Errors appear at system startup if /www/logs is not writable. Besides, I think it makes sense to make /www directory writable at runtime. //Chen Qi
Even if we move the log location to /var/log/xxx, it will not make the situation any better, as the /www directory is still not writable. So I think, at this point, we should not do too much. I'll assume that if the user is using a read-only rootfs and his system is holding a website, maybe he'll just mount some writable media to /www.