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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 1.17 2006-09-15 16:50:44 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>
        (exemple: floor, floors, floored, floorings...). &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 accomodate for misspellings or
        phonetic searches. &RCL; currently does not support these
        features.</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 capitalisation 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 reindexing.  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 overriden by values that you set inside your personal
        configuration, found by default in the
        <filename>.recoll</filename> subdirectory 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.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 on by specifying an option to the indexing command
      (<command>recollindex -z</command>).</para> 

      <para>&RCL; indexing takes place at discrete times. There is
      currently no interface to real time file modification
      monitors. The typical usage is to have a nightly indexing run
      <link linkend="rcl.indexing.automat">programmed</link> into your
      <command>cron</command> file.</para>

      <sidebar><para>There is nothing in &RCL; and &XAP;
      that would prevent interfacing with a real time file
      modification monitor, but this would tend to consume significant
      system resources for dubious gain, because you rarely need a
      full text search to find documents you just
      modified. <command>recollindex -i</command>  can be used to add
      individual files to the index if you want to play with this, see
      the manual page.</para>
      </sidebar>

      <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. You would use the
      <literal>RECOLL_CONFDIR</literal> environment variable or the
      <literal>-c</literal> <replaceable>confdir</replaceable> option
      to <command>recollindex</command> to indicate which
      configuration to process. The <command>recoll</command> search
      program can use any selection of the existing databases for each
      search, this is configurable inside the user interface.</para>
    </sect1>

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

      <para>The default location for the index data is the
      <filename>$HOME/.recoll/xapiandb/</filename> directory. This can
      be changed by setting the <literal>RECOLL_CONFDIR</literal>
      environment variable, or by specifying the
      <literal>dbdir</literal> parameter in the configuration file
      (see the <link linkend="rcl.install.config.recollconf">configuration
      section</link>).</para>

      <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 will be 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 subdirectory 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>Values set in the system-wide configuration file (named
      like
      <filename>/usr/[local/]share/recoll/examples/recoll.conf</filename>)
      can be overriden by those set in the personal one, named
        <filename>$HOME/.recoll/recoll.conf</filename> by default or
        <filename>$RECOLL_CONFDIR/recoll.conf</filename> if
          RECOLL_CONFDIR is set.</para>

      <para>The most accurate documentation for editing the file is
      given by comments inside the central one.  If you want to adjust
      the configuration before indexing, just click
      <guilabel>Cancel</guilabel> when the program asks if it should
      start initial indexing. This will have created a
      <filename>.recoll</filename> directory containing empty
      configuration files.</para>

      <para>The configuration is also documented inside the <link
      linkend="rcl.install.config.recollconf">installation chapter</link> of
      this document, or in the recoll.conf(5) man page.</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.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 cancelled).</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 clear
        everything 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> 

    </sect1>

    <sect1 id="rcl.indexing.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>

    </sect1>

  </chapter>

  <chapter id="rcl.search">
    <title>Search</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>Any
        term</guilabel>. This will look for documents with any of the
        search terms (the ones with more terms will get better scores). 
        <guilabel>All terms</guilabel> will ensure
        that only documents with all the terms will be
        returned. <guilabel>File name</guilabel> will specifically
        look for file names, and allows using wildcards
        (<literal>*</literal>, <literal>?</literal> ,
        <literal>[]</literal>). </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/filename).</para>

      <para>Hitting <keycap>^Tab</keycap> (<keycap>Ctrl</keycap> +
        <keycap>Tab</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. Clicking the
       <literal>Edit</literal> link will attempt to start an external
       viewer (have a look at the <filename>mimeconf</filename>
       configuration file to see how these are configured).</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.mimeconf">
       <filename>mimeconf</filename></link> configuration files.</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
          popup 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>
	</itemizedlist>

	<para>The <guilabel>Preview</guilabel> and
          <guilabel>Edit</guilabel> entries do the same thing as the 
          corresponding links. The two following entries will copy either
          an url or the file path to the clipboard, for pasting into
          another application.</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>

      </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.</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 occurence. 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 positionned
      at the first occurrence of the search string.</para>

    </sect1>

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

      <para>The advanced search dialog has fields that will allow a more
        refined search, looking for documents with all given elements, a
        given exact phrase, none of the given elements, or a given file
        name (with wildcard expansion). All relevant fields will be
        combined by an implicit AND clause. All fields except "Exact
        phrase" can accept a mix of single words and phrases enclosed
        in double quotes.</para>

      <para>Advanced search will 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 startup, but the lists
        will be in the restored state).</para>

      <para>You can also restrict the search results
      to a subtree 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.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 may 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 you want to be searched for a given query, and where
      restricting the query will much improve the precision of the
      results. This can also be performed 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 explicitely
      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>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.</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 search entry fields (except <guilabel>This
        exact phrase</guilabel>).</para>
      </formalpara>

      <formalpara><title>AutoPhrases</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>Term completion</title>
	<para>Typing <keycap>^TAB</keycap> (<keycap>Control</keycap> +
	<keycap>Tab</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 for search from displayed
      documents</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>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>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>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
        abandonned 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>Quitting</title>
      <para>Entering <keycap>^Q</keycap> almost anywhere will
        close the application.</para>
      </formalpara>

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

      <formalpara><title>List browsing in preview</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>

    </sect1>

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

      <para>It is possible to customise 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 customise 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>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
	whitespace 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 synthetize 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>All indexes</guilabel> list, and you can
	chose which ones you want to use at any moment by tranferring
	them to/from the <guilabel>Active indexes</guilabel>
	list.</para> 
      <para>Your main database (the one the current configuration
      indexes to), is always implicitely 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.</para> 

	<para>The binary trees are built for installation to
	<filename>/usr/local</filename>.</para>
      </sect2>


    </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
          runtime 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, Fedora Core 3), 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:
          qt.h).</para>
          </listitem>
          <listitem><para><literal>QMAKESPECS</literal> should
          be set to the name of one of the
          <application>qt</application> mkspecs subdirectories (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>

        <para>The &RCL; <command>configure</command> script does a
        better job of checking these variables after release
        1.1.1. Before this, unexplained errors will occur during
        compilation if the environment is not set up. Also, for 1.1.0 the
        <command>qmake</command> command should be in your PATH (later
        releases can also find it in
        <filename>$QTDIR/bin</filename>).</para> 

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


      <para>There little autoconfiguration. 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.external">
      <title>Packages needed for external file types</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>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 filenames will
        be indexed.</para>
          </listitem>
        </itemizedlist>

	<para>Text, Html, mail folders and Openoffice files are
	processed internally.</para>
    </sect1>

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

      <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>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>All configuration files share the same format. For
        exemple, 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 lines allow redefining some parameters for a
        directory subtree. Some of the parameters used for indexing
        are looked up hierarchically from the more to the less
        specific. 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.
        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><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.</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 subdirectories, 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 <userinput>.*</userinput> 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</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. </para>
            </listitem>
          </varlistentry>

          <varlistentry><term><literal>logfilename</literal></term>
            <listitem><para>Where the messages should go. 'stderr' can
            be used as a special value, and is the default. </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 subdirectory. </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
            subdirectory. 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 suffixless 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, independant 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 (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 can be changed for any
        subdirectory.</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 for
         display.</para>

        <para>Changing the indexing parameters is probably not a
         good idea except if you are a &RCL; developper.</para>

        <para>You may want to adjust the external viewers defined in
         (ie: html is either previewed internally or displayed using
         <application>firefox</application>, but you may prefer
         <application>mozilla</application>, your
         <application>openoffice.org</application> 
         program might be named <command>oofice</command> instead of
         <command>openoffice</command> ...). Look
         for the <literal>[view]</literal> section.</para>

        <para>You can also 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>

    </sect1>
  </chapter>

</book>