These operations are controlled through use of ioctl calls. The information returned includes the disk's model identification, the disk interface type, and the disk's sector size. Exclusive access is required for some special operations, such as media reformatting, and may be desirable in other circumstances. The value one specifies that exclusive access is requested. The value zero specifies the exclusive access should be released.
Exclusive access causes other open requests to fail.
Required permission is denied for the the device or operation. For other calls, this indicates the specified address is out of range or the device can no longer be accessed. This is because it may be possible for some files to have private buffers in some systems. Removal of disk media containing mounted file systems is likely to result in file system errors and system panics. Whole disk is section 0.