Why 'Net::Address::IP::Local'->public do not return IP address

ppp has asked for the wisdom of the Perl Monks concerning the following question:

I am perl beginner and under a situation where i have a dongle (USB internet key). When USB is connected and i do :

$address='Net::Address::IP::Local'->public ;
[download]

then it works fine and return an IP address. But i have situation where i have to check disconnect the USB and then check it's IP address using same code but on disconnection it gives an error on writing this command and it is:

Unable to create UDP socket: A socket operation was attempted to an un
+reachable
network. at C:/Perl/site/lib/Net/Address/IP/Local.pm line 166.
[download]

Yes ofcourse it will give error because it will not return any IP address when disconnected. But i wann handle this error. And assign a static IP when it is disconnected like "192.80.13.1". I tried to handle this error this way but out of success:

sub ReturnIpAddress 
{
  if( 'Net::Address::IP::Local'->public =~ m/^(\d\d?\d?)\.(\d\d?\d?)\.
+(\d\d?\d?)\.(\d\d?\d?)$/ )
  {
    return $address= 'Net::Address::IP::Local'->public; #When i try to
+ print this address it print nothing s it crashes because of the erro
+r due to the enteres command i discussed before.
  }
  else
  {
    return $address='192.80.160.16';
  }        
}
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How to handle this error and assign statically $address='192.80.160.16' when USB key is disconnected ?

Comment on Why 'Net::Address::IP::Local'->public do not return IP address Select or Download Code

Replies are listed 'Best First'.
Re: Why 'Net::Address::IP::Local'->public do not return IP address by Laurent_R (Canon) on Jan 16, 2015 at 18:31 UTC
Try to put your block of code in an eval function (and make sure to check the content of the `$@` special variable). Je suis Charlie.	[reply] [d/l]
Re^2: Why 'Net::Address::IP::Local'->public do not return IP address by ppp (Acolyte) on Jan 16, 2015 at 18:56 UTC
you mean something like this : eval { $address='Net::Address::IP::Local'->public =~ m/^(\d\d?\d?)\.(\d\d?\d?)\.(\d\d?\d?)\.(\d\d?\d?)$/ }; warn $@ if $@;	[reply]
Re^3: Why 'Net::Address::IP::Local'->public do not return IP address by Laurent_R (Canon) on Jan 16, 2015 at 22:31 UTC
Well, yes, something like that, or possibly including a bit more of your code in the eval block. You should also probably check the value returned by `eval`, it might be useful. I can't test right now anything really similar to your code, but this "several-liner" should give you an idea of how the `eval` function works: perl -E ' use strict; use warnings; my $output; say "successful statement"; $output = eval {my $c = 4 + 5;}; printout ($output, $@); say "division by 0"; $output = eval {my $c = 4/0;}; printout ($output, $@); say "statement with die"; $output = eval {die "I am dieing\n";}; printout ($output, $@); sub printout { my ($out, $diag) = @_; say $out, "\t", $diag, "\n" if defined $out; say "\t\t$diag" unless defined $out; } ' successful statement 9 division by 0 Illegal division by zero at -e line 12. statement with die I am dieing [download] Je suis Charlie.	[reply] [d/l] [select]
Re^4: Why 'Net::Address::IP::Local'->public do not return IP address by Anonymous Monk on Jan 19, 2015 at 17:26 UTC
Re^5: Why 'Net::Address::IP::Local'->public do not return IP address by Laurent_R (Canon) on Jan 19, 2015 at 18:39 UTC


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