Re: xterm [menu] key definition

[Ergus]

On Tue, Aug 24, 2021 at 08:28:22PM +0300, Eli Zaretskii wrote:
> > Date: Tue, 24 Aug 2021 18:40:36 +0200
> > Cc: Stefan Monnier <monnier@iro.umontreal.ca>,
> >  emacs-devel <emacs-devel@gnu.org>
> > From:  Ergus via "Emacs development discussions." <emacs-devel@gnu.org>
> >
> > Just to clarify.
> >
> > What I am proposing is as simple as the attached patch.
> >
> > I won't expect any complain about the change, but if so we then may
> > decide to do something like an alias between [menu] and [print]:

Hi Eli:

It is fine for me. Actually I didn't add the [PATCH] flag to the Subject
of the message because the patch was only to illustrate the proposal
with specific code, not more and more words and explications.

> Look, we need some kind of evidence that this is TRT, some document
> that describes that key, or explains why urxvt and xterm behave
> differently, or who and why made the current code as it is.  We cannot
> make this change in xterm.el just because you think it's right and it
> suits your personal system configuration.  The code we have wins by
> default, unless you can come up with a clear reason explaining why it
> is wrong.

I am not saying the current code is wrong. Just that the so called
[print] key does not exist while the same key is seen as [menu] in gui.

I expect that emacs user gets the similar behavior when they press the
menu key. Either in tty, tui or gui... or at least as consistent as
possible. (either redefining ^[[29~ as [menu] or binding the context
menu to [print]... I have already this on my config... obviously I
prefer the first alternative)

I already wrote to Thomas Dickey (xterm maintainer) some days ago about
this:

=================================

On Wed, Aug 18, 2021 at 08:38:44PM -0400, Thomas Dickey wrote:
> On Wed, Aug 18, 2021 at 09:46:53PM +0200, Ergus wrote:
> > Hi:
> >
> > I use emacs and I have noticed that when using xterm and I press the
> > menu key, emacs is detecting <print> instead. (emacs just added a
> > context menu and it could be probably bind to the menu key)
> >
> > cat shows that xterm sends ^[[29~ But I can't find information if this
> > is the right one or how to debug this.
>
> hmm - I didn't notice, but in a quick check the key which I guessed is
> "menu" (between the Windows key and the Ctrl key on the right-side of
> my keyboard) does send ^[[29~ and xev says that's "Menu":
>
> --------------------------------------------------------------------------------
> KeyPress event, serial 34, synthetic NO, window 0xc00001,
>    root 0x111, subw 0xc00002, time 60750193, (37,34), root:(37,57),
>    state 0x0, keycode 118 (keysym 0xff67, Menu), same_screen YES,
>    XLookupString gives 0 bytes:
>    XmbLookupString gives 0 bytes:
>    XFilterEvent returns: False
>
> KeyRelease event, serial 34, synthetic NO, window 0xc00001,
>    root 0x111, subw 0xc00002, time 60750321, (37,34), root:(37,57),
>    state 0x0, keycode 118 (keysym 0xff67, Menu), same_screen YES,
>    XLookupString gives 0 bytes:
>    XFilterEvent returns: False
>
> KeyPress event, serial 34, synthetic NO, window 0xc00001,
>    root 0x111, subw 0xc00002, time 60750537, (37,34), root:(37,57),
>    state 0x0, keycode 118 (keysym 0xff67, Menu), same_screen YES,
>    XLookupString gives 0 bytes:
>    XmbLookupString gives 0 bytes:
>    XFilterEvent returns: False
> --------------------------------------------------------------------------------
>
> But in the terminal description, I'd not assigned anything to that.
> It's not a numbered function key, and terminfo doesn't have a standard
> "menu" key (I could add one, but had overlooked this :-).
>
> Emacs does.  Someone was telling me recently about something related
> to xterm, so I've a current source.  In that, I see this, with grep:
>
> lisp/term/lk201.el:35:    (define-key map "\e[29~" [menu])
> lisp/term/xterm.el:353:    (define-key map "\e[29~" [print])
> lisp/term/rxvt.el:67:    (define-key map "\e[29~" [S-f6])
>
> which is kind of old (git blame tells me):
>
> 0ba6bcb1d6e (Stefan Monnier    2007-09-07 19:47:46 +0000  353)
>
> but the first match shows the binding that you'd like to have.
>
> I don't use emacs, but suppose that you can add that definition
> to your custom settings, and get the menu that you expect.
>
> --
> Thomas E. Dickey <dickey@invisible-island.net>
> https://invisible-island.net
> ftp://ftp.invisible-island.net

=================================

> The rest of the change, i.e. binding the menu to the <menu> key, is
> fine by me.  But not the change in xterm.el, not without a very good
> explanation.
>
> Okay?

The other change I propose is the S-<f6> instead of S-<f10> and for that
we have all the evidence that urxvt binds the same escape sequence to
S-<f6> (since we do:

lisp/term/rxvt.el:67:    (define-key map "\e[29~" [S-f6])

and "\e[29~" is what the menu key sends by default)

Otherwise we will need to request to all the compatible terminals around
to update their terminfo.. a very long process that will delay for years
until all the systems in all the servers will be updated.

Best,
Ergus