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Commands: Write Filemarks (10h) Page 167

WRITE FILEMARKS (10h)

The WRITE FILEMARKS command causes the specified number of filemarks or

setmarks to be written to tape.

This command can be used to force all remaining buffered data blocks to be written

to tape without appending filemarks by specifying zero filemarks. When zero

filemarks are specified, the command does not return Good Status to the Initiator

until all buffered data blocks and filemarks are written correctly on the tape.

Otherwise, status is returned immediately.

WRITE FILEMARKS Command Descriptor Block

The following table shows the layout of the Command Descriptor Block.

Byte

Bits

7 6 5 4 3 2 1 0

0 0 0 0 1 0 0 0 0

1 0 0 0 0 0 0 WSMK IMMED

2 MSB—Number of Filemarks/Setmarks

3 Number of Filemarks/Setmarks

4 Number of Filemarks/Setmarks—LSB

5 vendor unique* 0 0 0 0 Flag Link

* This vendor-unique field is reserved and must be set to zero.

Command Descriptor Block Field Description

The following table defines the fields in the CDB.

Field

Name

Bytes

Bits

Description

WSMK bit 1 1 If this bit is 0, bytes 2-4 specify the number of filemarks to be written. If

this bit is 1, bytes 2-4 specify the number of setmarks to be written.

IMMED 1 0 If the IMMED bit is 1, status is returned as soon as the CDB has been

validated.

Note: IMMED of 1 is only valid if the drive is in buffered mode. If the

IMMED bit is 0, status is not returned until the write operation has

completed and all buffered data written to the medium.

Number of

Filemarks/

Setmarks

2-4 0-7 These fields specify the number of filemarks or setmarks to record.

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Quantum DAT 24 Drive Betriebsanweisung Seite 179