[LEAPSECS] LEAPSECS Digest, Vol 82, Issue 6
joegwinn at comcast.net
Sun Aug 11 14:40:37 EDT 2013
On Sun, 11 Aug 2013 14:21:41 -0400, Greg Hennessy wrote:
>> The POSIX standard in fact forbids it, precisely to escape the time
> If the guys writing POSIX think that forbidding POSIX from matching
> reality means no time wars, I think they have another think coming.
No, we already had the time war. Twice. It's a very long story,
documented in the TimeNuts archive, which in turn points to the noisy
debates in the POSIX world.
>> However, POSIX allows an implementation (read, operating system) to
>> define as many named clocks as desired.
> I have never head of this before. How does one define a (for example)
> UTC clock in a POSIX system?
As a user, you do not. As a platform developer such as Linux kernel
developer, you can.
Here is some debate about two named clocks in POSIX/Linux:
The general interface used by these two named clocks can be extended by
a kernel developer.
At this point, people usually ask why this could not also be provided
to the user. The problem is that one cannot just whistle a new kind of
clock up. The hardware and kernel must support it, and these things
cannot be provided by a user.
More information about the LEAPSECS