briefly document some more C types

diff --git a/docs/source/app_s4u.rst b/docs/source/app_s4u.rst
index af35920..158148b 100644 (file)
--- a/docs/source/app_s4u.rst
+++ b/docs/source/app_s4u.rst
@@ -429,6 +429,11 @@ Creating actors
 
          #include <simgrid/actor.h>
 
+      .. doxygentypedef:: sg_actor_t
+      .. cpp:type:: const s4u_Actor* const_sg_actor_t
+
+         Pointer to a constant actor object.
+
       .. autodoxymethod:: sg_actor_init(const char *name, sg_host_t host)
       .. autodoxymethod:: sg_actor_start(sg_actor_t actor, xbt_main_func_t code, int argc, char **argv)