Title:
【発明の名称】消去不可能な記憶媒体上にファイルを読出しかつ書込む方法
Document Type and Number:
Japanese Patent JPH04504018
Kind Code:
A
Abstract:
A method of inputting and outputting information files between a computer memory and a write-once medium in which a cache memory is established as an intermediary between an operating system's transfer address and the medium. The cache includes a system file allocation structure in a format corresponding to that for erasable media and a media directory file area. The directory in the write-once medium is read to the cache and the system file allocation structure is constructed from the directory information. When performing an operating system command, such as a read or write, access to the medium is made via the cache memory. For example, when reading a data file, sector locations indicated by the system file allocation structure are first mapped to corresponding sectors in the medium directory file area and the corresponding sectors are read from the medium. When writing a data file, sectors containing new data are identified, old sectors on the medium are marked, and only the new sectors are written to the medium with pointers linking them to the unchanged sectors.
Inventors:
Shoe pack, louis h
Application Number:
JP50441690A
Publication Date:
July 16, 1992
Filing Date:
February 23, 1990
Export Citation:
Assignee:
Drexler Technology Corporation
International Classes:
G06F3/06; G06F12/00; G06F12/08; G11B20/10; G11B27/32; (IPC1-7): G06F3/06; G06F12/00
Attorney, Agent or Firm:
Hisami Fukami (4 outside)