CASE STUDY // SYSTEMS

ft_irc

RFC 2812 Compliant IRC Server in C++

A fully functional IRC (Internet Relay Chat) server built in C++98, compliant with RFC 2812 standards. Supports real-time authentication, multi-channel messaging, operator privileges, and bot interactions.

LIVE ARCHITECTURE SIMULATORInteractive Demo

ft_irc Async Socket Multiplexer (`poll()`)

RFC 2812 compliant non-blocking I/O event loop and client state machine.

Event Loop StateWAITING

Syscall:poll(fds, 3, -1)

Non-blocking Mode:O_NONBLOCK (fcntl)

Max Connections:1024 Socket FDs

Active Socket File DescriptorsRFC 2812 State Matrix

fd 4aymane(HexChat)

#1337NICK aymane

fd 5guest_99(Irssi)

#generalJOIN #42

fd 6bot_assistant(IRC Bot)

#1337PRIVMSG #1337 :Hello!

Live Network Log StreamIRC Protocol Output

4:30:36 PM [SYS] poll() monitoring 3 socket file descriptors...

4:30:36 PM [NET] Connection established on socket fd 5 (IP: 127.0.0.1)

4:30:36 PM [IRC] Client 'aymane' joined channel #1337

Accessible Socket Multiplexer Log (Screen Reader Data)

The ft_irc server uses poll() to monitor multiple client socket file descriptors asynchronously. Client socket 4 (aymane), socket 5 (guest_99), and socket 6 (bot_assistant) are handled on a single thread without blocking.

Initializing ft_irc Socket Multiplexer...

Protocol

RFC 2812

Concurrency Model

Non-blocking poll()

Clients Tested

HexChat & Irssi

The Challenge

Managing dozens of concurrent socket connections non-blockingly without thread overhead or socket blocking hangs.

Architectural Approach

Architected an event-driven network engine using poll() / kqueue I/O multiplexing, non-blocking sockets, and a state machine command parser.

Engineering Impact

Highlights deep expertise in TCP/IP networking, socket programming, async I/O multiplexing, and protocol specification compliance.

Technical Key Highlights

▸Non-blocking I/O multiplexing with poll() system call
▸Channel management (operators, invites, topic control, modes)
▸Tested against official IRC clients (HexChat, irssi)
▸Integrated automated IRC assistant bot

Technologies Used:C++98TCP/IP Socketspoll() Async I/OIRC RFC 2812Network Protocol