On Sat, Aug 19, 2006 at 09:08:21AM -0700, Bryan wrote: > Jack Diederich wrote: > > On Fri, Aug 18, 2006 at 02:21:40PM -0700, Bryan wrote: > >> i've written a program that uses python c api code that lives in a > >> shared library that is loaded by a custom apache module (mod_xxx). this > >> python c api code all works correctly under our test server and under > >> apache but only if mod_python isn't loaded. when apache loads > >> mod_python as shown in the http.conf snippet below, > >> PyThreadState_Swap(NULL) in mod_xxx returns NULL. when the snippet of > >> code in http.conf is commented out, it works again. what do i have to > >> do to have mod_xxx code work correctly when apache loads mod_python? > >> > >> > >> failure case when apache loads mod_python: > >> Py_Initialize() succeeded > >> PyThreadState_Swap(NULL) failed > >> > >> > >> sucess case when apache doesn't load mod_python: > >> Py_Initialize() succeeded > >> PyThreadState_Swap(NULL) succeeded > >> > > > > Running multiple python interpreters in the same process isn't supported. > > It works OK for most things but some low-level guts are shared between > > interpreters so it is possible to run into trouble. > > > > You aren't running multiple interpreters in the same process. You and > > mod_python both think you are in charge and end up nuking each other's > > states. Py_Initialize() resets the global state and shouldn't be called > > more than once. You can create more than one sub-interpreter (check out > > the mod_python source for how, the source is small and readable). > > > > The best thing to do would be to load your module last and conitionally > > call Py_Initialize() if someone else hasn't already. > > > > -Jack > > > thanks for replying jack. i tested what you suggested. > > i put our module after mod_python, commented out Py_Initialize(), and > Py_IsInitialized() returned True, but PyThreadState_Swap() failed. > > i put our module before mod_python, called Py_Initialize(), and > Py_IsInitialized() returned True, but PyThreadState_Swap() failed. > > i removed mod_python and our module succeeded. > > i even tested combinations of calling and PyEval_InitThreads() but didn't > work > either.
I'm out of my depth here, I only know that this kind of thing is tricky. I think you need to explicitly spawn a new sub-interpreter or at least a new thread state from the existing interpreter. Your best bet is to ask on the mod_python mailing list. Those guys actually do this kind of thing so if you are going to get good advice it will be from them. -Jack -- http://mail.python.org/mailman/listinfo/python-list
