Php/docs/class.event

• PHP Manual
• Event
• The Event class

(PECL event >= 1.2.6-beta)

Introduction

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

final Event {

/* Constants */

const int ET = 32

const int PERSIST = 16

const int READ = 2

const int WRITE = 4

const int SIGNAL = 8

const int TIMEOUT = 1

/* Properties */

public readonly bool $pending

/* Methods */

public add ([ float $timeout ] ) : bool

public addSignal ([ float $timeout ] ) : bool

public addTimer ([ float $timeout ] ) : bool

public __construct ( EventBase $base , mixed $fd , int $what , callable $cb [, mixed $arg = NULL ] )

public del ( ) : bool

public delSignal ( ) : bool

public delTimer ( ) : bool

public free ( ) : void

public static getSupportedMethods ( ) : array

public pending ( int $flags ) : bool

public set ( EventBase $base , mixed $fd [, int $what [, callable $cb [, mixed $arg ]]] ) : bool

public setPriority ( int $priority ) : bool

public setTimer ( EventBase $base , callable $cb [, mixed $arg ] ) : bool

public static signal ( EventBase $base , int $signum , callable $cb [, mixed $arg ] ) : Event

public static timer ( EventBase $base , callable $cb [, mixed $arg ] ) : Event

}

Properties

pending

Whether event is pending. See About event persistence .

Predefined Constants

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 .

Event::PERSIST

Indicates that the event is persistent. See About event persistence .

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.

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.

Event::SIGNAL

Used to implement signal detection. See "Constructing signal events" below.

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.

Table of Contents

• Event::add — Makes event pending
• Event::addSignal — Makes signal event pending
• Event::addTimer — Makes timer event pending
• Event::__construct — Constructs Event object
• Event::del — Makes event non-pending
• Event::delSignal — Makes signal event non-pending
• Event::delTimer — Makes timer event non-pending
• Event::free — Make event non-pending and free resources allocated for this event
• Event::getSupportedMethods — Returns array with of the names of the methods supported in this version of Libevent
• Event::pending — Detects whether event is pending or scheduled
• Event::set — Re-configures event
• Event::setPriority — Set event priority
• Event::setTimer — Re-configures timer event
• Event::signal — Constructs signal event object
• Event::timer — Constructs timer event object