* url.el blocks Gnus+nnrss @ 2005-01-13 12:16 Katsumi Yamaoka 2005-01-13 14:35 ` Stefan Monnier 0 siblings, 1 reply; 3+ messages in thread From: Katsumi Yamaoka @ 2005-01-13 12:16 UTC (permalink / raw) Cc: ding Hi, Several people reported that Gnus hangs if they subscribe to nnrss groups. nnrss is a back end which uses the url ELisp package by default and enables to read rss feeds as if they were newsgroups. When starting Gnus or typing `g' (gnus-group-get-new-news), it gets into the infinite loop. The reason the problem arises is stated in the `url-retrieve-synchronously' section of the url.el file as follows: ;; Quoth Stef: ;; It turns out that the problem seems to be that the (sit-for ;; 0.1) below doesn't actually process the data: instead it ;; returns immediately because there is keyboard input ;; waiting, so we end up spinning endlessly waiting for the ;; process to finish while not letting it finish. ;; However, raman claims that it blocks Emacs with Emacspeak ;; for unexplained reasons. Put back for his benefit until ;; someone can understand it. ;; (sleep-for 0.1) (sit-for 0.1)) I don't know why it sticks to `sleep-for' or `sit-for'. Although both process data, there are adverse effects as the comment mentioned. Isn't the function which should process data from the network `accept-process-output'? I tried it there and confirmed it solves the problem. Since I don't have Emacspeak, I'm not sure whether it doesn't trouble Emacspeak users, though. The patch is here: *** url.el~ Sun Nov 21 22:23:54 2004 --- url.el Thu Jan 13 12:15:19 2005 *************** *** 177,194 **** (while (not retrieval-done) (url-debug 'retrieval "Spinning in url-retrieve-synchronously: %S (%S)" retrieval-done asynch-buffer) ! ;; Quoth Stef: ! ;; It turns out that the problem seems to be that the (sit-for ! ;; 0.1) below doesn't actually process the data: instead it ! ;; returns immediately because there is keyboard input ! ;; waiting, so we end up spinning endlessly waiting for the ! ;; process to finish while not letting it finish. ! ! ;; However, raman claims that it blocks Emacs with Emacspeak ! ;; for unexplained reasons. Put back for his benefit until ! ;; someone can understand it. ! ;; (sleep-for 0.1) ! (sit-for 0.1)) asynch-buffer))) (defun url-mm-callback (&rest ignored) --- 177,183 ---- (while (not retrieval-done) (url-debug 'retrieval "Spinning in url-retrieve-synchronously: %S (%S)" retrieval-done asynch-buffer) ! (accept-process-output (get-buffer-process asynch-buffer) 0 100000 1)) asynch-buffer))) (defun url-mm-callback (&rest ignored) ^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: url.el blocks Gnus+nnrss 2005-01-13 12:16 url.el blocks Gnus+nnrss Katsumi Yamaoka @ 2005-01-13 14:35 ` Stefan Monnier 2005-01-13 22:39 ` Katsumi Yamaoka 0 siblings, 1 reply; 3+ messages in thread From: Stefan Monnier @ 2005-01-13 14:35 UTC (permalink / raw) Cc: ding, emacs-devel > Several people reported that Gnus hangs if they subscribe to > nnrss groups. nnrss is a back end which uses the url ELisp > package by default and enables to read rss feeds as if they were > newsgroups. I've myself been using the patch below for a while now (it basically does the same as yours, except it hoists the get-buffer-process outside the loop and it removes the timeout since it shouldn't be needed now that Emacs knows what we're waiting for). I've just installed it. Stefan --- orig/lisp/url/url.el +++ mod/lisp/url/url.el @@ -1,6 +1,7 @@ ;;; url.el --- Uniform Resource Locator retrieval tool -;; Copyright (c) 1996,1997,1998,1999,2001,2004 Free Software Foundation, Inc. +;; Copyright (c) 1996, 1997, 1998, 1999, 2001, 2004, 2005 +;; Free Software Foundation, Inc. ;; Author: Bill Perry <wmperry@gnu.org> ;; Keywords: comm, data, processes, hypermedia @@ -169,26 +169,24 @@ (url-debug 'retrieval "Synchronous fetching done (%S)" (current-buffer)) (setq retrieval-done t asynch-buffer (current-buffer))))) - (if (not asynch-buffer) + (let ((proc (and asynch-buffer (get-buffer-process asynch-buffer)))) + (if (null proc) ;; We do not need to do anything, it was a mailto or something ;; similar that takes processing completely outside of the URL ;; package. nil (while (not retrieval-done) (url-debug 'retrieval "Spinning in url-retrieve-synchronously: %S (%S)" retrieval-done asynch-buffer) - ;; Quoth Stef: - ;; It turns out that the problem seems to be that the (sit-for - ;; 0.1) below doesn't actually process the data: instead it - ;; returns immediately because there is keyboard input - ;; waiting, so we end up spinning endlessly waiting for the - ;; process to finish while not letting it finish. - - ;; However, raman claims that it blocks Emacs with Emacspeak - ;; for unexplained reasons. Put back for his benefit until - ;; someone can understand it. - ;; (sleep-for 0.1) - (sit-for 0.1)) + ;; We used to use `sit-for' here, but in some cases it wouldn't + ;; work because apparently pending keyboard input would always + ;; interrupt it before it got a chance to handle process input. + ;; `sleep-for' was tried but it lead to other forms of + ;; hanging. --Stef + (unless (accept-process-output proc) + ;; accept-process-output returned nil, maybe because the process + ;; exited (and may have been replaced with another). + (setq proc (get-buffer-process asynch-buffer))))) asynch-buffer))) (defun url-mm-callback (&rest ignored) ^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: url.el blocks Gnus+nnrss 2005-01-13 14:35 ` Stefan Monnier @ 2005-01-13 22:39 ` Katsumi Yamaoka 0 siblings, 0 replies; 3+ messages in thread From: Katsumi Yamaoka @ 2005-01-13 22:39 UTC (permalink / raw) Cc: emacs-devel, ding >>>>> In <87pt09v2m1.fsf-monnier+emacs@gnu.org> Stefan Monnier wrote: > I've myself been using the patch below for a while now (it basically does > the same as yours, except it hoists the get-buffer-process outside the loop > and it removes the timeout since it shouldn't be needed now that Emacs knows > what we're waiting for). > I've just installed it. Excellent. I confirmed the problem has gone. Thank you. ^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2005-01-13 22:39 UTC | newest] Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2005-01-13 12:16 url.el blocks Gnus+nnrss Katsumi Yamaoka 2005-01-13 14:35 ` Stefan Monnier 2005-01-13 22:39 ` Katsumi Yamaoka
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