Re: filenotify.el

[Michael Albinus <michael.albinus@gmx.de>]

Davis Herring <herring@lanl.gov> writes:

> An addendum to my own agitation: if there's a way to prevent gfilenotify
> from polling (or if we add Lisp polling to filenotify.el in the future),
> `file-notify-add-watch' could benefit from a don't-poll flag, either as
> an additional argument or as a new accepted symbol in FLAGS.  That way
> we can (probably) also avoid having a
> `file-notify-supported-without-polling-p'.

gfilenotify.c uses g_file_monitor from glib/gio. This does polling for
mounted objects only in case the object to be watched is a regular
file. For directories, polling is not supported (and the function
returns an error in case there is no native file notification mechanism
for that directory).

filenotify.el tries always to watch directories. No polling therefore,
at least for the time being. Whether we want introduce explicit polling
depends on the request from users. For now, I have no plans.

It might be different when the file/directory to be watched is located
on a remote host. Then it depends on the implementation of the
respective file handler, whether it uses polling, or not.

> Davis

Best regards, Michael.