Andrew Brown said:

>in sysv, files and directories are created according the primary group
>of the creator.  in bsd, they are created according to the group of
>the directory in which they are created.  sysv can usually emulate bsd
>group behavior by means to setting the sgid bit on a directory.

>in both systems, users can be in multiple groups and once and can
>chgrp files and directories (that they own) between them at their
>leisure.

Assuming a file that is 750 or 640. If you are in the correct group on
BSD, but not the owner, you can execute or read the file. If you are
on SYSV, you must newgrp to reset your effective GID in order to access
the file.

-- 
Rick Kelly  rmk@rmkhome.com  www.rmkhome.com