A Kettle job has several entries that allow you to get a set of filenames to do something with. Jobs themselves don't really make much use of this list, so this page is devoted to seeing what you can do with these lists in a transformation.

The most important component is Job/Get files from result. This component will load the file list from the job that called this transformation.

Now that you have loaded this list of files, what can you do with it? Well, it basically becomes data, and you can do transformations on it.

You could use Utility/Process files.
You could use Utility/Mail to mail the files (but you can do that in a job as well).
You could use Utility/Execute process to run some external command.

Not a whole lot of choices of actually doing something with the files themselves, just the filenames as data.