C<value> can be NULL.
+=item $h->cp ($src, $dest);
+
+This copies a file from C<src> to C<dest> where C<dest> is
+either a destination filename or destination directory.
+
+=item $h->cp_a ($src, $dest);
+
+This copies a file or directory from C<src> to C<dest>
+recursively using the C<cp -a> command.
+
=item $result = $h->debug ($subcmd, \@extraargs);
The C<$h-E<gt>debug> command exposes some internals of
See also C<$h-E<gt>upload>, C<$h-E<gt>cat>.
+=item $h->drop_caches ($whattodrop);
+
+This instructs the guest kernel to drop its page cache,
+and/or dentries and inode caches. The parameter C<whattodrop>
+tells the kernel what precisely to drop, see
+L<http://linux-mm.org/Drop_Caches>
+
+Setting C<whattodrop> to 3 should drop everything.
+
+This automatically calls L<sync(2)> before the operation,
+so that the maximum guest memory is freed.
+
=item $existsflag = $h->exists ($path);
This returns C<true> if and only if there is a file, directory
should have filesystem type C<fstype>.
The returned integer is the status. See L<fsck(8)> for the
-list of status codes from C<fsck>, and note that multiple
-status codes can be summed together.
+list of status codes from C<fsck>.
+
+Notes:
+
+=over 4
+
+=item *
+
+Multiple status codes can be summed together.
-It is entirely equivalent to running C<fsck -a -t fstype device>.
-Note that checking or repairing NTFS volumes is not supported
+=item *
+
+A non-zero return code can mean "success", for example if
+errors have been corrected on the filesystem.
+
+=item *
+
+Checking or repairing NTFS volumes is not supported
(by linux-ntfs).
+=back
+
+This command is entirely equivalent to running C<fsck -a -t fstype device>.
+
=item $autosync = $h->get_autosync ();
Get the autosync flag.
This returns the verbose messages flag.
+=item $h->grub_install ($root, $device);
+
+This command installs GRUB (the Grand Unified Bootloader) on
+C<device>, with the root directory being C<root>.
+
=item $busy = $h->is_busy ();
This returns true iff this handle is busy processing a command
Some internal mounts are not shown.
+=item $h->mv ($src, $dest);
+
+This moves a file from C<src> to C<dest> where C<dest> is
+either a destination filename or destination directory.
+
=item $h->pvcreate ($device);
This creates an LVM physical volume on the named C<device>,
of somewhere between 2MB and 4MB. To transfer large files you should use
FTP.
+=item $h->zero ($device);
+
+This command writes zeroes over the first few blocks of C<device>.
+
+How many blocks are zeroed isn't specified (but it's I<not> enough
+to securely wipe the device). It should be sufficient to remove
+any partition tables, filesystem superblocks and so on.
+
=cut
1;