Hi, I am writing a script to ping a list of addresses using threads. I have included my script below.

#! /usr/bin/perl
# to check ping from a file of hostnames using threads

#use strict;
use warnings;
use threads;
use threads::shared;
use Net::Ping;
use Time::HiRes;

my $timeout = 5;
my $ping_handle = Net::Ping->new("icmp",$timeout) or die "\n ping unsu
+ccessful. $!";;
$ping_handle->hires();

#Get the host file name and check if valid file
print "\nEnter the host file name:";
chomp (my $host_file = <STDIN>);
open (HOSTFILE, "<", $host_file) or die "\nOpen of $host_file failed. 
+$!";
#assign host_array to list of addresses in file and close
my @host_array = <HOSTFILE>;
close (HOSTFILE);

#Get output file name and check if valid file
print"\nEnter the output file name:";
chomp(my $out_file = <STDIN>);
open (OUTFILE, ">", $out_file) or die "\n Open of $out_file failed.$!"
+;

#debugging
#if($ping_handle->ping("www.google.com")){
#    print "Google works\n";}
#else{
#    print "Ping not working\n";}

my @threads;

foreach $addr(@host_array){
    
    chomp($addr);    
    #print "$addr chomped off\n"; #debugging only
    
    my $thr = threads->new(\&sub_ping,$addr);
    sleep(1);
    push(@threads,$thr);
}

foreach (@threads){
    my $val = $_->join();
    print "Trying to ping $val complete\n"; 
}

sub sub_ping
{
    #check if host is a URL or an IP Address
    my $host= shift; #to get $ARGV[0]

    if (($host =~ m([a-zA-Z]+\.\w+\.\w+)) || ($host =~ m(\d{1,3}\.\d{1
+,3}\.\d{1,3}\.\d{1,3})))
    {
        ($ret, $lat, $ip) = ($ping_handle->ping($host));
        #Check if the valid host responds to pings
        if ($ret)
        {
            printf "$host \($ip\) responds to pings at %.2f msec.\n",$
+lat*1000;
            printf OUTFILE ("$host \($ip\) responds to pings at %.2f m
+sec.\n",$lat*1000);
        }
        else
        {
            printf "$host is NOT responding to pings. Time Taken %.2f 
+msec\n",$lat*1000;
            printf OUTFILE ("$host is NOT responding to pings. Time ta
+ken %.2f msec\n",$lat*1000);
        }    
        $ping_handle->close();
    }
    else #the address is not a URL or an IP Address
    {
        print "$host is NOT a valid address.\n";
        print OUTFILE ("$host is NOT a valid address.\n");
    }
    return $host;
}
[download]

The above script works fine for all hosts which are responding. Personally if i give a host in the same network, the latency from it is a teeny tiny bit higher than what i get when i use Ping in the command line.

However, if i encounter any hosts that are not responding, then i do have a problem. Every host after that becomes NOT RESPONDING. Since its via threads, the results vary each time - sometimes its only 2 hosts not responding ( apart from the existing not responding one) sometimes its 3.

Can someone pls help me with this ?