Open xml file with error message.

qstream

@@ -353,7 +353,7 @@ sub end_xml{
     my ($date,$time)  = &get_date_time();
     $filename = $opt_xml;
     $filename = $date."_".$time.".xml" if $opt_xml eq "date_time";
-    open (MYFILE, '>'.$filename);
+    open (MYFILE, '>'.$filename) || die "Could not open $filename : $!";
     my $final_xml = $doc->toString();
     $twig->parse($final_xml);
     $twig->flush(\*MYFILE);