# The EvChild class

(PECL ev >= 0.2.0)

## Introducción

EvChild watchers trigger when the process receives a `SIGCHLD` in response to some child status changes (most typically when a child dies or exits). It is permissible to install an `EvChild` watcher after the child has been forked(which implies it might have already exited), as long as the event loop isn't entered(or is continued from a watcher), i.e. forking and then immediately registering a watcher for the child is fine, but forking and registering a watcher a few event loop iterations later or in the next callback invocation is not.

It is allowed to register EvChild watchers in the default loop only.

## Sinopsis de la Clase

class EvChild extends EvWatcher {
/* Propiedades */
public $pid;
public $rpid;
public $rstatus;
/* Propiedades heredadas */
public $is_active;
public $data;
public $is_pending;
public $priority;
/* Métodos */
public __construct(
int `$pid` ,
bool `$trace` ,
callable `$callback` ,
mixed `$data` = `null` ,
int `$priority` = 0
)
final public static createStopped(
int `$pid` ,
bool `$trace` ,
callable `$callback` ,
mixed `$data` = ?,
int `$priority` = ?
): object
public set( int `$pid` , bool `$trace` ): void
/* Métodos heredados */
public EvWatcher::clear(): int
public EvWatcher::feed( int `$revents` ): void
public EvWatcher::getLoop(): EvLoop
public EvWatcher::invoke( int `$revents` ): void
public EvWatcher::keepalive( bool `$value` = ?): bool
public EvWatcher::setCallback( callable `$callback` ): void
public EvWatcher::start(): void
public EvWatcher::stop(): void
}

## Propiedades

pid

  Readonly . The process ID this watcher watches out for, or `0` , meaning any process ID.

rpid

  Readonly .The process ID that detected a status change.

rstatus

  Readonly . The process exit status caused by rpid .

## Tabla de contenidos

- EvChild::__construct — Constructs the EvChild watcher object
- EvChild::createStopped — Create instance of a stopped EvCheck watcher
- EvChild::set — Configures the watcher