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+:mod:`sysconfig` --- Provide access to Python's configuration information
+=========================================================================
+
+.. module:: sysconfig
+ :synopsis: Python's configuration information
+.. moduleauthor:: Tarek Ziade <tarek@ziade.org>
+.. sectionauthor:: Tarek Ziade <tarek@ziade.org>
+.. versionadded:: 2.7
+.. index::
+ single: configuration information
+
+The :mod:`sysconfig` module provides access to Python's configuration
+information like the list of installation paths and the configuration variables
+relevant for the current platform.
+
+Configuration variables
+-----------------------
+
+A Python distribution contains a :file:`Makefile` and a :file:`pyconfig.h`
+header file that are necessary to build both the Python binary itself and
+third-party C extensions compiled using :mod:`distutils`.
+
+:mod:`sysconfig` puts all variables found in these files in a dictionary that
+can be accessed using :func:`get_config_vars` or :func:`get_config_var`.
+
+Notice that on Windows, it's a much smaller set.
+
+.. function:: get_config_vars(\*args)
+
+ With no arguments, return a dictionary of all configuration variables
+ relevant for the current platform.
+
+ With arguments, return a list of values that result from looking up each
+ argument in the configuration variable dictionary.
+
+ For each argument, if the value is not found, return ``None``.
+
+
+.. function:: get_config_var(name)
+
+ Return the value of a single variable *name*. Equivalent to
+ ``get_config_vars().get(name)``.
+
+ If *name* is not found, return ``None``.
+
+Example of usage::
+
+ >>> import sysconfig
+ >>> sysconfig.get_config_var('Py_ENABLE_SHARED')
+ 0
+ >>> sysconfig.get_config_var('LIBDIR')
+ '/usr/local/lib'
+ >>> sysconfig.get_config_vars('AR', 'CXX')
+ ['ar', 'g++']
+
+
+Installation paths
+------------------
+
+Python uses an installation scheme that differs depending on the platform and on
+the installation options. These schemes are stored in :mod:`sysconfig` under
+unique identifiers based on the value returned by :const:`os.name`.
+
+Every new component that is installed using :mod:`distutils` or a
+Distutils-based system will follow the same scheme to copy its file in the right
+places.
+
+Python currently supports seven schemes:
+
+- *posix_prefix*: scheme for Posix platforms like Linux or Mac OS X. This is
+ the default scheme used when Python or a component is installed.
+- *posix_home*: scheme for Posix platforms used when a *home* option is used
+ upon installation. This scheme is used when a component is installed through
+ Distutils with a specific home prefix.
+- *posix_user*: scheme for Posix platforms used when a component is installed
+ through Distutils and the *user* option is used. This scheme defines paths
+ located under the user home directory.
+- *nt*: scheme for NT platforms like Windows.
+- *nt_user*: scheme for NT platforms, when the *user* option is used.
+- *os2*: scheme for OS/2 platforms.
+- *os2_home*: scheme for OS/2 patforms, when the *user* option is used.
+
+Each scheme is itself composed of a series of paths and each path has a unique
+identifier. Python currently uses eight paths:
+
+- *stdlib*: directory containing the standard Python library files that are not
+ platform-specific.
+- *platstdlib*: directory containing the standard Python library files that are
+ platform-specific.
+- *platlib*: directory for site-specific, platform-specific files.
+- *purelib*: directory for site-specific, non-platform-specific files.
+- *include*: directory for non-platform-specific header files.
+- *platinclude*: directory for platform-specific header files.
+- *scripts*: directory for script files.
+- *data*: directory for data files.
+
+:mod:`sysconfig` provides some functions to determine these paths.
+
+.. function:: get_scheme_names()
+
+ Return a tuple containing all schemes currently supported in
+ :mod:`sysconfig`.
+
+
+.. function:: get_path_names()
+
+ Return a tuple containing all path names currently supported in
+ :mod:`sysconfig`.
+
+
+.. function:: get_path(name, [scheme, [vars, [expand]]])
+
+ Return an installation path corresponding to the path *name*, from the
+ install scheme named *scheme*.
+
+ *name* has to be a value from the list returned by :func:`get_path_names`.
+
+ :mod:`sysconfig` stores installation paths corresponding to each path name,
+ for each platform, with variables to be expanded. For instance the *stdlib*
+ path for the *nt* scheme is: ``{base}/Lib``.
+
+ :func:`get_path` will use the variables returned by :func:`get_config_vars`
+ to expand the path. All variables have default values for each platform so
+ one may call this function and get the default value.
+
+ If *scheme* is provided, it must be a value from the list returned by
+ :func:`get_path_names`. Otherwise, the default scheme for the current
+ platform is used.
+
+ If *vars* is provided, it must be a dictionary of variables that will update
+ the dictionary return by :func:`get_config_vars`.
+
+ If *expand* is set to ``False``, the path will not be expanded using the
+ variables.
+
+ If *name* is not found, return ``None``.
+
+
+.. function:: get_paths([scheme, [vars, [expand]]])
+
+ Return a dictionary containing all installation paths corresponding to an
+ installation scheme. See :func:`get_path` for more information.
+
+ If *scheme* is not provided, will use the default scheme for the current
+ platform.
+
+ If *vars* is provided, it must be a dictionary of variables that will
+ update the dictionary used to expand the paths.
+
+ If *expand* is set to False, the paths will not be expanded.
+
+ If *scheme* is not an existing scheme, :func:`get_paths` will raise a
+ :exc:`KeyError`.
+
+
+Other functions
+---------------
+
+.. function:: get_python_version()
+
+ Return the ``MAJOR.MINOR`` Python version number as a string. Similar to
+ ``sys.version[:3]``.
+
+
+.. function:: get_platform()
+
+ Return a string that identifies the current platform.
+
+ 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 :func:`os.uname`), 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.
+
+ Examples of returned values:
+
+ - linux-i586
+ - linux-alpha (?)
+ - solaris-2.6-sun4u
+ - irix-5.3
+ - irix64-6.2
+
+ Windows will return one of:
+
+ - win-amd64 (64bit Windows on AMD64 (aka x86_64, Intel64, EM64T, etc)
+ - win-ia64 (64bit Windows on Itanium)
+ - win32 (all others - specifically, sys.platform is returned)
+
+ Mac OS X can return:
+
+ - macosx-10.6-ppc
+ - macosx-10.4-ppc64
+ - macosx-10.3-i386
+ - macosx-10.4-fat
+
+ For other non-POSIX platforms, currently just returns :data:`sys.platform`.
+
+
+.. function:: is_python_build()
+
+ Return ``True`` if the current Python installation was built from source.
+
+
+.. function:: parse_config_h(fp[, vars])
+
+ Parse a :file:`config.h`\-style file.
+
+ *fp* is a file-like object pointing to the :file:`config.h`\-like file.
+
+ 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.
+
+
+.. function:: get_config_h_filename()
+
+ Return the path of :file:`pyconfig.h`.