That's simple enough. And can be useful if you hit one of the "find my IP" sites to also get your DHCP-assigned IP as a bonus. Hitting google is very dangerous.

(re-ordered for thematic reasons) Thanks all for responses.

This simple advice came just in time for me to ask the comcast guy the address. It isn't the old 192.0.0.1 it used to be, and the page seems to have more functionality than I recall.

I'd like to unpack this a bit. First, I do have a working script:

$ ./1.lwp.pl 
execution here
execution there
$ cat 1.lwp.pl 
#!/usr/bin/perl
use 5.016;
use warnings;
use LWP::Online 'online';

say "execution here";
# "Is the internet working?"
die "NO INTARWWEB!!!" unless online();
say "execution there";
__END__
$
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I attempted to dig through a few parts of this listing for Online.pm. I have any number of questions after having contended with the source for several days now. Regarding this snippet:

# Set up configuration data
use vars qw{%SUPPORTED @RELIABLE_HTTP};
BEGIN {
        # What transports do we support
        %SUPPORTED = map { $_ => 1 } qw{ http };
 
        # (Relatively) reliable websites
        @RELIABLE_HTTP = (
                # These are some initial trivial checks.
                # The regex are case-sensitive to at least
                # deal with the "couldn't get site.com case".
                'http://www.msftncsi.com/ncsi.txt' => sub { $_ eq 'Mic
+rosoft NCSI' },
                'http://google.com/'               => sub { /About Goo
+gle/         },
                'http://yahoo.com/'                => sub { /Yahoo!/  
+             },
                'http://amazon.com/'               => sub { /Amazon/ a
+nd /Cart/    },
                'http://cnn.com/'                  => sub { /CNN/     
+             },
        );
}
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What is happening with the subs here?

You get about hip deep in it and need to look at source for LWP::Simple. Is this a core module?

In this snippet from LWP::Online, how does it import a lexical variable?

use LWP::Simple 5.805 qw{ get $ua };
 
use vars qw{$VERSION @ISA @EXPORT_OK};
BEGIN {
        $VERSION = '1.08';
 
        # We are an Exporter
        require Exporter;
        @ISA       = qw{ Exporter };
        @EXPORT_OK = qw{ online offline };
 
        # Set the useragent timeout
        $ua->timeout(30);
}
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This is get in LWP::Simple

sub get ($)
{
    my $response = $ua->get(shift);
    return $response->decoded_content if $response->is_success;
    return undef;
}
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How would one add his own site to @RELIABLE_HTTP?

Thanks for your comments

WRT your last question, @RELIABLE_HTTP is a package variable so you should be able to push (or otherwise manipulate it) after you've pulled in the module.

use LWP::Online;
push @LWP::Online::RELIABLE_HTTP, q{http://groot.example.com} => sub {
+ /I AM GROOT/ };

## Call http_online however . . .
[download]

The cake is a lie.
The cake is a lie.
The cake is a lie.

What is happening with the subs here?

They are used by the code in the sub http_online as $check, where first $_ is set to the content fetched from the URL, and then the sub is called, and its return value used as a boolean. Although the subs you see here could be done by precompiled regexes (qr//), a sub allows for much more flexibility, a simple example being the sub { /Amazon/ and /Cart/ } case.

LWP::Simple. Is this a core module?

No, as you can find out with the corelist command:

$ corelist LWP::Simple
...
LWP::Simple was not in CORE (or so I think)
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However, the module's distribution, libwww-perl, is quite often used by scripts, so that e.g. Strawberry Perl includes it, and it's fairly common to find it already installed alongside Perl on many *NIX systems.

In this snippet from LWP::Online, how does it import a lexical variable?

Just to nitpick, it's not a lexical variable, it's a package variable. They can be exported/imported just like subs, e.g. Exporter supports this.

You can change @RELIABLE_HTTP in the source code. Best regards, Karl