JP2573579B2 - File operating device for multiple file / volume type magnetic tape - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention creates a new multi-file volume magnetic tape by changing the storage order of a plurality of files stored in a multi-file volume magnetic tape. The present invention relates to a file operation device for a magnetic tape having a plurality of files and a volume format, which is suitable for such a case.

[Conventional technology]

In general, a magnetic tape as an external storage medium used for information processing is stored in a rewound state, so a magnetic tape of a multiple file volume format in which a plurality of files are stored on a magnetic tape of one volume. Then
A file stored in the first part of the magnetic tape requires less time to be actually accessed than a file stored in the second part. Therefore, it is desirable to store frequently used files at the beginning of the magnetic tape in order to improve the utilization efficiency of the computer system.

However, it is not always known when a multi-file / volume-format magnetic tape is first made whether or not it is frequently used. In this case, a new multi-file / volume-format magnetic tape in which the order is changed is created.

In such a case, the first magnetic tape before the change is set in the first magnetic tape device, the second magnetic tape after the change is set in the second magnetic tape device, and stored in the second magnetic tape. It is necessary to perform a process of sequentially reading files from the first magnetic tape in the order to be written and writing the files to the second magnetic tape. In the conventional apparatus, reading and writing of each file are performed by the logical record of each file. I was conscious of it.

[Problems to be solved by the invention]

For this reason, when reading or writing each file, input / output processing cannot be executed unless the operator specifies the format (logical record length, physical record length, etc.) of the file sequentially as a file definition. There is a disadvantage that operations such as changing the order of the files are troublesome.

SUMMARY OF THE INVENTION The present invention solves such a conventional disadvantage, and its purpose is to transfer any file stored on one magnetic tape to another magnetic tape without specifying the file format. Another object of the present invention is to facilitate creation of a new multi-file volume type magnetic tape in which the order of files and the like are changed.

[Means for solving the problem]

In order to achieve the above object, the present invention provides, as shown in FIG. 1, for example, a heading label and a tape mark indicating the end of the file in a multiple file / volume format, and each file has a predetermined identical format in advance. Input means 3 for reading the contents of the blocks sandwiched between the gaps from the first magnetic tape 2 including the following, and storing the blocks in the buffer area;
Output means 6 for writing to the second magnetic tape 5 in block units, designating means for designating a file name of the file stored on the first magnetic tape 2 without designating the format of the file, and input means Determining means 7 for determining whether or not the condition that the block read out and stored in the buffer area is the heading label and the file name included in the heading label is equal to the file name specified by the specifying means; When the determination means 7 determines that the condition is satisfied, the input means 3 writes the block of the heading label stored in the buffer area to the second magnetic tape 5 by the output means 6. The block up to the last tape mark of the file having the file name is input one block from the first magnetic tape 2 by the input means 3. It reads each click, and a control unit 8 for controlling writing to the second magnetic tape 5 by one block by the output unit 6.

[Action]

The input means 3 and the output means 6 read or write the gap and the contents sandwiched between the gaps as one block, and determine the logical contents such as how many logical records are included in the block. Is not conscious, any file stored on the first magnetic tape 2 can be transferred to the second magnetic tape 5 without specifying the file format. By repeating such an operation, To create multiple file volume format magnetic tapes in this order.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 2 is a block diagram of an embodiment of the present invention, in which a central processing unit 10, a main storage device 11, an input device 12, a magnetic tape device 14 on which a first magnetic tape 13 is set, and a central processing unit. A magnetic tape control device 15 for controlling reading and writing of the magnetic tape device 14 in response to a command from the device 10, a magnetic tape device 17 in which a second magnetic tape 16 is set, and a command in response to a command from the central processing unit 10. Read the magnetic tape unit 17,
And a magnetic tape controller 18 for controlling writing.

FIG. 3 is an explanatory diagram of the contents stored on the first magnetic tape 13, and as shown in FIG.
13 has a file F1 with a file name f1, a file name f2
, A file F3 having a file name f3, a file F4 having a file name f4, and a file F5 having a file name f5. Each file has, for example, a heading label FL1 including a file name f1 first, and then a tape mark TM1 across a gap G1 as shown in FIG. Then, there is a record group R constituting the file with the gap G2 interposed, then there is a gap G3, a tape mark TM2, a postscript label LL1 with the gap G4 interposed, and finally there is a gap G5, tape mark TM3, gap G6 There is. Further, as shown in FIG.
The number of records r corresponding to the format of the file is a format in which a gap G is interposed. In the present embodiment, the contents sandwiched between the gaps, that is, the heading label, the tape mark, the number of records corresponding to the format of the file, and the postscript label are read and written as one block. .

FIG. 4 is a flowchart showing an example of a file operation process performed by the central processing unit 10, and among a plurality of files stored on the first magnetic tape 13, a file having a file name designated by the input device 12 or the like. On the second magnetic tape 16 is shown.

Next, a file F3 having a file name f3 among a plurality of files stored on the first magnetic tape 13 shown in FIG.
The operation of the present embodiment will be described by taking as an example the case where is copied to the second magnetic tape 16.

To make such a copy, the operator must use the input device 12.
To input the file name f3 as file information to be selected. When the central processing unit 10 fetches the file selection information (S1), it first issues a one-block reading instruction to the magnetic tape control unit 15 (S2).

When a read instruction of one block is input, the magnetic tape control device 15 activates the magnetic tape device 14 in the forward direction, and the read data sequentially transmitted from the magnetic tape device 14 is stored in the buffer area 11a of the main storage device 11. The transfer is performed, and when one gap is detected, the operation of the magnetic tape device 14 is stopped. In the case of FIG. 3, the content first transferred to the buffer area 11a is the heading label FL1 of the file F1 and the central processing unit 1
When 0 is determined to be the heading label FL1 (S3), it is determined whether or not the file name f1 included in the heading label is the specified file name f3 (S4). Returning to step S2, a read instruction for the next one block is output to the magnetic tape control device 15.

When a read instruction is given, the magnetic tape control device 15 activates the magnetic tape device 14 in the forward direction in the same manner as described above, and sets the tape mark TM1 of FIG.
1a, and the central processing unit 10 returns to step S2 and again gives an instruction to read one block to the magnetic tape control device 15 because the content is not a header label.

Next, the content transferred from the magnetic tape control device 15 to the buffer area 11a is the first set of records in the record group of the file F1 shown in FIG. 3, and is not a heading label. Return to

The above operation is repeated until the heading label including the file name f3 is transferred from the magnetic tape control device 15 to the buffer area 11a, and the center label is transferred to the buffer area 11a when the heading label including the file name f3 is transferred to the buffer area 11a. The processing device 10 determines that the file is a file to be selected (S5), and informs the magnetic tape 16 that the heading label including the file name f3 stored in the buffer area 11a should be written as one block on the second magnetic tape 16. Instruct the control device 18.

In response to this, the magnetic tape control device 18 activates the magnetic tape device 17 in the forward direction, stops writing the heading label including the file name f3, and then stops the operation of the magnetic tape device 17.

When the heading label of the selected file is written on the second magnetic tape 16, the central processing unit 10 gives a reading instruction of one block to the magnetic tape control unit 15 (S7), and the tape mark of the file F3 ( The tape mark corresponding to the tape mark TM1 in FIG. 3 is transferred to the buffer area 11a, and the transferred tape mark is given to the magnetic tape controller 18 as one block. The tape mark is written in the area after the label has been written (S8). The operations of steps S7 and S8 are performed by using the last tape mark of the file F3 (the tape mark TM in FIG. 3).
(S9), whereby all the information of the file F3 stored on the first magnetic tape 13 is copied to the second magnetic tape 16.

As described above, according to the present embodiment, the second magnetic tape can be specified simply by specifying an arbitrary file name stored in the first magnetic tape 13, that is, without specifying the format of the file having that file name. You can copy the file to 16. Therefore, by giving file names sequentially according to the order of files to be stored on the second magnetic tape 16 and omitting designation of file names for files to be deleted, a plurality of files having arbitrary files in an arbitrary order can be obtained. Volume magnetic tape can be created.

FIG. 5 is a flowchart of another process performed by the central processing unit 10, in which a plurality of file / volume magnetic tapes in which the order of one file stored in the first magnetic tape 13 and another file is interchanged is designated once. The following is an example of the creation. Next, the operation of this embodiment is performed by replacing the file F2 having the file name f2 with the file F4 having the file name f4 among the plurality of files stored on the first magnetic tape 13 shown in FIG. An example in which a multi-file volume magnetic tape is created will be described.

The file name α of the file to be replaced by the operator,
When α = f2 and β = f4 are input from the input device 12 as β, the central processing unit 10 takes them in (S10).

Next, the central processing unit 10 reads the first magnetic tape existing before any of the file names f2 and f4 appears.
13 files F1 on the second magnetic tape as shown in FIG.
Copied at the beginning of 16 (S11).

Next, it is determined whether the first file name found among the file names f2 and f4 is α or β (S12). In the case of FIG. 3, the file name f2 (α) is found at first, so the file name f2 (α) is found.
Is stored in the internal register Q, and the remaining file name f4 designated for replacement is stored in the internal register R (S13). When the file name f2 is designated as β, on the contrary, β is stored in the internal register Q and α is stored in the internal register R (S14).

Next, the first magnetic tape 13 is skipped until a file F4 having the file name f4 stored in the internal register R appears (S15). When the file F4 having the file name f4 appears, the file F4 is deleted. As shown in FIG. 6, copying is performed immediately after the file F1 on the second magnetic tape 16 (S16).

Next, the first magnetic tape 13 is rewound (S17), and then the first magnetic tape 13 is skipped until immediately after the file F2 having the file name f2 stored in the internal register Q (S1).
8) Then, the file name f4 stored in the internal register R
The file F3 is copied after the file F4 on the second magnetic tape 16 as shown in FIG. 6 by copying the file F4 on the second magnetic tape 16 up to the file immediately before the file F4 (S19).

Next, the first magnetic tape 13 is rewound (S20) again, and the file having the file name f2 stored in the internal register Q is read.
Skip the first magnetic tape 13 immediately before F2 (S2
1) When the file F2 having the file name f2 appears, the file F2 is copied to the second magnetic tape 16 (S22), and the file F3 of the second magnetic tape 16 is copied as shown in FIG. The file F2 will be stored later.

Next, the first magnetic tape 13 is skipped until immediately after the file F4 having the file name f4 stored in the internal register R (S23), and the file F5 immediately after the file F4 is copied to the second magnetic tape 16. . As a result, as shown in FIG. 6, a multi-file volume magnetic tape in which the files F2 and F4 in FIG. 3 are replaced is completed.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various other additions and changes are possible. For example, the file selection information given in step S1 of FIG. 4 is used as the file name of the file to be deleted in the first magnetic tape 13, and in step S5, step S4
If the file name identified in step is a file name other than the specified file name, steps S6 to S9 are executed, and if YES is determined in step S9, and if the end of the first magnetic tape 13 is not reached, By adding a process to return to S2, it is possible to create a magnetic tape in which all unnecessary files are deleted from the first magnetic tape 13 with a single instruction.

〔The invention's effect〕

As described above, the present invention recognizes a plurality of files stored on a magnetic tape as a unit of one physical block by recognizing the contents sandwiched by gaps as a unit of one physical block, thereby changing the order of the files. File operations such as deletion of a certain file can be performed without depending on the logical file format, and there is an effect that a change in the file order of a multi-file / volume format magnetic tape can be executed with a simple instruction. Also, since the logical configuration of the file is not recognized, even if a file format that does not exist will appear in the future, the present apparatus has an advantage that it can operate effectively without any change.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of the configuration of the present invention, FIG. 2 is a block diagram of an embodiment of the present invention, FIG. 3 is an explanatory diagram of the contents of a multi-file volume type magnetic tape, and FIG. FIG. 5 is a flowchart of another processing example of the central processing unit 10, and FIG. 6 is an operation explanatory diagram of the embodiment of the present invention. In the figure, 1,14... First magnetic tape device, 2,13.
First magnetic tape, 3... Input means, 4, 17... Second magnetic tape device, 5, 16... Second magnetic tape, 6... Output means, 7. Control means, 10 central processing unit, 11 main storage device, 11a buffer area, 12
... input device, 15, 18 ... magnetic tape control device.

Claims (1)

(57) [Claims] 1. A method according to claim 1, wherein the first magnetic tape includes a heading label and a tape mark indicating the end of the file in a predetermined same format in a plurality of files / volume format. Input means for reading the contents of the sandwiched blocks and storing the read contents in the buffer area; output means for writing the blocks stored in the buffer area on a second magnetic tape in block units; Specifying means for specifying the file name of the file without specifying the format of the stored file; and the block read by the input means and stored in the buffer area is the heading label; A condition that the file name previously stored in the label in a predetermined format is equal to the file name specified by the specifying means. And discriminating means for discriminating the establishment of, when the condition is judged to be satisfied by said discrimination means,
After the block of the heading label read by the input unit and stored in the buffer area is written to the second magnetic tape by the output unit, the block up to the last tape mark of the file having the file name is written. From the first magnetic tape by the input means.
And a control means for reading the blocks and writing the blocks to the second magnetic tape one block at a time by the output means.