int
__gen_tempname (char *tmpl, int kind)
{
  int len;
  char *XXXXXX;
  static uint64_t value;
  uint64_t random_time_bits;
  unsigned int count;
  int fd = -1;
  int save_errno = errno;
  struct_stat64 st;

  /* A lower bound on the number of temporary files to attempt to
     generate.  The maximum total number of temporary file names that
     can exist for a given template is 62**6.  It should never be
     necessary to try all these combinations.  Instead if a reasonable
     number of names is tried (we define reasonable as 62**3) fail to
     give the system administrator the chance to remove the problems.  */
#define ATTEMPTS_MIN (62 * 62 * 62)

  /* The number of times to attempt to generate a temporary file.  To
     conform to POSIX, this must be no smaller than TMP_MAX.  */
#if ATTEMPTS_MIN < TMP_MAX
  unsigned int attempts = TMP_MAX;
#else
  unsigned int attempts = ATTEMPTS_MIN;
#endif

  len = strlen (tmpl);
  if (len < 6 || strcmp (&tmpl[len - 6], "XXXXXX"))
    {
      __set_errno (EINVAL);
      return -1;
    }

  /* This is where the Xs start.  */
  XXXXXX = &tmpl[len - 6];

  /* Get some more or less random data.  */
#ifdef RANDOM_BITS
  RANDOM_BITS (random_time_bits);
#else
# if HAVE_GETTIMEOFDAY || _LIBC
  {
    struct timeval tv;
    __gettimeofday (&tv, NULL);
    random_time_bits = ((uint64_t) tv.tv_usec << 16) ^ tv.tv_sec;
  }
# else
  random_time_bits = time (NULL);
# endif
#endif
  value += random_time_bits ^ __getpid ();

  for (count = 0; count < attempts; value += 7777, ++count)
    {
      uint64_t v = value;

      /* Fill in the random bits.  */
      XXXXXX[0] = letters[v % 62];
      v /= 62;
      XXXXXX[1] = letters[v % 62];
      v /= 62;
      XXXXXX[2] = letters[v % 62];
      v /= 62;
      XXXXXX[3] = letters[v % 62];
      v /= 62;
 XXXXXX[4] = letters[v % 62];
      v /= 62;
      XXXXXX[5] = letters[v % 62];

      switch (kind)
        {
        case __GT_FILE:
          fd = __open (tmpl, O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR);
          break;

        case __GT_BIGFILE:
          fd = __open64 (tmpl, O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR);
          break;

        case __GT_DIR:
          fd = __mkdir (tmpl, S_IRUSR | S_IWUSR | S_IXUSR);
          break;

        case __GT_NOCREATE:
          /* This case is backward from the other three.  __gen_tempname
             succeeds if __xstat fails because the name does not exist.
             Note the continue to bypass the common logic at the bottom
             of the loop.  */
          if (__lxstat64 (_STAT_VER, tmpl, &st) < 0)
            {
              if (errno == ENOENT)
                {
                  __set_errno (save_errno);
                  return 0;
                }
              else
                /* Give up now. */
                return -1;
            }
          continue;

        default:
          assert (! "invalid KIND in __gen_tempname");
        }

      if (fd >= 0)
        {
          __set_errno (save_errno);
          return fd;
        }
      else if (errno != EEXIST)
        return -1;
    }

  /* We got out of the loop because we ran out of combinations to try.  */
  __set_errno (EEXIST);
  return -1;
}