typedef struct _PERFINFO_TRACE_HEADER { union { unsigned long Marker; struct { unsigned short Version; unsigned char HeaderType; unsigned char Flags; }; }; union { unsigned long Header; WMI_TRACE_PACKET Packet; }; union { unsigned __int64 TS; LARGE_INTEGER SystemTime; }; unsigned char Data[1]; } PERFINFO_TRACE_HEADER, *PPERFINFO_TRACE_HEADER;