[LEAPSECS] operational time -- What's in a name?

[M. Warner Losh]

In message: <4353.1206704545 at critter.freebsd.dk>
            "Poul-Henning Kamp" <phk at phk.freebsd.dk> writes:

: In message <20080328041505.GA20152 at ucolick.org>, Steve Allen writes:

: 

: >> In 1961, the task was on a few handfulls of scientific people, most,

: >> if not all, of them phd's, and all of them very much at home in the

: >> subject domain.

: >>

: >> Fiddling with time_t today would involves more than a million

: >> persons, very few of which can readily tell you what a leap-second is.

: >

: >I disagree.  All of the technical part falls into the hands of the

: >folks who maintain the zoneinfo files and their code equivalents

: >(including other, non-POSIX systems for timezone offsets).

: 

: No, that is only the part where time_t gets converted to local time.

: 

: All the code that assume that time_t is UTC will get burned, and

: trust me: that is far more code than you imagine.n 

: 

: >The rest of those million people need merely install a zoneinfo and

: >code update as they do every time any jurisdiction decides to change

: >the dates of its daylight time transition.

: 

: Simply not true.  A good place to start is the FreeBSD ports-tree

: which contains about 18000 piece of open source software.

: 

: Try to change time_t to a non-arithmetic type and see how far you

: get.


although naive math is, well, naive, more code exists that assumes,
for example, that midnight it time_t % 86400 == 0 than you want to
believe.  Changing this is really bad karma.


: >That POSIX time_t henceforth be interpreted as TI, and that the leap

: >seconds go into the zoneinfo files such that most time zones,

: >including UTC, start being a number of hours minus leap seconds off

: >from TI.

: 

: This is exactly the flagday that will make the upgrades to a few

: hundered telescopes look like peanuts.


Fuck the telescopes software.  it is order of magnitudes less common
than anything else as to be irrelevant than things like ntp.

Leap seconds are evil and must die.  Society can with stand almost two
hour of deviation from solar time.  Why does even a leam minute mean
anything to 99% of the population.

Warner