How long should I keep a file on my system?

[Newbie164]

My hard drive is pretty full and I want to delete some of my downloaded torrent files. In order to be a "good" participant in the p2p community what would be a recommended time I should keep a file available before deleting it?

My second, perhaps silly question, how can I differentiate pirated material from freely available material?

Thanks!

[paintball9]

Ideally it would be until you upload as much as you downloaded on that particular torrent. Most people will say a few days if you don't reach that size limit.

And for your second question, either common sense or a simple google search should tell you pretty quickly what's a paid for product or released under gpl/public domain.

[Newbie164]

Thanks much.