gnus: Posting Styles
5.6 Posting Styles
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All them variables, they make my head swim.
So what if you want a different ‘Organization’ and signature based on
what groups you post to? And you post both from your home machine and
your work machine, and you want different ‘From’ lines, and so on?
One way to do stuff like that is to write clever hooks that change
the variables you need to have changed. That’s a bit boring, so
somebody came up with the bright idea of letting the user specify these
things in a handy alist. Here’s an example of a ‘gnus-posting-styles’
variable:
((".*"
(signature "Peace and happiness")
(organization "What me?"))
("^comp"
(signature "Death to everybody"))
("comp.emacs.i-love-it"
(organization "Emacs is it")))
As you might surmise from this example, this alist consists of
several “styles”. Each style will be applicable if the first element
“matches”, in some form or other. The entire alist will be iterated
over, from the beginning towards the end, and each match will be
applied, which means that attributes in later styles that match override
the same attributes in earlier matching styles. So
‘comp.programming.literate’ will have the ‘Death to everybody’ signature
and the ‘What me?’ ‘Organization’ header.
The first element in each style is called the ‘match’. If it’s a
string, then Gnus will try to regexp match it against the group name.
If it is the form ‘(header MATCH REGEXP)’, then Gnus will look in the
original article for a header whose name is MATCH and compare that
REGEXP. MATCH and REGEXP are strings. (The original article is the one
you are replying or following up to. If you are not composing a reply
or a followup, then there is nothing to match against.) If the ‘match’
is a function symbol, that function will be called with no arguments.
If it’s a variable symbol, then the variable will be referenced. If
it’s a list, then that list will be ‘eval’ed. In any case, if this
returns a non-‘nil’ value, then the style is said to “match”.
Each style may contain an arbitrary amount of “attributes”. Each
attribute consists of a ‘(NAME VALUE)’ pair. In addition, you can also
use the ‘(NAME :file VALUE)’ form or the ‘(NAME :value VALUE)’ form.
Where ‘:file’ signifies VALUE represents a file name and its contents
should be used as the attribute value, ‘:value’ signifies VALUE does not
represent a file name explicitly. The attribute name can be one of:
• ‘signature’
• ‘signature-file’
• ‘x-face-file’
• ‘address’, overriding ‘user-mail-address’
• ‘name’, overriding ‘(user-full-name)’
• ‘body’
Note that the ‘signature-file’ attribute honors the variable
‘message-signature-directory’.
The attribute name can also be a string or a symbol. In that case,
this will be used as a header name, and the value will be inserted in
the headers of the article; if the value is ‘nil’, the header name will
be removed. If the attribute name is ‘eval’, the form is evaluated, and
the result is thrown away.
The attribute value can be a string, a function with zero arguments
(the return value will be used), a variable (its value will be used) or
a list (it will be ‘eval’ed and the return value will be used). The
functions and sexps are called/‘eval’ed in the message buffer that is
being set up. The headers of the current article are available through
the ‘message-reply-headers’ variable, which is a vector of the following
headers: number subject from date id references chars lines xref extra.
In the case of a string value, if the ‘match’ is a regular
expression, or if it takes the form ‘(header MATCH REGEXP)’, a
‘gnus-match-substitute-replacement’ is proceed on the value to replace
the positional parameters ‘\N’ by the corresponding parenthetical
matches (see 
Replacing the Text that Matched (elisp)Replacing
Match.)
If you wish to check whether the message you are about to compose is
meant to be a news article or a mail message, you can check the values
of the ‘message-news-p’ and ‘message-mail-p’ functions.
So here’s a new example:
(setq gnus-posting-styles
'((".*"
(signature-file "~/.signature")
(name "User Name")
(x-face-file "~/.xface")
(x-url (getenv "WWW_HOME"))
(organization "People's Front Against MWM"))
("^rec.humor"
(signature my-funny-signature-randomizer))
((equal (system-name) "gnarly") ;; A form
(signature my-quote-randomizer))
(message-news-p ;; A function symbol
(signature my-news-signature))
(window-system ;; A value symbol
("X-Window-System" (format "%s" window-system)))
;; If I’m replying to Larsi, set the Organization header.
((header "from" "larsi.*org")
(Organization "Somewhere, Inc."))
;; Reply to a message from the same subaddress the message
;; was sent to.
((header "x-original-to" "me\\(\\+.+\\)@example.org")
(address "me\\1@example.org"))
((posting-from-work-p) ;; A user defined function
(signature-file "~/.work-signature")
(address "user@bar.foo")
(body "You are fired.\n\nSincerely, your boss.")
("X-Message-SMTP-Method" "smtp smtp.example.org 587")
(organization "Important Work, Inc"))
("nnml:.*"
(From (with-current-buffer gnus-article-buffer
(message-fetch-field "to"))))
("^nn.+:"
(signature-file "~/.mail-signature"))))
The ‘nnml:.*’ rule means that you use the ‘To’ address as the ‘From’
address in all your outgoing replies, which might be handy if you fill
many roles. You may also use ‘message-alternative-emails’ instead.
Message Headers (message)Message Headers.
Of particular interest in the “work-mail” style is the
‘X-Message-SMTP-Method’ header. It specifies how to send the outgoing
email. You may want to sent certain emails through certain SMTP servers
due to company policies, for instance. Message Variables
(message)Mail Variables.
Info Catalog
gnus: Archived Messages
gnus: Composing Messages
gnus: Drafts