[CentOS] Why are dots in username & groupname no longer allowed?

Thu Jan 5 18:30:33 UTC 2006
Robin Mordasiewicz <robin at bullseye.tv>

On Thu, 5 Jan 2006, Benjamin Smith wrote:

> Try this one:
>
> chown -R c.smith.users /home/c.smith
>
> See the problem?
>
what about
chown -R c.smith:users /home/c.smith