JPH0635770A - File control system - Google Patents

Abstract

PURPOSE:To treat different kinds of external storage devices in a file control system by one control system. CONSTITUTION:The necessary information for the specification and the access of an external storage device which has conventionally existed within file information, is separated from the file information 1 and is separately controlled as device information 2. As a result, the file information 1 becomes the only logical address information within a device and is treated commonly to each external storage device 4. At the time of performing an actual access, the access is performed by combining the address information within the file information and device information having variable length for each external storage device pointed from the file information and by using the access mechanism for each external device. As the external storage devices can be treated by a file management, different file managements are not necessary to be prepared for each external storage device, and as an access becomes possible by a file management, an application is not affected even if the storage devices are changed.

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 managing storage contents by using, for example, an external storage device.

[0002]

2. Description of the Related Art FIG. 6 shows an example of a conventional file management method. In FIG. 6, 6 is a file management method A, 7 is a file management method B different from the file management method A, and 1 is a file management using an external memory. File information table 3 of method A is I / I used when accessing an external storage device.
An O mechanism, 4 is an external storage device, and 5 is a file information table in the file management system B using a disk.

7 to 9 are diagrams showing a specific example of a conventional file management system. FIG. 7 is a diagram showing a memory file management method for accessing the external memory, and is a diagram showing the file management method when the record of the file A in the external memory is read into the buffer. According to this method, when opening a file, the file name is specified and opened.

Next, FIG. 8 is a diagram showing a disk file management system in the case of accessing a magnetic disk device as an external storage device. In FIG. 8, the file is opened by designating the volume name and file name assigned to the disk. In this example, volume V1
In the example shown in FIG.

Next, FIG. 9 shows an optical disk file management system when an optical disk is accessed as an external storage device. When opening an optical disk file, first specify the device ID of the optical disk and then open it, then specify the name of the volume mounted in that device and open it, and then specify the file name in the volume name. Then, the record in the optical disk file can be accessed by opening the record.

Next, the operation of the file #L managed by the file management method A on the external memory will be described with reference to the flow chart of FIG. First, find information about file #L to access file #L. (Step A) After that, the file I / O information in the file information is taken out. (Step B) The I / O information is used to access the access mechanism to exchange data with the corresponding position. (Step C) This procedure is the same for the file management method B on the disc, but the structure and size of the file I / O information are different because the external device is different.

As shown in FIG. 7 to FIG. 9 described above, when accessing the memory file, it is sufficient to simply specify the file name. To access the disk file, specify the volume name and the file name. Further, in order to access the optical disk file, it is necessary to specify three of the device ID, the volume name and the file name.

In the program interface as described above, the method of designating the target file is different for each file access method. Also, since the file information itself such as the position and size of the file for accessing the file is on each storage medium, the file information such as the position and size of the file on each medium is stored to determine the position of the file. There was a need to have access.

[0009]

Since the conventional file management system is configured in this way, only one external storage device of the same type can be handled by one file management system, and multiple external storage devices can be handled. Required a file management method for that type. Further, since the file information itself is on each medium, each medium has to be accessed to specify the position of the file, which leads to a deterioration in performance.

The present invention has been made in order to solve the above-mentioned problems, and uses one file management system,
The purpose is to handle a plurality of different external storage devices at high speed.

[0011]

A file management system according to the present invention provides, for example, information necessary for accessing an external storage device, device information for identifying the device, and a file such as a storage position in the device. It is possible to manage a plurality of different external storage devices by dividing the information into two and managing the device information separately from the file information, and has the following elements. (A) A device information table that stores, among the access information for accessing a file, access information that differs depending on the device in which the file exists, corresponding to that device,
(B) Among the information for accessing the file, information commonly used in files placed in any device and a file information table storing the device in which the file exists corresponding to each file, (c) type File management means for providing a common interface for files existing in different devices and accessing files existing in different devices using the device information table and the file information table.

[0012]

According to the present invention, the external storage device is accessed by specifying the device by the device information pointed to by the file information and by specifying the position of the storage area by the position information in the file information. By separating the device information having device-specific information from the file information, it becomes possible to access devices of different concepts under a unified user interface.

[0013]

【Example】

Example 1. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a file #L on the external memory, a file #m on the disk, and a file #n on the optical disk library as an example. In the figure, 1 has a file attribute and definition information as file information. Among the information for accessing the file, information commonly used in files placed in any device and a pointer to the device in which the file exists A file information table 2 stored in correspondence with each file has device information for managing information of each external storage device, and among the information for accessing the file, different information depending on the device in which the file exists The device information table stored in correspondence with 3 is an I / O mechanism used when actually accessing each external storage device, and 4 is an actual external storage device.

FIG. 2 is a diagram showing a specific example of the file information table and the device information table shown in FIG. As shown in FIG. 2A, the file information table has a file name, an in-area relative address, an area ID, and file format information. For example, in file #L, the area of the file starts at a position where the relative address is 50 in the area indicated by area ID1, and the file format is the data shown in the file format information (details are not shown). Indicates that is recorded. Here, the area ID uses area IDs such as 1, 2, 3, and in this example, 1 corresponds to an external memory, 2 corresponds to a magnetic disk device, and 3 corresponds to an optical disk. It corresponds to the device. Therefore, for example, in the file #m, the area starts from the area ID 2, that is, the location where the relative address of the magnetic disk device is 90. Similarly, the file #n indicates that the area ID is 3, that is, the area starts from the position of the relative address of 200 in the area of the optical disk device.

Next, as shown in FIG. 2B, the device information table stores three items of area ID, medium type and device information. The area ID indicates the type of medium as described above, 1 is a memory device, 2 is a magnetic disk device,
Reference numeral 3 denotes an optical disk device or the like. Further, as the device information, the head address of the area and the address of the management table held in the area are stored as information for accessing the external memory. Also, as the information of the magnetic disk device, the volume name, the volume start address
The disk device ID is stored. For the optical disk device, the device ID, volume name, volume head address and slot number are stored as the information.

Next, FIG. 3 shows a concrete example of a program interface in the embodiment of the present invention.
In this access procedure, when the file is opened, only the file name is designated, and after performing a predetermined process such as reading, the process is ended by designating only the file name and closing.

Next, FIG. 4 is a diagram showing a specific example of an embodiment of the present invention. In the figure, 5 is a unified user interface that accepts the program interface as shown in FIG. Is a file management means for determining the external storage device 4 in which the file exists, preparing information necessary for opening or closing those files, and outputting the prepared information to the I / O mechanism 3.

The procedure for accessing the file #L on the external memory will be described with reference to FIGS. 1 and 4 with reference to the flow chart of FIG. First, in the program shown in FIG.
When L is specified, the file information of file #L is accessed in order to access file #L.
Find out from. (Step A) After that, the area ID in the file information is extracted. (Step B) The device information pointed to by this area ID is taken out from the device information table 2, and it is understood that the file is on the external memory for the first time. Therefore, the device information necessary for accessing the external memory is retrieved from the device information table (step C). The position information of the file information table 1 (relative address within the area) and the device information of the device information table 2 are combined to access the external memory access mechanism 3 to exchange data with the corresponding position. (Step D) When accessing the file #L on the external memory, the area start address stored in the device information table 2 and the relative address within the area stored in the file information table 1 are used to directly access the memory. Will be possible. File information table 1 and device information table 2
Can be made resident in the main memory. In this way, it becomes possible to directly access the external memory using the information in the file information table and device information table, and processing such as opening or closing is fast. It becomes possible to do it.

File #m on another external storage device,
#N can be processed by the same procedure. For example, when the file #m is accessed, the file #m is similarly designated in FIG. 3, and when the file management means 4 executes this program, first, the area ID of the file #m from the file information table 1 is specified. Search for this area ID
Find out that is 2. And device information table 2
The area ID of 2 indicates that the device is a magnetic disk device, and the volume name, the head address of the volume, and the disk device ID are extracted as the device information. Next, the magnetic disk device access mechanism 3 is accessed using the relative address in the area in the file information table, the volume name, the volume head address, and the disk device ID obtained from the device information table 2 to access the corresponding 1 data. I do. Also, file #n
3 is also present in the optical disk device in the same manner as in FIG.
It is possible to access using a common user interface as shown in.

Next, referring to FIG. 4, a method of obtaining an address and the like when accessing each external storage device will be described. When accessing the external memory, the address and size are required, but the address can be calculated from the relative address within the area of the file information table, the record length of the file format information, and the area start address of the device information table. Is. If the record length is used or the size is blocked,
The size can be obtained from the record length × block size.

Next, in FIG. 4, when accessing the magnetic disk device, the disk ID of the device information table is used as the disk ID, and the address is obtained by adding the relative address within the area of the file information table to the volume head address. be able to. Further, the size can be calculated by using the record length or the block size of blocks.

Next, in FIG. 4, in the case of the optical disk device, the device ID in the device information table can be used. For the address, the start address of the file can be obtained by adding the relative address in the area to the start address of the volume. The size can be calculated by using the record length and the block size as described above. In this way, when executing the read or write to the external storage device, it becomes possible by using only the file information table and the information in the device information table. Therefore, the file information table and the device information table are stored in the main memory. When it is placed in a high-speed storage area such as, the file access speed can be increased.

In the above description, the case of reading or writing a file has been described, but when creating a file or deleting a file, the creation and deletion are performed by using the conventional file management method. . In this embodiment, the file generation or deletion of the conventional method is used particularly for the file generation or deletion.

As described above, in this embodiment, the information necessary for specifying and accessing the external storage device, which has been included in the conventional file information, is separated from the file information and separately managed as device information. As a result, the file information is limited to the logical address information in the device and can be handled in common with each external storage device. At the time of actual access, a combination of address information in the file information and variable-length device information for each external storage device pointed to by the file information is used to access using the access mechanism for each external device.

As described above, since a plurality of types of devices can be handled by one file management means, it is not necessary to create different file management for each external storage device and one file management can be used for access. Applications are not affected even if the storage device is changed.

Example 2. Although the external memory, the disk, and the optical disk library are used as the external storage device in the above embodiment, other devices can be handled in the same manner.

Example 3. Further, even if the same type of external storage device is used, if there are a plurality of types of I / O mechanisms, it can be handled in the same way as another external storage device.

Example 4. Further, even when a multiplexed file is realized as file management, this management method can be applied as it is.

[0029]

As described above, according to the present invention, since a plurality of different external storage devices can be handled by one file management, it is not necessary to create different file management for each type of external device. Further, since the access is possible by one method, it is possible to easily deal with the change of the storage device.

[Brief description of drawings]

FIG. 1 is a diagram showing a data structure of a file management system and a flow of processing thereof according to an embodiment of the present invention.

FIG. 2 is a diagram showing a file information table and a device information table according to an embodiment of the present invention.

FIG. 3 is a diagram showing a unified access procedure according to an embodiment of the present invention.

FIG. 4 is a diagram for explaining the operation of the file management system according to the embodiment of the present invention.

FIG. 5 is a flowchart showing an access procedure according to the present invention.

FIG. 6 is a diagram showing a data structure of a conventional file management method and a processing flow thereof.

FIG. 7 is a diagram showing a conventional file management system for an external memory.

FIG. 8 is a diagram showing a file management system for a conventional magnetic disk device.

FIG. 9 is a diagram showing a file management system for a conventional optical disc device.

FIG. 10 is a flowchart showing a conventional access procedure.

[Explanation of Codes] 1 File information table 2 Device information table 3 I / O mechanism 4 External storage device 5 File information table 6 File management method A 7 File management method B 8 Unified interface 9 File management means

Claims (1)

[Claims] 1. A file management method having the following elements: (a) A device information table that stores, among the access information for accessing a file, different access information corresponding to the device in which the file exists,
(B) Among the information for accessing the file, information commonly used in files placed in any device and a file information table storing the device in which the file exists corresponding to each file, (c) type File management means for providing a common interface for files existing in different devices and accessing files existing in different devices using the device information table and the file information table.