Using specific PHP functions with Includes

How can I use the 'htmlspecialchars' and 'nl2br' functions in PHP with an
include?

I want to include a text file on a page, but I want it displayed just how it
would be in notepad, with all of its line breaks and HTML tags shown as plain
text.


I have tried these so far, but they do not work:

readfile(nl2br(htmlspecialchars($filename)))

nl2br(htmlspecialchars(readfile($filename)))