/Doc/using/mac.rst

  1
  2.. _using-on-mac:
  3
  4***************************
  5Using Python on a Macintosh
  6***************************
  7
  8:Author: Bob Savage <bobsavage@mac.com>
  9
 10
 11Python on a Macintosh running Mac OS X is in principle very similar to Python on
 12any other Unix platform, but there are a number of additional features such as
 13the IDE and the Package Manager that are worth pointing out.
 14
 15The Mac-specific modules are documented in :ref:`mac-specific-services`.
 16
 17Python on Mac OS 9 or earlier can be quite different from Python on Unix or
 18Windows, but is beyond the scope of this manual, as that platform is no longer
 19supported, starting with Python 2.4. See http://www.cwi.nl/~jack/macpython for
 20installers for the latest 2.3 release for Mac OS 9 and related documentation.
 21
 22
 23.. _getting-osx:
 24
 25Getting and Installing MacPython
 26================================
 27
 28Mac OS X 10.5 comes with Python 2.5.1 pre-installed by Apple.  If you wish, you
 29are invited to install the most recent version of Python from the Python website
 30(http://www.python.org).  A current "universal binary" build of Python, which
 31runs natively on the Mac's new Intel and legacy PPC CPU's, is available there.
 32
 33What you get after installing is a number of things:
 34
 35* A :file:`MacPython 2.5` folder in your :file:`Applications` folder. In here
 36  you find IDLE, the development environment that is a standard part of official
 37  Python distributions; PythonLauncher, which handles double-clicking Python
 38  scripts from the Finder; and the "Build Applet" tool, which allows you to
 39  package Python scripts as standalone applications on your system.
 40
 41* A framework :file:`/Library/Frameworks/Python.framework`, which includes the
 42  Python executable and libraries. The installer adds this location to your shell
 43  path. To uninstall MacPython, you can simply remove these three things. A
 44  symlink to the Python executable is placed in /usr/local/bin/.
 45
 46The Apple-provided build of Python is installed in
 47:file:`/System/Library/Frameworks/Python.framework` and :file:`/usr/bin/python`,
 48respectively. You should never modify or delete these, as they are
 49Apple-controlled and are used by Apple- or third-party software.  Remember that
 50if you choose to install a newer Python version from python.org, you will have
 51two different but functional Python installations on your computer, so it will
 52be important that your paths and usages are consistent with what you want to do.
 53
 54IDLE includes a help menu that allows you to access Python documentation. If you
 55are completely new to Python you should start reading the tutorial introduction
 56in that document.
 57
 58If you are familiar with Python on other Unix platforms you should read the
 59section on running Python scripts from the Unix shell.
 60
 61
 62How to run a Python script
 63--------------------------
 64
 65Your best way to get started with Python on Mac OS X is through the IDLE
 66integrated development environment, see section :ref:`ide` and use the Help menu
 67when the IDE is running.
 68
 69If you want to run Python scripts from the Terminal window command line or from
 70the Finder you first need an editor to create your script. Mac OS X comes with a
 71number of standard Unix command line editors, :program:`vim` and
 72:program:`emacs` among them. If you want a more Mac-like editor,
 73:program:`BBEdit` or :program:`TextWrangler` from Bare Bones Software (see
 74http://www.barebones.com/products/bbedit/index.shtml) are good choices, as is
 75:program:`TextMate` (see http://macromates.com/). Other editors include
 76:program:`Gvim` (http://macvim.org) and :program:`Aquamacs`
 77(http://aquamacs.org).
 78
 79To run your script from the Terminal window you must make sure that
 80:file:`/usr/local/bin` is in your shell search path.
 81
 82To run your script from the Finder you have two options:
 83
 84* Drag it to :program:`PythonLauncher`
 85
 86* Select :program:`PythonLauncher` as the default application to open your
 87  script (or any .py script) through the finder Info window and double-click it.
 88  :program:`PythonLauncher` has various preferences to control how your script is
 89  launched. Option-dragging allows you to change these for one invocation, or use
 90  its Preferences menu to change things globally.
 91
 92
 93.. _osx-gui-scripts:
 94
 95Running scripts with a GUI
 96--------------------------
 97
 98With older versions of Python, there is one Mac OS X quirk that you need to be
 99aware of: programs that talk to the Aqua window manager (in other words,
100anything that has a GUI) need to be run in a special way. Use :program:`pythonw`
101instead of :program:`python` to start such scripts.
102
103With Python 2.5, you can use either :program:`python` or :program:`pythonw`.
104
105
106Configuration
107-------------
108
109Python on OS X honors all standard Unix environment variables such as
110:envvar:`PYTHONPATH`, but setting these variables for programs started from the
111Finder is non-standard as the Finder does not read your :file:`.profile` or
112:file:`.cshrc` at startup. You need to create a file :file:`~
113/.MacOSX/environment.plist`. See Apple's Technical Document QA1067 for details.
114
115For more information on installation Python packages in MacPython, see section
116:ref:`mac-package-manager`.
117
118
119.. _ide:
120
121The IDE
122=======
123
124MacPython ships with the standard IDLE development environment. A good
125introduction to using IDLE can be found at http://hkn.eecs.berkeley.edu/
126dyoo/python/idle_intro/index.html.
127
128
129.. _mac-package-manager:
130
131Installing Additional Python Packages
132=====================================
133
134There are several methods to install additional Python packages:
135
136* http://pythonmac.org/packages/ contains selected compiled packages for Python
137  2.5, 2.4, and 2.3.
138
139* Packages can be installed via the standard Python distutils mode (``python
140  setup.py install``).
141
142* Many packages can also be installed via the :program:`setuptools` extension.
143
144
145GUI Programming on the Mac
146==========================
147
148There are several options for building GUI applications on the Mac with Python.
149
150*PyObjC* is a Python binding to Apple's Objective-C/Cocoa framework, which is
151the foundation of most modern Mac development. Information on PyObjC is
152available from http://pyobjc.sourceforge.net.
153
154The standard Python GUI toolkit is :mod:`Tkinter`, based on the cross-platform
155Tk toolkit (http://www.tcl.tk). An Aqua-native version of Tk is bundled with OS
156X by Apple, and the latest version can be downloaded and installed from
157http://www.activestate.com; it can also be built from source.
158
159*wxPython* is another popular cross-platform GUI toolkit that runs natively on
160Mac OS X. Packages and documentation are available from http://www.wxpython.org.
161
162*PyQt* is another popular cross-platform GUI toolkit that runs natively on Mac
163OS X. More information can be found at
164http://www.riverbankcomputing.co.uk/software/pyqt/intro.
165
166
167Distributing Python Applications on the Mac
168===========================================
169
170The "Build Applet" tool that is placed in the MacPython 2.5 folder is fine for
171packaging small Python scripts on your own machine to run as a standard Mac
172application. This tool, however, is not robust enough to distribute Python
173applications to other users.
174
175The standard tool for deploying standalone Python applications on the Mac is
176:program:`py2app`. More information on installing and using py2app can be found
177at http://undefined.org/python/#py2app.
178
179
180Application Scripting
181=====================
182
183Python can also be used to script other Mac applications via Apple's Open
184Scripting Architecture (OSA); see http://appscript.sourceforge.net. Appscript is
185a high-level, user-friendly Apple event bridge that allows you to control
186scriptable Mac OS X applications using ordinary Python scripts. Appscript makes
187Python a serious alternative to Apple's own *AppleScript* language for
188automating your Mac. A related package, *PyOSA*, is an OSA language component
189for the Python scripting language, allowing Python code to be executed by any
190OSA-enabled application (Script Editor, Mail, iTunes, etc.). PyOSA makes Python
191a full peer to AppleScript.
192
193
194Other Resources
195===============
196
197The MacPython mailing list is an excellent support resource for Python users and
198developers on the Mac:
199
200http://www.python.org/community/sigs/current/pythonmac-sig/
201
202Another useful resource is the MacPython wiki:
203
204http://wiki.python.org/moin/MacPython
205