Is use this way, but you need to declare a host for the machine, or you get 127.0.0.1: 
  use Socket;
  use Sys::Hostname;
  my $host = hostname();
  my $address = inet_ntoa(scalar gethostbyname($host || 'localhost'));
  
  print "$host > $address\n" ;

[download]
For me this works on Linux and Win32, and I use a cable modem too.

Graciliano M. P.
"The creativity is the expression of the liberty".

In reply to Re: Detecting when my ISP changes my IP by gmpassos
in thread Detecting when my ISP changes my IP by meonkeys

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