InitializerDispatch
init(type:io:queue:cleanupHandler:)
convenience init(type: DispatchIO.StreamType, io: DispatchIO, queue: DispatchQueue, cleanupHandler: @escaping (Int32) -> Void)InitializerDispatch
convenience init(type: DispatchIO.StreamType, io: DispatchIO, queue: DispatchQueue, cleanupHandler: @escaping (Int32) -> Void)