[Distutils] Shared libs with setuptools/distutils ?

[Phillip J. Eby]

At 06:11 PM 3/7/2008 -0800, Andi Vajda wrote:
>If I want to support multiple Python extension modules built with 
>JCC to run in the same Python process and hence share the same Java 
>VM, there is some code between these modules that needs to be shared.
>
>Currently, the JCC runtime code (not much, really) is compiled into 
>each JCC-built extension module. There is one C++ class, JCCEnv, 
>that really needs to be shared among all JCC-built modules. Building 
>that class into a shared library (instead of a python module 
>library) could be to be the way to go. Then every such module would 
>be linked against this shared library.
>
>I gave this a quick manual try on Mac and it seems to work.
>
>But do distutils or setuptools have built-in ways of building a 
>regular shared library (in particular, on Mac OS X, a .dylib, not a 
>bundle) or is there some hacking needed there still ? (google shows 
>that there have been nibbles of interest over the past years about 
>this but it's unclear whether this was done or not). It would make 
>the JCC build considerably more complicated if I had to add 
>hand-crafted code for each and every platform/compiler that is 
>supported by JCC (that list is growing). Having a distutils or 
>setuptools way of building a regular shared library would be very 
>helpful here. Has support for that that been added yet ?

Not really, but there is some experimental code in the setuptools 
trunk, IIRC.  If you look at the 'tests/test_shlib' subdirectory 
there is some sample code for building a shared library.  I don't 
know if it works right on OS X...  and there were some hairy things 
involved in doing it on Linux.  Patches welcome.  :)

(Chances are good, though, that you'll be better off using the import 
+ API struct approach to sharing stuff.  IIRC, there are still a lot 
of hoops to jump through to get shared libs working on OS X and Linux.)