TCTL, MT(1,C)               AIX Commands Reference                TCTL, MT(1,C)



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tctl, mt



PURPOSE

Gives commands to streaming tape.

SYNTAX


        +--- -f$TAPE ---+            +--- 1 ---+
tctl ---|               |-- subcmd --|         |---|
        +- -f tapename -+            +- count -+


DESCRIPTION

The tctl command gives subcommands to a streaming tape device.  If you do not
specify the -f flag with tapename, the environment variable TAPE is used.  If
the environment variable does not exist, tctl uses the device /dev/rmt4.  The
tapename parameter must be a raw (not block) tape device.  You can specify more
than one operation with count.  The mt command is a synonym for the tctl
command.

Note:  To specify a PS/2 internal tape backup unit with the tctl command, use
       the -f option and specify the norewind device.  Superuser authority is
       required to use the erase, eof, or weof tctl operations.  The ras1 and
       ras2 subcommands are not supported on the internal tape backup unit.
       The erase subcommand erases only the first 29K of user data and filemark
       map.  The following example rewinds a PS/2 internal tape backup unit:

         tctl -f /dev/rst4 rewind

PARAMETERS

eof         Writes count end-of-file markers at the current position on the
            tape.

weof        Writes count end-of-file markers at the current position on the
            tape.

fsf         Moves the tape forward count files.

fsr         Moves the tape forward count records.

bsf         Moves the tape backward count files if the device has backspace
            capability.






Processed November 8, 1990       TCTL, MT(1,C)                                1

TCTL, MT(1,C)               AIX Commands Reference                TCTL, MT(1,C)



bsr         Moves the tape backward count records if the device has backspace
            capability.

rewind      Rewinds the tape.  The count parameter is ignored.

            Note:  It is sometimes necessary to issue a reset before issuing a
                   rewind subcommand.

offline     Places the tape drive off-line.  The count parameter is ignored.

rewoffl     Places the tape drive off-line.  The count parameter is ignored.

reset       Makes the tape drive ready for either read or write access.  The
            count parameter is ignored.

erase       Erases all contents on the tape and rewinds it.

retension   Moves the tape to the beginning, the end, and back to the beginning
            of the tape.  If you have excessive read errors during a restore
            operation, you should run the retension subcommand.  If the tape
            has been exposed to environmental extremes, you should run the
            retension subcommand before the save operation.

            Note:  This subcommand is available on a PS/2 only.

ras1        Performs a checksum on the tape drive.

ras2        Checks the capstan speed, verifies the operations of the BOT, EOT,
            and SAFE sensors, and writes a worst case pattern on the tape and
            attempts to verify the pattern.

status      Prints status information about the tape unit.

FILES

/dev/rmt??  The raw streaming tape interface.

RELATED INFORMATION

See the following command:  "dd."

See the ioctl system call and the tape and environ files in AIX Operating
System Technical Reference.












Processed November 8, 1990       TCTL, MT(1,C)                                2