function read_file( $file, $defaultfile='' ) {

	// open the HTML file and read it into $html
	if (file_exists( $file )) {
		$html_file = fopen( $file, "r" );
	}
	elseif( !empty( $defaultfile ) && file_exists( $defaultfile ) ) {
		$html_file = fopen( $defaultfile, "r" );
	}
	else {
		return;
	}
	$html = "";

	while (!feof($html_file)) {
		$buffer = fgets($html_file, 1024);
		$html .= $buffer;
	}
	fclose ($html_file);

	return( $html );
}