Re: config.sub/config.guess using nonportable $(...) substitutions

[Todd C. Miller]

On Tue, 09 Mar 2021 14:11:36 -0700, Warren Young wrote:

> That’s the real trick, isn’t it?  We have to set *some* threshold for droppin
> g support for old platforms.  I expect Autoconf isn’t compatible with Ultrix 
> any more, for instance.

That's a good reminder that we've been here before.  I remember
being somewhat irked when autoconf stopped working with the SunOS
4.x /bin/sh (due to the use of shell functions IIRC).  When I found
that bash would process the script far faster than the V7-derived
shell could I didn't mind any more :-)

And as Paul pointed out earlier, Solaris 10 has multiple shells
that support $( cmd ) syntax, they just aren't called /bin/sh.

 - todd