wp_clear_scheduled_hook( string $hook, array $args = array(), bool $wp_error = false ): int|false|WP_Error

Description

Compatibility

Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.

Parameters

$hookstring

Action hook, the execution of which will be unscheduled.

$argsarrayoptional

Array containing each separate argument to pass to the hook's callback function.
Although not passed to a callback, these arguments are used to uniquely identify the event, so they must match those used when originally scheduling the event. If the arguments do not match exactly, the event will not be found. Default empty array.Default: array()

$wp_errorbooloptional

Whether to return a WP_Error on failure. Default false.Default: false

Return value

int|false|WP_Error

On success an integer indicating number of events unscheduled (0 indicates no events were registered with the hook and arguments combination), false or WP_Error if unscheduling one or more events fail.

Performance profile

How much work a call to wp_clear_scheduled_hook() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.

Cost class

Heavy

Reads stored settings via get_option(), cached per request but not free on a cold cache.

Scaling

Scales with input

The body loops, so the work grows with what you pass in.

Instructions

20–59

Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 94.

Plugin surface

1 hook

Third-party callbacks on 'pre_clear_scheduled_hook' run inside this call, and their cost is not bounded by anything here.

Called by

9

9 places in core call this, so the cost is paid more often than your own code shows.

What it touches

• hookthird-party callbacksapply_filters()called directly
• serializeserialisationserialize()called directly
• optionoption read or writeget_option()one call below wp_clear_scheduled_hook()

Further down the call graph this can also reach cache, query and transient. Those are the worst case, several calls deep and usually down an error path, not what a normal call pays.

What one call costs · 10 distinct outcomes

One number would be a lie: the work depends on which branch runs. These are every distinct cost wp_clear_scheduled_hook() can have, taken from its control-flow graph on PHP 8.5.

Hooks and filters fired · 1

One hook fires while wp_clear_scheduled_hook() runs, in this order:

1. 1
   apply_filters( pre_clear_scheduled_hook )filterline 610 (+34 into the body)

   Filter to override clearing a scheduled hook.

Uses · 7

• _deprecated_argument()Marks a function argument as deprecated and inform when it has been used.
• __()Retrieves the translation of $text.
• apply_filters()Calls the callback functions that have been added to a filter hook.
• is_wp_error()Checks whether the given variable is a WordPress Error.
• _get_cron_array()Retrieves cron info array option.
• wp_unschedule_event()Unschedules a previously scheduled event.
• WP_Error::__construct()Initializes the error.

Used by · 9

• _future_post_hook()Hook used to schedule publication for a post marked for the future.
• _transition_post_status()Hook for managing future post transitions to published.
• check_and_publish_future_post()Publishes future post and make sure post ID has future post status.
• populate_network()Populate network settings.
• upgrade_370()Execute changes made in WordPress 3.7.
• upgrade_372()Execute changes made in WordPress 3.7.2.
• upgrade_450()Executes changes made in WordPress 4.5.0.
• upgrade_640()Executes changes made in WordPress 6.4.0.
• wp_delete_post()Trashes or deletes a post or page.

Source code

View on Trac ↗View on GitHub ↗

576function wp_clear_scheduled_hook( $hook, $args = array(), $wp_error = false ) {577	/*578	 * Backward compatibility.579	 * Previously, this function took the arguments as discrete vars rather than an array like the rest of the API.580	 */581	if ( ! is_array( $args ) ) {582		_deprecated_argument(583			__FUNCTION__,584			'3.0.0',585			__( 'This argument has changed to an array to match the behavior of the other cron functions.' )586		);587 588		$args     = array_slice( func_get_args(), 1 ); // phpcs:ignore PHPCompatibility.FunctionUse.ArgumentFunctionsReportCurrentValue.NeedsInspection589		$wp_error = false;590	}591 592	/**593	 * Filter to override clearing a scheduled hook.594	 *595	 * Returning a non-null value will short-circuit the normal unscheduling596	 * process, causing the function to return the filtered value instead.597	 *598	 * For plugins replacing wp-cron, return the number of events successfully599	 * unscheduled (zero if no events were registered with the hook) or false600	 * or a WP_Error if unscheduling one or more events fails.601	 *602	 * @since 5.1.0603	 * @since 5.7.0 The `$wp_error` parameter was added, and a WP_Error object can now be returned.604	 *605	 * @param null|int|false|WP_Error $pre      Value to return instead. Default null to continue unscheduling the event.606	 * @param string                  $hook     Action hook, the execution of which will be unscheduled.607	 * @param array                   $args     Arguments to pass to the hook's callback function.608	 * @param bool                    $wp_error Whether to return a WP_Error on failure.609	 */610	$pre = apply_filters( 'pre_clear_scheduled_hook', null, $hook, $args, $wp_error );611 612	if ( null !== $pre ) {613		if ( $wp_error && false === $pre ) {614			return new WP_Error(615				'pre_clear_scheduled_hook_false',616				__( 'A plugin prevented the hook from being cleared.' )617			);618		}619 620		if ( ! $wp_error && is_wp_error( $pre ) ) {621			return false;622		}623 624		return $pre;625	}626 627	/*628	 * This logic duplicates wp_next_scheduled().629	 * It's required due to a scenario where wp_unschedule_event() fails due to update_option() failing,630	 * and, wp_next_scheduled() returns the same schedule in an infinite loop.631	 */632	$crons = _get_cron_array();633	if ( empty( $crons ) ) {634		return 0;635	}636 637	$results = array();638	$key     = md5( serialize( $args ) );639 640	foreach ( $crons as $timestamp => $cron ) {641		if ( isset( $cron[ $hook ][ $key ] ) ) {642			$results[] = wp_unschedule_event( $timestamp, $hook, $args, true );643		}644	}645 646	$errors = array_filter( $results, 'is_wp_error' );647	$error  = new WP_Error();648 649	if ( $errors ) {650		if ( $wp_error ) {651			array_walk( $errors, array( $error, 'merge_from' ) );652 653			return $error;654		}655

Changelog

Introduced in 2.1.0. Unchanged from 6.7.7 through 7.1.0.

1. 6.7.7
2. 6.8.8
3. 6.9.7
4. 7.0.4
5. 7.1.0

Signature, return type and hooks compared across 5 parsed releases.

About this page

Parsed data

Generated from the wordpress-develop 7.1.0 tag, from src/wp-includes/cron.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.

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