'x-create-frame' succeeds, but 'x-open-connection' fails with same display argument

'x-create-frame' succeeds, but 'x-open-connection' fails with same display argument

[Herman]

Hi !

$ emacs --fg-daemon
$ emacsclient --eval "(terminal-list)"
(#<terminal 0 on initial_terminal>)
$ emacsclient --eval "(get-device-terminal nil)"
#<terminal 0 on initial_terminal>
$ emacsclient --eval "(x-display-list)"
nil
$ emacsclient --eval "(x-create-frame \`((display . ,(getenv \"DISPLAY\"))))"
#<frame *scratch* - GNU Emacs 0x55db73fd9c30>
$ emacsclient --eval "(terminal-list)"
(#<terminal 0 on initial_terminal> #<terminal 1 on :0.0>)
$ emacsclient --eval "(get-device-terminal nil)"
#<terminal 1 on :0.0>
$ emacsclient --eval "(x-display-list)"
(":0.0")
$ emacsclient --eval "(kill-emacs)"
$ emacs --fg-daemon
$ emacsclient --eval "(x-open-connection (getenv \"DISPLAY\"))"
nil
...
Debugger entered--Lisp error: (error "Display :0.0 does not exist")
  signal(error ("Display :0.0 does not exist"))
  error("Display %s does not exist" ":0.0")
  get-device-terminal(":0.0")
  frames-on-display-list(":0.0")
  font-setting-change-default-font(":0.0" nil)
  dynamic-setting-handle-config-changed-event((config-changed-event font-render ":0.0"))
  funcall-interactively(dynamic-setting-handle-config-changed-event (config-changed-event font-render ":0.0"))
  call-interactively(dynamic-setting-handle-config-changed-event nil [(config-changed-event font-render ":0.0")])
  command-execute(dynamic-setting-handle-config-changed-event nil [(config-changed-event font-render ":0.0")] t)

Emacs 29.1.

/---
30.2 Multiple Terminals topic in Elisp manual says, 'x-open-connection' can be tested for communication with a given X display. What I have missed ?

Thank you in advance for your help !

Re: 'x-create-frame' succeeds, but 'x-open-connection' fails with same display argument

[Po Lu]

Herman <mahlamytsike@gmail.com> writes:

> Hi !
>
> $ emacs --fg-daemon
> $ emacsclient --eval "(terminal-list)"
> (#<terminal 0 on initial_terminal>)
> $ emacsclient --eval "(get-device-terminal nil)"
> #<terminal 0 on initial_terminal>
> $ emacsclient --eval "(x-display-list)"
> nil
> $ emacsclient --eval "(x-create-frame \`((display . ,(getenv \"DISPLAY\"))))"
> #<frame *scratch* - GNU Emacs 0x55db73fd9c30>
> $ emacsclient --eval "(terminal-list)"
> (#<terminal 0 on initial_terminal> #<terminal 1 on :0.0>)
> $ emacsclient --eval "(get-device-terminal nil)"
> #<terminal 1 on :0.0>
> $ emacsclient --eval "(x-display-list)"
> (":0.0")
> $ emacsclient --eval "(kill-emacs)"
> $ emacs --fg-daemon
> $ emacsclient --eval "(x-open-connection (getenv \"DISPLAY\"))"
> nil
> ...
> Debugger entered--Lisp error: (error "Display :0.0 does not exist")
>   signal(error ("Display :0.0 does not exist"))
>   error("Display %s does not exist" ":0.0")
>   get-device-terminal(":0.0")
>   frames-on-display-list(":0.0")
>   font-setting-change-default-font(":0.0" nil)
>   dynamic-setting-handle-config-changed-event((config-changed-event font-render ":0.0"))
>   funcall-interactively(dynamic-setting-handle-config-changed-event (config-changed-event font-render ":0.0"))
>   call-interactively(dynamic-setting-handle-config-changed-event nil [(config-changed-event font-render ":0.0")])
>   command-execute(dynamic-setting-handle-config-changed-event nil [(config-changed-event font-render ":0.0")] t)
>
> Emacs 29.1.
>
> /--- 30.2 Multiple Terminals topic in Elisp manual says,
> 'x-open-connection' can be tested for communication with a given X
> display. What I have missed ?
>
> Thank you in advance for your help !

I think this is a bug in Emacs, since the display is opened but a font
configuration event arrives shortly after it does, and triggers some
form of bug where, as no frame on that display then exists,
get-device-terminal signals that the display in the configuration event
is nonexistent.

Re: 'x-create-frame' succeeds, but 'x-open-connection' fails with same display argument

[Eli Zaretskii]

> From: Po Lu <luangruo@yahoo.com>
> Cc: help-gnu-emacs@gnu.org
> Date: Mon, 04 Dec 2023 08:31:29 +0800
> 
> > Emacs 29.1.
> >
> > /--- 30.2 Multiple Terminals topic in Elisp manual says,
> > 'x-open-connection' can be tested for communication with a given X
> > display. What I have missed ?
> >
> > Thank you in advance for your help !
> 
> I think this is a bug in Emacs, since the display is opened but a font
> configuration event arrives shortly after it does, and triggers some
> form of bug where, as no frame on that display then exists,
> get-device-terminal signals that the display in the configuration event
> is nonexistent.

Please submit a bug report with all the details using
report-emacs-bug.

Thanks.