Re: PATCH: eliminate backtick substitution

[Dmitry V. Levin]

Hi Karl,

On Tue, Dec 01, 2020 at 04:40:07PM -0700, Karl Berry wrote:
> Hi Dmitry,
> 
>     It's time to join the 1990s and replace the backtick substitutions in
>     config.guess and config.sub with the $(..) command substitution
> 
> I admit I don't understand the reason behind this last change that Ben did.
> What's wrong with `...`?
> 
> No question $(...) is nicer in principle, but the $(...) requirement
> breaks Solaris 10 (per the last autoconf pre-release
> announcement,
> https://lists.gnu.org/archive/html/autotools-announce/2020-12/msg00000.html).

Does it really break Solaris 10?  The announcement says that
"Configure scripts will automatically locate a shell that supports
this feature and re-execute themselves with it, if necessary,
so the new requirement should be transparent to most users."

I suppose the change is not expected to cause any problems for users
because they are highly likely to have some POSIX shell installed.

> If there is an actual technical advantage to using $(...), that's one
> thing, but if it's merely to use a prettier feature, then I don't see
> why that's a good enough reason to break longstanding compatibility.

There is a BashFAQ entry why $(...) is preferred over `...`:
https://mywiki.wooledge.org/BashFAQ/082


-- 
ldv