在Mac OSX上更改python 2.6.6的环境变量

Question

I am trying to add an environmental variable, but by default my computer has installed Python 2.7.

I changed the default using:

defaults write com.apple.versioner.python Version 2.6

I am now trying to change an environmental variable using:

nano ~/.bash_profile

But that is for Python 2.7.

How do I change the environmental variable for 2.6?

Thanks!

Answer 1

As the man page explains, if you want to set an environment variable to make python default to 2.6, it's VERSIONER_PYTHON_VERSION .

So, in your .bash_profile , add this line:

export VERSIONER_PYTHON_VERSION=2.6

However, there's very rarely a good reason to do this. You can always run the version you want explicitly:

$ python2.6
Python 2.6.8 (unknown, Aug 25 2013, 00:04:29)
[GCC 4.2.1 Compatible Apple LLVM 5.0 (clang-500.0.68)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> ^D

… and use a shebang line in your script to do the same:

$ cat <<EOF >test26.py
> #!/usr/bin/env python2.6
> import sys
> print sys.version
> ^D
$ chmod +x test26.py
$ ./test26.py
2.6.8 (unknown, Aug 25 2013, 00:04:29)
[GCC 4.2.1 Compatible Apple LLVM 5.0 (clang-500.0.68)]

More importantly, there's not that much code out there that works with 2.6 but not 2.7. In particular, the reason you want this is because "I am trying to use the Echo Nest Remix package which apparently only works with 2.66 and not 2.7", but the docs say it works with all versions from 2.5 to 2.7, and explicit suggest 2.7 as the best version. The default Mac binary installer here only works in 2.7. If you prefer to install from source, the docs say to use pip or easy_install with whichever Python is the default on your system.

Answer 2

You should use virtualenv to create an isolated Python environment, with whatever version of the interpeter you like. It will make your life a lot easier.

https://pypi.python.org/pypi/virtualenv