internal DirMonCompletion(DirectoryMonitor dirMon, string dir, bool watchSubtree, uint notifyFilter)
{
this._dirMon = dirMon;
NativeFileChangeNotification notification = new NativeFileChangeNotification(this.OnFileChange);
this._rootCallback = GCHandle.Alloc(notification);
int hr = UnsafeNativeMethods.DirMonOpen(dir, HttpRuntime.AppDomainAppIdInternal, watchSubtree, notifyFilter, notification, out this._ndirMonCompletionPtr);
if (hr != 0)
{
this._rootCallback.Free();
throw FileChangesMonitor.CreateFileMonitoringException(hr, dir);
}
this._ndirMonCompletionHandle = new HandleRef(this, this._ndirMonCompletionPtr);
Interlocked.Increment(ref _activeDirMonCompletions);
}