C#

public delegate IntPtr SetHookDelegate(int idHook, HookProc lpfn, IntPtr hInstance, uint threadId);
      SetHookDelegate myookDelegate = null;

using (Process curProcess = Process.GetCurrentProcess())
            using (ProcessModule curModule = curProcess.MainModule)
            {
                myookDelegate = new SetHookDelegate(Win32.SetWindowsHookEx);
                myookDelegate.BeginInvoke((int)Win32.HookType.WH_KEYBOARD_LL,
                HookProcedure,
                Win32.GetModuleHandle(curModule.ModuleName),
                0, new AsyncCallback(CallMeWhenFinished), myReturnValue);
            }

<br />
struct params<br />
{<br />
    char*   info;<br />
    params* next;<br />
};<br />
<br />
struct device<br />
{<br />
    unsigned int flags;<br />
    char*        name;<br />
    char*        description;<br />
    params*      p_params;<br />
    device*      next;<br />
};<br />

<br />
int get_device_list( device* dev );<br />
void free_device_list( device* dev );<br />

<br />
<br />
[StructLayout(LayoutKind.Sequential)]<br />
public class device<br />
{<br />
   [MarshalAs(UnmanagedType(UnmanagedType.U4)<br />
   uint flags;<br />
<br />
   [MarshalAs(UnmanagedType(UnmanagedType.LPStr)<br />
   string name;<br />
<br />
   [MarshalAs(UnmanagedType(UnmanagedType.LPStr)<br />
   string description;<br />
<br />
   IntPtr p_params;<br />
   IntPtr next;<br />
<br />
   public device() <br />
   {<br />
      name        = new string( '\0', 100 );<br />
      description = new string( '\0', 100 );<br />
      flsgs       = 0;<br />
      p_params    = IntPtr.Zero;<br />
      next        = IntPtr.Zero;<br />
   }<br />
<br />
}<br />
<br />
// ??????????? ?-??? ?? DLL<br />
   [Dllimport("api.dll")]<br />
   static extern int get_device_list( IntPtr device_ptr );<br />
<br />
   [Dllimport("api.dll")]<br />
   static extern int free_device_list( IntPtr device_ptr );<br />
<br />
<br />
public static void main()<br />
{<br />
    device dev;<br />
    IntPtr device_ptr = Marshal.AllocHGlobal( Sizeof( typeof( device ) ) );<br />
    Marshal.StructureToPtr( dev, device_ptr, false ) );<br />
<br />
    int result = get_device_list( device_ptr ); // It's ok here<br />
    <br />
    free_device_list( device_ptr );<br />
    // And here I got an exception: System.AccessViolationException was unhandled<br />
    // Message="Attempted to read or write protected memory.<br />
    // This is often an indication that other memory is corrupt." <br />
<br />
    Marshal.FreeHGlobal( device_ptr );<br />
}<br />
<br />