IOCTL_IEEE1284_GET_MODE IOCTL (ntddpar.h)
The IOCTL_IEEE1284_GET_MODE request returns the IEEE 1284 read and write protocols that are currently set for a parallel device. This request does not require that the parallel port, to which the parallel device is attached, be locked.
For more information, see Setting and Clearing a Communication Mode for a Parallel Device.
Major code
Input buffer
None.
Input buffer length
None.
Output buffer
The AssociatedIrp.SystemBuffer member points to a PARCLASS_NEGOTIATION_MASK structure that the client allocates to output mode information. The system-supplied bus driver for parallel ports specifies the read (reverse) protocol in the usReadMask member and the write (forward) protocol in the usWriteMask member.
Output buffer length
The Parameters.DeviceIoControl.OutputBufferLength member is set to the size, in bytes, of a PARCLASS_NEGOTIATION_MASK structure.
Status block
If the request is successful, the Information member is set to the size, in bytes, of a PARCLASS_NEGOTIATION_MASK. Otherwise, the Information member is set to zero.
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:
STATUS_BUFFER_TOO_SMALL
The value of Parameters.DeviceIoControl.OutputBufferLength is less than the size, in bytes, of a PARCLASS_NEGOTIATION_MASK structure.
Requirements
| Requirement | Value |
|---|---|
| Header | ntddpar.h (include Ntddpar.h) |