I got the module and this is how they do it: 
my $ip_rgx = "\\d+\\.\\d+\\.\\d+\\.\\d+";
sub ipv4_chkip($) {
  my ($ip) = $_[0] =~ /($ip_rgx)/o;
  
  return undef unless $ip;
    
  # Check that bytes are in range
  for (split /\./, $ip ) {
    return undef if $_ < 0 or $_ > 255;
  }
  return $ip;
}

[download]
Perfect, I'm not going to use the module for my application though because I wanted it to run off standard packaged modules so some totally inept computer users could make use of the script without my assitance. The code however may be making an appearance -- Thanks.

In reply to Re: IPv4 regex (Net::IPv4Addr) by ryan
in thread IPv4 regex by ryan

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