Category 09h is used to access physical partitionable hard disks. The handle used for Category 09h command is returned by the DosPhysicalDisk (Function 2) API function. (See the OS/2 Control Program Programming Reference for more information). This handle is used to tell the system which physical disk is accessed by the IOCtl command.
The Physical Disk Control commands relate to the entire partitionable hard disk. Direct track and sector I/O start at the beginning of the physical drive. PDSK_GETPHYSDEVICEPARAMS, describes the entire physical device.
The following is a summary of Category 09h IOCtl Commands:
┌───────────────┬─────────────────────────────────────────────┐ │Function │Description │ ├───────────────┼─────────────────────────────────────────────┤ │ 00h │Lock Physical Drive │ ├───────────────┼─────────────────────────────────────────────┤ │ 01h │Unlock Physical Drive │ ├───────────────┼─────────────────────────────────────────────┤ │ 44h │Write Physical Track │ ├───────────────┼─────────────────────────────────────────────┤ │ 63h │Query Physical Device Parameters │ ├───────────────┼─────────────────────────────────────────────┤ │ 64h │Read Physical Track │ ├───────────────┼─────────────────────────────────────────────┤ │ 65h │Verify Physical Track │ └───────────────┴─────────────────────────────────────────────┘