+Environment variable overrides in effect during loading and
+reloading (SIGHUP) can be specified as C<env.NAME=VALUE> for
+all protocols.
+
+HTTP(S) listeners may also specify C<psgi=> to use a different
+C<.psgi> file for each listener.
+
+C<err=/path/to/errors.log> may be used to isolate error/debug output
+for a particular listener away from C<--stderr>.
+
+Non-HTTP(S) listeners may also specify C<out=> for logging to
+C<stdout>. HTTP(S) users are encouraged to configure
+L<Plack::Middleware::AccessLog> or
+L<Plack::Middleware::AccessLog::Timed>, instead.
+