[Distutils] How to handle launcher script importability?

[PJ Eby]

On Tue, Aug 20, 2013 at 12:39 PM, Thomas Heller <theller at ctypes.org> wrote:
> Ok, now I understand.  But the zipfile could contain a loader-module
> for each extension which does something like this (this example extracts
> and loads 'bz2.pyd'):
> ...
>
> (py2exe for Python 3, which is work in progress, uses this approach)

Setuptools has also done this since the egg format was developed, but
it has some well-known problems, which unfortunately your example has
worse versions of.  ;-)

Setuptools takes the approach of keeping a per-user cache directory
(so that cleanup isn't required, and so there are no security issues
where somebody can replace a tempfile between you writing it and
importing it), and it uses a unique subdirectory per egg so that
different (say) bz2.pyd files can't conflict with each other.  Even
with these adjustments, Unix users frequently run into issues where
the user a process is running as doesn't have access to a suitable
cache directory, and so it's a common complaint about the use of
zipped eggs.

I thought that at one point you (Thomas) had come up with a way to
load modules into memory from a zipfile without needing to extract
them.  Was that you?  If so, how did that work out?  (ISTR that there
was some sort of licensing issue, too.)