index (USHORT)
Used by an application to indicate on which monitor chain its monitor buffers are being registered. The accepted values for this parameter vary for each device driver. See information on the physical mouse device driver, the physical keyboard device driver and the physical parallel port device driver in the OS/2 Input/Output Device Driver Reference to determine the valid parameter value for each device driver.
Refer to the descriptions of the DosMonReg, DosMonRead, and DosMonWrite functions in the OS/2 Control Program Programming Reference for more information.