[Python-Dev] vendor-packages directory

[Bob Ippolito]

On Sep 22, 2005, at 3:04 PM, Rich Burridge wrote:

> Phillip J. Eby wrote:
>
>>> Recently I asked about the inclusion of a "vendor-packages"
>>> directory for Python on the Python mailing list.
>>>
>>> See the thread started at:
>>>
>>>
>>> http://mail.python.org/pipermail/python-list/2005-September/ 
>>> 300029.html
>>>
>>> for the full reasoning behind this request, and the replies
>>> I received.
>>>
>>
>>
>> I'm with Terry on this, it needs a better rationale.  Why can't  
>> you just
>> add a .pth file to the site-packages directory?  It seems that would
>> address the issue nicely.
>>
>> (See http://docs.python.org/lib/module-site.html for documentation of
>> the .pth mechanism, which would let you implement a separate
>> vendor-packages directory without modifying Python, and would still
>> allow local overrides of your vendor packages.)
>>
>
> I understand how .pth files work.
>
> The rationale for requesting the "vendor-packages" approach, is  
> that Python files,
> as supplied by the vendor (Sun, Apple, RedHat ...)  with their  
> operating system
> software, should go in a totally separate base directory, to  
> differentiate them
> from Python files installed specifically at one site.

Note that Apple already does this via a .pth file ("Extras.pth"), as  
of Mac OS X 10.4, which points to the following location:
/System/Library/Frameworks/Python.framework/Versions/2.3/Extras/lib/ 
python

Currently this location includes wxPython.  There is an additional  
vendor package which they (wrongly) integrated into their patched  
Python build process so it ends up in the plat-mac subsection of the  
standard library (CoreGraphics).  This is a closed-source not-very- 
well-done SWIG generated CoreGraphics wrapper that they use for some  
print filters and such.

Note that Python does have additional support on Mac OS X for an  
additional per-user site directory out of the box (for framework  
style builds anyway):
~/Library/PythonX.Y/site-packages/

There's also the admin-writable /Library/PythonX.Y/site-packages/,  
but that's an implementation detail in that Apple made site-packages  
a symlink to that location.

-bob