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
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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 support is available
479 will be interpreted as one if any of the `magic'al regular expression
482 .Ar @ Ns Ar name-list
483 part is missing, the search is restricted to the subject field body,
486 specifies a comma-separated list of header fields to search, as in
488 .Dl '@to,from,cc@Someone i ought to know'
490 The special names `body' and `text' can be used to search in message
491 bodies \(en whereas the former searches only the body, the latter form
492 also performs a fulltext search in the header fields.
493 In order to search for a string that includes a `@' (commercial at)
496 is effectively non-optional, but may be given as the empty string.
500 By default, this is a case-sensitive search for the complete email
505 only the local part of the addresses is evaluated for the comparison.
509 a case-sensitive search for the complete real name of a sender is
512 .Ns ` Ns Li "(from address)" Ns '
513 expression can be used instead if substring matches are desired.
517 \*(OP IMAP-style SEARCH expressions may also be used.
518 This addressing mode is available with all types of folders;
519 for folders not located on IMAP servers,
520 or for servers unable to execute the SEARCH command,
521 \*(UA will perform the search locally.
522 Strings must be enclosed by double quotes `"' in their entirety
523 if they contain white space or parentheses;
525 only backslash `\e' is recognized as an escape character.
526 All string searches are case-insensitive.
527 When the description indicates that the `envelope' representation of an
528 address field is used,
529 this means that the search string is checked against both a list
532 .Dl ( \*q Ns name Ns \*q \*q Ns source Ns \*q \*q Ns \
533 local-part Ns \*q \*q Ns domain-part Ns \*q )
536 and the addresses without real names from the respective header field.
537 These search expressions can be nested using parentheses, see below for
539 .Bl -tag -width ".It .Ar :n:u"
541 All messages that satisfy the given
543 .It Ar ( criterion1 criterion2 ... criterionN )
544 All messages that satisfy all of the given criteria.
545 .It Ar ( or criterion1 criterion2 )
546 All messages that satisfy either
551 To connect more than two criteria using `or',
552 (or) specifications have to be nested using additional parentheses,
554 .Ns ` Ns Li "(or a (or b c))" Ns ',
556 .Ns ` Ns Li "(or a b c)" Ns '
558 .Ns ` Ns Li "((a or b) and c)" Ns '.
559 For a simple `or' operation of independent criteria on the lowest
561 it is possible to achieve similar effects by using three separate
563 .Ns ` Ns Li "(a) (b) (c)" Ns '.
564 .It Ar ( not criterion )
565 All messages that do not satisfy
567 .It Ar ( bcc \*q Ns Ar string Ns Ar \*q )
568 All messages that contain
570 in the `envelope' representation of the `Bcc:' field.
571 .It Ar ( cc \*q Ns Ar string Ns Ar \*q )
572 All messages that contain
574 in the `envelope' representation of the `Cc:' field.
575 .It Ar ( from \*q Ns Ar string Ns Ar \*q )
576 All messages that contain
578 in the `envelope' representation of the `From:' field.
579 .It Ar ( subject \*q Ns Ar string Ns Ar \*q )
580 All messages that contain
582 in the `Subject:' field.
583 .It Ar ( to \*q Ns Ar string Ns Ar \*q )
584 All messages that contain
586 in the `envelope' representation of the `To:' field.
587 .It Ar ( header name \*q Ns Ar string Ns Ar \*q )
588 All messages that contain
593 .It Ar ( body \*q Ns Ar string Ns Ar \*q )
594 All messages that contain
597 .It Ar ( text \*q Ns Ar string Ns Ar \*q )
598 All messages that contain
600 in their header or body.
601 .It Ar ( larger size )
602 All messages that are larger than
605 .It Ar ( smaller size )
606 All messages that are smaller than
609 .It Ar ( before date )
610 All messages that were received before
612 which must be in the form
613 .Li "d[d]-mon-yyyy" ,
614 where `d' denotes the day of the month as one or two digits,
615 `mon' is the name of the month \(en one of
616 `Jan', `Feb', `Mar', `Apr', `May', `Jun',
617 `Jul', `Aug', `Sep', `Oct', `Nov', or `Dec',
618 and `yyyy' is the year as four digits, e.g., "28-Dec-2012".
620 All messages that were received on the specified date.
621 .It Ar ( since date )
622 All messages that were received since the specified date.
623 .It Ar ( sentbefore date )
624 All messages that were sent on the specified date.
625 .It Ar ( senton date )
626 All messages that were sent on the specified date.
627 .It Ar ( sentsince date )
628 All messages that were sent since the specified date.
630 The same criterion as for the previous search.
631 This specification cannot be used as part of another criterion.
632 If the previous command line contained more than one independent
633 criterion then the last of those criteria is used.
637 .\" .Ss "Replying to or originating mail" {{{
638 .Ss "Replying to or originating mail"
641 can be used to set up a response to a message,
642 sending it back to the person who it was from.
643 Text the user types in, up to an end-of-file,
644 defines the contents of the message.
645 While the user is composing a message \*(UA treats lines beginning with
646 the character `~' specially.
647 For instance, typing `~m' (alone on a line) will place a copy of the
648 current message into the response right shifting it by a tabstop
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
1287 Marks the end of the then-part of an if statement and the beginning of
1288 the part to take effect if the condition of the if statement is false.
1290 Marks the end of an if statement.
1292 (ex or x) Effects an immediate return to the Shell without modifying the
1293 user's system mailbox, his `mbox' file, or his edit file in
1295 as well as a possibly tracked command line editor history file.
1297 Print the list of features that have been compiled into \*(UA.
1302 (fl) Takes a message list and marks the messages as `flagged' for
1303 urgent/special attention.
1304 This mark has no technical meaning in the mail system;
1305 it just causes messages to be highlighted in the header summary,
1306 and makes them specially addressable.
1308 (fold) The folder command switches to a new mail file or folder.
1309 With no arguments, it tells the user which file he is currently reading.
1310 If an argument is given, it will write out changes (such as deletions)
1311 the user has made in the current file and read in the new file.
1312 Some special conventions are recognized for the
1315 .Bl -tag -offset indent -width ".Ar %:filespec"
1317 (number sign) means the previous file,
1319 (percent sign) means the invoking user's system mailbox
1324 means the system mailbox of `user'
1325 (and never the value of
1327 regardless of its actual setting),
1329 (ampersand) means the invoking user's `mbox' file (see
1333 means a `file' in the
1337 expands to the same value as `filespec',
1338 but the file is handled as a system mailbox by, e.g., the
1345 If the name matches one of the strings defined with the command
1347 it is replaced by its long form and expanded.
1348 If the name ends with `.gz', `.bz2' or `.xz' it is treated as being
1355 If `name' refers to a directory with the subdirectories `tmp', `new',
1356 and `cur', then it is treated as a folder in `maildir' format.
1359 .Dl \*(IN protocol://[user[:password]@]host[:port][/path]
1360 .Dl \*(OU protocol://[user@]host[:port][/path]
1362 is taken as an Internet mailbox specification.
1363 The \*(OPally supported protocols are `imap' (IMAP v4r1), `imaps'
1364 (IMAP with SSL/TLS encrypted transport), `pop3' (POP3) and `pop3s' (POP3
1365 with SSL/TLS encrypted transport).
1366 The `[/path]' part is valid only for IMAP; there it defaults to `INBOX'.
1368 \*(IN If `user' or `password' contain special characters, in particular
1369 whitespace, `/', `:' or `%', they must be specified in URL notation
1372 may be helpful for preparation).
1373 If no `user' is specified in the URL, the
1375 variable chain is inspected; likewise the
1377 variable chain for the password.
1379 \*(OU If `user' contains special characters, in particular `/' or `%',
1380 they must be escaped in URL notation \(en the command
1382 can be used to show the necessary conversion.
1383 The optional `path' part applies to IMAP only;
1384 if it is omitted, the default `INBOX' is used.
1386 If \*(UA is connected to an IMAP server,
1387 a name of the form `@mailbox' refers to the `mailbox' on that server,
1388 but otherwise a `@' prefix has no special meaning.
1390 With no arguments, list the names of the folders in the folder directory.
1391 With an existing folder as an argument,
1392 lists the names of folders below the named folder;
1393 e.\|g. the command `folders @' lists the folders on the base level of
1394 the current IMAP server.
1395 See also the variable
1396 .Va imap-list-depth .
1400 but saves the message in a file named after the local part of the first
1401 recipient's address.
1405 but saves the message in a file named after the local part of the first
1406 recipient's address.
1410 but responds to all recipients regardless of the
1415 .It Ic followupsender
1418 but responds to the sender only regardless of the
1424 (fwd) Takes a message and the address of a recipient
1425 and forwards the message to him.
1426 The text of the original message is included in the new one,
1427 with the value of the
1429 variable printed before.
1434 commands specify which header fields are included in the new message.
1435 Only the first part of a multipart message is included unless the
1436 .Va forward-as-attachment
1441 but saves the message in a file named after the local part of the
1442 recipient's address.
1444 (f) Takes a list of messages and prints their message headers,
1445 piped through the pager if the output does not fit on the screen.
1447 Specifies which header fields are to be ignored with the command
1449 This command has no effect when the
1450 .Va forward-as-attachment
1453 Specifies which header fields are to be retained with the command
1458 This command has no effect when the
1459 .Va forward-as-attachment
1462 Without arguments it lists all currently defined command aliases,
1464 With two arguments it defines a new command alias: the first argument is
1465 the name under which the second should be accessible.
1466 The content of the second argument can be just about anything.
1467 A ghost can be used everywhere a normal command can be used, but always
1468 takes precedence; any arguments that are given to the command alias are
1469 joined onto the alias content, and the resulting string forms the
1470 command line that is, in effect, executed.
1474 .Dl ? ghost ls '!ls -latro'
1477 (h) Lists the current range of headers, which is an 18-message group.
1478 If a `+' argument is given the next 18-message group is printed,
1479 likewise the previous is printed if the argument was `-'.
1487 the list of history entries;
1490 argument selects and shows the respective history entry \(en
1491 press `ENTER' to accept it, and the history entry will become the new
1493 The default mode if no arguments are given is
1496 (ho, also preserve) Takes a message list and marks each message therein
1497 to be saved in the user's system mailbox instead of in `mbox'.
1498 Does not override the
1501 \*(UA deviates from the POSIX standard with this command,
1504 command issued after
1506 will display the following message, not the current one.
1508 Commands in \*(UA's startup files can be executed conditionally by
1509 testing conditions via the nestable command `if', as in:
1510 .Bd -literal -offset indent
1518 Note that the only allowed conditions are `[Rr]eceive', `[Ss]end',
1519 `[Tt]erm' (execute if standard input is a tty), as well as `0' (never
1520 execute) and `1' (always execute).
1521 In addition it is possible to conditionalize upon wether an option is set,
1522 or set to a specific value, by using the `$' conditional trigger, e.g.:
1523 .Bd -literal -offset indent
1527 if $encoding == "UTF-8"
1530 if $encoding != "UTF-8"
1535 The first form simply checks wether an option is set, the other two also
1536 perform value content comparison (equality and non-equality,
1537 respectively); an unset value is treated as the empty string, then.
1539 Add the list of header fields named to the ignored list.
1540 Header fields in the ignore list are not printed on the terminal when
1541 a message is printed.
1542 This command is very handy for suppression of certain machine-generated
1548 commands can be used to print a message in its entirety, including
1550 It lists the current set of ignored fields if no arguments were given.
1552 \*(OP Sends command strings directly to the current IMAP server.
1553 \*(UA operates always in IMAP `selected state' on the current mailbox;
1554 commands that change this will produce undesirable results and should be
1556 Useful IMAP commands are:
1557 .Bl -tag -offset indent -width ".Ic getquotearoot"
1559 Takes the name of an IMAP mailbox as an argument and creates it.
1561 (RFC 2087) Takes the name of an IMAP mailbox as an argument
1562 and prints the quotas that apply to the mailbox.
1563 Not all IMAP servers support this command.
1565 (RFC 2342) Takes no arguments and prints the Personal Namespaces,
1566 the Other User's Namespaces and the Shared Namespaces.
1567 Each namespace type is printed in parentheses;
1568 if there are multiple namespaces of the same type,
1569 inner parentheses separate them.
1570 For each namespace a prefix and a hierarchy separator is listed.
1571 Not all IMAP servers support this command.
1577 Prints the names of all available commands, alphabetically sorted.
1579 Can only be used inside of a macro definition block introduced by
1583 and is interpreted as a boolean (value `0' means false, everything
1585 Any option that had been set while `localopts' was in effect will be
1586 reverted to its former value once the block is left / the `account'
1588 .Bd -literal -offset indent
1589 define temporary_settings {
1599 Note that these options stack upon each other, i.e., if macro1 sets
1600 `localopts' and calls macro2, which explicitly resets `localopts', then
1601 any values set within macro2 will still be cleaned up by macro1.
1605 but saves the message in a file named after the local part of the first
1606 recipient's address.
1608 (m) Takes a (list of) recipient address(es) as (an) argument(s),
1609 or asks on standard input if none were given;
1610 then collects the remaining mail content and sends it out.
1612 The given message list is to be sent to `mbox' when \*(UA is quit.
1613 This is the default action unless the
1616 \*(UA deviates from the POSIX standard with this command,
1619 command issued after
1621 will display the following message, not the current one.
1630 In the former case all sources are loaded first as necessary.
1632 .Va mimetypes-load-control
1633 option can be used to fine-tune which sources are loaded.
1637 but marks the messages for deletion if they were transferred
1640 Takes a message list and invokes the
1642 on that list, printing a form-feed (`\\f') in between messages.
1646 but also prints ignored header fields and all MIME parts.
1650 but moves the messages to a file named after the local part of the
1651 sender address of the first message.
1653 Checks for new mail in the current folder without committing any changes
1655 If new mail is present, a message is printed.
1659 the headers of each new message are also printed.
1661 (n) (like `+' or `ENTER') Goes to the next message in sequence
1663 With an argument list, types the next matching message.
1674 If the current folder is located on an IMAP or POP3 server,
1675 a `NOOP' command is sent.
1676 Otherwise, no operation is performed.
1680 but also pipes ignored header fields and all parts of MIME
1681 `multipart/alternative' messages.
1683 (pi) Takes a message list and a shell command
1684 and pipes the messages through the command.
1685 Without an argument the current message is piped through the command
1692 every message is followed by a formfeed character.
1699 but also prints out ignored header fields and all parts of MIME
1700 `multipart/alternative' messages.
1707 (p) Takes a message list and types out each message on the user's
1709 If the message is a MIME multipart message,
1710 all parts with a content type of `text' or `message' are shown,
1711 the other are hidden except for their headers.
1712 Messages are decrypted and converted to the terminal character set
1715 (q) Terminates the session, saving all undeleted, unsaved messages in
1716 the current `mbox', preserving all messages marked with
1720 or never referenced in his system mailbox,
1721 and removing all other messages from his system mailbox.
1722 If new mail has arrived during the session,
1723 the message `You have new mail' is given.
1724 If given while editing a mailbox file with the command line flag
1726 then the edit file is rewritten.
1727 A return to the shell is effected,
1728 unless the rewrite of edit file fails,
1729 in which case the user can escape with the exit command.
1737 (rem) Removes the named folders.
1738 The user is asked for confirmation in interactive mode.
1740 (ren) Takes the name of an existing folder
1741 and the name for the new folder
1742 and renames the first to the second one.
1743 Both folders must be of the same type
1744 and must be located on the current server for IMAP.
1746 (R) Reply to originator.
1747 Does not reply to other recipients of the original message.
1749 (r) Takes a message list and sends mail to the sender and all recipients
1750 of the specified messages.
1751 The default message must not be deleted.
1755 but responds to all recipients regardless of the
1763 but responds to the sender only regardless of the
1771 but does not add any header lines.
1772 This is not a way to hide the sender's identity,
1773 but useful for sending a message again to the same recipients.
1775 Takes a list of messages and a user name
1776 and sends each message to the named user.
1777 `Resent-From:' and related header fields are prepended to the new copy
1788 .It Ic respondsender
1792 Add the list of header fields named to the retained list.
1793 Only the header fields in the retain list are shown on the terminal when
1794 a message is printed, all other header fields are suppressed.
1799 commands can be used to print a message in its entirety.
1800 The current set of retained fields is shown if
1802 is used without arguments.
1806 but saves the messages in a file named after the local part of the
1807 sender of the first message instead of taking a filename argument.
1809 (s) Takes a message list and a filename and appends each message in turn
1810 to the end of the file.
1811 If no filename is given, the `mbox' file is used.
1812 The filename in quotes, followed by the line count and character count
1813 is echoed on the user's terminal.
1814 If editing a system mailbox the messages are marked for deletion.
1815 Compressed files and IMAP mailboxes are handled as described for the
1817 command line option above.
1830 Header fields thus marked are filtered out when saving a message by
1832 or when automatically saving to `mbox'.
1833 This command should only be applied to header fields that do not contain
1834 information needed to decode the message,
1835 as MIME content fields do.
1836 If saving messages on an IMAP account ignoring fields makes it
1837 impossible to copy the data directly on the server,
1838 thus operation usually becomes much slower.
1848 Header fields thus marked are the only ones saved with a message when
1851 or when automatically saving to `mbox'.
1855 The use of this command is strongly discouraged since it may strip
1856 header fields that are needed to decode the message correctly.
1858 Takes a message list and marks all messages as having been read.
1860 (se) With no arguments, prints all variable values.
1861 Otherwise, sets an option.
1862 Arguments are of the form `option=value' (no space before or after `='),
1863 or plain `option' if there is no value.
1864 Quotation marks may be placed around any part of the assignment
1865 statement to quote blanks or tabs, e.g.,
1867 .Dl set indentprefix="->"
1869 If an argument begins with `no', as in `set nosave',
1870 the effect is the same as invoking the
1872 command with the remaining part of the variable (`unset save').
1876 except that the options are also exported into the program environment;
1877 since this task requires native host support the command will always
1878 report error if that is not available (but still act like
1881 This operation is a no-op unless all resource files have been loaded.
1885 (sh) Invokes an interactive version of the shell.
1887 Defines a shortcut name and its string for expansion,
1888 as described for the
1891 If used without arguments the currently defined shortcuts are printed.
1895 but performs neither MIME decoding nor decryption so that the raw
1896 message text is shown.
1898 Print the size in characters of each message of the given message-list.
1900 Create a sorted representation of the current folder,
1903 command and the addressing modes such that they refer to messages in the
1905 Message numbers are the same as in regular mode.
1909 a header summary in the new order is also printed.
1910 Possible sorting criteria are:
1911 .Bl -tag -offset indent -width "subject"
1913 Sort the messages by their `Date:' field,
1914 that is by the time they were sent.
1916 Sort messages by the value of their `From:' field,
1917 that is by the address of the sender.
1921 the sender's real name (if any) is used.
1923 Sort the messages by their size.
1925 \*(OP Sort the message by their spam score, as has been classified via
1929 Sort the messages by their message status (new, read, old, etc.).
1931 Sort the messages by their subject.
1933 Create a threaded order,
1937 Sort messages by the value of their `To:' field,
1938 that is by the address of the recipient.
1942 the recipient's real name (if any) is used.
1945 If no argument is given,
1946 the current sorting criterion is printed.
1948 The source command reads commands from a file.
1950 \*(OP Takes a list of messages and clears their `is-spam' flag.
1952 \*(OP Takes a list of messages and forces the spam detector to forget it
1953 has ever used them to train its Bayesian filter, wether as `ham' or
1956 \*(OP Takes a list of messages and teaches them to the spam detector as
1958 This also clears the `is-spam' flag of the messages in question.
1960 \*(OP Takes a list of messages and rates them using the configured spam
1961 detector, setting their `is-spam' flag as appropriate.
1962 Note that the messages are not modified, and due to that the rating will
1963 get lost once the mailbox is left.
1964 Refer to the manual section
1966 for the complete picture of spam handling in \*(UA.
1968 \*(OP Takes a list of messages and sets their `is-spam' flag.
1970 \*(OP Takes a list of messages and teaches them to the spam detector as
1972 This also sets the `is-spam' flag of the messages in question.
1974 (th) Create a threaded representation of the current folder,
1975 i.\|e. indent messages that are replies to other messages in the header
1976 display and change the
1978 command and the addressing modes such that they refer to messages in the
1980 Message numbers are the same as in unthreaded mode.
1984 a header summary in threaded order is also printed.
1986 Takes a message list and prints the top few lines of each.
1987 The number of lines printed is controlled by the variable
1989 and defaults to five.
1991 Takes a message list and marks the messages for saving in `mbox'.
1992 \*(UA deviates from the POSIX standard with this command,
1995 command issued after `mbox' will display the following message instead
1998 (T) Identical to the
2005 Delete all given accounts.
2006 An error message is printed if a given account is not defined.
2007 Attempts to delete the currently active account are rejected.
2009 Takes a list of names defined by alias commands
2010 and discards the remembered groups of users.
2012 Takes a message list and marks each message as not having been answered.
2014 (unc) Only applicable to threaded mode.
2015 Takes a message list and makes the message and all replies to it visible
2016 in header summaries again.
2017 When a message becomes the current message,
2018 it is automatically made visible.
2019 Also when a message with collapsed replies is printed,
2020 all of these are automatically uncollapsed.
2022 Undefine all given macros.
2023 An error message is printed if a given macro is not defined.
2025 (u) Takes a message list and marks each message as not being deleted.
2027 Takes a message list and
2028 .Ns un Ns Ic draft Ns
2031 Takes a message list and marks each message as not being
2034 Removes the header field names from the list of ignored fields for the
2038 Removes the header field names from the list of retained fields for the
2042 Remove an existing command
2045 Removes the header field names from the list of ignored fields.
2050 (U) Takes a message list and marks each message as not having been read.
2052 Removes the header field names from the list of retained fields.
2054 Removes the header field names from the list of ignored fields for
2057 Removes the header field names from the list of retained fields for
2060 Takes a list of option names and discards their remembered values;
2066 except that the options are also removed from the program environment;
2067 since this task requires native host support the command will always
2068 report error if that is not available (but still act like
2071 This operation is a no-op unless all resource files have been loaded.
2075 Deletes the shortcut names given as arguments.
2077 Disable sorted or threaded mode
2083 return to normal message order and,
2087 print a header summary.
2092 Decode the given URL-encoded string arguments and show the results.
2094 URL-encode the given arguments and show the results.
2096 Show information about all given options.
2098 \*(OP (verif) Takes a message list and verifies each message.
2099 If a message is not an S/MIME signed message,
2100 verification will fail for it.
2101 The verification process checks if the message was signed using a valid
2103 if the message sender's email address matches one of those contained
2104 within the certificate,
2105 and if the message content has been altered.
2107 (v) Takes a message list and invokes the display editor on each message.
2108 Modified contents are discarded unless the
2112 (w) For conventional messages the body without all headers is written.
2113 The output is decrypted and converted to its native format as necessary.
2114 If the output file exists, the text is appended.
2115 If a message is in MIME multipart format its first part is written to
2116 the specified file as for conventional messages,
2117 and the user is asked for a filename to save each other part.
2118 For convience saving of each part may be skipped by giving an empty value;
2119 the same result can also be achieved by writing it to
2121 For the second and subsequent parts a leading `|' character causes the
2122 part to be piped to the remainder of the user input interpreted as
2124 otherwise the user input is expanded as usually for folders,
2125 e.g., tilde expansion is performed.
2126 In non-interactive mode, only the parts of the multipart message
2127 that have a filename given in the part header are written,
2128 the others are discarded.
2129 The original message is never marked for deletion in the originating
2132 the contents of the destination file are overwritten if the file
2134 No special handling of compressed files is performed.
2139 \*(UA presents message headers in windowfuls as described under the
2142 This command scrolls to the next window of messages.
2143 If an argument is given,
2144 it specifies the window to use.
2145 A number prefixed by `+' or `\-' indicates
2146 that the window is calculated in relation to the current position.
2147 A number without a prefix specifies an absolute window number,
2148 and a `$' lets \*(UA scroll to the last window of messages.
2152 but scrolls to the next or previous window that contains at least one
2153 new or `flagged' message.
2157 .\" .Ss "Tilde escapes" {{{
2159 Here is a summary of the tilde escapes,
2160 which are used to perform special functions when composing messages.
2161 Tilde escapes are only recognized at the beginning of lines.
2162 The name `tilde escape' is somewhat of a misnomer since the actual
2163 escape character can be set by the option
2165 .Bl -tag -width ".Ic ~< filename"
2167 Insert the string of text in the message prefaced by a single `~'.
2168 (If the escape character has been changed,
2169 that character must be doubled
2170 in order to send it at the beginning of a line.)
2171 .It Ic ~! Ar command
2172 Execute the indicated shell
2174 then return to the message.
2176 Same effect as typing the end-of-file character.
2177 .It Ic ~: Ar \*(UA-command Ns \ or Ic ~_ Ar \*(UA-command
2178 Execute the given \*(UA command.
2179 Not all commands, however, are allowed.
2181 Write a summary of command escapes.
2182 .It Ic ~< Ar filename
2185 .It Ic ~<! Ar command
2187 is executed using the shell.
2188 Its standard output is inserted into the message.
2189 .It Ic ~@ Op Ar filename...
2190 With no arguments, edit the attachment list interactively.
2191 If an attachment's file name is left empty,
2192 that attachment is deleted from the list.
2193 When the end of the attachment list is reached,
2194 \*(UA will ask for further attachments until an empty name is given.
2195 If a given file name solely consists of the number sign `#' followed
2196 by a valid message number of the currently active mailbox, the given
2197 message is attached as a MIME `message/rfc822' and the rest of this
2198 section does not apply.
2200 If character set conversion has been compiled into \*(UA, then this mode
2201 gives the user the option to specify input and output character sets,
2202 unless the file extension indicates binary content, in which case \*(UA
2203 asks wether this step shall be skipped for the attachment in question.
2204 If not skipped, then the charset that succeeds to represent the
2205 attachment data will be used in the `charset=' MIME parameter of the
2209 If input and output character sets are specified, then the conversion is
2210 performed on the fly.
2211 The user will be asked repeatedly until the desired conversion succeeds.
2213 If only an output character set is specified, then the input is assumed
2216 charset and will be converted to the given output charset on the fly.
2217 The user will be asked repeatedly until the desired conversion succeeds.
2219 If no character sets are specified at all then the algorithm that is
2220 documented in the section
2221 .Sx "Character sets"
2222 is applied, but directly and on the fly.
2223 The user will be asked repeatedly until the desired conversion succeeds.
2225 Finally, if an input-, but no output character set is specified, then no
2226 conversion is ever performed, but the `charset=' MIME parameter will
2227 still be set to the user input.
2229 The character set selection loop can be left by typing `control-C',
2230 i.e., causing an interrupt.
2231 .\" \*(OU next sentence
2232 Note that before \*(UA version 15.0 this terminates the entire
2233 current attachment selection, not only the character set selection.
2236 Without character set conversion support, \*(UA will ask for the input
2237 character set only, and it'll set the `charset=' MIME parameter to the
2238 given input, if any;
2239 if no user input is seen then the
2241 character set will be used for the `charset=' parameter instead.
2242 Note that the file extension check isn't performed in this mode, since
2243 no conversion will take place anyway.
2245 Note that in non-interactive mode, for reproduceabilities sake, there
2246 will always be two questions for each attachment, regardless of wether
2247 character set conversion is available and what the file extension is.
2248 The first asks for the filename, and the second asks for the input
2249 character set to be passed through to the `charset=' MIME parameter;
2250 no conversion will be tried if there is input to the latter question,
2251 otherwise the usual conversion algorithm, as above, is applied.
2252 For message attachments, the answer to the second question is completely
2257 arguments are specified,
2258 they are treated as a comma separated list of files,
2259 which are all expanded and appended to the end of the attachment list.
2260 (Filenames with commas, or with leading or trailing whitespace can only
2261 be added via the command line or the first method.
2262 Message attachments can only be added via the first method;
2263 filenames which clash with message numbers can only be added via the
2264 command line or the second method.)
2265 In this mode the (text) attachments are assumed to be in
2267 encoding, and will be evaluated as documented in the section
2268 .Sx "Character sets" .
2270 Inserts the string contained in the
2272 variable (same as `~i Sign').
2273 The escape sequences `\et' (tabulator) and `\en' (newline) are understood.
2275 Inserts the string contained in the
2277 variable (same as `~i sign').
2278 The escape sequences `\et' (tabulator) and `\en' (newline) are understood.
2279 .It Ic ~b Ar name ...
2280 Add the given names to the list of blind carbon copy recipients.
2281 .It Ic ~c Ar name ...
2282 Add the given names to the list of carbon copy recipients.
2284 Read the file specified by the
2286 variable into the message.
2288 Invoke the text editor on the message collected so far.
2289 After the editing session is finished,
2290 the user may continue appending text to the message.
2291 .It Ic ~f Ar messages
2292 Read the named messages into the message being sent.
2293 If no messages are specified,
2294 read in the current message.
2295 Message headers currently being ignored (by the
2299 command) are not included.
2300 For MIME multipart messages,
2301 only the first printable part is included.
2302 .It Ic ~F Ar messages
2303 Identical to `~f', except that all message headers and MIME parts are
2306 Edit the message header fields `To:', `Cc:', `Bcc:', and `Subject:' by
2307 typing each one in turn and allowing the user to edit the field.
2309 Edit the message header fields `From:', `Reply-To:', `Sender:' and
2310 `Organization:' in the same manner as described for
2312 The default values for these fields originate from the
2319 .It Ic ~i Ar variable
2320 Insert the value of the specified variable into the message,
2321 adding a newline character at the end.
2322 The message remains unaltered if the variable is unset or empty.
2323 The escape sequences `\et' (tabulator) and `\en' (newline) are understood.
2324 .It Ic ~m Ar messages
2325 Read the named messages into the message being sent,
2326 indented by a tab or by the value of
2328 If no messages are specified,
2329 read the current message.
2330 Message headers currently being ignored (by the
2334 commands) are not included.
2335 For MIME multipart messages,
2336 only the first printable part is included.
2337 .It Ic ~M Ar messages
2338 Identical to `~m', except that all message headers and MIME parts are
2341 Print out the message collected so far,
2342 prefaced by the message header fields
2343 and followed by the attachment list, if any.
2345 Abort the message being sent,
2346 copying it to the file specified by the
2351 .It Ic ~r Ar filename
2352 Read the named file into the message.
2354 Cause the named string to become the current subject field.
2355 .It Ic ~t Ar name ...
2356 Add the given name(s) to the direct recipient list.
2357 .It Ic ~u Ar messages
2358 Like `~f', but exclude all message headers.
2359 .It Ic ~U Ar messages
2360 Like `~m', but exclude all message headers.
2362 Invoke an alternate editor (defined by the
2364 option) on the message collected so far.
2365 Usually, the alternate editor will be a screen editor.
2366 After the editor is quit,
2367 the user may resume appending text to the end of the message.
2368 .It Ic ~w Ar filename
2369 Write the message onto the named file.
2371 the message is appended to it.
2373 Same as `~q', except that the message is not saved at all.
2374 .It Ic ~| Ar command
2375 Pipe the message through the specified filter command.
2376 If the command gives no output or terminates abnormally,
2377 retain the original text of the message.
2380 is often used as a rejustifying filter.
2384 .\" .Ss "Variable options" {{{
2385 .Ss "Variable options"
2386 Options are controlled via
2390 commands, see the corresponding entries for a syntax description.
2391 An option is also set if it is passed to \*(UA as part of the program
2392 environment (this is not restricted to specific variables as in the
2394 A value given in a startup file overrides a value imported from the
2396 Options may be either binary, in which case it is only significant to
2397 see whether they are set or not;
2398 or string, in which case the actual value is of interest.
2401 .\" .Ss "Binary options" {{{
2402 .Ss "Binary options"
2403 The binary options include the following:
2404 .Bl -tag -width ".Va autoprint"
2405 .It Va add-file-recipients
2406 When file or pipe recipients have been specified,
2407 mention them in the corresponding address fields of the message instead
2408 of silently stripping them from their recipient list.
2409 By default such addressees are not mentioned.
2411 Causes only the local part to be evaluated
2412 when comparing addresses.
2414 Causes messages saved in mbox to be appended to the end rather than
2416 This should always be set.
2417 .It Va ask Ns \ or Va asksub
2418 Causes \*(UA to prompt for the subject of each message sent.
2419 If the user responds with simply a newline,
2420 no subject field will be sent.
2422 Causes the prompts for `Cc:' and `Bcc:' lists to appear after the
2423 message has been edited.
2425 If set, \*(UA asks for files to attach at the end of each message.
2426 An empty line finalizes the list.
2428 Causes the user to be prompted for additional carbon copy recipients (at
2429 the end of each message if
2434 An empty line finalizes the list.
2436 Causes the user to be prompted for additional blind carbon copy
2437 recipients (at the end of each message if
2442 An empty line finalizes the list.
2444 \*(OP Causes the user to be prompted if the message is to be signed at
2445 the end of each message.
2448 variable is ignored when this variable is set.
2450 Causes threads to be collapsed automatically when threaded mode is
2455 Causes the delete command to behave like `dp -';
2456 thus, after deleting a message the next one will be typed automatically.
2458 Causes threaded mode (see the
2460 command) to be entered automatically when a folder is opened.
2462 Enables the substitution of `!' by the contents of the last command line
2464 .It Va batch-exit-on-error
2465 If the batch mode has been enabled via the
2467 command line option, then this variable will be consulted whenever \*(UA
2468 completes one operation (returns to the command prompt); if it is set
2469 then \*(UA will terminate if the last operation generated an error.
2471 Causes automatic display of a header summary after executing a
2475 Sets some cosmetical features to traditional BSD style;
2476 has the same affect as setting
2478 and all other variables prefixed with `bsd';
2479 it also changes the meaning of the \*(UA specific `\\&'
2483 Changes the letters printed in the first column of a header summary
2484 to traditional BSD style.
2486 Changes the display of columns in a header summary to traditional BSD
2489 Changes some informational messages to traditional BSD style.
2491 Causes the `Subject:' field to appear immediately after the `To:' field
2492 in message headers and with the `~h' tilde command.
2494 Changes the output format of the
2496 command to traditional BSD style.
2497 .It Va colour-disable
2498 \*(OP Forcefully disable usage of colours.
2499 Also see the section
2500 .Sx "Coloured message display" .
2502 Prints debugging messages and disables the actual delivery of messages.
2505 this option is intended for \*(UA development only.
2507 \*(OP When an IMAP mailbox is selected and this variable is set,
2508 no connection to the server is initiated.
2509 Instead, data is obtained from the local cache (see
2512 Mailboxes that are not present in the cache
2513 and messages that have not yet entirely been fetched from the server
2515 to fetch all messages in a mailbox at once,
2517 .Ns ` Ns Li copy * /dev/null Ns '
2518 can be used while still in
2521 Changes that are made to IMAP mailboxes in disconnected mode are queued
2522 and committed later when a connection to that server is opened in online
2524 This procedure is not completely reliable since it cannot be guaranteed
2525 that the IMAP unique identifiers (UIDs) on the server still match the
2526 ones in the cache at that time.
2529 when this problem occurs.
2530 .It Va disconnected-USER@HOST
2531 The specified account is handled as described for the
2534 but other accounts are not affected.
2536 The binary option dot causes \*(UA to interpret a period alone on a line
2537 as the terminator of a message the user is sending.
2539 If this variable is set then the editor is started automatically when
2540 composing a message in an interactive mode,
2541 as if the `~e' tilde command had been specified.
2544 variable is implied for this automatically spawned editor session.
2546 When a message is edited while being composed,
2547 its header is included in the editable text.
2548 The `To:', `Cc:', `Bcc:', `Subject:', `From:', `Reply-To:', `Sender:',
2549 and 'Organization:' fields are accepted within the header,
2550 other fields are ignored.
2552 If set, an empty mailbox file is not removed.
2553 This may improve the interoperability with other mail user agents
2554 when using a common folder directory.
2556 If the mailbox is empty \*(UA normally prints `No mail for user' and
2558 If this option is set \*(UA starts even with an empty mailbox.
2564 commands and vice-versa.
2565 .It Va forward-as-attachment
2566 Original messages are normally sent as inline text with the
2569 and only the first part of a multipart message is included.
2570 With this option messages are sent as MIME `message/rfc822' attachments
2571 with all of their parts included.
2576 options are ignored when the
2577 .Va forward-as-attachment
2580 When replying to a message \*(UA normally removes the comment parts of
2582 which by convention contain the full names of the recipients.
2583 If this variable is set such stripping is not performed,
2584 and comments are retained.
2586 Causes the header summary to be written at startup and after commands
2587 that affect the number of messages or the order of messages in the
2588 current folder; enabled by default.
2589 The command line option
2594 This option is used to hold messages in the system mailbox by default.
2596 \*(OP Can be used to turn off the automatic conversion of domain names
2597 according to the rules of IDNA (internationalized domain names for
2599 Since the IDNA code assumes domain names are specified with the
2601 character set, an UTF-8 locale charset is required to represent
2602 all possible international domain names (before conversion, that is).
2604 Ignore interrupt signals from the terminal while entering messages;
2605 instead echo them as `@' characters and discard the current line.
2607 An option related to
2611 which makes \*(UA refuse to accept a `control-D' as the end of a message.
2612 This option also applies to \*(UA command mode.
2613 .It Va imap-use-starttls
2614 \*(OP Causes \*(UA to issue a `STARTTLS' command to make an unencrypted
2615 IMAP session SSL/TLS encrypted.
2616 This functionality is not supported by all servers,
2617 and is not used if the session is already encrypted by the IMAPS method.
2618 .It Va imap-use-starttls-USER@HOST
2620 .Va imap-use-starttls
2621 for a specific account.
2623 This option causes \*(UA to truncate the user's system mailbox instead
2624 of deleting it when it is empty.
2625 This should always be set since it prevents malicious users from
2626 creating fake mail folders in a world-writable spool directory.
2628 When a message is saved it is usually discarded from the originating
2629 folder when \*(UA is quit.
2630 Setting this option causes all saved message to be retained.
2631 .It Va line-editor-disable
2632 Turn off any enhanced command line editing capabilities (see
2633 .Sx "Command line editor"
2636 When a message is replied to and this variable is set,
2637 it is marked as having been answered.
2638 This mark has no technical meaning in the mail system;
2639 it just causes messages to be marked in the header summary,
2640 and makes them specially addressable.
2641 .It Va message-id-disable
2642 By setting this option the generation of `Message-ID:' can be completely
2643 suppressed, effectively leaving this task up to the mail-transfer-agent
2644 (MTA) or the SMTP server.
2645 (According to RFC 5321 your SMTP server is not required to add this
2646 field by itself, so you should ensure that it accepts messages without
2649 Usually, when a group is expanded that contains the sender,
2650 the sender is removed from the expansion.
2651 Setting this option causes the sender to be included in the group.
2652 .It Va mime-allow-text-controls
2653 When sending messages, each part of the message is MIME-inspected in
2654 order to classify the `Content-Type:' and `Content-Transfer-Encoding:'
2655 that is required to send this part over mail transport, i.e.,
2656 a computation rather similar to what the
2658 command produces when used with the
2662 This classification however treats text files which are encoded in
2663 UTF-16 (often found for HTML files) and similar character sets as binary
2664 octet-streams, forcefully changing any `text/plain' or `text/html'
2665 specification to `application/octet-stream';
2666 if that actually happens, then a yet unset charset MIME parameter is set
2667 to `binary', effectively making it impossible for the receiving MUA to
2668 automatically interpret the contents of the part.
2670 If this option is set, and the data was unambiguously identified as text
2671 data at first glance (by a `.txt' or `.html' file extension), then the
2672 original `Content-Type:' will not be overwritten.
2673 .It Va mime-counter-evidence
2674 Normally the `Content-Type:' field is used to decide how to treat
2675 a messages MIME part.
2676 Some MUAs however don't use
2678 or a similar mechanism to correctly classify content,
2679 but simply specify `application/octet-stream',
2680 even for plain text attachments like `text/diff'.
2681 If this variable is set then \*(UA will use the file extension of
2682 attachments to classify such MIME message parts, if possible.
2684 Causes the filename given in the
2687 and the sender-based filenames for the
2691 commands to be interpreted relative to the directory given in the
2693 variable rather than to the current directory,
2694 unless it is set to an absolute pathname.
2696 If set, each message the
2698 command prints out is followed by a formfeed character.
2700 Send messages to the
2702 command without performing MIME and character set conversions.
2703 .It Va pop3-bulk-load
2704 \*(OP When accessing a POP3 server \*(UA loads the headers of the
2705 messages, and only requests the message bodies on user request.
2706 For the POP3 protocol this means that the message headers will be
2708 If this option is set then \*(UA will download only complete messages
2709 from POP3 servers instead.
2712 a macro that temporarily sets this option, then accesses a POP3 account
2713 that is known to only get small text messages, and then unsets this
2716 \*(OP Unless this variable is set the `APOP' authentication method
2717 will be used when connecting to a POP3 server that advertises support.
2718 The advantage of APOP over `USER/PASS' authentication is that the
2719 password is not sent in clear text over the wire and that only a single
2720 packet is sent for the user/password tuple.
2721 .It Va pop3-no-apop-HOST
2722 \*(IN Disables the `APOP' authentication method for a specific host.
2723 .It Va pop3-no-apop-USER@HOST
2724 Disables the `APOP' authentication method for a specific account.
2725 .It Va pop3-use-starttls
2726 \*(OP Causes \*(UA to issue a `STLS' command to make an unencrypted POP3
2727 session SSL/TLS encrypted.
2728 This functionality is not supported by all servers,
2729 and is not used if the session is already encrypted by the POP3S method.
2730 .It Va pop3-use-starttls-HOST
2732 .Va pop3-use-starttls
2733 for a specific host.
2734 .It Va pop3-use-starttls-USER@HOST
2736 .Va pop3-use-starttls
2737 for a specific account.
2738 .It Va print-all-chars
2739 This option causes all characters to be considered printable.
2740 It is only effective if given in a startup file.
2741 With this option set some character sequences in messages may put the
2742 user's terminal in an undefined state when printed;
2743 it should only be used as a last resort if no working system locale can
2745 .It Va print-alternatives
2746 When a MIME message part of type `multipart/alternative' is displayed
2747 and it contains a subpart of type `text/plain',
2748 other parts are normally discarded.
2749 Setting this variable causes all subparts to be displayed,
2750 just as if the surrounding part was of type `multipart/mixed'.
2752 Suppresses the printing of the version when first invoked.
2753 .It Va quote-as-attachment
2754 If this is set, then the original message is added in its entirety
2755 as a `message/rfc822' MIME attachment when replying to a message.
2756 Note this works regardless of the setting of
2758 .It Va recipients-in-cc
2759 On group replies, specify only the sender of the original mail in `To:'
2760 and mention it's other recipients in the secondary `Cc:'.
2761 .It Va record-resent
2762 If both this variable and the
2769 commands save messages to the
2771 folder as it is normally only done for newly composed messages.
2772 .It Va reply-in-same-charset
2773 If this variable is set \*(UA first tries to use the same character set
2774 of the original message for replies.
2775 If this fails, the mechanism described in
2776 .Sx "Character sets"
2777 is evaluated as usual.
2779 Reverses the sense of
2784 .It Va rfc822-body-from_
2785 This variable can be used to force the display of a so-called `From_'
2786 line for messages that are embedded into an envelope mail via the
2787 `message/rfc822' MIME mechanism.
2789 When the user aborts a message with two `RUBOUT' (interrupt,
2790 `control-C') characters,
2791 \*(UA will copy the partial letter to the file
2793 This option is set by default.
2794 .It Va searchheaders
2795 Expand message-list specifiers in the form `/x:y' to all messages
2796 containing the substring `y' in the header field `x'.
2797 The string search is case insensitive.
2798 .It Va sendcharsets-else-ttycharset
2799 \*(OP If this variable is set, but
2801 is not, then \*(UA acts as if
2803 had been set to the value of the variable
2805 In effect this combination passes through the message data in the
2806 character set of the current locale (given that
2808 hasn't been set manually), i.e., without converting it to the
2810 fallback character set.
2811 Thus, mail message text will be in `ISO-8859-1' encoding when send from
2812 within a `ISO-8859-1' locale, and in `UTF-8' encoding when send from
2813 within an `UTF-8' locale.
2814 If no character set conversion capabilities are available in \*(UA then
2815 the only supported character set is
2818 When sending a message wait until the MTA exits before accepting further
2820 If the MTA returns a non-zero exit status,
2821 the exit status of \*(ua will also be non-zero.
2823 Setting this option causes \*(UA to start at the last message instead of
2824 the first one when opening a mail folder.
2826 Causes \*(UA to use the sender's real name instead of the plain address
2827 in the header field summary and in message specifications.
2829 Causes the recipient of the message to be shown in the header summary
2830 if the message was sent by the user.
2831 .It Va skipemptybody
2832 If an outgoing message does not contain any text in its first or only
2834 do not send it but discard it silently (see also the command line option
2837 .It Va smime-force-encryption
2838 \*(OP Causes \*(UA to refuse sending unencrypted messages.
2840 \*(OP S/MIME sign outgoing messages with the user's private key and
2841 include the user's certificate as a MIME attachment.
2842 Signing a message enables a recipient to verify that the sender used
2843 a valid certificate,
2844 that the email addresses in the certificate match those in the message
2845 header and that the message content has not been altered.
2846 It does not change the message text,
2847 and people will be able to read the message as usual.
2851 .Va smime-sign-include-certs .
2852 .It Va smime-no-default-ca
2853 \*(OP Don't load default CA locations when verifying S/MIME signed
2855 .It Va smtp-use-starttls
2856 \*(OP Causes \*(UA to issue a `STARTTLS' command to make an SMTP session
2858 Not all servers support this command \(en because of common
2859 implementation defects it can't be automatically determined whether
2860 a server supports it or not.
2861 .It Va ssl-no-default-ca
2862 \*(OP Don't load default CA locations to verify SSL/TLS server
2865 \*(OP Accept SSLv2 connections.
2866 These are normally not allowed because this protocol version is insecure.
2867 .It Va keep-content-length
2868 When (editing messages and) writing MBOX mailbox files \*(UA can be told
2869 to keep the `Content-Length:' and `Lines:' header fields that some MUAs
2870 generate by setting this variable.
2871 Since \*(UA does neither use nor update these non-standardized header
2872 fields (which in itself shows one of their conceptual problems),
2873 stripping them should increase interoperability in between MUAs that
2874 work with with same mailbox files.
2875 Note that, if this is not set but
2876 .Va writebackedited ,
2877 as below, is, a possibly performed automatic stripping of these header
2878 fields already marks the message as being modified.
2880 Setting this option enables upward compatibility with \*(UA version 15.0
2881 in respect to which configuration options are available and how they are
2883 This manual uses \*(IN and \*(OU to refer to the new and the old way of
2884 doing things, respectively.
2886 Setting this option, also controllable via the command line option
2888 causes \*(UA to be more verbose, so that, e.g., certificate chains will
2889 be displayed on the users terminal.
2890 Setting this binary options twice increases the level of verbosity, in
2891 which case even details of the actual message delivery and protocol
2892 conversations are also shown.
2895 is sufficient to disable verbosity as such.
2896 .It Va writebackedited
2897 If this variable is set messages modified using the
2901 commands are written back to the current folder when it is quit;
2902 it is only honoured for writable folders in `mbox' format, though.
2903 Note that the editor will be pointed to the raw message content in that
2904 case, i.e., neither MIME decoding nor decryption will have been
2906 and proper RFC 4155 `From ' quoting of newly added or edited content is
2907 also left as an excercise to the user.
2911 .\" .Ss "Value options" {{{
2913 The value options include the following:
2914 .Bl -tag -width ".Va autoprint"
2916 A sequence of characters to print in the `attribute' column of a header
2918 each for one type of messages in the following order:
2919 new (N), unread but old (U), new but read (R), read and old (O), saved
2920 (S), preserved (P), mboxed (M), flagged (F), answered (A), draft (T),
2921 start of a collapsed thread (+), collapsed (\-), classified as spam ($).
2922 The default is `NUROSPMFAT+\-$',
2923 or `NU\ \ *HMFAT+\-$' if
2927 environment variable are set.
2929 Specifies a list of recipients to which a blind carbon copy of each
2930 outgoing message will be sent automatically.
2932 Specifies a list of recipients to which a carbon copy of each outgoing
2933 message will be sent automatically.
2935 Causes sorted mode (see the
2937 command) to be entered automatically with the value of this option as
2938 sorting method when a folder is opened.
2940 The value that should appear in the `charset=' parameter of
2941 `Content-Type:' MIME header fields when no character set conversion of
2942 the message data was performed.
2943 This defaults to `US-ASCII', and the chosen character set should be
2944 `US-ASCII' compatible.
2946 \*(OP The default 8 bit character set that is used as an implied last
2947 member of the variable
2949 Defaults to `UTF-8'.
2950 If no character set conversion capabilities are available in \*(UA then
2951 the only supported character set is
2953 Refer to the section
2954 .Sx "Character sets"
2955 for the complete picture of character set conversion in \*(UA.
2957 The default value for the
2961 \*(OP The colour specification for so-called `From_' lines.
2963 .Sx "Coloured message display"
2964 for the format of the value.
2965 .It Va colour-header
2966 \*(OP The colour specification for header lines.
2968 .Sx "Coloured message display"
2969 for the format of the value.
2970 .It Va colour-msginfo
2971 \*(OP The colour specification for the introductional message info line.
2973 .Sx "Coloured message display"
2974 for the format of the value.
2975 .It Va colour-pagers
2976 \*(OP A comma-separated list of
2978 s for which coloured message display can be used.
2979 Note that only a substring comparison is performed, meaning that the
2980 string `lesser' will match the string `less'.
2982 .Sx "Coloured message display"
2984 The default is set to the sole string `less'.
2985 .It Va colour-partinfo
2986 \*(OP The colour specification for MIME part info lines.
2988 .Sx "Coloured message display"
2989 for the format of the value.
2991 \*(OP A comma-separated list of
2993 inals for which coloured message display can be used.
2996 .Dl cons25,linux,rxvt,rxvt-unicode,\:screen,\:sun,\:vt100,\:vt220,\:\
2997 wsvt25,\:xterm,\:xterm-color
2998 .It Va colour-uheader
2999 \*(OP The colour specification for those header lines that have been
3001 .Va colour-user-headers
3004 .Sx "Coloured message display"
3005 for the format of the value.
3006 .It Va colour-user-headers
3007 A comma separated list of (case-insensitive) header names which should
3008 be colourized with the alternative
3011 The default value is `from,subject'.
3013 The valued option crt is used as a threshold to determine how long
3014 a message must be before
3019 is set without a value then the height of the terminal screen stored in
3020 the system is used to compute the threshold (see
3026 The name of the file to use for saving aborted messages.
3027 This defaults to `dead.letter' in the user's home directory.
3029 The date in a header summary is normally the date of the mailbox `From\ '
3030 line of the message.
3031 If this variable is set, then the date as given in the `Date:' field is
3032 used, converted to local time.
3033 It is possible to control the display of the date by assigning a value,
3036 function will be used to format the date accordingly.
3037 Please read your system manual for the available formats.
3038 Note that the `%n' format should not be used, because \*(UA doesn't
3039 take embedded newlines into account when calculating how many lines fit
3041 .It Va datefield-markout-older
3042 This option, when set in addition to
3044 modifies the display of messages that are not really current in a way
3045 that is rather comparable to the
3050 The interpretation of the value is identical to what has been described
3054 Pathname of the text editor to use in the
3059 A default editor is used if this value is not defined.
3061 Suggestion for the MIME encoding to use in outgoing text messages
3063 Valid values are the default `quoted-printable', `8bit' and `base64'.
3064 `8bit' may cause problems with when transferring mail messages over
3065 channels that are not ESMTP (RFC 1869) compliant.
3066 If there is no need to encode a message,
3067 `7bit' transfer mode is always used regardless of this variable.
3068 Binary data is always encoded as `base64'.
3070 If defined, the first character of this option
3071 gives the character to use in place of `~' to denote tilde escapes.
3073 The name of the directory to use for storing folders of messages.
3074 All folder names that begin with `+' refer to files below it.
3075 The same special conventions as documented for the
3077 command may be used when specifying a new value for
3079 but be aware that the expansion is fully performed immediately.
3080 E.g., if the expanded name refers to an IMAP account, all names that
3081 begin with `+' refer to IMAP mailboxes below the
3085 Note: some IMAP servers do not accept the creation of mailboxes in
3086 the hierarchy base, but require that they are created as subfolders of
3087 `INBOX' \(en with such servers a folder name of the form
3089 .Dl imaps://mylogin@imap.myisp.example/INBOX.
3091 should be used (the last character is the server's hierarchy delimiter).
3092 Folder names prefixed by `+' will then refer to folders below `INBOX',
3093 while folder names prefixed by `@' refer to folders below the hierarchy
3097 namespace command for a method to detect the appropriate prefix and
3100 When a folder is opened and this variable is set,
3101 the macro corresponding to the value of this variable is executed.
3102 The macro is also invoked when new mail arrives,
3103 but message lists for commands executed from the macro
3104 only include newly arrived messages then.
3105 .It Va folder-hook-fullname
3106 When a folder named `fullname' is opened,
3107 the macro corresponding to the value of this variable is executed.
3108 Unlike other folder specifications,
3109 the fully expanded name of a folder, without metacharacters,
3110 is used to avoid ambiguities.
3111 The macro specified with
3113 is not executed if this variable is effective for a folder
3116 ed from within the actually executed macro).
3118 The address (or a list of addresses) to put into the `From:' field of
3119 the message header, quoting RFC 5322:
3120 the author(s) of the message, that is, the mailbox(es) of the person(s)
3121 or system(s) responsible for the writing of the message.
3122 If replying to messages these addresses are handled as if they were in
3126 If the machine's hostname is not valid at the Internet (for example at
3127 a dialup machine) then either this variable or
3132 adds even more fine-tuning capabilities),
3136 contains more than one address,
3139 variable is required (according to the standard RFC 5322).
3141 The string to print before the text of a message with the
3145 .Va forward-as-attachment
3147 Defaults to `-------- Original Message --------' if unset.
3148 No heading is printed if it is set to the empty string.
3150 A format string to use for the header summary,
3154 A `%' character introduces a format specifier.
3155 It may be followed by a number indicating the field width.
3156 If the (possibly implicitly implied) field width is negative, the field
3157 is to be left-aligned.
3158 Valid format specifiers are:
3159 .Bl -tag -offset indent -width "%%"
3163 The date when the message was received.
3165 The indenting level in threaded mode.
3167 The address of the message sender.
3169 The message thread structure.
3170 (Note that this format doesn't support a field width.)
3172 The number of lines of the message.
3176 The number of octets (bytes) in the message.
3178 Message subject (if any).
3180 Message subject (if any) in double quotes.
3182 The position in threaded/sorted order.
3184 A `>' for the current message, otherwise ` '.
3186 A `<' for the current message, otherwise ` '.
3188 The spam score of the message, as has been classified via the command
3194 The default is `%>\&%a\&%m\ %-18f\ %16d\ %4l/%\-5o\ %i%-s',
3195 or `%>\&%a\&%m\ %20-f\ \ %16d\ %3l/%\-5o\ %i%-S' if
3199 Use this string as hostname when expanding local addresses instead of
3200 the value obtained from
3204 i.e., in `Message-ID:' and `From:' fields.
3207 transport is not used then it is normally the responsibility of the MTA
3208 to create these fields, \*(IN in conjunction with
3212 also influences the results;
3213 you should produce some test messages with the desired combination of
3220 \*(OP Sets the IMAP authentication method.
3221 Valid values are `login' for the usual password-based authentication
3223 `cram-md5', which is a password-based authentication that does not send
3224 the password over the network in clear text,
3225 and `gssapi' for GSS-API based authentication.
3226 .It Va imap-auth-USER@HOST
3227 Sets the IMAP authentication method for a specific account.
3229 \*(OP Enables caching of IMAP mailboxes.
3230 The value of this variable must point to a directory that is either
3231 existent or can be created by \*(UA.
3232 All contents of the cache can be deleted by \*(UA at any time;
3233 it is not safe to make assumptions about them.
3234 .It Va imap-keepalive
3235 \*(OP IMAP servers may close the connection after a period of
3236 inactivity; the standard requires this to be at least 30 minutes,
3237 but practical experience may vary.
3238 Setting this variable to a numeric `value' greater than 0 causes
3239 a `NOOP' command to be sent each `value' seconds if no other operation
3241 .It Va imap-list-depth
3242 \*(OP When retrieving the list of folders on an IMAP server, the
3244 command stops after it has reached a certain depth to avoid possible
3246 The value of this variable sets the maximum depth allowed.
3248 If the folder separator on the current IMAP server is a slash `/',
3249 this variable has no effect and the
3251 command does not descend to subfolders.
3253 String used by the `~m' and `~M' tilde escapes and by the
3255 option for indenting messages,
3256 in place of the normal tab character (`^I').
3257 Be sure to quote the value if it contains spaces or tabs.
3259 Pathname of the directory lister to use in the
3261 command when operating on local mailboxes.
3264 .It Va line-editor-cursor-right
3265 \*(OP If the builtin command line editor is used, actions which are
3266 based on rightwise movement may not work on some terminals.
3267 If you encounter such problems, set this variable to the terminal
3268 control sequence that is necessary to move the cursor one column to the
3270 The default is `\\033[C', which should work for most terminals.
3271 Less often occur `\\033OC' and `\\014'.
3272 Note that `ESCAPE' and other control character have to be written as
3273 shell-style escape sequences, e.g., `\\033' for `ESCAPE'.
3275 Is used as the user's mailbox, if set.
3276 Otherwise, a system-dependent default is used.
3277 Supports a logical subset of the special conventions that are documented
3284 The name of the mbox file.
3285 Supports a logical subset of the special conventions that are documented
3291 The fallback default is `mbox' in the user's home directory.
3292 .It Va mimetypes-load-control
3293 This option can be used to control which of the
3295 MIME type databases are loaded by \*(UA.
3296 If the letter `u' (or `U') is part of this options value, then the
3299 file will be loaded (if it exists);
3300 likewise the letter `s' (or `S') controls loading of the system wide
3301 .Pa /etc/mime.types .
3302 If this option is not set \*(UA will try to load both files instead.
3303 Incorporation of the MIME types that are compiled into \*(UA cannot be
3305 .It Va NAIL_EXTRA_RC
3306 The name of an optional startup file to be read after \*(ur.
3307 This variable is ignored if it is imported from the environment;
3308 it has an effect only if it is set in \*(UR or \*(ur to allow bypassing
3309 the configuration with, e.g., `MAILRC=/dev/null'.
3310 Use this file for commands that are not understood by other \*(UA
3313 A string to put at the beginning of each new message.
3314 The escape sequences `\et' (tabulator) and `\en' (newline) are understood.
3315 .It Va NAIL_HISTFILE
3316 \*(OP If a command line editor is available then this can be set to
3317 name the (expandable) path of the location of a permanent history file.
3318 .It Va NAIL_HISTSIZE
3319 \*(OP If a command line editor is available this value restricts the
3320 amount of history entries that are saved into a set and valid
3322 A value of less than 0 disables this feature;
3323 note that loading and incorporation of
3325 upon program startup can also be suppressed by doing this.
3326 An unset or invalid value, or 0, causes a default value to be used.
3327 Dependent on the available command line editor this will also define the
3328 number of history entries in memory;
3329 it is also editor-specific wether runtime updates of this value will be
3332 A string to put at the end of each new message.
3333 The escape sequences `\et' (tabulator) and `\en' (newline) are understood.
3335 If this variable has the value `maildir',
3336 newly created local folders will be in `maildir' format.
3338 Checks for new mail in the current folder each time the prompt is
3340 For IMAP mailboxes the server is then polled for new mail,
3341 which may result in delayed operation if the connection to the server is
3343 A `maildir' folder must be re-scanned to determine if new mail has
3346 If this variable is set to the special value `nopoll' an IMAP server is
3347 not actively asked for new mail,
3348 but new mail may still be detected and announced with any other IMAP
3349 command that is sent to the server.
3350 A `maildir' folder is not scanned, then.
3352 In either case the IMAP server may send notifications about messages
3353 that have been deleted on the server by another process or client.
3354 In this case, `Expunged X messages' is printed regardless of this
3356 and message numbers may have changed.
3358 The value to put into the `Organization:' field of the message header.
3360 Pathname of the program to use in the more command or when the
3363 The default paginator is
3366 \*(IN Sets a global fallback password, which is used in case none has
3367 been given in the protocol and account-specific URL and neither is there
3368 a matching `password-USER@HOST' nor a matching `password-HOST';
3369 as a last resort \*(UA will ask for a password on the user's terminal if
3370 the authentication method requires a password.
3371 Specifying passwords in a startup file is generally a security risk;
3372 the file should be readable by the invoking user only.
3373 .It Va password-HOST
3376 for accounts on a specific host.
3377 .It Va password-USER@HOST
3382 for a specific account.
3384 Set the password for `user' when connecting to `host'.
3385 If no such variable is defined for a host,
3386 the user will be asked for a password on standard input.
3387 Specifying passwords in a startup file is generally a security risk;
3388 the file should be readable by the invoking user only.
3389 .It Va pipe-content/subcontent
3390 When a MIME message part of `content/subcontent' type is displayed or
3392 its text is filtered through the value of this variable interpreted as
3395 The special value `@' can be used to force interpretation of the message
3396 part as plain text, e.g., `set pipe-application/pgp-signature=@' will
3397 henceforth treat signatures as plain text and display them "as is".
3399 Also, if a normal shell command is prefixed with `@', then the command
3400 will only be used to prepare the MIME message part if the message is
3401 displayed by itself, but not when multiple messages are displayed at
3404 Finally, if a normal shell command is prefixed with `@&', then, in
3405 addition to what has been described for the plain `@' shell command
3406 prefix, the command will be run asynchronously, i.e., without blocking
3407 \*(UA, which may be a handy way to display a, e.g., PDF file while also
3408 continuing to read the mail message.
3410 Special care must be taken when using such commands as mail viruses may
3411 be distributed by this method;
3412 if messages of type `application/x-sh' were filtered through the shell,
3414 a message sender could easily execute arbitrary code on the system \*(UA
3416 .It Va pop3-keepalive
3417 \*(OP POP3 servers close the connection after a period of inactivity;
3418 the standard requires this to be at least 10 minutes,
3419 but practical experience may vary.
3420 Setting this variable to a numeric `value' greater than 0 causes
3421 a `NOOP' command to be sent each `value' seconds if no other operation
3424 The string printed when a command is accepted.
3425 Prompting may be prevented by either setting this to the null string
3428 The same XSI escape sequences that are understood by the
3430 command may be used within
3433 In addition, the following \*(UA specific additional sequences are
3435 `\\&', which expands to `?' unless
3437 is set, in which case it expands to `&';
3438 note that "\\& " is the default value for
3440 `\\?', which will expand to `1' if the last command failed, and to `0'
3442 `\\$', which will expand to the name of the currently active
3444 if any, and to the empty string otherwise,
3445 and `\\@', which will expand to the name of the currently active mailbox.
3446 (Note that the prompt buffer is size-limited, excess is cut off.)
3448 When a newer version of the
3450 .Sx "Command line editor"
3451 is used, any escape sequence must itself be encapsulated with another
3452 escape character for usage with the
3454 mechanism: \*(UA configures the control character `\\01' for this.
3456 If set, \*(UA starts a replying message with the original message
3457 prefixed by the value of the variable
3459 Normally, a heading consisting of `Fromheaderfield wrote:' is printed
3460 before the quotation.
3461 If the string `noheading' is assigned to the
3463 variable, this heading is omitted.
3464 If the string `headers' is assigned, the headers selected by the
3465 .Ic ignore Ns / Ns Ic retain
3466 commands are printed above the message body,
3469 acts like an automatic `~m' tilde escape command, then.
3470 If the string `allheaders' is assigned, all headers are printed above
3471 the message body and all MIME parts are included,
3474 act like an automatic `~M' command.
3476 .Va quote-as-attachment .
3478 \*(OP Can be set in addition to
3480 Setting this turns on a more fancy quotation algorithm in that leading
3481 quotation characters are compressed and overlong lines are folded.
3483 can be set to either one or two (space separated) numeric values,
3484 which are interpreted as the maximum (goal) and the minimum line length,
3485 respectively, in a spirit rather equal to the
3487 program, but line-, not paragraph-based.
3488 If not set explicitly the minimum will reflect the goal algorithmically.
3489 The goal can't be smaller than the length of
3491 plus some additional pad.
3492 Necessary adjustments take place silently.
3494 If defined, gives the pathname of the folder used to record all outgoing
3496 If not defined, then outgoing mail is not saved.
3497 When saving to this folder fails the message is not sent,
3498 but instead saved to
3501 A list of addresses to put into the `Reply-To:' field of the message
3503 Members of this list are handled as if they were in the
3507 When \*(UA initially prints the message headers it determines the number
3508 to print by looking at the speed of the terminal.
3509 The faster the terminal, the more it prints.
3510 This option overrides this calculation and specifies how many message
3511 headers are printed.
3512 This number is also used for scrolling with the
3516 \*(OP A comma-separated list of character set names that can be used in
3517 outgoing Internet mail.
3518 The value of the variable
3520 is automatically appended to this list of character-sets.
3521 If no character set conversion capabilities are compiled into \*(UA then
3522 the only supported charset is
3525 .Va sendcharsets-else-ttycharset
3526 and refer to the section
3527 .Sx "Character sets"
3528 for the complete picture of character set conversion in \*(UA.
3530 An address that is put into the `Sender:' field of outgoing messages,
3531 quoting RFC 5322: the mailbox of the agent responsible for the actual
3532 transmission of the message.
3533 This field should normally not be used unless the `From:' field contains
3534 more than one address, on which case it is required.
3537 address is handled as if it were in the
3541 To use an alternate mail delivery system,
3542 set this option to the full pathname of the program to use.
3543 It may be necessary to set
3544 .Va sendmail-progname
3546 .It Va sendmail-progname
3547 Many systems use a so-called
3549 environment to ensure compatibility with
3551 This works by inspecting the name that was used to invoke the mail
3553 If this variable is set then the mailwrapper (the program that is
3554 actually executed when calling `sendmail') will treat its contents as
3556 The default is `sendmail'.
3558 Pathname of the shell to use in the
3560 command and the `~!' tilde escape.
3561 A default shell is used if this option is not defined.
3563 A string for use with the `~A' tilde escape.
3565 A string for use with the `~a' tilde escape.
3567 Must correspond to the name of a readable file if set.
3568 The file's content is then appended to each singlepart message
3569 and to the first part of each multipart message.
3570 Be warned that there is no possibility to edit the signature for an
3573 \*(OP Specifies a directory with CA certificates in PEM (Privacy
3574 Enhanced Mail) format for verification of S/MIME signed messages.
3575 .It Va smime-ca-file
3576 \*(OP Specifies a file with CA certificates in PEM format for
3577 verification of S/MIME signed messages.
3578 .It Va smime-cipher-USER@HOST
3579 \*(OP Specifies a cipher to use when generating S/MIME encrypted
3580 messages for the specified account.
3581 RFC 5751 mandates a default of `aes-128' (AES-128 CBC).
3583 The actually available cipher algorithms depend on the cryptographic
3584 library that \*(UA uses; possible values are, in decreasing cipher
3586 `aes-256' (AES-256 CBC), `aes-192' (AES-192 CBC), `aes-128' (AES-128 CBC),
3587 `des3' (DES EDE3 CBC, 168 bits; default if `aes-128' isn't available)
3588 and `des' (DES CBC, 56 bits).
3590 The following ciphers have been obsoleted and are no longer mentioned by
3591 the S/MIME specification (RFC 5751), but may be selected if available:
3592 `rc2-64' (RC2 CBC, 64 bits) and `rc2-40' (RC2 CBC, 40 bits).
3593 .It Va smime-crl-file
3594 \*(OP Specifies a file that contains a CRL in PEM format to use when
3595 verifying S/MIME messages.
3596 .It Va smime-crl-dir
3597 \*(OP Specifies a directory that contains files with CRLs in PEM format
3598 to use when verifying S/MIME messages.
3599 .It Va smime-encrypt-USER@HOST
3600 \*(OP If this variable is set, messages send to the given receiver are
3601 encrypted before sending.
3602 The value of the variable must be set to the name of a file that
3603 contains a certificate in PEM format.
3605 If a message is sent to multiple recipients,
3606 each of them for whom a corresponding variable is set will receive an
3607 individually encrypted message;
3608 other recipients will continue to receive the message in plain text
3610 .Va smime-force-encryption
3612 It is recommended to sign encrypted messages, i.e., to also set the
3615 .It Va smime-sign-cert
3616 \*(OP Points to a file in PEM format.
3617 For the purpose of signing and decryption this file needs to contain the
3618 user's private key as well as his certificate.
3620 For the purpose of encryption the recipient's public encryption key
3621 (certificate) is expected; the command
3623 can be used to save certificates of signed messages (the section
3624 .Sx "Signed and encrypted messages with S/MIME"
3625 gives some details).
3626 This mode of operation is usually driven via
3627 .Va smime-sign-cert-USER@HOST ,
3629 .It Va smime-sign-cert-USER@HOST
3632 for a specific account.
3633 For message signing `USER@HOST' is always derived from the value of
3635 (or, if that contains multiple addresses,
3639 When decrypting messages the account is derived from the recipient
3640 fields (`To:' and `Cc:') of the message, which are searched for
3641 addresses for which such a variable is set.
3642 \*(UA always uses the first address that matches,
3643 so if the same message is sent to more than one of the user's addresses
3644 using different encryption keys, decryption might fail.
3645 .It Va smime-sign-include-certs
3646 \*(OP If used, this is supposed to a consist of a comma-separated list
3647 of files, each of which containing a single certificate in PEM format to
3648 be included in the S/MIME message in addition to the
3651 This is most useful for long certificate chains if it is desired to aid
3652 the receiving party's verification process.
3653 Note that top level certificates may also be included in the chain but
3654 don't play a role for verification.
3658 .Va smime-sign-cert-USER@HOST .
3659 .It Va smime-sign-include-certs-USER@HOST
3661 .Va smime-sign-include-certs
3662 for a specific account.
3664 \*(OP Normally \*(UA invokes the program defined via
3666 to transfer messages.
3669 variable will instead cause `SMTP' network connections be made to the
3670 server specified therein in order to directly submit the message.
3671 \*(UA knows about three different "SMTP protocols":
3672 .Bl -bullet -offset indent
3674 The plain `SMTP' protocol (RFC 5321) that normally lives on the
3675 server port 25 and requires setting of the
3676 .Va smtp-use-starttls
3677 variable as above to enter a SSL/TLS encrypted session state.
3678 Assign a value like \*(IN `[smtp://][user[:password]@]server[:port]'
3679 (\*(OU `[smtp://]server[:port]')
3680 to choose this protocol.
3682 Then the so-called `SMTPS' which is supposed to live on server port 465
3683 and is automatically SSL/TLS secured.
3684 Unfortunately it never became a standardized protocol and may thus not
3685 be supported by your hosts network service database
3686 \(en in fact the port number has already been reassigned to other
3689 `SMTPS' is nonetheless a commonly offered "protocol" and thus can be
3690 chosen by assigning a value like \*(IN
3691 `smtps://[user[:password]@]server[:port]'
3692 (\*(OU `smtps://server[:port]');
3693 due to the mentioned problems it is usually necessary to explicitly
3694 specify the port as `:465', however.
3696 Finally there is the `SUBMISSION' protocol (RFC 6409), which usually
3697 lives on server port 587 and is practically identically to the `SMTP'
3698 protocol from \*(UAs point of view beside that; it requires setting the
3699 .Va smtp-use-starttls
3700 variable to enter a SSL/TLS secured session state.
3701 Assign a value like \*(IN `submission://[user[:password]@]server[:port]'
3702 (\*(OU `submission://server[:port]').
3705 \*(IN If `user' or `password' contain special characters, in particular
3706 whitespace, `/', `:' or `%', they must be specified in URL notation
3709 may be helpful for preparation).
3711 The SMTP transfer is executed in a child process, which runs
3712 asynchronously unless either the
3717 If it receives a TERM signal, it will abort and save the message to
3720 \*(OP Sets the SMTP authentication method.
3721 Possible values are `none' (the default), `plain', `login'
3722 as well as the \*(OPal methods `cram-md5' and `gssapi'.
3723 The `none' method doesn't need any user credentials,
3724 `gssapi' requires a user name
3725 and all other methods require a user name and a password.
3732 .Va smtp-auth-password
3734 .Va smtp-auth-user Ns
3736 .It Va smtp-auth-HOST
3739 for SMTP accounts on a specific host.
3740 .It Va smtp-auth-USER@HOST
3743 for a specific account.
3744 (\*(OU For specific values of sender addresses, dependend upon the variable
3747 .It Va smtp-auth-password
3748 \*(OP \*(OU Sets the global fallback password for SMTP authentication.
3749 If the authentication method requires a password, but neither
3750 .Va smtp-auth-password
3752 .Va smtp-auth-password-USER@HOST
3754 \*(UA will ask for a password on the user's terminal.
3755 .It Va smtp-auth-password-USER@HOST
3757 .Va smtp-auth-password
3758 for specific values of sender addresses, dependent upon the variable
3760 .It Va smtp-auth-user
3761 \*(OP \*(OU Sets the global fallback user name for SMTP authentication.
3762 If the authentication method requires a user name, but neither
3765 .Va smtp-auth-user-USER@HOST
3767 \*(UA will ask for a user name on the user's terminal.
3768 .It Va smtp-auth-user-USER@HOST
3771 for specific values of sender addresses, dependent upon the variable
3773 .It Va smtp-hostname
3774 \*(IN Normally \*(UA uses the variable
3776 to derive the necessary `USER@HOST' information to issue a
3777 `MAIL FROM:<>' SMTP command.
3780 can be used to use the `USER' from the SMTP account
3785 and the `HOST' from the content of this variable
3786 (or, if that is the empty string,
3788 or the local hostname as a last resort).
3789 Setting this variable also influences the generated `Message-Id:'.
3791 \*(OP The path to the spam detector.
3792 Note that the path is not expanded, but used "as is".
3793 A fallback path will have been compiled into the \*(UA binary if the
3795 executable had been found during compilation.
3797 \*(OP Can be used to specify the host on which
3799 listens for connections; if not set, defaults to `localhost'.
3801 \*(OP Spam detectors like
3803 decline to work with messages which exceed a specific size;
3804 if this variable is set then \*(UA won't even try to pass messages which
3805 exceed the given limit.
3806 The default is 420000 bytes.
3808 \*(OP Can be used to explicitly specify the port on which
3810 listens for connections.
3812 \*(OP If the spam detector listens on a path-based UNIX domain socket,
3813 then setting this variable to the fully qualified path will force its
3814 usage for communication.
3816 \*(OP This can be used to support multiple, per-used configuration files
3817 of the spam detector.
3818 Note that \*(UA doesn't automatically set this to reflect a possibly set
3822 \*(OP Specifies a directory with CA certificates in PEM (Pricacy
3823 Enhanced Mail) for verification of of SSL/TLS server certificates.
3825 .Xr SSL_CTX_load_verify_locations 3
3826 for more information.
3828 \*(OP Specifies a file with CA certificates in PEM format for
3829 verification of SSL/TLS server certificates.
3831 .Xr SSL_CTX_load_verify_locations 3
3832 for more information.
3834 \*(OP Sets the file name for a SSL/TLS client certificate required by
3836 .It Va ssl-cert-USER@HOST
3837 Sets an account-specific file name for a SSL/TLS client certificate
3838 required by some servers.
3841 for the specified account.
3842 .It Va ssl-cipher-list
3843 \*(OP Specifies a list of ciphers for SSL/TLS connections.
3846 for more information.
3848 \*(OP Specifies a file that contains a CRL in PEM format to use when
3849 verifying SSL/TLS server certificates.
3851 \*(OP Specifies a directory that contains files with CRLs in PEM format
3852 to use when verifying SSL/TLS server certificates.
3854 \*(OP Sets the file name for the private key of a SSL/TLS client
3856 If unset, the name of the certificate file is used.
3857 The file is expected to be in PEM format.
3858 .It Va ssl-key-USER@HOST
3859 Sets an account-specific file name for the private key of a SSL/TLS
3863 for the specified account.
3865 \*(OP Selects the used TLS/SSL protocol version.
3866 The actually available protocol versions depend on the TLS/SSL
3867 library that \*(UA uses; possible values are, from newest to oldest:
3868 `tls1.2', `tls1.1', `tls1', `ssl3' and `ssl2'.
3872 to any of these values will fixate the used protocol, which means that
3873 connections will fail if the server doesn't support it.
3874 The value `auto', which is the default, chooses a compatibility method
3875 that automatically uses the newest protocol version that the server
3876 is capable to understand.
3878 It has to be noted that `auto' is used as a fallback method if
3879 the actual setting of
3881 isn't supported by the used TLS/SSL library \(em in this case an error
3882 message will be printed first, however.
3883 .It Va ssl-method-USER@HOST
3886 for a specific account.
3888 \*(OP Gives the pathname to an entropy daemon socket, see
3890 .It Va ssl-rand-file
3891 \*(OP Gives the pathname to a file with entropy data, see
3892 .Xr RAND_load_file 3 .
3893 If the file is a regular file writable by the invoking user,
3894 new data is written to it after it has been loaded.
3896 \*(OP Sets the action to be performed if an error occurs during SSL/TLS
3897 server certificate validation.
3899 `strict' (fail and close connection immediately),
3900 `ask' (ask whether to continue on standard input),
3901 `warn' (print a warning and continue),
3902 `ignore' (do not perform validation).
3903 The default is `ask'.
3904 .It Va ssl-verify-USER@HOST
3907 for a specific account.
3909 If only set without an assigned value, then this option inhibits the
3910 generation of the `Message-Id:' and `User-Agent:' header fields that
3911 include obvious references to \*(UA.
3912 There are two pitfalls associated with this:
3913 First, the message id of outgoing messages is not known anymore.
3914 Second, an expert may still use the remaining information in the header
3915 to track down the originating mail user agent.
3916 If set to the value `noagent', then the mentioned `Message-Id:'
3917 suppression doesn't occur.
3919 If defined, gives the number of lines of a message to be printed out
3920 with the top command;
3921 normally, the first five lines are printed.
3923 The character set of the terminal \*(UA operates on,
3924 and the one and only supported character set that \*(UA can use if no
3925 character set conversion capabilities have been compiled into it,
3926 in which case it defaults to `ISO-8859-1' unless it can deduce a value
3927 from the `LC_CTYPE' locale environment.
3928 Refer to the section
3929 .Sx "Character sets"
3930 for the complete picture about character sets.
3932 \*(IN Sets a global fallback user name, which is used in case none has
3933 been given in the protocol and account-specific URL and there is also
3936 This variable defaults to the value of
3941 for a specific host.
3943 Pathname of the text editor to use in the
3945 command and `~v' tilde escape.
3949 .\" .Sh ENVIRONMENT {{{
3951 Besides the variables described above,
3952 \*(UA uses the following environment variables:
3953 .Bl -tag -width ".It Va MAILRC"
3955 The user's preferred width in column positions for the terminal screen
3956 or window (only used during startup).
3958 The user's home directory.
3959 .It Va LANG , Va LC_ALL , Va LC_COLLATE , Va LC_CTYPE , Va LC_MESSAGES
3963 The user's preferred number of lines on a page or the vertical screen or
3964 window size in lines (only used during startup).
3966 Is used as a startup file instead of \*(ur if set.
3967 When \*(UA scripts are invoked on behalf of other users,
3968 this variable should be set to
3970 to avoid side-effects from reading their configuration files.
3972 If this variable is set and
3974 is not, it is treated as a startup configuration file and read.
3975 .It Va NAIL_NO_SYSTEM_RC
3976 If this variable is set then reading of \*(UR at startup is inhibited,
3977 i.e., the same effect is achieved as if \*(UA had been started up with
3981 Changes the letters printed in the first column of a header summary.
3983 \*(OP The terminal type for which output is to be prepared.
3985 Used as directory for temporary files instead of
3989 Can be used to force identification as
3991 i.e., identical to the
3993 command line option.
3999 .Bl -tag -width ".It Pa /etc/mime.types"
4001 File giving initial commands.
4003 System wide initialization file.
4004 .It Pa ~/.mime.types
4005 Personal MIME types.
4006 .It Pa /etc/mime.types
4007 System wide MIME types.
4011 .\" .Sh EXAMPLES {{{
4014 .\" .Ss "Getting started" {{{
4015 .Ss "Getting started"
4016 The \*(UA command has two distinct usages, according to whether one
4017 wants to send or receive mail.
4018 Sending mail is simple: to send a message to a user whose email address
4019 is, say, `<bill@host.example>', use the shell command:
4021 .Dl $ \*(ua bill@host.example
4023 then type your message.
4024 \*(UA will prompt you for a message `Subject:' first;
4025 after that, lines typed by you form the body of the message.
4026 When you reach the end of the message,
4027 type an EOT (`control\-D') at the beginning of a line,
4028 which will cause \*(UA to echo `EOT' and return you to the shell.
4030 If, while you are composing the message you decide that you do not wish
4031 to send it after all, you can abort the letter by typing two `RUBOUT'
4032 (interrupt, `control-C') characters.
4033 Typing a single `RUBOUT' causes \*(UA to print
4034 .Ns ` Ns Li (Interrupt -- one more to kill letter) Ns '.
4035 Typing a second `RUBOUT' causes \*(UA to save your partial letter on the
4038 and abort the letter.
4039 Once you have sent mail to someone, there is no way to undo the act, so
4042 If you want to send the same message to several other people,
4043 you can list their email addresses on the command line.
4044 .Bd -literal -offset indent
4045 $ \*(ua sam@workstation.example bob@server.example
4047 Tuition fees are due next Friday. Don't forget!
4053 will sendout to `<sam@workstation.example>' and `<bob@server.example>'.
4054 To read your mail, simply type
4058 \*(UA will respond by typing its version number and date and then
4059 listing the messages you have waiting.
4060 Then it will type a prompt and await your command.
4061 The messages are assigned numbers starting with 1 \(en you refer to the
4062 messages with these numbers.
4063 \*(UA keeps track of which messages are `new' (have been sent since you
4064 last read your mail) and `read' (have been read by you).
4065 New messages have an `N' next to them in the header listing and old,
4066 but unread messages have a `U' next to them.
4067 \*(UA keeps track of new/old and read/unread messages by putting a
4068 header field called `Status' into your messages.
4070 To look at a specific message, use the
4072 command, which may be abbreviated to simply `t'.
4073 For example, if you had the following messages:
4074 .Bd -literal -offset indent
4075 O 1 drfoo@myhost.example Wed Sep 1 19:52 5/421 "Fees"
4076 O 2 sam@friends.example Thu Sep 2 00:08 30/895
4079 you could examine the first message by giving the command:
4083 which might cause \*(UA to respond with, for example:
4084 .Bd -literal -offset indent
4085 [-- Message 1 -- 5 lines, 421 bytes --]:
4086 From drfoo@myhost.example Wed Sep 1 19:52:25 2004
4090 Tuition fees are due next Wednesday. Don't forget!
4093 Many \*(UA commands that operate on messages take a message number as an
4094 argument, just as the shown
4097 For these commands, there is a notion of a current message.
4098 When you enter the \*(UA program,
4099 the current message is initially the first (or the first recent) one.
4100 Thus, you can often omit the message number and use, for example, `t` to
4101 type the current message.
4102 As a further shorthand, you can type a message by simply giving its
4103 message number \(en hence `1` would type the first message.
4105 Frequently, it is useful to read the messages in your mailbox in order,
4107 You can read the next message in \*(UA by simply typing a newline.
4108 As a special case, you can type a newline as your first command to
4109 \*(UA to type the first message.
4111 If, after typing a message, you wish to immediately send a reply,
4112 you can do so with the command
4116 takes a message number as an argument.
4117 \*(UA then begins a message addressed to the user who sent you the
4118 message and let you type in your letter in reply, followed by
4119 a `<control-D>' at the beginning of a line, as before.
4121 Note that \*(UA copies the subject header from the original message.
4122 This is useful in that correspondence about a particular matter will
4123 tend to retain the same subject heading, making it easy to recognize.
4124 If there are other header fields in the message, like `Cc:',
4125 the information found will also be used.
4127 Sometimes you will receive a message that has been sent to several
4128 people and wish to reply only to the person who sent it.
4130 (with a capital `R') replies to a message, but sends a copy to the
4133 If you wish, while reading your mail, to send a message to someone,
4134 but not as a reply to one of your messages, you can send the message
4137 command, which takes as arguments the names of the recipients you wish
4139 For example, to send a message to `<frank@machine.example>':
4141 .Dl mail frank@machine.example
4143 To delete a message from the mail folder, you can use the command
4145 In addition to not saving deleted messages,
4146 \*(UA will not let you type them, either.
4147 The effect is to make the message disappear altogether, along with its
4150 Many features of \*(UA can be tailored to your liking with the
4152 command; it has two forms, depending on whether you are setting
4153 a `binary' or a `valued' option.
4154 Binary options are either on or off \(en for example, the
4156 option informs \*(UA that each time you send a message, you want it to
4157 prompt you for a `Cc:' header to be included in the message.
4160 option, you would type
4164 Valued options are values which \*(UA uses to adapt to your tastes.
4167 option tells \*(UA where to save messages sent by you,
4168 and is specified by, e.g.,
4172 Note that no spaces are allowed in `set record=Sent'.
4174 \*(UA includes a simple facility for maintaining groups of messages
4175 together in folders.
4176 To use the folder facility, you must tell \*(UA where you wish to keep
4178 Each folder of messages will be a single file.
4179 For convenience, all of your folders are kept in a single directory of
4181 To tell \*(UA where your folder directory is, put a line of the form
4183 .Dl set folder=letters
4186 If, as in the example above, your folder directory does not begin with
4187 a `/', \*(UA will assume that your folder directory is to be found
4188 starting from your home directory.
4190 Anywhere a file name is expected, you can use a folder name, preceded
4192 For example, to put a message into a folder with the
4194 command, you can use:
4198 to save the current message in the `classwork' folder.
4199 If the `classwork' folder does not yet exist, it will be created.
4200 Note that messages which are saved with the
4202 command are automatically removed from your system mailbox.
4204 In order to make a copy of a message in a folder without causing
4205 that message to be removed from your system mailbox, use the
4207 command, which is identical in all other respects to the
4214 can be used to direct \*(UA to the contents of a different folder.
4217 .Dl folder +classwork
4219 directs \*(UA to read the contents of the `classwork' folder.
4220 All of the commands that you can use on your system mailbox are also
4221 applicable to folders, including
4226 To inquire which folder you are currently editing, use `folder' without
4228 And to list your current set of folders, use the
4234 command is available to print out a brief summary of the most important
4237 While typing in a message to be sent to others it is often useful to be
4238 able to invoke the text editor on the partial message, print the
4239 message, execute a shell command, or do some other auxiliary function.
4240 \*(UA provides these capabilities through `tilde escapes',
4241 which consist of a tilde (`~') at the beginning of a line, followed by
4242 a single character which indicates the function to be performed.
4243 For example, to print the text of the message so far, use:
4247 which will print a line of dashes, the recipients of your message, and
4248 the text of the message so far.
4249 A list of the most important tilde escapes is available with `~?'.
4252 .\" .Ss "IMAP or POP3 client setup" {{{
4253 .Ss "IMAP or POP3 client setup"
4254 \*(OP First you need the following data from your ISP:
4255 the host name of the IMAP or POP3 server,
4256 user name and password for this server,
4257 and a notice whether the server uses SSL/TLS encryption.
4258 Assuming the SSL/TLS secured host name of your IMAP account is
4259 `server.myisp.example' and your user name for that server is `mylogin',
4260 you could refer to this account using the
4264 command line option with
4266 .Dl imaps://mylogin@server.myisp.example
4268 (This string is not necessarily the same as your Internet mail address.)
4269 Even if the server does not accept IMAPS or POP3S connections,
4270 it is possible that it supports the `STARTTLS' method of upgrading
4271 already connected, but not yet authenticated sessions to use SSL/TLS
4273 The only reliable method to see if this works is to try it; enter one of
4275 .Dl set imap-use-starttls
4276 .Dl set pop3-use-starttls
4278 before you initiate the connection, dependent on the actual protocol.
4280 As you probably want messages to be deleted from this account
4281 after saving them, prefix it with `%:'.
4284 command can be used to avoid typing that many characters every time you
4287 .Dl shortcut myisp %:imaps://mylogin@server.myisp.example
4289 You might want to put this string into a startup file.
4291 is one of those commands that are specific to \*(UA and will thus
4292 confuse other implementations of POSIX
4294 so it should possibly not be placed in \*(ur.
4297 .Dl set NAIL_EXTRA_RC=.\*(uarc
4299 in \*(ur and create a file
4301 containing all the commands that are specific to \*(UA.
4302 You can then access your remote mailbox by invoking
4306 on the command line, or by executing
4311 If you want to use more than one IMAP mailbox on a server,
4312 or if you want to use the IMAP server for mail storage too, the
4314 command (which is also \*(UA-specific) is possibly more appropriate.
4315 You can put the following in
4317 .Bd -literal -offset indent
4319 set folder=imaps://mylogin@server.myisp.example
4320 set record=+Sent MBOX=+mbox outfolder
4324 and can then access incoming mail for this account by invoking
4325 `\*(ua \-A myisp' on the command line or by executing `ac myisp' within
4327 After that, a command like `copy 1 +otherfolder' will refer to
4328 `otherfolder' on the IMAP server.
4329 In particular, `fi&' will change to the `mbox' folder,
4330 and `fi+Sent' will show your recorded sent mail,
4331 with both folders located on the IMAP server.
4333 \*(UA will ask you for a password string each time you connect to
4335 If you can reasonably trust the security of your workstation,
4336 you can give this password in the startup file as
4338 .Dl set password-mylogin@server.myisp.example="SECRET"
4340 You should change the permissions of this file to 0600, see
4343 \*(UA supports different authentication methods for both IMAP and POP3.
4344 If Kerberos is used at your location,
4345 you can try to activate (the optional) GSS-API based authentication via
4347 .Dl set imap-auth=gssapi
4349 The advantage of this method is that \*(UA doesn't need to know your
4350 password at all, nor does it have to send sensitive data over the network.
4351 If that isn't possible, try to use authentication methods that at least
4352 avoid sending the password in clear over the wire, which is especially
4353 important if SSL/TLS cannot be used, e.g.,
4355 .Dl set imap-auth=cram-md5
4357 For POP3 \*(UA will try to use the `APOP' mechanism automatically unless
4358 explicitly disabled.
4359 If the server does not offer any such authentication methods,
4360 conventional user/password based authentication must be used.
4361 It is sometimes helpful, especially when setting up an account or when
4362 there are authentification problems, to enable verbosity by setting the
4364 option \(en \*(UA will display all data sent to the server in clear text
4365 on the screen when this option is set.
4366 (Because this may also include passwords you should take care that no
4367 unauthorized person can look at your terminal when this option is set.)
4369 If you regularly use the same workstation to access IMAP accounts,
4370 you can greatly enhance performance by enabling local caching of IMAP
4372 For any message that has been fully or partially fetched from the server,
4373 a local copy is made and is used when the message is accessed again,
4374 so most data is transferred over the network once only.
4375 To enable the IMAP cache, select a local directory name and put
4377 .Dl set imap-cache=~/localdirectory
4379 in the (\*(UA-specific) startup file.
4380 All files within that directory can be overwritten or deleted by \*(UA
4382 so you should not use the directory to store other information.
4384 Once the cache contains some messages,
4385 it is not strictly necessary anymore to open a connection to the IMAP
4386 server to access them.
4387 When \*(UA is invoked with the option
4392 only cached data is used for any folder you open.
4393 Messages that have not yet been completely cached are not available
4394 then, but all other messages can be handled as usual.
4395 Changes made to IMAP mailboxes in
4397 mode are committed to the IMAP server next time it is used in
4400 Synchronizing the local status with the status on the server is thus
4401 partially within your responsibility;
4402 if you forget to initiate a connection to the server again before you
4403 leave your location,
4404 changes made on one workstation are not available on others.
4405 Also if you alter IMAP mailboxes from a workstation while uncommitted
4406 changes are still pending on another,
4407 the latter data may become invalid.
4408 The same might also happen because of internal server status changes.
4409 You should thus carefully evaluate this feature in your environment
4410 before you rely on it.
4412 Many servers will close the connection after a short period of
4413 inactivity \(en use one of
4415 .Dl set pop3-keepalive=30
4416 .Dl set imap-keepalive=240
4418 to send a keepalive message each 30 seconds for POP3,
4419 or each 4 minutes for IMAP.
4421 If you encounter problems connecting to a SSL/TLS server,
4426 variables (see the OpenSSL FAQ for more information) or specify the
4427 protocol version with
4429 Contact your ISP if you need a client certificate or if verification of
4430 the server certificate fails.
4431 If the failed certificate is indeed valid,
4432 fetch its CA certificate by executing the shell command
4434 .Dl $ </dev/null openssl s_client \-showcerts \-connect \e
4435 .Dl \ \ \ \ \ \ server.myisp.example:imaps 2>&1 | tee log.txt
4439 ) and put it into the file specified with
4441 The data you need is located at the end of the certificate chain
4442 within (and including) the `BEGIN CERTIFICATE'
4443 and `END CERTIFICATE' lines.
4444 Note that the example above is \fBinsecure\fR!
4445 One should use the `-verify' and `-CAfile' options of
4447 to be "on the safe side" regarding the fetched certificates.
4450 .\" .Ss "Reading HTML mail" {{{
4451 .Ss "Reading HTML mail"
4456 utility or another command-line web browser that can write plain text to
4459 .Dl set pipe-text/html="elinks -force-html -dump 1"
4460 .Dl set pipe-text/html="lynx -stdin -dump -force_html"
4462 will cause HTML message parts to be converted into a more friendly form.
4465 .\" .Ss "Viewing PDF attachments" {{{
4466 .Ss "Viewing PDF attachments"
4467 Most PDF viewers do not accept input directly from a pipe.
4468 It is thus necessary to store the attachment in a temporary file first:
4470 .Dl set pipe-application/pdf="@&cat >/tmp/\*(ua$$.pdf; \e
4471 .Dl \ \ \ \ \ \ acroread /tmp/\*(ua$$.pdf; rm /tmp/\*(ua$$.pdf"
4473 Note that security defects are discovered in PDF viewers from time to
4475 Automatical command execution like this can compromise your system
4477 in particular if you stay not always informed about such issues.
4480 .\" .Ss "Signed and encrypted messages with S/MIME" {{{
4481 .Ss "Signed and encrypted messages with S/MIME"
4482 \*(OP S/MIME provides two central mechanisms:
4483 message signing and message encryption.
4484 A signed message contains some data in addition to the regular text.
4485 The data can be used to verify that the message was sent using a valid
4486 certificate, that the sender's address in the message header matches
4487 that in the certificate, and that the message text has not been altered.
4488 Signing a message does not change its regular text;
4489 it can be read regardless of whether the recipient's software is able to
4491 It is thus usually possible to sign all outgoing messages if so desired.
4492 Encryption, in contrast, makes the message text invisible for all people
4493 except those who have access to the secret decryption key.
4494 To encrypt a message, the specific recipient's public encryption key
4496 It is thus not possible to send encrypted mail to people unless their
4497 key has been retrieved from either previous communication or public key
4499 A message should always be signed before it is encrypted.
4500 Otherwise, it is still possible that the encrypted message text is
4503 A central concept to S/MIME is that of the certification authority (CA).
4504 A CA is a trusted institution that issues certificates.
4505 For each of these certificates it can be verified that it really
4506 originates from the CA, provided that the CA's own certificate is
4508 A set of CA certificates is usually delivered with OpenSSL and installed
4510 If you trust the source of your OpenSSL software installation,
4511 this offers reasonable security for S/MIME on the Internet.
4512 In general, a certificate cannot be more secure than the method its CA
4513 certificate has been retrieved with, though.
4514 Thus if you download a CA certificate from the Internet,
4515 you can only trust the messages you verify using that certificate as
4516 much as you trust the download process.
4518 The first thing you need for participating in S/MIME message exchange is
4519 your personal certificate, including a private key.
4520 The certificate contains public information, in particular your name and
4521 your email address, and the public key that is used by others to encrypt
4523 and to verify signed messages they supposedly received from you.
4524 The certificate is included in each signed message you send.
4525 The private key must be kept secret.
4526 It is used to decrypt messages that were previously encrypted with your
4527 public key, and to sign messages.
4529 For personal use it is recommended that you get a S/MIME certificate
4530 from one of the major CAs on the Internet using your WWW browser.
4531 (Many CAs offer such certificates for free.)
4532 You will usually receive a combined certificate and private key in
4533 PKCS#12 format which \*(UA does not directly accept.
4534 To convert it to PEM format, use the following shell command:
4536 .Dl $ openssl pkcs12 \-in cert.p12 \-out cert.pem \-clcerts \-nodes
4538 If you omit the `\-nodes' parameter, you can specifiy an additional `PEM
4539 pass phrase' for protecting the private key.
4540 \*(UA will then ask you for that pass phrase each time it signs or
4544 .Dl set smime-sign-cert-myname@myisp.example=cert.pem
4546 to make this private key and certificate known to \*(UA.
4547 You can now sign outgoing messages.
4553 From each signed message you send,
4554 the recipient can fetch your certificate and use it to send encrypted
4556 Accordingly if somebody sends you a signed message, you can do the same.
4559 command to check the validity of the certificate.
4560 After that, retrieve the certificate and tell \*(UA that it should use
4563 .Dl certsave filename
4564 .Dl set smime-encrypt-USER@HOST=filename
4566 You should carefully consider if you prefer to store encrypted messages
4568 If you do, anybody who has access to your mail folders can read them,
4569 but if you do not, you might be unable to read them yourself later if
4570 you happen to lose your private key.
4573 command saves messages in decrypted form, while the
4578 commands leave them encrypted.
4580 Note that neither S/MIME signing nor encryption applies to message
4581 subjects or other header fields.
4582 Thus they may not contain sensitive information for encrypted messages,
4583 and cannot be trusted even if the message content has been verified.
4584 When sending signed messages,
4585 it is recommended to repeat any important header information in the
4589 .\" .Ss "Using CRLs with S/MIME or SSL/TLS" {{{
4590 .Ss "Using CRLs with S/MIME or SSL/TLS"
4591 \*(OP Certification authorities (CAs) issue certificate revocation
4592 lists (CRLs) on a regular basis.
4593 These lists contain the serial numbers of certificates that have been
4594 declared invalid after they have been issued.
4595 Such usually happens because the private key for the certificate has
4597 because the owner of the certificate has left the organization that is
4598 mentioned in the certificate, etc.
4599 To seriously use S/MIME or SSL/TLS verification,
4600 an up-to-date CRL is required for each trusted CA.
4601 There is otherwise no method to distinguish between valid and
4602 invalidated certificates.
4603 \*(UA currently offers no mechanism to fetch CRLs, nor to access them on
4604 the Internet, so you have to retrieve them by some external mechanism.
4606 \*(UA accepts CRLs in PEM format only;
4607 CRLs in DER format must be converted, like, e.\|g.:
4609 .Dl $ openssl crl \-inform DER \-in crl.der \-out crl.pem
4611 To tell \*(UA about the CRLs, a directory that contains all CRL files
4612 (and no other files) must be created.
4617 variables, respectively, must then be set to point to that directory.
4618 After that, \*(UA requires a CRL to be present for each CA that is used
4619 to verify a certificate.
4622 .\" .Ss "Handling spam" {{{
4624 \*(OP \*(UA can make use of spam detection and learning facilities \(en
4625 more precisely, SpamAssassin (\%<http://spamassassin.apache.org>).
4626 A very comprehensive documentation of
4628 can be found at the O'Reilly Commons
4629 (\%<http://commons.oreilly.com/wiki/index.php/SpamAssassin>).
4631 Currently \*(UA supports interaction with
4633 only via its daemonized
4636 server / client pair, which means that, in order to detect and work
4637 with spam through \*(UA, an instance of the
4639 daemon must be running (the examples are equivalent):
4640 .Bd -literal -offset indent
4641 $ spamd -i localhost:2142 -i /tmp/.spamsock -d [-L] [-l]
4642 $ spamd --listen=localhost:2142 --listen=/tmp/.spamsock \\
4643 --daemonize [--local] [--allow-tell]
4648 should only listen on a local, path-based UNIX domain socket instead of
4649 offering its service over the network, it maybe necessary to use
4652 option instead of the shown
4654 In order to support training of the Bayesian classifier through \*(UA,
4656 must have been started with the
4662 is running \*(UA can classify messages by using the client side program,
4665 .Bd -literal -offset indent
4666 $ \*(ua -Sspam-command=/usr/local/bin/spamc \\
4667 -Sspam-socket=/tmp/.spamsock -Sspam-maxsize=500000
4670 The commands offered are
4674 which simply set an `is-spam' flag that can be used for, e.g., message
4677 which passes messages through to the spam detector in order to gain
4678 a spam score and conditionally set the `is-spam' flag accordingly,
4679 as well as the Bayesian filter related
4685 Because messages must exist on local storage in order to be scored (or
4686 used for Bayesian filter training), it is possibly a good idea to
4687 perform the local spam check last:
4688 .Bd -literal -offset indent
4689 define spamdelhook {
4691 spamset (header x-dcc-brand-metrics "bulk")
4692 # Server-side spamassassin(1)
4693 spamset (header x-spam-flag "YES")
4694 del :s # TODO we HAVE to be able to do `spamrate :u ! :s'
4695 # And finally the local spamc(1)
4699 set folder-hook-FOLDER=spamdelhook
4702 See also the documentation for the variables
4712 .\" .Ss "Sending mail from scripts" {{{
4713 .Ss "Sending mail from scripts"
4714 If you want to send mail from scripts, you must be aware that \*(UA
4715 reads the user's configuration files by default.
4716 So unless your script is only intended for your own personal use
4717 (as, e.g., a cron job), you need to circumvent this:
4719 .Dl MAILRC=/dev/null \*(ua \-n
4721 You then need to create a script-local configuration for \*(UA.
4722 This can be done by either pointing the
4724 variable to a custom configuration file,
4725 by passing the configuration in environment variables,
4728 command line option to specify options.
4729 Since many configuration options are not valid shell variables, the
4731 command is useful if the approach via environment variables is used:
4732 .Bd -literal -offset indent
4733 env MAILRC=/dev/null password=secret \*(ua -n -Sv15-compat \e
4734 -S 'smtp=smtps://mylogin@some.host:465' -Ssmtp-auth=login \e
4735 -S 'from=scriptreply@domain' \e
4736 -s 'subject' -a attachment_file recipient@domain < content_file
4741 .\" .Sh "SEE ALSO" {{{
4754 .Xr spamassassin 1 ,
4772 .\" .Sh "IMPLEMENTATION NOTES" {{{
4773 .Sh "IMPLEMENTATION NOTES"
4774 The character set conversion uses and relies upon the
4777 Its functionality differs widely between the various system environments
4780 Limitations with IMAP mailboxes are:
4781 It is not possible to edit messages, but it is possible to append them.
4782 Thus to edit a message, create a local copy of it, edit it, append it,
4783 and delete the original.
4784 The line count for the header display is only appropriate if the entire
4785 message has been downloaded from the server.
4786 The marking of messages as `new' is performed by the IMAP server;
4791 will not cause it to be reset, and if the
4793 variable is unset, messages that arrived during a session will not be
4794 in state `new' anymore when the folder is opened again.
4795 Also if commands queued in disconnected mode are committed,
4796 the IMAP server will delete the `new' flag for all messages in the
4798 and new messages will appear as unread when it is selected for viewing
4800 The `flagged', `answered', and `draft' attributes are usually permanent,
4801 but some IMAP servers are known to drop them without notification.
4802 Message numbers may change with IMAP every time before the prompt is
4803 printed if \*(UA is notified by the server that messages have been
4804 deleted by some other client or process.
4805 In this case, `Expunged n messages' is printed, and message numbers may
4808 Limitations with POP3 mailboxes are:
4809 It is not possible to edit messages, they can only be copied and deleted.
4810 The line count for the header display is only appropriate if the entire
4811 message has been downloaded from the server.
4812 The status field of a message is maintained by the server between
4813 connections; some servers do not update it at all, and with a server
4814 that does, the `exit' command will not cause the message status to be
4816 The `newmail' command and the `newmail' variable have no effect.
4817 It is not possible to rename or to remove POP3 mailboxes.
4819 If a `RUBOUT' (interrupt, `control-C') is typed while an IMAP or POP3
4820 operation is in progress, \*(UA will wait until the operation can be
4822 and will then return to the command loop and print the prompt again.
4823 When a second `RUBOUT' is typed while \*(UA is waiting for the operation
4824 to complete, the operation itself will be cancelled.
4825 In this case, data that has not been fetched yet will have to be fetched
4826 before the next command can be performed.
4827 If the cancelled operation was using an SSL/TLS encrypted channel,
4828 an error in the SSL transport will very likely result and render the
4829 connection unusable.
4831 As \*(UA is a mail user agent, it provides only basic SMTP services.
4832 If it fails to contact its upstream SMTP server, it will not make
4833 further attempts to transfer the message at a later time,
4834 and it does not leave other information about this condition than an
4835 error message on the terminal and an entry in
4837 This is usually not a problem if the SMTP server is located in the same
4838 local network as the computer on which \*(UA is run.
4839 However, care should be taken when using a remote server of an ISP;
4840 it might be better to set up a local SMTP server then which just acts as
4843 \*(UA immediately contacts the SMTP server (or
4845 ) even when operating in
4848 It would not make much sense for \*(UA to defer outgoing mail since SMTP
4849 servers usually provide much more elaborated delay handling than \*(UA
4850 could perform as a client.
4851 Thus the recommended setup for sending mail in
4853 mode is to configure a local SMTP server such that it sends outgoing
4854 mail as soon as an external network connection is available again,
4855 i.e., to advise it to do that from a network startup script.
4860 A \fImail\fR command appeared in Version 1 AT&T Unix.
4861 Berkeley Mail was written in 1978 by Kurt Shoens.
4862 This man page is derived from from The Mail Reference Manual originally
4863 written by Kurt Shoens.
4864 "Heirloom Mailx" enhancements are maintained and documented by Gunnar
4866 "S-nail" is maintained and documented by Steffen (Daode) Nurpmeso.
4868 Portions of this text are reprinted and reproduced in electronic form
4869 from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
4870 \(en Operating System Interface (POSIX), The Open Group Base
4871 Specifications Issue 6, Copyright \(co 2001-2003 by the Institute of
4872 Electrical and Electronics Engineers, Inc and The Open Group.
4873 In the event of any discrepancy between this version and the original
4874 IEEE and The Open Group Standard, the original IEEE and The Open Group
4875 Standard is the referee document.
4876 The original Standard can be obtained online at
4877 \%<http://www.opengroup.org/unix/online.html>.
4878 Redistribution of this material is permitted so long as this notice
4884 .An "Christos Zoulas" ,
4885 .An "Gunnar Ritter" ,
4886 .An Steffen Po Daode Pc Nurpmeso Aq s-nail-users@lists.sourceforge.net
4889 Too many (see the file `TODO' from the distribution or the repository).