Description
Schedules a hook which will be triggered by WordPress at the specified interval. The action will trigger when someone visits your WordPress site if the scheduled time has passed.
Valid values for the recurrence are ‘hourly’, ‘daily’, and ‘twicedaily’. These can be extended using the ‘cron_schedules’ filter in wp_get_schedules().
Note that scheduling an event to occur within 10 minutes of an existing event with the same action hook will be ignored unless you pass unique $args values for each scheduled event.
Use wp_next_scheduled() to prevent duplicate events.
Use wp_schedule_single_event() to schedule a non-recurring event.
Source
File: wp-includes/cron.php
function wp_schedule_event( $timestamp, $recurrence, $hook, $args = array() ) {
// Make sure timestamp is a positive integer.
if ( ! is_numeric( $timestamp ) || $timestamp <= 0 ) {
return false;
}
$schedules = wp_get_schedules();
if ( ! isset( $schedules[ $recurrence ] ) ) {
return false;
}
$event = (object) array(
'hook' => $hook,
'timestamp' => $timestamp,
'schedule' => $recurrence,
'args' => $args,
'interval' => $schedules[ $recurrence ]['interval'],
);
/** This filter is documented in wp-includes/cron.php */
$pre = apply_filters( 'pre_schedule_event', null, $event );
if ( null !== $pre ) {
return $pre;
}
/** This filter is documented in wp-includes/cron.php */
$event = apply_filters( 'schedule_event', $event );
// A plugin disallowed this event.
if ( ! $event ) {
return false;
}
$key = md5( serialize( $event->args ) );
$crons = _get_cron_array();
$crons[ $event->timestamp ][ $event->hook ][ $key ] = array(
'schedule' => $event->schedule,
'args' => $event->args,
'interval' => $event->interval,
);
uksort( $crons, 'strnatcasecmp' );
return _set_cron_array( $crons );
}