The Gnus Newsreader
*******************

You can read news (and mail) from within Emacs by using Gnus.  The news can be gotten by any nefarious means you can think of---NNTP, local spool or your mbox file.  All at the same time, if you want to push your luck.

This manual corresponds to No Gnus v0.11.

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Starting Gnus
*************

If you haven't used Emacs much before using Gnus, read Emacs for Heathens first.

If your system administrator has set things up properly, starting Gnus and reading news is extremely easy---you just type M-x gnus in your Emacs.  If not, you should customize the variable gnus-select-method as described in Finding the News.  For a minimal setup for posting should also customize the variables user-full-name and user-mail-address.

If you want to start Gnus in a different frame, you can use the command M-x gnus-other-frame instead.

If things do not go smoothly at startup, you have to twiddle some variables in your ~/.gnus.el file.  This file is similar to ~/.emacs, but is read when Gnus starts.

If you puzzle at any terms used in this manual, please refer to the terminology section (see Terminology).

Finding the News
================

First of all, you should know that there is a special buffer called *Server* that lists all the servers Gnus knows about.  You can press ^ from the Group buffer to see it.  In the Server buffer, you can press RET on a defined server to see all the groups it serves (subscribed or not!).  You can also add or delete servers, edit a foreign server's definition, agentize or de-agentize a server, and do many other neat things.  See Server Buffer. See Foreign Groups.  See Agent Basics.

The gnus-select-method variable says where Gnus should look for news.  This variable should be a list where the first element says how and the second element says where.  This method is your native method.  All groups not fetched with this method are foreign groups.

For instance, if the news.somewhere.edu NNTP server is where you want to get your daily dosage of news from, you'd say:

     (setq gnus-select-method '(nntp "news.somewhere.edu"))

If you want to read directly from the local spool, say:

     (setq gnus-select-method '(nnspool ""))

If you can use a local spool, you probably should, as it will almost certainly be much faster.  But do not use the local spool if your server is running Leafnode (which is a simple, standalone private news server); in this case, use (nntp "localhost").

If this variable is not set, Gnus will take a look at the NNTPSERVER environment variable.  If that variable isn't set, Gnus will see whether gnus-nntpserver-file (/etc/nntpserver by default) has any opinions on the matter. If that fails as well, Gnus will try to use the machine running Emacs as an NNTP server.  That's a long shot, though.

However, if you use one NNTP server regularly and are just interested in a couple of groups from a different server, you would be better served by using the B command in the group buffer.  It will let you have a look at what groups are available, and you can subscribe to any of the groups you want to.  This also makes .newsrc maintenance much tidier.  See Foreign Groups.

A slightly different approach to foreign groups is to set the gnus-secondary-select-methods variable.  The select methods listed in this variable are in many ways just as native as the gnus-select-method server.  They will also be queried for active files during startup (if that's required), and new newsgroups that appear on these servers will be subscribed (or not) just as native groups are.

For instance, if you use the nnmbox back end to read your mail, you would typically set this variable to

     (setq gnus-secondary-select-methods '((nnmbox "")))

Note: the NNTP back end stores marks in marks files (see NNTP marks).  This feature makes it easy to share marks between several Gnus installations, but may slow down things a bit when fetching new articles.  See NNTP marks, for more information.

The First Time
==============

If no startup files exist (see Startup Files), Gnus will try to determine what groups should be subscribed by default.

If the variable gnus-default-subscribed-newsgroups is set, Gnus will subscribe you to just those groups in that list, leaving the rest killed.  Your system administrator should have set this variable to something useful.

Since she hasn't, Gnus will just subscribe you to a few arbitrarily picked groups (i.e., *.newusers).  (Arbitrary is defined here as whatever Lars thinks you should read.)

You'll also be subscribed to the Gnus documentation group, which should help you with most common problems.

If gnus-default-subscribed-newsgroups is t, Gnus will just use the normal functions for handling new groups, and not do anything special.

The Server is Down
==================

If the default server is down, Gnus will understandably have some problems starting.  However, if you have some mail groups in addition to the news groups, you may want to start Gnus anyway.

Gnus, being the trusting sort of program, will ask whether to proceed without a native select method if that server can't be contacted.  This will happen whether the server doesn't actually exist (i.e., you have given the wrong address) or the server has just momentarily taken ill for some reason or other.  If you decide to continue and have no foreign groups, you'll find it difficult to actually do anything in the group buffer.  But, hey, that's your problem.  Blllrph!

If you know that the server is definitely down, or you just want to read your mail without bothering with the server at all, you can use the gnus-no-server command to start Gnus.  That might come in handy if you're in a hurry as well.  This command will not attempt to contact your primary server---instead, it will just activate all groups on level 1 and 2.  (You should preferably keep no native groups on those two levels.) Also see Group Levels.

Slave Gnusae
============

You might want to run more than one Emacs with more than one Gnus at the same time.  If you are using different .newsrc files (e.g., if you are using the two different Gnusae to read from two different servers), that is no problem whatsoever.  You just do it.

The problem appears when you want to run two Gnusae that use the same .newsrc file.

To work around that problem some, we here at the Think-Tank at the Gnus Towers have come up with a new concept: Masters and slaves.  (We have applied for a patent on this concept, and have taken out a copyright on those words.  If you wish to use those words in conjunction with each other, you have to send $1 per usage instance to me.  Usage of the patent (Master/Slave Relationships In Computer Applications) will be much more expensive, of course.)

Anyway, you start one Gnus up the normal way with M-x gnus (or however you do it).  Each subsequent slave Gnusae should be started with M-x gnus-slave.  These slaves won't save normal .newsrc files, but instead save slave files that contain information only on what groups have been read in the slave session.  When a master Gnus starts, it will read (and delete) these slave files, incorporating all information from them.  (The slave files will be read in the sequence they were created, so the latest changes will have precedence.)

Information from the slave files has, of course, precedence over the information in the normal (i.e., master) .newsrc file.

If the .newsrc* files have not been saved in the master when the slave starts, you may be prompted as to whether to read an auto-save file.  If you answer ``yes'', the unsaved changes to the master will be incorporated into the slave.  If you answer ``no'', the slave may see some messages as unread that have been read in the master.

New Groups
==========

If you are satisfied that you really never want to see any new groups, you can set gnus-check-new-newsgroups to nil.  This will also save you some time at startup.  Even if this variable is nil, you can always subscribe to the new groups just by pressing U in the group buffer (see Group Maintenance).  This variable is ask-server by default.  If you set this variable to always, then Gnus will query the back ends for new groups even when you do the g command (see Scanning New Messages).

Checking New Groups
-------------------

Gnus normally determines whether a group is new or not by comparing the list of groups from the active file(s) with the lists of subscribed and dead groups.  This isn't a particularly fast method.  If gnus-check-new-newsgroups is ask-server, Gnus will ask the server for new groups since the last time.  This is both faster and cheaper.  This also means that you can get rid of the list of killed groups altogether, so you may set gnus-save-killed-list to nil, which will save time both at startup, at exit, and all over. Saves disk space, too.  Why isn't this the default, then? Unfortunately, not all servers support this command.

I bet I know what you're thinking now: How do I find out whether my server supports ask-server?  No?  Good, because I don't have a fail-safe answer.  I would suggest just setting this variable to ask-server and see whether any new groups appear within the next few days.  If any do, then it works.  If none do, then it doesn't work.  I could write a function to make Gnus guess whether the server supports ask-server, but it would just be a guess.  So I won't. You could telnet to the server and say HELP and see whether it lists NEWGROUPS among the commands it understands.  If it does, then it might work.  (But there are servers that lists NEWGROUPS without supporting the function properly.)

This variable can also be a list of select methods.  If so, Gnus will issue an ask-server command to each of the select methods, and subscribe them (or not) using the normal methods.  This might be handy if you are monitoring a few servers for new groups.  A side effect is that startup will take much longer, so you can meditate while waiting. Use the mantra ``dingnusdingnusdingnus'' to achieve permanent bliss.

Subscription Methods
--------------------

What Gnus does when it encounters a new group is determined by the gnus-subscribe-newsgroup-method variable.

This variable should contain a function.  This function will be called with the name of the new group as the only parameter.

Some handy pre-fab functions are:

gnus-subscribe-zombies
     Make all new groups zombies.  This is the default.  You can browse the zombies later (with A z) and either kill them all off properly (with S z), or subscribe to them (with u).

gnus-subscribe-randomly
     Subscribe all new groups in arbitrary order.  This really means that all new groups will be added at ``the top'' of the group buffer.

gnus-subscribe-alphabetically
     Subscribe all new groups in alphabetical order.

gnus-subscribe-hierarchically
     Subscribe all new groups hierarchically.  The difference between this function and gnus-subscribe-alphabetically is slight. gnus-subscribe-alphabetically will subscribe new groups in a strictly alphabetical fashion, while this function will enter groups into its hierarchy.  So if you want to have the rec hierarchy before the comp hierarchy, this function will not mess that configuration up.  Or something like that.

gnus-subscribe-interactively
     Subscribe new groups interactively.  This means that Gnus will ask you about all new groups.  The groups you choose to subscribe to will be subscribed hierarchically.

gnus-subscribe-killed
     Kill all new groups.

gnus-subscribe-topics
     Put the groups into the topic that has a matching subscribe topic parameter (see Topic Parameters).  For instance, a subscribe topic parameter that looks like

          "nnml"

     will mean that all groups that match that regex will be subscribed under that topic.

     If no topics match the groups, the groups will be subscribed in the top-level topic.

A closely related variable is gnus-subscribe-hierarchical-interactive.  (That's quite a mouthful.)  If this variable is non-nil, Gnus will ask you in a hierarchical fashion whether to subscribe to new groups or not.  Gnus will ask you for each sub-hierarchy whether you want to descend the hierarchy or not.

One common mistake is to set the variable a few paragraphs above (gnus-subscribe-newsgroup-method) to gnus-subscribe-hierarchical-interactive.  This is an error.  This will not work.  This is ga-ga.  So don't do it.

Filtering New Groups
--------------------

A nice and portable way to control which new newsgroups should be subscribed (or ignored) is to put an options line at the start of the .newsrc file.  Here's an example:

     options -n !alt.all !rec.all sci.all

This line obviously belongs to a serious-minded intellectual scientific person (or she may just be plain old boring), because it says that all groups that have names beginning with alt and rec should be ignored, and all groups with names beginning with sci should be subscribed.  Gnus will not use the normal subscription method for subscribing these groups. gnus-subscribe-options-newsgroup-method is used instead.  This variable defaults to gnus-subscribe-alphabetically.

If you don't want to mess with your .newsrc file, you can just set the two variables gnus-options-subscribe and gnus-options-not-subscribe.  These two variables do exactly the same as the .newsrc options -n trick.  Both are regexps, and if the new group matches the former, it will be unconditionally subscribed, and if it matches the latter, it will be ignored.

Yet another variable that meddles here is gnus-auto-subscribed-groups.  It works exactly like gnus-options-subscribe, and is therefore really superfluous, but I thought it would be nice to have two of these.  This variable is more meant for setting some ground rules, while the other variable is used more for user fiddling.  By default this variable makes all new groups that come from mail back ends (nnml, nnbabyl, nnfolder, nnmbox, nnmh, and nnmaildir) subscribed.  If you don't like that, just set this variable to nil.

New groups that match this regexp are subscribed using gnus-subscribe-options-newsgroup-method.

Changing Servers
================

Sometimes it is necessary to move from one NNTP server to another. This happens very rarely, but perhaps you change jobs, or one server is very flaky and you want to use another.

Changing the server is pretty easy, right?  You just change gnus-select-method to point to the new server?

Wrong!

Article numbers are not (in any way) kept synchronized between different NNTP servers, and the only way Gnus keeps track of what articles you have read is by keeping track of article numbers.  So when you change gnus-select-method, your .newsrc file becomes worthless.

You can use the M-x gnus-group-clear-data-on-native-groups command to clear out all data that you have on your native groups. Use with caution.

Clear the data from the current group only---nix out marks and the list of read articles (gnus-group-clear-data).

After changing servers, you must move the cache hierarchy away, since the cached articles will have wrong article numbers, which will affect which articles Gnus thinks are read. gnus-group-clear-data-on-native-groups will ask you if you want to have it done automatically; for gnus-group-clear-data, you can use M-x gnus-cache-move-cache (but beware, it will move the cache for all groups).

Startup Files
=============

Most common Unix news readers use a shared startup file called .newsrc.  This file contains all the information about what groups are subscribed, and which articles in these groups have been read.

Things got a bit more complicated with GNUS.  In addition to keeping the .newsrc file updated, it also used a file called .newsrc.el for storing all the information that didn't fit into the .newsrc file.  (Actually, it also duplicated everything in the .newsrc file.)  GNUS would read whichever one of these files was the most recently saved, which enabled people to swap between GNUS and other newsreaders.

That was kinda silly, so Gnus went one better: In addition to the .newsrc and .newsrc.el files, Gnus also has a file called .newsrc.eld.  It will read whichever of these files that are most recent, but it will never write a .newsrc.el file.  You should never delete the .newsrc.eld file---it contains much information not stored in the .newsrc file.

You can turn off writing the .newsrc file by setting gnus-save-newsrc-file to nil, which means you can delete the file and save some space, as well as exiting from Gnus faster. However, this will make it impossible to use other newsreaders than Gnus.  But hey, who would want to, right?  Similarly, setting gnus-read-newsrc-file to nil makes Gnus ignore the .newsrc file and any .newsrc-SERVER files, which can be convenient if you use a different news reader occasionally, and you want to read a different subset of the available groups with that news reader.

If gnus-save-killed-list (default t) is nil, Gnus will not save the list of killed groups to the startup file.  This will save both time (when starting and quitting) and space (on disk).  It will also mean that Gnus has no record of what groups are new or old, so the automatic new groups subscription methods become meaningless. You should always set gnus-check-new-newsgroups to nil or ask-server if you set this variable to nil (see New Groups).  This variable can also be a regular expression.  If that's the case, remove all groups that do not match this regexp before saving.  This can be useful in certain obscure situations that involve several servers where not all servers support ask-server.

The gnus-startup-file variable says where the startup files are. The default value is ~/.newsrc, with the Gnus (El Dingo) startup file being whatever that one is, with a .eld appended. If you want version control for this file, set gnus-backup-startup-file.  It respects the same values as the version-control variable.

gnus-save-newsrc-hook is called before saving any of the newsrc files, while gnus-save-quick-newsrc-hook is called just before saving the .newsrc.eld file, and gnus-save-standard-newsrc-hook is called just before saving the .newsrc file.  The latter two are commonly used to turn version control on or off.  Version control is on by default when saving the startup files.  If you want to turn backup creation off, say something like:

     (defun turn-off-backup ()
       (set (make-local-variable 'backup-inhibited) t))

     (add-hook 'gnus-save-quick-newsrc-hook 'turn-off-backup)
     (add-hook 'gnus-save-standard-newsrc-hook 'turn-off-backup)

When Gnus starts, it will read the gnus-site-init-file (.../site-lisp/gnus-init by default) and gnus-init-file (~/.gnus by default) files.  These are normal Emacs Lisp files and can be used to avoid cluttering your ~/.emacs and site-init files with Gnus stuff.  Gnus will also check for files with the same names as these, but with .elc and .el suffixes.  In other words, if you have set gnus-init-file to ~/.gnus, it will look for ~/.gnus.elc, ~/.gnus.el, and finally ~/.gnus (in this order).  If Emacs was invoked with the -q or --no-init-file options (see Initial Options (The Emacs Manual)), Gnus doesn't read gnus-init-file.

Auto Save
=========

Whenever you do something that changes the Gnus data (reading articles, catching up, killing/subscribing groups), the change is added to a special dribble buffer.  This buffer is auto-saved the normal Emacs way.  If your Emacs should crash before you have saved the .newsrc files, all changes you have made can be recovered from this file.

If Gnus detects this file at startup, it will ask the user whether to read it.  The auto save file is deleted whenever the real startup file is saved.

If gnus-use-dribble-file is nil, Gnus won't create and maintain a dribble buffer.  The default is t.

Gnus will put the dribble file(s) in gnus-dribble-directory.  If this variable is nil, which it is by default, Gnus will dribble into the directory where the .newsrc file is located.  (This is normally the user's home directory.)  The dribble file will get the same file permissions as the .newsrc file.

If gnus-always-read-dribble-file is non-nil, Gnus will read the dribble file on startup without querying the user.

The Active File
===============

When Gnus starts, or indeed whenever it tries to determine whether new articles have arrived, it reads the active file.  This is a very large file that lists all the active groups and articles on the server.

Before examining the active file, Gnus deletes all lines that match the regexp gnus-ignored-newsgroups.  This is done primarily to reject any groups with bogus names, but you can use this variable to make Gnus ignore hierarchies you aren't ever interested in.  However, this is not recommended.  In fact, it's highly discouraged.  Instead, see New Groups for an overview of other variables that can be used instead.

The active file can be rather Huge, so if you have a slow network, you can set gnus-read-active-file to nil to prevent Gnus from reading the active file.  This variable is some by default.

Gnus will try to make do by getting information just on the groups that you actually subscribe to.

Note that if you subscribe to lots and lots of groups, setting this variable to nil will probably make Gnus slower, not faster.  At present, having this variable nil will slow Gnus down considerably, unless you read news over a 2400 baud modem.

This variable can also have the value some.  Gnus will then attempt to read active info only on the subscribed groups.  On some servers this is quite fast (on sparkling, brand new INN servers that support the LIST ACTIVE group command), on others this isn't fast at all.  In any case, some should be faster than nil, and is certainly faster than t over slow lines.

Some news servers (old versions of Leafnode and old versions of INN, for instance) do not support the LIST ACTIVE group.  For these servers, nil is probably the most efficient value for this variable.

If this variable is nil, Gnus will ask for group info in total lock-step, which isn't very fast.  If it is some and you use an NNTP server, Gnus will pump out commands as fast as it can, and read all the replies in one swoop.  This will normally result in better performance, but if the server does not support the aforementioned LIST ACTIVE group command, this isn't very nice to the server.

If you think that starting up Gnus takes too long, try all the three different values for this variable and see what works best for you.

In any case, if you use some or nil, you should definitely kill all groups that you aren't interested in to speed things up.

Note that this variable also affects active file retrieval from secondary select methods.

Startup Variables
=================

gnus-load-hook
     A hook run while Gnus is being loaded.  Note that this hook will normally be run just once in each Emacs session, no matter how many times you start Gnus.

gnus-before-startup-hook
     A hook called as the first thing when Gnus is started.

gnus-startup-hook
     A hook run as the very last thing after starting up Gnus

gnus-started-hook
     A hook that is run as the very last thing after starting up Gnus successfully.

gnus-setup-news-hook
     A hook that is run after reading the .newsrc file(s), but before generating the group buffer.

gnus-check-bogus-newsgroups
     If non-nil, Gnus will check for and delete all bogus groups at startup.  A bogus group is a group that you have in your .newsrc file, but doesn't exist on the news server.  Checking for bogus groups can take quite a while, so to save time and resources it's best to leave this option off, and do the checking for bogus groups once in a while from the group buffer instead (see Group Maintenance).

gnus-inhibit-startup-message
     If non-nil, the startup message won't be displayed.  That way, your boss might not notice as easily that you are reading news instead of doing your job.  Note that this variable is used before ~/.gnus.el is loaded, so it should be set in .emacs instead.

gnus-no-groups-message
     Message displayed by Gnus when no groups are available.

gnus-use-backend-marks
     If non-nil, Gnus will store article marks both in the .newsrc.eld file and in the backends.  This will slow down group operation some.

Group Buffer
************

The group buffer lists all (or parts) of the available groups.  It is the first buffer shown when Gnus starts, and will never be killed as long as Gnus is active.

Group Buffer Format
===================

You can customize the Group Mode tool bar, see M-x customize-apropos RET gnus-group-tool-bar.  This feature is only available in Emacs.

The tool bar icons are now (de)activated correctly depending on the cursor position.  Therefore, moving around in the Group Buffer is slower.  You can disable this via the variable gnus-group-update-tool-bar.  Its default value depends on your Emacs version.

Group Line Specification
------------------------

The default format of the group buffer is nice and dull, but you can make it as exciting and ugly as you feel like.

Here's a couple of example group lines:

          25: news.announce.newusers
      *    0: alt.fan.andrea-dworkin

Quite simple, huh?

You can see that there are 25 unread articles in news.announce.newusers.  There are no unread articles, but some ticked articles, in alt.fan.andrea-dworkin (see that little asterisk at the beginning of the line?).

You can change that format to whatever you want by fiddling with the gnus-group-line-format variable.  This variable works along the lines of a format specification, which is pretty much the same as a printf specifications, for those of you who use (feh!) C. See Formatting Variables.

%M%S%5y:%B%(%g%)\n is the value that produced those lines above.

There should always be a colon on the line; the cursor always moves to the colon after performing an operation.  See Positioning Point.  Nothing else is required---not even the group name.  All displayed text is just window dressing, and is never examined by Gnus. Gnus stores all real information it needs using text properties.

(Note that if you make a really strange, wonderful, spreadsheet-like layout, everybody will believe you are hard at work with the accounting instead of wasting time reading news.)

Here's a list of all available format characters:

M
     An asterisk if the group only has marked articles.

S
     Whether the group is subscribed.

L
     Level of subscribedness.

N
     Number of unread articles.

I
     Number of dormant articles.

T
     Number of ticked articles.

R
     Number of read articles.

U
     Number of unseen articles.

t
     Estimated total number of articles.  (This is really MAX-NUMBER minus MIN-NUMBER plus 1.)

     Gnus uses this estimation because the NNTP protocol provides efficient access to MAX-NUMBER and MIN-NUMBER but getting the true unread message count is not possible efficiently.  For hysterical raisins, even the mail back ends, where the true number of unread messages might be available efficiently, use the same limited interface.  To remove this restriction from Gnus means that the back end interface has to be changed, which is not an easy job.

     The nnml backend (see Mail Spool) has a feature called ``group compaction'' which circumvents this deficiency: the idea is to renumber all articles from 1, removing all gaps between numbers, hence getting a correct total count.  Other backends may support this in the future.  In order to keep your total article count relatively up to date, you might want to compact your groups (or even directly your server) from time to time. See Misc Group Stuff, see Server Commands.

y
     Number of unread, unticked, non-dormant articles.

i
     Number of ticked and dormant articles.

g
     Full group name.

G
     Group name.

C
     Group comment (see Group Parameters) or group name if there is no comment element in the group parameters.

D
     Newsgroup description.  You need to read the group descriptions before these will appear, and to do that, you either have to set gnus-read-active-file or use the group buffer M-d command.

o
     m if moderated.

O
     (m) if moderated.

s
     Select method.

B
     If the summary buffer for the group is open or not.

n
     Select from where.

z
     A string that looks like <%s:%n> if a foreign select method is used.

P
     Indentation based on the level of the topic (see Group Topics).

c
     Short (collapsed) group name.  The gnus-group-uncollapsed-levels variable says how many levels to leave at the end of the group name. The default is 1---this will mean that group names like gnu.emacs.gnus will be shortened to g.e.gnus.

m
     % (gnus-new-mail-mark) if there has arrived new mail to the group lately.

p
     # (gnus-process-mark) if the group is process marked.

d
     A string that says when you last read the group (see Group Timestamp).

F
     The disk space used by the articles fetched by both the cache and agent.  The value is automatically scaled to bytes(B), kilobytes(K), megabytes(M), or gigabytes(G) to minimize the column width.  A format of %7F is sufficient for a fixed-width column.

u
     User defined specifier.  The next character in the format string should be a letter.  Gnus will call the function gnus-user-format-function-X, where X is the letter following %u.  The function will be passed a single dummy parameter as argument.  The function should return a string, which will be inserted into the buffer just like information from any other specifier.

All the ``number-of'' specs will be filled with an asterisk (*) if no info is available---for instance, if it is a non-activated foreign group, or a bogus native group.

Group Mode Line Specification
-----------------------------

The mode line can be changed by setting gnus-group-mode-line-format (see Mode Line Formatting).  It doesn't understand that many format specifiers:

S
     The native news server.

M
     The native select method.

Group Highlighting
------------------

Highlighting in the group buffer is controlled by the gnus-group-highlight variable.  This is an alist with elements that look like (FORM . FACE).  If FORM evaluates to something non-nil, the FACE will be used on the line.

Here's an example value for this variable that might look nice if the background is dark:

     (cond (window-system
            (setq custom-background-mode 'light)
            (defface my-group-face-1
              '((t (:foreground "Red" :bold t))) "First group face")
            (defface my-group-face-2
              '((t (:foreground "DarkSeaGreen4" :bold t)))
              "Second group face")
            (defface my-group-face-3
              '((t (:foreground "Green4" :bold t))) "Third group face")
            (defface my-group-face-4
              '((t (:foreground "SteelBlue" :bold t))) "Fourth group face")
            (defface my-group-face-5
              '((t (:foreground "Blue" :bold t))) "Fifth group face")))

     (setq gnus-group-highlight
           '(((> unread 200) . my-group-face-1)
             ((and (< level 3) (zerop unread)) . my-group-face-2)
             ((< level 3) . my-group-face-3)
             ((zerop unread) . my-group-face-4)
             (t . my-group-face-5)))

Also see Faces and Fonts.

Variables that are dynamically bound when the forms are evaluated include:

group
     The group name.

unread
     The number of unread articles in the group.

method
     The select method.

mailp
     Whether the group is a mail group.

level
     The level of the group.

score
     The score of the group.

ticked
     The number of ticked articles in the group.

total
     The total number of articles in the group.  Or rather, MAX-NUMBER minus MIN-NUMBER plus one.

topic
     When using the topic minor mode, this variable is bound to the current topic being inserted.

When the forms are evaled, point is at the beginning of the line of the group in question, so you can use many of the normal Gnus functions for snarfing info on the group.

gnus-group-update-hook is called when a group line is changed. It will not be called when gnus-visual is nil.

Group Maneuvering
=================

All movement commands understand the numeric prefix and will behave as expected, hopefully.

n
     Go to the next group that has unread articles (gnus-group-next-unread-group).

p
DEL
     Go to the previous group that has unread articles (gnus-group-prev-unread-group).

N
     Go to the next group (gnus-group-next-group).

P
     Go to the previous group (gnus-group-prev-group).

M-n
     Go to the next unread group on the same (or lower) level (gnus-group-next-unread-group-same-level).

M-p
     Go to the previous unread group on the same (or lower) level (gnus-group-prev-unread-group-same-level).

Three commands for jumping to groups:

j
     Jump to a group (and make it visible if it isn't already) (gnus-group-jump-to-group).  Killed groups can be jumped to, just like living groups.

,
     Jump to the unread group with the lowest level (gnus-group-best-unread-group).

.
     Jump to the first group with unread articles (gnus-group-first-unread-group).

If gnus-group-goto-unread is nil, all the movement commands will move to the next group, not the next unread group.  Even the commands that say they move to the next unread group.  The default is t.

If gnus-summary-next-group-on-exit is t, when a summary is exited, the point in the group buffer is moved to the next unread group. Otherwise, the point is set to the group just exited.  The default is t.

Selecting a Group
=================

SPACE
     Select the current group, switch to the summary buffer and display the first unread article (gnus-group-read-group).  If there are no unread articles in the group, or if you give a non-numerical prefix to this command, Gnus will offer to fetch all the old articles in this group from the server.  If you give a numerical prefix N, N determines the number of articles Gnus will fetch.  If N is positive, Gnus fetches the N newest articles, if N is negative, Gnus fetches the abs(N) oldest articles.

     Thus, SPC enters the group normally, C-u SPC offers old articles, C-u 4 2 SPC fetches the 42 newest articles, and C-u - 4 2 SPC fetches the 42 oldest ones.

     When you are in the group (in the Summary buffer), you can type M-g to fetch new articles, or C-u M-g to also show the old ones.

RET
     Select the current group and switch to the summary buffer (gnus-group-select-group).  Takes the same arguments as gnus-group-read-group---the only difference is that this command does not display the first unread article automatically upon group entry.

M-RET
     This does the same as the command above, but tries to do it with the minimum amount of fuzz (gnus-group-quick-select-group).  No scoring/killing will be performed, there will be no highlights and no expunging.  This might be useful if you're in a real hurry and have to enter some humongous group.  If you give a 0 prefix to this command (i.e., 0 M-RET), Gnus won't even generate the summary buffer, which is useful if you want to toggle threading before generating the summary buffer (see Summary Generation Commands).

M-SPACE
     This is yet one more command that does the same as the RET command, but this one does it without expunging and hiding dormants (gnus-group-visible-select-group).

C-M-RET
     Finally, this command selects the current group ephemerally without doing any processing of its contents (gnus-group-select-group-ephemerally).  Even threading has been turned off.  Everything you do in the group after selecting it in this manner will have no permanent effects.

The gnus-large-newsgroup variable says what Gnus should consider to be a big group.  If it is nil, no groups are considered big.  The default value is 200.  If the group has more (unread and/or ticked) articles than this, Gnus will query the user before entering the group.  The user can then specify how many articles should be fetched from the server.  If the user specifies a negative number (-N), the N oldest articles will be fetched.  If it is positive, the N articles that have arrived most recently will be fetched.

gnus-large-ephemeral-newsgroup is the same as gnus-large-newsgroup, but is only used for ephemeral newsgroups.

In groups in some news servers, there might be a big gap between a few very old articles that will never be expired and the recent ones.  In such a case, the server will return the data like (1 . 30000000) for the LIST ACTIVE group command, for example.  Even if there are actually only the articles 1-10 and 29999900-30000000, Gnus doesn't know it at first and prepares for getting 30000000 articles.  However, it will consume hundreds megabytes of memories and might make Emacs get stuck as the case may be.  If you use such news servers, set the variable gnus-newsgroup-maximum-articles to a positive number. The value means that Gnus ignores articles other than this number of the latest ones in every group.  For instance, the value 10000 makes Gnus get only the articles 29990001-30000000 (if the latest article number is 30000000 in a group).  Note that setting this variable to a number might prevent you from reading very old articles.  The default value of the variable gnus-newsgroup-maximum-articles is nil, which means Gnus never ignores old articles.

If gnus-auto-select-first is non-nil, select an article automatically when entering a group with the SPACE command. Which article this is controlled by the gnus-auto-select-subject variable.  Valid values for this variable are:

unread
     Place point on the subject line of the first unread article.

first
     Place point on the subject line of the first article.

unseen
     Place point on the subject line of the first unseen article.

unseen-or-unread
     Place point on the subject line of the first unseen article, and if there is no such article, place point on the subject line of the first unread article.

best
     Place point on the subject line of the highest-scored unread article.

This variable can also be a function.  In that case, that function will be called to place point on a subject line.

If you want to prevent automatic selection in some group (say, in a binary group with Huge articles) you can set the gnus-auto-select-first variable to nil in gnus-select-group-hook, which is called when a group is selected.

Subscription Commands
=====================

The following commands allow for managing your subscriptions in the Group buffer.  If you want to subscribe to many groups, it's probably more convenient to go to the Server Buffer, and choose the server there using RET or SPC.  Then you'll have the commands listed in Browse Foreign Server at hand.

S t
u
     Toggle subscription to the current group (gnus-group-unsubscribe-current-group).

S s
U
     Prompt for a group to subscribe, and then subscribe it.  If it was subscribed already, unsubscribe it instead (gnus-group-unsubscribe-group).

S k
C-k
     Kill the current group (gnus-group-kill-group).

S y
C-y
     Yank the last killed group (gnus-group-yank-group).

C-x C-t
     Transpose two groups (gnus-group-transpose-groups).  This isn't really a subscription command, but you can use it instead of a kill-and-yank sequence sometimes.

S w
C-w
     Kill all groups in the region (gnus-group-kill-region).

S z
     Kill all zombie groups (gnus-group-kill-all-zombies).

S C-k
     Kill all groups on a certain level (gnus-group-kill-level). These groups can't be yanked back after killing, so this command should be used with some caution.  The only time where this command comes in really handy is when you have a .newsrc with lots of unsubscribed groups that you want to get rid off.  S C-k on level 7 will kill off all unsubscribed groups that do not have message numbers in the .newsrc file.

Also see Group Levels.

Group Data
==========

c
     Mark all unticked articles in this group as read (gnus-group-catchup-current). gnus-group-catchup-group-hook is called when catching up a group from the group buffer.

C
     Mark all articles in this group, even the ticked ones, as read (gnus-group-catchup-current-all).

M-c
     Clear the data from the current group---nix out marks and the list of read articles (gnus-group-clear-data).

M-x gnus-group-clear-data-on-native-groups
     If you have switched from one NNTP server to another, all your marks and read ranges have become worthless.  You can use this command to clear out all data that you have on your native groups.  Use with caution.

Group Levels
============

All groups have a level of subscribedness.  For instance, if a group is on level 2, it is more subscribed than a group on level 5.  You can ask Gnus to just list groups on a given level or lower (see Listing Groups), or to just check for new articles in groups on a given level or lower (see Scanning New Messages).

Remember:  The higher the level of the group, the less important it is.

S l
     Set the level of the current group.  If a numeric prefix is given, the next N groups will have their levels set.  The user will be prompted for a level.

Gnus considers groups from levels 1 to gnus-level-subscribed (inclusive) (default 5) to be subscribed, gnus-level-subscribed (exclusive) and gnus-level-unsubscribed (inclusive) (default 7) to be unsubscribed, gnus-level-zombie to be zombies (walking dead) (default 8) and gnus-level-killed to be killed (completely dead) (default 9).  Gnus treats subscribed and unsubscribed groups exactly the same, but zombie and killed groups have no information on what articles you have read, etc, stored.  This distinction between dead and living groups isn't done because it is nice or clever, it is done purely for reasons of efficiency.

It is recommended that you keep all your mail groups (if any) on quite low levels (e.g. 1 or 2).

Maybe the following description of the default behavior of Gnus helps to understand what these levels are all about.  By default, Gnus shows you subscribed nonempty groups, but by hitting L you can have it show empty subscribed groups and unsubscribed groups, too.  Type l to go back to showing nonempty subscribed groups again.  Thus, unsubscribed groups are hidden, in a way.

Zombie and killed groups are similar to unsubscribed groups in that they are hidden by default.  But they are different from subscribed and unsubscribed groups in that Gnus doesn't ask the news server for information (number of messages, number of unread messages) on zombie and killed groups.  Normally, you use C-k to kill the groups you aren't interested in.  If most groups are killed, Gnus is faster.

Why does Gnus distinguish between zombie and killed groups?  Well, when a new group arrives on the server, Gnus by default makes it a zombie group.  This means that you are normally not bothered with new groups, but you can type A z to get a list of all new groups.  Subscribe the ones you like and kill the ones you don't want.  (A k shows a list of killed groups.)

If you want to play with the level variables, you should show some care. Set them once, and don't touch them ever again.  Better yet, don't touch them at all unless you know exactly what you're doing.

Two closely related variables are gnus-level-default-subscribed (default 3) and gnus-level-default-unsubscribed (default 6), which are the levels that new groups will be put on if they are (un)subscribed.  These two variables should, of course, be inside the relevant valid ranges.

If gnus-keep-same-level is non-nil, some movement commands will only move to groups of the same level (or lower).  In particular, going from the last article in one group to the next group will go to the next group of the same level (or lower).  This might be handy if you want to read the most important groups before you read the rest.

If this variable is best, Gnus will make the next newsgroup the one with the best level.

All groups with a level less than or equal to gnus-group-default-list-level will be listed in the group buffer by default. This variable can also be a function.  In that case, that function will be called and the result will be used as value.

If gnus-group-list-inactive-groups is non-nil, non-active groups will be listed along with the unread groups.  This variable is t by default.  If it is nil, inactive groups won't be listed.

If gnus-group-use-permanent-levels is non-nil, once you give a level prefix to g or l, all subsequent commands will use this level as the ``work'' level.

Gnus will normally just activate (i. e., query the server about) groups on level gnus-activate-level or less.  If you don't want to activate unsubscribed groups, for instance, you might set this variable to 5.  The default is 6.

Group Score
===========

You would normally keep important groups on high levels, but that scheme is somewhat restrictive.  Don't you wish you could have Gnus sort the group buffer according to how often you read groups, perhaps?  Within reason?

This is what group score is for.  You can have Gnus assign a score to each group through the mechanism described below.  You can then sort the group buffer based on this score.  Alternatively, you can sort on score and then level.  (Taken together, the level and the score is called the rank of the group.  A group that is on level 4 and has a score of 1 has a higher rank than a group on level 5 that has a score of 300.  (The level is the most significant part and the score is the least significant part.))

If you want groups you read often to get higher scores than groups you read seldom you can add the gnus-summary-bubble-group function to the gnus-summary-exit-hook hook.  This will result (after sorting) in a bubbling sort of action.  If you want to see that in action after each summary exit, you can add gnus-group-sort-groups-by-rank or gnus-group-sort-groups-by-score to the same hook, but that will slow things down somewhat.

Marking Groups
==============

If you want to perform some command on several groups, and they appear subsequently in the group buffer, you would normally just give a numerical prefix to the command.  Most group commands will then do your bidding on those groups.

However, if the groups are not in sequential order, you can still perform a command on several groups.  You simply mark the groups first with the process mark and then execute the command.

#
M m
     Set the mark on the current group (gnus-group-mark-group).

M-#
M u
     Remove the mark from the current group (gnus-group-unmark-group).

M U
     Remove the mark from all groups (gnus-group-unmark-all-groups).

M w
     Mark all groups between point and mark (gnus-group-mark-region).

M b
     Mark all groups in the buffer (gnus-group-mark-buffer).

M r
     Mark all groups that match some regular expression (gnus-group-mark-regexp).

Also see Process/Prefix.

If you want to execute some command on all groups that have been marked with the process mark, you can use the M-& (gnus-group-universal-argument) command.  It will prompt you for the command to be executed.

Foreign Groups
==============

Below are some group mode commands for making and editing general foreign groups, as well as commands to ease the creation of a few special-purpose groups.  All these commands insert the newly created groups under point---gnus-subscribe-newsgroup-method is not consulted.

Changes from the group editing commands are stored in ~/.newsrc.eld (gnus-startup-file).  An alternative is the variable gnus-parameters, see Group Parameters.

G m
     Make a new group (gnus-group-make-group).  Gnus will prompt you for a name, a method and possibly an address.  For an easier way to subscribe to NNTP groups (see Browse Foreign Server).

G M
     Make an ephemeral group (gnus-group-read-ephemeral-group).  Gnus will prompt you for a name, a method and an address.

G r
     Rename the current group to something else (gnus-group-rename-group).  This is valid only on some groups---mail groups mostly.  This command might very well be quite slow on some back ends.

G c
     Customize the group parameters (gnus-group-customize).

G e
     Enter a buffer where you can edit the select method of the current group (gnus-group-edit-group-method).

G p
     Enter a buffer where you can edit the group parameters (gnus-group-edit-group-parameters).

G E
     Enter a buffer where you can edit the group info (gnus-group-edit-group).

G d
     Make a directory group (see Directory Groups).  You will be prompted for a directory name (gnus-group-make-directory-group).

G h
     Make the Gnus help group (gnus-group-make-help-group).

G D
     Read an arbitrary directory as if it were a newsgroup with the nneething back end (gnus-group-enter-directory). See Anything Groups.

G f
     Make a group based on some file or other (gnus-group-make-doc-group).  If you give a prefix to this command, you will be prompted for a file name and a file type. Currently supported types are mbox, babyl, digest, news, rnews, mmdf, forward, rfc934, rfc822-forward, mime-parts, standard-digest, slack-digest, clari-briefs, nsmail, outlook, oe-dbx, and mailman.  If you run this command without a prefix, Gnus will guess at the file type.  See Document Groups.

G u
     Create one of the groups mentioned in gnus-useful-groups (gnus-group-make-useful-group).

G w
     Make an ephemeral group based on a web search (gnus-group-make-web-group).  If you give a prefix to this command, make a solid group instead.  You will be prompted for the search engine type and the search string.  Valid search engine types include google, dejanews, and gmane. See Web Searches.

     If you use the google search engine, you can limit the search to a particular group by using a match string like shaving group:alt.sysadmin.recovery.

G R
     Make a group based on an RSS feed (gnus-group-make-rss-group).  You will be prompted for an URL. See RSS.

G DEL
     This function will delete the current group (gnus-group-delete-group).  If given a prefix, this function will actually delete all the articles in the group, and forcibly remove the group itself from the face of the Earth.  Use a prefix only if you are absolutely sure of what you are doing.  This command can't be used on read-only groups (like nntp groups), though.

G V
     Make a new, fresh, empty nnvirtual group (gnus-group-make-empty-virtual).  See Virtual Groups.

G v
     Add the current group to an nnvirtual group (gnus-group-add-to-virtual).  Uses the process/prefix convention.

See Select Methods, for more information on the various select methods.

If gnus-activate-foreign-newsgroups is a positive number, Gnus will check all foreign groups with this level or lower at startup. This might take quite a while, especially if you subscribe to lots of groups from different NNTP servers.  Also see Group Levels; gnus-activate-level also affects activation of foreign newsgroups.

The following commands create ephemeral groups.  They can be called not only from the Group buffer, but in any Gnus buffer.

gnus-read-ephemeral-gmane-group
     Read an ephemeral group on Gmane.org.  The articles are downloaded via HTTP using the URL specified by gnus-gmane-group-download-format. Gnus will prompt you for a group name, the start article number and an the article range.

gnus-read-ephemeral-gmane-group-url
     This command is similar to gnus-read-ephemeral-gmane-group, but the group name and the article number and range are constructed from a given URL.  Supported URL formats include e.g. http://thread.gmane.org/gmane.foo.bar/12300/focus=12399, http://thread.gmane.org/gmane.foo.bar/12345/, http://article.gmane.org/gmane.foo.bar/12345/, http://permalink.gmane.org/gmane.foo.bar/12345/, and http://news.gmane.org/group/gmane.foo.bar/thread=12345.

gnus-read-ephemeral-emacs-bug-group
     Read an Emacs bug report in an ephemeral group.  Gnus will prompt for a bug number.  The default is the number at point.  The URL is specified in gnus-bug-group-download-format-alist.

gnus-read-ephemeral-debian-bug-group
     Read a Debian bug report in an ephemeral group.  Analog to gnus-read-ephemeral-emacs-bug-group.

Some of these command are also useful for article buttons, see Article Buttons.

Here is an example:

     (require 'gnus-art)
     (add-to-list
      'gnus-button-alist
      '("#\\([0-9]+\\)\\>" 1
        (string-match "\\<emacs\\>" (or gnus-newsgroup-name ""))
        gnus-read-ephemeral-emacs-bug-group 1))

Group Parameters
================

The group parameters store information local to a particular group.

Use the G p or the G c command to edit group parameters of a group.  (G p presents you with a Lisp-based interface, G c presents you with a Customize-like interface.  The latter helps avoid silly Lisp errors.)  You might also be interested in reading about topic parameters (see Topic Parameters). Additionally, you can set group parameters via the gnus-parameters variable, see below.

Here's an example group parameter list:

     ((to-address . "ding@gnus.org")
      (auto-expire . t))

We see that each element consists of a ``dotted pair''---the thing before the dot is the key, while the thing after the dot is the value.  All the parameters have this form except local variable specs, which are not dotted pairs, but proper lists.

Some parameters have correspondent customizable variables, each of which is an alist of regexps and values.

The following group parameters can be used:

to-address
     Address used by when doing followups and new posts.

          (to-address . "some@where.com")

     This is primarily useful in mail groups that represent closed mailing lists---mailing lists where it's expected that everybody that writes to the mailing list is subscribed to it.  Since using this parameter ensures that the mail only goes to the mailing list itself, it means that members won't receive two copies of your followups.

     Using to-address will actually work whether the group is foreign or not.  Let's say there's a group on the server that is called fa.4ad-l.  This is a real newsgroup, but the server has gotten the articles from a mail-to-news gateway.  Posting directly to this group is therefore impossible---you have to send mail to the mailing list address instead.

     See also gnus-parameter-to-address-alist.

to-list
     Address used when doing a in that group.

          (to-list . "some@where.com")

     It is totally ignored when doing a followup---except that if it is present in a news group, you'll get mail group semantics when doing f.

     If you do an a command in a mail group and you have neither a to-list group parameter nor a to-address group parameter, then a to-list group parameter will be added automatically upon sending the message if gnus-add-to-list is set to t.

     If this variable is set, gnus-mailing-list-mode is turned on when entering summary buffer.

     See also gnus-parameter-to-list-alist.

subscribed
     If this parameter is set to t, Gnus will consider the to-address and to-list parameters for this group as addresses of mailing lists you are subscribed to.  Giving Gnus this information is (only) a first step in getting it to generate correct Mail-Followup-To headers for your posts to these lists.  The second step is to put the following in your .gnus.el

          (setq message-subscribed-address-functions
                '(gnus-find-subscribed-addresses))

     See Mailing Lists (The Message Manual), for a complete treatment of available MFT support.

visible
     If the group parameter list has the element (visible . t), that group will always be visible in the Group buffer, regardless of whether it has any unread articles.

     This parameter cannot be set via gnus-parameters. See gnus-permanently-visible-groups as an alternative.

broken-reply-to
     Elements like (broken-reply-to . t) signals that Reply-To headers in this group are to be ignored, and for the header to be hidden if reply-to is part of gnus-boring-article-headers.  This can be useful if you're reading a mailing list group where the listserv has inserted Reply-To headers that point back to the listserv itself.  That is broken behavior.  So there!

to-group
     Elements like (to-group . "some.group.name") means that all posts in that group will be sent to some.group.name.

newsgroup
     If you have (newsgroup . t) in the group parameter list, Gnus will treat all responses as if they were responses to news articles. This can be useful if you have a mail group that's really a mirror of a news group.

gcc-self
     If (gcc-self . t) is present in the group parameter list, newly composed messages will be Gcc'd to the current group.  If (gcc-self . none) is present, no Gcc: header will be generated, if (gcc-self . "string") is present, this string will be inserted literally as a gcc header.  This parameter takes precedence over any default Gcc rules as described later (see Archived Messages).

     Caveat: Adding (gcc-self . t) to the parameter list of nntp groups (or the like) isn't valid.  An nntp server doesn't accept articles.

auto-expire
     If the group parameter has an element that looks like (auto-expire . t), all articles read will be marked as expirable.  For an alternative approach, see Expiring Mail.

     See also gnus-auto-expirable-newsgroups.

total-expire
     If the group parameter has an element that looks like (total-expire . t), all read articles will be put through the expiry process, even if they are not marked as expirable.  Use with caution.  Unread, ticked and dormant articles are not eligible for expiry.

     See also gnus-total-expirable-newsgroups.

expiry-wait
     If the group parameter has an element that looks like (expiry-wait . 10), this value will override any nnmail-expiry-wait and nnmail-expiry-wait-function (see Expiring Mail) when expiring expirable messages.  The value can either be a number of days (not necessarily an integer) or the symbols never or immediate.

expiry-target
     Where expired messages end up.  This parameter overrides nnmail-expiry-target.

score-file
     Elements that look like (score-file . "file") will make file into the current score file for the group in question.  All interactive score entries will be put into this file.

adapt-file
     Elements that look like (adapt-file . "file") will make file into the current adaptive file for the group in question. All adaptive score entries will be put into this file.

admin-address
     When unsubscribing from a mailing list you should never send the unsubscription notice to the mailing list itself.  Instead, you'd send messages to the administrative address.  This parameter allows you to put the admin address somewhere convenient.

display
     Elements that look like (display . MODE) say which articles to display on entering the group.  Valid values are:

     all
          Display all articles, both read and unread.

     an integer
          Display the last INTEGER articles in the group.  This is the same as entering the group with C-u INTEGER.

     default
          Display the default visible articles, which normally includes unread and ticked articles.

     an array
          Display articles that satisfy a predicate.

          Here are some examples:

          [unread]
               Display only unread articles.

          [not expire]
               Display everything except expirable articles.

          [and (not reply) (not expire)]
               Display everything except expirable and articles you've already responded to.

          The available operators are not, and and or. Predicates include tick, unsend, undownload, unread, dormant, expire, reply, killed, bookmark, score, save, cache, forward, unseen and recent.

     The display parameter works by limiting the summary buffer to the subset specified.  You can pop the limit by using the / w command (see Limiting).

comment
     Elements that look like (comment . "This is a comment") are arbitrary comments on the group.  You can display comments in the group line (see Group Line Specification).

charset
     Elements that look like (charset . iso-8859-1) will make iso-8859-1 the default charset; that is, the charset that will be used for all articles that do not specify a charset.

     See also gnus-group-charset-alist.

ignored-charsets
     Elements that look like (ignored-charsets x-unknown iso-8859-1) will make iso-8859-1 and x-unknown ignored; that is, the default charset will be used for decoding articles.

     See also gnus-group-ignored-charsets-alist.

posting-style
     You can store additional posting style information for this group here (see Posting Styles).  The format is that of an entry in the gnus-posting-styles alist, except that there's no regexp matching the group name (of course).  Style elements in this group parameter will take precedence over the ones found in gnus-posting-styles.

     For instance, if you want a funky name and signature in this group only, instead of hacking gnus-posting-styles, you could put something like this in the group parameters:

          (posting-style
            (name "Funky Name")
            ("X-My-Header" "Funky Value")
            (signature "Funky Signature"))

     If you're using topics to organize your group buffer (see Group Topics), note that posting styles can also be set in the topics parameters. Posting styles in topic parameters apply to all groups in this topic. More precisely, the posting-style settings for a group result from the hierarchical merging of all posting-style entries in the parameters of this group and all the topics it belongs to.

post-method
     If it is set, the value is used as the method for posting message instead of gnus-post-method.

mail-source
     If it is set, and the setting of mail-sources includes a group mail source (see Mail Sources), the value is a mail source for this group.

banner
     An item like (banner . REGEXP) causes any part of an article that matches the regular expression REGEXP to be stripped.  Instead of REGEXP, you can also use the symbol signature which strips the last signature or any of the elements of the alist gnus-article-banner-alist.

sieve
     This parameter contains a Sieve test that should match incoming mail that should be placed in this group.  From this group parameter, a Sieve IF control structure is generated, having the test as the condition and fileinto "group.name"; as the body.

     For example, if the INBOX.list.sieve group has the (sieve address "sender" "sieve-admin@extundo.com") group parameter, when translating the group parameter into a Sieve script (see Sieve Commands) the following Sieve code is generated:

          if address "sender" "sieve-admin@extundo.com" {
                  fileinto "INBOX.list.sieve";
          }

     To generate tests for multiple email-addresses use a group parameter like (sieve address "sender" ("name@one.org" else@two.org")). When generating a sieve script (see Sieve Commands) Sieve code like the following is generated:

          if address "sender" ["name@one.org", "else@two.org"] {
                  fileinto "INBOX.list.sieve";
          }

     See Sieve Commands for commands and variables that might be of interest in relation to the sieve parameter.

     The Sieve language is described in RFC 3028.  See Emacs Sieve.

(agent parameters)
     If the agent has been enabled, you can set any of its parameters to control the behavior of the agent in individual groups.  See Agent Parameters in Category Syntax.  Most users will choose to set agent parameters in either an agent category or group topic to minimize the configuration effort.

(VARIABLE FORM)
     You can use the group parameters to set variables local to the group you are entering.  If you want to turn threading off in news.answers, you could put (gnus-show-threads nil) in the group parameters of that group.  gnus-show-threads will be made into a local variable in the summary buffer you enter, and the form nil will be evaled there.

     Note that this feature sets the variable locally to the summary buffer if and only if VARIABLE has been bound as a variable.  Otherwise, only evaluating the form will take place.  So, you may want to bind the variable in advance using defvar or other if the result of the form needs to be set to it.

     But some variables are evaluated in the article buffer, or in the message buffer (of a reply or followup or otherwise newly created message).  As a workaround, it might help to add the variable in question to gnus-newsgroup-variables.  See Various Summary Stuff.  So if you want to set message-from-style via the group parameters, then you may need the following statement elsewhere in your ~/.gnus.el file:

          (add-to-list 'gnus-newsgroup-variables 'message-from-style)

     A use for this feature is to remove a mailing list identifier tag in the subject fields of articles.  E.g. if the news group

          nntp+news.gnus.org:gmane.text.docbook.apps

     has the tag DOC-BOOK-APPS: in the subject of all articles, this tag can be removed from the article subjects in the summary buffer for the group by putting (gnus-list-identifiers "DOCBOOK-APPS:") into the group parameters for the group.

     This can also be used as a group-specific hook function.  If you want to hear a beep when you enter a group, you could put something like (dummy-variable (ding)) in the parameters of that group.  If dummy-variable has been bound (see above), it will be set to the (meaningless) result of the (ding) form.

     Alternatively, since the VARIABLE becomes local to the group, this pattern can be used to temporarily change a hook.  For example, if the following is added to a group parameter

          (gnus-summary-prepared-hook
            '(lambda nil (local-set-key "d" (local-key-binding "n"))))

     when the group is entered, the 'd' key will not mark the article as expired.

Group parameters can be set via the gnus-parameters variable too. But some variables, such as visible, have no effect (For this case see gnus-permanently-visible-groups as an alternative.). For example:

     (setq gnus-parameters
           '(("mail\\..*"
              (gnus-show-threads nil)
              (gnus-use-scoring nil)
              (gnus-summary-line-format
               "%U%R%z%I%(%[%d:%ub%-23,23f%]%) %s\n")
              (gcc-self . t)
              (display . all))

             ("^nnimap:\\(foo.bar\\)$"
              (to-group . "\\1"))

             ("mail\\.me"
              (gnus-use-scoring  t))

             ("list\\..*"
              (total-expire . t)
              (broken-reply-to . t))))

String value of parameters will be subjected to regexp substitution, as the to-group example shows.

By default, whether comparing the group name and one of those regexps specified in gnus-parameters is done in a case-sensitive manner or a case-insensitive manner depends on the value of case-fold-search at the time when the comparison is done.  The value of case-fold-search is typically t; it means, for example, the element ("INBOX\\.FOO" (total-expire . t)) might be applied to both the INBOX.FOO group and the INBOX.foo group.  If you want to make those regexps always case-sensitive, set the value of the gnus-parameters-case-fold-search variable to nil.  Otherwise, set it to t if you want to compare them always in a case-insensitive manner.

You can define different sorting to different groups via gnus-parameters.  Here is an example to sort an NNTP group by reverse date to see the latest news at the top and an RSS group by subject.  In this example, the first group is the Debian daily news group gmane.linux.debian.user.news from news.gmane.org.  The RSS group corresponds to the Debian weekly news RSS feed http://packages.debian.org/unstable/newpkg_main.en.rdf, see RSS.

     (setq
      gnus-parameters
      '(("nntp.*gmane\\.debian\\.user\\.news"
         (gnus-show-threads nil)
         (gnus-article-sort-functions '((not gnus-article-sort-by-date)))
         (gnus-use-adaptive-scoring nil)
         (gnus-use-scoring nil))
        ("nnrss.*debian"
         (gnus-show-threads nil)
         (gnus-article-sort-functions 'gnus-article-sort-by-subject)
         (gnus-use-adaptive-scoring nil)
         (gnus-use-scoring t)
         (gnus-score-find-score-files-function 'gnus-score-find-single)
         (gnus-summary-line-format "%U%R%z%d %I%(%[ %s %]%)\n"))))

Listing Groups
==============

These commands all list various slices of the groups available.

l
A s
     List all groups that have unread articles (gnus-group-list-groups).  If the numeric prefix is used, this command will list only groups of level ARG and lower.  By default, it only lists groups of level five (i.e., gnus-group-default-list-level) or lower (i.e., just subscribed groups).

L
A u
     List all groups, whether they have unread articles or not (gnus-group-list-all-groups).  If the numeric prefix is used, this command will list only groups of level ARG and lower.  By default, it lists groups of level seven or lower (i.e., just subscribed and unsubscribed groups).

A l
     List all unread groups on a specific level (gnus-group-list-level).  If given a prefix, also list the groups with no unread articles.

A k
     List all killed groups (gnus-group-list-killed).  If given a prefix argument, really list all groups that are available, but aren't currently (un)subscribed.  This could entail reading the active file from the server.

A z
     List all zombie groups (gnus-group-list-zombies).

A m
     List all unread, subscribed groups with names that match a regexp (gnus-group-list-matching).

A M
     List groups that match a regexp (gnus-group-list-all-matching).

A A
     List absolutely all groups in the active file(s) of the server(s) you are connected to (gnus-group-list-active).  This might very well take quite a while.  It might actually be a better idea to do a A M to list all matching, and just give . as the thing to match on.  Also note that this command may list groups that don't exist (yet)---these will be listed as if they were killed groups. Take the output with some grains of salt.

A a
     List all groups that have names that match a regexp (gnus-group-apropos).

A d
     List all groups that have names or descriptions that match a regexp (gnus-group-description-apropos).

A c
     List all groups with cached articles (gnus-group-list-cached).

A ?
     List all groups with dormant articles (gnus-group-list-dormant).

A /
     List groups limited within the current selection (gnus-group-list-limit).

A f
     Flush groups from the current selection (gnus-group-list-flush).

A p
     List groups plus the current selection (gnus-group-list-plus).

Groups that match the gnus-permanently-visible-groups regexp will always be shown, whether they have unread articles or not.  You can also add the visible element to the group parameters in question to get the same effect.

Groups that have just ticked articles in it are normally listed in the group buffer.  If gnus-list-groups-with-ticked-articles is nil, these groups will be treated just like totally empty groups.  It is t by default.

Sorting Groups
==============

The C-c C-s (gnus-group-sort-groups) command sorts the group buffer according to the function(s) given by the gnus-group-sort-function variable.  Available sorting functions include:

gnus-group-sort-by-alphabet
     Sort the group names alphabetically.  This is the default.

gnus-group-sort-by-real-name
     Sort the group alphabetically on the real (unprefixed) group names.

gnus-group-sort-by-level
     Sort by group level.

gnus-group-sort-by-score
     Sort by group score.  See Group Score.

gnus-group-sort-by-rank
     Sort by group score and then the group level.  The level and the score are, when taken together, the group's rank.  See Group Score.

gnus-group-sort-by-unread
     Sort by number of unread articles.

gnus-group-sort-by-method
     Sort alphabetically on the select method.

gnus-group-sort-by-server
     Sort alphabetically on the Gnus server name.

gnus-group-sort-function can also be a list of sorting functions.  In that case, the most significant sort key function must be the last one.

There are also a number of commands for sorting directly according to some sorting criteria:

G S a
     Sort the group buffer alphabetically by group name (gnus-group-sort-groups-by-alphabet).

G S u
     Sort the group buffer by the number of unread articles (gnus-group-sort-groups-by-unread).

G S l
     Sort the group buffer by group level (gnus-group-sort-groups-by-level).

G S v
     Sort the group buffer by group score (gnus-group-sort-groups-by-score).  See Group Score.

G S r
     Sort the group buffer by group rank (gnus-group-sort-groups-by-rank).  See Group Score.

G S m
     Sort the group buffer alphabetically by back end name

     (gnus-group-sort-groups-by-method).

G S n
     Sort the group buffer alphabetically by real (unprefixed) group name (gnus-group-sort-groups-by-real-name).

All the commands below obey the process/prefix convention (see Process/Prefix).

When given a symbolic prefix (see Symbolic Prefixes), all these commands will sort in reverse order.

You can also sort a subset of the groups:

G P a
     Sort the groups alphabetically by group name (gnus-group-sort-selected-groups-by-alphabet).

G P u
     Sort the groups by the number of unread articles (gnus-group-sort-selected-groups-by-unread).

G P l
     Sort the groups by group level (gnus-group-sort-selected-groups-by-level).

G P v
     Sort the groups by group score (gnus-group-sort-selected-groups-by-score).  See Group Score.

G P r
     Sort the groups by group rank (gnus-group-sort-selected-groups-by-rank).  See Group Score.

G P m
     Sort the groups alphabetically by back end name

     (gnus-group-sort-selected-groups-by-method).

G P n
     Sort the groups alphabetically by real (unprefixed) group name (gnus-group-sort-selected-groups-by-real-name).

G P s
     Sort the groups according to gnus-group-sort-function.

And finally, note that you can use C-k and C-y to manually move groups around.

Group Maintenance
=================

b
     Find bogus groups and delete them (gnus-group-check-bogus-groups).

F
     Find new groups and process them (gnus-group-find-new-groups). With 1 C-u, use the ask-server method to query the server for new groups.  With 2 C-u's, use most complete method possible to query the server for new groups, and subscribe the new groups as zombies.

C-c C-x
     Run all expirable articles in the current group through the expiry process (if any) (gnus-group-expire-articles).  That is, delete all expirable articles in the group that have been around for a while. (see Expiring Mail).

C-c C-M-x
     Run all expirable articles in all groups through the expiry process (gnus-group-expire-all-groups).

Browse Foreign Server
=====================

B
     You will be queried for a select method and a server name.  Gnus will then attempt to contact this server and let you browse the groups there (gnus-group-browse-foreign-server).

A new buffer with a list of available groups will appear.  This buffer will use the gnus-browse-mode.  This buffer looks a bit (well, a lot) like a normal group buffer.

Here's a list of keystrokes available in the browse mode:

n
     Go to the next group (gnus-group-next-group).

p
     Go to the previous group (gnus-group-prev-group).

SPACE
     Enter the current group and display the first article (gnus-browse-read-group).

RET
     Enter the current group (gnus-browse-select-group).

u
     Unsubscribe to the current group, or, as will be the case here, subscribe to it (gnus-browse-unsubscribe-current-group).  You can affect the way the new group is entered into the Group buffer using the variable gnus-browse-subscribe-newsgroup-method.  See Subscription Methods for available options.

l
q
     Exit browse mode (gnus-browse-exit).

d
     Describe the current group (gnus-browse-describe-group).

?
     Describe browse mode briefly (well, there's not much to describe, is there) (gnus-browse-describe-briefly).

Exiting Gnus
============

Yes, Gnus is ex(c)iting.

z
     Suspend Gnus (gnus-group-suspend).  This doesn't really exit Gnus, but it kills all buffers except the Group buffer.  I'm not sure why this is a gain, but then who am I to judge?

q
     Quit Gnus (gnus-group-exit).

Q
     Quit Gnus without saving the .newsrc files (gnus-group-quit). The dribble file will be saved, though (see Auto Save).

gnus-suspend-gnus-hook is called when you suspend Gnus and gnus-exit-gnus-hook is called when you quit Gnus, while gnus-after-exiting-gnus-hook is called as the final item when exiting Gnus.

Note:

     Miss Lisa Cannifax, while sitting in English class, felt her feet go numbly heavy and herself fall into a hazy trance as the boy sitting behind her drew repeated lines with his pencil across the back of her plastic chair.

Group Topics
============

If you read lots and lots of groups, it might be convenient to group them hierarchically according to topics.  You put your Emacs groups over here, your sex groups over there, and the rest (what, two groups or so?) you put in some misc section that you never bother with anyway.  You can even group the Emacs sex groups as a sub-topic to either the Emacs groups or the sex groups---or both!  Go wild!

Here's an example:

     Gnus
       Emacs -- I wuw it!
          3: comp.emacs
          2: alt.religion.emacs
         Naughty Emacs
          452: alt.sex.emacs
            0: comp.talk.emacs.recovery
       Misc
          8: comp.binaries.fractals
         13: comp.sources.unix

To get this fab functionality you simply turn on (ooh!) the gnus-topic minor mode---type t in the group buffer.  (This is a toggling command.)

Go ahead, just try it.  I'll still be here when you get back.  La de dum... Nice tune, that... la la la... What, you're back? Yes, and now press l.  There.  All your groups are now listed under misc.  Doesn't that make you feel all warm and fuzzy? Hot and bothered?

If you want this permanently enabled, you should add that minor mode to the hook for the group mode.  Put the following line in your ~/.gnus.el file:

     (add-hook 'gnus-group-mode-hook 'gnus-topic-mode)

Topic Commands
--------------

When the topic minor mode is turned on, a new T submap will be available.  In addition, a few of the standard keys change their definitions slightly.

In general, the following kinds of operations are possible on topics. First of all, you want to create topics.  Secondly, you want to put groups in topics and to move them around until you have an order you like.  The third kind of operation is to show/hide parts of the whole shebang.  You might want to hide a topic including its subtopics and groups, to get a better overview of the other groups.

Here is a list of the basic keys that you might need to set up topics the way you like.

T n
     Prompt for a new topic name and create it (gnus-topic-create-topic).

T TAB
TAB
     ``Indent'' the current topic so that it becomes a sub-topic of the previous topic (gnus-topic-indent).  If given a prefix, ``un-indent'' the topic instead.

M-TAB
     ``Un-indent'' the current topic so that it becomes a sub-topic of the parent of its current parent (gnus-topic-unindent).

The following two keys can be used to move groups and topics around. They work like the well-known cut and paste.  C-k is like cut and C-y is like paste.  Of course, this being Emacs, we use the terms kill and yank rather than cut and paste.

C-k
     Kill a group or topic (gnus-topic-kill-group).  All groups in the topic will be removed along with the topic.

C-y
     Yank the previously killed group or topic (gnus-topic-yank-group).  Note that all topics will be yanked before all groups.

     So, to move a topic to the beginning of the list of topics, just hit C-k on it.  This is like the ``cut'' part of cut and paste.  Then, move the cursor to the beginning of the buffer (just below the ``Gnus'' topic) and hit C-y.  This is like the ``paste'' part of cut and paste.  Like I said -- E-Z.

     You can use C-k and C-y on groups as well as on topics.  So you can move topics around as well as groups.

After setting up the topics the way you like them, you might wish to hide a topic, or to show it again.  That's why we have the following key.

RET
SPACE
     Either select a group or fold a topic (gnus-topic-select-group). When you perform this command on a group, you'll enter the group, as usual.  When done on a topic line, the topic will be folded (if it was visible) or unfolded (if it was folded already).  So it's basically a toggling command on topics.  In addition, if you give a numerical prefix, group on that level (and lower) will be displayed.

Now for a list of other commands, in no particular order.

T m
     Move the current group to some other topic (gnus-topic-move-group).  This command uses the process/prefix convention (see Process/Prefix).

T j
     Go to a topic (gnus-topic-jump-to-topic).

T c
     Copy the current group to some other topic (gnus-topic-copy-group).  This command uses the process/prefix convention (see Process/Prefix).

T h
     Hide the current topic (gnus-topic-hide-topic).  If given a prefix, hide the topic permanently.

T s
     Show the current topic (gnus-topic-show-topic).  If given a prefix, show the topic permanently.

T D
     Remove a group from the current topic (gnus-topic-remove-group). This command is mainly useful if you have the same group in several topics and wish to remove it from one of the topics.  You may also remove a group from all topics, but in that case, Gnus will add it to the root topic the next time you start Gnus.  In fact, all new groups (which, naturally, don't belong to any topic) will show up in the root topic.

     This command uses the process/prefix convention (see Process/Prefix).

T M
     Move all groups that match some regular expression to a topic (gnus-topic-move-matching).

T C
     Copy all groups that match some regular expression to a topic (gnus-topic-copy-matching).

T H
     Toggle hiding empty topics (gnus-topic-toggle-display-empty-topics).

T #
     Mark all groups in the current topic with the process mark (gnus-topic-mark-topic).  This command works recursively on sub-topics unless given a prefix.

T M-#
     Remove the process mark from all groups in the current topic (gnus-topic-unmark-topic).  This command works recursively on sub-topics unless given a prefix.

C-c C-x
     Run all expirable articles in the current group or topic through the expiry process (if any) (gnus-topic-expire-articles).  (see Expiring Mail).

T r
     Rename a topic (gnus-topic-rename).

T DEL
     Delete an empty topic (gnus-topic-delete).

A T
     List all groups that Gnus knows about in a topics-ified way (gnus-topic-list-active).

T M-n
     Go to the next topic (gnus-topic-goto-next-topic).

T M-p
     Go to the previous topic (gnus-topic-goto-previous-topic).

G p
     Edit the topic parameters (gnus-topic-edit-parameters). See Topic Parameters.

Topic Variables
---------------

The previous section told you how to tell Gnus which topics to display. This section explains how to tell Gnus what to display about each topic.

The topic lines themselves are created according to the gnus-topic-line-format variable (see Formatting Variables). Valid elements are:

i
     Indentation.

n
     Topic name.

v
     Visibility.

l
     Level.

g
     Number of groups in the topic.

a
     Number of unread articles in the topic.

A
     Number of unread articles in the topic and all its subtopics.

Each sub-topic (and the groups in the sub-topics) will be indented with gnus-topic-indent-level times the topic level number of spaces. The default is 2.

gnus-topic-mode-hook is called in topic minor mode buffers.

The gnus-topic-display-empty-topics says whether to display even topics that have no unread articles in them.  The default is t.

Topic Sorting
-------------

You can sort the groups in each topic individually with the following commands:

T S a
     Sort the current topic alphabetically by group name (gnus-topic-sort-groups-by-alphabet).

T S u
     Sort the current topic by the number of unread articles (gnus-topic-sort-groups-by-unread).

T S l
     Sort the current topic by group level (gnus-topic-sort-groups-by-level).

T S v
     Sort the current topic by group score (gnus-topic-sort-groups-by-score).  See Group Score.

T S r
     Sort the current topic by group rank (gnus-topic-sort-groups-by-rank).  See Group Score.

T S m
     Sort the current topic alphabetically by back end name (gnus-topic-sort-groups-by-method).

T S e
     Sort the current topic alphabetically by server name (gnus-topic-sort-groups-by-server).

T S s
     Sort the current topic according to the function(s) given by the gnus-group-sort-function variable (gnus-topic-sort-groups).

When given a prefix argument, all these commands will sort in reverse order.  See Sorting Groups, for more information about group sorting.

Topic Topology
--------------

So, let's have a look at an example group buffer:

     Gnus
       Emacs -- I wuw it!
          3: comp.emacs
          2: alt.religion.emacs
         Naughty Emacs
          452: alt.sex.emacs
            0: comp.talk.emacs.recovery
       Misc
          8: comp.binaries.fractals
         13: comp.sources.unix

So, here we have one top-level topic (Gnus), two topics under that, and one sub-topic under one of the sub-topics.  (There is always just one (1) top-level topic).  This topology can be expressed as follows:

     (("Gnus" visible)
      (("Emacs -- I wuw it!" visible)
       (("Naughty Emacs" visible)))
      (("Misc" visible)))

This is in fact how the variable gnus-topic-topology would look for the display above.  That variable is saved in the .newsrc.eld file, and shouldn't be messed with manually---unless you really want to.  Since this variable is read from the .newsrc.eld file, setting it in any other startup files will have no effect.

This topology shows what topics are sub-topics of what topics (right), and which topics are visible.  Two settings are currently allowed---visible and invisible.

Topic Parameters
----------------

All groups in a topic will inherit group parameters from the parent (and ancestor) topic parameters.  All valid group parameters are valid topic parameters (see Group Parameters).  When the agent is enabled, all agent parameters (See Agent Parameters in Category Syntax) are also valid topic parameters.

In addition, the following parameters are only valid as topic parameters:

subscribe
     When subscribing new groups by topic (see Subscription Methods), the subscribe topic parameter says what groups go in what topic.  Its value should be a regexp to match the groups that should go in that topic.

subscribe-level
     When subscribing new groups by topic (see the subscribe parameter), the group will be subscribed with the level specified in the subscribe-level instead of gnus-level-default-subscribed.

Group parameters (of course) override topic parameters, and topic parameters in sub-topics override topic parameters in super-topics.  You know.  Normal inheritance rules.  (Rules is here a noun, not a verb, although you may feel free to disagree with me here.)

     Gnus
       Emacs
          3: comp.emacs
          2: alt.religion.emacs
        452: alt.sex.emacs
         Relief
          452: alt.sex.emacs
            0: comp.talk.emacs.recovery
       Misc
          8: comp.binaries.fractals
         13: comp.sources.unix
        452: alt.sex.emacs

The Emacs topic has the topic parameter (score-file . "emacs.SCORE"); the Relief topic has the topic parameter (score-file . "relief.SCORE"); and the Misc topic has the topic parameter (score-file . "emacs.SCORE").  In addition,

 alt.religion.emacs has the group parameter (score-file
. "religion.SCORE").

Now, when you enter alt.sex.emacs in the Relief topic, you will get the relief.SCORE home score file.  If you enter the same group in the Emacs topic, you'll get the emacs.SCORE home score file.  If you enter the group alt.religion.emacs, you'll get the religion.SCORE home score file.

This seems rather simple and self-evident, doesn't it?  Well, yes.  But there are some problems, especially with the total-expiry parameter.  Say you have a mail group in two topics; one with total-expiry and one without.  What happens when you do M-x gnus-expire-all-expirable-groups?  Gnus has no way of telling which one of these topics you mean to expire articles from, so anything may happen.  In fact, I hereby declare that it is undefined what happens.  You just have to be careful if you do stuff like that.

Accessing groups of non-English names
=====================================

There are some news servers that provide groups of which the names are expressed with their native languages in the world.  For instance, in a certain news server there are some newsgroups of which the names are spelled in Chinese, where people are talking in Chinese.  You can, of course, subscribe to such news groups using Gnus.  Currently Gnus supports non-ASCII group names not only with the nntp back end but also with the nnml back end and the nnrss back end.

Every such group name is encoded by a certain charset in the server side (in an NNTP server its administrator determines the charset, but for groups in the other back ends it is determined by you). Gnus has to display the decoded ones for you in the group buffer and the article buffer, and needs to use the encoded ones when communicating with servers.  However, Gnus doesn't know what charset is used for each non-ASCII group name.  The following two variables are just the ones for telling Gnus what charset should be used for each group:

gnus-group-name-charset-method-alist
     An alist of select methods and charsets.  The default value is nil.  The names of groups in the server specified by that select method are all supposed to use the corresponding charset.  For example:

          (setq gnus-group-name-charset-method-alist
                '(((nntp "news.com.cn") . cn-gb-2312)))

     Charsets specified for groups with this variable are preferred to the ones specified for the same groups with the gnus-group-name-charset-group-alist variable (see below).

     A select method can be very long, like:

          (nntp "gmane"
                (nntp-address "news.gmane.org")
                (nntp-end-of-line "\n")
                (nntp-open-connection-function
                 nntp-open-via-rlogin-and-telnet)
                (nntp-via-rlogin-command "ssh")
                (nntp-via-rlogin-command-switches
                 ("-C" "-t" "-e" "none"))
                (nntp-via-address ...))

     In that case, you can truncate it into (nntp "gmane") in this variable.  That is, it is enough to contain only the back end name and the server name.

gnus-group-name-charset-group-alist
     An alist of regexp of group name and the charset for group names. ((".*" . utf-8)) is the default value if UTF-8 is supported, otherwise the default is nil.  For example:

          (setq gnus-group-name-charset-group-alist
                '(("\\.com\\.cn:" . cn-gb-2312)
                  (".*" . utf-8)))

     Note that this variable is ignored if the match is made with gnus-group-name-charset-method-alist.

Those two variables are used also to determine the charset for encoding and decoding non-ASCII group names that are in the back ends other than nntp.  It means that it is you who determine it.  If you do nothing, the charset used for group names in those back ends will all be utf-8 because of the last element of gnus-group-name-charset-group-alist.

There is one more important variable for non-ASCII group names:

nnmail-pathname-coding-system
     The value of this variable should be a coding system or nil.  The default is nil in Emacs, or is the aliasee of the coding system named file-name (a certain coding system of which an alias is file-name) in XEmacs.

     The nnml back end, the nnrss back end, the NNTP marks feature (see NNTP marks), the agent, and the cache use non-ASCII group names in those files and directories.  This variable overrides the value of file-name-coding-system which specifies the coding system used when encoding and decoding those file names and directory names.

     In XEmacs (with the mule feature), file-name-coding-system is the only means to specify the coding system used to encode and decode file names.  On the other hand, Emacs uses the value of default-file-name-coding-system if file-name-coding-system is nil or it is bound to the value of nnmail-pathname-coding-system which is nil.

     Normally the value of default-file-name-coding-system in Emacs or nnmail-pathname-coding-system in XEmacs is initialized according to the locale, so you will need to do nothing if the value is suitable to encode and decode non-ASCII group names.

     The value of this variable (or default-file-name-coding-system) does not necessarily need to be the same value that is determined by gnus-group-name-charset-method-alist and gnus-group-name-charset-group-alist.

     If default-file-name-coding-system or this variable is initialized by default to iso-latin-1 for example, although you want to subscribe to the groups spelled in Chinese, that is the most typical case where you have to customize nnmail-pathname-coding-system.  The utf-8 coding system is a good candidate for it.  Otherwise, you may change the locale in your system so that default-file-name-coding-system or this variable may be initialized to an appropriate value.

Note that when you copy or move articles from a non-ASCII group to another group, the charset used to encode and decode group names should be the same in both groups.  Otherwise the Newsgroups header will be displayed incorrectly in the article buffer.

Searching
=========

FIXME: This node is a stub.

FIXME: Add a brief overview of Gnus search capabilities.  A brief comparison of nnir, nnmairix, contrib/gnus-namazu would be nice as well.

FIXME: Explain difference to Searching for Articles, add reference and back-reference.

nnir
----

FIXME: As a first step, convert the commentary of nnir to texi.

nnmairix
--------

This paragraph describes how to set up mairix and the back end nnmairix for indexing and searching your mail from within Gnus.  Additionally, you can create permanent ``smart'' groups which are bound to mairix searches and are automatically updated.

About mairix
............

Mairix is a tool for indexing and searching words in locally stored mail.  It was written by Richard Curnow and is licensed under the GPL.  Mairix comes with most popular GNU/Linux distributions, but it also runs under Windows (with cygwin), Mac OS X and Solaris.  The homepage can be found at http://www.rpcurnow.force9.co.uk/mairix/index.html

Though mairix might not be as flexible as other search tools like swish++ or namazu, which you can use via the nnir back end, it has the prime advantage of being incredibly fast.  On current systems, it can easily search through headers and message bodies of thousands and thousands of mails in well under a second.  Building the database necessary for searching might take a minute or two, but only has to be done once fully.  Afterwards, the updates are done incrementally and therefore are really fast, too.  Additionally, mairix is very easy to set up.

For maximum speed though, mairix should be used with mails stored in Maildir or MH format (this includes the nnml back end), although it also works with mbox.  Mairix presents the search results by populating a virtual maildir/MH folder with symlinks which point to the ``real'' message files (if mbox is used, copies are made).  Since mairix already presents search results in such a virtual mail folder, it is very well suited for using it as an external program for creating smart mail folders, which represent certain mail searches.

nnmairix requirements
.....................

Mairix searches local mail---that means, mairix absolutely must have direct access to your mail folders.  If your mail resides on another server (e.g. an IMAP server) and you happen to have shell access, nnmairix supports running mairix remotely, e.g. via ssh.

Additionally, nnmairix only supports the following Gnus back ends: nnml, nnmaildir, and nnimap.  You must use one of these back ends for using nnmairix.  Other back ends, like nnmbox, nnfolder or nnmh, won't work.

If you absolutely must use mbox and still want to use nnmairix, you can set up a local IMAP server, which you then access via nnimap.  This is a rather massive setup for accessing some mbox files, so just change to MH or Maildir already...  However, if you're really, really passionate about using mbox, you might want to look into the package mairix.el, which comes with Emacs 23.

What nnmairix does
..................

The back end nnmairix enables you to call mairix from within Gnus, either to query mairix with a search term or to update the database.  While visiting a message in the summary buffer, you can use several pre-defined shortcuts for calling mairix, e.g. to quickly search for all mails from the sender of the current message or to display the whole thread associated with the message, even if the mails are in different folders.

Additionally, you can create permanent nnmairix groups which are bound to certain mairix searches.  This way, you can easily create a group containing mails from a certain sender, with a certain subject line or even for one specific thread based on the Message-ID.  If you check for new mail in these folders (e.g. by pressing g or M-g), they automatically update themselves by calling mairix.

You might ask why you need nnmairix at all, since mairix already creates the group, populates it with links to the mails so that you can then access it with Gnus, right?  Well, this might work, but often does not---at least not without problems.  Most probably you will get strange article counts, and sometimes you might see mails which Gnus claims have already been canceled and are inaccessible.  This is due to the fact that Gnus isn't really amused when things are happening behind its back.  Another problem can be the mail back end itself, e.g. if you use mairix with an IMAP server (I had Dovecot complaining about corrupt index files when mairix changed the contents of the search group).  Using nnmairix should circumvent these problems.

nnmairix is not really a mail back end---it's actually more like a wrapper, sitting between a ``real'' mail back end where mairix stores the searches and the Gnus front end.  You can choose between three different mail back ends for the mairix folders: nnml, nnmaildir or nnimap.  nnmairix will call the mairix binary so that the search results are stored in folders named zz_mairix-<NAME>-<NUMBER> on this mail back end, but it will present these folders in the Gnus front end only with <NAME>. You can use an existing mail back end where you already store your mail, but if you're uncomfortable with nnmairix creating new mail groups alongside your other mail, you can also create e.g. a new nnmaildir or nnml server exclusively for mairix, but then make sure those servers do not accidentally receive your new mail (see nnmairix caveats).  A special case exists if you want to use mairix remotely on an IMAP server with nnimap---here the mairix folders and your other mail must be on the same nnimap back end.

Setting up mairix
.................

First: create a backup of your mail folders (see nnmairix caveats).

Setting up mairix is easy: simply create a .mairixrc file with (at least) the following entries:

     # Your Maildir/MH base folder
     base=~/Maildir

This is the base folder for your mails.  All the following directories are relative to this base folder.  If you want to use nnmairix with nnimap, this base directory has to point to the mail directory where the IMAP server stores the mail folders!

     maildir= ... your maildir folders which should be indexed ...
     mh= ... your nnml/mh folders which should be indexed ...
     mbox = ... your mbox files which should be indexed ...

This specifies all your mail folders and mbox files (relative to the base directory!) you want to index with mairix.  Note that the nnml back end saves mails in MH format, so you have to put those directories in the mh line.  See the example at the end of this section and mairixrc's man-page for further details.

     omit=zz_mairix-*

This should make sure that you don't accidentally index the mairix search results.  You can change the prefix of these folders with the variable nnmairix-group-prefix.

     mformat= ... 'maildir' or 'mh' ...
     database= ... location of database file ...

The format setting specifies the output format for the mairix search folder.  Set this to mh if you want to access search results with nnml.  Otherwise choose maildir.

To summarize, here is my shortened .mairixrc file as an example:

     base=~/Maildir
     maildir=.personal:.work:.logcheck:.sent
     mh=../Mail/nnml/*...
     mbox=../mboxmail/mailarchive_year*
     mformat=maildir
     omit=zz_mairix-*
     database=~/.mairixdatabase

In this case, the base directory is ~/Maildir, where all my Maildir folders are stored.  As you can see, the folders are separated by colons.  If you wonder why every folder begins with a dot: this is because I use Dovecot as IMAP server, which again uses Maildir++ folders.  For testing nnmairix, I also have some nnml mail, which is saved in ~/Mail/nnml.  Since this has to be specified relative to the base directory, the ../Mail notation is needed.  Note that the line ends in *..., which means to recursively scan all files under this directory.  Without the three dots, the wildcard * will not work recursively.  I also have some old mbox files with archived mail lying around in ~/mboxmail. The other lines should be obvious.

See the man page for mairixrc for details and further options, especially regarding wildcard usage, which may be a little different than you are used to.

Now simply call mairix to create the index for the first time. Note that this may take a few minutes, but every following index will do the updates incrementally and hence is very fast.

Configuring nnmairix
....................

In group mode, type G b c (nnmairix-create-server-and-default-group).  This will ask you for all necessary information and create a nnmairix server as a foreign server.  You will have to specify the following:

  * The name of the nnmairix server---choose whatever you want.

  * The name of the back end server where mairix should store its searches.  This must be a full server name, like nnml:mymail. Just hit TAB to see the available servers.  Currently, servers which are accessed through nnmaildir, nnimap and nnml are supported.  As explained above, for locally stored mails, this can be an existing server where you store your mails. However, you can also create e.g. a new nnmaildir or nnml server exclusively for nnmairix in your secondary select methods (see Finding the News).  If you use a secondary nnml server just for mairix, make sure that you explicitly set the server variable nnml-get-new-mail to nil, or you might lose mail (see nnmairix caveats).  If you want to use mairix remotely on an IMAP server, you have to choose the corresponding nnimap server here.

  * The command to call the mairix binary.  This will usually just be mairix, but you can also choose something like ssh SERVER mairix if you want to call mairix remotely, e.g. on your IMAP server.  If you want to add some default options to mairix, you could do this here, but better use the variable nnmairix-mairix-search-options instead.

  * The name of the default search group.  This will be the group where all temporary mairix searches are stored, i.e. all searches which are not bound to permanent nnmairix groups.  Choose whatever you like.

  * If the mail back end is nnimap or nnmaildir, you will be asked if you work with Maildir++, i.e. with hidden maildir folders (=beginning with a dot).  For example, you have to answer yes here if you work with the Dovecot IMAP server.  Otherwise, you should answer no here.

nnmairix keyboard shortcuts
...........................

In group mode:

G b c
     Creates nnmairix server and default search group for this server (nnmairix-create-server-and-default-group).  You should have done this by now (see Configuring nnmairix).

G b s
     Prompts for query which is then sent to the mairix binary.  Search results are put into the default search group which is automatically displayed (nnmairix-search).

G b m
     Allows you to create a mairix search or a permanent group more comfortably using graphical widgets, similar to a customization group.  Just try it to see how it works (nnmairix-widget-search).

G b i
     Another command for creating a mairix query more comfortably, but uses only the minibuffer (nnmairix-search-interactive).

G b g
     Creates a permanent group which is associated with a search query (nnmairix-create-search-group).  The nnmairix back end automatically calls mairix when you update this group with g or M-g.

G b q
     Changes the search query for the nnmairix group under cursor (nnmairix-group-change-query-this-group).

G b t
     Toggles the 'threads' parameter for the nnmairix group under cursor, i.e.  if you want see the whole threads of the found messages (nnmairix-group-toggle-threads-this-group).

G b u
     Calls mairix binary for updating the database (nnmairix-update-database).  The default parameters are -F and -Q for making this as fast as possible (see variable nnmairix-mairix-update-options for defining these default options).

G b r
     Keep articles in this nnmairix group always read or unread, or leave the marks unchanged (nnmairix-group-toggle-readmarks-this-group).

G b d
     Recreate nnmairix group on the ``real'' mail back end (nnmairix-group-delete-recreate-this-group).  You can do this if you always get wrong article counts with a nnmairix group.

G b a
     Toggles the allow-fast parameters for group under cursor (nnmairix-group-toggle-allowfast-this-group).  The default behavior of nnmairix is to do a mairix search every time you update or enter the group.  With the allow-fast parameter set, mairix will only be called when you explicitly update the group, but not upon entering.  This makes entering the group faster, but it may also lead to dangling symlinks if something changed between updating and entering the group which is not yet in the mairix database.

G b p
     Toggle marks propagation for this group (nnmairix-group-toggle-propmarks-this-group).  (see Propagating marks).

G b o
     Manually propagate marks (nnmairix-propagate-marks); needed only when nnmairix-propagate-marks-upon-close is set to nil.

In summary mode:

$ m
     Allows you to create a mairix query or group based on the current message using graphical widgets (same as nnmairix-widget-search) (nnmairix-widget-search-from-this-article).

$ g
     Interactively creates a new search group with query based on the current message, but uses the minibuffer instead of graphical widgets (nnmairix-create-search-group-from-message).

$ t
     Searches thread for the current article (nnmairix-search-thread-this-article).  This is effectively a shortcut for calling nnmairix-search with m:msgid of the current article and enabled threads.

$ f
     Searches all messages from sender of the current article (nnmairix-search-from-this-article).  This is a shortcut for calling nnmairix-search with f:From.

$ o
     (Only in nnmairix groups!) Tries determine the group this article originally came from and displays the article in this group, so that e.g. replying to this article the correct posting styles/group parameters are applied (nnmairix-goto-original-article).  This function will use the registry if available, but can also parse the article file name as a fallback method.

$ u
     Remove possibly existing tick mark from original article (nnmairix-remove-tick-mark-original-article).  (see nnmairix tips and tricks).

Propagating marks
.................

First of: you really need a patched mairix binary for using the marks propagation feature efficiently. Otherwise, you would have to update the mairix database all the time. You can get the patch at

http://www.randomsample.de/mairix-maildir-patch.tar

You need the mairix v0.21 source code for this patch; everything else is explained in the accompanied readme file. If you don't want to use marks propagation, you don't have to apply these patches, but they also fix some annoyances regarding changing maildir flags, so it might still be useful to you.

With the patched mairix binary, you can use nnmairix as an alternative to mail splitting (see Fancy Mail Splitting). For example, instead of splitting all mails from david@foobar.com into a group, you can simply create a search group with the query f:david@foobar.com. This is actually what ``smart folders'' are all about: simply put everything in one mail folder and dynamically create searches instead of splitting. This is more flexible, since you can dynamically change your folders any time you want to. This also implies that you will usually read your mails in the nnmairix groups instead of your ``real'' mail groups.

There is one problem, though: say you got a new mail from david@foobar.com; it will now show up in two groups, the ``real'' group (your INBOX, for example) and in the nnmairix search group (provided you have updated the mairix database). Now you enter the nnmairix group and read the mail. The mail will be marked as read, but only in the nnmairix group---in the ``real'' mail group it will be still shown as unread.

You could now catch up the mail group (see Group Data), but this is tedious and error prone, since you may overlook mails you don't have created nnmairix groups for. Of course, you could first use nnmairix-goto-original-article (see nnmairix keyboard shortcuts) and then read the mail in the original group, but that's even more cumbersome.

Clearly, the easiest way would be if marks could somehow be automatically set for the original article. This is exactly what marks propagation is about.

Marks propagation is deactivated by default. You can activate it for a certain nnmairix group with nnmairix-group-toggle-propmarks-this-group (bound to G b p). This function will warn you if you try to use it with your default search group; the reason is that the default search group is used for temporary searches, and it's easy to accidentally propagate marks from this group. However, you can ignore this warning if you really want to.

With marks propagation enabled, all the marks you set in a nnmairix group should now be propagated to the original article. For example, you can now tick an article (by default with !) and this mark should magically be set for the original article, too.

A few more remarks which you may or may not want to know:

Marks will not be set immediately, but only upon closing a group. This not only makes marks propagation faster, it also avoids problems with dangling symlinks when dealing with maildir files (since changing flags will change the file name). You can also control when to propagate marks via nnmairix-propagate-marks-upon-close (see the doc-string for details).

Obviously, nnmairix will have to look up the original group for every article you want to set marks for. If available, nnmairix will first use the registry for determining the original group. The registry is very fast, hence you should really, really enable the registry when using marks propagation. If you don't have to worry about RAM and disc space, set gnus-registry-max-entries to a large enough value; to be on the safe side, choose roughly the amount of mails you index with mairix.

If you don't want to use the registry or the registry hasn't seen the original article yet, nnmairix will use an additional mairix search for determining the file name of the article. This, of course, is way slower than the registry---if you set hundreds or even thousands of marks this way, it might take some time. You can avoid this situation by setting nnmairix-only-use-registry to t.

Maybe you also want to propagate marks the other way round, i.e. if you tick an article in a "real" mail group, you'd like to have the same article in a nnmairix group ticked, too. For several good reasons, this can only be done efficiently if you use maildir. To immediately contradict myself, let me mention that it WON'T work with nnmaildir, since nnmaildir stores the marks externally and not in the file name. Therefore, propagating marks to nnmairix groups will usually only work if you use an IMAP server which uses maildir as its file format.

If you work with this setup, just set nnmairix-propagate-marks-to-nnmairix-groups to t and see what happens. If you don't like what you see, just set it to nil again. One problem might be that you get a wrong number of unread articles; this usually happens when you delete or expire articles in the original groups. When this happens, you can recreate the nnmairix group on the back end using G b d.

nnmairix tips and tricks
........................

  * Checking Mail

     I put all my important mail groups at group level 1. The mairix groups have group level 5, so they do not get checked at start up (see Group Levels).

     I use the following to check for mails:

          (defun my-check-mail-mairix-update (level)
            (interactive "P")
            ;; if no prefix given, set level=1
            (gnus-group-get-new-news (or level 1))
            (nnmairix-update-groups "mairixsearch" t t)
            (gnus-group-list-groups))

          (define-key gnus-group-mode-map "g" 'my-check-mail-mairix-update)

     Instead of "mairixsearch" use the name of your nnmairix server. See the doc string for nnmairix-update-groups for details.

  * Example: search group for ticked articles

     For example, you can create a group for all ticked articles, where the articles always stay unread:

     Hit G b g, enter group name (e.g. important), use F:f as query and do not include threads.

     Now activate marks propagation for this group by using G b p. Then activate the always-unread feature by using G b r twice.

     So far so good---but how do you remove the tick marks in the nnmairix group?  There are two options: You may simply use nnmairix-remove-tick-mark-original-article (bound to $ u) to remove tick marks from the original article. The other possibility is to set nnmairix-propagate-marks-to-nnmairix-groups to t, but see the above comments about this option.  If it works for you, the tick marks should also exist in the nnmairix group and you can remove them as usual, e.g. by marking an article as read.

     When you have removed a tick mark from the original article, this article should vanish from the nnmairix group after you have updated the mairix database and updated the group.  Fortunately, there is a function for doing exactly that: nnmairix-update-groups. See the previous code snippet and the doc string for details.

  * Dealing with auto-subscription of mail groups

     As described before, all nnmairix groups are in fact stored on the mail back end in the form zz_mairix-<NAME>-<NUMBER>. You can see them when you enter the back end server in the server buffer. You should not subscribe these groups! Unfortunately, these groups will usually get auto-subscribed when you use nnmaildir or nnml, i.e. you will suddenly see groups of the form zz_mairix* pop up in your group buffer. If this happens to you, simply kill these groups with C-k.  For avoiding this, turn off auto-subscription completely by setting the variable gnus-auto-subscribed-groups to nil (see Filtering New Groups), or if you like to keep this feature use the following kludge for turning it off for all groups beginning with zz_:

          (setq gnus-auto-subscribed-groups
                "^\\(nnml\\|nnfolder\\|nnmbox\\|nnmh\\|nnbabyl\\|nnmaildir\\).*:\\([^z]\\|z$\\|\\z[^z]\\|zz$\\|zz[^_]\\|zz_$\\).*")

nnmairix caveats
................

  * You can create a secondary nnml server just for nnmairix, but then you have to explicitly set the corresponding server variable nnml-get-new-mail to nil.  Otherwise, new mail might get put into this secondary server (and would never show up again).  Here's an example server definition:

          (nnml "mairix" (nnml-directory "mairix") (nnml-get-new-mail nil))

     (The nnmaildir back end also has a server variabe get-new-mail, but its default value is nil, so you don't have to explicitly set it if you use a nnmaildir server just for mairix.)

  * If you use the Gnus registry: don't use the registry with nnmairix groups (put them in gnus-registry-unfollowed-groups).  Be extra careful if you use gnus-registry-split-fancy-with-parent; mails which are split into nnmairix groups are usually gone for good as soon as you check the group for new mail (yes, it has happened to me...).

  * Therefore: Never ever put ``real'' mails into nnmairix groups (you shouldn't be able to, anyway).

  * If you use the Gnus agent (see Gnus Unplugged): don't agentize nnmairix groups (though I have no idea what happens if you do).

  * mairix does only support us-ascii characters.

  * nnmairix uses a rather brute force method to force Gnus to completely reread the group on the mail back end after mairix was called---it simply deletes and re-creates the group on the mail back end. So far, this has worked for me without any problems, and I don't see how nnmairix could delete other mail groups than its own, but anyway: you really should have a backup of your mail folders.

  * All necessary information is stored in the group parameters (see Group Parameters). This has the advantage that no active file is needed, but also implies that when you kill a nnmairix group, it is gone for good.

  * If you create and kill a lot of nnmairix groups, the ``zz_mairix-*'' groups will accumulate on the mail back end server. To delete old groups which are no longer needed, call nnmairix-purge-old-groups. Note that this assumes that you don't save any ``real'' mail in folders of the form zz_mairix-<NAME>-<NUMBER>. You can change the prefix of nnmairix groups by changing the variable nnmairix-group-prefix.

  * The following only applies if you don't use the mentioned patch for mairix (see Propagating marks):

     A problem can occur when using nnmairix with maildir folders and comes with the fact that maildir stores mail flags like Seen or Replied by appending chars S and R to the message file name, respectively. This implies that currently you would have to update the mairix database not only when new mail arrives, but also when mail flags are changing. The same applies to new mails which are indexed while they are still in the new folder but then get moved to cur when Gnus has seen the mail. If you don't update the database after this has happened, a mairix query can lead to symlinks pointing to non-existing files. In Gnus, these messages will usually appear with ``(none)'' entries in the header and can't be accessed. If this happens to you, using G b u and updating the group will usually fix this.

Misc Group Stuff
================

v
     The key v is reserved for users.  You can bind it to some command or better use it as a prefix key.  For example:

          (define-key gnus-group-mode-map (kbd "v j d")
            (lambda ()
              (interactive)
              (gnus-group-jump-to-group "nndraft:drafts")))

     On keys reserved for users in Emacs and on keybindings in general see Keymaps (The Emacs Editor).

^
     Enter the server buffer (gnus-group-enter-server-mode). See Server Buffer.

a
     Start composing a message (a news by default) (gnus-group-post-news).  If given a prefix, post to the group under the point.  If the prefix is 1, prompt for a group to post to. Contrary to what the name of this function suggests, the prepared article might be a mail instead of a news, if a mail group is specified with the prefix argument.  See Composing Messages.

m
     Mail a message somewhere (gnus-group-mail).  If given a prefix, use the posting style of the group under the point.  If the prefix is 1, prompt for a group name to find the posting style. See Composing Messages.

i
     Start composing a news (gnus-group-news).  If given a prefix, post to the group under the point.  If the prefix is 1, prompt for group to post to.  See Composing Messages.

     This function actually prepares a news even when using mail groups. This is useful for ``posting'' messages to mail groups without actually sending them over the network: they're just saved directly to the group in question.  The corresponding back end must have a request-post method for this to work though.

G z

     Compact the group under point (gnus-group-compact-group). Currently implemented only in nnml (see Mail Spool).  This removes gaps between article numbers, hence getting a correct total article count.

Variables for the group buffer:

gnus-group-mode-hook
     is called after the group buffer has been created.

gnus-group-prepare-hook
     is called after the group buffer is generated.  It may be used to modify the buffer in some strange, unnatural way.

gnus-group-prepared-hook
     is called as the very last thing after the group buffer has been generated.  It may be used to move point around, for instance.

gnus-permanently-visible-groups
     Groups matching this regexp will always be listed in the group buffer, whether they are empty or not.

Scanning New Messages
---------------------

g
     Check the server(s) for new articles.  If the numerical prefix is used, this command will check only groups of level ARG and lower (gnus-group-get-new-news).  If given a non-numerical prefix, this command will force a total re-reading of the active file(s) from the back end(s).

M-g
     Check whether new articles have arrived in the current group (gnus-group-get-new-news-this-group). gnus-goto-next-group-when-activating says whether this command is to move point to the next group or not.  It is t by default.

C-c M-g
     Activate absolutely all groups (gnus-activate-all-groups).

R
     Restart Gnus (gnus-group-restart).  This saves the .newsrc file(s), closes the connection to all servers, clears up all run-time Gnus variables, and then starts Gnus all over again.

gnus-get-new-news-hook is run just before checking for new news.

gnus-after-getting-new-news-hook is run after checking for new news.

Group Information
-----------------

H f
     Try to fetch the FAQ for the current group (gnus-group-fetch-faq).  Gnus will try to get the FAQ from gnus-group-faq-directory, which is usually a directory on a remote machine.  This variable can also be a list of directories. In that case, giving a prefix to this command will allow you to choose between the various sites.  ange-ftp (or efs) will be used for fetching the file.

     If fetching from the first site is unsuccessful, Gnus will attempt to go through gnus-group-faq-directory and try to open them one by one.

H d
C-c C-d
     Describe the current group (gnus-group-describe-group).  If given a prefix, force Gnus to re-read the description from the server.

M-d
     Describe all groups (gnus-group-describe-all-groups).  If given a prefix, force Gnus to re-read the description file from the server.

H v
V
     Display current Gnus version numbers (gnus-version).

?
     Give a very short help message (gnus-group-describe-briefly).

C-c C-i
     Go to the Gnus info node (gnus-info-find-node).

Group Timestamp
---------------

It can be convenient to let Gnus keep track of when you last read a group.  To set the ball rolling, you should add gnus-group-set-timestamp to gnus-select-group-hook:

     (add-hook 'gnus-select-group-hook 'gnus-group-set-timestamp)

After doing this, each time you enter a group, it'll be recorded.

This information can be displayed in various ways---the easiest is to use the %d spec in the group line format:

     (setq gnus-group-line-format
           "%M\%S\%p\%P\%5y: %(%-40,40g%) %d\n")

This will result in lines looking like:

     *        0: mail.ding                                19961002T012943
              0: custom                                   19961002T012713

As you can see, the date is displayed in compact ISO 8601 format.  This may be a bit too much, so to just display the date, you could say something like:

     (setq gnus-group-line-format
           "%M\%S\%p\%P\%5y: %(%-40,40g%) %6,6~(cut 2)d\n")

If you would like greater control of the time format, you can use a user-defined format spec.  Something like the following should do the trick:

     (setq gnus-group-line-format
           "%M\%S\%p\%P\%5y: %(%-40,40g%) %ud\n")
     (defun gnus-user-format-function-d (headers)
       (let ((time (gnus-group-timestamp gnus-tmp-group)))
         (if time
             (format-time-string "%b %d  %H:%M" time)
           "")))

File Commands
-------------

r
     Re-read the init file (gnus-init-file, which defaults to ~/.gnus.el) (gnus-group-read-init-file).

s
     Save the .newsrc.eld file (and .newsrc if wanted) (gnus-group-save-newsrc).  If given a prefix, force saving the file(s) whether Gnus thinks it is necessary or not.

Sieve Commands
--------------

Sieve is a server-side mail filtering language.  In Gnus you can use the sieve group parameter (see Group Parameters) to specify sieve rules that should apply to each group.  Gnus provides two commands to translate all these group parameters into a proper Sieve script that can be transfered to the server somehow.

The generated Sieve script is placed in gnus-sieve-file (by default ~/.sieve).  The Sieve code that Gnus generate is placed between two delimiters, gnus-sieve-region-start and gnus-sieve-region-end, so you may write additional Sieve code outside these delimiters that will not be removed the next time you regenerate the Sieve script.

The variable gnus-sieve-crosspost controls how the Sieve script is generated.  If it is non-nil (the default) articles is placed in all groups that have matching rules, otherwise the article is only placed in the group with the first matching rule.  For example, the group parameter (sieve address "sender" "owner-ding@hpc.uh.edu") will generate the following piece of Sieve code if gnus-sieve-crosspost is nil.  (When gnus-sieve-crosspost is non-nil, it looks the same except that the line containing the call to stop is removed.)

     if address "sender" "owner-ding@hpc.uh.edu" {
             fileinto "INBOX.ding";
             stop;
     }

See Emacs Sieve.

D g
     Regenerate a Sieve script from the sieve group parameters and put you into the gnus-sieve-file without saving it.

D u
     Regenerates the Gnus managed part of gnus-sieve-file using the sieve group parameters, save the file and upload it to the server using the sieveshell program.

Summary Buffer
**************

A line for each article is displayed in the summary buffer.  You can move around, read articles, post articles and reply to articles.

The most common way to a summary buffer is to select a group from the group buffer (see Selecting a Group).

You can have as many summary buffers open as you wish.

You can customize the Summary Mode tool bar, see M-x customize-apropos RET gnus-summary-tool-bar.  This feature is only available in Emacs.

The key v is reserved for users.  You can bind it to some command or better use it as a prefix key.  For example:

     (define-key gnus-summary-mode-map (kbd "v -") "LrS") ;; lower subthread

Summary Buffer Format
=====================

Gnus will use the value of the gnus-extract-address-components variable as a function for getting the name and address parts of a From header.  Two pre-defined functions exist: gnus-extract-address-components, which is the default, quite fast, and too simplistic solution; and mail-extract-address-components, which works very nicely, but is slower.  The default function will return the wrong answer in 5% of the cases.  If this is unacceptable to you, use the other function instead:

     (setq gnus-extract-address-components
           'mail-extract-address-components)

gnus-summary-same-subject is a string indicating that the current article has the same subject as the previous.  This string will be used with those specs that require it.  The default is "".

Summary Buffer Lines
--------------------

You can change the format of the lines in the summary buffer by changing the gnus-summary-line-format variable.  It works along the same lines as a normal format string, with some extensions (see Formatting Variables).

There should always be a colon or a point position marker on the line; the cursor always moves to the point position marker or the colon after performing an operation.  (Of course, Gnus wouldn't be Gnus if it wasn't possible to change this.  Just write a new function gnus-goto-colon which does whatever you like with the cursor.) See Positioning Point.

The default string is %U%R%z%I%(%[%4L: %-23,23f%]%) %s\n.

The following format specification characters and extended format specification(s) are understood:

N
     Article number.

S
     Subject string.  List identifiers stripped, gnus-list-identifiers.  See Article Hiding.

s
     Subject if the article is the root of the thread or the previous article had a different subject, gnus-summary-same-subject otherwise. (gnus-summary-same-subject defaults to "".)

F
     Full From header.

n
     The name (from the From header).

f
     The name, To header or the Newsgroups header (see To From Newsgroups).

a
     The name (from the From header).  This differs from the n spec in that it uses the function designated by the gnus-extract-address-components variable, which is slower, but may be more thorough.

A
     The address (from the From header).  This works the same way as the a spec.

L
     Number of lines in the article.

c
     Number of characters in the article.  This specifier is not supported in some methods (like nnfolder).

k
     Pretty-printed version of the number of characters in the article; for example, 1.2k or 0.4M.

I
     Indentation based on thread level (see Customizing Threading).

B
     A complex trn-style thread tree, showing response-connecting trace lines.  A thread could be drawn like this:

          >
          +->
          | +->
          | | \->
          | |   \->
          | \->
          +->
          \->

     You can customize the appearance with the following options.  Note that it is possible to make the thread display look really neat by replacing the default ASCII characters with graphic line-drawing glyphs.

     gnus-sum-thread-tree-root
          Used for the root of a thread.  If nil, use subject instead.  The default is > .

     gnus-sum-thread-tree-false-root
          Used for the false root of a thread (see Loose Threads).  If nil, use subject instead.  The default is > .

     gnus-sum-thread-tree-single-indent
          Used for a thread with just one message.  If nil, use subject instead.  The default is.

     gnus-sum-thread-tree-vertical
          Used for drawing a vertical line.  The default is | .

     gnus-sum-thread-tree-indent
          Used for indenting.  The default is   .

     gnus-sum-thread-tree-leaf-with-other
          Used for a leaf with brothers.  The default is +-> .

     gnus-sum-thread-tree-single-leaf
          Used for a leaf without brothers.  The default is \->

T
     Nothing if the article is a root and lots of spaces if it isn't (it pushes everything after it off the screen).

[
     Opening bracket, which is normally [, but can also be < for adopted articles (see Customizing Threading).

]
     Closing bracket, which is normally ], but can also be > for adopted articles.

>
     One space for each thread level.

<
     Twenty minus thread level spaces.

U
     Unread.  See Read Articles.

R
     This misleadingly named specifier is the secondary mark.  This mark will say whether the article has been replied to, has been cached, or has been saved.  See Other Marks.

i
     Score as a number (see Scoring).

z
     Zcore, + if above the default level and - if below the default level.  If the difference between gnus-summary-default-score and the score is less than gnus-summary-zcore-fuzz, this spec will not be used.

V
     Total thread score.

x
     Xref.

D
     Date.

d
     The Date in DD-MMM format.

o
     The Date in YYYYMMDDTHHMMSS format.

M
     Message-ID.

r
     References.

t
     Number of articles in the current sub-thread.  Using this spec will slow down summary buffer generation somewhat.

e
     An = (gnus-not-empty-thread-mark) will be displayed if the article has any children.

P
     The line number.

O
     Download mark.

*
     Desired cursor position (instead of after first colon).

&user-date;
     Age sensitive date format.  Various date format is defined in gnus-user-date-format-alist.

u
     User defined specifier.  The next character in the format string should be a letter.  Gnus will call the function gnus-user-format-function-X, where X is the letter following %u.  The function will be passed the current header as argument.  The function should return a string, which will be inserted into the summary just like information from any other summary specifier.

Text between %( and %) will be highlighted with gnus-mouse-face when the mouse point is placed inside the area. There can only be one such area.

The %U (status), %R (replied) and %z (zcore) specs have to be handled with care.  For reasons of efficiency, Gnus will compute what column these characters will end up in, and ``hard-code'' that.  This means that it is invalid to have these specs after a variable-length spec.  Well, you might not be arrested, but your summary buffer will look strange, which is bad enough.

The smart choice is to have these specs as far to the left as possible. (Isn't that the case with everything, though?  But I digress.)

This restriction may disappear in later versions of Gnus.

To From Newsgroups
------------------

In some groups (particularly in archive groups), the From header isn't very interesting, since all the articles there are written by you.  To display the information in the To or Newsgroups headers instead, you need to decide three things: What information to gather; where to display it; and when to display it.

 1. The reading of extra header information is controlled by the gnus-extra-headers.  This is a list of header symbols.  For instance:

          (setq gnus-extra-headers
                '(To Newsgroups X-Newsreader))

     This will result in Gnus trying to obtain these three headers, and storing it in header structures for later easy retrieval.

 2. The value of these extra headers can be accessed via the gnus-extra-header function.  Here's a format line spec that will access the X-Newsreader header:

          "%~(form (gnus-extra-header 'X-Newsreader))@"

 3. The gnus-ignored-from-addresses variable says when the %f summary line spec returns the To, Newsreader or From header.  If this regexp matches the contents of the From header, the value of the To or Newsreader headers are used instead.

     To distinguish regular articles from those where the From field has been swapped, a string is prefixed to the To or Newsgroups header in the summary line.  By default the string is ->  for To and =>  for Newsgroups, you can customize these strings with gnus-summary-to-prefix and gnus-summary-newsgroup-prefix.

A related variable is nnmail-extra-headers, which controls when to include extra headers when generating overview (NOV) files. If you have old overview files, you should regenerate them after changing this variable, by entering the server buffer using ^, and then g on the appropriate mail server (e.g. nnml) to cause regeneration.

You also have to instruct Gnus to display the data by changing the %n spec to the %f spec in the gnus-summary-line-format variable.

In summary, you'd typically put something like the following in ~/.gnus.el:

     (setq gnus-extra-headers
           '(To Newsgroups))
     (setq nnmail-extra-headers gnus-extra-headers)
     (setq gnus-summary-line-format
           "%U%R%z%I%(%[%4L: %-23,23f%]%) %s\n")
     (setq gnus-ignored-from-addresses
           "Your Name Here")

(The values listed above are the default values in Gnus.  Alter them to fit your needs.)

A note for news server administrators, or for users who wish to try to convince their news server administrator to provide some additional support:

The above is mostly useful for mail groups, where you have control over the NOV files that are created.  However, if you can persuade your nntp admin to add (in the usual implementation, notably INN):

     Newsgroups:full

to the end of her overview.fmt file, then you can use that just as you would the extra headers from the mail groups.

Summary Buffer Mode Line
------------------------

You can also change the format of the summary mode bar (see Mode Line Formatting).  Set gnus-summary-mode-line-format to whatever you like.  The default is Gnus: %%b [%A] %Z.

Here are the elements you can play with:

G
     Group name.

p
     Unprefixed group name.

A
     Current article number.

z
     Current article score.

V
     Gnus version.

U
     Number of unread articles in this group.

e
     Number of unread articles in this group that aren't displayed in the summary buffer.

Z
     A string with the number of unread and unselected articles represented either as <%U(+%e) more> if there are both unread and unselected articles, and just as <%U more> if there are just unread articles and no unselected ones.

g
     Shortish group name.  For instance, rec.arts.anime will be shortened to r.a.anime.

S
     Subject of the current article.

u
     User-defined spec (see User-Defined Specs).

s
     Name of the current score file (see Scoring).

d
     Number of dormant articles (see Unread Articles).

t
     Number of ticked articles (see Unread Articles).

r
     Number of articles that have been marked as read in this session.

E
     Number of articles expunged by the score files.

Summary Highlighting
--------------------

gnus-visual-mark-article-hook
     This hook is run after selecting an article.  It is meant to be used for highlighting the article in some way.  It is not run if gnus-visual is nil.

gnus-summary-update-hook
     This hook is called when a summary line is changed.  It is not run if gnus-visual is nil.

gnus-summary-selected-face
     This is the face (or font as some people call it) used to highlight the current article in the summary buffer.

gnus-summary-highlight
     Summary lines are highlighted according to this variable, which is a list where the elements are of the format (FORM . FACE).  If you would, for instance, like ticked articles to be italic and high-scored articles to be bold, you could set this variable to something like

          (((eq mark gnus-ticked-mark) . italic)
           ((> score default) . bold))

     As you may have guessed, if FORM returns a non-nil value, FACE will be applied to the line.

Summary Maneuvering
===================

All the straight movement commands understand the numeric prefix and behave pretty much as you'd expect.

None of these commands select articles.

G M-n
M-n
     Go to the next summary line of an unread article (gnus-summary-next-unread-subject).

G M-p
M-p
     Go to the previous summary line of an unread article (gnus-summary-prev-unread-subject).

G g
     Ask for an article number and then go to the summary line of that article without displaying the article (gnus-summary-goto-subject).

If Gnus asks you to press a key to confirm going to the next group, you can use the C-n and C-p keys to move around the group buffer, searching for the next group to read without actually returning to the group buffer.

Variables related to summary movement:

gnus-auto-select-next
     If you issue one of the movement commands (like n) and there are no more unread articles after the current one, Gnus will offer to go to the next group.  If this variable is t and the next group is empty, Gnus will exit summary mode and return to the group buffer.  If this variable is neither t nor nil, Gnus will select the next group with unread articles.  As a special case, if this variable is quietly, Gnus will select the next group without asking for confirmation.  If this variable is almost-quietly, the same will happen only if you are located on the last article in the group. Finally, if this variable is slightly-quietly, the Z n command will go to the next group without confirmation.  Also see Group Levels.

gnus-auto-select-same
     If non-nil, all the movement commands will try to go to the next article with the same subject as the current.  (Same here might mean roughly equal.  See gnus-summary-gather-subject-limit for details (see Customizing Threading).)  If there are no more articles with the same subject, go to the first unread article.

     This variable is not particularly useful if you use a threaded display.

gnus-summary-check-current
     If non-nil, all the ``unread'' movement commands will not proceed to the next (or previous) article if the current article is unread. Instead, they will choose the current article.

gnus-auto-center-summary
     If non-nil, Gnus will keep the point in the summary buffer centered at all times.  This makes things quite tidy, but if you have a slow network connection, or simply do not like this un-Emacsism, you can set this variable to nil to get the normal Emacs scrolling action.  This will also inhibit horizontal re-centering of the summary buffer, which might make it more inconvenient to read extremely long threads.

     This variable can also be a number.  In that case, center the window at the given number of lines from the top.

gnus-summary-stop-at-end-of-message
     If non-nil, don't go to the next article when hitting SPC, and you're at the end of the article.

Choosing Articles
=================

Choosing Commands
-----------------

None of the following movement commands understand the numeric prefix, and they all select and display an article.

If you want to fetch new articles or redisplay the group, see Exiting the Summary Buffer.

SPACE
     Select the current article, or, if that one's read already, the next unread article (gnus-summary-next-page).

     If you have an article window open already and you press SPACE again, the article will be scrolled.  This lets you conveniently SPACE through an entire newsgroup.  See Paging the Article.

G n
n
     Go to next unread article (gnus-summary-next-unread-article).

G p
p
     Go to previous unread article (gnus-summary-prev-unread-article).

G N
N
     Go to the next article (gnus-summary-next-article).

G P
P
     Go to the previous article (gnus-summary-prev-article).

G C-n
     Go to the next article with the same subject (gnus-summary-next-same-subject).

G C-p
     Go to the previous article with the same subject (gnus-summary-prev-same-subject).

G f
.
     Go to the first unread article (gnus-summary-first-unread-article).

G b
,
     Go to the unread article with the highest score (gnus-summary-best-unread-article).  If given a prefix argument, go to the first unread article that has a score over the default score.

G l
l
     Go to the previous article read (gnus-summary-goto-last-article).

G o
     Pop an article off the summary history and go to this article (gnus-summary-pop-article).  This command differs from the command above in that you can pop as many previous articles off the history as you like, while l toggles the two last read articles. For a somewhat related issue (if you use these commands a lot), see Article Backlog.

G j
j
     Ask for an article number or Message-ID, and then go to that article (gnus-summary-goto-article).

Choosing Variables
------------------

Some variables relevant for moving and selecting articles:

gnus-auto-extend-newsgroup
     All the movement commands will try to go to the previous (or next) article, even if that article isn't displayed in the Summary buffer if this variable is non-nil.  Gnus will then fetch the article from the server and display it in the article buffer.

gnus-select-article-hook
     This hook is called whenever an article is selected.  The default is nil.  If you would like each article to be saved in the Agent as you read it, putting gnus-agent-fetch-selected-article on this hook will do so.

gnus-mark-article-hook
     This hook is called whenever an article is selected.  It is intended to be used for marking articles as read.  The default value is gnus-summary-mark-read-and-unread-as-read, and will change the mark of almost any article you read to gnus-read-mark.  The only articles not affected by this function are ticked, dormant, and expirable articles.  If you'd instead like to just have unread articles marked as read, you can use gnus-summary-mark-unread-as-read instead.  It will leave marks like gnus-low-score-mark, gnus-del-mark (and so on) alone.

Scrolling the Article
=====================

SPACE
     Pressing SPACE will scroll the current article forward one page, or, if you have come to the end of the current article, will choose the next article (gnus-summary-next-page).

     If gnus-article-skip-boring is non-nil and the rest of the article consists only of citations and signature, then it will be skipped; the next article will be shown instead.  You can customize what is considered uninteresting with gnus-article-boring-faces.  You can manually view the article's pages, no matter how boring, using C-M-v.

DEL
     Scroll the current article back one page (gnus-summary-prev-page).

RET
     Scroll the current article one line forward (gnus-summary-scroll-up).

M-RET
     Scroll the current article one line backward (gnus-summary-scroll-down).

A g
g
     (Re)fetch the current article (gnus-summary-show-article).  If given a prefix, fetch the current article, but don't run any of the article treatment functions.  If given a prefix twice (i.e., C-u C-u g'), show a completely ``raw'' article, just the way it came from the server.

     If given a numerical prefix, you can do semi-manual charset stuff. C-u 0 g cn-gb-2312 RET will decode the message as if it were encoded in the cn-gb-2312 charset.  If you have

          (setq gnus-summary-show-article-charset-alist
                '((1 . cn-gb-2312)
                  (2 . big5)))

     then you can say C-u 1 g to get the same effect.

A <
<
     Scroll to the beginning of the article (gnus-summary-beginning-of-article).

A >
>
     Scroll to the end of the article (gnus-summary-end-of-article).

A s
s
     Perform an isearch in the article buffer (gnus-summary-isearch-article).

h
     Select the article buffer (gnus-summary-select-article-buffer).

Reply, Followup and Post
========================

Summary Mail Commands
---------------------

Commands for composing a mail message:

S r
r
     Mail a reply to the author of the current article (gnus-summary-reply).

S R
R
     Mail a reply to the author of the current article and include the original message (gnus-summary-reply-with-original).  This command uses the process/prefix convention.

S w
     Mail a wide reply to the author of the current article (gnus-summary-wide-reply).  A wide reply is a reply that goes out to all people listed in the To, From (or Reply-to) and Cc headers.  If Mail-Followup-To is present, that's used instead.

S W
     Mail a wide reply to the current article and include the original message (gnus-summary-wide-reply-with-original).  This command uses the process/prefix convention, but only uses the headers from the first article to determine the recipients.

S v
     Mail a very wide reply to the author of the current article (gnus-summary-wide-reply).  A very wide reply is a reply that goes out to all people listed in the To, From (or Reply-to) and Cc headers in all the process/prefixed articles.  This command uses the process/prefix convention.

S V
     Mail a very wide reply to the author of the current article and include the original message (gnus-summary-very-wide-reply-with-original).  This command uses the process/prefix convention.

S B r
     Mail a reply to the author of the current article but ignore the Reply-To field (gnus-summary-reply-broken-reply-to). If you need this because a mailing list incorrectly sets a Reply-To header pointing to the list, you probably want to set the broken-reply-to group parameter instead, so things will work correctly.  See Group Parameters.

S B R
     Mail a reply to the author of the current article and include the original message but ignore the Reply-To field (gnus-summary-reply-broken-reply-to-with-original).

S o m
C-c C-f
     Forward the current article to some other person (gnus-summary-mail-forward).  If no prefix is given, the message is forwarded according to the value of (message-forward-as-mime) and (message-forward-show-mml); if the prefix is 1, decode the message and forward directly inline; if the prefix is 2, forward message as an rfc822 MIME section; if the prefix is 3, decode message and forward as an rfc822 MIME section; if the prefix is 4, forward message directly inline; otherwise, the message is forwarded as no prefix given but use the flipped value of (message-forward-as-mime).  By default, the message is decoded and forwarded as an rfc822 MIME section.

S m
m
     Prepare a mail (gnus-summary-mail-other-window).  By default, use the posting style of the current group.  If given a prefix, disable that. If the prefix is 1, prompt for a group name to find the posting style.

S i
     Prepare a news (gnus-summary-news-other-window).  By default, post to the current group.  If given a prefix, disable that.  If the prefix is 1, prompt for a group to post to.

     This function actually prepares a news even when using mail groups. This is useful for ``posting'' messages to mail groups without actually sending them over the network: they're just saved directly to the group in question.  The corresponding back end must have a request-post method for this to work though.

S D b
     If you have sent a mail, but the mail was bounced back to you for some reason (wrong address, transient failure), you can use this command to resend that bounced mail (gnus-summary-resend-bounced-mail).  You will be popped into a mail buffer where you can edit the headers before sending the mail off again.  If you give a prefix to this command, and the bounced mail is a reply to some other mail, Gnus will try to fetch that mail and display it for easy perusal of its headers.  This might very well fail, though.

S D r
     Not to be confused with the previous command, gnus-summary-resend-message will prompt you for an address to send the current message off to, and then send it to that place.  The headers of the message won't be altered---but lots of headers that say Resent-To, Resent-From and so on will be added.  This means that you actually send a mail to someone that has a To header that (probably) points to yourself.  This will confuse people. So, natcherly you'll only do that if you're really eVIl.

     This command is mainly used if you have several accounts and want to ship a mail to a different account of yours.  (If you're both root and postmaster and get a mail for postmaster to the root account, you may want to resend it to postmaster.  Ordnung muss sein!

     This command understands the process/prefix convention (see Process/Prefix).

S D e

     Like the previous command, but will allow you to edit the message as if it were a new message before resending.

S O m
     Digest the current series (see Decoding Articles) and forward the result using mail (gnus-uu-digest-mail-forward).  This command uses the process/prefix convention (see Process/Prefix).

S M-c
     Send a complaint about excessive crossposting to the author of the current article (gnus-summary-mail-crosspost-complaint).

     This command is provided as a way to fight back against the current crossposting pandemic that's sweeping Usenet.  It will compose a reply using the gnus-crosspost-complaint variable as a preamble.  This command understands the process/prefix convention (see Process/Prefix) and will prompt you before sending each mail.

Also see Header Commands (The Message Manual), for more information.

Summary Post Commands
---------------------

Commands for posting a news article:

S p
a
     Prepare for posting an article (gnus-summary-post-news).  By default, post to the current group.  If given a prefix, disable that. If the prefix is 1, prompt for another group instead.

S f
f
     Post a followup to the current article (gnus-summary-followup).

S F
F
     Post a followup to the current article and include the original message (gnus-summary-followup-with-original).  This command uses the process/prefix convention.

S n
     Post a followup to the current article via news, even if you got the message through mail (gnus-summary-followup-to-mail).

S N
     Post a followup to the current article via news, even if you got the message through mail and include the original message (gnus-summary-followup-to-mail-with-original).  This command uses the process/prefix convention.

S o p
     Forward the current article to a newsgroup (gnus-summary-post-forward). If no prefix is given, the message is forwarded according to the value of (message-forward-as-mime) and (message-forward-show-mml); if the prefix is 1, decode the message and forward directly inline; if the prefix is 2, forward message as an rfc822 MIME section; if the prefix is 3, decode message and forward as an rfc822 MIME section; if the prefix is 4, forward message directly inline; otherwise, the message is forwarded as no prefix given but use the flipped value of (message-forward-as-mime).  By default, the message is decoded and forwarded as an rfc822 MIME section.

S O p
     Digest the current series and forward the result to a newsgroup (gnus-uu-digest-post-forward).  This command uses the process/prefix convention.

S u
     Uuencode a file, split it into parts, and post it as a series (gnus-uu-post-news).  (see Uuencoding and Posting).

Also see Header Commands (The Message Manual), for more information.

Summary Message Commands
------------------------

S y
     Yank the current article into an already existing Message composition buffer (gnus-summary-yank-message).  This command prompts for what message buffer you want to yank into, and understands the process/prefix convention (see Process/Prefix).

Canceling Articles
------------------

Have you ever written something, and then decided that you really, really, really wish you hadn't posted that?

Well, you can't cancel mail, but you can cancel posts.

Find the article you wish to cancel (you can only cancel your own articles, so don't try any funny stuff).  Then press C or S c (gnus-summary-cancel-article).  Your article will be canceled---machines all over the world will be deleting your article. This command uses the process/prefix convention (see Process/Prefix).

Be aware, however, that not all sites honor cancels, so your article may live on here and there, while most sites will delete the article in question.

Gnus will use the ``current'' select method when canceling.  If you want to use the standard posting method, use the a symbolic prefix (see Symbolic Prefixes).

Gnus ensures that only you can cancel your own messages using a Cancel-Lock header (see Canceling News (Message Manual)).

If you discover that you have made some mistakes and want to do some corrections, you can post a superseding article that will replace your original article.

Go to the original article and press S s (gnus-summary-supersede-article).  You will be put in a buffer where you can edit the article all you want before sending it off the usual way.

The same goes for superseding as for canceling, only more so: Some sites do not honor superseding.  On those sites, it will appear that you have posted almost the same article twice.

If you have just posted the article, and change your mind right away, there is a trick you can use to cancel/supersede the article without waiting for the article to appear on your site first.  You simply return to the post buffer (which is called *sent ...*).  There you will find the article you just posted, with all the headers intact.  Change the Message-ID header to a Cancel or Supersedes header by substituting one of those words for the word Message-ID.  Then just press C-c C-c to send the article as you would do normally.  The previous article will be canceled/superseded.

Just remember, kids: There is no 'c' in 'supersede'.

Delayed Articles
================

Sometimes, you might wish to delay the sending of a message.  For example, you might wish to arrange for a message to turn up just in time to remind your about the birthday of your Significant Other.  For this, there is the gnus-delay package.  Setup is simple:

     (gnus-delay-initialize)

Normally, to send a message you use the C-c C-c command from Message mode.  To delay a message, use C-c C-j (gnus-delay-article) instead.  This will ask you for how long the message should be delayed.  Possible answers are:

  * A time span.  Consists of an integer and a letter.  For example, 42d means to delay for 42 days.  Available letters are m (minutes), h (hours), d (days), w (weeks), M (months) and Y (years).

  * A specific date.  Looks like YYYY-MM-DD.  The message will be delayed until that day, at a specific time (eight o'clock by default). See also gnus-delay-default-hour.

  * A specific time of day.  Given in hh:mm format, 24h, no am/pm stuff.  The deadline will be at that time today, except if that time has already passed, then it's at the given time tomorrow.  So if it's ten o'clock in the morning and you specify 11:15, then the deadline is one hour and fifteen minutes hence.  But if you specify 9:20, that means a time tomorrow.

The action of the gnus-delay-article command is influenced by a couple of variables:

gnus-delay-default-hour
     When you specify a specific date, the message will be due on that hour on the given date.  Possible values are integers 0 through 23.

gnus-delay-default-delay
     This is a string and gives the default delay.  It can be of any of the formats described above.

gnus-delay-group
     Delayed articles will be kept in this group on the drafts server until they are due.  You probably don't need to change this.  The default value is "delayed".

gnus-delay-header
     The deadline for each article will be stored in a header.  This variable is a string and gives the header name.  You probably don't need to change this.  The default value is "X-Gnus-Delayed".

The way delaying works is like this: when you use the gnus-delay-article command, you give a certain delay.  Gnus calculates the deadline of the message and stores it in the X-Gnus-Delayed header and puts the message in the nndraft:delayed group.

And whenever you get new news, Gnus looks through the group for articles which are due and sends them.  It uses the gnus-delay-send-queue function for this.  By default, this function is added to the hook gnus-get-new-news-hook.  But of course, you can change this. Maybe you want to use the demon to send drafts?  Just tell the demon to execute the gnus-delay-send-queue function.

gnus-delay-initialize
     By default, this function installs gnus-delay-send-queue in gnus-get-new-news-hook.  But it accepts the optional second argument no-check.  If it is non-nil, gnus-get-new-news-hook is not changed.  The optional first argument is ignored.

     For example, (gnus-delay-initialize nil t) means to do nothing. Presumably, you want to use the demon for sending due delayed articles. Just don't forget to set that up :-)

When delaying an article with C-c C-j, Message mode will automatically add a "Date" header with the current time.  In many cases you probably want the "Date" header to reflect the time the message is sent instead.  To do this, you have to delete Date from message-draft-headers.

Marking Articles
================

There are several marks you can set on an article.

You have marks that decide the readedness (whoo, neato-keano neologism ohoy!) of the article.  Alphabetic marks generally mean read, while non-alphabetic characters generally mean unread.

In addition, you also have marks that do not affect readedness.

There's a plethora of commands for manipulating these marks.

Unread Articles
---------------

The following marks mark articles as (kinda) unread, in one form or other.

!
     Marked as ticked (gnus-ticked-mark).

     Ticked articles are articles that will remain visible always.  If you see an article that you find interesting, or you want to put off reading it, or replying to it, until sometime later, you'd typically tick it.  However, articles can be expired (from news servers by the news server software, Gnus itself never expires ticked messages), so if you want to keep an article forever, you'll have to make it persistent (see Persistent Articles).

?
     Marked as dormant (gnus-dormant-mark).

     Dormant articles will only appear in the summary buffer if there are followups to it.  If you want to see them even if they don't have followups, you can use the / D command (see Limiting). Otherwise (except for the visibility issue), they are just like ticked messages.

SPACE
     Marked as unread (gnus-unread-mark).

     Unread articles are articles that haven't been read at all yet.

Read Articles
-------------

All the following marks mark articles as read.

r
     These are articles that the user has marked as read with the d command manually, more or less (gnus-del-mark).

R
     Articles that have actually been read (gnus-read-mark).

O
     Articles that were marked as read in previous sessions and are now old (gnus-ancient-mark).

K
     Marked as killed (gnus-killed-mark).

X
     Marked as killed by kill files (gnus-kill-file-mark).

Y
     Marked as read by having too low a score (gnus-low-score-mark).

C
     Marked as read by a catchup (gnus-catchup-mark).

G
     Canceled article (gnus-canceled-mark)

Q
     Sparsely reffed article (gnus-sparse-mark).  See Customizing Threading.

M
     Article marked as read by duplicate suppression (gnus-duplicate-mark).  See Duplicate Suppression.

All these marks just mean that the article is marked as read, really. They are interpreted differently when doing adaptive scoring, though.

One more special mark, though:

E
     Marked as expirable (gnus-expirable-mark).

     Marking articles as expirable (or have them marked as such automatically) doesn't make much sense in normal groups---a user doesn't control expiring of news articles, but in mail groups, for instance, articles marked as expirable can be deleted by Gnus at any time.

Other Marks
-----------

There are some marks that have nothing to do with whether the article is read or not.

  * You can set a bookmark in the current article.  Say you are reading a long thesis on cats' urinary tracts, and have to go home for dinner before you've finished reading the thesis.  You can then set a bookmark in the article, and Gnus will jump to this bookmark the next time it encounters the article.  See Setting Marks.

  * All articles that you have replied to or made a followup to (i.e., have answered) will be marked with an A in the second column (gnus-replied-mark).

  * All articles that you have forwarded will be marked with an F in the second column (gnus-forwarded-mark).

  * Articles stored in the article cache will be marked with an * in the second column (gnus-cached-mark).  See Article Caching.

  * Articles ``saved'' (in some manner or other; not necessarily religiously) are marked with an S in the second column (gnus-saved-mark).

  * Articles that according to the server haven't been shown to the user before are marked with a N in the second column (gnus-recent-mark).  Note that not all servers support this mark, in which case it simply never appears.  Compare with gnus-unseen-mark.

  * Articles that haven't been seen before in Gnus by the user are marked with a . in the second column (gnus-unseen-mark). Compare with gnus-recent-mark.

  * When using the Gnus agent (see Agent Basics), articles may be downloaded for unplugged (offline) viewing.  If you are using the %O spec, these articles get the + mark in that spec. (The variable gnus-downloaded-mark controls which character to use.)

  * When using the Gnus agent (see Agent Basics), some articles might not have been downloaded.  Such articles cannot be viewed while you are unplugged (offline).  If you are using the %O spec, these articles get the - mark in that spec.  (The variable gnus-undownloaded-mark controls which character to use.)

  * The Gnus agent (see Agent Basics) downloads some articles automatically, but it is also possible to explicitly mark articles for download, even if they would not be downloaded automatically.  Such explicitly-marked articles get the % mark in the first column. (The variable gnus-downloadable-mark controls which character to use.)

  * If the %e spec is used, the presence of threads or not will be marked with gnus-not-empty-thread-mark and gnus-empty-thread-mark in the third column, respectively.

  * Finally we have the process mark (gnus-process-mark).  A variety of commands react to the presence of the process mark.  For instance, X u (gnus-uu-decode-uu) will uudecode and view all articles that have been marked with the process mark.  Articles marked with the process mark have a # in the second column.

You might have noticed that most of these ``non-readedness'' marks appear in the second column by default.  So if you have a cached, saved, replied article that you have process-marked, what will that look like?

Nothing much.  The precedence rules go as follows: process -> cache -> replied -> saved.  So if the article is in the cache and is replied, you'll only see the cache mark and not the replied mark.

Setting Marks
-------------

All the marking commands understand the numeric prefix.

M c
M-u
     Clear all readedness-marks from the current article (gnus-summary-clear-mark-forward).  In other words, mark the article as unread.

M t
!
     Tick the current article (gnus-summary-tick-article-forward). See Article Caching.

M ?
?
     Mark the current article as dormant (gnus-summary-mark-as-dormant).  See Article Caching.

M d
d
     Mark the current article as read (gnus-summary-mark-as-read-forward).

D
     Mark the current article as read and move point to the previous line (gnus-summary-mark-as-read-backward).

M k
k
     Mark all articles that have the same subject as the current one as read, and then select the next unread article (gnus-summary-kill-same-subject-and-select).

M K
C-k
     Mark all articles that have the same subject as the current one as read (gnus-summary-kill-same-subject).

M C
     Mark all unread articles as read (gnus-summary-catchup).

M C-c
     Mark all articles in the group as read---even the ticked and dormant articles (gnus-summary-catchup-all).

M H
     Catchup the current group to point (before the point) (gnus-summary-catchup-to-here).

M h
     Catchup the current group from point (after the point) (gnus-summary-catchup-from-here).

C-w
     Mark all articles between point and mark as read (gnus-summary-mark-region-as-read).

M V k
     Kill all articles with scores below the default score (or below the numeric prefix) (gnus-summary-kill-below).

M e
E
     Mark the current article as expirable (gnus-summary-mark-as-expirable).

M b
     Set a bookmark in the current article (gnus-summary-set-bookmark).

M B
     Remove the bookmark from the current article (gnus-summary-remove-bookmark).

M V c
     Clear all marks from articles with scores over the default score (or over the numeric prefix) (gnus-summary-clear-above).

M V u
     Tick all articles with scores over the default score (or over the numeric prefix) (gnus-summary-tick-above).

M V m
     Prompt for a mark, and mark all articles with scores over the default score (or over the numeric prefix) with this mark (gnus-summary-clear-above).

The gnus-summary-goto-unread variable controls what action should be taken after setting a mark.  If non-nil, point will move to the next/previous unread article.  If nil, point will just move one line up or down.  As a special case, if this variable is never, all the marking commands as well as other commands (like SPACE) will move to the next article, whether it is unread or not. The default is t.

Generic Marking Commands
------------------------

Some people would like the command that ticks an article (!) go to the next article.  Others would like it to go to the next unread article.  Yet others would like it to stay on the current article.  And even though I haven't heard of anybody wanting it to go to the previous (unread) article, I'm sure there are people that want that as well.

Multiply these five behaviors with five different marking commands, and you get a potentially complex set of variable to control what each command should do.

To sidestep that mess, Gnus provides commands that do all these different things.  They can be found on the M M map in the summary buffer.  Type M M C-h to see them all---there are too many of them to list in this manual.

While you can use these commands directly, most users would prefer altering the summary mode keymap.  For instance, if you would like the ! command to go to the next article instead of the next unread article, you could say something like:

     (add-hook 'gnus-summary-mode-hook 'my-alter-summary-map)
     (defun my-alter-summary-map ()
       (local-set-key "!" 'gnus-summary-put-mark-as-ticked-next))

or

     (defun my-alter-summary-map ()
       (local-set-key "!" "MM!n"))

Setting Process Marks
---------------------

Process marks are displayed as # in the summary buffer, and are used for marking articles in such a way that other commands will process these articles.  For instance, if you process mark four articles and then use the * command, Gnus will enter these four articles into the cache.  For more information, see Process/Prefix.

M P p
#
     Mark the current article with the process mark (gnus-summary-mark-as-processable).

M P u
M-#
     Remove the process mark, if any, from the current article (gnus-summary-unmark-as-processable).

M P U
     Remove the process mark from all articles (gnus-summary-unmark-all-processable).

M P i
     Invert the list of process marked articles (gnus-uu-invert-processable).

M P R
     Mark articles that have a Subject header that matches a regular expression (gnus-uu-mark-by-regexp).

M P G
     Unmark articles that have a Subject header that matches a regular expression (gnus-uu-unmark-by-regexp).

M P r
     Mark articles in region (gnus-uu-mark-region).

M P g
     Unmark articles in region (gnus-uu-unmark-region).

M P t
     Mark all articles in the current (sub)thread (gnus-uu-mark-thread).

M P T
     Unmark all articles in the current (sub)thread (gnus-uu-unmark-thread).

M P v
     Mark all articles that have a score above the prefix argument (gnus-uu-mark-over).

M P s
     Mark all articles in the current series (gnus-uu-mark-series).

M P S
     Mark all series that have already had some articles marked (gnus-uu-mark-sparse).

M P a
     Mark all articles in series order (gnus-uu-mark-all).

M P b
     Mark all articles in the buffer in the order they appear (gnus-uu-mark-buffer).

M P k
     Push the current process mark set onto the stack and unmark all articles (gnus-summary-kill-process-mark).

M P y
     Pop the previous process mark set from the stack and restore it (gnus-summary-yank-process-mark).

M P w
     Push the current process mark set onto the stack (gnus-summary-save-process-mark).

Also see the & command in Searching for Articles, for how to set process marks based on article body contents.

Limiting
========

It can be convenient to limit the summary buffer to just show some subset of the articles currently in the group.  The effect most limit commands have is to remove a few (or many) articles from the summary buffer.

Limiting commands work on subsets of the articles already fetched from the servers.  These commands don't query the server for additional articles.

/ /
/ s
     Limit the summary buffer to articles that match some subject (gnus-summary-limit-to-subject).  If given a prefix, exclude matching articles.

/ a
     Limit the summary buffer to articles that match some author (gnus-summary-limit-to-author).  If given a prefix, exclude matching articles.

/ R
     Limit the summary buffer to articles that match some recipient (gnus-summary-limit-to-recipient).  If given a prefix, exclude matching articles.

/ A
     Limit the summary buffer to articles in which contents of From, To or Cc header match a given address (gnus-summary-limit-to-address).  If given a prefix, exclude matching articles.

/ S
     Limit the summary buffer to articles that aren't part of any displayed threads (gnus-summary-limit-to-singletons).  If given a prefix, limit to articles that are part of displayed threads.

/ x
     Limit the summary buffer to articles that match one of the ``extra'' headers (see To From Newsgroups) (gnus-summary-limit-to-extra).  If given a prefix, exclude matching articles.

/ u
x
     Limit the summary buffer to articles not marked as read (gnus-summary-limit-to-unread).  If given a prefix, limit the buffer to articles strictly unread.  This means that ticked and dormant articles will also be excluded.

/ m
     Ask for a mark and then limit to all articles that have been marked with that mark (gnus-summary-limit-to-marks).

/ t
     Ask for a number and then limit the summary buffer to articles older than (or equal to) that number of days (gnus-summary-limit-to-age).  If given a prefix, limit to articles younger than that number of days.

/ n
     With prefix n, limit the summary buffer to the next n articles.  If not given a prefix, use the process marked articles instead.  (gnus-summary-limit-to-articles).

/ w
     Pop the previous limit off the stack and restore it (gnus-summary-pop-limit).  If given a prefix, pop all limits off the stack.

/ .
     Limit the summary buffer to the unseen articles (gnus-summary-limit-to-unseen).

/ v
     Limit the summary buffer to articles that have a score at or above some score (gnus-summary-limit-to-score).

/ p
     Limit the summary buffer to articles that satisfy the display group parameter predicate (gnus-summary-limit-to-display-predicate).  See Group Parameters, for more on this predicate.

/ r
     Limit the summary buffer to replied articles (gnus-summary-limit-to-replied).  If given a prefix, exclude replied articles.

/ E
M S
     Include all expunged articles in the limit (gnus-summary-limit-include-expunged).

/ D
     Include all dormant articles in the limit (gnus-summary-limit-include-dormant).

/ *
     Include all cached articles in the limit (gnus-summary-limit-include-cached).

/ d
     Exclude all dormant articles from the limit (gnus-summary-limit-exclude-dormant).

/ M
     Exclude all marked articles (gnus-summary-limit-exclude-marks).

/ T
     Include all the articles in the current thread in the limit.

/ c
     Exclude all dormant articles that have no children from the limit

     (gnus-summary-limit-exclude-childless-dormant).

/ C
     Mark all excluded unread articles as read (gnus-summary-limit-mark-excluded-as-read).  If given a prefix, also mark excluded ticked and dormant articles as read.

/ b
     Limit the summary buffer to articles that have bodies that match a certain regexp (gnus-summary-limit-to-bodies).  If given a prefix, reverse the limit.  This command is quite slow since it requires selecting each article to find the matches.

/ h
     Like the previous command, only limit to headers instead (gnus-summary-limit-to-headers).

The following commands aren't limiting commands, but use the / prefix as well.

/ N
     Insert all new articles in the summary buffer.  It scans for new emails if BACK-END-get-new-mail is non-nil.

/ o
     Insert all old articles in the summary buffer.  If given a numbered prefix, fetch this number of articles.

Threading
=========

Gnus threads articles by default.  To thread is to put responses to articles directly after the articles they respond to---in a hierarchical fashion.

Threading is done by looking at the References headers of the articles.  In a perfect world, this would be enough to build pretty trees, but unfortunately, the References header is often broken or simply missing.  Weird news propagation exacerbates the problem, so one has to employ other heuristics to get pleasing results.  A plethora of approaches exists, as detailed in horrible detail in Customizing Threading.

First, a quick overview of the concepts:

root
     The top-most article in a thread; the first article in the thread.

thread
     A tree-like article structure.

sub-thread
     A small(er) section of this tree-like structure.

loose threads
     Threads often lose their roots due to article expiry, or due to the root already having been read in a previous session, and not displayed in the summary buffer.  We then typically have many sub-threads that really belong to one thread, but are without connecting roots.  These are called loose threads.

thread gathering
     An attempt to gather loose threads into bigger threads.

sparse threads
     A thread where the missing articles have been ``guessed'' at, and are displayed as empty lines in the summary buffer.

Customizing Threading
---------------------

Loose Threads
.............

gnus-summary-make-false-root
     If non-nil, Gnus will gather all loose subtrees into one big tree and create a dummy root at the top.  (Wait a minute.  Root at the top? Yup.)  Loose subtrees occur when the real root has expired, or you've read or killed the root in a previous session.

     When there is no real root of a thread, Gnus will have to fudge something.  This variable says what fudging method Gnus should use. There are four possible values:

     adopt
          Gnus will make the first of the orphaned articles the parent.  This parent will adopt all the other articles.  The adopted articles will be marked as such by pointy brackets (<>) instead of the standard square brackets ([]).  This is the default method.

     dummy
          Gnus will create a dummy summary line that will pretend to be the parent.  This dummy line does not correspond to any real article, so selecting it will just select the first real article after the dummy article.  gnus-summary-dummy-line-format is used to specify the format of the dummy roots.  It accepts only one format spec:  S, which is the subject of the article.  See Formatting Variables. If you want all threads to have a dummy root, even the non-gathered ones, set gnus-summary-make-false-root-always to t.

     empty
          Gnus won't actually make any article the parent, but simply leave the subject field of all orphans except the first empty.  (Actually, it will use gnus-summary-same-subject as the subject (see Summary Buffer Format).)

     none
          Don't make any article parent at all.  Just gather the threads and display them after one another.

     nil
          Don't gather loose threads.

gnus-summary-gather-subject-limit
     Loose threads are gathered by comparing subjects of articles.  If this variable is nil, Gnus requires an exact match between the subjects of the loose threads before gathering them into one big super-thread.  This might be too strict a requirement, what with the presence of stupid newsreaders that chop off long subject lines.  If you think so, set this variable to, say, 20 to require that only the first 20 characters of the subjects have to match.  If you set this variable to a really low number, you'll find that Gnus will gather everything in sight into one thread, which isn't very helpful.

     If you set this variable to the special value fuzzy, Gnus will use a fuzzy string comparison algorithm on the subjects (see Fuzzy Matching).

gnus-simplify-subject-fuzzy-regexp
     This can either be a regular expression or list of regular expressions that match strings that will be removed from subjects if fuzzy subject simplification is used.

gnus-simplify-ignored-prefixes
     If you set gnus-summary-gather-subject-limit to something as low as 10, you might consider setting this variable to something sensible:

          (setq gnus-simplify-ignored-prefixes
                (concat
                 "\\`\\[?\\("
                 (mapconcat
                  'identity
                  '("looking"
                    "wanted" "followup" "summary\\( of\\)?"
                    "help" "query" "problem" "question"
                    "answer" "reference" "announce"
                    "How can I" "How to" "Comparison of"
                    ;; ...
                    )
                  "\\|")
                 "\\)\\s *\\("
                 (mapconcat 'identity
                            '("for" "for reference" "with" "about")
                            "\\|")
                 "\\)?\\]?:?[ \t]*"))

     All words that match this regexp will be removed before comparing two subjects.

gnus-simplify-subject-functions
     If non-nil, this variable overrides gnus-summary-gather-subject-limit.  This variable should be a list of functions to apply to the Subject string iteratively to arrive at the simplified version of the string.

     Useful functions to put in this list include:

     gnus-simplify-subject-re
          Strip the leading Re:.

     gnus-simplify-subject-fuzzy
          Simplify fuzzily.

     gnus-simplify-whitespace
          Remove excessive whitespace.

     gnus-simplify-all-whitespace
          Remove all whitespace.

     You may also write your own functions, of course.

gnus-summary-gather-exclude-subject
     Since loose thread gathering is done on subjects only, that might lead to many false hits, especially with certain common subjects like and (none).  To make the situation slightly better, you can use the regexp gnus-summary-gather-exclude-subject to say what subjects should be excluded from the gathering process.

     The default is ^ *$\\|^(none)$.

gnus-summary-thread-gathering-function
     Gnus gathers threads by looking at Subject headers.  This means that totally unrelated articles may end up in the same ``thread'', which is confusing.  An alternate approach is to look at all the Message-IDs in all the References headers to find matches. This will ensure that no gathered threads ever include unrelated articles, but it also means that people who have posted with broken newsreaders won't be gathered properly.  The choice is yours---plague or cholera:

     gnus-gather-threads-by-subject
          This function is the default gathering function and looks at Subjects exclusively.

     gnus-gather-threads-by-references
          This function looks at References headers exclusively.

     If you want to test gathering by References, you could say something like:

          (setq gnus-summary-thread-gathering-function
                'gnus-gather-threads-by-references)

Filling In Threads
..................

gnus-fetch-old-headers
     If non-nil, Gnus will attempt to build old threads by fetching more old headers---headers to articles marked as read.  If you would like to display as few summary lines as possible, but still connect as many loose threads as possible, you should set this variable to some or a number.  If you set it to a number, no more than that number of extra old headers will be fetched.  In either case, fetching old headers only works if the back end you are using carries overview files---this would normally be nntp, nnspool, nnml, and nnmaildir.  Also remember that if the root of the thread has been expired by the server, there's not much Gnus can do about that.

     This variable can also be set to invisible.  This won't have any visible effects, but is useful if you use the A T command a lot (see Finding the Parent).

     The server has to support NOV for any of this to work.

     This feature can seriously impact performance it ignores all locally cached header entries.  Setting it to t for groups for a server that doesn't expire articles (such as news.gmane.org), leads to very slow summary generation.

gnus-fetch-old-ephemeral-headers
     Same as gnus-fetch-old-headers, but only used for ephemeral newsgroups.

gnus-build-sparse-threads
     Fetching old headers can be slow.  A low-rent similar effect can be gotten by setting this variable to some.  Gnus will then look at the complete References headers of all articles and try to string together articles that belong in the same thread.  This will leave gaps in the threading display where Gnus guesses that an article is missing from the thread.  (These gaps appear like normal summary lines.  If you select a gap, Gnus will try to fetch the article in question.)  If this variable is t, Gnus will display all these ``gaps'' without regard for whether they are useful for completing the thread or not.  Finally, if this variable is more, Gnus won't cut off sparse leaf nodes that don't lead anywhere.  This variable is nil by default.

gnus-read-all-available-headers
     This is a rather obscure variable that few will find useful.  It's intended for those non-news newsgroups where the back end has to fetch quite a lot to present the summary buffer, and where it's impossible to go back to parents of articles.  This is mostly the case in the web-based groups.

     If you don't use those, then it's safe to leave this as the default nil.  If you want to use this variable, it should be a regexp that matches the group name, or t for all groups.

More Threading
..............

gnus-show-threads
     If this variable is nil, no threading will be done, and all of the rest of the variables here will have no effect.  Turning threading off will speed group selection up a bit, but it is sure to make reading slower and more awkward.

gnus-thread-hide-subtree
     If non-nil, all threads will be hidden when the summary buffer is generated.

     This can also be a predicate specifier (see Predicate Specifiers). Available predicates are gnus-article-unread-p and gnus-article-unseen-p.

     Here's an example:

          (setq gnus-thread-hide-subtree
                '(or gnus-article-unread-p
                     gnus-article-unseen-p))

     (It's a pretty nonsensical example, since all unseen articles are also unread, but you get my drift.)

gnus-thread-expunge-below
     All threads that have a total score (as defined by gnus-thread-score-function) less than this number will be expunged.  This variable is nil by default, which means that no threads are expunged.

gnus-thread-hide-killed
     if you kill a thread and this variable is non-nil, the subtree will be hidden.

gnus-thread-ignore-subject
     Sometimes somebody changes the subject in the middle of a thread.  If this variable is non-nil, which is the default, the subject change is ignored.  If it is nil, a change in the subject will result in a new thread.

gnus-thread-indent-level
     This is a number that says how much each sub-thread should be indented. The default is 4.

gnus-sort-gathered-threads-function
     Sometimes, particularly with mailing lists, the order in which mails arrive locally is not necessarily the same as the order in which they arrived on the mailing list.  Consequently, when sorting sub-threads using the default gnus-thread-sort-by-number, responses can end up appearing before the article to which they are responding to. Setting this variable to an alternate value (e.g. gnus-thread-sort-by-date), in a group's parameters or in an appropriate hook (e.g. gnus-summary-generate-hook) can produce a more logical sub-thread ordering in such instances.

Low-Level Threading
...................

gnus-parse-headers-hook
     Hook run before parsing any headers.

gnus-alter-header-function
     If non-nil, this function will be called to allow alteration of article header structures.  The function is called with one parameter, the article header vector, which it may alter in any way.  For instance, if you have a mail-to-news gateway which alters the Message-IDs in systematic ways (by adding prefixes and such), you can use this variable to un-scramble the Message-IDs so that they are more meaningful.  Here's one example:

          (setq gnus-alter-header-function 'my-alter-message-id)

          (defun my-alter-message-id (header)
            (let ((id (mail-header-id header)))
              (when (string-match
                     "\\(<[^<>@]*\\)\\.?cygnus\\..*@\\([^<>@]*>\\)" id)
                (mail-header-set-id
                 (concat (match-string 1 id) "@" (match-string 2 id))
                 header))))

Thread Commands
---------------

T k
C-M-k
     Mark all articles in the current (sub-)thread as read (gnus-summary-kill-thread).  If the prefix argument is positive, remove all marks instead.  If the prefix argument is negative, tick articles instead.

T l
C-M-l
     Lower the score of the current (sub-)thread (gnus-summary-lower-thread).

T i
     Increase the score of the current (sub-)thread (gnus-summary-raise-thread).

T #
     Set the process mark on the current (sub-)thread (gnus-uu-mark-thread).

T M-#
     Remove the process mark from the current (sub-)thread (gnus-uu-unmark-thread).

T T
     Toggle threading (gnus-summary-toggle-threads).

T s
     Expose the (sub-)thread hidden under the current article, if any

     (gnus-summary-show-thread).

T h
     Hide the current (sub-)thread (gnus-summary-hide-thread).

T S
     Expose all hidden threads (gnus-summary-show-all-threads).

T H
     Hide all threads (gnus-summary-hide-all-threads).

T t
     Re-thread the current article's thread (gnus-summary-rethread-current).  This works even when the summary buffer is otherwise unthreaded.

T ^
     Make the current article the child of the marked (or previous) article (gnus-summary-reparent-thread).

T M-^
     Make the current article the parent of the marked articles (gnus-summary-reparent-children).

The following commands are thread movement commands.  They all understand the numeric prefix.

T n
C-M-f
M-down
     Go to the next thread (gnus-summary-next-thread).

T p
C-M-b
M-up
     Go to the previous thread (gnus-summary-prev-thread).

T d
     Descend the thread (gnus-summary-down-thread).

T u
     Ascend the thread (gnus-summary-up-thread).

T o
     Go to the top of the thread (gnus-summary-top-thread).

If you ignore subject while threading, you'll naturally end up with threads that have several different subjects in them.  If you then issue a command like T k (gnus-summary-kill-thread) you might not wish to kill the entire thread, but just those parts of the thread that have the same subject as the current article.  If you like this idea, you can fiddle with gnus-thread-operation-ignore-subject.  If it is non-nil (which it is by default), subjects will be ignored when doing thread commands.  If this variable is nil, articles in the same thread with different subjects will not be included in the operation in question.  If this variable is fuzzy, only articles that have subjects fuzzily equal will be included (see Fuzzy Matching).

Sorting the Summary Buffer
==========================

If you are using a threaded summary display, you can sort the threads by setting gnus-thread-sort-functions, which can be either a single function, a list of functions, or a list containing functions and (not some-function) elements.

By default, sorting is done on article numbers.  Ready-made sorting predicate functions include gnus-thread-sort-by-number, gnus-thread-sort-by-author, gnus-thread-sort-by-recipient, gnus-thread-sort-by-subject, gnus-thread-sort-by-date, gnus-thread-sort-by-score, gnus-thread-sort-by-most-recent-number, gnus-thread-sort-by-most-recent-date, gnus-thread-sort-by-random and gnus-thread-sort-by-total-score.

Each function takes two threads and returns non-nil if the first thread should be sorted before the other.  Note that sorting really is normally done by looking only at the roots of each thread.

If you use more than one function, the primary sort key should be the last function in the list.  You should probably always include gnus-thread-sort-by-number in the list of sorting functions---preferably first.  This will ensure that threads that are equal with respect to the other sort criteria will be displayed in ascending article order.

If you would like to sort by reverse score, then by subject, and finally by number, you could do something like:

     (setq gnus-thread-sort-functions
           '(gnus-thread-sort-by-number
             gnus-thread-sort-by-subject
             (not gnus-thread-sort-by-total-score)))

The threads that have highest score will be displayed first in the summary buffer.  When threads have the same score, they will be sorted alphabetically.  The threads that have the same score and the same subject will be sorted by number, which is (normally) the sequence in which the articles arrived.

If you want to sort by score and then reverse arrival order, you could say something like:

     (setq gnus-thread-sort-functions
           '((not gnus-thread-sort-by-number)
             gnus-thread-sort-by-score))

The function in the gnus-thread-score-function variable (default +) is used for calculating the total score of a thread.  Useful functions might be max, min, or squared means, or whatever tickles your fancy.

If you are using an unthreaded display for some strange reason or other, you have to fiddle with the gnus-article-sort-functions variable.  It is very similar to the gnus-thread-sort-functions, except that it uses slightly different functions for article comparison.  Available sorting predicate functions are gnus-article-sort-by-number, gnus-article-sort-by-author, gnus-article-sort-by-subject, gnus-article-sort-by-date, gnus-article-sort-by-random, and gnus-article-sort-by-score.

If you want to sort an unthreaded summary display by subject, you could say something like:

     (setq gnus-article-sort-functions
           '(gnus-article-sort-by-number
             gnus-article-sort-by-subject))

You can define group specific sorting via gnus-parameters, see Group Parameters.

Asynchronous Article Fetching
=============================

If you read your news from an NNTP server that's far away, the network latencies may make reading articles a chore.  You have to wait for a while after pressing n to go to the next article before the article appears.  Why can't Gnus just go ahead and fetch the article while you are reading the previous one?  Why not, indeed.

First, some caveats.  There are some pitfalls to using asynchronous article fetching, especially the way Gnus does it.

Let's say you are reading article 1, which is short, and article 2 is quite long, and you are not interested in reading that.  Gnus does not know this, so it goes ahead and fetches article 2.  You decide to read article 3, but since Gnus is in the process of fetching article 2, the connection is blocked.

To avoid these situations, Gnus will open two (count 'em two) connections to the server.  Some people may think this isn't a very nice thing to do, but I don't see any real alternatives.  Setting up that extra connection takes some time, so Gnus startup will be slower.

Gnus will fetch more articles than you will read.  This will mean that the link between your machine and the NNTP server will become more loaded than if you didn't use article pre-fetch.  The server itself will also become more loaded---both with the extra article requests, and the extra connection.

Ok, so now you know that you shouldn't really use this thing... unless you really want to.

Here's how:  Set gnus-asynchronous to t.  The rest should happen automatically.

You can control how many articles are to be pre-fetched by setting gnus-use-article-prefetch.  This is 30 by default, which means that when you read an article in the group, the back end will pre-fetch the next 30 articles.  If this variable is t, the back end will pre-fetch all the articles it can without bound.  If it is nil, no pre-fetching will be done.

There are probably some articles that you don't want to pre-fetch---read articles, for instance.  The gnus-async-prefetch-article-p variable controls whether an article is to be pre-fetched.  This function should return non-nil when the article in question is to be pre-fetched.  The default is gnus-async-unread-p, which returns nil on read articles.  The function is called with an article data structure as the only parameter.

If, for instance, you wish to pre-fetch only unread articles shorter than 100 lines, you could say something like:

     (defun my-async-short-unread-p (data)
       "Return non-nil for short, unread articles."
       (and (gnus-data-unread-p data)
            (< (mail-header-lines (gnus-data-header data))
               100)))

     (setq gnus-async-prefetch-article-p 'my-async-short-unread-p)

These functions will be called many, many times, so they should preferably be short and sweet to avoid slowing down Gnus too much. It's probably a good idea to byte-compile things like this.

After an article has been prefetched, this gnus-async-post-fetch-function will be called.  The buffer will be narrowed to the region of the article that was fetched.  A useful value would be gnus-html-prefetch-images, which will prefetch and store images referenced in the article, so that you don't have to wait for them to be fetched when you read the article.  This is useful for HTML messages that have external images.

Articles have to be removed from the asynch buffer sooner or later.  The gnus-prefetched-article-deletion-strategy says when to remove articles.  This is a list that may contain the following elements:

read
     Remove articles when they are read.

exit
     Remove articles when exiting the group.

The default value is (read exit).

Article Caching
===============

If you have an extremely slow NNTP connection, you may consider turning article caching on.  Each article will then be stored locally under your home directory.  As you may surmise, this could potentially use huge amounts of disk space, as well as eat up all your inodes so fast it will make your head swim.  In vodka.

Used carefully, though, it could be just an easier way to save articles.

To turn caching on, set gnus-use-cache to t.  By default, all articles ticked or marked as dormant will then be copied over to your local cache (gnus-cache-directory).  Whether this cache is flat or hierarchical is controlled by the gnus-use-long-file-name variable, as usual.

When re-selecting a ticked or dormant article, it will be fetched from the cache instead of from the server.  As articles in your cache will never expire, this might serve as a method of saving articles while still keeping them where they belong.  Just mark all articles you want to save as dormant, and don't worry.

When an article is marked as read, is it removed from the cache.

The entering/removal of articles from the cache is controlled by the gnus-cache-enter-articles and gnus-cache-remove-articles variables.  Both are lists of symbols.  The first is (ticked dormant) by default, meaning that ticked and dormant articles will be put in the cache.  The latter is (read) by default, meaning that articles marked as read are removed from the cache.  Possibly symbols in these two lists are ticked, dormant, unread and read.

So where does the massive article-fetching and storing come into the picture?  The gnus-jog-cache command will go through all subscribed newsgroups, request all unread articles, score them, and store them in the cache.  You should only ever, ever ever ever, use this command if 1) your connection to the NNTP server is really, really, really slow and 2) you have a really, really, really huge disk. Seriously.  One way to cut down on the number of articles downloaded is to score unwanted articles down and have them marked as read.  They will not then be downloaded by this command.

It is likely that you do not want caching on all groups.  For instance, if your nnml mail is located under your home directory, it makes no sense to cache it somewhere else under your home directory.  Unless you feel that it's neat to use twice as much space.

To limit the caching, you could set gnus-cacheable-groups to a regexp of groups to cache, ^nntp for instance, or set the gnus-uncacheable-groups regexp to ^nnml, for instance. Both variables are nil by default.  If a group matches both variables, the group is not cached.

The cache stores information on what articles it contains in its active file (gnus-cache-active-file).  If this file (or any other parts of the cache) becomes all messed up for some reason or other, Gnus offers two functions that will try to set things right.  M-x gnus-cache-generate-nov-databases will (re)build all the NOV files, and gnus-cache-generate-active will (re)generate the active file.

gnus-cache-move-cache will move your whole gnus-cache-directory to some other location.  You get asked to where, isn't that cool?

Persistent Articles
===================

Closely related to article caching, we have persistent articles. In fact, it's just a different way of looking at caching, and much more useful in my opinion.

Say you're reading a newsgroup, and you happen on to some valuable gem that you want to keep and treasure forever.  You'd normally just save it (using one of the many saving commands) in some file.  The problem with that is that it's just, well, yucky.  Ideally you'd prefer just having the article remain in the group where you found it forever; untouched by the expiry going on at the news server.

This is what a persistent article is---an article that just won't be deleted.  It's implemented using the normal cache functions, but you use two explicit commands for managing persistent articles:

*
     Make the current article persistent (gnus-cache-enter-article).

M-*
     Remove the current article from the persistent articles (gnus-cache-remove-article).  This will normally delete the article.

Both these commands understand the process/prefix convention.

To avoid having all ticked articles (and stuff) entered into the cache, you should set gnus-use-cache to passive if you're just interested in persistent articles:

     (setq gnus-use-cache 'passive)

Sticky Articles
===============

When you select an article the current article buffer will be reused according to the value of the variable gnus-single-article-buffer.  If its value is non-nil (the default) all articles reuse the same article buffer.  Else each group has its own article buffer.

This implies that it's not possible to have more than one article buffer in a group at a time.  But sometimes you might want to display all the latest emails from your mother, your father, your aunt, your uncle and your 17 cousins to coordinate the next christmas party.

That's where sticky articles come in handy.  A sticky article buffer basically is a normal article buffer, but it won't be reused when you select another article.  You can make an article sticky with:

A S
     Make the current article sticky.  If a prefix arg is given, ask for a name for this sticky article buffer.

To close a sticky article buffer you can use these commands:

q
     Puts this sticky article buffer at the end of the list of all buffers.

k
     Kills this sticky article buffer.

To kill all sticky article buffers you can use:

 -- Function: gnus-kill-sticky-article-buffers ARG
     Kill all sticky article buffers. If a prefix ARG is given, ask for confirmation.

Article Backlog
===============

If you have a slow connection, but the idea of using caching seems unappealing to you (and it is, really), you can help the situation some by switching on the backlog.  This is where Gnus will buffer already read articles so that it doesn't have to re-fetch articles you've already read.  This only helps if you are in the habit of re-selecting articles you've recently read, of course.  If you never do that, turning the backlog on will slow Gnus down a little bit, and increase memory usage some.

If you set gnus-keep-backlog to a number N, Gnus will store at most N old articles in a buffer for later re-fetching.  If this variable is non-nil and is not a number, Gnus will store all read articles, which means that your Emacs will grow without bound before exploding and taking your machine down with you.  I put that in there just to keep y'all on your toes.

The default value is 20.

Saving Articles
===============

Gnus can save articles in a number of ways.  Below is the documentation for saving articles in a fairly straight-forward fashion (i.e., little processing of the article is done before it is saved).  For a different approach (uudecoding, unsharing) you should use gnus-uu (see Decoding Articles).

For the commands listed here, the target is a file.  If you want to save to a group, see the B c (gnus-summary-copy-article) command (see Mail Group Commands).

If gnus-save-all-headers is non-nil, Gnus will not delete unwanted headers before saving the article.

If the preceding variable is nil, all headers that match the gnus-saved-headers regexp will be kept, while the rest will be deleted before saving.

O o
o
     Save the current article using the default article saver (gnus-summary-save-article).

O m
     Save the current article in a Unix mail box (mbox) file (gnus-summary-save-article-mail).

O r
     Save the current article in Rmail format (gnus-summary-save-article-rmail).  This is mbox since Emacs 23, Babyl in older versions.

O f
     Save the current article in plain file format (gnus-summary-save-article-file).

O F
     Write the current article in plain file format, overwriting any previous file contents (gnus-summary-write-article-file).

O b
     Save the current article body in plain file format (gnus-summary-save-article-body-file).

O h
     Save the current article in mh folder format (gnus-summary-save-article-folder).

O v
     Save the current article in a VM folder (gnus-summary-save-article-vm).

O p
|
     Save the current article in a pipe.  Uhm, like, what I mean is---Pipe the current article to a process (gnus-summary-pipe-output). If given a symbolic prefix (see Symbolic Prefixes), include the complete headers in the piped output.  The symbolic prefix r is special; it lets this command pipe a raw article including all headers. The gnus-summary-pipe-output-default-command variable can be set to a string containing the default command and options (default nil).

O P
     Save the current article into muttprint.  That is, print it using the external program Muttprint (http://muttprint.sourceforge.net/).  The program name and options to use is controlled by the variable gnus-summary-muttprint-program. (gnus-summary-muttprint).

All these commands use the process/prefix convention (see Process/Prefix).  If you save bunches of articles using these functions, you might get tired of being prompted for files to save each and every article in.  The prompting action is controlled by the gnus-prompt-before-saving variable, which is always by default, giving you that excessive prompting action you know and loathe.  If you set this variable to t instead, you'll be prompted just once for each series of articles you save.  If you like to really have Gnus do all your thinking for you, you can even set this variable to nil, which means that you will never be prompted for files to save articles in.  Gnus will simply save all the articles in the default files.

You can customize the gnus-default-article-saver variable to make Gnus do what you want it to.  You can use any of the eight ready-made functions below, or you can create your own.

gnus-summary-save-in-rmail
     This is the default format, that used by the Rmail package.  Since Emacs 23, Rmail uses standard mbox format.  Before this, it used the Babyl format.  Accordingly, this command writes mbox format since Emacs 23, unless appending to an existing Babyl file.  In older versions of Emacs, it always uses Babyl format.  Uses the function in the gnus-rmail-save-name variable to get a file name to save the article in.  The default is gnus-plain-save-name.

gnus-summary-save-in-mail
     Save in a Unix mail (mbox) file.  Uses the function in the gnus-mail-save-name variable to get a file name to save the article in.  The default is gnus-plain-save-name.

gnus-summary-save-in-file
     Append the article straight to an ordinary file.  Uses the function in the gnus-file-save-name variable to get a file name to save the article in.  The default is gnus-numeric-save-name.

gnus-summary-write-to-file
     Write the article straight to an ordinary file.  The file is overwritten if it exists.  Uses the function in the gnus-file-save-name variable to get a file name to save the article in.  The default is gnus-numeric-save-name.

gnus-summary-save-body-in-file
     Append the article body to an ordinary file.  Uses the function in the gnus-file-save-name variable to get a file name to save the article in.  The default is gnus-numeric-save-name.

gnus-summary-write-body-to-file
     Write the article body straight to an ordinary file.  The file is overwritten if it exists.  Uses the function in the gnus-file-save-name variable to get a file name to save the article in.  The default is gnus-numeric-save-name.

gnus-summary-save-in-folder
     Save the article to an MH folder using rcvstore from the MH library.  Uses the function in the gnus-folder-save-name variable to get a file name to save the article in.  The default is gnus-folder-save-name, but you can also use gnus-Folder-save-name, which creates capitalized names.

gnus-summary-save-in-vm
     Save the article in a VM folder.  You have to have the VM mail reader to use this setting.

gnus-summary-save-in-pipe
     Pipe the article to a shell command.  This function takes optional two arguments COMMAND and RAW.  Valid values for COMMAND include:

       * a string
          The executable command name and possibly arguments.

       * nil
          You will be prompted for the command in the minibuffer.

       * the symbol default
          It will be replaced with the command which the variable gnus-summary-pipe-output-default-command holds or the command last used for saving.

     Non-nil value for RAW overrides :decode and :headers properties (see below) and the raw article including all headers will be piped.

The symbol of each function may have the following properties:

:decode
     The value non-nil means save decoded articles.  This is meaningful only with gnus-summary-save-in-file, gnus-summary-save-body-in-file, gnus-summary-write-to-file, gnus-summary-write-body-to-file, and gnus-summary-save-in-pipe.

:function
     The value specifies an alternative function which appends, not overwrites, articles to a file.  This implies that when saving many articles at a time, gnus-prompt-before-saving is bound to t and all articles are saved in a single file.  This is meaningful only with gnus-summary-write-to-file and gnus-summary-write-body-to-file.

:headers
     The value specifies the symbol of a variable of which the value specifies headers to be saved.  If it is omitted, gnus-save-all-headers and gnus-saved-headers control what headers should be saved.

All of these functions, except for the last one, will save the article in the gnus-article-save-directory, which is initialized from the SAVEDIR environment variable.  This is ~/News/ by default.

As you can see above, the functions use different functions to find a suitable name of a file to save the article in.  Below is a list of available functions that generate names:

gnus-Numeric-save-name
     File names like ~/News/Alt.andrea-dworkin/45.

gnus-numeric-save-name
     File names like ~/News/alt.andrea-dworkin/45.

gnus-Plain-save-name
     File names like ~/News/Alt.andrea-dworkin.

gnus-plain-save-name
     File names like ~/News/alt.andrea-dworkin.

gnus-sender-save-name
     File names like ~/News/larsi.

You can have Gnus suggest where to save articles by plonking a regexp into the gnus-split-methods alist.  For instance, if you would like to save articles related to Gnus in the file gnus-stuff, and articles related to VM in vm-stuff, you could set this variable to something like:

     (("^Subject:.*gnus\\|^Newsgroups:.*gnus" "gnus-stuff")
      ("^Subject:.*vm\\|^Xref:.*vm" "vm-stuff")
      (my-choosing-function "../other-dir/my-stuff")
      ((equal gnus-newsgroup-name "mail.misc") "mail-stuff"))

We see that this is a list where each element is a list that has two elements---the match and the file.  The match can either be a string (in which case it is used as a regexp to match on the article head); it can be a symbol (which will be called as a function with the group name as a parameter); or it can be a list (which will be evaled).  If any of these actions have a non-nil result, the file will be used as a default prompt.  In addition, the result of the operation itself will be used if the function or form called returns a string or a list of strings.

You basically end up with a list of file names that might be used when saving the current article.  (All ``matches'' will be used.)  You will then be prompted for what you really want to use as a name, with file name completion over the results from applying this variable.

This variable is ((gnus-article-archive-name)) by default, which means that Gnus will look at the articles it saves for an Archive-name line and use that as a suggestion for the file name.

Here's an example function to clean up file names somewhat.  If you have lots of mail groups called things like nnml:mail.whatever, you may want to chop off the beginning of these group names before creating the file name to save to.  The following will do just that:

     (defun my-save-name (group)
       (when (string-match "^nnml:mail." group)
         (substring group (match-end 0))))

     (setq gnus-split-methods
           '((gnus-article-archive-name)
             (my-save-name)))

Finally, you have the gnus-use-long-file-name variable.  If it is nil, all the preceding functions will replace all periods (.) in the group names with slashes (/)---which means that the functions will generate hierarchies of directories instead of having all the files in the top level directory (~/News/alt/andrea-dworkin instead of ~/News/alt.andrea-dworkin.)  This variable is t by default on most systems.  However, for historical reasons, this is nil on Xenix and usg-unix-v machines by default.

This function also affects kill and score file names.  If this variable is a list, and the list contains the element not-score, long file names will not be used for score files, if it contains the element not-save, long file names will not be used for saving, and if it contains the element not-kill, long file names will not be used for kill files.

If you'd like to save articles in a hierarchy that looks something like a spool, you could

     (setq gnus-use-long-file-name '(not-save)) ; to get a hierarchy
     (setq gnus-default-article-saver
           'gnus-summary-save-in-file)          ; no encoding

Then just save with o.  You'd then read this hierarchy with ephemeral nneething groups---G D in the group buffer, and the top level directory as the argument (~/News/).  Then just walk around to the groups/directories with nneething.

Decoding Articles
=================

Sometime users post articles (or series of articles) that have been encoded in some way or other.  Gnus can decode them for you.

All these functions use the process/prefix convention (see Process/Prefix) for finding out what articles to work on, with the extension that a ``single article'' means ``a single series''.  Gnus can find out by itself what articles belong to a series, decode all the articles and unpack/view/save the resulting file(s).

Gnus guesses what articles are in the series according to the following simplish rule: The subjects must be (nearly) identical, except for the last two numbers of the line.  (Spaces are largely ignored, however.)

For example: If you choose a subject called cat.gif (2/3), Gnus will find all the articles that match the regexp ^cat.gif ([0-9]+/[0-9]+).*$.

Subjects that are non-standard, like cat.gif (2/3) Part 6 of a series, will not be properly recognized by any of the automatic viewing commands, and you have to mark the articles manually with #.

Uuencoded Articles
------------------

X u
     Uudecodes the current series (gnus-uu-decode-uu).

X U
     Uudecodes and saves the current series (gnus-uu-decode-uu-and-save).

X v u
     Uudecodes and views the current series (gnus-uu-decode-uu-view).

X v U
     Uudecodes, views and saves the current series (gnus-uu-decode-uu-and-save-view).

Remember that these all react to the presence of articles marked with the process mark.  If, for instance, you'd like to decode and save an entire newsgroup, you'd typically do M P a (gnus-uu-mark-all) and then X U (gnus-uu-decode-uu-and-save).

All this is very much different from how gnus-uu worked with GNUS 4.1, where you had explicit keystrokes for everything under the sun.  This version of gnus-uu generally assumes that you mark articles in some way (see Setting Process Marks) and then press X u.

Note: When trying to decode articles that have names matching gnus-uu-notify-files, which is hard-coded to [Cc][Ii][Nn][Dd][Yy][0-9]+.\\(gif\\|jpg\\), gnus-uu will automatically post an article on comp.unix.wizards saying that you have just viewed the file in question.  This feature can't be turned off.

Shell Archives
--------------

Shell archives (``shar files'') used to be a popular way to distribute sources, but it isn't used all that much today.  In any case, we have some commands to deal with these:

X s
     Unshars the current series (gnus-uu-decode-unshar).

X S
     Unshars and saves the current series (gnus-uu-decode-unshar-and-save).

X v s
     Unshars and views the current series (gnus-uu-decode-unshar-view).

X v S
     Unshars, views and saves the current series (gnus-uu-decode-unshar-and-save-view).

PostScript Files
----------------

X p
     Unpack the current PostScript series (gnus-uu-decode-postscript).

X P
     Unpack and save the current PostScript series (gnus-uu-decode-postscript-and-save).

X v p
     View the current PostScript series (gnus-uu-decode-postscript-view).

X v P
     View and save the current PostScript series (gnus-uu-decode-postscript-and-save-view).

Other Files
-----------

X o
     Save the current series (gnus-uu-decode-save).

X b
     Unbinhex the current series (gnus-uu-decode-binhex).  This doesn't really work yet.

X Y
     yEnc-decode the current series and save it (gnus-uu-decode-yenc).

Decoding Variables
------------------

Adjective, not verb.

Rule Variables
..............

Gnus uses rule variables to decide how to view a file.  All these variables are of the form

           (list '(regexp1 command2)
                 '(regexp2 command2)
                 ...)

gnus-uu-user-view-rules
     This variable is consulted first when viewing files.  If you wish to use, for instance, sox to convert an .au sound file, you could say something like:

          (setq gnus-uu-user-view-rules
                (list '("\\\\.au$" "sox %s -t .aiff > /dev/audio")))

gnus-uu-user-view-rules-end
     This variable is consulted if Gnus couldn't make any matches from the user and default view rules.

gnus-uu-user-archive-rules
     This variable can be used to say what commands should be used to unpack archives.

Other Decode Variables
......................

gnus-uu-grabbed-file-functions
     All functions in this list will be called right after each file has been successfully decoded---so that you can move or view files right away, and don't have to wait for all files to be decoded before you can do anything.  Ready-made functions you can put in this list are:

     gnus-uu-grab-view
          View the file.

     gnus-uu-grab-move
          Move the file (if you're using a saving function.)

gnus-uu-be-dangerous
     Specifies what to do if unusual situations arise during decoding.  If nil, be as conservative as possible.  If t, ignore things that didn't work, and overwrite existing files.  Otherwise, ask each time.

gnus-uu-ignore-files-by-name
     Files with name matching this regular expression won't be viewed.

gnus-uu-ignore-files-by-type
     Files with a MIME type matching this variable won't be viewed. Note that Gnus tries to guess what type the file is based on the name. gnus-uu is not a MIME package (yet), so this is slightly kludgey.

gnus-uu-tmp-dir
     Where gnus-uu does its work.

gnus-uu-do-not-unpack-archives
     Non-nil means that gnus-uu won't peek inside archives looking for files to display.

gnus-uu-view-and-save
     Non-nil means that the user will always be asked to save a file after viewing it.

gnus-uu-ignore-default-view-rules
     Non-nil means that gnus-uu will ignore the default viewing rules.

gnus-uu-ignore-default-archive-rules
     Non-nil means that gnus-uu will ignore the default archive unpacking commands.

gnus-uu-kill-carriage-return
     Non-nil means that gnus-uu will strip all carriage returns from articles.

gnus-uu-unmark-articles-not-decoded
     Non-nil means that gnus-uu will mark unsuccessfully decoded articles as unread.

gnus-uu-correct-stripped-uucode
     Non-nil means that gnus-uu will try to fix uuencoded files that have had trailing spaces deleted.

gnus-uu-pre-uudecode-hook
     Hook run before sending a message to uudecode.

gnus-uu-view-with-metamail
     Non-nil means that gnus-uu will ignore the viewing commands defined by the rule variables and just fudge a MIME content type based on the file name.  The result will be fed to metamail for viewing.

gnus-uu-save-in-digest
     Non-nil means that gnus-uu, when asked to save without decoding, will save in digests.  If this variable is nil, gnus-uu will just save everything in a file without any embellishments.  The digesting almost conforms to RFC 1153---no easy way to specify any meaningful volume and issue numbers were found, so I simply dropped them.

Uuencoding and Posting
......................

gnus-uu-post-include-before-composing
     Non-nil means that gnus-uu will ask for a file to encode before you compose the article.  If this variable is t, you can either include an encoded file with C-c C-i or have one included for you when you post the article.

gnus-uu-post-length
     Maximum length of an article.  The encoded file will be split into how many articles it takes to post the entire file.

gnus-uu-post-threaded
     Non-nil means that gnus-uu will post the encoded file in a thread.  This may not be smart, as no other decoder I have seen is able to follow threads when collecting uuencoded articles.  (Well, I have seen one package that does that---gnus-uu, but somehow, I don't think that counts...) Default is nil.

gnus-uu-post-separate-description
     Non-nil means that the description will be posted in a separate article.  The first article will typically be numbered (0/x).  If this variable is nil, the description the user enters will be included at the beginning of the first article, which will be numbered (1/x). Default is t.

Viewing Files
-------------

After decoding, if the file is some sort of archive, Gnus will attempt to unpack the archive and see if any of the files in the archive can be viewed.  For instance, if you have a gzipped tar file pics.tar.gz containing the files pic1.jpg and pic2.gif, Gnus will uncompress and de-tar the main file, and then view the two pictures. This unpacking process is recursive, so if the archive contains archives of archives, it'll all be unpacked.

Finally, Gnus will normally insert a pseudo-article for each extracted file into the summary buffer.  If you go to these ``articles'', you will be prompted for a command to run (usually Gnus will make a suggestion), and then the command will be run.

If gnus-view-pseudo-asynchronously is nil, Emacs will wait until the viewing is done before proceeding.

If gnus-view-pseudos is automatic, Gnus will not insert the pseudo-articles into the summary buffer, but view them immediately.  If this variable is not-confirm, the user won't even be asked for a confirmation before viewing is done.

If gnus-view-pseudos-separately is non-nil, one pseudo-article will be created for each file to be viewed.  If nil, all files that use the same viewing command will be given as a list of parameters to that command.

If gnus-insert-pseudo-articles is non-nil, insert pseudo-articles when decoding.  It is t by default.

So; there you are, reading your pseudo-articles in your virtual newsgroup from the virtual server; and you think: Why isn't anything real anymore? How did we get here?

Article Treatment
=================

Reading through this huge manual, you may have quite forgotten that the object of newsreaders is to actually, like, read what people have written.  Reading articles.  Unfortunately, people are quite bad at writing, so there are tons of functions and variables to make reading these articles easier.

Article Highlighting
--------------------

Not only do you want your article buffer to look like fruit salad, but you want it to look like technicolor fruit salad.

W H a
     Do much highlighting of the current article (gnus-article-highlight).  This function highlights header, cited text, the signature, and adds buttons to the body and the head.

W H h
     Highlight the headers (gnus-article-highlight-headers).  The highlighting will be done according to the gnus-header-face-alist variable, which is a list where each element has the form (REGEXP NAME CONTENT). REGEXP is a regular expression for matching the header, NAME is the face used for highlighting the header name (see Faces and Fonts) and CONTENT is the face for highlighting the header value.  The first match made will be used.  Note that REGEXP shouldn't have ^ prepended---Gnus will add one.

W H c
     Highlight cited text (gnus-article-highlight-citation).

     Some variables to customize the citation highlights:

     gnus-cite-parse-max-size
          If the article size in bytes is bigger than this variable (which is 25000 by default), no citation highlighting will be performed.

     gnus-cite-max-prefix
          Maximum possible length for a citation prefix (default 20).

     gnus-cite-face-list
          List of faces used for highlighting citations (see Faces and Fonts). When there are citations from multiple articles in the same message, Gnus will try to give each citation from each article its own face. This should make it easier to see who wrote what.

     gnus-supercite-regexp
          Regexp matching normal Supercite attribution lines.

     gnus-supercite-secondary-regexp
          Regexp matching mangled Supercite attribution lines.

     gnus-cite-minimum-match-count
          Minimum number of identical prefixes we have to see before we believe that it's a citation.

     gnus-cite-attribution-prefix
          Regexp matching the beginning of an attribution line.

     gnus-cite-attribution-suffix
          Regexp matching the end of an attribution line.

     gnus-cite-attribution-face
          Face used for attribution lines.  It is merged with the face for the cited text belonging to the attribution.

     gnus-cite-ignore-quoted-from
          If non-nil, no citation highlighting will be performed on lines beginning with >From .  Those lines may have been quoted by MTAs in order not to mix up with the envelope From line.  The default value is t.

W H s
     Highlight the signature (gnus-article-highlight-signature). Everything after gnus-signature-separator (see Article Signature) in an article will be considered a signature and will be highlighted with gnus-signature-face, which is italic by default.

See Customizing Articles, for how to highlight articles automatically.

Article Fontisizing
-------------------

People commonly add emphasis to words in news articles by writing things like _this_ or *this* or /this/.  Gnus can make this look nicer by running the article through the W e (gnus-article-emphasize) command.

How the emphasis is computed is controlled by the gnus-emphasis-alist variable.  This is an alist where the first element is a regular expression to be matched.  The second is a number that says what regular expression grouping is used to find the entire emphasized word.  The third is a number that says what regexp grouping should be displayed and highlighted.  (The text between these two groupings will be hidden.)  The fourth is the face used for highlighting.

     (setq gnus-emphasis-alist
           '(("_\\(\\w+\\)_" 0 1 gnus-emphasis-underline)
             ("\\*\\(\\w+\\)\\*" 0 1 gnus-emphasis-bold)))

By default, there are seven rules, and they use the following faces: gnus-emphasis-bold, gnus-emphasis-italic, gnus-emphasis-underline, gnus-emphasis-bold-italic, gnus-emphasis-underline-italic, gnus-emphasis-underline-bold, and gnus-emphasis-underline-bold-italic.

If you want to change these faces, you can either use M-x customize, or you can use copy-face.  For instance, if you want to make gnus-emphasis-italic use a red face instead, you could say something like:

     (copy-face 'red 'gnus-emphasis-italic)

If you want to highlight arbitrary words, you can use the gnus-group-highlight-words-alist variable, which uses the same syntax as gnus-emphasis-alist.  The highlight-words group parameter (see Group Parameters) can also be used.

See Customizing Articles, for how to fontize articles automatically.

Article Hiding
--------------

Or rather, hiding certain things in each article.  There usually is much too much cruft in most articles.

W W a
     Do quite a lot of hiding on the article buffer (gnus-article-hide).  In particular, this function will hide headers, PGP, cited text and the signature.

W W h
     Hide headers (gnus-article-hide-headers).  See Hiding Headers.

W W b
     Hide headers that aren't particularly interesting (gnus-article-hide-boring-headers).  See Hiding Headers.

W W s
     Hide signature (gnus-article-hide-signature).  See Article Signature.

W W l
     Strip list identifiers specified in gnus-list-identifiers.  These are strings some mailing list servers add to the beginning of all Subject headers---for example, [zebra 4711].  Any leading Re:  is skipped before stripping.  gnus-list-identifiers may not contain \\(..\\).

     gnus-list-identifiers
          A regular expression that matches list identifiers to be removed from subject.  This can also be a list of regular expressions.

W W P
     Hide PEM (privacy enhanced messages) cruft (gnus-article-hide-pem).

W W B