title: how to fix message "Strict standards: Only variables should be passed by reference"
body: <p>i do not know how to fix this message that appears on line with $newfilename = uniqid() ... :</p>
  
  <pre><code>$allowedExts = array("gif", "jpeg", "jpg", "png", "zip", "html", "htm",  "js", "css", "less", "txt", "php");
  $temp = explode(".", $_FILES["file"]["name"]);
  $extension = end($temp);
  
  // skipped
  
  echo // here the echo's
  
  $newfilename = uniqid().".".end(explode(".",$_FILES["file"]["name"]));
    move_uploaded_file($_FILES["file"]["tmp_name"], "uploads/" .     $newfilename);
    // het pad naar het bestand dat geupload is; ervan uitgaande dat de map uploads in de root staat
    echo 'Url: ' . '&lt;b&gt;http://www.jouwwebsite.nl/uploads/' .    $newfilename.'&lt;/b&gt;';
    echo '&lt;br /&gt;&lt;br /&gt;';
  }
  // skipped...
  </code></pre>