1 .\"@ nail.1 - S-nail(1) reference manual.
3 .\" Copyright (c) 1980, 1990, 1993
4 .\" The Regents of the University of California. All rights reserved.
6 .\" Gunnar Ritter. All rights reserved.
7 .\" Copyright (c) 2012 - 2015 Steffen (Daode) Nurpmeso <sdaoden@users.sf.net>.
9 .\" Redistribution and use in source and binary forms, with or without
10 .\" modification, are permitted provided that the following conditions
12 .\" 1. Redistributions of source code must retain the above copyright
13 .\" notice, this list of conditions and the following disclaimer.
14 .\" 2. Redistributions in binary form must reproduce the above copyright
15 .\" notice, this list of conditions and the following disclaimer in the
16 .\" documentation and/or other materials provided with the distribution.
17 .\" 3. All advertising materials mentioning features or use of this software
18 .\" must display the following acknowledgement:
19 .\" This product includes software developed by the University of
20 .\" California, Berkeley and its contributors.
21 .\" This product includes software developed by Gunnar Ritter
22 .\" and his contributors.
24 .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS 'AS IS' AND
25 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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33 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 .\" S-nail(1): v14.8.10 / 2016-08-20
49 .\" If not ~/.mailrc, it breaks POSIX compatibility. And adjust main.c.
54 .ds OU [no v15-compat]
55 .ds ID [v15 behaviour may differ]
66 .Nd send and receive Internet mail
78 .Op Fl a Ar attachment
81 .Op Fl q Ar quote-file
83 .Op Fl S Ar variable Ns Op Ns = Ns Ar value
88 .Op Fl Fl \: Ar mta-option ...
96 .Op Fl S Ar variable Ns Op Ns = Ns Ar value
99 .Op Fl Fl \: Ar mta-option ...
105 .Op Fl L Ar spec-list
106 .Op Fl r Ar from-addr
107 .Op Fl S Ar variable Ns Op Ns = Ns Ar value
110 .Op Fl Fl \: Ar mta-option ...
115 .Mx -toc -tree html pdf ps xhtml
118 .\" .Sh DESCRIPTION {{{
121 .Bd -filled -compact -offset indent
122 .Sy Compatibility note:
123 S-nail (\*(UA) will wrap up into \%S-mailx in v15.0 (circa 2018).
124 A partial set of compatibility options exist, tagged as \*(IN and \*(OU.
125 To choose upward compatible behaviour, please set the internal variable
127 Anything which will vanish in v15.0 is tagged \*(OB, and using
129 will print warnings for many use cases of obsolete features.
133 \*(UA is a mail processing system with a command syntax reminiscent of
135 with lines replaced by messages.
136 It is intended to provide the functionality of the POSIX
138 command and offers (mostly optional) extensions for line editing, IDNA,
139 MIME, S/MIME, SMTP and POP3 (and IMAP).
140 It is usable as a mail batch language.
142 .\" .Ss "Options" {{{
145 .Bl -tag -width ".Fl _ Ar _ccount"
150 command (see below) for
152 after the startup files have been read.
156 Attach the given file to the message.
157 The same filename conventions as described in the section
159 apply: shell word expansion is restricted to the tilde
164 not be accessible but contain a
166 character, then anything after the
168 is assumed to specify the input character set and anything before
170 the filename: this is the only option to specify the input character set
171 (and don't perform any character set conversion) for text attachments
172 from the command line, not using the
174 tilde escape command.
178 Make standard input and standard output line-buffered.
182 Send a blind carbon copy to
184 Can be used multiple times, but it is also possible to give
185 a comma-separated list of receivers in a single argument, proper shell
186 quoting provided, e.g.,
187 .Ql -b """qrec1 , rec2,rec3, Ex <am@ple>""" .
189 .Sx "On sending mail, and non-interactive mode" .
193 Send carbon copies to the given receiver(s).
194 Can be used multiple times.
206 variable which enables debug messages and disables message delivery,
207 among others; effectively turns almost any operation into a dry-run.
213 variable and thus discard messages with an empty message part body.
214 This is useful for sending messages from scripts.
218 Just check if mail is present in the system mailbox.
219 If yes, return an exit status of zero, a non-zero value otherwise.
223 Save the message to send in a file named after the local part of the
224 first recipient's address (instead of in
229 Read in the contents of the user's
231 (or the specified file) for processing;
232 when \*(UA is quit, it writes undeleted messages back to this file
236 Some special conventions are recognized for the string
238 which are documented for the
243 is not a direct argument to the flag
245 but is instead taken from the command line after option processing has
249 that starts with a hyphen, prefix it with a (relative) path, as in
250 .Ql ./-hyphenbox.mbox .
254 Print a header summary of all messages and exit.
255 A configurable summary view is available via the
261 Print a short usage summary.
262 Because of widespread use a
264 argument will have the same effect.
270 variable to ignore tty interrupt signals.
273 .It Fl L Ar spec-list
274 Print a header summary of only those messages that match the given
278 .Sx "Specifying messages"
283 option has been given in addition no header summary is produced,
284 but \*(UA will instead indicate via its exit status wether
290 note that any verbose output is suppressed in this mode and must instead
291 be enabled explicitly (e.g., by using the option
298 variable and thus inhibit initial display of message headers when
299 reading mail or editing a mail folder.
306 This option should be activated for \*(UA scripts that are invoked on
307 more than one machine, because the contents of that file may differ
309 (The same behaviour can be achieved by setting the
310 .Ev NAIL_NO_SYSTEM_RC
311 environment variable.)
315 Start the message with the contents of the specified file.
316 May be given in send mode only.
320 Any folder opened will be in read-only mode.
326 is a valid address then it specifies the envelope sender address to be
329 when a message is send.
332 include a user name, comments etc., then the components will be
333 separated and the name part will be passed to the MTA individually via
337 will also be assigned to the
339 variable, just as if additionally
341 had been specified (therefore affecting SMTP data transfer, too).
343 If instead an empty string is passed as
345 then the content of the variable
347 will be evaluated and used for this purpose whenever the MTA is
349 Note that \*(UA by default, without
351 that is, neither passes
355 flags to the MTA by itself.
358 .It Fl S Ar variable Ns Op = Ns value
359 Sets the internal option
361 and, in case of a value option, assigns
364 Even though variables set via
366 may be overwritten from within resource files,
367 the command line setting will be reestablished after all resource files
372 Specify the subject of the to-be-sent message.
376 The message to be sent is expected to contain a message header with
381 fields giving its recipients, which will be added to those given on the
383 If a message subject is specified via
385 then it'll be used in favour of one given on the command line.
397 Note you can also specify
401 and the envelope address possibly specified with the option
404 The following, which are normally created automatically based
405 upon the message context, can also be specified:
410 .Ql Mail-Followup-To:
411 (special address massage will however still occur for the latter).
415 Read the system mailbox of
417 (appropriate privileges presumed), and
420 in some aspects, e.g. in respect to
429 Print \*(UA's version and exit.
435 option enables display of some informational context messages.
436 Using it twice increases the level of verbosity.
442 to the list of commands to be executed before normal operation starts.
446 .Va batch-exit-on-error ;
447 the only possibility to execute commands in non-interactive mode when
448 reading startup files is actively prohibited.
454 even if not in interactive mode.
458 This sets several variables to prepare \*(UA for working in (most likely
459 non-interactive) batch mode:
471 It also enables processing of
472 .Sx "TILDE ESCAPES" .
473 E.g., the following should send an email message to
475 .Bd -literal -offset indent
476 $ LC_ALL=C printf 'm bob\en~s ubject\enText\en.\enx\en' | \e
477 LC_ALL=C MAILRC=/dev/null \*(ua -n -# -Snosave
482 This flag forces termination of option processing in order to prevent
485 It also forcefully puts \*(UA into send mode, see
486 .Sx "On sending mail, and non-interactive mode" .
490 In the above list of supported command line options,
491 .Fl D , d , E , i , N
494 are implemented by means of setting the respective option, as via
497 .Op Ar mta-option ...
499 arguments that are given at the end of the command line after a
501 separator will be passed through to the mail-transfer-agent (MTA) and
502 persist for an entire (interactive) session \(en if the setting of
504 allows their recognition;
505 MTA arguments can also be specified in the variable
506 .Va sendmail-arguments ;
507 find MTA interaction described in more detail in the documentation of
509 MTA arguments are ignored when mail is send via SMTP data transfer.
512 .\" .Ss "A starter" {{{
515 \*(UA is a direct descendant of
517 Mail, a successor of the Research
520 .Dq was there from the start
525 Mail reference manual begins with the following words:
527 .Bd -ragged -offset indent
528 Mail provides a simple and friendly environment for sending and
530 It divides incoming mail into its constituent messages and allows the
531 user to deal with them in any order.
532 In addition, it provides a set of
534 -like commands for manipulating messages and sending mail.
535 Mail offers the user simple editing capabilities to ease the composition
536 of outgoing messages, as well as providing the ability to define and
537 send to names which address groups of users.
541 \*(UA is thus the user side of the
543 mail system, whereas the system side (mail-transfer-agent, MTA) was
544 traditionally taken by
550 are often used for this purpose instead.
551 If the \*(OPal SMTP is included in the
553 of \*(UA then the system side is not a mandatory precondition for mail
557 Because \*(UA strives for compliance with POSIX
559 it is likely that some configuration settings have to be adjusted before
560 using it is a smooth experience.
563 file already bends those standard settings a bit towards more user
564 friendliness and safety, e.g., it sets the
568 variables in order to suppress the automatic moving of messages to
570 that would otherwise occur (see
571 .Sx "Message states" )
574 to not remove empty files in order not to mangle file permissions when
575 files eventually get recreated.
578 option so that by default file grouping (via the
580 prefix as documented also for
585 contains some further suggestions.
588 .\" .Ss "On sending mail, and non-interactive mode" {{{
589 .Ss "On sending mail, and non-interactive mode"
591 To send a message to one or more people, using a local
592 mail-transfer-agent (MTA; the executable path can be set via
594 or the \*(OPal builtin SMTP (set and see the variable
596 transport to actually deliver the generated mail message, \*(UA can be
597 invoked with arguments which are the names of people to whom the mail
600 .Bd -literal -offset indent
601 $ \*(ua -s Subject -a attachm.ent bill@host1 'Bob <bob@host2>'
602 # But... try it in an isolated dry-run mode first
603 $ LC_ALL=C MAILRC=/dev/null \e
604 \*(ua -n -d -vv -Sfrom="me <he@re>" \e
605 -b bcc@exam.ple -c cc@exam.ple \e
606 -s Subject -. "(Lovely) Bob <bob@host2>"
610 The command line options
614 can be used to add (blind) carbon copy receivers.
615 Almost always lists of addresses can be given where an address is
617 whereas comma-separated lists should be given, e.g.,
618 .Ql -c """r1@exam.ple , r2@exam.ple,r3@exam.ple""" ,
619 that very example could also be given as the whitespace-separated list
620 .Ql -c """r1@exam.ple r2@exam.ple r3@exam.ple""" ,
621 but which for obvious reasons would not work for
622 .Ql -c """R1 <r1@exam.ple>, R2 (heh!) <r2@exam.ple>""" .
625 The user is then expected to type in the message contents.
626 In this compose mode \*(UA treats lines beginning with the character
628 special \(en these are so-called
630 which can be used to read in files, process shell commands, add and edit
631 attachments and more; e.g., the tilde escape
633 will start the text editor to revise the message in it's current state,
635 allows editing of the message recipients and
637 gives an overview of available tilde escapes.
640 at the beginning of an empty line leaves compose mode and causes the
641 message to be send, whereas typing control-C
643 twice will abort the current letter (saving its contents in the file
651 A number of variables can be used to alter default behavior; e.g.,
656 will automatically startup a text editor when compose mode is entered,
658 will cause the user to be prompted actively for carbon-copy recipients
661 option will allow leaving compose mode by writing a line consisting
666 Very important, though, is to define which
668 may be used when sending messages, usually by setting the option
671 having read the section
672 .Sx "The mime.types files"
673 to understand how the MIME-type of outgoing attachments is classified
674 and the knowledge that messages are sent asynchronously unless
676 is set: only with it MTA delivery errors will be recognizable.
681 is often necessary (e.g., in conjunction with
683 or desirable, you may want to do some dry-run tests before you go.
684 Saving a copy of the sent messages in a
686 may also be desirable \(en as for most mailbox file targets some
687 special conventions are recognized, see the
689 command for more on that.
691 .Sx "On URL syntax and credential lookup"
692 will spread some light on the
694 variable chains as well as on using URLs for accessing protocol-specific
699 contains an example configuration for sending messages via some of the
700 well-known public mail providers;
701 note it also gives a compact overview on how to setup a secure SSL/TLS
705 Message recipients (as specified on the command line or defined in
710 may not only be email addressees but can also be names of mailboxes and
711 even complete shell command pipe specifications.
712 Proper (shell) quoting is necessary, e.g., to embed whitespace characters.
713 (Recall that \*(UA deals with mail standards, therefore those define the
714 rules with which content is interpreted.)
717 is not set then only network addresses (see
719 for a description of mail addresses) and plain user names (including MTA
720 aliases) may be used, other types will be filtered out, giving a warning
723 .\" When changing any of the following adjust any RECIPIENTADDRSPEC;
724 .\" grep the latter for the complete picture
728 is set then extended recipient addresses will optionally be accepted:
729 Any name which starts with a vertical bar
731 character specifies a command pipe \(en the command string following the
733 is executed and the message is sent to its standard input;
734 Likewise, any name that starts with the character slash
736 or the character sequence dot slash
738 is treated as a file, regardless of the remaining content.
739 Any other name which contains an at sign
741 character is treated as a network address;
742 Any other name which starts with a plus sign
744 character specifies a mailbox name;
745 Any other name which contains a slash
747 character but no exclamation mark
751 character before also specifies a mailbox name;
752 What remains is treated as a network address.
754 .Bd -literal -offset indent
755 $ echo bla | \*(ua -Sexpandaddr -s test ./mbox.mbox
756 $ echo bla | \*(ua -Sexpandaddr -s test '|cat >> ./mbox.mbox'
757 $ echo safe | LC_ALL=C MAILRC=/dev/null \e
758 \*(ua -n -Sv15-compat -Ssendwait -Snosave \e
759 -Sexpandaddr=fail,-all,+addr -s test \e
764 It is possible to create personal distribution lists via the
766 command, so that, for instance, the user can send mail to
768 and have it go to a group of people:
771 .Dl alias cohorts bill jkf mark kridle@ucbcory ~/mail/cohorts.mbox
774 Please note that this mechanism has nothing in common with the system
775 wide aliases that may be used by the local MTA (mail-transfer-agent),
776 which are subject to the
780 and are often tracked in a file
786 Personal aliases will be expanded by \*(UA before the message is sent,
787 and are thus a convenient alternative to specifying each addressee by
791 To avoid environmental noise scripts should
793 \*(UA from any configuration files and create a script-local
794 environment, either by pointing the
796 variable to a custom configuration file, or by using the
798 command line option to specify variables:
800 .Bd -literal -offset indent
801 $ env LC_ALL=C MAILRC=/dev/null password=NOTSECRET \e
802 \*(ua -n -Sv15-compat -Ssendwait -Snosave \e
803 -Sexpandaddr=fail,-all,+addr \e
804 -S 'smtp=smtps://mylogin@some.host:465' -Ssmtp-auth=login \e
805 -S 'from=scriptreply@domain' \e
806 -s 'subject' -a attachment_file \e
807 -. "Recipient 1 <recipient1@domain>" recipient2@domain \e
812 In interactive mode, which is introduced in the next section, messages
813 can be send by calling the
815 command with a list of recipient addresses \(em the semantics are
816 completely identical to non-interactive message sending, except that
817 it is likely necessary to separate recipient lists with commas:
819 .Bd -literal -offset indent
820 $ \*(ua -d -Squiet -Semptystart
821 "/var/spool/mail/user": 0 messages
822 ? mail "Recipient 1 <recipient1@domain>", recipient2@domain
823 ? # Will do the right thing (tm)
824 ? m recipient1@domain recipient2@domain
828 .\" .Ss "On reading mail, and interactive mode" {{{
829 .Ss "On reading mail, and interactive mode"
831 When invoked without addressees \*(UA enters interactive mode in which
833 When used like that the user's system mailbox (see the command
835 for an in-depth description of the different mailbox types that exist)
836 is read in and a one line header of each message therein is displayed.
837 The visual style of this summary of
839 can be adjusted through the variable
841 and the possible sorting criterion via
843 If the initially opened mailbox is empty \*(UA will instead exit
844 immediately (after displaying a message) unless the variable
853 will give a listing of all available commands and
855 will give a summary of some common ones.
856 If the \*(OPal documentation strings are available one can type
858 and see the actual expansion of
860 and what it's purpose is, i.e., commands can be abbreviated
861 (note that POSIX defines some abbreviations, so that the alphabetical
862 order of commands doesn't necessarily relate to the abbreviations; it is
863 possible to define overwrites with the
868 Messages are given numbers (starting at 1) which uniquely identify
869 messages; the current message \(en the
871 \(en will either be the first new message, or the first unread message,
872 or the first message of the mailbox; the option
874 will instead cause usage of the last message for this purpose.
879 ful of header summaries containing the
883 will print only the summaries of the given messages, defaulting to the
887 Messages can be printed with the
891 By default the current message
893 is printed, but like with most other commands it is possible to give
894 a fancy message specification (see
895 .Sx "Specifying messages" ) ,
898 will display all unread messages,
903 will print the messages 1 and 5,
905 will print the messages 1 through 5, and
909 will print the last and the next message, respectively.
910 By the way, using the command
912 in conjunction with a message specification is the way to perform
913 searching in \*(UA: the following will print the header summaries of all
914 messages which contain the given string in their subject, for example:
917 .Dl ? from """@Some subject to search for"""
920 In the default setup all header fields of a message will be printed,
921 but this can be changed: either by blacklisting a list of fields via
923 or by whitelisting only a given list with the
926 .Ql Ic \:retain Ns \0date from to cc subject .
927 In order to print all header fields of a message regardless of currently
928 active ignore or retain lists, use the command
932 controls wether and when \*(UA will use the configured
934 for printing instead of directly writing to the terminal (generally
936 Note that historically the global
938 not only adjusts the list of displayed headers, but also sets
942 Dependent upon the configuration a
943 .Sx "Command line editor"
944 aims at making user experience with the many
947 When reading the system mailbox or when
951 specified a mailbox explicitly prefixed with the special
953 modifier (propagating the mailbox to a primary one) then messages which
954 have been read will be moved to a secondary mailbox, the user's
956 file, automatically when the mailbox is left, either by changing the
957 active mailbox or by quitting \*(UA (also see
958 .Sx "Message states" )
959 \(en this automatic moving from a system or primary to the secondary
960 mailbox is not performed when the variable
965 After examining a message the user can also
969 to the sender and all recipients or
971 exclusively to the sender(s).
976 Note that when replying to or forwarding a message recipient addresses
977 will be stripped from comments and names unless the option
980 Deletion causes \*(UA to forget about the message;
981 This is not irreversible, though, one can
983 the message by giving its number,
984 or the \*(UA session can be ended by giving the
989 To end a mail processing session one may either issue
991 to cause a full program exit, which possibly includes
992 automatic moving of read messages to
994 as well as updating the \*(OPal command line editor history file,
997 instead in order to prevent any of these actions.
1000 .\" .Ss "HTML mail and MIME attachments" {{{
1001 .Ss "HTML mail and MIME attachments"
1003 Messages which are HTML-only get more and more common and of course many
1004 messages come bundled with a bouquet of MIME attachments.
1005 Whereas \*(UA \*(OPally supports a simple HTML-to-text converter to deal
1006 with HTML messages (see
1007 .Sx "The mime.types files" ) ,
1008 it normally can't deal with any of these itself, but instead programs
1009 need to become registered to deal with specific MIME types or file
1011 These programs may either prepare plain text versions of their input
1012 in order to enable \*(UA to display the content on the terminal,
1013 or display the content themselves, for example in a graphical window.
1016 To install an external handler program for a specific MIME type set an
1018 .Va pipe-TYPE/SUBTYPE
1019 variable; to instead define a handler for a specific file extension set
1022 variable \(en these handlers take precedence.
1023 \*(OPally \*(UA supports mail user agent configuration as defined in
1024 RFC 1524; this mechanism, documented in the section
1025 .Sx "The Mailcap files" ,
1026 will be queried for display or quote handlers if none of the former two
1027 .\" TODO v15-compat "will be" -> "is"
1028 did; it will be the sole source for handlers of other purpose.
1029 A last source for handlers may be the MIME type definition itself, if
1030 the \*(UA specific type-marker extension was used when defining the type
1033 (Many of the builtin MIME types do so by default.)
1037 .Va mime-counter-evidence
1038 can be set to improve dealing with faulty MIME part declarations as are
1039 often seen in real-life messages.
1040 E.g., to display a HTML message inline (that is, converted to a more
1041 fancy plain text representation than the builtin converter is capable to
1042 produce) with either of the text-mode browsers
1046 teach \*(UA about MathML documents and make it display them as plain
1047 text, and to open PDF attachments in an external PDF viewer,
1048 asynchronously and with some other magic attached:
1050 .Bd -literal -offset indent
1051 if $features !@ HTML-FILTER
1052 #set pipe-text/html="elinks -force-html -dump 1"
1053 set pipe-text/html="lynx -stdin -dump -force_html"
1054 # Display HTML as plain text instead
1055 #set pipe-text/html=@
1057 mimetype '@ application/mathml+xml mathml'
1058 set pipe-application/pdf="@&=@ \e
1059 trap \e"rm -f \e\e\e"${NAIL_FILENAME_TEMPORARY}\e\e\e"\e" EXIT;\e
1060 trap \e"trap \e\e\e"\e\e\e" INT QUIT TERM; exit 1\e" \e INT QUIT TERM;\e
1061 xpdf \e"${NAIL_FILENAME_TEMPORARY}\e""
1065 Note: special care must be taken when using such commands as mail
1066 viruses may be distributed by this method: if messages of type
1067 .Ql application/x-sh
1068 or files with the extension
1070 were blindly filtered through the shell, for example, a message sender
1071 could easily execute arbitrary code on the system \*(UA is running on.
1072 For more on MIME, also in respect to sending of messages, see the
1074 .Sx "The mime.types files" ,
1075 .Sx "The Mailcap files"
1080 .\" .Ss "Mailing lists" {{{
1083 \*(UA offers some support to ease handling of mailing lists.
1086 promotes all given arguments to known mailing lists, and
1088 sets their subscription attribute, creating them first as necessary.
1093 automatically, but only resets the subscription attribute.)
1094 Using the commands without arguments will print out (a subset of) all
1095 currently defined mailing lists.
1100 can be used to mark out messages with configured list addresses
1101 in the header display.
1104 \*(OPally mailing lists may also be specified as (extended) regular
1105 expressions, which allows matching of many addresses with a single
1107 However, all fully qualified list addresses are matched via a fast
1108 dictionary, whereas expressions are placed in (a) list(s) which is
1109 (are) matched sequentially.
1111 .Bd -literal -offset indent
1112 set followup-to followup-to-honour=ask-yes reply-to-honour=ask-yes
1113 mlist a1@b1.c1 a2@b2.c2 .*@lists.c3$
1114 mlsubscribe a4@b4.c4 exact@lists.c3
1119 .Va followup-to-honour
1121 .Ql Mail-\:Followup-\:To:
1122 header is honoured when the message is being replied to (via
1128 controls wether this header is created when sending mails; it will be
1129 created automatically for a couple of reasons, too, like when the
1131 .Dq mailing list specific
1136 is used to respond to a message with its
1137 .Ql Mail-Followup-To:
1141 A difference in between the handling of known and subscribed lists is
1142 that the address of the sender is usually not part of a generated
1143 .Ql Mail-Followup-To:
1144 when addressing the latter, whereas it is for the former kind of lists.
1145 Usually because there are exceptions: say, if multiple lists are
1146 addressed and not all of them are subscribed lists.
1148 For convenience \*(UA will, temporarily, automatically add a list
1149 address that is presented in the
1151 header of a message that is being responded to to the list of known
1153 Shall that header have existed \*(UA will instead, dependend on the
1155 .Va reply-to-honour ,
1158 for this purpose in order to accept a list administrators' wish that
1159 is supposed to have been manifested like that (but only if it provides
1160 a single address which resides on the same domain as what is stated in
1164 .\" .Ss "Resource files" {{{
1165 .Ss "Resource files"
1167 Upon startup \*(UA reads in several resource files:
1169 .Bl -tag -width ".It Pa _AIL_EXTRA_R_"
1172 System wide initialization file.
1173 Reading of this file can be suppressed, either by using the
1175 command line option, or by setting the environment variable
1176 .Ev NAIL_NO_SYSTEM_RC .
1180 File giving initial commands.
1181 A different file can be chosen by setting the environment variable
1184 .It Va NAIL_EXTRA_RC
1185 Can be used to define an optional startup file to be read after
1187 This variable is only honoured in certain circumstances (see its
1188 documentation for more).
1192 The content of these files is interpreted as follows:
1195 .Bl -bullet -compact
1197 A lines' leading whitespace is removed.
1199 Empty lines are ignored.
1201 Any other line is interpreted as a command.
1202 It may be spread over multiple input lines if the newline character is
1204 by placing a backslash character
1206 as the last character of the line; whereas any leading whitespace of
1207 follow lines is ignored, trailing whitespace before a escaped newline
1208 remains in the input.
1210 If the line (content) starts with the number sign
1212 then it is a comment-command \(en a real command! \(en and also ignored.
1213 This command is the only form of comment that is understood.
1219 .Bd -literal -offset indent
1220 # This line is a comment command. And y\e
1221 es, it is really continued here.
1228 .\" .Ss "Character sets" {{{
1229 .Ss "Character sets"
1231 \*(OP \*(UA detects the character set of the terminal by using
1232 mechanisms that are controlled by the
1237 should give an overview); the \*(UA internal variable
1239 will be set to the detected terminal character set accordingly
1240 and will thus show up in the output of the commands
1246 However, a user supplied
1248 value is not overwritten by this detection mechanism: this
1250 must be used if the detection doesn't work properly,
1251 and it may be used to adjust the name of the locale character set.
1252 E.g., on BSD systems one may use a locale with the character set
1253 ISO8859-1, which is not a valid name for this character set; to be on
1254 the safe side, one may set
1256 to the correct name, which is ISO-8859-1.
1259 Note that changing the value doesn't mean much beside that,
1260 since several aspects of the real character set are implied by the
1261 locale environment of the system,
1262 and that stays unaffected by the content of an overwritten
1265 (This is mostly an issue when interactively using \*(UA, though.
1266 It is actually possible to send mail in a completely
1268 locale environment, an option that \*(UA's test-suite uses excessively.)
1271 If no character set conversion capabilities have been compiled into
1274 doesn't include the term
1278 will be the only supported character set,
1279 it is simply assumed that it can be used to exchange 8-bit messages,
1280 and the rest of this section does not apply;
1281 it may however still be necessary to explicitly set it if automatic
1282 detection fails, since in that case it defaults to the mentioned
1283 .\" (Keep in SYNC: ./nail.1:"Character sets", ./nail.h:CHARSET_*!)
1287 When reading messages, their text is converted into
1289 as necessary in order to display them on the users terminal.
1290 Unprintable characters and invalid byte sequences are detected
1291 and replaced by proper substitution characters (unless the variable
1293 was set once \*(UA was started).
1295 .Va charset-unknown-8bit
1296 to deal with another hairy aspect of message interpretation.
1299 When sending messages all their parts and attachments are classified.
1300 Whereas no character set conversion is performed on those parts which
1301 appear to be binary data,
1302 the character set being used must be declared within the MIME header of
1303 an outgoing text part if it contains characters that do not conform to
1304 the set of characters that are allowed by the email standards.
1305 Permissible values for character sets can be declared using the
1309 which defines a catch-all last-resort fallback character set that is
1310 implicitly appended to the list of character-sets in
1314 When replying to a message and the variable
1315 .Va reply-in-same-charset
1316 is set then the character set of the message being replied to is tried
1318 And it is also possible to make \*(UA work even more closely related to
1319 the current locale setting automatically by using the variable
1320 .Va sendcharsets-else-ttycharset ,
1321 please see there for more information.
1324 All the specified character sets are tried in order unless the
1325 conversion of the part or attachment succeeds.
1326 If none of the tried (8-bit) character sets is capable to represent the
1327 content of the part or attachment,
1328 then the message will not be sent and its text will optionally be
1332 In general, if the message
1333 .Dq Cannot convert from a to b
1334 appears, either some characters are not appropriate for the currently
1335 selected (terminal) character set,
1336 or the needed conversion is not supported by the system.
1337 In the first case, it is necessary to set an appropriate
1339 locale and/or the variable
1343 The best results are usually achieved when \*(UA is run in a UTF-8
1344 locale on a UTF-8 capable terminal, in which case the full Unicode
1345 spectrum of characters is available.
1346 In this setup characters from various countries can be displayed,
1347 while it is still possible to use more simple character sets for sending
1348 to retain maximum compatibility with older mail clients.
1351 On the other hand the POSIX standard defines a locale-independent 7-bit
1352 .Dq portable character set
1353 that should be used when overall portability is an issue, the even more
1354 restricted subset named
1355 .Dq portable filename character set
1356 consisting of A-Z, a-z, 0-9, period
1365 .\" .Ss "Message states" {{{
1366 .Ss "Message states"
1368 \*(UA differentiates in between several different message states;
1369 the current state will be reflected in header summary displays if
1371 is configured to do so (via the internal variable
1373 and messages can also be selected and be acted upon depending on their
1375 .Sx "Specifying messages" ) .
1376 When operating on the system mailbox or in primary mailboxes opened with
1381 special actions, like the automatic moving of messages to the secondary
1383 mailbox may be applied when the mailbox is left (also implicitly via
1384 a successful exit of \*(UA, but not if the special command
1386 is used) \(en however, because this may be irritating to users which
1389 mail-user-agents, the default global
1395 variables in order to suppress this behaviour.
1397 .Bl -tag -width ".It Ql _reserved"
1399 Message has neither been viewed nor moved to any other state.
1400 Such messages are retained even in the system mailbox.
1403 Message has neither been viewed nor moved to any other state, but the
1404 message was present already when the mailbox has been opened last:
1405 Such messages are retained even in the system mailbox.
1408 The message has been processed by one of the following commands:
1428 commands may also cause the next message to be marked as read, depending
1434 command is used, messages that are in the system mailbox or in mailboxes
1435 which were opened with the special
1439 state when the mailbox is left will be saved in
1446 The message has been processed by one of the following commands:
1452 can be used to access such messages.
1455 The message has been processed by a
1457 command and it will be retained in its current location.
1460 The message has been processed by one of the following commands:
1466 command is used, messages that are in the system mailbox or in mailboxes
1467 which were opened with the special
1471 state when the mailbox is left will be deleted; they will be saved in
1479 .\" .Ss "Specifying messages" {{{
1480 .Ss "Specifying messages"
1487 can be given a list of message numbers as arguments to apply to a number
1488 of messages at once.
1491 deletes messages 1 and 2,
1494 will delete the messages 1 through 5.
1495 In sorted or threaded mode (see the
1499 will delete the messages that are located between (and including)
1500 messages 1 through 5 in the sorted/threaded order, as shown in the
1502 Multiple colon modifiers can be joined into one, e.g.,
1504 The following special message names exist:
1506 .Bl -tag -width ".It Ar _n_u"
1512 All old messages (any not in state
1535 All answered messages
1540 All messages marked as draft.
1542 \*(OP All messages classified as spam.
1544 \*(OP All messages with unsure spam classification.
1546 The current message, the so-called
1549 The message that was previously the current message.
1551 The parent message of the current message,
1552 that is the message with the Message-ID given in the
1554 field or the last entry of the
1556 field of the current message.
1558 The next previous undeleted message,
1559 or the next previous deleted message for the
1562 In sorted/threaded mode,
1563 the next previous such message in the sorted/threaded order.
1565 The next undeleted message,
1566 or the next deleted message for the
1569 In sorted/threaded mode,
1570 the next such message in the sorted/threaded order.
1572 The first undeleted message,
1573 or the first deleted message for the
1576 In sorted/threaded mode,
1577 the first such message in the sorted/threaded order.
1580 In sorted/threaded mode,
1581 the last message in the sorted/threaded order.
1585 selects the message addressed with
1589 is any other message specification,
1590 and all messages from the thread that begins at it.
1591 Otherwise it is identical to
1596 the thread beginning with the current message is selected.
1601 All messages that were included in the message list for the previous
1604 .It Ar / Ns Ar string
1605 All messages that contain
1607 in the subject field (case ignored).
1614 the string from the previous specification of that type is used again.
1616 .It Xo Op Ar @ Ns Ar name-list Ns
1619 All messages that contain the given case-insensitive search
1621 ession; if the \*(OPal regular expression (see
1623 support is available
1625 will be interpreted as (an extended) one if any of the
1627 (extended) regular expression characters is seen.
1629 .Ar @ Ns Ar name-list
1630 part is missing, the search is restricted to the subject field body,
1633 specifies a comma-separated list of header fields to search, as in
1635 .Dl '@to,from,cc@Someone i ought to know'
1637 In order to search for a string that includes a
1639 (commercial at) character the
1641 is effectively non-optional, but may be given as the empty string.
1642 Some special header fields may be abbreviated:
1656 respectively and case-insensitively.
1661 can be used to search in (all of) the header(s) of the message, and the
1670 can be used to perform full text searches \(en whereas the former
1671 searches only the body, the latter also searches the message header.
1673 This message specification performs full text comparison, but even with
1674 regular expression support it is almost impossible to write a search
1675 expression that savely matches only a specific address domain.
1676 To request that the content of the header is treated as a list of
1677 addresses, and to strip those down to the plain email address which the
1678 search expression is to be matched against, prefix the header name
1679 (abbreviation) with a tilde
1682 .Dl @~f@@a\e.safe\e.domain\e.match$
1686 .Dq any substring matches
1689 header, which will match addresses (too) even if
1691 is set (and POSIX says
1692 .Dq any address as shown in a header summary shall be matchable in this form ) ;
1695 variable is set, only the local part of the address is evaluated
1696 for the comparison, not ignoring case, and the setting of
1698 is completely ignored.
1699 For finer control and match boundaries use the
1701 search expression; the \*(OPal IMAP-style
1703 expression can also be used if substring matches are desired.
1707 \*(OP IMAP-style SEARCH expressions may also be used.
1708 This addressing mode is available with all types of folders;
1709 \*(UA will perform the search locally as necessary.
1710 Strings must be enclosed by double quotes
1712 in their entirety if they contain white space or parentheses;
1713 within the quotes, only backslash
1715 is recognized as an escape character.
1716 All string searches are case-insensitive.
1717 When the description indicates that the
1719 representation of an address field is used,
1720 this means that the search string is checked against both a list
1723 .Bd -literal -offset indent
1724 (\*qname\*q \*qsource\*q \*qlocal-part\*q \*qdomain-part\*q)
1729 and the addresses without real names from the respective header field.
1730 These search expressions can be nested using parentheses, see below for
1734 .Bl -tag -compact -width ".It Ar _n_u"
1735 .It Ar ( criterion )
1736 All messages that satisfy the given
1738 .It Ar ( criterion1 criterion2 ... criterionN )
1739 All messages that satisfy all of the given criteria.
1741 .It Ar ( or criterion1 criterion2 )
1742 All messages that satisfy either
1747 To connect more than two criteria using
1749 specifications have to be nested using additional parentheses,
1751 .Ql (or a (or b c)) ,
1755 .Ql ((a or b) and c) .
1758 operation of independent criteria on the lowest nesting level,
1759 it is possible to achieve similar effects by using three separate
1763 .It Ar ( not criterion )
1764 All messages that do not satisfy
1766 .It Ar ( bcc \*q Ns Ar string Ns Ar \*q )
1767 All messages that contain
1769 in the envelope representation of the
1772 .It Ar ( cc \*q Ns Ar string Ns Ar \*q )
1773 All messages that contain
1775 in the envelope representation of the
1778 .It Ar ( from \*q Ns Ar string Ns Ar \*q )
1779 All messages that contain
1781 in the envelope representation of the
1784 .It Ar ( subject \*q Ns Ar string Ns Ar \*q )
1785 All messages that contain
1790 .It Ar ( to \*q Ns Ar string Ns Ar \*q )
1791 All messages that contain
1793 in the envelope representation of the
1796 .It Ar ( header name \*q Ns Ar string Ns Ar \*q )
1797 All messages that contain
1802 .It Ar ( body \*q Ns Ar string Ns Ar \*q )
1803 All messages that contain
1806 .It Ar ( text \*q Ns Ar string Ns Ar \*q )
1807 All messages that contain
1809 in their header or body.
1810 .It Ar ( larger size )
1811 All messages that are larger than
1814 .It Ar ( smaller size )
1815 All messages that are smaller than
1819 .It Ar ( before date )
1820 All messages that were received before
1822 which must be in the form
1826 denotes the day of the month as one or two digits,
1828 is the name of the month \(en one of
1829 .Ql Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ,
1832 is the year as four digits, e.g.,
1836 All messages that were received on the specified date.
1837 .It Ar ( since date )
1838 All messages that were received since the specified date.
1839 .It Ar ( sentbefore date )
1840 All messages that were sent on the specified date.
1841 .It Ar ( senton date )
1842 All messages that were sent on the specified date.
1843 .It Ar ( sentsince date )
1844 All messages that were sent since the specified date.
1846 The same criterion as for the previous search.
1847 This specification cannot be used as part of another criterion.
1848 If the previous command line contained more than one independent
1849 criterion then the last of those criteria is used.
1853 .\" .Ss "On URL syntax and credential lookup" {{{
1854 .Ss "On URL syntax and credential lookup"
1856 \*(IN For accessing protocol-specific resources usage of Uniform
1857 Resource Locators (URL, RFC 1738) has become omnipresent.
1858 \*(UA expects and understands URLs in the following form;
1861 denote optional parts, optional either because there also exist other
1862 ways to define the information in question or because support of the
1863 part is protocol-specific (e.g.,
1865 is used by the IMAP protocol but not by POP3);
1870 are specified they must be given in URL percent encoded form (RFC 3986;
1878 .Dl PROTOCOL://[USER[:PASSWORD]@]server[:port][/path]
1881 Note that these \*(UA URLs most often don't conform to any real
1882 standard, but instead represent a normalized variant of RFC 1738 \(en
1883 they are not used in data exchange but only ment as a compact,
1884 easy-to-use way of defining and representing information in
1885 a well-known notation.
1888 Many internal variables of \*(UA exist in multiple versions, called
1889 variable chains for the rest of this document: the plain
1894 .Ql variable-USER@HOST .
1901 had been specified in the respective URL, otherwise it refers to the plain
1907 that had been found when doing the user chain lookup as is described
1910 will never be in URL percent encoded form, wether it came from an URL or
1911 not; i.e., values of
1912 .Sx "INTERNAL VARIABLES"
1913 must not be URL percent encoded.
1916 For example, wether an hypothetical URL
1917 .Ql smtp://hey%3Ayou@our.house
1918 had been given that includes a user, or wether the URL was
1919 .Ql smtp://our.house
1920 and the user had been found differently, to lookup the variable chain
1921 .Va smtp-use-starttls
1922 \*(UA first looks for wether
1923 .Ql smtp-\:use-\:starttls-\:hey:you@our.house
1924 is defined, then wether
1925 .Ql smtp-\:use-\:starttls-\:our.house
1926 exists before finally ending up looking at the plain variable itself.
1929 \*(UA obeys the following logic scheme when dealing with the
1930 necessary credential informations of an account:
1936 has been given in the URL the variables
1940 are looked up; if no such variable(s) can be found then \*(UA will,
1941 when enforced by the \*(OPal variables
1942 .Va netrc-lookup-HOST
1949 specific entry which provides a
1951 name: this lookup will only succeed if unambiguous (one possible matching
1955 If there is still no
1957 then \*(UA will fall back to the user who is supposed to run \*(UA:
1958 either the name that has been given with the
1960 command line option (or, equivalently, but with less precedence, the
1961 environment variable
1966 The identity of this user has been fixated during \*(UA startup and is
1967 known to be a valid user on the current host.
1970 Authentication: unless otherwise noted this will lookup the
1971 .Va PROTOCOL-auth-USER@HOST , PROTOCOL-auth-HOST , PROTOCOL-auth
1972 variable chain, falling back to a protocol-specific default should this
1978 has been given in the URL, then if the
1980 has been found through the \*(OPal
1982 then that may have already provided the password, too.
1983 Otherwise the variable chain
1984 .Va password-USER@HOST , password-HOST , password
1985 is looked up and used if existent.
1987 \*(OP Then if any of the variables of the chain
1988 .Va agent-shell-lookup-USER@HOST , agent-shell-lookup-HOST , \
1990 is set the shell command specified therein is run and the output (less
1991 newline characters) will be used as the password.
1992 It is perfectly valid for such an agent to simply not return any data,
1993 in which case the password lookup is continued somewhere else;
1994 Any command failure is treated as a hard error, however.
1996 Afterwards the complete \*(OPal variable chain
1997 .Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup
2001 cache is searched for a password only (multiple user accounts for
2002 a single machine may exist as well as a fallback entry without user
2003 but with a password).
2005 If at that point there is still no password available, but the
2006 (protocols') chosen authentication type requires a password, then in
2007 interactive mode the user will be prompted on the terminal.
2012 S/MIME verification works relative to the values found in the
2016 header field(s), which means that the values of
2017 .Va smime-sign , smime-sign-cert , smime-sign-include-certs
2019 .Va smime-sign-message-digest
2020 will not be looked up using the
2024 chains from above but instead use the corresponding values from the
2025 message that is being worked on.
2026 In unusual cases multiple and different
2030 combinations may therefore be involved \(en on the other hand those
2031 unusual cases become possible.
2032 The usual case is as short as:
2035 .Dl set smtp=smtp://USER:PASS@HOST smtp-use-starttls \e
2036 .Dl \ \ \ \ smime-sign smime-sign-cert=+smime.pair
2041 contains complete example configurations.
2044 .\" .Ss "Command line editor" {{{
2045 .Ss "Command line editor"
2047 \*(OP \*(UA can be configured to support a command line editor and
2048 command history lists which are saved in between sessions.
2049 One may link against fully-fledged external libraries
2050 .Pf ( Xr readline 6 ,
2052 ) or use \*(UA's own command line editor NCL (Nail-Command-Line)
2053 instead, which should work in all environments which comply to the
2054 ISO C standard (ISO/IEC 9899:1990/Amendment 1:1995).
2055 When an external library is used, interactive behaviour of \*(UA relies
2056 on that library and may not correspond one-to-one to what is described
2060 Regardless of the actually used command line editor
2062 entries will be created for lines entered in command mode only, and
2063 creation of such an entry can be forcefully suppressed by starting the
2064 line with a space character.
2067 handling is by itself an optional feature and may therefore not be
2069 For more information see the documentation of the variables
2073 .Va history-gabby-persist ,
2076 .Va line-editor-disable .
2077 And there is also the \*(OPal
2079 will can be set to cause overall screen resets when \*(UA releases the
2080 terminal in interactive mode.
2083 The builtin \*(UA command line editor supports the following operations;
2086 stands for the combination of the
2088 key plus the mentioned character, e.g.,
2091 .Dq hold down control key and press the A key :
2094 .Bl -tag -compact -width "Ql _M"
2096 Go to the start of the line.
2098 Move the cursor backward one character.
2100 Forward delete the character under the cursor;
2101 quits \*(UA if used on the empty line unless the
2105 Go to the end of the line.
2107 Move the cursor forward one character.
2110 Cancel current operation, full reset.
2111 If there is an active history search or tabulator expansion then this
2112 command will first reset that, reverting to the former line content;
2113 thus a second reset is needed for a full reset in this case.
2114 In all cases \*(UA will reset a possibly used multibyte character input
2120 backward delete one character.
2124 .Dq horizontal tabulator :
2125 try to expand the word before the cursor.
2127 .Dq tabulator-completion
2128 as is known from the
2130 but really means the usual \*(UA expansion, as documented for
2132 yet it involves shell expansion as a last step, too.)
2137 complete this line of input.
2139 Delete all characters from the cursor to the end of the line.
2143 \*(OP Go to the next history entry.
2148 \*(OP Go to the previous history entry.
2150 \*(OP Complete the current line from (the remaining older) history entries.
2157 Delete the characters from the one preceding the cursor to the preceding
2160 Move the cursor forward one word boundary.
2162 Move the cursor backward one word boundary.
2166 If problems with commands that are based upon rightwise movement are
2167 encountered, adjustments of the option
2168 .Va line-editor-cursor-right
2169 may solve the problem, as documented for it.
2172 If the terminal produces key sequences which are compatible with
2174 then the left and right cursor keys will map to
2178 respectively, the up and down cursor keys will map to
2182 and the Home/End/PgUp/PgDown keys will call the
2184 command with the respective arguments
2190 (i.e., perform scrolling through the header summary list).
2193 .\" .Ss "Coloured message display" {{{
2194 .Ss "Coloured message display"
2196 \*(OP \*(UA can be configured to support coloured message display,
2197 realized by emitting ANSI colour escape sequences.
2198 Colours are only used when the
2200 environment variable is set and either the terminal type can be found in
2202 or its name includes the string
2206 On top of what \*(UA knows about the terminal the boolean variable
2208 defines wether these colour sequences are also generated when the output
2209 of a command needs to go through the
2213 ) \(en this is not enabled by default because different pager programs
2214 need different command line switches or other configuration in order to
2215 support those colour sequences, please see the option for more details.
2218 To forcefully disable all colour support, set
2219 .Va colour-disable .
2222 Colours can be configured through font attributes
2243 Multiple specifications can be joined in a comma separated list, as in
2246 .Dl set colour-msginfo="ft=bold,fg=magenta,bg=cyan"
2249 Variables to be set are
2250 .Va colour-msginfo ,
2251 .Va colour-partinfo ,
2255 .Va colour-uheader ,
2257 .Va colour-user-headers ,
2258 which is a list of headers to be colourized via
2260 instead of the default
2263 .\" }}} (DESCRIPTION)
2266 .\" .Sh COMMANDS {{{
2269 Each command is typed on a line by itself,
2270 and may take arguments following the command word.
2271 The command need not be typed in its entirety \(en
2272 the first command which matches the typed prefix is used.
2273 An \(en alphabetically \(en sorted list of commands can be shown
2280 when given an argument, will show a documentation string for the
2281 command matching the expanded argument, as in
2283 which should be a shorthand of
2285 documentation strings are however \*(OPal.
2288 For commands which take message lists as arguments, the next message
2289 forward that satisfies the command's requirements will be used shall no
2290 explicit message list have been specified.
2291 If there are no messages forward of the current message,
2292 the search proceeds backwards,
2293 and if there are no good messages at all,
2295 .Dq no applicable messages
2296 and aborts the command.
2297 The arguments to commands can be quoted, using the following methods:
2300 .Bl -bullet -compact -offset indent
2302 An argument can be enclosed between paired double-quotes
2307 any white space, shell word expansion, or backslash characters (except
2308 as described next) within the quotes are treated literally as part of
2310 A double-quote will be treated literally within single-quotes and vice
2312 Inside such a quoted string the actually used quote character can be
2313 used nonetheless by escaping it with a backslash
2319 An argument that is not enclosed in quotes, as above, can usually still
2320 contain space characters if those spaces are backslash-escaped, as in
2324 A backslash outside of the enclosing quotes is discarded
2325 and the following character is treated literally as part of the argument.
2328 An unquoted backslash at the end of a command line is discarded and the
2329 next line continues the command.
2333 Filenames, where expected, are subsequently subjected to the following
2334 transformations, in sequence:
2337 .Bl -bullet -compact -offset indent
2339 If the filename begins with an unquoted plus sign, and the
2341 variable is defined,
2342 the plus sign will be replaced by the value of the
2344 variable followed by a slash.
2347 variable is unset or is set to null, the filename will be unchanged.
2350 Shell word expansions are applied to the filename.
2351 .\" TODO shell word expansion shell expand fexpand FEXP_NSHELL
2352 .Sy Compatibility note:
2353 on the long run support for complete shell word expansion will be
2354 replaced by an internally implemented restricted expansion mechanism in
2355 order to circumvent possible security impacts through shell expansion.
2356 Expect that a growing number of program parts only support this
2359 Meta expansions are applied to the filename: leading tilde characters
2361 will be replaced by the expansion of
2363 and any occurrence of
2367 will be replaced by the expansion of the variable, if possible;
2368 \*(UA internal as well as environmental (shell) variables can be
2369 accessed through this mechanism.
2370 In order to include a raw
2372 character precede it with a backslash
2374 to include a backslash double it.
2375 If more than a single pathname results from this expansion and the
2376 command is expecting one file, an error results.
2378 Note that in interactive display context, in order to allow simple
2379 value acceptance (typing
2381 backslash quoting is performed automatically as necessary, e.g., a file
2382 .Ql diet\e is \ecurd.txt
2383 will be displayed as
2384 .Ql diet\e\e is \e\ecurd.txt .
2388 The following commands are available:
2390 .Bl -tag -width ".Ic _ccount"
2393 The comment-command causes the entire line to be ignored.
2395 this really is a normal command which' purpose is to discard its
2398 indicating special character, which means that, e.g., trailing comments
2399 on a line are not possible.
2403 Interprets the remainder of the word as a macro name and passes it
2408 is a shorter synonym for
2409 .Ql call Ar mymacro .
2413 Print out the preceding message.
2414 If given a numeric argument n,
2415 goes to the n'th previous message and prints it.
2419 Show the current message number (the
2424 Prints a brief summary of commands.
2425 \*(OP Given an argument a synopsis for the command in question is
2427 commands can be abbreviated in general and this command can be used
2428 to see the full expansion of an abbreviation including the synopsis,
2434 and see how the display changes.
2442 ) command which follows.
2452 (ac) Creates, selects or lists (an) account(s).
2453 An account is a group of commands and variable settings which together
2454 usually arrange the environment for the purpose of creating a system login.
2455 Without any argument a listing of all defined accounts and their content
2457 A specific account can be activated by giving solely its name, resulting
2458 in the system mailbox or inbox of that account to be activated as via an
2459 explicit use of the command
2461 The two argument form is identical to defining a macro as via
2464 .Bd -literal -offset indent
2466 set folder=imaps://mylogin@imap.myisp.example
2468 set from="myname@myisp.example (My Name)"
2469 set smtp=smtp://mylogin@smtp.myisp.example
2473 creates an account named
2475 which can later be selected by specifying
2479 (case-insensitive) always exists.
2481 can be used to localize account settings \(en different to normal macros
2482 the settings will be reverted once the account is switched off.
2483 Accounts can be deleted via
2488 (a) With no arguments, prints out all currently-defined aliases.
2489 With one argument, prints out that alias.
2490 With more than one argument,
2491 creates a new alias or appends to an existing one.
2493 can be used to delete aliases.
2497 (alt) Manage a list of alternate addresses / names of the active user,
2498 members of which will be removed from recipient lists when replying to
2501 variable is not set).
2502 If arguments are given the set of alternate names is replaced by them,
2503 without arguments the current set is displayed.
2507 Takes a message list and marks each message as having been answered.
2508 This mark has no technical meaning in the mail system;
2509 it just causes messages to be marked in the header summary,
2510 and makes them specially addressable.
2514 \*(OP\*(OB Only applicable to cached IMAP mailboxes;
2515 takes a message list and reads the specified messages into the IMAP
2520 Calls a macro that has been created via
2525 (ch) Change the working directory to
2527 or the given argument.
2533 \*(OP Only applicable to S/MIME signed messages.
2534 Takes a message list and a file name and saves the certificates
2535 contained within the message signatures to the named file in both
2536 human-readable and PEM format.
2537 The certificates can later be used to send encrypted messages to the
2538 respective message senders by setting
2539 .Va smime-encrypt-USER@HOST
2544 (ch) Change the working directory to
2546 or the given argument.
2552 Only applicable to threaded mode.
2553 Takes a message list and makes all replies to these messages invisible
2554 in header summaries, unless they are in state
2559 \*(OP\*(OB If operating in disconnected mode on an IMAP mailbox,
2560 switch to online mode and connect to the mail server while retaining
2562 See the description of the
2564 variable for more information.
2568 (C) Copy messages to files whose names are derived from the author of
2569 the respective message and don't mark them as being saved;
2570 otherwise identical to
2575 (c) Copy messages to the named file and don't mark them as being saved;
2576 otherwise identical to
2581 Print the current working directory.
2585 \*(OP For unencrypted messages this command is identical to
2587 Encrypted messages are first decrypted, if possible, and then copied.
2591 \*(OP For unencrypted messages this command is identical to
2593 Encrypted messages are first decrypted, if possible, and then copied.
2597 Without arguments the current list of macros, including their content,
2598 is printed, otherwise a macro is defined.
2599 A macro definition is a sequence of commands in the following form:
2600 .Bd -literal -offset indent
2609 A defined macro can be invoked explicitly by using the
2613 commands, or implicitly by setting the
2616 .Va folder-hook-FOLDER
2618 Note that interpretation of
2620 depends on how (i.e.,
2622 normal macro, folder hook, account switch) the macro is invoked.
2623 Macros can be deleted via
2625 .Bd -filled -compact -offset indent
2627 Macro behaviour, including option localization, will change in v15.
2628 To be on the absolutely safe side and avoid any surprises it may be wise
2629 to use wrappers that depend on the program version, e.g.,:
2631 .Bd -literal -offset indent
2632 if $version-major < 15
2638 echo "Please reverify macro name (post v15)"
2645 (d) Marks the given message list as
2647 Deleted messages will neither be saved in
2649 nor will they be available for most other commands.
2660 \*(OP\*(OB (disco) If operating in online mode on an IMAP mailbox,
2661 switch to disconnected mode while retaining the mailbox status.
2662 See the description of the
2665 A list of messages may optionally be given as argument;
2666 the respective messages are then read into the cache before the
2667 connection is closed.
2668 Thus `disco *' makes the entire mailbox available for disconnected use.
2673 Deletes the current message and prints the next message.
2674 If there is no next message, \*(UA says
2679 Takes a message list and marks each given message as a draft.
2680 This mark has no technical meaning in the mail system;
2681 it just causes messages to be marked in the header summary,
2682 and makes them specially addressable.
2686 (ec) Echoes its arguments,
2687 resolving special names as documented for the command
2689 The escape sequences
2701 are interpreted just as they are by
2703 (proper quoting provided).
2707 (e) Point the text editor (as defined in
2709 at each message from the given list in turn.
2710 Modified contents are discarded unless the
2717 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
2718 conditional \(em if the condition of a preceeding
2720 was false, check the following condition and execute the following block
2721 if it evaluates true.
2726 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
2727 conditional \(em if none of the conditions of the preceeding
2731 commands was true, the
2737 (en) Marks the end of an
2738 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
2739 conditional execution block.
2743 \*(OP Since \*(UA uses the console as a user interface it can happen
2744 that messages scroll by too fast to become recognized.
2745 Optionally an error message ring queue is available which stores
2746 duplicates of any error message and notifies the user in interactive
2747 sessions whenever a new error has occurred.
2748 The queue is finite: if its maximum size is reached any new message
2749 replaces the eldest.
2752 can be used to manage this message queue: if given
2754 or no argument the queue will be displayed and cleared,
2756 will only clear all messages from the queue.
2760 (ex or x) Exit from \*(UA without changing the active mailbox and skip
2761 any saving of messages in
2763 as well as a possibly tracked command line editor history file.
2767 Show the list of features that have been compiled into \*(UA.
2768 (Outputs the contents of the variable
2775 but open the mailbox readonly.
2779 (fi) The file command switches to a new mailbox.
2780 Without arguments it prints the complete state of the current mailbox.
2781 If an argument is given, it will write out changes (such as deletions)
2782 the user has made and open a new mailbox.
2783 Some special conventions are recognized for the
2787 .Bl -tag -compact -offset indent -width ".Ar %:__lespec"
2789 (number sign) means the previous file,
2791 (percent sign) means the invoking user's system mailbox
2796 means the system mailbox of
2798 (and never the value of
2800 regardless of its actual setting),
2802 (ampersand) means the invoking user's
2812 expands to the same value as
2814 but the file is handled as a system mailbox by, e.g., the
2818 commands, meaning that messages that have been read in the current
2819 session will be moved to the
2821 mailbox instead of simply being flagged as read.
2824 If the name matches one of the strings defined with the command
2826 it is replaced by its long form and expanded.
2827 If the name ends with
2832 it is treated as being compressed with
2837 respectively, and transparently handled through an intermediate
2838 (un)compression step (using a temporary file) with the according
2839 facility, sufficient support provided.
2840 Likewise, if the named file doesn't exist, but a file with one of the
2841 mentioned compression extensions does, then the name is automatically
2842 expanded and the compressed file is used.
2844 Otherwise, if the name ends with an extension for which
2845 .Va file-hook-load-EXTENSION
2847 .Va file-hook-save-EXTENSION
2848 variables are set, then the given hooks will be used to load and save
2850 and \*(UA will work with an intermediate temporary file.
2852 MBOX files (flat file-based mailboxes) are generally locked during file
2853 operations in order to avoid inconsistencies due to concurrent
2855 \*(OPal Mailbox files which \*(UA treats as system or primary mailboxes
2856 will also be protected by so-called dotlock files, the traditional way
2857 of mail spool file locking: for any file
2861 will be created for the duration of the synchronization \(em
2862 as necessary a privilege-separated dotlock child process will be used
2863 to accommodate for necessary privilege adjustments in order to create
2864 the dotlock file in the same directory
2865 and with the same user and group identities as the file of interest.
2868 for fine-tuning the handling of MBOX files.
2872 refers to a directory with the subdirectories
2877 then it is treated as a folder in
2882 .Dl \*(IN protocol://[user[:password]@]host[:port][/path]
2883 .Dl \*(OU protocol://[user@]host[:port][/path]
2885 is taken as an Internet mailbox specification.
2886 The \*(OPally supported protocols are
2890 (POP3 with SSL/TLS encrypted transport).
2893 part is valid only for IMAP; there it defaults to
2895 Also see the section
2896 .Sx "On URL syntax and credential lookup" .
2900 contains special characters, in particular
2904 they must be escaped in URL notation \(en the command
2906 can be used to show the necessary conversion.
2907 The optional `path' part applies to IMAP only;
2908 if it is omitted, the default `INBOX' is used.
2910 If \*(UA is connected to an IMAP server,
2911 a name of the form `@mailbox' refers to the `mailbox' on that server,
2912 but otherwise a `@' prefix has no special meaning.
2916 Takes a message list and marks the messages as
2918 ged for urgent/special attention.
2919 This mark has no technical meaning in the mail system;
2920 it just causes messages to be highlighted in the header summary,
2921 and makes them specially addressable.
2930 With no arguments, list the names of the folders in the folder directory.
2931 With an existing folder as an argument,
2932 lists the names of folders below the named folder;
2933 e.\|g. the command `folders @' lists the folders on the base level of
2934 the current IMAP server.
2935 See also the variable
2936 .Va imap-list-depth .
2942 but saves the message in a file named after the local part of the first
2943 recipient's address (instead of in
2950 but saves the message in a file named after the local part of the first
2951 recipient's address (instead of in
2958 but responds to all recipients regardless of the
2963 .It Ic followupsender
2966 but responds to the sender only regardless of the
2982 (f) Takes a list of messages and prints their message headers
2983 (which qualifies this command as \*(UAs search facility).
2989 but saves the message in a file named after the local part of the
2990 recipient's address (instead of in
2995 Takes a message and the address of a recipient
2996 and forwards the message to him.
2997 The text of the original message is included in the new one,
2998 with the value of the
3000 variable printed before.
3005 commands specify which header fields are included in the new message.
3006 Only the first part of a multipart message is included unless the
3007 .Va forward-as-attachment
3011 is set recipient addresses will be stripped from comments, names etc.
3015 Specifies which header fields are to be ignored with the command
3017 This command has no effect when the
3018 .Va forward-as-attachment
3023 Specifies which header fields are to be retained with the command
3028 This command has no effect when the
3029 .Va forward-as-attachment
3034 Define or list command aliases, so-called ghosts.
3035 Without arguments a list of all currently known aliases is printed.
3036 With one argument the expansion of the given alias is shown.
3037 With two or more arguments a command alias is defined or updated: the
3038 first argument is the name under which the remaining command line should
3039 be accessible, the content of which can be just about anything.
3040 A ghost can be used everywhere a normal command can be used, but always
3041 takes precedence; any arguments that are given to the command alias are
3042 joined onto the alias content, and the resulting string forms the
3043 command line that is, in effect, executed.
3046 .Bd -literal -offset indent
3048 `ghost': no such alias: "xx"
3051 ghost xx "echo hello,"
3060 (h) Show the current group of headers, the size of which depends on
3063 If a message-specification is given the group of headers containing the
3064 first message therein is shown and the message at the top of the screen
3079 the list of history entries;
3082 argument selects and shows the respective history entry \(en
3085 to accept it, and the history entry will become the new history top.
3086 The default mode if no arguments are given is
3093 Takes a message list and marks each message therein to be saved in the
3094 user's system mailbox instead of in
3096 Does not override the
3099 \*(UA deviates from the POSIX standard with this command, because a
3101 command issued after
3103 will display the following message, not the current one.
3108 (i) Part of the nestable
3109 .Ic if Ns / Ns Ic elif Ns / Ns Ic else Ns / Ns Ic endif
3110 conditional execution construct \(em if the given condition is true then
3111 the encapsulated block is executed.
3112 POSIX only supports the (case-insensitive) conditions
3117 end, all remaining conditions are non-portable extensions; note that
3118 falsely specified conditions cause the execution of the entire
3119 conditional construct until the (matching) closing
3121 command to be suppressed.
3122 The syntax of the nestable
3124 conditional execution construct requires that each condition and syntax
3125 element is surrounded by whitespace.
3127 .Bd -literal -offset indent
3136 The (case-insensitive) condition
3138 erminal will evaluate to true if the standard input is a terminal, i.e.,
3139 in interactive sessions.
3140 Another condition can be any boolean value (see the section
3141 .Sx "INTERNAL VARIABLES"
3142 for textual boolean representations) to mark an enwrapped block as
3145 .Dq always execute .
3146 It is possible to check a variable for existence or compare its
3147 expansion against a user given value or another variable via the
3149 .Pf ( Dq variable next )
3150 conditional trigger character.
3151 The available comparison operators are
3155 (less than or equal to),
3161 (greater than or equal to),
3165 (is substring of) and
3167 (is not substring of).
3168 The values of the left and right hand side are treated as strings and
3169 are compared 8-bit byte-wise, ignoring case according to the rules of
3170 the US-ASCII encoding (therefore, dependend on the active locale,
3171 possibly producing false results for strings in the locale encoding).
3172 Except for the substring checks the comparison will instead be performed
3173 arithmetically if both, the user given value as well as the variable
3174 content, can be parsed as numbers (integers).
3175 An unset variable is treated as the empty string.
3178 When the \*(OPal regular expression support is available, the additional
3184 They treat the right hand side as an extended regular expression that is
3185 matched case-insensitively and according to the active
3187 locale, meaning that strings in the locale encoding should be matched
3191 Conditions can be joined via AND-OR lists (where the AND operator is
3193 and the OR operator is
3195 which have equal precedence and will be evaluated with left
3196 associativity, thus using the same syntax that is known for the
3198 It is also possible to form groups of conditions and lists by enclosing
3199 them in pairs of brackets
3200 .Ql [\ \&.\&.\&.\ ] ,
3201 which may be interlocked within each other, and also be joined via
3205 The results of individual conditions and entire groups may be modified
3206 via unary operators: the unary operator
3208 will reverse the result.
3210 .Bd -literal -offset indent
3214 if $ttycharset == "UTF-8"
3215 echo *ttycharset* is set to UTF-8, case-insensitively
3219 echo These two variables are equal
3221 if $version-major >= 15
3222 echo Running a new version..
3223 if $features =@ "regex"
3224 if $TERM =~ "^xterm\&.*"
3225 echo ..in an X terminal
3228 if [ [ true ] && [ [ $debug ] || [ $verbose ] ] ]
3231 if true && $debug || $verbose
3232 echo Left associativity, as is known from the shell
3234 if ! ! true && ! [ ! $debug && ! $verbose ]
3235 echo Unary operator support
3243 Without arguments the list of ignored header fields is printed,
3244 otherwise the given list of header fields is added to the ignore list:
3245 Header fields in the ignore list are not printed on the terminal when
3246 a message is printed.
3247 To print a message in its entirety, use the commands
3258 \*(OP\*(OB Sends command strings directly to the current IMAP server.
3259 \*(UA operates always in IMAP `selected state' on the current mailbox;
3260 commands that change this will produce undesirable results and should be
3262 Useful IMAP commands are:
3263 .Bl -tag -offset indent -width ".Ic getquotearoot"
3265 Takes the name of an IMAP mailbox as an argument and creates it.
3267 (RFC 2087) Takes the name of an IMAP mailbox as an argument
3268 and prints the quotas that apply to the mailbox.
3269 Not all IMAP servers support this command.
3271 (RFC 2342) Takes no arguments and prints the Personal Namespaces,
3272 the Other User's Namespaces and the Shared Namespaces.
3273 Each namespace type is printed in parentheses;
3274 if there are multiple namespaces of the same type,
3275 inner parentheses separate them.
3276 For each namespace a prefix and a hierarchy separator is listed.
3277 Not all IMAP servers support this command.
3287 Prints the names of all available commands, alphabetically sorted.
3291 This command can be used to localize changes to variables, meaning that
3292 their state will be reverted to the former one once the covered scope
3294 It can only be used inside of macro definition blocks introduced by
3298 and is interpreted as a boolean (string, see
3299 .Sx "INTERNAL VARIABLES" ) ;
3302 of an account is left once it is switched off again.
3303 .Bd -literal -offset indent
3304 define temporary_settings {
3319 enables change localization and calls
3321 which explicitly resets localization, then any value changes within
3323 will still be reverted by
3328 Reply to messages that come in via known
3331 .Pf ( Ic mlsubscribe )
3332 mailing lists, or pretend to do so (see
3333 .Sx "Mailing lists" ) :
3336 functionality this will actively resort and even remove message
3337 recipients in order to generate a message that is supposed to be send to
3339 For example it will also implicitly generate a
3340 .Ql Mail-Followup-To:
3341 header if that seems useful, regardless of the setting of the variable
3348 but saves the message in a file named after the local part of the first
3349 recipient's address (instead of in
3354 (m) Takes a (list of) recipient address(es) as (an) argument(s),
3355 or asks on standard input if none were given;
3356 then collects the remaining mail content and sends it out.
3360 (mb) The given message list is to be sent to
3362 when \*(UA is quit; this is the default action unless the
3365 \*(ID This command can only be used in a system mailbox (see
3370 Without any arguments the content of the MIME type cache will displayed.
3371 Otherwise each argument defines a complete MIME type specification of
3372 a type that shall be added (prepended) to the cache.
3373 In any event MIME type sources are loaded first as necessary \(en
3374 .Va mimetypes-load-control
3375 can be used to fine-tune which sources are actually loaded.
3376 Refer to the section on
3377 .Sx "The mime.types files"
3378 for more on MIME type specifications and this topic in general.
3379 MIME type unregistration and cache resets can be triggered with
3384 Without arguments the list of all currently defined mailing lists
3385 (and their attributes, if any) is printed.
3386 Otherwise all given arguments (which need not be quoted except for
3387 whitespace) will be added and henceforth be recognized as mailing lists.
3388 Mailing lists may be removed via the command
3391 If the \*(OPal regular expression support is available then mailing
3392 lists may also be specified as (extended) regular expressions (see
3398 Without arguments the list of all currently defined mailing lists which
3399 have a subscription attribute is printed.
3400 Otherwise this attribute will be set for all given mailing lists,
3401 newly creating them as necessary (as via
3403 Subscription attributes may be removed via the command
3412 but moves the messages to a file named after the local part of the
3413 sender address of the first message (instead of in
3420 but marks the messages for deletion if they were transferred
3427 but also prints ignored header fields and all MIME parts.
3435 on the given messages, even in non-interactive mode and as long as the
3436 standard output is a terminal.
3448 cache, loading the file first as necessary in the former case.
3449 Note that \*(UA will try to read the file only once, use
3450 .Ql Ic netrc Ns \:\0\:clear
3451 to unlock the next attempt.
3455 .Sx "On URL syntax and credential lookup" ;
3457 .Sx "The .netrc file"
3458 documents the file format in detail.
3462 Checks for new mail in the current folder without committing any changes
3464 If new mail is present, a message is printed.
3468 the headers of each new message are also printed.
3476 Goes to the next message in sequence and types it.
3477 With an argument list, types the next matching message.
3491 If the current folder is accessed via a network connection, a
3493 command is sent, otherwise no operation is performed.
3499 but also prints ignored header fields and all MIME parts.
3507 on the given messages, even in non-interactive mode and as long as the
3508 standard output is a terminal.
3516 but also pipes ignored header fields and all parts of MIME
3517 .Ql multipart/alternative
3522 (pi) Takes a message list and a shell command
3523 and pipes the messages through the command.
3524 Without an argument the current message is piped through the command
3531 every message is followed by a formfeed character.
3552 (q) Terminates the session, saving all undeleted, unsaved messages in
3555 preserving all messages marked with
3559 or never referenced in the system mailbox,
3560 and removing all other messages from the system mailbox.
3561 If new mail has arrived during the session,
3563 .Dq You have new mail
3565 If given while editing a mailbox file with the command line flag
3567 then the edit file is rewritten.
3568 A return to the shell is effected,
3569 unless the rewrite of edit file fails,
3570 in which case the user can escape with the exit command.
3584 Removes the named folders.
3585 The user is asked for confirmation in interactive mode.
3589 Takes the name of an existing folder
3590 and the name for the new folder
3591 and renames the first to the second one.
3592 Both folders must be of the same type
3593 and must be located on the current server for IMAP.
3597 (R) Reply to originator.
3598 Does not reply to other recipients of the original message.
3600 will exchange this command with
3604 is set the recipient address will be stripped from comments, names etc.
3608 (r) Take a message and group-responds to it by addressing the sender
3611 .Va followup-to-honour ,
3614 .Va recipients-in-cc
3615 influence response behaviour.
3618 offers special support for replying to mailing lists.
3621 is set recipient addresses will be stripped from comments, names etc.
3634 but initiates a group-reply regardless of the value of
3641 but responds to the sender only regardless of the value of
3648 but does not add any header lines.
3649 This is not a way to hide the sender's identity,
3650 but useful for sending a message again to the same recipients.
3654 Takes a list of messages and a user name
3655 and sends each message to the named user.
3657 and related header fields are prepended to the new copy of the message.
3675 .It Ic respondsender
3681 (ret) Without arguments the list of retained header fields is printed,
3682 otherwise the given list of header fields is added to the retain list:
3683 Header fields in the retain list are shown on the terminal when
3684 a message is printed, all other header fields are suppressed.
3685 To print a message in its entirety, use the commands
3694 takes precedence over the mentioned.
3700 but saves the messages in a file named after the local part of the
3701 sender of the first message instead of (in
3703 and) taking a filename argument.
3707 (s) Takes a message list and a filename and appends each message in turn
3708 to the end of the file.
3709 If no filename is given, the
3712 The filename in quotes, followed by the generated character count
3713 is echoed on the user's terminal.
3714 If editing a system mailbox the messages are marked for deletion.
3715 Filename interpretation as described for the
3717 command is performed.
3734 Header fields thus marked are filtered out when saving a message by
3736 or when automatically saving to
3738 This command should only be applied to header fields that do not contain
3739 information needed to decode the message,
3740 as MIME content fields do.
3741 If saving messages on an IMAP account ignoring fields makes it
3742 impossible to copy the data directly on the server,
3743 thus operation usually becomes much slower.
3755 Header fields thus marked are the only ones saved with a message when
3758 or when automatically saving to
3763 The use of this command is strongly discouraged since it may strip
3764 header fields that are needed to decode the message correctly.
3768 Takes a message list and marks all messages as having been read.
3772 (se) Without arguments this command prints all variables and their
3773 values which are currently known to \*(UA.
3774 Setting any of the variables
3778 changes the output format to BSD style, otherwise a properly quoted
3779 listing is produced.
3784 has been set twice then the listing is modified to mark out assembled
3787 Otherwise modifies (set and unsets) the given variables.
3788 Arguments are of the form
3790 (no space before or after
3794 if there is no value.
3795 Quotation marks may be placed around any part of the assignment
3796 statement to quote blanks or tabs, e.g.,
3798 .Dl set indentprefix="->"
3800 If an argument begins with
3804 the effect is the same as invoking the
3806 command with the remaining part of the variable
3807 .Pf ( Ql unset save ) .
3813 except that the variables are also exported into the program environment;
3814 since this task requires native host support the command will always
3815 report error if that is not available (but still act like
3818 This operation is a no-op unless all resource files have been loaded.
3824 (sh) Invokes an interactive version of the shell.
3828 Without arguments the list of all currently defined shortcuts is
3830 Otherwise all given arguments (which need not be quoted except for
3831 whitespace) are treated as pairs of shortcuts and their expansions,
3832 creating new or changing already existing shortcuts, as necessary.
3833 Shortcuts may be removed via the command
3835 The expansion strings should be in the syntax that has been described
3844 but performs neither MIME decoding nor decryption, so that the raw
3845 message text is shown.
3849 (si) Print the size in characters of each message of the given
3854 Shows the current sorting criterion when used without an argument.
3855 Otherwise creates a sorted representation of the current folder,
3858 command and the addressing modes such that they refer to messages in
3860 Message numbers are the same as in regular mode.
3864 a header summary in the new order is also displayed.
3865 Automatic folder sorting can be enabled by setting the
3867 variable, as in, e.g.,
3868 .Ql set autosort=thread .
3869 Possible sorting criterions are:
3871 .Bl -tag -compact -offset indent -width "subject"
3873 Sort the messages by their
3875 field, that is by the time they were sent.
3877 Sort messages by the value of their
3879 field, that is by the address of the sender.
3882 variable is set, the sender's real name (if any) is used.
3884 Sort the messages by their size.
3886 \*(OP Sort the message by their spam score, as has been classified by
3889 Sort the messages by their message status.
3891 Sort the messages by their subject.
3893 Create a threaded display.
3895 Sort messages by the value of their
3897 field, that is by the address of the recipient.
3900 variable is set, the recipient's real name (if any) is used.
3905 (so) The source command reads commands from a file.
3911 is that this command will not generate an error if the given file
3912 argument cannot be opened successfully.
3913 This can matter in, e.g., resource files, since loading of those is
3914 stopped when an error is encountered.
3918 \*(OP Takes a list of messages and clears their
3924 \*(OP Takes a list of messages and causes the
3926 to forget it has ever used them to train its Bayesian filter.
3927 Unless otherwise noted the
3929 flag of the message is inspected to chose wether a message shall be
3937 \*(OP Takes a list of messages and informs the Bayesian filter of the
3941 This also clears the
3943 flag of the messages in question.
3947 \*(OP Takes a list of messages and rates them using the configured
3948 .Va spam-interface ,
3949 without modifying the messages, but setting their
3951 flag as appropriate; because the spam rating headers are lost the rate
3952 will be forgotten once the mailbox is left.
3953 Refer to the manual section
3955 for the complete picture of spam handling in \*(UA.
3959 \*(OP Takes a list of messages and sets their
3965 \*(OP Takes a list of messages and informs the Bayesian filter of the
3971 flag of the messages in question.
3980 Create a threaded representation of the current folder,
3981 i.\|e. indent messages that are replies to other messages in the header
3982 display and change the
3984 command and the addressing modes such that they refer to messages in the
3986 Message numbers are the same as in unthreaded mode.
3990 a header summary in threaded order is also printed.
3994 (to) Takes a message list and prints the top few lines of each.
3995 The number of lines printed is controlled by the variable
3997 and defaults to five.
4001 (tou) Takes a message list and marks the messages for saving in
4003 \*(UA deviates from the POSIX standard with this command,
4006 command will display the following message instead of the current one.
4012 but also prints out ignored header fields and all parts of MIME
4013 .Ql multipart/alternative
4018 (t) Takes a message list and types out each message on the user's
4024 For MIME multipart messages, all parts with a content type of
4028 are shown, the other are hidden except for their headers.
4029 Messages are decrypted and converted to the terminal character set
4034 Delete all given accounts.
4035 An error message is printed if a given account is not defined.
4038 will discard all existing accounts.
4042 (una) Takes a list of names defined by alias commands
4043 and discards the remembered groups of users.
4046 will discard all existing aliases.
4050 Takes a message list and marks each message as not having been answered.
4054 Only applicable to threaded mode.
4055 Takes a message list and makes the message and all replies to it visible
4056 in header summaries again.
4057 When a message becomes the current message,
4058 it is automatically made visible.
4059 Also when a message with collapsed replies is printed,
4060 all of these are automatically uncollapsed.
4064 Undefine all given macros.
4065 An error message is printed if a given macro is not defined.
4068 will discard all existing macros.
4072 (u) Takes a message list and marks each message as not being deleted.
4076 Takes a message list and
4082 Takes a message list and marks each message as not being
4087 Removes the header field names from the list of ignored fields for the
4092 will remove all fields.
4096 Removes the header field names from the list of retained fields for the
4101 will remove all fields.
4105 Remove all the given command
4109 will remove all ghosts.
4113 Removes the header field names from the list of ignored fields.
4116 will remove all fields.
4120 Delete all given MIME types, e.g.,
4121 .Ql unmimetype text/plain
4122 will remove all registered specifications for the MIME type
4126 will discard all existing MIME types, just as will
4128 but which also reenables cache initialization via
4129 .Va mimetypes-load-control .
4133 Forget about all the given mailing lists.
4136 will remove all lists.
4141 .It Ic unmlsubscribe
4142 Remove the subscription attribute from all given mailing lists.
4145 will clear the attribute from all lists which have it set.
4156 Takes a message list and marks each message as not having been read.
4160 Removes the header field names from the list of retained fields.
4163 will remove all fields.
4167 Removes the header field names from the list of ignored fields for
4171 will remove all fields.
4175 Removes the header field names from the list of retained fields for
4179 will remove all fields.
4183 (uns) Takes a list of option names and discards their remembered values;
4191 except that the variables are also removed from the program environment;
4192 since this task requires native host support the command will always
4193 report error if that is not available (but still act like
4196 This operation is a no-op unless all resource files have been loaded.
4202 Deletes the shortcut names given as arguments.
4205 will remove all shortcuts.
4209 Disable sorted or threaded mode
4215 return to normal message order and,
4219 print a header summary.
4229 Decode the given URL-encoded string arguments and show the results.
4230 Note the resulting strings may not be valid in the current locale, see
4235 URL-encode the given arguments and show the results.
4236 Because the arguments effectively are in the character set of the
4237 current locale the results will vary accordingly unless the input solely
4238 consists of characters in the portable character set, see
4239 .Sx "Character sets" .
4243 Edit the values of or create the given variable(s) in the
4245 Boolean variables cannot be edited.
4249 Show informations about all the given variables.
4250 \*(UA knows about a finite set of known builtin variables that are
4251 subdivided further in boolean and value variants;
4252 they may have special properties, like
4254 (setting may not be changed) and
4256 meaning that the value is generated on-the-fly as necessary.
4257 Beside those known variables an infinite number of unknown, so-called
4259 variables, which are expected to be able to store values, may exist.
4260 .Bd -literal -offset indent
4262 ? varshow sendwait version-major foo bar
4263 "sendwait": (73) boolean: set=1 (ENVIRON=0)
4264 "version-major": (192) value, read-only, virtual:\e
4265 set=1 (ENVIRON=0) value<14>
4266 "foo": (assembled) set=1 (ENVIRON=0) value<bar>
4267 "bar": (assembled) set=0 (ENVIRON=0) value<NULL>
4272 \*(OP Takes a message list and verifies each message.
4273 If a message is not a S/MIME signed message,
4274 verification will fail for it.
4275 The verification process checks if the message was signed using a valid
4277 if the message sender's email address matches one of those contained
4278 within the certificate,
4279 and if the message content has been altered.
4283 (v) Takes a message list and invokes the display editor on each message.
4284 Modified contents are discarded unless the
4290 (w) For conventional messages the body without all headers is written.
4291 The output is decrypted and converted to its native format as necessary.
4292 If the output file exists, the text is appended.
4293 If a message is in MIME multipart format its first part is written to
4294 the specified file as for conventional messages,
4295 and the user is asked for a filename to save each other part.
4296 For convience saving of each part may be skipped by giving an empty value;
4297 the same result can also be achieved by writing it to
4299 For the second and subsequent parts a leading
4301 character causes the part to be piped to the remainder of the user input
4302 interpreted as a shell command;
4303 otherwise the user input is expanded as usually for folders,
4304 e.g., tilde expansion is performed.
4305 In non-interactive mode, only the parts of the multipart message
4306 that have a filename given in the part header are written,
4307 the others are discarded.
4308 The original message is never marked for deletion in the originating
4311 the contents of the destination file are overwritten if the file
4313 No special handling of compressed files is performed.
4322 \*(UA presents message headers in windowfuls as described under the
4325 This command scrolls to the next window of messages.
4326 If an argument is given,
4327 it specifies the window to use.
4328 A number prefixed by
4332 indicates that the window is calculated in relation to the current position.
4333 A number without a prefix specifies an absolute window number,
4336 lets \*(UA scroll to the last window of messages.
4342 but scrolls to the next or previous window that contains at least one
4351 .\" .Sh TILDE ESCAPES {{{
4354 Here is a summary of the tilde escapes,
4355 which are used to perform special functions when composing messages.
4356 Tilde escapes are only recognized at the beginning of lines.
4359 is somewhat of a misnomer since the actual escape character can be
4360 changed by adjusting the option
4363 .Bl -tag -width ".Ic __ filename"
4366 Insert the string of text in the message prefaced by a single
4368 (If the escape character has been changed,
4369 that character must be doubled
4370 in order to send it at the beginning of a line.)
4373 .It Ic ~! Ar command
4374 Execute the indicated shell
4376 then return to the message.
4380 Same effect as typing the end-of-file character.
4383 .It Ic ~: Ar \*(UA-command Ns \0or Ic ~_ Ar \*(UA-command
4384 Execute the given \*(UA command.
4385 Not all commands, however, are allowed.
4389 Write a summary of command escapes.
4392 .It Ic ~< Ar filename
4397 .It Ic ~<! Ar command
4399 is executed using the shell.
4400 Its standard output is inserted into the message.
4403 .It Ic ~@ Op Ar filename...
4404 With no arguments, edit the attachment list interactively.
4405 If an attachment's file name is left empty,
4406 that attachment is deleted from the list.
4407 When the end of the attachment list is reached,
4408 \*(UA will ask for further attachments until an empty name is given.
4409 If a given file name solely consists of the number sign
4411 followed by a valid message number of the currently active mailbox, then
4412 the given message is attached as a MIME
4414 and the rest of this section does not apply.
4416 If character set conversion has been compiled into \*(UA, then this mode
4417 gives the user the option to specify input and output character sets,
4418 unless the file extension indicates binary content, in which case \*(UA
4419 asks wether this step shall be skipped for the attachment in question.
4420 If not skipped, then the charset that succeeds to represent the
4421 attachment data will be used in the
4423 MIME parameter of the mail message:
4425 .Bl -bullet -compact
4427 If input and output character sets are specified, then the conversion is
4428 performed on the fly.
4429 The user will be asked repeatedly until the desired conversion succeeds.
4431 If only an output character set is specified, then the input is assumed
4434 charset and will be converted to the given output charset on the fly.
4435 The user will be asked repeatedly until the desired conversion succeeds.
4437 If no character sets are specified at all then the algorithm that is
4438 documented in the section
4439 .Sx "Character sets"
4440 is applied, but directly and on the fly.
4441 The user will be asked repeatedly until the desired conversion succeeds.
4443 Finally, if an input-, but no output character set is specified, then no
4444 conversion is ever performed, but the
4446 MIME parameter value will still be set to the user input.
4448 The character set selection loop can be left by typing
4450 i.e., causing an interrupt.
4451 .\" \*(OU next sentence
4452 Note that before \*(UA version 15.0 this terminates the entire
4453 current attachment selection, not only the character set selection.
4456 Without character set conversion support, \*(UA will ask for the input
4457 character set only, and it'll set the
4459 MIME parameter value to the given input, if any;
4460 if no user input is seen then the
4462 character set will be used for the parameter value instead.
4463 Note that the file extension check isn't performed in this mode, since
4464 no conversion will take place anyway.
4466 Note that in non-interactive mode, for reproduceabilities sake, there
4467 will always be two questions for each attachment, regardless of wether
4468 character set conversion is available and what the file extension is.
4469 The first asks for the filename, and the second asks for the input
4470 character set to be passed through to the corresponding MIME parameter;
4471 no conversion will be tried if there is input to the latter question,
4472 otherwise the usual conversion algorithm, as above, is applied.
4473 For message attachments, the answer to the second question is completely
4478 arguments are specified for the
4480 command they are treated as a comma separated list of files,
4481 which are all expanded and appended to the end of the attachment list.
4482 (Filenames with commas, or with leading or trailing whitespace can only
4483 be added via the command line or the first method.
4484 Message attachments can only be added via the first method;
4485 filenames which clash with message numbers can only be added via the
4486 command line or the second method.)
4487 In this mode the (text) attachments are assumed to be in
4489 encoding, and will be evaluated as documented in the section
4490 .Sx "Character sets" .
4494 Inserts the string contained in the
4497 .Ql Ic ~i Ns \0Sign ) .
4498 The escape sequences tabulator
4506 Inserts the string contained in the
4509 .Ql Ic ~i Ns \0sign ) .
4510 The escape sequences tabulator
4517 .It Ic ~b Ar name ...
4518 Add the given names to the list of blind carbon copy recipients.
4521 .It Ic ~c Ar name ...
4522 Add the given names to the list of carbon copy recipients.
4526 Read the file specified by the
4528 variable into the message.
4532 Invoke the text editor on the message collected so far.
4533 After the editing session is finished,
4534 the user may continue appending text to the message.
4537 .It Ic ~F Ar messages
4538 Read the named messages into the message being sent, including all
4539 message headers and MIME parts.
4540 If no messages are specified, read in the current message.
4543 .It Ic ~f Ar messages
4544 Read the named messages into the message being sent.
4545 If no messages are specified, read in the current message.
4549 lists are used to modify the message headers.
4550 For MIME multipart messages,
4551 only the first printable part is included.
4555 Edit the message header fields
4561 by typing each one in turn and allowing the user to edit the field.
4562 The default values for these fields originate from the
4563 .Va from , replyto , sender
4570 Edit the message header fields
4576 by typing each one in turn and allowing the user to edit the field.
4579 .It Ic ~i Ar variable
4580 Insert the value of the specified variable into the message,
4581 adding a newline character at the end.
4582 The message remains unaltered if the variable is unset or empty.
4583 The escape sequences tabulator
4590 .It Ic ~M Ar messages
4591 Read the named messages into the message being sent,
4594 If no messages are specified, read the current message.
4597 .It Ic ~m Ar messages
4598 Read the named messages into the message being sent,
4601 If no messages are specified, read the current message.
4605 lists are used to modify the message headers.
4606 For MIME multipart messages,
4607 only the first printable part is included.
4611 Print out the message collected so far,
4612 prefaced by the message header fields
4613 and followed by the attachment list, if any.
4617 Abort the message being sent,
4618 copying it to the file specified by the
4625 .It Ic ~R Ar filename
4626 Read the named file into the message, indented by
4630 .It Ic ~r Ar filename
4631 Read the named file into the message.
4635 Cause the named string to become the current subject field.
4638 .It Ic ~t Ar name ...
4639 Add the given name(s) to the direct recipient list.
4642 .It Ic ~U Ar messages
4643 Read in the given / current message(s) excluding all headers, indented by
4647 .It Ic ~u Ar messages
4648 Read in the given / current message(s), excluding all headers.
4652 Invoke an alternate editor (defined by the
4654 option) on the message collected so far.
4655 Usually, the alternate editor will be a screen editor.
4656 After the editor is quit,
4657 the user may resume appending text to the end of the message.
4660 .It Ic ~w Ar filename
4661 Write the message onto the named file.
4663 the message is appended to it.
4669 except that the message is not saved at all.
4672 .It Ic ~| Ar command
4673 Pipe the message through the specified filter command.
4674 If the command gives no output or terminates abnormally,
4675 retain the original text of the message.
4678 is often used as a rejustifying filter.
4683 .\" .Sh INTERNAL VARIABLES {{{
4684 .Sh "INTERNAL VARIABLES"
4686 Internal \*(UA variables are controlled via the
4690 commands; prefixing a variable name with the string
4694 has the same effect as using
4700 Creation or editing of variables can be performed in the
4705 will give more insight on the given variable(s), and
4707 when called without arguments, will print a listing of all variables.
4708 Variables are also implicitly inherited from the program
4710 and can be set explicitly via the command line option
4714 Two different kind of variables exist.
4715 There are boolean variables, which can only be in one of the two states
4719 and value variables with a(n optional) string value.
4720 For the latter proper quoting is necessary upon assignment time:
4721 To embed whitespace (space and tabulator) in a value it either needs to
4722 be escaped with a backslash character, or the entire value must be
4723 enclosed in (double or single) quotation marks;
4724 To use quotation marks identical to those used to enclose the value,
4725 escape them with a backslash character.
4726 The backslash character has no special meaning except in these cases.
4728 .Bd -literal -offset indent
4729 set one=val\e 1 two="val 2" \e
4730 three='val "3"' four='val \e'4\e''
4731 varshow one two three four
4732 unset one two three four
4736 Dependent upon the actual option the string values will be interpreted
4737 as numbers, colour names, normal text etc., but there also exists
4738 a special kind of string value, the
4739 .Dq boolean string ,
4740 which must either be a decimal integer (in which case
4744 and any other value is true) or any of the (case-insensitive) strings
4749 for a false boolean and
4754 for a true boolean; a special kind of boolean string is the
4756 which is a boolean string that can optionally be prefixed with the
4757 (case-insensitive) term
4761 which causes prompting of the user in interactive mode, with the given
4762 boolean as the default value.
4764 .\" .Ss "Initial settings" {{{
4765 .\" (Keep in sync: ./main.c:_startup(), ./nail.rc, ./nail.1:"Initial settings"!)
4766 .Ss "Initial Settings"
4768 The standard POSIX 2008/Cor 1-2013 mandates the following initial
4774 .Pf no Va autoprint ,
4788 .Pf no Va ignoreeof ,
4790 .Pf no Va keepsave ,
4792 .Pf no Va outfolder ,
4797 (note that \*(UA deviates from the standard by using
4801 special prompt escape results in
4803 being printed unless
4809 .Pf no Va sendwait ,
4818 Notes: \*(UA doesn't support the
4820 variable \(en use command line options or
4821 .Va sendmail-arguments
4822 to pass options through to a MTA.
4823 And the default global
4825 file (which is loaded unless the
4827 command line flag has been used or the
4828 .Ev NAIL_NO_SYSTEM_RC
4829 environment variable is set) bends those initial settings a bit, e.g.,
4830 it sets the variables
4835 to name a few, calls
4837 etc., and should thus be taken into account.
4840 .\" .Ss "Variables" {{{
4843 .Bl -tag -width ".It Va _utoprin_"
4845 .It Va add-file-recipients
4846 \*(BO When file or pipe recipients have been specified,
4847 mention them in the corresponding address fields of the message instead
4848 of silently stripping them from their recipient list.
4849 By default such addressees are not mentioned.
4851 .Mx Va agent-shell-lookup
4852 .It Va agent-shell-lookup-USER@HOST , agent-shell-lookup-HOST , \
4854 \*(IN\*(OP Account passwords can be fetched via an external agent
4855 program in order to permit encrypted password storage \(en see
4856 .Sx "On URL syntax and credential lookup"
4857 for more on credential lookup.
4858 If this is set then the content is interpreted as a shell command the
4859 output of which (with newline characters removed) is treated as the
4860 account password shall the command succeed (and have produced non-empty
4861 non-newline output); e.g., via
4863 .Bd -literal -offset indent
4864 $ echo PASSWORD > .pass
4866 $ eval `gpg-agent --daemon \e
4867 --pinentry-program=/usr/bin/pinentry-curses \e
4868 --max-cache-ttl 99999 --default-cache-ttl 99999`
4869 $ echo 'set agent-shell-lookup="gpg -d .pass.gpg"' \e
4873 A couple of environment variables will be set for the agent:
4875 .Bl -tag -compact -width ".It Ev _AIL_TMPDIR[337]"
4877 The temporary directory that \*(UA uses.
4878 Usually identical to
4880 but guaranteed to be set and usable by child processes;
4881 to ensure the latter condition for
4887 for which the password is looked up.
4888 .It Ev NAIL_USER_ENC
4889 The URL percent-encoded variant of
4892 The plain machine hostname of the user account.
4893 .It Ev NAIL_HOST_PORT
4896 (hostname possibly including port) of the user account.
4901 \*(BO Causes only the local part to be evaluated
4902 when comparing addresses.
4906 \*(BO Causes messages saved in
4908 to be appended to the end rather than prepended.
4909 This should always be set.
4913 \*(BO Causes \*(UA to prompt for the subject of each message sent.
4914 If the user responds with simply a newline,
4915 no subject field will be sent.
4919 \*(BO Causes the prompts for
4923 lists to appear after the message has been edited.
4927 \*(BO If set, \*(UA asks for files to attach at the end of each message,
4928 shall the list be found empty at that time.
4929 An empty line finalizes the list.
4933 \*(BO Causes the user to be prompted for carbon copy recipients
4934 (at the end of each message if
4938 are set) shall the list be found empty (at that time).
4939 An empty line finalizes the list.
4943 \*(BO Causes the user to be prompted for blind carbon copy
4944 recipients (at the end of each message if
4948 are set) shall the list be found empty (at that time).
4949 An empty line finalizes the list.
4953 \*(BO\*(OP Causes the user to be prompted if the message is to be
4954 signed at the end of each message.
4957 variable is ignored when this variable is set.
4961 \*(BO Alternative name for
4968 .It Va attachment-ask-content-description , \
4969 attachment-ask-content-disposition , \
4970 attachment-ask-content-id , \
4971 attachment-ask-content-type
4972 \*(BO If set then the user will be prompted for some attachment
4973 information when editing the attachment list.
4974 It is advisable to not use these but for the first of the variables;
4975 even for that it has to be noted that the data is used
4981 A sequence of characters to print in the
4985 as shown in the display of
4987 each for one type of messages (see
4988 .Sx "Message states" ) ,
4989 with the default being
4992 .Ql NU\ \ *HMFAT+\-$~
4997 environment variable are set, in the following order:
4999 .Bl -tag -compact -offset indent -width ".It Ql _"
5021 start of a collapsed thread.
5023 an uncollapsed thread (TODO ignored for now).
5027 classified as possible spam.
5033 Specifies a list of recipients to which a blind carbon copy of each
5034 outgoing message will be sent automatically.
5038 Specifies a list of recipients to which a carbon copy of each outgoing
5039 message will be sent automatically.
5043 \*(BO Causes threads to be collapsed automatically when threaded mode
5050 \*(BO Causes the delete command to behave like
5052 thus, after deleting a message the next one will be typed automatically.
5056 \*(BO\*(OB Causes threaded mode (see the
5058 command) to be entered automatically when a folder is opened.
5060 .Ql autosort=thread .
5064 Causes sorted mode (see the
5066 command) to be entered automatically with the value of this option as
5067 sorting method when a folder is opened, e.g.,
5068 .Ql set autosort=thread .
5072 \*(BO Enables the substitution of
5074 by the contents of the last command line in shell escapes.
5077 .It Va batch-exit-on-error
5078 \*(BO If the batch mode has been enabled via the
5080 command line option, then this variable will be consulted whenever \*(UA
5081 completes one operation (returns to the command prompt); if it is set
5082 then \*(UA will terminate if the last operation generated an error.
5086 \*(BO Causes automatic display of a header summary after executing a
5092 \*(BO Sets some cosmetical features to traditional BSD style;
5093 has the same affect as setting
5095 and all other variables prefixed with
5097 it also changes the meaning of the \*(UA specific
5104 \*(BO Changes the letters shown in the first column of a header
5105 summary to traditional BSD style.
5109 \*(BO Changes the display of columns in a header summary to traditional
5114 \*(BO Changes some informational messages to traditional BSD style.
5120 field to appear immediately after the
5122 field in message headers and with the
5124 .Sx "TILDE ESCAPES" .
5128 \*(BO Changes the output format of the
5130 command to traditional BSD style.
5134 The value that should appear in the
5138 MIME header fields when no character set conversion of the message data
5140 This defaults to US-ASCII, and the chosen character set should be
5141 US-ASCII compatible.
5145 \*(OP The default 8-bit character set that is used as an implicit last
5146 member of the variable
5148 This defaults to UTF-8.
5149 If no character set conversion capabilities are available in \*(UA then
5150 the only supported character set is
5152 Refer to the section
5153 .Sx "Character sets"
5154 for the complete picture of character set conversion in \*(UA.
5157 .It Va charset-unknown-8bit
5158 \*(OP RFC 1428 specifies conditions when internet mail gateways shall
5160 the content of a mail message by using a character set with the name
5162 Because of the unclassified nature of this character set \*(UA will not
5163 be capable to convert this character set to any other character set.
5164 If this variable is set any message part which uses the character set
5166 is assumed to really be in the character set given in the value,
5167 otherwise the (final) value of
5169 is used for this purpose.
5173 The default value for the
5178 .It Va colour-disable
5179 \*(BO\*(OP Forcefully disable usage of colours.
5180 Also see the section
5181 .Sx "Coloured message display" .
5185 \*(OP The colour specification for so-called
5189 .Sx "Coloured message display"
5190 for the format of the value.
5193 .It Va colour-header
5194 \*(OP The colour specification for header lines.
5197 .It Va colour-msginfo
5198 \*(OP The colour specification for the introductional message info line.
5202 \*(BO\*(OP Wether colour shall be used for output that is paged through
5204 Note that pagers may need special flags, e.g.,
5212 in order to support colours; therefore \*(UA will inspect the variable
5214 \(en if that starts with the string
5216 a non-existing environment variable
5223 will optionally be set to
5225 Also see the section
5226 .Sx "Coloured message display"
5230 .It Va colour-partinfo
5231 \*(OP The colour specification for MIME part info lines.
5235 \*(OP A comma-separated list of
5237 inals for which coloured message display can be used.
5238 Entries only need to be added if the string
5240 isn't part of the terminal name itself; the default value is
5242 .Dl cons25,linux,rxvt,rxvt-unicode,\:screen,\:sun,\:vt100,\:vt220,\:\
5246 .It Va colour-uheader
5247 \*(OP The colour specification for those header lines that have been
5249 .Va colour-user-headers
5252 .Sx "Coloured message display" .
5255 .It Va colour-user-headers
5256 A comma separated list of (case-insensitive) header names which should
5257 be colourized with the alternative
5260 The default value is
5265 In a(n interactive) terminal session, then if this valued option is set
5266 it'll be used as a threshold to determine how many lines the given
5267 output has to span before it will be displayed via the configured
5271 can be forced by setting this to the value
5273 setting it without a value will deduce the current height of the
5274 terminal screen to compute the treshold (see
5284 the message date, if any is to be displayed according to the format of
5286 is by default taken from the
5288 line of the message.
5289 If this variable is set the date as given in the
5291 header field is used instead, converted to local time.
5292 To control the display format of the date assign a valid
5297 format should not be used, because \*(UA doesn't take embedded newlines
5298 into account when calculating how many lines fit onto the screen.)
5300 .Va datefield-markout-older .
5303 .It Va datefield-markout-older
5304 This option, when set in addition to
5308 messages (concept is rather comparable to the
5310 option of the POSIX utility
5312 The content interpretation is identical to
5317 \*(BO Enables debug messages and obsoletion warnings, disables the
5318 actual delivery of messages and also implies
5325 \*(BY\*(OP\*(OB When an IMAP mailbox is selected and this variable is set,
5326 no connection to the server is initiated.
5327 Instead, data is obtained from the local cache (see
5330 Mailboxes that are not present in the cache
5331 and messages that have not yet entirely been fetched from the server
5333 to fetch all messages in a mailbox at once,
5335 .No ` Ns Li copy * /dev/null Ns '
5336 can be used while still in connected mode.
5337 Changes that are made to IMAP mailboxes in disconnected mode are queued
5338 and committed later when a connection to that server is made.
5339 This procedure is not completely reliable since it cannot be guaranteed
5340 that the IMAP unique identifiers (UIDs) on the server still match the
5341 ones in the cache at that time.
5344 when this problem occurs.
5346 .It Va disconnected-USER@HOST
5347 The specified account is handled as described for the
5350 but other accounts are not affected.
5353 .It Va disposition-notification-send
5355 .Ql Disposition-Notification-To:
5356 header (RFC 3798) with the message.
5360 .\" TODO .It Va disposition-notification-send-HOST
5362 .\".Va disposition-notification-send
5363 .\" for SMTP accounts on a specific host.
5364 .\" TODO .It Va disposition-notification-send-USER@HOST
5366 .\".Va disposition-notification-send
5367 .\"for a specific account.
5371 \*(BO When dot is set, a period
5373 on a line by itself during message input in (interactive) compose mode
5374 will be treated as end-of-message (in addition to the normal end-of-file
5383 .It Va dotlock-ignore-error
5384 \*(BO\*(OP Synchronization of mailboxes which \*(UA treats as system
5385 mailboxes (see the command
5387 will be protected with so-called dotlock files\(emthe traditional mail
5388 spool file locking method\(emin addition to system file locking.
5389 Because \*(UA ships with a privilege-separated dotlock creation program
5390 that should always be able to create such a dotlock file there is no
5391 good reason to ignore dotlock file creation errors, and thus these are
5392 fatal unless this variable is set.
5396 \*(BO If this variable is set then the editor is started automatically
5397 when a message is composed in interactive mode, as if the
5403 variable is implied for this automatically spawned editor session.
5407 \*(BO When a message is edited while being composed,
5408 its header is included in the editable text.
5419 fields are accepted within the header, other fields are ignored.
5423 \*(BO When entering interactive mode \*(UA normally writes
5424 .Dq \&No mail for user
5425 and exits immediately.
5426 If this option is set \*(UA starts even with an empty mailbox.
5430 Suggestion for the MIME encoding to use in outgoing text messages
5432 Valid values are the default
5433 .Ql quoted-printable ,
5438 may cause problems when transferring mail messages over channels that
5439 are not ESMTP (RFC 1869) compliant.
5440 If there is no need to encode a message,
5442 transfer mode is always used regardless of this variable.
5443 Binary data is always encoded as
5448 If defined, the first character of this option
5449 gives the character to use in place of
5452 .Sx "TILDE ESCAPES" .
5456 If not set then file and command pipeline targets are not allowed,
5457 and any such address will be filtered out, giving a warning message.
5458 If set without a value then all possible recipient address
5459 specifications will be accepted \(en see the section
5460 .Sx "On sending mail, and non-interactive mode"
5462 To accept them, but only in interactive mode, or when tilde commands
5463 were enabled explicitly by using one of the command line options
5467 set this to the (case-insensitive) value
5469 (note right now this is actually like setting
5470 .Ql restrict,-all,+name,+addr ) .
5472 In fact the value is interpreted as a comma-separated list of values.
5475 then the existence of disallowed specifications is treated as a hard
5476 send error instead of only filtering them out.
5477 The remaining values specify wether a specific type of recipient
5478 address specification is allowed (optionally indicated by a plus sign
5480 prefix) or disallowed (prefixed with a hyphen
5484 addresses all possible address specifications,
5488 command pipeline targets,
5490 plain user names and (MTA) aliases (\*(OB
5492 may be used as an alternative syntax to
5497 These kind of values are interpreted in the given order, so that
5498 .Ql restrict,\:fail,\:+file,\:-all,\:+addr
5499 will cause hard errors for any non-network address recipient address
5500 unless \*(UA is in interactive mode or has been started with the
5504 command line option; in the latter case(s) any address may be used, then.
5508 Unless this variable is set additional mail-transfer-agent (MTA)
5509 arguments from the command line, as can be given after a
5511 separator, are ignored due to safety reasons.
5512 However, if set to the special value
5514 then the presence of additional MTA arguments is treated as a hard
5515 error that causes \*(UA to exit with failure status.
5516 A lesser strict variant is the otherwise identical
5518 which does accept such arguments in interactive mode, or if tilde
5519 commands were enabled explicitly by using one of the command line options
5526 \*(RO Information on the features compiled into \*(UA \(en the content
5527 of this variable is identical to the output of the command
5532 \*(BO This option reverses the meanings of a set of reply commands,
5533 turning the lowercase variants, which by default address all recipients
5534 included in the header of a message
5535 .Pf ( Ic reply , respond , followup )
5536 into the uppercase variants, which by default address the sender only
5537 .Pf ( Ic Reply , Respond , Followup )
5540 .Ic replysender , respondsender , followupsender
5542 .Ic replyall , respondall , followupall
5543 are not affected by the current setting of
5548 .It Va file-hook-load-EXTENSION , file-hook-save-EXTENSION
5549 It is possible to install file hooks which will be used by the
5551 command in order to be able to transparently handle (through an
5552 intermediate temporary file) files with specific
5554 s: the variable values can include shell snippets and are expected to
5555 write data to standard output / read data from standard input,
5557 \*(ID The variables may not be changed while there is a mailbox
5559 .Bd -literal -offset indent
5560 set file-hook-load-xy='echo >&2 XY-LOAD; gzip -cd' \e
5561 file-hook-save-xy='echo >&2 XY-SAVE; gzip -c' \e
5562 record=+null-sent.xy
5567 The name of the directory to use for storing folders of messages.
5568 All folder names that begin with
5570 refer to files below it.
5571 The same special conventions as documented for the
5573 command may be used when specifying a new value for
5575 but be aware that the expansion is fully performed immediately.
5576 E.g., if the expanded name refers to an IMAP account, all names that
5577 begin with `+' refer to IMAP mailboxes below the
5581 Note: some IMAP servers do not accept the creation of mailboxes in
5582 the hierarchy base, but require that they are created as subfolders of
5583 `INBOX' \(en with such servers a folder name of the form
5585 .Dl imaps://mylogin@imap.myisp.example/INBOX.
5587 should be used (the last character is the server's hierarchy delimiter).
5588 Folder names prefixed by `+' will then refer to folders below `INBOX',
5589 while folder names prefixed by `@' refer to folders below the hierarchy
5593 namespace command for a method to detect the appropriate prefix and
5598 This variable can be set to the name of a
5600 macro which will be called whenever a
5603 The macro will also be invoked when new mail arrives,
5604 but message lists for commands executed from the macro
5605 only include newly arrived messages then.
5608 are activated in a folder hook, then the covered settings will be
5609 reverted once the folder is left again.
5610 .Bd -filled -offset indent
5612 Macro behaviour, including option localization, will change in v15.
5613 To be on the absolutely safe side and avoid any surprises it may be wise
5614 to use wrappers that depend on the program version, e.g.,:
5616 .Bd -literal -offset indent
5617 if $version-major < 15
5623 echo "Please re-verify sent-hook (post v15)"
5626 folder-hook-+sent=sent-hook
5630 .It Va folder-hook-FOLDER
5635 Unlike other folder specifications, the fully expanded name of a folder,
5636 without metacharacters, is used to avoid ambiguities.
5637 However, if the mailbox resides under
5641 specification is tried in addition, e.g., if
5645 (and thus relative to the user's home directory) then
5646 .Pa /home/usr1/mail/sent
5648 .Ql folder-hook-/home/usr1/mail/sent
5649 first, but then followed by
5650 .Ql folder-hook-+sent .
5654 \*(BO Controls wether a
5655 .Ql Mail-Followup-To:
5656 header is generated when sending messages to known mailing lists.
5658 .Va followup-to-honour
5660 .Ic mlist , mlsubscribe , reply
5665 .It Va followup-to-honour
5667 .Ql Mail-Followup-To:
5668 header is honoured when group-replying to a message via
5672 This is a quadoption; if set without a value it defaults to
5682 .It Va forward-as-attachment
5683 \*(BO Original messages are normally sent as inline text with the
5686 and only the first part of a multipart message is included.
5687 With this option messages are sent as unmodified MIME
5689 attachments with all of their parts included.
5693 The address (or a list of addresses) to put into the
5695 field of the message header, quoting RFC 5322:
5696 the author(s) of the message, that is, the mailbox(es) of the person(s)
5697 or system(s) responsible for the writing of the message.
5698 If replying to messages these addresses are handled as if they were in
5702 If the machine's hostname is not valid at the Internet (for example at
5703 a dialup machine) then either this variable or
5708 adds even more fine-tuning capabilities),
5712 contains more than one address,
5715 variable is required (according to the standard RFC 5322).
5719 \*(BO When replying to or forwarding a message \*(UA normally removes
5720 the comment and name parts of email addresses.
5721 If this variable is set such stripping is not performed,
5722 and comments, names etc. are retained.
5726 The string to print before the text of a message with the
5730 .Va forward-as-attachment
5733 .Dq -------- Original Message --------
5734 if unset; No heading is printed if it is set to the empty string.
5738 \*(BO Causes the header summary to be written at startup and after
5739 commands that affect the number of messages or the order of messages in
5740 the current folder; enabled by default.
5741 The command line option
5749 A format string to use for the summary of
5751 similar to the ones used for
5754 Format specifiers in the given string start with a percent character
5756 and may be followed by an optional decimal number indicating the field
5757 width \(em if that is negative, the field is to be left-aligned.
5758 Valid format specifiers are:
5761 .Bl -tag -compact -offset indent -width "_%%_"
5763 A plain percent character.
5766 a space character but for the current message
5768 for which it expands to
5772 a space character but for the current message
5774 for which it expands to
5777 \*(OP The spam score of the message, as has been classified via the
5780 Prints only a replacement character if there is no spam support.
5782 Message attribute character (status flag); the actual content can be
5786 The date when the message was received, or the date found in the
5790 variable is set (optionally to a date display format string).
5792 The indenting level in threaded mode.
5794 The address of the message sender.
5796 The message thread tree structure.
5797 (Note that this format doesn't support a field width.)
5799 The number of lines of the message, if available.
5803 The number of octets (bytes) in the message, if available.
5805 Message subject (if any).
5807 Message subject (if any) in double quotes.
5809 Message recipient flags: is the addressee of the message a known or
5810 subscribed mailing list \(en see
5815 The position in threaded/sorted order.
5819 .Ql %>\&%a\&%m\ %-18f\ %16d\ %4l/%\-5o\ %i%-s ,
5821 .Ql %>\&%a\&%m\ %20-f\ \ %16d\ %3l/%\-5o\ %i%-S
5832 .It Va headline-bidi
5833 Bidirectional text requires special treatment when displaying headers,
5834 because numbers (in dates or for file sizes etc.) will not affect the
5835 current text direction, in effect resulting in ugly line layouts when
5836 arabic or other right-to-left text is to be displayed.
5837 On the other hand only a minority of terminals is capable to correctly
5838 handle direction changes, so that user interaction is necessary for
5840 Note that extended host system support is required nonetheless, e.g.,
5841 detection of the terminal character set is one precondition;
5842 and this feature only works in an Unicode (i.e., UTF-8) locale.
5844 In general setting this variable will cause \*(UA to encapsulate text
5845 fields that may occur when printing
5847 (and some other fields, like dynamic expansions in
5849 with special Unicode control sequences;
5850 it is possible to fine-tune the terminal support level by assigning
5852 no value (or any value other than
5857 will make \*(UA assume that the terminal is capable to properly deal
5858 with Unicode version 6.3, in which case text is embedded in a pair of
5859 U+2068 (FIRST STRONG ISOLATE) and U+2069 (POP DIRECTIONAL ISOLATE)
5861 In addition no space on the line is reserved for these characters.
5863 Weaker support is chosen by using the value
5865 (Unicode 6.3, but reserve the room of two spaces for writing the control
5866 sequences onto the line).
5871 select Unicode 1.1 support (U+200E, LEFT-TO-RIGHT MARK); the latter
5872 again reserves room for two spaces in addition.
5876 \*(OP If a command line editor is available then this can be set to
5877 name the (expandable) path of the location of a permanent history file.
5880 .It Va history-gabby
5881 \*(BO\*(OP Add more entries to the history as is normally done.
5884 .It Va history-gabby-persist
5885 \*(BO\*(OP \*(UA's own MLE will not save the additional
5887 entries in persistent storage unless this variable is set.
5888 On the other hand it will not loose the knowledge of wether a persistent
5889 entry was gabby or not.
5895 \*(OP If a command line editor is available this value restricts the
5896 amount of history entries that are saved into a set and valid
5898 A value of less than 0 disables this feature;
5899 note that loading and incorporation of
5901 upon program startup can also be suppressed by doing this.
5902 An unset or invalid value, or 0, causes a default value to be used.
5903 Dependent on the available command line editor this will also define the
5904 number of history entries in memory;
5905 it is also editor-specific wether runtime updates of this value will be
5910 \*(BO This option is used to hold messages in the system mailbox,
5911 and it is set by default.
5915 Use this string as hostname when expanding local addresses instead of
5916 the value obtained from
5927 transport is not used then it is normally the responsibility of the MTA
5928 to create these fields, \*(IN in conjunction with
5932 also influences the results;
5933 you should produce some test messages with the desired combination of
5942 \*(BO\*(OP Can be used to turn off the automatic conversion of domain
5943 names according to the rules of IDNA (internationalized domain names
5945 Since the IDNA code assumes that domain names are specified with the
5947 character set, an UTF-8 locale charset is required to represent all
5948 possible international domain names (before conversion, that is).
5952 \*(BO Ignore interrupt signals from the terminal while entering
5953 messages; instead echo them as
5955 characters and discard the current line.
5959 \*(BO Ignore end-of-file conditions
5960 .Pf ( Ql control-D )
5961 in compose mode on message input and in interactive command input.
5962 If set an interactive command input session can only be left by
5963 explicitly using one of the commands
5967 and message input in compose mode can only be terminated by entering
5970 on a line by itself or by using the
5972 .Sx "TILDE ESCAPES" ;
5974 overrides a setting of
5978 .It Va imap-auth-USER@HOST , imap-auth
5979 \*(OP\*(OB Sets the IMAP authentication method.
5980 Valid values are `login' for the usual password-based authentication
5982 `cram-md5', which is a password-based authentication that does not send
5983 the password over the network in clear text,
5984 and `gssapi' for GSS-API based authentication.
5988 \*(OP\*(OB Enables caching of IMAP mailboxes.
5989 The value of this variable must point to a directory that is either
5990 existent or can be created by \*(UA.
5991 All contents of the cache can be deleted by \*(UA at any time;
5992 it is not safe to make assumptions about them.
5994 .Mx Va imap-keepalive
5995 .It Va imap-keepalive-USER@HOST , imap-keepalive-HOST , imap-keepalive
5996 \*(OP\*(OB IMAP servers may close the connection after a period of
5997 inactivity; the standard requires this to be at least 30 minutes,
5998 but practical experience may vary.
5999 Setting this variable to a numeric `value' greater than 0 causes
6000 a `NOOP' command to be sent each `value' seconds if no other operation
6004 .It Va imap-list-depth
6005 \*(OP\*(OB When retrieving the list of folders on an IMAP server, the
6007 command stops after it has reached a certain depth to avoid possible
6009 The value of this variable sets the maximum depth allowed.
6011 If the folder separator on the current IMAP server is a slash `/',
6012 this variable has no effect and the
6014 command does not descend to subfolders.
6016 .Mx Va imap-use-starttls
6017 .It Va imap-use-starttls-USER@HOST , imap-use-starttls-HOST , imap-use-starttls
6018 \*(OP\*(OB Causes \*(UA to issue a `STARTTLS' command to make an unencrypted
6019 IMAP session SSL/TLS encrypted.
6020 This functionality is not supported by all servers,
6021 and is not used if the session is already encrypted by the IMAPS method.
6032 option for indenting messages,
6033 in place of the normal tabulator character
6035 which is the default.
6036 Be sure to quote the value if it contains spaces or tabs.
6040 \*(BO If set, an empty mailbox file is not removed.
6041 This may improve the interoperability with other mail user agents
6042 when using a common folder directory, and prevents malicious users
6043 from creating fake mailboxes in a world-writable spool directory.
6044 Note this only applies to local regular (MBOX) files, other mailbox
6045 types will never be removed.
6048 .It Va keep-content-length
6049 \*(BO When (editing messages and) writing
6051 mailbox files \*(UA can be told to keep the
6055 header fields that some MUAs generate by setting this variable.
6056 Since \*(UA does neither use nor update these non-standardized header
6057 fields (which in itself shows one of their conceptual problems),
6058 stripping them should increase interoperability in between MUAs that
6059 work with with same mailbox files.
6060 Note that, if this is not set but
6061 .Va writebackedited ,
6062 as below, is, a possibly performed automatic stripping of these header
6063 fields already marks the message as being modified.
6067 \*(BO When a message is saved it is usually discarded from the
6068 originating folder when \*(UA is quit.
6069 Setting this option causes all saved message to be retained.
6072 .It Va line-editor-cursor-right
6073 \*(OP If the builtin command line editor is used, actions which are
6074 based on rightwise movement may not work on some terminals.
6075 If you encounter such problems, set this variable to the terminal
6076 control sequence that is necessary to move the cursor one column to the
6080 which should work for most terminals.
6087 and other control character have to be written as shell-style escape
6094 .It Va line-editor-disable
6095 \*(BO Turn off any enhanced line editing capabilities (see
6096 .Sx "Command line editor"
6101 \*(BO When a message is replied to and this variable is set,
6102 it is marked as having been answered.
6103 This mark has no technical meaning in the mail system;
6104 it just causes messages to be marked in the header summary,
6105 and makes them specially addressable.
6109 \*(BO \*(UA generates and expects fully RFC 4155 compliant MBOX text
6111 Messages which are fetched over the network or from within already
6112 existing Maildir (or any non-MBOX) mailboxes may require so-called
6114 quoting (insertion of additional
6116 characters to prevent line content misinterpretation) to be applied in
6117 order to be storable in MBOX mailboxes, however, dependent on the
6118 circumspection of the message producer.
6119 (E.g., \*(UA itself will, when newly generating messages, choose a
6120 .Pf Content-Transfer- Va encoding
6121 that prevents the necessity for such quoting \(en a necessary
6122 precondition to ensure message checksums won't change.)
6124 By default \*(UA will perform this
6126 quoting in a way that results in a MBOX file that is compatible with
6127 the POSIX MBOX layout, which means that, in order not to exceed the
6128 capabilities of simple applications, many more
6130 lines get quoted (thus modified) than necessary according to RFC 4155.
6131 Set this option to instead generate MBOX files which comply to RFC 4155.
6135 \*(BO Internal development variable.
6138 .It Va message-id-disable
6139 \*(BO By setting this option the generation of
6141 can be completely suppressed, effectively leaving this task up to the
6142 mail-transfer-agent (MTA) or the SMTP server.
6143 (According to RFC 5321 your SMTP server is not required to add this
6144 field by itself, so you should ensure that it accepts messages without a
6148 .It Va message-inject-head
6149 A string to put at the beginning of each new message.
6150 The escape sequences tabulator
6157 .It Va message-inject-tail
6158 A string to put at the end of each new message.
6159 The escape sequences tabulator
6167 \*(BO Usually, when an
6169 expansion contains the sender, the sender is removed from the expansion.
6170 Setting this option suppresses these removals.
6175 option to be passed to mail-transfer-agents (MTAs);
6176 though most of the modern MTAs don't (no longer) document this flag, no
6177 MTA is known which doesn't support it (for historical compatibility).
6180 .It Va mime-allow-text-controls
6181 \*(BO When sending messages, each part of the message is MIME-inspected
6182 in order to classify the
6185 .Ql Content-Transfer-Encoding:
6188 that is required to send this part over mail transport, i.e.,
6189 a computation rather similar to what the
6191 command produces when used with the
6195 This classification however treats text files which are encoded in
6196 UTF-16 (seen for HTML files) and similar character sets as binary
6197 octet-streams, forcefully changing any
6202 .Ql application/octet-stream :
6203 If that actually happens a yet unset charset MIME parameter is set to
6205 effectively making it impossible for the receiving MUA to automatically
6206 interpret the contents of the part.
6208 If this option is set, and the data was unambiguously identified as text
6209 data at first glance (by a
6213 file extension), then the original
6215 will not be overwritten.
6218 .It Va mime-alternative-favour-rich
6219 \*(BO If this variable is set then rich MIME alternative parts (e.g.,
6220 HTML) will be preferred in favour of included plain text versions when
6221 displaying messages, provided that a handler exists which produces
6222 output that can be (re)integrated into \*(UA's normal visual display.
6223 (E.g., at the time of this writing some newsletters ship their full
6224 content only in the rich HTML part, whereas the plain text part only
6225 contains topic subjects.)
6228 .It Va mime-counter-evidence
6231 field is used to decide how to handle MIME parts.
6232 Some MUAs however don't use
6234 or a similar mechanism to correctly classify content, but simply specify
6235 .Ql application/octet-stream ,
6236 even for plain text attachments like
6238 If this variable is set then \*(UA will try to classify such MIME
6239 message parts on its own, if possible, for example via a possibly
6240 existent attachment filename.
6241 A non-empty value may also be given, in which case a number is expected,
6242 actually a carrier of bits.
6243 Creating the bit-carrying number is a simple addition:
6244 .Bd -literal -offset indent
6245 ? !echo Value should be set to $((2 + 4 + 8))
6246 Value should be set to 14
6249 .Bl -bullet -compact
6251 If bit two is set (2) then the detected
6253 content-type will be carried along with the message and be used for
6255 .Va pipe-TYPE/SUBTYPE
6256 is responsible for the MIME part, shall that question arise;
6257 when displaying such a MIME part the part-info will indicate the
6258 overridden content-type by showing a plus-sign
6261 If bit three is set (4) then the counter-evidence is always produced
6262 and a positive result will be used as the MIME type, even forcefully
6263 overriding the parts given MIME type.
6265 If bit four is set (8) then as a last resort the actual content of
6266 .Ql application/octet-stream
6267 parts will be inspected, so that data which looks like plain text can be
6272 .It Va mimetypes-load-control
6273 This option can be used to control which of the
6275 databases are loaded by \*(UA, as furtherly described in the section
6276 .Sx "The mime.types files" .
6279 is part of the option value, then the user's personal
6281 file will be loaded (if it exists); likewise the letter
6283 controls loading of the system wide
6284 .Pa /etc/mime.types ;
6285 directives found in the user file take precedence, letter matching is
6287 If this option is not set \*(UA will try to load both files.
6288 Incorporation of the \*(UA-builtin MIME types cannot be suppressed,
6289 but they will be matched last.
6291 More sources can be specified by using a different syntax: if the
6292 value string contains an equals sign
6294 then it is instead parsed as a comma-separated list of the described
6297 pairs; the given filenames will be expanded and loaded, and their
6298 content may use the extended syntax that is described in the section
6299 .Sx "The mime.types files" .
6300 Directives found in such files always take precedence (are prepended to
6301 the MIME type cache).
6304 .It Va NAIL_EXTRA_RC
6305 The name of an optional startup file to be read after
6307 This variable has an effect only if it is set in
6311 it is not imported from the environment in order to honour
6312 .Ql MAILRC=/dev/null Ns /
6315 Use this file for commands that are not understood by other POSIX
6320 .It Va netrc-lookup-USER@HOST , netrc-lookup-HOST , netrc-lookup
6321 \*(BO\*(IN\*(OP Used to control usage of the users
6323 file for lookup of account credentials, as documented in the section
6324 .Sx "On URL syntax and credential lookup"
6328 .Sx "The .netrc file"
6329 documents the file format.
6333 If this variable has the value
6335 newly created local folders will be in Maildir format.
6339 Checks for new mail in the current folder each time the prompt is
6341 For IMAP mailboxes the server is then polled for new mail,
6342 which may result in delayed operation if the connection to the server is
6344 A Maildir folder must be re-scanned to determine if new mail has arrived.
6346 If this variable is set to the special value
6348 an IMAP server is not actively asked for new mail, but new mail may
6349 still be detected and announced with any other IMAP command that is sent
6351 In either case the IMAP server may send notifications about messages
6352 that have been deleted on the server by another process or client.
6354 .Dq Expunged X messages
6355 is printed regardless of this variable, and message numbers may have
6358 If this variable is set to the special value
6360 then a Maildir folder will not be rescanned completely, but only
6361 timestamp changes are detected.
6365 \*(BO Causes the filename given in the
6368 and the sender-based filenames for the
6372 commands to be interpreted relative to the directory given in the
6374 variable rather than to the current directory,
6375 unless it is set to an absolute pathname.
6379 \*(BO If set, each message feed through the command given for
6381 command prints out is followed by a formfeed character
6385 .It Va password-USER@HOST , password-HOST , password
6386 \*(IN Variable chain that sets a password, which is used in case none has
6387 been given in the protocol and account-specific URL;
6388 as a last resort \*(UA will ask for a password on the user's terminal if
6389 the authentication method requires a password.
6390 Specifying passwords in a startup file is generally a security risk;
6391 the file should be readable by the invoking user only.
6393 .It Va password-USER@HOST
6394 \*(OU (see the chain above for \*(IN)
6395 Set the password for
6399 If no such variable is defined for a host,
6400 the user will be asked for a password on standard input.
6401 Specifying passwords in a startup file is generally a security risk;
6402 the file should be readable by the invoking user only.
6406 \*(BO Send messages to the
6408 command without performing MIME and character set conversions.
6412 .It Va pipe-TYPE/SUBTYPE
6413 When a MIME message part of type
6415 (case-insensitive) is displayed or quoted,
6416 its text is filtered through the value of this variable interpreted as
6420 forces interpretation of the message part as plain text, e.g.,
6421 .Ql set pipe-application/xml=@
6422 will henceforth display XML
6424 (The same could also be achieved by adding a MIME type marker with the
6427 And \*(OPally MIME type handlers may be defined via
6428 .Sx "The Mailcap files"
6429 \(em corresponding flag strings are shown in parenthesis below.)
6434 can in fact be used to adjust usage and behaviour of a following shell
6435 command specification by appending trigger characters to it, e.g., the
6436 following hypothetical command specification could be used:
6437 .Bd -literal -offset indent
6438 set pipe-X/Y="@*!++=@vim ${NAIL_FILENAME_TEMPORARY}"
6442 .Bl -tag -compact -width ".It Ql __"
6444 Simply by using the special
6446 prefix the MIME type (shell command) handler will only be invoked to
6447 display or convert the MIME part if the message is addressed directly
6448 and alone by itself.
6449 Use this trigger to disable this and always invoke the handler
6450 .Pf ( Cd x-mailx-always ) .
6453 If set the handler will not be invoked when a message is to be quoted,
6454 but only when it will be displayed
6455 .Pf ( Cd x-mailx-noquote ) .
6458 The command will be run asynchronously, i.e., without blocking \*(UA,
6459 which may be a handy way to display a, e.g., PDF file while also
6460 continuing to read the mail message
6461 .Pf ( Cd x-mailx-async ) .
6462 Asynchronous execution implies
6466 The command must be run on an interactive terminal, \*(UA will
6467 temporarily release the terminal to it
6468 .Pf ( Cd needsterminal ) .
6469 This flag is mutual exclusive with
6471 will only be used in interactive mode and implies
6475 Request creation of a zero-sized temporary file, the absolute pathname
6476 of which will be made accessable via the environment variable
6477 .Ev NAIL_FILENAME_TEMPORARY
6478 .Pf ( Cd x-mailx-tmpfile ) .
6479 If this trigger is given twice then the file will be unlinked
6480 automatically by \*(UA when the command loop is entered again at latest
6481 .Pf ( Cd x-mailx-tmpfile-unlink ) .
6482 (Don't use this for asynchronous handlers.)
6485 Normally the MIME part content is passed to the handler via standard
6486 input; if this flag is set then the data will instead be written into
6487 .Ev NAIL_FILENAME_TEMPORARY
6488 .Pf ( Cd x-mailx-tmpfile-fill ) ,
6489 the creation of which is implied; note however that in order to cause
6490 deletion of the temporary file you still have to use two plus signs
6495 To avoid ambiguities with normal shell command content you can use
6496 another at-sign to forcefully terminate interpretation of remaining
6498 (Any character not in this list will have the same effect.)
6502 Some information about the MIME part to be displayed is embedded into
6503 the environment of the shell command:
6506 .Bl -tag -compact -width ".It Ev _AIL__ILENAME__ENERATED"
6509 The MIME content-type of the part, if known, the empty string otherwise.
6512 .It Ev NAIL_CONTENT_EVIDENCE
6514 .Va mime-counter-evidence
6515 includes the carry-around-bit (2), then this will be set to the detected
6516 MIME content-type; not only then identical to
6517 .Ev \&\&NAIL_CONTENT
6521 .It Ev NAIL_FILENAME
6522 The filename, if any is set, the empty string otherwise.
6525 .It Ev NAIL_FILENAME_GENERATED
6529 .It Ev NAIL_FILENAME_TEMPORARY
6530 If temporary file creation has been requested through the command prefix
6531 this variable will be set and contain the absolute pathname of the
6536 The temporary directory that \*(UA uses.
6537 Usually identical to
6539 but guaranteed to be set and usable by child processes;
6540 to ensure the latter condition for
6547 .It Va pipe-EXTENSION
6548 This is identical to
6549 .Va pipe-TYPE/SUBTYPE
6552 (normalized to lowercase using character mappings of the ASCII charset)
6553 names a file extension, e.g.,
6555 Handlers registered using this method take precedence.
6558 .It Va pop3-auth-USER@HOST , pop3-auth-HOST , pop3-auth
6559 \*(OP\*(IN Variable chain that sets the POP3 authentication method.
6560 The only possible value as of now is
6562 which is thus the default.
6565 .Mx Va pop3-bulk-load
6566 .It Va pop3-bulk-load-USER@HOST , pop3-bulk-load-HOST , pop3-bulk-load
6567 \*(BO\*(OP When accessing a POP3 server \*(UA loads the headers of
6568 the messages, and only requests the message bodies on user request.
6569 For the POP3 protocol this means that the message headers will be
6571 If this option is set then \*(UA will download only complete messages
6572 from the given POP3 server(s) instead.
6574 .Mx Va pop3-keepalive
6575 .It Va pop3-keepalive-USER@HOST , pop3-keepalive-HOST , pop3-keepalive
6576 \*(OP POP3 servers close the connection after a period of inactivity;
6577 the standard requires this to be at least 10 minutes,
6578 but practical experience may vary.
6579 Setting this variable to a numeric value greater than
6583 command to be sent each value seconds if no other operation is performed.
6586 .It Va pop3-no-apop-USER@HOST , pop3-no-apop-HOST , pop3-no-apop
6587 \*(BO\*(OP Unless this variable is set the
6589 authentication method will be used when connecting to a POP3 server that
6593 is that the password is not sent in clear text over the wire and that
6594 only a single packet is sent for the user/password tuple.
6596 .Va pop3-no-apop-HOST
6599 .Mx Va pop3-use-starttls
6600 .It Va pop3-use-starttls-USER@HOST , pop3-use-starttls-HOST , pop3-use-starttls
6601 \*(BO\*(OP Causes \*(UA to issue a
6603 command to make an unencrypted POP3 session SSL/TLS encrypted.
6604 This functionality is not supported by all servers,
6605 and is not used if the session is already encrypted by the POP3S method.
6607 .Va pop3-use-starttls-HOST
6611 .It Va print-all-chars
6612 \*(BY This option causes all characters to be considered printable.
6613 It is only effective if given in a startup file.
6614 With this option set some character sequences in messages may put the
6615 user's terminal in an undefined state when printed;
6616 it should only be used as a last resort if no working system locale can
6620 .It Va print-alternatives
6621 \*(BO When a MIME message part of type
6622 .Ql multipart/alternative
6623 is displayed and it contains a subpart of type
6625 other parts are normally discarded.
6626 Setting this variable causes all subparts to be displayed,
6627 just as if the surrounding part was of type
6628 .Ql multipart/mixed .
6632 The string printed when a command is accepted.
6633 Prompting may be prevented by either setting this to the null string
6636 The same XSI escape sequences that are understood by the
6638 command may be used within
6641 In addition, the following \*(UA specific additional sequences are
6648 is set, in which case it expands to
6652 is the default value of
6655 which will expand to
6657 if the last command failed and to
6661 which will expand to the name of the currently active
6663 if any, and to the empty string otherwise, and
6665 which will expand to the name of the currently active mailbox.
6666 (Note that the prompt buffer is size-limited, excess is cut off.)
6672 to encapsulate the expansions of the
6676 escape sequences as necessary to correctly display bidirectional text,
6677 this is not true for the final string that makes up
6679 as such, i.e., real BIDI handling is not supported.
6681 When a newer version of the
6683 .Sx "Command line editor"
6684 is used, any escape sequence must itself be encapsulated with another
6685 escape character for usage with the
6687 mechanism: \*(UA configures the control character
6693 \*(BO Suppresses the printing of the version when first invoked.
6697 If set, \*(UA starts a replying message with the original message
6698 prefixed by the value of the variable
6700 Normally, a heading consisting of
6701 .Dq Fromheaderfield wrote:
6702 is printed before the quotation.
6707 variable, this heading is omitted.
6710 is assigned, the headers selected by the
6711 .Ic ignore Ns / Ns Ic retain
6712 commands are printed above the message body,
6715 acts like an automatic
6721 is assigned, all headers are printed above the message body and all MIME
6722 parts are included, making
6724 act like an automatic
6727 .Va quote-as-attachment .
6730 .It Va quote-as-attachment
6731 \*(BO Add the original message in its entirety as a
6733 MIME attachment when replying to a message.
6734 Note this works regardless of the setting of
6739 \*(OP Can be set in addition to
6741 Setting this turns on a more fancy quotation algorithm in that leading
6742 quotation characters are compressed and overlong lines are folded.
6744 can be set to either one or two (space separated) numeric values,
6745 which are interpreted as the maximum (goal) and the minimum line length,
6746 respectively, in a spirit rather equal to the
6748 program, but line-, not paragraph-based.
6749 If not set explicitly the minimum will reflect the goal algorithmically.
6750 The goal can't be smaller than the length of
6752 plus some additional pad.
6753 Necessary adjustments take place silently.
6756 .It Va recipients-in-cc
6757 \*(BO On group replies, specify only the sender of the original mail in
6759 and mention the other recipients in the secondary
6761 By default all recipients of the original mail will be addressed via
6766 If defined, gives the pathname of the folder used to record all outgoing
6768 If not defined, then outgoing mail is not saved.
6769 When saving to this folder fails the message is not sent,
6770 but instead saved to
6774 .It Va record-resent
6775 \*(BO If both this variable and the
6782 commands save messages to the
6784 folder as it is normally only done for newly composed messages.
6787 .It Va reply-in-same-charset
6788 \*(BO If this variable is set \*(UA first tries to use the same
6789 character set of the original message for replies.
6790 If this fails, the mechanism described in
6791 .Sx "Character sets"
6792 is evaluated as usual.
6795 .It Va reply_strings
6796 Can be set to a comma-separated list of (case-insensitive according to
6797 ASCII rules) strings which shall be recognized in addition to the
6800 reply message indicators \(en builtin are
6802 which is mandated by RFC 5322, as well as the german
6807 A list of addresses to put into the
6809 field of the message header.
6810 Members of this list are handled as if they were in the
6815 .It Va reply-to-honour
6818 header is honoured when replying to a message via
6822 This is a quadoption; if set without a value it defaults to
6826 .It Va rfc822-body-from_
6827 \*(BO This variable can be used to force displaying a so-called
6829 line for messages that are embedded into an envelope mail via the
6831 MIME mechanism, for more visual convenience.
6835 \*(BO Enable saving of (partial) messages in
6837 upon interrupt or delivery error.
6841 When \*(UA initially prints the message headers it determines the number
6842 to print by looking at the speed of the terminal.
6843 The faster the terminal, the more it prints.
6844 This option overrides this calculation and specifies how many message
6845 headers are printed.
6846 This number is also used for scrolling with the
6849 Overall screen dimensions and pager usage is influenced by the
6850 environment variables
6858 .It Va searchheaders
6859 \*(BO Expand message-list specifiers in the form
6861 to all messages containing the substring
6865 The string search is case insensitive.
6869 \*(OP A comma-separated list of character set names that can be used in
6870 outgoing internet mail.
6871 The value of the variable
6873 is automatically appended to this list of character-sets.
6874 If no character set conversion capabilities are compiled into \*(UA then
6875 the only supported charset is
6878 .Va sendcharsets-else-ttycharset
6879 and refer to the section
6880 .Sx "Character sets"
6881 for the complete picture of character set conversion in \*(UA.
6884 .It Va sendcharsets-else-ttycharset
6885 \*(BO\*(OP If this variable is set, but
6887 is not, then \*(UA acts as if
6889 had been set to the value of the variable
6891 In effect this combination passes through the message data in the
6892 character set of the current locale (given that
6894 hasn't been set manually), i.e., without converting it to the
6896 fallback character set.
6897 Thus, mail message text will be in ISO-8859-1 encoding when send from
6898 within a ISO-8859-1 locale, and in UTF-8 encoding when send from within
6900 If no character set conversion capabilities are available in \*(UA then
6901 the only supported character set is
6906 An address that is put into the
6908 field of outgoing messages, quoting RFC 5322: the mailbox of the agent
6909 responsible for the actual transmission of the message.
6910 This field should normally not be used unless the
6912 field contains more than one address, on which case it is required.
6915 address is handled as if it were in the
6921 To use an alternate mail transport agent (MTA),
6922 set this option to the full pathname of the program to use.
6923 It may be necessary to set
6924 .Va sendmail-progname
6927 The MTA will be passed command line arguments from several possible
6928 sources: from the variable
6929 .Va sendmail-arguments
6930 if set, from the command line if given and the variable
6933 Argument processing of the MTA will be terminated with a
6937 The otherwise occurring implicit usage of the following MTA command line
6938 arguments can be disabled by setting the boolean option
6939 .Va sendmail-no-default-arguments
6940 (which will also disable passing
6944 (for not treating a line with only a dot
6946 character as the end of input),
6954 option is set); in conjunction with the
6956 command line option \*(UA will also pass
6962 .It Va sendmail-arguments
6963 Arguments to pass through to the Mail-Transfer-Agent can be given via
6965 The content of this variable will be split up in a vector of arguments
6966 which will be joined onto other possible MTA options:
6968 .Dl set sendmail-arguments='-t -X \&"/tmp/my log\&"'
6971 .It Va sendmail-no-default-arguments
6972 \*(BO Unless this option is set \*(UA will pass some well known
6973 standard command line options to the defined
6975 program, see there for more.
6978 .It Va sendmail-progname
6979 Many systems use a so-called
6981 environment to ensure compatibility with
6983 This works by inspecting the name that was used to invoke the mail
6985 If this variable is set then the mailwrapper (the program that is
6986 actually executed when calling
6988 will treat its contents as that name.
6994 \*(BO When sending a message wait until the MTA (including the builtin
6995 SMTP one) exits before accepting further commands.
6997 with this variable set errors reported by the MTA will be recognizable!
6998 If the MTA returns a non-zero exit status,
6999 the exit status of \*(ua will also be non-zero.
7003 \*(BO Setting this option causes \*(UA to start at the last message
7004 instead of the first one when opening a mail folder.
7008 \*(BO Causes \*(UA to use the sender's real name instead of the plain
7009 address in the header field summary and in message specifications.
7013 \*(BO Causes the recipient of the message to be shown in the header
7014 summary if the message was sent by the user.
7018 A string for use with the
7024 A string for use with the
7030 Must correspond to the name of a readable file if set.
7031 The file's content is then appended to each singlepart message
7032 and to the first part of each multipart message.
7033 Be warned that there is no possibility to edit the signature for an
7037 .It Va skipemptybody
7038 \*(BO If an outgoing message does not contain any text in its first or
7039 only message part, do not send it but discard it silently (see also the
7045 \*(OP Specifies a directory with CA certificates in PEM (Privacy
7046 Enhanced Mail) format for verification of S/MIME signed messages.
7049 .It Va smime-ca-file
7050 \*(OP Specifies a file with CA certificates in PEM format for
7051 verification of S/MIME signed messages.
7054 .It Va smime-cipher-USER@HOST , smime-cipher
7055 \*(OP Specifies the cipher to use when generating S/MIME encrypted
7056 messages (for the specified account).
7057 RFC 5751 mandates a default of
7060 Possible values are (case-insensitive and) in decreasing cipher strength:
7068 (DES EDE3 CBC, 168 bits; default if
7070 isn't available) and
7074 The actually available cipher algorithms depend on the cryptographic
7075 library that \*(UA uses.
7076 \*(OP Support for more cipher algorithms may be available through
7077 dynamic loading via, e.g.,
7078 .Xr EVP_get_cipherbyname 3
7079 (OpenSSL) if \*(UA has been compiled to support this.
7082 .It Va smime-crl-dir
7083 \*(OP Specifies a directory that contains files with CRLs in PEM format
7084 to use when verifying S/MIME messages.
7087 .It Va smime-crl-file
7088 \*(OP Specifies a file that contains a CRL in PEM format to use when
7089 verifying S/MIME messages.
7092 .It Va smime-encrypt-USER@HOST
7093 \*(OP If this variable is set, messages send to the given receiver are
7094 encrypted before sending.
7095 The value of the variable must be set to the name of a file that
7096 contains a certificate in PEM format.
7098 If a message is sent to multiple recipients,
7099 each of them for whom a corresponding variable is set will receive an
7100 individually encrypted message;
7101 other recipients will continue to receive the message in plain text
7103 .Va smime-force-encryption
7105 It is recommended to sign encrypted messages, i.e., to also set the
7110 .It Va smime-force-encryption
7111 \*(BO\*(OP Causes \*(UA to refuse sending unencrypted messages.
7114 .It Va smime-no-default-ca
7115 \*(BO\*(OP Don't load default CA locations when verifying S/MIME signed
7120 \*(BO\*(OP S/MIME sign outgoing messages with the user's private key
7121 and include the user's certificate as a MIME attachment.
7122 Signing a message enables a recipient to verify that the sender used
7123 a valid certificate,
7124 that the email addresses in the certificate match those in the message
7125 header and that the message content has not been altered.
7126 It does not change the message text,
7127 and people will be able to read the message as usual.
7129 .Va smime-sign-cert , smime-sign-include-certs
7131 .Va smime-sign-message-digest .
7133 .Mx Va smime-sign-cert
7134 .It Va smime-sign-cert-USER@HOST , smime-sign-cert
7135 \*(OP Points to a file in PEM format.
7136 For the purpose of signing and decryption this file needs to contain the
7137 user's private key as well as his certificate.
7141 is always derived from the value of
7143 (or, if that contains multiple addresses,
7145 For the purpose of encryption the recipient's public encryption key
7146 (certificate) is expected; the command
7148 can be used to save certificates of signed messages (the section
7149 .Sx "Signed and encrypted messages with S/MIME"
7150 gives some details).
7151 This mode of operation is usually driven by the specialized form.
7153 When decrypting messages the account is derived from the recipient
7158 of the message, which are searched for addresses for which such
7160 \*(UA always uses the first address that matches,
7161 so if the same message is sent to more than one of the user's addresses
7162 using different encryption keys, decryption might fail.
7164 .Mx Va smime-sign-include-certs
7165 .It Va smime-sign-include-certs-USER@HOST , smime-sign-include-certs
7166 \*(OP If used, this is supposed to a consist of a comma-separated list
7167 of files, each of which containing a single certificate in PEM format to
7168 be included in the S/MIME message in addition to the
7171 This is most useful for long certificate chains if it is desired to aid
7172 the receiving party's verification process.
7173 Note that top level certificates may also be included in the chain but
7174 don't play a role for verification.
7176 .Va smime-sign-cert .
7177 Remember that for this
7179 refers to the variable
7181 (or, if that contains multiple addresses,
7184 .Mx Va smime-sign-message-digest
7185 .It Va smime-sign-message-digest-USER@HOST , smime-sign-message-digest
7186 \*(OP Specifies the message digest to use when signing S/MIME messages.
7187 RFC 5751 mandates a default of
7189 Possible values are (case-insensitive and) in decreasing cipher strength:
7197 The actually available message digest algorithms depend on the
7198 cryptographic library that \*(UA uses.
7199 \*(OP Support for more message digest algorithms may be available
7200 through dynamic loading via, e.g.,
7201 .Xr EVP_get_digestbyname 3
7202 (OpenSSL) if \*(UA has been compiled to support this.
7203 Remember that for this
7205 refers to the variable
7207 (or, if that contains multiple addresses,
7213 \*(OP Normally \*(UA invokes the program defined via
7215 to transfer messages, as described in
7216 .Sx "On sending mail, and non-interactive mode" .
7219 variable will instead cause SMTP network connections be made to the
7220 server specified therein in order to directly submit the message.
7221 \*(UA knows about three different
7222 .Dq SMTP protocols :
7224 .Bl -bullet -compact
7226 The plain SMTP protocol (RFC 5321) that normally lives on the
7227 server port 25 and requires setting the
7228 .Va smtp-use-starttls
7229 variable to enter a SSL/TLS encrypted session state.
7230 Assign a value like \*(IN
7231 .Ql [smtp://][user[:password]@]server[:port]
7233 .Ql [smtp://]server[:port] )
7234 to choose this protocol.
7236 Then the so-called SMTPS which is supposed to live on server port 465
7237 and is automatically SSL/TLS secured.
7238 Unfortunately it never became a standardized protocol and may thus not
7239 be supported by your hosts network service database
7240 \(en in fact the port number has already been reassigned to other
7243 SMTPS is nonetheless a commonly offered protocol and thus can be
7244 chosen by assigning a value like \*(IN
7245 .Ql smtps://[user[:password]@]server[:port]
7247 .Ql smtps://server[:port] ) ;
7248 due to the mentioned problems it is usually necessary to explicitly
7253 Finally there is the SUBMISSION protocol (RFC 6409), which usually
7254 lives on server port 587 and is practically identically to the SMTP
7255 protocol from \*(UA's point of view beside that; it requires setting the
7256 .Va smtp-use-starttls
7257 variable to enter a SSL/TLS secured session state.
7258 Assign a value like \*(IN
7259 .Ql submission://[user[:password]@]server[:port]
7261 .Ql submission://server[:port] ) .
7264 For more on credentials etc. please see
7265 .Sx "On URL syntax and credential lookup" .
7266 The SMTP transfer is executed in a child process, which runs
7267 asynchronously unless either the
7272 If it receives a TERM signal, it will abort and save the message to
7277 .It Va smtp-auth-USER@HOST , smtp-auth-HOST , smtp-auth
7278 \*(OP Variable chain that sets the SMTP authentication method.
7285 as well as the \*(OPal methods
7291 method doesn't need any user credentials,
7293 requires a user name and all other methods require a user name and
7301 .Va smtp-auth-password
7303 .Va smtp-auth-user ) .
7308 .Va smtp-auth-USER@HOST :
7309 may override dependend on sender address in the variable
7312 .It Va smtp-auth-password
7313 \*(OP\*(OU Sets the global fallback password for SMTP authentication.
7314 If the authentication method requires a password, but neither
7315 .Va smtp-auth-password
7317 .Va smtp-auth-password-USER@HOST
7319 \*(UA will ask for a password on the user's terminal.
7321 .It Va smtp-auth-password-USER@HOST
7323 .Va smtp-auth-password
7324 for specific values of sender addresses, dependent upon the variable
7327 .It Va smtp-auth-user
7328 \*(OP\*(OU Sets the global fallback user name for SMTP authentication.
7329 If the authentication method requires a user name, but neither
7332 .Va smtp-auth-user-USER@HOST
7334 \*(UA will ask for a user name on the user's terminal.
7336 .It Va smtp-auth-user-USER@HOST
7339 for specific values of sender addresses, dependent upon the variable
7343 .It Va smtp-hostname
7344 \*(IN Normally \*(UA uses the variable
7346 to derive the necessary
7348 information to issue a
7353 can be used to use the
7355 from the SMTP account
7362 from the content of this variable (or, if that is the empty string,
7364 or the local hostname as a last resort).
7365 This often allows using an address that is itself valid but hosted by
7366 a provider other than which (in
7368 is about to send the message.
7369 Setting this variable also influences the generated
7372 .Mx Va smtp-use-starttls
7373 .It Va smtp-use-starttls-USER@HOST , smtp-use-starttls-HOST , smtp-use-starttls
7374 \*(BO\*(OP Causes \*(UA to issue a
7376 command to make an SMTP session SSL/TLS encrypted, i.e., to enable
7377 transport layer security.
7381 .It Va spam-interface
7382 \*(OP In order to use any of the spam-related commands (like, e.g.,
7384 the desired spam interface must be defined by setting this variable.
7385 Please refer to the manual section
7387 for the complete picture of spam handling in \*(UA.
7388 All or none of the following interfaces may be available:
7390 .Bl -tag -width ".It Ql _ilte_"
7396 .Pf ( Lk http://spamassassin.apache.org SpamAssassin )
7398 Different to the generic filter interface \*(UA will automatically add
7399 the correct arguments for a given command and has the necessary
7400 knowledge to parse the program's output.
7403 will have been compiled into the \*(UA binary if
7408 Shall it be necessary to define a specific connection type (rather than
7409 using a configuration file for that), the variable
7411 can be used as in, e.g.,
7412 .Ql -d server.example.com -p 783 .
7413 It is also possible to specify a per-user configuration via
7415 Note that this interface doesn't inspect the
7417 flag of a message for the command
7421 \*(UA will directly communicate with the
7427 stream socket as specified in
7429 It is possible to specify a per-user configuration via
7433 generic spam filter support via freely configurable hooks.
7434 This interface is ment for programs like
7438 and requires according behaviour in respect to the hooks' exit
7439 status for at least the command
7442 meaning a message is spam,
7446 for unsure and any other return value indicating a hard error);
7447 since the hooks can include shell code snippets diverting behaviour
7448 can be intercepted as necessary.
7450 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
7453 .Va spamfilter-spam ;
7456 contains examples for some programs.
7457 The process environment of the hooks will have the variables
7458 .Ev NAIL_TMPDIR , TMPDIR
7460 .Ev NAIL_FILENAME_GENERATED
7462 Note that spam score support for
7464 isn't supported unless the \*(OPtional regular expression support is
7466 .Va spamfilter-rate-scanscore
7473 \*(OP Messages that exceed this size won't be passed through to the
7475 .Va spam-interface .
7476 The default is 420000 bytes.
7479 .It Va spamc-command
7480 \*(OP The path to the
7484 .Va spam-interface .
7485 Note that the path is not expanded, but used
7487 A fallback path will have been compiled into the \*(UA binary if the
7488 executable had been found during compilation.
7491 .It Va spamc-arguments
7492 \*(OP Even though \*(UA deals with most arguments for the
7495 automatically, it may at least sometimes be desirable to specifiy
7496 connection-related ones via this variable, e.g.,
7497 .Ql -d server.example.com -p 783 .
7501 \*(OP Specify a username for per-user configuration files for the
7503 .Va spam-interface .
7504 If this is set to the empty string then \*(UA will use the name of the
7510 \*(OP Specify the path of the
7512 domain socket on which
7514 listens for connections for the
7516 .Va spam-interface .
7517 Note that the path is not expanded, but used
7522 \*(OP Specify a username for per-user configuration files for the
7524 .Va spam-interface .
7525 If this is set to the empty string then \*(UA will use the name of the
7534 .It Va spamfilter-ham , spamfilter-noham , \
7535 spamfilter-nospam , spamfilter-rate , spamfilter-spam
7536 \*(OP Command and argument hooks for the
7538 .Va spam-interface .
7541 contains examples for some programs.
7544 .It Va spamfilter-rate-scanscore
7545 \*(OP Because of the generic nature of the
7548 spam scores are not supported for it by default, but if the \*(OPtional
7549 regular expression support is available then setting this variable can
7550 be used to overcome this restriction.
7551 It is interpreted as follows: first a number (digits) is parsed that
7552 must be followed by a semicolon
7554 and an extended regular expression.
7555 Then the latter is used to parse the first output line of the
7557 hook, and, in case the evaluation is successful, the group that has been
7558 specified via the number is interpreted as a floating point scan score.
7562 \*(OP Specifies a directory with CA certificates in PEM (Pricacy
7563 Enhanced Mail) for verification of of SSL/TLS server certificates.
7565 .Xr SSL_CTX_load_verify_locations 3
7566 for more information.
7570 \*(OP Specifies a file with CA certificates in PEM format for
7571 verification of SSL/TLS server certificates.
7573 .Xr SSL_CTX_load_verify_locations 3
7574 for more information.
7577 .It Va ssl-cert-USER@HOST , ssl-cert-HOST , ssl-cert
7578 \*(OP Variable chain that sets the file name for a SSL/TLS client
7579 certificate required by some servers.
7580 This is a direct interface to the
7584 function of the OpenSSL library, if available.
7586 .Mx Va ssl-cipher-list
7587 .It Va ssl-cipher-list-USER@HOST , ssl-cipher-list-HOST , ssl-cipher-list
7588 \*(OP Specifies a list of ciphers for SSL/TLS connections.
7589 This is a direct interface to the
7593 function of the OpenSSL library, if available; see
7595 for more information.
7596 By default \*(UA doesn't set a list of ciphers, which in effect will use a
7598 specific cipher (protocol standards ship with a list of acceptable
7599 ciphers), possibly cramped to what the actually used SSL/TLS library
7600 supports \(en the manual section
7601 .Sx "An example configuration"
7602 also contains a SSL/TLS use case.
7605 .It Va ssl-config-file
7606 \*(OP If this variable is set \*(UA will call
7607 .Xr CONF_modules_load_file 3
7608 to allow OpenSSL to be configured according to the host system wide
7610 If a non-empty value is given then this will be used to specify the
7611 configuration file to be used instead of the global OpenSSL default;
7612 note that in this case it is an error if the file cannot be loaded.
7613 The application name will always be passed as
7618 \*(OP Specifies a file that contains a CRL in PEM format to use when
7619 verifying SSL/TLS server certificates.
7623 \*(OP Specifies a directory that contains files with CRLs in PEM format
7624 to use when verifying SSL/TLS server certificates.
7627 .It Va ssl-key-USER@HOST , ssl-key-HOST , ssl-key
7628 \*(OP Variable chain that sets the file name for the private key of
7629 a SSL/TLS client certificate.
7630 If unset, the name of the certificate file is used.
7631 The file is expected to be in PEM format.
7632 This is a direct interface to the
7636 function of the OpenSSL library, if available.
7639 .It Va ssl-method-USER@HOST , ssl-method-HOST , ssl-method
7641 \*(OB Please use the newer and more flexible
7643 instead: if both values are set,
7645 will take precedence!
7646 Can be set to the following values, the actually used
7648 specification to which it is mapped is shown in parenthesis:
7650 .Pf ( Ql -ALL, TLSv1.2 ) ,
7652 .Pf ( Ql -ALL, TLSv1.1 ) ,
7654 .Pf ( Ql -ALL, TLSv1 )
7657 .Pf ( Ql -ALL, SSLv3 ) ;
7662 and thus includes the SSLv3 protocol.
7663 Note that SSLv2 is no longer supported at all.
7666 .It Va ssl-no-default-ca
7667 \*(BO\*(OP Don't load default CA locations to verify SSL/TLS server
7671 .It Va ssl-protocol-USER@HOST , ssl-protocol-HOST , ssl-protocol
7672 \*(OP Specify the used SSL/TLS protocol.
7673 This is a direct interface to the
7677 function of the OpenSSL library, if available;
7678 otherwise an \*(UA internal parser is used which understands the
7679 following subset of (case-insensitive) command strings:
7685 as well as the special value
7687 Multiple specifications may be given via a comma-separated list which
7688 ignores any whitespace.
7691 plus prefix will enable a protocol, a
7693 minus prefix will disable it, so that
7695 will enable only the TLSv1.2 protocol.
7697 It depends upon the used TLS/SSL library which protocols are actually
7698 supported and which protocols are used if
7700 is not set, but note that SSLv2 is no longer supported at all and
7702 Especially for older protocols explicitly securing
7704 may be worthwile, see
7705 .Sx "An example configuration" .
7709 \*(OP Gives the pathname to an entropy daemon socket, see
7711 Not all SSL/TLS libraries support this.
7714 .It Va ssl-rand-file
7715 \*(OP Gives the pathname to a file with entropy data, see
7716 .Xr RAND_load_file 3 .
7717 If the file is a regular file writable by the invoking user,
7718 new data is written to it after it has been loaded.
7721 .It Va ssl-verify-USER@HOST , ssl-verify-HOST , ssl-verify
7722 \*(OP Variable chain that sets the action to be performed if an error
7723 occurs during SSL/TLS server certificate validation.
7724 Valid (case-insensitive) values are
7726 (fail and close connection immediately),
7728 (ask whether to continue on standard input),
7730 (print a warning and continue),
7732 (do not perform validation).
7738 If only set without an assigned value, then this option inhibits the
7743 header fields that include obvious references to \*(UA.
7744 There are two pitfalls associated with this:
7745 First, the message id of outgoing messages is not known anymore.
7746 Second, an expert may still use the remaining information in the header
7747 to track down the originating mail user agent.
7752 suppression doesn't occur.
7756 \*(BY\*(OP If terminal capability queries are supported and this option
7757 is set then \*(UA will try to switch to the
7758 .Dq alternate screen
7759 when in interactive mode, so that the terminal will go back to the
7760 normal screen, leaving all the text there intact, when \*(UA exits.
7763 even when supported for this to produce appealing results the used
7765 and possibly configured
7766 .Va pipe-TYPE/SUBTYPE
7767 applications that take control over the terminal need to have
7768 corresponding support and must be configured accordingly, too, e.g., the
7770 pager should be driven with the
7776 If defined, gives the number of lines of a message to be printed out
7777 with the top command; normally, the first five lines are printed.
7781 The character set of the terminal \*(UA operates on,
7782 and the one and only supported character set that \*(UA can use if no
7783 character set conversion capabilities have been compiled into it,
7784 in which case it defaults to ISO-8859-1 unless it can deduce a value
7788 Refer to the section
7789 .Sx "Character sets"
7790 for the complete picture about character sets.
7793 .It Va user-HOST , user
7794 \*(IN Variable chain that sets a global fallback user name, which is
7795 used in case none has been given in the protocol and account-specific
7797 This variable defaults to the value of
7802 \*(BO Setting this option enables upward compatibility with \*(UA
7803 version 15.0 in respect to which configuration options are available and
7804 how they are handled.
7805 This manual uses \*(IN and \*(OU to refer to the new and the old way of
7806 doing things, respectively.
7810 \*(BO Setting this option, also controllable via the command line option
7812 causes \*(UA to be more verbose, e.g., it will display obsoletion
7813 warnings and SSL/TLS certificate chains.
7814 Even though marked \*(BO this option may be set twice in order to
7815 increase the level of verbosity even more, in which case even details of
7816 the actual message delivery and protocol conversations are shown.
7819 is sufficient to disable verbosity as such.
7825 .It Va version , version-major , version-minor , version-update
7826 \*(RO \*(UA version information: the first variable contains a string
7827 containing the complete version identification \(en this is identical to
7828 the output of the command
7830 The latter three contain only digits: the major, minor and update
7834 .It Va writebackedited
7835 If this variable is set messages modified using the
7839 commands are written back to the current folder when it is quit;
7840 it is only honoured for writable folders in MBOX format, though.
7841 Note that the editor will be pointed to the raw message content in that
7842 case, i.e., neither MIME decoding nor decryption will have been
7843 performed, and proper RFC 4155
7845 quoting of newly added or edited content is also left as an excercise to
7849 .\" }}} (INTERNAL VARIABLES)
7852 .\" .Sh ENVIRONMENT {{{
7856 .Dq environment variable
7857 should be considered an indication that the following variables are
7858 either standardized as being vivid parts of process environments, or
7859 are commonly found in there.
7860 The process environment is inherited from the
7862 once \*(UA is started, and unless otherwise explicitly noted variables
7863 in there integrate into the normal handling of
7864 .Sx "INTERNAL VARIABLES" ,
7865 from \*(UAs point of view, i.e., they can be
7867 as such in resource files and need not necessarily come from the process
7868 environment and be managed via
7872 E.g., the following example, applicable to a POSIX shell, sets the
7874 environment variable for \*(UA only, and beforehand exports the
7876 in order to affect any further processing in the running shell:
7878 .Bd -literal -offset indent
7879 $ EDITOR="vim -u ${HOME}/.vimrc"
7881 $ COLUMNS=80 \*(ua -R
7884 .Bl -tag -width ".It Ev _AILR_"
7887 The user's preferred width in column positions for the terminal screen
7889 Queried and used once on program startup.
7893 The name of the file to use for saving aborted messages if
7895 is set; this defaults to
7903 Pathname of the text editor to use in the
7907 .Sx "TILDE ESCAPES" .
7908 A default editor is used if this value is not defined.
7912 The user's home directory.
7913 This variable is only used when it resides in the process environment.
7916 to update the value at runtime.
7923 .It Ev LANG , LC_ALL , LC_COLLATE , LC_CTYPE , LC_MESSAGES
7927 .Sx "Character sets" .
7931 The user's preferred number of lines on a page or the vertical screen
7932 or window size in lines.
7933 Queried and used once on program startup.
7937 Pathname of the directory lister to use in the
7939 command when operating on local mailboxes.
7942 (path search through
7947 Is used as the user's mailbox, if set.
7948 Otherwise, a system-dependent default is used.
7949 Supports a logical subset of the special conventions that are documented
7958 \*(OP Overrides the default path search for
7959 .Sx "The Mailcap files" ,
7960 which is defined in the standard RFC 1524 as
7961 .Ql ~/.mailcap:\:/etc/mailcap:\:/usr/etc/mailcap:\:/usr/local/etc/mailcap .
7962 .\" TODO we should have a mailcaps-default virtual RDONLY option!
7963 (\*(UA makes it a configuration option, however.)
7964 Note this is not a search path, but a path search.
7968 Is used as a startup file instead of
7971 When \*(UA scripts are invoked on behalf of other users,
7972 this variable should be set to
7974 to avoid side-effects from reading their configuration files.
7975 This variable is only used when it resides in the process environment.
7979 The name of the user's mbox file.
7980 A logical subset of the special conventions that are documented for the
7985 The fallback default is
7990 Traditionally this secondary mailbox is used as the file to save
7991 messages from the system mailbox that have been read.
7993 .Sx "Message states" .
7996 .It Ev NAIL_NO_SYSTEM_RC
7997 If this variable is set then reading of
7999 at startup is inhibited, i.e., the same effect is achieved as if \*(UA
8000 had been started up with the option
8002 This variable is only used when it resides in the process environment.
8006 \*(IN\*(OP This variable overrides the default location of the user's
8012 The value to put into the
8014 field of the message header.
8018 Pathname of the program to use in the more command or when the
8021 The default paginator is
8023 (path search through
8028 A list of directories that is searched by the shell when looking for
8029 commands (as such only recognized in the process environment).
8033 The shell to use for the commands
8039 and when starting subprocesses.
8040 A default shell is used if this option is not defined.
8044 Changes the letters printed in the first column of a header summary.
8048 \*(OP The terminal type for which output is to be prepared.
8052 Used as directory for temporary files instead of
8055 This variable is only used when it resides in the process environment.
8058 to update the value at runtime.
8062 Force identification as the given user, i.e., identical to the
8064 command line option.
8065 This variable is only used when it resides in the process environment.
8068 to update the value at runtime, but note that doing so won't trigger any
8069 of those validation checks that were performed on program startup (again).
8073 Pathname of the text editor to use in the
8077 .Sx "TILDE ESCAPES" .
8085 .Bl -tag -width ".It Pa _etc/mime.type_"
8087 File giving initial commands.
8090 System wide initialization file.
8094 \*(OP Personal MIME type handler definition file, see
8095 .Sx "The Mailcap files" .
8096 (RFC 1524 location, the actual path is a configuration option.)
8100 \*(OP System wide MIME type handler definition file, see
8101 .Sx "The Mailcap files" .
8102 (RFC 1524 location, the actual path is a configuration option.)
8105 .It Pa ~/.mime.types
8106 Personal MIME types, see
8107 .Sx "The mime.types files" .
8110 .It Pa /etc/mime.types
8111 System wide MIME types, see
8112 .Sx "The mime.types files" .
8116 \*(IN\*(OP The default location of the users
8118 file \(en the section
8119 .Sx "The .netrc file"
8120 documents the file format.
8123 .\" .Ss "The mime.types files" {{{
8124 .Ss "The mime.types files"
8126 When sending messages \*(UA tries to determine the content type of all
8128 When displaying message content or attachments \*(UA uses the content
8129 type to decide wether it can directly display data or wether it needs to
8130 deal with content handlers.
8131 It learns about MIME types and how to treat them by reading
8133 files, the loading of which can be controlled by setting the variable
8134 .Va mimetypes-load-control .
8137 can also be used to deal with MIME types.)
8139 files have the following syntax:
8142 .Dl type/subtype extension [extension ...]
8147 are strings describing the file contents, and one or multiple
8149 s, separated by whitespace, name the part of a filename starting after
8150 the last dot (of interest).
8151 Comments may be introduced anywhere on a line with a number sign
8153 causing the remaining line to be discarded.
8155 \*(UA also supports an extended, non-portable syntax in specially
8156 crafted files, which can be loaded via the alternative value syntax of
8157 .Va mimetypes-load-control
8158 and prepends an optional
8162 .Dl [type-marker ]type/subtype extension [extension ...]
8165 The following type markers are supported:
8168 .Bl -tag -compact -offset indent -width ".It Ar _n_u"
8170 Treat message parts with this content as plain text.
8175 Treat message parts with this content as HTML tagsoup.
8176 If the \*(OPal HTML-tagsoup-to-text converter is not available treat
8177 the content as plain text instead.
8181 but instead of falling back to plain text require an explicit content
8182 handler to be defined.
8187 for sending messages:
8189 .Va mime-allow-text-controls ,
8190 .Va mimetypes-load-control .
8191 For reading etc. messages:
8192 .Sx "HTML mail and MIME attachments" ,
8193 .Sx "The Mailcap files" ,
8195 .Va mime-counter-evidence ,
8196 .Va mimetypes-load-control ,
8197 .Va pipe-TYPE/SUBTYPE ,
8198 .Va pipe-EXTENSION .
8201 .\" .Ss "The Mailcap files" {{{
8202 .Ss "The Mailcap files"
8205 .Dq User Agent Configuration Mechanism
8206 which \*(UA \*(OPally supports.
8207 It defines a file format to be used to inform mail user agent programs
8208 about the locally-installed facilities for handling various data
8209 formats, i.e., about commands and how they can be used to display, edit
8210 etc. MIME part contents, as well as a default path search that includes
8211 multiple possible locations of
8215 environment variable that can be used to overwrite that (repeating here
8216 that it is not a search path, but instead a path search specification).
8217 Any existing files will be loaded in sequence, appending any content to
8218 the list of MIME type handler directives.
8222 files consist of a set of newline separated entries.
8223 Comment lines start with a number sign
8225 (in the first column!) and are ignored.
8226 Empty lines are also ignored.
8227 All other lines form individual entries that must adhere to the syntax
8229 To extend a single entry (not comment) its line can be continued on
8230 follow lines if newline characters are
8232 by preceding them with the backslash character
8234 The standard doesn't specify how leading whitespace of follow lines is
8235 to be treated, therefore \*(UA retains it.
8239 entries consist of a number of semicolon
8241 separated fields, and the backslash
8243 character can be used to escape any following character including
8244 semicolon and itself.
8245 The first two fields are mandatory and must occur in the specified
8246 order, the remaining fields are optional and may appear in any order.
8247 Leading and trailing whitespace of content is ignored (removed).
8250 The first field defines the MIME
8252 the entry is about to handle (case-insensitively, and no backslash
8253 escaping is possible in this field).
8254 If the subtype is specified as an asterisk
8256 the entry is ment to match all subtypes of the named type, e.g.,
8258 would match any audio type.
8259 The second field defines the shell command which shall be used to
8261 MIME parts of the given type; it is implicitly called the
8268 shell commands message (MIME part) data is passed via standard input
8269 unless the given shell command includes one or more instances of the
8272 in which case these instances will be replaced with a temporary filename
8273 and the data will have been stored in the file that is being pointed to.
8276 shell commands data is assumed to be generated on standard output unless
8277 the given command includes (one ore multiple)
8279 In any case any given
8281 format is replaced with a(n already) properly quoted filename.
8282 Note that when a command makes use of a temporary file via
8284 then \*(UA will remove it again, as if the
8285 .Cd x-mailx-tmpfile ,
8286 .Cd x-mailx-tmpfile-fill
8288 .Cd x-mailx-tmpfile-unlink
8289 flags had been set; see below for more.
8292 The optional fields either define a shell command or an attribute (flag)
8293 value, the latter being a single word and the former being a keyword
8294 naming the field followed by an equals sign
8296 succeeded by a shell command, and as usual for any
8298 content any whitespace surrounding the equals sign will be removed, too.
8299 Optional fields include the following:
8302 .Bl -tag -width textualnewlines
8304 A program that can be used to compose a new body or body part in the
8311 field, but is to be used when the composing program needs to specify the
8313 header field to be applied to the composed data.
8317 A program that can be used to edit a body or body part in the given
8322 A program that can be used to print a message or body part in the given
8327 Specifies a program to be run to test some condition, e.g., the machine
8328 architecture, or the window system in use, to determine whether or not
8329 this mailcap entry applies.
8330 If the test fails, a subsequent mailcap entry should be sought; also see
8331 .Cd x-mailx-test-once .
8333 .It Cd needsterminal
8334 This flag field indicates that the given shell command must be run on
8335 an interactive terminal.
8336 \*(UA will temporarily release the terminal to the given command in
8337 interactive mode, in non-interactive mode this entry will be entirely
8338 ignored; this flag implies
8339 .Cd x-mailx-noquote .
8341 .It Cd copiousoutput
8342 A flag field which indicates that the output of the
8344 command will be an extended stream of textual output that can be
8345 (re)integrated into \*(UA's normal visual display.
8346 It is mutually exclusive with
8349 .Cd x-mailx-always .
8351 .It Cd textualnewlines
8352 A flag field which indicates that this type of data is line-oriented and
8355 all newlines should be converted to canonical form (CRLF) before
8356 encoding, and will be in that form after decoding.
8360 This field gives a file name format, in which
8362 will be replaced by a random string, the joined combination of which
8363 will be used as the filename denoted by
8364 .Ev NAIL_FILENAME_TEMPORARY .
8365 One could specify that a GIF file being passed to an image viewer should
8366 have a name ending in
8369 .Ql nametemplate=%s.gif .
8370 Note that \*(UA ignores the name template unless that solely specifies
8371 a filename suffix that consists of (ASCII) alphabetic and numeric
8372 characters, the underscore and dot only.
8375 Names a file, in X11 bitmap (xbm) format, which points to an appropriate
8376 icon to be used to visually denote the presence of this kind of data.
8377 This field is not used by \*(UA.
8380 A textual description that describes this type of data.
8382 .It Cd x-mailx-always
8383 Extension flag field that denotes that the given
8385 command shall be executed even if multiple messages will be displayed
8387 Normally messages which require external viewers that produce output
8388 which doesn't integrate into \*(UA's visual display (i.e., don't have
8390 set) have to be addressed directly and individually.
8391 (To avoid cases where, e.g., a thousand PDF viewer instances are spawned
8394 .It Cd x-mailx-even-if-not-interactive
8395 An extension flag test field \(em by default handlers without
8397 are entirely ignored in non-interactive mode, but if this flag is set
8398 then their use will be considered.
8399 It is an error if this flag is set for commands that use the flag
8402 .It Cd x-mailx-noquote
8403 An extension flag field that indicates that even a
8406 command shall not be used to generate message quotes
8407 (as it would be by default).
8409 .It Cd x-mailx-async
8410 Extension flag field that denotes that the given
8412 command shall be executed asynchronously, without blocking \*(UA.
8413 Cannot be used in conjunction with
8416 .It Cd x-mailx-test-once
8417 Extension flag which denotes wether the given
8419 command shall be evaluated once only and the (boolean) result be cached.
8420 This is handy if some global unchanging condition is to be queried, like
8421 .Dq running under the X Window System .
8423 .It Cd x-mailx-tmpfile
8424 Extension flag field that requests creation of a zero-sized temporary
8425 file, the name of which is to be placed in the environment variable
8426 .Ev NAIL_FILENAME_TEMPORARY .
8427 It is an error to use this flag with commands that include a
8431 .It Cd x-mailx-tmpfile-fill
8432 Normally the MIME part content is passed to the handler via standard
8433 input; if this flag is set then the data will instead be written into
8435 .Cd x-mailx-tmpfile .
8436 In order to cause deletion of the temporary file you will have to set
8437 .Cd x-mailx-tmpfile-unlink
8439 It is an error to use this flag with commands that include a
8443 .It Cd x-mailx-tmpfile-unlink
8444 Extension flag field that requests that the temporary file shall be
8445 deleted automatically when the command loop is entered again at latest.
8446 (Don't use this for asynchronous handlers.)
8447 It is an error to use this flag with commands that include a
8449 format, or without also setting
8452 .Cd x-mailx-tmpfile-fill .
8454 .It Cd x-mailx-tmpfile-keep
8457 implies the three tmpfile related flags above, but if you want, e.g.,
8459 and deal with the temporary file yourself, you can add in this flag to
8461 .Cd x-mailx-tmpfile-unlink .
8466 The standard includes the possibility to define any number of additional
8467 entry fields, prefixed by
8469 Flag fields apply to the entire
8471 entry \(em in some unusual cases, this may not be desirable, but
8472 differentiation can be accomplished via separate entries, taking
8473 advantage of the fact that subsequent entries are searched if an earlier
8474 one does not provide enough information.
8477 command needs to specify the
8481 command shall not, the following will help out the latter (with enabled
8485 level \*(UA will show informations about handler evaluation):
8487 .Bd -literal -offset indent
8488 application/postscript; ps-to-terminal %s; needsterminal
8489 application/postscript; ps-to-terminal %s; compose=idraw %s
8493 In fields any occurrence of the format string
8495 will be replaced by the
8498 Named parameters from the
8500 field may be placed in the command execution line using
8502 followed by the parameter name and a closing
8505 The entire parameter should appear as a single command line argument,
8506 regardless of embedded spaces; thus:
8508 .Bd -literal -offset indent
8510 Content-type: multipart/mixed; boundary=42
8513 multipart/*; /usr/local/bin/showmulti \e
8514 %t %{boundary} ; composetyped = /usr/local/bin/makemulti
8516 # Executed shell command
8517 /usr/local/bin/showmulti multipart/mixed 42
8521 .\" TODO v15: Mailcap: %n,%F
8522 Note that \*(UA doesn't support handlers for multipart MIME parts as
8523 shown in this example (as of today).
8524 \*(UA doesn't support the additional formats
8528 An example file, also showing how to properly deal with the expansion of
8530 which includes any quotes that are necessary to make it a valid shell
8531 argument by itself and thus will cause undesired behaviour when placed
8532 in additional user-provided quotes:
8534 .Bd -literal -offset indent
8536 text/richtext; richtext %s; copiousoutput
8538 text/x-perl; perl -cWT %s
8542 trap "rm -f ${infile}" EXIT\e; \e
8543 trap "exit 75" INT QUIT TERM\e; \e
8545 x-mailx-async; x-mailx-tmpfile-keep
8547 application/*; echo "This is \e"%t\e" but \e
8548 is 50 \e% Greek to me" \e; < %s head -c 1024 | cat -vET; \e
8549 copiousoutput; x-mailx-noquote
8554 .Sx "HTML mail and MIME attachments" ,
8555 .Sx "The mime.types files" ,
8558 .Va mime-counter-evidence ,
8559 .Va pipe-TYPE/SUBTYPE ,
8560 .Va pipe-EXTENSION .
8563 .\" .Ss "The .netrc file" {{{
8564 .Ss "The .netrc file"
8568 file contains user credentials for machine accounts.
8569 The default location in the user's
8571 directory may be overridden by the
8573 environment variable.
8574 The file consists of space, tabulator or newline separated tokens.
8575 \*(UA implements a parser that supports a superset of the original BSD
8576 syntax, but users should nonetheless be aware of portability glitches
8577 of that file format, shall their
8579 be usable across multiple programs and platforms:
8582 .Bl -bullet -compact
8584 BSD doesn't support single, but only double quotation marks, e.g.,
8585 .Ql password="pass with spaces" .
8587 BSD (only?) supports escaping of single characters via a backslash
8588 (e.g., a space can be escaped via
8590 in- as well as outside of a quoted string.
8592 BSD doesn't require the final quotation mark of the final user input token.
8594 At least Hewlett-Packard seems to support a format which also allows
8595 tokens to be separated with commas \(en this format is not supported!
8597 Whereas other programs may require that the
8599 file is accessible by only the user if it contains a
8605 \*(UA will always require these strict permissions.
8609 Of the following list of supported tokens \*(UA only uses (and caches)
8615 .Bl -tag -width password
8616 .It Cd machine Ar name
8617 The hostname of the entries' machine, lowercase-normalized by \*(UA
8619 Any further file content, until either end-of-file or the occurrence
8624 first-class token is bound (only related) to the machine
8627 As an extension that shouldn't be the cause of any worries
8628 \*(UA supports a single wildcard prefix for
8630 .Bd -literal -offset indent
8631 machine *.example.com login USER password PASS
8632 machine pop3.example.com login USER password PASS
8633 machine smtp.example.com login USER password PASS
8639 .Ql pop3.example.com ,
8643 .Ql local.smtp.example.com .
8644 Note that in the example neither
8645 .Ql pop3.example.com
8647 .Ql smtp.example.com
8648 will be matched by the wildcard, since the exact matches take
8649 precedence (it is however faster to specify it the other way around).
8654 except that it is a fallback entry that is used shall none of the
8655 specified machines match; only one default token may be specified,
8656 and it must be the last first-class token.
8658 .It Cd login Ar name
8659 The user name on the remote machine.
8661 .It Cd password Ar string
8662 The user's password on the remote machine.
8664 .It Cd account Ar string
8665 Supply an additional account password.
8666 This is merely for FTP purposes.
8668 .It Cd macdef Ar name
8670 A macro is defined with the specified
8672 it is formed from all lines beginning with the next line and continuing
8673 until a blank line is (consecutive newline characters are) encountered.
8676 entries cannot be utilized by multiple machines, too, but must be
8677 defined following the
8679 they are intended to be used with.)
8682 exists, it is automatically run as the last step of the login process.
8683 This is merely for FTP purposes.
8690 .\" .Sh EXAMPLES {{{
8693 .\" .Ss "An example configuration" {{{
8694 .Ss "An example configuration"
8696 .Bd -literal -offset indent
8697 # This example assumes v15.0 compatibility mode
8700 # Where are the up-to-date SSL certificates?
8701 #set ssl-ca-dir=/etc/ssl/certs
8702 set ssl-ca-file=/etc/ssl/certs/ca-certificates.crt
8704 # (Since we manage up-to-date ones explicitly, don't use any,
8705 # possibly outdated, default certificates shipped with OpenSSL
8706 set ssl-no-default-ca
8708 # Don't use protocols older than TLS v1.2.
8709 # Change this only when the remote server doesn't support it:
8710 # maybe use ssl-protocol-HOST (or -USER@HOST) syntax to define
8711 # such explicit exceptions, then
8712 set ssl-protocol="-ALL,+TLSv1.2"
8714 # Explicitly define the list of ciphers, which may improve security,
8715 # especially with protocols older than TLS v1.2. See ciphers(1).
8716 # Hint: it is important to include "@STRENGTH": only with it the
8717 # final list will be sorted by algorithm strength.
8718 # This is an example: in reality it is possibly best to only use
8719 # ssl-cipher-list-HOST (or -USER@HOST), as necessary, again..
8720 set ssl-cipher-list="ALL:!aNULL:!MEDIUM:!LOW:\e
8721 !MD5:!RC4:!EXPORT:@STRENGTH"
8723 # Request strict transport security checks!
8724 set ssl-verify=strict
8726 # Essential setting: select allowed character sets
8727 set sendcharsets=utf-8,iso-8859-1
8729 # A very kind option: when replying to a message, first try to
8730 # use the same encoding that the original poster used herself!
8731 set reply-in-same-charset
8733 # When replying to or forwarding a message the comment and name
8734 # parts of email addresses are removed unless this variable is set
8737 # When sending messages, wait until the Mail-Transfer-Agent finishs.
8738 # Only like this you'll be able to see errors reported through the
8739 # exit status of the MTA (including the builtin SMTP one)!
8742 # Only use builtin MIME types, no mime.types(5) files
8743 set mimetypes-load-control
8745 # Default directory where we act in (relative to $HOME)
8747 # A leading "+" (often) means: under *folder*
8748 # *record* is used to save copies of sent messages
8749 set MBOX=+mbox.mbox record=+sent.mbox DEAD=+dead.mbox
8751 # Make "file mymbox" and "file myrec" go to..
8752 shortcut mymbox %:+mbox.mbox myrec +sent.mbox
8754 # Not really optional, e.g., for S/MIME
8755 set from="Your Name <youremail@domain>"
8757 # It may be necessary to set hostname and/or smtp-hostname
8758 # if the "SERVER" of smtp and "domain" of from don't match.
8759 # The `urlencode' command can be used to encode USER and PASS
8760 set smtp=(smtp[s]/submission)://[USER[:PASS]@]SERVER[:PORT] \e
8761 smtp-auth=login/plain... \e
8764 # Never refuse to start into interactive mode, and more
8766 colour-pager crt= \e
8767 followup-to followup-to-honour=ask-yes \e
8768 history-file=+.\*(uahist history-size=-1 history-gabby \e
8769 mime-counter-evidence=0xE \e
8770 prompt="\e033[31m?\e?[\e$ \e@]\e& \e033[0m" \e
8771 reply-to-honour=ask-yes
8773 # When `p'rinting messages, show only these headers
8774 # (use `P'rint for all headers and `S'how for raw message)
8775 retain date from to cc subject
8777 # Some mailing lists
8778 mlist @xyz-editor.xyz$ @xyzf.xyz$
8779 mlsubscribe ^xfans@xfans.xyz$
8781 # A real life example of a very huge free mail provider
8784 set from="Your Name <youremail@domain>"
8785 # (The plain smtp:// proto is optional)
8786 set smtp=USER:PASS@smtp.gmXil.com smtp-use-starttls
8789 # Here is a pretty large one which does not allow sending mails
8790 # if there is a domain name mismatch on the SMTP protocol level,
8791 # which would bite us if the value of from does not match, e.g.,
8792 # for people who have a sXXXXeforge project and want to speak
8793 # with the mailing list under their project account (in from),
8794 # still sending the message through their normal mail provider
8797 set from="Your Name <youremail@domain>"
8798 set smtp=smtps://USER:PASS@smtp.yaXXex.ru:465 \e
8799 hostname=yaXXex.com smtp-hostname=
8802 # Create some new commands so that, e.g., `ls /tmp' will..
8813 ghost llS !ls -aFlrS
8816 # We don't support gpg(1) directly yet. But simple --clearsign'd
8817 # message parts can be dealt with as follows:
8820 set pipe-text/plain="@*#++=@\e
8821 < \e"${NAIL_FILENAME_TEMPORARY}\e" awk \e
8822 -v TMPFILE=\e"${NAIL_FILENAME_TEMPORARY}\e" '\e
8824 /^-----BEGIN PGP SIGNED MESSAGE-----/,/^$/ {\e
8827 print \e"--- GPG --verify ---\e";\e
8828 system(\e"gpg --verify \e" TMPFILE \e" 2>&1\e");\e
8829 print \e"--- GPG --verify ---\e";\e
8833 /^-----BEGIN PGP SIGNATURE-----/,\e
8834 /^-----END PGP SIGNATURE-----/ {\e
8844 !printf 'Key IDs to gpg --recv-keys: ';\e
8846 gpg --recv-keys ${keyids};
8852 When storing passwords in
8854 appropriate permissions should be set on this file with
8855 .Ql $ chmod 0600 \*(ur .
8858 is available user credentials can be stored in the central
8860 file instead; e.g., here is a different version of the example account
8861 that sets up SMTP and POP3:
8863 .Bd -literal -offset indent
8866 set from="Your Name <youremail@domain>"
8868 #set agent-shell-lookup="gpg -d .pass.gpg"
8870 set smtp=smtps://smtp.yXXXXx.ru:465 \e
8871 smtp-hostname= hostname=yXXXXx.com
8872 set pop3-keepalive=240 pop3-no-apop-pop.yXXXXx.ru
8873 ghost xp fi pop3s://pop.yXXXXx.ru
8882 .Bd -literal -offset indent
8883 machine *.yXXXXx.ru login USER password PASS
8888 .Va agent-shell-lookup
8889 is available things could be diversified further by using encrypted
8890 password storage: for this, don't specify
8894 file and instead uncomment the line that defines agent lookup in the
8897 above, then create the encrypted password storage file
8900 .Bd -literal -offset indent
8903 $ eval `gpg-agent --daemon \e
8904 --pinentry-program=/usr/bin/pinentry-curses \e
8905 --max-cache-ttl 99999 --default-cache-ttl 99999`
8909 This configuration should now work just fine (use the
8911 command line option for a(n almost) dry-run):
8914 .Dl $ echo text | \*(ua -vv -AXandeX -s Subject some@where
8917 .\" .Ss "Signed and encrypted messages with S/MIME" {{{
8918 .Ss "Signed and encrypted messages with S/MIME"
8920 \*(OP S/MIME provides two central mechanisms:
8921 message signing and message encryption.
8922 A signed message contains some data in addition to the regular text.
8923 The data can be used to verify that the message was sent using a valid
8924 certificate, that the sender's address in the message header matches
8925 that in the certificate, and that the message text has not been altered.
8926 Signing a message does not change its regular text;
8927 it can be read regardless of whether the recipient's software is able to
8931 It is thus usually possible to sign all outgoing messages if so desired.
8932 Encryption, in contrast, makes the message text invisible for all people
8933 except those who have access to the secret decryption key.
8934 To encrypt a message, the specific recipient's public encryption key
8936 It is therefore not possible to send encrypted mail to people unless their
8937 key has been retrieved from either previous communication or public key
8939 A message should always be signed before it is encrypted.
8940 Otherwise, it is still possible that the encrypted message text is
8944 A central concept to S/MIME is that of the certification authority (CA).
8945 A CA is a trusted institution that issues certificates.
8946 For each of these certificates it can be verified that it really
8947 originates from the CA, provided that the CA's own certificate is
8949 A set of CA certificates is usually delivered with OpenSSL and installed
8951 If you trust the source of your OpenSSL software installation,
8952 this offers reasonable security for S/MIME on the Internet.
8954 .Va ssl-no-default-ca
8958 .Va smime-ca-dir . )
8959 In general, a certificate cannot be more secure than the method its CA
8960 certificate has been retrieved with, though.
8961 Thus if you download a CA certificate from the Internet,
8962 you can only trust the messages you verify using that certificate as
8963 much as you trust the download process.
8966 The first thing you need for participating in S/MIME message exchange is
8967 your personal certificate, including a private key.
8968 The certificate contains public information, in particular your name and
8969 your email address(es), and the public key that is used by others to
8970 encrypt messages for you,
8971 and to verify signed messages they supposedly received from you.
8972 The certificate is included in each signed message you send.
8973 The private key must be kept secret.
8974 It is used to decrypt messages that were previously encrypted with your
8975 public key, and to sign messages.
8978 For personal use it is recommended that you get a S/MIME certificate
8979 from one of the major CAs on the Internet using your WWW browser.
8980 Many CAs offer such certificates for free.
8982 .Lk https://www.CAcert.org
8983 which issues client and server certificates to members of their
8984 community for free; their root certificate
8985 .Pf ( Lk https://\:www.cacert.org/\:certs/\:root.crt )
8986 is often not in the default set of trusted CA root certificates, though,
8987 which means you will have to download their root certificate separately
8988 and ensure it is part of our S/MIME certificate validation chain by
8991 or as a vivid member of the
8993 But let's take a step-by-step tour on how to setup S/MIME with
8994 a certificate from CAcert.org despite this situation!
8997 First of all you will have to become a member of the CAcert.org
8998 community, simply by registrating yourself via the web interface.
8999 Once you are, create and verify all email addresses you want to be able
9000 to create signed and encrypted messages for/with using the corresponding
9001 entries of the web interface.
9002 Now ready to create S/MIME certificates, so let's create a new
9003 .Dq client certificate ,
9004 ensure to include all email addresses that should be covered by the
9005 certificate in the following web form, and also to use your name as the
9009 Create a private key and a certificate request on your local computer
9010 (please see the manual pages of the used commands for more in-depth
9011 knowledge on what the used arguments etc. do):
9014 .Dl openssl req -nodes -newkey rsa:4096 -keyout key.pem -out creq.pem
9017 Afterwards copy-and-paste the content of
9019 into the certificate-request (CSR) field of the web form on the
9020 CAcert.org website (you may need to unfold some
9021 .Dq advanced options
9022 to see the corresponding text field).
9023 This last step will ensure that your private key (which never left your
9024 box) and the certificate belong together (through the public key that
9025 will find its way into the certificate via the certificate-request).
9026 You are now ready and can create your CAcert certified certificate.
9027 Download and store or copy-and-paste it as
9032 In order to use your new S/MIME setup you will have to create
9033 a combined private key/public key (certificate) file:
9036 .Dl cat key.pem pub.crt > ME@HERE.com.paired
9039 This is the file \*(UA will work with.
9040 If you have created your private key with a passphrase then \*(UA will
9041 ask you for it whenever a message is signed or decrypted.
9042 Set the following variables to henceforth use S/MIME (setting
9044 is of interest for verification only):
9046 .Bd -literal -offset indent
9047 set smime-ca-file=ALL-TRUSTED-ROOT-CERTS-HERE \e
9048 smime-sign-cert=ME@HERE.com.paired \e
9049 smime-sign-message-digest=SHA256 \e
9054 From each signed message you send, the recipient can fetch your
9055 certificate and use it to send encrypted mail back to you.
9056 Accordingly if somebody sends you a signed message, you can do the same,
9059 command to check the validity of the certificate.
9062 Variables of interest for S/MIME signing:
9066 .Va smime-crl-file ,
9067 .Va smime-no-default-ca ,
9069 .Va smime-sign-cert ,
9070 .Va smime-sign-include-certs
9072 .Va smime-sign-message-digest .
9075 After it has been verified save the certificate via
9077 and tell \*(UA that it should use it for encryption for further
9078 communication with that somebody:
9080 .Bd -literal -offset indent
9082 set smime-encrypt-USER@HOST=FILENAME \e
9083 smime-cipher-USER@HOST=AES256
9087 Additional variables of interest for S/MIME en- and decryption:
9090 .Va smime-encrypt-USER@HOST .
9093 You should carefully consider if you prefer to store encrypted messages
9095 If you do, anybody who has access to your mail folders can read them,
9096 but if you do not, you might be unable to read them yourself later if
9097 you happen to lose your private key.
9100 command saves messages in decrypted form, while the
9104 commands leave them encrypted.
9107 Note that neither S/MIME signing nor encryption applies to message
9108 subjects or other header fields yet.
9109 Thus they may not contain sensitive information for encrypted messages,
9110 and cannot be trusted even if the message content has been verified.
9111 When sending signed messages,
9112 it is recommended to repeat any important header information in the
9116 .\" .Ss "Using CRLs with S/MIME or SSL/TLS" {{{
9117 .Ss "Using CRLs with S/MIME or SSL/TLS"
9119 \*(OP Certification authorities (CAs) issue certificate revocation
9120 lists (CRLs) on a regular basis.
9121 These lists contain the serial numbers of certificates that have been
9122 declared invalid after they have been issued.
9123 Such usually happens because the private key for the certificate has
9125 because the owner of the certificate has left the organization that is
9126 mentioned in the certificate, etc.
9127 To seriously use S/MIME or SSL/TLS verification,
9128 an up-to-date CRL is required for each trusted CA.
9129 There is otherwise no method to distinguish between valid and
9130 invalidated certificates.
9131 \*(UA currently offers no mechanism to fetch CRLs, nor to access them on
9132 the Internet, so you have to retrieve them by some external mechanism.
9135 \*(UA accepts CRLs in PEM format only;
9136 CRLs in DER format must be converted, like, e.\|g.:
9139 .Dl $ openssl crl \-inform DER \-in crl.der \-out crl.pem
9142 To tell \*(UA about the CRLs, a directory that contains all CRL files
9143 (and no other files) must be created.
9148 variables, respectively, must then be set to point to that directory.
9149 After that, \*(UA requires a CRL to be present for each CA that is used
9150 to verify a certificate.
9153 .\" .Ss "Handling spam" {{{
9156 \*(OP \*(UA can make use of several spam interfaces for the purpose of
9157 identification of, and, in general, dealing with spam messages.
9158 A precondition of most commands in order to function is that the
9160 variable is set to one of the supported interfaces.
9161 Once messages have been identified as spam their (volatile)
9163 state can be prompted: the
9167 message specifications will address respective messages and their
9169 entries will be used when displaying the
9171 in the header display.
9176 rates the given messages and sets their
9179 If the spam interface offers spam scores those can also be displayed in
9180 the header display by including the
9190 will interact with the Bayesian filter of the chosen interface and learn
9191 the given messages as
9195 respectively; the last command can be used to cause
9197 of messages; it adheres to their current
9199 state and thus reverts previous teachings.
9204 will simply set and clear, respectively, the mentioned volatile
9206 message flag, without any interface interaction.
9213 .Va spam-interface Ns s
9217 require a running instance of the
9219 server in order to function, started with the option
9221 shall Bayesian filter learning be possible.
9223 only works via a local path-based
9225 socket, but otherwise the following will be equivalently fine:
9227 .Bd -literal -offset indent
9228 $ spamd -i localhost:2142 -i /tmp/.spamsock -d [-L] [-l]
9229 $ spamd --listen=localhost:2142 --listen=/tmp/.spamsock \e
9230 --daemonize [--local] [--allow-tell]
9234 Thereafter \*(UA can make use of these interfaces:
9236 .Bd -literal -offset indent
9237 $ \*(ua -Sspam-interface=spamd -Sspam-maxsize=500000 \e
9238 -Sspamd-socket=/tmp/.spamsock -Sspamd-user=
9240 $ \*(ua -Sspam-interface=spamc -Sspam-maxsize=500000 \e
9241 -Sspamc-command=/usr/local/bin/spamc \e
9242 -Sspamc-arguments="-U /tmp/.spamsock" -Sspamc-user=
9244 $ \*(ua -Sspam-interface=spamc -Sspam-maxsize=500000 \e
9245 -Sspamc-command=/usr/local/bin/spamc \e
9246 -Sspamc-arguments="-d localhost -p 2142" -Sspamc-user=
9250 Using the generic filter approach allows usage of programs like
9254 Here is an example for the former, requiring it to be accessible via
9257 .Bd -literal -offset indent
9258 $ \*(ua -Sspam-interface=filter -Sspam-maxsize=500000 \e
9259 -Sspamfilter-ham="bogofilter -n" \e
9260 -Sspamfilter-noham="bogofilter -N" \e
9261 -Sspamfilter-nospam="bogofilter -S" \e
9262 -Sspamfilter-rate="bogofilter -TTu 2>/dev/null" \e
9263 -Sspamfilter-spam="bogofilter -s" \e
9264 -Sspamfilter-rate-scanscore="1;^(.+)$"
9268 Because messages must exist on local storage in order to be scored (or
9269 used for Bayesian filter training), it is possibly a good idea to
9270 perform the local spam check last:
9272 .Bd -literal -offset indent
9273 define spamdelhook {
9275 spamset (header x-dcc-brand-metrics "bulk")
9276 # Server-side spamassassin(1)
9277 spamset (header x-spam-flag "YES")
9278 del :s # TODO we HAVE to be able to do `spamrate :u ! :sS'
9284 set folder-hook-FOLDER=spamdelhook
9288 See also the documentation for the variables
9289 .Va spam-interface , spam-maxsize ,
9290 .Va spamc-command , spamc-arguments , spamc-user ,
9291 .Va spamd-socket , spamd-user ,
9292 .Va spamfilter-ham , spamfilter-noham , spamfilter-nospam , \
9295 .Va spamfilter-rate-scanscore .
9303 .\" .Ss "\*(UA shortly hangs on startup" {{{
9304 .Ss "\*(UA shortly hangs on startup"
9306 This can have two reasons, one is the necessity to wait for a file lock
9307 and can't be helped, the other being that \*(UA calls the function
9309 in order to query the nodename of the box (sometimes the real one is
9310 needed instead of the one represented by the internal variable
9312 You may have varying success by ensuring that the real hostname and
9316 or, more generally, that the name service is properly setup \(en
9319 return what you'd expect?
9320 Does this local hostname has a domain suffix?
9321 RFC 6762 standardized the link-local top-level domain
9325 .\" .Ss "I can't login to Google mail a.k.a. GMail" {{{
9326 .Ss "I can't login to Google mail a.k.a. GMail"
9328 Since 2014 some free service providers classify programs as
9330 unless they use a special authentification method (OAuth 2.0) which
9331 wasn't standardized for non-HTTP protocol authentication token query
9332 until August 2015 (RFC 7628).
9335 Different to Kerberos / GSSAPI, which is developed since the mid of the
9336 1980s, where a user can easily create a local authentication ticket for
9337 her- and himself with the locally installed
9339 program, that protocol has no such local part but instead requires
9340 a world-wide-web query to create or fetch a token; since there is no
9341 local cache this query has to be performed whenever \*(UA is invoked
9342 from the command line (in interactive sessions situation may differ).
9345 \*(UA doesn't support OAuth.
9346 Because of this it is necessary to declare \*(UA a
9348 (on the providers account web page) in order to read and send mail.
9349 However, it also seems possible to take the following steps instead:
9354 give the provider the number of a mobile phone,
9357 .Dq 2-Step Verification ,
9359 create an application specific password (16 characters), and
9361 use that special password instead of your real Google account password in
9362 S-nail (for more on that see the section
9363 .Sx "On URL syntax and credential lookup" ) .
9369 .\" .Sh "SEE ALSO" {{{
9387 .Xr spamassassin 1 ,
9412 M. Douglas McIlroy writes in his article
9413 .Dq A Research UNIX Reader: Annotated Excerpts \
9414 from the Programmer's Manual, 1971-1986
9417 command already appeared in First Edition
9421 .Bd -ragged -offset indent
9422 Electronic mail was there from the start.
9423 Never satisfied with its exact behavior, everybody touched it at one
9424 time or another: to assure the safety of simultaneous access, to improve
9425 privacy, to survive crashes, to exploit uucp, to screen out foreign
9426 freeloaders, or whatever.
9427 Not until v7 did the interface change (Thompson).
9428 Later, as mail became global in its reach, Dave Presotto took charge and
9429 brought order to communications with a grab-bag of external networks
9435 Mail was written in 1978 by Kurt Shoens and developed as part of the
9438 distribution until 1995.
9439 Mail has then seen further development in open source
9441 variants, noticeably by Christos Zoulas in
9443 Basing upon this Nail, later Heirloom Mailx, was developed by Gunnar
9444 Ritter in the years 2000 until 2008.
9445 Since 2012 S-nail is maintained by Steffen (Daode) Nurpmeso.
9446 This man page is derived from
9447 .Dq The Mail Reference Manual
9448 that was originally written by Kurt Shoens.
9455 .An "Christos Zoulas" ,
9456 .An "Gunnar Ritter" ,
9457 .An "Steffen Nurpmeso" Aq Mt s-nail-users@lists.sourceforge.net
9459 .Mt s-mailx@sdaoden.eu ) .
9465 The character set conversion uses and relies upon the
9468 Its functionality differs widely between the various system environments
9472 Limitations with IMAP mailboxes are:
9473 It is not possible to edit messages, but it is possible to append them.
9474 Thus to edit a message, create a local copy of it, edit it, append it,
9475 and delete the original.
9476 The line count for the header display is only appropriate if the entire
9477 message has been downloaded from the server.
9478 The marking of messages as `new' is performed by the IMAP server;
9483 will not cause it to be reset, and if the
9485 variable is unset, messages that arrived during a session will not be
9486 in state `new' anymore when the folder is opened again.
9487 Also if commands queued in disconnected mode are committed,
9488 the IMAP server will delete the `new' flag for all messages in the
9490 and new messages will appear as unread when it is selected for viewing
9492 The `flagged', `answered', and `draft' attributes are usually permanent,
9493 but some IMAP servers are known to drop them without notification.
9494 Message numbers may change with IMAP every time before the prompt is
9495 printed if \*(UA is notified by the server that messages have been
9496 deleted by some other client or process.
9497 In this case, `Expunged n messages' is printed, and message numbers may
9501 Limitations with POP3 mailboxes are:
9502 It is not possible to edit messages, they can only be copied and deleted.
9503 The line count for the header display is only appropriate if the entire
9504 message has been downloaded from the server.
9505 The status field of a message is maintained by the server between
9506 connections; some servers do not update it at all, and with a server
9509 command will not cause the message status to be reset.
9514 variable have no effect.
9515 It is not possible to rename or to remove POP3 mailboxes.
9522 is typed while an IMAP or POP3 operation is in progress, \*(UA will wait
9523 until the operation can be safely aborted, and will then return to the
9524 command loop and print the prompt again.
9527 is typed while \*(UA is waiting for the operation to complete, the
9528 operation itself will be cancelled.
9529 In this case, data that has not been fetched yet will have to be fetched
9530 before the next command can be performed.
9531 If the cancelled operation was using an SSL/TLS encrypted channel,
9532 an error in the SSL transport will very likely result and render the
9533 connection unusable.
9536 As \*(UA is a mail user agent, it provides only basic SMTP services.
9537 If it fails to contact its upstream SMTP server, it will not make
9538 further attempts to transfer the message at a later time,
9539 and it does not leave other information about this condition than an
9540 error message on the terminal and an entry in
9542 This is usually not a problem if the SMTP server is located in the same
9543 local network as the computer on which \*(UA is run.
9544 However, care should be taken when using a remote server of an ISP;
9545 it might be better to set up a local SMTP server then which just acts as
9549 \*(UA immediately contacts the SMTP server (or
9551 ) even when operating in
9554 It would not make much sense for \*(UA to defer outgoing mail since SMTP
9555 servers usually provide much more elaborated delay handling than \*(UA
9556 could perform as a client.
9557 Thus the recommended setup for sending mail in
9559 mode is to configure a local SMTP server such that it sends outgoing
9560 mail as soon as an external network connection is available again,
9561 i.e., to advise it to do that from a network startup script.
9567 With IMAP, at least if the IMAP cache is used, if multiple
9571 cycles happen without an intervening change of the active mailbox then
9572 \*(UA will at some time loose the ability to keep the local state
9573 up-to-date, meaning that, e.g., messages show up with false numbers, and
9574 including the possibility that messages are accessed via numbers that
9575 are no(t longer) valid, resulting in program crashes.
9576 The solution is to change the active mailbox before that happens :).
9579 from the distribution or the repository.
9581 After deleting some message of a POP3 mailbox the header summary falsely
9582 claims that there are no messages to display, you need to perform
9583 a scroll or dot movement to restore proper state.
9585 In threaded display a power user may encounter crashes very
9586 occasionally (this is may and very).