What causes redisplay?

What causes redisplay?

[Lennart Borgman]

In mumamo I have to temporarily narrow the buffer when turning on a
major mode in chunk. However under some circumstances the buffer is
redisplayed during this short temporarily narrowing and I wonder why.
It looks like a bug somewhere in Emacs to me, but I am not sure.

The redisplay happens if I add this

   (add-hook 'python-mode-hook 'turn-on-eldoc-mode)

This runs a subprocess with python and I guess it has something to do with this.

I am seeing this with an Emacs compiled from sources checked out 2010-01-26.

PS: I can work around this by temporarily setting inhibit-redisplay to
t during the narrowing, but I am not sure what trouble that may cause.

Re: What causes redisplay?

[Eli Zaretskii]

> From: Lennart Borgman <lennart.borgman@gmail.com>
> Date: Mon, 1 Feb 2010 11:45:27 +0100
> 
> The redisplay happens if I add this
> 
>    (add-hook 'python-mode-hook 'turn-on-eldoc-mode)
> 
> This runs a subprocess with python and I guess it has something to do with this.

I see no surprises here: AFAIK, running a subprocess always triggers
redisplay.

Re: What causes redisplay?

[Lennart Borgman]

On Mon, Feb 1, 2010 at 8:44 PM, Eli Zaretskii <eliz@gnu.org> wrote:
>> From: Lennart Borgman <lennart.borgman@gmail.com>
>> Date: Mon, 1 Feb 2010 11:45:27 +0100
>>
>> The redisplay happens if I add this
>>
>>    (add-hook 'python-mode-hook 'turn-on-eldoc-mode)
>>
>> This runs a subprocess with python and I guess it has something to do with this.
>
> I see no surprises here: AFAIK, running a subprocess always triggers
> redisplay.


Thanks Eli, I was suspecting something like that, but I didn't know for sure.

What is the reason that running a subprocess triggers redisplay?

Re: What causes redisplay?

[Stefan Monnier]

> What is the reason that running a subprocess triggers redisplay?

I'd be interested to know as well,


        Stefan