Thank's a lot miki for your response! It seems that this problem is now solved, yet a new one now occured. And the name of my new problem is...
"<Stack is not available: Cannot access memory at address 0x1.>" Let me rewrite the code a little bit more clearly... //******************************************************************* // C O D E //******************************************************************* 01 //___________________________________________________________________ 02 // Includes mpla, mpla mpla... 03 #include <Python.h> 04 #include <iostream> 05 #include <cmath> 06 using namespace std; 07 08 //___________________________________________________________________ 09 // My function 10 /* Return the sqrt of a double */ 11 static PyObject* Fotis_root(PyObject *self, PyObject *args) 12 { 13 double d=0; 14 if(!PyArg_ParseTuple(args,"d",&d)) return NULL; 15 return Py_BuildValue("d", sqrt(d)); 16 } 17 18 //___________________________________________________________________ 19 // Some python module stuff 20 static PyMethodDef FotisMethods[] = { 21 {"root",Fotis_root, METH_VARARGS, 22 "Return the root of a double."}, 23 {NULL, NULL, 0, NULL} 23 }; 24 25 //___________________________________________________________________ 26 // Main program 27 int main(int argc,char** argv) 28 { 29 Py_Initialize(); 30 Py_InitModule("fotis", FotisMethods); 31 PyRun_SimpleString("from fotis import root"); 32 FILE* fp=stdin; 33 char *filename="Solver"; 34 PyRun_InteractiveLoop(fp,filename); 35 Py_Finalize(); 36 return 0; 37 } Now lets say i set two breakpoints: line 29, and line 13. This is what happens: 1. Breakpoint at line 29: There is a strange combination of next, step, and other stuff that can move me from line 29 to line 34. No matter how deeply I digged everywhere I cannot realy understand what really happens there, but what the hack this is not what I'm really interested in. by the way if i try too many steps then there is no way back... 2. Breakpoint at line 13: When I finally reach the much awaited line 34, the python interpreter is there and running and waiting for my commands, which here is the fotis.root(double) command. when I give though this command control is totally lost: i get the message described above and after that everything seems to be dead. I really do not know where I am, why am I there, and what exactly I am doing at the point that I am. What is really happening? Any help will be very appreciated. fotis._ -- http://mail.python.org/mailman/listinfo/python-list