C<value> can be NULL.
+=item $h->download ($remotefilename, $filename);
+
+Download file C<remotefilename> and save it as C<filename>
+on the local machine.
+
+C<filename> can also be a named pipe.
+
+See also C<$h-E<gt>upload>, C<$h-E<gt>cat>.
+
=item $existsflag = $h->exists ($path);
This returns C<true> if and only if there is a file, directory
Some internal mounts are not unmounted by this call.
+=item $h->upload ($filename, $remotefilename);
+
+Upload local file C<filename> to C<remotefilename> on the
+filesystem.
+
+C<filename> can also be a named pipe.
+
+See also C<$h-E<gt>download>.
+
=item $h->vgcreate ($volgroup, \@physvols);
This creates an LVM volume group called C<volgroup>