WordPress function get_the_shortlink

functions.php

<?php
function get_the_shortlink() {
    $post_id = get_the_ID();
    if ($post_id!="") {$shortlink=home_url()."/?p=".$post_id;} else {$shortlink="";}
    return $shortlink;
}
?>

Many WordPress functions have a standard version which outputs the results directly and an additional version prefixed with get_ that returns the output - useful for adding to a string and manipulating before output.

One such exclusion is the_shortlink, which returns a short link to any page or post - there is no get_the_shortlink, so many people have to resort to just outputting the result in a FORM field for people to cut & paste.  However, here is a quick way to add the capability to your blog - simply add the this code to your theme's functions.php. Now you just need to call get_the_shortlink() from within your WordPress loop and it will return the shortlink URL.

Unlike the_shortlink it doesn't accept any parameters, but this is a quick and simple solution.