=head1 COMPARISON

This method of getting links has its advantages and disadvantages
compared to getting them from files.  The points of comparison are
given below.

=head2 indeterminate

We can never be sure whether we have really finished.  With files, we
just follow the directory structure.  With WWW pages, the index of a
directory may not match its contents.  There may be hidden resources,
that are never referenced from inside.  Even so, outside can know
about them so we may need to maintain them.

=head2 inefficient

Apart from the fact that this goes through the WWW server to find it's
files, and probably does this in a very random order, there is also a
need to use, within the program, an index of all of the links examined
so far.  This can use alot of disk-space.

=head2 follows real server space

The files seen from the outside are really in the locations that they
are seen from the outside in.. Looking at files can be deceptive
because the WWW server can be configured in almost anyway, and even
two files in a particular directory don't have to occur in anything
like the same location from outside.  In fact they could even be
served by different servers from different IP addresses.

=cut

