HidP_UsageAndPageListDifference (Windows CE 5.0)
This function returns the difference between two arrays of HID extended usages.
NTSTATUS HidP_UsageAndPageListDifference( PUSAGE_AND_PAGE PreviousUsageList, PUSAGE_AND_PAGE CurrentUsageList, PUSAGE_AND_PAGE BreakUsageList, PUSAGE_AND_PAGE MakeUsageList, ULONG UsageListLength);
Parameters
- PreviousUsageList
[in] Pointer to a list of usages that the function compares with the list of usages in CurrentUsageList. - CurrentUsageList
[in] Pointer to a list of usages that the function compares with the list of usages in PreviousUsageList. - BreakUsageList
[out] Pointer to a caller-allocated buffer that, on return, contains a list of the usages that are in PreviousUsageList, but not in CurrentUsageList. - MakeUsageList
[out] Pointer to a caller-allocated buffer that, on return, contains a list of the usages that are in CurrentUsageList, but not in PreviousUsageList. - UsageListLength
[in] Length, in array elements, of the buffers provided at CurrentUsageList and PreviousUsageList.
Return Values
HidP_UsageAndPageListDifference returns HIDP_STATUS_SUCCESS.
Remarks
The terms button and usage are used synonymously.
A HID client can use this function to compare two lists of extended usages, for example, to determine the change in button state between two usage lists returned by two HidP_GetButtons.
If the input usage lists have different lengths, an application or driver should set UsageListLength to the length of the larger list.
The function 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. The function sets unused usages at the end of the output lists to zero.
Requirements
OS Versions: Windows CE .NET 4.2 and later.
Header: Hidpi.h.
Link Library: Hidparse_lib.lib.
See Also
HidP_GetButtons | HidP_UsageListDifference
Send Feedback on this topic to the authors