Setting hostname

[cfk]

I have a number of systems that move around. They dont always stay on a 
particular domain and sometimes they are on no domain at all.

I'm having a little problem understanding the setting of hostname in 
FedoraCore2. It seems to be a little different then RH8 or RH9. 

I have tried setting my needed hostname, say "testSystem3" into /etc/hosts at 
the end of the 127.0.0.1 line. I have also tried creating a /etc/HOSTNAME 
file. Neither seems to work reliably.

My current need is to identify several different xterms that are all ssh'ed to 
different computers. Additionally, I have a Tcl/Tk script that depends on the 
utility hostname returning something useful and settable.

Charles