This plugin provides the <txp:rvm_article_edit /> and <txp:rvm_edit_comment /> tags, which show links to the edit page of the currently visited article or comment respectively, but only for visitors who are logged in on the admin side of Textpattern.
<txp:rvm_edit_article /><txp:rvm_edit_article>your link text</txp:rvm_edit_article><txp:rvm_edit_comment /><txp:rvm_edit_comment>your link text</txp:rvm_edit_comment>