gentoo-overlay/app-cdr/disc-cover/metadata.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE pkgmetadata SYSTEM "http://www.gentoo.org/dtd/metadata.dtd">
<pkgmetadata>
  <longdescription>
    This is the disc-cover CLI only. For the web application,
    see www-apps/disc-cover. These two packages are tightly
    bound by the fact that they come from the same source package.
    That's why the web application ebuild is manually slotted to 0.
  </longdescription>
  <use>
	  <flag name="cdrom">Enable audio CD support. This is not needed to make
		  www-apps/disc-cover work.</flag>
  </use>
</pkgmetadata>