#!/usr/bin/perl

use strict;
use warnings;

use Socket qw(inet_ntoa AF_INET IPPROTO_TCP);

my $AF_INET6       = eval { Socket::AF_INET6() };
my $AF_UNSPEC      = eval { Socket::AF_UNSPEC() };
my $AI_NUMERICHOST = eval { Socket::AI_NUMERICHOST() };
my $NI_NUMERICHOST = eval { Socket::NI_NUMERICHOST() };
# Required for reverse lookup
my $NI_NAMEREQD = eval { Socket::NI_NAMEREQD() };

my %hints = (
    family   => $AF_UNSPEC,
    protocol => IPPROTO_TCP
);
my ( $err, @getaddr ) = Socket::getaddrinfo( $ARGV[0], undef, \%hints );
if ( defined( $getaddr[0] ) ) {
    for my $addr (@getaddr) {
        my ( $err, $address )
          = Socket::getnameinfo( $addr->{addr}, $NI_NUMERICHOST );
        printf "getaddrinfo()/getnameinfo() Address = %s\n",
          ( defined($address) ) ? $address : $err;

        # Reverse Lookup
        my ( $host, $service );
        ( $err, $host, $service )
          = Socket::getnameinfo( $addr->{addr}, $NI_NAMEREQD );
        printf " |_>   getnameinfo()           Name = %s\n",
          ( defined($host) ) ? $host : $err;
    }
} else {
    print "$0: getaddrinfo() failed - error = $err\n";
}