Nicely avoiding DST problems and leaving them to the customer. The leapsecond is added after 23:59:59, so before midnight. No confusion there.
Kees. -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of Paul Gilmartin Sent: Friday, June 07, 2013 16:05 To: [email protected] Subject: Re: Age of datasets in hours, not days? On Thu, 6 Jun 2013 23:48:46 -0700, Ed Jaffe wrote: > >DS9TIME DS XL6 Number of microseconds since >* midnight, local time, ... > Did I fail to read this correctly previously? Now that I look more carefully, it seems to be saying that the field stores a counter that is reset to 0 each midnight, local time, and counts uniformly until the next midnight. So on most days, it will reset after 24 hours worth of microseconds. On the day of the Fall Daylight Saving Time boundary, it will reset only after 25 hours' worth of microseconds; on the day of the Spring Daylight Saving Time boundary, it will reset after only 23 hours' worth of microseconds. No ambiguity, but tricky to convert to local time. And the best way for allocation to compute the needed value is to save the (E)TOD value each midnight and subtract from the (E)TOD value at the time of allocation. Are there locales where the Daylight Saving Time boundary occurs at midnight, or spans midnight so there might be two midnights, an hour apart? Or none, in the Spring? Leap seconds? If one is concerned with microsecond precision, one needs to be concerned with how leap seconds are treated. -- gil ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN ******************************************************** For information, services and offers, please visit our web site: http://www.klm.com. This e-mail and any attachment may contain confidential and privileged material intended for the addressee only. If you are not the addressee, you are notified that no part of the e-mail or any attachment may be disclosed, copied or distributed, and that any other action related to this e-mail or attachment is strictly prohibited, and may be unlawful. If you have received this e-mail by error, please notify the sender immediately by return e-mail, and delete this message. Koninklijke Luchtvaart Maatschappij NV (KLM), its subsidiaries and/or its employees shall not be liable for the incorrect or incomplete transmission of this e-mail or any attachments, nor responsible for any delay in receipt. Koninklijke Luchtvaart Maatschappij N.V. (also known as KLM Royal Dutch Airlines) is registered in Amstelveen, The Netherlands, with registered number 33014286 ******************************************************** ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
