Sys::Guestfs(3) User Contributed Perl Documentation Sys::Guestfs(3)NAMESys::Guestfs - Perl bindings for libguestfs
SYNOPSIS
use Sys::Guestfs;
my $g = Sys::Guestfs->new ();
$g->add_drive_opts ('guest.img', format => 'raw');
$g->launch ();
$g->mount ('/dev/sda1', '/');
$g->touch ('/hello');
$g->shutdown ();
$g->close ();
DESCRIPTION
The "Sys::Guestfs" module provides a Perl XS binding to the libguestfs
API for examining and modifying virtual machine disk images.
Amongst the things this is good for: making batch configuration changes
to guests, getting disk used/free statistics (see also: virt-df),
migrating between virtualization systems (see also: virt-p2v),
performing partial backups, performing partial guest clones, cloning
guests and changing registry/UUID/hostname info, and much else besides.
Libguestfs uses Linux kernel and qemu code, and can access any type of
guest filesystem that Linux and qemu can, including but not limited to:
ext2/3/4, btrfs, FAT and NTFS, LVM, many different disk partition
schemes, qcow, qcow2, vmdk.
Libguestfs provides ways to enumerate guest storage (eg. partitions,
LVs, what filesystem is in each LV, etc.). It can also run commands in
the context of the guest. Also you can access filesystems over FUSE.
ERRORS
All errors turn into calls to "croak" (see Carp(3)).
The error string from libguestfs is directly available from $@. Use
the "last_errno" method if you want to get the errno.
METHODS
$g = Sys::Guestfs->new ([environment => 0,] [close_on_exit => 0]);
Create a new guestfs handle.
If the optional argument "environment" is false, then the
"GUESTFS_CREATE_NO_ENVIRONMENT" flag is set.
If the optional argument "close_on_exit" is false, then the
"GUESTFS_CREATE_NO_CLOSE_ON_EXIT" flag is set.
$g->close ();
Explicitly close the guestfs handle.
Note: You should not usually call this function. The handle will
be closed implicitly when its reference count goes to zero (eg.
when it goes out of scope or the program ends). This call is only
required in some exceptional cases, such as where the program may
contain cached references to the handle 'somewhere' and you really
have to have the close happen right away. After calling "close"
the program must not call any method (including "close") on the
handle (but the implicit call to "DESTROY" that happens when the
final reference is cleaned up is OK).
$Sys::Guestfs::EVENT_CLOSE
See "GUESTFS_EVENT_CLOSE" in guestfs(3).
$Sys::Guestfs::EVENT_SUBPROCESS_QUIT
See "GUESTFS_EVENT_SUBPROCESS_QUIT" in guestfs(3).
$Sys::Guestfs::EVENT_LAUNCH_DONE
See "GUESTFS_EVENT_LAUNCH_DONE" in guestfs(3).
$Sys::Guestfs::EVENT_PROGRESS
See "GUESTFS_EVENT_PROGRESS" in guestfs(3).
$Sys::Guestfs::EVENT_APPLIANCE
See "GUESTFS_EVENT_APPLIANCE" in guestfs(3).
$Sys::Guestfs::EVENT_LIBRARY
See "GUESTFS_EVENT_LIBRARY" in guestfs(3).
$Sys::Guestfs::EVENT_TRACE
See "GUESTFS_EVENT_TRACE" in guestfs(3).
$Sys::Guestfs::EVENT_ENTER
See "GUESTFS_EVENT_ENTER" in guestfs(3).
$Sys::Guestfs::EVENT_LIBVIRT_AUTH
See "GUESTFS_EVENT_LIBVIRT_AUTH" in guestfs(3).
$Sys::Guestfs::EVENT_ALL
See "GUESTFS_EVENT_ALL" in guestfs(3).
$event_handle = $g->set_event_callback (\&cb, $event_bitmask);
Register "cb" as a callback function for all of the events in
$event_bitmask (one or more "$Sys::Guestfs::EVENT_*" flags
logically or'd together).
This function returns an event handle which can be used to delete
the callback using "delete_event_callback".
The callback function receives 4 parameters:
&cb ($event, $event_handle, $buf, $array)
$event
The event which happened (equal to one of
"$Sys::Guestfs::EVENT_*").
$event_handle
The event handle.
$buf
For some event types, this is a message buffer (ie. a string).
$array
For some event types (notably progress events), this is an
array of integers.
You should carefully read the documentation for
"guestfs_set_event_callback" in guestfs(3) before using this
function.
$g->delete_event_callback ($event_handle);
This removes the callback which was previously registered using
"set_event_callback".
$str = Sys::Guestfs::event_to_string ($events);
$events is either a single event or a bitmask of events. This
returns a printable string, useful for debugging.
Note that this is a class function, not a method.
$errnum = $g->last_errno ();
This returns the last error number (errno) that happened on the
handle $g.
If successful, an errno integer not equal to zero is returned.
If no error number is available, this returns 0. See
"guestfs_last_errno" in guestfs(3) for more details of why this can
happen.
You can use the standard Perl module Errno(3) to compare the
numeric error returned from this call with symbolic errnos:
$g->mkdir ("/foo");
if ($g->last_errno() == Errno::EEXIST()) {
# mkdir failed because the directory exists already.
}
$g->acl_delete_def_file ($dir);
This function deletes the default POSIX Access Control List (ACL)
attached to directory "dir".
$acl = $g->acl_get_file ($path, $acltype);
This function returns the POSIX Access Control List (ACL) attached
to "path". The ACL is returned in "long text form" (see acl(5)).
The "acltype" parameter may be:
"access"
Return the ordinary (access) ACL for any file, directory or
other filesystem object.
"default"
Return the default ACL. Normally this only makes sense if
"path" is a directory.
$g->acl_set_file ($path, $acltype, $acl);
This function sets the POSIX Access Control List (ACL) attached to
"path".
The "acltype" parameter may be:
"access"
Set the ordinary (access) ACL for any file, directory or other
filesystem object.
"default"
Set the default ACL. Normally this only makes sense if "path"
is a directory.
The "acl" parameter is the new ACL in either "long text form" or
"short text form" (see acl(5)). The new ACL completely replaces
any previous ACL on the file. The ACL must contain the full Unix
permissions (eg. "u::rwx,g::rx,o::rx").
If you are specifying individual users or groups, then the mask
field is also required (eg. "m::rwx"), followed by the "u:ID:..."
and/or "g:ID:..." field(s). A full ACL string might therefore look
like this:
u::rwx,g::rwx,o::rwx,m::rwx,u:500:rwx,g:500:rwx
\ Unix permissions / \mask/ \ ACL /
You should use numeric UIDs and GIDs. To map usernames and
groupnames to the correct numeric ID in the context of the guest,
use the Augeas functions (see "$g->aug_init").
$g->add_cdrom ($filename);
This function adds a virtual CD-ROM disk image to the guest.
Do not use this function! ISO files are just ordinary read-only
disk images. Use "$g->add_drive_ro" instead.
This function is deprecated. In new code, use the "add_drive" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$nrdisks = $g->add_domain ($dom [, libvirturi => $libvirturi] [,
readonly => $readonly] [, iface => $iface] [, live => $live] [,
allowuuid => $allowuuid] [, readonlydisk => $readonlydisk]);
This function adds the disk(s) attached to the named libvirt domain
"dom". It works by connecting to libvirt, requesting the domain
and domain XML from libvirt, parsing it for disks, and calling
"$g->add_drive_opts" on each one.
The number of disks added is returned. This operation is atomic:
if an error is returned, then no disks are added.
This function does some minimal checks to make sure the libvirt
domain is not running (unless "readonly" is true). In a future
version we will try to acquire the libvirt lock on each disk.
Disks must be accessible locally. This often means that adding
disks from a remote libvirt connection (see
<http://libvirt.org/remote.html>) will fail unless those disks are
accessible via the same device path locally too.
The optional "libvirturi" parameter sets the libvirt URI (see
<http://libvirt.org/uri.html>). If this is not set then we connect
to the default libvirt URI (or one set through an environment
variable, see the libvirt documentation for full details).
The optional "live" flag controls whether this call will try to
connect to a running virtual machine "guestfsd" process if it sees
a suitable <channel> element in the libvirt XML definition. The
default (if the flag is omitted) is never to try. See "ATTACHING
TO RUNNING DAEMONS" in guestfs(3) for more information.
If the "allowuuid" flag is true (default is false) then a UUID may
be passed instead of the domain name. The "dom" string is treated
as a UUID first and looked up, and if that lookup fails then we
treat "dom" as a name as usual.
The optional "readonlydisk" parameter controls what we do for disks
which are marked <readonly/> in the libvirt XML. Possible values
are:
readonlydisk = "error"
If "readonly" is false:
The whole call is aborted with an error if any disk with the
<readonly/> flag is found.
If "readonly" is true:
Disks with the <readonly/> flag are added read-only.
readonlydisk = "read"
If "readonly" is false:
Disks with the <readonly/> flag are added read-only. Other
disks are added read/write.
If "readonly" is true:
Disks with the <readonly/> flag are added read-only.
readonlydisk = "write" (default)
If "readonly" is false:
Disks with the <readonly/> flag are added read/write.
If "readonly" is true:
Disks with the <readonly/> flag are added read-only.
readonlydisk = "ignore"
If "readonly" is true or false:
Disks with the <readonly/> flag are skipped.
The other optional parameters are passed directly through to
"$g->add_drive_opts".
$g->add_drive ($filename [, readonly => $readonly] [, format =>
$format] [, iface => $iface] [, name => $name] [, label => $label] [,
protocol => $protocol] [, server => $server] [, username => $username]
[, secret => $secret] [, cachemode => $cachemode]);
This function adds a disk image called "filename" to the handle.
"filename" may be a regular host file or a host device.
When this function is called before "$g->launch" (the usual case)
then the first time you call this function, the disk appears in the
API as "/dev/sda", the second time as "/dev/sdb", and so on.
In libguestfs X 1.20 you can also call this function after launch
(with some restrictions). This is called "hotplugging". When
hotplugging, you must specify a "label" so that the new disk gets a
predictable name. For more information see "HOTPLUGGING" in
guestfs(3).
You don't necessarily need to be root when using libguestfs.
However you obviously do need sufficient permissions to access the
filename for whatever operations you want to perform (ie. read
access if you just want to read the image or write access if you
want to modify the image).
This call checks that "filename" exists.
"filename" may be the special string "/dev/null". See "NULL DISKS"
in guestfs(3).
The optional arguments are:
"readonly"
If true then the image is treated as read-only. Writes are
still allowed, but they are stored in a temporary snapshot
overlay which is discarded at the end. The disk that you add
is not modified.
"format"
This forces the image format. If you omit this (or use
"$g->add_drive" or "$g->add_drive_ro") then the format is
automatically detected. Possible formats include "raw" and
"qcow2".
Automatic detection of the format opens you up to a potential
security hole when dealing with untrusted raw-format images.
See CVE-2010-3851 and RHBZ#642934. Specifying the format
closes this security hole.
"iface"
This rarely-used option lets you emulate the behaviour of the
deprecated "$g->add_drive_with_if" call (q.v.)
"name"
The name the drive had in the original guest, e.g. "/dev/sdb".
This is used as a hint to the guest inspection process if it is
available.
"label"
Give the disk a label. The label should be a unique, short
string using only ASCII characters "[a-zA-Z]". As well as its
usual name in the API (such as "/dev/sda"), the drive will also
be named "/dev/disk/guestfs/label".
See "DISK LABELS" in guestfs(3).
"protocol"
The optional protocol argument can be used to select an
alternate source protocol.
See also: "REMOTE STORAGE" in guestfs(3).
"protocol = "file""
"filename" is interpreted as a local file or device. This
is the default if the optional protocol parameter is
omitted.
"protocol = "nbd""
Connect to the Network Block Device server. The "server"
parameter must also be supplied - see below.
See also: "NETWORK BLOCK DEVICE" in guestfs(3).
"server"
For protocols which require access to a remote server, this is
a list of server(s).
Protocol Number of servers required
----------------------------------
file List must be empty or param not used at all
nbd Exactly one
Each list element is a string specifying a server. The string
must be in one of the following formats:
hostname
hostname:port
tcp:hostname
tcp:hostname:port
unix:/path/to/socket
If the port number is omitted, then the standard port number
for the protocol is used (see "/etc/services").
"cachemode"
Choose whether or not libguestfs will obey sync operations
(safe but slow) or not (unsafe but fast). The possible values
for this string are:
"cachemode = "writeback""
This is the default.
Write operations in the API do not return until a write(2)
call has completed in the host [but note this does not
imply that anything gets written to disk].
Sync operations in the API, including implicit syncs caused
by filesystem journalling, will not return until an
fdatasync(2) call has completed in the host, indicating
that data has been committed to disk.
"cachemode = "unsafe""
In this mode, there are no guarantees. Libguestfs may
cache anything and ignore sync requests. This is suitable
only for scratch or temporary disks.
$g->add_drive_opts ($filename [, readonly => $readonly] [, format =>
$format] [, iface => $iface] [, name => $name] [, label => $label] [,
protocol => $protocol] [, server => $server] [, username => $username]
[, secret => $secret] [, cachemode => $cachemode]);
This is an alias of "add_drive".
$g->add_drive_ro ($filename);
This function is the equivalent of calling "$g->add_drive_opts"
with the optional parameter "GUESTFS_ADD_DRIVE_OPTS_READONLY" set
to 1, so the disk is added read-only, with the format being
detected automatically.
$g->add_drive_ro_with_if ($filename, $iface);
This is the same as "$g->add_drive_ro" but it allows you to specify
the QEMU interface emulation to use at run time.
This function is deprecated. In new code, use the "add_drive" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->add_drive_scratch ($size [, name => $name] [, label => $label]);
This command adds a temporary scratch drive to the handle. The
"size" parameter is the virtual size (in bytes). The scratch drive
is blank initially (all reads return zeroes until you start writing
to it). The drive is deleted when the handle is closed.
The optional arguments "name" and "label" are passed through to
"$g->add_drive".
$g->add_drive_with_if ($filename, $iface);
This is the same as "$g->add_drive" but it allows you to specify
the QEMU interface emulation to use at run time.
This function is deprecated. In new code, use the "add_drive" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->aug_clear ($augpath);
Set the value associated with "path" to "NULL". This is the same
as the augtool(1) "clear" command.
$g->aug_close ();
Close the current Augeas handle and free up any resources used by
it. After calling this, you have to call "$g->aug_init" again
before you can use any other Augeas functions.
%nrnodescreated = $g->aug_defnode ($name, $expr, $val);
Defines a variable "name" whose value is the result of evaluating
"expr".
If "expr" evaluates to an empty nodeset, a node is created,
equivalent to calling "$g->aug_set" "expr", "value". "name" will
be the nodeset containing that single node.
On success this returns a pair containing the number of nodes in
the nodeset, and a boolean flag if a node was created.
$nrnodes = $g->aug_defvar ($name, $expr);
Defines an Augeas variable "name" whose value is the result of
evaluating "expr". If "expr" is NULL, then "name" is undefined.
On success this returns the number of nodes in "expr", or 0 if
"expr" evaluates to something which is not a nodeset.
$val = $g->aug_get ($augpath);
Look up the value associated with "path". If "path" matches
exactly one node, the "value" is returned.
$g->aug_init ($root, $flags);
Create a new Augeas handle for editing configuration files. If
there was any previous Augeas handle associated with this guestfs
session, then it is closed.
You must call this before using any other "$g->aug_*" commands.
"root" is the filesystem root. "root" must not be NULL, use "/"
instead.
The flags are the same as the flags defined in <augeas.h>, the
logical or of the following integers:
"AUG_SAVE_BACKUP" = 1
Keep the original file with a ".augsave" extension.
"AUG_SAVE_NEWFILE" = 2
Save changes into a file with extension ".augnew", and do not
overwrite original. Overrides "AUG_SAVE_BACKUP".
"AUG_TYPE_CHECK" = 4
Typecheck lenses.
This option is only useful when debugging Augeas lenses. Use
of this option may require additional memory for the libguestfs
appliance. You may need to set the "LIBGUESTFS_MEMSIZE"
environment variable or call "$g->set_memsize".
"AUG_NO_STDINC" = 8
Do not use standard load path for modules.
"AUG_SAVE_NOOP" = 16
Make save a no-op, just record what would have been changed.
"AUG_NO_LOAD" = 32
Do not load the tree in "$g->aug_init".
To close the handle, you can call "$g->aug_close".
To find out more about Augeas, see <http://augeas.net/>.
$g->aug_insert ($augpath, $label, $before);
Create a new sibling "label" for "path", inserting it into the tree
before or after "path" (depending on the boolean flag "before").
"path" must match exactly one existing node in the tree, and
"label" must be a label, ie. not contain "/", "*" or end with a
bracketed index "[N]".
$g->aug_load ();
Load files into the tree.
See "aug_load" in the Augeas documentation for the full gory
details.
@matches = $g->aug_ls ($augpath);
This is just a shortcut for listing "$g->aug_match" "path/*" and
sorting the resulting nodes into alphabetical order.
@matches = $g->aug_match ($augpath);
Returns a list of paths which match the path expression "path".
The returned paths are sufficiently qualified so that they match
exactly one node in the current tree.
$g->aug_mv ($src, $dest);
Move the node "src" to "dest". "src" must match exactly one node.
"dest" is overwritten if it exists.
$nrnodes = $g->aug_rm ($augpath);
Remove "path" and all of its children.
On success this returns the number of entries which were removed.
$g->aug_save ();
This writes all pending changes to disk.
The flags which were passed to "$g->aug_init" affect exactly how
files are saved.
$g->aug_set ($augpath, $val);
Set the value associated with "path" to "val".
In the Augeas API, it is possible to clear a node by setting the
value to NULL. Due to an oversight in the libguestfs API you
cannot do that with this call. Instead you must use the
"$g->aug_clear" call.
$g->available (\@groups);
This command is used to check the availability of some groups of
functionality in the appliance, which not all builds of the
libguestfs appliance will be able to provide.
The libguestfs groups, and the functions that those groups
correspond to, are listed in "AVAILABILITY" in guestfs(3). You can
also fetch this list at runtime by calling
"$g->available_all_groups".
The argument "groups" is a list of group names, eg: "["inotify",
"augeas"]" would check for the availability of the Linux inotify
functions and Augeas (configuration file editing) functions.
The command returns no error if all requested groups are available.
It fails with an error if one or more of the requested groups is
unavailable in the appliance.
If an unknown group name is included in the list of groups then an
error is always returned.
Notes:
· "$g->feature_available" is the same as this call, but with a
slightly simpler to use API: that call returns a boolean
true/false instead of throwing an error.
· You must call "$g->launch" before calling this function.
The reason is because we don't know what groups are supported
by the appliance/daemon until it is running and can be queried.
· If a group of functions is available, this does not necessarily
mean that they will work. You still have to check for errors
when calling individual API functions even if they are
available.
· It is usually the job of distro packagers to build complete
functionality into the libguestfs appliance. Upstream
libguestfs, if built from source with all requirements
satisfied, will support everything.
· This call was added in version 1.0.80. In previous versions of
libguestfs all you could do would be to speculatively execute a
command to find out if the daemon implemented it. See also
"$g->version".
See also "$g->filesystem_available".
@groups = $g->available_all_groups ();
This command returns a list of all optional groups that this daemon
knows about. Note this returns both supported and unsupported
groups. To find out which ones the daemon can actually support you
have to call "$g->available" / "$g->feature_available" on each
member of the returned list.
See also "$g->available", "$g->feature_available" and
"AVAILABILITY" in guestfs(3).
$g->base64_in ($base64file, $filename);
This command uploads base64-encoded data from "base64file" to
"filename".
$g->base64_out ($filename, $base64file);
This command downloads the contents of "filename", writing it out
to local file "base64file" encoded as base64.
%info = $g->blkid ($device);
This command returns block device attributes for "device". The
following fields are usually present in the returned hash. Other
fields may also be present.
"UUID"
The uuid of this device.
"LABEL"
The label of this device.
"VERSION"
The version of blkid command.
"TYPE"
The filesystem type or RAID of this device.
"USAGE"
The usage of this device, for example "filesystem" or "raid".
$g->blockdev_flushbufs ($device);
This tells the kernel to flush internal buffers associated with
"device".
This uses the blockdev(8) command.
$blocksize = $g->blockdev_getbsz ($device);
This returns the block size of a device.
Note: this is different from both size in blocks and filesystem
block size. Also this setting is not really used by anything. You
should probably not use it for anything. Filesystems have their
own idea about what block size to choose.
This uses the blockdev(8) command.
$ro = $g->blockdev_getro ($device);
Returns a boolean indicating if the block device is read-only (true
if read-only, false if not).
This uses the blockdev(8) command.
$sizeinbytes = $g->blockdev_getsize64 ($device);
This returns the size of the device in bytes.
See also "$g->blockdev_getsz".
This uses the blockdev(8) command.
$sectorsize = $g->blockdev_getss ($device);
This returns the size of sectors on a block device. Usually 512,
but can be larger for modern devices.
(Note, this is not the size in sectors, use "$g->blockdev_getsz"
for that).
This uses the blockdev(8) command.
$sizeinsectors = $g->blockdev_getsz ($device);
This returns the size of the device in units of 512-byte sectors
(even if the sectorsize isn't 512 bytes ... weird).
See also "$g->blockdev_getss" for the real sector size of the
device, and "$g->blockdev_getsize64" for the more useful size in
bytes.
This uses the blockdev(8) command.
$g->blockdev_rereadpt ($device);
Reread the partition table on "device".
This uses the blockdev(8) command.
$g->blockdev_setbsz ($device, $blocksize);
This call does nothing and has never done anything because of a bug
in blockdev. Do not use it.
If you need to set the filesystem block size, use the "blocksize"
option of "$g->mkfs".
This function is deprecated. In new code, use the "mkfs" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->blockdev_setro ($device);
Sets the block device named "device" to read-only.
This uses the blockdev(8) command.
$g->blockdev_setrw ($device);
Sets the block device named "device" to read-write.
This uses the blockdev(8) command.
$g->btrfs_device_add (\@devices, $fs);
Add the list of device(s) in "devices" to the btrfs filesystem
mounted at "fs". If "devices" is an empty list, this does nothing.
$g->btrfs_device_delete (\@devices, $fs);
Remove the "devices" from the btrfs filesystem mounted at "fs". If
"devices" is an empty list, this does nothing.
$g->btrfs_filesystem_balance ($fs);
Balance the chunks in the btrfs filesystem mounted at "fs" across
the underlying devices.
$g->btrfs_filesystem_resize ($mountpoint [, size => $size]);
This command resizes a btrfs filesystem.
Note that unlike other resize calls, the filesystem has to be
mounted and the parameter is the mountpoint not the device (this is
a requirement of btrfs itself).
The optional parameters are:
"size"
The new size (in bytes) of the filesystem. If omitted, the
filesystem is resized to the maximum size.
See also btrfs(8).
$g->btrfs_filesystem_sync ($fs);
Force sync on the btrfs filesystem mounted at "fs".
$g->btrfs_fsck ($device [, superblock => $superblock] [, repair =>
$repair]);
Used to check a btrfs filesystem, "device" is the device file where
the filesystem is stored.
$g->btrfs_set_seeding ($device, $seeding);
Enable or disable the seeding feature of a device that contains a
btrfs filesystem.
$g->btrfs_subvolume_create ($dest);
Create a btrfs subvolume. The "dest" argument is the destination
directory and the name of the snapshot, in the form
"/path/to/dest/name".
$g->btrfs_subvolume_delete ($subvolume);
Delete the named btrfs subvolume.
@subvolumes = $g->btrfs_subvolume_list ($fs);
List the btrfs snapshots and subvolumes of the btrfs filesystem
which is mounted at "fs".
$g->btrfs_subvolume_set_default ($id, $fs);
Set the subvolume of the btrfs filesystem "fs" which will be
mounted by default. See "$g->btrfs_subvolume_list" to get a list
of subvolumes.
$g->btrfs_subvolume_snapshot ($source, $dest);
Create a writable snapshot of the btrfs subvolume "source". The
"dest" argument is the destination directory and the name of the
snapshot, in the form "/path/to/dest/name".
$canonical = $g->canonical_device_name ($device);
This utility function is useful when displaying device names to the
user. It takes a number of irregular device names and returns them
in a consistent format:
"/dev/hdX"
"/dev/vdX"
These are returned as "/dev/sdX". Note this works for device
names and partition names. This is approximately the reverse
of the algorithm described in "BLOCK DEVICE NAMING" in
guestfs(3).
"/dev/mapper/VG-LV"
"/dev/dm-N"
Converted to "/dev/VG/LV" form using
"$g->lvm_canonical_lvm_name".
Other strings are returned unmodified.
$cap = $g->cap_get_file ($path);
This function returns the Linux capabilities attached to "path".
The capabilities set is returned in text form (see cap_to_text(3)).
If no capabilities are attached to a file, an empty string is
returned.
$g->cap_set_file ($path, $cap);
This function sets the Linux capabilities attached to "path". The
capabilities set "cap" should be passed in text form (see
cap_from_text(3)).
$rpath = $g->case_sensitive_path ($path);
This can be used to resolve case insensitive paths on a filesystem
which is case sensitive. The use case is to resolve paths which
you have read from Windows configuration files or the Windows
Registry, to the true path.
The command handles a peculiarity of the Linux ntfs-3g filesystem
driver (and probably others), which is that although the underlying
filesystem is case-insensitive, the driver exports the filesystem
to Linux as case-sensitive.
One consequence of this is that special directories such as
"c:\windows" may appear as "/WINDOWS" or "/windows" (or other
things) depending on the precise details of how they were created.
In Windows itself this would not be a problem.
Bug or feature? You decide:
<http://www.tuxera.com/community/ntfs-3g-faq/#posixfilenames1>
This function resolves the true case of each element in the path
and returns the case-sensitive path.
Thus "$g->case_sensitive_path" ("/Windows/System32") might return
"/WINDOWS/system32" (the exact return value would depend on details
of how the directories were originally created under Windows).
Note: This function does not handle drive names, backslashes etc.
See also "$g->realpath".
$content = $g->cat ($path);
Return the contents of the file named "path".
Because, in C, this function returns a "char *", there is no way to
differentiate between a "\0" character in a file and end of string.
To handle binary files, use the "$g->read_file" or "$g->download"
functions.
$checksum = $g->checksum ($csumtype, $path);
This call computes the MD5, SHAx or CRC checksum of the file named
"path".
The type of checksum to compute is given by the "csumtype"
parameter which must have one of the following values:
"crc"
Compute the cyclic redundancy check (CRC) specified by POSIX
for the "cksum" command.
"md5"
Compute the MD5 hash (using the "md5sum" program).
"sha1"
Compute the SHA1 hash (using the "sha1sum" program).
"sha224"
Compute the SHA224 hash (using the "sha224sum" program).
"sha256"
Compute the SHA256 hash (using the "sha256sum" program).
"sha384"
Compute the SHA384 hash (using the "sha384sum" program).
"sha512"
Compute the SHA512 hash (using the "sha512sum" program).
The checksum is returned as a printable string.
To get the checksum for a device, use "$g->checksum_device".
To get the checksums for many files, use "$g->checksums_out".
$checksum = $g->checksum_device ($csumtype, $device);
This call computes the MD5, SHAx or CRC checksum of the contents of
the device named "device". For the types of checksums supported
see the "$g->checksum" command.
$g->checksums_out ($csumtype, $directory, $sumsfile);
This command computes the checksums of all regular files in
"directory" and then emits a list of those checksums to the local
output file "sumsfile".
This can be used for verifying the integrity of a virtual machine.
However to be properly secure you should pay attention to the
output of the checksum command (it uses the ones from GNU
coreutils). In particular when the filename is not printable,
coreutils uses a special backslash syntax. For more information,
see the GNU coreutils info file.
$g->chmod ($mode, $path);
Change the mode (permissions) of "path" to "mode". Only numeric
modes are supported.
Note: When using this command from guestfish, "mode" by default
would be decimal, unless you prefix it with 0 to get octal, ie. use
0700 not 700.
The mode actually set is affected by the umask.
$g->chown ($owner, $group, $path);
Change the file owner to "owner" and group to "group".
Only numeric uid and gid are supported. If you want to use names,
you will need to locate and parse the password file yourself
(Augeas support makes this relatively easy).
$output = $g->command (\@arguments);
This call runs a command from the guest filesystem. The filesystem
must be mounted, and must contain a compatible operating system
(ie. something Linux, with the same or compatible processor
architecture).
The single parameter is an argv-style list of arguments. The first
element is the name of the program to run. Subsequent elements are
parameters. The list must be non-empty (ie. must contain a program
name). Note that the command runs directly, and is not invoked via
the shell (see "$g->sh").
The return value is anything printed to 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 stderr from the command.
The $PATH environment variable will contain at least "/usr/bin" and
"/bin". If you require a program from another location, you should
provide the full path in the first parameter.
Shared libraries and data files required by the program must be
available on filesystems which are mounted in the correct places.
It is the caller's responsibility to ensure all filesystems that
are needed are mounted at the right locations.
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
@lines = $g->command_lines (\@arguments);
This is the same as "$g->command", but splits the result into a
list of lines.
See also: "$g->sh_lines"
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
$g->compress_device_out ($ctype, $device, $zdevice [, level =>
$level]);
This command compresses "device" and writes it out to the local
file "zdevice".
The "ctype" and optional "level" parameters have the same meaning
as in "$g->compress_out".
$g->compress_out ($ctype, $file, $zfile [, level => $level]);
This command compresses "file" and writes it out to the local file
"zfile".
The compression program used is controlled by the "ctype"
parameter. Currently this includes: "compress", "gzip", "bzip2",
"xz" or "lzop". Some compression types may not be supported by
particular builds of libguestfs, in which case you will get an
error containing the substring "not supported".
The optional "level" parameter controls compression level. The
meaning and default for this parameter depends on the compression
program being used.
$g->config ($qemuparam, $qemuvalue);
This can be used to add arbitrary qemu command line parameters of
the form -param value. Actually it's not quite arbitrary - we
prevent you from setting some parameters which would interfere with
parameters that we use.
The first character of "qemuparam" string must be a "-" (dash).
"qemuvalue" can be NULL.
$g->copy_device_to_device ($src, $dest [, srcoffset => $srcoffset] [,
destoffset => $destoffset] [, size => $size] [, sparse => $sparse]);
The four calls "$g->copy_device_to_device",
"$g->copy_device_to_file", "$g->copy_file_to_device", and
"$g->copy_file_to_file" let you copy from a source (device|file) to
a destination (device|file).
Partial copies can be made since you can specify optionally the
source offset, destination offset and size to copy. These values
are all specified in bytes. If not given, the offsets both default
to zero, and the size defaults to copying as much as possible until
we hit the end of the source.
The source and destination may be the same object. However
overlapping regions may not be copied correctly.
If the destination is a file, it is created if required. If the
destination file is not large enough, it is extended.
If the "sparse" flag is true then the call avoids writing blocks
that contain only zeroes, which can help in some situations where
the backing disk is thin-provisioned. Note that unless the target
is already zeroed, using this option will result in incorrect
copying.
$g->copy_device_to_file ($src, $dest [, srcoffset => $srcoffset] [,
destoffset => $destoffset] [, size => $size] [, sparse => $sparse]);
See "$g->copy_device_to_device" for a general overview of this
call.
$g->copy_file_to_device ($src, $dest [, srcoffset => $srcoffset] [,
destoffset => $destoffset] [, size => $size] [, sparse => $sparse]);
See "$g->copy_device_to_device" for a general overview of this
call.
$g->copy_file_to_file ($src, $dest [, srcoffset => $srcoffset] [,
destoffset => $destoffset] [, size => $size] [, sparse => $sparse]);
See "$g->copy_device_to_device" for a general overview of this
call.
This is not the function you want for copying files. This is for
copying blocks within existing files. See "$g->cp", "$g->cp_a" and
"$g->mv" for general file copying and moving functions.
$g->copy_size ($src, $dest, $size);
This command copies exactly "size" bytes from one source device or
file "src" to another destination device or file "dest".
Note this will fail if the source is too short or if the
destination is not large enough.
This function is deprecated. In new code, use the
"copy_device_to_device" call instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->cp ($src, $dest);
This copies a file from "src" to "dest" where "dest" is either a
destination filename or destination directory.
$g->cp_a ($src, $dest);
This copies a file or directory from "src" to "dest" recursively
using the "cp -a" command.
$g->cp_r ($src, $dest);
This copies a file or directory from "src" to "dest" recursively
using the "cp -rP" command.
Most users should use "$g->cp_a" instead. This command is useful
when you don't want to preserve permissions, because the target
filesystem does not support it (primarily when writing to DOS FAT
filesystems).
$g->dd ($src, $dest);
This command copies from one source device or file "src" to another
destination device or file "dest". Normally you would use this to
copy to or from a device or partition, for example to duplicate a
filesystem.
If the destination is a device, it must be as large or larger than
the source file or device, otherwise the copy will fail. This
command cannot do partial copies (see "$g->copy_device_to_device").
This function is deprecated. In new code, use the
"copy_device_to_device" call instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$index = $g->device_index ($device);
This function takes a device name (eg. "/dev/sdb") and returns the
index of the device in the list of devices.
Index numbers start from 0. The named device must exist, for
example as a string returned from "$g->list_devices".
See also "$g->list_devices", "$g->part_to_dev".
$output = $g->df ();
This command runs the "df" command to report disk space used.
This command is mostly useful for interactive sessions. It is not
intended that you try to parse the output string. Use
"$g->statvfs" from programs.
$output = $g->df_h ();
This command runs the "df -h" command to report disk space used in
human-readable format.
This command is mostly useful for interactive sessions. It is not
intended that you try to parse the output string. Use
"$g->statvfs" from programs.
$format = $g->disk_format ($filename);
Detect and return the format of the disk image called "filename".
"filename" can also be a host device, etc. If the format of the
image could not be detected, then "unknown" is returned.
Note that detecting the disk format can be insecure under some
circumstances. See "CVE-2010-3851" in guestfs(3).
See also: "DISK IMAGE FORMATS" in guestfs(3)
$backingfile = $g->disk_has_backing_file ($filename);
Detect and return whether the disk image "filename" has a backing
file.
Note that detecting disk features can be insecure under some
circumstances. See "CVE-2010-3851" in guestfs(3).
$size = $g->disk_virtual_size ($filename);
Detect and return the virtual size in bytes of the disk image
called "filename".
Note that detecting disk features can be insecure under some
circumstances. See "CVE-2010-3851" in guestfs(3).
$kmsgs = $g->dmesg ();
This returns the kernel messages ("dmesg" output) from the guest
kernel. This is sometimes useful for extended debugging of
problems.
Another way to get the same information is to enable verbose
messages with "$g->set_verbose" or by setting the environment
variable "LIBGUESTFS_DEBUG=1" before running the program.
$g->download ($remotefilename, $filename);
Download file "remotefilename" and save it as "filename" on the
local machine.
"filename" can also be a named pipe.
See also "$g->upload", "$g->cat".
$g->download_offset ($remotefilename, $filename, $offset, $size);
Download file "remotefilename" and save it as "filename" on the
local machine.
"remotefilename" is read for "size" bytes starting at "offset"
(this region must be within the file or device).
Note that there is no limit on the amount of data that can be
downloaded with this call, unlike with "$g->pread", and this call
always reads the full amount unless an error occurs.
See also "$g->download", "$g->pread".
$g->drop_caches ($whattodrop);
This instructs the guest kernel to drop its page cache, and/or
dentries and inode caches. The parameter "whattodrop" tells the
kernel what precisely to drop, see
<http://linux-mm.org/Drop_Caches>
Setting "whattodrop" to 3 should drop everything.
This automatically calls sync(2) before the operation, so that the
maximum guest memory is freed.
$sizekb = $g->du ($path);
This command runs the "du -s" command to estimate file space usage
for "path".
"path" can be a file or a directory. If "path" is a directory then
the estimate includes the contents of the directory and all
subdirectories (recursively).
The result is the estimated size in kilobytes (ie. units of 1024
bytes).
$g->e2fsck ($device [, correct => $correct] [, forceall => $forceall]);
This runs the ext2/ext3 filesystem checker on "device". It can
take the following optional arguments:
"correct"
Automatically repair the file system. This option will cause
e2fsck to automatically fix any filesystem problems that can be
safely fixed without human intervention.
This option may not be specified at the same time as the
"forceall" option.
"forceall"
Assume an answer of 'yes' to all questions; allows e2fsck to be
used non-interactively.
This option may not be specified at the same time as the
"correct" option.
$g->e2fsck_f ($device);
This runs "e2fsck -p -f device", ie. runs the ext2/ext3 filesystem
checker on "device", noninteractively (-p), even if the filesystem
appears to be clean (-f).
This function is deprecated. In new code, use the "e2fsck" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$output = $g->echo_daemon (\@words);
This command concatenates the list of "words" passed with single
spaces between them and returns the resulting string.
You can use this command to test the connection through to the
daemon.
See also "$g->ping_daemon".
@lines = $g->egrep ($regex, $path);
This calls the external "egrep" program and returns the matching
lines.
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
This function is deprecated. In new code, use the "grep" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
@lines = $g->egrepi ($regex, $path);
This calls the external "egrep -i" program and returns the matching
lines.
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
This function is deprecated. In new code, use the "grep" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$equality = $g->equal ($file1, $file2);
This compares the two files "file1" and "file2" and returns true if
their content is exactly equal, or false otherwise.
The external cmp(1) program is used for the comparison.
$existsflag = $g->exists ($path);
This returns "true" if and only if there is a file, directory (or
anything) with the given "path" name.
See also "$g->is_file", "$g->is_dir", "$g->stat".
$g->extlinux ($directory);
Install the SYSLINUX bootloader on the device mounted at
"directory". Unlike "$g->syslinux" which requires a FAT
filesystem, this can be used on an ext2/3/4 or btrfs filesystem.
The "directory" parameter can be either a mountpoint, or a
directory within the mountpoint.
You also have to mark the partition as "active"
("$g->part_set_bootable") and a Master Boot Record must be
installed (eg. using "$g->pwrite_device") on the first sector of
the whole disk. The SYSLINUX package comes with some suitable
Master Boot Records. See the extlinux(1) man page for further
information.
Additional configuration can be supplied to SYSLINUX by placing a
file called "extlinux.conf" on the filesystem under "directory".
For further information about the contents of this file, see
extlinux(1).
See also "$g->syslinux".
$g->fallocate ($path, $len);
This command preallocates a file (containing zero bytes) named
"path" of size "len" bytes. If the file exists already, it is
overwritten.
Do not confuse this with the guestfish-specific "alloc" command
which allocates a file in the host and attaches it as a device.
This function is deprecated. In new code, use the "fallocate64"
call instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->fallocate64 ($path, $len);
This command preallocates a file (containing zero bytes) named
"path" of size "len" bytes. If the file exists already, it is
overwritten.
Note that this call allocates disk blocks for the file. To create
a sparse file use "$g->truncate_size" instead.
The deprecated call "$g->fallocate" does the same, but owing to an
oversight it only allowed 30 bit lengths to be specified,
effectively limiting the maximum size of files created through that
call to 1GB.
Do not confuse this with the guestfish-specific "alloc" and
"sparse" commands which create a file in the host and attach it as
a device.
$isavailable = $g->feature_available (\@groups);
This is the same as "$g->available", but unlike that call it
returns a simple true/false boolean result, instead of throwing an
exception if a feature is not found. For other documentation see
"$g->available".
@lines = $g->fgrep ($pattern, $path);
This calls the external "fgrep" program and returns the matching
lines.
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
This function is deprecated. In new code, use the "grep" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
@lines = $g->fgrepi ($pattern, $path);
This calls the external "fgrep -i" program and returns the matching
lines.
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
This function is deprecated. In new code, use the "grep" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$description = $g->file ($path);
This call uses the standard file(1) command to determine the type
or contents of the file.
This call will also transparently look inside various types of
compressed file.
The exact command which runs is "file -zb path". Note in
particular that the filename is not prepended to the output (the -b
option).
The output depends on the output of the underlying file(1) command
and it can change in future in ways beyond our control. In other
words, the output is not guaranteed by the ABI.
See also: file(1), "$g->vfs_type", "$g->lstat", "$g->is_file",
"$g->is_blockdev" (etc), "$g->is_zero".
$arch = $g->file_architecture ($filename);
This detects the architecture of the binary "filename", and returns
it if known.
Currently defined architectures are:
"i386"
This string is returned for all 32 bit i386, i486, i586, i686
binaries irrespective of the precise processor requirements of
the binary.
"x86_64"
64 bit x86-64.
"sparc"
32 bit SPARC.
"sparc64"
64 bit SPARC V9 and above.
"ia64"
Intel Itanium.
"ppc"
32 bit Power PC.
"ppc64"
64 bit Power PC.
Libguestfs may return other architecture strings in future.
The function works on at least the following types of files:
· many types of Un*x and Linux binary
· many types of Un*x and Linux shared library
· Windows Win32 and Win64 binaries
· Windows Win32 and Win64 DLLs
Win32 binaries and DLLs return "i386".
Win64 binaries and DLLs return "x86_64".
· Linux kernel modules
· Linux new-style initrd images
· some non-x86 Linux vmlinuz kernels
What it can't do currently:
· static libraries (libfoo.a)
· Linux old-style initrd as compressed ext2 filesystem (RHEL 3)
· x86 Linux vmlinuz kernels
x86 vmlinuz images (bzImage format) consist of a mix of 16-,
32- and compressed code, and are horribly hard to unpack. If
you want to find the architecture of a kernel, use the
architecture of the associated initrd or kernel module(s)
instead.
$size = $g->filesize ($file);
This command returns the size of "file" in bytes.
To get other stats about a file, use "$g->stat", "$g->lstat",
"$g->is_dir", "$g->is_file" etc. To get the size of block devices,
use "$g->blockdev_getsize64".
$fsavail = $g->filesystem_available ($filesystem);
Check whether libguestfs supports the named filesystem. The
argument "filesystem" is a filesystem name, such as "ext3".
You must call "$g->launch" before using this command.
This is mainly useful as a negative test. If this returns true, it
doesn't mean that a particular filesystem can be created or
mounted, since filesystems can fail for other reasons such as it
being a later version of the filesystem, or having incompatible
features, or lacking the right mkfs.<fs> tool.
See also "$g->available", "$g->feature_available", "AVAILABILITY"
in guestfs(3).
$g->fill ($c, $len, $path);
This command creates a new file called "path". The initial content
of the file is "len" octets of "c", where "c" must be a number in
the range "[0..255]".
To fill a file with zero bytes (sparsely), it is much more
efficient to use "$g->truncate_size". To create a file with a
pattern of repeating bytes use "$g->fill_pattern".
$g->fill_dir ($dir, $nr);
This function, useful for testing filesystems, creates "nr" empty
files in the directory "dir" with names 00000000 through "nr-1"
(ie. each file name is 8 digits long padded with zeroes).
$g->fill_pattern ($pattern, $len, $path);
This function is like "$g->fill" except that it creates a new file
of length "len" containing the repeating pattern of bytes in
"pattern". The pattern is truncated if necessary to ensure the
length of the file is exactly "len" bytes.
@names = $g->find ($directory);
This command lists out all files and directories, recursively,
starting at "directory". It is essentially equivalent to running
the shell command "find directory -print" but some post-processing
happens on the output, described below.
This returns a list of strings without any prefix. Thus if the
directory structure was:
/tmp/a
/tmp/b
/tmp/c/d
then the returned list from "$g->find" "/tmp" would be 4 elements:
a
b
c
c/d
If "directory" is not a directory, then this command returns an
error.
The returned list is sorted.
$g->find0 ($directory, $files);
This command lists out all files and directories, recursively,
starting at "directory", placing the resulting list in the external
file called "files".
This command works the same way as "$g->find" with the following
exceptions:
· The resulting list is written to an external file.
· Items (filenames) in the result are separated by "\0"
characters. See find(1) option -print0.
· The result list is not sorted.
$device = $g->findfs_label ($label);
This command searches the filesystems and returns the one which has
the given label. An error is returned if no such filesystem can be
found.
To find the label of a filesystem, use "$g->vfs_label".
$device = $g->findfs_uuid ($uuid);
This command searches the filesystems and returns the one which has
the given UUID. An error is returned if no such filesystem can be
found.
To find the UUID of a filesystem, use "$g->vfs_uuid".
$status = $g->fsck ($fstype, $device);
This runs the filesystem checker (fsck) on "device" which should
have filesystem type "fstype".
The returned integer is the status. See fsck(8) for the list of
status codes from "fsck".
Notes:
· Multiple status codes can be summed together.
· A non-zero return code can mean "success", for example if
errors have been corrected on the filesystem.
· Checking or repairing NTFS volumes is not supported (by linux-
ntfs).
This command is entirely equivalent to running "fsck -a -t fstype
device".
$g->fstrim ($mountpoint [, offset => $offset] [, length => $length] [,
minimumfreeextent => $minimumfreeextent]);
Trim the free space in the filesystem mounted on "mountpoint". The
filesystem must be mounted read-write.
The filesystem contents are not affected, but any free space in the
filesystem is "trimmed", that is, given back to the host device,
thus making disk images more sparse, allowing unused space in qcow2
files to be reused, etc.
This operation requires support in libguestfs, the mounted
filesystem, the host filesystem, qemu and the host kernel. If this
support isn't present it may give an error or even appear to run
but do nothing.
See also "$g->zero_free_space". That is a slightly different
operation that turns free space in the filesystem into zeroes. It
is valid to call "$g->fstrim" either instead of, or after calling
"$g->zero_free_space".
$append = $g->get_append ();
Return the additional kernel options which are added to the guest
kernel command line.
If "NULL" then no options are added.
$backend = $g->get_attach_method ();
Return the current backend.
See "$g->set_backend" and "BACKEND" in guestfs(3).
This function is deprecated. In new code, use the "get_backend"
call instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$autosync = $g->get_autosync ();
Get the autosync flag.
$backend = $g->get_backend ();
Return the current backend.
This handle property was previously called the "attach method".
See "$g->set_backend" and "BACKEND" in guestfs(3).
$cachedir = $g->get_cachedir ();
Get the directory used by the handle to store the appliance cache.
$direct = $g->get_direct ();
Return the direct appliance mode flag.
$attrs = $g->get_e2attrs ($file);
This returns the file attributes associated with "file".
The attributes are a set of bits associated with each inode which
affect the behaviour of the file. The attributes are returned as a
string of letters (described below). The string may be empty,
indicating that no file attributes are set for this file.
These attributes are only present when the file is located on an
ext2/3/4 filesystem. Using this call on other filesystem types
will result in an error.
The characters (file attributes) in the returned string are
currently:
'A' When the file is accessed, its atime is not modified.
'a' The file is append-only.
'c' The file is compressed on-disk.
'D' (Directories only.) Changes to this directory are written
synchronously to disk.
'd' The file is not a candidate for backup (see dump(8)).
'E' The file has compression errors.
'e' The file is using extents.
'h' The file is storing its blocks in units of the filesystem
blocksize instead of sectors.
'I' (Directories only.) The directory is using hashed trees.
'i' The file is immutable. It cannot be modified, deleted or
renamed. No link can be created to this file.
'j' The file is data-journaled.
's' When the file is deleted, all its blocks will be zeroed.
'S' Changes to this file are written synchronously to disk.
'T' (Directories only.) This is a hint to the block allocator that
subdirectories contained in this directory should be spread
across blocks. If not present, the block allocator will try to
group subdirectories together.
't' For a file, this disables tail-merging. (Not used by upstream
implementations of ext2.)
'u' When the file is deleted, its blocks will be saved, allowing
the file to be undeleted.
'X' The raw contents of the compressed file may be accessed.
'Z' The compressed file is dirty.
More file attributes may be added to this list later. Not all file
attributes may be set for all kinds of files. For detailed
information, consult the chattr(1) man page.
See also "$g->set_e2attrs".
Don't confuse these attributes with extended attributes (see
"$g->getxattr").
$generation = $g->get_e2generation ($file);
This returns the ext2 file generation of a file. The generation
(which used to be called the "version") is a number associated with
an inode. This is most commonly used by NFS servers.
The generation is only present when the file is located on an
ext2/3/4 filesystem. Using this call on other filesystem types
will result in an error.
See "$g->set_e2generation".
$label = $g->get_e2label ($device);
This returns the ext2/3/4 filesystem label of the filesystem on
"device".
This function is deprecated. In new code, use the "vfs_label" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$uuid = $g->get_e2uuid ($device);
This returns the ext2/3/4 filesystem UUID of the filesystem on
"device".
This function is deprecated. In new code, use the "vfs_uuid" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$challenge = $g->get_libvirt_requested_credential_challenge ($index);
Get the challenge (provided by libvirt) for the "index"'th
requested credential. If libvirt did not provide a challenge, this
returns the empty string "".
See "LIBVIRT AUTHENTICATION" in guestfs(3) for documentation and
example code.
$defresult = $g->get_libvirt_requested_credential_defresult ($index);
Get the default result (provided by libvirt) for the "index"'th
requested credential. If libvirt did not provide a default result,
this returns the empty string "".
See "LIBVIRT AUTHENTICATION" in guestfs(3) for documentation and
example code.
$prompt = $g->get_libvirt_requested_credential_prompt ($index);
Get the prompt (provided by libvirt) for the "index"'th requested
credential. If libvirt did not provide a prompt, this returns the
empty string "".
See "LIBVIRT AUTHENTICATION" in guestfs(3) for documentation and
example code.
@creds = $g->get_libvirt_requested_credentials ();
This should only be called during the event callback for events of
type "GUESTFS_EVENT_LIBVIRT_AUTH".
Return the list of credentials requested by libvirt. Possible
values are a subset of the strings provided when you called
"$g->set_libvirt_supported_credentials".
See "LIBVIRT AUTHENTICATION" in guestfs(3) for documentation and
example code.
$memsize = $g->get_memsize ();
This gets the memory size in megabytes allocated to the qemu
subprocess.
If "$g->set_memsize" was not called on this handle, and if
"LIBGUESTFS_MEMSIZE" was not set, then this returns the compiled-in
default value for memsize.
For more information on the architecture of libguestfs, see
guestfs(3).
$network = $g->get_network ();
This returns the enable network flag.
$path = $g->get_path ();
Return the current search path.
This is always non-NULL. If it wasn't set already, then this will
return the default path.
$pgroup = $g->get_pgroup ();
This returns the process group flag.
$pid = $g->get_pid ();
Return the process ID of the qemu subprocess. If there is no qemu
subprocess, then this will return an error.
This is an internal call used for debugging and testing.
$program = $g->get_program ();
Get the program name. See "$g->set_program".
$qemu = $g->get_qemu ();
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.
$recoveryproc = $g->get_recovery_proc ();
Return the recovery process enabled flag.
$selinux = $g->get_selinux ();
This returns the current setting of the selinux flag which is
passed to the appliance at boot time. See "$g->set_selinux".
For more information on the architecture of libguestfs, see
guestfs(3).
$smp = $g->get_smp ();
This returns the number of virtual CPUs assigned to the appliance.
$state = $g->get_state ();
This returns the current state as an opaque integer. This is only
useful for printing debug and internal error messages.
For more information on states, see guestfs(3).
$tmpdir = $g->get_tmpdir ();
Get the directory used by the handle to store temporary files.
$trace = $g->get_trace ();
Return the command trace flag.
$mask = $g->get_umask ();
Return the current umask. By default the umask is 022 unless it
has been set by calling "$g->umask".
$verbose = $g->get_verbose ();
This returns the verbose messages flag.
$context = $g->getcon ();
This gets the SELinux security context of the daemon.
See the documentation about SELINUX in guestfs(3), and "$g->setcon"
$xattr = $g->getxattr ($path, $name);
Get a single extended attribute from file "path" named "name".
This call follows symlinks. If you want to lookup an extended
attribute for the symlink itself, use "$g->lgetxattr".
Normally it is better to get all extended attributes from a file in
one go by calling "$g->getxattrs". However some Linux filesystem
implementations are buggy and do not provide a way to list out
attributes. For these filesystems (notably ntfs-3g) you have to
know the names of the extended attributes you want in advance and
call this function.
Extended attribute values are blobs of binary data. If there is no
extended attribute named "name", this returns an error.
See also: "$g->getxattrs", "$g->lgetxattr", attr(5).
@xattrs = $g->getxattrs ($path);
This call lists the extended attributes of the file or directory
"path".
At the system call level, this is a combination of the listxattr(2)
and getxattr(2) calls.
See also: "$g->lgetxattrs", attr(5).
@paths = $g->glob_expand ($pattern);
This command searches for all the pathnames matching "pattern"
according to the wildcard expansion rules used by the shell.
If no paths match, then this returns an empty list (note: not an
error).
It is just a wrapper around the C glob(3) function with flags
"GLOB_MARK|GLOB_BRACE". See that manual page for more details.
Notice that there is no equivalent command for expanding a device
name (eg. "/dev/sd*"). Use "$g->list_devices",
"$g->list_partitions" etc functions instead.
@lines = $g->grep ($regex, $path [, extended => $extended] [, fixed =>
$fixed] [, insensitive => $insensitive] [, compressed => $compressed]);
This calls the external "grep" program and returns the matching
lines.
The optional flags are:
"extended"
Use extended regular expressions. This is the same as using
the -E flag.
"fixed"
Match fixed (don't use regular expressions). This is the same
as using the -F flag.
"insensitive"
Match case-insensitive. This is the same as using the -i flag.
"compressed"
Use "zgrep" instead of "grep". This allows the input to be
compress- or gzip-compressed.
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
@lines = $g->grep_opts ($regex, $path [, extended => $extended] [,
fixed => $fixed] [, insensitive => $insensitive] [, compressed =>
$compressed]);
This is an alias of "grep".
@lines = $g->grepi ($regex, $path);
This calls the external "grep -i" program and returns the matching
lines.
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
This function is deprecated. In new code, use the "grep" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->grub_install ($root, $device);
This command installs GRUB 1 (the Grand Unified Bootloader) on
"device", with the root directory being "root".
Notes:
· There is currently no way in the API to install grub2, which is
used by most modern Linux guests. It is possible to run the
grub2 command from the guest, although see the caveats in
"RUNNING COMMANDS" in guestfs(3).
· This uses "grub-install" from the host. Unfortunately grub is
not always compatible with itself, so this only works in rather
narrow circumstances. Careful testing with each guest version
is advisable.
· If grub-install reports the error "No suitable drive was found
in the generated device map." it may be that you need to
create a "/boot/grub/device.map" file first that contains the
mapping between grub device names and Linux device names. It
is usually sufficient to create a file containing:
(hd0) /dev/vda
replacing "/dev/vda" with the name of the installation device.
@lines = $g->head ($path);
This command returns up to the first 10 lines of a file as a list
of strings.
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
@lines = $g->head_n ($nrlines, $path);
If the parameter "nrlines" is a positive number, this returns the
first "nrlines" lines of the file "path".
If the parameter "nrlines" is a negative number, this returns lines
from the file "path", excluding the last "nrlines" lines.
If the parameter "nrlines" is zero, this returns an empty list.
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
$dump = $g->hexdump ($path);
This runs "hexdump -C" on the given "path". The result is the
human-readable, canonical hex dump of the file.
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
$g->hivex_close ();
Close the current hivex handle.
This is a wrapper around the hivex(3) call of the same name.
$g->hivex_commit ($filename);
Commit (write) changes to the hive.
If the optional "filename" parameter is null, then the changes are
written back to the same hive that was opened. If this is not null
then they are written to the alternate filename given and the
original hive is left untouched.
This is a wrapper around the hivex(3) call of the same name.
$nodeh = $g->hivex_node_add_child ($parent, $name);
Add a child node to "parent" named "name".
This is a wrapper around the hivex(3) call of the same name.
@nodehs = $g->hivex_node_children ($nodeh);
Return the list of nodes which are subkeys of "nodeh".
This is a wrapper around the hivex(3) call of the same name.
$g->hivex_node_delete_child ($nodeh);
Delete "nodeh", recursively if necessary.
This is a wrapper around the hivex(3) call of the same name.
$child = $g->hivex_node_get_child ($nodeh, $name);
Return the child of "nodeh" with the name "name", if it exists.
This can return 0 meaning the name was not found.
This is a wrapper around the hivex(3) call of the same name.
$valueh = $g->hivex_node_get_value ($nodeh, $key);
Return the value attached to "nodeh" which has the name "key", if
it exists. This can return 0 meaning the key was not found.
This is a wrapper around the hivex(3) call of the same name.
$name = $g->hivex_node_name ($nodeh);
Return the name of "nodeh".
This is a wrapper around the hivex(3) call of the same name.
$parent = $g->hivex_node_parent ($nodeh);
Return the parent node of "nodeh".
This is a wrapper around the hivex(3) call of the same name.
$g->hivex_node_set_value ($nodeh, $key, $t, $val);
Set or replace a single value under the node "nodeh". The "key" is
the name, "t" is the type, and "val" is the data.
This is a wrapper around the hivex(3) call of the same name.
@valuehs = $g->hivex_node_values ($nodeh);
Return the array of (key, datatype, data) tuples attached to
"nodeh".
This is a wrapper around the hivex(3) call of the same name.
$g->hivex_open ($filename [, verbose => $verbose] [, debug => $debug]
[, write => $write]);
Open the Windows Registry hive file named "filename". If there was
any previous hivex handle associated with this guestfs session,
then it is closed.
This is a wrapper around the hivex(3) call of the same name.
$nodeh = $g->hivex_root ();
Return the root node of the hive.
This is a wrapper around the hivex(3) call of the same name.
$key = $g->hivex_value_key ($valueh);
Return the key (name) field of a (key, datatype, data) tuple.
This is a wrapper around the hivex(3) call of the same name.
$datatype = $g->hivex_value_type ($valueh);
Return the data type field from a (key, datatype, data) tuple.
This is a wrapper around the hivex(3) call of the same name.
$databuf = $g->hivex_value_utf8 ($valueh);
This calls "$g->hivex_value_value" (which returns the data field
from a hivex value tuple). It then assumes that the field is a
UTF-16LE string and converts the result to UTF-8 (or if this is not
possible, it returns an error).
This is useful for reading strings out of the Windows registry.
However it is not foolproof because the registry is not strongly-
typed and fields can contain arbitrary or unexpected data.
$databuf = $g->hivex_value_value ($valueh);
Return the data field of a (key, datatype, data) tuple.
This is a wrapper around the hivex(3) call of the same name.
See also: "$g->hivex_value_utf8".
$content = $g->initrd_cat ($initrdpath, $filename);
This command unpacks the file "filename" from the initrd file
called "initrdpath". The filename must be given without the
initial "/" character.
For example, in guestfish you could use the following command to
examine the boot script (usually called "/init") contained in a
Linux initrd or initramfs image:
initrd-cat /boot/initrd-<version>.img init
See also "$g->initrd_list".
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
@filenames = $g->initrd_list ($path);
This command lists out files contained in an initrd.
The files are listed without any initial "/" character. The files
are listed in the order they appear (not necessarily alphabetical).
Directory names are listed as separate items.
Old Linux kernels (2.4 and earlier) used a compressed ext2
filesystem as initrd. We only support the newer initramfs format
(compressed cpio files).
$wd = $g->inotify_add_watch ($path, $mask);
Watch "path" for the events listed in "mask".
Note that if "path" is a directory then events within that
directory are watched, but this does not happen recursively (in
subdirectories).
Note for non-C or non-Linux callers: the inotify events are defined
by the Linux kernel ABI and are listed in
"/usr/include/sys/inotify.h".
$g->inotify_close ();
This closes the inotify handle which was previously opened by
inotify_init. It removes all watches, throws away any pending
events, and deallocates all resources.
@paths = $g->inotify_files ();
This function is a helpful wrapper around "$g->inotify_read" which
just returns a list of pathnames of objects that were touched. The
returned pathnames are sorted and deduplicated.
$g->inotify_init ($maxevents);
This command creates a new inotify handle. The inotify subsystem
can be used to notify events which happen to objects in the guest
filesystem.
"maxevents" is the maximum number of events which will be queued up
between calls to "$g->inotify_read" or "$g->inotify_files". If
this is passed as 0, then the kernel (or previously set) default is
used. For Linux 2.6.29 the default was 16384 events. Beyond this
limit, the kernel throws away events, but records the fact that it
threw them away by setting a flag "IN_Q_OVERFLOW" in the returned
structure list (see "$g->inotify_read").
Before any events are generated, you have to add some watches to
the internal watch list. See: "$g->inotify_add_watch" and
"$g->inotify_rm_watch".
Queued up events should be read periodically by calling
"$g->inotify_read" (or "$g->inotify_files" which is just a helpful
wrapper around "$g->inotify_read"). If you don't read the events
out often enough then you risk the internal queue overflowing.
The handle should be closed after use by calling
"$g->inotify_close". This also removes any watches automatically.
See also inotify(7) for an overview of the inotify interface as
exposed by the Linux kernel, which is roughly what we expose via
libguestfs. Note that there is one global inotify handle per
libguestfs instance.
@events = $g->inotify_read ();
Return the complete queue of events that have happened since the
previous read call.
If no events have happened, this returns an empty list.
Note: In order to make sure that all events have been read, you
must call this function repeatedly until it returns an empty list.
The reason is that the call will read events up to the maximum
appliance-to-host message size and leave remaining events in the
queue.
$g->inotify_rm_watch ($wd);
Remove a previously defined inotify watch. See
"$g->inotify_add_watch".
$arch = $g->inspect_get_arch ($root);
This returns the architecture of the inspected operating system.
The possible return values are listed under
"$g->file_architecture".
If the architecture could not be determined, then the string
"unknown" is returned.
Please read "INSPECTION" in guestfs(3) for more details.
$distro = $g->inspect_get_distro ($root);
This returns the distro (distribution) of the inspected operating
system.
Currently defined distros are:
"archlinux"
Arch Linux.
"buildroot"
Buildroot-derived distro, but not one we specifically
recognize.
"centos"
CentOS.
"cirros"
Cirros.
"debian"
Debian.
"fedora"
Fedora.
"freedos"
FreeDOS.
"gentoo"
Gentoo.
"linuxmint"
Linux Mint.
"mageia"
Mageia.
"mandriva"
Mandriva.
"meego"
MeeGo.
"openbsd"
OpenBSD.
"opensuse"
OpenSUSE.
"pardus"
Pardus.
"redhat-based"
Some Red Hat-derived distro.
"rhel"
Red Hat Enterprise Linux.
"scientificlinux"
Scientific Linux.
"slackware"
Slackware.
"sles"
SuSE Linux Enterprise Server or Desktop.
"suse-based"
Some openSuSE-derived distro.
"ttylinux"
ttylinux.
"ubuntu"
Ubuntu.
"unknown"
The distro could not be determined.
"windows"
Windows does not have distributions. This string is returned
if the OS type is Windows.
Future versions of libguestfs may return other strings here. The
caller should be prepared to handle any string.
Please read "INSPECTION" in guestfs(3) for more details.
%drives = $g->inspect_get_drive_mappings ($root);
This call is useful for Windows which uses a primitive system of
assigning drive letters (like "C:") to partitions. This inspection
API examines the Windows Registry to find out how disks/partitions
are mapped to drive letters, and returns a hash table as in the
example below:
C => /dev/vda2
E => /dev/vdb1
F => /dev/vdc1
Note that keys are drive letters. For Windows, the key is case
insensitive and just contains the drive letter, without the
customary colon separator character.
In future we may support other operating systems that also used
drive letters, but the keys for those might not be case insensitive
and might be longer than 1 character. For example in OS-9, hard
drives were named "h0", "h1" etc.
For Windows guests, currently only hard drive mappings are
returned. Removable disks (eg. DVD-ROMs) are ignored.
For guests that do not use drive mappings, or if the drive mappings
could not be determined, this returns an empty hash table.
Please read "INSPECTION" in guestfs(3) for more details. See also
"$g->inspect_get_mountpoints", "$g->inspect_get_filesystems".
@filesystems = $g->inspect_get_filesystems ($root);
This returns a list of all the filesystems that we think are
associated with this operating system. This includes the root
filesystem, other ordinary filesystems, and non-mounted devices
like swap partitions.
In the case of a multi-boot virtual machine, it is possible for a
filesystem to be shared between operating systems.
Please read "INSPECTION" in guestfs(3) for more details. See also
"$g->inspect_get_mountpoints".
$format = $g->inspect_get_format ($root);
This returns the format of the inspected operating system. You can
use it to detect install images, live CDs and similar.
Currently defined formats are:
"installed"
This is an installed operating system.
"installer"
The disk image being inspected is not an installed operating
system, but a bootable install disk, live CD, or similar.
"unknown"
The format of this disk image is not known.
Future versions of libguestfs may return other strings here. The
caller should be prepared to handle any string.
Please read "INSPECTION" in guestfs(3) for more details.
$hostname = $g->inspect_get_hostname ($root);
This function returns the hostname of the operating system as found
by inspection of the guest's configuration files.
If the hostname could not be determined, then the string "unknown"
is returned.
Please read "INSPECTION" in guestfs(3) for more details.
$icon = $g->inspect_get_icon ($root [, favicon => $favicon] [,
highquality => $highquality]);
This function returns an icon corresponding to the inspected
operating system. The icon is returned as a buffer containing a
PNG image (re-encoded to PNG if necessary).
If it was not possible to get an icon this function returns a zero-
length (non-NULL) buffer. Callers must check for this case.
Libguestfs will start by looking for a file called
"/etc/favicon.png" or "C:\etc\favicon.png" and if it has the
correct format, the contents of this file will be returned. You
can disable favicons by passing the optional "favicon" boolean as
false (default is true).
If finding the favicon fails, then we look in other places in the
guest for a suitable icon.
If the optional "highquality" boolean is true then only high
quality icons are returned, which means only icons of high
resolution with an alpha channel. The default (false) is to return
any icon we can, even if it is of substandard quality.
Notes:
· Unlike most other inspection API calls, the guest's disks must
be mounted up before you call this, since it needs to read
information from the guest filesystem during the call.
· Security: The icon data comes from the untrusted guest, and
should be treated with caution. PNG files have been known to
contain exploits. Ensure that libpng (or other relevant
libraries) are fully up to date before trying to process or
display the icon.
· The PNG image returned can be any size. It might not be
square. Libguestfs tries to return the largest, highest
quality icon available. The application must scale the icon to
the required size.
· Extracting icons from Windows guests requires the external
"wrestool" program from the "icoutils" package, and several
programs ("bmptopnm", "pnmtopng", "pamcut") from the "netpbm"
package. These must be installed separately.
· Operating system icons are usually trademarks. Seek legal
advice before using trademarks in applications.
$major = $g->inspect_get_major_version ($root);
This returns the major version number of the inspected operating
system.
Windows uses a consistent versioning scheme which is not reflected
in the popular public names used by the operating system. Notably
the operating system known as "Windows 7" is really version 6.1
(ie. major = 6, minor = 1). You can find out the real versions
corresponding to releases of Windows by consulting Wikipedia or
MSDN.
If the version could not be determined, then 0 is returned.
Please read "INSPECTION" in guestfs(3) for more details.
$minor = $g->inspect_get_minor_version ($root);
This returns the minor version number of the inspected operating
system.
If the version could not be determined, then 0 is returned.
Please read "INSPECTION" in guestfs(3) for more details. See also
"$g->inspect_get_major_version".
%mountpoints = $g->inspect_get_mountpoints ($root);
This returns a hash of where we think the filesystems associated
with this operating system should be mounted. Callers should note
that this is at best an educated guess made by reading
configuration files such as "/etc/fstab". In particular note that
this may return filesystems which are non-existent or not mountable
and callers should be prepared to handle or ignore failures if they
try to mount them.
Each element in the returned hashtable has a key which is the path
of the mountpoint (eg. "/boot") and a value which is the filesystem
that would be mounted there (eg. "/dev/sda1").
Non-mounted devices such as swap devices are not returned in this
list.
For operating systems like Windows which still use drive letters,
this call will only return an entry for the first drive "mounted
on" "/". For information about the mapping of drive letters to
partitions, see "$g->inspect_get_drive_mappings".
Please read "INSPECTION" in guestfs(3) for more details. See also
"$g->inspect_get_filesystems".
$packageformat = $g->inspect_get_package_format ($root);
This function and "$g->inspect_get_package_management" return the
package format and package management tool used by the inspected
operating system. For example for Fedora these functions would
return "rpm" (package format) and "yum" (package management).
This returns the string "unknown" if we could not determine the
package format or if the operating system does not have a real
packaging system (eg. Windows).
Possible strings include: "rpm", "deb", "ebuild", "pisi", "pacman",
"pkgsrc". Future versions of libguestfs may return other strings.
Please read "INSPECTION" in guestfs(3) for more details.
$packagemanagement = $g->inspect_get_package_management ($root);
"$g->inspect_get_package_format" and this function return the
package format and package management tool used by the inspected
operating system. For example for Fedora these functions would
return "rpm" (package format) and "yum" (package management).
This returns the string "unknown" if we could not determine the
package management tool or if the operating system does not have a
real packaging system (eg. Windows).
Possible strings include: "yum", "up2date", "apt" (for all Debian
derivatives), "portage", "pisi", "pacman", "urpmi", "zypper".
Future versions of libguestfs may return other strings.
Please read "INSPECTION" in guestfs(3) for more details.
$product = $g->inspect_get_product_name ($root);
This returns the product name of the inspected operating system.
The product name is generally some freeform string which can be
displayed to the user, but should not be parsed by programs.
If the product name could not be determined, then the string
"unknown" is returned.
Please read "INSPECTION" in guestfs(3) for more details.
$variant = $g->inspect_get_product_variant ($root);
This returns the product variant of the inspected operating system.
For Windows guests, this returns the contents of the Registry key
"HKLM\Software\Microsoft\Windows NT\CurrentVersion"
"InstallationType" which is usually a string such as "Client" or
"Server" (other values are possible). This can be used to
distinguish consumer and enterprise versions of Windows that have
the same version number (for example, Windows 7 and Windows 2008
Server are both version 6.1, but the former is "Client" and the
latter is "Server").
For enterprise Linux guests, in future we intend this to return the
product variant such as "Desktop", "Server" and so on. But this is
not implemented at present.
If the product variant could not be determined, then the string
"unknown" is returned.
Please read "INSPECTION" in guestfs(3) for more details. See also
"$g->inspect_get_product_name", "$g->inspect_get_major_version".
@roots = $g->inspect_get_roots ();
This function is a convenient way to get the list of root devices,
as returned from a previous call to "$g->inspect_os", but without
redoing the whole inspection process.
This returns an empty list if either no root devices were found or
the caller has not called "$g->inspect_os".
Please read "INSPECTION" in guestfs(3) for more details.
$name = $g->inspect_get_type ($root);
This returns the type of the inspected operating system. Currently
defined types are:
"linux"
Any Linux-based operating system.
"windows"
Any Microsoft Windows operating system.
"freebsd"
FreeBSD.
"netbsd"
NetBSD.
"openbsd"
OpenBSD.
"hurd"
GNU/Hurd.
"dos"
MS-DOS, FreeDOS and others.
"unknown"
The operating system type could not be determined.
Future versions of libguestfs may return other strings here. The
caller should be prepared to handle any string.
Please read "INSPECTION" in guestfs(3) for more details.
$controlset = $g->inspect_get_windows_current_control_set ($root);
This returns the Windows CurrentControlSet of the inspected guest.
The CurrentControlSet is a registry key name such as
"ControlSet001".
This call assumes that the guest is Windows and that the Registry
could be examined by inspection. If this is not the case then an
error is returned.
Please read "INSPECTION" in guestfs(3) for more details.
$systemroot = $g->inspect_get_windows_systemroot ($root);
This returns the Windows systemroot of the inspected guest. The
systemroot is a directory path such as "/WINDOWS".
This call assumes that the guest is Windows and that the systemroot
could be determined by inspection. If this is not the case then an
error is returned.
Please read "INSPECTION" in guestfs(3) for more details.
$live = $g->inspect_is_live ($root);
If "$g->inspect_get_format" returns "installer" (this is an install
disk), then this returns true if a live image was detected on the
disk.
Please read "INSPECTION" in guestfs(3) for more details.
$multipart = $g->inspect_is_multipart ($root);
If "$g->inspect_get_format" returns "installer" (this is an install
disk), then this returns true if the disk is part of a set.
Please read "INSPECTION" in guestfs(3) for more details.
$netinst = $g->inspect_is_netinst ($root);
If "$g->inspect_get_format" returns "installer" (this is an install
disk), then this returns true if the disk is a network installer,
ie. not a self-contained install CD but one which is likely to
require network access to complete the install.
Please read "INSPECTION" in guestfs(3) for more details.
@applications = $g->inspect_list_applications ($root);
Return the list of applications installed in the operating system.
Note: This call works differently from other parts of the
inspection API. You have to call "$g->inspect_os", then
"$g->inspect_get_mountpoints", then mount up the disks, before
calling this. Listing applications is a significantly more
difficult operation which requires access to the full filesystem.
Also note that unlike the other "$g->inspect_get_*" calls which are
just returning data cached in the libguestfs handle, this call
actually reads parts of the mounted filesystems during the call.
This returns an empty list if the inspection code was not able to
determine the list of applications.
The application structure contains the following fields:
"app_name"
The name of the application. For Red Hat-derived and Debian-
derived Linux guests, this is the package name.
"app_display_name"
The display name of the application, sometimes localized to the
install language of the guest operating system.
If unavailable this is returned as an empty string "". Callers
needing to display something can use "app_name" instead.
"app_epoch"
For package managers which use epochs, this contains the epoch
of the package (an integer). If unavailable, this is returned
as 0.
"app_version"
The version string of the application or package. If
unavailable this is returned as an empty string "".
"app_release"
The release string of the application or package, for package
managers that use this. If unavailable this is returned as an
empty string "".
"app_install_path"
The installation path of the application (on operating systems
such as Windows which use installation paths). This path is in
the format used by the guest operating system, it is not a
libguestfs path.
If unavailable this is returned as an empty string "".
"app_trans_path"
The install path translated into a libguestfs path. If
unavailable this is returned as an empty string "".
"app_publisher"
The name of the publisher of the application, for package
managers that use this. If unavailable this is returned as an
empty string "".
"app_url"
The URL (eg. upstream URL) of the application. If unavailable
this is returned as an empty string "".
"app_source_package"
For packaging systems which support this, the name of the
source package. If unavailable this is returned as an empty
string "".
"app_summary"
A short (usually one line) description of the application or
package. If unavailable this is returned as an empty string
"".
"app_description"
A longer description of the application or package. If
unavailable this is returned as an empty string "".
Please read "INSPECTION" in guestfs(3) for more details.
This function is deprecated. In new code, use the
"inspect_list_applications2" call instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
@applications2 = $g->inspect_list_applications2 ($root);
Return the list of applications installed in the operating system.
Note: This call works differently from other parts of the
inspection API. You have to call "$g->inspect_os", then
"$g->inspect_get_mountpoints", then mount up the disks, before
calling this. Listing applications is a significantly more
difficult operation which requires access to the full filesystem.
Also note that unlike the other "$g->inspect_get_*" calls which are
just returning data cached in the libguestfs handle, this call
actually reads parts of the mounted filesystems during the call.
This returns an empty list if the inspection code was not able to
determine the list of applications.
The application structure contains the following fields:
"app2_name"
The name of the application. For Red Hat-derived and Debian-
derived Linux guests, this is the package name.
"app2_display_name"
The display name of the application, sometimes localized to the
install language of the guest operating system.
If unavailable this is returned as an empty string "". Callers
needing to display something can use "app2_name" instead.
"app2_epoch"
For package managers which use epochs, this contains the epoch
of the package (an integer). If unavailable, this is returned
as 0.
"app2_version"
The version string of the application or package. If
unavailable this is returned as an empty string "".
"app2_release"
The release string of the application or package, for package
managers that use this. If unavailable this is returned as an
empty string "".
"app2_arch"
The architecture string of the application or package, for
package managers that use this. If unavailable this is
returned as an empty string "".
"app2_install_path"
The installation path of the application (on operating systems
such as Windows which use installation paths). This path is in
the format used by the guest operating system, it is not a
libguestfs path.
If unavailable this is returned as an empty string "".
"app2_trans_path"
The install path translated into a libguestfs path. If
unavailable this is returned as an empty string "".
"app2_publisher"
The name of the publisher of the application, for package
managers that use this. If unavailable this is returned as an
empty string "".
"app2_url"
The URL (eg. upstream URL) of the application. If unavailable
this is returned as an empty string "".
"app2_source_package"
For packaging systems which support this, the name of the
source package. If unavailable this is returned as an empty
string "".
"app2_summary"
A short (usually one line) description of the application or
package. If unavailable this is returned as an empty string
"".
"app2_description"
A longer description of the application or package. If
unavailable this is returned as an empty string "".
Please read "INSPECTION" in guestfs(3) for more details.
@roots = $g->inspect_os ();
This function uses other libguestfs functions and certain
heuristics to inspect the disk(s) (usually disks belonging to a
virtual machine), looking for operating systems.
The list returned is empty if no operating systems were found.
If one operating system was found, then this returns a list with a
single element, which is the name of the root filesystem of this
operating system. It is also possible for this function to return
a list containing more than one element, indicating a dual-boot or
multi-boot virtual machine, with each element being the root
filesystem of one of the operating systems.
You can pass the root string(s) returned to other
"$g->inspect_get_*" functions in order to query further information
about each operating system, such as the name and version.
This function uses other libguestfs features such as "$g->mount_ro"
and "$g->umount_all" in order to mount and unmount filesystems and
look at the contents. This should be called with no disks
currently mounted. The function may also use Augeas, so any
existing Augeas handle will be closed.
This function cannot decrypt encrypted disks. The caller must do
that first (supplying the necessary keys) if the disk is encrypted.
Please read "INSPECTION" in guestfs(3) for more details.
See also "$g->list_filesystems".
$flag = $g->is_blockdev ($path [, followsymlinks => $followsymlinks]);
This returns "true" if and only if there is a block device with the
given "path" name.
If the optional flag "followsymlinks" is true, then a symlink (or
chain of symlinks) that ends with a block device also causes the
function to return true.
See also "$g->stat".
$flag = $g->is_blockdev_opts ($path [, followsymlinks =>
$followsymlinks]);
This is an alias of "is_blockdev".
$busy = $g->is_busy ();
This always returns false. This function is deprecated with no
replacement. Do not use this function.
For more information on states, see guestfs(3).
$flag = $g->is_chardev ($path [, followsymlinks => $followsymlinks]);
This returns "true" if and only if there is a character device with
the given "path" name.
If the optional flag "followsymlinks" is true, then a symlink (or
chain of symlinks) that ends with a chardev also causes the
function to return true.
See also "$g->stat".
$flag = $g->is_chardev_opts ($path [, followsymlinks =>
$followsymlinks]);
This is an alias of "is_chardev".
$config = $g->is_config ();
This returns true iff this handle is being configured (in the
"CONFIG" state).
For more information on states, see guestfs(3).
$dirflag = $g->is_dir ($path [, followsymlinks => $followsymlinks]);
This returns "true" if and only if there is a directory with the
given "path" name. Note that it returns false for other objects
like files.
If the optional flag "followsymlinks" is true, then a symlink (or
chain of symlinks) that ends with a directory also causes the
function to return true.
See also "$g->stat".
$dirflag = $g->is_dir_opts ($path [, followsymlinks =>
$followsymlinks]);
This is an alias of "is_dir".
$flag = $g->is_fifo ($path [, followsymlinks => $followsymlinks]);
This returns "true" if and only if there is a FIFO (named pipe)
with the given "path" name.
If the optional flag "followsymlinks" is true, then a symlink (or
chain of symlinks) that ends with a FIFO also causes the function
to return true.
See also "$g->stat".
$flag = $g->is_fifo_opts ($path [, followsymlinks => $followsymlinks]);
This is an alias of "is_fifo".
$fileflag = $g->is_file ($path [, followsymlinks => $followsymlinks]);
This returns "true" if and only if there is a regular file with the
given "path" name. Note that it returns false for other objects
like directories.
If the optional flag "followsymlinks" is true, then a symlink (or
chain of symlinks) that ends with a file also causes the function
to return true.
See also "$g->stat".
$fileflag = $g->is_file_opts ($path [, followsymlinks =>
$followsymlinks]);
This is an alias of "is_file".
$launching = $g->is_launching ();
This returns true iff this handle is launching the subprocess (in
the "LAUNCHING" state).
For more information on states, see guestfs(3).
$lvflag = $g->is_lv ($device);
This command tests whether "device" is a logical volume, and
returns true iff this is the case.
$ready = $g->is_ready ();
This returns true iff this handle is ready to accept commands (in
the "READY" state).
For more information on states, see guestfs(3).
$flag = $g->is_socket ($path [, followsymlinks => $followsymlinks]);
This returns "true" if and only if there is a Unix domain socket
with the given "path" name.
If the optional flag "followsymlinks" is true, then a symlink (or
chain of symlinks) that ends with a socket also causes the function
to return true.
See also "$g->stat".
$flag = $g->is_socket_opts ($path [, followsymlinks =>
$followsymlinks]);
This is an alias of "is_socket".
$flag = $g->is_symlink ($path);
This returns "true" if and only if there is a symbolic link with
the given "path" name.
See also "$g->stat".
$flag = $g->is_whole_device ($device);
This returns "true" if and only if "device" refers to a whole block
device. That is, not a partition or a logical device.
$zeroflag = $g->is_zero ($path);
This returns true iff the file exists and the file is empty or it
contains all zero bytes.
$zeroflag = $g->is_zero_device ($device);
This returns true iff the device exists and contains all zero
bytes.
Note that for large devices this can take a long time to run.
%isodata = $g->isoinfo ($isofile);
This is the same as "$g->isoinfo_device" except that it works for
an ISO file located inside some other mounted filesystem. Note
that in the common case where you have added an ISO file as a
libguestfs device, you would not call this. Instead you would call
"$g->isoinfo_device".
%isodata = $g->isoinfo_device ($device);
"device" is an ISO device. This returns a struct of information
read from the primary volume descriptor (the ISO equivalent of the
superblock) of the device.
Usually it is more efficient to use the isoinfo(1) command with the
-d option on the host to analyze ISO files, instead of going
through libguestfs.
For information on the primary volume descriptor fields, see
<http://wiki.osdev.org/ISO_9660#The_Primary_Volume_Descriptor>
$g->kill_subprocess ();
This kills the qemu subprocess.
Do not call this. See: "$g->shutdown" instead.
This function is deprecated. In new code, use the "shutdown" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->launch ();
Internally libguestfs is implemented by running a virtual machine
using qemu(1).
You should call this after configuring the handle (eg. adding
drives) but before performing any actions.
Do not call "$g->launch" twice on the same handle. Although it
will not give an error (for historical reasons), the precise
behaviour when you do this is not well defined. Handles are very
cheap to create, so create a new one for each launch.
$g->lchown ($owner, $group, $path);
Change the file owner to "owner" and group to "group". This is
like "$g->chown" but if "path" is a symlink then the link itself is
changed, not the target.
Only numeric uid and gid are supported. If you want to use names,
you will need to locate and parse the password file yourself
(Augeas support makes this relatively easy).
$g->ldmtool_create_all ();
This function scans all block devices looking for Windows dynamic
disk volumes and partitions, and creates devices for any that were
found.
Call "$g->list_ldm_volumes" and "$g->list_ldm_partitions" to return
all devices.
Note that you don't normally need to call this explicitly, since it
is done automatically at "$g->launch" time. However you might want
to call this function if you have hotplugged disks or have just
created a Windows dynamic disk.
@disks = $g->ldmtool_diskgroup_disks ($diskgroup);
Return the disks in a Windows dynamic disk group. The "diskgroup"
parameter should be the GUID of a disk group, one element from the
list returned by "$g->ldmtool_scan".
$name = $g->ldmtool_diskgroup_name ($diskgroup);
Return the name of a Windows dynamic disk group. The "diskgroup"
parameter should be the GUID of a disk group, one element from the
list returned by "$g->ldmtool_scan".
@volumes = $g->ldmtool_diskgroup_volumes ($diskgroup);
Return the volumes in a Windows dynamic disk group. The
"diskgroup" parameter should be the GUID of a disk group, one
element from the list returned by "$g->ldmtool_scan".
$g->ldmtool_remove_all ();
This is essentially the opposite of "$g->ldmtool_create_all". It
removes the device mapper mappings for all Windows dynamic disk
volumes
@guids = $g->ldmtool_scan ();
This function scans for Windows dynamic disks. It returns a list
of identifiers (GUIDs) for all disk groups that were found. These
identifiers can be passed to other "$g->ldmtool_*" functions.
This function scans all block devices. To scan a subset of block
devices, call "$g->ldmtool_scan_devices" instead.
@guids = $g->ldmtool_scan_devices (\@devices);
This function scans for Windows dynamic disks. It returns a list
of identifiers (GUIDs) for all disk groups that were found. These
identifiers can be passed to other "$g->ldmtool_*" functions.
The parameter "devices" is a list of block devices which are
scanned. If this list is empty, all block devices are scanned.
$hint = $g->ldmtool_volume_hint ($diskgroup, $volume);
Return the hint field of the volume named "volume" in the disk
group with GUID "diskgroup". This may not be defined, in which
case the empty string is returned. The hint field is often, though
not always, the name of a Windows drive, eg. "E:".
@partitions = $g->ldmtool_volume_partitions ($diskgroup, $volume);
Return the list of partitions in the volume named "volume" in the
disk group with GUID "diskgroup".
$voltype = $g->ldmtool_volume_type ($diskgroup, $volume);
Return the type of the volume named "volume" in the disk group with
GUID "diskgroup".
Possible volume types that can be returned here include: "simple",
"spanned", "striped", "mirrored", "raid5". Other types may also be
returned.
$xattr = $g->lgetxattr ($path, $name);
Get a single extended attribute from file "path" named "name". If
"path" is a symlink, then this call returns an extended attribute
from the symlink.
Normally it is better to get all extended attributes from a file in
one go by calling "$g->getxattrs". However some Linux filesystem
implementations are buggy and do not provide a way to list out
attributes. For these filesystems (notably ntfs-3g) you have to
know the names of the extended attributes you want in advance and
call this function.
Extended attribute values are blobs of binary data. If there is no
extended attribute named "name", this returns an error.
See also: "$g->lgetxattrs", "$g->getxattr", attr(5).
@xattrs = $g->lgetxattrs ($path);
This is the same as "$g->getxattrs", but if "path" is a symbolic
link, then it returns the extended attributes of the link itself.
@devices = $g->list_devices ();
List all the block devices.
The full block device names are returned, eg. "/dev/sda".
See also "$g->list_filesystems".
%labels = $g->list_disk_labels ();
If you add drives using the optional "label" parameter of
"$g->add_drive_opts", you can use this call to map between disk
labels, and raw block device and partition names (like "/dev/sda"
and "/dev/sda1").
This returns a hashtable, where keys are the disk labels (without
the "/dev/disk/guestfs" prefix), and the values are the full raw
block device and partition names (eg. "/dev/sda" and "/dev/sda1").
@devices = $g->list_dm_devices ();
List all device mapper devices.
The returned list contains "/dev/mapper/*" devices, eg. ones
created by a previous call to "$g->luks_open".
Device mapper devices which correspond to logical volumes are not
returned in this list. Call "$g->lvs" if you want to list logical
volumes.
%fses = $g->list_filesystems ();
This inspection command looks for filesystems on partitions, block
devices and logical volumes, returning a list of "mountables"
containing filesystems and their type.
The return value is a hash, where the keys are the devices
containing filesystems, and the values are the filesystem types.
For example:
"/dev/sda1" => "ntfs"
"/dev/sda2" => "ext2"
"/dev/vg_guest/lv_root" => "ext4"
"/dev/vg_guest/lv_swap" => "swap"
The key is not necessarily a block device. It may also be an opaque
'mountable' string which can be passed to "$g->mount".
The value can have the special value "unknown", meaning the content
of the device is undetermined or empty. "swap" means a Linux swap
partition.
This command runs other libguestfs commands, which might include
"$g->mount" and "$g->umount", and therefore you should use this
soon after launch and only when nothing is mounted.
Not all of the filesystems returned will be mountable. In
particular, swap partitions are returned in the list. Also this
command does not check that each filesystem found is valid and
mountable, and some filesystems might be mountable but require
special options. Filesystems may not all belong to a single
logical operating system (use "$g->inspect_os" to look for OSes).
@devices = $g->list_ldm_partitions ();
This function returns all Windows dynamic disk partitions that were
found at launch time. It returns a list of device names.
@devices = $g->list_ldm_volumes ();
This function returns all Windows dynamic disk volumes that were
found at launch time. It returns a list of device names.
@devices = $g->list_md_devices ();
List all Linux md devices.
@partitions = $g->list_partitions ();
List all the partitions detected on all block devices.
The full partition device names are returned, eg. "/dev/sda1"
This does not return logical volumes. For that you will need to
call "$g->lvs".
See also "$g->list_filesystems".
$listing = $g->ll ($directory);
List the files in "directory" (relative to the root directory,
there is no cwd) in the format of 'ls -la'.
This command is mostly useful for interactive sessions. It is not
intended that you try to parse the output string.
$listing = $g->llz ($directory);
List the files in "directory" in the format of 'ls -laZ'.
This command is mostly useful for interactive sessions. It is not
intended that you try to parse the output string.
$g->ln ($target, $linkname);
This command creates a hard link using the "ln" command.
$g->ln_f ($target, $linkname);
This command creates a hard link using the "ln -f" command. The -f
option removes the link ("linkname") if it exists already.
$g->ln_s ($target, $linkname);
This command creates a symbolic link using the "ln -s" command.
$g->ln_sf ($target, $linkname);
This command creates a symbolic link using the "ln -sf" command,
The -f option removes the link ("linkname") if it exists already.
$g->lremovexattr ($xattr, $path);
This is the same as "$g->removexattr", but if "path" is a symbolic
link, then it removes an extended attribute of the link itself.
@listing = $g->ls ($directory);
List the files in "directory" (relative to the root directory,
there is no cwd). The '.' and '..' entries are not returned, but
hidden files are shown.
$g->ls0 ($dir, $filenames);
This specialized command is used to get a listing of the filenames
in the directory "dir". The list of filenames is written to the
local file "filenames" (on the host).
In the output file, the filenames are separated by "\0" characters.
"." and ".." are not returned. The filenames are not sorted.
$g->lsetxattr ($xattr, $val, $vallen, $path);
This is the same as "$g->setxattr", but if "path" is a symbolic
link, then it sets an extended attribute of the link itself.
%statbuf = $g->lstat ($path);
Returns file information for the given "path".
This is the same as "$g->stat" except that if "path" is a symbolic
link, then the link is stat-ed, not the file it refers to.
This is the same as the lstat(2) system call.
@statbufs = $g->lstatlist ($path, \@names);
This call allows you to perform the "$g->lstat" operation on
multiple files, where all files are in the directory "path".
"names" is the list of files from this directory.
On return you get a list of stat structs, with a one-to-one
correspondence to the "names" list. If any name did not exist or
could not be lstat'd, then the "ino" field of that structure is set
to "-1".
This call is intended for programs that want to efficiently list a
directory contents without making many round-trips. See also
"$g->lxattrlist" for a similarly efficient call for getting
extended attributes.
$g->luks_add_key ($device, $key, $newkey, $keyslot);
This command adds a new key on LUKS device "device". "key" is any
existing key, and is used to access the device. "newkey" is the
new key to add. "keyslot" is the key slot that will be replaced.
Note that if "keyslot" already contains a key, then this command
will fail. You have to use "$g->luks_kill_slot" first to remove
that key.
$g->luks_close ($device);
This closes a LUKS device that was created earlier by
"$g->luks_open" or "$g->luks_open_ro". The "device" parameter must
be the name of the LUKS mapping device (ie. "/dev/mapper/mapname")
and not the name of the underlying block device.
$g->luks_format ($device, $key, $keyslot);
This command erases existing data on "device" and formats the
device as a LUKS encrypted device. "key" is the initial key, which
is added to key slot "slot". (LUKS supports 8 key slots, numbered
0-7).
$g->luks_format_cipher ($device, $key, $keyslot, $cipher);
This command is the same as "$g->luks_format" but it also allows
you to set the "cipher" used.
$g->luks_kill_slot ($device, $key, $keyslot);
This command deletes the key in key slot "keyslot" from the
encrypted LUKS device "device". "key" must be one of the other
keys.
$g->luks_open ($device, $key, $mapname);
This command opens a block device which has been encrypted
according to the Linux Unified Key Setup (LUKS) standard.
"device" is the encrypted block device or partition.
The caller must supply one of the keys associated with the LUKS
block device, in the "key" parameter.
This creates a new block device called "/dev/mapper/mapname".
Reads and writes to this block device are decrypted from and
encrypted to the underlying "device" respectively.
If this block device contains LVM volume groups, then calling
"$g->vgscan" followed by "$g->vg_activate_all" will make them
visible.
Use "$g->list_dm_devices" to list all device mapper devices.
$g->luks_open_ro ($device, $key, $mapname);
This is the same as "$g->luks_open" except that a read-only mapping
is created.
$g->lvcreate ($logvol, $volgroup, $mbytes);
This creates an LVM logical volume called "logvol" on the volume
group "volgroup", with "size" megabytes.
$g->lvcreate_free ($logvol, $volgroup, $percent);
Create an LVM logical volume called "/dev/volgroup/logvol", using
approximately "percent" % of the free space remaining in the volume
group. Most usefully, when "percent" is 100 this will create the
largest possible LV.
$lv = $g->lvm_canonical_lv_name ($lvname);
This converts alternative naming schemes for LVs that you might
find to the canonical name. For example, "/dev/mapper/VG-LV" is
converted to "/dev/VG/LV".
This command returns an error if the "lvname" parameter does not
refer to a logical volume.
See also "$g->is_lv", "$g->canonical_device_name".
$g->lvm_clear_filter ();
This undoes the effect of "$g->lvm_set_filter". LVM will be able
to see every block device.
This command also clears the LVM cache and performs a volume group
scan.
$g->lvm_remove_all ();
This command removes all LVM logical volumes, volume groups and
physical volumes.
$g->lvm_set_filter (\@devices);
This sets the LVM device filter so that LVM will only be able to
"see" the block devices in the list "devices", and will ignore all
other attached block devices.
Where disk image(s) contain duplicate PVs or VGs, this command is
useful to get LVM to ignore the duplicates, otherwise LVM can get
confused. Note also there are two types of duplication possible:
either cloned PVs/VGs which have identical UUIDs; or VGs that are
not cloned but just happen to have the same name. In normal
operation you cannot create this situation, but you can do it
outside LVM, eg. by cloning disk images or by bit twiddling inside
the LVM metadata.
This command also clears the LVM cache and performs a volume group
scan.
You can filter whole block devices or individual partitions.
You cannot use this if any VG is currently in use (eg. contains a
mounted filesystem), even if you are not filtering out that VG.
$g->lvremove ($device);
Remove an LVM logical volume "device", where "device" is the path
to the LV, such as "/dev/VG/LV".
You can also remove all LVs in a volume group by specifying the VG
name, "/dev/VG".
$g->lvrename ($logvol, $newlogvol);
Rename a logical volume "logvol" with the new name "newlogvol".
$g->lvresize ($device, $mbytes);
This resizes (expands or shrinks) an existing LVM logical volume to
"mbytes". When reducing, data in the reduced part is lost.
$g->lvresize_free ($lv, $percent);
This expands an existing logical volume "lv" so that it fills "pc"%
of the remaining free space in the volume group. Commonly you
would call this with pc = 100 which expands the logical volume as
much as possible, using all remaining free space in the volume
group.
@logvols = $g->lvs ();
List all the logical volumes detected. This is the equivalent of
the lvs(8) command.
This returns a list of the logical volume device names (eg.
"/dev/VolGroup00/LogVol00").
See also "$g->lvs_full", "$g->list_filesystems".
@logvols = $g->lvs_full ();
List all the logical volumes detected. This is the equivalent of
the lvs(8) command. The "full" version includes all fields.
$uuid = $g->lvuuid ($device);
This command returns the UUID of the LVM LV "device".
@xattrs = $g->lxattrlist ($path, \@names);
This call allows you to get the extended attributes of multiple
files, where all files are in the directory "path". "names" is the
list of files from this directory.
On return you get a flat list of xattr structs which must be
interpreted sequentially. The first xattr struct always has a
zero-length "attrname". "attrval" in this struct is zero-length to
indicate there was an error doing "lgetxattr" for this file, or is
a C string which is a decimal number (the number of following
attributes for this file, which could be "0"). Then after the
first xattr struct are the zero or more attributes for the first
named file. This repeats for the second and subsequent files.
This call is intended for programs that want to efficiently list a
directory contents without making many round-trips. See also
"$g->lstatlist" for a similarly efficient call for getting standard
stats.
$disks = $g->max_disks ();
Return the maximum number of disks that may be added to a handle
(eg. by "$g->add_drive_opts" and similar calls).
This function was added in libguestfs 1.19.7. In previous versions
of libguestfs the limit was 25.
See "MAXIMUM NUMBER OF DISKS" in guestfs(3) for additional
information on this topic.
$g->md_create ($name, \@devices [, missingbitmap => $missingbitmap] [,
nrdevices => $nrdevices] [, spare => $spare] [, chunk => $chunk] [,
level => $level]);
Create a Linux md (RAID) device named "name" on the devices in the
list "devices".
The optional parameters are:
"missingbitmap"
A bitmap of missing devices. If a bit is set it means that a
missing device is added to the array. The least significant
bit corresponds to the first device in the array.
As examples:
If "devices = ["/dev/sda"]" and "missingbitmap = 0x1" then the
resulting array would be "[<missing>, "/dev/sda"]".
If "devices = ["/dev/sda"]" and "missingbitmap = 0x2" then the
resulting array would be "["/dev/sda", <missing>]".
This defaults to 0 (no missing devices).
The length of "devices" + the number of bits set in
"missingbitmap" must equal "nrdevices" + "spare".
"nrdevices"
The number of active RAID devices.
If not set, this defaults to the length of "devices" plus the
number of bits set in "missingbitmap".
"spare"
The number of spare devices.
If not set, this defaults to 0.
"chunk"
The chunk size in bytes.
"level"
The RAID level, which can be one of: linear, raid0, 0, stripe,
raid1, 1, mirror, raid4, 4, raid5, 5, raid6, 6, raid10, 10.
Some of these are synonymous, and more levels may be added in
future.
If not set, this defaults to "raid1".
%info = $g->md_detail ($md);
This command exposes the output of 'mdadm -DY <md>'. The following
fields are usually present in the returned hash. Other fields may
also be present.
"level"
The raid level of the MD device.
"devices"
The number of underlying devices in the MD device.
"metadata"
The metadata version used.
"uuid"
The UUID of the MD device.
"name"
The name of the MD device.
@devices = $g->md_stat ($md);
This call returns a list of the underlying devices which make up
the single software RAID array device "md".
To get a list of software RAID devices, call "$g->list_md_devices".
Each structure returned corresponds to one device along with
additional status information:
"mdstat_device"
The name of the underlying device.
"mdstat_index"
The index of this device within the array.
"mdstat_flags"
Flags associated with this device. This is a string containing
(in no specific order) zero or more of the following flags:
"W" write-mostly
"F" device is faulty
"S" device is a RAID spare
"R" replacement
$g->md_stop ($md);
This command deactivates the MD array named "md". The device is
stopped, but it is not destroyed or zeroed.
$g->mkdir ($path);
Create a directory named "path".
$g->mkdir_mode ($path, $mode);
This command creates a directory, setting the initial permissions
of the directory to "mode".
For common Linux filesystems, the actual mode which is set will be
"mode & ~umask & 01777". Non-native-Linux filesystems may
interpret the mode in other ways.
See also "$g->mkdir", "$g->umask"
$g->mkdir_p ($path);
Create a directory named "path", creating any parent directories as
necessary. This is like the "mkdir -p" shell command.
$dir = $g->mkdtemp ($tmpl);
This command creates a temporary directory. The "tmpl" parameter
should be a full pathname for the temporary directory name with the
final six characters being "XXXXXX".
For example: "/tmp/myprogXXXXXX" or "/Temp/myprogXXXXXX", the
second one being suitable for Windows filesystems.
The name of the temporary directory that was created is returned.
The temporary directory is created with mode 0700 and is owned by
root.
The caller is responsible for deleting the temporary directory and
its contents after use.
See also: mkdtemp(3)
$g->mke2fs ($device [, blockscount => $blockscount] [, blocksize =>
$blocksize] [, fragsize => $fragsize] [, blockspergroup =>
$blockspergroup] [, numberofgroups => $numberofgroups] [, bytesperinode
=> $bytesperinode] [, inodesize => $inodesize] [, journalsize =>
$journalsize] [, numberofinodes => $numberofinodes] [, stridesize =>
$stridesize] [, stripewidth => $stripewidth] [, maxonlineresize =>
$maxonlineresize] [, reservedblockspercentage =>
$reservedblockspercentage] [, mmpupdateinterval => $mmpupdateinterval]
[, journaldevice => $journaldevice] [, label => $label] [,
lastmounteddir => $lastmounteddir] [, creatoros => $creatoros] [,
fstype => $fstype] [, usagetype => $usagetype] [, uuid => $uuid] [,
forcecreate => $forcecreate] [, writesbandgrouponly =>
$writesbandgrouponly] [, lazyitableinit => $lazyitableinit] [,
lazyjournalinit => $lazyjournalinit] [, testfs => $testfs] [, discard
=> $discard] [, quotatype => $quotatype] [, extent => $extent] [,
filetype => $filetype] [, flexbg => $flexbg] [, hasjournal =>
$hasjournal] [, journaldev => $journaldev] [, largefile => $largefile]
[, quota => $quota] [, resizeinode => $resizeinode] [, sparsesuper =>
$sparsesuper] [, uninitbg => $uninitbg]);
"mke2fs" is used to create an ext2, ext3, or ext4 filesystem on
"device".
The optional "blockscount" is the size of the filesystem in blocks.
If omitted it defaults to the size of "device". Note if the
filesystem is too small to contain a journal, "mke2fs" will
silently create an ext2 filesystem instead.
$g->mke2fs_J ($fstype, $blocksize, $device, $journal);
This creates an ext2/3/4 filesystem on "device" with an external
journal on "journal". It is equivalent to the command:
mke2fs -t fstype -b blocksize -J device=<journal> <device>
See also "$g->mke2journal".
This function is deprecated. In new code, use the "mke2fs" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->mke2fs_JL ($fstype, $blocksize, $device, $label);
This creates an ext2/3/4 filesystem on "device" with an external
journal on the journal labeled "label".
See also "$g->mke2journal_L".
This function is deprecated. In new code, use the "mke2fs" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->mke2fs_JU ($fstype, $blocksize, $device, $uuid);
This creates an ext2/3/4 filesystem on "device" with an external
journal on the journal with UUID "uuid".
See also "$g->mke2journal_U".
This function is deprecated. In new code, use the "mke2fs" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->mke2journal ($blocksize, $device);
This creates an ext2 external journal on "device". It is
equivalent to the command:
mke2fs -O journal_dev -b blocksize device
This function is deprecated. In new code, use the "mke2fs" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->mke2journal_L ($blocksize, $label, $device);
This creates an ext2 external journal on "device" with label
"label".
This function is deprecated. In new code, use the "mke2fs" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->mke2journal_U ($blocksize, $uuid, $device);
This creates an ext2 external journal on "device" with UUID "uuid".
This function is deprecated. In new code, use the "mke2fs" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->mkfifo ($mode, $path);
This call creates a FIFO (named pipe) called "path" with mode
"mode". It is just a convenient wrapper around "$g->mknod".
The mode actually set is affected by the umask.
$g->mkfs ($fstype, $device [, blocksize => $blocksize] [, features =>
$features] [, inode => $inode] [, sectorsize => $sectorsize]);
This function creates a filesystem on "device". The filesystem
type is "fstype", for example "ext3".
The optional arguments are:
"blocksize"
The filesystem block size. Supported block sizes depend on the
filesystem type, but typically they are 1024, 2048 or 4096 for
Linux ext2/3 filesystems.
For VFAT and NTFS the "blocksize" parameter is treated as the
requested cluster size.
For UFS block sizes, please see mkfs.ufs(8).
"features"
This passes the -O parameter to the external mkfs program.
For certain filesystem types, this allows extra filesystem
features to be selected. See mke2fs(8) and mkfs.ufs(8) for
more details.
You cannot use this optional parameter with the "gfs" or "gfs2"
filesystem type.
"inode"
This passes the -I parameter to the external mke2fs(8) program
which sets the inode size (only for ext2/3/4 filesystems at
present).
"sectorsize"
This passes the -S parameter to external mkfs.ufs(8) program,
which sets sector size for ufs filesystem.
$g->mkfs_opts ($fstype, $device [, blocksize => $blocksize] [, features
=> $features] [, inode => $inode] [, sectorsize => $sectorsize]);
This is an alias of "mkfs".
$g->mkfs_b ($fstype, $blocksize, $device);
This call is similar to "$g->mkfs", but it allows you to control
the block size of the resulting filesystem. Supported block sizes
depend on the filesystem type, but typically they are 1024, 2048 or
4096 only.
For VFAT and NTFS the "blocksize" parameter is treated as the
requested cluster size.
This function is deprecated. In new code, use the "mkfs" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->mkfs_btrfs (\@devices [, allocstart => $allocstart] [, bytecount =>
$bytecount] [, datatype => $datatype] [, leafsize => $leafsize] [,
label => $label] [, metadata => $metadata] [, nodesize => $nodesize] [,
sectorsize => $sectorsize]);
Create a btrfs filesystem, allowing all configurables to be set.
For more information on the optional arguments, see mkfs.btrfs(8).
Since btrfs filesystems can span multiple devices, this takes a
non-empty list of devices.
To create general filesystems, use "$g->mkfs".
$g->mklost_and_found ($mountpoint);
Make the "lost+found" directory, normally in the root directory of
an ext2/3/4 filesystem. "mountpoint" is the directory under which
we try to create the "lost+found" directory.
$g->mkmountpoint ($exemptpath);
"$g->mkmountpoint" and "$g->rmmountpoint" are specialized calls
that can be used to create extra mountpoints before mounting the
first filesystem.
These calls are only necessary in some very limited circumstances,
mainly the case where you want to mount a mix of unrelated and/or
read-only filesystems together.
For example, live CDs often contain a "Russian doll" nest of
filesystems, an ISO outer layer, with a squashfs image inside, with
an ext2/3 image inside that. You can unpack this as follows in
guestfish:
add-ro Fedora-11-i686-Live.iso
run
mkmountpoint /cd
mkmountpoint /sqsh
mkmountpoint /ext3fs
mount /dev/sda /cd
mount-loop /cd/LiveOS/squashfs.img /sqsh
mount-loop /sqsh/LiveOS/ext3fs.img /ext3fs
The inner filesystem is now unpacked under the /ext3fs mountpoint.
"$g->mkmountpoint" is not compatible with "$g->umount_all". You
may get unexpected errors if you try to mix these calls. It is
safest to manually unmount filesystems and remove mountpoints after
use.
"$g->umount_all" unmounts filesystems by sorting the paths longest
first, so for this to work for manual mountpoints, you must ensure
that the innermost mountpoints have the longest pathnames, as in
the example code above.
For more details see
<https://bugzilla.redhat.com/show_bug.cgi?id=599503>
Autosync [see "$g->set_autosync", this is set by default on
handles] can cause "$g->umount_all" to be called when the handle is
closed which can also trigger these issues.
$g->mknod ($mode, $devmajor, $devminor, $path);
This call creates block or character special devices, or named
pipes (FIFOs).
The "mode" parameter should be the mode, using the standard
constants. "devmajor" and "devminor" are the device major and
minor numbers, only used when creating block and character special
devices.
Note that, just like mknod(2), the mode must be bitwise OR'd with
S_IFBLK, S_IFCHR, S_IFIFO or S_IFSOCK (otherwise this call just
creates a regular file). These constants are available in the
standard Linux header files, or you can use "$g->mknod_b",
"$g->mknod_c" or "$g->mkfifo" which are wrappers around this
command which bitwise OR in the appropriate constant for you.
The mode actually set is affected by the umask.
$g->mknod_b ($mode, $devmajor, $devminor, $path);
This call creates a block device node called "path" with mode
"mode" and device major/minor "devmajor" and "devminor". It is
just a convenient wrapper around "$g->mknod".
The mode actually set is affected by the umask.
$g->mknod_c ($mode, $devmajor, $devminor, $path);
This call creates a char device node called "path" with mode "mode"
and device major/minor "devmajor" and "devminor". It is just a
convenient wrapper around "$g->mknod".
The mode actually set is affected by the umask.
$g->mkswap ($device [, label => $label] [, uuid => $uuid]);
Create a Linux swap partition on "device".
The option arguments "label" and "uuid" allow you to set the label
and/or UUID of the new swap partition.
$g->mkswap_opts ($device [, label => $label] [, uuid => $uuid]);
This is an alias of "mkswap".
$g->mkswap_L ($label, $device);
Create a swap partition on "device" with label "label".
Note that you cannot attach a swap label to a block device (eg.
"/dev/sda"), just to a partition. This appears to be a limitation
of the kernel or swap tools.
This function is deprecated. In new code, use the "mkswap" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->mkswap_U ($uuid, $device);
Create a swap partition on "device" with UUID "uuid".
This function is deprecated. In new code, use the "mkswap" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->mkswap_file ($path);
Create a swap file.
This command just writes a swap file signature to an existing file.
To create the file itself, use something like "$g->fallocate".
$path = $g->mktemp ($tmpl [, suffix => $suffix]);
This command creates a temporary file. The "tmpl" parameter should
be a full pathname for the temporary directory name with the final
six characters being "XXXXXX".
For example: "/tmp/myprogXXXXXX" or "/Temp/myprogXXXXXX", the
second one being suitable for Windows filesystems.
The name of the temporary file that was created is returned.
The temporary file is created with mode 0600 and is owned by root.
The caller is responsible for deleting the temporary file after
use.
If the optional "suffix" parameter is given, then the suffix (eg.
".txt") is appended to the temporary name.
See also: "$g->mkdtemp".
$g->modprobe ($modulename);
This loads a kernel module in the appliance.
The kernel module must have been whitelisted when libguestfs was
built (see "appliance/kmod.whitelist.in" in the source).
$g->mount ($mountable, $mountpoint);
Mount a guest disk at a position in the filesystem. Block devices
are named "/dev/sda", "/dev/sdb" and so on, as they were added to
the guest. If those block devices contain partitions, they will
have the usual names (eg. "/dev/sda1"). Also LVM
"/dev/VG/LV"-style names can be used, or 'mountable' strings
returned by "$g->list_filesystems" or
"$g->inspect_get_mountpoints".
The rules are the same as for mount(2): A filesystem must first be
mounted on "/" before others can be mounted. Other filesystems can
only be mounted on directories which already exist.
The mounted filesystem is writable, if we have sufficient
permissions on the underlying device.
Before libguestfs 1.13.16, this call implicitly added the options
"sync" and "noatime". The "sync" option greatly slowed writes and
caused many problems for users. If your program might need to work
with older versions of libguestfs, use "$g->mount_options" instead
(using an empty string for the first parameter if you don't want
any options).
$g->mount_local ($localmountpoint [, readonly => $readonly] [, options
=> $options] [, cachetimeout => $cachetimeout] [, debugcalls =>
$debugcalls]);
This call exports the libguestfs-accessible filesystem to a local
mountpoint (directory) called "localmountpoint". Ordinary reads
and writes to files and directories under "localmountpoint" are
redirected through libguestfs.
If the optional "readonly" flag is set to true, then writes to the
filesystem return error "EROFS".
"options" is a comma-separated list of mount options. See
guestmount(1) for some useful options.
"cachetimeout" sets the timeout (in seconds) for cached directory
entries. The default is 60 seconds. See guestmount(1) for further
information.
If "debugcalls" is set to true, then additional debugging
information is generated for every FUSE call.
When "$g->mount_local" returns, the filesystem is ready, but is not
processing requests (access to it will block). You have to call
"$g->mount_local_run" to run the main loop.
See "MOUNT LOCAL" in guestfs(3) for full documentation.
$g->mount_local_run ();
Run the main loop which translates kernel calls to libguestfs
calls.
This should only be called after "$g->mount_local" returns
successfully. The call will not return until the filesystem is
unmounted.
Note you must not make concurrent libguestfs calls on the same
handle from another thread.
You may call this from a different thread than the one which called
"$g->mount_local", subject to the usual rules for threads and
libguestfs (see "MULTIPLE HANDLES AND MULTIPLE THREADS" in
guestfs(3)).
See "MOUNT LOCAL" in guestfs(3) for full documentation.
$g->mount_loop ($file, $mountpoint);
This command lets you mount "file" (a filesystem image in a file)
on a mount point. It is entirely equivalent to the command "mount
-o loop file mountpoint".
$g->mount_options ($options, $mountable, $mountpoint);
This is the same as the "$g->mount" command, but it allows you to
set the mount options as for the mount(8)-o flag.
If the "options" parameter is an empty string, then no options are
passed (all options default to whatever the filesystem uses).
$g->mount_ro ($mountable, $mountpoint);
This is the same as the "$g->mount" command, but it mounts the
filesystem with the read-only (-o ro) flag.
$g->mount_vfs ($options, $vfstype, $mountable, $mountpoint);
This is the same as the "$g->mount" command, but it allows you to
set both the mount options and the vfstype as for the mount(8)-o
and -t flags.
%mps = $g->mountpoints ();
This call is similar to "$g->mounts". That call returns a list of
devices. This one returns a hash table (map) of device name to
directory where the device is mounted.
@devices = $g->mounts ();
This returns the list of currently mounted filesystems. It returns
the list of devices (eg. "/dev/sda1", "/dev/VG/LV").
Some internal mounts are not shown.
See also: "$g->mountpoints"
$g->mv ($src, $dest);
This moves a file from "src" to "dest" where "dest" is either a
destination filename or destination directory.
See also: "$g->rename".
$nrdisks = $g->nr_devices ();
This returns the number of whole block devices that were added.
This is the same as the number of devices that would be returned if
you called "$g->list_devices".
To find out the maximum number of devices that could be added, call
"$g->max_disks".
$status = $g->ntfs_3g_probe ($rw, $device);
This command runs the ntfs-3g.probe(8) command which probes an NTFS
"device" for mountability. (Not all NTFS volumes can be mounted
read-write, and some cannot be mounted at all).
"rw" is a boolean flag. Set it to true if you want to test if the
volume can be mounted read-write. Set it to false if you want to
test if the volume can be mounted read-only.
The return value is an integer which 0 if the operation would
succeed, or some non-zero value documented in the ntfs-3g.probe(8)
manual page.
$g->ntfsclone_in ($backupfile, $device);
Restore the "backupfile" (from a previous call to
"$g->ntfsclone_out") to "device", overwriting any existing contents
of this device.
$g->ntfsclone_out ($device, $backupfile [, metadataonly =>
$metadataonly] [, rescue => $rescue] [, ignorefscheck =>
$ignorefscheck] [, preservetimestamps => $preservetimestamps] [, force
=> $force]);
Stream the NTFS filesystem "device" to the local file "backupfile".
The format used for the backup file is a special format used by the
ntfsclone(8) tool.
If the optional "metadataonly" flag is true, then only the metadata
is saved, losing all the user data (this is useful for diagnosing
some filesystem problems).
The optional "rescue", "ignorefscheck", "preservetimestamps" and
"force" flags have precise meanings detailed in the ntfsclone(8)
man page.
Use "$g->ntfsclone_in" to restore the file back to a libguestfs
device.
$g->ntfsfix ($device [, clearbadsectors => $clearbadsectors]);
This command repairs some fundamental NTFS inconsistencies, resets
the NTFS journal file, and schedules an NTFS consistency check for
the first boot into Windows.
This is not an equivalent of Windows "chkdsk". It does not scan
the filesystem for inconsistencies.
The optional "clearbadsectors" flag clears the list of bad sectors.
This is useful after cloning a disk with bad sectors to a new disk.
$g->ntfsresize ($device [, size => $size] [, force => $force]);
This command resizes an NTFS filesystem, expanding or shrinking it
to the size of the underlying device.
The optional parameters are:
"size"
The new size (in bytes) of the filesystem. If omitted, the
filesystem is resized to fit the container (eg. partition).
"force"
If this option is true, then force the resize of the filesystem
even if the filesystem is marked as requiring a consistency
check.
After the resize operation, the filesystem is always marked as
requiring a consistency check (for safety). You have to boot
into Windows to perform this check and clear this condition.
If you don't set the "force" option then it is not possible to
call "$g->ntfsresize" multiple times on a single filesystem
without booting into Windows between each resize.
See also ntfsresize(8).
$g->ntfsresize_opts ($device [, size => $size] [, force => $force]);
This is an alias of "ntfsresize".
$g->ntfsresize_size ($device, $size);
This command is the same as "$g->ntfsresize" except that it allows
you to specify the new size (in bytes) explicitly.
This function is deprecated. In new code, use the "ntfsresize"
call instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->parse_environment ();
Parse the program's environment and set flags in the handle
accordingly. For example if "LIBGUESTFS_DEBUG=1" then the
'verbose' flag is set in the handle.
Most programs do not need to call this. It is done implicitly when
you call "$g->create".
See "ENVIRONMENT VARIABLES" in guestfs(3) for a list of environment
variables that can affect libguestfs handles. See also
"guestfs_create_flags" in guestfs(3), and
"$g->parse_environment_list".
$g->parse_environment_list (\@environment);
Parse the list of strings in the argument "environment" and set
flags in the handle accordingly. For example if
"LIBGUESTFS_DEBUG=1" is a string in the list, then the 'verbose'
flag is set in the handle.
This is the same as "$g->parse_environment" except that it parses
an explicit list of strings instead of the program's environment.
$g->part_add ($device, $prlogex, $startsect, $endsect);
This command adds a partition to "device". If there is no
partition table on the device, call "$g->part_init" first.
The "prlogex" parameter is the type of partition. Normally you
should pass "p" or "primary" here, but MBR partition tables also
support "l" (or "logical") and "e" (or "extended") partition types.
"startsect" and "endsect" are the start and end of the partition in
sectors. "endsect" may be negative, which means it counts
backwards from the end of the disk ("-1" is the last sector).
Creating a partition which covers the whole disk is not so easy.
Use "$g->part_disk" to do that.
$g->part_del ($device, $partnum);
This command deletes the partition numbered "partnum" on "device".
Note that in the case of MBR partitioning, deleting an extended
partition also deletes any logical partitions it contains.
$g->part_disk ($device, $parttype);
This command is simply a combination of "$g->part_init" followed by
"$g->part_add" to create a single primary partition covering the
whole disk.
"parttype" is the partition table type, usually "mbr" or "gpt", but
other possible values are described in "$g->part_init".
$bootable = $g->part_get_bootable ($device, $partnum);
This command returns true if the partition "partnum" on "device"
has the bootable flag set.
See also "$g->part_set_bootable".
$guid = $g->part_get_gpt_type ($device, $partnum);
Return the type GUID of numbered GPT partition "partnum". For MBR
partitions, return an appropriate GUID corresponding to the MBR
type. Behaviour is undefined for other partition types.
$idbyte = $g->part_get_mbr_id ($device, $partnum);
Returns the MBR type byte (also known as the ID byte) from the
numbered partition "partnum".
Note that only MBR (old DOS-style) partitions have type bytes. You
will get undefined results for other partition table types (see
"$g->part_get_parttype").
$parttype = $g->part_get_parttype ($device);
This command examines the partition table on "device" and returns
the partition table type (format) being used.
Common return values include: "msdos" (a DOS/Windows style MBR
partition table), "gpt" (a GPT/EFI-style partition table). Other
values are possible, although unusual. See "$g->part_init" for a
full list.
$g->part_init ($device, $parttype);
This creates an empty partition table on "device" of one of the
partition types listed below. Usually "parttype" should be either
"msdos" or "gpt" (for large disks).
Initially there are no partitions. Following this, you should call
"$g->part_add" for each partition required.
Possible values for "parttype" are:
efi
gpt Intel EFI / GPT partition table.
This is recommended for >= 2 TB partitions that will be
accessed from Linux and Intel-based Mac OS X. It also has
limited backwards compatibility with the "mbr" format.
mbr
msdos
The standard PC "Master Boot Record" (MBR) format used by MS-
DOS and Windows. This partition type will only work for device
sizes up to 2 TB. For large disks we recommend using "gpt".
Other partition table types that may work but are not supported
include:
aix AIX disk labels.
amiga
rdb Amiga "Rigid Disk Block" format.
bsd BSD disk labels.
dasd
DASD, used on IBM mainframes.
dvh MIPS/SGI volumes.
mac Old Mac partition format. Modern Macs use "gpt".
pc98
NEC PC-98 format, common in Japan apparently.
sun Sun disk labels.
@partitions = $g->part_list ($device);
This command parses the partition table on "device" and returns the
list of partitions found.
The fields in the returned structure are:
part_num
Partition number, counting from 1.
part_start
Start of the partition in bytes. To get sectors you have to
divide by the device's sector size, see "$g->blockdev_getss".
part_end
End of the partition in bytes.
part_size
Size of the partition in bytes.
$g->part_set_bootable ($device, $partnum, $bootable);
This sets the bootable flag on partition numbered "partnum" on
device "device". Note that partitions are numbered from 1.
The bootable flag is used by some operating systems (notably
Windows) to determine which partition to boot from. It is by no
means universally recognized.
$g->part_set_gpt_type ($device, $partnum, $guid);
Set the type GUID of numbered GPT partition "partnum" to "guid".
Return an error if the partition table of "device" isn't GPT, or if
"guid" is not a valid GUID.
See
<http://en.wikipedia.org/wiki/GUID_Partition_Table#Partition_type_GUIDs>
for a useful list of type GUIDs.
$g->part_set_mbr_id ($device, $partnum, $idbyte);
Sets the MBR type byte (also known as the ID byte) of the numbered
partition "partnum" to "idbyte". Note that the type bytes quoted
in most documentation are in fact hexadecimal numbers, but usually
documented without any leading "0x" which might be confusing.
Note that only MBR (old DOS-style) partitions have type bytes. You
will get undefined results for other partition table types (see
"$g->part_get_parttype").
$g->part_set_name ($device, $partnum, $name);
This sets the partition name on partition numbered "partnum" on
device "device". Note that partitions are numbered from 1.
The partition name can only be set on certain types of partition
table. This works on "gpt" but not on "mbr" partitions.
$device = $g->part_to_dev ($partition);
This function takes a partition name (eg. "/dev/sdb1") and removes
the partition number, returning the device name (eg. "/dev/sdb").
The named partition must exist, for example as a string returned
from "$g->list_partitions".
See also "$g->part_to_partnum", "$g->device_index".
$partnum = $g->part_to_partnum ($partition);
This function takes a partition name (eg. "/dev/sdb1") and returns
the partition number (eg. 1).
The named partition must exist, for example as a string returned
from "$g->list_partitions".
See also "$g->part_to_dev".
$g->ping_daemon ();
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.
$content = $g->pread ($path, $count, $offset);
This command lets you read part of a file. It reads "count" bytes
of the file, starting at "offset", from file "path".
This may read fewer bytes than requested. For further details see
the pread(2) system call.
See also "$g->pwrite", "$g->pread_device".
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
$content = $g->pread_device ($device, $count, $offset);
This command lets you read part of a block device. It reads
"count" bytes of "device", starting at "offset".
This may read fewer bytes than requested. For further details see
the pread(2) system call.
See also "$g->pread".
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
$g->pvchange_uuid ($device);
Generate a new random UUID for the physical volume "device".
$g->pvchange_uuid_all ();
Generate new random UUIDs for all physical volumes.
$g->pvcreate ($device);
This creates an LVM physical volume on the named "device", where
"device" should usually be a partition name such as "/dev/sda1".
$g->pvremove ($device);
This wipes a physical volume "device" so that LVM will no longer
recognise it.
The implementation uses the "pvremove" command which refuses to
wipe physical volumes that contain any volume groups, so you have
to remove those first.
$g->pvresize ($device);
This resizes (expands or shrinks) an existing LVM physical volume
to match the new size of the underlying device.
$g->pvresize_size ($device, $size);
This command is the same as "$g->pvresize" except that it allows
you to specify the new size (in bytes) explicitly.
@physvols = $g->pvs ();
List all the physical volumes detected. This is the equivalent of
the pvs(8) command.
This returns a list of just the device names that contain PVs (eg.
"/dev/sda2").
See also "$g->pvs_full".
@physvols = $g->pvs_full ();
List all the physical volumes detected. This is the equivalent of
the pvs(8) command. The "full" version includes all fields.
$uuid = $g->pvuuid ($device);
This command returns the UUID of the LVM PV "device".
$nbytes = $g->pwrite ($path, $content, $offset);
This command writes to part of a file. It writes the data buffer
"content" to the file "path" starting at offset "offset".
This command implements the pwrite(2) system call, and like that
system call it may not write the full data requested. The return
value is the number of bytes that were actually written to the
file. This could even be 0, although short writes are unlikely for
regular files in ordinary circumstances.
See also "$g->pread", "$g->pwrite_device".
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
$nbytes = $g->pwrite_device ($device, $content, $offset);
This command writes to part of a device. It writes the data buffer
"content" to "device" starting at offset "offset".
This command implements the pwrite(2) system call, and like that
system call it may not write the full data requested (although
short writes to disk devices and partitions are probably impossible
with standard Linux kernels).
See also "$g->pwrite".
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
$content = $g->read_file ($path);
This calls returns the contents of the file "path" as a buffer.
Unlike "$g->cat", this function can correctly handle files that
contain embedded ASCII NUL characters.
@lines = $g->read_lines ($path);
Return the contents of the file named "path".
The file contents are returned as a list of lines. Trailing "LF"
and "CRLF" character sequences are not returned.
Note that this function cannot correctly handle binary files
(specifically, files containing "\0" character which is treated as
end of string). For those you need to use the "$g->read_file"
function and split the buffer into lines yourself.
@entries = $g->readdir ($dir);
This returns the list of directory entries in directory "dir".
All entries in the directory are returned, including "." and "..".
The entries are not sorted, but returned in the same order as the
underlying filesystem.
Also this call returns basic file type information about each file.
The "ftyp" field will contain one of the following characters:
'b' Block special
'c' Char special
'd' Directory
'f' FIFO (named pipe)
'l' Symbolic link
'r' Regular file
's' Socket
'u' Unknown file type
'?' The readdir(3) call returned a "d_type" field with an
unexpected value
This function is primarily intended for use by programs. To get a
simple list of names, use "$g->ls". To get a printable directory
for human consumption, use "$g->ll".
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
$link = $g->readlink ($path);
This command reads the target of a symbolic link.
@links = $g->readlinklist ($path, \@names);
This call allows you to do a "readlink" operation on multiple
files, where all files are in the directory "path". "names" is the
list of files from this directory.
On return you get a list of strings, with a one-to-one
correspondence to the "names" list. Each string is the value of
the symbolic link.
If the readlink(2) operation fails on any name, then the
corresponding result string is the empty string "". However the
whole operation is completed even if there were readlink(2) errors,
and so you can call this function with names where you don't know
if they are symbolic links already (albeit slightly less
efficient).
This call is intended for programs that want to efficiently list a
directory contents without making many round-trips.
$rpath = $g->realpath ($path);
Return the canonicalized absolute pathname of "path". The returned
path has no ".", ".." or symbolic link path elements.
$g->remount ($mountpoint [, rw => $rw]);
This call allows you to change the "rw" (readonly/read-write) flag
on an already mounted filesystem at "mountpoint", converting a
readonly filesystem to be read-write, or vice-versa.
Note that at the moment you must supply the "optional" "rw"
parameter. In future we may allow other flags to be adjusted.
$g->remove_drive ($label);
This function is conceptually the opposite of "$g->add_drive_opts".
It removes the drive that was previously added with label "label".
Note that in order to remove drives, you have to add them with
labels (see the optional "label" argument to "$g->add_drive_opts").
If you didn't use a label, then they cannot be removed.
You can call this function before or after launching the handle.
If called after launch, if the backend supports it, we try to hot
unplug the drive: see "HOTPLUGGING" in guestfs(3). The disk must
not be in use (eg. mounted) when you do this. We try to detect if
the disk is in use and stop you from doing this.
$g->removexattr ($xattr, $path);
This call removes the extended attribute named "xattr" of the file
"path".
See also: "$g->lremovexattr", attr(5).
$g->rename ($oldpath, $newpath);
Rename a file to a new place on the same filesystem. This is the
same as the Linux rename(2) system call. In most cases you are
better to use "$g->mv" instead.
$g->resize2fs ($device);
This resizes an ext2, ext3 or ext4 filesystem to match the size of
the underlying device.
See also "RESIZE2FS ERRORS" in guestfs(3).
$g->resize2fs_M ($device);
This command is the same as "$g->resize2fs", but the filesystem is
resized to its minimum size. This works like the -M option to the
"resize2fs" command.
To get the resulting size of the filesystem you should call
"$g->tune2fs_l" and read the "Block size" and "Block count" values.
These two numbers, multiplied together, give the resulting size of
the minimal filesystem in bytes.
See also "RESIZE2FS ERRORS" in guestfs(3).
$g->resize2fs_size ($device, $size);
This command is the same as "$g->resize2fs" except that it allows
you to specify the new size (in bytes) explicitly.
See also "RESIZE2FS ERRORS" in guestfs(3).
$g->rm ($path);
Remove the single file "path".
$g->rm_f ($path);
Remove the file "path".
If the file doesn't exist, that error is ignored. (Other errors,
eg. I/O errors or bad paths, are not ignored)
This call cannot remove directories. Use "$g->rmdir" to remove an
empty directory, or "$g->rm_rf" to remove directories recursively.
$g->rm_rf ($path);
Remove the file or directory "path", recursively removing the
contents if its a directory. This is like the "rm -rf" shell
command.
$g->rmdir ($path);
Remove the single directory "path".
$g->rmmountpoint ($exemptpath);
This calls removes a mountpoint that was previously created with
"$g->mkmountpoint". See "$g->mkmountpoint" for full details.
$g->rsync ($src, $dest [, archive => $archive] [, deletedest =>
$deletedest]);
This call may be used to copy or synchronize two directories under
the same libguestfs handle. This uses the rsync(1) program which
uses a fast algorithm that avoids copying files unnecessarily.
"src" and "dest" are the source and destination directories. Files
are copied from "src" to "dest".
The optional arguments are:
"archive"
Turns on archive mode. This is the same as passing the
--archive flag to "rsync".
"deletedest"
Delete files at the destination that do not exist at the
source.
$g->rsync_in ($remote, $dest [, archive => $archive] [, deletedest =>
$deletedest]);
This call may be used to copy or synchronize the filesystem on the
host or on a remote computer with the filesystem within libguestfs.
This uses the rsync(1) program which uses a fast algorithm that
avoids copying files unnecessarily.
This call only works if the network is enabled. See
"$g->set_network" or the --network option to various tools like
guestfish(1).
Files are copied from the remote server and directory specified by
"remote" to the destination directory "dest".
The format of the remote server string is defined by rsync(1).
Note that there is no way to supply a password or passphrase so the
target must be set up not to require one.
The optional arguments are the same as those of "$g->rsync".
$g->rsync_out ($src, $remote [, archive => $archive] [, deletedest =>
$deletedest]);
This call may be used to copy or synchronize the filesystem within
libguestfs with a filesystem on the host or on a remote computer.
This uses the rsync(1) program which uses a fast algorithm that
avoids copying files unnecessarily.
This call only works if the network is enabled. See
"$g->set_network" or the --network option to various tools like
guestfish(1).
Files are copied from the source directory "src" to the remote
server and directory specified by "remote".
The format of the remote server string is defined by rsync(1).
Note that there is no way to supply a password or passphrase so the
target must be set up not to require one.
The optional arguments are the same as those of "$g->rsync".
Globbing does not happen on the "src" parameter. In programs which
use the API directly you have to expand wildcards yourself (see
"$g->glob_expand"). In guestfish you can use the "glob" command
(see "glob" in guestfish(1)), for example:
><fs> glob rsync-out /* rsync://remote/
$g->scrub_device ($device);
This command writes patterns over "device" to make data retrieval
more difficult.
It is an interface to the scrub(1) program. See that manual page
for more details.
$g->scrub_file ($file);
This command writes patterns over a file to make data retrieval
more difficult.
The file is removed after scrubbing.
It is an interface to the scrub(1) program. See that manual page
for more details.
$g->scrub_freespace ($dir);
This command creates the directory "dir" and then fills it with
files until the filesystem is full, and scrubs the files as for
"$g->scrub_file", and deletes them. The intention is to scrub any
free space on the partition containing "dir".
It is an interface to the scrub(1) program. See that manual page
for more details.
$g->set_append ($append);
This function is used to add additional options to the guest kernel
command line.
The default is "NULL" unless overridden by setting
"LIBGUESTFS_APPEND" environment variable.
Setting "append" to "NULL" means no additional options are passed
(libguestfs always adds a few of its own).
$g->set_attach_method ($backend);
Set the method that libguestfs uses to connect to the backend
guestfsd daemon.
See "BACKEND" in guestfs(3).
This function is deprecated. In new code, use the "set_backend"
call instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->set_autosync ($autosync);
If "autosync" is true, this enables autosync. Libguestfs will make
a best effort attempt to make filesystems consistent and
synchronized when the handle is closed (also if the program exits
without closing handles).
This is enabled by default (since libguestfs 1.5.24, previously it
was disabled by default).
$g->set_backend ($backend);
Set the method that libguestfs uses to connect to the backend
guestfsd daemon.
This handle property was previously called the "attach method".
See "BACKEND" in guestfs(3).
$g->set_cachedir ($cachedir);
Set the directory used by the handle to store the appliance cache,
when using a supermin appliance. The appliance is cached and
shared between all handles which have the same effective user ID.
The environment variables "LIBGUESTFS_CACHEDIR" and "TMPDIR"
control the default value: If "LIBGUESTFS_CACHEDIR" is set, then
that is the default. Else if "TMPDIR" is set, then that is the
default. Else "/var/tmp" is the default.
$g->set_direct ($direct);
If the direct appliance mode flag is enabled, then stdin and stdout
are passed directly through to the appliance once it is launched.
One consequence of this is that log messages aren't caught by the
library and handled by "$g->set_log_message_callback", but go
straight to stdout.
You probably don't want to use this unless you know what you are
doing.
The default is disabled.
$g->set_e2attrs ($file, $attrs [, clear => $clear]);
This sets or clears the file attributes "attrs" associated with the
inode "file".
"attrs" is a string of characters representing file attributes.
See "$g->get_e2attrs" for a list of possible attributes. Not all
attributes can be changed.
If optional boolean "clear" is not present or false, then the
"attrs" listed are set in the inode.
If "clear" is true, then the "attrs" listed are cleared in the
inode.
In both cases, other attributes not present in the "attrs" string
are left unchanged.
These attributes are only present when the file is located on an
ext2/3/4 filesystem. Using this call on other filesystem types
will result in an error.
$g->set_e2generation ($file, $generation);
This sets the ext2 file generation of a file.
See "$g->get_e2generation".
$g->set_e2label ($device, $label);
This sets the ext2/3/4 filesystem label of the filesystem on
"device" to "label". Filesystem labels are limited to 16
characters.
You can use either "$g->tune2fs_l" or "$g->get_e2label" to return
the existing label on a filesystem.
This function is deprecated. In new code, use the "set_label" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->set_e2uuid ($device, $uuid);
This sets the ext2/3/4 filesystem UUID of the filesystem on
"device" to "uuid". The format of the UUID and alternatives such
as "clear", "random" and "time" are described in the tune2fs(8)
manpage.
You can use "$g->vfs_uuid" to return the existing UUID of a
filesystem.
This function is deprecated. In new code, use the "set_uuid" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->set_label ($mountable, $label);
Set the filesystem label on "mountable" to "label".
Only some filesystem types support labels, and libguestfs supports
setting labels on only a subset of these.
ext2, ext3, ext4
Labels are limited to 16 bytes.
NTFS
Labels are limited to 128 unicode characters.
XFS The label is limited to 12 bytes. The filesystem must not be
mounted when trying to set the label.
btrfs
The label is limited to 256 bytes and some characters are not
allowed. Setting the label on a btrfs subvolume will set the
label on its parent filesystem. The filesystem must not be
mounted when trying to set the label.
To read the label on a filesystem, call "$g->vfs_label".
$g->set_libvirt_requested_credential ($index, $cred);
After requesting the "index"'th credential from the user, call this
function to pass the answer back to libvirt.
See "LIBVIRT AUTHENTICATION" in guestfs(3) for documentation and
example code.
$g->set_libvirt_supported_credentials (\@creds);
Call this function before setting an event handler for
"GUESTFS_EVENT_LIBVIRT_AUTH", to supply the list of credential
types that the program knows how to process.
The "creds" list must be a non-empty list of strings. Possible
strings are:
"username"
"authname"
"language"
"cnonce"
"passphrase"
"echoprompt"
"noechoprompt"
"realm"
"external"
See libvirt documentation for the meaning of these credential
types.
See "LIBVIRT AUTHENTICATION" in guestfs(3) for documentation and
example code.
$g->set_memsize ($memsize);
This sets the memory size in megabytes allocated to the qemu
subprocess. This only has any effect if called before
"$g->launch".
You can also change this by setting the environment variable
"LIBGUESTFS_MEMSIZE" before the handle is created.
For more information on the architecture of libguestfs, see
guestfs(3).
$g->set_network ($network);
If "network" is true, then the network is enabled in the libguestfs
appliance. The default is false.
This affects whether commands are able to access the network (see
"RUNNING COMMANDS" in guestfs(3)).
You must call this before calling "$g->launch", otherwise it has no
effect.
$g->set_path ($searchpath);
Set the path that libguestfs searches for kernel and initrd.img.
The default is "$libdir/guestfs" unless overridden by setting
"LIBGUESTFS_PATH" environment variable.
Setting "path" to "NULL" restores the default path.
$g->set_pgroup ($pgroup);
If "pgroup" is true, child processes are placed into their own
process group.
The practical upshot of this is that signals like "SIGINT" (from
users pressing "^C") won't be received by the child process.
The default for this flag is false, because usually you want "^C"
to kill the subprocess. Guestfish sets this flag to true when used
interactively, so that "^C" can cancel long-running commands
gracefully (see "$g->user_cancel").
$g->set_program ($program);
Set the program name. This is an informative string which the main
program may optionally set in the handle.
When the handle is created, the program name in the handle is set
to the basename from "argv[0]". If that was not possible, it is
set to the empty string (but never "NULL").
$g->set_qemu ($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 "LIBGUESTFS_QEMU"
environment variable.
Setting "qemu" to "NULL" restores the default qemu binary.
Note that you should call this function as early as possible after
creating the handle. This is because some pre-launch operations
depend on testing qemu features (by running "qemu -help"). If the
qemu binary changes, we don't retest features, and so you might see
inconsistent results. Using the environment variable
"LIBGUESTFS_QEMU" is safest of all since that picks the qemu binary
at the same time as the handle is created.
$g->set_recovery_proc ($recoveryproc);
If this is called with the parameter "false" then "$g->launch" does
not create a recovery process. The purpose of the recovery process
is to stop runaway qemu processes in the case where the main
program aborts abruptly.
This only has any effect if called before "$g->launch", and the
default is true.
About the only time when you would want to disable this is if the
main process will fork itself into the background ("daemonize"
itself). In this case the recovery process thinks that the main
program has disappeared and so kills qemu, which is not very
helpful.
$g->set_selinux ($selinux);
This sets the selinux flag that is passed to the appliance at boot
time. The default is "selinux=0" (disabled).
Note that if SELinux is enabled, it is always in Permissive mode
("enforcing=0").
For more information on the architecture of libguestfs, see
guestfs(3).
$g->set_smp ($smp);
Change the number of virtual CPUs assigned to the appliance. The
default is 1. Increasing this may improve performance, though
often it has no effect.
This function must be called before "$g->launch".
$g->set_tmpdir ($tmpdir);
Set the directory used by the handle to store temporary files.
The environment variables "LIBGUESTFS_TMPDIR" and "TMPDIR" control
the default value: If "LIBGUESTFS_TMPDIR" is set, then that is the
default. Else if "TMPDIR" is set, then that is the default. Else
"/tmp" is the default.
$g->set_trace ($trace);
If the command trace flag is set to 1, then libguestfs calls,
parameters and return values are traced.
If you want to trace C API calls into libguestfs (and other
libraries) then possibly a better way is to use the external
ltrace(1) command.
Command traces are disabled unless the environment variable
"LIBGUESTFS_TRACE" is defined and set to 1.
Trace messages are normally sent to "stderr", unless you register a
callback to send them somewhere else (see
"$g->set_event_callback").
$g->set_uuid ($device, $uuid);
Set the filesystem UIUD on "device" to "label".
Only some filesystem types support setting UUIDs.
To read the UUID on a filesystem, call "$g->vfs_uuid".
$g->set_verbose ($verbose);
If "verbose" is true, this turns on verbose messages.
Verbose messages are disabled unless the environment variable
"LIBGUESTFS_DEBUG" is defined and set to 1.
Verbose messages are normally sent to "stderr", unless you register
a callback to send them somewhere else (see
"$g->set_event_callback").
$g->setcon ($context);
This sets the SELinux security context of the daemon to the string
"context".
See the documentation about SELINUX in guestfs(3).
$g->setxattr ($xattr, $val, $vallen, $path);
This call sets the extended attribute named "xattr" of the file
"path" to the value "val" (of length "vallen"). The value is
arbitrary 8 bit data.
See also: "$g->lsetxattr", attr(5).
$g->sfdisk ($device, $cyls, $heads, $sectors, \@lines);
This is a direct interface to the sfdisk(8) program for creating
partitions on block devices.
"device" should be a block device, for example "/dev/sda".
"cyls", "heads" and "sectors" are the number of cylinders, heads
and sectors on the device, which are passed directly to sfdisk as
the -C, -H and -S parameters. If you pass 0 for any of these, then
the corresponding parameter is omitted. Usually for 'large' disks,
you can just pass 0 for these, but for small (floppy-sized) disks,
sfdisk (or rather, the kernel) cannot work out the right geometry
and you will need to tell it.
"lines" is a list of lines that we feed to "sfdisk". For more
information refer to the sfdisk(8) manpage.
To create a single partition occupying the whole disk, you would
pass "lines" as a single element list, when the single element
being the string "," (comma).
See also: "$g->sfdisk_l", "$g->sfdisk_N", "$g->part_init"
This function is deprecated. In new code, use the "part_add" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->sfdiskM ($device, \@lines);
This is a simplified interface to the "$g->sfdisk" command, where
partition sizes are specified in megabytes only (rounded to the
nearest cylinder) and you don't need to specify the cyls, heads and
sectors parameters which were rarely if ever used anyway.
See also: "$g->sfdisk", the sfdisk(8) manpage and "$g->part_disk"
This function is deprecated. In new code, use the "part_add" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->sfdisk_N ($device, $partnum, $cyls, $heads, $sectors, $line);
This runs sfdisk(8) option to modify just the single partition "n"
(note: "n" counts from 1).
For other parameters, see "$g->sfdisk". You should usually pass 0
for the cyls/heads/sectors parameters.
See also: "$g->part_add"
This function is deprecated. In new code, use the "part_add" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$partitions = $g->sfdisk_disk_geometry ($device);
This displays the disk geometry of "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 "$g->sfdisk_kernel_geometry").
The result is in human-readable format, and not designed to be
parsed.
$partitions = $g->sfdisk_kernel_geometry ($device);
This displays the kernel's idea of the geometry of "device".
The result is in human-readable format, and not designed to be
parsed.
$partitions = $g->sfdisk_l ($device);
This displays the partition table on "device", in the human-
readable output of the sfdisk(8) command. It is not intended to be
parsed.
See also: "$g->part_list"
This function is deprecated. In new code, use the "part_list" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$output = $g->sh ($command);
This call runs a command from the guest filesystem via the guest's
"/bin/sh".
This is like "$g->command", but passes the command to:
/bin/sh -c "command"
Depending on the guest's shell, this usually results in wildcards
being expanded, shell expressions being interpolated and so on.
All the provisos about "$g->command" apply to this call.
@lines = $g->sh_lines ($command);
This is the same as "$g->sh", but splits the result into a list of
lines.
See also: "$g->command_lines"
$g->shutdown ();
This is the opposite of "$g->launch". It performs an orderly
shutdown of the backend process(es). If the autosync flag is set
(which is the default) then the disk image is synchronized.
If the subprocess exits with an error then this function will
return an error, which should not be ignored (it may indicate that
the disk image could not be written out properly).
It is safe to call this multiple times. Extra calls are ignored.
This call does not close or free up the handle. You still need to
call "$g->close" afterwards.
"$g->close" will call this if you don't do it explicitly, but note
that any errors are ignored in that case.
$g->sleep ($secs);
Sleep for "secs" seconds.
%statbuf = $g->stat ($path);
Returns file information for the given "path".
This is the same as the stat(2) system call.
%statbuf = $g->statvfs ($path);
Returns file system statistics for any mounted file system. "path"
should be a file or directory in the mounted file system (typically
it is the mount point itself, but it doesn't need to be).
This is the same as the statvfs(2) system call.
@stringsout = $g->strings ($path);
This runs the strings(1) command on a file and returns the list of
printable strings found.
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
@stringsout = $g->strings_e ($encoding, $path);
This is like the "$g->strings" command, but allows you to specify
the encoding of strings that are looked for in the source file
"path".
Allowed encodings are:
s Single 7-bit-byte characters like ASCII and the ASCII-
compatible parts of ISO-8859-X (this is what "$g->strings"
uses).
S Single 8-bit-byte characters.
b 16-bit big endian strings such as those encoded in UTF-16BE or
UCS-2BE.
l (lower case letter L)
16-bit little endian such as UTF-16LE and UCS-2LE. This is
useful for examining binaries in Windows guests.
B 32-bit big endian such as UCS-4BE.
L 32-bit little endian such as UCS-4LE.
The returned strings are transcoded to UTF-8.
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
$g->swapoff_device ($device);
This command disables the libguestfs appliance swap device or
partition named "device". See "$g->swapon_device".
$g->swapoff_file ($file);
This command disables the libguestfs appliance swap on file.
$g->swapoff_label ($label);
This command disables the libguestfs appliance swap on labeled swap
partition.
$g->swapoff_uuid ($uuid);
This command disables the libguestfs appliance swap partition with
the given UUID.
$g->swapon_device ($device);
This command enables the libguestfs appliance to use the swap
device or partition named "device". The increased memory is made
available for all commands, for example those run using
"$g->command" or "$g->sh".
Note that you should not swap to existing guest swap partitions
unless you know what you are doing. They may contain hibernation
information, or other information that the guest doesn't want you
to trash. You also risk leaking information about the host to the
guest this way. Instead, attach a new host device to the guest and
swap on that.
$g->swapon_file ($file);
This command enables swap to a file. See "$g->swapon_device" for
other notes.
$g->swapon_label ($label);
This command enables swap to a labeled swap partition. See
"$g->swapon_device" for other notes.
$g->swapon_uuid ($uuid);
This command enables swap to a swap partition with the given UUID.
See "$g->swapon_device" for other notes.
$g->sync ();
This syncs the disk, so that any writes are flushed through to the
underlying disk image.
You should always call this if you have modified a disk image,
before closing the handle.
$g->syslinux ($device [, directory => $directory]);
Install the SYSLINUX bootloader on "device".
The device parameter must be either a whole disk formatted as a FAT
filesystem, or a partition formatted as a FAT filesystem. In the
latter case, the partition should be marked as "active"
("$g->part_set_bootable") and a Master Boot Record must be
installed (eg. using "$g->pwrite_device") on the first sector of
the whole disk. The SYSLINUX package comes with some suitable
Master Boot Records. See the syslinux(1) man page for further
information.
The optional arguments are:
"directory"
Install SYSLINUX in the named subdirectory, instead of in the
root directory of the FAT filesystem.
Additional configuration can be supplied to SYSLINUX by placing a
file called "syslinux.cfg" on the FAT filesystem, either in the
root directory, or under "directory" if that optional argument is
being used. For further information about the contents of this
file, see syslinux(1).
See also "$g->extlinux".
@lines = $g->tail ($path);
This command returns up to the last 10 lines of a file as a list of
strings.
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
@lines = $g->tail_n ($nrlines, $path);
If the parameter "nrlines" is a positive number, this returns the
last "nrlines" lines of the file "path".
If the parameter "nrlines" is a negative number, this returns lines
from the file "path", starting with the "-nrlines"th line.
If the parameter "nrlines" is zero, this returns an empty list.
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
$g->tar_in ($tarfile, $directory [, compress => $compress]);
This command uploads and unpacks local file "tarfile" into
"directory".
The optional "compress" flag controls compression. If not given,
then the input should be an uncompressed tar file. Otherwise one
of the following strings may be given to select the compression
type of the input file: "compress", "gzip", "bzip2", "xz", "lzop".
(Note that not all builds of libguestfs will support all of these
compression types).
$g->tar_in_opts ($tarfile, $directory [, compress => $compress]);
This is an alias of "tar_in".
$g->tar_out ($directory, $tarfile [, compress => $compress] [,
numericowner => $numericowner] [, excludes => $excludes]);
This command packs the contents of "directory" and downloads it to
local file "tarfile".
The optional "compress" flag controls compression. If not given,
then the output will be an uncompressed tar file. Otherwise one of
the following strings may be given to select the compression type
of the output file: "compress", "gzip", "bzip2", "xz", "lzop".
(Note that not all builds of libguestfs will support all of these
compression types).
The other optional arguments are:
"excludes"
A list of wildcards. Files are excluded if they match any of
the wildcards.
"numericowner"
If set to true, the output tar file will contain UID/GID
numbers instead of user/group names.
$g->tar_out_opts ($directory, $tarfile [, compress => $compress] [,
numericowner => $numericowner] [, excludes => $excludes]);
This is an alias of "tar_out".
$g->tgz_in ($tarball, $directory);
This command uploads and unpacks local file "tarball" (a gzip
compressed tar file) into "directory".
This function is deprecated. In new code, use the "tar_in" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->tgz_out ($directory, $tarball);
This command packs the contents of "directory" and downloads it to
local file "tarball".
This function is deprecated. In new code, use the "tar_out" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->touch ($path);
Touch acts like the touch(1) command. It can be used to update the
timestamps on a file, or, if the file does not exist, to create a
new zero-length file.
This command only works on regular files, and will fail on other
file types such as directories, symbolic links, block special etc.
$g->truncate ($path);
This command truncates "path" to a zero-length file. The file must
exist already.
$g->truncate_size ($path, $size);
This command truncates "path" to size "size" bytes. The file must
exist already.
If the current file size is less than "size" then the file is
extended to the required size with zero bytes. This creates a
sparse file (ie. disk blocks are not allocated for the file until
you write to it). To create a non-sparse file of zeroes, use
"$g->fallocate64" instead.
$g->tune2fs ($device [, force => $force] [, maxmountcount =>
$maxmountcount] [, mountcount => $mountcount] [, errorbehavior =>
$errorbehavior] [, group => $group] [, intervalbetweenchecks =>
$intervalbetweenchecks] [, reservedblockspercentage =>
$reservedblockspercentage] [, lastmounteddirectory =>
$lastmounteddirectory] [, reservedblockscount => $reservedblockscount]
[, user => $user]);
This call allows you to adjust various filesystem parameters of an
ext2/ext3/ext4 filesystem called "device".
The optional parameters are:
"force"
Force tune2fs to complete the operation even in the face of
errors. This is the same as the tune2fs "-f" option.
"maxmountcount"
Set the number of mounts after which the filesystem is checked
by e2fsck(8). If this is 0 then the number of mounts is
disregarded. This is the same as the tune2fs "-c" option.
"mountcount"
Set the number of times the filesystem has been mounted. This
is the same as the tune2fs "-C" option.
"errorbehavior"
Change the behavior of the kernel code when errors are
detected. Possible values currently are: "continue",
"remount-ro", "panic". In practice these options don't really
make any difference, particularly for write errors.
This is the same as the tune2fs "-e" option.
"group"
Set the group which can use reserved filesystem blocks. This
is the same as the tune2fs "-g" option except that it can only
be specified as a number.
"intervalbetweenchecks"
Adjust the maximal time between two filesystem checks (in
seconds). If the option is passed as 0 then time-dependent
checking is disabled.
This is the same as the tune2fs "-i" option.
"reservedblockspercentage"
Set the percentage of the filesystem which may only be
allocated by privileged processes. This is the same as the
tune2fs "-m" option.
"lastmounteddirectory"
Set the last mounted directory. This is the same as the
tune2fs "-M" option.
"reservedblockscount" Set the number of reserved filesystem blocks.
This is the same as the tune2fs "-r" option.
"user"
Set the user who can use the reserved filesystem blocks. This
is the same as the tune2fs "-u" option except that it can only
be specified as a number.
To get the current values of filesystem parameters, see
"$g->tune2fs_l". For precise details of how tune2fs works, see the
tune2fs(8) man page.
%superblock = $g->tune2fs_l ($device);
This returns the contents of the ext2, ext3 or ext4 filesystem
superblock on "device".
It is the same as running "tune2fs -l device". See tune2fs(8)
manpage for more details. The list of fields returned isn't
clearly defined, and depends on both the version of "tune2fs" that
libguestfs was built against, and the filesystem itself.
$g->txz_in ($tarball, $directory);
This command uploads and unpacks local file "tarball" (an xz
compressed tar file) into "directory".
This function is deprecated. In new code, use the "tar_in" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->txz_out ($directory, $tarball);
This command packs the contents of "directory" and downloads it to
local file "tarball" (as an xz compressed tar archive).
This function is deprecated. In new code, use the "tar_out" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$oldmask = $g->umask ($mask);
This function sets the mask used for creating new files and device
nodes to "mask & 0777".
Typical umask values would be 022 which creates new files with
permissions like "-rw-r--r--" or "-rwxr-xr-x", and 002 which
creates new files with permissions like "-rw-rw-r--" or
"-rwxrwxr-x".
The default umask is 022. This is important because it means that
directories and device nodes will be created with 0644 or 0755 mode
even if you specify 0777.
See also "$g->get_umask", umask(2), "$g->mknod", "$g->mkdir".
This call returns the previous umask.
$g->umount ($pathordevice [, force => $force] [, lazyunmount =>
$lazyunmount]);
This unmounts the given filesystem. The filesystem may be
specified either by its mountpoint (path) or the device which
contains the filesystem.
$g->umount_opts ($pathordevice [, force => $force] [, lazyunmount =>
$lazyunmount]);
This is an alias of "umount".
$g->umount_all ();
This unmounts all mounted filesystems.
Some internal mounts are not unmounted by this call.
$g->umount_local ([retry => $retry]);
If libguestfs is exporting the filesystem on a local mountpoint,
then this unmounts it.
See "MOUNT LOCAL" in guestfs(3) for full documentation.
$g->upload ($filename, $remotefilename);
Upload local file "filename" to "remotefilename" on the filesystem.
"filename" can also be a named pipe.
See also "$g->download".
$g->upload_offset ($filename, $remotefilename, $offset);
Upload local file "filename" to "remotefilename" on the filesystem.
"remotefilename" is overwritten starting at the byte "offset"
specified. The intention is to overwrite parts of existing files
or devices, although if a non-existant file is specified then it is
created with a "hole" before "offset". The size of the data
written is implicit in the size of the source "filename".
Note that there is no limit on the amount of data that can be
uploaded with this call, unlike with "$g->pwrite", and this call
always writes the full amount unless an error occurs.
See also "$g->upload", "$g->pwrite".
$g->user_cancel ();
This function cancels the current upload or download operation.
Unlike most other libguestfs calls, this function is signal safe
and thread safe. You can call it from a signal handler or from
another thread, without needing to do any locking.
The transfer that was in progress (if there is one) will stop
shortly afterwards, and will return an error. The errno (see
"guestfs_last_errno") is set to "EINTR", so you can test for this
to find out if the operation was cancelled or failed because of
another error.
No cleanup is performed: for example, if a file was being uploaded
then after cancellation there may be a partially uploaded file. It
is the caller's responsibility to clean up if necessary.
There are two common places that you might call "$g->user_cancel":
In an interactive text-based program, you might call it from a
"SIGINT" signal handler so that pressing "^C" cancels the current
operation. (You also need to call "guestfs_set_pgroup" so that
child processes don't receive the "^C" signal).
In a graphical program, when the main thread is displaying a
progress bar with a cancel button, wire up the cancel button to
call this function.
$g->utimens ($path, $atsecs, $atnsecs, $mtsecs, $mtnsecs);
This command sets the timestamps of a file with nanosecond
precision.
"atsecs, atnsecs" are the last access time (atime) in secs and
nanoseconds from the epoch.
"mtsecs, mtnsecs" are the last modification time (mtime) in secs
and nanoseconds from the epoch.
If the *nsecs field contains the special value "-1" then the
corresponding timestamp is set to the current time. (The *secs
field is ignored in this case).
If the *nsecs field contains the special value "-2" then the
corresponding timestamp is left unchanged. (The *secs field is
ignored in this case).
%uts = $g->utsname ();
This returns the kernel version of the appliance, where this is
available. This information is only useful for debugging. Nothing
in the returned structure is defined by the API.
%version = $g->version ();
Return the libguestfs version number that the program is linked
against.
Note that because of dynamic linking this is not necessarily the
version of libguestfs that you compiled against. You can compile
the program, and then at runtime dynamically link against a
completely different "libguestfs.so" library.
This call was added in version 1.0.58. In previous versions of
libguestfs there was no way to get the version number. From C code
you can use dynamic linker functions to find out if this symbol
exists (if it doesn't, then it's an earlier version).
The call returns a structure with four elements. The first three
("major", "minor" and "release") are numbers and correspond to the
usual version triplet. The fourth element ("extra") is a string
and is normally empty, but may be used for distro-specific
information.
To construct the original version string:
"$major.$minor.$release$extra"
See also: "LIBGUESTFS VERSION NUMBERS" in guestfs(3).
Note: Don't use this call to test for availability of features. In
enterprise distributions we backport features from later versions
into earlier versions, making this an unreliable way to test for
features. Use "$g->available" or "$g->feature_available" instead.
$label = $g->vfs_label ($mountable);
This returns the label of the filesystem on "mountable".
If the filesystem is unlabeled, this returns the empty string.
To find a filesystem from the label, use "$g->findfs_label".
$fstype = $g->vfs_type ($mountable);
This command gets the filesystem type corresponding to the
filesystem on "mountable".
For most filesystems, the result is the name of the Linux VFS
module which would be used to mount this filesystem if you mounted
it without specifying the filesystem type. For example a string
such as "ext3" or "ntfs".
$uuid = $g->vfs_uuid ($mountable);
This returns the filesystem UUID of the filesystem on "mountable".
If the filesystem does not have a UUID, this returns the empty
string.
To find a filesystem from the UUID, use "$g->findfs_uuid".
$g->vg_activate ($activate, \@volgroups);
This command activates or (if "activate" is false) deactivates all
logical volumes in the listed volume groups "volgroups".
This command is the same as running "vgchange -a y|n volgroups..."
Note that if "volgroups" is an empty list then all volume groups
are activated or deactivated.
$g->vg_activate_all ($activate);
This command activates or (if "activate" is false) deactivates all
logical volumes in all volume groups.
This command is the same as running "vgchange -a y|n"
$g->vgchange_uuid ($vg);
Generate a new random UUID for the volume group "vg".
$g->vgchange_uuid_all ();
Generate new random UUIDs for all volume groups.
$g->vgcreate ($volgroup, \@physvols);
This creates an LVM volume group called "volgroup" from the non-
empty list of physical volumes "physvols".
@uuids = $g->vglvuuids ($vgname);
Given a VG called "vgname", this returns the UUIDs of all the
logical volumes created in this volume group.
You can use this along with "$g->lvs" and "$g->lvuuid" calls to
associate logical volumes and volume groups.
See also "$g->vgpvuuids".
$metadata = $g->vgmeta ($vgname);
"vgname" is an LVM volume group. This command examines the volume
group and returns its metadata.
Note that the metadata is an internal structure used by LVM,
subject to change at any time, and is provided for information
only.
@uuids = $g->vgpvuuids ($vgname);
Given a VG called "vgname", this returns the UUIDs of all the
physical volumes that this volume group resides on.
You can use this along with "$g->pvs" and "$g->pvuuid" calls to
associate physical volumes and volume groups.
See also "$g->vglvuuids".
$g->vgremove ($vgname);
Remove an LVM volume group "vgname", (for example "VG").
This also forcibly removes all logical volumes in the volume group
(if any).
$g->vgrename ($volgroup, $newvolgroup);
Rename a volume group "volgroup" with the new name "newvolgroup".
@volgroups = $g->vgs ();
List all the volumes groups detected. This is the equivalent of
the vgs(8) command.
This returns a list of just the volume group names that were
detected (eg. "VolGroup00").
See also "$g->vgs_full".
@volgroups = $g->vgs_full ();
List all the volumes groups detected. This is the equivalent of
the vgs(8) command. The "full" version includes all fields.
$g->vgscan ();
This rescans all block devices and rebuilds the list of LVM
physical volumes, volume groups and logical volumes.
$uuid = $g->vguuid ($vgname);
This command returns the UUID of the LVM VG named "vgname".
$g->wait_ready ();
This function is a no op.
In versions of the API < 1.0.71 you had to call this function just
after calling "$g->launch" to wait for the launch to complete.
However this is no longer necessary because "$g->launch" now does
the waiting.
If you see any calls to this function in code then you can just
remove them, unless you want to retain compatibility with older
versions of the API.
This function is deprecated. In new code, use the "launch" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$chars = $g->wc_c ($path);
This command counts the characters in a file, using the "wc -c"
external command.
$lines = $g->wc_l ($path);
This command counts the lines in a file, using the "wc -l" external
command.
$words = $g->wc_w ($path);
This command counts the words in a file, using the "wc -w" external
command.
$g->wipefs ($device);
This command erases filesystem or RAID signatures from the
specified "device" to make the filesystem invisible to libblkid.
This does not erase the filesystem itself nor any other data from
the "device".
Compare with "$g->zero" which zeroes the first few blocks of a
device.
$g->write ($path, $content);
This call creates a file called "path". The content of the file is
the string "content" (which can contain any 8 bit data).
See also "$g->write_append".
$g->write_append ($path, $content);
This call appends "content" to the end of file "path". If "path"
does not exist, then a new file is created.
See also "$g->write".
$g->write_file ($path, $content, $size);
This call creates a file called "path". The contents of the file
is the string "content" (which can contain any 8 bit data), with
length "size".
As a special case, if "size" is 0 then the length is calculated
using "strlen" (so in this case the content cannot contain embedded
ASCII NULs).
NB. Owing to a bug, writing content containing ASCII NUL characters
does not work, even if the length is specified.
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
This function is deprecated. In new code, use the "write" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->xfs_admin ($device [, extunwritten => $extunwritten] [, imgfile =>
$imgfile] [, v2log => $v2log] [, projid32bit => $projid32bit] [,
lazycounter => $lazycounter] [, label => $label] [, uuid => $uuid]);
Change the parameters of the XFS filesystem on "device".
Devices that are mounted cannot be modified. Administrators must
unmount filesystems before this call can modify parameters.
Some of the parameters of a mounted filesystem can be examined and
modified using the "$g->xfs_info" and "$g->xfs_growfs" calls.
$g->xfs_growfs ($path [, datasec => $datasec] [, logsec => $logsec] [,
rtsec => $rtsec] [, datasize => $datasize] [, logsize => $logsize] [,
rtsize => $rtsize] [, rtextsize => $rtextsize] [, maxpct => $maxpct]);
Grow the XFS filesystem mounted at "path".
The returned struct contains geometry information. Missing fields
are returned as "-1" (for numeric fields) or empty string.
%info = $g->xfs_info ($pathordevice);
"pathordevice" is a mounted XFS filesystem or a device containing
an XFS filesystem. This command returns the geometry of the
filesystem.
The returned struct contains geometry information. Missing fields
are returned as "-1" (for numeric fields) or empty string.
$status = $g->xfs_repair ($device [, forcelogzero => $forcelogzero] [,
nomodify => $nomodify] [, noprefetch => $noprefetch] [, forcegeometry
=> $forcegeometry] [, maxmem => $maxmem] [, ihashsize => $ihashsize] [,
bhashsize => $bhashsize] [, agstride => $agstride] [, logdev =>
$logdev] [, rtdev => $rtdev]);
Repair corrupt or damaged XFS filesystem on "device".
The filesystem is specified using the "device" argument which
should be the device name of the disk partition or volume
containing the filesystem. If given the name of a block device,
"xfs_repair" will attempt to find the raw device associated with
the specified block device and will use the raw device instead.
Regardless, the filesystem to be repaired must be unmounted,
otherwise, the resulting filesystem may be inconsistent or corrupt.
The returned status indicates whether filesystem corruption was
detected (returns 1) or was not detected (returns 0).
@lines = $g->zegrep ($regex, $path);
This calls the external "zegrep" program and returns the matching
lines.
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
This function is deprecated. In new code, use the "grep" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
@lines = $g->zegrepi ($regex, $path);
This calls the external "zegrep -i" program and returns the
matching lines.
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
This function is deprecated. In new code, use the "grep" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$g->zero ($device);
This command writes zeroes over the first few blocks of "device".
How many blocks are zeroed isn't specified (but it's not enough to
securely wipe the device). It should be sufficient to remove any
partition tables, filesystem superblocks and so on.
If blocks are already zero, then this command avoids writing
zeroes. This prevents the underlying device from becoming non-
sparse or growing unnecessarily.
See also: "$g->zero_device", "$g->scrub_device",
"$g->is_zero_device"
$g->zero_device ($device);
This command writes zeroes over the entire "device". Compare with
"$g->zero" which just zeroes the first few blocks of a device.
If blocks are already zero, then this command avoids writing
zeroes. This prevents the underlying device from becoming non-
sparse or growing unnecessarily.
$g->zero_free_space ($directory);
Zero the free space in the filesystem mounted on "directory". The
filesystem must be mounted read-write.
The filesystem contents are not affected, but any free space in the
filesystem is freed.
Free space is not "trimmed". You may want to call "$g->fstrim"
either as an alternative to this, or after calling this, depending
on your requirements.
$g->zerofree ($device);
This runs the zerofree program on "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 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.
@lines = $g->zfgrep ($pattern, $path);
This calls the external "zfgrep" program and returns the matching
lines.
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
This function is deprecated. In new code, use the "grep" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
@lines = $g->zfgrepi ($pattern, $path);
This calls the external "zfgrep -i" program and returns the
matching lines.
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
This function is deprecated. In new code, use the "grep" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
$description = $g->zfile ($meth, $path);
This command runs "file" after first decompressing "path" using
"method".
"method" must be one of "gzip", "compress" or "bzip2".
Since 1.0.63, use "$g->file" instead which can now process
compressed files.
This function is deprecated. In new code, use the "file" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
@lines = $g->zgrep ($regex, $path);
This calls the external "zgrep" program and returns the matching
lines.
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
This function is deprecated. In new code, use the "grep" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
@lines = $g->zgrepi ($regex, $path);
This calls the external "zgrep -i" program and returns the matching
lines.
Because of the message protocol, there is a transfer limit of
somewhere between 2MB and 4MB. See "PROTOCOL LIMITS" in
guestfs(3).
This function is deprecated. In new code, use the "grep" call
instead.
Deprecated functions will not be removed from the API, but the fact
that they are deprecated indicates that there are problems with
correct use of these functions.
AVAILABILITY
From time to time we add new libguestfs APIs. Also some libguestfs
APIs won't be available in all builds of libguestfs (the Fedora build
is full-featured, but other builds may disable features). How do you
test whether the APIs that your Perl program needs are available in the
version of "Sys::Guestfs" that you are using?
To test if a particular function is available in the "Sys::Guestfs"
class, use the ordinary Perl UNIVERSAL method "can(METHOD)" (see
perlobj(1)). For example:
use Sys::Guestfs;
if (defined (Sys::Guestfs->can ("set_verbose"))) {
print "\$g->set_verbose is available\n";
}
Perl does not offer a way to list the arguments of a method, and from
time to time we may add extra arguments to calls that take optional
arguments. For this reason, we provide a global hash variable
%guestfs_introspection which contains the arguments and their types for
each libguestfs method. The keys of this hash are the method names,
and the values are an hashref containing useful introspection
information about the method (further fields may be added to this in
future).
use Sys::Guestfs;
$Sys::Guestfs::guestfs_introspection{mkfs}
=> {
ret => 'void', # return type
args => [ # required arguments
[ 'fstype', 'string', 0 ],
[ 'device', 'string(device)', 1 ],
],
optargs => { # optional arguments
blocksize => [ 'blocksize', 'int', 0 ],
features => [ 'features', 'string', 1 ],
inode => [ 'inode', 'int', 2 ],
sectorsize => [ 'sectorsize', 'int', 3 ],
},
name => "mkfs",
description => "make a filesystem",
}
To test if particular features are supported by the current build, use
the "feature_available" method like the example below. Note that the
appliance must be launched first.
$g->feature_available ( ["augeas"] );
For further discussion on this topic, refer to "AVAILABILITY" in
guestfs(3).
STORING DATA IN THE HANDLE
The handle returned from "new" is a hash reference. The hash normally
contains some elements:
{
_g => [private data used by libguestfs],
_flags => [flags provided when creating the handle]
}
Callers can add other elements to this hash to store data for their own
purposes. The data lasts for the lifetime of the handle.
Any fields whose names begin with an underscore are reserved for
private use by libguestfs. We may add more in future.
It is recommended that callers prefix the name of their field(s) with
some unique string, to avoid conflicts with other users.
COPYRIGHT
Copyright (C) 2009-2013 Red Hat Inc.
LICENSE
Please see the file COPYING.LIB for the full license.
SEE ALSOguestfs(3), guestfish(1), <http://libguestfs.org>.
perl v5.16.3 2013-10-31 Sys::Guestfs(3)
