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filter is not described

category_link filter-hook . WP 1.5.0

Deprecated in 2.5.0. It is no longer supported and can be removed in future releases. Use term_link instead.

Deprecated: 2.5.0 Use 'term_link' instead.

Filters the category link.

Usage

add_filter( 'category_link', 'filter_function_name_5172', 10, 2 );
function filter_function_name_5172( $termlink, $term_id ){
	// filter...

	return $termlink;
}
$termlink(string)
Category link URL.
$term_id(int)
Term ID.

Where the hook is called

get_term_link()
category_link
wp-includes/taxonomy.php 3994
$termlink = apply_filters( 'category_link', $termlink, $term->term_id );

Where the hook is used (in WP core)

Does not used.