Lwt_engine.poll_basedAbstract class for engines based on a poll-like function.
inherit tmethod private virtual poll : (Unix.file_descr * bool * bool) list -> float -> (Unix.file_descr * bool * bool) listpoll fds tiomeout, where fds is a list of tuples of the form (fd, check_readable, check_writable), waits for either:
check_readable set to true to become readablecheck_writable set to true to become writableand returns the list of file descriptors with their readable and writable status.