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
235 option to the MTA when a message is send.
238 argument is given it'll be checked for validity and then fixated to
239 the given value, but otherwise the content of the variable
241 will be used for that purpose \(en i.e., it'll be passed through to
244 option whenever a message is send.
245 A valid non-empty value will also be set as if an additional
246 .Ns ` Ns Li "-Sfrom=VALUE" Ns '
247 option had been used and therefore affect sending of messages via SMTP
248 (as a consideration for `From:').
249 .It Fl S Ar variable Ns Op = Ns value
250 Sets the internal option
252 and, in case of a value option, assigns
255 Even though options set via
257 may be overwritten from within resource files,
258 the command line setting will be reestablished after all resources have
261 Specify the subject on the command line
262 (be careful to quote subjects containing spaces).
264 The message to be sent is expected to contain a message header with
265 `To:', `Cc:', or `Bcc:' fields giving its recipients and `Subject:'
266 giving the subject of the message.
267 Recipients and subject specified on the command line are ignored.
269 Read the system mailbox of
271 (appropriate privileges presumed), and `assume to be'
273 in some aspects, e.g. in respect to expansions of `%' etc.
277 Print \*(UA's version and exit.
281 option causes some verbosity (like printing of certificate chains).
282 Using it twice increases the level of verbosity.
284 Enable tilde escapes even if not in interactive mode.
286 This sets multiple options to prepare \*(UA for working in batch mode
287 (most likely in non-interactive mode):
299 it also enables processing of tilde escapes.
300 E.g., the following should send an email message to `alias'.
302 .Dl printf 'm alias\en~s Subject\enBody\en.\enx\en' | \
303 MAILRC=/dev/null s-nail -n -#
307 .\" .Ss "Sending mail" {{{
309 To send a message to one or more people,
310 \*(UA can be invoked with arguments which are the names of people to
311 whom the mail will be sent.
314 es, plain addresses or full address specifications including user names
316 in which case care for proper quoting may be necessary.
317 If this manual refers to a \fIlist of addresses\fR,
318 then \*(UA expects a comma-separated list of such names.
320 .Sx "Recipient address specifications"
321 below explains the interpretation of names in more detail.
322 The user is then expected to type in his message, followed by a
324 at the beginning of a line.
326 .Sx "Replying to or originating mail"
327 describes some features of \*(UA available to help when composing
331 .\" .Ss "Reading mail" {{{
333 In normal usage \*(UA is given no arguments and checks the user's mail
334 out of the post office,
335 then prints out a one line header of each message found.
336 The current message is initially the first message (numbered 1) and can
339 command, which can be abbreviated `p'.
340 The commands `p+' and `p\-' move forward to the next and backward to the
341 previous message, respectively, and messages can be addressed directly
342 by specifying their message number, as in `p 1'.
345 .\" .Ss "Disposing of mail" {{{
346 .Ss "Disposing of mail"
347 After examining a message the user can
352 Deletion causes the \*(UA program to forget about the message.
353 This is not irreversible;
356 (`u') the message by giving its number,
357 or the \*(UA session can be ended by giving the
360 Deleted messages will, however, usually disappear never to be seen
364 .\" .Ss "Specifying messages" {{{
365 .Ss "Specifying messages"
366 Commands such as print and delete can be given a list of message numbers
367 as arguments to apply to a number of messages at once.
369 .Ns ` Ns Li "delete 1 2" Ns '
370 deletes messages 1 and 2,
372 .Ns ` Ns Li "delete 1-5" Ns '
373 will delete the messages 1 through 5.
374 In sorted or threaded mode (see the
379 .Ns ` Ns Li "delete 1-5" Ns '
380 will delete the messages that are located between (and including)
381 messages 1 through 5 in the sorted/threaded order, as shown in the
383 The following special message names exist:
385 .Bl -tag -width ".It .Ar :n:u"
389 All old messages (any not in state read or new).
393 All deleted messages (for the
399 All `flagged' messages.
401 All answered messages
406 All messages marked as draft.
408 \*(OP All messages classified as spam.
412 The message that was previously the current message.
414 The parent message of the current message,
415 that is the message with the Message-ID given in the `In-Reply-To:' field
416 or the last entry of the `References:' field of the current message.
418 The next previous undeleted message,
419 or the next previous deleted message for the
422 In sorted/threaded mode,
423 the next previous such message in the sorted/threaded order.
425 The next undeleted message,
426 or the next deleted message for the
429 In sorted/threaded mode,
430 the next such message in the sorted/threaded order.
432 The first undeleted message,
433 or the first deleted message for the
436 In sorted/threaded mode,
437 the first such message in the sorted/threaded order.
440 In sorted/threaded mode,
441 the last message in the sorted/threaded order.
444 selects the message addressed with
448 is any other message specification,
449 and all messages from the thread that begins at it.
450 Otherwise it is identical to
455 the thread beginning with the current message is selected.
459 All messages that were included in the message list for the previous
461 .It Ar / Ns Ar string
462 All messages that contain
464 in the subject field (case ignored).
471 the string from the previous specification of that type is used again.
472 .It Xo Op Ar @ Ns Ar name-list Ns
475 All messages that contain the given case-insensitive search
477 ession; if the \*(OPal regular expression (see
481 will be interpreted as one if any of the `magic'al regular expression
484 .Ar @ Ns Ar name-list
485 part is missing, the search is restricted to the subject field body,
488 specifies a comma-separated list of header fields to search, as in
490 .Dl '@to,from,cc@Someone i ought to know'
492 The special names `body' and `text' can be used to search in message
493 bodies \(en whereas the former searches only the body, the latter form
494 also performs a fulltext search in the header fields.
495 In order to search for a string that includes a `@' (commercial at)
498 is effectively non-optional, but may be given as the empty string.
502 By default, this is a case-sensitive search for the complete email
507 only the local part of the addresses is evaluated for the comparison.
511 a case-sensitive search for the complete real name of a sender is
514 .Ns ` Ns Li "(from address)" Ns '
515 expression can be used instead if substring matches are desired.
519 \*(OP IMAP-style SEARCH expressions may also be used.
520 This addressing mode is available with all types of folders;
521 for folders not located on IMAP servers,
522 or for servers unable to execute the SEARCH command,
523 \*(UA will perform the search locally.
524 Strings must be enclosed by double quotes `"' in their entirety
525 if they contain white space or parentheses;
527 only backslash `\e' is recognized as an escape character.
528 All string searches are case-insensitive.
529 When the description indicates that the `envelope' representation of an
530 address field is used,
531 this means that the search string is checked against both a list
534 .Dl ( \*q Ns name Ns \*q \*q Ns source Ns \*q \*q Ns \
535 local-part Ns \*q \*q Ns domain-part Ns \*q )
538 and the addresses without real names from the respective header field.
539 These search expressions can be nested using parentheses, see below for
541 .Bl -tag -width ".It .Ar :n:u"
543 All messages that satisfy the given
545 .It Ar ( criterion1 criterion2 ... criterionN )
546 All messages that satisfy all of the given criteria.
547 .It Ar ( or criterion1 criterion2 )
548 All messages that satisfy either
553 To connect more than two criteria using `or',
554 (or) specifications have to be nested using additional parentheses,
556 .Ns ` Ns Li "(or a (or b c))" Ns ',
558 .Ns ` Ns Li "(or a b c)" Ns '
560 .Ns ` Ns Li "((a or b) and c)" Ns '.
561 For a simple `or' operation of independent criteria on the lowest
563 it is possible to achieve similar effects by using three separate
565 .Ns ` Ns Li "(a) (b) (c)" Ns '.
566 .It Ar ( not criterion )
567 All messages that do not satisfy
569 .It Ar ( bcc \*q Ns Ar string Ns Ar \*q )
570 All messages that contain
572 in the `envelope' representation of the `Bcc:' field.
573 .It Ar ( cc \*q Ns Ar string Ns Ar \*q )
574 All messages that contain
576 in the `envelope' representation of the `Cc:' field.
577 .It Ar ( from \*q Ns Ar string Ns Ar \*q )
578 All messages that contain
580 in the `envelope' representation of the `From:' field.
581 .It Ar ( subject \*q Ns Ar string Ns Ar \*q )
582 All messages that contain
584 in the `Subject:' field.
585 .It Ar ( to \*q Ns Ar string Ns Ar \*q )
586 All messages that contain
588 in the `envelope' representation of the `To:' field.
589 .It Ar ( header name \*q Ns Ar string Ns Ar \*q )
590 All messages that contain
595 .It Ar ( body \*q Ns Ar string Ns Ar \*q )
596 All messages that contain
599 .It Ar ( text \*q Ns Ar string Ns Ar \*q )
600 All messages that contain
602 in their header or body.
603 .It Ar ( larger size )
604 All messages that are larger than
607 .It Ar ( smaller size )
608 All messages that are smaller than
611 .It Ar ( before date )
612 All messages that were received before
614 which must be in the form
615 .Li "d[d]-mon-yyyy" ,
616 where `d' denotes the day of the month as one or two digits,
617 `mon' is the name of the month \(en one of
618 `Jan', `Feb', `Mar', `Apr', `May', `Jun',
619 `Jul', `Aug', `Sep', `Oct', `Nov', or `Dec',
620 and `yyyy' is the year as four digits, e.g., "28-Dec-2012".
622 All messages that were received on the specified date.
623 .It Ar ( since date )
624 All messages that were received since the specified date.
625 .It Ar ( sentbefore date )
626 All messages that were sent on the specified date.
627 .It Ar ( senton date )
628 All messages that were sent on the specified date.
629 .It Ar ( sentsince date )
630 All messages that were sent since the specified date.
632 The same criterion as for the previous search.
633 This specification cannot be used as part of another criterion.
634 If the previous command line contained more than one independent
635 criterion then the last of those criteria is used.
639 .\" .Ss "Replying to or originating mail" {{{
640 .Ss "Replying to or originating mail"
643 can be used to set up a response to a message,
644 sending it back to the person who it was from.
645 Text the user types in, up to an end-of-file,
646 defines the contents of the message.
647 While the user is composing a message \*(UA treats lines beginning with
648 the character `~' specially.
649 For instance, typing `~m' (alone on a line) will place a copy of the
650 current message into the response, each line prefixed by the value of
652 Other escapes will set up subject fields,
653 add and delete recipients to the message,
655 and allow the user to escape to an editor to revise the message
656 or to a shell to run some commands.
657 (These options are given in the summary below.)
660 .\" .Ss "Ending a mail processing session" {{{
661 .Ss "Ending a mail processing session"
662 The user can end a \*(UA session by issuing the
665 Messages which have been examined go to the user's mbox file unless they
667 in which case they are discarded.
668 Unexamined messages go back to the post office.
672 When command line history is tracked, an updated history file is
674 None of these actions is performed when the command
676 (`x') is used instead of
681 .\" .Ss "Personal and systemwide distribution lists" {{{
682 .Ss "Personal and systemwide distribution lists"
683 It is possible to create personal distribution lists so that,
684 for instance, the user can send mail to `cohorts'
685 and have it go to a group of people.
686 Such lists can be defined via the
688 command by, e.g., placing lines like
690 .Dl alias cohorts bill ozalp jkf mark kridle@ucbcory
692 in the file \*(ur in the user's home directory.
695 without arguments lists all the currently known aliases.
697 Please note that this mechanism has nothing in common with the system
698 wide aliases that may be used by the local MTA (mail-transfer-agent)
699 and are often tracked in a file
706 Personal aliases will be expanded by \*(UA before the message is sent.
707 They are a convenient alternative to specifying each addressee by
711 .\" .Ss "Recipient address specifications" {{{
712 .Ss "Recipient address specifications"
713 When an address is used to name a recipient (in `To:', `Cc:', or `Bcc:'),
714 names of local mail folders and pipes to external commands may also be
715 specified \(en the message text is then written to them.
716 The rules are: Any name which starts with a `|' (vertical bar) character
717 specifies a pipe \(en the command string following the `|' is executed
718 and the message is sent to its standard input;
719 any other name which contains a `@' (at sign) character is treated as
721 any other name which starts with a `+' (plus sign) character specifies
723 any other name which contains a `/' (slash) character but no `!'
724 (exclamation mark) or `%' (percent sign) character before also specifies
726 what remains is treated as a mail address.
727 Compressed folders are handled as described for the
732 .\" .Ss "Network mail (Internet / ARPA, UUCP, Berknet)" {{{
733 .Ss "Network mail (Internet / ARPA, UUCP, Berknet)"
736 for a description of network addresses.
737 If support for IDNA (internationalized domain names for applications)
738 has been compiled into \*(UA,
739 then the domain name part of network addresses will be converted via
740 IDNA mechanisms as necessary, effectively treating it as a name in the
744 for the complete picture about character sets.
746 \*(UA has a number of options which can be set in the \*(ur file
747 to alter its behavior; e.g.,
752 .Ic "set idna-disable"
753 will disable the mentioned IDNA conversion even if support is available.
754 (These options are summarized below.)
757 .\" .Ss "MIME types" {{{
759 For any outgoing attachment \*(UA tries to determine the content type.
760 It does this by reading MIME type files whose lines have the following
763 .Dl type/subtype extension [extension ...]
765 where `type/subtype' are strings describing the file contents,
766 and `extension' is the part of a filename starting after the last dot.
767 Any line not immediately beginning with an ASCII alphabetical character
770 .Va mimetypes-load-control
771 can be used to control the sources of MIME types, and the
773 command can be used to show the list of mime types known to \*(UA.
774 If there is a match with the `extension' of the file to attach,
775 the given `type/subtype' pair is used.
776 Otherwise, or if the filename has no extension,
777 the content types `text/plain' or `application/octet-stream' are used,
778 dependent upon file content inspection.
780 .Va mime-allow-text-controls .
783 .\" .Ss "Character sets" {{{
785 \*(UA normally detects the character set of the terminal by using
786 mechanisms that are controlled by the `LC_CTYPE' locale setting,
787 if such are supported; the variable
789 will be set to the detected terminal character set and will thus
790 show up in the output of the command
795 value is not overwritten by this detection mechanism;
796 this feature must be used if the detection doesn't work properly,
797 and it may be used to adjust the name of the locale character set.
798 E.g., on BSD systems one may use a locale with the character set
799 `ISO8859-1', which is not a valid name for this character set;
800 to be on the safe side, one may set
802 to the correct name, `ISO-8859-1'.
804 Note that changing the value doesn't mean much beside that,
805 since several aspects of the real character set are implied by the
806 locale environment of the system,
807 and that stays unaffected by the content of an overwritten
810 (This is mostly an issue when interactively using \*(UA, though.
811 It is actually possible to send mail in a completely "faked" locale
814 If no character set conversion capabilities have been compiled into
817 library has been found), then
819 will be the only supported character set,
820 it is simply assumed that it can be used to exchange 8 bit messages,
821 and the rest of this section does not apply;
822 it may however still be necessary to explicitly set it if automatic
823 detection fails, since in that case it defaults to `ISO-8859-1'.
825 When reading messages, their text is converted into
827 as necessary in order to display them on the users terminal.
828 Unprintable characters and illegal byte sequences are detected
829 and replaced by proper substitution characters
832 was set once \*(UA was started).
834 When sending messages all their parts and attachments are classified.
835 Whereas no character set conversion is performed on those parts which
836 appear to be binary data,
837 the character set being used must be declared within the MIME header of
838 an outgoing text part if it contains characters that do not conform to
839 the set of characters that are allowed by the email standards.
840 Permissible values for character sets can be declared using the
844 which defines a catch-all last-resort fallback character set that is
845 implicitly appended to the list of character-sets in
848 All the specified character sets are tried in order unless the
849 conversion of the part or attachment succeeds.
850 If none of the tried (8 bit) character sets is capable to represent the
851 content of the part or attachment,
852 then the message will not be sent and its text will be saved to
854 In general, if the message `Cannot convert from a to b' appears, either
855 some characters are not appropriate for the currently selected
856 (terminal) character set,
857 or the needed conversion is not supported by the system.
858 In the first case, it is necessary to set an appropriate `LC_CTYPE'
859 locale and/or the variable
862 The best results are usually achieved when \*(UA is run in a UTF-8
863 locale on a UTF-8 capable terminal,
864 in which case the full Unicode spectrum of characters is available.
865 In this setup characters from various countries can be displayed,
866 while it is still possible to use more simple character sets for sending
867 to retain maximum compatibility with older mail clients.
870 .\" .Ss "Command line editor" {{{
871 .Ss "Command line editor"
872 \*(OP \*(UA can be configured to support a command line editor and
873 command history lists which are saved in between sessions.
874 One may link against fully-fledged external libraries
875 .Ns ( Ns Xr readline 3 ,
877 ) or use the \*(UA command line editor instead, which should work in all
878 environments which comply to ISO C (ISO/IEC 9899:1990/Amendment 1:1995).
879 When an external library is used, interactive behaviour of \*(UA relies
880 on that library and may not correspond one-to-one to what is described
883 Regardless of the actually used command line editor history entries
884 will be created for lines entered in command mode only, and creation of
885 such an entry can be forcefully suppressed by starting the line with
887 Note that history handling is by itself an optional feature and may
888 therefore not be available.
889 For more information see the documentation of the options
891 .Va line-editor-disable ,
896 The builtin \*(UA command line editor supports the following operations;
897 the notation `^-character' stands for the combination of the `control'
898 key plus the mentioned character, e.g., `^A' means "hold control key
899 while adding an A key on top of it":
900 .Bl -tag -width "^M^"
902 Go to the start of the line.
904 Move the cursor backward one character.
906 Forward delete the character under the cursor;
907 quits \*(UA if used on the empty line, unless the
911 Go to the end of the line.
913 Move the cursor forward one character.
915 Cancel current operation, full reset.
916 If there is an active history search or tabulator expansion then this
917 command will first reset that, reverting to the former line content;
918 thus a second reset is needed for a full reset in this case.
919 In all cases \*(UA will reset a possibly used multibyte character input
922 The same as `backspace': backward delete one character.
924 \*(OP The same as `horizontal tabulator': try to expand the "word"
926 Here "expansion" refers to the \*(UA expansion, as documented for
928 and thus includes shell word expansion (as a last step).
929 I.e., this is \*(UA "expansion", not what one usually expects from
932 The same as `ENTER': complete this line of input.
934 Delete all characters from the cursor to the end of the line.
938 \*(OP Go to the next history entry.
940 \*(OP Go to the previous history entry.
942 \*(OP Complete the current line from (the remaining older) history entries.
944 The same as `^A' followed by `^K'.
946 Delete the characters from the one preceding the cursor to the preceding
949 Move the cursor forward one word boundary.
951 Move the cursor backward one word boundary.
954 If problems with commands that are based upon rightwise movement are
955 encountered, adjustments of the option
956 .Va line-editor-cursor-right
957 may solve the problem, as documented for it.
959 If the terminal produces key sequences which are compatible with
961 then the left and right cursor keys will map to `^B' and `^F',
962 respectively, the up and down cursor keys will map to `^P' and `^N',
963 and the Home/End/PgUp/PgDown keys will call the
965 command with the respective arguments `0', `$', `-' and `+'
966 (i.e., perform scrolling through the header summary list).
969 .\" .Ss "Coloured message display" {{{
970 .Ss "Coloured message display"
971 \*(OP \*(UA can be configured to support coloured message display.
972 Colours are used only when the
974 environment variable is set and the terminal type can be found in
976 Beyond that, if a command requires to output through the
982 must be mentioned in the variable
984 otherwise no colours will be used regardless of the actual terminal type.
986 "Coloured message display" can be configured through font attributes
987 (`ft=' \(en `bold', `invers' and `underline'), foreground (`fg=') and
988 background (`bg=') colours (`black', `blue', `green', `red', `brown',
989 `magenta', `cyan' and `white').
990 Multiple specifications can be joined in a comma separated list, as in
992 .Dl set colour-msginfo="ft=bold,fg=magenta,bg=cyan"
994 Options to be set are
996 .Va colour-partinfo ,
1000 .Va colour-uheader ,
1002 .Va colour-user-headers ,
1003 which is a list of headers to be colourized via
1005 instead of the default
1007 To forcefully disable colours, set
1008 .Va colour-disable .
1011 .\" .Ss "Commands" {{{
1013 Each command is typed on a line by itself,
1014 and may take arguments following the command word.
1015 The command need not be typed in its entirety \(en
1016 the first command which matches the typed prefix is used.
1019 prints a sorted list of available commands, and the command
1021 when given an argument, will show a documentation string for the
1023 .Ns ` Ns Ic ? Ns Ar unc Ns ' ;
1024 documentation strings are however \*(OP.)
1026 For commands which take message lists as arguments,
1027 if no message list is given,
1028 then the next message forward which satisfies the command's requirements
1030 If there are no messages forward of the current message,
1031 the search proceeds backwards,
1032 and if there are no good messages at all,
1033 \*(UA types `no applicable messages' and aborts the command.
1034 If the command begins with a `#' (number sign) character,
1035 the line is ignored.
1037 The arguments to commands can be quoted, using the following methods:
1038 .Bl -bullet -offset indent
1040 An argument can be enclosed between paired double-quotes `"argument"' or
1041 single-quotes `'argument'';
1042 any white space, shell word expansion, or backslash characters (except
1043 as described next) within the quotes are treated literally as part of
1045 A double-quote will be treated literally within single-quotes and vice
1047 Inside such a quoted string the actually used quote character can be
1048 used nonetheless by escaping it with a backslash `\\', as in
1051 An argument that is not enclosed in quotes, as above, can usually still
1052 contain space characters if those spaces are backslash-escaped.
1054 A backslash outside of the enclosing quotes is discarded
1055 and the following character is treated literally as part of the argument.
1057 An unquoted backslash at the end of a command line is discarded and the
1058 next line continues the command.
1061 Filenames, where expected, are subsequently subjected to the following
1062 transformations, in sequence:
1063 .Bl -bullet -offset indent
1065 If the filename begins with an unquoted plus sign, and the
1067 variable is defined,
1068 the plus sign will be replaced by the value of the
1070 variable followed by a slash.
1073 variable is unset or is set to null, the filename will be unchanged.
1075 Shell word expansions are applied to the filename.
1076 If more than a single pathname results from this expansion and the
1077 command is expecting one file, an error results.
1081 The following commands are provided:
1082 .Bl -tag -width ".Ic account"
1084 Interprets the remainder of the word as a macro name and passes it
1088 .Ns ` Ns Ic ~ Ns Ar mymacro Ns '
1089 is a shorter synonym for
1090 .Ns ` Ns Ic call Ar mymacro Ns ' .
1092 Print out the preceding message.
1093 If given a numeric argument n,
1094 goes to the n'th previous message and prints it.
1096 Prints a brief summary of commands.
1097 \*(OP Given an argument a synopsis for the command in question is
1100 Executes the shell (see
1104 ) command which follows.
1110 (ac) Creates, selects or lists an email account.
1111 An account is formed by a group of commands,
1112 primarily of those to set variables.
1114 of which the second is a `{',
1115 the first argument gives an account name,
1116 and the following lines create a group of commands for that account
1117 until a line containing a single `}' appears.
1118 With one argument the previously created group of commands for the
1119 account name is executed, and a
1121 command is executed for the system mailbox or inbox of that account.
1122 Without arguments the list of accounts and their contents are printed.
1124 .Bd -literal -offset indent
1126 set folder=imaps://mylogin@imap.myisp.example
1128 set from="myname@myisp.example (My Name)"
1129 set smtp=smtp://mylogin@smtp.myisp.example
1133 creates an account named `myisp' which can later be selected by
1134 specifying `account myisp'.
1135 The special account `null' (case-insensitive) always exists.
1137 can be used to localize account settings.
1138 Accounts can be deleted via
1141 (a) With no arguments, prints out all currently-defined aliases.
1142 With one argument, prints out that alias.
1143 With more than one argument,
1144 creates a new alias or changes an old one.
1146 can be used to delete aliases.
1148 (alt) The alternates command is useful if the user has accounts on
1150 It can be used to inform \*(UA that the listed addresses all belong to
1152 When replying to messages \*(UA will not send a copy of the message
1153 to any of the addresses listed on the alternates list.
1154 If the alternates command is given with no argument,
1155 the current set of alternate names is displayed.
1157 (ans) Takes a message list and marks each message as having been
1159 This mark has no technical meaning in the mail system;
1160 it just causes messages to be marked in the header summary,
1161 and makes them specially addressable.
1163 \*(OP Only applicable to cached IMAP mailboxes;
1164 takes a message list and reads the specified messages into the IMAP
1167 Calls a macro (see the
1174 \*(OP Only applicable to S/MIME signed messages.
1175 Takes a message list and a file name and saves the certificates
1176 contained within the message signatures to the named file in both
1177 human-readable and PEM format.
1178 The certificates can later be used to send encrypted messages to the
1179 respective message senders by setting
1180 .Va smime-encrypt-USER@HOST
1183 (ch) Changes the user's working directory to the specified one,
1184 or to the user's login directory, if none was given.
1187 Only applicable to threaded mode.
1188 Takes a message list and makes all replies to these messages invisible
1189 in header summaries,
1190 unless they are in state `new'.
1192 \*(OP (conn) If operating in disconnected mode on an IMAP mailbox,
1193 switch to online mode and connect to the mail server while retaining the
1195 See the description of the
1197 variable for more information.
1199 (c) The copy command does the same thing that
1201 does except that it does not mark the given messages for deletion when
1203 Compressed files and IMAP mailboxes are handled as described for the
1209 but saves the messages in a file named after the local part of the
1210 sender address of the first message.
1212 Print the current working directory.
1214 \*(OP (dec) For unencrypted messages,
1215 this command is identical to
1217 Encrypted messages are first decrypted, if possible, and then copied.
1219 \*OP (Dec) Similar to
1221 but saves the messages in a file named after the local part of the
1222 sender address of the first message.
1224 (def) Without arguments the current list of macros, including their
1225 content, is printed.
1226 If arguments are given this command defines a macro.
1227 A macro definition is a sequence of commands in the following form:
1228 .Bd -literal -offset indent
1237 A defined macro can be explicitly invoked using
1241 or it can be implicitly invoked by setting the
1244 .Va folder-hook-fullname
1246 Macros can be deleted via
1249 (d) Takes a list of messages as argument and marks them all as deleted.
1250 Deleted messages will not be saved in `mbox',
1251 nor will they be available for most other commands.
1256 \*(OP (disco) If operating in online mode on an IMAP mailbox,
1257 switch to disconnected mode while retaining the mailbox status.
1258 See the description of the
1261 A list of messages may optionally be given as argument;
1262 the respective messages are then read into the cache before the
1263 connection is closed.
1264 Thus `disco *' makes the entire mailbox available for disconnected use.
1265 .It Ic dp Ns \ or Ic dt
1266 Deletes the current message and prints the next message.
1267 If there is no next message, \*(UA says `at EOF'.
1269 Takes a message list and marks each given message as a draft.
1270 This mark has no technical meaning in the mail system;
1271 it just causes messages to be marked in the header summary,
1272 and makes them specially addressable.
1274 Echoes its arguments,
1275 resolving special names as documented for the command
1277 The escape sequences `\ea', `\eb', `\ec', `\ef', `\en', `\er', `\et',
1278 `\ev', `\e\e', and `\e0octal-num\fR' are interpreted just as they are by
1280 (proper quoting provided).
1282 (e) Point the text editor at each message from the given list in turn.
1283 Modified contents are discarded unless the
1292 conditional \(em if the condition of a preceeding
1294 was false, check the following condition and execute the following block
1295 if it evaluates true.
1302 conditional \(em if none of the conditions of the preceeding
1306 commands was true, the
1315 conditional execution block.
1317 (ex or x) Effects an immediate return to the Shell without modifying the
1318 user's system mailbox, his `mbox' file, or his edit file in
1320 as well as a possibly tracked command line editor history file.
1322 Print the list of features that have been compiled into \*(UA.
1327 (fl) Takes a message list and marks the messages as `flagged' for
1328 urgent/special attention.
1329 This mark has no technical meaning in the mail system;
1330 it just causes messages to be highlighted in the header summary,
1331 and makes them specially addressable.
1333 (fold) The folder command switches to a new mail file or folder.
1334 With no arguments, it tells the user which file he is currently reading.
1335 If an argument is given, it will write out changes (such as deletions)
1336 the user has made in the current file and read in the new file.
1337 Some special conventions are recognized for the
1340 .Bl -tag -offset indent -width ".Ar %:filespec"
1342 (number sign) means the previous file,
1344 (percent sign) means the invoking user's system mailbox
1349 means the system mailbox of `user'
1350 (and never the value of
1352 regardless of its actual setting),
1354 (ampersand) means the invoking user's `mbox' file (see
1358 means a `file' in the
1362 expands to the same value as `filespec',
1363 but the file is handled as a system mailbox by, e.g., the
1370 If the name matches one of the strings defined with the command
1372 it is replaced by its long form and expanded.
1373 If the name ends with `.gz', `.bz2' or `.xz' it is treated as being
1380 If `name' refers to a directory with the subdirectories `tmp', `new',
1381 and `cur', then it is treated as a folder in `maildir' format.
1384 .Dl \*(IN protocol://[user[:password]@]host[:port][/path]
1385 .Dl \*(OU protocol://[user@]host[:port][/path]
1387 is taken as an Internet mailbox specification.
1388 The \*(OPally supported protocols are `imap' (IMAP v4r1), `imaps'
1389 (IMAP with SSL/TLS encrypted transport), `pop3' (POP3) and `pop3s' (POP3
1390 with SSL/TLS encrypted transport).
1391 The `[/path]' part is valid only for IMAP; there it defaults to `INBOX'.
1393 \*(IN If `user' or `password' contain special characters, in particular
1394 whitespace, `/', `:' or `%', they must be specified in URL notation
1397 may be helpful for preparation).
1398 If no `user' is specified in the URL, the
1400 variable chain is inspected; likewise the
1402 variable chain for the password.
1404 \*(OU If `user' contains special characters, in particular `/' or `%',
1405 they must be escaped in URL notation \(en the command
1407 can be used to show the necessary conversion.
1408 The optional `path' part applies to IMAP only;
1409 if it is omitted, the default `INBOX' is used.
1411 If \*(UA is connected to an IMAP server,
1412 a name of the form `@mailbox' refers to the `mailbox' on that server,
1413 but otherwise a `@' prefix has no special meaning.
1415 With no arguments, list the names of the folders in the folder directory.
1416 With an existing folder as an argument,
1417 lists the names of folders below the named folder;
1418 e.\|g. the command `folders @' lists the folders on the base level of
1419 the current IMAP server.
1420 See also the variable
1421 .Va imap-list-depth .
1425 but saves the message in a file named after the local part of the first
1426 recipient's address.
1430 but saves the message in a file named after the local part of the first
1431 recipient's address.
1435 but responds to all recipients regardless of the
1440 .It Ic followupsender
1443 but responds to the sender only regardless of the
1449 (fwd) Takes a message and the address of a recipient
1450 and forwards the message to him.
1451 The text of the original message is included in the new one,
1452 with the value of the
1454 variable printed before.
1459 commands specify which header fields are included in the new message.
1460 Only the first part of a multipart message is included unless the
1461 .Va forward-as-attachment
1466 but saves the message in a file named after the local part of the
1467 recipient's address.
1469 (f) Takes a list of messages and prints their message headers,
1470 piped through the pager if the output does not fit on the screen.
1472 Specifies which header fields are to be ignored with the command
1474 This command has no effect when the
1475 .Va forward-as-attachment
1478 Specifies which header fields are to be retained with the command
1483 This command has no effect when the
1484 .Va forward-as-attachment
1487 Without arguments it lists all currently defined command aliases,
1489 With two arguments it defines a new command alias: the first argument is
1490 the name under which the second should be accessible.
1491 The content of the second argument can be just about anything.
1492 A ghost can be used everywhere a normal command can be used, but always
1493 takes precedence; any arguments that are given to the command alias are
1494 joined onto the alias content, and the resulting string forms the
1495 command line that is, in effect, executed.
1499 .Dl ? ghost ls '!ls -latro'
1502 (h) Lists the current range of headers, which is an 18-message group.
1503 If a `+' argument is given the next 18-message group is printed,
1504 likewise the previous is printed if the argument was `-'.
1512 the list of history entries;
1515 argument selects and shows the respective history entry \(en
1516 press `ENTER' to accept it, and the history entry will become the new
1518 The default mode if no arguments are given is
1521 (ho, also preserve) Takes a message list and marks each message therein
1522 to be saved in the user's system mailbox instead of in `mbox'.
1523 Does not override the
1526 \*(UA deviates from the POSIX standard with this command,
1529 command issued after
1531 will display the following message, not the current one.
1533 Part of the nestable
1538 conditional execution construct \(em if the given condition is false
1539 execute the following block.
1540 .Bd -literal -offset indent
1548 Note that POSIX only supports the conditions `[Rr]eceive', `[Ss]end'
1549 and `[Tt]erm' (execute if standard input is a tty).
1550 Extensions are `0' (never execute) and `1' (always execute);
1551 it is also possible to conditionalize upon wether an option is set,
1552 or set to a specific value, by using the `$' conditional trigger, e.g.:
1553 .Bd -literal -offset indent
1557 if $encoding == "UTF-8"
1560 if $encoding != "UTF-8"
1565 The first form simply checks wether an option is set, the other two also
1566 perform value content comparison (equality and non-equality,
1567 respectively); an unset value is treated as the empty string, then.
1568 The \*(OPal regular expression support adds `=~' and `!~' tests, which
1569 treat the right hand side as a regular expression, e.g., `^UTF.*' (see
1573 Add the list of header fields named to the ignored list.
1574 Header fields in the ignore list are not printed on the terminal when
1575 a message is printed.
1576 This command is very handy for suppression of certain machine-generated
1582 commands can be used to print a message in its entirety, including
1584 It lists the current set of ignored fields if no arguments were given.
1586 \*(OP Sends command strings directly to the current IMAP server.
1587 \*(UA operates always in IMAP `selected state' on the current mailbox;
1588 commands that change this will produce undesirable results and should be
1590 Useful IMAP commands are:
1591 .Bl -tag -offset indent -width ".Ic getquotearoot"
1593 Takes the name of an IMAP mailbox as an argument and creates it.
1595 (RFC 2087) Takes the name of an IMAP mailbox as an argument
1596 and prints the quotas that apply to the mailbox.
1597 Not all IMAP servers support this command.
1599 (RFC 2342) Takes no arguments and prints the Personal Namespaces,
1600 the Other User's Namespaces and the Shared Namespaces.
1601 Each namespace type is printed in parentheses;
1602 if there are multiple namespaces of the same type,
1603 inner parentheses separate them.
1604 For each namespace a prefix and a hierarchy separator is listed.
1605 Not all IMAP servers support this command.
1611 Prints the names of all available commands, alphabetically sorted.
1613 Can only be used inside of a macro definition block introduced by
1617 and is interpreted as a boolean (value `0' means false, everything
1619 Any option that had been set while `localopts' was in effect will be
1620 reverted to its former value once the block is left / the `account'
1622 .Bd -literal -offset indent
1623 define temporary_settings {
1633 Note that these options stack upon each other, i.e., if macro1 sets
1634 `localopts' and calls macro2, which explicitly resets `localopts', then
1635 any values set within macro2 will still be cleaned up by macro1.
1639 but saves the message in a file named after the local part of the first
1640 recipient's address.
1642 (m) Takes a (list of) recipient address(es) as (an) argument(s),
1643 or asks on standard input if none were given;
1644 then collects the remaining mail content and sends it out.
1646 The given message list is to be sent to `mbox' when \*(UA is quit.
1647 This is the default action unless the
1650 \*(UA deviates from the POSIX standard with this command,
1653 command issued after
1655 will display the following message, not the current one.
1664 In the former case all sources are loaded first as necessary.
1666 .Va mimetypes-load-control
1667 option can be used to fine-tune which sources are loaded.
1671 but marks the messages for deletion if they were transferred
1674 Takes a message list and invokes the
1676 on that list, printing a form-feed (`\\f') in between messages.
1680 but also prints ignored header fields and all MIME parts.
1684 but moves the messages to a file named after the local part of the
1685 sender address of the first message.
1687 Checks for new mail in the current folder without committing any changes
1689 If new mail is present, a message is printed.
1693 the headers of each new message are also printed.
1695 (n) (like `+' or `ENTER') Goes to the next message in sequence
1697 With an argument list, types the next matching message.
1708 If the current folder is located on an IMAP or POP3 server,
1709 a `NOOP' command is sent.
1710 Otherwise, no operation is performed.
1714 but also pipes ignored header fields and all parts of MIME
1715 `multipart/alternative' messages.
1717 (pi) Takes a message list and a shell command
1718 and pipes the messages through the command.
1719 Without an argument the current message is piped through the command
1726 every message is followed by a formfeed character.
1733 but also prints out ignored header fields and all parts of MIME
1734 `multipart/alternative' messages.
1741 (p) Takes a message list and types out each message on the user's
1743 If the message is a MIME multipart message,
1744 all parts with a content type of `text' or `message' are shown,
1745 the other are hidden except for their headers.
1746 Messages are decrypted and converted to the terminal character set
1749 (q) Terminates the session, saving all undeleted, unsaved messages in
1750 the current `mbox', preserving all messages marked with
1754 or never referenced in his system mailbox,
1755 and removing all other messages from his system mailbox.
1756 If new mail has arrived during the session,
1757 the message `You have new mail' is given.
1758 If given while editing a mailbox file with the command line flag
1760 then the edit file is rewritten.
1761 A return to the shell is effected,
1762 unless the rewrite of edit file fails,
1763 in which case the user can escape with the exit command.
1771 (rem) Removes the named folders.
1772 The user is asked for confirmation in interactive mode.
1774 (ren) Takes the name of an existing folder
1775 and the name for the new folder
1776 and renames the first to the second one.
1777 Both folders must be of the same type
1778 and must be located on the current server for IMAP.
1780 (R) Reply to originator.
1781 Does not reply to other recipients of the original message.
1783 (r) Takes a message list and sends mail to the sender and all recipients
1784 of the specified messages.
1785 The default message must not be deleted.
1789 but responds to all recipients regardless of the
1797 but responds to the sender only regardless of the
1805 but does not add any header lines.
1806 This is not a way to hide the sender's identity,
1807 but useful for sending a message again to the same recipients.
1809 Takes a list of messages and a user name
1810 and sends each message to the named user.
1811 `Resent-From:' and related header fields are prepended to the new copy
1822 .It Ic respondsender
1826 Add the list of header fields named to the retained list.
1827 Only the header fields in the retain list are shown on the terminal when
1828 a message is printed, all other header fields are suppressed.
1833 commands can be used to print a message in its entirety.
1834 The current set of retained fields is shown if
1836 is used without arguments.
1840 but saves the messages in a file named after the local part of the
1841 sender of the first message instead of taking a filename argument.
1843 (s) Takes a message list and a filename and appends each message in turn
1844 to the end of the file.
1845 If no filename is given, the `mbox' file is used.
1846 The filename in quotes, followed by the line count and character count
1847 is echoed on the user's terminal.
1848 If editing a system mailbox the messages are marked for deletion.
1849 Compressed files and IMAP mailboxes are handled as described for the
1851 command line option above.
1864 Header fields thus marked are filtered out when saving a message by
1866 or when automatically saving to `mbox'.
1867 This command should only be applied to header fields that do not contain
1868 information needed to decode the message,
1869 as MIME content fields do.
1870 If saving messages on an IMAP account ignoring fields makes it
1871 impossible to copy the data directly on the server,
1872 thus operation usually becomes much slower.
1882 Header fields thus marked are the only ones saved with a message when
1885 or when automatically saving to `mbox'.
1889 The use of this command is strongly discouraged since it may strip
1890 header fields that are needed to decode the message correctly.
1892 Takes a message list and marks all messages as having been read.
1894 (se) With no arguments, prints all variable values.
1895 Otherwise, sets an option.
1896 Arguments are of the form `option=value' (no space before or after `='),
1897 or plain `option' if there is no value.
1898 Quotation marks may be placed around any part of the assignment
1899 statement to quote blanks or tabs, e.g.,
1901 .Dl set indentprefix="->"
1903 If an argument begins with `no', as in `set nosave',
1904 the effect is the same as invoking the
1906 command with the remaining part of the variable (`unset save').
1910 except that the options are also exported into the program environment;
1911 since this task requires native host support the command will always
1912 report error if that is not available (but still act like
1915 This operation is a no-op unless all resource files have been loaded.
1919 (sh) Invokes an interactive version of the shell.
1921 Defines a shortcut name and its string for expansion,
1922 as described for the
1925 If used without arguments the currently defined shortcuts are printed.
1929 but performs neither MIME decoding nor decryption so that the raw
1930 message text is shown.
1932 Print the size in characters of each message of the given message-list.
1934 Create a sorted representation of the current folder,
1937 command and the addressing modes such that they refer to messages in the
1939 Message numbers are the same as in regular mode.
1943 a header summary in the new order is also printed.
1944 Possible sorting criteria are:
1945 .Bl -tag -offset indent -width "subject"
1947 Sort the messages by their `Date:' field,
1948 that is by the time they were sent.
1950 Sort messages by the value of their `From:' field,
1951 that is by the address of the sender.
1955 the sender's real name (if any) is used.
1957 Sort the messages by their size.
1959 \*(OP Sort the message by their spam score, as has been classified via
1963 Sort the messages by their message status (new, read, old, etc.).
1965 Sort the messages by their subject.
1967 Create a threaded order,
1971 Sort messages by the value of their `To:' field,
1972 that is by the address of the recipient.
1976 the recipient's real name (if any) is used.
1979 If no argument is given,
1980 the current sorting criterion is printed.
1982 The source command reads commands from a file.
1984 \*(OP Takes a list of messages and clears their `is-spam' flag.
1986 \*(OP Takes a list of messages and forces the spam detector to forget it
1987 has ever used them to train its Bayesian filter, wether as `ham' or
1990 \*(OP Takes a list of messages and teaches them to the spam detector as
1992 This also clears the `is-spam' flag of the messages in question.
1994 \*(OP Takes a list of messages and rates them using the configured spam
1995 detector, setting their `is-spam' flag as appropriate.
1996 Note that the messages are not modified, and due to that the rating will
1997 get lost once the mailbox is left.
1998 Refer to the manual section
2000 for the complete picture of spam handling in \*(UA.
2002 \*(OP Takes a list of messages and sets their `is-spam' flag.
2004 \*(OP Takes a list of messages and teaches them to the spam detector as
2006 This also sets the `is-spam' flag of the messages in question.
2008 (th) Create a threaded representation of the current folder,
2009 i.\|e. indent messages that are replies to other messages in the header
2010 display and change the
2012 command and the addressing modes such that they refer to messages in the
2014 Message numbers are the same as in unthreaded mode.
2018 a header summary in threaded order is also printed.
2020 Takes a message list and prints the top few lines of each.
2021 The number of lines printed is controlled by the variable
2023 and defaults to five.
2025 Takes a message list and marks the messages for saving in `mbox'.
2026 \*(UA deviates from the POSIX standard with this command,
2029 command issued after `mbox' will display the following message instead
2032 (T) Identical to the
2039 Delete all given accounts.
2040 An error message is printed if a given account is not defined.
2041 Attempts to delete the currently active account are rejected.
2043 Takes a list of names defined by alias commands
2044 and discards the remembered groups of users.
2046 Takes a message list and marks each message as not having been answered.
2048 (unc) Only applicable to threaded mode.
2049 Takes a message list and makes the message and all replies to it visible
2050 in header summaries again.
2051 When a message becomes the current message,
2052 it is automatically made visible.
2053 Also when a message with collapsed replies is printed,
2054 all of these are automatically uncollapsed.
2056 Undefine all given macros.
2057 An error message is printed if a given macro is not defined.
2059 (u) Takes a message list and marks each message as not being deleted.
2061 Takes a message list and
2062 .Ns un Ns Ic draft Ns
2065 Takes a message list and marks each message as not being
2068 Removes the header field names from the list of ignored fields for the
2072 Removes the header field names from the list of retained fields for the
2076 Remove an existing command
2079 Removes the header field names from the list of ignored fields.
2084 (U) Takes a message list and marks each message as not having been read.
2086 Removes the header field names from the list of retained fields.
2088 Removes the header field names from the list of ignored fields for
2091 Removes the header field names from the list of retained fields for
2094 Takes a list of option names and discards their remembered values;
2100 except that the options are also removed from the program environment;
2101 since this task requires native host support the command will always
2102 report error if that is not available (but still act like
2105 This operation is a no-op unless all resource files have been loaded.
2109 Deletes the shortcut names given as arguments.
2111 Disable sorted or threaded mode
2117 return to normal message order and,
2121 print a header summary.
2126 Decode the given URL-encoded string arguments and show the results.
2128 URL-encode the given arguments and show the results.
2130 Show information about all given options.
2132 \*(OP (verif) Takes a message list and verifies each message.
2133 If a message is not an S/MIME signed message,
2134 verification will fail for it.
2135 The verification process checks if the message was signed using a valid
2137 if the message sender's email address matches one of those contained
2138 within the certificate,
2139 and if the message content has been altered.
2141 (v) Takes a message list and invokes the display editor on each message.
2142 Modified contents are discarded unless the
2146 (w) For conventional messages the body without all headers is written.
2147 The output is decrypted and converted to its native format as necessary.
2148 If the output file exists, the text is appended.
2149 If a message is in MIME multipart format its first part is written to
2150 the specified file as for conventional messages,
2151 and the user is asked for a filename to save each other part.
2152 For convience saving of each part may be skipped by giving an empty value;
2153 the same result can also be achieved by writing it to
2155 For the second and subsequent parts a leading `|' character causes the
2156 part to be piped to the remainder of the user input interpreted as
2158 otherwise the user input is expanded as usually for folders,
2159 e.g., tilde expansion is performed.
2160 In non-interactive mode, only the parts of the multipart message
2161 that have a filename given in the part header are written,
2162 the others are discarded.
2163 The original message is never marked for deletion in the originating
2166 the contents of the destination file are overwritten if the file
2168 No special handling of compressed files is performed.
2173 \*(UA presents message headers in windowfuls as described under the
2176 This command scrolls to the next window of messages.
2177 If an argument is given,
2178 it specifies the window to use.
2179 A number prefixed by `+' or `\-' indicates
2180 that the window is calculated in relation to the current position.
2181 A number without a prefix specifies an absolute window number,
2182 and a `$' lets \*(UA scroll to the last window of messages.
2186 but scrolls to the next or previous window that contains at least one
2187 new or `flagged' message.
2191 .\" .Ss "Tilde escapes" {{{
2193 Here is a summary of the tilde escapes,
2194 which are used to perform special functions when composing messages.
2195 Tilde escapes are only recognized at the beginning of lines.
2196 The name `tilde escape' is somewhat of a misnomer since the actual
2197 escape character can be set by the option
2199 .Bl -tag -width ".Ic ~< filename"
2201 Insert the string of text in the message prefaced by a single `~'.
2202 (If the escape character has been changed,
2203 that character must be doubled
2204 in order to send it at the beginning of a line.)
2205 .It Ic ~! Ar command
2206 Execute the indicated shell
2208 then return to the message.
2210 Same effect as typing the end-of-file character.
2211 .It Ic ~: Ar \*(UA-command Ns \ or Ic ~_ Ar \*(UA-command
2212 Execute the given \*(UA command.
2213 Not all commands, however, are allowed.
2215 Write a summary of command escapes.
2216 .It Ic ~< Ar filename
2219 .It Ic ~<! Ar command
2221 is executed using the shell.
2222 Its standard output is inserted into the message.
2223 .It Ic ~@ Op Ar filename...
2224 With no arguments, edit the attachment list interactively.
2225 If an attachment's file name is left empty,
2226 that attachment is deleted from the list.
2227 When the end of the attachment list is reached,
2228 \*(UA will ask for further attachments until an empty name is given.
2229 If a given file name solely consists of the number sign `#' followed
2230 by a valid message number of the currently active mailbox, the given
2231 message is attached as a MIME `message/rfc822' and the rest of this
2232 section does not apply.
2234 If character set conversion has been compiled into \*(UA, then this mode
2235 gives the user the option to specify input and output character sets,
2236 unless the file extension indicates binary content, in which case \*(UA
2237 asks wether this step shall be skipped for the attachment in question.
2238 If not skipped, then the charset that succeeds to represent the
2239 attachment data will be used in the `charset=' MIME parameter of the
2243 If input and output character sets are specified, then the conversion is
2244 performed on the fly.
2245 The user will be asked repeatedly until the desired conversion succeeds.
2247 If only an output character set is specified, then the input is assumed
2250 charset and will be converted to the given output charset on the fly.
2251 The user will be asked repeatedly until the desired conversion succeeds.
2253 If no character sets are specified at all then the algorithm that is
2254 documented in the section
2255 .Sx "Character sets"
2256 is applied, but directly and on the fly.
2257 The user will be asked repeatedly until the desired conversion succeeds.
2259 Finally, if an input-, but no output character set is specified, then no
2260 conversion is ever performed, but the `charset=' MIME parameter will
2261 still be set to the user input.
2263 The character set selection loop can be left by typing `control-C',
2264 i.e., causing an interrupt.
2265 .\" \*(OU next sentence
2266 Note that before \*(UA version 15.0 this terminates the entire
2267 current attachment selection, not only the character set selection.
2270 Without character set conversion support, \*(UA will ask for the input
2271 character set only, and it'll set the `charset=' MIME parameter to the
2272 given input, if any;
2273 if no user input is seen then the
2275 character set will be used for the `charset=' parameter instead.
2276 Note that the file extension check isn't performed in this mode, since
2277 no conversion will take place anyway.
2279 Note that in non-interactive mode, for reproduceabilities sake, there
2280 will always be two questions for each attachment, regardless of wether
2281 character set conversion is available and what the file extension is.
2282 The first asks for the filename, and the second asks for the input
2283 character set to be passed through to the `charset=' MIME parameter;
2284 no conversion will be tried if there is input to the latter question,
2285 otherwise the usual conversion algorithm, as above, is applied.
2286 For message attachments, the answer to the second question is completely
2291 arguments are specified,
2292 they are treated as a comma separated list of files,
2293 which are all expanded and appended to the end of the attachment list.
2294 (Filenames with commas, or with leading or trailing whitespace can only
2295 be added via the command line or the first method.
2296 Message attachments can only be added via the first method;
2297 filenames which clash with message numbers can only be added via the
2298 command line or the second method.)
2299 In this mode the (text) attachments are assumed to be in
2301 encoding, and will be evaluated as documented in the section
2302 .Sx "Character sets" .
2304 Inserts the string contained in the
2306 variable (same as `~i Sign').
2307 The escape sequences `\et' (tabulator) and `\en' (newline) are understood.
2309 Inserts the string contained in the
2311 variable (same as `~i sign').
2312 The escape sequences `\et' (tabulator) and `\en' (newline) are understood.
2313 .It Ic ~b Ar name ...
2314 Add the given names to the list of blind carbon copy recipients.
2315 .It Ic ~c Ar name ...
2316 Add the given names to the list of carbon copy recipients.
2318 Read the file specified by the
2320 variable into the message.
2322 Invoke the text editor on the message collected so far.
2323 After the editing session is finished,
2324 the user may continue appending text to the message.
2325 .It Ic ~F Ar messages
2326 Read the named messages into the message being sent, including all
2327 message headers and MIME parts.
2328 If no messages are specified, read in the current message.
2329 .It Ic ~f Ar messages
2330 Read the named messages into the message being sent.
2331 If no messages are specified, read in the current message.
2332 Message headers currently being ignored (by the
2336 command) are not included.
2337 For MIME multipart messages,
2338 only the first printable part is included.
2340 Edit the message header fields `From:', `Reply-To:', `Sender:' and
2341 `Organization:' by typing each one in turn and allowing the user to edit
2343 The default values for these fields originate from the
2351 Edit the message header fields `To:', `Cc:', `Bcc:', and `Subject:' by
2352 typing each one in turn and allowing the user to edit the field.
2353 .It Ic ~i Ar variable
2354 Insert the value of the specified variable into the message,
2355 adding a newline character at the end.
2356 The message remains unaltered if the variable is unset or empty.
2357 The escape sequences `\et' (tabulator) and `\en' (newline) are understood.
2358 .It Ic ~M Ar messages
2359 Read the named messages into the message being sent,
2362 If no messages are specified, read the current message.
2363 .It Ic ~m Ar messages
2364 Read the named messages into the message being sent,
2367 If no messages are specified, read the current message.
2368 Message headers currently being ignored (by the
2372 commands) are not included.
2373 For MIME multipart messages,
2374 only the first printable part is included.
2376 Print out the message collected so far,
2377 prefaced by the message header fields
2378 and followed by the attachment list, if any.
2380 Abort the message being sent,
2381 copying it to the file specified by the
2386 .It Ic ~R Ar filename
2387 Read the named file into the message, indented by
2389 .It Ic ~r Ar filename
2390 Read the named file into the message.
2392 Cause the named string to become the current subject field.
2393 .It Ic ~t Ar name ...
2394 Add the given name(s) to the direct recipient list.
2395 .It Ic ~U Ar messages
2396 Like `~m', but exclude all message headers.
2397 .It Ic ~u Ar messages
2398 Like `~f', but exclude all message headers.
2400 Invoke an alternate editor (defined by the
2402 option) on the message collected so far.
2403 Usually, the alternate editor will be a screen editor.
2404 After the editor is quit,
2405 the user may resume appending text to the end of the message.
2406 .It Ic ~w Ar filename
2407 Write the message onto the named file.
2409 the message is appended to it.
2411 Same as `~q', except that the message is not saved at all.
2412 .It Ic ~| Ar command
2413 Pipe the message through the specified filter command.
2414 If the command gives no output or terminates abnormally,
2415 retain the original text of the message.
2418 is often used as a rejustifying filter.
2422 .\" .Ss "Variable options" {{{
2423 .Ss "Variable options"
2424 Options are controlled via
2428 commands, see the corresponding entries for a syntax description.
2429 An option is also set if it is passed to \*(UA as part of the program
2430 environment (this is not restricted to specific variables as in the
2432 A value given in a startup file overrides a value imported from the
2434 Options may be either binary, in which case it is only significant to
2435 see whether they are set or not;
2436 or string, in which case the actual value is of interest.
2439 .\" .Ss "Binary options" {{{
2440 .Ss "Binary options"
2441 The binary options include the following:
2442 .Bl -tag -width ".Va autoprint"
2443 .It Va add-file-recipients
2444 When file or pipe recipients have been specified,
2445 mention them in the corresponding address fields of the message instead
2446 of silently stripping them from their recipient list.
2447 By default such addressees are not mentioned.
2449 Causes only the local part to be evaluated
2450 when comparing addresses.
2452 Causes messages saved in mbox to be appended to the end rather than
2454 This should always be set.
2455 .It Va ask Ns \ or Va asksub
2456 Causes \*(UA to prompt for the subject of each message sent.
2457 If the user responds with simply a newline,
2458 no subject field will be sent.
2460 Causes the prompts for `Cc:' and `Bcc:' lists to appear after the
2461 message has been edited.
2463 If set, \*(UA asks for files to attach at the end of each message.
2464 An empty line finalizes the list.
2466 Causes the user to be prompted for additional carbon copy recipients (at
2467 the end of each message if
2472 An empty line finalizes the list.
2474 Causes the user to be prompted for additional blind carbon copy
2475 recipients (at the end of each message if
2480 An empty line finalizes the list.
2482 \*(OP Causes the user to be prompted if the message is to be signed at
2483 the end of each message.
2486 variable is ignored when this variable is set.
2488 Causes threads to be collapsed automatically when threaded mode is
2493 Causes the delete command to behave like `dp -';
2494 thus, after deleting a message the next one will be typed automatically.
2496 Causes threaded mode (see the
2498 command) to be entered automatically when a folder is opened.
2500 Enables the substitution of `!' by the contents of the last command line
2502 .It Va batch-exit-on-error
2503 If the batch mode has been enabled via the
2505 command line option, then this variable will be consulted whenever \*(UA
2506 completes one operation (returns to the command prompt); if it is set
2507 then \*(UA will terminate if the last operation generated an error.
2509 Causes automatic display of a header summary after executing a
2513 Sets some cosmetical features to traditional BSD style;
2514 has the same affect as setting
2516 and all other variables prefixed with `bsd';
2517 it also changes the meaning of the \*(UA specific `\\&'
2521 Changes the letters printed in the first column of a header summary
2522 to traditional BSD style.
2524 Changes the display of columns in a header summary to traditional BSD
2527 Changes some informational messages to traditional BSD style.
2529 Causes the `Subject:' field to appear immediately after the `To:' field
2530 in message headers and with the `~h' tilde command.
2532 Changes the output format of the
2534 command to traditional BSD style.
2535 .It Va colour-disable
2536 \*(OP Forcefully disable usage of colours.
2537 Also see the section
2538 .Sx "Coloured message display" .
2540 Prints debugging messages and disables the actual delivery of messages.
2543 this option is intended for \*(UA development only.
2545 \*(OP When an IMAP mailbox is selected and this variable is set,
2546 no connection to the server is initiated.
2547 Instead, data is obtained from the local cache (see
2550 Mailboxes that are not present in the cache
2551 and messages that have not yet entirely been fetched from the server
2553 to fetch all messages in a mailbox at once,
2555 .Ns ` Ns Li copy * /dev/null Ns '
2556 can be used while still in
2559 Changes that are made to IMAP mailboxes in disconnected mode are queued
2560 and committed later when a connection to that server is opened in online
2562 This procedure is not completely reliable since it cannot be guaranteed
2563 that the IMAP unique identifiers (UIDs) on the server still match the
2564 ones in the cache at that time.
2567 when this problem occurs.
2568 .It Va disconnected-USER@HOST
2569 The specified account is handled as described for the
2572 but other accounts are not affected.
2574 The binary option dot causes \*(UA to interpret a period alone on a line
2575 as the terminator of a message the user is sending.
2577 If this variable is set then the editor is started automatically when
2578 composing a message in an interactive mode,
2579 as if the `~e' tilde command had been specified.
2582 variable is implied for this automatically spawned editor session.
2584 When a message is edited while being composed,
2585 its header is included in the editable text.
2586 The `To:', `Cc:', `Bcc:', `Subject:', `From:', `Reply-To:', `Sender:',
2587 and 'Organization:' fields are accepted within the header,
2588 other fields are ignored.
2590 If set, an empty mailbox file is not removed.
2591 This may improve the interoperability with other mail user agents
2592 when using a common folder directory.
2594 If the mailbox is empty \*(UA normally prints `No mail for user' and
2596 If this option is set \*(UA starts even with an empty mailbox.
2602 commands and vice-versa.
2603 .It Va forward-as-attachment
2604 Original messages are normally sent as inline text with the
2607 and only the first part of a multipart message is included.
2608 With this option messages are sent as MIME `message/rfc822' attachments
2609 with all of their parts included.
2614 options are ignored when the
2615 .Va forward-as-attachment
2618 When replying to a message \*(UA normally removes the comment parts of
2620 which by convention contain the full names of the recipients.
2621 If this variable is set such stripping is not performed,
2622 and comments are retained.
2624 Causes the header summary to be written at startup and after commands
2625 that affect the number of messages or the order of messages in the
2626 current folder; enabled by default.
2627 The command line option
2632 This option is used to hold messages in the system mailbox by default.
2634 \*(OP Can be used to turn off the automatic conversion of domain names
2635 according to the rules of IDNA (internationalized domain names for
2637 Since the IDNA code assumes domain names are specified with the
2639 character set, an UTF-8 locale charset is required to represent
2640 all possible international domain names (before conversion, that is).
2642 Ignore interrupt signals from the terminal while entering messages;
2643 instead echo them as `@' characters and discard the current line.
2645 An option related to
2649 which makes \*(UA refuse to accept a `control-D' as the end of a message.
2650 This option also applies to \*(UA command mode.
2651 .It Va imap-use-starttls
2652 \*(OP Causes \*(UA to issue a `STARTTLS' command to make an unencrypted
2653 IMAP session SSL/TLS encrypted.
2654 This functionality is not supported by all servers,
2655 and is not used if the session is already encrypted by the IMAPS method.
2656 .It Va imap-use-starttls-USER@HOST
2658 .Va imap-use-starttls
2659 for a specific account.
2661 This option causes \*(UA to truncate the user's system mailbox instead
2662 of deleting it when it is empty.
2663 This should always be set since it prevents malicious users from
2664 creating fake mail folders in a world-writable spool directory.
2666 When a message is saved it is usually discarded from the originating
2667 folder when \*(UA is quit.
2668 Setting this option causes all saved message to be retained.
2669 .It Va line-editor-disable
2670 Turn off any enhanced command line editing capabilities (see
2671 .Sx "Command line editor"
2674 When a message is replied to and this variable is set,
2675 it is marked as having been answered.
2676 This mark has no technical meaning in the mail system;
2677 it just causes messages to be marked in the header summary,
2678 and makes them specially addressable.
2679 .It Va message-id-disable
2680 By setting this option the generation of `Message-ID:' can be completely
2681 suppressed, effectively leaving this task up to the mail-transfer-agent
2682 (MTA) or the SMTP server.
2683 (According to RFC 5321 your SMTP server is not required to add this
2684 field by itself, so you should ensure that it accepts messages without
2687 Usually, when a group is expanded that contains the sender,
2688 the sender is removed from the expansion.
2689 Setting this option causes the sender to be included in the group.
2690 .It Va mime-allow-text-controls
2691 When sending messages, each part of the message is MIME-inspected in
2692 order to classify the `Content-Type:' and `Content-Transfer-Encoding:'
2693 that is required to send this part over mail transport, i.e.,
2694 a computation rather similar to what the
2696 command produces when used with the
2700 This classification however treats text files which are encoded in
2701 UTF-16 (often found for HTML files) and similar character sets as binary
2702 octet-streams, forcefully changing any `text/plain' or `text/html'
2703 specification to `application/octet-stream';
2704 if that actually happens, then a yet unset charset MIME parameter is set
2705 to `binary', effectively making it impossible for the receiving MUA to
2706 automatically interpret the contents of the part.
2708 If this option is set, and the data was unambiguously identified as text
2709 data at first glance (by a `.txt' or `.html' file extension), then the
2710 original `Content-Type:' will not be overwritten.
2711 .It Va mime-counter-evidence
2712 Normally the `Content-Type:' field is used to decide how to treat
2713 a messages MIME part.
2714 Some MUAs however don't use
2716 or a similar mechanism to correctly classify content,
2717 but simply specify `application/octet-stream',
2718 even for plain text attachments like `text/diff'.
2719 If this variable is set then \*(UA will use the file extension of
2720 attachments to classify such MIME message parts, if possible.
2722 Causes the filename given in the
2725 and the sender-based filenames for the
2729 commands to be interpreted relative to the directory given in the
2731 variable rather than to the current directory,
2732 unless it is set to an absolute pathname.
2734 If set, each message the
2736 command prints out is followed by a formfeed character.
2738 Send messages to the
2740 command without performing MIME and character set conversions.
2741 .It Va pop3-bulk-load
2742 \*(OP When accessing a POP3 server \*(UA loads the headers of the
2743 messages, and only requests the message bodies on user request.
2744 For the POP3 protocol this means that the message headers will be
2746 If this option is set then \*(UA will download only complete messages
2747 from POP3 servers instead.
2750 a macro that temporarily sets this option, then accesses a POP3 account
2751 that is known to only get small text messages, and then unsets this
2754 \*(OP Unless this variable is set the `APOP' authentication method
2755 will be used when connecting to a POP3 server that advertises support.
2756 The advantage of APOP over `USER/PASS' authentication is that the
2757 password is not sent in clear text over the wire and that only a single
2758 packet is sent for the user/password tuple.
2759 .It Va pop3-no-apop-HOST
2760 \*(IN Disables the `APOP' authentication method for a specific host.
2761 .It Va pop3-no-apop-USER@HOST
2762 Disables the `APOP' authentication method for a specific account.
2763 .It Va pop3-use-starttls
2764 \*(OP Causes \*(UA to issue a `STLS' command to make an unencrypted POP3
2765 session SSL/TLS encrypted.
2766 This functionality is not supported by all servers,
2767 and is not used if the session is already encrypted by the POP3S method.
2768 .It Va pop3-use-starttls-HOST
2770 .Va pop3-use-starttls
2771 for a specific host.
2772 .It Va pop3-use-starttls-USER@HOST
2774 .Va pop3-use-starttls
2775 for a specific account.
2776 .It Va print-all-chars
2777 This option causes all characters to be considered printable.
2778 It is only effective if given in a startup file.
2779 With this option set some character sequences in messages may put the
2780 user's terminal in an undefined state when printed;
2781 it should only be used as a last resort if no working system locale can
2783 .It Va print-alternatives
2784 When a MIME message part of type `multipart/alternative' is displayed
2785 and it contains a subpart of type `text/plain',
2786 other parts are normally discarded.
2787 Setting this variable causes all subparts to be displayed,
2788 just as if the surrounding part was of type `multipart/mixed'.
2790 Suppresses the printing of the version when first invoked.
2791 .It Va quote-as-attachment
2792 If this is set, then the original message is added in its entirety
2793 as a `message/rfc822' MIME attachment when replying to a message.
2794 Note this works regardless of the setting of
2796 .It Va recipients-in-cc
2797 On group replies, specify only the sender of the original mail in `To:'
2798 and mention it's other recipients in the secondary `Cc:'.
2799 .It Va record-resent
2800 If both this variable and the
2807 commands save messages to the
2809 folder as it is normally only done for newly composed messages.
2810 .It Va reply-in-same-charset
2811 If this variable is set \*(UA first tries to use the same character set
2812 of the original message for replies.
2813 If this fails, the mechanism described in
2814 .Sx "Character sets"
2815 is evaluated as usual.
2817 Reverses the sense of
2822 .It Va rfc822-body-from_
2823 This variable can be used to force the display of a so-called `From_'
2824 line for messages that are embedded into an envelope mail via the
2825 `message/rfc822' MIME mechanism.
2827 When the user aborts a message with two `RUBOUT' (interrupt,
2828 `control-C') characters,
2829 \*(UA will copy the partial letter to the file
2831 This option is set by default.
2832 .It Va searchheaders
2833 Expand message-list specifiers in the form `/x:y' to all messages
2834 containing the substring `y' in the header field `x'.
2835 The string search is case insensitive.
2836 .It Va sendcharsets-else-ttycharset
2837 \*(OP If this variable is set, but
2839 is not, then \*(UA acts as if
2841 had been set to the value of the variable
2843 In effect this combination passes through the message data in the
2844 character set of the current locale (given that
2846 hasn't been set manually), i.e., without converting it to the
2848 fallback character set.
2849 Thus, mail message text will be in `ISO-8859-1' encoding when send from
2850 within a `ISO-8859-1' locale, and in `UTF-8' encoding when send from
2851 within an `UTF-8' locale.
2852 If no character set conversion capabilities are available in \*(UA then
2853 the only supported character set is
2856 When sending a message wait until the MTA exits before accepting further
2858 If the MTA returns a non-zero exit status,
2859 the exit status of \*(ua will also be non-zero.
2861 Setting this option causes \*(UA to start at the last message instead of
2862 the first one when opening a mail folder.
2864 Causes \*(UA to use the sender's real name instead of the plain address
2865 in the header field summary and in message specifications.
2867 Causes the recipient of the message to be shown in the header summary
2868 if the message was sent by the user.
2869 .It Va skipemptybody
2870 If an outgoing message does not contain any text in its first or only
2872 do not send it but discard it silently (see also the command line option
2875 .It Va smime-force-encryption
2876 \*(OP Causes \*(UA to refuse sending unencrypted messages.
2878 \*(OP S/MIME sign outgoing messages with the user's private key and
2879 include the user's certificate as a MIME attachment.
2880 Signing a message enables a recipient to verify that the sender used
2881 a valid certificate,
2882 that the email addresses in the certificate match those in the message
2883 header and that the message content has not been altered.
2884 It does not change the message text,
2885 and people will be able to read the message as usual.
2889 .Va smime-sign-include-certs .
2890 .It Va smime-no-default-ca
2891 \*(OP Don't load default CA locations when verifying S/MIME signed
2893 .It Va smtp-use-starttls
2894 \*(OP Causes \*(UA to issue a `STARTTLS' command to make an SMTP session
2896 Not all servers support this command \(en because of common
2897 implementation defects it can't be automatically determined whether
2898 a server supports it or not.
2899 .It Va ssl-no-default-ca
2900 \*(OP Don't load default CA locations to verify SSL/TLS server
2903 \*(OP Accept SSLv2 connections.
2904 These are normally not allowed because this protocol version is insecure.
2905 .It Va keep-content-length
2906 When (editing messages and) writing MBOX mailbox files \*(UA can be told
2907 to keep the `Content-Length:' and `Lines:' header fields that some MUAs
2908 generate by setting this variable.
2909 Since \*(UA does neither use nor update these non-standardized header
2910 fields (which in itself shows one of their conceptual problems),
2911 stripping them should increase interoperability in between MUAs that
2912 work with with same mailbox files.
2913 Note that, if this is not set but
2914 .Va writebackedited ,
2915 as below, is, a possibly performed automatic stripping of these header
2916 fields already marks the message as being modified.
2918 Setting this option enables upward compatibility with \*(UA version 15.0
2919 in respect to which configuration options are available and how they are
2921 This manual uses \*(IN and \*(OU to refer to the new and the old way of
2922 doing things, respectively.
2924 Setting this option, also controllable via the command line option
2926 causes \*(UA to be more verbose, so that, e.g., certificate chains will
2927 be displayed on the users terminal.
2928 Setting this binary options twice increases the level of verbosity, in
2929 which case even details of the actual message delivery and protocol
2930 conversations are also shown.
2933 is sufficient to disable verbosity as such.
2934 .It Va writebackedited
2935 If this variable is set messages modified using the
2939 commands are written back to the current folder when it is quit;
2940 it is only honoured for writable folders in `mbox' format, though.
2941 Note that the editor will be pointed to the raw message content in that
2942 case, i.e., neither MIME decoding nor decryption will have been
2944 and proper RFC 4155 `From ' quoting of newly added or edited content is
2945 also left as an excercise to the user.
2949 .\" .Ss "Value options" {{{
2951 The value options include the following:
2952 .Bl -tag -width ".Va autoprint"
2954 A sequence of characters to print in the `attribute' column of a header
2956 each for one type of messages in the following order:
2957 new (N), unread but old (U), new but read (R), read and old (O), saved
2958 (S), preserved (P), mboxed (M), flagged (F), answered (A), draft (T),
2959 start of a collapsed thread (+), collapsed (\-), classified as spam ($).
2960 The default is `NUROSPMFAT+\-$',
2961 or `NU\ \ *HMFAT+\-$' if
2965 environment variable are set.
2967 Specifies a list of recipients to which a blind carbon copy of each
2968 outgoing message will be sent automatically.
2970 Specifies a list of recipients to which a carbon copy of each outgoing
2971 message will be sent automatically.
2973 Causes sorted mode (see the
2975 command) to be entered automatically with the value of this option as
2976 sorting method when a folder is opened.
2978 The value that should appear in the `charset=' parameter of
2979 `Content-Type:' MIME header fields when no character set conversion of
2980 the message data was performed.
2981 This defaults to `US-ASCII', and the chosen character set should be
2982 `US-ASCII' compatible.
2984 \*(OP The default 8 bit character set that is used as an implied last
2985 member of the variable
2987 Defaults to `UTF-8'.
2988 If no character set conversion capabilities are available in \*(UA then
2989 the only supported character set is
2991 Refer to the section
2992 .Sx "Character sets"
2993 for the complete picture of character set conversion in \*(UA.
2995 The default value for the
2999 \*(OP The colour specification for so-called `From_' lines.
3001 .Sx "Coloured message display"
3002 for the format of the value.
3003 .It Va colour-header
3004 \*(OP The colour specification for header lines.
3006 .Sx "Coloured message display"
3007 for the format of the value.
3008 .It Va colour-msginfo
3009 \*(OP The colour specification for the introductional message info line.
3011 .Sx "Coloured message display"
3012 for the format of the value.
3013 .It Va colour-pagers
3014 \*(OP A comma-separated list of
3016 s for which coloured message display can be used.
3017 Note that only a substring comparison is performed, meaning that the
3018 string `lesser' will match the string `less'.
3020 .Sx "Coloured message display"
3022 The default is set to the sole string `less'.
3023 .It Va colour-partinfo
3024 \*(OP The colour specification for MIME part info lines.
3026 .Sx "Coloured message display"
3027 for the format of the value.
3029 \*(OP A comma-separated list of
3031 inals for which coloured message display can be used.
3034 .Dl cons25,linux,rxvt,rxvt-unicode,\:screen,\:sun,\:vt100,\:vt220,\:\
3035 wsvt25,\:xterm,\:xterm-color
3036 .It Va colour-uheader
3037 \*(OP The colour specification for those header lines that have been
3039 .Va colour-user-headers
3042 .Sx "Coloured message display"
3043 for the format of the value.
3044 .It Va colour-user-headers
3045 A comma separated list of (case-insensitive) header names which should
3046 be colourized with the alternative
3049 The default value is `from,subject'.
3051 The valued option crt is used as a threshold to determine how long
3052 a message must be before
3057 is set without a value then the height of the terminal screen stored in
3058 the system is used to compute the threshold (see
3064 The name of the file to use for saving aborted messages.
3065 This defaults to `dead.letter' in the user's home directory.
3067 The date in a header summary is normally the date of the mailbox `From\ '
3068 line of the message.
3069 If this variable is set, then the date as given in the `Date:' field is
3070 used, converted to local time.
3071 It is possible to control the display of the date by assigning a value,
3074 function will be used to format the date accordingly.
3075 Please read your system manual for the available formats.
3076 Note that the `%n' format should not be used, because \*(UA doesn't
3077 take embedded newlines into account when calculating how many lines fit
3079 .It Va datefield-markout-older
3080 This option, when set in addition to
3082 modifies the display of messages that are not really current in a way
3083 that is rather comparable to the
3088 The interpretation of the value is identical to what has been described
3092 Pathname of the text editor to use in the
3097 A default editor is used if this value is not defined.
3099 Suggestion for the MIME encoding to use in outgoing text messages
3101 Valid values are the default `quoted-printable', `8bit' and `base64'.
3102 `8bit' may cause problems with when transferring mail messages over
3103 channels that are not ESMTP (RFC 1869) compliant.
3104 If there is no need to encode a message,
3105 `7bit' transfer mode is always used regardless of this variable.
3106 Binary data is always encoded as `base64'.
3108 If defined, the first character of this option
3109 gives the character to use in place of `~' to denote tilde escapes.
3111 The name of the directory to use for storing folders of messages.
3112 All folder names that begin with `+' refer to files below it.
3113 The same special conventions as documented for the
3115 command may be used when specifying a new value for
3117 but be aware that the expansion is fully performed immediately.
3118 E.g., if the expanded name refers to an IMAP account, all names that
3119 begin with `+' refer to IMAP mailboxes below the
3123 Note: some IMAP servers do not accept the creation of mailboxes in
3124 the hierarchy base, but require that they are created as subfolders of
3125 `INBOX' \(en with such servers a folder name of the form
3127 .Dl imaps://mylogin@imap.myisp.example/INBOX.
3129 should be used (the last character is the server's hierarchy delimiter).
3130 Folder names prefixed by `+' will then refer to folders below `INBOX',
3131 while folder names prefixed by `@' refer to folders below the hierarchy
3135 namespace command for a method to detect the appropriate prefix and
3138 When a folder is opened and this variable is set,
3139 the macro corresponding to the value of this variable is executed.
3140 The macro is also invoked when new mail arrives,
3141 but message lists for commands executed from the macro
3142 only include newly arrived messages then.
3143 .It Va folder-hook-fullname
3144 When a folder named `fullname' is opened,
3145 the macro corresponding to the value of this variable is executed.
3146 Unlike other folder specifications,
3147 the fully expanded name of a folder, without metacharacters,
3148 is used to avoid ambiguities.
3149 The macro specified with
3151 is not executed if this variable is effective for a folder
3154 ed from within the actually executed macro).
3156 The address (or a list of addresses) to put into the `From:' field of
3157 the message header, quoting RFC 5322:
3158 the author(s) of the message, that is, the mailbox(es) of the person(s)
3159 or system(s) responsible for the writing of the message.
3160 If replying to messages these addresses are handled as if they were in
3164 If the machine's hostname is not valid at the Internet (for example at
3165 a dialup machine) then either this variable or
3170 adds even more fine-tuning capabilities),
3174 contains more than one address,
3177 variable is required (according to the standard RFC 5322).
3179 The string to print before the text of a message with the
3183 .Va forward-as-attachment
3185 Defaults to `-------- Original Message --------' if unset.
3186 No heading is printed if it is set to the empty string.
3188 A format string to use for the header summary,
3192 A `%' character introduces a format specifier.
3193 It may be followed by a number indicating the field width.
3194 If the (possibly implicitly implied) field width is negative, the field
3195 is to be left-aligned.
3196 Valid format specifiers are:
3197 .Bl -tag -offset indent -width "%%"
3201 The date when the message was received.
3203 The indenting level in threaded mode.
3205 The address of the message sender.
3207 The message thread structure.
3208 (Note that this format doesn't support a field width.)
3210 The number of lines of the message.
3214 The number of octets (bytes) in the message.
3216 Message subject (if any).
3218 Message subject (if any) in double quotes.
3220 The position in threaded/sorted order.
3222 A `>' for the current message, otherwise ` '.
3224 A `<' for the current message, otherwise ` '.
3226 The spam score of the message, as has been classified via the command
3232 The default is `%>\&%a\&%m\ %-18f\ %16d\ %4l/%\-5o\ %i%-s',
3233 or `%>\&%a\&%m\ %20-f\ \ %16d\ %3l/%\-5o\ %i%-S' if
3238 .It Va headline-bidi
3239 Bidirectional text requires special treatment when displaying headers,
3240 because numbers (in dates or for file sizes etc.) will not affect the
3241 current text direction, in effect resulting in ugly line layouts when
3242 arabic or other right-to-left text is to be displayed.
3243 On the other hand only a minority of terminals is capable to correctly
3244 handle direction changes, so that user interaction is necessary for
3246 Note that extended host system support is required nonetheless, e.g.,
3247 detection of the terminal character set is one precondition;
3248 and this feature only works in an Unicode (i.e., UTF-8) locale.
3250 In general setting this variable will cause \*(UA to encapsulate text
3251 fields that may occur when printing
3253 with special Unicode control sequences;
3254 it is possible to fine-tune the terminal support level by assigning
3256 no value (or any value other than `1', `2' and `3') will make \*(UA
3257 assume that the terminal is capable to properly deal with Unicode
3258 version 6.3, in which case text is embedded in a pair of U+2068 (FIRST
3259 STRONG ISOLATE) and U+2069 (POP DIRECTIONAL ISOLATE) characters.
3260 In addition no space on the line is reserved for these characters.
3262 Weaker support is chosen by using the value `1' (Unicode 6.3, but
3263 reserve the room of two spaces for writing the control sequences onto
3265 The values `2' and `3' select Unicode 1.1 support (U+200E, LEFT-TO-RIGHT
3266 MARK); the latter again reserves room for two spaces in addition.
3268 Use this string as hostname when expanding local addresses instead of
3269 the value obtained from
3273 i.e., in `Message-ID:' and `From:' fields.
3276 transport is not used then it is normally the responsibility of the MTA
3277 to create these fields, \*(IN in conjunction with
3281 also influences the results;
3282 you should produce some test messages with the desired combination of
3289 \*(OP Sets the IMAP authentication method.
3290 Valid values are `login' for the usual password-based authentication
3292 `cram-md5', which is a password-based authentication that does not send
3293 the password over the network in clear text,
3294 and `gssapi' for GSS-API based authentication.
3295 .It Va imap-auth-USER@HOST
3296 Sets the IMAP authentication method for a specific account.
3298 \*(OP Enables caching of IMAP mailboxes.
3299 The value of this variable must point to a directory that is either
3300 existent or can be created by \*(UA.
3301 All contents of the cache can be deleted by \*(UA at any time;
3302 it is not safe to make assumptions about them.
3303 .It Va imap-keepalive
3304 \*(OP IMAP servers may close the connection after a period of
3305 inactivity; the standard requires this to be at least 30 minutes,
3306 but practical experience may vary.
3307 Setting this variable to a numeric `value' greater than 0 causes
3308 a `NOOP' command to be sent each `value' seconds if no other operation
3310 .It Va imap-list-depth
3311 \*(OP When retrieving the list of folders on an IMAP server, the
3313 command stops after it has reached a certain depth to avoid possible
3315 The value of this variable sets the maximum depth allowed.
3317 If the folder separator on the current IMAP server is a slash `/',
3318 this variable has no effect and the
3320 command does not descend to subfolders.
3322 String used by the `~m', `~M' and `~R' tilde escapes and by the
3324 option for indenting messages,
3325 in place of the normal tabulator character (`^I'), which is the default.
3326 Be sure to quote the value if it contains spaces or tabs.
3328 Pathname of the directory lister to use in the
3330 command when operating on local mailboxes.
3333 .It Va line-editor-cursor-right
3334 \*(OP If the builtin command line editor is used, actions which are
3335 based on rightwise movement may not work on some terminals.
3336 If you encounter such problems, set this variable to the terminal
3337 control sequence that is necessary to move the cursor one column to the
3339 The default is `\\033[C', which should work for most terminals.
3340 Less often occur `\\033OC' and `\\014'.
3341 Note that `ESCAPE' and other control character have to be written as
3342 shell-style escape sequences, e.g., `\\033' for `ESCAPE'.
3344 Is used as the user's mailbox, if set.
3345 Otherwise, a system-dependent default is used.
3346 Supports a logical subset of the special conventions that are documented
3353 The name of the mbox file.
3354 Supports a logical subset of the special conventions that are documented
3360 The fallback default is `mbox' in the user's home directory.
3361 .It Va mimetypes-load-control
3362 This option can be used to control which of the
3364 MIME type databases are loaded by \*(UA.
3365 If the letter `u' (or `U') is part of this options value, then the
3368 file will be loaded (if it exists);
3369 likewise the letter `s' (or `S') controls loading of the system wide
3370 .Pa /etc/mime.types .
3371 If this option is not set \*(UA will try to load both files instead.
3372 Incorporation of the MIME types that are compiled into \*(UA cannot be
3374 .It Va NAIL_EXTRA_RC
3375 The name of an optional startup file to be read after \*(ur.
3376 This variable is ignored if it is imported from the environment;
3377 it has an effect only if it is set in \*(UR or \*(ur to allow bypassing
3378 the configuration with, e.g., `MAILRC=/dev/null'.
3379 Use this file for commands that are not understood by other \*(UA
3382 A string to put at the beginning of each new message.
3383 The escape sequences `\et' (tabulator) and `\en' (newline) are understood.
3384 .It Va NAIL_HISTFILE
3385 \*(OP If a command line editor is available then this can be set to
3386 name the (expandable) path of the location of a permanent history file.
3387 .It Va NAIL_HISTSIZE
3388 \*(OP If a command line editor is available this value restricts the
3389 amount of history entries that are saved into a set and valid
3391 A value of less than 0 disables this feature;
3392 note that loading and incorporation of
3394 upon program startup can also be suppressed by doing this.
3395 An unset or invalid value, or 0, causes a default value to be used.
3396 Dependent on the available command line editor this will also define the
3397 number of history entries in memory;
3398 it is also editor-specific wether runtime updates of this value will be
3401 A string to put at the end of each new message.
3402 The escape sequences `\et' (tabulator) and `\en' (newline) are understood.
3404 If this variable has the value `maildir',
3405 newly created local folders will be in `maildir' format.
3407 Checks for new mail in the current folder each time the prompt is
3409 For IMAP mailboxes the server is then polled for new mail,
3410 which may result in delayed operation if the connection to the server is
3412 A `maildir' folder must be re-scanned to determine if new mail has
3415 If this variable is set to the special value `nopoll' an IMAP server is
3416 not actively asked for new mail,
3417 but new mail may still be detected and announced with any other IMAP
3418 command that is sent to the server.
3419 A `maildir' folder is not scanned, then.
3421 In either case the IMAP server may send notifications about messages
3422 that have been deleted on the server by another process or client.
3423 In this case, `Expunged X messages' is printed regardless of this
3425 and message numbers may have changed.
3427 The value to put into the `Organization:' field of the message header.
3429 Pathname of the program to use in the more command or when the
3432 The default paginator is
3435 \*(IN Sets a global fallback password, which is used in case none has
3436 been given in the protocol and account-specific URL and neither is there
3437 a matching `password-USER@HOST' nor a matching `password-HOST';
3438 as a last resort \*(UA will ask for a password on the user's terminal if
3439 the authentication method requires a password.
3440 Specifying passwords in a startup file is generally a security risk;
3441 the file should be readable by the invoking user only.
3442 .It Va password-HOST
3445 for accounts on a specific host.
3446 .It Va password-USER@HOST
3451 for a specific account.
3453 Set the password for `user' when connecting to `host'.
3454 If no such variable is defined for a host,
3455 the user will be asked for a password on standard input.
3456 Specifying passwords in a startup file is generally a security risk;
3457 the file should be readable by the invoking user only.
3458 .It Va pipe-content/subcontent
3459 When a MIME message part of `content/subcontent' type is displayed or
3461 its text is filtered through the value of this variable interpreted as
3464 The special value `@' can be used to force interpretation of the message
3465 part as plain text, e.g., `set pipe-application/pgp-signature=@' will
3466 henceforth treat signatures as plain text and display them "as is".
3468 Also, if a normal shell command is prefixed with `@', then the command
3469 will only be used to prepare the MIME message part if the message is
3470 displayed by itself, but not when multiple messages are displayed at
3473 Finally, if a normal shell command is prefixed with `@&', then, in
3474 addition to what has been described for the plain `@' shell command
3475 prefix, the command will be run asynchronously, i.e., without blocking
3476 \*(UA, which may be a handy way to display a, e.g., PDF file while also
3477 continuing to read the mail message.
3479 Special care must be taken when using such commands as mail viruses may
3480 be distributed by this method;
3481 if messages of type `application/x-sh' were filtered through the shell,
3483 a message sender could easily execute arbitrary code on the system \*(UA
3485 .It Va pop3-keepalive
3486 \*(OP POP3 servers close the connection after a period of inactivity;
3487 the standard requires this to be at least 10 minutes,
3488 but practical experience may vary.
3489 Setting this variable to a numeric `value' greater than 0 causes
3490 a `NOOP' command to be sent each `value' seconds if no other operation
3493 The string printed when a command is accepted.
3494 Prompting may be prevented by either setting this to the null string
3497 The same XSI escape sequences that are understood by the
3499 command may be used within
3502 In addition, the following \*(UA specific additional sequences are
3504 `\\&', which expands to `?' unless
3506 is set, in which case it expands to `&';
3507 note that "\\& " is the default value for
3509 `\\?', which will expand to `1' if the last command failed, and to `0'
3511 `\\$', which will expand to the name of the currently active
3513 if any, and to the empty string otherwise,
3514 and `\\@', which will expand to the name of the currently active mailbox.
3515 (Note that the prompt buffer is size-limited, excess is cut off.)
3517 When a newer version of the
3519 .Sx "Command line editor"
3520 is used, any escape sequence must itself be encapsulated with another
3521 escape character for usage with the
3523 mechanism: \*(UA configures the control character `\\01' for this.
3525 If set, \*(UA starts a replying message with the original message
3526 prefixed by the value of the variable
3528 Normally, a heading consisting of `Fromheaderfield wrote:' is printed
3529 before the quotation.
3530 If the string `noheading' is assigned to the
3532 variable, this heading is omitted.
3533 If the string `headers' is assigned, the headers selected by the
3534 .Ic ignore Ns / Ns Ic retain
3535 commands are printed above the message body,
3538 acts like an automatic `~m' tilde escape command, then.
3539 If the string `allheaders' is assigned, all headers are printed above
3540 the message body and all MIME parts are included,
3543 act like an automatic `~M' command.
3545 .Va quote-as-attachment .
3547 \*(OP Can be set in addition to
3549 Setting this turns on a more fancy quotation algorithm in that leading
3550 quotation characters are compressed and overlong lines are folded.
3552 can be set to either one or two (space separated) numeric values,
3553 which are interpreted as the maximum (goal) and the minimum line length,
3554 respectively, in a spirit rather equal to the
3556 program, but line-, not paragraph-based.
3557 If not set explicitly the minimum will reflect the goal algorithmically.
3558 The goal can't be smaller than the length of
3560 plus some additional pad.
3561 Necessary adjustments take place silently.
3563 If defined, gives the pathname of the folder used to record all outgoing
3565 If not defined, then outgoing mail is not saved.
3566 When saving to this folder fails the message is not sent,
3567 but instead saved to
3570 A list of addresses to put into the `Reply-To:' field of the message
3572 Members of this list are handled as if they were in the
3576 When \*(UA initially prints the message headers it determines the number
3577 to print by looking at the speed of the terminal.
3578 The faster the terminal, the more it prints.
3579 This option overrides this calculation and specifies how many message
3580 headers are printed.
3581 This number is also used for scrolling with the
3585 \*(OP A comma-separated list of character set names that can be used in
3586 outgoing Internet mail.
3587 The value of the variable
3589 is automatically appended to this list of character-sets.
3590 If no character set conversion capabilities are compiled into \*(UA then
3591 the only supported charset is
3594 .Va sendcharsets-else-ttycharset
3595 and refer to the section
3596 .Sx "Character sets"
3597 for the complete picture of character set conversion in \*(UA.
3599 An address that is put into the `Sender:' field of outgoing messages,
3600 quoting RFC 5322: the mailbox of the agent responsible for the actual
3601 transmission of the message.
3602 This field should normally not be used unless the `From:' field contains
3603 more than one address, on which case it is required.
3606 address is handled as if it were in the
3610 To use an alternate mail delivery system,
3611 set this option to the full pathname of the program to use.
3612 It may be necessary to set
3613 .Va sendmail-progname
3615 .It Va sendmail-progname
3616 Many systems use a so-called
3618 environment to ensure compatibility with
3620 This works by inspecting the name that was used to invoke the mail
3622 If this variable is set then the mailwrapper (the program that is
3623 actually executed when calling `sendmail') will treat its contents as
3625 The default is `sendmail'.
3627 Pathname of the shell to use in the
3629 command and the `~!' tilde escape.
3630 A default shell is used if this option is not defined.
3632 A string for use with the `~A' tilde escape.
3634 A string for use with the `~a' tilde escape.
3636 Must correspond to the name of a readable file if set.
3637 The file's content is then appended to each singlepart message
3638 and to the first part of each multipart message.
3639 Be warned that there is no possibility to edit the signature for an
3642 \*(OP Specifies a directory with CA certificates in PEM (Privacy
3643 Enhanced Mail) format for verification of S/MIME signed messages.
3644 .It Va smime-ca-file
3645 \*(OP Specifies a file with CA certificates in PEM format for
3646 verification of S/MIME signed messages.
3647 .It Va smime-cipher-USER@HOST
3648 \*(OP Specifies a cipher to use when generating S/MIME encrypted
3649 messages for the specified account.
3650 RFC 5751 mandates a default of `aes-128' (AES-128 CBC).
3652 The actually available cipher algorithms depend on the cryptographic
3653 library that \*(UA uses; possible values are, in decreasing cipher
3655 `aes-256' (AES-256 CBC), `aes-192' (AES-192 CBC), `aes-128' (AES-128 CBC),
3656 `des3' (DES EDE3 CBC, 168 bits; default if `aes-128' isn't available)
3657 and `des' (DES CBC, 56 bits).
3659 The following ciphers have been obsoleted and are no longer mentioned by
3660 the S/MIME specification (RFC 5751), but may be selected if available:
3661 `rc2-64' (RC2 CBC, 64 bits) and `rc2-40' (RC2 CBC, 40 bits).
3662 .It Va smime-crl-file
3663 \*(OP Specifies a file that contains a CRL in PEM format to use when
3664 verifying S/MIME messages.
3665 .It Va smime-crl-dir
3666 \*(OP Specifies a directory that contains files with CRLs in PEM format
3667 to use when verifying S/MIME messages.
3668 .It Va smime-encrypt-USER@HOST
3669 \*(OP If this variable is set, messages send to the given receiver are
3670 encrypted before sending.
3671 The value of the variable must be set to the name of a file that
3672 contains a certificate in PEM format.
3674 If a message is sent to multiple recipients,
3675 each of them for whom a corresponding variable is set will receive an
3676 individually encrypted message;
3677 other recipients will continue to receive the message in plain text
3679 .Va smime-force-encryption
3681 It is recommended to sign encrypted messages, i.e., to also set the
3684 .It Va smime-sign-cert
3685 \*(OP Points to a file in PEM format.
3686 For the purpose of signing and decryption this file needs to contain the
3687 user's private key as well as his certificate.
3689 For the purpose of encryption the recipient's public encryption key
3690 (certificate) is expected; the command
3692 can be used to save certificates of signed messages (the section
3693 .Sx "Signed and encrypted messages with S/MIME"
3694 gives some details).
3695 This mode of operation is usually driven via
3696 .Va smime-sign-cert-USER@HOST ,
3698 .It Va smime-sign-cert-USER@HOST
3701 for a specific account.
3702 For message signing `USER@HOST' is always derived from the value of
3704 (or, if that contains multiple addresses,
3708 When decrypting messages the account is derived from the recipient
3709 fields (`To:' and `Cc:') of the message, which are searched for
3710 addresses for which such a variable is set.
3711 \*(UA always uses the first address that matches,
3712 so if the same message is sent to more than one of the user's addresses
3713 using different encryption keys, decryption might fail.
3714 .It Va smime-sign-include-certs
3715 \*(OP If used, this is supposed to a consist of a comma-separated list
3716 of files, each of which containing a single certificate in PEM format to
3717 be included in the S/MIME message in addition to the
3720 This is most useful for long certificate chains if it is desired to aid
3721 the receiving party's verification process.
3722 Note that top level certificates may also be included in the chain but
3723 don't play a role for verification.
3727 .Va smime-sign-cert-USER@HOST .
3728 .It Va smime-sign-include-certs-USER@HOST
3730 .Va smime-sign-include-certs
3731 for a specific account.
3733 \*(OP Normally \*(UA invokes the program defined via
3735 to transfer messages.
3738 variable will instead cause `SMTP' network connections be made to the
3739 server specified therein in order to directly submit the message.
3740 \*(UA knows about three different "SMTP protocols":
3741 .Bl -bullet -offset indent
3743 The plain `SMTP' protocol (RFC 5321) that normally lives on the
3744 server port 25 and requires setting of the
3745 .Va smtp-use-starttls
3746 variable as above to enter a SSL/TLS encrypted session state.
3747 Assign a value like \*(IN `[smtp://][user[:password]@]server[:port]'
3748 (\*(OU `[smtp://]server[:port]')
3749 to choose this protocol.
3751 Then the so-called `SMTPS' which is supposed to live on server port 465
3752 and is automatically SSL/TLS secured.
3753 Unfortunately it never became a standardized protocol and may thus not
3754 be supported by your hosts network service database
3755 \(en in fact the port number has already been reassigned to other
3758 `SMTPS' is nonetheless a commonly offered "protocol" and thus can be
3759 chosen by assigning a value like \*(IN
3760 `smtps://[user[:password]@]server[:port]'
3761 (\*(OU `smtps://server[:port]');
3762 due to the mentioned problems it is usually necessary to explicitly
3763 specify the port as `:465', however.
3765 Finally there is the `SUBMISSION' protocol (RFC 6409), which usually
3766 lives on server port 587 and is practically identically to the `SMTP'
3767 protocol from \*(UAs point of view beside that; it requires setting the
3768 .Va smtp-use-starttls
3769 variable to enter a SSL/TLS secured session state.
3770 Assign a value like \*(IN `submission://[user[:password]@]server[:port]'
3771 (\*(OU `submission://server[:port]').
3774 \*(IN If `user' or `password' contain special characters, in particular
3775 whitespace, `/', `:' or `%', they must be specified in URL notation
3778 may be helpful for preparation).
3780 The SMTP transfer is executed in a child process, which runs
3781 asynchronously unless either the
3786 If it receives a TERM signal, it will abort and save the message to
3789 \*(OP Sets the SMTP authentication method.
3790 Possible values are `none' (the default), `plain', `login'
3791 as well as the \*(OPal methods `cram-md5' and `gssapi'.
3792 The `none' method doesn't need any user credentials,
3793 `gssapi' requires a user name
3794 and all other methods require a user name and a password.
3801 .Va smtp-auth-password
3803 .Va smtp-auth-user Ns
3805 .It Va smtp-auth-HOST
3808 for SMTP accounts on a specific host.
3809 .It Va smtp-auth-USER@HOST
3812 for a specific account.
3813 (\*(OU For specific values of sender addresses, dependend upon the variable
3816 .It Va smtp-auth-password
3817 \*(OP \*(OU Sets the global fallback password for SMTP authentication.
3818 If the authentication method requires a password, but neither
3819 .Va smtp-auth-password
3821 .Va smtp-auth-password-USER@HOST
3823 \*(UA will ask for a password on the user's terminal.
3824 .It Va smtp-auth-password-USER@HOST
3826 .Va smtp-auth-password
3827 for specific values of sender addresses, dependent upon the variable
3829 .It Va smtp-auth-user
3830 \*(OP \*(OU Sets the global fallback user name for SMTP authentication.
3831 If the authentication method requires a user name, but neither
3834 .Va smtp-auth-user-USER@HOST
3836 \*(UA will ask for a user name on the user's terminal.
3837 .It Va smtp-auth-user-USER@HOST
3840 for specific values of sender addresses, dependent upon the variable
3842 .It Va smtp-hostname
3843 \*(IN Normally \*(UA uses the variable
3845 to derive the necessary `USER@HOST' information to issue a
3846 `MAIL FROM:<>' SMTP command.
3849 can be used to use the `USER' from the SMTP account
3854 and the `HOST' from the content of this variable
3855 (or, if that is the empty string,
3857 or the local hostname as a last resort).
3858 Setting this variable also influences the generated `Message-Id:'.
3860 \*(OP The path to the spam detector.
3861 Note that the path is not expanded, but used "as is".
3862 A fallback path will have been compiled into the \*(UA binary if the
3864 executable had been found during compilation.
3866 \*(OP Can be used to specify the host on which
3868 listens for connections; if not set, defaults to `localhost'.
3870 \*(OP Spam detectors like
3872 decline to work with messages which exceed a specific size;
3873 if this variable is set then \*(UA won't even try to pass messages which
3874 exceed the given limit.
3875 The default is 420000 bytes.
3877 \*(OP Can be used to explicitly specify the port on which
3879 listens for connections.
3881 \*(OP If the spam detector listens on a path-based UNIX domain socket,
3882 then setting this variable to the fully qualified path will force its
3883 usage for communication.
3885 \*(OP This can be used to support multiple, per-used configuration files
3886 of the spam detector.
3887 Note that \*(UA doesn't automatically set this to reflect a possibly set
3891 \*(OP Specifies a directory with CA certificates in PEM (Pricacy
3892 Enhanced Mail) for verification of of SSL/TLS server certificates.
3894 .Xr SSL_CTX_load_verify_locations 3
3895 for more information.
3897 \*(OP Specifies a file with CA certificates in PEM format for
3898 verification of SSL/TLS server certificates.
3900 .Xr SSL_CTX_load_verify_locations 3
3901 for more information.
3903 \*(OP Sets the file name for a SSL/TLS client certificate required by
3905 .It Va ssl-cert-USER@HOST
3906 Sets an account-specific file name for a SSL/TLS client certificate
3907 required by some servers.
3910 for the specified account.
3911 .It Va ssl-cipher-list
3912 \*(OP Specifies a list of ciphers for SSL/TLS connections.
3915 for more information.
3917 \*(OP Specifies a file that contains a CRL in PEM format to use when
3918 verifying SSL/TLS server certificates.
3920 \*(OP Specifies a directory that contains files with CRLs in PEM format
3921 to use when verifying SSL/TLS server certificates.
3923 \*(OP Sets the file name for the private key of a SSL/TLS client
3925 If unset, the name of the certificate file is used.
3926 The file is expected to be in PEM format.
3927 .It Va ssl-key-USER@HOST
3928 Sets an account-specific file name for the private key of a SSL/TLS
3932 for the specified account.
3934 \*(OP Selects the used TLS/SSL protocol version.
3935 The actually available protocol versions depend on the TLS/SSL
3936 library that \*(UA uses; possible values are, from newest to oldest:
3937 `tls1.2', `tls1.1', `tls1', `ssl3' and `ssl2'.
3941 to any of these values will fixate the used protocol, which means that
3942 connections will fail if the server doesn't support it.
3943 The value `auto', which is the default, chooses a compatibility method
3944 that automatically uses the newest protocol version that the server
3945 is capable to understand.
3947 It has to be noted that `auto' is used as a fallback method if
3948 the actual setting of
3950 isn't supported by the used TLS/SSL library \(em in this case an error
3951 message will be printed first, however.
3952 .It Va ssl-method-USER@HOST
3955 for a specific account.
3957 \*(OP Gives the pathname to an entropy daemon socket, see
3959 .It Va ssl-rand-file
3960 \*(OP Gives the pathname to a file with entropy data, see
3961 .Xr RAND_load_file 3 .
3962 If the file is a regular file writable by the invoking user,
3963 new data is written to it after it has been loaded.
3965 \*(OP Sets the action to be performed if an error occurs during SSL/TLS
3966 server certificate validation.
3968 `strict' (fail and close connection immediately),
3969 `ask' (ask whether to continue on standard input),
3970 `warn' (print a warning and continue),
3971 `ignore' (do not perform validation).
3972 The default is `ask'.
3973 .It Va ssl-verify-USER@HOST
3976 for a specific account.
3978 If only set without an assigned value, then this option inhibits the
3979 generation of the `Message-Id:' and `User-Agent:' header fields that
3980 include obvious references to \*(UA.
3981 There are two pitfalls associated with this:
3982 First, the message id of outgoing messages is not known anymore.
3983 Second, an expert may still use the remaining information in the header
3984 to track down the originating mail user agent.
3985 If set to the value `noagent', then the mentioned `Message-Id:'
3986 suppression doesn't occur.
3988 If defined, gives the number of lines of a message to be printed out
3989 with the top command;
3990 normally, the first five lines are printed.
3992 The character set of the terminal \*(UA operates on,
3993 and the one and only supported character set that \*(UA can use if no
3994 character set conversion capabilities have been compiled into it,
3995 in which case it defaults to `ISO-8859-1' unless it can deduce a value
3996 from the `LC_CTYPE' locale environment.
3997 Refer to the section
3998 .Sx "Character sets"
3999 for the complete picture about character sets.
4001 \*(IN Sets a global fallback user name, which is used in case none has
4002 been given in the protocol and account-specific URL and there is also
4005 This variable defaults to the value of
4010 for a specific host.
4012 Pathname of the text editor to use in the
4014 command and `~v' tilde escape.
4018 .\" .Sh ENVIRONMENT {{{
4020 Besides the variables described above,
4021 \*(UA uses the following environment variables:
4022 .Bl -tag -width ".It Va MAILRC"
4024 The user's preferred width in column positions for the terminal screen
4025 or window (only used during startup).
4027 The user's home directory.
4028 .It Va LANG , Va LC_ALL , Va LC_COLLATE , Va LC_CTYPE , Va LC_MESSAGES
4032 The user's preferred number of lines on a page or the vertical screen or
4033 window size in lines (only used during startup).
4035 Is used as a startup file instead of \*(ur if set.
4036 When \*(UA scripts are invoked on behalf of other users,
4037 this variable should be set to
4039 to avoid side-effects from reading their configuration files.
4041 If this variable is set and
4043 is not, it is treated as a startup configuration file and read.
4044 .It Va NAIL_NO_SYSTEM_RC
4045 If this variable is set then reading of \*(UR at startup is inhibited,
4046 i.e., the same effect is achieved as if \*(UA had been started up with
4050 Changes the letters printed in the first column of a header summary.
4052 \*(OP The terminal type for which output is to be prepared.
4054 Used as directory for temporary files instead of
4058 Can be used to force identification as
4060 i.e., identical to the
4062 command line option.
4068 .Bl -tag -width ".It Pa /etc/mime.types"
4070 File giving initial commands.
4072 System wide initialization file.
4073 .It Pa ~/.mime.types
4074 Personal MIME types.
4075 .It Pa /etc/mime.types
4076 System wide MIME types.
4080 .\" .Sh EXAMPLES {{{
4083 .\" .Ss "Getting started" {{{
4084 .Ss "Getting started"
4085 The \*(UA command has two distinct usages, according to whether one
4086 wants to send or receive mail.
4087 Sending mail is simple: to send a message to a user whose email address
4088 is, say, `<bill@host.example>', use the shell command:
4090 .Dl $ \*(ua bill@host.example
4092 then type your message.
4093 \*(UA will prompt you for a message `Subject:' first;
4094 after that, lines typed by you form the body of the message.
4095 When you reach the end of the message,
4096 type an EOT (`control\-D') at the beginning of a line,
4097 which will cause \*(UA to echo `EOT' and return you to the shell.
4099 If, while you are composing the message you decide that you do not wish
4100 to send it after all, you can abort the letter by typing two `RUBOUT'
4101 (interrupt, `control-C') characters.
4102 Typing a single `RUBOUT' causes \*(UA to print
4103 .Ns ` Ns Li (Interrupt -- one more to kill letter) Ns '.
4104 Typing a second `RUBOUT' causes \*(UA to save your partial letter on the
4107 and abort the letter.
4108 Once you have sent mail to someone, there is no way to undo the act, so
4111 If you want to send the same message to several other people,
4112 you can list their email addresses on the command line.
4113 .Bd -literal -offset indent
4114 $ \*(ua sam@workstation.example bob@server.example
4116 Tuition fees are due next Friday. Don't forget!
4122 will sendout to `<sam@workstation.example>' and `<bob@server.example>'.
4123 To read your mail, simply type
4127 \*(UA will respond by typing its version number and date and then
4128 listing the messages you have waiting.
4129 Then it will type a prompt and await your command.
4130 The messages are assigned numbers starting with 1 \(en you refer to the
4131 messages with these numbers.
4132 \*(UA keeps track of which messages are `new' (have been sent since you
4133 last read your mail) and `read' (have been read by you).
4134 New messages have an `N' next to them in the header listing and old,
4135 but unread messages have a `U' next to them.
4136 \*(UA keeps track of new/old and read/unread messages by putting a
4137 header field called `Status' into your messages.
4139 To look at a specific message, use the
4141 command, which may be abbreviated to simply `t'.
4142 For example, if you had the following messages:
4143 .Bd -literal -offset indent
4144 O 1 drfoo@myhost.example Wed Sep 1 19:52 5/421 "Fees"
4145 O 2 sam@friends.example Thu Sep 2 00:08 30/895
4148 you could examine the first message by giving the command:
4152 which might cause \*(UA to respond with, for example:
4153 .Bd -literal -offset indent
4154 [-- Message 1 -- 5 lines, 421 bytes --]:
4155 From drfoo@myhost.example Wed Sep 1 19:52:25 2004
4159 Tuition fees are due next Wednesday. Don't forget!
4162 Many \*(UA commands that operate on messages take a message number as an
4163 argument, just as the shown
4166 For these commands, there is a notion of a current message.
4167 When you enter the \*(UA program,
4168 the current message is initially the first (or the first recent) one.
4169 Thus, you can often omit the message number and use, for example, `t` to
4170 type the current message.
4171 As a further shorthand, you can type a message by simply giving its
4172 message number \(en hence `1` would type the first message.
4174 Frequently, it is useful to read the messages in your mailbox in order,
4176 You can read the next message in \*(UA by simply typing a newline.
4177 As a special case, you can type a newline as your first command to
4178 \*(UA to type the first message.
4180 If, after typing a message, you wish to immediately send a reply,
4181 you can do so with the command
4185 takes a message number as an argument.
4186 \*(UA then begins a message addressed to the user who sent you the
4187 message and let you type in your letter in reply, followed by
4188 a `<control-D>' at the beginning of a line, as before.
4190 Note that \*(UA copies the subject header from the original message.
4191 This is useful in that correspondence about a particular matter will
4192 tend to retain the same subject heading, making it easy to recognize.
4193 If there are other header fields in the message, like `Cc:',
4194 the information found will also be used.
4196 Sometimes you will receive a message that has been sent to several
4197 people and wish to reply only to the person who sent it.
4199 (with a capital `R') replies to a message, but sends a copy to the
4202 If you wish, while reading your mail, to send a message to someone,
4203 but not as a reply to one of your messages, you can send the message
4206 command, which takes as arguments the names of the recipients you wish
4208 For example, to send a message to `<frank@machine.example>':
4210 .Dl mail frank@machine.example
4212 To delete a message from the mail folder, you can use the command
4214 In addition to not saving deleted messages,
4215 \*(UA will not let you type them, either.
4216 The effect is to make the message disappear altogether, along with its
4219 Many features of \*(UA can be tailored to your liking with the
4221 command; it has two forms, depending on whether you are setting
4222 a `binary' or a `valued' option.
4223 Binary options are either on or off \(en for example, the
4225 option informs \*(UA that each time you send a message, you want it to
4226 prompt you for a `Cc:' header to be included in the message.
4229 option, you would type
4233 Valued options are values which \*(UA uses to adapt to your tastes.
4236 option tells \*(UA where to save messages sent by you,
4237 and is specified by, e.g.,
4241 Note that no spaces are allowed in `set record=Sent'.
4243 \*(UA includes a simple facility for maintaining groups of messages
4244 together in folders.
4245 To use the folder facility, you must tell \*(UA where you wish to keep
4247 Each folder of messages will be a single file.
4248 For convenience, all of your folders are kept in a single directory of
4250 To tell \*(UA where your folder directory is, put a line of the form
4252 .Dl set folder=letters
4255 If, as in the example above, your folder directory does not begin with
4256 a `/', \*(UA will assume that your folder directory is to be found
4257 starting from your home directory.
4259 Anywhere a file name is expected, you can use a folder name, preceded
4261 For example, to put a message into a folder with the
4263 command, you can use:
4267 to save the current message in the `classwork' folder.
4268 If the `classwork' folder does not yet exist, it will be created.
4269 Note that messages which are saved with the
4271 command are automatically removed from your system mailbox.
4273 In order to make a copy of a message in a folder without causing
4274 that message to be removed from your system mailbox, use the
4276 command, which is identical in all other respects to the
4283 can be used to direct \*(UA to the contents of a different folder.
4286 .Dl folder +classwork
4288 directs \*(UA to read the contents of the `classwork' folder.
4289 All of the commands that you can use on your system mailbox are also
4290 applicable to folders, including
4295 To inquire which folder you are currently editing, use `folder' without
4297 And to list your current set of folders, use the
4303 command is available to print out a brief summary of the most important
4306 While typing in a message to be sent to others it is often useful to be
4307 able to invoke the text editor on the partial message, print the
4308 message, execute a shell command, or do some other auxiliary function.
4309 \*(UA provides these capabilities through `tilde escapes',
4310 which consist of a tilde (`~') at the beginning of a line, followed by
4311 a single character which indicates the function to be performed.
4312 For example, to print the text of the message so far, use:
4316 which will print a line of dashes, the recipients of your message, and
4317 the text of the message so far.
4318 A list of the most important tilde escapes is available with `~?'.
4321 .\" .Ss "IMAP or POP3 client setup" {{{
4322 .Ss "IMAP or POP3 client setup"
4323 \*(OP First you need the following data from your ISP:
4324 the host name of the IMAP or POP3 server,
4325 user name and password for this server,
4326 and a notice whether the server uses SSL/TLS encryption.
4327 Assuming the SSL/TLS secured host name of your IMAP account is
4328 `server.myisp.example' and your user name for that server is `mylogin',
4329 you could refer to this account using the
4333 command line option with
4335 .Dl imaps://mylogin@server.myisp.example
4337 (This string is not necessarily the same as your Internet mail address.)
4338 Even if the server does not accept IMAPS or POP3S connections,
4339 it is possible that it supports the `STARTTLS' method of upgrading
4340 already connected, but not yet authenticated sessions to use SSL/TLS
4342 The only reliable method to see if this works is to try it; enter one of
4344 .Dl set imap-use-starttls
4345 .Dl set pop3-use-starttls
4347 before you initiate the connection, dependent on the actual protocol.
4349 As you probably want messages to be deleted from this account
4350 after saving them, prefix it with `%:'.
4353 command can be used to avoid typing that many characters every time you
4356 .Dl shortcut myisp %:imaps://mylogin@server.myisp.example
4358 You might want to put this string into a startup file.
4360 is one of those commands that are specific to \*(UA and will thus
4361 confuse other implementations of POSIX
4363 so it should possibly not be placed in \*(ur.
4366 .Dl set NAIL_EXTRA_RC=.\*(uarc
4368 in \*(ur and create a file
4370 containing all the commands that are specific to \*(UA.
4371 You can then access your remote mailbox by invoking
4375 on the command line, or by executing
4380 If you want to use more than one IMAP mailbox on a server,
4381 or if you want to use the IMAP server for mail storage too, the
4383 command (which is also \*(UA-specific) is possibly more appropriate.
4384 You can put the following in
4386 .Bd -literal -offset indent
4388 set folder=imaps://mylogin@server.myisp.example
4389 set record=+Sent MBOX=+mbox outfolder
4393 and can then access incoming mail for this account by invoking
4394 `\*(ua \-A myisp' on the command line or by executing `ac myisp' within
4396 After that, a command like `copy 1 +otherfolder' will refer to
4397 `otherfolder' on the IMAP server.
4398 In particular, `fi&' will change to the `mbox' folder,
4399 and `fi+Sent' will show your recorded sent mail,
4400 with both folders located on the IMAP server.
4402 \*(UA will ask you for a password string each time you connect to
4404 If you can reasonably trust the security of your workstation,
4405 you can give this password in the startup file as
4407 .Dl set password-mylogin@server.myisp.example="SECRET"
4409 You should change the permissions of this file to 0600, see
4412 \*(UA supports different authentication methods for both IMAP and POP3.
4413 If Kerberos is used at your location,
4414 you can try to activate (the optional) GSS-API based authentication via
4416 .Dl set imap-auth=gssapi
4418 The advantage of this method is that \*(UA doesn't need to know your
4419 password at all, nor does it have to send sensitive data over the network.
4420 If that isn't possible, try to use authentication methods that at least
4421 avoid sending the password in clear over the wire, which is especially
4422 important if SSL/TLS cannot be used, e.g.,
4424 .Dl set imap-auth=cram-md5
4426 For POP3 \*(UA will try to use the `APOP' mechanism automatically unless
4427 explicitly disabled.
4428 If the server does not offer any such authentication methods,
4429 conventional user/password based authentication must be used.
4430 It is sometimes helpful, especially when setting up an account or when
4431 there are authentification problems, to enable verbosity by setting the
4433 option \(en \*(UA will display all data sent to the server in clear text
4434 on the screen when this option is set.
4435 (Because this may also include passwords you should take care that no
4436 unauthorized person can look at your terminal when this option is set.)
4438 If you regularly use the same workstation to access IMAP accounts,
4439 you can greatly enhance performance by enabling local caching of IMAP
4441 For any message that has been fully or partially fetched from the server,
4442 a local copy is made and is used when the message is accessed again,
4443 so most data is transferred over the network once only.
4444 To enable the IMAP cache, select a local directory name and put
4446 .Dl set imap-cache=~/localdirectory
4448 in the (\*(UA-specific) startup file.
4449 All files within that directory can be overwritten or deleted by \*(UA
4451 so you should not use the directory to store other information.
4453 Once the cache contains some messages,
4454 it is not strictly necessary anymore to open a connection to the IMAP
4455 server to access them.
4456 When \*(UA is invoked with the option
4461 only cached data is used for any folder you open.
4462 Messages that have not yet been completely cached are not available
4463 then, but all other messages can be handled as usual.
4464 Changes made to IMAP mailboxes in
4466 mode are committed to the IMAP server next time it is used in
4469 Synchronizing the local status with the status on the server is thus
4470 partially within your responsibility;
4471 if you forget to initiate a connection to the server again before you
4472 leave your location,
4473 changes made on one workstation are not available on others.
4474 Also if you alter IMAP mailboxes from a workstation while uncommitted
4475 changes are still pending on another,
4476 the latter data may become invalid.
4477 The same might also happen because of internal server status changes.
4478 You should thus carefully evaluate this feature in your environment
4479 before you rely on it.
4481 Many servers will close the connection after a short period of
4482 inactivity \(en use one of
4484 .Dl set pop3-keepalive=30
4485 .Dl set imap-keepalive=240
4487 to send a keepalive message each 30 seconds for POP3,
4488 or each 4 minutes for IMAP.
4490 If you encounter problems connecting to a SSL/TLS server,
4495 variables (see the OpenSSL FAQ for more information) or specify the
4496 protocol version with
4498 Contact your ISP if you need a client certificate or if verification of
4499 the server certificate fails.
4500 If the failed certificate is indeed valid,
4501 fetch its CA certificate by executing the shell command
4503 .Dl $ </dev/null openssl s_client \-showcerts \-connect \e
4504 .Dl \ \ \ \ \ \ server.myisp.example:imaps 2>&1 | tee log.txt
4508 ) and put it into the file specified with
4510 The data you need is located at the end of the certificate chain
4511 within (and including) the `BEGIN CERTIFICATE'
4512 and `END CERTIFICATE' lines.
4513 Note that the example above is \fBinsecure\fR!
4514 One should use the `-verify' and `-CAfile' options of
4516 to be "on the safe side" regarding the fetched certificates.
4519 .\" .Ss "Reading HTML mail" {{{
4520 .Ss "Reading HTML mail"
4525 utility or another command-line web browser that can write plain text to
4528 .Dl set pipe-text/html="elinks -force-html -dump 1"
4529 .Dl set pipe-text/html="lynx -stdin -dump -force_html"
4531 will cause HTML message parts to be converted into a more friendly form.
4534 .\" .Ss "Viewing PDF attachments" {{{
4535 .Ss "Viewing PDF attachments"
4536 Most PDF viewers do not accept input directly from a pipe.
4537 It is thus necessary to store the attachment in a temporary file first:
4539 .Dl set pipe-application/pdf="@&cat >/tmp/\*(ua$$.pdf; \e
4540 .Dl \ \ \ \ \ \ acroread /tmp/\*(ua$$.pdf; rm /tmp/\*(ua$$.pdf"
4542 Note that security defects are discovered in PDF viewers from time to
4544 Automatical command execution like this can compromise your system
4546 in particular if you stay not always informed about such issues.
4549 .\" .Ss "Signed and encrypted messages with S/MIME" {{{
4550 .Ss "Signed and encrypted messages with S/MIME"
4551 \*(OP S/MIME provides two central mechanisms:
4552 message signing and message encryption.
4553 A signed message contains some data in addition to the regular text.
4554 The data can be used to verify that the message was sent using a valid
4555 certificate, that the sender's address in the message header matches
4556 that in the certificate, and that the message text has not been altered.
4557 Signing a message does not change its regular text;
4558 it can be read regardless of whether the recipient's software is able to
4560 It is thus usually possible to sign all outgoing messages if so desired.
4561 Encryption, in contrast, makes the message text invisible for all people
4562 except those who have access to the secret decryption key.
4563 To encrypt a message, the specific recipient's public encryption key
4565 It is thus not possible to send encrypted mail to people unless their
4566 key has been retrieved from either previous communication or public key
4568 A message should always be signed before it is encrypted.
4569 Otherwise, it is still possible that the encrypted message text is
4572 A central concept to S/MIME is that of the certification authority (CA).
4573 A CA is a trusted institution that issues certificates.
4574 For each of these certificates it can be verified that it really
4575 originates from the CA, provided that the CA's own certificate is
4577 A set of CA certificates is usually delivered with OpenSSL and installed
4579 If you trust the source of your OpenSSL software installation,
4580 this offers reasonable security for S/MIME on the Internet.
4581 In general, a certificate cannot be more secure than the method its CA
4582 certificate has been retrieved with, though.
4583 Thus if you download a CA certificate from the Internet,
4584 you can only trust the messages you verify using that certificate as
4585 much as you trust the download process.
4587 The first thing you need for participating in S/MIME message exchange is
4588 your personal certificate, including a private key.
4589 The certificate contains public information, in particular your name and
4590 your email address, and the public key that is used by others to encrypt
4592 and to verify signed messages they supposedly received from you.
4593 The certificate is included in each signed message you send.
4594 The private key must be kept secret.
4595 It is used to decrypt messages that were previously encrypted with your
4596 public key, and to sign messages.
4598 For personal use it is recommended that you get a S/MIME certificate
4599 from one of the major CAs on the Internet using your WWW browser.
4600 (Many CAs offer such certificates for free.)
4601 You will usually receive a combined certificate and private key in
4602 PKCS#12 format which \*(UA does not directly accept.
4603 To convert it to PEM format, use the following shell command:
4605 .Dl $ openssl pkcs12 \-in cert.p12 \-out cert.pem \-clcerts \-nodes
4607 If you omit the `\-nodes' parameter, you can specifiy an additional `PEM
4608 pass phrase' for protecting the private key.
4609 \*(UA will then ask you for that pass phrase each time it signs or
4613 .Dl set smime-sign-cert-myname@myisp.example=cert.pem
4615 to make this private key and certificate known to \*(UA.
4616 You can now sign outgoing messages.
4622 From each signed message you send,
4623 the recipient can fetch your certificate and use it to send encrypted
4625 Accordingly if somebody sends you a signed message, you can do the same.
4628 command to check the validity of the certificate.
4629 After that, retrieve the certificate and tell \*(UA that it should use
4632 .Dl certsave filename
4633 .Dl set smime-encrypt-USER@HOST=filename
4635 You should carefully consider if you prefer to store encrypted messages
4637 If you do, anybody who has access to your mail folders can read them,
4638 but if you do not, you might be unable to read them yourself later if
4639 you happen to lose your private key.
4642 command saves messages in decrypted form, while the
4647 commands leave them encrypted.
4649 Note that neither S/MIME signing nor encryption applies to message
4650 subjects or other header fields.
4651 Thus they may not contain sensitive information for encrypted messages,
4652 and cannot be trusted even if the message content has been verified.
4653 When sending signed messages,
4654 it is recommended to repeat any important header information in the
4658 .\" .Ss "Using CRLs with S/MIME or SSL/TLS" {{{
4659 .Ss "Using CRLs with S/MIME or SSL/TLS"
4660 \*(OP Certification authorities (CAs) issue certificate revocation
4661 lists (CRLs) on a regular basis.
4662 These lists contain the serial numbers of certificates that have been
4663 declared invalid after they have been issued.
4664 Such usually happens because the private key for the certificate has
4666 because the owner of the certificate has left the organization that is
4667 mentioned in the certificate, etc.
4668 To seriously use S/MIME or SSL/TLS verification,
4669 an up-to-date CRL is required for each trusted CA.
4670 There is otherwise no method to distinguish between valid and
4671 invalidated certificates.
4672 \*(UA currently offers no mechanism to fetch CRLs, nor to access them on
4673 the Internet, so you have to retrieve them by some external mechanism.
4675 \*(UA accepts CRLs in PEM format only;
4676 CRLs in DER format must be converted, like, e.\|g.:
4678 .Dl $ openssl crl \-inform DER \-in crl.der \-out crl.pem
4680 To tell \*(UA about the CRLs, a directory that contains all CRL files
4681 (and no other files) must be created.
4686 variables, respectively, must then be set to point to that directory.
4687 After that, \*(UA requires a CRL to be present for each CA that is used
4688 to verify a certificate.
4691 .\" .Ss "Handling spam" {{{
4693 \*(OP \*(UA can make use of spam detection and learning facilities \(en
4694 more precisely, SpamAssassin (\%<http://spamassassin.apache.org>).
4695 A very comprehensive documentation of
4697 can be found at the O'Reilly Commons
4698 (\%<http://commons.oreilly.com/wiki/index.php/SpamAssassin>).
4700 Currently \*(UA supports interaction with
4702 only via its daemonized
4705 server / client pair, which means that, in order to detect and work
4706 with spam through \*(UA, an instance of the
4708 daemon must be running (the examples are equivalent):
4709 .Bd -literal -offset indent
4710 $ spamd -i localhost:2142 -i /tmp/.spamsock -d [-L] [-l]
4711 $ spamd --listen=localhost:2142 --listen=/tmp/.spamsock \\
4712 --daemonize [--local] [--allow-tell]
4717 should only listen on a local, path-based UNIX domain socket instead of
4718 offering its service over the network, it maybe necessary to use
4721 option instead of the shown
4723 In order to support training of the Bayesian classifier through \*(UA,
4725 must have been started with the
4731 is running \*(UA can classify messages by using the client side program,
4734 .Bd -literal -offset indent
4735 $ \*(ua -Sspam-command=/usr/local/bin/spamc \\
4736 -Sspam-socket=/tmp/.spamsock -Sspam-maxsize=500000
4739 The commands offered are
4743 which simply set an `is-spam' flag that can be used for, e.g., message
4746 which passes messages through to the spam detector in order to gain
4747 a spam score and conditionally set the `is-spam' flag accordingly,
4748 as well as the Bayesian filter related
4754 Because messages must exist on local storage in order to be scored (or
4755 used for Bayesian filter training), it is possibly a good idea to
4756 perform the local spam check last:
4757 .Bd -literal -offset indent
4758 define spamdelhook {
4760 spamset (header x-dcc-brand-metrics "bulk")
4761 # Server-side spamassassin(1)
4762 spamset (header x-spam-flag "YES")
4763 del :s # TODO we HAVE to be able to do `spamrate :u ! :s'
4764 # And finally the local spamc(1)
4768 set folder-hook-FOLDER=spamdelhook
4771 See also the documentation for the variables
4781 .\" .Ss "Sending mail from scripts" {{{
4782 .Ss "Sending mail from scripts"
4783 If you want to send mail from scripts, you must be aware that \*(UA
4784 reads the user's configuration files by default.
4785 So unless your script is only intended for your own personal use
4786 (as, e.g., a cron job), you need to circumvent this:
4788 .Dl MAILRC=/dev/null \*(ua \-n
4790 You then need to create a script-local configuration for \*(UA.
4791 This can be done by either pointing the
4793 variable to a custom configuration file,
4794 by passing the configuration in environment variables,
4797 command line option to specify options.
4798 Since many configuration options are not valid shell variables, the
4800 command is useful if the approach via environment variables is used:
4801 .Bd -literal -offset indent
4802 env MAILRC=/dev/null password=secret \*(ua -n -Sv15-compat \e
4803 -S 'smtp=smtps://mylogin@some.host:465' -Ssmtp-auth=login \e
4804 -S 'from=scriptreply@domain' \e
4805 -s 'subject' -a attachment_file recipient@domain < content_file
4810 .\" .Sh "SEE ALSO" {{{
4823 .Xr spamassassin 1 ,
4841 .\" .Sh "IMPLEMENTATION NOTES" {{{
4842 .Sh "IMPLEMENTATION NOTES"
4843 The character set conversion uses and relies upon the
4846 Its functionality differs widely between the various system environments
4849 Limitations with IMAP mailboxes are:
4850 It is not possible to edit messages, but it is possible to append them.
4851 Thus to edit a message, create a local copy of it, edit it, append it,
4852 and delete the original.
4853 The line count for the header display is only appropriate if the entire
4854 message has been downloaded from the server.
4855 The marking of messages as `new' is performed by the IMAP server;
4860 will not cause it to be reset, and if the
4862 variable is unset, messages that arrived during a session will not be
4863 in state `new' anymore when the folder is opened again.
4864 Also if commands queued in disconnected mode are committed,
4865 the IMAP server will delete the `new' flag for all messages in the
4867 and new messages will appear as unread when it is selected for viewing
4869 The `flagged', `answered', and `draft' attributes are usually permanent,
4870 but some IMAP servers are known to drop them without notification.
4871 Message numbers may change with IMAP every time before the prompt is
4872 printed if \*(UA is notified by the server that messages have been
4873 deleted by some other client or process.
4874 In this case, `Expunged n messages' is printed, and message numbers may
4877 Limitations with POP3 mailboxes are:
4878 It is not possible to edit messages, they can only be copied and deleted.
4879 The line count for the header display is only appropriate if the entire
4880 message has been downloaded from the server.
4881 The status field of a message is maintained by the server between
4882 connections; some servers do not update it at all, and with a server
4883 that does, the `exit' command will not cause the message status to be
4885 The `newmail' command and the `newmail' variable have no effect.
4886 It is not possible to rename or to remove POP3 mailboxes.
4888 If a `RUBOUT' (interrupt, `control-C') is typed while an IMAP or POP3
4889 operation is in progress, \*(UA will wait until the operation can be
4891 and will then return to the command loop and print the prompt again.
4892 When a second `RUBOUT' is typed while \*(UA is waiting for the operation
4893 to complete, the operation itself will be cancelled.
4894 In this case, data that has not been fetched yet will have to be fetched
4895 before the next command can be performed.
4896 If the cancelled operation was using an SSL/TLS encrypted channel,
4897 an error in the SSL transport will very likely result and render the
4898 connection unusable.
4900 As \*(UA is a mail user agent, it provides only basic SMTP services.
4901 If it fails to contact its upstream SMTP server, it will not make
4902 further attempts to transfer the message at a later time,
4903 and it does not leave other information about this condition than an
4904 error message on the terminal and an entry in
4906 This is usually not a problem if the SMTP server is located in the same
4907 local network as the computer on which \*(UA is run.
4908 However, care should be taken when using a remote server of an ISP;
4909 it might be better to set up a local SMTP server then which just acts as
4912 \*(UA immediately contacts the SMTP server (or
4914 ) even when operating in
4917 It would not make much sense for \*(UA to defer outgoing mail since SMTP
4918 servers usually provide much more elaborated delay handling than \*(UA
4919 could perform as a client.
4920 Thus the recommended setup for sending mail in
4922 mode is to configure a local SMTP server such that it sends outgoing
4923 mail as soon as an external network connection is available again,
4924 i.e., to advise it to do that from a network startup script.
4929 A \fImail\fR command appeared in Version 1 AT&T Unix.
4930 Berkeley Mail was written in 1978 by Kurt Shoens.
4931 This man page is derived from from The Mail Reference Manual originally
4932 written by Kurt Shoens.
4933 "Heirloom Mailx" enhancements are maintained and documented by Gunnar
4935 "S-nail" is maintained and documented by Steffen (Daode) Nurpmeso.
4937 Portions of this text are reprinted and reproduced in electronic form
4938 from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
4939 \(en Operating System Interface (POSIX), The Open Group Base
4940 Specifications Issue 6, Copyright \(co 2001-2003 by the Institute of
4941 Electrical and Electronics Engineers, Inc and The Open Group.
4942 In the event of any discrepancy between this version and the original
4943 IEEE and The Open Group Standard, the original IEEE and The Open Group
4944 Standard is the referee document.
4945 The original Standard can be obtained online at
4946 \%<http://www.opengroup.org/unix/online.html>.
4947 Redistribution of this material is permitted so long as this notice
4953 .An "Christos Zoulas" ,
4954 .An "Gunnar Ritter" ,
4955 .An Steffen Po Daode Pc Nurpmeso Aq s-nail-users@lists.sourceforge.net
4958 Too many (see the file `TODO' from the distribution or the repository).