Using the SC_NO_RESERVE Option

The SC_NO_RESERVE option causes the SCSI device driver not to issue the SCSI reserve command during the opening of the device and not to issue the SCSI release command during the close of the device. This allows multiple hosts to share the device.

The SCSI device driver should require the caller to have appropriate authority to request the SC_NO_RESERVE option, because this request allows other hosts to modify data on the device. If a caller does this kind of request then the caller must ensure data integrity between multiple hosts. If the caller attempts to initiate this system call without the proper authority, the SCSI device driver should return a value of -1, with the errno global variable set to a value of EPERM.