Microsoft.Win32.UnsafeNativeMethods.ManifestEtw.EventRegister C# (CSharp) Method

            internal static unsafe uint EventRegister(
                        [In] ref Guid providerId,
                        [In]EtwEnableCallback enableCallback,
                        [In]void* callbackContext,
                        [In][Out]ref long registrationHandle
                        )
            {
                Interop.Kernel32.EtwEnableCallback indirection = delegate(ref Guid sourceId,
                                                                         int isEnabled,
                                                                         byte level,
                                                                         ulong matchAnyKeywords,
                                                                         ulong matchAllKeywords,
                                                                         Interop.Kernel32.EVENT_FILTER_DESCRIPTOR* filterData,
                                                                         IntPtr cbContext)
                {
                    enableCallback(ref sourceId,
                                   isEnabled,
                                   level,
                                   (long)matchAnyKeywords,
                                   (long)matchAllKeywords,
                                   (EVENT_FILTER_DESCRIPTOR*)filterData,
                                   (void*)cbContext);
                };
                ulong temp;
                uint status = Interop.Kernel32.EventRegister(ref providerId, indirection, (IntPtr)callbackContext, out temp);
                registrationHandle = (long)temp;
                
                return status;
            }