You may ask "Why another version of the hostname command?". The answer is
simple. A lot of people misuse the domainname command to get the DNS domain
name. Since the domainname command should ONLY be used to set/show the NIS
domain name (formerly known as Yellow Pages) there was no easy way to get
the FQDN (Fully Qualified Domain Name) or the DNS domainname from within a
shell script.

This hostname command offers you some additional features:

- show the FQDN (long host name)
- show the short host name
- show the DNS domain name
- read the host name from file

For further informations simply type "hostname --help" or read the manual
page.

If the program is called as dnsdomainname it will simply show the DNS domain
name.

If you ONLY use the loopback mode you can only use the normal features
(set/show the host name) since you probably don't have a FQDN (Fully Qualified
Domain Name) in the /etc/hosts file. You can change this by either using
the dummy device or by changing the localhost line in /etc/hosts to
something like this (it will use localhost as an alias name):

127.0.0.1	erdos.maths.groucho.edu		localhost erdos