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<!DOCTYPE BOOK PUBLIC "-//FreeBSD//DTD DocBook V4.1-Based Extension//EN" [
<!ENTITY RCL "<application>Recoll</application>">
<!ENTITY XAP "<application>Xapian</application>">

]>
 
<book lang="en">
  
  <bookinfo>
    <title>Recoll user manual</title>


    <author>
      <firstname>Jean-Francois</firstname>
      <surname>Dockes</surname>
      <affiliation>
        <address><email>jean-francois.dockes@wanadoo.fr</email></address>
      </affiliation>
    </author>

    <copyright>
      <year>2005</year>
      <holder role="mailto:jean-francois.dockes@wanadoo.fr">Jean-Francois
      Dockes</holder>
    </copyright>

    <releaseinfo>$Id: usermanual.sgml,v 1.36 2007-01-25 15:47:45 dockes Exp $</releaseinfo>

    <abstract>
      <para>This document introduces full text search notions
      and describes the installation and use of the &RCL; application.</para>
    </abstract>


  </bookinfo>
  
  <chapter id="rcl.introduction">
    <title>Introduction</title>

    <sect1 id="rcl.introduction.tryit">
      <title>Giving it a try</title>

      <para>If you do not like reading manuals (who does?) and would
      like to give &RCL; a try, just perform <link
      linkend="rcl.install.binary">installation</link> and start the
      <command>recoll</command> user interface, which will index your
      home directory by default, allowing you to search immediately after
      indexing completes.</para>

      <para>Do not do this if your home directory contains a huge
      number of documents and you do not want to wait or are very
      short on disk space. In this case, you may want to edit the <link
      linkend="rcl.indexing.config">configuration file</link> first to
      restrict the indexed area.</para>

      <para>Also be aware that you may need to install the
      appropriate <link linkend="rcl.install.external">
      supporting applications</link> for document types that need
      them (for example <application>antiword</application> for
      ms-word files).</para>
      
    <sect1 id="rcl.introduction.search"> 
      <title>Full text search</title>

      <para>&RCL; is a full text search application. Full text search
        applications let you find your data by content rather
        than by external attributes (like a file name). More
        specifically, they will let you specify words (terms) that
        should or should not appear in the text you are looking for,
        and return a list of matching documents, ordered so that the
        most <emphasis>relevant</emphasis> documents will appear
        first.</para>

      <para>You do not need to remember in what file or email message you
        stored a given piece of information. You just ask for related
        terms, and the tool will return a list of documents where
        those terms are prominent, in a similar way to Internet search
        engines.</para>

      <para>&RCL; tries to determine which documents are most relevant to
      the search terms you provide. Computer algorithms for determining
      relevance can be very complex, and in general are inferior to the
      power of the human mind to rapidly determine relevance. The quality
      of relevance guessing by the search tool is probably the most
      important element for a search application.</para>

      <para>In many cases, you are looking for all the forms of a
        word, not for a specific form or spelling. These different
        forms may include plurals, different tenses for a verb, or
        terms derived from the same root or <emphasis>stem</emphasis>
        (example: floor, floors, floored, flooring...). &RCL; will by
        default expand queries to all such related terms (words that
        reduce to the same stem). This expansion can be disabled at
        search time.</para>

     <para>Stemming, by itself, does not accommodate for misspellings or
        phonetic searches. &RCL; supports these features through a specific
        tool (the <literal>term explorer</literal>) which will let you
        explore the set of index terms along different modes.</para> 


    </sect1>

      <sect1 id="rcl.introduction.recoll">
      <title>Recoll overview</title>

      <para>&RCL; uses the 
      <ulink url="http://www.xapian.org">&XAP;</ulink> information retrieval
      library as its storage and retrieval engine. &XAP; is a very
      mature package using <ulink
      url="http://www.xapian.org/docs/intro_ir.html">a sophisticated
      probabilistic ranking model</ulink>. &RCL; provides the interface
      to get data into (indexing) and out (searching) of the system.</para>

      <para>In practice, &XAP; works by remembering where terms appear
      in your document files. The acquisition process is called
      indexing. </para> 

      <para>The resulting index can be big (roughly the size of the
        original document set), but it is not a document
        archive. &RCL; can only display documents that still exist at
        the place from which they were indexed. (Actually, there is a
        way to reconstruct a document from the information in the
        index, but the result is not nice, as all formatting,
        punctuation and capitalization are lost).</para>

      <para>&RCL; stores all internal data in <application>Unicode
      UTF-8</application> format, and it can index files with
      different character sets, encodings, and languages into the same
      index. It has input filters for many document types.</para>
      
      <para>Stemming depends on the document language. &RCL; stores
      the unstemmed versions of terms and uses auxiliary databases for
      term expansion. It can switch stemming languages, or add a
      language, without re-indexing.  Storing documents in different
      languages in the same index is possible, and useful in
      practice, but does introduce possibilities of confusion. &RCL;
      currently makes no attempt at automatic language recognition.</para>

      <para>&RCL; has many parameters which define exactly what to
        index, and how to classify and decode the source
        documents. These are kept in a <link
        linkend="rcl.indexing.config">configuration file</link>. A
        default configuration is copied into a standard location
        (usually something like
        <filename>/usr/[local/]share/recoll/examples</filename>)
        during installation. The default parameters from this file may
        be overridden by values that you set inside your personal
        configuration, found by default in the
        <filename>.recoll</filename> sub-directory of your home
        directory. The default configuration will index your home
        directory with default parameters and should be sufficient for
        giving &RCL; a try, but you may want to adjust it
        later.</para>

      <para><link linkend="rcl.indexing.periodic.exec">Indexing</link>
      is started automatically the first time you execute the
      <command>recoll</command> search graphical user interface, or by
      executing the <command>recollindex</command> command.</para>

      <para><link linkend="rcl.search">Searches</link> are
      performed inside the <command>recoll</command> 
      program, which has many options to help you find what you are
      looking for.</para> 

    </sect1>
  </chapter>


  <chapter id="rcl.indexing">
    <title>Indexing</title>

    <sect1 id="rcl.indexing.introduction">
      <title>Introduction</title>

      <para>Indexing is the process by which the set of documents is
      analyzed and the data entered into the database. &RCL; indexing
      is normally incremental: documents will only be processed if
      they have been modified. On the first execution, of course, all
      documents will need processing. A full index build can be forced
      later by specifying an option to the indexing command
      (<command>recollindex -z</command>).</para> 

      <para>&RCL; indexing can be performed with two different
       methods:</para>

      <itemizedlist>

	<listitem>
	  <formalpara><title>Periodic indexing:</title>
	    <para>indexing takes place at discrete
	times, by executing the <command>recollindex</command>
	command. The typical usage is to have a nightly indexing run 
      <link linkend="rcl.indexing.periodic.automat">programmed</link> into your
      <command>cron</command> file.</para>
	  </formalpara>
	</listitem>

	<listitem>
	  <formalpara><title>Real time indexing:</title>
	    <para>indexing takes place as soon as a file is created or
	    changed. <command>recollindex</command> runs as a daemon
	    and uses a file system alteration monitor such as
	    <application>Fam</application>, 
	    <application>Gamin</application> or
	    <application>inotify</application> do detect file changes.
            Monitoring a big directory tree can consume significant
            system resources.</para>
	  </formalpara>
	</listitem>
      </itemizedlist>

      <para>The choice between the two methods is mostly a matter of
      preference, and they can be combined by setting up multiple
      indexes (ie: use periodic indexing on a big documentation
      directory, and real time indexing on a small home
      directory). Monitoring a big file system tree can consume
      significant system resources, for dubious gains. <para>

      <para>&RCL; knows about quite a few different document
      types. The parameters for document types recognition and
      processing are set in 
       <link linkend="rcl.indexing.config">configuration files</link>
      Most file types, like HTML or word processing files, only hold
      one document. Some file types, like mail folder files can hold
      many individually indexed documents.
      </para>

      <para>&RCL; indexing processes plain text, HTML, openoffice
      and e-mail files internally. Other types (ie: postscript, pdf,
      ms-word, rtf) need external applications for preprocessing. The
      list is in the <link linkend="rcl.install.external">
      installation</link> section.</para>

      <para>Without further configuration, &RCL; will index all
      appropriate files from your home directory, with a reasonable
      set of defaults.</para>

      <para>In some cases, it may be interesting to index different
      areas of the file system to separate databases. You can do this
      by using multiple configuration directories, each indexing a
      file system area to a specific database. See the <link
      linkend="rcl.search.multidb">section about using multiple
      databases</link> for more information on multiple configurations
      and indexes. </para>
    </sect1>

    <sect1 id="rcl.indexing.storage">
      <title>Index storage</title>

      <para>The default location for the index data is the
      <filename>xapiandb</filename> subdirectory of the &RCL;
      configuration directory, typically
      <filename>$HOME/.recoll/xapiandb/</filename>. This can be
      changed via two different methods (with different purposes):</para>

      <itemizedlist>

	  <listitem><para>You can specify a different configuration
	  directory by setting the <literal>RECOLL_CONFDIR</literal>
          environment variable, or using the <literal>-c</literal>
          option to the &RCL; commands. This method would typically be
          used to index different areas of the file system to
          different indexes. For example, if you were to issue the
          following commands: 
          <programlisting>
export RECOLL_CONFDIR=~/.indexes-email
recoll
          </programlisting> Then &RCL; would use configuration files
          stored in <filename>~/.indexes-email/</filename> and,
          (unless specified otherwise in
          <filename>recoll.conf</filename>) would look for 
          the index in <filename>~/.indexes-email/xapiandb/</filename>.

          <para>Using multiple configuration directories and 
          <link linkend="rcl.install.config.recollconf">configuration
          options</link> allows you to tailor multiple configurations
          and indexes to handle whatever subset of the available data
          that you wish to make searchable.</para>

	  </listitem>
	  <listitem><para>You can also specify a different storage
	  location for the index by setting the <literal>dbdir</literal>
	  parameter in the configuration file 
          (see the <link linkend="rcl.install.config.recollconf">configuration
          section</link>). This method would mainly be of use if you
          wanted to keep the configuration directory in its default location,
          but desired another location for the index, typically out of
          disk occupation concerns.</para>
	  </listitem>

	</itemizedlist>

      <para>The size of the index is determined by the size of the set
      of documents, but the ratio can vary a lot. For a typical mixed
      set of documents, the index size will often be close to
      the data set size. In specific cases (a set of compressed
      mbox files for example), the index can become much bigger than
      the documents. It may also be much smaller if the documents
      contain a lot of images or other non-indexed data (an extreme
      example being a set of mp3 files where only the tags would be
      indexed).</para>

      <para>Of course, images, sound and video do not increase the
      index size, which means that it will be quite typical nowadays
      (2006), that even a big index will be negligible against the
      total amount of data on the computer.</para>
      
      <para>The index data directory (<filename>xapiandb</filename>)
      only contains data that can be completely rebuilt by an index
      run, and it can always be destroyed safely.</para>

      <sect2 id="rcl.indexing.storage.security">
	<title>Security aspects</title>

	<para>The &RCL; index does not hold copies of the indexed
	documents. But it does hold enough data to allow for an almost
	complete reconstruction. If confidential data is indexed,
	access to the database directory should be restricted. </para>

	<para>As of version 1.4, &RCL; will create the configuration
	directory with a mode of 0700 (access by owner only). As the
	index data directory is by default a sub-directory of the
	configuration directory, this should result in appropriate
	protection.</para> 

	<para>If you use another setup, you should think of the kind
	of protection you need for your index, and set the directory
	and files access modes appropriately.</para>

      </sect2>

    </sect1>

    <sect1 id="rcl.indexing.config">
      <title>The indexing configuration</title>

      <para>You can control which areas of the file system are
      indexed, and how files are processed, by setting variables inside
      the <link linkend="rcl.install.config">&RCL; configuration
      files</link>.</para>

      <para>You can also use <link linkend="rcl.search.multidb">multiple 
      indexes</link> defined by separate configurations, typically to 
      separate personal and shared indexes, or to take advantage of
      the organization of your data to improve search precision.</para> 

      <para>The first time you start <command>recoll</command>, you
      will be asked whether or not you would like recoll to build the
      index. If you want to adjust the configuration before indexing,
      just click <guilabel>Cancel</guilabel> at this point. That way,
      recoll will have created a ~/.recoll directory containing empty
      configuration files.</para>

      <para>The configuration is documented inside the <link
      linkend="rcl.install.config">installation chapter</link> of
      this document, or in the recoll.conf(5) man page. The most
      immediately useful variable you may interested in is probably <link
      linkend="rcl.install.config.recollconf.topdirs">topdirs</link>,
      which determines what subtrees get indexed.</para>

      <para>The applications needed to index file types other than
      text, HTML or email (ie: pdf, postscript, ms-word...) are
      described in the <link linkend="rcl.install.external">external
      packages section</link></para>

    </sect1>

    <sect1 id="rcl.indexing.periodic">
      <title>Periodic indexing</title>

      <sect2 id="rcl.indexing.periodic.exec">
	<title>Starting indexing</title>

	<para>Indexing is performed either by the
        <command>recollindex</command> program, or by the
        indexing thread inside the <command>recoll</command>
        program (use the <guimenu>File</guimenu> menu). Both programs
        will use of the <literal>RECOLL_CONFDIR</literal>
        variable or accept a <literal>-c</literal>
        <replaceable>confdir</replaceable> option to specify the
        configuration directory to be used.</para>

	<para>If the <command>recoll</command> program finds no index
       when it starts, it will automatically start indexing (except
       if canceled).</para>

	<para>It is best to avoid interrupting the indexing process, as
        this may sometimes leave the index in a bad state.  This is
        not a serious problem, as you then just need to delete 
        the index files and restart the indexing. The index files are
        normally stored in the <filename>$HOME/.recoll/xapiandb</filename>
        directory, which you can just delete if needed. Alternatively,
        you can start <command>recollindex</command> with option
        <literal>-z</literal>, which will reset the database before
        indexing.</para> 

      </sect2>

      <sect2 id="rcl.indexing.periodic.automat">
	<title>Using <command>cron</command> to automate
      indexing</title>

	<para>The most common way to set up indexing is to have a cron
      task execute it every night. For example the following
      <filename>crontab</filename> entry would do it every day at
      3:30AM (supposing <command>recollindex</command> is in your PATH):</para>

	<programlisting>30 3 * * * recollindex > /tmp/recolltrace 2>&1</programlisting>

	<para>The usual command to edit your
      <filename>crontab</filename> is 
        <userinput>crontab -e</userinput> (which will usually start the
      <command>vi</command> editor to edit the file). You may have
      more sophisticated tools available on your system.</para>

      </sect2>
    </sect1>

    <sect1 id="rcl.indexing.monitor">
      <title>Real time indexing</title>

      <para>Real time monitoring/indexing is performed by starting the
      <command>recollindex -m</command> command. With this option,
      <command>recollindex</command> will detach from the terminal and
      become a daemon, permanently monitoring file changes and updating
      the index.</para>

      <para>The real time indexing support can be customised during package 
       <link linkend="rcl.install.building.build">configuration</link>
      with the <literal>--with[out]-fam</literal> or
      <literal>--with[out]-inotify</literal> options.  The default is
      currently to include inotify monitoring on systems that support
      it.</para>

      <para>The <filename>rclmon.sh</filename> script can be used to
      easily start and stop the daemon. It can be found in the
      <filename>examples</filename> directory (typically
      <filename>/usr/local/[share/]recoll/examples</filename>).</para>

      <para>Starting the daemon is normally performed as part
      of the user session script. For example, my out of fashion
      xdm-based session has a <filename>.xsession</filename> script
      with the following lines at the end:</para>

      <programlisting>recollconf=$HOME/.recoll-home
recolldata=/usr/local/share/recoll
RECOLL_CONFDIR=$recollconf $recolldata/examples/rclmon.sh start

fvwm 

</programlisting>

      <para>The indexing daemon gets started, then the window manager,
      for which the session waits.</para> <para>By default the
      indexing daemon will monitor the state of the X11 session, and
      exit when it finishes, it is not necessary to kill it
      explicitely. (The X11 server monitoring can be disabled with option
      <literal>-x</literal> to <command>recollindex</command>).
      </para>

      <para>Under KDE, you can place a small script to start
      <command>recollindex -m</command> under
      <filename>$HOME/.kde/Autostart</filename>. This will be executed
      when the session begins.</para>
      
      <para>There is a similar mechanism under Gnome (find the session
      control tool in the menus and use the "Startup programs" tab).</para>

      <para>By default, the indexing daemon will write its messages to
      a file inside the configuration directory (this is controlled by
      the <literal>daemlogfilename</literal> and
      <literal>daemloglevel</literal> configuration parameters). You
      may want to change this. Also the log file will only be truncated
      when the daemon starts. If the daemon runs permanently, the log
      file may grow quite big, depending on the log level.</para>

      <para>While it is convenient that data is indexed in real time,
      repeated indexing can generate a significant load on the system
      when files such as email folders change. You probably do not
      want to enable it if your system is short on resources. Periodic
      indexing is adequate in most cases.</para>

    </sect1>

  </chapter>

  <chapter id="rcl.search">
    <title>Searching</title>

    <para>The <command>recoll</command> program provides the user
    interface for searching. It is based on the
    <application>QT</application> library.</para>

    <sect1 id="rcl.search.simple">
      <title>Simple search</title>

      <procedure>
	<step><para>Start the <command>recoll</command> program.</para>
	</step>
	<step><para>Possibly choose a search mode: <guilabel>Any
	term</guilabel> or <guilabel>All terms</guilabel> or
	<guilabel>File name</guilabel>.</para>
	</step>
	<step><para>Enter search term(s) in the text field at the top of the
        window.</para>
	</step>
	<step><para>Click the <guilabel>Search</guilabel> button or
        hit the <keycap>Enter</keycap> key to start the search.</para>
	</step>
      </procedure>

      <para>The initial default search mode is <guilabel>All
        terms</guilabel>. This will look for documents containing all
        of the search terms (the ones with more terms will get better
        scores). <guilabel>Any term</guilabel> will search for
        documents where at least one of the terms appear. <guilabel>File
        name</guilabel> will specifically look for file names.</para>

      <para>The fourth entry (<guilabel>Query Language</guilabel>) is
      described in <link linkend="rcl.search.lang">its own
      section</link>.</para> 

      <para>All search modes allow wildcards inside terms
        (<literal>*</literal>, <literal>?</literal>,
        <literal>[]</literal>). You may want to have a look at the
        <link linkend="rcl.search.wildcards">section about wildcards</link>
        for more information about this.</para>

      <para>You can search for exact phrases (adjacent words in a
      given order) by enclosing the input inside double quotes. Ex:
     <literal>"virtual reality"</literal>.</para>

      <para>Character case has no influence on search, except that you
      can disable stem expansion for any term by capitalizing it. Ie:
      a search for <literal>floor</literal> will also normally look for 
      <literal>flooring</literal>, <literal>floored</literal>, etc., but
      a search for <literal>Floor</literal> will only look for
      <literal>floor</literal>, in any character case (stemming can
      also be disabled globally in the preferences). </para>

      <para>&RCL; remembers the last few searches that you
        performed. You can use the simple search text entry widget (a
        combobox) to recall them (click on the thing at the right of the
        text field). Please note, however, that only the search texts
        are remembered, not the mode (all/any/file name).</para>

      <para>Typing <keycap>Esc</keycap> <keycap>Space</keycap> while
        entering a word in the simple search entry will open a window
        with possible completions for the word. The completions are
        extracted from the database.</para>

      <para>Double-clicking on a word in the result list or a preview
      window will insert it into the simple search entry field.</para>

      <para>You can use the <guilabel>Tools</guilabel> / <guilabel>Advanced
        search</guilabel> dialog for more complex searches.</para>
    </sect1>

    <sect1 id="rcl.search.reslist">
      <title>The result list</title>

      <para>After starting a search, a list of results will instantly
       be displayed in the main list window.</para> 

      <para>By default, the document list is presented in order of
       relevance (how well the system estimates that the document
       matches the query). You can specify a different ordering by
       using the  <link linkend="rcl.search.sort"><guilabel>Tools</guilabel>
        / <guilabel>Sort parameters</guilabel></link> dialog.</para>

      <para>Clicking on the
       <literal>Preview</literal> link for an entry will open an
       internal preview window for the document. Further
       <literal>Preview</literal> clicks for the same search will open
       tabs in the existing preview window. You can use
       <keycap>Shift</keycap>+Click to force the creation of another
       preview window, which may be useful to view the documents side
       by side. (You can also browse successive results in a single
       preview window by typing
       <keycap>Shift</keycap>+<keycap>ArrowUp/Down</keycap> in the
       window).</para> 

      <para>Clicking the <literal>Edit</literal> link will attempt to 
       start an external viewer. The viewers can be configured through the
       user preferences dialog, or by editing the
       <filename>mimeview</filename> configuration file.</para>

      <para>The <literal>Preview</literal> and <literal>Edit</literal>
       edit links may not be present for all entries, meaning that
       &RCL; has no configured way to preview a given file type (which
       was indexed by name only), or no configured external viewer for
       the file type. This can sometimes be adjusted simply by tweaking
       the <link linkend="rclinstall.config.mimemap">
             <filename>mimemap</filename></link> and  
       <link linkend="rclinstall.config.mimeview">
       <filename>mimeview</filename></link> configuration files (the latter
       can be modified with the user preferences dialog).</para> 

      <para>You can click on the <literal>Query details</literal> link
        at the top of the results page to see the query actually 
        performed, after stem expansion and other processing.</para>

      <para>Double-clicking on any word inside the result list or a
      preview window will insert it into the simple search text.</para>

      <para>The result list is divided into pages (the size of which
       you can change in the preferences). Use the arrow buttons in the
       toolbar or the links at the bottom of the page to browse the
       results.</para>


      <sect2 id="rcl.search.resultlist.menu">
	<title>The result list right-click menu</title>

	<para>Apart from the preview and edit links, you can display a
          pop-up menu by right-clicking over a paragraph in the result
         list. This menu has the following entries:</para>

	<itemizedlist>
	  <listitem><para><guilabel>Preview</guilabel></para></listitem>
	  <listitem><para><guilabel>Edit</guilabel></para></listitem>
	  <listitem><para><guilabel>Copy File Name</guilabel></para></listitem>
	  <listitem><para><guilabel>Copy Url</guilabel></para></listitem>
	  <listitem><para><guilabel>Find similar</guilabel></para></listitem>
	  <listitem><para><guilabel>Find similar</guilabel></para></listitem>
	  <listitem><para><guilabel>Parent document</guilabel></para></listitem>
	</itemizedlist>

	<para>The <guilabel>Preview</guilabel> and
          <guilabel>Edit</guilabel> entries do the same thing as the 
          corresponding links.</para>

	<para>The <guilabel>Copy File Name</guilabel> and
	<guilabel>Copy Url</guilabel> copy the relevant data to the
	clipboard, for later pasting.</para> 

        <para>The <guilabel>Find similar</guilabel> entry will select
          a number of relevant term from the current document and enter
          them into the simple search field. You can then start a simple
          search, with a good chance of finding documents related to the
         current result.</para>

        <para>The <guilabel>Parent document</guilabel> entry will
          appear for documents which are not actually files but are
          part of, or attached to, a higher level document. This entry
          is mainly useful for email attachments and permits viewing
          the message to which the document is attached. Note that the
          entry will also appear for an email which is part of an mbox
          folder file, but that you can't actually visualize the
          folder (there will be an error dialog if you try). &RCL; is
          unfortunately not yet smart enough to disable the entry in
          this case.</para>

      </sect2>
    </sect1>

    <sect1 id="rcl.search.preview">
      <title>The preview window</title>

      <para>The preview window opens when you first click a
      <literal>Preview</literal> link inside the result list.</para>

      <para>Subsequent preview requests for a given search open new
      tabs in the existing window (except if you hold the
      <keycap>Shift</keycap> key while clicking which will open a new
      window for side by side viewing).</para>
      
      <para>Starting another search and requesting a preview will
      create a new preview window. The old one stays open until you
      close it.</para>

      <para>You can close a preview tab by typing <keycap>^W</keycap> 
      (<keycap>Ctrl</keycap> + <keycap>W</keycap>) in the
      window. Closing the last tab for a window will also close the
      window.</para> 

      <para>Of course you can also close a preview window by using the
      window manager button in the top of the frame.</para>

      <para>You can display successive or previous documents from the
      result list inside a preview tab by typing
      <keycap>Shift</keycap>+<keycap>Down</keycap> or
      <keycap>Shift</keycap>+<keycap>Up</keycap> (<keycap>Down</keycap>
      and <keycap>Up</keycap> are the arrow keys).</para> 

      <para>The preview tabs have an internal incremental search
      function. You initiate the search either by typing a
      <keycap>/</keycap> (slash) inside the text area or by clicking
      into the <guilabel>Search for:</guilabel> text field and
      entering the search string. You can then use the
      <guilabel>Next</guilabel> and <guilabel>Previous</guilabel>
      buttons to find the next/previous occurrence. You can also type
      <keycap>F3</keycap> inside the text area to get to the next
      occurrence.</para>

      <para>If you have a search string entered and you use ^Up/^Down
      to browse the results, the search is initiated for each successive
      document. If the string is found, the cursor will be positioned
      at the first occurrence of the search string.</para>

    </sect1>

    <sect1 id="rcl.search.lang">
      <title>The query language</title>

      <para>The query language processor is activated on the
      simple search entry when the search mode selector is set to
      <guilabel>Query Language</guilabel>.</para>

      <para>Here follows a sample request that we are going to
      explain:</para>
      <programlisting>
          mime:message/rfc822 author:"john doe" Beatles OR Lennon Live OR Unplugged -potatoes
      </programlisting>

      <para>This would search for all email messages with 
      <replaceable>John Doe</replaceable>
      appearing as a phrase in the <literal>From:</literal> header,
      and containing either <replaceable>beatles</replaceable> or
      <replaceable>lennon</replaceable> and either
      <replaceable>live</replaceable> or
      <replaceable>unplugged</replaceable> but not
      <replaceable>potatoes</replaceable>.</para>

      <para>The first element, <literal>mime:message/rfc822</literal>
      is a special switch that restricts the results to be email
      messages. There could be several such switches, which would form
      a list of allowed types.</para>

      <para>The second element <literal>author:"john doe"</literal> is
      a phrase search limited to a specific field. Phrase searches are
      specified as usual by enclosing the words in double quotes. The
      field specification appears before the colon. &RCL; currently
      manages the following fields:</para>
      <itemizedlist>
	<listitem><para><literal>title</literal>,
	<literal>subject</literal> or <literal>caption</literal> are
	synonyms which specify data to be searched for in the
	document title or subject.</para>
	</listitem>
	<listitem><para><literal>author</literal> or
	<literal>from</literal> for searching the documents originators.</para>
	</listitem>
	<listitem><para><literal>keyword</literal> for searching the
	document specified keywords (few documents actually have any).</para>
	</listitem>
      </itemizedlist>

      <para>The query language is currently the only way to use the
      &RCL; field search capability.</para>

      <para>All elements in the search entry are normally combined
      with an implicit AND. It is possible to specify that elements be
      OR'ed instead, as in <replaceable>Beatles</replaceable>
      <literal>OR</literal> <replaceable>Lennon</replaceable>. The
      <literal>OR</literal> must be entered literally (capitals), and
      it has priority over the AND associations:
      <replaceable>word1</replaceable>
      <replaceable>word2</replaceable> <literal>OR</literal>
      <replaceable>word3</replaceable> 
      means 
      <replaceable>word1</replaceable> AND 
      (<replaceable>word2</replaceable> <literal>OR</literal>
      <replaceable>word3</replaceable>)
      not 
      (<replaceable>word1</replaceable> AND
      <replaceable>word2</replaceable>) <literal>OR</literal>
      <replaceable>word3</replaceable>. Do not enter explicit
      parenthesis, they are not supported for now.</para>

      <para>An entry preceded by a <literal>-</literal> specifies a
      term that should <emphasis>not</emphasis> appear.</para>

      <para>Words inside phrases and capitalized words are not
      stem-expanded. Wildcards may be used anywhere.</para>

      <para>You can use the <literal>show query</literal> link at the
      top of the result list to check the exact query which was
      finally executed by Xapian.</para>

    </sect1>

    <sect1 id="rcl.search.complex">
      <title>Complex/advanced search</title>

      <para>The advanced search dialog has a number of fields that
        will allow a more refined search. Each entry field is
        configurable for the following modes:</para>

        <itemizedlist>
	  <listitem><para>All terms.</para>
	  </listitem>
	  <listitem><para>Any term.</para>
	  </listitem>
	  <listitem><para>None of the terms.</para>
	  </listitem>
	  <listitem><para>Phrase (exact terms in order within an
	  adjustable window).</para>
	  </listitem>
	  <listitem><para>Proximity (terms in any order within an
	  adjustable window).</para>
	  </listitem>
	  <listitem><para>Filename search with wildcards.</para>
	  </listitem>
	</itemizedlist>

      <para>Additional entry fields can be created by clicking the
      <guilabel>Add clause</guilabel> button.</para>

      <para>You can choose that all relevant fields will be combined
      by either an AND or an OR conjunction. All types of clauses
      except "phrase" and "near" can accept a mix of single words and
      phrases enclosed in double quotes. Stemming expansion will be
      performed for all terms not beginning with a capital letter,
      except for terms inside "phrase" clauses. Wildcards will be
      processed everywhere.</para>

      <para>Advanced search will also let you search for documents of
       specific mime types (ie: only <literal>text/plain</literal>, or
        <literal>text/HTML</literal> or
        <literal>application/pdf</literal> etc...). The state of the
        file type selection can be saved as the default (the file type
        filter will not be activated at program start-up, but the lists
        will be in the restored state).</para>

      <para>You can also restrict the search results
      to a sub-tree of the indexed area. If you need to do this often,
      you may think of setting up multiple indexes instead, as the
      performance will be much better.</para>

      <para>Click on the <guilabel>Start Search</guilabel> button in
      the advanced search dialog, or type <keycap>Enter</keycap> in
      any text field to start the search. The button in
      the main window always performs a simple search.</para>

      <para>Click on the <literal>Show query details</literal> link at
      the top of the result page to see the query expansion.</para>

    </sect1>

    <sect1 id="rcl.search.termexplorer">
      <title>The term explorer tool</title>

      <para>&RCL; automatically manages the expansion of search terms
      to their derivatives (ie: plural/singular, verb
      inflections). But there are other cases where the exact search
      term is not known. For example, you may not remember the exact
      spelling, or only know the beginning of the name.</para>

      <para>The term explorer tool (started from the toolbar icon or
      from the <guilabel>Term explorer</guilabel> entry of the
      <guilabel>Tools</guilabel> menu) can be used to search the full index
      terms list. It has three modes of operations:</para>
        <variablelist>

          <varlistentry>
	    <term>Wildcard</term>
            <listitem><para>In this mode of operation, you can enter a
            search string with shell-like wildcards (*, ?, []). ie:
            <replaceable>xapi*</replaceable> would display all index terms
            beginning with <replaceable>xapi</replaceable>. (More
            about wildcards <link
            linkend="rcl.search.wildcards">here</link>).</para></listitem> 
          </varlistentry>

          <varlistentry>
	  <term>Regular expression</term>
	  <listitem><para>This mode will accept a regular expression
            as input. Example:
            <replaceable>word[0-9]+</replaceable>. The expression is
            implicitely anchored at the beginning. Ie:
            <replaceable>press</replaceable> will match
            <replaceable>pression</replaceable> but not
            <replaceable>expression</replaceable>. You can use
            <replaceable>.*press</replaceable> to match the latter,
            but be aware that this will cause a full index term list
            scan, which can be quite long.</para>
	  </listitem>
          </varlistentry>
          <varlistentry>

	  <term>Stem expansion</term>
	  <listitem><para>This mode will perform the usual stem expansion
	  normally done as part user input processing. As such it is
	  probably mostly useful to demonstrate the process.
	  </para></listitem>
          </varlistentry>

          <varlistentry>
	    <term>Spelling/Phonetic</term> <listitem><para>In this
            mode, you enter the term as you think it is spelled, and
            &RCL; will do its best to find index terms that sound like
            your entry. This mode uses the
            <application>Aspell</application> spelling application,
            which must be installed on your system for things to
            work. The language which is used to build the dictionary
            out of the index terms (which is done at the end of an
            indexing pass) is the one defined by your NLS
            environment. Weird things will probably happen if
            languages are mixed up.</para></listitem>
          </varlistentry>
      </variablelist>

      <para>Note that in cases where &RCL; does not know the beginning
      of the string to search for (ie a wildcard expression like
      <replaceable>*coll</replaceable>), the expansion can take quite
      a long time because the full index term list will have to be
      processed. The expansion is currently limited at 200 results for
      wildcards and regular expressions.</para>
      
      <para>Double-clicking on a term in the result list will insert
      it into the simple search entry field. You can also cut/paste
      between the result list and any entry field (the end of lines
      will be taken care of).</para>

    </sect1>

    <sect1 id="rcl.search.wildcards">
      <title>More about wildcards</title>
      <para>All words entered in &RCL; search fields will be processed
      for wildcard expansion before the request is finally
      executed.</para>

      <para>The wildcard characters are:</para>

      <itemizedlist>
       <listitem><para><literal>*</literal> which matches 0 or more 
        characters.</para>
	</listitem>
	<listitem><para><literal>?</literal> which matches
           a single character.</para>
	</listitem>
        <listitem><para><literal>[]</literal> which allow
         defining sets of characters to be matched (ex:
         <literal>[</literal><userinput>abc</userinput><literal>]</literal> 
          matches a single character which may be 'a' or 'b' or 'c',
         <literal>[</literal><userinput>0-9</userinput><literal>]</literal>
         matches any number.</para>
	</listitem>
      </itemizedlist>

      <para>You should be aware of a few things before using
	wildcards.</para>

      <itemizedlist>
	<listitem><para>Using a wildcard character at the beginning of
	a word can make for a slow search because &RCL; will have to
	scan the whole index term list to find the matches.</para>
	</listitem>
	<listitem><para>Using a <literal>*</literal> at the end of a
	word can produce more matches than you would think, and
	strange search results. You can use the <link
	linkend="rcl.search.termexplorer">term explorer</link> tool to
	check what completions exist for a given term. You can also
	see exactly what search was performed by clicking on the link
	at the top of the result list. In general, for natural
	language terms, stem expansion will produce better results
	than an ending <literal>*</literal> (stem expansion is turned
	off when any wildcard character appears in the term).</para>
	</listitem>
      </itemizedlist>

    </sect1>

    <sect1 id="rcl.search.multidb">
      <title>Multiple databases</title>

      <para>Multiple &RCL; databases or indexes can be created by
      using several configuration directories which are usually set to
      index different areas of the file system. A specific index can
      be selected for updating or searching, using the
      <literal>RECOLL_CONFDIR</literal> environment variable or the
      <literal>-c</literal> option to <command>recoll</command> and
      <command>recollindex</command>.</para>

      <para>A <command>recollindex</command> program instance can only
      update one specific index.</para>

      <para>A <command>recoll</command> program instance is also
      associated with a specific index, which is the one to be
      updated by its indexing thread, but it can use any
      number of &RCL; indexes for searching. The external indexes
      can be selected through the <guilabel>external
      indexes</guilabel> tab in the preferences dialog.</para>

      <para>Index selection is performed in two phases. A set of all
      usable indexes must first be defined, and then the subset of
      indexes to be used for searching. Of course, these parameters
      are retained across program executions (there are kept
      separately for each &RCL; configuration). The set of all indexes
      is usually quite stable, while the active ones might typically
      be adjusted quite frequently.</para>

      <para>The main index (defined by
      <literal>RECOLL_CONFDIR</literal>) is always active. If this is
      undesirable, you can set up your base configuration to index
      an empty directory.</para>

      <para>As building the set of all indexes can be a little tedious
      when done through the user interface, you can use the
      <literal>RECOLL_EXTRA_DBS</literal> environment
      variable to provide an initial set. This might typically be
      set up by a system administrator so that every user does not
      have to do it. The variable should define a colon-separated list
      of index  directories, ie: 
     </para>
       <screen>export RECOLL_EXTRA_DBS=/some/place/xapiandb:/some/other/db</screen> 

      <para>A typical usage scenario for the multiple index feature
      would be for a system administrator to set up a central index
      for shared data, that you choose to search or not in addition to
      your personal data. Of course, there are other
      possibilities. There are many cases where you know the subset of
      files that should be searched, and where narrowing the search
      can improve the results. You can achieve approximately the same
      effect with the directory filter in advanced search, but
      multiple indexes will have much better performance and may be
      worth the trouble.</para>

    </sect1>

    <sect1 id="rcl.search.history">
      <title>Document history</title>

      <para>Documents that you actually view (with the internal preview
        or an external tool) are entered into the document history,
        which is remembered. You can display the history list by using
        the <guilabel>Tools/</guilabel><guilabel>Doc History</guilabel> menu
        entry.</para> 

    </sect1>

    <sect1 id="rcl.search.sort">
      <title>Sorting search results</title>

      <para>The documents in a result list are normally sorted in
      order of relevance. It is possible to specify different sort
      parameters by using the <guimenu>Sort parameters</guimenu>
      dialog (located in the <guimenu>Tools</guimenu>
      menu).</para>

      <para>The tool sorts a specified number of the most
      relevant documents in the result list, according to
      specified criteria. The currently available criteria are
      <emphasis>date</emphasis> and <emphasis>mime type</emphasis>.</para> 

      <para>The sort parameters stay in effect until they are explicitly
      reset, or the program exits. An activated sort is indicated in
      the result list header.</para>

    </sect1>

    <sect1 id="rcl.search.tips">
      <title>Search tips, shortcuts</title>

      <formalpara><title>Term completion</title>
	<para>Typing <keycap>Esc</keycap> <keycap>Space</keycap> in
	the simple search entry field while entering a word will
	either complete the current word if its beginning matches a
	unique term in the index, or open a window to propose a list
	of completions.</para>
      </formalpara>

      <formalpara><title>Picking up new terms from result or preview 
                   text</title>
	<para>Double-clicking on a word in the result list or in a
	preview window will copy it to the simple search entry field.</para>
      </formalpara>

      <formalpara><title>Disabling stem expansion</title>
      <para>Entering a capitalized word in any search field will prevent
        stem expansion (no search for
        <literal>gardening</literal> if you enter
        <literal>Garden</literal> instead of
        <literal>garden</literal>). This is the only case where
        character case should make a difference for a &RCL;
        search. You can also disable stem expansion or change the
        stemming language in the preferences.</para>
      </formalpara>

      <formalpara><title>Phrases</title>
      <para>A phrase can be looked for by enclosing it in double
        quotes. Example: <literal>"user manual"</literal> will look
        only for occurrences of <literal>user</literal> immediately
        followed by <literal>manual</literal>. You can use the
        <guilabel>This exact phrase</guilabel> field of the advanced
        search dialog to the same effect. Phrases can be entered along
        simple terms in all simple or advanced search entry fields
        (except <guilabel>This exact phrase</guilabel>).</para>
      </formalpara>

      <formalpara><title>Browsing the result list inside a preview 
                   window (1.5)</title>
       <para>Entering <keycap>Shift-Down</keycap> or <keycap>Shift-Up</keycap>
       (<keycap>Shift</keycap> + an arrow key) in a preview window will
       display the next or the previous document from the result
       list. Any secondary search currently active will be executed on
       the new document.</para>
      </formalpara>

      <formalpara><title>Forced opening of a preview window (1.6)</title>
       <para>You can use <keycap>Shift</keycap>+Click on a result list
       <literal>Preview</literal> link to force the creation of a
       preview window instead of a new tab in the existing one.</para>
      </formalpara>

      <formalpara><title>AutoPhrases (1.5)</title>
      <para>This option can be set in the preferences dialog. If it is
      set, a phrase will be automatically built and added to simple
      searches when looking for <literal>Any terms</literal>. This
      will not change radically the results, but will give a relevance
      boost to the results where the search terms appear as a
      phrase. Ie: searching for <literal>virtual reality</literal>
      will still find all documents where either
      <literal>virtual</literal> or <literal>reality</literal> or 
      both appear, but those which contain <literal>virtual
      reality</literal> should appear sooner in the list.</para>

      <formalpara><title>Finding related documents</title>
	<para>Selecting the <guilabel>Find similar documents</guilabel> entry
	in the result list paragraph right-click menu will select a
	set of "interesting" terms from the current result, and insert
	them into the simple search entry field. You can then possibly
	edit the list and start a search to find documents which may
	be apparented to the current result.</para>
      </formalpara>

      <formalpara><title>File names</title>
        <para>File names are added as terms during indexing, and you can
        specify them as ordinary terms in normal search fields (&RCL; used
        to index all directories in the file path as terms. This has been
        abandoned as it did not seem really useful). Alternatively, you
        can use the specific file name search which will
        <emphasis>only</emphasis> look for file names and can use wildcard
        expansion.</para>
      </formalpara>

      <formalpara><title>Query explanation</title>
        <para>You can get an exact description of what the query
        looked for, including stem expansion, and Boolean operators
        used, by clicking on the result list header.</para>
      </formalpara>

      <formalpara><title>Closing previews</title> 
       <para>Entering <keycap>^W</keycap> in a tab will
        close it (and, for the last tab, close the preview
        window). Entering <keycap>Esc</keycap> will close the preview
        window and all its tabs.</para>
      </formalpara>

      <formalpara><title>Quitting</title>
      <para>Entering <keycap>^Q</keycap> almost anywhere will
        close the application.</para>
      </formalpara>

    </sect1>

    <sect1 id="rcl.search.custom">
      <title>Customizing the search interface</title>

      <para>It is possible to customize some aspects of the search
      interface by using <guimenu>Query configuration</guimenu> entry
      in the <guimenu>Preferences</guimenu> menu.</para>

      <para>There are two tabs in the dialog, dealing with the
      interface itself, and with the parameters used for searching and
      returning results.</para> 

      <formalpara><title>User interface parameters:</title>
	<para>
      <itemizedlist>

	<listitem><para><guilabel>Number of results in a result
	page</guilabel></para> 
	</listitem>

	<listitem><para><guilabel>Result list font</guilabel>: There
	is quite a lot of information shown in the result list, and
	you may want to customize the font and/or font size. The rest
	of the fonts used by &RCL; are determined by your generic QT
	config (try the <command>qtconfig</command> command.</para>
	</listitem>

	<listitem><para><guilabel>Result paragraph format
	string</guilabel>: allows you to change the presentation of
	each result list entry. This is a qt-html string where the
	following printf-like <literal>%</literal> substitutions will
	be performed:
        <itemizedlist>
          <listitem>
	    <formalpara><title>%A</title><para>Abstract</para></formalpara>
	  </listitem>
	  <listitem><formalpara><title>%D</title><para>Date</para></formalpara>
	  </listitem>
	  <listitem><formalpara><title>%K</title><para>Keywords (if
	  any)</para></formalpara> 
	  </listitem>
	  <listitem><formalpara><title>%L</title><para>Preview and
	  Edit links</para></formalpara> 
	  </listitem>
	  <listitem><formalpara><title>%M</title><para>Mime
		  type</para></formalpara> 
	  </listitem>
	  <listitem><formalpara><title>%N</title><para>result Number
		  </para></formalpara> 
	  </listitem>
	  <listitem><formalpara><title>%R</title><para>Relevance
	  percentage</para></formalpara> 
	  </listitem>
	  <listitem><formalpara><title>%S</title><para>Size
	  information</para></formalpara> 
	  </listitem>
	  <listitem><formalpara><title>%T</title><para>Title</para>
		    </formalpara> 
	  </listitem>
	  <listitem><formalpara><title>%U</title><para>Url</para></formalpara>
	  </listitem>
	</itemizedlist>
        The default value for the string is:
        <programlisting>%R %S %L &amp;nbsp;&amp;nbsp;&lt;b>%T&lt;/b>&lt;br>
%M&amp;nbsp;%D&amp;nbsp;&amp;nbsp;&amp;nbsp;&lt;i>%U&lt;/i>&lt;br>
%A %K
        </programlisting>
        You may, for example, try the following for a more web-like
        experience:
        <programlisting>&lt;u>&lt;b>&lt;a href="P%N"&gt;%T&lt;/a&gt;&lt;/b>&lt;/u>&lt;br>
%A&lt;font color=#008000>%U - %S&lt;/font> - %L
        </programlisting>
	The format of the Preview and Edit links is 
	<literal>&lt;a href="P<replaceable>docnum</replaceable>"&gt;</literal>
	and 
        <literal>&lt;a href="E<replaceable>docnum</replaceable>"&gt;</literal>
        where <replaceable>docnum</replaceable> is what %N would
        print. This makes the title a preview link in the above format.
	</para>
	</listitem>

	<listitem><para><guilabel>HTML help browser</guilabel>: this
	will let you chose your preferred browser which will be
	started from the <guimenu>Help</guimenu> menu to read the user
	manual. You can enter a simple name if the command is in your
	PATH, or browse for a full pathname.</para>
	</listitem>

	<listitem><para><guilabel>Show document type icons in result
	list</guilabel>: icons in the result list can be turned
	off. They take quite a lot of space and convey relatively
	little useful information.</para>
	</listitem>

	<listitem><para><guilabel>Auto-start simple search on
	white space entry</guilabel>: if this is checked, a search will
	be executed each time you enter a space in the simple search
	input field. This lets you look at the result list as you
	enter new terms. This is off by default, you may like it or
	not...</para> 
	</listitem>

      </itemizedlist>
      </para>
      </formalpara>


      <formalpara><title>Search parameters:</title>
	<para>
      <itemizedlist>

	<listitem><para><guilabel>Stemming language</guilabel>:
	stemming obviously depends on the document's language. This
	listbox will let you chose among the stemming databases which
	were built during indexing (this is set in the <link
	linkend="rcl.install.config.recollconf">main configuration
	file</link>), or later added with
        <command>recollindex -s</command> (See the recollindex
        manual). Stemming languages which are dynamically added will be
        deleted at the next indexing pass unless they are also added in
        the configuration file.</para>
	</listitem>

	<listitem><para><guilabel>Dynamically build
	abstracts</guilabel>: this decides if &RCL; tries to build
	document abstracts when displaying the result list. Abstracts
	are constructed by taking context from the document
	information, around the search terms. This can slow down
	result list display significantly for big documents, and you
	may want to turn it off.</para>
	</listitem>

	<listitem><para><guilabel>Replace abstracts from
	documents</guilabel>: this decides if we should synthesize and
	display an abstract in place of an explicit abstract found
	within the document itself.</para>
	</listitem>

	<listitem><para><guilabel>Synthetic abstract size</guilabel>:
	adjust to taste...</para>
	</listitem>

	<listitem><para><guilabel>Synthetic abstract context
	words</guilabel>: how many words should be displayed around
	each term occurrence.</para>
	</listitem>

      </itemizedlist>
       </para>
      </formalpara>

      <formalpara id="rcl.search.custom.extradb">
	<title>External indexes:</title> 
      <para>This panel will let you browse for additional indexes
      that you may want to search. External indexes are designated by
      their database directory (ie:
      <filename>/home/someothergui/.recoll/xapiandb</filename>,
      <filename>/usr/local/recollglobal/xapiandb</filename>).</para>

      <para>Once entered, the indexes will appear in the
	<guilabel>External indexes</guilabel> list, and you can
	chose which ones you want to use at any moment by checking or
	unchecking their entries.</para> 

      <para>Your main database (the one the current configuration
      indexes to), is always implicitly active. If this is not
      desirable, you can set up your configuration so that it indexes,
      for example, an empty directory.</para>

    </sect1>

  </chapter>


  <chapter id="rcl.install">
    <title>Installation</title>

    <sect1 id="rcl.install.binary">
      <title>Installing a prebuilt copy</title>

      <para>Recoll binary installations are always linked statically
        to the xapian libraries, and have no other dependencies. You
        will only have to check or install 
        <link linkend="rcl.install.external">supporting
        applications</link> for the file types that you want to index
        beyond text, HTML and mail files.</para> 

      <sect2 id="rcl.install.binary.package">
        <title>Installing through a package system</title>

        <para>If you use a BSD-type port system or a
         prebuilt package (RPM or other), just follow the usual
         procedure, and maybe have a look at the <link
         linkend="rcl.install.config">configuration
         section</link> (but this may not be necessary for a quick
         test with default parameters).</para>

      </sect2>

      <sect2 id="rcl.install.binary.rcl">
        <title>Installing a prebuilt &RCL;</title>

      <para>The unpackaged binary versions are just compressed tar
        files of a build tree, where only the useful parts were kept
        (executables and sample configuration).</para>

      <para>The executable binary files are built with a static link to
        libxapian and libiconv, to make installation easier (no
        dependencies). However, this also means that you cannot change
        the versions which are used.</para> 

      <para>After extracting the tar file, you can proceed with
        <link linkend="rcl.install.building.install">installation</link> as
        if you had built the package from source (that is, just type
        <literal>make install</literal>). The binary trees are built for
        installation to	<filename>/usr/local</filename>.</para>

	<para>You may then need to install external applications to process
	some file types that you want indexed (ie: acrobat, 
	postscript&nbsp;...). See next section.</para> 

	<para>Finally, you may want to have a look at the <link
        linkend="rcl.indexing.config">configuration section</link>.</para>

      </sect2>
      </sect1>

    <sect1 id="rcl.install.external">
      <title>Supporting packages</title>

	<para>&RCL; uses external applications to index some file
        types. You need to install them for the file types that you wish to
        have indexed (these are run-time dependencies. None is needed for
        building &RCL;):</para>

      <itemizedlist>

        <listitem><para>Openoffice: supported natively, but needs the
        <command>unzip</command> command to be installed.</para>
          </listitem>

        <listitem><para>PDF: pdftotext is part of the <ulink
            url="http://www.foolabs.com/xpdf/">Xpdf</ulink> package.</para>
          </listitem>

        <listitem><para>Postscript: <ulink
          url="http://www.cs.wisc.edu/~ghost/doc/pstotext.htm">
            pstotext</ulink>.</para>
          </listitem>

        <listitem><para>MS Word: <ulink url="http://www.winfield.demon.nl"> 
            antiword</ulink>.</para>
          </listitem>

        <listitem><para>MS Excel and PowerPoint: 
           <ulink url="http://www.45.free.net/~vitus/software/catdoc/"> 
            catdoc</ulink>.</para>
          </listitem>

        <listitem>
            <para>RTF: <ulink
            url="http://www.gnu.org/software/unrtf/unrtf.html">unrtf</ulink>
          </para>
	</listitem>

	<listitem>
            <para>dvi: <ulink
	       url="http://www.radicaleye.com/dvips.html">dvips</ulink></para>
        </listitem>

	<listitem>
            <para>djvu: 
	    <ulink
	       url="http://djvulibre.djvuzone.org/doc/index.html">DjVuLibre
	    </ulink></para>
        </listitem>
          
        <listitem><para>MP3: &RCL; will use the
        <command>id3info</command> command from the <ulink
        url="http://id3lib.sourceforge.net/">id3lib</ulink> package to
        extract tag information. Without it, only the file names will
        be indexed.</para>
          </listitem>
        </itemizedlist>

	<para>Text, HTML, mail folders Openoffice and Scribus files
	are processed internally. Lyx is used to index Lyx files. Many
	filters need <command>sed</command> and <command>awk</command>.
	</para>

    </sect1>


      <sect1 id="rcl.install.building">
      <title>Building from source</title>

      <sect2 id="rcl.install.building.prereqs">
        <title>Prerequisites</title>

      <para>At the very least, you will need to download and install the
        <ulink url="http://www.xapian.org">xapian core package</ulink>
        (&RCL; development currently uses version 0.9.5), and the <ulink
        url="http://www.trolltech.com/products/qt/index.html">qt
          run-time and development packages</ulink> (&RCL; development
          currently uses version 3.3.5, but any 3.3 version is
          probably OK).</para> 

      <para>You will most probably be able to find a binary package for
        <application>qt</application> for your system. You may have to
        compile &XAP; but this is not difficult (if you are using
        <application>FreeBSD</application>, there is a port).</para>

      <para>You may also need 
        <ulink
        url="http://www.gnu.org/software/libiconv/">libiconv</ulink>. &RCL;
        currently uses version 1.9 (this should not be critical). On
        <application>Linux</application> systems, the iconv interface
        is part of libc and you should not need to do anything
        special.</para>
      
      <sect2 id="rcl.install.building.build">
        <title>Building</title>

      <para>&RCL; has been built on
        Linux (redhat7.3, mandriva 2005/6, Fedora Core 3/4/5), FreeBSD and
        Solaris 8. If you build on another system, <ulink
        url="mailto:jean-francois.dockes@wanadoo.fr">I would very much
        welcome patches</ulink>.</para>

      <para>Depending on the <application>qt</application>
      configuration on your system, you may have to set the
      <literal>QTDIR</literal> and <literal>QMAKESPECS</literal>
      variables in your environment:</para>
        <itemizedlist>
          <listitem><para><literal>QTDIR</literal> should point to the
          directory above the one that holds the qt include files (ie:
          if <filename>qt.h</filename> is
          <filename>/usr/local/qt/include/qt.h</filename>, QTDIR
          should be <filename>/usr/local/qt</filename>).</para>
          </listitem>
          <listitem><para><literal>QMAKESPECS</literal> should
          be set to the name of one of the
          <application>qt</application> mkspecs sub-directories (ie:
          linux-g++).</para> 
          </listitem>
        </itemizedlist>

        <para>On many Linux systems, <literal>QTDIR</literal> is set
        by the login scripts, and <literal>QMAKESPECS</literal> is not
        needed because there is a <filename>default</filename> link in
        <filename>mkspecs/</filename>.</para>

	<formalpara><title>Configure
	options:</title><para><literal>--without-aspell</literal> 
	will disable the code for phonetic matching of search
	terms. <literal>--with-fam</literal> or
	<literal>--with-inotify</literal> will enable the code for
	real time indexing. Inotify support is enabled by default on
	recent Linux systems.</para>

      <para>Normal procedure:</para>
      <screen>
        <userinput>cd recoll-xxx</userinput>
        <userinput>configure</userinput>
        <userinput>make</userinput>
        <userinput>(practices usual hardship-repelling invocations)</userinput>
      </screen>


      <para>There little auto-configuration. The
        <command>configure</command> script will mainly link one of
        the system-specific files in the <filename>mk</filename>
        directory to <filename>mk/sysconf</filename>. If your system
        is not known yet, it will tell you as much, and you may want
        to manually copy and modify one of the existing files (the new
        file name should be the output of <command>uname -s</command>).</para>
      </sect2>

      <sect2 id="rcl.install.building.install">
        <title>Installation</title>
      
      <para>Either type <userinput>make install</userinput> or execute
      <userinput>recollinstall
      <replaceable>prefix</replaceable></userinput>, in the root 
        of the source tree. This will copy the commands to
        <filename><replaceable>prefix</replaceable>/bin</filename>
        and the sample configuration files, scripts and other shared
        data to
        <filename><replaceable>prefix</replaceable>/share/recoll</filename>.</para>
	<para>If the installation prefix given to
	<command>recollinstall</command> is different from what was
	specified when executing <command>configure</command>, you
	will have to set the <literal>RECOLL_DATADIR</literal>
	environment variable to indicate where the shared data is to
	be found.</para>

	<para>You can then proceed to <link
       linkend="rcl.install.config">configuration</link>. </para>

      </sect2>
    </sect1>

    <sect1 id="rcl.install.config">
      <title>Configuration overview</title>

      <para>Most of the parameters specific to the
         <command>recoll</command> GUI are set through the
          <guilabel>Preferences</guilabel> menu and stored in the
          standard QT place
          (<filename>$HOME/.qt/recollrc</filename>). You probably do not
          want to edit this by hand.</para>

      <para>For other options, &RCL; uses text configuration
        files. You will have to edit them by hand for 
        now (there is still some hope for a GUI configuration tool
        in the future). The most accurate documentation for the
        configuration parameters is given by comments inside the default
        files, and we will just give a general overview here.</para>

      <para>There are two sets of configuration files. The system-wide
      files are kept in a directory named like
      <filename>/usr/[local/]share/recoll/examples</filename>, 
      they define default values for the system. A parallel set of
      files exists by default in the <filename>.recoll</filename> directory
      in your home. This directory can be changed with the 
      <literal>RECOLL_CONFDIR</literal> environment variable or the -c
      option parameter to <command>recoll</command> and
      <command>recollindex</command>.</para> 

      <para>If the <filename>.recoll</filename> directory does not
      exist when <command>recoll</command> or 
        <command>recollindex</command> are started, it
        will be created with a set of empty configuration files.
        <command>recoll</command> will give you a
        chance to edit the configuration file before starting
        indexing. <command>recollindex</command> will
        proceed immediately.</para>
      

        <para>All configuration files share the same format. For
        example, a short extract of the main configuration file might
        look as follows:</para> 
        <programlisting>
        # Space-separated list of directories to index.
        topdirs =  ~/docs /usr/share/doc

        [~/somedirectory-with-utf8-txt-files]
        defaultcharset = utf-8
        </programlisting>

        <para>There are three kinds of lines: </para>
        <itemizedlist>
          <listitem><para>Comment (starts with
          <emphasis>#</emphasis>) or empty.</para> 
          </listitem>
          <listitem><para>Parameter affectation (<emphasis>name =
          value</emphasis>).</para> 
          </listitem>
          <listitem><para>Section definition
          ([<emphasis>somedirname</emphasis>]).</para> 
          </listitem>
        </itemizedlist>

        <para>Section definitions allow redefining some parameters for
        a directory sub-tree. They stay in effect until another
        section definition, or the end of file, is encountered. Some
        of the parameters used for indexing are looked up
        hierarchically from the current directory location
        upwards. Not all parameters can be meaningfully redefined,
        this is specified for each in the next section. </para>

        <para>The tilde character (~) is expanded in file names to the
        name of the user's home directory.</para>
        
        <para>White space is used for separation inside  lists.
        List elements with embedded spaces can be quoted using
        double-quotes.</para>

      <sect2 id="rcl.install.config.recollconf">
        <title>Main configuration file</title>

        <para><filename>recoll.conf</filename> is the main
         configuration file. It defines things like
         what to index (top directories and things to ignore), and the
         default character set to use for document types which do not
         specify it internally.</para>

        <para>The default configuration will index your home
         directory. If this is not appropriate, start
         <command>recoll</command> to create a blank 
         configuration, click <guimenu>Cancel</guimenu>, and edit
         the configuration file before restarting the command. This
         will start the initial indexing, which may take some time.</para>
        
        <para>Paramers:</para>

        <variablelist>

          <varlistentry id="rcl.install.config.recollconf.topdirs">
	    <term><literal>topdirs</literal></term>
            <listitem><para>Specifies the list of directories or files to
            index (recursively for directories). The indexer will not
            follow symbolic links inside the indexed trees. If an entry in
            the <literal>topdirs</literal> list is a symbolic link,
            indexing will not start and will generate an error.</para>
            </listitem> 
          </varlistentry>

          <varlistentry><term><literal>dbdir</literal></term>
            <listitem><para>The name of the Xapian data directory. It
            will be created if needed when the index is
            initialized. If this is not an absolute path, it will be
            interpreted relative to the configuration directory. The
            value can have embedded spaces but starting or trailing
            spaces will be trimmed. You cannot use quotes here.</para>
            </listitem>
          </varlistentry>

          <varlistentry><term><literal>skippedNames</literal></term>
            <listitem>
              <para>A space-separated list of patterns for
               names of files or directories that should be completely
               ignored. The list defined in the default file is: </para>
<programlisting>
*~ #* bin CVS  Cache caughtspam  tmp
</programlisting>
              <para>The list can be redefined for sub-directories, but is only
               actually changed for the top level ones in
               <literal>topdirs</literal>.</para>
               <para>The top-level directories are not affected by this
                list (that is, a directory in <literal>topdirs</literal>
                might match and would still be indexed).</para>
                <para>The list in the default configuration does not
                exclude hidden directories (names beginning with a
                dot), which means that it may index quite a few things
                that you do not want. On the other hand, mail user
                agents like <application>thunderbird</application>
                usually store messages in hidden directories, and you
                probably want this indexed. One possible solution is to
                have <filename>.*</filename> in
                <literal>skippedNames</literal>, and add things like
                <filename>~/.thunderbird</filename> or
                <filename>~/.evolution</filename> in
                <literal>topdirs</literal>.</para> 
            </listitem>
          </varlistentry>

          <varlistentry><term><literal>loglevel,daemloglevel</literal></term>
            <listitem><para>Verbosity level for recoll and
            recollindex. A value of 4 lists quite a lot of
            debug/information messages. 2 only lists errors. The
            <literal>daem</literal>version is specific to the indexing monitor
            daemon.</para>
            </listitem>
          </varlistentry>

          <varlistentry><term><literal>logfilename,
          daemlogfilename</literal></term> 
            <listitem><para>Where the messages should go. 'stderr' can
            be used as a special value, and is the default. The
            <literal>daem</literal>version is specific to the indexing monitor
            daemon.</para>
            </listitem>
          </varlistentry>

          <varlistentry><term><literal>filtersdir</literal></term>
            <listitem><para>A directory to search for the external
            filter scripts used to index some types of files. The
            value should not be changed, except if you want to modify
            one of the default scripts. The value can be redefined for
            any sub-directory. </para>
            </listitem>
          </varlistentry>

          <varlistentry><term><literal>indexstemminglanguages</literal></term>
            <listitem><para>A list of languages for which the stem
            expansion databases will be built. See recollindex(1) for
            possible values. You can add a stem expansion database for
            a different language by using <command>recollindex
            -s</command>, but it will be deleted during the next
            indexing. Only languages listed in the configuration
            file are permanent.</para>
            </listitem>
          </varlistentry>

         
          <varlistentry><term><literal>defaultcharset</literal></term>
            <listitem><para>The name of the character set used for
            files that do not contain a character set definition (ie:
            plain text files). This can be redefined for any
            sub-directory. If it is not set at all, the character set
            used is the one defined by the nls environment (LC_ALL,
            LC_CTYPE, LANG), or iso8859-1 if nothing is set.</para> 

          <varlistentry><term><literal>guesscharset</literal></term>
            <listitem><para>Decide if we try to guess the character
            set of files if no internal value is available (ie: for
            plain text files). This does not work well in general, and
            should probably not be used. </para>
            </listitem>
          </varlistentry>

          <varlistentry><term><literal>usesystemfilecommand</literal></term>
            <listitem><para>Decide if we use the <command>file -i</command>
            system command as a final step for determining the mime
            type for a file (the main procedure uses suffix
            associations as defined in the  <filename>mimemap</filename>
            file). This can be useful for files with suffix-less names,
            but it will also cause the indexing of many bogus "text"
            files.</para> 
            </listitem>
          </varlistentry>

	  <varlistentry><term><literal>indexallfilenames</literal></term>
	    <listitem><para>&RCL; indexes file names in a special
	    section of the database to allow specific file names
	    searches using wild cards. This parameter decides if 
            file name indexing is performed only for files with mime
            types that would qualify them for full text indexing, or
            for all files inside the selected subtrees, independently of
            mime type.</para>
	    </listitem>
	  </varlistentry>

	  <varlistentry><term><literal>idxabsmlen</literal></term>
	    <listitem><para>&RCL; stores an abstract for each indexed
	    file inside the database. This is so that they can be
	    displayed inside the result lists without decoding the
	    original file. This parameter defines the size of the
	    stored abstract (which can come from an actual section or
	    just be the beginning of the text). The default value is 250.
            </para>
	    </listitem>
	  </varlistentry>

          <varlistentry><term><literal>iconsdir</literal></term>
            <listitem><para>The name of the directory where
            <command>recoll</command> result list icons are
            stored. You can change this if you want different
            images.</para>
            </listitem>
          </varlistentry>

        </variablelist>

      </sect2>

      <sect2 id="rclinstall.config.mimemap">
        <title>The mimemap file</title>

        <para><filename>mimemap</filename> specifies the
        file name extension to mime type mappings.</para> 

	<para>For file names without an extension, or with an unknown
        one, the system's <command>file -i</command> command will be
        executed to determine the mime type (this can be switched off
        inside the main configuration file).</para>

        <para>The mappings can be specified on a per-subtree basis,
        which may be useful in some cases. Example:
        <application>gaim</application> logs have a
        <filename>.txt</filename> extension but 
        should be handled specially, which is possible because they
        are usually all located in one place.</para>

        <para><filename>mimemap</filename> also has a
        <literal>recoll_noindex</literal> variable which is a list of
        suffixes. Matching files will be skipped (which avoids
        unnecessary decompressions or <command>file</command>
        executions). This is partially redundant with
        <literal>skippedNames</literal> in the main configuration
        file, with two differences: it will not affect directories,
        and it cannot be made dependant on the file-system location
        (it is a configuration-wide parameter). You could accomplish
        with <literal>skippedNames</literal> anything that
        <literal>recoll_noindex</literal> does. The latter is used
        mostly for things known to be unindexable by a given &RCL;
        version. Having it there avoids cluttering the more
        user-oriented and locally customized
        <literal>skippedNames</literal>.</para>

      </sect2>

      <sect2 id="rclinstall.config.mimeconf">
        <title>The mimeconf file</title>

        <para><filename>mimeconf</filename> specifies how the
         different mime types are handled for indexing, and which icons
	 are displayed in the <command>recoll</command> result lists.</para>

        <para>Changing the parameters in the [index] section is
         probably not a good idea except if you are a &RCL;
         developer.</para> 

        <para>The [icons] section allows you to change the icons which
         are displayed by <command>recoll</command> in the result
         lists (the values are the basenames of the png images inside
         the <filename>iconsdir</filename> directory (specified in
         <filename>recoll.conf</filename>).</para>

      </sect2>
      <sect2 id="rclinstall.config.mimeview">
        <title>The mimeview file</title>

        <para><filename>mimeview</filename> specifies which programs
        are started when you click on an <guilabel>Edit</guilabel>
        link in a result list. Ie: HTML is normally displayed using
         <application>firefox</application>, but you may prefer
         <application>Konqueror</application>, your
         <application>openoffice.org</application> 
         program might be named <command>oofice</command> instead of
         <command>openoffice</command> etc. 
         </para>

        <para>Changes to this file can be done by direct editing, or
        through the <command>recoll</command> user preferences dialog.</para>

	<para>As for the other configuration files, the normal usage
	is to have a <filename>mimeview</filename> inside your own
	configuration directory, with just the non-default entries,
	which will override those from the central configuration
	file.</para>
	<para>Please note that these entries must be placed under a
	<literal>[view]</literal> section.</para>

      </sect2>

    </sect1>
  </chapter>

</book>