Manual:$wgHooks

Details
Global list of hooks. It is an array of arrays: it specifies for every event an array of functions to be called.

In MW 1.40, the use of $wgHooks after initialisation was deprecated (T331602). Use instead.

Add a hook by doing:

or:

or:

or:

In the last case, the callback is expected to be a method in $object of the same name as the event preceded by "on", e.g. "onUnknownAction"