Unable to send TCP sockets!

I have used rl-net successfully before version 7.0 ,now doing the simple job seems to be impossible! I can not send sockets here is my code,do you have any Idea what's going on wrong?

netInitialize ();
NET_ADDR myaddr = { NET_ADDR_IP4, 4510,
                    192, 168, 1, 3 };//PC IP
static int mport=4510;
tcp_send_sock = netTCP_GetSocket (tcp_cb_client);
netTCP_SetOption (tcp_send_sock, netTCP_OptionKeepAlive, 1);

for(;;)
{
    if (tcp_send_sock > 0) {
    switch (netTCP_GetState (tcp_send_sock))
                {
      case netTCP_StateUNUSED:
      case netTCP_StateCLOSED:
        // Connect to TCP socket server
        netTCP_Connect (tcp_send_sock, &myaddr, mport);
        break;

      case netTCP_StateESTABLISHED:
      {
        // Connected, send the data
        if (netTCP_SendReady (tcp_send_sock) == true)
        {
           uint8_t *sendbuf;
           sendbuf = netTCP_GetBuffer(1440);
           sendbuf[0]=55;
           netTCP_Send (tcp_send_sock, sendbuf, 1440);
        }

    }