Ticket #3254: serial_test.cpp

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

void writeComplete(const boost::system::error_code & ec, size_t transferred)
{
        if (ec)
        {
                // cancel was called before the io_service was entered. I would 
                // expect an operation aborted error
                std::cout << "operation cancelled" << std::endl;
        }
        else
        {
                std::cout << transferred << " bytes transferred (not cancelled!)" << std::endl;
        }
}

int main(int argc, char * argv[])
{
        boost::asio::io_service my_io_service;
        char msg[] = {'h', 'e', 'l', 'l', '0', 0};

        {
                boost::asio::serial_port port(my_io_service, "/dev/ttyS1");

                // serial port is opened and we initiate an async write to probe for a device
                // attached
                boost::asio::async_write(port, boost::asio::const_buffers_1(msg, sizeof(msg)), writeComplete);

                // assume elsewhere in the code an error occurred, and we cancel all processing
                port.cancel();

                // the cleanup of the error also causes the serial port to be destroyed.
        }

        // meanwhile the error cleanup has completed and we're ready to continue without using
        // the serial port
        std::cout << "entering io_service" << std::endl;

        my_io_service.run();
}