Re: variable set in exec'ing shell cannot be unset by child shell

[Greg Wooledge]

On Fri, Oct 13, 2023 at 02:21:59PM -0400, Dale R. Worley wrote:
> I was too lazy to chew through your example, but I coded an instance of
> your description (above), and it does not show the dubious behavior that
> you report.  Specifically,
> 
>     $ bash -version
>     GNU bash, version 5.1.0(1)-release (x86_64-redhat-linux-gnu)
>     ...
>     $ ls -l
>     total 20
>     -rwxr-xr-x. 1 worley worley 112 Oct 13 14:14 inner
>     -rw-r--r--. 1 worley worley 113 Oct 13 14:13 middle
>     -rw-r--r--. 1 worley worley 123 Oct 13 14:12 outer

>     $ cat inner
>     echo "Value in ./inner at the beginning: $OUTSIDE"
> 
>     unset OUTSIDE
> 
>     echo "Value in ./inner at the end: $OUTSIDE"

I tried to understand the question as well.  I got as far as realizing
there were *three* scripts, not two as originally stated (your example
agrees).  But the OP's third script wraps around and re-invokes the
first one.  It's an ouroboros snake.

Your example doesn't circle around in the same way, so I don't know how
faithfully it's reproducing the original question.

Once I realized there was an infinite loop of scripts eating their own
tails, I gave up trying to understand any further.  Too complicated for
me.