Method push

listings/listing_c.1.cpp:30–35

    public:
        template<typename T>
        void push(T const& msg)
        {
            std::lock_guard<std::mutex> lk(m);
            q.push(std::make_shared<wrapped_message<T> >(msg));
            c.notify_all();
        }
        std::shared_ptr<message_base> wait_and_pop()
        {
            std::unique_lock<std::mutex> lk(m);