61
Chapter 4
[out] Long pointer to a buffer that receives the output data for the opera-
tion. 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.
Examples
#define IOCTL_WDT_ENABLE
CTL_CODE(FILE_DEVICE_UNKNOWN, 0x900,
METHOD_BUFFERED, FILE_ANY_ACCESS)
#define IOCTL_WDT_DISABLE
CTL_CODE(FILE_DEVICE_UNKNOWN, 0x901,
METHOD_BUFFERED, FILE_ANY_ACCESS)
#define IOCTL_WDT_STROBE
CTL_CODE(FILE_DEVICE_UNKNOWN, 0x902,
METHOD_BUFFERED, FILE_ANY_ACCESS)
#define IOCTL_WDT_GET_TIMEOUT
CTL_CODE(FILE_DEVICE_UNKNOWN, 0x903,
METHOD_BUFFERED, FILE_ANY_ACCESS)
#define IOCTL_WDT_SET_TIMEOUT
CTL_CODE(FILE_DEVICE_UNKNOWN, 0x904,
METHOD_BUFFERED, FILE_ANY_ACCESS)