#include <sys/types.h>
#include <sys/stat.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <time.h>
#include <pthread.h>

#define NTHREADS 300

void *thread_function();
int open_fail_num;
int open_success;

int
main(int argc, char *argv[])
{
  int i, j;
  pthread_t thread_id[NTHREADS];

  for(;;)
    {
      for(i=0; i < NTHREADS; i++)
	{
	  pthread_create(&thread_id[i], NULL, &thread_function, NULL);
	}
      for(j=0; j < NTHREADS; j++)
	{
	  pthread_join(thread_id[j], NULL); 
	}
      printf("open failures: %i\n", open_fail_num);
      printf("open success: %i\n", open_success);
    }
}

void *thread_function()
{
  int fd;
  time_t t;

  //  fd = open("/dev/cua0", O_NONBLOCK);
  //  fd = open("/dev/cua0", O_RDWR);
  fd = open("/dev/tty9", O_RDWR);

  //  if (fd == -1)
  if (fd < 0)
    {
      open_fail_num++;
      //      perror("open");
      //      exit(1);
    }
  else
    {
      open_success++;
    }
  /* just waste some random time */
  t = (time((time_t *)0) &31L) << 6;
  while (t-- > 0)
    (void)time((time_t *)0);
  close(fd);	
  //  _exit(0);
}