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
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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
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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 yet complete compatibility won't be possible.
129 To choose upward compatible behaviour, please set the internal variable
131 Anything which will vanish in v15.0 is tagged \*(OB, and using
133 will print warnings for many use cases of obsolete features.
137 \*(UA is a mail processing system with a command syntax reminiscent of
139 with lines replaced by messages.
140 It is intended to provide the functionality of the POSIX
142 command, but is MIME capable and optionally offers extensions for
143 line editing, S/MIME, SMTP and POP3 among others.
144 It is usable as a mail batch language.
146 .\" .Ss "Options" {{{
149 .Bl -tag -width ".Fl _ Ar _ccount"
152 Explicitly control which of the
154 shall be loaded: if the letter
156 is (case-insensitively) part of the
160 is loaded, likewise the letter
162 controls loading of the user's personal
164 file, whereas the letters
168 explicitly forbid loading of any resource files.
169 This option should be used by scripts: to avoid environmental noise they
172 from any configuration files and create a script-local environment,
173 explicitly setting any desired variable via
175 This option overrides
182 command (see below) for
184 after the startup files have been read.
188 Attach the given file to the message.
189 The same filename conventions as described in the section
191 apply: shell word expansion is restricted to the tilde
196 not be accessible but contain a
198 character, then anything after the
200 is assumed to specify the input character set and anything before
202 the filename: this is the only option to specify the input character set
203 (and don't perform any character set conversion) for text attachments
204 from the command line, not using the
206 tilde escape command.
210 Make standard input and standard output line-buffered.
214 Send a blind carbon copy to
216 Can be used multiple times, but it is also possible to give
217 a comma-separated list of receivers in a single argument, proper shell
218 quoting provided, e.g.,
219 .Ql -b """qrec1 , rec2,rec3, Ex <am@ple>""" .
221 .Sx "On sending mail, and non-interactive mode" .
225 Send carbon copies to the given receiver(s).
226 Can be used multiple times.
232 variable which enables debug messages and disables message delivery,
233 among others; effectively turns almost any operation into a dry-run.
239 variable and thus discard messages with an empty message part body.
240 This is useful for sending messages from scripts.
244 Just check if mail is present (in the specified or system mailbox).
245 If yes, return an exit status of zero, a non-zero value otherwise.
246 To restrict the set of mails to consider in this evaluation a message
247 specification can be added with the option
252 Save the message to send in a file named after the local part of the
253 first recipient's address (instead of in
258 Read in the contents of the user's
260 (or the specified file) for processing;
261 when \*(UA is quit, it writes undeleted messages back to this file
265 Some special conventions are recognized for the string
267 which are documented for the
272 is not a direct argument to the flag
274 but is instead taken from the command line after option processing has
278 that starts with a hyphen, prefix it with a (relative) path, as in
279 .Ql ./-hyphenbox.mbox .
283 Display a summary of the
285 of all messages in the specified or system mailbox and exit.
286 A configurable summary view is available via the
292 Show a short usage summary.
293 Because of widespread use a
295 argument will have the same effect.
301 variable to ignore tty interrupt signals.
304 .It Fl L Ar spec-list
305 Display a summary of all
307 of only those messages in the specified or system mailbox that match the
312 .Sx "Specifying messages"
319 option has been given in addition no header summary is produced,
320 but \*(UA will instead indicate via its exit status wether
326 note that any verbose output is suppressed in this mode and must instead
327 be enabled explicitly (e.g., by using the option
334 variable and thus inhibit initial display of message headers when
335 reading mail or editing a mail folder.
339 Standard flag that inhibits reading the system wide
344 allows more control over the startup sequence; also see
345 .Sx "Resource files" .
349 Initialize the message body with the contents of the specified file,
350 which may be standard input
352 only in non-interactive context.
353 May be given in send mode only.
357 Any folder opened will be in read-only mode.
363 is a valid address then it specifies the envelope sender address to be
366 when a message is send.
369 include a user name, comments etc., then the components will be
370 separated and the name part will be passed to the MTA individually via
374 will also be assigned to the
376 variable, just as if additionally
378 had been specified (therefore affecting SMTP data transfer, too).
380 If instead an empty string is passed as
382 then the content of the variable
384 will be evaluated and used for this purpose whenever the MTA is
386 Note that \*(UA by default, without
388 that is, neither passes
392 flags to the MTA by itself.
395 .It Fl S Ar variable Ns Op = Ns value
396 Sets the internal option
398 and, in case of a value option, assigns
401 Even though variables set via
403 may be overwritten from within resource files,
404 the command line setting will be reestablished after all resource files
409 Specify the subject of the to-be-sent message.
413 The message given (on standard input) is expected to contain, separated
414 from the message body with an empty line, a message header with
419 fields giving its recipients, which will be added to those given on the
421 If a message subject is specified via
423 then it'll be used in favour of one given on the command line.
432 Note you can also specify
436 and the envelope address possibly specified with the option
439 The following, which are normally created automatically based
440 upon the message context, can also be specified:
445 .Ql Mail-Followup-To:
446 (special address massage will however still occur for the latter).
447 In fact custom header fields may also be used, the content of which
448 is passed through unchanged.
452 can be embedded, too.
456 Read the system mailbox of
458 (appropriate privileges presumed), and
461 in some aspects, e.g. in respect to
470 Show \*(UA's version and exit.
476 option enables display of some informational context messages.
477 Using it twice increases the level of verbosity.
483 to the list of commands to be executed before normal operation starts.
487 .Va batch-exit-on-error ;
488 the only possibility to execute commands in non-interactive mode when
489 reading startup files is actively prohibited.
495 even if not in interactive mode.
500 In batch mode the full set of commands is available, just like in
501 interactive mode, and diverse variable settings and internal states are
502 adjusted for batch necessities, e.g., it sets
513 It also enables processing of
514 .Sx "TILDE ESCAPES" .
515 E.g., the following should send an email message to
517 .Bd -literal -offset indent
518 $ LC_ALL=C printf 'm bob\en~s ubject\enText\en~.\enx\en' | \e
519 LC_ALL=C \*(ua -:/ -d#
524 This flag forces termination of option processing in order to prevent
527 It also forcefully puts \*(UA into send mode, see
528 .Sx "On sending mail, and non-interactive mode" .
532 In the above list of supported command line options,
536 are implemented by means of setting the respective option, as via
539 .Op Ar mta-option ...
541 arguments that are given at the end of the command line after a
543 separator will be passed through to the mail-transfer-agent (MTA) and
544 persist for an entire (interactive) session \(en if the setting of
546 allows their recognition;
547 MTA arguments can also be specified in the variable
548 .Va sendmail-arguments ;
549 find MTA interaction described in more detail in the documentation of
551 MTA arguments are ignored when mail is send via SMTP data transfer.
554 .\" .Ss "A starter" {{{
557 \*(UA is a direct descendant of
559 Mail, a successor of the Research
562 .Dq was there from the start
567 Mail reference manual begins with the following words:
569 .Bd -ragged -offset indent
570 Mail provides a simple and friendly environment for sending and
572 It divides incoming mail into its constituent messages and allows the
573 user to deal with them in any order.
574 In addition, it provides a set of
576 -like commands for manipulating messages and sending mail.
577 Mail offers the user simple editing capabilities to ease the composition
578 of outgoing messages, as well as providing the ability to define and
579 send to names which address groups of users.
583 \*(UA is thus the user side of the
585 mail system, whereas the system side (mail-transfer-agent, MTA) was
586 traditionally taken by
592 are often used for this purpose instead.
593 If the \*(OPal SMTP is included in the
595 of \*(UA then the system side is not a mandatory precondition for mail
599 Because \*(UA strives for compliance with POSIX
601 it is likely that some configuration settings have to be adjusted before
602 using it is a smooth experience.
605 file already bends those standard settings a bit towards more user
606 friendliness and safety, e.g., it sets the
610 variables in order to suppress the automatic moving of messages to
612 that would otherwise occur (see
613 .Sx "Message states" )
616 to not remove empty files in order not to mangle file permissions when
617 files eventually get recreated.
620 option so that by default file grouping (via the
622 prefix as documented also for
627 contains some further suggestions.
630 .\" .Ss "On sending mail, and non-interactive mode" {{{
631 .Ss "On sending mail, and non-interactive mode"
633 To send a message to one or more people, using a local
634 mail-transfer-agent (MTA; the executable path can be set via
636 or the \*(OPal builtin SMTP (set and see the variable
638 transport to actually deliver the generated mail message, \*(UA can be
639 invoked with arguments which are the names of people to whom the mail
642 .Bd -literal -offset indent
643 $ \*(ua -s Subject -a attachm.ent bill@host1 'Bob <bob@host2>'
644 # But... try it in an isolated dry-run mode first
645 $ LC_ALL=C \*(ua -:/ -d -vv -Sfrom="me <he@exam.ple>" \e
646 -b bcc@exam.ple -c cc@exam.ple \e
647 -s Subject -. "(Lovely) Bob <bob@host2>"
651 The command line options
655 can be used to add (blind) carbon copy receivers.
656 Almost always lists of addresses can be given where an address is
658 whereas comma-separated lists should be given, e.g.,
659 .Ql -c """r1@exam.ple , r2@exam.ple,r3@exam.ple""" ,
660 that very example could also be given as the whitespace-separated list
661 .Ql -c """r1@exam.ple r2@exam.ple r3@exam.ple""" ,
662 but which for obvious reasons would not work for
663 .Ql -c """R1 <r1@exam.ple>, R2 (heh!) <r2@exam.ple>""" .
666 The user is then expected to type in the message contents.
667 In this compose mode \*(UA treats lines beginning with the character
669 special \(en these are so-called
671 which can be used to read in files, process shell commands, add and edit
672 attachments and more; e.g., the tilde escape
674 will start the text editor to revise the message in it's current state,
676 allows editing of the message recipients and
678 gives an overview of available tilde escapes.
681 at the beginning of an empty line leaves compose mode and causes the
682 message to be sent, whereas typing
685 twice will abort the current letter (saving its contents in the file
693 A number of variables can be used to alter default behavior; e.g.,
698 will automatically startup a text editor when compose mode is entered,
700 will cause the user to be prompted actively for carbon-copy recipients
703 option will allow leaving compose mode by writing a line consisting
708 Very important, though, is to define which
710 may be used when sending messages, usually by setting the option
713 having read the section
714 .Sx "The mime.types files"
715 to understand how the MIME-type of outgoing attachments is classified
716 and the knowledge that messages are sent asynchronously unless
718 is set: only with it MTA delivery errors will be recognizable.
723 is often necessary (e.g., in conjunction with
725 or desirable, you may want to do some dry-run tests before you go.
726 Saving a copy of the sent messages in a
728 may also be desirable \(en as for most mailbox file targets some
729 special conventions are recognized, see the
731 command for more on that.
733 .Sx "On URL syntax and credential lookup"
734 will spread some light on the
736 variable chains as well as on using URLs for accessing protocol-specific
741 contains an example configuration for sending messages via some of the
742 well-known public mail providers;
743 note it also gives a compact overview on how to setup a secure SSL/TLS
747 Message recipients (as specified on the command line or defined in
752 may not only be email addressees but can also be names of mailboxes and
753 even complete shell command pipe specifications.
754 Proper (shell) quoting is necessary, e.g., to embed whitespace characters.
755 (Recall that \*(UA deals with mail standards, therefore those define the
756 rules with which content is interpreted.)
759 is not set then only network addresses (see
761 for a description of mail addresses) and plain user names (including MTA
762 aliases) may be used, other types will be filtered out, giving a warning
765 .\" When changing any of the following adjust any RECIPIENTADDRSPEC;
766 .\" grep the latter for the complete picture
770 is set then extended recipient addresses will optionally be accepted:
771 Any name which starts with a vertical bar
773 character specifies a command pipe \(en the command string following the
775 is executed and the message is sent to its standard input;
776 Likewise, any name that starts with the character slash
778 or the character sequence dot slash
780 is treated as a file, regardless of the remaining content.
781 Any other name which contains an at sign
783 character is treated as a network address;
784 Any other name which starts with a plus sign
786 character specifies a mailbox name;
787 Any other name which contains a slash
789 character but no exclamation mark
793 character before also specifies a mailbox name;
794 What remains is treated as a network address.
796 .Bd -literal -offset indent
797 $ echo bla | \*(ua -Sexpandaddr -s test ./mbox.mbox
798 $ echo bla | \*(ua -Sexpandaddr -s test '|cat >> ./mbox.mbox'
799 $ echo safe | LC_ALL=C \e
800 \*(ua -:/ -Sv15-compat -Ssendwait -Snosave \e
801 -Sexpandaddr=fail,-all,+addr -s test \e
806 It is possible to create personal distribution lists via the
808 command, so that, for instance, the user can send mail to
810 and have it go to a group of people:
813 .Dl alias cohorts bill jkf mark kridle@ucbcory ~/mail/cohorts.mbox
816 Please note that this mechanism has nothing in common with the system
817 wide aliases that may be used by the local MTA (mail-transfer-agent),
818 which are subject to the
822 and are often tracked in a file
828 Personal aliases will be expanded by \*(UA before the message is sent,
829 and are thus a convenient alternative to specifying each addressee by
833 To avoid environmental noise scripts should
835 \*(UA from any configuration files and create a script-local
836 environment, ideally with the command line options
838 to disable any configuration file in conjunction with repititions of
840 to specify variables:
842 .Bd -literal -offset indent
843 $ env LC_ALL=C password=NOTSECRET \e
844 \*(ua -:/ -Sv15-compat -Ssendwait -Snosave \e
845 -Sexpandaddr=fail,-all,+addr \e
846 -S 'smtp=smtps://mylogin@some.host:465' -Ssmtp-auth=login \e
847 -S 'from=scriptreply@domain' \e
848 -s 'subject' -a attachment_file \e
849 -. "Recipient 1 <recipient1@domain>" recipient2@domain \e
854 In interactive mode, which is introduced in the next section, messages
855 can be sent by calling the
857 command with a list of recipient addresses \(em the semantics are
858 completely identical to non-interactive message sending, except that
859 it is likely necessary to separate recipient lists with commas:
861 .Bd -literal -offset indent
862 $ \*(ua -d -Squiet -Semptystart
863 "/var/spool/mail/user": 0 messages
864 ? mail "Recipient 1 <recipient1@domain>", recipient2@domain
865 ? # Will do the right thing (tm)
866 ? m recipient1@domain recipient2@domain
870 .\" .Ss "On reading mail, and interactive mode" {{{
871 .Ss "On reading mail, and interactive mode"
873 When invoked without addressees \*(UA enters interactive mode in which
875 When used like that the user's system mailbox (see the command
877 for an in-depth description of the different mailbox types that exist)
878 is read in and a one line header of each message therein is displayed.
879 The visual style of this summary of
881 can be adjusted through the variable
883 and the possible sorting criterion via
885 If the initially opened mailbox is empty \*(UA will instead exit
886 immediately (after displaying a message) unless the variable
895 will give a listing of all available commands and
897 will give a summary of some common ones.
898 If the \*(OPal documentation strings are available one can type
900 and see the actual expansion of
902 and what it's purpose is, i.e., commands can be abbreviated
903 (note that POSIX defines some abbreviations, so that the alphabetical
904 order of commands doesn't necessarily relate to the abbreviations; it is
905 possible to define overwrites with the
910 Messages are given numbers (starting at 1) which uniquely identify
911 messages; the current message \(en the
913 \(en will either be the first new message, or the first unread message,
914 or the first message of the mailbox; the option
916 will instead cause usage of the last message for this purpose.
921 ful of header summaries containing the
925 will display only the summaries of the given messages, defaulting to the
929 Messages can be displayed on the user's terminal with the
933 By default the current message
935 is displayed, but like with many other commands it is possible to give
936 a fancy message specification (see
937 .Sx "Specifying messages" ) ,
940 will display all unread messages,
945 will type the messages 1 and 5,
947 will type the messages 1 through 5, and
951 will display the last and the next message, respectively.
954 (a more substantial alias of the standard command
956 will display a header summary of the given message specification list
957 instead of their content, e.g., the following will search for subjects:
960 .Dl ? from """@Some subject to search for"""
963 In the default setup all header fields of a message will be displayed,
964 but this can be changed: either by blacklisting a list of fields via
966 or by whitelisting only a given list with the
969 .Ql Ic \:retain Ns \0date from to cc subject .
970 In order to display all header fields of a message regardless of
971 currently active ignore or retain lists, use the command
975 controls wether and when \*(UA will use the configured
977 for display instead of directly writing to the user terminal
978 (generally speaking).
979 Note that historically the global
981 not only adjusts the list of displayed headers, but also sets
985 Dependent upon the configuration a
986 .Sx "Command line editor"
987 aims at making user experience with the many
990 When reading the system mailbox or when
994 specified a mailbox explicitly prefixed with the special
996 modifier (propagating the mailbox to a primary one) then messages which
997 have been read will be moved to a secondary mailbox, the user's
999 file, automatically when the mailbox is left, either by changing the
1000 active mailbox or by quitting \*(UA (also see
1001 .Sx "Message states" )
1002 \(en this automatic moving from a system or primary to the secondary
1003 mailbox is not performed when the variable
1008 After examining a message the user can also
1012 to the sender and all recipients or
1014 exclusively to the sender(s).
1015 Messages can also be
1017 ed (shorter alias is
1019 Note that when replying to or forwarding a message recipient addresses
1020 will be stripped from comments and names unless the option
1023 Deletion causes \*(UA to forget about the message;
1024 This is not irreversible, though, one can
1026 the message by giving its number,
1027 or the \*(UA session can be ended by giving the
1032 To end a mail processing session one may either issue
1034 to cause a full program exit, which possibly includes
1035 automatic moving of read messages to
1037 as well as updating the \*(OPal command line editor history file,
1040 instead in order to prevent any of these actions.
1043 .\" .Ss "HTML mail and MIME attachments" {{{
1044 .Ss "HTML mail and MIME attachments"
1046 Messages which are HTML-only get more and more common and of course many
1047 messages come bundled with a bouquet of MIME attachments.
1048 Whereas \*(UA \*(OPally supports a simple HTML-to-text converter to deal
1049 with HTML messages (see
1050 .Sx "The mime.types files" ) ,
1051 it normally can't deal with any of these itself, but instead programs
1052 need to become registered to deal with specific MIME types or file
1054 These programs may either prepare plain text versions of their input
1055 in order to enable \*(UA to display the content on the terminal,
1056 or display the content themselves, for example in a graphical window.
1059 To install an external handler program for a specific MIME type set an
1061 .Va pipe-TYPE/SUBTYPE
1062 variable; to instead define a handler for a specific file extension set
1065 variable \(en these handlers take precedence.
1066 \*(OPally \*(UA supports mail user agent configuration as defined in
1067 RFC 1524; this mechanism, documented in the section
1068 .Sx "The Mailcap files" ,
1069 will be queried for display or quote handlers if none of the former two
1070 .\" TODO v15-compat "will be" -> "is"
1071 did; it will be the sole source for handlers of other purpose.
1072 A last source for handlers may be the MIME type definition itself, if
1073 the \*(UA specific type-marker extension was used when defining the type
1076 (Many of the builtin MIME types do so by default.)
1080 .Va mime-counter-evidence
1081 can be set to improve dealing with faulty MIME part declarations as are
1082 often seen in real-life messages.
1083 E.g., to display a HTML message inline (that is, converted to a more
1084 fancy plain text representation than the builtin converter is capable to
1085 produce) with either of the text-mode browsers
1089 teach \*(UA about MathML documents and make it display them as plain
1090 text, and to open PDF attachments in an external PDF viewer,
1091 asynchronously and with some other magic attached:
1093 .Bd -literal -offset indent
1094 if $features !@ HTML-FILTER
1095 #set pipe-text/html="elinks -force-html -dump 1"
1096 set pipe-text/html="lynx -stdin -dump -force_html"
1097 # Display HTML as plain text instead
1098 #set pipe-text/html=@
1100 mimetype '@ application/mathml+xml mathml'
1101 set pipe-application/pdf="@&=@ \e
1102 trap \e"rm -f \e\e\e"${NAIL_FILENAME_TEMPORARY}\e\e\e"\e" EXIT;\e
1103 trap \e"trap \e\e\e"\e\e\e" INT QUIT TERM; exit 1\e" \e INT QUIT TERM;\e
1104 xpdf \e"${NAIL_FILENAME_TEMPORARY}\e""
1108 Note: special care must be taken when using such commands as mail
1109 viruses may be distributed by this method: if messages of type
1110 .Ql application/x-sh
1111 or files with the extension
1113 were blindly filtered through the shell, for example, a message sender
1114 could easily execute arbitrary code on the system \*(UA is running on.
1115 For more on MIME, also in respect to sending of messages, see the
1117 .Sx "The mime.types files" ,
1118 .Sx "The Mailcap files"
1123 .\" .Ss "Mailing lists" {{{
1126 \*(UA offers some support to ease handling of mailing lists.
1129 promotes all given arguments to known mailing lists, and
1131 sets their subscription attribute, creating them first as necessary.
1136 automatically, but only resets the subscription attribute.)
1137 Using the commands without arguments will show (a subset of) all
1138 currently defined mailing lists.
1143 can be used to mark out messages with configured list addresses
1144 in the header display.
1147 \*(OPally mailing lists may also be specified as (extended) regular
1148 expressions, which allows matching of many addresses with a single
1150 However, all fully qualified list addresses are matched via a fast
1151 dictionary, whereas expressions are placed in (a) list(s) which is
1152 (are) matched sequentially.
1154 .Bd -literal -offset indent
1155 set followup-to followup-to-honour=ask-yes reply-to-honour=ask-yes
1156 mlist a1@b1.c1 a2@b2.c2 .*@lists.c3$
1157 mlsubscribe a4@b4.c4 exact@lists.c3
1162 .Va followup-to-honour
1164 .Ql Mail-\:Followup-\:To:
1165 header is honoured when the message is being replied to (via
1171 controls wether this header is created when sending mails; it will be
1172 created automatically for a couple of reasons, too, like when the
1174 .Dq mailing list specific
1179 is used to respond to a message with its
1180 .Ql Mail-Followup-To:
1184 A difference in between the handling of known and subscribed lists is
1185 that the address of the sender is usually not part of a generated
1186 .Ql Mail-Followup-To:
1187 when addressing the latter, whereas it is for the former kind of lists.
1188 Usually because there are exceptions: say, if multiple lists are
1189 addressed and not all of them are subscribed lists.
1191 For convenience \*(UA will, temporarily, automatically add a list
1192 address that is presented in the
1194 header of a message that is being responded to to the list of known
1196 Shall that header have existed \*(UA will instead, dependend on the
1198 .Va reply-to-honour ,
1201 for this purpose in order to accept a list administrators' wish that
1202 is supposed to have been manifested like that (but only if it provides
1203 a single address which resides on the same domain as what is stated in
1207 .\" .Ss "Resource files" {{{
1208 .Ss "Resource files"
1210 Upon startup \*(UA reads in several resource files:
1212 .Bl -tag -width ".It Pa _AIL_EXTRA_R_"
1215 System wide initialization file.
1216 Reading of this file can be suppressed, either by using the
1220 command line options, or by setting the environment variable
1221 .Ev NAIL_NO_SYSTEM_RC .
1225 File giving initial commands.
1226 A different file can be chosen by setting the environment variable
1228 Reading of this file can be suppressed with the
1230 command line option.
1232 .It Va NAIL_EXTRA_RC
1233 Can be used to define an optional startup file to be read after all
1234 other resource files.
1235 It can be used to specify settings that are not understood by other
1237 implementations, for example.
1238 This variable is only honoured when defined in a resource file.
1242 The content of these files is interpreted as follows:
1245 .Bl -bullet -compact
1247 A lines' leading whitespace is removed.
1249 Empty lines are ignored.
1251 Any other line is interpreted as a command.
1252 It may be spread over multiple input lines if the newline character is
1254 by placing a backslash character
1256 as the last character of the line; whereas any leading whitespace of
1257 follow lines is ignored, trailing whitespace before a escaped newline
1258 remains in the input.
1260 If the line (content) starts with the number sign
1262 then it is a comment-command \(en a real command! \(en and also ignored.
1263 This command is the only form of comment that is understood.
1269 .Bd -literal -offset indent
1270 # This line is a comment command. And y\e
1271 es, it is really continued here.
1278 .\" .Ss "Character sets" {{{
1279 .Ss "Character sets"
1281 \*(OP \*(UA detects the character set of the terminal by using
1282 mechanisms that are controlled by the
1287 should give an overview); the \*(UA internal variable
1289 will be set to the detected terminal character set accordingly
1290 and will thus show up in the output of the commands
1296 However, a user supplied
1298 value is not overwritten by this detection mechanism: this
1300 must be used if the detection doesn't work properly,
1301 and it may be used to adjust the name of the locale character set.
1302 E.g., on BSD systems one may use a locale with the character set
1303 ISO8859-1, which is not a valid name for this character set; to be on
1304 the safe side, one may set
1306 to the correct name, which is ISO-8859-1.
1309 Note that changing the value doesn't mean much beside that,
1310 since several aspects of the real character set are implied by the
1311 locale environment of the system,
1312 and that stays unaffected by the content of an overwritten
1315 (This is mostly an issue when interactively using \*(UA, though.
1316 It is actually possible to send mail in a completely
1318 locale environment, an option that \*(UA's test-suite uses excessively.)
1321 If no character set conversion capabilities have been compiled into
1324 doesn't include the term
1328 will be the only supported character set,
1329 it is simply assumed that it can be used to exchange 8-bit messages,
1330 and the rest of this section does not apply;
1331 it may however still be necessary to explicitly set it if automatic
1332 detection fails, since in that case it defaults to the mentioned
1333 .\" (Keep in SYNC: ./nail.1:"Character sets", ./nail.h:CHARSET_*!)
1337 When reading messages, their text is converted into
1339 as necessary in order to display them on the users terminal.
1340 Unprintable characters and invalid byte sequences are detected
1341 and replaced by proper substitution characters (unless the variable
1343 was set once \*(UA was started).
1345 .Va charset-unknown-8bit
1346 to deal with another hairy aspect of message interpretation.
1349 When sending messages all their parts and attachments are classified.
1350 Whereas no character set conversion is performed on those parts which
1351 appear to be binary data,
1352 the character set being used must be declared within the MIME header of
1353 an outgoing text part if it contains characters that do not conform to
1354 the set of characters that are allowed by the email standards.
1355 Permissible values for character sets can be declared using the
1359 which defines a catch-all last-resort fallback character set that is
1360 implicitly appended to the list of character-sets in
1364 When replying to a message and the variable
1365 .Va reply-in-same-charset
1366 is set then the character set of the message being replied to is tried
1368 And it is also possible to make \*(UA work even more closely related to
1369 the current locale setting automatically by using the variable
1370 .Va sendcharsets-else-ttycharset ,
1371 please see there for more information.
1374 All the specified character sets are tried in order unless the
1375 conversion of the part or attachment succeeds.
1376 If none of the tried (8-bit) character sets is capable to represent the
1377 content of the part or attachment,
1378 then the message will not be sent and its text will optionally be
1382 In general, if the message
1383 .Dq Cannot convert from a to b
1384 appears, either some characters are not appropriate for the currently
1385 selected (terminal) character set,
1386 or the needed conversion is not supported by the system.
1387 In the first case, it is necessary to set an appropriate
1389 locale and/or the variable
1393 The best results are usually achieved when \*(UA is run in a UTF-8
1394 locale on a UTF-8 capable terminal, in which case the full Unicode
1395 spectrum of characters is available.
1396 In this setup characters from various countries can be displayed,
1397 while it is still possible to use more simple character sets for sending
1398 to retain maximum compatibility with older mail clients.
1401 On the other hand the POSIX standard defines a locale-independent 7-bit
1402 .Dq portable character set
1403 that should be used when overall portability is an issue, the even more
1404 restricted subset named
1405 .Dq portable filename character set
1406 consisting of A-Z, a-z, 0-9, period
1415 .\" .Ss "Message states" {{{
1416 .Ss "Message states"
1418 \*(UA differentiates in between several different message states;
1419 the current state will be reflected in header summary displays if
1421 is configured to do so (via the internal variable
1423 and messages can also be selected and be acted upon depending on their
1425 .Sx "Specifying messages" ) .
1426 When operating on the system mailbox or in primary mailboxes opened with
1431 special actions, like the automatic moving of messages to the secondary
1433 mailbox may be applied when the mailbox is left (also implicitly via
1434 a successful exit of \*(UA, but not if the special command
1436 is used) \(en however, because this may be irritating to users which
1439 mail-user-agents, the default global
1445 variables in order to suppress this behaviour.
1447 .Bl -tag -width ".It Ql _reserved"
1449 Message has neither been viewed nor moved to any other state.
1450 Such messages are retained even in the system mailbox.
1453 Message has neither been viewed nor moved to any other state, but the
1454 message was present already when the mailbox has been opened last:
1455 Such messages are retained even in the system mailbox.
1458 The message has been processed by one of the following commands:
1478 commands may also cause the next message to be marked as read, depending
1484 command is used, messages that are in the system mailbox or in mailboxes
1485 which were opened with the special
1489 state when the mailbox is left will be saved in
1496 The message has been processed by one of the following commands:
1502 can be used to access such messages.
1505 The message has been processed by a
1507 command and it will be retained in its current location.
1510 The message has been processed by one of the following commands:
1516 command is used, messages that are in the system mailbox or in mailboxes
1517 which were opened with the special
1521 state when the mailbox is left will be deleted; they will be saved in
1529 .\" .Ss "Specifying messages" {{{
1530 .Ss "Specifying messages"
1537 can be given a list of message numbers as arguments to apply to a number
1538 of messages at once.
1541 deletes messages 1 and 2,
1544 will delete the messages 1 through 5.
1545 In sorted or threaded mode (see the
1549 will delete the messages that are located between (and including)
1550 messages 1 through 5 in the sorted/threaded order, as shown in the
1553 Multiple colon modifiers can be joined into one, e.g.,
1555 The following special message names exist:
1557 .Bl -tag -width ".It Ar _n_u"
1563 All old messages (any not in state
1588 All answered messages
1593 All messages marked as draft.
1595 \*(OP All messages classified as spam.
1597 \*(OP All messages with unsure spam classification.
1599 The current message, the so-called
1602 The message that was previously the current message.
1604 The parent message of the current message,
1605 that is the message with the Message-ID given in the
1607 field or the last entry of the
1609 field of the current message.
1611 The next previous undeleted message,
1612 or the next previous deleted message for the
1615 In sorted/threaded mode,
1616 the next previous such message in the sorted/threaded order.
1618 The next undeleted message,
1619 or the next deleted message for the
1622 In sorted/threaded mode,
1623 the next such message in the sorted/threaded order.
1625 The first undeleted message,
1626 or the first deleted message for the
1629 In sorted/threaded mode,
1630 the first such message in the sorted/threaded order.
1633 In sorted/threaded mode,
1634 the last message in the sorted/threaded order.
1638 selects the message addressed with
1642 is any other message specification,
1643 and all messages from the thread that begins at it.
1644 Otherwise it is identical to
1649 the thread beginning with the current message is selected.
1654 All messages that were included in the message list for the previous
1657 .It Ar / Ns Ar string
1658 All messages that contain
1660 in the subject field (case ignored).
1667 the string from the previous specification of that type is used again.
1669 .It Xo Op Ar @ Ns Ar name-list Ns
1672 All messages that contain the given case-insensitive search
1674 ession; if the \*(OPal regular expression (see
1676 support is available
1678 will be interpreted as (an extended) one if any of the
1680 (extended) regular expression characters is seen.
1682 .Ar @ Ns Ar name-list
1683 part is missing, the search is restricted to the subject field body,
1686 specifies a comma-separated list of header fields to search, as in
1688 .Dl '@to,from,cc@Someone i ought to know'
1690 In order to search for a string that includes a
1692 (commercial at) character the
1694 is effectively non-optional, but may be given as the empty string.
1695 Some special header fields may be abbreviated:
1709 respectively and case-insensitively.
1714 can be used to search in (all of) the header(s) of the message, and the
1723 can be used to perform full text searches \(en whereas the former
1724 searches only the body, the latter also searches the message header.
1726 This message specification performs full text comparison, but even with
1727 regular expression support it is almost impossible to write a search
1728 expression that savely matches only a specific address domain.
1729 To request that the content of the header is treated as a list of
1730 addresses, and to strip those down to the plain email address which the
1731 search expression is to be matched against, prefix the header name
1732 (abbreviation) with a tilde
1735 .Dl @~f@@a\e.safe\e.domain\e.match$
1739 .Dq any substring matches
1742 header, which will match addresses (too) even if
1744 is set (and POSIX says
1745 .Dq any address as shown in a header summary shall be matchable in this form ) ;
1748 variable is set, only the local part of the address is evaluated
1749 for the comparison, not ignoring case, and the setting of
1751 is completely ignored.
1752 For finer control and match boundaries use the
1754 search expression; the \*(OPal IMAP-style
1756 expression can also be used if substring matches are desired.
1760 \*(OP IMAP-style SEARCH expressions may also be used.
1761 This addressing mode is available with all types of folders;
1762 \*(UA will perform the search locally as necessary.
1763 Strings must be enclosed by double quotes
1765 in their entirety if they contain white space or parentheses;
1766 within the quotes, only backslash
1768 is recognized as an escape character.
1769 All string searches are case-insensitive.
1770 When the description indicates that the
1772 representation of an address field is used,
1773 this means that the search string is checked against both a list
1776 .Bd -literal -offset indent
1777 (\*qname\*q \*qsource\*q \*qlocal-part\*q \*qdomain-part\*q)
1782 and the addresses without real names from the respective header field.
1783 These search expressions can be nested using parentheses, see below for
1787 .Bl -tag -compact -width ".It Ar _n_u"
1788 .It Ar ( criterion )
1789 All messages that satisfy the given
1791 .It Ar ( criterion1 criterion2 ... criterionN )
1792 All messages that satisfy all of the given criteria.
1794 .It Ar ( or criterion1 criterion2 )
1795 All messages that satisfy either
1800 To connect more than two criteria using
1802 specifications have to be nested using additional parentheses,
1804 .Ql (or a (or b c)) ,
1808 .Ql ((a or b) and c) .
1811 operation of independent criteria on the lowest nesting level,
1812 it is possible to achieve similar effects by using three separate
1816 .It Ar ( not criterion )
1817 All messages that do not satisfy
1819 .It Ar ( bcc \*q Ns Ar string Ns Ar \*q )
1820 All messages that contain
1822 in the envelope representation of the
1825 .It Ar ( cc \*q Ns Ar string Ns Ar \*q )
1826 All messages that contain
1828 in the envelope representation of the
1831 .It Ar ( from \*q Ns Ar string Ns Ar \*q )
1832 All messages that contain
1834 in the envelope representation of the
1837 .It Ar ( subject \*q Ns Ar string Ns Ar \*q )
1838 All messages that contain
1843 .It Ar ( to \*q Ns Ar string Ns Ar \*q )
1844 All messages that contain
1846 in the envelope representation of the
1849 .It Ar ( header name \*q Ns Ar string Ns Ar \*q )
1850 All messages that contain
1855 .It Ar ( body \*q Ns Ar string Ns Ar \*q )
1856 All messages that contain
1859 .It Ar ( text \*q Ns Ar string Ns Ar \*q )
1860 All messages that contain
1862 in their header or body.
1863 .It Ar ( larger size )
1864 All messages that are larger than
1867 .It Ar ( smaller size )
1868 All messages that are smaller than
1872 .It Ar ( before date )
1873 All messages that were received before
1875 which must be in the form
1879 denotes the day of the month as one or two digits,
1881 is the name of the month \(en one of
1882 .Ql Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ,
1885 is the year as four digits, e.g.,
1889 All messages that were received on the specified date.
1890 .It Ar ( since date )
1891 All messages that were received since the specified date.
1892 .It Ar ( sentbefore date )
1893 All messages that were sent on the specified date.
1894 .It Ar ( senton date )
1895 All messages that were sent on the specified date.
1896 .It Ar ( sentsince date )
1897 All messages that were sent since the specified date.
1899 The same criterion as for the previous search.
1900 This specification cannot be used as part of another criterion.
1901 If the previous command line contained more than one independent
1902 criterion then the last of those criteria is used.
1906 .\" .Ss "On URL syntax and credential lookup" {{{
1907 .Ss "On URL syntax and credential lookup"
1909 \*(IN For accessing protocol-specific resources usage of Uniform
1910 Resource Locators (URL, RFC 1738) has become omnipresent.
1911 \*(UA expects and understands URLs in the following form;
1914 denote optional parts, optional either because there also exist other
1915 ways to define the information in question or because support of the
1916 part is protocol-specific (e.g.,
1918 is used by the IMAP protocol but not by POP3);
1923 are specified they must be given in URL percent encoded form (RFC 3986;
1931 .Dl PROTOCOL://[USER[:PASSWORD]@]server[:port][/path]
1934 Note that these \*(UA URLs most often don't conform to any real
1935 standard, but instead represent a normalized variant of RFC 1738 \(en
1936 they are not used in data exchange but only ment as a compact,
1937 easy-to-use way of defining and representing information in
1938 a well-known notation.
1941 Many internal variables of \*(UA exist in multiple versions, called
1942 variable chains for the rest of this document: the plain
1947 .Ql variable-USER@HOST .
1954 had been specified in the respective URL, otherwise it refers to the plain
1960 that had been found when doing the user chain lookup as is described
1963 will never be in URL percent encoded form, wether it came from an URL or
1964 not; i.e., values of
1965 .Sx "INTERNAL VARIABLES"
1966 must not be URL percent encoded.
1969 For example, wether an hypothetical URL
1970 .Ql smtp://hey%3Ayou@our.house
1971 had been given that includes a user, or wether the URL was
1972 .Ql smtp://our.house
1973 and the user had been found differently, to lookup the variable chain
1974 .Va smtp-use-starttls
1975 \*(UA first looks for wether
1976 .Ql smtp-\:use-\:starttls-\:hey:you@our.house
1977 is defined, then wether
1978 .Ql smtp-\:use-\:starttls-\:our.house
1979 exists before finally ending up looking at the plain variable itself.
1982 \*(UA obeys the following logic scheme when dealing with the
1983 necessary credential informations of an account:
1989 has been given in the URL the variables
1993 are looked up; if no such variable(s) can be found then \*(UA will,
1994 when enforced by the \*(OPal variables
1995 .Va netrc-lookup-HOST
2002 specific entry which provides a
2004 name: this lookup will only succeed if unambiguous (one possible matching
2008 If there is still no
2010 then \*(UA will fall back to the user who is supposed to run \*(UA:
2011 either the name that has been given with the
2013 command line option (or, equivalently, but with less precedence, the
2014 environment variable
2019 The identity of this user has been fixated during \*(UA startup and is
2020 known to be a valid user on the current host.
2023 Authentication: unless otherwise noted this will lookup the
2024 .Va PROTOCOL-auth-USER@HOST , PROTOCOL-auth-HOST , PROTOCOL-auth
2025 variable chain, falling back to a protocol-specific default should this
2031 has been given in the URL, then if the
2033 has been found through the \*(OPal
2035 then that may have already provided the password, too.
2036 Otherwise the variable chain
2037 .Va password-USER@HOST , password-HOST , password
2038 is looked up and used if existent.
2040 \*(OP Then if any of the variables of the chain
2041 .Va agent-shell-lookup-USER@HOST , agent-shell-lookup-HOST , \
2043 is set the shell command specified therein is run and the output (less
2044 newline characters) will be used as the password.
2045 It is perfectly valid for such an agent to simply not return any data,
2046 in which case the password lookup is continued somewhere else;
2047 Any command failure is treated as a hard error, however.
2049 Afterwards the complete \*(OPal variable chain
2050 .Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup
2054 cache is searched for a password only (multiple user accounts for
2055 a single machine may exist as well as a fallback entry without user
2056 but with a password).
2058 If at that point there is still no password available, but the
2059 (protocols') chosen authentication type requires a password, then in
2060 interactive mode the user will be prompted on the terminal.
2065 S/MIME verification works relative to the values found in the
2069 header field(s), which means that the values of
2070 .Va smime-sign , smime-sign-cert , smime-sign-include-certs
2072 .Va smime-sign-message-digest
2073 will not be looked up using the
2077 chains from above but instead use the corresponding values from the
2078 message that is being worked on.
2079 In unusual cases multiple and different
2083 combinations may therefore be involved \(en on the other hand those
2084 unusual cases become possible.
2085 The usual case is as short as:
2088 .Dl set smtp=smtp://USER:PASS@HOST smtp-use-starttls \e
2089 .Dl \ \ \ \ smime-sign smime-sign-cert=+smime.pair
2094 contains complete example configurations.
2097 .\" .Ss "Command line editor" {{{
2098 .Ss "Command line editor"
2100 \*(OP \*(UA can be configured to support a command line editor and
2101 command history lists which are saved in between sessions.
2102 One may link against fully-fledged external libraries
2103 .Pf ( Xr readline 6 ,
2105 ) or use \*(UA's own command line editor NCL (Nail-Command-Line)
2106 instead, which should work in all environments which comply to the
2107 ISO C standard (ISO/IEC 9899:1990/Amendment 1:1995).
2108 When an external library is used, interactive behaviour of \*(UA relies
2109 on that library and may not correspond one-to-one to what is described
2113 Regardless of the actually used command line editor
2115 entries will be created for lines entered in command mode only, and
2116 creation of such an entry can be forcefully suppressed by starting the
2117 line with a space character.
2120 handling is by itself an optional feature and may therefore not be
2122 For more information see the documentation of the variables
2126 .Va history-gabby-persist ,
2129 .Va line-editor-disable .
2130 And there is also the \*(OPal
2132 will can be set to cause overall screen resets when \*(UA releases the
2133 terminal in interactive mode.
2136 The builtin \*(UA command line editor supports the following operations;
2139 stands for the combination of the
2141 key plus the mentioned character, e.g.,
2144 .Dq hold down control key and press the A key :
2147 .Bl -tag -compact -width "Ql _M"
2149 Go to the start of the line.
2151 Move the cursor backward one character.
2153 Forward delete the character under the cursor;
2154 quits \*(UA if used on the empty line unless the
2158 Go to the end of the line.
2160 Move the cursor forward one character.
2163 Cancel current operation, full reset.
2164 If there is an active history search or tabulator expansion then this
2165 command will first reset that, reverting to the former line content;
2166 thus a second reset is needed for a full reset in this case.
2167 In all cases \*(UA will reset a possibly used multibyte character input
2173 backward delete one character.
2177 .Dq horizontal tabulator :
2178 try to expand the word before the cursor.
2180 .Dq tabulator-completion
2181 as is known from the
2183 but really means the usual \*(UA expansion, as documented for
2185 yet it involves shell expansion as a last step, too.)
2190 complete this line of input.
2192 Delete all characters from the cursor to the end of the line.
2196 \*(OP Go to the next history entry.
2201 \*(OP Go to the previous history entry.
2203 \*(OP Complete the current line from (the remaining older) history entries.
2210 Delete the characters from the one preceding the cursor to the preceding
2213 Move the cursor forward one word boundary.
2215 Move the cursor backward one word boundary.
2219 If problems with commands that are based upon rightwise movement are
2220 encountered, adjustments of the option
2221 .Va line-editor-cursor-right
2222 may solve the problem, as documented for it.
2225 If the terminal produces key sequences which are compatible with
2227 then the left and right cursor keys will map to
2231 respectively, the up and down cursor keys will map to
2235 and the Home/End/PgUp/PgDown keys will call the
2237 command with the respective arguments
2243 (i.e., perform scrolling through the header summary list).
2244 Also the up and down cursor keys should invoke
2246 for up- and downwards movement if they are used while the
2251 .\" .Ss "Coloured display" {{{
2252 .Ss "Coloured display"
2254 \*(OP \*(UA can be configured to support a coloured display and font
2256 Colour usage depends on the value of the environment variable
2258 if that is not set or set to the value
2260 then this section doesn't apply, if the value includes the string
2262 or if it can be found (case-insensitively) in the variable
2264 then \*(UA will assume a colour-enabled display, but otherwise
2265 a monochrome display is assumed.
2268 On top of what \*(UA knows about the terminal the boolean variable
2270 defines wether colour and font attribute sequences should also be
2271 generated when the output of a command needs to go through the
2276 This is not enabled by default because different pager programs need
2277 different command line switches or other configuration in order to
2278 support those colour sequences.
2279 \*(UA knows about some widely used pagers and in a clean environment
2280 it is often enough to simply set
2282 please refer to that variable for more on this topic.
2287 is set then any active usage of colour and font attribute sequences
2288 is suppressed, but without affecting possibly established
2293 To define and control colours and font attributes a single multiplexer
2294 command family exists:
2296 shows or defines colour mappings for the given colour type (e.g.,
2299 can be used to remove mappings of a given colour type.
2300 Since colours are only available in interactive mode, it may make
2301 sense to conditionalize the colour setup by encapsulating it with
2304 .Bd -literal -offset indent
2306 colour iso view-msginfo ft=bold,fg=green
2307 colour iso view-header ft=bold,fg=red "from,subject"
2308 colour iso view-header fg=red
2310 uncolour iso view-header from,subject
2311 colour iso view-header ft=bold,fg=magenta,bg=cyan
2312 colour 256 view-header ft=bold,fg=208,bg=230 subject,from
2313 colour mono view-header ft=bold
2314 colour mono view-header ft=bold,ft=reverse subject,from
2318 .\" }}} (DESCRIPTION)
2321 .\" .Sh COMMANDS {{{
2324 Each command is typed on a line by itself,
2325 and may take arguments following the command word.
2326 The command need not be typed in its entirety \(en
2327 the first command which matches the typed prefix is used.
2328 An \(en alphabetically \(en sorted list of commands can be shown
2335 when given an argument, will show a documentation string for the
2336 command matching the expanded argument, as in
2338 which should be a shorthand of
2340 documentation strings are however \*(OPal.
2343 For commands which take message lists as arguments, the next message
2344 forward that satisfies the command's requirements will be used shall no
2345 explicit message list have been specified.
2346 If there are no messages forward of the current message,
2347 the search proceeds backwards,
2348 and if there are no good messages at all,
2350 .Dq no applicable messages
2351 and aborts the command.
2352 The arguments to commands can be quoted, using the following methods:
2355 .Bl -bullet -compact -offset indent
2357 An argument can be enclosed between paired double-quotes
2362 any white space, shell word expansion, or backslash characters (except
2363 as described next) within the quotes are treated literally as part of
2365 A double-quote will be treated literally within single-quotes and vice
2367 Inside such a quoted string the actually used quote character can be
2368 used nonetheless by escaping it with a backslash
2374 An argument that is not enclosed in quotes, as above, can usually still
2375 contain space characters if those spaces are backslash-escaped, as in
2379 A backslash outside of the enclosing quotes is discarded
2380 and the following character is treated literally as part of the argument.
2383 An unquoted backslash at the end of a command line is discarded and the
2384 next line continues the command.
2388 Filenames, where expected, are subsequently subjected to the following
2389 transformations, in sequence:
2392 .Bl -bullet -compact -offset indent
2394 If the filename begins with an unquoted plus sign, and the
2396 variable is defined,
2397 the plus sign will be replaced by the value of the
2399 variable followed by a slash.
2402 variable is unset or is set to null, the filename will be unchanged.
2405 Shell word expansions are applied to the filename.
2406 .\" TODO shell word expansion shell expand fexpand FEXP_NSHELL
2407 .Sy Compatibility note:
2408 on the long run support for complete shell word expansion will be
2409 replaced by an internally implemented restricted expansion mechanism in
2410 order to circumvent possible security impacts through shell expansion.
2411 Expect that a growing number of program parts only support this
2414 Meta expansions are applied to the filename: leading tilde characters
2416 will be replaced by the expansion of
2418 and any occurrence of
2422 will be replaced by the expansion of the variable, if possible;
2423 \*(UA internal as well as environmental (shell) variables can be
2424 accessed through this mechanism.
2425 In order to include a raw
2427 character precede it with a backslash
2429 to include a backslash double it.
2430 If more than a single pathname results from this expansion and the
2431 command is expecting one file, an error results.
2433 Note that in interactive display context, in order to allow simple
2434 value acceptance (typing
2436 backslash quoting is performed automatically as necessary, e.g., a file
2437 .Ql diet\e is \ecurd.txt
2438 will be displayed as
2439 .Ql diet\e\e is \e\ecurd.txt .
2443 The following commands are available:
2445 .Bl -tag -width ".Ic _ccount"
2452 ) command which follows.
2456 The comment-command causes the entire line to be ignored.
2458 this really is a normal command which' purpose is to discard its
2461 indicating special character, which means that, e.g., trailing comments
2462 on a line are not possible.
2466 Goes to the next message in sequence and types it
2472 Display the preceding message, or the n'th previous message if given
2473 a numeric argument n.
2477 Show the current message number (the
2482 Show a brief summary of commands.
2483 \*(OP Given an argument a synopsis for the command in question is
2484 shown instead; commands can be abbreviated in general and this command
2485 can be used to see the full expansion of an abbreviation including the
2486 synopsis, try, e.g.,
2491 and see how the output changes.
2501 Interprets the remainder of the word as a macro name and passes it
2506 is a shorter synonym for
2507 .Ql call Ar mymacro .
2511 (ac) Creates, selects or lists (an) account(s).
2512 An account is a group of commands and variable settings which together
2513 usually arrange the environment for the purpose of creating a system login.
2514 Without any argument a listing of all defined accounts and their content
2516 A specific account can be activated by giving solely its name, resulting
2517 in the system mailbox or inbox of that account to be activated as via an
2518 explicit use of the command
2520 The two argument form is identical to defining a macro as via
2523 .Bd -literal -offset indent
2527 set from="myname@myisp.example (My Name)"
2528 set smtp=smtp://mylogin@smtp.myisp.example
2532 creates an account named
2534 which can later be selected by specifying
2538 (case-insensitive) always exists.
2540 are enabled by default and localize account settings \(en different to
2541 normal macros the settings will be reverted once the account is switched off.
2542 Accounts can be deleted via
2547 (a) With no arguments, shows all currently-defined aliases.
2548 With one argument, shows that alias.
2549 With more than one argument,
2550 creates a new alias or appends to an existing one.
2552 can be used to delete aliases.
2556 (alt) Manage a list of alternate addresses / names of the active user,
2557 members of which will be removed from recipient lists when replying to
2560 variable is not set).
2561 If arguments are given the set of alternate names is replaced by them,
2562 without arguments the current set is displayed.
2566 Takes a message list and marks each message as having been answered.
2567 This mark has no technical meaning in the mail system;
2568 it just causes messages to be marked in the header summary,
2569 and makes them specially addressable.
2573 Calls a macro that has been created via
2578 (ch) Change the working directory to
2580 or the given argument.
2586 \*(OP Only applicable to S/MIME signed messages.
2587 Takes a message list and a file name and saves the certificates
2588 contained within the message signatures to the named file in both
2589 human-readable and PEM format.
2590 The certificates can later be used to send encrypted messages to the
2591 respective message senders by setting
2592 .Va smime-encrypt-USER@HOST
2597 (ch) Change the working directory to
2599 or the given argument.
2605 Only applicable to threaded mode.
2606 Takes a message list and makes all replies to these messages invisible
2607 in header summaries, unless they are in state
2613 \*(OP Manage colour mappings for the type of colour given as the
2614 (case-insensitive) first argument, which must be one of
2616 for 256-colour terminals,
2621 for the standard 8-colour ANSI / ISO 6429 color palette and
2625 for monochrome terminals.
2626 Monochrome terminals cannot deal with colours, but only (some) font
2630 Without further arguments the list of all currently defined mappings for
2631 the given colour type is shown.
2632 Otherwise the second argument defines the mappable slot, the third
2633 argument a (comma-separated list of) colour and font attribute
2634 specification(s), and the optional fourth argument can be used to
2635 specify a precondition: if conditioned mappings exist they are tested in
2636 (creation) order unless a (case-insensitive) match has been found, and
2637 the default mapping (if any has been established) will only be chosen as
2639 The types of precondition available depend on the mappable slot, the
2640 following of which exist:
2643 .Bl -tag -compact -width view-partinfo
2645 Mappings prefixed with
2647 are used in header summaries, and they all understand the preconditions
2649 (the current message) and
2651 for elder messages (only honoured in conjunction with
2652 .Va datefield-markout-older ) .
2653 This mapping is used for the
2655 that can be created with the
2659 formats of the variable
2662 For the complete header summary line except the
2664 and the thread structure.
2666 For the thread structure which can be created with the
2668 format of the variable
2672 Mappings prefixed with
2674 are used when displaying messages.
2675 This mapping is used for so-called
2677 lines, which are MBOX file format specific header lines.
2680 A comma-separated list of headers to which the mapping applies may be
2681 given as a precondition; if the \*(OPal regular expression support is
2682 available then if any of the
2684 (extended) regular expression characters is seen the precondition will
2685 be evaluated as (an extended) one.
2687 For the introductional message info line.
2688 .It Cd view-partinfo
2689 For MIME part info lines.
2693 The following (case-insensitive) colour definitions and font attributes
2694 are understood, multiple of which can be specified in a comma-separated
2704 It is possible (and often applicable) to specify multiple font
2705 attributes for a single mapping.
2708 foreground colour attribute:
2718 To specify a 256-color mode a decimal number colour specification in
2719 the range 0 to 255, inclusive, is supported, and interpreted as follows:
2721 .Bl -tag -compact -width "999 - 999"
2723 the standard ISO 6429 colors, as above.
2725 high intensity variants of the standard colors.
2727 216 colors in tuples of 6.
2729 grayscale from black to white in 24 steps.
2731 .Bd -literal -offset indent
2733 fg() { printf "\e033[38;5;${1}m($1)"; }
2734 bg() { printf "\e033[48;5;${1}m($1)"; }
2736 while [ $i -lt 256 ]; do fg $i; i=$(($i + 1)); done
2737 printf "\e033[0m\en"
2739 while [ $i -lt 256 ]; do bg $i; i=$(($i + 1)); done
2740 printf "\e033[0m\en"
2744 background colour attribute (see
2746 for possible values).
2750 Mappings may be removed with the command
2752 For a generic overview see the section
2753 .Sx "Coloured display" .
2758 (C) Copy messages to files whose names are derived from the author of
2759 the respective message and don't mark them as being saved;
2760 otherwise identical to
2765 (c) Copy messages to the named file and don't mark them as being saved;
2766 otherwise identical to
2771 With no arguments, shows all currently-defined custom headers.
2772 With one argument, shows that custom header.
2773 With more than one argument, creates a new or replaces an existing
2774 custom header with the name given as the first argument, the content of
2775 which being defined by the concatenated remaining arguments.
2777 can be used to delete custom headers.
2778 \*(ID Overwriting of automatically managed headers is neither supported
2780 Defined custom headers will be injected into newly composed or forwarded
2783 .Dl customhdr OpenPGP id=12345678; url=http://www.YYY.ZZ
2787 may also be used to inject custom headers; it is covered by
2792 Show the name of the current working directory.
2796 \*(OP For unencrypted messages this command is identical to
2798 Encrypted messages are first decrypted, if possible, and then copied.
2802 \*(OP For unencrypted messages this command is identical to
2804 Encrypted messages are first decrypted, if possible, and then copied.
2808 Without arguments the current list of macros, including their content,
2809 is shown, otherwise a macro is defined.
2810 A macro definition is a sequence of commands in the following form:
2811 .Bd -literal -offset indent
2820 A defined macro can be invoked explicitly by using the
2824 commands, or implicitly if a macro hook is triggered, e.g., a
2826 Note that interpretation of
2828 depends on how (i.e.,
2830 normal macro, folder hook, hook, account switch) the macro is invoked.
2831 Macros can be deleted via
2835 Macro behaviour, including option localization, will change in v15.
2836 Please be aware of that and possibly embed a version check in a resource
2841 (d) Marks the given message list as
2843 Deleted messages will neither be saved in
2845 nor will they be available for most other commands.
2857 Deletes the current message and displays the next message.
2858 If there is no next message, \*(UA says
2865 up or down by one message when given
2869 argument, respectively.
2873 Takes a message list and marks each given message as a draft.
2874 This mark has no technical meaning in the mail system;
2875 it just causes messages to be marked in the header summary,
2876 and makes them specially addressable.
2880 (ec) Echoes its arguments,
2881 resolving special names as documented for the command
2883 The escape sequences
2895 are interpreted just as they are by
2897 (proper quoting provided).
2901 (e) Point the text editor (as defined in
2903 at each message from the given list in turn.
2904 Modified contents are discarded unless the
2911 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
2912 conditional \(em if the condition of a preceeding
2914 was false, check the following condition and execute the following block
2915 if it evaluates true.
2920 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
2921 conditional \(em if none of the conditions of the preceeding
2925 commands was true, the
2931 (en) Marks the end of an
2932 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
2933 conditional execution block.
2937 \*(OP Since \*(UA uses the console as a user interface it can happen
2938 that messages scroll by too fast to become recognized.
2939 Optionally an error message ring queue is available which stores
2940 duplicates of any error message and notifies the user in interactive
2941 sessions whenever a new error has occurred.
2942 The queue is finite: if its maximum size is reached any new message
2943 replaces the eldest.
2946 can be used to manage this message queue: if given
2948 or no argument the queue will be displayed and cleared,
2950 will only clear all messages from the queue.
2954 (ex or x) Exit from \*(UA without changing the active mailbox and skip
2955 any saving of messages in
2957 as well as a possibly tracked command line editor history file.
2961 Show the list of features that have been compiled into \*(UA.
2962 (Outputs the contents of the variable
2969 but open the mailbox readonly.
2973 (fi) The file command switches to a new mailbox.
2974 Without arguments it shows status information of the current mailbox.
2975 If an argument is given, it will write out changes (such as deletions)
2976 the user has made and open a new mailbox.
2977 Some special conventions are recognized for the
2981 .Bl -tag -compact -offset indent -width ".Ar %:__lespec"
2983 (number sign) means the previous file,
2985 (percent sign) means the invoking user's system mailbox,
2987 means the system mailbox of
2989 (and never the value of
2991 regardless of its actual setting),
2993 (ampersand) means the invoking user's
3003 expands to the same value as
3005 but the file is handled as a system mailbox by, e.g., the
3009 commands, meaning that messages that have been read in the current
3010 session will be moved to the
3012 mailbox instead of simply being flagged as read.
3015 If the name matches one of the strings defined with the command
3017 it is replaced by its long form and expanded.
3018 If the name ends with
3023 it is treated as being compressed with
3028 respectively, and transparently handled through an intermediate
3029 (un)compression step (using a temporary file) with the according
3030 facility, sufficient support provided.
3031 Likewise, if the named file doesn't exist, but a file with one of the
3032 mentioned compression extensions does, then the name is automatically
3033 expanded and the compressed file is used.
3035 Otherwise, if the name ends with an extension for which
3036 .Va file-hook-load-EXTENSION
3038 .Va file-hook-save-EXTENSION
3039 variables are set, then the given hooks will be used to load and save
3041 and \*(UA will work with an intermediate temporary file.
3043 MBOX files (flat file-based mailboxes) are generally locked during file
3044 operations in order to avoid inconsistencies due to concurrent
3046 \*(OPal Mailbox files which \*(UA treats as system or primary mailboxes
3047 will also be protected by so-called dotlock files, the traditional way
3048 of mail spool file locking: for any file
3052 will be created for the duration of the synchronization \(em
3053 as necessary a privilege-separated dotlock child process will be used
3054 to accommodate for necessary privilege adjustments in order to create
3055 the dotlock file in the same directory
3056 and with the same user and group identities as the file of interest.
3059 for fine-tuning the handling of MBOX files.
3063 refers to a directory with the subdirectories
3068 then it is treated as a folder in
3073 .Dl \*(IN protocol://[user[:password]@]host[:port][/path]
3074 .Dl \*(OU protocol://[user@]host[:port][/path]
3076 is taken as an Internet mailbox specification.
3077 The \*(OPally supported protocols are
3081 (POP3 with SSL/TLS encrypted transport).
3084 part is valid only for IMAP; there it defaults to
3086 Also see the section
3087 .Sx "On URL syntax and credential lookup" .
3091 contains special characters, in particular
3095 they must be escaped in URL notation \(en the command
3097 can be used to show the necessary conversion.
3101 Takes a message list and marks the messages as
3103 ged for urgent/special attention.
3104 This mark has no technical meaning in the mail system;
3105 it just causes messages to be highlighted in the header summary,
3106 and makes them specially addressable.
3115 With no arguments, list the names of the folders in the folder directory.
3116 With an existing folder as an argument,
3117 lists the names of folders below the named folder.
3123 but saves the message in a file named after the local part of the first
3124 recipient's address (instead of in
3131 but saves the message in a file named after the local part of the first
3132 recipient's address (instead of in
3139 but responds to all recipients regardless of the
3144 .It Ic followupsender
3147 but responds to the sender only regardless of the
3163 (f) Takes a list of message specifications and displays a summary of
3164 their message headers, as via
3166 An alias of this command is
3169 .Sx "Specifying messages" .
3175 but saves the message in a file named after the local part of the
3176 recipient's address (instead of in
3181 Takes a message and the address of a recipient
3182 and forwards the message to him.
3183 The text of the original message is included in the new one,
3184 with the value of the
3186 variable preceding it.
3191 commands specify which header fields are included in the new message.
3192 Only the first part of a multipart message is included unless the
3193 .Va forward-as-attachment
3197 is set recipient addresses will be stripped from comments, names etc.
3201 Specifies which header fields are to be ignored with the command
3203 This command has no effect when the
3204 .Va forward-as-attachment
3209 Specifies which header fields are to be retained with the command
3214 This command has no effect when the
3215 .Va forward-as-attachment
3220 Define or list command aliases, so-called ghosts.
3221 Without arguments a list of all currently known aliases is shown.
3222 With one argument the expansion of the given alias is shown.
3223 With two or more arguments a command alias is defined or updated: the
3224 first argument is the name under which the remaining command line should
3225 be accessible, the content of which can be just about anything.
3226 A ghost can be used everywhere a normal command can be used, but always
3227 takes precedence; any arguments that are given to the command alias are
3228 joined onto the alias content, and the resulting string forms the
3229 command line that is, in effect, executed.
3232 .Bd -literal -offset indent
3234 `ghost': no such alias: "xx"
3237 ghost xx "echo hello,"
3246 (h) Show the current group of headers, the size of which depends on
3249 and the style of which can be adjusted with the variable
3251 If a message-specification is given the group of headers containing the
3252 first message therein is shown and the message at the top of the screen
3267 the list of history entries;
3270 argument selects and shows the respective history entry \(en
3273 to accept it, and the history entry will become the new history top.
3274 The default mode if no arguments are given is
3281 Takes a message list and marks each message therein to be saved in the
3282 user's system mailbox instead of in
3284 Does not override the
3287 \*(UA deviates from the POSIX standard with this command, because a
3289 command issued after
3291 will display the following message, not the current one.
3296 (i) Part of the nestable
3297 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3298 conditional execution construct \(em if the given condition is true then
3299 the encapsulated block is executed.
3300 POSIX only supports the (case-insensitive) conditions
3305 end, all remaining conditions are non-portable extensions; note that
3306 falsely specified conditions cause the execution of the entire
3307 conditional construct until the (matching) closing
3309 command to be suppressed.
3310 The syntax of the nestable
3312 conditional execution construct requires that each condition and syntax
3313 element is surrounded by whitespace.
3315 .Bd -literal -offset indent
3324 The (case-insensitive) condition
3326 erminal will evaluate to true if the standard input is a terminal, i.e.,
3327 in interactive sessions.
3328 Another condition can be any boolean value (see the section
3329 .Sx "INTERNAL VARIABLES"
3330 for textual boolean representations) to mark an enwrapped block as
3333 .Dq always execute .
3334 It is possible to check
3335 .Sx "INTERNAL VARIABLES"
3338 variables for existence or compare their expansion against a user given
3339 value or another variable by using the
3341 .Pf ( Dq variable next )
3342 conditional trigger character;
3343 a variable on the right hand side may be signalled using the same
3345 The variable names may be enclosed in a pair of matching braces.
3348 The available comparison operators are
3352 (less than or equal to),
3358 (greater than or equal to),
3362 (is substring of) and
3364 (is not substring of).
3365 The values of the left and right hand side are treated as strings and
3366 are compared 8-bit byte-wise, ignoring case according to the rules of
3367 the US-ASCII encoding (therefore, dependend on the active locale,
3368 possibly producing false results for strings in the locale encoding).
3369 Except for the substring checks the comparison will instead be performed
3370 arithmetically if both, the user given value as well as the variable
3371 content, can be parsed as numbers (integers).
3372 An unset variable is treated as the empty string.
3375 When the \*(OPal regular expression support is available, the additional
3381 They treat the right hand side as an extended regular expression that is
3382 matched case-insensitively and according to the active
3384 locale, meaning that strings in the locale encoding should be matched
3388 Conditions can be joined via AND-OR lists (where the AND operator is
3390 and the OR operator is
3392 which have equal precedence and will be evaluated with left
3393 associativity, thus using the same syntax that is known for the
3395 It is also possible to form groups of conditions and lists by enclosing
3396 them in pairs of brackets
3397 .Ql [\ \&.\&.\&.\ ] ,
3398 which may be interlocked within each other, and also be joined via
3402 The results of individual conditions and entire groups may be modified
3403 via unary operators: the unary operator
3405 will reverse the result.
3407 .Bd -literal -offset indent
3411 if $ttycharset == "UTF-8"
3412 echo *ttycharset* is set to UTF-8, case-insensitively
3416 echo These two variables are equal
3418 if $version-major >= 15
3419 echo Running a new version..
3420 if $features =@ "regex"
3421 if $TERM =~ "^xterm\&.*"
3422 echo ..in an X terminal
3425 if [ [ true ] && [ [ ${debug} ] || [ $verbose ] ] ]
3428 if true && $debug || ${verbose}
3429 echo Left associativity, as is known from the shell
3431 if ! ! true && ! [ ! $debug && ! $verbose ]
3432 echo Unary operator support
3440 Without arguments the list of ignored header fields is shown,
3441 otherwise the given list of header fields is added to the ignore list:
3442 Header fields in the ignore list are not shown on the terminal when
3443 a message is displayed.
3444 To display a message in its entirety, use the commands
3455 Shows the names of all available commands, alphabetically sorted.
3459 This command can be used to localize changes to variables, meaning that
3460 their state will be reverted to the former one once the covered scope
3462 It can only be used inside of macro definition blocks introduced by
3466 and is interpreted as a boolean (string, see
3467 .Sx "INTERNAL VARIABLES" ) ;
3470 of an account is left once it is switched off again.
3471 .Bd -literal -offset indent
3472 define temporary_settings {
3487 enables change localization and calls
3489 which explicitly resets localization, then any value changes within
3491 will still be reverted by
3496 Reply to messages that come in via known
3499 .Pf ( Ic mlsubscribe )
3500 mailing lists, or pretend to do so (see
3501 .Sx "Mailing lists" ) :
3504 functionality this will actively resort and even remove message
3505 recipients in order to generate a message that is supposed to be sent to
3507 For example it will also implicitly generate a
3508 .Ql Mail-Followup-To:
3509 header if that seems useful, regardless of the setting of the variable
3516 but saves the message in a file named after the local part of the first
3517 recipient's address (instead of in
3522 (m) Takes a (list of) recipient address(es) as (an) argument(s),
3523 or asks on standard input if none were given;
3524 then collects the remaining mail content and sends it out.
3528 (mb) The given message list is to be sent to
3530 when \*(UA is quit; this is the default action unless the
3533 \*(ID This command can only be used in a system mailbox (see
3538 Without any arguments the content of the MIME type cache will displayed.
3539 Otherwise each argument defines a complete MIME type specification of
3540 a type that shall be added (prepended) to the cache.
3541 In any event MIME type sources are loaded first as necessary \(en
3542 .Va mimetypes-load-control
3543 can be used to fine-tune which sources are actually loaded.
3544 Refer to the section on
3545 .Sx "The mime.types files"
3546 for more on MIME type specifications and this topic in general.
3547 MIME type unregistration and cache resets can be triggered with
3552 Without arguments the list of all currently defined mailing lists
3553 (and their attributes, if any) is shown.
3554 Otherwise all given arguments (which need not be quoted except for
3555 whitespace) will be added and henceforth be recognized as mailing lists.
3556 Mailing lists may be removed via the command
3559 If the \*(OPal regular expression support is available then mailing
3560 lists may also be specified as (extended) regular expressions (see
3566 Without arguments the list of all currently defined mailing lists which
3567 have a subscription attribute is shown.
3568 Otherwise this attribute will be set for all given mailing lists,
3569 newly creating them as necessary (as via
3571 Subscription attributes may be removed via the command
3580 but moves the messages to a file named after the local part of the
3581 sender address of the first message (instead of in
3588 but marks the messages for deletion if they were transferred
3595 but also displays ignored header fields and all MIME parts.
3603 on the given messages, even in non-interactive mode and as long as the
3604 standard output is a terminal.
3610 \*(OP When used without arguments or if
3612 has been given the content of the
3614 cache is shown, loading it first as necessary,
3617 then the cache will only be initialized and
3619 will remove its contents.
3620 Note that \*(UA will try to load the file only once, use
3621 .Ql Ic netrc Ns \:\0\:clear
3622 to unlock further attempts.
3626 .Sx "On URL syntax and credential lookup" ;
3628 .Sx "The .netrc file"
3629 documents the file format in detail.
3633 Checks for new mail in the current folder without committing any changes
3635 If new mail is present, a message is shown.
3639 the headers of each new message are also shown.
3647 Goes to the next message in sequence and types it.
3648 With an argument list, types the next matching message.
3662 If the current folder is accessed via a network connection, a
3664 command is sent, otherwise no operation is performed.
3670 but also displays ignored header fields and all MIME parts.
3678 on the given messages, even in non-interactive mode and as long as the
3679 standard output is a terminal.
3687 but also pipes ignored header fields and all parts of MIME
3688 .Ql multipart/alternative
3693 (pi) Takes a message list and a shell command
3694 and pipes the messages through the command.
3695 Without an argument the current message is piped through the command
3702 every message is followed by a formfeed character.
3723 (q) Terminates the session, saving all undeleted, unsaved messages in
3726 preserving all messages marked with
3730 or never referenced in the system mailbox,
3731 and removing all other messages from the system mailbox.
3732 If new mail has arrived during the session,
3734 .Dq You have new mail
3736 If given while editing a mailbox file with the command line flag
3738 then the edit file is rewritten.
3739 A return to the shell is effected,
3740 unless the rewrite of edit file fails,
3741 in which case the user can escape with the exit command.
3755 Removes the named folders.
3756 The user is asked for confirmation in interactive mode.
3760 Takes the name of an existing folder
3761 and the name for the new folder
3762 and renames the first to the second one.
3763 Both folders must be of the same type.
3767 (R) Reply to originator.
3768 Does not reply to other recipients of the original message.
3770 will exchange this command with
3774 is set the recipient address will be stripped from comments, names etc.
3778 (r) Take a message and group-responds to it by addressing the sender
3781 .Va followup-to-honour ,
3784 .Va recipients-in-cc
3785 influence response behaviour.
3788 offers special support for replying to mailing lists.
3791 is set recipient addresses will be stripped from comments, names etc.
3804 but initiates a group-reply regardless of the value of
3811 but responds to the sender only regardless of the value of
3818 but does not add any header lines.
3819 This is not a way to hide the sender's identity,
3820 but useful for sending a message again to the same recipients.
3824 Takes a list of messages and a user name
3825 and sends each message to the named user.
3827 and related header fields are prepended to the new copy of the message.
3845 .It Ic respondsender
3851 (ret) Without arguments the list of retained header fields is shown,
3852 otherwise the given list of header fields is added to the retain list:
3853 Header fields in the retain list are shown on the terminal when
3854 a message is displayed, all other header fields are suppressed.
3855 To display a message in its entirety, use the commands
3864 takes precedence over the mentioned.
3870 but saves the messages in a file named after the local part of the
3871 sender of the first message instead of (in
3873 and) taking a filename argument.
3877 (s) Takes a message list and a filename and appends each message in turn
3878 to the end of the file.
3879 If no filename is given, the
3882 The filename in quotes, followed by the generated character count
3883 is echoed on the user's terminal.
3884 If editing a system mailbox the messages are marked for deletion.
3885 Filename interpretation as described for the
3887 command is performed.
3904 Header fields thus marked are filtered out when saving a message by
3906 or when automatically saving to
3908 This command should only be applied to header fields that do not contain
3909 information needed to decode the message,
3910 as MIME content fields do.
3922 Header fields thus marked are the only ones saved with a message when
3925 or when automatically saving to
3930 The use of this command is strongly discouraged since it may strip
3931 header fields that are needed to decode the message correctly.
3935 Takes a message specification (list) and displays a header summary of
3936 all matching messages, as via
3938 This command is an alias of
3941 .Sx "Specifying messages" .
3945 Takes a message list and marks all messages as having been read.
3949 (se) Without arguments this command shows all variables and their
3950 values which are currently known to \*(UA.
3951 Setting any of the variables
3955 changes the output format to BSD style, otherwise a properly quoted
3956 listing is produced.
3961 has been set twice then the listing is modified to mark out assembled
3964 Otherwise modifies (set and unsets) the given variables.
3965 Arguments are of the form
3967 (no space before or after
3971 if there is no value.
3972 Quotation marks may be placed around any part of the assignment
3973 statement to quote blanks or tabs, e.g.,
3975 .Dl set indentprefix="->"
3977 If an argument begins with
3981 the effect is the same as invoking the
3983 command with the remaining part of the variable
3984 .Pf ( Ql unset save ) .
3990 except that the variables are also exported into the program environment;
3991 since this task requires native host support the command will always
3992 report error if that is not available (but still act like
3995 This operation is a no-op unless all resource files have been loaded.
4001 (sh) Invokes an interactive version of the shell.
4005 Without arguments the list of all currently defined shortcuts is
4007 Otherwise all given arguments (which need not be quoted except for
4008 whitespace) are treated as pairs of shortcuts and their expansions,
4009 creating new or changing already existing shortcuts, as necessary.
4010 Shortcuts may be removed via the command
4012 The expansion strings should be in the syntax that has been described
4021 but performs neither MIME decoding nor decryption, so that the raw
4022 message text is shown.
4026 (si) Shows the size in characters of each message of the given
4031 Shows the current sorting criterion when used without an argument.
4032 Otherwise creates a sorted representation of the current folder,
4035 command and the addressing modes such that they refer to messages in
4037 Message numbers are the same as in regular mode.
4041 a header summary in the new order is also displayed.
4042 Automatic folder sorting can be enabled by setting the
4044 variable, as in, e.g.,
4045 .Ql set autosort=thread .
4046 Possible sorting criterions are:
4048 .Bl -tag -compact -offset indent -width "subject"
4050 Sort the messages by their
4052 field, that is by the time they were sent.
4054 Sort messages by the value of their
4056 field, that is by the address of the sender.
4059 variable is set, the sender's real name (if any) is used.
4061 Sort the messages by their size.
4063 \*(OP Sort the message by their spam score, as has been classified by
4066 Sort the messages by their message status.
4068 Sort the messages by their subject.
4070 Create a threaded display.
4072 Sort messages by the value of their
4074 field, that is by the address of the recipient.
4077 variable is set, the recipient's real name (if any) is used.
4082 (so) The source command reads commands from the given file, which is
4083 subject to the usual filename expansions (see introductional words of
4085 If the given argument ends with a vertical bar
4087 then the argument will instead be interpreted as a shell command and
4088 \*(UA will read the output generated by it.
4094 (beside not supporting pipe syntax a.k.a. shell command input) is that
4095 this command will not generate an error if the given file argument
4096 cannot be opened successfully.
4097 This can matter in, e.g., resource files, since loading of those is
4098 stopped when an error is encountered.
4102 \*(OP Takes a list of messages and clears their
4108 \*(OP Takes a list of messages and causes the
4110 to forget it has ever used them to train its Bayesian filter.
4111 Unless otherwise noted the
4113 flag of the message is inspected to chose wether a message shall be
4121 \*(OP Takes a list of messages and informs the Bayesian filter of the
4125 This also clears the
4127 flag of the messages in question.
4131 \*(OP Takes a list of messages and rates them using the configured
4132 .Va spam-interface ,
4133 without modifying the messages, but setting their
4135 flag as appropriate; because the spam rating headers are lost the rate
4136 will be forgotten once the mailbox is left.
4137 Refer to the manual section
4139 for the complete picture of spam handling in \*(UA.
4143 \*(OP Takes a list of messages and sets their
4149 \*(OP Takes a list of messages and informs the Bayesian filter of the
4155 flag of the messages in question.
4164 Create a threaded representation of the current folder,
4165 i.\|e. indent messages that are replies to other messages in the header
4166 display and change the
4168 command and the addressing modes such that they refer to messages in the
4170 Message numbers are the same as in unthreaded mode.
4174 a header summary in threaded order is also displayed.
4178 (to) Takes a message list and displays the top few lines of each.
4179 The number of lines shown is controlled by the variable
4181 and defaults to five.
4185 (tou) Takes a message list and marks the messages for saving in
4187 \*(UA deviates from the POSIX standard with this command,
4190 command will display the following message instead of the current one.
4196 but also displays out ignored header fields and all parts of MIME
4197 .Ql multipart/alternative
4202 (t) Takes a message list and types out each message on the user's
4208 For MIME multipart messages, all parts with a content type of
4212 are shown, the other are hidden except for their headers.
4213 Messages are decrypted and converted to the terminal character set
4218 Delete all given accounts.
4219 An error message is shown if a given account is not defined.
4222 will discard all existing accounts.
4226 (una) Takes a list of names defined by alias commands
4227 and discards the remembered groups of users.
4230 will discard all existing aliases.
4234 Takes a message list and marks each message as not having been answered.
4238 Only applicable to threaded mode.
4239 Takes a message list and makes the message and all replies to it visible
4240 in header summaries again.
4241 When a message becomes the current message,
4242 it is automatically made visible.
4243 Also when a message with collapsed replies is displayed,
4244 all of these are automatically uncollapsed.
4250 mapping for the given colour type (see
4252 for a list of types) and mapping; if the optional precondition argument
4253 is used then only the exact tuple of mapping and precondition is removed.
4256 will remove all mappings (no precondition allowed).
4258 .Sx "Coloured display"
4259 for the general picture.
4263 Deletes the custom headers given as arguments.
4266 will remove all custom headers.
4270 Undefine all given macros.
4271 An error message is shown if a given macro is not defined.
4274 will discard all existing macros.
4278 (u) Takes a message list and marks each message as not being deleted.
4282 Takes a message list and
4288 Takes a message list and marks each message as not being
4293 Removes the header field names from the list of ignored fields for the
4298 will remove all fields.
4302 Removes the header field names from the list of retained fields for the
4307 will remove all fields.
4311 Remove all the given command
4315 will remove all ghosts.
4319 Removes the header field names from the list of ignored fields.
4322 will remove all fields.
4326 Delete all given MIME types, e.g.,
4327 .Ql unmimetype text/plain
4328 will remove all registered specifications for the MIME type
4332 will discard all existing MIME types, just as will
4334 but which also reenables cache initialization via
4335 .Va mimetypes-load-control .
4339 Forget about all the given mailing lists.
4342 will remove all lists.
4347 .It Ic unmlsubscribe
4348 Remove the subscription attribute from all given mailing lists.
4351 will clear the attribute from all lists which have it set.
4362 Takes a message list and marks each message as not having been read.
4366 Removes the header field names from the list of retained fields.
4369 will remove all fields.
4373 Removes the header field names from the list of ignored fields for
4377 will remove all fields.
4381 Removes the header field names from the list of retained fields for
4385 will remove all fields.
4389 (uns) Takes a list of option names and discards their remembered values;
4397 except that the variables are also removed from the program environment;
4398 since this task requires native host support the command will always
4399 report error if that is not available (but still act like
4402 This operation is a no-op unless all resource files have been loaded.
4408 Deletes the shortcut names given as arguments.
4411 will remove all shortcuts.
4415 Disable sorted or threaded mode
4421 return to normal message order and,
4425 displays a header summary.
4435 Decode the given URL-encoded string arguments and show the results.
4436 Note the resulting strings may not be valid in the current locale, see
4441 URL-encode the given arguments and show the results.
4442 Because the arguments effectively are in the character set of the
4443 current locale the results will vary accordingly unless the input solely
4444 consists of characters in the portable character set, see
4445 .Sx "Character sets" .
4449 Edit the values of or create the given variable(s) in the
4451 Boolean variables cannot be edited.
4455 Show informations about all the given variables.
4456 \*(UA knows about a finite set of known builtin variables that are
4457 subdivided further in boolean and value variants;
4458 they may have special properties, like
4460 (setting may not be changed) and
4462 meaning that the value is generated on-the-fly as necessary.
4463 Beside those known variables an infinite number of unknown, so-called
4465 variables, which are expected to be able to store values, may exist.
4466 .Bd -literal -offset indent
4468 ? varshow sendwait version-major foo bar
4469 "sendwait": (73) boolean: set=1 (ENVIRON=0)
4470 "version-major": (192) value, read-only, virtual:\e
4471 set=1 (ENVIRON=0) value<14>
4472 "foo": (assembled) set=1 (ENVIRON=0) value<bar>
4473 "bar": (assembled) set=0 (ENVIRON=0) value<NULL>
4478 \*(OP Takes a message list and verifies each message.
4479 If a message is not a S/MIME signed message,
4480 verification will fail for it.
4481 The verification process checks if the message was signed using a valid
4483 if the message sender's email address matches one of those contained
4484 within the certificate,
4485 and if the message content has been altered.
4489 (v) Takes a message list and invokes the display editor on each message.
4490 Modified contents are discarded unless the
4496 (w) For conventional messages the body without all headers is written.
4497 The output is decrypted and converted to its native format as necessary.
4498 If the output file exists, the text is appended.
4499 If a message is in MIME multipart format its first part is written to
4500 the specified file as for conventional messages,
4501 and the user is asked for a filename to save each other part.
4502 For convience saving of each part may be skipped by giving an empty value;
4503 the same result can also be achieved by writing it to
4505 For the second and subsequent parts a leading
4507 character causes the part to be piped to the remainder of the user input
4508 interpreted as a shell command;
4509 otherwise the user input is expanded as usually for folders,
4510 e.g., tilde expansion is performed.
4511 In non-interactive mode, only the parts of the multipart message
4512 that have a filename given in the part header are written,
4513 the others are discarded.
4514 The original message is never marked for deletion in the originating
4517 the contents of the destination file are overwritten if the file
4519 No special handling of compressed files is performed.
4528 \*(UA presents message headers in windowfuls as described under the
4531 This command scrolls to the next window of messages.
4532 If an argument is given,
4533 it specifies the window to use.
4534 A number prefixed by
4538 indicates that the window is calculated in relation to the current position.
4539 A number without a prefix specifies an absolute window number,
4542 lets \*(UA scroll to the last window of messages.
4548 but scrolls to the next or previous window that contains at least one
4557 .\" .Sh TILDE ESCAPES {{{
4560 Here is a summary of the tilde escapes,
4561 which are used to perform special functions when composing messages.
4562 Tilde escapes are only recognized at the beginning of lines.
4565 is somewhat of a misnomer since the actual escape character can be
4566 changed by adjusting the option
4569 .Bl -tag -width ".Ic __ filename"
4572 Insert the string of text in the message prefaced by a single
4574 (If the escape character has been changed,
4575 that character must be doubled
4576 in order to send it at the beginning of a line.)
4579 .It Ic ~! Ar command
4580 Execute the indicated shell
4582 then return to the message.
4586 Same effect as typing the end-of-file character.
4589 .It Ic ~: Ar \*(UA-command Ns \0or Ic ~_ Ar \*(UA-command
4590 Execute the given \*(UA command.
4591 Not all commands, however, are allowed.
4595 Write a summary of command escapes.
4598 .It Ic ~< Ar filename
4603 .It Ic ~<! Ar command
4605 is executed using the shell.
4606 Its standard output is inserted into the message.
4609 .It Ic ~@ Op Ar filename...
4610 With no arguments, edit the attachment list interactively.
4611 If an attachment's file name is left empty,
4612 that attachment is deleted from the list.
4613 When the end of the attachment list is reached,
4614 \*(UA will ask for further attachments until an empty name is given.
4615 If a given file name solely consists of the number sign
4617 followed by a valid message number of the currently active mailbox, then
4618 the given message is attached as a MIME
4620 and the rest of this section does not apply.
4622 If character set conversion has been compiled into \*(UA, then this mode
4623 gives the user the option to specify input and output character sets,
4624 unless the file extension indicates binary content, in which case \*(UA
4625 asks wether this step shall be skipped for the attachment in question.
4626 If not skipped, then the charset that succeeds to represent the
4627 attachment data will be used in the
4629 MIME parameter of the mail message:
4631 .Bl -bullet -compact
4633 If input and output character sets are specified, then the conversion is
4634 performed on the fly.
4635 The user will be asked repeatedly until the desired conversion succeeds.
4637 If only an output character set is specified, then the input is assumed
4640 charset and will be converted to the given output charset on the fly.
4641 The user will be asked repeatedly until the desired conversion succeeds.
4643 If no character sets are specified at all then the algorithm that is
4644 documented in the section
4645 .Sx "Character sets"
4646 is applied, but directly and on the fly.
4647 The user will be asked repeatedly until the desired conversion succeeds.
4649 Finally, if an input-, but no output character set is specified, then no
4650 conversion is ever performed, but the
4652 MIME parameter value will still be set to the user input.
4654 The character set selection loop can be left by typing
4656 i.e., causing an interrupt.
4657 .\" \*(OU next sentence
4658 Note that before \*(UA version 15.0 this terminates the entire
4659 current attachment selection, not only the character set selection.
4662 Without character set conversion support, \*(UA will ask for the input
4663 character set only, and it'll set the
4665 MIME parameter value to the given input, if any;
4666 if no user input is seen then the
4668 character set will be used for the parameter value instead.
4669 Note that the file extension check isn't performed in this mode, since
4670 no conversion will take place anyway.
4672 Note that in non-interactive mode, for reproduceabilities sake, there
4673 will always be two questions for each attachment, regardless of wether
4674 character set conversion is available and what the file extension is.
4675 The first asks for the filename, and the second asks for the input
4676 character set to be passed through to the corresponding MIME parameter;
4677 no conversion will be tried if there is input to the latter question,
4678 otherwise the usual conversion algorithm, as above, is applied.
4679 For message attachments, the answer to the second question is completely
4684 arguments are specified for the
4686 command they are treated as a comma-separated list of files,
4687 which are all expanded and appended to the end of the attachment list.
4688 (Commas need to be escaped with backslash, but filenames with leading or
4689 trailing whitespace can only be added via the command line or the first
4691 Message attachments can only be added via the first method;
4692 filenames which clash with message numbers can only be added via the
4693 command line or the second method.)
4694 In this mode the (text) attachments are assumed to be in
4696 encoding, and will be evaluated as documented in the section
4697 .Sx "Character sets" .
4701 Inserts the string contained in the
4704 .Ql Ic ~i Ns \0Sign ) .
4705 The escape sequences tabulator
4713 Inserts the string contained in the
4716 .Ql Ic ~i Ns \0sign ) .
4717 The escape sequences tabulator
4724 .It Ic ~b Ar name ...
4725 Add the given names to the list of blind carbon copy recipients.
4728 .It Ic ~c Ar name ...
4729 Add the given names to the list of carbon copy recipients.
4733 Read the file specified by the
4735 variable into the message.
4739 Invoke the text editor on the message collected so far.
4740 After the editing session is finished,
4741 the user may continue appending text to the message.
4744 .It Ic ~F Ar messages
4745 Read the named messages into the message being sent, including all
4746 message headers and MIME parts.
4747 If no messages are specified, read in the current message.
4750 .It Ic ~f Ar messages
4751 Read the named messages into the message being sent.
4752 If no messages are specified, read in the current message.
4756 lists are used to modify the message headers.
4757 For MIME multipart messages,
4758 only the first displayable part is included.
4762 Edit the message header fields
4767 by typing each one in turn and allowing the user to edit the field.
4768 The default values for these fields originate from the
4776 Edit the message header fields
4782 by typing each one in turn and allowing the user to edit the field.
4785 .It Ic ~i Ar variable
4786 Insert the value of the specified variable into the message,
4787 adding a newline character at the end.
4788 The message remains unaltered if the variable is unset or empty.
4789 The escape sequences tabulator
4796 .It Ic ~M Ar messages
4797 Read the named messages into the message being sent,
4800 If no messages are specified, read the current message.
4803 .It Ic ~m Ar messages
4804 Read the named messages into the message being sent,
4807 If no messages are specified, read the current message.
4811 lists are used to modify the message headers.
4812 For MIME multipart messages,
4813 only the first displayable part is included.
4817 Display the message collected so far,
4818 prefaced by the message header fields
4819 and followed by the attachment list, if any.
4823 Abort the message being sent,
4824 copying it to the file specified by the
4831 .It Ic ~R Ar filename
4832 Read the named file into the message, indented by
4836 .It Ic ~r Ar filename
4837 Read the named file into the message.
4841 Cause the named string to become the current subject field.
4844 .It Ic ~t Ar name ...
4845 Add the given name(s) to the direct recipient list.
4848 .It Ic ~U Ar messages
4849 Read in the given / current message(s) excluding all headers, indented by
4853 .It Ic ~u Ar messages
4854 Read in the given / current message(s), excluding all headers.
4858 Invoke an alternate editor (defined by the
4860 option) on the message collected so far.
4861 Usually, the alternate editor will be a screen editor.
4862 After the editor is quit,
4863 the user may resume appending text to the end of the message.
4866 .It Ic ~w Ar filename
4867 Write the message onto the named file.
4869 the message is appended to it.
4875 except that the message is not saved at all.
4878 .It Ic ~| Ar command
4879 Pipe the message through the specified filter command.
4880 If the command gives no output or terminates abnormally,
4881 retain the original text of the message.
4884 is often used as a rejustifying filter.
4889 .\" .Sh INTERNAL VARIABLES {{{
4890 .Sh "INTERNAL VARIABLES"
4892 Internal \*(UA variables are controlled via the
4896 commands; prefixing a variable name with the string
4900 has the same effect as using
4906 Creation or editing of variables can be performed in the
4911 will give more insight on the given variable(s), and
4913 when called without arguments, will show a listing of all variables.
4914 Variables are also implicitly inherited from the program
4916 and can be set explicitly via the command line option
4920 Two different kind of variables exist.
4921 There are boolean variables, which can only be in one of the two states
4925 and value variables with a(n optional) string value.
4926 For the latter proper quoting is necessary upon assignment time:
4927 To embed whitespace (space and tabulator) in a value it either needs to
4928 be escaped with a backslash character, or the entire value must be
4929 enclosed in (double or single) quotation marks;
4930 To use quotation marks identical to those used to enclose the value,
4931 escape them with a backslash character.
4932 The backslash character has no special meaning except in these cases.
4934 .Bd -literal -offset indent
4935 set one=val\e 1 two="val 2" \e
4936 three='val "3"' four='val \e'4\e''
4937 varshow one two three four
4938 unset one two three four
4942 Dependent upon the actual option the string values will be interpreted
4943 as numbers, colour names, normal text etc., but there also exists
4944 a special kind of string value, the
4945 .Dq boolean string ,
4946 which must either be a decimal integer (in which case
4950 and any other value is true) or any of the (case-insensitive) strings
4955 for a false boolean and
4960 for a true boolean; a special kind of boolean string is the
4962 which is a boolean string that can optionally be prefixed with the
4963 (case-insensitive) term
4967 which causes prompting of the user in interactive mode, with the given
4968 boolean as the default value.
4970 .\" .Ss "Initial settings" {{{
4971 .\" (Keep in SYNC: ./main.c:_startup(), ./nail.rc, ./nail.1:"Initial settings"!)
4972 .Ss "Initial Settings"
4974 The standard POSIX 2008/Cor 1-2013 mandates the following initial
4980 .Pf no Va autoprint ,
4994 .Pf no Va ignoreeof ,
4996 .Pf no Va keepsave ,
4998 .Pf no Va outfolder ,
5003 (note that \*(UA deviates from the standard by using
5007 special prompt escape results in
5015 .Pf no Va sendwait ,
5024 Notes: \*(UA doesn't support the
5026 variable \(en use command line options or
5027 .Va sendmail-arguments
5028 to pass options through to a MTA.
5029 And the default global
5031 file (which is loaded unless the
5033 command line flag has been used or the
5034 .Ev NAIL_NO_SYSTEM_RC
5035 environment variable is set) bends those initial settings a bit, e.g.,
5036 it sets the variables
5041 to name a few, calls
5043 etc., and should thus be taken into account.
5046 .\" .Ss "Variables" {{{
5049 .Bl -tag -width ".It Va _utoprin_"
5051 .It Va add-file-recipients
5052 \*(BO When file or pipe recipients have been specified,
5053 mention them in the corresponding address fields of the message instead
5054 of silently stripping them from their recipient list.
5055 By default such addressees are not mentioned.
5057 .Mx Va agent-shell-lookup
5058 .It Va agent-shell-lookup-USER@HOST , agent-shell-lookup-HOST , \
5060 \*(IN\*(OP Account passwords can be fetched via an external agent
5061 program in order to permit encrypted password storage \(en see
5062 .Sx "On URL syntax and credential lookup"
5063 for more on credential lookup.
5064 If this is set then the content is interpreted as a shell command the
5065 output of which (with newline characters removed) is treated as the
5066 account password shall the command succeed (and have produced non-empty
5067 non-newline output); e.g., via
5069 .Bd -literal -offset indent
5070 $ echo PASSWORD > .pass
5072 $ eval `gpg-agent --daemon \e
5073 --pinentry-program=/usr/bin/pinentry-curses \e
5074 --max-cache-ttl 99999 --default-cache-ttl 99999`
5075 $ echo 'set agent-shell-lookup="gpg -d .pass.gpg"' \e
5079 A couple of environment variables will be set for the agent:
5081 .Bl -tag -compact -width ".It Ev _AIL_TMPDIR[337]"
5083 The temporary directory that \*(UA uses.
5084 Usually identical to
5086 but guaranteed to be set and usable by child processes;
5087 to ensure the latter condition for
5093 for which the password is looked up.
5094 .It Ev NAIL_USER_ENC
5095 The URL percent-encoded variant of
5098 The plain machine hostname of the user account.
5099 .It Ev NAIL_HOST_PORT
5102 (hostname possibly including port) of the user account.
5107 \*(BO Causes only the local part to be evaluated
5108 when comparing addresses.
5112 \*(BO Causes messages saved in
5114 to be appended to the end rather than prepended.
5115 This should always be set.
5119 \*(BO Causes \*(UA to prompt for the subject of each message sent.
5120 If the user responds with simply a newline,
5121 no subject field will be sent.
5125 \*(BO Causes the prompts for
5129 lists to appear after the message has been edited.
5133 \*(BO If set, \*(UA asks for files to attach at the end of each message,
5134 shall the list be found empty at that time.
5135 An empty line finalizes the list.
5139 \*(BO Causes the user to be prompted for carbon copy recipients
5140 (at the end of each message if
5144 are set) shall the list be found empty (at that time).
5145 An empty line finalizes the list.
5149 \*(BO Causes the user to be prompted for blind carbon copy
5150 recipients (at the end of each message if
5154 are set) shall the list be found empty (at that time).
5155 An empty line finalizes the list.
5159 \*(BO\*(OP Causes the user to be prompted if the message is to be
5160 signed at the end of each message.
5163 variable is ignored when this variable is set.
5167 \*(BO Alternative name for
5174 .It Va attachment-ask-content-description , \
5175 attachment-ask-content-disposition , \
5176 attachment-ask-content-id , \
5177 attachment-ask-content-type
5178 \*(BO If set then the user will be prompted for some attachment
5179 information when editing the attachment list.
5180 It is advisable to not use these but for the first of the variables;
5181 even for that it has to be noted that the data is used
5187 A sequence of characters to display in the
5191 as shown in the display of
5193 each for one type of messages (see
5194 .Sx "Message states" ) ,
5195 with the default being
5198 .Ql NU\ \ *HMFAT+\-$~
5201 variable is set, in the following order:
5203 .Bl -tag -compact -offset indent -width ".It Ql _"
5225 start of a collapsed thread.
5227 an uncollapsed thread (TODO ignored for now).
5231 classified as possible spam.
5237 Specifies a list of recipients to which a blind carbon copy of each
5238 outgoing message will be sent automatically.
5242 Specifies a list of recipients to which a carbon copy of each outgoing
5243 message will be sent automatically.
5247 \*(BO Causes threads to be collapsed automatically when threaded mode
5254 \*(BO Causes the delete command to behave like
5256 thus, after deleting a message the next one will be typed automatically.
5260 \*(BO\*(OB Causes threaded mode (see the
5262 command) to be entered automatically when a folder is opened.
5264 .Ql autosort=thread .
5268 Causes sorted mode (see the
5270 command) to be entered automatically with the value of this option as
5271 sorting method when a folder is opened, e.g.,
5272 .Ql set autosort=thread .
5276 \*(BO Enables the substitution of
5278 by the contents of the last command line in shell escapes.
5281 .It Va batch-exit-on-error
5282 \*(BO If the batch mode has been enabled via the
5284 command line option, then this variable will be consulted whenever \*(UA
5285 completes one operation (returns to the command prompt); if it is set
5286 then \*(UA will terminate if the last operation generated an error.
5290 \*(BO Causes automatic display of a header summary after executing a
5296 \*(BO Sets some cosmetical features to traditional BSD style;
5297 has the same affect as setting
5299 and all other variables prefixed with
5301 it also changes the meaning of the \*(UA specific
5304 escape sequence and changes behaviour of
5306 (which doesn't exist in BSD).
5310 \*(BO Changes the letters shown in the first column of a header
5311 summary to traditional BSD style.
5315 \*(BO Changes the display of columns in a header summary to traditional
5320 \*(BO Changes some informational messages to traditional BSD style.
5326 field to appear immediately after the
5328 field in message headers and with the
5330 .Sx "TILDE ESCAPES" .
5334 \*(BO Changes the output format of the
5336 command to traditional BSD style.
5340 The value that should appear in the
5344 MIME header fields when no character set conversion of the message data
5346 This defaults to US-ASCII, and the chosen character set should be
5347 US-ASCII compatible.
5351 \*(OP The default 8-bit character set that is used as an implicit last
5352 member of the variable
5354 This defaults to UTF-8.
5355 If no character set conversion capabilities are available in \*(UA then
5356 the only supported character set is
5358 Refer to the section
5359 .Sx "Character sets"
5360 for the complete picture of character set conversion in \*(UA.
5363 .It Va charset-unknown-8bit
5364 \*(OP RFC 1428 specifies conditions when internet mail gateways shall
5366 the content of a mail message by using a character set with the name
5368 Because of the unclassified nature of this character set \*(UA will not
5369 be capable to convert this character set to any other character set.
5370 If this variable is set any message part which uses the character set
5372 is assumed to really be in the character set given in the value,
5373 otherwise the (final) value of
5375 is used for this purpose.
5377 This variable will also be taken into account if a MIME type (see
5378 .Sx "The mime.types files" )
5379 of a MIME message part that uses the
5381 character set is forcefully treated as text.
5385 The default value for the
5390 .It Va colour-disable
5391 \*(BO\*(OP Forcefully disable usage of colours.
5392 Also see the section
5393 .Sx "Coloured display" .
5397 \*(BO\*(OP Wether colour shall be used for output that is paged through
5399 Note that pagers may need special flags, e.g.,
5407 in order to support colours; therefore \*(UA will inspect the variable
5409 \(en if that starts with the string
5411 a non-existing environment variable
5418 will optionally be set to
5420 Also see the section
5421 .Sx "Coloured display"
5426 \*(OP A comma-separated list of
5428 inals for which coloured display can be used.
5429 Entries only need to be added if the string
5431 isn't part of the terminal name itself; the default value is
5433 .\" (Keep in SYNC: ./nail.h:n_COLOUR_TERMS, ./nail.1:*colour-terms*"!)
5434 .Dl aterm,cons25,gnome,konsole,\:kterm,\:linux,\:\
5435 rxvt,\:rxvt-unicode,\:screen,\:sun,\:vt100,\:vt220,\:wsvt25,\:xterm
5439 In a(n interactive) terminal session, then if this valued option is set
5440 it'll be used as a threshold to determine how many lines the given
5441 output has to span before it will be displayed via the configured
5445 can be forced by setting this to the value
5447 setting it without a value will deduce the current height of the
5448 terminal screen to compute the treshold (see
5456 \*(OB A variable counterpart of the
5458 command (see there for documentation), interpreted as a comma-separated
5459 list of custom headers to be injected, to include commas in the header
5460 bodies escape them with backslash, e.g.:
5462 .Dl set customhdr="Hdr1: Body1-1\e, Body1-2, Hdr2: Body2"
5468 the message date, if any is to be displayed according to the format of
5470 is by default taken from the
5472 line of the message.
5473 If this variable is set the date as given in the
5475 header field is used instead, converted to local time.
5476 To control the display format of the date assign a valid
5481 format should not be used, because \*(UA doesn't take embedded newlines
5482 into account when calculating how many lines fit onto the screen.)
5484 .Va datefield-markout-older .
5487 .It Va datefield-markout-older
5488 This option, when set in addition to
5492 messages (concept is rather comparable to the
5494 option of the POSIX utility
5496 The content interpretation is identical to
5501 \*(BO Enables debug messages and obsoletion warnings, disables the
5502 actual delivery of messages and also implies
5508 .It Va disposition-notification-send
5510 .Ql Disposition-Notification-To:
5511 header (RFC 3798) with the message.
5515 .\" TODO .It Va disposition-notification-send-HOST
5517 .\".Va disposition-notification-send
5518 .\" for SMTP accounts on a specific host.
5519 .\" TODO .It Va disposition-notification-send-USER@HOST
5521 .\".Va disposition-notification-send
5522 .\"for a specific account.
5526 \*(BO When dot is set, a period
5528 on a line by itself during message input in (interactive) compose mode
5529 will be treated as end-of-message (in addition to the normal end-of-file
5538 .It Va dotlock-ignore-error
5539 \*(BO\*(OP Synchronization of mailboxes which \*(UA treats as system
5540 mailboxes (see the command
5542 will be protected with so-called dotlock files\(emthe traditional mail
5543 spool file locking method\(emin addition to system file locking.
5544 Because \*(UA ships with a privilege-separated dotlock creation program
5545 that should always be able to create such a dotlock file there is no
5546 good reason to ignore dotlock file creation errors, and thus these are
5547 fatal unless this variable is set.
5551 \*(BO If this variable is set then the editor is started automatically
5552 when a message is composed in interactive mode, as if the
5558 variable is implied for this automatically spawned editor session.
5562 \*(BO When a message is edited while being composed,
5563 its header is included in the editable text.
5573 fields are accepted within the header, other fields are ignored.
5577 \*(BO When entering interactive mode \*(UA normally writes
5578 .Dq \&No mail for user
5579 and exits immediately if a mailbox is empty or doesn't exist.
5580 If this option is set \*(UA starts even with an empty or nonexistent
5581 mailbox (the latter behaviour furtherly depends upon
5587 Suggestion for the MIME encoding to use in outgoing text messages
5589 Valid values are the default
5590 .Ql quoted-printable ,
5595 may cause problems when transferring mail messages over channels that
5596 are not ESMTP (RFC 1869) compliant.
5597 If there is no need to encode a message,
5599 transfer mode is always used regardless of this variable.
5600 Binary data is always encoded as
5605 If defined, the first character of this option
5606 gives the character to use in place of
5609 .Sx "TILDE ESCAPES" .
5613 If not set then file and command pipeline targets are not allowed,
5614 and any such address will be filtered out, giving a warning message.
5615 If set without a value then all possible recipient address
5616 specifications will be accepted \(en see the section
5617 .Sx "On sending mail, and non-interactive mode"
5619 To accept them, but only in interactive mode, or when tilde commands
5620 were enabled explicitly by using one of the command line options
5624 set this to the (case-insensitive) value
5626 (note right now this is actually like setting
5627 .Ql restrict,-all,+name,+addr ) .
5629 In fact the value is interpreted as a comma-separated list of values.
5632 then the existence of disallowed specifications is treated as a hard
5633 send error instead of only filtering them out.
5634 The remaining values specify wether a specific type of recipient
5635 address specification is allowed (optionally indicated by a plus sign
5637 prefix) or disallowed (prefixed with a hyphen
5641 addresses all possible address specifications,
5645 command pipeline targets,
5647 plain user names and (MTA) aliases (\*(OB
5649 may be used as an alternative syntax to
5654 These kind of values are interpreted in the given order, so that
5655 .Ql restrict,\:fail,\:+file,\:-all,\:+addr
5656 will cause hard errors for any non-network address recipient address
5657 unless \*(UA is in interactive mode or has been started with the
5661 command line option; in the latter case(s) any address may be used, then.
5665 Unless this variable is set additional mail-transfer-agent (MTA)
5666 arguments from the command line, as can be given after a
5668 separator, are ignored due to safety reasons.
5669 However, if set to the special (case-insensitive) value
5671 then the presence of additional MTA arguments is treated as a hard
5672 error that causes \*(UA to exit with failure status.
5673 A lesser strict variant is the otherwise identical
5675 which does accept such arguments in interactive mode, or if tilde
5676 commands were enabled explicitly by using one of the command line options
5683 \*(RO Information on the features compiled into \*(UA \(en the content
5684 of this variable is identical to the output of the command
5689 \*(BO This option reverses the meanings of a set of reply commands,
5690 turning the lowercase variants, which by default address all recipients
5691 included in the header of a message
5692 .Pf ( Ic reply , respond , followup )
5693 into the uppercase variants, which by default address the sender only
5694 .Pf ( Ic Reply , Respond , Followup )
5697 .Ic replysender , respondsender , followupsender
5699 .Ic replyall , respondall , followupall
5700 are not affected by the current setting of
5705 .It Va file-hook-load-EXTENSION , file-hook-save-EXTENSION
5706 It is possible to install file hooks which will be used by the
5708 command in order to be able to transparently handle (through an
5709 intermediate temporary file) files with specific
5711 s: the variable values can include shell snippets and are expected to
5712 write data to standard output / read data from standard input,
5714 \*(ID The variables may not be changed while there is a mailbox
5716 .Bd -literal -offset indent
5717 set file-hook-load-xy='echo >&2 XY-LOAD; gzip -cd' \e
5718 file-hook-save-xy='echo >&2 XY-SAVE; gzip -c' \e
5719 record=+null-sent.xy
5724 The name of the directory to use for storing folders of messages.
5725 All folder names that begin with
5727 refer to files below it.
5728 The same special conventions as documented for the
5730 command may be used when specifying a new value for
5732 but be aware that the expansion is fully performed immediately.
5736 This variable can be set to the name of a
5738 macro which will be called whenever a
5741 The macro will also be invoked when new mail arrives,
5742 but message lists for commands executed from the macro
5743 only include newly arrived messages then.
5745 are activated by default in a folder hook, causing the covered settings
5746 to be reverted once the folder is left again.
5749 Macro behaviour, including option localization, will change in v15.
5750 Please be aware of that and possibly embed a version check in a resource
5754 .It Va folder-hook-FOLDER
5759 Unlike other folder specifications, the fully expanded name of a folder,
5760 without metacharacters, is used to avoid ambiguities.
5761 However, if the mailbox resides under
5765 specification is tried in addition, e.g., if
5769 (and thus relative to the user's home directory) then
5770 .Pa /home/usr1/mail/sent
5772 .Ql folder-hook-/home/usr1/mail/sent
5773 first, but then followed by
5774 .Ql folder-hook-+sent .
5778 \*(BO Controls wether a
5779 .Ql Mail-Followup-To:
5780 header is generated when sending messages to known mailing lists.
5782 .Va followup-to-honour
5784 .Ic mlist , mlsubscribe , reply
5789 .It Va followup-to-honour
5791 .Ql Mail-Followup-To:
5792 header is honoured when group-replying to a message via
5796 This is a quadoption; if set without a value it defaults to
5806 .It Va forward-as-attachment
5807 \*(BO Original messages are normally sent as inline text with the
5810 and only the first part of a multipart message is included.
5811 With this option messages are sent as unmodified MIME
5813 attachments with all of their parts included.
5817 The address (or a list of addresses) to put into the
5819 field of the message header, quoting RFC 5322:
5820 the author(s) of the message, that is, the mailbox(es) of the person(s)
5821 or system(s) responsible for the writing of the message.
5822 If replying to messages these addresses are handled as if they were in
5826 If the machine's hostname is not valid at the Internet (for example at
5827 a dialup machine) then either this variable or
5832 adds even more fine-tuning capabilities),
5836 contains more than one address,
5839 variable is required (according to the standard RFC 5322).
5843 \*(BO When replying to or forwarding a message \*(UA normally removes
5844 the comment and name parts of email addresses.
5845 If this variable is set such stripping is not performed,
5846 and comments, names etc. are retained.
5850 The string to put before the text of a message with the
5854 .Va forward-as-attachment
5857 .Dq -------- Original Message --------
5858 if unset; No heading is put if it is set to the empty string.
5862 \*(BO Causes the header summary to be written at startup and after
5863 commands that affect the number of messages or the order of messages in
5864 the current folder; enabled by default.
5865 The command line option
5873 A format string to use for the summary of
5875 similar to the ones used for
5878 Format specifiers in the given string start with a percent character
5880 and may be followed by an optional decimal number indicating the field
5881 width \(em if that is negative, the field is to be left-aligned.
5882 Valid format specifiers are:
5885 .Bl -tag -compact -offset indent -width "_%%_"
5887 A plain percent character.
5890 a space character but for the current message
5892 for which it expands to
5896 a space character but for the current message
5898 for which it expands to
5901 \*(OP The spam score of the message, as has been classified via the
5904 Shows only a replacement character if there is no spam support.
5906 Message attribute character (status flag); the actual content can be
5910 The date when the message was received, or the date found in the
5914 variable is set (optionally to a date display format string).
5916 The indenting level in threaded mode.
5918 The address of the message sender.
5920 The message thread tree structure.
5921 (Note that this format doesn't support a field width.)
5923 The number of lines of the message, if available.
5927 The number of octets (bytes) in the message, if available.
5929 Message subject (if any).
5931 Message subject (if any) in double quotes.
5933 Message recipient flags: is the addressee of the message a known or
5934 subscribed mailing list \(en see
5939 The position in threaded/sorted order.
5943 .Ql %>\&%a\&%m\ %-18f\ %16d\ %4l/%\-5o\ %i%-s ,
5945 .Ql %>\&%a\&%m\ %20-f\ \ %16d\ %3l/%\-5o\ %i%-S
5956 .It Va headline-bidi
5957 Bidirectional text requires special treatment when displaying headers,
5958 because numbers (in dates or for file sizes etc.) will not affect the
5959 current text direction, in effect resulting in ugly line layouts when
5960 arabic or other right-to-left text is to be displayed.
5961 On the other hand only a minority of terminals is capable to correctly
5962 handle direction changes, so that user interaction is necessary for
5964 Note that extended host system support is required nonetheless, e.g.,
5965 detection of the terminal character set is one precondition;
5966 and this feature only works in an Unicode (i.e., UTF-8) locale.
5968 In general setting this variable will cause \*(UA to encapsulate text
5969 fields that may occur when displaying
5971 (and some other fields, like dynamic expansions in
5973 with special Unicode control sequences;
5974 it is possible to fine-tune the terminal support level by assigning
5976 no value (or any value other than
5981 will make \*(UA assume that the terminal is capable to properly deal
5982 with Unicode version 6.3, in which case text is embedded in a pair of
5983 U+2068 (FIRST STRONG ISOLATE) and U+2069 (POP DIRECTIONAL ISOLATE)
5985 In addition no space on the line is reserved for these characters.
5987 Weaker support is chosen by using the value
5989 (Unicode 6.3, but reserve the room of two spaces for writing the control
5990 sequences onto the line).
5995 select Unicode 1.1 support (U+200E, LEFT-TO-RIGHT MARK); the latter
5996 again reserves room for two spaces in addition.
6000 \*(OP If a command line editor is available then this can be set to
6001 name the (expandable) path of the location of a permanent history file.
6004 .It Va history-gabby
6005 \*(BO\*(OP Add more entries to the history as is normally done.
6008 .It Va history-gabby-persist
6009 \*(BO\*(OP \*(UA's own MLE will not save the additional
6011 entries in persistent storage unless this variable is set.
6012 On the other hand it will not loose the knowledge of wether a persistent
6013 entry was gabby or not.
6019 \*(OP If a command line editor is available this value restricts the
6020 amount of history entries that are saved into a set and valid
6022 A value of less than 0 disables this feature;
6023 note that loading and incorporation of
6025 upon program startup can also be suppressed by doing this.
6026 An unset or invalid value, or 0, causes a default value to be used.
6027 Dependent on the available command line editor this will also define the
6028 number of history entries in memory;
6029 it is also editor-specific wether runtime updates of this value will be
6034 \*(BO This option is used to hold messages in the system mailbox,
6035 and it is set by default.
6039 Use this string as hostname when expanding local addresses instead of
6040 the value obtained from
6051 transport is not used then it is normally the responsibility of the MTA
6052 to create these fields, \*(IN in conjunction with
6056 also influences the results;
6057 you should produce some test messages with the desired combination of
6066 \*(BO\*(OP Can be used to turn off the automatic conversion of domain
6067 names according to the rules of IDNA (internationalized domain names
6069 Since the IDNA code assumes that domain names are specified with the
6071 character set, an UTF-8 locale charset is required to represent all
6072 possible international domain names (before conversion, that is).
6076 \*(BO Ignore interrupt signals from the terminal while entering
6077 messages; instead echo them as
6079 characters and discard the current line.
6083 \*(BO Ignore end-of-file conditions
6084 .Pf ( Ql control-D )
6085 in compose mode on message input and in interactive command input.
6086 If set an interactive command input session can only be left by
6087 explicitly using one of the commands
6091 and message input in compose mode can only be terminated by entering
6094 on a line by itself or by using the
6096 .Sx "TILDE ESCAPES" ;
6098 overrides a setting of
6110 option for indenting messages,
6111 in place of the normal tabulator character
6113 which is the default.
6114 Be sure to quote the value if it contains spaces or tabs.
6118 \*(BO If set, an empty mailbox file is not removed.
6119 This may improve the interoperability with other mail user agents
6120 when using a common folder directory, and prevents malicious users
6121 from creating fake mailboxes in a world-writable spool directory.
6122 Note this only applies to local regular (MBOX) files, other mailbox
6123 types will never be removed.
6126 .It Va keep-content-length
6127 \*(BO When (editing messages and) writing
6129 mailbox files \*(UA can be told to keep the
6133 header fields that some MUAs generate by setting this variable.
6134 Since \*(UA does neither use nor update these non-standardized header
6135 fields (which in itself shows one of their conceptual problems),
6136 stripping them should increase interoperability in between MUAs that
6137 work with with same mailbox files.
6138 Note that, if this is not set but
6139 .Va writebackedited ,
6140 as below, is, a possibly performed automatic stripping of these header
6141 fields already marks the message as being modified.
6145 \*(BO When a message is saved it is usually discarded from the
6146 originating folder when \*(UA is quit.
6147 Setting this option causes all saved message to be retained.
6150 .It Va line-editor-cursor-right
6151 \*(OP If the builtin command line editor is used, actions which are
6152 based on rightwise movement may not work on some terminals.
6153 If you encounter such problems, set this variable to the terminal
6154 control sequence that is necessary to move the cursor one column to the
6158 which should work for most terminals.
6165 and other control character have to be written as shell-style escape
6172 .It Va line-editor-disable
6173 \*(BO Turn off any enhanced line editing capabilities (see
6174 .Sx "Command line editor"
6179 \*(BO When a message is replied to and this variable is set,
6180 it is marked as having been answered.
6181 This mark has no technical meaning in the mail system;
6182 it just causes messages to be marked in the header summary,
6183 and makes them specially addressable.
6187 \*(BO \*(UA generates and expects fully RFC 4155 compliant MBOX text
6189 Messages which are fetched over the network or from within already
6190 existing Maildir (or any non-MBOX) mailboxes may require so-called
6192 quoting (insertion of additional
6194 characters to prevent line content misinterpretation) to be applied in
6195 order to be storable in MBOX mailboxes, however, dependent on the
6196 circumspection of the message producer.
6197 (E.g., \*(UA itself will, when newly generating messages, choose a
6198 .Pf Content-Transfer- Va encoding
6199 that prevents the necessity for such quoting \(en a necessary
6200 precondition to ensure message checksums won't change.)
6202 By default \*(UA will perform this
6204 quoting in a way that results in a MBOX file that is compatible with
6205 the POSIX MBOX layout, which means that, in order not to exceed the
6206 capabilities of simple applications, many more
6208 lines get quoted (thus modified) than necessary according to RFC 4155.
6209 Set this option to instead generate MBOX files which comply to RFC 4155.
6213 \*(BO Internal development variable.
6216 .It Va message-id-disable
6217 \*(BO By setting this option the generation of
6219 can be completely suppressed, effectively leaving this task up to the
6220 mail-transfer-agent (MTA) or the SMTP server.
6221 (According to RFC 5321 your SMTP server is not required to add this
6222 field by itself, so you should ensure that it accepts messages without a
6226 .It Va message-inject-head
6227 A string to put at the beginning of each new message.
6228 The escape sequences tabulator
6235 .It Va message-inject-tail
6236 A string to put at the end of each new message.
6237 The escape sequences tabulator
6245 \*(BO Usually, when an
6247 expansion contains the sender, the sender is removed from the expansion.
6248 Setting this option suppresses these removals.
6253 option to be passed to mail-transfer-agents (MTAs);
6254 though most of the modern MTAs don't (no longer) document this flag, no
6255 MTA is known which doesn't support it (for historical compatibility).
6258 .It Va mime-allow-text-controls
6259 \*(BO When sending messages, each part of the message is MIME-inspected
6260 in order to classify the
6263 .Ql Content-Transfer-Encoding:
6266 that is required to send this part over mail transport, i.e.,
6267 a computation rather similar to what the
6269 command produces when used with the
6273 This classification however treats text files which are encoded in
6274 UTF-16 (seen for HTML files) and similar character sets as binary
6275 octet-streams, forcefully changing any
6280 .Ql application/octet-stream :
6281 If that actually happens a yet unset charset MIME parameter is set to
6283 effectively making it impossible for the receiving MUA to automatically
6284 interpret the contents of the part.
6286 If this option is set, and the data was unambiguously identified as text
6287 data at first glance (by a
6291 file extension), then the original
6293 will not be overwritten.
6296 .It Va mime-alternative-favour-rich
6297 \*(BO If this variable is set then rich MIME alternative parts (e.g.,
6298 HTML) will be preferred in favour of included plain text versions when
6299 displaying messages, provided that a handler exists which produces
6300 output that can be (re)integrated into \*(UA's normal visual display.
6301 (E.g., at the time of this writing some newsletters ship their full
6302 content only in the rich HTML part, whereas the plain text part only
6303 contains topic subjects.)
6306 .It Va mime-counter-evidence
6309 field is used to decide how to handle MIME parts.
6310 Some MUAs however don't use
6312 or a similar mechanism to correctly classify content, but simply specify
6313 .Ql application/octet-stream ,
6314 even for plain text attachments like
6316 If this variable is set then \*(UA will try to classify such MIME
6317 message parts on its own, if possible, for example via a possibly
6318 existent attachment filename.
6319 A non-empty value may also be given, in which case a number is expected,
6320 actually a carrier of bits.
6321 Creating the bit-carrying number is a simple addition:
6322 .Bd -literal -offset indent
6323 ? !echo Value should be set to $((2 + 4 + 8))
6324 Value should be set to 14
6327 .Bl -bullet -compact
6329 If bit two is set (2) then the detected
6331 content-type will be carried along with the message and be used for
6333 .Va pipe-TYPE/SUBTYPE
6334 is responsible for the MIME part, shall that question arise;
6335 when displaying such a MIME part the part-info will indicate the
6336 overridden content-type by showing a plus-sign
6339 If bit three is set (4) then the counter-evidence is always produced
6340 and a positive result will be used as the MIME type, even forcefully
6341 overriding the parts given MIME type.
6343 If bit four is set (8) then as a last resort the actual content of
6344 .Ql application/octet-stream
6345 parts will be inspected, so that data which looks like plain text can be
6350 .It Va mimetypes-load-control
6351 This option can be used to control which of the
6353 databases are loaded by \*(UA, as furtherly described in the section
6354 .Sx "The mime.types files" .
6357 is part of the option value, then the user's personal
6359 file will be loaded (if it exists); likewise the letter
6361 controls loading of the system wide
6362 .Pa /etc/mime.types ;
6363 directives found in the user file take precedence, letter matching is
6365 If this option is not set \*(UA will try to load both files.
6366 Incorporation of the \*(UA-builtin MIME types cannot be suppressed,
6367 but they will be matched last.
6369 More sources can be specified by using a different syntax: if the
6370 value string contains an equals sign
6372 then it is instead parsed as a comma-separated list of the described
6375 pairs; the given filenames will be expanded and loaded, and their
6376 content may use the extended syntax that is described in the section
6377 .Sx "The mime.types files" .
6378 Directives found in such files always take precedence (are prepended to
6379 the MIME type cache).
6382 .It Va NAIL_EXTRA_RC
6383 The name of an optional startup file to be read last.
6384 This variable has an effect only if it is set in any of the
6385 .Sx "Resource files" ,
6386 it is not imported from the environment.
6387 Use this file for commands that are not understood by other POSIX
6392 .It Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup
6393 \*(BO\*(IN\*(OP Used to control usage of the users
6395 file for lookup of account credentials, as documented in the section
6396 .Sx "On URL syntax and credential lookup"
6400 .Sx "The .netrc file"
6401 documents the file format.
6405 If this variable has the value
6407 newly created local folders will be in Maildir format.
6411 Checks for new mail in the current folder each time the prompt is shown.
6412 A Maildir folder must be re-scanned to determine if new mail has arrived.
6413 If this variable is set to the special value
6415 then a Maildir folder will not be rescanned completely, but only
6416 timestamp changes are detected.
6420 .It Va on-compose-enter , on-compose-leave
6421 \*(ID Macro hooks which will be executed before compose mode is
6422 entered, and after composing has been finished, respectively.
6423 Please note that this interface is very likely to change in v15, and
6424 should therefore possibly even be seen as experimental.
6426 are by default enabled for these hooks, causing any setting to be
6427 forgotten after the message has been sent.
6428 The following variables will be set temporarily during execution of the
6431 .Bl -tag -compact -width ".It Va compose_subject"
6434 .It Va compose-sender
6436 .It Va compose-to , compose-cc , compose-bcc
6437 The list of receiver addresses as a space-separated list.
6438 .It Va compose-subject
6444 \*(BO Causes the filename given in the
6447 and the sender-based filenames for the
6451 commands to be interpreted relative to the directory given in the
6453 variable rather than to the current directory,
6454 unless it is set to an absolute pathname.
6458 \*(BO If set, each message feed through the command given for
6460 is followed by a formfeed character
6464 .It Va password-USER@HOST , password-HOST , password
6465 \*(IN Variable chain that sets a password, which is used in case none has
6466 been given in the protocol and account-specific URL;
6467 as a last resort \*(UA will ask for a password on the user's terminal if
6468 the authentication method requires a password.
6469 Specifying passwords in a startup file is generally a security risk;
6470 the file should be readable by the invoking user only.
6472 .It Va password-USER@HOST
6473 \*(OU (see the chain above for \*(IN)
6474 Set the password for
6478 If no such variable is defined for a host,
6479 the user will be asked for a password on standard input.
6480 Specifying passwords in a startup file is generally a security risk;
6481 the file should be readable by the invoking user only.
6485 \*(BO Send messages to the
6487 command without performing MIME and character set conversions.
6491 .It Va pipe-TYPE/SUBTYPE
6492 When a MIME message part of type
6494 (case-insensitive) is displayed or quoted,
6495 its text is filtered through the value of this variable interpreted as
6499 forces interpretation of the message part as plain text, e.g.,
6500 .Ql set pipe-application/xml=@
6501 will henceforth display XML
6503 (The same could also be achieved by adding a MIME type marker with the
6506 And \*(OPally MIME type handlers may be defined via
6507 .Sx "The Mailcap files"
6508 \(em corresponding flag strings are shown in parenthesis below.)
6513 can in fact be used to adjust usage and behaviour of a following shell
6514 command specification by appending trigger characters to it, e.g., the
6515 following hypothetical command specification could be used:
6516 .Bd -literal -offset indent
6517 set pipe-X/Y="@*!++=@vim ${NAIL_FILENAME_TEMPORARY}"
6521 .Bl -tag -compact -width ".It Ql __"
6523 Simply by using the special
6525 prefix the MIME type (shell command) handler will only be invoked to
6526 display or convert the MIME part if the message is addressed directly
6527 and alone by itself.
6528 Use this trigger to disable this and always invoke the handler
6529 .Pf ( Cd x-mailx-always ) .
6532 If set the handler will not be invoked when a message is to be quoted,
6533 but only when it will be displayed
6534 .Pf ( Cd x-mailx-noquote ) .
6537 The command will be run asynchronously, i.e., without blocking \*(UA,
6538 which may be a handy way to display a, e.g., PDF file while also
6539 continuing to read the mail message
6540 .Pf ( Cd x-mailx-async ) .
6541 Asynchronous execution implies
6545 The command must be run on an interactive terminal, \*(UA will
6546 temporarily release the terminal to it
6547 .Pf ( Cd needsterminal ) .
6548 This flag is mutual exclusive with
6550 will only be used in interactive mode and implies
6554 Request creation of a zero-sized temporary file, the absolute pathname
6555 of which will be made accessable via the environment variable
6556 .Ev NAIL_FILENAME_TEMPORARY
6557 .Pf ( Cd x-mailx-tmpfile ) .
6558 If this trigger is given twice then the file will be unlinked
6559 automatically by \*(UA when the command loop is entered again at latest
6560 .Pf ( Cd x-mailx-tmpfile-unlink ) .
6561 (Don't use this for asynchronous handlers.)
6564 Normally the MIME part content is passed to the handler via standard
6565 input; if this flag is set then the data will instead be written into
6566 .Ev NAIL_FILENAME_TEMPORARY
6567 .Pf ( Cd x-mailx-tmpfile-fill ) ,
6568 the creation of which is implied; note however that in order to cause
6569 deletion of the temporary file you still have to use two plus signs
6574 To avoid ambiguities with normal shell command content you can use
6575 another at-sign to forcefully terminate interpretation of remaining
6577 (Any character not in this list will have the same effect.)
6581 Some information about the MIME part to be displayed is embedded into
6582 the environment of the shell command:
6585 .Bl -tag -compact -width ".It Ev _AIL__ILENAME__ENERATED"
6588 The MIME content-type of the part, if known, the empty string otherwise.
6591 .It Ev NAIL_CONTENT_EVIDENCE
6593 .Va mime-counter-evidence
6594 includes the carry-around-bit (2), then this will be set to the detected
6595 MIME content-type; not only then identical to
6596 .Ev \&\&NAIL_CONTENT
6600 .It Ev NAIL_FILENAME
6601 The filename, if any is set, the empty string otherwise.
6604 .It Ev NAIL_FILENAME_GENERATED
6608 .It Ev NAIL_FILENAME_TEMPORARY
6609 If temporary file creation has been requested through the command prefix
6610 this variable will be set and contain the absolute pathname of the
6615 The temporary directory that \*(UA uses.
6616 Usually identical to
6618 but guaranteed to be set and usable by child processes;
6619 to ensure the latter condition for
6626 .It Va pipe-EXTENSION
6627 This is identical to
6628 .Va pipe-TYPE/SUBTYPE
6631 (normalized to lowercase using character mappings of the ASCII charset)
6632 names a file extension, e.g.,
6634 Handlers registered using this method take precedence.
6637 .It Va pop3-auth-USER@HOST , pop3-auth-HOST , pop3-auth
6638 \*(OP\*(IN Variable chain that sets the POP3 authentication method.
6639 The only possible value as of now is
6641 which is thus the default.
6644 .Mx Va pop3-bulk-load
6645 .It Va pop3-bulk-load-USER@HOST , pop3-bulk-load-HOST , pop3-bulk-load
6646 \*(BO\*(OP When accessing a POP3 server \*(UA loads the headers of
6647 the messages, and only requests the message bodies on user request.
6648 For the POP3 protocol this means that the message headers will be
6650 If this option is set then \*(UA will download only complete messages
6651 from the given POP3 server(s) instead.
6653 .Mx Va pop3-keepalive
6654 .It Va pop3-keepalive-USER@HOST , pop3-keepalive-HOST , pop3-keepalive
6655 \*(OP POP3 servers close the connection after a period of inactivity;
6656 the standard requires this to be at least 10 minutes,
6657 but practical experience may vary.
6658 Setting this variable to a numeric value greater than
6662 command to be sent each value seconds if no other operation is performed.
6665 .It Va pop3-no-apop-USER@HOST , pop3-no-apop-HOST , pop3-no-apop
6666 \*(BO\*(OP Unless this variable is set the
6668 authentication method will be used when connecting to a POP3 server that
6672 is that the password is not sent in clear text over the wire and that
6673 only a single packet is sent for the user/password tuple.
6675 .Va pop3-no-apop-HOST
6678 .Mx Va pop3-use-starttls
6679 .It Va pop3-use-starttls-USER@HOST , pop3-use-starttls-HOST , pop3-use-starttls
6680 \*(BO\*(OP Causes \*(UA to issue a
6682 command to make an unencrypted POP3 session SSL/TLS encrypted.
6683 This functionality is not supported by all servers,
6684 and is not used if the session is already encrypted by the POP3S method.
6686 .Va pop3-use-starttls-HOST
6690 .It Va print-alternatives
6691 \*(BO When a MIME message part of type
6692 .Ql multipart/alternative
6693 is displayed and it contains a subpart of type
6695 other parts are normally discarded.
6696 Setting this variable causes all subparts to be displayed,
6697 just as if the surrounding part was of type
6698 .Ql multipart/mixed .
6702 The string shown when a command is accepted.
6703 Prompting may be prevented by either setting this to the null string
6706 The same XSI escape sequences that are understood by the
6708 command may be used within
6711 In addition, the following \*(UA specific additional sequences are
6718 is set, in which case it expands to
6722 is the default value of
6725 which will expand to
6727 if the last command failed and to
6731 which will expand to the name of the currently active
6733 if any, and to the empty string otherwise, and
6735 which will expand to the name of the currently active mailbox.
6736 (Note that the prompt buffer is size-limited, excess is cut off.)
6742 to encapsulate the expansions of the
6746 escape sequences as necessary to correctly display bidirectional text,
6747 this is not true for the final string that makes up
6749 as such, i.e., real BIDI handling is not supported.
6751 When a newer version of the
6753 .Sx "Command line editor"
6754 is used, any escape sequence must itself be encapsulated with another
6755 escape character for usage with the
6757 mechanism: \*(UA configures the control character
6763 \*(BO Suppresses the printing of the version when first invoked.
6767 If set, \*(UA starts a replying message with the original message
6768 prefixed by the value of the variable
6770 Normally, a heading consisting of
6771 .Dq Fromheaderfield wrote:
6772 is put before the quotation.
6777 variable, this heading is omitted.
6780 is assigned, the headers selected by the
6781 .Ic ignore Ns / Ns Ic retain
6782 commands are put above the message body,
6785 acts like an automatic
6791 is assigned, all headers are put above the message body and all MIME
6792 parts are included, making
6794 act like an automatic
6797 .Va quote-as-attachment .
6800 .It Va quote-as-attachment
6801 \*(BO Add the original message in its entirety as a
6803 MIME attachment when replying to a message.
6804 Note this works regardless of the setting of
6809 \*(OP Can be set in addition to
6811 Setting this turns on a more fancy quotation algorithm in that leading
6812 quotation characters are compressed and overlong lines are folded.
6814 can be set to either one or two (space separated) numeric values,
6815 which are interpreted as the maximum (goal) and the minimum line length,
6816 respectively, in a spirit rather equal to the
6818 program, but line-, not paragraph-based.
6819 If not set explicitly the minimum will reflect the goal algorithmically.
6820 The goal can't be smaller than the length of
6822 plus some additional pad.
6823 Necessary adjustments take place silently.
6826 .It Va recipients-in-cc
6827 \*(BO On group replies, specify only the sender of the original mail in
6829 and mention the other recipients in the secondary
6831 By default all recipients of the original mail will be addressed via
6836 If defined, gives the pathname of the folder used to record all outgoing
6838 If not defined, then outgoing mail is not saved.
6839 When saving to this folder fails the message is not sent,
6840 but instead saved to
6844 .It Va record-resent
6845 \*(BO If both this variable and the
6852 commands save messages to the
6854 folder as it is normally only done for newly composed messages.
6857 .It Va reply-in-same-charset
6858 \*(BO If this variable is set \*(UA first tries to use the same
6859 character set of the original message for replies.
6860 If this fails, the mechanism described in
6861 .Sx "Character sets"
6862 is evaluated as usual.
6865 .It Va reply_strings
6866 Can be set to a comma-separated list of (case-insensitive according to
6867 ASCII rules) strings which shall be recognized in addition to the
6870 reply message indicators \(en builtin are
6872 which is mandated by RFC 5322, as well as the german
6877 A list of addresses to put into the
6879 field of the message header.
6880 Members of this list are handled as if they were in the
6885 .It Va reply-to-honour
6888 header is honoured when replying to a message via
6892 This is a quadoption; if set without a value it defaults to
6896 .It Va rfc822-body-from_
6897 \*(BO This variable can be used to force displaying a so-called
6899 line for messages that are embedded into an envelope mail via the
6901 MIME mechanism, for more visual convenience.
6905 \*(BO Enable saving of (partial) messages in
6907 upon interrupt or delivery error.
6911 When \*(UA initially displays the message headers it determines the
6912 number to display by looking at the speed of the terminal.
6913 The faster the terminal, the more will be shown.
6914 This option specifies the number to use and overrides the calculation.
6915 This number is also used for scrolling with the
6918 Overall screen dimensions and pager usage is influenced by the
6919 environment variables
6927 .It Va searchheaders
6928 \*(BO Expand message-list specifiers in the form
6930 to all messages containing the substring
6934 The string search is case insensitive.
6938 \*(OP A comma-separated list of character set names that can be used in
6939 outgoing internet mail.
6940 The value of the variable
6942 is automatically appended to this list of character-sets.
6943 If no character set conversion capabilities are compiled into \*(UA then
6944 the only supported charset is
6947 .Va sendcharsets-else-ttycharset
6948 and refer to the section
6949 .Sx "Character sets"
6950 for the complete picture of character set conversion in \*(UA.
6953 .It Va sendcharsets-else-ttycharset
6954 \*(BO\*(OP If this variable is set, but
6956 is not, then \*(UA acts as if
6958 had been set to the value of the variable
6960 In effect this combination passes through the message data in the
6961 character set of the current locale (given that
6963 hasn't been set manually), i.e., without converting it to the
6965 fallback character set.
6966 Thus, mail message text will be in ISO-8859-1 encoding when send from
6967 within a ISO-8859-1 locale, and in UTF-8 encoding when send from within
6969 If no character set conversion capabilities are available in \*(UA then
6970 the only supported character set is
6975 An address that is put into the
6977 field of outgoing messages, quoting RFC 5322: the mailbox of the agent
6978 responsible for the actual transmission of the message.
6979 This field should normally not be used unless the
6981 field contains more than one address, on which case it is required.
6984 address is handled as if it were in the
6990 To use an alternate mail transport agent (MTA),
6991 set this option to the full pathname of the program to use.
6992 It may be necessary to set
6993 .Va sendmail-progname
6996 The MTA will be passed command line arguments from several possible
6997 sources: from the variable
6998 .Va sendmail-arguments
6999 if set, from the command line if given and the variable
7002 Argument processing of the MTA will be terminated with a
7006 The otherwise occurring implicit usage of the following MTA command line
7007 arguments can be disabled by setting the boolean option
7008 .Va sendmail-no-default-arguments
7009 (which will also disable passing
7013 (for not treating a line with only a dot
7015 character as the end of input),
7023 option is set); in conjunction with the
7025 command line option \*(UA will also pass
7031 .It Va sendmail-arguments
7032 Arguments to pass through to the Mail-Transfer-Agent can be given via
7034 The content of this variable will be split up in a vector of arguments
7035 which will be joined onto other possible MTA options:
7037 .Dl set sendmail-arguments='-t -X \&"/tmp/my log\&"'
7040 .It Va sendmail-no-default-arguments
7041 \*(BO Unless this option is set \*(UA will pass some well known
7042 standard command line options to the defined
7044 program, see there for more.
7047 .It Va sendmail-progname
7048 Many systems use a so-called
7050 environment to ensure compatibility with
7052 This works by inspecting the name that was used to invoke the mail
7054 If this variable is set then the mailwrapper (the program that is
7055 actually executed when calling
7057 will treat its contents as that name.
7063 \*(BO When sending a message wait until the MTA (including the builtin
7064 SMTP one) exits before accepting further commands.
7066 with this variable set errors reported by the MTA will be recognizable!
7067 If the MTA returns a non-zero exit status,
7068 the exit status of \*(ua will also be non-zero.
7072 \*(BO Setting this option causes \*(UA to start at the last message
7073 instead of the first one when opening a mail folder.
7077 \*(BO Causes \*(UA to use the sender's real name instead of the plain
7078 address in the header field summary and in message specifications.
7082 \*(BO Causes the recipient of the message to be shown in the header
7083 summary if the message was sent by the user.
7087 A string for use with the
7093 A string for use with the
7099 Must correspond to the name of a readable file if set.
7100 The file's content is then appended to each singlepart message
7101 and to the first part of each multipart message.
7102 Be warned that there is no possibility to edit the signature for an
7106 .It Va skipemptybody
7107 \*(BO If an outgoing message does not contain any text in its first or
7108 only message part, do not send it but discard it silently (see also the
7114 \*(OP Specifies a directory with CA certificates in PEM (Privacy
7115 Enhanced Mail) format for verification of S/MIME signed messages.
7118 .It Va smime-ca-file
7119 \*(OP Specifies a file with CA certificates in PEM format for
7120 verification of S/MIME signed messages.
7123 .It Va smime-cipher-USER@HOST , smime-cipher
7124 \*(OP Specifies the cipher to use when generating S/MIME encrypted
7125 messages (for the specified account).
7126 RFC 5751 mandates a default of
7129 Possible values are (case-insensitive and) in decreasing cipher strength:
7137 (DES EDE3 CBC, 168 bits; default if
7139 isn't available) and
7143 The actually available cipher algorithms depend on the cryptographic
7144 library that \*(UA uses.
7145 \*(OP Support for more cipher algorithms may be available through
7146 dynamic loading via, e.g.,
7147 .Xr EVP_get_cipherbyname 3
7148 (OpenSSL) if \*(UA has been compiled to support this.
7151 .It Va smime-crl-dir
7152 \*(OP Specifies a directory that contains files with CRLs in PEM format
7153 to use when verifying S/MIME messages.
7156 .It Va smime-crl-file
7157 \*(OP Specifies a file that contains a CRL in PEM format to use when
7158 verifying S/MIME messages.
7161 .It Va smime-encrypt-USER@HOST
7162 \*(OP If this variable is set, messages send to the given receiver are
7163 encrypted before sending.
7164 The value of the variable must be set to the name of a file that
7165 contains a certificate in PEM format.
7167 If a message is sent to multiple recipients,
7168 each of them for whom a corresponding variable is set will receive an
7169 individually encrypted message;
7170 other recipients will continue to receive the message in plain text
7172 .Va smime-force-encryption
7174 It is recommended to sign encrypted messages, i.e., to also set the
7179 .It Va smime-force-encryption
7180 \*(BO\*(OP Causes \*(UA to refuse sending unencrypted messages.
7183 .It Va smime-no-default-ca
7184 \*(BO\*(OP Don't load default CA locations when verifying S/MIME signed
7189 \*(BO\*(OP S/MIME sign outgoing messages with the user's private key
7190 and include the user's certificate as a MIME attachment.
7191 Signing a message enables a recipient to verify that the sender used
7192 a valid certificate,
7193 that the email addresses in the certificate match those in the message
7194 header and that the message content has not been altered.
7195 It does not change the message text,
7196 and people will be able to read the message as usual.
7198 .Va smime-sign-cert , smime-sign-include-certs
7200 .Va smime-sign-message-digest .
7202 .Mx Va smime-sign-cert
7203 .It Va smime-sign-cert-USER@HOST , smime-sign-cert
7204 \*(OP Points to a file in PEM format.
7205 For the purpose of signing and decryption this file needs to contain the
7206 user's private key as well as his certificate.
7210 is always derived from the value of
7212 (or, if that contains multiple addresses,
7214 For the purpose of encryption the recipient's public encryption key
7215 (certificate) is expected; the command
7217 can be used to save certificates of signed messages (the section
7218 .Sx "Signed and encrypted messages with S/MIME"
7219 gives some details).
7220 This mode of operation is usually driven by the specialized form.
7222 When decrypting messages the account is derived from the recipient
7227 of the message, which are searched for addresses for which such
7229 \*(UA always uses the first address that matches,
7230 so if the same message is sent to more than one of the user's addresses
7231 using different encryption keys, decryption might fail.
7233 .Mx Va smime-sign-include-certs
7234 .It Va smime-sign-include-certs-USER@HOST , smime-sign-include-certs
7235 \*(OP If used, this is supposed to a consist of a comma-separated list
7236 of files, each of which containing a single certificate in PEM format to
7237 be included in the S/MIME message in addition to the
7240 This is most useful for long certificate chains if it is desired to aid
7241 the receiving party's verification process.
7242 Note that top level certificates may also be included in the chain but
7243 don't play a role for verification.
7245 .Va smime-sign-cert .
7246 Remember that for this
7248 refers to the variable
7250 (or, if that contains multiple addresses,
7253 .Mx Va smime-sign-message-digest
7254 .It Va smime-sign-message-digest-USER@HOST , smime-sign-message-digest
7255 \*(OP Specifies the message digest to use when signing S/MIME messages.
7256 RFC 5751 mandates a default of
7258 Possible values are (case-insensitive and) in decreasing cipher strength:
7266 The actually available message digest algorithms depend on the
7267 cryptographic library that \*(UA uses.
7268 \*(OP Support for more message digest algorithms may be available
7269 through dynamic loading via, e.g.,
7270 .Xr EVP_get_digestbyname 3
7271 (OpenSSL) if \*(UA has been compiled to support this.
7272 Remember that for this
7274 refers to the variable
7276 (or, if that contains multiple addresses,
7282 \*(OP Normally \*(UA invokes the program defined via
7284 to transfer messages, as described in
7285 .Sx "On sending mail, and non-interactive mode" .
7288 variable will instead cause SMTP network connections be made to the
7289 server specified therein in order to directly submit the message.
7290 \*(UA knows about three different
7291 .Dq SMTP protocols :
7293 .Bl -bullet -compact
7295 The plain SMTP protocol (RFC 5321) that normally lives on the
7296 server port 25 and requires setting the
7297 .Va smtp-use-starttls
7298 variable to enter a SSL/TLS encrypted session state.
7299 Assign a value like \*(IN
7300 .Ql [smtp://][user[:password]@]server[:port]
7302 .Ql [smtp://]server[:port] )
7303 to choose this protocol.
7305 Then the so-called SMTPS which is supposed to live on server port 465
7306 and is automatically SSL/TLS secured.
7307 Unfortunately it never became a standardized protocol and may thus not
7308 be supported by your hosts network service database
7309 \(en in fact the port number has already been reassigned to other
7312 SMTPS is nonetheless a commonly offered protocol and thus can be
7313 chosen by assigning a value like \*(IN
7314 .Ql smtps://[user[:password]@]server[:port]
7316 .Ql smtps://server[:port] ) ;
7317 due to the mentioned problems it is usually necessary to explicitly
7322 Finally there is the SUBMISSION protocol (RFC 6409), which usually
7323 lives on server port 587 and is practically identically to the SMTP
7324 protocol from \*(UA's point of view beside that; it requires setting the
7325 .Va smtp-use-starttls
7326 variable to enter a SSL/TLS secured session state.
7327 Assign a value like \*(IN
7328 .Ql submission://[user[:password]@]server[:port]
7330 .Ql submission://server[:port] ) .
7333 For more on credentials etc. please see
7334 .Sx "On URL syntax and credential lookup" .
7335 The SMTP transfer is executed in a child process, which runs
7336 asynchronously unless either the
7341 If it receives a TERM signal, it will abort and save the message to
7346 .It Va smtp-auth-USER@HOST , smtp-auth-HOST , smtp-auth
7347 \*(OP Variable chain that sets the SMTP authentication method.
7354 as well as the \*(OPal methods
7360 method doesn't need any user credentials,
7362 requires a user name and all other methods require a user name and
7370 .Va smtp-auth-password
7372 .Va smtp-auth-user ) .
7377 .Va smtp-auth-USER@HOST :
7378 may override dependend on sender address in the variable
7381 .It Va smtp-auth-password
7382 \*(OP\*(OU Sets the global fallback password for SMTP authentication.
7383 If the authentication method requires a password, but neither
7384 .Va smtp-auth-password
7386 .Va smtp-auth-password-USER@HOST
7388 \*(UA will ask for a password on the user's terminal.
7390 .It Va smtp-auth-password-USER@HOST
7392 .Va smtp-auth-password
7393 for specific values of sender addresses, dependent upon the variable
7396 .It Va smtp-auth-user
7397 \*(OP\*(OU Sets the global fallback user name for SMTP authentication.
7398 If the authentication method requires a user name, but neither
7401 .Va smtp-auth-user-USER@HOST
7403 \*(UA will ask for a user name on the user's terminal.
7405 .It Va smtp-auth-user-USER@HOST
7408 for specific values of sender addresses, dependent upon the variable
7412 .It Va smtp-hostname
7413 \*(IN Normally \*(UA uses the variable
7415 to derive the necessary
7417 information to issue a
7422 can be used to use the
7424 from the SMTP account
7431 from the content of this variable (or, if that is the empty string,
7433 or the local hostname as a last resort).
7434 This often allows using an address that is itself valid but hosted by
7435 a provider other than which (in
7437 is about to send the message.
7438 Setting this variable also influences the generated
7441 .Mx Va smtp-use-starttls
7442 .It Va smtp-use-starttls-USER@HOST , smtp-use-starttls-HOST , smtp-use-starttls
7443 \*(BO\*(OP Causes \*(UA to issue a
7445 command to make an SMTP session SSL/TLS encrypted, i.e., to enable
7446 transport layer security.
7450 .It Va spam-interface
7451 \*(OP In order to use any of the spam-related commands (like, e.g.,
7453 the desired spam interface must be defined by setting this variable.
7454 Please refer to the manual section
7456 for the complete picture of spam handling in \*(UA.
7457 All or none of the following interfaces may be available:
7459 .Bl -tag -width ".It Ql _ilte_"
7465 .Pf ( Lk http://spamassassin.apache.org SpamAssassin )
7467 Different to the generic filter interface \*(UA will automatically add
7468 the correct arguments for a given command and has the necessary
7469 knowledge to parse the program's output.
7472 will have been compiled into the \*(UA binary if
7477 Shall it be necessary to define a specific connection type (rather than
7478 using a configuration file for that), the variable
7480 can be used as in, e.g.,
7481 .Ql -d server.example.com -p 783 .
7482 It is also possible to specify a per-user configuration via
7484 Note that this interface doesn't inspect the
7486 flag of a message for the command
7490 \*(UA will directly communicate with the
7496 stream socket as specified in
7498 It is possible to specify a per-user configuration via
7502 generic spam filter support via freely configurable hooks.
7503 This interface is ment for programs like
7507 and requires according behaviour in respect to the hooks' exit
7508 status for at least the command
7511 meaning a message is spam,
7515 for unsure and any other return value indicating a hard error);
7516 since the hooks can include shell code snippets diverting behaviour
7517 can be intercepted as necessary.
7519 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
7522 .Va spamfilter-spam ;
7525 contains examples for some programs.
7526 The process environment of the hooks will have the variables
7527 .Ev NAIL_TMPDIR , TMPDIR
7529 .Ev NAIL_FILENAME_GENERATED
7531 Note that spam score support for
7533 isn't supported unless the \*(OPtional regular expression support is
7535 .Va spamfilter-rate-scanscore
7542 \*(OP Messages that exceed this size won't be passed through to the
7544 .Va spam-interface .
7545 The default is 420000 bytes.
7548 .It Va spamc-command
7549 \*(OP The path to the
7553 .Va spam-interface .
7554 Note that the path is not expanded, but used
7556 A fallback path will have been compiled into the \*(UA binary if the
7557 executable had been found during compilation.
7560 .It Va spamc-arguments
7561 \*(OP Even though \*(UA deals with most arguments for the
7564 automatically, it may at least sometimes be desirable to specifiy
7565 connection-related ones via this variable, e.g.,
7566 .Ql -d server.example.com -p 783 .
7570 \*(OP Specify a username for per-user configuration files for the
7572 .Va spam-interface .
7573 If this is set to the empty string then \*(UA will use the name of the
7579 \*(OP Specify the path of the
7581 domain socket on which
7583 listens for connections for the
7585 .Va spam-interface .
7586 Note that the path is not expanded, but used
7591 \*(OP Specify a username for per-user configuration files for the
7593 .Va spam-interface .
7594 If this is set to the empty string then \*(UA will use the name of the
7603 .It Va spamfilter-ham , spamfilter-noham , \
7604 spamfilter-nospam , spamfilter-rate , spamfilter-spam
7605 \*(OP Command and argument hooks for the
7607 .Va spam-interface .
7610 contains examples for some programs.
7613 .It Va spamfilter-rate-scanscore
7614 \*(OP Because of the generic nature of the
7617 spam scores are not supported for it by default, but if the \*(OPtional
7618 regular expression support is available then setting this variable can
7619 be used to overcome this restriction.
7620 It is interpreted as follows: first a number (digits) is parsed that
7621 must be followed by a semicolon
7623 and an extended regular expression.
7624 Then the latter is used to parse the first output line of the
7626 hook, and, in case the evaluation is successful, the group that has been
7627 specified via the number is interpreted as a floating point scan score.
7631 \*(OP Specifies a directory with CA certificates in PEM (Pricacy
7632 Enhanced Mail) for verification of of SSL/TLS server certificates.
7634 .Xr SSL_CTX_load_verify_locations 3
7635 for more information.
7639 \*(OP Specifies a file with CA certificates in PEM format for
7640 verification of SSL/TLS server certificates.
7642 .Xr SSL_CTX_load_verify_locations 3
7643 for more information.
7646 .It Va ssl-cert-USER@HOST , ssl-cert-HOST , ssl-cert
7647 \*(OP Variable chain that sets the file name for a SSL/TLS client
7648 certificate required by some servers.
7649 This is a direct interface to the
7653 function of the OpenSSL library, if available.
7655 .Mx Va ssl-cipher-list
7656 .It Va ssl-cipher-list-USER@HOST , ssl-cipher-list-HOST , ssl-cipher-list
7657 \*(OP Specifies a list of ciphers for SSL/TLS connections.
7658 This is a direct interface to the
7662 function of the OpenSSL library, if available; see
7664 for more information.
7665 By default \*(UA doesn't set a list of ciphers, which in effect will use a
7667 specific cipher (protocol standards ship with a list of acceptable
7668 ciphers), possibly cramped to what the actually used SSL/TLS library
7669 supports \(en the manual section
7670 .Sx "An example configuration"
7671 also contains a SSL/TLS use case.
7674 .It Va ssl-config-file
7675 \*(OP If this variable is set \*(UA will call
7676 .Xr CONF_modules_load_file 3
7677 to allow OpenSSL to be configured according to the host system wide
7679 If a non-empty value is given then this will be used to specify the
7680 configuration file to be used instead of the global OpenSSL default;
7681 note that in this case it is an error if the file cannot be loaded.
7682 The application name will always be passed as
7687 \*(OP Specifies a file that contains a CRL in PEM format to use when
7688 verifying SSL/TLS server certificates.
7692 \*(OP Specifies a directory that contains files with CRLs in PEM format
7693 to use when verifying SSL/TLS server certificates.
7696 .It Va ssl-key-USER@HOST , ssl-key-HOST , ssl-key
7697 \*(OP Variable chain that sets the file name for the private key of
7698 a SSL/TLS client certificate.
7699 If unset, the name of the certificate file is used.
7700 The file is expected to be in PEM format.
7701 This is a direct interface to the
7705 function of the OpenSSL library, if available.
7708 .It Va ssl-method-USER@HOST , ssl-method-HOST , ssl-method
7710 \*(OB Please use the newer and more flexible
7712 instead: if both values are set,
7714 will take precedence!
7715 Can be set to the following values, the actually used
7717 specification to which it is mapped is shown in parenthesis:
7719 .Pf ( Ql -ALL, TLSv1.2 ) ,
7721 .Pf ( Ql -ALL, TLSv1.1 ) ,
7723 .Pf ( Ql -ALL, TLSv1 )
7726 .Pf ( Ql -ALL, SSLv3 ) ;
7731 and thus includes the SSLv3 protocol.
7732 Note that SSLv2 is no longer supported at all.
7735 .It Va ssl-no-default-ca
7736 \*(BO\*(OP Don't load default CA locations to verify SSL/TLS server
7740 .It Va ssl-protocol-USER@HOST , ssl-protocol-HOST , ssl-protocol
7741 \*(OP Specify the used SSL/TLS protocol.
7742 This is a direct interface to the
7746 function of the OpenSSL library, if available;
7747 otherwise an \*(UA internal parser is used which understands the
7748 following subset of (case-insensitive) command strings:
7754 as well as the special value
7756 Multiple specifications may be given via a comma-separated list which
7757 ignores any whitespace.
7760 plus prefix will enable a protocol, a
7762 minus prefix will disable it, so that
7764 will enable only the TLSv1.2 protocol.
7766 It depends upon the used TLS/SSL library which protocols are actually
7767 supported and which protocols are used if
7769 is not set, but note that SSLv2 is no longer supported at all and
7771 Especially for older protocols explicitly securing
7773 may be worthwile, see
7774 .Sx "An example configuration" .
7778 \*(OP Gives the pathname to an entropy daemon socket, see
7780 Not all SSL/TLS libraries support this.
7783 .It Va ssl-rand-file
7784 \*(OP Gives the filename to a file with random entropy data, see
7785 .Xr RAND_load_file 3 .
7786 If this variable is not set, or set to the empty string, or if the
7787 filename expansion failed, then
7788 .Xr RAND_file_name 3
7789 will be used to create the filename if, and only if,
7791 documents that the SSL PRNG is not yet sufficiently seeded.
7792 If \*(UA successfully seeded the SSL PRNG then it'll update the file via
7793 .Xr RAND_write_file 3 .
7794 This variable is only used if
7796 is not set (or not supported by the SSL/TLS library).
7799 .It Va ssl-verify-USER@HOST , ssl-verify-HOST , ssl-verify
7800 \*(OP Variable chain that sets the action to be performed if an error
7801 occurs during SSL/TLS server certificate validation.
7802 Valid (case-insensitive) values are
7804 (fail and close connection immediately),
7806 (ask whether to continue on standard input),
7808 (show a warning and continue),
7810 (do not perform validation).
7816 If only set without an assigned value, then this option inhibits the
7821 header fields that include obvious references to \*(UA.
7822 There are two pitfalls associated with this:
7823 First, the message id of outgoing messages is not known anymore.
7824 Second, an expert may still use the remaining information in the header
7825 to track down the originating mail user agent.
7830 suppression doesn't occur.
7834 \*(BY\*(OP If terminal capability queries
7835 .Pf ( Xr termcap 5 ,
7837 are supported and this option is set then \*(UA will try to
7839 .Dq alternate screen
7840 when in interactive mode if the
7842 inal allows to do so, so that the terminal will go back to the
7843 normal screen, leaving all the text there intact, when \*(UA exits.
7846 even when supported for this to produce appealing results the used
7848 and possibly configured
7849 .Va pipe-TYPE/SUBTYPE
7850 applications that take control over the terminal need to have
7851 corresponding support and must be configured accordingly, too, e.g., the
7853 pager should be driven with the
7859 If defined, gives the number of lines of a message to be displayed
7862 normally, the first five lines are printed.
7866 The character set of the terminal \*(UA operates on,
7867 and the one and only supported character set that \*(UA can use if no
7868 character set conversion capabilities have been compiled into it,
7869 in which case it defaults to ISO-8859-1 unless it can deduce a value
7873 Refer to the section
7874 .Sx "Character sets"
7875 for the complete picture about character sets.
7878 .It Va user-HOST , user
7879 \*(IN Variable chain that sets a global fallback user name, which is
7880 used in case none has been given in the protocol and account-specific
7882 This variable defaults to the value of the first of
7886 that is set (the former being SystemV and POSIX standard, the latter BSD).
7890 \*(BO Setting this option enables upward compatibility with \*(UA
7891 version 15.0 in respect to which configuration options are available and
7892 how they are handled.
7893 This manual uses \*(IN and \*(OU to refer to the new and the old way of
7894 doing things, respectively.
7898 \*(BO Setting this option, also controllable via the command line option
7900 causes \*(UA to be more verbose, e.g., it will display obsoletion
7901 warnings and SSL/TLS certificate chains.
7902 Even though marked \*(BO this option may be set twice in order to
7903 increase the level of verbosity even more, in which case even details of
7904 the actual message delivery and protocol conversations are shown.
7907 is sufficient to disable verbosity as such.
7913 .It Va version , version-major , version-minor , version-update
7914 \*(RO \*(UA version information: the first variable contains a string
7915 containing the complete version identification \(en this is identical to
7916 the output of the command
7918 The latter three contain only digits: the major, minor and update
7922 .It Va writebackedited
7923 If this variable is set messages modified using the
7927 commands are written back to the current folder when it is quit;
7928 it is only honoured for writable folders in MBOX format, though.
7929 Note that the editor will be pointed to the raw message content in that
7930 case, i.e., neither MIME decoding nor decryption will have been
7931 performed, and proper RFC 4155
7933 quoting of newly added or edited content is also left as an excercise to
7937 .\" }}} (INTERNAL VARIABLES)
7940 .\" .Sh ENVIRONMENT {{{
7944 .Dq environment variable
7945 should be considered an indication that the following variables are
7946 either standardized as being vivid parts of process environments, or
7947 are commonly found in there.
7948 The process environment is inherited from the
7950 once \*(UA is started, and unless otherwise explicitly noted variables
7951 in there integrate into the normal handling of
7952 .Sx "INTERNAL VARIABLES" ,
7953 from \*(UAs point of view, i.e., they can be
7955 as such in resource files and need not necessarily come from the process
7956 environment and be managed via
7960 E.g., the following example, applicable to a POSIX shell, sets the
7962 environment variable for \*(UA only, and beforehand exports the
7964 in order to affect any further processing in the running shell:
7966 .Bd -literal -offset indent
7967 $ EDITOR="vim -u ${HOME}/.vimrc"
7969 $ COLUMNS=80 \*(ua -R
7972 .Bl -tag -width ".It Ev _AILR_"
7975 The user's preferred width in column positions for the terminal screen
7977 Queried and used once on program startup.
7981 The name of the file to use for saving aborted messages if
7983 is set; this defaults to
7991 Pathname of the text editor to use in the
7995 .Sx "TILDE ESCAPES" .
7996 A default editor is used if this value is not defined.
8000 The user's home directory.
8001 This variable is only used when it resides in the process environment.
8004 to update the value at runtime.
8011 .It Ev LANG , LC_ALL , LC_COLLATE , LC_CTYPE , LC_MESSAGES
8015 .Sx "Character sets" .
8019 The user's preferred number of lines on a page or the vertical screen
8020 or window size in lines.
8021 Queried and used once on program startup.
8025 Pathname of the directory lister to use in the
8027 command when operating on local mailboxes.
8030 (path search through
8035 Force identification as the given user, i.e., identical to the
8037 command line option.
8038 This variable is standardized and therefore used in preference to the
8041 it is only used when it resides in the process environment.
8042 \*(ID The variable can be updated at runtime via
8044 but without having an effect on \*(UA itself.
8048 Is used as the user's mailbox, if set.
8049 Otherwise, a system-dependent default is used.
8050 Supports a logical subset of the special conventions that are documented
8059 \*(OP Overrides the default path search for
8060 .Sx "The Mailcap files" ,
8061 which is defined in the standard RFC 1524 as
8062 .Ql ~/.mailcap:\:/etc/mailcap:\:/usr/etc/mailcap:\:/usr/local/etc/mailcap .
8063 .\" TODO we should have a mailcaps-default virtual RDONLY option!
8064 (\*(UA makes it a configuration option, however.)
8065 Note this is not a search path, but a path search.
8069 Is used as a startup file instead of
8072 When \*(UA scripts are invoked on behalf of other users,
8073 either this variable should be set to
8077 command line option should be used in order to avoid side-effects from
8078 reading their configuration files.
8079 This variable is only used when it resides in the process environment.
8083 The name of the user's mbox file.
8084 A logical subset of the special conventions that are documented for the
8089 The fallback default is
8094 Traditionally this secondary mailbox is used as the file to save
8095 messages from the system mailbox that have been read.
8097 .Sx "Message states" .
8100 .It Ev NAIL_NO_SYSTEM_RC
8101 If this variable is set then reading of
8103 at startup is inhibited, i.e., the same effect is achieved as if \*(UA
8104 had been started up with the option
8106 This variable is only used when it resides in the process environment.
8110 \*(IN\*(OP This variable overrides the default location of the user's
8116 Pathname of the program to use in the more command or when the
8119 The default paginator is
8121 (path search through
8126 A list of directories that is searched by the shell when looking for
8127 commands (as such only recognized in the process environment).
8131 The shell to use for the commands
8137 and when starting subprocesses.
8138 A default shell is used if this option is not defined.
8142 \*(OP The terminal type for which output is to be prepared.
8143 For extended colour and font control please refer to
8144 .Sx "Coloured display" ,
8145 and for terminal capability queries to
8150 Used as directory for temporary files instead of
8153 This variable is only used when it resides in the process environment.
8156 to update the value at runtime.
8160 This variable comes from the BSD world and is only used if the POSIX
8161 standard environment variable
8163 which originates in SysV
8166 Force identification as the given user, i.e., identical to the
8168 command line option.
8169 This variable is only used when it resides in the process environment.
8170 \*(ID The variable can be updated at runtime via
8172 but without having an effect on \*(UA itself.
8176 Pathname of the text editor to use in the
8180 .Sx "TILDE ESCAPES" .
8188 .Bl -tag -width ".It Pa _etc/mime.type_"
8190 File giving initial commands.
8193 System wide initialization file.
8197 \*(OP Personal MIME type handler definition file, see
8198 .Sx "The Mailcap files" .
8199 (RFC 1524 location, the actual path is a configuration option.)
8203 \*(OP System wide MIME type handler definition file, see
8204 .Sx "The Mailcap files" .
8205 (RFC 1524 location, the actual path is a configuration option.)
8208 .It Pa ~/.mime.types
8209 Personal MIME types, see
8210 .Sx "The mime.types files" .
8213 .It Pa /etc/mime.types
8214 System wide MIME types, see
8215 .Sx "The mime.types files" .
8219 \*(IN\*(OP The default location of the users
8221 file \(en the section
8222 .Sx "The .netrc file"
8223 documents the file format.
8226 .\" .Ss "The mime.types files" {{{
8227 .Ss "The mime.types files"
8229 When sending messages \*(UA tries to determine the content type of all
8231 When displaying message content or attachments \*(UA uses the content
8232 type to decide wether it can directly display data or wether it needs to
8233 deal with content handlers.
8234 It learns about MIME types and how to treat them by reading
8236 files, the loading of which can be controlled by setting the variable
8237 .Va mimetypes-load-control .
8240 can also be used to deal with MIME types.)
8242 files have the following syntax:
8245 .Dl type/subtype extension [extension ...]
8250 are strings describing the file contents, and one or multiple
8252 s, separated by whitespace, name the part of a filename starting after
8253 the last dot (of interest).
8254 Comments may be introduced anywhere on a line with a number sign
8256 causing the remaining line to be discarded.
8258 \*(UA also supports an extended, non-portable syntax in specially
8259 crafted files, which can be loaded via the alternative value syntax of
8260 .Va mimetypes-load-control
8261 and prepends an optional
8265 .Dl [type-marker ]type/subtype extension [extension ...]
8268 The following type markers are supported:
8271 .Bl -tag -compact -offset indent -width ".It Ar _n_u"
8273 Treat message parts with this content as plain text.
8278 Treat message parts with this content as HTML tagsoup.
8279 If the \*(OPal HTML-tagsoup-to-text converter is not available treat
8280 the content as plain text instead.
8284 but instead of falling back to plain text require an explicit content
8285 handler to be defined.
8290 for sending messages:
8292 .Va mime-allow-text-controls ,
8293 .Va mimetypes-load-control .
8294 For reading etc. messages:
8295 .Sx "HTML mail and MIME attachments" ,
8296 .Sx "The Mailcap files" ,
8298 .Va mime-counter-evidence ,
8299 .Va mimetypes-load-control ,
8300 .Va pipe-TYPE/SUBTYPE ,
8301 .Va pipe-EXTENSION .
8304 .\" .Ss "The Mailcap files" {{{
8305 .Ss "The Mailcap files"
8308 .Dq User Agent Configuration Mechanism
8309 which \*(UA \*(OPally supports.
8310 It defines a file format to be used to inform mail user agent programs
8311 about the locally-installed facilities for handling various data
8312 formats, i.e., about commands and how they can be used to display, edit
8313 etc. MIME part contents, as well as a default path search that includes
8314 multiple possible locations of
8318 environment variable that can be used to overwrite that (repeating here
8319 that it is not a search path, but instead a path search specification).
8320 Any existing files will be loaded in sequence, appending any content to
8321 the list of MIME type handler directives.
8325 files consist of a set of newline separated entries.
8326 Comment lines start with a number sign
8328 (in the first column!) and are ignored.
8329 Empty lines are also ignored.
8330 All other lines form individual entries that must adhere to the syntax
8332 To extend a single entry (not comment) its line can be continued on
8333 follow lines if newline characters are
8335 by preceding them with the backslash character
8337 The standard doesn't specify how leading whitespace of follow lines is
8338 to be treated, therefore \*(UA retains it.
8342 entries consist of a number of semicolon
8344 separated fields, and the backslash
8346 character can be used to escape any following character including
8347 semicolon and itself.
8348 The first two fields are mandatory and must occur in the specified
8349 order, the remaining fields are optional and may appear in any order.
8350 Leading and trailing whitespace of content is ignored (removed).
8353 The first field defines the MIME
8355 the entry is about to handle (case-insensitively, and no backslash
8356 escaping is possible in this field).
8357 If the subtype is specified as an asterisk
8359 the entry is ment to match all subtypes of the named type, e.g.,
8361 would match any audio type.
8362 The second field defines the shell command which shall be used to
8364 MIME parts of the given type; it is implicitly called the
8371 shell commands message (MIME part) data is passed via standard input
8372 unless the given shell command includes one or more instances of the
8375 in which case these instances will be replaced with a temporary filename
8376 and the data will have been stored in the file that is being pointed to.
8379 shell commands data is assumed to be generated on standard output unless
8380 the given command includes (one ore multiple)
8382 In any case any given
8384 format is replaced with a(n already) properly quoted filename.
8385 Note that when a command makes use of a temporary file via
8387 then \*(UA will remove it again, as if the
8388 .Cd x-mailx-tmpfile ,
8389 .Cd x-mailx-tmpfile-fill
8391 .Cd x-mailx-tmpfile-unlink
8392 flags had been set; see below for more.
8395 The optional fields either define a shell command or an attribute (flag)
8396 value, the latter being a single word and the former being a keyword
8397 naming the field followed by an equals sign
8399 succeeded by a shell command, and as usual for any
8401 content any whitespace surrounding the equals sign will be removed, too.
8402 Optional fields include the following:
8405 .Bl -tag -width textualnewlines
8407 A program that can be used to compose a new body or body part in the
8414 field, but is to be used when the composing program needs to specify the
8416 header field to be applied to the composed data.
8420 A program that can be used to edit a body or body part in the given
8425 A program that can be used to print a message or body part in the given
8430 Specifies a program to be run to test some condition, e.g., the machine
8431 architecture, or the window system in use, to determine whether or not
8432 this mailcap entry applies.
8433 If the test fails, a subsequent mailcap entry should be sought; also see
8434 .Cd x-mailx-test-once .
8436 .It Cd needsterminal
8437 This flag field indicates that the given shell command must be run on
8438 an interactive terminal.
8439 \*(UA will temporarily release the terminal to the given command in
8440 interactive mode, in non-interactive mode this entry will be entirely
8441 ignored; this flag implies
8442 .Cd x-mailx-noquote .
8444 .It Cd copiousoutput
8445 A flag field which indicates that the output of the
8447 command will be an extended stream of textual output that can be
8448 (re)integrated into \*(UA's normal visual display.
8449 It is mutually exclusive with
8452 .Cd x-mailx-always .
8454 .It Cd textualnewlines
8455 A flag field which indicates that this type of data is line-oriented and
8458 all newlines should be converted to canonical form (CRLF) before
8459 encoding, and will be in that form after decoding.
8463 This field gives a file name format, in which
8465 will be replaced by a random string, the joined combination of which
8466 will be used as the filename denoted by
8467 .Ev NAIL_FILENAME_TEMPORARY .
8468 One could specify that a GIF file being passed to an image viewer should
8469 have a name ending in
8472 .Ql nametemplate=%s.gif .
8473 Note that \*(UA ignores the name template unless that solely specifies
8474 a filename suffix that consists of (ASCII) alphabetic and numeric
8475 characters, the underscore and dot only.
8478 Names a file, in X11 bitmap (xbm) format, which points to an appropriate
8479 icon to be used to visually denote the presence of this kind of data.
8480 This field is not used by \*(UA.
8483 A textual description that describes this type of data.
8485 .It Cd x-mailx-always
8486 Extension flag field that denotes that the given
8488 command shall be executed even if multiple messages will be displayed
8490 Normally messages which require external viewers that produce output
8491 which doesn't integrate into \*(UA's visual display (i.e., don't have
8493 set) have to be addressed directly and individually.
8494 (To avoid cases where, e.g., a thousand PDF viewer instances are spawned
8497 .It Cd x-mailx-even-if-not-interactive
8498 An extension flag test field \(em by default handlers without
8500 are entirely ignored in non-interactive mode, but if this flag is set
8501 then their use will be considered.
8502 It is an error if this flag is set for commands that use the flag
8505 .It Cd x-mailx-noquote
8506 An extension flag field that indicates that even a
8509 command shall not be used to generate message quotes
8510 (as it would be by default).
8512 .It Cd x-mailx-async
8513 Extension flag field that denotes that the given
8515 command shall be executed asynchronously, without blocking \*(UA.
8516 Cannot be used in conjunction with
8519 .It Cd x-mailx-test-once
8520 Extension flag which denotes wether the given
8522 command shall be evaluated once only and the (boolean) result be cached.
8523 This is handy if some global unchanging condition is to be queried, like
8524 .Dq running under the X Window System .
8526 .It Cd x-mailx-tmpfile
8527 Extension flag field that requests creation of a zero-sized temporary
8528 file, the name of which is to be placed in the environment variable
8529 .Ev NAIL_FILENAME_TEMPORARY .
8530 It is an error to use this flag with commands that include a
8534 .It Cd x-mailx-tmpfile-fill
8535 Normally the MIME part content is passed to the handler via standard
8536 input; if this flag is set then the data will instead be written into
8538 .Cd x-mailx-tmpfile .
8539 In order to cause deletion of the temporary file you will have to set
8540 .Cd x-mailx-tmpfile-unlink
8542 It is an error to use this flag with commands that include a
8546 .It Cd x-mailx-tmpfile-unlink
8547 Extension flag field that requests that the temporary file shall be
8548 deleted automatically when the command loop is entered again at latest.
8549 (Don't use this for asynchronous handlers.)
8550 It is an error to use this flag with commands that include a
8552 format, or without also setting
8555 .Cd x-mailx-tmpfile-fill .
8557 .It Cd x-mailx-tmpfile-keep
8560 implies the three tmpfile related flags above, but if you want, e.g.,
8562 and deal with the temporary file yourself, you can add in this flag to
8564 .Cd x-mailx-tmpfile-unlink .
8569 The standard includes the possibility to define any number of additional
8570 entry fields, prefixed by
8572 Flag fields apply to the entire
8574 entry \(em in some unusual cases, this may not be desirable, but
8575 differentiation can be accomplished via separate entries, taking
8576 advantage of the fact that subsequent entries are searched if an earlier
8577 one does not provide enough information.
8580 command needs to specify the
8584 command shall not, the following will help out the latter (with enabled
8588 level \*(UA will show informations about handler evaluation):
8590 .Bd -literal -offset indent
8591 application/postscript; ps-to-terminal %s; needsterminal
8592 application/postscript; ps-to-terminal %s; compose=idraw %s
8596 In fields any occurrence of the format string
8598 will be replaced by the
8601 Named parameters from the
8603 field may be placed in the command execution line using
8605 followed by the parameter name and a closing
8608 The entire parameter should appear as a single command line argument,
8609 regardless of embedded spaces; thus:
8611 .Bd -literal -offset indent
8613 Content-type: multipart/mixed; boundary=42
8616 multipart/*; /usr/local/bin/showmulti \e
8617 %t %{boundary} ; composetyped = /usr/local/bin/makemulti
8619 # Executed shell command
8620 /usr/local/bin/showmulti multipart/mixed 42
8624 .\" TODO v15: Mailcap: %n,%F
8625 Note that \*(UA doesn't support handlers for multipart MIME parts as
8626 shown in this example (as of today).
8627 \*(UA doesn't support the additional formats
8631 An example file, also showing how to properly deal with the expansion of
8633 which includes any quotes that are necessary to make it a valid shell
8634 argument by itself and thus will cause undesired behaviour when placed
8635 in additional user-provided quotes:
8637 .Bd -literal -offset indent
8639 text/richtext; richtext %s; copiousoutput
8641 text/x-perl; perl -cWT %s
8645 trap "rm -f ${infile}" EXIT\e; \e
8646 trap "exit 75" INT QUIT TERM\e; \e
8648 x-mailx-async; x-mailx-tmpfile-keep
8650 application/*; echo "This is \e"%t\e" but \e
8651 is 50 \e% Greek to me" \e; < %s head -c 1024 | cat -vET; \e
8652 copiousoutput; x-mailx-noquote
8657 .Sx "HTML mail and MIME attachments" ,
8658 .Sx "The mime.types files" ,
8661 .Va mime-counter-evidence ,
8662 .Va pipe-TYPE/SUBTYPE ,
8663 .Va pipe-EXTENSION .
8666 .\" .Ss "The .netrc file" {{{
8667 .Ss "The .netrc file"
8671 file contains user credentials for machine accounts.
8672 The default location in the user's
8674 directory may be overridden by the
8676 environment variable.
8677 The file consists of space, tabulator or newline separated tokens.
8678 \*(UA implements a parser that supports a superset of the original BSD
8679 syntax, but users should nonetheless be aware of portability glitches
8680 of that file format, shall their
8682 be usable across multiple programs and platforms:
8685 .Bl -bullet -compact
8687 BSD doesn't support single, but only double quotation marks, e.g.,
8688 .Ql password="pass with spaces" .
8690 BSD (only?) supports escaping of single characters via a backslash
8691 (e.g., a space can be escaped via
8693 in- as well as outside of a quoted string.
8695 BSD doesn't require the final quotation mark of the final user input token.
8697 At least Hewlett-Packard seems to support a format which also allows
8698 tokens to be separated with commas \(en this format is not supported!
8700 Whereas other programs may require that the
8702 file is accessible by only the user if it contains a
8708 \*(UA will always require these strict permissions.
8712 Of the following list of supported tokens \*(UA only uses (and caches)
8717 At runtime the command
8719 can be used to control \*(UAs
8723 .Bl -tag -width password
8724 .It Cd machine Ar name
8725 The hostname of the entries' machine, lowercase-normalized by \*(UA
8727 Any further file content, until either end-of-file or the occurrence
8732 first-class token is bound (only related) to the machine
8735 As an extension that shouldn't be the cause of any worries
8736 \*(UA supports a single wildcard prefix for
8738 .Bd -literal -offset indent
8739 machine *.example.com login USER password PASS
8740 machine pop3.example.com login USER password PASS
8741 machine smtp.example.com login USER password PASS
8747 .Ql pop3.example.com ,
8751 .Ql local.smtp.example.com .
8752 Note that in the example neither
8753 .Ql pop3.example.com
8755 .Ql smtp.example.com
8756 will be matched by the wildcard, since the exact matches take
8757 precedence (it is however faster to specify it the other way around).
8762 except that it is a fallback entry that is used shall none of the
8763 specified machines match; only one default token may be specified,
8764 and it must be the last first-class token.
8766 .It Cd login Ar name
8767 The user name on the remote machine.
8769 .It Cd password Ar string
8770 The user's password on the remote machine.
8772 .It Cd account Ar string
8773 Supply an additional account password.
8774 This is merely for FTP purposes.
8776 .It Cd macdef Ar name
8778 A macro is defined with the specified
8780 it is formed from all lines beginning with the next line and continuing
8781 until a blank line is (consecutive newline characters are) encountered.
8784 entries cannot be utilized by multiple machines, too, but must be
8785 defined following the
8787 they are intended to be used with.)
8790 exists, it is automatically run as the last step of the login process.
8791 This is merely for FTP purposes.
8798 .\" .Sh EXAMPLES {{{
8801 .\" .Ss "An example configuration" {{{
8802 .Ss "An example configuration"
8804 .Bd -literal -offset indent
8805 # This example assumes v15.0 compatibility mode
8808 # Where are the up-to-date SSL certificates?
8809 #set ssl-ca-dir=/etc/ssl/certs
8810 set ssl-ca-file=/etc/ssl/certs/ca-certificates.crt
8812 # (Since we manage up-to-date ones explicitly, don't use any,
8813 # possibly outdated, default certificates shipped with OpenSSL
8814 set ssl-no-default-ca
8816 # Don't use protocols older than TLS v1.2.
8817 # Change this only when the remote server doesn't support it:
8818 # maybe use ssl-protocol-HOST (or -USER@HOST) syntax to define
8819 # such explicit exceptions, then
8820 set ssl-protocol="-ALL,+TLSv1.2"
8822 # Explicitly define the list of ciphers, which may improve security,
8823 # especially with protocols older than TLS v1.2. See ciphers(1).
8824 # Hint: it is important to include "@STRENGTH": only with it the
8825 # final list will be sorted by algorithm strength.
8826 # This is an example: in reality it is possibly best to only use
8827 # ssl-cipher-list-HOST (or -USER@HOST), as necessary, again..
8828 set ssl-cipher-list="ALL:!aNULL:!MEDIUM:!LOW:\e
8829 !MD5:!RC4:!EXPORT:@STRENGTH"
8831 # Request strict transport security checks!
8832 set ssl-verify=strict
8834 # Essential setting: select allowed character sets
8835 set sendcharsets=utf-8,iso-8859-1
8837 # A very kind option: when replying to a message, first try to
8838 # use the same encoding that the original poster used herself!
8839 set reply-in-same-charset
8841 # When replying to or forwarding a message the comment and name
8842 # parts of email addresses are removed unless this variable is set
8845 # When sending messages, wait until the Mail-Transfer-Agent finishs.
8846 # Only like this you'll be able to see errors reported through the
8847 # exit status of the MTA (including the builtin SMTP one)!
8850 # Only use builtin MIME types, no mime.types(5) files
8851 set mimetypes-load-control
8853 # Default directory where we act in (relative to $HOME)
8855 # A leading "+" (often) means: under *folder*
8856 # *record* is used to save copies of sent messages
8857 set MBOX=+mbox.mbox record=+sent.mbox DEAD=+dead.mbox
8859 # Make "file mymbox" and "file myrec" go to..
8860 shortcut mymbox %:+mbox.mbox myrec +sent.mbox
8862 # Not really optional, e.g., for S/MIME
8863 set from="Your Name <youremail@domain>"
8865 # It may be necessary to set hostname and/or smtp-hostname
8866 # if the "SERVER" of smtp and "domain" of from don't match.
8867 # The `urlencode' command can be used to encode USER and PASS
8868 set smtp=(smtp[s]/submission)://[USER[:PASS]@]SERVER[:PORT] \e
8869 smtp-auth=login/plain... \e
8872 # Never refuse to start into interactive mode, and more
8874 colour-pager crt= \e
8875 followup-to followup-to-honour=ask-yes \e
8876 history-file=+.\*(uahist history-size=-1 history-gabby \e
8877 mime-counter-evidence=0xE \e
8878 prompt="\e033[31m?\e?[\e$ \e@]\e& \e033[0m" \e
8879 reply-to-honour=ask-yes
8881 # When `p'rinting messages, show only these headers
8882 # (use `P'rint for all headers and `S'how for raw message)
8883 retain date from to cc subject
8885 # Some mailing lists
8886 mlist @xyz-editor.xyz$ @xyzf.xyz$
8887 mlsubscribe ^xfans@xfans.xyz$
8889 # A real life example of a very huge free mail provider
8891 set from="Your Name <youremail@domain>"
8892 # (The plain smtp:// proto is optional)
8893 set smtp=USER:PASS@smtp.gmXil.com smtp-use-starttls
8896 # Here is a pretty large one which does not allow sending mails
8897 # if there is a domain name mismatch on the SMTP protocol level,
8898 # which would bite us if the value of from does not match, e.g.,
8899 # for people who have a sXXXXeforge project and want to speak
8900 # with the mailing list under their project account (in from),
8901 # still sending the message through their normal mail provider
8903 set from="Your Name <youremail@domain>"
8904 set smtp=smtps://USER:PASS@smtp.yaXXex.ru:465 \e
8905 hostname=yaXXex.com smtp-hostname=
8908 # Create some new commands so that, e.g., `ls /tmp' will..
8919 ghost llS !ls -aFlrS
8922 # We don't support gpg(1) directly yet. But simple --clearsign'd
8923 # message parts can be dealt with as follows:
8926 set pipe-text/plain="@*#++=@\e
8927 < \e"${NAIL_FILENAME_TEMPORARY}\e" awk \e
8928 -v TMPFILE=\e"${NAIL_FILENAME_TEMPORARY}\e" '\e
8930 /^-----BEGIN PGP SIGNED MESSAGE-----/,/^$/ {\e
8933 print \e"--- GPG --verify ---\e";\e
8934 system(\e"gpg --verify \e" TMPFILE \e" 2>&1\e");\e
8935 print \e"--- GPG --verify ---\e";\e
8939 /^-----BEGIN PGP SIGNATURE-----/,\e
8940 /^-----END PGP SIGNATURE-----/ {\e
8950 !printf 'Key IDs to gpg --recv-keys: ';\e
8952 gpg --recv-keys ${keyids};
8958 When storing passwords in
8960 appropriate permissions should be set on this file with
8961 .Ql $ chmod 0600 \*(ur .
8964 is available user credentials can be stored in the central
8966 file instead; e.g., here is a different version of the example account
8967 that sets up SMTP and POP3:
8969 .Bd -literal -offset indent
8971 set from="Your Name <youremail@domain>"
8973 #set agent-shell-lookup="gpg -d .pass.gpg"
8975 set smtp=smtps://smtp.yXXXXx.ru:465 \e
8976 smtp-hostname= hostname=yXXXXx.com
8977 set pop3-keepalive=240 pop3-no-apop-pop.yXXXXx.ru
8978 ghost xp fi pop3s://pop.yXXXXx.ru
8987 .Bd -literal -offset indent
8988 machine *.yXXXXx.ru login USER password PASS
8993 .Va agent-shell-lookup
8994 is available things could be diversified further by using encrypted
8995 password storage: for this, don't specify
8999 file and instead uncomment the line that defines agent lookup in the
9002 above, then create the encrypted password storage file
9005 .Bd -literal -offset indent
9008 $ eval `gpg-agent --daemon \e
9009 --pinentry-program=/usr/bin/pinentry-curses \e
9010 --max-cache-ttl 99999 --default-cache-ttl 99999`
9014 This configuration should now work just fine (use the
9016 command line option for a(n almost) dry-run):
9019 .Dl $ echo text | \*(ua -vv -AXandeX -s Subject some@where
9022 .\" .Ss "Signed and encrypted messages with S/MIME" {{{
9023 .Ss "Signed and encrypted messages with S/MIME"
9025 \*(OP S/MIME provides two central mechanisms:
9026 message signing and message encryption.
9027 A signed message contains some data in addition to the regular text.
9028 The data can be used to verify that the message was sent using a valid
9029 certificate, that the sender's address in the message header matches
9030 that in the certificate, and that the message text has not been altered.
9031 Signing a message does not change its regular text;
9032 it can be read regardless of whether the recipient's software is able to
9036 It is thus usually possible to sign all outgoing messages if so desired.
9037 Encryption, in contrast, makes the message text invisible for all people
9038 except those who have access to the secret decryption key.
9039 To encrypt a message, the specific recipient's public encryption key
9041 It is therefore not possible to send encrypted mail to people unless their
9042 key has been retrieved from either previous communication or public key
9044 A message should always be signed before it is encrypted.
9045 Otherwise, it is still possible that the encrypted message text is
9049 A central concept to S/MIME is that of the certification authority (CA).
9050 A CA is a trusted institution that issues certificates.
9051 For each of these certificates it can be verified that it really
9052 originates from the CA, provided that the CA's own certificate is
9054 A set of CA certificates is usually delivered with OpenSSL and installed
9056 If you trust the source of your OpenSSL software installation,
9057 this offers reasonable security for S/MIME on the Internet.
9059 .Va ssl-no-default-ca
9063 .Va smime-ca-dir . )
9064 In general, a certificate cannot be more secure than the method its CA
9065 certificate has been retrieved with, though.
9066 Thus if you download a CA certificate from the Internet,
9067 you can only trust the messages you verify using that certificate as
9068 much as you trust the download process.
9071 The first thing you need for participating in S/MIME message exchange is
9072 your personal certificate, including a private key.
9073 The certificate contains public information, in particular your name and
9074 your email address(es), and the public key that is used by others to
9075 encrypt messages for you,
9076 and to verify signed messages they supposedly received from you.
9077 The certificate is included in each signed message you send.
9078 The private key must be kept secret.
9079 It is used to decrypt messages that were previously encrypted with your
9080 public key, and to sign messages.
9083 For personal use it is recommended that you get a S/MIME certificate
9084 from one of the major CAs on the Internet using your WWW browser.
9085 Many CAs offer such certificates for free.
9087 .Lk https://www.CAcert.org
9088 which issues client and server certificates to members of their
9089 community for free; their root certificate
9090 .Pf ( Lk https://\:www.cacert.org/\:certs/\:root.crt )
9091 is often not in the default set of trusted CA root certificates, though,
9092 which means you will have to download their root certificate separately
9093 and ensure it is part of our S/MIME certificate validation chain by
9096 or as a vivid member of the
9098 But let's take a step-by-step tour on how to setup S/MIME with
9099 a certificate from CAcert.org despite this situation!
9102 First of all you will have to become a member of the CAcert.org
9103 community, simply by registrating yourself via the web interface.
9104 Once you are, create and verify all email addresses you want to be able
9105 to create signed and encrypted messages for/with using the corresponding
9106 entries of the web interface.
9107 Now ready to create S/MIME certificates, so let's create a new
9108 .Dq client certificate ,
9109 ensure to include all email addresses that should be covered by the
9110 certificate in the following web form, and also to use your name as the
9114 Create a private key and a certificate request on your local computer
9115 (please see the manual pages of the used commands for more in-depth
9116 knowledge on what the used arguments etc. do):
9119 .Dl openssl req -nodes -newkey rsa:4096 -keyout key.pem -out creq.pem
9122 Afterwards copy-and-paste the content of
9124 into the certificate-request (CSR) field of the web form on the
9125 CAcert.org website (you may need to unfold some
9126 .Dq advanced options
9127 to see the corresponding text field).
9128 This last step will ensure that your private key (which never left your
9129 box) and the certificate belong together (through the public key that
9130 will find its way into the certificate via the certificate-request).
9131 You are now ready and can create your CAcert certified certificate.
9132 Download and store or copy-and-paste it as
9137 In order to use your new S/MIME setup you will have to create
9138 a combined private key/public key (certificate) file:
9141 .Dl cat key.pem pub.crt > ME@HERE.com.paired
9144 This is the file \*(UA will work with.
9145 If you have created your private key with a passphrase then \*(UA will
9146 ask you for it whenever a message is signed or decrypted.
9147 Set the following variables to henceforth use S/MIME (setting
9149 is of interest for verification only):
9151 .Bd -literal -offset indent
9152 set smime-ca-file=ALL-TRUSTED-ROOT-CERTS-HERE \e
9153 smime-sign-cert=ME@HERE.com.paired \e
9154 smime-sign-message-digest=SHA256 \e
9159 From each signed message you send, the recipient can fetch your
9160 certificate and use it to send encrypted mail back to you.
9161 Accordingly if somebody sends you a signed message, you can do the same,
9164 command to check the validity of the certificate.
9167 Variables of interest for S/MIME signing:
9171 .Va smime-crl-file ,
9172 .Va smime-no-default-ca ,
9174 .Va smime-sign-cert ,
9175 .Va smime-sign-include-certs
9177 .Va smime-sign-message-digest .
9180 After it has been verified save the certificate via
9182 and tell \*(UA that it should use it for encryption for further
9183 communication with that somebody:
9185 .Bd -literal -offset indent
9187 set smime-encrypt-USER@HOST=FILENAME \e
9188 smime-cipher-USER@HOST=AES256
9192 Additional variables of interest for S/MIME en- and decryption:
9195 .Va smime-encrypt-USER@HOST .
9198 You should carefully consider if you prefer to store encrypted messages
9200 If you do, anybody who has access to your mail folders can read them,
9201 but if you do not, you might be unable to read them yourself later if
9202 you happen to lose your private key.
9205 command saves messages in decrypted form, while the
9209 commands leave them encrypted.
9212 Note that neither S/MIME signing nor encryption applies to message
9213 subjects or other header fields yet.
9214 Thus they may not contain sensitive information for encrypted messages,
9215 and cannot be trusted even if the message content has been verified.
9216 When sending signed messages,
9217 it is recommended to repeat any important header information in the
9221 .\" .Ss "Using CRLs with S/MIME or SSL/TLS" {{{
9222 .Ss "Using CRLs with S/MIME or SSL/TLS"
9224 \*(OP Certification authorities (CAs) issue certificate revocation
9225 lists (CRLs) on a regular basis.
9226 These lists contain the serial numbers of certificates that have been
9227 declared invalid after they have been issued.
9228 Such usually happens because the private key for the certificate has
9230 because the owner of the certificate has left the organization that is
9231 mentioned in the certificate, etc.
9232 To seriously use S/MIME or SSL/TLS verification,
9233 an up-to-date CRL is required for each trusted CA.
9234 There is otherwise no method to distinguish between valid and
9235 invalidated certificates.
9236 \*(UA currently offers no mechanism to fetch CRLs, nor to access them on
9237 the Internet, so you have to retrieve them by some external mechanism.
9240 \*(UA accepts CRLs in PEM format only;
9241 CRLs in DER format must be converted, like, e.\|g.:
9244 .Dl $ openssl crl \-inform DER \-in crl.der \-out crl.pem
9247 To tell \*(UA about the CRLs, a directory that contains all CRL files
9248 (and no other files) must be created.
9253 variables, respectively, must then be set to point to that directory.
9254 After that, \*(UA requires a CRL to be present for each CA that is used
9255 to verify a certificate.
9258 .\" .Ss "Handling spam" {{{
9261 \*(OP \*(UA can make use of several spam interfaces for the purpose of
9262 identification of, and, in general, dealing with spam messages.
9263 A precondition of most commands in order to function is that the
9265 variable is set to one of the supported interfaces.
9266 Once messages have been identified as spam their (volatile)
9268 state can be prompted: the
9272 message specifications will address respective messages and their
9274 entries will be used when displaying the
9276 in the header display.
9281 rates the given messages and sets their
9284 If the spam interface offers spam scores those can also be displayed in
9285 the header display by including the
9295 will interact with the Bayesian filter of the chosen interface and learn
9296 the given messages as
9300 respectively; the last command can be used to cause
9302 of messages; it adheres to their current
9304 state and thus reverts previous teachings.
9309 will simply set and clear, respectively, the mentioned volatile
9311 message flag, without any interface interaction.
9318 .Va spam-interface Ns s
9322 require a running instance of the
9324 server in order to function, started with the option
9326 shall Bayesian filter learning be possible.
9328 only works via a local path-based
9330 socket, but otherwise the following will be equivalently fine:
9332 .Bd -literal -offset indent
9333 $ spamd -i localhost:2142 -i /tmp/.spamsock -d [-L] [-l]
9334 $ spamd --listen=localhost:2142 --listen=/tmp/.spamsock \e
9335 --daemonize [--local] [--allow-tell]
9339 Thereafter \*(UA can make use of these interfaces:
9341 .Bd -literal -offset indent
9342 $ \*(ua -Sspam-interface=spamd -Sspam-maxsize=500000 \e
9343 -Sspamd-socket=/tmp/.spamsock -Sspamd-user=
9345 $ \*(ua -Sspam-interface=spamc -Sspam-maxsize=500000 \e
9346 -Sspamc-command=/usr/local/bin/spamc \e
9347 -Sspamc-arguments="-U /tmp/.spamsock" -Sspamc-user=
9349 $ \*(ua -Sspam-interface=spamc -Sspam-maxsize=500000 \e
9350 -Sspamc-command=/usr/local/bin/spamc \e
9351 -Sspamc-arguments="-d localhost -p 2142" -Sspamc-user=
9355 Using the generic filter approach allows usage of programs like
9359 Here is an example for the former, requiring it to be accessible via
9362 .Bd -literal -offset indent
9363 $ \*(ua -Sspam-interface=filter -Sspam-maxsize=500000 \e
9364 -Sspamfilter-ham="bogofilter -n" \e
9365 -Sspamfilter-noham="bogofilter -N" \e
9366 -Sspamfilter-nospam="bogofilter -S" \e
9367 -Sspamfilter-rate="bogofilter -TTu 2>/dev/null" \e
9368 -Sspamfilter-spam="bogofilter -s" \e
9369 -Sspamfilter-rate-scanscore="1;^(.+)$"
9373 Because messages must exist on local storage in order to be scored (or
9374 used for Bayesian filter training), it is possibly a good idea to
9375 perform the local spam check last:
9377 .Bd -literal -offset indent
9378 define spamdelhook {
9380 spamset (header x-dcc-brand-metrics "bulk")
9381 # Server-side spamassassin(1)
9382 spamset (header x-spam-flag "YES")
9383 del :s # TODO we HAVE to be able to do `spamrate :u ! :sS'
9389 set folder-hook-FOLDER=spamdelhook
9393 See also the documentation for the variables
9394 .Va spam-interface , spam-maxsize ,
9395 .Va spamc-command , spamc-arguments , spamc-user ,
9396 .Va spamd-socket , spamd-user ,
9397 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
9400 .Va spamfilter-rate-scanscore .
9408 .\" .Ss "\*(UA shortly hangs on startup" {{{
9409 .Ss "\*(UA shortly hangs on startup"
9411 This can have two reasons, one is the necessity to wait for a file lock
9412 and can't be helped, the other being that \*(UA calls the function
9414 in order to query the nodename of the box (sometimes the real one is
9415 needed instead of the one represented by the internal variable
9417 You may have varying success by ensuring that the real hostname and
9421 or, more generally, that the name service is properly setup \(en
9424 return what you'd expect?
9425 Does this local hostname has a domain suffix?
9426 RFC 6762 standardized the link-local top-level domain
9430 .\" .Ss "I can't login to Google mail a.k.a. GMail" {{{
9431 .Ss "I can't login to Google mail a.k.a. GMail"
9433 Since 2014 some free service providers classify programs as
9435 unless they use a special authentification method (OAuth 2.0) which
9436 wasn't standardized for non-HTTP protocol authentication token query
9437 until August 2015 (RFC 7628).
9440 Different to Kerberos / GSSAPI, which is developed since the mid of the
9441 1980s, where a user can easily create a local authentication ticket for
9442 her- and himself with the locally installed
9444 program, that protocol has no such local part but instead requires
9445 a world-wide-web query to create or fetch a token; since there is no
9446 local cache this query has to be performed whenever \*(UA is invoked
9447 from the command line (in interactive sessions situation may differ).
9450 \*(UA doesn't support OAuth.
9451 Because of this it is necessary to declare \*(UA a
9453 (on the providers account web page) in order to read and send mail.
9454 However, it also seems possible to take the following steps instead:
9459 give the provider the number of a mobile phone,
9462 .Dq 2-Step Verification ,
9464 create an application specific password (16 characters), and
9466 use that special password instead of your real Google account password in
9467 S-nail (for more on that see the section
9468 .Sx "On URL syntax and credential lookup" ) .
9474 .\" .Sh "SEE ALSO" {{{
9492 .Xr spamassassin 1 ,
9519 M. Douglas McIlroy writes in his article
9520 .Dq A Research UNIX Reader: Annotated Excerpts \
9521 from the Programmer's Manual, 1971-1986
9524 command already appeared in First Edition
9528 .Bd -ragged -offset indent
9529 Electronic mail was there from the start.
9530 Never satisfied with its exact behavior, everybody touched it at one
9531 time or another: to assure the safety of simultaneous access, to improve
9532 privacy, to survive crashes, to exploit uucp, to screen out foreign
9533 freeloaders, or whatever.
9534 Not until v7 did the interface change (Thompson).
9535 Later, as mail became global in its reach, Dave Presotto took charge and
9536 brought order to communications with a grab-bag of external networks
9542 Mail was written in 1978 by Kurt Shoens and developed as part of the
9545 distribution until 1995.
9546 Mail has then seen further development in open source
9548 variants, noticeably by Christos Zoulas in
9550 Basing upon this Nail, later Heirloom Mailx, was developed by Gunnar
9551 Ritter in the years 2000 until 2008.
9552 Since 2012 S-nail is maintained by Steffen (Daode) Nurpmeso.
9553 This man page is derived from
9554 .Dq The Mail Reference Manual
9555 that was originally written by Kurt Shoens.
9562 .An "Christos Zoulas" ,
9563 .An "Gunnar Ritter" ,
9564 .An "Steffen Nurpmeso" Aq Mt s-nail-users@lists.sourceforge.net
9566 .Mt s-mailx@sdaoden.eu ) .
9572 The character set conversion uses and relies upon the
9575 Its functionality differs widely between the various system environments
9579 Limitations with POP3 mailboxes are:
9580 It is not possible to edit messages, they can only be copied and deleted.
9581 The line count for the header display is only appropriate if the entire
9582 message has been downloaded from the server.
9583 The status field of a message is maintained by the server between
9584 connections; some servers do not update it at all, and with a server
9587 command will not cause the message status to be reset.
9592 variable have no effect.
9593 It is not possible to rename or to remove POP3 mailboxes.
9600 is typed while a POP3 operation is in progress, \*(UA will wait
9601 until the operation can be safely aborted, and will then return to the
9602 command loop and print the prompt again.
9605 is typed while \*(UA is waiting for the operation to complete, the
9606 operation itself will be cancelled.
9607 In this case, data that has not been fetched yet will have to be fetched
9608 before the next command can be performed.
9609 If the cancelled operation was using an SSL/TLS encrypted channel,
9610 an error in the SSL transport will very likely result and render the
9611 connection unusable.
9614 As \*(UA is a mail user agent, it provides only basic SMTP services.
9615 If it fails to contact its upstream SMTP server, it will not make
9616 further attempts to transfer the message at a later time,
9617 and it does not leave other information about this condition than an
9618 error message on the terminal and an entry in
9620 This is usually not a problem if the SMTP server is located in the same
9621 local network as the computer on which \*(UA is run.
9622 However, care should be taken when using a remote server of an ISP;
9623 it might be better to set up a local SMTP server then which just acts as
9627 \*(UA immediately contacts the SMTP server (or
9629 It would not make much sense for \*(UA to defer outgoing mail since SMTP
9630 servers usually provide much more elaborated delay handling than \*(UA
9631 could perform as a client.
9639 from the distribution or the repository.
9641 After deleting some message of a POP3 mailbox the header summary falsely
9642 claims that there are no messages to display, you need to perform
9643 a scroll or dot movement to restore proper state.
9645 In threaded display a power user may encounter crashes very
9646 occasionally (this is may and very).