of somewhere between 2MB and 4MB. To transfer large files you should use
FTP.
+=head2 guestfs_checksum
+
+ char *guestfs_checksum (guestfs_h *handle,
+ const char *csumtype,
+ const char *path);
+
+This call computes the MD5, SHAx or CRC checksum of the
+file named C<path>.
+
+The type of checksum to compute is given by the C<csumtype>
+parameter which must have one of the following values:
+
+=over 4
+
+=item C<crc>
+
+Compute the cyclic redundancy check (CRC) specified by POSIX
+for the C<cksum> command.
+
+=item C<md5>
+
+Compute the MD5 hash (using the C<md5sum> program).
+
+=item C<sha1>
+
+Compute the SHA1 hash (using the C<sha1sum> program).
+
+=item C<sha224>
+
+Compute the SHA224 hash (using the C<sha224sum> program).
+
+=item C<sha256>
+
+Compute the SHA256 hash (using the C<sha256sum> program).
+
+=item C<sha384>
+
+Compute the SHA384 hash (using the C<sha384sum> program).
+
+=item C<sha512>
+
+Compute the SHA512 hash (using the C<sha512sum> program).
+
+=back
+
+The checksum is returned as a printable string.
+
+This function returns a string, or NULL on error.
+I<The caller must free the returned string after use>.
+
=head2 guestfs_chmod
int guestfs_chmod (guestfs_h *handle,
Subsequent elements are parameters. The list must be
non-empty (ie. must contain a program name).
+The return value is anything printed to I<stdout> by
+the command.
+
+If the command returns a non-zero exit status, then
+this function returns an error message. The error message
+string is the content of I<stderr> from the command.
+
The C<$PATH> environment variable will contain at least
C</usr/bin> and C</bin>. If you require a program from
another location, you should provide the full path in the
This function returns a string, or NULL on error.
I<The caller must free the returned string after use>.
+Because of the message protocol, there is a transfer limit
+of somewhere between 2MB and 4MB. To transfer large files you should use
+FTP.
+
=head2 guestfs_command_lines
char **guestfs_command_lines (guestfs_h *handle,
(like L<environ(3)>), or NULL if there was an error.
I<The caller must free the strings and the array after use>.
+Because of the message protocol, there is a transfer limit
+of somewhere between 2MB and 4MB. To transfer large files you should use
+FTP.
+
=head2 guestfs_config
int guestfs_config (guestfs_h *handle,
This function returns 0 on success or -1 on error.
+=head2 guestfs_cp
+
+ int guestfs_cp (guestfs_h *handle,
+ const char *src,
+ const char *dest);
+
+This copies a file from C<src> to C<dest> where C<dest> is
+either a destination filename or destination directory.
+
+This function returns 0 on success or -1 on error.
+
+=head2 guestfs_cp_a
+
+ int guestfs_cp_a (guestfs_h *handle,
+ const char *src,
+ const char *dest);
+
+This copies a file or directory from C<src> to C<dest>
+recursively using the C<cp -a> command.
+
+This function returns 0 on success or -1 on error.
+
+=head2 guestfs_debug
+
+ char *guestfs_debug (guestfs_h *handle,
+ const char *subcmd,
+ char * const* const extraargs);
+
+The C<guestfs_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.
+
+This function returns a string, or NULL on error.
+I<The caller must free the returned string after use>.
+
+=head2 guestfs_dmesg
+
+ char *guestfs_dmesg (guestfs_h *handle);
+
+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<guestfs_set_verbose> or by setting
+the environment variable C<LIBGUESTFS_DEBUG=1> before
+running the program.
+
+This function returns a string, or NULL on error.
+I<The caller must free the returned string after use>.
+
=head2 guestfs_download
int guestfs_download (guestfs_h *handle,
This function returns 0 on success or -1 on error.
+=head2 guestfs_drop_caches
+
+ int guestfs_drop_caches (guestfs_h *handle,
+ int 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.
+
+This function returns 0 on success or -1 on error.
+
+=head2 guestfs_e2fsck_f
+
+ int guestfs_e2fsck_f (guestfs_h *handle,
+ const char *device);
+
+This runs C<e2fsck -p -f device>, ie. runs the ext2/ext3
+filesystem checker on C<device>, noninteractively (C<-p>),
+even if the filesystem appears to be clean (C<-f>).
+
+This command is only needed because of C<guestfs_resize2fs>
+(q.v.). Normally you should use C<guestfs_fsck>.
+
+This function returns 0 on success or -1 on error.
+
+=head2 guestfs_end_busy
+
+ int guestfs_end_busy (guestfs_h *handle);
+
+This sets the state to C<READY>, or if in C<CONFIG> then it leaves the
+state as is. This is only used when implementing
+actions using the low-level API.
+
+For more information on states, see L<guestfs(3)>.
+
+This function returns 0 on success or -1 on error.
+
+=head2 guestfs_equal
+
+ int guestfs_equal (guestfs_h *handle,
+ const char *file1,
+ const char *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.
+
+This function returns a C truth value on success or -1 on error.
+
=head2 guestfs_exists
int guestfs_exists (guestfs_h *handle,
This function returns a string, or NULL on error.
I<The caller must free the returned string after use>.
+=head2 guestfs_find
+
+ char **guestfs_find (guestfs_h *handle,
+ const char *directory);
+
+This command lists out all files and directories, recursively,
+starting at C<directory>. It is essentially equivalent to
+running the shell command C<find directory -print> but some
+post-processing happens on the output, described below.
+
+This returns a list of strings I<without any prefix>. Thus
+if the directory structure was:
+
+ /tmp/a
+ /tmp/b
+ /tmp/c/d
+
+then the returned list from C<guestfs_find> C</tmp> would be
+4 elements:
+
+ a
+ b
+ c
+ c/d
+
+If C<directory> is not a directory, then this command returns
+an error.
+
+The returned list is sorted.
+
+This function returns a NULL-terminated array of strings
+(like L<environ(3)>), or NULL if there was an error.
+I<The caller must free the strings and the array after use>.
+
+=head2 guestfs_fsck
+
+ int guestfs_fsck (guestfs_h *handle,
+ const char *fstype,
+ const char *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>.
+
+On error this function returns -1.
+
+=head2 guestfs_get_append
+
+ const char *guestfs_get_append (guestfs_h *handle);
+
+Return the additional kernel options which are added to the
+guest kernel command line.
+
+If C<NULL> then no options are added.
+
+This function returns a string, or NULL on error.
+The string is owned by the guest handle and must I<not> be freed.
+
=head2 guestfs_get_autosync
int guestfs_get_autosync (guestfs_h *handle);
This function returns a C truth value on success or -1 on error.
+=head2 guestfs_get_e2label
+
+ char *guestfs_get_e2label (guestfs_h *handle,
+ const char *device);
+
+This returns the ext2/3/4 filesystem label of the filesystem on
+C<device>.
+
+This function returns a string, or NULL on error.
+I<The caller must free the returned string after use>.
+
+=head2 guestfs_get_e2uuid
+
+ char *guestfs_get_e2uuid (guestfs_h *handle,
+ const char *device);
+
+This returns the ext2/3/4 filesystem UUID of the filesystem on
+C<device>.
+
+This function returns a string, or NULL on error.
+I<The caller must free the returned string after use>.
+
=head2 guestfs_get_path
const char *guestfs_get_path (guestfs_h *handle);
This function returns a string, or NULL on error.
The string is owned by the guest handle and must I<not> be freed.
+=head2 guestfs_get_qemu
+
+ const char *guestfs_get_qemu (guestfs_h *handle);
+
+Return the current qemu binary.
+
+This is always non-NULL. If it wasn't set already, then this will
+return the default qemu binary name.
+
+This function returns a string, or NULL on error.
+The string is owned by the guest handle and must I<not> be freed.
+
=head2 guestfs_get_state
int guestfs_get_state (guestfs_h *handle);
This function returns a C truth value on success or -1 on error.
+=head2 guestfs_grub_install
+
+ int guestfs_grub_install (guestfs_h *handle,
+ const char *root,
+ const char *device);
+
+This command installs GRUB (the Grand Unified Bootloader) on
+C<device>, with the root directory being C<root>.
+
+This function returns 0 on success or -1 on error.
+
+=head2 guestfs_hexdump
+
+ char *guestfs_hexdump (guestfs_h *handle,
+ const char *path);
+
+This runs C<hexdump -C> on the given C<path>. The result is
+the human-readable, canonical hex dump of the file.
+
+This function returns a string, or NULL on error.
+I<The caller must free the returned string after use>.
+
+Because of the message protocol, there is a transfer limit
+of somewhere between 2MB and 4MB. To transfer large files you should use
+FTP.
+
=head2 guestfs_is_busy
int guestfs_is_busy (guestfs_h *handle);
B<This command is dangerous. Without careful use you
can easily destroy all your data>.
+=head2 guestfs_lvremove
+
+ int guestfs_lvremove (guestfs_h *handle,
+ const char *device);
+
+Remove an LVM logical volume C<device>, where C<device> is
+the path to the LV, such as C</dev/VG/LV>.
+
+You can also remove all LVs in a volume group by specifying
+the VG name, C</dev/VG>.
+
+This function returns 0 on success or -1 on error.
+
+=head2 guestfs_lvresize
+
+ int guestfs_lvresize (guestfs_h *handle,
+ const char *device,
+ int mbytes);
+
+This resizes (expands or shrinks) an existing LVM logical
+volume to C<mbytes>. When reducing, data in the reduced part
+is lost.
+
+This function returns 0 on success or -1 on error.
+
=head2 guestfs_lvs
char **guestfs_lvs (guestfs_h *handle);
const char *device);
This creates a filesystem on C<device> (usually a partition
-of LVM logical volume). The filesystem type is C<fstype>, for
+or LVM logical volume). The filesystem type is C<fstype>, for
example C<ext3>.
This function returns 0 on success or -1 on error.
This function returns 0 on success or -1 on error.
+=head2 guestfs_mount_options
+
+ int guestfs_mount_options (guestfs_h *handle,
+ const char *options,
+ const char *device,
+ const char *mountpoint);
+
+This is the same as the C<guestfs_mount> command, but it
+allows you to set the mount options as for the
+L<mount(8)> I<-o> flag.
+
+This function returns 0 on success or -1 on error.
+
+=head2 guestfs_mount_ro
+
+ int guestfs_mount_ro (guestfs_h *handle,
+ const char *device,
+ const char *mountpoint);
+
+This is the same as the C<guestfs_mount> command, but it
+mounts the filesystem with the read-only (I<-o ro>) flag.
+
+This function returns 0 on success or -1 on error.
+
+=head2 guestfs_mount_vfs
+
+ int guestfs_mount_vfs (guestfs_h *handle,
+ const char *options,
+ const char *vfstype,
+ const char *device,
+ const char *mountpoint);
+
+This is the same as the C<guestfs_mount> command, but it
+allows you to set both the mount options and the vfstype
+as for the L<mount(8)> I<-o> and I<-t> flags.
+
+This function returns 0 on success or -1 on error.
+
=head2 guestfs_mounts
char **guestfs_mounts (guestfs_h *handle);
(like L<environ(3)>), or NULL if there was an error.
I<The caller must free the strings and the array after use>.
+=head2 guestfs_mv
+
+ int guestfs_mv (guestfs_h *handle,
+ const char *src,
+ const char *dest);
+
+This moves a file from C<src> to C<dest> where C<dest> is
+either a destination filename or destination directory.
+
+This function returns 0 on success or -1 on error.
+
+=head2 guestfs_ping_daemon
+
+ int guestfs_ping_daemon (guestfs_h *handle);
+
+This is a test probe into the guestfs daemon running inside
+the qemu subprocess. Calling this function checks that the
+daemon responds to the ping message, without affecting the daemon
+or attached block device(s) in any other way.
+
+This function returns 0 on success or -1 on error.
+
=head2 guestfs_pvcreate
int guestfs_pvcreate (guestfs_h *handle,
This function returns 0 on success or -1 on error.
+=head2 guestfs_pvremove
+
+ int guestfs_pvremove (guestfs_h *handle,
+ const char *device);
+
+This wipes a physical volume C<device> so that LVM will no longer
+recognise it.
+
+The implementation uses the C<pvremove> command which refuses to
+wipe physical volumes that contain any volume groups, so you have
+to remove those first.
+
+This function returns 0 on success or -1 on error.
+
+=head2 guestfs_pvresize
+
+ int guestfs_pvresize (guestfs_h *handle,
+ const char *device);
+
+This resizes (expands or shrinks) an existing LVM physical
+volume to match the new size of the underlying device.
+
+This function returns 0 on success or -1 on error.
+
=head2 guestfs_pvs
char **guestfs_pvs (guestfs_h *handle);
(like L<environ(3)>), or NULL if there was an error.
I<The caller must free the strings and the array after use>.
+=head2 guestfs_resize2fs
+
+ int guestfs_resize2fs (guestfs_h *handle,
+ const char *device);
+
+This resizes an ext2 or ext3 filesystem to match the size of
+the underlying device.
+
+I<Note:> It is sometimes required that you run C<guestfs_e2fsck_f>
+on the C<device> before calling this command. For unknown reasons
+C<resize2fs> sometimes gives an error about this and sometimes not.
+In any case, it is always safe to call C<guestfs_e2fsck_f> before
+calling this function.
+
+This function returns 0 on success or -1 on error.
+
=head2 guestfs_rm
int guestfs_rm (guestfs_h *handle,
This function returns 0 on success or -1 on error.
+=head2 guestfs_set_append
+
+ int guestfs_set_append (guestfs_h *handle,
+ const char *append);
+
+This function is used to add additional options to the
+guest kernel command line.
+
+The default is C<NULL> unless overridden by setting
+C<LIBGUESTFS_APPEND> environment variable.
+
+Setting C<append> to C<NULL> means I<no> additional options
+are passed (libguestfs always adds a few of its own).
+
+This function returns 0 on success or -1 on error.
+
=head2 guestfs_set_autosync
int guestfs_set_autosync (guestfs_h *handle,
int autosync);
If C<autosync> is true, this enables autosync. Libguestfs will make a
-best effort attempt to run C<guestfs_sync> when the handle is closed
+best effort attempt to run C<guestfs_umount_all> followed by
+C<guestfs_sync> when the handle is closed
(also if the program exits without closing handles).
+This is disabled by default (except in guestfish where it is
+enabled by default).
+
This function returns 0 on success or -1 on error.
=head2 guestfs_set_busy
This function returns 0 on success or -1 on error.
+=head2 guestfs_set_e2label
+
+ int guestfs_set_e2label (guestfs_h *handle,
+ const char *device,
+ const char *label);
+
+This sets the ext2/3/4 filesystem label of the filesystem on
+C<device> to C<label>. Filesystem labels are limited to
+16 characters.
+
+You can use either C<guestfs_tune2fs_l> or C<guestfs_get_e2label>
+to return the existing label on a filesystem.
+
+This function returns 0 on success or -1 on error.
+
+=head2 guestfs_set_e2uuid
+
+ int guestfs_set_e2uuid (guestfs_h *handle,
+ const char *device,
+ const char *uuid);
+
+This sets the ext2/3/4 filesystem UUID of the filesystem on
+C<device> to C<uuid>. The format of the UUID and alternatives
+such as C<clear>, C<random> and C<time> are described in the
+L<tune2fs(8)> manpage.
+
+You can use either C<guestfs_tune2fs_l> or C<guestfs_get_e2uuid>
+to return the existing UUID of a filesystem.
+
+This function returns 0 on success or -1 on error.
+
=head2 guestfs_set_path
int guestfs_set_path (guestfs_h *handle,
The default is C<$libdir/guestfs> unless overridden by setting
C<LIBGUESTFS_PATH> environment variable.
-The string C<path> is stashed in the libguestfs handle, so the caller
-must make sure it remains valid for the lifetime of the handle.
-
Setting C<path> to C<NULL> restores the default path.
This function returns 0 on success or -1 on error.
+=head2 guestfs_set_qemu
+
+ int guestfs_set_qemu (guestfs_h *handle,
+ const char *qemu);
+
+Set the qemu binary that we will use.
+
+The default is chosen when the library was compiled by the
+configure script.
+
+You can also override this by setting the C<LIBGUESTFS_QEMU>
+environment variable.
+
+Setting C<qemu> to C<NULL> restores the default qemu binary.
+
+This function returns 0 on success or -1 on error.
+
=head2 guestfs_set_ready
int guestfs_set_ready (guestfs_h *handle);
pass C<lines> as a single element list, when the single element being
the string C<,> (comma).
+See also: C<guestfs_sfdisk_l>, C<guestfs_sfdisk_N>
+
This function returns 0 on success or -1 on error.
B<This command is dangerous. Without careful use you
can easily destroy all your data>.
+=head2 guestfs_sfdisk_N
+
+ int guestfs_sfdisk_N (guestfs_h *handle,
+ const char *device,
+ int n,
+ int cyls,
+ int heads,
+ int sectors,
+ const char *line);
+
+This runs L<sfdisk(8)> option to modify just the single
+partition C<n> (note: C<n> counts from 1).
+
+For other parameters, see C<guestfs_sfdisk>. You should usually
+pass C<0> for the cyls/heads/sectors parameters.
+
+This function returns 0 on success or -1 on error.
+
+B<This command is dangerous. Without careful use you
+can easily destroy all your data>.
+
+=head2 guestfs_sfdisk_disk_geometry
+
+ char *guestfs_sfdisk_disk_geometry (guestfs_h *handle,
+ const char *device);
+
+This displays the disk geometry of C<device> read from the
+partition table. Especially in the case where the underlying
+block device has been resized, this can be different from the
+kernel's idea of the geometry (see C<guestfs_sfdisk_kernel_geometry>).
+
+The result is in human-readable format, and not designed to
+be parsed.
+
+This function returns a string, or NULL on error.
+I<The caller must free the returned string after use>.
+
+=head2 guestfs_sfdisk_kernel_geometry
+
+ char *guestfs_sfdisk_kernel_geometry (guestfs_h *handle,
+ const char *device);
+
+This displays the kernel's idea of the geometry of C<device>.
+
+The result is in human-readable format, and not designed to
+be parsed.
+
+This function returns a string, or NULL on error.
+I<The caller must free the returned string after use>.
+
+=head2 guestfs_sfdisk_l
+
+ char *guestfs_sfdisk_l (guestfs_h *handle,
+ const char *device);
+
+This displays the partition table on C<device>, in the
+human-readable output of the L<sfdisk(8)> command. It is
+not intended to be parsed.
+
+This function returns a string, or NULL on error.
+I<The caller must free the returned string after use>.
+
=head2 guestfs_stat
struct guestfs_stat *guestfs_stat (guestfs_h *handle,
or NULL if there was an error.
I<The caller must call C<free> after use>.
+=head2 guestfs_strings
+
+ char **guestfs_strings (guestfs_h *handle,
+ const char *path);
+
+This runs the L<strings(1)> command on a file and returns
+the list of printable strings found.
+
+This function returns a NULL-terminated array of strings
+(like L<environ(3)>), or NULL if there was an error.
+I<The caller must free the strings and the array after use>.
+
+Because of the message protocol, there is a transfer limit
+of somewhere between 2MB and 4MB. To transfer large files you should use
+FTP.
+
+=head2 guestfs_strings_e
+
+ char **guestfs_strings_e (guestfs_h *handle,
+ const char *encoding,
+ const char *path);
+
+This is like the C<guestfs_strings> command, but allows you to
+specify the encoding.
+
+See the L<strings(1)> manpage for the full list of encodings.
+
+Commonly useful encodings are C<l> (lower case L) which will
+show strings inside Windows/x86 files.
+
+The returned strings are transcoded to UTF-8.
+
+This function returns a NULL-terminated array of strings
+(like L<environ(3)>), or NULL if there was an error.
+I<The caller must free the strings and the array after use>.
+
+Because of the message protocol, there is a transfer limit
+of somewhere between 2MB and 4MB. To transfer large files you should use
+FTP.
+
=head2 guestfs_sync
int guestfs_sync (guestfs_h *handle);
This function returns 0 on success or -1 on error.
+=head2 guestfs_tar_in
+
+ int guestfs_tar_in (guestfs_h *handle,
+ const char *tarfile,
+ const char *directory);
+
+This command uploads and unpacks local file C<tarfile> (an
+I<uncompressed> tar file) into C<directory>.
+
+To upload a compressed tarball, use C<guestfs_tgz_in>.
+
+This function returns 0 on success or -1 on error.
+
+=head2 guestfs_tar_out
+
+ int guestfs_tar_out (guestfs_h *handle,
+ const char *directory,
+ const char *tarfile);
+
+This command packs the contents of C<directory> and downloads
+it to local file C<tarfile>.
+
+To download a compressed tarball, use C<guestfs_tgz_out>.
+
+This function returns 0 on success or -1 on error.
+
+=head2 guestfs_tgz_in
+
+ int guestfs_tgz_in (guestfs_h *handle,
+ const char *tarball,
+ const char *directory);
+
+This command uploads and unpacks local file C<tarball> (a
+I<gzip compressed> tar file) into C<directory>.
+
+To upload an uncompressed tarball, use C<guestfs_tar_in>.
+
+This function returns 0 on success or -1 on error.
+
+=head2 guestfs_tgz_out
+
+ int guestfs_tgz_out (guestfs_h *handle,
+ const char *directory,
+ const char *tarball);
+
+This command packs the contents of C<directory> and downloads
+it to local file C<tarball>.
+
+To download an uncompressed tarball, use C<guestfs_tar_out>.
+
+This function returns 0 on success or -1 on error.
+
=head2 guestfs_touch
int guestfs_touch (guestfs_h *handle,
char **guestfs_tune2fs_l (guestfs_h *handle,
const char *device);
-This returns the contents of the ext2 or ext3 filesystem superblock
-on C<device>.
+This returns the contents of the ext2, ext3 or ext4 filesystem
+superblock on C<device>.
It is the same as running C<tune2fs -l device>. See L<tune2fs(8)>
manpage for more details. The list of fields returned isn't
This function returns 0 on success or -1 on error.
+=head2 guestfs_vg_activate
+
+ int guestfs_vg_activate (guestfs_h *handle,
+ int activate,
+ char * const* const volgroups);
+
+This command activates or (if C<activate> is false) deactivates
+all logical volumes in the listed volume groups C<volgroups>.
+If activated, then they are made known to the
+kernel, ie. they appear as C</dev/mapper> devices. If deactivated,
+then those devices disappear.
+
+This command is the same as running C<vgchange -a y|n volgroups...>
+
+Note that if C<volgroups> is an empty list then B<all> volume groups
+are activated or deactivated.
+
+This function returns 0 on success or -1 on error.
+
+=head2 guestfs_vg_activate_all
+
+ int guestfs_vg_activate_all (guestfs_h *handle,
+ int activate);
+
+This command activates or (if C<activate> is false) deactivates
+all logical volumes in all volume groups.
+If activated, then they are made known to the
+kernel, ie. they appear as C</dev/mapper> devices. If deactivated,
+then those devices disappear.
+
+This command is the same as running C<vgchange -a y|n>
+
+This function returns 0 on success or -1 on error.
+
=head2 guestfs_vgcreate
int guestfs_vgcreate (guestfs_h *handle,
This function returns 0 on success or -1 on error.
+=head2 guestfs_vgremove
+
+ int guestfs_vgremove (guestfs_h *handle,
+ const char *vgname);
+
+Remove an LVM volume group C<vgname>, (for example C<VG>).
+
+This also forcibly removes all logical volumes in the volume
+group (if any).
+
+This function returns 0 on success or -1 on error.
+
=head2 guestfs_vgs
char **guestfs_vgs (guestfs_h *handle);
then the length is calculated using C<strlen> (so in this case
the content cannot contain embedded ASCII NULs).
+I<NB.> Owing to a bug, writing content containing ASCII NUL
+characters does I<not> work, even if the length is specified.
+We hope to resolve this bug in a future version. In the meantime
+use C<guestfs_upload>.
+
This function returns 0 on success or -1 on error.
Because of the message protocol, there is a transfer limit
of somewhere between 2MB and 4MB. To transfer large files you should use
FTP.
+=head2 guestfs_zero
+
+ int guestfs_zero (guestfs_h *handle,
+ const char *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.
+
+This function returns 0 on success or -1 on error.
+
+=head2 guestfs_zerofree
+
+ int guestfs_zerofree (guestfs_h *handle,
+ const char *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.
+
+This function returns 0 on success or -1 on error.
+