JPH03256145A - Duplexed file system - Google Patents

Abstract

PURPOSE:To make it possible to input updating data in copying and to attain the complete coincidence of the contents of two files by temporarily storing the contents of the updating data into a buffer, and after the completion of copying processing, writing the updating data into both the files. CONSTITUTION:It is supposed that the updating data of an already copied area are inputted to a CPU 5a during the data copying processing from a file Fa to a file Fb. In this case, the updating data are temporarily stored in the buffer Ba, and after the completion of the copying processing, the updating data stored in the buffer Ba are written in the prescribed areas of the files Fa, Fb. When the updating data of uncopied area are inputted, the input data are directly writted in a prescribed area of the file Fa. Thereby, the contents of data stored in both the files Fa, Fb can be made to always coincide with each other in any case of inputting updating data to the copied area or the uncopied area.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a duplex system used in a data processing device and provided with two files in which data of the same content is stored.

(bl) Conventional technology When an external storage device such as a hard disk is connected to a data processing device, files formed on the external storage device are always exposed to the risk of being destroyed due to physical causes or erroneous operations. Therefore, in conventional data processing devices, two files with the same content are created in different storage devices, and if one of the files is destroyed, the cause of the destruction is removed, and then the undamaged file is restored. Some devices are equipped with a redundant file system that copies normal files to the storage device after recovery.By duplicating files in this way, the security of the data to be stored is improved. There is.

(C1 Problem to be Solved by the Invention) However, in the conventional duplex file system, during the process of copying a file from one storage device to another, a new file is transferred to the copy source file via a data terminal, etc. If updated data is input that corresponds to an area for which copy processing has already been completed, the updated data will be rewritten only in the copy source file, and will not be added to the copy destination file. The update data was configured so that it could not be rewritten.Therefore, after the copying process was completed, there would be a difference between some of the two files, making it impossible to perform accurate data processing. In order to prevent file mismatches, there is no choice but to not accept input of update data during copy processing, which poses a problem that hinders the operation of the data processing device.The purpose of this invention is to During the data copying process, if update data is input for an area for which the copying process has already been completed, the contents of this updated data are temporarily held in the sofa, and then stored in the buffer after the copying process is completely completed. A redundant file system is provided that writes the retained update data to both files, enables input of the update data during the copying process, and prevents discrepancies in the data stored in both files. It is about providing.

(Means for Solving Problem d1) The duplex file system of the present invention is a duplex file system that includes two files storing data of the same content, from one copy source file to the other copy destination file. data holding means for holding updated data for areas for which copy processing has already been completed during copy processing to the file; and update data writing for writing the updated data held by the data holding means into both files after file copy processing is completed. It is characterized by providing means.

(81 Effect) In this invention, when update data for an area for which copying processing has already been completed is input during file copying processing, the updated data is temporarily held by the data holding means,
After the copy process is completed, the updated data held is written to both files. Therefore, the update data accepted during the copying process is not written to only one file, and the contents of the two files completely match.

(f) Embodiment FIG. 1 is a diagram showing the configuration of a duplex file system that is an embodiment of the present invention.

The terminal l used for performing data processing is connected via transmission line 2 to two file processing units 3.4, terminals ≧1 accessing file processing units 3.4 via transmission line 2. . File unit 3.4 has the same configuration, files Fa,
Fb, buffers Ba and Bb that temporarily hold updated data, and a CPU 5 a that manages input and output of data to these buffers.
.

5b. CPUs 5a and 5b process files Fa and F according to instructions input from terminal 1.
Execute human output of data for b. Also, when a file copy processing command is manually issued from terminal l, the CPU
5a and 5b transfer data from one file to the other file and execute file copy processing. This file copy processing command consists of a start address, data length, and direct transfer processing command.

FIG. 2 is a flowchart showing the processing procedure of the file processing unit that constitutes the duplex file system.

During the file copy process of copying a file from one copy source file processing unit 3 to the other copy destination file processing unit 4, the CPU 5a of the copy source file processing unit 3 determines whether update data has been manually input at the terminal 1. (nl), and if there is no updated data, transfer a predetermined amount of data in the file Fa to the file Fb of the copy destination file processing unit 4 until the copying process is completed (n 1 → n 5. n 6 →n
1).

If there is updated data, it is determined whether the area has already been copied (n2), and if the updated data is for an area for which the copying process has not yet been completed, it is stored in a predetermined area of file Fa. Write update data (n
2→n3). If the updated data is for an area for which copy processing has already been completed, it is held in buffer Ba (n2
→n4). As described above, the CPU 5a transfers data from the file Fa to the file Fb during the file copy process, and when update data is manually input during this time, it is stored in the file Fa or transferred to the file depending on the area corresponding to the data. After the copy process is completed, it is determined whether there is updated data in the buffer Ba (n7), and if the updated data is held in the buffer Ba, the updated data is stored in both files Fa and Fb. (n8, n9).

In the above processing, nl, n2. n4 is buffer Ba,
It corresponds to the data holding means of this invention together with Bb, and n7
.about.n9 also corresponds to update data writing means.

As described above, during the data copying process from file Fa to file Fb, as shown in FIG.
bl) is input, it is temporarily held in the buffer Ba, and after the copying process is completed, the update data D1 held in the buffer Ba is transferred to the file Fa.
and write in a predetermined area of Fb. On the other hand, when update data D2 for area fa2 (Fb2) for which the copying process has not yet been completed is input, it is written as is in a predetermined area of file Fa. This allows the contents of the data stored in the two files to always match even when update data is manually input to an area where copy processing has already been completed or an area where copy processing has not yet been completed. I can do it.

During the copy process of copying a file from file Fb of file processing unit 4 to file Fa of file processing unit 3, CPU 5b selects buffer Bb or file F depending on the area to which updated data is to be written.
Write in either b. Furthermore, in this embodiment, a case has been described in which a file processing unit is connected to the outside of the terminal via a transmission line, but the present invention can be applied to a system having duplicated files in the same device. It can be implemented. In this case, a single file is sufficient. Also, each of the files has a C
There is no need to provide a PU, and the human output of data to the two files may be controlled by the control unit of the device (terminal).

(g) Effect of the Invention According to this invention, when update data is manually input to an area where copy processing has already been completed during file copy processing, the updated data is temporarily held in the data holding means, and the copy processing After the update data is completed, the updated data is written to a predetermined area of both files. Therefore, even if update data is input during copy processing, there will be no discrepancy between parts of the two files, and data processing operations can always be performed accurately.

A flowchart showing the processing procedure of the control unit, Figure 3 is the same as 2.
3, 4 - File processing unit; Ba, Bb - buffer Fa, Fb - file; DI, D2 - update data.

Claims (1)

[Claims] (1) In a duplex file system with two files that store data of the same content, update data for an area where copy processing has already been completed during copy processing from one copy source file to the other copy destination file What is claimed is: 1. A duplex file system comprising: a data holding means for holding data; and an update data writing means for writing update data held by said data holding means into both files after copy processing is completed.