bug#35418: [PATCH] Don't poll auto-revert files that use notification

[Mattias Engdegård]

8 maj 2019 kl. 14.35 skrev Eli Zaretskii <eliz@gnu.org>:
> 
>> An example of a generalisation: We could add a buffer-specific variable that 
>> tells autorevert that yes, this buffer can rely on directory notifications 
>> despite not having a buffer-file-name. All modes to which this applies would 
>> need to set that variable.
>> 
>> I don't think there is a passive condition, and furthermore, because of the 
>> nature of directory notifications, any mode that qualifies is likely to be 
>> some kind of variation on Dired: a buffer whose contents is determined by 
>> the set of files in its default-directory, but not their data.
> 
> OK, so how about adding such a variable as part of this improvement?

If it's all the same to you, I'd like to keep it separate. This patch fixes a 
bug: some buffers, like Buffer Menu, are not updated automatically at all when 
`auto-revert-avoid-polling' is set.
What you are talking about is making some dired-like buffers update 2.5 s 
faster on average, if they set the right variable.

> Or maybe it's better to have a special property on the mode's symbol?

Maybe a variable goes better with `revert-buffer-function' and 
`buffer-stale-function' already in use by autorevert for related purposes, 
although I'm eager to hear what Michael has to say (about this and everything 
else).