<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta charset="utf-8" />
<title>28.2. sysconfig — Provide access to Python’s configuration information — Python 2.7.17 documentation</title>
<link rel="stylesheet" href="../_static/classic.css" type="text/css" />
<link rel="stylesheet" href="../_static/pygments.css" type="text/css" />
<script type="text/javascript" id="documentation_options" data-url_root="../" src="../_static/documentation_options.js"></script>
<script type="text/javascript" src="../_static/jquery.js"></script>
<script type="text/javascript" src="../_static/underscore.js"></script>
<script type="text/javascript" src="../_static/doctools.js"></script>
<script type="text/javascript" src="../_static/language_data.js"></script>
<script type="text/javascript" src="../_static/sidebar.js"></script>
<link rel="search" type="application/opensearchdescription+xml"
title="Search within Python 2.7.17 documentation"
href="../_static/opensearch.xml"/>
<link rel="author" title="About these documents" href="../about.html" />
<link rel="index" title="Index" href="../genindex.html" />
<link rel="search" title="Search" href="../search.html" />
<link rel="copyright" title="Copyright" href="../copyright.html" />
<link rel="next" title="28.3. __builtin__ — Built-in objects" href="__builtin__.html" />
<link rel="prev" title="28.1. sys — System-specific parameters and functions" href="sys.html" />
<link rel="shortcut icon" type="image/png" href="../_static/py.png" />
<link rel="canonical" href="https://docs.python.org/2/library/sysconfig.html" />
<script type="text/javascript" src="../_static/copybutton.js"></script>
</head><body>
<div class="related" role="navigation" aria-label="related navigation">
<h3>Navigation</h3>
<ul>
<li class="right" style="margin-right: 10px">
<a href="../genindex.html" title="General Index"
accesskey="I">index</a></li>
<li class="right" >
<a href="../py-modindex.html" title="Python Module Index"
>modules</a> |</li>
<li class="right" >
<a href="__builtin__.html" title="28.3. __builtin__ — Built-in objects"
accesskey="N">next</a> |</li>
<li class="right" >
<a href="sys.html" title="28.1. sys — System-specific parameters and functions"
accesskey="P">previous</a> |</li>
<li><img src="../_static/py.png" alt=""
style="vertical-align: middle; margin-top: -1px"/></li>
<li><a href="https://www.python.org/">Python</a> »</li>
<li>
<a href="../index.html">Python 2.7.17 documentation</a> »
</li>
<li class="nav-item nav-item-1"><a href="index.html" >The Python Standard Library</a> »</li>
<li class="nav-item nav-item-2"><a href="python.html" accesskey="U">28. Python Runtime Services</a> »</li>
</ul>
</div>
<div class="document">
<div class="documentwrapper">
<div class="bodywrapper">
<div class="body" role="main">
<div class="section" id="module-sysconfig">
<span id="sysconfig-provide-access-to-python-s-configuration-information"></span><h1>28.2. <a class="reference internal" href="#module-sysconfig" title="sysconfig: Python's configuration information"><code class="xref py py-mod docutils literal notranslate"><span class="pre">sysconfig</span></code></a> — Provide access to Python’s configuration information<a class="headerlink" href="#module-sysconfig" title="Permalink to this headline">¶</a></h1>
<div class="versionadded" id="index-0">
<p><span class="versionmodified added">New in version 2.7.</span></p>
</div>
<p><strong>Source code:</strong> <a class="reference external" href="https://github.com/python/cpython/tree/2.7/Lib/sysconfig.py">Lib/sysconfig.py</a></p>
<hr class="docutils" />
<p>The <a class="reference internal" href="#module-sysconfig" title="sysconfig: Python's configuration information"><code class="xref py py-mod docutils literal notranslate"><span class="pre">sysconfig</span></code></a> module provides access to Python’s configuration
information like the list of installation paths and the configuration variables
relevant for the current platform.</p>
<div class="section" id="configuration-variables">
<h2>28.2.1. Configuration variables<a class="headerlink" href="#configuration-variables" title="Permalink to this headline">¶</a></h2>
<p>A Python distribution contains a <code class="file docutils literal notranslate"><span class="pre">Makefile</span></code> and a <code class="file docutils literal notranslate"><span class="pre">pyconfig.h</span></code>
header file that are necessary to build both the Python binary itself and
third-party C extensions compiled using <a class="reference internal" href="distutils.html#module-distutils" title="distutils: Support for building and installing Python modules into an existing Python installation."><code class="xref py py-mod docutils literal notranslate"><span class="pre">distutils</span></code></a>.</p>
<p><a class="reference internal" href="#module-sysconfig" title="sysconfig: Python's configuration information"><code class="xref py py-mod docutils literal notranslate"><span class="pre">sysconfig</span></code></a> puts all variables found in these files in a dictionary that
can be accessed using <a class="reference internal" href="#sysconfig.get_config_vars" title="sysconfig.get_config_vars"><code class="xref py py-func docutils literal notranslate"><span class="pre">get_config_vars()</span></code></a> or <a class="reference internal" href="#sysconfig.get_config_var" title="sysconfig.get_config_var"><code class="xref py py-func docutils literal notranslate"><span class="pre">get_config_var()</span></code></a>.</p>
<p>Notice that on Windows, it’s a much smaller set.</p>
<dl class="function">
<dt id="sysconfig.get_config_vars">
<code class="descclassname">sysconfig.</code><code class="descname">get_config_vars</code><span class="sig-paren">(</span><em>*args</em><span class="sig-paren">)</span><a class="headerlink" href="#sysconfig.get_config_vars" title="Permalink to this definition">¶</a></dt>
<dd><p>With no arguments, return a dictionary of all configuration variables
relevant for the current platform.</p>
<p>With arguments, return a list of values that result from looking up each
argument in the configuration variable dictionary.</p>
<p>For each argument, if the value is not found, return <code class="docutils literal notranslate"><span class="pre">None</span></code>.</p>
</dd></dl>
<dl class="function">
<dt id="sysconfig.get_config_var">
<code class="descclassname">sysconfig.</code><code class="descname">get_config_var</code><span class="sig-paren">(</span><em>name</em><span class="sig-paren">)</span><a class="headerlink" href="#sysconfig.get_config_var" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the value of a single variable <em>name</em>. Equivalent to
<code class="docutils literal notranslate"><span class="pre">get_config_vars().get(name)</span></code>.</p>
<p>If <em>name</em> is not found, return <code class="docutils literal notranslate"><span class="pre">None</span></code>.</p>
</dd></dl>
<p>Example of usage:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">import</span> <span class="nn">sysconfig</span>
<span class="gp">>>> </span><span class="n">sysconfig</span><span class="o">.</span><span class="n">get_config_var</span><span class="p">(</span><span class="s1">'Py_ENABLE_SHARED'</span><span class="p">)</span>
<span class="go">0</span>
<span class="gp">>>> </span><span class="n">sysconfig</span><span class="o">.</span><span class="n">get_config_var</span><span class="p">(</span><span class="s1">'LIBDIR'</span><span class="p">)</span>
<span class="go">'/usr/local/lib'</span>
<span class="gp">>>> </span><span class="n">sysconfig</span><span class="o">.</span><span class="n">get_config_vars</span><span class="p">(</span><span class="s1">'AR'</span><span class="p">,</span> <span class="s1">'CXX'</span><span class="p">)</span>
<span class="go">['ar', 'g++']</span>
</pre></div>
</div>
</div>
<div class="section" id="installation-paths">
<h2>28.2.2. Installation paths<a class="headerlink" href="#installation-paths" title="Permalink to this headline">¶</a></h2>
<p>Python uses an installation scheme that differs depending on the platform and on
the installation options. These schemes are stored in <a class="reference internal" href="#module-sysconfig" title="sysconfig: Python's configuration information"><code class="xref py py-mod docutils literal notranslate"><span class="pre">sysconfig</span></code></a> under
unique identifiers based on the value returned by <a class="reference internal" href="os.html#os.name" title="os.name"><code class="xref py py-const docutils literal notranslate"><span class="pre">os.name</span></code></a>.</p>
<p>Every new component that is installed using <a class="reference internal" href="distutils.html#module-distutils" title="distutils: Support for building and installing Python modules into an existing Python installation."><code class="xref py py-mod docutils literal notranslate"><span class="pre">distutils</span></code></a> or a
Distutils-based system will follow the same scheme to copy its file in the right
places.</p>
<p>Python currently supports seven schemes:</p>
<ul class="simple">
<li><p><em>posix_prefix</em>: scheme for Posix platforms like Linux or Mac OS X. This is
the default scheme used when Python or a component is installed.</p></li>
<li><p><em>posix_home</em>: scheme for Posix platforms used when a <em>home</em> option is used
upon installation. This scheme is used when a component is installed through
Distutils with a specific home prefix.</p></li>
<li><p><em>posix_user</em>: scheme for Posix platforms used when a component is installed
through Distutils and the <em>user</em> option is used. This scheme defines paths
located under the user home directory.</p></li>
<li><p><em>nt</em>: scheme for NT platforms like Windows.</p></li>
<li><p><em>nt_user</em>: scheme for NT platforms, when the <em>user</em> option is used.</p></li>
<li><p><em>os2</em>: scheme for OS/2 platforms.</p></li>
<li><p><em>os2_home</em>: scheme for OS/2 platforms, when the <em>user</em> option is used.</p></li>
</ul>
<p>Each scheme is itself composed of a series of paths and each path has a unique
identifier. Python currently uses eight paths:</p>
<ul class="simple">
<li><p><em>stdlib</em>: directory containing the standard Python library files that are not
platform-specific.</p></li>
<li><p><em>platstdlib</em>: directory containing the standard Python library files that are
platform-specific.</p></li>
<li><p><em>platlib</em>: directory for site-specific, platform-specific files.</p></li>
<li><p><em>purelib</em>: directory for site-specific, non-platform-specific files.</p></li>
<li><p><em>include</em>: directory for non-platform-specific header files.</p></li>
<li><p><em>platinclude</em>: directory for platform-specific header files.</p></li>
<li><p><em>scripts</em>: directory for script files.</p></li>
<li><p><em>data</em>: directory for data files.</p></li>
</ul>
<p><a class="reference internal" href="#module-sysconfig" title="sysconfig: Python's configuration information"><code class="xref py py-mod docutils literal notranslate"><span class="pre">sysconfig</span></code></a> provides some functions to determine these paths.</p>
<dl class="function">
<dt id="sysconfig.get_scheme_names">
<code class="descclassname">sysconfig.</code><code class="descname">get_scheme_names</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#sysconfig.get_scheme_names" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a tuple containing all schemes currently supported in
<a class="reference internal" href="#module-sysconfig" title="sysconfig: Python's configuration information"><code class="xref py py-mod docutils literal notranslate"><span class="pre">sysconfig</span></code></a>.</p>
</dd></dl>
<dl class="function">
<dt id="sysconfig.get_path_names">
<code class="descclassname">sysconfig.</code><code class="descname">get_path_names</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#sysconfig.get_path_names" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a tuple containing all path names currently supported in
<a class="reference internal" href="#module-sysconfig" title="sysconfig: Python's configuration information"><code class="xref py py-mod docutils literal notranslate"><span class="pre">sysconfig</span></code></a>.</p>
</dd></dl>
<dl class="function">
<dt id="sysconfig.get_path">
<code class="descclassname">sysconfig.</code><code class="descname">get_path</code><span class="sig-paren">(</span><em>name</em><span class="optional">[</span>, <em>scheme</em><span class="optional">[</span>, <em>vars</em><span class="optional">[</span>, <em>expand</em><span class="optional">]</span><span class="optional">]</span><span class="optional">]</span><span class="sig-paren">)</span><a class="headerlink" href="#sysconfig.get_path" title="Permalink to this definition">¶</a></dt>
<dd><p>Return an installation path corresponding to the path <em>name</em>, from the
install scheme named <em>scheme</em>.</p>
<p><em>name</em> has to be a value from the list returned by <a class="reference internal" href="#sysconfig.get_path_names" title="sysconfig.get_path_names"><code class="xref py py-func docutils literal notranslate"><span class="pre">get_path_names()</span></code></a>.</p>
<p><a class="reference internal" href="#module-sysconfig" title="sysconfig: Python's configuration information"><code class="xref py py-mod docutils literal notranslate"><span class="pre">sysconfig</span></code></a> stores installation paths corresponding to each path name,
for each platform, with variables to be expanded. For instance the <em>stdlib</em>
path for the <em>nt</em> scheme is: <code class="docutils literal notranslate"><span class="pre">{base}/Lib</span></code>.</p>
<p><a class="reference internal" href="#sysconfig.get_path" title="sysconfig.get_path"><code class="xref py py-func docutils literal notranslate"><span class="pre">get_path()</span></code></a> will use the variables returned by <a class="reference internal" href="#sysconfig.get_config_vars" title="sysconfig.get_config_vars"><code class="xref py py-func docutils literal notranslate"><span class="pre">get_config_vars()</span></code></a>
to expand the path. All variables have default values for each platform so
one may call this function and get the default value.</p>
<p>If <em>scheme</em> is provided, it must be a value from the list returned by
<a class="reference internal" href="#sysconfig.get_scheme_names" title="sysconfig.get_scheme_names"><code class="xref py py-func docutils literal notranslate"><span class="pre">get_scheme_names()</span></code></a>. Otherwise, the default scheme for the current
platform is used.</p>
<p>If <em>vars</em> is provided, it must be a dictionary of variables that will update
the dictionary return by <a class="reference internal" href="#sysconfig.get_config_vars" title="sysconfig.get_config_vars"><code class="xref py py-func docutils literal notranslate"><span class="pre">get_config_vars()</span></code></a>.</p>
<p>If <em>expand</em> is set to <code class="docutils literal notranslate"><span class="pre">False</span></code>, the path will not be expanded using the
variables.</p>
<p>If <em>name</em> is not found, return <code class="docutils literal notranslate"><span class="pre">None</span></code>.</p>
</dd></dl>
<dl class="function">
<dt id="sysconfig.get_paths">
<code class="descclassname">sysconfig.</code><code class="descname">get_paths</code><span class="sig-paren">(</span><span class="optional">[</span><em>scheme</em><span class="optional">[</span>, <em>vars</em><span class="optional">[</span>, <em>expand</em><span class="optional">]</span><span class="optional">]</span><span class="optional">]</span><span class="sig-paren">)</span><a class="headerlink" href="#sysconfig.get_paths" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a dictionary containing all installation paths corresponding to an
installation scheme. See <a class="reference internal" href="#sysconfig.get_path" title="sysconfig.get_path"><code class="xref py py-func docutils literal notranslate"><span class="pre">get_path()</span></code></a> for more information.</p>
<p>If <em>scheme</em> is not provided, will use the default scheme for the current
platform.</p>
<p>If <em>vars</em> is provided, it must be a dictionary of variables that will
update the dictionary used to expand the paths.</p>
<p>If <em>expand</em> is set to false, the paths will not be expanded.</p>
<p>If <em>scheme</em> is not an existing scheme, <a class="reference internal" href="#sysconfig.get_paths" title="sysconfig.get_paths"><code class="xref py py-func docutils literal notranslate"><span class="pre">get_paths()</span></code></a> will raise a
<a class="reference internal" href="exceptions.html#exceptions.KeyError" title="exceptions.KeyError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">KeyError</span></code></a>.</p>
</dd></dl>
</div>
<div class="section" id="other-functions">
<h2>28.2.3. Other functions<a class="headerlink" href="#other-functions" title="Permalink to this headline">¶</a></h2>
<dl class="function">
<dt id="sysconfig.get_python_version">
<code class="descclassname">sysconfig.</code><code class="descname">get_python_version</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#sysconfig.get_python_version" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the <code class="docutils literal notranslate"><span class="pre">MAJOR.MINOR</span></code> Python version number as a string. Similar to
<code class="docutils literal notranslate"><span class="pre">sys.version[:3]</span></code>.</p>
</dd></dl>
<dl class="function">
<dt id="sysconfig.get_platform">
<code class="descclassname">sysconfig.</code><code class="descname">get_platform</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#sysconfig.get_platform" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a string that identifies the current platform.</p>
<p>This is used mainly to distinguish platform-specific build directories and
platform-specific built distributions. Typically includes the OS name and
version and the architecture (as supplied by <a class="reference internal" href="os.html#os.uname" title="os.uname"><code class="xref py py-func docutils literal notranslate"><span class="pre">os.uname()</span></code></a>), although the
exact information included depends on the OS; e.g. for IRIX the architecture
isn’t particularly important (IRIX only runs on SGI hardware), but for Linux
the kernel version isn’t particularly important.</p>
<p>Examples of returned values:</p>
<ul class="simple">
<li><p>linux-i586</p></li>
<li><p>linux-alpha (?)</p></li>
<li><p>solaris-2.6-sun4u</p></li>
<li><p>irix-5.3</p></li>
<li><p>irix64-6.2</p></li>
</ul>
<p>Windows will return one of:</p>
<ul class="simple">
<li><p>win-amd64 (64bit Windows on AMD64, aka x86_64, Intel64, and EM64T)</p></li>
<li><p>win-ia64 (64bit Windows on Itanium)</p></li>
<li><p>win32 (all others - specifically, sys.platform is returned)</p></li>
</ul>
<p>Mac OS X can return:</p>
<ul class="simple">
<li><p>macosx-10.6-ppc</p></li>
<li><p>macosx-10.4-ppc64</p></li>
<li><p>macosx-10.3-i386</p></li>
<li><p>macosx-10.4-fat</p></li>
</ul>
<p>For other non-POSIX platforms, currently just returns <a class="reference internal" href="sys.html#sys.platform" title="sys.platform"><code class="xref py py-data docutils literal notranslate"><span class="pre">sys.platform</span></code></a>.</p>
</dd></dl>
<dl class="function">
<dt id="sysconfig.is_python_build">
<code class="descclassname">sysconfig.</code><code class="descname">is_python_build</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#sysconfig.is_python_build" title="Permalink to this definition">¶</a></dt>
<dd><p>Return <code class="docutils literal notranslate"><span class="pre">True</span></code> if the current Python installation was built from source.</p>
</dd></dl>
<dl class="function">
<dt id="sysconfig.parse_config_h">
<code class="descclassname">sysconfig.</code><code class="descname">parse_config_h</code><span class="sig-paren">(</span><em>fp</em><span class="optional">[</span>, <em>vars</em><span class="optional">]</span><span class="sig-paren">)</span><a class="headerlink" href="#sysconfig.parse_config_h" title="Permalink to this definition">¶</a></dt>
<dd><p>Parse a <code class="file docutils literal notranslate"><span class="pre">config.h</span></code>-style file.</p>
<p><em>fp</em> is a file-like object pointing to the <code class="file docutils literal notranslate"><span class="pre">config.h</span></code>-like file.</p>
<p>A dictionary containing name/value pairs is returned. If an optional
dictionary is passed in as the second argument, it is used instead of a new
dictionary, and updated with the values read in the file.</p>
</dd></dl>
<dl class="function">
<dt id="sysconfig.get_config_h_filename">
<code class="descclassname">sysconfig.</code><code class="descname">get_config_h_filename</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#sysconfig.get_config_h_filename" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the path of <code class="file docutils literal notranslate"><span class="pre">pyconfig.h</span></code>.</p>
</dd></dl>
<dl class="function">
<dt id="sysconfig.get_makefile_filename">
<code class="descclassname">sysconfig.</code><code class="descname">get_makefile_filename</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#sysconfig.get_makefile_filename" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the path of <code class="file docutils literal notranslate"><span class="pre">Makefile</span></code>.</p>
</dd></dl>
</div>
</div>
</div>
</div>
</div>
<div class="sphinxsidebar" role="navigation" aria-label="main navigation">
<div class="sphinxsidebarwrapper">
<h3><a href="../contents.html">Table of Contents</a></h3>
<ul>
<li><a class="reference internal" href="#">28.2. <code class="xref py py-mod docutils literal notranslate"><span class="pre">sysconfig</span></code> — Provide access to Python’s configuration information</a><ul>
<li><a class="reference internal" href="#configuration-variables">28.2.1. Configuration variables</a></li>
<li><a class="reference internal" href="#installation-paths">28.2.2. Installation paths</a></li>
<li><a class="reference internal" href="#other-functions">28.2.3. Other functions</a></li>
</ul>
</li>
</ul>
<h4>Previous topic</h4>
<p class="topless"><a href="sys.html"
title="previous chapter">28.1. <code class="xref py py-mod docutils literal notranslate"><span class="pre">sys</span></code> — System-specific parameters and functions</a></p>
<h4>Next topic</h4>
<p class="topless"><a href="__builtin__.html"
title="next chapter">28.3. <code class="xref py py-mod docutils literal notranslate"><span class="pre">__builtin__</span></code> — Built-in objects</a></p>
<div role="note" aria-label="source link">
<h3>This Page</h3>
<ul class="this-page-menu">
<li><a href="../_sources/library/sysconfig.rst.txt"
rel="nofollow">Show Source</a></li>
</ul>
</div>
<div id="searchbox" style="display: none" role="search">
<h3>Quick search</h3>
<div class="searchformwrapper">
<form class="search" action="../search.html" method="get">
<input type="text" name="q" />
<input type="submit" value="Go" />
</form>
</div>
</div>
<script type="text/javascript">$('#searchbox').show(0);</script>
</div>
</div>
<div class="clearer"></div>
</div>
<div class="related" role="navigation" aria-label="related navigation">
<h3>Navigation</h3>
<ul>
<li class="right" style="margin-right: 10px">
<a href="../genindex.html" title="General Index"
>index</a></li>
<li class="right" >
<a href="../py-modindex.html" title="Python Module Index"
>modules</a> |</li>
<li class="right" >
<a href="__builtin__.html" title="28.3. __builtin__ — Built-in objects"
>next</a> |</li>
<li class="right" >
<a href="sys.html" title="28.1. sys — System-specific parameters and functions"
>previous</a> |</li>
<li><img src="../_static/py.png" alt=""
style="vertical-align: middle; margin-top: -1px"/></li>
<li><a href="https://www.python.org/">Python</a> »</li>
<li>
<a href="../index.html">Python 2.7.17 documentation</a> »
</li>
<li class="nav-item nav-item-1"><a href="index.html" >The Python Standard Library</a> »</li>
<li class="nav-item nav-item-2"><a href="python.html" >28. Python Runtime Services</a> »</li>
</ul>
</div>
<div class="footer">
© <a href="../copyright.html">Copyright</a> 1990-2019, Python Software Foundation.
<br />
The Python Software Foundation is a non-profit corporation.
<a href="https://www.python.org/psf/donations/">Please donate.</a>
<br />
Last updated on Oct 19, 2019.
<a href="../bugs.html">Found a bug</a>?
<br />
Created using <a href="http://sphinx.pocoo.org/">Sphinx</a> 2.0.1.
</div>
</body>
</html>
distrib
>
Mageia
>
7
>
armv7hl
>
media
>
core-updates
>
by-pkgid
>
e1011ddec34cda34f3a002b121247943
>
files
>
941
