Re: How to get X Window id from within Emacs?

[Po Lu <luangruo@yahoo.com>]

Eli Zaretskii <eliz@gnu.org> writes:

>> Date: Sun, 15 Dec 2024 20:52:13 +0300
>> From: Jean Louis <bugs@gnu.support>
>> 
>> The standard shell commend `xwininfo' gives me the Window id, such as
>> 0x2e000ac and then I can run shell command like `xdotool' to activate
>> the Emacs window:
>> 
>> $ xwininfo 
>> 
>> xwininfo: Please select the window about which you
>>           would like information by clicking the
>>           mouse in that window.
>> 
>> xwininfo: Window id: 0x2e000ac "*shell* - GNU Emacs at lco2"
>> 
>> after switching to other workspace, then I can still do:
>> 
>> $ xdotool windowactivate 0x2e000ac
>> 
>> and I would return to Emacs X Window.
>> 
>> Is there a way to get the Window ID from within Emacs?
>
> There's the window-id frame parameter, although I'm not sure it is
> universally available.  Try
>
>   M-: (frame-parameter nil 'window-id) RET

This is the ID of Emacs's "inner window", where it displays buffer text
and decorations.  The `outer-window-id' frame parameter supplies a
window ID that is suitable for external programs such as xdotool.