+ if (null == fileSecurity)
+ throw new ArgumentNullException ("fileSecurity");
+
+ fileSecurity.PersistModifications (SafeFileHandle);
+ }
+#endif
+
+#if NET_4_5
+ public override Task FlushAsync (CancellationToken cancellationToken)
+ {
+ return base.FlushAsync (cancellationToken);
+ }
+
+ public override Task<int> ReadAsync (byte[] buffer, int offset, int count, CancellationToken cancellationToken)
+ {
+ return base.ReadAsync (buffer, offset, count, cancellationToken);
+ }
+
+ public override Task WriteAsync (byte[] buffer, int offset, int count, CancellationToken cancellationToken)
+ {
+ return base.WriteAsync (buffer, offset, count, cancellationToken);