Event callbacks
If a callback is registered for an event, it will be called when the event becomes active. To associate a callback with event one can pass a callable to either Event::__construct() , or Event::set() , or one of the factory methods like Event::timer() .
An event callback should match the following prototype:
-
fd -
The file descriptor, stream resource or socket associated with the event. For signal event
fdis equal to the signal number. -
what -
Bit mask of all events triggered.
-
arg -
User custom data.
Event::timer() expects the callback to match the following prototype:
-
arg -
User custom data.
Event::signal() expects the callback to match the following prototype:
-
signum -
The number of the triggered signal(e.g.
SIGTERM). -
arg -
User custom data.
