Gnu/coreutils/hostname-invocation

From Get docs

21.5 hostname: Print or set system name

With no arguments, hostname prints the name of the current host system. With one argument, it sets the current host name to the specified string. You must have appropriate privileges to set the host name. Synopsis:

hostname [name]

The only options are --help and --version. See Common options.

hostname is not installed by default, and other packages also supply a hostname command, so portable scripts should not rely on its existence or on the exact behavior documented above.

An exit status of zero indicates success, and a nonzero value indicates failure.