rmc_comm_dp_msend
err = rmc_comm_dp_msend(rcs, &ctlmsg);
err = rmc_comm_dp_msend(rcs, &req);
while ((err = rmc_comm_dp_msend(rcs, &req)) == RCNOERR) {
int rmc_comm_dp_msend(struct rmc_comm_state *, dp_message_t *);