<?xml version="1.0"?> <!DOCTYPE para PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN" "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"> <para> The <option>-a</option> option on the <acronym>UNIX</acronym><command>ls</command> command or the <option>/r</option> option on the <acronym>DOS</acronym><command>attrib</command> command, for example. </para>