App for files

[coopf]

I'm trying to make an app that will move files from it's own directory on a ipod or iphone to other locations and change some permissions (Like mv and chmod and .sh in terminal), or even better to be able to run a shell file from an app to do all of this. My current problem is that I don't know how to name a file that I don't know (/var/mobile/Applications/<some code>/My App/Files that need to be moved) or can I deside what the code is?

Thanks in advace