by* Claye Greene, Principal Consultant, Technology Blue, Inc. Complex event processing (CEP) continually evolves as a technology to help organizations react to various business conditions such as threats and market opportunities. CEP technologies excel at taking raw, voluminous amounts of event data, accumulating it, correlating it and aggregating it in forms that facilitate critical decision-making. Events are [...]
EVENT(3) 1 EVENT(3)The Event classINTRODUCTION
Event class represents and event firing on a file descriptor being ready to read from or write to; a file descriptor becoming ready to read
from or write to(edge-triggered I/O only); a timeout expiring; a signal occuring; a user-triggered event.
Every event is associated with EventBase . However, event will never fire until it is added (via Event::add ). An added event remains in
pending state until the registered event occurs, thus turning it to active state. To handle events user may register a callback which is
called when event becomes active. If event is configured persistent , it remains pending. If it is not persistent, it stops being pending
when it's callback runs. Event::del method deletes event, thus making it non-pending. By means of Event::add method it could be added
again.
CLASS SYNOPSIS
Event
final
Event
Constants
o const integer$Event::ET32
o const integer$Event::PERSIST16
o const integer$Event::READ2
o const integer$Event::WRITE4
o const integer$Event::SIGNAL8
o const integer$Event::TIMEOUT1
Properties
o publicreadonly bool$pending
Methods
o public bool Event::add ([double $timeout])
o public bool Event::addSignal ([double $timeout])
o public bool Event::addTimer ([double $timeout])
o public Event::__construct (EventBase $base, mixed $fd, int $what, callable $cb, [mixed $arg = NULL])
o public bool Event::del (void )
o public bool Event::delSignal (void )
o public bool Event::delTimer (void )
o public void Event::free (void )
o publicstatic array Event::getSupportedMethods (void )
o public bool Event::pending (int $flags)
o public bool Event::set (EventBase $base, mixed $fd, [int $what], [callable $cb], [mixed $arg])
o public bool Event::setPriority (int $priority)
o public bool Event::setTimer (EventBase $base, callable $cb, [mixed $arg])
o publicstatic Event Event::signal (EventBase $base, int $signum, callable $cb, [mixed $arg])
o publicstatic Event Event::timer (EventBase $base, callable $cb, [mixed $arg])
PROPERTIES
o $pending
- Whether event is pending. See About event persistence .
PREDEFINED CONSTANTS
o Event::ET - Indicates that the event should be edge-triggered, if the underlying event base backend supports edge-triggered
events. This affects the semantics of Event::READ and Event::WRITE .
o Event::PERSIST - Indicates that the event is persistent. See About event persistence .
o Event::READ - This flag indicates an event that becomes active when the provided file descriptor(usually a stream resource, or
socket) is ready for reading.
o Event::WRITE - This flag indicates an event that becomes active when the provided file descriptor(usually a stream resource, or
socket) is ready for reading.
o Event::SIGNAL - Used to implement signal detection. See "Constructing signal events" below.
o Event::TIMEOUT - This flag indicates an event that becomes active after a timeout elapses. The Event::TIMEOUT flag is ignored
when constructing an event: one can either set a timeout when event is added , or not. It is set in the $what argument to the
callback function when a timeout has occurred.
PHP Documentation Group EVENT(3)
