Re: Non file buffers and default-directory

[Eli Zaretskii <eliz@gnu.org>]

> From: Tim Landscheidt <tim@tim-landscheidt.de>
> Date: Thu, 27 Apr 2023 12:04:48 +0000
> 
> Side note: I would love a well-maintained example of an
> "asynchronous" user interface in Emacs.
> 
> I have a bunch of shell/Perl/Python scripts that I'd like to
> convert to Emacs Lisp for a consistent UI that can also be
> used over SSH.
> 
> For example, I have a script that plays a podcast's audio
> file and afterwards asks me if the associated database entry
> selected from a list of suggestions should be marked as
> heard (and the file archived).  I also use this as part of
> sequences, i. e. "$script file1.mp3 && $script file2.mp3".
> 
> Now in Emacs, I obviously would want to continue to work on
> something else while the audio is playing in the background.
> I also don't want that other work to be interrupted in the
> sense of a blocking minibuffer prompt when the playback has
> finished.  And I also don't want to accidentally quit Emacs
> without me being reminded, "hey, that playback has finished,
> should it be marked as heard?"  And I want that "bit" to be
> usable as part of a sequence, i. e. after answering the
> question, the next statement should be executed.

AFAIU, this has nothing to do with Lisp threads.  Every modern OS is
capable of playing audio/video clips in the background, so all you
need is invoke your player (or the script which invokes the player) in
that background mode.