JPH07105054A - File management method - Google Patents

Abstract

PURPOSE:To reduce the nonuse part of an external storage device without enlarging the size of an area management table and to effectively use it by providing an area use table managing blocks obtained by subdividing respective area in addition to the area management table, and using the area management table and the area use table jointly. CONSTITUTION:A file information table 1 storing information on a data file, the area management table 2 managing the use state of the storage area of the data file and the area use table 3 managing the use state of the blocks obtained by subdividing the storage area are provided. The area use table 3 has area numbers 8 corresponding to the area numbers 8 of the area management table 2, and the respective area numbers 8a have plural area block numbers 10. Namely, the area storing the data file is divided into the plural blocks, and one area can be shared by the plural files by using the area management table 2 and the use table 3 jointly.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a file management method for an operating system in a computer.

[0002]

2. Description of the Related Art In a conventional file management method for an operating system in a computer, a data file to be stored in a storage medium of an external storage device such as a flexible disk device or a hard disk device is data-stored by an area management table via a file information table. It is managed by connecting the storage areas.

[0003]

The conventional file management method as described above is widely used because it is a simple management method. However, in the last storage area for storing a data file, the data to be stored is to be stored. Even if a file is a small amount, it occupies the entire storage area and eliminates the storage of other data files while leaving a lot of unused areas, thus enabling the storage capacity of the external storage device to be effective. It has the drawback that it cannot be used. Further, in the external storage device having the same storage capacity, if the size of the storage area managed by the operating system is reduced, the size of the area management table becomes relatively large.

[0004]

A file management method of the present invention is an operating system file management method for managing a data file stored in an external storage device based on management information. An information table, an area management table that manages the usage status of the storage area of the data file, and an area usage table that manages the usage status of the used blocks obtained by further subdividing the storage area are provided, and the file information table and the It includes managing the data file by the area management table and the area use table.

That is, the file management method of the present invention is
In a file management method of an operating system for managing a data file stored in an external storage device based on management information, a file information table for storing information of the data file, and an area for managing a usage state of the storage area of the data file A management table and an area usage table for managing the usage status of used blocks in which the storage area is further subdivided are provided, and one data of the external storage device is used by using the area management table and the area usage table together. This includes managing the data file so that the storage area can be shared by a plurality of files.

[0006]

Embodiments of the present invention will now be described with reference to the drawings.

FIG. 1 is a format diagram showing a file information table, an area management table, and an area use table in an embodiment of the present invention.

As shown in FIG. 1, the file information table 1 has a file name portion 4, a start number area portion 5, an end area use information portion 6 and other information storage portion 7. The area management table 2 has an area number 8.
The area use table 3 has an area number 8a corresponding to the area number 8 of the area management table 2, and each area number 8a is
It has a plurality of area block numbers 10.

File name part 4 of file information table 1
The data "FILE-A" stored in the area is used from the area of the number "01" shown in the start number area section 5, and correspondingly, the area number 8 of the area management table 2 is used.
Information 9 stored in the area with the number "01"
As a result, the data storage areas are linked by storing the number "02" which is the number of the area used next to the area of the number "01". Similarly, the number "03"
Each area from "06" to "06" is connected, and the area number 8 is "0".
The table information 9 stored in the area “6” is
The number “FF” indicating the last area used by the data “FILE-A” is stored.

At this time, since the areas "01" to "06" have been used up by the data "FILE-A", the area block number of the area number 8a of the area use table 3 corresponding to these areas. The used area information 11 stored in 10 is "1" indicating that all areas have been used except for the last area block number of number "06". In addition, the data “FI of the file information table 1
The used area information 11a stored in the area block number 10a numbers "1" and "2" of the final area use information section 6 corresponding to "LE-A" is the area block number 10a numbers "1" and "2". It is "1" to indicate that "" has been used.

File name portion 4 of file information table 1
Similarly, the data “FILE-B” stored in the area management table 2 has the area number 8 in the area management table 2 from “07” to
The areas "09" are connected, and the area number 8 stores the number "06" as the final area.

The usage status of the number "06" of the data "FILE-B" is the data "FIL" of the file information table 1.
As shown in the final area use information part 6 corresponding to "EB", the area block number 10a is "1" indicating that the number "3" is being used.

In this way, one area is divided into a plurality of blocks, and each block can be used in a separate file, so that one area can be shared by a plurality of files. It will be possible.

In the above-described embodiment, the number of divisions of one area is four, but it is also possible to set it to five or more or three or less.

As described above, in addition to the conventional area management table, an area use table for managing blocks in which each area is subdivided is provided, and the area management table and the area use table are used in combination to create the area management table. It is possible to reduce the unused portion of the storage area of the external storage device without making the size too large.

[0016]

As described above, according to the file management method of the present invention, the area for storing the data file is divided into a plurality of blocks, and the area use table for managing the usage status of each block is provided. And an area use table are used together so that one area can be shared by a plurality of files, so that an unused area in the storage area of the external storage device can be used without increasing the size of the area management table. There is an effect that the storage capacity of the external storage device can be effectively utilized by reducing the number of parts.

[Brief description of drawings]

FIG. 1 is a format diagram showing a file information table, an area management table, and an area use table in an embodiment of the present invention.

[Explanation of symbols]

 1 File Information Table 2 Area Management Table 3 Area Usage Table 4 File Name Part 5 Start Number Area Part 6 Final Area Usage Information Part 7 Other Information Storage 8.8a Area Number 9 Table Information 10 / 10a Area Block Number 10 11 11a Used area information

Claims (2)

[Claims] 1. A file management method of an operating system for managing a data file stored in an external storage device based on management information, wherein a file information table storing information of the data file and a storage area of the data file are used. An area management table for managing the status and an area usage table for managing the usage status of used blocks obtained by further subdividing the storage area are provided, and a data file is created by the file information table, the area management table, and the area usage table. A file management method comprising managing a file. 2. A file management method of an operating system for managing a data file stored in an external storage device based on management information, wherein a file information table for storing information of the data file and a storage area for the data file are used. The external storage device is provided with an area management table for managing the status and an area usage table for managing the usage status of used blocks obtained by further subdividing the storage area, and using the area management table and the area usage table together. A file management method comprising: managing a data file so that one data storage area can be shared by a plurality of files.