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.. highlightlang:: none
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.. _using-on-windows:
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*************************
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Using Python on Windows
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*************************
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.. sectionauthor:: Robert Lehmann <lehmannro@gmail.com>
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.. sectionauthor:: Steve Dower <steve.dower@microsoft.com>
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This document aims to give an overview of Windows-specific behaviour you should
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know about when using Python on Microsoft Windows.
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Installing Python
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=================
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Unlike most Unix systems and services, Windows does not include a system
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supported installation of Python. To make Python available, the CPython team
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has compiled Windows installers (MSI packages) with every `release
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<https://www.python.org/download/releases/>`_ for many years. These installers
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are primarily intended to add a per-user installation of Python, with the
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core interpreter and library being used by a single user. The installer is also
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able to install for all users of a single machine, and a separate ZIP file is
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available for application-local distributions.
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Installation Steps
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------------------
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Four Python 3.5 installers are available for download - two each for the 32-bit
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and 64-bit versions of the interpreter. The *web installer* is a small initial
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download, and it will automatically download the required components as
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necessary. The *offline installer* includes the components necessary for a
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default installation and only requires an internet connection for optional
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features. See :ref:`install-layout-option` for other ways to avoid downloading
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during installation.
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After starting the installer, one of two options may be selected:
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.. image:: win_installer.png
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If you select "Install Now":
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* You will *not* need to be an administrator (unless a system update for the
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C Runtime Library is required)
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* Python will be installed into your user directory
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* The :ref:`launcher` will *also* be installed into your user directory
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* The standard library, test suite, launcher and pip will be installed
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* If selected, the install directory will be added to your :envvar:`PATH`
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* Shortcuts will only be visible for the current user
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Selecting "Customize installation" will allow you to select the features to
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install, the installation location and other options or post-install actions.
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To install debugging symbols or binaries, you will need to use this option.
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To perform an all-users installation, you should select "Customize
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installation". In this case:
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* You may be required to provide administrative credentials or approval
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* Python will be installed into the Program Files directory
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* The :ref:`launcher` will be installed into the Windows directory
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* Optional features may be selected during installation
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* The standard library will be pre-compiled to bytecode
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* If selected, the install directory will be added to the system :envvar:`PATH`
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* Shortcuts are available for all users
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.. _install-quiet-option:
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Installing Without UI
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---------------------
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All of the options available in the installer UI can also be specified from the
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command line, allowing scripted installers to replicate an installation on many
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machines without user interaction. These options may also be set without
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suppressing the UI in order to change some of the defaults.
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To completely hide the installer UI and install Python silently, pass the
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``/quiet`` (``/q``) option. To skip past the user interaction but still display
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progress and errors, pass the ``/passive`` (``/p``) option. The ``/uninstall``
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option may be passed to immediately begin removing Python - no prompt will be
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displayed.
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All other options are passed as ``name=value``, where the value is usually
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``0`` to disable a feature, ``1`` to enable a feature, or a path. The full list
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of available options is shown below.
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+---------------------------+--------------------------------------+--------------------------+
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| Name | Description | Default |
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+===========================+======================================+==========================+
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| InstallAllUsers | Perform a system-wide installation. | 1 |
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+---------------------------+--------------------------------------+--------------------------+
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| TargetDir | The installation directory | Selected based on |
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| | | InstallAllUsers |
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+---------------------------+--------------------------------------+--------------------------+
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| DefaultAllUsersTargetDir | The default installation directory | :file:`%ProgramFiles%\\\ |
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| | for all-user installs | Python X.Y` or :file:`\ |
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| | | %ProgramFiles(x86)%\\\ |
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| | | Python X.Y` |
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+---------------------------+--------------------------------------+--------------------------+
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| DefaultJustForMeTargetDir | The default install directory for | :file:`%LocalAppData%\\\ |
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| | just-for-me installs | Programs\\PythonXY` or |
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| | | :file:`%LocalAppData%\\\ |
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| | | Programs\\PythonXY-32` |
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+---------------------------+--------------------------------------+--------------------------+
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| DefaultCustomTargetDir | The default custom install directory | (empty) |
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| | displayed in the UI | |
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+---------------------------+--------------------------------------+--------------------------+
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| AssociateFiles | Create file associations if the | 1 |
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| | launcher is also installed. | |
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+---------------------------+--------------------------------------+--------------------------+
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| CompileAll | Compile all ``.py`` files to | 0 |
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| | ``.pyc``. | |
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+---------------------------+--------------------------------------+--------------------------+
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| PrependPath | Add install and Scripts directories | 0 |
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| | tho :envvar:`PATH` and ``.PY`` to | |
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| | :envvar:`PATHEXT` | |
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+---------------------------+--------------------------------------+--------------------------+
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| Shortcuts | Create shortcuts for the interpreter,| 1 |
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| | documentation and IDLE if installed. | |
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+---------------------------+--------------------------------------+--------------------------+
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| Include_doc | Install Python manual | 1 |
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+---------------------------+--------------------------------------+--------------------------+
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| Include_debug | Install debug binaries | 0 |
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+---------------------------+--------------------------------------+--------------------------+
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| Include_dev | Install developer headers and | 1 |
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| | libraries | |
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+---------------------------+--------------------------------------+--------------------------+
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| Include_exe | Install :file:`python.exe` and | 1 |
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| | related files | |
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+---------------------------+--------------------------------------+--------------------------+
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| Include_launcher | Install :ref:`launcher`. | 1 |
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+---------------------------+--------------------------------------+--------------------------+
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| Include_lib | Install standard library and | 1 |
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| | extension modules | |
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+---------------------------+--------------------------------------+--------------------------+
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| Include_pip | Install bundled pip and setuptools | 1 |
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+---------------------------+--------------------------------------+--------------------------+
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| Include_symbols | Install debugging symbols (`*`.pdb) | 0 |
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+---------------------------+--------------------------------------+--------------------------+
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| Include_tcltk | Install Tcl/Tk support and IDLE | 1 |
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+---------------------------+--------------------------------------+--------------------------+
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| Include_test | Install standard library test suite | 1 |
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+---------------------------+--------------------------------------+--------------------------+
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| Include_tools | Install utility scripts | 1 |
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+---------------------------+--------------------------------------+--------------------------+
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| SimpleInstall | Disable most install UI | 0 |
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+---------------------------+--------------------------------------+--------------------------+
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For example, to silently install a default, system-wide Python installation,
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you could use the following command (from an elevated command prompt)::
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python-3.5.0.exe /quiet InstallAllUsers=1 PrependPath=1 Include_test=0
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To allow users to easily install a personal copy of Python without the test
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suite, you could provide a shortcut with the following command::
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python-3.5.0.exe /passive InstallAllUsers=0 Include_launcher=0 Include_test=0 SimpleInstall=1
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(Note that omitting the launcher also omits file associations, and is only
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recommended for per-user installs when there is also a system-wide installation
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that included the launcher.)
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.. _install-layout-option:
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Installing Without Downloading
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------------------------------
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As some features of Python are not included in the initial installer download,
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selecting those features may require an internet connection. To avoid this
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need, all possible components may be downloaded on-demand to create a complete
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*layout* that will no longer require an internet connection regardless of the
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selected features. Note that this download may be bigger than required, but
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where a large number of installations are going to be performed it is very
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useful to have a locally cached copy.
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Execute the following command from Command Prompt to download all possible
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required files. Remember to substitute ``python-3.5.0.exe`` for the actual
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name of your installer, and to create layouts in their own directories to
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avoid collisions between files with the same name.
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::
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python-3.5.0.exe /layout [optional target directory]
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You may also specify the ``/quiet`` option to hide the progress display.
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Other Platforms
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---------------
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With ongoing development of Python, some platforms that used to be supported
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earlier are no longer supported (due to the lack of users or developers).
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Check :pep:`11` for details on all unsupported platforms.
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* `Windows CE <http://pythonce.sourceforge.net/>`_ is still supported.
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* The `Cygwin <http://cygwin.com/>`_ installer offers to install the Python
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interpreter as well (cf. `Cygwin package source
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<ftp://ftp.uni-erlangen.de/pub/pc/gnuwin32/cygwin/mirrors/cygnus/
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release/python>`_, `Maintainer releases
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<http://www.tishler.net/jason/software/python/>`_)
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See `Python for Windows <https://www.python.org/download/windows/>`_
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for detailed information about platforms with pre-compiled installers.
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.. seealso::
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`Python on XP <http://www.richarddooling.com/index.php/2006/03/14/python-on-xp-7-minutes-to-hello-world/>`_
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"7 Minutes to "Hello World!""
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by Richard Dooling, 2006
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`Installing on Windows <http://www.diveintopython.net/installing_python/windows.html>`_
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in "`Dive into Python: Python from novice to pro
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<http://www.diveintopython.net/>`_"
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by Mark Pilgrim, 2004,
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ISBN 1-59059-356-1
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`For Windows users <http://www.swaroopch.com/notes/python/#install_windows>`_
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in "Installing Python"
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in "`A Byte of Python <http://www.swaroopch.com/notes/python/>`_"
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by Swaroop C H, 2003
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Alternative bundles
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===================
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Besides the standard CPython distribution, there are modified packages including
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additional functionality. The following is a list of popular versions and their
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key features:
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`ActivePython <http://www.activestate.com/activepython/>`_
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Installer with multi-platform compatibility, documentation, PyWin32
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`Anaconda <http://www.continuum.io/downloads/>`_
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Popular scientific modules (such as numpy, scipy and pandas) and the
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``conda`` package manager.
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`Canopy <https://www.enthought.com/products/canopy/>`_
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A "comprehensive Python analysis environment" with editors and other
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development tools.
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`WinPython <https://winpython.github.io/>`_
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Windows-specific distribution with prebuilt scientific packages and
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tools for building packages.
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Note that these packages may not include the latest versions of Python or
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other libraries, and are not maintained or supported by the core Python team.
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Configuring Python
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==================
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To run Python conveniently from a command prompt, you might consider changing
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some default environment variables in Windows. While the installer provides an
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option to configure the PATH and PATHEXT variables for you, this is only
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reliable for a single, system-wide installation. If you regularly use multiple
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versions of Python, consider using the :ref:`launcher`.
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.. _setting-envvars:
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Excursus: Setting environment variables
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---------------------------------------
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Windows allows environment variables to be configured permanently at both the
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User level and the System level, or temporarily in a command prompt.
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To temporarily set environment variables, open Command Prompt and use the
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:command:`set` command::
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C:\>set PATH=C:\Program Files\Python 3.5;%PATH%
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C:\>set PYTHONPATH=%PYTHONPATH%;C:\My_python_lib
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C:\>python
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These changes will apply to any further commands executed in that console, and
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will be inherited by any applications started from the console.
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Including the variable name within percent signs will expand to the existing
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value, allowing you to add your new value at either the start or the end.
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Modifying :envvar:`PATH` by adding the directory containing
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:program:`python.exe` to the start is a common way to ensure the correct version
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of Python is launched.
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To permanently modify the default environment variables, click Start and search
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for 'edit environment variables', or open System properties, :guilabel:`Advanced
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system settings` and click the :guilabel:`Environment Variables` button.
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In this dialog, you can add or modify User and System variables. To change
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System variables, you need non-restricted access to your machine
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(i.e. Administrator rights).
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.. note::
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Windows will concatenate User variables *after* System variables, which may
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cause unexpected results when modifying :envvar:`PATH`.
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The :envvar:`PYTHONPATH` variable is used by all versions of Python 2 and
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Python 3, so you should not permanently configure this variable unless it
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only includes code that is compatible with all of your installed Python
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versions.
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.. seealso::
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http://support.microsoft.com/kb/100843
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Environment variables in Windows NT
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http://technet.microsoft.com/en-us/library/cc754250.aspx
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The SET command, for temporarily modifying environment variables
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http://technet.microsoft.com/en-us/library/cc755104.aspx
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The SETX command, for permanently modifying environment variables
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http://support.microsoft.com/kb/310519
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How To Manage Environment Variables in Windows XP
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http://www.chem.gla.ac.uk/~louis/software/faq/q1.html
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Setting Environment variables, Louis J. Farrugia
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.. _windows-path-mod:
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Finding the Python executable
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-----------------------------
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.. versionchanged:: 3.5
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Besides using the automatically created start menu entry for the Python
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interpreter, you might want to start Python in the command prompt. The
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installer for Python 3.5 and later has an option to set that up for you.
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On the first page of the installer, an option labelled "Add Python 3.5 to
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PATH" can be selected to have the installer add the install location into the
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:envvar:`PATH`. The location of the :file:`Scripts\\` folder is also added.
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This allows you to type :command:`python` to run the interpreter, and
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:command:`pip` or . Thus, you can also execute your
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scripts with command line options, see :ref:`using-on-cmdline` documentation.
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If you don't enable this option at install time, you can always re-run the
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installer, select Modify, and enable it. Alternatively, you can manually
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modify the :envvar:`PATH` using the directions in :ref:`setting-envvars`. You
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need to set your :envvar:`PATH` environment variable to include the directory
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of your Python installation, delimited by a semicolon from other entries. An
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example variable could look like this (assuming the first two entries already
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existed)::
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C:\WINDOWS\system32;C:\WINDOWS;C:\Program Files\Python 3.5
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.. _launcher:
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Python Launcher for Windows
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===========================
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.. versionadded:: 3.3
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The Python launcher for Windows is a utility which aids in locating and
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executing of different Python versions. It allows scripts (or the
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command-line) to indicate a preference for a specific Python version, and
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will locate and execute that version.
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Unlike the :envvar:`PATH` variable, the launcher will correctly select the most
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appropriate version of Python. It will prefer per-user installations over
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system-wide ones, and orders by language version rather than using the most
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recently installed version.
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Getting started
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---------------
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From the command-line
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^^^^^^^^^^^^^^^^^^^^^
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System-wide installations of Python 3.3 and later will put the launcher on your
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:envvar:`PATH`. The launcher is compatible with all available versions of
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Python, so it does not matter which version is installed. To check that the
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launcher is available, execute the following command in Command Prompt:
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::
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py
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You should find that the latest version of Python 2.x you have installed is
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started - it can be exited as normal, and any additional command-line
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arguments specified will be sent directly to Python.
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If you have multiple versions of Python 2.x installed (e.g., 2.6 and 2.7) you
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will have noticed that Python 2.7 was started - to launch Python 2.6, try the
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command:
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::
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py -2.6
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If you have a Python 3.x installed, try the command:
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::
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py -3
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You should find the latest version of Python 3.x starts.
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If you see the following error, you do not have the launcher installed:
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::
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'py' is not recognized as an internal or external command,
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operable program or batch file.
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Per-user installations of Python do not add the launcher to :envvar:`PATH`
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unless the option was selected on installation.
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Virtual environments
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^^^^^^^^^^^^^^^^^^^^
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.. versionadded:: 3.5
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If the launcher is run with no explicit Python version specification, and a
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virtual environment (created with the standard library :mod:`venv` module or
|
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the external ``virtualenv`` tool) active, the launcher will run the virtual
|
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environment's interpreter rather than the global one. To run the global
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interpreter, either deactivate the virtual environment, or explicitly specify
|
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the global Python version.
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From a script
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^^^^^^^^^^^^^
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Let's create a test Python script - create a file called ``hello.py`` with the
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following contents
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::
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#! python
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import sys
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sys.stdout.write("hello from Python %s\n" % (sys.version,))
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From the directory in which hello.py lives, execute the command:
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::
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py hello.py
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You should notice the version number of your latest Python 2.x installation
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is printed. Now try changing the first line to be:
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::
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#! python3
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Re-executing the command should now print the latest Python 3.x information.
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As with the above command-line examples, you can specify a more explicit
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version qualifier. Assuming you have Python 2.6 installed, try changing the
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first line to ``#! python2.6`` and you should find the 2.6 version
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information printed.
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From file associations
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^^^^^^^^^^^^^^^^^^^^^^
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The launcher should have been associated with Python files (i.e. ``.py``,
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``.pyw``, ``.pyc`` files) when it was installed. This means that
|
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when you double-click on one of these files from Windows explorer the launcher
|
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will be used, and therefore you can use the same facilities described above to
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have the script specify the version which should be used.
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The key benefit of this is that a single launcher can support multiple Python
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versions at the same time depending on the contents of the first line.
|
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Shebang Lines
|
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-------------
|
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If the first line of a script file starts with ``#!``, it is known as a
|
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"shebang" line. Linux and other Unix like operating systems have native
|
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support for such lines and are commonly used on such systems to indicate how
|
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a script should be executed. This launcher allows the same facilities to be
|
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using with Python scripts on Windows and the examples above demonstrate their
|
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use.
|
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To allow shebang lines in Python scripts to be portable between Unix and
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Windows, this launcher supports a number of 'virtual' commands to specify
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which interpreter to use. The supported virtual commands are:
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* ``/usr/bin/env python``
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* ``/usr/bin/python``
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* ``/usr/local/bin/python``
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* ``python``
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For example, if the first line of your script starts with
|
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::
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#! /usr/bin/python
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The default Python will be located and used. As many Python scripts written
|
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to work on Unix will already have this line, you should find these scripts can
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be used by the launcher without modification. If you are writing a new script
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on Windows which you hope will be useful on Unix, you should use one of the
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shebang lines starting with ``/usr``.
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Any of the above virtual commands can be suffixed with an explicit version
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(either just the major version, or the major and minor version) - for example
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``/usr/bin/python2.7`` - which will cause that specific version to be located
|
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and used.
|
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The ``/usr/bin/env`` form of shebang line has one further special property.
|
|
Before looking for installed Python interpreters, this form will search the
|
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executable :envvar:`PATH` for a Python executable. This corresponds to the
|
|
behaviour of the Unix ``env`` program, which performs a :envvar:`PATH` search.
|
|
|
|
Arguments in shebang lines
|
|
--------------------------
|
|
|
|
The shebang lines can also specify additional options to be passed to the
|
|
Python interpreter. For example, if you have a shebang line:
|
|
|
|
::
|
|
|
|
#! /usr/bin/python -v
|
|
|
|
Then Python will be started with the ``-v`` option
|
|
|
|
Customization
|
|
-------------
|
|
|
|
Customization via INI files
|
|
^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
Two .ini files will be searched by the launcher - ``py.ini`` in the current
|
|
user's "application data" directory (i.e. the directory returned by calling the
|
|
Windows function SHGetFolderPath with CSIDL_LOCAL_APPDATA) and ``py.ini`` in the
|
|
same directory as the launcher. The same .ini files are used for both the
|
|
'console' version of the launcher (i.e. py.exe) and for the 'windows' version
|
|
(i.e. pyw.exe)
|
|
|
|
Customization specified in the "application directory" will have precedence over
|
|
the one next to the executable, so a user, who may not have write access to the
|
|
.ini file next to the launcher, can override commands in that global .ini file)
|
|
|
|
Customizing default Python versions
|
|
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
In some cases, a version qualifier can be included in a command to dictate
|
|
which version of Python will be used by the command. A version qualifier
|
|
starts with a major version number and can optionally be followed by a period
|
|
('.') and a minor version specifier. If the minor qualifier is specified, it
|
|
may optionally be followed by "-32" to indicate the 32-bit implementation of
|
|
that version be used.
|
|
|
|
For example, a shebang line of ``#!python`` has no version qualifier, while
|
|
``#!python3`` has a version qualifier which specifies only a major version.
|
|
|
|
If no version qualifiers are found in a command, the environment variable
|
|
``PY_PYTHON`` can be set to specify the default version qualifier - the default
|
|
value is "2". Note this value could specify just a major version (e.g. "2") or
|
|
a major.minor qualifier (e.g. "2.6"), or even major.minor-32.
|
|
|
|
If no minor version qualifiers are found, the environment variable
|
|
``PY_PYTHON{major}`` (where ``{major}`` is the current major version qualifier
|
|
as determined above) can be set to specify the full version. If no such option
|
|
is found, the launcher will enumerate the installed Python versions and use
|
|
the latest minor release found for the major version, which is likely,
|
|
although not guaranteed, to be the most recently installed version in that
|
|
family.
|
|
|
|
On 64-bit Windows with both 32-bit and 64-bit implementations of the same
|
|
(major.minor) Python version installed, the 64-bit version will always be
|
|
preferred. This will be true for both 32-bit and 64-bit implementations of the
|
|
launcher - a 32-bit launcher will prefer to execute a 64-bit Python installation
|
|
of the specified version if available. This is so the behavior of the launcher
|
|
can be predicted knowing only what versions are installed on the PC and
|
|
without regard to the order in which they were installed (i.e., without knowing
|
|
whether a 32 or 64-bit version of Python and corresponding launcher was
|
|
installed last). As noted above, an optional "-32" suffix can be used on a
|
|
version specifier to change this behaviour.
|
|
|
|
Examples:
|
|
|
|
* If no relevant options are set, the commands ``python`` and
|
|
``python2`` will use the latest Python 2.x version installed and
|
|
the command ``python3`` will use the latest Python 3.x installed.
|
|
|
|
* The commands ``python3.1`` and ``python2.7`` will not consult any
|
|
options at all as the versions are fully specified.
|
|
|
|
* If ``PY_PYTHON=3``, the commands ``python`` and ``python3`` will both use
|
|
the latest installed Python 3 version.
|
|
|
|
* If ``PY_PYTHON=3.1-32``, the command ``python`` will use the 32-bit
|
|
implementation of 3.1 whereas the command ``python3`` will use the latest
|
|
installed Python (PY_PYTHON was not considered at all as a major
|
|
version was specified.)
|
|
|
|
* If ``PY_PYTHON=3`` and ``PY_PYTHON3=3.1``, the commands
|
|
``python`` and ``python3`` will both use specifically 3.1
|
|
|
|
In addition to environment variables, the same settings can be configured
|
|
in the .INI file used by the launcher. The section in the INI file is
|
|
called ``[defaults]`` and the key name will be the same as the
|
|
environment variables without the leading ``PY_`` prefix (and note that
|
|
the key names in the INI file are case insensitive.) The contents of
|
|
an environment variable will override things specified in the INI file.
|
|
|
|
For example:
|
|
|
|
* Setting ``PY_PYTHON=3.1`` is equivalent to the INI file containing:
|
|
|
|
::
|
|
|
|
[defaults]
|
|
python=3.1
|
|
|
|
* Setting ``PY_PYTHON=3`` and ``PY_PYTHON3=3.1`` is equivalent to the INI file
|
|
containing:
|
|
|
|
::
|
|
|
|
[defaults]
|
|
python=3
|
|
python3=3.1
|
|
|
|
Diagnostics
|
|
-----------
|
|
|
|
If an environment variable ``PYLAUNCH_DEBUG`` is set (to any value), the
|
|
launcher will print diagnostic information to stderr (i.e. to the console).
|
|
While this information manages to be simultaneously verbose *and* terse, it
|
|
should allow you to see what versions of Python were located, why a
|
|
particular version was chosen and the exact command-line used to execute the
|
|
target Python.
|
|
|
|
|
|
|
|
Finding modules
|
|
===============
|
|
|
|
Python usually stores its library (and thereby your site-packages folder) in the
|
|
installation directory. So, if you had installed Python to
|
|
:file:`C:\\Python\\`, the default library would reside in
|
|
:file:`C:\\Python\\Lib\\` and third-party modules should be stored in
|
|
:file:`C:\\Python\\Lib\\site-packages\\`.
|
|
|
|
This is how :data:`sys.path` is populated on Windows:
|
|
|
|
* An empty entry is added at the start, which corresponds to the current
|
|
directory.
|
|
|
|
* If the environment variable :envvar:`PYTHONPATH` exists, as described in
|
|
:ref:`using-on-envvars`, its entries are added next. Note that on Windows,
|
|
paths in this variable must be separated by semicolons, to distinguish them
|
|
from the colon used in drive identifiers (``C:\`` etc.).
|
|
|
|
* Additional "application paths" can be added in the registry as subkeys of
|
|
:samp:`\\SOFTWARE\\Python\\PythonCore\\{version}\\PythonPath` under both the
|
|
``HKEY_CURRENT_USER`` and ``HKEY_LOCAL_MACHINE`` hives. Subkeys which have
|
|
semicolon-delimited path strings as their default value will cause each path
|
|
to be added to :data:`sys.path`. (Note that all known installers only use
|
|
HKLM, so HKCU is typically empty.)
|
|
|
|
* If the environment variable :envvar:`PYTHONHOME` is set, it is assumed as
|
|
"Python Home". Otherwise, the path of the main Python executable is used to
|
|
locate a "landmark file" (``Lib\os.py``) to deduce the "Python Home". If a
|
|
Python home is found, the relevant sub-directories added to :data:`sys.path`
|
|
(``Lib``, ``plat-win``, etc) are based on that folder. Otherwise, the core
|
|
Python path is constructed from the PythonPath stored in the registry.
|
|
|
|
* If the Python Home cannot be located, no :envvar:`PYTHONPATH` is specified in
|
|
the environment, and no registry entries can be found, a default path with
|
|
relative entries is used (e.g. ``.\Lib;.\plat-win``, etc).
|
|
|
|
If a ``pyvenv.cfg`` file is found alongside the main executable or in the
|
|
directory one level above the executable, the following variations apply:
|
|
|
|
* If ``home`` is an absolute path and :envvar:`PYTHONHOME` is not set, this
|
|
path is used instead of the path to the main executable when deducing the
|
|
home location.
|
|
|
|
* If ``applocal`` is set to true, the ``home`` property or the main executable
|
|
is always used as the home path, and all environment variables or registry
|
|
values affecting the path are ignored. The landmark file is not checked.
|
|
|
|
The end result of all this is:
|
|
|
|
* When running :file:`python.exe`, or any other .exe in the main Python
|
|
directory (either an installed version, or directly from the PCbuild
|
|
directory), the core path is deduced, and the core paths in the registry are
|
|
ignored. Other "application paths" in the registry are always read.
|
|
|
|
* When Python is hosted in another .exe (different directory, embedded via COM,
|
|
etc), the "Python Home" will not be deduced, so the core path from the
|
|
registry is used. Other "application paths" in the registry are always read.
|
|
|
|
* If Python can't find its home and there are no registry value (frozen .exe,
|
|
some very strange installation setup) you get a path with some default, but
|
|
relative, paths.
|
|
|
|
For those who want to bundle Python into their application or distribution, the
|
|
following advice will prevent conflicts with other installations:
|
|
|
|
* Include a ``pyvenv.cfg`` file alongside your executable containing
|
|
``applocal = true``. This will ensure that your own directory will be used to
|
|
resolve paths even if you have included the standard library in a ZIP file.
|
|
|
|
* If you are loading :file:`python3.dll` or :file:`python35.dll` in your own
|
|
executable, explicitly call :c:func:`Py_SetPath` or (at least)
|
|
:c:func:`Py_SetProgramName` before :c:func:`Py_Initialize`.
|
|
|
|
* Clear and/or overwrite :envvar:`PYTHONPATH` and set :envvar:`PYTHONHOME`
|
|
before launching :file:`python.exe` from your application.
|
|
|
|
* If you cannot use the previous suggestions (for example, you are a
|
|
distribution that allows people to run :file:`python.exe` directly), ensure
|
|
that the landmark file (:file:`Lib\\os.py`) exists in your install directory.
|
|
(Note that it will not be detected inside a ZIP file.)
|
|
|
|
These will ensure that the files in a system-wide installation will not take
|
|
precedence over the copy of the standard library bundled with your application.
|
|
Otherwise, your users may experience problems using your application.
|
|
|
|
Additional modules
|
|
==================
|
|
|
|
Even though Python aims to be portable among all platforms, there are features
|
|
that are unique to Windows. A couple of modules, both in the standard library
|
|
and external, and snippets exist to use these features.
|
|
|
|
The Windows-specific standard modules are documented in
|
|
:ref:`mswin-specific-services`.
|
|
|
|
PyWin32
|
|
-------
|
|
|
|
The `PyWin32 <http://python.net/crew/mhammond/win32/>`_ module by Mark Hammond
|
|
is a collection of modules for advanced Windows-specific support. This includes
|
|
utilities for:
|
|
|
|
* `Component Object Model <http://www.microsoft.com/com/>`_ (COM)
|
|
* Win32 API calls
|
|
* Registry
|
|
* Event log
|
|
* `Microsoft Foundation Classes <http://msdn.microsoft.com/en-us/library/fe1cf721%28VS.80%29.aspx>`_ (MFC)
|
|
user interfaces
|
|
|
|
`PythonWin <http://web.archive.org/web/20060524042422/
|
|
https://www.python.org/windows/pythonwin/>`_ is a sample MFC application
|
|
shipped with PyWin32. It is an embeddable IDE with a built-in debugger.
|
|
|
|
.. seealso::
|
|
|
|
`Win32 How Do I...? <http://timgolden.me.uk/python/win32_how_do_i.html>`_
|
|
by Tim Golden
|
|
|
|
`Python and COM <http://www.boddie.org.uk/python/COM.html>`_
|
|
by David and Paul Boddie
|
|
|
|
|
|
cx_Freeze
|
|
---------
|
|
|
|
`cx_Freeze <http://cx-freeze.sourceforge.net/>`_ is a :mod:`distutils`
|
|
extension (see :ref:`extending-distutils`) which wraps Python scripts into
|
|
executable Windows programs (:file:`{*}.exe` files). When you have done this,
|
|
you can distribute your application without requiring your users to install
|
|
Python.
|
|
|
|
|
|
WConio
|
|
------
|
|
|
|
Since Python's advanced terminal handling layer, :mod:`curses`, is restricted to
|
|
Unix-like systems, there is a library exclusive to Windows as well: Windows
|
|
Console I/O for Python.
|
|
|
|
`WConio <http://newcenturycomputers.net/projects/wconio.html>`_ is a wrapper for
|
|
Turbo-C's :file:`CONIO.H`, used to create text user interfaces.
|
|
|
|
|
|
|
|
Compiling Python on Windows
|
|
===========================
|
|
|
|
If you want to compile CPython yourself, first thing you should do is get the
|
|
`source <https://www.python.org/download/source/>`_. You can download either the
|
|
latest release's source or just grab a fresh `checkout
|
|
<https://docs.python.org/devguide/setup.html#getting-the-source-code>`_.
|
|
|
|
The source tree contains a build solution and project files for Microsoft
|
|
Visual Studio 2015, which is the compiler used to build the official Python
|
|
releases. These files are in the :file:`PCbuild` directory.
|
|
|
|
Check :file:`PCbuild/readme.txt` for general information on the build process.
|
|
|
|
|
|
For extension modules, consult :ref:`building-on-windows`.
|
|
|
|
.. seealso::
|
|
|
|
`Python + Windows + distutils + SWIG + gcc MinGW <http://sebsauvage.net/python/mingw.html>`_
|
|
or "Creating Python extensions in C/C++ with SWIG and compiling them with
|
|
MinGW gcc under Windows" or "Installing Python extension with distutils
|
|
and without Microsoft Visual C++" by Sébastien Sauvage, 2003
|
|
|
|
`MingW -- Python extensions <http://oldwiki.mingw.org/index.php/Python%20extensions>`_
|
|
by Trent Apted et al, 2007
|
|
|
|
|
|
Other resources
|
|
===============
|
|
|
|
.. seealso::
|
|
|
|
`Python Programming On Win32 <http://shop.oreilly.com/product/9781565926219.do>`_
|
|
"Help for Windows Programmers"
|
|
by Mark Hammond and Andy Robinson, O'Reilly Media, 2000,
|
|
ISBN 1-56592-621-8
|
|
|
|
`A Python for Windows Tutorial <http://www.imladris.com/Scripts/PythonForWindows.html>`_
|
|
by Amanda Birmingham, 2004
|
|
|
|
:pep:`397` - Python launcher for Windows
|
|
The proposal for the launcher to be included in the Python distribution.
|