auto-update of Info dir file?

["Drew Adams" <drew.adams@oracle.com>]

I haven't thought this through much or tried to investigate how it might
work, but it occurred to me that `info' might do something like this:

For each directory in `Info-directory-list', for each top-level file in the
directory (i.e. whose name doesn't end in "-N", N=1,2,3...): Check if there
is a corresponding entry in the Info `dir' file (in
`Info-dir-contents-directory'), and, if not, add one.

Perhaps there is already part of the mechanism for doing this. When I look
in some Info files now I see (START|END)-INFO-DIR-ENTRY, which makes me
think there must already be a means of adding the entry. Perhaps all that's
missing is to have `info' do that on the fly automatically for each
top-level Info file in the directories of `Info-directory-list'.

Some Info files might not have a (START|END)-INFO-DIR-ENTRY, in which case
only a simple entry would be added - say, using the file name as the link
itself and leaving the description blank. (Or perhaps a description could be
gleaned from the Info file.)

I mention this because of a question in help-gnu-emacs today and a reply
advising the user to add the entry to the `dir' file. Why not have Emacs do
that automatically, so the only user task would be to add the Info files to
the directory?

If this were costly in performance, it might be done only on first use of
`info' in a session.