[Python-Dev] Python and the Linux Standard Base (LSB)

[Robin Bryce]

On 28/11/06, "Martin v. Löwis" <martin at v.loewis.de> wrote:
> I personally agree that "Linux standards" should specify a standard
> layout for a Python installation, and that it should be the one that
> "make install" generates (perhaps after "make install" is adjusted).
> Whether or not it is the *LSB* that needs to specify that, I don't
> know, because the LSB does not specify a file system layout. Instead,
> it incorporates the FHS - which might be the right place to define
> the layout of a Python installation. For the LSB, it's more import
> that "import httplib" gives you something working, no matter where
> httplib.py comes from (or whether it comes from httplib.py at all).

Yes, especially with the regard to the level you pitch for LSB. I
would go as far as to say that if this "contract in spirit" is broken
by vendor repackaging they should:
  * Call the binaries something else because it is NOT python any more.
  * Setup the installation layout so that it does NOT conflict or
overlap with the standard layout.
  * Call the whole package something else.

But I can't see that happening.

Is it a bad idea to suggest that: Python grows a vendor_variant
attribute somewhere in the standard lib; That its content is
completely dictated by a new ./configure argument which is the empty
string by default; And, request that it is left empty by re-packagers
if the installation is 'reasonably standard' ?

I would strongly prefer _not_ write code that is conditional on such
an attribute. However if there was a clear way for a vendor to
communicate "This is not a standard python runtime" to the python run
time, early failure (in the application) with informative error
messages becomes much more viable.

Eg sys.vendor_variant would be orthogonal to sys.version and sys.version_info

Given:
python -c "import sys; print sys.version"
GCC 4.1.2 20060928 (prerelease) (Ubuntu 4.1.1-13ubuntu5)

A regex on sys.version does not seem like a good way to get positive
confirmation I'm using the "Canonical" variant (pun intended)

python -c "from distutils.util import get_platform; print get_platform()"
Tells me nothing about the vendor of my linux distribution. Except,
ironically, when it says ImportError

Cheers,
Robin