> You are not including the source code of l.php but the result of it being
> run on the server, which is just the string "define function...defined",
> which in turn is interpreted as HTML and displayed by t.php. You must
> either include the file locally (e.g. require "/home/derek/l.php";) or
> make the server not interpret the file (e.g. by giving it another
> extension like ".inc" or ".txt").

Ah, right. Thanks. But just to clarify, if I rename it to something other
than .php, and someone learns the pathname to the file, they can ask my
webserver for the file directly and they'll get to see my source code -
right?