Lucent Technologies USS-720 manual Ioctlcancelpiperequest, 4 I/O Control Codes continued, February

USS-720	Preliminary User Guide, Rev. 2
USB Device Driver	February 1999

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:

Value	Description
BULK_OUT_PIPE	Bulk Out pipe.
BULK_IN_PIPE	Bulk In pipe.
INTERRUPT_PIPE	Interrupt pipe.

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.

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