🚀 go-pugleaf

Maybe this is a generic Unix programming question, but...
Is there any way to find out whether or not your localtime is in 
daylight savings time (DST) or not?  I have a time function that works
when I'm using a non-DST (e.g. GMT-0800), however when I change my 
time zone to DST (e.g. PST), it breaks.  If only I could tell.  I 
thought the following would work:

timePtr = localtime(&clock);
isDST = timePtr->tm_isdst;

but isDST is *always* 0, no matter where I set the clock.  Any ideas?

Thanks, ...Michael Brill