WordPress at a glance
function is not described

next_post_rel_link() WP 2.8.0

Displays the relational link for the next post adjacent to the current post.

  • See: get_adjacent_post_rel_link()

No Hooks.

Return

Nothing (null).

Usage

next_post_rel_link( $title, $in_same_term, $excluded_terms, $taxonomy );
$title(string)
Link title format.
Default: '%title'
$in_same_term(true/false)
Whether link should be in a same taxonomy term.
Default: false
$excluded_terms(array/string)
Array or comma-separated list of excluded term IDs.
Default: ''
$taxonomy(string)
Taxonomy, if $in_same_term is true.
Default: 'category'

Code of next post rel link: wp-includes/link-template.php VER 5.0.3

<?php
function next_post_rel_link( $title = '%title', $in_same_term = false, $excluded_terms = '', $taxonomy = 'category' ) {
	echo get_adjacent_post_rel_link( $title, $in_same_term, $excluded_terms, false, $taxonomy );
}