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diff --git a/doc/FAQ.html b/doc/FAQ.html index 0d5ded6..cdc6585 100644 --- a/doc/FAQ.html +++ b/doc/FAQ.html @@ -12,53 +12,49 @@ A:link, A:visited, A:active { text-decoration: underline } <li><a href="FAQ.html#Compilatio">Compilation</a></li> <li><a href="FAQ.html#Developer">Developer corner</a></li> </ul><h3><a name="License" id="License">License</a>(s)</h3><ol><li><em>Licensing Terms for libxml</em> - <p>libxml2 is released under the <a href="http://www.opensource.org/licenses/mit-license.html">MIT - License</a>; see the file Copyright in the distribution for the precise - wording</p> + <p>libxml2 is released under the <a href="http://www.opensource.org/licenses/mit-license.html">MITLicense</a>;see + the file Copyright in the distribution for the precisewording</p> </li> <li><em>Can I embed libxml2 in a proprietary application ?</em> - <p>Yes. The MIT License allows you to keep proprietary the changes you - made to libxml, but it would be graceful to send-back bug fixes and - improvements as patches for possible incorporation in the main - development tree.</p> + <p>Yes. The MIT License allows you to keep proprietary the changesyoumade + to libxml, but it would be graceful to send-back bug fixesandimprovements + as patches for possible incorporation in themaindevelopment tree.</p> </li> -</ol><h3><a name="Installati" id="Installati">Installation</a></h3><ol><li><strong><span style="background-color: #FF0000">Do Not Use - libxml1</span></strong>, use libxml2</li> - <li><em>Where can I get libxml</em> ? - <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> - <p>Most Linux and BSD distributions include libxml, this is probably the - safer way for end-users to use libxml.</p> +</ol><h3><a name="Installati" id="Installati">Installation</a></h3><ol><li><strong><span style="background-color: #FF0000">Do + NotUselibxml1</span></strong>, use libxml2</li> + <li><em>Where can I get libxml</em>? + <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> + <p>Most Linux and BSD distributions include libxml, this is + probablythesafer way for end-users to use libxml.</p> <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> </li> <li><em>I see libxml and libxml2 releases, which one should I install ?</em> - <ul><li>If you are not constrained by backward compatibility issues with - existing applications, install libxml2 only</li> - <li>If you are not doing development, you can safely install both. - 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 - compatible (this is not the case for development packages).</li> - <li>If you are a developer and your system provides separate packaging - for shared libraries and the development components, it is possible - to install libxml and libxml2, and also <a href="http://rpmfind.net/linux/RPM/libxml-devel.html">libxml-devel</a> - and <a href="http://rpmfind.net/linux/RPM/libxml2-devel.html">libxml2-devel</a> - too for libxml2 >= 2.3.0</li> - <li>If you are developing a new application, please develop against - libxml2(-devel)</li> + <ul><li>If you are not constrained by backward compatibility + issueswithexisting applications, install libxml2 only</li> + <li>If you are not doing development, you can safely + installboth.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>arecompatible(this + is not the case for development packages).</li> + <li>If you are a developer and your system provides + separatepackagingfor shared libraries and the development components, + it ispossibleto install libxml and libxml2, and also <a href="http://rpmfind.net/linux/RPM/libxml-devel.html">libxml-devel</a>and<a href="http://rpmfind.net/linux/RPM/libxml2-devel.html">libxml2-devel</a>toofor + libxml2 >= 2.3.0</li> + <li>If you are developing a new application, please + developagainstlibxml2(-devel)</li> </ul></li> <li><em>I can't install the libxml package, it conflicts with libxml0</em> - <p>You probably have an old libxml0 package used to provide the shared - library for libxml.so.0, you can probably safely remove it. The libxml - packages provided on <a href="ftp://xmlsoft.org/libxml2/">xmlsoft.org</a> provide - libxml.so.0</p> + <p>You probably have an old libxml0 package used to provide + thesharedlibrary for libxml.so.0, you can probably safely remove it. + Thelibxmlpackages provided on <a href="ftp://xmlsoft.org/libxml2/">xmlsoft.org</a>providelibxml.so.0</p> </li> - <li><em>I can't install the libxml(2) RPM package due to failed - dependencies</em> - <p>The most generic solution is to re-fetch the latest src.rpm , and - rebuild it locally with</p> + <li><em>I can't install the libxml(2) RPM package due + tofaileddependencies</em> + <p>The most generic solution is to re-fetch the latest src.rpm + ,andrebuild it locally with</p> <p><code>rpm --rebuild libxml(2)-xxx.src.rpm</code>.</p> - <p>If everything goes well it will generate two binary rpm packages (one - providing the shared libs and xmllint, and the other one, the -devel - package, providing includes, static libraries and scripts needed to build - applications with libxml(2)) that you can install locally.</p> + <p>If everything goes well it will generate two binary rpm + packages(oneproviding the shared libs and xmllint, and the other one, + the-develpackage, providing includes, static libraries and scripts needed + tobuildapplications with libxml(2)) that you can install locally.</p> </li> </ol><h3><a name="Compilatio" id="Compilatio">Compilation</a></h3><ol><li><em>What is the process to compile libxml2 ?</em> <p>As most UNIX libraries libxml2 follows the "standard":</p> @@ -69,109 +65,106 @@ A:link, A:visited, A:active { text-decoration: underline } <p><code>./configure [possible options]</code></p> <p><code>make</code></p> <p><code>make install</code></p> - <p>At that point you may have to rerun ldconfig or a similar utility to - update your list of installed shared libs.</p> + <p>At that point you may have to rerun ldconfig or a similar + utilitytoupdate your list of installed shared libs.</p> </li> <li><em>What other libraries are needed to compile/install libxml2 ?</em> - <p>Libxml2 does not require any other library, the normal C ANSI API - should be sufficient (please report any violation to this rule you may - find).</p> - <p>However if found at configuration time libxml2 will detect and use the - following libs:</p> - <ul><li><a href="http://www.info-zip.org/pub/infozip/zlib/">libz</a> : a - highly portable and available widely compression library.</li> - <li>iconv: a powerful character encoding conversion library. It is - included by default in recent glibc libraries, so it doesn't need to - be installed specifically on Linux. It now seems a <a href="http://www.opennc.org/onlinepubs/7908799/xsh/iconv.html">part - of the official UNIX</a> specification. Here is one <a href="http://www.gnu.org/software/libiconv/">implementation of the - library</a> which source can be found <a href="ftp://ftp.ilog.fr/pub/Users/haible/gnu/">here</a>.</li> + <p>Libxml2 does not require any other library, the normal C ANSIAPIshould + be sufficient (please report any violation to this rule youmayfind).</p> + <p>However if found at configuration time libxml2 will detect and + usethefollowing libs:</p> + <ul><li><a href="http://www.info-zip.org/pub/infozip/zlib/">libz</a>:ahighly + portable and available widely compression library.</li> + <li>iconv: a powerful character encoding conversion library. + Itisincluded by default in recent glibc libraries, so it doesn't + needtobe installed specifically on Linux. It now seems a <a href="http://www.opennc.org/onlinepubs/7908799/xsh/iconv.html">partofthe + official UNIX</a>specification. Here is one <a href="http://www.gnu.org/software/libiconv/">implementation + ofthelibrary</a>which source can be found <a href="ftp://ftp.ilog.fr/pub/Users/haible/gnu/">here</a>.</li> </ul></li> <li><em>Make check fails on some platforms</em> - <p>Sometimes the regression tests' results don't completely match the - value produced by the parser, and the makefile uses diff to print the - delta. On some platforms the diff return breaks the compilation process; - if the diff is small this is probably not a serious problem.</p> - <p>Sometimes (especially on Solaris) make checks fail due to limitations - in make. Try using GNU-make instead.</p> + <p>Sometimes the regression tests' results don't completely matchthevalue + produced by the parser, and the makefile uses diff to printthedelta. On + some platforms the diff return breaks the compilationprocess;if the diff + is small this is probably not a serious problem.</p> + <p>Sometimes (especially on Solaris) make checks fail due tolimitationsin + make. Try using GNU-make instead.</p> </li> <li><em>I use the CVS version and there is no configure script</em> - <p>The configure script (and other Makefiles) are generated. Use the - autogen.sh script to regenerate the configure script and Makefiles, - like:</p> + <p>The configure script (and other Makefiles) are generated. + Usetheautogen.sh script to regenerate the configure script + andMakefiles,like:</p> <p><code>./autogen.sh --prefix=/usr --disable-shared</code></p> </li> <li><em>I have troubles when running make tests with gcc-3.0</em> - <p>It seems the initial release of gcc-3.0 has a problem with the - optimizer which miscompiles the URI module. Please use another - compiler.</p> + <p>It seems the initial release of gcc-3.0 has a problem withtheoptimizer + which miscompiles the URI module. Please useanothercompiler.</p> </li> -</ol><h3><a name="Developer" id="Developer">Developer</a> corner</h3><ol><li><em>Troubles compiling or linking programs using libxml2</em> - <p>Usually the problem comes from the fact that the compiler doesn't get - the right compilation or linking flags. There is a small shell script - <code>xml2-config</code> which is installed as part of libxml2 usual - install process which provides those flags. Use</p> +</ol><h3><a name="Developer" id="Developer">Developer</a>corner</h3><ol><li><em>Troubles compiling or linking programs using libxml2</em> + <p>Usually the problem comes from the fact that the compiler + doesn'tgetthe right compilation or linking flags. There is a small + shellscript<code>xml2-config</code>which is installed as part of + libxml2usualinstall process which provides those flags. Use</p> <p><code>xml2-config --cflags</code></p> <p>to get the compilation flags and</p> <p><code>xml2-config --libs</code></p> - <p>to get the linker flags. Usually this is done directly from the - Makefile as:</p> + <p>to get the linker flags. Usually this is done directly fromtheMakefile + as:</p> <p><code>CFLAGS=`xml2-config --cflags`</code></p> <p><code>LIBS=`xml2-config --libs`</code></p> </li> - <li><em>I want to install my own copy of libxml2 in my home directory and - link my programs against it, but it doesn't work</em> - <p>There are many different ways to accomplish this. Here is one way to - do this under Linux. Suppose your home directory is <code>/home/user. - </code>Then:</p> + <li><em>I want to install my own copy of libxml2 in my home + directoryandlink my programs against it, but it doesn't work</em> + <p>There are many different ways to accomplish this. Here is one waytodo + this under Linux. Suppose your home directory + is<code>/home/user.</code>Then:</p> <ul><li>Create a subdirectory, let's call it <code>myxml</code></li> <li>unpack the libxml2 distribution into that subdirectory</li> - <li>chdir into the unpacked distribution - (<code>/home/user/myxml/libxml2 </code>)</li> - <li>configure the library using the "<code>--prefix</code>" switch, - specifying an installation subdirectory in - <code>/home/user/myxml</code>, e.g. - <p><code>./configure --prefix /home/user/myxml/xmlinst</code> {other - configuration options}</p> + <li>chdir into the unpacked + distribution(<code>/home/user/myxml/libxml2</code>)</li> + <li>configure the library using the + "<code>--prefix</code>"switch,specifying an installation + subdirectoryin<code>/home/user/myxml</code>, e.g. + <p><code>./configure + --prefix/home/user/myxml/xmlinst</code>{otherconfiguration + options}</p> </li> - <li>now run <code>make</code> followed by <code>make install</code></li> - <li>At this point, the installation subdirectory contains the complete - "private" include files, library files and binary program files (e.g. - xmllint), located in - <p><code>/home/user/myxml/xmlinst/lib, - /home/user/myxml/xmlinst/include </code> and <code> - /home/user/myxml/xmlinst/bin</code></p> + <li>now run <code>make</code>followed by <code>make install</code></li> + <li>At this point, the installation subdirectory contains + thecomplete"private" include files, library files and binary + programfiles (e.g.xmllint), located in + <p><code>/home/user/myxml/xmlinst/lib,/home/user/myxml/xmlinst/include</code>and + <code>/home/user/myxml/xmlinst/bin</code></p> respectively.</li> - <li>In order to use this "private" library, you should first add it to - the beginning of your default PATH (so that your own private program - files such as xmllint will be used instead of the normal system - ones). To do this, the Bash command would be + <li>In order to use this "private" library, you should first add + ittothe beginning of your default PATH (so that your own + privateprogramfiles such as xmllint will be used instead of the + normalsystemones). To do this, the Bash command would be <p><code>export PATH=/home/user/myxml/xmlinst/bin:$PATH</code></p> </li> - <li>Now suppose you have a program <code>test1.c</code> that you would - like to compile with your "private" library. Simply compile it using - the command + <li>Now suppose you have a program <code>test1.c</code>that + youwouldlike to compile with your "private" library. Simply compile + itusingthe command <p><code>gcc `xml2-config --cflags --libs` -o test test.c</code></p> - Note that, because your PATH has been set with <code> - /home/user/myxml/xmlinst/bin</code> at the beginning, the xml2-config - program which you just installed will be used instead of the system - default one, and this will <em>automatically</em> get the correct - libraries linked with your program.</li> + Note that, because your PATH has been set + with<code>/home/user/myxml/xmlinst/bin</code>at the beginning, + thexml2-configprogram which you just installed will be used instead + ofthe systemdefault one, and this will <em>automatically</em>get + thecorrectlibraries linked with your program.</li> </ul></li> <p></p> <li><em>xmlDocDump() generates output on one line.</em> - <p>Libxml2 will not <strong>invent</strong> spaces in the content of a - document since <strong>all spaces in the content of a document are - significant</strong>. If you build a tree from the API and want - indentation:</p> + <p>Libxml2 will not <strong>invent</strong>spaces in the content + ofadocument since <strong>all spaces in the content of a + documentaresignificant</strong>. If you build a tree from the API + andwantindentation:</p> <ol><li>the correct way is to generate those yourself too.</li> - <li>the dangerous way is to ask libxml2 to add those blanks to your - content <strong>modifying the content of your document in the - process</strong>. The result may not be what you expect. There is - <strong>NO</strong> way to guarantee that such a modification won't - affect other parts of the content of your document. See <a href="http://xmlsoft.org/html/libxml-parser.html#xmlKeepBlanksDefault">xmlKeepBlanksDefault - ()</a> and <a href="http://xmlsoft.org/html/libxml-tree.html#xmlSaveFormatFile">xmlSaveFormatFile - ()</a></li> + <li>the dangerous way is to ask libxml2 to add those blanks + toyourcontent <strong>modifying the content of your document + intheprocess</strong>. The result may not be what you expect. + Thereis<strong>NO</strong>way to guarantee that such a + modificationwon'taffect other parts of the content of your document. + See <a href="http://xmlsoft.org/html/libxml-parser.html#xmlKeepBlanksDefault">xmlKeepBlanksDefault()</a>and<a href="http://xmlsoft.org/html/libxml-tree.html#xmlSaveFormatFile">xmlSaveFormatFile()</a></li> </ol></li> <li>Extra nodes in the document: <p><em>For a XML file as below:</em></p> @@ -180,10 +173,10 @@ A:link, A:visited, A:active { text-decoration: underline } <NODE CommFlag="0"/> <NODE CommFlag="1"/> </PLAN></pre> - <p><em>after parsing it with the function - pxmlDoc=xmlParseFile(...);</em></p> - <p><em>I want to the get the content of the first node (node with the - CommFlag="0")</em></p> + <p><em>after parsing it with + thefunctionpxmlDoc=xmlParseFile(...);</em></p> + <p><em>I want to the get the content of the first node (node + withtheCommFlag="0")</em></p> <p><em>so I did it as following;</em></p> <pre>xmlNodePtr pnode; pnode=pxmlDoc->children->children;</pre> @@ -191,63 +184,62 @@ pnode=pxmlDoc->children->children;</pre> <pre>pnode=pxmlDoc->children->children->next;</pre> <p><em>then it works. Can someone explain it to me.</em></p> <p></p> - <p>In XML all characters in the content of the document are significant - <strong>including blanks and formatting line breaks</strong>.</p> - <p>The extra nodes you are wondering about are just that, text nodes with - the formatting spaces which are part of the document but that people tend - to forget. There is a function <a href="http://xmlsoft.org/html/libxml-parser.html">xmlKeepBlanksDefault - ()</a> to remove those at parse time, but that's an heuristic, and its - use should be limited to cases where you are certain there is no - mixed-content in the document.</p> + <p>In XML all characters in the content of the document + aresignificant<strong>including blanks and formatting + linebreaks</strong>.</p> + <p>The extra nodes you are wondering about are just that, text + nodeswiththe formatting spaces which are part of the document but that + peopletendto forget. There is a function <a href="http://xmlsoft.org/html/libxml-parser.html">xmlKeepBlanksDefault()</a>toremove + those at parse time, but that's an heuristic, and itsuse should belimited + to cases where you are certain there is nomixed-content in + thedocument.</p> </li> - <li><em>I get compilation errors of existing code like when accessing - <strong>root</strong> or <strong>child fields</strong> of nodes.</em> - <p>You are compiling code developed for libxml version 1 and using a - libxml2 development environment. Either switch back to libxml v1 devel or - even better fix the code to compile with libxml2 (or both) by <a href="upgrade.html">following the instructions</a>.</p> + <li><em>I get compilation errors of existing code like + whenaccessing<strong>root</strong>or <strong>child + fields</strong>ofnodes.</em> + <p>You are compiling code developed for libxml version 1 and + usingalibxml2 development environment. Either switch back to libxml v1 + develoreven better fix the code to compile with libxml2 (or both) by <a href="upgrade.html">following the instructions</a>.</p> </li> - <li><em>I get compilation errors about non existing - <strong>xmlRootNode</strong> or <strong>xmlChildrenNode</strong> - fields.</em> - <p>The source code you are using has been <a href="upgrade.html">upgraded</a> to be able to compile with both libxml - and libxml2, but you need to install a more recent version: - libxml(-devel) >= 1.8.8 or libxml2(-devel) >= 2.1.0</p> + <li><em>I get compilation errors about + nonexisting<strong>xmlRootNode</strong>or<strong>xmlChildrenNode</strong>fields.</em> + <p>The source code you are using has been <a href="upgrade.html">upgraded</a>to be able to compile with both + libxmlandlibxml2, but you need to install a more recent + version:libxml(-devel)>= 1.8.8 or libxml2(-devel) >= 2.1.0</p> </li> <li><em>XPath implementation looks seriously broken</em> - <p>XPath implementation prior to 2.3.0 was really incomplete. Upgrade to - a recent version, there are no known bugs in the current version.</p> + <p>XPath implementation prior to 2.3.0 was really incomplete. Upgrade + toarecent version, there are no known bugs in the current version.</p> </li> <li><em>The example provided in the web page does not compile.</em> - <p>It's hard to maintain the documentation in sync with the code - <grin/> ...</p> - <p>Check the previous points 1/ and 2/ raised before, and please send - patches.</p> + <p>It's hard to maintain the documentation in sync with + thecode<grin/> ...</p> + <p>Check the previous points 1/ and 2/ raised before, and + pleasesendpatches.</p> </li> - <li><em>Where can I get more examples and information than provided on the - web page?</em> - <p>Ideally a libxml2 book would be nice. I have no such plan ... But you - can:</p> - <ul><li>check more deeply the <a href="html/libxml-lib.html">existing - generated doc</a></li> - <li>have a look at <a href="examples/index.html">the set of - examples</a>.</li> - <li>look for examples of use for libxml2 function using the Gnome code. - For example the following will query the full Gnome CVS base for the - use of the <strong>xmlAddChild()</strong> function: + <li><em>Where can I get more examples and information than provided + ontheweb page?</em> + <p>Ideally a libxml2 book would be nice. I have no such plan ... + Butyoucan:</p> + <ul><li>check more deeply the <a href="html/libxml-lib.html">existinggenerated doc</a></li> + <li>have a look at <a href="examples/index.html">the + setofexamples</a>.</li> + <li>look for examples of use for libxml2 function using the + Gnomecode.For example the following will query the full Gnome CVS + base fortheuse of the <strong>xmlAddChild()</strong>function: <p><a href="http://cvs.gnome.org/lxr/search?string=xmlAddChild">http://cvs.gnome.org/lxr/search?string=xmlAddChild</a></p> - <p>This may be slow, a large hardware donation to the gnome project - could cure this :-)</p> + <p>This may be slow, a large hardware donation to the + gnomeprojectcould cure this :-)</p> </li> - <li><a href="http://cvs.gnome.org/bonsai/rview.cgi?cvsroot=/cvs/gnome&dir=gnome-xml">Browse - the libxml2 source</a> , I try to write code as clean and documented - as possible, so looking at it may be helpful. In particular the code - of xmllint.c and of the various testXXX.c test programs should - provide good examples of how to do things with the library.</li> + <li><a href="http://cvs.gnome.org/bonsai/rview.cgi?cvsroot=/cvs/gnome&dir=gnome-xml">Browsethelibxml2 + source</a>, I try to write code as clean and documentedaspossible, so + looking at it may be helpful. In particular the codeofxmllint.c and + of the various testXXX.c test programs shouldprovidegood examples of + how to do things with the library.</li> </ul></li> <li>What about C++ ? - <p>libxml2 is written in pure C in order to allow easy reuse on a number - of platforms, including embedded systems. I don't intend to convert to - C++.</p> + <p>libxml2 is written in pure C in order to allow easy reuse on anumberof + platforms, including embedded systems. I don't intend to converttoC++.</p> <p>There is however a C++ wrapper which may fulfill your needs:</p> <ul><li>by Ari Johnson <ari@btigate.com>: <p>Website: <a href="http://libxmlplusplus.sourceforge.net/">http://libxmlplusplus.sourceforge.net/</a></p> @@ -261,11 +253,10 @@ pnode=pxmlDoc->children->children;</pre> --> </ul></li> <li>How to validate a document a posteriori ? - <p>It is possible to validate documents which had not been validated at - initial parsing time or documents which have been built from scratch - using the API. Use the <a href="http://xmlsoft.org/html/libxml-valid.html#xmlValidateDtd">xmlValidateDtd()</a> - function. It is also possible to simply add a DTD to an existing - document:</p> + <p>It is possible to validate documents which had not been + validatedatinitial parsing time or documents which have been built + fromscratchusing the API. Use the <a href="http://xmlsoft.org/html/libxml-valid.html#xmlValidateDtd">xmlValidateDtd()</a>function.It + is also possible to simply add a DTD to an existingdocument:</p> <pre>xmlDocPtr doc; /* your existing document */ xmlDtdPtr dtd = xmlParseDTD(NULL, filename_of_dtd); /* parse the DTD */ @@ -277,10 +268,10 @@ xmlDtdPtr dtd = xmlParseDTD(NULL, filename_of_dtd); /* parse the DTD */ </pre> </li> <li>So what is this funky "xmlChar" used all the time? - <p>It is a null terminated sequence of utf-8 characters. And only utf-8! - You need to convert strings encoded in different ways to utf-8 before - passing them to the API. This can be accomplished with the iconv library - for instance.</p> + <p>It is a null terminated sequence of utf-8 characters. And + onlyutf-8!You need to convert strings encoded in different ways to + utf-8beforepassing them to the API. This can be accomplished with the + iconvlibraryfor instance.</p> </li> <li>etc ...</li> </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> |