# Zookeeper::setWatcher

(PECL zookeeper >= 0.1.0)

Zookeeper::setWatcher — Set a watcher function

### Descripción

public Zookeeper::setWatcher(callable `$watcher_cb`): bool

### Parámetros

`watcher_cb`

  A watch will be set at the server to notify the client if the node changes.

### Valores devueltos

Devuelve `true` en caso de éxito o `false` en caso de error.

### Errores/Excepciones

This method emits PHP error/warning when parameters count or types are wrong or fail to set watcher.

Precaución

Since version 0.3.0, this method emits ZookeeperException and it's derivatives.

### Ver también

- Zookeeper::exists() - Checks the existence of a node in zookeeper synchronously
- Zookeeper::get() - Gets the data associated with a node synchronously
- ZookeeperException