Options to the openx Subroutine

Device drivers must support eight defined extended options in their open routine.

Additional extended options to the open are also allowed, but they must not conflict with predefined open options (that is, an openx subroutine). The defined extended options are bit flags in the ext open parameter. These options can be specified singly or in combination with each other. The required ext options are defined in the /usr/include/sys/scsi.h header file and can have one of the following values:

SC_FORCED_OPEN

Does not honor device reservation-conflict status and can include a target-level device reset.

SC_RETAIN_RESERVATION

Does not release device on close and can include a logical unit number (LUN)-level device reset.

SC_DIAGNOSTIC

Enters diagnostic mode for this device.

SC_NO_RESERVE

Prevents the reservation of the device during an openx subroutine call to that device. Allows multiple hosts to share a device.

SC_SINGLE

Places the selected device in Exclusive Access mode.