Annotation of embedaddon/expat/doc/reference.html, revision 1.1

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        !             6: <!-- Copyright 1999,2000 Clark Cooper <coopercc@netheaven.com>
        !             7:      All rights reserved.
        !             8:      This is free software. You may distribute or modify according to
        !             9:      the terms of the MIT/X License -->
        !            10:   <title>Expat XML Parser</title>
        !            11:   <meta name="author" content="Clark Cooper, coopercc@netheaven.com" />
        !            12:   <meta http-equiv="Content-Style-Type" content="text/css" />
        !            13:   <link href="style.css" rel="stylesheet" type="text/css" />
        !            14: </head>
        !            15: <body>
        !            16:   <table cellspacing="0" cellpadding="0" width="100%">
        !            17:     <tr>
        !            18:       <td class="corner"><img src="expat.png" alt="(Expat logo)" /></td>
        !            19:       <td class="banner"><h1>The Expat XML Parser</h1></td>
        !            20:     </tr>
        !            21:     <tr>
        !            22:       <td class="releaseno">Release 2.0.1</td>
        !            23:       <td></td>
        !            24:     </tr>
        !            25:   </table>
        !            26: <div class="content">
        !            27: 
        !            28: <p>Expat is a library, written in C, for parsing XML documents. It's
        !            29: the underlying XML parser for the open source Mozilla project, Perl's
        !            30: <code>XML::Parser</code>, Python's <code>xml.parsers.expat</code>, and
        !            31: other open-source XML parsers.</p>
        !            32: 
        !            33: <p>This library is the creation of James Clark, who's also given us
        !            34: groff (an nroff look-alike), Jade (an implemention of ISO's DSSSL
        !            35: stylesheet language for SGML), XP (a Java XML parser package), XT (a
        !            36: Java XSL engine).  James was also the technical lead on the XML
        !            37: Working Group at W3C that produced the XML specification.</p>
        !            38: 
        !            39: <p>This is free software, licensed under the <a
        !            40: href="../COPYING">MIT/X Consortium license</a>. You may download it
        !            41: from <a href="http://www.libexpat.org/">the Expat home page</a>.
        !            42: </p>
        !            43: 
        !            44: <p>The bulk of this document was originally commissioned as an article
        !            45: by <a href="http://www.xml.com/">XML.com</a>. They graciously allowed
        !            46: Clark Cooper to retain copyright and to distribute it with Expat.
        !            47: This version has been substantially extended to include documentation
        !            48: on features which have been added since the original article was
        !            49: published, and additional information on using the original
        !            50: interface.</p>
        !            51: 
        !            52: <hr />
        !            53: <h2>Table of Contents</h2>
        !            54: <ul>
        !            55:   <li><a href="#overview">Overview</a></li>
        !            56:   <li><a href="#building">Building and Installing</a></li>
        !            57:   <li><a href="#using">Using Expat</a></li>
        !            58:   <li><a href="#reference">Reference</a>
        !            59:   <ul>
        !            60:     <li><a href="#creation">Parser Creation Functions</a>
        !            61:     <ul>
        !            62:       <li><a href="#XML_ParserCreate">XML_ParserCreate</a></li>
        !            63:       <li><a href="#XML_ParserCreateNS">XML_ParserCreateNS</a></li>
        !            64:       <li><a href="#XML_ParserCreate_MM">XML_ParserCreate_MM</a></li>
        !            65:       <li><a href="#XML_ExternalEntityParserCreate">XML_ExternalEntityParserCreate</a></li>
        !            66:       <li><a href="#XML_ParserFree">XML_ParserFree</a></li>
        !            67:       <li><a href="#XML_ParserReset">XML_ParserReset</a></li>
        !            68:     </ul>
        !            69:     </li>
        !            70:     <li><a href="#parsing">Parsing Functions</a>
        !            71:     <ul>
        !            72:       <li><a href="#XML_Parse">XML_Parse</a></li>
        !            73:       <li><a href="#XML_ParseBuffer">XML_ParseBuffer</a></li>
        !            74:       <li><a href="#XML_GetBuffer">XML_GetBuffer</a></li>
        !            75:       <li><a href="#XML_StopParser">XML_StopParser</a></li>
        !            76:       <li><a href="#XML_ResumeParser">XML_ResumeParser</a></li>
        !            77:       <li><a href="#XML_GetParsingStatus">XML_GetParsingStatus</a></li>
        !            78:     </ul>
        !            79:     </li>
        !            80:     <li><a href="#setting">Handler Setting Functions</a>
        !            81:     <ul>
        !            82:       <li><a href="#XML_SetStartElementHandler">XML_SetStartElementHandler</a></li>
        !            83:       <li><a href="#XML_SetEndElementHandler">XML_SetEndElementHandler</a></li>
        !            84:       <li><a href="#XML_SetElementHandler">XML_SetElementHandler</a></li>
        !            85:       <li><a href="#XML_SetCharacterDataHandler">XML_SetCharacterDataHandler</a></li>
        !            86:       <li><a href="#XML_SetProcessingInstructionHandler">XML_SetProcessingInstructionHandler</a></li>
        !            87:       <li><a href="#XML_SetCommentHandler">XML_SetCommentHandler</a></li>
        !            88:       <li><a href="#XML_SetStartCdataSectionHandler">XML_SetStartCdataSectionHandler</a></li>
        !            89:       <li><a href="#XML_SetEndCdataSectionHandler">XML_SetEndCdataSectionHandler</a></li>
        !            90:       <li><a href="#XML_SetCdataSectionHandler">XML_SetCdataSectionHandler</a></li>
        !            91:       <li><a href="#XML_SetDefaultHandler">XML_SetDefaultHandler</a></li>
        !            92:       <li><a href="#XML_SetDefaultHandlerExpand">XML_SetDefaultHandlerExpand</a></li>
        !            93:       <li><a href="#XML_SetExternalEntityRefHandler">XML_SetExternalEntityRefHandler</a></li>
        !            94:       <li><a href="#XML_SetExternalEntityRefHandlerArg">XML_SetExternalEntityRefHandlerArg</a></li>
        !            95:       <li><a href="#XML_SetSkippedEntityHandler">XML_SetSkippedEntityHandler</a></li>
        !            96:       <li><a href="#XML_SetUnknownEncodingHandler">XML_SetUnknownEncodingHandler</a></li>
        !            97:       <li><a href="#XML_SetStartNamespaceDeclHandler">XML_SetStartNamespaceDeclHandler</a></li>
        !            98:       <li><a href="#XML_SetEndNamespaceDeclHandler">XML_SetEndNamespaceDeclHandler</a></li>
        !            99:       <li><a href="#XML_SetNamespaceDeclHandler">XML_SetNamespaceDeclHandler</a></li>
        !           100:       <li><a href="#XML_SetXmlDeclHandler">XML_SetXmlDeclHandler</a></li>                
        !           101:       <li><a href="#XML_SetStartDoctypeDeclHandler">XML_SetStartDoctypeDeclHandler</a></li>
        !           102:       <li><a href="#XML_SetEndDoctypeDeclHandler">XML_SetEndDoctypeDeclHandler</a></li>
        !           103:       <li><a href="#XML_SetDoctypeDeclHandler">XML_SetDoctypeDeclHandler</a></li>
        !           104:       <li><a href="#XML_SetElementDeclHandler">XML_SetElementDeclHandler</a></li>
        !           105:       <li><a href="#XML_SetAttlistDeclHandler">XML_SetAttlistDeclHandler</a></li>
        !           106:       <li><a href="#XML_SetEntityDeclHandler">XML_SetEntityDeclHandler</a></li>
        !           107:       <li><a href="#XML_SetUnparsedEntityDeclHandler">XML_SetUnparsedEntityDeclHandler</a></li>
        !           108:       <li><a href="#XML_SetNotationDeclHandler">XML_SetNotationDeclHandler</a></li>
        !           109:       <li><a href="#XML_SetNotStandaloneHandler">XML_SetNotStandaloneHandler</a></li>
        !           110:     </ul>
        !           111:     </li>
        !           112:     <li><a href="#position">Parse Position and Error Reporting Functions</a>
        !           113:     <ul>
        !           114:       <li><a href="#XML_GetErrorCode">XML_GetErrorCode</a></li>
        !           115:       <li><a href="#XML_ErrorString">XML_ErrorString</a></li>
        !           116:       <li><a href="#XML_GetCurrentByteIndex">XML_GetCurrentByteIndex</a></li>
        !           117:       <li><a href="#XML_GetCurrentLineNumber">XML_GetCurrentLineNumber</a></li>
        !           118:       <li><a href="#XML_GetCurrentColumnNumber">XML_GetCurrentColumnNumber</a></li>
        !           119:       <li><a href="#XML_GetCurrentByteCount">XML_GetCurrentByteCount</a></li>
        !           120:       <li><a href="#XML_GetInputContext">XML_GetInputContext</a></li>
        !           121:     </ul>
        !           122:     </li>
        !           123:     <li><a href="#miscellaneous">Miscellaneous Functions</a>
        !           124:     <ul>
        !           125:       <li><a href="#XML_SetUserData">XML_SetUserData</a></li>
        !           126:       <li><a href="#XML_GetUserData">XML_GetUserData</a></li>
        !           127:       <li><a href="#XML_UseParserAsHandlerArg">XML_UseParserAsHandlerArg</a></li>
        !           128:       <li><a href="#XML_SetBase">XML_SetBase</a></li>
        !           129:       <li><a href="#XML_GetBase">XML_GetBase</a></li>
        !           130:       <li><a href="#XML_GetSpecifiedAttributeCount">XML_GetSpecifiedAttributeCount</a></li>
        !           131:       <li><a href="#XML_GetIdAttributeIndex">XML_GetIdAttributeIndex</a></li>
        !           132:       <li><a href="#XML_SetEncoding">XML_SetEncoding</a></li>
        !           133:       <li><a href="#XML_SetParamEntityParsing">XML_SetParamEntityParsing</a></li>
        !           134:       <li><a href="#XML_UseForeignDTD">XML_UseForeignDTD</a></li>
        !           135:       <li><a href="#XML_SetReturnNSTriplet">XML_SetReturnNSTriplet</a></li>
        !           136:       <li><a href="#XML_DefaultCurrent">XML_DefaultCurrent</a></li>
        !           137:       <li><a href="#XML_ExpatVersion">XML_ExpatVersion</a></li>
        !           138:       <li><a href="#XML_ExpatVersionInfo">XML_ExpatVersionInfo</a></li>
        !           139:       <li><a href="#XML_GetFeatureList">XML_GetFeatureList</a></li>
        !           140:       <li><a href="#XML_FreeContentModel">XML_FreeContentModel</a></li>
        !           141:       <li><a href="#XML_MemMalloc">XML_MemMalloc</a></li>
        !           142:       <li><a href="#XML_MemRealloc">XML_MemRealloc</a></li>
        !           143:       <li><a href="#XML_MemFree">XML_MemFree</a></li>
        !           144:     </ul>
        !           145:     </li>
        !           146:   </ul>  
        !           147:   </li>
        !           148: </ul>
        !           149: 
        !           150: <hr />
        !           151: <h2><a name="overview">Overview</a></h2>
        !           152: 
        !           153: <p>Expat is a stream-oriented parser. You register callback (or
        !           154: handler) functions with the parser and then start feeding it the
        !           155: document.  As the parser recognizes parts of the document, it will
        !           156: call the appropriate handler for that part (if you've registered one.) 
        !           157: The document is fed to the parser in pieces, so you can start parsing
        !           158: before you have all the document. This also allows you to parse really
        !           159: huge documents that won't fit into memory.</p>
        !           160: 
        !           161: <p>Expat can be intimidating due to the many kinds of handlers and
        !           162: options you can set. But you only need to learn four functions in
        !           163: order to do 90% of what you'll want to do with it:</p>
        !           164: 
        !           165: <dl>
        !           166: 
        !           167: <dt><code><a href= "#XML_ParserCreate"
        !           168:              >XML_ParserCreate</a></code></dt>
        !           169:   <dd>Create a new parser object.</dd>
        !           170: 
        !           171: <dt><code><a href= "#XML_SetElementHandler"
        !           172:              >XML_SetElementHandler</a></code></dt>
        !           173:   <dd>Set handlers for start and end tags.</dd>
        !           174: 
        !           175: <dt><code><a href= "#XML_SetCharacterDataHandler"
        !           176:              >XML_SetCharacterDataHandler</a></code></dt>
        !           177:   <dd>Set handler for text.</dd>
        !           178: 
        !           179: <dt><code><a href= "#XML_Parse"
        !           180:              >XML_Parse</a></code></dt>
        !           181:   <dd>Pass a buffer full of document to the parser</dd>
        !           182: </dl>
        !           183: 
        !           184: <p>These functions and others are described in the <a
        !           185: href="#reference">reference</a> part of this document. The reference
        !           186: section also describes in detail the parameters passed to the
        !           187: different types of handlers.</p>
        !           188: 
        !           189: <p>Let's look at a very simple example program that only uses 3 of the
        !           190: above functions (it doesn't need to set a character handler.) The
        !           191: program <a href="../examples/outline.c">outline.c</a> prints an
        !           192: element outline, indenting child elements to distinguish them from the
        !           193: parent element that contains them. The start handler does all the
        !           194: work.  It prints two indenting spaces for every level of ancestor
        !           195: elements, then it prints the element and attribute
        !           196: information. Finally it increments the global <code>Depth</code>
        !           197: variable.</p>
        !           198: 
        !           199: <pre class="eg">
        !           200: int Depth;
        !           201: 
        !           202: void XMLCALL
        !           203: start(void *data, const char *el, const char **attr) {
        !           204:   int i;
        !           205: 
        !           206:   for (i = 0; i &lt; Depth; i++)
        !           207:     printf("  ");
        !           208: 
        !           209:   printf("%s", el);
        !           210: 
        !           211:   for (i = 0; attr[i]; i += 2) {
        !           212:     printf(" %s='%s'", attr[i], attr[i + 1]);
        !           213:   }
        !           214: 
        !           215:   printf("\n");
        !           216:   Depth++;
        !           217: }  /* End of start handler */
        !           218: </pre>
        !           219: 
        !           220: <p>The end tag simply does the bookkeeping work of decrementing
        !           221: <code>Depth</code>.</p>
        !           222: <pre class="eg">
        !           223: void XMLCALL
        !           224: end(void *data, const char *el) {
        !           225:   Depth--;
        !           226: }  /* End of end handler */
        !           227: </pre>
        !           228: 
        !           229: <p>Note the <code>XMLCALL</code> annotation used for the callbacks.
        !           230: This is used to ensure that the Expat and the callbacks are using the
        !           231: same calling convention in case the compiler options used for Expat
        !           232: itself and the client code are different.  Expat tries not to care
        !           233: what the default calling convention is, though it may require that it
        !           234: be compiled with a default convention of "cdecl" on some platforms.
        !           235: For code which uses Expat, however, the calling convention is
        !           236: specified by the <code>XMLCALL</code> annotation on most platforms;
        !           237: callbacks should be defined using this annotation.</p>
        !           238: 
        !           239: <p>The <code>XMLCALL</code> annotation was added in Expat 1.95.7, but
        !           240: existing working Expat applications don't need to add it (since they
        !           241: are already using the "cdecl" calling convention, or they wouldn't be
        !           242: working).  The annotation is only needed if the default calling
        !           243: convention may be something other than "cdecl".  To use the annotation
        !           244: safely with older versions of Expat, you can conditionally define it
        !           245: <em>after</em> including Expat's header file:</p>
        !           246: 
        !           247: <pre class="eg">
        !           248: #include &lt;expat.h&gt;
        !           249: 
        !           250: #ifndef XMLCALL
        !           251: #if defined(_MSC_EXTENSIONS) &amp;&amp; !defined(__BEOS__) &amp;&amp; !defined(__CYGWIN__)
        !           252: #define XMLCALL __cdecl
        !           253: #elif defined(__GNUC__)
        !           254: #define XMLCALL __attribute__((cdecl))
        !           255: #else
        !           256: #define XMLCALL
        !           257: #endif
        !           258: #endif
        !           259: </pre>
        !           260: 
        !           261: <p>After creating the parser, the main program just has the job of
        !           262: shoveling the document to the parser so that it can do its work.</p>
        !           263: 
        !           264: <hr />
        !           265: <h2><a name="building">Building and Installing Expat</a></h2>
        !           266: 
        !           267: <p>The Expat distribution comes as a compressed (with GNU gzip) tar
        !           268: file.  You may download the latest version from <a href=
        !           269: "http://sourceforge.net/projects/expat/" >Source Forge</a>.  After
        !           270: unpacking this, cd into the directory. Then follow either the Win32
        !           271: directions or Unix directions below.</p>
        !           272: 
        !           273: <h3>Building under Win32</h3>
        !           274: 
        !           275: <p>If you're using the GNU compiler under cygwin, follow the Unix
        !           276: directions in the next section. Otherwise if you have Microsoft's
        !           277: Developer Studio installed, then from Windows Explorer double-click on
        !           278: "expat.dsp" in the lib directory and build and install in the usual
        !           279: manner.</p>
        !           280: 
        !           281: <p>Alternatively, you may download the Win32 binary package that
        !           282: contains the "expat.h" include file and a pre-built DLL.</p>
        !           283: 
        !           284: <h3>Building under Unix (or GNU)</h3>
        !           285: 
        !           286: <p>First you'll need to run the configure shell script in order to
        !           287: configure the Makefiles and headers for your system.</p>
        !           288: 
        !           289: <p>If you're happy with all the defaults that configure picks for you,
        !           290: and you have permission on your system to install into /usr/local, you
        !           291: can install Expat with this sequence of commands:</p>
        !           292: 
        !           293: <pre class="eg">
        !           294: ./configure
        !           295: make
        !           296: make install
        !           297: </pre>
        !           298: 
        !           299: <p>There are some options that you can provide to this script, but the
        !           300: only one we'll mention here is the <code>--prefix</code> option. You
        !           301: can find out all the options available by running configure with just
        !           302: the <code>--help</code> option.</p>
        !           303: 
        !           304: <p>By default, the configure script sets things up so that the library
        !           305: gets installed in <code>/usr/local/lib</code> and the associated
        !           306: header file in <code>/usr/local/include</code>.  But if you were to
        !           307: give the option, <code>--prefix=/home/me/mystuff</code>, then the
        !           308: library and header would get installed in
        !           309: <code>/home/me/mystuff/lib</code> and
        !           310: <code>/home/me/mystuff/include</code> respectively.</p>
        !           311: 
        !           312: <h3>Configuring Expat Using the Pre-Processor</h3>
        !           313: 
        !           314: <p>Expat's feature set can be configured using a small number of
        !           315: pre-processor definitions.  The definition of this symbols does not
        !           316: affect the set of entry points for Expat, only the behavior of the API
        !           317: and the definition of character types in the case of
        !           318: <code>XML_UNICODE_WCHAR_T</code>.  The symbols are:</p>
        !           319: 
        !           320: <dl class="cpp-symbols">
        !           321: <dt>XML_DTD</dt>
        !           322: <dd>Include support for using and reporting DTD-based content.  If
        !           323: this is defined, default attribute values from an external DTD subset
        !           324: are reported and attribute value normalization occurs based on the
        !           325: type of attributes defined in the external subset.  Without
        !           326: this, Expat has a smaller memory footprint and can be faster, but will
        !           327: not load external entities or process conditional sections.  This does
        !           328: not affect the set of functions available in the API.</dd>
        !           329: 
        !           330: <dt>XML_NS</dt>
        !           331: <dd>When defined, support for the <cite><a href=
        !           332: "http://www.w3.org/TR/REC-xml-names/" >Namespaces in XML</a></cite>
        !           333: specification is included.</dd>
        !           334: 
        !           335: <dt>XML_UNICODE</dt>
        !           336: <dd>When defined, character data reported to the application is
        !           337: encoded in UTF-16 using wide characters of the type
        !           338: <code>XML_Char</code>.  This is implied if
        !           339: <code>XML_UNICODE_WCHAR_T</code> is defined.</dd>
        !           340: 
        !           341: <dt>XML_UNICODE_WCHAR_T</dt>
        !           342: <dd>If defined, causes the <code>XML_Char</code> character type to be
        !           343: defined using the <code>wchar_t</code> type; otherwise, <code>unsigned
        !           344: short</code> is used.  Defining this implies
        !           345: <code>XML_UNICODE</code>.</dd>
        !           346: 
        !           347: <dt>XML_LARGE_SIZE</dt>
        !           348: <dd>If defined, causes the <code>XML_Size</code> and <code>XML_Index</code>
        !           349: integer types to be at least 64 bits in size. This is intended to support
        !           350: processing of very large input streams, where the return values of
        !           351: <code><a href="#XML_GetCurrentByteIndex" >XML_GetCurrentByteIndex</a></code>,
        !           352: <code><a href="#XML_GetCurrentLineNumber" >XML_GetCurrentLineNumber</a></code> and
        !           353: <code><a href="#XML_GetCurrentColumnNumber" >XML_GetCurrentColumnNumber</a></code>
        !           354: could overflow. It may not be supported by all compilers, and is turned
        !           355: off by default.</dd>
        !           356: 
        !           357: <dt>XML_CONTEXT_BYTES</dt>
        !           358: <dd>The number of input bytes of markup context which the parser will
        !           359: ensure are available for reporting via <code><a href=
        !           360: "#XML_GetInputContext" >XML_GetInputContext</a></code>.  This is
        !           361: normally set to 1024, and must be set to a positive interger.  If this
        !           362: is not defined, the input context will not be available and <code><a
        !           363: href= "#XML_GetInputContext" >XML_GetInputContext</a></code> will
        !           364: always report NULL.  Without this, Expat has a smaller memory
        !           365: footprint and can be faster.</dd>
        !           366: 
        !           367: <dt>XML_STATIC</dt>
        !           368: <dd>On Windows, this should be set if Expat is going to be linked
        !           369: statically with the code that calls it; this is required to get all
        !           370: the right MSVC magic annotations correct.  This is ignored on other
        !           371: platforms.</dd>
        !           372: </dl>
        !           373: 
        !           374: <hr />
        !           375: <h2><a name="using">Using Expat</a></h2>
        !           376: 
        !           377: <h3>Compiling and Linking Against Expat</h3>
        !           378: 
        !           379: <p>Unless you installed Expat in a location not expected by your
        !           380: compiler and linker, all you have to do to use Expat in your programs
        !           381: is to include the Expat header (<code>#include &lt;expat.h&gt;</code>)
        !           382: in your files that make calls to it and to tell the linker that it
        !           383: needs to link against the Expat library.  On Unix systems, this would
        !           384: usually be done with the <code>-lexpat</code> argument.  Otherwise,
        !           385: you'll need to tell the compiler where to look for the Expat header
        !           386: and the linker where to find the Expat library.  You may also need to
        !           387: take steps to tell the operating system where to find this library at
        !           388: run time.</p>
        !           389: 
        !           390: <p>On a Unix-based system, here's what a Makefile might look like when
        !           391: Expat is installed in a standard location:</p>
        !           392: 
        !           393: <pre class="eg">
        !           394: CC=cc
        !           395: LDFLAGS=
        !           396: LIBS= -lexpat
        !           397: xmlapp: xmlapp.o
        !           398:         $(CC) $(LDFLAGS) -o xmlapp xmlapp.o $(LIBS)
        !           399: </pre>
        !           400: 
        !           401: <p>If you installed Expat in, say, <code>/home/me/mystuff</code>, then
        !           402: the Makefile would look like this:</p>
        !           403: 
        !           404: <pre class="eg">
        !           405: CC=cc
        !           406: CFLAGS= -I/home/me/mystuff/include
        !           407: LDFLAGS=
        !           408: LIBS= -L/home/me/mystuff/lib -lexpat
        !           409: xmlapp: xmlapp.o
        !           410:         $(CC) $(LDFLAGS) -o xmlapp xmlapp.o $(LIBS)
        !           411: </pre>
        !           412: 
        !           413: <p>You'd also have to set the environment variable
        !           414: <code>LD_LIBRARY_PATH</code> to <code>/home/me/mystuff/lib</code> (or
        !           415: to <code>${LD_LIBRARY_PATH}:/home/me/mystuff/lib</code> if
        !           416: LD_LIBRARY_PATH already has some directories in it) in order to run
        !           417: your application.</p>
        !           418: 
        !           419: <h3>Expat Basics</h3>
        !           420: 
        !           421: <p>As we saw in the example in the overview, the first step in parsing
        !           422: an XML document with Expat is to create a parser object. There are <a
        !           423: href="#creation">three functions</a> in the Expat API for creating a
        !           424: parser object.  However, only two of these (<code><a href=
        !           425: "#XML_ParserCreate" >XML_ParserCreate</a></code> and <code><a href=
        !           426: "#XML_ParserCreateNS" >XML_ParserCreateNS</a></code>) can be used for
        !           427: constructing a parser for a top-level document.  The object returned
        !           428: by these functions is an opaque pointer (i.e. "expat.h" declares it as
        !           429: void *) to data with further internal structure. In order to free the
        !           430: memory associated with this object you must call <code><a href=
        !           431: "#XML_ParserFree" >XML_ParserFree</a></code>. Note that if you have
        !           432: provided any <a href="#userdata">user data</a> that gets stored in the
        !           433: parser, then your application is responsible for freeing it prior to
        !           434: calling <code>XML_ParserFree</code>.</p>
        !           435: 
        !           436: <p>The objects returned by the parser creation functions are good for
        !           437: parsing only one XML document or external parsed entity. If your
        !           438: application needs to parse many XML documents, then it needs to create
        !           439: a parser object for each one. The best way to deal with this is to
        !           440: create a higher level object that contains all the default
        !           441: initialization you want for your parser objects.</p>
        !           442: 
        !           443: <p>Walking through a document hierarchy with a stream oriented parser
        !           444: will require a good stack mechanism in order to keep track of current
        !           445: context.  For instance, to answer the simple question, "What element
        !           446: does this text belong to?" requires a stack, since the parser may have
        !           447: descended into other elements that are children of the current one and
        !           448: has encountered this text on the way out.</p>
        !           449: 
        !           450: <p>The things you're likely to want to keep on a stack are the
        !           451: currently opened element and it's attributes. You push this
        !           452: information onto the stack in the start handler and you pop it off in
        !           453: the end handler.</p>
        !           454: 
        !           455: <p>For some tasks, it is sufficient to just keep information on what
        !           456: the depth of the stack is (or would be if you had one.) The outline
        !           457: program shown above presents one example. Another such task would be
        !           458: skipping over a complete element. When you see the start tag for the
        !           459: element you want to skip, you set a skip flag and record the depth at
        !           460: which the element started.  When the end tag handler encounters the
        !           461: same depth, the skipped element has ended and the flag may be
        !           462: cleared. If you follow the convention that the root element starts at
        !           463: 1, then you can use the same variable for skip flag and skip
        !           464: depth.</p>
        !           465: 
        !           466: <pre class="eg">
        !           467: void
        !           468: init_info(Parseinfo *info) {
        !           469:   info->skip = 0;
        !           470:   info->depth = 1;
        !           471:   /* Other initializations here */
        !           472: }  /* End of init_info */
        !           473: 
        !           474: void XMLCALL
        !           475: rawstart(void *data, const char *el, const char **attr) {
        !           476:   Parseinfo *inf = (Parseinfo *) data;
        !           477: 
        !           478:   if (! inf->skip) {
        !           479:     if (should_skip(inf, el, attr)) {
        !           480:       inf->skip = inf->depth;
        !           481:     }
        !           482:     else
        !           483:       start(inf, el, attr);     /* This does rest of start handling */
        !           484:   }
        !           485: 
        !           486:   inf->depth++;
        !           487: }  /* End of rawstart */
        !           488: 
        !           489: void XMLCALL
        !           490: rawend(void *data, const char *el) {
        !           491:   Parseinfo *inf = (Parseinfo *) data;
        !           492: 
        !           493:   inf->depth--;
        !           494: 
        !           495:   if (! inf->skip)
        !           496:     end(inf, el);              /* This does rest of end handling */
        !           497: 
        !           498:   if (inf->skip == inf->depth)
        !           499:     inf->skip = 0;
        !           500: }  /* End rawend */
        !           501: </pre>
        !           502: 
        !           503: <p>Notice in the above example the difference in how depth is
        !           504: manipulated in the start and end handlers. The end tag handler should
        !           505: be the mirror image of the start tag handler. This is necessary to
        !           506: properly model containment. Since, in the start tag handler, we
        !           507: incremented depth <em>after</em> the main body of start tag code, then
        !           508: in the end handler, we need to manipulate it <em>before</em> the main
        !           509: body.  If we'd decided to increment it first thing in the start
        !           510: handler, then we'd have had to decrement it last thing in the end
        !           511: handler.</p>
        !           512: 
        !           513: <h3 id="userdata">Communicating between handlers</h3>
        !           514: 
        !           515: <p>In order to be able to pass information between different handlers
        !           516: without using globals, you'll need to define a data structure to hold
        !           517: the shared variables. You can then tell Expat (with the <code><a href=
        !           518: "#XML_SetUserData" >XML_SetUserData</a></code> function) to pass a
        !           519: pointer to this structure to the handlers.  This is the first
        !           520: argument received by most handlers.  In the <a href="#reference"
        !           521: >reference section</a>, an argument to a callback function is named
        !           522: <code>userData</code> and have type <code>void *</code> if the user
        !           523: data is passed; it will have the type <code>XML_Parser</code> if the
        !           524: parser itself is passed.  When the parser is passed, the user data may
        !           525: be retrieved using <code><a href="#XML_GetUserData"
        !           526: >XML_GetUserData</a></code>.</p>
        !           527: 
        !           528: <p>One common case where multiple calls to a single handler may need
        !           529: to communicate using an application data structure is the case when
        !           530: content passed to the character data handler (set by <code><a href=
        !           531: "#XML_SetCharacterDataHandler"
        !           532: >XML_SetCharacterDataHandler</a></code>) needs to be accumulated.  A
        !           533: common first-time mistake with any of the event-oriented interfaces to
        !           534: an XML parser is to expect all the text contained in an element to be
        !           535: reported by a single call to the character data handler.  Expat, like
        !           536: many other XML parsers, reports such data as a sequence of calls;
        !           537: there's no way to know when the end of the sequence is reached until a
        !           538: different callback is made.  A buffer referenced by the user data
        !           539: structure proves both an effective and convenient place to accumulate
        !           540: character data.</p>
        !           541: 
        !           542: <!-- XXX example needed here -->
        !           543: 
        !           544: 
        !           545: <h3>XML Version</h3>
        !           546: 
        !           547: <p>Expat is an XML 1.0 parser, and as such never complains based on
        !           548: the value of the <code>version</code> pseudo-attribute in the XML
        !           549: declaration, if present.</p>
        !           550: 
        !           551: <p>If an application needs to check the version number (to support
        !           552: alternate processing), it should use the <code><a href=
        !           553: "#XML_SetXmlDeclHandler" >XML_SetXmlDeclHandler</a></code> function to
        !           554: set a handler that uses the information in the XML declaration to
        !           555: determine what to do.  This example shows how to check that only a
        !           556: version number of <code>"1.0"</code> is accepted:</p>
        !           557: 
        !           558: <pre class="eg">
        !           559: static int wrong_version;
        !           560: static XML_Parser parser;
        !           561: 
        !           562: static void XMLCALL
        !           563: xmldecl_handler(void            *userData,
        !           564:                 const XML_Char  *version,
        !           565:                 const XML_Char  *encoding,
        !           566:                 int              standalone)
        !           567: {
        !           568:   static const XML_Char Version_1_0[] = {'1', '.', '0', 0};
        !           569: 
        !           570:   int i;
        !           571: 
        !           572:   for (i = 0; i &lt; (sizeof(Version_1_0) / sizeof(Version_1_0[0])); ++i) {
        !           573:     if (version[i] != Version_1_0[i]) {
        !           574:       wrong_version = 1;
        !           575:       /* also clear all other handlers: */
        !           576:       XML_SetCharacterDataHandler(parser, NULL);
        !           577:       ...
        !           578:       return;
        !           579:     }
        !           580:   }
        !           581:   ...
        !           582: }
        !           583: </pre>
        !           584: 
        !           585: <h3>Namespace Processing</h3>
        !           586: 
        !           587: <p>When the parser is created using the <code><a href=
        !           588: "#XML_ParserCreateNS" >XML_ParserCreateNS</a></code>, function, Expat
        !           589: performs namespace processing. Under namespace processing, Expat
        !           590: consumes <code>xmlns</code> and <code>xmlns:...</code> attributes,
        !           591: which declare namespaces for the scope of the element in which they
        !           592: occur. This means that your start handler will not see these
        !           593: attributes.  Your application can still be informed of these
        !           594: declarations by setting namespace declaration handlers with <a href=
        !           595: "#XML_SetNamespaceDeclHandler"
        !           596: ><code>XML_SetNamespaceDeclHandler</code></a>.</p>
        !           597: 
        !           598: <p>Element type and attribute names that belong to a given namespace
        !           599: are passed to the appropriate handler in expanded form. By default
        !           600: this expanded form is a concatenation of the namespace URI, the
        !           601: separator character (which is the 2nd argument to <code><a href=
        !           602: "#XML_ParserCreateNS" >XML_ParserCreateNS</a></code>), and the local
        !           603: name (i.e. the part after the colon). Names with undeclared prefixes
        !           604: are not well-formed when namespace processing is enabled, and will
        !           605: trigger an error. Unprefixed attribute names are never expanded,
        !           606: and unprefixed element names are only expanded when they are in the
        !           607: scope of a default namespace.</p>
        !           608: 
        !           609: <p>However if <code><a href= "#XML_SetReturnNSTriplet"
        !           610: >XML_SetReturnNSTriplet</a></code> has been called with a non-zero
        !           611: <code>do_nst</code> parameter, then the expanded form for names with
        !           612: an explicit prefix is a concatenation of: URI, separator, local name,
        !           613: separator, prefix.</p>
        !           614: 
        !           615: <p>You can set handlers for the start of a namespace declaration and
        !           616: for the end of a scope of a declaration with the <code><a href=
        !           617: "#XML_SetNamespaceDeclHandler" >XML_SetNamespaceDeclHandler</a></code>
        !           618: function.  The StartNamespaceDeclHandler is called prior to the start
        !           619: tag handler and the EndNamespaceDeclHandler is called after the
        !           620: corresponding end tag that ends the namespace's scope.  The namespace
        !           621: start handler gets passed the prefix and URI for the namespace.  For a
        !           622: default namespace declaration (xmlns='...'), the prefix will be null.
        !           623: The URI will be null for the case where the default namespace is being
        !           624: unset.  The namespace end handler just gets the prefix for the closing
        !           625: scope.</p>
        !           626: 
        !           627: <p>These handlers are called for each declaration. So if, for
        !           628: instance, a start tag had three namespace declarations, then the
        !           629: StartNamespaceDeclHandler would be called three times before the start
        !           630: tag handler is called, once for each declaration.</p>
        !           631: 
        !           632: <h3>Character Encodings</h3>
        !           633: 
        !           634: <p>While XML is based on Unicode, and every XML processor is required
        !           635: to recognized UTF-8 and UTF-16 (1 and 2 byte encodings of Unicode),
        !           636: other encodings may be declared in XML documents or entities. For the
        !           637: main document, an XML declaration may contain an encoding
        !           638: declaration:</p>
        !           639: <pre>
        !           640: &lt;?xml version="1.0" encoding="ISO-8859-2"?&gt;
        !           641: </pre>
        !           642: 
        !           643: <p>External parsed entities may begin with a text declaration, which
        !           644: looks like an XML declaration with just an encoding declaration:</p>
        !           645: <pre>
        !           646: &lt;?xml encoding="Big5"?&gt;
        !           647: </pre>
        !           648: 
        !           649: <p>With Expat, you may also specify an encoding at the time of
        !           650: creating a parser. This is useful when the encoding information may
        !           651: come from a source outside the document itself (like a higher level
        !           652: protocol.)</p>
        !           653: 
        !           654: <p><a name="builtin_encodings"></a>There are four built-in encodings
        !           655: in Expat:</p>
        !           656: <ul>
        !           657: <li>UTF-8</li>
        !           658: <li>UTF-16</li>
        !           659: <li>ISO-8859-1</li>
        !           660: <li>US-ASCII</li>
        !           661: </ul>
        !           662: 
        !           663: <p>Anything else discovered in an encoding declaration or in the
        !           664: protocol encoding specified in the parser constructor, triggers a call
        !           665: to the <code>UnknownEncodingHandler</code>. This handler gets passed
        !           666: the encoding name and a pointer to an <code>XML_Encoding</code> data
        !           667: structure. Your handler must fill in this structure and return
        !           668: <code>XML_STATUS_OK</code> if it knows how to deal with the
        !           669: encoding. Otherwise the handler should return
        !           670: <code>XML_STATUS_ERROR</code>.  The handler also gets passed a pointer
        !           671: to an optional application data structure that you may indicate when
        !           672: you set the handler.</p>
        !           673: 
        !           674: <p>Expat places restrictions on character encodings that it can
        !           675: support by filling in the <code>XML_Encoding</code> structure.
        !           676: include file:</p>
        !           677: <ol>
        !           678: <li>Every ASCII character that can appear in a well-formed XML document
        !           679: must be represented by a single byte, and that byte must correspond to
        !           680: it's ASCII encoding (except for the characters $@\^'{}~)</li>
        !           681: <li>Characters must be encoded in 4 bytes or less.</li>
        !           682: <li>All characters encoded must have Unicode scalar values less than or
        !           683: equal to 65535 (0xFFFF)<em>This does not apply to the built-in support
        !           684: for UTF-16 and UTF-8</em></li>
        !           685: <li>No character may be encoded by more that one distinct sequence of
        !           686: bytes</li>
        !           687: </ol>
        !           688: 
        !           689: <p><code>XML_Encoding</code> contains an array of integers that
        !           690: correspond to the 1st byte of an encoding sequence. If the value in
        !           691: the array for a byte is zero or positive, then the byte is a single
        !           692: byte encoding that encodes the Unicode scalar value contained in the
        !           693: array. A -1 in this array indicates a malformed byte. If the value is
        !           694: -2, -3, or -4, then the byte is the beginning of a 2, 3, or 4 byte
        !           695: sequence respectively. Multi-byte sequences are sent to the convert
        !           696: function pointed at in the <code>XML_Encoding</code> structure. This
        !           697: function should return the Unicode scalar value for the sequence or -1
        !           698: if the sequence is malformed.</p>
        !           699: 
        !           700: <p>One pitfall that novice Expat users are likely to fall into is that
        !           701: although Expat may accept input in various encodings, the strings that
        !           702: it passes to the handlers are always encoded in UTF-8 or UTF-16
        !           703: (depending on how Expat was compiled). Your application is responsible
        !           704: for any translation of these strings into other encodings.</p>
        !           705: 
        !           706: <h3>Handling External Entity References</h3>
        !           707: 
        !           708: <p>Expat does not read or parse external entities directly. Note that
        !           709: any external DTD is a special case of an external entity.  If you've
        !           710: set no <code>ExternalEntityRefHandler</code>, then external entity
        !           711: references are silently ignored. Otherwise, it calls your handler with
        !           712: the information needed to read and parse the external entity.</p>
        !           713: 
        !           714: <p>Your handler isn't actually responsible for parsing the entity, but
        !           715: it is responsible for creating a subsidiary parser with <code><a href=
        !           716: "#XML_ExternalEntityParserCreate"
        !           717: >XML_ExternalEntityParserCreate</a></code> that will do the job. This
        !           718: returns an instance of <code>XML_Parser</code> that has handlers and
        !           719: other data structures initialized from the parent parser. You may then
        !           720: use <code><a href= "#XML_Parse" >XML_Parse</a></code> or <code><a
        !           721: href= "#XML_ParseBuffer">XML_ParseBuffer</a></code> calls against this
        !           722: parser.  Since external entities my refer to other external entities,
        !           723: your handler should be prepared to be called recursively.</p>
        !           724: 
        !           725: <h3>Parsing DTDs</h3>
        !           726: 
        !           727: <p>In order to parse parameter entities, before starting the parse,
        !           728: you must call <code><a href= "#XML_SetParamEntityParsing"
        !           729: >XML_SetParamEntityParsing</a></code> with one of the following
        !           730: arguments:</p>
        !           731: <dl>
        !           732: <dt><code>XML_PARAM_ENTITY_PARSING_NEVER</code></dt>
        !           733: <dd>Don't parse parameter entities or the external subset</dd>
        !           734: <dt><code>XML_PARAM_ENTITY_PARSING_UNLESS_STANDALONE</code></dt>
        !           735: <dd>Parse parameter entites and the external subset unless
        !           736: <code>standalone</code> was set to "yes" in the XML declaration.</dd>
        !           737: <dt><code>XML_PARAM_ENTITY_PARSING_ALWAYS</code></dt>
        !           738: <dd>Always parse parameter entities and the external subset</dd>
        !           739: </dl>
        !           740: 
        !           741: <p>In order to read an external DTD, you also have to set an external
        !           742: entity reference handler as described above.</p>
        !           743: 
        !           744: <h3 id="stop-resume">Temporarily Stopping Parsing</h3>
        !           745: 
        !           746: <p>Expat 1.95.8 introduces a new feature: its now possible to stop
        !           747: parsing temporarily from within a handler function, even if more data
        !           748: has already been passed into the parser.  Applications for this
        !           749: include</p>
        !           750: 
        !           751: <ul>
        !           752:   <li>Supporting the <a href= "http://www.w3.org/TR/xinclude/"
        !           753:   >XInclude</a> specification.</li>
        !           754: 
        !           755:   <li>Delaying further processing until additional information is
        !           756:   available from some other source.</li>
        !           757: 
        !           758:   <li>Adjusting processor load as task priorities shift within an
        !           759:   application.</li>
        !           760: 
        !           761:   <li>Stopping parsing completely (simply free or reset the parser
        !           762:   instead of resuming in the outer parsing loop).  This can be useful
        !           763:   if a application-domain error is found in the XML being parsed or if
        !           764:   the result of the parse is determined not to be useful after
        !           765:   all.</li>
        !           766: </ul>
        !           767: 
        !           768: <p>To take advantage of this feature, the main parsing loop of an
        !           769: application needs to support this specifically.  It cannot be
        !           770: supported with a parsing loop compatible with Expat 1.95.7 or
        !           771: earlier (though existing loops will continue to work without
        !           772: supporting the stop/resume feature).</p>
        !           773: 
        !           774: <p>An application that uses this feature for a single parser will have
        !           775: the rough structure (in pseudo-code):</p>
        !           776: 
        !           777: <pre class="pseudocode">
        !           778: fd = open_input()
        !           779: p = create_parser()
        !           780: 
        !           781: if parse_xml(p, fd) {
        !           782:   /* suspended */
        !           783: 
        !           784:   int suspended = 1;
        !           785: 
        !           786:   while (suspended) {
        !           787:     do_something_else()
        !           788:     if ready_to_resume() {
        !           789:       suspended = continue_parsing(p, fd);
        !           790:     }
        !           791:   }
        !           792: }
        !           793: </pre>
        !           794: 
        !           795: <p>An application that may resume any of several parsers based on
        !           796: input (either from the XML being parsed or some other source) will
        !           797: certainly have more interesting control structures.</p>
        !           798: 
        !           799: <p>This C function could be used for the <code>parse_xml</code>
        !           800: function mentioned in the pseudo-code above:</p>
        !           801: 
        !           802: <pre class="eg">
        !           803: #define BUFF_SIZE 10240
        !           804: 
        !           805: /* Parse a document from the open file descriptor 'fd' until the parse
        !           806:    is complete (the document has been completely parsed, or there's
        !           807:    been an error), or the parse is stopped.  Return non-zero when
        !           808:    the parse is merely suspended.
        !           809: */
        !           810: int
        !           811: parse_xml(XML_Parser p, int fd)
        !           812: {
        !           813:   for (;;) {
        !           814:     int last_chunk;
        !           815:     int bytes_read;
        !           816:     enum XML_Status status;
        !           817: 
        !           818:     void *buff = XML_GetBuffer(p, BUFF_SIZE);
        !           819:     if (buff == NULL) {
        !           820:       /* handle error... */
        !           821:       return 0;
        !           822:     }
        !           823:     bytes_read = read(fd, buff, BUFF_SIZE);
        !           824:     if (bytes_read &lt; 0) {
        !           825:       /* handle error... */
        !           826:       return 0;
        !           827:     }
        !           828:     status = XML_ParseBuffer(p, bytes_read, bytes_read == 0);
        !           829:     switch (status) {
        !           830:       case XML_STATUS_ERROR:
        !           831:         /* handle error... */
        !           832:         return 0;
        !           833:       case XML_STATUS_SUSPENDED:
        !           834:         return 1;
        !           835:     }
        !           836:     if (bytes_read == 0)
        !           837:       return 0;
        !           838:   }
        !           839: }
        !           840: </pre>
        !           841: 
        !           842: <p>The corresponding <code>continue_parsing</code> function is
        !           843: somewhat simpler, since it only need deal with the return code from
        !           844: <code><a href= "#XML_ResumeParser">XML_ResumeParser</a></code>; it can
        !           845: delegate the input handling to the <code>parse_xml</code>
        !           846: function:</p>
        !           847: 
        !           848: <pre class="eg">
        !           849: /* Continue parsing a document which had been suspended.  The 'p' and
        !           850:    'fd' arguments are the same as passed to parse_xml().  Return
        !           851:    non-zero when the parse is suspended.
        !           852: */
        !           853: int
        !           854: continue_parsing(XML_Parser p, int fd)
        !           855: {
        !           856:   enum XML_Status status = XML_ResumeParser(p);
        !           857:   switch (status) {
        !           858:     case XML_STATUS_ERROR:
        !           859:       /* handle error... */
        !           860:       return 0;
        !           861:     case XML_ERROR_NOT_SUSPENDED:
        !           862:       /* handle error... */
        !           863:       return 0;.
        !           864:     case XML_STATUS_SUSPENDED:
        !           865:       return 1;
        !           866:   }
        !           867:   return parse_xml(p, fd);
        !           868: }
        !           869: </pre>
        !           870: 
        !           871: <p>Now that we've seen what a mess the top-level parsing loop can
        !           872: become, what have we gained?  Very simply, we can now use the <code><a
        !           873: href= "#XML_StopParser" >XML_StopParser</a></code> function to stop
        !           874: parsing, without having to go to great lengths to avoid additional
        !           875: processing that we're expecting to ignore.  As a bonus, we get to stop
        !           876: parsing <em>temporarily</em>, and come back to it when we're
        !           877: ready.</p>
        !           878: 
        !           879: <p>To stop parsing from a handler function, use the <code><a href=
        !           880: "#XML_StopParser" >XML_StopParser</a></code> function.  This function
        !           881: takes two arguments; the parser being stopped and a flag indicating
        !           882: whether the parse can be resumed in the future.</p>
        !           883: 
        !           884: <!-- XXX really need more here -->
        !           885: 
        !           886: 
        !           887: <hr />
        !           888: <!-- ================================================================ -->
        !           889: 
        !           890: <h2><a name="reference">Expat Reference</a></h2>
        !           891: 
        !           892: <h3><a name="creation">Parser Creation</a></h3>
        !           893: 
        !           894: <pre class="fcndec" id="XML_ParserCreate">
        !           895: XML_Parser XMLCALL
        !           896: XML_ParserCreate(const XML_Char *encoding);
        !           897: </pre>
        !           898: <div class="fcndef">
        !           899: Construct a new parser. If encoding is non-null, it specifies a
        !           900: character encoding to use for the document. This overrides the document
        !           901: encoding declaration. There are four built-in encodings:
        !           902: <ul>
        !           903: <li>US-ASCII</li>
        !           904: <li>UTF-8</li>
        !           905: <li>UTF-16</li>
        !           906: <li>ISO-8859-1</li>
        !           907: </ul>
        !           908: Any other value will invoke a call to the UnknownEncodingHandler.
        !           909: </div>
        !           910: 
        !           911: <pre class="fcndec" id="XML_ParserCreateNS">
        !           912: XML_Parser XMLCALL
        !           913: XML_ParserCreateNS(const XML_Char *encoding,
        !           914:                    XML_Char sep);
        !           915: </pre>
        !           916: <div class="fcndef">
        !           917: Constructs a new parser that has namespace processing in effect. Namespace
        !           918: expanded element names and attribute names are returned as a concatenation
        !           919: of the namespace URI, <em>sep</em>, and the local part of the name. This
        !           920: means that you should pick a character for <em>sep</em> that can't be
        !           921: part of a legal URI. There is a special case when <em>sep</em> is the null
        !           922: character <code>'\0'</code>: the namespace URI and the local part will be
        !           923: concatenated without any separator - this is intended to support RDF processors.
        !           924: It is a programming error to use the null separator with 
        !           925: <a href= "#XML_SetReturnNSTriplet">namespace triplets</a>.</div>
        !           926: 
        !           927: <pre class="fcndec" id="XML_ParserCreate_MM">
        !           928: XML_Parser XMLCALL
        !           929: XML_ParserCreate_MM(const XML_Char *encoding,
        !           930:                     const XML_Memory_Handling_Suite *ms,
        !           931:                    const XML_Char *sep);
        !           932: </pre>
        !           933: <pre class="signature">
        !           934: typedef struct {
        !           935:   void *(XMLCALL *malloc_fcn)(size_t size);
        !           936:   void *(XMLCALL *realloc_fcn)(void *ptr, size_t size);
        !           937:   void (XMLCALL *free_fcn)(void *ptr);
        !           938: } XML_Memory_Handling_Suite;
        !           939: </pre>
        !           940: <div class="fcndef">
        !           941: <p>Construct a new parser using the suite of memory handling functions
        !           942: specified in <code>ms</code>. If <code>ms</code> is NULL, then use the
        !           943: standard set of memory management functions. If <code>sep</code> is
        !           944: non NULL, then namespace processing is enabled in the created parser
        !           945: and the character pointed at by sep is used as the separator between
        !           946: the namespace URI and the local part of the name.</p>
        !           947: </div>
        !           948: 
        !           949: <pre class="fcndec" id="XML_ExternalEntityParserCreate">
        !           950: XML_Parser XMLCALL
        !           951: XML_ExternalEntityParserCreate(XML_Parser p,
        !           952:                                const XML_Char *context,
        !           953:                                const XML_Char *encoding);
        !           954: </pre>
        !           955: <div class="fcndef">
        !           956: Construct a new <code>XML_Parser</code> object for parsing an external
        !           957: general entity. Context is the context argument passed in a call to a
        !           958: ExternalEntityRefHandler. Other state information such as handlers,
        !           959: user data, namespace processing is inherited from the parser passed as
        !           960: the 1st argument. So you shouldn't need to call any of the behavior
        !           961: changing functions on this parser (unless you want it to act
        !           962: differently than the parent parser).
        !           963: </div>
        !           964: 
        !           965: <pre class="fcndec" id="XML_ParserFree">
        !           966: void XMLCALL
        !           967: XML_ParserFree(XML_Parser p);
        !           968: </pre>
        !           969: <div class="fcndef">
        !           970: Free memory used by the parser. Your application is responsible for
        !           971: freeing any memory associated with <a href="#userdata">user data</a>.
        !           972: </div>
        !           973: 
        !           974: <pre class="fcndec" id="XML_ParserReset">
        !           975: XML_Bool XMLCALL
        !           976: XML_ParserReset(XML_Parser p,
        !           977:                 const XML_Char *encoding);
        !           978: </pre>
        !           979: <div class="fcndef">
        !           980: Clean up the memory structures maintained by the parser so that it may
        !           981: be used again.  After this has been called, <code>parser</code> is
        !           982: ready to start parsing a new document.  All handlers are cleared from
        !           983: the parser, except for the unknownEncodingHandler.  The parser's external
        !           984: state is re-initialized except for the values of ns and ns_triplets.
        !           985: This function may not be used on a parser created using <code><a href=
        !           986: "#XML_ExternalEntityParserCreate" >XML_ExternalEntityParserCreate</a
        !           987: ></code>; it will return <code>XML_FALSE</code> in that case.  Returns
        !           988: <code>XML_TRUE</code> on success.  Your application is responsible for
        !           989: dealing with any memory associated with <a href="#userdata">user data</a>.
        !           990: </div>
        !           991: 
        !           992: <h3><a name="parsing">Parsing</a></h3>
        !           993: 
        !           994: <p>To state the obvious: the three parsing functions <code><a href=
        !           995: "#XML_Parse" >XML_Parse</a></code>, <code><a href= "#XML_ParseBuffer">
        !           996: XML_ParseBuffer</a></code> and <code><a href= "#XML_GetBuffer">
        !           997: XML_GetBuffer</a></code> must not be called from within a handler
        !           998: unless they operate on a separate parser instance, that is, one that
        !           999: did not call the handler. For example, it is OK to call the parsing
        !          1000: functions from within an <code>XML_ExternalEntityRefHandler</code>,
        !          1001: if they apply to the parser created by
        !          1002: <code><a href= "#XML_ExternalEntityParserCreate"
        !          1003: >XML_ExternalEntityParserCreate</a></code>.</p>
        !          1004: 
        !          1005: <p>Note: the <code>len</code> argument passed to these functions
        !          1006: should be considerably less than the maximum value for an integer,
        !          1007: as it could create an integer overflow situation if the added
        !          1008: lengths of a buffer and the unprocessed portion of the previous buffer
        !          1009: exceed the maximum integer value. Input data at the end of a buffer
        !          1010: will remain unprocessed if it is part of an XML token for which the
        !          1011: end is not part of that buffer.</p>
        !          1012: 
        !          1013: <pre class="fcndec" id="XML_Parse">
        !          1014: enum XML_Status XMLCALL
        !          1015: XML_Parse(XML_Parser p,
        !          1016:           const char *s,
        !          1017:           int len,
        !          1018:           int isFinal);
        !          1019: </pre>
        !          1020: <pre class="signature">
        !          1021: enum XML_Status {
        !          1022:   XML_STATUS_ERROR = 0,
        !          1023:   XML_STATUS_OK = 1
        !          1024: };
        !          1025: </pre>
        !          1026: <div class="fcndef">
        !          1027: Parse some more of the document. The string <code>s</code> is a buffer
        !          1028: containing part (or perhaps all) of the document. The number of bytes of s
        !          1029: that are part of the document is indicated by <code>len</code>. This means
        !          1030: that <code>s</code> doesn't have to be null terminated. It also means that
        !          1031: if <code>len</code> is larger than the number of bytes in the block of
        !          1032: memory that <code>s</code> points at, then a memory fault is likely. The
        !          1033: <code>isFinal</code> parameter informs the parser that this is the last
        !          1034: piece of the document. Frequently, the last piece is empty (i.e.
        !          1035: <code>len</code> is zero.)
        !          1036: If a parse error occurred, it returns <code>XML_STATUS_ERROR</code>.
        !          1037: Otherwise it returns <code>XML_STATUS_OK</code> value.
        !          1038: </div>
        !          1039: 
        !          1040: <pre class="fcndec" id="XML_ParseBuffer">
        !          1041: enum XML_Status XMLCALL
        !          1042: XML_ParseBuffer(XML_Parser p,
        !          1043:                 int len,
        !          1044:                 int isFinal);
        !          1045: </pre>
        !          1046: <div class="fcndef">
        !          1047: This is just like <code><a href= "#XML_Parse" >XML_Parse</a></code>,
        !          1048: except in this case Expat provides the buffer.  By obtaining the
        !          1049: buffer from Expat with the <code><a href= "#XML_GetBuffer"
        !          1050: >XML_GetBuffer</a></code> function, the application can avoid double
        !          1051: copying of the input.
        !          1052: </div>
        !          1053: 
        !          1054: <pre class="fcndec" id="XML_GetBuffer">
        !          1055: void * XMLCALL
        !          1056: XML_GetBuffer(XML_Parser p,
        !          1057:               int len);
        !          1058: </pre>
        !          1059: <div class="fcndef">
        !          1060: Obtain a buffer of size <code>len</code> to read a piece of the document
        !          1061: into. A NULL value is returned if Expat can't allocate enough memory for
        !          1062: this buffer. This has to be called prior to every call to
        !          1063: <code><a href= "#XML_ParseBuffer" >XML_ParseBuffer</a></code>. A
        !          1064: typical use would look like this:
        !          1065: 
        !          1066: <pre class="eg">
        !          1067: for (;;) {
        !          1068:   int bytes_read;
        !          1069:   void *buff = XML_GetBuffer(p, BUFF_SIZE);
        !          1070:   if (buff == NULL) {
        !          1071:     /* handle error */
        !          1072:   }
        !          1073: 
        !          1074:   bytes_read = read(docfd, buff, BUFF_SIZE);
        !          1075:   if (bytes_read &lt; 0) {
        !          1076:     /* handle error */
        !          1077:   }
        !          1078: 
        !          1079:   if (! XML_ParseBuffer(p, bytes_read, bytes_read == 0)) {
        !          1080:     /* handle parse error */
        !          1081:   }
        !          1082: 
        !          1083:   if (bytes_read == 0)
        !          1084:     break;
        !          1085: }
        !          1086: </pre>
        !          1087: </div>
        !          1088: 
        !          1089: <pre class="fcndec" id="XML_StopParser">
        !          1090: enum XML_Status XMLCALL
        !          1091: XML_StopParser(XML_Parser p,
        !          1092:                XML_Bool resumable);
        !          1093: </pre>
        !          1094: <div class="fcndef">
        !          1095: 
        !          1096: <p>Stops parsing, causing <code><a href= "#XML_Parse"
        !          1097: >XML_Parse</a></code> or <code><a href= "#XML_ParseBuffer"
        !          1098: >XML_ParseBuffer</a></code> to return.  Must be called from within a
        !          1099: call-back handler, except when aborting (when <code>resumable</code>
        !          1100: is <code>XML_FALSE</code>) an already suspended parser.  Some
        !          1101: call-backs may still follow because they would otherwise get
        !          1102: lost, including
        !          1103: <ul>
        !          1104:   <li> the end element handler for empty elements when stopped in the
        !          1105:        start element handler,</li>
        !          1106:   <li> the end namespace declaration handler when stopped in the end
        !          1107:        element handler,</li>
        !          1108:   <li> the character data handler when stopped in the character data handler
        !          1109:        while making multiple call-backs on a contiguous chunk of characters,</li>
        !          1110: </ul>
        !          1111: and possibly others.</p>
        !          1112: 
        !          1113: <p>This can be called from most handlers, including DTD related
        !          1114: call-backs, except when parsing an external parameter entity and
        !          1115: <code>resumable</code> is <code>XML_TRUE</code>.  Returns
        !          1116: <code>XML_STATUS_OK</code> when successful,
        !          1117: <code>XML_STATUS_ERROR</code> otherwise.  The possible error codes
        !          1118: are:</p>
        !          1119: <dl>
        !          1120:   <dt><code>XML_ERROR_SUSPENDED</code></dt>
        !          1121:   <dd>when suspending an already suspended parser.</dd>
        !          1122:   <dt><code>XML_ERROR_FINISHED</code></dt>
        !          1123:   <dd>when the parser has already finished.</dd>
        !          1124:   <dt><code>XML_ERROR_SUSPEND_PE</code></dt>
        !          1125:   <dd>when suspending while parsing an external PE.</dd>
        !          1126: </dl>
        !          1127: 
        !          1128: <p>Since the stop/resume feature requires application support in the
        !          1129: outer parsing loop, it is an error to call this function for a parser
        !          1130: not being handled appropriately; see <a href= "#stop-resume"
        !          1131: >Temporarily Stopping Parsing</a> for more information.</p>
        !          1132: 
        !          1133: <p>When <code>resumable</code> is <code>XML_TRUE</code> then parsing
        !          1134: is <em>suspended</em>, that is, <code><a href= "#XML_Parse"
        !          1135: >XML_Parse</a></code> and <code><a href= "#XML_ParseBuffer"
        !          1136: >XML_ParseBuffer</a></code> return <code>XML_STATUS_SUSPENDED</code>.
        !          1137: Otherwise, parsing is <em>aborted</em>, that is, <code><a href=
        !          1138: "#XML_Parse" >XML_Parse</a></code> and <code><a href=
        !          1139: "#XML_ParseBuffer" >XML_ParseBuffer</a></code> return
        !          1140: <code>XML_STATUS_ERROR</code> with error code
        !          1141: <code>XML_ERROR_ABORTED</code>.</p>
        !          1142: 
        !          1143: <p><strong>Note:</strong>
        !          1144: This will be applied to the current parser instance only, that is, if
        !          1145: there is a parent parser then it will continue parsing when the
        !          1146: external entity reference handler returns.  It is up to the
        !          1147: implementation of that handler to call <code><a href=
        !          1148: "#XML_StopParser" >XML_StopParser</a></code> on the parent parser
        !          1149: (recursively), if one wants to stop parsing altogether.</p>
        !          1150: 
        !          1151: <p>When suspended, parsing can be resumed by calling <code><a href=
        !          1152: "#XML_ResumeParser" >XML_ResumeParser</a></code>.</p>
        !          1153: 
        !          1154: <p>New in Expat 1.95.8.</p>
        !          1155: </div>
        !          1156: 
        !          1157: <pre class="fcndec" id="XML_ResumeParser">
        !          1158: enum XML_Status XMLCALL
        !          1159: XML_ResumeParser(XML_Parser p);
        !          1160: </pre>
        !          1161: <div class="fcndef">
        !          1162: <p>Resumes parsing after it has been suspended with <code><a href=
        !          1163: "#XML_StopParser" >XML_StopParser</a></code>.  Must not be called from
        !          1164: within a handler call-back.  Returns same status codes as <code><a
        !          1165: href= "#XML_Parse">XML_Parse</a></code> or <code><a href=
        !          1166: "#XML_ParseBuffer" >XML_ParseBuffer</a></code>.  An additional error
        !          1167: code, <code>XML_ERROR_NOT_SUSPENDED</code>, will be returned if the
        !          1168: parser was not currently suspended.</p>
        !          1169: 
        !          1170: <p><strong>Note:</strong>
        !          1171: This must be called on the most deeply nested child parser instance
        !          1172: first, and on its parent parser only after the child parser has
        !          1173: finished, to be applied recursively until the document entity's parser
        !          1174: is restarted.  That is, the parent parser will not resume by itself
        !          1175: and it is up to the application to call <code><a href=
        !          1176: "#XML_ResumeParser" >XML_ResumeParser</a></code> on it at the
        !          1177: appropriate moment.</p>
        !          1178: 
        !          1179: <p>New in Expat 1.95.8.</p>
        !          1180: </div>
        !          1181: 
        !          1182: <pre class="fcndec" id="XML_GetParsingStatus">
        !          1183: void XMLCALL
        !          1184: XML_GetParsingStatus(XML_Parser p,
        !          1185:                      XML_ParsingStatus *status);
        !          1186: </pre>
        !          1187: <pre class="signature">
        !          1188: enum XML_Parsing {
        !          1189:   XML_INITIALIZED,
        !          1190:   XML_PARSING,
        !          1191:   XML_FINISHED,
        !          1192:   XML_SUSPENDED
        !          1193: };
        !          1194: 
        !          1195: typedef struct {
        !          1196:   enum XML_Parsing parsing;
        !          1197:   XML_Bool finalBuffer;
        !          1198: } XML_ParsingStatus;
        !          1199: </pre>
        !          1200: <div class="fcndef">
        !          1201: <p>Returns status of parser with respect to being initialized,
        !          1202: parsing, finished, or suspended, and whether the final buffer is being
        !          1203: processed.  The <code>status</code> parameter <em>must not</em> be
        !          1204: NULL.</p>
        !          1205: 
        !          1206: <p>New in Expat 1.95.8.</p>
        !          1207: </div>
        !          1208: 
        !          1209: 
        !          1210: <h3><a name="setting">Handler Setting</a></h3>
        !          1211: 
        !          1212: <p>Although handlers are typically set prior to parsing and left alone, an
        !          1213: application may choose to set or change the handler for a parsing event
        !          1214: while the parse is in progress. For instance, your application may choose
        !          1215: to ignore all text not descended from a <code>para</code> element. One
        !          1216: way it could do this is to set the character handler when a para start tag
        !          1217: is seen, and unset it for the corresponding end tag.</p>
        !          1218: 
        !          1219: <p>A handler may be <em>unset</em> by providing a NULL pointer to the
        !          1220: appropriate handler setter. None of the handler setting functions have
        !          1221: a return value.</p>
        !          1222: 
        !          1223: <p>Your handlers will be receiving strings in arrays of type
        !          1224: <code>XML_Char</code>. This type is conditionally defined in expat.h as
        !          1225: either <code>char</code>, <code>wchar_t</code> or <code>unsigned short</code>.
        !          1226: The former implies UTF-8 encoding, the latter two imply UTF-16 encoding.
        !          1227: Note that you'll receive them in this form independent of the original
        !          1228: encoding of the document.</p>
        !          1229: 
        !          1230: <div class="handler">
        !          1231: <pre class="setter" id="XML_SetStartElementHandler">
        !          1232: void XMLCALL
        !          1233: XML_SetStartElementHandler(XML_Parser p,
        !          1234:                            XML_StartElementHandler start);
        !          1235: </pre>
        !          1236: <pre class="signature">
        !          1237: typedef void
        !          1238: (XMLCALL *XML_StartElementHandler)(void *userData,
        !          1239:                                    const XML_Char *name,
        !          1240:                                    const XML_Char **atts);
        !          1241: </pre>
        !          1242: <p>Set handler for start (and empty) tags. Attributes are passed to the start
        !          1243: handler as a pointer to a vector of char pointers. Each attribute seen in
        !          1244: a start (or empty) tag occupies 2 consecutive places in this vector: the
        !          1245: attribute name followed by the attribute value. These pairs are terminated
        !          1246: by a null pointer.</p>
        !          1247: <p>Note that an empty tag generates a call to both start and end handlers
        !          1248: (in that order).</p>
        !          1249: </div>
        !          1250: 
        !          1251: <div class="handler">
        !          1252: <pre class="setter" id="XML_SetEndElementHandler">
        !          1253: void XMLCALL
        !          1254: XML_SetEndElementHandler(XML_Parser p,
        !          1255:                          XML_EndElementHandler);
        !          1256: </pre>
        !          1257: <pre class="signature">
        !          1258: typedef void
        !          1259: (XMLCALL *XML_EndElementHandler)(void *userData,
        !          1260:                                  const XML_Char *name);
        !          1261: </pre>
        !          1262: <p>Set handler for end (and empty) tags. As noted above, an empty tag
        !          1263: generates a call to both start and end handlers.</p>
        !          1264: </div>
        !          1265: 
        !          1266: <div class="handler">
        !          1267: <pre class="setter" id="XML_SetElementHandler">
        !          1268: void XMLCALL
        !          1269: XML_SetElementHandler(XML_Parser p,
        !          1270:                       XML_StartElementHandler start,
        !          1271:                       XML_EndElementHandler end);
        !          1272: </pre>
        !          1273: <p>Set handlers for start and end tags with one call.</p>
        !          1274: </div>
        !          1275: 
        !          1276: <div class="handler">
        !          1277: <pre class="setter" id="XML_SetCharacterDataHandler">
        !          1278: void XMLCALL
        !          1279: XML_SetCharacterDataHandler(XML_Parser p,
        !          1280:                             XML_CharacterDataHandler charhndl)
        !          1281: </pre>
        !          1282: <pre class="signature">
        !          1283: typedef void
        !          1284: (XMLCALL *XML_CharacterDataHandler)(void *userData,
        !          1285:                                     const XML_Char *s,
        !          1286:                                     int len);
        !          1287: </pre>
        !          1288: <p>Set a text handler. The string your handler receives
        !          1289: is <em>NOT nul-terminated</em>. You have to use the length argument
        !          1290: to deal with the end of the string. A single block of contiguous text
        !          1291: free of markup may still result in a sequence of calls to this handler.
        !          1292: In other words, if you're searching for a pattern in the text, it may
        !          1293: be split across calls to this handler. Note: Setting this handler to NULL
        !          1294: may <em>NOT immediately</em> terminate call-backs if the parser is currently
        !          1295: processing such a single block of contiguous markup-free text, as the parser
        !          1296: will continue calling back until the end of the block is reached.</p>
        !          1297: </div>
        !          1298: 
        !          1299: <div class="handler">
        !          1300: <pre class="setter" id="XML_SetProcessingInstructionHandler">
        !          1301: void XMLCALL
        !          1302: XML_SetProcessingInstructionHandler(XML_Parser p,
        !          1303:                                     XML_ProcessingInstructionHandler proc)
        !          1304: </pre>
        !          1305: <pre class="signature">
        !          1306: typedef void
        !          1307: (XMLCALL *XML_ProcessingInstructionHandler)(void *userData,
        !          1308:                                             const XML_Char *target,
        !          1309:                                             const XML_Char *data);
        !          1310: 
        !          1311: </pre>
        !          1312: <p>Set a handler for processing instructions. The target is the first word
        !          1313: in the processing instruction. The data is the rest of the characters in
        !          1314: it after skipping all whitespace after the initial word.</p>
        !          1315: </div>
        !          1316: 
        !          1317: <div class="handler">
        !          1318: <pre class="setter" id="XML_SetCommentHandler">
        !          1319: void XMLCALL
        !          1320: XML_SetCommentHandler(XML_Parser p,
        !          1321:                       XML_CommentHandler cmnt)
        !          1322: </pre>
        !          1323: <pre class="signature">
        !          1324: typedef void
        !          1325: (XMLCALL *XML_CommentHandler)(void *userData,
        !          1326:                               const XML_Char *data);
        !          1327: </pre>
        !          1328: <p>Set a handler for comments. The data is all text inside the comment
        !          1329: delimiters.</p>
        !          1330: </div>
        !          1331: 
        !          1332: <div class="handler">
        !          1333: <pre class="setter" id="XML_SetStartCdataSectionHandler">
        !          1334: void XMLCALL
        !          1335: XML_SetStartCdataSectionHandler(XML_Parser p,
        !          1336:                                 XML_StartCdataSectionHandler start);
        !          1337: </pre>
        !          1338: <pre class="signature">
        !          1339: typedef void
        !          1340: (XMLCALL *XML_StartCdataSectionHandler)(void *userData);
        !          1341: </pre>
        !          1342: <p>Set a handler that gets called at the beginning of a CDATA section.</p>
        !          1343: </div>
        !          1344: 
        !          1345: <div class="handler">
        !          1346: <pre class="setter" id="XML_SetEndCdataSectionHandler">
        !          1347: void XMLCALL
        !          1348: XML_SetEndCdataSectionHandler(XML_Parser p,
        !          1349:                               XML_EndCdataSectionHandler end);
        !          1350: </pre>
        !          1351: <pre class="signature">
        !          1352: typedef void
        !          1353: (XMLCALL *XML_EndCdataSectionHandler)(void *userData);
        !          1354: </pre>
        !          1355: <p>Set a handler that gets called at the end of a CDATA section.</p>
        !          1356: </div>
        !          1357: 
        !          1358: <div class="handler">
        !          1359: <pre class="setter" id="XML_SetCdataSectionHandler">
        !          1360: void XMLCALL
        !          1361: XML_SetCdataSectionHandler(XML_Parser p,
        !          1362:                            XML_StartCdataSectionHandler start,
        !          1363:                            XML_EndCdataSectionHandler end)
        !          1364: </pre>
        !          1365: <p>Sets both CDATA section handlers with one call.</p>
        !          1366: </div>
        !          1367: 
        !          1368: <div class="handler">
        !          1369: <pre class="setter" id="XML_SetDefaultHandler">
        !          1370: void XMLCALL
        !          1371: XML_SetDefaultHandler(XML_Parser p,
        !          1372:                       XML_DefaultHandler hndl)
        !          1373: </pre>
        !          1374: <pre class="signature">
        !          1375: typedef void
        !          1376: (XMLCALL *XML_DefaultHandler)(void *userData,
        !          1377:                               const XML_Char *s,
        !          1378:                               int len);
        !          1379: </pre>
        !          1380: 
        !          1381: <p>Sets a handler for any characters in the document which wouldn't
        !          1382: otherwise be handled. This includes both data for which no handlers
        !          1383: can be set (like some kinds of DTD declarations) and data which could
        !          1384: be reported but which currently has no handler set.  The characters
        !          1385: are passed exactly as they were present in the XML document except
        !          1386: that they will be encoded in UTF-8 or UTF-16. Line boundaries are not
        !          1387: normalized. Note that a byte order mark character is not passed to the
        !          1388: default handler. There are no guarantees about how characters are
        !          1389: divided between calls to the default handler: for example, a comment
        !          1390: might be split between multiple calls.  Setting the handler with
        !          1391: this call has the side effect of turning off expansion of references
        !          1392: to internally defined general entities. Instead these references are
        !          1393: passed to the default handler.</p>
        !          1394: 
        !          1395: <p>See also <code><a
        !          1396: href="#XML_DefaultCurrent">XML_DefaultCurrent</a></code>.</p>
        !          1397: </div>
        !          1398: 
        !          1399: <div class="handler">
        !          1400: <pre class="setter" id="XML_SetDefaultHandlerExpand">
        !          1401: void XMLCALL
        !          1402: XML_SetDefaultHandlerExpand(XML_Parser p,
        !          1403:                             XML_DefaultHandler hndl)
        !          1404: </pre>
        !          1405: <pre class="signature">
        !          1406: typedef void
        !          1407: (XMLCALL *XML_DefaultHandler)(void *userData,
        !          1408:                               const XML_Char *s,
        !          1409:                               int len);
        !          1410: </pre>
        !          1411: <p>This sets a default handler, but doesn't inhibit the expansion of
        !          1412: internal entity references.  The entity reference will not be passed
        !          1413: to the default handler.</p>
        !          1414: 
        !          1415: <p>See also <code><a
        !          1416: href="#XML_DefaultCurrent">XML_DefaultCurrent</a></code>.</p>
        !          1417: </div>
        !          1418: 
        !          1419: <div class="handler">
        !          1420: <pre class="setter" id="XML_SetExternalEntityRefHandler">
        !          1421: void XMLCALL
        !          1422: XML_SetExternalEntityRefHandler(XML_Parser p,
        !          1423:                                 XML_ExternalEntityRefHandler hndl)
        !          1424: </pre>
        !          1425: <pre class="signature">
        !          1426: typedef int
        !          1427: (XMLCALL *XML_ExternalEntityRefHandler)(XML_Parser p,
        !          1428:                                         const XML_Char *context,
        !          1429:                                         const XML_Char *base,
        !          1430:                                         const XML_Char *systemId,
        !          1431:                                         const XML_Char *publicId);
        !          1432: </pre>
        !          1433: <p>Set an external entity reference handler. This handler is also
        !          1434: called for processing an external DTD subset if parameter entity parsing
        !          1435: is in effect. (See <a href="#XML_SetParamEntityParsing">
        !          1436: <code>XML_SetParamEntityParsing</code></a>.)</p>
        !          1437: 
        !          1438: <p>The <code>context</code> parameter specifies the parsing context in
        !          1439: the format expected by the <code>context</code> argument to <code><a
        !          1440: href="#XML_ExternalEntityParserCreate"
        !          1441: >XML_ExternalEntityParserCreate</a></code>.  <code>code</code> is
        !          1442: valid only until the handler returns, so if the referenced entity is
        !          1443: to be parsed later, it must be copied.  <code>context</code> is NULL
        !          1444: only when the entity is a parameter entity, which is how one can
        !          1445: differentiate between general and parameter entities.</p>
        !          1446: 
        !          1447: <p>The <code>base</code> parameter is the base to use for relative
        !          1448: system identifiers.  It is set by <code><a
        !          1449: href="#XML_SetBase">XML_SetBase</a></code> and may be NULL. The
        !          1450: <code>publicId</code> parameter is the public id given in the entity
        !          1451: declaration and may be NULL.  <code>systemId</code> is the system
        !          1452: identifier specified in the entity declaration and is never NULL.</p>
        !          1453: 
        !          1454: <p>There are a couple of ways in which this handler differs from
        !          1455: others.  First, this handler returns a status indicator (an
        !          1456: integer). <code>XML_STATUS_OK</code> should be returned for successful
        !          1457: handling of the external entity reference.  Returning
        !          1458: <code>XML_STATUS_ERROR</code> indicates failure, and causes the
        !          1459: calling parser to return an
        !          1460: <code>XML_ERROR_EXTERNAL_ENTITY_HANDLING</code> error.</p>
        !          1461: 
        !          1462: <p>Second, instead of having the user data as its first argument, it
        !          1463: receives the parser that encountered the entity reference. This, along
        !          1464: with the context parameter, may be used as arguments to a call to
        !          1465: <code><a href= "#XML_ExternalEntityParserCreate"
        !          1466: >XML_ExternalEntityParserCreate</a></code>.  Using the returned
        !          1467: parser, the body of the external entity can be recursively parsed.</p>
        !          1468: 
        !          1469: <p>Since this handler may be called recursively, it should not be saving
        !          1470: information into global or static variables.</p>
        !          1471: </div>
        !          1472: 
        !          1473: <pre class="fcndec" id="XML_SetExternalEntityRefHandlerArg">
        !          1474: void XMLCALL
        !          1475: XML_SetExternalEntityRefHandlerArg(XML_Parser p,
        !          1476:                                    void *arg)
        !          1477: </pre>
        !          1478: <div class="fcndef">
        !          1479: <p>Set the argument passed to the ExternalEntityRefHandler.  If
        !          1480: <code>arg</code> is not NULL, it is the new value passed to the
        !          1481: handler set using <code><a href="#XML_SetExternalEntityRefHandler"
        !          1482: >XML_SetExternalEntityRefHandler</a></code>; if <code>arg</code> is
        !          1483: NULL, the argument passed to the handler function will be the parser
        !          1484: object itself.</p>
        !          1485: 
        !          1486: <p><strong>Note:</strong>
        !          1487: The type of <code>arg</code> and the type of the first argument to the
        !          1488: ExternalEntityRefHandler do not match.  This function takes a
        !          1489: <code>void *</code> to be passed to the handler, while the handler
        !          1490: accepts an <code>XML_Parser</code>.  This is a historical accident,
        !          1491: but will not be corrected before Expat 2.0 (at the earliest) to avoid
        !          1492: causing compiler warnings for code that's known to work with this
        !          1493: API.  It is the responsibility of the application code to know the
        !          1494: actual type of the argument passed to the handler and to manage it
        !          1495: properly.</p>
        !          1496: </div>
        !          1497: 
        !          1498: <div class="handler">
        !          1499: <pre class="setter" id="XML_SetSkippedEntityHandler">
        !          1500: void XMLCALL
        !          1501: XML_SetSkippedEntityHandler(XML_Parser p,
        !          1502:                             XML_SkippedEntityHandler handler)
        !          1503: </pre>
        !          1504: <pre class="signature">
        !          1505: typedef void
        !          1506: (XMLCALL *XML_SkippedEntityHandler)(void *userData,
        !          1507:                                     const XML_Char *entityName,
        !          1508:                                     int is_parameter_entity);
        !          1509: </pre>
        !          1510: <p>Set a skipped entity handler. This is called in two situations:</p>
        !          1511: <ol>
        !          1512:    <li>An entity reference is encountered for which no declaration
        !          1513:        has been read <em>and</em> this is not an error.</li>
        !          1514:    <li>An internal entity reference is read, but not expanded, because
        !          1515:        <a href="#XML_SetDefaultHandler"><code>XML_SetDefaultHandler</code></a>
        !          1516:           has been called.</li>
        !          1517: </ol>
        !          1518: <p>The <code>is_parameter_entity</code> argument will be non-zero for
        !          1519: a parameter entity and zero for a general entity.</p> <p>Note: skipped
        !          1520: parameter entities in declarations and skipped general entities in
        !          1521: attribute values cannot be reported, because the event would be out of
        !          1522: sync with the reporting of the declarations or attribute values</p>
        !          1523: </div>
        !          1524: 
        !          1525: <div class="handler">
        !          1526: <pre class="setter" id="XML_SetUnknownEncodingHandler">
        !          1527: void XMLCALL
        !          1528: XML_SetUnknownEncodingHandler(XML_Parser p,
        !          1529:                               XML_UnknownEncodingHandler enchandler,
        !          1530:                              void *encodingHandlerData)
        !          1531: </pre>
        !          1532: <pre class="signature">
        !          1533: typedef int
        !          1534: (XMLCALL *XML_UnknownEncodingHandler)(void *encodingHandlerData,
        !          1535:                                       const XML_Char *name,
        !          1536:                                       XML_Encoding *info);
        !          1537: 
        !          1538: typedef struct {
        !          1539:   int map[256];
        !          1540:   void *data;
        !          1541:   int (XMLCALL *convert)(void *data, const char *s);
        !          1542:   void (XMLCALL *release)(void *data);
        !          1543: } XML_Encoding;
        !          1544: </pre>
        !          1545: <p>Set a handler to deal with encodings other than the <a
        !          1546: href="#builtin_encodings">built in set</a>. This should be done before
        !          1547: <code><a href= "#XML_Parse" >XML_Parse</a></code> or <code><a href=
        !          1548: "#XML_ParseBuffer" >XML_ParseBuffer</a></code> have been called on the
        !          1549: given parser.</p> <p>If the handler knows how to deal with an encoding
        !          1550: with the given name, it should fill in the <code>info</code> data
        !          1551: structure and return <code>XML_STATUS_OK</code>. Otherwise it
        !          1552: should return <code>XML_STATUS_ERROR</code>. The handler will be called
        !          1553: at most once per parsed (external) entity. The optional application
        !          1554: data pointer <code>encodingHandlerData</code> will be passed back to
        !          1555: the handler.</p>
        !          1556: 
        !          1557: <p>The map array contains information for every possible possible leading
        !          1558: byte in a byte sequence. If the corresponding value is &gt;= 0, then it's
        !          1559: a single byte sequence and the byte encodes that Unicode value. If the
        !          1560: value is -1, then that byte is invalid as the initial byte in a sequence.
        !          1561: If the value is -n, where n is an integer &gt; 1, then n is the number of
        !          1562: bytes in the sequence and the actual conversion is accomplished by a
        !          1563: call to the function pointed at by convert. This function may return -1
        !          1564: if the sequence itself is invalid. The convert pointer may be null if
        !          1565: there are only single byte codes. The data parameter passed to the convert
        !          1566: function is the data pointer from <code>XML_Encoding</code>. The
        !          1567: string s is <em>NOT</em> nul-terminated and points at the sequence of
        !          1568: bytes to be converted.</p>
        !          1569: 
        !          1570: <p>The function pointed at by <code>release</code> is called by the
        !          1571: parser when it is finished with the encoding. It may be NULL.</p>
        !          1572: </div>
        !          1573: 
        !          1574: <div class="handler">
        !          1575: <pre class="setter" id="XML_SetStartNamespaceDeclHandler">
        !          1576: void XMLCALL
        !          1577: XML_SetStartNamespaceDeclHandler(XML_Parser p,
        !          1578:                                 XML_StartNamespaceDeclHandler start);
        !          1579: </pre>
        !          1580: <pre class="signature">
        !          1581: typedef void
        !          1582: (XMLCALL *XML_StartNamespaceDeclHandler)(void *userData,
        !          1583:                                          const XML_Char *prefix,
        !          1584:                                          const XML_Char *uri);
        !          1585: </pre>
        !          1586: <p>Set a handler to be called when a namespace is declared. Namespace
        !          1587: declarations occur inside start tags. But the namespace declaration start
        !          1588: handler is called before the start tag handler for each namespace declared
        !          1589: in that start tag.</p>
        !          1590: </div>
        !          1591: 
        !          1592: <div class="handler">
        !          1593: <pre class="setter" id="XML_SetEndNamespaceDeclHandler">
        !          1594: void XMLCALL
        !          1595: XML_SetEndNamespaceDeclHandler(XML_Parser p,
        !          1596:                               XML_EndNamespaceDeclHandler end);
        !          1597: </pre>
        !          1598: <pre class="signature">
        !          1599: typedef void
        !          1600: (XMLCALL *XML_EndNamespaceDeclHandler)(void *userData,
        !          1601:                                        const XML_Char *prefix);
        !          1602: </pre>
        !          1603: <p>Set a handler to be called when leaving the scope of a namespace
        !          1604: declaration. This will be called, for each namespace declaration,
        !          1605: after the handler for the end tag of the element in which the
        !          1606: namespace was declared.</p>
        !          1607: </div>
        !          1608: 
        !          1609: <div class="handler">
        !          1610: <pre class="setter" id="XML_SetNamespaceDeclHandler">
        !          1611: void XMLCALL
        !          1612: XML_SetNamespaceDeclHandler(XML_Parser p,
        !          1613:                             XML_StartNamespaceDeclHandler start,
        !          1614:                             XML_EndNamespaceDeclHandler end)
        !          1615: </pre>
        !          1616: <p>Sets both namespace declaration handlers with a single call.</p>
        !          1617: </div>
        !          1618: 
        !          1619: <div class="handler">
        !          1620: <pre class="setter" id="XML_SetXmlDeclHandler">
        !          1621: void XMLCALL
        !          1622: XML_SetXmlDeclHandler(XML_Parser p,
        !          1623:                      XML_XmlDeclHandler xmldecl);
        !          1624: </pre>
        !          1625: <pre class="signature">
        !          1626: typedef void
        !          1627: (XMLCALL *XML_XmlDeclHandler)(void            *userData,
        !          1628:                               const XML_Char  *version,
        !          1629:                               const XML_Char  *encoding,
        !          1630:                               int             standalone);
        !          1631: </pre>
        !          1632: <p>Sets a handler that is called for XML declarations and also for
        !          1633: text declarations discovered in external entities. The way to
        !          1634: distinguish is that the <code>version</code> parameter will be NULL
        !          1635: for text declarations. The <code>encoding</code> parameter may be NULL
        !          1636: for an XML declaration. The <code>standalone</code> argument will
        !          1637: contain -1, 0, or 1 indicating respectively that there was no
        !          1638: standalone parameter in the declaration, that it was given as no, or
        !          1639: that it was given as yes.</p>
        !          1640: </div>
        !          1641: 
        !          1642: <div class="handler">
        !          1643: <pre class="setter" id="XML_SetStartDoctypeDeclHandler">
        !          1644: void XMLCALL
        !          1645: XML_SetStartDoctypeDeclHandler(XML_Parser p,
        !          1646:                               XML_StartDoctypeDeclHandler start);
        !          1647: </pre>
        !          1648: <pre class="signature">
        !          1649: typedef void
        !          1650: (XMLCALL *XML_StartDoctypeDeclHandler)(void           *userData,
        !          1651:                                        const XML_Char *doctypeName,
        !          1652:                                        const XML_Char *sysid,
        !          1653:                                        const XML_Char *pubid,
        !          1654:                                        int            has_internal_subset);
        !          1655: </pre>
        !          1656: <p>Set a handler that is called at the start of a DOCTYPE declaration,
        !          1657: before any external or internal subset is parsed. Both <code>sysid</code>
        !          1658: and <code>pubid</code> may be NULL. The <code>has_internal_subset</code>
        !          1659: will be non-zero if the DOCTYPE declaration has an internal subset.</p>
        !          1660: </div>
        !          1661: 
        !          1662: <div class="handler">
        !          1663: <pre class="setter" id="XML_SetEndDoctypeDeclHandler">
        !          1664: void XMLCALL
        !          1665: XML_SetEndDoctypeDeclHandler(XML_Parser p,
        !          1666:                             XML_EndDoctypeDeclHandler end);
        !          1667: </pre>
        !          1668: <pre class="signature">
        !          1669: typedef void
        !          1670: (XMLCALL *XML_EndDoctypeDeclHandler)(void *userData);
        !          1671: </pre>
        !          1672: <p>Set a handler that is called at the end of a DOCTYPE declaration,
        !          1673: after parsing any external subset.</p>
        !          1674: </div>
        !          1675: 
        !          1676: <div class="handler">
        !          1677: <pre class="setter" id="XML_SetDoctypeDeclHandler">
        !          1678: void XMLCALL
        !          1679: XML_SetDoctypeDeclHandler(XML_Parser p,
        !          1680:                          XML_StartDoctypeDeclHandler start,
        !          1681:                          XML_EndDoctypeDeclHandler end);
        !          1682: </pre>
        !          1683: <p>Set both doctype handlers with one call.</p>
        !          1684: </div>
        !          1685: 
        !          1686: <div class="handler">
        !          1687: <pre class="setter" id="XML_SetElementDeclHandler">
        !          1688: void XMLCALL
        !          1689: XML_SetElementDeclHandler(XML_Parser p,
        !          1690:                          XML_ElementDeclHandler eldecl);
        !          1691: </pre>
        !          1692: <pre class="signature">
        !          1693: typedef void
        !          1694: (XMLCALL *XML_ElementDeclHandler)(void *userData,
        !          1695:                                   const XML_Char *name,
        !          1696:                                   XML_Content *model);
        !          1697: </pre>
        !          1698: <pre class="signature">
        !          1699: enum XML_Content_Type {
        !          1700:   XML_CTYPE_EMPTY = 1,
        !          1701:   XML_CTYPE_ANY,
        !          1702:   XML_CTYPE_MIXED,
        !          1703:   XML_CTYPE_NAME,
        !          1704:   XML_CTYPE_CHOICE,
        !          1705:   XML_CTYPE_SEQ
        !          1706: };
        !          1707: 
        !          1708: enum XML_Content_Quant {
        !          1709:   XML_CQUANT_NONE,
        !          1710:   XML_CQUANT_OPT,
        !          1711:   XML_CQUANT_REP,
        !          1712:   XML_CQUANT_PLUS
        !          1713: };
        !          1714: 
        !          1715: typedef struct XML_cp XML_Content;
        !          1716: 
        !          1717: struct XML_cp {
        !          1718:   enum XML_Content_Type                type;
        !          1719:   enum XML_Content_Quant       quant;
        !          1720:   const XML_Char *             name;
        !          1721:   unsigned int                 numchildren;
        !          1722:   XML_Content *                        children;
        !          1723: };
        !          1724: </pre>
        !          1725: <p>Sets a handler for element declarations in a DTD. The handler gets
        !          1726: called with the name of the element in the declaration and a pointer
        !          1727: to a structure that contains the element model. It is the
        !          1728: application's responsibility to free this data structure using
        !          1729: <code><a href="#XML_FreeContentModel"
        !          1730: >XML_FreeContentModel</a></code>.</p>
        !          1731: 
        !          1732: <p>The <code>model</code> argument is the root of a tree of
        !          1733: <code>XML_Content</code> nodes. If <code>type</code> equals
        !          1734: <code>XML_CTYPE_EMPTY</code> or <code>XML_CTYPE_ANY</code>, then
        !          1735: <code>quant</code> will be <code>XML_CQUANT_NONE</code>, and the other
        !          1736: fields will be zero or NULL.  If <code>type</code> is
        !          1737: <code>XML_CTYPE_MIXED</code>, then <code>quant</code> will be
        !          1738: <code>XML_CQUANT_NONE</code> or <code>XML_CQUANT_REP</code> and
        !          1739: <code>numchildren</code> will contain the number of elements that are
        !          1740: allowed to be mixed in and <code>children</code> points to an array of
        !          1741: <code>XML_Content</code> structures that will all have type
        !          1742: XML_CTYPE_NAME with no quantification.  Only the root node can be type
        !          1743: <code>XML_CTYPE_EMPTY</code>, <code>XML_CTYPE_ANY</code>, or
        !          1744: <code>XML_CTYPE_MIXED</code>.</p>
        !          1745: 
        !          1746: <p>For type <code>XML_CTYPE_NAME</code>, the <code>name</code> field
        !          1747: points to the name and the <code>numchildren</code> and
        !          1748: <code>children</code> fields will be zero and NULL. The
        !          1749: <code>quant</code> field will indicate any quantifiers placed on the
        !          1750: name.</p>
        !          1751: 
        !          1752: <p>Types <code>XML_CTYPE_CHOICE</code> and <code>XML_CTYPE_SEQ</code>
        !          1753: indicate a choice or sequence respectively. The
        !          1754: <code>numchildren</code> field indicates how many nodes in the choice
        !          1755: or sequence and <code>children</code> points to the nodes.</p>
        !          1756: </div>
        !          1757: 
        !          1758: <div class="handler">
        !          1759: <pre class="setter" id="XML_SetAttlistDeclHandler">
        !          1760: void XMLCALL
        !          1761: XML_SetAttlistDeclHandler(XML_Parser p,
        !          1762:                           XML_AttlistDeclHandler attdecl);
        !          1763: </pre>
        !          1764: <pre class="signature">
        !          1765: typedef void
        !          1766: (XMLCALL *XML_AttlistDeclHandler)(void           *userData,
        !          1767:                                   const XML_Char *elname,
        !          1768:                                   const XML_Char *attname,
        !          1769:                                   const XML_Char *att_type,
        !          1770:                                   const XML_Char *dflt,
        !          1771:                                   int            isrequired);
        !          1772: </pre>
        !          1773: <p>Set a handler for attlist declarations in the DTD. This handler is
        !          1774: called for <em>each</em> attribute. So a single attlist declaration
        !          1775: with multiple attributes declared will generate multiple calls to this
        !          1776: handler. The <code>elname</code> parameter returns the name of the
        !          1777: element for which the attribute is being declared. The attribute name
        !          1778: is in the <code>attname</code> parameter. The attribute type is in the
        !          1779: <code>att_type</code> parameter.  It is the string representing the
        !          1780: type in the declaration with whitespace removed.</p>
        !          1781: 
        !          1782: <p>The <code>dflt</code> parameter holds the default value. It will be
        !          1783: NULL in the case of "#IMPLIED" or "#REQUIRED" attributes. You can
        !          1784: distinguish these two cases by checking the <code>isrequired</code>
        !          1785: parameter, which will be true in the case of "#REQUIRED" attributes.
        !          1786: Attributes which are "#FIXED" will have also have a true
        !          1787: <code>isrequired</code>, but they will have the non-NULL fixed value
        !          1788: in the <code>dflt</code> parameter.</p>
        !          1789: </div>
        !          1790: 
        !          1791: <div class="handler">
        !          1792: <pre class="setter" id="XML_SetEntityDeclHandler">
        !          1793: void XMLCALL
        !          1794: XML_SetEntityDeclHandler(XML_Parser p,
        !          1795:                         XML_EntityDeclHandler handler);
        !          1796: </pre>
        !          1797: <pre class="signature">
        !          1798: typedef void
        !          1799: (XMLCALL *XML_EntityDeclHandler)(void           *userData,
        !          1800:                                  const XML_Char *entityName,
        !          1801:                                  int            is_parameter_entity,
        !          1802:                                  const XML_Char *value,
        !          1803:                                  int            value_length, 
        !          1804:                                  const XML_Char *base,
        !          1805:                                  const XML_Char *systemId,
        !          1806:                                  const XML_Char *publicId,
        !          1807:                                  const XML_Char *notationName);
        !          1808: </pre>
        !          1809: <p>Sets a handler that will be called for all entity declarations.
        !          1810: The <code>is_parameter_entity</code> argument will be non-zero in the
        !          1811: case of parameter entities and zero otherwise.</p>
        !          1812: 
        !          1813: <p>For internal entities (<code>&lt;!ENTITY foo "bar"&gt;</code>),
        !          1814: <code>value</code> will be non-NULL and <code>systemId</code>,
        !          1815: <code>publicId</code>, and <code>notationName</code> will all be NULL.
        !          1816: The value string is <em>not</em> NULL terminated; the length is
        !          1817: provided in the <code>value_length</code> parameter. Do not use
        !          1818: <code>value_length</code> to test for internal entities, since it is
        !          1819: legal to have zero-length values. Instead check for whether or not
        !          1820: <code>value</code> is NULL.</p> <p>The <code>notationName</code>
        !          1821: argument will have a non-NULL value only for unparsed entity
        !          1822: declarations.</p>
        !          1823: </div>
        !          1824: 
        !          1825: <div class="handler">
        !          1826: <pre class="setter" id="XML_SetUnparsedEntityDeclHandler">
        !          1827: void XMLCALL
        !          1828: XML_SetUnparsedEntityDeclHandler(XML_Parser p,
        !          1829:                                  XML_UnparsedEntityDeclHandler h)
        !          1830: </pre>
        !          1831: <pre class="signature">
        !          1832: typedef void
        !          1833: (XMLCALL *XML_UnparsedEntityDeclHandler)(void *userData,
        !          1834:                                          const XML_Char *entityName, 
        !          1835:                                          const XML_Char *base,
        !          1836:                                          const XML_Char *systemId,
        !          1837:                                          const XML_Char *publicId,
        !          1838:                                          const XML_Char *notationName);
        !          1839: </pre>
        !          1840: <p>Set a handler that receives declarations of unparsed entities. These
        !          1841: are entity declarations that have a notation (NDATA) field:</p>
        !          1842: 
        !          1843: <div id="eg"><pre>
        !          1844: &lt;!ENTITY logo SYSTEM "images/logo.gif" NDATA gif&gt;
        !          1845: </pre></div>
        !          1846: <p>This handler is obsolete and is provided for backwards
        !          1847: compatibility.  Use instead <a href= "#XML_SetEntityDeclHandler"
        !          1848: >XML_SetEntityDeclHandler</a>.</p>
        !          1849: </div>
        !          1850: 
        !          1851: <div class="handler">
        !          1852: <pre class="setter" id="XML_SetNotationDeclHandler">
        !          1853: void XMLCALL
        !          1854: XML_SetNotationDeclHandler(XML_Parser p,
        !          1855:                            XML_NotationDeclHandler h)
        !          1856: </pre>
        !          1857: <pre class="signature">
        !          1858: typedef void
        !          1859: (XMLCALL *XML_NotationDeclHandler)(void *userData, 
        !          1860:                                    const XML_Char *notationName,
        !          1861:                                    const XML_Char *base,
        !          1862:                                    const XML_Char *systemId,
        !          1863:                                    const XML_Char *publicId);
        !          1864: </pre>
        !          1865: <p>Set a handler that receives notation declarations.</p>
        !          1866: </div>
        !          1867: 
        !          1868: <div class="handler">
        !          1869: <pre class="setter" id="XML_SetNotStandaloneHandler">
        !          1870: void XMLCALL
        !          1871: XML_SetNotStandaloneHandler(XML_Parser p,
        !          1872:                             XML_NotStandaloneHandler h)
        !          1873: </pre>
        !          1874: <pre class="signature">
        !          1875: typedef int 
        !          1876: (XMLCALL *XML_NotStandaloneHandler)(void *userData);
        !          1877: </pre>
        !          1878: <p>Set a handler that is called if the document is not "standalone".
        !          1879: This happens when there is an external subset or a reference to a
        !          1880: parameter entity, but does not have standalone set to "yes" in an XML
        !          1881: declaration.  If this handler returns <code>XML_STATUS_ERROR</code>,
        !          1882: then the parser will throw an <code>XML_ERROR_NOT_STANDALONE</code>
        !          1883: error.</p>
        !          1884: </div>
        !          1885: 
        !          1886: <h3><a name="position">Parse position and error reporting functions</a></h3>
        !          1887: 
        !          1888: <p>These are the functions you'll want to call when the parse
        !          1889: functions return <code>XML_STATUS_ERROR</code> (a parse error has
        !          1890: occurred), although the position reporting functions are useful outside
        !          1891: of errors. The position reported is the byte position (in the original
        !          1892: document or entity encoding) of the first of the sequence of
        !          1893: characters that generated the current event (or the error that caused
        !          1894: the parse functions to return <code>XML_STATUS_ERROR</code>.)  The
        !          1895: exceptions are callbacks trigged by declarations in the document
        !          1896: prologue, in which case they exact position reported is somewhere in the
        !          1897: relevant markup, but not necessarily as meaningful as for other
        !          1898: events.</p>
        !          1899: 
        !          1900: <p>The position reporting functions are accurate only outside of the
        !          1901: DTD.  In other words, they usually return bogus information when
        !          1902: called from within a DTD declaration handler.</p>
        !          1903: 
        !          1904: <pre class="fcndec" id="XML_GetErrorCode">
        !          1905: enum XML_Error XMLCALL
        !          1906: XML_GetErrorCode(XML_Parser p);
        !          1907: </pre>
        !          1908: <div class="fcndef">
        !          1909: Return what type of error has occurred.
        !          1910: </div>
        !          1911: 
        !          1912: <pre class="fcndec" id="XML_ErrorString">
        !          1913: const XML_LChar * XMLCALL
        !          1914: XML_ErrorString(enum XML_Error code);
        !          1915: </pre>
        !          1916: <div class="fcndef">
        !          1917: Return a string describing the error corresponding to code.
        !          1918: The code should be one of the enums that can be returned from
        !          1919: <code><a href= "#XML_GetErrorCode" >XML_GetErrorCode</a></code>.
        !          1920: </div>
        !          1921: 
        !          1922: <pre class="fcndec" id="XML_GetCurrentByteIndex">
        !          1923: XML_Index XMLCALL
        !          1924: XML_GetCurrentByteIndex(XML_Parser p);
        !          1925: </pre>
        !          1926: <div class="fcndef">
        !          1927: Return the byte offset of the position.  This always corresponds to
        !          1928: the values returned by <code><a href= "#XML_GetCurrentLineNumber"
        !          1929: >XML_GetCurrentLineNumber</a></code> and <code><a href=
        !          1930: "#XML_GetCurrentColumnNumber" >XML_GetCurrentColumnNumber</a></code>.
        !          1931: </div>
        !          1932: 
        !          1933: <pre class="fcndec" id="XML_GetCurrentLineNumber">
        !          1934: XML_Size XMLCALL
        !          1935: XML_GetCurrentLineNumber(XML_Parser p);
        !          1936: </pre>
        !          1937: <div class="fcndef">
        !          1938: Return the line number of the position.  The first line is reported as
        !          1939: <code>1</code>.
        !          1940: </div>
        !          1941: 
        !          1942: <pre class="fcndec" id="XML_GetCurrentColumnNumber">
        !          1943: XML_Size XMLCALL
        !          1944: XML_GetCurrentColumnNumber(XML_Parser p);
        !          1945: </pre>
        !          1946: <div class="fcndef">
        !          1947: Return the offset, from the beginning of the current line, of
        !          1948: the position.
        !          1949: </div>
        !          1950: 
        !          1951: <pre class="fcndec" id="XML_GetCurrentByteCount">
        !          1952: int XMLCALL
        !          1953: XML_GetCurrentByteCount(XML_Parser p);
        !          1954: </pre>
        !          1955: <div class="fcndef">
        !          1956: Return the number of bytes in the current event. Returns
        !          1957: <code>0</code> if the event is inside a reference to an internal
        !          1958: entity and for the end-tag event for empty element tags (the later can
        !          1959: be used to distinguish empty-element tags from empty elements using
        !          1960: separate start and end tags).
        !          1961: </div>
        !          1962: 
        !          1963: <pre class="fcndec" id="XML_GetInputContext">
        !          1964: const char * XMLCALL
        !          1965: XML_GetInputContext(XML_Parser p,
        !          1966:                     int *offset,
        !          1967:                     int *size);
        !          1968: </pre>
        !          1969: <div class="fcndef">
        !          1970: 
        !          1971: <p>Returns the parser's input buffer, sets the integer pointed at by
        !          1972: <code>offset</code> to the offset within this buffer of the current
        !          1973: parse position, and set the integer pointed at by <code>size</code> to
        !          1974: the size of the returned buffer.</p>
        !          1975: 
        !          1976: <p>This should only be called from within a handler during an active
        !          1977: parse and the returned buffer should only be referred to from within
        !          1978: the handler that made the call. This input buffer contains the
        !          1979: untranslated bytes of the input.</p>
        !          1980: 
        !          1981: <p>Only a limited amount of context is kept, so if the event
        !          1982: triggering a call spans over a very large amount of input, the actual
        !          1983: parse position may be before the beginning of the buffer.</p>
        !          1984: 
        !          1985: <p>If <code>XML_CONTEXT_BYTES</code> is not defined, this will always
        !          1986: return NULL.</p>
        !          1987: </div>
        !          1988: 
        !          1989: <h3><a name="miscellaneous">Miscellaneous functions</a></h3>
        !          1990: 
        !          1991: <p>The functions in this section either obtain state information from
        !          1992: the parser or can be used to dynamicly set parser options.</p>
        !          1993: 
        !          1994: <pre class="fcndec" id="XML_SetUserData">
        !          1995: void XMLCALL
        !          1996: XML_SetUserData(XML_Parser p,
        !          1997:                 void *userData);
        !          1998: </pre>
        !          1999: <div class="fcndef">
        !          2000: This sets the user data pointer that gets passed to handlers.  It
        !          2001: overwrites any previous value for this pointer. Note that the
        !          2002: application is responsible for freeing the memory associated with
        !          2003: <code>userData</code> when it is finished with the parser. So if you
        !          2004: call this when there's already a pointer there, and you haven't freed
        !          2005: the memory associated with it, then you've probably just leaked
        !          2006: memory.
        !          2007: </div>
        !          2008: 
        !          2009: <pre class="fcndec" id="XML_GetUserData">
        !          2010: void * XMLCALL
        !          2011: XML_GetUserData(XML_Parser p);
        !          2012: </pre>
        !          2013: <div class="fcndef">
        !          2014: This returns the user data pointer that gets passed to handlers.
        !          2015: It is actually implemented as a macro.
        !          2016: </div>
        !          2017: 
        !          2018: <pre class="fcndec" id="XML_UseParserAsHandlerArg">
        !          2019: void XMLCALL
        !          2020: XML_UseParserAsHandlerArg(XML_Parser p);
        !          2021: </pre>
        !          2022: <div class="fcndef">
        !          2023: After this is called, handlers receive the parser in their
        !          2024: <code>userData</code> arguments.  The user data can still be obtained
        !          2025: using the <code><a href= "#XML_GetUserData"
        !          2026: >XML_GetUserData</a></code> function.
        !          2027: </div>
        !          2028: 
        !          2029: <pre class="fcndec" id="XML_SetBase">
        !          2030: enum XML_Status XMLCALL
        !          2031: XML_SetBase(XML_Parser p,
        !          2032:             const XML_Char *base);
        !          2033: </pre>
        !          2034: <div class="fcndef">
        !          2035: Set the base to be used for resolving relative URIs in system
        !          2036: identifiers.  The return value is <code>XML_STATUS_ERROR</code> if
        !          2037: there's no memory to store base, otherwise it's
        !          2038: <code>XML_STATUS_OK</code>.
        !          2039: </div>
        !          2040: 
        !          2041: <pre class="fcndec" id="XML_GetBase">
        !          2042: const XML_Char * XMLCALL
        !          2043: XML_GetBase(XML_Parser p);
        !          2044: </pre>
        !          2045: <div class="fcndef">
        !          2046: Return the base for resolving relative URIs.
        !          2047: </div>
        !          2048: 
        !          2049: <pre class="fcndec" id="XML_GetSpecifiedAttributeCount">
        !          2050: int XMLCALL
        !          2051: XML_GetSpecifiedAttributeCount(XML_Parser p);
        !          2052: </pre>
        !          2053: <div class="fcndef">
        !          2054: When attributes are reported to the start handler in the atts vector,
        !          2055: attributes that were explicitly set in the element occur before any
        !          2056: attributes that receive their value from default information in an
        !          2057: ATTLIST declaration. This function returns the number of attributes
        !          2058: that were explicitly set times two, thus giving the offset in the
        !          2059: <code>atts</code> array passed to the start tag handler of the first
        !          2060: attribute set due to defaults. It supplies information for the last
        !          2061: call to a start handler. If called inside a start handler, then that
        !          2062: means the current call.
        !          2063: </div>
        !          2064: 
        !          2065: <pre class="fcndec" id="XML_GetIdAttributeIndex">
        !          2066: int XMLCALL
        !          2067: XML_GetIdAttributeIndex(XML_Parser p);
        !          2068: </pre>
        !          2069: <div class="fcndef">
        !          2070: Returns the index of the ID attribute passed in the atts array in the
        !          2071: last call to <code><a href= "#XML_StartElementHandler"
        !          2072: >XML_StartElementHandler</a></code>, or -1 if there is no ID
        !          2073: attribute. If called inside a start handler, then that means the
        !          2074: current call.
        !          2075: </div>
        !          2076: 
        !          2077: <pre class="fcndec" id="XML_SetEncoding">
        !          2078: enum XML_Status XMLCALL
        !          2079: XML_SetEncoding(XML_Parser p,
        !          2080:                 const XML_Char *encoding);
        !          2081: </pre>
        !          2082: <div class="fcndef">
        !          2083: Set the encoding to be used by the parser. It is equivalent to
        !          2084: passing a non-null encoding argument to the parser creation functions.
        !          2085: It must not be called after <code><a href= "#XML_Parse"
        !          2086: >XML_Parse</a></code> or <code><a href= "#XML_ParseBuffer"
        !          2087: >XML_ParseBuffer</a></code> have been called on the given parser.
        !          2088: Returns <code>XML_STATUS_OK</code> on success or
        !          2089: <code>XML_STATUS_ERROR</code> on error.
        !          2090: </div>
        !          2091: 
        !          2092: <pre class="fcndec" id="XML_SetParamEntityParsing">
        !          2093: int XMLCALL
        !          2094: XML_SetParamEntityParsing(XML_Parser p,
        !          2095:                           enum XML_ParamEntityParsing code);
        !          2096: </pre>
        !          2097: <div class="fcndef">
        !          2098: This enables parsing of parameter entities, including the external
        !          2099: parameter entity that is the external DTD subset, according to
        !          2100: <code>code</code>.
        !          2101: The choices for <code>code</code> are:
        !          2102: <ul>
        !          2103: <li><code>XML_PARAM_ENTITY_PARSING_NEVER</code></li>
        !          2104: <li><code>XML_PARAM_ENTITY_PARSING_UNLESS_STANDALONE</code></li>
        !          2105: <li><code>XML_PARAM_ENTITY_PARSING_ALWAYS</code></li>
        !          2106: </ul>
        !          2107: </div>
        !          2108: 
        !          2109: <pre class="fcndec" id="XML_UseForeignDTD">
        !          2110: enum XML_Error XMLCALL
        !          2111: XML_UseForeignDTD(XML_Parser parser, XML_Bool useDTD);
        !          2112: </pre>
        !          2113: <div class="fcndef">
        !          2114: <p>This function allows an application to provide an external subset
        !          2115: for the document type declaration for documents which do not specify
        !          2116: an external subset of their own.  For documents which specify an
        !          2117: external subset in their DOCTYPE declaration, the application-provided
        !          2118: subset will be ignored.  If the document does not contain a DOCTYPE
        !          2119: declaration at all and <code>useDTD</code> is true, the
        !          2120: application-provided subset will be parsed, but the
        !          2121: <code>startDoctypeDeclHandler</code> and
        !          2122: <code>endDoctypeDeclHandler</code> functions, if set, will not be
        !          2123: called.  The setting of parameter entity parsing, controlled using
        !          2124: <code><a href= "#XML_SetParamEntityParsing"
        !          2125: >XML_SetParamEntityParsing</a></code>, will be honored.</p>
        !          2126: 
        !          2127: <p>The application-provided external subset is read by calling the
        !          2128: external entity reference handler set via <code><a href=
        !          2129: "#XML_SetExternalEntityRefHandler"
        !          2130: >XML_SetExternalEntityRefHandler</a></code> with both
        !          2131: <code>publicId</code> and <code>systemId</code> set to NULL.</p>
        !          2132: 
        !          2133: <p>If this function is called after parsing has begun, it returns
        !          2134: <code>XML_ERROR_CANT_CHANGE_FEATURE_ONCE_PARSING</code> and ignores
        !          2135: <code>useDTD</code>.  If called when Expat has been compiled without
        !          2136: DTD support, it returns
        !          2137: <code>XML_ERROR_FEATURE_REQUIRES_XML_DTD</code>.  Otherwise, it
        !          2138: returns <code>XML_ERROR_NONE</code>.</p>
        !          2139: 
        !          2140: <p><b>Note:</b> For the purpose of checking WFC: Entity Declared, passing
        !          2141: <code>useDTD == XML_TRUE</code> will make the parser behave as if
        !          2142: the document had a DTD with an external subset. This holds true even if
        !          2143: the external entity reference handler returns without action.</p>
        !          2144: </div>
        !          2145: 
        !          2146: <pre class="fcndec" id="XML_SetReturnNSTriplet">
        !          2147: void XMLCALL
        !          2148: XML_SetReturnNSTriplet(XML_Parser parser,
        !          2149:                        int        do_nst);
        !          2150: </pre>
        !          2151: <div class="fcndef">
        !          2152: <p>
        !          2153: This function only has an effect when using a parser created with
        !          2154: <code><a href= "#XML_ParserCreateNS" >XML_ParserCreateNS</a></code>,
        !          2155: i.e. when namespace processing is in effect. The <code>do_nst</code>
        !          2156: sets whether or not prefixes are returned with names qualified with a
        !          2157: namespace prefix. If this function is called with <code>do_nst</code>
        !          2158: non-zero, then afterwards namespace qualified names (that is qualified
        !          2159: with a prefix as opposed to belonging to a default namespace) are
        !          2160: returned as a triplet with the three parts separated by the namespace
        !          2161: separator specified when the parser was created.  The order of
        !          2162: returned parts is URI, local name, and prefix.</p> <p>If
        !          2163: <code>do_nst</code> is zero, then namespaces are reported in the
        !          2164: default manner, URI then local_name separated by the namespace
        !          2165: separator.</p>
        !          2166: </div>
        !          2167: 
        !          2168: <pre class="fcndec" id="XML_DefaultCurrent">
        !          2169: void XMLCALL
        !          2170: XML_DefaultCurrent(XML_Parser parser);
        !          2171: </pre>
        !          2172: <div class="fcndef">
        !          2173: This can be called within a handler for a start element, end element,
        !          2174: processing instruction or character data.  It causes the corresponding
        !          2175: markup to be passed to the default handler set by <code><a
        !          2176: href="#XML_SetDefaultHandler" >XML_SetDefaultHandler</a></code> or
        !          2177: <code><a href="#XML_SetDefaultHandlerExpand"
        !          2178: >XML_SetDefaultHandlerExpand</a></code>.  It does nothing if there is
        !          2179: not a default handler.
        !          2180: </div>
        !          2181: 
        !          2182: <pre class="fcndec" id="XML_ExpatVersion">
        !          2183: XML_LChar * XMLCALL
        !          2184: XML_ExpatVersion();
        !          2185: </pre>
        !          2186: <div class="fcndef">
        !          2187: Return the library version as a string (e.g. <code>"expat_1.95.1"</code>).
        !          2188: </div>
        !          2189: 
        !          2190: <pre class="fcndec" id="XML_ExpatVersionInfo">
        !          2191: struct XML_Expat_Version XMLCALL
        !          2192: XML_ExpatVersionInfo();
        !          2193: </pre>
        !          2194: <pre class="signature">
        !          2195: typedef struct {
        !          2196:   int major;
        !          2197:   int minor;
        !          2198:   int micro;
        !          2199: } XML_Expat_Version;
        !          2200: </pre>
        !          2201: <div class="fcndef">
        !          2202: Return the library version information as a structure.
        !          2203: Some macros are also defined that support compile-time tests of the
        !          2204: library version:
        !          2205: <ul>
        !          2206: <li><code>XML_MAJOR_VERSION</code></li>
        !          2207: <li><code>XML_MINOR_VERSION</code></li>
        !          2208: <li><code>XML_MICRO_VERSION</code></li>
        !          2209: </ul>
        !          2210: Testing these constants is currently the best way to determine if
        !          2211: particular parts of the Expat API are available.
        !          2212: </div>
        !          2213: 
        !          2214: <pre class="fcndec" id="XML_GetFeatureList">
        !          2215: const XML_Feature * XMLCALL
        !          2216: XML_GetFeatureList();
        !          2217: </pre>
        !          2218: <pre class="signature">
        !          2219: enum XML_FeatureEnum {
        !          2220:   XML_FEATURE_END = 0,
        !          2221:   XML_FEATURE_UNICODE,
        !          2222:   XML_FEATURE_UNICODE_WCHAR_T,
        !          2223:   XML_FEATURE_DTD,
        !          2224:   XML_FEATURE_CONTEXT_BYTES,
        !          2225:   XML_FEATURE_MIN_SIZE,
        !          2226:   XML_FEATURE_SIZEOF_XML_CHAR,
        !          2227:   XML_FEATURE_SIZEOF_XML_LCHAR,
        !          2228:   XML_FEATURE_NS,
        !          2229:   XML_FEATURE_LARGE_SIZE
        !          2230: };
        !          2231: 
        !          2232: typedef struct {
        !          2233:   enum XML_FeatureEnum  feature;
        !          2234:   XML_LChar            *name;
        !          2235:   long int              value;
        !          2236: } XML_Feature;
        !          2237: </pre>
        !          2238: <div class="fcndef">
        !          2239: <p>Returns a list of "feature" records, providing details on how
        !          2240: Expat was configured at compile time.  Most applications should not
        !          2241: need to worry about this, but this information is otherwise not
        !          2242: available from Expat.  This function allows code that does need to
        !          2243: check these features to do so at runtime.</p>
        !          2244: 
        !          2245: <p>The return value is an array of <code>XML_Feature</code>,
        !          2246: terminated by a record with a <code>feature</code> of
        !          2247: <code>XML_FEATURE_END</code> and <code>name</code> of NULL,
        !          2248: identifying the feature-test macros Expat was compiled with.  Since an
        !          2249: application that requires this kind of information needs to determine
        !          2250: the type of character the <code>name</code> points to, records for the
        !          2251: <code>XML_FEATURE_SIZEOF_XML_CHAR</code> and
        !          2252: <code>XML_FEATURE_SIZEOF_XML_LCHAR</code> will be located at the
        !          2253: beginning of the list, followed by <code>XML_FEATURE_UNICODE</code>
        !          2254: and <code>XML_FEATURE_UNICODE_WCHAR_T</code>, if they are present at
        !          2255: all.</p>
        !          2256: 
        !          2257: <p>Some features have an associated value.  If there isn't an
        !          2258: associated value, the <code>value</code> field is set to 0.  At this
        !          2259: time, the following features have been defined to have values:</p>
        !          2260: 
        !          2261: <dl>
        !          2262:   <dt><code>XML_FEATURE_SIZEOF_XML_CHAR</code></dt>
        !          2263:   <dd>The number of bytes occupied by one <code>XML_Char</code>
        !          2264:   character.</dd>
        !          2265:   <dt><code>XML_FEATURE_SIZEOF_XML_LCHAR</code></dt>
        !          2266:   <dd>The number of bytes occupied by one <code>XML_LChar</code>
        !          2267:   character.</dd>
        !          2268:   <dt><code>XML_FEATURE_CONTEXT_BYTES</code></dt>
        !          2269:   <dd>The maximum number of characters of context which can be
        !          2270:   reported by <code><a href= "#XML_GetInputContext"
        !          2271:   >XML_GetInputContext</a></code>.</dd>
        !          2272: </dl>
        !          2273: </div>
        !          2274: 
        !          2275: <pre class="fcndec" id="XML_FreeContentModel">
        !          2276: void XMLCALL
        !          2277: XML_FreeContentModel(XML_Parser parser, XML_Content *model);
        !          2278: </pre>
        !          2279: <div class="fcndef">
        !          2280: Function to deallocate the <code>model</code> argument passed to the
        !          2281: <code>XML_ElementDeclHandler</code> callback set using <code><a
        !          2282: href="#XML_SetElementDeclHandler" >XML_ElementDeclHandler</a></code>.
        !          2283: This function should not be used for any other purpose.
        !          2284: </div>
        !          2285: 
        !          2286: <p>The following functions allow external code to share the memory
        !          2287: allocator an <code>XML_Parser</code> has been configured to use.  This
        !          2288: is especially useful for third-party libraries that interact with a
        !          2289: parser object created by application code, or heavily layered
        !          2290: applications.  This can be essential when using dynamically loaded
        !          2291: libraries which use different C standard libraries (this can happen on
        !          2292: Windows, at least).</p>
        !          2293: 
        !          2294: <pre class="fcndec" id="XML_MemMalloc">
        !          2295: void * XMLCALL
        !          2296: XML_MemMalloc(XML_Parser parser, size_t size);
        !          2297: </pre>
        !          2298: <div class="fcndef">
        !          2299: Allocate <code>size</code> bytes of memory using the allocator the
        !          2300: <code>parser</code> object has been configured to use.  Returns a
        !          2301: pointer to the memory or NULL on failure.  Memory allocated in this
        !          2302: way must be freed using <code><a href="#XML_MemFree"
        !          2303: >XML_MemFree</a></code>.
        !          2304: </div>
        !          2305: 
        !          2306: <pre class="fcndec" id="XML_MemRealloc">
        !          2307: void * XMLCALL
        !          2308: XML_MemRealloc(XML_Parser parser, void *ptr, size_t size);
        !          2309: </pre>
        !          2310: <div class="fcndef">
        !          2311: Allocate <code>size</code> bytes of memory using the allocator the
        !          2312: <code>parser</code> object has been configured to use.
        !          2313: <code>ptr</code> must point to a block of memory allocated by <code><a
        !          2314: href="#XML_MemMalloc" >XML_MemMalloc</a></code> or
        !          2315: <code>XML_MemRealloc</code>, or be NULL.  This function tries to
        !          2316: expand the block pointed to by <code>ptr</code> if possible.  Returns
        !          2317: a pointer to the memory or NULL on failure.  On success, the original
        !          2318: block has either been expanded or freed.  On failure, the original
        !          2319: block has not been freed; the caller is responsible for freeing the
        !          2320: original block.  Memory allocated in this way must be freed using
        !          2321: <code><a href="#XML_MemFree"
        !          2322: >XML_MemFree</a></code>.
        !          2323: </div>
        !          2324: 
        !          2325: <pre class="fcndec" id="XML_MemFree">
        !          2326: void XMLCALL
        !          2327: XML_MemFree(XML_Parser parser, void *ptr);
        !          2328: </pre>
        !          2329: <div class="fcndef">
        !          2330: Free a block of memory pointed to by <code>ptr</code>.  The block must
        !          2331: have been allocated by <code><a href="#XML_MemMalloc"
        !          2332: >XML_MemMalloc</a></code> or <code>XML_MemRealloc</code>, or be NULL.
        !          2333: </div>
        !          2334: 
        !          2335: <hr />
        !          2336: <p><a href="http://validator.w3.org/check/referer"><img
        !          2337:         src="valid-xhtml10.png" alt="Valid XHTML 1.0!"
        !          2338:         height="31" width="88" class="noborder" /></a></p>
        !          2339: </div>
        !          2340: </body>
        !          2341: </html>

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