embedding python in C, working but with exception at the end

[jepler at unpythonic.net]

I see a couple of problems.  First, because I'm using Unix, where filenames are
case-sensitive, I had to '#include "Python.h"' instead of '#include
"python.h"'.

Next, it looks like the behavior that '.' is placed on sys.path isn't done
automatically when embedding.  So I had to set the environment variable
"PYTHONPATH=." since Test.py was in the current directory.

Before I did this, I got this output:
	Exception exceptions.ImportError: 'No module named Test' in 'garbage
		collection' ignored
	Fatal Python error: unexpected exception during garbage collection
	Aborted
which was a clue about the problem you were running into.  This ImportError was
being caused back at PyImport_Import but was being transmuted into a fatal
error down at Py_Finalize().  By adding 'else { PyErr_Print(); }' to the end of
'if(mod)', I got the error message printed and cleared.  Now, garbage
collection which is kicked off by Py_Finalize() doesn't find the existing error
condition and treat it as a fatal error.

In your code, 'rslt' will be a Python Integer, not a Python Float, so
PyFloat_AsDouble will fail.  You could either write something like
	if (rslt)
	{       
		if(PyFloat_Check(rslt)) {
		    answer = PyFloat_AsDouble(rslt);    
		} else {
		    printf("not a float\n");
		    answer = 1.0;
		}
		Py_XDECREF(rslt);
	}
instead, or use PyErr_Check() + PyErr_Print() or PyErr_Clear().
If you want to accept integer or float returns, then maybe you want
	if(PyFloat_Check(rslt)) { answer = PyFloat_AsDouble(rslt); }
	else if(PyInt_Check(rslt)) { answer = PyInt_AsLong(rslt); }
	else probably not a numeric type

Jeff
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