title: osx install packages inside virtualenv
body: <p>I tried to start virtualenv WITHOUT sudo but unfortunately it cannot find (Permission denied) /lib/python2.7/site-packages/easy_install.py. So I did:</p>
  
  <pre><code>sudo virtualenv name_env
  </code></pre>
  
  <p>The problem is that now pip is the global version (not inside pip):
  which pip:
  /usr/local/bin/pip
  So I cannot install any package inside the environment.
  If I start virtualenv without sudo:</p>
  
  <pre><code>virtualenv name_env
  </code></pre>
  
  <p>OSError: Command /Users/andrea/package_lambda/bin/python2.7 -c "import sys, pip; sys...d\"] + sys.argv[1:]))" setuptools pip wheel failed with error code 2
  Any suggestion?</p>