bug#4341: 23.1; M-x locate runs synchronously

[Juri Linkov <juri@jurta.org>]

>> Is it possible to avoid using "ls"?  If ls formatting is not needed,
>> then the output buffer will look like a Dired buffer with enabled
>> 'dired-hide-details-mode' that shows only file names.
>
> I guess it is possible, I have no clue.  It's what we do now.
>
> A downside is that developers would have to keep this in mind when
> working on dired, otherwise things may work only partially or break.
> For example, if you (in current Emacs master) mark files in a *locate*
> output buffer, they get marked and you can act on them, but marked files
> are not highlighted.
>
> OTOH, if we leave the corner case of non-existing files aside for now -
> when we do call ls (what would be the downsides?), we would get a fully
> functional dired support out of the box.
>
> Privately, I have adviced `locate' to insert the list of found files
> into a new dired buffer (by calling `dired' with the explicit list of
> files), and so far I find it better.  That is actually already all I can
> contribute so far.

Maybe this would be an improvement.  But sorry, I can't help in testing:
while slow `M-x locate' used to be a problem in the past, nowadays it
finishes within 1 sec, so I simply won't notice the difference :-)