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function is not described

get_parent_post_rel_link() WP 2.8.0

Deprecated in 3.3.0. It is no longer supported and can be removed in future releases. It is recommended to replace this function with the same one.

Get parent post relational link.

Hooks in function
Return

String.

Usage

get_parent_post_rel_link( $title );
$title(string)
Link title format.
Default: '%title'

Code of get parent post rel link: wp-includes/deprecated.php VER 5.0.3

<?php
function get_parent_post_rel_link( $title = '%title' ) {
	_deprecated_function( __FUNCTION__, '3.3.0' );

	if ( ! empty( $GLOBALS['post'] ) && ! empty( $GLOBALS['post']->post_parent ) )
		$post = get_post($GLOBALS['post']->post_parent);

	if ( empty($post) )
		return;

	$date = mysql2date(get_option('date_format'), $post->post_date);

	$title = str_replace('%title', $post->post_title, $title);
	$title = str_replace('%date', $date, $title);
	$title = apply_filters('the_title', $title, $post->ID);

	$link = "<link rel='up' title='";
	$link .= esc_attr( $title );
	$link .= "' href='" . get_permalink($post) . "' />\n";

	return apply_filters( "parent_post_rel_link", $link );
}