Bug#2904: install-info doesn't cope with nonexistent /usr/info/dir file
The install-info script does not deal gracefully with the case where
/usr/info/dir (which doesn't seem to reside in any package, and thus has
little if any protection from being overwritten) doesn't exist.
Where it would seem reasonable to silently create the file (possibly with
some number of default entries), install-info instead complains about
being unable to get a lock and falls over.
While I understand that it might be worth notifying the user that their
/usr/info/dir file has disappeared, this is _not_ a good way to do
it---it took me several tries before I realized what the actual problem
"Don't let me make you unhappy by failing to be contrary enough...."