[ACCEPTED]-Accept multiple subsequent connections to socket-sockets

Accepted answer
Score: 11

Yes, you can accept() many times on the listening 10 socket. To service multiple clients, you 9 need to avoid blocking I/O -- i.e., you 8 can't just read from the socket and block 7 until data comes in. There are two approaches: you 6 can service each client in its own thread 5 (or its own process, by using fork() on UNIX systems), or 4 you can use select(). The select() function is a way of 3 checking whether data is available on any 2 of a group of file descriptors. It's available 1 on both UNIX and Windows.

Score: 7

Here is a simple example from Beej's Guide to Network Programming.

while(1) {  // main accept() loop
    sin_size = sizeof their_addr;
    new_fd = accept(sockfd, (struct sockaddr *)&their_addr, &sin_size);
    if (new_fd == -1) {

        get_in_addr((struct sockaddr *)&their_addr),
        s, sizeof s);
    printf("server: got connection from %s\n", s);

    if (!fork()) { // this is the child process
        close(sockfd); // child doesn't need the listener
        if (send(new_fd, "Hello, world!", 13, 0) == -1)
    close(new_fd);  // parent doesn't need this

The child 3 process — after the fork() — handles the communication 2 asynchronously from accept()ing further connections 1 in the parent.

Score: 0

Yes, you have the right general idea.

While 10 my C socket programming is a bit rusty, calling 9 accept on a server socket sets up the communications 8 channel back to the client side of the socket. Calling 7 accept on future connection attempts will 6 set up multiple socket channels.

This means 5 that one should take care to not overwrite 4 a single shared structure with a specific 3 connection's data, but it doesn't sound 2 like that's the kind of error you would 1 be prone to make.

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