[apps/madmutt.git] / doc / manual.xml.head

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<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN"
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<book>

<bookinfo>
  <title>The Mutt Next Generation E-Mail Client</title>
  <author>
    <firstname>Andreas</firstname><surname>Krennmair</surname>
    <email>ak@synflood.at</email>
  </author>
  <author>
    <firstname>Michael</firstname><surname>Elkins</surname>
    <email>me@cs.hmc.edu</email>
  </author>
  <pubdate>version devel-r473</pubdate>
  <abstract>
    <para>
      Michael Elinks on mutt, circa 1995:
      ``All mail clients suck. This one just sucks less.''
    </para>
    <para>
      Sven Guckes on mutt, ca. 2003: ``But it still sucks!''
    </para>
  </abstract>
</bookinfo>

<chapter> <!--{{{-->
  <title>Introduction  </title>
  
  <sect1>
    <title>Overview  </title>
    
    <para>
      <emphasis role="bold">Mutt-ng</emphasis> is a small but very
      powerful text-based MIME mail client.  Mutt-ng is highly
      configurable, and is well suited to the mail power user with
      advanced features like key bindings, keyboard macros, mail
      threading, regular expression searches and a powerful pattern
      matching language for selecting groups of messages.
    </para>
    
    <para>
      This documentation additionally contains documentation to
      <emphasis role="bold"> Mutt-NG </emphasis> ,a fork from Mutt
      with the goal to fix all the little annoyances of Mutt, to
      integrate all the Mutt patches that are floating around in the
      web, and to add other new features. Features specific to Mutt-ng
      will be discussed in an extra section. Don't be confused when
      most of the documentation talk about Mutt and not Mutt-ng,
      Mutt-ng contains all Mutt features, plus many more.
    </para>
    
    <para>
      
    </para>
    
  </sect1>
  
  <sect1>
    <title>Mutt-ng Home Page  </title>
    
    <para>
      <ulink url="http://www.muttng.org/">http://www.muttng.org</ulink>
    </para>
    
    <para>
      
    </para>
    
  </sect1>
  
  <sect1>
    <title>Mailing Lists  </title>
    
    <para>
      
      <itemizedlist>
        <listitem>
          
          <para>
            <email>mutt-ng-users@lists.berlios.de</email>: This is
            where the mutt-ng user support happens.
          </para>
        </listitem>
        <listitem>
          
          <para>
            <email>mutt-ng-devel@lists.berlios.de</email>: The
            development mailing list for mutt-ng
          </para>
        </listitem>
        
      </itemizedlist>
      
    </para>
    
    <para>
      
    </para>
    
  </sect1>
  
  <sect1>
    <title>Software Distribution Sites  </title>
    
    <para>
      So far, there are no official releases of Mutt-ng, but you can
      download daily snapshots from <ulink
        url="http://mutt-ng.berlios.de/snapshots/"
        >http://mutt-ng.berlios.de/snapshots/</ulink>
    </para>
    
    <para>
      
    </para>
    
  </sect1>
  
  <sect1>
    <title>IRC  </title>
    
    <para>
      Visit channel <emphasis>#muttng</emphasis> on <ulink
        url="http://www.freenode.net/">irc.freenode.net
        (www.freenode.net) </ulink> to chat with other people
      interested in Mutt-ng.  
    </para>
    
  </sect1>
  
  <sect1>
    <title>Weblog  </title>
    
    <para>
      If you want to read fresh news about the latest development in
      Mutt-ng, and get informed about stuff like interesting,
      Mutt-ng-related articles and packages for your favorite
      distribution, you can read and/or subscribe to our <ulink
        url="http://mutt-ng.supersized.org/">Mutt-ng development
        weblog</ulink>.
    </para>
    
  </sect1>
  
  <sect1>
    <title>Copyright  </title>
    
    <para>
      Mutt is Copyright (C) 1996-2000 Michael R. Elkins
      &lt;me@cs.hmc.edu&gt; and others
    </para>
    
    <para>
      This program is free software; you can redistribute it and/or modify
      it under the terms of the GNU General Public License as published by
      the Free Software Foundation; either version 2 of the License, or
      (at your option) any later version.
    </para>
    
    <para>
      This program is distributed in the hope that it will be useful,
      but WITHOUT ANY WARRANTY; without even the implied warranty of
      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      GNU General Public License for more details.
    </para>
    
    <para>
      You should have received a copy of the GNU General Public License
      along with this program; if not, write to the Free Software
      Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
    </para>
    
  </sect1>
  
</chapter>
  <!--}}}-->

<chapter>
  <title>Getting Started    </title>
  
  <sect1> <!--{{{-->
    <title>Basic Concepts      </title>
    
    <sect2> <!--{{{-->
      <title>Screens and Menus        </title>
      
      <para>
        mutt-ng offers different screens of which every has its special
        purpose:
      </para>
      
      <para>
        
        <itemizedlist>
          <listitem>
            
            <para>
              The <emphasis>index</emphasis> displays the contents of the
              currently opened
              mailbox.
              
            </para>
          </listitem>
          <listitem>
            
            <para>
              The <emphasis>pager</emphasis> is responsible for displaying
              messages, that
              is, the header, the body and all attached parts.
              
            </para>
          </listitem>
          <listitem>
            
            <para>
              The <emphasis>file browser</emphasis> offers operations on and
              displays
              information of all folders mutt-ng should watch for mail.
              
            </para>
          </listitem>
          <listitem>
            
            <para>
              The <emphasis>sidebar</emphasis> offers a permanent view of
              which mailboxes
              contain how many total, new and/or flagged mails.
              
            </para>
          </listitem>
          <listitem>
            
            <para>
              The <emphasis>help screen</emphasis> lists for all currently
              available
              commands how to invoke them as well as a short description.
              
            </para>
          </listitem>
          <listitem>
            
            <para>
              The <emphasis>compose</emphasis> menu is a comfortable
              interface take last
              actions before sending mail: change subjects, attach files,
              remove
              attachements, etc.
              
            </para>
          </listitem>
          <listitem>
            
            <para>
              The <emphasis>attachement</emphasis> menu gives a summary and
              the tree
              structure of the attachements of the current message.
              
            </para>
          </listitem>
          <listitem>
            
            <para>
              The <emphasis>alias</emphasis> menu lists all or a fraction of
              the aliases
              a user has defined.
              
            </para>
          </listitem>
          <listitem>
            
            <para>
              The <emphasis>key</emphasis> menu used in connection with
              encryption lets
              users choose the right key to encrypt with.
              
            </para>
          </listitem>
          
        </itemizedlist>
        
      </para>
      
      <para>
        When mutt-ng is started without any further options, it'll open
        the users default mailbox and display the index.
      </para>
      
      <para>
        
      </para>
      
    </sect2>
      <!--}}}-->
    
    <sect2> <!--{{{-->
      <title>Configuration        </title>
      
      <para>
        Mutt-ng does <emphasis>not</emphasis> feature an internal
        configuration
        interface or menu due to the simple fact that this would be too
        complex to handle (currently there are several <emphasis>hundred</emphasis>
        variables which fine-tune the behaviour.)
      </para>
      
      <para>
        Mutt-ng is configured using configuration files which allow
        users to add comments or manage them via version control systems
        to ease maintenance.
      </para>
      
      <para>
        Also, mutt-ng comes with a shell script named <literal>grml-muttng</literal>
        kindly contributed by users which really helps and eases the
        creation of a user's configuration file. When downloading the
        source code via a snapshot or via subversion, it can be found in
        the <literal>contrib</literal> directory.
      </para>
      
      <para>
        
      </para>
      
    </sect2>
      <!--}}}-->
    
    <sect2> <!--{{{-->
      <title>Functions        </title>
      
      <para>
        Mutt-ng offers great flexibility due to the use of functions:
        internally, every action a user can make mutt-ng perform is named
        ``function.'' Those functions are assigned to keys (or even key
        sequences) and may be completely adjusted to user's needs. The
        basic idea is that the impatient users get a very intuitive
        interface to start off with and advanced users virtually get no
        limits to adjustments.
      </para>
      
      <para>
        
      </para>
      
    </sect2>
      <!--}}}-->
    
    <sect2> <!--{{{-->
      <title>Interaction        </title>
      
      <para>
        Mutt-ng has two basic concepts of user interaction:
      </para>
      
      <para>
        
        <orderedlist>
          <listitem>
            
            <para>
              There is one dedicated line on the screen used to query
              the user for input, issue any command, query variables and
              display error and informational messages. As for every type of
              user input, this requires manual action leading to the need of
              input.
              
            </para>
          </listitem>
          <listitem>
            
            <para>
              The automatized interface for interaction are the so
              called <emphasis>hooks</emphasis>. Hooks specify actions the
              user wants to be
              performed at well-defined situations: what to do when entering
              which folder, what to do when displaying or replying to what
              kind of message, etc. These are optional, i.e. a user doesn't
              need to specify them but can do so.
              
            </para>
          </listitem>
          
        </orderedlist>
        
      </para>
      
      <para>
        
      </para>
      
    </sect2>
      <!--}}}-->
    
    <sect2> <!--{{{-->
      <title>Modularization        </title>
      
      <para>
        Although mutt-ng has many functionality built-in, many
        features can be delegated to external tools to increase
        flexibility: users can define programs to filter a message through
        before displaying, users can use any program they want for
        displaying a message, message types (such as PDF or PostScript)
        for which mutt-ng doesn't have a built-in filter can be rendered
        by arbitrary tools and so forth. Although mutt-ng has an alias
        mechanism built-in, it features using external tools to query for
        nearly every type of addresses from sources like LDAP, databases
        or just the list of locally known users.
      </para>
      
      <para>
        
      </para>
      
    </sect2>
      <!--}}}-->
    
    <sect2> <!--{{{-->
      <title>Patterns        </title>
      
      <para>
        Mutt-ng has a built-in pattern matching ``language'' which is
        as widely used as possible to present a consistent interface to
        users. The same ``pattern terms'' can be used for searching,
        scoring, message selection and much more.
      </para>
      
      <para>
        
      </para>
      
      <para>
        
      </para>
      
    </sect2>
      <!--}}}-->
    
  </sect1>
  
  <!--}}}-->
  
  <sect1> <!--{{{-->
    <title>Screens and Menus      </title>
    
    <sect2>
      <title>Index       </title>
      
      <para>
        The index is the screen that you usually see first when you
        start mutt-ng. It gives an overview over your emails in the
        currently opened mailbox. By default, this is your system mailbox.
        The information you see in the index is a list of emails, each with
        its number on the left, its flags (new email, important email,
        email that has been forwarded or replied to, tagged email, ...),
        the date when email was sent, its sender, the email size, and the
        subject. Additionally, the index also shows thread hierarchies:
        when you reply to an email, and the other person replies back, you
        can see the other's person email in a "sub-tree" below.  This is
        especially useful for personal email between a group of people or
        when you've subscribed to mailing lists.
      </para>
      
      <para>
        
      </para>
      
    </sect2>
    
    <sect2>
      <title>Pager       </title>
      
      <para>
        The pager is responsible for showing the email content. On the
        top of the pager you have an overview over the most important email
        headers like the sender, the recipient, the subject, and much more
        information. How much information you actually see depends on your
        configuration, which we'll describe below.
      </para>
      
      <para>
        Below the headers, you see the email body which usually contains
        the message. If the email contains any attachments, you will see
        more information about them below the email body, or, if the
        attachments are text files, you can view them directly in the
        pager.
      </para>
      
      <para>
        To give the user a good overview, it is possible to configure
        mutt-ng to show different things in the pager with different
        colors. Virtually everything that can be described with a regular
        expression can be colored, e.g. URLs, email addresses or smileys.
      </para>
      
      <para>
        
      </para>
      
    </sect2>
    
    <sect2>
      <title>File Browser        </title>
      
      <para>
        The file browser is the interface to the local or remote
        file system. When selecting a mailbox to open, the browser allows
        custom sorting of items, limiting the items shown by a regular
        expression and a freely adjustable format of what to display in
        which way. It also allows for easy navigation through the
        file system when selecting file(s) to attach to a message, select
        multiple files to attach and many more.
      </para>
      
      <para>
        
      </para>
      
    </sect2>
    
    <sect2>
      <title>Sidebar        </title>
      
      <para>
        The sidebar comes in handy to manage mails which are spread
        over different folders. All folders users setup mutt-ng to watch
        for new mail will be listed. The listing includes not only the
        name but also the number of total messages, the number of new and
        flagged messages. Items with new mail may be colored different
        from those with flagged mail, items may be shortened or compress
        if they're they to long to be printed in full form so that by
        abbreviated names, user still now what the name stands for.
      </para>
      
      <para>
        
      </para>
      
    </sect2>
    
    <sect2>
      <title>Help        </title>
      
      <para>
        The help screen is meant to offer a quick help to the user. It
        lists the current configuration of key bindings and their
        associated commands including a short description, and currently
        unbound functions that still need to be associated with a key
        binding (or alternatively, they can be called via the mutt-ng
        command prompt).
      </para>
      
      <para>
        
      </para>
      
    </sect2>
    
    <sect2>
      <title>Compose Menu          </title>
      
      <para>
        The compose menu features a split screen containing the
        information which really matter before actually sending a
        message by mail or posting an article to a newsgroup: who gets
        the message as what (recipient, newsgroup, who gets what kind of
        copy). Additionally, users may set security options like
        deciding whether to sign, encrypt or sign and encrypt a message
        with/for what keys.
      </para>
      
      <para>
        Also, it's used to attach messages, news articles or files to
        a message, to re-edit any attachment including the message
        itself.
      </para>
      
      <para>
        
      </para>
      
    </sect2>
    
    <sect2>
      <title>Alias Menu          </title>
      
      <para>
        The alias menu is used to help users finding the recipients
        of messages. For users who need to contact many people, there's
        no need to remember addresses or names completely because it
        allows for searching, too. The alias mechanism and thus the
        alias menu also features grouping several addresses by a shorter
        nickname, the actual alias, so that users don't have to select
        each single recipient manually.
      </para>
      
      <para>
        
      </para>
      
    </sect2>
    
    <sect2>
      <title>Attachment Menu          </title>
      
      <para>
        As will be later discussed in detail, mutt-ng features a good
        and stable MIME implementation, that is, is greatly supports
        sending and receiving messages of arbitrary type. The
        attachment menu displays a message's structure in detail: what
        content parts are attached to which parent part (which gives a
        true tree structure), which type is of what type and what size.
        Single parts may saved, deleted or modified to offer great and
        easy access to message's internals.
      </para>
      
      <para>
        
      </para>
      
    </sect2>
    
    <sect2>
      <title>Key Menu          </title>
      
      <para>
        <literal>FIXME</literal>
      </para>
      
      <para>
        
      </para>
      
      <para>
        
      </para>
      
    </sect2>
    
  </sect1>
    <!--}}}-->
  
  <sect1> <!--{{{-->
    <title>Moving Around in Menus  </title>
    
    <para>
      Information is presented in menus, very similar to ELM.  Here is a
      tableshowing the common keys used to navigate menus in Mutt-ng.
    </para>
    
    <para>

      <table>
        <title>Default Menu Movement Keys</title>
        <tgroup cols="3" align="left" colsep="1" rowsep="1">
        <thead>
          <row>
            <entry>Key</entry>
            <entry>Function</entry>
            <entry>Description</entry>
          </row>
        </thead>
        <tbody>
          <row>
            <entry><code>j</code> or <code>Down</code></entry>
            <entry><code>next-entry</code></entry>
            <entry>move to the next entry</entry>
          </row>
          <row>
            <entry><code>k</code> or <code>Up</code></entry>
            <entry><code>previous-entry</code></entry>
            <entry>move to the previous entry</entry>
          </row>
          <row>
            <entry><code>z</code> or <code>PageDn</code></entry>
            <entry><code>page-down</code></entry>
            <entry>go to the next page</entry>
          </row>
          <row>
            <entry><code>Z</code> or <code>PageUp</code></entry>
            <entry><code>page-up</code></entry>
            <entry>go to the previous page</entry>
          </row>
          <row>
            <entry><code>=</code> or <code>Home</code></entry>
            <entry><code>first-entry</code></entry>
            <entry>jump to the first entry</entry>
          </row>
          <row>
            <entry><code>*</code> or <code>End</code></entry>
            <entry><code>last-entry</code></entry>
            <entry>jump to the last entry</entry>
          </row>
          <row>
            <entry><code>q</code></entry>
            <entry><code>quit</code></entry>
            <entry>exit the current menu</entry>
          </row>
          <row>
            <entry><code>?</code></entry>
            <entry><code>help</code></entry>
            <entry>list all key bindings for the current menu</entry>
          </row>
        </tbody>
      </tgroup>
    </table>


    </para>
    
    <para>
      
    </para>
    
  </sect1>
    <!--}}}-->
  
  <sect1 id="editing"> <!--{{{-->
    <title>Editing Input Fields  </title>
    
    <para>
      Mutt-ng has a builtin line editor which is used as the primary way to
      input
      textual data such as email addresses or filenames.  The keys used to
      move
      around while editing are very similar to those of Emacs.
    </para>
    
    <para>

      <table>
        <title>Built-In Editor Functions</title>
        <tgroup cols="3" align="left" colsep="1" rowsep="1">
        <thead>
          <row>
            <entry>Key</entry>
            <entry>Function</entry>
            <entry>Description</entry>
          </row>
        </thead>
        <tbody>
          <row>
            <entry><code>^A or &#60;Home&#62;  </code></entry>
            <entry><code>bol     </code></entry>
            <entry>move to the start of the line</entry>
          </row>
          <row>
            <entry><code>^B or &#60;Left&#62;   </code></entry>
            <entry><code>backward-char </code>
            </entry><entry>move back one char</entry>
          </row>
          <row>
            <entry><code>Esc B  </code></entry>
            <entry><code>backward-word    </code></entry>
            <entry>move back one word</entry>
          </row>
          <row>
            <entry><code>^D or &#60;Delete&#62;  </code></entry>
            <entry><code>delete-char    </code></entry>
            <entry>delete the char under the cursor</entry>
          </row>
          <row>
            <entry><code>^E or &#60;End&#62;   </code></entry>
            <entry><code>eol          </code></entry>
            <entry>move to the end of the line</entry>
          </row>
          <row>
            <entry><code>^F or &#60;Right&#62;  </code></entry>
            <entry><code>forward-char   </code></entry>
            <entry>move forward one char</entry>
          </row>
          <row>
            <entry><code>Esc F </code></entry>
            <entry><code>forward-word      </code></entry>
            <entry>move forward one word</entry>
          </row>
          <row>
            <entry><code>&#60;Tab&#62;   </code></entry>
            <entry><code>complete     </code></entry>
            <entry>complete filename or alias</entry>
          </row>
          <row>
            <entry><code>^T         </code></entry>
            <entry><code>complete-query   </code></entry>
            <entry>complete address with query</entry>
          </row>
          <row>
            <entry><code>^K          </code></entry>
            <entry><code>kill-eol      </code></entry>
            <entry>delete to the end of the line</entry>
          </row>
          <row>
            <entry><code>ESC d </code></entry>
            <entry><code>kill-eow    </code></entry>
            <entry>delete to the end of the word</entry>
          </row>
          <row>
            <entry><code>^W     </code></entry>
            <entry><code>kill-word     </code></entry>
            <entry>kill the word in front of the cursor</entry>
          </row>
          <row>
            <entry><code>^U      </code></entry>
            <entry><code>kill-line      </code></entry>
            <entry>delete entire line</entry>
          </row>
          <row>
            <entry><code>^V       </code></entry>
            <entry><code>quote-char    </code></entry>
            <entry>quote the next typed key</entry>
          </row>
          <row>
            <entry><code>&#60;Up&#62;   </code></entry>
            <entry><code>history-up   </code></entry>
            <entry>recall previous string from history</entry>
          </row>
          <row>
            <entry><code>&#60;Down&#62;      </code></entry>
            <entry><code>history-down   </code></entry>
            <entry>recall next string from history</entry>
          </row>
          <row>
            <entry><code>&#60;BackSpace&#62;  </code></entry>
            <entry><code>backspace     </code></entry>
            <entry>kill the char in front of the cursor</entry>
          </row>
          <row>
            <entry><code>Esc u        </code></entry>
            <entry><code>upcase-word      </code></entry>
            <entry>convert word to upper case</entry>
          </row>
          <row>
            <entry><code>Esc l        </code></entry>
            <entry><code>downcase-word      </code></entry>
            <entry>convert word to lower case</entry>
          </row>
          <row>
            <entry><code>Esc c        </code></entry>
            <entry><code>capitalize-word    </code></entry>
            <entry>capitalize the word</entry>
          </row>
          <row>
            <entry><code>^G           </code></entry>
            <entry><code>n/a    </code></entry>
            <entry>abort</entry>
          </row>
          <row>
            <entry><code>&#60;Return&#62;     </code></entry>
            <entry><code>n/a    </code></entry>
            <entry>finish editing</entry>
          </row>
        </tbody>
      </tgroup>
    </table>

    </para>
    
    <para>
      You can remap the <emphasis>editor</emphasis> functions using the <link linkend="bind">
        bind
      </link>
      command.  For example, to make the <emphasis>Delete</emphasis> key
      delete the character in
      front of the cursor rather than under, you could use
    </para>
    
    <para>
      <literal>bind editor &lt;delete&gt; backspace</literal>
    </para>
    
    <para>
      
    </para>
    
  </sect1>
    <!--}}}-->
  
  <sect1>
    <title>Reading Mail - The Index and Pager  </title> <!--{{{-->
    
    <para>
      Similar to many other mail clients, there are two modes in which mail
      isread in Mutt-ng.  The first is the index of messages in the mailbox,
      which is
      called the ``index'' in Mutt-ng.  The second mode is the display of the
      message contents.  This is called the ``pager.''
    </para>
    
    <para>
      The next few sections describe the functions provided in each of these
      modes.
    </para>
    
    <sect2>
      <title>The Message Index</title> <!--{{{-->
      
      <para>

      <table>
        <title>Default Index Menu Bindings</title>
        <tgroup cols="3" align="left" colsep="1" rowsep="1">
        <thead>
          <row>
            <entry>Key</entry>
            <entry>Function</entry>
            <entry>Description</entry>
          </row>
        </thead>
        <tbody>
          <row><entry><code>c      </code></entry><entry><code></code></entry><entry>change to a different mailbox</entry></row>
          <row><entry><code>ESC c    </code></entry><entry><code></code></entry><entry>change to a folder in read-only mode</entry></row>
          <row><entry><code>C        </code></entry><entry><code></code></entry><entry>copy the current message to another mailbox</entry></row>
          <row><entry><code>ESC C     </code></entry><entry><code></code></entry><entry>decode a message and copy it to a folder</entry></row>
          <row><entry><code>ESC s    </code></entry><entry><code></code></entry><entry>decode a message and save it to a folder</entry></row>
          <row><entry><code>D       </code></entry><entry><code></code></entry><entry>delete messages matching a pattern</entry></row>
          <row><entry><code>d     </code></entry><entry><code></code></entry><entry>delete the current message</entry></row>
          <row><entry><code>F      </code></entry><entry><code></code></entry><entry>mark as important</entry></row>
          <row><entry><code>l      </code></entry><entry><code></code></entry><entry>show messages matching a pattern</entry></row>
          <row><entry><code>N       </code></entry><entry><code></code></entry><entry>mark message as new</entry></row>
          <row><entry><code>o       </code></entry><entry><code></code></entry><entry>change the current sort method</entry></row>
          <row><entry><code>O       </code></entry><entry><code></code></entry><entry>reverse sort the mailbox</entry></row>
          <row><entry><code>q       </code></entry><entry><code></code></entry><entry>save changes and exit</entry></row>
          <row><entry><code>s        </code></entry><entry><code></code></entry><entry>save-message</entry></row>
          <row><entry><code>T       </code></entry><entry><code></code></entry><entry>tag messages matching a pattern</entry></row>
          <row><entry><code>t       </code></entry><entry><code></code></entry><entry>toggle the tag on a message</entry></row>
          <row><entry><code>ESC t  </code></entry><entry><code></code></entry><entry>toggle tag on entire message thread</entry></row>
          <row><entry><code>U       </code></entry><entry><code></code></entry><entry>undelete messages matching a pattern</entry></row>
          <row><entry><code>u        </code></entry><entry><code></code></entry><entry>undelete-message</entry></row>
          <row><entry><code>v        </code></entry><entry><code></code></entry><entry>view-attachments</entry></row>
          <row><entry><code>x       </code></entry><entry><code></code></entry><entry>abort changes and exit</entry></row>
          <row><entry><code>&#60;Return&#62;  </code></entry><entry><code></code></entry><entry>display-message</entry></row>
          <row><entry><code>&#60;Tab&#62;      </code></entry><entry><code></code></entry><entry>jump to the next new message</entry></row>
          <row><entry><code>@      </code></entry><entry><code></code></entry><entry>show the author's full e-mail address</entry></row>
          <row><entry><code>$       </code></entry><entry><code></code></entry><entry>save changes to mailbox</entry></row>
          <row><entry><code>/       </code></entry><entry><code></code></entry><entry>search</entry></row>
          <row><entry><code>ESC /     </code></entry><entry><code></code></entry><entry>search-reverse</entry></row>
          <row><entry><code>^L       </code></entry><entry><code></code></entry><entry>clear and redraw the screen</entry></row>
          <row><entry><code>^T        </code></entry><entry><code></code></entry><entry>untag messages matching a pattern</entry></row>
        </tbody>
      </tgroup>
    </table>

      </para>
      
      <sect3>
        <title>Status Flags</title> <!--{{{-->
        
        <para>
          In addition to who sent the message and the subject, a short
          summary of
          the disposition of each message is printed beside the message
          number.
          Zero or more of the following ``flags'' may appear, which mean:
        </para>
        
        <para>

          <variablelist>
            
            <varlistentry>
              <term>D</term>
              <listitem>
                <para>
                  message is deleted (is marked for deletion)
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>d</term>
              <listitem>
                <para>
                  message have attachments marked for deletion
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>K</term>
              <listitem>
                <para>
                  contains a PGP public key
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>N</term>
              <listitem>
                <para>
                  message is new
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>O</term>
              <listitem>
                <para>
                  message is old
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>P</term>
              <listitem>
                <para>
                  message is PGP encrypted
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>r</term>
              <listitem>
                <para>
                  message has been replied to
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>S</term>
              <listitem>
                <para>
                  message is signed, and the signature is succesfully
                  verified
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>s</term>
              <listitem>
                <para>
                  message is signed
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>!</term>
              <listitem>
                <para>
                  message is flagged
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>*</term>
              <listitem>
                <para>
                  message is tagged
                </para>
              </listitem>
            </varlistentry>
          </variablelist>
        </para>
        
        <para>
          Some of the status flags can be turned on or off using
          
          <itemizedlist>
            <listitem>
              
              <para>
                <emphasis role="bold">set-flag</emphasis> (default: w)
              </para>
            </listitem>
            <listitem>
              
              <para>
                <emphasis role="bold">clear-flag</emphasis> (default: W)
              </para>
            </listitem>
            
          </itemizedlist>
          
        </para>
        
        <para>
          Furthermore, the following flags reflect who the message is
          addressed
          to.  They can be customized with the
          <link linkend="to-chars">&dollar;to&lowbar;chars</link> variable.
        </para>
        
        <para>
          <variablelist>
            
            <varlistentry>
              <term>+</term>
              <listitem>
                <para>
                  message is to you and you only
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>T</term>
              <listitem>
                <para>
                  message is to you, but also to or cc'ed to others
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>C</term>
              <listitem>
                <para>
                  message is cc'ed to you
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>F</term>
              <listitem>
                <para>
                  message is from you
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>L</term>
              <listitem>
                <para>
                  message is sent to a subscribed mailing list
                </para>
              </listitem>
            </varlistentry>
          </variablelist>
        </para>
        
        <!--}}}-->
      </sect3>
      
      <!--}}}-->
    </sect2>
    
    <sect2>
      <title>The Pager</title> <!--{{{-->
      
      <para>
        By default, Mutt-ng uses its builtin pager to display the body of
        messages.
        The pager is very similar to the Unix program <emphasis>less</emphasis> though not nearly as
        featureful.
      </para>
      
      <para>

      <table>
        <title>Default Pager Menu Bindings</title>
        <tgroup cols="3" align="left" colsep="1" rowsep="1">
        <thead>
          <row>
            <entry>Key</entry>
            <entry>Function</entry>
            <entry>Description</entry>
          </row>
        </thead>
        <tbody>
          <row><entry><code>&#60;Return&#62;   </code></entry><entry><code></code></entry><entry>go down one line</entry></row>
          <row><entry><code>&#60;Space&#62;   </code></entry><entry><code></code></entry><entry>display the next page (or next message if at the end of a message)</entry></row>
          <row><entry><code>-           </code></entry><entry><code></code></entry><entry>go back to the previous page</entry></row>
          <row><entry><code>n            </code></entry><entry><code></code></entry><entry>search for next match</entry></row>
          <row><entry><code>S         </code></entry><entry><code></code></entry><entry>skip beyond quoted text</entry></row>
          <row><entry><code>T         </code></entry><entry><code></code></entry><entry>toggle display of quoted text</entry></row>
          <row><entry><code>?        </code></entry><entry><code></code></entry><entry>show key bindings</entry></row>
          <row><entry><code>/        </code></entry><entry><code></code></entry><entry>search for a regular expression (pattern)</entry></row>
          <row><entry><code>ESC /   </code></entry><entry><code></code></entry><entry>search backwards for a regular expression</entry></row>
          <row><entry><code>\       </code></entry><entry><code></code></entry><entry>toggle search pattern coloring</entry></row>
          <row><entry><code>^      </code></entry><entry><code></code></entry><entry>jump to the top of the message</entry></row>
        </tbody>
      </tgroup>
    </table>


      </para>
      
      <para>
        In addition, many of the functions from the <emphasis>index</emphasis> are available in
        the pager, such as <emphasis>delete-message</emphasis> or <emphasis>
          copy-message
        </emphasis>
        (this is one
        advantage over using an external pager to view messages).
      </para>
      
      <para>
        Also, the internal pager supports a couple other advanced features.
        For
        one, it will accept and translate the ``standard'' nroff sequences
        forbold and underline. These sequences are a series of either the
        letter,
        backspace (&circ;H), the letter again for bold or the letter,
        backspace,
        ``&lowbar;'' for denoting underline. Mutt-ng will attempt to display
        these
        in bold and underline respectively if your terminal supports them. If
        not, you can use the bold and underline <link
linkend="color">color</link>
        objects to specify a color or mono attribute for them.
      </para>
      
      <para>
        Additionally, the internal pager supports the ANSI escape
        sequences for character attributes.  Mutt-ng translates them
        into the correct color and character settings.  The sequences
        Mutt-ng supports are: <literal>ESC [ Ps;Ps;Ps;...;Ps
          m</literal> (see table below for possible values for
        <code>Ps</code>).
      </para>
      
      <para>

      <table>
        <title>ANSI Escape Sequences</title>
        <tgroup cols="2" align="left" colsep="1" rowsep="1">
        <thead>
          <row>
            <entry>Value</entry>
            <entry>Attribute</entry>
          </row>
        </thead>
        <tbody>
          <row><entry><code>0  </code></entry><entry>All Attributes Off</entry></row>
          <row><entry><code>1  </code></entry><entry>Bold on</entry></row>
          <row><entry><code>4  </code></entry><entry>Underline on</entry></row>
          <row><entry><code>5  </code></entry><entry>Blink on</entry></row>
          <row><entry><code>7 </code></entry><entry>Reverse video on</entry></row>
          <row><entry><code>3x  </code></entry><entry>Foreground color is x (see table below)</entry></row>
          <row><entry><code>4x </code></entry><entry>Background color is x (see table below)</entry></row>
        </tbody>
      </tgroup>
    </table>

    
      <table>
        <title>ANSI Colors</title>
        <tgroup cols="2" align="left" colsep="1" rowsep="1">
        <thead>
          <row>
            <entry>Number</entry>
            <entry>Color</entry>
          </row>
        </thead>
        <tbody>
          <row><entry><code>0   </code></entry><entry>black</entry></row>
          <row><entry><code>1  </code></entry><entry>red</entry></row>
          <row><entry><code>2  </code></entry><entry>green</entry></row>
          <row><entry><code>3  </code></entry><entry>yellow</entry></row>
          <row><entry><code>4  </code></entry><entry>blue</entry></row>
          <row><entry><code>5 </code></entry><entry>magenta</entry></row>
          <row><entry><code>6  </code></entry><entry>cyan</entry></row>
          <row><entry><code>7 </code></entry><entry>white</entry></row>
        </tbody>
      </tgroup>
    </table>


        </para>
        
        <para>
          Mutt-ng uses these attributes for handling text/enriched messages,
          and they
          can also be used by an external <link
  linkend="auto-view">autoview</link>
          script for highlighting purposes.  <emphasis role="bold">Note:</emphasis> If you change the colors for your
          display, for example by changing the color associated with color2 for
          your xterm, then that color will be used instead of green.
        </para>
        
        <!--}}}-->
      </sect2>
      
      <sect2 id="threads">
        <title>Threaded Mode</title> <!--{{{-->
        
        <para>
          When the mailbox is <link linkend="sort">sorted</link> by <emphasis>
            threads
          </emphasis>
          ,there are
          a few additional functions available in the <emphasis>index</emphasis> and <emphasis>
            pager
          </emphasis>
          modes.
        </para>
        
        <para>

        <table>
          <title>Default Thread Function Bindings</title>
          <tgroup cols="3" align="left" colsep="1" rowsep="1">
          <thead>
            <row>
              <entry>Key</entry>
              <entry>Function</entry>
              <entry>Description</entry>
            </row>
          </thead>
          <tbody>
            <row><entry><code>^D   </code></entry><entry><code>delete-thread       </code></entry><entry>delete all messages in the current  thread</entry></row>
            <row><entry><code>^U   </code></entry><entry><code>undelete-thread     </code></entry><entry>undelete all messages in the current thread</entry></row>
            <row><entry><code>^N   </code></entry><entry><code>next-thread         </code></entry><entry>jump to the start of the next thread</entry></row>
            <row><entry><code>^P   </code></entry><entry><code>previous-thread     </code></entry><entry>jump to the start of the previous thread</entry></row>
            <row><entry><code>^R    </code></entry><entry><code>read-thread         </code></entry><entry>mark the current thread as read</entry></row>
            <row><entry><code>ESC d </code></entry><entry><code>delete-subthread    </code></entry><entry>delete all messages in the current subthread</entry></row>
            <row><entry><code>ESC u </code></entry><entry><code>undelete-subthread  </code></entry><entry>undelete all messages in the current subthread</entry></row>
            <row><entry><code>ESC n </code></entry><entry><code>next-subthread      </code></entry><entry>jump to the start of the next subthread</entry></row>
            <row><entry><code>ESC p </code></entry><entry><code>previous-subthread  </code></entry><entry>jump to the start of the previous subthread</entry></row>
            <row><entry><code>ESC r </code></entry><entry><code>read-subthread      </code></entry><entry>mark the current subthread as read </entry></row>
            <row><entry><code>ESC t </code></entry><entry><code>tag-thread          </code></entry><entry>toggle the tag on the current thread</entry></row>
            <row><entry><code>ESC v </code></entry><entry><code>collapse-thread    </code></entry><entry>toggle collapse for the current thread</entry></row>
            <row><entry><code>ESC V </code></entry><entry><code>collapse-all      </code></entry><entry>toggle collapse for all threads</entry></row>
            <row><entry><code>P    </code></entry><entry><code>parent-message        </code></entry><entry>jump to parent message in thread</entry></row>
          </tbody>
        </tgroup>
      </table>

          
        </para>
        
        <para>
          <emphasis role="bold">Note:</emphasis> Collapsing a thread displays
          only the first message
          in the thread and hides the others. This is useful when threads
          contain so many messages that you can only see a handful of threads
          onthe screen. See &percnt;M in <link
  linkend="index-format">
            index-format
          </link>
          .
          For example, you could use
          "&percnt;?M?(&num;&percnt;03M)&amp;(&percnt;4l)?" in <link linkend="index-format">
            index-format
          </link>
          to optionally
          display the number of hidden messages if the thread is collapsed.
        </para>
        
        <para>
          See also: <link linkend="strict-threads">strict-threads</link>.
        </para>
        
        <!--}}}-->
      </sect2>
      
      <sect2>
        <title>Miscellaneous Functions</title> <!--{{{-->
        
        <para>
          <emphasis role="bold">create-alias</emphasis><anchor id="create-alias"/>
           (default: a)
          
        </para>
        
        <para>
          Creates a new alias based upon the current message (or prompts for a
          new one).  Once editing is complete, an <link linkend="alias">alias</link>
          command is added to the file specified by the <link linkend="alias-file">
            alias-file
          </link>
          variable for future use. <emphasis role="bold">Note:</emphasis>
          Specifying an <link linkend="alias-file">alias-file</link>
          does not add the aliases specified there-in, you must also <link linkend="source">
            source
          </link>
          the file.
        </para>
        
        <para>
          <emphasis role="bold">check-traditional-pgp</emphasis><anchor id="check-traditional-pgp"/>
           (default: ESC P)
          
        </para>
        
        <para>
          This function will search the current message for content signed or
          encrypted with PGP the "traditional" way, that is, without proper
          MIME tagging.  Technically, this function will temporarily change
          the MIME content types of the body parts containing PGP data; this
          is similar to the <link linkend="edit-type">edit-type</link>
          function's
          effect.
        </para>
        
        <para>
          <emphasis role="bold">display-toggle-weed</emphasis><anchor id="display-toggle-weed"/>
           (default: h)
          
        </para>
        
        <para>
          Toggles the weeding of message header fields specified by <link linkend="ignore">
            ignore
          </link>
          commands.
        </para>
        
        <para>
          <emphasis role="bold">edit</emphasis><anchor id="edit"/>
           (default: e)
          
        </para>
        
        <para>
          This command (available in the ``index'' and ``pager'') allows you to
          edit the raw current message as it's present in the mail folder.
          After you have finished editing, the changed message will be
          appended to the current folder, and the original message will be
          marked for deletion.
        </para>
        
        <para>
          <emphasis role="bold">edit-type</emphasis><anchor id="edit-type"/>
          
          (default: &circ;E on the attachment menu, and in the pager and index
          menus; &circ;T on the
          compose menu)
        </para>
        
        <para>
          This command is used to temporarily edit an attachment's content
          type to fix, for instance, bogus character set parameters.  When
          invoked from the index or from the pager, you'll have the
          opportunity to edit the top-level attachment's content type.  On the
          <link linkend="attach-menu">attach-menu</link>, you can change any
          attachment's content type. These changes are not persistent, and get
          lost upon changing folders.
        </para>
        
        <para>
          Note that this command is also available on the <link linkend="compose-menu">
            compose-menu
          </link>
          .There, it's used to
          fine-tune the properties of attachments you are going to send.
        </para>
        
        <para>
          <emphasis role="bold">enter-command</emphasis><anchor id="enter-command"/>
           (default: ``:'')
          
        </para>
        
        <para>
          This command is used to execute any command you would normally put in
          a
          configuration file.  A common use is to check the settings of
          variables, or
          in conjunction with <link linkend="macro">macro</link> to change
          settings on the
          fly.
        </para>
        
        <para>
          <emphasis role="bold">extract-keys</emphasis><anchor id="extract-keys"/>
           (default: &circ;K)
          
        </para>
        
        <para>
          This command extracts PGP public keys from the current or tagged
          message(s) and adds them to your PGP public key ring.
        </para>
        
        <para>
          <emphasis role="bold">forget-passphrase</emphasis><anchor id="forget-passphrase"/>
           (default:
          &circ;F)
          
        </para>
        
        <para>
          This command wipes the passphrase(s) from memory. It is useful, if
          you misspelled the passphrase.
        </para>
        
        <para>
          <emphasis role="bold">list-reply</emphasis><anchor id="func-list-reply"/>
           (default: L)
          
        </para>
        
        <para>
          Reply to the current or tagged message(s) by extracting any addresses
          which
          match the regular expressions given by the <link linkend="lists">
            lists
          </link>
          commands, but also honor any <literal>Mail-Followup-To</literal>
          header(s) if the
          <link linkend="honor-followup-to">honor-followup-to</link>
          configuration variable is set.  Using this when replying to messages
          posted
          to mailing lists helps avoid duplicate copies being sent to the
          author of
          the message you are replying to.
        </para>
        
        <para>
          <emphasis role="bold">pipe-message</emphasis><anchor id="pipe-message"/>
           (default: &verbar;)
          
        </para>
        
        <para>
          Asks for an external Unix command and pipes the current or
          tagged message(s) to it.  The variables <link linkend="pipe-decode">
            pipe-decode
          </link>
          ,<link linkend="pipe-split">pipe-split</link>, <link linkend="pipe-sep">
            pipe-sep
          </link>
          and <link linkend="wait-key">wait-key</link> control the exact
          behavior of this
          function.
        </para>
        
        <para>
          <emphasis role="bold">resend-message</emphasis><anchor id="resend-message"/>
           (default: ESC e)
          
        </para>
        
        <para>
          With resend-message, mutt takes the current message as a template for
          a
          new message.  This function is best described as "recall from
          arbitrary
          folders".  It can conveniently be used to forward MIME messages while
          preserving the original mail structure. Note that the amount of
          headers
          included here depends on the value of the <link linkend="weed">weed</link>
          variable.
        </para>
        
        <para>
          This function is also available from the attachment menu. You can use
          this
          to easily resend a message which was included with a bounce message
          as a message/rfc822 body part.
        </para>
        
        <para>
          <emphasis role="bold">shell-escape</emphasis><anchor id="shell-escape"/>
           (default: !)
          
        </para>
        
        <para>
          Asks for an external Unix command and executes it.  The <link linkend="wait-key">
            wait-key
          </link>
          can be used to control
          whether Mutt-ng will wait for a key to be pressed when the command
          returns
          (presumably to let the user read the output of the command), based on
          the return status of the named command.
        </para>
        
        <para>
          <emphasis role="bold">toggle-quoted</emphasis><anchor id="toggle-quoted"/>
           (default: T)
          
        </para>
        
        <para>
          The <emphasis>pager</emphasis> uses the <link linkend="quote-regexp">
            quote-regexp
          </link>
          variable to detect quoted text when
          displaying the body of the message.  This function toggles the
          displayof the quoted material in the message.  It is particularly
          useful when
          are interested in just the response and there is a large amount of
          quoted text in the way.
        </para>
        
        <para>
          <emphasis role="bold">skip-quoted</emphasis><anchor id="skip-quoted"/>
           (default: S)
          
        </para>
        
        <para>
          This function will go to the next line of non-quoted text which come
          after a line of quoted text in the internal pager.
        </para>
        
        <para>
          
        </para>
        
        <!--}}}-->
      </sect2>
      
      <!--}}}-->
    </sect1>
    
    <sect1>
      <title>Sending Mail  </title> <!--{{{-->
      
      <para>
        The following bindings are available in the <emphasis>index</emphasis>
        for sending
        messages.
      </para>
      
      <para>

        <table>
          <title>Default Mail Composition Bindings</title>
          <tgroup cols="3" align="left" colsep="1" rowsep="1">
          <thead>
            <row>
              <entry>Key</entry>
              <entry>Function</entry>
              <entry>Description</entry>
            </row>
          </thead>
          <tbody>
            <row><entry><code>m    </code></entry><entry><code>compose    </code></entry><entry>compose a new message</entry></row>
            <row><entry><code>r     </code></entry><entry><code>reply       </code></entry><entry>reply to sender</entry></row>
            <row><entry><code>g     </code></entry><entry><code>group-reply </code></entry><entry>reply to all recipients</entry></row>
            <row><entry><code>L     </code></entry><entry><code>list-reply  </code></entry><entry>reply to mailing list address</entry></row>
            <row><entry><code>f     </code></entry><entry><code>forward     </code></entry><entry>forward message</entry></row>
            <row><entry><code>b     </code></entry><entry><code>bounce      </code></entry><entry>bounce (remail) message</entry></row>
            <row><entry><code>ESC k  </code></entry><entry><code>mail-key    </code></entry><entry>mail a PGP public key to someone</entry></row>
          </tbody>
        </tgroup>
      </table>

      </para>
      
      <para>
        Bouncing a message sends the message as is to the recipient you
        specify.  Forwarding a message allows you to add comments or
        modify the message you are forwarding.  These items are discussed
        in greater detail in the next chapter <link linkend="forwarding-mail">
          forwarding-mail
        </link>
        .
      </para>
      
      <sect2>
        <title>Composing new messages  </title> <!--{{{-->
        
        <para>
          When you want to send an email using mutt-ng, simply press <literal>m</literal> on
          your keyboard. Then, mutt-ng asks for the recipient via a prompt in
          the last line:
        </para>
        
        <para>
          
          <screen>
To:</screen>
          
        </para>
        
        <para>
          After you've finished entering the recipient(s), press return. If you
          want to send an email to more than one recipient, separate the email
          addresses using the comma "<literal>,</literal>". Mutt-ng then asks
          you for the email
          subject. Again, press return after you've entered it. After that,
          mutt-ng
          got the most important information from you, and starts up an editor
          where you can then enter your email.
        </para>
        
        <para>
          The editor that is called is selected in the following way: you
          can e.g. set it in the mutt-ng configuration:
        </para>
        
        <para>
          
          <screen>
set editor = "vim +/^$/ -c ':set tw=72'"
set editor = "nano"
set editor = "emacs"</screen>
          
        </para>
        
        <para>
          If you don't set your preferred editor in your configuration, mutt-ng
          first looks whether the environment variable <literal>$VISUAL</literal> is set, and if
          so, it takes its value as editor command. Otherwise, it has a look
          at <literal>$EDITOR</literal> and takes its value if it is set. If no
          editor command
          can be found, mutt-ng simply assumes <literal>vi</literal> to be the
          default editor,
          since it's the most widespread editor in the Unix world and it's
          pretty
          safe to assume that it is installed and available.
        </para>
        
        <para>
          When you've finished entering your message, save it and quit your 
          editor. Mutt-ng will then present you with a summary screen, the
          compose menu. 
          On the top, you see a summary of the most important available key
          commands.
          Below that, you see the sender, the recipient(s), Cc and/or Bcc 
          recipient(s), the subject, the reply-to address, and optionally
          information where the sent email will be stored and whether it should
          be digitally signed and/or encrypted.
        </para>
        
        <para>
          Below that, you see a list of "attachments". The mail you've just
          entered before is also an attachment, but due to its special type
          (it's plain text), it will be displayed as the normal message on
          the receiver's side.
        </para>
        
        <para>
          At this point, you can add more attachments, pressing <literal>a</literal>, you
          can edit the recipient addresses, pressing <literal>t</literal> for
          the "To:" field,
          <literal>c</literal> for the "Cc:" field, and <literal>b</literal>
          for the "Bcc: field. You can
          also edit the subject the subject by simply pressing <literal>s</literal> or the
          email message that you've entered before by pressing <literal>e</literal>. You will
          then again return to the editor. You can even edit the sender, by
          pressing
          <literal>&lt;esc&gt;f</literal>, but this shall only be used with
          caution.
        </para>
        
        <para>
          Alternatively, you can configure mutt-ng in a way that most of the
          above settings can be edited using the editor. Therefore, you only
          need to add the following to your configuration:
        </para>
        
        <para>
          
          <screen>
set edit_headers</screen>
          
        </para>
        
        <para>
          Once you have finished editing the body of your mail message, you are
          returned to the <emphasis>compose</emphasis> menu.  The following
          options are available:
        </para>
        
        <para>

        <table>
          <title>Default Compose Menu Bindings</title>
          <tgroup cols="3" align="left" colsep="1" rowsep="1">
          <thead>
            <row>
              <entry>Key</entry>
              <entry>Function</entry>
              <entry>Description</entry>
            </row>
          </thead>
          <tbody>
            <row><entry><code>a    </code></entry><entry><code>attach-file  </code></entry><entry>attach a file</entry></row>
            <row><entry><code>A    </code></entry><entry><code>attach-message  </code></entry><entry>attach message(s) to the message</entry></row>
            <row><entry><code>ESC k  </code></entry><entry><code>attach-key       </code></entry><entry>attach a PGP public key</entry></row>
            <row><entry><code>d    </code></entry><entry><code>edit-description  </code></entry><entry>edit description on attachment</entry></row>
            <row><entry><code>D  </code></entry><entry><code>detach-file     </code></entry><entry>detach a file</entry></row>
            <row><entry><code>t </code></entry><entry><code>edit-to         </code></entry><entry>edit the To field</entry></row>
            <row><entry><code>ESC f </code></entry><entry><code>edit-from       </code></entry><entry>edit the From field</entry></row>
            <row><entry><code>r  </code></entry><entry><code>edit-reply-to   </code></entry><entry>edit the Reply-To field</entry></row>
            <row><entry><code>c </code></entry><entry><code>edit-cc         </code></entry><entry>edit the Cc field</entry></row>
            <row><entry><code>b      </code></entry><entry><code>edit-bcc        </code></entry><entry>edit the Bcc field</entry></row>
            <row><entry><code>y     </code></entry><entry><code>send-message    </code></entry><entry>send the message</entry></row>
            <row><entry><code>s    </code></entry><entry><code>edit-subject    </code></entry><entry>edit the Subject</entry></row>
            <row><entry><code>S   </code></entry><entry><code>smime-menu        </code></entry><entry>select S/MIME options</entry></row>
            <row><entry><code>f      </code></entry><entry><code>edit-fcc        </code></entry><entry>specify an ``Fcc'' mailbox</entry></row>
            <row><entry><code>p     </code></entry><entry><code>pgp-menu        </code></entry><entry>select PGP options</entry></row>
            <row><entry><code>P    </code></entry><entry><code>postpone-message </code></entry><entry>postpone this message until later</entry></row>
            <row><entry><code>q   </code></entry><entry><code>quit            </code></entry><entry>quit (abort) sending the message</entry></row>
            <row><entry><code>w  </code></entry><entry><code>write-fcc      </code></entry><entry>write the message to a folder</entry></row>
            <row><entry><code>i </code></entry><entry><code>ispell          </code></entry><entry>check spelling (if available on your system)</entry></row>
            <row><entry><code>^F  </code></entry><entry><code>forget-passphrase   </code></entry><entry>wipe passphrase(s) from memory</entry></row>
          </tbody>
        </tgroup>
      </table>

        </para>
        
        <para>
          <emphasis role="bold">Note:</emphasis> The attach-message function
          will prompt you for a folder to
          attach messages from. You can now tag messages in that folder and
          theywill be attached to the message you are sending. Note that
          certainoperations like composing a new mail, replying, forwarding,
          etc. are
          not permitted when you are in that folder. The &percnt;r in <link linkend="status-format">
            status-format
          </link>
          will change to
          a 'A' to indicate that you are in attach-message mode.
        </para>
        
        <para>
          
        </para>
        
        <!--}}}-->
      </sect2>
      
      <sect2>
        <title>Replying      </title> <!--{{{-->
        
        <sect3>
          <title>Simple Replies       </title> <!--{{{-->
          
          <para>
            When you want to reply to an email message, select it in the index
            menu and then press <literal>r</literal>. Mutt-ng's behaviour is
            then similar to the 
            behaviour when you compose a message: first, you will be asked for
            the recipient, then for the subject, and then, mutt-ng will start
            the editor with the quote attribution and the quoted message. This
            can e.g. look like the example below.
          </para>
          
          <para>
            
            <screen>
On Mon, Mar 07, 2005 at 05:02:12PM +0100, Michael Svensson wrote:
&gt; Bill, can you please send last month's progress report to Mr. 
&gt; Morgan? We also urgently need the cost estimation for the new 
&gt; production server that we want to set up before our customer's 
&gt; project will go live.</screen>
            
          </para>
          
          <para>
            You can start editing the email message. It is strongly
            recommended to put your answer <emphasis>below</emphasis> the
            quoted text and to
            only quote what is really necessary and that you refer to. Putting
            your answer on top of the quoted message, is, although very
            widespread, very often not considered to be a polite way to answer
            emails.
          </para>
          
          <para>
            The quote attribution is configurable, by default it is set to
            
            <screen>
set attribution = "On %d, %n wrote:"</screen>
            
          </para>
          
          <para>
            It can also be set to something more compact, e.g.
            
            <screen>
set attribution = "attribution="* %n &lt;%a&gt; [%(%y-%m-%d %H:%M)]:"</screen>
            
          </para>
          
          <para>
            The example above results in the following attribution:
            
            <screen>
* Michael Svensson &lt;svensson@foobar.com&gt; [05-03-06 17:02]:
&gt; Bill, can you please send last month's progress report to Mr. 
&gt; Morgan? We also urgently need the cost estimation for the new 
&gt; production server that we want to set up before our customer's 
&gt; project will go live.</screen>
            
          </para>
          
          <para>
            Generally, try to keep your attribution short yet
            information-rich. It is <emphasis>not</emphasis> the right place
            for witty quotes,
            long "attribution" novels or anything like that: the right place
            for such things is - if at all - the email signature at the very
            bottom of the message.
          </para>
          
          <para>
            When you're done with writing your message, save and quit the
            editor. As before, you will return to the compose menu, which is
            used in the same way as before.
          </para>
          
          <para>
            
          </para>
          
          <!--}}}-->
        </sect3>
        
        <sect3>
          <title>Group Replies      </title> <!--{{{-->
          
          <para>
            In the situation where a group of people uses email as a
            discussion, most of the emails will have one or more recipients,
            and probably several "Cc:" recipients. The group reply
            functionalityensures that when you press <literal>g</literal>
            instead of <literal>r</literal> to do a reply,
            each and every recipient that is contained in the original message
            will receive a copy of the message, either as normal recipient or
            as "Cc:" recipient.
          </para>
          
          <para>
            
          </para>
          
          <!--}}}-->
        </sect3>
        
        <sect3>
          <title>List Replies      </title> <!--{{{-->
          
          <para>
            When you use mailing lists, it's generally better to send your
            reply to a message only to the list instead of the list and the
            original author. To make this easy to use, mutt-ng features list
            replies.
          </para>
          
          <para>
            To do a list reply, simply press <literal>L</literal>. If the email
            contains
            a <literal>Mail-Followup-To:</literal> header, its value will be
            used as reply
            address. Otherwise, mutt-ng searches through all mail addresses in
            the original message and tries to match them a list of regular
            expressions which can be specified using the <literal>lists</literal> command. 
            If any of the regular expression matches, a mailing
            list address has been found, and it will be used as reply address.
          </para>
          
          <para>
            
            <screen>
lists linuxevent@luga\.at vuln-dev@ mutt-ng-users@</screen>
            
          </para>
          
          <para>
            Nowadays, most mailing list software like GNU Mailman adds a
            <literal>Mail-Followup-To:</literal> header to their emails anyway,
            so setting
            <literal>lists</literal> is hardly ever necessary in practice.
          </para>
          
          <para>
            
          </para>
          
          <para>
            
          </para>
          
          <!--}}}-->
        </sect3>
        
        <!--}}}-->
      </sect2>
      
      <sect2>
        <title>Editing the message header  </title>
        
        <para>
          When editing the header of your outgoing message, there are a couple
          of
          special features available.
        </para>
        
        <para>
          If you specify
          
          <literal>Fcc:</literal> <emphasis>filename</emphasis>
          
          Mutt-ng will pick up <emphasis>filename</emphasis>
          just as if you had used the <emphasis>edit-fcc</emphasis> function in
          the <emphasis>compose</emphasis> menu.
        </para>
        
        <para>
          You can also attach files to your message by specifying
          
          <literal>Attach:</literal> <emphasis>filename</emphasis>  &lsqb; <emphasis>
            description
          </emphasis>
          &rsqb;
          
          where <emphasis>filename</emphasis> is the file to attach and <emphasis>
            description
          </emphasis>
          is an
          optional string to use as the description of the attached file.
        </para>
        
        <para>
          When replying to messages, if you remove the <emphasis>In-Reply-To:</emphasis> field from
          the header field, Mutt-ng will not generate a <emphasis>References:</emphasis> field, which
          allows you to create a new message thread.
        </para>
        
        <para>
          Also see <link linkend="edit-headers">edit-headers</link>.
        </para>
        
        <para>
          
        </para>
        
      </sect2>
      
      <sect2>
        <title>Using Mutt-ng with PGP  </title>
        
        <para>
          If you want to use PGP, you can specify 
        </para>
        
        <para>
          <literal>Pgp:</literal> &lsqb; <literal>E</literal> &verbar; <literal>
            S
          </literal>
          &verbar; <literal>S</literal><emphasis>&lt;id&gt;</emphasis> &rsqb; 
          
        </para>
        
        <para>
          ``E'' encrypts, ``S'' signs and
          ``S&lt;id&gt;'' signs with the given key, setting <link linkend="pgp-sign-as">
            pgp-sign-as
          </link>
          permanently.
        </para>
        
        <para>
          If you have told mutt to PGP encrypt a message, it will guide you
          through a key selection process when you try to send the message.
          Mutt-ng will not ask you any questions about keys which have a
          certified user ID matching one of the message recipients' mail
          addresses.  However, there may be situations in which there are
          several keys, weakly certified user ID fields, or where no matching
          keys can be found.
        </para>
        
        <para>
          In these cases, you are dropped into a menu with a list of keys from
          which you can select one.  When you quit this menu, or mutt can't
          find any matching keys, you are prompted for a user ID.  You can, as
          usually, abort this prompt using <literal>&circ;G</literal>.  When
          you do so, mutt will
          return to the compose screen.
        </para>
        
        <para>
          Once you have successfully finished the key selection, the message
          will be encrypted using the selected public keys, and sent out.
        </para>
        
        <para>
          Most fields of the entries in the key selection menu (see also <link linkend="pgp-entry-format">
            pgp-entry-format
          </link>
          )
          have obvious meanings.  But some explanations on the capabilities,
          flags, 
          and validity fields are in order.
        </para>
        
        <para>
          The flags sequence (&percnt;f) will expand to one of the following
          flags:


        <table>
          <title>PGP Key Menu Flags</title>
          <tgroup cols="2" align="left" colsep="1" rowsep="1">
          <thead>
            <row>
              <entry>Flag</entry>
              <entry>Description</entry>
            </row>
          </thead>
          <tbody>
            <row><entry><code>R      </code></entry><entry>The key has been revoked and can't be used.</entry></row>
            <row><entry><code>X     </code></entry><entry>The key is expired and can't be used.</entry></row>
            <row><entry><code>d     </code></entry><entry>You have marked the key as disabled.</entry></row>
            <row><entry><code>c     </code></entry><entry>There are unknown critical self-signature packets.</entry></row>
          </tbody>
        </tgroup>
      </table>

        </para>
        
        <para>
          The capabilities field (&percnt;c) expands to a two-character
          sequencerepresenting a key's capabilities.  The first character gives
          the key's encryption capabilities: A minus sign (<emphasis role="bold">
            -
          </emphasis>
          )means 
          that the key cannot be used for encryption.  A dot (<emphasis role="bold">
            .
          </emphasis>
          )means that
          it's marked as a signature key in one of the user IDs, but may 
          also be used for encryption.  The letter <emphasis role="bold">e</emphasis> indicates that 
          this key can be used for encryption.
        </para>
        
        <para>
          The second character indicates the key's signing capabilities.  Once 
          again, a ``<emphasis role="bold">-</emphasis>'' implies ``not for
          signing'', ``<emphasis role="bold">.</emphasis>'' implies
          that the key is marked as an encryption key in one of the user-ids,
          and
          ``<emphasis role="bold">s</emphasis>'' denotes a key which can be
          used for signing.
        </para>
        
        <para>
          Finally, the validity field (&percnt;t) indicates how well-certified
          a user-id
          is.  A question mark (<emphasis role="bold">?</emphasis>) indicates
          undefined validity, a minus 
          character (<emphasis role="bold">-</emphasis>) marks an untrusted
          association, a space character 
          means a partially trusted association, and a plus character (<emphasis role="bold">
            +
          </emphasis>
          )
          indicates complete validity.
        </para>
        
        <para>
          
        </para>
        
      </sect2>
      
      <sect2>
        <title>Sending anonymous messages via mixmaster  </title>
        
        <para>
          You may also have configured mutt to co-operate with Mixmaster, an
          anonymous remailer.  Mixmaster permits you to send your messages
          anonymously using a chain of remailers. Mixmaster support in mutt is
          for 
          mixmaster version 2.04 (beta 45 appears to be the latest) and 2.03. 
          It does not support earlier versions or the later so-called version 3
          betas, 
          of which the latest appears to be called 2.9b23.
        </para>
        
        <para>
          To use it, you'll have to obey certain restrictions.  Most
          important, you cannot use the <literal>Cc</literal> and <literal>Bcc</literal> headers.  To tell
          Mutt-ng to use mixmaster, you have to select a remailer chain, using
          the mix function on the compose menu.  
        </para>
        
        <para>
          The chain selection screen is divided into two parts.  In the
          (larger) upper part, you get a list of remailers you may use.  In
          the lower part, you see the currently selected chain of remailers.
        </para>
        
        <para>
          You can navigate in the chain using the <literal>chain-prev</literal>
          and
          <literal>chain-next</literal> functions, which are by default bound
          to the left
          and right arrows and to the <literal>h</literal> and <literal>l</literal> keys (think vi
          keyboard bindings).  To insert a remailer at the current chain
          position, use the <literal>insert</literal> function.  To append a
          remailer behind
          the current chain position, use <literal>select-entry</literal> or <literal>
            append
          </literal>
          .
          You can also delete entries from the chain, using the corresponding
          function.  Finally, to abandon your changes, leave the menu, or
          <literal>accept</literal> them pressing (by default) the <literal>
            Return
          </literal>
          key.
        </para>
        
        <para>
          Note that different remailers do have different capabilities,
          indicated in the &percnt;c entry of the remailer menu lines (see
          <link linkend="mix-entry-format">mix-entry-format</link>).  Most
          important is
          the ``middleman'' capability, indicated by a capital ``M'': This
          means that the remailer in question cannot be used as the final
          element of a chain, but will only forward messages to other
          mixmaster remailers.  For details on the other capabilities, please
          have a look at the mixmaster documentation.
        </para>
        
        <para>
          
        </para>
        
        <para>
          
        </para>
        
      </sect2>
      
    </sect1>
    
    <sect1 id="forwarding-mail">
      <title>Forwarding and Bouncing Mail  </title>
      
      <para>
        Often, it is necessary to forward mails to other people.
        Therefore, mutt-ng supports forwarding messages in two different
        ways.
      </para>
      
      <para>
        The first one is regular forwarding, as you probably know it from
        other mail clients. You simply press <literal>f</literal>, enter the
        recipient
        email address, the subject of the forwarded email, and then you can
        edit the message to be forwarded in the editor. The forwarded
        message is separated from the rest of the message via the two
        following markers:
      </para>
      
      <para>
        
        <screen>
----- Forwarded message from Lucas User &#60;luser@example.com&#62; -----

From: Lucas User &#60;luser@example.com&#62;
Date: Thu, 02 Dec 2004 03:08:34 +0100
To: Michael Random &#60;mrandom@example.com&#62;
Subject: Re: blackmail

Pay me EUR 50,000.- cash or your favorite stuffed animal will die
a horrible death.

----- End forwarded message -----</screen>
        
      </para>
      
      <para>
        When you're done with editing the mail, save and quit the editor,
        and you will return to the compose menu, the same menu you also
        encounter when composing or replying to mails.
      </para>
      
      <para>
        The second mode of forwarding emails with mutt-ng is the
        so-called <emphasis>bouncing</emphasis>: when you bounce an email to
        another
        address, it will be sent in practically the same format you send it
        (except for headers that are created during transporting the
        message). To bounce a message, press <literal>b</literal> and enter the
        recipient
        email address. By default, you are then asked whether you really
        want to bounce the message to the specified recipient. If you answer
        with yes, the message will then be bounced.
      </para>
      
      <para>
        To the recipient, the bounced email will look as if he got it
        like a regular email where he was <literal>Bcc:</literal> recipient.
        The only
        possibility to find out whether it was a bounced email is to
        carefully study the email headers and to find out which host really
        sent the email.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="postponing-mail">
      <title>Postponing Mail  </title>
      
      <para>
        At times it is desirable to delay sending a message that you have
        already begun to compose.  When the <emphasis>postpone-message</emphasis> function is
        used in the <emphasis>compose</emphasis> menu, the body of your message
        and attachments
        are stored in the mailbox specified by the <link linkend="postponed">
          postponed
        </link>
        variable.  This means that you can recall the
        message even if you exit Mutt-ng and then restart it at a later time.
      </para>
      
      <para>
        Once a message is postponed, there are several ways to resume it.  From
        the
        command line you can use the ``-p'' option, or if you <emphasis>compose</emphasis> a new
        message from the <emphasis>index</emphasis> or <emphasis>pager</emphasis> you will be prompted if postponed
        messages exist.  If multiple messages are currently postponed, the
        <emphasis>postponed</emphasis> menu will pop up and you can select
        which message you would
        like to resume.
      </para>
      
      <para>
        <emphasis role="bold">Note:</emphasis> If you postpone a reply to a
        message, the reply setting of
        the message is only updated when you actually finish the message and
        send it.  Also, you must be in the same folder with the message you
        replied to for the status of the message to be updated.
      </para>
      
      <para>
        See also the <link linkend="postpone">postpone</link> quad-option.
      </para>
      
      <para>
        
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
  </chapter>
  
  <chapter>
    <title>Configuration  </title>
    
    <sect1>
      <title>Locations of Configuration Files  </title>
      
      <para>
        While the default configuration (or ``preferences'') make Mutt-ng
        usable right out
        of the box, it is often desirable to tailor Mutt-ng to suit your own
        tastes. When
        Mutt-ng is first invoked, it will attempt to read the ``system''
        configuration
        file (defaults set by your local system administrator), unless the
        ``-n'' <link linkend="commandline">commandline</link> option is
        specified.  This file is
        typically <literal>/usr/local/share/muttng/Muttngrc</literal> or <literal>
          /etc/Muttngrc
        </literal>
        ,
        Mutt-ng users will find this file in <literal>
          /usr/local/share/muttng/Muttrc
        </literal>
        or
        <literal>/etc/Muttngrc</literal>. Mutt will next look for a file named <literal>
          .muttrc
        </literal>
        in your home directory, Mutt-ng will look for <literal>.muttngrc</literal>.  If this file
        does not exist and your home directory has a subdirectory named <literal>
          .mutt
        </literal>
        ,
        mutt try to load a file named <literal>.muttng/muttngrc</literal>. 
      </para>
      
      <para>
        <literal>.muttrc</literal> (or <literal>.muttngrc</literal> for
        Mutt-ng) is the file where you will
        usually place your <link linkend="commands">commands</link> to
        configure Mutt-ng.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="muttrc-syntax">
      <title>Basic Syntax of Initialization Files  </title>
      
      <para>
        An initialization file consists of a series of <link linkend="commands">
          commands
        </link>
        .Each line of the file may contain one or more commands.
        When multiple commands are used, they must be separated by a semicolon
        (;).
        
        <screen>
set realname='Mutt-ng user' ; ignore x-</screen>
        
        The hash mark, or pound sign
        (``&num;''), is used as a ``comment'' character. You can use it to
        annotate your initialization file. All text after the comment character
        to the end of the line is ignored. For example,
      </para>
      
      <para>
        
        <screen>
my_hdr X-Disclaimer: Why are you listening to me? &num; This is a comment</screen>
        
      </para>
      
      <para>
        Single quotes (') and double quotes (&quot;) can be used to quote
        strings
        which contain spaces or other special characters.  The difference
        between
        the two types of quotes is similar to that of many popular shell
        programs,
        namely that a single quote is used to specify a literal string (one
        that is
        not interpreted for shell variables or quoting with a backslash
        &lsqb;see
        next paragraph&rsqb;), while double quotes indicate a string for which
        should be evaluated.  For example, backtics are evaluated inside of
        double
        quotes, but <emphasis role="bold">not</emphasis> for single quotes.
      </para>
      
      <para>
        &bsol; quotes the next character, just as in shells such as bash and
        zsh.
        For example, if want to put quotes ``&quot;'' inside of a string, you
        can use
        ``&bsol;'' to force the next character to be a literal instead of
        interpreted
        character.
        
        <screen>
set realname="Michael \"MuttDude\" Elkins"</screen>
        
      </para>
      
      <para>
        ``&bsol;&bsol;'' means to insert a literal ``&bsol;'' into the line.
        ``&bsol;n'' and ``&bsol;r'' have their usual C meanings of linefeed and
        carriage-return, respectively.
      </para>
      
      <para>
        A &bsol; at the end of a line can be used to split commands over
        multiple lines, provided that the split points don't appear in the
        middle of command names.
      </para>
      
      <para>
        Please note that, unlike the various shells, mutt-ng interprets a
        ``&bsol;''
        at the end of a line also in comments. This allows you to disable a
        command
        split over multiple lines with only one ``&num;''.
      </para>
      
      <para>
        
        <screen>
# folder-hook . \
set realname="Michael \"MuttDude\" Elkins"</screen>
        
      </para>
      
      <para>
        When testing your config files, beware the following caveat. The
        backslash
        at the end of the commented line extends the current line with the next
        line
        - then referred to as a ``continuation line''.  As the first line is
        commented with a hash (&num;) all following continuation lines are also
        part of a comment and therefore are ignored, too. So take care of
        comments
        when continuation lines are involved within your setup files!
      </para>
      
      <para>
        Abstract example:
      </para>
      
      <para>
        
        <screen>
line1\
line2a # line2b\
line3\
line4
line5</screen>
        
      </para>
      
      <para>
        line1 ``continues'' until line4. however, the part after the &num; is a
        comment which includes line3 and line4. line5 is a new line of its own
        and
        thus is interpreted again.
      </para>
      
      <para>
        The commands understood by mutt are explained in the next paragraphs.
        For a complete list, see the <link linkend="commands">commands</link>.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1>
      <title>Expansion within variables    </title>
      
      <para>
        Besides just assign static content to variables, there's plenty of
        ways of adding external and more or less dynamic content.
      </para>
      
      <sect2>
        <title>Commands' Output     </title>
        
        <para>
          It is possible to substitute the output of a Unix command in an
          initialization file.  This is accomplished by enclosing the command
          in backquotes (``) as in, for example:
        </para>
        
        <para>
          
          <screen>
my_hdr X-Operating-System: `uname -a`</screen>
          
        </para>
        
        <para>
          The output of the Unix command ``uname -a'' will be substituted
          before the line is parsed. Note that since initialization files are
          line oriented, only the first line of output from the Unix command
          will be substituted.
        </para>
        
      </sect2>
      
      <sect2>
        <title>Environment Variables     </title>
        
        <para>
          UNIX environments can be accessed like the way it is done in
          shells like sh and bash: Prepend the name of the environment by a
          ``&dollar;'' sign. For example,
        </para>
        
        <para>
          
          <screen>
set record=+sent_on_$HOSTNAME</screen>
          
        </para>
        
        <para>
          sets the <link linkend="record">record</link> variable to the
          string <emphasis>+sent&lowbar;on&lowbar;</emphasis> and appends the
          value of the evironment
          variable <literal>&dollar;HOSTNAME</literal>.
        </para>
        
        <para>
          <emphasis role="bold">Note:</emphasis> There will be no warning if an
          environment variable
          is not defined. The result will of the expansion will then be empty.
        </para>
        
      </sect2>
      
      <sect2>
        <title>Configuration Variables     </title>
        
        <para>
          As for environment variables, the values of all configuration
          variables as string can be used in the same way, too. For example,
        </para>
        
        <para>
          
          <screen>
set imap_home_namespace = $folder</screen>
          
        </para>
        
        <para>
          would set the value of <link linkend="imap-home-namespace">
            imap-home-namespace
          </link>
          to the value to
          which <link linkend="folder">folder</link> is <emphasis>currently</emphasis> set
          to.
        </para>
        
        <para>
          <emphasis role="bold">Note:</emphasis> There're no logical links
          established in such cases so
          that the the value for <link linkend="imap-home-namespace">
            imap-home-namespace
          </link>
          won't change even
          if <link linkend="folder">folder</link> gets changed.
        </para>
        
        <para>
          <emphasis role="bold">Note:</emphasis> There will be no warning if a
          configuration variable
          is not defined or is empty. The result will of the expansion will
          then be empty.
        </para>
        
      </sect2>
      
      <sect2>
        <title>Self-Defined Variables     </title>
        
        <para>
          Mutt-ng flexibly allows users to define their own variables. To
          avoid conflicts with the standard set and to prevent misleading
          error messages, there's a reserved namespace for them: all
          user-defined variables must be prefixed with <literal>user&lowbar;</literal> and can be
          used just like any ordinary configuration or environment
          variable.
        </para>
        
        <para>
          For example, to view the manual, users can either define two
          macros like the following
        </para>
        
        <para>
          
          <screen>
macro generic &lt;F1&gt; "!less -r /path/to/manual" "Show manual"
macro pager &lt;F1&gt; "!less -r /path/to/manual" "Show manual"</screen>
          
        </para>
        
        <para>
          for <literal>generic</literal>, <literal>pager</literal> and <literal>
            index
          </literal>
          .The alternative is to
          define a custom variable like so:
        </para>
        
        <para>
          
          <screen>
set user_manualcmd = "!less -r /path/to_manual" 
macro generic &lt;F1&gt; "$user_manualcmd&lt;enter&gt;" "Show manual"
macro pager &lt;F1&gt; "$user_manualcmd&lt;enter&gt;" "Show manual"
macro index &lt;F1&gt; "$user_manualcmd&lt;enter&gt;" "Show manual"</screen>
          
        </para>
        
        <para>
          to re-use the command sequence as in:
        </para>
        
        <para>
          
          <screen>
macro index &lt;F2&gt; "$user_manualcmd | grep '\^[ ]\\+~. '" "Show Patterns"</screen>
          
        </para>
        
        <para>
          Using this feature, arbitrary sequences can be defined once and
          recalled and reused where necessary. More advanced scenarios could
          include to save a variable's value at the beginning of macro
          sequence and restore it at end.
        </para>
        
        <para>
          When the variable is first defined, the first value it gets
          assigned is also the initial value to which it can be reset using
          the <literal>reset</literal> command.
        </para>
        
        <para>
          The complete removal is done via the <literal>unset</literal>
          keyword.
        </para>
        
        <para>
          After the following sequence:
        </para>
        
        <para>
          
          <screen>
set user_foo = 42
set user_foo = 666</screen>
          
        </para>
        
        <para>
          the variable <literal>$user&lowbar;foo</literal> has a current value
          of 666 and an
          initial of 42. The query
        </para>
        
        <para>
          
          <screen>
set ?user_foo</screen>
          
        </para>
        
        <para>
          will show 666. After doing the reset via
        </para>
        
        <para>
          
          <screen>
reset user_foo</screen>
          
        </para>
        
        <para>
          a following query will give 42 as the result. After unsetting it
          via
        </para>
        
        <para>
          
          <screen>
unset user_foo</screen>
          
        </para>
        
        <para>
          any query or operation (except the noted expansion within other
          statements) will lead to an error message.
        </para>
        
      </sect2>
      
      <sect2>
        <title>Pre-Defined Variables     </title>
        
        <para>
          In order to allow users to share one setup over a number of
          different machines without having to change its contents, there's a
          number of pre-defined variables. These are prefixed with
          <literal>muttng&lowbar;</literal> and are read-only, i.e. they cannot
          be set, unset or
          reset. The reference chapter lists all available variables.
        </para>
        
        <para>
          <emphasis> Please consult the local copy of your manual for their
            values as they may differ from different manual sources.
          </emphasis>
          Where
          the manual is installed in can be queried (already using such a
          variable) by running:
        </para>
        
        <para>
          
          <screen>
muttng -Q muttng_docdir</screen>
          
        </para>
        
        <para>
          To extend the example for viewing the manual via self-defined
          variables, it can be made more readable and more portable by
          changing the real path in:
        </para>
        
        <para>
          
          <screen>
set user_manualcmd = '!less -r /path/to_manual'</screen>
          
        </para>
        
        <para>
          to:
        </para>
        
        <para>
          
          <screen>
set user_manualcmd = "!less -r $muttng_docdir/manual.txt"</screen>
          
        </para>
        
        <para>
          which works everywhere if a manual is installed.
        </para>
        
        <para>
          Please note that by the type of quoting, muttng determines when
          to expand these values: when it finds double quotes, the value will
          be expanded during reading the setup files but when it finds single
          quotes, it'll expand it at runtime as needed.
        </para>
        
        <para>
          For example, the statement
        </para>
        
        <para>
          
          <screen>
folder-hook . "set user_current_folder = $muttng_folder_name"</screen>
          
        </para>
        
        <para>
          will be already be translated to the following when reading the
          startup files:
        </para>
        
        <para>
          
          <screen>
folder-hook . "set user_current_folder = some_folder"</screen>
          
        </para>
        
        <para>
          with <literal>some&lowbar;folder</literal> being the name of the
          first folder muttng
          opens. On the contrary,
        </para>
        
        <para>
          
          <screen>
folder-hook . 'set user_current_folder = $muttng_folder_name'</screen>
          
        </para>
        
        <para>
          will be executed at runtime because of the single quotes so that
          <literal>user&lowbar;current&lowbar;folder</literal> will always have
          the value of the currently
          opened folder.
        </para>
        
        <para>
          A more practical example is:
        </para>
        
        <para>
          
          <screen>
folder-hook . 'source ~/.mutt/score-$muttng_folder_name'</screen>
          
        </para>
        
        <para>
          which can be used to source files containing score commands
          depending on the folder the user enters.
        </para>
        
      </sect2>
      
      <sect2>
        <title>Type Conversions     </title>
        
        <para>
          A note about variable's types during conversion: internally
          values are stored in internal types but for any dump/query or set
          operation they're converted to and from string. That means that
          there's no need to worry about types when referencing any variable.
          As an example, the following can be used without harm (besides
          makeing muttng very likely behave strange):
        </para>
        
        <para>
          
          <screen>
set read_inc = 100
set folder = $read_inc
set read_inc = $folder
set user_magic_number = 42
set folder = $user_magic_number</screen>
          
        </para>
        
      </sect2>
      
    </sect1>
    
    <sect1 id="alias">
      <title>Defining/Using aliases  </title>
      
      <para>
        Usage: <literal>alias</literal> <emphasis>key</emphasis> <emphasis>
          address
        </emphasis>
        &lsqb; , <emphasis>address</emphasis>, ... &rsqb;
      </para>
      
      <para>
        It's usually very cumbersome to remember or type out the address of
        someone
        you are communicating with.  Mutt-ng allows you to create ``aliases''
        which map
        a short string to a full address.
      </para>
      
      <para>
        <emphasis role="bold">Note:</emphasis> if you want to create an alias
        for a group (by specifying more than
        one address), you <emphasis role="bold">must</emphasis> separate the
        addresses with a comma (``,'').
      </para>
      
      <para>
        To remove an alias or aliases (``*'' means all aliases):
      </para>
      
      <para>
        <literal>unalias</literal> &lsqb; * &verbar; <emphasis>key</emphasis> <emphasis>
          ...
        </emphasis>
        &rsqb;
      </para>
      
      <para>
        
        <screen>
alias muttdude me@cs.hmc.edu (Michael Elkins)
alias theguys manny, moe, jack</screen>
        
      </para>
      
      <para>
        Unlike other mailers, Mutt-ng doesn't require aliases to be defined
        in a special file.  The <literal>alias</literal> command can appear
        anywhere in
        a configuration file, as long as this file is <link linkend="source">
          source
        </link>
        .Consequently, you can have multiple alias files, or
        you can have all aliases defined in your muttrc.
      </para>
      
      <para>
        On the other hand, the <link linkend="create-alias">create-alias</link>
        function can use only one file, the one pointed to by the <link linkend="alias-file">
          alias-file
        </link>
        variable (which is
        <literal>&tilde;/.muttrc</literal> by default). This file is not
        special either,
        in the sense that Mutt-ng will happily append aliases to any file, but
        in
        order for the new aliases to take effect you need to explicitly <link linkend="source">
          source
        </link>
        this file too.
      </para>
      
      <para>
        For example:
      </para>
      
      <para>
        
        <screen>
source /usr/local/share/Mutt-ng.aliases
source ~/.mail_aliases
set alias_file=~/.mail_aliases</screen>
        
      </para>
      
      <para>
        To use aliases, you merely use the alias at any place in mutt where
        muttprompts for addresses, such as the <emphasis>To:</emphasis> or <emphasis>
          Cc:
        </emphasis>
        prompt.  You can
        also enter aliases in your editor at the appropriate headers if you
        have the
        <link linkend="edit-headers">edit-headers</link> variable set.
      </para>
      
      <para>
        In addition, at the various address prompts, you can use the tab
        character
        to expand a partial alias to the full alias.  If there are multiple
        matches,
        mutt will bring up a menu with the matching aliases.  In order to be
        presented with the full list of aliases, you must hit tab with out a
        partial
        alias, such as at the beginning of the prompt or after a comma denoting
        multiple addresses.
      </para>
      
      <para>
        In the alias menu, you can select as many aliases as you want with the
        <emphasis>select-entry</emphasis> key (default: RET), and use the <emphasis>
          exit
        </emphasis>
        key
        (default: q) to return to the address prompt.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="bind">
      <title>Changing the default key bindings  </title>
      
      <para>
        Usage: <literal>bind</literal> <emphasis>map</emphasis> <emphasis>key</emphasis> <emphasis>
          function
        </emphasis>
      </para>
      
      <para>
        This command allows you to change the default key bindings (operation
        invoked when pressing a key).
      </para>
      
      <para>
        <emphasis>map</emphasis> specifies in which menu the binding belongs. 
        Multiple maps may
        be specified by separating them with commas (no additional whitespace
        isallowed). The currently defined maps are:
      </para>
      
      <para>
        <anchor id="maps"/>
        <variablelist>
          
          <varlistentry>
            <term>generic</term>
            <listitem>
              <para>
                This is not a real menu, but is used as a fallback for all of
                the other
                menus except for the pager and editor modes.  If a key is not
                defined in
                another menu, Mutt-ng will look for a binding to use in this
                menu.  This allows
                you to bind a key to a certain function in multiple menus
                instead of having
                multiple bind statements to accomplish the same task.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>alias</term>
            <listitem>
              <para>
                The alias menu is the list of your personal aliases as defined
                in your
                muttrc.  It is the mapping from a short alias name to the full
                email
                address(es) of the recipient(s).
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>attach</term>
            <listitem>
              <para>
                The attachment menu is used to access the attachments on
                received messages.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>browser</term>
            <listitem>
              <para>
                The browser is used for both browsing the local directory
                structure, and for
                listing all of your incoming mailboxes.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>editor</term>
            <listitem>
              <para>
                The editor is the line-based editor the user enters text data.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>index</term>
            <listitem>
              <para>
                The index is the list of messages contained in a mailbox.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>compose</term>
            <listitem>
              <para>
                The compose menu is the screen used when sending a new message.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>pager</term>
            <listitem>
              <para>
                The pager is the mode used to display message/attachment data,
                and help
                listings.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>pgp</term>
            <listitem>
              <para>
                The pgp menu is used to select the OpenPGP keys used for
                encrypting outgoing
                messages.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>postpone</term>
            <listitem>
              <para>
                The postpone menu is similar to the index menu, except is used
                when
                recalling a message the user was composing, but saved until
                later.
              </para>
            </listitem>
          </varlistentry>
        </variablelist>
      </para>
      
      <para>
        <emphasis>key</emphasis> is the key (or key sequence) you wish to bind.
         To specify a
        control character, use the sequence <emphasis>&bsol;Cx</emphasis>,
        where <emphasis>x</emphasis> is the
        letter of the control character (for example, to specify control-A use
        ``&bsol;Ca'').  Note that the case of <emphasis>x</emphasis> as well as
        <emphasis>&bsol;C</emphasis> is
        ignored, so that <emphasis>&bsol;CA</emphasis>, <emphasis>&bsol;Ca</emphasis>, <emphasis>
          &bsol;cA
        </emphasis>
        and <emphasis>&bsol;ca</emphasis> are all
        equivalent.  An alternative form is to specify the key as a three digit
        octal number prefixed with a ``&bsol;'' (for example <emphasis>
          &bsol;177
        </emphasis>
        is
        equivalent to <emphasis>&bsol;c?</emphasis>).
      </para>
      
      <para>
        In addition, <emphasis>key</emphasis> may consist of:
      </para>
      
      <para>
        
        <table>
          <title>Alternative Key Names</title>
          <tgroup cols="2" align="left" colsep="1" rowsep="1">
          <thead>
            <row>
              <entry>Sequence</entry>
              <entry>Description</entry>
            </row>
          </thead>
          <tbody>
            <row><entry><code>\t     </code></entry><entry>tab</entry></row>
            <row><entry><code>&#60;tab&#62;      </code></entry><entry>tab</entry></row>
            <row><entry><code>&#60;backtab&#62;   </code></entry><entry>backtab / shift-tab</entry></row>
            <row><entry><code>\r    </code></entry><entry>carriage return</entry></row>
            <row><entry><code>\n     </code></entry><entry>newline</entry></row>
            <row><entry><code>\e      </code></entry><entry>escape</entry></row>
            <row><entry><code>&#60;esc&#62;   </code></entry><entry>escape</entry></row>
            <row><entry><code>&#60;up&#62;     </code></entry><entry>up arrow</entry></row>
            <row><entry><code>&#60;down&#62;     </code></entry><entry>down arrow</entry></row>
            <row><entry><code>&#60;left&#62;     </code></entry><entry>left arrow</entry></row>
            <row><entry><code>&#60;right&#62;    </code></entry><entry>right arrow</entry></row>
            <row><entry><code>&#60;pageup&#62;   </code></entry><entry>Page Up</entry></row>
            <row><entry><code>&#60;pagedown&#62;  </code></entry><entry>Page Down</entry></row>
            <row><entry><code>&#60;backspace&#62;  </code></entry><entry>Backspace</entry></row>
            <row><entry><code>&#60;delete&#62;    </code></entry><entry>Delete</entry></row>
            <row><entry><code>&#60;insert&#62;     </code></entry><entry>Insert</entry></row>
            <row><entry><code>&#60;enter&#62;    </code></entry><entry>Enter</entry></row>
            <row><entry><code>&#60;return&#62;   </code></entry><entry>Return</entry></row>
            <row><entry><code>&#60;home&#62;     </code></entry><entry>Home</entry></row>
            <row><entry><code>&#60;end&#62;      </code></entry><entry>End</entry></row>
            <row><entry><code>&#60;space&#62;    </code></entry><entry>Space bar</entry></row>
            <row><entry><code>&#60;f1&#62;       </code></entry><entry>function key 1</entry></row>
            <row><entry><code>&#60;f10&#62;       </code></entry><entry>function key 10</entry></row>
          </tbody>
        </tgroup>
      </table>
        
      </para>
      
      <para>
        <emphasis>key</emphasis> does not need to be enclosed in quotes unless
        it contains a
        space (`` '').
      </para>
      
      <para>
        <emphasis>function</emphasis> specifies which action to take when <emphasis>
          key
        </emphasis>
        is pressed.
        For a complete list of functions, see the <link linkend="functions">
          functions
        </link>
        .The special function <literal>noop</literal> unbinds the specified key
        sequence.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="charset-hook">
      <title>Defining aliases for character sets   </title>
      
      <para>
        Usage: <literal>charset-hook</literal> <emphasis>alias</emphasis> <emphasis>
          charset
        </emphasis>
        
        Usage: <literal>iconv-hook</literal> <emphasis>charset</emphasis> <emphasis>
          local-charset
        </emphasis>
      </para>
      
      <para>
        The <literal>charset-hook</literal> command defines an alias for a
        character set.
        This is useful to properly display messages which are tagged with a
        character set name not known to mutt.
      </para>
      
      <para>
        The <literal>iconv-hook</literal> command defines a system-specific
        name for a
        character set.  This is helpful when your systems character
        conversion library insists on using strange, system-specific names
        for character sets.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="folder-hook">
      <title>Setting variables based upon mailbox  </title>
      
      <para>
        Usage: <literal>folder-hook</literal> &lsqb;!&rsqb;<emphasis>regexp</emphasis> <emphasis>
          command
        </emphasis>
      </para>
      
      <para>
        It is often desirable to change settings based on which mailbox you are
        reading.  The folder-hook command provides a method by which you can
        execute
        any configuration command.  <emphasis>regexp</emphasis> is a regular
        expression specifying
        in which mailboxes to execute <emphasis>command</emphasis> before
        loading.  If a mailbox
        matches multiple folder-hook's, they are executed in the order given in
        the
        muttrc.
      </para>
      
      <para>
        <emphasis role="bold">Note:</emphasis> if you use the ``!'' shortcut
        for <link linkend="spoolfile">spoolfile</link> at the beginning of the
        pattern, you must place it
        inside of double or single quotes in order to distinguish it from the
        logical <emphasis>not</emphasis> operator for the expression.
      </para>
      
      <para>
        Note that the settings are <emphasis>not</emphasis> restored when you
        leave the mailbox.
        For example, a command action to perform is to change the sorting
        methodbased upon the mailbox being read:
      </para>
      
      <para>
        
        <screen>
folder-hook mutt set sort=threads</screen>
        
      </para>
      
      <para>
        However, the sorting method is not restored to its previous value when
        reading a different mailbox.  To specify a <emphasis>default</emphasis>
        command, use the
        pattern ``.'':
      </para>
      
      <para>
        
        <screen>
folder-hook . set sort=date-sent</screen>
        
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="macro">
      <title>Keyboard macros  </title>
      
      <para>
        Usage: <literal>macro</literal> <emphasis>menu</emphasis> <emphasis>key</emphasis> <emphasis>
          sequence
        </emphasis>
        &lsqb; <emphasis>description</emphasis> &rsqb;
      </para>
      
      <para>
        Macros are useful when you would like a single key to perform a series
        of
        actions.  When you press <emphasis>key</emphasis> in menu <emphasis>
          menu
        </emphasis>
        ,Mutt-ng will behave as if
        you had typed <emphasis>sequence</emphasis>.  So if you have a common
        sequence of commands
        you type, you can create a macro to execute those commands with a
        singlekey.
      </para>
      
      <para>
        <emphasis>menu</emphasis> is the <link linkend="maps">maps</link> which
        the macro will be bound.
        Multiple maps may be specified by separating multiple menu arguments by
        commas. Whitespace may not be used in between the menu arguments and
        thecommas separating them.
      </para>
      
      <para>
        <emphasis>key</emphasis> and <emphasis>sequence</emphasis> are expanded
        by the same rules as the <link linkend="bind">bind</link>.  There are
        some additions however.  The
        first is that control characters in <emphasis>sequence</emphasis> can
        also be specified
        as <emphasis>&circ;x</emphasis>.  In order to get a caret (`&circ;'')
        you need to use
        <emphasis>&circ;&circ;</emphasis>.  Secondly, to specify a certain key
        such as <emphasis>up</emphasis>
        or to invoke a function directly, you can use the format
        <emphasis>&lt;key name&gt;</emphasis> and <emphasis>&lt;function
          name&gt;
        </emphasis>
        .For a listing of key
        names see the section on <link linkend="bind">bind</link>.  Functions
        are listed in the <link linkend="functions">functions</link>.
      </para>
      
      <para>
        The advantage with using function names directly is that the macros
        willwork regardless of the current key bindings, so they are not
        dependent on
        the user having particular key definitions.  This makes them more
        robustand portable, and also facilitates defining of macros in files
        used by more
        than one user (eg. the system Muttngrc).
      </para>
      
      <para>
        Optionally you can specify a descriptive text after <emphasis>sequence</emphasis>,
        which is shown in the help screens.
      </para>
      
      <para>
        <emphasis role="bold">Note:</emphasis> Macro definitions (if any)
        listed in the help screen(s), are
        silently truncated at the screen width, and are not wrapped.   
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="color">
      <title>Using color and mono video attributes  </title>
      
      <para>
        Usage: <literal>color</literal> <emphasis>object</emphasis> <emphasis>
          foreground
        </emphasis>
        <emphasis>background</emphasis> &lsqb; <emphasis>regexp</emphasis>
        &rsqb;
        
        Usage: <literal>color</literal> index <emphasis>foreground</emphasis> <emphasis>
          background
        </emphasis>
        <emphasis>pattern</emphasis>
        
        Usage: <literal>uncolor</literal> index <emphasis>pattern</emphasis>
        &lsqb; <emphasis>pattern</emphasis> ...  &rsqb;
        
      </para>
      
      <para>
        If your terminal supports color, you can spice up Mutt-ng by creating
        your own
        color scheme.  To define the color of an object (type of information),
        you
        must specify both a foreground color <emphasis role="bold">and</emphasis> a background color (it is not
        possible to only specify one or the other).
      </para>
      
      <para>
        <emphasis>object</emphasis> can be one of:
      </para>
      
      <para>
        
        <itemizedlist>
          <listitem>
            
            <para>
              attachment
            </para>
          </listitem>
          <listitem>
            
            <para>
              body (match <emphasis>regexp</emphasis> in the body of messages)
            </para>
          </listitem>
          <listitem>
            
            <para>
              bold (highlighting bold patterns in the body of messages)
            </para>
          </listitem>
          <listitem>
            
            <para>
              error (error messages printed by Mutt-ng)
            </para>
          </listitem>
          <listitem>
            
            <para>
              header (match <emphasis>regexp</emphasis> in the message header)
            </para>
          </listitem>
          <listitem>
            
            <para>
              hdrdefault (default color of the message header in the pager)
            </para>
          </listitem>
          <listitem>
            
            <para>
              index (match <emphasis>pattern</emphasis> in the message index)
            </para>
          </listitem>
          <listitem>
            
            <para>
              indicator (arrow or bar used to indicate the current item in a
              menu)
            </para>
          </listitem>
          <listitem>
            
            <para>
              markers (the ``+'' markers at the beginning of wrapped lines in
              the pager)
            </para>
          </listitem>
          <listitem>
            
            <para>
              message (informational messages)
            </para>
          </listitem>
          <listitem>
            
            <para>
              normal
            </para>
          </listitem>
          <listitem>
            
            <para>
              quoted (text matching <link linkend="quote-regexp">quote-regexp</link> in the body of a message)
            </para>
          </listitem>
          <listitem>
            
            <para>
              quoted1, quoted2, ..., quoted<emphasis role="bold">N</emphasis>
              (higher levels of quoting)
            </para>
          </listitem>
          <listitem>
            
            <para>
              search (highlighting of words in the pager)
            </para>
          </listitem>
          <listitem>
            
            <para>
              signature
            </para>
          </listitem>
          <listitem>
            
            <para>
              status (mode lines used to display info about the mailbox or
              message)
            </para>
          </listitem>
          <listitem>
            
            <para>
              tilde (the ``&tilde;'' used to pad blank lines in the pager)
            </para>
          </listitem>
          <listitem>
            
            <para>
              tree (thread tree drawn in the message index and attachment menu)
            </para>
          </listitem>
          <listitem>
            
            <para>
              underline (highlighting underlined patterns in the body of
              messages)
            </para>
          </listitem>
          
        </itemizedlist>
        
      </para>
      
      <para>
        <emphasis>foreground</emphasis> and <emphasis>background</emphasis> can
        be one of the following:
      </para>
      
      <para>
        
        <itemizedlist>
          <listitem>
            
            <para>
              white
            </para>
          </listitem>
          <listitem>
            
            <para>
              black
            </para>
          </listitem>
          <listitem>
            
            <para>
              green
            </para>
          </listitem>
          <listitem>
            
            <para>
              magenta
            </para>
          </listitem>
          <listitem>
            
            <para>
              blue
            </para>
          </listitem>
          <listitem>
            
            <para>
              cyan
            </para>
          </listitem>
          <listitem>
            
            <para>
              yellow
            </para>
          </listitem>
          <listitem>
            
            <para>
              red
            </para>
          </listitem>
          <listitem>
            
            <para>
              default
            </para>
          </listitem>
          <listitem>
            
            <para>
              color<emphasis>x</emphasis>
            </para>
          </listitem>
          
        </itemizedlist>
        
      </para>
      
      <para>
        <emphasis>foreground</emphasis> can optionally be prefixed with the
        keyword <literal>bright</literal> to make
        the foreground color boldfaced (e.g., <literal>brightred</literal>).
      </para>
      
      <para>
        If your terminal supports it, the special keyword <emphasis>default</emphasis> can be
        used as a transparent color.  The value <emphasis>brightdefault</emphasis> is also valid.
        If Mutt-ng is linked against the <emphasis>S-Lang</emphasis> library,
        you also need to set
        the <emphasis>COLORFGBG</emphasis> environment variable to the default
        colors of your
        terminal for this to work; for example (for Bourne-like shells):
      </para>
      
      <para>
        
        <screen>
set COLORFGBG="green;black"
export COLORFGBG</screen>
        
      </para>
      
      <para>
        <emphasis role="bold">Note:</emphasis> The <emphasis>S-Lang</emphasis>
        library requires you to use the <emphasis>lightgray</emphasis>
        and <emphasis>brown</emphasis> keywords instead of <emphasis>white</emphasis> and <emphasis>
          yellow
        </emphasis>
        when
        setting this variable.
      </para>
      
      <para>
        <emphasis role="bold">Note:</emphasis> The uncolor command can be
        applied to the index object only.  It
        removes entries from the list. You <emphasis role="bold">must</emphasis> specify the same pattern
        specified in the color command for it to be removed.  The pattern ``*''
        is
        a special token which means to clear the color index list of all
        entries.
      </para>
      
      <para>
        Mutt-ng also recognizes the keywords <emphasis>color0</emphasis>, <emphasis>
          color1
        </emphasis>
        ,&hellip;,
        <emphasis>color</emphasis><emphasis role="bold">N-1</emphasis> (<emphasis role="bold">
          N
        </emphasis>
        being the number of colors supported
        by your terminal).  This is useful when you remap the colors for your
        display (for example by changing the color associated with <emphasis>
          color2
        </emphasis>
        for your xterm), since color names may then lose their normal meaning.
      </para>
      
      <para>
        If your terminal does not support color, it is still possible change
        the video
        attributes through the use of the ``mono'' command:
      </para>
      
      <para>
        Usage: <literal>mono</literal> <emphasis>&lt;object&gt;
          &lt;attribute&gt;
        </emphasis>
        &lsqb; <emphasis>regexp</emphasis> &rsqb;
        
        Usage: <literal>mono</literal> index <emphasis>attribute</emphasis> <emphasis>
          pattern
        </emphasis>
        
        Usage: <literal>unmono</literal> index <emphasis>pattern</emphasis>
        &lsqb; <emphasis>pattern</emphasis> ...  &rsqb;
        
      </para>
      
      <para>
        where <emphasis>attribute</emphasis> is one of the following:
      </para>
      
      <para>
        
        <itemizedlist>
          <listitem>
            
            <para>
              none
            </para>
          </listitem>
          <listitem>
            
            <para>
              bold
            </para>
          </listitem>
          <listitem>
            
            <para>
              underline
            </para>
          </listitem>
          <listitem>
            
            <para>
              reverse
            </para>
          </listitem>
          <listitem>
            
            <para>
              standout
            </para>
          </listitem>
          
        </itemizedlist>
        
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="ignore">
      <title>Ignoring (weeding) unwanted message headers  </title>
      
      <para>
        Usage: <literal>&lsqb;un&rsqb;ignore</literal> <emphasis>pattern</emphasis> &lsqb; <emphasis>
          pattern
        </emphasis>
        ... &rsqb;
      </para>
      
      <para>
        Messages often have many header fields added by automatic processing
        systems,
        or which may not seem useful to display on the screen.  This command
        allows
        you to specify header fields which you don't normally want to see.
      </para>
      
      <para>
        You do not need to specify the full header field name.  For example,
        ``ignore content-'' will ignore all header fields that begin with the
        pattern
        ``content-''. ``ignore *'' will ignore all headers.
      </para>
      
      <para>
        To remove a previously added token from the list, use the ``unignore''
        command.
        The ``unignore'' command will make Mutt-ng display headers with the
        given pattern.
        For example, if you do ``ignore x-'' it is possible to ``unignore
        x-mailer''.
      </para>
      
      <para>
        ``unignore *'' will remove all tokens from the ignore list.
      </para>
      
      <para>
        For example:
        
        <screen>
# Sven's draconian header weeding
ignore *
unignore from date subject to cc
unignore organization organisation x-mailer: x-newsreader: x-mailing-list:
unignore posted-to:</screen>
        
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="alternates">
      <title>Alternative addresses  </title>
      
      <para>
        Usage: <literal>&lsqb;un&rsqb;alternates</literal> <emphasis>regexp</emphasis> &lsqb; <emphasis>
          regexp
        </emphasis>
        ... &rsqb;
        
      </para>
      
      <para>
        With various functions, mutt will treat messages differently,
        depending on whether you sent them or whether you received them from
        someone else.  For instance, when replying to a message that you
        sent to a different party, mutt will automatically suggest to send
        the response to the original message's recipients -- responding to
        yourself won't make much sense in many cases.  (See <link linkend="reply-to">
          reply-to
        </link>
        .)
      </para>
      
      <para>
        Many users receive e-mail under a number of different addresses. To
        fully use mutt's features here, the program must be able to
        recognize what e-mail addresses you receive mail under. That's the
        purpose of the <literal>alternates</literal> command: It takes a list
        of regular
        expressions, each of which can identify an address under which you
        receive e-mail.
      </para>
      
      <para>
        The <literal>unalternates</literal> command can be used to write
        exceptions to
        <literal>alternates</literal> patterns. If an address matches something
        in an
        <literal>alternates</literal> command, but you nonetheless do not think
        it is
        from you, you can list a more precise pattern under an <literal>
          unalternates
        </literal>
        command.
      </para>
      
      <para>
        To remove a regular expression from the <literal>alternates</literal>
        list, use the
        <literal>unalternates</literal> command with exactly the same <emphasis>
          regexp
        </emphasis>
        .
        Likewise, if the <emphasis>regexp</emphasis> for a <literal>alternates</literal> command matches
        an entry on the <literal>unalternates</literal> list, that <literal>
          unalternates
        </literal>
        entry will be removed. If the <emphasis>regexp</emphasis> for <literal>
          unalternates
        </literal>
        is ``*'', <emphasis>all entries</emphasis> on <literal>alternates</literal> will be removed.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1>
      <title>Format = Flowed    </title>
      
      <sect2>
        <title>Introduction      </title>
        
        <para>
          Mutt-ng contains support for so-called <literal>format=flowed</literal> messages.
          In the beginning of email, each message had a fixed line width, and
          it was enough for displaying them on fixed-size terminals. But times
          changed, and nowadays hardly anybody still uses fixed-size terminals:
          more people nowaydays use graphical user interfaces, with dynamically
          resizable windows. This led to the demand of a new email format that
          makes it possible for the email client to make the email look nice
          in a resizable window without breaking quoting levels and creating
          an incompatible email format that can also be displayed nicely on
          old fixed-size terminals.
        </para>
        
        <para>
          For introductory information on <literal>format=flowed</literal>
          messages, see
          <ulink URL="http://www.joeclark.org/ffaq.html">&#60;http://www.joeclark.org/ffaq.html&#62;</ulink>.
        </para>
        
      </sect2>
      
      <sect2>
        <title>Receiving: Display Setup      </title>
        
        <para>
          When you receive emails that are marked as <literal>format=flowed</literal>
          messages, and is formatted correctly, mutt-ng will try to reformat
          the message to optimally fit on your terminal. If you want a fixed
          margin on the right side of your terminal, you can set the
          following:
        </para>
        
        <para>
          
          <screen>
set wrapmargin = 10</screen>
          
        </para>
        
        <para>
          The code above makes the line break 10 columns before the right
          side of the terminal.
        </para>
        
        <para>
          If your terminal is so wide that the lines are embarrassingly long,
          you can also set a maximum line length:
        </para>
        
        <para>
          
          <screen>
set max_line_length = 120</screen>
          
        </para>
        
        <para>
          The example above will give you lines not longer than 120
          characters.
        </para>
        
        <para>
          When you view at <literal>format=flowed</literal> messages, you will
          often see
          the quoting hierarchy like in the following example:
        </para>
        
        <para>
          
          <screen>
&gt;Bill, can you please send last month's progress report to Mr. 
&gt;Morgan? We also urgently need the cost estimation for the new 
&gt;production server that we want to set up before our customer's 
&gt;project will go live.</screen>
          
        </para>
        
        <para>
          This obviously doesn't look very nice, and it makes it very
          hard to differentiate between text and quoting character. The
          solution is to configure mutt-ng to "stuff" the quoting:
        </para>
        
        <para>
          
          <screen>
set stuff_quoted</screen>
          
        </para>
        
        <para>
          This will lead to a nicer result that is easier to read:
        </para>
        
        <para>
          
          <screen>
&gt; Bill, can you please send last month's progress report to Mr. 
&gt; Morgan? We also urgently need the cost estimation for the new 
&gt; production server that we want to set up before our customer's
&gt; project will go live.</screen>
          
        </para>
        
      </sect2>
      
      <sect2>
        <title>Sending      </title>
        
        <para>
          If you want mutt-ng to send emails with <literal>format=flowed</literal> set, you
          need to explicitly set it:
        </para>
        
        <para>
          
          <screen>
set text_flowed</screen>
          
        </para>
        
        <para>
          Additionally, you have to use an editor which supports writing
          <literal>format=flowed</literal>-conforming emails. For vim, this is
          done by
          adding <literal>w</literal> to the formatoptions (see <literal>:h
            formatoptions
          </literal>
          and
          <literal>:h fo-table</literal>) when writing emails.
        </para>
        
        <para>
          Also note that <emphasis>format=flowed</emphasis> knows about
          ``space-stuffing'',
          that is, when sending messages, some kinds of lines have to be
          indented with a single space on the sending side. On the receiving
          side, the first space (if any) is removed. As a consequence and in
          addition to the above simple setting, please keep this in mind when
          making manual formattings within the editor. Also note that mutt-ng
          currently violates the standard (RfC 3676) as it does not
          space-stuff lines starting with:
        </para>
        
        <para>
          
          <itemizedlist>
            <listitem>
              
              <para>
                <literal>&gt;</literal> This is <emphasis>not</emphasis> the
                quote character but a right
                angle used for other reasons
                
              </para>
            </listitem>
            <listitem>
              
              <para>
                <literal>From</literal> with a trailing space.
                
              </para>
            </listitem>
            <listitem>
              
              <para>
                just a space for formatting reasons
                
              </para>
            </listitem>
            
          </itemizedlist>
          
        </para>
        
        <para>
          Please make sure that you manually prepend a space to each of them.
        </para>
        
      </sect2>
      
      <sect2>
        <title>Additional Notes</title>
        
        <para>
          For completeness, the <link linkend="delete-space">delete-space</link> variable provides the mechanism
          to generate a <literal>DelSp=yes</literal> parameter on <emphasis>
            outgoing
          </emphasis>
          messages.
          According to the standard, clients receiving a <literal>format=flowed</literal>
          messages should delete the last space of a flowed line but still
          interpret the line as flowed. Because flowed lines usually contain
          only one space at the end, this parameter would make the receiving
          client concatenate the last word of the previous with the first of
          the current line <emphasis>without</emphasis> a space. This makes
          ordinary text
          unreadable and is intended for languages rarely using spaces. So
          please use this setting only if you're sure what you're doing.
        </para>
        
        <para>
          
        </para>
        
      </sect2>
      
    </sect1>
    
    <sect1 id="lists">
      <title>Mailing lists  </title>
      
      <para>
        Usage: <literal>&lsqb;un&rsqb;lists</literal> <emphasis>regexp</emphasis> &lsqb; <emphasis>
          regexp
        </emphasis>
        ... &rsqb;
        
        Usage: <literal>&lsqb;un&rsqb;subscribe</literal> <emphasis>regexp</emphasis> &lsqb; <emphasis>
          regexp
        </emphasis>
        ... &rsqb;
      </para>
      
      <para>
        Mutt-ng has a few nice features for <link linkend="using-lists">
          using-lists
        </link>
        .In order to take advantage of them, you must
        specify which addresses belong to mailing lists, and which mailing
        lists you are subscribed to.  Once you have done this, the <link linkend="func-list-reply">
          list-reply
        </link>
        function will work for all known lists.
        Additionally, when you send a message to a subscribed list, mutt will
        add a Mail-Followup-To header to tell other users' mail user agents
        not to send copies of replies to your personal address.   Note that
        the Mail-Followup-To header is a non-standard extension which is not
        supported by all mail user agents.  Adding it is not bullet-proof
        against
        receiving personal CCs of list messages.  Also note that the generation
        of the Mail-Followup-To header is controlled by the <link linkend="followup-to">
          followup-to
        </link>
        configuration variable.
      </para>
      
      <para>
        More precisely, Mutt-ng maintains lists of patterns for the addresses
        of known and subscribed mailing lists.  Every subscribed mailing
        list is known. To mark a mailing list as known, use the ``lists''
        command.  To mark it as subscribed, use ``subscribe''.
      </para>
      
      <para>
        You can use regular expressions with both commands.  To mark all
        messages sent to a specific bug report's address on mutt's bug
        tracking system as list mail, for instance, you could say
        ``subscribe &lsqb;0-9]*@bugs.guug.de''.  Often, it's sufficient to just
        give a portion of the list's e-mail address.
      </para>
      
      <para>
        Specify as much of the address as you need to to remove ambiguity.  For
        example, if you've subscribed to the Mutt-ng mailing list, you will
        receive mail
        addressed to <emphasis>mutt-users@mutt.org</emphasis>.  So, to tell
        Mutt-ng that this is a
        mailing list, you could add ``lists mutt-users'' to your
        initialization file.  To tell mutt that you are subscribed to it,
        add ``subscribe mutt-users'' to your initialization file instead.
        If you also happen to get mail from someone whose address is
        <emphasis>mutt-users@example.com</emphasis>, you could use ``lists
        mutt-users@mutt&bsol;&bsol;.org'' 
        or ``subscribe mutt-users@mutt&bsol;&bsol;.org'' to
        match only mail from the actual list.
      </para>
      
      <para>
        The ``unlists'' command is used to remove a token from the list of
        known and subscribed mailing-lists. Use ``unlists *'' to remove all
        tokens.
      </para>
      
      <para>
        To remove a mailing list from the list of subscribed mailing lists,
        but keep it on the list of known mailing lists, use ``unsubscribe''.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="mbox-hook">
      <title>Using Multiple spool mailboxes  </title>
      
      <para>
        Usage: <literal>mbox-hook</literal> &lsqb;!&rsqb;<emphasis>pattern</emphasis> <emphasis>
          mailbox
        </emphasis>
      </para>
      
      <para>
        This command is used to move read messages from a specified mailbox to
        adifferent mailbox automatically when you quit or change folders.
        <emphasis>pattern</emphasis> is a regular expression specifying the
        mailbox to treat as a
        ``spool'' mailbox and <emphasis>mailbox</emphasis> specifies where mail
        should be saved when
        read.
      </para>
      
      <para>
        Unlike some of the other <emphasis>hook</emphasis> commands, only the <emphasis>
          first
        </emphasis>
        matching
        pattern is used (it is not possible to save read mail in more than a
        single
        mailbox).
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="mailboxes">
      <title>Defining mailboxes which receive mail  </title>
      
      <para>
        Usage: <literal>&lsqb;un&rsqb;mailboxes</literal> &lsqb;!&rsqb;<emphasis>
          filename
        </emphasis>
        &lsqb; <emphasis>filename</emphasis> ... &rsqb;
      </para>
      
      <para>
        This command specifies folders which can receive mail and
        which will be checked for new messages.  By default, the
        main menu status bar displays how many of these folders have
        new messages.
      </para>
      
      <para>
        When changing folders, pressing <emphasis>space</emphasis> will cycle
        through folders with new mail.
      </para>
      
      <para>
        Pressing TAB in the directory browser will bring up a menu showing the
        files
        specified by the <literal>mailboxes</literal> command, and indicate
        which contain new
        messages.  Mutt-ng will automatically enter this mode when invoked from
        the
        command line with the <literal>-y</literal> option.
      </para>
      
      <para>
        The ``unmailboxes'' command is used to remove a token from the list
        of folders which receive mail. Use ``unmailboxes *'' to remove all
        tokens.
      </para>
      
      <para>
        <emphasis role="bold">Note:</emphasis> new mail is detected by
        comparing the last modification time to
        the last access time.  Utilities like <literal>biff</literal> or <literal>
          frm
        </literal>
        or any other
        program which accesses the mailbox might cause Mutt-ng to never detect
        new mail
        for that mailbox if they do not properly reset the access time.  Backup
        tools are another common reason for updated access times.
      </para>
      
      <para>
        <emphasis role="bold">Note:</emphasis> the filenames in the <literal>
          mailboxes
        </literal>
        command are resolved when
        the command is executed, so if these names contain <link linkend="shortcuts">
          shortcuts
        </link>
        (such as ``='' and ``!''), any variable
        definition that affect these characters (like <link linkend="folder">
          folder
        </link>
        and <link linkend="spoolfile">spoolfile</link>)
        should be executed before the <literal>mailboxes</literal> command.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="my-hdr">
      <title>User defined headers  </title>
      
      <para>
        Usage:
        
        <literal>my&lowbar;hdr</literal> <emphasis>string</emphasis>
        
        <literal>unmy&lowbar;hdr</literal> <emphasis>field</emphasis> &lsqb; <emphasis>
          field
        </emphasis>
        ... &rsqb;
      </para>
      
      <para>
        The ``my&lowbar;hdr'' command allows you to create your own header
        fields which will be added to every message you send.
      </para>
      
      <para>
        For example, if you would like to add an ``Organization:'' header field
        to
        all of your outgoing messages, you can put the command
      </para>
      
      <para>
        <screen>
my&lowbar;hdr Organization: A Really Big Company, Anytown, USA</screen>
      </para>
      
      <para>
        in your <literal>.muttrc</literal>.
      </para>
      
      <para>
        <emphasis role="bold">Note:</emphasis>  space characters are <emphasis>
          not
        </emphasis>
        allowed between the keyword and
        the colon (``:'').  The standard for electronic mail (RFC822) says that
        space is illegal there, so Mutt-ng enforces the rule.
      </para>
      
      <para>
        If you would like to add a header field to a single message, you should
        either set the <link linkend="edit-headers">edit-headers</link>
        variable,
        or use the <emphasis>edit-headers</emphasis> function (default: ``E'')
        in the send-menu so
        that you can edit the header of your message along with the body.
      </para>
      
      <para>
        To remove user defined header fields, use the ``unmy&lowbar;hdr''
        command.  You may specify an asterisk (``*'') to remove all header
        fields, or the fields to remove.  For example, to remove all ``To'' and
        ``Cc'' header fields, you could use:
      </para>
      
      <para>
        <screen>
unmy&lowbar;hdr to cc</screen>
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="hdr-order">
      <title>Defining the order of headers when viewing messages  </title>
      
      <para>
        Usage: <literal>hdr&lowbar;order</literal> <emphasis>header1</emphasis>
        <emphasis>header2</emphasis> <emphasis>header3</emphasis>
      </para>
      
      <para>
        With this command, you can specify an order in which mutt will attempt
        to present headers to you when viewing messages.
      </para>
      
      <para>
        ``unhdr&lowbar;order *'' will clear all previous headers from the order
        list,
        thus removing the header order effects set by the system-wide startup
        file.
      </para>
      
      <para>
        
        <screen>
hdr&lowbar;order From Date: From: To: Cc: Subject:</screen>
        
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="save-hook">
      <title>Specify default save filename  </title>
      
      <para>
        Usage: <literal>save-hook</literal> &lsqb;!&rsqb;<emphasis>pattern</emphasis> <emphasis>
          filename
        </emphasis>
      </para>
      
      <para>
        This command is used to override the default filename used when saving
        messages.  <emphasis>filename</emphasis> will be used as the default
        filename if the message is
        <emphasis>From:</emphasis> an address matching <emphasis>regexp</emphasis> or if you are the author and the
        message is addressed <emphasis>to:</emphasis> something matching <emphasis>
          regexp
        </emphasis>
        .
      </para>
      
      <para>
        See <link linkend="pattern-hook">pattern-hook</link> for information on
        the exact format of <emphasis>pattern</emphasis>.
      </para>
      
      <para>
        Examples:
      </para>
      
      <para>
        
        <screen>
save-hook me@(turing\\.)?cs\\.hmc\\.edu$ +elkins
save-hook aol\\.com$ +spam</screen>
        
      </para>
      
      <para>
        Also see the <link linkend="fcc-save-hook">fcc-save-hook</link>
        command.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="fcc-hook">
      <title>Specify default Fcc: mailbox when composing  </title>
      
      <para>
        Usage: <literal>fcc-hook</literal> &lsqb;!&rsqb;<emphasis>pattern</emphasis> <emphasis>
          mailbox
        </emphasis>
      </para>
      
      <para>
        This command is used to save outgoing mail in a mailbox other than
        <link linkend="record">record</link>.  Mutt-ng searches the initial
        list of
        message recipients for the first matching <emphasis>regexp</emphasis>
        and uses <emphasis>mailbox</emphasis>
        as the default Fcc: mailbox.  If no match is found the message will be
        saved
        to <link linkend="record">record</link> mailbox.
      </para>
      
      <para>
        See <link linkend="pattern-hook">pattern-hook</link> for information on
        the exact format of <emphasis>pattern</emphasis>.
      </para>
      
      <para>
        Example: <literal>fcc-hook &lsqb;@.&rsqb;aol&bsol;&bsol;.com&dollar;
          +spammers
        </literal>
      </para>
      
      <para>
        The above will save a copy of all messages going to the aol.com domain
        to
        the `+spammers' mailbox by default.  Also see the <link linkend="fcc-save-hook">
          fcc-save-hook
        </link>
        command.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="fcc-save-hook">
      <title>Specify default save filename and default Fcc: mailbox at once  </title>
      
      <para>
        Usage: <literal>fcc-save-hook</literal> &lsqb;!&rsqb;<emphasis>pattern</emphasis> <emphasis>
          mailbox
        </emphasis>
      </para>
      
      <para>
        This command is a shortcut, equivalent to doing both a <link linkend="fcc-hook">
          fcc-hook
        </link>
        and a <link linkend="save-hook">save-hook</link> with its arguments.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="send-hook">
      <title>Change settings based upon message recipients  </title>
      
      <para>
        Usage: <literal>reply-hook</literal> &lsqb;!&rsqb;<emphasis>pattern</emphasis> <emphasis>
          command
        </emphasis>
        
        Usage: <literal>send-hook</literal> &lsqb;!&rsqb;<emphasis>pattern</emphasis> <emphasis>
          command
        </emphasis>
        
        Usage: <literal>send2-hook</literal> &lsqb;!&rsqb;<emphasis>pattern</emphasis> <emphasis>
          command
        </emphasis>
      </para>
      
      <para>
        These commands can be used to execute arbitrary configuration commands
        based
        upon recipients of the message.  <emphasis>pattern</emphasis> is a
        regular expression
        matching the desired address.  <emphasis>command</emphasis> is executed
        when <emphasis>regexp</emphasis>
        matches recipients of the message.
      </para>
      
      <para>
        <literal>reply-hook</literal> is matched against the message you are <emphasis>
          replying
        </emphasis>
        <emphasis role="bold">to</emphasis>, instead of the message you are <emphasis>
          sending
        </emphasis>
        .<literal>send-hook</literal> is
        matched against all messages, both <emphasis>new</emphasis> and <emphasis>
          replies
        </emphasis>
        .<emphasis role="bold">Note:</emphasis>
        <literal>reply-hook</literal>s are matched <emphasis role="bold">before</emphasis> the <literal>
          send-hook
        </literal>
        ,<emphasis role="bold">regardless</emphasis>
        of the order specified in the users's configuration file.
      </para>
      
      <para>
        <literal>send2-hook</literal> is matched every time a message is
        changed, either
        by editing it, or by using the compose menu to change its recipients
        or subject.  <literal>send2-hook</literal> is executed after <literal>
          send-hook
        </literal>
        ,and
        can, e.g., be used to set parameters such as the <link linkend="sendmail">
          sendmail
        </link>
        variable depending on the message's sender
        address.
      </para>
      
      <para>
        For each type of <literal>send-hook</literal> or <literal>reply-hook</literal>, when multiple matches
        occur, commands are executed in the order they are specified in the
        muttrc
        (for that type of hook).
      </para>
      
      <para>
        See <link linkend="pattern-hook">pattern-hook</link> for information on
        the exact format of <emphasis>pattern</emphasis>.
      </para>
      
      <para>
        Example: <literal>send-hook mutt &quot;set mime&lowbar;forward
          signature=''&quot;
        </literal>
      </para>
      
      <para>
        Another typical use for this command is to change the values of the
        <link linkend="attribution">attribution</link>, <link linkend="signature">
          signature
        </link>
        and <link linkend="locale">locale</link>
        variables in order to change the language of the attributions and
        signatures based upon the recipients.
      </para>
      
      <para>
        <emphasis role="bold">Note:</emphasis> the send-hook's are only
        executed ONCE after getting the initial
        list of recipients.  Adding a recipient after replying or editing the
        message will NOT cause any send-hook to be executed.  Also note that
        my&lowbar;hdr commands which modify recipient headers, or the message's
        subject, don't have any effect on the current message when executed
        from a send-hook.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="message-hook">
      <title>Change settings before formatting a message  </title>
      
      <para>
        Usage: <literal>message-hook</literal> &lsqb;!&rsqb;<emphasis>pattern</emphasis> <emphasis>
          command
        </emphasis>
      </para>
      
      <para>
        This command can be used to execute arbitrary configuration commands
        before viewing or formatting a message based upon information about the
        message.
        <emphasis>command</emphasis> is executed if the <emphasis>pattern</emphasis> matches the message to be
        displayed. When multiple matches occur, commands are executed in the
        order
        they are specified in the muttrc.
      </para>
      
      <para>
        See <link linkend="pattern-hook">pattern-hook</link> for
        information on the exact format of <emphasis>pattern</emphasis>.
      </para>
      
      <para>
        Example:
        
        <screen>
message-hook ~A 'set pager=builtin'
message-hook '~f freshmeat-news' 'set pager="less \"+/^  subject:.*\""'</screen>
        
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="crypt-hook">
      <title>Choosing the cryptographic key of the recipient  </title>
      
      <para>
        Usage: <literal>crypt-hook</literal> <emphasis>pattern</emphasis> <emphasis>
          keyid
        </emphasis>
      </para>
      
      <para>
        When encrypting messages with PGP or OpenSSL, you may want to associate
        a certain
        key with a given e-mail address automatically, either because the
        recipient's public key can't be deduced from the destination address,
        or because, for some reasons, you need to override the key Mutt-ng
        wouldnormally use.  The crypt-hook command provides a method by which
        you can
        specify the ID of the public key to be used when encrypting messages to
        a certain recipient.
      </para>
      
      <para>
        The meaning of "key id" is to be taken broadly in this context:  You
        can either put a numerical key ID here, an e-mail address, or even
        just a real name.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="push">
      <title>Adding key sequences to the keyboard buffer  </title>
      
      <para>
        Usage: <literal>push</literal> <emphasis>string</emphasis>
      </para>
      
      <para>
        This command adds the named string to the keyboard buffer. The string
        may
        contain control characters, key names and function names like the
        sequence
        string in the <link linkend="macro">macro</link> command. You may use
        it to
        automatically run a sequence of commands at startup, or when entering
        certain folders.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="exec">
      <title>Executing functions  </title>
      
      <para>
        Usage: <literal>exec</literal> <emphasis>function</emphasis> &lsqb; <emphasis>
          function
        </emphasis>
        ... &rsqb;
      </para>
      
      <para>
        This command can be used to execute any function. Functions are
        listed in the <link linkend="functions">functions</link>.
        ``exec function'' is equivalent to ``push &lt;function&gt;''.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="score-command">
      <title>Message Scoring  </title>
      
      <para>
        Usage: <literal>score</literal> <emphasis>pattern</emphasis> <emphasis>
          value
        </emphasis>
        
        Usage: <literal>unscore</literal> <emphasis>pattern</emphasis> &lsqb; <emphasis>
          pattern
        </emphasis>
        ... &rsqb;
      </para>
      
      <para>
        In situations where you have to cope with a lot of emails, e.g.
        when you read many different mailing lists, and take part in
        discussions, it is always useful to have the important messages
        marked and the annoying messages or the ones that you aren't
        interested in deleted. For this purpose, mutt-ng features a
        mechanism called ``scoring''.
      </para>
      
      <para>
        When you use scoring, every message has a base score of 0. You
        can then use the <literal>score</literal> command to define patterns
        and a
        positive or negative value associated with it. When a pattern
        matches a message, the message's score will be raised or lowered by
        the amount of the value associated with the pattern.
      </para>
      
      <para>
        
        <screen>
score "~f nion@muttng\.org" 50
score "~f @sco\.com" -100</screen>
        
      </para>
      
      <para>
        If the pattern matches, it is also possible to set the score
        value of the current message to a certain value and then stop
        evaluation:
      </para>
      
      <para>
        
        <screen>
score "~f santaclaus@northpole\.int" =666</screen>
        
      </para>
      
      <para>
        What is important to note is that negative score values will be
        rounded up to 0.
      </para>
      
      <para>
        To make scoring actually useful, the score must be applied in
        some way.  That's what the <emphasis>score thresholds</emphasis> are
        for. Currently,
        there are three score thresholds:
      </para>
      
      <para>
        
        <itemizedlist>
          <listitem>
            
            <para>
              flag threshold: when a message has a score value equal or higher
              than the flag threshold, it will be flagged.
              
            </para>
          </listitem>
          <listitem>
            
            <para>
              read threshold: when a message has a score value equal or lower
              than the read threshold, it will be marked as read.
              
            </para>
          </listitem>
          <listitem>
            
            <para>
              delete threshold: when a message has a score value equal or
              lower than the delete threshold, it will be marked as deleted.
              
            </para>
          </listitem>
          
        </itemizedlist>
        
      </para>
      
      <para>
        These three thresholds can be set via the variables <link linkend="score-threshold-flag">
          score-threshold-flag
        </link>
        ,<link linkend="score-threshold-read">score-threshold-read</link>, <link linkend="score-threshold-delete">
          score-threshold-delete
        </link>
        and.  By
        default, <link linkend="score-threshold-read">score-threshold-read</link> and <link linkend="score-threshold-delete">
          score-threshold-delete
        </link>
        are set to
        <literal>-1</literal>, which means that in the default threshold
        configuration no
        message will ever get marked as read or deleted.
      </para>
      
      <para>
        Scoring gets especially interesting when combined with the <literal>
          color
        </literal>
        command
        and the <literal>&tilde;n</literal> pattern:
      </para>
      
      <para>
        
        <screen>
color index  black   yellow  "~n 10-"
color index  red     yellow  "~n 100-"</screen>
        
      </para>
      
      <para>
        The rules above mark all messages with a score between 10 and 99
        with black and yellow, and messages with a score greater or equal
        100 with red and yellow. This might be unusual to you if you're used
        to e.g. slrn's scoring mechanism, but it is more flexible, as it
        visually marks different scores.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="spam">
      <title>Spam detection  </title>
      
      <para>
        Usage: <literal>spam</literal> <emphasis>pattern</emphasis> <emphasis>
          format
        </emphasis>
        
        Usage: <literal>nospam</literal> <emphasis>pattern</emphasis>
      </para>
      
      <para>
        Mutt-ng has generalized support for external spam-scoring filters.
        By defining your spam patterns with the <literal>spam</literal> and <literal>
          nospam
        </literal>
        commands, you can <emphasis>limit</emphasis>, <emphasis>search</emphasis>, and <emphasis>
          sort
        </emphasis>
        your
        mail based on its spam attributes, as determined by the external
        filter. You also can display the spam attributes in your index
        display using the <literal>&percnt;H</literal> selector in the <link linkend="index-format">
          index-format
        </link>
        variable. (Tip: try <literal>&percnt;?H?[&percnt;H] ?</literal>
        to display spam tags only when they are defined for a given message.)
      </para>
      
      <para>
        Your first step is to define your external filter's spam patterns using
        the <literal>spam</literal> command. <emphasis>pattern</emphasis>
        should be a regular expression
        that matches a header in a mail message. If any message in the mailbox
        matches this regular expression, it will receive a ``spam tag'' or
        ``spam attribute'' (unless it also matches a <literal>nospam</literal>
        pattern -- see
        below.) The appearance of this attribute is entirely up to you, and is
        governed by the <emphasis>format</emphasis> parameter. <emphasis>format</emphasis> can be any static
        text, but it also can include back-references from the <emphasis>
          pattern
        </emphasis>
        expression. (A regular expression ``back-reference'' refers to a
        sub-expression contained within parentheses.) <literal>&percnt;1</literal> is replaced with
        the first back-reference in the regex, <literal>&percnt;2</literal>
        with the second, etc.
      </para>
      
      <para>
        If you're using multiple spam filters, a message can have more than
        one spam-related header. You can define <literal>spam</literal>
        patterns for each
        filter you use. If a message matches two or more of these patterns, and
        the &dollar;spam&lowbar;separator variable is set to a string, then the
        message's spam tag will consist of all the <emphasis>format</emphasis>
        strings joined
        together, with the value of &dollar;spam&lowbar;separator separating
        them.
      </para>
      
      <para>
        For example, suppose I use DCC, SpamAssassin, and PureMessage. I might
        define these spam settings:
        
        <screen>
spam "X-DCC-.*-Metrics:.*(....)=many"         "90+/DCC-%1"
spam "X-Spam-Status: Yes"                     "90+/SA"
spam "X-PerlMX-Spam: .*Probability=([0-9]+)%" "%1/PM"
set spam_separator=", "</screen>
        
      </para>
      
      <para>
        If I then received a message that DCC registered with ``many'' hits
        under the ``Fuz2'' checksum, and that PureMessage registered with a
        97&percnt; probability of being spam, that message's spam tag would
        read<literal>90+/DCC-Fuz2, 97/PM</literal>. (The four characters before
        ``=many'' in a
        DCC report indicate the checksum used -- in this case, ``Fuz2''.)
      </para>
      
      <para>
        If the &dollar;spam&lowbar;separator variable is unset, then each
        spam pattern match supersedes the previous one. Instead of getting
        joined <emphasis>format</emphasis> strings, you'll get only the last
        one to match.
      </para>
      
      <para>
        The spam tag is what will be displayed in the index when you use
        <literal>&percnt;H</literal> in the <literal>
          &dollar;index&lowbar;format
        </literal>
        variable. It's also the
        string that the <literal>&tilde;H</literal> pattern-matching expression
        matches against for
        <emphasis>search</emphasis> and <emphasis>limit</emphasis> functions.
        And it's what sorting by spam
        attribute will use as a sort key.
      </para>
      
      <para>
        That's a pretty complicated example, and most people's actual
        environments will have only one spam filter. The simpler your
        configuration, the more effective mutt can be, especially when it comes
        to sorting.
      </para>
      
      <para>
        Generally, when you sort by spam tag, mutt will sort <emphasis>
          lexically
        </emphasis>
        --
        that is, by ordering strings alphnumerically. However, if a spam tag
        begins with a number, mutt will sort numerically first, and lexically
        only when two numbers are equal in value. (This is like UNIX's
        <literal>sort -n</literal>.) A message with no spam attributes at all
        -- that is, one
        that didn't match <emphasis>any</emphasis> of your <literal>spam</literal> patterns -- is sorted at
        lowest priority. Numbers are sorted next, beginning with 0 and ranging
        upward. Finally, non-numeric strings are sorted, with ``a'' taking
        lowerpriority than ``z''. Clearly, in general, sorting by spam tags is
        most
        effective when you can coerce your filter to give you a raw number. But
        in case you can't, mutt can still do something useful.
      </para>
      
      <para>
        The <literal>nospam</literal> command can be used to write exceptions
        to <literal>spam</literal>
        patterns. If a header pattern matches something in a <literal>spam</literal> command,
        but you nonetheless do not want it to receive a spam tag, you can list
        amore precise pattern under a <literal>nospam</literal> command.
      </para>
      
      <para>
        If the <emphasis>pattern</emphasis> given to <literal>nospam</literal>
        is exactly the same as the
        <emphasis>pattern</emphasis> on an existing <literal>spam</literal>
        list entry, the effect will be to
        remove the entry from the spam list, instead of adding an exception.
        Likewise, if the <emphasis>pattern</emphasis> for a <literal>spam</literal> command matches an entry
        on the <literal>nospam</literal> list, that <literal>nospam</literal>
        entry will be removed. If the
        <emphasis>pattern</emphasis> for <literal>nospam</literal> is ``*'', <emphasis>
          all entries on both lists
        </emphasis>
        will be removed. This might be the default action if you use <literal>
          spam
        </literal>
        and <literal>nospam</literal> in conjunction with a <literal>
          folder-hook
        </literal>
        .
      </para>
      
      <para>
        You can have as many <literal>spam</literal> or <literal>nospam</literal> commands as you like.
        You can even do your own primitive spam detection within mutt -- for
        example, if you consider all mail from <literal>MAILER-DAEMON</literal>
        to be spam,
        you can use a <literal>spam</literal> command like this:
      </para>
      
      <para>
        
        <screen>
spam "^From: .*MAILER-DAEMON"       "999"</screen>
        
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="set">
      <title>Setting variables  </title>
      
      <para>
        Usage: <literal>set</literal> &lsqb;no&verbar;inv&rsqb;<emphasis>
          variable
        </emphasis>
        &lsqb;=<emphasis>value</emphasis>&rsqb; &lsqb; <emphasis>variable</emphasis> ... &rsqb;
        
        Usage: <literal>toggle</literal> <emphasis>variable</emphasis> &lsqb;<emphasis>
          variable
        </emphasis>
        ... &rsqb;
        
        Usage: <literal>unset</literal> <emphasis>variable</emphasis> &lsqb;<emphasis>
          variable
        </emphasis>
        ... &rsqb;
        
        Usage: <literal>reset</literal> <emphasis>variable</emphasis> &lsqb;<emphasis>
          variable
        </emphasis>
        ... &rsqb;
      </para>
      
      <para>
        This command is used to set (and unset) <link linkend="variables">
          variables
        </link>
        .There are four basic types of variables:
        boolean, number, string and quadoption.  <emphasis>boolean</emphasis>
        variables can be
        <emphasis>set</emphasis> (true) or <emphasis>unset</emphasis> (false). 
        <emphasis>number</emphasis> variables can be
        assigned a positive integer value.
      </para>
      
      <para>
        <emphasis>string</emphasis> variables consist of any number of
        printable characters.
        <emphasis>strings</emphasis> must be enclosed in quotes if they contain
        spaces or tabs.  You
        may also use the ``C'' escape sequences <emphasis role="bold">&bsol;n</emphasis> and <emphasis role="bold">
          &bsol;t
        </emphasis>
        for
        newline and tab, respectively.
      </para>
      
      <para>
        <emphasis>quadoption</emphasis> variables are used to control whether
        or not to be prompted
        for certain actions, or to specify a default action.  A value of <emphasis>
          yes
        </emphasis>
        will cause the action to be carried out automatically as if you had
        answered
        yes to the question.  Similarly, a value of <emphasis>no</emphasis>
        will cause the the
        action to be carried out as if you had answered ``no.''  A value of
        <emphasis>ask-yes</emphasis> will cause a prompt with a default answer
        of ``yes'' and
        <emphasis>ask-no</emphasis> will provide a default answer of ``no.''
      </para>
      
      <para>
        Prefixing a variable with ``no'' will unset it.  Example: <literal>set
          noaskbcc
        </literal>
        .
      </para>
      
      <para>
        For <emphasis>boolean</emphasis> variables, you may optionally prefix
        the variable name with
        <literal>inv</literal> to toggle the value (on or off).  This is useful
        when writing
        macros.  Example: <literal>set invsmart&lowbar;wrap</literal>.
      </para>
      
      <para>
        The <literal>toggle</literal> command automatically prepends the <literal>
          inv
        </literal>
        prefix to all
        specified variables.
      </para>
      
      <para>
        The <literal>unset</literal> command automatically prepends the <literal>
          no
        </literal>
        prefix to all
        specified variables.
      </para>
      
      <para>
        Using the enter-command function in the <emphasis>index</emphasis>
        menu, you can query the
        value of a variable by prefixing the name of the variable with a
        question
        mark:
      </para>
      
      <para>
        
        <screen>
set ?allow_8bit</screen>
        
      </para>
      
      <para>
        The question mark is actually only required for boolean and quadoption 
        variables.
      </para>
      
      <para>
        The <literal>reset</literal> command resets all given variables to the
        compile time
        defaults (hopefully mentioned in this manual). If you use the command
        <literal>set</literal> and prefix the variable with ``&amp;'' this has
        the same
        behavior as the reset command.
      </para>
      
      <para>
        With the <literal>reset</literal> command there exists the special
        variable ``all'',
        which allows you to reset all variables to their system defaults.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="source">
      <title>Reading initialization commands from another file  </title>
      
      <para>
        Usage: <literal>source</literal> <emphasis>filename</emphasis> &lsqb; <emphasis>
          filename
        </emphasis>
        ... &rsqb;
      </para>
      
      <para>
        This command allows the inclusion of initialization commands
        from other files.  For example, I place all of my aliases in
        <literal>&tilde;/.mail&lowbar;aliases</literal> so that I can make my
        <literal>&tilde;/.muttrc</literal> readable and keep my aliases
        private.
      </para>
      
      <para>
        If the filename begins with a tilde (``&tilde;''), it will be expanded
        to the
        path of your home directory.
      </para>
      
      <para>
        If the filename ends with a vertical bar (&verbar;), then <emphasis>
          filename
        </emphasis>
        is
        considered to be an executable program from which to read input (eg.
        <literal>source &tilde;/bin/myscript&verbar;</literal>).
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="unhook">
      <title>Removing hooks  </title>
      
      <para>
        Usage: <literal>unhook</literal> &lsqb; * &verbar; <emphasis>hook-type</emphasis> &rsqb;
      </para>
      
      <para>
        This command permits you to flush hooks you have previously defined.
        You can either remove all hooks by giving the ``*'' character as an
        argument, or you can remove all hooks of a specific type by saying
        something like <literal>unhook send-hook</literal>.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="sect:sharingsetups">
      <title>Sharing Setups      </title>
      
      <sect2>
        <title>Character Sets      </title>
        
        <para>
          As users may run mutt-ng on different systems, the configuration
          must be maintained because it's likely that people want to use the
          setup everywhere they use mutt-ng. And mutt-ng tries to help where it
          can.
        </para>
        
        <para>
          To not produce conflicts with different character sets, mutt-ng
          allows users to specify in which character set their configuration
          files are encoded. Please note that while reading the configuration
          files, this is only respected after the corresponding declaration
          appears. It's advised to put the following at the very beginning of a
          users muttngrc:
        </para>
        
        <para>
          
          <screen>
set config_charset = "..."</screen>
          
        </para>
        
        <para>
          and replacing the dots with the actual character set. To avoid
          problems while maintaining the setup, vim user's may want to use
          modelines as show in:
        </para>
        
        <para>
          
          <screen>
# vim:fileencoding=...:</screen>
          
        </para>
        
        <para>
          while, again, replacing the dots with the appropriate name. This
          tells vim as which character set to read and save the file.
        </para>
        
        <para>
          
        </para>
        
      </sect2>
      
      <sect2>
        <title>Modularization        </title>
        
        <para>
          ``Modularization'' means to divide the setup into several files
          while sorting the options or commands by topic. Especially for
          longer setups (e.g. with many hooks), this helps maintaining it
          and solving trouble.
        </para>
        
        <para>
          When using separation, setups may be, as a whole or in
          fractions, shared over different systems.
        </para>
        
        <para>
          
        </para>
        
      </sect2>
      
      <sect2>
        <title>Conditional parts      </title>
        
        <para>
          When using a configuration on different systems, the user may not
          always have influence on how mutt-ng is installed and which features
          it includes.
        </para>
        
        <para>
          To solve this, mutt-ng contain a feature based on the ``ifdef''
          patch written for mutt. Its basic syntax is:
        </para>
        
        <para>
          
          <screen>
ifdef &lt;item&gt; &lt;command&gt;
ifndef &lt;item&gt; &lt;command&gt;</screen>
          
        </para>
        
        <para>
          ...whereby <literal>&lt;item&gt;</literal> can be one of:
        </para>
        
        <para>
          
          <itemizedlist>
            <listitem>
              
              <para>
                a function name
                
              </para>
            </listitem>
            <listitem>
              
              <para>
                a variable name
                
              </para>
            </listitem>
            <listitem>
              
              <para>
                a menu name
                
              </para>
            </listitem>
            <listitem>
              
              <para>
                a feature name
                
              </para>
            </listitem>
            
          </itemizedlist>
          
        </para>
        
        <para>
          All available functions, variables and menus are documented
          elsewhere in this manual but ``features'' is specific to these
          two commands. To test for one, prefix one of the following
          keywords with <literal>feature&lowbar;</literal>: ncurses,
          slang, iconv, idn, dotlock, standalone, pop, nntp, imap, ssl,
          gnutls, sasl, sasl2, libesmtp, compressed, color, classic_pgp,
          classic_smime, gpgme, header_cache
        </para>
        
        <para>
          As an example, one can use the following in
          <literal>&tilde;/.muttngrc</literal>:
        </para>
        
        <para>
          
          <screen>
ifdef feature_imap 'source ~/.mutt-ng/setup-imap'
ifdef feature_pop  'source ~/.mutt-ng/setup-pop'
ifdef feature_nntp 'source ~/.mutt-ng/setup-nntp'</screen>
          
        </para>
        
        <para>
          ...to only source <literal>&tilde;/.mutt-ng/setup-imap</literal> if
          IMAP
          support is built in, only source <literal>&tilde;/.mutt-ng/setup-pop</literal>
          if POP support is built in and only source
          <literal>&tilde;/.mutt-ng/setup-nntp</literal> if NNTP support is
          built in.
        </para>
        
        <para>
          An example for testing for variable names can be used if users
          use different revisions of mutt-ng whereby the older one may not
          have a certain variable. To test for the availability of <link linkend="imap-mail-check">
            imap-mail-check
          </link>
          ,
          use:
        </para>
        
        <para>
          
          <screen>
ifdef imap_mail_check 'set imap_mail_check = 300'</screen>
          
        </para>
        
        <para>
          Provided for completeness is the test for menu names. To set <link linkend="pager-index-lines">
            pager-index-lines
          </link>
          only if the pager
          menu is available, use:
        </para>
        
        <para>
          
          <screen>
ifdef pager 'set pager_index_lines = 10'</screen>
          
        </para>
        
        <para>
          For completeness, too, the opposite of <literal>ifdef</literal> is
          provided:
          <literal>ifndef</literal> which only executes the command if the test
          fails. For
          example, the following two examples are equivalent:
        </para>
        
        <para>
          
          <screen>
ifdef feature_ncurses 'source ~/.mutt-ng/setup-ncurses'
ifndef feature_ncurses 'source ~/.mutt-ng/setup-slang'</screen>
          
        </para>
        
        <para>
          ...and...
        </para>
        
        <para>
          
          <screen>
ifdef feature_slang 'source ~/.mutt-ng/setup-slang'
ifndef feature_slang 'source ~/.mutt-ng/setup-ncurses'</screen>
          
        </para>
        
        <para>
          
        </para>
        
        <para>
          
        </para>
        
      </sect2>
      
    </sect1>
    
    <sect1>
      <title>Obsolete Variables  </title>
      
      <para>
        In the process of ensuring and creating more consistency, many
        variables have been renamed and some of the old names were already
        removed. Please see <link linkend="sect-obsolete">sect-obsolete</link>
        for a complete list.
      </para>
      
      <para>
        
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
  </chapter>
  
  <chapter>
    <title>Advanced Usage  </title>
    
    <sect1 id="regexp">
      <title>Regular Expressions  </title>
      
      <para>
        All string patterns in Mutt-ng including those in more complex
        <link linkend="patterns">patterns</link> must be specified
        using regular expressions (regexp) in the ``POSIX extended'' syntax
        (which
        is more or less the syntax used by egrep and GNU awk).  For your
        convenience, we have included below a brief description of this syntax.
      </para>
      
      <para>
        The search is case sensitive if the pattern contains at least one upper
        case letter, and case insensitive otherwise. Note that ``&bsol;''
        must be quoted if used for a regular expression in an initialization
        command: ``&bsol;&bsol;''.
      </para>
      
      <para>
        A regular expression is a pattern that describes a set of strings.
        Regular expressions are constructed analogously to arithmetic
        expressions, by using various operators to combine smaller expressions.
      </para>
      
      <para>
        Note that the regular expression can be enclosed/delimited by either
        &quot;
        or ' which is useful if the regular expression includes a white-space
        character.  See <link linkend="muttrc-syntax">muttrc-syntax</link>
        for more information on &quot; and ' delimiter processing.  To match a
        literal &quot; or ' you must preface it with \ (backslash).
      </para>
      
      <para>
        The fundamental building blocks are the regular expressions that match
        a single character.  Most characters, including all letters and digits,
        are regular expressions that match themselves.  Any metacharacter with
        special meaning may be quoted by preceding it with a backslash.
      </para>
      
      <para>
        The period ``.'' matches any single character.  The caret ``&circ;''
        andthe dollar sign ``&dollar;'' are metacharacters that respectively
        match
        the empty string at the beginning and end of a line.
      </para>
      
      <para>
        A list of characters enclosed by ``&lsqb;'' and ``&rsqb;'' matches any
        single character in that list; if the first character of the list
        is a caret ``&circ;'' then it matches any character <emphasis role="bold">
          not
        </emphasis>
        in the
        list.  For example, the regular expression <emphasis role="bold">
          &lsqb;0123456789&rsqb;
        </emphasis>
        matches any single digit.  A range of ASCII characters may be specified
        by giving the first and last characters, separated by a hyphen
        ``-''.  Most metacharacters lose their special meaning inside
        lists.  To include a literal ``&rsqb;'' place it first in the list.
        Similarly, to include a literal ``&circ;'' place it anywhere but first.
        Finally, to include a literal hyphen ``-'' place it last.
      </para>
      
      <para>
        Certain named classes of characters are predefined.  Character classes
        consist of ``&lsqb;:'', a keyword denoting the class, and ``:&rsqb;''.
        The following classes are defined by the POSIX standard:
      </para>
      
      <para>
        <variablelist>
          
          <varlistentry>
            <term>&lsqb;:alnum:&rsqb;</term>
            <listitem>
              <para>
                Alphanumeric characters.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>&lsqb;:alpha:&rsqb;</term>
            <listitem>
              <para>
                Alphabetic characters.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>&lsqb;:blank:&rsqb;</term>
            <listitem>
              <para>
                Space or tab characters.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>&lsqb;:cntrl:&rsqb;</term>
            <listitem>
              <para>
                Control characters.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>&lsqb;:digit:&rsqb;</term>
            <listitem>
              <para>
                Numeric characters.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>&lsqb;:graph:&rsqb;</term>
            <listitem>
              <para>
                Characters that are both printable and visible.  (A space is
                printable,
                but not visible, while an ``a'' is both.)
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>&lsqb;:lower:&rsqb;</term>
            <listitem>
              <para>
                Lower-case alphabetic characters.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>&lsqb;:print:&rsqb;</term>
            <listitem>
              <para>
                Printable characters (characters that are not control
                characters.)
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>&lsqb;:punct:&rsqb;</term>
            <listitem>
              <para>
                Punctuation characters (characters that are not letter, digits,
                control
                characters, or space characters).
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>&lsqb;:space:&rsqb;</term>
            <listitem>
              <para>
                Space characters (such as space, tab and formfeed, to name a
                few).
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>&lsqb;:upper:&rsqb;</term>
            <listitem>
              <para>
                Upper-case alphabetic characters.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>&lsqb;:xdigit:&rsqb;</term>
            <listitem>
              <para>
                Characters that are hexadecimal digits.
              </para>
            </listitem>
          </varlistentry>
        </variablelist>
      </para>
      
      <para>
        A character class is only valid in a regular expression inside the
        brackets of a character list.  Note that the brackets in these
        class names are part of the symbolic names, and must be included
        in addition to the brackets delimiting the bracket list.  For
        example, <emphasis role="bold">&lsqb;&lsqb;:digit:&rsqb;&rsqb;</emphasis> is equivalent to
        <emphasis role="bold">&lsqb;0-9&rsqb;</emphasis>.
      </para>
      
      <para>
        Two additional special sequences can appear in character lists.  These
        apply to non-ASCII character sets, which can have single symbols
        (calledcollating elements) that are represented with more than one
        character,
        as well as several characters that are equivalent for collating or
        sorting purposes:
      </para>
      
      <para>
        <variablelist>
          
          <varlistentry>
            <term>Collating Symbols</term>
            <listitem>
              <para>
                A collating symbol is a multi-character collating element
                enclosed in
                ``&lsqb;.'' and ``.&rsqb;''.  For example, if ``ch'' is a
                collating
                element, then <emphasis role="bold">
                  &lsqb;&lsqb;.ch.&rsqb;&rsqb;
                </emphasis>
                is a regexp that matches
                this collating element, while <emphasis role="bold">
                  &lsqb;ch&rsqb;
                </emphasis>
                is a regexp that
                matches either ``c'' or ``h''.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>Equivalence Classes</term>
            <listitem>
              <para>
                An equivalence class is a locale-specific name for a list of
                characters that are equivalent. The name is enclosed in
                ``&lsqb;=''
                and ``=&rsqb;''.  For example, the name ``e'' might be used to
                represent all of ``&egrave;'' ``&eacute;'' and ``e''.  In this
                case,
                <emphasis role="bold">&lsqb;&lsqb;=e=&rsqb;&rsqb;</emphasis> is
                a regexp that matches any of
                ``&egrave;'', ``&eacute;'' and ``e''.
              </para>
            </listitem>
          </varlistentry>
        </variablelist>
      </para>
      
      <para>
        A regular expression matching a single character may be followed by one
        of several repetition operators:
      </para>
      
      <para>
        <variablelist>
          
          <varlistentry>
            <term>?</term>
            <listitem>
              <para>
                The preceding item is optional and matched at most once.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>*</term>
            <listitem>
              <para>
                The preceding item will be matched zero or more times.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>+</term>
            <listitem>
              <para>
                The preceding item will be matched one or more times.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>&lcub;n&rcub;</term>
            <listitem>
              <para>
                The preceding item is matched exactly <emphasis>n</emphasis>
                times.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>&lcub;n,&rcub;</term>
            <listitem>
              <para>
                The preceding item is matched <emphasis>n</emphasis> or more
                times.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>&lcub;,m&rcub;</term>
            <listitem>
              <para>
                The preceding item is matched at most <emphasis>m</emphasis>
                times.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>&lcub;n,m&rcub;</term>
            <listitem>
              <para>
                The preceding item is matched at least <emphasis>n</emphasis>
                times, but no more than
                <emphasis>m</emphasis> times.
              </para>
            </listitem>
          </varlistentry>
        </variablelist>
      </para>
      
      <para>
        Two regular expressions may be concatenated; the resulting regular
        expression matches any string formed by concatenating two substrings
        that respectively match the concatenated subexpressions.
      </para>
      
      <para>
        Two regular expressions may be joined by the infix operator
        ``&verbar;'';
        the resulting regular expression matches any string matching either
        subexpression.
      </para>
      
      <para>
        Repetition takes precedence over concatenation, which in turn takes
        precedence over alternation.  A whole subexpression may be enclosed in
        parentheses to override these precedence rules.
      </para>
      
      <para>
        <emphasis role="bold">Note:</emphasis> If you compile Mutt-ng with the
        GNU <emphasis>rx</emphasis> package, the
        following operators may also be used in regular expressions:
      </para>
      
      <para>
        <variablelist>
          
          <varlistentry>
            <term>&bsol;&bsol;y</term>
            <listitem>
              <para>
                Matches the empty string at either the beginning or the end of
                a word.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>&bsol;&bsol;B</term>
            <listitem>
              <para>
                Matches the empty string within a word.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>&bsol;&bsol;&lt;</term>
            <listitem>
              <para>
                Matches the empty string at the beginning of a word.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>&bsol;&bsol;&gt;</term>
            <listitem>
              <para>
                Matches the empty string at the end of a word.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>&bsol;&bsol;w</term>
            <listitem>
              <para>
                Matches any word-constituent character (letter, digit, or
                underscore).
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>&bsol;&bsol;W</term>
            <listitem>
              <para>
                Matches any character that is not word-constituent.
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>&bsol;&bsol;`</term>
            <listitem>
              <para>
                Matches the empty string at the beginning of a buffer (string).
              </para>
            </listitem>
          </varlistentry>
          <varlistentry>
            <term>&bsol;&bsol;'</term>
            <listitem>
              <para>
                Matches the empty string at the end of a buffer.
              </para>
            </listitem>
          </varlistentry>
        </variablelist>
      </para>
      
      <para>
        Please note however that these operators are not defined by POSIX, so
        they may or may not be available in stock libraries on various systems.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1>
      <title>Patterns  </title>
      
      <para>
        Mutt-ng's pattern language provides a simple yet effective way to
        set up rules to match messages, e.g. for operations like tagging and
        scoring. A pattern consists of one or more sub-pattern, which can be
        logically grouped, ORed, and negated. For a complete listing of
        these patterns, please refer to table <link linkend="patterns">patterns</link> in the Reference chapter.
      </para>
      
      <para>
        It must be noted that in this table, <literal>EXPR</literal> is
        a regular expression. For ranges, the forms
        <literal>&lt;[MAX]</literal>, <literal>&gt;&#62;[MIN]</literal>,
        <literal> [MIN]- </literal> and <literal>-[MAX]</literal> are
        also possible.
      </para>
      
      <sect2>
        <title>Complex Patterns </title>
        
        <para>
          It is possible to combine several sub-patterns to a more complex
          pattern. The most simple possibility is to logically AND several
          patterns by stringing them together:
        </para>
        
        <para>
          
          <screen>
~s 'SPAM' ~U</screen>
          
        </para>
        
        <para>
          The pattern above matches all messages that contain ``SPAM'' in
          the subject and are unread.
        </para>
        
        <para>
          To logical OR patterns, simply use the <literal>&verbar;</literal>
          operator. This one
          especially useful when using local groups:
        </para>
        
        <para>
          
          <screen>
~f ("nion@muttng\.org"|"ak@muttng\.org"|"pdmef@muttng\.org")
(~b mutt-ng|~s Mutt-ng)
!~x '@synflood\.at'</screen>
          
        </para>
        
        <para>
          The first pattern matches all messages that were sent by one of
          the mutt-ng maintainers, while the seconds pattern matches all
          messages that contain ``mutt-ng'' in the message body or ``Mutt-ng''
          in the subject. The third pattern matches all messages that do not
          contain ``@synflood\.at'' in the <literal>References:</literal>
          header, i.e.
          messages that are not an (indirect) reply to one of my messages. A
          pattern can be logicall negated using the <literal>!</literal>
          operator.
        </para>
        
      </sect2>
      
      <sect2>
        <title>Patterns and Dates </title>
        
        <para>
          When using dates in patterns, the dates must be specified in a
          special format, i.e.  <literal>DD/MM/YYYY</literal>. If you don't
          specify
          month or year, they default to the current month or year. When using
          date ranges, and you specify only the minimum or the maximum, the
          specified date will be excluded, e.g. <literal>01/06/2005-</literal>
          matches
          against all messages <emphasis>after</emphasis> Juni 1st, 2005.
        </para>
        
        <para>
          It is also possible to use so-called ``error margins'' when
          specifying date ranges.  You simply specify a date, and then the
          error margin. This margin needs to contain the information whether
          it goes ``forth'' or ``back'' in time, by using <literal>+</literal>
          and <literal>-</literal>.
          Then follows a number and a unit, i.e. <literal>y</literal> for
          years, <literal>m</literal> for
          months, <literal>w</literal> for weeks and <literal>d</literal> for
          days. If you use the special
          <literal>*</literal> sign, it means that the error margin goes to
          both``directions'' in time.
        </para>
        
        <para>
          
          <screen>
~d 01/01/2005+1y
~d 18/10/2004-2w
~d 28/12/2004*1d</screen>
          
        </para>
        
        <para>
          The first pattern matches all dates between January 1st, 2005 and
          January 1st 2006.  The second pattern matches all dates between
          October 18th, 2004 and October 4th 2004 (2 weeks before 18/10/2004),
          while the third pattern matches all dates 1 day around December
          28th, 2004 (i.e. Dec 27th, 28th and 29th).
        </para>
        
        <para>
          Relative dates are also very important, as they make it possible
          to specify date ranges between a fixed number of units and the
          current date. How this works can be seen in the following example:
        </para>
        
        <para>
          
          <screen>
~d &gt;2w # messages older than two weeks
~d &lt;3d # messages newer than 3 days
~d =1m # messages that are exactly one month old</screen>
          
        </para>
        
        <para>
          
        </para>
        
      </sect2>
      
    </sect1>
    
    <sect1>
      <title>Format Strings      </title>
      
      <sect2>
        <title>Introduction        </title>
        
        <para>
          The so called <emphasis>Format Strings</emphasis> offer great
          flexibility when
          configuring mutt-ng. In short, they describe what items to print
          out how in menus and status messages.
        </para>
        
        <para>
          Basically, they work as this: for different menus and bars,
          there's a variable specifying the layout. For every item
          available, there is a so called <emphasis>expando</emphasis>.
        </para>
        
        <para>
          For example, when running mutt-ng on different machines or
          different versions for testing purposes, it may be interesting to
          have the following information always printed on screen when one
          is in the index:
        </para>
        
        <para>
          
          <itemizedlist>
            <listitem>
              
              <para>
                the current hostname
                
              </para>
            </listitem>
            <listitem>
              
              <para>
                the current mutt-ng version number
                
              </para>
            </listitem>
            
          </itemizedlist>
          
        </para>
        
        <para>
          The setting for the status bar of the index is controlled via the
          <link linkend="status-format">status-format</link>
          variable. For the hostname and version string, there's an expando
          for <literal>&dollar;status&lowbar;format</literal>: <literal>
            &percnt;h
          </literal>
          expands to the
          hostname and <literal>&percnt;v</literal> to the version string. When
          just configuring:
        </para>
        
        <para>
          
          <screen>
set status_format = "%v on %h: ..."</screen>
          
        </para>
        
        <para>
          mutt-ng will replace the sequence <literal>&percnt;v</literal> with
          the version string
          and <literal>&percnt;h</literal> with the host's name. When you are,
          for example, running
          mutt-ng version <literal>1.5.9i</literal> on host <literal>mailhost</literal>, you'll see the
          following when you're in the index:
        </para>
        
        <para>
          
          <screen>
Mutt-ng 1.5.9i on mailhost: ...</screen>
          
        </para>
        
        <para>
          In the index, there're more useful information one could want to 
          see:
        </para>
        
        <para>
          
          <itemizedlist>
            <listitem>
              
              <para>
                which mailbox is open
                
              </para>
            </listitem>
            <listitem>
              
              <para>
                how man new, flagged or postponed messages
                
              </para>
            </listitem>
            <listitem>
              
              <para>
                ...
                
              </para>
            </listitem>
            
          </itemizedlist>
          
        </para>
        
        <para>
          To include the mailbox' name is as easy as:
        </para>
        
        <para>
          
          <screen>
set status_format = "%v on %h: %B: ...</screen>
          
        </para>
        
        <para>
          When the currently opened mailbox is <literal>Inbox</literal>, this
          will be expanded
          to:
        </para>
        
        <para>
          
          <screen>
Mutt-ng 1.5.9i on mailhost: Inbox: ...</screen>
          
        </para>
        
        <para>
          For the number of certain types of messages, one more feature of the
          format
          strings is extremely useful. If there aren't messages of a certain
          type, it
          may not be desired to print just that there aren't any but instead
          only
          print something if there are any.
        </para>
        
        <para>
          
        </para>
        
      </sect2>
      
      <sect2>
        <title>Conditional Expansion        </title>
        
        <para>
          To only print the number of messages if there are new messages in
          the current mailbox, further extend
          <literal>&dollar;status&lowbar;format</literal> to:
        </para>
        
        <para>
          
          <screen>
set status_format = "%v on %h: %B %?n?%n new? ...</screen>
          
        </para>
        
        <para>
          This feature is called <emphasis>nonzero-printing</emphasis> and
          works as this:
          some expandos may be optionally printed nonzero, i.e.  a portion
          of the format string is only evaluated if the value of the expando
          is different from zero. The basic syntax is:
        </para>
        
        <para>
          
          <screen>
%?&#60;item&#62;?&#60;string if nonzero&#62;?</screen>
          
        </para>
        
        <para>
          which tells mutt-ng to only look at <literal>&lt;string if
            nonzero&gt;
          </literal>
          if the value of the <literal>&percnt;&lt;item&percnt;gt;</literal>
          expando is different from zero. In our example, we used <literal>n</literal> as
          the expando to check for and <literal>&percnt;n new</literal> as the
          optional nonzero
          string.
        </para>
        
        <para>
          But this is not all: this feature only offers one alternative: 
          ``print something if not zero.'' Mutt-ng does, as you might guess, 
          also provide a logically complete version: ``if zero, print 
          something and else print something else.'' This is achieved by the 
          following syntax for those expandos which may be printed nonzero:
        </para>
        
        <para>
          
          <screen>
%?&#60;item&#62;?&#60;string if nonzero&#62;&#38;&#60;string if zero&#62;?</screen>
          
        </para>
        
        <para>
          Using this we can make mutt-ng to do the following:
        </para>
        
        <para>
          
          <itemizedlist>
            <listitem>
              
              <para>
                make it print ``<emphasis>n</emphasis> new messages'' whereby <emphasis>
                  n
                </emphasis>
                is the
                count but only if there new ones
                
              </para>
            </listitem>
            <listitem>
              
              <para>
                and make it print ``no new messages'' if there aren't any
                
              </para>
            </listitem>
            
          </itemizedlist>
          
        </para>
        
        <para>
          The corresponding configuration is:
        </para>
        
        <para>
          
          <screen>
set status_format = "%v on %h: %B: %?n?%n new messages&amp;no new messages? ...</screen>
          
        </para>
        
        <para>
          This doubles the use of the ``new messages'' string because it'll get
          always printed. Thus, it can be shortened to:
        </para>
        
        <para>
          
          <screen>
set status_format = "%v on %h: %B: %?n?%n&amp;no? new messages ...</screen>
          
        </para>
        
        <para>
          As you might see from this rather simple example, one can create
          very complex but fancy status messages. Please see the reference
          chapter for expandos and those which may be printed nonzero.
        </para>
        
        <para>
          
        </para>
        
      </sect2>
      
      <sect2>
        <title>Modifications and Padding        </title>
        
        <para>
          Besides the information given so far, there're even more features of
          format strings:
        </para>
        
        <para>
          
          <itemizedlist>
            <listitem>
              
              <para>
                When specifying <literal>&percnt;&lowbar;&lt;item&gt;</literal>
                instead of
                just <literal>&percnt;&lt;item&gt;</literal>, mutt-ng will
                convert all
                characters in the expansion of <literal>&lt;item&gt;</literal>
                to
                lowercase.
                
              </para>
            </listitem>
            <listitem>
              
              <para>
                When specifying <literal>&percnt;:&lt;item&gt;</literal>
                instead of just
                <literal>&percnt;&lt;item&gt;</literal>, mutt-ng will convert
                all dots in the
                expansion of <literal>&lt;item&gt;</literal> to underscores
                (<literal>&lowbar;</literal>).
                
              </para>
            </listitem>
            
          </itemizedlist>
          
        </para>
        
        <para>
          Also, there's a feature called <emphasis>Padding</emphasis> supplied
          by the
          following two expandos: <literal>&percnt;&verbar;X</literal> and <literal>
            &percnt;&gt;X
          </literal>
          .
        </para>
        
        <para>
          <variablelist>
            
            <varlistentry>
              <term>
                <literal>&percnt;&verbar;X</literal>
              </term>
              <listitem>
                <para>
                  When this occurs, mutt-ng will fill the
                  rest of the line with the character <literal>X</literal>. In
                  our example,
                  filling the rest of the line with dashes is done by setting:
                </para>
                
                <para>
                  
                  <screen>
set status_format = "%v on %h: %B: %?n?%n&amp;no? new messages %|-"</screen>
                  
                </para>
              </listitem>
            </varlistentry>
            <varlistentry>
              <term>
                <literal>&percnt;&gt;X</literal>
              </term>
              <listitem>
                <para>
                  Since the previous expando stops at
                  the end of line, there must be a way to fill the gap between
                  two items via the <literal>&percnt;&gt;X</literal> expando:
                  it puts as many
                  characters <literal>X</literal> in between two items so that
                  the rest of
                  the line will be right-justified. For example, to not put the
                  version string and hostname of our example on the left but on
                  the right and fill the gap with spaces, one might use (note
                  the space after <literal>&percnt;&gt;</literal>):
                </para>
                
                <para>
                  
                  <screen>
set status_format = "%B: %?n?%n&amp;no? new messages %&#62; (%v on %h)"</screen>
                  
                </para>
              </listitem>
            </varlistentry>
          </variablelist>
        </para>
        
        <para>
          
        </para>
        
        <para>
          
        </para>
        
      </sect2>
      
    </sect1>
    
    <sect1>
      <title>Using Tags  </title>
      
      <para>
        Sometimes it is desirable to perform an operation on a group of
        messages all at once rather than one at a time.  An example might be
        to save messages to a mailing list to a separate folder, or to
        delete all messages with a given subject.  To tag all messages
        matching a pattern, use the tag-pattern function, which is bound to
        ``shift-T'' by default.  Or you can select individual messages by
        hand using the ``tag-message'' function, which is bound to ``t'' by
        default.  See <link linkend="patterns">patterns</link> for Mutt-ng's
        pattern
        matching syntax.
      </para>
      
      <para>
        Once you have tagged the desired messages, you can use the
        ``tag-prefix'' operator, which is the ``;'' (semicolon) key by default.
        When the ``tag-prefix'' operator is used, the <emphasis role="bold">
          next
        </emphasis>
        operation will
        be applied to all tagged messages if that operation can be used in that
        manner.  If the <link linkend="auto-tag">auto-tag</link>
        variable is set, the next operation applies to the tagged messages
        automatically, without requiring the ``tag-prefix''.
      </para>
      
      <para>
        In <link linkend="macro">macro</link> or <link linkend="push">push</link> commands,
        you can use the ``tag-prefix-cond'' operator.  If there are no tagged
        messages, mutt will "eat" the rest of the macro to abort it's
        execution.Mutt-ng will stop "eating" the macro when it encounters the
        ``end-cond''
        operator;  after this operator the rest of the macro will be executed
        asnormal.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="hooks">
      <title>Using Hooks  </title>
      
      <para>
        A <emphasis>hook</emphasis> is a concept borrowed from the EMACS editor
        which allows you to
        execute arbitrary commands before performing some operation.  For
        example,
        you may wish to tailor your configuration based upon which mailbox you
        are
        reading, or to whom you are sending mail.  In the Mutt-ng world, a <emphasis>
          hook
        </emphasis>
        consists of a <link linkend="regexp">regexp</link> or
        <link linkend="patterns">patterns</link> along with a
        configuration option/command.  See
        
        <itemizedlist>
          <listitem>
            
            <para>
              <link linkend="folder-hook">folder-hook</link>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <link linkend="send-hook">send-hook</link>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <link linkend="message-hook">message-hook</link>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <link linkend="save-hook">save-hook</link>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <link linkend="mbox-hook">mbox-hook</link>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <link linkend="fcc-hook">fcc-hook</link>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <link linkend="fcc-save-hook">fcc-save-hook</link>
            </para>
          </listitem>
          
        </itemizedlist>
        
        for specific details on each type of <emphasis>hook</emphasis>
        available.
      </para>
      
      <para>
        <emphasis role="bold">Note:</emphasis> if a hook changes configuration
        settings, these changes remain
        effective until the end of the current mutt session. As this is
        generally
        not desired, a default hook needs to be added before all other hooks to
        restore configuration defaults. Here is an example with send-hook and
        the
        my&lowbar;hdr directive:
      </para>
      
      <para>
        
        <screen>
send-hook . 'unmy_hdr From:'
send-hook ~C'^b@b\.b$' my_hdr from: c@c.c</screen>
        
      </para>
      
      <sect2 id="pattern-hook">
        <title>Message Matching in Hooks</title>
        
        <para>
          Hooks that act upon messages (<literal>send-hook, save-hook,
            fcc-hook,message-hook
          </literal>
          )are evaluated in a slightly different manner.  For the other
          types of hooks, a <link linkend="regexp">regexp</link> is
          sufficient.  But in dealing with messages a finer grain of control is
          needed for matching since for different purposes you want to match
          different criteria.
        </para>
        
        <para>
          Mutt-ng allows the use of the <link linkend="patterns">patterns</link>
          language for matching messages in hook commands.  This works in
          exactly the same way as it would when <emphasis>limiting</emphasis>
          or<emphasis>searching</emphasis> the mailbox, except that you are
          restricted to those
          operators which match information mutt extracts from the header of
          the message (i.e.  from, to, cc, date, subject, etc.).
        </para>
        
        <para>
          For example, if you wanted to set your return address based upon
          sending
          mail to a specific address, you could do something like:
          
          <screen>
send-hook '~t ^me@cs\.hmc\.edu$' 'my_hdr From: Mutt-ng User &#60;user@host&#62;'</screen>
          
          which would execute the given command when sending mail to
          <emphasis>me@cs.hmc.edu</emphasis>.
        </para>
        
        <para>
          However, it is not required that you write the pattern to match using
          the
          full searching language.  You can still specify a simple <emphasis>
            regular
            expression
          </emphasis>
          like the other hooks, in which case Mutt-ng will translate your
          pattern into the full language, using the translation specified by
          the 
          <link linkend="default-hook">default-hook</link> variable.  The
          pattern is translated at the time the hook is declared, so the value
          of 
          <link linkend="default-hook">default-hook</link> that is in effect
          at that time will be used.
        </para>
        
        <para>
          
        </para>
        
      </sect2>
      
    </sect1>
    
    <sect1 id="sidebar">
      <title>Using the sidebar  </title>
      
      <para>
        The sidebar, a feature specific to Mutt-ng, allows you to use a mailbox
        listing 
        which looks very similar to the ones you probably know from GUI mail
        clients.
        The sidebar lists all specified mailboxes, shows the number in each
        and highlights the ones with new email
        Use the following configuration commands:
        
        <screen>
set sidebar_visible="yes"
set sidebar_width=25</screen>
        
      </para>
      
      <para>
        If you want to specify the mailboxes you can do so with:
        
        <screen>
set mbox='=INBOX'
mailboxes INBOX \
MBOX1 \
MBOX2 \
...</screen>
        
      </para>
      
      <para>
        You can also specify the colors for mailboxes with new mails by using:
        
        <screen>
color sidebar_new red black
color sidebar white black</screen>
        
      </para>
      
      <para>
        The available functions are:

        <table>
          <title>Default Sidebar Function Bindings</title>
          <tgroup cols="3" align="left" colsep="1" rowsep="1">
          <thead>
            <row>
              <entry>Key</entry>
              <entry>Function</entry>
              <entry>Description</entry>
            </row>
          </thead>
          <tbody>
            <row><entry><code>none</code></entry><entry><code>sidebar-scroll-up    </code></entry><entry>Scrolls the mailbox list up 1 page</entry></row>
            <row><entry><code>none</code></entry><entry><code>sidebar-scroll-down </code></entry><entry>Scrolls the mailbox list down 1 page</entry></row>
            <row><entry><code>none</code></entry><entry><code>sidebar-next       </code></entry><entry>Highlights the next mailbox</entry></row>
            <row><entry><code>none</code></entry><entry><code>sidebar-next-new  </code></entry><entry>Highlights the next mailbox with new mail</entry></row>
            <row><entry><code>none</code></entry><entry><code>sidebar-previous  </code></entry><entry>Highlights the previous mailbox</entry></row>
            <row><entry><code>none</code></entry><entry><code>sidebar-open      </code></entry><entry>Opens the currently highlighted mailbox</entry></row>
          </tbody>
        </tgroup>
      </table>

      </para>
      
      <para>
        Reasonable key bindings look e.g. like this:
        
        <screen>
bind index \Cp sidebar-prev
bind index \Cn sidebar-next
bind index \Cb sidebar-open
bind pager \Cp sidebar-prev
bind pager \Cn sidebar-next
bind pager \Cb sidebar-open

macro index B ':toggle sidebar_visible^M'
macro pager B ':toggle sidebar_visible^M'</screen>
        
      </para>
      
      <para>
        You can then go up and down by pressing Ctrl-P and Ctrl-N, and 
        switch on and off the sidebar simply by pressing 'B'.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="query">
      <title>External Address Queries  </title>
      
      <para>
        Mutt-ng supports connecting to external directory databases such as
        LDAP,
        ph/qi, bbdb, or NIS through a wrapper script which connects to mutt
        using a simple interface.  Using the <link linkend="query-command">
          query-command
        </link>
        variable, you specify the wrapper
        command to use.  For example:
      </para>
      
      <para>
        
        <screen>
set query_command = "mutt_ldap_query.pl '%s'"</screen>
        
      </para>
      
      <para>
        The wrapper script should accept the query on the command-line.  It
        should return a one line message, then each matching response on a
        single line, each line containing a tab separated address then name
        thensome other optional information.  On error, or if there are no
        matching
        addresses, return a non-zero exit code and a one line error message.
      </para>
      
      <para>
        An example multiple response output:
        
        <screen>
Searching database ... 20 entries ... 3 matching:
me@cs.hmc.edu           Michael Elkins  mutt dude
blong@fiction.net       Brandon Long    mutt and more
roessler@guug.de        Thomas Roessler mutt pgp</screen>
        
      </para>
      
      <para>
        There are two mechanisms for accessing the query function of mutt.  One
        is to do a query from the index menu using the query function (default:
        Q).
        This will prompt for a query, then bring up the query menu which will
        list the matching responses.  From the query menu, you can select
        addresses to create aliases, or to mail.  You can tag multiple
        addressesto mail, start a new query, or have a new query appended to
        the current
        responses.
      </para>
      
      <para>
        The other mechanism for accessing the query function is for address
        completion, similar to the alias completion.  In any prompt for address
        entry, you can use the complete-query function (default: &circ;T) to
        run a
        query based on the current address you have typed.  Like aliases, mutt
        will look for what you have typed back to the last space or comma.  If
        there is a single response for that query, mutt will expand the address
        in place.  If there are multiple responses, mutt will activate the
        querymenu.  At the query menu, you can select one or more addresses to
        be
        added to the prompt.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1>
      <title>Mailbox Formats  </title>
      
      <para>
        Mutt-ng supports reading and writing of four different mailbox formats:
        mbox, MMDF, MH and Maildir.  The mailbox type is autodetected, so there
        is no need to use a flag for different mailbox types.  When creating
        newmailboxes, Mutt-ng uses the default specified with the <link linkend="mbox-type">
          mbox-type
        </link>
        variable.
      </para>
      
      <para>
        <emphasis role="bold">mbox</emphasis>.  This is the most widely used
        mailbox format for UNIX.  All
        messages are stored in a single file.  Each message has a line of the
        form:
      </para>
      
      <para>
        
        <screen>
From me@cs.hmc.edu Fri, 11 Apr 1997 11:44:56 PST</screen>
        
      </para>
      
      <para>
        to denote the start of a new message (this is often referred to as the
        ``From&lowbar;'' line).
      </para>
      
      <para>
        <emphasis role="bold">MMDF</emphasis>.  This is a variant of the <emphasis>
          mbox
        </emphasis>
        format.  Each message is
        surrounded by lines containing ``&circ;A&circ;A&circ;A&circ;A'' (four
        control-A's).
      </para>
      
      <para>
        <emphasis role="bold">MH</emphasis>. A radical departure from <emphasis>
          mbox
        </emphasis>
        and <emphasis>MMDF</emphasis>, a mailbox
        consists of a directory and each message is stored in a separate file.
        The filename indicates the message number (however, this is may not
        correspond to the message number Mutt-ng displays). Deleted messages
        arerenamed with a comma (,) prepended to the filename. <emphasis role="bold">
          Note:
        </emphasis>
        Mutt
        detects this type of mailbox by looking for either <literal>
          .mh&lowbar;sequences
        </literal>
        or <literal>.xmhcache</literal> (needed to distinguish normal
        directories from MH
        mailboxes).
      </para>
      
      <para>
        <emphasis role="bold">Maildir</emphasis>.  The newest of the mailbox
        formats, used by the Qmail MTA (a
        replacement for sendmail).  Similar to <emphasis>MH</emphasis>, except
        that it adds three
        subdirectories of the mailbox: <emphasis>tmp</emphasis>, <emphasis>new</emphasis> and <emphasis>
          cur
        </emphasis>
        .Filenames
        for the messages are chosen in such a way they are unique, even when
        twoprograms are writing the mailbox over NFS, which means that no file
        locking
        is needed.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="shortcuts">
      <title>Mailbox Shortcuts  </title>
      
      <para>
        There are a number of built in shortcuts which refer to specific
        mailboxes.
        These shortcuts can be used anywhere you are prompted for a file or
        mailbox
        path.
      </para>
      
      <para>
        
        <itemizedlist>
          <listitem>
            
            <para>
              ! -- refers to your <link linkend="spoolfile">spoolfile</link>
              (incoming) mailbox
            </para>
          </listitem>
          <listitem>
            
            <para>
              &gt; -- refers to your <link linkend="mbox">mbox</link> file
            </para>
          </listitem>
          <listitem>
            
            <para>
              &lt; -- refers to your <link linkend="record">record</link> file
            </para>
          </listitem>
          <listitem>
            
            <para>
              &circ; -- refers to the current mailbox
            </para>
          </listitem>
          <listitem>
            
            <para>
              - or !! -- refers to the file you've last visited
            </para>
          </listitem>
          <listitem>
            
            <para>
              &tilde; -- refers to your home directory
            </para>
          </listitem>
          <listitem>
            
            <para>
              = or + -- refers to your <link linkend="folder">folder</link>
              directory
            </para>
          </listitem>
          <listitem>
            
            <para>
              @<emphasis>alias</emphasis> -- refers to the <link linkend="save-hook">
                save-hook
              </link>
              as determined by the address of the alias
            </para>
          </listitem>
          
        </itemizedlist>
        
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="using-lists">
      <title>Handling Mailing Lists  </title>
      
      <para>
        Mutt-ng has a few configuration options that make dealing with large
        amounts of mail easier.  The first thing you must do is to let Mutt
        know what addresses you consider to be mailing lists (technically
        this does not have to be a mailing list, but that is what it is most
        often used for), and what lists you are subscribed to.  This is
        accomplished through the use of the <link linkend="lists">lists</link>
        commands in your muttrc.
      </para>
      
      <para>
        Now that Mutt-ng knows what your mailing lists are, it can do several
        things, the first of which is the ability to show the name of a list
        through which you received a message (i.e., of a subscribed list) in
        the <emphasis>index</emphasis> menu display.  This is useful to
        distinguish between
        personal and list mail in the same mailbox.  In the <link linkend="index-format">
          index-format
        </link>
        variable, the escape ``&percnt;L''
        will return the string ``To &lt;list&gt;'' when ``list'' appears in the
        ``To'' field, and ``Cc &lt;list&gt;'' when it appears in the ``Cc''
        field (otherwise it returns the name of the author).
      </para>
      
      <para>
        Often times the ``To'' and ``Cc'' fields in mailing list messages
        tend to get quite large. Most people do not bother to remove the
        author of the message they are reply to from the list, resulting in
        two or more copies being sent to that person.  The ``list-reply''
        function, which by default is bound to ``L'' in the <emphasis>index</emphasis> menu
        and <emphasis>pager</emphasis>, helps reduce the clutter by only
        replying to the
        known mailing list addresses instead of all recipients (except as
        specified by <literal>Mail-Followup-To</literal>, see below).
      </para>
      
      <para>
        Mutt-ng also supports the <literal>Mail-Followup-To</literal> header. 
        When you send
        a message to a list of recipients which includes one or several
        subscribed mailing lists, and if the <link linkend="followup-to">
          followup-to
        </link>
        option is set, mutt will generate
        a Mail-Followup-To header which contains all the recipients to whom
        you send this message, but not your address. This indicates that
        group-replies or list-replies (also known as ``followups'') to this
        message should only be sent to the original recipients of the
        message, and not separately to you - you'll receive your copy through
        one of the mailing lists you are subscribed to.
      </para>
      
      <para>
        Conversely, when group-replying or list-replying to a message which
        has a <literal>Mail-Followup-To</literal> header, mutt will respect
        this header if
        the <link linkend="honor-followup-to">honor-followup-to</link>
        configuration
        variable is set.  Using list-reply will in this case also make sure
        that the reply goes to the mailing list, even if it's not specified
        in the list of recipients in the <literal>Mail-Followup-To</literal>.
      </para>
      
      <para>
        Note that, when header editing is enabled, you can create a
        <literal>Mail-Followup-To</literal> header manually.  Mutt-ng will only
        auto-generate
        this header if it doesn't exist when you send the message.
      </para>
      
      <para>
        The other method some mailing list admins use is to generate a
        ``Reply-To'' field which points back to the mailing list address rather
        than the author of the message.  This can create problems when trying
        to reply directly to the author in private, since most mail clients
        will automatically reply to the address given in the ``Reply-To''
        field.  Mutt-ng uses the <link linkend="reply-to">reply-to</link>
        variable to help decide which address to use.  If set to <emphasis>
          ask-yes
        </emphasis>
        or
        <emphasis>ask-no</emphasis>, you will be
        prompted as to whether or not you would like to use the address given
        inthe ``Reply-To'' field, or reply directly to the address given in the
        ``From'' field.  When set to <emphasis>yes</emphasis>, the ``Reply-To''
        field will be used when
        present.
      </para>
      
      <para>
        The ``X-Label:'' header field can be used to further identify mailing
        lists or list subject matter (or just to annotate messages
        individually).  The <link linkend="index-format">index-format</link>
        variable's ``&percnt;y'' and
        ``&percnt;Y'' escapes can be used to expand ``X-Label:'' fields in the
        index, and Mutt-ng's pattern-matcher can match regular expressions to
        ``X-Label:'' fields with the ``&tilde;y'' selector.  ``X-Label:'' is
        not a
        standard message header field, but it can easily be inserted by
        procmailand other mail filtering agents.
      </para>
      
      <para>
        Lastly, Mutt-ng has the ability to <link linkend="sort">sort</link> the
        mailbox into
        <link linkend="threads">threads</link>.  A thread is a group of
        messages which all relate to the same
        subject.  This is usually organized into a tree-like structure where a
        message and all of its replies are represented graphically.  If you've
        ever
        used a threaded news client, this is the same concept.  It makes
        dealingwith large volume mailing lists easier because you can easily
        delete
        uninteresting threads and quickly find topics of value.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1>
      <title>Editing threads  </title>
      
      <para>
        Mutt-ng has the ability to dynamically restructure threads that are
        broken
        either by misconfigured software or bad behavior from some
        correspondents. This allows to clean your mailboxes formats) from these
        annoyances which make it hard to follow a discussion.
      </para>
      
      <sect2>
        <title>Linking threads</title>
        
        <para>
          Some mailers tend to "forget" to correctly set the "In-Reply-To:" and
          "References:" headers when replying to a message. This results in
          broken
          discussions because Mutt-ng has not enough information to guess the
          correct
          threading.
          You can fix this by tagging the reply, then moving to the parent
          message
          and using the ``link-threads'' function (bound to &#38; by default).
          The
          reply will then be connected to this "parent" message.
        </para>
        
        <para>
          You can also connect multiple children at once, tagging them and
          using the
          tag-prefix command (';') or the auto&lowbar;tag option.
        </para>
        
      </sect2>
      
      <sect2>
        <title>Breaking threads</title>
        
        <para>
          On mailing lists, some people are in the bad habit of starting a new
          discussion by hitting "reply" to any message from the list and
          changing
          the subject to a totally unrelated one.
          You can fix such threads by using the ``break-thread'' function
          (boundby default to &num;), which will turn the subthread starting
          from the
          current message into a whole different thread.
        </para>
        
        <para>
          
        </para>
        
      </sect2>
      
    </sect1>
    
    <sect1 id="dsn">
      <title>Delivery Status Notification (DSN) Support  </title>
      
      <para>
        RFC1894 defines a set of MIME content types for relaying information
        about the status of electronic mail messages.  These can be thought of
        as
        ``return receipts.''
      </para>
      
      <para>
        Users can make use of it in one of the following two ways:
      </para>
      
      <para>
        
        <itemizedlist>
          <listitem>
            
            <para>
              Berkeley sendmail 8.8.x currently has some command line options
              in which the mail client can make requests as to what type of
              status
              messages should be returned.
            </para>
          </listitem>
          <listitem>
            
            <para>
              The SMTP support via libESMTP supports it, too.
            </para>
          </listitem>
          
        </itemizedlist>
        
      </para>
      
      <para>
        To support this, there are two variables:
      </para>
      
      <para>
        
        <itemizedlist>
          <listitem>
            
            <para>
              <link linkend="dsn-notify">dsn-notify</link> is used
              to request receipts for different results (such as failed
              message,message delivered, etc.).
              
            </para>
          </listitem>
          <listitem>
            
            <para>
              <link linkend="dsn-return">dsn-return</link> requests
              how much of your message should be returned with the receipt
              (headers or full message).
              
            </para>
          </listitem>
          
        </itemizedlist>
        
      </para>
      
      <para>
        Please see the reference chapter for possible values.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1>
      <title>POP3 Support (OPTIONAL)  </title>
      
      <para>
        If Mutt-ng was compiled with POP3 support (by running the <emphasis>
          configure
        </emphasis>
        script with the <emphasis>--enable-pop</emphasis> flag), it has the
        ability to work
        with mailboxes located on a remote POP3 server and fetch mail for local
        browsing.
      </para>
      
      <para>
        You can access the remote POP3 mailbox by selecting the folder
        <literal>pop://popserver/</literal>.
      </para>
      
      <para>
        You can select an alternative port by specifying it with the server,
        i.e.:
        <literal>pop://popserver:port/</literal>.
      </para>
      
      <para>
        You can also specify different username for each folder, i.e.:
        <literal>pop://username@popserver[:port]/</literal>.
      </para>
      
      <para>
        Polling for new mail is more expensive over POP3 than locally. For this
        reason the frequency at which Mutt-ng will check for mail remotely can
        be
        controlled by the
        <link linkend="pop-mail-check">pop-mail-check</link>
        variable, which defaults to every 60 seconds.
      </para>
      
      <para>
        If Mutt-ng was compiled with SSL support (by running the <emphasis>
          configure
        </emphasis>
        script with the <emphasis>--with-ssl</emphasis> flag), connections to
        POP3 servers
        can be encrypted. This naturally requires that the server supports
        SSL encrypted connections. To access a folder with POP3/SSL, you should
        use pops: prefix, ie:
        <literal>pops://[username@]popserver[:port]/</literal>.
      </para>
      
      <para>
        Another way to access your POP3 mail is the <emphasis>fetch-mail</emphasis> function
        (default: G).  It allows to connect to <link linkend="pop-host">
          pop-host
        </link>
        ,fetch all your new mail and place it in the
        local <link linkend="spoolfile">spoolfile</link>.  After this
        point, Mutt-ng runs exactly as if the mail had always been local.
      </para>
      
      <para>
        <emphasis role="bold">Note:</emphasis> If you only need to fetch all
        messages to local mailbox
        you should consider using a specialized program, such as
        <ulink
          URL="http://www.ccil.org/~esr/fetchmail">fetchmail</ulink>
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1>
      <title>IMAP Support (OPTIONAL)  </title>
      
      <para>
        If Mutt-ng was compiled with IMAP support (by running the <emphasis>
          configure
        </emphasis>
        script with the <emphasis>--enable-imap</emphasis> flag), it has the
        ability to work
        with folders located on a remote IMAP server.
      </para>
      
      <para>
        You can access the remote inbox by selecting the folder
        <literal>imap://imapserver/INBOX</literal>, where <literal>imapserver</literal> is the name of the
        IMAP server and <literal>INBOX</literal> is the special name for your
        spool mailbox on
        the IMAP server. If you want to access another mail folder at the IMAP
        server, you should use <literal>imap://imapserver/path/to/folder</literal> where
        <literal>path/to/folder</literal> is the path of the folder you want to
        access.
      </para>
      
      <para>
        You can select an alternative port by specifying it with the server,
        i.e.:
        <literal>imap://imapserver:port/INBOX</literal>.
      </para>
      
      <para>
        You can also specify different username for each folder, i.e.:
        <literal>imap://username@imapserver[:port]/INBOX</literal>.
      </para>
      
      <para>
        If Mutt-ng was compiled with SSL support (by running the <emphasis>
          configure
        </emphasis>
        script with the <emphasis>--with-ssl</emphasis> flag), connections to
        IMAP servers
        can be encrypted. This naturally requires that the server supports
        SSL encrypted connections. To access a folder with IMAP/SSL, you should
        use <literal>imaps://[username@]imapserver[:port]/path/to/folder</literal> as your 
        folder path.
      </para>
      
      <para>
        Pine-compatible notation is also supported, i.e.
        <literal>&lcub;[username@]imapserver[:port][/ssl]&rcub;path/to/folder</literal>
      </para>
      
      <para>
        Note that not all servers use / as the hierarchy separator.  Mutt-ng
        should
        correctly notice which separator is being used by the server and
        convertpaths accordingly.
      </para>
      
      <para>
        When browsing folders on an IMAP server, you can toggle whether to look
        at only the folders you are subscribed to, or all folders with the
        <emphasis>toggle-subscribed</emphasis> command.  See also the 
        <link linkend="imap-list-subscribed">imap-list-subscribed</link>
        variable.
      </para>
      
      <para>
        Polling for new mail on an IMAP server can cause noticeable delays. So,
        you'll
        want to carefully tune the
        <link linkend="imap-mail-check">imap-mail-check</link>
        and
        <link linkend="timeout">timeout</link>
        variables.
      </para>
      
      <para>
        Note that if you are using mbox as the mail store on UW servers prior
        tov12.250, the server has been reported to disconnect a client if
        another client
        selects the same folder.
      </para>
      
      <sect2>
        <title>The Folder Browser</title>
        
        <para>
          As of version 1.2, mutt supports browsing mailboxes on an IMAP
          server. This is mostly the same as the local file browser, with the
          following differences:
          
          <itemizedlist>
            <listitem>
              
              <para>
                Instead of file permissions, mutt displays the string "IMAP",
                possibly followed by the symbol "+", indicating
                that the entry contains both messages and subfolders. On
                Cyrus-like servers folders will often contain both messages and
                subfolders. 
              </para>
            </listitem>
            <listitem>
              
              <para>
                For the case where an entry can contain both messages and
                subfolders, the selection key (bound to <literal>enter</literal> by default)
                will choose to descend into the subfolder view. If you wish to
                view
                the messages in that folder, you must use <literal>view-file</literal> instead
                (bound to <literal>space</literal> by default).
              </para>
            </listitem>
            <listitem>
              
              <para>
                You can create, delete and rename mailboxes with the
                <literal>create-mailbox</literal>, <literal>delete-mailbox</literal>, and
                <literal>rename-mailbox</literal> commands (default bindings: <literal>
                  C
                </literal>
                ,
                <literal>d</literal> and <literal>r</literal>, respectively).
                You may also
                <literal>subscribe</literal> and <literal>unsubscribe</literal>
                to mailboxes (normally
                these are bound to <literal>s</literal> and <literal>u</literal>, respectively).
              </para>
            </listitem>
            
          </itemizedlist>
          
        </para>
        
      </sect2>
      
      <sect2>
        <title>Authentication</title>
        
        <para>
          Mutt-ng supports four authentication methods with IMAP servers: SASL,
          GSSAPI, CRAM-MD5, and LOGIN (there is a patch by Grant Edwards to add
          NTLM authentication for you poor exchange users out there, but it has
          yet to be integrated into the main tree). There is also support for
          the pseudo-protocol ANONYMOUS, which allows you to log in to a public
          IMAP server without having an account. To use ANONYMOUS, simply make
          your username blank or "anonymous".
        </para>
        
        <para>
          SASL is a special super-authenticator, which selects among several
          protocols
          (including GSSAPI, CRAM-MD5, ANONYMOUS, and DIGEST-MD5) the most
          secure
          method available on your host and the server. Using some of these
          methods
          (including DIGEST-MD5 and possibly GSSAPI), your entire session will
          be
          encrypted and invisible to those teeming network snoops. It is the
          best
          option if you have it. To use it, you must have the Cyrus SASL
          libraryinstalled on your system and compile mutt with the <emphasis>
            --with-sasl
          </emphasis>
          flag.
        </para>
        
        <para>
          Mutt-ng will try whichever methods are compiled in and available on
          the server,
          in the following order: SASL, ANONYMOUS, GSSAPI, CRAM-MD5, LOGIN.
        </para>
        
        <para>
          There are a few variables which control authentication: 
          
          <itemizedlist>
            <listitem>
              
              <para>
                <link linkend="imap-user">imap-user</link> - controls
                the username under which you request authentication on the IMAP
                server,
                for all authenticators. This is overridden by an explicit
                username in
                the mailbox path (i.e. by using a mailbox name of the form
                <literal>&lcub;user@host&rcub;</literal>).
              </para>
            </listitem>
            <listitem>
              
              <para>
                <link linkend="imap-pass">imap-pass</link> - a
                password which you may preset, used by all authentication
                methods where
                a password is needed.
              </para>
            </listitem>
            <listitem>
              
              <para>
                <link linkend="imap-authenticators">imap-authenticators</link>
                - a colon-delimited list of IMAP
                authentication methods to try, in the order you wish to try
                them. If
                specified, this overrides mutt's default (attempt everything,
                in the order
                listed above).
              </para>
            </listitem>
            
          </itemizedlist>
          
        </para>
        
        <para>
          
        </para>
        
      </sect2>
      
    </sect1>
    
    <sect1 id="reading-news">
      <title>NNTP Support (OPTIONAL)  </title>
      
      <para>
        If compiled with ``--enable-nntp'' option, Mutt-ng can read news from
        a newsserver via NNTP.  You can open a newsgroup with the
        ``change-newsgroup'' function from the index/pager which is by default
        bound to <literal>i</literal>.
      </para>
      
      <para>
        The Default newsserver can be obtained from the
        <literal>&dollar;NNTPSERVER</literal> environment variable. Like other
        news readers,
        info about subscribed newsgroups is saved in a file as specified by the
        <link linkend="nntp-newsrc">nntp-newsrc</link> variable.
        Article headers are cached and can be loaded from a file when a
        newsgroup is entered instead loading from newsserver; currently, this
        caching mechanism still is different from the header caching for
        maildir/IMAP.
      </para>
      
      <sect2>
        <title>Again: Scoring    </title>
        
        <para>
          Especially for Usenet, people often ask for advanced filtering
          and scoring functionality. Of course, mutt-ng has scoring and
          allows a killfile, too. How to use a killfile has been discussed
          in <link linkend="score-command">score-command</link>.
        </para>
        
        <para>
          What has not been discusses in detail is mutt-ng's built-in
          realname filter. For may newsreaders including those for
          ``advanced users'' like <emphasis>slrn</emphasis> or <emphasis>tin</emphasis>, there are frequent
          request for such functionality. The solutions offered often are
          complicated regular expressions.
        </para>
        
        <para>
          In mutt-ng this is as easy as
        </para>
        
        <para>
          
          <screen>
score ~* =42</screen>
          
        </para>
        
        <para>
          This tells mutt-ng to apply a score of 42 to all messages whose
          sender specified a valid realname and a valid email address. Using
        </para>
        
        <para>
          
          <screen>
score !~* =42</screen>
          
        </para>
        
        <para>
          on the contrary applies a score of 42 to all messages <emphasis>not</emphasis>
          matching those criteria which are very strict:
        </para>
        
        <para>
          
          <itemizedlist>
            <listitem>
              
              <para>
                Email addresses must be valid according to RFC 2822, see
                <ulink
                  URL="ftp://ftp.rfc-editor.org/in-notes/rfc2822.txt">&#60;ftp://ftp.rfc-editor.org/in-notes/rfc2822.txt&#62;
                </ulink>
              </para>
            </listitem>
            <listitem>
              
              <para>
                the name must consist of at least 2 fields whereby a field
                must not end in a dot. This means that ``Joe User'' and ``Joe
                A.User'' are valid while ``J. User'' and ``J. A. User'' aren't.
                
              </para>
            </listitem>
            <listitem>
              
              <para>
                it's assumed that users are interested in reading their
                own mail and mail from people who they have defined an alias
                forso that those 2 groups of messages are excluded from the
                strict
                rules.
                
              </para>
            </listitem>
            
          </itemizedlist>
          
        </para>
        
        <para>
          
        </para>
        
        <para>
          
        </para>
        
      </sect2>
      
    </sect1>
    
    <sect1>
      <title>SMTP Support (OPTIONAL)  </title>
      
      <para>
        Mutt-ng can be built using a library called ``libESMTP'' which
        provides SMTP functionality. When <literal>configure</literal> was
        called with
        <literal>--with-libesmtp</literal> or the output <literal>muttng -v</literal> contains
        <literal>+USE&lowbar;LIBESMTP</literal>, this will be or is the case
        already. The SMTP
        support includes support for Delivery Status Notification (see <link linkend="dsn">
          dsn
        </link>
        section) as well as
        handling the <literal>8BITMIME</literal> flag controlled via <link linkend="use-8bitmime">
          use-8bitmime
        </link>
        .
      </para>
      
      <para>
        To enable sending mail directly via SMTP without an MTA such as
        Postfix or SSMTP and the like, simply set the <link linkend="smtp-host">
          smtp-host
        </link>
        variable pointing to your SMTP server.
      </para>
      
      <para>
        Authentication mechanisms are available via the <link linkend="smtp-user">
          smtp-user
        </link>
        and <link linkend="smtp-pass">smtp-pass</link> variables.
      </para>
      
      <para>
        Transport Encryption via the StartTLS command is also available. For
        this to work, first of all Mutt-ng must be built with SSL or GNUTLS.
        Secondly, the <link linkend="smtp-use-tls">smtp-use-tls</link> variable
        must be either set
        to ``enabled'' or ``required.'' In both cases, StartTLS will be used if
        the server supports it: for the second case, the connection will fail
        ifit doesn't while switching back to unencrypted communication for the
        first one.
      </para>
      
      <para>
        Some mail providers require user's to set a particular envelope
        sender, i.e. they allow for only one value which may not be what the
        user wants to send as the <literal>From:</literal> header. In this
        case, the variable
        <link linkend="smtp-envelope">smtp-envelope</link> may be used
        to set the envelope different from the <literal>From:</literal> header.
      </para>
      
    </sect1>
    
    <sect1 id="account-hook">
      <title>Managing multiple IMAP/POP/NNTP accounts (OPTIONAL)  </title>
      
      <para>
        If you happen to have accounts on multiple IMAP and/or POP servers,
        you may find managing all the authentication settings inconvenient and
        error-prone.  The account-hook command may help. This hook works like
        folder-hook but is invoked whenever you access a remote mailbox
        (including inside the folder browser), not just when you open the
        mailbox.
      </para>
      
      <para>
        Some examples:
      </para>
      
      <para>
        
        <screen>
account-hook . 'unset imap_user; unset imap_pass; unset tunnel'
account-hook imap://host1/ 'set imap_user=me1 imap_pass=foo'
account-hook imap://host2/ 'set tunnel="ssh host2 /usr/libexec/imapd"'</screen>
        
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="urlview">
      <title>Start a WWW Browser on URLs (EXTERNAL)  </title>
      
      <para>
        If a message contains URLs (<emphasis>unified resource locator</emphasis> = address in the
        WWW space like <emphasis>http://www.mutt.org/</emphasis>), it is
        efficient to get
        a menu with all the URLs and start a WWW browser on one of them.  This
        functionality is provided by the external urlview program which can be
        retrieved at <ulink URL="ftp://ftp.mutt.org/mutt/contrib/">ftp://ftp.mutt.org/mutt/contrib/</ulink>
>
        and the configuration commands:
        
        <screen>
macro index \cb |urlview\n
macro pager \cb |urlview\n</screen>
        
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1>
      <title>Compressed folders Support (OPTIONAL)  </title>
      
      <para>
        If Mutt-ng was compiled with compressed folders support (by running the
        <emphasis>configure</emphasis> script with the <emphasis>
          --enable-compressed
        </emphasis>
        flag), Mutt
        can open folders stored in an arbitrary format, provided that the user
        has a script to convert from/to this format to one of the accepted.
      </para>
      
      <para>
        The most common use is to open compressed archived folders e.g. with
        gzip.
      </para>
      
      <para>
        In addition, the user can provide a script that gets a folder in an
        accepted format and appends its context to the folder in the
        user-defined format, which may be faster than converting the entire
        folder to the accepted format, appending to it and converting back to
        the user-defined format.
      </para>
      
      <para>
        There are three hooks defined (<link linkend="open-hook">open-hook</link>,
        <link linkend="close-hook">close-hook</link> and <link linkend="append-hook">
          append-hook
        </link>
        )which define commands to uncompress and compress
        a folder and to append messages to an existing compressed folder 
        respectively.
      </para>
      
      <para>
        For example:
      </para>
      
      <para>
        
        <screen>
open-hook \\.gz$ "gzip -cd %f &#62; %t" 
close-hook \\.gz$ "gzip -c %t &#62; %f"
append-hook \\.gz$ "gzip -c %t &#62;&#62; %f" </screen>
        
      </para>
      
      <para>
        You do not have to specify all of the commands. If you omit <link linkend="append-hook">
          append-hook
        </link>
        ,the folder will be open and
        closed again each time you will add to it. If you omit <link linkend="close-hook">
          close-hook
        </link>
        (or give empty command) , the
        folder will be open in the  mode. If you specify <link linkend="append-hook">
          append-hook
        </link>
        though you'll be able to append
        to the folder.
      </para>
      
      <para>
        Note that Mutt-ng will only try to use hooks if the file is not in one
        of
        the accepted formats. In particular, if the file is empty, mutt
        supposes it is not compressed. This is important because it allows the
        use of programs that do not have well defined extensions. Just use
        &quot;.&quot; as a regexp. But this may be surprising if your
        compressing script produces empty files. In this situation, unset <link linkend="save-empty">
          save-empty
        </link>
        ,so that the compressed file
        will be removed if you delete all of the messages.
      </para>
      
      <sect2 id="open-hook">
        <title>Open a compressed mailbox for reading</title>
        
        <para>
          Usage: <literal>open-hook</literal> <emphasis>regexp</emphasis>
          &quot;<emphasis>command</emphasis>&quot;
        </para>
        
        <para>
          The <emphasis>command</emphasis> is the command that can be used for
          opening the
          folders whose names match <emphasis>regexp</emphasis>.
        </para>
        
        <para>
          The <emphasis>command</emphasis> string is the printf-like format
          string, and it
          should accept two parameters: &percnt;f, which is replaced with the
          (compressed) folder name, and &percnt;t which is replaced with the
          name of the temporary folder to which to write.
        </para>
        
        <para>
          &percnt;f and &percnt;t can be repeated any number of times in the
          command string, and all of the entries are replaced with the
          appropriate folder name. In addition, &percnt;&percnt; is replaced by
          &percnt;, as in printf, and any other &percnt;anything is left as is.
        </para>
        
        <para>
          The <emphasis>command</emphasis> should <emphasis role="bold">not</emphasis> remove the original compressed file.
          The <emphasis>command</emphasis> should return non-zero exit status
          if it fails, so
          mutt knows something's wrong.
        </para>
        
        <para>
          Example:
        </para>
        
        <para>
          
          <screen>
open-hook \\.gz$ "gzip -cd %f &#62; %t" 
</screen>
          
        </para>
        
        <para>
          If the <emphasis>command</emphasis> is empty, this operation is
          disabled for this file
          type.
        </para>
        
      </sect2>
      
      <sect2 id="close-hook">
        <title>Write a compressed mailbox</title>
        
        <para>
          Usage: <literal>close-hook</literal> <emphasis>regexp</emphasis>
          &quot;<emphasis>command</emphasis>&quot;
        </para>
        
        <para>
          This is used to close the folder that was open with the <link linkend="open-hook">
            open-hook
          </link>
          command after some changes were made to it.
        </para>
        
        <para>
          The <emphasis>command</emphasis> string is the command that can be
          used for closing the
          folders whose names match <emphasis>regexp</emphasis>. It has the
          same format as in 
          the <link linkend="open-hook">open-hook</link> command. Temporary
          folder
          in this case is the folder previously produced by the &#60;<link linkend="open-hook">
            open-hook
          </link>
          command.
        </para>
        
        <para>
          The <emphasis>command</emphasis> should <emphasis role="bold">not</emphasis> remove the decompressed file. The
          <emphasis>command</emphasis> should return non-zero exit status if it
          fails, so mutt
          knows something's wrong.
        </para>
        
        <para>
          Example:
        </para>
        
        <para>
          
          <screen>
close-hook \\.gz$ "gzip -c %t &#62; %f"</screen>
          
        </para>
        
        <para>
          If the <emphasis>command</emphasis> is empty, this operation is
          disabled for this file
          type, and the file can only be open in the readonly mode.
        </para>
        
        <para>
          <link linkend="close-hook">close-hook</link> is not called when you
          exit
          from the folder if the folder was not changed.
        </para>
        
      </sect2>
      
      <sect2 id="append-hook">
        <title>Append a message to a compressed mailbox</title>
        
        <para>
          Usage: <literal>append-hook</literal> <emphasis>regexp</emphasis>
          &quot;<emphasis>command</emphasis>&quot;
        </para>
        
        <para>
          This command is used for saving to an existing compressed folder.
          The <emphasis>command</emphasis> is the command that can be used for
          appending to the
          folders whose names match <emphasis>regexp</emphasis>. It has the
          same format as in 
          the <link linkend="open-hook">open-hook</link> command.
          The temporary folder in this case contains the messages that are
          beingappended. 
        </para>
        
        <para>
          The <emphasis>command</emphasis> should <emphasis role="bold">not</emphasis> remove the decompressed file. The
          <emphasis>command</emphasis> should return non-zero exit status if it
          fails, so mutt
          knows something's wrong.
        </para>
        
        <para>
          Example:
        </para>
        
        <para>
          
          <screen>
append-hook \\.gz$ "gzip -c %t &#62;&#62; %f" </screen>
          
        </para>
        
        <para>
          When <link linkend="append-hook">append-hook</link> is used, the
          folder is
          not opened, which saves time, but this means that we can not find out
          what the folder type is. Thus the default (<link linkend="mbox-type">
            mbox-type
          </link>
          )type is always supposed (i.e.
          this is the format used for the temporary folder).
        </para>
        
        <para>
          If the file does not exist when you save to it, <link linkend="close-hook">
            close-hook
          </link>
          is called, and not <link linkend="append-hook">append-hook</link>. <link linkend="append-hook">
            append-hook
          </link>
          is only
          for appending to existing folders.
        </para>
        
        <para>
          If the <emphasis>command</emphasis> is empty, this operation is
          disabled for this file
          type. In this case, the folder will be open and closed again (using
          <link linkend="open-hook">open-hook</link> and <link linkend="close-hook">
            close-hook
          </link>
          respectively) each time you will add to it.
        </para>
        
      </sect2>
      
      <sect2>
        <title>Encrypted folders</title>
        
        <para>
          The compressed folders support can also be used to handle encrypted
          folders. If you want to encrypt a folder with PGP, you may want to
          usethe following hooks:
        </para>
        
        <para>
          
          <screen>
open-hook  \\.pgp$ "pgp -f &#60; %f &#62; %t"
close-hook \\.pgp$ "pgp -fe YourPgpUserIdOrKeyId &#60; %t &#62; %f"
</screen>
          
        </para>
        
        <para>
          Please note, that PGP does not support appending to an encrypted
          folder, so there is no append-hook defined.
        </para>
        
        <para>
          <emphasis role="bold">Note:</emphasis> the folder is temporary stored
          decrypted in the /tmp
          directory, where it can be read by your system administrator. So
          thinkabout the security aspects of this.
        </para>
        
        <para>
          
        </para>
        
        <para>
          
        </para>
        
      </sect2>
      
    </sect1>
    
  </chapter>
  
  <chapter>
    <title>Mutt-ng's MIME Support  </title>
    
    <para>
      Quite a bit of effort has been made to make Mutt-ng the premier text-mode
      MIME MUA.  Every effort has been made to provide the functionality that
      the discerning MIME user requires, and the conformance to the standards
      wherever possible.  When configuring Mutt-ng for MIME, there are two
      extratypes of configuration files which Mutt-ng uses.  One is the
      <literal>mime.types</literal> file, which contains the mapping of file
      extensions to 
      IANA MIME types.  The other is the <literal>mailcap</literal> file, which
      specifies
      the external commands to use for handling specific MIME types.
    </para>
    
    <sect1>
      <title>Using MIME in Mutt  </title>
      
      <para>
        There are three areas/menus in Mutt-ng which deal with MIME, they are
        the
        pager (while viewing a message), the attachment menu and the compose
        menu.
      </para>
      
      <sect2>
        <title>Viewing MIME messages in the pager</title>
        
        <para>
          When you select a message from the index and view it in the pager,
          Mutt
          decodes the message to a text representation.  Mutt-ng internally
          supports
          a number of MIME types, including <literal>text/plain, text/enriched,
            message/rfc822, and message/news
          </literal>
          .In addition, the export
          controlled version of Mutt-ng recognizes a variety of PGP MIME types,
          including PGP/MIME and application/pgp.
        </para>
        
        <para>
          Mutt-ng will denote attachments with a couple lines describing them.
          These lines are of the form:
          
          <screen>
[-- Attachment #1: Description --]
[-- Type: text/plain, Encoding: 7bit, Size: 10000 --]</screen>
          
          Where the <literal>Description</literal> is the description or
          filename given for the
          attachment, and the <literal>Encoding</literal> is one of
          <literal>7bit/8bit/quoted-printable/base64/binary</literal>.
        </para>
        
        <para>
          If Mutt-ng cannot deal with a MIME type, it will display a message
          like:
          
          <screen>
[-- image/gif is unsupported (use 'v' to view this part) --]</screen>
          
        </para>
        
      </sect2>
      
      <sect2 id="attach-menu">
        <title>The Attachment Menu</title>
        
        <para>
          The default binding for <literal>view-attachments</literal> is `v',
          which displays the
          attachment menu for a message.  The attachment menu displays a list
          ofthe attachments in a message.  From the attachment menu, you can
          save,
          print, pipe, delete, and view attachments.  You can apply these
          operations to a group of attachments at once, by tagging the
          attachments
          and by using the ``tag-prefix'' operator.  You can also reply to the
          current message from this menu, and only the current attachment (or
          the
          attachments tagged) will be quoted in your reply.  You can view
          attachments as text, or view them using the mailcap viewer
          definition.
        </para>
        
        <para>
          Finally, you can apply the usual message-related functions (like 
          <link linkend="resend-message">resend-message</link>, and the reply
          and forward functions) to attachments of type <literal>message/rfc822</literal>.
        </para>
        
        <para>
          See the help on the attachment menu for more information.
        </para>
        
      </sect2>
      
      <sect2 id="compose-menu">
        <title>The Compose Menu</title>
        
        <para>
          The compose menu is the menu you see before you send a message.  It
          allows you to edit the recipient list, the subject, and other aspects
          of your message.  It also contains a list of the attachments of your
          message, including the main body.  From this menu, you can print,
          copy,
          filter, pipe, edit, compose, review, and rename an attachment or a
          list of tagged attachments.  You can also modifying the attachment
          information, notably the type, encoding and description.
        </para>
        
        <para>
          Attachments appear as follows:
          
          <screen>
1 [text/plain, 7bit, 1K]             /tmp/mutt-euler-8082-0 &#60;no description&#62;
2 [applica/x-gunzip, base64, 422K]   ~/src/mutt-0.85.tar.gz &#60;no description&#62;</screen>
          
        </para>
        
        <para>
          The '-' denotes that Mutt-ng will delete the file after sending (or
          postponing, or canceling) the message.  It can be toggled with the
          <literal>toggle-unlink</literal> command (default: u).  The next
          field is the MIME
          content-type, and can be changed with the <literal>edit-type</literal> command
          (default: &circ;T).  The next field is the encoding for the
          attachment,
          which allows a binary message to be encoded for transmission on 7bit
          links.  It can be changed with the <literal>edit-encoding</literal>
          command
          (default: &circ;E).  The next field is the size of the attachment,
          rounded to kilobytes or megabytes.  The next field is the filename,
          which can be changed with the <literal>rename-file</literal> command
          (default: R).
          The final field is the description of the attachment, and can be
          changed with the <literal>edit-description</literal> command
          (default: d).
        </para>
        
        <para>
          
        </para>
        
      </sect2>
      
    </sect1>
    
    <sect1>
      <title>
        MIME Type configuration with <literal>mime.types</literal>  
      </title>
      
      <para>
        When you add an attachment to your mail message, Mutt-ng searches your
        personal mime.types file at <literal>
          &dollar;&lcub;HOME&rcub;/.mime.types
        </literal>
        ,and then
        the system mime.types file at <literal>/usr/local/share/mutt/mime.types</literal> or
        <literal>/etc/mime.types</literal>
      </para>
      
      <para>
        The mime.types file consist of lines containing a MIME type and a space
        separated list of extensions.  For example:
        
        <screen>
application/postscript          ps eps
application/pgp                 pgp
audio/x-aiff                    aif aifc aiff</screen>
        
        A sample <literal>mime.types</literal> file comes with the Mutt-ng
        distribution, and
        should contain most of the MIME types you are likely to use.  
      </para>
      
      <para>
        If Mutt-ng can not determine the mime type by the extension of the file
        you
        attach, it will look at the file.  If the file is free of binary
        information, Mutt-ng will assume that the file is plain text, and mark
        it
        as <literal>text/plain</literal>.  If the file contains binary
        information, then Mutt-ng will
        mark it as <literal>application/octet-stream</literal>.  You can change
        the MIME
        type that Mutt-ng assigns to an attachment by using the <literal>
          edit-type
        </literal>
        command from the compose menu (default: &circ;T). The MIME type is
        actually a
        major mime type followed by the sub-type, separated by a '/'. 6 major
        types: application, text, image, video, audio, and model have been
        approved
        after various internet discussions. Mutt-ng recognises all of these if
        the 
        appropriate entry is found in the mime.types file. It also recognises
        other
        major mime types, such as the chemical type that is widely used in the 
        molecular modelling community to pass molecular data in various forms
        to 
        various molecular viewers. Non-recognised mime types should only be
        used 
        if the recipient of the message is likely to be expecting such
        attachments.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1>
      <title>
        MIME Viewer configuration with <literal>mailcap</literal>  
      </title>
      
      <para>
        Mutt-ng supports RFC 1524 MIME Configuration, in particular the Unix
        specific format specified in Appendix A of RFC 1524.  This file format
        is commonly referred to as the mailcap format.  Many MIME compliant
        programs utilize the mailcap format, allowing you to specify handling
        for all MIME types in one place for all programs.  Programs known to
        use this format include Netscape, XMosaic, lynx and metamail.
      </para>
      
      <para>
        In order to handle various MIME types that Mutt-ng can not handle
        internally, Mutt-ng parses a series of external configuration files to
        find an external handler.  The default search string for these files
        is a colon delimited list set to
        
        <screen>
${HOME}/.mailcap:/usr/local/share/mutt/mailcap:/etc/mailcap:/etc/mailcap:/usr/etc/mailcap:/usr/local/etc/mailcap</screen>
        
        where <literal>&dollar;HOME</literal> is your home directory.
      </para>
      
      <para>
        In particular, the metamail distribution will install a mailcap file,
        usually as <literal>/usr/local/etc/mailcap</literal>, which contains
        some baseline
        entries.
      </para>
      
      <sect2>
        <title>The Basics of the mailcap file</title>
        
        <para>
          A mailcap file consists of a series of lines which are comments,
          blank,
          or definitions.
        </para>
        
        <para>
          A comment line consists of a &num; character followed by anything you
          want.
        </para>
        
        <para>
          A blank line is blank.
        </para>
        
        <para>
          A definition line consists of a content type, a view command, and any
          number of optional fields.  Each field of a definition line is
          dividedby a semicolon ';' character.
        </para>
        
        <para>
          The content type is specified in the MIME standard type/subtype
          method.
          For example,
          <literal>text/plain, text/html, image/gif, </literal>
          etc.  In addition, the mailcap format includes two formats for
          wildcards, one using the special '*' subtype, the other is the
          implicit
          wild, where you only include the major type.  For example, <literal>
            image/*
          </literal>
          ,or
          <literal>video,</literal> will match all image types and video types,
          respectively.
        </para>
        
        <para>
          The view command is a Unix command for viewing the type specified.
          There
          are two different types of commands supported. The default is to send
          the body of the MIME message to the command on stdin. You can change
          this behavior by using &percnt;s as a parameter to your view command.
          This will cause Mutt-ng to save the body of the MIME message to a
          temporary
          file, and then call the view command with the &percnt;s replaced by
          the name of the temporary file. In both cases, Mutt-ng will turn over
          the
          terminal to the view program until the program quits, at which time
          Mutt
          will remove the temporary file if it exists.
        </para>
        
        <para>
          So, in the simplest form, you can send a text/plain message to the
          external pager more on stdin:
          
          <screen>
text/plain; more</screen>
          
          Or, you could send the message as a file:
          
          <screen>
text/plain; more %s</screen>
          
          Perhaps you would like to use lynx to interactively view a text/html 
          message:
          
          <screen>
text/html; lynx %s</screen>
          
          In this case, lynx does not support viewing a file from stdin, so you
          must use the &percnt;s syntax.
          <emphasis role="bold">Note:</emphasis> <emphasis>Some older versions
            of lynx contain a bug where they
            will check the mailcap file for a viewer for text/html.  They will
            find
            the line which calls lynx, and run it.  This causes lynx to
            continuously
            spawn itself to view the object.
          </emphasis>
        </para>
        
        <para>
          On the other hand, maybe you don't want to use lynx interactively,
          youjust want to have it convert the text/html to text/plain, then you
          can
          use:
          
          <screen>
text/html; lynx -dump %s | more</screen>
          
        </para>
        
        <para>
          Perhaps you wish to use lynx to view text/html files, and a pager on
          all other text formats, then you would use the following:
          
          <screen>
text/html; lynx %s
text/*; more</screen>
          
          This is the simplest form of a mailcap file.
        </para>
        
      </sect2>
      
      <sect2>
        <title>Secure use of mailcap</title>
        
        <para>
          The interpretation of shell meta-characters embedded in MIME
          parameters
          can lead to security problems in general.  Mutt-ng tries to quote
          parameters
          in expansion of &percnt;s syntaxes properly, and avoids risky
          characters by
          substituting them, see the <link linkend="mailcap-sanitize">
            mailcap-sanitize
          </link>
          variable.
        </para>
        
        <para>
          Although mutt's procedures to invoke programs with mailcap seem to be
          safe, there are other applications parsing mailcap, maybe taking less
          care
          of it.  Therefore you should pay attention to the following rules:
        </para>
        
        <para>
          <emphasis>Keep the &percnt;-expandos away from shell quoting.</emphasis>
          Don't quote them with single or double quotes.  Mutt-ng does this for
          you, the right way, as should any other program which interprets
          mailcap.  Don't put them into backtick expansions.  Be highly careful
          with eval statements, and avoid them if possible at all.  Trying to
          fix
          broken behaviour with quotes introduces new leaks - there is no
          alternative to correct quoting in the first place.
        </para>
        
        <para>
          If you have to use the &percnt;-expandos' values in context where you
          need
          quoting or backtick expansions, put that value into a shell variable
          and reference the shell variable where necessary, as in the following
          example (using <literal>&dollar;charset</literal> inside the backtick
          expansion is safe,
          since it is not itself subject to any further expansion):
        </para>
        
        <para>
          
          <screen>
text/test-mailcap-bug; cat %s; copiousoutput; test=charset=%{charset} \
&#38;&#38; test "`echo $charset | tr '[A-Z]' '[a-z]'`" != iso-8859-1</screen>
          
        </para>
        
      </sect2>
      
      <sect2>
        <title>Advanced mailcap Usage</title>
        
        <sect3>
          <title>Optional Fields</title>
          
          <para>
            In addition to the required content-type and view command fields,
            you
            can add semi-colon ';' separated fields to set flags and other
            options.
            Mutt-ng recognizes the following optional fields:
            <variablelist>
              
              <varlistentry>
                <term>copiousoutput</term>
                <listitem>
                  <para>
                    This flag tells Mutt-ng that the command passes possibly
                    large amounts of
                    text on stdout.  This causes Mutt-ng to invoke a pager
                    (either the internal
                    pager or the external pager defined by the pager variable)
                    on the output
                    of the view command.  Without this flag, Mutt-ng assumes
                    that the command
                    is interactive.  One could use this to replace the pipe to <literal>
                      more
                    </literal>
                    in the <literal>lynx -dump</literal> example in the Basic
                    section:
                    
                    <screen>
text/html; lynx -dump %s ; copiousoutput</screen>
                    
                    This will cause lynx to format the text/html output as
                    text/plain
                    and Mutt-ng will use your standard pager to display the
                    results.
                  </para>
                </listitem>
              </varlistentry>
              <varlistentry>
                <term>needsterminal</term>
                <listitem>
                  <para>
                    Mutt-ng uses this flag when viewing attachments with <link linkend="auto-view">
                      auto-view
                    </link>
                    ,in order to decide whether it should honor the setting
                    of the <link linkend="wait-key">wait-key</link> variable or
                    not.  When an attachment is viewed using an interactive
                    program, and the
                    corresponding mailcap entry has a <emphasis>needsterminal</emphasis> flag, Mutt-ng will use
                    <link linkend="wait-key">wait-key</link> and the exit
                    statusof the program to decide if it will ask you to press
                    a key after the
                    external program has exited.  In all other situations it
                    will not prompt
                    you for a key.
                  </para>
                </listitem>
              </varlistentry>
              <varlistentry>
                <term>compose=&lt;command&gt;</term>
                <listitem>
                  <para>
                    This flag specifies the command to use to create a new
                    attachment of a
                    specific MIME type.  Mutt-ng supports this from the compose
                    menu.
                  </para>
                </listitem>
              </varlistentry>
              <varlistentry>
                <term>composetyped=&lt;command&gt;</term>
                <listitem>
                  <para>
                    This flag specifies the command to use to create a new
                    attachment of a
                    specific MIME type.  This command differs from the compose
                    command in
                    that mutt will expect standard MIME headers on the data. 
                    This can be
                    used to specify parameters, filename, description, etc. for
                    a new
                    attachment.   Mutt-ng supports this from the compose menu.
                  </para>
                </listitem>
              </varlistentry>
              <varlistentry>
                <term>print=&lt;command&gt;</term>
                <listitem>
                  <para>
                    This flag specifies the command to use to print a specific
                    MIME type.
                    Mutt-ng supports this from the attachment and compose
                    menus.
                  </para>
                </listitem>
              </varlistentry>
              <varlistentry>
                <term>edit=&lt;command&gt;</term>
                <listitem>
                  <para>
                    This flag specifies the command to use to edit a specific
                    MIME type.  
                    Mutt-ng supports this from the compose menu, and also uses
                    it to compose
                    new attachments.  Mutt-ng will default to the defined
                    editor for text
                    attachments.
                  </para>
                </listitem>
              </varlistentry>
              <varlistentry>
                <term>nametemplate=&lt;template&gt;</term>
                <listitem>
                  <para>
                    This field specifies the format for the file denoted by
                    &percnt;s in the
                    command fields.  Certain programs will require a certain
                    file extension,
                    for instance, to correctly view a file.  For instance, lynx
                    will only
                    interpret a file as <literal>text/html</literal> if the
                    file ends in <literal>.html</literal>.
                    So, you would specify lynx as a <literal>text/html</literal> viewer with a line in
                    the mailcap file like:
                    
                    <screen>
text/html; lynx %s; nametemplate=%s.html</screen>
                    
                  </para>
                </listitem>
              </varlistentry>
              <varlistentry>
                <term>test=&lt;command&gt;</term>
                <listitem>
                  <para>
                    This field specifies a command to run to test whether this
                    mailcap
                    entry should be used.  The command is defined with the
                    command expansion
                    rules defined in the next section.  If the command returns
                    0, then the
                    test passed, and Mutt-ng uses this entry.  If the command
                    returns non-zero,
                    then the test failed, and Mutt-ng continues searching for
                    the right entry.
                    <emphasis role="bold">Note:</emphasis> <emphasis>the
                      content-type must match before Mutt-ng performs the test.
                    </emphasis>
                    For example:
                    
                    <screen>
text/html; netscape -remote 'openURL(%s)' ; test=RunningX
text/html; lynx %s</screen>
                    
                    In this example, Mutt-ng will run the program RunningX
                    which will return 0
                    if the X Window manager is running, and non-zero if it
                    isn't.  If
                    RunningX returns 0, then Mutt-ng will call netscape to
                    display the
                    text/html object.  If RunningX doesn't return 0, then
                    Mutt-ng will go on
                    to the next entry and use lynx to display the text/html
                    object.
                  </para>
                </listitem>
              </varlistentry>
            </variablelist>
          </para>
          
        </sect3>
        
        <sect3>
          <title>Search Order</title>
          
          <para>
            When searching for an entry in the mailcap file, Mutt-ng will
            search for
            the most useful entry for its purpose.  For instance, if you are
            attempting to print an <literal>image/gif</literal>, and you have
            the following
            entries in your mailcap file, Mutt-ng will search for an entry with
            the
            print command:
            
            <screen>
image/*;        xv %s
image/gif;      ; print= anytopnm %s | pnmtops | lpr; \
nametemplate=%s.gif</screen>
            
            Mutt-ng will skip the <literal>image/*</literal> entry and use the <literal>
              image/gif
            </literal>
            entry with the print command.
          </para>
          
          <para>
            In addition, you can use this with <link linkend="auto-view">
              auto-view
            </link>
            to denote two commands for viewing an attachment, one to be viewed
            automatically, the other to be viewed interactively from the
            attachment
            menu.  In addition, you can then use the test feature to determine
            which
            viewer to use interactively depending on your environment.
            
            <screen>
text/html;      netscape -remote 'openURL(%s)' ; test=RunningX
text/html;      lynx %s; nametemplate=%s.html
text/html;      lynx -dump %s; nametemplate=%s.html; copiousoutput</screen>
            
            For <link linkend="auto-view">auto-view</link>, Mutt-ng will choose
            the third
            entry because of the copiousoutput tag.  For interactive viewing,
            Mutt
            will run the program RunningX to determine if it should use the
            first
            entry.  If the program returns non-zero, Mutt-ng will use the
            second entry
            for interactive viewing.
          </para>
          
        </sect3>
        
        <sect3>
          <title>Command Expansion</title>
          
          <para>
            The various commands defined in the mailcap files are passed to the
            <literal>/bin/sh</literal> shell using the system() function. 
            Before the
            command is passed to <literal>/bin/sh -c</literal>, it is parsed to
            expand
            various special parameters with information from Mutt-ng.  The
            keywords
            Mutt-ng expands are:
            <variablelist>
              
              <varlistentry>
                <term>&percnt;s</term>
                <listitem>
                  <para>
                    As seen in the basic mailcap section, this variable is
                    expanded
                    to a filename specified by the calling program.  This file
                    contains
                    the body of the message to view/print/edit or where the
                    composing
                    program should place the results of composition.  In
                    addition, the
                    use of this keyword causes Mutt-ng to not pass the body of
                    the message
                    to the view/print/edit program on stdin.
                  </para>
                </listitem>
              </varlistentry>
              <varlistentry>
                <term>&percnt;t</term>
                <listitem>
                  <para>
                    Mutt-ng will expand &percnt;t to the text representation of
                    the content
                    type of the message in the same form as the first parameter
                    of the
                    mailcap definition line, ie <literal>text/html</literal> or
                    <literal>image/gif</literal>.
                  </para>
                </listitem>
              </varlistentry>
              <varlistentry>
                <term>&percnt;&lcub;&lt;parameter&gt;&rcub;</term>
                <listitem>
                  <para>
                    Mutt-ng will expand this to the value of the specified
                    parameter
                    from the Content-Type: line of the mail message.  For
                    instance, if
                    Your mail message contains:
                    
                    <screen>
Content-Type: text/plain; charset=iso-8859-1</screen>
                    
                    then Mutt-ng will expand &percnt;&lcub;charset&rcub; to
                    iso-8859-1.  The default metamail
                    mailcap file uses this feature to test the charset to spawn
                    an xterm
                    using the right charset to view the message.
                  </para>
                </listitem>
              </varlistentry>
              <varlistentry>
                <term>&bsol;&percnt;</term>
                <listitem>
                  <para>
                    This will be replaced by a &percnt;
                  </para>
                </listitem>
              </varlistentry>
            </variablelist>
            Mutt-ng does not currently support the &percnt;F and &percnt;n
            keywords
            specified in RFC 1524.  The main purpose of these parameters is for
            multipart messages, which is handled internally by Mutt-ng.
          </para>
          
        </sect3>
        
      </sect2>
      
      <sect2>
        <title>Example mailcap files</title>
        
        <para>
          This mailcap file is fairly simple and standard:
          
          <screen>>
# I'm always running X :)
video/*;        xanim %s &#62; /dev/null
image/*;        xv %s &#62; /dev/null

# I'm always running netscape (if my computer had more memory, maybe)
text/html;      netscape -remote 'openURL(%s)'</screen>
          
        </para>
        
        <para>
          This mailcap file shows quite a number of examples:
        </para>
        
        <para>
          
          <screen>
# Use xanim to view all videos   Xanim produces a header on startup,
# send that to /dev/null so I don't see it
video/*;        xanim %s &#62; /dev/null

# Send html to a running netscape by remote
text/html;      netscape -remote 'openURL(%s)'; test=RunningNetscape
# If I'm not running netscape but I am running X, start netscape on the
# object
text/html;      netscape %s; test=RunningX

# Else use lynx to view it as text
text/html;      lynx %s

# This version would convert the text/html to text/plain
text/html;      lynx -dump %s; copiousoutput

# I use enscript to print text in two columns to a page
text/*;         more %s; print=enscript -2Gr %s

# Netscape adds a flag to tell itself to view jpegs internally
image/jpeg;xv %s; x-mozilla-flags=internal

# Use xv to view images if I'm running X
# In addition, this uses the \ to extend the line and set my editor
# for images
image/*;xv %s; test=RunningX; edit=xpaint %s

# Convert images to text using the netpbm tools
image/*;  (anytopnm %s | pnmscale -xysize 80 46 | ppmtopgm | pgmtopbm |
pbmtoascii -1x2 ) 2&#62;&#38;1 ; copiousoutput

# Send excel spreadsheets to my NT box
application/ms-excel; open.pl %s</screen>
          
        </para>
        
        <para>
          
        </para>
        
      </sect2>
      
    </sect1>
    
    <sect1 id="auto-view">
      <title>MIME Autoview  </title>
      
      <para>
        In addition to explicitly telling Mutt-ng to view an attachment with
        theMIME viewer defined in the mailcap file, Mutt-ng has support for
        automatically viewing MIME attachments while in the pager.
      </para>
      
      <para>
        To work, you must define a viewer in the mailcap file which uses the 
        <literal>copiousoutput</literal> option to denote that it is
        non-interactive.
        Usually, you also use the entry to convert the attachment to a text
        representation which you can view in the pager.
      </para>
      
      <para>
        You then use the <literal>auto&lowbar;view</literal> muttrc command to
        list the
        content-types that you wish to view automatically.
      </para>
      
      <para>
        For instance, if you set auto&lowbar;view to:
        
        <screen>
auto_view text/html application/x-gunzip application/postscript
image/gif application/x-tar-gz</screen>
        
      </para>
      
      <para>
        Mutt-ng could use the following mailcap entries to automatically view
        attachments of these types.
        
        <screen>
text/html;      lynx -dump %s; copiousoutput; nametemplate=%s.html
image/*;        anytopnm %s | pnmscale -xsize 80 -ysize 50 | ppmtopgm | pgmtopbm | pbmtoascii ; copiousoutput
application/x-gunzip;   gzcat; copiousoutput
application/x-tar-gz; gunzip -c %s | tar -tf - ; copiousoutput
application/postscript; ps2ascii %s; copiousoutput</screen>
        
      </para>
      
      <para>
        ``unauto&lowbar;view'' can be used to remove previous entries from the
        autoview list.
        This can be used with message-hook to autoview messages based on size,
        etc.
        ``unauto&lowbar;view *'' will remove all previous entries.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="alternative-order">
      <title>MIME Multipart/Alternative  </title>
      
      <para>
        Mutt-ng has some heuristics for determining which attachment of a
        multipart/alternative type to display.  First, mutt will check the 
        alternative&lowbar;order list to determine if one of the available
        typesis preferred.  The alternative&lowbar;order list consists of a
        number of
        MIME types in order, including support for implicit and explicit
        wildcards, for example:
        
        <screen>
alternative_order text/enriched text/plain text
application/postscript image/*</screen>
        
      </para>
      
      <para>
        Next, mutt will check if any of the types have a defined 
        <link linkend="auto-view">auto-view</link>, and use that.  Failing
        that, Mutt-ng will look for any text type.  As a last attempt, mutt
        willlook for any type it knows how to handle.
      </para>
      
      <para>
        To remove a MIME type from the <literal>alternative&lowbar;order</literal> list, use the
        <literal>unalternative&lowbar;order</literal> command.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="mime-lookup">
      <title>MIME Lookup  </title>
      
      <para>
        Mutt-ng's mime&lowbar;lookup list specifies a list of mime-types that
        should not
        be treated according to their mailcap entry.  This option is designed
        todeal with binary types such as application/octet-stream.  When an
        attachment's
        mime-type is listed in mime&lowbar;lookup, then the extension of the
        filename will
        be compared to the list of extensions in the mime.types file.  The
        mime-type
        associated with this extension will then be used to process the
        attachment
        according to the rules in the mailcap file and according to any other
        configuration
        options (such as auto&lowbar;view) specified.  Common usage would be:
        
        <screen>
mime_lookup application/octet-stream application/X-Lotus-Manuscript</screen>
        
      </para>
      
      <para>
        In addition, the unmime&lowbar;lookup command may be used to disable
        this feature
        for any particular mime-type if it had been set, for example, in a
        global
        muttrc.
      </para>
      
      <para>
        
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
  </chapter>
  
  <chapter>
    <title>Security Considerations    </title>
    
    <para>
      First of all, mutt-ng contains no security holes included by
      intention but may contain unknown security holes. As a consequence,
      please run mutt-ng only with as few permissions as possible.
    </para>
    
    <para>
      Please do not run mutt-ng as the super user.
    </para>
    
    <para>
      When configuring mutt-ng, there're some points to note about secure
      setups.
    </para>
    
    <para>
      In practice, mutt-ng can be easily made as vulnerable as even the
      most insecure mail user agents (in their default configuration) just
      by changing mutt-ng's configuration files: it then can execute
      arbitrary programs and scripts attached to messages, send out private
      data on its own, etc. Although this is not believed to the common type
      of setup, please read this chapter carefully.
    </para>
    
    <sect1>
      <title>Passwords      </title>
      
      <para>
        Although mutt-ng can be told the various passwords for accounts,
        please never store passwords in configuration files. Besides the
        fact that the system's operator can always read them, you could
        forget to replace the actual password with asterisks when reporting
        a bug or asking for help via, for example, a mailing list so that
        your mail including your password could be archived by internet
        search engines, etc. Please never store passwords on disk.
      </para>
      
    </sect1>
    
    <sect1>
      <title>Temporary Files      </title>
      
      <para>
        Mutt-ng uses many temporary files for viewing messages, verifying
        digital signatures, etc. The <link linkend="umask">umask</link>
        variable can be used to change the default permissions of these
        files. Please only change it if you really know what you are doing.
        Also, a different location for these files may be desired which can
        be changed via the <link linkend="tmpdir">tmpdir</link> variable.
      </para>
      
    </sect1>
    
    <sect1>
      <title>Information Leaks    </title>
      
      <sect2>
        <title>Message-ID: headers      </title>
        
        <para>
          In the default configuration, mutt-ng will leak some information
          to the outside world when sending messages: the generation of
          <literal>Message-ID:</literal> headers includes a step counter which
          is increased
          (and rotated) with every message sent. If you'd like to hide this
          information probably telling others how many mail you sent in which
          time, you at least need to remove the <literal>&percnt;P</literal>
          expando from the
          default setting of the <link linkend="msgid-format">msgid-format</link> variable. Please make sure that
          you really know how local parts of these <literal>Message-ID:</literal> headers
          are composed.
        </para>
        
      </sect2>
      
      <sect2>
        <title>mailto:-style links      </title>
        
        <para>
          As mutt-ng be can be set up to be the mail client to handle
          <literal>mailto:</literal> style links in websites, there're security
          considerations, too. To keep the old behavior by default, mutt-ng
          will be strict in interpreting them which means that arbitrary
          header fields can be embedded in these links which could override
          existing header fields or attach arbitrary files. This may be
          problematic if the <link linkend="edit-headers">edit-headers</link>
          variable is <emphasis>unset</emphasis>, i.e. the
          user doesn't want to see header fields while editing the message.
        </para>
        
        <para>
          For example, following a link like
        </para>
        
        <para>
          
          <screen>
mailto:joe@host?Attach=~/.gnupg/secring.gpg</screen>
          
        </para>
        
        <para>
          will send out the user's private gnupg keyring to <literal>joe@host</literal> if
          the user doesn't follow the information on screen carefully
          enough.
        </para>
        
        <para>
          When <emphasis>unsetting</emphasis> the <link linkend="strict-mailto">
            strict-mailto
          </link>
          variable, mutt-ng will
        </para>
        
        <para>
          
          <itemizedlist>
            <listitem>
              
              <para>
                be less strict when interpreting these links by
                prepending a <literal>X-Mailto-</literal> string to all header
                fields
                embedded in such a link <emphasis>and</emphasis>
                
              </para>
            </listitem>
            <listitem>
              
              <para>
                turn on the <link linkend="edit-headers">edit-headers</link>
                variable by
                force to let the user see all the headers
                (because they still may leak information.)
                
              </para>
            </listitem>
            
          </itemizedlist>
          
        </para>
        
      </sect2>
      
    </sect1>
    
    <sect1>
      <title>External applications      </title>
      
      <para>
        Mutt-ng in many places has to rely on external applications or
        for convenience supports mechanisms involving external
        applications.
      </para>
      
      <sect2>
        <title>mailcap        </title>
        
        <para>
          One of these is the <literal>mailcap</literal> mechanism as defined
          by RfC
          1524. Mutt-ng can be set up to <emphasis>automatically</emphasis>
          execute any
          given utility as listed in one of the mailcap files (see the
          <link linkend="mailcap-path">mailcap-path</link>
          variable for details.) 
        </para>
        
        <para>
          These utilities may have a variety of security vulnerabilities,
          including overwriting of arbitrary files, information leaks or
          other exploitable bugs.  These vulnerabilities may go unnoticed by
          the user, especially when they are called automatically (and
          without interactive prompting) from the mailcap file(s). When
          using mutt-ng's autoview mechanism in combination with mailcap
          files, please be sure to...
        </para>
        
        <para>
          
          <itemizedlist>
            <listitem>
              
              <para>
                manually select trustworth applications with a reasonable
                calling sequence
                
              </para>
            </listitem>
            <listitem>
              
              <para>
                periodically check the contents of mailcap files,
                especially after software installations or upgrades
                
              </para>
            </listitem>
            <listitem>
              
              <para>
                keep the software packages referenced in the mailcap file up to
                date
                
              </para>
            </listitem>
            <listitem>
              
              <para>
                leave the <link linkend="mailcap-sanitize">mailcap-sanitize</link> variable in its default
                state to restrict mailcap expandos to a safe set of characters
                
              </para>
            </listitem>
            
          </itemizedlist>
          
        </para>
        
      </sect2>
      
      <sect2>
        <title>Other        </title>
        
        <para>
          Besides the mailcap mechanism, mutt-ng uses a number of other
          external utilities for operation.
        </para>
        
        <para>
          The same security considerations apply for these as for tools
          involved via mailcap (for example, mutt-ng is vulnerable to Denial
          of Service Attacks with compressed folders support if the
          uncompressed mailbox is too large for the disk it is saved to.)
        </para>
        
        <para>
          As already noted, most of these problems are not built in but
          caused by wrong configuration, so please check your configuration.
        </para>
        
      </sect2>
      
    </sect1>
    
  </chapter>
  
  <chapter>
    <title>Reference  </title>
    
    <sect1 id="commandline">
      <title>Command line options  </title>
      
      <para>
        Running <literal>mutt</literal> with no arguments will make Mutt-ng
        attempt to read your spool
        mailbox.  However, it is possible to read other mailboxes and
        to send messages from the command line as well.
      </para>
      
      <para>
        
        <table>
          <title>Mutt-NG Command Line Options</title>
          <tgroup cols="2" align="left" colsep="1" rowsep="1">
          <thead>
            <row>
              <entry>Option</entry>
              <entry>Description</entry>
            </row>
          </thead>
          <tbody>
            <row><entry><code>-A   </code></entry><entry>expand an alias</entry></row>
            <row><entry><code>-a  </code></entry><entry>attach a file to a message</entry></row>
            <row><entry><code>-b  </code></entry><entry>specify a blind carbon-copy (BCC) address</entry></row>
            <row><entry><code>-c   </code></entry><entry>specify a carbon-copy (Cc) address</entry></row>
            <row><entry><code>-e  </code></entry><entry>specify a config command to be run after initialization files are read</entry></row>
            <row><entry><code>-f   </code></entry><entry>specify a mailbox to load</entry></row>
            <row><entry><code>-F   </code></entry><entry>specify an alternate file to read initialization commands</entry></row>
            <row><entry><code>-h   </code></entry><entry>print help on command line options</entry></row>
            <row><entry><code>-H   </code></entry><entry>specify a draft file from which to read a header and body</entry></row>
            <row><entry><code>-i   </code></entry><entry>specify a file to include in a message composition</entry></row>
            <row><entry><code>-m   </code></entry><entry>specify a default mailbox type</entry></row>
            <row><entry><code>-n   </code></entry><entry>do not read the system Muttngrc</entry></row>
            <row><entry><code>-p   </code></entry><entry>recall a postponed message</entry></row>
            <row><entry><code>-Q   </code></entry><entry>query a configuration variable</entry></row>
            <row><entry><code>-R   </code></entry><entry>open mailbox in read-only mode</entry></row>
            <row><entry><code>-s   </code></entry><entry>specify a subject (enclose in quotes if it contains spaces)</entry></row>
            <row><entry><code>-t    </code></entry><entry>dump the value of all variables to stdout</entry></row>
            <row><entry><code>-T   </code></entry><entry>dump the value of all changed variables to stdout</entry></row>
            <row><entry><code>-v   </code></entry><entry>show version number and compile-time definitions</entry></row>
            <row><entry><code>-x   </code></entry><entry>simulate the mailx(1) compose mode</entry></row>
            <row><entry><code>-y    </code></entry><entry>show a menu containing the files specified by the mailboxes command</entry></row>
            <row><entry><code>-z    </code></entry><entry>exit immediately if there are no messages in the mailbox</entry></row>
            <row><entry><code>-Z   </code></entry><entry>open the first folder with new message,exit immediately if none</entry></row>
          </tbody>
        </tgroup>
      </table>

      </para>
      
      <para>
        To read messages in a mailbox
      </para>
      
      <para>
        <literal>mutt</literal> &lsqb; -nz &rsqb; &lsqb; -F <emphasis>muttrc</emphasis> &rsqb; &lsqb; -m <emphasis>
          type
        </emphasis>
        &rsqb; &lsqb; -f <emphasis>mailbox</emphasis> &rsqb; 
      </para>
      
      <para>
        To compose a new message
      </para>
      
      <para>
        <literal>mutt</literal> &lsqb; -n &rsqb; &lsqb; -F <emphasis>muttrc</emphasis> &rsqb; &lsqb; -a <emphasis>
          file
        </emphasis>
        &rsqb; &lsqb; -c <emphasis>address</emphasis> &rsqb; &lsqb; -i <emphasis>
          filename
        </emphasis>
        &rsqb; &lsqb; -s <emphasis>subject</emphasis> &rsqb; <emphasis>address</emphasis> &lsqb; <emphasis>
          address
        </emphasis>
        ... &rsqb; 
      </para>
      
      <para>
        Mutt-ng also supports a ``batch'' mode to send prepared messages. 
        Simply redirect
        input from the file you wish to send.  For example,
      </para>
      
      <para>
        <literal>mutt -s &quot;data set for run &num;2&quot;
          professor@bigschool.edu
          &lt; &tilde;/run2.dat
        </literal>
      </para>
      
      <para>
        This command will send a message to ``professor@bigschool.edu'' with a
        subject
        of ``data set for run &num;2''.  In the body of the message will be the
        contents
        of the file ``&tilde;/run2.dat''.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="patterns">
      <title>Patterns  </title>

      <para>

        <table>
          <title>Patterns</title>
          <tgroup cols="2" align="left" colsep="1" rowsep="1">
          <thead>
            <row>
              <entry>Pattern Modifier</entry>
              <entry>Argument</entry>
              <entry>Description</entry>
            </row>
          </thead>
          <tbody>
            <row><entry><code>~A </code></entry><entry><code></code></entry><entry>all messages</entry></row>
            <row><entry><code>~b </code></entry><entry><code>EXPR      </code></entry><entry>messages which contain EXPR in the message body</entry></row>
            <row><entry><code>~B </code></entry><entry><code>EXPR        </code></entry><entry>messages which contain EXPR in the whole message</entry></row>
            <row><entry><code>~c </code></entry><entry><code>EXPR       </code></entry><entry>messages carbon-copied to EXPR</entry></row>
            <row><entry><code>~C </code></entry><entry><code>EXPR       </code></entry><entry>message is either to: or cc: EXPR</entry></row>
            <row><entry><code>~D </code></entry><entry><code></code></entry><entry>deleted messages</entry></row>
            <row><entry><code>~d </code></entry><entry><code>[MIN]-[MAX] </code></entry><entry>messages with ``date-sent'' in a Date range</entry></row>
            <row><entry><code>~E </code></entry><entry><code></code></entry><entry>expired messages</entry></row>
            <row><entry><code>~e </code></entry><entry><code>EXPR       </code></entry><entry>message which contains EXPR in the ``Sender'' field</entry></row>
            <row><entry><code>~F </code></entry><entry><code></code></entry><entry>flagged messages</entry></row>
            <row><entry><code>~f </code></entry><entry><code>EXPR       </code></entry><entry>messages originating from EXPR</entry></row>
            <row><entry><code>~g </code></entry><entry><code></code></entry><entry>cryptographically signed messages</entry></row>
            <row><entry><code>~G </code></entry><entry><code></code></entry><entry>cryptographically encrypted messages</entry></row>
            <row><entry><code>~H </code></entry><entry><code>EXPR       </code></entry><entry>messages with a spam attribute matching EXPR</entry></row>
            <row><entry><code>~h </code></entry><entry><code>EXPR       </code></entry><entry>messages which contain EXPR in the message header</entry></row>
            <row><entry><code>~k </code></entry><entry><code></code></entry><entry>message contains PGP key material</entry></row>
            <row><entry><code>~i </code></entry><entry><code>EXPR         </code></entry><entry>message which match ID in the ``Message-ID'' field</entry></row>
            <row><entry><code>~L </code></entry><entry><code>EXPR       </code></entry><entry>message is either originated or received by EXPR</entry></row>
            <row><entry><code>~l </code></entry><entry><code></code></entry><entry>message is addressed to a known mailing list</entry></row>
            <row><entry><code>~m </code></entry><entry><code>[MIN]-[MAX] </code></entry><entry>message in the range MIN to MAX *)</entry></row>
            <row><entry><code>~M </code></entry><entry><code></code></entry><entry>multipart messages</entry></row>
            <row><entry><code>~n </code></entry><entry><code>[MIN]-[MAX] </code></entry><entry>messages with a score in the range MIN to MAX *)</entry></row>
            <row><entry><code>~N </code></entry><entry><code></code></entry><entry>new messages</entry></row>
            <row><entry><code>~O </code></entry><entry><code></code></entry><entry>old messages</entry></row>
            <row><entry><code>~p </code></entry><entry><code></code></entry><entry>message is addressed to you (consults alternates)</entry></row>
            <row><entry><code>~P </code></entry><entry><code></code></entry><entry>message is from you (consults alternates)</entry></row>
            <row><entry><code>~Q </code></entry><entry><code></code></entry><entry>messages which have been replied to</entry></row>
            <row><entry><code>~R </code></entry><entry><code></code></entry><entry>read messages</entry></row>
            <row><entry><code>~r </code></entry><entry><code>[MIN]-[MAX] </code></entry><entry>messages with ``date-received'' in a Date range</entry></row>
            <row><entry><code>~S </code></entry><entry><code></code></entry><entry>superseded messages</entry></row>
            <row><entry><code>~s </code></entry><entry><code>EXPR    </code></entry><entry>messages having EXPR in the ``Subject'' field.</entry></row>
            <row><entry><code>~T </code></entry><entry><code></code></entry><entry>tagged messages</entry></row>
            <row><entry><code>~t </code></entry><entry><code>EXPR       </code></entry><entry>messages addressed to EXPR</entry></row>
            <row><entry><code>~U </code></entry><entry><code></code></entry><entry>unread messages</entry></row>
            <row><entry><code>~u </code></entry><entry><code></code></entry><entry>message is addressed to a subscribed mailing list</entry></row>
            <row><entry><code>~v </code></entry><entry><code></code></entry><entry>message is part of a collapsed thread.</entry></row>
            <row><entry><code>~V </code></entry><entry><code></code></entry><entry>cryptographically verified messages</entry></row>
            <row><entry><code>~w </code></entry><entry><code>EXPR    </code></entry><entry>messages which contain EXPR in the `Newsgroups' field (if compiled with NNTP support)</entry></row>
            <row><entry><code>~x </code></entry><entry><code>EXPR  </code></entry><entry>messages which contain EXPR in the `References' field</entry></row>
            <row><entry><code>~y </code></entry><entry><code>EXPR        </code></entry><entry>messages which contain EXPR in the `X-Label' field</entry></row>
            <row><entry><code>~z </code></entry><entry><code>[MIN]-[MAX] </code></entry><entry>messages with a size in the range MIN to MAX *)</entry></row>
            <row><entry><code>~= </code></entry><entry><code></code></entry><entry>duplicated messages (see $duplicate_threads)</entry></row>
            <row><entry><code>~$ </code></entry><entry><code></code></entry><entry>unreferenced messages (requires threaded view)</entry></row>
            <row><entry><code>~* </code></entry><entry><code></code></entry><entry>``From'' contains realname and (syntactically) valid address (excluded are addresses matching against alternates or any alias)</entry></row>
          </tbody>
        </tgroup>
      </table>
      </para>
      
      <para>
        Where EXPR are 
        <link linkend="regexp">regexp</link>.  Special attention has to be
        made when using regular expressions inside of patterns.  Specifically,
        Mutt-ng's parser for these patterns will strip one level of backslash
        (\),
        which is normally used for quoting.  If it is your intention to use a
        backslash in the regular expression, you will need to use two
        backslashes
        instead (\\).
      </para>
      
      <para>
        *) The forms <literal>&lt;&lsqb;MAX&rsqb;</literal>, <literal>
          &gt;&lsqb;MIN&rsqb;
        </literal>
        ,
        <literal>&lsqb;MIN&rsqb;-</literal> and <literal>-&lsqb;MAX&rsqb;</literal>
        are allowed, too.
      </para>
      
      <para>
        
      </para>
      
    </sect1>
    
    <sect1 id="commands">
      <title>Configuration Commands  </title>
      
      <para>
        The following are the commands understood by mutt.
      </para>
      
      <para>
        
        <itemizedlist>
          <listitem>
            
            <para>
              <literal>
                <link linkend="account-hook">account-hook</link>
              </literal>
              <emphasis>pattern</emphasis> <emphasis>command</emphasis>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="alias">alias</link>
              </literal>
              <emphasis>key</emphasis> <emphasis>address</emphasis> &lsqb; , <emphasis>
                address
              </emphasis>
              ,... &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="alias">alias</link>
              </literal>
              &lsqb; * &verbar; <emphasis>key</emphasis> ... &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="alternates">alternates</link>
              </literal>
              <emphasis>regexp</emphasis> &lsqb; <emphasis>regexp</emphasis>
              ... &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="alternates">alternates</link>
              </literal>
              &lsqb; * &verbar; <emphasis>regexp</emphasis> ... &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="alternative-order">alternative-order</link>
              </literal>
              <emphasis>mimetype</emphasis> &lsqb; <emphasis>mimetype</emphasis> ... &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="alternative-order">alternative-order</link>
              </literal>
              <emphasis>mimetype</emphasis> &lsqb; <emphasis>mimetype</emphasis> ... &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="append-hook">append-hook</link>
              </literal>
              <emphasis>regexp</emphasis> <emphasis>command</emphasis>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="auto-view">auto-view</link>
              </literal>
              <emphasis>mimetype</emphasis> &lsqb; <emphasis>mimetype</emphasis> ... &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="auto-view">auto-view</link>
              </literal>
              <emphasis>mimetype</emphasis> &lsqb; <emphasis>mimetype</emphasis> ... &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="bind">bind</link>
              </literal>
              <emphasis>map</emphasis> <emphasis>key</emphasis> <emphasis>
                function
              </emphasis>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="charset-hook">charset-hook</link>
              </literal>
              <emphasis>alias</emphasis> <emphasis>charset</emphasis>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="close-hook">close-hook</link>
              </literal>
              <emphasis>regexp</emphasis> <emphasis>command</emphasis>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="color">color</link>
              </literal>
              <emphasis>object</emphasis> <emphasis>foreground</emphasis> <emphasis>
                background
              </emphasis>
              &lsqb; <emphasis>regexp</emphasis> &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="color">color</link>
              </literal>
              <emphasis>index</emphasis> <emphasis>pattern</emphasis> &lsqb; <emphasis>
                pattern
              </emphasis>
              ... &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="exec">exec</link>
              </literal>
              <emphasis>function</emphasis> &lsqb; <emphasis>function</emphasis> ... &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="fcc-hook">fcc-hook</link>
              </literal>
              <emphasis>pattern</emphasis> <emphasis>mailbox</emphasis>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="fcc-save-hook">fcc-save-hook</link>
              </literal>
              <emphasis>pattern</emphasis> <emphasis>mailbox</emphasis>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="folder-hook">folder-hook</link>
              </literal>
              <emphasis>pattern</emphasis> <emphasis>command</emphasis>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="hdr-order">hdr-order</link>
              </literal>
              <emphasis>header</emphasis> &lsqb; <emphasis>header</emphasis>
              ... &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="hdr-order">hdr-order</link>
              </literal>
              <emphasis>header</emphasis> &lsqb; <emphasis>header</emphasis>
              ... &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="charset-hook">charset-hook</link>
              </literal>
              <emphasis>charset</emphasis> <emphasis>local-charset</emphasis>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="ignore">ignore</link>
              </literal>
              <emphasis>pattern</emphasis> &lsqb; <emphasis>pattern</emphasis>
              ... &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="ignore">ignore</link>
              </literal>
              <emphasis>pattern</emphasis> &lsqb; <emphasis>pattern</emphasis>
              ... &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="lists">lists</link>
              </literal>
              <emphasis>regexp</emphasis> &lsqb; <emphasis>regexp</emphasis>
              ... &rsqb; 
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="lists">lists</link>
              </literal>
              <emphasis>regexp</emphasis> &lsqb; <emphasis>regexp</emphasis>
              ... &rsqb; 
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="macro">macro</link>
              </literal>
              <emphasis>menu</emphasis> <emphasis>key</emphasis> <emphasis>
                sequence
              </emphasis>
              &lsqb; <emphasis>description</emphasis> &rsqb; 
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="mailboxes">mailboxes</link>
              </literal>
              <emphasis>filename</emphasis> &lsqb; <emphasis>filename</emphasis> ... &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="mbox-hook">mbox-hook</link>
              </literal>
              <emphasis>pattern</emphasis> <emphasis>mailbox</emphasis>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="message-hook">message-hook</link>
              </literal>
              <emphasis>pattern</emphasis> <emphasis>command</emphasis>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="mime-lookup">mime-lookup</link>
              </literal>
              <emphasis>mimetype</emphasis> &lsqb; <emphasis>mimetype</emphasis> ... &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="mime-lookup">mime-lookup</link>
              </literal>
              <emphasis>mimetype</emphasis> &lsqb; <emphasis>mimetype</emphasis> ... &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="color">color</link>
              </literal>
              <emphasis>object attribute</emphasis> &lsqb; <emphasis>regexp</emphasis> &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="color">color</link>
              </literal>
              <emphasis>index</emphasis> <emphasis>pattern</emphasis> &lsqb; <emphasis>
                pattern
              </emphasis>
              ... &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="my-hdr">my-hdr</link>
              </literal>
              <emphasis>string</emphasis>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="my-hdr">my-hdr</link>
              </literal>
              <emphasis>field</emphasis> &lsqb; <emphasis>field</emphasis> ...
              &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="open-hook">open-hook</link>
              </literal>
              <emphasis>regexp</emphasis> <emphasis>command</emphasis>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="crypt-hook">crypt-hook</link>
              </literal>
              <emphasis>pattern</emphasis> <emphasis>key-id</emphasis>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="push">push</link>
              </literal>
              <emphasis>string</emphasis>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="set">set</link>
              </literal>
              <emphasis>variable</emphasis> &lsqb;<emphasis>variable</emphasis>
              ... &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="save-hook">save-hook</link>
              </literal>
              <emphasis>regexp</emphasis> <emphasis>filename</emphasis>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="score-command">score-command</link>
              </literal>
              <emphasis>pattern</emphasis> <emphasis>value</emphasis>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="score-command">score-command</link>
              </literal>
              <emphasis>pattern</emphasis> &lsqb; <emphasis>pattern</emphasis>
              ... &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="send-hook">send-hook</link>
              </literal>
              <emphasis>regexp</emphasis> <emphasis>command</emphasis>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="reply-hook">reply-hook</link>
              </literal>
              <emphasis>regexp</emphasis> <emphasis>command</emphasis>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="set">set</link>
              </literal>
              &lsqb;no&verbar;inv&rsqb;<emphasis>variable</emphasis>&lsqb;=<emphasis>
                value
              </emphasis>
              &rsqb; &lsqb; <emphasis>variable</emphasis> ... &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="set">set</link>
              </literal>
              <emphasis>variable</emphasis> &lsqb;<emphasis>variable</emphasis>
              ... &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="source">source</link>
              </literal>
              <emphasis>filename</emphasis>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="spam">spam</link>
              </literal>
              <emphasis>pattern</emphasis> <emphasis>format</emphasis>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="spam">spam</link>
              </literal>
              <emphasis>pattern</emphasis>
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="lists">lists</link>
              </literal>
              <emphasis>regexp</emphasis> &lsqb; <emphasis>regexp</emphasis>
              ... &rsqb; 
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="lists">lists</link>
              </literal>
              <emphasis>regexp</emphasis> &lsqb; <emphasis>regexp</emphasis>
              ... &rsqb; 
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="set">set</link>
              </literal>
              <emphasis>variable</emphasis> &lsqb;<emphasis>variable</emphasis>
              ... &rsqb;
            </para>
          </listitem>
          <listitem>
            
            <para>
              <literal>
                <link linkend="unhook">unhook</link>
              </literal>
              <emphasis>hook-type</emphasis>
            </para>
          </listitem>
          
        </itemizedlist>
        
      </para>
      
    </sect1>
    
    <sect1 id="variables">
      <title>Configuration variables</title>
      
      <para>
        The following list contains all variables which, in the process of
        providing more consistency, have been renamed and are partially even
        removed already. The left column contains the old synonym variables,
        the right column the full/new name:
      </para>
      
      <para>
        <anchor id="sect-obsolete"/>

        <table>
          <title>Obsolete Variables</title>
          <tgroup cols="2" align="left" colsep="1" rowsep="1">
          <thead>
            <row>
              <entry>Old Name</entry>
              <entry>New Name</entry>
            </row>
          </thead>
          <tbody>
            <row><entry><code>edit_hdrs</code></entry><entry><code>edit_headers</code></entry></row>
            <row><entry><code>forw_decode</code></entry><entry><code>forward_decode</code></entry></row>
            <row><entry><code>forw_format</code></entry><entry><code>forward_format</code></entry></row>
            <row><entry><code>forw_quote</code></entry><entry><code>forward_quote</code></entry></row>
            <row><entry><code>hdr_format</code></entry><entry><code>index_format</code></entry></row>
            <row><entry><code>indent_str</code></entry><entry><code>indent_string</code></entry></row>
            <row><entry><code>mime_fwd</code></entry><entry><code>mime_forward</code></entry></row>
            <row><entry><code>msg_format</code></entry><entry><code>message_format</code></entry></row>
            <row><entry><code>pgp_autosign</code></entry><entry><code>crypt_autosign</code></entry></row>
            <row><entry><code>pgp_autoencrypt</code></entry><entry><code>crypt_autoencrypt</code></entry></row>
            <row><entry><code>pgp_replyencrypt</code></entry><entry><code>crypt_replyencrypt</code></entry></row>
            <row><entry><code>pgp_replysign</code></entry><entry><code>crypt_replysign</code></entry></row>
            <row><entry><code>pgp_replysignencrypted</code></entry><entry><code>crypt_replysignencrypted</code></entry></row>
            <row><entry><code>pgp_verify_sig</code></entry><entry><code>crypt_verify_sig</code></entry></row>
            <row><entry><code>pgp_create_traditional</code></entry><entry><code>pgp_autoinline</code></entry></row>
            <row><entry><code>pgp_auto_traditional</code></entry><entry><code>pgp_replyinline</code></entry></row>
            <row><entry><code>forw_decrypt</code></entry><entry><code>forward_decrypt</code></entry></row>
            <row><entry><code>smime_sign_as</code></entry><entry><code>smime_default_key</code></entry></row>
            <row><entry><code>post_indent_str</code></entry><entry><code>post_indent_string</code></entry></row>
            <row><entry><code>print_cmd</code></entry><entry><code>print_command</code></entry></row>
            <row><entry><code>shorten_hierarchy</code></entry><entry><code>sidebar_shorten_hierarchy</code></entry></row>
            <row><entry><code>ask_followup_to</code></entry><entry><code>nntp_ask_followup_to</code></entry></row>
            <row><entry><code>ask_x_comment_to</code></entry><entry><code>nntp_ask_x_comment_to</code></entry></row>
            <row><entry><code>catchup_newsgroup</code></entry><entry><code>nntp_catchup</code></entry></row>
            <row><entry><code>followup_to_poster</code></entry><entry><code>nntp_followup_to_poster</code></entry></row>
            <row><entry><code>group_index_format</code></entry><entry><code>nntp_group_index_format</code></entry></row>
            <row><entry><code>inews</code></entry><entry><code>nntp_inews</code></entry></row>
            <row><entry><code>mime_subject</code></entry><entry><code>nntp_mime_subject</code></entry></row>
            <row><entry><code>news_cache_dir</code></entry><entry><code>nntp_cache_dir</code></entry></row>
            <row><entry><code>news_server</code></entry><entry><code>nntp_host</code></entry></row>
            <row><entry><code>newsrc</code></entry><entry><code>nntp_newsrc</code></entry></row>
            <row><entry><code>nntp_poll</code></entry><entry><code>nntp_mail_check</code></entry></row>
            <row><entry><code>pop_checkinterval</code></entry><entry><code>pop_mail_check</code></entry></row>
            <row><entry><code>post_moderated</code></entry><entry><code>nntp_post_moderated</code></entry></row>
            <row><entry><code>save_unsubscribed</code></entry><entry><code>nntp_save_unsubscribed</code></entry></row>
            <row><entry><code>show_new_news</code></entry><entry><code>nntp_show_new_news</code></entry></row>
            <row><entry><code>show_only_unread</code></entry><entry><code>nntp_show_only_unread</code></entry></row>
            <row><entry><code>x_comment_to</code></entry><entry><code>nntp_x_comment_to</code></entry></row>
            <row><entry><code>smtp_auth_username</code></entry><entry><code>smtp_user</code></entry></row>
            <row><entry><code>smtp_auth_password</code></entry><entry><code>smtp_pass</code></entry></row>
            <row><entry><code>user_agent</code></entry><entry><code>agent_string</code></entry></row>
          </tbody>
        </tgroup>
      </table>

      </para>
      
      <para>
        The <literal>contrib</literal> subdirectory contains a script named
        <literal>update-config.pl</literal> which eases migration.
      </para>
      
      <para>
        A complete list of current variables follows.
      </para>