For this http server, main loop looks something like:

// set up listen socket
int listenSocket = ...

// Install signal handler(s) to clear the running flag

struct pollfd *pollData = ... // add listenSocket to poll 

while (running) {
  int pollResult = poll(...)

  switch (pollResult) {
    case -1:
       // Handle poll error, probably by falling out the loop
    case 0:
      // Poll timeout, continue the loop
      // (going this to give signals a chance to gracefully shut down)
      continue;
  }
  
  // this is where i got bored/ran out of energy
}

// Tidy up

// close listen socket
// close client sockets