[HECnet] How long has your 20 been up?

Cool thread, reminds of many leap year issues we fixed in All-In-One a long, long time ago. I think at the year 33000 there will be other issues to tend with than RSX or other Digital Equipment software going bonkers ? Unless of course the Metaverse runs on RSX then of course all bets are off ? Mike Sent from Mail <https://go.microsoft.com/fwlink/?LinkId=550986> for Windows *From: *Paul Koning <mailto:paulkoning at comcast.net> *Sent: *Tuesday, January 18, 2022 11:43 AM *To: *hecnet at update.uu.se <mailto:hecnet at update.uu.se> *Subject: *Re: [HECnet] How long has your 20 been up? don't remember what that limit is.? What are the limits for other systems? planned shutdowns (say, for preventive maintenance) were a regular occurrence) would overlook silly bugs like that.? It feels like the sort of thing that minicomputer software, especially real time systems, would never do.? For example, RSTS has no uptime limit. Or rather a time problem. Because of the way time is represented, everything will fail catastrophically somewhere around the year 31000. VMS represents time as a signed quad. 100ns resolution, and offset from 1858 (or whenever it was). Anyway, the important bit is that it is signed, and it has to be positive. times. And so, when the time actually wraps over, things will go totally bonkers in VMS. before then, like when years start needing 5 digits... Time representation might get a bit broken around the year 33000 or so, but I don't think anything catastrophic will break. Years are just a 16 bit value with an offset of 1900. But very few things even use it for anything, except printing it out. So signedness or not might cause things to look funny depending on the code, but most software itself will not care. time stamps on files will wrap, queue manager time handling will break/wrap, and of course DECnet time representation can't deal with it. But the OS itself will probably just continue chugging along, as will most software. Time stamps are interesting.? DECnet event timestamps ran out of bits recently, unless you ignore the spec's statement that the 16-bit field is signed.? If treated as unsigned you've got until 2038 or so. RSTS timestamps overflow in 2035.? RT-11 ran into trouble before Y2K though I think there are workarounds for that -- which are not implemented everywhere.? DOS-11 format DECtape ran into trouble in April of 1974 (12 bit timestamps), I remember creating a RSTS patch for that in college and sending it to DEC.? :-) ??????????????? paul