On Jan 3, 2006, at 5:46 PM, Warner Losh wrote:
As someone who has fought the battles, I can tell you that a simple table is 10x or 100x easier to implement than dealing with parsing the data from N streams. Sure, it limits the lifetime of the device, but a 20 year limit is very reasonable.
Simpler is indeed better - if it satisfies the requirements. While we're at it - how about a table to describe worldwide daylight saving rules? Oh right - we already have that :-) What we don't have is a mechanism to force the U.S. Congress not to change the rules out from under us. Retaining the flexibility to easily change the rules is one of our requirements. Twenty years does seem reasonable. Would suggest this might be marketed as an extended cadence maintenance requirement, rather than as an expiration date - suspect astronomers aren't the only ones to rely on 30 year old computers on occasion. I would heartily agree with the notion that a twenty year horizon is about appropriate for expecting to reach any decision on the future of UTC. We'd be a lot further ahead on this if a closed door decision hadn't been rushed for the imagined benefit of the few. In the mean time, there are many members of the astronomical software community who would be happy to contribute to an effort to improve time handling infrastructure and standards, rather than spending their own precious time fending off ill conceived political machinations.
If we could have a table for the next 20 years, there'd be no need to even write the code to get from the GPS stream :-)
And if latitude and longitude were engraved on every street corner, there would be no need for GPS at all :-) Transport of time signals to remote locations is the whole point.
I know you aren't pursuaded by such arguements.
I'm prepared to be persuaded by complete, coherent proposals based on real world (and real economic) concerns. But should any of us be open to persuasion by a "political tool to make the proposal go through without commiting anybody to anything for the next couple of hundred of years"?
I find your dismissive attitude towards software professionals that have implemented a complete leap second handling infrastructure, with pluggable sources for leap second rather annoying :-(
Indeed, I'm sure I've exhausted my scant store of good will again. It must be obvious that my intent was to come out swinging after the leap second - just as the obvious intent of the folks pushing the proposal is to use any reports of systems failing to appropriately handle the leap second as fodder for renewing their efforts. That said, if there are such reports, let's hear them and get to work together (for once). (Some might consider me a software professional as well - am not particularly annoyed if you do not.) Would be delighted to hear more about your leap second infrastructure. Rob Seaman National Optical Astronomy Observatory