Thomas... but it seems that the program scans the whole system... root included... :/
So i think that there are really too much directories in which put the file..
A reverse procedure could be the best solution.. :/ (A file that indicate the program if the directory has to be seen, not to be ignored..)
Or maybe, for not leaving files around the directories of the whole n900, could be great adding the "watched" directories in a simple text file, with a patch to a directory for every string.
No way to do something?

If this was bash i could help you :/