I didn’t know until just now that you don’t need to include the closing
?> in PHP files that consist entirely of code. The Drupal coding standards explain why you probably want to leave it out:
Note that the final
?>should be omitted from all code files–modules, includes, etc. The closing delimiter is optional, and removing it helps prevent unwanted white space at the end of files which can cause problems elsewhere in the system.
The most common problem it prevents is the “headers already sent” error that crops up when errant line feeds are included at the end of code files.