`sig
exception Closed
type 'a polypipe
val create :
int -> 'a Netsys_polypipe.polypipe * 'a Netsys_polypipe.polypipe
val length : 'a Netsys_polypipe.polypipe -> int
val eof : 'a Netsys_polypipe.polypipe -> bool
val read : nonblock:bool -> 'a Netsys_polypipe.polypipe -> 'a option
val write :
nonblock:bool -> 'a Netsys_polypipe.polypipe -> 'a option -> unit
val close : 'a Netsys_polypipe.polypipe -> unit
val set_read_notify : 'a Netsys_polypipe.polypipe -> (unit -> unit) -> unit
val set_write_notify :
'a Netsys_polypipe.polypipe -> (unit -> unit) -> unit
val read_descr : 'a Netsys_polypipe.polypipe -> Unix.file_descr
val write_descr : 'a Netsys_polypipe.polypipe -> Unix.file_descr
val set_exception : 'a Netsys_polypipe.polypipe -> exn -> unit
val get_exception : 'a Netsys_polypipe.polypipe -> exn option
module Debug : sig val enable : bool Stdlib.ref end
end`