bug#11993: Emacs frames on other display hang during recursive edit on a different display

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Please write in English if possible, as the Emacs maintainers

usually do not have translators for other languages.

Please describe exactly what actions triggered the bug, and

the precise symptoms of the bug.  If you can, give a recipe

starting from `emacs -Q':

    emacs -Q

        ...opens a frame (X Window)

        ...select that window, use it a bit to see that all works

        ESC-X make-frame-on-display

        ... type in display name

        ... note: in may case, the display is a different VNC session

        ... switch to the just opened emacs frame in that display, use it a bit

        to see that all works

        ... switch back, again, just to see that all works.

        ... in eother of the frames, type

        ESC-X recursive-edit

        ...  I am still able to work in the frame that initiated the recursive

        edit.

        ... However, in the other frames of the emacs, while I can select the

        frame (X Window), and the cursor changes from outline to filled, I

        cannot do anything useful.  The other frame(s) are hung: typing is not

        accepted, mouse clicks do not move the cursor.

        ... but the frame in which you typed recursive-edit still works

        ... switch back to that frame, type

        ESC-X exit-recursive-edit

        ... everything now works, in all frames.

    Further investigation shows that this hang occurs whenever the

    minibuffer is open in another frame.  I also find

        http://www.mail-archive.com/emacs-pretest-bug@gnu.org/msg08103.html

    to which Stallman responded:

        Re: Emacs hangs on current display when the minibuffer is active on another display

        Richard Stallman

        Wed, 27 Sep 2006 19:15:16 -0700

            If I leave the emacs on one

            display with the minibuffer active, emacs on the other display does

            not respond to anything until the minibuffer input is resolved (input

            entered, or quit).

        It is nearly impossible to fix this without making Emacs

        multi-threaded.  I hope that will be done some day, but I

        don't know if anyone is working on it.

    I suppose that I could give up and not report this bug.

    However, (a) reporting that this occurs with recursive-edit as well as

    minibuffer open may help the next person who encounters this bug, and

    (b) while I can imagine ways that the minibuffrer problem may be

    difficult to fix without multithreading (or good non-blocking

    asynchronous I/O), I must admit that I cannot imagine why recursive-edit

    would be like that.

    Also (c) I could swear that I *have* been able to use recursive-edit

    with multiple frames in the past, on older versions of emacs.  However, I

    cannot reproduce this at the moment - all of the different versions of

    emacs I have access to have this problem.

    (By the way, my apologies for mailing this bug report from Microsoft

    Outlook or Gmail, although it was prepared in EMACS.)

If Emacs crashed, and you have the Emacs process in the gdb debugger,

please include the output from the following gdb commands:

    `bt full' and `xbacktrace'.

For information about debugging Emacs, please read the file

/home/glew/import/emacs/emacs-24.1/install-dir-personal/share/emacs/24.1/etc/DEBUG.

In GNU Emacs 24.1.1 (x86_64-unknown-linux-gnu, GTK+ Version 2.10.4)

 of 2012-07-13 on mipscs587

Windowing system distributor `The XFree86 Project, Inc', version 11.0.40300000

Configured using:

 `configure '--with-gif=no'

 '--prefix=/home/glew/import/emacs/emacs-24.1/install-dir-personal''

Important settings:

  value of $LC_ALL: nil

  value of $LC_COLLATE: nil

  value of $LC_CTYPE: nil

  value of $LC_MESSAGES: nil

  value of $LC_MONETARY: nil

  value of $LC_NUMERIC: nil

  value of $LC_TIME: nil

  value of $LANG: C

  value of $XMODIFIERS: nil

  locale-coding-system: nil

  default enable-multibyte-characters: t

Major mode: Lisp Interaction

Minor modes in effect:

  tooltip-mode: t

  mouse-wheel-mode: t

  tool-bar-mode: t

  menu-bar-mode: t

  file-name-shadow-mode: t

  global-font-lock-mode: t

  font-lock-mode: t

  blink-cursor-mode: t

  auto-composition-mode: t

  auto-encryption-mode: t

  auto-compression-mode: t

  line-number-mode: t

  transient-mark-mode: t

Recent input:

<help-echo> <down-mouse-1> <mouse-1> <escape> x m a 

k e - f r a m e <tab> - o n <tab> <return> l o c a 

l h o s t L : 1 <backspace> <backspace> <backspace> 

: 1 2 <return> <switch-frame> <help-echo> <down-mouse-1> 

<mouse-1> <escape> x r e c u r s i v e - e d u <backspace> 

i t <return> <down-mouse-1> <mouse-1> <escape> x e 

x i t - r e c u r s i v e - e d i t <return> <switch-frame> 

<down-mouse-1> <mouse-1> <down-mouse-1> <mouse-1> <down-mouse-1> 

<mouse-1> q q q <down-mouse-1> <mouse-1> <backspace> 

<backspace> <backspace> <escape> x r e p o r t - e 

m a c s - b u g <return>

Recent messages:

For information about GNU Emacs and the GNU system, type C-h C-a.

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