Vinay Sajip added the comment:
As an extra data point, note the behaviour on Windows:
C:\Users\Vinay> \python34\python -m venv "\Temp\aaa bbb"
C:\Users\Vinay> "\Temp\aaa bbb\Scripts\pip" --version
pip 6.0.8 from C:\Temp\aaa bbb\lib\site-packages (python 3.4)
C:\Users\Vinay> pyzzer -i "\Temp\aaa bbb\Scripts\pip.exe"
There is a launcher.
Shebang: #!"C:\Temp\aaa bbb\Scripts\python.exe"
Archive contents:
__main__.py
C:\Users\Vinay> "\Temp\aaa bbb\Scripts\python" -m pip install -U pip
You are using pip version 6.0.8, however version 9.0.1 is available.
You should consider upgrading via the 'pip install --upgrade pip' command.
Collecting pip from https://pypi.python.org/packages/b6/ac/7015eb97dc749283ffdec1c3a88ddb8ae03b8fad0f0e611408f1
96358da3/pip-9.0.1-py2.py3-none-any.whl#md5=297dbd16ef53bcef0447d245815f5144
Using cached pip-9.0.1-py2.py3-none-any.whl
Installing collected packages: pip
Found existing installation: pip 6.0.8
Uninstalling pip-6.0.8:
Successfully uninstalled pip-6.0.8
Successfully installed pip-9.0.1
C:\Users\Vinay> "\Temp\aaa bbb\Scripts\pip" --version
pip 9.0.1 from C:\Temp\aaa bbb\lib\site-packages (python 3.4)
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Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue28446>
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