use strict;
use warnings;
use Net::Ping;

my $host = '127.0.0.1';

# Protokoll TCP
my $p = Net::Ping->new('tcp');
unless (defined $p) { die "can't create Net::Ping object $!";}

if ($p->ping($host)) { print "$host reachable via TCP\n" ; }
else                 { print "$host unreachable via TCP\n"; }
$p->close;

# avoid network flooding
sleep(1);

# Protokoll UDP
$p = Net::Ping->new(); # UDP ist Voreinstellung
unless (defined $p) { die "can't create Net::Ping object $!";}

# Exceptions auffangen
eval
  {
  if ($p->ping($host)) { print "$host reachable via UDP\n"; }
  else { print "$host unreachable via UDP\n"; }
  };

if ($@) { print "$@: UDP failed\n"; }
undef $p;

# avoid network flooding
sleep(1);

if ($> == 0)
  {
  # Falls das Programm als 'root' (UID 0) läuft
  # Protokoll 'icmp' verwenden
  $p = Net::Ping->new('icmp');

  unless (defined $p) { die "can't create Net::Ping object $!";}

  if ($p->ping($host)) { print "$host reachable via ICMP\n"; }
  else { print "$host unreachable via ICMP\n"; }
  undef $p;
  }