Here is a code fragment from some C++ code:

Header File 1 declaration (this is supplied by a third party vendor:

class User;
DLL_API User* pickUser( Global* g,  User** users, int numUsers );

The documentation states that "The 'users' are a list of User pointers"

I have a C++ class that wraps this api as follows:

DLL_API long MyPickUser(long g,  long** users , int numUsers)
{
       
    return( (long) ::pickUser( (Global* ) g,  (User** ) users, numUsers));
}

In my CSharp class I have set up the following:

[DllImport("MyWrapper.dll", CharSet=CharSet.Auto)]
        private static extern int MyPickUser(int g, ref int[] users, int numUsers);

internal int PickUser(ref int[] users,int numUsers)
{
   int ret;
   try
   {
   ret = MyPickUser(miGlobal, ref users,numUsers);
   return ret;
   }
   catch (Exception ex)
   {
    HandleError(ex,"PickUser");
    return 0;
   }
}

public int PickUser()
{
  int[] iUsers;

  iUsers = new int[1];
  //The UserId is a pointer to a User obtained from a previous call to the
C++ module.
  iUsers[0] = Users.Item(0).UserId;

  int usr = PickUser(ref iUsers,1);
      return usr;
}

From what I can tell the third party dll is not getting the array of users
and is returning a 0 (there indicator an error occurred).  How do you do this
correctly?