[Boost-users] boost::asio::steady_timer only firing once

12 Jul 2019


      I am trying to perform a task on an interval and I made a POC using
boost::asio::steady_timer. When I debug it, it only performs the callback
once and does not fire again. I am not sure what I am doing wrong. Any
suggestions?

    // DoMouseEvents.cpp : This file contains the 'main' function. Program
execution begins and ends there.
    //

    #include <boost/asio.hpp>
    #include "boost/asio/deadline_timer.hpp"
    #include<boost/bind.hpp>
    #include <chrono>
    #include <iostream>

    class Pooper
    {
        boost::asio::io_context & m_ioContext;
        boost::asio::steady_timer m_timer;

    public:
        Pooper(boost::asio::io_context & ioContext)
            :
            m_ioContext(ioContext)
            , m_timer(boost::asio::steady_timer(ioContext))
        {
        }

        void Run()
        {
            m_timer.expires_from_now(std::chrono::seconds(5));
            m_timer.async_wait(boost::bind(&Pooper::OnTimerExpired, this,
boost::asio::placeholders::error));
        }

        void OnTimerExpired(const boost::system::error_code & error)
        {
            if (error.failed())
            {
                std::cerr << "boost error: Failed" << std::endl;
            }

            std::cout << "Poop" << std::endl;

            try
            {
                // Move the mouse
                int x = 500;
                int y = 500;
                if (!::SetCursorPos(x, y))
                {
                    int errorCode = GetLastError();
                    std::cerr << "SetCursorPos error: " << errorCode <<
std::endl;
                }

                // Left button down
                x = 65536 * 500;
                y = 65536 * 500;
                ::mouse_event(MOUSEEVENTF_ABSOLUTE | MOUSEEVENTF_LEFTDOWN,
x, y, NULL, NULL);

                // Left button up
                x = 65536 * 500;
                y = 65536 * 500;
                ::mouse_event(MOUSEEVENTF_ABSOLUTE | MOUSEEVENTF_LEFTUP, x,
y, NULL, NULL);

                m_timer.expires_from_now(std::chrono::seconds(5));
                m_timer.async_wait(boost::bind(&Pooper::OnTimerExpired,
this, boost::asio::placeholders::error));
            }
            catch (std::exception &)
            {
                std::cerr << "An exception occured." << std::endl;
            }
        }
    };

    int main()
    {
        boost::asio::io_context ioContext;
        auto pooper = Pooper(ioContext);
        pooper.Run();
        ioContext.run();

        std::cerr << "Exited..." << std::endl;
    }

[Boost-users] boost::asio::steady_timer only firing once

Christopher Pisz