include files

Hi, Is it possible under PHP4 to get the name of the file that a function was called from? To clarify, here's an example of what I'd like to do: --- main.php --- <?php include('include.php'); function foo(){ $include_file=file_that_called_foo(); printf($include_file); } ?> --- include.php --- <?php foo(); ?> Does anyone know of a way to do this? I've tried several different things, including to constant '__FILE__ ', but they all return the current file, I am needing the included filename.