Defines the default characteristics associated with a specific
magnetic tape device for subsequent file operations.
The SET MAGTAPE command is valid for magnetic tape devices
mounted with foreign volumes.
Format
SET MAGTAPE device-name[:]
1 – Parameter
device-name[:]
Specifies the name of the magnetic tape device for which the
characteristics are to be set. The device must not be currently
allocated to any other user.
2 – Qualifiers
2.1 /DENSITY
/DENSITY=density-value
Specifies the default density for all write operations on the
magnetic tape device when the volume is mounted as a foreign tape
or as an unlabeled tape.
Valid density values are:
Keyword Meaning
DEFAULT Default density
800 NRZI 800 bits per inch (BPI)
1600 PE 1600 BPI
6250 GRC 6250 BPI
3480 IBM 3480 HPC 39872 BPI
3490E IBM 3480 compressed
833 DLT TK50: 833 BPI
TK50 DLT TK50: 833 BPI
TK70 DLT TK70: 1250 BPI
6250 RV80 6250 BPI EQUIVALENT
NOTE: Only the keywords above are understood by TMSCP/TUDRIVER
code prior to OpenVMS Version 7.2. The remaining keywords in this
table are supported only on Alpha and Integrity server systems.
TK85 DLT Tx85: 10625 BPI - Cmpt III - Alpha/Integrity
servers only
TK86 DLT Tx86: 10626 BPI - Cmpt III - Alpha/Integrity
servers only
TK87 DLT Tx87: 62500 BPI - Cmpt III - Alpha/Integrity
servers only
TK88 DLT Tx88: (Quantum 4000) - Cmpt IV - Alpha/Integrity
servers only
TK89 DLT Tx89: (Quantum 7000) - Cmpt IV - Alpha/Integrity
servers only
QIC All QIC drives are drive-settable only -
Alpha/Integrity servers only
8200 Exa-Byte 8200 - Alpha/Integrity servers only
8500 Exa-Byte 8500 - Alpha/Integrity servers only
DDS1 Digital Data Storage 1 - 2G - Alpha/Integrity servers
only
DDS2 Digital Data Storage 2 - 4G - Alpha/Integrity servers
only
DDS3 Digital Data Storage 3 - 8-10G - Alpha/Integrity
servers only
DDS4 Digital Data Storage 4 - Alpha/Integrity servers only
AIT1 Sony Advanced Intelligent Tape 1 - Alpha/Integrity
servers only
AIT2 Sony Advanced Intelligent Tape 2 - Alpha/Integrity
servers only
AIT3 Sony Advanced Intelligent Tape 3 - Alpha/Integrity
servers only
AIT4 Sony Advanced Intelligent Tape 4 - Alpha/Integrity
servers only
DLT8000 DLT 8000 - Alpha/Integrity servers only
8900 Exabyte 8900 - Alpha/Integrity servers only
SDLT SuperDLT1 - Alpha/Integrity servers only
SDLT320 SuperDLT320 - Alpha/Integrity servers only
Note that tape density keywords cannot be abbreviated.
2.2 /END_OF_FILE
Writes a tape mark at the current position on the magnetic tape
volume.
2.3 /FAST_SKIP
/FAST_SKIP=option
Requires PHY_IO privilege.
Allows you to skip by file mark or by record.
NOTE
This tape positioning qualifier is for use on local SCSI
tape drives only.
PER_IO Allows a local MK device to use the skip-by-
(default) filemarks function. The tape drive must be able
to do a SCSI READ POSITION command and report
blank check at end-of-data. The IO$M_ALLOWFAST
function modifier must be supplied with IO$_
SKIPFILE. Otherwise, the tape will skip files
using the skip-by-records function.
ALWAYS Allows a local MK device to use the skip-by-
filemarks function. The tape drive must be able
to support the skip-by-filemarks function, and
no modifications should be needed to the IO$_
SKIPFILE function.
NEVER Specifies that a local MK device skip only by
records. If you use a utility that depends on the
semantics of skipping with skip-records, you may
also need to use this option because it causes
BACKUP or COPY to use the previous positioning.
2.4 /LOG
/LOG
/NOLOG
Displays information about the operations performed on the
magnetic tape volume.
2.5 /LOGSOFT
/LOGSOFT (default)
/NOLOGSOFT
Controls whether soft errors on the specified device are to be
logged in the error log file. Soft errors are errors corrected
by the hardware without software intervention. This qualifier
affects only devices that support hardware error correction, such
as the TU78 magnetic tape drive. When used with other devices,
this qualifier has no effect.
2.6 /MEDIA_FORMAT
/MEDIA_FORMAT=[NO]COMPACTION
Controls whether data records are automatically compacted and
blocked together on a TA90E tape drive. Data compaction and
record blocking increase the amount of data that can be stored
on a single tape cartridge.
Note that once data compaction or noncompaction has been selected
for a given cartridge, that same status applies to the entire
cartridge.
2.7 /RETENSION
Moves a TZK10 tape cartridge to the end of the tape, and then
back to the beginning of the tape. Use the /RETENSION qualifier
on a regular basis to help maintain the integrity of TZK10 tape
cartridges.
The /RETENSION qualifier must be used in conjunction with the
/REWIND or /UNLOAD qualifier. The /RETENSION qualifier completes
its action before /REWIND or /UNLOAD. Use /RETENSION/REWIND when
you want the tape cartridge to remain loaded in the drive. Use
/RETENSION/UNLOAD when you want to unload the tape cartridge
after the retension operation.
This qualifier only affects TZK10 tape cartridge drives and has
no effect on non-SCSI drives.
2.8 /REWIND
Requests that the volume on the specified device be rewound to
the beginning of the magnetic tape.
2.9 /SKIP
/SKIP=option
Requests that the magnetic tape volume be positioned according to
any of the following options:
BLOCK:n Skips the specified number of blocks.
END_OF_TAPE Positions the volume at the end-of-tape (EOT)
mark.
FILES:n Skips the specified number of tape marks (not
files).
The tape is positioned just past the nth tape
mark. If n is negative, the tape is still
positioned after the nth tape mark, not before
it. If the tape is already positioned immediately
after a tape mark, a skip of -1 results in no
net movement. (The tape moves to the preceding
mark, but is then repositioned to the end of the
mark, where it began.) For more information on
tape marks and files, see the HP OpenVMS System
Manager's Manual.
RECORD:n Skips the specified number of records up to
32767.
2.10 /UNLOAD
Requests that the volume on the specified device be rewound and
unloaded.
3 – Examples
1.$ MOUNT MTB1:/FOREIGN
$ SET MAGTAPE MTB1: /DENSITY=800
The MOUNT command in this example mounts a foreign tape on the
device MTB1. The SET MAGTAPE command defines the density for
writing the magnetic tape at 800 bpi.
2.$ MOUNT MTA0:/FOREIGN
$ SET MAGTAPE MTA0:/SKIP=FILES:4
The MOUNT command in this example mounts a foreign tape on the
device MTA0; the SET MAGTAPE command directs the magnetic tape
position to skip four files.