problem with send_data () of TCPNet

I tried to convert the LEDClient example project to send data to my server. But the problem I have is that I can't send more than 4 bytes.

Here's my code

case TCP_STATE_CONNECT:
            if (tcp_check_send (socket_tcp) == __TRUE) { //normal
               //sendbuf = tcp_get_buf(SENDLEN);
               //sendbuf[0] = BLINKLED;
               //sendbuf[1] = p2;
               //tcp_send (socket_tcp, sendbuf, SENDLEN);
//changed code
                           sendbuf = tcp_get_buf(7);
                           sendbuf[0]=1;
                           sendbuf[1]=20;
                           sendbuf[2]=111;
                           sendbuf[3]=213;
                           sendbuf[4]=0;
                           sendbuf[5]=88;
                           sendbuf[6]=99;
                           tcp_send (socket_tcp, sendbuf, 7);

Don't know why it will not send more than 4 bytes. Anyone who does know???

If this works, then I can adopt this project to work with my RTX Kernel...