On Wed, Mar 18, 2015 at 9:48 AM Barry Warsaw <barry@python.org> wrote:
On Mar 18, 2015, at 05:31 PM, Victor Stinner wrote:
Does it work to pass command line options to Python in the shebang?
Yes, but only one "word", thus -Es or -I.
We've often mused about whether it makes sense to have two Pythons on the system. One for system scripts and another for users. System Python ('/usr/bin/spython' perhaps) would be locked down and only extensible by system packages. On Debuntu that might mean no /usr/local on sys.path. It would also have a much more limited set of installed packages, i.e. only those needed to support system functionality.
I recommend this. It'd be nice to see a common OS distro actually do it. For a system-only Python lockdown you should remove distutils and pip to prevent anyone from easily installing anything that isn't a distro package into it. Possibly even removing its site-packages directory and sys.path entry all together (things your distro needs to install could mix directly with the stdlib packages)
/usr/bin/python2 and /usr/bin/python3 then would be user tools, with all the goodness they currently have.
It's never gotten much farther than musings, but protecting the system against the weird things people install would be a good thing. OTOH, this feels a lot like virtual environments so maybe there's something useful to be mined there.
While people sometimes suggest virtualenv as a solution for this. It isn't really the same thing. It isn't a hermetic clone of the original interpreter. It copies the main binary but symlinks back to much of the stdlib. So any existing virtualenv can be an out of date unsupported mix of both after the original interpreter is updated. This has caused users problems in the past with some minor version updates where an internal non-public API used between some binary and a stdlib module was updated as part of a bugfix. Suddenly they didn't match up for existing virtualenvs. virtualenv is an amazing hack that I promote to most anyone for their own applications use with the occasional known caveats (solvable by regurly rebuilding your virtualenvs)... But I wouldn't want to see it used for the core OS itself even though it sounds better at first glance. -gps