EVNTCONS.H

The public symbol file NTKRPAMP.PDB for the original release of Windows 10 tells that the kernel is built with the EVNTCONS.H header at

d:\th.public.fre\internal\minwin\priv_sdk\inc

and draws from it the following type definitions:

Line Number Type
64 struct _EVENT_HEADER_EXTENDED_DATA_ITEM
140 struct _EVENT_HEADER
166 struct _EVENT_RECORD

A header named EVNTCONS.H is among the headers in the publicly available Windows Driver Kit (WDK) for Windows 10. It is there in the “um” subdirectory with many other headers for user-mode programming.