[tz] New Yorker article on David Mills and NTP

[Brian Inglis]

On 2022-10-06 19:34, Paul Eggert via tz wrote:
> On 10/6/22 15:45, Garrett Wollman via tz wrote:
>> C (intentionally) does not make any requirements on the encoding of a
>> time_t, other than requiring that it be numeric.  tzcode contains lots
>> of complexity to deal with the numerous possible different
>> realizations allowed by the C standard.

> Despite its complexity, tzcode no longer supports every possibility 
> allowed by the C standard. I removed support for floating-point time_t 
> in 2013e, with the comment "It wasn't tested and probably never worked, 
> no platform used it, and the latest POSIX no longer allows it."

AFAIR only C libraries for IBM 360/370/390/z e.g. IBM OS/MVS and VM/CMS 
SAS/C, used double time_t to handle the IBM ToD clock (later SysPlex 
timer IIRC) specified in the arch to update bit 52 (BE) every µs, but 
provided total 64(/128) bits with as much precision as required for 
discrete timestamps for hardware error logs. Looks like SAS/C support 
stopped in 2001.
[Gig was porting a Windows 16 bit product to work across IBM OSes!]

-- 
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

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[Data in binary units and prefixes, physical quantities in SI.]