User-Level Control of SCSI Devices

User-Level Control of SCSI Devices

IRIX contains a special kernel-level device driver whose purpose is to give user-level processes the ability to issue commands and read and write data on the SCSI bus. By using ioctl() calls to this driver, a user-level process can interrogate and program devices, and can initiate DMA transfers between memory buffers and devices.

The low-level programming used with the dsreq device driver is eased by the use of a library of utility functions documented in the dslib(3) reference page.

For more details on user-level SCSI access, see Chapter 5, "User-Level Access to SCSI Devices."