7-16 Lucent Technologies Inc.
USS-720 Preliminary User Guide, Rev. 2
USB Device Driver February 1999
13
4 I/O Control Codes (continued)
4.7 IOCTL_CANCEL_PIPE_REQUEST
IOCTL_CANCEL_PIPE_REQUEST cancels the current request on the specified pipe by flushing the pipe and
canceling any outstanding requests on the pipe. Details regarding parameters and error codes follow.
4.7.1 Parameters
lpInBuffer—Points to a buffer that contains a single byte that specifies one of the following values:
nInBufferSize—Specifies the size (in bytes) of the buffer pointed to by lpInBuffer. For this operation, this value
should be 1.
lpOutBuffer—Points to an output buffer. Not used with this operation. Set to NULL.
nOutBufferSize—Specifies the size (in bytes) of the buffer pointed to by lpOutBuffer. Not used with this operation.
Set to zero.
lpBytesReturned—Points to a DWORD that receives the actual size (in bytes) of the data stored into lpOutBuffer.
Not used with this operation.
4.7.2 Notes
None.
4.7.3 Error Codes
ERROR_INVALID_PIPE_INDEX—Specified pipe is invalid for this device instance or invalid for the current alter-
nate interface setting.
STATUS_INVALID_PARAMETER—nInBufferSize cannot be zero.
Value Description
BULK_OUT_PIPE Bulk Out pipe.
BULK_IN_PIPE Bulk In pipe.
INTERRUPT_PIPE Interrupt pipe.