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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 &amp; 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>
 11    <li><a href="General2">General overview</a></li>
 12    <li><a href="#definition">The definition</a></li>
 13    <li><a href="#Simple">Using catalogs</a></li>
 14    <li><a href="#Some">Some examples</a></li>
 15    <li><a href="#reference">How to tune  catalog usage</a></li>
 16    <li><a href="#validate">How to debug catalog processing</a></li>
 17    <li><a href="#Declaring">How to create and maintain catalogs</a></li>
 18    <li><a href="#implemento">The implementor corner quick review of the
 19    API</a></li>
 20    <li><a href="#Other">Other resources</a></li>
 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
 22  (a file or a remote resource) references another entity. The catalog lookup
 23  is inserted between the moment the reference is recognized by the software
 24  (XML parser, stylesheet processing, or even images referenced for inclusion
 25  in a rendering) and the time where loading that resource is actually
 26  started.</p><p>It is basically used for 3 things:</p><ul>
 27    <li>mapping from "logical" names, the public identifiers and a more
 28      concrete name usable for download (and URI). For example it can associate
 29      the logical name
 30      <p>"-//OASIS//DTD DocBook XML V4.1.2//EN"</p>
 31      <p>of the DocBook 4.1.2 XML DTD with the actual URL where it can be
 32      downloaded</p>
 33      <p>http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd</p>
 34    </li>
 35    <li>remapping from a given URL to another one, like an HTTP indirection
 36      saying that
 37      <p>"http://www.oasis-open.org/committes/tr.xsl"</p>
 38      <p>should really be looked at</p>
 39      <p>"http://www.oasis-open.org/committes/entity/stylesheets/base/tr.xsl"</p>
 40    </li>
 41    <li>providing a local cache mechanism allowing to load the entities
 42      associated to public identifiers or remote resources, this is a really
 43      important feature for any significant deployment of XML or SGML since it
 44      allows to avoid the aleas and delays associated to fetching remote
 45      resources.</li>
 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>
 47    <li>the older SGML catalogs, the official spec is  SGML Open Technical
 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
 49      James Clark. This is relatively old and not the preferred mode of
 50      operation of libxml.</li>
 51    <li><a href="http://www.oasis-open.org/committees/entity/spec.html">XML
 52      Catalogs</a> is far more flexible, more recent, uses an XML syntax and
 53      should scale quite better. This is the default option of libxml.</li>
 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
 55  catalog in /etc/xml/catalog, and assuming it has been correctly populated,
 56  the processing is completely transparent to the document user. To take a
 57  concrete example, suppose you are authoring a DocBook document, this one
 58  starts with the following DOCTYPE definition:</p><pre>&lt;?xml version='1.0'?&gt;
 59  &lt;!DOCTYPE book PUBLIC "-//Norman Walsh//DTD DocBk XML V3.1.4//EN"
 60            "http://nwalsh.com/docbook/xml/3.1.4/db3xml.dtd"&gt;</pre><p>When validating the document with libxml, the catalog will be
 61  automatically consulted to lookup the public identifier "-//Norman Walsh//DTD
 62  DocBk XML V3.1.4//EN" and the system identifier
 63  "http://nwalsh.com/docbook/xml/3.1.4/db3xml.dtd", and if these entities have
 64  been installed on your system and the catalogs actually point to them, libxml
 65  will fetch them from the local disk.</p><p style="font-size: 10pt"><strong>Note</strong>: Really don't use this
 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
 67  entity, this includes DTD, external parsed entities, stylesheets, etc ... If
 68  your system is correctly configured all the authoring phase and processing
 69  should use only local files, even if your document stays portable because it
 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
 71  regression tests in <code>test/catalogs</code> :</p><pre>&lt;?xml version="1.0"?&gt;
 72  &lt;!DOCTYPE catalog PUBLIC 
 73     "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
 74     "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"&gt;
 75  &lt;catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"&gt;
 76    &lt;public publicId="-//OASIS//DTD DocBook XML V4.1.2//EN"
 77     uri="http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"/&gt;
 78  ...</pre><p>This is the beginning of a catalog for DocBook 4.1.2, XML Catalogs are
 79  written in XML,  there is a specific namespace for catalog elements
 80  "urn:oasis:names:tc:entity:xmlns:xml:catalog". The first entry in this
 81  catalog is a <code>public</code> mapping it allows to associate a Public
 82  Identifier with an URI.</p><pre>...
 83      &lt;rewriteSystem systemIdStartString="http://www.oasis-open.org/docbook/"
 84                     rewritePrefix="file:///usr/share/xml/docbook/"/&gt;
 85  ...</pre><p>A <code>rewriteSystem</code> is a very powerful instruction, it says that
 86  any URI starting with a given prefix should be looked at another  URI
 87  constructed by replacing the prefix with an new one. In effect this acts like
 88  a cache system for a full area of the Web. In practice it is extremely useful
 89  with a file prefix if you have installed a copy of those resources on your
 90  local system.</p><pre>...
 91  &lt;delegatePublic publicIdStartString="-//OASIS//DTD XML Catalog //"
 92                  catalog="file:///usr/share/xml/docbook.xml"/&gt;
 93  &lt;delegatePublic publicIdStartString="-//OASIS//ENTITIES DocBook XML"
 94                  catalog="file:///usr/share/xml/docbook.xml"/&gt;
 95  &lt;delegatePublic publicIdStartString="-//OASIS//DTD DocBook XML"
 96                  catalog="file:///usr/share/xml/docbook.xml"/&gt;
 97  &lt;delegateSystem systemIdStartString="http://www.oasis-open.org/docbook/"
 98                  catalog="file:///usr/share/xml/docbook.xml"/&gt;
 99  &lt;delegateURI uriStartString="http://www.oasis-open.org/docbook/"
100                  catalog="file:///usr/share/xml/docbook.xml"/&gt;
101  ...</pre><p>Delegation is the core features which allows to build a tree of catalogs,
102  easier to maintain than a single catalog, based on Public Identifier, System
103  Identifier or URI prefixes it instructs the catalog software to look up
104  entries in another resource. This feature allow to build hierarchies of
105  catalogs, the set of entries presented should be sufficient to redirect the
106  resolution of all DocBook references to the specific catalog in
107  <code>/usr/share/xml/docbook.xml</code> this one in turn could delegate all
108  references for DocBook 4.2.1 to a specific catalog installed at the same time
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
110  to its own set of catalogs, this can be done by setting the
111  <code>XML_CATALOG_FILES</code> environment variable to a list of catalogs, an
112  empty one should deactivate loading the default <code>/etc/xml/catalog</code>
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
114  make libxml2 output debugging information for each catalog operations, for
115  example:</p><pre>orchis:~/XML -&gt; xmllint --memory --noout test/ent2
116  warning: failed to load external entity "title.xml"
117  orchis:~/XML -&gt; export XML_DEBUG_CATALOG=
118  orchis:~/XML -&gt; xmllint --memory --noout test/ent2
119  Failed to parse catalog /etc/xml/catalog
120  Failed to parse catalog /etc/xml/catalog
121  warning: failed to load external entity "title.xml"
122  Catalogs cleanup
123  orchis:~/XML -&gt; </pre><p>The test/ent2 references an entity, running the parser from memory makes
124  the base URI unavailable and the the "title.xml" entity cannot be loaded.
125  Setting up the debug environment variable allows to detect that an attempt is
126  made to load the <code>/etc/xml/catalog</code> but since it's not present the
127  resolution fails.</p><p>But the most advanced way to debug XML catalog processing is to use the
128  <strong>xmlcatalog</strong> command shipped with libxml2, it allows to load
129  catalogs and make resolution queries to see what is going on. This is also
130  used for the regression tests:</p><pre>orchis:~/XML -&gt; ./xmlcatalog test/catalogs/docbook.xml \
131                     "-//OASIS//DTD DocBook XML V4.1.2//EN"
132  http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd
133  orchis:~/XML -&gt; </pre><p>For debugging what is going on, adding one -v flags increase the verbosity
134  level to indicate the processing done (adding a second flag also indicate
135  what elements are recognized at parsing):</p><pre>orchis:~/XML -&gt; ./xmlcatalog -v test/catalogs/docbook.xml \
136                     "-//OASIS//DTD DocBook XML V4.1.2//EN"
137  Parsing catalog test/catalogs/docbook.xml's content
138  Found public match -//OASIS//DTD DocBook XML V4.1.2//EN
139  http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd
140  Catalogs cleanup
141  orchis:~/XML -&gt; </pre><p>A shell interface is also available to debug and process multiple queries
142  (and for regression tests):</p><pre>orchis:~/XML -&gt; ./xmlcatalog -shell test/catalogs/docbook.xml \
143                     "-//OASIS//DTD DocBook XML V4.1.2//EN"
144  &gt; help   
145  Commands available:
146  public PublicID: make a PUBLIC identifier lookup
147  system SystemID: make a SYSTEM identifier lookup
148  resolve PublicID SystemID: do a full resolver lookup
149  add 'type' 'orig' 'replace' : add an entry
150  del 'values' : remove values
151  dump: print the current catalog state
152  debug: increase the verbosity level
153  quiet: decrease the verbosity level
154  exit:  quit the shell
155  &gt; public "-//OASIS//DTD DocBook XML V4.1.2//EN"
156  http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd
157  &gt; quit
158  orchis:~/XML -&gt; </pre><p>This should be sufficient for most debugging purpose, this was actually
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
160  manage them or use  <strong>xmlcatalog</strong> for this. The basic step is
161  to create a catalog the -create option provide this facility:</p><pre>orchis:~/XML -&gt; ./xmlcatalog --create tst.xml
162  &lt;?xml version="1.0"?&gt;
163  &lt;!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
164           "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"&gt;
165  &lt;catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"/&gt;
166  orchis:~/XML -&gt; </pre><p>By default xmlcatalog does not overwrite the original catalog and save the
167  result on the standard output, this can be overridden using the -noout
168  option. The <code>-add</code> command allows to add entries in the
169  catalog:</p><pre>orchis:~/XML -&gt; ./xmlcatalog --noout --create --add "public" \
170    "-//OASIS//DTD DocBook XML V4.1.2//EN" \
171    http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd tst.xml
172  orchis:~/XML -&gt; cat tst.xml
173  &lt;?xml version="1.0"?&gt;
174  &lt;!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN" \
175    "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"&gt;
176  &lt;catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"&gt;
177  &lt;public publicId="-//OASIS//DTD DocBook XML V4.1.2//EN"
178          uri="http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"/&gt;
179  &lt;/catalog&gt;
180  orchis:~/XML -&gt; </pre><p>The <code>-add</code> option will always take 3 parameters even if some of
181  the XML Catalog constructs (like nextCatalog) will have only a single
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
183  catalog:</p><pre>orchis:~/XML -&gt; ./xmlcatalog --del \
184    "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" tst.xml
185  &lt;?xml version="1.0"?&gt;
186  &lt;!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
187      "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"&gt;
188  &lt;catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"/&gt;
189  orchis:~/XML -&gt; </pre><p>The catalog is now empty. Note that the matching of <code>-del</code> is
190  exact and would have worked in a similar fashion with the Public ID
191  string.</p><p>This is rudimentary but should be sufficient to manage a not too complex
192  catalog tree of resources.</p><h3><a name="implemento" id="implemento">The implementor corner quick review of the
193  API:</a></h3><p>First, and like for every other module of libxml, there is an
194  automatically generated <a href="html/libxml-catalog.html">API page for
195  catalog support</a>.</p><p>The header for the catalog interfaces should be included as:</p><pre>#include &lt;libxml/catalog.h&gt;</pre><p>The API is voluntarily kept very simple. First it is not obvious that
196  applications really need access to it since it is the default behaviour of
197  libxml2 (Note: it is possible to completely override libxml2 default catalog
198  by using <a href="html/libxml-parser.html">xmlSetExternalEntityLoader</a> to
199  plug an application specific resolver).</p><p>Basically libxml2 support 2 catalog lists:</p><ul>
200    <li>the default one, global shared by all the application</li>
201    <li>a per-document catalog, this one is built if the document uses the
202      <code>oasis-xml-catalog</code> PIs to specify its own catalog list, it is
203      associated to the parser context and destroyed when the parsing context
204      is destroyed.</li>
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
206  used at startup to initialize the catalog, if the catalog should be
207  initialized with specific values xmlLoadCatalog()  or xmlLoadCatalogs()
208  should be called before xmlInitializeCatalog() which would otherwise do a
209  default initialization first.</p><p>The xmlCatalogAddLocal() call is used by the parser to grow the document
210  own catalog list if needed.</p><h4>Preferences setup:</h4><p>The XML Catalog spec requires the possibility to select default
211  preferences between  public and system delegation,
212  xmlCatalogSetDefaultPrefer() allows this, xmlCatalogSetDefaults() and
213  xmlCatalogGetDefaults() allow to control  if XML Catalogs resolution should
214  be forbidden, allowed for global catalog, for document catalog or both, the
215  default is to allow both.</p><p>And of course xmlCatalogSetDebug() allows to generate debug messages
216  (through the xmlGenericError() mechanism).</p><h4>Querying routines:</h4><p>xmlCatalogResolve(), xmlCatalogResolveSystem(), xmlCatalogResolvePublic()
217  and xmlCatalogResolveURI() are relatively explicit if you read the XML
218  Catalog specification they correspond to section 7 algorithms, they should
219  also work if you have loaded an SGML catalog with a simplified semantic.</p><p>xmlCatalogLocalResolve() and xmlCatalogLocalResolveURI() are the same but
220  operate on the document catalog list</p><h4>Cleanup and Miscellaneous:</h4><p>xmlCatalogCleanup() free-up the global catalog, xmlCatalogFreeLocal() is
221  the per-document equivalent.</p><p>xmlCatalogAdd() and xmlCatalogRemove() are used to dynamically modify the
222  first catalog in the global list, and xmlCatalogDump() allows to dump a
223  catalog state, those routines are primarily designed for xmlcatalog, I'm not
224  sure that exposing more complex interfaces (like navigation ones) would be
225  really useful.</p><p>The xmlParseCatalogFile() is a function used to load XML Catalog files,
226  it's similar as xmlParseFile() except it bypass all catalog lookups, it's
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
228  try to avoid troubles in multithreaded environments. The code is now thread
229  safe assuming that the libxml2 library has been compiled with threads
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
231  literature to point at:</p><ul>
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
233      need for catalogs</a>, it provides a lot of context information even if
234      I don't agree with everything presented. Norm also wrote a more recent
235      article <a href="http://wwws.sun.com/software/xml/developers/resolver/article/">XML
236      entities and URI resolvers</a> describing them.</li>
237    <li>An <a href="http://home.ccil.org/~cowan/XML/XCatalog.html">old XML
238      catalog proposal</a> from John Cowan</li>
239    <li>The <a href="http://www.rddl.org/">Resource Directory Description
240      Language</a> (RDDL) another catalog system but more oriented toward
241      providing metadata for XML namespaces.</li>
242    <li>the page from the OASIS Technical <a href="http://www.oasis-open.org/committees/entity/">Committee on Entity
243      Resolution</a> who maintains XML Catalog, you will find pointers to the
244      specification update, some background and pointers to others tools
245      providing XML Catalog support</li>
246    <li>There is a <a href="buildDocBookCatalog">shell script</a> to generate
247      XML Catalogs for DocBook 4.1.2 . If it can write to the /etc/xml/
248      directory, it will set-up /etc/xml/catalog and /etc/xml/docbook based on
249      the resources found on the system. Otherwise it will just create
250      ~/xmlcatalog and ~/dbkxmlcatalog and doing:
251      <p><code>export XML_CATALOG_FILES=$HOME/xmlcatalog</code></p>
252      <p>should allow to process DocBook documentations without requiring
253      network accesses for the DTD or stylesheets</p>
254    </li>
255    <li>I have uploaded <a href="ftp://xmlsoft.org/libxml2/test/dbk412catalog.tar.gz">a
256      small tarball</a> containing XML Catalogs for DocBook 4.1.2 which seems
257      to work fine for me too</li>
258    <li>The <a href="http://www.xmlsoft.org/xmlcatalog_man.html">xmlcatalog
259      manual page</a></li>
260  </ul><p>If you have suggestions for corrections or additions, simply contact
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>