>And IBM provides no way to do that correctly. Care to elaborate?
The documented process when leap seconds are specified is to schedule the leap second change via the STP panels to occur at the published time. That way the z/OS UTC time remains accurate. When the +1 leap second update is processed we spin for 1 second to ensure there are no duplicate UTC time stamps. That seems pretty correct to me. If you're referring to formatting the date/time from a time stamp and not taking into account just when a leap second (or a daylight savings time) change occurred, I agree that that is what happens (and in practice I suspect you'd be unlikely to be able to make a business case that doing so is either needed or would be worth the increased path length). Peter Relson z/OS Core Technology Design
