>>These functions are only available if fltLib.dll
>is present on the operating system.
Isn’t it always present together with FltMgr.sys?
Yes. My answer assumed that OP wanted to do it from user mode,
hence not fltmgr.sys, but fltlib.dll. If the question was
meant about kernel mode, then FltEnumerateFilter and/or
FltEnumerateFilterInformation are the functions to use.
L.