diff --git a/doc/xmllint.xml b/doc/xmllint.xml
index 904f43f..10f5d82 100644
--- a/doc/xmllint.xml
+++ b/doc/xmllint.xml
@@ -3,6 +3,8 @@
    href="http://docbook.sourceforge.net/release/xsl/current/manpages/docbook.xsl"?>
 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN"
     "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" [
+    
+    <!ENTITY xmllint "<command>xmllint</command>">
 ]>
 <refentry>
   <refentryinfo>
@@ -45,70 +47,74 @@
   <refsynopsisdiv>
     <cmdsynopsis>
       <command>xmllint</command>
-      <group>
-	<arg>--version</arg>
-	<arg>--debug</arg>
-	<arg>--shell</arg>
-	<arg>--debugent</arg>
-	<arg>--copy</arg>
-	<arg>--recover</arg>
-	<arg>--noent</arg>
-	<arg>--noout</arg>
-	<arg>--nonet</arg>
-	<arg>--path <replaceable>paths</replaceable></arg>
-	<arg>--load-trace</arg>
-	<arg>--htmlout</arg>
-	<arg>--nowrap</arg>
-	<arg>--valid</arg>
-	<arg>--postvalid</arg>
-	<arg>--dtdvalid <replaceable>URL</replaceable></arg>
-	<arg>--dtdvalidfpi <replaceable>FPI</replaceable></arg>
-	<arg>--timing</arg>
-	<arg>--output <replaceable>file</replaceable></arg>
-	<arg>--repeat</arg>
-	<arg>--insert</arg>
-	<arg>--compress</arg>
-	<arg>--html</arg>
-	<arg>--xmlout</arg>
-	<arg>--push</arg>
-	<arg>--memory</arg>
-	<arg>--maxmem <replaceable>nbbytes</replaceable></arg>
-	<arg>--nowarning</arg>
-	<arg>--noblanks</arg>
-	<arg>--nocdata</arg>
-	<arg>--format</arg>
-	<arg>--encode <replaceable>encoding</replaceable></arg>
-	<arg>--dropdtd</arg>
-	<arg>--nsclean</arg>
-	<arg>--testIO</arg>
-	<arg>--catalogs</arg>
-	<arg>--nocatalogs</arg>
-	<arg>--auto</arg>
-	<arg>--xinclude</arg>
-	<arg>--noxincludenode</arg>
-	<arg>--loaddtd</arg>
-	<arg>--dtdattr</arg>
-	<arg>--stream</arg>
-	<arg>--walker</arg>
-	<arg>--pattern <replaceable>patternvalue</replaceable></arg>
-	<arg>--chkregister</arg>
-	<arg>--relaxng</arg>
-	<arg>--schema</arg>
-	<arg>--c14n</arg>
+      <group choice="opt">
+        <arg choice="plain"><option>--version</option></arg>
+        <arg choice="plain"><option>--debug</option></arg>
+        <arg choice="plain"><option>--shell</option></arg>
+        <arg choice="plain"><option>--debugent</option></arg>
+        <arg choice="plain"><option>--copy</option></arg>
+        <arg choice="plain"><option>--recover</option></arg>
+        <arg choice="plain"><option>--noent</option></arg>
+        <arg choice="plain"><option>--noout</option></arg>
+        <arg choice="plain"><option>--nonet</option></arg>
+        <arg choice="plain"><option>--path "<replaceable class="option">PATHS</replaceable>"</option></arg>
+        <arg choice="plain"><option>--load-trace</option></arg>
+        <arg choice="plain"><option>--htmlout</option></arg>
+        <arg choice="plain"><option>--nowrap</option></arg>
+        <arg choice="plain"><option>--valid</option></arg>
+        <arg choice="plain"><option>--postvalid</option></arg>
+        <arg choice="plain"><option>--dtdvalid <replaceable class="option">URL</replaceable></option></arg>
+        <arg choice="plain"><option>--dtdvalidfpi <replaceable class="option">FPI</replaceable></option></arg>
+        <arg choice="plain"><option>--timing</option></arg>
+        <arg choice="plain"><option>--output <replaceable class="option">FILE</replaceable></option></arg>
+        <arg choice="plain"><option>--repeat</option></arg>
+        <arg choice="plain"><option>--insert</option></arg>
+        <arg choice="plain"><option>--compress</option></arg>
+        <arg choice="plain"><option>--html</option></arg>
+        <arg choice="plain"><option>--xmlout</option></arg>
+        <arg choice="plain"><option>--push</option></arg>
+        <arg choice="plain"><option>--memory</option></arg>
+        <arg choice="plain"><option>--maxmem <replaceable class="option">NBBYTES</replaceable></option></arg>
+        <arg choice="plain"><option>--nowarning</option></arg>
+        <arg choice="plain"><option>--noblanks</option></arg>
+        <arg choice="plain"><option>--nocdata</option></arg>
+        <arg choice="plain"><option>--format</option></arg>
+        <arg choice="plain"><option>--encode <replaceable class="option">ENCODING</replaceable></option></arg>
+        <arg choice="plain"><option>--dropdtd</option></arg>
+        <arg choice="plain"><option>--nsclean</option></arg>
+        <arg choice="plain"><option>--testIO</option></arg>
+        <arg choice="plain"><option>--catalogs</option></arg>
+        <arg choice="plain"><option>--nocatalogs</option></arg>
+        <arg choice="plain"><option>--auto</option></arg>
+        <arg choice="plain"><option>--xinclude</option></arg>
+        <arg choice="plain"><option>--noxincludenode</option></arg>
+        <arg choice="plain"><option>--loaddtd</option></arg>
+        <arg choice="plain"><option>--dtdattr</option></arg>
+        <arg choice="plain"><option>--stream</option></arg>
+        <arg choice="plain"><option>--walker</option></arg>
+        <arg choice="plain"><option>--pattern <replaceable class="option">PATTERNVALUE</replaceable></option></arg>
+        <arg choice="plain"><option>--chkregister</option></arg>
+        <arg choice="plain"><option>--relaxng <replaceable class="option">SCHEMA</replaceable></option></arg>
+        <arg choice="plain"><option>--schema <replaceable class="option">SCHEMA</replaceable></option></arg>
+        <arg choice="plain"><option>--c14n</option></arg>
       </group>
-      <arg><option><replaceable>xmlfile</replaceable></option></arg>
-  </cmdsynopsis>
+      <arg choice="req" rep="repeat"><replaceable>XML-FILE(S)</replaceable></arg>
+    </cmdsynopsis>
+    <cmdsynopsis>
+      <command>xmllint</command>
+      <arg choice="plain"><option>--help</option></arg>
+    </cmdsynopsis>
   </refsynopsisdiv>
 
   <refsect1 id="introduction">
-    <title>Introduction</title>
+    <title>DESCRIPTION</title>
     <para>
-      The xmllint program parses one or more XML files, specified on the
-      command line as <replaceable>xmlfile</replaceable> (or the standard
+      The &xmllint; program parses one or more XML files, specified on the
+      command line as <replaceable>XML-FILE</replaceable> (or the standard
       input if the filename provided is - ). It prints various
       types of output, depending upon the options selected. It is useful for
-      detecting errors both in <acronym>XML</acronym> code and in the
-      <acronym>XML</acronym> parser itself.
+      detecting errors both in <acronym>XML</acronym> code and in
+      the <acronym>XML</acronym> parser itself.
     </para>
 
     <para>
@@ -116,9 +122,16 @@
     </para>
   </refsect1>
   <refsect1 id="options">
-    <title>Options</title>
+    <title>OPTIONS</title>
     <variablelist>
       <varlistentry>
+	<term><option>--help</option></term>
+	<listitem>
+	  <simpara>Print out a a short usage summary for &xmllint;.</simpara>
+	</listitem>
+      </varlistentry>
+
+      <varlistentry>
 	<term><option>--version</option></term>
 	<listitem>
 	  <simpara>
@@ -182,7 +195,7 @@
 	<listitem>
 	  <simpara>
 	    Substitute entity values for entity
-	    references. By default, <application>xmllint</application> leaves entity
+	    references. By default, &xmllint; leaves entity
 	    references in place.
 	  </simpara>
 	</listitem>
@@ -210,8 +223,8 @@
 	<term><option>--noout</option></term>
 	<listitem>
 	  <simpara>
-	    Suppress output. By default,
-	    <application>xmllint</application> outputs the result tree.
+	    Suppress output. By default, &xmllint;
+	    outputs the result tree.
 	  </simpara>
 	</listitem>
       </varlistentry>
@@ -220,18 +233,18 @@
 	<term><option>--nonet</option></term>
 	<listitem>
 	  <simpara>
-	    Do not use the Internet to fetch DTD's or entities.
+	    Do not use the Internet to fetch <acronym>DTD</acronym>s or entities.
 	  </simpara>
 	</listitem>
       </varlistentry>
 
       <varlistentry>
-	<term> <option>--path</option> <replaceable>paths</replaceable></term>
+	<term> <option>--path</option> "<replaceable class="option">PATHS</replaceable>"</term>
 	<listitem>
 	  <simpara>
-	    Use the list (separated by space or column) of filesystem path
-	specified by <replaceable>paths</replaceable>  to load
-        <acronym>DTDs</acronym> or entities .
+	    Use the list (separated by space or colon) of filesystem path
+	specified by <replaceable>PATHS</replaceable>  to
+	load <acronym>DTD</acronym>s or entities .
 	  </simpara>
 	</listitem>
       </varlistentry>
@@ -250,7 +263,7 @@
 	<listitem>
 	  <simpara>
 	    Output results as an <acronym>HTML</acronym>
-	    file. This causes <application>xmllint</application> to output
+	    file. This causes &xmllint; to output
 	    the necessary <acronym>HTML</acronym> tags surrounding the result tree
 	    output so the results can be displayed in a browser. 
 	  </simpara>
@@ -261,20 +274,20 @@
 	<term><option>--nowrap </option></term>
 	<listitem>
 	  <simpara>
-	    Do not output HTML doc wrapper.
+	    Do not output <acronym>HTML</acronym> doc wrapper.
 	  </simpara>
 	</listitem>
       </varlistentry>
 
 <varlistentry>
-	<term><option>--valid </option></term>
+	<term><option>--valid</option></term>
 	<listitem>
 	  <simpara>
 	    Determine if the document is a valid instance
-	    of the included Document Type Definition (<acronym>DTD</acronym>). A
-	    <acronym>DTD</acronym> to be validated against also can be specified at
-	    the command line using the <option>--dtdvalid</option> option. By default,
-	    <application>xmllint</application> also checks to determine if the
+	    of the included Document Type Definition (<acronym>DTD</acronym>).
+	    A <acronym>DTD</acronym> to be validated against also can be specified at
+	    the command line using the <option>--dtdvalid</option> option. By
+	    default, &xmllint; also checks to determine if the
 	    document is well-formed.
 	  </simpara>
 	</listitem>
@@ -290,23 +303,23 @@
       </varlistentry>
    
     <varlistentry>
-	<term> <option>--dtdvalid</option> <replaceable>URL</replaceable></term>
+	<term> <option>--dtdvalid</option> <replaceable class="option">URL</replaceable></term>
 	<listitem>
 	  <simpara>
-	    Use the
-      <acronym>DTD</acronym> specified by <replaceable>URL</replaceable> for
+	    Use the <acronym>DTD</acronym>
+	    specified by <replaceable>URL</replaceable> for
       validation.
 	  </simpara>
 	</listitem>
       </varlistentry>
    
     <varlistentry>
-	<term> <option>--dtdvalidfpi</option> <replaceable>FPI</replaceable></term>
+	<term> <option>--dtdvalidfpi</option> <replaceable class="option">FPI</replaceable></term>
 	<listitem>
 	  <simpara>
-	    Use the
-      <acronym>DTD</acronym> specified by the Public Identifier
-      <replaceable>FPI</replaceable> for validation, note that this
+	    Use the <acronym>DTD</acronym>
+	    specified by the Public Identifier <replaceable>FPI</replaceable>
+	    for validation, note that this
       will require a Catalog exporting that Public Identifier to work.
 	  </simpara>
 	</listitem>
@@ -316,17 +329,18 @@
 	<term><option>--timing</option></term>
 	<listitem>
 	  <simpara>
-	    Output information about the time it takes
-	    <application>xmllint</application> to perform the various steps.
+	    Output information about the time it takes &xmllint;
+	    to perform the various steps.
 	  </simpara>
 	</listitem>
       </varlistentry>
       <varlistentry>
-	<term><option>--output</option> <replaceable>file</replaceable></term>
+	<term><option>--output</option> <replaceable class="option">FILE</replaceable></term>
 	<listitem>
 	  <simpara>Define a file path where xmllint will save the result of
 	  parsing. Usually the programs build a tree and save it on stdout, with
-	  this option the result XML instance will be saved onto a file.</simpara>
+	  this option the result <acronym>XML</acronym> instance will be saved onto
+	  a file.</simpara>
 	</listitem>
       </varlistentry>
    <varlistentry>
@@ -351,7 +365,7 @@
 	<term><option>--compress</option></term>
 	<listitem>
 	  <simpara>
-	    Turn on gzip compression of output.
+	    Turn on <application>gzip</application> compression of output.
 	  </simpara>
 	</listitem>
       </varlistentry>
@@ -368,9 +382,11 @@
 	<term><option>--xmlout</option></term>
 	<listitem>
 	  <simpara>Used in conjunction with <option>--html</option>. Usually
-  when HTML is parsed the document is saved with the HTML serializer, but with
-  this option the resulting document is saved with the XML serializer. This is
-  primarily used to generate XHTML from HTML input.</simpara>
+  when <acronym>HTML</acronym> is parsed the document is saved with
+  the <acronym>HTML</acronym> serializer, but with this option the resulting
+  document is saved with the <acronym>XML</acronym> serializer. This is
+  primarily used to generate <acronym>XHTML</acronym>
+  from <acronym>HTML</acronym> input.</simpara>
 	</listitem>
       </varlistentry>
     <varlistentry>
@@ -392,13 +408,13 @@
 	</listitem>
       </varlistentry>
       <varlistentry>
-	<term><option>--maxmem</option> <replaceable>nnbytes</replaceable></term>
+	<term><option>--maxmem</option> <replaceable class="option">NNBYTES</replaceable></term>
 	<listitem>
 	  <simpara>Test the parser memory
-  support. <replaceable>nnbytes</replaceable> is the maximum number of bytes the
+  support. <replaceable>NNBYTES</replaceable> is the maximum number of bytes the
   library is allowed to allocate. This can also be used to make sure batch
-  processing of XML files will not exhaust the virtual memory of the server
-  running them.</simpara>
+  processing of <acronym>XML</acronym> files will not exhaust the virtual memory
+  of the server running them.</simpara>
 	</listitem>
       </varlistentry>
     <varlistentry>
@@ -423,7 +439,7 @@
 	<term><option>--format</option></term>
 	<listitem>
 	  <simpara>
-	   Reformat and reindent the output. The $XMLLINT_INDENT
+	   Reformat and reindent the output. The <envar>XMLLINT_INDENT</envar>
 	   environment variable controls the indentation (default 
 	   value is two spaces &quot;  &quot;).
 	  </simpara>
@@ -440,7 +456,7 @@
       </varlistentry>
 
     <varlistentry>
-      <term><option>--encode</option> <replaceable>encoding</replaceable></term>
+      <term><option>--encode</option> <replaceable class="option">ENCODING</replaceable></term>
 	<listitem>
 	  <simpara>
 	   Output in the given encoding.
@@ -452,7 +468,8 @@
 	<term><option>--catalogs</option></term>
 	<listitem>
 	  <simpara>
-	   Use the catalogs from $SGML_CATALOG_FILES. Otherwise /etc/xml/catalog
+	   Use the catalogs from <envar>SGML_CATALOG_FILES</envar>.
+	   Otherwise <filename>/etc/xml/catalog</filename>
 	   is used by default.
 	  </simpara>
 	</listitem>
@@ -497,7 +514,7 @@
 	<term><option>--loaddtd</option></term>
 	<listitem>
 	  <simpara>
-	   Fetch external DTD.
+	   Fetch external <acronym>DTD</acronym>.
 	  </simpara>
 	</listitem>
       </varlistentry>
@@ -506,7 +523,8 @@
 	<term><option>--dtdattr</option></term>
 	<listitem>
 	  <simpara>
-	   Fetch external DTD and populate the tree with inherited attributes.
+	   Fetch external <acronym>DTD</acronym> and populate the tree with
+	   inherited attributes.
 	  </simpara>
 	</listitem>
       </varlistentry>
@@ -522,7 +540,8 @@
 	<term><option>--stream</option></term>
 	<listitem>
 	  <simpara>Use streaming API - useful when  used  in combination with
-              --relaxng or --valid options for validation of files that are
+      <option>--relaxng</option> or <option>--valid</option> options
+      for validation of files that are
 	    too large to be held in memory.</simpara> 
 	</listitem>
       </varlistentry>
@@ -530,19 +549,20 @@
 	<term><option>--walker</option></term>
 	<listitem>
 	  <simpara>Test the walker module, which is a reader interface but for a
-  document tree, instead of using the reader API on an unparsed document it
-  works on a existing in-memory tree. Used in debugging.</simpara> 
+    document tree, instead of using the reader <acronym>API</acronym> on an
+    unparsed document it works on a existing in-memory tree. Used in
+    debugging.</simpara> 
 	</listitem>
       </varlistentry>
       <varlistentry>
 	<term><option>--chkregister</option></term>
 	<listitem>
 	  <simpara>Turn on node registration. Useful for developers testing
-	  libxml2 node tracking code.</simpara>
+	  <application>libxml2</application> node tracking code.</simpara>
 	</listitem>
       </varlistentry>
       <varlistentry>
-	<term><option>--pattern</option> <replaceable>patternvalue</replaceable></term>
+	<term><option>--pattern</option> <replaceable class="option">PATTERNVALUE</replaceable></term>
 	<listitem>
 	  <simpara>Used to exercise the pattern recognition engine, which can be
 	  used with the reader interface to the parser. It allows to select some
@@ -551,16 +571,17 @@
 	</listitem>
       </varlistentry>
       <varlistentry>
-	<term><option>--relaxng</option> <replaceable>schema</replaceable></term>
+	<term><option>--relaxng</option> <replaceable class="option">SCHEMA</replaceable></term>
 	<listitem>
-	  <simpara>Use RelaxNG file named <replaceable>schema</replaceable> for
+	  <simpara>Use RelaxNG file named <replaceable class="option">SCHEMA</replaceable> for
 	  validation.</simpara>
 	</listitem>
       </varlistentry>
       <varlistentry>
-	<term><option>--schema</option> <replaceable>schema</replaceable></term>
+	<term><option>--schema</option> <replaceable>SCHEMA</replaceable></term>
 	<listitem>
-	  <simpara>Use a W3C XML Schema file named <replaceable>schema</replaceable> for validation.</simpara>
+	  <simpara>Use a W3C XML Schema file named <replaceable>SCHEMA</replaceable>
+	    for validation.</simpara>
 	</listitem>
       </varlistentry>
       <varlistentry>
@@ -576,15 +597,15 @@
   </refsect1>
 
   <refsect1 id="shell">
-    <title>Shell</title>
+    <title>SHELL COMMANDS</title>
     <para>
-      <application>xmllint</application> offers an interactive shell mode
+      &xmllint; offers an interactive shell mode
       invoked with the <option>--shell</option> command. Available commands in
       shell mode include:
     </para>
     <variablelist>
       <varlistentry>
-	<term><option>base</option></term>
+	<term><command>base</command></term>
 	<listitem>
 	  <simpara>
 	    display XML base of the node
@@ -592,7 +613,7 @@
 	</listitem>
       </varlistentry>
       <varlistentry>
-	<term><option>bye</option></term>
+	<term><command>bye</command></term>
 	<listitem>
 	  <simpara>
 	    leave shell
@@ -600,7 +621,7 @@
 	</listitem>
       </varlistentry>
       <varlistentry>
-	<term><option>cat <replaceable>node</replaceable></option></term>
+	<term><command>cat <replaceable>NODE</replaceable></command></term>
 	<listitem>
 	  <simpara>
 	    Display node if given or current node.
@@ -608,16 +629,16 @@
 	</listitem>
       </varlistentry>
       <varlistentry>
-	<term><option>cd <replaceable>path</replaceable></option></term>
+	<term><command>cd <replaceable>PATH</replaceable></command></term>
 	<listitem>
 	  <simpara>
-	    Change the current node to <replaceable>path</replaceable> (if given
+	    Change the current node to <replaceable>PATH</replaceable> (if given
 	    and unique) or root if no argument given.
 	  </simpara>
 	</listitem>
       </varlistentry>
       <varlistentry>
-	<term><option>dir <replaceable>path</replaceable></option></term>
+	<term><command>dir <replaceable>PATH</replaceable></command></term>
 	<listitem>
 	  <simpara>
 	    Dumps information about the node (namespace, attributes, content).
@@ -625,7 +646,7 @@
 	</listitem>
       </varlistentry>
       <varlistentry>
-	<term><option>du <replaceable>path</replaceable></option></term>
+	<term><command>du <replaceable>PATH</replaceable></command></term>
 	<listitem>
 	  <simpara>
 	    Show the structure of the subtree under path or the current node.
@@ -633,7 +654,7 @@
 	</listitem>
       </varlistentry>
       <varlistentry>
-	<term><option>exit</option></term>
+	<term><command>exit</command></term>
 	<listitem>
 	  <simpara>
 	    Leave the shell.
@@ -641,7 +662,7 @@
 	</listitem>
       </varlistentry>
       <varlistentry>
-	<term><option>help</option></term>
+	<term><command>help</command></term>
 	<listitem>
 	  <simpara>
 	    Show this help.
@@ -649,7 +670,7 @@
 	</listitem>
       </varlistentry>
       <varlistentry>
-	<term><option>free</option></term>
+	<term><command>free</command></term>
 	<listitem>
 	  <simpara>
 	    Display memory usage.
@@ -657,7 +678,7 @@
 	</listitem>
       </varlistentry>
       <varlistentry>
-	<term><option>load <replaceable>name</replaceable></option></term>
+	<term><command>load <replaceable>FILENAME</replaceable></command></term>
 	<listitem>
 	  <simpara>
 	    Load a new document with the given name.
@@ -665,16 +686,16 @@
 	</listitem>
       </varlistentry>
       <varlistentry>
-	<term><option>ls <replaceable>path</replaceable></option></term>
+	<term><command>ls <replaceable>PATH</replaceable></command></term>
 	<listitem>
 	  <simpara>
-	    List contents of <replaceable>path</replaceable> (if given) or the
+	    List contents of <replaceable>PATH</replaceable> (if given) or the
 	    current directory.
 	  </simpara>
 	</listitem>
       </varlistentry>
       <varlistentry>
-	<term><option>pwd</option></term>
+	<term><command>pwd</command></term>
 	<listitem>
 	  <simpara>
 	    Display the path to the current node.
@@ -682,7 +703,7 @@
 	</listitem>
       </varlistentry>
       <varlistentry>
-	<term><option>quit</option></term>
+	<term><command>quit</command></term>
 	<listitem>
 	  <simpara>
 	    Leave the shell.
@@ -690,10 +711,10 @@
 	</listitem>
       </varlistentry>
       <varlistentry>
-	<term><option>save <replaceable>name</replaceable></option></term>
+	<term><command>save <replaceable>FILENAME</replaceable></command></term>
 	<listitem>
 	  <simpara>
-	    Saves the current document to <replaceable>name</replaceable> if
+	    Saves the current document to <replaceable>FILENAME</replaceable> if
 	    given or to the original name.
 	  </simpara>
 	</listitem>
@@ -707,7 +728,7 @@
 	</listitem>
       </varlistentry>
       <varlistentry>
-	<term><option>write <replaceable>name</replaceable></option></term>
+	<term><command>write <replaceable>FILENAME</replaceable></command></term>
 	<listitem>
 	  <simpara>
 	    Write the current node to the given filename.
@@ -717,86 +738,109 @@
      
     </variablelist>
   </refsect1>
-<refsect1>
-   <title>Catalogs</title>
-     <para>Catalog behavior can be changed by redirecting
-     queries to the user's own set of catalogs. This can be done by setting the
-     <varname>XML_CATALOG_FILES</varname> environment variable to a list of
-     catalogs. An empty one should deactivate loading the default
-      <filename>/etc/xml/catalog</filename> default catalog.</para>
-  </refsect1>
   <refsect1>
-    <title>Debugging Catalogs</title>
-    <para>Setting the environment variable <varname>XML_DEBUG_CATALOG</varname>
-    using the command <command>&quot;export XML_DEBUG_CATALOG=&quot;</command>
-    outputs debugging information related to catalog operations.</para>
-  </refsect1>
-  <refsect1>
-    <title>Error Return Codes</title>
-    <para>On the completion of execution, <application>Xmllint</application>
+    <title>ENVIRONMENT</title>
+    <para>On the completion of execution, &xmllint;
     returns the following error codes:</para>
     <variablelist>
       <varlistentry>
-	<term>0</term>
+	<term><envar>SGML_CATALOG_FILES</envar></term>
 	<listitem>
-	  <simpara>No error</simpara>
+	  <simpara>...</simpara>
 	</listitem>
       </varlistentry>
       <varlistentry>
-	<term>1</term>
+	<term><envar>XML_CATALOG_FILES</envar></term>
 	<listitem>
-	  <simpara>Unclassified</simpara>
+	  <simpara>Catalog behavior can be changed by redirecting
+     queries to the user's own set of catalogs. This can be done by setting
+     the <envar>XML_CATALOG_FILES</envar> environment variable to a list of
+     catalogs. An empty one should deactivate loading the
+     default <filename>/etc/xml/catalog</filename> default catalog.</simpara>
 	</listitem>
       </varlistentry>
       <varlistentry>
-	<term>2</term>
+	<term><envar>XML_DEBUG_CATALOG</envar></term>
 	<listitem>
-	  <simpara>Error in DTD</simpara>
+	  <simpara>Setting the environment variable <envar>XML_DEBUG_CATALOG</envar>
+    using the command <command>&quot;export XML_DEBUG_CATALOG=&quot;</command>
+    outputs debugging information related to catalog operations.</simpara>
 	</listitem>
       </varlistentry>
       <varlistentry>
-	<term>3</term>
+	<term><envar>XMLLINT_INDENT</envar></term>
 	<listitem>
-	  <simpara>Validation error</simpara>
+	  <simpara>...</simpara>
 	</listitem>
       </varlistentry>
+    </variablelist>
+  </refsect1>
+  <refsect1>
+    <title>DIAGNOSTICS</title>
+    <para>On the completion of execution, &xmllint;
+    returns the following error codes:</para>
+    <variablelist>
       <varlistentry>
-	<term>4</term>
-	<listitem>
-	  <simpara>Validation error</simpara>
-	</listitem>
+        <term><errorcode>0</errorcode></term>
+        <listitem>
+          <simpara>No error</simpara>
+        </listitem>
       </varlistentry>
       <varlistentry>
-	<term>5</term>
-	<listitem>
-	  <simpara>Error in schema compilation</simpara>
-	</listitem>
+        <term><errorcode>1</errorcode></term>
+        <listitem>
+          <simpara>Unclassified</simpara>
+        </listitem>
       </varlistentry>
       <varlistentry>
-	<term>6</term>
-	<listitem>
-	  <simpara>Error writing output</simpara>
-	</listitem>
+        <term><errorcode>2</errorcode></term>
+        <listitem>
+          <simpara>Error in <acronym>DTD</acronym></simpara>
+        </listitem>
       </varlistentry>
       <varlistentry>
-	<term>7</term>
-	<listitem>
-	  <simpara>Error in pattern (generated when
-	  <optional>--pattern</optional> option is used)</simpara>
-	</listitem>
+        <term><errorcode>3</errorcode></term>
+        <listitem>
+          <simpara>Validation error</simpara>
+        </listitem>
       </varlistentry>
       <varlistentry>
-	<term>8</term>
-	<listitem>
-	  <simpara>Error in Reader registration (generated when
-	  <optional>--chkregister</optional> option is used)</simpara>
-	</listitem>
+        <term><errorcode>4</errorcode></term>
+        <listitem>
+          <simpara>Validation error</simpara>
+        </listitem>
       </varlistentry>
       <varlistentry>
-	<term>9</term>
-	<listitem>
-	  <simpara>Out of memory error</simpara>
-	</listitem>
+        <term><errorcode>5</errorcode></term>
+        <listitem>
+          <simpara>Error in schema compilation</simpara>
+        </listitem>
+      </varlistentry>
+      <varlistentry>
+        <term><errorcode>6</errorcode></term>
+        <listitem>
+          <simpara>Error writing output</simpara>
+        </listitem>
+      </varlistentry>
+      <varlistentry>
+        <term><errorcode>7</errorcode></term>
+        <listitem>
+          <simpara>Error in pattern (generated when <option>--pattern</option>
+     	    option is used)</simpara>
+     	  </listitem>
+      </varlistentry>
+      <varlistentry>
+        <term><errorcode>8</errorcode></term>
+        <listitem>
+          <simpara>Error in Reader registration (generated
+          when <option>--chkregister</option> option is used)</simpara>
+        </listitem>
+      </varlistentry>
+      <varlistentry>
+        <term><errorcode>9</errorcode></term>
+          <listitem>
+            <simpara>Out of memory error</simpara>
+          </listitem>
       </varlistentry>
     </variablelist>
   </refsect1>