doc/html/installation.html

   1 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
   2 <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
   3 <head>
   4 <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
   5 <meta name="generator" content="Docutils 0.14: http://docutils.sourceforge.net/" />
   6 <title>Installing lxml</title>
   7 <link rel="stylesheet" href="style.css" type="text/css" />
   8 <script type="text/javascript">
   9 function trigger_menu(event) {
  10     var sidemenu = document.getElementById("sidemenu");
  11     var classes = sidemenu.getAttribute("class");
  12     classes = (classes.indexOf(" visible") === -1) ? classes + " visible" : classes.replace(" visible", "");
  13     sidemenu.setAttribute("class", classes);
  14     event.preventDefault();
  15     event.stopPropagation();
  16 }
  17 function hide_menu() {
  18     var sidemenu = document.getElementById("sidemenu");
  19     var classes = sidemenu.getAttribute("class");
  20     if (classes.indexOf(" visible") !== -1) {
  21         sidemenu.setAttribute("class", classes.replace(" visible", ""));
  22     }
  23 }
  24 </script><meta content="width=device-width, initial-scale=1" name="viewport" /></head>
  25 <body onclick="hide_menu()">
  26 <div class="document" id="installing-lxml">
  27 <div class="sidemenu" id="sidemenu"><div class="menutrigger" onclick="trigger_menu(event)">Menu</div><div class="menu"><ul id="lxml-section"><li><span class="section title">lxml</span><ul class="menu foreign" id="index-menu"><li class="menu title"><a href="index.html">lxml</a><ul class="submenu"><li class="menu item"><a href="index.html#introduction">Introduction</a></li><li class="menu item"><a href="index.html#support-the-project">Support the project</a></li><li class="menu item"><a href="index.html#documentation">Documentation</a></li><li class="menu item"><a href="index.html#download">Download</a></li><li class="menu item"><a href="index.html#mailing-list">Mailing list</a></li><li class="menu item"><a href="index.html#bug-tracker">Bug tracker</a></li><li class="menu item"><a href="index.html#license">License</a></li><li class="menu item"><a href="index.html#old-versions">Old Versions</a></li><li class="menu item"><a href="index.html#legal-notice-for-donations">Legal Notice for Donations</a></li></ul></li></ul><ul class="menu foreign" id="intro-menu"><li class="menu title"><a href="intro.html">Why lxml?</a><ul class="submenu"><li class="menu item"><a href="intro.html#motto">Motto</a></li><li class="menu item"><a href="intro.html#aims">Aims</a></li></ul></li></ul><ul class="menu current" id="installation-menu"><li class="menu title"><a href="installation.html">Installing lxml</a><ul class="submenu"><li class="menu item"><a href="installation.html#where-to-get-it">Where to get it</a></li><li class="menu item"><a href="installation.html#requirements">Requirements</a></li><li class="menu item"><a href="installation.html#installation">Installation</a></li><li class="menu item"><a href="installation.html#building-lxml-from-dev-sources">Building lxml from dev sources</a></li><li class="menu item"><a href="installation.html#using-lxml-with-python-libxml2">Using lxml with python-libxml2</a></li><li class="menu item"><a href="installation.html#source-builds-on-ms-windows">Source builds on MS Windows</a></li><li class="menu item"><a href="installation.html#source-builds-on-macos-x">Source builds on MacOS-X</a></li></ul></li></ul><ul class="menu foreign" id="performance-menu"><li class="menu title"><a href="performance.html">Benchmarks and Speed</a><ul class="submenu"><li class="menu item"><a href="performance.html#general-notes">General notes</a></li><li class="menu item"><a href="performance.html#how-to-read-the-timings">How to read the timings</a></li><li class="menu item"><a href="performance.html#parsing-and-serialising">Parsing and Serialising</a></li><li class="menu item"><a href="performance.html#the-elementtree-api">The ElementTree API</a></li><li class="menu item"><a href="performance.html#xpath">XPath</a></li><li class="menu item"><a href="performance.html#a-longer-example">A longer example</a></li><li class="menu item"><a href="performance.html#lxml-objectify">lxml.objectify</a></li></ul></li></ul><ul class="menu foreign" id="compatibility-menu"><li class="menu title"><a href="compatibility.html">ElementTree compatibility of lxml.etree</a></li></ul><ul class="menu foreign" id="FAQ-menu"><li class="menu title"><a href="FAQ.html">lxml FAQ - Frequently Asked Questions</a><ul class="submenu"><li class="menu item"><a href="FAQ.html#general-questions">General Questions</a></li><li class="menu item"><a href="FAQ.html#installation">Installation</a></li><li class="menu item"><a href="FAQ.html#contributing">Contributing</a></li><li class="menu item"><a href="FAQ.html#bugs">Bugs</a></li><li class="menu item"><a href="FAQ.html#id1">Threading</a></li><li class="menu item"><a href="FAQ.html#parsing-and-serialisation">Parsing and Serialisation</a></li><li class="menu item"><a href="FAQ.html#xpath-and-document-traversal">XPath and Document Traversal</a></li></ul></li></ul></li></ul><ul id="Developing with lxml-section"><li><span class="section title">Developing with lxml</span><ul class="menu foreign" id="tutorial-menu"><li class="menu title"><a href="tutorial.html">The lxml.etree Tutorial</a><ul class="submenu"><li class="menu item"><a href="tutorial.html#the-element-class">The Element class</a></li><li class="menu item"><a href="tutorial.html#the-elementtree-class">The ElementTree class</a></li><li class="menu item"><a href="tutorial.html#parsing-from-strings-and-files">Parsing from strings and files</a></li><li class="menu item"><a href="tutorial.html#namespaces">Namespaces</a></li><li class="menu item"><a href="tutorial.html#the-e-factory">The E-factory</a></li><li class="menu item"><a href="tutorial.html#elementpath">ElementPath</a></li></ul></li></ul><ul class="menu foreign" id="api index-menu"><li class="menu title"><a href="api/index.html">API reference</a></li></ul><ul class="menu foreign" id="api-menu"><li class="menu title"><a href="api.html">APIs specific to lxml.etree</a><ul class="submenu"><li class="menu item"><a href="api.html#lxml-etree">lxml.etree</a></li><li class="menu item"><a href="api.html#other-element-apis">Other Element APIs</a></li><li class="menu item"><a href="api.html#trees-and-documents">Trees and Documents</a></li><li class="menu item"><a href="api.html#iteration">Iteration</a></li><li class="menu item"><a href="api.html#error-handling-on-exceptions">Error handling on exceptions</a></li><li class="menu item"><a href="api.html#error-logging">Error logging</a></li><li class="menu item"><a href="api.html#serialisation">Serialisation</a></li><li class="menu item"><a href="api.html#incremental-xml-generation">Incremental XML generation</a></li><li class="menu item"><a href="api.html#cdata">CDATA</a></li><li class="menu item"><a href="api.html#xinclude-and-elementinclude">XInclude and ElementInclude</a></li></ul></li></ul><ul class="menu foreign" id="parsing-menu"><li class="menu title"><a href="parsing.html">Parsing XML and HTML with lxml</a><ul class="submenu"><li class="menu item"><a href="parsing.html#parsers">Parsers</a></li><li class="menu item"><a href="parsing.html#the-target-parser-interface">The target parser interface</a></li><li class="menu item"><a href="parsing.html#the-feed-parser-interface">The feed parser interface</a></li><li class="menu item"><a href="parsing.html#incremental-event-parsing">Incremental event parsing</a></li><li class="menu item"><a href="parsing.html#iterparse-and-iterwalk">iterparse and iterwalk</a></li><li class="menu item"><a href="parsing.html#python-unicode-strings">Python unicode strings</a></li></ul></li></ul><ul class="menu foreign" id="validation-menu"><li class="menu title"><a href="validation.html">Validation with lxml</a><ul class="submenu"><li class="menu item"><a href="validation.html#validation-at-parse-time">Validation at parse time</a></li><li class="menu item"><a href="validation.html#id1">DTD</a></li><li class="menu item"><a href="validation.html#relaxng">RelaxNG</a></li><li class="menu item"><a href="validation.html#xmlschema">XMLSchema</a></li><li class="menu item"><a href="validation.html#id2">Schematron</a></li><li class="menu item"><a href="validation.html#id3">(Pre-ISO-Schematron)</a></li></ul></li></ul><ul class="menu foreign" id="xpathxslt-menu"><li class="menu title"><a href="xpathxslt.html">XPath and XSLT with lxml</a><ul class="submenu"><li class="menu item"><a href="xpathxslt.html#xpath">XPath</a></li><li class="menu item"><a href="xpathxslt.html#xslt">XSLT</a></li></ul></li></ul><ul class="menu foreign" id="objectify-menu"><li class="menu title"><a href="objectify.html">lxml.objectify</a><ul class="submenu"><li class="menu item"><a href="objectify.html#the-lxml-objectify-api">The lxml.objectify API</a></li><li class="menu item"><a href="objectify.html#asserting-a-schema">Asserting a Schema</a></li><li class="menu item"><a href="objectify.html#objectpath">ObjectPath</a></li><li class="menu item"><a href="objectify.html#python-data-types">Python data types</a></li><li class="menu item"><a href="objectify.html#how-data-types-are-matched">How data types are matched</a></li><li class="menu item"><a href="objectify.html#what-is-different-from-lxml-etree">What is different from lxml.etree?</a></li></ul></li></ul><ul class="menu foreign" id="lxmlhtml-menu"><li class="menu title"><a href="lxmlhtml.html">lxml.html</a><ul class="submenu"><li class="menu item"><a href="lxmlhtml.html#parsing-html">Parsing HTML</a></li><li class="menu item"><a href="lxmlhtml.html#html-element-methods">HTML Element Methods</a></li><li class="menu item"><a href="lxmlhtml.html#running-html-doctests">Running HTML doctests</a></li><li class="menu item"><a href="lxmlhtml.html#creating-html-with-the-e-factory">Creating HTML with the E-factory</a></li><li class="menu item"><a href="lxmlhtml.html#working-with-links">Working with links</a></li><li class="menu item"><a href="lxmlhtml.html#forms">Forms</a></li><li class="menu item"><a href="lxmlhtml.html#cleaning-up-html">Cleaning up HTML</a></li><li class="menu item"><a href="lxmlhtml.html#html-diff">HTML Diff</a></li><li class="menu item"><a href="lxmlhtml.html#examples">Examples</a></li></ul></li></ul><ul class="menu foreign" id="cssselect-menu"><li class="menu title"><a href="cssselect.html">lxml.cssselect</a><ul class="submenu"><li class="menu item"><a href="cssselect.html#the-cssselector-class">The CSSSelector class</a></li><li class="menu item"><a href="cssselect.html#the-cssselect-method">The cssselect method</a></li><li class="menu item"><a href="cssselect.html#supported-selectors">Supported Selectors</a></li><li class="menu item"><a href="cssselect.html#namespaces">Namespaces</a></li></ul></li></ul><ul class="menu foreign" id="elementsoup-menu"><li class="menu title"><a href="elementsoup.html">BeautifulSoup Parser</a><ul class="submenu"><li class="menu item"><a href="elementsoup.html#parsing-with-the-soupparser">Parsing with the soupparser</a></li><li class="menu item"><a href="elementsoup.html#entity-handling">Entity handling</a></li><li class="menu item"><a href="elementsoup.html#using-soupparser-as-a-fallback">Using soupparser as a fallback</a></li><li class="menu item"><a href="elementsoup.html#using-only-the-encoding-detection">Using only the encoding detection</a></li></ul></li></ul><ul class="menu foreign" id="html5parser-menu"><li class="menu title"><a href="html5parser.html">html5lib Parser</a><ul class="submenu"><li class="menu item"><a href="html5parser.html#differences-to-regular-html-parsing">Differences to regular HTML parsing</a></li><li class="menu item"><a href="html5parser.html#function-reference">Function Reference</a></li></ul></li></ul></li></ul><ul id="Extending lxml-section"><li><span class="section title">Extending lxml</span><ul class="menu foreign" id="resolvers-menu"><li class="menu title"><a href="resolvers.html">Document loading and URL resolving</a><ul class="submenu"><li class="menu item"><a href="resolvers.html#xml-catalogs">XML Catalogs</a></li><li class="menu item"><a href="resolvers.html#uri-resolvers">URI Resolvers</a></li><li class="menu item"><a href="resolvers.html#document-loading-in-context">Document loading in context</a></li><li class="menu item"><a href="resolvers.html#i-o-access-control-in-xslt">I/O access control in XSLT</a></li></ul></li></ul><ul class="menu foreign" id="extensions-menu"><li class="menu title"><a href="extensions.html">Python extensions for XPath and XSLT</a><ul class="submenu"><li class="menu item"><a href="extensions.html#xpath-extension-functions">XPath Extension functions</a></li><li class="menu item"><a href="extensions.html#xslt-extension-elements">XSLT extension elements</a></li></ul></li></ul><ul class="menu foreign" id="element classes-menu"><li class="menu title"><a href="element_classes.html">Using custom Element classes in lxml</a><ul class="submenu"><li class="menu item"><a href="element_classes.html#background-on-element-proxies">Background on Element proxies</a></li><li class="menu item"><a href="element_classes.html#element-initialization">Element initialization</a></li><li class="menu item"><a href="element_classes.html#setting-up-a-class-lookup-scheme">Setting up a class lookup scheme</a></li><li class="menu item"><a href="element_classes.html#generating-xml-with-custom-classes">Generating XML with custom classes</a></li><li class="menu item"><a href="element_classes.html#id1">Implementing namespaces</a></li></ul></li></ul><ul class="menu foreign" id="sax-menu"><li class="menu title"><a href="sax.html">Sax support</a><ul class="submenu"><li class="menu item"><a href="sax.html#building-a-tree-from-sax-events">Building a tree from SAX events</a></li><li class="menu item"><a href="sax.html#producing-sax-events-from-an-elementtree-or-element">Producing SAX events from an ElementTree or Element</a></li><li class="menu item"><a href="sax.html#interfacing-with-pulldom-minidom">Interfacing with pulldom/minidom</a></li></ul></li></ul><ul class="menu foreign" id="capi-menu"><li class="menu title"><a href="capi.html">The public C-API of lxml.etree</a><ul class="submenu"><li class="menu item"><a href="capi.html#passing-generated-trees-through-python">Passing generated trees through Python</a></li><li class="menu item"><a href="capi.html#writing-external-modules-in-cython">Writing external modules in Cython</a></li><li class="menu item"><a href="capi.html#writing-external-modules-in-c">Writing external modules in C</a></li></ul></li></ul></li></ul><ul id="Developing lxml-section"><li><span class="section title">Developing lxml</span><ul class="menu foreign" id="build-menu"><li class="menu title"><a href="build.html">How to build lxml from source</a><ul class="submenu"><li class="menu item"><a href="build.html#cython">Cython</a></li><li class="menu item"><a href="build.html#github-git-and-hg">Github, git and hg</a></li><li class="menu item"><a href="build.html#building-the-sources">Building the sources</a></li><li class="menu item"><a href="build.html#running-the-tests-and-reporting-errors">Running the tests and reporting errors</a></li><li class="menu item"><a href="build.html#building-an-egg-or-wheel">Building an egg or wheel</a></li><li class="menu item"><a href="build.html#building-lxml-on-macos-x">Building lxml on MacOS-X</a></li><li class="menu item"><a href="build.html#static-linking-on-windows">Static linking on Windows</a></li><li class="menu item"><a href="build.html#building-debian-packages-from-svn-sources">Building Debian packages from SVN sources</a></li></ul></li></ul><ul class="menu foreign" id="lxml source howto-menu"><li class="menu title"><a href="lxml-source-howto.html">How to read the source of lxml</a><ul class="submenu"><li class="menu item"><a href="lxml-source-howto.html#what-is-cython">What is Cython?</a></li><li class="menu item"><a href="lxml-source-howto.html#where-to-start">Where to start?</a></li><li class="menu item"><a href="lxml-source-howto.html#lxml-etree">lxml.etree</a></li><li class="menu item"><a href="lxml-source-howto.html#python-modules">Python modules</a></li><li class="menu item"><a href="lxml-source-howto.html#lxml-objectify">lxml.objectify</a></li><li class="menu item"><a href="lxml-source-howto.html#lxml-html">lxml.html</a></li></ul></li></ul><ul class="menu foreign" id="changes 4 4 3-menu"><li class="menu title"><a href="changes-4.4.3.html">Release Changelog</a></li></ul><ul class="menu foreign" id="credits-menu"><li class="menu title"><a href="credits.html">Credits</a><ul class="submenu"><li class="menu item"><a href="credits.html#main-contributors">Main contributors</a></li><li class="menu item"><a href="credits.html#special-thanks-goes-to">Special thanks goes to:</a></li></ul></li></ul></li><li><a href="/sitemap.html">Sitemap</a></li></ul></div></div><h1 class="title">Installing lxml</h1>
  28
  29 <div class="contents topic" id="contents">
  30 <p class="topic-title first">Contents</p>
  31 <ul class="simple">
  32 <li><a class="reference internal" href="#where-to-get-it" id="id1">Where to get it</a></li>
  33 <li><a class="reference internal" href="#requirements" id="id2">Requirements</a></li>
  34 <li><a class="reference internal" href="#installation" id="id3">Installation</a></li>
  35 <li><a class="reference internal" href="#building-lxml-from-dev-sources" id="id4">Building lxml from dev sources</a></li>
  36 <li><a class="reference internal" href="#using-lxml-with-python-libxml2" id="id5">Using lxml with python-libxml2</a></li>
  37 <li><a class="reference internal" href="#source-builds-on-ms-windows" id="id6">Source builds on MS Windows</a></li>
  38 <li><a class="reference internal" href="#source-builds-on-macos-x" id="id7">Source builds on MacOS-X</a></li>
  39 </ul>
  40 </div>
  41 <div class="section" id="where-to-get-it">
  42 <h1>Where to get it</h1>
  43 <p>lxml is generally distributed through <a class="reference external" href="http://pypi.python.org/pypi/lxml">PyPI</a>.</p>
  44 <p>Most <strong>Linux</strong> platforms come with some version of lxml readily
  45 packaged, usually named <tt class="docutils literal"><span class="pre">python-lxml</span></tt> for the Python 2.x version
  46 and <tt class="docutils literal"><span class="pre">python3-lxml</span></tt> for Python 3.x.  If you can use that version,
  47 the quickest way to install lxml is to use the system package
  48 manager, e.g. <tt class="docutils literal"><span class="pre">apt-get</span></tt> on Debian/Ubuntu:</p>
  49 <pre class="literal-block">
  50 sudo apt-get install python3-lxml
  51 </pre>
  52 <p>For <strong>MacOS-X</strong>, a <a class="reference external" href="http://macports.org/">macport</a> of lxml is available.
  53 Try something like</p>
  54 <pre class="literal-block">
  55 sudo port install py27-lxml
  56 </pre>
  57 <p>To install a newer version or to install lxml on other systems,
  58 see below.</p>
  59 </div>
  60 <div class="section" id="requirements">
  61 <h1>Requirements</h1>
  62 <p>You need Python 2.7 or 3.4+.</p>
  63 <p>Unless you are using a static binary distribution (e.g. from a
  64 Windows binary installer), lxml requires libxml2 and libxslt to
  65 be installed, in particular:</p>
  66 <ul class="simple">
  67 <li><a class="reference external" href="http://xmlsoft.org/">libxml2</a> version 2.9.2 or later.</li>
  68 <li><a class="reference external" href="http://xmlsoft.org/XSLT/">libxslt</a> version 1.1.27 or later.<ul>
  69 <li>We recommend libxslt 1.1.28 or later.</li>
  70 </ul>
  71 </li>
  72 </ul>
  73 <p>Newer versions generally contain fewer bugs and are therefore
  74 recommended.  XML Schema support is also still worked on in libxml2,
  75 so newer versions will give you better compliance with the W3C spec.</p>
  76 <p>To install the required development packages of these dependencies
  77 on Linux systems, use your distribution specific installation tool,
  78 e.g. apt-get on Debian/Ubuntu:</p>
  79 <pre class="literal-block">
  80 sudo apt-get install libxml2-dev libxslt-dev python-dev
  81 </pre>
  82 <p>For Debian based systems, it should be enough to install the known
  83 build dependencies of the provided lxml package, e.g.</p>
  84 <pre class="literal-block">
  85 sudo apt-get build-dep python3-lxml
  86 </pre>
  87 </div>
  88 <div class="section" id="installation">
  89 <h1>Installation</h1>
  90 <p>If your system does not provide binary packages or you want to install
  91 a newer version, the best way is to get the <a class="reference external" href="http://pypi.python.org/pypi/pip">pip</a> package management tool
  92 (or use a <a class="reference external" href="https://pypi.python.org/pypi/virtualenv">virtualenv</a>) and
  93 run the following:</p>
  94 <pre class="literal-block">
  95 pip install lxml
  96 </pre>
  97 <p>If you are not using pip in a virtualenv and want to install lxml globally
  98 instead, you have to run the above command as admin, e.g. on Linux:</p>
  99 <pre class="literal-block">
 100 sudo pip install lxml
 101 </pre>
 102 <p>To install a specific version, either download the distribution
 103 manually and let pip install that, or pass the desired version
 104 to pip:</p>
 105 <pre class="literal-block">
 106 pip install lxml==3.4.2
 107 </pre>
 108 <p>To speed up the build in test environments, e.g. on a continuous
 109 integration server, disable the C compiler optimisations by setting
 110 the <tt class="docutils literal">CFLAGS</tt> environment variable:</p>
 111 <pre class="literal-block">
 112 CFLAGS="-O0"  pip install lxml
 113 </pre>
 114 <p>(The option reads "minus Oh Zero", i.e. zero optimisations.)</p>
 115 <div class="section" id="ms-windows">
 116 <h2>MS Windows</h2>
 117 <p>For MS Windows, recent lxml releases feature community donated
 118 binary distributions, although you might still want to take a look
 119 at the related <a class="reference external" href="FAQ.html#where-are-the-binary-builds">FAQ entry</a>.
 120 If you fail to build lxml on your MS Windows system from the signed
 121 and tested sources that we release, consider using the binary builds
 122 from PyPI or the <a class="reference external" href="http://www.lfd.uci.edu/~gohlke/pythonlibs/#lxml">unofficial Windows binaries</a>
 123 that Christoph Gohlke generously provides.</p>
 124 </div>
 125 <div class="section" id="linux">
 126 <h2>Linux</h2>
 127 <p>On Linux (and most other well-behaved operating systems), <tt class="docutils literal">pip</tt> will
 128 manage to build the source distribution as long as libxml2 and libxslt
 129 are properly installed, including development packages, i.e. header files,
 130 etc.  See the requirements section above and use your system package
 131 management tool to look for packages like <tt class="docutils literal"><span class="pre">libxml2-dev</span></tt> or
 132 <tt class="docutils literal"><span class="pre">libxslt-devel</span></tt>.  If the build fails, make sure they are installed.</p>
 133 <p>Alternatively, setting <tt class="docutils literal">STATIC_DEPS=true</tt> will download and build
 134 both libraries automatically in their latest version, e.g.
 135 <tt class="docutils literal">STATIC_DEPS=true pip install lxml</tt>.</p>
 136 </div>
 137 <div class="section" id="macos-x">
 138 <h2>MacOS-X</h2>
 139 <p>On MacOS-X, use the following to build the source distribution,
 140 and make sure you have a working Internet connection, as this will
 141 download libxml2 and libxslt in order to build them:</p>
 142 <pre class="literal-block">
 143 STATIC_DEPS=true sudo pip install lxml
 144 </pre>
 145 </div>
 146 </div>
 147 <div class="section" id="building-lxml-from-dev-sources">
 148 <h1>Building lxml from dev sources</h1>
 149 <p>If you want to build lxml from the GitHub repository, you should read
 150 <a class="reference external" href="build.html">how to build lxml from source</a> (or the file <tt class="docutils literal">doc/build.txt</tt> in the
 151 source tree).  Building from developer sources or from modified
 152 distribution sources requires <a class="reference external" href="http://www.cython.org">Cython</a> to translate the lxml sources
 153 into C code.  The source distribution ships with pre-generated C
 154 source files, so you do not need Cython installed to build from
 155 release sources.</p>
 156 <p>If you have read these instructions and still cannot manage to install lxml,
 157 you can check the archives of the <a class="reference external" href="http://lxml.de/mailinglist/">mailing list</a> to see if your problem is
 158 known or otherwise send a mail to the list.</p>
 159 </div>
 160 <div class="section" id="using-lxml-with-python-libxml2">
 161 <h1>Using lxml with python-libxml2</h1>
 162 <p>If you want to use lxml together with the official libxml2 Python
 163 bindings (maybe because one of your dependencies uses it), you must
 164 build lxml statically.  Otherwise, the two packages will interfere in
 165 places where the libxml2 library requires global configuration, which
 166 can have any kind of effect from disappearing functionality to crashes
 167 in either of the two.</p>
 168 <p>To get a static build, either pass the <tt class="docutils literal"><span class="pre">--static-deps</span></tt> option to the
 169 setup.py script, or run <tt class="docutils literal">pip</tt> with the <tt class="docutils literal">STATIC_DEPS</tt> or
 170 <tt class="docutils literal">STATICBUILD</tt> environment variable set to true, i.e.</p>
 171 <pre class="literal-block">
 172 STATIC_DEPS=true pip install lxml
 173 </pre>
 174 <p>The <tt class="docutils literal">STATICBUILD</tt> environment variable is handled equivalently to
 175 the <tt class="docutils literal">STATIC_DEPS</tt> variable, but is used by some other extension
 176 packages, too.</p>
 177 </div>
 178 <div class="section" id="source-builds-on-ms-windows">
 179 <h1>Source builds on MS Windows</h1>
 180 <p>Most MS Windows systems lack the necessarily tools to build software,
 181 starting with a C compiler already.  Microsoft leaves it to users to
 182 install and configure them, which is usually not trivial and means
 183 that distributors cannot rely on these dependencies being available
 184 on a given system.  In a way, you get what you've paid for and make
 185 others pay for it.</p>
 186 <p>Due to the additional lack of package management of this platform,
 187 it is best to link the library dependencies statically if you decide
 188 to build from sources, rather than using a binary installer.  For
 189 that, lxml can use the <a class="reference external" href="http://www.zlatkovic.com/libxml.en.html">binary distribution of libxml2 and libxslt</a>, which it downloads
 190 automatically during the static build.  It needs both libxml2 and
 191 libxslt, as well as iconv and zlib, which are available from the
 192 same download site.  Further build instructions are in the
 193 <a class="reference external" href="build.html">source build documentation</a>.</p>
 194 </div>
 195 <div class="section" id="source-builds-on-macos-x">
 196 <h1>Source builds on MacOS-X</h1>
 197 <p>If you are not using macports or want to use a more recent lxml
 198 release, you have to build it yourself.  While the pre-installed system
 199 libraries of libxml2 and libxslt are less outdated in recent MacOS-X
 200 versions than they used to be, so lxml should work with them out of the
 201 box, it is still recommended to use a static build with the most recent
 202 library versions.</p>
 203 <p>Luckily, lxml's <tt class="docutils literal">setup.py</tt> script has built-in support for building
 204 and integrating these libraries statically during the build.  Please
 205 read the
 206 <a class="reference external" href="build.html#building-lxml-on-macos-x">MacOS-X build instructions</a>.</p>
 207 </div>
 208 </div>
 209 <div class="footer">
 210 <hr class="footer" />
 211 Generated on: 2020-01-29.
 212
 213 </div>
 214 </body>
 215 </html>