Provide a common access method for optical disks


driver ... optical disk_options ... &

Runs on:

QNX Neutrino


One of the devb-* drivers.

The optical options control the driver's interface to If specified, they must follow the optical keyword:

Specify the device prefix (default: mo).
Don't use the geometry from BIOS int 13. By default, if you don't specify the translation option, the BIOS geometry is used.
Don't use the geometry from the partition table. The geometry from the partition table is used if you specify the nobios option, or the BIOS geometry is invalid.
Set the maximum number of command retries on the specified path, target, and Logical Unit Number (LUN). The default is 10.
Set/clear the device as removable on path N, target N, and LUN N.
Set the rw and group command timeouts on path N, target N, and LUN N. The defaults are the values from the Timeout and Protect mode page if supported, otherwise 60:90:10:10 (in seconds).
Specify the geometry explicitly; this overrides the geometry from the BIOS and the partition table. The arguments are:
  • heads and sectors — report this many heads (and optionally, sectors) to for hard disks (default is 64 heads and 32 sectors). The QNX 4 filesystem doesn't need this information for normal operation. It's needed only to let fdisk write the correct boot cylinder for booting.
  • path_ID — the number of the controller to use, where the first controller is 0 (the default).
  • target — for IDE, this is the master (0) or slave (1); for SCSI, it's the SCSI ID the device is jumpered for. The default is 0.
  • lun — the Logical Unit Number for SCSI; not needed for IDE. The default is 0.
Set the verbosity level on path N, target N, and LUN N.


The provides common access methods (CAMs) for optical disk devices.