Re: Merging the pgtk branch

[Eli Zaretskii <eliz@gnu.org>]

> Date: Tue, 30 Nov 2021 00:41:15 +0900 (JST)
> Cc: emacs-devel@gnu.org
> From: Yuuki Harano <masm+emacs@masm11.me>
> 
> >>> @@ -4775,10 +4779,17 @@ gui_set_border_width (struct frame *f, Lisp_Object arg, Lisp_Object oldval)
> >>>    if (border_width == f->border_width)
> >>>      return;
> >>  
> >>> +#ifndef HAVE_PGTK
> >>>    if (FRAME_NATIVE_WINDOW (f) != 0)
> >>>      error ("Cannot change the border width of a frame");
> >>> +#endif
> >>  
> >>>    f->border_width = border_width;
> >>> +
> >>> +#ifdef HAVE_PGTK
> >>> +  if (FRAME_TERMINAL (f)->frame_rehighlight_hook)
> >>> +    (*FRAME_TERMINAL (f)->frame_rehighlight_hook) (f);
> >>> +#endif
> >> 
> >> Why is the above done only for PGTK?
> > 
> > I'm sorry.  I forgot the reason.
> 
> I thought that gui_set_border_width could change the border width of a frame.
> But there is the code:
> ---
>     if (FRAME_NATIVE_WINDOW (f) != 0)
>       error ("Cannot change the border width of a frame");
> ---
> I was confused, and added #ifndef around it.
> 
> I don't know about the function.
> What is it for?

It's for setting the width of the "external border" of the frame,
something that window managers generally disallow.  Doesn't PGTK
define FRAME_NATIVE_WINDOW to return non-zero for any GUI frame?  If
so, you don't have to #ifdef this, it will work as with any other
window-system.

Thanks.