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I am getting following error:
Notice: Use of undefined constant
__DIR__- assumed'__DIR__'in /home/a2708294/public_html/firebase/index.php on line 58
Line:58
require_once __DIR__ . '/firebase.php';
require_once __DIR__ . '/push.php';
</div>
The magic constant __DIR__ was added in PHP version 5.3.0 You can check it here: http://php.net/manual/en/language.constants.predefined.php
You need to upgrade php to a newer version. Anyway you need to upgrade because you have a very old version.
If you can't upgrade php you can use dirname(__FILE__) as a hack because magic constant __FILE__ is in PHP from version 4.0.2
So your code will look like this:
require_once(dirname(__FILE__) . '/firebase.php');
require_once(dirname(__FILE__) . '/push.php');
DIR The directory of the file. If used inside an include, the directory of the included file is returned. This is equivalent to dirname(FILE). This directory name does not have a trailing slash unless it is the root directory.