Hi all I would like to get mac address from specical IP and use SendArp() of MSDN sample on my program(VC++.net). It work on WinXp(SP2) but doen't work on Win2K(SP4). It show error message "The procedure entry point freeaddrinfo could not be located in the dynamic library WS2_32.dll" , when I want to run on win2K Do I neglect or need to note any key point ? Please provide any suggestion , Thanks a lot~

Thank you very much . You provide very good instruction. Thank you...^^ hello ALL..^^

Hi Heath , Thank you for your reply . I'm sorry that I didn't have detailed description. How do I provide fixed size of buffer(memory) for code to use? If I create Image() , Can I control memory size to Image? Thank again. hello ALL..^^

Hi Christian , Thank you for your instruction. About Image image = new Image(); If I need to define fixed size of memory(dImageSize). How do I need to do? Thank again.^^ Hello All , I'm rulala.

Hi All.. I have some code in c++ and change to c# as below: uint dImageSize; byte pImage; byte pImagePtr; //statment **pImage = (byte)malloc(dImageSize);** //statment **free(m_pImage);** Any one could help me? Thank you. hello ALL..^^

Try \r\n , please. I used \n\r before , but it didn't change. I don't know the cause. hello ALL..^^

I modified it as your suggestion. It is ok . Thank you very much.:) hello ALL..^^

Hi all ,Forgive my bad english,please. I'm new user in c#.I have one problem about struct and pointer. I want to create c# API that call DLL file in c++ . //DLL sample as below(c++): struct TESTA { DWORD A; WORD B; WORD C; BYTE D[16]; }; typedef TESTA* LPTESTA; BOOL CBook::InitialButton(LPTESTA pInfo) { //statement return true; } //C# code as below: unsafe public class callDLL { [StructLayout(LayoutKind.Sequential)] public struct TESTA { public int A; public ushort B; public ushort C; [MarshalAs(UnmanagedType.ByValArray, SizeConst= 16)] public byte[] D; } [DllImport("dllname.dll")] unsafe public static extern bool InitialButton(void* pInfo); } public class Initialize_sequence { unsafe static void Main(string[] args) { callDLL.TESTA pInfo=new callDLL.TESTA(); Console.WriteLine(Marshal.SizeOf(pInfo)); callDLL.InitialButton(&pInfo); //error happen :( } } error message show "Can't get position and size of Mananged type" Any one can provide idea for me ? Thanks. hello ALL..^^