1 @c This is part of the Emacs manual.
2 @c Copyright (C) 1985, 86, 87, 93, 94, 95, 97, 2000
3 @c Free Software Foundation, Inc.
4 @c See file emacs.texi for copying conditions.
5 @node Sending Mail, Rmail, Picture, Top
11 To send a message in Emacs, you start by typing a command (@kbd{C-x m})
12 to select and initialize the @samp{*mail*} buffer. Then you edit the text
13 and headers of the message in this buffer, and type another command
14 (@kbd{C-c C-s} or @kbd{C-c C-c}) to send the message.
18 Begin composing a message to send (@code{compose-mail}).
20 Likewise, but display the message in another window
21 (@code{compose-mail-other-window}).
23 Likewise, but make a new frame (@code{compose-mail-other-frame}).
25 In Mail mode, send the message (@code{mail-send}).
27 Send the message and bury the mail buffer (@code{mail-send-and-exit}).
33 @findex compose-mail-other-window
35 @findex compose-mail-other-frame
36 The command @kbd{C-x m} (@code{compose-mail}) selects a buffer named
37 @samp{*mail*} and initializes it with the skeleton of an outgoing
38 message. @kbd{C-x 4 m} (@code{compose-mail-other-window}) selects the
39 @samp{*mail*} buffer in a different window, leaving the previous current
40 buffer visible. @kbd{C-x 5 m} (@code{compose-mail-other-frame}) creates
41 a new frame to select the @samp{*mail*} buffer.
43 Because the mail-composition buffer is an ordinary Emacs buffer, you can
44 switch to other buffers while in the middle of composing mail, and switch
45 back later (or never). If you use the @kbd{C-x m} command again when you
46 have been composing another message but have not sent it, you are asked to
47 confirm before the old message is erased. If you answer @kbd{n}, the
48 @samp{*mail*} buffer is left selected with its old contents, so you can
49 finish the old message and send it. @kbd{C-u C-x m} is another way to do
50 this. Sending the message marks the @samp{*mail*} buffer ``unmodified,''
51 which avoids the need for confirmation when @kbd{C-x m} is next used.
53 If you are composing a message in the @samp{*mail*} buffer and want to
54 send another message before finishing the first, rename the
55 @samp{*mail*} buffer using @kbd{M-x rename-uniquely} (@pxref{Misc
56 Buffer}). Then you can use @kbd{C-x m} or its variants described above
57 to make a new @samp{*mail*} buffer. Once you've done that, you can work
58 with each mail buffer independently.
60 @cindex directory servers
63 @cindex names and addresses
64 There is an interface to directory servers using various protocols such
65 as LDAP or the CCSO white pages directory system (PH/QI), described in a
66 separate manual. It may be useful for looking up names and addresses.
67 @xref{Top,,EUDC, eudc, EUDC Manual}.
70 * Format: Mail Format. Format of the mail being composed.
71 * Headers: Mail Headers. Details of permitted mail header fields.
72 * Aliases: Mail Aliases. Abbreviating and grouping mail addresses.
73 * Mode: Mail Mode. Special commands for editing mail being composed.
74 * Spook: Distracting NSA. How to distract the NSA's attention.
75 * Fortune:: `Fortune' items in signatures.
76 * Footnotes: Mail Footnotes. Making footnotes in messages.
77 * Methods: Mail Methods. Using alternative mail-composition methods.
81 @section The Format of the Mail Buffer
83 In addition to the @dfn{text} or @dfn{body}, a message has @dfn{header
84 fields} which say who sent it, when, to whom, why, and so on. Some
85 header fields, such as @samp{Date} and @samp{Sender}, are created
86 automatically when you send the message. Others, such as the recipient
87 names, must be specified by you in order to send the message properly.
89 Mail mode provides a few commands to help you edit some header fields,
90 and some are preinitialized in the buffer automatically at times. You can
91 insert and edit header fields using ordinary editing commands.
93 The line in the buffer that says
96 --text follows this line--
100 is a special delimiter that separates the headers you have specified from
101 the text. Whatever follows this line is the text of the message; the
102 headers precede it. The delimiter line itself does not appear in the
103 message actually sent. The text used for the delimiter line is controlled
104 by the variable @code{mail-header-separator}.
106 Here is an example of what the headers and text in the mail buffer
111 CC: lungfish@@spam.org, byob@@spam.org
112 Subject: The Emacs Manual
113 --Text follows this line--
114 Please ignore this message.
118 @section Mail Header Fields
119 @cindex headers (of mail message)
121 A header field in the mail buffer starts with a field name at the
122 beginning of a line, terminated by a colon. Upper and lower case are
123 equivalent in field names (and in mailing addresses also). After the
124 colon and optional whitespace comes the contents of the field.
126 You can use any name you like for a header field, but normally people
127 use only standard field names with accepted meanings. Here is a table
128 of fields commonly used in outgoing messages.
132 This field contains the mailing addresses to which the message is
133 addressed. If you list more than one address, use commas, not spaces,
137 The contents of the @samp{Subject} field should be a piece of text
138 that says what the message is about. The reason @samp{Subject} fields
139 are useful is that most mail-reading programs can provide a summary of
140 messages, listing the subject of each message but not its text.
143 This field contains additional mailing addresses to send the message to,
144 like @samp{To} except that these readers should not regard the message
148 This field contains additional mailing addresses to send the message to,
149 which should not appear in the header of the message actually sent.
150 Copies sent this way are called @dfn{blind carbon copies}.
152 @vindex mail-self-blind
153 @cindex copy of every outgoing message
154 To send a blind carbon copy of every outgoing message to yourself, set
155 the variable @code{mail-self-blind} to @code{t}. To send a blind carbon
156 copy of every message to some other @var{address}, set the variable
157 @code{mail-default-headers} to @samp{"Bcc: @var{address}\n"}.
160 This field contains the name of one file and directs Emacs to append a
161 copy of the message to that file when you send the message. If the file
162 is in Rmail format, Emacs writes the message in Rmail format; otherwise,
163 Emacs writes the message in system mail file format.
165 @vindex mail-archive-file-name
166 To put a fixed file name in the @samp{FCC} field each time you start
167 editing an outgoing message, set the variable
168 @code{mail-archive-file-name} to that file name. Unless you remove the
169 @samp{FCC} field before sending, the message will be written into that
170 file when it is sent.
173 Use the @samp{From} field to say who you are, when the account you are
174 using to send the mail is not your own. The contents of the @samp{From}
175 field should be a valid mailing address, since replies will normally go
176 there. If you don't specify the @samp{From} field yourself, Emacs uses
177 the value of @code{user-mail-address} as the default.
180 Use this field to direct replies to a different address. Most
181 mail-reading programs (including Rmail) automatically send replies to
182 the @samp{Reply-to} address in preference to the @samp{From} address.
183 By adding a @samp{Reply-to} field to your header, you can work around
184 any problems your @samp{From} address may cause for replies.
186 @cindex @env{REPLYTO} environment variable
187 @vindex mail-default-reply-to
188 To put a fixed @samp{Reply-to} address into every outgoing message, set
189 the variable @code{mail-default-reply-to} to that address (as a string).
190 Then @code{mail} initializes the message with a @samp{Reply-to} field as
191 specified. You can delete or alter that header field before you send
192 the message, if you wish. When Emacs starts up, if the environment
193 variable @env{REPLYTO} is set, @code{mail-default-reply-to} is
194 initialized from that environment variable.
197 This field contains a piece of text describing a message you are
198 replying to. Some mail systems can use this information to correlate
199 related pieces of mail. Normally this field is filled in by Rmail
200 when you reply to a message in Rmail, and you never need to
201 think about it (@pxref{Rmail}).
204 This field lists the message IDs of related previous messages. Rmail
205 sets up this field automatically when you reply to a message.
208 The @samp{To}, @samp{CC}, @samp{BCC} and @samp{FCC} header fields can
209 appear any number of times, and each such header field can contain
210 multiple addresses, separated by commas. This way, you can specify any
211 number of places to send the message. A @samp{To}, @samp{CC}, or
212 @samp{BCC} field can also have continuation lines: one or more lines
213 starting with whitespace, following the starting line of the field, are
214 considered part of the field. Here's an example of a @samp{To} field
215 with a continuation line:@refill
219 To: foo@@here.net, this@@there.net,
220 me@@gnu.cambridge.mass.usa.earth.spiral3281
224 @vindex mail-from-style
225 When you send the message, if you didn't write a @samp{From} field
226 yourself, Emacs puts in one for you. The variable
227 @code{mail-from-style} controls the format:
231 Use just the email address, as in @samp{king@@grassland.com}.
233 Use both email address and full name, as in @samp{king@@grassland.com (Elvis
236 Use both email address and full name, as in @samp{Elvis Parsley
237 <king@@grassland.com>}.
239 Allow the system to insert the @samp{From} field.
242 @vindex mail-default-headers
243 You can force Emacs to insert specific headers into the outgoing
244 message by customizing the variable @code{mail-default-headers}. Its
245 value as a string is inserted before you edit the message.
248 @section Mail Aliases
250 @cindex @file{.mailrc} file
253 You can define @dfn{mail aliases} in a file named @file{~/.mailrc}.
254 These are short mnemonic names which stand for mail addresses or groups of
255 mail addresses. Like many other mail programs, Emacs expands aliases
256 when they occur in the @samp{To}, @samp{From}, @samp{CC}, @samp{BCC}, and
257 @samp{Reply-to} fields, plus their @samp{Resent-} variants.
259 To define an alias in @file{~/.mailrc}, write a line in the following
263 alias @var{shortaddress} @var{fulladdresses}
267 Here @var{fulladdresses} stands for one or more mail addresses for
268 @var{shortaddress} to expand into. Separate multiple addresses with
269 spaces; if an address contains a space, quote the whole address with a
270 pair of double-quotes.
272 For instance, to make @code{maingnu} stand for
273 @code{gnu@@gnu.org} plus a local address of your own, put in
277 alias maingnu gnu@@gnu.org local-gnu
280 Emacs also recognizes include commands in @samp{.mailrc} files.
284 source @var{filename}
288 The file @file{~/.mailrc} is used primarily by other mail-reading
289 programs; it can contain various other commands. Emacs ignores
290 everything in it except for alias definitions and include commands.
292 @findex define-mail-alias
293 Another way to define a mail alias, within Emacs alone, is with the
294 @code{define-mail-alias} command. It prompts for the alias and then the
295 full address. You can use it to define aliases in your @file{.emacs}
299 (define-mail-alias "maingnu" "gnu@@gnu.org")
303 @code{define-mail-alias} records aliases by adding them to a
304 variable named @code{mail-aliases}. If you are comfortable with
305 manipulating Lisp lists, you can set @code{mail-aliases} directly. The
306 initial value of @code{mail-aliases} is @code{t}, which means that
307 Emacs should read @file{.mailrc} to get the proper value.
309 @vindex mail-personal-alias-file
310 You can specify a different file name to use instead of
311 @file{~/.mailrc} by setting the variable
312 @code{mail-personal-alias-file}.
314 @findex expand-mail-aliases
315 Normally, Emacs expands aliases when you send the message. You do not
316 need to expand mail aliases before sending the message, but you can
317 expand them if you want to see where the mail will actually go. To do
318 this, use the command @kbd{M-x expand-mail-aliases}; it expands all mail
319 aliases currently present in the mail headers that hold addresses.
321 If you like, you can have mail aliases expand as abbrevs, as soon as
322 you type them in (@pxref{Abbrevs}). To enable this feature, execute the
326 (add-hook 'mail-mode-hook 'mail-abbrevs-setup)
330 @findex define-mail-abbrev
332 This can go in your @file{.emacs} file. @xref{Hooks}. If you use this
333 feature, you must use @code{define-mail-abbrev} instead of
334 @code{define-mail-alias}; the latter does not work with this package.
335 Note that the mail abbreviation package uses the variable
336 @code{mail-abbrevs} instead of @code{mail-aliases}, and that all alias
337 names are converted to lower case.
339 @kindex C-c C-a @r{(Mail mode)}
340 @findex mail-interactive-insert-alias
341 The mail abbreviation package also provides the @kbd{C-c C-a}
342 (@code{mail-interactive-insert-alias}) command, which reads an alias
343 name (with completion) and inserts its definition at point. This is
344 useful when editing the message text itself or a header field such as
345 @samp{Subject} in which Emacs does not normally expand aliases.
347 Note that abbrevs expand only if you insert a word-separator character
348 afterward. However, you can rebind @kbd{C-n} and @kbd{M->} to cause
349 expansion as well. Here's how to do that:
352 (add-hook 'mail-mode-hook
354 (substitute-key-definition
355 'next-line 'mail-abbrev-next-line
356 mail-mode-map global-map)
357 (substitute-key-definition
358 'end-of-buffer 'mail-abbrev-end-of-buffer
359 mail-mode-map global-map)))
367 The major mode used in the mail buffer is Mail mode, which is much
368 like Text mode except that various special commands are provided on the
369 @kbd{C-c} prefix. These commands all have to do specifically with
370 editing or sending the message. In addition, Mail mode defines the
371 character @samp{%} as a word separator; this is helpful for using the
372 word commands to edit mail addresses.
374 Mail mode is normally used in buffers set up automatically by the
375 @code{mail} command and related commands. However, you can also switch
376 to Mail mode in a file-visiting buffer. That is a useful thing to do if
377 you have saved draft message text in a file.
380 * Mail Sending:: Commands to send the message.
381 * Header Editing:: Commands to move to header fields and edit them.
382 * Citing Mail:: Copying all or part of a message you are replying to.
383 * Mail Mode Misc:: Spell checking, signatures, etc.
387 @subsection Mail Sending
389 Mail mode has two commands for sending the message you have been
394 Send the message, and leave the mail buffer selected (@code{mail-send}).
396 Send the message, and select some other buffer (@code{mail-send-and-exit}).
399 @kindex C-c C-s @r{(Mail mode)}
400 @kindex C-c C-c @r{(Mail mode)}
402 @findex mail-send-and-exit
403 @kbd{C-c C-s} (@code{mail-send}) sends the message and marks the mail
404 buffer unmodified, but leaves that buffer selected so that you can
405 modify the message (perhaps with new recipients) and send it again.
406 @kbd{C-c C-c} (@code{mail-send-and-exit}) sends and then deletes the
407 window or switches to another buffer. It puts the mail buffer at the
408 lowest priority for reselection by default, since you are finished with
409 using it. This is the usual way to send the message.
411 In a file-visiting buffer, sending the message does not clear the
412 modified flag, because only saving the file should do that. As a
413 result, you don't get a warning if you try to send the same message
416 @vindex sendmail-coding-system
417 When you send a message that contains non-ASCII characters, they need
418 to be encoded with a coding system (@pxref{Coding Systems}). Usually
419 the coding system is specified automatically by your chosen language
420 environment (@pxref{Language Environments}). You can explicitly specify
421 the coding system for outgoing mail by setting the variable
422 @code{sendmail-coding-system}.
424 If the coding system thus determined does not handle the characters in
425 a particular message, Emacs asks you to select the coding system to use,
426 showing a list of possible coding systems.
429 @subsection Mail Header Editing
431 Mail mode provides special commands to move to particular header
432 fields and to complete addresses in headers.
436 Move to the @samp{To} header field, creating one if there is none
439 Move to the @samp{Subject} header field, creating one if there is
440 none (@code{mail-subject}).
442 Move to the @samp{CC} header field, creating one if there is none
445 Move to the @samp{BCC} header field, creating one if there is none
448 Move to the @samp{FCC} header field, creating one if there is none
451 Complete a mailing address (@code{mail-complete}).
454 @kindex C-c C-f C-t @r{(Mail mode)}
456 @kindex C-c C-f C-s @r{(Mail mode)}
458 @kindex C-c C-f C-c @r{(Mail mode)}
460 @kindex C-c C-f C-b @r{(Mail mode)}
462 @kindex C-c C-f C-f @r{(Mail mode)}
464 There are five commands to move point to particular header fields, all
465 based on the prefix @kbd{C-c C-f} (@samp{C-f} is for ``field''). They
466 are listed in the table above. If the field in question does not exist,
467 these commands create one. We provide special motion commands for these
468 particular fields because they are the fields users most often want to
471 @findex mail-complete
472 @kindex M-TAB @r{(Mail mode)}
473 While editing a header field that contains mailing addresses, such as
474 @samp{To:}, @samp{CC:} and @samp{BCC:}, you can complete a mailing
475 address by typing @kbd{M-@key{TAB}} (@code{mail-complete}). It inserts
476 the full name corresponding to the address, if it can determine the full
477 name. The variable @code{mail-complete-style} controls whether to insert
478 the full name, and what style to use, as in @code{mail-from-style}
479 (@pxref{Mail Headers}).
481 For completion purposes, the valid mailing addresses are taken to be
482 the local users' names plus your personal mail aliases. You can specify
483 additional sources of valid addresses; use the customization buffer
484 to see the options for this.
486 If you type @kbd{M-@key{TAB}} in the body of the message, it invokes
487 @code{ispell-complete-word}, as in Text mode.
490 @subsection Citing Mail
493 Mail mode also has commands for yanking or @dfn{citing} all or part of
494 a message that you are replying to. These commands are active only when
495 you started sending a message using an Rmail command.
499 Yank the selected message from Rmail (@code{mail-yank-original}).
501 Yank the region from the Rmail buffer (@code{mail-yank-region}).
503 Fill each paragraph cited from another message
504 (@code{mail-fill-yanked-message}).
507 @kindex C-c C-y @r{(Mail mode)}
508 @findex mail-yank-original
509 When mail sending is invoked from the Rmail mail reader using an Rmail
510 command, @kbd{C-c C-y} can be used inside the mail buffer to insert
511 the text of the message you are replying to. Normally it indents each line
512 of that message three spaces and eliminates most header fields. A numeric
513 argument specifies the number of spaces to indent. An argument of just
514 @kbd{C-u} says not to indent at all and not to eliminate anything.
515 @kbd{C-c C-y} always uses the current message from the Rmail buffer,
516 so you can insert several old messages by selecting one in Rmail,
517 switching to @samp{*mail*} and yanking it, then switching back to
518 Rmail to select another.
520 @vindex mail-yank-prefix
521 You can specify the text for @kbd{C-c C-y} to insert at the beginning
522 of each line: set @code{mail-yank-prefix} to the desired string. (A
523 value of @code{nil} means to use indentation; this is the default.)
524 However, @kbd{C-u C-c C-y} never adds anything at the beginning of the
525 inserted lines, regardless of the value of @code{mail-yank-prefix}.
527 @kindex C-c C-r @r{(Mail mode)}
528 @findex mail-yank-region
529 To yank just a part of an incoming message, set the region in Rmail to
530 the part you want; then go to the @samp{*Mail*} message and type
531 @kbd{C-c C-r} (@code{mail-yank-region}). Each line that is copied is
532 indented or prefixed according to @code{mail-yank-prefix}.
534 @kindex C-c C-q @r{(Mail mode)}
535 @findex mail-fill-yanked-message
536 After using @kbd{C-c C-y} or @kbd{C-c C-r}, you can type @kbd{C-c C-q}
537 (@code{mail-fill-yanked-message}) to fill the paragraphs of the yanked
538 old message or messages. One use of @kbd{C-c C-q} fills all such
539 paragraphs, each one individually. To fill a single paragraph of the
540 quoted message, use @kbd{M-q}. If filling does not automatically
541 handle the type of citation prefix you use, try setting the fill prefix
542 explicitly. @xref{Filling}.
545 @subsection Mail Mode Miscellany
549 Move to the beginning of the message body text (@code{mail-text}).
551 Insert the file @file{~/.signature} at the end of the message text
552 (@code{mail-signature}).
553 @item C-c C-i @var{file} @key{RET}
554 Insert the contents of @var{file} at the end of the outgoing message
555 (@code{mail-attach-file}).
556 @item M-x ispell-message
557 Do spelling correction on the message text, but not on citations from
561 @kindex C-c C-t @r{(Mail mode)}
563 @kbd{C-c C-t} (@code{mail-text}) moves point to just after the header
564 separator line---that is, to the beginning of the message body text.
566 @kindex C-c C-w @r{(Mail mode)}
567 @findex mail-signature
568 @vindex mail-signature
569 @kbd{C-c C-w} (@code{mail-signature}) adds a standard piece of text at
570 the end of the message to say more about who you are. The text comes
571 from the file @file{~/.signature} in your home directory. To insert
572 your signature automatically, set the variable @code{mail-signature} to
573 @code{t}; then starting a mail message automatically inserts the
574 contents of your @file{~/.signature} file. If you want to omit your
575 signature from a particular message, delete it from the buffer before
576 you send the message.
578 You can also set @code{mail-signature} to a string; then that string
579 is inserted automatically as your signature when you start editing a
580 message to send. If you set it to some other Lisp expression, the
581 expression is evaluated each time, and its value (which should be a
582 string) specifies the signature.
584 @findex ispell-message
585 You can do spelling correction on the message text you have written
586 with the command @kbd{M-x ispell-message}. If you have yanked an
587 incoming message into the outgoing draft, this command skips what was
588 yanked, but it checks the text that you yourself inserted. (It looks
589 for indentation or @code{mail-yank-prefix} to distinguish the cited
590 lines from your input.) @xref{Spelling}.
592 @kindex C-c C-i @r{(Mail mode)}
593 @findex mail-attach-file
594 To include a file in the outgoing message, you can use @kbd{C-x i},
595 the usual command to insert a file in the current buffer. But it is
596 often more convenient to use a special command, @kbd{C-c C-i}
597 (@code{mail-attach-file}). This command inserts the file contents at
598 the end of the buffer, after your signature if any, with a delimiter
599 line that includes the file name.
601 @vindex mail-mode-hook
602 @vindex mail-setup-hook
603 Turning on Mail mode (which @kbd{C-x m} does automatically) runs the
604 normal hooks @code{text-mode-hook} and @code{mail-mode-hook}.
605 Initializing a new outgoing message runs the normal hook
606 @code{mail-setup-hook}; if you want to add special fields to your mail
607 header or make other changes to the appearance of the mail buffer, use
608 that hook. @xref{Hooks}.
610 The main difference between these hooks is just when they are
611 invoked. Whenever you type @kbd{M-x mail}, @code{mail-mode-hook} runs
612 as soon as the @samp{*mail*} buffer is created. Then the
613 @code{mail-setup} function puts in the default contents of the buffer.
614 After these default contents are inserted, @code{mail-setup-hook} runs.
616 @node Distracting NSA
617 @section Distracting the NSA
621 @kbd{M-x spook} adds a line of randomly chosen keywords to an outgoing
622 mail message. The keywords are chosen from a list of words that suggest
623 you are discussing something subversive.
625 The idea behind this feature is the suspicion that the
626 NSA@footnote{The US National Security Agency.} snoops on
627 all electronic mail messages that contain keywords suggesting they might
628 find them interesting. (The NSA says they don't, but that's what they
629 @emph{would} say.) The idea is that if lots of people add suspicious
630 words to their messages, the NSA will get so busy with spurious input
631 that they will have to give up reading it all.
633 Here's how to insert spook keywords automatically whenever you start
634 entering an outgoing message:
637 (setq mail-signature '(spook))
640 Whether or not this confuses the NSA, it at least amuses people.
643 @section Putting @code{fortune} Items in Signatures
646 @findex fortune-to-signature
647 @findex fortune-from-region
648 @cindex signatures, mail/news
649 @cindex fortune cookies
650 You can use the @code{fortune} program to create signatures for mail or
651 network news messages. (@code{fortune} prints a random---with luck,
652 interesting---adage, originally inspired by `fortune cookie' messages.)
653 To generate signatures, add @code{fortune-to-signature} to
654 @code{mail-setup-hook} and/or @code{message-setup-hook} as appropriate.
655 You can automatically cut regions to a Fortune file with @kbd{M-x
656 fortune-from-region} and compile your own Fortune database.
659 @section Making Footnotes
662 @findex footnote-mode
663 @kbd{M-x footnote-mode} toggles a minor mode for making footnotes in
664 mail or network news messages. It is intended for use specifically with
665 Message mode but is not specific to that. It provides commands and
666 keybindings to insert footnotes, go to a given note, delete a note and
667 renumber notes. See the group @code{footnote} for customization and the
668 mode's documentation for keybindings. To set up Footnote mode for all
669 messages, add @code{footnote-mode} to @code{mail-mode-hook} and/or
670 @code{message-mode-hook} as appropriate.
673 @section Mail-Composition Methods
674 @cindex mail-composition methods
676 This chapter describes the usual Emacs mode for editing and sending
677 mail---Mail mode. Emacs has alternative facilities for editing and
678 sending mail, including
679 @cindex MH mail interface
680 @cindex Message mode for sending mail
681 MH-E and Message mode, not documented in this manual.
682 @xref{,MH-E,,mh-e, The Emacs Interface to MH}. @xref{,Message,,message,
683 Message Manual}. You can choose any of them as your preferred method.
684 The commands @code{C-x m}, @code{C-x 4 m} and @code{C-x 5 m} use
685 whichever agent you have specified. So do various other Emacs commands
686 and facilities that send mail.
688 @vindex mail-user-agent
689 To specify your mail-composition method, customize the variable
690 @code{mail-user-agent}. Currently legitimate values include
691 @code{sendmail-user-agent}, @code{mh-e-user-agent},
692 @code{message-user-agent} and @code{gnus-user-agent}.
694 If you select a different mail-composition method, the information in
695 this chapter about the @samp{*mail*} buffer and Mail mode does not
696 necessarily apply; other methods may use completely different commands
697 with a different format in a differently named buffer.