dst?

/*
 *  call-seq:
 *     time.isdst => true or false
 *     time.dst?  => true or false
 *  
 *  Returns <code>true</code> if <i>time</i> occurs during Daylight
 *  Saving Time in its time zone.
 *     
 *     Time.local(2000, 7, 1).isdst   #=> true
 *     Time.local(2000, 1, 1).isdst   #=> false
 *     Time.local(2000, 7, 1).dst?    #=> true
 *     Time.local(2000, 1, 1).dst?    #=> false
 */

static VALUE
time_isdst(time)
    VALUE time;
{
    struct time_object *tobj;

    GetTimeval(time, tobj);
    if (tobj->tm_got == 0) {
        time_get_tm(time, tobj->gmt);
    }
    return tobj->tm.tm_isdst?Qtrue:Qfalse;
}