In article <805e7543-96ed-474f-8059-123b4085c...@mac.com>, Tom Bridgman <cygnu...@mac.com> wrote: > Is there a reliable way to install python 3 on a Mac without damaging > the resident installation? Are there 10.4 vs 10.5 issues?
It's easy to install multiple versions and there should be no danger of damage. The python.org 3.0.1 should install on any 10.4 or 10.5 system (actually 10.3.x as well, though I don't think that has been tested). It will install the Python framework at /Library/Frameworks/Versions/3.0 and it will install the folder /Applications/Python 3.0. In the latter folder will be IDLE, Update Shell Profile, and some Extras. By default, the installer will *not* modify your shell profile to add python3.0 to your shell $PATH. You can access 3.0 by launching the 3.0 IDLE. If you want to use python3.0 from a shell without making it your default python, you can type in the full path. /Library/Frameworks/Python.framework/Versions/3.0/bin/python3.0 Or you can create a shell alias to that path (see below). If you do want to make python3.0 your default python, either edit your shell profile to add the path of the framework bin directory to the front of your PATH or click on the "Update Shell Profile" command to do it for you. The python.org 2.x installers work exactly the same way, installing into /Library/Frameworks/Versions/2.x and /Applications/Python 2.6 (or /Applications/MacPython 2.x for 2.5 and earlier) All versions can co-exist with each other and with the Apple-supplied python which lives in /System/Library/Versions/Python.framework/2.5 for 10.5 and 2.3 for 10.4. The Apple-supplied python is also linked to from /usr/bin/python. (Like everything else under /System, the python files there are managed by Apple and should remain undisturbed.) So, depending on which pythons you have installed, you could set up shell aliases in your shell profile, like: alias python3.0=\ "/Library/Frameworks/Python.framework/Versions/3.0/bin/python3.0" alias python2.6=\ "/Library/Frameworks/Python.framework/Versions/2.6/bin/python2.6" alias python2.5=\ "/Library/Frameworks/Python.framework/Versions/2.5/bin/python2.5" alias applepython2.5=\ "/System/Library/Frameworks/Python.framework/Versions/2.5/bin/python2.5" alias macportspython2.5=\ "/opt/local/bin/python2.5" alias finkpython2.5=\ "/sw/bin/python2.5" ... By default, each instance of python has its own site-packages directory, so when installing packages, you need to pay attention to which python you are running. If you are installing by hand, make sure you install to the right python by doing something like: python3.0 setup.py ... If you want to use easy_install, you'll probably need to install setuptools in each python version. For the python.org 2.x versions, download from and follow the instructions here: <http://pypi.python.org/pypi/setuptools> The 10.5 Apple python comes with setuptools pre-installed linked at /usr/bin/easy_install. MacPorts and Fink have setuptools packages. You may want to create aliases to the various easy_installs. There isn't a supported 3.0 version of easy_install yet but people are working on it. It would be nice to have a more intuitive way to manage the nest of pythons. There will be likely be some discussion and perhaps some work on that at the upcoming Pycon. I'm sure I'm missing some details here but I hope that gives you enough to feel comfortable exploring 3.0. -- Ned Deily, n...@acm.org _______________________________________________ Pythonmac-SIG maillist - Pythonmac-SIG@python.org http://mail.python.org/mailman/listinfo/pythonmac-sig
