val read :
?recursive:bool ->?init:string ->?on_error:((string * failure)-> unit)->?timeout:float ->priority:'a->'ascheduler->socket->marker->((string * string option)-> unit)->
unit
val write :
?exec:(unit -> unit)->?on_error:(failure-> unit)->?bigarray:bigarray->?string:string ->?timeout:float ->priority:'a->'ascheduler->socket->
unit