Lighttpd

If lighttpd is set to write a pid file and you do a graceful shutdown,
immediately relaunching a new lighttpd to achieve a graceful restart, the
new lighttpd overwrites the old lighttpd pidfile... but then as the old
lighttpd exits, it unlinks the new lighttpd's pidfile!

One possible fix is to unlink the pid file as soon as the socket is unbound
rather than only as lighttpd finally exits. I've attached a patch which
implements this and seems to fix the problem completely.