I'm trying to determine if the link is up and running before I try and retrieve something. The idea is that the script spends most of its time asleep and wakes up every x minutes. If it can see a connection it goes and gets something (actually some weather data from a local airport) otherwise it sleeps again.

have you tried somthing like

$minuits_to_wait = '5';
$last = my $last2 = 0;

while (1) {
    if ((time - $last) > 60 * $minuits_to_wait ) {
        $ret = sometypeof-ping-routine();
        if ($ret eq '1') {
            get_somthing();
        } elsif ($ret eq '0') {
            print "Not connected\n";
        }
    }
    
    sleep(60 * $minuits_to_wait);
}
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If you have auto-dial set to off, you can simply ping the gateway machine, using Net::Ping. If the ping comes back, you are connected. The Cable Modem Check program by Ozymandias does more or less what you want then - but it uses the ping command which is available under Win32 as well but has slightly different output. The program also tries to reconnect the cable modem, which you don't want to do either. But it should be easy to modify the script to suit your needs.

The problem starts if auto-dial is enabled. Then that ping will connect you, which is what you wanted to avoid in the first place. I haven't found a good way yet to detect a modem connection. You could try to open COM2 or whatever port your modem is connected to, and if an error occurs, you "guess" that you are connected, you can then try the above ping.

Update: KM posted the method to go by if you want to open the serial port(s). And jcwren posted the ipconfig trick, which will show you a NDISWAN adapter for the remote connection.

Cheers,
KM

So, it could be as simple as:

if ($whatever_key) {   print "I'm online!\n";  }
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Win32::RASE makes checking the internet connection status possible, if one digs a bit deeper. I've thought about doing a "real" program for this, but now I see that Perl already has the necessary bindings for connection checking :).

To use Win32::RASE to check the internet connection, I'd do something like the (untested) following :

  use strict;
  use Win32::RASE;

  my (%connections, $entry, $hrasconn);
  
  %connections = RasEnumConnections();
  foreach $entry (keys %connections) {
    my $status;
    $hrasconn = $connections{$entry};
    $status = RasGetConnectStatus( $hrasconn );
    if ($status == RASCS_DeviceConnected) {
      print "Computer is online via $entry\n";
    };
  };
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I image there is some funky registry entry or something you can check, maybe look for a routing table entry out the PPP interface. But I almost never touch Windows, so I can't vouch for a more internal method being available.

I use dial on demand so I don't want to initiate a connection if there isn't one already. I was trying to avoid (for the obvious reasons) any complicated registry manipulation.