Re: Increasing the rate of modeline display

[Artur Malabarba <bruce.connor.am@gmail.com>]

> You cannot increase the rate of redisplay, because it is already "as
> fast as possible": Emacs enters redisplay whenever the Lisp
> interpreter has nothing else to do.  There are no Emacs-induced delays
> that you could slash, AFAIK.

I think I had my wording wrong. General redisplay works fine (I see
the cursor blinking and stuff like that), but the mode-line content
doesn't update if I'm not interacting. I guess what I want is to
`force-mode-line-redisplay' around once per second (right now, it goes
without update indefinitely if the user is not interacting, see
below).

> In particular, any time the mode line changes it will be redisplayed
> immediately when Emacs has a chance to do so.  "Takes many seconds"
> sounds like something I never saw, except when some Lisp code is
> running during that time.

I ran the following after emacs -Q.

(add-to-list 'mode-line-format
         '(:eval (number-to-string (cadr (current-time))))
         'append)

This adds a number to the mode-line which changes at every second. If
I'm typing text (or otherwise interacting) then I see it updating
fine. If I just take my hands off the keyboard, then the number stops
updating indefinitely.