2Re: My 2004 Perlish Wish

If you happen to be using an operating system that implements fork, then you don't need threads to achieve parallelism (in fact, some programmers spells threads F-O-R-K). I would look into LWP::Parallel (well, the ParallelUserAgent distro, to be exact). In the meantime, here is an extremely trivial, bare bones script with issues that uses HTML::LinkExtractor (think HTML::LinkExtor::Simple) and fork to check links in parallel (Quiz: what limitation is allowing us to achieve parallelism even though only one processor may be all that's available to us? ;))

# be careful with this ... a fork is executed for every link found
use LWP::Simple;
use HTML::LinkExtractor;

my $link = HTML::LinkExtractor->new;

$link->parse(\*DATA);

my @href = map $_->{href}, grep { $_->{tag} eq 'a' } @{$link->links};

for (@href) {
   next if fork;
   my $valid = head($_) ? 'good' : 'bad';
   warn "$_ is $valid\n";
   exit;
}

__DATA__
<ul>
<li><a href="http://www.perlmonks.org">Perlmonks</a></li>
<li><a href="http://www.yahoo.com">Yahoo</a></li>
<li><a href="http://bad.link.number.one">Bad #1</a></li>
<li><a href="file://not.there"></a>Bad #2</li>
</ul>
[download]

Mr. Peabody Explains Fork

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

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