The current message, the so-called
1678 The message that was previously the current message.
1681 The parent message of the current message,
1682 that is the message with the Message-ID given in the
1684 field or the last entry of the
1686 field of the current message.
1689 The next previous undeleted message,
1690 or the next previous deleted message for the
1693 In sorted/threaded mode,
1694 the next previous such message in the sorted/threaded order.
1697 The next undeleted message,
1698 or the next deleted message for the
1701 In sorted/threaded mode,
1702 the next such message in the sorted/threaded order.
1705 The first undeleted message,
1706 or the first deleted message for the
1709 In sorted/threaded mode,
1710 the first such message in the sorted/threaded order.
1714 In sorted/threaded mode,
1715 the last message in the sorted/threaded order.
1719 selects the message addressed with
1723 is any other message specification,
1724 and all messages from the thread that begins at it.
1725 Otherwise it is identical to
1730 the thread beginning with the current message is selected.
1735 All messages that were included in the message list for the previous
1739 An inclusive range of message numbers.
1740 Selectors that may also be used as endpoints include any of
1745 .Dq any substring matches
1748 header, which will match addresses (too) even if
1750 is set (and POSIX says
1751 .Dq any address as shown in a header summary shall be matchable in this form ) ;
1754 variable is set, only the local part of the address is evaluated
1755 for the comparison, not ignoring case, and the setting of
1757 is completely ignored.
1758 For finer control and match boundaries use the
1762 .It Ar / Ns Ar string
1763 All messages that contain
1765 in the subject field (case ignored).
1772 the string from the previous specification of that type is used again.
1774 .It Xo Op Ar @ Ns Ar name-list Ns
1777 All messages that contain the given case-insensitive search
1779 ession; if the \*(OPal regular expression (see
1781 support is available
1783 will be interpreted as (an extended) one if any of the
1785 (extended) regular expression characters is seen.
1787 .Ar @ Ns Ar name-list
1788 part is missing, the search is restricted to the subject field body,
1791 specifies a comma-separated list of header fields to search, as in
1793 .Dl '@to,from,cc@Someone i ought to know'
1795 In order to search for a string that includes a
1797 (commercial at) character the
1799 is effectively non-optional, but may be given as the empty string.
1800 Some special header fields may be abbreviated:
1814 respectively and case-insensitively.
1819 can be used to search in (all of) the header(s) of the message, and the
1828 can be used to perform full text searches \(en whereas the former
1829 searches only the body, the latter also searches the message header.
1831 This message specification performs full text comparison, but even with
1832 regular expression support it is almost impossible to write a search
1833 expression that savely matches only a specific address domain.
1834 To request that the content of the header is treated as a list of
1835 addresses, and to strip those down to the plain email address which the
1836 search expression is to be matched against, prefix the header name
1837 (abbreviation) with a tilde
1840 .Dl @~f@@a\e.safe\e.domain\e.match$
1843 All messages of state
1847 is one or multiple of the following colon modifiers:
1849 .Bl -tag -compact -width ".It Ar :M"
1854 Old messages (any not in state
1880 Messages marked as draft.
1882 \*(OP Messages classified as spam.
1884 \*(OP Messages with unsure spam classification.
1890 \*(OP IMAP-style SEARCH expressions may also be used.
1891 This addressing mode is available with all types of folders;
1892 \*(UA will perform the search locally as necessary.
1893 Strings must be enclosed by double quotes
1895 in their entirety if they contain white space or parentheses;
1896 within the quotes, only reverse solidus
1898 is recognized as an escape character.
1899 All string searches are case-insensitive.
1900 When the description indicates that the
1902 representation of an address field is used,
1903 this means that the search string is checked against both a list
1906 .Bd -literal -offset indent
1907 (\*qname\*q \*qsource\*q \*qlocal-part\*q \*qdomain-part\*q)
1912 and the addresses without real names from the respective header field.
1913 These search expressions can be nested using parentheses, see below for
1917 .Bl -tag -compact -width ".It Ar _n_u"
1918 .It Ar ( criterion )
1919 All messages that satisfy the given
1921 .It Ar ( criterion1 criterion2 ... criterionN )
1922 All messages that satisfy all of the given criteria.
1924 .It Ar ( or criterion1 criterion2 )
1925 All messages that satisfy either
1930 To connect more than two criteria using
1932 specifications have to be nested using additional parentheses,
1934 .Ql (or a (or b c)) ,
1938 .Ql ((a or b) and c) .
1941 operation of independent criteria on the lowest nesting level,
1942 it is possible to achieve similar effects by using three separate
1946 .It Ar ( not criterion )
1947 All messages that do not satisfy
1949 .It Ar ( bcc \*q Ns Ar string Ns Ar \*q )
1950 All messages that contain
1952 in the envelope representation of the
1955 .It Ar ( cc \*q Ns Ar string Ns Ar \*q )
1956 All messages that contain
1958 in the envelope representation of the
1961 .It Ar ( from \*q Ns Ar string Ns Ar \*q )
1962 All messages that contain
1964 in the envelope representation of the
1967 .It Ar ( subject \*q Ns Ar string Ns Ar \*q )
1968 All messages that contain
1973 .It Ar ( to \*q Ns Ar string Ns Ar \*q )
1974 All messages that contain
1976 in the envelope representation of the
1979 .It Ar ( header name \*q Ns Ar string Ns Ar \*q )
1980 All messages that contain
1985 .It Ar ( body \*q Ns Ar string Ns Ar \*q )
1986 All messages that contain
1989 .It Ar ( text \*q Ns Ar string Ns Ar \*q )
1990 All messages that contain
1992 in their header or body.
1993 .It Ar ( larger size )
1994 All messages that are larger than
1997 .It Ar ( smaller size )
1998 All messages that are smaller than
2002 .It Ar ( before date )
2003 All messages that were received before
2005 which must be in the form
2009 denotes the day of the month as one or two digits,
2011 is the name of the month \(en one of
2012 .Ql Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ,
2015 is the year as four digits, e.g.,
2019 All messages that were received on the specified date.
2020 .It Ar ( since date )
2021 All messages that were received since the specified date.
2022 .It Ar ( sentbefore date )
2023 All messages that were sent on the specified date.
2024 .It Ar ( senton date )
2025 All messages that were sent on the specified date.
2026 .It Ar ( sentsince date )
2027 All messages that were sent since the specified date.
2029 The same criterion as for the previous search.
2030 This specification cannot be used as part of another criterion.
2031 If the previous command line contained more than one independent
2032 criterion then the last of those criteria is used.
2036 .\" .Ss "On URL syntax and credential lookup" {{{
2037 .Ss "On URL syntax and credential lookup"
2039 \*(IN For accessing protocol-specific resources usage of Uniform
2040 Resource Locators (URL, RFC 1738) has become omnipresent.
2041 \*(UA expects and understands URLs in the following form;
2044 denote optional parts, optional either because there also exist other
2045 ways to define the information in question or because support of the
2046 part is protocol-specific (e.g.,
2048 is used by the IMAP protocol but not by POP3);
2053 are specified they must be given in URL percent encoded form (RFC 3986;
2059 .Dl PROTOCOL://[USER[:PASSWORD]@]server[:port][/path]
2062 Note that these \*(UA URLs most often don't conform to any real
2063 standard, but instead represent a normalized variant of RFC 1738 \(en
2064 they are not used in data exchange but only meant as a compact,
2065 easy-to-use way of defining and representing information in
2066 a well-known notation.
2069 Many internal variables of \*(UA exist in multiple versions, called
2070 variable chains for the rest of this document: the plain
2075 .Ql variable-USER@HOST .
2082 had been specified in the respective URL, otherwise it refers to the plain
2088 that had been found when doing the user chain lookup as is described
2091 will never be in URL percent encoded form, whether it came from an URL
2092 or not; i.e., variable chain name extensions of
2093 .Sx "INTERNAL VARIABLES"
2094 must not be URL percent encoded.
2097 For example, whether an hypothetical URL
2098 .Ql smtp://hey%3Ayou@our.house
2099 had been given that includes a user, or whether the URL was
2100 .Ql smtp://our.house
2101 and the user had been found differently, to lookup the variable chain
2102 .Va smtp-use-starttls
2103 \*(UA first looks for whether
2104 .Ql smtp-\:use-\:starttls-\:hey:you@our.house
2105 is defined, then whether
2106 .Ql smtp-\:use-\:starttls-\:our.house
2107 exists before finally ending up looking at the plain variable itself.
2110 \*(UA obeys the following logic scheme when dealing with the
2111 necessary credential information of an account:
2117 has been given in the URL the variables
2121 are looked up; if no such variable(s) can be found then \*(UA will,
2122 when enforced by the \*(OPal variables
2123 .Va netrc-lookup-HOST
2130 specific entry which provides a
2132 name: this lookup will only succeed if unambiguous (one possible matching
2135 It is possible to load encrypted
2140 If there is still no
2142 then \*(UA will fall back to the user who is supposed to run \*(UA,
2143 the identity of which has been fixated during \*(UA startup and is
2144 known to be a valid user on the current host.
2147 Authentication: unless otherwise noted this will lookup the
2148 .Va PROTOCOL-auth-USER@HOST , PROTOCOL-auth-HOST , PROTOCOL-auth
2149 variable chain, falling back to a protocol-specific default should this
2155 has been given in the URL, then if the
2157 has been found through the \*(OPal
2159 that may have already provided the password, too.
2160 Otherwise the variable chain
2161 .Va password-USER@HOST , password-HOST , password
2162 is looked up and used if existent.
2164 Afterwards the complete \*(OPal variable chain
2165 .Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup
2169 cache is searched for a password only (multiple user accounts for
2170 a single machine may exist as well as a fallback entry without user
2171 but with a password).
2173 If at that point there is still no password available, but the
2174 (protocols') chosen authentication type requires a password, then in
2175 interactive mode the user will be prompted on the terminal.
2180 S/MIME verification works relative to the values found in the
2184 header field(s), which means that the values of
2185 .Va smime-sign , smime-sign-cert , smime-sign-include-certs
2187 .Va smime-sign-message-digest
2188 will not be looked up using the
2192 chains from above but instead use the corresponding values from the
2193 message that is being worked on.
2194 In unusual cases multiple and different
2198 combinations may therefore be involved \(en on the other hand those
2199 unusual cases become possible.
2200 The usual case is as short as:
2203 .Dl set mta=smtp://USER:PASS@HOST smtp-use-starttls \e
2204 .Dl \ \ \ \ smime-sign smime-sign-cert=+smime.pair
2209 contains complete example configurations.
2212 .\" .Ss "On terminal control and line editor" {{{
2213 .Ss "On terminal control and line editor"
2215 \*(OP Terminal control will be realized through one of the standard
2217 libraries, either the
2219 or, alternatively, the
2221 both of which will be initialized to work with the environment variable
2223 Terminal control will enhance or enable interactive usage aspects, e.g.,
2224 .Sx "Coloured display" ,
2225 and extend behaviour of the Mailx-Line-Editor (MLE), which may learn the
2226 byte-sequences of keys like the cursor and function keys, and which will
2227 automatically enter the so-called
2229 alternative screen shall the terminal support it.
2230 The internal variable
2232 can be used to overwrite settings or to learn (correct(ed)) keycodes.
2233 Actual interaction with the chosen library can be disabled completely by
2234 setting the internal variable
2235 .Va termcap-disable ;
2237 will be queried regardless, even if the \*(OPal support for the
2238 libraries has not been enabled at configuration time.
2241 \*(OP The builtin \*(UA Mailx-Line-Editor (MLE) should work in all
2242 environments which comply to the ISO C standard
2244 and will support wide glyphs if possible (the necessary functionality
2245 had been removed from ISO C, but was included in
2247 Prevent usage of a line editor in interactive mode by setting the
2249 .Va line-editor-disable .
2250 Especially if the \*(OPal terminal control support is missing setting
2251 entries in the internal variable
2253 will help shall the MLE misbehave, see there for more.
2254 The MLE can support a little bit of
2260 feature is available then input from line editor prompts will be saved
2261 in a history list that can be searched in and be expanded from.
2262 Such saving can be prevented by prefixing input with any amount of
2264 Aspects of history, like allowed content and maximum size, as well as
2265 whether history shall be saved persistently, can be configured with the
2269 .Va history-gabby-persist
2274 The MLE supports a set of editing and control commands.
2275 By default (as) many (as possible) of these will be assigned to a set of
2276 single-letter control codes, which should work on any terminal (and can
2277 be generated by holding the
2279 key while pressing the key of desire, e.g.,
2283 command is available then the MLE commands can also be accessed freely
2284 by assigning the command name, which is shown in parenthesis in the list
2285 below, to any desired key-sequence, and the MLE will instead and also use
2287 to establish its builtin key bindings
2288 (more of them if the \*(OPal terminal control is available),
2289 an action which can then be suppressed completely by setting
2290 .Va line-editor-no-defaults .
2291 The following uses the
2293 ell-style quote notation that is documented in the introduction of
2295 combinations not mentioned either cause job control signals or don't
2296 generate a (unique) keycode:
2300 .Bl -tag -compact -width "Ql _M"
2302 Go to the start of the line
2303 .Pf ( Cd mle-go-home ) .
2306 Move the cursor backward one character
2307 .Pf ( Cd mle-go-bwd ) .
2310 Forward delete the character under the cursor;
2311 quits \*(UA if used on the empty line unless the
2314 .Pf ( Cd mle-del-fwd ) .
2317 Go to the end of the line
2318 .Pf ( Cd mle-go-end ) .
2321 Move the cursor forward one character
2322 .Pf ( Cd mle-go-fwd ) .
2325 Cancel current operation, full reset.
2326 If there is an active history search or tabulator expansion then this
2327 command will first reset that, reverting to the former line content;
2328 thus a second reset is needed for a full reset in this case
2329 .Pf ( Cd mle-reset ) .
2332 Backspace: backward delete one character
2333 .Pf ( Cd mle-del-bwd ) .
2337 Horizontal tabulator:
2338 try to expand the word before the cursor, also supporting \*(UA
2341 .Pf ( Cd mle-complete ) .
2343 .Cd mle-quote-rndtrip .
2347 commit the current line
2348 .Pf ( Cd mle-commit ) .
2351 Cut all characters from the cursor to the end of the line
2352 .Pf ( Cd mle-snarf-end ) .
2356 .Pf ( Cd mle-repaint ) .
2359 \*(OP Go to the next history entry
2360 .Pf ( Cd mle-hist-fwd ) .
2367 \*(OP Go to the previous history entry
2368 .Pf ( Cd mle-hist-bwd ) .
2371 Toggle roundtrip mode shell quotes, where produced,
2373 .Pf ( Cd mle-quote-rndtrip ) .
2374 This setting is temporary, and will be forgotten once the command line
2378 \*(OP Complete the current line from (the remaining) older history entries
2379 .Pf ( Cd mle-hist-srch-bwd ) .
2382 \*(OP Complete the current line from (the remaining) newer history entries
2383 .Pf ( Cd mle-hist-srch-fwd ) .
2386 Paste the snarf buffer
2387 .Pf ( Cd mle-paste ) .
2394 .Pf ( Cd mle-snarf-line ) .
2397 Prompts for a Unicode character (its hexadecimal number) to be inserted
2398 .Pf ( Cd mle-prompt-char ) .
2399 Note this command needs to be assigned to a single-letter control code
2400 in order to become recognized and executed during input of
2401 a key-sequence (only four single-letter control codes can be used for
2402 that shortcut purpose); this control code is special-treated and can't
2403 be part of any other sequence, because any occurrence will perform the
2405 function immediately.
2408 Cut the characters from the one preceding the cursor to the preceding
2410 .Pf ( Cd mle-snarf-word-bwd ) .
2413 Move the cursor forward one word boundary
2414 .Pf ( Cd mle-go-word-fwd ) .
2417 Move the cursor backward one word boundary
2418 .Pf ( Cd mle-go-word-bwd ) .
2421 Escape: reset a possibly used multibyte character input state machine
2422 and \*(OPally a lingering, incomplete key binding
2423 .Pf ( Cd mle-cancel ) .
2424 This command needs to be assigned to a single-letter control code in
2425 order to become recognized and executed during input of a key-sequence
2426 (only four single-letter control codes can be used for that shortcut
2428 This control code may also be part of a multi-byte sequence, but if
2429 a sequence is active and the very control code is currently also an
2430 expected input, then it will first be consumed by the active sequence.
2445 Cut the characters from the one after the cursor to the succeeding word
2447 .Pf ( Cd mle-snarf-word-fwd ) .
2457 this will immediately reset a possibly active search etc.
2461 ring the audible bell.
2465 .\" .Ss "Coloured display" {{{
2466 .Ss "Coloured display"
2468 \*(OP \*(UA can be configured to support a coloured display and font
2469 attributes by emitting ANSI / ISO 6429 SGR (select graphic rendition)
2471 Usage of colours and font attributes solely depends upon the
2472 capability of the detected terminal type that is defined by the
2473 environment variable
2475 and which can be fine-tuned by the user via the internal variable
2479 On top of what \*(UA knows about the terminal the boolean variable
2481 defines whether the actually applicable colour and font attribute
2482 sequences should also be generated when output is going to be paged
2483 through the external program defined by the environment variable
2488 This is not enabled by default because different pager programs need
2489 different command line switches or other configuration in order to
2490 support those sequences.
2491 \*(UA however knows about some widely used pagers and in a clean
2492 environment it is often enough to simply set
2494 please refer to that variable for more on this topic.
2499 is set then any active usage of colour and font attribute sequences
2500 is suppressed, but without affecting possibly established
2505 To define and control colours and font attributes a single multiplexer
2506 command family exists:
2508 shows or defines colour mappings for the given colour type (e.g.,
2511 can be used to remove mappings of a given colour type.
2512 Since colours are only available in interactive mode, it may make
2513 sense to conditionalize the colour setup by encapsulating it with
2516 .Bd -literal -offset indent
2517 if terminal && $features =@ +colour
2518 colour iso view-msginfo ft=bold,fg=green
2519 colour iso view-header ft=bold,fg=red "from,subject"
2520 colour iso view-header fg=red
2522 uncolour iso view-header from,subject
2523 colour iso view-header ft=bold,fg=magenta,bg=cyan
2524 colour 256 view-header ft=bold,fg=208,bg=230 subject,from
2525 colour mono view-header ft=bold
2526 colour mono view-header ft=bold,ft=reverse subject,from
2530 .\" }}} (DESCRIPTION)
2533 .\" .Sh COMMANDS {{{
2536 Each command is typed on a line by itself,
2537 and may take arguments following the command word.
2538 Command names may be abbreviated, in which case the first command that
2539 matches the given prefix will be used.
2542 can be used to show the list of all commands, either alphabetically
2543 sorted or in prefix search order (these don't match, also because the
2544 POSIX standard prescribes a set of abbreviations).
2545 \*(OPally the command
2549 when given an argument, will show a documentation string for the
2550 command matching the expanded argument, as in
2552 which should be a shorthand of
2554 Both commands support a more
2556 listing mode which includes the argument type of the command.
2559 For commands which take message lists as arguments, the next message
2560 forward that satisfies the command's requirements will be used shall no
2561 explicit message list have been specified.
2562 If there are no messages forward of the current message,
2563 the search proceeds backwards,
2564 and if there are no good messages at all,
2565 \*(UA shows an error message and aborts the command.
2566 \*(ID Non-message-list arguments can be quoted using the following methods:
2569 .Bl -bullet -compact -offset indent
2571 An argument can be enclosed between paired double-quotes
2576 any white space, shell word expansion, or reverse solidus characters
2577 (except as described next) within the quotes are treated literally as
2578 part of the argument.
2579 A double-quote will be treated literally within single-quotes and vice
2581 Inside such a quoted string the actually used quote character can be
2582 used nonetheless by escaping it with a reverse solidus
2588 An argument that is not enclosed in quotes, as above, can usually still
2589 contain space characters if those spaces are reverse solidus escaped, as in
2593 A reverse solidus outside of the enclosing quotes is discarded
2594 and the following character is treated literally as part of the argument.
2599 Some commands which don't take message-list arguments can also be
2600 prefixed with the special keyword
2602 to choose \*(INible argument quoting rules, and some new commands only
2603 support the new rules (without that keyword) and are flagged \*(NQ.
2604 In the future \*(UA will (mostly) use
2606 compatible argument parsing:
2607 Non-message-list arguments can be quoted using the following shell-style
2608 mechanisms: the escape character, single-quotes, double-quotes and
2609 dollar-single-quotes; any unquoted number sign
2611 that parses as a new token starts a comment that ends argument processing.
2612 The overall granularity of error reporting and diagnostics, also
2613 regarding function arguments and their content, will improve.
2617 .Bl -bullet -compact -offset indent
2619 The literal value of any character can be preserved by preceding it
2620 with the escape character reverse solidus
2624 will cause variable expansion of the given name: \*(UA
2625 .Sx "INTERNAL VARIABLES"
2628 (shell) variables can be accessed through this mechanism, brace
2629 enclosing the name is supported.
2632 Arguments which are enclosed in
2633 .Ql 'single-\:quotes'
2634 retain their literal value.
2635 A single-quote cannot occur within single-quotes.
2638 The literal value of all characters enclosed in
2639 .Ql \(dqdouble-\:quotes\(dq
2640 is retained, with the exception of dollar
2642 which will cause variable expansion, as above, backquote (grave accent)
2644 (which not yet means anything special), reverse solidus
2646 which will escape any of the characters dollar
2648 (to prevent variable expansion), backquote (grave accent)
2652 (to prevent ending the quote) and reverse solidus
2654 (to prevent escaping, i.e., to embed a reverse solidus character as-is),
2655 but has no special meaning otherwise.
2658 Arguments enclosed in
2659 .Ql $'dollar-\:single-\:quotes'
2660 extend normal single quotes in that reverse solidus escape sequences are
2661 expanded as follows:
2663 .Bl -tag -compact -width "Ql \eNNN"
2669 an escape character.
2671 an escape character.
2683 emits a reverse solidus character.
2687 double quote (escaping is optional).
2689 eight-bit byte with the octal value
2691 (one to three octal digits), optionally prefixed by an additional
2693 A 0 byte will suppress further output for the quoted argument.
2695 eight-bit byte with the hexadecimal value
2697 (one or two hexadecimal characters).
2698 A 0 byte will suppress further output for the quoted argument.
2700 the Unicode / ISO-10646 character with the hexadecimal codepoint value
2702 (one to eight hexadecimal digits) \(em note that Unicode defines the
2703 maximum codepoint to be ever supported as
2708 This escape is only supported in locales which support Unicode (see
2709 .Sx "Character sets" ) ,
2710 in other cases the sequence will remain unexpanded unless the given code
2711 point is ASCII compatible or can be represented in the current locale.
2712 The character NUL will suppress further output for the quoted argument.
2716 except it takes only one to four hexadecimal digits.
2721 This is a mechanism that allows usage of the non-printable (ASCII and
2722 compatible) control codes 0 to 31: to be able to create a printable
2723 representation the numeric value 64 is added to the control code of
2724 desire, and the resulting ASCII character set code point is then
2725 printed, e.g., BEL is
2726 .Ql 7 + 64 = 71 = G .
2727 Often circumflex notation is used for the visualization purpose, e.g,
2729 but the reverse solid notation has been standardized:
2731 The control code NUL
2733 ends argument processing without producing further output.
2735 Non-standard extension: expand the given variable name, as above.
2736 Brace enclosing the name is supported.
2738 Not yet supported, just to raise awareness: Non-standard extension.
2744 .Sy Compatibility notes:
2745 \*(ID Note these are new mechanisms which are not supported by all
2747 Round-tripping (feeding in things shown in list modes again) are not yet
2748 stable or possible at all.
2749 On new-style command lines it is wise to quote semicolon
2753 characters in order to ensure upward compatibility: the author would
2754 like to see things like
2755 .Ql ? echo $'trouble\etahead' | cat >> in_the_shell.txt
2757 .Ql ? top 2 5 10; type 3 22
2759 Before \*(UA will switch entirely to shell-style argument parsing there
2760 will be a transition phase where using
2762 will emit obsoletion warnings.
2764 .Bd -literal -offset indent
2765 echo 'Quotes '${HOME}' and 'tokens" differ!"# no comment
2766 echo Quotes ${HOME} and tokens differ! # comment
2767 echo Don"'"t you worry$'\ex21' The sun shines on us. $'\eu263A'
2771 In any event an unquoted reverse solidus at the end of a command line is
2772 discarded and the next line continues the command.
2773 \*(ID Note that line continuation is handled before the above parsing is
2774 applied, i.e., the parsers documented above will see merged lines.
2775 Filenames, where expected, are subsequently subjected to the following
2776 transformations, in sequence:
2779 .Bl -bullet -compact -offset indent
2781 If the filename begins with an unquoted plus sign, and the
2783 variable is defined,
2784 the plus sign will be replaced by the value of the
2786 variable followed by a solidus.
2789 variable is unset or is set to null, the filename will be unchanged.
2792 Meta expansions are applied to the filename: a leading tilde
2794 character will be replaced by the expansion of
2796 except when followed by a valid user name, in which case the home
2797 directory of the given user is used instead.
2802 will be replaced by the expansion of the variable, if possible; \*(UA
2803 .Sx "INTERNAL VARIABLES"
2806 (shell) variables can be accessed through this mechanism, and the usual
2807 escape mechanism has to be applied to prevent interpretation.
2808 If the fully expanded filename results in multiple pathnames and the
2809 command is expecting only one file, an error results.
2811 In interactive context, in order to allow simple value acceptance (via
2813 arguments will usually be displayed in a properly quoted form, e.g., a file
2814 .Ql diet\e is \ecurd.txt
2816 .Ql 'diet\e is \ecurd.txt' .
2820 The following commands are available:
2822 .Bl -tag -width ".Ic _ccount"
2829 ) command which follows.
2833 The comment-command causes the entire line to be ignored.
2835 this really is a normal command which' purpose is to discard its
2838 indicating special character, which means that, e.g., trailing comments
2839 on a line are not possible.
2843 Goes to the next message in sequence and types it
2849 Display the preceding message, or the n'th previous message if given
2850 a numeric argument n.
2854 Show the current message number (the
2859 Show a brief summary of commands.
2862 output is available.
2863 \*(OP Given an argument a synopsis for the command in question is
2864 shown instead; commands can be abbreviated in general and this command
2865 can be used to see the full expansion of an abbreviation including the
2866 synopsis, try, e.g.,
2871 and see how the output changes.
2881 Interprets the remainder of the word as a macro name and passes it
2886 is a shorter synonym for
2887 .Ql call Ar mymacro .
2891 (ac) Creates, selects or lists (an) account(s).
2892 Accounts are special incarnations of
2894 macros and group commands and variable settings which together usually
2895 arrange the environment for the purpose of creating an email account.
2896 Different to normal macros settings which are covered by
2898 \(en here by default enabled! \(en will not be reverted before the
2903 (case-insensitive) always exists, and all but it can be deleted via
2906 Without arguments a listing of all defined accounts is shown.
2907 With one argument the given account is activated: the system
2909 of that account will be activated (as via
2911 and a possibly installed
2914 The two argument form is identical to defining a macro as via
2916 .Bd -literal -offset indent
2918 set folder=~/mail inbox=+syste.mbox record=+sent.mbox
2919 set from='myname@myisp.example (My Name)'
2920 set mta=smtp://mylogin@smtp.myisp.example
2926 (a) With no arguments, shows all currently-defined aliases.
2927 With one argument, shows that alias.
2928 With more than one argument,
2929 creates a new alias or appends to an existing one.
2931 can be used to delete aliases.
2935 (alt) Manage a list of alternate addresses / names of the active user,
2936 members of which will be removed from recipient lists when replying to
2939 variable is not set).
2940 If arguments are given the set of alternate names is replaced by them,
2941 without arguments the current set is displayed.
2945 Takes a message list and marks each message as having been answered.
2946 This mark has no technical meaning in the mail system;
2947 it just causes messages to be marked in the header summary,
2948 and makes them specially addressable.
2953 \*(OP\*(NQ The bind command extends the MLE (see
2954 .Sx "On terminal control and line editor" )
2955 with freely configurable key bindings.
2956 With one argument all bindings for the given context are shown,
2957 specifying an asterisk
2959 will show the bindings of all contexts; a more verbose listing will be
2960 produced if either of
2965 With two or more arguments a binding is (re)established:
2966 the first argument is the context to which the binding shall apply,
2967 the second argument is a comma-separated list of the
2969 which form the binding, and any remaining arguments form the expansion.
2970 To indicate that a binding shall not be auto-committed, but that the
2971 expansion shall instead be furtherly editable by the user, an at-sign
2973 (that will be removed) can be placed last in the expansion, from which
2974 leading and trailing whitespace will finally be removed.
2977 Contexts define when a binding applies, i.e., a binding won't be seen
2978 unless the context for which it is defined for is currently active.
2979 This is not true for the binding
2981 which always applies, but which will be searched secondarily to a more
2982 specialized context and may thus have some or all of its key bindings
2983 transparently replaced by equal bindings of more specialized contexts.
2984 The available contexts are
2986 which always applies, and
2988 which applies to compose-mode.
2992 which form the binding are specified as a comma-separated list of
2993 byte-sequences, where each list entry corresponds to one key(press).
2994 \*(OPally a list entry may, indicated by a leading colon character
2996 also refer to the name of a terminal capability;
2997 several dozen names will be compiled into \*(UA and may be specified
3000 or, if existing, by their
3002 name, regardless of the actually used terminal control library.
3003 It is however possible to use any capability, as long as the name is
3004 resolvable by the control library or defined in the internal variable
3006 Input sequences are not case-normalized, so that an exact match is
3007 required to update or remove a binding.
3010 .Bd -literal -offset indent
3011 bind base $'\eE',d mle-snarf-word-fwd # Esc(ape)
3012 bind base $'\eE',$'\ec?' mle-snarf-word-bwd # Esc, Delete
3013 bind compose :kf1 ~e
3014 bind base $'\ecA',:khome,w 'echo An editable binding@'
3015 bind base a,b,c rm -rf / @ # Another editable binding
3019 Note that the entire comma-separated list is first parsed (over) as a
3020 shell-token with whitespace as the field separator, before being parsed
3021 and expanded for real with comma as the field separator, therefore
3022 whitespace needs to be properly quoted:
3023 shell-style quoting is documented in the introduction of
3025 Using Unicode reverse solidus escape sequences renders a binding
3026 defunctional if the locale doesn't support Unicode (see
3027 .Sx "Character sets" ) ,
3028 and using terminal capabilities does so if no terminal control support
3029 is (currently) available.
3032 The following terminal capability names are builtin and can be used in
3034 or (if available) the two-letter
3036 notation regardless of the actually used library.
3037 See the respective manual for a list of capabilities.
3040 can be used to show all the capabilities of
3042 or the given terminal type;
3045 flag will also show supported (non-standard) extensions.
3048 .Bl -tag -compact -width kcuuf_or_kcuuf
3049 .It Cd kbs Ns \0or Cd kb
3051 .It Cd kdch1 Ns \0or Cd kD
3053 .It Cd kDC Ns \0or Cd *4
3054 \(em shifted variant.
3055 .It Cd kel Ns \0or Cd kE
3056 Clear to end of line.
3057 .It Cd kext Ns \0or Cd @9
3059 .It Cd kich1 Ns \0or Cd kI
3061 .It Cd kIC Ns \0or Cd #3
3062 \(em shifted variant.
3063 .It Cd khome Ns \0or Cd kh
3065 .It Cd kHOM Ns \0or Cd #2
3066 \(em shifted variant.
3067 .It Cd kend Ns \0or Cd @7
3069 .It Cd knp Ns \0or Cd kN
3071 .It Cd kpp Ns \0or Cd kP
3073 .It Cd kcub1 Ns \0or Cd kl
3074 Left cursor (with more modifiers: see below).
3075 .It Cd kLFT Ns \0or Cd #4
3076 \(em shifted variant.
3077 .It Cd kcuf1 Ns \0or Cd kr
3078 Right cursor (ditto).
3079 .It Cd kRIT Ns \0or Cd %i
3080 \(em shifted variant.
3081 .It Cd kcud1 Ns \0or Cd kd
3082 Down cursor (ditto).
3084 \(em shifted variant (only terminfo).
3085 .It Cd kcuu1 Ns \0or Cd ku
3088 \(em shifted variant (only terminfo).
3089 .It Cd kf0 Ns \0or Cd k0
3091 Add one for each function key up to
3096 .It Cd kf10 Ns \0or Cd k;
3098 .It Cd kf11 Ns \0or Cd F1
3100 Add one for each function key up to
3108 Some terminals support key-modifier combination extensions, e.g.,
3110 For example, the delete key,
3112 in its shifted variant, the name is mutated to
3114 then a number is appended for the states
3126 .Ql Shift+Alt+Control
3128 The same for the left cursor key,
3130 .Cd KLFT , KLFT3 , KLFT4 , KLFT5 , KLFT6 , KLFT7 , KLFT8 .
3133 Key bindings can be removed with the command
3135 It is advisable to use an initial escape or other control character (e.g.,
3137 for bindings which describe user key combinations (as opposed to purely
3138 terminal capability based ones), in order to avoid ambiguities whether
3139 input belongs to key sequences or not; it also reduces search time.
3142 may help shall keys and sequences be falsely recognized.
3147 Calls a macro that has been created via
3152 (ch) Change the working directory to
3154 or the given argument.
3160 \*(OP Only applicable to S/MIME signed messages.
3161 Takes a message list and a file name and saves the certificates
3162 contained within the message signatures to the named file in both
3163 human-readable and PEM format.
3164 The certificates can later be used to send encrypted messages to the
3165 respective message senders by setting
3166 .Va smime-encrypt-USER@HOST
3171 (ch) Change the working directory to
3173 or the given argument.
3179 Only applicable to threaded mode.
3180 Takes a message list and makes all replies to these messages invisible
3181 in header summaries, unless they are in state
3187 \*(OP\*(NQ Manage colour mappings for the type of colour given as the
3188 (case-insensitive) first argument, which must be one of
3190 for 256-colour terminals,
3195 for the standard 8-colour ANSI / ISO 6429 color palette and
3199 for monochrome terminals.
3200 Monochrome terminals cannot deal with colours, but only (some) font
3204 Without further arguments the list of all currently defined mappings
3205 for the given colour type is shown (as a special case giving
3209 will iterate over all types in order).
3210 Otherwise the second argument defines the mappable slot, the third
3211 argument a (comma-separated list of) colour and font attribute
3212 specification(s), and the optional fourth argument can be used to
3213 specify a precondition: if conditioned mappings exist they are tested in
3214 (creation) order unless a (case-insensitive) match has been found, and
3215 the default mapping (if any has been established) will only be chosen as
3217 The types of precondition available depend on the mappable slot, the
3218 following of which exist:
3221 Mappings prefixed with
3223 are used for the \*(OPal builtin Mailx-Line-Editor (MLE, see
3224 .Sx "On terminal control and line editor" )
3225 and don't support preconditions.
3227 .Bl -tag -compact -width view-partinfo
3229 This mapping is used for the position indicator that is visible when
3230 a line cannot be fully displayed on the screen.
3237 Mappings prefixed with
3239 are used in header summaries, and they all understand the preconditions
3241 (the current message) and
3243 for elder messages (only honoured in conjunction with
3244 .Va datefield-markout-older ) .
3246 .Bl -tag -compact -width view-partinfo
3248 This mapping is used for the
3250 that can be created with the
3254 formats of the variable
3257 For the complete header summary line except the
3259 and the thread structure.
3261 For the thread structure which can be created with the
3263 format of the variable
3268 Mappings prefixed with
3270 are used when displaying messages.
3272 .Bl -tag -compact -width view-partinfo
3274 This mapping is used for so-called
3276 lines, which are MBOX file format specific header lines.
3279 A comma-separated list of headers to which the mapping applies may be
3280 given as a precondition; if the \*(OPal regular expression support is
3281 available then if any of the
3283 (extended) regular expression characters is seen the precondition will
3284 be evaluated as (an extended) one.
3286 For the introductional message info line.
3287 .It Cd view-partinfo
3288 For MIME part info lines.
3292 The following (case-insensitive) colour definitions and font attributes
3293 are understood, multiple of which can be specified in a comma-separated
3303 It is possible (and often applicable) to specify multiple font
3304 attributes for a single mapping.
3307 foreground colour attribute:
3317 To specify a 256-color mode a decimal number colour specification in
3318 the range 0 to 255, inclusive, is supported, and interpreted as follows:
3320 .Bl -tag -compact -width "999 - 999"
3322 the standard ISO 6429 colors, as above.
3324 high intensity variants of the standard colors.
3326 216 colors in tuples of 6.
3328 grayscale from black to white in 24 steps.
3330 .Bd -literal -offset indent
3332 fg() { printf "\e033[38;5;${1}m($1)"; }
3333 bg() { printf "\e033[48;5;${1}m($1)"; }
3335 while [ $i -lt 256 ]; do fg $i; i=$(($i + 1)); done
3336 printf "\e033[0m\en"
3338 while [ $i -lt 256 ]; do bg $i; i=$(($i + 1)); done
3339 printf "\e033[0m\en"
3343 background colour attribute (see
3345 for possible values).
3349 Mappings may be removed with the command
3351 For a generic overview see the section
3352 .Sx "Coloured display" .
3357 (C) Copy messages to files whose names are derived from the author of
3358 the respective message and don't mark them as being saved;
3359 otherwise identical to
3364 (c) Copy messages to the named file and don't mark them as being saved;
3365 otherwise identical to
3370 \*(NQ With no arguments, shows all currently-defined custom headers.
3371 With one argument, shows that custom header.
3372 With more than one argument, creates a new or replaces an existing
3373 custom header with the name given as the first argument, the content of
3374 which being defined by the concatenated remaining arguments.
3376 can be used to delete custom headers.
3377 \*(ID Overwriting of automatically managed headers is neither supported
3379 Defined custom headers will be injected into newly composed or forwarded
3382 .Dl customhdr OpenPGP id=12345678; url=http://www.YYY.ZZ
3386 may also be used to inject custom headers; it is covered by
3391 Show the name of the current working directory.
3395 \*(OP For unencrypted messages this command is identical to
3397 Encrypted messages are first decrypted, if possible, and then copied.
3401 \*(OP For unencrypted messages this command is identical to
3403 Encrypted messages are first decrypted, if possible, and then copied.
3407 Without arguments the current list of macros, including their content,
3408 is shown, otherwise a macro is defined.
3409 A macro definition is a sequence of commands in the following form:
3410 .Bd -literal -offset indent
3419 A defined macro can be invoked explicitly by using the
3423 commands, or implicitly if a macro hook is triggered, e.g., a
3425 Note that interpretation of
3427 depends on how (i.e.,
3429 normal macro, folder hook, hook, account switch) the macro is invoked.
3430 Macros can be deleted via
3434 Macro behaviour, including option localization, will change in v15.
3435 Please be aware of that and possibly embed a version check in a resource
3440 (d) Marks the given message list as
3442 Deleted messages will neither be saved in
3444 nor will they be available for most other commands.
3456 Deletes the current message and displays the next message.
3457 If there is no next message, \*(UA says
3464 up or down by one message when given
3468 argument, respectively.
3472 Takes a message list and marks each given message as a draft.
3473 This mark has no technical meaning in the mail system;
3474 it just causes messages to be marked in the header summary,
3475 and makes them specially addressable.
3479 (ec) Echoes its arguments after applying
3481 expansions and filename transformations, as documented for
3486 (e) Point the text editor (as defined in
3488 at each message from the given list in turn.
3489 Modified contents are discarded unless the
3496 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3497 conditional \(em if the condition of a preceding
3499 was false, check the following condition and execute the following block
3500 if it evaluates true.
3505 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3506 conditional \(em if none of the conditions of the preceding
3510 commands was true, the
3516 (en) Marks the end of an
3517 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3518 conditional execution block.
3523 \*(NQ \*(UA has a strict notion about which variables are
3524 .Sx "INTERNAL VARIABLES"
3525 and which are managed in the program
3527 Since some of the latter are a vivid part of \*(UAs functioning,
3528 however, they are transparently integrated into the normal handling of
3529 internal variables via
3533 To integrate other environment variables of choice into this
3534 transparent handling, and also to export internal variables into the
3535 process environment where they normally are not, a
3537 needs to become established with this command, as in, e.g.,
3540 .Dl environ link PERL5LIB from TZ
3543 Afterwards changing such variables with
3545 will cause automatic updates of the program environment, and therefore
3546 be inherited by newly created child processes.
3547 Sufficient system support provided (it was in BSD as early as 1987, and
3548 is standardized since Y2K) removing such variables with
3550 will remove them also from the program environment, but in any way
3551 the knowledge they ever have been
3554 Note this implies that
3556 may cause loss of links.
3561 will remove an existing link, but leaves the variables as such intact.
3562 Additionally the subcommands
3566 are provided, which work exactly the same as the documented commands
3570 but (additionally) link the variable(s) with the program environment and
3571 thus immediately export them to, or remove them from (if possible),
3572 respectively, the program environment.
3577 \*(OP Since \*(UA uses the console as a user interface it can happen
3578 that messages scroll by too fast to become recognized.
3579 Optionally an error message ring queue is available which stores
3580 duplicates of any error message and notifies the user in interactive
3581 sessions whenever a new error has occurred.
3582 The queue is finite: if its maximum size is reached any new message
3583 replaces the eldest.
3586 can be used to manage this message queue: if given
3588 or no argument the queue will be displayed and cleared,
3590 will only clear all messages from the queue.
3594 (ex or x) Exit from \*(UA without changing the active mailbox and skip
3595 any saving of messages in
3597 as well as a possibly tracked line editor history file.
3603 but open the mailbox readonly.
3607 (fi) The file command switches to a new mailbox.
3608 Without arguments it shows status information of the current mailbox.
3609 If an argument is given, it will write out changes (such as deletions)
3610 the user has made and open a new mailbox.
3611 Some special conventions are recognized for the
3615 .Bl -tag -compact -offset indent -width ".Ar %:__lespec"
3617 (number sign) means the previous file,
3619 (percent sign) means the invoking user's system mailbox, which either
3620 is the (itself expandable)
3622 if that is set, the standardized absolute pathname indicated by
3624 if that is set, or a builtin compile-time default otherwise.
3626 means the primary system mailbox of
3628 (and never the value of
3630 regardless of its actual setting),
3632 (ampersand) means the invoking user's
3642 expands to the same value as
3644 but the file is handled as a primary system mailbox by, e.g., the
3648 commands, meaning that messages that have been read in the current
3649 session will be moved to the
3651 mailbox instead of simply being flagged as read.
3654 If the name matches one of the strings defined with the command
3656 it is replaced by its long form and expanded.
3657 If the name ends with
3662 it is treated as being compressed with
3667 respectively, and transparently handled through an intermediate
3668 (un)compression step (using a temporary file) with the according
3669 facility, sufficient support provided.
3670 Likewise, if the named file doesn't exist, but a file with one of the
3671 mentioned compression extensions does, then the name is automatically
3672 expanded and the compressed file is used.
3674 Otherwise, if the name ends with an extension for which
3675 .Va file-hook-load-EXTENSION
3677 .Va file-hook-save-EXTENSION
3678 variables are set, then the given hooks will be used to load and save
3680 and \*(UA will work with an intermediate temporary file.
3682 MBOX files (flat file-based mailboxes) are generally locked during file
3683 operations in order to avoid inconsistencies due to concurrent
3685 \*(OPal Mailbox files which \*(UA treats as the system
3688 and primary mailboxes will also be protected by so-called dotlock
3689 files, the traditional way of mail spool file locking: for any file
3693 will be created for the duration of the synchronization \(em
3694 as necessary a privilege-separated dotlock child process will be used
3695 to accommodate for necessary privilege adjustments in order to create
3696 the dotlock file in the same directory
3697 and with the same user and group identities as the file of interest.
3701 refers to a directory with the subdirectories
3706 then it is treated as a folder in
3708 format; \*(ID the variable
3710 can be used to control the format of yet non-existent folders.
3713 .Dl \*(IN protocol://[user[:password]@]host[:port][/path]
3714 .Dl \*(OU protocol://[user@]host[:port][/path]
3716 is taken as an Internet mailbox specification.
3717 The \*(OPally supported protocols are
3721 (POP3 with SSL/TLS encrypted transport).
3724 part is valid only for IMAP; there it defaults to
3726 Also see the section
3727 .Sx "On URL syntax and credential lookup" .
3731 contains special characters, in particular
3735 they must be escaped in URL notation \(en the command
3737 can be used to show the necessary conversion.
3741 Takes a message list and marks the messages as
3743 ged for urgent/special attention.
3744 This mark has no technical meaning in the mail system;
3745 it just causes messages to be highlighted in the header summary,
3746 and makes them specially addressable.
3755 With no arguments, list the names of the folders in the folder directory.
3756 With an existing folder as an argument,
3757 lists the names of folders below the named folder.
3763 but saves the message in a file named after the local part of the first
3764 recipient's address (instead of in
3771 but saves the message in a file named after the local part of the first
3772 recipient's address (instead of in
3779 but responds to all recipients regardless of the
3784 .It Ic followupsender
3787 but responds to the sender only regardless of the
3803 (f) Takes a list of message specifications and displays a summary of
3804 their message headers, exactly as via
3806 An alias of this command is
3809 .Sx "Specifying messages" .
3815 but saves the message in a file named after the local part of the
3816 recipient's address (instead of in
3821 Takes a message and the address of a recipient
3822 and forwards the message to him.
3823 The text of the original message is included in the new one,
3824 with the value of the
3826 variable preceding it.
3831 commands specify which header fields are included in the new message.
3832 Only the first part of a multipart message is included unless the
3833 .Va forward-as-attachment
3837 is set recipient addresses will be stripped from comments, names etc.
3841 Specifies which header fields are to be ignored with the command
3843 This command has no effect when the
3844 .Va forward-as-attachment
3849 Specifies which header fields are to be retained with the command
3854 This command has no effect when the
3855 .Va forward-as-attachment
3860 Define or list command aliases, so-called ghosts.
3861 Without arguments a list of all currently known aliases is shown.
3862 With one argument the expansion of the given alias is shown.
3863 With two or more arguments a command alias is defined or updated: the
3864 first argument is the name under which the remaining command line should
3865 be accessible, the content of which can be just about anything.
3866 A ghost can be used everywhere a normal command can be used, but always
3867 takes precedence; any arguments that are given to the command alias are
3868 joined onto the alias content, and the resulting string forms the
3869 command line that is, in effect, executed.
3872 .Bd -literal -offset indent
3874 `ghost': no such alias: "xx"
3877 ghost xx "echo hello,"
3886 (h) Show the current group of headers, the size of which depends on
3889 and the style of which can be adjusted with the variable
3891 If a message-specification is given the group of headers containing the
3892 first message therein is shown and the message at the top of the screen
3907 the list of history entries;
3910 argument selects and shows the respective history entry \(en
3913 to accept it, and the history entry will become the new history top.
3914 The default mode if no arguments are given is
3921 Takes a message list and marks each message therein to be saved in the
3926 Does not override the
3929 \*(UA deviates from the POSIX standard with this command, because a
3931 command issued after
3933 will display the following message, not the current one.
3938 (i) Part of the nestable
3939 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3940 conditional execution construct \(em if the given condition is true then
3941 the encapsulated block is executed.
3942 POSIX only supports the (case-insensitive) conditions
3947 end, all remaining conditions are non-portable extensions; note that
3948 falsely specified conditions cause the execution of the entire
3949 conditional construct until the (matching) closing
3951 command to be suppressed.
3952 The syntax of the nestable
3954 conditional execution construct requires that each condition and syntax
3955 element is surrounded by whitespace.
3957 .Bd -literal -offset indent
3966 The (case-insensitive) condition
3968 erminal will evaluate to true if the standard input is a terminal, i.e.,
3969 in interactive sessions.
3970 Another condition can be any boolean value (see the section
3971 .Sx "INTERNAL VARIABLES"
3972 for textual boolean representations) to mark an enwrapped block as
3975 .Dq always execute .
3976 It is possible to check
3977 .Sx "INTERNAL VARIABLES"
3980 variables for existence or compare their expansion against a user given
3981 value or another variable by using the
3983 .Pf ( Dq variable next )
3984 conditional trigger character;
3985 a variable on the right hand side may be signalled using the same
3987 The variable names may be enclosed in a pair of matching braces.
3990 The available comparison operators are
3994 (less than or equal to),
4000 (greater than or equal to),
4004 (is substring of) and
4006 (is not substring of).
4007 The values of the left and right hand side are treated as strings and
4008 are compared 8-bit byte-wise, ignoring case according to the rules of
4009 the US-ASCII encoding (therefore, dependent on the active locale,
4010 possibly producing false results for strings in the locale encoding).
4011 Except for the substring checks the comparison will instead be performed
4012 arithmetically if both, the user given value as well as the variable
4013 content, can be parsed as numbers (integers).
4014 An unset variable is treated as the empty string.
4017 When the \*(OPal regular expression support is available, the additional
4023 They treat the right hand side as an extended regular expression that is
4024 matched case-insensitively and according to the active
4026 locale, meaning that strings in the locale encoding should be matched
4030 Conditions can be joined via AND-OR lists (where the AND operator is
4032 and the OR operator is
4034 which have equal precedence and will be evaluated with left
4035 associativity, thus using the same syntax that is known for the
4037 It is also possible to form groups of conditions and lists by enclosing
4038 them in pairs of brackets
4039 .Ql [\ \&.\&.\&.\ ] ,
4040 which may be interlocked within each other, and also be joined via
4044 The results of individual conditions and entire groups may be modified
4045 via unary operators: the unary operator
4047 will reverse the result.
4049 .Bd -literal -offset indent
4053 if $ttycharset == "UTF-8"
4054 echo *ttycharset* is set to UTF-8, case-insensitively
4058 echo These two variables are equal
4060 if $version-major >= 15
4061 echo Running a new version..
4062 if $features =@ +regex
4063 if $TERM =~ "^xterm\&.*"
4064 echo ..in an X terminal
4067 if [ [ true ] && [ [ ${debug} ] || [ $verbose ] ] ]
4070 if true && $debug || ${verbose}
4071 echo Left associativity, as is known from the shell
4073 if ! ! true && ! [ ! $debug && ! $verbose ]
4074 echo Unary operator support
4082 Without arguments the list of ignored header fields is shown,
4083 otherwise the given list of header fields is added to the ignore list:
4084 Header fields in the ignore list are not shown on the terminal when
4085 a message is displayed.
4086 To display a message in its entirety, use the commands
4097 Shows the names of all available commands, alphabetically sorted.
4098 If given any non-whitespace argument the list will be shown in the order
4099 in which command prefixes are searched.
4102 output is available.
4106 This command can be used to localize changes to variables, meaning that
4107 their state will be reverted to the former one once the covered scope
4109 It can only be used inside of macro definition blocks introduced by
4113 and is interpreted as a boolean (string, see
4114 .Sx "INTERNAL VARIABLES" ) ;
4117 of an account is left once it is switched off again.
4118 .Bd -literal -offset indent
4119 define temporary_settings {
4134 enables change localization and calls
4136 which explicitly resets localization, then any value changes within
4138 will still be reverted by
4140 \*(ID Once the outermost level, the one which enabled localization
4141 first, is left, but no earlier, all adjustments will be unrolled.
4142 \*(ID Likewise worth knowing, if in this example
4144 changes to a different
4146 which sets some variables that are yet covered by localizations, their
4147 scope will be extended, and in fact leaving the
4149 will (thus) restore settings in (likely) global scope which actually
4150 were defined in a local, private context.
4154 Reply to messages that come in via known
4157 .Pf ( Ic mlsubscribe )
4158 mailing lists, or pretend to do so (see
4159 .Sx "Mailing lists" ) :
4162 functionality this will actively resort and even remove message
4163 recipients in order to generate a message that is supposed to be sent to
4165 For example it will also implicitly generate a
4166 .Ql Mail-Followup-To:
4167 header if that seems useful, regardless of the setting of the variable
4174 but saves the message in a file named after the local part of the first
4175 recipient's address (instead of in
4180 (m) Takes a (list of) recipient address(es) as (an) argument(s),
4181 or asks on standard input if none were given;
4182 then collects the remaining mail content and sends it out.
4186 (mb) The given message list is to be sent to
4188 when \*(UA is quit; this is the default action unless the
4191 \*(ID This command can only be used in a primary system mailbox (see
4196 Without any arguments the content of the MIME type cache will displayed.
4197 Otherwise each argument defines a complete MIME type specification of
4198 a type that shall be added (prepended) to the cache.
4199 In any event MIME type sources are loaded first as necessary \(en
4200 .Va mimetypes-load-control
4201 can be used to fine-tune which sources are actually loaded.
4202 Refer to the section on
4203 .Sx "The mime.types files"
4204 for more on MIME type specifications and this topic in general.
4205 MIME type unregistration and cache resets can be triggered with
4210 Without arguments the list of all currently defined mailing lists
4211 (and their attributes, if any) is shown; a more verbose listing will be
4212 produced if either of
4217 Otherwise all given arguments (which need not be quoted except for
4218 whitespace) will be added and henceforth be recognized as mailing lists.
4219 Mailing lists may be removed via the command
4222 If the \*(OPal regular expression support is available then mailing
4223 lists may also be specified as (extended) regular expressions (see
4229 Without arguments the list of all currently defined mailing lists which
4230 have a subscription attribute is shown; a more verbose listing will be
4231 produced if either of
4236 Otherwise this attribute will be set for all given mailing lists,
4237 newly creating them as necessary (as via
4239 Subscription attributes may be removed via the command
4248 but moves the messages to a file named after the local part of the
4249 sender address of the first message (instead of in
4256 but marks the messages for deletion if they were transferred
4263 but also displays ignored header fields and all MIME parts.
4271 on the given messages, even in non-interactive mode and as long as the
4272 standard output is a terminal.
4278 \*(OP When used without arguments or if
4280 has been given the content of the
4282 cache is shown, loading it first as necessary.
4285 then the cache will only be initialized and
4287 will remove its contents.
4288 Note that \*(UA will try to load the file only once, use
4289 .Ql Ic \&\&netrc Ns \:\0\:clear
4290 to unlock further attempts.
4295 .Sx "On URL syntax and credential lookup" ;
4297 .Sx "The .netrc file"
4298 documents the file format in detail.
4302 Checks for new mail in the current folder without committing any changes
4304 If new mail is present, a message is shown.
4308 the headers of each new message are also shown.
4309 This command is not available for all mailbox types.
4317 Goes to the next message in sequence and types it.
4318 With an argument list, types the next matching message.
4332 If the current folder is accessed via a network connection, a
4334 command is sent, otherwise no operation is performed.
4340 but also displays ignored header fields and all MIME parts.
4348 on the given messages, even in non-interactive mode and as long as the
4349 standard output is a terminal.
4357 but also pipes ignored header fields and all parts of MIME
4358 .Ql multipart/alternative
4363 (pi) Takes a message list and a shell command
4364 and pipes the messages through the command.
4365 Without an argument the current message is piped through the command
4372 every message is followed by a formfeed character.
4393 (q) Terminates the session, saving all undeleted, unsaved messages in
4396 preserving all messages marked with
4400 or never referenced in the system
4402 and removing all other messages from the primary system mailbox.
4403 If new mail has arrived during the session,
4405 .Dq You have new mail
4407 If given while editing a mailbox file with the command line flag
4409 then the edit file is rewritten.
4410 A return to the shell is effected,
4411 unless the rewrite of edit file fails,
4412 in which case the user can escape with the exit command.
4426 Removes the named files or directories.
4427 If a name refer to a mailbox, e.g., a Maildir mailbox, then a mailbox
4428 type specific removal will be performed, deleting the complete mailbox.
4429 The user is asked for confirmation in interactive mode.
4433 Takes the name of an existing folder
4434 and the name for the new folder
4435 and renames the first to the second one.
4436 Both folders must be of the same type.
4440 (R) Reply to originator.
4441 Does not reply to other recipients of the original message.
4443 will exchange this command with
4447 is set the recipient address will be stripped from comments, names etc.
4451 (r) Take a message and group-responds to it by addressing the sender
4454 .Va followup-to-honour ,
4457 .Va recipients-in-cc
4458 influence response behaviour.
4461 offers special support for replying to mailing lists.
4464 is set recipient addresses will be stripped from comments, names etc.
4477 but initiates a group-reply regardless of the value of
4484 but responds to the sender only regardless of the value of
4491 but does not add any header lines.
4492 This is not a way to hide the sender's identity,
4493 but useful for sending a message again to the same recipients.
4497 Takes a list of messages and a user name
4498 and sends each message to the named user.
4500 and related header fields are prepended to the new copy of the message.
4518 .It Ic respondsender
4524 (ret) Without arguments the list of retained header fields is shown,
4525 otherwise the given list of header fields is added to the retain list:
4526 Header fields in the retain list are shown on the terminal when
4527 a message is displayed, all other header fields are suppressed.
4528 To display a message in its entirety, use the commands
4537 takes precedence over the mentioned.
4543 but saves the messages in a file named after the local part of the
4544 sender of the first message instead of (in
4546 and) taking a filename argument.
4550 (s) Takes a message list and a filename and appends each message in turn
4551 to the end of the file.
4552 If no filename is given, the
4555 The filename in quotes, followed by the generated character count
4556 is echoed on the user's terminal.
4557 If editing a primary system mailbox the messages are marked for deletion.
4558 Filename interpretation as described for the
4560 command is performed.
4577 Header fields thus marked are filtered out when saving a message by
4579 or when automatically saving to
4581 This command should only be applied to header fields that do not contain
4582 information needed to decode the message,
4583 as MIME content fields do.
4595 Header fields thus marked are the only ones saved with a message when
4598 or when automatically saving to
4603 The use of this command is strongly discouraged since it may strip
4604 header fields that are needed to decode the message correctly.
4608 Takes a message specification (list) and displays a header summary of
4609 all matching messages, as via
4611 This command is an alias of
4614 .Sx "Specifying messages" .
4618 Takes a message list and marks all messages as having been read.
4622 (se) Without arguments this command shows all internal variables which
4623 are currently known to \*(UA (they have been set).
4624 A more verbose listing will be produced if either of
4628 are set, in which case variables may be preceded with a comment line
4629 that gives some context of what \*(UA knows about the given variable.
4631 Otherwise the given variables (and arguments) are set or adjusted.
4632 Arguments are of the form
4634 (no space before or after
4638 if there is no value, i.e., a boolean variable.
4639 Quotation marks may be placed around any part of the assignment
4640 statement to quote blanks or tabs, e.g.,
4642 .Dl set indentprefix='->'
4644 If an argument begins with
4648 the effect is the same as invoking the
4650 command with the remaining part of the variable
4651 .Pf ( Ql unset save ) .
4655 that is known to map to an environment variable will automatically cause
4656 updates in the program environment (unsetting a variable in the
4657 environment requires corresponding system support).
4658 Please use the command
4660 for further environmental control.
4665 .Sx "INTERNAL VARIABLES"
4671 (sh) Invokes an interactive version of the shell.
4675 Without arguments the list of all currently defined shortcuts is
4677 Otherwise all given arguments (which need not be quoted except for
4678 whitespace) are treated as pairs of shortcuts and their expansions,
4679 creating new or changing already existing shortcuts, as necessary.
4680 Shortcuts may be removed via the command
4682 The expansion strings should be in the syntax that has been described
4691 but performs neither MIME decoding nor decryption, so that the raw
4692 message text is shown.
4696 (si) Shows the size in characters of each message of the given
4701 Shows the current sorting criterion when used without an argument.
4702 Otherwise creates a sorted representation of the current folder,
4705 command and the addressing modes such that they refer to messages in
4707 Message numbers are the same as in regular mode.
4711 a header summary in the new order is also displayed.
4712 Automatic folder sorting can be enabled by setting the
4714 variable, as in, e.g.,
4715 .Ql set autosort=thread .
4716 Possible sorting criterions are:
4718 .Bl -tag -compact -offset indent -width "subject"
4720 Sort the messages by their
4722 field, that is by the time they were sent.
4724 Sort messages by the value of their
4726 field, that is by the address of the sender.
4729 variable is set, the sender's real name (if any) is used.
4731 Sort the messages by their size.
4733 \*(OP Sort the message by their spam score, as has been classified by
4736 Sort the messages by their message status.
4738 Sort the messages by their subject.
4740 Create a threaded display.
4742 Sort messages by the value of their
4744 field, that is by the address of the recipient.
4747 variable is set, the recipient's real name (if any) is used.
4752 (so) The source command reads commands from the given file, which is
4753 subject to the usual filename expansions (see introductional words of
4755 If the given argument ends with a vertical bar
4757 then the argument will instead be interpreted as a shell command and
4758 \*(UA will read the output generated by it.
4759 Interpretation of commands read is stopped when an error is encountered.
4762 cannot be used from within macros that execute as
4763 .Va folder-hook Ns s
4766 i.e., it can only be called from macros that were
4773 (beside not supporting pipe syntax aka shell command input) is that
4774 this command will not generate an error if the given file argument
4775 cannot be opened successfully.
4779 \*(OP Takes a list of messages and clears their
4785 \*(OP Takes a list of messages and causes the
4787 to forget it has ever used them to train its Bayesian filter.
4788 Unless otherwise noted the
4790 flag of the message is inspected to chose whether a message shall be
4798 \*(OP Takes a list of messages and informs the Bayesian filter of the
4802 This also clears the
4804 flag of the messages in question.
4808 \*(OP Takes a list of messages and rates them using the configured
4809 .Va spam-interface ,
4810 without modifying the messages, but setting their
4812 flag as appropriate; because the spam rating headers are lost the rate
4813 will be forgotten once the mailbox is left.
4814 Refer to the manual section
4816 for the complete picture of spam handling in \*(UA.
4820 \*(OP Takes a list of messages and sets their
4826 \*(OP Takes a list of messages and informs the Bayesian filter of the
4832 flag of the messages in question.
4841 Create a threaded representation of the current folder,
4842 i.\|e. indent messages that are replies to other messages in the header
4843 display and change the
4845 command and the addressing modes such that they refer to messages in the
4847 Message numbers are the same as in unthreaded mode.
4851 a header summary in threaded order is also displayed.
4865 (to) Takes a message list and types out the first
4867 lines of each message on the users' terminal.
4868 The only header fields that are displayed are
4875 will instead honour configured lists).
4876 It is possible to apply compression to what is displayed by setting
4878 Messages are decrypted and converted to the terminal character set
4883 (tou) Takes a message list and marks the messages for saving in
4885 \*(UA deviates from the POSIX standard with this command,
4888 command will display the following message instead of the current one.
4894 but also displays out ignored header fields and all parts of MIME
4895 .Ql multipart/alternative
4900 (t) Takes a message list and types out each message on the users'
4906 For MIME multipart messages, all parts with a content type of
4910 are shown, the other are hidden except for their headers.
4911 Messages are decrypted and converted to the terminal character set
4916 Delete all given accounts.
4917 An error message is shown if a given account is not defined.
4920 will discard all existing accounts.
4924 (una) Takes a list of names defined by alias commands
4925 and discards the remembered groups of users.
4928 will discard all existing aliases.
4932 Takes a message list and marks each message as not having been answered.
4938 ing, specified by its context and input sequence, both of which may be
4939 specified as a wildcard (asterisk,
4943 will remove all bindings of all contexts.
4947 Only applicable to threaded mode.
4948 Takes a message list and makes the message and all replies to it visible
4949 in header summaries again.
4950 When a message becomes the current message,
4951 it is automatically made visible.
4952 Also when a message with collapsed replies is displayed,
4953 all of these are automatically uncollapsed.
4959 mapping for the given colour type (see
4961 for a list of types) and mapping; if the optional precondition argument
4962 is used then only the exact tuple of mapping and precondition is removed.
4965 will remove all mappings (no precondition allowed).
4967 .Sx "Coloured display"
4968 for the general picture.
4972 Deletes the custom headers given as arguments.
4975 will remove all custom headers.
4979 Undefine all given macros.
4980 An error message is shown if a given macro is not defined.
4983 will discard all existing macros.
4987 (u) Takes a message list and marks each message as not being deleted.
4991 Takes a message list and
4997 Takes a message list and marks each message as not being
5002 Removes the header field names from the list of ignored fields for the
5007 will remove all fields.
5011 Removes the header field names from the list of retained fields for the
5016 will remove all fields.
5020 Remove all the given command
5024 will remove all ghosts.
5028 Removes the header field names from the list of ignored fields.
5031 will remove all fields.
5035 Delete all given MIME types, e.g.,
5036 .Ql unmimetype text/plain
5037 will remove all registered specifications for the MIME type
5041 will discard all existing MIME types, just as will
5043 but which also reenables cache initialization via
5044 .Va mimetypes-load-control .
5048 Forget about all the given mailing lists.
5051 will remove all lists.
5056 .It Ic unmlsubscribe
5057 Remove the subscription attribute from all given mailing lists.
5060 will clear the attribute from all lists which have it set.
5071 Takes a message list and marks each message as not having been read.
5075 Removes the header field names from the list of retained fields.
5078 will remove all fields.
5082 Removes the header field names from the list of ignored fields for
5086 will remove all fields.
5090 Removes the header field names from the list of retained fields for
5094 will remove all fields.
5098 (uns) Takes a list of internal variable names and discards their
5099 remembered values; the reverse of
5106 Deletes the shortcut names given as arguments.
5109 will remove all shortcuts.
5113 Disable sorted or threaded mode
5119 return to normal message order and,
5123 displays a header summary.
5133 Perform URL percent codec operations, rather according to RFC 3986,
5134 on all given strings.
5135 This is character set agnostic and thus locale dependent, and it may
5136 decode bytes which are invalid in the current locale, unless the input
5137 solely consists of characters in the portable character set, see
5138 .Sx "Character sets" .
5139 The first argument specifies the operation:
5143 perform plain URL percent en- and decoding, respectively.
5147 perform a slightly modified operation which should be better for
5148 pathnames: it doesn't allow a tilde
5150 and will neither accept hyphen
5154 as an initial character.
5158 Edit the values of or create the given variable(s) in the
5160 Boolean variables cannot be edited.
5164 This command produces the same output as the listing mode of
5168 ity adjustments, but only for the given variables.
5172 \*(OP Takes a message list and verifies each message.
5173 If a message is not a S/MIME signed message,
5174 verification will fail for it.
5175 The verification process checks if the message was signed using a valid
5177 if the message sender's email address matches one of those contained
5178 within the certificate,
5179 and if the message content has been altered.
5191 (v) Takes a message list and invokes the display editor on each message.
5192 Modified contents are discarded unless the
5198 (w) For conventional messages the body without all headers is written.
5199 The original message is never marked for deletion in the originating
5201 The output is decrypted and converted to its native format as necessary.
5202 If the output file exists, the text is appended.
5203 If a message is in MIME multipart format its first part is written to
5204 the specified file as for conventional messages, handling of the remains
5205 depends on the execution mode.
5206 No special handling of compressed files is performed.
5208 In interactive mode the user is consecutively asked for the filenames of
5209 the processed parts.
5210 For convience saving of each part may be skipped by giving an empty
5211 value, the same result as writing it to
5213 Shell piping the part content by specifying a leading vertical bar
5215 character for the filename is supported.
5216 Other user input is expanded as usually for folders, e.g., tilde
5217 expansion is performed, and contents of the destination file are
5218 overwritten if the file previously existed.
5220 \*(ID In non-interactive mode any part which does not specify a filename
5221 is ignored, and suspicious parts of filenames of the remaining parts are
5222 URL percent encoded (as via
5224 to prevent injection of malicious character sequences, resulting in
5225 a filename that will be written into the current directory.
5226 Existing files won't be overwritten, instead the part number or
5227 a dot are appended after a number sign
5229 to the name until file creation succeeds (or fails due to other
5239 \*(UA presents message headers in
5241 fuls as described under the
5244 Without arguments this command scrolls to the next window of messages,
5245 likewise if the argument is
5249 scrolls to the last,
5251 scrolls to the first, and
5256 A number argument prefixed by
5260 indicates that the window is calculated in relation to the current
5261 position, and a number without a prefix specifies an absolute position.
5267 but scrolls to the next or previous window that contains at least one
5276 .\" .Sh TILDE ESCAPES {{{
5279 Here is a summary of the tilde escapes,
5280 which are used to perform special functions when composing messages.
5281 Tilde escapes are only recognized at the beginning of lines.
5284 is somewhat of a misnomer since the actual escape character can be
5285 changed by adjusting the option
5288 .Bl -tag -width ".Ic __ filename"
5291 Insert the string of text in the message prefaced by a single
5293 (If the escape character has been changed,
5294 that character must be doubled
5295 in order to send it at the beginning of a line.)
5298 .It Ic ~! Ar command
5299 Execute the indicated shell
5301 then return to the message.
5305 Same effect as typing the end-of-file character.
5308 .It Ic ~: Ar \*(UA-command Ns \0or Ic ~_ Ar \*(UA-command
5309 Execute the given \*(UA command.
5310 Not all commands, however, are allowed.
5314 Write a summary of command escapes.
5317 .It Ic ~< Ar filename
5322 .It Ic ~<! Ar command
5324 is executed using the shell.
5325 Its standard output is inserted into the message.
5328 .It Ic ~@ Op Ar filename...
5329 With no arguments, edit the attachment list interactively.
5330 If an attachment's file name is left empty,
5331 that attachment is deleted from the list.
5332 When the end of the attachment list is reached,
5333 \*(UA will ask for further attachments until an empty name is given.
5334 If a given file name solely consists of the number sign
5336 followed by a valid message number of the currently active mailbox, then
5337 the given message is attached as a MIME
5339 and the rest of this section does not apply.
5341 If character set conversion has been compiled into \*(UA, then this mode
5342 gives the user the option to specify input and output character sets,
5343 unless the file extension indicates binary content, in which case \*(UA
5344 asks whether this step shall be skipped for the attachment in question.
5345 If not skipped, then the charset that succeeds to represent the
5346 attachment data will be used in the
5348 MIME parameter of the mail message:
5350 .Bl -bullet -compact
5352 If input and output character sets are specified, then the conversion is
5353 performed on the fly.
5354 The user will be asked repeatedly until the desired conversion succeeds.
5356 If only an output character set is specified, then the input is assumed
5359 charset and will be converted to the given output charset on the fly.
5360 The user will be asked repeatedly until the desired conversion succeeds.
5362 If no character sets are specified at all then the algorithm that is
5363 documented in the section
5364 .Sx "Character sets"
5365 is applied, but directly and on the fly.
5366 The user will be asked repeatedly until the desired conversion succeeds.
5368 Finally, if an input-, but no output character set is specified, then no
5369 conversion is ever performed, but the
5371 MIME parameter value will still be set to the user input.
5373 The character set selection loop can be left by typing
5375 i.e., causing an interrupt.
5376 .\" \*(OU next sentence
5377 Note that before \*(UA version 15.0 this terminates the entire
5378 current attachment selection, not only the character set selection.
5381 Without character set conversion support, \*(UA will ask for the input
5382 character set only, and it'll set the
5384 MIME parameter value to the given input, if any;
5385 if no user input is seen then the
5387 character set will be used for the parameter value instead.
5388 Note that the file extension check isn't performed in this mode, since
5389 no conversion will take place anyway.
5391 Note that in non-interactive mode, for reproduceabilities sake, there
5392 will always be two questions for each attachment, regardless of whether
5393 character set conversion is available and what the file extension is.
5394 The first asks for the filename, and the second asks for the input
5395 character set to be passed through to the corresponding MIME parameter;
5396 no conversion will be tried if there is input to the latter question,
5397 otherwise the usual conversion algorithm, as above, is applied.
5398 For message attachments, the answer to the second question is completely
5403 arguments are specified for the
5405 command they are treated as a file list of
5407 -style quoted arguments, optionally also separated by commas, which are
5408 expanded and then appended to the existing list of message attachments.
5409 Message attachments can only be added via the first method.
5410 In this mode the (text) attachments are assumed to be in
5412 encoding, and will be evaluated as documented in the section
5413 .Sx "Character sets" .
5417 Inserts the string contained in the
5420 .Ql Ic ~i Ns \0Sign ) .
5421 The escape sequences tabulator
5429 Inserts the string contained in the
5432 .Ql Ic ~i Ns \0sign ) .
5433 The escape sequences tabulator
5440 .It Ic ~b Ar name ...
5441 Add the given names to the list of blind carbon copy recipients.
5444 .It Ic ~c Ar name ...
5445 Add the given names to the list of carbon copy recipients.
5449 Read the file specified by the
5451 variable into the message.
5455 Invoke the text editor on the message collected so far.
5456 After the editing session is finished,
5457 the user may continue appending text to the message.
5460 .It Ic ~F Ar messages
5461 Read the named messages into the message being sent, including all
5462 message headers and MIME parts.
5463 If no messages are specified, read in the current message.
5466 .It Ic ~f Ar messages
5467 Read the named messages into the message being sent.
5468 If no messages are specified, read in the current message.
5472 lists are used to modify the message headers.
5473 For MIME multipart messages,
5474 only the first displayable part is included.
5478 Edit the message header fields
5483 by typing each one in turn and allowing the user to edit the field.
5484 The default values for these fields originate from the
5492 Edit the message header fields
5498 by typing each one in turn and allowing the user to edit the field.
5501 .It Ic ~i Ar variable
5502 Insert the value of the specified variable into the message,
5503 adding a newline character at the end.
5504 The message remains unaltered if the variable is unset or empty.
5505 The escape sequences tabulator
5512 .It Ic ~M Ar messages
5513 Read the named messages into the message being sent,
5516 If no messages are specified, read the current message.
5519 .It Ic ~m Ar messages
5520 Read the named messages into the message being sent,
5523 If no messages are specified, read the current message.
5527 lists are used to modify the message headers.
5528 For MIME multipart messages,
5529 only the first displayable part is included.
5533 Display the message collected so far,
5534 prefaced by the message header fields
5535 and followed by the attachment list, if any.
5539 Abort the message being sent,
5540 copying it to the file specified by the
5547 .It Ic ~R Ar filename
5548 Read the named file into the message, indented by
5552 .It Ic ~r Ar filename
5553 Read the named file into the message.
5557 Cause the named string to become the current subject field.
5560 .It Ic ~t Ar name ...
5561 Add the given name(s) to the direct recipient list.
5564 .It Ic ~U Ar messages
5565 Read in the given / current message(s) excluding all headers, indented by
5569 .It Ic ~u Ar messages
5570 Read in the given / current message(s), excluding all headers.
5574 Invoke an alternate editor (defined by the
5576 option) on the message collected so far.
5577 Usually, the alternate editor will be a screen editor.
5578 After the editor is quit,
5579 the user may resume appending text to the end of the message.
5582 .It Ic ~w Ar filename
5583 Write the message onto the named file.
5585 the message is appended to it.
5591 except that the message is not saved at all.
5594 .It Ic ~| Ar command
5595 Pipe the message through the specified filter command.
5596 If the command gives no output or terminates abnormally,
5597 retain the original text of the message.
5600 is often used as a rejustifying filter.
5605 .\" .Sh INTERNAL VARIABLES {{{
5606 .Sh "INTERNAL VARIABLES"
5608 Internal \*(UA variables are controlled via the
5612 commands; prefixing a variable name with the string
5616 has the same effect as using
5622 Creation or editing of variables can be performed in the
5627 will give more insight on the given variable(s), and
5629 when called without arguments, will show a listing of all variables.
5630 Both commands support a more
5633 Some well-known variables will also become inherited from the
5636 implicitly, others can be explicitly imported with the command
5638 and henceforth share the said properties.
5641 Two different kind of internal variables exist.
5642 There are boolean variables, which can only be in one of the two states
5646 and value variables with a(n optional) string value.
5647 For the latter proper quoting is necessary upon assignment time, the
5648 introduction of the section
5650 documents the supported quoting rules.
5652 .Bd -literal -offset indent
5653 wysh set one=val\e 1 two="val 2" \e
5654 three='val "3"' four=$'val \e'4\e''
5655 varshow one two three four
5656 unset one two three four
5660 Dependent upon the actual option the string values will be interpreted
5661 as numbers, colour names, normal text etc., but there also exists
5662 a special kind of string value, the
5663 .Dq boolean string ,
5664 which must either be a decimal integer (in which case
5668 and any other value is true) or any of the (case-insensitive) strings
5674 for a false boolean and
5680 for a true boolean; a special kind of boolean string is the
5682 which is a boolean string that can optionally be prefixed with the
5683 (case-insensitive) term
5687 which causes prompting of the user in interactive mode, with the given
5688 boolean as the default value.
5690 .\" .Ss "Initial settings" {{{
5691 .\" (Keep in SYNC: ./nail.h:okeys, ./nail.rc, ./nail.1:"Initial settings")
5692 .Ss "Initial Settings"
5694 The standard POSIX 2008/Cor 2-2016 mandates the following initial
5700 .Pf no Va autoprint ,
5714 .Pf no Va ignoreeof ,
5716 .Pf no Va keepsave ,
5718 .Pf no Va outfolder ,
5723 (note that \*(UA deviates from the standard by using
5727 special prompt escape results in
5735 .Pf no Va sendwait ,
5744 Notes: \*(UA doesn't support the
5746 variable \(en use command line options or
5748 to pass options through to a
5750 And the default global
5752 file (which is loaded unless the
5754 command line flag has been used or the
5755 .Ev NAIL_NO_SYSTEM_RC
5756 environment variable is set) bends those initial settings a bit, e.g.,
5757 it sets the variables
5762 to name a few, calls
5764 etc., and should thus be taken into account.
5767 .\" .Ss "Variables" {{{
5770 .Bl -tag -width ".It Va _utoprin_"
5772 .It Va add-file-recipients
5773 \*(BO When file or pipe recipients have been specified,
5774 mention them in the corresponding address fields of the message instead
5775 of silently stripping them from their recipient list.
5776 By default such addressees are not mentioned.
5780 \*(BO Causes only the local part to be evaluated
5781 when comparing addresses.
5785 \*(BO Causes messages saved in
5787 to be appended to the end rather than prepended.
5788 This should always be set.
5792 \*(BO Causes \*(UA to prompt for the subject of each message sent.
5793 If the user responds with simply a newline,
5794 no subject field will be sent.
5798 \*(BO Causes the prompts for
5802 lists to appear after the message has been edited.
5806 \*(BO If set, \*(UA asks for files to attach at the end of each message,
5807 shall the list be found empty at that time.
5808 An empty line finalizes the list.
5812 \*(BO Causes the user to be prompted for carbon copy recipients
5813 (at the end of each message if
5817 are set) shall the list be found empty (at that time).
5818 An empty line finalizes the list.
5822 \*(BO Causes the user to be prompted for blind carbon copy
5823 recipients (at the end of each message if
5827 are set) shall the list be found empty (at that time).
5828 An empty line finalizes the list.
5832 \*(BO\*(OP Causes the user to be prompted if the message is to be
5833 signed at the end of each message.
5836 variable is ignored when this variable is set.
5840 \*(BO Alternative name for
5847 .It Va attachment-ask-content-description , \
5848 attachment-ask-content-disposition , \
5849 attachment-ask-content-id , \
5850 attachment-ask-content-type
5851 \*(BO If set then the user will be prompted for some attachment
5852 information when editing the attachment list.
5853 It is advisable to not use these but for the first of the variables;
5854 even for that it has to be noted that the data is used
5860 A sequence of characters to display in the
5864 as shown in the display of
5866 each for one type of messages (see
5867 .Sx "Message states" ) ,
5868 with the default being
5871 .Ql NU\ \ *HMFAT+\-$~
5874 variable is set, in the following order:
5876 .Bl -tag -compact -offset indent -width ".It Ql _"
5898 start of a collapsed thread.
5900 an uncollapsed thread (TODO ignored for now).
5904 classified as possible spam.
5910 Specifies a list of recipients to which a blind carbon copy of each
5911 outgoing message will be sent automatically.
5915 Specifies a list of recipients to which a carbon copy of each outgoing
5916 message will be sent automatically.
5920 \*(BO Causes threads to be collapsed automatically when threaded mode
5927 \*(BO Causes the delete command to behave like
5929 thus, after deleting a message the next one will be typed automatically.
5933 \*(BO\*(OB Causes threaded mode (see the
5935 command) to be entered automatically when a folder is opened.
5937 .Ql autosort=thread .
5941 Causes sorted mode (see the
5943 command) to be entered automatically with the value of this option as
5944 sorting method when a folder is opened, e.g.,
5945 .Ql set autosort=thread .
5949 \*(BO Enables the substitution of
5951 by the contents of the last command line in shell escapes.
5954 .It Va batch-exit-on-error
5955 \*(BO If the batch mode has been enabled via the
5957 command line option, then this variable will be consulted whenever \*(UA
5958 completes one operation (returns to the command prompt); if it is set
5959 then \*(UA will terminate if the last operation generated an error.
5963 \*(OP Terminals generate multi-byte sequences for certain forms of
5964 input, for example for function and other special keys.
5965 Some terminals however do not write these multi-byte sequences as
5966 a whole, but byte-by-byte, and the latter is what \*(UA actually reads.
5967 This variable specifies the timeout in milliseconds that the MLE (see
5968 .Sx "On terminal control and line editor" )
5969 waits for more bytes to arrive unless it considers a sequence
5975 \*(BO Causes automatic display of a header summary after executing a
5977 command, and thus complements the standard variable
5979 which controls header summary display on program startup.
5980 It is only meaningful if
5986 \*(BO Sets some cosmetical features to traditional BSD style;
5987 has the same affect as setting
5989 and all other variables prefixed with
5991 it also changes the meaning of the \*(UA specific
5994 escape sequence and changes behaviour of
5996 (which doesn't exist in BSD).
6000 \*(BO Changes the letters shown in the first column of a header
6001 summary to traditional BSD style.
6005 \*(BO Changes the display of columns in a header summary to traditional
6010 \*(BO Changes some informational messages to traditional BSD style.
6016 field to appear immediately after the
6018 field in message headers and with the
6020 .Sx "TILDE ESCAPES" .
6024 The value that should appear in the
6028 MIME header fields when no character set conversion of the message data
6030 This defaults to US-ASCII, and the chosen character set should be
6031 US-ASCII compatible.
6035 \*(OP The default 8-bit character set that is used as an implicit last
6036 member of the variable
6038 This defaults to UTF-8.
6039 If no character set conversion capabilities are available in \*(UA then
6040 the only supported character set is
6042 Refer to the section
6043 .Sx "Character sets"
6044 for the complete picture of character set conversion in \*(UA.
6047 .It Va charset-unknown-8bit
6048 \*(OP RFC 1428 specifies conditions when internet mail gateways shall
6050 the content of a mail message by using a character set with the name
6052 Because of the unclassified nature of this character set \*(UA will not
6053 be capable to convert this character set to any other character set.
6054 If this variable is set any message part which uses the character set
6056 is assumed to really be in the character set given in the value,
6057 otherwise the (final) value of
6059 is used for this purpose.
6061 This variable will also be taken into account if a MIME type (see
6062 .Sx "The mime.types files" )
6063 of a MIME message part that uses the
6065 character set is forcefully treated as text.
6069 The default value for the
6074 .It Va colour-disable
6075 \*(BO\*(OP Forcefully disable usage of colours.
6076 Also see the section
6077 .Sx "Coloured display" .
6081 \*(BO\*(OP Whether colour shall be used for output that is paged through
6083 Note that pagers may need special flags, e.g.,
6091 in order to support colours.
6092 Often doing manual adjustments is unnecessary since \*(UA may perform
6093 adjustments dependend on the value of the environment variable
6095 (see there for more).
6099 In a(n interactive) terminal session, then if this valued option is set
6100 it'll be used as a threshold to determine how many lines the given
6101 output has to span before it will be displayed via the configured
6105 can be forced by setting this to the value
6107 setting it without a value will deduce the current height of the
6108 terminal screen to compute the treshold (see
6116 \*(OB A variable counterpart of the
6118 command (see there for documentation), interpreted as a comma-separated
6119 list of custom headers to be injected, to include commas in the header
6120 bodies escape them with reverse solidus, e.g.:
6122 .Dl set customhdr='Hdr1: Body1-1\e, Body1-2, Hdr2: Body2'
6128 the message date, if any is to be displayed according to the format of
6130 is by default taken from the
6132 line of the message.
6133 If this variable is set the date as given in the
6135 header field is used instead, converted to local time.
6136 To control the display format of the date assign a valid
6141 format should not be used, because \*(UA doesn't take embedded newlines
6142 into account when calculating how many lines fit onto the screen.)
6144 .Va datefield-markout-older .
6147 .It Va datefield-markout-older
6148 This option, when set in addition to
6152 messages (concept is rather comparable to the
6154 option of the POSIX utility
6156 The content interpretation is identical to
6161 \*(BO Enables debug messages and obsoletion warnings, disables the
6162 actual delivery of messages and also implies
6168 .It Va disposition-notification-send
6170 .Ql Disposition-Notification-To:
6171 header (RFC 3798) with the message.
6175 .\" TODO .It Va disposition-notification-send-HOST
6177 .\".Va disposition-notification-send
6178 .\" for SMTP accounts on a specific host.
6179 .\" TODO .It Va disposition-notification-send-USER@HOST
6181 .\".Va disposition-notification-send
6182 .\"for a specific account.
6186 \*(BO When dot is set, a period
6188 on a line by itself during message input in (interactive) compose mode
6189 will be treated as end-of-message (in addition to the normal end-of-file
6198 .It Va dotlock-ignore-error
6199 \*(BO\*(OP Synchronization of mailboxes which \*(UA treats as system
6200 mailboxes (see the command
6202 will be protected with so-called dotlock files\(emthe traditional mail
6203 spool file locking method\(emin addition to system file locking.
6204 Because \*(UA ships with a privilege-separated dotlock creation program
6205 that should always be able to create such a dotlock file there is no
6206 good reason to ignore dotlock file creation errors, and thus these are
6207 fatal unless this variable is set.
6211 \*(BO If this variable is set then the editor is started automatically
6212 when a message is composed in interactive mode, as if the
6218 variable is implied for this automatically spawned editor session.
6222 \*(BO When a message is edited while being composed,
6223 its header is included in the editable text.
6233 fields are accepted within the header, other fields are ignored.
6237 \*(BO When entering interactive mode \*(UA normally writes
6238 .Dq \&No mail for user
6239 and exits immediately if a mailbox is empty or doesn't exist.
6240 If this option is set \*(UA starts even with an empty or nonexistent
6241 mailbox (the latter behaviour furtherly depends upon
6247 Suggestion for the MIME encoding to use in outgoing text messages
6249 Valid values are the default
6250 .Ql quoted-printable ,
6255 may cause problems when transferring mail messages over channels that
6256 are not ESMTP (RFC 1869) compliant.
6257 If there is no need to encode a message,
6259 transfer mode is always used regardless of this variable.
6260 Binary data is always encoded as
6265 If defined, the first character of this option
6266 gives the character to use in place of
6269 .Sx "TILDE ESCAPES" .
6273 If not set then file and command pipeline targets are not allowed,
6274 and any such address will be filtered out, giving a warning message.
6275 If set without a value then all possible recipient address
6276 specifications will be accepted \(en see the section
6277 .Sx "On sending mail, and non-interactive mode"
6279 To accept them, but only in interactive mode, or when tilde commands
6280 were enabled explicitly by using one of the command line options
6284 set this to the (case-insensitive) value
6286 (note right now this is actually like setting
6287 .Ql restrict,-all,+name,+addr ) .
6289 In fact the value is interpreted as a comma-separated list of values.
6292 then the existence of disallowed specifications is treated as a hard
6293 send error instead of only filtering them out.
6294 The remaining values specify whether a specific type of recipient
6295 address specification is allowed (optionally indicated by a plus sign
6297 prefix) or disallowed (prefixed with a hyphen
6301 addresses all possible address specifications,
6305 command pipeline targets,
6307 plain user names and (MTA) aliases (\*(OB
6309 may be used as an alternative syntax to
6314 These kind of values are interpreted in the given order, so that
6315 .Ql restrict,\:fail,\:+file,\:-all,\:+addr
6316 will cause hard errors for any non-network address recipient address
6317 unless \*(UA is in interactive mode or has been started with the
6321 command line option; in the latter case(s) any address may be used, then.
6325 Unless this variable is set additional
6327 (Mail-Transfer-Agent)
6328 arguments from the command line, as can be given after a
6330 separator, are ignored due to safety reasons.
6331 However, if set to the special (case-insensitive) value
6333 then the presence of additional MTA arguments is treated as a hard
6334 error that causes \*(UA to exit with failure status.
6335 A lesser strict variant is the otherwise identical
6337 which does accept such arguments in interactive mode, or if tilde
6338 commands were enabled explicitly by using one of the command line options
6345 \*(RO String giving a list of features \*(UA, preceded with a plus-sign
6347 if the feature is available, and a minus-sign
6350 The output of the command
6352 will include this information.
6356 \*(BO This option reverses the meanings of a set of reply commands,
6357 turning the lowercase variants, which by default address all recipients
6358 included in the header of a message
6359 .Pf ( Ic reply , respond , followup )
6360 into the uppercase variants, which by default address the sender only
6361 .Pf ( Ic Reply , Respond , Followup )
6364 .Ic replysender , respondsender , followupsender
6366 .Ic replyall , respondall , followupall
6367 are not affected by the current setting of
6372 .It Va file-hook-load-EXTENSION , file-hook-save-EXTENSION
6373 It is possible to install file hooks which will be used by the
6375 command in order to be able to transparently handle (through an
6376 intermediate temporary file) files with specific
6378 s: the variable values can include shell snippets and are expected to
6379 write data to standard output / read data from standard input,
6381 \*(ID The variables may not be changed while there is a mailbox
6383 .Bd -literal -offset indent
6384 set file-hook-load-xy='echo >&2 XY-LOAD; gzip -cd' \e
6385 file-hook-save-xy='echo >&2 XY-SAVE; gzip -c' \e
6386 record=+null-sent.xy
6391 The default path under which mailboxes are to be saved:
6392 file names that begin with the plus-sign
6394 will be expanded by prefixing them with the value of this variable.
6395 The same special syntax conventions as documented for the
6397 command may be used; if the non-empty value doesn't start with a solidus
6401 will be prefixed automatically.
6402 If unset or the empty string any
6404 prefixing file names will remain unexpanded.
6408 This variable can be set to the name of a
6410 macro which will be called whenever a
6413 The macro will also be invoked when new mail arrives,
6414 but message lists for commands executed from the macro
6415 only include newly arrived messages then.
6417 are activated by default in a folder hook, causing the covered settings
6418 to be reverted once the folder is left again.
6421 Macro behaviour, including option localization, will change in v15.
6422 Please be aware of that and possibly embed a version check in a resource
6426 .It Va folder-hook-FOLDER
6431 Unlike other folder specifications, the fully expanded name of a folder,
6432 without metacharacters, is used to avoid ambiguities.
6433 However, if the mailbox resides under
6437 specification is tried in addition, e.g., if
6441 (and thus relative to the user's home directory) then
6442 .Pa /home/usr1/mail/sent
6444 .Ql folder-hook-/home/usr1/mail/sent
6445 first, but then followed by
6446 .Ql folder-hook-+sent .
6450 \*(BO Controls whether a
6451 .Ql Mail-Followup-To:
6452 header is generated when sending messages to known mailing lists.
6454 .Va followup-to-honour
6456 .Ic mlist , mlsubscribe , reply
6461 .It Va followup-to-honour
6463 .Ql Mail-Followup-To:
6464 header is honoured when group-replying to a message via
6468 This is a quadoption; if set without a value it defaults to
6478 .It Va forward-as-attachment
6479 \*(BO Original messages are normally sent as inline text with the
6482 and only the first part of a multipart message is included.
6483 With this option messages are sent as unmodified MIME
6485 attachments with all of their parts included.
6489 The address (or a list of addresses) to put into the
6491 field of the message header, quoting RFC 5322:
6492 the author(s) of the message, that is, the mailbox(es) of the person(s)
6493 or system(s) responsible for the writing of the message.
6496 ing to messages these addresses are handled as if they were in the
6500 If the machine's hostname is not valid at the Internet (for example at
6501 a dialup machine) then either this variable or
6503 (\*(IN and with a defined SMTP protocol in
6506 adds even more fine-tuning capabilities),
6510 contains more than one address,
6513 variable is required (according to the standard RFC 5322).
6517 \*(BO When replying to or forwarding a message \*(UA normally removes
6518 the comment and name parts of email addresses.
6519 If this variable is set such stripping is not performed,
6520 and comments, names etc. are retained.
6524 The string to put before the text of a message with the
6528 .Va forward-as-attachment
6531 .Dq -------- Original Message --------
6532 if unset; No heading is put if it is set to the empty string.
6536 \*(BO Causes the header summary to be written at startup and after
6537 commands that affect the number of messages or the order of messages in
6538 the current folder; enabled by default.
6539 The command line option
6545 complements this and controls header summary display on folder changes.
6550 A format string to use for the summary of
6552 similar to the ones used for
6555 Format specifiers in the given string start with a percent character
6557 and may be followed by an optional decimal number indicating the field
6558 width \(em if that is negative, the field is to be left-aligned.
6559 Valid format specifiers are:
6562 .Bl -tag -compact -offset indent -width "_%%_"
6564 A plain percent character.
6567 a space character but for the current message
6569 for which it expands to
6573 a space character but for the current message
6575 for which it expands to
6578 \*(OP The spam score of the message, as has been classified via the
6581 Shows only a replacement character if there is no spam support.
6583 Message attribute character (status flag); the actual content can be
6587 The date when the message was received, or the date found in the
6591 variable is set (optionally to a date display format string).
6593 The indenting level in threaded mode.
6595 The address of the message sender.
6597 The message thread tree structure.
6598 (Note that this format doesn't support a field width.)
6600 The number of lines of the message, if available.
6604 The number of octets (bytes) in the message, if available.
6606 Message subject (if any).
6608 Message subject (if any) in double quotes.
6610 Message recipient flags: is the addressee of the message a known or
6611 subscribed mailing list \(en see
6616 The position in threaded/sorted order.
6620 .Ql %>\&%a\&%m\ %-18f\ %16d\ %4l/%\-5o\ %i%-s ,
6622 .Ql %>\&%a\&%m\ %20-f\ \ %16d\ %3l/%\-5o\ %i%-S
6633 .It Va headline-bidi
6634 Bidirectional text requires special treatment when displaying headers,
6635 because numbers (in dates or for file sizes etc.) will not affect the
6636 current text direction, in effect resulting in ugly line layouts when
6637 arabic or other right-to-left text is to be displayed.
6638 On the other hand only a minority of terminals is capable to correctly
6639 handle direction changes, so that user interaction is necessary for
6641 Note that extended host system support is required nonetheless, e.g.,
6642 detection of the terminal character set is one precondition;
6643 and this feature only works in an Unicode (i.e., UTF-8) locale.
6645 In general setting this variable will cause \*(UA to encapsulate text
6646 fields that may occur when displaying
6648 (and some other fields, like dynamic expansions in
6650 with special Unicode control sequences;
6651 it is possible to fine-tune the terminal support level by assigning
6653 no value (or any value other than
6658 will make \*(UA assume that the terminal is capable to properly deal
6659 with Unicode version 6.3, in which case text is embedded in a pair of
6660 U+2068 (FIRST STRONG ISOLATE) and U+2069 (POP DIRECTIONAL ISOLATE)
6662 In addition no space on the line is reserved for these characters.
6664 Weaker support is chosen by using the value
6666 (Unicode 6.3, but reserve the room of two spaces for writing the control
6667 sequences onto the line).
6672 select Unicode 1.1 support (U+200E, LEFT-TO-RIGHT MARK); the latter
6673 again reserves room for two spaces in addition.
6677 \*(OP If a line editor is available then this can be set to
6678 name the (expandable) path of the location of a permanent history file.
6681 .It Va history-gabby
6682 \*(BO\*(OP Add more entries to the history as is normally done.
6685 .It Va history-gabby-persist
6686 \*(BO\*(OP \*(UA's own MLE will not save the additional
6688 entries in persistent storage unless this variable is set.
6689 On the other hand it will not loose the knowledge of whether
6690 a persistent entry was gabby or not.
6696 \*(OP If a line editor is available this value restricts the
6697 amount of history entries that are saved into a set and valid
6699 A value of less than 0 disables this feature;
6700 note that loading and incorporation of
6702 upon program startup can also be suppressed by doing this.
6703 If unset or 0, a default value will be used.
6704 Dependent on the available line editor this will also define the
6705 number of history entries in memory;
6706 it is also editor-specific whether runtime updates of this value will
6711 \*(BO This option is used to hold messages in the system
6713 and it is set by default.
6717 Use this string as hostname when expanding local addresses instead of
6718 the value obtained from
6727 Note that when SMTP transport is not used (via
6729 then it is normally the responsibility of the MTA to create these
6730 fields, \*(IN in conjunction with SMTP however
6732 also influences the results:
6733 you should produce some test messages with the desired combination of
6742 \*(BO\*(OP Can be used to turn off the automatic conversion of domain
6743 names according to the rules of IDNA (internationalized domain names
6745 Since the IDNA code assumes that domain names are specified with the
6747 character set, an UTF-8 locale charset is required to represent all
6748 possible international domain names (before conversion, that is).
6752 \*(BO Ignore interrupt signals from the terminal while entering
6753 messages; instead echo them as
6755 characters and discard the current line.
6759 \*(BO Ignore end-of-file conditions
6760 .Pf ( Ql control-D )
6761 in compose mode on message input and in interactive command input.
6762 If set an interactive command input session can only be left by
6763 explicitly using one of the commands
6767 and message input in compose mode can only be terminated by entering
6770 on a line by itself or by using the
6772 .Sx "TILDE ESCAPES" ;
6774 overrides a setting of
6779 If this is set to a non-empty string it will be used for expansions of
6784 The value supports a subset of filename expansions itself.
6795 option for indenting messages,
6796 in place of the normal tabulator character
6798 which is the default.
6799 Be sure to quote the value if it contains spaces or tabs.
6803 \*(BO If set, an empty mailbox file is not removed.
6804 This may improve the interoperability with other mail user agents
6805 when using a common folder directory, and prevents malicious users
6806 from creating fake mailboxes in a world-writable spool directory.
6807 Note this only applies to local regular (MBOX) files, other mailbox
6808 types will never be removed.
6811 .It Va keep-content-length
6812 \*(BO When (editing messages and) writing
6814 mailbox files \*(UA can be told to keep the
6818 header fields that some MUAs generate by setting this variable.
6819 Since \*(UA does neither use nor update these non-standardized header
6820 fields (which in itself shows one of their conceptual problems),
6821 stripping them should increase interoperability in between MUAs that
6822 work with with same mailbox files.
6823 Note that, if this is not set but
6824 .Va writebackedited ,
6825 as below, is, a possibly performed automatic stripping of these header
6826 fields already marks the message as being modified.
6830 \*(BO When a message is saved it is usually discarded from the
6831 originating folder when \*(UA is quit.
6832 Setting this option causes all saved message to be retained.
6835 .It Va line-editor-disable
6836 \*(BO Turn off any enhanced line editing capabilities (see
6837 .Sx "On terminal control and line editor"
6841 .It Va line-editor-no-defaults
6842 \*(BO\*(OP Do not establish any default key binding.
6846 \*(BO When a message is replied to and this variable is set,
6847 it is marked as having been answered.
6848 This mark has no technical meaning in the mail system;
6849 it just causes messages to be marked in the header summary,
6850 and makes them specially addressable.
6854 \*(BO Internal development variable.
6857 .It Va message-id-disable
6858 \*(BO By setting this option the generation of
6860 can be completely suppressed, effectively leaving this task up to the
6862 (Mail-Transfer-Agent) or the SMTP server.
6863 (According to RFC 5321 your SMTP server is not required to add this
6864 field by itself, so you should ensure that it accepts messages without a
6868 .It Va message-inject-head
6869 A string to put at the beginning of each new message.
6870 The escape sequences tabulator
6877 .It Va message-inject-tail
6878 A string to put at the end of each new message.
6879 The escape sequences tabulator
6887 \*(BO Usually, when an
6889 expansion contains the sender, the sender is removed from the expansion.
6890 Setting this option suppresses these removals.
6895 option to be passed through to the
6897 (Mail-Transfer-Agent); though most of the modern MTAs no longer document
6898 this flag, no MTA is known which doesn't support it (for historical
6902 .It Va mime-allow-text-controls
6903 \*(BO When sending messages, each part of the message is MIME-inspected
6904 in order to classify the
6907 .Ql Content-Transfer-Encoding:
6910 that is required to send this part over mail transport, i.e.,
6911 a computation rather similar to what the
6913 command produces when used with the
6917 This classification however treats text files which are encoded in
6918 UTF-16 (seen for HTML files) and similar character sets as binary
6919 octet-streams, forcefully changing any
6924 .Ql application/octet-stream :
6925 If that actually happens a yet unset charset MIME parameter is set to
6927 effectively making it impossible for the receiving MUA to automatically
6928 interpret the contents of the part.
6930 If this option is set, and the data was unambiguously identified as text
6931 data at first glance (by a
6935 file extension), then the original
6937 will not be overwritten.
6940 .It Va mime-alternative-favour-rich
6941 \*(BO If this variable is set then rich MIME alternative parts (e.g.,
6942 HTML) will be preferred in favour of included plain text versions when
6943 displaying messages, provided that a handler exists which produces
6944 output that can be (re)integrated into \*(UA's normal visual display.
6945 (E.g., at the time of this writing some newsletters ship their full
6946 content only in the rich HTML part, whereas the plain text part only
6947 contains topic subjects.)
6950 .It Va mime-counter-evidence
6953 field is used to decide how to handle MIME parts.
6954 Some MUAs however don't use
6956 or a similar mechanism to correctly classify content, but simply specify
6957 .Ql application/octet-stream ,
6958 even for plain text attachments like
6960 If this variable is set then \*(UA will try to classify such MIME
6961 message parts on its own, if possible, for example via a possibly
6962 existing attachment filename.
6963 A non-empty value may also be given, in which case a number is expected,
6964 actually a carrier of bits.
6965 Creating the bit-carrying number is a simple addition:
6966 .Bd -literal -offset indent
6967 ? !echo Value should be set to $((2 + 4 + 8))
6968 Value should be set to 14
6971 .Bl -bullet -compact
6973 If bit two is set (2) then the detected
6975 content-type will be carried along with the message and be used for
6977 .Va pipe-TYPE/SUBTYPE
6978 is responsible for the MIME part, shall that question arise;
6979 when displaying such a MIME part the part-info will indicate the
6980 overridden content-type by showing a plus-sign
6983 If bit three is set (4) then the counter-evidence is always produced
6984 and a positive result will be used as the MIME type, even forcefully
6985 overriding the parts given MIME type.
6987 If bit four is set (8) then as a last resort the actual content of
6988 .Ql application/octet-stream
6989 parts will be inspected, so that data which looks like plain text can be
6994 .It Va mimetypes-load-control
6995 This option can be used to control which of the
6997 databases are loaded by \*(UA, as furtherly described in the section
6998 .Sx "The mime.types files" .
7001 is part of the option value, then the user's personal
7003 file will be loaded (if it exists); likewise the letter
7005 controls loading of the system wide
7006 .Pa /etc/mime.types ;
7007 directives found in the user file take precedence, letter matching is
7009 If this option is not set \*(UA will try to load both files.
7010 Incorporation of the \*(UA-builtin MIME types cannot be suppressed,
7011 but they will be matched last (the order can be listed via
7014 More sources can be specified by using a different syntax: if the
7015 value string contains an equals sign
7017 then it is instead parsed as a comma-separated list of the described
7020 pairs; the given filenames will be expanded and loaded, and their
7021 content may use the extended syntax that is described in the section
7022 .Sx "The mime.types files" .
7023 Directives found in such files always take precedence (are prepended to
7024 the MIME type cache).
7029 To choose an alternate Mail-Transfer-Agent, set this option to either
7030 the full pathname of an executable (optionally prefixed with a
7032 protocol indicator), or \*(OPally a SMTP protocol URL, e.g., \*(IN
7034 .Dl smtps?://[user[:password]@]server[:port]
7037 .Ql [smtp://]server[:port] . )
7038 The default has been chosen at compie time.
7039 All supported data transfers are executed in child processes, which
7040 run asynchronously, and without supervision, unless either the
7045 If such a child receives a TERM signal, it will abort and
7052 For a file-based MTA it may be necessary to set
7054 in in order to choose the right target of a modern
7057 It will be passed command line arguments from several possible sources:
7060 if set, from the command line if given and the variable
7063 Argument processing of the MTA will be terminated with a
7068 The otherwise occurring implicit usage of the following MTA command
7069 line arguments can be disabled by setting the boolean option
7070 .Va mta-no-default-arguments
7071 (which will also disable passing
7075 (for not treating a line with only a dot
7077 character as the end of input),
7085 option is set); in conjunction with the
7087 command line option \*(UA will also pass
7093 \*(OP \*(UA can send mail over SMTP network connections to a single
7094 defined SMTP smarthost, the access URL of which has to be assigned to
7096 To use this mode it is helpful to read
7097 .Sx "On URL syntax and credential lookup" .
7098 It may be necessary to set the
7100 variable in order to use a specific combination of
7105 with some mail providers.
7108 .Bl -bullet -compact
7110 The plain SMTP protocol (RFC 5321) that normally lives on the
7111 server port 25 and requires setting the
7112 .Va smtp-use-starttls
7113 variable to enter a SSL/TLS encrypted session state.
7114 Assign a value like \*(IN
7115 .Ql smtp://[user[:password]@]server[:port]
7117 .Ql smtp://server[:port] )
7118 to choose this protocol.
7120 The so-called SMTPS which is supposed to live on server port 465
7121 and is automatically SSL/TLS secured.
7122 Unfortunately it never became a standardized protocol and may thus not
7123 be supported by your hosts network service database
7124 \(en in fact the port number has already been reassigned to other
7127 SMTPS is nonetheless a commonly offered protocol and thus can be
7128 chosen by assigning a value like \*(IN
7129 .Ql smtps://[user[:password]@]server[:port]
7131 .Ql smtps://server[:port] ) ;
7132 due to the mentioned problems it is usually necessary to explicitly
7137 Finally there is the SUBMISSION protocol (RFC 6409), which usually
7138 lives on server port 587 and is practically identically to the SMTP
7139 protocol from \*(UA's point of view beside that; it requires setting the
7140 .Va smtp-use-starttls
7141 variable to enter a SSL/TLS secured session state.
7142 Assign a value like \*(IN
7143 .Ql submission://[user[:password]@]server[:port]
7145 .Ql submission://server[:port] ) .
7150 .It Va mta-arguments
7151 Arguments to pass through to a file-based
7153 can be given via this variable, the content of which will be split up in
7154 a vector of arguments, to be joined onto other possible MTA options:
7156 .Dl set mta-arguments='-t -X \&"/tmp/my log\&"'
7159 .It Va mta-no-default-arguments
7160 \*(BO Unless this option is set \*(UA will pass some well known
7161 standard command line options to a file-based
7163 (Mail-Transfer-Agent), see there for more.
7167 Many systems use a so-called
7169 environment to ensure compatibility with
7171 This works by inspecting the name that was used to invoke the mail
7173 If this variable is set then the mailwrapper (the program that is
7174 actually executed when calling the file-based
7176 will treat its contents as that name.
7181 .It Va NAIL_EXTRA_RC
7182 The name of an optional startup file to be read last.
7183 This variable has an effect only if it is set in any of the
7184 .Sx "Resource files" ,
7185 it is not imported from the environment.
7186 Use this file for commands that are not understood by other POSIX
7191 .It Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup
7192 \*(BO\*(IN\*(OP Used to control usage of the users
7194 file for lookup of account credentials, as documented in the section
7195 .Sx "On URL syntax and credential lookup"
7199 .Sx "The .netrc file"
7200 documents the file format.
7212 then \*(UA will read the output of a shell pipe instead of the users
7214 file if this variable is set (to the desired shell command).
7215 This can be used to, e.g., store
7219 .Dl set netrc-pipe='gpg -qd ~/.netrc.pgp'
7223 If this variable has the value
7225 newly created local folders will be in Maildir format.
7229 Checks for new mail in the current folder each time the prompt is shown.
7230 A Maildir folder must be re-scanned to determine if new mail has arrived.
7231 If this variable is set to the special value
7233 then a Maildir folder will not be rescanned completely, but only
7234 timestamp changes are detected.
7238 .It Va on-compose-enter , on-compose-leave
7239 \*(ID Macro hooks which will be executed before compose mode is
7240 entered, and after composing has been finished, respectively.
7241 Please note that this interface is very likely to change in v15, and
7242 should therefore possibly even be seen as experimental.
7244 are by default enabled for these hooks, causing any setting to be
7245 forgotten after the message has been sent.
7246 The following variables will be set temporarily during execution of the
7249 .Bl -tag -compact -width ".It Va compose_subject"
7252 .It Va compose-sender
7254 .It Va compose-to , compose-cc , compose-bcc
7255 The list of receiver addresses as a space-separated list.
7256 .It Va compose-subject
7262 \*(BO Causes the filename given in the
7265 and the sender-based filenames for the
7269 commands to be interpreted relative to the directory given in the
7271 variable rather than to the current directory,
7272 unless it is set to an absolute pathname.
7276 \*(BO If set, each message feed through the command given for
7278 is followed by a formfeed character
7282 .It Va password-USER@HOST , password-HOST , password
7283 \*(IN Variable chain that sets a password, which is used in case none has
7284 been given in the protocol and account-specific URL;
7285 as a last resort \*(UA will ask for a password on the user's terminal if
7286 the authentication method requires a password.
7287 Specifying passwords in a startup file is generally a security risk;
7288 the file should be readable by the invoking user only.
7290 .It Va password-USER@HOST
7291 \*(OU (see the chain above for \*(IN)
7292 Set the password for
7296 If no such variable is defined for a host,
7297 the user will be asked for a password on standard input.
7298 Specifying passwords in a startup file is generally a security risk;
7299 the file should be readable by the invoking user only.
7303 \*(BO Send messages to the
7305 command without performing MIME and character set conversions.
7309 .It Va pipe-TYPE/SUBTYPE
7310 When a MIME message part of type
7312 (case-insensitive) is displayed or quoted,
7313 its text is filtered through the value of this variable interpreted as
7317 forces interpretation of the message part as plain text, e.g.,
7318 .Ql set pipe-application/xml=@
7319 will henceforth display XML
7321 (The same could also be achieved by adding a MIME type marker with the
7324 And \*(OPally MIME type handlers may be defined via
7325 .Sx "The Mailcap files"
7326 \(em corresponding flag strings are shown in parenthesis below.)
7331 can in fact be used to adjust usage and behaviour of a following shell
7332 command specification by appending trigger characters to it, e.g., the
7333 following hypothetical command specification could be used:
7334 .Bd -literal -offset indent
7335 set pipe-X/Y='@*!++=@vim ${NAIL_FILENAME_TEMPORARY}'
7339 .Bl -tag -compact -width ".It Ql __"
7341 Simply by using the special
7343 prefix the MIME type (shell command) handler will only be invoked to
7344 display or convert the MIME part if the message is addressed directly
7345 and alone by itself.
7346 Use this trigger to disable this and always invoke the handler
7347 .Pf ( Cd x-mailx-always ) .
7350 If set the handler will not be invoked when a message is to be quoted,
7351 but only when it will be displayed
7352 .Pf ( Cd x-mailx-noquote ) .
7355 The command will be run asynchronously, i.e., without blocking \*(UA,
7356 which may be a handy way to display a, e.g., PDF file while also
7357 continuing to read the mail message
7358 .Pf ( Cd x-mailx-async ) .
7359 Asynchronous execution implies
7363 The command must be run on an interactive terminal, \*(UA will
7364 temporarily release the terminal to it
7365 .Pf ( Cd needsterminal ) .
7366 This flag is mutual exclusive with
7368 will only be used in interactive mode and implies
7372 Request creation of a zero-sized temporary file, the absolute pathname
7373 of which will be made accessible via the environment variable
7374 .Ev NAIL_FILENAME_TEMPORARY
7375 .Pf ( Cd x-mailx-tmpfile ) .
7376 If this trigger is given twice then the file will be unlinked
7377 automatically by \*(UA when the command loop is entered again at latest
7378 .Pf ( Cd x-mailx-tmpfile-unlink ) .
7379 (Don't use this for asynchronous handlers.)
7382 Normally the MIME part content is passed to the handler via standard
7383 input; if this flag is set then the data will instead be written into
7384 .Ev NAIL_FILENAME_TEMPORARY
7385 .Pf ( Cd x-mailx-tmpfile-fill ) ,
7386 the creation of which is implied; note however that in order to cause
7387 deletion of the temporary file you still have to use two plus signs
7392 To avoid ambiguities with normal shell command content you can use
7393 another at-sign to forcefully terminate interpretation of remaining
7395 (Any character not in this list will have the same effect.)
7399 Some information about the MIME part to be displayed is embedded into
7400 the environment of the shell command:
7403 .Bl -tag -compact -width ".It Ev _AIL__ILENAME__ENERATED"
7406 The MIME content-type of the part, if known, the empty string otherwise.
7409 .It Ev NAIL_CONTENT_EVIDENCE
7411 .Va mime-counter-evidence
7412 includes the carry-around-bit (2), then this will be set to the detected
7413 MIME content-type; not only then identical to
7414 .Ev \&\&NAIL_CONTENT
7418 .It Ev NAIL_FILENAME
7419 The filename, if any is set, the empty string otherwise.
7422 .It Ev NAIL_FILENAME_GENERATED
7426 .It Ev NAIL_FILENAME_TEMPORARY
7427 If temporary file creation has been requested through the command prefix
7428 this variable will be set and contain the absolute pathname of the
7433 The temporary directory that \*(UA uses.
7434 Usually identical to
7436 but guaranteed to be set and usable by child processes;
7437 to ensure the latter condition for
7444 .It Va pipe-EXTENSION
7445 This is identical to
7446 .Va pipe-TYPE/SUBTYPE
7449 (normalized to lowercase using character mappings of the ASCII charset)
7450 names a file extension, e.g.,
7452 Handlers registered using this method take precedence.
7455 .It Va pop3-auth-USER@HOST , pop3-auth-HOST , pop3-auth
7456 \*(OP\*(IN Variable chain that sets the POP3 authentication method.
7457 The only possible value as of now is
7459 which is thus the default.
7462 .Mx Va pop3-bulk-load
7463 .It Va pop3-bulk-load-USER@HOST , pop3-bulk-load-HOST , pop3-bulk-load
7464 \*(BO\*(OP When accessing a POP3 server \*(UA loads the headers of
7465 the messages, and only requests the message bodies on user request.
7466 For the POP3 protocol this means that the message headers will be
7468 If this option is set then \*(UA will download only complete messages
7469 from the given POP3 server(s) instead.
7471 .Mx Va pop3-keepalive
7472 .It Va pop3-keepalive-USER@HOST , pop3-keepalive-HOST , pop3-keepalive
7473 \*(OP POP3 servers close the connection after a period of inactivity;
7474 the standard requires this to be at least 10 minutes,
7475 but practical experience may vary.
7476 Setting this variable to a numeric value greater than
7480 command to be sent each value seconds if no other operation is performed.
7483 .It Va pop3-no-apop-USER@HOST , pop3-no-apop-HOST , pop3-no-apop
7484 \*(BO\*(OP Unless this variable is set the
7486 authentication method will be used when connecting to a POP3 server that
7490 is that the password is not sent in clear text over the wire and that
7491 only a single packet is sent for the user/password tuple.
7493 .Va pop3-no-apop-HOST
7496 .Mx Va pop3-use-starttls
7497 .It Va pop3-use-starttls-USER@HOST , pop3-use-starttls-HOST , pop3-use-starttls
7498 \*(BO\*(OP Causes \*(UA to issue a
7500 command to make an unencrypted POP3 session SSL/TLS encrypted.
7501 This functionality is not supported by all servers,
7502 and is not used if the session is already encrypted by the POP3S method.
7504 .Va pop3-use-starttls-HOST
7508 .It Va print-alternatives
7509 \*(BO When a MIME message part of type
7510 .Ql multipart/alternative
7511 is displayed and it contains a subpart of type
7513 other parts are normally discarded.
7514 Setting this variable causes all subparts to be displayed,
7515 just as if the surrounding part was of type
7516 .Ql multipart/mixed .
7520 The string shown when a command is accepted.
7521 Prompting may be prevented by setting this to the null string
7523 .Pf no Va prompt ) .
7524 If a value is assigned the following \*(UA specific additional sequences
7531 is set, in which case it expands to
7535 is the default value of
7538 which will expand to
7540 if the last command failed and to
7544 which will expand to the name of the currently active
7546 if any, and to the empty string otherwise, and
7548 which will expand to the name of the currently active mailbox.
7549 (Note that the prompt buffer is size-limited, excess is cut off.)
7555 to encapsulate the expansions of the
7559 escape sequences as necessary to correctly display bidirectional text,
7560 this is not true for the final string that makes up
7562 as such, i.e., real BIDI handling is not supported.
7566 \*(BO Suppresses the printing of the version when first invoked.
7570 If set, \*(UA starts a replying message with the original message
7571 prefixed by the value of the variable
7573 Normally, a heading consisting of
7574 .Dq Fromheaderfield wrote:
7575 is put before the quotation.
7580 variable, this heading is omitted.
7583 is assigned, the headers selected by the
7584 .Ic ignore Ns / Ns Ic retain
7585 commands are put above the message body,
7588 acts like an automatic
7594 is assigned, all headers are put above the message body and all MIME
7595 parts are included, making
7597 act like an automatic
7600 .Va quote-as-attachment .
7603 .It Va quote-as-attachment
7604 \*(BO Add the original message in its entirety as a
7606 MIME attachment when replying to a message.
7607 Note this works regardless of the setting of
7612 \*(OP Can be set in addition to
7614 Setting this turns on a more fancy quotation algorithm in that leading
7615 quotation characters are compressed and overlong lines are folded.
7617 can be set to either one or two (space separated) numeric values,
7618 which are interpreted as the maximum (goal) and the minimum line length,
7619 respectively, in a spirit rather equal to the
7621 program, but line-, not paragraph-based.
7622 If not set explicitly the minimum will reflect the goal algorithmically.
7623 The goal can't be smaller than the length of
7625 plus some additional pad.
7626 Necessary adjustments take place silently.
7629 .It Va recipients-in-cc
7630 \*(BO On group replies, specify only the sender of the original mail in
7632 and mention the other recipients in the secondary
7634 By default all recipients of the original mail will be addressed via
7639 If defined, gives the pathname of the folder used to record all outgoing
7641 If not defined, then outgoing mail is not saved.
7642 When saving to this folder fails the message is not sent,
7643 but instead saved to
7647 .It Va record-resent
7648 \*(BO If both this variable and the
7655 commands save messages to the
7657 folder as it is normally only done for newly composed messages.
7660 .It Va reply-in-same-charset
7661 \*(BO If this variable is set \*(UA first tries to use the same
7662 character set of the original message for replies.
7663 If this fails, the mechanism described in
7664 .Sx "Character sets"
7665 is evaluated as usual.
7668 .It Va reply_strings
7669 Can be set to a comma-separated list of (case-insensitive according to
7670 ASCII rules) strings which shall be recognized in addition to the
7673 reply message indicators \(en builtin are
7675 which is mandated by RFC 5322, as well as the german
7680 A list of addresses to put into the
7682 field of the message header.
7683 Members of this list are handled as if they were in the
7688 .It Va reply-to-honour
7691 header is honoured when replying to a message via
7695 This is a quadoption; if set without a value it defaults to
7699 .It Va rfc822-body-from_
7700 \*(BO This variable can be used to force displaying a so-called
7702 line for messages that are embedded into an envelope mail via the
7704 MIME mechanism, for more visual convenience.
7708 \*(BO Enable saving of (partial) messages in
7710 upon interrupt or delivery error.
7714 The number of lines that represents a
7723 line display and scrolling via
7725 If this variable is not set \*(UA falls back to a calculation based upon
7726 the detected terminal window size and the baud rate: the faster the
7727 terminal, the more will be shown.
7728 Overall screen dimensions and pager usage is influenced by the
7729 environment variables
7737 .It Va searchheaders
7738 \*(BO Expand message-list specifiers in the form
7740 to all messages containing the substring
7744 The string search is case insensitive.
7748 \*(OP A comma-separated list of character set names that can be used in
7749 outgoing internet mail.
7750 The value of the variable
7752 is automatically appended to this list of character-sets.
7753 If no character set conversion capabilities are compiled into \*(UA then
7754 the only supported charset is
7757 .Va sendcharsets-else-ttycharset
7758 and refer to the section
7759 .Sx "Character sets"
7760 for the complete picture of character set conversion in \*(UA.
7763 .It Va sendcharsets-else-ttycharset
7764 \*(BO\*(OP If this variable is set, but
7766 is not, then \*(UA acts as if
7768 had been set to the value of the variable
7770 In effect this combination passes through the message data in the
7771 character set of the current locale (given that
7773 hasn't been set manually), i.e., without converting it to the
7775 fallback character set.
7776 Thus, mail message text will be in ISO-8859-1 encoding when send from
7777 within a ISO-8859-1 locale, and in UTF-8 encoding when send from within
7779 If no character set conversion capabilities are available in \*(UA then
7780 the only supported character set is
7785 An address that is put into the
7787 field of outgoing messages, quoting RFC 5322: the mailbox of the agent
7788 responsible for the actual transmission of the message.
7789 This field should normally not be used unless the
7791 field contains more than one address, on which case it is required.
7794 address is handled as if it were in the
7800 \*(OB Predecessor of
7804 .It Va sendmail-arguments
7805 \*(OB Predecessor of
7809 .It Va sendmail-no-default-arguments
7810 \*(OB\*(BO Predecessor of
7811 .Va mta-no-default-arguments .
7814 .It Va sendmail-progname
7815 \*(OB Predecessor of
7820 \*(BO When sending a message wait until the
7822 (including the builtin SMTP one) exits before accepting further commands.
7824 with this variable set errors reported by the MTA will be recognizable!
7825 If the MTA returns a non-zero exit status,
7826 the exit status of \*(UA will also be non-zero.
7830 \*(BO Setting this option causes \*(UA to start at the last message
7831 instead of the first one when opening a mail folder.
7835 \*(BO Causes \*(UA to use the sender's real name instead of the plain
7836 address in the header field summary and in message specifications.
7840 \*(BO Causes the recipient of the message to be shown in the header
7841 summary if the message was sent by the user.
7845 A string for use with the
7851 A string for use with the
7857 Must correspond to the name of a readable file if set.
7858 The file's content is then appended to each singlepart message
7859 and to the first part of each multipart message.
7860 Be warned that there is no possibility to edit the signature for an
7864 .It Va skipemptybody
7865 \*(BO If an outgoing message does not contain any text in its first or
7866 only message part, do not send it but discard it silently (see also the
7872 \*(OP Specifies a directory with CA certificates in PEM (Privacy
7873 Enhanced Mail) format for verification of S/MIME signed messages.
7876 .It Va smime-ca-file
7877 \*(OP Specifies a file with CA certificates in PEM format for
7878 verification of S/MIME signed messages.
7881 .It Va smime-cipher-USER@HOST , smime-cipher
7882 \*(OP Specifies the cipher to use when generating S/MIME encrypted
7883 messages (for the specified account).
7884 RFC 5751 mandates a default of
7887 Possible values are (case-insensitive and) in decreasing cipher strength:
7895 (DES EDE3 CBC, 168 bits; default if
7897 isn't available) and
7901 The actually available cipher algorithms depend on the cryptographic
7902 library that \*(UA uses.
7903 \*(OP Support for more cipher algorithms may be available through
7904 dynamic loading via, e.g.,
7905 .Xr EVP_get_cipherbyname 3
7906 (OpenSSL) if \*(UA has been compiled to support this.
7909 .It Va smime-crl-dir
7910 \*(OP Specifies a directory that contains files with CRLs in PEM format
7911 to use when verifying S/MIME messages.
7914 .It Va smime-crl-file
7915 \*(OP Specifies a file that contains a CRL in PEM format to use when
7916 verifying S/MIME messages.
7919 .It Va smime-encrypt-USER@HOST
7920 \*(OP If this variable is set, messages send to the given receiver are
7921 encrypted before sending.
7922 The value of the variable must be set to the name of a file that
7923 contains a certificate in PEM format.
7925 If a message is sent to multiple recipients,
7926 each of them for whom a corresponding variable is set will receive an
7927 individually encrypted message;
7928 other recipients will continue to receive the message in plain text
7930 .Va smime-force-encryption
7932 It is recommended to sign encrypted messages, i.e., to also set the
7937 .It Va smime-force-encryption
7938 \*(BO\*(OP Causes \*(UA to refuse sending unencrypted messages.
7941 .It Va smime-no-default-ca
7942 \*(BO\*(OP Don't load default CA locations when verifying S/MIME signed
7947 \*(BO\*(OP S/MIME sign outgoing messages with the user's private key
7948 and include the user's certificate as a MIME attachment.
7949 Signing a message enables a recipient to verify that the sender used
7950 a valid certificate,
7951 that the email addresses in the certificate match those in the message
7952 header and that the message content has not been altered.
7953 It does not change the message text,
7954 and people will be able to read the message as usual.
7956 .Va smime-sign-cert , smime-sign-include-certs
7958 .Va smime-sign-message-digest .
7960 .Mx Va smime-sign-cert
7961 .It Va smime-sign-cert-USER@HOST , smime-sign-cert
7962 \*(OP Points to a file in PEM format.
7963 For the purpose of signing and decryption this file needs to contain the
7964 user's private key as well as his certificate.
7968 is always derived from the value of
7970 (or, if that contains multiple addresses,
7972 For the purpose of encryption the recipient's public encryption key
7973 (certificate) is expected; the command
7975 can be used to save certificates of signed messages (the section
7976 .Sx "Signed and encrypted messages with S/MIME"
7977 gives some details).
7978 This mode of operation is usually driven by the specialized form.
7980 When decrypting messages the account is derived from the recipient
7985 of the message, which are searched for addresses for which such
7987 \*(UA always uses the first address that matches,
7988 so if the same message is sent to more than one of the user's addresses
7989 using different encryption keys, decryption might fail.
7991 .Mx Va smime-sign-include-certs
7992 .It Va smime-sign-include-certs-USER@HOST , smime-sign-include-certs
7993 \*(OP If used, this is supposed to a consist of a comma-separated list
7994 of files, each of which containing a single certificate in PEM format to
7995 be included in the S/MIME message in addition to the
7998 This is most useful for long certificate chains if it is desired to aid
7999 the receiving party's verification process.
8000 Note that top level certificates may also be included in the chain but
8001 don't play a role for verification.
8003 .Va smime-sign-cert .
8004 Remember that for this
8006 refers to the variable
8008 (or, if that contains multiple addresses,
8011 .Mx Va smime-sign-message-digest
8012 .It Va smime-sign-message-digest-USER@HOST , smime-sign-message-digest
8013 \*(OP Specifies the message digest to use when signing S/MIME messages.
8014 RFC 5751 mandates a default of
8016 Possible values are (case-insensitive and) in decreasing cipher strength:
8024 The actually available message digest algorithms depend on the
8025 cryptographic library that \*(UA uses.
8026 \*(OP Support for more message digest algorithms may be available
8027 through dynamic loading via, e.g.,
8028 .Xr EVP_get_digestbyname 3
8029 (OpenSSL) if \*(UA has been compiled to support this.
8030 Remember that for this
8032 refers to the variable
8034 (or, if that contains multiple addresses,
8039 \*(OB\*(OP To use the builtin SMTP transport, specify a SMTP URL in
8041 \*(ID For compatibility reasons a set
8043 is used in preference of
8047 .It Va smtp-auth-USER@HOST , smtp-auth-HOST , smtp-auth
8048 \*(OP Variable chain that controls the SMTP
8050 authentication method, possible values are
8056 as well as the \*(OPal methods
8062 method doesn't need any user credentials,
8064 requires a user name and all other methods require a user name and
8072 .Va smtp-auth-password
8074 .Va smtp-auth-user ) .
8079 .Va smtp-auth-USER@HOST :
8080 may override dependent on sender address in the variable
8083 .It Va smtp-auth-password
8084 \*(OP\*(OU Sets the global fallback password for SMTP authentication.
8085 If the authentication method requires a password, but neither
8086 .Va smtp-auth-password
8088 .Va smtp-auth-password-USER@HOST
8090 \*(UA will ask for a password on the user's terminal.
8092 .It Va smtp-auth-password-USER@HOST
8094 .Va smtp-auth-password
8095 for specific values of sender addresses, dependent upon the variable
8098 .It Va smtp-auth-user
8099 \*(OP\*(OU Sets the global fallback user name for SMTP authentication.
8100 If the authentication method requires a user name, but neither
8103 .Va smtp-auth-user-USER@HOST
8105 \*(UA will ask for a user name on the user's terminal.
8107 .It Va smtp-auth-user-USER@HOST
8110 for specific values of sender addresses, dependent upon the variable
8114 .It Va smtp-hostname
8115 \*(OP\*(IN Normally \*(UA uses the variable
8117 to derive the necessary
8119 information in order to issue a
8126 can be used to use the
8128 from the SMTP account
8135 from the content of this variable (or, if that is the empty string,
8137 or the local hostname as a last resort).
8138 This often allows using an address that is itself valid but hosted by
8139 a provider other than which (in
8141 is about to send the message.
8142 Setting this variable also influences the generated
8145 .Mx Va smtp-use-starttls
8146 .It Va smtp-use-starttls-USER@HOST , smtp-use-starttls-HOST , smtp-use-starttls
8147 \*(BO\*(OP Causes \*(UA to issue a
8149 command to make an SMTP
8151 session SSL/TLS encrypted, i.e., to enable transport layer security.
8155 .It Va spam-interface
8156 \*(OP In order to use any of the spam-related commands (like, e.g.,
8158 the desired spam interface must be defined by setting this variable.
8159 Please refer to the manual section
8161 for the complete picture of spam handling in \*(UA.
8162 All or none of the following interfaces may be available:
8164 .Bl -tag -width ".It Ql _ilte_"
8170 .Pf ( Lk http://spamassassin.apache.org SpamAssassin )
8172 Different to the generic filter interface \*(UA will automatically add
8173 the correct arguments for a given command and has the necessary
8174 knowledge to parse the program's output.
8177 will have been compiled into the \*(UA binary if
8182 Shall it be necessary to define a specific connection type (rather than
8183 using a configuration file for that), the variable
8185 can be used as in, e.g.,
8186 .Ql -d server.example.com -p 783 .
8187 It is also possible to specify a per-user configuration via
8189 Note that this interface doesn't inspect the
8191 flag of a message for the command
8195 generic spam filter support via freely configurable hooks.
8196 This interface is meant for programs like
8198 and requires according behaviour in respect to the hooks' exit
8199 status for at least the command
8202 meaning a message is spam,
8206 for unsure and any other return value indicating a hard error);
8207 since the hooks can include shell code snippets diverting behaviour
8208 can be intercepted as necessary.
8210 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
8213 .Va spamfilter-spam ;
8216 contains examples for some programs.
8217 The process environment of the hooks will have the variables
8218 .Ev NAIL_TMPDIR , TMPDIR
8220 .Ev NAIL_FILENAME_GENERATED
8222 Note that spam score support for
8224 isn't supported unless the \*(OPtional regular expression support is
8226 .Va spamfilter-rate-scanscore
8233 \*(OP Messages that exceed this size won't be passed through to the
8235 .Va spam-interface .
8236 If unset or 0, the default of 420000 bytes is used.
8239 .It Va spamc-command
8240 \*(OP The path to the
8244 .Va spam-interface .
8245 Note that the path is not expanded, but used
8247 A fallback path will have been compiled into the \*(UA binary if the
8248 executable had been found during compilation.
8251 .It Va spamc-arguments
8252 \*(OP Even though \*(UA deals with most arguments for the
8255 automatically, it may at least sometimes be desirable to specify
8256 connection-related ones via this variable, e.g.,
8257 .Ql -d server.example.com -p 783 .
8261 \*(OP Specify a username for per-user configuration files for the
8263 .Va spam-interface .
8264 If this is set to the empty string then \*(UA will use the name of the
8273 .It Va spamfilter-ham , spamfilter-noham , \
8274 spamfilter-nospam , spamfilter-rate , spamfilter-spam
8275 \*(OP Command and argument hooks for the
8277 .Va spam-interface .
8280 contains examples for some programs.
8283 .It Va spamfilter-rate-scanscore
8284 \*(OP Because of the generic nature of the
8287 spam scores are not supported for it by default, but if the \*(OPtional
8288 regular expression support is available then setting this variable can
8289 be used to overcome this restriction.
8290 It is interpreted as follows: first a number (digits) is parsed that
8291 must be followed by a semicolon
8293 and an extended regular expression.
8294 Then the latter is used to parse the first output line of the
8296 hook, and, in case the evaluation is successful, the group that has been
8297 specified via the number is interpreted as a floating point scan score.
8301 \*(OP Specifies a directory with CA certificates in PEM (Pricacy
8302 Enhanced Mail) for verification of of SSL/TLS server certificates.
8304 .Xr SSL_CTX_load_verify_locations 3
8305 for more information.
8309 \*(OP Specifies a file with CA certificates in PEM format for
8310 verification of SSL/TLS server certificates.
8312 .Xr SSL_CTX_load_verify_locations 3
8313 for more information.
8316 .It Va ssl-cert-USER@HOST , ssl-cert-HOST , ssl-cert
8317 \*(OP Variable chain that sets the file name for a SSL/TLS client
8318 certificate required by some servers.
8319 This is a direct interface to the
8323 function of the OpenSSL library, if available.
8325 .Mx Va ssl-cipher-list
8326 .It Va ssl-cipher-list-USER@HOST , ssl-cipher-list-HOST , ssl-cipher-list
8327 \*(OP Specifies a list of ciphers for SSL/TLS connections.
8328 This is a direct interface to the
8332 function of the OpenSSL library, if available; see
8334 for more information.
8335 By default \*(UA doesn't set a list of ciphers, which in effect will use a
8337 specific cipher (protocol standards ship with a list of acceptable
8338 ciphers), possibly cramped to what the actually used SSL/TLS library
8339 supports \(en the manual section
8340 .Sx "An example configuration"
8341 also contains a SSL/TLS use case.
8344 .It Va ssl-config-file
8345 \*(OP If this variable is set \*(UA will call
8346 .Xr CONF_modules_load_file 3
8347 to allow OpenSSL to be configured according to the host system wide
8349 If a non-empty value is given then this will be used to specify the
8350 configuration file to be used instead of the global OpenSSL default;
8351 note that in this case it is an error if the file cannot be loaded.
8352 The application name will always be passed as
8357 \*(OP Specifies a file that contains a CRL in PEM format to use when
8358 verifying SSL/TLS server certificates.
8362 \*(OP Specifies a directory that contains files with CRLs in PEM format
8363 to use when verifying SSL/TLS server certificates.
8366 .It Va ssl-key-USER@HOST , ssl-key-HOST , ssl-key
8367 \*(OP Variable chain that sets the file name for the private key of
8368 a SSL/TLS client certificate.
8369 If unset, the name of the certificate file is used.
8370 The file is expected to be in PEM format.
8371 This is a direct interface to the
8375 function of the OpenSSL library, if available.
8378 .It Va ssl-method-USER@HOST , ssl-method-HOST , ssl-method
8379 \*(OB\*(OP Please use the newer and more flexible
8381 instead: if both values are set,
8383 will take precedence!
8384 Can be set to the following values, the actually used
8386 specification to which it is mapped is shown in parenthesis:
8388 .Pf ( Ql -ALL, TLSv1.2 ) ,
8390 .Pf ( Ql -ALL, TLSv1.1 ) ,
8392 .Pf ( Ql -ALL, TLSv1 )
8395 .Pf ( Ql -ALL, SSLv3 ) ;
8400 and thus includes the SSLv3 protocol.
8401 Note that SSLv2 is no longer supported at all.
8404 .It Va ssl-no-default-ca
8405 \*(BO\*(OP Don't load default CA locations to verify SSL/TLS server
8409 .It Va ssl-protocol-USER@HOST , ssl-protocol-HOST , ssl-protocol
8410 \*(OP Specify the used SSL/TLS protocol.
8411 This is a direct interface to the
8415 function of the OpenSSL library, if available;
8416 otherwise an \*(UA internal parser is used which understands the
8417 following subset of (case-insensitive) command strings:
8423 as well as the special value
8425 Multiple specifications may be given via a comma-separated list which
8426 ignores any whitespace.
8429 plus prefix will enable a protocol, a
8431 minus prefix will disable it, so that
8433 will enable only the TLSv1.2 protocol.
8435 It depends upon the used TLS/SSL library which protocols are actually
8436 supported and which protocols are used if
8438 is not set, but note that SSLv2 is no longer supported at all and
8440 Especially for older protocols explicitly securing
8442 may be worthwile, see
8443 .Sx "An example configuration" .
8447 \*(OP Gives the pathname to an entropy daemon socket, see
8449 Not all SSL/TLS libraries support this.
8452 .It Va ssl-rand-file
8453 \*(OP Gives the filename to a file with random entropy data, see
8454 .Xr RAND_load_file 3 .
8455 If this variable is not set, or set to the empty string, or if the
8456 filename expansion failed, then
8457 .Xr RAND_file_name 3
8458 will be used to create the filename if, and only if,
8460 documents that the SSL PRNG is not yet sufficiently seeded.
8461 If \*(UA successfully seeded the SSL PRNG then it'll update the file via
8462 .Xr RAND_write_file 3 .
8463 This variable is only used if
8465 is not set (or not supported by the SSL/TLS library).
8468 .It Va ssl-verify-USER@HOST , ssl-verify-HOST , ssl-verify
8469 \*(OP Variable chain that sets the action to be performed if an error
8470 occurs during SSL/TLS server certificate validation.
8471 Valid (case-insensitive) values are
8473 (fail and close connection immediately),
8475 (ask whether to continue on standard input),
8477 (show a warning and continue),
8479 (do not perform validation).
8485 If only set without an assigned value, then this option inhibits the
8490 header fields that include obvious references to \*(UA.
8491 There are two pitfalls associated with this:
8492 First, the message id of outgoing messages is not known anymore.
8493 Second, an expert may still use the remaining information in the header
8494 to track down the originating mail user agent.
8499 suppression doesn't occur.
8504 (\*(OP) This specifies a comma-separated list of
8509 .Sx "On terminal control and line editor" ,
8510 escape commas with reverse solidus) to be used to overwrite or define
8512 Note that this variable will only be queried once at program startup and
8513 can thus only be specified in resource files or on the command line.
8516 String capabilities form
8518 pairs and are expected unless noted otherwise.
8519 Numerics have to be notated as
8521 where the number is expected in normal decimal notation.
8522 Finally, booleans don't have any value but indicate a true or false
8523 state simply by being defined or not; this indeed means that \*(UA
8524 doesn't support undefining an existing boolean.
8525 String capability values will undergo some expansions before use:
8526 for one notations like
8529 .Ql control-LETTER ,
8530 and for clarification purposes
8532 can be used to specify
8534 (the control notation
8536 could lead to misreadings when a left bracket follows, which it does for
8537 the standard CSI sequence);
8538 finally three letter octal sequences, as in
8541 To specify that a terminal supports 256-colours, and to define sequences
8542 that home the cursor and produce an audible bell, one might write:
8544 .Bd -literal -offset indent
8545 set termcap='Co#256,home=\eE[H,bel=^G'
8549 The following terminal capabilities are or may be meaningful for the
8550 operation of the builtin line editor or \*(UA in general:
8553 .Bl -tag -compact -width yay
8555 .It Cd colors Ns \0or Cd Co
8557 numeric capability specifying the maximum number of colours.
8558 Note that \*(UA doesn't actually care about the terminal beside that,
8559 but always emits ANSI / ISO 6429 escape sequences.
8562 .It Cd rmcup Ns \0or Cd te Ns \0/ Cd smcup Ns \0or Cd ti
8566 respectively: exit and enter the alternative screen
8568 effectively turning \*(UA into a fullscreen application.
8569 To disable that, set (at least) one to the empty string.
8571 .It Cd smkx Ns \0or Cd ks Ns \0/ Cd rmkx Ns \0or Cd ke
8575 respectively: enable and disable the keypad.
8576 This is always enabled if available, because it seems even keyboards
8577 without keypads generate other key codes for, e.g., cursor keys in that
8578 case, and only if enabled we see the codes that we are interested in.
8580 .It Cd ed Ns \0or Cd cd
8584 .It Cd clear Ns \0or Cd cl
8586 clear the screen and home cursor.
8587 (Will be simulated via
8592 .It Cd home Ns \0or Cd ho
8597 .It Cd el Ns \0or Cd ce
8599 clear to the end of line.
8600 (Will be simulated via
8602 plus repetitions of space characters.)
8604 .It Cd hpa Ns \0or Cd ch
8605 .Cd column_address :
8606 move the cursor (to the given column parameter) in the current row.
8607 (Will be simulated via
8613 .Cd carriage_return :
8614 move to the first column in the current row.
8615 The default builtin fallback is
8618 .It Cd cub1 Ns \0or Cd le
8620 move the cursor left one space (non-destructively).
8621 The default builtin fallback is
8624 .It Cd cuf1 Ns \0or Cd nd
8626 move the cursor right one space (non-destructively).
8627 The default builtin fallback is
8629 which is used by most terminals.
8637 Many more capabilities which describe key-sequences are documented for
8641 .It Va termcap-disable
8642 \*(OP Disable any interaction with a terminal control library.
8643 If set only some generic fallback builtins and possibly the content of
8645 describe the terminal to \*(UA.
8647 that this variable will only be queried once at program startup and can
8648 thus only be specified in resource files or on the command line.
8652 If defined, gives the number of lines of a message to be displayed
8655 if unset, the first five lines are printed, if set to 0 the variable
8658 If the value is negative then its absolute value will be used for right
8661 height; (shifting bitwise is like dividing algorithmically, but since
8662 it takes away bits the value decreases pretty fast).
8666 \*(BO If set then the
8668 command series will strip adjacent empty lines and quotations.
8672 The character set of the terminal \*(UA operates on,
8673 and the one and only supported character set that \*(UA can use if no
8674 character set conversion capabilities have been compiled into it,
8675 in which case it defaults to ISO-8859-1 unless it can deduce a value
8679 Refer to the section
8680 .Sx "Character sets"
8681 for the complete picture about character sets.
8684 .It Va typescript-mode
8685 \*(BO A special multiplex variable that disables all variables and
8686 settings which result in behaviour that interferes with running \*(UA in
8689 .Va colour-disable ,
8690 .Va line-editor-disable
8691 and (before startup completed only)
8692 .Va termcap-disable .
8693 Unsetting it doesn't restore the former state of the covered settings.
8697 For a safety-by-default policy \*(UA sets its process
8701 but this variable can be used to override that:
8702 set it to an empty value to don't change the (current) setting,
8703 otherwise the process file mode creation mask is updated to the new value.
8704 Child processes inherit the process file mode creation mask.
8707 .It Va user-HOST , user
8708 \*(IN Variable chain that sets a global fallback user name, which is
8709 used in case none has been given in the protocol and account-specific
8711 This variable defaults to the name of the user who runs \*(UA.
8715 \*(BO Setting this option enables upward compatibility with \*(UA
8716 version 15.0 in respect to which configuration options are available and
8717 how they are handled.
8718 This manual uses \*(IN and \*(OU to refer to the new and the old way of
8719 doing things, respectively.
8723 \*(BO Setting this option, also controllable via the command line option
8725 causes \*(UA to be more verbose, e.g., it will display obsoletion
8726 warnings and SSL/TLS certificate chains.
8727 Even though marked \*(BO this option may be set twice in order to
8728 increase the level of verbosity even more, in which case even details of
8729 the actual message delivery and protocol conversations are shown.
8732 is sufficient to disable verbosity as such.
8738 .It Va version , version-major , version-minor , version-update
8739 \*(RO \*(UA version information: the first variable contains a string
8740 containing the complete version identification, the latter three contain
8741 only digits: the major, minor and update version numbers.
8742 The output of the command
8744 will include this information.
8747 .It Va writebackedited
8748 If this variable is set messages modified using the
8752 commands are written back to the current folder when it is quit;
8753 it is only honoured for writable folders in MBOX format, though.
8754 Note that the editor will be pointed to the raw message content in that
8755 case, i.e., neither MIME decoding nor decryption will have been
8756 performed, and proper RFC 4155
8758 quoting of newly added or edited content is also left as an excercise to
8762 .\" }}} (INTERNAL VARIABLES)
8765 .\" .Sh ENVIRONMENT {{{
8769 .Dq environment variable
8770 should be considered an indication that these variables are either
8771 standardized as vivid parts of process environments, or that they are
8772 commonly found in there.
8773 The process environment is inherited from the
8775 once \*(UA is started, and unless otherwise explicitly noted handling of
8776 the following variables transparently integrates into that of the
8777 .Sx "INTERNAL VARIABLES"
8778 from \*(UA's point of view.
8779 This means that, e.g., they can be managed via
8783 causing automatic program environment updates (to be inherited by
8784 newly created child processes).
8787 In order to transparently integrate other environment variables equally
8788 they need to be imported (linked) with the command
8790 This command can also be used to set and unset non-integrated
8791 environment variables from scratch, sufficient system support provided.
8792 The following example, applicable to a POSIX shell, sets the
8794 environment variable for \*(UA only, and beforehand exports the
8796 in order to affect any further processing in the running shell:
8798 .Bd -literal -offset indent
8799 $ EDITOR="vim -u ${HOME}/.vimrc"
8801 $ COLUMNS=80 \*(uA -R
8804 .Bl -tag -width ".It Ev _AILR_"
8807 The user's preferred width in column positions for the terminal screen
8809 Queried and used once on program startup, actively managed for child
8810 processes and the MLE (see
8811 .Sx "On terminal control and line editor" )
8812 in interactive mode thereafter.
8816 The name of the (mailbox)
8818 to use for saving aborted messages if
8820 is set; this defaults to
8827 is set no output will be generated, otherwise the contents of the file
8832 Pathname of the text editor to use in the
8836 .Sx "TILDE ESCAPES" .
8837 A default editor is used if this value is not defined.
8841 The user's home directory.
8842 This variable is only used when it resides in the process environment.
8849 .It Ev LANG , LC_ALL , LC_COLLATE , LC_CTYPE , LC_MESSAGES
8853 .Sx "Character sets" .
8857 The user's preferred number of lines on a page or the vertical screen
8858 or window size in lines.
8859 Queried and used once on program startup, actively managed for child
8860 processes in interactive mode thereafter.
8864 Pathname of the directory lister to use in the
8866 command when operating on local mailboxes.
8869 (path search through
8874 Upon startup \*(UA will actively ensure that this variable refers to the
8875 name of the user who runs \*(UA, in order to be able to pass a verified
8876 name to any newly created child process.
8880 Is used as the user's primary system mailbox, unless
8884 This is assumed to be an absolute pathname.
8888 \*(OP Overrides the default path search for
8889 .Sx "The Mailcap files" ,
8890 which is defined in the standard RFC 1524 as
8891 .Ql ~/.mailcap:\:/etc/mailcap:\:/usr/etc/mailcap:\:/usr/local/etc/mailcap .
8892 .\" TODO we should have a mailcaps-default virtual RDONLY option!
8893 (\*(UA makes it a configuration option, however.)
8894 Note this is not a search path, but a path search.
8898 Is used as a startup file instead of
8901 When \*(UA scripts are invoked on behalf of other users,
8902 either this variable should be set to
8906 command line option should be used in order to avoid side-effects from
8907 reading their configuration files.
8908 This variable is only used when it resides in the process environment.
8912 The name of the user's mbox file.
8913 A logical subset of the special conventions that are documented for the
8918 The fallback default is
8923 Traditionally this secondary mailbox is used as the file to save
8924 messages from the primary system mailbox that have been read.
8926 .Sx "Message states" .
8929 .It Ev NAIL_NO_SYSTEM_RC
8930 If this variable is set then reading of
8932 at startup is inhibited, i.e., the same effect is achieved as if \*(UA
8933 had been started up with the option
8935 This variable is only used when it resides in the process environment.
8939 \*(IN\*(OP This variable overrides the default location of the user's
8945 Pathname of the program to use for backing the command
8949 variable enforces usage of a pager for output.
8950 The default paginator is
8952 (path search through
8955 \*(UA inspects the contents of this variable: if its contains the string
8957 then a non-existing environment variable
8964 dependent on whether terminal control support is available and whether
8965 that supports full (alternative) screen mode or not (also see
8966 .Sx "On terminal control and line editor" ) .
8970 will optionally be set to
8977 A colon-separated list of directories that is searched by the shell when
8978 looking for commands, e.g.,
8979 .Ql /bin:/usr/bin:/usr/local/bin .
8983 The shell to use for the commands
8989 and when starting subprocesses.
8990 A default shell is used if this option is not defined.
8993 .It Ev SOURCE_DATE_EPOCH
8994 If set, this specifies a time in seconds since the Unix epoch
8995 (1970-01-01) to be used in place of the current time.
8996 This is for the sake of reproduceability of tests, to be used during
8997 development or by software packagers.
9001 \*(OP The terminal type for which output is to be prepared.
9002 For extended colour and font control please refer to
9003 .Sx "Coloured display" ,
9004 and for terminal management in general to
9005 .Sx "On terminal control and line editor" .
9009 Used as directory for temporary files instead of
9012 This variable is only used when it resides in the process environment.
9018 (see there), but this variable is not standardized, should therefore not
9019 be used, and is only corrected if already set.
9023 Pathname of the text editor to use in the
9027 .Sx "TILDE ESCAPES" .
9035 .Bl -tag -width ".It Pa _etc/mime.type_"
9037 File giving initial commands.
9040 System wide initialization file.
9044 \*(OP Personal MIME type handler definition file, see
9045 .Sx "The Mailcap files" .
9046 (RFC 1524 location, the actual path is a configuration option.)
9050 \*(OP System wide MIME type handler definition file, see
9051 .Sx "The Mailcap files" .
9052 (RFC 1524 location, the actual path is a configuration option.)
9055 .It Pa ~/.mime.types
9056 Personal MIME types, see
9057 .Sx "The mime.types files" .
9060 .It Pa /etc/mime.types
9061 System wide MIME types, see
9062 .Sx "The mime.types files" .
9066 \*(IN\*(OP The default location of the users
9068 file \(en the section
9069 .Sx "The .netrc file"
9070 documents the file format.
9073 .\" .Ss "The mime.types files" {{{
9074 .Ss "The mime.types files"
9076 When sending messages \*(UA tries to determine the content type of all
9078 When displaying message content or attachments \*(UA uses the content
9079 type to decide whether it can directly display data or whether it needs
9080 to deal with content handlers.
9081 It learns about M(ultipurpose) I(nternet) M(ail) E(xtensions) types and
9082 how to treat them by reading
9084 files, the loading of which can be controlled by setting the variable
9085 .Va mimetypes-load-control .
9088 can also be used to deal with MIME types.)
9090 files have the following syntax:
9093 .Dl type/subtype extension [extension ...]
9098 are strings describing the file contents, and one or multiple
9100 s, separated by whitespace, name the part of a filename starting after
9101 the last dot (of interest).
9102 Comments may be introduced anywhere on a line with a number sign
9104 causing the remaining line to be discarded.
9106 \*(UA also supports an extended, non-portable syntax in specially
9107 crafted files, which can be loaded via the alternative value syntax of
9108 .Va mimetypes-load-control
9109 and prepends an optional
9113 .Dl [type-marker ]type/subtype extension [extension ...]
9116 The following type markers are supported:
9119 .Bl -tag -compact -offset indent -width ".It Ar _n_u"
9121 Treat message parts with this content as plain text.
9126 Treat message parts with this content as HTML tagsoup.
9127 If the \*(OPal HTML-tagsoup-to-text converter is not available treat
9128 the content as plain text instead.
9132 but instead of falling back to plain text require an explicit content
9133 handler to be defined.
9138 for sending messages:
9140 .Va mime-allow-text-controls ,
9141 .Va mimetypes-load-control .
9142 For reading etc. messages:
9143 .Sx "HTML mail and MIME attachments" ,
9144 .Sx "The Mailcap files" ,
9146 .Va mime-counter-evidence ,
9147 .Va mimetypes-load-control ,
9148 .Va pipe-TYPE/SUBTYPE ,
9149 .Va pipe-EXTENSION .
9152 .\" .Ss "The Mailcap files" {{{
9153 .Ss "The Mailcap files"
9156 .Dq User Agent Configuration Mechanism
9157 which \*(UA \*(OPally supports.
9158 It defines a file format to be used to inform mail user agent programs
9159 about the locally-installed facilities for handling various data
9160 formats, i.e., about commands and how they can be used to display, edit
9161 etc. MIME part contents, as well as a default path search that includes
9162 multiple possible locations of
9166 environment variable that can be used to overwrite that (repeating here
9167 that it is not a search path, but instead a path search specification).
9168 Any existing files will be loaded in sequence, appending any content to
9169 the list of MIME type handler directives.
9173 files consist of a set of newline separated entries.
9174 Comment lines start with a number sign
9176 (in the first column!) and are ignored.
9177 Empty lines are also ignored.
9178 All other lines form individual entries that must adhere to the syntax
9180 To extend a single entry (not comment) its line can be continued on
9181 follow lines if newline characters are
9183 by preceding them with the reverse solidus character
9185 The standard doesn't specify how leading whitespace of follow lines is
9186 to be treated, therefore \*(UA retains it.
9190 entries consist of a number of semicolon
9192 separated fields, and the reverse solidus
9194 character can be used to escape any following character including
9195 semicolon and itself.
9196 The first two fields are mandatory and must occur in the specified
9197 order, the remaining fields are optional and may appear in any order.
9198 Leading and trailing whitespace of content is ignored (removed).
9201 The first field defines the MIME
9203 the entry is about to handle (case-insensitively, and no reverse solidus
9204 escaping is possible in this field).
9205 If the subtype is specified as an asterisk
9207 the entry is meant to match all subtypes of the named type, e.g.,
9209 would match any audio type.
9210 The second field defines the shell command which shall be used to
9212 MIME parts of the given type; it is implicitly called the
9219 shell commands message (MIME part) data is passed via standard input
9220 unless the given shell command includes one or more instances of the
9223 in which case these instances will be replaced with a temporary filename
9224 and the data will have been stored in the file that is being pointed to.
9227 shell commands data is assumed to be generated on standard output unless
9228 the given command includes (one ore multiple)
9230 In any case any given
9232 format is replaced with a(n already) properly quoted filename.
9233 Note that when a command makes use of a temporary file via
9235 then \*(UA will remove it again, as if the
9236 .Cd x-mailx-tmpfile ,
9237 .Cd x-mailx-tmpfile-fill
9239 .Cd x-mailx-tmpfile-unlink
9240 flags had been set; see below for more.
9243 The optional fields either define a shell command or an attribute (flag)
9244 value, the latter being a single word and the former being a keyword
9245 naming the field followed by an equals sign
9247 succeeded by a shell command, and as usual for any
9249 content any whitespace surrounding the equals sign will be removed, too.
9250 Optional fields include the following:
9253 .Bl -tag -width textualnewlines
9255 A program that can be used to compose a new body or body part in the
9262 field, but is to be used when the composing program needs to specify the
9264 header field to be applied to the composed data.
9268 A program that can be used to edit a body or body part in the given
9273 A program that can be used to print a message or body part in the given
9278 Specifies a program to be run to test some condition, e.g., the machine
9279 architecture, or the window system in use, to determine whether or not
9280 this mailcap entry applies.
9281 If the test fails, a subsequent mailcap entry should be sought; also see
9282 .Cd x-mailx-test-once .
9284 .It Cd needsterminal
9285 This flag field indicates that the given shell command must be run on
9286 an interactive terminal.
9287 \*(UA will temporarily release the terminal to the given command in
9288 interactive mode, in non-interactive mode this entry will be entirely
9289 ignored; this flag implies
9290 .Cd x-mailx-noquote .
9292 .It Cd copiousoutput
9293 A flag field which indicates that the output of the
9295 command will be an extended stream of textual output that can be
9296 (re)integrated into \*(UA's normal visual display.
9297 It is mutually exclusive with
9300 .Cd x-mailx-always .
9302 .It Cd textualnewlines
9303 A flag field which indicates that this type of data is line-oriented and
9306 all newlines should be converted to canonical form (CRLF) before
9307 encoding, and will be in that form after decoding.
9311 This field gives a file name format, in which
9313 will be replaced by a random string, the joined combination of which
9314 will be used as the filename denoted by
9315 .Ev NAIL_FILENAME_TEMPORARY .
9316 One could specify that a GIF file being passed to an image viewer should
9317 have a name ending in
9320 .Ql nametemplate=%s.gif .
9321 Note that \*(UA ignores the name template unless that solely specifies
9322 a filename suffix that consists of (ASCII) alphabetic and numeric
9323 characters, the underscore and dot only.
9326 Names a file, in X11 bitmap (xbm) format, which points to an appropriate
9327 icon to be used to visually denote the presence of this kind of data.
9328 This field is not used by \*(UA.
9331 A textual description that describes this type of data.
9333 .It Cd x-mailx-always
9334 Extension flag field that denotes that the given
9336 command shall be executed even if multiple messages will be displayed
9338 Normally messages which require external viewers that produce output
9339 which doesn't integrate into \*(UA's visual display (i.e., don't have
9341 set) have to be addressed directly and individually.
9342 (To avoid cases where, e.g., a thousand PDF viewer instances are spawned
9345 .It Cd x-mailx-even-if-not-interactive
9346 An extension flag test field \(em by default handlers without
9348 are entirely ignored in non-interactive mode, but if this flag is set
9349 then their use will be considered.
9350 It is an error if this flag is set for commands that use the flag
9353 .It Cd x-mailx-noquote
9354 An extension flag field that indicates that even a
9357 command shall not be used to generate message quotes
9358 (as it would be by default).
9360 .It Cd x-mailx-async
9361 Extension flag field that denotes that the given
9363 command shall be executed asynchronously, without blocking \*(UA.
9364 Cannot be used in conjunction with
9367 .It Cd x-mailx-test-once
9368 Extension flag which denotes whether the given
9370 command shall be evaluated once only and the (boolean) result be cached.
9371 This is handy if some global unchanging condition is to be queried, like
9372 .Dq running under the X Window System .
9374 .It Cd x-mailx-tmpfile
9375 Extension flag field that requests creation of a zero-sized temporary
9376 file, the name of which is to be placed in the environment variable
9377 .Ev NAIL_FILENAME_TEMPORARY .
9378 It is an error to use this flag with commands that include a
9382 .It Cd x-mailx-tmpfile-fill
9383 Normally the MIME part content is passed to the handler via standard
9384 input; if this flag is set then the data will instead be written into
9386 .Cd x-mailx-tmpfile .
9387 In order to cause deletion of the temporary file you will have to set
9388 .Cd x-mailx-tmpfile-unlink
9390 It is an error to use this flag with commands that include a
9394 .It Cd x-mailx-tmpfile-unlink
9395 Extension flag field that requests that the temporary file shall be
9396 deleted automatically when the command loop is entered again at latest.
9397 (Don't use this for asynchronous handlers.)
9398 It is an error to use this flag with commands that include a
9400 format, or without also setting
9403 .Cd x-mailx-tmpfile-fill .
9405 .It Cd x-mailx-tmpfile-keep
9408 implies the three tmpfile related flags above, but if you want, e.g.,
9410 and deal with the temporary file yourself, you can add in this flag to
9412 .Cd x-mailx-tmpfile-unlink .
9417 The standard includes the possibility to define any number of additional
9418 entry fields, prefixed by
9420 Flag fields apply to the entire
9422 entry \(em in some unusual cases, this may not be desirable, but
9423 differentiation can be accomplished via separate entries, taking
9424 advantage of the fact that subsequent entries are searched if an earlier
9425 one does not provide enough information.
9428 command needs to specify the
9432 command shall not, the following will help out the latter (with enabled
9436 level \*(UA will show information about handler evaluation):
9438 .Bd -literal -offset indent
9439 application/postscript; ps-to-terminal %s; needsterminal
9440 application/postscript; ps-to-terminal %s; compose=idraw %s
9444 In fields any occurrence of the format string
9446 will be replaced by the
9449 Named parameters from the
9451 field may be placed in the command execution line using
9453 followed by the parameter name and a closing
9456 The entire parameter should appear as a single command line argument,
9457 regardless of embedded spaces; thus:
9459 .Bd -literal -offset indent
9461 Content-type: multipart/mixed; boundary=42
9464 multipart/*; /usr/local/bin/showmulti \e
9465 %t %{boundary} ; composetyped = /usr/local/bin/makemulti
9467 # Executed shell command
9468 /usr/local/bin/showmulti multipart/mixed 42
9472 .\" TODO v15: Mailcap: %n,%F
9473 Note that \*(UA doesn't support handlers for multipart MIME parts as
9474 shown in this example (as of today).
9475 \*(UA doesn't support the additional formats
9479 An example file, also showing how to properly deal with the expansion of
9481 which includes any quotes that are necessary to make it a valid shell
9482 argument by itself and thus will cause undesired behaviour when placed
9483 in additional user-provided quotes:
9485 .Bd -literal -offset indent
9487 text/richtext; richtext %s; copiousoutput
9489 text/x-perl; perl -cWT %s
9493 trap "rm -f ${infile}" EXIT\e; \e
9494 trap "exit 75" INT QUIT TERM\e; \e
9496 x-mailx-async; x-mailx-tmpfile-keep
9498 application/*; echo "This is \e"%t\e" but \e
9499 is 50 \e% Greek to me" \e; < %s head -c 1024 | cat -vET; \e
9500 copiousoutput; x-mailx-noquote
9505 .Sx "HTML mail and MIME attachments" ,
9506 .Sx "The mime.types files" ,
9509 .Va mime-counter-evidence ,
9510 .Va pipe-TYPE/SUBTYPE ,
9511 .Va pipe-EXTENSION .
9514 .\" .Ss "The .netrc file" {{{
9515 .Ss "The .netrc file"
9519 file contains user credentials for machine accounts.
9520 The default location in the user's
9522 directory may be overridden by the
9524 environment variable.
9525 The file consists of space, tabulator or newline separated tokens.
9526 \*(UA implements a parser that supports a superset of the original BSD
9527 syntax, but users should nonetheless be aware of portability glitches
9528 of that file format, shall their
9530 be usable across multiple programs and platforms:
9533 .Bl -bullet -compact
9535 BSD doesn't support single, but only double quotation marks, e.g.,
9536 .Ql password="pass with spaces" .
9538 BSD (only?) supports escaping of single characters via a reverse solidus
9539 (e.g., a space can be escaped via
9541 in- as well as outside of a quoted string.
9543 BSD doesn't require the final quotation mark of the final user input token.
9545 The original BSD (Berknet) parser also supported a format which allowed
9546 tokens to be separated with commas \(en whereas at least Hewlett-Packard
9547 still seems to support this syntax, \*(UA does not!
9549 As a non-portable extension some widely-used programs support
9550 shell-style comments: if an input line starts, after any amount of
9551 whitespace, with a number sign
9553 then the rest of the line is ignored.
9555 Whereas other programs may require that the
9557 file is accessible by only the user if it contains a
9563 \*(UA will always require these strict permissions.
9567 Of the following list of supported tokens \*(UA only uses (and caches)
9572 At runtime the command
9574 can be used to control \*(UA's
9578 .Bl -tag -width password
9579 .It Cd machine Ar name
9580 The hostname of the entries' machine, lowercase-normalized by \*(UA
9582 Any further file content, until either end-of-file or the occurrence
9587 first-class token is bound (only related) to the machine
9590 As an extension that shouldn't be the cause of any worries
9591 \*(UA supports a single wildcard prefix for
9593 .Bd -literal -offset indent
9594 machine *.example.com login USER password PASS
9595 machine pop3.example.com login USER password PASS
9596 machine smtp.example.com login USER password PASS
9602 .Ql pop3.example.com ,
9606 .Ql local.smtp.example.com .
9607 Note that in the example neither
9608 .Ql pop3.example.com
9610 .Ql smtp.example.com
9611 will be matched by the wildcard, since the exact matches take
9612 precedence (it is however faster to specify it the other way around).
9617 except that it is a fallback entry that is used shall none of the
9618 specified machines match; only one default token may be specified,
9619 and it must be the last first-class token.
9621 .It Cd login Ar name
9622 The user name on the remote machine.
9624 .It Cd password Ar string
9625 The user's password on the remote machine.
9627 .It Cd account Ar string
9628 Supply an additional account password.
9629 This is merely for FTP purposes.
9631 .It Cd macdef Ar name
9633 A macro is defined with the specified
9635 it is formed from all lines beginning with the next line and continuing
9636 until a blank line is (consecutive newline characters are) encountered.
9639 entries cannot be utilized by multiple machines, too, but must be
9640 defined following the
9642 they are intended to be used with.)
9645 exists, it is automatically run as the last step of the login process.
9646 This is merely for FTP purposes.
9653 .\" .Sh EXAMPLES {{{
9656 .\" .Ss "An example configuration" {{{
9657 .Ss "An example configuration"
9659 .Bd -literal -offset indent
9660 # This example assumes v15.0 compatibility mode
9663 # Where are the up-to-date SSL certificates?
9664 #set ssl-ca-dir=/etc/ssl/certs
9665 set ssl-ca-file=/etc/ssl/certs/ca-certificates.crt
9667 # (Since we manage up-to-date ones explicitly, don't use any,
9668 # possibly outdated, default certificates shipped with OpenSSL)
9669 set ssl-no-default-ca
9671 # Don't use protocols older than TLS v1.2.
9672 # Change this only when the remote server doesn't support it:
9673 # maybe use ssl-protocol-HOST (or -USER@HOST) syntax to define
9674 # such explicit exceptions, then
9675 set ssl-protocol='-ALL,+TLSv1.2'
9677 # Explicitly define the list of ciphers, which may improve security,
9678 # especially with protocols older than TLS v1.2. See ciphers(1).
9679 # Including "@STRENGTH" will sort the final list by algorithm strength.
9680 # In reality it is possibly best to only use ssl-cipher-list-HOST
9681 # (or -USER@HOST), as necessary, again..
9682 set ssl-cipher-list=TLSv1.2:!aNULL:!eNULL:!MEDIUM:!LOW:!EXPORT:@STRENGTH
9683 # ALL:!aNULL:!MEDIUM:!LOW:!MD5:!RC4:!EXPORT:@STRENGTH
9685 # Request strict transport security checks!
9686 set ssl-verify=strict
9688 # Essential setting: select allowed character sets
9689 set sendcharsets=utf-8,iso-8859-1
9691 # A very kind option: when replying to a message, first try to
9692 # use the same encoding that the original poster used herself!
9693 set reply-in-same-charset
9695 # When replying to or forwarding a message the comment and name
9696 # parts of email addresses are removed unless this variable is set
9699 # When sending messages, wait until the Mail-Transfer-Agent finishs.
9700 # Only like this you'll be able to see errors reported through the
9701 # exit status of the MTA (including the builtin SMTP one)!
9704 # Only use builtin MIME types, no mime.types(5) files
9705 set mimetypes-load-control
9707 # Default directory where we act in (relative to $HOME)
9709 # A leading "+" (often) means: under *folder*
9710 # *record* is used to save copies of sent messages
9711 set MBOX=+mbox.mbox record=+sent.mbox DEAD=+dead.txt
9713 # Make "file mymbox" and "file myrec" go to..
9714 shortcut mymbox %:+mbox.mbox myrec +sent.mbox
9716 # Not really optional, e.g., for S/MIME
9717 set from='Your Name <address@exam.ple>'
9719 # It may be necessary to set hostname and/or smtp-hostname
9720 # if the "SERVER" of mta and "domain" of from don't match.
9721 # The `urlencode' command can be used to encode USER and PASS
9722 set mta=(smtps?|submission)://[USER[:PASS]@]SERVER[:PORT] \e
9723 smtp-auth=login/plain... \e
9726 # Never refuse to start into interactive mode, and more
9728 colour-pager crt= \e
9729 followup-to followup-to-honour=ask-yes \e
9730 history-file=+.\*(uAhist history-size=-1 history-gabby \e
9731 mime-counter-evidence=0xE \e
9732 prompt='?\e?[\e$ \e@]\e& ' \e
9733 reply-to-honour=ask-yes \e
9736 # When `t'yping messages, show only these headers
9737 # (use `T'ype for all headers and `S'how for raw message)
9738 retain date from to cc subject
9740 # Some mailing lists
9741 mlist '@xyz-editor\e.xyz$' '@xyzf\e.xyz$'
9742 mlsubscribe '^xfans@xfans\e.xyz$'
9744 # A real life example of a very huge free mail provider
9746 set folder=~/spool/XooglX inbox=+syste.mbox sent=+sent
9747 set from='Your Name <address@examp.ple>'
9748 set mta=smtp://USER:PASS@smtp.gmXil.com smtp-use-starttls
9751 # Here is a pretty large one which does not allow sending mails
9752 # if there is a domain name mismatch on the SMTP protocol level,
9753 # which would bite us if the value of from does not match, e.g.,
9754 # for people who have a sXXXXeforge project and want to speak
9755 # with the mailing list under their project account (in from),
9756 # still sending the message through their normal mail provider
9758 set folder=~/spool/XandeX inbox=+syste.mbox sent=+sent
9759 set from='Your Name <address@exam.ple>'
9760 set mta=smtps://USER:PASS@smtp.yaXXex.ru:465 \e
9761 hostname=yaXXex.com smtp-hostname=
9764 # Create some new commands so that, e.g., `ls /tmp' will..
9765 wysh ghost lls '!ls ${LS_COLOR_FLAG} -aFlrS'
9766 wysh ghost llS '!ls ${LS_COLOR_FLAG} -aFlS'
9767 wysh ghost ls '!ls ${LS_COLOR_FLAG} -aFrS'
9768 wysh ghost lS '!ls ${LS_COLOR_FLAG} -aFS'
9769 wysh ghost lla '!ls ${LS_COLOR_FLAG} -aFlr'
9770 wysh ghost llA '!ls ${LS_COLOR_FLAG} -aFl'
9771 wysh ghost la '!ls ${LS_COLOR_FLAG} -aFr'
9772 wysh ghost lA '!ls ${LS_COLOR_FLAG} -aF'
9773 wysh ghost ll '!ls ${LS_COLOR_FLAG} -aFltr'
9774 wysh ghost lL '!ls ${LS_COLOR_FLAG} -aFlt'
9775 wysh ghost l '!ls ${LS_COLOR_FLAG} -aFtr'
9776 wysh ghost L '!ls ${LS_COLOR_FLAG} -aFt'
9778 # We don't support gpg(1) directly yet. But simple --clearsign'd
9779 # message parts can be dealt with as follows:
9781 wysh set pipe-text/plain=$'@*#++=@\e
9782 < "${NAIL_FILENAME_TEMPORARY}" awk \e
9783 -v TMPFILE="${NAIL_FILENAME_TEMPORARY}" \e'\e
9785 /^-----BEGIN PGP SIGNED MESSAGE-----/,/^$/{\e
9788 print "--- GPG --verify ---";\e
9789 system("gpg --verify " TMPFILE " 2>&1");\e
9790 print "--- GPG --verify ---";\e
9794 /^-----BEGIN PGP SIGNATURE-----/,\e
9795 /^-----END PGP SIGNATURE-----/{\e
9805 !printf 'Key IDs to gpg --recv-keys: ';\e
9807 gpg --recv-keys ${keyids};
9813 When storing passwords in
9815 appropriate permissions should be set on this file with
9816 .Ql $ chmod 0600 \*(ur .
9819 is available user credentials can be stored in the central
9821 file instead; e.g., here is a different version of the example account
9822 that sets up SMTP and POP3:
9824 .Bd -literal -offset indent
9826 set folder=~/spool/XandeX inbox=+syste.mbox sent=+sent
9827 set from='Your Name <address@exam.ple>'
9829 # Load an encrypted ~/.netrc by uncommenting the next line
9830 #set netrc-pipe='gpg -qd ~/.netrc.pgp'
9832 set mta=smtps://smtp.yXXXXx.ru:465 \e
9833 smtp-hostname= hostname=yXXXXx.com
9834 set pop3-keepalive=240 pop3-no-apop-pop.yXXXXx.ru
9835 ghost xp fi pop3s://pop.yXXXXx.ru
9844 .Bd -literal -offset indent
9845 machine *.yXXXXx.ru login USER password PASS
9849 This configuration should now work just fine:
9852 .Dl $ echo text | \*(uA -vv -AXandeX -s Subject user@exam.ple
9855 .\" .Ss "Signed and encrypted messages with S/MIME" {{{
9856 .Ss "Signed and encrypted messages with S/MIME"
9858 \*(OP S/MIME provides two central mechanisms:
9859 message signing and message encryption.
9860 A signed message contains some data in addition to the regular text.
9861 The data can be used to verify that the message was sent using a valid
9862 certificate, that the sender's address in the message header matches
9863 that in the certificate, and that the message text has not been altered.
9864 Signing a message does not change its regular text;
9865 it can be read regardless of whether the recipient's software is able to
9869 It is thus usually possible to sign all outgoing messages if so desired.
9870 Encryption, in contrast, makes the message text invisible for all people
9871 except those who have access to the secret decryption key.
9872 To encrypt a message, the specific recipient's public encryption key
9874 It is therefore not possible to send encrypted mail to people unless their
9875 key has been retrieved from either previous communication or public key
9877 A message should always be signed before it is encrypted.
9878 Otherwise, it is still possible that the encrypted message text is
9882 A central concept to S/MIME is that of the certification authority (CA).
9883 A CA is a trusted institution that issues certificates.
9884 For each of these certificates it can be verified that it really
9885 originates from the CA, provided that the CA's own certificate is
9887 A set of CA certificates is usually delivered with OpenSSL and installed
9889 If you trust the source of your OpenSSL software installation,
9890 this offers reasonable security for S/MIME on the Internet.
9892 .Va ssl-no-default-ca
9896 .Va smime-ca-dir . )
9897 In general, a certificate cannot be more secure than the method its CA
9898 certificate has been retrieved with, though.
9899 Thus if you download a CA certificate from the Internet,
9900 you can only trust the messages you verify using that certificate as
9901 much as you trust the download process.
9904 The first thing you need for participating in S/MIME message exchange is
9905 your personal certificate, including a private key.
9906 The certificate contains public information, in particular your name and
9907 your email address(es), and the public key that is used by others to
9908 encrypt messages for you,
9909 and to verify signed messages they supposedly received from you.
9910 The certificate is included in each signed message you send.
9911 The private key must be kept secret.
9912 It is used to decrypt messages that were previously encrypted with your
9913 public key, and to sign messages.
9916 For personal use it is recommended that you get a S/MIME certificate
9917 from one of the major CAs on the Internet using your WWW browser.
9918 Many CAs offer such certificates for free.
9920 .Lk https://www.CAcert.org
9921 which issues client and server certificates to members of their
9922 community for free; their root certificate
9923 .Pf ( Lk https://\:www.cacert.org/\:certs/\:root.crt )
9924 is often not in the default set of trusted CA root certificates, though,
9925 which means you will have to download their root certificate separately
9926 and ensure it is part of our S/MIME certificate validation chain by
9929 or as a vivid member of the
9931 But let's take a step-by-step tour on how to setup S/MIME with
9932 a certificate from CAcert.org despite this situation!
9935 First of all you will have to become a member of the CAcert.org
9936 community, simply by registrating yourself via the web interface.
9937 Once you are, create and verify all email addresses you want to be able
9938 to create signed and encrypted messages for/with using the corresponding
9939 entries of the web interface.
9940 Now ready to create S/MIME certificates, so let's create a new
9941 .Dq client certificate ,
9942 ensure to include all email addresses that should be covered by the
9943 certificate in the following web form, and also to use your name as the
9947 Create a private key and a certificate request on your local computer
9948 (please see the manual pages of the used commands for more in-depth
9949 knowledge on what the used arguments etc. do):
9952 .Dl openssl req -nodes -newkey rsa:4096 -keyout key.pem -out creq.pem
9955 Afterwards copy-and-paste the content of
9957 into the certificate-request (CSR) field of the web form on the
9958 CAcert.org website (you may need to unfold some
9959 .Dq advanced options
9960 to see the corresponding text field).
9961 This last step will ensure that your private key (which never left your
9962 box) and the certificate belong together (through the public key that
9963 will find its way into the certificate via the certificate-request).
9964 You are now ready and can create your CAcert certified certificate.
9965 Download and store or copy-and-paste it as
9970 In order to use your new S/MIME setup you will have to create
9971 a combined private key/public key (certificate) file:
9974 .Dl cat key.pem pub.crt > ME@HERE.com.paired
9977 This is the file \*(UA will work with.
9978 If you have created your private key with a passphrase then \*(UA will
9979 ask you for it whenever a message is signed or decrypted.
9980 Set the following variables to henceforth use S/MIME (setting
9982 is of interest for verification only):
9984 .Bd -literal -offset indent
9985 set smime-ca-file=ALL-TRUSTED-ROOT-CERTS-HERE \e
9986 smime-sign-cert=ME@HERE.com.paired \e
9987 smime-sign-message-digest=SHA256 \e
9992 From each signed message you send, the recipient can fetch your
9993 certificate and use it to send encrypted mail back to you.
9994 Accordingly if somebody sends you a signed message, you can do the same,
9997 command to check the validity of the certificate.
10000 Variables of interest for S/MIME signing:
10002 .Va smime-ca-file ,
10003 .Va smime-crl-dir ,
10004 .Va smime-crl-file ,
10005 .Va smime-no-default-ca ,
10007 .Va smime-sign-cert ,
10008 .Va smime-sign-include-certs
10010 .Va smime-sign-message-digest .
10013 After it has been verified save the certificate via
10015 and tell \*(UA that it should use it for encryption for further
10016 communication with that somebody:
10018 .Bd -literal -offset indent
10020 set smime-encrypt-USER@HOST=FILENAME \e
10021 smime-cipher-USER@HOST=AES256
10025 Additional variables of interest for S/MIME en- and decryption:
10028 .Va smime-encrypt-USER@HOST .
10031 You should carefully consider if you prefer to store encrypted messages
10033 If you do, anybody who has access to your mail folders can read them,
10034 but if you do not, you might be unable to read them yourself later if
10035 you happen to lose your private key.
10038 command saves messages in decrypted form, while the
10042 commands leave them encrypted.
10045 Note that neither S/MIME signing nor encryption applies to message
10046 subjects or other header fields yet.
10047 Thus they may not contain sensitive information for encrypted messages,
10048 and cannot be trusted even if the message content has been verified.
10049 When sending signed messages,
10050 it is recommended to repeat any important header information in the
10054 .\" .Ss "Using CRLs with S/MIME or SSL/TLS" {{{
10055 .Ss "Using CRLs with S/MIME or SSL/TLS"
10057 \*(OP Certification authorities (CAs) issue certificate revocation
10058 lists (CRLs) on a regular basis.
10059 These lists contain the serial numbers of certificates that have been
10060 declared invalid after they have been issued.
10061 Such usually happens because the private key for the certificate has
10063 because the owner of the certificate has left the organization that is
10064 mentioned in the certificate, etc.
10065 To seriously use S/MIME or SSL/TLS verification,
10066 an up-to-date CRL is required for each trusted CA.
10067 There is otherwise no method to distinguish between valid and
10068 invalidated certificates.
10069 \*(UA currently offers no mechanism to fetch CRLs, nor to access them on
10070 the Internet, so you have to retrieve them by some external mechanism.
10073 \*(UA accepts CRLs in PEM format only;
10074 CRLs in DER format must be converted, like, e.\|g.:
10077 .Dl $ openssl crl \-inform DER \-in crl.der \-out crl.pem
10080 To tell \*(UA about the CRLs, a directory that contains all CRL files
10081 (and no other files) must be created.
10086 variables, respectively, must then be set to point to that directory.
10087 After that, \*(UA requires a CRL to be present for each CA that is used
10088 to verify a certificate.
10091 .\" .Ss "Handling spam" {{{
10092 .Ss "Handling spam"
10094 \*(OP \*(UA can make use of several spam interfaces for the purpose of
10095 identification of, and, in general, dealing with spam messages.
10096 A precondition of most commands in order to function is that the
10098 variable is set to one of the supported interfaces.
10099 Once messages have been identified as spam their (volatile)
10101 state can be prompted: the
10105 message specifications will address respective messages and their
10107 entries will be used when displaying the
10109 in the header display.
10114 rates the given messages and sets their
10117 If the spam interface offers spam scores those can also be displayed in
10118 the header display by including the
10128 will interact with the Bayesian filter of the chosen interface and learn
10129 the given messages as
10133 respectively; the last command can be used to cause
10135 of messages; it adheres to their current
10137 state and thus reverts previous teachings.
10142 will simply set and clear, respectively, the mentioned volatile
10144 message flag, without any interface interaction.
10153 requires a running instance of the
10155 server in order to function, started with the option
10157 shall Bayesian filter learning be possible.
10159 .Bd -literal -offset indent
10160 $ spamd -i localhost:2142 -i /tmp/.spamsock -d [-L] [-l]
10161 $ spamd --listen=localhost:2142 --listen=/tmp/.spamsock \e
10162 --daemonize [--local] [--allow-tell]
10166 Thereafter \*(UA can make use of these interfaces:
10168 .Bd -literal -offset indent
10169 $ \*(uA -Sspam-interface=spamc -Sspam-maxsize=500000 \e
10170 -Sspamc-command=/usr/local/bin/spamc \e
10171 -Sspamc-arguments="-U /tmp/.spamsock" -Sspamc-user=
10173 $ \*(uA -Sspam-interface=spamc -Sspam-maxsize=500000 \e
10174 -Sspamc-command=/usr/local/bin/spamc \e
10175 -Sspamc-arguments="-d localhost -p 2142" -Sspamc-user=
10179 Using the generic filter approach allows usage of programs like
10181 Here is an example, requiring it to be accessible via
10184 .Bd -literal -offset indent
10185 $ \*(uA -Sspam-interface=filter -Sspam-maxsize=500000 \e
10186 -Sspamfilter-ham="bogofilter -n" \e
10187 -Sspamfilter-noham="bogofilter -N" \e
10188 -Sspamfilter-nospam="bogofilter -S" \e
10189 -Sspamfilter-rate="bogofilter -TTu 2>/dev/null" \e
10190 -Sspamfilter-spam="bogofilter -s" \e
10191 -Sspamfilter-rate-scanscore="1;^(.+)$"
10195 Because messages must exist on local storage in order to be scored (or
10196 used for Bayesian filter training), it is possibly a good idea to
10197 perform the local spam check last:
10199 .Bd -literal -offset indent
10200 define spamdelhook {
10202 spamset (header x-dcc-brand-metrics "bulk")
10203 # Server-side spamassassin(1)
10204 spamset (header x-spam-flag "YES")
10205 del :s # TODO we HAVE to be able to do `spamrate :u ! :sS'
10206 move :S +maybe-spam
10209 move :S +maybe-spam
10211 set folder-hook-FOLDER=spamdelhook
10215 See also the documentation for the variables
10216 .Va spam-interface , spam-maxsize ,
10217 .Va spamc-command , spamc-arguments , spamc-user ,
10218 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
10221 .Va spamfilter-rate-scanscore .
10229 In general it is a good idea to turn on
10235 twice) if something doesn't work well.
10236 Very often a diagnostic message can be produced that leads to the
10237 problems' solution.
10239 .\" .Ss "\*(UA shortly hangs on startup" {{{
10240 .Ss "\*(UA shortly hangs on startup"
10242 This can have two reasons, one is the necessity to wait for a file lock
10243 and can't be helped, the other being that \*(UA calls the function
10245 in order to query the nodename of the box (sometimes the real one is
10246 needed instead of the one represented by the internal variable
10248 You may have varying success by ensuring that the real hostname and
10252 or, more generally, that the name service is properly setup \(en
10255 return what you'd expect?
10256 Does this local hostname has a domain suffix?
10257 RFC 6762 standardized the link-local top-level domain
10261 .\" .Ss "\*(UA exits quick, and output is cleared away" {{{
10262 .Ss "\*(UA exits quick, and output is cleared away"
10264 When this happens even with
10266 set, then this most likely indicates a problem with the creation of
10267 so-called dotlock files: setting
10268 .Va dotlock-ignore-error
10269 should overcome this situation.
10270 This only avoids symptoms, it doesn't address the problem, though.
10271 Since the output is cleared away \*(UA has support for
10272 .Sx "On terminal control and line editor" ,
10273 and switches to the
10275 which causes the output clearance: by doing
10276 .Ql set termcap='smcup='
10277 this mode can be suppressed, and by setting
10279 (twice) the actual problem should be reported.
10282 .\" .Ss "I can't login to Google mail aka GMail" {{{
10283 .Ss "I can't login to Google mail aka GMail"
10285 Since 2014 some free service providers classify programs as
10287 unless they use a special authentification method (OAuth 2.0) which
10288 wasn't standardized for non-HTTP protocol authentication token query
10289 until August 2015 (RFC 7628).
10292 Different to Kerberos / GSSAPI, which is developed since the mid of the
10293 1980s, where a user can easily create a local authentication ticket for
10294 her- and himself with the locally installed
10296 program, that protocol has no such local part but instead requires
10297 a world-wide-web query to create or fetch a token; since there is no
10298 local cache this query has to be performed whenever \*(UA is invoked
10299 from the command line (in interactive sessions situation may differ).
10302 \*(UA doesn't support OAuth.
10303 Because of this it is necessary to declare \*(UA a
10304 .Dq less secure app
10305 (on the providers account web page) in order to read and send mail.
10306 However, it also seems possible to take the following steps instead:
10311 give the provider the number of a mobile phone,
10314 .Dq 2-Step Verification ,
10316 create an application specific password (16 characters), and
10318 use that special password instead of your real Google account password in
10319 \*(UA (for more on that see the section
10320 .Sx "On URL syntax and credential lookup" ) .
10324 .\" .Ss "Not \(dqdefunctional\(dq, but the editor key won't work" {{{
10325 .Ss "Not \(dqdefunctional\(dq, but the editor key won't work"
10327 It can happen that the terminal library (see
10328 .Sx "On terminal control and line editor",
10331 reports different codes than the terminal really sends, in which case
10332 \*(UA will tell that a key binding is functional, but won't be able to
10333 recognize it because the received data doesn't match anything expected.
10334 The verbose listing of
10336 ings will show the byte sequences that are expected.
10339 To overcome the situation, use, e.g., the program
10341 in conjunction with the
10343 flag if available, to see the byte sequences which are actually produced
10344 by keypresses, and use the variable
10346 to make \*(UA aware of them.
10347 E.g., the terminal this is typed on produces some false sequences, here
10348 an example showing the shifted home key:
10350 .Bd -literal -offset indent
10353 # 1B 5B=[ 31=1 3B=; 32=2 48=H
10358 ? \*(uA -v -Stermcap='kHOM=\eE[H'
10367 .\" .Sh "SEE ALSO" {{{
10377 .Xr spamassassin 1 ,
10386 .Xr mailwrapper 8 ,
10391 .\" .Sh HISTORY {{{
10394 M. Douglas McIlroy writes in his article
10395 .Dq A Research UNIX Reader: Annotated Excerpts \
10396 from the Programmer's Manual, 1971-1986
10399 command already appeared in First Edition
10403 .Bd -ragged -offset indent
10404 Electronic mail was there from the start.
10405 Never satisfied with its exact behavior, everybody touched it at one
10406 time or another: to assure the safety of simultaneous access, to improve
10407 privacy, to survive crashes, to exploit uucp, to screen out foreign
10408 freeloaders, or whatever.
10409 Not until v7 did the interface change (Thompson).
10410 Later, as mail became global in its reach, Dave Presotto took charge and
10411 brought order to communications with a grab-bag of external networks
10417 Mail was written in 1978 by Kurt Shoens and developed as part of the
10420 distribution until 1995.
10421 Mail has then seen further development in open source
10423 variants, noticeably by Christos Zoulas in
10425 Basing upon this Nail, later Heirloom Mailx, was developed by Gunnar
10426 Ritter in the years 2000 until 2008.
10427 Since 2012 S-nail is maintained by Steffen (Daode) Nurpmeso.
10428 This man page is derived from
10429 .Dq The Mail Reference Manual
10430 that was originally written by Kurt Shoens.
10436 .An "Kurt Shoens" ,
10437 .An "Edward Wang" ,
10438 .An "Keith Bostic" ,
10439 .An "Christos Zoulas" ,
10440 .An "Gunnar Ritter" ,
10441 .An "Steffen Nurpmeso" Aq Mt s-nail-users@lists.sourceforge.net
10443 .Mt s-mailx@sdaoden.eu ) .
10446 .\" .Sh CAVEATS {{{
10449 \*(ID Interrupting an operation via
10453 is often problematic: many library functions cannot deal with the
10455 that this software (still) performs.
10458 The SMTP and POP3 protocol support of \*(UA is very basic.
10459 Also, if it fails to contact its upstream SMTP server, it will not make
10460 further attempts to transfer the message at a later time (setting
10465 If this is a concern, it might be better to set up a local SMTP server
10466 that is capable of message queuing.
10472 After deleting some message of a POP3 mailbox the header summary falsely
10473 claims that there are no messages to display, you need to perform
10474 a scroll or dot movement to restore proper state.
10476 In threaded display a power user may encounter crashes very
10477 occasionally (this is may and very).
10481 in the source repository lists future directions.