Sending mail

To send a message to one or more people, mail can be invoked with arguments which are the names of people to whom the mail will be sent. You are then expected to type in your message, followed by a ‘control-D’ at the beginning of a line.

Any flags following the list of recipients, will be passed, together with their arguments, directly to sendmail(1). For example to change your From address to somebody@somewhere.net you can specify:

mail recipient -f somebody@somewhere.net

To prevent multiple copies of a message being sent to the same address, duplicate addresses (after alias expansion) are removed from the bcc-addr, cc-addr, and to-addr lists. In addition, addresses on the cc-addr and to-addr lists are removed if they occur on the bcc-addr list and addresses on the cc-addr list are removed if they occur on the to-addr list. If the to-addr list is empty after these deletions, most systems will insert the line “To: undisclosed recipients:;”.

The section below Replying to or originating mail, describes some features of mail available to help you compose your letter.

Reading mail

In normal usage mail is given no arguments and checks your 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). You can move among the messages much as you move between lines in ed(1), with the commands + and - moving backwards and forwards, and simple numbers.

Disposing of mail

After examining a message you can delete (d) the message or reply (r) to it. Deletion causes the mail program to forget about the message. This is not irreversible; the message can be undeleted (u) by giving its number, or the mail session can be aborted by giving the exit (x) command. Deleted messages will, however, usually disappear never to be seen again.

Specifying messages

Many commands (e.g., delete, from, and print) accept a list of messages as an argument. Messages may be specified by their message number, by a range of messages, or by a pattern string matching certain fields in the header as described below. These message “specs” may be combined by the usual binary boolean operations ‘&’, ‘|’, and ‘^’, which denote, respectively, a logical “and”, “or”, and “xor”. Logical expressions may be grouped with parentheses ‘(’ and ‘)’ and negated with ‘!’. If the binary operator is missing between two message specs, it is assumed to be a ‘|’. This is for simplicity, backwards compatibility, and also to to facilitate using the ‘|’ symbol to denote a pipe. (See enable-pipes.)

Besides the obvious (base10) message numbers, the characters ‘^’, ‘-’, ‘.’, ‘+’, and ‘$’ denote, respectively, the first message, the message before the “dot” (the current message), the “dot” message, the message following the “dot”, and the last message.

A “message range” consists of two message numbers separated by a ‘-’. A ‘*’ denotes all messages and is equivalent to ‘^-$’.

A pattern is a string (not beginning with any of the above special characters). If it does not begin with a ‘/’, it is compared with the senders address. If it begins with a ‘/’, and searchheaders is not defined, the remainder of the string is compared with the subject field. (See searchheaders for searching other header fields or the message body.) If regex-search is not defined, then the comparison is a simple case insensitive substring match. (See regex-search for regular expression matches.)

A list of messages may be restricted by a “colon-modifier” string, i.e., a ‘:’ followed by one or more of the characters:

d	deleted 
e	edited 
m	mboxed 
n	new 
o	old 
p	preserved 
r	read 
s	saved 
t	tagged 
u	unread and not new 
!	invert the meaning of the colon-modifiers

If there are no address specifications other than colon-modifiers, the colon-modifiers apply to all messages. Thus “from netbsd :n” would display the headers of all new messages with ‘netbsd’ in the sender's address, while “from :!r” and “from :nu” would both display all new and unread messages. Multiple colon-modifiers may be specified and a single ‘:’ with no letters following indicates the colon-modifier from the preceding command.

For example:

from 1 12 3-5

would display the headers from messages 1, 3, 4, 5, and 12.

from anon & ( /foo | /bar )

would display all headers that had ‘anon’ in the sender's address and either ‘foo’ or ‘bar’ in the subject line.

Generally, commands cannot select messages that are not displayed, such as deleted or hidden messages, the exception being the undelete command.

Replying to or originating mail

You can use the reply command to set up a response to a message, sending it back to the person who it was from. Text you then type in, up to an end-of-file, defines the contents of the message. While you are composing a message, mail 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 tab stop (see indentprefix variable, below). Other escapes will set up subject fields, add and delete recipients to the message, and allow you 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

You can end a mail session with the quit (q) command. Messages which have been examined go to your 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 system wide distribution lists

It is also possible to create a personal distribution lists so that, for instance, you 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 your home directory. The current list of such aliases can be displayed with the alias command in mail. System wide distribution lists can be created by editing /etc/mail/aliases, see aliases(5) and sendmail(1); these are kept in a different syntax. In mail you send, 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(1).

Network mail (ARPA, UUCP, Berknet)

See mailaddr(7) for a description of network addresses.

mail 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.)

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.

~@ [filelist]

Add the files in the white-space delimited filelist to the attachment list. If filelist is omitted, edit the attachment list, possibly appending to it: For each file in the list the user is prompted to change its attachment data. Changing the filename to empty will delete it from the list. Upon reaching the end of the attachment list, the user is prompted for additional files to attach until an empty filename is given. Filenames containing white-space can only be added in this “edit” mode.

~a

Inserts the autograph string from the sign= option into the message.

~A

Inserts the autograph string from the Sign= option into the message.

~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 your home directory into the message.

~e

Invoke the text editor on the message collected so far. After the editing session is finished, you 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.

~

Identical to ~f, except all message headers are included.

~h

Edit the message header fields, and the options passed to sendmail (the Smopts), 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. If editline(3) support is included, then that line editor is used.

~istring

Inserts the value of the named option into the text of the message.

~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.

~Mmessages

Identical to ~m, except all message headers are included.

~p

Print out the message collected so far, prefaced by the message header fields.

~q

Abort the message being sent, copying the message to “dead.letter” in your home directory if save is set.

~x

Exits as with ~q, except the message is not saved in “dead.letter”.

~rfilename

~<filename

Reads the named file into the message. If the argument begins with ‘!’, the rest of the string is taken as an arbitrary system command and is executed, with the standard output inserted 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 alternative editor (defined by the VISUAL option) on the message collected so far. Usually, the alternative editor will be a screen editor. After you quit the editor, you may resume appending text to the end of your message.

~wfilename

Write the message onto the named file.

~|command

Pipe the message body 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.

~:mail-command

Execute the given mail command. Not all commands, however, are allowed.

~~string

Insert the string of text in the message prefaced by a single ~. If you have changed the escape character, then you should double that character in order to send it.

Mail Options

Options are controlled via set and unset commands. 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. The binary options include the following:

append

Causes messages saved in mbox to be appended to the end rather than prepended. This should always be set (perhaps in /etc/mail.rc).

ask, asksub

Causes mail to prompt you for the subject of each message you send. If you respond with simply a newline, no subject field will be sent.

askcc

Causes you to be prompted for additional carbon copy recipients at the end of each message. Responding with a newline indicates your satisfaction with the current list.

autoinc

Causes new mail to be automatically incorporated when it arrives. Setting this is similar to issuing the inc command at each prompt, except that the current message is not reset when new mail arrives.

askbcc

Causes you to be prompted for additional blind carbon copy recipients at the end of each message. Responding with a newline indicates your satisfaction with the current list.

autoprint

Causes the delete command to behave like dp - thus, after deleting a message, the next one will be typed automatically.

crt

If crt is set, then the PAGER will be used for the print, Print, type, and Type commands. Normally these commands do not invoke the pager. (See page-also.)

debug

Setting the binary option debug is the same as specifying -d on the command line and causes mail to output all sorts of information useful for debugging mail.

dot

The binary option dot causes mail to interpret a period alone on a line as the terminator of a message you are sending.

enable-pipes

If defined, the output of most commands can be piped into a shell command or redirected to a file. The pipe/redirection is signaled by the first occurrence of a ‘|’ or ‘>’ character that is not in a quoted string or in a parenthetical group. This character terminates the mail command line and the remaining string is passed to the shell. For example, assuming normal headers, something like

  from john@ | fgrep -i ' "Re:' | wc

could be used to count how may replies were made by senders with ‘john@’ in their address and

  from john@ >> /tmp/john

would append all the headers from such senders to /tmp/john.

Note: With piping enabled, you cannot use the ‘|’ as a logical “or” operator outside of a parenthetical group. This should not be a problem as it is the default logical operator. (See the Specifying messages section.)

hold

This option is used to hold messages in the system mailbox by default.

ignore

Causes interrupt signals from your terminal to be ignored and echoed as @'s.

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.

mime-attach-list

If set, the command line flag -a will accept a whitespace delimited list of files. Otherwise, its argument is interpreted as a single filename. Warning: If enabled, care must be taken to properly quote files that contain whitespace, both from the shell and from this second expansion done by mail.

mime-decode-header

If set, decode the headers along with the body when mime-decode-message is set. The header decode follows the same rules as the body (see mime-decode-message).

mime-decode-insert

When inserting a message into the mail buffer (~f or ~F), the text inserted will be decoded according to the settings of the mime-decode-message and mime-decode-header variables.

mime-decode-message

If set, the More, more, Page, page, Print, print, Type, and type commands will display decoded the MIME messages. Otherwise, they display the undecoded message. Recall that the View and view commands always have the opposite MIME decoding behavior from these commands.

mime-decode-quote

When quoting a message into the mail buffer (~m or ~M), the text inserted will be decoded according to the settings of the mime-decode-message and mime-decode-header variables.

mime-detach-batch

If set, the detach command does not prompt for anything (unless mime-detach-overwrite is set to ‘ask’), overwriting target files depending on the setting of mime-detach-overwrite.

noheader

Setting the option noheader is the same as giving the -N flag on the command line.

nosave

Normally, when you abort a message with two RUBOUT (erase or delete) mail copies the partial letter to the file “dead.letter” in your home directory. Setting the binary option nosave prevents this.

page-also

A comma or whitespace delimited list of additional commands to page. The comparisons are case insensitive, so if view is in the list, both view and View will page.

pager-off

If set, disable the pager on all commands.

quiet

Suppresses the printing of the version when first invoked.

recursive-commands

When defined, and threading is in effect, the following commands operate on the entire thread (if it is “hidden”) rather than just the top displayed message of the thread:

More Page Print Type View more page print type view 
top 
Save copy save write 
Detach detach 
delete dp dt 
undelete 
hold preserve 
mbox mkread touch unread 
tag untag invtags

If not defined, or if the threads are “exposed”, commands behave exactly as they do in non-threaded mode, i.e., each operates on individual messages.

Replyall

Reverses the sense of reply and Reply commands.

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. If “x” is omitted, it will default to the ‘Subject’ header field. If “y” is omitted, only those messages that contain the field “x” will be matched. The three forms “/from:y”, “/to:y”, and “/body:y” are special. The first will match all messages which contain the substring “y” in the headline (which is added locally at receipt time and begins with “From ”). The second will match all messages containing the substring “y” in the ‘To’, ‘Cc’, or ‘Bcc’ header fields. The third will match all messages which contain the substring “y” in a line of the message body. The check for “from”, “to”, and “body” is case sensitive, so that “/From:y” and “/To:y” can be used to search the ‘From’ and ‘To’ fields, respectively. (See also regex-search.)

smopts-verify

Verify the sendmail options used on outgoing mail if they were obtained from a smopts match. This has no effect if there are no sendmail flags or if the flags were set by the ~h escape.

verbose

Setting the option verbose is the same as using the -v flag on the command line. When mail runs in verbose mode, the actual delivery of messages is displayed on the user's terminal.

Option String Values

EDITOR

Pathname of the text editor to use in the edit command and ~e escape. If not defined, then a default editor is used.

LISTER

Pathname of the directory lister to use in the folders command. Default is /bin/ls.

PAGER

Pathname of the program to use in the more command or when crt variable is set. The default paginator more(1) is used if this option is not defined.

SHELL

Pathname of the shell to use in the ! command and the ~! escape. A default shell is used if this option is not defined.

VISUAL

Pathname of the text editor to use in the visual command and ~v escape.

el-completion-keys

A comma or space delimited list of keys to do editline(3) completion. For example set el-completion-keys=^I,^D will bind completion to both the tab and CTRL-D keys. (Requires editline(3) support.)

el-editor

The line editing mode: must be ‘emacs’ or ‘vi’. If unset, editing is not enabled. (Requires editline(3) support.)

el-history-size

The number of lines of history to remember. If unset, history is not enable. (Requires editline(3) support.)

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. If this name begins with a ‘/’, mail considers it to be an absolute pathname; otherwise, the folder directory is found relative to your home directory.

header-format

If set, use this format string when displaying headers in command mode. The format string supports the following conversions in addition to those of strftime(3):

%?key?

The header field with name ‘key’. Note: if key[0] is ‘-’, ignore the ‘-’ and extract the address portion of the field (i.e., “skin” the field).

%?*string?

If the depth is n, substitute ‘string’ n times. This is intended to be used when displaying an “exposed thread”.

%?&string?

Like %?*string?, but uses the depth relative to the current depth rather than the absolute depth.

%J

The number of header lines in the message.

%K

The number of body lines in the message.

%L

The total number of lines in the message.

%N

The sender's full name (as in the ‘From’ or ‘Sender’ fields).

%O

The message size.

%P

The current “dot” (‘>’) message.

%Q

The message status flag.

%Z

The time zone name (if it exists).

%f

The email address of sender.

%i

The message number.

%n

The sender's login name (taken from the address).

%q

The subject.

%t

The total number of messages.

%z

The GMT offset (if found).

If the format string begins with ‘%??’ then the date will be extracted from the headline. Otherwise it will be extracted from the ‘Date’ header falling back to the headline if that extraction fails. For example, the default format is:

set header-format="%??%P%Q%?* ?%3i %-21.20f %a %b %e %R %3K/%-5O \"%q\""

Note 1: The message status flag ‘%Q’ will display the single character ‘+’ for the parent of a subthread. This will be overwritten by a ‘T’, ‘E’, ‘*’, ‘P’, ‘U’, ‘N’, ‘M’ indicating, respectively, a tagged, modified, saved, preserved, unread, new, or modified message, in that order with the last matching condition being the one displayed. In the case of hidden threads, the entire subthread is searched and the letters above will be displayed in lower case if the property is that of a hidden child with the case ‘*’ being displayed as ‘&’.

Note 2: %n and %t as used by strftime(3) were redundant with \t and \n, respectively, so nothing is lost using them here.

ignoreeof

An option related to dot is ignoreeof which makes mail refuse to accept a ‘control-D’ as the end of a message. If given a numeric argument n, a ‘control-D’ will be accepted after n tries. Ignoreeof also applies to mail command mode.

indentpreamble

If set, this format string will be inserted before quoting a message (~m or ~M). The format syntax is the same as for header-format. For example, the following:

set indentpreamble= 
  "On %b %e %T, %Y %z (%Z), %n (%.50N) wrote:\n-- Subject: %.65q\n"

would insert something like

On Oct 27 11:00:07, 2006 -0400 (EDT), anon (Anon Ymous) wrote: 
-- Subject: suggestions for mail(1)

before the quoted message.

indentprefix

String used by the ~m and ~M tilde escapes for indenting messages, in place of the normal tab character (‘^I’). Be sure to quote the value if it contains spaces or tabs.

indentpostscript

If set, this format string will be inserted after quoting a message (~m or ~M). The format syntax is the same as for header-format. For example, the following:

set indentpostscript="-- End of excerpt from %.50N"

would insert something like

-- End of excerpt from Anon Ymous

after the quoted message.

mime-body-TYPE-SUBTYPE

MIME-hook for the body of a MIME block of ‘Content-Type: TYPE/SUBTYPE’. (See MIME Enhancements below.)

mime-charset

Convert ‘Content-type: text’ messages to this character set or ‘us-ascii’ if the value is empty. If unset, no character set conversion is done.

mime-detach-dir

The directory to detach files to if the detach command is given no arguments. (See detach.)

mime-detach-overwrite

This controls overwriting of existing files by the detach command. If set to ‘ask’ the user will be prompted before overwriting a file. If set to ‘yes’, or to the empty string, existing target files will be overwritten. If set to ‘no’, no target files will be overwritten.

mime-encode-message

If set, encode the body of the message as required. Typically, this is just an issue of whether ‘quoted-printable’ encoding is used or not. If it has a value, then use it to determine the encoding type. Allowed values are ‘7bit’, ‘8bit’, ‘binary’, ‘quoted-printable’, or ‘base64’.

mime-head-TYPE-SUBTYPE

MIME-hook for the header of a MIME block of ‘Content-Type: TYPE/SUBTYPE’. (See MIME Enhancements below.)

mime-hook-TYPE-SUBTYPE

MIME-hook for MIME block of ‘Content-Type: TYPE/SUBTYPE’. (See MIME Enhancements below.)

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.

prompt

If defined, it specifies the prompt to use when in command mode. Otherwise, the default ‘&’ is used. The format syntax is the same as for header-format.

record

If defined, gives the pathname of the file used to record all outgoing mail. If not defined, then outgoing mail is not so saved.

regex-search

If set, regular expression searches are used, instead of simple case insensitive substring matches, when determining message lists by searching sender names, subjects, or header fields (if searchheaders is defined); see the Specifying messages section. The value of the variable is a space or comma delimited list of options. Valid options are ‘icase’ to do case insensitive searches, ‘extended’ to use extended (rather than basic) regular expressions, and ‘nospec’ to turn off all special character meanings and do literal string searches. Note that ‘extended’ and ‘nospec’ are not compatible (see regcomp(3)).

ReplyAsRecipient

This is used when replying to email (see the reply or Reply commands). It is useful if you have multiple email addresses and wish to ensure that replies respect them. If set, grab the email address(es) from the ‘To’ field of the message being replied to. If there is only one such address, and if it does not match any address in the value of ReplyAsRecipient (a comma or space delimited list of addresses, possibly empty), then use this address in the ‘From’ field of the reply. This is accomplished by passing the address to sendmail(1) with the -f option. Note: the sendmail options can be edited with the ~h escape. (See also the smopts command.)

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.

MIME Enhancements

A MIME message is (recursively) divided into a series of MIME parts that can be thought of as sub-messages, each with a header and body. When MIME support is enabled (by setting mime-decode-message), mail splits a message into a series of its smallest MIME parts and processes those parts as if they were messages themselves, passing the header and body through a pipeline of the form:

mail -> MIME-decoder -> MIME-hook -> pager -> screen

The MIME-decoder decodes ‘base64’ or ‘quoted-printable’ encoding and is enabled according to the ‘Content-Transfer-Encoding’ of the part. The MIME-hook is an external program to further process the part (see below). The pager is the program that pages the message (see PAGER). Any of these intermediate pipe stages may be missing and/or different for the head and body of each MIME part. Certain ‘Content-Types’ may disable the entire pipeline (e.g., ‘application/octet’).

The MIME-hook stage is not present unless one of the following variables is set:

mime-hook-TYPE-SUBTYPE    applies to the entire MIME part 
mime-head-TYPE-SUBTYPE    applies to the header of the MIME part 
mime-body-TYPE-SUBTYPE    applies to the body of the MIME part

where TYPE and SUBTYPE are the ‘Content-Type’ type and subtype (respectively) of the MIME part to which the hook applies. If the “-SUBTYPE” is missing, any subtype is matched. The value of these variables has the format:

where the command is expected to read from stdin and write to stdout, and the possible flags are

!

Execute command in a sub-shell rather than doing an exec(3) (see SHELL).

+

Use this hook when selecting the part to display in a ‘multipart/alternative’ block. Multipart blocks contain “alternative” versions with the same information, in increasing order of preference (and decoding complexity). The last one the mail agent understands is the one to be displayed. This is typically used for sending a message in both “plain text” and “html”, but more complex subtypes are also possible.

-

Do not decode before executing command.

If your command begins with one of these flags, precede it with a space to signal the end of the flags.

WARNING: automatically running a program is a potential security risk if that program has bugs, so be careful what you run.

Examples: View all ‘Content-Type: image/jpeg’ parts with xv(1) (assuming it is installed):

set mime-body-image-jpeg="/usr/pkg/bin/xv -"

Decode all ‘Content-Type: images/*’ blocks with uudeview(1) (assuming it is installed), placing the results in /tmp:

set mime-hook-image="-/usr/pkg/bin/uudeview -p /tmp -i -a +o -q -"

Read all ‘Content-Type: text/html’ parts using lynx(1) (assuming it is installed) and add this support to ‘multipart/alternative’ blocks:

set mime-body-text-html="+/usr/pkg/bin/lynx -force_html -dump -stdin"