Hi all, I am adding time zone support to our multi-platform application and there are still a few things I cannot figure out. 1) What is the difference between America/Detroit and posix/America/Detroit? The test cases I have written return what looks like the same DST record for a given date no matter which one I use. Under what circumstances would I use posix/America/Detroit? 2) Where is the format of the tz source filesdescribed? Specifically what do SAVE and Letter/S mean below? I am also interested in what the Link format is. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Nic 1979 1980 - Mar Sun>=16 0:00 1:00 D Rule Nic 1979 1980 - Jun Mon>=23 0:00 0 S 3) AIX machines use their own wacky format such at TZ=EST5EDT. Is there any decent mapping to real names? I have googled my brains out on this and searched the comp.time.tz archives on gmane with no luck. Thanks in advance, Donald