#!/usr/bin/perl# A simple Perl UDP-Litev4/v6 server which listens on `$PORTNO'use Socket;use Socket6;$PORTNO = 2000;$proto  = getprotobyname("udplite") || 136;socket(SOCKET, PF_INET6, SOCK_DGRAM, $proto)          or die "socket: $!";bind(SOCKET, pack_sockaddr_in6($PORTNO, in6addr_any)) or die "bind: $!";while(1) { defined($src = recv(SOCKET, $msg, 1024, 0)) or die "recv: $!";  ($host, $port) = getnameinfo($src, NI_NUMERICHOST | NI_NUMERICSERV); printf "from %s#%s: $msg\n", $host, $port;}