Thanks, I am having a look to deepcopy, it may prove useful and efficient for me to play similar tricks.

As for why I need long pathnames, I guess it is not a germane issue here, but you are essentially right: I put in pathnames information which could (and perhaps should) be stored elsewhere. In a nutshell, (1) standard meta-data tags are all but standard content-wise and every second program thinks to be in the right to mess them up and be more clever than the previous tagger, and (2) a home-cooked database storage is invisible to all but my programs whereas directory structures are visible to all, in every OS, in every system, and I can control them quite freely. Not elegant, not the ideal solution, questionable under many aspects, but works quite fine for me--were it not for some limitations of some OSs. Luckily there are other OSs readily available around. But it is an exquisitely personal choice dictated by practical reasons--in principle you are probably perfectly right.

Thanks,