bug#19576: write-file writes the wrong buffer

[Eli Zaretskii]

> Date: Sun, 22 Nov 2015 18:46:19 +0100
> From: martin rudalics <rudalics@gmx.at>
> CC: acm@muc.de, 19576@debbugs.gnu.org, andlind@gmail.com, 
>  juri@linkov.net
> 
>  > I couldn't think of any situation that would cause that.  It would
>  > require a resize of windows outside redisplay that would also cause
>  > redisplay to decide that the mini-window needs to be resized.  If you
>  > can come up with a recipe for this, we should indeed remove the "just
>  > once" promise.
> 
> A silly example with emacs -Q is
> 
> (defvar fun 0)
> 
> (defun fun (frame)
>    "..."
>    (message "\n%s\n" (setq fun (1+ fun))) (ding))
> 
> (add-hook 'window-size-change-functions 'fun)
> 
> This gets me complete erratic behavior when moving point.

Maybe I'm blind, but I don't see anything erratic.

> Another example is
> 
> (defvar fun 0)
> 
> (defun fun (frame)
>    "..."
>    (message "%s" (setq fun (1+ fun))) (ding))
> 
> (add-hook 'window-size-change-functions 'fun)
> 
> (progn
>    (tool-bar-mode -1)
>    (sit-for 1)
>    (tool-bar-mode 1))
> 
> With my patch for bug#21975 this runs ‘fun’ twice when the tool-bar is
> reenabled.  Likely due to my calculations of the real tool bar height.

I see that, but does that mean we should remove the "once only"
promise?