SCSI Primary Commands - 5 (SPC-5 r19)

The SCSI command set is designed to provide efficient peer-to-peer operation of SCSI devices (e.g., disks, tapes, media changers) by an operating system. The SCSI command set assumes an underlying command-response protocol.
The SCSI command set provides multiple operating systems concurrent control over one or more SCSI devices. However, proper coordination of activities between the multiple operating systems is critical to avoid data corruption. Commands that assist with coordination between multiple operating systems are described in this standard. However, details of the coordination are beyond the scope of the SCSI command set.
This standard defines the device model for all SCSI devices. This standard defines the SCSI commands that are basic to every device model and the SCSI commands that may apply to any device model.