static extern void g_list_foreach( IntPtr list, UnmanagedFunc func, IntPtr userData);
static extern void g_ptr_array_foreach( IntPtr array, UnmanagedFunc func, IntPtr userData);
static extern void g_list_foreach( IntPtr list, UnmanagedFunc func, IntPtr userData);
static extern void g_ptr_array_foreach( IntPtr array, UnmanagedFunc func, IntPtr userData);