I've two functions. currentHeadline looks in $_GET for a variable
called 'image' and prints what it finds. showThumbnail takes an image
for a parameter and resizes it before sending it to the screen. But
when I do this:

<?php showThumbnail(currentImage(), 20, 20); ?>

showThumbnail is telling me that it is not being given a file name, and
currentImage is printing the file name to the screen. How is that
possible? What is the right way to do this?