Well, it should be the same in batch or bash, you will just need to change the variable references and figure out your own for loop.
As a general rule of thumb, the people here are Linux users and don't necessarily know how to write stuff using the cmd.exe paradigm.
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Personally, I would recommend doing this as a KUAL extension. That way it can be reused with a click of a button.
In fact, NiLuJe, how about you add some sort of staging folder to the hack that people can use to process their images (via a KUAL trigger?) to add to their screensaver pool.
