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function is not described

wp_shortlink_wp_head() WP 3.0.0

Injects rel=shortlink into the head if a shortlink is defined for the current page.

Attached to the 'wp_head' action.

No Hooks.

Return

Nothing (null).

Usage

wp_shortlink_wp_head();

Code of wp shortlink wp head: wp-includes/link-template.php VER 5.0.3

<?php
function wp_shortlink_wp_head() {
	$shortlink = wp_get_shortlink( 0, 'query' );

	if ( empty( $shortlink ) )
		return;

	echo "<link rel='shortlink' href='" . esc_url( $shortlink ) . "' />\n";
}