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action is not described

wp_trash_post action-hook . WP 3.3.0

Fires before a post is sent to the trash.

Usage

add_action( 'wp_trash_post', 'action_function_name_9713' );
function action_function_name_9713( $post_id ){
	// action...
}
$post_id(int)
Post ID.

Where the hook is called

wp_trash_post()
WP_Customize_Manager::trash_changeset_post()
wp-includes/post.php 2820
do_action( 'wp_trash_post', $post_id );
wp-includes/class-wp-customize-manager.php 2954
do_action( 'wp_trash_post', $post_id );

Where the hook is used (in WP core)

wp-includes/default-filters.php 463
add_action( 'wp_trash_post', '_reset_front_page_settings_for_post' );