control codes can then be advertised, and an application can use these control codes with DeviceIoControl to perform driverspecific 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 parame- ter 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, the DeviceIoControl function makes use of the variable pointed to bylpBytesReturned. After such an opera- tion, the value of the variable is without meaning.
lpOverlapped
[in] Ignored; set to NULL.
Return Values
Nonzero indicates success. Zero indicates failure. To get extended error information, call GetLastError.
45 | AppendixB |