A couple virtual env questions

[Skip Montanaro]

I built and installed Python from Mercurial tip (head, whatever), so I have
a Python 3.6.0a0 available. I created a virtualenv using that.

Q1: Suppose I install something like matplotlib into that virtualenv which
itself contains extension modules. Those will depend on the include files
and shared libraries from Python itself. If I update my Python install, how
do I detect that matplotlib needs to be rebuilt? I didn't see any obvious
pip command to help with this.

Q2: My normal environment is a work-specific Python 2.7 install. For that,
I have PYTHONPATH set most/all of the time. I tried unsetting it when I
created the virtual environment, but after activating it, PYTHONPATH is
still set. Is there an automatic way to keep my global environment
(PYTHONPATH, PYTHONSTARTUP, etc) from polluting my virtual env?

Thx,

Skip
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20150715/17a05b8e/attachment.html>