# System.IO

``` diff
 namespace System.IO {
     public class FileStream : Stream {
+        public FileStream(string path, FileStreamOptions options);
     }
+    public sealed class FileStreamOptions {
+        public FileStreamOptions();
+        public FileAccess Access { get; set; }
+        public FileMode Mode { get; set; }
+        public FileOptions Options { get; set; }
+        public long PreallocationSize { get; set; }
+        public FileShare Share { get; set; }
+    }
 }
```

