#include <iostream>
#include <boost/thread/thread.hpp>
#include <string>
#include <queue>

class test
{
public:
    test() : finish(false)
    {
        a = boost::thread(&test::thread_func, this);
    }
    ~test()
    {
        {
            boost::unique_lock<boost::mutex> lk(read_write_queue);
            finish = true;
        }
        new_msgs.notify_one();
    }
    void say(std::string m)
    {
        boost::unique_lock<boost::mutex> lk(read_write_queue);
        msgs.push(m);
        new_msgs.notify_one();
    }
private:
    boost::thread a;

    std::queue<std::string> msgs;
    boost::mutex read_write_queue;
    bool finish;
    boost::condition_variable new_msgs;

    void thread_func()
    {
        std::string m;

        while(true)     // !!!
        {
            { // lock begins
                boost::unique_lock<boost::mutex> lk(read_write_queue);
                while(msgs.empty())
                {
                    new_msgs.wait(lk);
                    if(finish)      // to be called on object destruction
                    {
                        lk.unlock();
                        return;
                    }
                }
                m = msgs.front();
                msgs.pop();
            } // end of lock
            std::cout << m << "\n";     // some processing of data
        }
    }
};

int main()
{
    test someone;
    someone.say("cheeze!");
    someone.say("potato!");
    sleep(1);
    return 0;
}