boost-asio-ticker-example

boost_asio_ticker.cpp

// environment:   C++14, gcc-11.2
// build command: g++ -o ./boost_asio_ticker boost_asio_ticker.cpp -lpthread

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

class Ticker {
public:
    Ticker(boost::asio::io_context &io, const std::chrono::seconds& interval, std::function<void()> handler)
            : timer_(io, interval)
            , interval_(interval)
            , handler_(std::move(handler)) {
    }

    void async_start() {
        timer_.async_wait([&](const boost::system::error_code ec) {
            on_tick(ec);
        });
    }

    void on_tick(const boost::system::error_code ec) {
        handler_();
        timer_.expires_from_now(interval_);
        timer_.async_wait(boost::bind(&Ticker::on_tick, this, boost::asio::placeholders::error));
    }

    size_t stop() {
        return timer_.cancel();
    }

private:
    boost::asio::steady_timer timer_;
    std::chrono::seconds      interval_;
    std::function<void()>     handler_;
};

void print() {
    std::cout << "Hello, World!" << std::endl;
}

int main()
{
    boost::asio::io_context io;

    using namespace std::chrono_literals;
    auto interval = 3s; // (since C++14)

    Ticker t(io, interval, print);
    t.async_start();

    io.run();
    return 0;
}