42 Exam 06 Review

The environment for Exam 06 is intentionally stripped down to test your raw coding ability.

The assignment requires managing multiple client connections simultaneously using non-blocking I/O or multiplexing.

You should be able to write the socket initialization and select() loop blindly. Practice this until it becomes muscle memory. 42 Exam 06

select() blocks until activity occurs on any registered file descriptor. Step 3: Handling New Connections

to take the new client. Assign them a unique ID and send a "server: client [ID] just arrived" message to everyone else. Handling Client Messages : If a client socket is "ready," read the data. Disconnection The environment for Exam 06 is intentionally stripped

+---------------------------------------------+ | Initialize Server | | socket() -> setsockopt() -> bind() -> listen() | +---------------------------------------------+ | v +---> +---------------------------------------------+ | | Copy Master Sets to Active | | | (Read & Write fd_sets for select) | | +---------------------------------------------+ | | | v | +---------------------------------------------+ | | select() | | | (Blocks until I/O is ready) | | +---------------------------------------------+ | | | v | +---------------------------------------------+ | | Loop through all active FDs | | +---------------------------------------------+ | / \ | v v | [ If FD == Server ] [ If FD == Client ] | | | | v v | +---------------+ +---------------+ | | accept() | | recv() Data | | | Add Client | +---------------+ | +---------------+ / \ | v v | [ Bytes > 0 ] [ Bytes <= 0 ] | | | | v v | +---------------+ +---------------+ | | Buffer String | | Close Socket | | | Parse Newlines| | Remove Client | | | Broadcast | | Broadcast | | +---------------+ +---------------+ | | | +--------------------------------------|---------------+ v Phase 1: Global and Structural Setup

The rank exams from 02 to 06 form a step-by-step path through the Common Core curriculum, each one building upon the knowledge from the previous. Practice this until it becomes muscle memory

While earlier exams focused on the fundamentals of C and system calls, Exam 06 pivots toward the complexities of and concurrency . Here is a comprehensive look at what the exam entails and how to prepare for it. What is Exam 06?

If activity is on the server socket, accept() the new connection.