Provided by: libguestfs-perl_1.24.5-1ubuntu0.1_amd64 
NAME
Sys::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_WARNING
See "GUESTFS_EVENT_WARNING" 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 = "ftp"|"ftps"|"http"|"https"|"tftp""
Connect to a remote FTP, HTTP or TFTP server. The "server" parameter must also be supplied -
see below.
See also: "FTP, HTTP AND TFTP" in guestfs(3)
"protocol = "gluster""
Connect to the GlusterFS server. The "server" parameter must also be supplied - see below.
See also: "GLUSTER" in guestfs(3)
"protocol = "iscsi""
Connect to the iSCSI server. The "server" parameter must also be supplied - see below.
See also: "ISCSI" in guestfs(3).
"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).
"protocol = "rbd""
Connect to the Ceph (librbd/RBD) server. The "server" parameter must also be supplied - see
below. The "username" parameter may be supplied. See below. The "secret" parameter may be
supplied. See below.
See also: "CEPH" in guestfs(3).
"protocol = "sheepdog""
Connect to the Sheepdog server. The "server" parameter may also be supplied - see below.
See also: "SHEEPDOG" in guestfs(3).
"protocol = "ssh""
Connect to the Secure Shell (ssh) server.
The "server" parameter must be supplied. The "username" parameter may be supplied. See
below.
See also: "SSH" 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
ftp|ftps|http|https|tftp Exactly one
gluster Exactly one
iscsi Exactly one
nbd Exactly one
rbd One or more
sheepdog Zero or more
ssh 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").
"username"
For the "ftp", "ftps", "http", "https", "iscsi", "rbd", "ssh" and "tftp" protocols, this
specifies the remote username.
If not given, then the local username is used for "ssh", and no authentication is attempted for
ceph. But note this sometimes may give unexpected results, for example if using the libvirt
backend and if the libvirt backend is configured to start the qemu appliance as a special user
such as "qemu.qemu". If in doubt, specify the remote username you want.
"secret"
For the "rbd" protocol only, this specifies the 'secret' to use when connecting to the remote
device.
If not given, then a secret matching the given username will be looked up in the default keychain
locations, or if no username is given, then no authentication will be used.
"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]".
$label = $g->aug_label ($augpath);
The label (name of the last element) of the Augeas path expression "augpath" is returned. "augpath"
must match exactly one node, else this function returns an error.
$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.
$nodes = $g->aug_setm ($base, $sub, $val);
Change multiple Augeas nodes in a single operation. "base" is an expression matching multiple nodes.
"sub" is a path expression relative to "base". All nodes matching "base" are found, and then for
each node, "sub" is changed to "val". "sub" may also be "NULL" in which case the "base" nodes are
modified.
This returns the number of nodes modified.
$g->available (\@groups);
This command is used to check the availability of some groups of functionality in the appliance,
which not all builds of the libguestfs appliance will be able to provide.
The libguestfs groups, and the functions that those groups correspond to, are listed in
"AVAILABILITY" in guestfs(3). You can also fetch this list at runtime by calling
"$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>
"$g->case_sensitive_path" attempts to resolve the true case of each element in the path. It will
return a resolved path if either the full path or its parent directory exists. If the parent
directory exists but the full path does not, the case of the parent directory will be correctly
resolved, and the remainder appended unmodified. For example, if the file
"/Windows/System32/netkvm.sys" exists:
"$g->case_sensitive_path" ("/windows/system32/netkvm.sys")
"Windows/System32/netkvm.sys"
"$g->case_sensitive_path" ("/windows/system32/NoSuchFile")
"Windows/System32/NoSuchFile"
"$g->case_sensitive_path" ("/windows/system33/netkvm.sys")
ERROR
Note: Because of the above behaviour, "$g->case_sensitive_path" cannot be used to check for the
existence of a file.
Note: This function does not handle drive names, backslashes etc.
See also "$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.
$g->config ($hvparam, $hvvalue);
This can be used to add arbitrary hypervisor 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 "hvparam" string must be a "-" (dash).
"hvvalue" 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.
$hv = $g->get_hv ();
Return the current hypervisor binary.
This is always non-NULL. If it wasn't set already, then this will return the default qemu binary
name.
$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 = $g->get_memsize ();
This gets the memory size in megabytes allocated to the hypervisor.
If "$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 hypervisor. If there is no hypervisor running, 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".
$hv = $g->get_qemu ();
Return the current hypervisor binary (usually qemu).
This is always non-NULL. If it wasn't set already, then this will return the default qemu binary
name.
This function is deprecated. In new code, use the "get_hv" 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.
$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->journal_close ();
Close the journal handle.
@fields = $g->journal_get ();
Read the current journal entry. This returns all the fields in the journal as a set of "(attrname,
attrval)" pairs. The "attrname" is the field name (a string).
The "attrval" is the field value (a binary blob, often but not always a string). Please note that
"attrval" is a byte array, not a \0-terminated C string.
The length of data may be truncated to the data threshold (see: "$g->journal_set_data_threshold",
"$g->journal_get_data_threshold").
If you set the data threshold to unlimited (0) then this call can read a journal entry of any size,
ie. it is not limited by the libguestfs protocol.
$threshold = $g->journal_get_data_threshold ();
Get the current data threshold for reading journal entries. This is a hint to the journal that it
may truncate data fields to this size when reading them (note also that it may not truncate them).
If this returns 0, then the threshold is unlimited.
See also "$g->journal_set_data_threshold".
$more = $g->journal_next ();
Move to the next journal entry. You have to call this at least once after opening the handle before
you are able to read data.
The returned boolean tells you if there are any more journal records to read. "true" means you can
read the next record (eg. using "$g->journal_get_data"), and "false" means you have reached the end
of the journal.
$g->journal_open ($directory);
Open the systemd journal located in "directory". Any previously opened journal handle is closed.
The contents of the journal can be read using "$g->journal_next" and "$g->journal_get".
After you have finished using the journal, you should close the handle by calling
"$g->journal_close".
$g->journal_set_data_threshold ($threshold);
Set the data threshold for reading journal entries. This is a hint to the journal that it may
truncate data fields to this size when reading them (note also that it may not truncate them). If
you set this to 0, then the threshold is unlimited.
See also "$g->journal_get_data_threshold".
$rskip = $g->journal_skip ($skip);
Skip forwards ("skip X 0") or backwards ("skip < 0") in the journal.
The number of entries actually skipped is returned (note "rskip X 0"). If this is not the same as
the absolute value of the skip parameter ("|skip|") you passed in then it means you have reached the
end or the start of the journal.
$g->kill_subprocess ();
This kills the hypervisor.
Do not call this. See: "$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.
$g->launch ();
You should call this after configuring the handle (eg. adding drives) but before performing any
actions.
Do not call "$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.
@mounttags = $g->list_9p ();
List all 9p filesystems attached to the guest. A list of mount tags is returned.
@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).
$g->mount_9p ($mounttag, $mountpoint [, options => $options]);
Mount the virtio-9p filesystem with the tag "mounttag" on the directory "mountpoint".
If required, "trans=virtio" will be automatically added to the options. Any other options required
can be passed in the optional "options" parameter.
$g->mount_local ($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 hypervisor. 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.
$g->set_hv ($hv);
Set the hypervisor binary that we will use. The hypervisor depends on the backend, but is usually
the location of the qemu/KVM hypervisor. For the uml backend, it is the location of the "linux" or
"vmlinux" binary.
The default is chosen when the library was compiled by the configure script.
You can also override this by setting the "LIBGUESTFS_HV" environment variable.
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_HV" is safest of all since that picks the qemu binary at the same
time as the handle is created.
$g->set_label ($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 hypervisor. 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").
$g->set_qemu ($hv);
Set the hypervisor binary (usually qemu) 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_HV" environment variable.
Setting "hv" 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_HV" is safest of all since that picks the qemu binary at the same
time as the handle is created.
This function is deprecated. In new code, use the "set_hv" 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.
$g->set_recovery_proc ($recoveryproc);
If this is called with the parameter "false" then "$g->launch" does not create a recovery process.
The purpose of the recovery process is to stop runaway hypervisor processes in the case where the
main program aborts abruptly.
This only has any effect if called before "$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 the hypervisor, 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) 2009-2015 Red Hat Inc.
LICENSE
Please see the file COPYING.LIB for the full license.
SEE ALSO
guestfs(3), guestfish(1), <http://libguestfs.org>.
perl v5.18.2 2015-10-14 Sys::Guestfs(3pm)