The IOCTL_PAR_GET_DEVICE_CAPS request does the following:
Specifies the protocols that the system-supplied bus driver for parallel ports must not use with a parallel device
Returns the operating protocols that the parallel device supports
The AssociatedIrp.SystemBuffer member points to a USHORT buffer that the client allocates to input and output mode information. The request sets the input buffer to a bitwise OR of the modes that the parallel port bus driver must not use with a parallel device.
Input Buffer Length
The length of a USHORT.
AssociatedIrp.SystemBuffer points to the USHORT buffer that the parallel port bus driver uses to output mode information. The parallel port bus driver sets the buffer to indicate which operating protocols the parallel device supports.
Output Buffer Length
The Parameters.DeviceIoControl.OutputBufferLength member is set to the size, in bytes, of a USHORT.
The Information member is set to the size, in bytes, of a USHORT.
The Status member is set to one of the generic status values returned by device control requests for parallel devices or to the following value:
|Header||ntddpar.h (include Ntddpar.h)|