if(!pthread_mutex_lock(&UART_ReadMutex)){

int prevstate;

if((prevstate=uartDevReadBuf_plc_state) == FULL){

uartDevReadBuf_plc_state = LOCKED;

}

pthread_mutex_unlock(&UART_ReadMutex);

if(prevstate == FULL){

%(retrieve_code)s

/* unlock plc buffer */

uartDevReadBuf_plc_state = EMPTY;

}else{

/* No new data -> no update */

}

}