The sysop here bodged the /etc/hosts file so that 'hostname' worked sort of correctly, now I've removed the bodge 'hostname' doesn't work right any more.
At home (Slackware) I get:-
home$ hostname -s home home$ hostname home home$ hostname -f home home$ domainname (none)
Here on this Fedora box I get:-
$ hostname chrisg.localdomain $ hostname -s hostname: Unknown host $ hostname chrisg.localdomain $ hostname -f hostname: Unknown host $ domainname GEMS