bug#71655: Eshell external commands do not work under GNU Emacs for Windows

[Michael Albinus via "Bug reports for GNU Emacs, the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>]

Jim Porter <jporterbugs@gmail.com> writes:

Hi Jim,

> That could work, though thinking about this some more, I think there's
> a benefit to being careful about how we add checks here. For Tramp
> files, we should probably try to keep the number of calls that need to
> touch the remote filesystem to a minimum.
>
> I'll think about this some more and see if we can get all the checks
> we want without making the code slower over Tramp. (Maybe Tramp caches
> enough that this isn't a problem, but I'm not certain yet.)

If Eshell calls `process-file', it shall bind `process-file-side-effects'
to nil if appropriate for the given command.

Furthermore, Eshell might bind `remote-file-name-inhibit-cache' to
something which helps. The default value (10) seems to be very conservative.

In case Eshell needs to clear the cache for a given directory, there is
`dired-uncache'. Contrary to its name, it is not restricted to dired,
but of general purpose.

Best regards, Michael.