User's Guide

Chapter 3 Emulated DLT7000 SCSI Commands
Write Filemarks (10h)
278 Quantum DX-Series Software Interface Guide
The WRITE FILEMARKS command may be used to force the tape drive
to write any buffered WRITE data to the tape medium. If the tape drive is
in buffered mode, and WRITE FILEMARKS is received, the requested
filemarks are appended to the data and the WRITE buffer contents are
flushed to tape medium. A value of 0 in the Number of Filemarks field
indicates that no filemarks are to be written to the tape medium, but still
flushes any WRITE data to the tape medium.
If End of Tape (EOT) is detected while writing filemarks, the tape drive
finishes writing any buffered data and terminates with CHECK
CONDITION status. Within the Sense data, the End of Medium (EOM)
bit is set, the Sense Key field is set to NO SENSE and the Additional Sense
Code and Additional Sense Code Qualifier fields are set to EOM/P
DETECTED. The tape drive attempts to complete any subsequent WRITE
FILEMARKS, returning a CHECK CONDITION status in each case. If the
tape drive encounters the physical EOM when attempting a WRITE
FILEMARKS, it returns CHECK CONDITION status.
Immed Immediate. When this bit is set to 1, the tape drive
returns status as soon as the Command Descriptor
Block (CDB) has been validated, unless the Filemark
count is 0, or greater than 1 (since either condition
causes the WRITE buffer to be flushed to tape
medium).
When set to 0, this bit indicates the status will not be
returned until the operation is complete.
Tech Tip: The immed bit is accepted, but ignored in
processing.
Number of
Filemarks
This field contains the number of consecutive
Filemarks to be written to tape medium. A value of
0 is not considered to be an error; GOOD status is
returned.
Field Name Description