...one of the most highly
regarded and expertly designed C++ library projects in the
world. — Herb Sutter and Andrei
Run the io_service's event processing loop to execute ready handlers.
std::size_t poll( boost::system::error_code & ec);
The poll() function runs handlers that are ready to run, without blocking, until the io_service has been stopped or there are no more ready handlers.
Set to indicate what error occurred, if any.
The number of handlers that were executed.