JPH11120044A - Data processing device, data processing method, data processing system, and recording medium - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To prevent the reference relationship of other data from being affected even if data having a reference relationship with other data is deleted. SOLUTION: A CPU reads a header portion (512 bytes) of a file to be erased from a flash memory and stores it in a RAM. Then, the "number of links" in the OS header is reduced by one, and further, in the directory to which the file to be deleted belongs, the directory entry relating to the file to be deleted is entered from the system entry area of the directory file. Is deleted (step S1). The CPU
It is determined whether the new “number of links” is zero, and when it is determined that the number has become zero, this file is deleted (step S
3) If it is determined that the number is not zero, the OS header is updated to a new "number of links" (step S4).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data processing apparatus for managing data recorded on a recording medium.

[0002]

2. Description of the Related Art Data stored in a recording medium such as an optical disk, a magnetic disk, and a flash memory is read from a recording medium by a host computer, for example, to manage the data, thereby constructing a hierarchical directory structure. By being managed. Further, the data recorded on the recording medium includes not only information for constructing a directory structure but also information indicating data of a reference destination. This allows the host computer to not only manage the data in a directory structure,
It is also possible to manage by recognizing the reference relationship between data and data.

[0003]

However, when the host computer reads the data having the reference information from the recording medium, it is difficult to process the data without causing a problem in the reference relation.

For example, if data is deleted irrespective of the presence or absence of a reference relationship, the data that referred to this data will have no reference destination, and will have the same number or file name as the deleted data. When used for other data, there is a problem that wrong data is referred to.

As an example of such a reference relationship, there is a link function for linking the file and the other directory so that the file existing in one directory can be accessed from another directory. . At this time, if the file is deleted from the one directory and the link of the other directory is ignored, the other directory not only becomes inaccessible but also accesses a different file. Problems arise.

In order to cope with such a problem, when deleting a file, a process of examining all directories or files linked to the file and changing the link may be considered. However, it is very difficult to check all directories and the like, and the processing may be complicated. Similarly, the process of simply deleting a link also requires checking all linked files and the like, and the processing load is very large.

[0007] The present invention has been proposed in view of such circumstances, and prevents deletion of data having a reference relationship with other data from affecting the reference relationship of the other data. It is an object of the present invention to provide a data processing device, a data processing method, a data processing system, and a recording medium.

[0008]

In order to solve the above-mentioned problems, a data processing apparatus according to the present invention is a data processing apparatus for processing data recorded on a recording medium. Storage means for storing reference information indicating data of a reference destination of each data and link information indicating the number of data being referred to, based on the reference information and the link information stored in the storage means Management control means for managing the reference relationship of each data in the recording medium, the management means, when deleting the data of the reference destination of one data recorded in the recording medium, the deletion target and New link information is calculated by decrementing the number of link information corresponding to the new data by one, and when the number of new link information becomes zero, the data to be deleted is stored in the recording medium. If the number indicated by the new link information is not zero, the link information of the data to be deleted is updated so as to become the new link information, and the reference information indicated by the reference information of the one data is updated. The data to be deleted is deleted.

In a data processing method according to the present invention, in a data processing method for managing data recorded on a recording medium, reference is made to reference information indicating data of a reference destination for each data recorded on the recording medium. Link information indicating the number of data items stored in the storage medium, and based on the stored reference information and the link information, manages the reference relationship of each data in the recording medium. When the data at the reference destination of the data is deleted, the number of the link information corresponding to the data to be deleted is reduced by one to calculate new link information, and the number of the new link information becomes zero. If the number of the new link information is not zero, the link information of the data to be deleted is deleted from the new link information. Update to be is characterized by deleting the data to be the deletion target from the reference destination indicated by reference information data of the scratch.

[0010] A data processing system according to the present invention includes a recording medium for recording a plurality of data having reference information indicating data of a reference destination and link information indicating the number of data being referenced, and a recording medium for recording on the recording medium. Storage means for storing the reference information and link information for each of the data, and management for managing the reference relation of each data in the recording medium based on the reference information and the link information stored in the storage means. And a management unit having means for managing, when deleting data referenced by one piece of data recorded on the recording medium, link information corresponding to the data to be deleted. Is reduced by one to calculate new link information. If the number indicated by the new link information becomes zero, the data to be deleted is deleted from the recording medium and a new resource is deleted. If the number indicated by the link information is not zero, the link information of the data to be deleted on the recording medium is updated to be the new link information, and the link information is deleted from the reference destination indicated by the reference information of the one data. It is characterized in that the target data is deleted.

According to the data processing method of the present invention, a plurality of data having reference information indicating data of a reference destination and link information indicating the number of data referred to are recorded, and the reference information and link information for each data are recorded. Information is read from the recording medium and stored, the reference relationship between the stored data is managed based on the stored reference information and the link information, and a reference destination of one stored data is managed. When deleting data, the number of link information corresponding to the data to be deleted is reduced by one to calculate new link information, and when the number of new link information becomes zero, the above-mentioned deletion target is deleted. If the number indicated by the new link information is not zero, the link information of the data to be deleted is updated to be the new link information, and the reference information of the one data is deleted. Is characterized by deleting the data to be the deleted from the referenced shown.

A recording medium according to the present invention is characterized by recording a plurality of data having reference information indicating data of a reference destination and link information indicating the number of data referred to.

[0013]

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

The present invention is applied to a memory card system 1 having the configuration shown in FIG. The memory card system 1
It comprises a host computer 10 and a memory card 20.

As shown in FIG. 1, the host computer 1 includes a hard disk 11 for storing various files such as still images and sounds and a directory for managing the files collectively. RAM (Random A)
ccess Memory) 12, a first serial interface (hereinafter, referred to as "first serial I / F") 13 for transmitting and receiving data to and from the memory card 20 via three lines, and controls each circuit. CPU (Central Proc
essing unit) 14, for example, the hard disk 1
1 can be managed in a hierarchical structure using directories.

The RAM 12 is, for example, a hard disk 11
Is temporarily stored in the first serial I / F 13 via a bus, if necessary.
To supply.

The first serial I / F 13 transmits data to the memory card 20 via three lines,
The data stored in the memory card 20 is received.
Specifically, the first serial I / F 13 transmits a serial clock SCK at the time of transmitting the control data and the file via the first line. First serial I /
F13 is a chip select signal CS indicating the state at that time in response to switching of serial data such as file or control data on the first line via the second line.
Is output. Further, the first serial I / F 13 transmits a file or control data to be written to the memory card 20 via the third line,
The file read from 0 is received.

The CPU 14 controls reading of files from the RAM 12 and the hard disk 11, writing of files to the RAM 12 and the like, and controlling transmission and reception of files and the like to and from the memory card 20. For example, the CPU 14
Issues a register command for determining whether write protection of an erroneous erasure prevention switch (not shown) of the memory card 20 is turned on, or writes a predetermined file by designating an address to the memory card 20. Issue

Here, as shown in FIG. 1, the memory card 20 has a second serial I / F for serially transmitting and receiving files and control data from the host computer 1.
21, a flash memory 22 for storing files and directories, and a controller 23 for controlling reading or writing of files and the like stored in the flash memory 22.

The flash memory 22 has, for example, an NA
As shown in FIG. 2, a file transmitted from the host computer 1 is divided and stored in blocks (for example, 8 kbytes or 16 kbytes) serving as an erasing unit. Each block 0, 1, 2, ..., n is
16 data areas for storing 512 bytes of files, etc.
One page (= 512) consisting of a redundant area of bytes
(Byte + 16 bytes). The redundant area stores distributed management information for managing data in the data area of the block. When these pieces of distributed management information are collected, set management information (set management file) is configured. The collective management file is composed of several blocks, and collectively manages data states of all blocks.

There are two types of files: a user file format used for images and sounds, and a system file format used for system management. The file is stored in the data area of one or more blocks of the flash memory 22. You.

As shown in FIG. 3, a file in the user file format is composed of a 512-byte header part as attribute information of the file and a data part as main information. The header section includes a 128-byte OS header which is information for managing the file in the memory card 20, a 240-byte file header which is general and indispensable management information, and a 144-byte entry area. Become. Further, the data section includes a table data area,
And four entry data. In the data section shown in FIG. 3, up to four entry data are stored. That is, a file in the user file format is configured from a maximum of four entry data. FIG.
In the above, the index data, the image data, and the two auxiliary data have been described as examples of the entry data, but the entry data is not particularly limited, and may be other audio data.

As shown in FIG. 4, the OS header includes "file ID" (2 bytes), "file version" (2 bytes), "file size" (4 bytes), and "number of used blocks". "(2 bytes)," Number of links "
(1 byte), "Date" (8 bytes), "Manufacturer / Model code" (4 bytes), "Initial registration directory number" (2 bytes), "Application category"
(1 byte), “File name” (11 bytes), “Keyword registration number” (1 byte), “Keyword character code” (1 byte), “Keyword character string” (32 bytes), “0 reset reserve” ( 4 bytes), "individual data" (32 bytes), and unused area "reserved"
Having.

The "file ID" indicates the type (purpose) of the file, and the file header has the same type. The “file version” indicates a so-called version number, and indicates the host computer 10
The memory card 20 is used to determine whether the file can be processed. “File size” indicates the overall size of the file including the header part and the data part in bytes. The “number of used blocks” indicates the number of blocks using the file in the flash memory 22. “Number of links” indicates the number of directories that refer to the file. The "number of links" includes the directory to which the file belongs. For example, a file that is not referenced from another directory is linked only to the directory to which it belongs, so the “number of links” is one. "Date" indicates the date when the file was created or updated. The “maker / type code” indicates the name of the manufacturer of the device that wrote the file on the memory card 20 and its model. The “initial registration directory number” indicates the directory number registered first, and is not updated even when a file is moved to another directory. “Application category” indicates a category of an application in which this file is used. The “file name” is a file name used when managing files in the host computer 10, and is not particularly used in the memory card 20. "Number of registered keywords"
Indicates the number of registered keywords. “Keyword character code” indicates the character code of the keyword. The "keyword character string" can specify a plurality of keywords by determining a keyword and a separator. "0 reset reserve" is always set to 0 at the time of rewriting. “Individual data” is used for management for each file ID.
This data is used for a purpose determined by the user, and can be used freely by the user.

As shown in FIG. 5, the file header includes "standard identification data" (8 bytes), "file standard identification data" (8 bytes), and "file ID".
(2 bytes), "File version" (2 bytes),
“Application creation date” (8 bytes), “Application update date” (8 bytes), “Creation maker /
“Model code” (4 bytes), “Update manufacturer / model code” (4 bytes), “0 reset reserve” (16 bytes), “Data entry number” (1 byte), “Table number” (1 byte), “ It has a “character code” (1 byte), a “title character string” (128 bytes), and an unused area “reserved”.

The "standard identification data" indicates that the flash memory 22 stores a file according to a predetermined standard. "File standard identification data"
Indicates that the file has been created in accordance with the predetermined standard. "File ID" indicates the type of file, and the OS header has the same type. “File version” indicates a version number. "Application Creation Date"
Indicates the date the application was created,
"Application update date" indicates the date on which the application was updated. "Creation maker / type code"
The maker that created the file and its model name are shown, and the "update maker / type code" shows the maker that updated the file and its model name. The “number of data entries” indicates the number of entry data described later. The “number of tables” indicates the number of data in the table data area. "Character code"
Indicates an input character by a predetermined code number.
"Title character string" indicates a title character.

The entry area stores data (hereinafter, referred to as "entries") for managing four entry data in the data section.

Each entry in the entry area is 4
As shown in FIG. 5, a "start address" is provided for each of the four entry data.
(4 bytes), “data size” (4 bytes), “data type ID” (1 byte), “reserve” (1 byte), and “individual data” (26 bytes). For example,
The “start address” of the entry 1 indicates the leading logical address of the “entry data 1 index” shown in FIG.
The “start address” of the entry 2 indicates the head logical address of the “entry data 2 image data”.

On the other hand, as a file in the system file format, for example, a directory file corresponds, and the configuration of the header portion is different from that in the user file format.

Here, one directory is composed of one file, that is, one directory file, and has a maximum size of 8 kbytes. The directory file is composed of a header section and a data section, and each file is managed mainly by directory information of the header section and a directory entry list of the data section.

The header of the directory file is
As shown in FIG. 6, "OS header" (128 bytes),
It has a "file header" (240 bytes), a "system entry area" (48 bytes), and a "directory information" (96 bytes). The “OS header” and the “file header” are the same as those in the user file format described above.

The "system entry area" is almost the same as that in the user file format, but no individual data is provided for each entry. Specifically, as shown in FIG. 7, for each entry, “start address” (4 bytes), “data size” (4 bytes), and “data type I
D "(4 bytes). For example, the “start address” of one entry indicates the head logical address of group information described later, and the “start address” of another entry.
Indicates the head logical address of a directory entry described later.

"Directory information" is
The directory information is managed. As shown in FIG. 8, “directory ID” (2 bytes), “target file ID” (1 byte), “group number” (1 byte), “parent directory” ( 2 bytes), "Number of directories" (2 bytes), "Number of files (all files)"
(2 bytes), "Number of target files" (2 bytes), "Access point" (2 bytes), "Number of directory entries" (2 bytes), "Number of directory entries for system" (2 bytes), "Used system directory" It has the number of entries (2 bytes), the number of reserved blocks (2 bytes), the number of used blocks (2 bytes), and an unused area "reserve" (72 bytes).

The "directory ID" indicates the type of directory, and the "target file ID" indicates the ID of a file (target file) accessed at high speed in the directory. “Number of groups” is the number of registered groups. "Parent directory" is the parent directory,
That is, it indicates the file number of the next higher layer. “Number of directories” indicates the total number of directories included, and “number of files (all files)” indicates the number of all files included in the directory. "Number of target files" indicates the number of target files included, and "access point" indicates an access start directory entry. The “number of directory entries” indicates the number of used user directory entries, and the “number of directory entries for the system” indicates the number of directory entries for the reserved system. The “number of used system directory entries” indicates the number of directory entries for the system, the “number of reserved blocks” indicates the number of blocks of the flash memory 22 that the application wants to reserve, and the “number of used blocks” indicates the number of blocks used by the application.

The data section of the directory file has "group information" (variable length) as entry data 1 and "directory entry list" (variable length) as entry data 2 as shown in FIG. .

"Group information" is shown in FIG.
As shown in the table, "group number" (1 byte), "group information size" (1 byte), "directory ID" (2 bytes), "0 reset reserve"
(1 byte), "Reserve" (3 bytes), "Date"
(8 bytes), “individual data” (8 bytes), and “title” (variable length).

The "group information" is information for grouping desired files in a directory. As will be described later in detail, a pseudo directory is provided substantially in a hierarchy below the directory. The “group information size” indicates the size of the group information, and has a fixed length of 24 bytes plus an arbitrary number of bytes of “title”. “Directory ID” is an ID assigned to each directory type, and “0 reset reserve” is always set to 0 when it is corrected. “Reserve” is set to 0 when the file is created. "Date" indicates the creation date of the file, which can be changed by the user. "Individual data" is not particularly defined, and "Title" indicates the title of the directory file.

The "directory entry list" indicates the elements belonging to the directory, and is composed of a plurality of directory entries as shown in FIG. One directory entry is 4 bytes. Directory entries are "file number" (2 bytes), "attribute information" (1 byte), "group number"
(1 byte).

As shown in FIG. 11, the "file number" has "0" in the first bit of the 2 bytes, and the remaining 15 bits indicate the head logical address of the file or directory. “0xffff”
When is shown, it means unused.

The “attribute information” is, as shown in FIG.
“Directory / file” (1 bit), “target flag” (1 bit), “mark 1” (1 bit), “mark 2” (1 bit), “continuous recording” (2 bits), “reserve” ( 2 bits) of information. "Directory / file" indicates that there is a further directory below the directory when it is 1, and that there is a file when it is 0. When the “target flag” is “1”, it indicates that the file has the target file ID specified by the directory information described above, and when “0”, it indicates that the file is another file. That is, when the “target flag” is set (1), it means that the file specified by the “file number” can be accessed at high speed in the directory. When the “target flag” is not set (0), the handling differs for each application. "Mark 1" indicates that mark 1 is specified when it is 1.
A value of 0 indicates that there is no such designation. "Mark 2"
Is the same as “Mark 1”. “Mark 1” and “Mark 2” are marking flags that can be specified by the user. “Continuous recording” indicates that the file is a normal file when 00, 11 is a leading continuous file, and 10 is a continuously designated file.

As shown in FIG. 13, the "group number" is a group number represented by 8 bits and indicating one pseudo layer. Thus, files having the same group number in the same directory are handled as one group. The file of group number 0 is
Nothing is grouped, and when it looks like a directory, it will be directly under the directory.

Here, it is assumed that nine files from file 1 to file 9 exist in the same directory. Further, files 1, 5, and 7 belong to group 1,
Files 2 and 4 belong to group 2, files 3 and 6 belong to group 3, and files 8 and 9 belong to group 0.

At this time, as shown in FIG. 14, the groups 1 to 3 are located in a hierarchy below the directory, and play a role as if the directory existed in a pseudo manner. However, no additional directory can be provided under the group. The files 8 and 9 belonging to the group 0 are handled as those immediately below the directory.

As shown in FIG. 15, for example, each group does not need to be handled like a pseudo directory, and may be handled simply as indicating files having a group relationship.

In the memory card system 1 configured as described above, the CPU 14 of the host computer 10
Reads the directory file of the root directory at the logical address 0, other directory files, and the header of necessary files from the flash memory 22 of the memory card 20, and manages each file.

More specifically, the CPU 14 reads information such as the title and date from the file header in the header section of all files, reads the start position of the directory entry area, data size, etc. from each entry in the entry area. Based on the system information of the directory file, the system entry list, and the like, a root directory and a hierarchical directory structure serving as a backbone are configured. Then, for example, the CPU 14 shown in FIG.
As shown in FIG. 6, a hierarchical structure of all files and all directories can be formed.

In FIG. 16, the root directory of the logical address 0 is located at the highest hierarchy as a backbone, and manages other directories and a plurality of files. The directory located below the root directory also manages other directories and multiple files.

Each file may not only belong to one directory but also have a relationship referred to from another directory.

For example, as shown in FIG.
It is assumed that file 4 belongs to directory 1, file 5 belongs to directory 2, and file 6 belongs to directory 3. At this time, it is assumed that the directory 2 refers to the files 3 and 4, and the directory 3 refers to the files 4 and 5.

Conventionally, for example, when file 3 is deleted from directory 1, directory 2 may not be able to refer to file 3 or the reference destination may be replaced by another file. Therefore, each file has information on the number of links to the directory by providing the “link number” in the OS header so that no inconvenience occurs even if the linked file is deleted. Specifically, when deleting a file, the CPU 14 of the host computer 10 executes step S1 shown in FIG.
Step S4 is performed.

In step S1, the CPU 14 reads the header (512 bytes) of the file to be erased from the flash memory 22 and
To be stored. Then, the "number of links" in the OS header
(For example, n) is reduced by one to (n-1), and in the directory to which the file to be erased belongs, the directory entry list of the directory file relates to the file to be erased. The directory entry is deleted, and the process proceeds to step S2.

In step S2, the CPU 14 determines whether or not the new "number of links", that is, (n-1) is zero. If it is determined that the value has become zero, the process proceeds to step S3, where the value is not zero. When the determination is made, the process proceeds to step S4.

In step S 3, the CPU 14 deletes the file to be erased from the flash memory 22.
The process of deleting from is performed.

On the other hand, in step S4 when it is determined in step S2 that it is not zero, the CPU 1
4 is O in order to make (n-1) a new "number of links".
The S header is updated and written to the flash memory 22.

As a result, for example, when the file 2 shown in FIG. 17 is to be deleted from the directory 1, the directory entry relating to the file 2 is deleted from the directory 1 and the “link number” is determined by the processing in step S1. Is changed from 1 to 0, and step S
2, through the process of step S3, the data is actually deleted as shown in FIG.

On the other hand, when the file 3 is to be deleted from the directory 1, the directory entry relating to the file 3 is deleted from the directory 1, and the “link number” is set to 2 by the processing of step S1.
From 1 to Since the link from the directory 2 of the file 3 has not been deleted, as shown in FIG. 19, the file 3 is reduced by the "number of links" through the processing of steps S2 and S4 without being deleted. The same applies to file 5.

Next, how files are easily linked via a directory will be described with reference to FIG. Here, a case where a camera directory and a print directory are formed with the root directory as a base will be described as an example.

In FIG. 20, the image 1 file, the image 2 file, and the image 3
A file, an image 4 file, and an image 5 file are provided. Also, in the hierarchy under the print directory,
For example, a print file is provided in which information such as the size and the number of printouts is recorded.

Here, the print directory has an image 1 directory entry, an image 2 directory entry, and an image 3 directory entry in the directory entry list shown in FIG. 10 as well as the directory entry indicating the print file. The image 1 directory entry includes the file number and attribute information of the image 1 file, and the image 2 directory entry includes the file number and attribute information of the image 2 file. The same applies to the image 3 directory entry and the image 4 directory entry. In the print directory, the "target flag" is set in the directory entry indicating the print file, and the "target flag" is not set in the directory entries corresponding to the image 1 file to the image 4 file.

Thus, the print directory can access the print file at a high speed, and is linked to the image 1 file to the image 4 file. In other words, the print file is linked to the image 1 file to the image 4 file via the print directory. At this time, when the print file is executed, the images of the image 1 file to the image 4 file are printed out in a predetermined size and number through the print directory.

Next, a case where the image 2 file is deleted from the camera directory will be described. Image 2
The file is linked to the camera directory and the print directory. Therefore, the above step S1
In the above, the “number of links” changes from “2” to “1”. Then, in steps S2 and S4, the directory entry relating to the image 2 file is deleted from the camera directory, but the image 2 file is not actually deleted, only the header is updated. As a result, the print file can print out the image 2 file even if the image 2 file is deleted from the album 1 directory.

The print directory can own a plurality of print files by using the group function. In FIG. 21, groups 1 and 2 are provided in a hierarchy below the print directory. Here, the directory entry of the print file and the directory entries of the images 1 to 4 shown in FIG. 20 are group 1, and the directory entry of the print file 2 and the directory entry of image 5 are group 2. By executing the print file 1, the images of the image 1 file to the image 4 file can be printed out, and by executing the print file 2, the image of the image 5 file can be printed out. Images to be output can be grouped.

As described above, it is possible to easily link files with each other through the directory. That is, when linking one file with another file, it is only necessary to register the “file number” of the other file in the directory entry of the directory to which the one file belongs.

On the other hand, when trying to directly link a file with another file, it is necessary to check the inside of the file to check the linked data. In this case, as the number of types of files increases, the structure of all files must be understood, and the processing load for examining the inside of the files increases. In particular, the number of files having different structures tends to increase as the number of applications increases, so that the processing load on the host computer 10 increases.

However, as described above, when files are linked via a directory, even if the types of files increase, the link destination can be easily changed by checking the directory entry of the directory of the file as the link source. You can find out.

When a file is to be deleted from a directory, the file is not actually deleted when the file is referenced from another directory, so that the file can be accessed from the linked directory. . That is, in this case, since the file is not actually deleted, it is possible to avoid that the directory is linked to a different file. Also,
When deleting a file, only the "link count" of this file is checked, so there is no need to check all the files linked to this file, and the processing load is greatly reduced compared to the past. it can.

In this embodiment, a memory card having a flash memory has been described as an example of a recording medium. However, the present invention is not limited to this. It is also applicable to media.

[0068]

As described above in detail, according to the data processing apparatus and the data processing method according to the present invention, when deleting the reference data of one data stored in the recording medium, the data is deleted. New link information is calculated by reducing the number of link information of the target data by one, and when the number of new link information becomes zero, the data to be deleted is deleted from the recording medium, and the new data is deleted. If the number indicated by the new link information is not zero, the link information of the data to be deleted is updated to be new link information, and the data to be deleted is deleted from the reference information of one data, so that the reference is performed. Even when the previous data is deleted, when this data has a reference relationship with a plurality of data, it is possible to prevent the data from actually being deleted and maintain the reference relationship with other data.

According to the data processing system and the data processing method according to the present invention, the control unit of the control unit becomes a deletion target when deleting the reference data of one data stored in the recording medium. New link information is calculated by reducing the number of link information indicated by the data by one, and when the number of new link information becomes zero, the data to be deleted is deleted from the recording medium, and the new link information is deleted. Is not zero, the link information of the data to be deleted on the recording medium is updated to be new link information, and the data to be deleted is deleted from the reference information of one piece of data. Even when the previous data is deleted, when this data has a reference relationship with a plurality of data, it is possible to prevent the data from being actually deleted and maintain the reference relationship with other data. That.

According to the recording medium of the present invention, by storing a plurality of data having reference information indicating the data of the reference destination and link information indicating the number of times of reference, the reference information and the link information can be stored. Based on this, it is possible to construct a reference relationship between the plurality of data.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a memory card system to which the present invention is applied.

FIG. 2 is a diagram for explaining a configuration of data stored in a flash memory in a memory card of the memory card system.

FIG. 3 is a diagram for explaining a configuration of a file stored in the flash memory.

FIG. 4 is a diagram for explaining a configuration of an OS header of the file.

FIG. 5 is a diagram for explaining a configuration of a file header and an entry area of the file.

FIG. 6 is a diagram for explaining a configuration of a directory file.

FIG. 7 is a diagram for explaining a configuration of a system entry area of the directory file.

FIG. 8 is a diagram for explaining the structure of directory information of the directory file.

FIG. 9 is a diagram for explaining the structure of group information of the directory file.

FIG. 10 is a diagram for explaining a configuration of a directory entry list of the directory file.

FIG. 11 is a diagram for explaining file numbers in the directory entry list.

FIG. 12 is a diagram for explaining attribute information of the directory entry list.

FIG. 13 is a diagram for explaining group numbers in the directory entry list.

FIG. 14 is a diagram for explaining the handling of groups in a directory.

FIG. 15 is a diagram for describing handling of groups in a directory.

FIG. 16 is a diagram for explaining a directory hierarchy composed of directories and files.

FIG. 17 is a diagram illustrating a reference relationship between directories and files.

FIG. 18 is a flowchart illustrating an operation of a CPU when deleting a file.

FIG. 19 is a diagram illustrating a reference relationship between directories and files.

FIG. 20 is a diagram illustrating a reference relationship between a print directory and an image file.

FIG. 21 is a diagram illustrating a reference relationship between a print directory and an image file.

[Explanation of symbols]

1 memory card system, 10 host computer, 11 hard disk, 12 RAM, 13 first
Serial I / F, 14 CPU, 15 20 memory card, 21 second serial I / F, 22 flash memory, 23 controller

Claims (5)

[Claims] 1. A data processing apparatus for processing data recorded on a recording medium, comprising: a reference information indicating a reference destination data for each data recorded on the recording medium; and a number of referred data. Storage means for storing link information to be indicated, and management control means for managing a reference relationship of each data in the recording medium based on the reference information and the link information stored in the storage means, The means, when deleting reference data of one piece of data recorded on the recording medium, reduces the number of link information corresponding to the data to be deleted by one to calculate new link information. When the number indicated by the new link information becomes zero, the data to be deleted is deleted from the recording medium, and when the number indicated by the new link information is not zero, the data to be deleted is deleted. A data processing apparatus for updating data link information so as to become the new link information and deleting the data to be deleted from the reference destination indicated by the reference information of the one data. 2. A data processing method for managing data recorded on a recording medium, comprising: reference information indicating reference destination data for each data recorded on the recording medium; and indicating the number of referenced data. Link information is stored, a reference relationship of each data in the recording medium is managed based on the stored reference information and the link information, and reference data of one data recorded in the recording medium is stored. Is deleted, the number of link information corresponding to the data to be deleted is reduced by one, new link information is calculated, and when the number of new link information becomes zero, If data is deleted from the recording medium and the number indicated by the new link information is not zero, the link information of the data to be deleted is updated to be the new link information, and Data processing method characterized in that from the reference destination reference information data indicates to delete the data to be the deletion. 3. A recording medium for recording a plurality of data having reference information indicating data of a reference destination and link information indicating the number of data referred to, and a reference for each data recorded on the recording medium. A management unit having storage means for storing information and link information, and management means for managing a reference relation of each data in the recording medium based on the reference information and the link information stored in the storage means; The management unit of the management unit, when deleting the reference data of one data recorded on the recording medium, reduces the number of link information corresponding to the data to be deleted by one. If the number indicated by the new link information becomes zero, the data to be deleted is deleted from the recording medium, and if the number indicated by the new link information is not zero, The link information of the data to be deleted on the recording medium is updated to be the new link information, and the data to be deleted is deleted from the reference destination indicated by the reference information of the one data. And a data processing system. 4. A plurality of data having reference information indicating data of a reference destination and link information indicating the number of data referred to are recorded, and reference information and link information for each data are recorded from the recording medium. When reading and storing, managing the reference relation of each of the stored data based on the stored reference information and the link information, and deleting the reference data of one stored data, The number of the link information corresponding to the data to be deleted is reduced by one to calculate new link information. When the number of the new link information becomes zero, the data to be deleted is deleted, and the new data is deleted. If the number indicated by the new link information is not zero, the link information of the data to be deleted is updated so as to become the new link information, and the link information is deleted from the reference destination indicated by the reference information of the one data. Data processing method and deletes the data to be. 5. A recording medium for recording a plurality of data having reference information indicating data of a reference destination and link information indicating the number of data referred to.