# TCP Client example (See the README.md file in the upper level 'examples' directory for more information about examples.) The application creates a TCP socket and tries to connect to the server with predefined IP address and port number. When a connection is successfully established, the application sends message and waits for the answer. After the server's reply, application prints received reply as ASCII text, waits for 2 seconds and sends another message. ## How to use example In order to create TCP server that communicates with TCP Client example, choose one of the following options. There are many host-side tools which can be used to interact with the UDP/TCP server/client. One command line tool is [netcat](http://netcat.sourceforge.net) which can send and receive many kinds of packets. Note: please replace `192.168.0.167 3333` with desired IPV4/IPV6 address (displayed in monitor console) and port number in the following command. In addition to those tools, simple Python scripts can be found under sockets/scripts directory. Every script is designed to interact with one of the examples. ### TCP server using netcat ``` nc -l 192.168.0.167 3333 ``` ### Python scripts Script example_test.py could be used as a counter part to the tcp-client project, ip protocol name (IPv4 or IPv6) shall be stated as argument. Example: ``` python example_test.py IPv4 ``` Note that this script is used in automated tests, as well, so the IDF test framework packages need to be imported; please add `$IDF_PATH/tools/ci/python_packages` to `PYTHONPATH`. ## Hardware Required This example can be run on any commonly available ESP32 development board. ## Configure the project ``` idf.py menuconfig ``` Set following parameter under Serial Flasher Options: * Set `Default serial port`. Set following parameters under Example Configuration Options: * Set `IP version` of example to be IPV4 or IPV6. * Set `IPV4 Address` in case your chose IP version IPV4 above. * Set `IPV6 Address` in case your chose IP version IPV6 above. * Set `Port` number that represents remote port the example will connect to. Configure Wi-Fi or Ethernet under "Example Connection Configuration" menu. See "Establishing Wi-Fi or Ethernet Connection" section in [examples/protocols/README.md](../../README.md) for more details. ## Build and Flash Build the project and flash it to the board, then run monitor tool to view serial output: ``` idf.py -p PORT flash monitor ``` (To exit the serial monitor, type ``Ctrl-]``.) See the Getting Started Guide for full steps to configure and use ESP-IDF to build projects. ## Troubleshooting Start server first, to receive data sent from the client (application).