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update_(meta_type)_metadata filter-hook . WP 3.1.0

Filters whether to update metadata of a specific type.

The dynamic portion of the hook, $meta_type, refers to the meta object type (comment, post, term, or user). Returning a non-null value will effectively short-circuit the function.

Usage

add_filter( 'update_(meta_type)_metadata', 'filter_function_name_3209', 10, 5 );
function filter_function_name_3209( $check, $object_id, $meta_key, $meta_value, $prev_value ){
	// filter...

	return $check;
}
$check(null/true/false)
Whether to allow updating metadata for the given type.
$object_id(int)
Object ID.
$meta_key(string)
Meta key.
$meta_value(mixed)
Meta value. Must be serializable if non-scalar.
$prev_value(mixed)
Optional. If specified, only update existing metadata entries with the specified value. Otherwise, update all entries.

Where the hook is called

update_metadata()
wp-includes/meta.php 191
$check = apply_filters( "update_{$meta_type}_metadata", null, $object_id, $meta_key, $meta_value, $prev_value );

Where the hook is used (in WP core)

wp-includes/default-filters.php 103
add_filter( 'update_term_metadata', 'wp_check_term_meta_support_prefilter' );