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| 10 | </style><title>Catalog support</title></head><body bgcolor="#8b7765" text="#000000" link="#a06060" vlink="#000000"><table border="0" width="100%" cellpadding="5" cellspacing="0" align="center"><tr><td width="120"><a href="http://swpat.ffii.org/"><img src="epatents.png" alt="Action against software patents" /></a></td><td width="180"><a href="http://www.gnome.org/"><img src="gnome2.png" alt="Gnome2 Logo" /></a><a href="http://www.w3.org/Status"><img src="w3c.png" alt="W3C Logo" /></a><a href="http://www.redhat.com/"><img src="redhat.gif" alt="Red Hat Logo" /></a><div align="left"><a href="http://xmlsoft.org/"><img src="Libxml2-Logo-180x168.gif" alt="Made with Libxml2 Logo" /></a></div></td><td><table border="0" width="90%" cellpadding="2" cellspacing="0" align="center" bgcolor="#000000"><tr><td><table width="100%" border="0" cellspacing="1" cellpadding="3" bgcolor="#fffacd"><tr><td align="center"><h1>The XML C parser and toolkit of Gnome</h1><h2>Catalog support</h2></td></tr></table></td></tr></table></td></tr></table><table border="0" cellpadding="4" cellspacing="0" width="100%" align="center"><tr><td bgcolor="#8b7765"><table border="0" cellspacing="0" cellpadding="2" width="100%"><tr><td valign="top" width="200" bgcolor="#8b7765"><table border="0" cellspacing="0" cellpadding="1" width="100%" bgcolor="#000000"><tr><td><table width="100%" border="0" cellspacing="1" cellpadding="3"><tr><td colspan="1" bgcolor="#eecfa1" align="center"><center><b>Main Menu</b></center></td></tr><tr><td bgcolor="#fffacd"><form action="search.php" enctype="application/x-www-form-urlencoded" method="get"><input name="query" type="text" size="20" value="" /><input name="submit" type="submit" value="Search ..." /></form><ul><li><a href="index.html">Home</a></li><li><a href="html/index.html">Reference Manual</a></li><li><a href="intro.html">Introduction</a></li><li><a href="FAQ.html">FAQ</a></li><li><a href="docs.html" style="font-weight:bold">Developer Menu</a></li><li><a href="bugs.html">Reporting bugs and getting help</a></li><li><a href="help.html">How to help</a></li><li><a href="downloads.html">Downloads</a></li><li><a href="news.html">Releases</a></li><li><a href="XMLinfo.html">XML</a></li><li><a href="XSLT.html">XSLT</a></li><li><a href="xmldtd.html">Validation & DTDs</a></li><li><a href="encoding.html">Encodings support</a></li><li><a href="catalog.html">Catalog support</a></li><li><a href="namespaces.html">Namespaces</a></li><li><a href="contribs.html">Contributions</a></li><li><a href="examples/index.html" style="font-weight:bold">Code Examples</a></li><li><a href="html/index.html" style="font-weight:bold">API Menu</a></li><li><a href="guidelines.html">XML Guidelines</a></li><li><a href="ChangeLog.html">Recent Changes</a></li></ul></td></tr></table><table width="100%" border="0" cellspacing="1" cellpadding="3"><tr><td colspan="1" bgcolor="#eecfa1" align="center"><center><b>Related links</b></center></td></tr><tr><td bgcolor="#fffacd"><ul><li><a href="http://mail.gnome.org/archives/xml/">Mail archive</a></li><li><a href="http://xmlsoft.org/XSLT/">XSLT libxslt</a></li><li><a href="http://phd.cs.unibo.it/gdome2/">DOM gdome2</a></li><li><a href="http://www.aleksey.com/xmlsec/">XML-DSig xmlsec</a></li><li><a href="ftp://xmlsoft.org/">FTP</a></li><li><a href="http://www.zlatkovic.com/projects/libxml/">Windows binaries</a></li><li><a href="http://opencsw.org/packages/libxml2">Solaris binaries</a></li><li><a href="http://www.explain.com.au/oss/libxml2xslt.html">MacOsX binaries</a></li><li><a href="http://lxml.de/">lxml Python bindings</a></li><li><a href="http://cpan.uwinnipeg.ca/dist/XML-LibXML">Perl bindings</a></li><li><a href="http://libxmlplusplus.sourceforge.net/">C++ bindings</a></li><li><a href="http://www.zend.com/php5/articles/php5-xmlphp.php#Heading4">PHP bindings</a></li><li><a href="http://sourceforge.net/projects/libxml2-pas/">Pascal bindings</a></li><li><a href="http://libxml.rubyforge.org/">Ruby bindings</a></li><li><a href="http://tclxml.sourceforge.net/">Tcl bindings</a></li><li><a href="http://bugzilla.gnome.org/buglist.cgi?product=libxml2">Bug Tracker</a></li></ul></td></tr></table></td></tr></table></td><td valign="top" bgcolor="#8b7765"><table border="0" cellspacing="0" cellpadding="1" width="100%"><tr><td><table border="0" cellspacing="0" cellpadding="1" width="100%" bgcolor="#000000"><tr><td><table border="0" cellpadding="3" cellspacing="1" width="100%"><tr><td bgcolor="#fffacd"><p>Table of Content:</p><ol>
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| 11 | <li><a href="General2">General overview</a></li>
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| 12 | <li><a href="#definition">The definition</a></li>
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| 13 | <li><a href="#Simple">Using catalogs</a></li>
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| 14 | <li><a href="#Some">Some examples</a></li>
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| 15 | <li><a href="#reference">How to tune catalog usage</a></li>
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| 16 | <li><a href="#validate">How to debug catalog processing</a></li>
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| 17 | <li><a href="#Declaring">How to create and maintain catalogs</a></li>
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| 18 | <li><a href="#implemento">The implementor corner quick review of the
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| 19 | API</a></li>
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| 20 | <li><a href="#Other">Other resources</a></li>
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| 21 | </ol><h3><a name="General2" id="General2">General overview</a></h3><p>What is a catalog? Basically it's a lookup mechanism used when an entity
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| 22 | (a file or a remote resource) references another entity. The catalog lookup
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| 23 | is inserted between the moment the reference is recognized by the software
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| 24 | (XML parser, stylesheet processing, or even images referenced for inclusion
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| 25 | in a rendering) and the time where loading that resource is actually
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| 26 | started.</p><p>It is basically used for 3 things:</p><ul>
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| 27 | <li>mapping from "logical" names, the public identifiers and a more
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| 28 | concrete name usable for download (and URI). For example it can associate
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| 29 | the logical name
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| 30 | <p>"-//OASIS//DTD DocBook XML V4.1.2//EN"</p>
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| 31 | <p>of the DocBook 4.1.2 XML DTD with the actual URL where it can be
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| 32 | downloaded</p>
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| 33 | <p>http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd</p>
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| 34 | </li>
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| 35 | <li>remapping from a given URL to another one, like an HTTP indirection
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| 36 | saying that
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| 37 | <p>"http://www.oasis-open.org/committes/tr.xsl"</p>
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| 38 | <p>should really be looked at</p>
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| 39 | <p>"http://www.oasis-open.org/committes/entity/stylesheets/base/tr.xsl"</p>
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| 40 | </li>
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| 41 | <li>providing a local cache mechanism allowing to load the entities
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| 42 | associated to public identifiers or remote resources, this is a really
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| 43 | important feature for any significant deployment of XML or SGML since it
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| 44 | allows to avoid the aleas and delays associated to fetching remote
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| 45 | resources.</li>
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| 46 | </ul><h3><a name="definition" id="definition">The definitions</a></h3><p>Libxml, as of 2.4.3 implements 2 kind of catalogs:</p><ul>
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| 47 | <li>the older SGML catalogs, the official spec is SGML Open Technical
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| 48 | Resolution TR9401:1997, but is better understood by reading <a href="http://www.jclark.com/sp/catalog.htm">the SP Catalog page</a> from
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| 49 | James Clark. This is relatively old and not the preferred mode of
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| 50 | operation of libxml.</li>
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| 51 | <li><a href="http://www.oasis-open.org/committees/entity/spec.html">XML
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| 52 | Catalogs</a> is far more flexible, more recent, uses an XML syntax and
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| 53 | should scale quite better. This is the default option of libxml.</li>
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| 54 | </ul><p></p><h3><a name="Simple" id="Simple">Using catalog</a></h3><p>In a normal environment libxml2 will by default check the presence of a
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| 55 | catalog in /etc/xml/catalog, and assuming it has been correctly populated,
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| 56 | the processing is completely transparent to the document user. To take a
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| 57 | concrete example, suppose you are authoring a DocBook document, this one
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| 58 | starts with the following DOCTYPE definition:</p><pre><?xml version='1.0'?>
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| 59 | <!DOCTYPE book PUBLIC "-//Norman Walsh//DTD DocBk XML V3.1.4//EN"
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| 60 | "http://nwalsh.com/docbook/xml/3.1.4/db3xml.dtd"></pre><p>When validating the document with libxml, the catalog will be
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| 61 | automatically consulted to lookup the public identifier "-//Norman Walsh//DTD
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| 62 | DocBk XML V3.1.4//EN" and the system identifier
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| 63 | "http://nwalsh.com/docbook/xml/3.1.4/db3xml.dtd", and if these entities have
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| 64 | been installed on your system and the catalogs actually point to them, libxml
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| 65 | will fetch them from the local disk.</p><p style="font-size: 10pt"><strong>Note</strong>: Really don't use this
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| 66 | DOCTYPE example it's a really old version, but is fine as an example.</p><p>Libxml2 will check the catalog each time that it is requested to load an
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| 67 | entity, this includes DTD, external parsed entities, stylesheets, etc ... If
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| 68 | your system is correctly configured all the authoring phase and processing
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| 69 | should use only local files, even if your document stays portable because it
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| 70 | uses the canonical public and system ID, referencing the remote document.</p><h3><a name="Some" id="Some">Some examples:</a></h3><p>Here is a couple of fragments from XML Catalogs used in libxml2 early
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| 71 | regression tests in <code>test/catalogs</code> :</p><pre><?xml version="1.0"?>
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| 72 | <!DOCTYPE catalog PUBLIC
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| 73 | "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
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| 74 | "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd">
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| 75 | <catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog">
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| 76 | <public publicId="-//OASIS//DTD DocBook XML V4.1.2//EN"
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| 77 | uri="http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"/>
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| 78 | ...</pre><p>This is the beginning of a catalog for DocBook 4.1.2, XML Catalogs are
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| 79 | written in XML, there is a specific namespace for catalog elements
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| 80 | "urn:oasis:names:tc:entity:xmlns:xml:catalog". The first entry in this
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| 81 | catalog is a <code>public</code> mapping it allows to associate a Public
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| 82 | Identifier with an URI.</p><pre>...
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| 83 | <rewriteSystem systemIdStartString="http://www.oasis-open.org/docbook/"
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| 84 | rewritePrefix="file:///usr/share/xml/docbook/"/>
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| 85 | ...</pre><p>A <code>rewriteSystem</code> is a very powerful instruction, it says that
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| 86 | any URI starting with a given prefix should be looked at another URI
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| 87 | constructed by replacing the prefix with an new one. In effect this acts like
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| 88 | a cache system for a full area of the Web. In practice it is extremely useful
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| 89 | with a file prefix if you have installed a copy of those resources on your
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| 90 | local system.</p><pre>...
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| 91 | <delegatePublic publicIdStartString="-//OASIS//DTD XML Catalog //"
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| 92 | catalog="file:///usr/share/xml/docbook.xml"/>
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| 93 | <delegatePublic publicIdStartString="-//OASIS//ENTITIES DocBook XML"
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| 94 | catalog="file:///usr/share/xml/docbook.xml"/>
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| 95 | <delegatePublic publicIdStartString="-//OASIS//DTD DocBook XML"
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| 96 | catalog="file:///usr/share/xml/docbook.xml"/>
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| 97 | <delegateSystem systemIdStartString="http://www.oasis-open.org/docbook/"
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| 98 | catalog="file:///usr/share/xml/docbook.xml"/>
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| 99 | <delegateURI uriStartString="http://www.oasis-open.org/docbook/"
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| 100 | catalog="file:///usr/share/xml/docbook.xml"/>
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| 101 | ...</pre><p>Delegation is the core features which allows to build a tree of catalogs,
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| 102 | easier to maintain than a single catalog, based on Public Identifier, System
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| 103 | Identifier or URI prefixes it instructs the catalog software to look up
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| 104 | entries in another resource. This feature allow to build hierarchies of
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| 105 | catalogs, the set of entries presented should be sufficient to redirect the
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| 106 | resolution of all DocBook references to the specific catalog in
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| 107 | <code>/usr/share/xml/docbook.xml</code> this one in turn could delegate all
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| 108 | references for DocBook 4.2.1 to a specific catalog installed at the same time
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| 109 | as the DocBook resources on the local machine.</p><h3><a name="reference" id="reference">How to tune catalog usage:</a></h3><p>The user can change the default catalog behaviour by redirecting queries
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| 110 | to its own set of catalogs, this can be done by setting the
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| 111 | <code>XML_CATALOG_FILES</code> environment variable to a list of catalogs, an
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| 112 | empty one should deactivate loading the default <code>/etc/xml/catalog</code>
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| 113 | default catalog</p><h3><a name="validate" id="validate">How to debug catalog processing:</a></h3><p>Setting up the <code>XML_DEBUG_CATALOG</code> environment variable will
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| 114 | make libxml2 output debugging information for each catalog operations, for
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| 115 | example:</p><pre>orchis:~/XML -> xmllint --memory --noout test/ent2
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| 116 | warning: failed to load external entity "title.xml"
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| 117 | orchis:~/XML -> export XML_DEBUG_CATALOG=
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| 118 | orchis:~/XML -> xmllint --memory --noout test/ent2
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| 119 | Failed to parse catalog /etc/xml/catalog
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| 120 | Failed to parse catalog /etc/xml/catalog
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| 121 | warning: failed to load external entity "title.xml"
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| 122 | Catalogs cleanup
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| 123 | orchis:~/XML -> </pre><p>The test/ent2 references an entity, running the parser from memory makes
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| 124 | the base URI unavailable and the the "title.xml" entity cannot be loaded.
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| 125 | Setting up the debug environment variable allows to detect that an attempt is
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| 126 | made to load the <code>/etc/xml/catalog</code> but since it's not present the
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| 127 | resolution fails.</p><p>But the most advanced way to debug XML catalog processing is to use the
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| 128 | <strong>xmlcatalog</strong> command shipped with libxml2, it allows to load
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| 129 | catalogs and make resolution queries to see what is going on. This is also
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| 130 | used for the regression tests:</p><pre>orchis:~/XML -> ./xmlcatalog test/catalogs/docbook.xml \
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| 131 | "-//OASIS//DTD DocBook XML V4.1.2//EN"
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| 132 | http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd
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| 133 | orchis:~/XML -> </pre><p>For debugging what is going on, adding one -v flags increase the verbosity
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| 134 | level to indicate the processing done (adding a second flag also indicate
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| 135 | what elements are recognized at parsing):</p><pre>orchis:~/XML -> ./xmlcatalog -v test/catalogs/docbook.xml \
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| 136 | "-//OASIS//DTD DocBook XML V4.1.2//EN"
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| 137 | Parsing catalog test/catalogs/docbook.xml's content
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| 138 | Found public match -//OASIS//DTD DocBook XML V4.1.2//EN
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| 139 | http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd
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| 140 | Catalogs cleanup
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| 141 | orchis:~/XML -> </pre><p>A shell interface is also available to debug and process multiple queries
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| 142 | (and for regression tests):</p><pre>orchis:~/XML -> ./xmlcatalog -shell test/catalogs/docbook.xml \
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| 143 | "-//OASIS//DTD DocBook XML V4.1.2//EN"
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| 144 | > help
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| 145 | Commands available:
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| 146 | public PublicID: make a PUBLIC identifier lookup
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| 147 | system SystemID: make a SYSTEM identifier lookup
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| 148 | resolve PublicID SystemID: do a full resolver lookup
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| 149 | add 'type' 'orig' 'replace' : add an entry
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| 150 | del 'values' : remove values
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| 151 | dump: print the current catalog state
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| 152 | debug: increase the verbosity level
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| 153 | quiet: decrease the verbosity level
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| 154 | exit: quit the shell
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| 155 | > public "-//OASIS//DTD DocBook XML V4.1.2//EN"
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| 156 | http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd
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| 157 | > quit
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| 158 | orchis:~/XML -> </pre><p>This should be sufficient for most debugging purpose, this was actually
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| 159 | used heavily to debug the XML Catalog implementation itself.</p><h3><a name="Declaring" id="Declaring">How to create and maintain</a> catalogs:</h3><p>Basically XML Catalogs are XML files, you can either use XML tools to
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| 160 | manage them or use <strong>xmlcatalog</strong> for this. The basic step is
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| 161 | to create a catalog the -create option provide this facility:</p><pre>orchis:~/XML -> ./xmlcatalog --create tst.xml
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| 162 | <?xml version="1.0"?>
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| 163 | <!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
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| 164 | "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd">
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| 165 | <catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"/>
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| 166 | orchis:~/XML -> </pre><p>By default xmlcatalog does not overwrite the original catalog and save the
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| 167 | result on the standard output, this can be overridden using the -noout
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| 168 | option. The <code>-add</code> command allows to add entries in the
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| 169 | catalog:</p><pre>orchis:~/XML -> ./xmlcatalog --noout --create --add "public" \
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| 170 | "-//OASIS//DTD DocBook XML V4.1.2//EN" \
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| 171 | http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd tst.xml
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| 172 | orchis:~/XML -> cat tst.xml
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| 173 | <?xml version="1.0"?>
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| 174 | <!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN" \
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| 175 | "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd">
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| 176 | <catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog">
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| 177 | <public publicId="-//OASIS//DTD DocBook XML V4.1.2//EN"
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| 178 | uri="http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"/>
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| 179 | </catalog>
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| 180 | orchis:~/XML -> </pre><p>The <code>-add</code> option will always take 3 parameters even if some of
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| 181 | the XML Catalog constructs (like nextCatalog) will have only a single
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| 182 | argument, just pass a third empty string, it will be ignored.</p><p>Similarly the <code>-del</code> option remove matching entries from the
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| 183 | catalog:</p><pre>orchis:~/XML -> ./xmlcatalog --del \
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| 184 | "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" tst.xml
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| 185 | <?xml version="1.0"?>
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| 186 | <!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
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| 187 | "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd">
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| 188 | <catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"/>
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| 189 | orchis:~/XML -> </pre><p>The catalog is now empty. Note that the matching of <code>-del</code> is
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| 190 | exact and would have worked in a similar fashion with the Public ID
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| 191 | string.</p><p>This is rudimentary but should be sufficient to manage a not too complex
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| 192 | catalog tree of resources.</p><h3><a name="implemento" id="implemento">The implementor corner quick review of the
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| 193 | API:</a></h3><p>First, and like for every other module of libxml, there is an
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| 194 | automatically generated <a href="html/libxml-catalog.html">API page for
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| 195 | catalog support</a>.</p><p>The header for the catalog interfaces should be included as:</p><pre>#include <libxml/catalog.h></pre><p>The API is voluntarily kept very simple. First it is not obvious that
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| 196 | applications really need access to it since it is the default behaviour of
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| 197 | libxml2 (Note: it is possible to completely override libxml2 default catalog
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| 198 | by using <a href="html/libxml-parser.html">xmlSetExternalEntityLoader</a> to
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| 199 | plug an application specific resolver).</p><p>Basically libxml2 support 2 catalog lists:</p><ul>
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| 200 | <li>the default one, global shared by all the application</li>
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| 201 | <li>a per-document catalog, this one is built if the document uses the
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| 202 | <code>oasis-xml-catalog</code> PIs to specify its own catalog list, it is
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| 203 | associated to the parser context and destroyed when the parsing context
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| 204 | is destroyed.</li>
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| 205 | </ul><p>the document one will be used first if it exists.</p><h4>Initialization routines:</h4><p>xmlInitializeCatalog(), xmlLoadCatalog() and xmlLoadCatalogs() should be
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| 206 | used at startup to initialize the catalog, if the catalog should be
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| 207 | initialized with specific values xmlLoadCatalog() or xmlLoadCatalogs()
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| 208 | should be called before xmlInitializeCatalog() which would otherwise do a
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| 209 | default initialization first.</p><p>The xmlCatalogAddLocal() call is used by the parser to grow the document
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| 210 | own catalog list if needed.</p><h4>Preferences setup:</h4><p>The XML Catalog spec requires the possibility to select default
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| 211 | preferences between public and system delegation,
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| 212 | xmlCatalogSetDefaultPrefer() allows this, xmlCatalogSetDefaults() and
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| 213 | xmlCatalogGetDefaults() allow to control if XML Catalogs resolution should
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| 214 | be forbidden, allowed for global catalog, for document catalog or both, the
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| 215 | default is to allow both.</p><p>And of course xmlCatalogSetDebug() allows to generate debug messages
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| 216 | (through the xmlGenericError() mechanism).</p><h4>Querying routines:</h4><p>xmlCatalogResolve(), xmlCatalogResolveSystem(), xmlCatalogResolvePublic()
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| 217 | and xmlCatalogResolveURI() are relatively explicit if you read the XML
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| 218 | Catalog specification they correspond to section 7 algorithms, they should
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| 219 | also work if you have loaded an SGML catalog with a simplified semantic.</p><p>xmlCatalogLocalResolve() and xmlCatalogLocalResolveURI() are the same but
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| 220 | operate on the document catalog list</p><h4>Cleanup and Miscellaneous:</h4><p>xmlCatalogCleanup() free-up the global catalog, xmlCatalogFreeLocal() is
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| 221 | the per-document equivalent.</p><p>xmlCatalogAdd() and xmlCatalogRemove() are used to dynamically modify the
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| 222 | first catalog in the global list, and xmlCatalogDump() allows to dump a
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| 223 | catalog state, those routines are primarily designed for xmlcatalog, I'm not
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| 224 | sure that exposing more complex interfaces (like navigation ones) would be
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| 225 | really useful.</p><p>The xmlParseCatalogFile() is a function used to load XML Catalog files,
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| 226 | it's similar as xmlParseFile() except it bypass all catalog lookups, it's
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| 227 | provided because this functionality may be useful for client tools.</p><h4>threaded environments:</h4><p>Since the catalog tree is built progressively, some care has been taken to
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| 228 | try to avoid troubles in multithreaded environments. The code is now thread
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| 229 | safe assuming that the libxml2 library has been compiled with threads
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| 230 | support.</p><p></p><h3><a name="Other" id="Other">Other resources</a></h3><p>The XML Catalog specification is relatively recent so there isn't much
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| 231 | literature to point at:</p><ul>
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| 232 | <li>You can find a good rant from Norm Walsh about <a href="http://www.arbortext.com/Think_Tank/XML_Resources/Issue_Three/issue_three.html">the
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| 233 | need for catalogs</a>, it provides a lot of context information even if
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| 234 | I don't agree with everything presented. Norm also wrote a more recent
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| 235 | article <a href="http://wwws.sun.com/software/xml/developers/resolver/article/">XML
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| 236 | entities and URI resolvers</a> describing them.</li>
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| 237 | <li>An <a href="http://home.ccil.org/~cowan/XML/XCatalog.html">old XML
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| 238 | catalog proposal</a> from John Cowan</li>
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| 239 | <li>The <a href="http://www.rddl.org/">Resource Directory Description
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| 240 | Language</a> (RDDL) another catalog system but more oriented toward
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| 241 | providing metadata for XML namespaces.</li>
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| 242 | <li>the page from the OASIS Technical <a href="http://www.oasis-open.org/committees/entity/">Committee on Entity
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| 243 | Resolution</a> who maintains XML Catalog, you will find pointers to the
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| 244 | specification update, some background and pointers to others tools
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| 245 | providing XML Catalog support</li>
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| 246 | <li>There is a <a href="buildDocBookCatalog">shell script</a> to generate
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| 247 | XML Catalogs for DocBook 4.1.2 . If it can write to the /etc/xml/
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| 248 | directory, it will set-up /etc/xml/catalog and /etc/xml/docbook based on
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| 249 | the resources found on the system. Otherwise it will just create
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| 250 | ~/xmlcatalog and ~/dbkxmlcatalog and doing:
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| 251 | <p><code>export XML_CATALOG_FILES=$HOME/xmlcatalog</code></p>
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| 252 | <p>should allow to process DocBook documentations without requiring
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| 253 | network accesses for the DTD or stylesheets</p>
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| 254 | </li>
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| 255 | <li>I have uploaded <a href="ftp://xmlsoft.org/libxml2/test/dbk412catalog.tar.gz">a
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| 256 | small tarball</a> containing XML Catalogs for DocBook 4.1.2 which seems
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| 257 | to work fine for me too</li>
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| 258 | <li>The <a href="http://www.xmlsoft.org/xmlcatalog_man.html">xmlcatalog
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| 259 | manual page</a></li>
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| 260 | </ul><p>If you have suggestions for corrections or additions, simply contact
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| 261 | me:</p><p><a href="bugs.html">Daniel Veillard</a></p></td></tr></table></td></tr></table></td></tr></table></td></tr></table></td></tr></table></body></html>
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