04_intro_to_sockets: update readme

04_intro_to_sockets/README.md

@@ -1,20 +1,45 @@
-# IO Access
+#  Daytime TCP Server and Client
 
-This program demonstrates how to access the GPIO pins on the Raspberry Pi using
-a LED, a button and a temperature sensor.
+## Description
+
+This project implements a daytime TCP/UDP server and client. 
+The server listens for incoming connections and responds with the current date
+and time. The client sends a message to the choosing the output format of the
+date and time. The server responnds with 
 
 ## Usage
 
 ```bash
 $ make
+# start tcp server
+$ bin/daytimeTCPSrv <port>
+# run tcp client
+$ bin/daytimeTCPCli <server-ip> <server-port> <message>
+
+# start udp server
+$ bin/daytimeUDPSrv <port>
+# run udp client
+$ bin/daytimeUDPCli <server-ip> <server-port> <message> 
 ```
 
 ## Testing with nc
 
-Clients:
+Start nc as a server. It will display any data it receives. The user can make
+nc reply to the client by typing in the terminal.
+
 ```bash
 # TCP
 $ nc -l 1234
 # UDP
 $ nc -ul 1234
 ```
+
+Start nc as a client. It will send any data it receives from the user to the
+server.
+
+```bash
+# TCP
+$ nc <server-ip> <server-port>
+# UDP
+$ nc -u <server-ip> <server-port>
+```