Change php error reporting to hide warnings for specific site only [Debian|Ubuntu]

If you have access to the apache vhost configurations, of course you can also use php_flag directives inside a Virtual Host in the sites-available directory. This way, they're only applied to this vhost.

Add something like this inside your Virtual Host:

<IfModule mod_php5.c>
    php_admin_flag display_errors off
</IfModule>

EDIT:

If you want only actual errors displayed, you can use the php directive error_reporting with an integer value that describes the types of error levels you want to be displayed:

<IfModule mod_php5.c>
    php_admin_flag display_errors on
    php_admin_value error_reporting 22517
</IfModule>

This is equivalent to a setting of

error_reporting = E_ALL & ~E_NOTICE & ~E_WARNING & ~E_STRICT & ~E_DEPRECATED;

in php.ini. More possible values for example here:

https://web.archive.org/web/20131009000719/http://www.websitefactors.co.uk/php/2013/01/php-error-reporting-settings

Error reporting value calculator:

http://www.bx.com.au/tools/ultimate-php-error-reporting-wizard