%...r: First line of request
%...s: Status. For requests that got internally redirected, this
is status of the *original* request --- %...>s for the last.
-%...t: Time, in common log format time format
+%...t: Time, in common log format time format (standard english format)
%...{format}t: The time, in the form given by format, which should
- be in strftime(3) format.
+ be in strftime(3) format. (potentially localised)
%...T: The time taken to serve the request, in seconds.
%...u: Remote user (from auth; may be bogus if return status (%s) is 401)
%...U: The URL path requested.