Been a while since you've seen DEC, the acronym for the late, Digital Equipment Corp., in a headline, and this might be the last time.
AdvFS offers solid security and back-up features, along with fine-grain control of file systems and free space, according to the SourceForge page. The documentation for AdvFS is living on the H-P site.
For you younger readers DEC once defined the mini-computer space, and sold out to Compaq in 1998, which then sold-out to H-P four years later.
However it may be best known for this 1977 quote from co-founder Ken Olsen. "There is no reason for any person to have a computer in his home."
At that time DEC ruled the computing roost, and Olsen was sneering at a 22 year old kid's start-up, called Micro-Soft. The kid retires this week, aged 53, and probably made a million dollars while I typed this sentence.
Let that be a warning to the kid's successors. Feel free to add your favorite DEC stories to the comment thread. Be careful, though. Wikipedia says that Olsen, unlike George Carlin, is still with us.