Recently I wrote a piece of code to make human readable digest versions of XML logfiles that are generated from the Kana customer service email server.

Once I was done I started testing my code & voila I was bitten! By parsing XML by hand I forgot that parameters could come in any order & so my code broke when I passed in a logfile generated from Kana's email-a-log function, in which the parameters for a certain tag are given in a different order.

So... I set out to learn how to use XML::Parser & stop trying to reinvent the wheel... DUH!

It works! And (not so)incredibly it's almost 100% faster than the routine I wrote.

Now I have a different problem.

I find that when I call $p->parsefile() I'm getting the first line of the XML files printed to the screen. (Assumably to STDERR) For example:

<?xml:stylesheet type="text/xsl" href="log.xsl"?>

Now I assume that this is going to STDERR because I found that when I put in a die, parsefile would fail. However, when I comment it out, it continues to function properly...Like so:

    my $p=new XML::Parser(Style=>'Stream') 
        or die ("Couldn't make new Parser\n$GOODBYE\n");
    $p->parsefile($logfile, ErrorContext => 0) ;
        #or die ("Couldn't invoke parsefile in XML::Parser...\n$GOODBY
+E\n");
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Why is it doing this & how do I handle it more gracefully?

I went so far as to modify StartTag to try to handle it, but that didn't do anything either...

sub StartTag {
  my ($expat,$eltype)=@_;

  if ($eltype eq "log") {
      $version    = $_{version};
      $datestamp    = $_{date};
  } elsif ($eltype eq "node") {
  } elsif ($eltype eq "component") {
  } elsif ($eltype eq "?xml:stylesheet") {
  } elsif ($eltype eq "m") {
    $p[i] = $_{p};
    $component_type[$i] = $_{c};
    $datetime[$i] = $_{d};
    $u[$i] = $_{u};
    $sequential_id[$i] = $_{i};
    $node_id[$i] = $_{n};
    $severity[$i] = $_{s};
    $source[$i] = $_{t};
  } else { die "invalid element: $eltype"; }
}
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So what am I doing wrong?

Wait! This isn't a Parachute, this is a Backpack!