#!/usr/bin/env perl -l

use strict;
use warnings;

use LWP::Simple;
use Parallel::ForkManager;

my @urls = qw{
    http://us.a1.yimg.com/us.yimg.com/i/ww/m5v9.gif
    http://hooboy.no-such-host.int/
    http://www.yahoo.com
    http://www.ora.com/ask_tim/graphics/asktim_header_main.gif
    http://www.guardian.co.uk/
    http://www.pixunlimited.co.uk/siteheaders/Guardian.gif
};

my $max_processes = $ARGV[0] || 8;

my $pm = Parallel::ForkManager::->new($max_processes);

print 'Start link checking.';

for my $url (@urls) {
    $pm->start and next;

    my ($type, undef, $mod) = head($url);

    if (defined $type) {
        print "PASS: $url";
        print '  MOD: ', $mod || 0;
    }
    else {
        print "FAIL: $url";
    }

    $pm->finish;
}

$pm->wait_all_children;

print 'Link checking completed.';

##</code><code>##

$ pm_1199760_parallel_forkmgr_link_checker.pl
Start link checking.
FAIL: http://hooboy.no-such-host.int/
PASS: http://us.a1.yimg.com/us.yimg.com/i/ww/m5v9.gif
  MOD: 1354074654
PASS: http://www.guardian.co.uk/
  MOD: 0
FAIL: http://www.ora.com/ask_tim/graphics/asktim_header_main.gif
PASS: http://www.yahoo.com
  MOD: 0
FAIL: http://www.pixunlimited.co.uk/siteheaders/Guardian.gif
Link checking completed.

##</code><code>##

$ pm_1199760_parallel_forkmgr_link_checker.pl 1
Start link checking.
PASS: http://us.a1.yimg.com/us.yimg.com/i/ww/m5v9.gif
  MOD: 1354074654
FAIL: http://hooboy.no-such-host.int/
PASS: http://www.yahoo.com
  MOD: 0
FAIL: http://www.ora.com/ask_tim/graphics/asktim_header_main.gif
FAIL: http://www.guardian.co.uk/
FAIL: http://www.pixunlimited.co.uk/siteheaders/Guardian.gif
Link checking completed.