JPH04361339A - File managing system for draw type optical disk - Google Patents

Abstract

PURPOSE:To provide the file managing system which can retrieve valid directory information at high speed concerning a DRAW type optical disk. CONSTITUTION:A file name 21, start value 22 and end value 23 of an address in a data area 3 for the data of the file name are existent in a directory area 2. This information is added and registered each time a file is prepared. A sequential number 11 of a valid directory in the directory area 2 and a head sequential number 12 for an empty data area in the data area 3 are existent in a directory managing area 1. It can be directly recognized from the sequential number 11 of the directory where the latest directory information is.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a file management system for a write-once optical disc, and more particularly to a file management system for a write-once optical disc having a directory management area.

0002

[Prior Art] A conventional file management system for write-once optical discs includes a file name, directory information including address information where the data given the file name exists, and file address table information indicating the order in which the data is stored. It has a mixed directory area and a data area where data exists.

[0003] In such conventional file management systems for write-once optical discs, it is necessary to additionally register directory information each time a file is created during the file creation process, but once the information is written, it cannot be erased. If the same directory information exists, the one written last is determined to be the latest information, and the directory information is determined to be valid or invalid.

0004

[Problem to be Solved by the Invention] In this conventional file management system for write-once optical discs, when multiple pieces of directory information exist, the one written last among them is judged as the latest information. directory information needed to be searched. For this reason, it is difficult to judge whether a directory is valid or invalid, and it also takes time to search for a valid directory.

[0005]

[Means for Solving the Problems] A file management method for a write-once optical disc of the present invention provides a directory area having a file name of a non-rewritable write-once optical disc and address information in which data to which this file name is assigned exists. and a data area in which the data exists, the file management method for a write-once optical disc includes information on whether information in the directory area is valid or invalid and information on a free start address of the data area. It has a directory management area.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a diagram for explaining the internal structure of a write-once optical disc according to an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a directory management area, which has a sequential number 11 of a valid directory in a directory area 2 and a leading sequential number 12 of a free data area in a data area 3. The directory area 2 has a file name 21 given to data, and a start value 22 and an end value 23 of the address at which the data given the file name exists in the data area 3. Data area 3 contains data.

In the directory management area 1, where in the directory area 2 the latest directory information is located is determined from the directory sequential number 11, and a valid directory is directly searched for without checking all the directories.

0010

Effects of the Invention As explained above, the present invention provides a file management system that includes a directory area having a file name and address information where data to which the file name is assigned exists, and a data area where the data exists. By having a directory management area that has information on whether the directory area information is valid or invalid and information on the free start address of the data area, it has the effect of speeding up file addition and retrieval.

[Brief explanation of the drawing]

FIG. 1 is a diagram for explaining the internal structure of a write-once optical disc according to an embodiment of the present invention.

[Explanation of symbols]

1 Directory management area 2 Directory area 3 Data area

Claims (1)

[Claims] Claim 1: A write-once optical disc that is not rewritable and includes a directory area that has a file name of a write-once optical disc, address information where data given the file name exists, and a data area where the data exists. A write-once optical disc characterized by a file management system for an optical disc, comprising a directory management area having information as to whether the information in the directory area is valid or invalid and information as to the free start address of the data area. File management method.