Re: "Final" version of tty child frames

[Eli Zaretskii]

> From: Gerd Möllmann <gerd.moellmann@gmail.com>
> Cc: Jared Finder <jared@finder.org>,  Eli Zaretskii <eliz@gnu.org>,
>   emacs-devel@gnu.org
> Date: Tue, 14 Jan 2025 10:37:24 +0100
> 
> Maybe I have an idea, but that is only based on memories how things were
> decades ago.
> 
> Around xdisp.c:20500, there should be something like this in master:
> 
>   /* Handle case where text has not changed, only point, and it has
>      not moved off the frame, and we are not retrying after hscroll.
>      (current_matrix_up_to_date_p is true when retrying.)  */
>   if (current_matrix_up_to_date_p
>       && (rc = try_cursor_movement (window, startp, &temp_scroll_step),
>         rc != CURSOR_MOVEMENT_CANNOT_BE_USED))
>     {
> 
> What happens if you add "false && " to the if-condition so that the body
> isn't executed?

In a build configured with --enable-checking=glyphs, one can simply
set inhibit-try-cursor-movement non-nil to cause try_cursor_movement
give up.