WDU_StreamOpen()

DWORD DLLCALLCONV WDU_StreamOpen	(	_In_ WDU_DEVICE_HANDLE	hDevice,
		_In_ DWORD	dwPipeNum,
		_In_ DWORD	dwBufferSize,
		_In_ DWORD	dwRxSize,
		_In_ BOOL	fBlocking,
		_In_ DWORD	dwOptions,
		_In_ DWORD	dwRxTxTimeout,
		_Outptr_ WDU_STREAM_HANDLE *	phStream
	)

Opens a new data stream for the specified pipe.

Note

The streaming functions are currently supported only on Windows. A stream can be associated with any pipe except the control pipe (Pipe 0). The stream's data transfer direction – read/write – is derived from the direction of its pipe.

Parameters

[in]	hDevice	A unique identifier for the device/interface.
[in]	dwPipeNum	The number of the pipe for which to open the stream
[in]	dwBufferSize	The size, in bytes, of the stream's data buffer.
[in]	dwRxSize	The size, in bytes, of the data blocks that the stream reads from the device. This parameter is relevant only for read streams and must be <= dwBufferSize.
[in]	fBlocking	TRUE for a blocking stream (performs blocking I/O); FALSE for a non-blocking stream (non-blocking I/O).
[in]	dwOptions	Can be a bit-mask of any of the following options: USB_ISOCH_NOASAP - For isochronous data transfers. Setting this option instructs the lower driver (usbd.sys) to use a preset frame number (instead of the next available frame) while performing the data transfer. Use this flag if you notice unused frames during the transfer, on low-speed or full-speed devices (USB 1.1 only) and only on Windows. USB_ISOCH_RESET - Resets the isochronous pipe before the data transfer. It also resets the pipe after minor errors, consequently allowing the transfer to continue. USB_ISOCH_FULL_PACKETS_ONLY - When set, do not transfer less than packet size on isochronous pipes. USB_BULK_INT_URB_SIZE_OVERRIDE_128K - Limits the size of the USB Request Block (URB) to 128KB. USB_STREAM_OVERWRITE_BUFFER_WHEN_FULL - When there is not enough free space in a read stream's data buffer to complete the transfer, overwrite old data in the buffer. (Applicable only to read streams).
[in]	dwRxTxTimeout	Maximum time, in milliseconds, for the completion of a data transfer between the stream and the device. Zero = infinite wait.
[out]	phStream	Pointer to a unique identifier for the stream, to be returned by the function and passed to the other WDU_StreamXXX() functions.

Returns

WinDriver Error Code

 
DWORD dwStatus;
DWORD dwPipeNum, dwSize, dwBytesTransferred, cmd = MENU_RW_READ_PIPE;
VOID *pBuffer = NULL;
WDU_STREAM_HANDLE stream;
DWORD dwBufferSize = 0x20000;
 
dwStatus = WDU_StreamOpen(hDevice, dwPipeNum, dwBufferSize,
                    dwSize, TRUE, 0, TRANSFER_TIMEOUT, &stream);
if (dwStatus)
{
    ERR("ReadWritePipesMenu: WDU_StreamOpen() failed. "
        "error 0x%lx (\"%s\")\n", dwStatus, Stat2Str(dwStatus));
    goto End_transfer;
}
 
dwStatus = WDU_StreamStart(stream);
if (dwStatus)
{
    ERR("ReadWritePipesMenu: WDU_StreamStart() failed. error "
        "0x%lx (\"%s\")\n", dwStatus, Stat2Str(dwStatus));
    goto End_transfer;
}
 
if (cmd == MENU_RW_READ_PIPE)
{
    dwStatus = WDU_StreamRead(stream, pBuffer, dwSize,
        &dwBytesTransferred);
}
else
{
    dwStatus = WDU_StreamWrite(stream, pBuffer, dwSize,
        &dwBytesTransferred);
}
if (dwStatus)
{
    BOOL fIsRunning;
    DWORD dwLastError;
    DWORD dwBytesInBuffer;
 
    dwStatus = WDU_StreamGetStatus(stream, &fIsRunning,
        &dwLastError, &dwBytesInBuffer);
    if (!dwStatus)
        dwStatus = dwLastError;
}
 
WDU_StreamClose(stream);