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From: Stefan Monnier via Users list for the GNU Emacs text editor <help-gnu-emacs@gnu.org>
To: help-gnu-emacs@gnu.org
Subject: Re: unwind-protect and inhibit-quit
Date: Fri, 16 Jul 2021 11:00:14 -0400	[thread overview]
Message-ID: <jwv4kcul35y.fsf-monnier+emacs@gnu.org> (raw)
In-Reply-To: CAFsi02Qw9X1_LJqHf8vA3GCHuqVErShYt89j3AKrAvoCHaLhsg@mail.gmail.com

> Now I'm curious too... Would something like this work?
>
>  (let ((inhibit-quit t))
>    (setq process
>       (let ((inhibit-quit nil))
>          (ftp-setup-buffer host file))))

No.  The problem is not in the `setq` itself but in the fact that
a non-local exit from `ftp-setup-buffer` (e.g. because of `C-g`) will
cause `ftp-setup-buffer` not to return the process.

We should devise a more reliable API, tho I'm not completely sure what
it should look like.  Maybe

    (let ((list-of-created-processes nil))
      (unwind-protect ...
        (mapc #'delete-process list-of-created-processes)))

Where the low-level primitives which create processes add them to
`list-of-created-processes`.

But then this gets into trouble when some unrelated code is run during
`...` (e.g. via timers or whatnot) which creates unrelated processes, so
we'd need some extra care to make sure those processes don't get added
to "the same" `list-of-created-processes`.


        Stefan




  parent reply	other threads:[~2021-07-16 15:00 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-15 15:14 unwind-protect and inhibit-quit Felix Dietrich
2021-07-16  7:18 ` Eli Zaretskii
2021-07-16  8:10   ` Thibaut Verron
2021-07-16 11:19     ` Eli Zaretskii
2021-07-16 14:46       ` Felix Dietrich
2021-07-16 14:56         ` Felix Dietrich
2021-07-16 15:00     ` Stefan Monnier via Users list for the GNU Emacs text editor [this message]
2021-07-16 20:01       ` Thibaut Verron
2021-07-16 20:06         ` Stefan Monnier via Users list for the GNU Emacs text editor
2021-07-16 21:30       ` Felix Dietrich
2021-07-16 21:37         ` Stefan Monnier via Users list for the GNU Emacs text editor
2021-07-17 11:52           ` Felix Dietrich
2021-07-17  6:20         ` Eli Zaretskii
2021-07-17 15:46           ` Felix Dietrich
2021-07-17 16:34             ` Eli Zaretskii

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