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    2. 

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  10. </style><title>FAQ</title></head><body bgcolor="#8b7765" text="#000000" link="#a06060" vlink="#000000"><table border="0" width="100%" cellpadding="5" cellspacing="0" align="center"><tr><td width="120"><a href="http://swpat.ffii.org/"><img src="epatents.png" alt="Action against software patents" /></a></td><td width="180"><a href="http://www.gnome.org/"><img src="gnome2.png" alt="Gnome2 Logo" /></a><a href="http://www.w3.org/Status"><img src="w3c.png" alt="W3C Logo" /></a><a href="http://www.redhat.com/"><img src="redhat.gif" alt="Red Hat Logo" /></a><div align="left"><a href="http://xmlsoft.org/"><img src="Libxml2-Logo-180x168.gif" alt="Made with Libxml2 Logo" /></a></div></td><td><table border="0" width="90%" cellpadding="2" cellspacing="0" align="center" bgcolor="#000000"><tr><td><table width="100%" border="0" cellspacing="1" cellpadding="3" bgcolor="#fffacd"><tr><td align="center"><h1>The XML C parser and toolkit of Gnome</h1><h2>FAQ</h2></td></tr></table></td></tr></table></td></tr></table><table border="0" cellpadding="4" cellspacing="0" width="100%" align="center"><tr><td bgcolor="#8b7765"><table border="0" cellspacing="0" cellpadding="2" width="100%"><tr><td valign="top" width="200" bgcolor="#8b7765"><table border="0" cellspacing="0" cellpadding="1" width="100%" bgcolor="#000000"><tr><td><table width="100%" border="0" cellspacing="1" cellpadding="3"><tr><td colspan="1" bgcolor="#eecfa1" align="center"><center><b>Main Menu</b></center></td></tr><tr><td bgcolor="#fffacd"><form action="search.php" enctype="application/x-www-form-urlencoded" method="get"><input name="query" type="text" size="20" value="" /><input name="submit" type="submit" value="Search ..." /></form><ul><li><a href="index.html">Home</a></li><li><a href="html/index.html">Reference Manual</a></li><li><a href="intro.html">Introduction</a></li><li><a href="FAQ.html">FAQ</a></li><li><a href="docs.html" style="font-weight:bold">Developer Menu</a></li><li><a href="bugs.html">Reporting bugs and getting help</a></li><li><a href="help.html">How to help</a></li><li><a href="downloads.html">Downloads</a></li><li><a href="news.html">Releases</a></li><li><a href="XMLinfo.html">XML</a></li><li><a href="XSLT.html">XSLT</a></li><li><a href="xmldtd.html">Validation &amp; DTDs</a></li><li><a href="encoding.html">Encodings support</a></li><li><a href="catalog.html">Catalog support</a></li><li><a href="namespaces.html">Namespaces</a></li><li><a href="contribs.html">Contributions</a></li><li><a href="examples/index.html" style="font-weight:bold">Code Examples</a></li><li><a href="html/index.html" style="font-weight:bold">API Menu</a></li><li><a href="guidelines.html">XML Guidelines</a></li><li><a href="ChangeLog.html">Recent Changes</a></li></ul></td></tr></table><table width="100%" border="0" cellspacing="1" cellpadding="3"><tr><td colspan="1" bgcolor="#eecfa1" align="center"><center><b>Related links</b></center></td></tr><tr><td bgcolor="#fffacd"><ul><li><a href="http://mail.gnome.org/archives/xml/">Mail archive</a></li><li><a href="http://xmlsoft.org/XSLT/">XSLT libxslt</a></li><li><a href="http://phd.cs.unibo.it/gdome2/">DOM gdome2</a></li><li><a href="http://www.aleksey.com/xmlsec/">XML-DSig xmlsec</a></li><li><a href="ftp://xmlsoft.org/">FTP</a></li><li><a href="http://www.zlatkovic.com/projects/libxml/">Windows binaries</a></li><li><a href="http://opencsw.org/packages/libxml2">Solaris binaries</a></li><li><a href="http://www.explain.com.au/oss/libxml2xslt.html">MacOsX binaries</a></li><li><a href="http://codespeak.net/lxml/">lxml Python bindings</a></li><li><a href="http://cpan.uwinnipeg.ca/dist/XML-LibXML">Perl bindings</a></li><li><a href="http://libxmlplusplus.sourceforge.net/">C++ bindings</a></li><li><a href="http://www.zend.com/php5/articles/php5-xmlphp.php#Heading4">PHP bindings</a></li><li><a href="http://sourceforge.net/projects/libxml2-pas/">Pascal bindings</a></li><li><a href="http://libxml.rubyforge.org/">Ruby bindings</a></li><li><a href="http://tclxml.sourceforge.net/">Tcl bindings</a></li><li><a href="http://bugzilla.gnome.org/buglist.cgi?product=libxml2">Bug Tracker</a></li></ul></td></tr></table></td></tr></table></td><td valign="top" bgcolor="#8b7765"><table border="0" cellspacing="0" cellpadding="1" width="100%"><tr><td><table border="0" cellspacing="0" cellpadding="1" width="100%" bgcolor="#000000"><tr><td><table border="0" cellpadding="3" cellspacing="1" width="100%"><tr><td bgcolor="#fffacd"><p>Table of Contents:</p><ul><li><a href="FAQ.html#License">License(s)</a></li>
    11. 

  11.   <li><a href="FAQ.html#Installati">Installation</a></li>
    12. 

  12.   <li><a href="FAQ.html#Compilatio">Compilation</a></li>
    13. 

  13.   <li><a href="FAQ.html#Developer">Developer corner</a></li>
    14. 

  14. </ul><h3><a name="License" id="License">License</a>(s)</h3><ol><li><em>Licensing Terms for libxml</em>
    15. 

  15.     <p>libxml2 is released under the <a href="http://www.opensource.org/licenses/mit-license.html">MIT
    16. 

  16.     License</a>; see the file Copyright in the distribution for the precise
    17. 

  17.     wording</p>
    18. 

  18.   </li>
    19. 

  19.   <li><em>Can I embed libxml2 in a proprietary application ?</em>
    20. 

  20.     <p>Yes. The MIT License allows you to keep proprietary the changes you
    21. 

  21.     made to libxml, but it would be graceful to send-back bug fixes and
    22. 

  22.     improvements as patches for possible incorporation in the main
    23. 

  23.     development tree.</p>
    24. 

  24.   </li>
    25. 

  25. </ol><h3><a name="Installati" id="Installati">Installation</a></h3><ol><li><strong><span style="background-color: #FF0000">Do Not Use
    26. 

  26.     libxml1</span></strong>, use libxml2</li>
    27. 

  27.   <p></p>
    28. 

  28.   <li><em>Where can I get libxml</em> ?
    29. 

  29.     <p>The original distribution comes from <a href="ftp://xmlsoft.org/libxml2/">xmlsoft.org</a> or <a href="ftp://ftp.gnome.org/pub/GNOME/sources/libxml2/2.6/">gnome.org</a></p>
    30. 

  30.     <p>Most Linux and BSD distributions include libxml, this is probably the
    31. 

  31.     safer way for end-users to use libxml.</p>
    32. 

  32.     <p>David Doolin provides precompiled Windows versions at <a href="http://www.ce.berkeley.edu/~doolin/code/libxmlwin32/         ">http://www.ce.berkeley.edu/~doolin/code/libxmlwin32/</a></p>
    33. 

  33.   </li>
    34. 

  34.   <p></p>
    35. 

  35.   <li><em>I see libxml and libxml2 releases, which one should I install ?</em>
    36. 

  36.     <ul><li>If you are not constrained by backward compatibility issues with
    37. 

  37.         existing applications, install libxml2 only</li>
    38. 

  38.       <li>If you are not doing development, you can safely install both.
    39. 

  39.         Usually the packages <a href="http://rpmfind.net/linux/RPM/libxml.html">libxml</a> and <a href="http://rpmfind.net/linux/RPM/libxml2.html">libxml2</a> are
    40. 

  40.         compatible (this is not the case for development packages).</li>
    41. 

  41.       <li>If you are a developer and your system provides separate packaging
    42. 

  42.         for shared libraries and the development components, it is possible
    43. 

  43.         to install libxml and libxml2, and also <a href="http://rpmfind.net/linux/RPM/libxml-devel.html">libxml-devel</a>
    44. 

  44.         and <a href="http://rpmfind.net/linux/RPM/libxml2-devel.html">libxml2-devel</a>
    45. 

  45.         too for libxml2 &gt;= 2.3.0</li>
    46. 

  46.       <li>If you are developing a new application, please develop against
    47. 

  47.         libxml2(-devel)</li>
    48. 

  48.     </ul></li>
    49. 

  49.   <li><em>I can't install the libxml package, it conflicts with libxml0</em>
    50. 

  50.     <p>You probably have an old libxml0 package used to provide the shared
    51. 

  51.     library for libxml.so.0, you can probably safely remove it. The libxml
    52. 

  52.     packages provided on <a href="ftp://xmlsoft.org/libxml2/">xmlsoft.org</a> provide
    53. 

  53.     libxml.so.0</p>
    54. 

  54.   </li>
    55. 

  55.   <li><em>I can't install the libxml(2) RPM package due to failed
    56. 

  56.     dependencies</em>
    57. 

  57.     <p>The most generic solution is to re-fetch the latest src.rpm , and
    58. 

  58.     rebuild it locally with</p>
    59. 

  59.     <p><code>rpm --rebuild libxml(2)-xxx.src.rpm</code>.</p>
    60. 

  60.     <p>If everything goes well it will generate two binary rpm packages (one
    61. 

  61.     providing the shared libs and xmllint, and the other one, the -devel
    62. 

  62.     package, providing includes, static libraries and scripts needed to build
    63. 

  63.     applications with libxml(2)) that you can install locally.</p>
    64. 

  64.   </li>
    65. 

  65. </ol><h3><a name="Compilatio" id="Compilatio">Compilation</a></h3><ol><li><em>What is the process to compile libxml2 ?</em>
    66. 

  66.     <p>As most UNIX libraries libxml2 follows the "standard":</p>
    67. 

  67.     <p><code>gunzip -c xxx.tar.gz | tar xvf -</code></p>
    68. 

  68.     <p><code>cd libxml-xxxx</code></p>
    69. 

  69.     <p><code>./configure --help</code></p>
    70. 

  70.     <p>to see the options, then the compilation/installation proper</p>
    71. 

  71.     <p><code>./configure [possible options]</code></p>
    72. 

  72.     <p><code>make</code></p>
    73. 

  73.     <p><code>make install</code></p>
    74. 

  74.     <p>At that point you may have to rerun ldconfig or a similar utility to
    75. 

  75.     update your list of installed shared libs.</p>
    76. 

  76.   </li>
    77. 

  77.   <li><em>What other libraries are needed to compile/install libxml2 ?</em>
    78. 

  78.     <p>Libxml2 does not require any other library, the normal C ANSI API
    79. 

  79.     should be sufficient (please report any violation to this rule you may
    80. 

  80.     find).</p>
    81. 

  81.     <p>However if found at configuration time libxml2 will detect and use the
    82. 

  82.     following libs:</p>
    83. 

  83.     <ul><li><a href="http://www.info-zip.org/pub/infozip/zlib/">libz</a> : a
    84. 

  84.         highly portable and available widely compression library.</li>
    85. 

  85.       <li>iconv: a powerful character encoding conversion library. It is
    86. 

  86.         included by default in recent glibc libraries, so it doesn't need to
    87. 

  87.         be installed specifically on Linux. It now seems a <a href="http://www.opennc.org/onlinepubs/7908799/xsh/iconv.html">part
    88. 

  88.         of the official UNIX</a> specification. Here is one <a href="http://www.gnu.org/software/libiconv/">implementation of the
    89. 

  89.         library</a> which source can be found <a href="ftp://ftp.ilog.fr/pub/Users/haible/gnu/">here</a>.</li>
    90. 

  90.     </ul></li>
    91. 

  91.   <p></p>
    92. 

  92.   <li><em>Make check fails on some platforms</em>
    93. 

  93.     <p>Sometimes the regression tests' results don't completely match the
    94. 

  94.     value produced by the parser, and the makefile uses diff to print the
    95. 

  95.     delta. On some platforms the diff return breaks the compilation process;
    96. 

  96.     if the diff is small this is probably not a serious problem.</p>
    97. 

  97.     <p>Sometimes (especially on Solaris) make checks fail due to limitations
    98. 

  98.     in make. Try using GNU-make instead.</p>
    99. 

  99.   </li>
    100. 

  100.   <li><em>I use the SVN version and there is no configure script</em>
    101. 

  101.     <p>The configure script (and other Makefiles) are generated. Use the
    102. 

  102.     autogen.sh script to regenerate the configure script and Makefiles,
    103. 

  103.     like:</p>
    104. 

  104.     <p><code>./autogen.sh --prefix=/usr --disable-shared</code></p>
    105. 

  105.   </li>
    106. 

  106.   <li><em>I have troubles when running make tests with gcc-3.0</em>
    107. 

  107.     <p>It seems the initial release of gcc-3.0 has a problem with the
    108. 

  108.     optimizer which miscompiles the URI module. Please use another
    109. 

  109.     compiler.</p>
    110. 

  110.   </li>
    111. 

  111. </ol><h3><a name="Developer" id="Developer">Developer</a> corner</h3><ol><li><em>Troubles compiling or linking programs using libxml2</em>
    112. 

  112.     <p>Usually the problem comes from the fact that the compiler doesn't get
    113. 

  113.     the right compilation or linking flags. There is a small shell script
    114. 

  114.     <code>xml2-config</code> which is installed as part of libxml2 usual
    115. 

  115.     install process which provides those flags. Use</p>
    116. 

  116.     <p><code>xml2-config --cflags</code></p>
    117. 

  117.     <p>to get the compilation flags and</p>
    118. 

  118.     <p><code>xml2-config --libs</code></p>
    119. 

  119.     <p>to get the linker flags. Usually this is done directly from the
    120. 

  120.     Makefile as:</p>
    121. 

  121.     <p><code>CFLAGS=`xml2-config --cflags`</code></p>
    122. 

  122.     <p><code>LIBS=`xml2-config --libs`</code></p>
    123. 

  123.   </li>
    124. 

  124.   <li><em>I want to install my own copy of libxml2 in my home directory and
    125. 

  125.     link my programs against it, but it doesn't work</em>
    126. 

  126.     <p>There are many different ways to accomplish this.  Here is one way to
    127. 

  127.     do this under Linux.  Suppose your home directory is <code>/home/user.
    128. 

  128.     </code>Then:</p>
    129. 

  129.     <ul><li>Create a subdirectory, let's call it <code>myxml</code></li>
    130. 

  130.       <li>unpack the libxml2 distribution into that subdirectory</li>
    131. 

  131.       <li>chdir into the unpacked distribution
    132. 

  132.         (<code>/home/user/myxml/libxml2 </code>)</li>
    133. 

  133.       <li>configure the library using the "<code>--prefix</code>" switch,
    134. 

  134.         specifying an installation subdirectory in
    135. 

  135.         <code>/home/user/myxml</code>, e.g.
    136. 

  136.         <p><code>./configure --prefix /home/user/myxml/xmlinst</code> {other
    137. 

  137.         configuration options}</p>
    138. 

  138.       </li>
    139. 

  139.       <li>now run <code>make</code> followed by <code>make install</code></li>
    140. 

  140.       <li>At this point, the installation subdirectory contains the complete
    141. 

  141.         "private" include files, library files and binary program files (e.g.
    142. 

  142.         xmllint), located in
    143. 

  143.         <p><code>/home/user/myxml/xmlinst/lib,
    144. 

  144.         /home/user/myxml/xmlinst/include </code> and <code>
    145. 

  145.         /home/user/myxml/xmlinst/bin</code></p>
    146. 

  146.         respectively.</li>
    147. 

  147.       <li>In order to use this "private" library, you should first add it to
    148. 

  148.         the beginning of your default PATH (so that your own private program
    149. 

  149.         files such as xmllint will be used instead of the normal system
    150. 

  150.         ones).  To do this, the Bash command would be
    151. 

  151.         <p><code>export PATH=/home/user/myxml/xmlinst/bin:$PATH</code></p>
    152. 

  152.       </li>
    153. 

  153.       <li>Now suppose you have a program <code>test1.c</code> that you would
    154. 

  154.         like to compile with your "private" library.  Simply compile it using
    155. 

  155.         the command
    156. 

  156.         <p><code>gcc `xml2-config --cflags --libs` -o test test.c</code></p>
    157. 

  157.         Note that, because your PATH has been set with <code>
    158. 

  158.         /home/user/myxml/xmlinst/bin</code> at the beginning, the xml2-config
    159. 

  159.         program which you just installed will be used instead of the system
    160. 

  160.         default one, and this will <em>automatically</em> get the correct
    161. 

  161.         libraries linked with your program.</li>
    162. 

  162.     </ul></li>
    163. 

  163. 

  164.   <p></p>
    165. 

  165.   <li><em>xmlDocDump() generates output on one line.</em>
    166. 

  166.     <p>Libxml2 will not <strong>invent</strong> spaces in the content of a
    167. 

  167.     document since <strong>all spaces in the content of a document are
    168. 

  168.     significant</strong>. If you build a tree from the API and want
    169. 

  169.     indentation:</p>
    170. 

  170.     <ol><li>the correct way is to generate those yourself too.</li>
    171. 

  171.       <li>the dangerous way is to ask libxml2 to add those blanks to your
    172. 

  172.         content <strong>modifying the content of your document in the
    173. 

  173.         process</strong>. The result may not be what you expect. There is
    174. 

  174.         <strong>NO</strong> way to guarantee that such a modification won't
    175. 

  175.         affect other parts of the content of your document. See <a href="http://xmlsoft.org/html/libxml-parser.html#xmlKeepBlanksDefault">xmlKeepBlanksDefault
    176. 

  176.         ()</a> and <a href="http://xmlsoft.org/html/libxml-tree.html#xmlSaveFormatFile">xmlSaveFormatFile
    177. 

  177.         ()</a></li>
    178. 

  178.     </ol></li>
    179. 

  179.   <p></p>
    180. 

  180.   <li><em>Extra nodes in the document:</em>
    181. 

  181.     <p><em>For an XML file as below:</em></p>
    182. 

  182.     <pre>&lt;?xml version="1.0"?&gt;
    183. 

  183. &lt;PLAN xmlns="http://www.argus.ca/autotest/1.0/"&gt;
    184. 

  184. &lt;NODE CommFlag="0"/&gt;
    185. 

  185. &lt;NODE CommFlag="1"/&gt;
    186. 

  186. &lt;/PLAN&gt;</pre>
    187. 

  187.     <p><em>after parsing it with the function
    188. 

  188.     pxmlDoc=xmlParseFile(...);</em></p>
    189. 

  189.     <p><em>I want to the get the content of the first node (node with the
    190. 

  190.     CommFlag="0")</em></p>
    191. 

  191.     <p><em>so I did it as following;</em></p>
    192. 

  192.     <pre>xmlNodePtr pnode;
    193. 

  193. pnode=pxmlDoc-&gt;children-&gt;children;</pre>
    194. 

  194.     <p><em>but it does not work. If I change it to</em></p>
    195. 

  195.     <pre>pnode=pxmlDoc-&gt;children-&gt;children-&gt;next;</pre>
    196. 

  196.     <p><em>then it works.  Can someone explain it to me.</em></p>
    197. 

  197.     <p></p>
    198. 

  198.     <p>In XML all characters in the content of the document are significant
    199. 

  199.     <strong>including blanks and formatting line breaks</strong>.</p>
    200. 

  200.     <p>The extra nodes you are wondering about are just that, text nodes with
    201. 

  201.     the formatting spaces which are part of the document but that people tend
    202. 

  202.     to forget. There is a function <a href="http://xmlsoft.org/html/libxml-parser.html">xmlKeepBlanksDefault
    203. 

  203.     ()</a>  to remove those at parse time, but that's an heuristic, and its
    204. 

  204.     use should be limited to cases where you are certain there is no
    205. 

  205.     mixed-content in the document.</p>
    206. 

  206.   </li>
    207. 

  207.   <li><em>I get compilation errors of existing code like when accessing
    208. 

  208.     <strong>root</strong> or <strong>child fields</strong> of nodes.</em>
    209. 

  209.     <p>You are compiling code developed for libxml version 1 and using a
    210. 

  210.     libxml2 development environment. Either switch back to libxml v1 devel or
    211. 

  211.     even better fix the code to compile with libxml2 (or both) by <a href="upgrade.html">following the instructions</a>.</p>
    212. 

  212.   </li>
    213. 

  213.   <li><em>I get compilation errors about non existing
    214. 

  214.     <strong>xmlRootNode</strong> or <strong>xmlChildrenNode</strong>
    215. 

  215.     fields.</em>
    216. 

  216.     <p>The source code you are using has been <a href="upgrade.html">upgraded</a> to be able to compile with both libxml
    217. 

  217.     and libxml2, but you need to install a more recent version:
    218. 

  218.     libxml(-devel) &gt;= 1.8.8 or libxml2(-devel) &gt;= 2.1.0</p>
    219. 

  219.   </li>
    220. 

  220.   <li><em>Random crashes in threaded applications</em>
    221. 

  221.     <p>Read and follow all advices on the <a href="threads.html">thread
    222. 

  222.     safety</a> page, and make 100% sure you never call xmlCleanupParser()
    223. 

  223.     while the library or an XML document might still be in use by another
    224. 

  224.     thread.</p>
    225. 

  225.   </li>
    226. 

  226.   <li><em>The example provided in the web page does not compile.</em>
    227. 

  227.     <p>It's hard to maintain the documentation in sync with the code
    228. 

  228.     &lt;grin/&gt; ...</p>
    229. 

  229.     <p>Check the previous points 1/ and 2/ raised before, and please send
    230. 

  230.     patches.</p>
    231. 

  231.   </li>
    232. 

  232.   <li><em>Where can I get more examples and information than provided on the
    233. 

  233.     web page?</em>
    234. 

  234.     <p>Ideally a libxml2 book would be nice. I have no such plan ... But you
    235. 

  235.     can:</p>
    236. 

  236.     <ul><li>check more deeply the <a href="html/libxml-lib.html">existing
    237. 

  237.         generated doc</a></li>
    238. 

  238.       <li>have a look at <a href="examples/index.html">the set of
    239. 

  239.         examples</a>.</li>
    240. 

  240.       <li>look for examples of use for libxml2 function using the Gnome code
    241. 

  241.           or by asking on Google.</li>
    242. 

  242.       <li><a href="http://svn.gnome.org/viewvc/libxml2/trunk/">Browse
    243. 

  243.         the libxml2 source</a> , I try to write code as clean and documented
    244. 

  244.         as possible, so looking at it may be helpful. In particular the code
    245. 

  245.         of <a href="http://svn.gnome.org/viewvc/libxml2/trunk/xmllint.c?view=markup">xmllint.c</a> and of the various testXXX.c test programs should
    246. 

  246.         provide good examples of how to do things with the library.</li>
    247. 

  247.     </ul></li>
    248. 

  248.   <p></p>
    249. 

  249.   <li><em>What about C++ ?</em>
    250. 

  250.     <p>libxml2 is written in pure C in order to allow easy reuse on a number
    251. 

  251.     of platforms, including embedded systems. I don't intend to convert to
    252. 

  252.     C++.</p>
    253. 

  253.     <p>There is however a C++ wrapper which may fulfill your needs:</p>
    254. 

  254.     <ul><li>by Ari Johnson &lt;ari@btigate.com&gt;:
    255. 

  255.         <p>Website: <a href="http://libxmlplusplus.sourceforge.net/">http://libxmlplusplus.sourceforge.net/</a></p>
    256. 

  256.         <p>Download: <a href="http://sourceforge.net/project/showfiles.php?group_id=12999">http://sourceforge.net/project/showfiles.php?group_id=12999</a></p>
    257. 

  257.       </li>
    258. 

  258.     </ul></li>
    259. 

  259.   <li><em>How to validate a document a posteriori ?</em>
    260. 

  260.     <p>It is possible to validate documents which had not been validated at
    261. 

  261.     initial parsing time or documents which have been built from scratch
    262. 

  262.     using the API. Use the <a href="http://xmlsoft.org/html/libxml-valid.html#xmlValidateDtd">xmlValidateDtd()</a>
    263. 

  263.     function. It is also possible to simply add a DTD to an existing
    264. 

  264.     document:</p>
    265. 

  265.     <pre>xmlDocPtr doc; /* your existing document */
    266. 

  266. xmlDtdPtr dtd = xmlParseDTD(NULL, filename_of_dtd); /* parse the DTD */
    267. 

  267. 

  268.         dtd-&gt;name = xmlStrDup((xmlChar*)"root_name"); /* use the given root */
    269. 

  269. 

  270.         doc-&gt;intSubset = dtd;
    271. 

  271.         if (doc-&gt;children == NULL) xmlAddChild((xmlNodePtr)doc, (xmlNodePtr)dtd);
    272. 

  272.         else xmlAddPrevSibling(doc-&gt;children, (xmlNodePtr)dtd);
    273. 

  273.           </pre>
    274. 

  274.   </li>
    275. 

  275.   <li><em>So what is this funky "xmlChar" used all the time?</em>
    276. 

  276.     <p>It is a null terminated sequence of utf-8 characters. And only utf-8!
    277. 

  277.     You need to convert strings encoded in different ways to utf-8 before
    278. 

  278.     passing them to the API.  This can be accomplished with the iconv library
    279. 

  279.     for instance.</p>
    280. 

  280.   </li>
    281. 

  281.   <li>etc ...</li>
    282. 

  282. </ol><p></p><p><a href="bugs.html">Daniel Veillard</a></p></td></tr></table></td></tr></table></td></tr></table></td></tr></table></td></tr></table></body></html>
    283.