Methods and devices for recording or reading files on/from a sequential medium and sequential medium
AssigneeKoninklijke Philips Electronics N.V.
InventorsRonald Marcel Tol, Gerrit Jan Scholl, Wilhelmus Jacobus Van Gestel, Steven Broeils Luitjens
Life of this patent
Estimating the term…
Abstract
The invention relates to a method and a device for reading and a method and a device for recording files on a sequential medium as well as the sequential medium itself. In order to enable the use of sequential write-once mediums according to the invention the file system descriptor pointing to a current version of a management information area is recorded on a reserved track being located at the beginning of the volume. Thereby, the management information area is recorded at a location behind files being recorded onto the volume.
Claims10
A method for recording files on a sequential medium (1), said method comprising the steps of
- a) recording a management information area (20, 21) storing data structures that are used for volume and file management and
- b) recording files onto the volume characterized by
- c) recording the management information area (20, 21) at a location behind said files and
- d) recording a file system descriptor (18, 19) pointing to the current version of the management information area (20, 21) onto a reserved track (14) being located at the beginning of the volume.
A method for reading files from a sequential medium, said method comprising the steps of
- a) reading a management information area (20, 21) storing data structures that are used for volume and file management and
- b) then reading files from the volume characterized by
- c) reading first a reserved track (14) containing a file system descriptor (18, 19) and being located at the beginning of the volume and
- d) reading then the management information area (20, 21) from a location behind said files using the file system descriptor (18, 19) pointing to the current version of the management information area (20, 21).
A device for recording files on a sequential medium (1) comprising recording means for recording a management information area (20, 21) storing data structures usable for volume and file management and for recording files onto a volume characterized by
- programmable microprocessor means being connected to the recording means and being programmed in order to cause the recording means to record said management information area (20, 21) at a location behind said files and to record a file system descriptor (18, 19) pointing to the current version of the management information area (21) onto a reserved track (14) at a location at the beginning of the volume.
A device for reading files from a sequential medium comprising reading means for reading a management information area (20, 21) storing data structures that are used for volume and file management characterized by
- programmable microprocessor means being connected to the reading means and being programmed in order to cause the reading means to read a reserved track (14) containing a file system descriptor (18, 19) and being located at the beginning of the volume and then to read the management information area (20, 21) from a location behind said files by means of the file system descriptor (18, 19) pointing to the current version of the management information area (21).
Sequential medium comprising a management information area storing data structures that are used for volume and file management and for reading files from a volume and a logical volume containing files
- characterized in that it further comprises a reserved track to record a sequence (17) of file system descriptors (18, 19), the latest file system descriptor (18, 19) pointing to a current version of the management information area (20, 21), the reserved track being located near by a lead-in area (12) of the medium,
- the current version of the management information area (21) is located at the end of the files recorded on the medium, said files being located between the reserved track (14) and the current version of the management information area (21).
Dependencies are inferred from the claim text.