Here are the examples from the hostid man pages:
Examples
1. To set the identifier of the local host to the local Internet address with
the hostid command, enter the command in the following format:
hostid 192.9.200.3
0xc009c803
The hostid command converts the Internet address 192.9.200.3 into the
hexadecimal representation 0xc009c803, and then sets the local host (your
workstation connected to a network) to this address.
2. To display the identifier of the local host, enter:
hostid
0xc009c803
The hostid command displays the identifier of the host as a hexadecimal
number.