static VALUE last_pid(VALUE obj) {
	FILE *f = fopen("/proc/loadavg", "r");
	if (!f) return Qnil;

	unsigned long long _last_pid;
	char status = fscanf(f, "%*f %*f %*f %*s %llu", &_last_pid);
	fclose(f);
	if (status != 1) return Qnil;

	return ULL2NUM(_last_pid);
}
