Using Python threads in an embedded application

[Jody]

I'm have problems with SWIG 1.3.10, python 2.2 and Python threads.
The symptom is that the first time a program is loaded the static
method _wrap_Test_getInstance works and the function exits without
error.  However the second time _wrap_Test_getInstance is invoked
SWIG_NewPointerObj is returns 0.

Here's the runtime error message:

Traceback (most recent call last):
  File "<string>", line 2, in ?
  File "./startRecording.py", line 2, in ?
    test = Test.Test_getInstance()
  File "./Test.py", line 33, in __init__
    self.this = this
  File "./Test.py", line 8, in __setattr__
    if isinstance(value,Test):
TypeError: 'NoneType' object is not callable
Exception exceptions.TypeError: "'NoneType' object is not callable" in  ignored

Before I turn a bug report into SWIG, am I using Python threads
correctly as shown by the following code fragement?

#include "Python.h"

#include "Test.hpp"

static PyThreadState *globalThreadState = 0;

extern "C"
{
   void initTestc(void);
}

void
initializePython(int argc, char **argv)
{
   // Begin critical section
   if (globalThreadState == 0) 
   {
      /* Add static modules */
      PyImport_AppendInittab("Testc", initTestc);

      /* Initialize the Python interpreter.  Required. */
      Py_Initialize();

      PySys_SetArgv(argc, argv);

      /* Create and acquire the lock */
      PyEval_InitThreads();

      /* Release the thread state */
      globalThreadState = PyEval_SaveThread(); 
   }
   // end critical section
}

void
finalizePython()
{
   if (globalThreadState)
   {
      PyEval_AcquireThread(globalThreadState);
      globalThreadState = 0;
      Py_Finalize();
   }
}

static char startRecordingCommand[] = "\
try: \n\
   import startRecording \n\
except ImportError: \n\
   print 'startRecording.py not found' \n\
";

void 
startRecording(int argc, char **argv)
{
   PyEval_AcquireLock();

   PyThreadState *threadState = Py_NewInterpreter();
   if (threadState == 0) 
   {
      fprintf(stderr, "Sorry -- can't create an interpreter\n");
      return;
   }

   PySys_SetArgv(argc, argv);

   PyRun_SimpleString(startRecordingCommand);

   Py_EndInterpreter(threadState);

   PyEval_ReleaseLock();
}

int 
main(int argc, char **argv)
{
   initializePython(argc, argv);
   startRecording(argc, argv);
   startRecording(argc, argv);
   finalizePython();
}