On Jun 27, 8:22 am, Tim Spens <[EMAIL PROTECTED]> wrote: > Hello all, > > I've been trying to get an example found > herehttp://codeidol.com/python/python3/Embedding-Python/Registering-Callb... > to work. Every thing works fine except when I try to trigger an event from c > that will call a python function. Here is my test code: > > //-----------------------python code--------------------------// > #! /usr/bin/env python > import time > import callback > > def callback1(label,count): > print 'callback1 successfully triggered from python via callback.so' > return 'callback1 => %s number %i' % (label, count) > > def callback2(label,count): > return 'callback2 => ' + label * count > > print '\nTest1:' > callback.setHandler(callback1) > callback.triggerEvent() # simulate events caught by C layer > > print '\nTest2:' > callback.setHandler(callback2) > > print 'Waiting for callback2 to be called from c:' > while 1: > time.sleep(.001) > > //-----------------------c code-------------------------------// > #include <Python.h> > #include <stdlib.h> > > /* keep Python object in C */ > static PyObject *Handler = NULL; > > void Route_Event(char *label, int count){ > char *cres; > PyObject *args, *pres; > /* call Python handler */ > args = Py_BuildValue("(si)", label, count); > pres = PyEval_CallObject(Handler, args); > Py_DECREF(args); > if (pres != NULL){ > /* use and decref handler result */ > PyArg_Parse(pres, "s", &cres); > printf("%s\n", cres); > Py_DECREF(pres); > > }} > > // the actual python callback call > static PyObject * > make_call(PyObject *function, PyObject *args){ > if (function == NULL) return NULL; > PyObject * val = PyObject_CallObject(function, args); > Py_XDECREF(args); > return val; > > } > > static PyObject * > Register_Handler(PyObject *self, PyObject *args){ > /* save Python callable object */ > Py_XDECREF(Handler); > PyArg_Parse(args, "O", &Handler); > Py_XINCREF(Handler); > Py_INCREF(Py_None); > return Py_None; > > } > > static PyObject * > Trigger_Event(PyObject *self, PyObject *args){ > /* let Python simulate event caught by C */ > static int count = 0; > Route_Event("spam", count++); > Py_INCREF(Py_None); > return Py_None; > > } > > static struct PyMethodDef callback_methods[] = { > {"setHandler", Register_Handler}, /* name, address */ > {"triggerEvent", Trigger_Event}, > {NULL, NULL}}; > > /* on first "import callback" */ > void initcallback(){ /* this is called by Python */ > (void) Py_InitModule("callback", callback_methods); > > } > > int main(){ > while (1){ > printf("1\n"); > //attempting to call callback2 which is registered to Handler > //i've also tried args = Py_BuildValue("(si)", label, count); > here but I get a segfault. > PyObject *args = Py_BuildValue("s","c code"); > printf("2\n"); > PyObject* val = make_call(Handler,args); > printf("3\n"); > Py_XDECREF (val); > printf("4\n"); > sleep(1); > > }} > > //------------------------compiler stuff----------------------// > gcc callback.c -c -g -Wall -fpic -I /usr/include/python2.5 -o callback.o > gcc callback.c -g -Wall -I /usr/include/python2.5 -L /usr/local/lib > -lpython2.5 -o callback > gcc -shared -Wall callback.o -o callback.so > > //------------------------test code results-------------------// > ../callback.py > Test1: > callback1 successfully triggered from python via callback.so > callback1 => spam number 0 > > Test2: > Waiting for callback2 to be called from c: > #NOTHING EVER GETS PRINTED HERE CALLBACK NEVER GETS CALLED? > > ../callback > 1 > 2 > 3 > 4 > .... > > Thanks, > Tim
Maybe you just need to flush the stdout buffer in python. `sys.stdout.flush()` Matt -- http://mail.python.org/mailman/listinfo/python-list
