(DOS) The name of a number of {operating systems} which include facilities for storing files on disk. Such a system must handle physical disk I/O, the mapping of file names to disk addresses and protection of files from unauthorised access (in a multi-user system). A DOS should present a uniform interface to different storage device such as floppy disks, hard disks and {magnetic tape} drives. It may also provide some kind of locking to prevent unintentional simultaneous access by two processes to the same file (or record). (1998-07-08)
