The HidP_UsageListDifference routine returns the differences between two arrays of HID usages.
NTSTATUS HidP_UsageListDifference( PUSAGE PreviousUsageList, PUSAGE CurrentUsageList, PUSAGE BreakUsageList, PUSAGE MakeUsageList, ULONG UsageListLength );
Pointer to a list of usages that the routine compares with the list of usages in CurrentUsageList.
Pointer to a list of usages that the routine compares with the list of usages in PreviousUsageList.
Pointer to a caller-allocated buffer that, on return, contains a list of the usages that are in PreviousUsageList, but not in CurrentUsageList.
Pointer to a caller-allocated buffer that, on return, contains a list of the usages that are in CurrentUsageList, but not in PreviousUsageList.
Specifies the length, in array elements, of the buffers provided at CurrentUsageList and PreviousUsageList.
HidP_UsageListDifference returns HIDP_STATUS_SUCCESS.
A user-mode application or kernel-mode driver can use this routine to compare two usage lists, for example, to determine the change in button state between two usage lists returned by two HidP_GetButtons calls.
If the input usage lists have different lengths, an application or driver should set UsageListLength to the length of the larger list.
The routine interprets a zero usage in an input usage list as a delimiter that ends the list. Any usages after a zero in a list are not processed. Unused usages in an output list are set to zero.
For more information, see HID Collections.
|Minimum supported client||Available in Windows 2000 and later versions of Windows.|
|Header||hidpi.h (include Hidpi.h)|