This falls short of meeting the OP's clear and simple specification in two ways:

• It doesn't look in subdirectories.
• It doesn't bother to check whether $file is actually a file (not everything that shows up in a directory needs to be a file.), so even in the directory that it does process, it's not providing accurate results.

Remember, the OP wanted to find all files in a directory, including those found in subdirectories.