Send packet continuously over nus

[Fiske]

Is it OK  to send multiple packet continuously over nus at below way without waiting for packet transmit complete?

      i=UserUart.RxBuf[1]+2;
           index = 0;
           while(i>0)
           {
             if(i>20)
             {
               err_code = ble_nus_string_send(&m_nus, UserUart.RxBuf+index, 20);
               if (err_code != NRF_ERROR_INVALID_STATE)
               {
                   APP_ERROR_CHECK(err_code);
               }
               i -= 20;
               index += 20;
             }
             else 
             {
               err_code = ble_nus_string_send(&m_nus, UserUart.RxBuf+index, i);
               if (err_code != NRF_ERROR_INVALID_STATE)
               {
                   APP_ERROR_CHECK(err_code);
               }
               i = 0;
               
             }
               
           }

[Fiske]

Can I modify the code to below? Can below code make sure that all packet are deliveried

  i=UserUart.RxBuf[1]+2;
       index = 0;
       while(i>0)
       {
         if(i>20)
         {
           while((err_code = ble_nus_string_send(&m_nus, UserUart.RxBuf+index, 20)) ==BLE_ERROR_NO_TX_PACKETS)
           {           
                      ;
           }
           if (err_code != NRF_ERROR_INVALID_STATE)
           {
               APP_ERROR_CHECK(err_code);
           }
           i -= 20;
           index += 20;
         }
         else 
         {
           while((err_code = ble_nus_string_send(&m_nus, UserUart.RxBuf+index, i))====BLE_ERROR_NO_TX_PACKETS) 
            {

                         ;
            }
           if (err_code != NRF_ERROR_INVALID_STATE)
           {
               APP_ERROR_CHECK(err_code);
           }
           i = 0;

         }

       }