The basic premise for XML::Parser is that you define subroutines which get called when a start tag is found, an end tag is found or character data (i.e. between two tags) is found.

From your question, it looks like you need some help with the subroutines.

The three variables $p, $elt, %atts in the tutorial are defined as follows:

sub hdl_start{
      my ($p, $elt, %atts) = @_;
      return unless $elt eq 'message';  # We're only interrested in wh
+at's said
      $atts{'_str'} = '';
      $message = \%atts; 
  }
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This snippet defines a subroutine called hdl_start. It gets called whenever the parser discovers a start tag (like <chatter>. The parser passes three parameters to the subroutine in the array @_. The first line in the subroutine (my ... then extracts those parameters from the array into the $p, $elt, %atts variables. The documentation for XML::Parser tells us that the parameters are:

• Expat ($p) is a reference to the underlying Expat XML parser.
• Element ($elt) is the name of the element found - e.g. chatter
• Attr, Val (%atts) are attribute / value pairs found as part of the start tag

So, to use a bit of the XML from the tutorial: <INFO site="http://perlmonks.org" sitename="Perl Monks">

• $elt would contain 'INFO'
• %atts would contain
  

  site => 'http://perlmonks.org'
  sitename => 'Perl Monks'
  [download]

I think perhaps you may want to read some of the other Tutorials and may want to invest in the "Learning Perl" (llama) book. Tackling Perl and XML::Parser as your first project may be a little ambitious!