if (fd == -1
if (__builtin_expect (fd, 0) == -1
is_smp_system (void){  static const int sysctl_args[] = { CTL_KERN, KERN_VERSION };  char buf[512];  size_t reslen = sizeof (buf);  /* Try reading the number using `sysctl' first.  */  if (__sysctl ((int *) sysctl_args,		sizeof (sysctl_args) / sizeof (sysctl_args[0]),		buf, &reslen, NULL, 0) < 0)    {      /*This was not successful.  Now try reading the /proc filesystem.  */      int fd = __open ("/proc/sys/kernel/version", O_RDONLY);      if (fd == -1	  || (reslen = __read (fd, buf, sizeof (buf))) <= 0)	/* This also didn't work.  We give up and say it's a UP machine.  */	buf[0] = '\0';      __close (fd);    }  return strstr (buf, "SMP") != NULL;}