object
  method private cleanup : unit
  method destroy : unit
  method fake_io : Unix.file_descr -> unit
  method iter : bool -> unit
  method on_readable : Unix.file_descr -> (event -> unit) -> event
  method on_timer : float -> bool -> (event -> unit) -> event
  method on_writable : Unix.file_descr -> (event -> unit) -> event
  method readable_count : int
  method private register_readable :
    Unix.file_descr -> (unit -> unit) -> unit Lazy.t
  method private register_timer :
    float -> bool -> (unit -> unit) -> unit Lazy.t
  method private register_writable :
    Unix.file_descr -> (unit -> unit) -> unit Lazy.t
  method timer_count : int
  method transfer : abstract -> unit
  method writable_count : int
end