smx_action_t SIMIX_rdv_get_head(smx_rdv_t rdv);
smx_action_t SIMIX_comm_isend(smx_process_t src_proc, smx_rdv_t rdv,
double task_size, double rate,
smx_action_t SIMIX_rdv_get_head(smx_rdv_t rdv);
smx_action_t SIMIX_comm_isend(smx_process_t src_proc, smx_rdv_t rdv,
double task_size, double rate,