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action is not described

added_(meta_type)_meta action-hook . WP 2.9.0

Fires immediately after meta of a specific type is added.

The dynamic portion of the hook, $meta_type, refers to the meta object type (comment, post, term, or user).

Usage

add_action( 'added_(meta_type)_meta', 'action_function_name_3839', 10, 4 );
function action_function_name_3839( $mid, $object_id, $meta_key, $meta_value ){
	// action...
}
$mid(int)
The meta ID after successful update.
$object_id(int)
Object ID.
$meta_key(string)
Meta key.
$meta_value(mixed)
Meta value.

Where the hook is called

add_metadata()
wp-includes/meta.php 124
do_action( "added_{$meta_type}_meta", $mid, $object_id, $meta_key, $_meta_value );

Where the hook is used (in WP core)

wp-includes/default-filters.php 93
add_action( 'added_post_meta', 'wp_cache_set_posts_last_changed' );
wp-includes/default-filters.php 98
add_action( 'added_term_meta', 'wp_cache_set_terms_last_changed' );
wp-includes/default-filters.php 111
add_action( 'added_comment_meta', 'wp_cache_set_comments_last_changed' );