static void Main()
{
const string dir = @"C:\test";
if (!Directory.Exists(dir))
{
Directory.CreateDirectory(dir);
}
System.Security.AccessControl.DirectorySecurity ds = Directory.GetAccessControl(dir);
ds.AddAccessRule(new FileSystemAccessRule("Guest", FileSystemRights.Read, AccessControlType.Allow));
Directory.SetAccessControl(dir, ds);
Console.WriteLine(ds.GetSecurityDescriptorSddlForm(AccessControlSections.All));
}
