Autocomplete SSH, SCP, ping, ..., based on known hosts.

ssh-autocomplete

#!/usr/bin/env bash

get_ssh_known_hosts() {
    known_hosts=$(cat ~/.ssh/known_hosts | cut -d' ' -f1)
    starts_with=$2
    COMPREPLY=( $(compgen -W "$known_hosts" -- "$starts_with") )
    return 0
}

complete -F get_ssh_known_hosts ssh scp ping nslookup my-custom-command

For reference: https://www.gnu.org/software/bash/manual/html_node/A-Programmable-Completion-Example.html