to securely wipe the device). It should be sufficient to remove
any partition tables, filesystem superblocks and so on.
+=head2 zerofree
+
+ zerofree device
+
+This runs the I<zerofree> program on C<device>. This program
+claims to zero unused inodes and disk blocks on an ext2/3
+filesystem, thus making it possible to compress the filesystem
+more effectively.
+
+You should B<not> run this program if the filesystem is
+mounted.
+
+It is possible that using this program can damage the filesystem
+or data on the filesystem.
+