res_irecv = MSG_task_isend(MSG_task_create(NULL, 0, 0, NULL), mailbox);
MSG_comm_wait(res_irecv, -1);
MSG_comm_destroy(res_irecv);
res_irecv = MSG_task_isend(MSG_task_create(NULL, 0, 0, NULL), mailbox);
MSG_comm_wait(res_irecv, -1);
MSG_comm_destroy(res_irecv);