.. highlightlang:: none

.. _using-on-unix:

********************************

 Using Python on Unix platforms

********************************

.. sectionauthor:: Shriphani Palakodety

Getting and installing the latest version of Python

===================================================

On Linux

--------

Python comes preinstalled on most Linux distributions, and is available as a

package on all others.  However there are certain features you might want to use

that are not available on your distro's package.  You can easily compile the

latest version of Python from source.

In the event that Python doesn't come preinstalled and isn't in the repositories as

well, you can easily make packages for your own distro.  Have a look at the

following links:

.. seealso::

   http://www.linux.com/articles/60383

      for Debian users

   http://linuxmafia.com/pub/linux/suse-linux-internals/chapter35.html

      for OpenSuse users

   http://docs.fedoraproject.org/drafts/rpm-guide-en/ch-creating-rpms.html

      for Fedora users

   http://www.slackbook.org/html/package-management-making-packages.html

      for Slackware users

On FreeBSD and OpenBSD

----------------------

* FreeBSD users, to add the package use::

     pkg_add -r python

* OpenBSD users use::

     pkg_add ftp://ftp.openbsd.org/pub/OpenBSD/4.2/packages/<insert your architecture here>/python-<version>.tgz 

  For example i386 users get the 2.5.1 version of Python using::

     pkg_add ftp://ftp.openbsd.org/pub/OpenBSD/4.2/packages/i386/python-2.5.1p2.tgz

On OpenSolaris

--------------

To install the newest Python versions on OpenSolaris, install blastwave

(http://www.blastwave.org/howto.html) and type "pkg_get -i python" at the

prompt.

Building Python

===============

If you want to compile CPython yourself, first thing you should do is get the

`source <http://python.org/download/source/>`_. You can download either the

latest release's source or just grab a fresh `checkout

<http://www.python.org/dev/faq/#how-do-i-get-a-checkout-of-the-repository-read-only-and-read-write>`_.

The build process consists the usual ::

   ./configure

   make

   make install

invocations. Configuration options and caveats for specific Unix platforms are

extensively documented in the :file:`README` file in the root of the Python

source tree.

.. warning::

   ``make install`` can overwrite or masquerade the :file:`python` binary.

   ``make altinstall`` is therefore recommended instead of ``make install``

   since it only installs :file:`{exec_prefix}/bin/python{version}`.

Python-related paths and files

==============================

These are subject to difference depending on local installation conventions;

:envvar:`prefix` (``${prefix}``) and :envvar:`exec_prefix` (``${exec_prefix}``)

are installation-dependent and should be interpreted as for GNU software; they

may be the same.

For example, on most Linux systems, the default for both is :file:`/usr`.

+-----------------------------------------------+------------------------------------------+

| File/directory                                | Meaning                                  |

+===============================================+==========================================+

| :file:`{exec_prefix}/bin/python`              | Recommended location of the interpreter. |

+-----------------------------------------------+------------------------------------------+

| :file:`{prefix}/lib/python{version}`,         | Recommended locations of the directories |

| :file:`{exec_prefix}/lib/python{version}`     | containing the standard modules.         |

+-----------------------------------------------+------------------------------------------+

| :file:`{prefix}/include/python{version}`,     | Recommended locations of the directories |

| :file:`{exec_prefix}/include/python{version}` | containing the include files needed for  |

|                                               | developing Python extensions and         |

|                                               | embedding the interpreter.               |

+-----------------------------------------------+------------------------------------------+

| :file:`~/.pythonrc.py`                        | User-specific initialization file loaded |

|                                               | by the user module; not used by default  |

|                                               | or by most applications.                 |

+-----------------------------------------------+------------------------------------------+

Miscellaneous

=============

To easily use Python scripts on Unix, you need to make them executable,

e.g. with ::

   $ chmod +x script

and put an appropriate Shebang line at the top of the script.  A good choice is

usually ::

   #!/usr/bin/env python

which searches for the Python interpreter in the whole :envvar:`PATH`.  However,

some Unices may not have the :program:`env` command, so you may need to hardcode

``/usr/bin/python`` as the interpreter path.

To use shell commands in your python scripts, look at the :mod:`subprocess` module.

Editors

=======

Vim and Emacs are excellent editors which support Python very well.  For more

information on how to code in python in these editors, look at:

http://www.vim.org/scripts/script.php?script_id=790

http://sourceforge.net/projects/python-mode

Geany is an excellent IDE with support for a lot of languages. For more

information, read: http://geany.uvena.de/

Komodo edit is another extremely good IDE.  It also has support for a lot of

languages. For more information, read:

http://www.activestate.com/store/productdetail.aspx?prdGuid=20f4ed15-6684-4118-a78b-d37ff4058c5f