diff --git a/Doc/library/site.rst b/Doc/library/site.rst index ebd78917a01..02880c56416 100644 --- a/Doc/library/site.rst +++ b/Doc/library/site.rst @@ -199,7 +199,7 @@ Module contents :file:`~/Library/Python/{X.Y}` for macOS framework builds, and :file:`{%APPDATA%}\\Python` for Windows. This value is used to compute the installation directories for scripts, data files, Python modules, - etc. for the user installation scheme. + etc. for the :ref:`user installation scheme `. See also :envvar:`PYTHONUSERBASE`. diff --git a/Doc/library/sysconfig.rst b/Doc/library/sysconfig.rst index c625c1e1d72..905abc3a7c9 100644 --- a/Doc/library/sysconfig.rst +++ b/Doc/library/sysconfig.rst @@ -20,6 +20,7 @@ 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 ----------------------- @@ -60,6 +61,7 @@ Example of usage:: >>> sysconfig.get_config_vars('AR', 'CXX') ['ar', 'g++'] + .. _installation_paths: Installation paths @@ -68,27 +70,24 @@ 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. +The schemes are used by package installers to determine where to copy files to. Python currently supports nine schemes: - *posix_prefix*: scheme for POSIX platforms like Linux or macOS. 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. +- *posix_home*: scheme for POSIX platforms, when the *home* option is used. + This scheme defines paths located under a specific home prefix. +- *posix_user*: scheme for POSIX platforms, when the *user* option is used. + This scheme defines paths located under the user's home directory + (:const:`site.USER_BASE`). - *posix_venv*: scheme for :mod:`Python virtual environments ` on POSIX platforms; by default it is the same as *posix_prefix*. -- *nt*: scheme for NT platforms like Windows. -- *nt_user*: scheme for NT platforms, when the *user* option is used. -- *nt_venv*: scheme for :mod:`Python virtual environments ` on NT - platforms; by default it is the same as *nt*. +- *nt*: scheme for Windows. + This is the default scheme used when Python or a component is installed. +- *nt_user*: scheme for Windows, when the *user* option is used. +- *nt_venv*: scheme for :mod:`Python virtual environments ` on Windows; + by default it is the same as *nt*. - *venv*: a scheme with values from either *posix_venv* or *nt_venv* depending on the platform Python runs on. - *osx_framework_user*: scheme for macOS, when the *user* option is used. @@ -101,7 +100,7 @@ identifier. Python currently uses eight paths: - *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. +- *purelib*: directory for site-specific, non-platform-specific files ('pure' Python). - *include*: directory for non-platform-specific header files for the Python C-API. - *platinclude*: directory for platform-specific header files for @@ -109,7 +108,157 @@ identifier. Python currently uses eight paths: - *scripts*: directory for script files. - *data*: directory for data files. -:mod:`sysconfig` provides some functions to determine these paths. + +.. _sysconfig-user-scheme: + +User scheme +--------------- + +This scheme is designed to be the most convenient solution for users that don't +have write permission to the global site-packages directory or don't want to +install into it. + +Files will be installed into subdirectories of :const:`site.USER_BASE` (written +as :file:`{userbase}` hereafter). This scheme installs pure Python modules and +extension modules in the same location (also known as :const:`site.USER_SITE`). + +``posix_user`` +^^^^^^^^^^^^^^ + +============== =========================================================== +Path Installation directory +============== =========================================================== +*stdlib* :file:`{userbase}/lib/python{X.Y}` +*platstdlib* :file:`{userbase}/lib/python{X.Y}` +*platlib* :file:`{userbase}/lib/python{X.Y}/site-packages` +*purelib* :file:`{userbase}/lib/python{X.Y}/site-packages` +*include* :file:`{userbase}/include/python{X.Y}` +*scripts* :file:`{userbase}/bin` +*data* :file:`{userbase}` +============== =========================================================== + +``nt_user`` +^^^^^^^^^^^ + +============== =========================================================== +Path Installation directory +============== =========================================================== +*stdlib* :file:`{userbase}\\Python{XY}` +*platstdlib* :file:`{userbase}\\Python{XY}` +*platlib* :file:`{userbase}\\Python{XY}\\site-packages` +*purelib* :file:`{userbase}\\Python{XY}\\site-packages` +*include* :file:`{userbase}\\Python{XY}\\Include` +*scripts* :file:`{userbase}\\Python{XY}\\Scripts` +*data* :file:`{userbase}` +============== =========================================================== + +``osx_framework_user`` +^^^^^^^^^^^^^^^^^^^^^^ + +============== =========================================================== +Path Installation directory +============== =========================================================== +*stdlib* :file:`{userbase}/lib/python` +*platstdlib* :file:`{userbase}/lib/python` +*platlib* :file:`{userbase}/lib/python/site-packages` +*purelib* :file:`{userbase}/lib/python/site-packages` +*include* :file:`{userbase}/include/python{X.Y}` +*scripts* :file:`{userbase}/bin` +*data* :file:`{userbase}` +============== =========================================================== + + +.. _sysconfig-home-scheme: + +Home scheme +----------- + +The idea behind the "home scheme" is that you build and maintain a personal +stash of Python modules. This scheme's name is derived from the idea of a +"home" directory on Unix, since it's not unusual for a Unix user to make their +home directory have a layout similar to :file:`/usr/` or :file:`/usr/local/`. +This scheme can be used by anyone, regardless of the operating system they +are installing for. + +``posix_home`` +^^^^^^^^^^^^^^ + +============== =========================================================== +Path Installation directory +============== =========================================================== +*stdlib* :file:`{home}/lib/python` +*platstdlib* :file:`{home}/lib/python` +*platlib* :file:`{home}/lib/python` +*purelib* :file:`{home}/lib/python` +*include* :file:`{home}/include/python` +*platinclude* :file:`{home}/include/python` +*scripts* :file:`{home}/bin` +*data* :file:`{home}` +============== =========================================================== + + +.. _sysconfig-prefix-scheme: + +Prefix scheme +------------- + +The "prefix scheme" is useful when you wish to use one Python installation to +perform the build/install (i.e., to run the setup script), but install modules +into the third-party module directory of a different Python installation (or +something that looks like a different Python installation). If this sounds a +trifle unusual, it is---that's why the user and home schemes come before. However, +there are at least two known cases where the prefix scheme will be useful. + +First, consider that many Linux distributions put Python in :file:`/usr`, rather +than the more traditional :file:`/usr/local`. This is entirely appropriate, +since in those cases Python is part of "the system" rather than a local add-on. +However, if you are installing Python modules from source, you probably want +them to go in :file:`/usr/local/lib/python2.{X}` rather than +:file:`/usr/lib/python2.{X}`. + +Another possibility is a network filesystem where the name used to write to a +remote directory is different from the name used to read it: for example, the +Python interpreter accessed as :file:`/usr/local/bin/python` might search for +modules in :file:`/usr/local/lib/python2.{X}`, but those modules would have to +be installed to, say, :file:`/mnt/{@server}/export/lib/python2.{X}`. + +``posix_prefix`` +^^^^^^^^^^^^^^^^ + +============== ========================================================== +Path Installation directory +============== ========================================================== +*stdlib* :file:`{prefix}/lib/python{X.Y}` +*platstdlib* :file:`{prefix}/lib/python{X.Y}` +*platlib* :file:`{prefix}/lib/python{X.Y}/site-packages` +*purelib* :file:`{prefix}/lib/python{X.Y}/site-packages` +*include* :file:`{prefix}/include/python{X.Y}` +*platinclude* :file:`{prefix}/include/python{X.Y}` +*scripts* :file:`{prefix}/bin` +*data* :file:`{prefix}` +============== ========================================================== + +``nt`` +^^^^^^ + +============== ========================================================== +Path Installation directory +============== ========================================================== +*stdlib* :file:`{prefix}\\Lib` +*platstdlib* :file:`{prefix}\\Lib` +*platlib* :file:`{prefix}\\Lib\\site-packages` +*purelib* :file:`{prefix}\\Lib\\site-packages` +*include* :file:`{prefix}\\Include` +*platinclude* :file:`{prefix}\\Include` +*scripts* :file:`{prefix}\\Scripts` +*data* :file:`{prefix}` +============== ========================================================== + + +Installation path functions +--------------------------- + +:mod:`sysconfig` provides some functions to determine these installation paths. .. function:: get_scheme_names() diff --git a/Doc/using/cmdline.rst b/Doc/using/cmdline.rst index 921b6a6961c..bade3ca6650 100644 --- a/Doc/using/cmdline.rst +++ b/Doc/using/cmdline.rst @@ -811,7 +811,7 @@ conflict. Defines the :data:`user base directory `, which is used to compute the path of the :data:`user site-packages directory ` - and installation paths for + and :ref:`installation paths ` for ``python -m pip install --user``. .. seealso::