TM4C129ENCPDT: sending missing data using memcpy function

The problem was about databuffer[6]=0 . so when trying to send data, when it encounters to 6. byte. it just stop sending. that is why other data are missing. How to avoid this problem?because 0 value should be inside the buffer. if you have advice or idea, please let me know

thank you

Bekir

static err_t tcp_echoclient_connected(void *arg, struct tcp_pcb *tpcb, err_t err)
{
    struct echoclient *es = NULL;
    uint16_t index2;
    if (err == ERR_OK)
    {
        /* allocate structure es to maintain tcp connection informations */
        es = (struct echoclient *)mem_malloc(sizeof(struct echoclient));

        if (es != NULL)
        {
            es->state = ES_CONNECTED;
            es->pcb = tpcb;

            if(ETH_Ctrl.connectTYPE == ETHERNET_POST)
            {
                memcpy(data,Gateway.tcp_message,Gateway.tcp_message_length);

                es->p_tx = pbuf_alloc(PBUF_TRANSPORT, 792 , PBUF_POOL);

                if (es->p_tx)
                {
                    /* copy data to pbuf */
                    pbuf_take(es->p_tx, (char*)data, strlen((char*)data));

                    /* pass newly allocated es structure as argument to tpcb */
                    tcp_arg(tpcb, es);

                    /* initialize LwIP tcp_recv callback function */
                    tcp_recv(tpcb, tcp_echoclient_recv);

                    /* initialize LwIP tcp_sent callback function */
                    tcp_sent(tpcb, tcp_echoclient_sent);

                    /* initialize LwIP tcp_poll callback function */
                    tcp_poll(tpcb, tcp_echoclient_poll, 1);

                    /* send data */
                    tcp_echoclient_send(tpcb,es);

                    return ERR_OK;
                }
            }
            else if(ETH_Ctrl.connectTYPE == NTP_CONNECT)
            {
                memset(data,0,sizeof(data));

                /* allocate pbuf */
                es->p_tx = pbuf_alloc(PBUF_TRANSPORT, strlen((char*)data) , PBUF_POOL);

                if (es->p_tx)
                {
                    /* copy data to pbuf */
                    pbuf_take(es->p_tx, (char*)data, strlen((char*)data));

                    /* pass newly allocated es structure as argument to tpcb */
                    tcp_arg(tpcb, es);

                    /* initialize LwIP tcp_recv callback function */
                    tcp_recv(tpcb, tcp_echoclient_recv);

                    /* initialize LwIP tcp_sent callback function */
                    tcp_sent(tpcb, tcp_echoclient_sent);

                    /* initialize LwIP tcp_poll callback function */
                    tcp_poll(tpcb, tcp_echoclient_poll, 1);

                    /* send data */
                    tcp_echoclient_send(tpcb,es);

                    ETH_Ctrl.status = ETH_STATUS_NTP_CONNECTED;

                    return ERR_OK;
                }
            }
        }
        else
        {
            /* close connection */
            tcp_echoclient_connection_close(tpcb, es);

            /* return memory allocation error */
            return ERR_MEM;
        }
    }
    else
    {
        /* close connection */
        tcp_echoclient_connection_close(tpcb, es);
    }
    return err;
}

I guess it happens something in es->p_tx = pbuf_alloc(PBUF_TRANSPORT, 792 , PBUF_POOL).

When I am checking by using debug mode, after passing pbuf_alloc command, tot_len which is normally 792 byte become 779 byte. When I look at the data buffer , I see that 779. byte is zero as you can see below.  So I thought that program understand null when it encounter zero. thus it stops putting data new buffer. thus length of new buffer become 779 . I guess this happening in pbuf_alloc function. But I cant find where it is happening

Hi Bruce,

  Thanks for your insight.  You are correct that the strlen function will only computes the length of the string up to, but not including the terminating null character. 

thank you. that was correct.