+=head2 cp
+
+ cp src dest
+
+This copies a file from C<src> to C<dest> where C<dest> is
+either a destination filename or destination directory.
+
+=head2 cp-a
+
+ cp-a src dest
+
+This copies a file or directory from C<src> to C<dest>
+recursively using the C<cp -a> command.
+
+=head2 debug
+
+ debug subcmd 'extraargs ...'
+
+The C<debug> command exposes some internals of
+C<guestfsd> (the guestfs daemon) that runs inside the
+qemu subprocess.
+
+There is no comprehensive help for this command. You have
+to look at the file C<daemon/debug.c> in the libguestfs source
+to find out what you can do.
+
+=head2 dmesg
+
+ dmesg
+
+This returns the kernel messages (C<dmesg> output) from
+the guest kernel. This is sometimes useful for extended
+debugging of problems.
+
+Another way to get the same information is to enable
+verbose messages with C<set-verbose> or by setting
+the environment variable C<LIBGUESTFS_DEBUG=1> before
+running the program.
+
+=head2 download
+
+ 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<upload>, C<cat>.
+
+Use C<-> instead of a filename to read/write from stdin/stdout.
+
+=head2 drop-caches
+
+ 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.
+
+=head2 equal
+
+ equal file1 file2
+
+This compares the two files C<file1> and C<file2> and returns
+true if their content is exactly equal, or false otherwise.
+
+The external L<cmp(1)> program is used for the comparison.
+
+=head2 exists
+
+ exists path
+
+This returns C<true> if and only if there is a file, directory
+(or anything) with the given C<path> name.
+
+See also C<is-file>, C<is-dir>, C<stat>.
+
+=head2 file
+
+ file path
+
+This call uses the standard L<file(1)> command to determine
+the type or contents of the file. This also works on devices,
+for example to find out whether a partition contains a filesystem.
+
+The exact command which runs is C<file -bsL path>. Note in
+particular that the filename is not prepended to the output
+(the C<-b> option).
+
+=head2 fsck
+
+ fsck fstype device
+
+This runs the filesystem checker (fsck) on C<device> which
+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>.
+
+Notes:
+
+=over 4
+
+=item *
+
+Multiple status codes can be summed together.
+
+=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>.
+