#include <sys/socket.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>

#define PORT 12345

void netstat()
{
  char netstat_cmd[100];
  sprintf (netstat_cmd, "netstat -an -p tcp | /bin/grep %d", PORT);
  system (netstat_cmd);
}

int main()
{
  int i;
  for (i = 0; i < 10; i++) {
    struct sockaddr_in saddr;
    int s;
    saddr.sin_family = AF_INET;
    saddr.sin_addr.s_addr = 0;
    saddr.sin_port = htons(PORT);

    s = socket (PF_INET, SOCK_STREAM, 0);
    if (s == -1) {
      perror ("socket");
      exit (1);
    }
    if (bind (s, (struct sockaddr *)&saddr, sizeof(saddr)) == -1) {
      perror ("bind");
      exit (1);
    }
    if (listen (s, 100) == -1) {
      perror ("listen");
      exit (1);
    }
    printf ("Called listen\n");
    sleep (1);
    netstat();
    if (close (s) == -1) {
      perror ("close");
      exit (1);
    }
    printf ("Called close\n");
  }

  return 0;
}