#!/bin/sh
ua="$(yt-dlp --dump-user-agent)"

test -z "${url:=$1}" &&
	url="$(cat /dev/stdin)"

url="http://youtube.com/$(echo "$url" |
	awk -F '/' '{print $NF}')"
echo "url: $url" >&2

curl -L -s -H "$ua" "$url" |
	pup 'link[title=RSS] attr{href}'