Update README.md

README.md

 # udp sockets testing
 
+## comments
+* server port is hardcoded
+
+## build
+```sh
+gcc receiver.c -o receiver; gcc sender.c -o sender
+```
+
+## run
+
+### receiver (server)
+
+PC1, console 1:
+```sh
+./receiver
+```
+
+### sender (client)
+
+PC1, console 2:
+```sh
+./sender
+```
+or
+
+PC2, console 1:
+```sh
+./sender <PC1-IPADDR>
+```
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