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IO::Socket::PortState - Perl extension for checking the open or closed status of a port.


   use strict;
   use warnings;
   use IO::Socket::PortState qw(check_ports);

   my %porthash = ( ... );


   for my $proto (keys %porthash) {
      for(keys %{ $porthash{$proto} }) {
         print "$proto $_ is not open ($porthash{$proto}->{$_}->{name}) if !$porthash{$proto}->{$_}->{open};


You can use it to check if a port is open or closed for a given host and protocol.


None by default. But you can export check_ports();


This function tests your \%porthash and sets a protocol/port's open and note keys (see \%porthash below for details).

By default it determines if "open" is 1 or 0 if the IO::Socket::INET object is defined or not. For protocols not supported by IO::Socket::INET or for custom tests (IE open just to specific hosts, closed because activley blocked, service is down, etc) use \&handler (see \&handler below)


Called in void contect it modifies the hashref given. Otherwise it returns a new hash ref which is usefull for looping through the same \%porthash for multiple hosts:

  my %porthash = ( ... );
  for(@hosts) {
     my $host_hr = check_ports($_,$timeout,\%porthash);
     print "Report for $_\n";
     # do something with $host_hr

vs void context:

  my %porthash = ( ... );
  # now %porthash has been directly changed


This hash is a bit complex by necessity. (but its not so bad ;p)

The keys are the protocol (tcp, udp, ...) as can be used by IO::Socket::INET->new()'s "Proto" option (or whatever is valid for your custom \&handler

The values are a hashref. In this hashref the keys are the numeric ports and the valuse are a hashref.

This hashref has only one key "name" whose value can be an arbitrary label for your use and once run it sets "open" to 1 or 0 and "note" to "builtin()" so you knwo how "open" was figured.

   my %check = (
      tcp => {
         80 => {
            name => 'Apache', 
         443 => {
            name => 'SSL Apache',
      udp => {
         53 => {
            name => 'DNS'
         465 => {
            name => 'smtp tls/ssl'


Here is an example handler function you can use as a road map:

    sub handler {
       my($ent_hr,$host,$port,$proto,$timeout) = @_;

       # use $host, $port, $protocol, and $timeout to determine what you want however you like here

       # at a minimum do these two:
       $ent_hr->{open} = ???; # do what you like to set its open status to 1 or 0
       $ent_hr->{note} = 'my handler()'; 

       # set any other info you wanted here also...
       if(!$ent_hr->{open}) {
          $ent_hr->{closed_reason} = ???; # do what you like to set details about why its not open (blocked, not running, etc)

HOW TO EXPAND ON IO::Socket::PortState

This module's life came around as a result of wanting to monitor specific ports on several servers, specifically servers running cPanel ( To make it easier to do that and provide a model to make it easier for anyone to create a module that is "server specific" I've created IO::Socket::PortState::cPanel

If you want to do the same thing please use it as a guide, all you would need to do is change the hashrefs and package specific info and voila its all set :)

If you do use IO::Socket::PortState::cPanel as a model (and I hope you do so that using any IO::Socket::PortState::* module will have a specific consistent use) please reference it in the POD of your module as outlined in the POD of IO::Socket::PortState::cPanel.


Daniel Muey,


Copyright 2005 by Daniel Muey

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.