`esys:Unixqueue.event_system ->
mode:Ftp_data_endpoint.transmission_mode ->
local_sender:Ftp_data_endpoint.local_sender ->
descr:Unix.file_descr ->
unit ->
object
method abort : unit -> unit
method descr : Unix.file_descr
method descr_state : descr_state
method event_system : Unixqueue.event_system
method local_sender : Ftp_data_endpoint.local_sender
method request_notification : (unit -> bool) -> unit
method state : unit Uq_engines.engine_state
end`