cut -f 1 -d ' ' ~/.ssh/known_hosts | perl -p -e 's#,#\n#' | sort -u | perl -e 'chomp(@x = <>); print map {"$x[$_]\n"} grep {$x[$_ + 1] !~ /^$x[$_]\..+$/m} (0 .. $#x);' > ~/.known_ssh_hostnames
alias list_all_hostnames cat ~/.known_ssh_hostnames
complete scp 'p/*/`scp_completions`/'