bug#29513: 25.2; find-dired-centinel

[Eli Zaretskii <eliz@gnu.org>]

> Date: Fri, 1 Dec 2017 10:28:02 -0600
> From: "Roland Winkler" <winkler@gnu.org>
> Cc: 29513@debbugs.gnu.org
> 
> On Fri Dec 1 2017 Eli Zaretskii wrote:
> > IMO, if this is deemed a useful feature, it should be optional, as it
> > will cause files to move on display during the time the shell commands
> > is running, something that users might find annoying (I certainly
> > would).
> 
> In my code, nothing happens while the shell command is running.  The
> sorting happens only once when find has finished its job.  But it
> would certainly be fine with me to have a user option such as
> find-dired-sort for enabling / disabling this feature.

Maybe we should simply provide a defcustom, which is a function called
by the sentinel.  Then users could customize what happens after the
files are all collected, be it sort the results or anything else.  The
advantage will be that we won't need to support every possible tweak
of post-processing in core.