Appendix D Watchdog Timer Programming on WinCE
TPC-2012 User Manual D-2 ni.com
can use these control codes with DeviceIoControl to perform
driver-specific functions.
•lpInBuffer
(in) Long pointer to a buffer that contains the data required to perform
the operation. This parameter can be NULL if the dwIoControlCode
parameter specifies an operation that does not require input data.
•nInBufferSize
(in) Size, in bytes, of the buffer pointed to by lpInBuffer.
•lpOutBuffer
(out) Long pointer to a buffer that receives the operation’s output data.
This parameter can be NULL if the dwIoControlCode parameter
specifies an operation that does not produce output data.
•nOutBufferSize
(in) Size, in bytes, of the buffer pointed to by lpOutBuffer.
•lpBytesReturned
(out) Long pointer to a variable that receives the size, in bytes, of the
data stored into the buffer pointed to by lpOutBuffer. The
lpBytesReturned parameter cannot be NULL. Even when an
operation produces no output data, and lpOutBuffer can be
NULL,D eviceIoControl makes use of the variable pointed to by
lpBytesReturned. After such an operation, the variable value has no
meaning.
•lpOverlapped
(in) Ignored; set to NULL.
• Return Values
Nonzero indicates success. Zero indicates failure. To get extended
error information, call GetLastError.