sw01 -- Storage Device Interface (SDI) WORM Target Driver


The sw01 driver is an SDI-compliant Write Once Read Many (WORM) target driver that provides access to one or more WORM drives. Each drive must be attached to a SCSI Bus that is controlled by an SDI-compliant host adapter driver.

Access to the particular drive is accomplished through the sw01 device nodes located in /dev/[r]worm.

Each device node identifies a particular drive based on the SCSI ID assigned to that drive. The binding between a device node and a WORM drive is as follows:

WORM drive with lowest SCSI ID

WORM drive with next to lowest SCSI ID
and so on.

A WORM drive uses removable media divided into consecutively numbered, fixed-size sectors that can be accessed in any order, similar to a hard disk. Most of the standard tools for reading and writing to and from a hard disk, such as dd(ADM) or read(S), work with a WORM drive. However, keep in mind that for WORM drives, each sector can be written to only once. This characteristic causes problems if a WORM device is mounted (mount(ADM)) without using the read-only flag, -r.

ioctl calls

The ioctl(S) calls supported by the sw01 driver are documented on the sdi(HW) manual page.


The following worm special files are provided for SCO Open Server Release 6.0.0. In the following table, 'C' is the controller number of the Host Adapter that the worm drive is attached to, 'B' is the bus or channel number that the worm drive is attached to and 'T' is the target ID of the worm drive. Also, 'U' is the worm drive's number in the system, starting at 0 ( zero ). For example, the first worm drive in the system could be referenced as /dev/rworm/worm0

Block Special File Character Special File

/dev/worm/cCbBtT /dev/rworm/cCbBtT

 Block Special File     Character Special File
 /dev/worm/cCbBtT       /dev/rworm/cCbBtT


ioctl(S), mount(ADM), sc01(HW), sd01(HW), sdi(HW), st01(HW)
© 2005 The SCO Group, Inc. All rights reserved.
SCO OpenServer Release 6.0.0 - 02 June 2005