Provided by: heirloom-mailx_12.5-2+deb7u1build0.14.04.1_amd64 
NAME
mailx - send and receive Internet mail
SYNOPSIS
mailx [-BDdEFintv~] [-s subject] [-a attachment ] [-c cc-addr] [-b bcc-addr] [-r from-
addr] [-h hops] [-A account] [-S variable[=value]] to-addr . . .
mailx [-BDdeEHiInNRv~] [-T name] [-A account] [-S variable[=value]] -f [name]
mailx [-BDdeEinNRv~] [-A account] [-S variable[=value]] [-u user]
DESCRIPTION
Mailx is an intelligent mail processing system, which has a command syntax reminiscent of
ed(1) with lines replaced by messages. It is based on Berkeley Mail 8.1, is intended to
provide the functionality of the POSIX mailx command, and offers extensions for MIME,
IMAP, POP3, SMTP, and S/MIME. Mailx provides enhanced features for interactive use, such
as caching and disconnected operation for IMAP, message threading, scoring, and filtering.
It is also usable as a mail batch language, both for sending and receiving mail.
The following options are accepted:
-A name
Executes an account command (see below) for name after the startup files have been
read.
-a file
Attach the given file to the message.
-B Make standard input and standard output line-buffered.
-b address
Send blind carbon copies to list. List should be a comma-separated list of names.
-c address
Send carbon copies to list of users.
-D Start in disconnected mode; see the description for the disconnected variable
option.
-d Enables debugging messages and disables the actual delivery of messages. Unlike
-v, this option is intended for mailx development only.
-e Just check if mail is present in the system mailbox. If yes, return an exit status
of zero, else, a non-zero value.
-E If an outgoing message does not contain any text in its first or only message part,
do not send it but discard it silently, effectively setting the skipemptybody
variable at program startup. This is useful for sending messages from scripts
started by cron(8).
-f [file]
Read in the contents of the user's mbox (or the specified file) for processing;
when mailx is quit, it writes undeleted messages back to this file. The string
file is handled as described for the folder command below.
-F Save the message to send in a file named after the local part of the first
recipient's address.
-H Print header summaries for all messages and exit.
-h hops
Invoke sendmail with the specified hop count. This option has no effect when SMTP
is used for sending mail.
-i Ignore tty interrupt signals. This is particularly useful when using mailx on
noisy phone lines.
-I Shows the `Newsgroup:' or `Article-Id:' fields in the header summary. Only
applicable in combination with -f.
-n Inhibits reading /etc/nail.rc upon startup. This option should be activated for
mailx scripts that are invoked on more than one machine, because the contents of
that file may differ between them.
-N Inhibits the initial display of message headers when reading mail or editing a mail
folder.
-q file
Start the message with the contents of the specified file. May be given in send
mode only.
-r address
Sets the From address. Overrides any from variable specified in environment or
startup files. Tilde escapes are disabled. The -r address options are passed to
the mail transfer agent unless SMTP is used. This option exists for compatibility
only; it is recommended to set the from variable directly instead.
-R Opens any folders read-only.
-s subject
Specify subject on command line (only the first argument after the -s flag is used
as a subject; be careful to quote subjects containing spaces).
-S variable[=value]
Sets the internal option variable and, in case of a string option, assigns value to
it.
-T name
Writes the `Message-Id:' and `Article-Id:' header fields of each message read in
the file name. Implies -I. Compressed files are handled as described for the
folder command below.
-t The message to be sent is expected to contain a message header with `To:', `Cc:',
or `Bcc:' fields giving its recipients. Recipients specified on the command line
are ignored.
-u user
Reads the mailbox of the given user name.
-v Verbose mode. The details of delivery are displayed on the user's terminal.
-V Print mailx's version and exit.
-~ Enable tilde escapes even if not in interactive mode.
Sending mail
To send a message to one or more people, mailx can be invoked with arguments which are the
names of people to whom the mail will be sent. The user is then expected to type in his
message, followed by an `control-D' at the beginning of a line. The section below
Replying to or originating mail, describes some features of mailx available to help when
composing letters.
Reading mail
In normal usage mailx is given no arguments and checks the user's mail out of the post
office, then prints out a one line header of each message found. The current message is
initially the first message (numbered 1) and can be printed using the print command which
can be abbreviated `p'). The user can move among the messages much as he moves between
lines in ed(1), with the commands `+' and `-' moving backwards and forwards, and simple
numbers.
Disposing of mail
After examining a message the user can delete `d') the message or reply `r') to it.
Deletion causes the mailx program to forget about the message. This is not irreversible;
the message can be undeleted `u') by giving its number, or the mailx session can be
aborted by giving the exit `x') command. Deleted messages will, however, usually
disappear never to be seen again.
Specifying messages
Commands such as print and delete can be given a list of message numbers as arguments to
apply to a number of messages at once. Thus `delete 1 2' deletes messages 1 and 2, while
`delete 1-5' deletes messages 1 through 5. In sorted or threaded mode (see the sort and
thread commands), `delete 1-5' deletes the messages that are located between (and
including) messages 1 through 5 in the sorted/threaded order, as shown in the header
summary. The following special message names exist:
:n All new messages.
:o All old messages (any not in state read or new).
:u All unread messages.
:d All deleted messages (for the undelete command).
:r All read messages.
:f All `flagged' messages.
:a All answered messages (cf. the markanswered variable).
:t All messages marked as draft.
:k All `killed' messages.
:j All messages classified as junk.
. The current message.
; The message that was previously the current message.
, The parent message of the current message, that is the message with the Message-ID
given in the `In-Reply-To:' field or the last entry of the `References:' field of
the current message.
- The next previous undeleted message, or the next previous deleted message for the
undelete command. In sorted/threaded mode, the next previous such message in the
sorted/threaded order.
+ The next undeleted message, or the next deleted message for the undelete command.
In sorted/threaded mode, the next such message in the sorted/threaded order.
^ The first undeleted message, or the first deleted message for the undelete command.
In sorted/threaded mode, the first such message in the sorted/threaded order.
$ The last message. In sorted/threaded mode, the last message in the sorted/threaded
order.
&x In threaded mode, selects the message addressed with x, where x is any other
message specification, and all messages from the thread that begins at it.
Otherwise, it is identical to x. If x is omitted, the thread beginning with the
current message is selected.
* All messages.
` All messages that were included in the message list for the previous command.
/string
All messages that contain string in the subject field (case ignored). See also the
searchheaders variable. If string is empty, the string from the previous
specification of that type is used again.
address
All messages from address. By default, this is a case-sensitive search for the
complete email address. If the allnet variable is set, only the local part of the
addresses is evaluated for the comparison. Otherwise if the showname variable is
set, a case-sensitive search for the complete real name of a sender is performed.
The IMAP-style (from address) expression can be used instead if substring matches
are desired.
(criterion)
All messages that satisfy the given IMAP-style SEARCH criterion. This addressing
mode is available with all types of folders; for folders not located on IMAP
servers, or for servers unable to execute the SEARCH command, mailx will perform
the search locally. Strings must be enclosed by double quotes `"' in their
entirety if they contain white space or parentheses; within the quotes, only
backslash `\' is recognized as an escape character. All string searches are case-
insensitive. When the description indicates that the `envelope' representation of
an address field is used, this means that the search string is checked against both
a list constructed as
("real name" "source-route" "local-part" "domain-part")
for each address, and the addresses without real names from the respective header
field. Criteria can be nested using parentheses.
(criterion1 criterion2 ... criterionN)
All messages that satisfy all of the given criteria.
(or criterion1 criterion2)
All messages that satisfy either criterion1 or criterion2, or both. To connect
more than two criteria using `or', (or) specifications have to be nested using
additional parentheses, as with `(or a (or b c))'; `(or a b c)' means ((a or b) and
c). For a simple `or' operation of independent criteria on the lowest nesting
level, it is possible to achieve similar effects by using three separate criteria,
as with `(a) (b) (c)'.
(not criterion)
All messages that do not satisfy criterion.
(bcc string)
All messages that contain string in the `envelope' representation of the Bcc:
field.
(cc string)
All messages that contain string in the `envelope' representation of the Cc: field.
(from string)
All messages that contain string in the `envelope' representation of the From:
field.
(subject string)
All messages that contain string in the Subject: field.
(to string)
All messages that contain string in the `envelope' representation of the To: field.
(header name string)
All messages that contain string in the specified Name: field.
(body string)
All messages that contain string in their body.
(text string)
All messages that contain string in their header or body.
(larger size)
All messages that are larger than size (in bytes).
(smaller size)
All messages that are smaller than size (in bytes).
(before date)
All messages that were received before date; date must be in the form d[d]-mon-
yyyy, where d[d] is the day of the month as one or two digits, mon is the name of
the month—one of `Jan', `Feb', `Mar', `Apr', `May', `Jun', `Jul', `Aug', `Sep',
`Oct', `Nov', or `Dec', and yyyy is the year as four digits; e.g. "30-Aug-2004".
(on date)
All messages that were received on the specified date.
(since date)
All messages that were received since the specified date.
(sentbefore date)
All messages that were sent on the specified date.
(senton date)
All messages that were sent on the specified date.
(sentsince date)
All messages that were sent since the specified date.
() The same criterion as for the previous search. This specification cannot be used
as part of another criterion. If the previous command line contained more than one
independent criterion, the last of those criteria is used.
A practical method to read a set of messages is to issue a from command with the search
criteria first to check for appropriate messages, and to read each single message then by
typing ``' repeatedly.
Replying to or originating mail
The reply command can be used to set up a response to a message, sending it back to the
person who it was from. Text the user types in then, up to an end-of-file, defines the
contents of the message. While the user is composing a message, mailx treats lines
beginning with the character `~' specially. For instance, typing `~m' (alone on a line)
will place a copy of the current message into the response right shifting it by a tabstop
(see indentprefix variable, below). Other escapes will set up subject fields, add and
delete recipients to the message, attach files to it and allow the user to escape to an
editor to revise the message or to a shell to run some commands. (These options are given
in the summary below.)
Ending a mail processing session
The user can end a mailx session with the quit (`q') command. Messages which have been
examined go to the user's mbox file unless they have been deleted in which case they are
discarded. Unexamined messages go back to the post office. (See the -f option above).
Personal and systemwide distribution lists
It is also possible to create a personal distribution lists so that, for instance, the
user can send mail to `cohorts' and have it go to a group of people. Such lists can be
defined by placing a line like
alias cohorts bill ozalp jkf mark kridle@ucbcory
in the file .mailrc in the user's home directory. The current list of such aliases can be
displayed with the alias command in mailx. System wide distribution lists can be created
by editing /etc/aliases, see aliases(5) and sendmail(8); these are kept in a different
syntax. In mail the user sends, personal aliases will be expanded in mail sent to others
so that they will be able to reply to the recipients. System wide aliases are not
expanded when the mail is sent, but any reply returned to the machine will have the system
wide alias expanded as all mail goes through sendmail.
Recipient address specifications
If the expandaddr option is not set (the default), recipient addresses must be names of
local mailboxes or Internet mail addresses.
If the expandaddr option is set, the following rules apply: When an address is used to
name a recipient (in any of To, Cc, or Bcc), names of local mail folders and pipes to
external commands can also be specified; the message text is then written to them. The
rules are: Any name which starts with a `|' character specifies a pipe, the command string
following the `|' is executed and the message is sent to its standard input; any other
name which contains a `@' character is treated as a mail address; any other name which
starts with a `+' character specifies a folder name; any other name which contains a `/'
character but no `!' or `%' character before also specifies a folder name; what remains
is treated as a mail address. Compressed folders are handled as described for the folder
command below.
Network mail (Internet / ARPA, UUCP, Berknet)
See mailaddr(7) for a description of network addresses. Mailx has a number of options
which can be set in the .mailrc file to alter its behavior; thus `set askcc' enables the
askcc feature. (These options are summarized below).
MIME types
For any outgoing attachment, mailx tries to determine the content type. It does this by
reading MIME type files whose lines have the following syntax:
type/subtype extension [extension . . .]
where type/subtype are strings describing the file contents, and extension is the part of
a filename starting after the last dot. Any line not immediately beginning with an ASCII
alphabetical character is ignored by mailx. If there is a match with the extension of the
file to attach, the given type/subtype pair is used. Otherwise, or if the filename has no
extension, the content types text/plain or application/octet-stream are used, the first
for text or international text files, the second for any file that contains formatting
characters other than newlines and horizontal tabulators.
Character sets
Mailx normally detects the character set of the terminal using the LC_CTYPE locale
setting. If the locale cannot be used appropriately, the ttycharset variable should be
set to provide an explicit value. When reading messages, their text is converted to the
terminal character set if possible. Unprintable characters and illegal byte sequences are
detected and replaced by Unicode substitute characters or question marks unless the print-
all-chars is set at initialization time.
The character set for outgoing messages is not necessarily the same as the one used on the
terminal. If an outgoing text message contains characters not representable in US-ASCII,
the character set being used must be declared within its header. Permissible values can
be declared using the sendcharsets variable, separated by commas; mailx tries each of the
values in order and uses the first appropriate one. If the message contains characters
that cannot be represented in any of the given character sets, the message will not be
sent, and its text will be saved to the `dead.letter' file. Messages that contain NUL
bytes are not converted.
Outgoing attachments are converted if they are plain text. If the sendcharsets variable
contains more than one character set name, the ~@ tilde escape will ask for the character
sets for individual attachments if it is invoked without arguments.
Best results are usually achieved when mailx is run in a UTF-8 locale on a UTF-8 capable
terminal. In this setup, characters from various countries can be displayed, while it is
still possible to use more simple character sets for sending to retain maximum
compatibility with older mail clients.
Commands
Each command is typed on a line by itself, and may take arguments following the command
word. The command need not be typed in its entirety – the first command which matches the
typed prefix is used. For commands which take message lists as arguments, if no message
list is given, then the next message forward which satisfies the command's requirements is
used. If there are no messages forward of the current message, the search proceeds
backwards, and if there are no good messages at all, mailx types `applicable messages' and
aborts the command. If the command begins with a # sign, the line is ignored.
The arguments to commands can be quoted, using the following methods:
• An argument can be enclosed between paired double-quotes "" or single-quotes '';
any white space, shell word expansion, or backslash characters within the quotes
are treated literally as part of the argument. A double-quote will be treated
literally within single-quotes and vice versa. These special properties of the
quote marks occur only when they are paired at the beginning and end of the
argument.
• A backslash outside of the enclosing quotes is discarded and the following
character is treated literally as part of the argument.
• An unquoted backslash at the end of a command line is discarded and the next line
continues the command.
Filenames, where expected, are subjected to the following transformations, in sequence:
• If the filename begins with an unquoted plus sign, and the folder variable is
defined, the plus sign will be replaced by the value of the folder variable
followed by a slash. If the folder variable is unset or is set to null, the
filename will be unchanged.
• Shell word expansions are applied to the filename. If more than a single pathname
results from this expansion and the command is expecting one file, an error
results.
The following commands are provided:
- Print out the preceding message. If given a numeric argument n, goes to the n'th
previous message and prints it.
? Prints a brief summary of commands.
! Executes the shell (see sh(1) and csh(1)) command which follows.
| A synonym for the pipe command.
account
(ac) Creates, selects or lists an email account. An account is formed by a group
of commands, primarily of those to set variables. With two arguments, of which the
second is a `{', the first argument gives an account name, and the following lines
create a group of commands for that account until a line containing a single `}'
appears. With one argument, the previously created group of commands for the
account name is executed, and a folder command is executed for the system mailbox
or inbox of that account. Without arguments, the list of accounts and their
contents are printed. As an example,
account myisp {
set folder=imaps://mylogin@imap.myisp.example
set record=+Sent
set from="myname@myisp.example (My Name)"
set smtp=smtp.myisp.example
}
creates an account named `myisp' which can later be selected by specifying `account
myisp'.
alias (a) With no arguments, prints out all currently-defined aliases. With one
argument, prints out that alias. With more than one argument, creates a new alias
or changes an old one.
alternates
(alt) The alternates command is useful if the user has accounts on several
machines. It can be used to inform mailx that the listed addresses all belong to
the invoking user. When he replies to messages, mailx will not send a copy of the
message to any of the addresses listed on the alternates list. If the alternates
command is given with no argument, the current set of alternate names is displayed.
answered
(ans) Takes a message list and marks each message as a having been answered. This
mark has no technical meaning in the mail system; it just causes messages to be
marked in the header summary, and makes them specially addressable.
cache Only applicable to cached IMAP mailboxes; takes a message list and reads the
specified messages into the IMAP cache.
call Calls a macro (see the define command).
cd Same as chdir.
certsave
Only applicable to S/MIME signed messages. Takes a message list and a file name
and saves the certificates contained within the message signatures to the named
file in both human-readable and PEM format. The certificates can later be used to
send encrypted messages to the messages' originators by setting the smime-encrypt-
user@host variable.
chdir (ch) Changes the user's working directory to that specified, if given. If no
directory is given, then changes to the user's login directory.
classify
(cl) Takes a list of messages and examines their contents for characteristics of
junk mail using Bayesian filtering. Messages considered to be junk are then marked
as such. The junk mail database is not changed.
collapse
(coll) Only applicable to threaded mode. Takes a message list and makes all
replies to these messages invisible in header summaries, unless they are in state
`new'.
connect
(conn) If operating in disconnected mode on an IMAP mailbox, switch to online mode
and connect to the mail server while retaining the mailbox status. See the
description of the disconnected variable for more information.
copy (c) The copy command does the same thing that save does, except that it does not
mark the messages it is used on for deletion when the user quits. Compressed files
and IMAP mailboxes are handled as described for the folder command.
Copy (C) Similar to copy, but saves the messages in a file named after the local part of
the sender address of the first message.
decrypt
(dec) For unencrypted messages, this command is identical to copy. Encrypted
messages are first decrypted, if possible, and then copied.
Decrypt
(Dec) Similar to decrypt, but saves the messages in a file named after the local
part of the sender address of the first message.
define (def) Defines a macro. A macro definition is a sequence of commands in the
following form:
define name {
command1
command2
...
commandN
}
Once defined, a macro can be explicitly invoked using the call command, or can be
implicitly invoked by setting the folder-hook or folder-hook-fullname variables.
defines
Prints the currently defined macros including their contents.
delete (d) Takes a list of messages as argument and marks them all as deleted. Deleted
messages will not be saved in mbox, nor will they be available for most other
commands.
discard
Same as ignore.
disconnect
(disco) If operating in online mode on an IMAP mailbox, switch to disconnected mode
while retaining the mailbox status. See the description of the disconnected
variable for more information. A list of messages may optionally be given as
argument; the respective messages are then read into the cache before the
connection is closed. Thus `disco *' makes the entire current mailbox available
for disconnected use.
dp or dt
Deletes the current message and prints the next message. If there is no next
message, mailx says `at EOF'.
draft Takes a message list and marks each message as a draft. This mark has no technical
meaning in the mail system; it just causes messages to be marked in the header
summary, and makes them specially addressable.
echo Echoes its arguments, resolving special names as documented for the folder command.
The escape sequences `\a', `\b', `\c', `\f', `\n', `\r', `\t', `\v', `\\', and
`\0num' are interpreted as with the echo(1) command.
edit (e) Takes a list of messages and points the text editor at each one in turn.
Modified contents are discarded unless the writebackedited variable is set.
else Marks the end of the then-part of an if statement and the beginning of the part to
take effect if the condition of the if statement is false.
endif Marks the end of an if statement.
exit (ex or x) Effects an immediate return to the Shell without modifying the user's
system mailbox, his mbox file, or his edit file in -f.
file (fi) The same as folder.
flag (fl) Takes a message list and marks the messages as `flagged' for urgent/special
attention. This mark has no technical meaning in the mail system; it just causes
messages to be highlighted in the header summary, and makes them specially
addressable.
folders
With no arguments, list the names of the folders in the folder directory. With an
existing folder as an argument, lists then names of folders below the named folder;
e.g. the command `folders @' lists the folders on the base level of the current
IMAP server. See also the imap-list-depth variable.
folder (fold) The folder command switches to a new mail file or folder. With no
arguments, it tells the user which file he is currently reading. If an argument is
given, it will write out changes (such as deletions) the user has made in the
current file and read in the new file. Some special conventions are recognized for
the name. # means the previous file, % means the invoking user's system mailbox,
%user means user's system mailbox, & means the invoking user's mbox file, and +file
means a file in the folder directory. %:filespec expands to the same value as
filespec, but the file is handled as a system mailbox e. g. by the mbox and save
commands. If the name matches one of the strings defined with the shortcut
command, it is replaced by its long form and expanded. If the name ends with .gz
or .bz2, it is treated as compressed with gzip(1) or bzip2(1), respectively.
Likewise, if name does not exist, but either name.gz or name.bz2 exists, the
compressed file is used. If name refers to a directory with the subdirectories
`tmp', `new', and `cur', it is treated as a folder in maildir format. A name of
the form
protocol://[user@]host[:port][/file]
is taken as an Internet mailbox specification. The supported protocols are
currently imap (IMAP v4r1), imaps (IMAP with SSL/TLS encryption), pop3 (POP3), and
pop3s (POP3 with SSL/TLS encryption). If user contains special characters, in
particular `/' or `%', they must be escaped in URL notation, as `%2F' or `%25'.
The optional file part applies to IMAP only; if it is omitted, the default `INBOX'
is used. If mailx is connected to an IMAP server, a name of the form @mailbox
refers to the mailbox on that server. If the `folder' variable refers to an IMAP
account, the special name `%' selects the `INBOX' on that account.
Followup
(F) Similar to Respond, but saves the message in a file named after the local part
of the first recipient's address.
followup
(fo) Similar to respond, but saves the message in a file named after the local part
of the first recipient's address.
followupall
Similar to followup, but responds to all recipients regardless of the flipr and
Replyall variables.
followupsender
Similar to Followup, but responds to the sender only regardless of the flipr and
Replyall variables.
forward
(fwd) Takes a message and the address of a recipient and forwards the message to
him. The text of the original message is included in the new one, with the value
of the fwdheading variable printed before. The fwdignore and fwdretain commands
specify which header fields are included in the new message. Only the first part
of a multipart message is included unless the forward-as-attachment option is set.
Forward
(Fwd) Similar to forward, but saves the message in a file named after the local
part of the recipient's address.
from (f) Takes a list of messages and prints their message headers, piped through the
pager if the output does not fit on the screen.
fwdignore
Specifies which header fields are to be ignored with the forward command. This
command has no effect when the forward-as-attachment option is set.
fwdretain
Specifies which header fields are to be retained with the forward command.
fwdretain overrides fwdignore. This command has no effect when the forward-as-
attachment option is set.
good (go) Takes a list of messages and marks all of them as not being junk mail. Data
from these messages is then inserted into the junk mail database for future
classification.
headers
(h) Lists the current range of headers, which is an 18-message group. If a `+'
argument is given, then the next 18-message group is printed, and if a `-' argument
is given, the previous 18-message group is printed.
help A synonym for ?.
hold (ho, also preserve) Takes a message list and marks each message therein to be saved
in the user's system mailbox instead of in mbox. Does not override the delete
command. mailx deviates from the POSIX standard with this command, as a `next'
command issued after `hold' will display the following message, not the current
one.
if Commands in mailx's startup files can be executed conditionally depending on
whether the user is sending or receiving mail with the if command. For example:
if receive
commands . . .
endif
An else form is also available:
if receive
commands . . .
else
commands . . .
endif
Note that the only allowed conditions are receive, send, and term (execute command
if standard input is a tty).
ignore Add the list of header fields named to the ignored list. Header fields in the
ignore list are not printed on the terminal when a message is printed. This
command is very handy for suppression of certain machine-generated header fields.
The Type and Print commands can be used to print a message in its entirety,
including ignored fields. If ignore is executed with no arguments, it lists the
current set of ignored fields.
imap Sends command strings directly to the current IMAP server. Mailx operates always
in IMAP selected state on the current mailbox; commands that change this will
produce undesirable results and should be avoided. Useful IMAP commands are:
create Takes the name of an IMAP mailbox as an argument and creates it.
getquotaroot
Takes the name of an IMAP mailbox as an argument and prints the quotas that
apply to the mailbox. Not all IMAP servers support this command.
namespace
Takes no arguments and prints the Personal Namespaces, the Other User's
Namespaces, and the Shared Namespaces. Each namespace type is printed in
parentheses; if there are multiple namespaces of the same type, inner
parentheses separate them. For each namespace, a namespace prefix and a
hierarchy separator is listed. Not all IMAP servers support this command.
inc Same as newmail.
junk (j) Takes a list of messages and marks all of them as junk mail. Data from these
messages is then inserted into the junk mail database for future classification.
kill (k) Takes a list of messages and `kills' them. Killed messages are not printed in
header summaries, and are ignored by the next command. The kill command also sets
the score of the messages to negative infinity, so that subsequent score commands
will not unkill them again. Killing is only effective for the current session on a
folder; when it is quit, all messages are automatically unkilled.
list Prints the names of all available commands.
Mail (M) Similar to mail, but saves the message in a file named after the local part of
the first recipient's address.
mail (m) Takes as argument login names and distribution group names and sends mail to
those people.
mbox Indicate that a list of messages be sent to mbox in the user's home directory when
mailx is quit. This is the default action for messages if unless the hold option
is set. mailx deviates from the POSIX standard with this command, as a `next'
command issued after `mbox' will display the following message, not the current
one.
move (mv) Acts like copy, but marks the messages for deletion if they were transferred
successfully.
Move (Mv) Similar to move, but moves the messages to a file named after the local part
of the sender address of the first message.
newmail
Checks for new mail in the current folder without committing any changes before.
If new mail is present, a message is printed. If the header variable is set, the
headers of each new message are also printed.
next (n) like + or CR) Goes to the next message in sequence and types it. With an
argument list, types the next matching message.
New Same as unread.
new Same as unread.
online Same as connect.
noop If the current folder is located on an IMAP or POP3 server, a NOOP command is sent.
Otherwise, no operation is performed.
Pipe (Pi) Like pipe but also pipes ignored header fields and all parts of MIME
multipart/alternative messages.
pipe (pi) Takes a message list and a shell command and pipes the messages through the
command. Without an argument, the current message is piped through the command
given by the cmd variable. If the page variable is set, every message is followed
by a formfeed character.
preserve
(pre) A synonym for hold.
Print (P) Like print but also prints out ignored header fields and all parts of MIME
multipart/alternative messages. See also print, ignore, and retain.
print (p) Takes a message list and types out each message on the user's terminal. If the
message is a MIME multipart message, all parts with a content type of `text' or
`message' are shown, the other are hidden except for their headers. Messages are
decrypted and converted to the terminal character set if necessary.
probability
(prob) For each word given as argument, the contents of its junk mail database
entry are printed.
quit (q) Terminates the session, saving all undeleted, unsaved messages in the user's
mbox file in his login directory, preserving all messages marked with hold or
preserve or never referenced in his system mailbox, and removing all other messages
from his system mailbox. If new mail has arrived during the session, the message
`You have new mail' is given. If given while editing a mailbox file with the -f
flag, then the edit file is rewritten. A return to the Shell is effected, unless
the rewrite of edit file fails, in which case the user can escape with the exit
command.
redirect
(red) Same as resend.
Redirect
(Red) Same as Resend.
remove (rem) Removes the named folders. The user is asked for confirmation in interactive
mode.
rename (ren) Takes the name of an existing folder and the name for the new folder and
renames the first to the second one. Both folders must be of the same type and
must be located on the current server for IMAP.
Reply (R) Reply to originator. Does not reply to other recipients of the original
message.
reply (r) Takes a message list and sends mail to the sender and all recipients of the
specified message. The default message must not be deleted.
replyall
Similar to reply, but responds to all recipients regardless of the flipr and
Replyall variables.
replysender
Similar to Reply, but responds to the sender only regardless of the flipr and
Replyall variables.
Resend Like resend, but does not add any header lines. This is not a way to hide the
sender's identity, but useful for sending a message again to the same recipients.
resend Takes a list of messages and a user name and sends each message to the named user.
`Resent-From:' and related header fields are prepended to the new copy of the
message.
Respond
Same as Reply.
respond
Same as reply.
respondall
Same as replyall.
respondsender
Same as replysender.
retain Add the list of header fields named to the retained list. Only the header fields
in the retain list are shown on the terminal when a message is printed. All other
header fields are suppressed. The Type and Print commands can be used to print a
message in its entirety. If retain is executed with no arguments, it lists the
current set of retained fields.
Save (S) Similar to save, but saves the messages in a file named after the local part of
the sender of the first message instead of taking a filename argument.
save (s) Takes a message list and a filename and appends each message in turn to the end
of the file. If no filename is given, the mbox file is used. The filename in
quotes, followed by the line count and character count is echoed on the user's
terminal. If editing a system mailbox, the messages are marked for deletion.
Compressed files and IMAP mailboxes are handled as described for the -f command
line option above.
savediscard
Same as saveignore.
saveignore
Saveignore is to save what ignore is to print and type. Header fields thus marked
are filtered out when saving a message by save or when automatically saving to
mbox. This command should only be applied to header fields that do not contain
information needed to decode the message, as MIME content fields do. If saving
messages on an IMAP account, ignoring fields makes it impossible to copy the data
directly on the server, thus operation usually becomes much slower.
saveretain
Saveretain is to save what retain is to print and type. Header fields thus marked
are the only ones saved with a message when saving by save or when automatically
saving to mbox. Saveretain overrides saveignore. The use of this command is
strongly discouraged since it may strip header fields that are needed to decode the
message correctly.
score (sc) Takes a message list and a floating point number and adds the number to the
score of each given message. All messages start at score 0 when a folder is
opened. When the score of a message becomes negative, it is `killed' with the
effects described for the kill command; otherwise if it was negative before and
becomes positive, it is `unkilled'. Scores only refer to the currently opened
instance of a folder.
set (se) With no arguments, prints all variable values, piped through the pager if the
output does not fit on the screen. Otherwise, sets option. Arguments are of the
form option=value (no space before or after =) or option. Quotation marks may be
placed around any part of the assignment statement to quote blanks or tabs, i.e.
`set indentprefix="->"'. If an argument begins with no, as in `set nosave', the
effect is the same as invoking the unset command with the remaining part of the
variable (`unset save').
seen Takes a message list and marks all messages as having been read.
shell (sh) Invokes an interactive version of the shell.
shortcut
Defines a shortcut name and its string for expansion, as described for the folder
command. With no arguments, a list of defined shortcuts is printed.
show (Sh) Like print, but performs neither MIME decoding nor decryption so that the raw
message text is shown.
size Takes a message list and prints out the size in characters of each message.
sort Create a sorted representation of the current folder, and change the next command
and the addressing modes such that they refer to messages in the sorted order.
Message numbers are the same as in regular mode. If the header variable is set, a
header summary in the new order is also printed. Possible sorting criteria are:
date Sort the messages by their `Date:' field, that is by the time they were
sent.
from Sort messages by the value of their `From:' field, that is by the address of
the sender. If the showname variable is set, the sender's real name (if
any) is used.
size Sort the messages by their size.
score Sort the messages by their score.
status Sort the messages by their message status (new, read, old, etc.).
subject
Sort the messages by their subject.
thread Create a threaded order, as with the thread command.
to Sort messages by the value of their `To:' field, that is by the address of
the recipient. If the showname variable is set, the recipient's real name
(if any) is used.
If no argument is given, the current sorting criterion is printed.
source The source command reads commands from a file.
thread (th) Create a threaded representation of the current folder, i.e. indent messages
that are replies to other messages in the header display, and change the next
command and the addressing modes such that they refer to messages in the threaded
order. Message numbers are the same as in unthreaded mode. If the header variable
is set, a header summary in threaded order is also printed.
top Takes a message list and prints the top few lines of each. The number of lines
printed is controlled by the variable toplines and defaults to five.
touch Takes a message list and marks the messages for saving in the mbox file. mailx
deviates from the POSIX standard with this command, as a `next' command issued
after `mbox' will display the following message, not the current one.
Type (T) Identical to the Print command.
type (t) A synonym for print.
unalias
Takes a list of names defined by alias commands and discards the remembered groups
of users. The group names no longer have any significance.
unanswered
Takes a message list and marks each message as not having been answered.
uncollapse
(unc) Only applicable to threaded mode. Takes a message list and makes the message
and all replies to it visible in header summaries again. When a message becomes
the current message, it is automatically made visible. Also when a message with
collapsed replies is printed, all of these are automatically uncollapsed.
undef Undefines each of the named macros. It is not an error to use a name that does not
belong to one of the currently defined macros.
undelete
(u) Takes a message list and marks each message as not being deleted.
undraft
Takes a message list and marks each message as a draft.
unflag Takes a message list and marks each message as not being `flagged'.
unfwdignore
Removes the header field names from the list of ignored fields for the forward
command.
unfwdretain
Removes the header field names from the list of retained fields for the forward
command.
ungood Takes a message list and undoes the effect of a good command that was previously
applied on exactly these messages.
unignore
Removes the header field names from the list of ignored fields.
unjunk Takes a message list and undoes the effect of a junk command that was previously
applied on exactly these messages.
unkill Takes a message list and `unkills' each message. Also sets the score of the
messages to 0.
Unread Same as unread.
unread (U) Takes a message list and marks each message as not having been read.
unretain
Removes the header field names from the list of retained fields.
unsaveignore
Removes the header field names from the list of ignored fields for saving.
unsaveretain
Removes the header field names from the list of retained fields for saving.
unset Takes a list of option names and discards their remembered values; the inverse of
set.
unshortcut
Deletes the shortcut names given as arguments.
unsort Disable sorted or threaded mode (see the sort and thread commands), return to
normal message order and, if the header variable is set, print a header summary.
unthread
(unth) Same as unsort.
verify (verif) Takes a message list and verifies each message. If a message is not an
S/MIME signed message, verification will fail for it. The verification process
checks if the message was signed using a valid certificate, if the message sender's
email address matches one of those contained within the certificate, and if the
message content has been altered.
visual (v) Takes a message list and invokes the display editor on each message. Modified
contents are discarded unless the writebackedited variable is set.
write (w) For conventional messages, the body without all headers is written. The output
is decrypted and converted to its native format, if necessary. If the output file
exists, the text is appended.—If a message is in MIME multipart format, its first
part is written to the specified file as for conventional messages, and the user is
asked for a filename to save each other part; if the contents of the first part are
not to be saved, `write /dev/null' can be used. For the second and subsequent
parts, if the filename given starts with a `|' character, the part is piped through
the remainder of the filename interpreted as a shell command. In non-interactive
mode, only the parts of the multipart message that have a filename given in the
part header are written, the other are discarded. The original message is never
marked for deletion in the originating mail folder. For attachments, the contents
of the destination file are overwritten if the file previously existed. No special
handling of compressed files is performed.
xit (x) A synonym for exit.
z Mailx presents message headers in windowfuls as described under the headers
command. The z command scrolls to the next window of messages. If an argument is
given, it specifies the window to use. A number prefixed by `+' or `-' indicates
that the window is calculated in relation to the current position. A number
without a prefix specifies an absolute window number, and a `$' lets mailx scroll
to the last window of messages.
Z Similar to z, but scrolls to the next or previous window that contains at least one
new or `flagged' message.
Tilde escapes
Here is a summary of the tilde escapes, which are used when composing messages to perform
special functions. Tilde escapes are only recognized at the beginning of lines. The name
`tilde escape' is somewhat of a misnomer since the actual escape character can be set by
the option escape.
~!command
Execute the indicated shell command, then return to the message.
~. Same effect as typing the end-of-file character.
~<filename
Identical to ~r.
~<!command
Command is executed using the shell. Its standard output is inserted into the
message.
~@ [filename . . . ]
With no arguments, edit the attachment list. First, the user can edit all existing
attachment data. If an attachment's file name is left empty, that attachment is
deleted from the list. When the end of the attachment list is reached, mailx will
ask for further attachments, until an empty file name is given. If filename
arguments are specified, all of them are appended to the end of the attachment
list. Filenames which contain white space can only be specified with the first
method (no filename arguments).
~A Inserts the string contained in the Sign variable (same as `~i Sign'). The escape
sequences `\t' (tabulator) and `\n' (newline) are understood.
~a Inserts the string contained in the sign variable (same as `~i sign'). The escape
sequences `\t' (tabulator) and `\n' (newline) are understood.
~bname . . .
Add the given names to the list of carbon copy recipients but do not make the names
visible in the Cc: line (`blind' carbon copy).
~cname . . .
Add the given names to the list of carbon copy recipients.
~d Read the file `dead.letter' from the user's home directory into the message.
~e Invoke the text editor on the message collected so far. After the editing session
is finished, the user may continue appending text to the message.
~fmessages
Read the named messages into the message being sent. If no messages are specified,
read in the current message. Message headers currently being ignored (by the
ignore or retain command) are not included. For MIME multipart messages, only the
first printable part is included.
~Fmessages
Identical to ~f, except all message headers and all MIME parts are included.
~h Edit the message header fields `To:', `Cc:', `Bcc:', and `Subject:' by typing each
one in turn and allowing the user to append text to the end or modify the field by
using the current terminal erase and kill characters.
~H Edit the message header fields `From:', `Reply-To:', `Sender:', and `Organization:'
in the same manner as described for ~h. The default values for these fields
originate from the from, replyto, and ORGANIZATION variables. If this tilde
command has been used, changing the variables has no effect on the current message
anymore.
~ivariable
Insert the value of the specified variable into the message adding a newline
character at the end. If the variable is unset or empty, the message remains
unaltered. The escape sequences `\t' (tabulator) and `\n' (newline) are
understood.
~mmessages
Read the named messages into the message being sent, indented by a tab or by the
value of indentprefix. If no messages are specified, read the current message.
Message headers currently being ignored (by the ignore or retain command) are not
included. For MIME multipart messages, only the first printable part is included.
~Mmessages
Identical to ~m, except all message headers and all MIME parts are included.
~p Print out the message collected so far, prefaced by the message header fields and
followed by the attachment list, if any. If the message text is longer than the
screen size, it is piped through the pager.
~q Abort the message being sent, copying the message to `dead.letter' in the user's
home directory if save is set.
~rfilename
Read the named file into the message.
~sstring
Cause the named string to become the current subject field.
~tname . . .
Add the given names to the direct recipient list.
~v Invoke an alternate editor (defined by the VISUAL option) on the message collected
so far. Usually, the alternate editor will be a screen editor. After the editor
is quit, the user may resume appending text to the end of the message.
~wfilename
Write the message onto the named file. If the file exists, the message is appended
to it.
~x Same as ~q, except that the message is not saved to the `dead.letter' file.
~|command
Pipe the message through the command as a filter. If the command gives no output
or terminates abnormally, retain the original text of the message. The command
fmt(1) is often used as command to rejustify the message.
~:mailx-command
Execute the given mailx command. Not all commands, however, are allowed.
~_mailx-command
Identical to ~:.
~~string
Insert the string of text in the message prefaced by a single ~. If the escape
character has been changed, that character must be doubled in order to send it at
the beginning of a line.
Variable options
Options are controlled via set and unset commands, see their entries for a syntax
description. An option is also set if it is passed to mailx as part of the environment
(this is not restricted to specific variables as in the POSIX standard). A value given in
a startup file overrides a value imported from the environment. Options may be either
binary, in which case it is only significant to see whether they are set or not; or
string, in which case the actual value is of interest.
Binary options
The binary options include the following:
allnet Causes only the local part to be evaluated when comparing addresses.
append Causes messages saved in mbox to be appended to the end rather than prepended.
This should always be set.
ask or asksub
Causes mailx to prompt for the subject of each message sent. If the user responds
with simply a newline, no subject field will be sent.
askatend
Causes the prompts for `Cc:' and `Bcc:' lists to appear after the message has been
edited.
askattach
If set, mailx asks for files to attach at the end of each message. Responding with
a newline indicates not to include an attachment.
askcc Causes the user to be prompted for additional carbon copy recipients (at the end of
each message if askatend or bsdcompat is set). Responding with a newline indicates
the user's satisfaction with the current list.
askbcc Causes the user to be prompted for additional blind carbon copy recipients (at the
end of each message if askatend or bsdcompat is set). Responding with a newline
indicates the user's satisfaction with the current list.
asksign
Causes the user to be prompted if the message is to be signed at the end of each
message. The smime-sign variable is ignored when this variable is set.
autocollapse
Causes threads to be collapsed automatically when threaded mode is entered (see the
collapse command).
autoinc
Same as newmail.
autoprint
Causes the delete command to behave like dp - thus, after deleting a message, the
next one will be typed automatically.
autothread
Causes threaded mode (see the thread command) to be entered automatically when a
folder is opened.
bang Enables the substitution of `!' by the contents of the last command line in shell
escapes.
bsdannounce
Causes automatic display of a header summary after executing a folder command.
bsdcompat
Sets some cosmetical features to traditional BSD style; has the same affect as
setting `askatend' and all other variables prefixed with `bsd', setting prompt to
`& ', and changing the default pager to more.
bsdflags
Changes the letters printed in the first column of a header summary to traditional
BSD style.
bsdheadline
Changes the display of columns in a header summary to traditional BSD style.
bsdmsgs
Changes some informational messages to traditional BSD style.
bsdorder
Causes the `Subject:' field to appear immediately after the `To:' field in message
headers and with the ~h tilde command.
bsdset Changes the output format of the set command to traditional BSD style.
chained-junk-tokens
Normally, the Bayesian junk mail filter bases its classifications on single word
tokens extracted from messages. If this option is set, adjacent words are combined
to pairs, which are then used as additional tokens. This usually improves the
accuracy of the filter, but also increases the junk mail database five- to tenfold.
datefield
The date in a header summary is normally the date of the mailbox `From ' line of
the message. If this variable is set, the date as given in the `Date:' header
field is used, converted to local time.
debug Prints debugging messages and disables the actual delivery of messages. Unlike
verbose, this option is intended for mailx development only.
disconnected
When an IMAP mailbox is selected and this variable is set, no connection to the
server is initiated. Instead, data is obtained from the local cache (see imap-
cache). Mailboxes that are not present in the cache and messages that have not yet
entirely been fetched from the server are not available; to fetch all messages in a
mailbox at once, the command `copy * /dev/null' can be used while still in online
mode. Changes that are made to IMAP mailboxes in disconnected mode are queued and
committed later when a connection to that server is opened in online mode. This
procedure is not completely reliable since it cannot be guaranteed that the IMAP
unique identifiers (UIDs) on the server still match the ones in the cache at that
time. Data is saved to `dead.letter' when this problem occurs.
disconnected-user@host
The specified account is handled as described for the disconnected variable above,
but other accounts are not affected.
dot The binary option dot causes mailx to interpret a period alone on a line as the
terminator of a message the user is sending.
editheaders
When a message is edited while being composed, its header is included in the
editable text. `To:', `Cc:', `Bcc:', `Subject:', `From:', `Reply-To:', `Sender:',
and 'Organization:' fields are accepted within the header, other fields are
ignored.
emptybox
If set, an empty mailbox file is not removed. This may improve the
interoperability with other mail user agents when using a common folder directory.
emptystart
If the mailbox is empty, mailx normally prints `No mail for user' and exits
immediately. If this option is set, mailx starts even with an empty mailbox.
expandaddr
Causes mailx to expand message recipient addresses, as explained in the section,
Recipient address specifications.
flipr Exchanges the Respond with the respond commands and vice-versa.
forward-as-attachment
Original messages are normally sent as inline text with the forward command, and
only the first part of a multipart message is included. With this option, messages
are sent as MIME message/rfc822 attachments, and all of their parts are included.
The fwdignore and fwdretain options are ignored when the forward-as-attachment
option is set.
fullnames
When replying to a message, mailx normally removes the comment parts of email
addresses, which by convention contain the full names of the recipients. If this
variable is set, such stripping is not performed, and comments are retained.
header Causes the header summary to be written at startup and after commands that affect
the number of messages or the order of messages in the current folder; enabled by
default.
hold This option is used to hold messages in the system mailbox by default.
ignore Causes interrupt signals from the terminal to be ignored and echoed as @'s.
ignoreeof
An option related to dot is ignoreeof which makes mailx refuse to accept a control-
d as the end of a message. Ignoreeof also applies to mailx command mode.
imap-use-starttls
Causes mailx to issue a STARTTLS command to make an unencrypted IMAP session
SSL/TLS encrypted. This functionality is not supported by all servers, and is not
used if the session is already encrypted by the IMAPS method.
imap-use-starttls-user@host
Activates imap-use-starttls for a specific account.
keep This option causes mailx to truncate the user's system mailbox instead of deleting
it when it is empty. This should always be set, since it prevents malicious users
from creating fake mail folders in a world-writable spool directory.
keepsave
When a message is saved, it is usually discarded from the originating folder when
mailx is quit. Setting this option causes all saved message to be retained.
markanswered
When a message is replied to and this variable is set, it is marked as having been
answered. This mark has no technical meaning in the mail system; it just causes
messages to be marked in the header summary, and makes them specially addressable.
metoo Usually, when a group is expanded that contains the sender, the sender is removed
from the expansion. Setting this option causes the sender to be included in the
group.
newmail
Checks for new mail in the current folder each time the prompt is printed. For
IMAP mailboxes, the server is then polled for new mail, which may result in delayed
operation if the connection to the server is slow. A maildir folder must be re-
scanned to determine if new mail has arrived.
If this variable is set to the special value nopoll, an IMAP server is not actively
asked for new mail, but new mail may still be detected and announced with any other
IMAP command that is sent to the server. A maildir folder is not scanned then.
In any case, the IMAP server may send notifications about messages that have been
deleted on the server by another process or client. In this case, `Expunged n
messages' is printed regardless of this variable, and message numbers may have
changed.
noheader
Setting the option noheader is the same as giving the -N flag on the command line.
outfolder
Causes the filename given in the record variable and the sender-based filenames for
the Copy and Save commands to be interpreted relative to the directory given in the
folder variable rather than to the current directory unless it is an absolute
pathname.
page If set, each message the pipe command prints out is followed by a formfeed
character.
piperaw
Send messages to the pipe command without performing MIME and character set
conversions.
pop3-use-apop
If this variable is set, the APOP authentication method is used when a connection
to a POP3 server is initiated. The advantage of this method over the usual
USER/PASS authentication is that the password is not sent over the network in clear
text. The connection fails if the server does not support the APOP command.
pop3-use-apop-user@host
Enables pop3-use-apop for a specific account.
pop3-use-starttls
Causes mailx to issue a STLS command to make an unencrypted POP3 session SSL/TLS
encrypted. This functionality is not supported by all servers, and is not used if
the session is already encrypted by the POP3S method.
pop3-use-starttls-user@host
Activates pop3-use-starttls for a specific account.
print-all-chars
This option causes all characters to be considered printable. It is only effective
if given in a startup file. With this option set, some character sequences in
messages may put the user's terminal in an undefined state when printed; it should
only be used as a last resort if no working system locale can be found.
print-alternatives
When a MIME message part of type multipart/alternative is displayed and it contains
a subpart of type text/plain, other parts are normally discarded. Setting this
variable causes all subparts to be displayed, just as if the surrounding part was
of type multipart/mixed.
quiet Suppresses the printing of the version when first invoked.
record-resent
If both this variable and the record variable are set, the resend and Resend
commands save messages to the record folder as it is normally only done for newly
composed messages.
reply-in-same-charset
If this variable is set, mailx first tries to use the same character set of the
original message for replies. If this fails, the sendcharsets variable is
evaluated as usual.
Replyall
Reverses the sense of reply and Reply commands.
save When the user aborts a message with two RUBOUT (interrupt characters) mailx copies
the partial letter to the file `dead.letter' in the home directory. This option is
set by default.
searchheaders
If this option is set, then a message-list specifier in the form `/x:y' will expand
to all messages containing the substring `y' in the header field `x'. The string
search is case insensitive.
sendwait
When sending a message, wait until the mail transfer agent exits before accepting
further commands. If the mail transfer agent returns a non-zero exit status, the
exit status of mailx will also be non-zero.
showlast
Setting this option causes mailx to start at the last message instead of the first
one when opening a mail folder.
showname
Causes mailx to use the sender's real name instead of the plain address in the
header field summary and in message specifications.
showto Causes the recipient of the message to be shown in the header summary if the
message was sent by the user.
skipemptybody
If an outgoing message does not contain any text in its first or only message part,
do not send it but discard it silently (see also the -E option).
smime-force-encryption
Causes mailx to refuse sending unencrypted messages.
smime-sign
If this variable is set, outgoing messages are S/MIME signed with the user's
private key. Signing a message enables a recipient to verify that the sender used
a valid certificate, that the email addresses in the certificate match those in the
message header, and that the message content has not been altered. It does not
change the message text, and people will be able to read the message as usual.
smime-no-default-ca
Do not load the default CA locations when verifying S/MIME signed messages. Only
applicable if S/MIME support is built using OpenSSL.
smtp-use-starttls
Causes mailx to issue a STARTTLS command to make an SMTP session SSL/TLS encrypted.
Not all servers support this command; because of common implementation defects, it
cannot be automatically determined whether a server supports it or not.
ssl-no-default-ca
Do not load the default CA locations to verify SSL/TLS server certificates. Only
applicable if SSL/TLS support is built using OpenSSL.
ssl-v2-allow
Accept SSLv2 connections. These are normally not allowed because this protocol
version is insecure.
stealthmua
Inhibits the generation of the `Message-Id:' and `User-Agent:' header fields that
include obvious references to mailx. There are two pitfalls associated with this:
First, the message id of outgoing messages is not known anymore. Second, an expert
may still use the remaining information in the header to track down the originating
mail user agent.
verbose
Setting the option verbose is the same as using the -v flag on the command line.
When mailx runs in verbose mode, details of the actual message delivery and
protocol conversations for IMAP, POP3, and SMTP, as well as of other internal
processes, are displayed on the user's terminal, This is sometimes useful to debug
problems. Mailx prints all data that is sent to remote servers in clear texts,
including passwords, so care should be taken that no unauthorized option can view
the screen if this option is enabled.
writebackedited
If this variable is set, messages modified using the edit or visual commands are
written back to the current folder when it is quit. This is only possible for
writable folders in mbox format. Setting this variable also disables MIME decoding
and decryption for the editing commands.
String Options
The string options include the following:
attrlist
A sequence of characters to print in the `attribute' column of a header summary,
each for one type of messages in the following order: new, unread but old, new but
read, read and old, saved, preserved, mboxed, flagged, answered, draft, killed,
start of a collapsed thread, collapsed, classified as junk. The default is
`NUROSPMFATK+-J', or `NU *HMFATK+-J' if bsdflags or the SYSV3 environment variable
are set.
autobcc
Specifies a list of recipients to which a blind carbon copy of each outgoing
message will be sent automatically.
autocc Specifies a list of recipients to which a carbon copy of each outgoing message will
be sent automatically.
autosort
Causes sorted mode (see the sort command) to be entered automatically with the
value of this option as sorting method when a folder is opened.
cmd The default value for the pipe command.
crt The valued option crt is used as a threshold to determine how long a message must
be before PAGER is used to read it. If crt is set without a value, then the height
of the terminal screen stored in the system is used to compute the threshold (see
stty(1)).
DEAD The name of the file to use for saving aborted messages. This defaults to
`dead.letter' in the user's home directory.
EDITOR Pathname of the text editor to use in the edit command and ~e escape. If not
defined, then a default editor is used.
encoding
The default MIME encoding to use in outgoing text messages and message parts.
Valid values are 8bit or quoted-printable. The default is 8bit. In case the mail
transfer system is not ESMTP compliant, quoted-printable should be used instead.
If there is no need to encode a message, 7bit transfer mode is used, without regard
to the value of this variable. Binary data is always encoded in base64 mode.
escape If defined, the first character of this option gives the character to use in the
place of ~ to denote escapes.
folder The name of the directory to use for storing folders of messages. All folder names
that begin with `+' refer to files below that directory. If the directory name
begins with a `/', mailx considers it to be an absolute pathname; otherwise, the
folder directory is found relative to the user's home directory.
The directory name may also refer to an IMAP account; any names that begin with `+'
then refer to IMAP mailboxes on that account. An IMAP folder is normally given in
the form
imaps://mylogin@imap.myisp.example
In this case, the `+' and `@' prefixes for folder names have the same effect (see
the folder command).
Some IMAP servers do not accept the creation of mailboxes in the hierarchy base;
they require that they are created as subfolders of `INBOX'. With such servers, a
folder name of the form
imaps://mylogin@imap.myisp.example/INBOX.
should be used (the last character is the server's hierarchy delimiter). Folder
names prefixed by `+' will then refer to folders below `INBOX', while folder names
prefixed by `@' refer to folders below the hierarchy base. See the imap namespace
command for a method to detect the appropriate prefix and delimiter.
folder-hook
When a folder is opened and this variable is set, the macro corresponding to the
value of this variable is executed. The macro is also invoked when new mail
arrives, but message lists for commands executed from the macro only include newly
arrived messages then.
folder-hook-fullname
When a folder named fullname is opened, the macro corresponding to the value of
this variable is executed. Unlike other folder specifications, the fully expanded
name of a folder, without metacharacters, is used to avoid ambiguities. The macro
specified with folder-hook is not executed if this variable is effective for a
folder (unless it is explicitly invoked within the called macro).
from The address (or a list of addresses) to put into the `From:' field of the message
header. If replying to a message, these addresses are handled as if they were in
the alternates list. If the machine's hostname is not valid at the Internet (for
example at a dialup machine), either this variable or hostname have to be set to
get correct Message-ID header fields. If from contains more than one address, the
sender variable must also be set.
fwdheading
The string to print before the text of a message with the forward command (unless
the forward-as-attachment variable is set). Defaults to ``-------- Original
Message --------'' if unset. If it is set to the empty string, no heading is
printed.
headline
A format string to use for the header summary, similar to printf formats. A `%'
character introduces a format specifier. It may be followed by a number indicating
the field width. If the field is a number, the width may be negative, which
indicates that it is to be left-aligned. Valid format specifiers are:
%a Message attributes.
%c The score of the message.
%d The date when the message was received.
%e The indenting level in threaded mode.
%f The address of the message sender.
%i The message thread structure.
%l The number of lines of the message.
%m Message number.
%o The number of octets (bytes) in the message.
%s Message subject (if any).
%S Message subject (if any) in double quotes.
%t The position in threaded/sorted order.
%> A `>' for the current message, otherwise ` '.
%< A `<' for the current message, otherwise ` '.
%% A `%' character.
The default is `%>%a%m %18f %16d %4l/%-5o %i%s', or
`%>%a%m %20f %16d %3l/%-5o %i%S' if bsdcompat is set.
hostname
Use this string as hostname when expanding local addresses instead of the value
obtained from uname(2) and getaddrinfo(3).
imap-auth
Sets the IMAP authentication method. Valid values are `login' for the usual
password-based authentication (the default), `cram-md5', which is a password-based
authentication that does not send the password over the network in clear text, and
`gssapi' for GSSAPI-based authentication.
imap-auth-user@host
Sets the IMAP authentication method for a specific account.
imap-cache
Enables caching of IMAP mailboxes. The value of this variable must point to a
directory that is either existent or can be created by mailx. All contents of the
cache can be deleted by mailx at any time; it is not safe to make assumptions about
them.
imap-keepalive
IMAP servers may close the connection after a period of inactivity; the standard
requires this to be at least 30 minutes, but practical experience may vary.
Setting this variable to a numeric value greater than 0 causes a NOOP command to be
sent each value seconds if no other operation is performed.
imap-list-depth
When retrieving the list of folders on an IMAP server, the folders command stops
after it has reached a certain depth to avoid possible infinite loops. The value
of this variable sets the maximum depth allowed. The default is 2. If the folder
separator on the current IMAP server is a slash `/', this variable has no effect,
and the folders command does not descend to subfolders.
indentprefix
String used by the `~m' and `~M' tilde escapes and by the quote option for
indenting messages, in place of the normal tab character (^I). Be sure to quote
the value if it contains spaces or tabs.
junkdb The location of the junk mail database. The string is treated like a folder name,
as described for the folder command.
The files in the junk mail database are normally stored in compress(1) format for
saving space. If processing time is considered more important, uncompress(1) can
be used to store them in plain form. Mailx will then work using the uncompressed
files.
LISTER Pathname of the directory lister to use in the folders command when operating on
local mailboxes. Default is /bin/ls.
MAIL Is used as the user's mailbox, if set. Otherwise, a system-dependent default is
used. Can be a protocol:// string (see the folder command for more information).
MAILX_HEAD
A string to put at the beginning of each new message. The escape sequences `\t'
(tabulator) and `\n' (newline) are understood.
MAILX_TAIL
A string to put at the end of each new message. The escape sequences `\t'
(tabulator) and `\n' (newline) are understood.
maximum-unencoded-line-length
Messages that contain lines longer than the value of this variable are encoded in
quoted-printable even if they contain only ASCII characters. The maximum effective
value is 950. If set to 0, all ASCII text messages are encoded in quoted-
printable. S/MIME signed messages are always encoded in quoted-printable
regardless of the value of this variable.
MBOX The name of the mbox file. It can be the name of a folder. The default is `mbox'
in the user's home directory.
NAIL_EXTRA_RC
The name of an optional startup file to be read after ~/.mailrc. This variable is
ignored if it is imported from the environment; it has an effect only if it is set
in /etc/nail.rc or ~/.mailrc to allow bypassing the configuration with e. g.
`MAILRC=/dev/null'. Use this file for commands that are not understood by other
mailx implementations.
newfolders
If this variable has the value maildir, newly created local folders will be in
maildir format.
nss-config-dir
A directory that contains the files certN.db to retrieve certificates, keyN.db to
retrieve private keys, and secmod.db, where N is a digit. These are usually taken
from Mozilla installations, so an appropriate value might be
`~/.mozilla/firefox/default.clm'. Mailx opens these files read-only and does not
modify them. However, if the files are modified by Mozilla while mailx is running,
it will print a `Bad database' message. It may be necessary to create copies of
these files that are exclusively used by mailx then. Only applicable if S/MIME and
SSL/TLS support is built using Network Security Services (NSS).
ORGANIZATION
The value to put into the `Organization:' field of the message header.
PAGER Pathname of the program to use in the more command or when crt variable is set.
The default paginator pg(1) or, in BSD compatibility mode, more(1) is used if this
option is not defined.
password-user@host
Set the password for user when connecting to host. If no such variable is defined
for a host, the user will be asked for a password on standard input. Specifying
passwords in a startup file is generally a security risk, the file should be
readable by the invoking user only.
pipe-content/subcontent
When a MIME message part of content/subcontent type is displayed or it is replied
to, its text is filtered through the value of this variable interpreted as a shell
command. Special care must be taken when using such commands as mail viruses may
be distributed by this method; if messages of type application/x-sh were filtered
through the shell, for example, a message sender could easily execute arbitrary
code on the system mailx is running on.
pop3-keepalive
POP3 servers may close the connection after a period of inactivity; the standard
requires this to be at least 10 minutes, but practical experience may vary.
Setting this variable to a numeric value greater than 0 causes a NOOP command to be
sent each value seconds if no other operation is performed.
prompt The string printed when a command is accepted. Defaults to `? ', or to `& ' if the
bsdcompat variable is set.
quote If set, mailx starts a replying message with the original message prefixed by the
value of the variable indentprefix. Normally, a heading consisting of
`Fromheaderfield wrote:' is printed before the quotation. If the string noheading
is assigned to the quote variable, this heading is omitted. If the string headers
is assigned, the headers selected by the ignore/retain commands are printed above
the message body, thus quote acts like an automatic ~m command then. If the string
allheaders is assigned, all headers are printed above the message body, and all
MIME parts are included, thus quote acts like an automatic ~M command then.
record If defined, gives the pathname of the folder used to record all outgoing mail. If
not defined, then outgoing mail is not so saved. When saving to this folder fails,
the message is not sent but saved to the `dead.letter' file instead.
replyto
A list of addresses to put into the `Reply-To:' field of the message header. If
replying to a message, such addresses are handled as if they were in the alternates
list.
screen When mailx initially prints the message headers, it determines the number to print
by looking at the speed of the terminal. The faster the terminal, the more it
prints. This option overrides this calculation and specifies how many message
headers are printed. This number is also used for scrolling with the z command.
sendcharsets
A comma-separated list of character set names that can be used in Internet mail.
When a message that contains characters not representable in US-ASCII is prepared
for sending, mailx tries to convert its text to each of the given character sets in
order and uses the first appropriate one. The default is `utf-8'.
Character sets assigned to this variable should be ordered in ascending complexity.
That is, the list should start with e.g. `iso-8859-1' for compatibility with older
mail clients, might contain some other language-specific character sets, and should
end with `utf-8' to handle messages that combine texts in multiple languages.
sender An address that is put into the `Sender:' field of outgoing messages. This field
needs not normally be present. It is, however, required if the `From:' field
contains more than one address. It can also be used to indicate that a message was
sent on behalf of somebody other; in this case, `From:' should contain the address
of the person that took responsibility for the message, and `Sender:' should
contain the address of the person that actually sent the message. The sender
address is handled as if it were in the alternates list.
sendmail
To use an alternate mail delivery system, set this option to the full pathname of
the program to use. This should be used with care.
SHELL Pathname of the shell to use in the ! command and the ~! escape. A default shell
is used if this option is not defined.
Sign A string for use with the ~A command.
sign A string for use with the ~a command.
signature
Must correspond to the name of a readable file if set. The file's content is then
appended to each singlepart message and to the first part of each multipart
message. Be warned that there is no possibility to edit the signature for an
individual message.
smime-ca-dir
Specifies a directory with CA certificates for verification of S/MIME signed
messages. The format is the same as described in SSL_CTX_load_verify_locations(3).
Only applicable if S/MIME support is built using OpenSSL.
smime-ca-file
Specifies a file with CA certificates for verification of S/MIME signed messages.
The format is the same as described in SSL_CTX_load_verify_locations(3). Only
applicable if S/MIME support is built using OpenSSL.
smime-cipher-user@host
Specifies a cipher to use when generating S/MIME encrypted messages for user@host.
Valid ciphers are rc2-40 (RC2 with 40 bits), rc2-64 (RC2 with 64 bits), des (DES,
56 bits) and des-ede3 (3DES, 112/168 bits). The default is 3DES. It is not
recommended to use the other ciphers unless a recipient's client is actually unable
to handle 3DES since they are comparatively weak; but even so, the recipient should
upgrade his software in preference.
smime-crl-file
Specifies a file that contains a CRL in PEM format to use when verifying S/MIME
messages. Only applicable if S/MIME support is built using OpenSSL.
smime-crl-dir
Specifies a directory that contains files with CRLs in PEM format to use when
verifying S/MIME messages. Only applicable if S/MIME support is built using
OpenSSL.
smime-encrypt-user@host
If this variable is set, messages to user@host are encrypted before sending. If
S/MIME support is built using OpenSSL, the value of the variable must be set to the
name of a file that contains a certificate in PEM format. If S/MIME support is
built using NSS, the value of this variable is ignored, but if multiple
certificates for user@host are available, the smime-nickname-user@host variable
should be set. Otherwise a certificate for the recipient is automatically
retrieved from the certificate database, if possible.
If a message is sent to multiple recipients, each of them for whom a corresponding
variable is set will receive an individually encrypted message; other recipients
will continue to receive the message in plain text unless the smime-force-
encryption variable is set. It is recommended to sign encrypted messages, i.e. to
also set the smime-sign variable.
smime-nickname-user@host
Specifies the nickname of a certificate to be used when encrypting messages for
user@host . Only applicable if S/MIME support is built using NSS.
smime-sign-cert
Points to a file in PEM format that contains the user's private key as well as his
certificate. Both are used with S/MIME for signing and decrypting messages. Only
applicable if S/MIME support is built using OpenSSL.
smime-sign-cert-user@host
Overrides smime-sign-cert for the specific addresses. When signing messages and
the value of the from variable is set to user@host, the specific file is used.
When decrypting messages, their recipient fields (To: and Cc:) are searched for
addresses for which such a variable is set. Mailx always uses the first address
that matches, so if the same message is sent to more than one of the user's
addresses using different encryption keys, decryption might fail. Only applicable
if S/MIME support is built using OpenSSL.
smime-sign-nickname
Specifies that the named certificate be used for signing mail. If this variable is
not set, but a single certificate matching the current from address is found in the
database, that one is used automatically. Only applicable if S/MIME support is
built using NSS.
smime-sign-nickname-user@host
Overrides smime-sign-nickname for a specific address. Only applicable if S/MIME
support is built using NSS.
smtp Normally, mailx invokes sendmail(8) directly to transfer messages. If the smtp
variable is set, a SMTP connection to the server specified by the value of this
variable is used instead. If the SMTP server does not use the standard port, a
value of server:port can be given, with port as a name or as a number.
There are two possible methods to get SSL/TLS encrypted SMTP sessions: First, the
STARTTLS command can be used to encrypt a session after it has been initiated, but
before any user-related data has been sent; see smtp-use-starttls above. Second,
some servers accept sessions that are encrypted from their beginning on. This mode
is configured by assigning smtps://server[:port] to the smtp variable.
The SMTP transfer is executed in a child process; unless either the sendwait or the
verbose variable is set, this process runs asynchronously. If it receives a TERM
signal, it will abort and save the message to the `dead.letter' file.
smtp-auth
Sets the SMTP authentication method. If set to `login', or if unset and smtp-auth-
user is set, AUTH LOGIN is used. If set to `cram-md5', AUTH CRAM-MD5 is used; if
set to `plain', AUTH PLAIN is used. Otherwise, no SMTP authentication is
performed.
smtp-auth-user@host
Overrides smtp-auth for specific values of sender addresses, depending on the from
variable.
smtp-auth-password
Sets the global password for SMTP AUTH. Both user and password have to be given
for AUTH LOGIN and AUTH CRAM-MD5.
smtp-auth-password-user@host
Overrides smtp-auth-password for specific values of sender addresses, depending on
the from variable.
smtp-auth-user
Sets the global user name for SMTP AUTH. Both user and password have to be given
for AUTH LOGIN and AUTH CRAM-MD5.
If this variable is set but neither smtp-auth-password or a matching smtp-auth-
password-user@host can be found, mailx will as for a password on the user's
terminal.
smtp-auth-user-user@host
Overrides smtp-auth-user for specific values of sender addresses, depending on the
from variable.
ssl-ca-dir
Specifies a directory with CA certificates for verification of SSL/TLS server
certificates. See SSL_CTX_load_verify_locations(3) for more information. Only
applicable if SSL/TLS support is built using OpenSSL.
ssl-ca-file
Specifies a file with CA certificates for verification of SSL/TLS server
certificates. See SSL_CTX_load_verify_locations(3) for more information. Only
applicable if SSL/TLS support is built using OpenSSL.
ssl-cert
Sets the file name for a SSL/TLS client certificate required by some servers. Only
applicable if SSL/TLS support is built using OpenSSL.
ssl-cert-user@host
Sets an account-specific file name for a SSL/TLS client certificate required by
some servers. Overrides ssl-cert for the specified account. Only applicable if
SSL/TLS support is built using OpenSSL.
ssl-cipher-list
Specifies a list of ciphers for SSL/TLS connections. See ciphers(1) for more
information. Only applicable if SSL/TLS support is built using OpenSSL.
ssl-crl-file
Specifies a file that contains a CRL in PEM format to use when verifying SSL/TLS
server certificates. Only applicable if SSL/TLS support is built using OpenSSL.
ssl-crl-dir
Specifies a directory that contains files with CRLs in PEM format to use when
verifying SSL/TLS server certificates. Only applicable if SSL/TLS support is built
using OpenSSL.
ssl-key
Sets the file name for the private key of a SSL/TLS client certificate. If unset,
the name of the certificate file is used. The file is expected to be in PEM
format. Only applicable if SSL/TLS support is built using OpenSSL.
ssl-key-user@host
Sets an account-specific file name for the private key of a SSL/TLS client
certificate. Overrides ssl-key for the specified account. Only applicable if
SSL/TLS support is built using OpenSSL.
ssl-method
Selects a SSL/TLS protocol version; valid values are `ssl3', and `tls1'. If unset,
the method is selected automatically, if possible.
ssl-method-user@host
Overrides ssl-method for a specific account.
ssl-rand-egd
Gives the pathname to an entropy daemon socket, see RAND_egd(3).
ssl-rand-file
Gives the pathname to a file with entropy data, see RAND_load_file(3). If the file
is a regular file writable by the invoking user, new data is written to it after it
has been loaded. Only applicable if SSL/TLS support is built using OpenSSL.
ssl-verify
Sets the action to be performed if an error occurs during SSL/TLS server
certificate validation. Valid values are `strict' (fail and close connection
immediately), `ask' (ask whether to continue on standard input), `warn' (print a
warning and continue), `ignore' (do not perform validation). The default is `ask'.
ssl-verify-user@host
Overrides ssl-verify for a specific account.
toplines
If defined, gives the number of lines of a message to be printed out with the top
command; normally, the first five lines are printed.
ttycharset
The character set of the terminal mailx operates on. There is normally no need to
set this variable since mailx can determine this automatically by looking at the
LC_CTYPE locale setting; if this succeeds, the value is assigned at startup and
will be displayed by the set command. Note that this is not necessarily a
character set name that can be used in Internet messages.
VISUAL Pathname of the text editor to use in the visual command and ~v escape.
ENVIRONMENT VARIABLES
Besides the variables described above, mailx uses the following environment strings:
HOME The user's home directory.
LANG, LC_ALL, LC_COLLATE, LC_CTYPE, LC_MESSAGES
See locale(7).
MAILRC Is used as startup file instead of ~/.mailrc if set. When mailx scripts are
invoked on behalf of other users, this variable should be set to `/dev/null' to
avoid side-effects from reading their configuration files.
NAILRC If this variable is set and MAILRC is not set, it is read as startup file.
SYSV3 Changes the letters printed in the first column of a header summary.
TMPDIR Used as directory for temporary files instead of /tmp, if set.
FILES
~/.mailrc
File giving initial commands.
/etc/nail.rc
System wide initialization file.
~/.mime.types
Personal MIME types.
/etc/mime.types
System wide MIME types.
EXAMPLES
Getting started
The mailx command has two distinct usages, according to whether one wants to send or
receive mail. Sending mail is simple: to send a message to a user whose email address is,
say, <bill@host.example>, use the shell command:
$ mailx bill@host.example
then type your message. Mailx will prompt you for a message subject first; after that,
lines typed by you form the body of the message. When you reach the end of the message,
type an EOT (control-d) at the beginning of a line, which will cause mailx to echo `EOT'
and return you to the shell.
If, while you are composing the message you decide that you do not wish to send it after
all, you can abort the letter with a RUBOUT. Typing a single RUBOUT causes mailx to print
`(Interrupt -- one more to kill letter)'. Typing a second RUBOUT causes mailx to save
your partial letter on the file `dead.letter' in your home directory and abort the letter.
Once you have sent mail to someone, there is no way to undo the act, so be careful.
If you want to send the same message to several other people, you can list their email
addresses on the command line. Thus,
$ mailx sam@workstation.example bob@server.example
Subject: Fees
Tuition fees are due next Friday. Don't forget!
<Control-d>
EOT
$
will send the reminder to <sam@workstation.example>. and <bob@server.example>.
To read your mail, simply type
$ mailx
Mailx will respond by typing its version number and date and then listing the messages you
have waiting. Then it will type a prompt and await your command. The messages are
assigned numbers starting with 1—you refer to the messages with these numbers. Mailx
keeps track of which messages are new (have been sent since you last read your mail) and
read (have been read by you). New messages have an N next to them in the header listing
and old, but unread messages have a U next to them. Mailx keeps track of new/old and
read/unread messages by putting a header field called Status into your messages.
To look at a specific message, use the type command, which may be abbreviated to simply t
. For example, if you had the following messages:
O 1 drfoo@myhost.example Wed Sep 1 19:52 18/631 "Fees"
O 2 sam@friends.example Thu Sep 2 00:08 30/895
you could examine the first message by giving the command:
type 1
which might cause mailx to respond with, for example:
Message 1:
From drfoo@myhost.example Wed Sep 1 19:52:25 2004
Subject: Fees
Status: R
Tuition fees are due next Wednesday. Don't forget!
Many mailx commands that operate on messages take a message number as an argument like the
type command. For these commands, there is a notion of a current message. When you enter
the mailx program, the current message is initially the first (or the first recent) one.
Thus, you can often omit the message number and use, for example,
t
to type the current message. As a further shorthand, you can type a message by simply
giving its message number. Hence,
1
would type the first message.
Frequently, it is useful to read the messages in your mailbox in order, one after another.
You can read the next message in mailx by simply typing a newline. As a special case, you
can type a newline as your first command to mailx to type the first message.
If, after typing a message, you wish to immediately send a reply, you can do so with the
reply command. This command, like type, takes a message number as an argument. mailx
then begins a message addressed to the user who sent you the message. You may then type
in your letter in reply, followed by a <control-d> at the beginning of a line, as before.
Note that mailx copies the subject header from the original message. This is useful in
that correspondence about a particular matter will tend to retain the same subject
heading, making it easy to recognize. If there are other header fields in the message,
like `Cc:', the information found will also be used.
Sometimes you will receive a message that has been sent to several people and wish to
reply only to the person who sent it. Reply with a capital R replies to a message, but
sends a copy to the sender only.
If you wish, while reading your mail, to send a message to someone, but not as a reply to
one of your messages, you can send the message directly with the mail command, which takes
as arguments the names of the recipients you wish to send to. For example, to send a
message to <frank@machine.example>, you would do:
mail frank@machine.example
To delete a message from the mail folder, you can use the delete command. In addition to
not saving deleted messages, mailx will not let you type them, either. The effect is to
make the message disappear altogether, along with its number.
Many features of mailx can be tailored to your liking with the set command. The set
command has two forms, depending on whether you are setting a binary option or a valued
option. Binary options are either on or off. For example, the askcc option informs mailx
that each time you send a message, you want it to prompt you for a `Cc:' header, to be
included in the message. To set the askcc option, you would type
set askcc
Valued options are values which mailx uses to adapt to your tastes. For example, the
record option tells mailx where to save messages sent by you, and is specified by
set record=Sent
for example. Note that no spaces are allowed in set record=Sent .
Mailx includes a simple facility for maintaining groups of messages together in folders.
To use the folder facility, you must tell mailx where you wish to keep your folders. Each
folder of messages will be a single file. For convenience, all of your folders are kept
in a single directory of your choosing. To tell mailx where your folder directory is, put
a line of the form
set folder=letters
in your .mailrc file. If, as in the example above, your folder directory does not begin
with a `/', mailx will assume that your folder directory is to be found starting from your
home directory.
Anywhere a file name is expected, you can use a folder name, preceded with `+'. For
example, to put a message into a folder with the save command, you can use:
save +classwork
to save the current message in the classwork folder. If the classwork folder does not yet
exist, it will be created. Note that messages which are saved with the save command are
automatically removed from your system mailbox.
In order to make a copy of a message in a folder without causing that message to be
removed from your system mailbox, use the copy command, which is identical in all other
respects to the save command.
The folder command can be used to direct mailx to the contents of a different folder. For
example,
folder +classwork
directs mailx to read the contents of the classwork folder. All of the commands that you
can use on your system mailbox are also applicable to folders, including type, delete, and
reply. To inquire which folder you are currently editing, use simply:
folder
To list your current set of folders, use the folders command.
Finally, the help command is available to print out a brief summary of the most important
mailx commands.
While typing in a message to be sent to others, it is often useful to be able to invoke
the text editor on the partial message, print the message, execute a shell command, or do
some other auxiliary function. Mailx provides these capabilities through tilde escapes ,
which consist of a tilde (~) at the beginning of a line, followed by a single character
which indicates the function to be performed. For example, to print the text of the
message so far, use:
~p
which will print a line of dashes, the recipients of your message, and the text of the
message so far. A list of the most important tilde escapes is available with `~?'.
IMAP or POP3 client setup
First you need the following data from your ISP: the host name of the IMAP or POP3 server,
user name and password for this server, and a notice whether the server uses SSL/TLS
encryption. Assuming the host name is `server.myisp.example' and your user name for that
server is `mylogin', you can refer to this account using the folder command or -f command
line option with
imaps://mylogin@server.myisp.example
(This string is not necessarily the same as your Internet mail address.) You can replace
`imaps://' with `imap://' if the server does not support SSL/TLS. (If SSL/TLS support is
built using NSS, the nss-config-dir variable must be set before a connection can be
initiated, see above). Use `pop3s://' or `pop3://' if the server does not offer IMAP.
You should use IMAP if you can, though; first because it requires fewer network operations
than POP3 to get the contents of the mailbox and is thus faster; and second because
message attributes are maintained by the IMAP server, so you can easily distinguish new
and old messages each time you connect. Even if the server does not accept IMAPS or POP3S
connections, it is possible that it supports the STARTTLS method to make a session SSL/TLS
encrypted after the initial connection has been performed, but before authentication
begins. The only reliable method to see if this works is to try it; enter one of
set imap-use-starttls
set pop3-use-starttls
before you initiate the connection.
As you probably want messages to be deleted from this account after saving them, prefix it
with `%:'. The shortcut command can be used to avoid typing that many characters every
time you want to connect:
shortcut myisp %:imaps://mylogin@server.myisp.example
You might want to put this string into a startup file. As the shortcut command is
specific to this implementation of mailx and will confuse other implementations, it should
not be used in ~/.mailrc, instead, put
set NAIL_EXTRA_RC=~/.nailrc
in ~/.mailrc and create a file ~/.nailrc containing the shortcut command above. You can
then access your remote mailbox by invoking `mailx -f myisp' on the command line, or by
executing `fi myisp' within mailx.
If you want to use more than one IMAP mailbox on a server, or if you want to use the IMAP
server for mail storage too, the account command (which is also mailx-specific) is more
appropriate than the shortcut command. You can put the following in ~/.nailrc:
account myisp {
set folder=imaps://mylogin@server.myisp.example
set record=+Sent MBOX=+mbox outfolder
}
and can then access incoming mail for this account by invoking `mailx -A myisp' on the
command line, or by executing `ac myisp' within mailx. After that, a command like `copy 1
+otherfolder' will refer to otherfolder on the IMAP server. In particular, `fi &' will
change to the mbox folder, and `fi +Sent' will show your recorded sent mail, with both
folders located on the IMAP server.
Mailx will ask you for a password string each time you connect to a remote account. If
you can reasonably trust the security of your workstation, you can give this password in
the startup file as
set password-mylogin@server.myisp.example="SECRET"
You should change the permissions of this file to 0600, see chmod(1).
Mailx supports different authentication methods for both IMAP and POP3. If Kerberos is
used at your location, you can try to activate GSSAPI-based authentication by
set imap-auth=gssapi
The advantage of this method is that mailx does not need to know your password at all, nor
needs to send sensitive data over the network. Otherwise, the options
set imap-auth=cram-md5
set pop3-use-apop
for IMAP and POP3, respectively, offer authentication methods that avoid to send the
password in clear text over the network, which is especially important if SSL/TLS cannot
be used. If the server does not offer any of these authentication methods, conventional
user/password based authentication must be used. It is sometimes helpful to set the
verbose option when authentication problems occur. Mailx will display all data sent to
the server in clear text on the screen with this option, including passwords. You should
thus take care that no unauthorized person can look at your terminal when this option is
set.
If you regularly use the same workstation to access IMAP accounts, you can greatly enhance
performance by enabling local caching of IMAP messages. For any message that has been
fully or partially fetched from the server, a local copy is made and is used when the
message is accessed again, so most data is transferred over the network once only. To
enable the IMAP cache, select a local directory name and put
set imap-cache=~/localdirectory
in the startup file. All files within that directory can be overwritten or deleted by
mailx at any time, so you should not use the directory to store other information.
Once the cache contains some messages, it is not strictly necessary anymore to open a
connection to the IMAP server to access them. When mailx is invoked with the -D option,
or when the disconnected variable is set, only cached data is used for any folder you
open. Messages that have not yet been completely cached are not available then, but all
other messages can be handled as usual. Changes made to IMAP mailboxes in disconnected
mode are committed to the IMAP server next time it is used in online mode. Synchronizing
the local status with the status on the server is thus partially within your
responsibility; if you forget to initiate a connection to the server again before you
leave your location, changes made on one workstation are not available on others. Also if
you alter IMAP mailboxes from a workstation while uncommitted changes are still pending on
another, the latter data may become invalid. The same might also happen because of
internal server status changes. You should thus carefully evaluate this feature in your
environment before you rely on it.
Many servers will close the connection after a short period of inactivity. Use one of
set pop3-keepalive=30
set imap-keepalive=240
to send a keepalive message each 30 seconds for POP3, or each 4 minutes for IMAP.
If you encounter problems connecting to a SSL/TLS server, try the ssl-rand-egd and ssl-
rand-file variables (see the OpenSSL FAQ for more information) or specify the protocol
version with ssl-method. Contact your ISP if you need a client certificate or if
verification of the server certificate fails. If the failed certificate is indeed valid,
fetch its CA certificate by executing the shell command
$ openssl s_client </dev/null -showcerts -connect \
server.myisp.example:imaps 2>&1 | tee log
(see s_client(1)) and put it into the file specified with ssl-ca-file. The data you need
is located at the end of the certificate chain within (and including) the `BEGIN
CERTIFICATE' and `END CERTIFICATE' lines. (Note that it is possible to fetch a forged
certificate by this method. You can only completely rely on the authenticity of the CA
certificate if you fetch it in a way that is trusted by other means, such as by personally
receiving the certificate on storage media.)
Creating a score file or message filter
The scoring commands are best separated from other configuration for clarity, and are
mostly mailx specific. It is thus recommended to put them in a separate file that is
sourced from your NAIL_EXTRA_RC as follows:
source ~/.scores
The .scores file could then look as follows:
define list {
score (subject "important discussion") +10
score (subject "annoying discussion") -10
score (from "nicefellow@goodnet") +15
score (from "badguy@poornet") -5
move (header x-spam-flag "+++++") +junk
}
set folder-hook-imap://user@host/public.list=list
In this scheme, you would see any mail from `nicefellow@goodnet', even if the surrounding
discussion is annoying; but you normally would not see mail from `badguy@poornet', unless
he participates in the important discussion. Messages that are marked with five or more
plus characters in their `X-Spam-Flag' field (inserted by some server-side filtering
software) are moved to the folder `junk' in the folder directory.
Be aware that all criteria in () lead to substring matches, so you would also score
messages from e.g. `notsobadguy@poornetmakers' negative here. It is possible to select
addresses exactly using "address" message specifications, but these cannot be executed
remotely and will thus cause all headers to be downloaded from IMAP servers while looking
for matches.
When searching messages on an IMAP server, best performance is usually achieved by sending
as many criteria as possible in one large () specification, because each single such
specification will result in a separate network operation.
Activating the Bayesian filter
The Bayesian junk mail filter works by examining the words contained in messages. You
decide yourself what a good and what a bad message is. Thus the resulting filter is your
very personal one; once it is correctly set up, it will filter only messages similar to
those previously specified by you.
To use the Bayesian filter, a location for the junk mail database must be defined first:
set junkdb=~/.junkdb
The junk mail database does not contain actual words extracted from messages, but hashed
representations of them. A foreign person who can read the database could only examine
the frequency of previously known words in your mail.
If you have sufficient disk space (several 10 MB) available, it is recommended that you
set the chained-junk-tokens option. The filter will then also consider two-word tokens,
improving its accuracy.
A set of good messages and junk messages must now be available; it is also possible to use
the incoming new messages for this purpose, although it will of course take some time
until the filter becomes useful then. Do not underestimate the amount of statistical data
needed; some hundred messages are typically necessary to get satisfactory results, and
many thousand messages for best operation. You have to pass the good messages to the good
command, and the junk messages to the junk command. If you ever accidentally mark a good
message as junk or vice-versa, call the ungood or unjunk command to correct this.
Once a reasonable amount of statistics has been collected, new messages can be classified
automatically. The classify command marks all messages that the filter considers to be
junk, but it does not perform any action on them by default. It is recommended that you
move these messages into a separate folder just for the case that false positives occur,
or to pass them to the junk command later again to further improve the junk mail database.
To automatically move incoming junk messages every time the inbox is opened, put lines
like the following into your .scores file (or whatever name you gave to the file in the
last example):
define junkfilter {
classify (smaller 20000) :n
move :j +junk
}
set folder-hook-imap://user@host/INBOX=junkfilter
If you set the verbose option before running the classify command, mailx prints the words
it uses for calculating the junk status along with their statistical probabilities. This
can help you to find out why some messages are not classified as you would like them to
be. To see the statistical probability of a given word, use the probability command.
If a junk message was not recognized as such, use the junk command to correct this. Also
if you encounter a false positive (a good message that was wrongly classified as junk),
pass it to the good command.
Since the classify command must examine the entire text of all new messages in the
respective folder, this will also cause all of them to be downloaded from the IMAP server.
You should thus restrict the size of messages for automatic filtering. If server-based
filtering is also available, you might try if that works for you first.
Reading HTML mail
You need either the w3m or lynx utility or another command-line web browser that can write
plain text to standard output.
set pipe-text/html="w3m -dump -T text/html"
or
set pipe-text/html="lynx -dump -force_html /dev/stdin"
will then cause HTML message parts to be converted into a more friendly form.
Viewing PDF attachments
Most PDF viewers do not accept input directly from a pipe. It is thus necessary to store
the attachment in a temporary file, as with
set pipe-application/pdf="cat >/tmp/mailx$$.pdf; \
acroread /tmp/mailx$$.pdf; rm /tmp/mailx$$.pdf"
Note that security defects are discovered in PDF viewers from time to time. Automatical
command execution like this can compromise your system security, in particular if you stay
not always informed about such issues.
Signed and encrypted messages with S/MIME
S/MIME provides two central mechanisms: message signing and message encryption. A signed
message contains some data in addition to the regular text. The data can be used to
verify that the message was sent using a valid certificate, that the sender's address in
the message header matches that in the certificate, and that the message text has not been
altered. Signing a message does not change its regular text; it can be read regardless of
whether the recipient's software is able to handle S/MIME. It is thus usually possible to
sign all outgoing messages if so desired.—Encryption, in contrast, makes the message text
invisible for all people except those who have access to the secret decryption key. To
encrypt a message, the specific recipient's public encryption key must be known. It is
thus not possible to send encrypted mail to people unless their key has been retrieved
from either previous communication or public key directories. A message should always be
signed before it is encrypted. Otherwise, it is still possible that the encrypted message
text is altered.
A central concept to S/MIME is that of the certification authority (CA). A CA is a
trusted institution that issues certificates. For each of these certificates, it can be
verified that it really originates from the CA, provided that the CA's own certificate is
previously known. A set of CA certificates is usually delivered with OpenSSL and
installed on your system. If you trust the source of your OpenSSL software installation,
this offers reasonable security for S/MIME on the Internet. In general, a certificate
cannot be more secure than the method its CA certificate has been retrieved with, though.
Thus if you download a CA certificate from the Internet, you can only trust the messages
you verify using that certificate as much as you trust the download process.
The first thing you need for participating in S/MIME message exchange is your personal
certificate, including a private key. The certificate contains public information, in
particular your name and your email address, and the public key that is used by others to
encrypt messages for you, and to verify signed messages they supposedly received from you.
The certificate is included in each signed message you send. The private key must be kept
secret. It is used to decrypt messages that were previously encrypted with your public
key, and to sign messages.
For personal use, it is recommended that you get a S/MIME certificate from one of the
major CAs on the Internet using your WWW browser. (Many CAs offer such certificates for
free.) You will usually receive a combined certificate and private key in PKCS#12 format
which mailx does not directly accept if S/MIME support is built using OpenSSL. To convert
it to PEM format, use the following shell command:
$ openssl pkcs12 -in cert.p12 -out cert.pem -clcerts \
-nodes
If you omit the -nodes parameter, you can specifiy an additional PEM pass phrase for
protecting the private key. Mailx will then ask you for that pass phrase each time it
signs or decrypts a message. You can then use
set smime-sign-cert-myname@myisp.example=cert.pem
to make this private key and certificate known to mailx.
If S/MIME support is built using NSS, the PKCS#12 file must be installed using Mozilla
(provided that nss-config-dir is set appropriately, see above), and no further action is
necessary unless multiple user certificates for the same email address are installed. In
this case, the smime-sign-nickname variable has to be set appropriately.
You can now sign outgoing messages. Just use
set smime-sign
to do so.
From each signed message you send, the recipient can fetch your certificate and use it to
send encrypted mail back to you. Accordingly if somebody sends you a signed message, you
can do the same. First use the verify command to check the validity of the certificate.
After that, retrieve the certificate and tell mailx that it should use it for encryption:
certsave filename
set smime-encrypt-user@host=filename
If S/MIME support is built using NSS, the saved certificate must be installed using
Mozilla. The value of the smime-encrypt-user@host is ignored then, but if multiple
certificates for the recipient are available, the smime-nickname-user@host variable must
be set.
You should carefully consider if you prefer to store encrypted messages in decrypted form.
If you do, anybody who has access to your mail folders can read them, but if you do not,
you might be unable to read them yourself later if you happen to lose your private key.
The decrypt command saves messages in decrypted form, while the save, copy, and move
commands leave them encrypted.
Note that neither S/MIME signing nor encryption applies to message subjects or other
header fields. Thus they may not contain sensitive information for encrypted messages,
and cannot be trusted even if the message content has been verified. When sending signed
messages, it is recommended to repeat any important header information in the message
text.
Using CRLs with S/MIME or SSL/TLS
Certification authorities (CAs) issue certificate revocation lists (CRLs) on a regular
basis. These lists contain the serial numbers of certificates that have been declared
invalid after they have been issued. Such usually happens because the private key for the
certificate has been compromised, because the owner of the certificate has left the
organization that is mentioned in the certificate, etc. To seriously use S/MIME or
SSL/TLS verification, an up-to-date CRL is required for each trusted CA. There is
otherwise no method to distinguish between valid and invalidated certificates. Mailx
currently offers no mechanism to fetch CRLs, or to access them on the Internet, so you
have to retrieve them by some external mechanism.
If S/MIME and SSL/TLS support are built using OpenSSL, mailx accepts CRLs in PEM format
only; CRLs in DER format must be converted, e.g. with the shell command
$ openssl crl -inform DER -in crl.der -out crl.pem
To tell mailx about the CRLs, a directory that contains all CRL files (and no other files)
must be created. The smime-crl-dir or ssl-crl-dir variables, respectively, must then be
set to point to that directory. After that, mailx requires a CRL to be present for each
CA that is used to verify a certificate.
If S/MIME and SSL/TLS support are built using NSS, CRLs can be imported in Mozilla
applications (provided that nss-config-dir is set appropriately).
Sending mail from scripts
If you want to send mail from scripts, you must be aware that mailx reads the user's
configuration files by default. So unless your script is only intended for your own
personal use (as e.g. a cron job), you need to circumvent this by invoking mailx like
MAILRC=/dev/null mailx -n
You then need to create a configuration for mailx for your script. This can be done by
either pointing the MAILRC variable to a custom configuration file, or by passing the
configuration in environment variables. Since many of the configuration options are not
valid shell variables, the env command is useful in this situation. An invocation could
thus look like
env MAILRC=/dev/null from=scriptreply@domain smtp=host \
smtp-auth-user=login smtp-auth-password=secret \
smtp-auth=login mailx -n -s "subject" \
-a attachment_file recipient@domain <content_file
SEE ALSO
fmt(1), newaliases(1), openssl(1), pg(1), more(1), vacation(1), ssl(3), aliases(5),
locale(7), mailaddr(7), sendmail(8)
NOTES
Variables in the environment passed to mailx cannot be unset.
The character set conversion relies on the iconv(3) function. Its functionality differs
widely between the various system environments mailx runs on. If the message `Cannot
convert from a to b' appears, either some characters within the message header or text are
not appropriate for the currently selected terminal character set, or the needed
conversion is not supported by the system. In the first case, it is necessary to set an
appropriate LC_CTYPE locale (e.g. en_US) or the ttycharset variable. In the second case,
the sendcharsets and ttycharset variables must be set to the same value to inhibit
character set conversion. If iconv() is not available at all, the value assigned to
sendcharsets must match the character set that is used on the terminal.
Mailx expects input text to be in Unix format, with lines separated by newline (^J, \n)
characters only. Non-Unix text files that use carriage return (^M, \r) characters in
addition will be treated as binary data; to send such files as text, strip these
characters e. g. by
tr -d '\015' <input | mailx . . .
or fix the tools that generate them.
Limitations with IMAP mailboxes are: It is not possible to edit messages, but it is
possible to append them. Thus to edit a message, create a local copy of it, edit it,
append it, and delete the original. The line count for the header display is only
appropriate if the entire message has been downloaded from the server. The marking of
messages as `new' is performed by the IMAP server; use of the exit command instead of quit
will not cause it to be reset, and if the autoinc/newmail variables are unset, messages
that arrived during a session will not be in state `new' anymore when the folder is opened
again. Also if commands queued in disconnected mode are committed, the IMAP server will
delete the `new' flag for all messages in the changed folder, and new messages will appear
as unread when it is selected for viewing later. The `flagged', `answered', and `draft'
attributes are usually permanent, but some IMAP servers are known to drop them without
notification. Message numbers may change with IMAP every time before the prompt is
printed if mailx is notified by the server that messages have been deleted by some other
client or process. In this case, `Expunged n messages' is printed, and message numbers
may have changed.
Limitations with POP3 mailboxes are: It is not possible to edit messages, they can only be
copied and deleted. The line count for the header display is only appropriate if the
entire message has been downloaded from the server. The status field of a message is
maintained by the server between connections; some servers do not update it at all, and
with a server that does, the `exit' command will not cause the message status to be reset.
The `newmail' command and the `newmail' variable have no effect. It is not possible to
rename or to remove POP3 mailboxes.
If a RUBOUT (interrupt) is typed while an IMAP or POP3 operation is in progress, mailx
will wait until the operation can be safely aborted, and will then return to the command
loop and print the prompt again. When a second RUBOUT is typed while mailx is waiting for
the operation to complete, the operation itself will be canceled. In this case, data that
has not been fetched yet will have to be fetched before the next command can be performed.
If the canceled operation was using an SSL/TLS encrypted channel, an error in the SSL
transport will very likely result, and the connection is no longer usable.
As mailx is a mail user agent, it provides only basic SMTP services. If it fails to
contact its upstream SMTP server, it will not make further attempts to transfer the
message at a later time, and it does not leave other information about this condition than
an error message on the terminal and a `dead.letter' file. This is usually not a problem
if the SMTP server is located in the same local network as the computer on which mailx is
run. However, care should be taken when using a remote server of an ISP; it might be
better to set up a local SMTP server then which just acts as a proxy.
Mailx immediately contacts the SMTP server (or /usr/lib/sendmail) even when operating in
disconnected mode. It would not make much sense for mailx to defer outgoing mail since
SMTP servers usually provide much more elaborated delay handling than mailx could perform
as a client. Thus the recommended setup for sending mail in disconnected mode is to
configure a local SMTP server such that it sends outgoing mail as soon as an external
network connection is available again, i.e. to advise it to do that from a network startup
script.
The junk mail filter follows the concepts developed by Paul Graham in his articles, ``A
Plan for Spam'', August 2002, <http://www.paulgraham.com/spam.html>, and ``Better Bayesian
Filtering'', January 2003, <http://www.paulgraham.com/better.html>. Chained tokens are
due to a paper by Jonathan A. Zdziarski, ``Advanced Language Classification using Chained
Tokens'', February 2004, <http://www.nuclearelephant.com/papers/chained.html>.
A mail command appeared in Version 1 AT&T Unix. Berkeley Mail was written in 1978 by Kurt
Shoens. This man page is derived from from The Mail Reference Manual originally written
by Kurt Shoens. Heirloom Mailx enhancements are maintained and documented by Gunnar
Ritter.
Portions of this text are reprinted and reproduced in electronic form from IEEE Std
1003.1, 2003 Edition, Standard for Information Technology — Operating System Interface
(POSIX), The Open Group Base Specifications Issue 6, Copyright © 2001-2003 by the
Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of
any discrepancy between this version and the original IEEE and The Open Group Standard,
the original IEEE and The Open Group Standard is the referee document. The original
Standard can be obtained online at http://www.opengroup.org/unix/online.html .
Redistribution of this material is permitted so long as this notice remains intact.