using System;

using System.Runtime.InteropServices;
 
 
namespace Test
{
  using DWORD = System.UInt32;
  using PSECURITY_DESCRIPTOR = System.IntPtr;
  public class Security
  {
    enum SECURITY_INFORMATION  : int
    {
      DACL_SECURITY_INFORMATION = 4, 
    }
 
    [DllImport("advapi32.dll", SetLastError=true)]
      [return: MarshalAs(UnmanagedType.Bool)]
     static extern bool GetFileSecurity(
       string lpszUsername,
       SECURITY_INFORMATION info,
       PSECURITY_DESCRIPTOR descriptor,
       DWORD val2,
       out uint length);
 
    [DllImport("advapi32.dll", SetLastError=true)]
      [return: MarshalAs(UnmanagedType.Bool)]
    static extern bool SetFileSecurity(string lpszUsername,
      SECURITY_INFORMATION info, PSECURITY_DESCRIPTOR descriptor);
 
    static public void CopyFileSecurity(string fileName,
                                         string targetFileName)
    {
      uint dwLength = 0;                
      bool result = GetFileSecurity(fileName, 
      SECURITY_INFORMATION.DACL_SECURITY_INFORMATION,
      IntPtr.Zero, 0, out dwLength);
      int lastError = Marshal.GetLastWin32Error() ;
 
      //Console.WriteLine(string.Format("Last Error = {0}", lastError)); 
 
      if ( ( result || lastError == 0x7a) && dwLength > 0)
      {
        PSECURITY_DESCRIPTOR pSecurityDescriptor = 
        System.Runtime.InteropServices.Marshal.
          AllocHGlobal((int) dwLength);
        if (GetFileSecurity(fileName,
          SECURITY_INFORMATION.DACL_SECURITY_INFORMATION, 
          pSecurityDescriptor, dwLength, out dwLength))
        {
          SetFileSecurity(targetFileName,
            SECURITY_INFORMATION.DACL_SECURITY_INFORMATION,
            pSecurityDescriptor);
        }
        System.Runtime.InteropServices.Marshal.FreeHGlobal
   (pSecurityDescriptor);
      }
    }
  }
}