Interop\Async\Loop\Driver::onWritable PHP Method

onWritable() abstract public method

Warning: Closing resources locally, e.g. with fclose, might not invoke the callback. Be sure to cancel the watcher when closing the resource locally. Drivers MAY choose to notify the user if there are watchers on invalid resources, but are not required to, due to the high performance impact. Watchers on closed resources are therefore undefined behavior. Multiple watchers on the same stream MAY be executed in any order.

abstract public onWritable ( resource $stream, callable $callback, mixed $data = null ) : string
$stream	resource	The stream to monitor.
$callback	callable
$data	mixed	Arbitrary data given to the callback function as the `$data` parameter.
return	string	An unique identifier that can be used to cancel, enable or disable the watcher.