time.c:1077
static VALUE
time_year(time)
    VALUE time;
{
    struct time_object *tobj;

    GetTimeval(time, tobj);
    if (tobj->tm_got == 0) {
	time_get_tm(time, tobj->gmt);
    }
    return LONG2NUM((long)tobj->tm.tm_year+1900);
}
