I understand that some products and tools need to have extremely granular permissioning, but what about the underlying filesystem? In a related question, I asked about filesystems than closely compare to NTFS for granularity of permissions support natively.
The classic Unix permissions, read|write|execute for user|group|other, are great. But it seems that they fail when a user is part of more than one group, and a file needs to be accessible to both groups he's in, but no one else (so
rw-rw-r-- is "bad" in this instance). A symlink could be created wherein the other group could read it, or a 'parent' group could be created to hold both of the ones the user is in, and have the file ownership be
user:parent rather than
user:boy, because then the
user:girl group couldn't see it.
What good workarounds to this have you seen/implemented?