Re: exec-path and PATH

[Christoph Scholtes <cschol2112@googlemail.com>]

Eli Zaretskii <eliz@gnu.org> writes:

>> Can we set PATH to exec-path for the duration of the shell
>> execution?
>
> What do you mean by "shell execution"?

While the shell is executing the external program.

> What I had in mind was that we should synchronize PATH with exec-path
> each time we invoke a subsidiary process, either through call-process
> or start-process.

That should work, but I wonder if we want to do this work before every
process. It would be nicer to sync the two whenever exec-path is
modified. I don't know if this is possible though when modifying
exec-path diretcly via setq, for example.

Maybe that's premature optimization tough.

> There could be an issue with async subprocesses that are already
> running, though: they still use the old PATH, while Emacs will see the
> new value.  This could lead to subtle bugs.

This would only be a problem if the exec-path was modified between two
processes. Also, this problem exists today, if I modify the PATH in
between two processes via setenv, right?

>> IIRC, if you change the PATH in a cmd session it only applies to
>> that session.
>
> But we don't change PATH _in_ the cmd session, we change it _before_
> the session begins.

I can change the PATH after running an instance of cmd.exe, no? It will
change the PATH for that session only, iirc.

Christoph