+ /** Returns whether the mailbox contains queued communications */
+ bool empty();
+
+ /** Returns the first element in the queue, or nullptr if none is there */
+ smx_activity_t front();
+
+ /** Declare that the specified process is a permanent receiver on that mailbox
+ *
+ * It means that the communications sent to this mailbox will start flowing to its host even before he does a recv().
+ * This models the real behavior of TCP and MPI communications, amongst other.
+ */
+ void setReceiver(ActorPtr process);
+
+ /** Return the process declared as permanent receiver, or nullptr if none **/
+ ActorPtr receiver();