Php – Trouble enabling display_error in php.ini

I'm trying to enable PHP error output to the browser. phpinfo() shows that the path to php.ini is /etc/httpd/php.ini. So as root I edited it by adding a line:

display_errors = On

I restarted apache and it still didn't work, phpinfo() was showing that display_errors was Off both as local and master values. I rebooted my computer and the problem was still there.

If I add

ini_set("display_errors","1");
ERROR_REPORTING(E_ALL);

to my script it shows the errors, phpinfo() shows that display_errors as local value is On, but I'd like to find out why the php.ini solution isn't working. I don't know if it's relevant, but here's the permission settings to php.ini:

-rw-r--r--  1 root root 48267 Oct 10 00:22 php.ini