Paul J R wrote:

mytest.cpp:

class A { public: A() {} ~A() {} virtual void worker() { std::cout << "I am A worker" << std::endl; } virtual A *factory() { std::cout << "Factory for A class called" << std::endl; return new A; } virtual void operator()() { std::cout << "Calling A operator()" << std::endl; worker(); } void threadcontroller() { boost::thread_group thre; for(;;) { std::cout << "I am in the A.threadcontroller() method" << std::endl; A *mea = factory(); mea->worker(); thre.create_thread(*mea); exit(0); } } };

class B: public A { public: B() {} ~B() {} virtual void worker() { std::cout << "I am B worker" << std::endl; } virtual void operator()() { std::cout << "Calling B operator()" << std::endl; worker(); } B *factory() { std::cout << "Factory for B class called" << std::endl; return new B; } };

int main() { B meb;

meb.worker(); meb.threadcontroller(); }

Hi Paul, Note that thread_group::create_thread(const boost::function0<void>&) takes a boost::function0<void> as an argument so in case you pass a functor like you do, boost::function will resolve to the operator() of the apparent pointer type (i.e. A::operator()). In order to make this work you need a way to construct a "pointer to member function" which takes into account the actual value of "this". So instead of thre.create_thread(*mea); You want: thre.create_thread(boost::bind(&A::operator(), mea)); For this you need to include boost/bind.hpp. In this case boost::bind will make a functor and when create_thread calls that functor, boost::bind will effectively call mea->operator(). Next thing, you don't want to call exit() right after you create the thread because once your main thread exits the other one will exit too (how soon depends on your OS, in my machine the thread doesn't even get to start before it is killed because the main thread is exiting). So you want to call thre.join_all(); so the main thread sleeps until all the threads are done. So my A::threadcontroller looks like this: void threadcontroller() { boost::thread_group thre; std::cout << "I am in the A.threadcontroller() method" << std::endl; A *mea = factory(); mea->worker(); thre.create_thread(boost::bind(&A::operator(), mea)); thre.join_all(); } Using this A::threadcontroller my output looks like this: I am B worker I am in the A.threadcontroller() method Factory for B class called I am B worker Calling B operator() I am B worker Which is what you want (I think). Also, one nice thing about using boost::bind is that you can use any method as the thread body (i.e. you can rename your operator() to dowork() if you want). Good luck, -delfin