Plugin: List wp cron jobs in wp_footer

cron-list.php

<?php
defined( 'ABSPATH' ) OR exit;
/*
Plugin Name: WP Cron Jobs List
Plugin URI:  https://github.com/franz-josef-kaiser
Description: List WordPress internal cron jobs (array data) after the footer.
Author:      Franz Josef Kaiser
Author URI:  https://github.com/franz-josef-kaiser
Version:     0.3.1
License:     MIT
*/

add_action ( 'shutdown', 'wpse18017_list_cron' );
/**
 * Builds a table to list current wp internal cron job data
 * 
 * @param  mixed array $cron_arr
 * @return string
 */
function wpse18017_list_cron( $cron_arr )
{
	// Load cron jobs and flatten array
	foreach ( _get_cron_array() as $key => $data )
	{
		if ( is_int( $key ) )
		{
			if ( 1 <= count( $data ) )
			{
				foreach ( $data as $k => $d )
				{
					$v = array_values( current( $d ) );
					$cron_jobs[ $k ] = $v;
				}
				continue;
			}
			$val = array_values( current( $data ) );
			$cron_jobs[ key( $data ) ] = $val[0];
		}
	}

	// Nothing to do
	if ( empty( $cron_jobs ) )
		return;

	$results = '';
	foreach ( $cron_jobs as $name => $data )
	{
		list ( $schedule, $args, $interval ) = wp_parse_args(
			array_fill( 0, 3, 'not-set' ),
			$data
		);
		$args = var_export( $args, true );
		foreach ( wp_get_schedules() as $l10n )
		{
			if ( $interval === $l10n['interval'] )
			{
				$schedule = $l10n['display'];
				$interval = ( $interval /60 /60 );
			}
		}
		$results .= "<tr><td>{$name}</td><td>{$args}</td><td>{$schedule}</td><td>{$interval}</td></tr>";
	}

	echo <<< EOF
<div class="clear"></div>
<div class="wrap">
	<table class="wp-list-table widefat" style="margin: 10px;">
		<caption>Dump of the cron/sheduled events:</caption>
		<tr><th>Function</th><th>Arguments</th><th>Shedule</th><th>Time (h)</th></tr>
		$results
	</table>
</div>
EOF;
}