gentoo-overlay/app-doc/tldp-howto/metadata.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE pkgmetadata SYSTEM "http://www.gentoo.org/dtd/metadata.dtd">
<pkgmetadata>
	<herd>app-doc</herd>
	<use>
		<flag name='html'>Install multi-chapter HTML docs</flag>
		<flag name='htmlsingle'>Install all-on-one-page HTML docs</flag>
		<flag name='pdf'>Install pdf docs</flag>
		<flag name='text'>Install plain-text docs</flag>
	</use>
</pkgmetadata>