set group id on directories

Marc Samama (marc@tky.icdc.fr)
Thu, 2 Mar 95 20:00:36 JST

I'd like to know if a sgid bit on a directory represents a security risk,
given the fact that the directory is not world or group writable.

On my system, whereas the manual states that this bit is ignored on 
directories, a file created on such a directory is owned by the same 
group that posses the dir, and any child directory has the same sgid bit,
by default.

It this feature commonly used anyway?

Marc.