unofficial mirror of guile-devel@gnu.org 
 help / color / mirror / Atom feed
From: "Julian Graham" <joolean@gmail.com>
To: "Ludovic Courtès" <ludovic.courtes@laas.fr>, guile-devel@gnu.org
Subject: Re: thread cancellation, take 2
Date: Mon, 24 Sep 2007 11:39:10 -0400	[thread overview]
Message-ID: <2bc5f8210709240839k3069f572ne54d10f44680671@mail.gmail.com> (raw)
In-Reply-To: <87k5qg2ssf.fsf@laas.fr>

> I find it more elegant to use closures to that end.  I.e., when
> installing a handler, you'd write something like this:
>
>   (let ((cleanup (thread-cleanup-procedure (current-thread))))
>     (set-thread-cleanup-procedure! (current-thread)
>                                    (lambda ()
>                                      ;; invoke previous handler
>                                      (if (procedure? cleanup)
>                                          (cleanup))
>                                      ;; clean up...
>                                      )))
>
> There's a race here in case multiple threads try to change the cleanup
> procedure associated with that particular thread at the same time, but I
> suppose it is not an issue in practice.

Fair enough, re: closures.  But why should callers outside the current
thread be able to access that thread's cleanup handler procedure?
Maybe this isn't a realistic issue, but you could use this to "inject"
arbitrary code into a separate thread by setting the cleanup procedure
and immediately canceling the thread.  Why not treat the handler as
thread-specific data?


_______________________________________________
Guile-devel mailing list
Guile-devel@gnu.org
http://lists.gnu.org/mailman/listinfo/guile-devel


  reply	other threads:[~2007-09-24 15:39 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-09-20 14:30 thread cancellation, take 2 Julian Graham
2007-09-20 15:18 ` Ludovic Courtès
2007-09-20 15:36   ` Julian Graham
2007-09-23  5:16     ` Julian Graham
2007-09-23 10:42       ` Ludovic Courtès
2007-09-23 18:39         ` Julian Graham
2007-09-24 11:42           ` Ludovic Courtès
2007-09-24 15:39             ` Julian Graham [this message]
2007-09-24 20:17               ` Julian Graham
2007-09-26  4:03               ` Ludovic Courtès
2007-09-27  2:39                 ` Julian Graham
2007-10-18  0:41                   ` Julian Graham
2007-10-20 11:12                     ` Ludovic Courtès
2007-10-20 13:02                     ` Ludovic Courtès
2007-10-20 22:19                       ` Julian Graham
2007-10-21 13:03                         ` Ludovic Courtès
2007-10-21 13:11                           ` Ludovic Courtès
2007-10-23 14:16                             ` Julian Graham
2007-10-24  2:35                               ` Julian Graham
2007-10-29 22:04                                 ` Ludovic Courtès
2007-10-29 22:20                                   ` Julian Graham
2007-10-29 23:23                                     ` Neil Jerram
2007-10-30  9:35                                       ` Ludovic Courtès

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

  List information: https://www.gnu.org/software/guile/

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=2bc5f8210709240839k3069f572ne54d10f44680671@mail.gmail.com \
    --to=joolean@gmail.com \
    --cc=guile-devel@gnu.org \
    --cc=ludovic.courtes@laas.fr \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).