-void SIMIX_comm_start(smx_action_t action);
-void SIMIX_comm_send(smx_process_t src_proc, smx_rdv_t rdv,
- double task_size, double rate,
- void *src_buff, size_t src_buff_size,
- int (*match_fun)(void *, void *,smx_action_t), void *data,
- double timeout);