+The following log items are only available when running in extended
+mode, requested by the *-e* option, as described above. If unavailable
+due to not running in extended mode, each of the log items below will
+instead expand into a dash.
+
+*%c*::
+
+ Expands into the HTTP status code of the response.
+
+*%i*::
+
+ Expands into the number of bytes sent by the client as a
+ request-body. HTTP headers are not counted.
+
+*%o*::
+
+ Expands into the number of bytes sent back by the handler, to
+ the client, as the response-body. HTTP headers are not
+ counted, and neither are overhead as part of any required
+ transfer-encoding, such as chunking.
+
+*%d*::
+
+ Expands into the time it took for the handler to complete the
+ response, expressed as seconds with 6 decimals precision.
+