Since I don't know what you are trying to do, and because no links should be constructed in template itself, without first parsed through $site_sess->url() function, I'd suggest use this in the template:
<a href="<?php
global $site_sess, $user_info, $user_table_fields;
echo $site_sess->url(ROOT_PATH."member.php?".URL_USER_ID."=".$user_info[$user_table_fields['user_id']];
?>">link text</a>