In bash, "which" gives an incorrect path - Python versions
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 开发者_Go百科which
isn't giving me correct information.
~> python --version
Python 2.6.5
~> which python
/opt/local/bin/python
~> /opt/local/bin/python --version
Python 2.7.2
~> ls -l /opt/local/bin/python
lrwxr-xr-x 1 root admin 24 12 Oct 16:02 /opt/local/bin/python -> /opt/local/bin/python2.7
When I generate an error, I see what's really getting run. Why could this be?
~> python -error-making-argument
Unknown option: -e
usage: /Library/Frameworks/Python.framework/Versions/2.6/Resources/Python.app/Contents/MacOS/Python [option] ... [-c cmd | -m mod | file | -] [arg] ...
Try `python -h' for more information.
And how can I correct it?
From suggestions in comments:
~> alias
alias cp='cp -i'
alias gcc='gcc -Wall'
~> type python
python is /opt/local/bin/python
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 $PATH
search for the executable.
I just checked my .bash_profile
, and it contained the following:
# Setting PATH for MacPython 2.6
# The orginal version is saved in .bash_profile.pysave
PATH="/Library/Frameworks/Python.framework/Versions/2.6/bin:/usr/local/git/bin:${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!
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