1 .\" Copyright (c) 1980, 1990, 1993
2 .\" The Regents of the University of California. All rights reserved.
4 .\" Gunnar Ritter. All rights reserved.
5 .\" Copyright (c) 2012 - 2014 Steffen (Daode) Nurpmeso <sdaoden@users.sf.net>.
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17 .\" This product includes software developed by the University of
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19 .\" This product includes software developed by Gunnar Ritter
20 .\" and his contributors.
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41 .ds UV \\%S-nail dirty
45 .\" If not ~/.mailrc, it breaks POSIX compatibility. And adjust main.c.
50 .ds OU [no v15-compat]
55 .Nd send and receive Internet mail
62 .Op Fl a Ar attachment
65 .Op Fl O Ar mta-option
66 .Op Fl q Ar quote-file
68 .Op Fl S Ar variable Ns Op Ns = Ns Ar value
77 .Op Fl S Ar variable Ns Op Ns = Ns Ar value
85 .Op Fl S Ar variable Ns Op Ns = Ns Ar value
91 .Bd -filled -offset indent -compact
92 .Sy Compatibility note:
93 \*(UA and part of its configuration syntax will change in v15.0.
94 Until then there will exist a partial but growing number of
95 backward and forward compatibility configuration options.
96 To choose the new syntax and behaviour already today, the binary option
99 The manual will refer to it via \*(IN and \*(OU as necessary.
102 \*(UA is a mail processing system with a command syntax reminiscent of
104 with lines replaced by messages.
105 It is intended to provide the functionality of the POSIX
107 command and offers (mostly optional) extensions for line editing, IDNA,
108 MIME, S/MIME, SMTP and POP3 (and IMAP).
109 It is usable as a mail batch language.
111 In the following list of supported command line options,
119 are implemented by means of setting the respective option, as via
122 .Bl -tag -width ".Fl A Ar account"
126 command (see below) for
128 after the startup files have been read.
130 Attach the given file to the message.
131 The same filename conventions as described in the section
135 Make standard input and standard output line-buffered.
137 Send blind carbon copies to the given list of addresses.
139 below goes into more detail on that.
141 Send carbon copies to the given list of addresses.
149 variable, which enables debug messages and disables message delivery.
150 Note that this is not a real `sandbox' mode.
154 variable and thus discard messages with an empty message part body.
155 This is useful for sending messages from scripts.
157 Just check if mail is present in the system mailbox.
158 If yes, return an exit status of zero, a non-zero value otherwise.
160 Save the message to send in a file named after the local part of the
161 first recipient's address.
163 Read in the contents of the user's mbox (or the specified file)
165 when \*(UA is quit, it writes undeleted messages back to this file.
168 is interpreted as described for the
173 is not a direct argument to the flag
175 but is instead taken from the command line after option processing has
178 Print a header summary of all messages and exit.
179 A configurable summary view is available via the
185 variable to ignore tty interrupt signals.
186 .It Fl L Ar spec-list
187 Print a header summary of only those messages that match the given
191 .Sx "Specifying messages"
196 option has been given in addition to
198 then printing of the header summary is suppressed,
199 and \*(UA will instead indicate via its exit status wether
201 matched any messages (`0') or not (`1');
202 note that messages are forcefully suppressed, then, and unless verbosity
203 is explicitly enabled (e.g., by using the
209 variable and thus inhibits the initial display of message headers when
210 reading mail or editing a mail folder.
212 Inhibits reading \*(UR upon startup.
213 This option should be activated for \*(UA scripts that are invoked on
214 more than one machine, because the contents of that file may differ
216 (The same behaviour can be achieved by setting the
217 .Ev NAIL_NO_SYSTEM_RC
218 environment variable.)
219 .It Fl O Ar mta-option
220 Pass the given option through to the mail-transfer-agent (MTA).
221 This option has no effect when mail is send via SMTP.
223 .Ns ` Ns Li "-O-h -Onumber" Ns '
224 to specify the hop count for an old
226 Options set like that persist for an entire (interactive) session.
228 Start the message with the contents of the specified file.
229 May be given in send mode only.
231 Opens any folders read-only.
233 Sets the envelope sender address by passing an
236 option to the MTA when a message is send.
239 argument is given it'll be checked for validity and then fixated to
240 the given value, but otherwise the content of the variable
242 will be used for that purpose \(en i.e., it'll be passed through to
245 option whenever a message is send.
246 A valid non-empty value will also be set as if an additional
247 .Ns ` Ns Li "-Sfrom=VALUE" Ns '
248 option had been used and therefore affect sending of messages via SMTP
249 (as a consideration for `From:').
250 .It Fl S Ar variable Ns Op = Ns value
251 Sets the internal option
253 and, in case of a value option, assigns
256 Even though options set via
258 may be overwritten from within resource files,
259 the command line setting will be reestablished after all resources have
262 Specify the subject on the command line
263 (be careful to quote subjects containing spaces).
265 The message to be sent is expected to contain a message header with
266 `To:', `Cc:', or `Bcc:' fields giving its recipients and `Subject:'
267 giving the subject of the message.
268 Recipients and subject specified on the command line are ignored.
270 Read the system mailbox of
272 (appropriate privileges presumed), and `assume to be'
274 in some aspects, e.g. in respect to expansions of `%' etc.
278 Print \*(UA's version and exit.
282 option causes some verbosity (like printing of certificate chains).
283 Using it twice increases the level of verbosity.
285 Enable tilde escapes even if not in interactive mode.
287 This sets multiple options to prepare \*(UA for working in batch mode
288 (most likely in non-interactive mode):
300 it also enables processing of tilde escapes.
301 E.g., the following should send an email message to `alias'.
303 .Dl printf 'm alias\en~s Subject\enBody\en.\enx\en' | \
304 MAILRC=/dev/null s-nail -n -#
308 .\" .Ss "Sending mail" {{{
310 To send a message to one or more people,
311 \*(UA can be invoked with arguments which are the names of people to
312 whom the mail will be sent.
315 es, plain addresses or full address specifications including user names
317 in which case care for proper quoting may be necessary.
318 If this manual refers to a \fIlist of addresses\fR,
319 then \*(UA expects a comma-separated list of such names.
321 .Sx "Recipient address specifications"
322 below explains the interpretation of names in more detail.
323 The user is then expected to type in his message, followed by a
325 at the beginning of a line.
327 .Sx "Replying to or originating mail"
328 describes some features of \*(UA available to help when composing
332 .\" .Ss "Reading mail" {{{
334 In normal usage \*(UA is given no arguments and checks the user's mail
335 out of the post office,
336 then prints out a one line header of each message found.
337 The current message is initially the first message (numbered 1) and can
340 command, which can be abbreviated `p'.
341 The commands `p+' and `p\-' move forward to the next and backward to the
342 previous message, respectively, and messages can be addressed directly
343 by specifying their message number, as in `p 1'.
346 .\" .Ss "Disposing of mail" {{{
347 .Ss "Disposing of mail"
348 After examining a message the user can
353 Deletion causes the \*(UA program to forget about the message.
354 This is not irreversible;
357 (`u') the message by giving its number,
358 or the \*(UA session can be ended by giving the
361 Deleted messages will, however, usually disappear never to be seen
365 .\" .Ss "Specifying messages" {{{
366 .Ss "Specifying messages"
367 Commands such as print and delete can be given a list of message numbers
368 as arguments to apply to a number of messages at once.
370 .Ns ` Ns Li "delete 1 2" Ns '
371 deletes messages 1 and 2,
373 .Ns ` Ns Li "delete 1-5" Ns '
374 will delete the messages 1 through 5.
375 In sorted or threaded mode (see the
380 .Ns ` Ns Li "delete 1-5" Ns '
381 will delete the messages that are located between (and including)
382 messages 1 through 5 in the sorted/threaded order, as shown in the
384 The following special message names exist:
386 .Bl -tag -width ".It .Ar :n:u"
390 All old messages (any not in state read or new).
394 All deleted messages (for the
400 All `flagged' messages.
402 All answered messages
407 All messages marked as draft.
409 \*(OP All messages classified as spam.
413 The message that was previously the current message.
415 The parent message of the current message,
416 that is the message with the Message-ID given in the `In-Reply-To:' field
417 or the last entry of the `References:' field of the current message.
419 The next previous undeleted message,
420 or the next previous deleted message for the
423 In sorted/threaded mode,
424 the next previous such message in the sorted/threaded order.
426 The next undeleted message,
427 or the next deleted message for the
430 In sorted/threaded mode,
431 the next such message in the sorted/threaded order.
433 The first undeleted message,
434 or the first deleted message for the
437 In sorted/threaded mode,
438 the first such message in the sorted/threaded order.
441 In sorted/threaded mode,
442 the last message in the sorted/threaded order.
445 selects the message addressed with
449 is any other message specification,
450 and all messages from the thread that begins at it.
451 Otherwise it is identical to
456 the thread beginning with the current message is selected.
460 All messages that were included in the message list for the previous
462 .It Ar / Ns Ar string
463 All messages that contain
465 in the subject field (case ignored).
472 the string from the previous specification of that type is used again.
473 .It Xo Op Ar @ Ns Ar name-list Ns
476 All messages that contain the given case-insensitive search
478 ession; if the \*(OPal regular expression (see
482 will be interpreted as one if any of the `magic'al regular expression
485 .Ar @ Ns Ar name-list
486 part is missing, the search is restricted to the subject field body,
489 specifies a comma-separated list of header fields to search, as in
491 .Dl '@to,from,cc@Someone i ought to know'
493 The special names `body' and `text' can be used to search in message
494 bodies \(en whereas the former searches only the body, the latter form
495 also performs a fulltext search in the header fields.
496 In order to search for a string that includes a `@' (commercial at)
499 is effectively non-optional, but may be given as the empty string.
503 By default, this is a case-sensitive search for the complete email
508 only the local part of the addresses is evaluated for the comparison.
512 a case-sensitive search for the complete real name of a sender is
515 .Ns ` Ns Li "(from address)" Ns '
516 expression can be used instead if substring matches are desired.
520 \*(OP IMAP-style SEARCH expressions may also be used.
521 This addressing mode is available with all types of folders;
522 for folders not located on IMAP servers,
523 or for servers unable to execute the SEARCH command,
524 \*(UA will perform the search locally.
525 Strings must be enclosed by double quotes `"' in their entirety
526 if they contain white space or parentheses;
528 only backslash `\e' is recognized as an escape character.
529 All string searches are case-insensitive.
530 When the description indicates that the `envelope' representation of an
531 address field is used,
532 this means that the search string is checked against both a list
535 .Dl ( \*q Ns name Ns \*q \*q Ns source Ns \*q \*q Ns \
536 local-part Ns \*q \*q Ns domain-part Ns \*q )
539 and the addresses without real names from the respective header field.
540 These search expressions can be nested using parentheses, see below for
542 .Bl -tag -width ".It .Ar :n:u"
544 All messages that satisfy the given
546 .It Ar ( criterion1 criterion2 ... criterionN )
547 All messages that satisfy all of the given criteria.
548 .It Ar ( or criterion1 criterion2 )
549 All messages that satisfy either
554 To connect more than two criteria using `or',
555 (or) specifications have to be nested using additional parentheses,
557 .Ns ` Ns Li "(or a (or b c))" Ns ',
559 .Ns ` Ns Li "(or a b c)" Ns '
561 .Ns ` Ns Li "((a or b) and c)" Ns '.
562 For a simple `or' operation of independent criteria on the lowest
564 it is possible to achieve similar effects by using three separate
566 .Ns ` Ns Li "(a) (b) (c)" Ns '.
567 .It Ar ( not criterion )
568 All messages that do not satisfy
570 .It Ar ( bcc \*q Ns Ar string Ns Ar \*q )
571 All messages that contain
573 in the `envelope' representation of the `Bcc:' field.
574 .It Ar ( cc \*q Ns Ar string Ns Ar \*q )
575 All messages that contain
577 in the `envelope' representation of the `Cc:' field.
578 .It Ar ( from \*q Ns Ar string Ns Ar \*q )
579 All messages that contain
581 in the `envelope' representation of the `From:' field.
582 .It Ar ( subject \*q Ns Ar string Ns Ar \*q )
583 All messages that contain
585 in the `Subject:' field.
586 .It Ar ( to \*q Ns Ar string Ns Ar \*q )
587 All messages that contain
589 in the `envelope' representation of the `To:' field.
590 .It Ar ( header name \*q Ns Ar string Ns Ar \*q )
591 All messages that contain
596 .It Ar ( body \*q Ns Ar string Ns Ar \*q )
597 All messages that contain
600 .It Ar ( text \*q Ns Ar string Ns Ar \*q )
601 All messages that contain
603 in their header or body.
604 .It Ar ( larger size )
605 All messages that are larger than
608 .It Ar ( smaller size )
609 All messages that are smaller than
612 .It Ar ( before date )
613 All messages that were received before
615 which must be in the form
616 .Li "d[d]-mon-yyyy" ,
617 where `d' denotes the day of the month as one or two digits,
618 `mon' is the name of the month \(en one of
619 `Jan', `Feb', `Mar', `Apr', `May', `Jun',
620 `Jul', `Aug', `Sep', `Oct', `Nov', or `Dec',
621 and `yyyy' is the year as four digits, e.g., "28-Dec-2012".
623 All messages that were received on the specified date.
624 .It Ar ( since date )
625 All messages that were received since the specified date.
626 .It Ar ( sentbefore date )
627 All messages that were sent on the specified date.
628 .It Ar ( senton date )
629 All messages that were sent on the specified date.
630 .It Ar ( sentsince date )
631 All messages that were sent since the specified date.
633 The same criterion as for the previous search.
634 This specification cannot be used as part of another criterion.
635 If the previous command line contained more than one independent
636 criterion then the last of those criteria is used.
640 .\" .Ss "Replying to or originating mail" {{{
641 .Ss "Replying to or originating mail"
644 can be used to set up a response to a message,
645 sending it back to the person who it was from.
646 Text the user types in, up to an end-of-file,
647 defines the contents of the message.
648 While the user is composing a message \*(UA treats lines beginning with
649 the character `~' specially.
650 For instance, typing `~m' (alone on a line) will place a copy of the
651 current message into the response, each line prefixed by the value of
653 Other escapes will set up subject fields,
654 add and delete recipients to the message,
656 and allow the user to escape to an editor to revise the message
657 or to a shell to run some commands.
658 (These options are given in the summary below.)
661 .\" .Ss "Ending a mail processing session" {{{
662 .Ss "Ending a mail processing session"
663 The user can end a \*(UA session by issuing the
666 Messages which have been examined go to the user's mbox file unless they
668 in which case they are discarded.
669 Unexamined messages go back to the post office.
673 When command line history is tracked, an updated history file is
675 None of these actions is performed when the command
677 (`x') is used instead of
682 .\" .Ss "Personal and systemwide distribution lists" {{{
683 .Ss "Personal and systemwide distribution lists"
684 It is possible to create personal distribution lists so that,
685 for instance, the user can send mail to `cohorts'
686 and have it go to a group of people.
687 Such lists can be defined via the
689 command by, e.g., placing lines like
691 .Dl alias cohorts bill ozalp jkf mark kridle@ucbcory
693 in the file \*(ur in the user's home directory.
696 without arguments lists all the currently known aliases.
698 Please note that this mechanism has nothing in common with the system
699 wide aliases that may be used by the local MTA (mail-transfer-agent)
700 and are often tracked in a file
707 Personal aliases will be expanded by \*(UA before the message is sent.
708 They are a convenient alternative to specifying each addressee by
712 .\" .Ss "Recipient address specifications" {{{
713 .Ss "Recipient address specifications"
714 When an address is used to name a recipient (in `To:', `Cc:', or `Bcc:'),
715 names of local mail folders and pipes to external commands may also be
716 specified \(en the message text is then written to them.
717 The rules are: Any name which starts with a `|' (vertical bar) character
718 specifies a pipe \(en the command string following the `|' is executed
719 and the message is sent to its standard input;
720 any other name which contains a `@' (at sign) character is treated as
722 any other name which starts with a `+' (plus sign) character specifies
724 any other name which contains a `/' (slash) character but no `!'
725 (exclamation mark) or `%' (percent sign) character before also specifies
727 what remains is treated as a mail address.
728 Compressed folders are handled as described for the
733 .\" .Ss "Network mail (Internet / ARPA, UUCP, Berknet)" {{{
734 .Ss "Network mail (Internet / ARPA, UUCP, Berknet)"
737 for a description of network addresses.
738 If support for IDNA (internationalized domain names for applications)
739 has been compiled into \*(UA,
740 then the domain name part of network addresses will be converted via
741 IDNA mechanisms as necessary, effectively treating it as a name in the
745 for the complete picture about character sets.
747 \*(UA has a number of options which can be set in the \*(ur file
748 to alter its behavior; e.g.,
753 .Ic "set idna-disable"
754 will disable the mentioned IDNA conversion even if support is available.
755 (These options are summarized below.)
758 .\" .Ss "MIME types" {{{
760 For any outgoing attachment \*(UA tries to determine the content type.
761 It does this by reading MIME type files whose lines have the following
764 .Dl type/subtype extension [extension ...]
766 where `type/subtype' are strings describing the file contents,
767 and `extension' is the part of a filename starting after the last dot.
768 Any line not immediately beginning with an ASCII alphabetical character
771 .Va mimetypes-load-control
772 can be used to control the sources of MIME types, and the
774 command can be used to show the list of mime types known to \*(UA.
775 If there is a match with the `extension' of the file to attach,
776 the given `type/subtype' pair is used.
777 Otherwise, or if the filename has no extension,
778 the content types `text/plain' or `application/octet-stream' are used,
779 dependent upon file content inspection.
781 .Va mime-allow-text-controls .
784 .\" .Ss "Character sets" {{{
786 \*(UA normally detects the character set of the terminal by using
787 mechanisms that are controlled by the `LC_CTYPE' locale setting,
788 if such are supported; the variable
790 will be set to the detected terminal character set and will thus
791 show up in the output of the command
796 value is not overwritten by this detection mechanism;
797 this feature must be used if the detection doesn't work properly,
798 and it may be used to adjust the name of the locale character set.
799 E.g., on BSD systems one may use a locale with the character set
800 `ISO8859-1', which is not a valid name for this character set;
801 to be on the safe side, one may set
803 to the correct name, `ISO-8859-1'.
805 Note that changing the value doesn't mean much beside that,
806 since several aspects of the real character set are implied by the
807 locale environment of the system,
808 and that stays unaffected by the content of an overwritten
811 (This is mostly an issue when interactively using \*(UA, though.
812 It is actually possible to send mail in a completely "faked" locale
815 If no character set conversion capabilities have been compiled into
818 library has been found), then
820 will be the only supported character set,
821 it is simply assumed that it can be used to exchange 8 bit messages,
822 and the rest of this section does not apply;
823 it may however still be necessary to explicitly set it if automatic
824 detection fails, since in that case it defaults to `ISO-8859-1'.
826 When reading messages, their text is converted into
828 as necessary in order to display them on the users terminal.
829 Unprintable characters and illegal byte sequences are detected
830 and replaced by proper substitution characters
833 was set once \*(UA was started).
835 When sending messages all their parts and attachments are classified.
836 Whereas no character set conversion is performed on those parts which
837 appear to be binary data,
838 the character set being used must be declared within the MIME header of
839 an outgoing text part if it contains characters that do not conform to
840 the set of characters that are allowed by the email standards.
841 Permissible values for character sets can be declared using the
845 which defines a catch-all last-resort fallback character set that is
846 implicitly appended to the list of character-sets in
849 All the specified character sets are tried in order unless the
850 conversion of the part or attachment succeeds.
851 If none of the tried (8 bit) character sets is capable to represent the
852 content of the part or attachment,
853 then the message will not be sent and its text will be saved to
855 In general, if the message `Cannot convert from a to b' appears, either
856 some characters are not appropriate for the currently selected
857 (terminal) character set,
858 or the needed conversion is not supported by the system.
859 In the first case, it is necessary to set an appropriate `LC_CTYPE'
860 locale and/or the variable
863 The best results are usually achieved when \*(UA is run in a UTF-8
864 locale on a UTF-8 capable terminal,
865 in which case the full Unicode spectrum of characters is available.
866 In this setup characters from various countries can be displayed,
867 while it is still possible to use more simple character sets for sending
868 to retain maximum compatibility with older mail clients.
871 .\" .Ss "Command line editor" {{{
872 .Ss "Command line editor"
873 \*(OP \*(UA can be configured to support a command line editor and
874 command history lists which are saved in between sessions.
875 One may link against fully-fledged external libraries
876 .Ns ( Ns Xr readline 3 ,
878 ) or use the \*(UA command line editor instead, which should work in all
879 environments which comply to ISO C (ISO/IEC 9899:1990/Amendment 1:1995).
880 When an external library is used, interactive behaviour of \*(UA relies
881 on that library and may not correspond one-to-one to what is described
884 Regardless of the actually used command line editor history entries
885 will be created for lines entered in command mode only, and creation of
886 such an entry can be forcefully suppressed by starting the line with
888 Note that history handling is by itself an optional feature and may
889 therefore not be available.
890 For more information see the documentation of the options
892 .Va line-editor-disable ,
897 The builtin \*(UA command line editor supports the following operations;
898 the notation `^-character' stands for the combination of the `control'
899 key plus the mentioned character, e.g., `^A' means "hold control key
900 while adding an A key on top of it":
901 .Bl -tag -width "^M^"
903 Go to the start of the line.
905 Move the cursor backward one character.
907 Forward delete the character under the cursor;
908 quits \*(UA if used on the empty line, unless the
912 Go to the end of the line.
914 Move the cursor forward one character.
916 Cancel current operation, full reset.
917 If there is an active history search or tabulator expansion then this
918 command will first reset that, reverting to the former line content;
919 thus a second reset is needed for a full reset in this case.
920 In all cases \*(UA will reset a possibly used multibyte character input
923 The same as `backspace': backward delete one character.
925 \*(OP The same as `horizontal tabulator': try to expand the "word"
927 Here "expansion" refers to the \*(UA expansion, as documented for
929 and thus includes shell word expansion (as a last step).
930 I.e., this is \*(UA "expansion", not what one usually expects from
933 The same as `ENTER': complete this line of input.
935 Delete all characters from the cursor to the end of the line.
939 \*(OP Go to the next history entry.
941 \*(OP Go to the previous history entry.
943 \*(OP Complete the current line from (the remaining older) history entries.
945 The same as `^A' followed by `^K'.
947 Delete the characters from the one preceding the cursor to the preceding
950 Move the cursor forward one word boundary.
952 Move the cursor backward one word boundary.
955 If problems with commands that are based upon rightwise movement are
956 encountered, adjustments of the option
957 .Va line-editor-cursor-right
958 may solve the problem, as documented for it.
960 If the terminal produces key sequences which are compatible with
962 then the left and right cursor keys will map to `^B' and `^F',
963 respectively, the up and down cursor keys will map to `^P' and `^N',
964 and the Home/End/PgUp/PgDown keys will call the
966 command with the respective arguments `0', `$', `-' and `+'
967 (i.e., perform scrolling through the header summary list).
970 .\" .Ss "Coloured message display" {{{
971 .Ss "Coloured message display"
972 \*(OP \*(UA can be configured to support coloured message display.
973 Colours are used only when the
975 environment variable is set and the terminal type can be found in
977 Beyond that, if a command requires to output through the
983 must be mentioned in the variable
985 otherwise no colours will be used regardless of the actual terminal type.
987 "Coloured message display" can be configured through font attributes
988 (`ft=' \(en `bold', `invers' and `underline'), foreground (`fg=') and
989 background (`bg=') colours (`black', `blue', `green', `red', `brown',
990 `magenta', `cyan' and `white').
991 Multiple specifications can be joined in a comma separated list, as in
993 .Dl set colour-msginfo="ft=bold,fg=magenta,bg=cyan"
995 Options to be set are
997 .Va colour-partinfo ,
1001 .Va colour-uheader ,
1003 .Va colour-user-headers ,
1004 which is a list of headers to be colourized via
1006 instead of the default
1008 To forcefully disable colours, set
1009 .Va colour-disable .
1012 .\" .Ss "Commands" {{{
1014 Each command is typed on a line by itself,
1015 and may take arguments following the command word.
1016 The command need not be typed in its entirety \(en
1017 the first command which matches the typed prefix is used.
1020 prints a sorted list of available commands, and the command
1022 when given an argument, will show a documentation string for the
1024 .Ns ` Ns Ic ? Ns Ar unc Ns ' ;
1025 documentation strings are however \*(OP.)
1027 For commands which take message lists as arguments,
1028 if no message list is given,
1029 then the next message forward which satisfies the command's requirements
1031 If there are no messages forward of the current message,
1032 the search proceeds backwards,
1033 and if there are no good messages at all,
1034 \*(UA types `no applicable messages' and aborts the command.
1035 If the command begins with a `#' (number sign) character,
1036 the line is ignored.
1038 The arguments to commands can be quoted, using the following methods:
1039 .Bl -bullet -offset indent
1041 An argument can be enclosed between paired double-quotes `"argument"' or
1042 single-quotes `'argument'';
1043 any white space, shell word expansion, or backslash characters (except
1044 as described next) within the quotes are treated literally as part of
1046 A double-quote will be treated literally within single-quotes and vice
1048 Inside such a quoted string the actually used quote character can be
1049 used nonetheless by escaping it with a backslash `\\', as in
1052 An argument that is not enclosed in quotes, as above, can usually still
1053 contain space characters if those spaces are backslash-escaped.
1055 A backslash outside of the enclosing quotes is discarded
1056 and the following character is treated literally as part of the argument.
1058 An unquoted backslash at the end of a command line is discarded and the
1059 next line continues the command.
1062 Filenames, where expected, are subsequently subjected to the following
1063 transformations, in sequence:
1064 .Bl -bullet -offset indent
1066 If the filename begins with an unquoted plus sign, and the
1068 variable is defined,
1069 the plus sign will be replaced by the value of the
1071 variable followed by a slash.
1074 variable is unset or is set to null, the filename will be unchanged.
1076 Shell word expansions are applied to the filename.
1077 If more than a single pathname results from this expansion and the
1078 command is expecting one file, an error results.
1082 The following commands are provided:
1083 .Bl -tag -width ".Ic account"
1085 Interprets the remainder of the word as a macro name and passes it
1089 .Ns ` Ns Ic ~ Ns Ar mymacro Ns '
1090 is a shorter synonym for
1091 .Ns ` Ns Ic call Ar mymacro Ns ' .
1093 Print out the preceding message.
1094 If given a numeric argument n,
1095 goes to the n'th previous message and prints it.
1097 Prints a brief summary of commands.
1098 \*(OP Given an argument a synopsis for the command in question is
1101 Executes the shell (see
1105 ) command which follows.
1111 (ac) Creates, selects or lists an email account.
1112 An account is formed by a group of commands,
1113 primarily of those to set variables.
1115 of which the second is a `{',
1116 the first argument gives an account name,
1117 and the following lines create a group of commands for that account
1118 until a line containing a single `}' appears.
1119 With one argument the previously created group of commands for the
1120 account name is executed, and a
1122 command is executed for the system mailbox or inbox of that account.
1123 Without arguments the list of accounts and their contents are printed.
1125 .Bd -literal -offset indent
1127 set folder=imaps://mylogin@imap.myisp.example
1129 set from="myname@myisp.example (My Name)"
1130 set smtp=smtp://mylogin@smtp.myisp.example
1134 creates an account named `myisp' which can later be selected by
1135 specifying `account myisp'.
1136 The special account `null' (case-insensitive) always exists.
1138 can be used to localize account settings.
1139 Accounts can be deleted via
1142 (a) With no arguments, prints out all currently-defined aliases.
1143 With one argument, prints out that alias.
1144 With more than one argument,
1145 creates a new alias or changes an old one.
1147 can be used to delete aliases.
1149 (alt) The alternates command is useful if the user has accounts on
1151 It can be used to inform \*(UA that the listed addresses all belong to
1153 When replying to messages \*(UA will not send a copy of the message
1154 to any of the addresses listed on the alternates list.
1155 If the alternates command is given with no argument,
1156 the current set of alternate names is displayed.
1158 (ans) Takes a message list and marks each message as having been
1160 This mark has no technical meaning in the mail system;
1161 it just causes messages to be marked in the header summary,
1162 and makes them specially addressable.
1164 \*(OP Only applicable to cached IMAP mailboxes;
1165 takes a message list and reads the specified messages into the IMAP
1168 Calls a macro (see the
1175 \*(OP Only applicable to S/MIME signed messages.
1176 Takes a message list and a file name and saves the certificates
1177 contained within the message signatures to the named file in both
1178 human-readable and PEM format.
1179 The certificates can later be used to send encrypted messages to the
1180 respective message senders by setting
1181 .Va smime-encrypt-USER@HOST
1184 (ch) Changes the user's working directory to the specified one,
1185 or to the user's login directory, if none was given.
1188 Only applicable to threaded mode.
1189 Takes a message list and makes all replies to these messages invisible
1190 in header summaries,
1191 unless they are in state `new'.
1193 \*(OP (conn) If operating in disconnected mode on an IMAP mailbox,
1194 switch to online mode and connect to the mail server while retaining the
1196 See the description of the
1198 variable for more information.
1200 (c) The copy command does the same thing that
1202 does except that it does not mark the given messages for deletion when
1204 Compressed files and IMAP mailboxes are handled as described for the
1210 but saves the messages in a file named after the local part of the
1211 sender address of the first message.
1213 Print the current working directory.
1215 \*(OP (dec) For unencrypted messages,
1216 this command is identical to
1218 Encrypted messages are first decrypted, if possible, and then copied.
1220 \*OP (Dec) Similar to
1222 but saves the messages in a file named after the local part of the
1223 sender address of the first message.
1225 (def) Without arguments the current list of macros, including their
1226 content, is printed.
1227 If arguments are given this command defines a macro.
1228 A macro definition is a sequence of commands in the following form:
1229 .Bd -literal -offset indent
1238 A defined macro can be explicitly invoked using
1242 or it can be implicitly invoked by setting the
1245 .Va folder-hook-fullname
1247 Macros can be deleted via
1250 (d) Takes a list of messages as argument and marks them all as deleted.
1251 Deleted messages will not be saved in `mbox',
1252 nor will they be available for most other commands.
1257 \*(OP (disco) If operating in online mode on an IMAP mailbox,
1258 switch to disconnected mode while retaining the mailbox status.
1259 See the description of the
1262 A list of messages may optionally be given as argument;
1263 the respective messages are then read into the cache before the
1264 connection is closed.
1265 Thus `disco *' makes the entire mailbox available for disconnected use.
1266 .It Ic dp Ns \ or Ic dt
1267 Deletes the current message and prints the next message.
1268 If there is no next message, \*(UA says `at EOF'.
1270 Takes a message list and marks each given message as a draft.
1271 This mark has no technical meaning in the mail system;
1272 it just causes messages to be marked in the header summary,
1273 and makes them specially addressable.
1275 Echoes its arguments,
1276 resolving special names as documented for the command
1278 The escape sequences `\ea', `\eb', `\ec', `\ef', `\en', `\er', `\et',
1279 `\ev', `\e\e', and `\e0octal-num\fR' are interpreted just as they are by
1281 (proper quoting provided).
1283 (e) Point the text editor at each message from the given list in turn.
1284 Modified contents are discarded unless the
1293 conditional \(em if the condition of a preceeding
1295 was false, check the following condition and execute the following block
1296 if it evaluates true.
1303 conditional \(em if none of the conditions of the preceeding
1307 commands was true, the
1316 conditional execution block.
1318 (ex or x) Effects an immediate return to the Shell without modifying the
1319 user's system mailbox, his `mbox' file, or his edit file in
1321 as well as a possibly tracked command line editor history file.
1323 Print the list of features that have been compiled into \*(UA.
1328 (fl) Takes a message list and marks the messages as `flagged' for
1329 urgent/special attention.
1330 This mark has no technical meaning in the mail system;
1331 it just causes messages to be highlighted in the header summary,
1332 and makes them specially addressable.
1334 (fold) The folder command switches to a new mail file or folder.
1335 With no arguments, it tells the user which file he is currently reading.
1336 If an argument is given, it will write out changes (such as deletions)
1337 the user has made in the current file and read in the new file.
1338 Some special conventions are recognized for the
1341 .Bl -tag -offset indent -width ".Ar %:filespec"
1343 (number sign) means the previous file,
1345 (percent sign) means the invoking user's system mailbox
1350 means the system mailbox of `user'
1351 (and never the value of
1353 regardless of its actual setting),
1355 (ampersand) means the invoking user's `mbox' file (see
1359 means a `file' in the
1363 expands to the same value as `filespec',
1364 but the file is handled as a system mailbox by, e.g., the
1371 If the name matches one of the strings defined with the command
1373 it is replaced by its long form and expanded.
1374 If the name ends with `.gz', `.bz2' or `.xz' it is treated as being
1381 If `name' refers to a directory with the subdirectories `tmp', `new',
1382 and `cur', then it is treated as a folder in `maildir' format.
1385 .Dl \*(IN protocol://[user[:password]@]host[:port][/path]
1386 .Dl \*(OU protocol://[user@]host[:port][/path]
1388 is taken as an Internet mailbox specification.
1389 The \*(OPally supported protocols are `imap' (IMAP v4r1), `imaps'
1390 (IMAP with SSL/TLS encrypted transport), `pop3' (POP3) and `pop3s' (POP3
1391 with SSL/TLS encrypted transport).
1392 The `[/path]' part is valid only for IMAP; there it defaults to `INBOX'.
1394 \*(IN If `user' or `password' contain special characters, in particular
1395 whitespace, `/', `:' or `%', they must be specified in URL notation
1398 may be helpful for preparation).
1399 If no `user' is specified in the URL, the
1401 variable chain is inspected; likewise the
1403 variable chain for the password.
1405 \*(OU If `user' contains special characters, in particular `/' or `%',
1406 they must be escaped in URL notation \(en the command
1408 can be used to show the necessary conversion.
1409 The optional `path' part applies to IMAP only;
1410 if it is omitted, the default `INBOX' is used.
1412 If \*(UA is connected to an IMAP server,
1413 a name of the form `@mailbox' refers to the `mailbox' on that server,
1414 but otherwise a `@' prefix has no special meaning.
1416 With no arguments, list the names of the folders in the folder directory.
1417 With an existing folder as an argument,
1418 lists the names of folders below the named folder;
1419 e.\|g. the command `folders @' lists the folders on the base level of
1420 the current IMAP server.
1421 See also the variable
1422 .Va imap-list-depth .
1426 but saves the message in a file named after the local part of the first
1427 recipient's address.
1431 but saves the message in a file named after the local part of the first
1432 recipient's address.
1436 but responds to all recipients regardless of the
1441 .It Ic followupsender
1444 but responds to the sender only regardless of the
1450 (fwd) Takes a message and the address of a recipient
1451 and forwards the message to him.
1452 The text of the original message is included in the new one,
1453 with the value of the
1455 variable printed before.
1460 commands specify which header fields are included in the new message.
1461 Only the first part of a multipart message is included unless the
1462 .Va forward-as-attachment
1467 but saves the message in a file named after the local part of the
1468 recipient's address.
1470 (f) Takes a list of messages and prints their message headers,
1471 piped through the pager if the output does not fit on the screen.
1473 Specifies which header fields are to be ignored with the command
1475 This command has no effect when the
1476 .Va forward-as-attachment
1479 Specifies which header fields are to be retained with the command
1484 This command has no effect when the
1485 .Va forward-as-attachment
1488 Without arguments it lists all currently defined command aliases,
1490 With two arguments it defines a new command alias: the first argument is
1491 the name under which the second should be accessible.
1492 The content of the second argument can be just about anything.
1493 A ghost can be used everywhere a normal command can be used, but always
1494 takes precedence; any arguments that are given to the command alias are
1495 joined onto the alias content, and the resulting string forms the
1496 command line that is, in effect, executed.
1500 .Dl ? ghost ls '!ls -latro'
1503 (h) Lists the current range of headers, which is an 18-message group.
1504 If a `+' argument is given the next 18-message group is printed,
1505 likewise the previous is printed if the argument was `-'.
1513 the list of history entries;
1516 argument selects and shows the respective history entry \(en
1517 press `ENTER' to accept it, and the history entry will become the new
1519 The default mode if no arguments are given is
1522 (ho, also preserve) Takes a message list and marks each message therein
1523 to be saved in the user's system mailbox instead of in `mbox'.
1524 Does not override the
1527 \*(UA deviates from the POSIX standard with this command,
1530 command issued after
1532 will display the following message, not the current one.
1534 Part of the nestable
1539 conditional execution construct \(em if the given condition is false
1540 execute the following block.
1541 .Bd -literal -offset indent
1549 Note that POSIX only supports the conditions `[Rr]eceive', `[Ss]end'
1550 and `[Tt]erm' (execute if standard input is a tty).
1551 Extensions are `0' (never execute) and `1' (always execute);
1552 it is also possible to conditionalize upon wether an option is set,
1553 or set to a specific value, by using the `$' conditional trigger, e.g.:
1554 .Bd -literal -offset indent
1558 if $encoding == "UTF-8"
1561 if $encoding != "UTF-8"
1566 The first form simply checks wether an option is set, the other two also
1567 perform value content comparison (equality and non-equality,
1568 respectively); an unset value is treated as the empty string, then.
1569 The \*(OPal regular expression support adds `=~' and `!~' tests, which
1570 treat the right hand side as a regular expression, e.g., `^UTF.*' (see
1574 Add the list of header fields named to the ignored list.
1575 Header fields in the ignore list are not printed on the terminal when
1576 a message is printed.
1577 This command is very handy for suppression of certain machine-generated
1583 commands can be used to print a message in its entirety, including
1585 It lists the current set of ignored fields if no arguments were given.
1587 \*(OP Sends command strings directly to the current IMAP server.
1588 \*(UA operates always in IMAP `selected state' on the current mailbox;
1589 commands that change this will produce undesirable results and should be
1591 Useful IMAP commands are:
1592 .Bl -tag -offset indent -width ".Ic getquotearoot"
1594 Takes the name of an IMAP mailbox as an argument and creates it.
1596 (RFC 2087) Takes the name of an IMAP mailbox as an argument
1597 and prints the quotas that apply to the mailbox.
1598 Not all IMAP servers support this command.
1600 (RFC 2342) Takes no arguments and prints the Personal Namespaces,
1601 the Other User's Namespaces and the Shared Namespaces.
1602 Each namespace type is printed in parentheses;
1603 if there are multiple namespaces of the same type,
1604 inner parentheses separate them.
1605 For each namespace a prefix and a hierarchy separator is listed.
1606 Not all IMAP servers support this command.
1612 Prints the names of all available commands, alphabetically sorted.
1614 Can only be used inside of a macro definition block introduced by
1618 and is interpreted as a boolean (value `0' means false, everything
1620 Any option that had been set while `localopts' was in effect will be
1621 reverted to its former value once the block is left / the `account'
1623 .Bd -literal -offset indent
1624 define temporary_settings {
1634 Note that these options stack upon each other, i.e., if macro1 sets
1635 `localopts' and calls macro2, which explicitly resets `localopts', then
1636 any values set within macro2 will still be cleaned up by macro1.
1640 but saves the message in a file named after the local part of the first
1641 recipient's address.
1643 (m) Takes a (list of) recipient address(es) as (an) argument(s),
1644 or asks on standard input if none were given;
1645 then collects the remaining mail content and sends it out.
1647 The given message list is to be sent to `mbox' when \*(UA is quit.
1648 This is the default action unless the
1651 \*(UA deviates from the POSIX standard with this command,
1654 command issued after
1656 will display the following message, not the current one.
1665 In the former case all sources are loaded first as necessary.
1667 .Va mimetypes-load-control
1668 option can be used to fine-tune which sources are loaded.
1672 but marks the messages for deletion if they were transferred
1675 Takes a message list and invokes the
1677 on that list, printing a form-feed (`\\f') in between messages.
1681 but also prints ignored header fields and all MIME parts.
1685 but moves the messages to a file named after the local part of the
1686 sender address of the first message.
1688 Checks for new mail in the current folder without committing any changes
1690 If new mail is present, a message is printed.
1694 the headers of each new message are also printed.
1696 (n) (like `+' or `ENTER') Goes to the next message in sequence
1698 With an argument list, types the next matching message.
1709 If the current folder is located on an IMAP or POP3 server,
1710 a `NOOP' command is sent.
1711 Otherwise, no operation is performed.
1715 but also pipes ignored header fields and all parts of MIME
1716 `multipart/alternative' messages.
1718 (pi) Takes a message list and a shell command
1719 and pipes the messages through the command.
1720 Without an argument the current message is piped through the command
1727 every message is followed by a formfeed character.
1734 but also prints out ignored header fields and all parts of MIME
1735 `multipart/alternative' messages.
1742 (p) Takes a message list and types out each message on the user's
1744 If the message is a MIME multipart message,
1745 all parts with a content type of `text' or `message' are shown,
1746 the other are hidden except for their headers.
1747 Messages are decrypted and converted to the terminal character set
1750 (q) Terminates the session, saving all undeleted, unsaved messages in
1751 the current `mbox', preserving all messages marked with
1755 or never referenced in his system mailbox,
1756 and removing all other messages from his system mailbox.
1757 If new mail has arrived during the session,
1758 the message `You have new mail' is given.
1759 If given while editing a mailbox file with the command line flag
1761 then the edit file is rewritten.
1762 A return to the shell is effected,
1763 unless the rewrite of edit file fails,
1764 in which case the user can escape with the exit command.
1772 (rem) Removes the named folders.
1773 The user is asked for confirmation in interactive mode.
1775 (ren) Takes the name of an existing folder
1776 and the name for the new folder
1777 and renames the first to the second one.
1778 Both folders must be of the same type
1779 and must be located on the current server for IMAP.
1781 (R) Reply to originator.
1782 Does not reply to other recipients of the original message.
1784 (r) Takes a message list and sends mail to the sender and all recipients
1785 of the specified messages.
1786 The default message must not be deleted.
1790 but responds to all recipients regardless of the
1798 but responds to the sender only regardless of the
1806 but does not add any header lines.
1807 This is not a way to hide the sender's identity,
1808 but useful for sending a message again to the same recipients.
1810 Takes a list of messages and a user name
1811 and sends each message to the named user.
1812 `Resent-From:' and related header fields are prepended to the new copy
1823 .It Ic respondsender
1827 Add the list of header fields named to the retained list.
1828 Only the header fields in the retain list are shown on the terminal when
1829 a message is printed, all other header fields are suppressed.
1834 commands can be used to print a message in its entirety.
1835 The current set of retained fields is shown if
1837 is used without arguments.
1841 but saves the messages in a file named after the local part of the
1842 sender of the first message instead of taking a filename argument.
1844 (s) Takes a message list and a filename and appends each message in turn
1845 to the end of the file.
1846 If no filename is given, the `mbox' file is used.
1847 The filename in quotes, followed by the line count and character count
1848 is echoed on the user's terminal.
1849 If editing a system mailbox the messages are marked for deletion.
1850 Compressed files and IMAP mailboxes are handled as described for the
1852 command line option above.
1865 Header fields thus marked are filtered out when saving a message by
1867 or when automatically saving to `mbox'.
1868 This command should only be applied to header fields that do not contain
1869 information needed to decode the message,
1870 as MIME content fields do.
1871 If saving messages on an IMAP account ignoring fields makes it
1872 impossible to copy the data directly on the server,
1873 thus operation usually becomes much slower.
1883 Header fields thus marked are the only ones saved with a message when
1886 or when automatically saving to `mbox'.
1890 The use of this command is strongly discouraged since it may strip
1891 header fields that are needed to decode the message correctly.
1893 Takes a message list and marks all messages as having been read.
1895 (se) With no arguments, prints all variable values.
1896 Otherwise, sets an option.
1897 Arguments are of the form `option=value' (no space before or after `='),
1898 or plain `option' if there is no value.
1899 Quotation marks may be placed around any part of the assignment
1900 statement to quote blanks or tabs, e.g.,
1902 .Dl set indentprefix="->"
1904 If an argument begins with `no', as in `set nosave',
1905 the effect is the same as invoking the
1907 command with the remaining part of the variable (`unset save').
1911 except that the options are also exported into the program environment;
1912 since this task requires native host support the command will always
1913 report error if that is not available (but still act like
1916 This operation is a no-op unless all resource files have been loaded.
1920 (sh) Invokes an interactive version of the shell.
1922 Defines a shortcut name and its string for expansion,
1923 as described for the
1926 If used without arguments the currently defined shortcuts are printed.
1930 but performs neither MIME decoding nor decryption so that the raw
1931 message text is shown.
1933 Print the size in characters of each message of the given message-list.
1935 Create a sorted representation of the current folder,
1938 command and the addressing modes such that they refer to messages in the
1940 Message numbers are the same as in regular mode.
1944 a header summary in the new order is also printed.
1945 Possible sorting criteria are:
1946 .Bl -tag -offset indent -width "subject"
1948 Sort the messages by their `Date:' field,
1949 that is by the time they were sent.
1951 Sort messages by the value of their `From:' field,
1952 that is by the address of the sender.
1956 the sender's real name (if any) is used.
1958 Sort the messages by their size.
1960 \*(OP Sort the message by their spam score, as has been classified via
1964 Sort the messages by their message status (new, read, old, etc.).
1966 Sort the messages by their subject.
1968 Create a threaded order,
1972 Sort messages by the value of their `To:' field,
1973 that is by the address of the recipient.
1977 the recipient's real name (if any) is used.
1980 If no argument is given,
1981 the current sorting criterion is printed.
1983 The source command reads commands from a file.
1985 \*(OP Takes a list of messages and clears their `is-spam' flag.
1987 \*(OP Takes a list of messages and forces the spam detector to forget it
1988 has ever used them to train its Bayesian filter, wether as `ham' or
1991 \*(OP Takes a list of messages and teaches them to the spam detector as
1993 This also clears the `is-spam' flag of the messages in question.
1995 \*(OP Takes a list of messages and rates them using the configured spam
1996 detector, setting their `is-spam' flag as appropriate.
1997 Note that the messages are not modified, and due to that the rating will
1998 get lost once the mailbox is left.
1999 Refer to the manual section
2001 for the complete picture of spam handling in \*(UA.
2003 \*(OP Takes a list of messages and sets their `is-spam' flag.
2005 \*(OP Takes a list of messages and teaches them to the spam detector as
2007 This also sets the `is-spam' flag of the messages in question.
2009 (th) Create a threaded representation of the current folder,
2010 i.\|e. indent messages that are replies to other messages in the header
2011 display and change the
2013 command and the addressing modes such that they refer to messages in the
2015 Message numbers are the same as in unthreaded mode.
2019 a header summary in threaded order is also printed.
2021 Takes a message list and prints the top few lines of each.
2022 The number of lines printed is controlled by the variable
2024 and defaults to five.
2026 Takes a message list and marks the messages for saving in `mbox'.
2027 \*(UA deviates from the POSIX standard with this command,
2030 command issued after `mbox' will display the following message instead
2033 (T) Identical to the
2040 Delete all given accounts.
2041 An error message is printed if a given account is not defined.
2042 Attempts to delete the currently active account are rejected.
2044 Takes a list of names defined by alias commands
2045 and discards the remembered groups of users.
2047 Takes a message list and marks each message as not having been answered.
2049 (unc) Only applicable to threaded mode.
2050 Takes a message list and makes the message and all replies to it visible
2051 in header summaries again.
2052 When a message becomes the current message,
2053 it is automatically made visible.
2054 Also when a message with collapsed replies is printed,
2055 all of these are automatically uncollapsed.
2057 Undefine all given macros.
2058 An error message is printed if a given macro is not defined.
2060 (u) Takes a message list and marks each message as not being deleted.
2062 Takes a message list and
2063 .Ns un Ns Ic draft Ns
2066 Takes a message list and marks each message as not being
2069 Removes the header field names from the list of ignored fields for the
2073 Removes the header field names from the list of retained fields for the
2077 Remove an existing command
2080 Removes the header field names from the list of ignored fields.
2085 (U) Takes a message list and marks each message as not having been read.
2087 Removes the header field names from the list of retained fields.
2089 Removes the header field names from the list of ignored fields for
2092 Removes the header field names from the list of retained fields for
2095 Takes a list of option names and discards their remembered values;
2101 except that the options are also removed from the program environment;
2102 since this task requires native host support the command will always
2103 report error if that is not available (but still act like
2106 This operation is a no-op unless all resource files have been loaded.
2110 Deletes the shortcut names given as arguments.
2112 Disable sorted or threaded mode
2118 return to normal message order and,
2122 print a header summary.
2127 Decode the given URL-encoded string arguments and show the results.
2129 URL-encode the given arguments and show the results.
2131 Show information about all given options.
2133 \*(OP (verif) Takes a message list and verifies each message.
2134 If a message is not an S/MIME signed message,
2135 verification will fail for it.
2136 The verification process checks if the message was signed using a valid
2138 if the message sender's email address matches one of those contained
2139 within the certificate,
2140 and if the message content has been altered.
2142 (v) Takes a message list and invokes the display editor on each message.
2143 Modified contents are discarded unless the
2147 (w) For conventional messages the body without all headers is written.
2148 The output is decrypted and converted to its native format as necessary.
2149 If the output file exists, the text is appended.
2150 If a message is in MIME multipart format its first part is written to
2151 the specified file as for conventional messages,
2152 and the user is asked for a filename to save each other part.
2153 For convience saving of each part may be skipped by giving an empty value;
2154 the same result can also be achieved by writing it to
2156 For the second and subsequent parts a leading `|' character causes the
2157 part to be piped to the remainder of the user input interpreted as
2159 otherwise the user input is expanded as usually for folders,
2160 e.g., tilde expansion is performed.
2161 In non-interactive mode, only the parts of the multipart message
2162 that have a filename given in the part header are written,
2163 the others are discarded.
2164 The original message is never marked for deletion in the originating
2167 the contents of the destination file are overwritten if the file
2169 No special handling of compressed files is performed.
2174 \*(UA presents message headers in windowfuls as described under the
2177 This command scrolls to the next window of messages.
2178 If an argument is given,
2179 it specifies the window to use.
2180 A number prefixed by `+' or `\-' indicates
2181 that the window is calculated in relation to the current position.
2182 A number without a prefix specifies an absolute window number,
2183 and a `$' lets \*(UA scroll to the last window of messages.
2187 but scrolls to the next or previous window that contains at least one
2188 new or `flagged' message.
2192 .\" .Ss "Tilde escapes" {{{
2194 Here is a summary of the tilde escapes,
2195 which are used to perform special functions when composing messages.
2196 Tilde escapes are only recognized at the beginning of lines.
2197 The name `tilde escape' is somewhat of a misnomer since the actual
2198 escape character can be set by the option
2200 .Bl -tag -width ".Ic ~< filename"
2202 Insert the string of text in the message prefaced by a single `~'.
2203 (If the escape character has been changed,
2204 that character must be doubled
2205 in order to send it at the beginning of a line.)
2206 .It Ic ~! Ar command
2207 Execute the indicated shell
2209 then return to the message.
2211 Same effect as typing the end-of-file character.
2212 .It Ic ~: Ar \*(UA-command Ns \ or Ic ~_ Ar \*(UA-command
2213 Execute the given \*(UA command.
2214 Not all commands, however, are allowed.
2216 Write a summary of command escapes.
2217 .It Ic ~< Ar filename
2220 .It Ic ~<! Ar command
2222 is executed using the shell.
2223 Its standard output is inserted into the message.
2224 .It Ic ~@ Op Ar filename...
2225 With no arguments, edit the attachment list interactively.
2226 If an attachment's file name is left empty,
2227 that attachment is deleted from the list.
2228 When the end of the attachment list is reached,
2229 \*(UA will ask for further attachments until an empty name is given.
2230 If a given file name solely consists of the number sign `#' followed
2231 by a valid message number of the currently active mailbox, the given
2232 message is attached as a MIME `message/rfc822' and the rest of this
2233 section does not apply.
2235 If character set conversion has been compiled into \*(UA, then this mode
2236 gives the user the option to specify input and output character sets,
2237 unless the file extension indicates binary content, in which case \*(UA
2238 asks wether this step shall be skipped for the attachment in question.
2239 If not skipped, then the charset that succeeds to represent the
2240 attachment data will be used in the `charset=' MIME parameter of the
2244 If input and output character sets are specified, then the conversion is
2245 performed on the fly.
2246 The user will be asked repeatedly until the desired conversion succeeds.
2248 If only an output character set is specified, then the input is assumed
2251 charset and will be converted to the given output charset on the fly.
2252 The user will be asked repeatedly until the desired conversion succeeds.
2254 If no character sets are specified at all then the algorithm that is
2255 documented in the section
2256 .Sx "Character sets"
2257 is applied, but directly and on the fly.
2258 The user will be asked repeatedly until the desired conversion succeeds.
2260 Finally, if an input-, but no output character set is specified, then no
2261 conversion is ever performed, but the `charset=' MIME parameter will
2262 still be set to the user input.
2264 The character set selection loop can be left by typing `control-C',
2265 i.e., causing an interrupt.
2266 .\" \*(OU next sentence
2267 Note that before \*(UA version 15.0 this terminates the entire
2268 current attachment selection, not only the character set selection.
2271 Without character set conversion support, \*(UA will ask for the input
2272 character set only, and it'll set the `charset=' MIME parameter to the
2273 given input, if any;
2274 if no user input is seen then the
2276 character set will be used for the `charset=' parameter instead.
2277 Note that the file extension check isn't performed in this mode, since
2278 no conversion will take place anyway.
2280 Note that in non-interactive mode, for reproduceabilities sake, there
2281 will always be two questions for each attachment, regardless of wether
2282 character set conversion is available and what the file extension is.
2283 The first asks for the filename, and the second asks for the input
2284 character set to be passed through to the `charset=' MIME parameter;
2285 no conversion will be tried if there is input to the latter question,
2286 otherwise the usual conversion algorithm, as above, is applied.
2287 For message attachments, the answer to the second question is completely
2292 arguments are specified,
2293 they are treated as a comma separated list of files,
2294 which are all expanded and appended to the end of the attachment list.
2295 (Filenames with commas, or with leading or trailing whitespace can only
2296 be added via the command line or the first method.
2297 Message attachments can only be added via the first method;
2298 filenames which clash with message numbers can only be added via the
2299 command line or the second method.)
2300 In this mode the (text) attachments are assumed to be in
2302 encoding, and will be evaluated as documented in the section
2303 .Sx "Character sets" .
2305 Inserts the string contained in the
2307 variable (same as `~i Sign').
2308 The escape sequences `\et' (tabulator) and `\en' (newline) are understood.
2310 Inserts the string contained in the
2312 variable (same as `~i sign').
2313 The escape sequences `\et' (tabulator) and `\en' (newline) are understood.
2314 .It Ic ~b Ar name ...
2315 Add the given names to the list of blind carbon copy recipients.
2316 .It Ic ~c Ar name ...
2317 Add the given names to the list of carbon copy recipients.
2319 Read the file specified by the
2321 variable into the message.
2323 Invoke the text editor on the message collected so far.
2324 After the editing session is finished,
2325 the user may continue appending text to the message.
2326 .It Ic ~F Ar messages
2327 Read the named messages into the message being sent, including all
2328 message headers and MIME parts.
2329 If no messages are specified, read in the current message.
2330 .It Ic ~f Ar messages
2331 Read the named messages into the message being sent.
2332 If no messages are specified, read in the current message.
2333 Message headers currently being ignored (by the
2337 command) are not included.
2338 For MIME multipart messages,
2339 only the first printable part is included.
2341 Edit the message header fields `From:', `Reply-To:', `Sender:' and
2342 `Organization:' by typing each one in turn and allowing the user to edit
2344 The default values for these fields originate from the
2352 Edit the message header fields `To:', `Cc:', `Bcc:', and `Subject:' by
2353 typing each one in turn and allowing the user to edit the field.
2354 .It Ic ~i Ar variable
2355 Insert the value of the specified variable into the message,
2356 adding a newline character at the end.
2357 The message remains unaltered if the variable is unset or empty.
2358 The escape sequences `\et' (tabulator) and `\en' (newline) are understood.
2359 .It Ic ~M Ar messages
2360 Read the named messages into the message being sent,
2363 If no messages are specified, read the current message.
2364 .It Ic ~m Ar messages
2365 Read the named messages into the message being sent,
2368 If no messages are specified, read the current message.
2369 Message headers currently being ignored (by the
2373 commands) are not included.
2374 For MIME multipart messages,
2375 only the first printable part is included.
2377 Print out the message collected so far,
2378 prefaced by the message header fields
2379 and followed by the attachment list, if any.
2381 Abort the message being sent,
2382 copying it to the file specified by the
2387 .It Ic ~R Ar filename
2388 Read the named file into the message, indented by
2390 .It Ic ~r Ar filename
2391 Read the named file into the message.
2393 Cause the named string to become the current subject field.
2394 .It Ic ~t Ar name ...
2395 Add the given name(s) to the direct recipient list.
2396 .It Ic ~U Ar messages
2397 Like `~m', but exclude all message headers.
2398 .It Ic ~u Ar messages
2399 Like `~f', but exclude all message headers.
2401 Invoke an alternate editor (defined by the
2403 option) on the message collected so far.
2404 Usually, the alternate editor will be a screen editor.
2405 After the editor is quit,
2406 the user may resume appending text to the end of the message.
2407 .It Ic ~w Ar filename
2408 Write the message onto the named file.
2410 the message is appended to it.
2412 Same as `~q', except that the message is not saved at all.
2413 .It Ic ~| Ar command
2414 Pipe the message through the specified filter command.
2415 If the command gives no output or terminates abnormally,
2416 retain the original text of the message.
2419 is often used as a rejustifying filter.
2423 .\" .Ss "Variable options" {{{
2424 .Ss "Variable options"
2425 Options are controlled via
2429 commands, see the corresponding entries for a syntax description.
2430 An option is also set if it is passed to \*(UA as part of the program
2431 environment (this is not restricted to specific variables as in the
2433 A value given in a startup file overrides a value imported from the
2435 Options may be either binary, in which case it is only significant to
2436 see whether they are set or not;
2437 or string, in which case the actual value is of interest.
2440 .\" .Ss "Binary options" {{{
2441 .Ss "Binary options"
2442 The binary options include the following:
2443 .Bl -tag -width ".Va autoprint"
2444 .It Va add-file-recipients
2445 When file or pipe recipients have been specified,
2446 mention them in the corresponding address fields of the message instead
2447 of silently stripping them from their recipient list.
2448 By default such addressees are not mentioned.
2450 Causes only the local part to be evaluated
2451 when comparing addresses.
2453 Causes messages saved in mbox to be appended to the end rather than
2455 This should always be set.
2456 .It Va ask Ns \ or Va asksub
2457 Causes \*(UA to prompt for the subject of each message sent.
2458 If the user responds with simply a newline,
2459 no subject field will be sent.
2461 Causes the prompts for `Cc:' and `Bcc:' lists to appear after the
2462 message has been edited.
2464 If set, \*(UA asks for files to attach at the end of each message.
2465 An empty line finalizes the list.
2467 Causes the user to be prompted for additional carbon copy recipients (at
2468 the end of each message if
2473 An empty line finalizes the list.
2475 Causes the user to be prompted for additional blind carbon copy
2476 recipients (at the end of each message if
2481 An empty line finalizes the list.
2483 \*(OP Causes the user to be prompted if the message is to be signed at
2484 the end of each message.
2487 variable is ignored when this variable is set.
2489 Causes threads to be collapsed automatically when threaded mode is
2494 Causes the delete command to behave like `dp -';
2495 thus, after deleting a message the next one will be typed automatically.
2497 Causes threaded mode (see the
2499 command) to be entered automatically when a folder is opened.
2501 Enables the substitution of `!' by the contents of the last command line
2503 .It Va batch-exit-on-error
2504 If the batch mode has been enabled via the
2506 command line option, then this variable will be consulted whenever \*(UA
2507 completes one operation (returns to the command prompt); if it is set
2508 then \*(UA will terminate if the last operation generated an error.
2510 Causes automatic display of a header summary after executing a
2514 Sets some cosmetical features to traditional BSD style;
2515 has the same affect as setting
2517 and all other variables prefixed with `bsd';
2518 it also changes the meaning of the \*(UA specific `\\&'
2522 Changes the letters printed in the first column of a header summary
2523 to traditional BSD style.
2525 Changes the display of columns in a header summary to traditional BSD
2528 Changes some informational messages to traditional BSD style.
2530 Causes the `Subject:' field to appear immediately after the `To:' field
2531 in message headers and with the `~h' tilde command.
2533 Changes the output format of the
2535 command to traditional BSD style.
2536 .It Va colour-disable
2537 \*(OP Forcefully disable usage of colours.
2538 Also see the section
2539 .Sx "Coloured message display" .
2541 Prints debugging messages and disables the actual delivery of messages.
2544 this option is intended for \*(UA development only.
2546 \*(OP When an IMAP mailbox is selected and this variable is set,
2547 no connection to the server is initiated.
2548 Instead, data is obtained from the local cache (see
2551 Mailboxes that are not present in the cache
2552 and messages that have not yet entirely been fetched from the server
2554 to fetch all messages in a mailbox at once,
2556 .Ns ` Ns Li copy * /dev/null Ns '
2557 can be used while still in
2560 Changes that are made to IMAP mailboxes in disconnected mode are queued
2561 and committed later when a connection to that server is opened in online
2563 This procedure is not completely reliable since it cannot be guaranteed
2564 that the IMAP unique identifiers (UIDs) on the server still match the
2565 ones in the cache at that time.
2568 when this problem occurs.
2569 .It Va disconnected-USER@HOST
2570 The specified account is handled as described for the
2573 but other accounts are not affected.
2575 The binary option dot causes \*(UA to interpret a period alone on a line
2576 as the terminator of a message the user is sending.
2578 If this variable is set then the editor is started automatically when
2579 composing a message in an interactive mode,
2580 as if the `~e' tilde command had been specified.
2583 variable is implied for this automatically spawned editor session.
2585 When a message is edited while being composed,
2586 its header is included in the editable text.
2587 The `To:', `Cc:', `Bcc:', `Subject:', `From:', `Reply-To:', `Sender:',
2588 and 'Organization:' fields are accepted within the header,
2589 other fields are ignored.
2591 If set, an empty mailbox file is not removed.
2592 This may improve the interoperability with other mail user agents
2593 when using a common folder directory.
2595 If the mailbox is empty \*(UA normally prints `No mail for user' and
2597 If this option is set \*(UA starts even with an empty mailbox.
2603 commands and vice-versa.
2604 .It Va forward-as-attachment
2605 Original messages are normally sent as inline text with the
2608 and only the first part of a multipart message is included.
2609 With this option messages are sent as MIME `message/rfc822' attachments
2610 with all of their parts included.
2615 options are ignored when the
2616 .Va forward-as-attachment
2619 When replying to a message \*(UA normally removes the comment parts of
2621 which by convention contain the full names of the recipients.
2622 If this variable is set such stripping is not performed,
2623 and comments are retained.
2625 Causes the header summary to be written at startup and after commands
2626 that affect the number of messages or the order of messages in the
2627 current folder; enabled by default.
2628 The command line option
2633 This option is used to hold messages in the system mailbox by default.
2635 \*(OP Can be used to turn off the automatic conversion of domain names
2636 according to the rules of IDNA (internationalized domain names for
2638 Since the IDNA code assumes domain names are specified with the
2640 character set, an UTF-8 locale charset is required to represent
2641 all possible international domain names (before conversion, that is).
2643 Ignore interrupt signals from the terminal while entering messages;
2644 instead echo them as `@' characters and discard the current line.
2646 An option related to
2650 which makes \*(UA refuse to accept a `control-D' as the end of a message.
2651 This option also applies to \*(UA command mode.
2652 .It Va imap-use-starttls
2653 \*(OP Causes \*(UA to issue a `STARTTLS' command to make an unencrypted
2654 IMAP session SSL/TLS encrypted.
2655 This functionality is not supported by all servers,
2656 and is not used if the session is already encrypted by the IMAPS method.
2657 .It Va imap-use-starttls-USER@HOST
2659 .Va imap-use-starttls
2660 for a specific account.
2662 This option causes \*(UA to truncate the user's system mailbox instead
2663 of deleting it when it is empty.
2664 This should always be set since it prevents malicious users from
2665 creating fake mail folders in a world-writable spool directory.
2667 When a message is saved it is usually discarded from the originating
2668 folder when \*(UA is quit.
2669 Setting this option causes all saved message to be retained.
2670 .It Va line-editor-disable
2671 Turn off any enhanced command line editing capabilities (see
2672 .Sx "Command line editor"
2675 When a message is replied to and this variable is set,
2676 it is marked as having been answered.
2677 This mark has no technical meaning in the mail system;
2678 it just causes messages to be marked in the header summary,
2679 and makes them specially addressable.
2680 .It Va message-id-disable
2681 By setting this option the generation of `Message-ID:' can be completely
2682 suppressed, effectively leaving this task up to the mail-transfer-agent
2683 (MTA) or the SMTP server.
2684 (According to RFC 5321 your SMTP server is not required to add this
2685 field by itself, so you should ensure that it accepts messages without
2688 Usually, when a group is expanded that contains the sender,
2689 the sender is removed from the expansion.
2690 Setting this option causes the sender to be included in the group.
2691 .It Va mime-allow-text-controls
2692 When sending messages, each part of the message is MIME-inspected in
2693 order to classify the `Content-Type:' and `Content-Transfer-Encoding:'
2694 that is required to send this part over mail transport, i.e.,
2695 a computation rather similar to what the
2697 command produces when used with the
2701 This classification however treats text files which are encoded in
2702 UTF-16 (often found for HTML files) and similar character sets as binary
2703 octet-streams, forcefully changing any `text/plain' or `text/html'
2704 specification to `application/octet-stream';
2705 if that actually happens, then a yet unset charset MIME parameter is set
2706 to `binary', effectively making it impossible for the receiving MUA to
2707 automatically interpret the contents of the part.
2709 If this option is set, and the data was unambiguously identified as text
2710 data at first glance (by a `.txt' or `.html' file extension), then the
2711 original `Content-Type:' will not be overwritten.
2712 .It Va mime-counter-evidence
2713 Normally the `Content-Type:' field is used to decide how to treat
2714 a messages MIME part.
2715 Some MUAs however don't use
2717 or a similar mechanism to correctly classify content,
2718 but simply specify `application/octet-stream',
2719 even for plain text attachments like `text/diff'.
2720 If this variable is set then \*(UA will use the file extension of
2721 attachments to classify such MIME message parts, if possible.
2723 Causes the filename given in the
2726 and the sender-based filenames for the
2730 commands to be interpreted relative to the directory given in the
2732 variable rather than to the current directory,
2733 unless it is set to an absolute pathname.
2735 If set, each message the
2737 command prints out is followed by a formfeed character.
2739 Send messages to the
2741 command without performing MIME and character set conversions.
2742 .It Va pop3-bulk-load
2743 \*(OP When accessing a POP3 server \*(UA loads the headers of the
2744 messages, and only requests the message bodies on user request.
2745 For the POP3 protocol this means that the message headers will be
2747 If this option is set then \*(UA will download only complete messages
2748 from POP3 servers instead.
2751 a macro that temporarily sets this option, then accesses a POP3 account
2752 that is known to only get small text messages, and then unsets this
2755 \*(OP Unless this variable is set the `APOP' authentication method
2756 will be used when connecting to a POP3 server that advertises support.
2757 The advantage of APOP over `USER/PASS' authentication is that the
2758 password is not sent in clear text over the wire and that only a single
2759 packet is sent for the user/password tuple.
2760 .It Va pop3-no-apop-HOST
2761 \*(IN Disables the `APOP' authentication method for a specific host.
2762 .It Va pop3-no-apop-USER@HOST
2763 Disables the `APOP' authentication method for a specific account.
2764 .It Va pop3-use-starttls
2765 \*(OP Causes \*(UA to issue a `STLS' command to make an unencrypted POP3
2766 session SSL/TLS encrypted.
2767 This functionality is not supported by all servers,
2768 and is not used if the session is already encrypted by the POP3S method.
2769 .It Va pop3-use-starttls-HOST
2771 .Va pop3-use-starttls
2772 for a specific host.
2773 .It Va pop3-use-starttls-USER@HOST
2775 .Va pop3-use-starttls
2776 for a specific account.
2777 .It Va print-all-chars
2778 This option causes all characters to be considered printable.
2779 It is only effective if given in a startup file.
2780 With this option set some character sequences in messages may put the
2781 user's terminal in an undefined state when printed;
2782 it should only be used as a last resort if no working system locale can
2784 .It Va print-alternatives
2785 When a MIME message part of type `multipart/alternative' is displayed
2786 and it contains a subpart of type `text/plain',
2787 other parts are normally discarded.
2788 Setting this variable causes all subparts to be displayed,
2789 just as if the surrounding part was of type `multipart/mixed'.
2791 Suppresses the printing of the version when first invoked.
2792 .It Va quote-as-attachment
2793 If this is set, then the original message is added in its entirety
2794 as a `message/rfc822' MIME attachment when replying to a message.
2795 Note this works regardless of the setting of
2797 .It Va recipients-in-cc
2798 On group replies, specify only the sender of the original mail in `To:'
2799 and mention it's other recipients in the secondary `Cc:'.
2800 .It Va record-resent
2801 If both this variable and the
2808 commands save messages to the
2810 folder as it is normally only done for newly composed messages.
2811 .It Va reply-in-same-charset
2812 If this variable is set \*(UA first tries to use the same character set
2813 of the original message for replies.
2814 If this fails, the mechanism described in
2815 .Sx "Character sets"
2816 is evaluated as usual.
2818 Reverses the sense of
2823 .It Va rfc822-body-from_
2824 This variable can be used to force the display of a so-called `From_'
2825 line for messages that are embedded into an envelope mail via the
2826 `message/rfc822' MIME mechanism.
2828 When the user aborts a message with two `RUBOUT' (interrupt,
2829 `control-C') characters,
2830 \*(UA will copy the partial letter to the file
2832 This option is set by default.
2833 .It Va searchheaders
2834 Expand message-list specifiers in the form `/x:y' to all messages
2835 containing the substring `y' in the header field `x'.
2836 The string search is case insensitive.
2837 .It Va sendcharsets-else-ttycharset
2838 \*(OP If this variable is set, but
2840 is not, then \*(UA acts as if
2842 had been set to the value of the variable
2844 In effect this combination passes through the message data in the
2845 character set of the current locale (given that
2847 hasn't been set manually), i.e., without converting it to the
2849 fallback character set.
2850 Thus, mail message text will be in `ISO-8859-1' encoding when send from
2851 within a `ISO-8859-1' locale, and in `UTF-8' encoding when send from
2852 within an `UTF-8' locale.
2853 If no character set conversion capabilities are available in \*(UA then
2854 the only supported character set is
2857 When sending a message wait until the MTA exits before accepting further
2859 If the MTA returns a non-zero exit status,
2860 the exit status of \*(ua will also be non-zero.
2862 Setting this option causes \*(UA to start at the last message instead of
2863 the first one when opening a mail folder.
2865 Causes \*(UA to use the sender's real name instead of the plain address
2866 in the header field summary and in message specifications.
2868 Causes the recipient of the message to be shown in the header summary
2869 if the message was sent by the user.
2870 .It Va skipemptybody
2871 If an outgoing message does not contain any text in its first or only
2873 do not send it but discard it silently (see also the command line option
2876 .It Va smime-force-encryption
2877 \*(OP Causes \*(UA to refuse sending unencrypted messages.
2879 \*(OP S/MIME sign outgoing messages with the user's private key and
2880 include the user's certificate as a MIME attachment.
2881 Signing a message enables a recipient to verify that the sender used
2882 a valid certificate,
2883 that the email addresses in the certificate match those in the message
2884 header and that the message content has not been altered.
2885 It does not change the message text,
2886 and people will be able to read the message as usual.
2890 .Va smime-sign-include-certs .
2891 .It Va smime-no-default-ca
2892 \*(OP Don't load default CA locations when verifying S/MIME signed
2894 .It Va smtp-use-starttls
2895 \*(OP Causes \*(UA to issue a `STARTTLS' command to make an SMTP session
2897 Not all servers support this command \(en because of common
2898 implementation defects it can't be automatically determined whether
2899 a server supports it or not.
2900 .It Va ssl-no-default-ca
2901 \*(OP Don't load default CA locations to verify SSL/TLS server
2904 \*(OP Accept SSLv2 connections.
2905 These are normally not allowed because this protocol version is insecure.
2906 .It Va keep-content-length
2907 When (editing messages and) writing MBOX mailbox files \*(UA can be told
2908 to keep the `Content-Length:' and `Lines:' header fields that some MUAs
2909 generate by setting this variable.
2910 Since \*(UA does neither use nor update these non-standardized header
2911 fields (which in itself shows one of their conceptual problems),
2912 stripping them should increase interoperability in between MUAs that
2913 work with with same mailbox files.
2914 Note that, if this is not set but
2915 .Va writebackedited ,
2916 as below, is, a possibly performed automatic stripping of these header
2917 fields already marks the message as being modified.
2919 Setting this option enables upward compatibility with \*(UA version 15.0
2920 in respect to which configuration options are available and how they are
2922 This manual uses \*(IN and \*(OU to refer to the new and the old way of
2923 doing things, respectively.
2925 Setting this option, also controllable via the command line option
2927 causes \*(UA to be more verbose, so that, e.g., certificate chains will
2928 be displayed on the users terminal.
2929 Setting this binary options twice increases the level of verbosity, in
2930 which case even details of the actual message delivery and protocol
2931 conversations are also shown.
2934 is sufficient to disable verbosity as such.
2935 .It Va writebackedited
2936 If this variable is set messages modified using the
2940 commands are written back to the current folder when it is quit;
2941 it is only honoured for writable folders in `mbox' format, though.
2942 Note that the editor will be pointed to the raw message content in that
2943 case, i.e., neither MIME decoding nor decryption will have been
2945 and proper RFC 4155 `From ' quoting of newly added or edited content is
2946 also left as an excercise to the user.
2950 .\" .Ss "Value options" {{{
2952 The value options include the following:
2953 .Bl -tag -width ".Va autoprint"
2955 A sequence of characters to print in the `attribute' column of a header
2957 each for one type of messages in the following order:
2958 new (N), unread but old (U), new but read (R), read and old (O), saved
2959 (S), preserved (P), mboxed (M), flagged (F), answered (A), draft (T),
2960 start of a collapsed thread (+), collapsed (\-), classified as spam ($).
2961 The default is `NUROSPMFAT+\-$',
2962 or `NU\ \ *HMFAT+\-$' if
2966 environment variable are set.
2968 Specifies a list of recipients to which a blind carbon copy of each
2969 outgoing message will be sent automatically.
2971 Specifies a list of recipients to which a carbon copy of each outgoing
2972 message will be sent automatically.
2974 Causes sorted mode (see the
2976 command) to be entered automatically with the value of this option as
2977 sorting method when a folder is opened.
2979 The value that should appear in the `charset=' parameter of
2980 `Content-Type:' MIME header fields when no character set conversion of
2981 the message data was performed.
2982 This defaults to `US-ASCII', and the chosen character set should be
2983 `US-ASCII' compatible.
2985 \*(OP The default 8 bit character set that is used as an implied last
2986 member of the variable
2988 Defaults to `UTF-8'.
2989 If no character set conversion capabilities are available in \*(UA then
2990 the only supported character set is
2992 Refer to the section
2993 .Sx "Character sets"
2994 for the complete picture of character set conversion in \*(UA.
2996 The default value for the
3000 \*(OP The colour specification for so-called `From_' lines.
3002 .Sx "Coloured message display"
3003 for the format of the value.
3004 .It Va colour-header
3005 \*(OP The colour specification for header lines.
3007 .Sx "Coloured message display"
3008 for the format of the value.
3009 .It Va colour-msginfo
3010 \*(OP The colour specification for the introductional message info line.
3012 .Sx "Coloured message display"
3013 for the format of the value.
3014 .It Va colour-pagers
3015 \*(OP A comma-separated list of
3017 s for which coloured message display can be used.
3018 Note that only a substring comparison is performed, meaning that the
3019 string `lesser' will match the string `less'.
3021 .Sx "Coloured message display"
3023 The default is set to the sole string `less'.
3024 .It Va colour-partinfo
3025 \*(OP The colour specification for MIME part info lines.
3027 .Sx "Coloured message display"
3028 for the format of the value.
3030 \*(OP A comma-separated list of
3032 inals for which coloured message display can be used.
3035 .Dl cons25,linux,rxvt,rxvt-unicode,\:screen,\:sun,\:vt100,\:vt220,\:\
3036 wsvt25,\:xterm,\:xterm-color
3037 .It Va colour-uheader
3038 \*(OP The colour specification for those header lines that have been
3040 .Va colour-user-headers
3043 .Sx "Coloured message display"
3044 for the format of the value.
3045 .It Va colour-user-headers
3046 A comma separated list of (case-insensitive) header names which should
3047 be colourized with the alternative
3050 The default value is `from,subject'.
3052 The valued option crt is used as a threshold to determine how long
3053 a message must be before
3058 is set without a value then the height of the terminal screen stored in
3059 the system is used to compute the threshold (see
3065 The name of the file to use for saving aborted messages.
3066 This defaults to `dead.letter' in the user's home directory.
3068 The date in a header summary is normally the date of the mailbox `From\ '
3069 line of the message.
3070 If this variable is set, then the date as given in the `Date:' field is
3071 used, converted to local time.
3072 It is possible to control the display of the date by assigning a value,
3075 function will be used to format the date accordingly.
3076 Please read your system manual for the available formats.
3077 Note that the `%n' format should not be used, because \*(UA doesn't
3078 take embedded newlines into account when calculating how many lines fit
3080 .It Va datefield-markout-older
3081 This option, when set in addition to
3083 modifies the display of messages that are not really current in a way
3084 that is rather comparable to the
3089 The interpretation of the value is identical to what has been described
3093 Pathname of the text editor to use in the
3098 A default editor is used if this value is not defined.
3100 Suggestion for the MIME encoding to use in outgoing text messages
3102 Valid values are the default `quoted-printable', `8bit' and `base64'.
3103 `8bit' may cause problems with when transferring mail messages over
3104 channels that are not ESMTP (RFC 1869) compliant.
3105 If there is no need to encode a message,
3106 `7bit' transfer mode is always used regardless of this variable.
3107 Binary data is always encoded as `base64'.
3109 If defined, the first character of this option
3110 gives the character to use in place of `~' to denote tilde escapes.
3112 The name of the directory to use for storing folders of messages.
3113 All folder names that begin with `+' refer to files below it.
3114 The same special conventions as documented for the
3116 command may be used when specifying a new value for
3118 but be aware that the expansion is fully performed immediately.
3119 E.g., if the expanded name refers to an IMAP account, all names that
3120 begin with `+' refer to IMAP mailboxes below the
3124 Note: some IMAP servers do not accept the creation of mailboxes in
3125 the hierarchy base, but require that they are created as subfolders of
3126 `INBOX' \(en with such servers a folder name of the form
3128 .Dl imaps://mylogin@imap.myisp.example/INBOX.
3130 should be used (the last character is the server's hierarchy delimiter).
3131 Folder names prefixed by `+' will then refer to folders below `INBOX',
3132 while folder names prefixed by `@' refer to folders below the hierarchy
3136 namespace command for a method to detect the appropriate prefix and
3139 When a folder is opened and this variable is set,
3140 the macro corresponding to the value of this variable is executed.
3141 The macro is also invoked when new mail arrives,
3142 but message lists for commands executed from the macro
3143 only include newly arrived messages then.
3144 .It Va folder-hook-fullname
3145 When a folder named `fullname' is opened,
3146 the macro corresponding to the value of this variable is executed.
3147 Unlike other folder specifications,
3148 the fully expanded name of a folder, without metacharacters,
3149 is used to avoid ambiguities.
3150 The macro specified with
3152 is not executed if this variable is effective for a folder
3155 ed from within the actually executed macro).
3157 The address (or a list of addresses) to put into the `From:' field of
3158 the message header, quoting RFC 5322:
3159 the author(s) of the message, that is, the mailbox(es) of the person(s)
3160 or system(s) responsible for the writing of the message.
3161 If replying to messages these addresses are handled as if they were in
3165 If the machine's hostname is not valid at the Internet (for example at
3166 a dialup machine) then either this variable or
3171 adds even more fine-tuning capabilities),
3175 contains more than one address,
3178 variable is required (according to the standard RFC 5322).
3180 The string to print before the text of a message with the
3184 .Va forward-as-attachment
3186 Defaults to `-------- Original Message --------' if unset.
3187 No heading is printed if it is set to the empty string.
3189 A format string to use for the header summary,
3193 A `%' character introduces a format specifier.
3194 It may be followed by a number indicating the field width.
3195 If the (possibly implicitly implied) field width is negative, the field
3196 is to be left-aligned.
3197 Valid format specifiers are:
3198 .Bl -tag -offset indent -width "%%"
3202 The date when the message was received.
3204 The indenting level in threaded mode.
3206 The address of the message sender.
3208 The message thread structure.
3209 (Note that this format doesn't support a field width.)
3211 The number of lines of the message.
3215 The number of octets (bytes) in the message.
3217 Message subject (if any).
3219 Message subject (if any) in double quotes.
3221 The position in threaded/sorted order.
3223 A `>' for the current message, otherwise ` '.
3225 A `<' for the current message, otherwise ` '.
3227 The spam score of the message, as has been classified via the command
3233 The default is `%>\&%a\&%m\ %-18f\ %16d\ %4l/%\-5o\ %i%-s',
3234 or `%>\&%a\&%m\ %20-f\ \ %16d\ %3l/%\-5o\ %i%-S' if
3239 .It Va headline-bidi
3240 Bidirectional text requires special treatment when displaying headers,
3241 because numbers (in dates or for file sizes etc.) will not affect the
3242 current text direction, in effect resulting in ugly line layouts when
3243 arabic or other right-to-left text is to be displayed.
3244 On the other hand only a minority of terminals is capable to correctly
3245 handle direction changes, so that user interaction is necessary for
3247 Note that extended host system support is required nonetheless, e.g.,
3248 detection of the terminal character set is one precondition;
3249 and this feature only works in an Unicode (i.e., UTF-8) locale.
3251 In general setting this variable will cause \*(UA to encapsulate text
3252 fields that may occur when printing
3254 with special Unicode control sequences;
3255 it is possible to fine-tune the terminal support level by assigning
3257 no value (or any value other than `1', `2' and `3') will make \*(UA
3258 assume that the terminal is capable to properly deal with Unicode
3259 version 6.3, in which case text is embedded in a pair of U+2068 (FIRST
3260 STRONG ISOLATE) and U+2069 (POP DIRECTIONAL ISOLATE) characters.
3261 In addition no space on the line is reserved for these characters.
3263 Weaker support is chosen by using the value `1' (Unicode 6.3, but
3264 reserve the room of two spaces for writing the control sequences onto
3266 The values `2' and `3' select Unicode 1.1 support (U+200E, LEFT-TO-RIGHT
3267 MARK); the latter again reserves room for two spaces in addition.
3269 Use this string as hostname when expanding local addresses instead of
3270 the value obtained from
3274 i.e., in `Message-ID:' and `From:' fields.
3277 transport is not used then it is normally the responsibility of the MTA
3278 to create these fields, \*(IN in conjunction with
3282 also influences the results;
3283 you should produce some test messages with the desired combination of
3290 \*(OP Sets the IMAP authentication method.
3291 Valid values are `login' for the usual password-based authentication
3293 `cram-md5', which is a password-based authentication that does not send
3294 the password over the network in clear text,
3295 and `gssapi' for GSS-API based authentication.
3296 .It Va imap-auth-USER@HOST
3297 Sets the IMAP authentication method for a specific account.
3299 \*(OP Enables caching of IMAP mailboxes.
3300 The value of this variable must point to a directory that is either
3301 existent or can be created by \*(UA.
3302 All contents of the cache can be deleted by \*(UA at any time;
3303 it is not safe to make assumptions about them.
3304 .It Va imap-keepalive
3305 \*(OP IMAP servers may close the connection after a period of
3306 inactivity; the standard requires this to be at least 30 minutes,
3307 but practical experience may vary.
3308 Setting this variable to a numeric `value' greater than 0 causes
3309 a `NOOP' command to be sent each `value' seconds if no other operation
3311 .It Va imap-list-depth
3312 \*(OP When retrieving the list of folders on an IMAP server, the
3314 command stops after it has reached a certain depth to avoid possible
3316 The value of this variable sets the maximum depth allowed.
3318 If the folder separator on the current IMAP server is a slash `/',
3319 this variable has no effect and the
3321 command does not descend to subfolders.
3323 String used by the `~m', `~M' and `~R' tilde escapes and by the
3325 option for indenting messages,
3326 in place of the normal tabulator character (`^I'), which is the default.
3327 Be sure to quote the value if it contains spaces or tabs.
3329 Pathname of the directory lister to use in the
3331 command when operating on local mailboxes.
3334 .It Va line-editor-cursor-right
3335 \*(OP If the builtin command line editor is used, actions which are
3336 based on rightwise movement may not work on some terminals.
3337 If you encounter such problems, set this variable to the terminal
3338 control sequence that is necessary to move the cursor one column to the
3340 The default is `\\033[C', which should work for most terminals.
3341 Less often occur `\\033OC' and `\\014'.
3342 Note that `ESCAPE' and other control character have to be written as
3343 shell-style escape sequences, e.g., `\\033' for `ESCAPE'.
3345 Is used as the user's mailbox, if set.
3346 Otherwise, a system-dependent default is used.
3347 Supports a logical subset of the special conventions that are documented
3354 The name of the mbox file.
3355 Supports a logical subset of the special conventions that are documented
3361 The fallback default is `mbox' in the user's home directory.
3362 .It Va mimetypes-load-control
3363 This option can be used to control which of the
3365 MIME type databases are loaded by \*(UA.
3366 If the letter `u' (or `U') is part of this options value, then the
3369 file will be loaded (if it exists);
3370 likewise the letter `s' (or `S') controls loading of the system wide
3371 .Pa /etc/mime.types .
3372 If this option is not set \*(UA will try to load both files instead.
3373 Incorporation of the MIME types that are compiled into \*(UA cannot be
3375 .It Va NAIL_EXTRA_RC
3376 The name of an optional startup file to be read after \*(ur.
3377 This variable is ignored if it is imported from the environment;
3378 it has an effect only if it is set in \*(UR or \*(ur to allow bypassing
3379 the configuration with, e.g., `MAILRC=/dev/null'.
3380 Use this file for commands that are not understood by other \*(UA
3383 A string to put at the beginning of each new message.
3384 The escape sequences `\et' (tabulator) and `\en' (newline) are understood.
3385 .It Va NAIL_HISTFILE
3386 \*(OP If a command line editor is available then this can be set to
3387 name the (expandable) path of the location of a permanent history file.
3388 .It Va NAIL_HISTSIZE
3389 \*(OP If a command line editor is available this value restricts the
3390 amount of history entries that are saved into a set and valid
3392 A value of less than 0 disables this feature;
3393 note that loading and incorporation of
3395 upon program startup can also be suppressed by doing this.
3396 An unset or invalid value, or 0, causes a default value to be used.
3397 Dependent on the available command line editor this will also define the
3398 number of history entries in memory;
3399 it is also editor-specific wether runtime updates of this value will be
3402 A string to put at the end of each new message.
3403 The escape sequences `\et' (tabulator) and `\en' (newline) are understood.
3405 If this variable has the value `maildir',
3406 newly created local folders will be in `maildir' format.
3408 Checks for new mail in the current folder each time the prompt is
3410 For IMAP mailboxes the server is then polled for new mail,
3411 which may result in delayed operation if the connection to the server is
3413 A `maildir' folder must be re-scanned to determine if new mail has
3416 If this variable is set to the special value `nopoll' an IMAP server is
3417 not actively asked for new mail,
3418 but new mail may still be detected and announced with any other IMAP
3419 command that is sent to the server.
3420 A `maildir' folder is not scanned, then.
3422 In either case the IMAP server may send notifications about messages
3423 that have been deleted on the server by another process or client.
3424 In this case, `Expunged X messages' is printed regardless of this
3426 and message numbers may have changed.
3428 The value to put into the `Organization:' field of the message header.
3430 Pathname of the program to use in the more command or when the
3433 The default paginator is
3436 \*(IN Sets a global fallback password, which is used in case none has
3437 been given in the protocol and account-specific URL and neither is there
3438 a matching `password-USER@HOST' nor a matching `password-HOST';
3439 as a last resort \*(UA will ask for a password on the user's terminal if
3440 the authentication method requires a password.
3441 Specifying passwords in a startup file is generally a security risk;
3442 the file should be readable by the invoking user only.
3443 .It Va password-HOST
3446 for accounts on a specific host.
3447 .It Va password-USER@HOST
3452 for a specific account.
3454 Set the password for `user' when connecting to `host'.
3455 If no such variable is defined for a host,
3456 the user will be asked for a password on standard input.
3457 Specifying passwords in a startup file is generally a security risk;
3458 the file should be readable by the invoking user only.
3459 .It Va pipe-content/subcontent
3460 When a MIME message part of `content/subcontent' type is displayed or
3462 its text is filtered through the value of this variable interpreted as
3465 The special value `@' can be used to force interpretation of the message
3466 part as plain text, e.g., `set pipe-application/pgp-signature=@' will
3467 henceforth treat signatures as plain text and display them "as is".
3469 Also, if a normal shell command is prefixed with `@', then the command
3470 will only be used to prepare the MIME message part if the message is
3471 displayed by itself, but not when multiple messages are displayed at
3474 Finally, if a normal shell command is prefixed with `@&', then, in
3475 addition to what has been described for the plain `@' shell command
3476 prefix, the command will be run asynchronously, i.e., without blocking
3477 \*(UA, which may be a handy way to display a, e.g., PDF file while also
3478 continuing to read the mail message.
3480 Special care must be taken when using such commands as mail viruses may
3481 be distributed by this method;
3482 if messages of type `application/x-sh' were filtered through the shell,
3484 a message sender could easily execute arbitrary code on the system \*(UA
3486 .It Va pop3-keepalive
3487 \*(OP POP3 servers close the connection after a period of inactivity;
3488 the standard requires this to be at least 10 minutes,
3489 but practical experience may vary.
3490 Setting this variable to a numeric `value' greater than 0 causes
3491 a `NOOP' command to be sent each `value' seconds if no other operation
3494 The string printed when a command is accepted.
3495 Prompting may be prevented by either setting this to the null string
3498 The same XSI escape sequences that are understood by the
3500 command may be used within
3503 In addition, the following \*(UA specific additional sequences are
3505 `\\&', which expands to `?' unless
3507 is set, in which case it expands to `&';
3508 note that "\\& " is the default value for
3510 `\\?', which will expand to `1' if the last command failed, and to `0'
3512 `\\$', which will expand to the name of the currently active
3514 if any, and to the empty string otherwise,
3515 and `\\@', which will expand to the name of the currently active mailbox.
3516 (Note that the prompt buffer is size-limited, excess is cut off.)
3518 When a newer version of the
3520 .Sx "Command line editor"
3521 is used, any escape sequence must itself be encapsulated with another
3522 escape character for usage with the
3524 mechanism: \*(UA configures the control character `\\01' for this.
3526 If set, \*(UA starts a replying message with the original message
3527 prefixed by the value of the variable
3529 Normally, a heading consisting of `Fromheaderfield wrote:' is printed
3530 before the quotation.
3531 If the string `noheading' is assigned to the
3533 variable, this heading is omitted.
3534 If the string `headers' is assigned, the headers selected by the
3535 .Ic ignore Ns / Ns Ic retain
3536 commands are printed above the message body,
3539 acts like an automatic `~m' tilde escape command, then.
3540 If the string `allheaders' is assigned, all headers are printed above
3541 the message body and all MIME parts are included,
3544 act like an automatic `~M' command.
3546 .Va quote-as-attachment .
3548 \*(OP Can be set in addition to
3550 Setting this turns on a more fancy quotation algorithm in that leading
3551 quotation characters are compressed and overlong lines are folded.
3553 can be set to either one or two (space separated) numeric values,
3554 which are interpreted as the maximum (goal) and the minimum line length,
3555 respectively, in a spirit rather equal to the
3557 program, but line-, not paragraph-based.
3558 If not set explicitly the minimum will reflect the goal algorithmically.
3559 The goal can't be smaller than the length of
3561 plus some additional pad.
3562 Necessary adjustments take place silently.
3564 If defined, gives the pathname of the folder used to record all outgoing
3566 If not defined, then outgoing mail is not saved.
3567 When saving to this folder fails the message is not sent,
3568 but instead saved to
3571 A list of addresses to put into the `Reply-To:' field of the message
3573 Members of this list are handled as if they were in the
3577 When \*(UA initially prints the message headers it determines the number
3578 to print by looking at the speed of the terminal.
3579 The faster the terminal, the more it prints.
3580 This option overrides this calculation and specifies how many message
3581 headers are printed.
3582 This number is also used for scrolling with the
3586 \*(OP A comma-separated list of character set names that can be used in
3587 outgoing Internet mail.
3588 The value of the variable
3590 is automatically appended to this list of character-sets.
3591 If no character set conversion capabilities are compiled into \*(UA then
3592 the only supported charset is
3595 .Va sendcharsets-else-ttycharset
3596 and refer to the section
3597 .Sx "Character sets"
3598 for the complete picture of character set conversion in \*(UA.
3600 An address that is put into the `Sender:' field of outgoing messages,
3601 quoting RFC 5322: the mailbox of the agent responsible for the actual
3602 transmission of the message.
3603 This field should normally not be used unless the `From:' field contains
3604 more than one address, on which case it is required.
3607 address is handled as if it were in the
3611 To use an alternate mail delivery system,
3612 set this option to the full pathname of the program to use.
3613 It may be necessary to set
3614 .Va sendmail-progname
3616 .It Va sendmail-progname
3617 Many systems use a so-called
3619 environment to ensure compatibility with
3621 This works by inspecting the name that was used to invoke the mail
3623 If this variable is set then the mailwrapper (the program that is
3624 actually executed when calling `sendmail') will treat its contents as
3626 The default is `sendmail'.
3628 Pathname of the shell to use in the
3630 command and the `~!' tilde escape.
3631 A default shell is used if this option is not defined.
3633 A string for use with the `~A' tilde escape.
3635 A string for use with the `~a' tilde escape.
3637 Must correspond to the name of a readable file if set.
3638 The file's content is then appended to each singlepart message
3639 and to the first part of each multipart message.
3640 Be warned that there is no possibility to edit the signature for an
3643 \*(OP Specifies a directory with CA certificates in PEM (Privacy
3644 Enhanced Mail) format for verification of S/MIME signed messages.
3645 .It Va smime-ca-file
3646 \*(OP Specifies a file with CA certificates in PEM format for
3647 verification of S/MIME signed messages.
3648 .It Va smime-cipher-USER@HOST
3649 \*(OP Specifies a cipher to use when generating S/MIME encrypted
3650 messages for the specified account.
3651 RFC 5751 mandates a default of `aes-128' (AES-128 CBC).
3653 The actually available cipher algorithms depend on the cryptographic
3654 library that \*(UA uses; possible values are, in decreasing cipher
3656 `aes-256' (AES-256 CBC), `aes-192' (AES-192 CBC), `aes-128' (AES-128 CBC),
3657 `des3' (DES EDE3 CBC, 168 bits; default if `aes-128' isn't available)
3658 and `des' (DES CBC, 56 bits).
3660 The following ciphers have been obsoleted and are no longer mentioned by
3661 the S/MIME specification (RFC 5751), but may be selected if available:
3662 `rc2-64' (RC2 CBC, 64 bits) and `rc2-40' (RC2 CBC, 40 bits).
3663 .It Va smime-crl-file
3664 \*(OP Specifies a file that contains a CRL in PEM format to use when
3665 verifying S/MIME messages.
3666 .It Va smime-crl-dir
3667 \*(OP Specifies a directory that contains files with CRLs in PEM format
3668 to use when verifying S/MIME messages.
3669 .It Va smime-encrypt-USER@HOST
3670 \*(OP If this variable is set, messages send to the given receiver are
3671 encrypted before sending.
3672 The value of the variable must be set to the name of a file that
3673 contains a certificate in PEM format.
3675 If a message is sent to multiple recipients,
3676 each of them for whom a corresponding variable is set will receive an
3677 individually encrypted message;
3678 other recipients will continue to receive the message in plain text
3680 .Va smime-force-encryption
3682 It is recommended to sign encrypted messages, i.e., to also set the
3685 .It Va smime-sign-cert
3686 \*(OP Points to a file in PEM format.
3687 For the purpose of signing and decryption this file needs to contain the
3688 user's private key as well as his certificate.
3690 For the purpose of encryption the recipient's public encryption key
3691 (certificate) is expected; the command
3693 can be used to save certificates of signed messages (the section
3694 .Sx "Signed and encrypted messages with S/MIME"
3695 gives some details).
3696 This mode of operation is usually driven via
3697 .Va smime-sign-cert-USER@HOST ,
3699 .It Va smime-sign-cert-USER@HOST
3702 for a specific account.
3703 For message signing `USER@HOST' is always derived from the value of
3705 (or, if that contains multiple addresses,
3709 When decrypting messages the account is derived from the recipient
3710 fields (`To:' and `Cc:') of the message, which are searched for
3711 addresses for which such a variable is set.
3712 \*(UA always uses the first address that matches,
3713 so if the same message is sent to more than one of the user's addresses
3714 using different encryption keys, decryption might fail.
3715 .It Va smime-sign-include-certs
3716 \*(OP If used, this is supposed to a consist of a comma-separated list
3717 of files, each of which containing a single certificate in PEM format to
3718 be included in the S/MIME message in addition to the
3721 This is most useful for long certificate chains if it is desired to aid
3722 the receiving party's verification process.
3723 Note that top level certificates may also be included in the chain but
3724 don't play a role for verification.
3728 .Va smime-sign-cert-USER@HOST .
3729 .It Va smime-sign-include-certs-USER@HOST
3731 .Va smime-sign-include-certs
3732 for a specific account.
3734 \*(OP Normally \*(UA invokes the program defined via
3736 to transfer messages.
3739 variable will instead cause `SMTP' network connections be made to the
3740 server specified therein in order to directly submit the message.
3741 \*(UA knows about three different "SMTP protocols":
3742 .Bl -bullet -offset indent
3744 The plain `SMTP' protocol (RFC 5321) that normally lives on the
3745 server port 25 and requires setting of the
3746 .Va smtp-use-starttls
3747 variable as above to enter a SSL/TLS encrypted session state.
3748 Assign a value like \*(IN `[smtp://][user[:password]@]server[:port]'
3749 (\*(OU `[smtp://]server[:port]')
3750 to choose this protocol.
3752 Then the so-called `SMTPS' which is supposed to live on server port 465
3753 and is automatically SSL/TLS secured.
3754 Unfortunately it never became a standardized protocol and may thus not
3755 be supported by your hosts network service database
3756 \(en in fact the port number has already been reassigned to other
3759 `SMTPS' is nonetheless a commonly offered "protocol" and thus can be
3760 chosen by assigning a value like \*(IN
3761 `smtps://[user[:password]@]server[:port]'
3762 (\*(OU `smtps://server[:port]');
3763 due to the mentioned problems it is usually necessary to explicitly
3764 specify the port as `:465', however.
3766 Finally there is the `SUBMISSION' protocol (RFC 6409), which usually
3767 lives on server port 587 and is practically identically to the `SMTP'
3768 protocol from \*(UAs point of view beside that; it requires setting the
3769 .Va smtp-use-starttls
3770 variable to enter a SSL/TLS secured session state.
3771 Assign a value like \*(IN `submission://[user[:password]@]server[:port]'
3772 (\*(OU `submission://server[:port]').
3775 \*(IN If `user' or `password' contain special characters, in particular
3776 whitespace, `/', `:' or `%', they must be specified in URL notation
3779 may be helpful for preparation).
3781 The SMTP transfer is executed in a child process, which runs
3782 asynchronously unless either the
3787 If it receives a TERM signal, it will abort and save the message to
3790 \*(OP Sets the SMTP authentication method.
3791 Possible values are `none' (the default), `plain', `login'
3792 as well as the \*(OPal methods `cram-md5' and `gssapi'.
3793 The `none' method doesn't need any user credentials,
3794 `gssapi' requires a user name
3795 and all other methods require a user name and a password.
3802 .Va smtp-auth-password
3804 .Va smtp-auth-user Ns
3806 .It Va smtp-auth-HOST
3809 for SMTP accounts on a specific host.
3810 .It Va smtp-auth-USER@HOST
3813 for a specific account.
3814 (\*(OU For specific values of sender addresses, dependend upon the variable
3817 .It Va smtp-auth-password
3818 \*(OP \*(OU Sets the global fallback password for SMTP authentication.
3819 If the authentication method requires a password, but neither
3820 .Va smtp-auth-password
3822 .Va smtp-auth-password-USER@HOST
3824 \*(UA will ask for a password on the user's terminal.
3825 .It Va smtp-auth-password-USER@HOST
3827 .Va smtp-auth-password
3828 for specific values of sender addresses, dependent upon the variable
3830 .It Va smtp-auth-user
3831 \*(OP \*(OU Sets the global fallback user name for SMTP authentication.
3832 If the authentication method requires a user name, but neither
3835 .Va smtp-auth-user-USER@HOST
3837 \*(UA will ask for a user name on the user's terminal.
3838 .It Va smtp-auth-user-USER@HOST
3841 for specific values of sender addresses, dependent upon the variable
3843 .It Va smtp-hostname
3844 \*(IN Normally \*(UA uses the variable
3846 to derive the necessary `USER@HOST' information to issue a
3847 `MAIL FROM:<>' SMTP command.
3850 can be used to use the `USER' from the SMTP account
3855 and the `HOST' from the content of this variable
3856 (or, if that is the empty string,
3858 or the local hostname as a last resort).
3859 Setting this variable also influences the generated `Message-Id:'.
3861 \*(OP The path to the spam detector.
3862 Note that the path is not expanded, but used "as is".
3863 A fallback path will have been compiled into the \*(UA binary if the
3865 executable had been found during compilation.
3867 \*(OP Can be used to specify the host on which
3869 listens for connections; if not set, defaults to `localhost'.
3871 \*(OP Spam detectors like
3873 decline to work with messages which exceed a specific size;
3874 if this variable is set then \*(UA won't even try to pass messages which
3875 exceed the given limit.
3876 The default is 420000 bytes.
3878 \*(OP Can be used to explicitly specify the port on which
3880 listens for connections.
3882 \*(OP If the spam detector listens on a path-based UNIX domain socket,
3883 then setting this variable to the fully qualified path will force its
3884 usage for communication.
3886 \*(OP This can be used to support multiple, per-used configuration files
3887 of the spam detector.
3888 Note that \*(UA doesn't automatically set this to reflect a possibly set
3892 \*(OP Specifies a directory with CA certificates in PEM (Pricacy
3893 Enhanced Mail) for verification of of SSL/TLS server certificates.
3895 .Xr SSL_CTX_load_verify_locations 3
3896 for more information.
3898 \*(OP Specifies a file with CA certificates in PEM format for
3899 verification of SSL/TLS server certificates.
3901 .Xr SSL_CTX_load_verify_locations 3
3902 for more information.
3904 \*(OP Sets the file name for a SSL/TLS client certificate required by
3906 .It Va ssl-cert-USER@HOST
3907 Sets an account-specific file name for a SSL/TLS client certificate
3908 required by some servers.
3911 for the specified account.
3912 .It Va ssl-cipher-list
3913 \*(OP Specifies a list of ciphers for SSL/TLS connections.
3916 for more information.
3918 \*(OP Specifies a file that contains a CRL in PEM format to use when
3919 verifying SSL/TLS server certificates.
3921 \*(OP Specifies a directory that contains files with CRLs in PEM format
3922 to use when verifying SSL/TLS server certificates.
3924 \*(OP Sets the file name for the private key of a SSL/TLS client
3926 If unset, the name of the certificate file is used.
3927 The file is expected to be in PEM format.
3928 .It Va ssl-key-USER@HOST
3929 Sets an account-specific file name for the private key of a SSL/TLS
3933 for the specified account.
3935 \*(OP Selects the used TLS/SSL protocol version.
3936 The actually available protocol versions depend on the TLS/SSL
3937 library that \*(UA uses; possible values are, from newest to oldest:
3938 `tls1.2', `tls1.1', `tls1', `ssl3' and `ssl2'.
3942 to any of these values will fixate the used protocol, which means that
3943 connections will fail if the server doesn't support it.
3944 The value `auto', which is the default, chooses a compatibility method
3945 that automatically uses the newest protocol version that the server
3946 is capable to understand.
3948 It has to be noted that `auto' is used as a fallback method if
3949 the actual setting of
3951 isn't supported by the used TLS/SSL library \(em in this case an error
3952 message will be printed first, however.
3953 .It Va ssl-method-USER@HOST
3956 for a specific account.
3958 \*(OP Gives the pathname to an entropy daemon socket, see
3960 .It Va ssl-rand-file
3961 \*(OP Gives the pathname to a file with entropy data, see
3962 .Xr RAND_load_file 3 .
3963 If the file is a regular file writable by the invoking user,
3964 new data is written to it after it has been loaded.
3966 \*(OP Sets the action to be performed if an error occurs during SSL/TLS
3967 server certificate validation.
3969 `strict' (fail and close connection immediately),
3970 `ask' (ask whether to continue on standard input),
3971 `warn' (print a warning and continue),
3972 `ignore' (do not perform validation).
3973 The default is `ask'.
3974 .It Va ssl-verify-USER@HOST
3977 for a specific account.
3979 If only set without an assigned value, then this option inhibits the
3980 generation of the `Message-Id:' and `User-Agent:' header fields that
3981 include obvious references to \*(UA.
3982 There are two pitfalls associated with this:
3983 First, the message id of outgoing messages is not known anymore.
3984 Second, an expert may still use the remaining information in the header
3985 to track down the originating mail user agent.
3986 If set to the value `noagent', then the mentioned `Message-Id:'
3987 suppression doesn't occur.
3989 If defined, gives the number of lines of a message to be printed out
3990 with the top command;
3991 normally, the first five lines are printed.
3993 The character set of the terminal \*(UA operates on,
3994 and the one and only supported character set that \*(UA can use if no
3995 character set conversion capabilities have been compiled into it,
3996 in which case it defaults to `ISO-8859-1' unless it can deduce a value
3997 from the `LC_CTYPE' locale environment.
3998 Refer to the section
3999 .Sx "Character sets"
4000 for the complete picture about character sets.
4002 \*(IN Sets a global fallback user name, which is used in case none has
4003 been given in the protocol and account-specific URL and there is also
4006 This variable defaults to the value of
4011 for a specific host.
4013 Pathname of the text editor to use in the
4015 command and `~v' tilde escape.
4019 .\" .Sh ENVIRONMENT {{{
4021 Besides the variables described above,
4022 \*(UA uses the following environment variables:
4023 .Bl -tag -width ".It Va MAILRC"
4025 The user's preferred width in column positions for the terminal screen
4026 or window (only used during startup).
4028 The user's home directory.
4029 .It Va LANG , Va LC_ALL , Va LC_COLLATE , Va LC_CTYPE , Va LC_MESSAGES
4033 The user's preferred number of lines on a page or the vertical screen or
4034 window size in lines (only used during startup).
4036 Is used as a startup file instead of \*(ur if set.
4037 When \*(UA scripts are invoked on behalf of other users,
4038 this variable should be set to
4040 to avoid side-effects from reading their configuration files.
4042 If this variable is set and
4044 is not, it is treated as a startup configuration file and read.
4045 .It Va NAIL_NO_SYSTEM_RC
4046 If this variable is set then reading of \*(UR at startup is inhibited,
4047 i.e., the same effect is achieved as if \*(UA had been started up with
4051 Changes the letters printed in the first column of a header summary.
4053 \*(OP The terminal type for which output is to be prepared.
4055 Used as directory for temporary files instead of
4059 Can be used to force identification as
4061 i.e., identical to the
4063 command line option.
4069 .Bl -tag -width ".It Pa /etc/mime.types"
4071 File giving initial commands.
4073 System wide initialization file.
4074 .It Pa ~/.mime.types
4075 Personal MIME types.
4076 .It Pa /etc/mime.types
4077 System wide MIME types.
4081 .\" .Sh EXAMPLES {{{
4084 .\" .Ss "Getting started" {{{
4085 .Ss "Getting started"
4086 The \*(UA command has two distinct usages, according to whether one
4087 wants to send or receive mail.
4088 Sending mail is simple: to send a message to a user whose email address
4089 is, say, `<bill@host.example>', use the shell command:
4091 .Dl $ \*(ua bill@host.example
4093 then type your message.
4094 \*(UA will prompt you for a message `Subject:' first;
4095 after that, lines typed by you form the body of the message.
4096 When you reach the end of the message,
4097 type an EOT (`control\-D') at the beginning of a line,
4098 which will cause \*(UA to echo `EOT' and return you to the shell.
4100 If, while you are composing the message you decide that you do not wish
4101 to send it after all, you can abort the letter by typing two `RUBOUT'
4102 (interrupt, `control-C') characters.
4103 Typing a single `RUBOUT' causes \*(UA to print
4104 .Ns ` Ns Li (Interrupt -- one more to kill letter) Ns '.
4105 Typing a second `RUBOUT' causes \*(UA to save your partial letter on the
4108 and abort the letter.
4109 Once you have sent mail to someone, there is no way to undo the act, so
4112 If you want to send the same message to several other people,
4113 you can list their email addresses on the command line.
4114 .Bd -literal -offset indent
4115 $ \*(ua sam@workstation.example bob@server.example
4117 Tuition fees are due next Friday. Don't forget!
4123 will sendout to `<sam@workstation.example>' and `<bob@server.example>'.
4124 To read your mail, simply type
4128 \*(UA will respond by typing its version number and date and then
4129 listing the messages you have waiting.
4130 Then it will type a prompt and await your command.
4131 The messages are assigned numbers starting with 1 \(en you refer to the
4132 messages with these numbers.
4133 \*(UA keeps track of which messages are `new' (have been sent since you
4134 last read your mail) and `read' (have been read by you).
4135 New messages have an `N' next to them in the header listing and old,
4136 but unread messages have a `U' next to them.
4137 \*(UA keeps track of new/old and read/unread messages by putting a
4138 header field called `Status' into your messages.
4140 To look at a specific message, use the
4142 command, which may be abbreviated to simply `t'.
4143 For example, if you had the following messages:
4144 .Bd -literal -offset indent
4145 O 1 drfoo@myhost.example Wed Sep 1 19:52 5/421 "Fees"
4146 O 2 sam@friends.example Thu Sep 2 00:08 30/895
4149 you could examine the first message by giving the command:
4153 which might cause \*(UA to respond with, for example:
4154 .Bd -literal -offset indent
4155 [-- Message 1 -- 5 lines, 421 bytes --]:
4156 From drfoo@myhost.example Wed Sep 1 19:52:25 2004
4160 Tuition fees are due next Wednesday. Don't forget!
4163 Many \*(UA commands that operate on messages take a message number as an
4164 argument, just as the shown
4167 For these commands, there is a notion of a current message.
4168 When you enter the \*(UA program,
4169 the current message is initially the first (or the first recent) one.
4170 Thus, you can often omit the message number and use, for example, `t` to
4171 type the current message.
4172 As a further shorthand, you can type a message by simply giving its
4173 message number \(en hence `1` would type the first message.
4175 Frequently, it is useful to read the messages in your mailbox in order,
4177 You can read the next message in \*(UA by simply typing a newline.
4178 As a special case, you can type a newline as your first command to
4179 \*(UA to type the first message.
4181 If, after typing a message, you wish to immediately send a reply,
4182 you can do so with the command
4186 takes a message number as an argument.
4187 \*(UA then begins a message addressed to the user who sent you the
4188 message and let you type in your letter in reply, followed by
4189 a `<control-D>' at the beginning of a line, as before.
4191 Note that \*(UA copies the subject header from the original message.
4192 This is useful in that correspondence about a particular matter will
4193 tend to retain the same subject heading, making it easy to recognize.
4194 If there are other header fields in the message, like `Cc:',
4195 the information found will also be used.
4197 Sometimes you will receive a message that has been sent to several
4198 people and wish to reply only to the person who sent it.
4200 (with a capital `R') replies to a message, but sends a copy to the
4203 If you wish, while reading your mail, to send a message to someone,
4204 but not as a reply to one of your messages, you can send the message
4207 command, which takes as arguments the names of the recipients you wish
4209 For example, to send a message to `<frank@machine.example>':
4211 .Dl mail frank@machine.example
4213 To delete a message from the mail folder, you can use the command
4215 In addition to not saving deleted messages,
4216 \*(UA will not let you type them, either.
4217 The effect is to make the message disappear altogether, along with its
4220 Many features of \*(UA can be tailored to your liking with the
4222 command; it has two forms, depending on whether you are setting
4223 a `binary' or a `valued' option.
4224 Binary options are either on or off \(en for example, the
4226 option informs \*(UA that each time you send a message, you want it to
4227 prompt you for a `Cc:' header to be included in the message.
4230 option, you would type
4234 Valued options are values which \*(UA uses to adapt to your tastes.
4237 option tells \*(UA where to save messages sent by you,
4238 and is specified by, e.g.,
4242 Note that no spaces are allowed in `set record=Sent'.
4244 \*(UA includes a simple facility for maintaining groups of messages
4245 together in folders.
4246 To use the folder facility, you must tell \*(UA where you wish to keep
4248 Each folder of messages will be a single file.
4249 For convenience, all of your folders are kept in a single directory of
4251 To tell \*(UA where your folder directory is, put a line of the form
4253 .Dl set folder=letters
4256 If, as in the example above, your folder directory does not begin with
4257 a `/', \*(UA will assume that your folder directory is to be found
4258 starting from your home directory.
4260 Anywhere a file name is expected, you can use a folder name, preceded
4262 For example, to put a message into a folder with the
4264 command, you can use:
4268 to save the current message in the `classwork' folder.
4269 If the `classwork' folder does not yet exist, it will be created.
4270 Note that messages which are saved with the
4272 command are automatically removed from your system mailbox.
4274 In order to make a copy of a message in a folder without causing
4275 that message to be removed from your system mailbox, use the
4277 command, which is identical in all other respects to the
4284 can be used to direct \*(UA to the contents of a different folder.
4287 .Dl folder +classwork
4289 directs \*(UA to read the contents of the `classwork' folder.
4290 All of the commands that you can use on your system mailbox are also
4291 applicable to folders, including
4296 To inquire which folder you are currently editing, use `folder' without
4298 And to list your current set of folders, use the
4304 command is available to print out a brief summary of the most important
4307 While typing in a message to be sent to others it is often useful to be
4308 able to invoke the text editor on the partial message, print the
4309 message, execute a shell command, or do some other auxiliary function.
4310 \*(UA provides these capabilities through `tilde escapes',
4311 which consist of a tilde (`~') at the beginning of a line, followed by
4312 a single character which indicates the function to be performed.
4313 For example, to print the text of the message so far, use:
4317 which will print a line of dashes, the recipients of your message, and
4318 the text of the message so far.
4319 A list of the most important tilde escapes is available with `~?'.
4322 .\" .Ss "IMAP or POP3 client setup" {{{
4323 .Ss "IMAP or POP3 client setup"
4324 \*(OP First you need the following data from your ISP:
4325 the host name of the IMAP or POP3 server,
4326 user name and password for this server,
4327 and a notice whether the server uses SSL/TLS encryption.
4328 Assuming the SSL/TLS secured host name of your IMAP account is
4329 `server.myisp.example' and your user name for that server is `mylogin',
4330 you could refer to this account using the
4334 command line option with
4336 .Dl imaps://mylogin@server.myisp.example
4338 (This string is not necessarily the same as your Internet mail address.)
4339 Even if the server does not accept IMAPS or POP3S connections,
4340 it is possible that it supports the `STARTTLS' method of upgrading
4341 already connected, but not yet authenticated sessions to use SSL/TLS
4343 The only reliable method to see if this works is to try it; enter one of
4345 .Dl set imap-use-starttls
4346 .Dl set pop3-use-starttls
4348 before you initiate the connection, dependent on the actual protocol.
4350 As you probably want messages to be deleted from this account
4351 after saving them, prefix it with `%:'.
4354 command can be used to avoid typing that many characters every time you
4357 .Dl shortcut myisp %:imaps://mylogin@server.myisp.example
4359 You might want to put this string into a startup file.
4361 is one of those commands that are specific to \*(UA and will thus
4362 confuse other implementations of POSIX
4364 so it should possibly not be placed in \*(ur.
4367 .Dl set NAIL_EXTRA_RC=.\*(uarc
4369 in \*(ur and create a file
4371 containing all the commands that are specific to \*(UA.
4372 You can then access your remote mailbox by invoking
4376 on the command line, or by executing
4381 If you want to use more than one IMAP mailbox on a server,
4382 or if you want to use the IMAP server for mail storage too, the
4384 command (which is also \*(UA-specific) is possibly more appropriate.
4385 You can put the following in
4387 .Bd -literal -offset indent
4389 set folder=imaps://mylogin@server.myisp.example
4390 set record=+Sent MBOX=+mbox outfolder
4394 and can then access incoming mail for this account by invoking
4395 `\*(ua \-A myisp' on the command line or by executing `ac myisp' within
4397 After that, a command like `copy 1 +otherfolder' will refer to
4398 `otherfolder' on the IMAP server.
4399 In particular, `fi&' will change to the `mbox' folder,
4400 and `fi+Sent' will show your recorded sent mail,
4401 with both folders located on the IMAP server.
4403 \*(UA will ask you for a password string each time you connect to
4405 If you can reasonably trust the security of your workstation,
4406 you can give this password in the startup file as
4408 .Dl set password-mylogin@server.myisp.example="SECRET"
4410 You should change the permissions of this file to 0600, see
4413 \*(UA supports different authentication methods for both IMAP and POP3.
4414 If Kerberos is used at your location,
4415 you can try to activate (the optional) GSS-API based authentication via
4417 .Dl set imap-auth=gssapi
4419 The advantage of this method is that \*(UA doesn't need to know your
4420 password at all, nor does it have to send sensitive data over the network.
4421 If that isn't possible, try to use authentication methods that at least
4422 avoid sending the password in clear over the wire, which is especially
4423 important if SSL/TLS cannot be used, e.g.,
4425 .Dl set imap-auth=cram-md5
4427 For POP3 \*(UA will try to use the `APOP' mechanism automatically unless
4428 explicitly disabled.
4429 If the server does not offer any such authentication methods,
4430 conventional user/password based authentication must be used.
4431 It is sometimes helpful, especially when setting up an account or when
4432 there are authentification problems, to enable verbosity by setting the
4434 option \(en \*(UA will display all data sent to the server in clear text
4435 on the screen when this option is set.
4436 (Because this may also include passwords you should take care that no
4437 unauthorized person can look at your terminal when this option is set.)
4439 If you regularly use the same workstation to access IMAP accounts,
4440 you can greatly enhance performance by enabling local caching of IMAP
4442 For any message that has been fully or partially fetched from the server,
4443 a local copy is made and is used when the message is accessed again,
4444 so most data is transferred over the network once only.
4445 To enable the IMAP cache, select a local directory name and put
4447 .Dl set imap-cache=~/localdirectory
4449 in the (\*(UA-specific) startup file.
4450 All files within that directory can be overwritten or deleted by \*(UA
4452 so you should not use the directory to store other information.
4454 Once the cache contains some messages,
4455 it is not strictly necessary anymore to open a connection to the IMAP
4456 server to access them.
4457 When \*(UA is invoked with the option
4462 only cached data is used for any folder you open.
4463 Messages that have not yet been completely cached are not available
4464 then, but all other messages can be handled as usual.
4465 Changes made to IMAP mailboxes in
4467 mode are committed to the IMAP server next time it is used in
4470 Synchronizing the local status with the status on the server is thus
4471 partially within your responsibility;
4472 if you forget to initiate a connection to the server again before you
4473 leave your location,
4474 changes made on one workstation are not available on others.
4475 Also if you alter IMAP mailboxes from a workstation while uncommitted
4476 changes are still pending on another,
4477 the latter data may become invalid.
4478 The same might also happen because of internal server status changes.
4479 You should thus carefully evaluate this feature in your environment
4480 before you rely on it.
4482 Many servers will close the connection after a short period of
4483 inactivity \(en use one of
4485 .Dl set pop3-keepalive=30
4486 .Dl set imap-keepalive=240
4488 to send a keepalive message each 30 seconds for POP3,
4489 or each 4 minutes for IMAP.
4491 If you encounter problems connecting to a SSL/TLS server,
4496 variables (see the OpenSSL FAQ for more information) or specify the
4497 protocol version with
4499 Contact your ISP if you need a client certificate or if verification of
4500 the server certificate fails.
4501 If the failed certificate is indeed valid,
4502 fetch its CA certificate by executing the shell command
4504 .Dl $ </dev/null openssl s_client \-showcerts \-connect \e
4505 .Dl \ \ \ \ \ \ server.myisp.example:imaps 2>&1 | tee log.txt
4509 ) and put it into the file specified with
4511 The data you need is located at the end of the certificate chain
4512 within (and including) the `BEGIN CERTIFICATE'
4513 and `END CERTIFICATE' lines.
4514 Note that the example above is \fBinsecure\fR!
4515 One should use the `-verify' and `-CAfile' options of
4517 to be "on the safe side" regarding the fetched certificates.
4520 .\" .Ss "Reading HTML mail" {{{
4521 .Ss "Reading HTML mail"
4526 utility or another command-line web browser that can write plain text to
4529 .Dl set pipe-text/html="elinks -force-html -dump 1"
4530 .Dl set pipe-text/html="lynx -stdin -dump -force_html"
4532 will cause HTML message parts to be converted into a more friendly form.
4535 .\" .Ss "Viewing PDF attachments" {{{
4536 .Ss "Viewing PDF attachments"
4537 Most PDF viewers do not accept input directly from a pipe.
4538 It is thus necessary to store the attachment in a temporary file first:
4540 .Dl set pipe-application/pdf="@&cat >/tmp/\*(ua$$.pdf; \e
4541 .Dl \ \ \ \ \ \ acroread /tmp/\*(ua$$.pdf; rm /tmp/\*(ua$$.pdf"
4543 Note that security defects are discovered in PDF viewers from time to
4545 Automatical command execution like this can compromise your system
4547 in particular if you stay not always informed about such issues.
4550 .\" .Ss "Signed and encrypted messages with S/MIME" {{{
4551 .Ss "Signed and encrypted messages with S/MIME"
4552 \*(OP S/MIME provides two central mechanisms:
4553 message signing and message encryption.
4554 A signed message contains some data in addition to the regular text.
4555 The data can be used to verify that the message was sent using a valid
4556 certificate, that the sender's address in the message header matches
4557 that in the certificate, and that the message text has not been altered.
4558 Signing a message does not change its regular text;
4559 it can be read regardless of whether the recipient's software is able to
4561 It is thus usually possible to sign all outgoing messages if so desired.
4562 Encryption, in contrast, makes the message text invisible for all people
4563 except those who have access to the secret decryption key.
4564 To encrypt a message, the specific recipient's public encryption key
4566 It is thus not possible to send encrypted mail to people unless their
4567 key has been retrieved from either previous communication or public key
4569 A message should always be signed before it is encrypted.
4570 Otherwise, it is still possible that the encrypted message text is
4573 A central concept to S/MIME is that of the certification authority (CA).
4574 A CA is a trusted institution that issues certificates.
4575 For each of these certificates it can be verified that it really
4576 originates from the CA, provided that the CA's own certificate is
4578 A set of CA certificates is usually delivered with OpenSSL and installed
4580 If you trust the source of your OpenSSL software installation,
4581 this offers reasonable security for S/MIME on the Internet.
4582 In general, a certificate cannot be more secure than the method its CA
4583 certificate has been retrieved with, though.
4584 Thus if you download a CA certificate from the Internet,
4585 you can only trust the messages you verify using that certificate as
4586 much as you trust the download process.
4588 The first thing you need for participating in S/MIME message exchange is
4589 your personal certificate, including a private key.
4590 The certificate contains public information, in particular your name and
4591 your email address, and the public key that is used by others to encrypt
4593 and to verify signed messages they supposedly received from you.
4594 The certificate is included in each signed message you send.
4595 The private key must be kept secret.
4596 It is used to decrypt messages that were previously encrypted with your
4597 public key, and to sign messages.
4599 For personal use it is recommended that you get a S/MIME certificate
4600 from one of the major CAs on the Internet using your WWW browser.
4601 (Many CAs offer such certificates for free.)
4602 You will usually receive a combined certificate and private key in
4603 PKCS#12 format which \*(UA does not directly accept.
4604 To convert it to PEM format, use the following shell command:
4606 .Dl $ openssl pkcs12 \-in cert.p12 \-out cert.pem \-clcerts \-nodes
4608 If you omit the `\-nodes' parameter, you can specifiy an additional `PEM
4609 pass phrase' for protecting the private key.
4610 \*(UA will then ask you for that pass phrase each time it signs or
4614 .Dl set smime-sign-cert-myname@myisp.example=cert.pem
4616 to make this private key and certificate known to \*(UA.
4617 You can now sign outgoing messages.
4623 From each signed message you send,
4624 the recipient can fetch your certificate and use it to send encrypted
4626 Accordingly if somebody sends you a signed message, you can do the same.
4629 command to check the validity of the certificate.
4630 After that, retrieve the certificate and tell \*(UA that it should use
4633 .Dl certsave filename
4634 .Dl set smime-encrypt-USER@HOST=filename
4636 You should carefully consider if you prefer to store encrypted messages
4638 If you do, anybody who has access to your mail folders can read them,
4639 but if you do not, you might be unable to read them yourself later if
4640 you happen to lose your private key.
4643 command saves messages in decrypted form, while the
4648 commands leave them encrypted.
4650 Note that neither S/MIME signing nor encryption applies to message
4651 subjects or other header fields.
4652 Thus they may not contain sensitive information for encrypted messages,
4653 and cannot be trusted even if the message content has been verified.
4654 When sending signed messages,
4655 it is recommended to repeat any important header information in the
4659 .\" .Ss "Using CRLs with S/MIME or SSL/TLS" {{{
4660 .Ss "Using CRLs with S/MIME or SSL/TLS"
4661 \*(OP Certification authorities (CAs) issue certificate revocation
4662 lists (CRLs) on a regular basis.
4663 These lists contain the serial numbers of certificates that have been
4664 declared invalid after they have been issued.
4665 Such usually happens because the private key for the certificate has
4667 because the owner of the certificate has left the organization that is
4668 mentioned in the certificate, etc.
4669 To seriously use S/MIME or SSL/TLS verification,
4670 an up-to-date CRL is required for each trusted CA.
4671 There is otherwise no method to distinguish between valid and
4672 invalidated certificates.
4673 \*(UA currently offers no mechanism to fetch CRLs, nor to access them on
4674 the Internet, so you have to retrieve them by some external mechanism.
4676 \*(UA accepts CRLs in PEM format only;
4677 CRLs in DER format must be converted, like, e.\|g.:
4679 .Dl $ openssl crl \-inform DER \-in crl.der \-out crl.pem
4681 To tell \*(UA about the CRLs, a directory that contains all CRL files
4682 (and no other files) must be created.
4687 variables, respectively, must then be set to point to that directory.
4688 After that, \*(UA requires a CRL to be present for each CA that is used
4689 to verify a certificate.
4692 .\" .Ss "Handling spam" {{{
4694 \*(OP \*(UA can make use of spam detection and learning facilities \(en
4695 more precisely, SpamAssassin (\%<http://spamassassin.apache.org>).
4696 A very comprehensive documentation of
4698 can be found at the O'Reilly Commons
4699 (\%<http://commons.oreilly.com/wiki/index.php/SpamAssassin>).
4701 Currently \*(UA supports interaction with
4703 only via its daemonized
4706 server / client pair, which means that, in order to detect and work
4707 with spam through \*(UA, an instance of the
4709 daemon must be running (the examples are equivalent):
4710 .Bd -literal -offset indent
4711 $ spamd -i localhost:2142 -i /tmp/.spamsock -d [-L] [-l]
4712 $ spamd --listen=localhost:2142 --listen=/tmp/.spamsock \\
4713 --daemonize [--local] [--allow-tell]
4718 should only listen on a local, path-based UNIX domain socket instead of
4719 offering its service over the network, it maybe necessary to use
4722 option instead of the shown
4724 In order to support training of the Bayesian classifier through \*(UA,
4726 must have been started with the
4732 is running \*(UA can classify messages by using the client side program,
4735 .Bd -literal -offset indent
4736 $ \*(ua -Sspam-command=/usr/local/bin/spamc \\
4737 -Sspam-socket=/tmp/.spamsock -Sspam-maxsize=500000
4740 The commands offered are
4744 which simply set an `is-spam' flag that can be used for, e.g., message
4747 which passes messages through to the spam detector in order to gain
4748 a spam score and conditionally set the `is-spam' flag accordingly,
4749 as well as the Bayesian filter related
4755 Because messages must exist on local storage in order to be scored (or
4756 used for Bayesian filter training), it is possibly a good idea to
4757 perform the local spam check last:
4758 .Bd -literal -offset indent
4759 define spamdelhook {
4761 spamset (header x-dcc-brand-metrics "bulk")
4762 # Server-side spamassassin(1)
4763 spamset (header x-spam-flag "YES")
4764 del :s # TODO we HAVE to be able to do `spamrate :u ! :s'
4765 # And finally the local spamc(1)
4769 set folder-hook-FOLDER=spamdelhook
4772 See also the documentation for the variables
4782 .\" .Ss "Sending mail from scripts" {{{
4783 .Ss "Sending mail from scripts"
4784 If you want to send mail from scripts, you must be aware that \*(UA
4785 reads the user's configuration files by default.
4786 So unless your script is only intended for your own personal use
4787 (as, e.g., a cron job), you need to circumvent this:
4789 .Dl MAILRC=/dev/null \*(ua \-n
4791 You then need to create a script-local configuration for \*(UA.
4792 This can be done by either pointing the
4794 variable to a custom configuration file,
4795 by passing the configuration in environment variables,
4798 command line option to specify options.
4799 Since many configuration options are not valid shell variables, the
4801 command is useful if the approach via environment variables is used:
4802 .Bd -literal -offset indent
4803 env MAILRC=/dev/null password=secret \*(ua -n -Sv15-compat \e
4804 -S 'smtp=smtps://mylogin@some.host:465' -Ssmtp-auth=login \e
4805 -S 'from=scriptreply@domain' \e
4806 -s 'subject' -a attachment_file recipient@domain < content_file
4811 .\" .Sh "SEE ALSO" {{{
4824 .Xr spamassassin 1 ,
4842 .\" .Sh "IMPLEMENTATION NOTES" {{{
4843 .Sh "IMPLEMENTATION NOTES"
4844 The character set conversion uses and relies upon the
4847 Its functionality differs widely between the various system environments
4850 Limitations with IMAP mailboxes are:
4851 It is not possible to edit messages, but it is possible to append them.
4852 Thus to edit a message, create a local copy of it, edit it, append it,
4853 and delete the original.
4854 The line count for the header display is only appropriate if the entire
4855 message has been downloaded from the server.
4856 The marking of messages as `new' is performed by the IMAP server;
4861 will not cause it to be reset, and if the
4863 variable is unset, messages that arrived during a session will not be
4864 in state `new' anymore when the folder is opened again.
4865 Also if commands queued in disconnected mode are committed,
4866 the IMAP server will delete the `new' flag for all messages in the
4868 and new messages will appear as unread when it is selected for viewing
4870 The `flagged', `answered', and `draft' attributes are usually permanent,
4871 but some IMAP servers are known to drop them without notification.
4872 Message numbers may change with IMAP every time before the prompt is
4873 printed if \*(UA is notified by the server that messages have been
4874 deleted by some other client or process.
4875 In this case, `Expunged n messages' is printed, and message numbers may
4878 Limitations with POP3 mailboxes are:
4879 It is not possible to edit messages, they can only be copied and deleted.
4880 The line count for the header display is only appropriate if the entire
4881 message has been downloaded from the server.
4882 The status field of a message is maintained by the server between
4883 connections; some servers do not update it at all, and with a server
4884 that does, the `exit' command will not cause the message status to be
4886 The `newmail' command and the `newmail' variable have no effect.
4887 It is not possible to rename or to remove POP3 mailboxes.
4889 If a `RUBOUT' (interrupt, `control-C') is typed while an IMAP or POP3
4890 operation is in progress, \*(UA will wait until the operation can be
4892 and will then return to the command loop and print the prompt again.
4893 When a second `RUBOUT' is typed while \*(UA is waiting for the operation
4894 to complete, the operation itself will be cancelled.
4895 In this case, data that has not been fetched yet will have to be fetched
4896 before the next command can be performed.
4897 If the cancelled operation was using an SSL/TLS encrypted channel,
4898 an error in the SSL transport will very likely result and render the
4899 connection unusable.
4901 As \*(UA is a mail user agent, it provides only basic SMTP services.
4902 If it fails to contact its upstream SMTP server, it will not make
4903 further attempts to transfer the message at a later time,
4904 and it does not leave other information about this condition than an
4905 error message on the terminal and an entry in
4907 This is usually not a problem if the SMTP server is located in the same
4908 local network as the computer on which \*(UA is run.
4909 However, care should be taken when using a remote server of an ISP;
4910 it might be better to set up a local SMTP server then which just acts as
4913 \*(UA immediately contacts the SMTP server (or
4915 ) even when operating in
4918 It would not make much sense for \*(UA to defer outgoing mail since SMTP
4919 servers usually provide much more elaborated delay handling than \*(UA
4920 could perform as a client.
4921 Thus the recommended setup for sending mail in
4923 mode is to configure a local SMTP server such that it sends outgoing
4924 mail as soon as an external network connection is available again,
4925 i.e., to advise it to do that from a network startup script.
4930 A \fImail\fR command appeared in Version 1 AT&T Unix.
4931 Berkeley Mail was written in 1978 by Kurt Shoens.
4932 This man page is derived from from The Mail Reference Manual originally
4933 written by Kurt Shoens.
4934 "Heirloom Mailx" enhancements are maintained and documented by Gunnar
4936 "S-nail" is maintained and documented by Steffen (Daode) Nurpmeso.
4938 Portions of this text are reprinted and reproduced in electronic form
4939 from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
4940 \(en Operating System Interface (POSIX), The Open Group Base
4941 Specifications Issue 6, Copyright \(co 2001-2003 by the Institute of
4942 Electrical and Electronics Engineers, Inc and The Open Group.
4943 In the event of any discrepancy between this version and the original
4944 IEEE and The Open Group Standard, the original IEEE and The Open Group
4945 Standard is the referee document.
4946 The original Standard can be obtained online at
4947 \%<http://www.opengroup.org/unix/online.html>.
4948 Redistribution of this material is permitted so long as this notice
4954 .An "Christos Zoulas" ,
4955 .An "Gunnar Ritter" ,
4956 .An Steffen Po Daode Pc Nurpmeso Aq s-nail-users@lists.sourceforge.net
4959 Too many (see the file `TODO' from the distribution or the repository).