+Send a signal to the L<lei-daemon(8)>. C<SIGNAL> defaults to C<TERM>.
+
+This command should be run after updating the code of lei.
+
+=head1 SIGNALS
+
+=over 8
+
+=item SIGTERM
+
+Send a graceful termination signal. L<lei-daemon(8)> will exit
+when all currently running lei commands are done. The listen
+socket will be released as soon as the signal is processed
+so another L<lei-daemon(8)> process can take its place.
+
+=item SIGKILL
+
+Kills L<lei-daemon(8)> immediately. Some worker processes may
+remain running after a short while after this takes effect.
+
+=back
+
+=for comment
+SIGQUIT and SIGINT currently do what SIGTERM do, may change...