Don't search base directories if path starts with "/", "./" or
"../", but still do if the path simply starts with ".". Bail early
if HOME is needed but unset. Don't attempt to open the original
path in configOpen and dataOpen.
> When attempting to read a file, if for any reason a file in a certain
> directory is unaccessible, e.g. because the directory is non-existant,
> the file is non-existant or the user is not authorized to open the file,
> then the processing of the file in that directory should be skipped. If
> due to this a required file could not be found at all, the application
> may chose to present an error message to the user.
C. McEnroe