1 .\"@ nail.1 - S-nail(1) reference manual.
3 .\" Copyright (c) 1980, 1990, 1993
4 .\" The Regents of the University of California. All rights reserved.
6 .\" Gunnar Ritter. All rights reserved.
7 .\" Copyright (c) 2012 - 2015 Steffen (Daode) Nurpmeso <sdaoden@users.sf.net>.
9 .\" Redistribution and use in source and binary forms, with or without
10 .\" modification, are permitted provided that the following conditions
12 .\" 1. Redistributions of source code must retain the above copyright
13 .\" notice, this list of conditions and the following disclaimer.
14 .\" 2. Redistributions in binary form must reproduce the above copyright
15 .\" notice, this list of conditions and the following disclaimer in the
16 .\" documentation and/or other materials provided with the distribution.
17 .\" 3. All advertising materials mentioning features or use of this software
18 .\" must display the following acknowledgement:
19 .\" This product includes software developed by the University of
20 .\" California, Berkeley and its contributors.
21 .\" This product includes software developed by Gunnar Ritter
22 .\" and his contributors.
24 .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS 'AS IS' AND
25 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 .\" S-nail(1): v14.8.10 / 2016-08-20
49 .\" If not ~/.mailrc, it breaks POSIX compatibility. And adjust main.c.
54 .ds OU [no v15-compat]
55 .ds ID [v15 behaviour may differ]
66 .Nd send and receive Internet mail
79 .Op Fl a Ar attachment
82 .Op Fl q Ar quote-file
84 .Op Fl S Ar variable Ns Op Ns = Ns Ar value
89 .Op Fl Fl \~ Ns Ar mta-option ...
98 .Op Fl S Ar variable Ns Op Ns = Ns Ar value
101 .Op Fl Fl \~ Ns Ar mta-option ...
108 .Op Fl L Ar spec-list
109 .Op Fl r Ar from-addr
110 .Op Fl S Ar variable Ns Op Ns = Ns Ar value
113 .Op Fl Fl \~ Ns Ar mta-option ...
118 .Mx -toc -tree html pdf ps xhtml
121 .\" .Sh DESCRIPTION {{{
124 .Bd -filled -compact -offset indent
125 .Sy Compatibility note:
126 S-nail (\*(UA) will wrap up into \%S-mailx in v15.0 (circa 2018).
127 A partial set of compatibility options exist, tagged as \*(IN and \*(OU.
128 To choose upward compatible behaviour, please set the internal variable
130 Anything which will vanish in v15.0 is tagged \*(OB, and using
132 will print warnings for many use cases of obsolete features.
136 \*(UA is a mail processing system with a command syntax reminiscent of
138 with lines replaced by messages.
139 It is intended to provide the functionality of the POSIX
141 command, but is MIME capable and optionally offers extensions for
142 line editing, S/MIME, SMTP and POP3 among others.
143 It is usable as a mail batch language.
145 .\" .Ss "Options" {{{
148 .Bl -tag -width ".Fl _ Ar _ccount"
151 Explicitly control which of the
153 shall be loaded: if the letter
155 is (case-insensitively) part of the
159 is loaded, likewise the letter
161 controls loading of the user's personal
163 file, whereas the letters
167 explicitly forbid loading of any resource files.
168 This option should be used by scripts: to avoid environmental noise they
171 from any configuration files and create a script-local environment,
172 explicitly setting any desired variable via
174 This option overrides
181 command (see below) for
183 after the startup files have been read.
187 Attach the given file to the message.
188 The same filename conventions as described in the section
190 apply: shell word expansion is restricted to the tilde
195 not be accessible but contain a
197 character, then anything after the
199 is assumed to specify the input character set and anything before
201 the filename: this is the only option to specify the input character set
202 (and don't perform any character set conversion) for text attachments
203 from the command line, not using the
205 tilde escape command.
209 Make standard input and standard output line-buffered.
213 Send a blind carbon copy to
215 Can be used multiple times, but it is also possible to give
216 a comma-separated list of receivers in a single argument, proper shell
217 quoting provided, e.g.,
218 .Ql -b """qrec1 , rec2,rec3, Ex <am@ple>""" .
220 .Sx "On sending mail, and non-interactive mode" .
224 Send carbon copies to the given receiver(s).
225 Can be used multiple times.
231 variable which enables debug messages and disables message delivery,
232 among others; effectively turns almost any operation into a dry-run.
238 variable and thus discard messages with an empty message part body.
239 This is useful for sending messages from scripts.
243 Just check if mail is present (in the specified or system mailbox).
244 If yes, return an exit status of zero, a non-zero value otherwise.
245 To restrict the set of mails to consider in this evaluation a message
246 specification can be added with the option
251 Save the message to send in a file named after the local part of the
252 first recipient's address (instead of in
257 Read in the contents of the user's
259 (or the specified file) for processing;
260 when \*(UA is quit, it writes undeleted messages back to this file
264 Some special conventions are recognized for the string
266 which are documented for the
271 is not a direct argument to the flag
273 but is instead taken from the command line after option processing has
277 that starts with a hyphen, prefix it with a (relative) path, as in
278 .Ql ./-hyphenbox.mbox .
282 Display a summary of the
284 of all messages in the specified or system mailbox and exit.
285 A configurable summary view is available via the
291 Show a short usage summary.
292 Because of widespread use a
294 argument will have the same effect.
300 variable to ignore tty interrupt signals.
303 .It Fl L Ar spec-list
304 Display a summary of all
306 of only those messages in the specified or system mailbox that match the
311 .Sx "Specifying messages"
318 option has been given in addition no header summary is produced,
319 but \*(UA will instead indicate via its exit status wether
325 note that any verbose output is suppressed in this mode and must instead
326 be enabled explicitly (e.g., by using the option
333 variable and thus inhibit initial display of message headers when
334 reading mail or editing a mail folder.
338 Standard flag that inhibits reading the system wide
343 allows more control over the startup sequence; also see
344 .Sx "Resource files" .
348 Initialize the message body with the contents of the specified file,
349 which may be standard input
351 only in non-interactive context.
352 May be given in send mode only.
356 Any folder opened will be in read-only mode.
362 is a valid address then it specifies the envelope sender address to be
365 when a message is send.
368 include a user name, comments etc., then the components will be
369 separated and the name part will be passed to the MTA individually via
373 will also be assigned to the
375 variable, just as if additionally
377 had been specified (therefore affecting SMTP data transfer, too).
379 If instead an empty string is passed as
381 then the content of the variable
383 will be evaluated and used for this purpose whenever the MTA is
385 Note that \*(UA by default, without
387 that is, neither passes
391 flags to the MTA by itself.
394 .It Fl S Ar variable Ns Op = Ns value
395 Sets the internal option
397 and, in case of a value option, assigns
400 Even though variables set via
402 may be overwritten from within resource files,
403 the command line setting will be reestablished after all resource files
408 Specify the subject of the to-be-sent message.
412 The message given (on standard input) is expected to contain, separated
413 from the message body with an empty line, a message header with
418 fields giving its recipients, which will be added to those given on the
420 If a message subject is specified via
422 then it'll be used in favour of one given on the command line.
431 Note you can also specify
435 and the envelope address possibly specified with the option
438 The following, which are normally created automatically based
439 upon the message context, can also be specified:
444 .Ql Mail-Followup-To:
445 (special address massage will however still occur for the latter).
446 In fact custom header fields may also be used, the content of which
447 is passed through unchanged.
451 can be embedded, too.
455 Read the system mailbox of
457 (appropriate privileges presumed), and
460 in some aspects, e.g. in respect to
469 Show \*(UA's version and exit.
475 option enables display of some informational context messages.
476 Using it twice increases the level of verbosity.
482 to the list of commands to be executed before normal operation starts.
486 .Va batch-exit-on-error ;
487 the only possibility to execute commands in non-interactive mode when
488 reading startup files is actively prohibited.
494 even if not in interactive mode.
499 In batch mode the full set of commands is available, just like in
500 interactive mode, and diverse variable settings and internal states are
501 adjusted for batch necessities, e.g., it sets
512 It also enables processing of
513 .Sx "TILDE ESCAPES" .
514 E.g., the following should send an email message to
516 .Bd -literal -offset indent
517 $ LC_ALL=C printf 'm bob\en~s ubject\enText\en~.\enx\en' | \e
518 LC_ALL=C \*(ua -:/ -d#
523 This flag forces termination of option processing in order to prevent
526 It also forcefully puts \*(UA into send mode, see
527 .Sx "On sending mail, and non-interactive mode" .
531 In the above list of supported command line options,
535 are implemented by means of setting the respective option, as via
538 .Op Ar mta-option ...
540 arguments that are given at the end of the command line after a
542 separator will be passed through to the mail-transfer-agent (MTA) and
543 persist for an entire (interactive) session \(en if the setting of
545 allows their recognition;
546 MTA arguments can also be specified in the variable
547 .Va sendmail-arguments ;
548 find MTA interaction described in more detail in the documentation of
550 MTA arguments are ignored when mail is send via SMTP data transfer.
553 .\" .Ss "A starter" {{{
556 \*(UA is a direct descendant of
558 Mail, a successor of the Research
561 .Dq was there from the start
566 Mail reference manual begins with the following words:
568 .Bd -ragged -offset indent
569 Mail provides a simple and friendly environment for sending and
571 It divides incoming mail into its constituent messages and allows the
572 user to deal with them in any order.
573 In addition, it provides a set of
575 -like commands for manipulating messages and sending mail.
576 Mail offers the user simple editing capabilities to ease the composition
577 of outgoing messages, as well as providing the ability to define and
578 send to names which address groups of users.
582 \*(UA is thus the user side of the
584 mail system, whereas the system side (mail-transfer-agent, MTA) was
585 traditionally taken by
591 are often used for this purpose instead.
592 If the \*(OPal SMTP is included in the
594 of \*(UA then the system side is not a mandatory precondition for mail
598 Because \*(UA strives for compliance with POSIX
600 it is likely that some configuration settings have to be adjusted before
601 using it is a smooth experience.
604 file already bends those standard settings a bit towards more user
605 friendliness and safety, e.g., it sets the
609 variables in order to suppress the automatic moving of messages to
611 that would otherwise occur (see
612 .Sx "Message states" )
615 to not remove empty files in order not to mangle file permissions when
616 files eventually get recreated.
619 option so that by default file grouping (via the
621 prefix as documented also for
626 contains some further suggestions.
629 .\" .Ss "On sending mail, and non-interactive mode" {{{
630 .Ss "On sending mail, and non-interactive mode"
632 To send a message to one or more people, using a local
633 mail-transfer-agent (MTA; the executable path can be set via
635 or the \*(OPal builtin SMTP (set and see the variable
637 transport to actually deliver the generated mail message, \*(UA can be
638 invoked with arguments which are the names of people to whom the mail
641 .Bd -literal -offset indent
642 $ \*(ua -s Subject -a attachm.ent bill@host1 'Bob <bob@host2>'
643 # But... try it in an isolated dry-run mode first
644 $ LC_ALL=C \*(ua -:/ -d -vv -Sfrom="me <he@exam.ple>" \e
645 -b bcc@exam.ple -c cc@exam.ple \e
646 -s Subject -. "(Lovely) Bob <bob@host2>"
650 The command line options
654 can be used to add (blind) carbon copy receivers.
655 Almost always lists of addresses can be given where an address is
657 whereas comma-separated lists should be given, e.g.,
658 .Ql -c """r1@exam.ple , r2@exam.ple,r3@exam.ple""" ,
659 that very example could also be given as the whitespace-separated list
660 .Ql -c """r1@exam.ple r2@exam.ple r3@exam.ple""" ,
661 but which for obvious reasons would not work for
662 .Ql -c """R1 <r1@exam.ple>, R2 (heh!) <r2@exam.ple>""" .
665 The user is then expected to type in the message contents.
666 In this compose mode \*(UA treats lines beginning with the character
668 special \(en these are so-called
670 which can be used to read in files, process shell commands, add and edit
671 attachments and more; e.g., the tilde escape
673 will start the text editor to revise the message in it's current state,
675 allows editing of the message recipients and
677 gives an overview of available tilde escapes.
680 at the beginning of an empty line leaves compose mode and causes the
681 message to be sent, whereas typing
684 twice will abort the current letter (saving its contents in the file
692 A number of variables can be used to alter default behavior; e.g.,
697 will automatically startup a text editor when compose mode is entered,
699 will cause the user to be prompted actively for carbon-copy recipients
702 option will allow leaving compose mode by writing a line consisting
707 Very important, though, is to define which
709 may be used when sending messages, usually by setting the option
712 having read the section
713 .Sx "The mime.types files"
714 to understand how the MIME-type of outgoing attachments is classified
715 and the knowledge that messages are sent asynchronously unless
717 is set: only with it MTA delivery errors will be recognizable.
722 is often necessary (e.g., in conjunction with
724 or desirable, you may want to do some dry-run tests before you go.
725 Saving a copy of the sent messages in a
727 may also be desirable \(en as for most mailbox file targets some
728 special conventions are recognized, see the
730 command for more on that.
732 .Sx "On URL syntax and credential lookup"
733 will spread some light on the
735 variable chains as well as on using URLs for accessing protocol-specific
740 contains an example configuration for sending messages via some of the
741 well-known public mail providers;
742 note it also gives a compact overview on how to setup a secure SSL/TLS
746 Message recipients (as specified on the command line or defined in
751 may not only be email addressees but can also be names of mailboxes and
752 even complete shell command pipe specifications.
753 Proper (shell) quoting is necessary, e.g., to embed whitespace characters.
754 (Recall that \*(UA deals with mail standards, therefore those define the
755 rules with which content is interpreted.)
758 is not set then only network addresses (see
760 for a description of mail addresses) and plain user names (including MTA
761 aliases) may be used, other types will be filtered out, giving a warning
764 .\" When changing any of the following adjust any RECIPIENTADDRSPEC;
765 .\" grep the latter for the complete picture
769 is set then extended recipient addresses will optionally be accepted:
770 Any name which starts with a vertical bar
772 character specifies a command pipe \(en the command string following the
774 is executed and the message is sent to its standard input;
775 Likewise, any name that starts with the character slash
777 or the character sequence dot slash
779 is treated as a file, regardless of the remaining content.
780 Any other name which contains an at sign
782 character is treated as a network address;
783 Any other name which starts with a plus sign
785 character specifies a mailbox name;
786 Any other name which contains a slash
788 character but no exclamation mark
792 character before also specifies a mailbox name;
793 What remains is treated as a network address.
795 .Bd -literal -offset indent
796 $ echo bla | \*(ua -Sexpandaddr -s test ./mbox.mbox
797 $ echo bla | \*(ua -Sexpandaddr -s test '|cat >> ./mbox.mbox'
798 $ echo safe | LC_ALL=C \e
799 \*(ua -:/ -Sv15-compat -Ssendwait -Snosave \e
800 -Sexpandaddr=fail,-all,+addr -s test \e
805 It is possible to create personal distribution lists via the
807 command, so that, for instance, the user can send mail to
809 and have it go to a group of people:
812 .Dl alias cohorts bill jkf mark kridle@ucbcory ~/mail/cohorts.mbox
815 Please note that this mechanism has nothing in common with the system
816 wide aliases that may be used by the local MTA (mail-transfer-agent),
817 which are subject to the
821 and are often tracked in a file
827 Personal aliases will be expanded by \*(UA before the message is sent,
828 and are thus a convenient alternative to specifying each addressee by
832 To avoid environmental noise scripts should
834 \*(UA from any configuration files and create a script-local
835 environment, ideally with the command line options
837 to disable any configuration file in conjunction with repititions of
839 to specify variables:
841 .Bd -literal -offset indent
842 $ env LC_ALL=C password=NOTSECRET \e
843 \*(ua -:/ -Sv15-compat -Ssendwait -Snosave \e
844 -Sexpandaddr=fail,-all,+addr \e
845 -S 'smtp=smtps://mylogin@some.host:465' -Ssmtp-auth=login \e
846 -S 'from=scriptreply@domain' \e
847 -s 'subject' -a attachment_file \e
848 -. "Recipient 1 <recipient1@domain>" recipient2@domain \e
853 In interactive mode, which is introduced in the next section, messages
854 can be sent by calling the
856 command with a list of recipient addresses \(em the semantics are
857 completely identical to non-interactive message sending, except that
858 it is likely necessary to separate recipient lists with commas:
860 .Bd -literal -offset indent
861 $ \*(ua -d -Squiet -Semptystart
862 "/var/spool/mail/user": 0 messages
863 ? mail "Recipient 1 <recipient1@domain>", recipient2@domain
864 ? # Will do the right thing (tm)
865 ? m recipient1@domain recipient2@domain
869 .\" .Ss "On reading mail, and interactive mode" {{{
870 .Ss "On reading mail, and interactive mode"
872 When invoked without addressees \*(UA enters interactive mode in which
874 When used like that the user's system mailbox (see the command
876 for an in-depth description of the different mailbox types that exist)
877 is read in and a one line header of each message therein is displayed.
878 The visual style of this summary of
880 can be adjusted through the variable
882 and the possible sorting criterion via
884 If the initially opened mailbox is empty \*(UA will instead exit
885 immediately (after displaying a message) unless the variable
894 will give a listing of all available commands and
896 will give a summary of some common ones.
897 If the \*(OPal documentation strings are available one can type
899 and see the actual expansion of
901 and what it's purpose is, i.e., commands can be abbreviated
902 (note that POSIX defines some abbreviations, so that the alphabetical
903 order of commands doesn't necessarily relate to the abbreviations; it is
904 possible to define overwrites with the
909 Messages are given numbers (starting at 1) which uniquely identify
910 messages; the current message \(en the
912 \(en will either be the first new message, or the first unread message,
913 or the first message of the mailbox; the option
915 will instead cause usage of the last message for this purpose.
920 ful of header summaries containing the
924 will display only the summaries of the given messages, defaulting to the
928 Messages can be displayed on the user's terminal with the
932 By default the current message
934 is displayed, but like with many other commands it is possible to give
935 a fancy message specification (see
936 .Sx "Specifying messages" ) ,
939 will display all unread messages,
944 will type the messages 1 and 5,
946 will type the messages 1 through 5, and
950 will display the last and the next message, respectively.
953 (a more substantial alias of the standard command
955 will display a header summary of the given message specification list
956 instead of their content, e.g., the following will search for subjects:
959 .Dl ? from """@Some subject to search for"""
962 In the default setup all header fields of a message will be displayed,
963 but this can be changed: either by blacklisting a list of fields via
965 or by whitelisting only a given list with the
968 .Ql Ic \:retain Ns \0date from to cc subject .
969 In order to display all header fields of a message regardless of
970 currently active ignore or retain lists, use the command
974 controls wether and when \*(UA will use the configured
976 for display instead of directly writing to the user terminal
977 (generally speaking).
978 Note that historically the global
980 not only adjusts the list of displayed headers, but also sets
984 Dependent upon the configuration a
985 .Sx "Command line editor"
986 aims at making user experience with the many
989 When reading the system mailbox or when
993 specified a mailbox explicitly prefixed with the special
995 modifier (propagating the mailbox to a primary one) then messages which
996 have been read will be moved to a secondary mailbox, the user's
998 file, automatically when the mailbox is left, either by changing the
999 active mailbox or by quitting \*(UA (also see
1000 .Sx "Message states" )
1001 \(en this automatic moving from a system or primary to the secondary
1002 mailbox is not performed when the variable
1007 After examining a message the user can also
1011 to the sender and all recipients or
1013 exclusively to the sender(s).
1014 Messages can also be
1016 ed (shorter alias is
1018 Note that when replying to or forwarding a message recipient addresses
1019 will be stripped from comments and names unless the option
1022 Deletion causes \*(UA to forget about the message;
1023 This is not irreversible, though, one can
1025 the message by giving its number,
1026 or the \*(UA session can be ended by giving the
1031 To end a mail processing session one may either issue
1033 to cause a full program exit, which possibly includes
1034 automatic moving of read messages to
1036 as well as updating the \*(OPal command line editor history file,
1039 instead in order to prevent any of these actions.
1042 .\" .Ss "HTML mail and MIME attachments" {{{
1043 .Ss "HTML mail and MIME attachments"
1045 Messages which are HTML-only get more and more common and of course many
1046 messages come bundled with a bouquet of MIME attachments.
1047 Whereas \*(UA \*(OPally supports a simple HTML-to-text converter to deal
1048 with HTML messages (see
1049 .Sx "The mime.types files" ) ,
1050 it normally can't deal with any of these itself, but instead programs
1051 need to become registered to deal with specific MIME types or file
1053 These programs may either prepare plain text versions of their input
1054 in order to enable \*(UA to display the content on the terminal,
1055 or display the content themselves, for example in a graphical window.
1058 To install an external handler program for a specific MIME type set an
1060 .Va pipe-TYPE/SUBTYPE
1061 variable; to instead define a handler for a specific file extension set
1064 variable \(en these handlers take precedence.
1065 \*(OPally \*(UA supports mail user agent configuration as defined in
1066 RFC 1524; this mechanism, documented in the section
1067 .Sx "The Mailcap files" ,
1068 will be queried for display or quote handlers if none of the former two
1069 .\" TODO v15-compat "will be" -> "is"
1070 did; it will be the sole source for handlers of other purpose.
1071 A last source for handlers may be the MIME type definition itself, if
1072 the \*(UA specific type-marker extension was used when defining the type
1075 (Many of the builtin MIME types do so by default.)
1079 .Va mime-counter-evidence
1080 can be set to improve dealing with faulty MIME part declarations as are
1081 often seen in real-life messages.
1082 E.g., to display a HTML message inline (that is, converted to a more
1083 fancy plain text representation than the builtin converter is capable to
1084 produce) with either of the text-mode browsers
1088 teach \*(UA about MathML documents and make it display them as plain
1089 text, and to open PDF attachments in an external PDF viewer,
1090 asynchronously and with some other magic attached:
1092 .Bd -literal -offset indent
1093 if $features !@ HTML-FILTER
1094 #set pipe-text/html="elinks -force-html -dump 1"
1095 set pipe-text/html="lynx -stdin -dump -force_html"
1096 # Display HTML as plain text instead
1097 #set pipe-text/html=@
1099 mimetype '@ application/mathml+xml mathml'
1100 set pipe-application/pdf="@&=@ \e
1101 trap \e"rm -f \e\e\e"${NAIL_FILENAME_TEMPORARY}\e\e\e"\e" EXIT;\e
1102 trap \e"trap \e\e\e"\e\e\e" INT QUIT TERM; exit 1\e" \e INT QUIT TERM;\e
1103 xpdf \e"${NAIL_FILENAME_TEMPORARY}\e""
1107 Note: special care must be taken when using such commands as mail
1108 viruses may be distributed by this method: if messages of type
1109 .Ql application/x-sh
1110 or files with the extension
1112 were blindly filtered through the shell, for example, a message sender
1113 could easily execute arbitrary code on the system \*(UA is running on.
1114 For more on MIME, also in respect to sending of messages, see the
1116 .Sx "The mime.types files" ,
1117 .Sx "The Mailcap files"
1122 .\" .Ss "Mailing lists" {{{
1125 \*(UA offers some support to ease handling of mailing lists.
1128 promotes all given arguments to known mailing lists, and
1130 sets their subscription attribute, creating them first as necessary.
1135 automatically, but only resets the subscription attribute.)
1136 Using the commands without arguments will show (a subset of) all
1137 currently defined mailing lists.
1142 can be used to mark out messages with configured list addresses
1143 in the header display.
1146 \*(OPally mailing lists may also be specified as (extended) regular
1147 expressions, which allows matching of many addresses with a single
1149 However, all fully qualified list addresses are matched via a fast
1150 dictionary, whereas expressions are placed in (a) list(s) which is
1151 (are) matched sequentially.
1153 .Bd -literal -offset indent
1154 set followup-to followup-to-honour=ask-yes reply-to-honour=ask-yes
1155 mlist a1@b1.c1 a2@b2.c2 .*@lists.c3$
1156 mlsubscribe a4@b4.c4 exact@lists.c3
1161 .Va followup-to-honour
1163 .Ql Mail-\:Followup-\:To:
1164 header is honoured when the message is being replied to (via
1170 controls wether this header is created when sending mails; it will be
1171 created automatically for a couple of reasons, too, like when the
1173 .Dq mailing list specific
1178 is used to respond to a message with its
1179 .Ql Mail-Followup-To:
1183 A difference in between the handling of known and subscribed lists is
1184 that the address of the sender is usually not part of a generated
1185 .Ql Mail-Followup-To:
1186 when addressing the latter, whereas it is for the former kind of lists.
1187 Usually because there are exceptions: say, if multiple lists are
1188 addressed and not all of them are subscribed lists.
1190 For convenience \*(UA will, temporarily, automatically add a list
1191 address that is presented in the
1193 header of a message that is being responded to to the list of known
1195 Shall that header have existed \*(UA will instead, dependend on the
1197 .Va reply-to-honour ,
1200 for this purpose in order to accept a list administrators' wish that
1201 is supposed to have been manifested like that (but only if it provides
1202 a single address which resides on the same domain as what is stated in
1206 .\" .Ss "Resource files" {{{
1207 .Ss "Resource files"
1209 Upon startup \*(UA reads in several resource files:
1211 .Bl -tag -width ".It Pa _AIL_EXTRA_R_"
1214 System wide initialization file.
1215 Reading of this file can be suppressed, either by using the
1219 command line options, or by setting the environment variable
1220 .Ev NAIL_NO_SYSTEM_RC .
1224 File giving initial commands.
1225 A different file can be chosen by setting the environment variable
1227 Reading of this file can be suppressed with the
1229 command line option.
1231 .It Va NAIL_EXTRA_RC
1232 Can be used to define an optional startup file to be read after all
1233 other resource files.
1234 It can be used to specify settings that are not understood by other
1236 implementations, for example.
1237 This variable is only honoured when defined in a resource file.
1241 The content of these files is interpreted as follows:
1244 .Bl -bullet -compact
1246 A lines' leading whitespace is removed.
1248 Empty lines are ignored.
1250 Any other line is interpreted as a command.
1251 It may be spread over multiple input lines if the newline character is
1253 by placing a backslash character
1255 as the last character of the line; whereas any leading whitespace of
1256 follow lines is ignored, trailing whitespace before a escaped newline
1257 remains in the input.
1259 If the line (content) starts with the number sign
1261 then it is a comment-command \(en a real command! \(en and also ignored.
1262 This command is the only form of comment that is understood.
1268 .Bd -literal -offset indent
1269 # This line is a comment command. And y\e
1270 es, it is really continued here.
1277 .\" .Ss "Character sets" {{{
1278 .Ss "Character sets"
1280 \*(OP \*(UA detects the character set of the terminal by using
1281 mechanisms that are controlled by the
1286 should give an overview); the \*(UA internal variable
1288 will be set to the detected terminal character set accordingly
1289 and will thus show up in the output of the commands
1295 However, a user supplied
1297 value is not overwritten by this detection mechanism: this
1299 must be used if the detection doesn't work properly,
1300 and it may be used to adjust the name of the locale character set.
1301 E.g., on BSD systems one may use a locale with the character set
1302 ISO8859-1, which is not a valid name for this character set; to be on
1303 the safe side, one may set
1305 to the correct name, which is ISO-8859-1.
1308 Note that changing the value doesn't mean much beside that,
1309 since several aspects of the real character set are implied by the
1310 locale environment of the system,
1311 and that stays unaffected by the content of an overwritten
1314 (This is mostly an issue when interactively using \*(UA, though.
1315 It is actually possible to send mail in a completely
1317 locale environment, an option that \*(UA's test-suite uses excessively.)
1320 If no character set conversion capabilities have been compiled into
1323 doesn't include the term
1327 will be the only supported character set,
1328 it is simply assumed that it can be used to exchange 8-bit messages,
1329 and the rest of this section does not apply;
1330 it may however still be necessary to explicitly set it if automatic
1331 detection fails, since in that case it defaults to the mentioned
1332 .\" (Keep in SYNC: ./nail.1:"Character sets", ./nail.h:CHARSET_*!)
1336 When reading messages, their text is converted into
1338 as necessary in order to display them on the users terminal.
1339 Unprintable characters and invalid byte sequences are detected
1340 and replaced by proper substitution characters (unless the variable
1342 was set once \*(UA was started).
1344 .Va charset-unknown-8bit
1345 to deal with another hairy aspect of message interpretation.
1348 When sending messages all their parts and attachments are classified.
1349 Whereas no character set conversion is performed on those parts which
1350 appear to be binary data,
1351 the character set being used must be declared within the MIME header of
1352 an outgoing text part if it contains characters that do not conform to
1353 the set of characters that are allowed by the email standards.
1354 Permissible values for character sets can be declared using the
1358 which defines a catch-all last-resort fallback character set that is
1359 implicitly appended to the list of character-sets in
1363 When replying to a message and the variable
1364 .Va reply-in-same-charset
1365 is set then the character set of the message being replied to is tried
1367 And it is also possible to make \*(UA work even more closely related to
1368 the current locale setting automatically by using the variable
1369 .Va sendcharsets-else-ttycharset ,
1370 please see there for more information.
1373 All the specified character sets are tried in order unless the
1374 conversion of the part or attachment succeeds.
1375 If none of the tried (8-bit) character sets is capable to represent the
1376 content of the part or attachment,
1377 then the message will not be sent and its text will optionally be
1381 In general, if the message
1382 .Dq Cannot convert from a to b
1383 appears, either some characters are not appropriate for the currently
1384 selected (terminal) character set,
1385 or the needed conversion is not supported by the system.
1386 In the first case, it is necessary to set an appropriate
1388 locale and/or the variable
1392 The best results are usually achieved when \*(UA is run in a UTF-8
1393 locale on a UTF-8 capable terminal, in which case the full Unicode
1394 spectrum of characters is available.
1395 In this setup characters from various countries can be displayed,
1396 while it is still possible to use more simple character sets for sending
1397 to retain maximum compatibility with older mail clients.
1400 On the other hand the POSIX standard defines a locale-independent 7-bit
1401 .Dq portable character set
1402 that should be used when overall portability is an issue, the even more
1403 restricted subset named
1404 .Dq portable filename character set
1405 consisting of A-Z, a-z, 0-9, period
1414 .\" .Ss "Message states" {{{
1415 .Ss "Message states"
1417 \*(UA differentiates in between several different message states;
1418 the current state will be reflected in header summary displays if
1420 is configured to do so (via the internal variable
1422 and messages can also be selected and be acted upon depending on their
1424 .Sx "Specifying messages" ) .
1425 When operating on the system mailbox or in primary mailboxes opened with
1430 special actions, like the automatic moving of messages to the secondary
1432 mailbox may be applied when the mailbox is left (also implicitly via
1433 a successful exit of \*(UA, but not if the special command
1435 is used) \(en however, because this may be irritating to users which
1438 mail-user-agents, the default global
1444 variables in order to suppress this behaviour.
1446 .Bl -tag -width ".It Ql _reserved"
1448 Message has neither been viewed nor moved to any other state.
1449 Such messages are retained even in the system mailbox.
1452 Message has neither been viewed nor moved to any other state, but the
1453 message was present already when the mailbox has been opened last:
1454 Such messages are retained even in the system mailbox.
1457 The message has been processed by one of the following commands:
1477 commands may also cause the next message to be marked as read, depending
1483 command is used, messages that are in the system mailbox or in mailboxes
1484 which were opened with the special
1488 state when the mailbox is left will be saved in
1495 The message has been processed by one of the following commands:
1501 can be used to access such messages.
1504 The message has been processed by a
1506 command and it will be retained in its current location.
1509 The message has been processed by one of the following commands:
1515 command is used, messages that are in the system mailbox or in mailboxes
1516 which were opened with the special
1520 state when the mailbox is left will be deleted; they will be saved in
1528 .\" .Ss "Specifying messages" {{{
1529 .Ss "Specifying messages"
1536 can be given a list of message numbers as arguments to apply to a number
1537 of messages at once.
1540 deletes messages 1 and 2,
1543 will delete the messages 1 through 5.
1544 In sorted or threaded mode (see the
1548 will delete the messages that are located between (and including)
1549 messages 1 through 5 in the sorted/threaded order, as shown in the
1552 Multiple colon modifiers can be joined into one, e.g.,
1554 The following special message names exist:
1556 .Bl -tag -width ".It Ar _n_u"
1562 All old messages (any not in state
1587 All answered messages
1592 All messages marked as draft.
1594 \*(OP All messages classified as spam.
1596 \*(OP All messages with unsure spam classification.
1598 The current message, the so-called
1601 The message that was previously the current message.
1603 The parent message of the current message,
1604 that is the message with the Message-ID given in the
1606 field or the last entry of the
1608 field of the current message.
1610 The next previous undeleted message,
1611 or the next previous deleted message for the
1614 In sorted/threaded mode,
1615 the next previous such message in the sorted/threaded order.
1617 The next undeleted message,
1618 or the next deleted message for the
1621 In sorted/threaded mode,
1622 the next such message in the sorted/threaded order.
1624 The first undeleted message,
1625 or the first deleted message for the
1628 In sorted/threaded mode,
1629 the first such message in the sorted/threaded order.
1632 In sorted/threaded mode,
1633 the last message in the sorted/threaded order.
1637 selects the message addressed with
1641 is any other message specification,
1642 and all messages from the thread that begins at it.
1643 Otherwise it is identical to
1648 the thread beginning with the current message is selected.
1653 All messages that were included in the message list for the previous
1656 .It Ar / Ns Ar string
1657 All messages that contain
1659 in the subject field (case ignored).
1666 the string from the previous specification of that type is used again.
1668 .It Xo Op Ar @ Ns Ar name-list Ns
1671 All messages that contain the given case-insensitive search
1673 ession; if the \*(OPal regular expression (see
1675 support is available
1677 will be interpreted as (an extended) one if any of the
1679 (extended) regular expression characters is seen.
1681 .Ar @ Ns Ar name-list
1682 part is missing, the search is restricted to the subject field body,
1685 specifies a comma-separated list of header fields to search, as in
1687 .Dl '@to,from,cc@Someone i ought to know'
1689 In order to search for a string that includes a
1691 (commercial at) character the
1693 is effectively non-optional, but may be given as the empty string.
1694 Some special header fields may be abbreviated:
1708 respectively and case-insensitively.
1713 can be used to search in (all of) the header(s) of the message, and the
1722 can be used to perform full text searches \(en whereas the former
1723 searches only the body, the latter also searches the message header.
1725 This message specification performs full text comparison, but even with
1726 regular expression support it is almost impossible to write a search
1727 expression that savely matches only a specific address domain.
1728 To request that the content of the header is treated as a list of
1729 addresses, and to strip those down to the plain email address which the
1730 search expression is to be matched against, prefix the header name
1731 (abbreviation) with a tilde
1734 .Dl @~f@@a\e.safe\e.domain\e.match$
1738 .Dq any substring matches
1741 header, which will match addresses (too) even if
1743 is set (and POSIX says
1744 .Dq any address as shown in a header summary shall be matchable in this form ) ;
1747 variable is set, only the local part of the address is evaluated
1748 for the comparison, not ignoring case, and the setting of
1750 is completely ignored.
1751 For finer control and match boundaries use the
1753 search expression; the \*(OPal IMAP-style
1755 expression can also be used if substring matches are desired.
1759 \*(OP IMAP-style SEARCH expressions may also be used.
1760 This addressing mode is available with all types of folders;
1761 \*(UA will perform the search locally as necessary.
1762 Strings must be enclosed by double quotes
1764 in their entirety if they contain white space or parentheses;
1765 within the quotes, only backslash
1767 is recognized as an escape character.
1768 All string searches are case-insensitive.
1769 When the description indicates that the
1771 representation of an address field is used,
1772 this means that the search string is checked against both a list
1775 .Bd -literal -offset indent
1776 (\*qname\*q \*qsource\*q \*qlocal-part\*q \*qdomain-part\*q)
1781 and the addresses without real names from the respective header field.
1782 These search expressions can be nested using parentheses, see below for
1786 .Bl -tag -compact -width ".It Ar _n_u"
1787 .It Ar ( criterion )
1788 All messages that satisfy the given
1790 .It Ar ( criterion1 criterion2 ... criterionN )
1791 All messages that satisfy all of the given criteria.
1793 .It Ar ( or criterion1 criterion2 )
1794 All messages that satisfy either
1799 To connect more than two criteria using
1801 specifications have to be nested using additional parentheses,
1803 .Ql (or a (or b c)) ,
1807 .Ql ((a or b) and c) .
1810 operation of independent criteria on the lowest nesting level,
1811 it is possible to achieve similar effects by using three separate
1815 .It Ar ( not criterion )
1816 All messages that do not satisfy
1818 .It Ar ( bcc \*q Ns Ar string Ns Ar \*q )
1819 All messages that contain
1821 in the envelope representation of the
1824 .It Ar ( cc \*q Ns Ar string Ns Ar \*q )
1825 All messages that contain
1827 in the envelope representation of the
1830 .It Ar ( from \*q Ns Ar string Ns Ar \*q )
1831 All messages that contain
1833 in the envelope representation of the
1836 .It Ar ( subject \*q Ns Ar string Ns Ar \*q )
1837 All messages that contain
1842 .It Ar ( to \*q Ns Ar string Ns Ar \*q )
1843 All messages that contain
1845 in the envelope representation of the
1848 .It Ar ( header name \*q Ns Ar string Ns Ar \*q )
1849 All messages that contain
1854 .It Ar ( body \*q Ns Ar string Ns Ar \*q )
1855 All messages that contain
1858 .It Ar ( text \*q Ns Ar string Ns Ar \*q )
1859 All messages that contain
1861 in their header or body.
1862 .It Ar ( larger size )
1863 All messages that are larger than
1866 .It Ar ( smaller size )
1867 All messages that are smaller than
1871 .It Ar ( before date )
1872 All messages that were received before
1874 which must be in the form
1878 denotes the day of the month as one or two digits,
1880 is the name of the month \(en one of
1881 .Ql Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ,
1884 is the year as four digits, e.g.,
1888 All messages that were received on the specified date.
1889 .It Ar ( since date )
1890 All messages that were received since the specified date.
1891 .It Ar ( sentbefore date )
1892 All messages that were sent on the specified date.
1893 .It Ar ( senton date )
1894 All messages that were sent on the specified date.
1895 .It Ar ( sentsince date )
1896 All messages that were sent since the specified date.
1898 The same criterion as for the previous search.
1899 This specification cannot be used as part of another criterion.
1900 If the previous command line contained more than one independent
1901 criterion then the last of those criteria is used.
1905 .\" .Ss "On URL syntax and credential lookup" {{{
1906 .Ss "On URL syntax and credential lookup"
1908 \*(IN For accessing protocol-specific resources usage of Uniform
1909 Resource Locators (URL, RFC 1738) has become omnipresent.
1910 \*(UA expects and understands URLs in the following form;
1913 denote optional parts, optional either because there also exist other
1914 ways to define the information in question or because support of the
1915 part is protocol-specific (e.g.,
1917 is used by the IMAP protocol but not by POP3);
1922 are specified they must be given in URL percent encoded form (RFC 3986;
1930 .Dl PROTOCOL://[USER[:PASSWORD]@]server[:port][/path]
1933 Note that these \*(UA URLs most often don't conform to any real
1934 standard, but instead represent a normalized variant of RFC 1738 \(en
1935 they are not used in data exchange but only ment as a compact,
1936 easy-to-use way of defining and representing information in
1937 a well-known notation.
1940 Many internal variables of \*(UA exist in multiple versions, called
1941 variable chains for the rest of this document: the plain
1946 .Ql variable-USER@HOST .
1953 had been specified in the respective URL, otherwise it refers to the plain
1959 that had been found when doing the user chain lookup as is described
1962 will never be in URL percent encoded form, wether it came from an URL or
1963 not; i.e., values of
1964 .Sx "INTERNAL VARIABLES"
1965 must not be URL percent encoded.
1968 For example, wether an hypothetical URL
1969 .Ql smtp://hey%3Ayou@our.house
1970 had been given that includes a user, or wether the URL was
1971 .Ql smtp://our.house
1972 and the user had been found differently, to lookup the variable chain
1973 .Va smtp-use-starttls
1974 \*(UA first looks for wether
1975 .Ql smtp-\:use-\:starttls-\:hey:you@our.house
1976 is defined, then wether
1977 .Ql smtp-\:use-\:starttls-\:our.house
1978 exists before finally ending up looking at the plain variable itself.
1981 \*(UA obeys the following logic scheme when dealing with the
1982 necessary credential informations of an account:
1988 has been given in the URL the variables
1992 are looked up; if no such variable(s) can be found then \*(UA will,
1993 when enforced by the \*(OPal variables
1994 .Va netrc-lookup-HOST
2001 specific entry which provides a
2003 name: this lookup will only succeed if unambiguous (one possible matching
2007 If there is still no
2009 then \*(UA will fall back to the user who is supposed to run \*(UA:
2010 either the name that has been given with the
2012 command line option (or, equivalently, but with less precedence, the
2013 environment variable
2018 The identity of this user has been fixated during \*(UA startup and is
2019 known to be a valid user on the current host.
2022 Authentication: unless otherwise noted this will lookup the
2023 .Va PROTOCOL-auth-USER@HOST , PROTOCOL-auth-HOST , PROTOCOL-auth
2024 variable chain, falling back to a protocol-specific default should this
2030 has been given in the URL, then if the
2032 has been found through the \*(OPal
2034 then that may have already provided the password, too.
2035 Otherwise the variable chain
2036 .Va password-USER@HOST , password-HOST , password
2037 is looked up and used if existent.
2039 \*(OP Then if any of the variables of the chain
2040 .Va agent-shell-lookup-USER@HOST , agent-shell-lookup-HOST , \
2042 is set the shell command specified therein is run and the output (less
2043 newline characters) will be used as the password.
2044 It is perfectly valid for such an agent to simply not return any data,
2045 in which case the password lookup is continued somewhere else;
2046 Any command failure is treated as a hard error, however.
2048 Afterwards the complete \*(OPal variable chain
2049 .Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup
2053 cache is searched for a password only (multiple user accounts for
2054 a single machine may exist as well as a fallback entry without user
2055 but with a password).
2057 If at that point there is still no password available, but the
2058 (protocols') chosen authentication type requires a password, then in
2059 interactive mode the user will be prompted on the terminal.
2064 S/MIME verification works relative to the values found in the
2068 header field(s), which means that the values of
2069 .Va smime-sign , smime-sign-cert , smime-sign-include-certs
2071 .Va smime-sign-message-digest
2072 will not be looked up using the
2076 chains from above but instead use the corresponding values from the
2077 message that is being worked on.
2078 In unusual cases multiple and different
2082 combinations may therefore be involved \(en on the other hand those
2083 unusual cases become possible.
2084 The usual case is as short as:
2087 .Dl set smtp=smtp://USER:PASS@HOST smtp-use-starttls \e
2088 .Dl \ \ \ \ smime-sign smime-sign-cert=+smime.pair
2093 contains complete example configurations.
2096 .\" .Ss "Command line editor" {{{
2097 .Ss "Command line editor"
2099 \*(OP \*(UA can be configured to support a command line editor and
2100 command history lists which are saved in between sessions.
2101 One may link against fully-fledged external libraries
2102 .Pf ( Xr readline 6 ,
2104 ) or use \*(UA's own command line editor NCL (Nail-Command-Line)
2105 instead, which should work in all environments which comply to the
2106 ISO C standard (ISO/IEC 9899:1990/Amendment 1:1995).
2107 When an external library is used, interactive behaviour of \*(UA relies
2108 on that library and may not correspond one-to-one to what is described
2112 Regardless of the actually used command line editor
2114 entries will be created for lines entered in command mode only, and
2115 creation of such an entry can be forcefully suppressed by starting the
2116 line with a space character.
2119 handling is by itself an optional feature and may therefore not be
2121 For more information see the documentation of the variables
2125 .Va history-gabby-persist ,
2128 .Va line-editor-disable .
2129 And there is also the \*(OPal
2131 will can be set to cause overall screen resets when \*(UA releases the
2132 terminal in interactive mode.
2135 The builtin \*(UA command line editor supports the following operations;
2138 stands for the combination of the
2140 key plus the mentioned character, e.g.,
2143 .Dq hold down control key and press the A key :
2146 .Bl -tag -compact -width "Ql _M"
2148 Go to the start of the line.
2150 Move the cursor backward one character.
2152 Forward delete the character under the cursor;
2153 quits \*(UA if used on the empty line unless the
2157 Go to the end of the line.
2159 Move the cursor forward one character.
2162 Cancel current operation, full reset.
2163 If there is an active history search or tabulator expansion then this
2164 command will first reset that, reverting to the former line content;
2165 thus a second reset is needed for a full reset in this case.
2166 In all cases \*(UA will reset a possibly used multibyte character input
2172 backward delete one character.
2176 .Dq horizontal tabulator :
2177 try to expand the word before the cursor.
2179 .Dq tabulator-completion
2180 as is known from the
2182 but really means the usual \*(UA expansion, as documented for
2184 yet it involves shell expansion as a last step, too.)
2189 complete this line of input.
2191 Delete all characters from the cursor to the end of the line.
2195 \*(OP Go to the next history entry.
2200 \*(OP Go to the previous history entry.
2202 \*(OP Complete the current line from (the remaining older) history entries.
2209 Delete the characters from the one preceding the cursor to the preceding
2212 Move the cursor forward one word boundary.
2214 Move the cursor backward one word boundary.
2218 If problems with commands that are based upon rightwise movement are
2219 encountered, adjustments of the option
2220 .Va line-editor-cursor-right
2221 may solve the problem, as documented for it.
2224 If the terminal produces key sequences which are compatible with
2226 then the left and right cursor keys will map to
2230 respectively, the up and down cursor keys will map to
2234 and the Home/End/PgUp/PgDown keys will call the
2236 command with the respective arguments
2242 (i.e., perform scrolling through the header summary list).
2243 Also the up and down cursor keys should invoke
2245 for up- and downwards movement if they are used while the
2250 .\" .Ss "Coloured display" {{{
2251 .Ss "Coloured display"
2253 \*(OP \*(UA can be configured to support a coloured display and font
2255 Colour usage depends on the value of the environment variable
2257 if that is not set or set to the value
2259 then this section doesn't apply, if the value includes the string
2261 or if it can be found (case-insensitively) in the variable
2263 then \*(UA will assume a colour-enabled display, but otherwise
2264 a monochrome display is assumed.
2267 On top of what \*(UA knows about the terminal the boolean variable
2269 defines wether colour and font attribute sequences should also be
2270 generated when the output of a command needs to go through the
2275 This is not enabled by default because different pager programs need
2276 different command line switches or other configuration in order to
2277 support those colour sequences.
2278 \*(UA knows about some widely used pagers and in a clean environment
2279 it is often enough to simply set
2281 please refer to that variable for more on this topic.
2286 is set then any active usage of colour and font attribute sequences
2287 is suppressed, but without affecting possibly established
2292 To define and control colours and font attributes a single multiplexer
2293 command family exists:
2295 shows or defines colour mappings for the given colour type (e.g.,
2298 can be used to remove mappings of a given colour type.
2299 Since colours are only available in interactive mode, it may make
2300 sense to conditionalize the colour setup by encapsulating it with
2303 .Bd -literal -offset indent
2305 colour iso view-msginfo ft=bold,fg=green
2306 colour iso view-header ft=bold,fg=red "from,subject"
2307 colour iso view-header fg=red
2309 uncolour iso view-header from,subject
2310 colour iso view-header ft=bold,fg=magenta,bg=cyan
2311 colour 256 view-header ft=bold,fg=208,bg=230 subject,from
2312 colour mono view-header ft=bold
2313 colour mono view-header ft=bold,ft=reverse subject,from
2317 .\" }}} (DESCRIPTION)
2320 .\" .Sh COMMANDS {{{
2323 Each command is typed on a line by itself,
2324 and may take arguments following the command word.
2325 The command need not be typed in its entirety \(en
2326 the first command which matches the typed prefix is used.
2327 An \(en alphabetically \(en sorted list of commands can be shown
2334 when given an argument, will show a documentation string for the
2335 command matching the expanded argument, as in
2337 which should be a shorthand of
2339 documentation strings are however \*(OPal.
2342 For commands which take message lists as arguments, the next message
2343 forward that satisfies the command's requirements will be used shall no
2344 explicit message list have been specified.
2345 If there are no messages forward of the current message,
2346 the search proceeds backwards,
2347 and if there are no good messages at all,
2349 .Dq no applicable messages
2350 and aborts the command.
2351 The arguments to commands can be quoted, using the following methods:
2354 .Bl -bullet -compact -offset indent
2356 An argument can be enclosed between paired double-quotes
2361 any white space, shell word expansion, or backslash characters (except
2362 as described next) within the quotes are treated literally as part of
2364 A double-quote will be treated literally within single-quotes and vice
2366 Inside such a quoted string the actually used quote character can be
2367 used nonetheless by escaping it with a backslash
2373 An argument that is not enclosed in quotes, as above, can usually still
2374 contain space characters if those spaces are backslash-escaped, as in
2378 A backslash outside of the enclosing quotes is discarded
2379 and the following character is treated literally as part of the argument.
2382 An unquoted backslash at the end of a command line is discarded and the
2383 next line continues the command.
2387 Filenames, where expected, are subsequently subjected to the following
2388 transformations, in sequence:
2391 .Bl -bullet -compact -offset indent
2393 If the filename begins with an unquoted plus sign, and the
2395 variable is defined,
2396 the plus sign will be replaced by the value of the
2398 variable followed by a slash.
2401 variable is unset or is set to null, the filename will be unchanged.
2404 Shell word expansions are applied to the filename.
2405 .\" TODO shell word expansion shell expand fexpand FEXP_NSHELL
2406 .Sy Compatibility note:
2407 on the long run support for complete shell word expansion will be
2408 replaced by an internally implemented restricted expansion mechanism in
2409 order to circumvent possible security impacts through shell expansion.
2410 Expect that a growing number of program parts only support this
2413 Meta expansions are applied to the filename: leading tilde characters
2415 will be replaced by the expansion of
2417 and any occurrence of
2421 will be replaced by the expansion of the variable, if possible;
2422 \*(UA internal as well as environmental (shell) variables can be
2423 accessed through this mechanism.
2424 In order to include a raw
2426 character precede it with a backslash
2428 to include a backslash double it.
2429 If more than a single pathname results from this expansion and the
2430 command is expecting one file, an error results.
2432 Note that in interactive display context, in order to allow simple
2433 value acceptance (typing
2435 backslash quoting is performed automatically as necessary, e.g., a file
2436 .Ql diet\e is \ecurd.txt
2437 will be displayed as
2438 .Ql diet\e\e is \e\ecurd.txt .
2442 The following commands are available:
2444 .Bl -tag -width ".Ic _ccount"
2451 ) command which follows.
2455 The comment-command causes the entire line to be ignored.
2457 this really is a normal command which' purpose is to discard its
2460 indicating special character, which means that, e.g., trailing comments
2461 on a line are not possible.
2465 Goes to the next message in sequence and types it
2471 Display the preceding message, or the n'th previous message if given
2472 a numeric argument n.
2476 Show the current message number (the
2481 Show a brief summary of commands.
2482 \*(OP Given an argument a synopsis for the command in question is
2483 shown instead; commands can be abbreviated in general and this command
2484 can be used to see the full expansion of an abbreviation including the
2485 synopsis, try, e.g.,
2490 and see how the output changes.
2500 Interprets the remainder of the word as a macro name and passes it
2505 is a shorter synonym for
2506 .Ql call Ar mymacro .
2510 (ac) Creates, selects or lists (an) account(s).
2511 An account is a group of commands and variable settings which together
2512 usually arrange the environment for the purpose of creating a system login.
2513 Without any argument a listing of all defined accounts and their content
2515 A specific account can be activated by giving solely its name, resulting
2516 in the system mailbox or inbox of that account to be activated as via an
2517 explicit use of the command
2519 The two argument form is identical to defining a macro as via
2522 .Bd -literal -offset indent
2526 set from="myname@myisp.example (My Name)"
2527 set smtp=smtp://mylogin@smtp.myisp.example
2531 creates an account named
2533 which can later be selected by specifying
2537 (case-insensitive) always exists.
2539 can be used to localize account settings \(en different to normal macros
2540 the settings will be reverted once the account is switched off.
2541 Accounts can be deleted via
2546 (a) With no arguments, shows all currently-defined aliases.
2547 With one argument, shows that alias.
2548 With more than one argument,
2549 creates a new alias or appends to an existing one.
2551 can be used to delete aliases.
2555 (alt) Manage a list of alternate addresses / names of the active user,
2556 members of which will be removed from recipient lists when replying to
2559 variable is not set).
2560 If arguments are given the set of alternate names is replaced by them,
2561 without arguments the current set is displayed.
2565 Takes a message list and marks each message as having been answered.
2566 This mark has no technical meaning in the mail system;
2567 it just causes messages to be marked in the header summary,
2568 and makes them specially addressable.
2572 Calls a macro that has been created via
2577 (ch) Change the working directory to
2579 or the given argument.
2585 \*(OP Only applicable to S/MIME signed messages.
2586 Takes a message list and a file name and saves the certificates
2587 contained within the message signatures to the named file in both
2588 human-readable and PEM format.
2589 The certificates can later be used to send encrypted messages to the
2590 respective message senders by setting
2591 .Va smime-encrypt-USER@HOST
2596 (ch) Change the working directory to
2598 or the given argument.
2604 Only applicable to threaded mode.
2605 Takes a message list and makes all replies to these messages invisible
2606 in header summaries, unless they are in state
2612 \*(OP Manage colour mappings for the type of colour given as the
2613 (case-insensitive) first argument, which must be one of
2615 for 256-colour terminals,
2620 for the standard 8-colour ANSI / ISO 6429 color palette and
2624 for monochrome terminals.
2625 Monochrome terminals cannot deal with colours, but only (some) font
2629 Without further arguments the list of all currently defined mappings for
2630 the given colour type is shown.
2631 Otherwise the second argument defines the mappable slot, the third
2632 argument a (comma-separated list of) colour and font attribute
2633 specification(s), and the optional fourth argument can be used to
2634 specify a precondition: if conditioned mappings exist they are tested in
2635 (creation) order unless a (case-insensitive) match has been found, and
2636 the default mapping (if any has been established) will only be chosen as
2638 The types of precondition available depend on the mappable slot, the
2639 following of which exist:
2642 .Bl -tag -compact -width view-partinfo
2644 Mappings prefixed with
2646 are used in header summaries, and they all understand the preconditions
2648 (the current message) and
2650 for elder messages (only honoured in conjunction with
2651 .Va datefield-markout-older ) .
2652 This mapping is used for the
2654 that can be created with the
2658 formats of the variable
2661 For the complete header summary line except the
2663 and the thread structure.
2665 For the thread structure which can be created with the
2667 format of the variable
2671 Mappings prefixed with
2673 are used when displaying messages.
2674 This mapping is used for so-called
2676 lines, which are MBOX file format specific header lines.
2679 A comma-separated list of headers to which the mapping applies may be
2680 given as a precondition; if the \*(OPal regular expression support is
2681 available then if any of the
2683 (extended) regular expression characters is seen the precondition will
2684 be evaluated as (an extended) one.
2686 For the introductional message info line.
2687 .It Cd view-partinfo
2688 For MIME part info lines.
2692 The following (case-insensitive) colour definitions and font attributes
2693 are understood, multiple of which can be specified in a comma-separated
2703 It is possible (and often applicable) to specify multiple font
2704 attributes for a single mapping.
2707 foreground colour attribute:
2717 To specify a 256-color mode a decimal number colour specification in
2718 the range 0 to 255, inclusive, is supported, and interpreted as follows:
2720 .Bl -tag -compact -width "999 - 999"
2722 the standard ISO 6429 colors, as above.
2724 high intensity variants of the standard colors.
2726 216 colors in tuples of 6.
2728 grayscale from black to white in 24 steps.
2730 .Bd -literal -offset indent
2732 fg() { printf "\e033[38;5;${1}m($1)"; }
2733 bg() { printf "\e033[48;5;${1}m($1)"; }
2735 while [ $i -lt 256 ]; do fg $i; i=$(($i + 1)); done
2736 printf "\e033[0m\en"
2738 while [ $i -lt 256 ]; do bg $i; i=$(($i + 1)); done
2739 printf "\e033[0m\en"
2743 background colour attribute (see
2745 for possible values).
2749 Mappings may be removed with the command
2751 For a generic overview see the section
2752 .Sx "Coloured display" .
2757 (C) Copy messages to files whose names are derived from the author of
2758 the respective message and don't mark them as being saved;
2759 otherwise identical to
2764 (c) Copy messages to the named file and don't mark them as being saved;
2765 otherwise identical to
2770 With no arguments, shows all currently-defined custom headers.
2771 With one argument, shows that custom header.
2772 With more than one argument, creates a new or replaces an existing
2773 custom header with the name given as the first argument, the content of
2774 which being defined by the concatenated remaining arguments.
2776 can be used to delete custom headers.
2777 \*(ID Overwriting of automatically managed headers is neither supported
2779 Defined custom headers will be injected into newly composed or forwarded
2782 .Dl customhdr OpenPGP id=12345678; url=http://www.YYY.ZZ
2786 may also be used to inject custom headers; it is covered by
2791 Show the name of the current working directory.
2795 \*(OP For unencrypted messages this command is identical to
2797 Encrypted messages are first decrypted, if possible, and then copied.
2801 \*(OP For unencrypted messages this command is identical to
2803 Encrypted messages are first decrypted, if possible, and then copied.
2807 Without arguments the current list of macros, including their content,
2808 is shown, otherwise a macro is defined.
2809 A macro definition is a sequence of commands in the following form:
2810 .Bd -literal -offset indent
2819 A defined macro can be invoked explicitly by using the
2823 commands, or implicitly by setting the
2826 .Va folder-hook-FOLDER
2828 Note that interpretation of
2830 depends on how (i.e.,
2832 normal macro, folder hook, account switch) the macro is invoked.
2833 Macros can be deleted via
2835 .Bd -filled -compact -offset indent
2837 Macro behaviour, including option localization, will change in v15.
2838 To be on the absolutely safe side and avoid any surprises it may be wise
2839 to use wrappers that depend on the program version, e.g.,:
2841 .Bd -literal -offset indent
2842 if $version-major < 15
2848 echo "Please reverify macro name (post v15)"
2855 (d) Marks the given message list as
2857 Deleted messages will neither be saved in
2859 nor will they be available for most other commands.
2871 Deletes the current message and displays the next message.
2872 If there is no next message, \*(UA says
2879 up or down by one message when given
2883 argument, respectively.
2887 Takes a message list and marks each given message as a draft.
2888 This mark has no technical meaning in the mail system;
2889 it just causes messages to be marked in the header summary,
2890 and makes them specially addressable.
2894 (ec) Echoes its arguments,
2895 resolving special names as documented for the command
2897 The escape sequences
2909 are interpreted just as they are by
2911 (proper quoting provided).
2915 (e) Point the text editor (as defined in
2917 at each message from the given list in turn.
2918 Modified contents are discarded unless the
2925 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
2926 conditional \(em if the condition of a preceeding
2928 was false, check the following condition and execute the following block
2929 if it evaluates true.
2934 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
2935 conditional \(em if none of the conditions of the preceeding
2939 commands was true, the
2945 (en) Marks the end of an
2946 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
2947 conditional execution block.
2951 \*(OP Since \*(UA uses the console as a user interface it can happen
2952 that messages scroll by too fast to become recognized.
2953 Optionally an error message ring queue is available which stores
2954 duplicates of any error message and notifies the user in interactive
2955 sessions whenever a new error has occurred.
2956 The queue is finite: if its maximum size is reached any new message
2957 replaces the eldest.
2960 can be used to manage this message queue: if given
2962 or no argument the queue will be displayed and cleared,
2964 will only clear all messages from the queue.
2968 (ex or x) Exit from \*(UA without changing the active mailbox and skip
2969 any saving of messages in
2971 as well as a possibly tracked command line editor history file.
2975 Show the list of features that have been compiled into \*(UA.
2976 (Outputs the contents of the variable
2983 but open the mailbox readonly.
2987 (fi) The file command switches to a new mailbox.
2988 Without arguments it shows status information of the current mailbox.
2989 If an argument is given, it will write out changes (such as deletions)
2990 the user has made and open a new mailbox.
2991 Some special conventions are recognized for the
2995 .Bl -tag -compact -offset indent -width ".Ar %:__lespec"
2997 (number sign) means the previous file,
2999 (percent sign) means the invoking user's system mailbox,
3001 means the system mailbox of
3003 (and never the value of
3005 regardless of its actual setting),
3007 (ampersand) means the invoking user's
3017 expands to the same value as
3019 but the file is handled as a system mailbox by, e.g., the
3023 commands, meaning that messages that have been read in the current
3024 session will be moved to the
3026 mailbox instead of simply being flagged as read.
3029 If the name matches one of the strings defined with the command
3031 it is replaced by its long form and expanded.
3032 If the name ends with
3037 it is treated as being compressed with
3042 respectively, and transparently handled through an intermediate
3043 (un)compression step (using a temporary file) with the according
3044 facility, sufficient support provided.
3045 Likewise, if the named file doesn't exist, but a file with one of the
3046 mentioned compression extensions does, then the name is automatically
3047 expanded and the compressed file is used.
3049 Otherwise, if the name ends with an extension for which
3050 .Va file-hook-load-EXTENSION
3052 .Va file-hook-save-EXTENSION
3053 variables are set, then the given hooks will be used to load and save
3055 and \*(UA will work with an intermediate temporary file.
3057 MBOX files (flat file-based mailboxes) are generally locked during file
3058 operations in order to avoid inconsistencies due to concurrent
3060 \*(OPal Mailbox files which \*(UA treats as system or primary mailboxes
3061 will also be protected by so-called dotlock files, the traditional way
3062 of mail spool file locking: for any file
3066 will be created for the duration of the synchronization \(em
3067 as necessary a privilege-separated dotlock child process will be used
3068 to accommodate for necessary privilege adjustments in order to create
3069 the dotlock file in the same directory
3070 and with the same user and group identities as the file of interest.
3073 for fine-tuning the handling of MBOX files.
3077 refers to a directory with the subdirectories
3082 then it is treated as a folder in
3087 .Dl \*(IN protocol://[user[:password]@]host[:port][/path]
3088 .Dl \*(OU protocol://[user@]host[:port][/path]
3090 is taken as an Internet mailbox specification.
3091 The \*(OPally supported protocols are
3095 (POP3 with SSL/TLS encrypted transport).
3098 part is valid only for IMAP; there it defaults to
3100 Also see the section
3101 .Sx "On URL syntax and credential lookup" .
3105 contains special characters, in particular
3109 they must be escaped in URL notation \(en the command
3111 can be used to show the necessary conversion.
3115 Takes a message list and marks the messages as
3117 ged for urgent/special attention.
3118 This mark has no technical meaning in the mail system;
3119 it just causes messages to be highlighted in the header summary,
3120 and makes them specially addressable.
3129 With no arguments, list the names of the folders in the folder directory.
3130 With an existing folder as an argument,
3131 lists the names of folders below the named folder.
3137 but saves the message in a file named after the local part of the first
3138 recipient's address (instead of in
3145 but saves the message in a file named after the local part of the first
3146 recipient's address (instead of in
3153 but responds to all recipients regardless of the
3158 .It Ic followupsender
3161 but responds to the sender only regardless of the
3177 (f) Takes a list of message specifications and displays a summary of
3178 their message headers, as via
3180 An alias of this command is
3183 .Sx "Specifying messages" .
3189 but saves the message in a file named after the local part of the
3190 recipient's address (instead of in
3195 Takes a message and the address of a recipient
3196 and forwards the message to him.
3197 The text of the original message is included in the new one,
3198 with the value of the
3200 variable preceding it.
3205 commands specify which header fields are included in the new message.
3206 Only the first part of a multipart message is included unless the
3207 .Va forward-as-attachment
3211 is set recipient addresses will be stripped from comments, names etc.
3215 Specifies which header fields are to be ignored with the command
3217 This command has no effect when the
3218 .Va forward-as-attachment
3223 Specifies which header fields are to be retained with the command
3228 This command has no effect when the
3229 .Va forward-as-attachment
3234 Define or list command aliases, so-called ghosts.
3235 Without arguments a list of all currently known aliases is shown.
3236 With one argument the expansion of the given alias is shown.
3237 With two or more arguments a command alias is defined or updated: the
3238 first argument is the name under which the remaining command line should
3239 be accessible, the content of which can be just about anything.
3240 A ghost can be used everywhere a normal command can be used, but always
3241 takes precedence; any arguments that are given to the command alias are
3242 joined onto the alias content, and the resulting string forms the
3243 command line that is, in effect, executed.
3246 .Bd -literal -offset indent
3248 `ghost': no such alias: "xx"
3251 ghost xx "echo hello,"
3260 (h) Show the current group of headers, the size of which depends on
3263 and the style of which can be adjusted with the variable
3265 If a message-specification is given the group of headers containing the
3266 first message therein is shown and the message at the top of the screen
3281 the list of history entries;
3284 argument selects and shows the respective history entry \(en
3287 to accept it, and the history entry will become the new history top.
3288 The default mode if no arguments are given is
3295 Takes a message list and marks each message therein to be saved in the
3296 user's system mailbox instead of in
3298 Does not override the
3301 \*(UA deviates from the POSIX standard with this command, because a
3303 command issued after
3305 will display the following message, not the current one.
3310 (i) Part of the nestable
3311 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3312 conditional execution construct \(em if the given condition is true then
3313 the encapsulated block is executed.
3314 POSIX only supports the (case-insensitive) conditions
3319 end, all remaining conditions are non-portable extensions; note that
3320 falsely specified conditions cause the execution of the entire
3321 conditional construct until the (matching) closing
3323 command to be suppressed.
3324 The syntax of the nestable
3326 conditional execution construct requires that each condition and syntax
3327 element is surrounded by whitespace.
3329 .Bd -literal -offset indent
3338 The (case-insensitive) condition
3340 erminal will evaluate to true if the standard input is a terminal, i.e.,
3341 in interactive sessions.
3342 Another condition can be any boolean value (see the section
3343 .Sx "INTERNAL VARIABLES"
3344 for textual boolean representations) to mark an enwrapped block as
3347 .Dq always execute .
3348 It is possible to check a variable for existence or compare its
3349 expansion against a user given value or another variable via the
3351 .Pf ( Dq variable next )
3352 conditional trigger character.
3353 The available comparison operators are
3357 (less than or equal to),
3363 (greater than or equal to),
3367 (is substring of) and
3369 (is not substring of).
3370 The values of the left and right hand side are treated as strings and
3371 are compared 8-bit byte-wise, ignoring case according to the rules of
3372 the US-ASCII encoding (therefore, dependend on the active locale,
3373 possibly producing false results for strings in the locale encoding).
3374 Except for the substring checks the comparison will instead be performed
3375 arithmetically if both, the user given value as well as the variable
3376 content, can be parsed as numbers (integers).
3377 An unset variable is treated as the empty string.
3380 When the \*(OPal regular expression support is available, the additional
3386 They treat the right hand side as an extended regular expression that is
3387 matched case-insensitively and according to the active
3389 locale, meaning that strings in the locale encoding should be matched
3393 Conditions can be joined via AND-OR lists (where the AND operator is
3395 and the OR operator is
3397 which have equal precedence and will be evaluated with left
3398 associativity, thus using the same syntax that is known for the
3400 It is also possible to form groups of conditions and lists by enclosing
3401 them in pairs of brackets
3402 .Ql [\ \&.\&.\&.\ ] ,
3403 which may be interlocked within each other, and also be joined via
3407 The results of individual conditions and entire groups may be modified
3408 via unary operators: the unary operator
3410 will reverse the result.
3412 .Bd -literal -offset indent
3416 if $ttycharset == "UTF-8"
3417 echo *ttycharset* is set to UTF-8, case-insensitively
3421 echo These two variables are equal
3423 if $version-major >= 15
3424 echo Running a new version..
3425 if $features =@ "regex"
3426 if $TERM =~ "^xterm\&.*"
3427 echo ..in an X terminal
3430 if [ [ true ] && [ [ $debug ] || [ $verbose ] ] ]
3433 if true && $debug || $verbose
3434 echo Left associativity, as is known from the shell
3436 if ! ! true && ! [ ! $debug && ! $verbose ]
3437 echo Unary operator support
3445 Without arguments the list of ignored header fields is shown,
3446 otherwise the given list of header fields is added to the ignore list:
3447 Header fields in the ignore list are not shown on the terminal when
3448 a message is displayed.
3449 To display a message in its entirety, use the commands
3460 Shows the names of all available commands, alphabetically sorted.
3464 This command can be used to localize changes to variables, meaning that
3465 their state will be reverted to the former one once the covered scope
3467 It can only be used inside of macro definition blocks introduced by
3471 and is interpreted as a boolean (string, see
3472 .Sx "INTERNAL VARIABLES" ) ;
3475 of an account is left once it is switched off again.
3476 .Bd -literal -offset indent
3477 define temporary_settings {
3492 enables change localization and calls
3494 which explicitly resets localization, then any value changes within
3496 will still be reverted by
3501 Reply to messages that come in via known
3504 .Pf ( Ic mlsubscribe )
3505 mailing lists, or pretend to do so (see
3506 .Sx "Mailing lists" ) :
3509 functionality this will actively resort and even remove message
3510 recipients in order to generate a message that is supposed to be sent to
3512 For example it will also implicitly generate a
3513 .Ql Mail-Followup-To:
3514 header if that seems useful, regardless of the setting of the variable
3521 but saves the message in a file named after the local part of the first
3522 recipient's address (instead of in
3527 (m) Takes a (list of) recipient address(es) as (an) argument(s),
3528 or asks on standard input if none were given;
3529 then collects the remaining mail content and sends it out.
3533 (mb) The given message list is to be sent to
3535 when \*(UA is quit; this is the default action unless the
3538 \*(ID This command can only be used in a system mailbox (see
3543 Without any arguments the content of the MIME type cache will displayed.
3544 Otherwise each argument defines a complete MIME type specification of
3545 a type that shall be added (prepended) to the cache.
3546 In any event MIME type sources are loaded first as necessary \(en
3547 .Va mimetypes-load-control
3548 can be used to fine-tune which sources are actually loaded.
3549 Refer to the section on
3550 .Sx "The mime.types files"
3551 for more on MIME type specifications and this topic in general.
3552 MIME type unregistration and cache resets can be triggered with
3557 Without arguments the list of all currently defined mailing lists
3558 (and their attributes, if any) is shown.
3559 Otherwise all given arguments (which need not be quoted except for
3560 whitespace) will be added and henceforth be recognized as mailing lists.
3561 Mailing lists may be removed via the command
3564 If the \*(OPal regular expression support is available then mailing
3565 lists may also be specified as (extended) regular expressions (see
3571 Without arguments the list of all currently defined mailing lists which
3572 have a subscription attribute is shown.
3573 Otherwise this attribute will be set for all given mailing lists,
3574 newly creating them as necessary (as via
3576 Subscription attributes may be removed via the command
3585 but moves the messages to a file named after the local part of the
3586 sender address of the first message (instead of in
3593 but marks the messages for deletion if they were transferred
3600 but also displays ignored header fields and all MIME parts.
3608 on the given messages, even in non-interactive mode and as long as the
3609 standard output is a terminal.
3615 \*(OP When used without arguments or if
3617 has been given the content of the
3619 cache is shown, loading it first as necessary,
3622 then the cache will only be initialized and
3624 will remove its contents.
3625 Note that \*(UA will try to load the file only once, use
3626 .Ql Ic netrc Ns \:\0\:clear
3627 to unlock further attempts.
3631 .Sx "On URL syntax and credential lookup" ;
3633 .Sx "The .netrc file"
3634 documents the file format in detail.
3638 Checks for new mail in the current folder without committing any changes
3640 If new mail is present, a message is shown.
3644 the headers of each new message are also shown.
3652 Goes to the next message in sequence and types it.
3653 With an argument list, types the next matching message.
3667 If the current folder is accessed via a network connection, a
3669 command is sent, otherwise no operation is performed.
3675 but also displays ignored header fields and all MIME parts.
3683 on the given messages, even in non-interactive mode and as long as the
3684 standard output is a terminal.
3692 but also pipes ignored header fields and all parts of MIME
3693 .Ql multipart/alternative
3698 (pi) Takes a message list and a shell command
3699 and pipes the messages through the command.
3700 Without an argument the current message is piped through the command
3707 every message is followed by a formfeed character.
3728 (q) Terminates the session, saving all undeleted, unsaved messages in
3731 preserving all messages marked with
3735 or never referenced in the system mailbox,
3736 and removing all other messages from the system mailbox.
3737 If new mail has arrived during the session,
3739 .Dq You have new mail
3741 If given while editing a mailbox file with the command line flag
3743 then the edit file is rewritten.
3744 A return to the shell is effected,
3745 unless the rewrite of edit file fails,
3746 in which case the user can escape with the exit command.
3760 Removes the named folders.
3761 The user is asked for confirmation in interactive mode.
3765 Takes the name of an existing folder
3766 and the name for the new folder
3767 and renames the first to the second one.
3768 Both folders must be of the same type.
3772 (R) Reply to originator.
3773 Does not reply to other recipients of the original message.
3775 will exchange this command with
3779 is set the recipient address will be stripped from comments, names etc.
3783 (r) Take a message and group-responds to it by addressing the sender
3786 .Va followup-to-honour ,
3789 .Va recipients-in-cc
3790 influence response behaviour.
3793 offers special support for replying to mailing lists.
3796 is set recipient addresses will be stripped from comments, names etc.
3809 but initiates a group-reply regardless of the value of
3816 but responds to the sender only regardless of the value of
3823 but does not add any header lines.
3824 This is not a way to hide the sender's identity,
3825 but useful for sending a message again to the same recipients.
3829 Takes a list of messages and a user name
3830 and sends each message to the named user.
3832 and related header fields are prepended to the new copy of the message.
3850 .It Ic respondsender
3856 (ret) Without arguments the list of retained header fields is shown,
3857 otherwise the given list of header fields is added to the retain list:
3858 Header fields in the retain list are shown on the terminal when
3859 a message is displayed, all other header fields are suppressed.
3860 To display a message in its entirety, use the commands
3869 takes precedence over the mentioned.
3875 but saves the messages in a file named after the local part of the
3876 sender of the first message instead of (in
3878 and) taking a filename argument.
3882 (s) Takes a message list and a filename and appends each message in turn
3883 to the end of the file.
3884 If no filename is given, the
3887 The filename in quotes, followed by the generated character count
3888 is echoed on the user's terminal.
3889 If editing a system mailbox the messages are marked for deletion.
3890 Filename interpretation as described for the
3892 command is performed.
3909 Header fields thus marked are filtered out when saving a message by
3911 or when automatically saving to
3913 This command should only be applied to header fields that do not contain
3914 information needed to decode the message,
3915 as MIME content fields do.
3927 Header fields thus marked are the only ones saved with a message when
3930 or when automatically saving to
3935 The use of this command is strongly discouraged since it may strip
3936 header fields that are needed to decode the message correctly.
3940 Takes a message specification (list) and displays a header summary of
3941 all matching messages, as via
3943 This command is an alias of
3946 .Sx "Specifying messages" .
3950 Takes a message list and marks all messages as having been read.
3954 (se) Without arguments this command shows all variables and their
3955 values which are currently known to \*(UA.
3956 Setting any of the variables
3960 changes the output format to BSD style, otherwise a properly quoted
3961 listing is produced.
3966 has been set twice then the listing is modified to mark out assembled
3969 Otherwise modifies (set and unsets) the given variables.
3970 Arguments are of the form
3972 (no space before or after
3976 if there is no value.
3977 Quotation marks may be placed around any part of the assignment
3978 statement to quote blanks or tabs, e.g.,
3980 .Dl set indentprefix="->"
3982 If an argument begins with
3986 the effect is the same as invoking the
3988 command with the remaining part of the variable
3989 .Pf ( Ql unset save ) .
3995 except that the variables are also exported into the program environment;
3996 since this task requires native host support the command will always
3997 report error if that is not available (but still act like
4000 This operation is a no-op unless all resource files have been loaded.
4006 (sh) Invokes an interactive version of the shell.
4010 Without arguments the list of all currently defined shortcuts is
4012 Otherwise all given arguments (which need not be quoted except for
4013 whitespace) are treated as pairs of shortcuts and their expansions,
4014 creating new or changing already existing shortcuts, as necessary.
4015 Shortcuts may be removed via the command
4017 The expansion strings should be in the syntax that has been described
4026 but performs neither MIME decoding nor decryption, so that the raw
4027 message text is shown.
4031 (si) Shows the size in characters of each message of the given
4036 Shows the current sorting criterion when used without an argument.
4037 Otherwise creates a sorted representation of the current folder,
4040 command and the addressing modes such that they refer to messages in
4042 Message numbers are the same as in regular mode.
4046 a header summary in the new order is also displayed.
4047 Automatic folder sorting can be enabled by setting the
4049 variable, as in, e.g.,
4050 .Ql set autosort=thread .
4051 Possible sorting criterions are:
4053 .Bl -tag -compact -offset indent -width "subject"
4055 Sort the messages by their
4057 field, that is by the time they were sent.
4059 Sort messages by the value of their
4061 field, that is by the address of the sender.
4064 variable is set, the sender's real name (if any) is used.
4066 Sort the messages by their size.
4068 \*(OP Sort the message by their spam score, as has been classified by
4071 Sort the messages by their message status.
4073 Sort the messages by their subject.
4075 Create a threaded display.
4077 Sort messages by the value of their
4079 field, that is by the address of the recipient.
4082 variable is set, the recipient's real name (if any) is used.
4087 (so) The source command reads commands from the given file, which is
4088 subject to the usual filename expansions (see introductional words of
4090 If the given argument ends with a vertical bar
4092 then the argument will instead be interpreted as a shell command and
4093 \*(UA will read the output generated by it.
4099 (beside not supporting pipe syntax a.k.a. shell command input) is that
4100 this command will not generate an error if the given file argument
4101 cannot be opened successfully.
4102 This can matter in, e.g., resource files, since loading of those is
4103 stopped when an error is encountered.
4107 \*(OP Takes a list of messages and clears their
4113 \*(OP Takes a list of messages and causes the
4115 to forget it has ever used them to train its Bayesian filter.
4116 Unless otherwise noted the
4118 flag of the message is inspected to chose wether a message shall be
4126 \*(OP Takes a list of messages and informs the Bayesian filter of the
4130 This also clears the
4132 flag of the messages in question.
4136 \*(OP Takes a list of messages and rates them using the configured
4137 .Va spam-interface ,
4138 without modifying the messages, but setting their
4140 flag as appropriate; because the spam rating headers are lost the rate
4141 will be forgotten once the mailbox is left.
4142 Refer to the manual section
4144 for the complete picture of spam handling in \*(UA.
4148 \*(OP Takes a list of messages and sets their
4154 \*(OP Takes a list of messages and informs the Bayesian filter of the
4160 flag of the messages in question.
4169 Create a threaded representation of the current folder,
4170 i.\|e. indent messages that are replies to other messages in the header
4171 display and change the
4173 command and the addressing modes such that they refer to messages in the
4175 Message numbers are the same as in unthreaded mode.
4179 a header summary in threaded order is also displayed.
4183 (to) Takes a message list and displays the top few lines of each.
4184 The number of lines shown is controlled by the variable
4186 and defaults to five.
4190 (tou) Takes a message list and marks the messages for saving in
4192 \*(UA deviates from the POSIX standard with this command,
4195 command will display the following message instead of the current one.
4201 but also displays out ignored header fields and all parts of MIME
4202 .Ql multipart/alternative
4207 (t) Takes a message list and types out each message on the user's
4213 For MIME multipart messages, all parts with a content type of
4217 are shown, the other are hidden except for their headers.
4218 Messages are decrypted and converted to the terminal character set
4223 Delete all given accounts.
4224 An error message is shown if a given account is not defined.
4227 will discard all existing accounts.
4231 (una) Takes a list of names defined by alias commands
4232 and discards the remembered groups of users.
4235 will discard all existing aliases.
4239 Takes a message list and marks each message as not having been answered.
4243 Only applicable to threaded mode.
4244 Takes a message list and makes the message and all replies to it visible
4245 in header summaries again.
4246 When a message becomes the current message,
4247 it is automatically made visible.
4248 Also when a message with collapsed replies is displayed,
4249 all of these are automatically uncollapsed.
4255 mapping for the given colour type (see
4257 for a list of types) and mapping; if the optional precondition argument
4258 is used then only the exact tuple of mapping and precondition is removed.
4261 will remove all mappings (no precondition allowed).
4263 .Sx "Coloured display"
4264 for the general picture.
4268 Deletes the custom headers given as arguments.
4271 will remove all custom headers.
4275 Undefine all given macros.
4276 An error message is shown if a given macro is not defined.
4279 will discard all existing macros.
4283 (u) Takes a message list and marks each message as not being deleted.
4287 Takes a message list and
4293 Takes a message list and marks each message as not being
4298 Removes the header field names from the list of ignored fields for the
4303 will remove all fields.
4307 Removes the header field names from the list of retained fields for the
4312 will remove all fields.
4316 Remove all the given command
4320 will remove all ghosts.
4324 Removes the header field names from the list of ignored fields.
4327 will remove all fields.
4331 Delete all given MIME types, e.g.,
4332 .Ql unmimetype text/plain
4333 will remove all registered specifications for the MIME type
4337 will discard all existing MIME types, just as will
4339 but which also reenables cache initialization via
4340 .Va mimetypes-load-control .
4344 Forget about all the given mailing lists.
4347 will remove all lists.
4352 .It Ic unmlsubscribe
4353 Remove the subscription attribute from all given mailing lists.
4356 will clear the attribute from all lists which have it set.
4367 Takes a message list and marks each message as not having been read.
4371 Removes the header field names from the list of retained fields.
4374 will remove all fields.
4378 Removes the header field names from the list of ignored fields for
4382 will remove all fields.
4386 Removes the header field names from the list of retained fields for
4390 will remove all fields.
4394 (uns) Takes a list of option names and discards their remembered values;
4402 except that the variables are also removed from the program environment;
4403 since this task requires native host support the command will always
4404 report error if that is not available (but still act like
4407 This operation is a no-op unless all resource files have been loaded.
4413 Deletes the shortcut names given as arguments.
4416 will remove all shortcuts.
4420 Disable sorted or threaded mode
4426 return to normal message order and,
4430 displays a header summary.
4440 Decode the given URL-encoded string arguments and show the results.
4441 Note the resulting strings may not be valid in the current locale, see
4446 URL-encode the given arguments and show the results.
4447 Because the arguments effectively are in the character set of the
4448 current locale the results will vary accordingly unless the input solely
4449 consists of characters in the portable character set, see
4450 .Sx "Character sets" .
4454 Edit the values of or create the given variable(s) in the
4456 Boolean variables cannot be edited.
4460 Show informations about all the given variables.
4461 \*(UA knows about a finite set of known builtin variables that are
4462 subdivided further in boolean and value variants;
4463 they may have special properties, like
4465 (setting may not be changed) and
4467 meaning that the value is generated on-the-fly as necessary.
4468 Beside those known variables an infinite number of unknown, so-called
4470 variables, which are expected to be able to store values, may exist.
4471 .Bd -literal -offset indent
4473 ? varshow sendwait version-major foo bar
4474 "sendwait": (73) boolean: set=1 (ENVIRON=0)
4475 "version-major": (192) value, read-only, virtual:\e
4476 set=1 (ENVIRON=0) value<14>
4477 "foo": (assembled) set=1 (ENVIRON=0) value<bar>
4478 "bar": (assembled) set=0 (ENVIRON=0) value<NULL>
4483 \*(OP Takes a message list and verifies each message.
4484 If a message is not a S/MIME signed message,
4485 verification will fail for it.
4486 The verification process checks if the message was signed using a valid
4488 if the message sender's email address matches one of those contained
4489 within the certificate,
4490 and if the message content has been altered.
4494 (v) Takes a message list and invokes the display editor on each message.
4495 Modified contents are discarded unless the
4501 (w) For conventional messages the body without all headers is written.
4502 The output is decrypted and converted to its native format as necessary.
4503 If the output file exists, the text is appended.
4504 If a message is in MIME multipart format its first part is written to
4505 the specified file as for conventional messages,
4506 and the user is asked for a filename to save each other part.
4507 For convience saving of each part may be skipped by giving an empty value;
4508 the same result can also be achieved by writing it to
4510 For the second and subsequent parts a leading
4512 character causes the part to be piped to the remainder of the user input
4513 interpreted as a shell command;
4514 otherwise the user input is expanded as usually for folders,
4515 e.g., tilde expansion is performed.
4516 In non-interactive mode, only the parts of the multipart message
4517 that have a filename given in the part header are written,
4518 the others are discarded.
4519 The original message is never marked for deletion in the originating
4522 the contents of the destination file are overwritten if the file
4524 No special handling of compressed files is performed.
4533 \*(UA presents message headers in windowfuls as described under the
4536 This command scrolls to the next window of messages.
4537 If an argument is given,
4538 it specifies the window to use.
4539 A number prefixed by
4543 indicates that the window is calculated in relation to the current position.
4544 A number without a prefix specifies an absolute window number,
4547 lets \*(UA scroll to the last window of messages.
4553 but scrolls to the next or previous window that contains at least one
4562 .\" .Sh TILDE ESCAPES {{{
4565 Here is a summary of the tilde escapes,
4566 which are used to perform special functions when composing messages.
4567 Tilde escapes are only recognized at the beginning of lines.
4570 is somewhat of a misnomer since the actual escape character can be
4571 changed by adjusting the option
4574 .Bl -tag -width ".Ic __ filename"
4577 Insert the string of text in the message prefaced by a single
4579 (If the escape character has been changed,
4580 that character must be doubled
4581 in order to send it at the beginning of a line.)
4584 .It Ic ~! Ar command
4585 Execute the indicated shell
4587 then return to the message.
4591 Same effect as typing the end-of-file character.
4594 .It Ic ~: Ar \*(UA-command Ns \0or Ic ~_ Ar \*(UA-command
4595 Execute the given \*(UA command.
4596 Not all commands, however, are allowed.
4600 Write a summary of command escapes.
4603 .It Ic ~< Ar filename
4608 .It Ic ~<! Ar command
4610 is executed using the shell.
4611 Its standard output is inserted into the message.
4614 .It Ic ~@ Op Ar filename...
4615 With no arguments, edit the attachment list interactively.
4616 If an attachment's file name is left empty,
4617 that attachment is deleted from the list.
4618 When the end of the attachment list is reached,
4619 \*(UA will ask for further attachments until an empty name is given.
4620 If a given file name solely consists of the number sign
4622 followed by a valid message number of the currently active mailbox, then
4623 the given message is attached as a MIME
4625 and the rest of this section does not apply.
4627 If character set conversion has been compiled into \*(UA, then this mode
4628 gives the user the option to specify input and output character sets,
4629 unless the file extension indicates binary content, in which case \*(UA
4630 asks wether this step shall be skipped for the attachment in question.
4631 If not skipped, then the charset that succeeds to represent the
4632 attachment data will be used in the
4634 MIME parameter of the mail message:
4636 .Bl -bullet -compact
4638 If input and output character sets are specified, then the conversion is
4639 performed on the fly.
4640 The user will be asked repeatedly until the desired conversion succeeds.
4642 If only an output character set is specified, then the input is assumed
4645 charset and will be converted to the given output charset on the fly.
4646 The user will be asked repeatedly until the desired conversion succeeds.
4648 If no character sets are specified at all then the algorithm that is
4649 documented in the section
4650 .Sx "Character sets"
4651 is applied, but directly and on the fly.
4652 The user will be asked repeatedly until the desired conversion succeeds.
4654 Finally, if an input-, but no output character set is specified, then no
4655 conversion is ever performed, but the
4657 MIME parameter value will still be set to the user input.
4659 The character set selection loop can be left by typing
4661 i.e., causing an interrupt.
4662 .\" \*(OU next sentence
4663 Note that before \*(UA version 15.0 this terminates the entire
4664 current attachment selection, not only the character set selection.
4667 Without character set conversion support, \*(UA will ask for the input
4668 character set only, and it'll set the
4670 MIME parameter value to the given input, if any;
4671 if no user input is seen then the
4673 character set will be used for the parameter value instead.
4674 Note that the file extension check isn't performed in this mode, since
4675 no conversion will take place anyway.
4677 Note that in non-interactive mode, for reproduceabilities sake, there
4678 will always be two questions for each attachment, regardless of wether
4679 character set conversion is available and what the file extension is.
4680 The first asks for the filename, and the second asks for the input
4681 character set to be passed through to the corresponding MIME parameter;
4682 no conversion will be tried if there is input to the latter question,
4683 otherwise the usual conversion algorithm, as above, is applied.
4684 For message attachments, the answer to the second question is completely
4689 arguments are specified for the
4691 command they are treated as a comma-separated list of files,
4692 which are all expanded and appended to the end of the attachment list.
4693 (Commas need to be escaped with backslash, but filenames with leading or
4694 trailing whitespace can only be added via the command line or the first
4696 Message attachments can only be added via the first method;
4697 filenames which clash with message numbers can only be added via the
4698 command line or the second method.)
4699 In this mode the (text) attachments are assumed to be in
4701 encoding, and will be evaluated as documented in the section
4702 .Sx "Character sets" .
4706 Inserts the string contained in the
4709 .Ql Ic ~i Ns \0Sign ) .
4710 The escape sequences tabulator
4718 Inserts the string contained in the
4721 .Ql Ic ~i Ns \0sign ) .
4722 The escape sequences tabulator
4729 .It Ic ~b Ar name ...
4730 Add the given names to the list of blind carbon copy recipients.
4733 .It Ic ~c Ar name ...
4734 Add the given names to the list of carbon copy recipients.
4738 Read the file specified by the
4740 variable into the message.
4744 Invoke the text editor on the message collected so far.
4745 After the editing session is finished,
4746 the user may continue appending text to the message.
4749 .It Ic ~F Ar messages
4750 Read the named messages into the message being sent, including all
4751 message headers and MIME parts.
4752 If no messages are specified, read in the current message.
4755 .It Ic ~f Ar messages
4756 Read the named messages into the message being sent.
4757 If no messages are specified, read in the current message.
4761 lists are used to modify the message headers.
4762 For MIME multipart messages,
4763 only the first displayable part is included.
4767 Edit the message header fields
4772 by typing each one in turn and allowing the user to edit the field.
4773 The default values for these fields originate from the
4781 Edit the message header fields
4787 by typing each one in turn and allowing the user to edit the field.
4790 .It Ic ~i Ar variable
4791 Insert the value of the specified variable into the message,
4792 adding a newline character at the end.
4793 The message remains unaltered if the variable is unset or empty.
4794 The escape sequences tabulator
4801 .It Ic ~M Ar messages
4802 Read the named messages into the message being sent,
4805 If no messages are specified, read the current message.
4808 .It Ic ~m Ar messages
4809 Read the named messages into the message being sent,
4812 If no messages are specified, read the current message.
4816 lists are used to modify the message headers.
4817 For MIME multipart messages,
4818 only the first displayable part is included.
4822 Display the message collected so far,
4823 prefaced by the message header fields
4824 and followed by the attachment list, if any.
4828 Abort the message being sent,
4829 copying it to the file specified by the
4836 .It Ic ~R Ar filename
4837 Read the named file into the message, indented by
4841 .It Ic ~r Ar filename
4842 Read the named file into the message.
4846 Cause the named string to become the current subject field.
4849 .It Ic ~t Ar name ...
4850 Add the given name(s) to the direct recipient list.
4853 .It Ic ~U Ar messages
4854 Read in the given / current message(s) excluding all headers, indented by
4858 .It Ic ~u Ar messages
4859 Read in the given / current message(s), excluding all headers.
4863 Invoke an alternate editor (defined by the
4865 option) on the message collected so far.
4866 Usually, the alternate editor will be a screen editor.
4867 After the editor is quit,
4868 the user may resume appending text to the end of the message.
4871 .It Ic ~w Ar filename
4872 Write the message onto the named file.
4874 the message is appended to it.
4880 except that the message is not saved at all.
4883 .It Ic ~| Ar command
4884 Pipe the message through the specified filter command.
4885 If the command gives no output or terminates abnormally,
4886 retain the original text of the message.
4889 is often used as a rejustifying filter.
4894 .\" .Sh INTERNAL VARIABLES {{{
4895 .Sh "INTERNAL VARIABLES"
4897 Internal \*(UA variables are controlled via the
4901 commands; prefixing a variable name with the string
4905 has the same effect as using
4911 Creation or editing of variables can be performed in the
4916 will give more insight on the given variable(s), and
4918 when called without arguments, will show a listing of all variables.
4919 Variables are also implicitly inherited from the program
4921 and can be set explicitly via the command line option
4925 Two different kind of variables exist.
4926 There are boolean variables, which can only be in one of the two states
4930 and value variables with a(n optional) string value.
4931 For the latter proper quoting is necessary upon assignment time:
4932 To embed whitespace (space and tabulator) in a value it either needs to
4933 be escaped with a backslash character, or the entire value must be
4934 enclosed in (double or single) quotation marks;
4935 To use quotation marks identical to those used to enclose the value,
4936 escape them with a backslash character.
4937 The backslash character has no special meaning except in these cases.
4939 .Bd -literal -offset indent
4940 set one=val\e 1 two="val 2" \e
4941 three='val "3"' four='val \e'4\e''
4942 varshow one two three four
4943 unset one two three four
4947 Dependent upon the actual option the string values will be interpreted
4948 as numbers, colour names, normal text etc., but there also exists
4949 a special kind of string value, the
4950 .Dq boolean string ,
4951 which must either be a decimal integer (in which case
4955 and any other value is true) or any of the (case-insensitive) strings
4960 for a false boolean and
4965 for a true boolean; a special kind of boolean string is the
4967 which is a boolean string that can optionally be prefixed with the
4968 (case-insensitive) term
4972 which causes prompting of the user in interactive mode, with the given
4973 boolean as the default value.
4975 .\" .Ss "Initial settings" {{{
4976 .\" (Keep in SYNC: ./main.c:_startup(), ./nail.rc, ./nail.1:"Initial settings"!)
4977 .Ss "Initial Settings"
4979 The standard POSIX 2008/Cor 1-2013 mandates the following initial
4985 .Pf no Va autoprint ,
4999 .Pf no Va ignoreeof ,
5001 .Pf no Va keepsave ,
5003 .Pf no Va outfolder ,
5008 (note that \*(UA deviates from the standard by using
5012 special prompt escape results in
5020 .Pf no Va sendwait ,
5029 Notes: \*(UA doesn't support the
5031 variable \(en use command line options or
5032 .Va sendmail-arguments
5033 to pass options through to a MTA.
5034 And the default global
5036 file (which is loaded unless the
5038 command line flag has been used or the
5039 .Ev NAIL_NO_SYSTEM_RC
5040 environment variable is set) bends those initial settings a bit, e.g.,
5041 it sets the variables
5046 to name a few, calls
5048 etc., and should thus be taken into account.
5051 .\" .Ss "Variables" {{{
5054 .Bl -tag -width ".It Va _utoprin_"
5056 .It Va add-file-recipients
5057 \*(BO When file or pipe recipients have been specified,
5058 mention them in the corresponding address fields of the message instead
5059 of silently stripping them from their recipient list.
5060 By default such addressees are not mentioned.
5062 .Mx Va agent-shell-lookup
5063 .It Va agent-shell-lookup-USER@HOST , agent-shell-lookup-HOST , \
5065 \*(IN\*(OP Account passwords can be fetched via an external agent
5066 program in order to permit encrypted password storage \(en see
5067 .Sx "On URL syntax and credential lookup"
5068 for more on credential lookup.
5069 If this is set then the content is interpreted as a shell command the
5070 output of which (with newline characters removed) is treated as the
5071 account password shall the command succeed (and have produced non-empty
5072 non-newline output); e.g., via
5074 .Bd -literal -offset indent
5075 $ echo PASSWORD > .pass
5077 $ eval `gpg-agent --daemon \e
5078 --pinentry-program=/usr/bin/pinentry-curses \e
5079 --max-cache-ttl 99999 --default-cache-ttl 99999`
5080 $ echo 'set agent-shell-lookup="gpg -d .pass.gpg"' \e
5084 A couple of environment variables will be set for the agent:
5086 .Bl -tag -compact -width ".It Ev _AIL_TMPDIR[337]"
5088 The temporary directory that \*(UA uses.
5089 Usually identical to
5091 but guaranteed to be set and usable by child processes;
5092 to ensure the latter condition for
5098 for which the password is looked up.
5099 .It Ev NAIL_USER_ENC
5100 The URL percent-encoded variant of
5103 The plain machine hostname of the user account.
5104 .It Ev NAIL_HOST_PORT
5107 (hostname possibly including port) of the user account.
5112 \*(BO Causes only the local part to be evaluated
5113 when comparing addresses.
5117 \*(BO Causes messages saved in
5119 to be appended to the end rather than prepended.
5120 This should always be set.
5124 \*(BO Causes \*(UA to prompt for the subject of each message sent.
5125 If the user responds with simply a newline,
5126 no subject field will be sent.
5130 \*(BO Causes the prompts for
5134 lists to appear after the message has been edited.
5138 \*(BO If set, \*(UA asks for files to attach at the end of each message,
5139 shall the list be found empty at that time.
5140 An empty line finalizes the list.
5144 \*(BO Causes the user to be prompted for carbon copy recipients
5145 (at the end of each message if
5149 are set) shall the list be found empty (at that time).
5150 An empty line finalizes the list.
5154 \*(BO Causes the user to be prompted for blind carbon copy
5155 recipients (at the end of each message if
5159 are set) shall the list be found empty (at that time).
5160 An empty line finalizes the list.
5164 \*(BO\*(OP Causes the user to be prompted if the message is to be
5165 signed at the end of each message.
5168 variable is ignored when this variable is set.
5172 \*(BO Alternative name for
5179 .It Va attachment-ask-content-description , \
5180 attachment-ask-content-disposition , \
5181 attachment-ask-content-id , \
5182 attachment-ask-content-type
5183 \*(BO If set then the user will be prompted for some attachment
5184 information when editing the attachment list.
5185 It is advisable to not use these but for the first of the variables;
5186 even for that it has to be noted that the data is used
5192 A sequence of characters to display in the
5196 as shown in the display of
5198 each for one type of messages (see
5199 .Sx "Message states" ) ,
5200 with the default being
5203 .Ql NU\ \ *HMFAT+\-$~
5206 variable is set, in the following order:
5208 .Bl -tag -compact -offset indent -width ".It Ql _"
5230 start of a collapsed thread.
5232 an uncollapsed thread (TODO ignored for now).
5236 classified as possible spam.
5242 Specifies a list of recipients to which a blind carbon copy of each
5243 outgoing message will be sent automatically.
5247 Specifies a list of recipients to which a carbon copy of each outgoing
5248 message will be sent automatically.
5252 \*(BO Causes threads to be collapsed automatically when threaded mode
5259 \*(BO Causes the delete command to behave like
5261 thus, after deleting a message the next one will be typed automatically.
5265 \*(BO\*(OB Causes threaded mode (see the
5267 command) to be entered automatically when a folder is opened.
5269 .Ql autosort=thread .
5273 Causes sorted mode (see the
5275 command) to be entered automatically with the value of this option as
5276 sorting method when a folder is opened, e.g.,
5277 .Ql set autosort=thread .
5281 \*(BO Enables the substitution of
5283 by the contents of the last command line in shell escapes.
5286 .It Va batch-exit-on-error
5287 \*(BO If the batch mode has been enabled via the
5289 command line option, then this variable will be consulted whenever \*(UA
5290 completes one operation (returns to the command prompt); if it is set
5291 then \*(UA will terminate if the last operation generated an error.
5295 \*(BO Causes automatic display of a header summary after executing a
5301 \*(BO Sets some cosmetical features to traditional BSD style;
5302 has the same affect as setting
5304 and all other variables prefixed with
5306 it also changes the meaning of the \*(UA specific
5309 escape sequence and changes behaviour of
5311 (which doesn't exist in BSD).
5315 \*(BO Changes the letters shown in the first column of a header
5316 summary to traditional BSD style.
5320 \*(BO Changes the display of columns in a header summary to traditional
5325 \*(BO Changes some informational messages to traditional BSD style.
5331 field to appear immediately after the
5333 field in message headers and with the
5335 .Sx "TILDE ESCAPES" .
5339 \*(BO Changes the output format of the
5341 command to traditional BSD style.
5345 The value that should appear in the
5349 MIME header fields when no character set conversion of the message data
5351 This defaults to US-ASCII, and the chosen character set should be
5352 US-ASCII compatible.
5356 \*(OP The default 8-bit character set that is used as an implicit last
5357 member of the variable
5359 This defaults to UTF-8.
5360 If no character set conversion capabilities are available in \*(UA then
5361 the only supported character set is
5363 Refer to the section
5364 .Sx "Character sets"
5365 for the complete picture of character set conversion in \*(UA.
5368 .It Va charset-unknown-8bit
5369 \*(OP RFC 1428 specifies conditions when internet mail gateways shall
5371 the content of a mail message by using a character set with the name
5373 Because of the unclassified nature of this character set \*(UA will not
5374 be capable to convert this character set to any other character set.
5375 If this variable is set any message part which uses the character set
5377 is assumed to really be in the character set given in the value,
5378 otherwise the (final) value of
5380 is used for this purpose.
5384 The default value for the
5389 .It Va colour-disable
5390 \*(BO\*(OP Forcefully disable usage of colours.
5391 Also see the section
5392 .Sx "Coloured display" .
5396 \*(BO\*(OP Wether colour shall be used for output that is paged through
5398 Note that pagers may need special flags, e.g.,
5406 in order to support colours; therefore \*(UA will inspect the variable
5408 \(en if that starts with the string
5410 a non-existing environment variable
5417 will optionally be set to
5419 Also see the section
5420 .Sx "Coloured display"
5425 \*(OP A comma-separated list of
5427 inals for which coloured display can be used.
5428 Entries only need to be added if the string
5430 isn't part of the terminal name itself; the default value is
5432 .\" (Keep in SYNC: ./nail.h:n_COLOUR_TERMS, ./nail.1:*colour-terms*"!)
5433 .Dl aterm,cons25,gnome,konsole,\:kterm,\:linux,\:\
5434 rxvt,\:rxvt-unicode,\:screen,\:sun,\:vt100,\:vt220,\:wsvt25,\:xterm
5438 In a(n interactive) terminal session, then if this valued option is set
5439 it'll be used as a threshold to determine how many lines the given
5440 output has to span before it will be displayed via the configured
5444 can be forced by setting this to the value
5446 setting it without a value will deduce the current height of the
5447 terminal screen to compute the treshold (see
5455 \*(OB A variable counterpart of the
5457 command (see there for documentation), interpreted as a comma-separated
5458 list of custom headers to be injected, to include commas in the header
5459 bodies escape them with backslash, e.g.:
5461 .Dl set customhdr="Hdr1: Body1-1\e, Body1-2, Hdr2: Body2"
5467 the message date, if any is to be displayed according to the format of
5469 is by default taken from the
5471 line of the message.
5472 If this variable is set the date as given in the
5474 header field is used instead, converted to local time.
5475 To control the display format of the date assign a valid
5480 format should not be used, because \*(UA doesn't take embedded newlines
5481 into account when calculating how many lines fit onto the screen.)
5483 .Va datefield-markout-older .
5486 .It Va datefield-markout-older
5487 This option, when set in addition to
5491 messages (concept is rather comparable to the
5493 option of the POSIX utility
5495 The content interpretation is identical to
5500 \*(BO Enables debug messages and obsoletion warnings, disables the
5501 actual delivery of messages and also implies
5507 .It Va disposition-notification-send
5509 .Ql Disposition-Notification-To:
5510 header (RFC 3798) with the message.
5514 .\" TODO .It Va disposition-notification-send-HOST
5516 .\".Va disposition-notification-send
5517 .\" for SMTP accounts on a specific host.
5518 .\" TODO .It Va disposition-notification-send-USER@HOST
5520 .\".Va disposition-notification-send
5521 .\"for a specific account.
5525 \*(BO When dot is set, a period
5527 on a line by itself during message input in (interactive) compose mode
5528 will be treated as end-of-message (in addition to the normal end-of-file
5537 .It Va dotlock-ignore-error
5538 \*(BO\*(OP Synchronization of mailboxes which \*(UA treats as system
5539 mailboxes (see the command
5541 will be protected with so-called dotlock files\(emthe traditional mail
5542 spool file locking method\(emin addition to system file locking.
5543 Because \*(UA ships with a privilege-separated dotlock creation program
5544 that should always be able to create such a dotlock file there is no
5545 good reason to ignore dotlock file creation errors, and thus these are
5546 fatal unless this variable is set.
5550 \*(BO If this variable is set then the editor is started automatically
5551 when a message is composed in interactive mode, as if the
5557 variable is implied for this automatically spawned editor session.
5561 \*(BO When a message is edited while being composed,
5562 its header is included in the editable text.
5572 fields are accepted within the header, other fields are ignored.
5576 \*(BO When entering interactive mode \*(UA normally writes
5577 .Dq \&No mail for user
5578 and exits immediately if a mailbox is empty or doesn't exist.
5579 If this option is set \*(UA starts even with an empty or nonexistent
5580 mailbox (the latter behaviour furtherly depends upon
5586 Suggestion for the MIME encoding to use in outgoing text messages
5588 Valid values are the default
5589 .Ql quoted-printable ,
5594 may cause problems when transferring mail messages over channels that
5595 are not ESMTP (RFC 1869) compliant.
5596 If there is no need to encode a message,
5598 transfer mode is always used regardless of this variable.
5599 Binary data is always encoded as
5604 If defined, the first character of this option
5605 gives the character to use in place of
5608 .Sx "TILDE ESCAPES" .
5612 If not set then file and command pipeline targets are not allowed,
5613 and any such address will be filtered out, giving a warning message.
5614 If set without a value then all possible recipient address
5615 specifications will be accepted \(en see the section
5616 .Sx "On sending mail, and non-interactive mode"
5618 To accept them, but only in interactive mode, or when tilde commands
5619 were enabled explicitly by using one of the command line options
5623 set this to the (case-insensitive) value
5625 (note right now this is actually like setting
5626 .Ql restrict,-all,+name,+addr ) .
5628 In fact the value is interpreted as a comma-separated list of values.
5631 then the existence of disallowed specifications is treated as a hard
5632 send error instead of only filtering them out.
5633 The remaining values specify wether a specific type of recipient
5634 address specification is allowed (optionally indicated by a plus sign
5636 prefix) or disallowed (prefixed with a hyphen
5640 addresses all possible address specifications,
5644 command pipeline targets,
5646 plain user names and (MTA) aliases (\*(OB
5648 may be used as an alternative syntax to
5653 These kind of values are interpreted in the given order, so that
5654 .Ql restrict,\:fail,\:+file,\:-all,\:+addr
5655 will cause hard errors for any non-network address recipient address
5656 unless \*(UA is in interactive mode or has been started with the
5660 command line option; in the latter case(s) any address may be used, then.
5664 Unless this variable is set additional mail-transfer-agent (MTA)
5665 arguments from the command line, as can be given after a
5667 separator, are ignored due to safety reasons.
5668 However, if set to the special (case-insensitive) value
5670 then the presence of additional MTA arguments is treated as a hard
5671 error that causes \*(UA to exit with failure status.
5672 A lesser strict variant is the otherwise identical
5674 which does accept such arguments in interactive mode, or if tilde
5675 commands were enabled explicitly by using one of the command line options
5682 \*(RO Information on the features compiled into \*(UA \(en the content
5683 of this variable is identical to the output of the command
5688 \*(BO This option reverses the meanings of a set of reply commands,
5689 turning the lowercase variants, which by default address all recipients
5690 included in the header of a message
5691 .Pf ( Ic reply , respond , followup )
5692 into the uppercase variants, which by default address the sender only
5693 .Pf ( Ic Reply , Respond , Followup )
5696 .Ic replysender , respondsender , followupsender
5698 .Ic replyall , respondall , followupall
5699 are not affected by the current setting of
5704 .It Va file-hook-load-EXTENSION , file-hook-save-EXTENSION
5705 It is possible to install file hooks which will be used by the
5707 command in order to be able to transparently handle (through an
5708 intermediate temporary file) files with specific
5710 s: the variable values can include shell snippets and are expected to
5711 write data to standard output / read data from standard input,
5713 \*(ID The variables may not be changed while there is a mailbox
5715 .Bd -literal -offset indent
5716 set file-hook-load-xy='echo >&2 XY-LOAD; gzip -cd' \e
5717 file-hook-save-xy='echo >&2 XY-SAVE; gzip -c' \e
5718 record=+null-sent.xy
5723 The name of the directory to use for storing folders of messages.
5724 All folder names that begin with
5726 refer to files below it.
5727 The same special conventions as documented for the
5729 command may be used when specifying a new value for
5731 but be aware that the expansion is fully performed immediately.
5735 This variable can be set to the name of a
5737 macro which will be called whenever a
5740 The macro will also be invoked when new mail arrives,
5741 but message lists for commands executed from the macro
5742 only include newly arrived messages then.
5745 are activated in a folder hook, then the covered settings will be
5746 reverted once the folder is left again.
5747 .Bd -filled -offset indent
5749 Macro behaviour, including option localization, will change in v15.
5750 To be on the absolutely safe side and avoid any surprises it may be wise
5751 to use wrappers that depend on the program version, e.g.,:
5753 .Bd -literal -offset indent
5754 if $version-major < 15
5760 echo "Please re-verify sent-hook (post v15)"
5763 folder-hook-+sent=sent-hook
5767 .It Va folder-hook-FOLDER
5772 Unlike other folder specifications, the fully expanded name of a folder,
5773 without metacharacters, is used to avoid ambiguities.
5774 However, if the mailbox resides under
5778 specification is tried in addition, e.g., if
5782 (and thus relative to the user's home directory) then
5783 .Pa /home/usr1/mail/sent
5785 .Ql folder-hook-/home/usr1/mail/sent
5786 first, but then followed by
5787 .Ql folder-hook-+sent .
5791 \*(BO Controls wether a
5792 .Ql Mail-Followup-To:
5793 header is generated when sending messages to known mailing lists.
5795 .Va followup-to-honour
5797 .Ic mlist , mlsubscribe , reply
5802 .It Va followup-to-honour
5804 .Ql Mail-Followup-To:
5805 header is honoured when group-replying to a message via
5809 This is a quadoption; if set without a value it defaults to
5819 .It Va forward-as-attachment
5820 \*(BO Original messages are normally sent as inline text with the
5823 and only the first part of a multipart message is included.
5824 With this option messages are sent as unmodified MIME
5826 attachments with all of their parts included.
5830 The address (or a list of addresses) to put into the
5832 field of the message header, quoting RFC 5322:
5833 the author(s) of the message, that is, the mailbox(es) of the person(s)
5834 or system(s) responsible for the writing of the message.
5835 If replying to messages these addresses are handled as if they were in
5839 If the machine's hostname is not valid at the Internet (for example at
5840 a dialup machine) then either this variable or
5845 adds even more fine-tuning capabilities),
5849 contains more than one address,
5852 variable is required (according to the standard RFC 5322).
5856 \*(BO When replying to or forwarding a message \*(UA normally removes
5857 the comment and name parts of email addresses.
5858 If this variable is set such stripping is not performed,
5859 and comments, names etc. are retained.
5863 The string to put before the text of a message with the
5867 .Va forward-as-attachment
5870 .Dq -------- Original Message --------
5871 if unset; No heading is put if it is set to the empty string.
5875 \*(BO Causes the header summary to be written at startup and after
5876 commands that affect the number of messages or the order of messages in
5877 the current folder; enabled by default.
5878 The command line option
5886 A format string to use for the summary of
5888 similar to the ones used for
5891 Format specifiers in the given string start with a percent character
5893 and may be followed by an optional decimal number indicating the field
5894 width \(em if that is negative, the field is to be left-aligned.
5895 Valid format specifiers are:
5898 .Bl -tag -compact -offset indent -width "_%%_"
5900 A plain percent character.
5903 a space character but for the current message
5905 for which it expands to
5909 a space character but for the current message
5911 for which it expands to
5914 \*(OP The spam score of the message, as has been classified via the
5917 Shows only a replacement character if there is no spam support.
5919 Message attribute character (status flag); the actual content can be
5923 The date when the message was received, or the date found in the
5927 variable is set (optionally to a date display format string).
5929 The indenting level in threaded mode.
5931 The address of the message sender.
5933 The message thread tree structure.
5934 (Note that this format doesn't support a field width.)
5936 The number of lines of the message, if available.
5940 The number of octets (bytes) in the message, if available.
5942 Message subject (if any).
5944 Message subject (if any) in double quotes.
5946 Message recipient flags: is the addressee of the message a known or
5947 subscribed mailing list \(en see
5952 The position in threaded/sorted order.
5956 .Ql %>\&%a\&%m\ %-18f\ %16d\ %4l/%\-5o\ %i%-s ,
5958 .Ql %>\&%a\&%m\ %20-f\ \ %16d\ %3l/%\-5o\ %i%-S
5969 .It Va headline-bidi
5970 Bidirectional text requires special treatment when displaying headers,
5971 because numbers (in dates or for file sizes etc.) will not affect the
5972 current text direction, in effect resulting in ugly line layouts when
5973 arabic or other right-to-left text is to be displayed.
5974 On the other hand only a minority of terminals is capable to correctly
5975 handle direction changes, so that user interaction is necessary for
5977 Note that extended host system support is required nonetheless, e.g.,
5978 detection of the terminal character set is one precondition;
5979 and this feature only works in an Unicode (i.e., UTF-8) locale.
5981 In general setting this variable will cause \*(UA to encapsulate text
5982 fields that may occur when displaying
5984 (and some other fields, like dynamic expansions in
5986 with special Unicode control sequences;
5987 it is possible to fine-tune the terminal support level by assigning
5989 no value (or any value other than
5994 will make \*(UA assume that the terminal is capable to properly deal
5995 with Unicode version 6.3, in which case text is embedded in a pair of
5996 U+2068 (FIRST STRONG ISOLATE) and U+2069 (POP DIRECTIONAL ISOLATE)
5998 In addition no space on the line is reserved for these characters.
6000 Weaker support is chosen by using the value
6002 (Unicode 6.3, but reserve the room of two spaces for writing the control
6003 sequences onto the line).
6008 select Unicode 1.1 support (U+200E, LEFT-TO-RIGHT MARK); the latter
6009 again reserves room for two spaces in addition.
6013 \*(OP If a command line editor is available then this can be set to
6014 name the (expandable) path of the location of a permanent history file.
6017 .It Va history-gabby
6018 \*(BO\*(OP Add more entries to the history as is normally done.
6021 .It Va history-gabby-persist
6022 \*(BO\*(OP \*(UA's own MLE will not save the additional
6024 entries in persistent storage unless this variable is set.
6025 On the other hand it will not loose the knowledge of wether a persistent
6026 entry was gabby or not.
6032 \*(OP If a command line editor is available this value restricts the
6033 amount of history entries that are saved into a set and valid
6035 A value of less than 0 disables this feature;
6036 note that loading and incorporation of
6038 upon program startup can also be suppressed by doing this.
6039 An unset or invalid value, or 0, causes a default value to be used.
6040 Dependent on the available command line editor this will also define the
6041 number of history entries in memory;
6042 it is also editor-specific wether runtime updates of this value will be
6047 \*(BO This option is used to hold messages in the system mailbox,
6048 and it is set by default.
6052 Use this string as hostname when expanding local addresses instead of
6053 the value obtained from
6064 transport is not used then it is normally the responsibility of the MTA
6065 to create these fields, \*(IN in conjunction with
6069 also influences the results;
6070 you should produce some test messages with the desired combination of
6079 \*(BO\*(OP Can be used to turn off the automatic conversion of domain
6080 names according to the rules of IDNA (internationalized domain names
6082 Since the IDNA code assumes that domain names are specified with the
6084 character set, an UTF-8 locale charset is required to represent all
6085 possible international domain names (before conversion, that is).
6089 \*(BO Ignore interrupt signals from the terminal while entering
6090 messages; instead echo them as
6092 characters and discard the current line.
6096 \*(BO Ignore end-of-file conditions
6097 .Pf ( Ql control-D )
6098 in compose mode on message input and in interactive command input.
6099 If set an interactive command input session can only be left by
6100 explicitly using one of the commands
6104 and message input in compose mode can only be terminated by entering
6107 on a line by itself or by using the
6109 .Sx "TILDE ESCAPES" ;
6111 overrides a setting of
6123 option for indenting messages,
6124 in place of the normal tabulator character
6126 which is the default.
6127 Be sure to quote the value if it contains spaces or tabs.
6131 \*(BO If set, an empty mailbox file is not removed.
6132 This may improve the interoperability with other mail user agents
6133 when using a common folder directory, and prevents malicious users
6134 from creating fake mailboxes in a world-writable spool directory.
6135 Note this only applies to local regular (MBOX) files, other mailbox
6136 types will never be removed.
6139 .It Va keep-content-length
6140 \*(BO When (editing messages and) writing
6142 mailbox files \*(UA can be told to keep the
6146 header fields that some MUAs generate by setting this variable.
6147 Since \*(UA does neither use nor update these non-standardized header
6148 fields (which in itself shows one of their conceptual problems),
6149 stripping them should increase interoperability in between MUAs that
6150 work with with same mailbox files.
6151 Note that, if this is not set but
6152 .Va writebackedited ,
6153 as below, is, a possibly performed automatic stripping of these header
6154 fields already marks the message as being modified.
6158 \*(BO When a message is saved it is usually discarded from the
6159 originating folder when \*(UA is quit.
6160 Setting this option causes all saved message to be retained.
6163 .It Va line-editor-cursor-right
6164 \*(OP If the builtin command line editor is used, actions which are
6165 based on rightwise movement may not work on some terminals.
6166 If you encounter such problems, set this variable to the terminal
6167 control sequence that is necessary to move the cursor one column to the
6171 which should work for most terminals.
6178 and other control character have to be written as shell-style escape
6185 .It Va line-editor-disable
6186 \*(BO Turn off any enhanced line editing capabilities (see
6187 .Sx "Command line editor"
6192 \*(BO When a message is replied to and this variable is set,
6193 it is marked as having been answered.
6194 This mark has no technical meaning in the mail system;
6195 it just causes messages to be marked in the header summary,
6196 and makes them specially addressable.
6200 \*(BO \*(UA generates and expects fully RFC 4155 compliant MBOX text
6202 Messages which are fetched over the network or from within already
6203 existing Maildir (or any non-MBOX) mailboxes may require so-called
6205 quoting (insertion of additional
6207 characters to prevent line content misinterpretation) to be applied in
6208 order to be storable in MBOX mailboxes, however, dependent on the
6209 circumspection of the message producer.
6210 (E.g., \*(UA itself will, when newly generating messages, choose a
6211 .Pf Content-Transfer- Va encoding
6212 that prevents the necessity for such quoting \(en a necessary
6213 precondition to ensure message checksums won't change.)
6215 By default \*(UA will perform this
6217 quoting in a way that results in a MBOX file that is compatible with
6218 the POSIX MBOX layout, which means that, in order not to exceed the
6219 capabilities of simple applications, many more
6221 lines get quoted (thus modified) than necessary according to RFC 4155.
6222 Set this option to instead generate MBOX files which comply to RFC 4155.
6226 \*(BO Internal development variable.
6229 .It Va message-id-disable
6230 \*(BO By setting this option the generation of
6232 can be completely suppressed, effectively leaving this task up to the
6233 mail-transfer-agent (MTA) or the SMTP server.
6234 (According to RFC 5321 your SMTP server is not required to add this
6235 field by itself, so you should ensure that it accepts messages without a
6239 .It Va message-inject-head
6240 A string to put at the beginning of each new message.
6241 The escape sequences tabulator
6248 .It Va message-inject-tail
6249 A string to put at the end of each new message.
6250 The escape sequences tabulator
6258 \*(BO Usually, when an
6260 expansion contains the sender, the sender is removed from the expansion.
6261 Setting this option suppresses these removals.
6266 option to be passed to mail-transfer-agents (MTAs);
6267 though most of the modern MTAs don't (no longer) document this flag, no
6268 MTA is known which doesn't support it (for historical compatibility).
6271 .It Va mime-allow-text-controls
6272 \*(BO When sending messages, each part of the message is MIME-inspected
6273 in order to classify the
6276 .Ql Content-Transfer-Encoding:
6279 that is required to send this part over mail transport, i.e.,
6280 a computation rather similar to what the
6282 command produces when used with the
6286 This classification however treats text files which are encoded in
6287 UTF-16 (seen for HTML files) and similar character sets as binary
6288 octet-streams, forcefully changing any
6293 .Ql application/octet-stream :
6294 If that actually happens a yet unset charset MIME parameter is set to
6296 effectively making it impossible for the receiving MUA to automatically
6297 interpret the contents of the part.
6299 If this option is set, and the data was unambiguously identified as text
6300 data at first glance (by a
6304 file extension), then the original
6306 will not be overwritten.
6309 .It Va mime-alternative-favour-rich
6310 \*(BO If this variable is set then rich MIME alternative parts (e.g.,
6311 HTML) will be preferred in favour of included plain text versions when
6312 displaying messages, provided that a handler exists which produces
6313 output that can be (re)integrated into \*(UA's normal visual display.
6314 (E.g., at the time of this writing some newsletters ship their full
6315 content only in the rich HTML part, whereas the plain text part only
6316 contains topic subjects.)
6319 .It Va mime-counter-evidence
6322 field is used to decide how to handle MIME parts.
6323 Some MUAs however don't use
6325 or a similar mechanism to correctly classify content, but simply specify
6326 .Ql application/octet-stream ,
6327 even for plain text attachments like
6329 If this variable is set then \*(UA will try to classify such MIME
6330 message parts on its own, if possible, for example via a possibly
6331 existent attachment filename.
6332 A non-empty value may also be given, in which case a number is expected,
6333 actually a carrier of bits.
6334 Creating the bit-carrying number is a simple addition:
6335 .Bd -literal -offset indent
6336 ? !echo Value should be set to $((2 + 4 + 8))
6337 Value should be set to 14
6340 .Bl -bullet -compact
6342 If bit two is set (2) then the detected
6344 content-type will be carried along with the message and be used for
6346 .Va pipe-TYPE/SUBTYPE
6347 is responsible for the MIME part, shall that question arise;
6348 when displaying such a MIME part the part-info will indicate the
6349 overridden content-type by showing a plus-sign
6352 If bit three is set (4) then the counter-evidence is always produced
6353 and a positive result will be used as the MIME type, even forcefully
6354 overriding the parts given MIME type.
6356 If bit four is set (8) then as a last resort the actual content of
6357 .Ql application/octet-stream
6358 parts will be inspected, so that data which looks like plain text can be
6363 .It Va mimetypes-load-control
6364 This option can be used to control which of the
6366 databases are loaded by \*(UA, as furtherly described in the section
6367 .Sx "The mime.types files" .
6370 is part of the option value, then the user's personal
6372 file will be loaded (if it exists); likewise the letter
6374 controls loading of the system wide
6375 .Pa /etc/mime.types ;
6376 directives found in the user file take precedence, letter matching is
6378 If this option is not set \*(UA will try to load both files.
6379 Incorporation of the \*(UA-builtin MIME types cannot be suppressed,
6380 but they will be matched last.
6382 More sources can be specified by using a different syntax: if the
6383 value string contains an equals sign
6385 then it is instead parsed as a comma-separated list of the described
6388 pairs; the given filenames will be expanded and loaded, and their
6389 content may use the extended syntax that is described in the section
6390 .Sx "The mime.types files" .
6391 Directives found in such files always take precedence (are prepended to
6392 the MIME type cache).
6395 .It Va NAIL_EXTRA_RC
6396 The name of an optional startup file to be read last.
6397 This variable has an effect only if it is set in any of the
6398 .Sx "Resource files" ,
6399 it is not imported from the environment.
6400 Use this file for commands that are not understood by other POSIX
6405 .It Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup
6406 \*(BO\*(IN\*(OP Used to control usage of the users
6408 file for lookup of account credentials, as documented in the section
6409 .Sx "On URL syntax and credential lookup"
6413 .Sx "The .netrc file"
6414 documents the file format.
6418 If this variable has the value
6420 newly created local folders will be in Maildir format.
6424 Checks for new mail in the current folder each time the prompt is shown.
6425 A Maildir folder must be re-scanned to determine if new mail has arrived.
6426 If this variable is set to the special value
6428 then a Maildir folder will not be rescanned completely, but only
6429 timestamp changes are detected.
6433 \*(BO Causes the filename given in the
6436 and the sender-based filenames for the
6440 commands to be interpreted relative to the directory given in the
6442 variable rather than to the current directory,
6443 unless it is set to an absolute pathname.
6447 \*(BO If set, each message feed through the command given for
6449 is followed by a formfeed character
6453 .It Va password-USER@HOST , password-HOST , password
6454 \*(IN Variable chain that sets a password, which is used in case none has
6455 been given in the protocol and account-specific URL;
6456 as a last resort \*(UA will ask for a password on the user's terminal if
6457 the authentication method requires a password.
6458 Specifying passwords in a startup file is generally a security risk;
6459 the file should be readable by the invoking user only.
6461 .It Va password-USER@HOST
6462 \*(OU (see the chain above for \*(IN)
6463 Set the password for
6467 If no such variable is defined for a host,
6468 the user will be asked for a password on standard input.
6469 Specifying passwords in a startup file is generally a security risk;
6470 the file should be readable by the invoking user only.
6474 \*(BO Send messages to the
6476 command without performing MIME and character set conversions.
6480 .It Va pipe-TYPE/SUBTYPE
6481 When a MIME message part of type
6483 (case-insensitive) is displayed or quoted,
6484 its text is filtered through the value of this variable interpreted as
6488 forces interpretation of the message part as plain text, e.g.,
6489 .Ql set pipe-application/xml=@
6490 will henceforth display XML
6492 (The same could also be achieved by adding a MIME type marker with the
6495 And \*(OPally MIME type handlers may be defined via
6496 .Sx "The Mailcap files"
6497 \(em corresponding flag strings are shown in parenthesis below.)
6502 can in fact be used to adjust usage and behaviour of a following shell
6503 command specification by appending trigger characters to it, e.g., the
6504 following hypothetical command specification could be used:
6505 .Bd -literal -offset indent
6506 set pipe-X/Y="@*!++=@vim ${NAIL_FILENAME_TEMPORARY}"
6510 .Bl -tag -compact -width ".It Ql __"
6512 Simply by using the special
6514 prefix the MIME type (shell command) handler will only be invoked to
6515 display or convert the MIME part if the message is addressed directly
6516 and alone by itself.
6517 Use this trigger to disable this and always invoke the handler
6518 .Pf ( Cd x-mailx-always ) .
6521 If set the handler will not be invoked when a message is to be quoted,
6522 but only when it will be displayed
6523 .Pf ( Cd x-mailx-noquote ) .
6526 The command will be run asynchronously, i.e., without blocking \*(UA,
6527 which may be a handy way to display a, e.g., PDF file while also
6528 continuing to read the mail message
6529 .Pf ( Cd x-mailx-async ) .
6530 Asynchronous execution implies
6534 The command must be run on an interactive terminal, \*(UA will
6535 temporarily release the terminal to it
6536 .Pf ( Cd needsterminal ) .
6537 This flag is mutual exclusive with
6539 will only be used in interactive mode and implies
6543 Request creation of a zero-sized temporary file, the absolute pathname
6544 of which will be made accessable via the environment variable
6545 .Ev NAIL_FILENAME_TEMPORARY
6546 .Pf ( Cd x-mailx-tmpfile ) .
6547 If this trigger is given twice then the file will be unlinked
6548 automatically by \*(UA when the command loop is entered again at latest
6549 .Pf ( Cd x-mailx-tmpfile-unlink ) .
6550 (Don't use this for asynchronous handlers.)
6553 Normally the MIME part content is passed to the handler via standard
6554 input; if this flag is set then the data will instead be written into
6555 .Ev NAIL_FILENAME_TEMPORARY
6556 .Pf ( Cd x-mailx-tmpfile-fill ) ,
6557 the creation of which is implied; note however that in order to cause
6558 deletion of the temporary file you still have to use two plus signs
6563 To avoid ambiguities with normal shell command content you can use
6564 another at-sign to forcefully terminate interpretation of remaining
6566 (Any character not in this list will have the same effect.)
6570 Some information about the MIME part to be displayed is embedded into
6571 the environment of the shell command:
6574 .Bl -tag -compact -width ".It Ev _AIL__ILENAME__ENERATED"
6577 The MIME content-type of the part, if known, the empty string otherwise.
6580 .It Ev NAIL_CONTENT_EVIDENCE
6582 .Va mime-counter-evidence
6583 includes the carry-around-bit (2), then this will be set to the detected
6584 MIME content-type; not only then identical to
6585 .Ev \&\&NAIL_CONTENT
6589 .It Ev NAIL_FILENAME
6590 The filename, if any is set, the empty string otherwise.
6593 .It Ev NAIL_FILENAME_GENERATED
6597 .It Ev NAIL_FILENAME_TEMPORARY
6598 If temporary file creation has been requested through the command prefix
6599 this variable will be set and contain the absolute pathname of the
6604 The temporary directory that \*(UA uses.
6605 Usually identical to
6607 but guaranteed to be set and usable by child processes;
6608 to ensure the latter condition for
6615 .It Va pipe-EXTENSION
6616 This is identical to
6617 .Va pipe-TYPE/SUBTYPE
6620 (normalized to lowercase using character mappings of the ASCII charset)
6621 names a file extension, e.g.,
6623 Handlers registered using this method take precedence.
6626 .It Va pop3-auth-USER@HOST , pop3-auth-HOST , pop3-auth
6627 \*(OP\*(IN Variable chain that sets the POP3 authentication method.
6628 The only possible value as of now is
6630 which is thus the default.
6633 .Mx Va pop3-bulk-load
6634 .It Va pop3-bulk-load-USER@HOST , pop3-bulk-load-HOST , pop3-bulk-load
6635 \*(BO\*(OP When accessing a POP3 server \*(UA loads the headers of
6636 the messages, and only requests the message bodies on user request.
6637 For the POP3 protocol this means that the message headers will be
6639 If this option is set then \*(UA will download only complete messages
6640 from the given POP3 server(s) instead.
6642 .Mx Va pop3-keepalive
6643 .It Va pop3-keepalive-USER@HOST , pop3-keepalive-HOST , pop3-keepalive
6644 \*(OP POP3 servers close the connection after a period of inactivity;
6645 the standard requires this to be at least 10 minutes,
6646 but practical experience may vary.
6647 Setting this variable to a numeric value greater than
6651 command to be sent each value seconds if no other operation is performed.
6654 .It Va pop3-no-apop-USER@HOST , pop3-no-apop-HOST , pop3-no-apop
6655 \*(BO\*(OP Unless this variable is set the
6657 authentication method will be used when connecting to a POP3 server that
6661 is that the password is not sent in clear text over the wire and that
6662 only a single packet is sent for the user/password tuple.
6664 .Va pop3-no-apop-HOST
6667 .Mx Va pop3-use-starttls
6668 .It Va pop3-use-starttls-USER@HOST , pop3-use-starttls-HOST , pop3-use-starttls
6669 \*(BO\*(OP Causes \*(UA to issue a
6671 command to make an unencrypted POP3 session SSL/TLS encrypted.
6672 This functionality is not supported by all servers,
6673 and is not used if the session is already encrypted by the POP3S method.
6675 .Va pop3-use-starttls-HOST
6679 .It Va print-alternatives
6680 \*(BO When a MIME message part of type
6681 .Ql multipart/alternative
6682 is displayed and it contains a subpart of type
6684 other parts are normally discarded.
6685 Setting this variable causes all subparts to be displayed,
6686 just as if the surrounding part was of type
6687 .Ql multipart/mixed .
6691 The string shown when a command is accepted.
6692 Prompting may be prevented by either setting this to the null string
6695 The same XSI escape sequences that are understood by the
6697 command may be used within
6700 In addition, the following \*(UA specific additional sequences are
6707 is set, in which case it expands to
6711 is the default value of
6714 which will expand to
6716 if the last command failed and to
6720 which will expand to the name of the currently active
6722 if any, and to the empty string otherwise, and
6724 which will expand to the name of the currently active mailbox.
6725 (Note that the prompt buffer is size-limited, excess is cut off.)
6731 to encapsulate the expansions of the
6735 escape sequences as necessary to correctly display bidirectional text,
6736 this is not true for the final string that makes up
6738 as such, i.e., real BIDI handling is not supported.
6740 When a newer version of the
6742 .Sx "Command line editor"
6743 is used, any escape sequence must itself be encapsulated with another
6744 escape character for usage with the
6746 mechanism: \*(UA configures the control character
6752 \*(BO Suppresses the printing of the version when first invoked.
6756 If set, \*(UA starts a replying message with the original message
6757 prefixed by the value of the variable
6759 Normally, a heading consisting of
6760 .Dq Fromheaderfield wrote:
6761 is put before the quotation.
6766 variable, this heading is omitted.
6769 is assigned, the headers selected by the
6770 .Ic ignore Ns / Ns Ic retain
6771 commands are put above the message body,
6774 acts like an automatic
6780 is assigned, all headers are put above the message body and all MIME
6781 parts are included, making
6783 act like an automatic
6786 .Va quote-as-attachment .
6789 .It Va quote-as-attachment
6790 \*(BO Add the original message in its entirety as a
6792 MIME attachment when replying to a message.
6793 Note this works regardless of the setting of
6798 \*(OP Can be set in addition to
6800 Setting this turns on a more fancy quotation algorithm in that leading
6801 quotation characters are compressed and overlong lines are folded.
6803 can be set to either one or two (space separated) numeric values,
6804 which are interpreted as the maximum (goal) and the minimum line length,
6805 respectively, in a spirit rather equal to the
6807 program, but line-, not paragraph-based.
6808 If not set explicitly the minimum will reflect the goal algorithmically.
6809 The goal can't be smaller than the length of
6811 plus some additional pad.
6812 Necessary adjustments take place silently.
6815 .It Va recipients-in-cc
6816 \*(BO On group replies, specify only the sender of the original mail in
6818 and mention the other recipients in the secondary
6820 By default all recipients of the original mail will be addressed via
6825 If defined, gives the pathname of the folder used to record all outgoing
6827 If not defined, then outgoing mail is not saved.
6828 When saving to this folder fails the message is not sent,
6829 but instead saved to
6833 .It Va record-resent
6834 \*(BO If both this variable and the
6841 commands save messages to the
6843 folder as it is normally only done for newly composed messages.
6846 .It Va reply-in-same-charset
6847 \*(BO If this variable is set \*(UA first tries to use the same
6848 character set of the original message for replies.
6849 If this fails, the mechanism described in
6850 .Sx "Character sets"
6851 is evaluated as usual.
6854 .It Va reply_strings
6855 Can be set to a comma-separated list of (case-insensitive according to
6856 ASCII rules) strings which shall be recognized in addition to the
6859 reply message indicators \(en builtin are
6861 which is mandated by RFC 5322, as well as the german
6866 A list of addresses to put into the
6868 field of the message header.
6869 Members of this list are handled as if they were in the
6874 .It Va reply-to-honour
6877 header is honoured when replying to a message via
6881 This is a quadoption; if set without a value it defaults to
6885 .It Va rfc822-body-from_
6886 \*(BO This variable can be used to force displaying a so-called
6888 line for messages that are embedded into an envelope mail via the
6890 MIME mechanism, for more visual convenience.
6894 \*(BO Enable saving of (partial) messages in
6896 upon interrupt or delivery error.
6900 When \*(UA initially displays the message headers it determines the
6901 number to display by looking at the speed of the terminal.
6902 The faster the terminal, the more will be shown.
6903 This option specifies the number to use and overrides the calculation.
6904 This number is also used for scrolling with the
6907 Overall screen dimensions and pager usage is influenced by the
6908 environment variables
6916 .It Va searchheaders
6917 \*(BO Expand message-list specifiers in the form
6919 to all messages containing the substring
6923 The string search is case insensitive.
6927 \*(OP A comma-separated list of character set names that can be used in
6928 outgoing internet mail.
6929 The value of the variable
6931 is automatically appended to this list of character-sets.
6932 If no character set conversion capabilities are compiled into \*(UA then
6933 the only supported charset is
6936 .Va sendcharsets-else-ttycharset
6937 and refer to the section
6938 .Sx "Character sets"
6939 for the complete picture of character set conversion in \*(UA.
6942 .It Va sendcharsets-else-ttycharset
6943 \*(BO\*(OP If this variable is set, but
6945 is not, then \*(UA acts as if
6947 had been set to the value of the variable
6949 In effect this combination passes through the message data in the
6950 character set of the current locale (given that
6952 hasn't been set manually), i.e., without converting it to the
6954 fallback character set.
6955 Thus, mail message text will be in ISO-8859-1 encoding when send from
6956 within a ISO-8859-1 locale, and in UTF-8 encoding when send from within
6958 If no character set conversion capabilities are available in \*(UA then
6959 the only supported character set is
6964 An address that is put into the
6966 field of outgoing messages, quoting RFC 5322: the mailbox of the agent
6967 responsible for the actual transmission of the message.
6968 This field should normally not be used unless the
6970 field contains more than one address, on which case it is required.
6973 address is handled as if it were in the
6979 To use an alternate mail transport agent (MTA),
6980 set this option to the full pathname of the program to use.
6981 It may be necessary to set
6982 .Va sendmail-progname
6985 The MTA will be passed command line arguments from several possible
6986 sources: from the variable
6987 .Va sendmail-arguments
6988 if set, from the command line if given and the variable
6991 Argument processing of the MTA will be terminated with a
6995 The otherwise occurring implicit usage of the following MTA command line
6996 arguments can be disabled by setting the boolean option
6997 .Va sendmail-no-default-arguments
6998 (which will also disable passing
7002 (for not treating a line with only a dot
7004 character as the end of input),
7012 option is set); in conjunction with the
7014 command line option \*(UA will also pass
7020 .It Va sendmail-arguments
7021 Arguments to pass through to the Mail-Transfer-Agent can be given via
7023 The content of this variable will be split up in a vector of arguments
7024 which will be joined onto other possible MTA options:
7026 .Dl set sendmail-arguments='-t -X \&"/tmp/my log\&"'
7029 .It Va sendmail-no-default-arguments
7030 \*(BO Unless this option is set \*(UA will pass some well known
7031 standard command line options to the defined
7033 program, see there for more.
7036 .It Va sendmail-progname
7037 Many systems use a so-called
7039 environment to ensure compatibility with
7041 This works by inspecting the name that was used to invoke the mail
7043 If this variable is set then the mailwrapper (the program that is
7044 actually executed when calling
7046 will treat its contents as that name.
7052 \*(BO When sending a message wait until the MTA (including the builtin
7053 SMTP one) exits before accepting further commands.
7055 with this variable set errors reported by the MTA will be recognizable!
7056 If the MTA returns a non-zero exit status,
7057 the exit status of \*(ua will also be non-zero.
7061 \*(BO Setting this option causes \*(UA to start at the last message
7062 instead of the first one when opening a mail folder.
7066 \*(BO Causes \*(UA to use the sender's real name instead of the plain
7067 address in the header field summary and in message specifications.
7071 \*(BO Causes the recipient of the message to be shown in the header
7072 summary if the message was sent by the user.
7076 A string for use with the
7082 A string for use with the
7088 Must correspond to the name of a readable file if set.
7089 The file's content is then appended to each singlepart message
7090 and to the first part of each multipart message.
7091 Be warned that there is no possibility to edit the signature for an
7095 .It Va skipemptybody
7096 \*(BO If an outgoing message does not contain any text in its first or
7097 only message part, do not send it but discard it silently (see also the
7103 \*(OP Specifies a directory with CA certificates in PEM (Privacy
7104 Enhanced Mail) format for verification of S/MIME signed messages.
7107 .It Va smime-ca-file
7108 \*(OP Specifies a file with CA certificates in PEM format for
7109 verification of S/MIME signed messages.
7112 .It Va smime-cipher-USER@HOST , smime-cipher
7113 \*(OP Specifies the cipher to use when generating S/MIME encrypted
7114 messages (for the specified account).
7115 RFC 5751 mandates a default of
7118 Possible values are (case-insensitive and) in decreasing cipher strength:
7126 (DES EDE3 CBC, 168 bits; default if
7128 isn't available) and
7132 The actually available cipher algorithms depend on the cryptographic
7133 library that \*(UA uses.
7134 \*(OP Support for more cipher algorithms may be available through
7135 dynamic loading via, e.g.,
7136 .Xr EVP_get_cipherbyname 3
7137 (OpenSSL) if \*(UA has been compiled to support this.
7140 .It Va smime-crl-dir
7141 \*(OP Specifies a directory that contains files with CRLs in PEM format
7142 to use when verifying S/MIME messages.
7145 .It Va smime-crl-file
7146 \*(OP Specifies a file that contains a CRL in PEM format to use when
7147 verifying S/MIME messages.
7150 .It Va smime-encrypt-USER@HOST
7151 \*(OP If this variable is set, messages send to the given receiver are
7152 encrypted before sending.
7153 The value of the variable must be set to the name of a file that
7154 contains a certificate in PEM format.
7156 If a message is sent to multiple recipients,
7157 each of them for whom a corresponding variable is set will receive an
7158 individually encrypted message;
7159 other recipients will continue to receive the message in plain text
7161 .Va smime-force-encryption
7163 It is recommended to sign encrypted messages, i.e., to also set the
7168 .It Va smime-force-encryption
7169 \*(BO\*(OP Causes \*(UA to refuse sending unencrypted messages.
7172 .It Va smime-no-default-ca
7173 \*(BO\*(OP Don't load default CA locations when verifying S/MIME signed
7178 \*(BO\*(OP S/MIME sign outgoing messages with the user's private key
7179 and include the user's certificate as a MIME attachment.
7180 Signing a message enables a recipient to verify that the sender used
7181 a valid certificate,
7182 that the email addresses in the certificate match those in the message
7183 header and that the message content has not been altered.
7184 It does not change the message text,
7185 and people will be able to read the message as usual.
7187 .Va smime-sign-cert , smime-sign-include-certs
7189 .Va smime-sign-message-digest .
7191 .Mx Va smime-sign-cert
7192 .It Va smime-sign-cert-USER@HOST , smime-sign-cert
7193 \*(OP Points to a file in PEM format.
7194 For the purpose of signing and decryption this file needs to contain the
7195 user's private key as well as his certificate.
7199 is always derived from the value of
7201 (or, if that contains multiple addresses,
7203 For the purpose of encryption the recipient's public encryption key
7204 (certificate) is expected; the command
7206 can be used to save certificates of signed messages (the section
7207 .Sx "Signed and encrypted messages with S/MIME"
7208 gives some details).
7209 This mode of operation is usually driven by the specialized form.
7211 When decrypting messages the account is derived from the recipient
7216 of the message, which are searched for addresses for which such
7218 \*(UA always uses the first address that matches,
7219 so if the same message is sent to more than one of the user's addresses
7220 using different encryption keys, decryption might fail.
7222 .Mx Va smime-sign-include-certs
7223 .It Va smime-sign-include-certs-USER@HOST , smime-sign-include-certs
7224 \*(OP If used, this is supposed to a consist of a comma-separated list
7225 of files, each of which containing a single certificate in PEM format to
7226 be included in the S/MIME message in addition to the
7229 This is most useful for long certificate chains if it is desired to aid
7230 the receiving party's verification process.
7231 Note that top level certificates may also be included in the chain but
7232 don't play a role for verification.
7234 .Va smime-sign-cert .
7235 Remember that for this
7237 refers to the variable
7239 (or, if that contains multiple addresses,
7242 .Mx Va smime-sign-message-digest
7243 .It Va smime-sign-message-digest-USER@HOST , smime-sign-message-digest
7244 \*(OP Specifies the message digest to use when signing S/MIME messages.
7245 RFC 5751 mandates a default of
7247 Possible values are (case-insensitive and) in decreasing cipher strength:
7255 The actually available message digest algorithms depend on the
7256 cryptographic library that \*(UA uses.
7257 \*(OP Support for more message digest algorithms may be available
7258 through dynamic loading via, e.g.,
7259 .Xr EVP_get_digestbyname 3
7260 (OpenSSL) if \*(UA has been compiled to support this.
7261 Remember that for this
7263 refers to the variable
7265 (or, if that contains multiple addresses,
7271 \*(OP Normally \*(UA invokes the program defined via
7273 to transfer messages, as described in
7274 .Sx "On sending mail, and non-interactive mode" .
7277 variable will instead cause SMTP network connections be made to the
7278 server specified therein in order to directly submit the message.
7279 \*(UA knows about three different
7280 .Dq SMTP protocols :
7282 .Bl -bullet -compact
7284 The plain SMTP protocol (RFC 5321) that normally lives on the
7285 server port 25 and requires setting the
7286 .Va smtp-use-starttls
7287 variable to enter a SSL/TLS encrypted session state.
7288 Assign a value like \*(IN
7289 .Ql [smtp://][user[:password]@]server[:port]
7291 .Ql [smtp://]server[:port] )
7292 to choose this protocol.
7294 Then the so-called SMTPS which is supposed to live on server port 465
7295 and is automatically SSL/TLS secured.
7296 Unfortunately it never became a standardized protocol and may thus not
7297 be supported by your hosts network service database
7298 \(en in fact the port number has already been reassigned to other
7301 SMTPS is nonetheless a commonly offered protocol and thus can be
7302 chosen by assigning a value like \*(IN
7303 .Ql smtps://[user[:password]@]server[:port]
7305 .Ql smtps://server[:port] ) ;
7306 due to the mentioned problems it is usually necessary to explicitly
7311 Finally there is the SUBMISSION protocol (RFC 6409), which usually
7312 lives on server port 587 and is practically identically to the SMTP
7313 protocol from \*(UA's point of view beside that; it requires setting the
7314 .Va smtp-use-starttls
7315 variable to enter a SSL/TLS secured session state.
7316 Assign a value like \*(IN
7317 .Ql submission://[user[:password]@]server[:port]
7319 .Ql submission://server[:port] ) .
7322 For more on credentials etc. please see
7323 .Sx "On URL syntax and credential lookup" .
7324 The SMTP transfer is executed in a child process, which runs
7325 asynchronously unless either the
7330 If it receives a TERM signal, it will abort and save the message to
7335 .It Va smtp-auth-USER@HOST , smtp-auth-HOST , smtp-auth
7336 \*(OP Variable chain that sets the SMTP authentication method.
7343 as well as the \*(OPal methods
7349 method doesn't need any user credentials,
7351 requires a user name and all other methods require a user name and
7359 .Va smtp-auth-password
7361 .Va smtp-auth-user ) .
7366 .Va smtp-auth-USER@HOST :
7367 may override dependend on sender address in the variable
7370 .It Va smtp-auth-password
7371 \*(OP\*(OU Sets the global fallback password for SMTP authentication.
7372 If the authentication method requires a password, but neither
7373 .Va smtp-auth-password
7375 .Va smtp-auth-password-USER@HOST
7377 \*(UA will ask for a password on the user's terminal.
7379 .It Va smtp-auth-password-USER@HOST
7381 .Va smtp-auth-password
7382 for specific values of sender addresses, dependent upon the variable
7385 .It Va smtp-auth-user
7386 \*(OP\*(OU Sets the global fallback user name for SMTP authentication.
7387 If the authentication method requires a user name, but neither
7390 .Va smtp-auth-user-USER@HOST
7392 \*(UA will ask for a user name on the user's terminal.
7394 .It Va smtp-auth-user-USER@HOST
7397 for specific values of sender addresses, dependent upon the variable
7401 .It Va smtp-hostname
7402 \*(IN Normally \*(UA uses the variable
7404 to derive the necessary
7406 information to issue a
7411 can be used to use the
7413 from the SMTP account
7420 from the content of this variable (or, if that is the empty string,
7422 or the local hostname as a last resort).
7423 This often allows using an address that is itself valid but hosted by
7424 a provider other than which (in
7426 is about to send the message.
7427 Setting this variable also influences the generated
7430 .Mx Va smtp-use-starttls
7431 .It Va smtp-use-starttls-USER@HOST , smtp-use-starttls-HOST , smtp-use-starttls
7432 \*(BO\*(OP Causes \*(UA to issue a
7434 command to make an SMTP session SSL/TLS encrypted, i.e., to enable
7435 transport layer security.
7439 .It Va spam-interface
7440 \*(OP In order to use any of the spam-related commands (like, e.g.,
7442 the desired spam interface must be defined by setting this variable.
7443 Please refer to the manual section
7445 for the complete picture of spam handling in \*(UA.
7446 All or none of the following interfaces may be available:
7448 .Bl -tag -width ".It Ql _ilte_"
7454 .Pf ( Lk http://spamassassin.apache.org SpamAssassin )
7456 Different to the generic filter interface \*(UA will automatically add
7457 the correct arguments for a given command and has the necessary
7458 knowledge to parse the program's output.
7461 will have been compiled into the \*(UA binary if
7466 Shall it be necessary to define a specific connection type (rather than
7467 using a configuration file for that), the variable
7469 can be used as in, e.g.,
7470 .Ql -d server.example.com -p 783 .
7471 It is also possible to specify a per-user configuration via
7473 Note that this interface doesn't inspect the
7475 flag of a message for the command
7479 \*(UA will directly communicate with the
7485 stream socket as specified in
7487 It is possible to specify a per-user configuration via
7491 generic spam filter support via freely configurable hooks.
7492 This interface is ment for programs like
7496 and requires according behaviour in respect to the hooks' exit
7497 status for at least the command
7500 meaning a message is spam,
7504 for unsure and any other return value indicating a hard error);
7505 since the hooks can include shell code snippets diverting behaviour
7506 can be intercepted as necessary.
7508 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
7511 .Va spamfilter-spam ;
7514 contains examples for some programs.
7515 The process environment of the hooks will have the variables
7516 .Ev NAIL_TMPDIR , TMPDIR
7518 .Ev NAIL_FILENAME_GENERATED
7520 Note that spam score support for
7522 isn't supported unless the \*(OPtional regular expression support is
7524 .Va spamfilter-rate-scanscore
7531 \*(OP Messages that exceed this size won't be passed through to the
7533 .Va spam-interface .
7534 The default is 420000 bytes.
7537 .It Va spamc-command
7538 \*(OP The path to the
7542 .Va spam-interface .
7543 Note that the path is not expanded, but used
7545 A fallback path will have been compiled into the \*(UA binary if the
7546 executable had been found during compilation.
7549 .It Va spamc-arguments
7550 \*(OP Even though \*(UA deals with most arguments for the
7553 automatically, it may at least sometimes be desirable to specifiy
7554 connection-related ones via this variable, e.g.,
7555 .Ql -d server.example.com -p 783 .
7559 \*(OP Specify a username for per-user configuration files for the
7561 .Va spam-interface .
7562 If this is set to the empty string then \*(UA will use the name of the
7568 \*(OP Specify the path of the
7570 domain socket on which
7572 listens for connections for the
7574 .Va spam-interface .
7575 Note that the path is not expanded, but used
7580 \*(OP Specify a username for per-user configuration files for the
7582 .Va spam-interface .
7583 If this is set to the empty string then \*(UA will use the name of the
7592 .It Va spamfilter-ham , spamfilter-noham , \
7593 spamfilter-nospam , spamfilter-rate , spamfilter-spam
7594 \*(OP Command and argument hooks for the
7596 .Va spam-interface .
7599 contains examples for some programs.
7602 .It Va spamfilter-rate-scanscore
7603 \*(OP Because of the generic nature of the
7606 spam scores are not supported for it by default, but if the \*(OPtional
7607 regular expression support is available then setting this variable can
7608 be used to overcome this restriction.
7609 It is interpreted as follows: first a number (digits) is parsed that
7610 must be followed by a semicolon
7612 and an extended regular expression.
7613 Then the latter is used to parse the first output line of the
7615 hook, and, in case the evaluation is successful, the group that has been
7616 specified via the number is interpreted as a floating point scan score.
7620 \*(OP Specifies a directory with CA certificates in PEM (Pricacy
7621 Enhanced Mail) for verification of of SSL/TLS server certificates.
7623 .Xr SSL_CTX_load_verify_locations 3
7624 for more information.
7628 \*(OP Specifies a file with CA certificates in PEM format for
7629 verification of SSL/TLS server certificates.
7631 .Xr SSL_CTX_load_verify_locations 3
7632 for more information.
7635 .It Va ssl-cert-USER@HOST , ssl-cert-HOST , ssl-cert
7636 \*(OP Variable chain that sets the file name for a SSL/TLS client
7637 certificate required by some servers.
7638 This is a direct interface to the
7642 function of the OpenSSL library, if available.
7644 .Mx Va ssl-cipher-list
7645 .It Va ssl-cipher-list-USER@HOST , ssl-cipher-list-HOST , ssl-cipher-list
7646 \*(OP Specifies a list of ciphers for SSL/TLS connections.
7647 This is a direct interface to the
7651 function of the OpenSSL library, if available; see
7653 for more information.
7654 By default \*(UA doesn't set a list of ciphers, which in effect will use a
7656 specific cipher (protocol standards ship with a list of acceptable
7657 ciphers), possibly cramped to what the actually used SSL/TLS library
7658 supports \(en the manual section
7659 .Sx "An example configuration"
7660 also contains a SSL/TLS use case.
7663 .It Va ssl-config-file
7664 \*(OP If this variable is set \*(UA will call
7665 .Xr CONF_modules_load_file 3
7666 to allow OpenSSL to be configured according to the host system wide
7668 If a non-empty value is given then this will be used to specify the
7669 configuration file to be used instead of the global OpenSSL default;
7670 note that in this case it is an error if the file cannot be loaded.
7671 The application name will always be passed as
7676 \*(OP Specifies a file that contains a CRL in PEM format to use when
7677 verifying SSL/TLS server certificates.
7681 \*(OP Specifies a directory that contains files with CRLs in PEM format
7682 to use when verifying SSL/TLS server certificates.
7685 .It Va ssl-key-USER@HOST , ssl-key-HOST , ssl-key
7686 \*(OP Variable chain that sets the file name for the private key of
7687 a SSL/TLS client certificate.
7688 If unset, the name of the certificate file is used.
7689 The file is expected to be in PEM format.
7690 This is a direct interface to the
7694 function of the OpenSSL library, if available.
7697 .It Va ssl-method-USER@HOST , ssl-method-HOST , ssl-method
7699 \*(OB Please use the newer and more flexible
7701 instead: if both values are set,
7703 will take precedence!
7704 Can be set to the following values, the actually used
7706 specification to which it is mapped is shown in parenthesis:
7708 .Pf ( Ql -ALL, TLSv1.2 ) ,
7710 .Pf ( Ql -ALL, TLSv1.1 ) ,
7712 .Pf ( Ql -ALL, TLSv1 )
7715 .Pf ( Ql -ALL, SSLv3 ) ;
7720 and thus includes the SSLv3 protocol.
7721 Note that SSLv2 is no longer supported at all.
7724 .It Va ssl-no-default-ca
7725 \*(BO\*(OP Don't load default CA locations to verify SSL/TLS server
7729 .It Va ssl-protocol-USER@HOST , ssl-protocol-HOST , ssl-protocol
7730 \*(OP Specify the used SSL/TLS protocol.
7731 This is a direct interface to the
7735 function of the OpenSSL library, if available;
7736 otherwise an \*(UA internal parser is used which understands the
7737 following subset of (case-insensitive) command strings:
7743 as well as the special value
7745 Multiple specifications may be given via a comma-separated list which
7746 ignores any whitespace.
7749 plus prefix will enable a protocol, a
7751 minus prefix will disable it, so that
7753 will enable only the TLSv1.2 protocol.
7755 It depends upon the used TLS/SSL library which protocols are actually
7756 supported and which protocols are used if
7758 is not set, but note that SSLv2 is no longer supported at all and
7760 Especially for older protocols explicitly securing
7762 may be worthwile, see
7763 .Sx "An example configuration" .
7767 \*(OP Gives the pathname to an entropy daemon socket, see
7769 Not all SSL/TLS libraries support this.
7772 .It Va ssl-rand-file
7773 \*(OP Gives the filename to a file with random entropy data, see
7774 .Xr RAND_load_file 3 .
7775 If this variable is not set, or set to the empty string, or if the
7776 filename expansion failed, then
7777 .Xr RAND_file_name 3
7778 will be used to create the filename if, and only if,
7780 documents that the SSL PRNG is not yet sufficiently seeded.
7781 If \*(UA successfully seeded the SSL PRNG then it'll update the file via
7782 .Xr RAND_write_file 3 .
7783 This variable is only used if
7785 is not set (or not supported by the SSL/TLS library).
7788 .It Va ssl-verify-USER@HOST , ssl-verify-HOST , ssl-verify
7789 \*(OP Variable chain that sets the action to be performed if an error
7790 occurs during SSL/TLS server certificate validation.
7791 Valid (case-insensitive) values are
7793 (fail and close connection immediately),
7795 (ask whether to continue on standard input),
7797 (show a warning and continue),
7799 (do not perform validation).
7805 If only set without an assigned value, then this option inhibits the
7810 header fields that include obvious references to \*(UA.
7811 There are two pitfalls associated with this:
7812 First, the message id of outgoing messages is not known anymore.
7813 Second, an expert may still use the remaining information in the header
7814 to track down the originating mail user agent.
7819 suppression doesn't occur.
7823 \*(BY\*(OP If terminal capability queries
7824 .Pf ( Xr termcap 5 ,
7826 are supported and this option is set then \*(UA will try to
7828 .Dq alternate screen
7829 when in interactive mode if the
7831 inal allows to do so, so that the terminal will go back to the
7832 normal screen, leaving all the text there intact, when \*(UA exits.
7835 even when supported for this to produce appealing results the used
7837 and possibly configured
7838 .Va pipe-TYPE/SUBTYPE
7839 applications that take control over the terminal need to have
7840 corresponding support and must be configured accordingly, too, e.g., the
7842 pager should be driven with the
7848 If defined, gives the number of lines of a message to be displayed
7851 normally, the first five lines are printed.
7855 The character set of the terminal \*(UA operates on,
7856 and the one and only supported character set that \*(UA can use if no
7857 character set conversion capabilities have been compiled into it,
7858 in which case it defaults to ISO-8859-1 unless it can deduce a value
7862 Refer to the section
7863 .Sx "Character sets"
7864 for the complete picture about character sets.
7867 .It Va user-HOST , user
7868 \*(IN Variable chain that sets a global fallback user name, which is
7869 used in case none has been given in the protocol and account-specific
7871 This variable defaults to the value of the first of
7875 that is set (the former being SystemV and POSIX standard, the latter BSD).
7879 \*(BO Setting this option enables upward compatibility with \*(UA
7880 version 15.0 in respect to which configuration options are available and
7881 how they are handled.
7882 This manual uses \*(IN and \*(OU to refer to the new and the old way of
7883 doing things, respectively.
7887 \*(BO Setting this option, also controllable via the command line option
7889 causes \*(UA to be more verbose, e.g., it will display obsoletion
7890 warnings and SSL/TLS certificate chains.
7891 Even though marked \*(BO this option may be set twice in order to
7892 increase the level of verbosity even more, in which case even details of
7893 the actual message delivery and protocol conversations are shown.
7896 is sufficient to disable verbosity as such.
7902 .It Va version , version-major , version-minor , version-update
7903 \*(RO \*(UA version information: the first variable contains a string
7904 containing the complete version identification \(en this is identical to
7905 the output of the command
7907 The latter three contain only digits: the major, minor and update
7911 .It Va writebackedited
7912 If this variable is set messages modified using the
7916 commands are written back to the current folder when it is quit;
7917 it is only honoured for writable folders in MBOX format, though.
7918 Note that the editor will be pointed to the raw message content in that
7919 case, i.e., neither MIME decoding nor decryption will have been
7920 performed, and proper RFC 4155
7922 quoting of newly added or edited content is also left as an excercise to
7926 .\" }}} (INTERNAL VARIABLES)
7929 .\" .Sh ENVIRONMENT {{{
7933 .Dq environment variable
7934 should be considered an indication that the following variables are
7935 either standardized as being vivid parts of process environments, or
7936 are commonly found in there.
7937 The process environment is inherited from the
7939 once \*(UA is started, and unless otherwise explicitly noted variables
7940 in there integrate into the normal handling of
7941 .Sx "INTERNAL VARIABLES" ,
7942 from \*(UAs point of view, i.e., they can be
7944 as such in resource files and need not necessarily come from the process
7945 environment and be managed via
7949 E.g., the following example, applicable to a POSIX shell, sets the
7951 environment variable for \*(UA only, and beforehand exports the
7953 in order to affect any further processing in the running shell:
7955 .Bd -literal -offset indent
7956 $ EDITOR="vim -u ${HOME}/.vimrc"
7958 $ COLUMNS=80 \*(ua -R
7961 .Bl -tag -width ".It Ev _AILR_"
7964 The user's preferred width in column positions for the terminal screen
7966 Queried and used once on program startup.
7970 The name of the file to use for saving aborted messages if
7972 is set; this defaults to
7980 Pathname of the text editor to use in the
7984 .Sx "TILDE ESCAPES" .
7985 A default editor is used if this value is not defined.
7989 The user's home directory.
7990 This variable is only used when it resides in the process environment.
7993 to update the value at runtime.
8000 .It Ev LANG , LC_ALL , LC_COLLATE , LC_CTYPE , LC_MESSAGES
8004 .Sx "Character sets" .
8008 The user's preferred number of lines on a page or the vertical screen
8009 or window size in lines.
8010 Queried and used once on program startup.
8014 Pathname of the directory lister to use in the
8016 command when operating on local mailboxes.
8019 (path search through
8024 Force identification as the given user, i.e., identical to the
8026 command line option.
8027 This variable is standardized and therefore used in preference to the
8030 it is only used when it resides in the process environment.
8031 \*(ID The variable can be updated at runtime via
8033 but without having an effect on \*(UA itself.
8037 Is used as the user's mailbox, if set.
8038 Otherwise, a system-dependent default is used.
8039 Supports a logical subset of the special conventions that are documented
8048 \*(OP Overrides the default path search for
8049 .Sx "The Mailcap files" ,
8050 which is defined in the standard RFC 1524 as
8051 .Ql ~/.mailcap:\:/etc/mailcap:\:/usr/etc/mailcap:\:/usr/local/etc/mailcap .
8052 .\" TODO we should have a mailcaps-default virtual RDONLY option!
8053 (\*(UA makes it a configuration option, however.)
8054 Note this is not a search path, but a path search.
8058 Is used as a startup file instead of
8061 When \*(UA scripts are invoked on behalf of other users,
8062 either this variable should be set to
8066 command line option should be used in order to avoid side-effects from
8067 reading their configuration files.
8068 This variable is only used when it resides in the process environment.
8072 The name of the user's mbox file.
8073 A logical subset of the special conventions that are documented for the
8078 The fallback default is
8083 Traditionally this secondary mailbox is used as the file to save
8084 messages from the system mailbox that have been read.
8086 .Sx "Message states" .
8089 .It Ev NAIL_NO_SYSTEM_RC
8090 If this variable is set then reading of
8092 at startup is inhibited, i.e., the same effect is achieved as if \*(UA
8093 had been started up with the option
8095 This variable is only used when it resides in the process environment.
8099 \*(IN\*(OP This variable overrides the default location of the user's
8105 Pathname of the program to use in the more command or when the
8108 The default paginator is
8110 (path search through
8115 A list of directories that is searched by the shell when looking for
8116 commands (as such only recognized in the process environment).
8120 The shell to use for the commands
8126 and when starting subprocesses.
8127 A default shell is used if this option is not defined.
8131 \*(OP The terminal type for which output is to be prepared.
8132 For extended colour and font control please refer to
8133 .Sx "Coloured display" ,
8134 and for terminal capability queries to
8139 Used as directory for temporary files instead of
8142 This variable is only used when it resides in the process environment.
8145 to update the value at runtime.
8149 This variable comes from the BSD world and is only used if the POSIX
8150 standard environment variable
8152 which originates in SysV
8155 Force identification as the given user, i.e., identical to the
8157 command line option.
8158 This variable is only used when it resides in the process environment.
8159 \*(ID The variable can be updated at runtime via
8161 but without having an effect on \*(UA itself.
8165 Pathname of the text editor to use in the
8169 .Sx "TILDE ESCAPES" .
8177 .Bl -tag -width ".It Pa _etc/mime.type_"
8179 File giving initial commands.
8182 System wide initialization file.
8186 \*(OP Personal MIME type handler definition file, see
8187 .Sx "The Mailcap files" .
8188 (RFC 1524 location, the actual path is a configuration option.)
8192 \*(OP System wide MIME type handler definition file, see
8193 .Sx "The Mailcap files" .
8194 (RFC 1524 location, the actual path is a configuration option.)
8197 .It Pa ~/.mime.types
8198 Personal MIME types, see
8199 .Sx "The mime.types files" .
8202 .It Pa /etc/mime.types
8203 System wide MIME types, see
8204 .Sx "The mime.types files" .
8208 \*(IN\*(OP The default location of the users
8210 file \(en the section
8211 .Sx "The .netrc file"
8212 documents the file format.
8215 .\" .Ss "The mime.types files" {{{
8216 .Ss "The mime.types files"
8218 When sending messages \*(UA tries to determine the content type of all
8220 When displaying message content or attachments \*(UA uses the content
8221 type to decide wether it can directly display data or wether it needs to
8222 deal with content handlers.
8223 It learns about MIME types and how to treat them by reading
8225 files, the loading of which can be controlled by setting the variable
8226 .Va mimetypes-load-control .
8229 can also be used to deal with MIME types.)
8231 files have the following syntax:
8234 .Dl type/subtype extension [extension ...]
8239 are strings describing the file contents, and one or multiple
8241 s, separated by whitespace, name the part of a filename starting after
8242 the last dot (of interest).
8243 Comments may be introduced anywhere on a line with a number sign
8245 causing the remaining line to be discarded.
8247 \*(UA also supports an extended, non-portable syntax in specially
8248 crafted files, which can be loaded via the alternative value syntax of
8249 .Va mimetypes-load-control
8250 and prepends an optional
8254 .Dl [type-marker ]type/subtype extension [extension ...]
8257 The following type markers are supported:
8260 .Bl -tag -compact -offset indent -width ".It Ar _n_u"
8262 Treat message parts with this content as plain text.
8267 Treat message parts with this content as HTML tagsoup.
8268 If the \*(OPal HTML-tagsoup-to-text converter is not available treat
8269 the content as plain text instead.
8273 but instead of falling back to plain text require an explicit content
8274 handler to be defined.
8279 for sending messages:
8281 .Va mime-allow-text-controls ,
8282 .Va mimetypes-load-control .
8283 For reading etc. messages:
8284 .Sx "HTML mail and MIME attachments" ,
8285 .Sx "The Mailcap files" ,
8287 .Va mime-counter-evidence ,
8288 .Va mimetypes-load-control ,
8289 .Va pipe-TYPE/SUBTYPE ,
8290 .Va pipe-EXTENSION .
8293 .\" .Ss "The Mailcap files" {{{
8294 .Ss "The Mailcap files"
8297 .Dq User Agent Configuration Mechanism
8298 which \*(UA \*(OPally supports.
8299 It defines a file format to be used to inform mail user agent programs
8300 about the locally-installed facilities for handling various data
8301 formats, i.e., about commands and how they can be used to display, edit
8302 etc. MIME part contents, as well as a default path search that includes
8303 multiple possible locations of
8307 environment variable that can be used to overwrite that (repeating here
8308 that it is not a search path, but instead a path search specification).
8309 Any existing files will be loaded in sequence, appending any content to
8310 the list of MIME type handler directives.
8314 files consist of a set of newline separated entries.
8315 Comment lines start with a number sign
8317 (in the first column!) and are ignored.
8318 Empty lines are also ignored.
8319 All other lines form individual entries that must adhere to the syntax
8321 To extend a single entry (not comment) its line can be continued on
8322 follow lines if newline characters are
8324 by preceding them with the backslash character
8326 The standard doesn't specify how leading whitespace of follow lines is
8327 to be treated, therefore \*(UA retains it.
8331 entries consist of a number of semicolon
8333 separated fields, and the backslash
8335 character can be used to escape any following character including
8336 semicolon and itself.
8337 The first two fields are mandatory and must occur in the specified
8338 order, the remaining fields are optional and may appear in any order.
8339 Leading and trailing whitespace of content is ignored (removed).
8342 The first field defines the MIME
8344 the entry is about to handle (case-insensitively, and no backslash
8345 escaping is possible in this field).
8346 If the subtype is specified as an asterisk
8348 the entry is ment to match all subtypes of the named type, e.g.,
8350 would match any audio type.
8351 The second field defines the shell command which shall be used to
8353 MIME parts of the given type; it is implicitly called the
8360 shell commands message (MIME part) data is passed via standard input
8361 unless the given shell command includes one or more instances of the
8364 in which case these instances will be replaced with a temporary filename
8365 and the data will have been stored in the file that is being pointed to.
8368 shell commands data is assumed to be generated on standard output unless
8369 the given command includes (one ore multiple)
8371 In any case any given
8373 format is replaced with a(n already) properly quoted filename.
8374 Note that when a command makes use of a temporary file via
8376 then \*(UA will remove it again, as if the
8377 .Cd x-mailx-tmpfile ,
8378 .Cd x-mailx-tmpfile-fill
8380 .Cd x-mailx-tmpfile-unlink
8381 flags had been set; see below for more.
8384 The optional fields either define a shell command or an attribute (flag)
8385 value, the latter being a single word and the former being a keyword
8386 naming the field followed by an equals sign
8388 succeeded by a shell command, and as usual for any
8390 content any whitespace surrounding the equals sign will be removed, too.
8391 Optional fields include the following:
8394 .Bl -tag -width textualnewlines
8396 A program that can be used to compose a new body or body part in the
8403 field, but is to be used when the composing program needs to specify the
8405 header field to be applied to the composed data.
8409 A program that can be used to edit a body or body part in the given
8414 A program that can be used to print a message or body part in the given
8419 Specifies a program to be run to test some condition, e.g., the machine
8420 architecture, or the window system in use, to determine whether or not
8421 this mailcap entry applies.
8422 If the test fails, a subsequent mailcap entry should be sought; also see
8423 .Cd x-mailx-test-once .
8425 .It Cd needsterminal
8426 This flag field indicates that the given shell command must be run on
8427 an interactive terminal.
8428 \*(UA will temporarily release the terminal to the given command in
8429 interactive mode, in non-interactive mode this entry will be entirely
8430 ignored; this flag implies
8431 .Cd x-mailx-noquote .
8433 .It Cd copiousoutput
8434 A flag field which indicates that the output of the
8436 command will be an extended stream of textual output that can be
8437 (re)integrated into \*(UA's normal visual display.
8438 It is mutually exclusive with
8441 .Cd x-mailx-always .
8443 .It Cd textualnewlines
8444 A flag field which indicates that this type of data is line-oriented and
8447 all newlines should be converted to canonical form (CRLF) before
8448 encoding, and will be in that form after decoding.
8452 This field gives a file name format, in which
8454 will be replaced by a random string, the joined combination of which
8455 will be used as the filename denoted by
8456 .Ev NAIL_FILENAME_TEMPORARY .
8457 One could specify that a GIF file being passed to an image viewer should
8458 have a name ending in
8461 .Ql nametemplate=%s.gif .
8462 Note that \*(UA ignores the name template unless that solely specifies
8463 a filename suffix that consists of (ASCII) alphabetic and numeric
8464 characters, the underscore and dot only.
8467 Names a file, in X11 bitmap (xbm) format, which points to an appropriate
8468 icon to be used to visually denote the presence of this kind of data.
8469 This field is not used by \*(UA.
8472 A textual description that describes this type of data.
8474 .It Cd x-mailx-always
8475 Extension flag field that denotes that the given
8477 command shall be executed even if multiple messages will be displayed
8479 Normally messages which require external viewers that produce output
8480 which doesn't integrate into \*(UA's visual display (i.e., don't have
8482 set) have to be addressed directly and individually.
8483 (To avoid cases where, e.g., a thousand PDF viewer instances are spawned
8486 .It Cd x-mailx-even-if-not-interactive
8487 An extension flag test field \(em by default handlers without
8489 are entirely ignored in non-interactive mode, but if this flag is set
8490 then their use will be considered.
8491 It is an error if this flag is set for commands that use the flag
8494 .It Cd x-mailx-noquote
8495 An extension flag field that indicates that even a
8498 command shall not be used to generate message quotes
8499 (as it would be by default).
8501 .It Cd x-mailx-async
8502 Extension flag field that denotes that the given
8504 command shall be executed asynchronously, without blocking \*(UA.
8505 Cannot be used in conjunction with
8508 .It Cd x-mailx-test-once
8509 Extension flag which denotes wether the given
8511 command shall be evaluated once only and the (boolean) result be cached.
8512 This is handy if some global unchanging condition is to be queried, like
8513 .Dq running under the X Window System .
8515 .It Cd x-mailx-tmpfile
8516 Extension flag field that requests creation of a zero-sized temporary
8517 file, the name of which is to be placed in the environment variable
8518 .Ev NAIL_FILENAME_TEMPORARY .
8519 It is an error to use this flag with commands that include a
8523 .It Cd x-mailx-tmpfile-fill
8524 Normally the MIME part content is passed to the handler via standard
8525 input; if this flag is set then the data will instead be written into
8527 .Cd x-mailx-tmpfile .
8528 In order to cause deletion of the temporary file you will have to set
8529 .Cd x-mailx-tmpfile-unlink
8531 It is an error to use this flag with commands that include a
8535 .It Cd x-mailx-tmpfile-unlink
8536 Extension flag field that requests that the temporary file shall be
8537 deleted automatically when the command loop is entered again at latest.
8538 (Don't use this for asynchronous handlers.)
8539 It is an error to use this flag with commands that include a
8541 format, or without also setting
8544 .Cd x-mailx-tmpfile-fill .
8546 .It Cd x-mailx-tmpfile-keep
8549 implies the three tmpfile related flags above, but if you want, e.g.,
8551 and deal with the temporary file yourself, you can add in this flag to
8553 .Cd x-mailx-tmpfile-unlink .
8558 The standard includes the possibility to define any number of additional
8559 entry fields, prefixed by
8561 Flag fields apply to the entire
8563 entry \(em in some unusual cases, this may not be desirable, but
8564 differentiation can be accomplished via separate entries, taking
8565 advantage of the fact that subsequent entries are searched if an earlier
8566 one does not provide enough information.
8569 command needs to specify the
8573 command shall not, the following will help out the latter (with enabled
8577 level \*(UA will show informations about handler evaluation):
8579 .Bd -literal -offset indent
8580 application/postscript; ps-to-terminal %s; needsterminal
8581 application/postscript; ps-to-terminal %s; compose=idraw %s
8585 In fields any occurrence of the format string
8587 will be replaced by the
8590 Named parameters from the
8592 field may be placed in the command execution line using
8594 followed by the parameter name and a closing
8597 The entire parameter should appear as a single command line argument,
8598 regardless of embedded spaces; thus:
8600 .Bd -literal -offset indent
8602 Content-type: multipart/mixed; boundary=42
8605 multipart/*; /usr/local/bin/showmulti \e
8606 %t %{boundary} ; composetyped = /usr/local/bin/makemulti
8608 # Executed shell command
8609 /usr/local/bin/showmulti multipart/mixed 42
8613 .\" TODO v15: Mailcap: %n,%F
8614 Note that \*(UA doesn't support handlers for multipart MIME parts as
8615 shown in this example (as of today).
8616 \*(UA doesn't support the additional formats
8620 An example file, also showing how to properly deal with the expansion of
8622 which includes any quotes that are necessary to make it a valid shell
8623 argument by itself and thus will cause undesired behaviour when placed
8624 in additional user-provided quotes:
8626 .Bd -literal -offset indent
8628 text/richtext; richtext %s; copiousoutput
8630 text/x-perl; perl -cWT %s
8634 trap "rm -f ${infile}" EXIT\e; \e
8635 trap "exit 75" INT QUIT TERM\e; \e
8637 x-mailx-async; x-mailx-tmpfile-keep
8639 application/*; echo "This is \e"%t\e" but \e
8640 is 50 \e% Greek to me" \e; < %s head -c 1024 | cat -vET; \e
8641 copiousoutput; x-mailx-noquote
8646 .Sx "HTML mail and MIME attachments" ,
8647 .Sx "The mime.types files" ,
8650 .Va mime-counter-evidence ,
8651 .Va pipe-TYPE/SUBTYPE ,
8652 .Va pipe-EXTENSION .
8655 .\" .Ss "The .netrc file" {{{
8656 .Ss "The .netrc file"
8660 file contains user credentials for machine accounts.
8661 The default location in the user's
8663 directory may be overridden by the
8665 environment variable.
8666 The file consists of space, tabulator or newline separated tokens.
8667 \*(UA implements a parser that supports a superset of the original BSD
8668 syntax, but users should nonetheless be aware of portability glitches
8669 of that file format, shall their
8671 be usable across multiple programs and platforms:
8674 .Bl -bullet -compact
8676 BSD doesn't support single, but only double quotation marks, e.g.,
8677 .Ql password="pass with spaces" .
8679 BSD (only?) supports escaping of single characters via a backslash
8680 (e.g., a space can be escaped via
8682 in- as well as outside of a quoted string.
8684 BSD doesn't require the final quotation mark of the final user input token.
8686 At least Hewlett-Packard seems to support a format which also allows
8687 tokens to be separated with commas \(en this format is not supported!
8689 Whereas other programs may require that the
8691 file is accessible by only the user if it contains a
8697 \*(UA will always require these strict permissions.
8701 Of the following list of supported tokens \*(UA only uses (and caches)
8706 At runtime the command
8708 can be used to control \*(UAs
8712 .Bl -tag -width password
8713 .It Cd machine Ar name
8714 The hostname of the entries' machine, lowercase-normalized by \*(UA
8716 Any further file content, until either end-of-file or the occurrence
8721 first-class token is bound (only related) to the machine
8724 As an extension that shouldn't be the cause of any worries
8725 \*(UA supports a single wildcard prefix for
8727 .Bd -literal -offset indent
8728 machine *.example.com login USER password PASS
8729 machine pop3.example.com login USER password PASS
8730 machine smtp.example.com login USER password PASS
8736 .Ql pop3.example.com ,
8740 .Ql local.smtp.example.com .
8741 Note that in the example neither
8742 .Ql pop3.example.com
8744 .Ql smtp.example.com
8745 will be matched by the wildcard, since the exact matches take
8746 precedence (it is however faster to specify it the other way around).
8751 except that it is a fallback entry that is used shall none of the
8752 specified machines match; only one default token may be specified,
8753 and it must be the last first-class token.
8755 .It Cd login Ar name
8756 The user name on the remote machine.
8758 .It Cd password Ar string
8759 The user's password on the remote machine.
8761 .It Cd account Ar string
8762 Supply an additional account password.
8763 This is merely for FTP purposes.
8765 .It Cd macdef Ar name
8767 A macro is defined with the specified
8769 it is formed from all lines beginning with the next line and continuing
8770 until a blank line is (consecutive newline characters are) encountered.
8773 entries cannot be utilized by multiple machines, too, but must be
8774 defined following the
8776 they are intended to be used with.)
8779 exists, it is automatically run as the last step of the login process.
8780 This is merely for FTP purposes.
8787 .\" .Sh EXAMPLES {{{
8790 .\" .Ss "An example configuration" {{{
8791 .Ss "An example configuration"
8793 .Bd -literal -offset indent
8794 # This example assumes v15.0 compatibility mode
8797 # Where are the up-to-date SSL certificates?
8798 #set ssl-ca-dir=/etc/ssl/certs
8799 set ssl-ca-file=/etc/ssl/certs/ca-certificates.crt
8801 # (Since we manage up-to-date ones explicitly, don't use any,
8802 # possibly outdated, default certificates shipped with OpenSSL
8803 set ssl-no-default-ca
8805 # Don't use protocols older than TLS v1.2.
8806 # Change this only when the remote server doesn't support it:
8807 # maybe use ssl-protocol-HOST (or -USER@HOST) syntax to define
8808 # such explicit exceptions, then
8809 set ssl-protocol="-ALL,+TLSv1.2"
8811 # Explicitly define the list of ciphers, which may improve security,
8812 # especially with protocols older than TLS v1.2. See ciphers(1).
8813 # Hint: it is important to include "@STRENGTH": only with it the
8814 # final list will be sorted by algorithm strength.
8815 # This is an example: in reality it is possibly best to only use
8816 # ssl-cipher-list-HOST (or -USER@HOST), as necessary, again..
8817 set ssl-cipher-list="ALL:!aNULL:!MEDIUM:!LOW:\e
8818 !MD5:!RC4:!EXPORT:@STRENGTH"
8820 # Request strict transport security checks!
8821 set ssl-verify=strict
8823 # Essential setting: select allowed character sets
8824 set sendcharsets=utf-8,iso-8859-1
8826 # A very kind option: when replying to a message, first try to
8827 # use the same encoding that the original poster used herself!
8828 set reply-in-same-charset
8830 # When replying to or forwarding a message the comment and name
8831 # parts of email addresses are removed unless this variable is set
8834 # When sending messages, wait until the Mail-Transfer-Agent finishs.
8835 # Only like this you'll be able to see errors reported through the
8836 # exit status of the MTA (including the builtin SMTP one)!
8839 # Only use builtin MIME types, no mime.types(5) files
8840 set mimetypes-load-control
8842 # Default directory where we act in (relative to $HOME)
8844 # A leading "+" (often) means: under *folder*
8845 # *record* is used to save copies of sent messages
8846 set MBOX=+mbox.mbox record=+sent.mbox DEAD=+dead.mbox
8848 # Make "file mymbox" and "file myrec" go to..
8849 shortcut mymbox %:+mbox.mbox myrec +sent.mbox
8851 # Not really optional, e.g., for S/MIME
8852 set from="Your Name <youremail@domain>"
8854 # It may be necessary to set hostname and/or smtp-hostname
8855 # if the "SERVER" of smtp and "domain" of from don't match.
8856 # The `urlencode' command can be used to encode USER and PASS
8857 set smtp=(smtp[s]/submission)://[USER[:PASS]@]SERVER[:PORT] \e
8858 smtp-auth=login/plain... \e
8861 # Never refuse to start into interactive mode, and more
8863 colour-pager crt= \e
8864 followup-to followup-to-honour=ask-yes \e
8865 history-file=+.\*(uahist history-size=-1 history-gabby \e
8866 mime-counter-evidence=0xE \e
8867 prompt="\e033[31m?\e?[\e$ \e@]\e& \e033[0m" \e
8868 reply-to-honour=ask-yes
8870 # When `p'rinting messages, show only these headers
8871 # (use `P'rint for all headers and `S'how for raw message)
8872 retain date from to cc subject
8874 # Some mailing lists
8875 mlist @xyz-editor.xyz$ @xyzf.xyz$
8876 mlsubscribe ^xfans@xfans.xyz$
8878 # A real life example of a very huge free mail provider
8881 set from="Your Name <youremail@domain>"
8882 # (The plain smtp:// proto is optional)
8883 set smtp=USER:PASS@smtp.gmXil.com smtp-use-starttls
8886 # Here is a pretty large one which does not allow sending mails
8887 # if there is a domain name mismatch on the SMTP protocol level,
8888 # which would bite us if the value of from does not match, e.g.,
8889 # for people who have a sXXXXeforge project and want to speak
8890 # with the mailing list under their project account (in from),
8891 # still sending the message through their normal mail provider
8894 set from="Your Name <youremail@domain>"
8895 set smtp=smtps://USER:PASS@smtp.yaXXex.ru:465 \e
8896 hostname=yaXXex.com smtp-hostname=
8899 # Create some new commands so that, e.g., `ls /tmp' will..
8910 ghost llS !ls -aFlrS
8913 # We don't support gpg(1) directly yet. But simple --clearsign'd
8914 # message parts can be dealt with as follows:
8917 set pipe-text/plain="@*#++=@\e
8918 < \e"${NAIL_FILENAME_TEMPORARY}\e" awk \e
8919 -v TMPFILE=\e"${NAIL_FILENAME_TEMPORARY}\e" '\e
8921 /^-----BEGIN PGP SIGNED MESSAGE-----/,/^$/ {\e
8924 print \e"--- GPG --verify ---\e";\e
8925 system(\e"gpg --verify \e" TMPFILE \e" 2>&1\e");\e
8926 print \e"--- GPG --verify ---\e";\e
8930 /^-----BEGIN PGP SIGNATURE-----/,\e
8931 /^-----END PGP SIGNATURE-----/ {\e
8941 !printf 'Key IDs to gpg --recv-keys: ';\e
8943 gpg --recv-keys ${keyids};
8949 When storing passwords in
8951 appropriate permissions should be set on this file with
8952 .Ql $ chmod 0600 \*(ur .
8955 is available user credentials can be stored in the central
8957 file instead; e.g., here is a different version of the example account
8958 that sets up SMTP and POP3:
8960 .Bd -literal -offset indent
8963 set from="Your Name <youremail@domain>"
8965 #set agent-shell-lookup="gpg -d .pass.gpg"
8967 set smtp=smtps://smtp.yXXXXx.ru:465 \e
8968 smtp-hostname= hostname=yXXXXx.com
8969 set pop3-keepalive=240 pop3-no-apop-pop.yXXXXx.ru
8970 ghost xp fi pop3s://pop.yXXXXx.ru
8979 .Bd -literal -offset indent
8980 machine *.yXXXXx.ru login USER password PASS
8985 .Va agent-shell-lookup
8986 is available things could be diversified further by using encrypted
8987 password storage: for this, don't specify
8991 file and instead uncomment the line that defines agent lookup in the
8994 above, then create the encrypted password storage file
8997 .Bd -literal -offset indent
9000 $ eval `gpg-agent --daemon \e
9001 --pinentry-program=/usr/bin/pinentry-curses \e
9002 --max-cache-ttl 99999 --default-cache-ttl 99999`
9006 This configuration should now work just fine (use the
9008 command line option for a(n almost) dry-run):
9011 .Dl $ echo text | \*(ua -vv -AXandeX -s Subject some@where
9014 .\" .Ss "Signed and encrypted messages with S/MIME" {{{
9015 .Ss "Signed and encrypted messages with S/MIME"
9017 \*(OP S/MIME provides two central mechanisms:
9018 message signing and message encryption.
9019 A signed message contains some data in addition to the regular text.
9020 The data can be used to verify that the message was sent using a valid
9021 certificate, that the sender's address in the message header matches
9022 that in the certificate, and that the message text has not been altered.
9023 Signing a message does not change its regular text;
9024 it can be read regardless of whether the recipient's software is able to
9028 It is thus usually possible to sign all outgoing messages if so desired.
9029 Encryption, in contrast, makes the message text invisible for all people
9030 except those who have access to the secret decryption key.
9031 To encrypt a message, the specific recipient's public encryption key
9033 It is therefore not possible to send encrypted mail to people unless their
9034 key has been retrieved from either previous communication or public key
9036 A message should always be signed before it is encrypted.
9037 Otherwise, it is still possible that the encrypted message text is
9041 A central concept to S/MIME is that of the certification authority (CA).
9042 A CA is a trusted institution that issues certificates.
9043 For each of these certificates it can be verified that it really
9044 originates from the CA, provided that the CA's own certificate is
9046 A set of CA certificates is usually delivered with OpenSSL and installed
9048 If you trust the source of your OpenSSL software installation,
9049 this offers reasonable security for S/MIME on the Internet.
9051 .Va ssl-no-default-ca
9055 .Va smime-ca-dir . )
9056 In general, a certificate cannot be more secure than the method its CA
9057 certificate has been retrieved with, though.
9058 Thus if you download a CA certificate from the Internet,
9059 you can only trust the messages you verify using that certificate as
9060 much as you trust the download process.
9063 The first thing you need for participating in S/MIME message exchange is
9064 your personal certificate, including a private key.
9065 The certificate contains public information, in particular your name and
9066 your email address(es), and the public key that is used by others to
9067 encrypt messages for you,
9068 and to verify signed messages they supposedly received from you.
9069 The certificate is included in each signed message you send.
9070 The private key must be kept secret.
9071 It is used to decrypt messages that were previously encrypted with your
9072 public key, and to sign messages.
9075 For personal use it is recommended that you get a S/MIME certificate
9076 from one of the major CAs on the Internet using your WWW browser.
9077 Many CAs offer such certificates for free.
9079 .Lk https://www.CAcert.org
9080 which issues client and server certificates to members of their
9081 community for free; their root certificate
9082 .Pf ( Lk https://\:www.cacert.org/\:certs/\:root.crt )
9083 is often not in the default set of trusted CA root certificates, though,
9084 which means you will have to download their root certificate separately
9085 and ensure it is part of our S/MIME certificate validation chain by
9088 or as a vivid member of the
9090 But let's take a step-by-step tour on how to setup S/MIME with
9091 a certificate from CAcert.org despite this situation!
9094 First of all you will have to become a member of the CAcert.org
9095 community, simply by registrating yourself via the web interface.
9096 Once you are, create and verify all email addresses you want to be able
9097 to create signed and encrypted messages for/with using the corresponding
9098 entries of the web interface.
9099 Now ready to create S/MIME certificates, so let's create a new
9100 .Dq client certificate ,
9101 ensure to include all email addresses that should be covered by the
9102 certificate in the following web form, and also to use your name as the
9106 Create a private key and a certificate request on your local computer
9107 (please see the manual pages of the used commands for more in-depth
9108 knowledge on what the used arguments etc. do):
9111 .Dl openssl req -nodes -newkey rsa:4096 -keyout key.pem -out creq.pem
9114 Afterwards copy-and-paste the content of
9116 into the certificate-request (CSR) field of the web form on the
9117 CAcert.org website (you may need to unfold some
9118 .Dq advanced options
9119 to see the corresponding text field).
9120 This last step will ensure that your private key (which never left your
9121 box) and the certificate belong together (through the public key that
9122 will find its way into the certificate via the certificate-request).
9123 You are now ready and can create your CAcert certified certificate.
9124 Download and store or copy-and-paste it as
9129 In order to use your new S/MIME setup you will have to create
9130 a combined private key/public key (certificate) file:
9133 .Dl cat key.pem pub.crt > ME@HERE.com.paired
9136 This is the file \*(UA will work with.
9137 If you have created your private key with a passphrase then \*(UA will
9138 ask you for it whenever a message is signed or decrypted.
9139 Set the following variables to henceforth use S/MIME (setting
9141 is of interest for verification only):
9143 .Bd -literal -offset indent
9144 set smime-ca-file=ALL-TRUSTED-ROOT-CERTS-HERE \e
9145 smime-sign-cert=ME@HERE.com.paired \e
9146 smime-sign-message-digest=SHA256 \e
9151 From each signed message you send, the recipient can fetch your
9152 certificate and use it to send encrypted mail back to you.
9153 Accordingly if somebody sends you a signed message, you can do the same,
9156 command to check the validity of the certificate.
9159 Variables of interest for S/MIME signing:
9163 .Va smime-crl-file ,
9164 .Va smime-no-default-ca ,
9166 .Va smime-sign-cert ,
9167 .Va smime-sign-include-certs
9169 .Va smime-sign-message-digest .
9172 After it has been verified save the certificate via
9174 and tell \*(UA that it should use it for encryption for further
9175 communication with that somebody:
9177 .Bd -literal -offset indent
9179 set smime-encrypt-USER@HOST=FILENAME \e
9180 smime-cipher-USER@HOST=AES256
9184 Additional variables of interest for S/MIME en- and decryption:
9187 .Va smime-encrypt-USER@HOST .
9190 You should carefully consider if you prefer to store encrypted messages
9192 If you do, anybody who has access to your mail folders can read them,
9193 but if you do not, you might be unable to read them yourself later if
9194 you happen to lose your private key.
9197 command saves messages in decrypted form, while the
9201 commands leave them encrypted.
9204 Note that neither S/MIME signing nor encryption applies to message
9205 subjects or other header fields yet.
9206 Thus they may not contain sensitive information for encrypted messages,
9207 and cannot be trusted even if the message content has been verified.
9208 When sending signed messages,
9209 it is recommended to repeat any important header information in the
9213 .\" .Ss "Using CRLs with S/MIME or SSL/TLS" {{{
9214 .Ss "Using CRLs with S/MIME or SSL/TLS"
9216 \*(OP Certification authorities (CAs) issue certificate revocation
9217 lists (CRLs) on a regular basis.
9218 These lists contain the serial numbers of certificates that have been
9219 declared invalid after they have been issued.
9220 Such usually happens because the private key for the certificate has
9222 because the owner of the certificate has left the organization that is
9223 mentioned in the certificate, etc.
9224 To seriously use S/MIME or SSL/TLS verification,
9225 an up-to-date CRL is required for each trusted CA.
9226 There is otherwise no method to distinguish between valid and
9227 invalidated certificates.
9228 \*(UA currently offers no mechanism to fetch CRLs, nor to access them on
9229 the Internet, so you have to retrieve them by some external mechanism.
9232 \*(UA accepts CRLs in PEM format only;
9233 CRLs in DER format must be converted, like, e.\|g.:
9236 .Dl $ openssl crl \-inform DER \-in crl.der \-out crl.pem
9239 To tell \*(UA about the CRLs, a directory that contains all CRL files
9240 (and no other files) must be created.
9245 variables, respectively, must then be set to point to that directory.
9246 After that, \*(UA requires a CRL to be present for each CA that is used
9247 to verify a certificate.
9250 .\" .Ss "Handling spam" {{{
9253 \*(OP \*(UA can make use of several spam interfaces for the purpose of
9254 identification of, and, in general, dealing with spam messages.
9255 A precondition of most commands in order to function is that the
9257 variable is set to one of the supported interfaces.
9258 Once messages have been identified as spam their (volatile)
9260 state can be prompted: the
9264 message specifications will address respective messages and their
9266 entries will be used when displaying the
9268 in the header display.
9273 rates the given messages and sets their
9276 If the spam interface offers spam scores those can also be displayed in
9277 the header display by including the
9287 will interact with the Bayesian filter of the chosen interface and learn
9288 the given messages as
9292 respectively; the last command can be used to cause
9294 of messages; it adheres to their current
9296 state and thus reverts previous teachings.
9301 will simply set and clear, respectively, the mentioned volatile
9303 message flag, without any interface interaction.
9310 .Va spam-interface Ns s
9314 require a running instance of the
9316 server in order to function, started with the option
9318 shall Bayesian filter learning be possible.
9320 only works via a local path-based
9322 socket, but otherwise the following will be equivalently fine:
9324 .Bd -literal -offset indent
9325 $ spamd -i localhost:2142 -i /tmp/.spamsock -d [-L] [-l]
9326 $ spamd --listen=localhost:2142 --listen=/tmp/.spamsock \e
9327 --daemonize [--local] [--allow-tell]
9331 Thereafter \*(UA can make use of these interfaces:
9333 .Bd -literal -offset indent
9334 $ \*(ua -Sspam-interface=spamd -Sspam-maxsize=500000 \e
9335 -Sspamd-socket=/tmp/.spamsock -Sspamd-user=
9337 $ \*(ua -Sspam-interface=spamc -Sspam-maxsize=500000 \e
9338 -Sspamc-command=/usr/local/bin/spamc \e
9339 -Sspamc-arguments="-U /tmp/.spamsock" -Sspamc-user=
9341 $ \*(ua -Sspam-interface=spamc -Sspam-maxsize=500000 \e
9342 -Sspamc-command=/usr/local/bin/spamc \e
9343 -Sspamc-arguments="-d localhost -p 2142" -Sspamc-user=
9347 Using the generic filter approach allows usage of programs like
9351 Here is an example for the former, requiring it to be accessible via
9354 .Bd -literal -offset indent
9355 $ \*(ua -Sspam-interface=filter -Sspam-maxsize=500000 \e
9356 -Sspamfilter-ham="bogofilter -n" \e
9357 -Sspamfilter-noham="bogofilter -N" \e
9358 -Sspamfilter-nospam="bogofilter -S" \e
9359 -Sspamfilter-rate="bogofilter -TTu 2>/dev/null" \e
9360 -Sspamfilter-spam="bogofilter -s" \e
9361 -Sspamfilter-rate-scanscore="1;^(.+)$"
9365 Because messages must exist on local storage in order to be scored (or
9366 used for Bayesian filter training), it is possibly a good idea to
9367 perform the local spam check last:
9369 .Bd -literal -offset indent
9370 define spamdelhook {
9372 spamset (header x-dcc-brand-metrics "bulk")
9373 # Server-side spamassassin(1)
9374 spamset (header x-spam-flag "YES")
9375 del :s # TODO we HAVE to be able to do `spamrate :u ! :sS'
9381 set folder-hook-FOLDER=spamdelhook
9385 See also the documentation for the variables
9386 .Va spam-interface , spam-maxsize ,
9387 .Va spamc-command , spamc-arguments , spamc-user ,
9388 .Va spamd-socket , spamd-user ,
9389 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
9392 .Va spamfilter-rate-scanscore .
9400 .\" .Ss "\*(UA shortly hangs on startup" {{{
9401 .Ss "\*(UA shortly hangs on startup"
9403 This can have two reasons, one is the necessity to wait for a file lock
9404 and can't be helped, the other being that \*(UA calls the function
9406 in order to query the nodename of the box (sometimes the real one is
9407 needed instead of the one represented by the internal variable
9409 You may have varying success by ensuring that the real hostname and
9413 or, more generally, that the name service is properly setup \(en
9416 return what you'd expect?
9417 Does this local hostname has a domain suffix?
9418 RFC 6762 standardized the link-local top-level domain
9422 .\" .Ss "I can't login to Google mail a.k.a. GMail" {{{
9423 .Ss "I can't login to Google mail a.k.a. GMail"
9425 Since 2014 some free service providers classify programs as
9427 unless they use a special authentification method (OAuth 2.0) which
9428 wasn't standardized for non-HTTP protocol authentication token query
9429 until August 2015 (RFC 7628).
9432 Different to Kerberos / GSSAPI, which is developed since the mid of the
9433 1980s, where a user can easily create a local authentication ticket for
9434 her- and himself with the locally installed
9436 program, that protocol has no such local part but instead requires
9437 a world-wide-web query to create or fetch a token; since there is no
9438 local cache this query has to be performed whenever \*(UA is invoked
9439 from the command line (in interactive sessions situation may differ).
9442 \*(UA doesn't support OAuth.
9443 Because of this it is necessary to declare \*(UA a
9445 (on the providers account web page) in order to read and send mail.
9446 However, it also seems possible to take the following steps instead:
9451 give the provider the number of a mobile phone,
9454 .Dq 2-Step Verification ,
9456 create an application specific password (16 characters), and
9458 use that special password instead of your real Google account password in
9459 S-nail (for more on that see the section
9460 .Sx "On URL syntax and credential lookup" ) .
9466 .\" .Sh "SEE ALSO" {{{
9484 .Xr spamassassin 1 ,
9511 M. Douglas McIlroy writes in his article
9512 .Dq A Research UNIX Reader: Annotated Excerpts \
9513 from the Programmer's Manual, 1971-1986
9516 command already appeared in First Edition
9520 .Bd -ragged -offset indent
9521 Electronic mail was there from the start.
9522 Never satisfied with its exact behavior, everybody touched it at one
9523 time or another: to assure the safety of simultaneous access, to improve
9524 privacy, to survive crashes, to exploit uucp, to screen out foreign
9525 freeloaders, or whatever.
9526 Not until v7 did the interface change (Thompson).
9527 Later, as mail became global in its reach, Dave Presotto took charge and
9528 brought order to communications with a grab-bag of external networks
9534 Mail was written in 1978 by Kurt Shoens and developed as part of the
9537 distribution until 1995.
9538 Mail has then seen further development in open source
9540 variants, noticeably by Christos Zoulas in
9542 Basing upon this Nail, later Heirloom Mailx, was developed by Gunnar
9543 Ritter in the years 2000 until 2008.
9544 Since 2012 S-nail is maintained by Steffen (Daode) Nurpmeso.
9545 This man page is derived from
9546 .Dq The Mail Reference Manual
9547 that was originally written by Kurt Shoens.
9554 .An "Christos Zoulas" ,
9555 .An "Gunnar Ritter" ,
9556 .An "Steffen Nurpmeso" Aq Mt s-nail-users@lists.sourceforge.net
9558 .Mt s-mailx@sdaoden.eu ) .
9564 The character set conversion uses and relies upon the
9567 Its functionality differs widely between the various system environments
9571 Limitations with POP3 mailboxes are:
9572 It is not possible to edit messages, they can only be copied and deleted.
9573 The line count for the header display is only appropriate if the entire
9574 message has been downloaded from the server.
9575 The status field of a message is maintained by the server between
9576 connections; some servers do not update it at all, and with a server
9579 command will not cause the message status to be reset.
9584 variable have no effect.
9585 It is not possible to rename or to remove POP3 mailboxes.
9592 is typed while a POP3 operation is in progress, \*(UA will wait
9593 until the operation can be safely aborted, and will then return to the
9594 command loop and print the prompt again.
9597 is typed while \*(UA is waiting for the operation to complete, the
9598 operation itself will be cancelled.
9599 In this case, data that has not been fetched yet will have to be fetched
9600 before the next command can be performed.
9601 If the cancelled operation was using an SSL/TLS encrypted channel,
9602 an error in the SSL transport will very likely result and render the
9603 connection unusable.
9606 As \*(UA is a mail user agent, it provides only basic SMTP services.
9607 If it fails to contact its upstream SMTP server, it will not make
9608 further attempts to transfer the message at a later time,
9609 and it does not leave other information about this condition than an
9610 error message on the terminal and an entry in
9612 This is usually not a problem if the SMTP server is located in the same
9613 local network as the computer on which \*(UA is run.
9614 However, care should be taken when using a remote server of an ISP;
9615 it might be better to set up a local SMTP server then which just acts as
9619 \*(UA immediately contacts the SMTP server (or
9621 It would not make much sense for \*(UA to defer outgoing mail since SMTP
9622 servers usually provide much more elaborated delay handling than \*(UA
9623 could perform as a client.
9631 from the distribution or the repository.
9633 After deleting some message of a POP3 mailbox the header summary falsely
9634 claims that there are no messages to display, you need to perform
9635 a scroll or dot movement to restore proper state.
9637 In threaded display a power user may encounter crashes very
9638 occasionally (this is may and very).