#include <stdio.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <fcntl.h>
#include <signal.h>

#define MAXFDS 32
int c = 0;

struct fd_info_t {
  int fd;
  void (*handler)(int);
} fd_info[MAXFDS];

int open_connection(char *address, int port) {
  int d;
  struct sockaddr_in sa;

  d = socket(AF_INET, SOCK_STREAM, 0);

  sa.sin_family = AF_INET;
  sa.sin_port = htons(port);
  inet_aton(address, &sa.sin_addr);

  return (connect(d, (const struct sockaddr *)&sa, sizeof(sa)) == 0) ? d : -1;
}

void add_handler(int fd, void (*h_f)(int)) {
  if (c != MAXFDS && fd != -1) {
    fcntl(fd, F_SETFL, O_ASYNC);
    fcntl(fd, F_SETOWN, getpid());

    fd_info[c].fd = fd;
    fd_info[c].handler = h_f;

    c++;
  }
}

void manage(int n) {
  int i, l;
  fd_set readfds;

  FD_ZERO(&readfds);
  for (i=0,l=0; i<c; i++,l=(fd_info[i].fd > l) ? fd_info[i].fd : l)
    FD_SET(fd_info[i].fd, &readfds);

  select(l+1, &readfds, 0, 0, 0);

  for (i=0; i<c; i++)
    if (FD_ISSET(fd_info[i].fd, &readfds)) {
      fd_info[i].handler(fd_info[i].fd);
      break;
    }
}

void read_data(int fd) {
  char buffer[1024];

  memset(buffer, 0, 1024);
  read(fd, buffer, 1024);
  write(1, buffer, 1024);
}

int main(void) {
  signal(SIGIO, manage);

  add_handler(0, read_data);
  add_handler(open_connection("127.0.0.1", 31331), read_data);
  add_handler(open_connection("127.0.0.1", 31332), read_data);

  while(1) sleep(1); /* begin madness */

  return 0;
}