How to get virtualenv to use dist-packages on Ubuntu?

This might be a legitimate use of PYTHONPATH - an environmental variable that virtualenv doesn't touch, which uses the same syntax as the environmental variable PATH, in bash PYTHONPATH=/usr/lib/python2.7/dist-packages:/usr/local/lib/python2.7/dist-packages in a .bashrc or similar. If you followed this path,

1. You don't have to tell your virtual environment about this at all, it won't try to change it.

2. No relinking will be required, and

3. That will still go wherever it would have gone (pip install always uses /usr/local/lib/python2.7/dist-packages/ for my Ubuntu) if you install them outside of your virtual environment. If you install them from within your virtual environment (while it's activated) then of course it'll be put in the virtualenvironment.

I'm just getting my head around virtualenv, but there seems to be an easier way than mentioned so far.

1. Since virtualenv 1.7 --no-site-packages has been the default behavior.Therefore using the --system-site-packages flag to virtualenv is all that is needed to get dist-packages in your path - if you use the tweaked virtualenv shipped by Ubuntu. (This answer and this one give some useful history). I've tested this and it does work.

   $ virtualenv --system-site-packages .

2. I agree with Thomas here - I can't see any action required in virtualenv to see the effect of updates in dist-packages.

3. Having tested that with python setup.py install, it does (again as Thomas said) still go to dist-packages. You could change that by building your own python, but that's a bit extreme.

PYTHONPATH works for me.

vim ~/.bashrc

add this line below:

export PYTHONPATH=$PYTHONPATH:/usr/lib/python2.7/dist-packages:/usr/local/lib/python2.7/dist-packagessource ~/.bashrc