Procedure NTDSC (
	Lun: Integer;
	EFN: Event_flag;
	MSG: CH16;
	VAR IOSB: IO_Status_block
	);
   EXTERNAL;
{*USER*
Disconnect the network logical link active on LUN, and free the LUN. Unlike
NTABT, pending transmits are allowed to complete before the link is shut down.
Pending receive messages continue to be delivered until all transmits are
gone, then any remaining are aborted. MSG is user data sent to remote task.
}