' .
		    htmlentities(debug_string_backtrace()) . "

";

	$divstring = "\n\n" . '\n
\n" .
	    'Click to toggle' .
	    "\n
";

	if (!($doctype = util_ifsetor($HTML->doctype))) {
		$doctype = 'transitional';
	}

	if ($sysdebug_doframe) {
		$initial = '' .
		    $sysDTDs[$doctype]['doctype'] .
		    '\n";
		$bufferstrip = strlen($initial);
		$buffer = $initial . $buffer . '';
	}

	/* cut off  (hopefully only) at the end */
	$buffer = rtrim($buffer);	/* spaces, newlines, etc. */
	$bufend = array(false, substr($buffer, -100));
	if (substr($buffer, -strlen("")) != "") {
		$bufend[0] = true;
		$ffErrors[] = array(
			'type' => "error",
			'message' => htmlentities("does not end with  tag"),
		    );
		$buffer = str_ireplace("", "", $buffer);
	} else {
		$buffer = substr($buffer, 0, -strlen(""));
	}
	$buffer = rtrim($buffer);	/* spaces, newlines, etc. */
	if (substr($buffer, -strlen("")) != "") {
		$bufend[0] = true;
		$ffErrors[] = array(
			'type' => "error",
			'message' => htmlentities("does not end with  tag"),
		    );
		$buffer = str_ireplace("", "", $buffer);
	} else {
		$buffer = substr($buffer, 0, -strlen(""));
	}
	$buffer = rtrim($buffer);	/* spaces, newlines, etc. */

	if ($bufend[0]) {
		$ffErrors[] = array(
			'type' => "info",
			'message' => "The output has ended thus: " .
			    htmlentities($bufend[1]),
		   );
	}

	/* append errors, if any */
	$has_div = false;
	foreach ($ffErrors as $msg) {
		if (!$has_div) {
			$buffer .= $divstring;
			$has_div = true;
		}
		$buffer .= "\n	
' .
		    $msg['message'] . "
";
	}

	/* generate buffer for checking */
	$cbuf = str_ireplace('http://www.w3.org/TR/xhtml1/DTD/',
	    'file://' . $dtdpath, $buffer);
	if ($has_div) {
		$cbuf .= "\n
";
	}
	$cbuf .= "\n\n";

	/* now check XHTML validity… two means */
	$valck = array();
	$appsrc = false;

	if (forge_get_config('sysdebug_xmlstarlet')) {
		/* xmlstarlet (well-formed, DTD and DOCTYPE, encoding */
		$dspec = array(
			0 => array("pipe", "r"),
			1 => array("pipe", "w"),
			2 => array("pipe", "w"),
		    );
		$xmlstarlet = proc_open("xmlstarlet val -d " .
		    escapeshellarg($dtdpath . $sysDTDs[$doctype]['dtdfile']) .
		    " -e -", $dspec, $pipes);
		$rv = 0;
		if (is_resource($xmlstarlet)) {
			fwrite($pipes[0], $cbuf);
			fclose($pipes[0]);
			$sout = stream_get_contents($pipes[1]);
			$serr = stream_get_contents($pipes[2]);
			fclose($pipes[1]);
			fclose($pipes[2]);
			$rv = proc_close($xmlstarlet);
			/* work around Debian #627158 */
			$serr = join("\n", preg_grep(
			    '/^-:[0-9]*: Entity'." 'nbsp' ".'not defined$/',
			    explode("\n", $serr), PREG_GREP_INVERT));
		} else {
			$valck[] = array(
				'msg' => "could not run xmlstarlet",
			    );
		}
		if ($rv) {
			$valck[] = array(
				'msg' => "xmlstarlet found that this document is not valid (errorlevel $rv)!",
				'extra' => $pre_tag .
				    htmlspecialchars(trim($serr .
				    "\n\n" . $sout)) . "

' .
		    htmlentities($pretext) . "