What is a recommended setup for
I know about user / group / other, about sgid flag and I know what User Private Groups are. I have read the comment about
adduser no longer setting sgid on
/home/<user> "because of bad side-effects". So apparently the original User Private Group setup is no longer "the way to go".
What I did not find was any hint as to what the recommended "way to go" is with regards to user permissions and groups in
Use case: Family computer, four users, two parents, two kids, and I want to share certain files / directories and prohibit access of the kids to others. I know half a dozen ways to do this, but what is recommended (so I avoid roadblocks I haven't thought about yet)?