Вот код:

<form method="POST" action="" >
Введите адрес сайта:<br>
<input type="text" name="url" id="url" value="" > 
<input type="submit" name="go" value=" пуск " >
</form>


<?php
header("Content-Type: text/html; charset=utf-8");
$url = $POST_['url'];
if (isset($url))   {

include '/functions/timezag.php';
include '/functions/nalsitemap.php';
include '/functions/nalrobots.php';
include '/functions/nalfavicon.php';
$timezag = function timezag ($url);
$nalsitemap = function nalsitemap ($url);
$nalrobots = function nalrobots ($url);
$nalfavicon = function nalfavicon ($url);



echo '
      <center>Время загрузки сайта: '.$timezag.'<center><br>
	  <center>Наличие robots.txt: '.$nalrobots.'  <center><br>
	  <center>Наличие sitemap.xml: '.$nalsitemap.'  <center><br>
	  <center>Наличие favicon.ico: '.$nalfavicon.'  <center><br>
	  
	  ';
}
?>

А вот что он выводет:
Warning: Unknown: failed to open stream: No such file or directory in Unknown on line 0

( ! ) Warning: Unknown: failed to open stream: No such file or directory in Unknown on line 0

( ! ) Fatal error: Unknown: Failed opening required 'D:/OpenServer/domains/localhost/скрипт анализа/analiz.php' (include_path='.;D:\OpenServer\modules\php\PHP-5.4.26;D:\OpenServer\modules\php\PHP-5.4.26\PEAR\pear') in Unknown on line 0