dlib C++ Library - threaded_object_ex.cpp

    /*

        This is an example illustrating the use of the threaded_object
        from the dlib C++ Library.

        This is a very simple example.  It creates a single thread that
        just prints messages to the screen.
    */

    #include <iostream>
    #include "dlib/threads.h"
    #include "dlib/misc_api.h"  // for dlib::sleep

    using namespace std;
    using namespace dlib;

    class my_object : public threaded_object
    {
    public:
        my_object()
        {
            // Start our thread going in the thread() function
            start();
        }

        ~my_object()
        {
            // Tell the thread() function to stop.  This will cause should_stop() to
            // return true so the thread knows what to do.
            stop();

            // Wait for the thread to stop before letting this object destruct itself.
            // Also note, you are *required* to wait for the thread to end before
            // letting this object destruct itself.
            wait();
        }

    private:

        void thread()
        {
            // This is our thread.  It will loop until it is told that it should terminate.
            while (should_stop() == false)
            {
                cout << "hurray threads!" << endl;
                dlib::sleep(500);
            }
        }
    };

    int main()
    {
        // Create an instance of our threaded object.
        my_object t;

        dlib::sleep(4000);

        // Tell the threaded object to pause its thread.  This causes the
        // thread to block on its next call to should_stop().
        t.pause();

        dlib::sleep(3000);
        cout << "starting thread back up from paused state" << endl;

        // Tell the thread to unpause itself.  This causes should_stop() to unblock
        // and to let the thread continue.
        t.start();

        dlib::sleep(4000);

        // Let the program end.  When t is destructed it will gracefully terminate your
        // thread because we have set the destructor up to do so.
    }