sub ReadURLS {
  my ($queue,$filename) = @_;

  open my $urlFile,'<',$filename or die "ReadURLS: bad file!: $!" #Use three arg open for security reasons, die on errors so we don't spew nonsense or crash worse later.
  $queue->enqueue(<$urlFile>,undef); #Place each line into the queue, followed by undef to signal the end of data.
  return 1; # Success! Return true. Or, if you're a unixy person, return 0 or maybe even 0 but true.
}

# Inqueue should be the queue object passed to ReadURLS
# Outqueue should be the queue object passed to ParseContent
sub DownloadContent {
  my ($outqueue,$inqueue) = @_;

  # Each thread needs their own UA
  my $ua = LWP::UserAgent->new;
  $ua->agent("Mozilla/4.0 (compatible; MSIE 5.0; Windows 98; DigExt)");
  $ua->timeout(15);

  while (my $url = $inqueue->dequeue){ #wait for data and abort when undef comes down the pipe (that means theres no more)
    #this part should look familiar
    print "Downloading: $url\n";
    my $req = HTTP::Request->new(GET => $url);
    my $response = $ua->request($req);
    $outqueue->enqueue($response->content()); #this changes, send the output to the next task handler.
  }
  $outqueue->enqueue(undef);
  return 1; # See above return
}

# inqueue should be the outqueue from the downloader sub
# outqueue should be passed to the output sub.
# regex is of course, your regex. This allows for re-use of the code. You could also consider taking some parsing rules and using and HTML parser of some type...
sub ParseContent {
  my ($outqueue,$inqueue,$regex) = @_;
  
  while (my $content = $inqueue->dequeue) {
    $outqueue->enqueue(join '',$content =~ m/$regex/m,"\n");
  }
  $outqueue->enqueue(undef);
  return 1;
}

# queue should be the outqueue passed to ParseContent
sub WriteOut {
  my ($queue,$filename) = @_;

  open my $outFH,'>>',$filename or die "WriteOut: open failed: $!";
  while (my $data = $queue->dequeue) {
    print $outFH $data;
  }
  close $outFH;
  return 1;
}