[tz] leapseconds.awk, LEAP directives and references

[Paul Eggert]

John Hawkinson wrote:

> (1) A work may be in the public domain without an explicit declaration
> if the author has made it sufficiently clear in other places....
>
> (2) Just because a file is copyrighted does not mean it cannot be
> reproduced without permission. In the US we have "fair use,"...
>
> Additionally, *facts* cannot be copyrighted.

All quite true. Alas, none of these escape hatches would save us if we copied 
the entire IERS file, as (a) copying the whole thing clearly would not be fair 
use, (b) the file has not been placed in the public domain (and I doubt whether 
it can be, as its authors are under French law), and (c) the file clearly 
contains expression as well as simple records of facts.