#!/usr/bin/perl -w

# Here, we're calling two modules or additions to Perl. The first one we
# installed on the server specifically for this occasion, but 'use
# strict' is a helpful little addition if you want to write good code.
# It catches a lot of the human idiocy that plagues horrible programs.
use XML::RSS;
use strict;

# create some variables near the top of the script so we don't
# have to search through the script later to change them.
my $headlines_file = "/path/to/headlines.html";
my $rss_output = "/path/to/headlines.rss";

# we create a new rss object.
my $rss = new XML::RSS (version => '0.9');

# these are just little descriptive elements of the RSS channel we're 
# about to make. we add them to the $rss object we made above.
$rss->channel(title => "Your Site Name",
              link => "http://www.yoursitename.com/",
              description => "Headlines from Your Site Name!",
             );

# we open the file with our headlines in it.
open(FILE, "<$headlines_file") or die "Couldn't open $headlines_file: $!";

# a traditional while loop. for each line of our $headlines_file
# we start looking for markers within the code that tell us a
# headline is coming. in this example, we're assuming that headlines
# follow html like <h2><a href="link">headline</a></h2>.
while (<FILE>) {

   # look in the current line to see if our headline is in there.
   if ($_ =~ /<h2><a href=\".*\">.*<\/a><\/h2>/) {

      # if it is, then we grab the link and headline.
      my ($link, $headline) = /<h2><a href=\"(.*)\">(.*)<\/a><\/h2>/i;

      # if both $link and $headline were created, then we
      # add them to the $rss object using the add_item feature
      # of XML::RSS.
      if ($link and $headline) {
         $rss->add_item(title=>$headline, link=>$link );
      }

      # move on to our next line.
      next;
   }
}

# if we're this far, we've finished our file.
close(FILE);

# finally, save the rss file.
$rss->save($rss_output);

# and quit.
exit;