[tz] New leapseconds.awk doesn't work on macOS

[Guy Harris]

On Jan 10, 2020, at 10:26 PM, enh via tz <tz at iana.org> wrote:

> NetBSD already supported regular expressions in RS, and they
> upstreamed that to one-true-awk last year

macOS:

	https://opensource.apple.com/source/awk/awk-24/

uses what I'm guessing, based on the Lucent copyrights, is the One True Awk:

	https://github.com/onetrueawk/awk

and I suspect most if not all of the *BSDs do so as well, but macOS seems to be using a 2007-vintage version.  Perhaps they should update, especially to a version that has...

> (https://github.com/onetrueawk/awk/commit/643a5a3dad633431c6ce8831944c23059a6be309
> and https://github.com/onetrueawk/awk/commit/7cae39dfa53e17981990f649a2f6b4c1ba856112)
> so hopefully all the OSes not using gawk can unify at some point.

...that change.

> but, yeah, right now most awks don't have this ability.

...so the tzcode should probably not depend on it.