In bash, “which” gives an incorrect path - Python versions

Question

Can anyone explain how python 2.6 could be getting run by default on my machine? It looks like python points to 2.7, so it seems like which isn\'t

Answer 1

Bash uses an internal hash table to optimize $PATH lookups. When you install a new program with the same name as an existing program (python in this case) earlier in your $PATH, Bash doesn't know about it and continues to use the old one. The which executable does a full $PATH search and prints out the intended result.

To fix this, run the command hash -d python. This will delete python from Bash's hash table and force it to do a full $PATH search the next time you invoke it. Alternatively, you can also run hash -r to clear out the hash table entirely.

The type builtin will tell you how a given command will be interpreted. If it says that a command is hashed, that means that Bash is going to skip the $PATH search for the executable.

Answer 2

I just checked my .bash_profile, and it contained the following:

# Setting PATH for MacPython 2.6
# The orginal version is saved in .bash_profile.pysave
PATH="/Library/Frameworks/Python.framework/Versions/2.6/bin:/usr/local/git/bin:${PATH}"
export PATH

Commenting this out has fixed my problem.

If someone can tell me why which and type still gave incorrect answers, I'd be very grateful, and will give them a check-mark!

Thanks for all your guidance!