In addition to the other problems identified by other people here (e.g. account authentication information passed on the command line) the DNS readiness check is counter productive, as negative response caching caused by the very polling that the tool does will obscure the resource record's appearance, and the file existence check is a brute force mechanism that (a) spawns an entire subprocess instead of doing lstat() and (b) does not take advantage of any kqueue() or equivalent mechanism for waiting for filesystem changes.