The BLKUPD command—A scenario

This example illustrates the functions of BLKUPD. It is not meant to be used for repairing your RACF® database.

Issue the BLKUPD command on the RACF data set that you want to work with.
```
BLKUPD 'SYS1.RACF'
BLKUPD:
```

Replace a string in the block located at RBA X'E000'.

READ X'E000' UPDATE
BLKUPD:

reads the block at RBA X'E000' and specifies that changes are to be made to the block.

FORMAT

produces a formatted listing of the OLD index block obtained by the READ command.

BLOCK WITH RBA OF 00000000E000
OFFSET COMP.             ENTRY NAME                       RBA         BAM
       COUNT                                                    BLOCK BYTE BIT
 00E   000  BEATL                                   00000000DC00  00  02F   4
 02A   000  HILDE                                   00000000D000  00  02E   0
                            SEGMENT NAME: TSO       00000000D900  00  02F   1
                                          DFP       00000000DA00  00  02F   2
 051   000  HILDE.RDS.CNTL                          00000000DE00  00  02F   6
 073   000  IBMUSER                                 00000000D700  00  02E   7
 08E   000  M267                                    00000000DB00  00  02F   3
 0A6   000  M550ABC                                 00000000DD00  00  02F   5
 0C1   000  SALES                                   00000000DF00  00  02F   7
 0DA   000  SALES.* (G)                             00000000F000  00  032   0
 0F5   000  SECLABEL-SYSHIGH                        00000000D100  00  02E   1
 119   000  SECLABEL-SYSLOW                         00000000D200  00  02E   2
 13C   000  SECLABEL-SYSNONE                        00000000D300  00  02E   3
 160   000  SYSCTLG                                 00000000D600  00  02E   6
 17B   000  SYS1                                    00000000D400  00  02E   4
 193   000  VSAMDSET                                00000000D500  00  02E   5
 1AF   000  255 X'FF'S
 2BB        SEQUENCE SET POINTER                    000000000000
TOTAL NAMES IN THIS BLOCK-015. UNUSED BYTES-3358. AVERAGE NAME LENGTH-025.
LEVEL NUMBER-01. DISPLACEMENT TO LAST KEY-02BB. DISPLACEMENT TO FREE SPACE-02C4
(G) - ENTITY NAME IS GENERIC

Find the string in the old block.
```
FIND M267
IRR63002I Offset is X'0000009A'
BLKUPD:
```
locates the offset of the character string ‘M267’ in the old block.
Verify that offset X'9A' in the new block contains the character string ‘M267’ and replace that string with the character string ‘M270’.
```
REP M270 OFFSET(X'9A') VER(M267)
 IRR63004I REPLACE complete.
```

List the modified area of the new block (8 bytes beginning at offset X'9A').

LIST NEW RANGE(X'9A',8)00000000E000
  009A D4F2F7F0 01010000
  *M270....                        *

Delete the first entry in the index block.

BLKUPD:
DISPLAY
 OFFSET COMP.       ENTRY NAME                                      RBA
        COUNT
  00E    000    SIVLE                                          00000000DC00
DELETE

deletes the index entry just displayed. The next entry, which moves up to replace the deleted one, is displayed.

IRR63036I The first index entry has been deleted. The rest of the index
block may need to be updated.
   00E    000    HILDE                                        00000000D000
                                          SEGMENT NAME: TSO   00000000D900
                                                        DFP   00000000DA00

Insert a new first index entry.

INSERT ENTRY(SIVLE) CLASS(USER) RBA(X'DC00')

inserts a new index entry, with the specified name, and RBA immediately preceding the entry just displayed. The new entry is displayed.

IRR63038I The first index entry has been inserted. The rest of the index
block may need to be updated.
   00E    000    SIVLE                                        00000000DC00
NEXT

displays the next index entry.

00E    000    HILDE                                        00000000D000
                                       SEGMENT NAME: TSO   00000000D900
                                                     DFP   00000000DA00

Change the name of the entry.

04C  000    HILDE.RDS.CNTL                                 00000000DE00
CHANGE ENTRY(HILDE.RDS.CHNG) CLASS(DATASET)

changes the entry name of the entry.

04C  000    HILDE.RDS.CHNG                                    00000000DE00

Save the changes you have made and obtain a listing of your updated block.

END SAVE

ends the DISPLAY command and saves the changes that were made in the index block. The utility still runs under the READ subcommand.

IRR63009I DISPLAY ended. Changes saved.

FORMAT NEW

produces a formatted listing of the updated index block.

BLOCK WITH RBA OF 00000000E000
OFFSET COMP.             ENTRY NAME                       RBA         BAM
       COUNT                                                    BLOCK BYTE BIT
 00E   000  SIVLE                                   00000000DC00  00  02F   4
 025   000  HILDE                                   00000000D000  00  02E   0
                            SEGMENT NAME: TSO       00000000D900  00  02F   1
                                          DFP       00000000DA00  00  02F   2
 04C   000  HILDE.RDS.CHNG                          00000000DE00  00  02F   6
 06E   000  IBMUSER                                 00000000D700  00  02E   7
 089   000  M270                                    00000000DB00  00  02F   3
 0A1   000  M550ABC                                 00000000DD00  00  02F   5
 0BC   000  SALES                                   00000000DF00  00  02F   7
 0D5   000  SALES.* (G)                             00000000F000  00  032   0
 0F0   000  SECLABEL-SYSHIGH                        00000000D100  00  02E   1
 114   000  SECLABEL-SYSLOW                         00000000D200  00  02E   2
 137   000  SECLABEL-SYSNONE                        00000000D300  00  02E   3
 15B   000  SYSCTLG                                 00000000D600  00  02E   6
 176   000  SYS1                                    00000000D400  00  02E   4
 18E   000  VSAMDSET                                00000000D500  00  02E   5
 1AA   000  255 X'FF'S
 2B6        SEQUENCE SET POINTER                    000000000000
TOTAL NAMES IN THIS BLOCK-015. UNUSED BYTES-3363. AVERAGE NAME LENGTH-024.
LEVEL NUMBER-01. DISPLACEMENT TO LAST KEY-02B6. DISPLACEMENT TO FREE SPACE-02BF
(G) - ENTITY NAME IS GENERIC

Save the changes made and write them back to the RACF database.
```
END SAVE
IRR63013I READ ended. Block saved.
```
ends the READ command and writes the new block out to the RACF database.

Locate the block that contains the generic name of SALES.*.

LOCATE ENTRY(SALES.*) CLASS(DATASET) GENERIC

displays a formatted list of the level one block that contains the generic entry name ‘SALES.*’.

BLOCK WITH RBA OF 00000000E000
OFFSET COMP.             ENTRY NAME                       RBA         BAM
       COUNT                                                    BLOCK BYTE BIT
 00E   000  SIVLE                                   00000000DC00  00  02F   4
 025   000  HILDE                                   00000000D000  00  02E   0
                            SEGMENT NAME: TSO       00000000D900  00  02F   1
                                          DFP       00000000DA00  00  02F   2
 04C   000  HILDE.RDS.CHNG                          00000000DE00  00  02F   6
 06E   000  IBMUSER                                 00000000D700  00  02E   7
 089   000  M270                                    00000000DB00  00  02F   3
 0A1   000  M550ABC                                 00000000DD00  00  02F   5
 0BC   000  SALES                                   00000000DF00  00  02F   7
 0D5   000  SALES.* (G)                             00000000F000  00  032   0
 0F0   000  SECLABEL-SYSHIGH                        00000000D100  00  02E   1
 114   000  SECLABEL-SYSLOW                         00000000D200  00  02E   2
 137   000  SECLABEL-SYSNONE                        00000000D300  00  02E   3
 15B   000  SYSCTLG                                 00000000D600  00  02E   6
 176   000  SYS1                                    00000000D400  00  02E   4
 18E   000  VSAMDSET                                00000000D500  00  02E   5
 1AA   000  255 X'FF'S
 2B6        SEQUENCE SET POINTER                    000000000000
TOTAL NAMES IN THIS BLOCK-015. UNUSED BYTES-3363. AVERAGE NAME LENGTH-024.
LEVEL NUMBER-01. DISPLACEMENT TO LAST KEY-02B6. DISPLACEMENT TO FREE SPACE-02BF
(G) - ENTITY NAME IS GENERIC

End the BLKUPD session.
```
BLKUPD:
END
READY
```
terminates the BLKUPD command.