Use this command to examine blocked and unblocked
tapes online. You can:
- Shift a blocked or unblocked tape forward or backward
- Search a blocked or unblocked tape for a specific item
- Display blocked or unblocked tape data blocks.
A blocked tape is a tape of physical records that can consist of
one or more contiguous logical records or parts of logical records.
Physically, the blocked tape is read one record at a time; logically, the
TPF system manages the blocked tape record by record.
An unblocked tape contains one physical record for each
block.
Requirements and Restrictions
- The ZDEBE command cannot be used when working with logical records in a
blocked tape. Use the ZDEBB command instead.
- The specified tape device must be free for use.
- The display and print tape block parameters (BD, BP, FD, FP, SD, SP, TD,
and TP) require that the TPF system is in a state where the get file storage
(GFS) facility is active (that is, CRAS state or higher). In addition,
the TPF system must not be cycling to 1052 state. For the SD and SP
parameters, the tape search takes place before checking these constraints and
displaying the tape information.
- All forward and backward tape shifting and tape search operations end
immediately if a tapemark is detected.
Format
- cuu
- is a 3-digit hexadecimal tape device address.
- BF
- shifts the blocked or unblocked tape backward to the preceding
tapemark.
- RU
- rewinds and unloads the unblocked tape.
- Note:
- The blocked or unblocked tape is unloaded regardless of whether the TPF
system is in test mode.
- RW
- rewinds the blocked or unblocked tape.
- SF
- shifts the blocked or unblocked tape forward.
- TD
- performs a tape block hexadecimal dump.
- TL
- displays the tape label.
- Note:
- This parameter positions the tape following the HDR2 label.
- TP
- prints the next tape block in character format.
- WT
- writes the tapemarks.
- Note:
- The blocked or unblocked tape must be write-enabled. You cannot
specify this parameter if the tape is at load point.
- BD
- shifts the blocked or unblocked tape backward the specified number of
blocks and performs a tape block hexadecimal dump (BS and TD).
- BP
- shifts the blocked or unblocked tape backward the specified number of
blocks and prints the tape block in character format (BS and TP).
- BS
- shifts the blocked or unblocked tape backward the specified number of
blocks.
- FD
- shifts the blocked or unblocked tape forward the specified number of
blocks and performs a tape block hexadecimal dump (SR and TD).
- FP
- shifts the blocked or unblocked tape forward the specified number of
blocks and prints the tape block in character format (SR and TP).
- SR
- shifts the blocked or unblocked tape forward the specified number of
blocks.
- SD
- searches the blocked or unblocked tape for the specified data and performs
a tape block hexadecimal dump (TS and TD)
- SP
- searches the blocked or unblocked tape for the specified data and prints
the tape block in character format (TS and TP)
- TS
- searches the blocked or unblocked tape for the specified data.
- blocks
- is the number of blocks from 0000-9999.
- displacement
- is the 3-byte hexadecimal displacement in the tape block.
- C
- indicates that the data is character data.
- X
- indicates that the data is hexadecimal data.
- -data-
- is the character or hexadecimal data.
- Note:
- You must begin and end the data with the - character.
Additional Information
- The blocked or unblocked tape is internally mounted as a DBE tape and the
tape status table (TSTB) entry remains seized for the duration of the
operation.
- Only the WT parameter is checked for file protect status.
- If an HDR1 or HDR2 label is not found, asterisks are displayed in the
related fields of the output. Similarly, asterisks are displayed in the
SSN and SSU fields if the subsystem name that is contained in the HDR1 label
is not recognized by the current system configuration.
- The display and print tape block parameters (BD, BP, FD, FP, SD, SP, TD,
and TP) process the tape as an unblocked tape. That is, each physical
block is considered one logical record.
- Hexadecimal digits are converted to printable characters when
possible. Otherwise, the hexadecimal representation of the data is
displayed.
- Only the first 4-KB of a tape block is displayed at one time.
- If a 16-byte line of data contains all X'00' characters, the line
is not displayed.
- After data is displayed, the tape is positioned before the next
block.
Examples
The tape label for the specified tape device is displayed in the following
example, where:
- VOLUME SERIAL
- is the volume serial number, which should be the same as the external
label on the unblocked tape.
- SSN
- is the name of the subsystem in which the unblocked tape was
created.
- SSU
- is the name of the subsystem user in which the unblocked tape was
created.
- F
- is the name of the data set.
- G
- is the generation number of the unblocked tape.
- S
- is the volume sequence number of the unblocked tape.
- FILE SERIAL NUMBER
- is the file serial number of the first unblocked tape in the data
set.
- CREATION DATE
- is the date the unblocked tape was created.
- EXPIRATION DATE
- is the date the unblocked tape expires and can be written over.
- BLOCKING FORMAT
- is the blocking mode, either BLK or NOBLK.
- COMPACTION MODE
- is the improved data recording capability (IDRC) mode, which can be COMP
(compaction) or NOCOMP (no compaction).
Notice that asterisks are displayed in the SSN and SSU fields. This
indicates that the subsystem name that is contained in the HDR1 label is not
recognized by the current system configuration.
+--------------------------------------------------------------------------------+
|User: ZDEBE 480 TL |
| |
|System: COTP0001I 09.59.05 DEBE - TAPE LABEL RECORD DISPLAY |
| VOLUME SERIAL -A00136- SSN-**** SSU-**** |
| F-VIRTUAL.TAPE G -0001 S -0001 |
| FILE SERIAL NUMBER - A00136 |
| CREATION DATE - 00000 BLOCKING FORMAT - NOBLK |
| EXPIRATION DATE - 00000 COMPACTION MODE - NOCOMP |
+--------------------------------------------------------------------------------+
The next tape block is displayed in the following example.
+--------------------------------------------------------------------------------+
|User: ZDEBE 482 TP |
| |
|System: COTQ0001I 12.32.58 DEBE - TAPE DATA RECORD DISPLAY |
| 000 00800000 007C0000 D G 00000000 |
| 010 A991B92C 132B1150 00000065 00000000 |
| 070 B S S H P N A991B92C 132BB150 |
| END OF DISPLAY - RECORD LENGTH IS 128 |
| ZEROED LINES SUPPRESSED |
+--------------------------------------------------------------------------------+
The unblocked tape is shifted forward 2 blocks in the following
example.
+--------------------------------------------------------------------------------+
|User: ZDEBE 482 SR 0002 |
| |
|System: COTO0044I 12.06.51 DEBE HPN COMPLETE |
+--------------------------------------------------------------------------------+
In the following example, the unblocked tape is searched for the first
block that contains the VOL1 characters.
+--------------------------------------------------------------------------------+
|User: ZDEBE 482 SD 000 C-VOL1- |
| |
|System: COTQ0001I 12.08.43 DEBE - TAPE DATA RECORD DISPLAY |
| 000 E5D6D3F1 C1F0F0F1 F4F5F040 40404040 |
| 010 40404040 40404040 40404040 40404040 |
| 020 40404040 40404040 40E5E3C1 D7C540E5 |
| 030 E2E2C940 40404040 40404040 40404040 |
| 040 40404040 40404040 40404040 40404040 |
| END OF DISPLAY - RECORD LENGTH IS 80 |
+--------------------------------------------------------------------------------+
Related Information
See ZDEBB-Display Blocked Tapes Online for more information about the ZDEBB command.