|  | 
Spawn a new coroutined-based thread of execution.
template< typename Executor, typename AwaitableExecutor, typename CompletionToken = DEFAULT> DEDUCED co_spawn( const Executor & ex, awaitable< void, AwaitableExecutor > a, CompletionToken && token = DEFAULT, constraint_t<(is_executor< Executor >::value||execution::is_executor< Executor >::value) &&is_convertible< Executor, AwaitableExecutor >::value > = 0);
The executor that will be used to schedule the new thread of execution.
                The awaitable
                object that is the result of calling the coroutine's entry point
                function.
              
The completion token that will handle the notification that the thread of execution has completed. The function signature of the completion handler must be:
void handler(std::exception_ptr);
void(std::exception_ptr)
asio::awaitable<void> echo(tcp::socket socket) { try { char data[1024]; for (;;) { std::size_t n = co_await socket.async_read_some( asio::buffer(data), asio::use_awaitable); co_await asio::async_write(socket, asio::buffer(data, n), asio::use_awaitable); } } catch (const std::exception& e) { std::cerr << "Exception: " << e.what() << "\n"; } } // ... asio::co_spawn(my_executor, echo(std::move(my_tcp_socket)), asio::detached);
          The new thread of execution is created with a cancellation state that supports
          cancellation_type::terminal values only. To change the cancellation
          state, call this_coro::reset_cancellation_state.