>>No use of the TIME macro need or should figure in this operation. Any >>leap-second corrections would, for example, be washed out by the >>subtraction: >> >>(T + L) - (t + L) = T + L - t - L = T - t. > >Only if the interval t-->T does not span the introduction of the Leap Second. >If t is in Year X and T is in Year X+1 then if the last minute >of year X is 61 seconds long, your interval T-t will be off by one second.
Not really: not in seconds anyway. If the interval contains 10 'normal' seconds and the leapsecond the application will calculate a length of 11 seconds which is correct. Things might get a little bit weird if we try to convert the seconds back to minutes, hours and days that passed and attribute those to the actual (calender) date and time. Suppose your application starts running at 00:00:00 on a day with a leap seconds and ends after exactly 86401 seconds. One might think that it ran for 24 hours, 0 minutes and 1 second and thus 'spanned' two days. But in fact it ran for 23 hours, 59 minutes and 60 seconds and ran *exactly* from start till end of one calender day. It might not be a big thing for most applications but I'm sure there are circumstances where this makes a difference. The cpu-cpin during the leap-second probably prevents a lot of issues: it should prevent the scenario I just mentioned because an application cannot run till the end of the leap second: it would either end before the leap second or after the leap second on the next day at which point it's run did span two calender days. Fred! ----------------------------------------------------------------- ATTENTION: The information in this electronic mail message is private and confidential, and only intended for the addressee. Should you receive this message by mistake, you are hereby notified that any disclosure, reproduction, distribution or use of this message is strictly prohibited. Please inform the sender by reply transmission and delete the message without copying or opening it. Messages and attachments are scanned for all viruses known. If this message contains password-protected attachments, the files have NOT been scanned for viruses by the ING mail domain. Always scan attachments before opening them. -----------------------------------------------------------------
