Fastq.MakeIOval read : Future.Reader.t -> item Core_kernel.Or_error.t Future.Pipe.Reader.tval write :
Future.Writer.t ->
item Future.Pipe.Reader.t ->
unit Future.Deferred.tval write_file :
?perm:int ->
?append:bool ->
string ->
item Future.Pipe.Reader.t ->
unit Future.Deferred.t