How do I turn off PHP Notices?

Notice: Constant DIR_FS_CATALOG already defined

I've already commented out display_errors in php.ini, but is not working.

How do I make PHP to not output such things to browsers?

UPDATE

I put display_errors = Off there but it's still reporting such notices,

Is this an issue with PHP 5.3?

Reporting numerous Call Stack too..

Solution

You can disable notices by setting error reporting level to E_ALL & ~E_NOTICE; using either error_reporting ini setting or the error_reporting() function.

However, notices are annoying (I can partly sympathize) but they serve a purpose. You shouldn't be defining a constant twice, the second time won't work and the constant will remain unchanged!