HOSTNAME(1) General Commands Manual HOSTNAME(1)

hostname — set or print name of current host system

hostname [-f] [-s | -d] [name-of-host]

The hostname utility prints the name of the current host. The super-user can set the hostname by supplying an argument. To keep the hostname between reboots, run ‘scutil --set HostName name-of-host’.

Options:

Include domain information in the printed name. This is the default behavior.
Trim off any domain information from the printed name.
Only print domain information.

Set the host name of the machine and check the result:

$ hostname beastie.localdomain.org
$ hostname
beastie.localdomain.org

Do not show domain information:

$ hostname -s
beastie

Show only domain information:

$ hostname -d
localdomain.org

gethostname(3), scutil(8)

The hostname command appeared in 4.2BSD.

October 5, 2020 macOS 15.0