Reactive Programming with RxJava

Appendix A. More HTTP Server Examples

This appendix expands the contents of “Beating the C10k Problem” by providing more examples of HTTP servers. These examples are not essential to understand Chapter 5, but you might find them interesting. Also, some of these examples are included in the benchmarks.

fork() Procedure in C Language

We will try to implement a concurrent HTTP server using C. If you are familiar with C, you will find the following program fairly straightforward. Otherwise, do not worry, you are not obligated to understand all of the details, just the overall idea. Invoking fork() makes a copy of the current process, so that suddenly two processes appear in the operating system: the original one (parent) and a child. This second process has the exact same variables and state, the only difference is the result value of fork():

#include <signal.h>
#include <stdlib.h>
#include <string.h>
#include <netinet/in.h>
#include <unistd.h>
#include <stdio.h>

int main(int argc, char *argv[]) {
  signal(SIGCHLD, SIG_IGN);
  struct sockaddr_in serv_addr;
  bzero((char *) &serv_addr, sizeof(serv_addr));
  serv_addr.sin_family = AF_INET;
  serv_addr.sin_addr.s_addr = INADDR_ANY;
  serv_addr.sin_port = htons(8080);
  int server_socket = socket(AF_INET, SOCK_STREAM, 0);
  if(server_socket < 0) {
    perror("socket");
    exit(1);
  }
  if(bind(server_socket,
        (struct sockaddr *) &serv_addr,
        sizeof(serv_addr)) < 0) {
    perror("bind");
    exit(1);
  }
  listen(server_socket, 100);
  struct sockaddr_in cli_addr;
  socklen_t