JPH11232159A - File management method and medium storing file management program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To always keep a file on the client side and that on the server side equal to each other up to their contents. SOLUTION: Identifiers reflecting the contents of management object files are described for every files in a contents management file. A client 20 acquires the contends management file from a server 10 and compares the acquired contents management file of the server 10 with the contents management file of the client 20. Based on the comparison result between these two contents management files, the client 20 acquires required files from the server 10 and deletes unnecessary files. Files managed by the contents management file of the server 10 coincide with a designated file group stored in an HD device of the client 20.

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 keeping the contents of two files the same, and a medium storing a program for realizing file management by a computer.

[0002]

2. Description of the Related Art A conventional method of matching the contents of two files in a computer device is to compare information (file creation date, size, etc.) managed by a file system and determine whether one of the files is based on the difference. It is to determine whether or not it has been updated. However, since the information managed by the file system is separate from the contents of the file, the management information may be the same even if the contents of the two files are different, which is not always sufficient. .

[0003] There is also a method in which, when one file is updated, the updated file is copied after deleting all of the other file. However, this method is not practical because it overloads the system and increases the time required for processing.

[0004]

DISCLOSURE OF THE INVENTION The present invention provides a file management method that can relatively easily and surely maintain the identity of two files.

[0005] The file management method according to the present invention comprises:
A file management method for making a content of a second file identical to a content of a first file in a system including a second file and a second file whose content is to be kept the same as the first file. ,
A first file identifier is generated based on the contents of the first file, first file management information including at least the first file identifier is created, and when the first file is updated, The first file management information including the first file identifier is updated by the first file management information including the second file identifier for the second file. Comparing the second file with the first file, when the second identifier is different from the first identifier, updating the second file according to the update of the first file, and updating the second file management information to the first file.
Is updated in accordance with the update of the file management information.

[0006] Most commonly, the first file is stored on a first storage device and the second file is stored on a second storage device different from the first storage device. In this case, the first storage device generally forms part of or is used in the first computer,
The second storage device is a part of the second computer different from the first computer or is used in the second computer. The first computer and the second computer are connected by a network or a system bus (or line). The first and second storage devices are a semiconductor memory, a magnetic storage device, a magneto-optical storage device,
This is realized by an optical storage device or the like.

In the above system, the first file management information and a program for creating or updating the first file management information (file management information creation program) are stored in the first computer. 2
File management information and a program (file update program) for comparing the file management information, updating the second file, and updating the second management information are the second file.
Will be stored in your computer. The first file management information is transferred from the first computer to the second computer for comparison of the file management information and for updating the second file management information. First file management information is obtained through a bus or the like). A first file required for updating the second file is transferred from the first computer to the second computer, or read from a portable recording medium (FD, CD-ROM, etc.) into the second computer. (Transferred).

The first file management information and the file management information creating program may be provided in a third computer connected to the first computer. Similarly, the second file management information and the file update program may be provided on a fourth computer connected to the second computer.

The first computer and the second computer do not have to be connected by a network, a bus or the like.
In this case, the first file management information and the first file will be transferred from the first computer to the second computer using a portable recording medium (for example, FD, CD-ROM).

[0010] The first computer and the second computer may be the same. The first storage device and the second storage device may be the same. In these cases, the second file will generally be for backup of the first file.

The first file generally includes a plurality of files. Similarly, the second file generally includes a plurality of files. A file identifier is created for each file. The file is a concept including an execution program file, a data file, and the like.

A file identifier uniquely represents the content of a file, and is calculated using the file content according to various algorithms.

The file management information may include a file name, a version number, and other data (such as directory information) in addition to the file identifier.

Updating a file includes changing the contents of the file, adding a file, deleting a file, and the like.
Therefore, in the comparison between the corresponding first file identifier and the second file identifier, one may not exist. Updating the file management information includes changing, adding or deleting a file identifier.

It is assumed that the first file and the second file are the same including the content at the start of the file management operation. Further, the same file management information as the first file management information is prepared as the second file management information.

The comparison between the first file management information and the second file management information may be performed at system startup, periodically, or in response to an input from a user.

The present invention also provides a recording medium storing a file management program for controlling a computer in order to realize the above-described file management method by the computer. File management programs can be broadly divided into file management information creation programs and file update programs. These file management information creation program and file update program may be stored in separate recording media. The program recording medium includes a semiconductor memory, a magnetic storage device (FD, hard disk, etc.), a magneto-optical storage device, and an optical storage device (CD-ROM, etc.).
The file management program, the file management information creation program, and the file update program can be provided by themselves, or as a part of an application program, a system program, or the like, as a part of the OS, or as a utility.

According to the present invention, the file identifier calculated using the contents of the file is used for comparing the file contents. Since the file identifier reflects the file content, it is unique (unique) to the file, and can maintain extremely high uniqueness. Therefore, the difference between the contents of the two files can be determined very accurately. Since the data length of the file identifier can be much shorter than that of the file contents, it can be transmitted and compared in a short time, and the system load is small and the required time is short. short. Since the file content is updated only for files having different file identifiers, the load can be reduced and the processing time can be reduced from this point as well.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment The first embodiment relates to file management in a system in which a plurality of computers constitute a network. One of the plurality of computers is a server, and the other computer is a client. One or more identical files to be managed (including program files, data files, and other files)
In principle, it is assumed that the server exists on both the server and the client.
If the R and the content management file exist, it is sufficient for file management, and in exceptional cases, it is permissible that the file does not exist on the server.) When a server adds or deletes a file or changes a file content (content), the client easily detects the change, and the client similarly adds or deletes a file or changes the content. The files on all clients connected via the network are identified with the files managed by the server. The load on the server and the load on the client are reduced, and the processing time (including the time required for file transfer) is reduced.

(1) Configuration of Network System FIG. 1 shows the overall configuration of the network system.
Shows a hardware configuration of a server constituting the system.

A server computer 10 (hereinafter referred to as a server) and one or more client computers
20 (hereinafter referred to as clients) are communicably connected via a network. The network includes all circuits capable of data transmission, such as a public line network, a dedicated line network, and a LAN (Local Area Network) (including operation using the Internet, WAN (Wide Area Network), Ethernet, and the like).

The server 10 includes a central processing unit (CPU) 13. An input device 11 (keyboard, mouse, etc.) for receiving input, an output device 12 (CRT display device, printing device, etc.) for visually outputting data, and a CPU 13 are connected to the CPU 13 via a bus. Communication equipment
14. Internal memory 15, which provides a program area for storing programs, a work area for various operations, a buffer area, etc., reads data recorded on a floppy disk (FD), and records data on the FD FD drive 16, CD-ROM drive 17 for reading data recorded on CD-ROM 19, and hard disk (HD) storing an operating system and the like
Device 18 is connected.

The client 20 has basically the same hardware configuration as the server 10. In FIG. 2, the client 20
Is indicated by reference numerals in parentheses.

The HD device 18 of the server 10 stores the following in terms of file management. (i) Master directory (hereinafter referred to as master DIR) (ii) Files to be managed (iii) Content management file creation program (iv) Content management file

The following are stored in the HD device 28 of the client 20 in terms of file management. (xi) Slave directory (hereinafter, slave DIR)
(Xii) Specified file group (xiii) Update processing program (xiv) Initial setting file (xv) Content management file

(2) Master DIR, slave DIR, content management file, etc. Files used by all clients 20 (particularly constituting a specific group) connected to the network are always the same, including their contents. Keeping things is the purpose of file management. Server 10
When there is an addition or deletion of a file or a change in the content of a file, the client 20 promptly also adds or deletes a file or changes the content of the file.

The target of such file management is as follows:
Alternatively, a file desired to be targeted is determined by a user (administrator). In general, the information (eg, file name, size, creation date) of multiple (or many) files that are determined to be subject to file management (this is the group of files to be managed in (ii) above) and The information regarding the content management file of (iv) is described in the master DIR of (i). The "master" of the master DIR in the server 10 and the "slave" of the slave DIR in the client 20 are used herein as terms that correspond to each other. The master DIR is a directory created from the viewpoint of file management described in this specification. The master DIR is most generally completed when a group of files to be managed is installed in the HD device 18 of the server 10 and stored in the HD device 18. However, the master DIR can be created in another computer system and copied to the HD device 18 of the server 10.

FIG. 3 shows an example of the contents of the master DIR. The master DIR has lower directories (A_DIR, B_DIR, C_DIR, F_DIR, D_DI) hierarchically arranged in a tree structure.
R, E_DIR) and various files m1.ex
e, m1.dat, etc., and directory information of the content management file X. The lower directories describe the lower directories (for example, the directories managed by C_DIR are D_DIR and E_DIR) and directory information such as various files a1.exe, a2.exe, a1.dat, and a2.dat including. Here, exe indicates an execution (program) file, and dat indicates a data file. In the master DIR, a user (server administrator) stores directory information relating to files (for example, history files, log files, etc.) other than the files to be managed for the convenience of the user or for the convenience of the user. There is also.

The (iv) content management file X is for performing file management up to the content of the management target file. This content management file X
When creating a file, select (or confirm) the files to be managed for more reliable and more efficient file management.
And grouping are performed.

The file to be managed is basically distributed to the client 20 (using a recording medium such as an FD or a CD-ROM,
Or by transfer) and used or used in the client 20. The file in which the directory information is described in the master DIR is a file determined from the viewpoint of the management target as described above. On the other hand, the file in which the content information (described in detail later) is described in the content management file X has been determined, specified, selected, or confirmed from the viewpoint of being used or used in the client 20. Master D
The file managed by the IR and the file managed by the content management file X generally match, but may not match.

As described above, the directory information of files other than the file to be managed may be described in the master DIR for the convenience of the user. In order to exclude such files other than the management target file, a file to be registered in the content management file X is selected or confirmed.

In a more positive sense, selection or confirmation of a file to be registered in the content management file is useful in the following file management system. The plurality of clients 20 connected to the network are divided into two groups, and independent file management is performed for each group. The master DIR stores directory information of managed files used by all clients in both groups. A content management file is provided for each group, and content information of files used in the corresponding group is stored in each content management file. The master DIR can be commonly used by two groups of file management systems.

In any case, since the content management file X is important for managing the contents of the file, the file registered therein is the master D
It is meaningful that the IR data is not simply copied but confirmed by the user.

Today, programs are subdivided, dedicated, unitized or singulated. All the tasks of one application are hardly performed by one program, and generally one application is realized by a set (or combination) of a plurality of program files. In that sense, it is preferable to group the files for each application or for each unit for efficiently managing a plurality of files. This is particularly desirable from the viewpoint of performing version upgrade in units of one group. Each group thus grouped is called an application group.

FIG. 4 shows a state in which files selected (or confirmed) as files to be registered in the content management file X among the files to be managed described in the master DIR are grouped. The entirety of the files selected or confirmed to be registered in the content management file X is called an “application system”.
The application system is composed of a plurality of application groups. Each application
Generally, a plurality of files belong to a group.

FIG. 5 shows an example of the content of the content management file X.

There is a description relating to the application system “System”. The application system has a version number (Ver = 2.00) and a start date of use of the system with this version number (hereinafter referred to as “use start date”) (St
art-date = 1997/12/19).

The application group "Applicatio
ns ". This description includes, for each application group (APPL_GROUP1, APPL_GROUP2), these version numbers (1.00, 2.00) and the expiration date of the group of those version numbers (hereinafter referred to as the expiration date) (1997/1997). 12/31, 1998/01/15).

For each application group, there is a description about the files contained therein. The description about this file includes the master DIR to which the file belongs.
It contains information on directory names, file names, and identifiers in the directory. For example, the first of "APPL_GROUP1"
"A_DIR" on the line is the application group "APP"
The directory that manages one of the files belonging to "L_GROUP1" is named "A_DIR", "a1.exe" indicates that the file is named "a1.exe", and 350889145,69 are It represents the file identifier and file size created for the file with the file name "a1.exe". 350889145 is the file identifier and 69 is the file size. The file identifier is a specific operation (for example, CRC (Cyclic Redundancy Check) using all (or a part of) data included in the file.
)). Therefore, the file identifier may be considered as a kind of compressed data representing the content of the file itself, and is unique to the content of the file. It is determined whether or not the content of the file has been changed based on the file identifier. Information described in such a content management file, particularly a file identifier, is called content information.

The content management file X of (iv) of the server 10 is created in the server 10 according to the content management file creation program of (iii).
The (xv) content management file of the client 20 is
In starting up (initial setting) the operation of the file management system, the content management file created in the server 10 is copied (through a recording medium or transfer) and thereafter updated in the client 20. The content management file creation program of (iv) is a CD-ROM 19
(Or FD) is recorded on the HD of the server 10
Installed on device 18.

The file group selected or confirmed to be registered in the content management file X is described in (xii) above.
This is called a specified file group. In the server 10, the group of files to be managed is installed from the CD-ROM or FD in the HD device 18 (some files may not be installed). In the client 20, the specified files are installed from the CD-ROM or FD to the HD device 28 (they may be transferred from the server 10). When the file management system is started (at the time of setting), it is assumed that the specified file group stored in the HD device 28 of the client 20 matches the file group registered in the content management file X. .

The (xi) slave DIR is a client
The directory information describes a specified file group stored in the HD device 28. The file name of the directory information is created in the server 10 by referring to the content management file X based on the master DIR. You. The slave DIR is copied to the HD device 28 of the client 20 (through a recording medium or transfer), and is completed when the client 20 installs the designated file group in the HD device 28 (or when transferred from the server 10). A slave DIR can also be created at the client 20. Slave DIR
Is also used for file management. If the managed file group and the specified file group are the same, basically (file name etc. in directory information)
The master DIR data and the slave DIR data will be the same.

As described above, at the start of the operation of the file management system, each file of the specified file group stored in the HD device 28 of the client 20 is managed by the content management file X of the server 10 up to its contents. File is exactly the same. When the server 10 adds or deletes a file managed by the content management file X or changes the file content, the client 10
The 20 designated file groups no longer match the file group managed by the content management file X.

The update processing program (xiii) determines whether or not the specified file group stored in the HD device 28 of the client 20 and the file group registered in the content management file X of the server 10 match. Is checked not only for the presence / absence of the file but also for the contents of the file. If the contents do not match, a necessary file is obtained from the server 10 or an unnecessary file is deleted from the HD device 28, so that This is a program for matching a specified file group stored in the HD device 28 with a file group managed by the content management file X of the server 10.

The (xiv) initialization file contains the server 10
Address on the network, the path to the content management file X stored in the HD device 18 of the server 10, the address of the client 20 on the network,
The path to the content management file stored in the HD device 28 and the destination address of a communication result log described later are described. The initial setting file recorded on the CD-ROM 29 (or FD) together with the update processing program is installed in the HD device 28 of the client 20.

(3) Creation and Update of Content Management File in Server The content management file X is newly created when the operation of the file management system is started (initial setting). The content management file X is updated when a file is added or deleted or the content of the file is changed in the application system. FIG. 7 shows the procedure of the processing for creating and updating the content management file X according to the content management file creation program.

When the content management file creation program is started, a menu instructing "creation" or "update" of the content management file X is displayed on the output device (C).
(RT display device) 12 is displayed on the display screen. When the user selects "create" of the content management file X (created in step 103), a list of files managed by the master DIR is displayed. The user selects (or confirms) files to be registered in the content management file X from the files managed by the master DIR, and groups them on the display screen. Input attribute information (version number, use start date) of the application system including all selected files and attribute information (group name, version number, expiration date) of each application group using the input device 11 ( Steps 104 and 105).

When the selection (designation) of the files with the setting of the attribute information and the grouping is completed and the save is instructed, the file identifier is transmitted to the content management file creating program using the contents of each of the selected files. Therefore, it is automatically calculated (step 106). A content management file X as shown in FIG. 5 is created using the input attribute information, the calculated file identifier, and the like, and is stored (saved) in the HD device 18 (step 107).

The content management file created in the server 10 is passed to the client 20 (through a recording medium or transfer) and stored (saved) in the HD device 28. When starting operation of the file management system, the server
The ten content management files X and the content management file of the client 20 are exactly the same.

In the server 10, the user adds a file to the application system or changes the content of a file included in the application system (eg, rewrites a file stored in the HD device 18).
It can be performed. In such a case, the master DI
This involves updating of R. As shown in FIG.
When the updating of the content is completed (step 101), the user starts the content management file creation program (step 101).
102). When deleting a file included in the application system, the user activates the content management file creation program without updating the master DIR (of course, the directory information of the file to be deleted may be deleted).

The user selects "update" in the process (FIG. 7) according to the content management file creation program ("update" in step 103). server
The content management file X stored in the ten HD devices 18 is read (step 108), and the files belonging to the application system managed by the content management file X and the attribute information are displayed.
When adding a file, the user selects (designates) the file to be added (the master DIR is also displayed so that the user can select a file from the file) to belong to any application group. )
I do. When deleting a file, the user instructs to delete the file from the content management file X (step 109).

In either case of adding or deleting a file or changing a file content, in this embodiment, the user is required to enter the application / file to which the added file belongs.
Change the version number of the group, the application group to which the deleted file belongs, or the application group to which the file whose contents have changed. Further, the version number of the application system is changed (step 110).

Thereafter, for each of the files (selected files) included in the application system, a file identifier is calculated again using the file contents (step 106). File identifiers may be calculated only for files that have been added or whose contents have been changed. HD device 18 of server 10
Stores the content management file X including the newly calculated file identifier and the like (step 107).

The calculation of the file identifier is always performed according to the same algorithm. Therefore, the file identifier of the file whose content has been changed is different from the file identifier before the content is changed. Of course, the file identifier of a file whose content has not changed does not change. For newly added files,
A file identifier reflecting the content of the file is generated together with the file name and the like, and registered in the content management file X. Data about the deleted file no longer exists in the content management file X.

When updating the content management file, an application group can be added or deleted. The newly added file may belong to the newly added application group. When the application group is deleted, data on all files belonging to the group is deleted from the content management file X.

(4) Update Process of Specified File Group at Client The specified file group is distributed to the client 20 and installed in the HD device 28 of the client 20 as described above. When a file is added, deleted, or changed in file content in the server 10, the content management file X is updated as described above. server
The addition, deletion, and change of contents of the file in 10 must be reflected also in the specified file group stored in the HD device 28 of the client 20. In the client 20, using the updated content management file X of the server 10, a process of adding or deleting a file or changing a file content in the same manner as in the server 10 is called a specified file group update process. FIG. 8 is a flowchart showing a processing procedure of the update processing program stored in the HD device 28 of the client 20.

The update processing program is started, for example, when a user of the client 20 inputs a start instruction of the update processing program from the input device 21.
It may be set to start automatically at a predetermined time (for example, midnight), or may be started by a user or another program. When the power of the client 20 is turned on, the client 20 may be started automatically, or may be started by a user or another program. It may be activated every time a fixed time elapses, or may be activated. In any case, the update processing program is started in the client 20 at a predetermined time, periodically, or as needed.

First, based on the address of the server 10 on the network and the path to the content management file X described in the initialization file, the client 20 copies the content management file X stored in the HD device 18 of the server 10. Is obtained (step 201). The content management file X obtained from the server 10 is stored in the internal memory 25 of the client 20.

The content management file stored in the HD device 28 of the client 20 is also transferred to its internal memory 25. The two content management files are compared.

First, the version number of the application system (hereinafter, referred to as system Ver) described in each of the two content management files is compared (step 202). If the system Vers are different (NO in step 202), the server 10 adds a file to the application system, deletes a file from the application system, or changes a file content of a file included in the application system. Means that it was done. Here, the file addition includes a case where a new file is added to an existing application group and a case where an application group is generated based on a file to be added (addition of an application group). Files can be deleted by deleting files from the existing application group or by deleting all files belonging to the existing application group.
There is a case where each group is deleted (deletion of an application group). The content management file contains descriptions about the application group (group name,
Version number, expiration date), it is possible to determine whether an application group has been added or deleted based on this description. Whenever a file is added, deleted, or its contents changed, the version number of the application group to which the file belongs is changed, so the file is added, deleted, or its contents changed. Can identify the application group in which the error occurred. Therefore, application groups are compared in the two content management files (step 203).

If there is no description about the application group in the content management file X of the server 10 in the content management file of the client 20, it is determined that the application group is a group added in the server 10. Step 203; Add Group). The client 20 acquires all files belonging to the application group added in the server 10 from the server 10 (step 204).

The client 20 accesses the HD device 18 of the server 10 to obtain a copy of a file through a network, or obtains an FD or C
It can be obtained by reading a file from the D-ROM. File from client 20 to server 10
The request may be sent, and the server 10 may transmit the file to the client 20 via the network.

Conversely, if the description of the application group in the content management file of the client 20 is not in the content management file X of the server 10, it is determined that the application group is a group deleted in the server 10. (Step 20
3; delete group). The client 20 copies all files belonging to the group deleted on the server 10 to H
It is deleted from the D device 28 (step 205).

Although the description about the application group described in the content management file X of the server 10 exists in the content management file of the client 20,
But the version number of those groups (Group Ve
r) are different from each other, it is determined that the server 10 has added or deleted a file belonging to the group or changed the file content (step 203; change the group Ver). The difference analysis using the file identifier is performed for all the files belonging to the application group (step 206).
).

For all the file identifiers included in the content management file of the client 20, differences between them and the file identifiers included in the content management file X of the server 10 are calculated one by one. If a file identifier having the same value exists in both content management files, it means that the file with the file identifier has not been added, deleted, or changed in the file content in the server 10.

The fact that the same file identifier in the content management file of the client 20 does not exist in the content management file X of the server 10 means that the file corresponding to the file identifier has been deleted in the server 10 or the file content Has either been changed. The fact that the same file identifier in the content management file X of the server 10 does not exist in the content management file of the client 20 means that a file corresponding to the file identifier has been added in the server 10 or the file content has been changed. Either one.

In such a case, the same file as the file of the server 10 is secured in the client 20 as follows. That is, the client 20 acquires from the server 10 a file corresponding to the file identifier included only in the content management file X of the server 10. Further, the client 20 deletes a file corresponding to the file identifier included only in the content management file of the client 20 from the HD device 28. The file managed by the content management file X of the server 10 and the specified file group stored in the HD device 28 of the client 20 are the same up to the content.

In the above processing, the server of the file that does not exist in the client 20 is determined based on only the file identifier.
Acquisition from server 10 and client 20 but server 10
Client 20 for files no longer managed
Has been removed. Since the file identifier reflects the content of the file, any slight change in the content will result in a different file identifier. File contents of server 10 and client
Identification with the contents of 20 files can be achieved.

The addition or deletion of a file may be determined using the file name (assuming that the file name is not changed when the file content is changed). That is, the file names of the content management file of the client 20 and the content management file X of the server 10 are compared with each other. If the file exists in the content management file X of the server 10 and does not exist in the content management file of the client 20, it is determined to be added.
It is determined that a file not included in the ten content management files X is deleted. If the same file name exists in both content management files, the process proceeds to the comparison of the file identifier. If the file identifiers are the same, it is determined that the file contents have not changed.
It is determined that the content has been changed.

After the file is acquired or deleted, the content management file acquired from the server 10 is stored in the HD device 28 of the client 20 instead of the content management file stored in the HD device 28 of the client 20. (Step 208). Finally, a communication result log that records the success or failure of the file acquisition is created and transmitted to the transfer destination address (generally, the server 10) described in the initialization file (step 209).
), All processing of the update processing program ends.

If the system Ver described in the content management file of the server 10 matches the system Ver described in the content management file of the client 20 (YES in step 202), the HD of the client 20
The specified file group stored in the device 28 is exactly the same as the file managed by the content management file X of the server 10 up to the content. The update processing program terminates without performing any processing.

FIG. 9 shows the progress of the updating process performed in the client 20 when a file is added or deleted in the server 10. The updating process proceeds in the order of upper, middle, and lower stages.

In the upper part of FIG. 9, the files belonging to the application system in the server 10 and the designated file group stored in the HD device 28 of the client 20 are:
All are a file, b file, c file and d file. The server 10 and the client 20 have a content management file X in which the same content information is described.

In the middle part of FIG. 9, the server 10 deletes the d file from the application system and newly adds the e file. The server 10 updates the content management file. A content management file in which new content information is described is denoted by a symbol Y. The client 20 acquires the content management file Y from the server 10 and compares it with the content management file X of the client 20. As a result of the comparison, the client 20 acquires the e-file from the server 10 and
Delete file d from 28. The file included in the application system of the server 10 (the file managed by the content management file Y) and the specified file group stored in the HD device 28 of the client 20 become the same up to the content. (Lower part of FIG. 9).

Second Embodiment FIG. 10 shows the overall configuration of a system according to a second embodiment. The server 10 and the client 20 are not connected via a network. Other points are the same as the first embodiment.

In the server 10, a file is added, deleted, or a file content is changed, and the content management file X of the server 10 is updated accordingly.
The content management file X and the management target file group updated in this way are recorded (copied) on the FD in the server 10 and the FD is transferred to the client 20 side.
The user of the client 20 sets this FD in the FD drive 26. The update processing program is started. The content management file X of the server 10 is read from the FD,
This is compared with the content management file of the client 20. In accordance with the result of the comparison, a necessary file is read from the FD, stored in the HD device 28 of the client 20, and an unnecessary file in the HD device 28 of the client 20 is deleted. The content management file of the client 20 is updated by the content management file X in the FD. In this way, the file of the client 20 is made the same as the file of the server 10 up to its contents offline using the FD.

Third Embodiment FIG. 11 shows the overall configuration of a network system according to a third embodiment. A content management file creation computer 10B and an update processing computer 20B are connected to the network in addition to the server 10A and the client 20A. The hardware configurations of the server 10A, the client 20A, the content management file creation computer 10B, and the update processing computer 20B are basically the same as those shown in FIG.

The HD device of the server 10A has a master DIR,
A management target file group and a content management file are stored. The HD device of the client 20A stores a slave DIR, a specified file group, and a content management file. The content management file creation program is a content management file creation computer 10B
The update processing program and the initialization file are stored in the HD device of the update processing computer 20B.

The content management file creation computer 10B having the content management file creation program
Necessary data such as a master DIR is acquired from the server 10A, and a content management file X is created. This content management file X is stored in the HD device of the server 10A.

When a file is added or deleted or a file content is changed in the server 10A, the content management file creation computer 10B obtains data representing these from the server 10A and updates the content management file X. I do. The updated content management file X is returned to the server 10A.

The update processing computer 20B is a client
Acquires the content management file from 10A, server 10A
Obtains the content management file X from. Update processing computer according to comparison of both content management files
20B obtains necessary files from server 10A, passes them to client 20A, and deletes unnecessary files in client 20A.

As described above, the content management file creation program and the update processing program are stored in a device different from the server and the client, respectively, and the content management file creation program and the update processing program are executed in a device different from the server and the client. By adopting the configuration, a flexible network system can be configured.

Fourth Embodiment FIG. 12 shows a system configuration of a file management system according to a fourth embodiment. In the configuration shown in FIG. 12, the one stored in the HD device 18 of the server 10 of the first embodiment (the above (( i) the master DIR, the above (ii) group of files to be managed, the above (iii) the content management file creation program and the above (iv) content management file), and the one stored in the HD device 28 of the client 20 (the backup DIR (first (Same as (xi) slave DIR in one embodiment), (xii) specified file group, (xiii) update processing program, (xiv) initialization file, and (xiv)
(xv) content management file). The (xii) designated file group is generally used for backup.

When a file is added or deleted or a file content is changed in the file group to be managed,
Using the content management file, the files of the specified file group for backup are similarly added, deleted, or the file content is changed. A specified backup file group that is always the same as the used file group is secured.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an overall configuration of a network system according to a first embodiment.

FIG. 2 is a block diagram illustrating a hardware configuration of a server.

FIG. 3 shows the contents of a master DIR.

FIG. 4 shows a state in which files selected to be registered in the content management file X are grouped.

FIG. 5 shows the contents of a content management file X.

FIG. 6 is a flowchart showing a process of the server in a process of updating a master DIR in the server.

FIG. 7 is a flowchart illustrating a processing procedure of a content management file creation program in a server.

FIG. 8 is a flowchart illustrating a processing procedure of an update processing program.

FIG. 9 shows a state of progress of an update process in a client when a file is added and deleted in the server.

FIG. 10 shows an overall configuration of a system according to a second embodiment.

FIG. 11 shows an overall configuration of a network system in a third embodiment.

FIG. 12 shows an overall configuration of a system according to a fourth embodiment.

[Explanation of symbols]

 10 Server computer 20 Client computer 11, 21 Input device 12, 22 Output device 13, 23 CPU 14, 24 Communication device 15, 25 Internal memory 16, 26 FD drive 17, 27 CD-ROM drive 18, 28 HD device 19 , 29 CD-ROM

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Mitsuru Shiratori 16th Ichibancho, Chiyoda-ku, Tokyo Inside the Japan Research Institute, Inc. (72) Inventor Hiroshi Ikeda 16th Ichibancho, Chiyoda-ku, Tokyo Japan Comprehensive Research Inc. (72) Inventor Kiyoshi Kurita 16th Ichibancho, Chiyoda-ku, Tokyo Inside Japan Research Institute, Inc. (72) Inventor Yoshikazu Yukigata 16th Ichibancho, Chiyoda-ku, Tokyo Inside Japan Research Institute, Inc.

Claims (4)

[Claims] 1. In a system including a first file and a second file whose contents are to be kept the same as the first file, the contents of the second file are identified with the contents of the first file. Generating a first file identifier based on the contents of the first file, creating first file management information including at least the first file identifier,
When the first file is updated, the first file management information including the first file identifier is updated accordingly, and the second file management information including the second file identifier for the second file is updated. Is compared with the first file management information including the first file identifier, and when the second identifier is different from the first identifier, the second file is updated according to the update of the first file. And updating the second file management information in accordance with the update of the first file management information. 2. In a system including a first file and a second file whose contents are to be kept identical to the first file, the contents of the second file are identified with the contents of the first file. Storing a program for causing a computer in the system to execute file management for generating a first file identifier based on the content of the first file, and at least the first file identifier. The first file management information including the first file identifier is created, and when the first file is updated, the first file management information including the first file identifier is updated accordingly. The second file management information including the second file identifier is compared with the first file management information including the first file identifier. , When the second identifier is different from the first identifier, the second file is updated according to the update of the first file, and the second file management information is updated to the first file management information. A medium that stores a program for file management that controls a computer to update it according to the requirements. 3. A file identifier is created based on the contents of the file, file management information including at least the file identifier is created, and when the file is updated, the file management information including the file identifier is updated accordingly. That stores a file management information creation program for controlling a computer to execute the program. 4. A first file including a first file identifier generated or updated based on the content of the first file.
And compares the second file management information including the second file identifier for the second file with the first file management information including the first file identifier. When it is different from the first identifier, a command to update the second file according to the update of the first file is issued, and the second file management information is updated according to the update of the first file management information. A medium storing a file update program for controlling a computer to execute.