page_ext=`echo "$content" | grep -Po "(?<=<link href=').*?(?=' rel='alternate' type='application/atom\+xml'>)" | head -1`

determine_protocol
get_domain

if [[ ! -n $page_ext ]]
then
	# blog page
	if [[ "$url" == *${domain}/~/* ]]
	then
		# get link to user page
		user_link=`echo $content | grep -Po '(?<=<a rel="author" class="u-url" href=").*?(?="></a>)' | head -1`
		if [[ -n $user_link ]]
		then
			# get Atom feed
			page_ext="${user_link%%/}/atom.xml"
		fi
	fi
fi