JPH1124979A - Information recording method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a processing speed and to drastically save record capacity by adding only a sector that includes data to be rewritten among files recorded on a record medium. SOLUTION: A device driver calculates a sector address that includes a data area which is made a rewrite request from an application, that is, a rewrite start sector and end sector (step 201). The device driver controls drive, reads data of a sector corresponding to it from an optical card and stores it in a buffer which is reserved by the device driver (step 202). Data to be rewritten are overwritten on data of the buffer, and the data of the buffer are rewritten (step 203). When data rewrite is finished, the data stored in the buffer are recorded on an optical card (step 204). Consequently, the larger a file size is, the less the possibility that the capacity of record medium drops is, and information can be effectively rewritten.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording method for recording information on an information recording medium, and more particularly to a method for rewriting data in an existing file.

[0002]

2. Description of the Related Art Hitherto, as information recording carriers, optical disks and optical cards for optically recording and reproducing information, and fixed magnetic disks and floppy disks for magnetically recording and reproducing information have been known. In general, these information recording carriers are composed of a track composed of a plurality of sectors, and a track address indicating a position in the carrier at the time of manufacturing or formatting the carrier is assigned to the track. And
When recording and reproducing information, a desired track is searched based on the track address, and information is recorded and reproduced on a target track. Each sector is also assigned a sector address according to the track address.

A general-purpose block device (random access device) such as a hard disk or a floppy disk usually has a device driver attached to an OS (Operating System) from the beginning. On the other hand, a new record carrier such as an optical card is usually provided with a device driver and a library from a drive maker, and the optical card is a write-once record carrier. Pseudo random access is enabled for each sector of the card.

Next, a method of recording file data on an optical card using such a device driver will be described. FIG. 13 shows the recording surface of the optical card. First, the recording area of the optical card 1 is divided into a directory area A and a data area B. The capacity of one sector is 512 bytes. It is also assumed that the data of the file A is recorded in the sectors S0 to S2 on the optical card 1, and the directory D1 for managing the file A is recorded in the directory area. FIG. 14 shows the contents of the directory D1. The directory number 9 is “1”, the file name 10 is “file A”, and the first sector address 11
Is "0", the number of exclusive sectors 12 is "3", and the file capacity 13 is "1536 bytes". The append number 14 and the erasure flag 15 will be described later in detail.

A method for recording the file B on such an optical card will be described with reference to FIG. The file B is, for example, 1200 bytes. In FIG. 15, first, in step 101, a file B is opened for recording. At this time, nothing is recorded on the optical card. Next, in step 102, the data of the file B is recorded on the optical card. Since the sectors S0 to S2 have already been recorded, the data of the file B is stored in the sector S as shown in FIG.
Record in 3-S5. When recording is completed, step 10
In step 3, file B is closed.

[0006] The file is closed by recording a directory D2 for managing the file B on the optical card 1. FIG. 14 shows the contents of the directory D2. The directory number is “2”, the file name is “file B”, the start sector address is “3”, the number of sectors is “3”, and the file capacity is “1200 bytes”.

Here, the append flag is used for managing a file as one file when adding data to an existing file on the optical card. The deletion flag is used to delete a file in a pseudo manner. The applicant of the present invention has disclosed a method of appending a file to an optical card in Japanese Patent Application Laid-Open Nos. 1-258288 and 4-14.
It is disclosed in, for example, Japanese Patent Publication No. 1867. That is, a number (append flag) indicating the addition of file data is provided in the directory, and when adding data to an existing file, the data to be added is recorded as a separate file, and the additional file data (partial file ) Is recorded by incrementing the append flag, and files having the same file name but different append flags are managed as one file divided in the order of the append flag number.

Next, a method of appending a file will be described. First, a description will be given assuming that 200 bytes of data are appended to file A among the files of the optical card on which file A and file B are recorded as shown in FIG. In FIG. 13, sectors S0 to S2 are data of file A, and sectors S3 to S5 are data of file B. To add data to file A in this state, first, file A is opened in append mode, and then the data to be appended is recorded on the optical card. Since data is recorded on the optical card up to the sector S5, additional data is recorded on the sector S6.

Next, when closing the file A, a directory D3 for managing an additional file is recorded. FIG. 16 shows the sector S recorded in this manner.
6, directory D3. FIG. 17 shows the contents of the directory D3. In this case, the directory number is “3”, the file name is “file A, the head sector address is“ 6 ”, the number of sectors is“ 1 ”, and the file capacity is“ 200 bytes ”. 14 increments the append number "1" of the directory D1 of the file A in FIG.
It has become. In this way, the directory of the additional file is the same as the original file name, and the append flag is incremented to add the file,
It is understood that the file A is divided and recorded in the order of append flags 1 and 2 from the directories D1 and D3, and a file having the same file name can be managed as one file.

[0010] The applicant of the present application has disclosed a method of erasing a file recorded on a write-once recording medium in a pseudo manner, as disclosed in
No. 91888. In this method, a file is erased in a pseudo manner by recording a directory indicating that an already recorded file has been erased. Conventionally, an existing file is rewritten using this erasing method. This erasing method will be specifically described.

First, as described above, it is assumed that the data of the file A is recorded in the sectors S0 to S2 and S6 on the optical card 1 and the data of the file B is recorded in the sectors S3 to S5. It is assumed that 100-byte data is rewritten from the position of the 600-byte offset from the head. To rewrite a part of the data of the file B, the data of the file B is stored in a buffer (not shown) of the recording / reproducing apparatus, and the erasure directory D4 as described above is recorded on the optical card to erase the file B. FIG. 17 shows the contents of the erase directory D4.
The erasure flag 15 of the erasure directory D4 is "1". When this flag is "1", the file B is regarded as having been erased.

On the other hand, when the erasure flag is "0", it indicates that the file is a newly recorded file or a directory for managing additionally recorded data. Next, 100 bytes of data are rewritten from the offset position of 600 bytes from the head of the data stored in the buffer, and the rewritten data of the buffer is recorded in sectors S7 to S9 of the optical card as shown in FIG. Also, as shown in FIG. 16, a directory D5 for managing data of the sectors S7 to S9 is recorded. FIG. 17 shows the contents of the directory D5. The directory D5 manages the data of the sectors S7 to S9 of the rewritten file B, and has a leading sector address of "7" and a number of sectors of "3".

[0013]

However, in the conventional rewriting method, all the file data including the part which is not actually rewritten is re-recorded at another position. And the area required for recording on the write-once type recording medium is reduced.

The present invention has been made in consideration of the above-described conventional problems, and has as its object to provide an information recording method in which the capacity of a recording medium is not reduced by rewriting only a sector including data to be rewritten and additionally recording. .

[0015]

SUMMARY OF THE INVENTION It is an object of the present invention to obtain a sector address including data to be rewritten among file data to be rewritten recorded on a write-once recording medium, and to rewrite the sector address. A step of creating data, a step of appending the created data to the recording medium, a step of recording a directory in which the file to be rewritten is erased in a pseudo manner, and a step of managing the rewritten file. And recording the directory on the recording medium.

[0016]

Embodiments of the present invention will be described below in detail with reference to the drawings. First, the first of the present invention
An embodiment will be described. FIG. 1 shows an example of the configuration of an information recording / reproducing system including a host computer and an information recording / reproducing device according to the first embodiment of the present invention. In FIG. 1, reference numeral 31 denotes an information recording / reproducing apparatus (hereinafter referred to as a drive) for recording and reproducing information on an information recording carrier.
The drive 31 is a host computer 32 of the host controller.
And records and reproduces information under the control of the host computer 32. The optical card 1 is used as an information recording carrier. 37 drives a transport mechanism (not shown) to introduce the optical card 1 into a predetermined position in the drive 31;
A card feed motor for reciprocating the optical card 1 in the R direction at a predetermined position and further discharging the optical card 1 out of the apparatus. Reference numeral 38 denotes a light beam irradiation optical system including a semiconductor laser as a light source, and irradiates the optical card 1 with a light beam of the light source focused on a minute light spot when recording and reproducing information.

Reference numeral 39 denotes a photodetector for detecting light reflected from the optical card 1; AF actuator for performing autofocus control by moving in the direction, that is, the direction perpendicular to the optical card surface,
Reference numeral 41 denotes an AT actuator for driving a part of the light beam irradiation optical system 38 to move a light spot on the optical card 1 in the Y direction, that is, in a direction orthogonal to the information track of the optical card, thereby performing an automatic tracking control. It is. An optical head 50 includes the light beam irradiation optical system 38, the photodetector 39, the AF actuator 40, and the AT actuator 41. Numeral 36 denotes a head feed motor for moving the optical head 50 in the Y direction to access the light spot to a desired track.

The MPU 33 is a processor circuit for controlling each unit in the drive 31, and has a built-in ROM and RAM. The MPU 33 controls a head feed motor 36, a card feed motor 37, and the like, and transmits and receives data to and from the host computer 32. The AT / AF control circuit 34 drives the AF actuator 40 and the AT actuator 41 based on the output signal from the photodetector 39 so that the light spot from the light beam irradiation optical system 38 is focused on the card surface. In addition, auto focus control and auto tracking control are performed so that the light spot scans following the information track.

The modulation / demodulation circuit 35 is a circuit for modulating recording information under the control of the MPU 33 and demodulating reproduction information. At the time of recording information, the recording data from the host computer 32 is modulated by the modulation / demodulation circuit 33, the light source in the light beam irradiation optical system 38 is driven according to the modulation signal, and the intensity-modulated light beam is scanned on the information track. By doing so, information is recorded on the optical card 1.

At the time of reproducing information, a light beam for reproduction is irradiated onto the information track of the optical card 1 from the light beam irradiation optical system 38, and the light detector 39 detects the reflected light from the optical card 1. Then, a photodetector 39 is provided by the modulation / demodulation circuit 35.
The recorded information is reproduced by performing predetermined signal processing such as binarization and demodulation based on the signal. In general, the optical card 1 has a high error rate due to the nature of the medium, and therefore, if highly reliable information recording is required, an error correction means is required.

Here, usually, a hard disk or a floppy disk is mounted on the host computer 32 as a secondary storage device, and device drivers for the hard disk and the floppy disk are previously provided as standard equipment in the OS. On the other hand, a device driver for an optical card, which is a new device, is provided by a drive maker as described above, and provides functions similar to those of a conventional device, thereby facilitating application development.

Next, a device driver for the above optical card will be described. The device driver used in this embodiment is similar to the device driver of a hard disk or a floppy disk used in UNIX or MS-DOS, and is used to open and write files.
It has read and file close functions. In UNIX and MS-DOS, the C language is mainstream. In the C language, functions fopen (), fread (), fwrite (), fwrite (), which are functions for recording data as files.
seek () and fclose () are provided as standard. These functions are a simple way to access the device drivers of various random devices, ANSI-X3J
11 (American National Standards Institute X3j11
).

The syntax of these functions will be described. First, the syntax of the fopen () function is FILE * fopen (const char * filename, const char * mode
); filename is the address of the file name to be opened, and mode is the address of a memory that describes the mode of the file to be opened. The modes include “record”, “read”, and “append” (append). The return value of the function is the address of the FILE structure, fwrite (),
Used by file access functions such as fread (), fseek (), fclose (). In the following description, size t is
Usually replaced by unsigned int.

The syntax of the fwrite () function is size t fwrite (const void * ptr, size t size, size
tn FILE * stream); ptr is the address of the recording data, size * n is the size of the recording data, and stream is the return value of the fopen () function.
This is the address of the LE structure.

The syntax of the fread () function is size t fread (void * ptr, size t size, size tn, FI
LE * stream); ptr is the address of the recording data, size * n is the size of the recording data, and stream is the return value of the fopen () function.
This is the address of the LE structure.

The syntax of the fclose () function is int fclose (FILE * stream); stream specifies the return value of the fopen () function.

Next, the information recording method according to the present embodiment will be specifically described. In the present embodiment, it is assumed that file management is performed using the append number and the erase flag described above, and the sector size is 512 bytes. In the present embodiment, as shown in FIG. 13, it is assumed that the file A, the file B, and the directories D1 and D2 for managing the file A and the file B are recorded on the optical card 1, and among the data of the file B, It is assumed that the data having a size of 100 bytes is rewritten from the offset position of 600 bytes from. The optical card 1 is set in the drive 31 shown in FIG. 1, and all directories D1 and D2 (FIG. 14) recorded on the optical card 1 are read into the work memory (not shown) of the device driver. Shall be.

When rewriting a part of the data in the file B, usually, the application on the host computer 32 opens the file B for reading and writing by using the fopen () function to the device driver. The device driver checks whether the entry of the file B exists in the directory in the work memory, and if it does not exist, notifies the application of an error by a return value of the fopen () function. When the entry of the file B exists, the application moves the file pointer to the target address to be rewritten.
Execute the fseek () function. In this case, since the data after the 600th byte from the beginning of file B is rewritten,
A parameter indicating the beginning of the file is specified in the whence parameter, and 600 is specified in the offset parameter.

Next, the application executes fwrite ()
Data to be rewritten into a function (100 bytes in size)
Is specified. FIG. 2 shows the processing of the device driver for the fwrite () function. In FIG. 2, first, in step 201, the device driver calculates a sector address including a data area requested to be rewritten by an application, that is, the addresses of a start sector and an end sector to be rewritten. In this case, since the address of the data to be rewritten is from 600 to 699, the sector address to be rewritten is calculated from this address. The address of the start sector to be rewritten is obtained by the following equation (1). However,
The following calculations are all performed in the integer range with the decimal part rounded down.

Start sector = (start address of data to be rewritten / sector size) + start sector address of file ... (1) Since the start address of the data to be rewritten is 600, the sector size is 512, and the start sector address of file B is 3, , Start sector address = (600/512) +3
= 4.

The address of the end sector to be rewritten is obtained by the following equation (2).

End sector = (end address of data to be rewritten / sector size) + first sector address of file ... (2) Since the end address of the data to be rewritten is 699, the sector size is 512, and the first sector address of file B is 3, End sector address = (699/512) + 3 = 4. From the above results, both the start sector address and the end sector address are 4, and the device driver calculates
In step 202, the drive 31 is controlled to read the corresponding data of the sector S4 from the optical card 1 and store the data in the buffer secured by the device driver.

Next, the device driver overwrites the data to be rewritten in step 203 with the data in the buffer, and rewrites the data in the buffer. When the data rewriting is completed, the drive 31 is controlled in step 204, and the data stored in the buffer is recorded on the optical card 1. In this case, since the data has been recorded up to the sector S5 as shown in FIG. 13, the data is recorded in the next sector S6. FIG. 4 shows the optical card after recording in this manner. Sector S6 is the data of the rewritten sector of file B. Thus, the processing for the recording request by the fwrite () function of the application ends. When rewriting all the data in the sector, it is not necessary to read the data from the optical card, but it is sufficient to create the data to be rewritten on the buffer. This is all the same in the following description.

Next, the processing of the device driver when the application issues a close request by the fclose () function will be described. FIG. 3 shows the closing process of the device driver in this case. In FIG. 3, first, in the device driver, step 301
The file B for which rewriting has been requested is deleted in a pseudo manner. This file erasure is performed by pseudo-erasing the file by recording an erasure directory as in the conventional case. FIG. 5 shows the erase directory D3 in this case. The erasure directory D3 has a directory number "3", a file name "file B", an erasure flag "1", and all others are "0". By setting the erasure flag to "1" as described above, the file is deleted. B is considered to be erased. In FIG. 5,
Directories D1 and D2 are the same directories as in FIG.

In the device driver, management information for managing the rewritten file B in step 302 is created. More specifically, as shown in FIG. 5, management information including three directories D4 to D5 is created. D4 is a directory for managing data of the first sector S3 constituting the file B, and D5 is a sector S6 obtained by rewriting the original sector S4 of the file B.
D6 is a directory for managing the data of the sector S5.

As shown in FIG. 5, the directory D4 has a directory number "4", a file name "file B", a head sector address "3", a sector number "1", a sector capacity "512", an append number "1", The erasure flag is “0”. The directory D5 has a directory number “5”, a head sector address “6”, a sector number “1”, a sector capacity “512”, and an append number “2”. The directory D6 has a directory number “6”, a head sector address “5”, a sector number “1”, a sector capacity “176”, and an append number “3”.

When the management information is created, the device driver controls the drive 31 in step 303 and records the created management information in the directory area of the optical card 1. The erase directory D3 and the directories D4 to D4 in FIG.
D6 is a directory recorded by the file closing process. Thus, the process of rewriting a part of the data of the file B is completed.

Next, the operation of once removing the optical card 1 on which data has been recorded as described above from the drive 31 and setting it in the drive 31 again to reproduce the file B will be described. The optical card 1 is already set in the drive 31, and the optical card 1 is stored in the work memory of the device driver.
It is assumed that all directories (the directories in FIG. 5) have been read. When the file B is opened for reading from the application, the fopen () function is used.

In response to this open request, the device driver searches the directory read into the work memory and checks whether the specified file B is recorded on the optical card 1. Although the file B is once pseudo-erased by the erasing directory D3, since the directories D4 to D6 are recorded for the file B, the file B can be normally opened. If the specified file name does not exist in the directory, an error is notified to the application and the processing ends.

Next, the application transmits the file B (1
When reading (200 bytes), first, the first 512 bytes are read in accordance with the directory D4. That is, the device driver controls the drive 31, reads the data of the first sector S3 according to the directory D4 in FIG. 5, and transfers the data to the application. Subsequently, from the 513th byte to the 1024th byte, the data of the sector S6 is read in accordance with the directory D5 and passed to the application. From the 1025th byte to the 1200th byte, the first 176 bytes of the data of the sector S5 are read out according to the directory D6 and passed to the application. 1
Since no directory is managed for a request for data after 201 bytes, an error code "End of Fie" is passed to the application to notify that the request is an error. Thus, the reading of the file B is completed.

Next, the above description is for the case of rewriting the data of the central sector S4 of the sectors of the file B. The method for rewriting the data of the first sector of the file B will be described. Also in this case, the file A and the file B are recorded on the optical card 1 as shown in FIG.
The description will be made on the assumption that the data of the size of 50 bytes is rewritten from the offset position of 100 bytes from the head of the data of the file B.

When a part of the data of the file B is rewritten, the file B is similarly opened from the application to the device driver using the fopen () function for reading and writing. Next, the application executes the fseek () function to move the file pointer to the target address to be rewritten. In this case, since the data after the 100th byte from the beginning of the file B is rewritten, the parameter indicating the beginning of the file B is specified in the whence parameter, and 100 is specified in the offset parameter. Next, the application specifies the data to be rewritten in the fwrite () function, and the device driver
The recording process of FIG. 2 is executed for the te () function.

First, in step 201 of FIG. 2, a start sector address and an end sector address where data requested to be rewritten are recorded are calculated. In this case, since the address of the data to be rewritten is from 100 to 149,
Using this address, as described above, (1), (2)
The addresses of the start sector and the end sector to be rewritten are calculated by the equations. The calculation is similarly performed in the integer range. The starting sector address to be rewritten is 100, the starting address of the data to be rewritten is 100, the sector size is 512, and the starting sector address of the file B is 3, so the starting sector is (100/512) +3. In addition, since the end address of the data to be rewritten is 149, the end sector = (149/512) + 3 = 3.

From the above results, both the start sector address and the end sector address to be rewritten are 3, and the device driver reads the data of the sector S3 of the optical card 1 corresponding to this at step 202 and stores it in the buffer. Next, in the device driver, step 20
In step 3, the data read into the buffer is rewritten, and in step 204, the drive 31 is controlled to record the data in the buffer on the optical card 1. Also in this case, the optical card is in sector S
5, the data of the buffer is recorded in the sector S6. The sector S6 in FIG. 6 is the data of the sector S3 rewritten in this manner.

Next, when a close request by the fclose () function is issued from the application, the device driver similarly executes the close processing of FIG. First, the file B to be rewritten is pseudo-erased by recording the erasure directory in step 301 of FIG. FIG. 7 shows the erase directory D3 in this case. Similarly, the file B is pseudo-erased by setting the erasure flag to “1”. Next, step 302
To create management information for managing the rewritten file B. In this case, management information including two directories D4 and D5 is created as shown in FIG.

The directory D4 is management information for managing the data of the sector S6 after rewriting the original sector S3, and the directory D5 is the sectors S4, S of the file B.
5 is management information for managing the data of No. 5. In this case, since the data of the first sector S3 of the file B has been rewritten, the number of management information is two. As shown in FIG. 7, the directory D4 has a directory number "4", a file name "file B", a start sector address "6", a sector number "1", a sector capacity "512", and an append number "1". The directory D5 has a head sector address “4”, a sector number “2”, and a sector capacity “688” (51
2 + 176), and the append number is “2”. Next, the device driver controls the drive 31 in step 303, records the directory on the optical card 1, and ends the close processing. FIG. 6 shows the optical card after the closing processing. The directories D3 to D5 are directories recorded by the close processing.

Next, when the optical card 1 on which data is recorded as shown in FIG. 6 is once taken out of the drive 31 and set in the drive 31 again to read the file B, the application similarly reads the file B using the fopen () function. Open file B for use. In response to the open request from this application, the device driver searches the directory (the directory in FIG. 7) read into the work memory and checks whether the specified file B is recorded on the optical card 1. Although the file B is once pseudo-erased by the erasure directory D3, since the directories D4 to D5 are recorded for the file B, the file B can be normally opened.

Next, if the application
When reading (1200 bytes), the first 512 bytes are read according to the directory D4. That is, the device driver controls the drive 31, reads the data in the sector S6 according to the directory D4 in FIG. 7, and transfers the data to the application. Next, 12 from the 513th byte
Up to the 00th byte, sector S according to directory D5
4. Read the data of S5 and pass it to the application. Since no directory is managed for a request for data after 1201 bytes, "End of Fie"
Is passed to the application to notify that the request is an error. Thus, the reading of the file B is completed.

Next, a method for rewriting data in the last sector S5 of the file B sectors will be described. In this case as well, the file A and the file B are recorded on the optical card 1 as shown in FIG.
The description will be made on the assumption that byte-sized data is rewritten. Similarly, when rewriting a part of the data of the file B, the application opens the file B using the fopen () function for reading and writing, and moves the file pointer to a target address to be rewritten.
Execute the eek () function. In this case, since the data after the 1100th byte from the beginning of file B is rewritten,
A parameter indicating the beginning of the file B is specified in the whence argument, and 1100 is specified in the offset argument. Next, the application specifies the data to be rewritten to the fwrite () function, and the device driver
(2) The processing of FIG. 2 is executed for the function.

First, in step 201, a start sector address and an end sector address in which data requested to be rewritten are recorded are calculated. In this case, since the address of the data to be rewritten is from 1100 to 1149, the addresses of the start sector and the end sector to be rewritten are calculated by using the addresses according to the equations (1) and (2) as described above. The start sector address to be rewritten is 1100, the sector size is 512, the start sector address of the file B is 3, and the start sector = (1100/512) + 3 = 5. Also, since the end sector address of the data to be rewritten is 1149, the end sector = (1149/512) + 3 = 5.

From the above result, both the start sector address and the end sector address to be rewritten are 5, and the device driver reads the data of the sector S5 of the optical card 1 corresponding to this in step 202 and stores it in the buffer. Next, in the device driver, step 20
In step 3, the data read into the buffer is rewritten, and in step 204, the drive 31 is controlled to record the data in the buffer on the optical card 1. Also in this case, the optical card is in sector S
5, the data of the buffer is recorded in the sector S6.

Next, when a close request by the fclose () function is issued from the application, the device driver similarly executes the processing of FIG. First, step 3
01, an erasure directory is recorded, and the file B to be rewritten is erased in a pseudo manner. FIG. 8 shows the erase directory D3 in this case. Similarly, delete directory D
3 is set to “1”. Next, step 3
In 02, management information for managing the rewritten file B is created. Also in this case, two directories D4 and D5 are created as shown in FIG.

The directory D4 contains the original sectors S3, S
Information for managing the data of directory 4, directory D
Reference numeral 5 denotes management information for managing data in the sector S6 after the rewriting of the original sector S5. Directory D4
As shown in FIG. 8, the directory number is "4", the file name is "file B", the starting sector address is "3", the number of sectors is "2", the sector capacity is "1024", and the append number is "1". The directory D5 has a head sector address “6”, a sector number “1”, and a sector capacity “17”.
6 ”and append number“ 2. ”Next, the device driver controls the drive 31 in step 303 to record a directory on the optical card 1 and ends the close processing.

Next, when the optical card 1 is removed from the drive 31 and set in the drive 31 again to read the file B, the application similarly opens the file B using the fopen () function, and responds to the open request. The device driver searches the directory (the directory in FIG. 8) read into the work memory, and checks whether the specified file B is recorded on the optical card 1. Although the file B is once pseudo-erased by the erasure directory D3, since the directories D4 to D5 are recorded for the file B, the file B can be normally opened.

Next, when the application reads the file B, first, the first 1024 bytes are read according to the directory D4. That is, the device driver controls the drive 31, reads the data in the sectors S3 and S4 according to the directory D4 in FIG. 8, and transfers the data to the application. Subsequently, from the 1025th byte to the 1200th byte, the data of the sector S6 is read out according to the directory D5 and passed to the application. Since no directory is managed for a request for data after 1201 bytes, an error code “End of Fie” is passed to the application to notify that the request is an error. Thus, the reading of the file B is completed.

Next, a description will be given of a rewriting method for rewriting data at two locations in a file. In this case, it is assumed that a file C (2500 bytes in size) and a directory D1 for managing the file C are recorded on the optical card 1 as shown in FIG. FIG. 10 shows this directory D1. The area to be rewritten includes data having a size of 50 bytes from an offset position of 600 bytes from the beginning of the file C (hereinafter, referred to as a first area) and an area of 50 bytes from an offset position of 1900 bytes from the beginning of the file C. It is assumed that the size data (hereinafter, the second area) is rewritten.

When rewriting the data of file C, the application similarly opens file C using the fopen () function, and the device driver checks whether the entry of file C exists in the work memory. Specify the return value of the fopen () function as a value indicating normality. Next, the application rewrites the first area. First, the fseek () function is executed to move the file pointer to the target address to be rewritten. In this case, the first area is 6
Since the data after the 00th byte is rewritten, a parameter indicating the beginning of file C is specified in the whence argument, and offs
Specify 600 in the et argument. Next, the application specifies the data (50 bytes) to be rewritten to the fwrite () function, and the device driver similarly specifies the fwrite () function.
(2) Execute the recording process of FIG. 2 for the function.

First, in step 201, the start sector address and the end sector address where the data requested to be rewritten are recorded are calculated. In the first area, since the address of the data to be rewritten is from 600 to 649, the addresses of the start sector and the end sector to be rewritten are similarly calculated by using the addresses according to the equations (1) and (2). The start sector address of the data to be rewritten is 600, the head address of the data to be rewritten is 5, and the sector size is 5.
12. Since the start sector address of file C is 0, the start sector = (600/512) + 0 = 1. Also, since the end address of the data to be rewritten is 649, the end sector = (649/512) + 0 = 1.

From the above results, the start sector address and the end sector address to be rewritten are both 1. The device driver reads the data of the sector S1 of the optical card 1 corresponding to this at step 202 and stores it in the buffer. Next, the device driver rewrites the data read into the buffer in step 203, and
4 controls the drive 31 to record the buffer data on the optical card 1. In this case, since the data of the file C is recorded up to the sector S4 on the optical card as shown in FIG. 9, the data of the buffer is recorded in the sector S5.

Subsequently, the application rewrites the second area. First, the fseek () function is executed to move the file pointer to the target address to be rewritten. The second area is 1 from the beginning of file C.
Since the data after the 900th byte is rewritten,
Specify the parameter indicating the beginning of file C in the argument, and
Specify 1900 in the fset argument. Next, the application specifies the data (50 bytes) to be rewritten to the fwrite () function, and the device driver similarly specifies the fwrite () function.
(2) Execute the recording process of FIG. 2 for the function.

First, in step 201, a start sector address and an end sector address where data requested to be rewritten are recorded are calculated. In the second area, since the address of the data to be rewritten is from 1900 to 1949, the addresses of the start sector and the end sector to be rewritten are similarly calculated by using the addresses according to the equations (1) and (2). The start sector address to be rewritten is 1900, the sector size is 512, the start sector address of the file C is 0, and the start sector = (1900/512) + 0 = 3. Since the end address of the data to be rewritten is 1949, the end sector address is (1949/512) + 0 = 3.

From the above result, the start sector address and the end sector address to be rewritten are both 3. The device driver reads the data of the sector S3 of the optical card 1 corresponding to this at step 202 and stores it in the buffer. Next, the device driver rewrites the data read into the buffer in step 203, and
In step 4, the data in the buffer is recorded on the optical card 1. In this case, as shown in FIG. 9, since the data up to the sector S5 has been recorded by rewriting the first area, the buffer data is recorded in the sector S6.

Next, when a close request by the fclose () function is issued from the application, the device driver similarly executes the processing of FIG. First, step 3
At 01, the erasure directory D2 is recorded, and the file C to be rewritten is artificially erased. Erase directory D2
Is shown in FIG. Similarly, the erase flag of the erase directory D2 is set to "1". Next, step 302
To create management information for managing the rewritten file C. In this case, five directories D3 to D7 are created as shown in FIG.

The directory D3 is management information for managing data of the sector S0, the directory D4 is management information for managing data of the sector S5 after rewriting the original sector S1, and the directory D5 is the data of the sector S2. Directory D6 is management information for managing data in sector S6 after rewriting original sector S3, and directory D7 is sector S
4 is management information for managing No. 4. Directory D3
Details of D7 are shown in FIG. Directory D4
And D6 are management information for managing the data of the rewritten sector as described above, and the leading sector addresses are "5" and "6", respectively. When the management information is created in this way, the device driver records the directory on the optical card 1 in step 303 and ends the closing process.
In FIG. 9, D2 to D7 are directories recorded by the close process, and sectors S5 and S6 are data recorded by rewriting.

Next, the optical card 1 shown in FIG.
Similarly, when reading the file, the application opens the file C using the fopen () function, and in response to this open request, the device driver searches the directory (the directory in FIG. 10) read into the work memory and specifies the specified file. It is confirmed whether or not the file C is recorded on the optical card 1. Although the file C is once pseudo-erased by the erasure directory D2, since the directories D3 to D7 are recorded for the file C, the file C can be normally opened.

Next, the application sets the file C
(2500 bytes in size), the first 512 bytes are read from the data in the sector S0 according to the directory D3 in FIG.
Up to the 24th byte, sector S according to directory D4
5 data is read and 1536 bytes after the 1,025th byte
Up to the byte, the data in the sector S2 is read according to the directory D5 and passed to the application. Also, 1
From the 537th byte to the 2048th byte, the data of sector 6 is read according to directory D6, and 2049 is read.
The directory D7 from the byte to the 2500th byte
The data of the sector S4 is read out according to the above and transferred to the application. Since no directory is managed for a request for data after 2501 bytes, "End
An error code “of Fie” is passed to the application to notify that the request is an error.

Next, a second embodiment of the present invention will be described. In the previous embodiment, the sector address to be rewritten was calculated by using equations (1) and (2). In the present embodiment, the sector address to be rewritten is obtained based on the directory. In this embodiment, it is assumed that the data of the file B of the optical card 1 of FIG. 6 is rewritten, and the optical card of FIG. 6 partially rewrites the data of the file B as described above. FIG. 8 shows directories D1 to D5 recorded on the optical card. It is assumed that this optical card is set in the drive 31 and all directories D1 to D5 of the optical card have been read into the work memory of the device driver. In this case, it is assumed that 50 bytes of data are rewritten from the offset position of 1100 bytes from the beginning of file B.

When rewriting a part of the data of the file B, the application opens the file B by using the fopen () function, and the device driver checks whether the entry of the file B exists in the work memory. Specify the return value of the fopen () function as a value indicating normality. Also, since the application moves the file pointer to the target address to be rewritten, fseek
Execute the () function. In this case, since the data after the 1100th byte from the beginning of file B is rewritten,
Specify the parameter indicating the beginning of file B in the ce argument,
Specify 1100 for the offset argument. Subsequently, the application writes the data to be rewritten to the fwrite () function (50
Byte), and the device driver also
The processing of FIG. 2 is executed for the rite () function.

First, in step 201, a process for obtaining a sector address in which data requested to be rewritten by an application is recorded is performed. In this embodiment, since the address of the data to be rewritten is from 1100 to 1149, the sector address is obtained based on this address and the directory. Specifically, first, it is determined whether or not the address of the data to be rewritten is included in the management area of the first directory D4 among the directories for managing the file B in FIG. The area managed by the directory D4 is an area from address 0 to address 1023 of the entire area of the file B. Therefore, it is determined whether the address of the data to be rewritten is not included and the address of the data to be rewritten is also included in the management area of the second directory D5.

Since the management area of the directory D5 is an area from the address 1024 to the address 1199 of the file B, it contains the address of the data to be rewritten, and the directory D5 manages only one sector. Therefore, it can be seen that the data to be rewritten is the address 6, that is, the sector S6. When the sector to be rewritten is thus obtained, the device driver reads the data of the optical card into the buffer in step 202, rewrites the data in the buffer in step 203, and records the data in the buffer on the optical card in step 204. In this case, since the optical card has been recorded up to the sector S6, it is recorded in the sector S7 as shown in FIG.

Next, when a close request by the fclose () function is issued from the application, the device driver similarly executes the processing of FIG. First, step 3
At 01, the erasure directory D6 is recorded, and the file B to be rewritten is artificially erased. Erase directory D6
Sets the erase flag to "1" as shown in FIG. Next, in step 302, management information for managing the rewritten file B is created. In this case, FIG.
2, two directories D7 and D8 are created.

The directory D7 is the sector S of the file B.
3, management information for managing the data of S4, the directory D8 is the sector S after rewriting the original sector S6.
7 is management information for managing the data of No. 7. FIG. 12 shows the details of the directories D7 and D8. When the management information is created in this manner, the device driver records a directory on the optical card 1 in step 303, and
The closing process ends. In FIG. 11, D6 to D8
Is a directory recorded by the close processing.

Next, the optical card shown in FIG.
Similarly, the application opens the file B by using the fopen () function, and in response to the open request, the device driver searches the directory (the directory in FIG. 12) read into the work memory and specifies the specified file. It is confirmed whether or not the file C is recorded on the optical card 1. Although the file B is once pseudo-erased by the erasure directory D6, since the directories D7 and D8 are recorded for the file B, the file B can be normally opened.

Next, the application sets the file B
When reading (1200 bytes in size), the first 1024 bytes read the data of the sectors S3 and S4 according to the directory D7 in FIG. 12, and the 1025th byte to the 1200th byte read the data of the sector S7 according to the directory D8. Pass to the application. In addition, since no directory is managed for a request for data after 1201 bytes, "End
The error code "of Fie" is passed to the application to notify that the request is an error, and the reading of the file B is completed.

[0075]

As described above, according to the present invention, all the files are recorded at different positions by additionally writing only the sector containing the data to be rewritten among the files recorded on the recording medium. Compared to the conventional method,
Not only can the processing speed be reduced, but also the recording capacity can be greatly reduced. Therefore, as the file size increases, the capacity of the recording medium does not decrease and information can be rewritten effectively. Further, there is no need to change the conventional reproducing method, and the conventional reproducing method can be used as it is.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration example of a system including a host computer and a drive according to a first embodiment of the present invention.

FIG. 2 is a flowchart for explaining a file rewriting method according to the first embodiment of the present invention.

FIG. 3 is a flowchart illustrating a file closing process according to the first embodiment of the present invention.

FIG. 4 is a diagram showing an optical card in the case where a central sector among sectors of a file recorded on the optical card is rewritten.

FIG. 5 is a diagram showing contents of a directory recorded when rewriting the file of FIG. 4;

FIG. 6 is a diagram showing an optical card in the case of rewriting a first sector among sectors of a file recorded on the optical card.

7 is a diagram showing the contents of a directory recorded when rewriting the file of FIG. 6;

FIG. 8 is a diagram showing the contents of a directory when the last sector of a file recorded on an optical card is rewritten.

FIG. 9 is a diagram showing an optical card in the case of rewriting data at two locations in a file recorded on the optical card.

FIG. 10 is a diagram showing the contents of a directory recorded when rewriting the optical card of FIG. 9;

FIG. 11 is a diagram showing an optical card when rewriting the once rewritten file of FIG. 6 according to the second embodiment of the present invention.

FIG. 12 is a diagram showing the contents of a directory recorded when rewriting the optical card of FIG. 11;

FIG. 13 is a diagram showing an optical card on which a conventional file is recorded.

FIG. 14 is a diagram showing the contents of a directory of the optical card of FIG. 13;

FIG. 15 is a flowchart for explaining a conventional information recording method.

FIG. 16 is a diagram for explaining a conventional file rewriting method.

17 is a diagram showing the contents of a directory recorded when rewriting the file of FIG. 16;

[Explanation of symbols]

 Reference Signs List 1 optical card 31 information recording / reproducing device (drive) 32 host computer 33 MPU 38 light beam irradiation optical system 39 photodetector 50 optical head D1 to D8 directory S0 to S7 sector

Claims (5)

[Claims] 1. A step of obtaining a sector address including data to be rewritten among file data to be rewritten recorded on a write-once recording medium, a step of creating data for rewriting the sector address, Appending data to the recording medium;
Recording a directory for artificially erasing a file to be rewritten on the recording medium, and creating a directory for managing the rewritten file and recording the directory on the recording medium. Information recording method. 2. A head sector address of a sector address including data to be rewritten is calculated by (head address of data to be rewritten / sector size) + a head sector address of a file to be rewritten, and a last sector address is calculated. 2. The information recording method according to claim 1, wherein the calculation is performed by (final address of data to be rewritten / sector size) + first sector address of a file to be rewritten. 3. The information recording method according to claim 1, wherein a sector address including the data to be rewritten is obtained based on an address of the data to be rewritten and a directory for managing a file to be rewritten. 4. The directory for managing a rewritten file includes a directory for managing data of a rewritten sector in a file to be rewritten, and a directory for managing data of a sector other than the rewritten sector. 2. The information recording method according to claim 1, wherein: 5. The information recording method according to claim 1, wherein the recording medium is an optical card.