File access control method

Abstract

Abstract PURPOSE: To simplify file management using control records as the index of the file of a volume, by detecting a file to be processed at a high speed by arranging control record on a magnetic tape recording medium. CONSTITUTION: In the data processor equipped with CPU6, main memory unit 7, channel 8, input-output controller 9, and magnetic tape 10, erase area 3 is provided after label of VOLI on magnetic tape recording medium 1 set to magnetic tape 10, and several VOL2 labels 4-1, 4-2...are provided onto this erase area 3. On VOL2 labels 4-1, 4-2..., control records such as head file ordinal number information, tail file ordinal number information and all-file discriminative name information belonging to the corresponding volum are written. To allow each unit higher than magnetic tape 10 to attain access to the file on recording medium 1, contents of VOL2 labels 4-1 and 4-2 are read in to extract the position of the file accessed. COPYRIGHT: (C)1979,JPO&Japio

Inventors

• 👤 Hiroo Imai
• 👤 Masashi Sasada

Bibliographic Details