#!/usr/bin/perl
use warnings;
use Net::Ping;
use Socket;

print "Enter the subnet you wish to scan just the first 3 octet's\n";
$ipnumber =<STDIN>;
chomp $ipnumber;
@iparray = map $ipnumber. ".$_",1..254 ;
print @iparray;
#open (ERRORLOG, ">errorlog");
open (OFFLINE,">offline");
#my @iparray = qw( www.slashdot.org www.deja.com  www.perlmonks.org );


my $proto = 'icmp';
my $def_timeout = '0';
my $bytes = '64';

my $p = Net::Ping->new($proto,  $def_timeout , $bytes);

foreach my $host (@iparray) {
  $| = 1;
     print "$host online \n" if $p->ping($host);
     print "$host offline \n" unless $p->ping($host,1);
     print "$host \n" unless $p->ping($host,1);
}
$p->close();
close OFFLINE;
#close ERRORLOG;


open (IPLIST, "offline");
#open (OFFLINEHOST, ">offlinehost");
@list=<IPLIST>;
$list = @list;
#print "@list\n";
chomp @list;
my $i;
my $peer_host;
format STDOUT_TOP =
IP#              Machine name
---------------- ------------------------------------
.
format STDOUT =
@<<<<<<<<<<<<<<< ^<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
$i,         $peer_host
.
foreach $i (@list) {
$peer_host = gethostbyaddr(inet_aton($i), AF_INET);
#$peer_host = gethostbyaddr(inet_aton($i), AF_INET);
#print OFFLINEHOST "$peer_host and ipaddress $i\n";
#print OFFLINEHOST "$peer_host and ipaddress $i\n";
write
}
close OFFLINE;
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For some reason it seems the format command splits the list why is that