Chat software for UNIX OS / for JPN / as school exercises
Works in a LAN.

UNIX variants
Tested on Debian, macOS Sierra, Vine Linux.
server2 was tested on only macOS Sierra.

Just compile.
gcc -o server server.c or gcc -o server server2.c
gcc -o client client.c

1. Check the IP address of your server machine.
2. Start server on a server machine.
3. Start client on client machines.
4. Enter the IP address of the server.
5. Enter your name.
6. You can start chat.

You can use following commands.
NAME@your-name : Change your name.
RE@destination (name)@message : Reply message (Other clients can't see this message.)
LIST : Show online users (only server2)
LOGOUT : Logout
END : Terminate all clients and server.