[Boost-users] create threads from within a class

From: Monica Gretzer (mogr_progr_at_[hidden])
Date: 2006-09-27 09:04:10

Hi,
   
  I want to use boost::thread to create threads that are member functions within a class. In all the examples I have seen, the thread function is defined globally.
   
  I explain it with code. The following test code works:
   
  //  code 1: example program that works  -----------------------------------------------
  #include <boost/thread/thread.hpp>
  #include <iostream>
  using namespace std;
   
  void testing()
  {
      cout << "I'm a thread." << endl;
  }
   
  int main(int argc, char* argv[])
  {
       // start a new thread that calls the "testing" function
       boost::thread my_thread(&testing);
       // wait for the thread to finish
       my_thread.join();
   
      return 0;
  }
   
  // -------------------------------------------------------------------------------------------
   
  Now, I want to create something like:
   
  // code 2: thread created from member class (code yields compiler errors)
   
  #include <boost/thread/thread.hpp>
  #include <iostream>
  using namespace std;
   
  class TestThread
  {
  public:
     void testing(void);
     void CreateThread(void);
  };
   
  void TestThread::CreateThread()
  {
      // start a new thread that calls the "testing" function
      boost::thread my_thread(&testing);
      // wait for the thread to finish
      my_thread.join();
  }
   
  int main(int argc, char* argv[])
  {
      TestThread t;
      t.CreateThread();
   
      return 0;    
  }
   
  When compiling the code above (code 2), I get the following compilation error:
  ISO C++ forbids taking the address of an unqualified or paranthesized non-static member function to form a pointer to member function. Say &TestThread::testing.
   
  My question is: How do I create threads from within a C++ class member function?
   
  Thanks a lot for your help.
   
  / Mogr