On Mon Aug 19 15:37:24 EDT 2013, cinap_len...@gmx.de wrote:
> x=foo; @{x=bar}; echo `{cat /env/x}
>
> yields "foo" but
>
> x=foo; echo; @{x=bar}; echo `{cat /env/x}
>
> yields "bar"
>
> the problem is that the environment variables are
> only flushed to /env on exec, but not on fork.
>
> in the first example, after executing the
> subshell, x is still marked as "modified" by
> us and the cat/echo will cause the old value
> to be flushed and the changed value from the
> subshell be overridden.
>
> havntfork.c does flush the variables on fork tho.
>
> i think it would be more consistent todo this for
> havefork.c as well.
>
> is there a good reason not to?
here are three reasons. i am not sure if any of them are
good
- it is going to be nearly impossible to
tell if this behavior is depended on somewhere.
- it also potentially has performance implications.
- subshells can also run asynchronous, asynchronously
modifying the environment. don't we still have a race?
- erik
