Deriving Location Intelligence from Complex Event Processing for National Security Ap
by Joe Francica,* Directions MagazineAs sensory information becomes more advanced, the government is faced with a continuous and ever-expanding stream of real-time information from which it collects intelligence in support of national security. Thousands of small, seemingly insignificant events happen every day. ObjectFX has created a solution that fits within Complex Event Processing.* CEP helps [...]
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)