ioctl

Establish conditional modules for each I/O control command.

Syntax:

#include "sys/scsi.h"

int
xxioctl(dev, cmd, arg, mode)
dev_t dev;
int cmd, mode;
caddr_t arg;

The logic is as follows:

1. Call scsi_getdev(D3osdi) to ensure that the dev argument is for a legitimate device. If not, set u.u_error to ENODEV and return. Then check that the device is present. If not, set u.u_error to ENODEV and return.

2. Provide for any other ioctls to fit your needs. If an improper command is specified, set u.u_error to EINVAL and return.