Description:
------------
---
From manual page: http://www.php.net/function.filter-var
---
With test script usage we'll got this:

result:
http:///path/by/path?query=124
/path/by/path?query=124

instead of false value;

my php version is "PHP 5.5.9-1ubuntu4.7 (cli) (built: Mar 16 2015 20:47:39)"

Test script:
---------------
<?php
$uri = 'http:///path/by/path?query=124';
$uri = filter_var($uri, FILTER_SANITIZE_URL, FILTER_FLAG_HOST_REQUIRED);
var_dump($uri);

$uri = '/path/by/path?query=124';
$uri = filter_var($uri, FILTER_SANITIZE_URL, FILTER_FLAG_HOST_REQUIRED);
var_dump($uri);

?>

Expected result:
----------------
Expected false value when no hostname provided and FILTER_FLAG_HOST_REQUIRED option set;