Re: [PATCH]saveplace.el: forget saved places for unreadable files

[Richard Stallman]

    Reasons this may not be desirable:

     * removable/network drives, tarballs: files with useful saved places
       may not always be present

     * file-readable-p can be slow applied to certain volumes, such as
       CD-ROM drives.  The first time I ran it, on my formerly 1000-item
       save-place-alist, emacs hung on exit while the CD-ROM spun up for
       the necessary tests

This suggests it would be useful to add a feature for specifying
patterns of file names that should not be tested.  Perhaps there
can be a default pattern that matches all remote file names, etc.
Then the feature could be enabled by default.  What do you think?