HANDLES¶

Before you can use libguestfs calls, you have to create a handle. Then you must add at least one disk image to the handle, followed by launching the handle, then performing whatever operations you want, and finally closing the handle. By convention we use the single letter "g" for the name of the handle variable, although of course you can use any name you want.

The general structure of all libguestfs-using programs looks like this:

 guestfs_h *g = guestfs_create ();
 
 /* Call guestfs_add_drive additional times if there are
  * multiple disk images.
  */
 guestfs_add_drive (g, "guest.img");
 
 /* Most manipulation calls won't work until you've launched
  * the handle 'g'.  You have to do this _after_ adding drives
  * and _before_ other commands.
  */
 guestfs_launch (g);
 
 /* Either: examine what partitions, LVs etc are available: */
 char **partitions = guestfs_list_partitions (g);
 char **logvols = guestfs_lvs (g);
 
 /* Or: ask libguestfs to find filesystems for you: */
 char **filesystems = guestfs_list_filesystems (g);
 
 /* Or: use inspection (see INSPECTION section below). */
 
 /* To access a filesystem in the image, you must mount it. */
 guestfs_mount (g, "/dev/sda1", "/");
 
 /* Now you can perform filesystem actions on the guest
  * disk image.
  */
 guestfs_touch (g, "/hello");
 
 /* Synchronize the disk.  This is the opposite of guestfs_launch. */
 guestfs_shutdown (g);
 
 /* Close and free the handle 'g'. */
 guestfs_close (g);

The code above doesn't include any error checking. In real code you should check return values carefully for errors. In general all functions that return integers return -1 on error, and all functions that return pointers return "NULL" on error. See section "ERROR HANDLING" below for how to handle errors, and consult the documentation for each function call below to see precisely how they return error indications.

The code above does not free(3) the strings and arrays returned from functions. Consult the documentation for each function to find out how to free the return value.

See guestfs-examples(3) for fully worked examples.

DISK IMAGES¶

The image filename ("guest.img" in the example above) could be a disk image from a virtual machine, a dd(1) copy of a physical hard disk, an actual block device, or simply an empty file of zeroes that you have created through posix_fallocate(3). Libguestfs lets you do useful things to all of these.

The call you should use in modern code for adding drives is "guestfs_add_drive_opts". To add a disk image, allowing writes, and specifying that the format is raw, do:

 guestfs_add_drive_opts (g, filename,
                         GUESTFS_ADD_DRIVE_OPTS_FORMAT, "raw",
                         -1);

You can add a disk read-only using:

 guestfs_add_drive_opts (g, filename,
                         GUESTFS_ADD_DRIVE_OPTS_FORMAT, "raw",
                         GUESTFS_ADD_DRIVE_OPTS_READONLY, 1,
                         -1);

or by calling the older function "guestfs_add_drive_ro". If you use the readonly flag, libguestfs won't modify the file. (See also "DISK IMAGE FORMATS" below).

Be extremely cautious if the disk image is in use, eg. if it is being used by a virtual machine. Adding it read-write will almost certainly cause disk corruption, but adding it read-only is safe.

You should usually add at least one disk image, and you may add multiple disk images. If adding multiple disk images, they usually have to be "related", ie. from the same guest. In the API, the disk images are usually referred to as /dev/sda (for the first one you added), /dev/sdb (for the second one you added), etc.

Once "guestfs_launch" has been called you cannot add any more images. You can call "guestfs_list_devices" to get a list of the device names, in the order that you added them. See also "BLOCK DEVICE NAMING" below.

MOUNTING¶

Before you can read or write files, create directories and so on in a disk image that contains filesystems, you have to mount those filesystems using "guestfs_mount" or "guestfs_mount_ro". If you already know that a disk image contains (for example) one partition with a filesystem on that partition, then you can mount it directly:

 guestfs_mount (g, "/dev/sda1", "/");

where /dev/sda1 means literally the first partition (1) of the first disk image that we added (/dev/sda). If the disk contains Linux LVM2 logical volumes you could refer to those instead (eg. /dev/VG/LV). Note that these are libguestfs virtual devices, and are nothing to do with host devices.

If you are given a disk image and you don’t know what it contains then you have to find out. Libguestfs can do that too: use "guestfs_list_partitions" and "guestfs_lvs" to list possible partitions and LVs, and either try mounting each to see what is mountable, or else examine them with "guestfs_vfs_type" or "guestfs_file". To list just filesystems, use "guestfs_list_filesystems".

Libguestfs also has a set of APIs for inspection of unknown disk images (see "INSPECTION" below). You might also want to look at higher level programs built on top of libguestfs, in particular virt-inspector(1).

To mount a filesystem read-only, use "guestfs_mount_ro". There are several other variations of the "guestfs_mount_*" call.

FILESYSTEM ACCESS AND MODIFICATION¶

The majority of the libguestfs API consists of fairly low-level calls for accessing and modifying the files, directories, symlinks etc on mounted filesystems. There are over a hundred such calls which you can find listed in detail below in this man page, and we don't even pretend to cover them all in this overview.

Specify filenames as full paths, starting with "/" and including the mount point.

For example, if you mounted a filesystem at "/" and you want to read the file called "etc/passwd" then you could do:

 char *data = guestfs_cat (g, "/etc/passwd");

This would return "data" as a newly allocated buffer containing the full content of that file (with some conditions: see also "DOWNLOADING" below), or "NULL" if there was an error.

As another example, to create a top-level directory on that filesystem called "var" you would do:

 guestfs_mkdir (g, "/var");

To create a symlink you could do:

 guestfs_ln_s (g, "/etc/init.d/portmap",
               "/etc/rc3.d/S30portmap");

Libguestfs will reject attempts to use relative paths and there is no concept of a current working directory.

Libguestfs can return errors in many situations: for example if the filesystem isn't writable, or if a file or directory that you requested doesn't exist. If you are using the C API (documented here) you have to check for those error conditions after each call. (Other language bindings turn these errors into exceptions).

File writes are affected by the per-handle umask, set by calling "guestfs_umask" and defaulting to 022. See "UMASK".

Since libguestfs 1.18, it is possible to mount the libguestfs filesystem on a local directory, subject to some restrictions. See "MOUNT LOCAL" below.

PARTITIONING¶

Libguestfs contains API calls to read, create and modify partition tables on disk images.

In the common case where you want to create a single partition covering the whole disk, you should use the "guestfs_part_disk" call:

 const char *parttype = "mbr";
 if (disk_is_larger_than_2TB)
   parttype = "gpt";
 guestfs_part_disk (g, "/dev/sda", parttype);

Obviously this effectively wipes anything that was on that disk image before.

LVM2¶

Libguestfs provides access to a large part of the LVM2 API, such as "guestfs_lvcreate" and "guestfs_vgremove". It won't make much sense unless you familiarize yourself with the concepts of physical volumes, volume groups and logical volumes.

This author strongly recommends reading the LVM HOWTO, online at http://tldp.org/HOWTO/LVM-HOWTO/.

DOWNLOADING¶

Use "guestfs_cat" to download small, text only files. This call cannot handle files containing any ASCII NUL ("\0") characters. However the API is very simple to use.

"guestfs_read_file" can be used to read files which contain arbitrary 8 bit data, since it returns a (pointer, size) pair.

"guestfs_download" can be used to download any file, with no limits on content or size.

To download multiple files, see "guestfs_tar_out" and "guestfs_tgz_out".

UPLOADING¶

To write a small file with fixed content, use "guestfs_write". To create a file of all zeroes, use "guestfs_truncate_size" (sparse) or "guestfs_fallocate64" (with all disk blocks allocated). There are a variety of other functions for creating test files, for example "guestfs_fill" and "guestfs_fill_pattern".

To upload a single file, use "guestfs_upload". This call has no limits on file content or size.

To upload multiple files, see "guestfs_tar_in" and "guestfs_tgz_in".

However the fastest way to upload large numbers of arbitrary files is to turn them into a squashfs or CD ISO (see mksquashfs(8) and mkisofs(8)), then attach this using "guestfs_add_drive_ro". If you add the drive in a predictable way (eg. adding it last after all other drives) then you can get the device name from "guestfs_list_devices" and mount it directly using "guestfs_mount_ro". Note that squashfs images are sometimes non-portable between kernel versions, and they don't support labels or UUIDs. If you want to pre-build an image or you need to mount it using a label or UUID, use an ISO image instead.

COPYING¶

There are various different commands for copying between files and devices and in and out of the guest filesystem. These are summarised in the table below.

file to file

Use "guestfs_cp" to copy a single file, or "guestfs_cp_a" to copy directories recursively.

To copy part of a file (offset and size) use "guestfs_copy_file_to_file".

file to device

device to file

device to device

Use "guestfs_copy_file_to_device", "guestfs_copy_device_to_file", or "guestfs_copy_device_to_device".

Example: duplicate the contents of an LV:

 guestfs_copy_device_to_device (g,
         "/dev/VG/Original", "/dev/VG/Copy",
         /* -1 marks the end of the list of optional parameters */
         -1);
    

The destination (/dev/VG/Copy) must be at least as large as the source (/dev/VG/Original). To copy less than the whole source device, use the optional "size" parameter:

 guestfs_copy_device_to_device (g,
         "/dev/VG/Original", "/dev/VG/Copy",
         GUESTFS_COPY_DEVICE_TO_DEVICE_SIZE, 10000,
         -1);
    

file on the host to file or device

Use "guestfs_upload". See "UPLOADING" above.

file or device to file on the host

Use "guestfs_download". See "DOWNLOADING" above.

UPLOADING AND DOWNLOADING TO PIPES AND FILE DESCRIPTORS¶

Calls like "guestfs_upload", "guestfs_download", "guestfs_tar_in", "guestfs_tar_out" etc appear to only take filenames as arguments, so it appears you can only upload and download to files. However many Un*x-like hosts let you use the special device files /dev/stdin, /dev/stdout, /dev/stderr and /dev/fd/N to read and write from stdin, stdout, stderr, and arbitrary file descriptor N.

For example, virt-cat(1) writes its output to stdout by doing:

 guestfs_download (g, filename, "/dev/stdout");

and you can write tar output to a file descriptor "fd" by doing:

 char devfd[64];
 snprintf (devfd, sizeof devfd, "/dev/fd/%d", fd);
 guestfs_tar_out (g, "/", devfd);

LISTING FILES¶

"guestfs_ll" is just designed for humans to read (mainly when using the guestfish(1)-equivalent command "ll").

"guestfs_ls" is a quick way to get a list of files in a directory from programs, as a flat list of strings.

"guestfs_readdir" is a programmatic way to get a list of files in a directory, plus additional information about each one. It is more equivalent to using the readdir(3) call on a local filesystem.

"guestfs_find" and "guestfs_find0" can be used to recursively list files.

RUNNING COMMANDS¶

Although libguestfs is primarily an API for manipulating files inside guest images, we also provide some limited facilities for running commands inside guests.

There are many limitations to this:

• The kernel version that the command runs under will be different from what it expects.
• If the command needs to communicate with daemons, then most likely they won't be running.
• The command will be running in limited memory.
• The network may not be available unless you enable it (see "guestfs_set_network").
• Only supports Linux guests (not Windows, BSD, etc).
• Architecture limitations (eg. won’t work for a PPC guest on an X86 host).
• For SELinux guests, you may need to relabel the guest after creating new files. See "SELINUX" below.
• Security: It is not safe to run commands from untrusted, possibly malicious guests. These commands may attempt to exploit your program by sending unexpected output. They could also try to exploit the Linux kernel or qemu provided by the libguestfs appliance. They could use the network provided by the libguestfs appliance to bypass ordinary network partitions and firewalls. They could use the elevated privileges or different SELinux context of your program to their advantage.

  A secure alternative is to use libguestfs to install a "firstboot" script (a script which runs when the guest next boots normally), and to have this script run the commands you want in the normal context of the running guest, network security and so on. For information about other security issues, see guestfs-security(1).

The two main API calls to run commands are "guestfs_command" and "guestfs_sh" (there are also variations).

The difference is that "guestfs_sh" runs commands using the shell, so any shell globs, redirections, etc will work.

CONFIGURATION FILES¶

To read and write configuration files in Linux guest filesystems, we strongly recommend using Augeas. For example, Augeas understands how to read and write, say, a Linux shadow password file or X.org configuration file, and so avoids you having to write that code.

The main Augeas calls are bound through the "guestfs_aug_*" APIs. We don't document Augeas itself here because there is excellent documentation on the http://augeas.net/ website.

If you don’t want to use Augeas (you fool!) then try calling "guestfs_read_lines" to get the file as a list of lines which you can iterate over.

SYSTEMD JOURNAL FILES¶

To read the systemd journal from a Linux guest, use the "guestfs_journal_*" APIs starting with "guestfs_journal_open".

Consult the journal documentation here: sd-journal(3), sd_journal_open(3).

SELINUX¶

We support SELinux guests. However it is not possible to load the SELinux policy of the guest into the appliance kernel. Therefore the strategy for dealing with SELinux guests is to relabel them after making changes.

In libguestfs ≥ 1.34 there is a new API, "guestfs_setfiles", which can be used for this. To properly use this API you have to parse the guest SELinux configuration. See the virt-customize(1) module customize/SELinux_relabel.ml for how to do this.

A simpler but slower alternative is to touch /.autorelabel in the guest, which means that the guest will relabel itself at next boot.

Libguestfs ≤ 1.32 had APIs "guestfs_set_selinux", "guestfs_get_selinux", "guestfs_setcon" and "guestfs_getcon". These did not work properly, are deprecated, and should not be used in new code.

UMASK¶

Certain calls are affected by the current file mode creation mask (the "umask"). In particular ones which create files or directories, such as "guestfs_touch", "guestfs_mknod" or "guestfs_mkdir". This affects either the default mode that the file is created with or modifies the mode that you supply.

The default umask is 022, so files are created with modes such as 0644 and directories with 0755.

There are two ways to avoid being affected by umask. Either set umask to 0 (call "guestfs_umask (g, 0)" early after launching). Or call "guestfs_chmod" after creating each file or directory.

For more information about umask, see umask(2).

LABELS AND UUIDS¶

Many filesystems, devices and logical volumes support either labels (short strings like "BOOT" which might not be unique) and/or UUIDs (globally unique IDs).

For filesystems, use "guestfs_vfs_label" or "guestfs_vfs_uuid" to read the label or UUID. Some filesystems let you call "guestfs_set_label" or "guestfs_set_uuid" to change the label or UUID.

You can locate a filesystem by its label or UUID using "guestfs_findfs_label" or "guestfs_findfs_uuid".

For LVM2 (which supports only UUIDs), there is a rich set of APIs for fetching UUIDs, fetching UUIDs of the contained objects, and changing UUIDs. See: "guestfs_lvuuid", "guestfs_vguuid", "guestfs_pvuuid", "guestfs_vglvuuids", "guestfs_vgpvuuids", "guestfs_vgchange_uuid", "guestfs_vgchange_uuid_all", "guestfs_pvchange_uuid", "guestfs_pvchange_uuid_all".

Note when cloning a filesystem, device or whole guest, it is a good idea to set new randomly generated UUIDs on the copy.

ENCRYPTED DISKS¶

Libguestfs allows you to access Linux guests which have been encrypted using whole disk encryption that conforms to the Linux Unified Key Setup (LUKS) standard. This includes nearly all whole disk encryption systems used by modern Linux guests. Windows BitLocker is also supported.

Use "guestfs_vfs_type" to identify encrypted block devices. For LUKS it returns the string "crypto_LUKS". For Windows BitLocker it returns "BitLocker".

Then open these devices by calling "guestfs_cryptsetup_open". Obviously you will require the passphrase!

Passphrase-less unlocking is supported for LUKS (not BitLocker) block devices that have been encrypted with network-bound disk encryption (NBDE), using Clevis on the Linux guest side, and Tang on a separate Linux server. Open such devices with "guestfs_clevis_luks_unlock". The appliance will need networking enabled (refer to "guestfs_set_network") and actual connectivity to the Tang servers noted in the "tang" Clevis pins that are bound to the LUKS header. (This includes the ability to resolve the names of the Tang servers.)

Opening an encrypted device creates a new device mapper device called /dev/mapper/mapname (where "mapname" is the string you supply to "guestfs_cryptsetup_open" or "guestfs_clevis_luks_unlock"). Reads and writes to this mapper device are decrypted from and encrypted to the underlying block device respectively.

LVM volume groups on the device can be made visible by calling "guestfs_vgscan" followed by "guestfs_vg_activate_all". The logical volume(s) can now be mounted in the usual way.

Use the reverse process to close an encrypted device. Unmount any logical volumes on it, deactivate the volume groups by calling "guestfs_vg_activate (g, 0, ["/dev/VG"])". Then close the mapper device by calling "guestfs_cryptsetup_close" on the /dev/mapper/mapname device (not the underlying encrypted block device).

MOUNT LOCAL¶

In libguestfs ≥ 1.18, it is possible to mount the libguestfs filesystem on a local directory and access it using ordinary POSIX calls and programs.

Availability of this is subject to a number of restrictions: it requires FUSE (the Filesystem in USErspace), and libfuse must also have been available when libguestfs was compiled. FUSE may require that a kernel module is loaded, and it may be necessary to add the current user to a special "fuse" group. See the documentation for your distribution and http://fuse.sf.net for further information.

The call to mount the libguestfs filesystem on a local directory is "guestfs_mount_local" (q.v.) followed by "guestfs_mount_local_run". The latter does not return until you unmount the filesystem. The reason is that the call enters the FUSE main loop and processes kernel requests, turning them into libguestfs calls. An alternative design would have been to create a background thread to do this, but libguestfs doesn't require pthreads. This way is also more flexible: for example the user can create another thread for "guestfs_mount_local_run".

"guestfs_mount_local" needs a certain amount of time to set up the mountpoint. The mountpoint is not ready to use until the call returns. At this point, accesses to the filesystem will block until the main loop is entered (ie. "guestfs_mount_local_run"). So if you need to start another process to access the filesystem, put the fork between "guestfs_mount_local" and "guestfs_mount_local_run".

MOUNT LOCAL COMPATIBILITY

Since local mounting was only added in libguestfs 1.18, and may not be available even in these builds, you should consider writing code so that it doesn't depend on this feature, and can fall back to using libguestfs file system calls.

If libguestfs was compiled without support for "guestfs_mount_local" then calling it will return an error with errno set to "ENOTSUP" (see "guestfs_last_errno").

MOUNT LOCAL PERFORMANCE

Libguestfs on top of FUSE performs quite poorly. For best performance do not use it. Use ordinary libguestfs filesystem calls, upload, download etc. instead.

REMOTE STORAGE¶

CEPH

Libguestfs can access Ceph (librbd/RBD) disks.

To do this, set the optional "protocol" and "server" parameters of "guestfs_add_drive_opts" like this:

 char **servers = { "ceph1.example.org:3000", /* ... */, NULL };
 guestfs_add_drive_opts (g, "pool/image",
                         GUESTFS_ADD_DRIVE_OPTS_FORMAT, "raw",
                         GUESTFS_ADD_DRIVE_OPTS_PROTOCOL, "rbd",
                         GUESTFS_ADD_DRIVE_OPTS_SERVER, servers,
                         GUESTFS_ADD_DRIVE_OPTS_USERNAME, "rbduser",
                         GUESTFS_ADD_DRIVE_OPTS_SECRET, "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA==",
                         -1);

"servers" (the "server" parameter) is a list of one or more Ceph servers. The server string is documented in "guestfs_add_drive_opts". The "username" and "secret" parameters are also optional, and if not given, then no authentication will be used.

An encrypted RBD disk -- directly opening which would require the "username" and "secret" parameters -- cannot be accessed if the following conditions all hold:

• the backend is libvirt,
• the image specified by the "filename" parameter is different from the encrypted RBD disk,
• the image specified by the "filename" parameter has qcow2 format,
• the encrypted RBD disk is specified as a backing file at some level in the qcow2 backing chain.

This limitation is due to libvirt's (justified) separate handling of disks vs. secrets. When the RBD username and secret are provided inside a qcow2 backing file specification, libvirt does not construct an ephemeral secret object from those, for Ceph authentication. Refer to https://bugzilla.redhat.com/2033247.

FTP AND HTTP

Libguestfs can access remote disks over FTP, FTPS, HTTP or HTTPS protocols.

To do this, set the optional "protocol" and "server" parameters of "guestfs_add_drive_opts" like this:

 char **servers = { "www.example.org", NULL };
 guestfs_add_drive_opts (g, "/disk.img",
                         GUESTFS_ADD_DRIVE_OPTS_FORMAT, "raw",
                         GUESTFS_ADD_DRIVE_OPTS_PROTOCOL, "http",
                         GUESTFS_ADD_DRIVE_OPTS_SERVER, servers,
                         -1);

The "protocol" can be one of "ftp", "ftps", "http", or "https".

"servers" (the "server" parameter) is a list which must have a single element. The single element is a string defining the web or FTP server. The format of this string is documented in "guestfs_add_drive_opts".

GLUSTER

Glusterfs support was removed in libguestfs 1.54 (2024).

ISCSI

Libguestfs can access iSCSI disks remotely.

To do this, set the optional "protocol" and "server" parameters like this:

 char **server = { "iscsi.example.org:3000", NULL };
 guestfs_add_drive_opts (g, "target-iqn-name/lun",
                         GUESTFS_ADD_DRIVE_OPTS_FORMAT, "raw",
                         GUESTFS_ADD_DRIVE_OPTS_PROTOCOL, "iscsi",
                         GUESTFS_ADD_DRIVE_OPTS_SERVER, server,
                         -1);

The "server" parameter is a list which must have a single element. The single element is a string defining the iSCSI server. The format of this string is documented in "guestfs_add_drive_opts".

NETWORK BLOCK DEVICE

Libguestfs can access Network Block Device (NBD) disks remotely.

To do this, set the optional "protocol" and "server" parameters of "guestfs_add_drive_opts" like this:

 char **server = { "nbd.example.org:3000", NULL };
 guestfs_add_drive_opts (g, "" /* export name - see below */,
                         GUESTFS_ADD_DRIVE_OPTS_FORMAT, "raw",
                         GUESTFS_ADD_DRIVE_OPTS_PROTOCOL, "nbd",
                         GUESTFS_ADD_DRIVE_OPTS_SERVER, server,
                         -1);

Notes:

• "server" is in fact a list of servers. For NBD you must always supply a list with a single element. (Other remote protocols require zero or more than one server, hence the requirement for this parameter to be a list).
• The "server" string is documented in "guestfs_add_drive_opts". To connect to a local qemu-nbd instance over a Unix domain socket, use "unix:/path/to/socket".
• The "filename" parameter is the NBD export name. Use an empty string to mean the default export. Many NBD servers, including qemu-nbd, do not support export names.
• If using qemu-nbd as your server, you should always specify the "-t" option. The reason is that libguestfs may open several connections to the server.
• The libvirt backend requires that you set the "format" parameter of "guestfs_add_drive_opts" accurately when you use writable NBD disks.
• The libvirt backend has a bug that stops Unix domain socket connections from working: https://bugzilla.redhat.com/show_bug.cgi?id=922888
• The direct backend does not support readonly connections because of a bug in qemu: https://bugs.launchpad.net/qemu/+bug/1155677

SHEEPDOG

Sheepdog support was removed in libguestfs 1.54 (2024).

SSH

Libguestfs can access disks over a Secure Shell (SSH) connection.

To do this, set the "protocol" and "server" and (optionally) "username" parameters of "guestfs_add_drive_opts" like this:

 char **server = { "remote.example.com", NULL };
 guestfs_add_drive_opts (g, "/path/to/disk.img",
                         GUESTFS_ADD_DRIVE_OPTS_FORMAT, "raw",
                         GUESTFS_ADD_DRIVE_OPTS_PROTOCOL, "ssh",
                         GUESTFS_ADD_DRIVE_OPTS_SERVER, server,
                         GUESTFS_ADD_DRIVE_OPTS_USERNAME, "remoteuser",
                         -1);

The format of the server string is documented in "guestfs_add_drive_opts".

INSPECTION¶

Libguestfs has APIs for inspecting an unknown disk image to find out if it contains operating systems, an install CD or a live CD.

Add all disks belonging to the unknown virtual machine and call "guestfs_launch" in the usual way.

Then call "guestfs_inspect_os". This function uses other libguestfs calls and certain heuristics, and returns a list of operating systems that were found. An empty list means none were found. A single element is the root filesystem of the operating system. For dual- or multi-boot guests, multiple roots can be returned, each one corresponding to a separate operating system. (Multi-boot virtual machines are extremely rare in the world of virtualization, but since this scenario can happen, we have built libguestfs to deal with it.)

For each root, you can then call various "guestfs_inspect_get_*" functions to get additional details about that operating system. For example, call "guestfs_inspect_get_type" to return the string "windows" or "linux" for Windows and Linux-based operating systems respectively.

Un*x-like and Linux-based operating systems usually consist of several filesystems which are mounted at boot time (for example, a separate boot partition mounted on /boot). The inspection rules are able to detect how filesystems correspond to mount points. Call "guestfs_inspect_get_mountpoints" to get this mapping. It might return a hash table like this example:

 /boot => /dev/sda1
 /     => /dev/vg_guest/lv_root
 /usr  => /dev/vg_guest/lv_usr

The caller can then make calls to "guestfs_mount" to mount the filesystems as suggested.

Be careful to mount filesystems in the right order (eg. / before /usr). Sorting the keys of the hash by length, shortest first, should work.

Inspection currently only works for some common operating systems. Contributors are welcome to send patches for other operating systems that we currently cannot detect.

Encrypted disks must be opened before inspection. See "ENCRYPTED DISKS" for more details. The "guestfs_inspect_os" function just ignores any encrypted devices.

A note on the implementation: The call "guestfs_inspect_os" performs inspection and caches the results in the guest handle. Subsequent calls to "guestfs_inspect_get_*" return this cached information, but do not re-read the disks. If you change the content of the guest disks, you can redo inspection by calling "guestfs_inspect_os" again. ("guestfs_inspect_list_applications2" works a little differently from the other calls and does read the disks. See documentation for that function for details).

INSPECTING INSTALL DISKS

Libguestfs (since 1.9.4) can detect some install disks, install CDs, live CDs and more.

Further information is available about the operating system that can be installed using the regular inspection APIs like "guestfs_inspect_get_product_name", "guestfs_inspect_get_major_version" etc.

SPECIAL CONSIDERATIONS FOR WINDOWS GUESTS¶

Libguestfs can mount NTFS partitions. It does this using the http://www.ntfs-3g.org/ driver.

DRIVE LETTERS AND PATHS

DOS and Windows still use drive letters, and the filesystems are always treated as case insensitive by Windows itself, and therefore you might find a Windows configuration file referring to a path like "c:\windows\system32". When the filesystem is mounted in libguestfs, that directory might be referred to as /WINDOWS/System32.

Drive letter mappings can be found using inspection (see "INSPECTION" and "guestfs_inspect_get_drive_mappings")

Dealing with separator characters (backslash vs forward slash) is outside the scope of libguestfs, but usually a simple character replacement will work.

To resolve the case insensitivity of paths, call "guestfs_case_sensitive_path".

LONG FILENAMES ON NTFS

NTFS supports filenames up to 255 characters long. "Character" means a 2 byte UTF-16 codepoint which can encode the most common Unicode codepoints.

Most Linux filesystems support filenames up to 255 bytes. This means you may get an error:

 File name too long

when you copy a file from NTFS to a Linux filesystem if the name, when reencoded as UTF-8, would exceed 255 bytes in length.

This will most often happen when using non-ASCII names that are longer than ~127 characters (eg. Greek, Cyrillic) or longer than ~85 characters (Asian languages).

A workaround is not to try to store such long filenames on Linux native filesystems. Since the tar(1) format can store unlimited length filenames, keep the files in a tarball.

ACCESSING THE WINDOWS REGISTRY

Libguestfs also provides some help for decoding Windows Registry "hive" files, through a separate C library called hivex(3).

Before libguestfs 1.19.35 you had to download the hive file, operate on it locally using hivex, and upload it again. Since this version, we have included the major hivex APIs directly in the libguestfs API (see "guestfs_hivex_open"). This means that if you have opened a Windows guest, you can read and write the registry directly.

See also virt-win-reg(1).

SYMLINKS ON NTFS-3G FILESYSTEMS

Ntfs-3g tries to rewrite "Junction Points" and NTFS "symbolic links" to provide something which looks like a Linux symlink. The way it tries to do the rewriting is described here:

http://www.tuxera.com/community/ntfs-3g-advanced/junction-points-and-symbolic-links/

The essential problem is that ntfs-3g simply does not have enough information to do a correct job. NTFS links can contain drive letters and references to external device GUIDs that ntfs-3g has no way of resolving. It is almost certainly the case that libguestfs callers should ignore what ntfs-3g does (ie. don't use "guestfs_readlink" on NTFS volumes).

Instead if you encounter a symbolic link on an ntfs-3g filesystem, use "guestfs_lgetxattr" to read the "system.ntfs_reparse_data" extended attribute, and read the raw reparse data from that (you can find the format documented in various places around the web).

EXTENDED ATTRIBUTES ON NTFS-3G FILESYSTEMS

There are other useful extended attributes that can be read from ntfs-3g filesystems (using "guestfs_getxattr"). See:

http://www.tuxera.com/community/ntfs-3g-advanced/extended-attributes/

WINDOWS HIBERNATION AND WINDOWS 8 FAST STARTUP

Windows guests which have been hibernated (instead of fully shut down) cannot be mounted. This is a limitation of ntfs-3g. You will see an error like this:

 The disk contains an unclean file system (0, 0).
 Metadata kept in Windows cache, refused to mount.
 Failed to mount '/dev/sda2': Operation not permitted
 The NTFS partition is in an unsafe state. Please resume
 and shutdown Windows fully (no hibernation or fast
 restarting), or mount the volume read-only with the
 'ro' mount option.

In Windows 8, the shutdown button does not shut down the guest at all. Instead it usually hibernates the guest. This is known as "fast startup".

Some suggested workarounds are:

• Mount read-only (eg. "guestfs_mount_ro").
• On Windows 8, turn off fast startup. It is in the Control Panel → Power Options → Choose what the power buttons do → Change settings that are currently unavailable → Turn on fast startup.
• On Windows 7 and earlier, shut the guest off properly instead of hibernating it.

RESIZE2FS ERRORS¶

The "guestfs_resize2fs", "guestfs_resize2fs_size" and "guestfs_resize2fs_M" calls are used to resize ext2/3/4 filesystems.

The underlying program (resize2fs(8)) requires that the filesystem is clean and recently fsck'd before you can resize it. Also, if the resize operation fails for some reason, then you had to call fsck the filesystem again to fix it.

In libguestfs "lt" 1.17.14, you usually had to call "guestfs_e2fsck_f" before the resize. However, in "ge" 1.17.14, e2fsck(8) is called automatically before the resize, so you no longer need to do this.

The resize2fs(8) program can still fail, in which case it prints an error message similar to:

 Please run 'e2fsck -fy <device>' to fix the filesystem
 after the aborted resize operation.

You can do this by calling "guestfs_e2fsck" with the "forceall" option. However in the context of disk images, it is usually better to avoid this situation, eg. by rolling back to an earlier snapshot, or by copying and resizing and on failure going back to the original.

USING LIBGUESTFS WITH OTHER PROGRAMMING LANGUAGES¶

Although we don’t want to discourage you from using the C API, we will mention here that the same API is also available in other languages.

The API is broadly identical in all supported languages. This means that the C call "guestfs_add_drive_ro(g,file)" is "$g->add_drive_ro($file)" in Perl, "g.add_drive_ro(file)" in Python, and "g#add_drive_ro file" in OCaml. In other words, a straightforward, predictable isomorphism between each language.

Error messages are automatically transformed into exceptions if the language supports it.

We don’t try to "object orientify" parts of the API in OO languages, although contributors are welcome to write higher level APIs above what we provide in their favourite languages if they wish.

C++

You can use the guestfs.h header file from C++ programs. The C++ API is identical to the C API. C++ classes and exceptions are not used.

C#

The C# bindings are highly experimental. Please read the warnings at the top of csharp/Libguestfs.cs.

Erlang

See guestfs-erlang(3).

GObject

Experimental GObject bindings (with GObject Introspection support) are available.

See guestfs-gobject(3).

Go

See guestfs-golang(3).

Haskell

This language binding is working but incomplete:

Java

Full documentation is contained in the Javadoc which is distributed with libguestfs. For examples, see guestfs-java(3).

Lua

See guestfs-lua(3).

OCaml

See guestfs-ocaml(3).

Perl

See guestfs-perl(3) and Sys::Guestfs(3).

PHP

For documentation see "README-PHP" supplied with libguestfs sources or in the php-libguestfs package for your distribution.

The PHP binding only works correctly on 64 bit machines.

Python

See guestfs-python(3).

Ruby

See guestfs-ruby(3).

For JRuby, use the Java bindings.

shell scripts

See guestfish(1).

LIBGUESTFS GOTCHAS¶

http://en.wikipedia.org/wiki/Gotcha_(programming): "A feature of a system [...] that works in the way it is documented but is counterintuitive and almost invites mistakes."

Since we developed libguestfs and the associated tools, there are several things we would have designed differently, but are now stuck with for backwards compatibility or other reasons. If there is ever a libguestfs 2.0 release, you can expect these to change. Beware of them.

Read-only should be the default.

In guestfish(3), --ro should be the default, and you should have to specify --rw if you want to make changes to the image.

This would reduce the potential to corrupt live VM images.

Note that many filesystems change the disk when you just mount and unmount, even if you didn't perform any writes. You need to use "guestfs_add_drive_ro" to guarantee that the disk is not changed.

guestfish command line is hard to use.

guestfish disk.img doesn't do what people expect (open disk.img for examination). It tries to run a guestfish command disk.img which doesn't exist, so it fails. In earlier versions of guestfish the error message was also unintuitive, but we have corrected this since. Like the Bourne shell, we should have used "guestfish -c command" to run commands.

guestfish megabyte modifiers don’t work right on all commands

In recent guestfish you can use "1M" to mean 1 megabyte (and similarly for other modifiers). What guestfish actually does is to multiply the number part by the modifier part and pass the result to the C API. However this doesn't work for a few APIs which aren't expecting bytes, but are already expecting some other unit (eg. megabytes).

The most common is "guestfs_lvcreate". The guestfish command:

 lvcreate LV VG 100M
    

does not do what you might expect. Instead because "guestfs_lvcreate" is already expecting megabytes, this tries to create a 100 terabyte (100 megabytes * megabytes) logical volume. The error message you get from this is also a little obscure.

This could be fixed in the generator by specially marking parameters and return values which take bytes or other units.

Ambiguity between devices and paths

There is a subtle ambiguity in the API between a device name (eg. /dev/sdb2) and a similar pathname. A file might just happen to be called "sdb2" in the directory /dev (consider some non-Unix VM image).

In the current API we usually resolve this ambiguity by having two separate calls, for example "guestfs_checksum" and "guestfs_checksum_device". Some API calls are ambiguous and (incorrectly) resolve the problem by detecting if the path supplied begins with /dev/.

To avoid both the ambiguity and the need to duplicate some calls, we could make paths/devices into structured names. One way to do this would be to use a notation like grub ("hd(0,0)"), although nobody really likes this aspect of grub. Another way would be to use a structured type, equivalent to this OCaml type:

 type path = Path of string | Device of int | Partition of int * int
    

which would allow you to pass arguments like:

 Path "/foo/bar"
 Device 1            (* /dev/sdb, or perhaps /dev/sda *)
 Partition (1, 2)    (* /dev/sdb2 (or is it /dev/sda2 or /dev/sdb3?) *)
 Path "/dev/sdb2"    (* not a device *)
    

As you can see there are still problems to resolve even with this representation. Also consider how it might work in guestfish.

KEYS AND PASSPHRASES¶

Certain libguestfs calls take a parameter that contains sensitive key material, passed in as a C string.

In the future we would hope to change the libguestfs implementation so that keys are mlock(2)-ed into physical RAM, and thus can never end up in swap. However this is not done at the moment, because of the complexity of such an implementation.

Therefore you should be aware that any key parameter you pass to libguestfs might end up being written out to the swap partition. If this is a concern, scrub the swap partition or don't use libguestfs on encrypted devices.

MULTIPLE HANDLES AND MULTIPLE THREADS¶

All high-level libguestfs actions are synchronous. If you want to use libguestfs asynchronously then you must create a thread.

Threads in libguestfs ≥ 1.38

In libguestfs ≥ 1.38, each handle ("guestfs_h") contains a lock which is acquired automatically when you call a libguestfs function. The practical effect of this is you can call libguestfs functions with the same handle from multiple threads without needing to do any locking.

Also in libguestfs ≥ 1.38, the last error on the handle ("guestfs_last_error", "guestfs_last_errno") is stored in thread-local storage, so it is safe to write code like:

 if (guestfs_add_drive_ro (g, drive) == -1)
   fprintf (stderr, "error was: %s\n", guestfs_last_error (g));

even when other threads may be concurrently using the same handle "g".

Threads in libguestfs < 1.38

In libguestfs < 1.38, you must use the handle only from a single thread. Either use the handle exclusively from one thread, or provide your own mutex so that two threads cannot issue calls on the same handle at the same time. Even apparently innocent functions like "guestfs_get_trace" are not safe to be called from multiple threads without a mutex in libguestfs < 1.38.

Use "guestfs_set_identifier" to make it simpler to identify threads in trace output.

PATH¶

Libguestfs needs a supermin appliance, which it finds by looking along an internal path.

By default it looks for these in the directory "$libdir/guestfs" (eg. /usr/local/lib/guestfs or /usr/lib64/guestfs).

Use "guestfs_set_path" or set the environment variable "LIBGUESTFS_PATH" to change the directories that libguestfs will search in. The value is a colon-separated list of paths. The current directory is not searched unless the path contains an empty element or ".". For example "LIBGUESTFS_PATH=:/usr/lib/guestfs" would search the current directory and then /usr/lib/guestfs.

QEMU WRAPPERS¶

If you want to compile your own qemu, run qemu from a non-standard location, or pass extra arguments to qemu, then you can write a shell-script wrapper around qemu.

There is one important rule to remember: you must "exec qemu" as the last command in the shell script (so that qemu replaces the shell and becomes the direct child of the libguestfs-using program). If you don't do this, then the qemu process won't be cleaned up correctly.

Here is an example of a wrapper, where I have built my own copy of qemu from source:

 #!/bin/sh -
 qemudir=/home/rjones/d/qemu
 exec $qemudir/x86_64-softmmu/qemu-system-x86_64 -L $qemudir/pc-bios "$@"

Save this script as /tmp/qemu.wrapper (or wherever), "chmod +x", and then use it by setting the LIBGUESTFS_HV environment variable. For example:

 LIBGUESTFS_HV=/tmp/qemu.wrapper guestfish

Note that libguestfs also calls qemu with the -help and -version options in order to determine features.

Wrappers can also be used to edit the options passed to qemu. In the following example, the "-machine ..." option ("-machine" and the following argument) are removed from the command line and replaced with "-machine pc,accel=tcg". The while loop iterates over the options until it finds the right one to remove, putting the remaining options into the "args" array.

 #!/bin/bash -
 
 i=0
 while [ $# -gt 0 ]; do
     case "$1" in
     -machine)
         shift 2;;
     *)
         args[i]="$1"
         (( i++ ))
         shift ;;
     esac
 done
 
 exec qemu-kvm -machine pc,accel=tcg "${args[@]}"

BACKEND¶

The backend (previously known as the "attach method") controls how libguestfs creates and/or connects to the backend daemon, eg. by starting qemu directly, or using libvirt to manage an appliance, running User-Mode Linux, or connecting to an already running daemon.

You can set the backend by calling "guestfs_set_backend", or by setting the environment variable "LIBGUESTFS_BACKEND".

Possible backends are described below:

"direct"

"appliance"

Run qemu directly to launch an appliance.

"direct" and "appliance" are synonyms.

This is the ordinary method and normally the default, but see the note below.

"libvirt"

"libvirt:null"

"libvirt:URI"

Use libvirt to launch and manage the appliance.

"libvirt" causes libguestfs to choose a suitable URI for creating session guests. If using the libvirt backend, you almost always should use this.

"libvirt:null" causes libguestfs to use the "NULL" connection URI, which causes libvirt to try to guess what the user meant. You probably don't want to use this.

"libvirt:URI" uses URI as the libvirt connection URI (see http://libvirt.org/uri.html). The typical libvirt backend with a URI would be "libvirt:qemu:///session"

The libvirt backend supports more features, including sVirt.

"direct" is usually the default backend. However since libguestfs ≥ 1.19.24, libguestfs can be built with a different default by doing:

 ./configure --with-default-backend=...

To find out if libguestfs was compiled with a different default backend, do:

 unset LIBGUESTFS_BACKEND
 guestfish get-backend

BACKEND SETTINGS¶

Each backend can be configured by passing a list of strings. You can either call "guestfs_set_backend_settings" with a list of strings, or set the "LIBGUESTFS_BACKEND_SETTINGS" environment variable to a colon-separated list of strings (before creating the handle).

force_tcg

Using:

 export LIBGUESTFS_BACKEND_SETTINGS=force_tcg

will force the direct and libvirt backends to use TCG (software emulation) instead of KVM (hardware accelerated virtualization).

force_kvm

Using:

 export LIBGUESTFS_BACKEND_SETTINGS=force_kvm

will force the direct and libvirt backends to use KVM (hardware accelerated virtualization) instead of TCG (software emulation).

gdb

The direct backend supports:

 export LIBGUESTFS_BACKEND_SETTINGS=gdb

When this is set, qemu will not start running the appliance immediately. It will wait for you to connect to it using gdb:

 $ gdb
 (gdb) symbol-file /path/to/vmlinux
 (gdb) target remote tcp::1234
 (gdb) cont

You can then debug the appliance kernel, which is useful to debug boot failures (especially ones where there are no debug messages printed - tip: look in the kernel "log_buf").

On Fedora, install "kernel-debuginfo" for the "vmlinux" file (containing symbols). Make sure the symbols precisely match the kernel being used.

ABI GUARANTEE¶

We guarantee the libguestfs ABI (binary interface), for public, high-level actions as outlined in this section. Although we will deprecate some actions, for example if they get replaced by newer calls, we will keep the old actions forever. This allows you the developer to program in confidence against the libguestfs API.

BLOCK DEVICE NAMING¶

Libguestfs defines /dev/sd* as the standard naming scheme for devices passed to API calls. So /dev/sda means "the first device added by "guestfs_add_drive_opts"", and /dev/sdb3 means "the third partition on the second device".

Internally device names are sometimes translated, but this should not be visible at the API level.

DISK LABELS

In libguestfs ≥ 1.20, you can give a label to a disk when you add it, using the optional "label" parameter to "guestfs_add_drive_opts". (Note that disk labels are different from and not related to filesystem labels).

Not all versions of libguestfs support setting a disk label, and when it is supported, it is limited to 20 ASCII characters "[a-zA-Z]".

When you add a disk with a label, it can either be addressed using /dev/sd*, or using /dev/disk/guestfs/label. Partitions on the disk can be addressed using /dev/disk/guestfs/labelpartnum.

Listing devices ("guestfs_list_devices") and partitions ("guestfs_list_partitions") returns the block device names. However you can use "guestfs_list_disk_labels" to map disk labels to block device and partition names.

NULL DISKS¶

When adding a disk using, eg., "guestfs_add_drive", you can set the filename to "/dev/null". This string is treated specially by libguestfs, causing it to add a "null disk".

A null disk has the following properties:

• A null disk will appear as a normal device, eg. in calls to "guestfs_list_devices".
• You may add "/dev/null" multiple times.
• You should not try to access a null disk in any way. For example, you shouldn't try to read it or mount it.

Null disks are used for three main purposes:

1.

Performance testing of libguestfs (see guestfs-performance(1)).

2.

The internal test suite.

3.

If you want to use libguestfs APIs that don’t refer to disks, since libguestfs requires that at least one disk is added, you should add a null disk.

For example, to test if a feature is available, use code like this:

 guestfs_h *g;
 char **groups = [ "btrfs", NULL ];
 
 g = guestfs_create ();
 guestfs_add_drive (g, "/dev/null");
 guestfs_launch (g);
 if (guestfs_available (g, groups) == 0) {
   // group(s) are available
 } else {
   // group(s) are not available
 }
 guestfs_close (g);
    

DISK IMAGE FORMATS¶

Virtual disks come in a variety of formats. Some common formats are listed below.

Note that libguestfs itself is not responsible for handling the disk format: this is done using qemu(1). If support for a particular format is missing or broken, this has to be fixed in qemu.

COMMON VIRTUAL DISK IMAGE FORMATS

raw

Raw format is simply a dump of the sequential bytes of the virtual hard disk. There is no header, container, compression or processing of any sort.

Since raw format requires no translation to read or write, it is both fast and very well supported by qemu and all other hypervisors. You can consider it to be a universal format that any hypervisor can access.

Raw format files are not compressed and so take up the full space of the original disk image even when they are empty. A variation (on Linux/Unix at least) is to not store ranges of all-zero bytes by storing the file as a sparse file. This "variant format" is sometimes called raw sparse. Many utilities, including virt-sparsify(1), can make raw disk images sparse.

qcow2

Qcow2 is the native disk image format used by qemu. Internally it uses a two-level directory structure so that only blocks containing data are stored in the file. It also has many other features such as compression, snapshots and backing files.

There are at least two distinct variants of this format, although qemu (and hence libguestfs) handles both transparently to the user.

vmdk

VMDK is VMware’s native disk image format. There are many variations. Modern qemu (hence libguestfs) supports most variations, but you should be aware that older versions of qemu had some very bad data-corrupting bugs in this area.

Note that VMware ESX exposes files with the name guest-flat.vmdk. These are not VMDK. They are raw format files which happen to have a ".vmdk" extension.

vdi

VDI is VirtualBox’s native disk image format. Qemu (hence libguestfs) has generally good support for this.

vpc

vhd

VPC (old) and VHD (modern) are the native disk image format of Microsoft (and previously, Connectix) Virtual PC and Hyper-V.

Obsolete formats

The following formats are obsolete and should not be used: qcow (aka qcow1), cow, bochs.

DETECTING THE FORMAT OF A DISK IMAGE

Firstly note there is a security issue with auto-detecting the format of a disk image. It may or may not apply in your use case. Read "CVE-2010-3851" below.

Libguestfs offers an API to get the format of a disk image ("guestfs_disk_format"), and it is safest to use this.

Don’t be tempted to try parsing the text / human-readable output of "qemu-img" since it cannot be parsed reliably and securely. Also do not use the "file" command since the output of that changes over time.

guestfs_h *¶

"guestfs_h" is the opaque type representing a connection handle. Create a handle by calling "guestfs_create" or "guestfs_create_flags". Call "guestfs_close" to free the handle and release all resources used.

For information on using multiple handles and threads, see the section "MULTIPLE HANDLES AND MULTIPLE THREADS" above.

guestfs_create¶

 guestfs_h *guestfs_create (void);

Create a connection handle.

On success this returns a non-NULL pointer to a handle. On error it returns NULL.

You have to "configure" the handle after creating it. This includes calling "guestfs_add_drive_opts" (or one of the equivalent calls) on the handle at least once.

After configuring the handle, you have to call "guestfs_launch".

You may also want to configure error handling for the handle. See the "ERROR HANDLING" section below.

guestfs_create_flags¶

 guestfs_h *guestfs_create_flags (unsigned flags [, ...]);

Create a connection handle, supplying extra flags and extra arguments to control how the handle is created.

On success this returns a non-NULL pointer to a handle. On error it returns NULL.

"guestfs_create" is equivalent to calling guestfs_create_flags(0).

The following flags may be logically ORed together. (Currently no extra arguments are used).

"GUESTFS_CREATE_NO_ENVIRONMENT"

Don’t parse any environment variables (such as "LIBGUESTFS_DEBUG" etc).

You can call "guestfs_parse_environment" or "guestfs_parse_environment_list" afterwards to parse environment variables. Alternately, don't call these functions if you want the handle to be unaffected by environment variables. See the example below.

The default (if this flag is not given) is to implicitly call "guestfs_parse_environment".

"GUESTFS_CREATE_NO_CLOSE_ON_EXIT"

Don’t try to close the handle in an atexit(3) handler if the program exits without explicitly closing the handle.

The default (if this flag is not given) is to install such an atexit handler.

USING "GUESTFS_CREATE_NO_ENVIRONMENT"

You might use "GUESTFS_CREATE_NO_ENVIRONMENT" and an explicit call to "guestfs_parse_environment" like this:

 guestfs_h *g;
 int r;
 
 g = guestfs_create_flags (GUESTFS_CREATE_NO_ENVIRONMENT);
 if (!g) {
   perror ("guestfs_create_flags");
   exit (EXIT_FAILURE);
 }
 r = guestfs_parse_environment (g);
 if (r == -1)
   exit (EXIT_FAILURE);

Or to create a handle which is unaffected by environment variables, omit the call to "guestfs_parse_environment" from the above code.

The above code has another advantage which is that any errors from parsing the environment are passed through the error handler, whereas "guestfs_create" prints errors on stderr and ignores them.

guestfs_close¶

 void guestfs_close (guestfs_h *g);

This closes the connection handle and frees up all resources used. If a close callback was set on the handle, then it is called.

The correct way to close the handle is:

 if (guestfs_shutdown (g) == -1) {
   /* handle write errors here */
 }
 guestfs_close (g);

"guestfs_shutdown" is only needed if all of the following are true:

1.

one or more disks were added in read-write mode, and

2.

guestfs_launch was called, and

3.

you made some changes, and

4.

you have a way to handle write errors (eg. by exiting with an error code or reporting something to the user).

guestfs_last_error¶

 const char *guestfs_last_error (guestfs_h *g);

This returns the last error message that happened on "g". If there has not been an error since the handle was created, then this returns "NULL".

Note the returned string does not have a newline character at the end. Most error messages are single lines. Some are split over multiple lines and contain "\n" characters within the string but not at the end.

The lifetime of the returned string is until the next error occurs on the same handle, or "guestfs_close" is called. If you need to keep it longer, copy it.

guestfs_last_errno¶

 int guestfs_last_errno (guestfs_h *g);

This returns the last error number (errno) that happened on "g".

If successful, an errno integer not equal to zero is returned.

In many cases the special errno "ENOTSUP" is returned if you tried to call a function or use a feature which is not supported.

If no error number is available, this returns 0. This call can return 0 in three situations:

1.

There has not been any error on the handle.

2.

There has been an error but the errno was meaningless. This corresponds to the case where the error did not come from a failed system call, but for some other reason.

3.

There was an error from a failed system call, but for some reason the errno was not captured and returned. This usually indicates a bug in libguestfs.

Libguestfs tries to convert the errno from inside the appliance into a corresponding errno for the caller (not entirely trivial: the appliance might be running a completely different operating system from the library and error numbers are not standardized across Un*xen). If this could not be done, then the error is translated to "EINVAL". In practice this should only happen in very rare circumstances.

guestfs_set_error_handler¶

 typedef void (*guestfs_error_handler_cb) (guestfs_h *g,
                                           void *opaque,
                                           const char *msg);
 void guestfs_set_error_handler (guestfs_h *g,
                                 guestfs_error_handler_cb cb,
                                 void *opaque);

The callback "cb" will be called if there is an error. The parameters passed to the callback are an opaque data pointer and the error message string.

"errno" is not passed to the callback. To get that the callback must call "guestfs_last_errno".

Note that the message string "msg" is freed as soon as the callback function returns, so if you want to stash it somewhere you must make your own copy.

The default handler prints messages on "stderr".

If you set "cb" to "NULL" then no handler is called.

guestfs_get_error_handler¶

 guestfs_error_handler_cb guestfs_get_error_handler (guestfs_h *g,
                                                     void **opaque_rtn);

Returns the current error handler callback.

guestfs_push_error_handler¶

 void guestfs_push_error_handler (guestfs_h *g,
                                  guestfs_error_handler_cb cb,
                                  void *opaque);

This is the same as "guestfs_set_error_handler", except that the old error handler is stashed away in a stack inside the handle. You can restore the previous error handler by calling "guestfs_pop_error_handler".

Use the following code to temporarily disable errors around a function:

 guestfs_push_error_handler (g, NULL, NULL);
 guestfs_mkdir (g, "/foo"); /* We don't care if this fails. */
 guestfs_pop_error_handler (g);

guestfs_pop_error_handler¶

 void guestfs_pop_error_handler (guestfs_h *g);

Restore the previous error handler (see "guestfs_push_error_handler").

If you pop the stack too many times, then the default error handler is restored.

guestfs_set_out_of_memory_handler¶

 typedef void (*guestfs_abort_cb) (void);
 void guestfs_set_out_of_memory_handler (guestfs_h *g,
                                         guestfs_abort_cb);

The callback "cb" will be called if there is an out of memory situation. Note this callback must not return.

The default is to call abort(3).

You cannot set "cb" to "NULL". You can’t ignore out of memory situations.

guestfs_get_out_of_memory_handler¶

 guestfs_abort_fn guestfs_get_out_of_memory_handler (guestfs_h *g);

This returns the current out of memory handler.

guestfs_acl_delete_def_file¶

 int
 guestfs_acl_delete_def_file (guestfs_h *g,
                              const char *dir);

This function deletes the default POSIX Access Control List (ACL) attached to directory "dir".

This function returns 0 on success or -1 on error.

This function depends on the feature "acl". See also "guestfs_feature_available".

(Added in 1.19.63)

guestfs_acl_get_file¶

 char *
 guestfs_acl_get_file (guestfs_h *g,
                       const char *path,
                       const char *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.

This function returns a string, or NULL on error. The caller must free the returned string after use.

This function depends on the feature "acl". See also "guestfs_feature_available".

(Added in 1.19.63)

guestfs_acl_set_file¶

 int
 guestfs_acl_set_file (guestfs_h *g,
                       const char *path,
                       const char *acltype,
                       const char *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 "guestfs_aug_init").

This function returns 0 on success or -1 on error.

This function depends on the feature "acl". See also "guestfs_feature_available".

(Added in 1.19.63)

guestfs_add_cdrom¶

 int
 guestfs_add_cdrom (guestfs_h *g,
                    const char *filename);

This function is deprecated. In new code, use the "guestfs_add_drive_ro" 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.

This function adds a virtual CD-ROM disk image to the guest.

The image is added as read-only drive, so this function is equivalent of "guestfs_add_drive_ro".

This function returns 0 on success or -1 on error.

(Added in 0.3)

guestfs_add_domain¶

 int
 guestfs_add_domain (guestfs_h *g,
                     const char *dom,
                     ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_ADD_DOMAIN_LIBVIRTURI, const char *libvirturi,
 GUESTFS_ADD_DOMAIN_READONLY, int readonly,
 GUESTFS_ADD_DOMAIN_IFACE, const char *iface,
 GUESTFS_ADD_DOMAIN_LIVE, int live,
 GUESTFS_ADD_DOMAIN_ALLOWUUID, int allowuuid,
 GUESTFS_ADD_DOMAIN_READONLYDISK, const char *readonlydisk,
 GUESTFS_ADD_DOMAIN_CACHEMODE, const char *cachemode,
 GUESTFS_ADD_DOMAIN_DISCARD, const char *discard,
 GUESTFS_ADD_DOMAIN_COPYONREAD, int copyonread,

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 "guestfs_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 https://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 https://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 is ignored in libguestfs ≥ 1.48.

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.

If present, the value of "logical_block_size" attribute of <blockio/> tag in libvirt XML will be passed as "blocksize" parameter to "guestfs_add_drive_opts".

The other optional parameters are passed directly through to "guestfs_add_drive_opts".

On error this function returns -1.

(Added in 1.7.4)

guestfs_add_domain_va¶

 int
 guestfs_add_domain_va (guestfs_h *g,
                        const char *dom,
                        va_list args);

This is the "va_list variant" of "guestfs_add_domain".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_add_domain_argv¶

 int
 guestfs_add_domain_argv (guestfs_h *g,
                          const char *dom,
                          const struct guestfs_add_domain_argv *optargs);

This is the "argv variant" of "guestfs_add_domain".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_add_drive¶

 int
 guestfs_add_drive (guestfs_h *g,
                    const char *filename);

This function is provided for backwards compatibility with earlier versions of libguestfs. It simply calls "guestfs_add_drive_opts" with no optional arguments.

(Added in 0.3)

guestfs_add_drive_opts¶

 int
 guestfs_add_drive_opts (guestfs_h *g,
                         const char *filename,
                         ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_ADD_DRIVE_OPTS_READONLY, int readonly,
 GUESTFS_ADD_DRIVE_OPTS_FORMAT, const char *format,
 GUESTFS_ADD_DRIVE_OPTS_IFACE, const char *iface,
 GUESTFS_ADD_DRIVE_OPTS_NAME, const char *name,
 GUESTFS_ADD_DRIVE_OPTS_LABEL, const char *label,
 GUESTFS_ADD_DRIVE_OPTS_PROTOCOL, const char *protocol,
 GUESTFS_ADD_DRIVE_OPTS_SERVER, char *const *server,
 GUESTFS_ADD_DRIVE_OPTS_USERNAME, const char *username,
 GUESTFS_ADD_DRIVE_OPTS_SECRET, const char *secret,
 GUESTFS_ADD_DRIVE_OPTS_CACHEMODE, const char *cachemode,
 GUESTFS_ADD_DRIVE_OPTS_DISCARD, const char *discard,
 GUESTFS_ADD_DRIVE_OPTS_COPYONREAD, int copyonread,
 GUESTFS_ADD_DRIVE_OPTS_BLOCKSIZE, int blocksize,

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 "guestfs_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.

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".

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 "guestfs_add_drive" or "guestfs_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 "guestfs_add_drive_with_if" call (q.v.)

"name"

This field used to be passed as a hint for guest inspection, but it is no longer used.

"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".

"protocol"

The optional protocol argument can be used to select an alternate source protocol.

See also: "REMOTE STORAGE".

"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  Exactly one
 iscsi          Exactly one
 nbd            Exactly one
 rbd            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" and "ssh" 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. It must be base64 encoded.

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:

"discard"

Enable or disable discard (a.k.a. trim or unmap) support on this drive. If enabled, operations such as "guestfs_fstrim" will be able to discard / make thin / punch holes in the underlying host file or device.

Possible discard settings are:

"copyonread"

The boolean parameter "copyonread" enables copy-on-read support. This only affects disk formats which have backing files, and causes reads to be stored in the overlay layer, speeding up multiple reads of the same area of disk.

The default is false.

"blocksize"

This parameter sets the sector size of the disk. Possible values are 512 (the default if the parameter is omitted) or 4096. Use 4096 when handling an "Advanced Format" disk that uses 4K sector size (https://en.wikipedia.org/wiki/Advanced_Format).

Only a subset of the backends support this parameter (currently only the libvirt and direct backends do).

This function returns 0 on success or -1 on error.

(Added in 0.3)

guestfs_add_drive_opts_va¶

 int
 guestfs_add_drive_opts_va (guestfs_h *g,
                            const char *filename,
                            va_list args);

This is the "va_list variant" of "guestfs_add_drive_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_add_drive_opts_argv¶

 int
 guestfs_add_drive_opts_argv (guestfs_h *g,
                              const char *filename,
                              const struct guestfs_add_drive_opts_argv *optargs);

This is the "argv variant" of "guestfs_add_drive_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_add_drive_ro¶

 int
 guestfs_add_drive_ro (guestfs_h *g,
                       const char *filename);

This function is the equivalent of calling "guestfs_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.

This function returns 0 on success or -1 on error.

(Added in 1.0.38)

guestfs_add_drive_ro_with_if¶

 int
 guestfs_add_drive_ro_with_if (guestfs_h *g,
                               const char *filename,
                               const char *iface);

This function is deprecated. In new code, use the "guestfs_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.

This is the same as "guestfs_add_drive_ro" but it allows you to specify the QEMU interface emulation to use at run time. Both the direct and the libvirt backends ignore "iface".

This function returns 0 on success or -1 on error.

(Added in 1.0.84)

guestfs_add_drive_scratch¶

 int
 guestfs_add_drive_scratch (guestfs_h *g,
                            int64_t size,
                            ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_ADD_DRIVE_SCRATCH_NAME, const char *name,
 GUESTFS_ADD_DRIVE_SCRATCH_LABEL, const char *label,
 GUESTFS_ADD_DRIVE_SCRATCH_BLOCKSIZE, int blocksize,

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", "label" and "blocksize" are passed through to "guestfs_add_drive_opts".

This function returns 0 on success or -1 on error.

(Added in 1.23.10)

guestfs_add_drive_scratch_va¶

 int
 guestfs_add_drive_scratch_va (guestfs_h *g,
                               int64_t size,
                               va_list args);

This is the "va_list variant" of "guestfs_add_drive_scratch".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_add_drive_scratch_argv¶

 int
 guestfs_add_drive_scratch_argv (guestfs_h *g,
                                 int64_t size,
                                 const struct guestfs_add_drive_scratch_argv *optargs);

This is the "argv variant" of "guestfs_add_drive_scratch".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_add_drive_with_if¶

 int
 guestfs_add_drive_with_if (guestfs_h *g,
                            const char *filename,
                            const char *iface);

This function is deprecated. In new code, use the "guestfs_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.

This is the same as "guestfs_add_drive" but it allows you to specify the QEMU interface emulation to use at run time. Both the direct and the libvirt backends ignore "iface".

This function returns 0 on success or -1 on error.

(Added in 1.0.84)

guestfs_add_libvirt_dom¶

 int
 guestfs_add_libvirt_dom (guestfs_h *g,
                          void * /* really virDomainPtr */ dom,
                          ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_ADD_LIBVIRT_DOM_READONLY, int readonly,
 GUESTFS_ADD_LIBVIRT_DOM_IFACE, const char *iface,
 GUESTFS_ADD_LIBVIRT_DOM_LIVE, int live,
 GUESTFS_ADD_LIBVIRT_DOM_READONLYDISK, const char *readonlydisk,
 GUESTFS_ADD_LIBVIRT_DOM_CACHEMODE, const char *cachemode,
 GUESTFS_ADD_LIBVIRT_DOM_DISCARD, const char *discard,
 GUESTFS_ADD_LIBVIRT_DOM_COPYONREAD, int copyonread,

This function adds the disk(s) attached to the libvirt domain "dom". It works by requesting the domain XML from libvirt, parsing it for disks, and calling "guestfs_add_drive_opts" on each one.

In the C API we declare "void *dom", but really it has type "virDomainPtr dom". This is so we don't need <libvirt.h>.

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 https://libvirt.org/remote.html) will fail unless those disks are accessible via the same device path locally too.

The optional "live" flag is ignored in libguestfs ≥ 1.48.

The optional "readonlydisk" parameter controls what we do for disks which are marked <readonly/> in the libvirt XML. See "guestfs_add_domain" for possible values.

If present, the value of "logical_block_size" attribute of <blockio/> tag in libvirt XML will be passed as "blocksize" parameter to "guestfs_add_drive_opts".

The other optional parameters are passed directly through to "guestfs_add_drive_opts".

On error this function returns -1.

(Added in 1.29.14)

guestfs_add_libvirt_dom_va¶

 int
 guestfs_add_libvirt_dom_va (guestfs_h *g,
                             void * /* really virDomainPtr */ dom,
                             va_list args);

This is the "va_list variant" of "guestfs_add_libvirt_dom".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_add_libvirt_dom_argv¶

 int
 guestfs_add_libvirt_dom_argv (guestfs_h *g,
                               void * /* really virDomainPtr */ dom,
                               const struct guestfs_add_libvirt_dom_argv *optargs);

This is the "argv variant" of "guestfs_add_libvirt_dom".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_aug_clear¶

 int
 guestfs_aug_clear (guestfs_h *g,
                    const char *augpath);

Set the value associated with "path" to "NULL". This is the same as the augtool(1) "clear" command.

This function returns 0 on success or -1 on error.

(Added in 1.3.4)

guestfs_aug_close¶

 int
 guestfs_aug_close (guestfs_h *g);

Close the current Augeas handle and free up any resources used by it. After calling this, you have to call "guestfs_aug_init" again before you can use any other Augeas functions.

This function returns 0 on success or -1 on error.

(Added in 0.7)

guestfs_aug_defnode¶

 struct guestfs_int_bool *
 guestfs_aug_defnode (guestfs_h *g,
                      const char *name,
                      const char *expr,
                      const char *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 "guestfs_aug_set" "expr", "val". "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.

This function returns a "struct guestfs_int_bool *", or NULL if there was an error. The caller must call "guestfs_free_int_bool" after use.

(Added in 0.7)

guestfs_aug_defvar¶

 int
 guestfs_aug_defvar (guestfs_h *g,
                     const char *name,
                     const char *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.

On error this function returns -1.

(Added in 0.7)

guestfs_aug_get¶

 char *
 guestfs_aug_get (guestfs_h *g,
                  const char *augpath);

Look up the value associated with "path". If "path" matches exactly one node, the "value" is returned.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 0.7)

guestfs_aug_init¶

 int
 guestfs_aug_init (guestfs_h *g,
                   const char *root,
                   int 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 "guestfs_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 "guestfs_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 "guestfs_aug_init".

To close the handle, you can call "guestfs_aug_close".

To find out more about Augeas, see http://augeas.net/.

This function returns 0 on success or -1 on error.

(Added in 0.7)

guestfs_aug_insert¶

 int
 guestfs_aug_insert (guestfs_h *g,
                     const char *augpath,
                     const char *label,
                     int 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]".

This function returns 0 on success or -1 on error.

(Added in 0.7)

guestfs_aug_label¶

 char *
 guestfs_aug_label (guestfs_h *g,
                    const char *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.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.23.14)

guestfs_aug_load¶

 int
 guestfs_aug_load (guestfs_h *g);

Load files into the tree.

See "aug_load" in the Augeas documentation for the full gory details.

This function returns 0 on success or -1 on error.

(Added in 0.7)

guestfs_aug_ls¶

 char **
 guestfs_aug_ls (guestfs_h *g,
                 const char *augpath);

This is just a shortcut for listing "guestfs_aug_match" "path/*" and sorting the resulting nodes into alphabetical order.

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

(Added in 0.8)

guestfs_aug_match¶

 char **
 guestfs_aug_match (guestfs_h *g,
                    const char *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.

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

(Added in 0.7)

guestfs_aug_mv¶

 int
 guestfs_aug_mv (guestfs_h *g,
                 const char *src,
                 const char *dest);

Move the node "src" to "dest". "src" must match exactly one node. "dest" is overwritten if it exists.

This function returns 0 on success or -1 on error.

(Added in 0.7)

guestfs_aug_rm¶

 int
 guestfs_aug_rm (guestfs_h *g,
                 const char *augpath);

Remove "path" and all of its children.

On success this returns the number of entries which were removed.

On error this function returns -1.

(Added in 0.7)

guestfs_aug_save¶

 int
 guestfs_aug_save (guestfs_h *g);

This writes all pending changes to disk.

The flags which were passed to "guestfs_aug_init" affect exactly how files are saved.

This function returns 0 on success or -1 on error.

(Added in 0.7)

guestfs_aug_set¶

 int
 guestfs_aug_set (guestfs_h *g,
                  const char *augpath,
                  const char *val);

Set the value associated with "augpath" 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 "guestfs_aug_clear" call.

This function returns 0 on success or -1 on error.

(Added in 0.7)

guestfs_aug_setm¶

 int
 guestfs_aug_setm (guestfs_h *g,
                   const char *base,
                   const char *sub,
                   const char *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.

On error this function returns -1.

(Added in 1.23.14)

guestfs_aug_transform¶

 int
 guestfs_aug_transform (guestfs_h *g,
                        const char *lens,
                        const char *file,
                        ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_AUG_TRANSFORM_REMOVE, int remove,

Add an Augeas transformation for the specified "lens" so it can handle "file".

If "remove" is true ("false" by default), then the transformation is removed.

This function returns 0 on success or -1 on error.

(Added in 1.35.2)

guestfs_aug_transform_va¶

 int
 guestfs_aug_transform_va (guestfs_h *g,
                           const char *lens,
                           const char *file,
                           va_list args);

This is the "va_list variant" of "guestfs_aug_transform".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_aug_transform_argv¶

 int
 guestfs_aug_transform_argv (guestfs_h *g,
                             const char *lens,
                             const char *file,
                             const struct guestfs_aug_transform_argv *optargs);

This is the "argv variant" of "guestfs_aug_transform".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_available¶

 int
 guestfs_available (guestfs_h *g,
                    char *const *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". You can also fetch this list at runtime by calling "guestfs_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:

• "guestfs_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 "guestfs_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 "guestfs_version".

See also "guestfs_filesystem_available".

This function returns 0 on success or -1 on error.

(Added in 1.0.80)

guestfs_available_all_groups¶

 char **
 guestfs_available_all_groups (guestfs_h *g);

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 "guestfs_available" / "guestfs_feature_available" on each member of the returned list.

See also "guestfs_available", "guestfs_feature_available" and "AVAILABILITY".

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

(Added in 1.3.15)

guestfs_base64_in¶

 int
 guestfs_base64_in (guestfs_h *g,
                    const char *base64file,
                    const char *filename);

This command uploads base64-encoded data from "base64file" to filename.

This function returns 0 on success or -1 on error.

(Added in 1.3.5)

guestfs_base64_out¶

 int
 guestfs_base64_out (guestfs_h *g,
                     const char *filename,
                     const char *base64file);

This command downloads the contents of filename, writing it out to local file "base64file" encoded as base64.

This function returns 0 on success or -1 on error.

(Added in 1.3.5)

guestfs_blkdiscard¶

 int
 guestfs_blkdiscard (guestfs_h *g,
                     const char *device);

This discards all blocks on the block device "device", giving the free space back to the host.

This operation requires support in libguestfs, 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. You must also set the "discard" attribute on the underlying drive (see "guestfs_add_drive_opts").

This function returns 0 on success or -1 on error.

This function depends on the feature "blkdiscard". See also "guestfs_feature_available".

(Added in 1.25.44)

guestfs_blkdiscardzeroes¶

 int
 guestfs_blkdiscardzeroes (guestfs_h *g,
                           const char *device);

This call returns true if blocks on "device" that have been discarded by a call to "guestfs_blkdiscard" are returned as blocks of zero bytes when read the next time.

If it returns false, then it may be that discarded blocks are read as stale or random data.

This function returns a C truth value on success or -1 on error.

This function depends on the feature "blkdiscardzeroes". See also "guestfs_feature_available".

(Added in 1.25.44)

guestfs_blkid¶

 char **
 guestfs_blkid (guestfs_h *g,
                const char *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".

This function returns a NULL-terminated array of strings, or NULL if there was an error. The array of strings will always have length "2n+1", where "n" keys and values alternate, followed by the trailing NULL entry. The caller must free the strings and the array after use.

(Added in 1.15.9)

guestfs_blockdev_flushbufs¶

 int
 guestfs_blockdev_flushbufs (guestfs_h *g,
                             const char *device);

This tells the kernel to flush internal buffers associated with "device".

This uses the blockdev(8) command.

This function returns 0 on success or -1 on error.

(Added in 1.9.3)

guestfs_blockdev_getbsz¶

 int
 guestfs_blockdev_getbsz (guestfs_h *g,
                          const char *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.

On error this function returns -1.

(Added in 1.9.3)

guestfs_blockdev_getro¶

 int
 guestfs_blockdev_getro (guestfs_h *g,
                         const char *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.

This function returns a C truth value on success or -1 on error.

(Added in 1.9.3)

guestfs_blockdev_getsize64¶

 int64_t
 guestfs_blockdev_getsize64 (guestfs_h *g,
                             const char *device);

This returns the size of the device in bytes.

See also "guestfs_blockdev_getsz".

This uses the blockdev(8) command.

On error this function returns -1.

(Added in 1.9.3)

guestfs_blockdev_getss¶

 int
 guestfs_blockdev_getss (guestfs_h *g,
                         const char *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 "guestfs_blockdev_getsz" for that).

This uses the blockdev(8) command.

On error this function returns -1.

(Added in 1.9.3)

guestfs_blockdev_getsz¶

 int64_t
 guestfs_blockdev_getsz (guestfs_h *g,
                         const char *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 "guestfs_blockdev_getss" for the real sector size of the device, and "guestfs_blockdev_getsize64" for the more useful size in bytes.

This uses the blockdev(8) command.

On error this function returns -1.

(Added in 1.9.3)

guestfs_blockdev_rereadpt¶

 int
 guestfs_blockdev_rereadpt (guestfs_h *g,
                            const char *device);

Reread the partition table on "device".

This uses the blockdev(8) command.

This function returns 0 on success or -1 on error.

(Added in 1.9.3)

guestfs_blockdev_setbsz¶

 int
 guestfs_blockdev_setbsz (guestfs_h *g,
                          const char *device,
                          int blocksize);

This function is deprecated. There is no replacement. Consult the API documentation in guestfs(3) for further information.

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.

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 "guestfs_mkfs".

This function returns 0 on success or -1 on error.

(Added in 1.9.3)

guestfs_blockdev_setra¶

 int
 guestfs_blockdev_setra (guestfs_h *g,
                         const char *device,
                         int sectors);

Set readahead (in 512-byte sectors) for the device.

This uses the blockdev(8) command.

This function returns 0 on success or -1 on error.

(Added in 1.29.10)

guestfs_blockdev_setro¶

 int
 guestfs_blockdev_setro (guestfs_h *g,
                         const char *device);

Sets the block device named "device" to read-only.

This uses the blockdev(8) command.

This function returns 0 on success or -1 on error.

(Added in 1.9.3)

guestfs_blockdev_setrw¶

 int
 guestfs_blockdev_setrw (guestfs_h *g,
                         const char *device);

Sets the block device named "device" to read-write.

This uses the blockdev(8) command.

This function returns 0 on success or -1 on error.

(Added in 1.9.3)

guestfs_btrfs_balance_cancel¶

 int
 guestfs_btrfs_balance_cancel (guestfs_h *g,
                               const char *path);

Cancel a running balance on a btrfs filesystem.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.22)

guestfs_btrfs_balance_pause¶

 int
 guestfs_btrfs_balance_pause (guestfs_h *g,
                              const char *path);

Pause a running balance on a btrfs filesystem.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.22)

guestfs_btrfs_balance_resume¶

 int
 guestfs_btrfs_balance_resume (guestfs_h *g,
                               const char *path);

Resume a paused balance on a btrfs filesystem.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.22)

guestfs_btrfs_balance_status¶

 struct guestfs_btrfsbalance *
 guestfs_btrfs_balance_status (guestfs_h *g,
                               const char *path);

Show the status of a running or paused balance on a btrfs filesystem.

This function returns a "struct guestfs_btrfsbalance *", or NULL if there was an error. The caller must call "guestfs_free_btrfsbalance" after use.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.26)

guestfs_btrfs_device_add¶

 int
 guestfs_btrfs_device_add (guestfs_h *g,
                           char *const *devices,
                           const char *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.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.17.35)

guestfs_btrfs_device_delete¶

 int
 guestfs_btrfs_device_delete (guestfs_h *g,
                              char *const *devices,
                              const char *fs);

Remove the "devices" from the btrfs filesystem mounted at "fs". If "devices" is an empty list, this does nothing.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.17.35)

guestfs_btrfs_filesystem_balance¶

 int
 guestfs_btrfs_filesystem_balance (guestfs_h *g,
                                   const char *fs);

Balance the chunks in the btrfs filesystem mounted at "fs" across the underlying devices.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.17.35)

guestfs_btrfs_filesystem_defragment¶

 int
 guestfs_btrfs_filesystem_defragment (guestfs_h *g,
                                      const char *path,
                                      ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_BTRFS_FILESYSTEM_DEFRAGMENT_FLUSH, int flush,
 GUESTFS_BTRFS_FILESYSTEM_DEFRAGMENT_COMPRESS, const char *compress,

Defragment a file or directory on a btrfs filesystem. compress is one of zlib or lzo.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.22)

guestfs_btrfs_filesystem_defragment_va¶

 int
 guestfs_btrfs_filesystem_defragment_va (guestfs_h *g,
                                         const char *path,
                                         va_list args);

This is the "va_list variant" of "guestfs_btrfs_filesystem_defragment".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_btrfs_filesystem_defragment_argv¶

 int
 guestfs_btrfs_filesystem_defragment_argv (guestfs_h *g,
                                           const char *path,
                                           const struct guestfs_btrfs_filesystem_defragment_argv *optargs);

This is the "argv variant" of "guestfs_btrfs_filesystem_defragment".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_btrfs_filesystem_resize¶

 int
 guestfs_btrfs_filesystem_resize (guestfs_h *g,
                                  const char *mountpoint,
                                  ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_BTRFS_FILESYSTEM_RESIZE_SIZE, int64_t 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).

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.11.17)

guestfs_btrfs_filesystem_resize_va¶

 int
 guestfs_btrfs_filesystem_resize_va (guestfs_h *g,
                                     const char *mountpoint,
                                     va_list args);

This is the "va_list variant" of "guestfs_btrfs_filesystem_resize".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_btrfs_filesystem_resize_argv¶

 int
 guestfs_btrfs_filesystem_resize_argv (guestfs_h *g,
                                       const char *mountpoint,
                                       const struct guestfs_btrfs_filesystem_resize_argv *optargs);

This is the "argv variant" of "guestfs_btrfs_filesystem_resize".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_btrfs_filesystem_show¶

 char **
 guestfs_btrfs_filesystem_show (guestfs_h *g,
                                const char *device);

Show all the devices where the filesystems in "device" is spanned over.

If not all the devices for the filesystems are present, then this function fails and the "errno" is set to "ENODEV".

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.33.29)

guestfs_btrfs_filesystem_sync¶

 int
 guestfs_btrfs_filesystem_sync (guestfs_h *g,
                                const char *fs);

Force sync on the btrfs filesystem mounted at "fs".

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.17.35)

guestfs_btrfs_fsck¶

 int
 guestfs_btrfs_fsck (guestfs_h *g,
                     const char *device,
                     ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_BTRFS_FSCK_SUPERBLOCK, int64_t superblock,
 GUESTFS_BTRFS_FSCK_REPAIR, int repair,

Used to check a btrfs filesystem, "device" is the device file where the filesystem is stored.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.17.43)

guestfs_btrfs_fsck_va¶

 int
 guestfs_btrfs_fsck_va (guestfs_h *g,
                        const char *device,
                        va_list args);

This is the "va_list variant" of "guestfs_btrfs_fsck".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_btrfs_fsck_argv¶

 int
 guestfs_btrfs_fsck_argv (guestfs_h *g,
                          const char *device,
                          const struct guestfs_btrfs_fsck_argv *optargs);

This is the "argv variant" of "guestfs_btrfs_fsck".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_btrfs_image¶

 int
 guestfs_btrfs_image (guestfs_h *g,
                      char *const *source,
                      const char *image,
                      ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_BTRFS_IMAGE_COMPRESSLEVEL, int compresslevel,

This is used to create an image of a btrfs filesystem. All data will be zeroed, but metadata and the like is preserved.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.32)

guestfs_btrfs_image_va¶

 int
 guestfs_btrfs_image_va (guestfs_h *g,
                         char *const *source,
                         const char *image,
                         va_list args);

This is the "va_list variant" of "guestfs_btrfs_image".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_btrfs_image_argv¶

 int
 guestfs_btrfs_image_argv (guestfs_h *g,
                           char *const *source,
                           const char *image,
                           const struct guestfs_btrfs_image_argv *optargs);

This is the "argv variant" of "guestfs_btrfs_image".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_btrfs_qgroup_assign¶

 int
 guestfs_btrfs_qgroup_assign (guestfs_h *g,
                              const char *src,
                              const char *dst,
                              const char *path);

Add qgroup "src" to parent qgroup "dst". This command can group several qgroups into a parent qgroup to share common limit.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.17)

guestfs_btrfs_qgroup_create¶

 int
 guestfs_btrfs_qgroup_create (guestfs_h *g,
                              const char *qgroupid,
                              const char *subvolume);

Create a quota group (qgroup) for subvolume at "subvolume".

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.17)

guestfs_btrfs_qgroup_destroy¶

 int
 guestfs_btrfs_qgroup_destroy (guestfs_h *g,
                               const char *qgroupid,
                               const char *subvolume);

Destroy a quota group.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.17)

guestfs_btrfs_qgroup_limit¶

 int
 guestfs_btrfs_qgroup_limit (guestfs_h *g,
                             const char *subvolume,
                             int64_t size);

Limit the size of the subvolume with path "subvolume".

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.17)

guestfs_btrfs_qgroup_remove¶

 int
 guestfs_btrfs_qgroup_remove (guestfs_h *g,
                              const char *src,
                              const char *dst,
                              const char *path);

Remove qgroup "src" from the parent qgroup "dst".

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.17)

guestfs_btrfs_qgroup_show¶

 struct guestfs_btrfsqgroup_list *
 guestfs_btrfs_qgroup_show (guestfs_h *g,
                            const char *path);

Show all subvolume quota groups in a btrfs filesystem, including their usages.

This function returns a "struct guestfs_btrfsqgroup_list *", or NULL if there was an error. The caller must call "guestfs_free_btrfsqgroup_list" after use.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.17)

guestfs_btrfs_quota_enable¶

 int
 guestfs_btrfs_quota_enable (guestfs_h *g,
                             const char *fs,
                             int enable);

Enable or disable subvolume quota support for filesystem which contains "path".

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.17)

guestfs_btrfs_quota_rescan¶

 int
 guestfs_btrfs_quota_rescan (guestfs_h *g,
                             const char *fs);

Trash all qgroup numbers and scan the metadata again with the current config.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.17)

guestfs_btrfs_replace¶

 int
 guestfs_btrfs_replace (guestfs_h *g,
                        const char *srcdev,
                        const char *targetdev,
                        const char *mntpoint);

Replace device of a btrfs filesystem. On a live filesystem, duplicate the data to the target device which is currently stored on the source device. After completion of the operation, the source device is wiped out and removed from the filesystem.

The "targetdev" needs to be same size or larger than the "srcdev". Devices which are currently mounted are never allowed to be used as the "targetdev".

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.48)

guestfs_btrfs_rescue_chunk_recover¶

 int
 guestfs_btrfs_rescue_chunk_recover (guestfs_h *g,
                                     const char *device);

Recover the chunk tree of btrfs filesystem by scanning the devices one by one.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.22)

guestfs_btrfs_rescue_super_recover¶

 int
 guestfs_btrfs_rescue_super_recover (guestfs_h *g,
                                     const char *device);

Recover bad superblocks from good copies.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.22)

guestfs_btrfs_scrub_cancel¶

 int
 guestfs_btrfs_scrub_cancel (guestfs_h *g,
                             const char *path);

Cancel a running scrub on a btrfs filesystem.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.22)

guestfs_btrfs_scrub_resume¶

 int
 guestfs_btrfs_scrub_resume (guestfs_h *g,
                             const char *path);

Resume a previously canceled or interrupted scrub on a btrfs filesystem.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.22)

guestfs_btrfs_scrub_start¶

 int
 guestfs_btrfs_scrub_start (guestfs_h *g,
                            const char *path);

Reads all the data and metadata on the filesystem, and uses checksums and the duplicate copies from RAID storage to identify and repair any corrupt data.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.22)

guestfs_btrfs_scrub_status¶

 struct guestfs_btrfsscrub *
 guestfs_btrfs_scrub_status (guestfs_h *g,
                             const char *path);

Show status of running or finished scrub on a btrfs filesystem.

This function returns a "struct guestfs_btrfsscrub *", or NULL if there was an error. The caller must call "guestfs_free_btrfsscrub" after use.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.26)

guestfs_btrfs_set_seeding¶

 int
 guestfs_btrfs_set_seeding (guestfs_h *g,
                            const char *device,
                            int seeding);

Enable or disable the seeding feature of a device that contains a btrfs filesystem.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.17.43)

guestfs_btrfs_subvolume_create¶

 int
 guestfs_btrfs_subvolume_create (guestfs_h *g,
                                 const char *dest);

This function is provided for backwards compatibility with earlier versions of libguestfs. It simply calls "guestfs_btrfs_subvolume_create_opts" with no optional arguments.

(Added in 1.17.35)

guestfs_btrfs_subvolume_create_opts¶

 int
 guestfs_btrfs_subvolume_create_opts (guestfs_h *g,
                                      const char *dest,
                                      ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_BTRFS_SUBVOLUME_CREATE_OPTS_QGROUPID, const char *qgroupid,

Create a btrfs subvolume. The "dest" argument is the destination directory and the name of the subvolume, in the form /path/to/dest/name. The optional parameter "qgroupid" represents the qgroup which the newly created subvolume will be added to.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.17.35)

guestfs_btrfs_subvolume_create_opts_va¶

 int
 guestfs_btrfs_subvolume_create_opts_va (guestfs_h *g,
                                         const char *dest,
                                         va_list args);

This is the "va_list variant" of "guestfs_btrfs_subvolume_create_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_btrfs_subvolume_create_opts_argv¶

 int
 guestfs_btrfs_subvolume_create_opts_argv (guestfs_h *g,
                                           const char *dest,
                                           const struct guestfs_btrfs_subvolume_create_opts_argv *optargs);

This is the "argv variant" of "guestfs_btrfs_subvolume_create_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_btrfs_subvolume_delete¶

 int
 guestfs_btrfs_subvolume_delete (guestfs_h *g,
                                 const char *subvolume);

Delete the named btrfs subvolume or snapshot.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.17.35)

guestfs_btrfs_subvolume_get_default¶

 int64_t
 guestfs_btrfs_subvolume_get_default (guestfs_h *g,
                                      const char *fs);

Get the default subvolume or snapshot of a filesystem mounted at "mountpoint".

On error this function returns -1.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.17)

guestfs_btrfs_subvolume_list¶

 struct guestfs_btrfssubvolume_list *
 guestfs_btrfs_subvolume_list (guestfs_h *g,
                               const char *fs);

List the btrfs snapshots and subvolumes of the btrfs filesystem which is mounted at "fs".

This function returns a "struct guestfs_btrfssubvolume_list *", or NULL if there was an error. The caller must call "guestfs_free_btrfssubvolume_list" after use.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.17.35)

guestfs_btrfs_subvolume_set_default¶

 int
 guestfs_btrfs_subvolume_set_default (guestfs_h *g,
                                      int64_t id,
                                      const char *fs);

Set the subvolume of the btrfs filesystem "fs" which will be mounted by default. See "guestfs_btrfs_subvolume_list" to get a list of subvolumes.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.17.35)

guestfs_btrfs_subvolume_show¶

 char **
 guestfs_btrfs_subvolume_show (guestfs_h *g,
                               const char *subvolume);

Return detailed information of the subvolume.

This function returns a NULL-terminated array of strings, or NULL if there was an error. The array of strings will always have length "2n+1", where "n" keys and values alternate, followed by the trailing NULL entry. The caller must free the strings and the array after use.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.17)

guestfs_btrfs_subvolume_snapshot¶

 int
 guestfs_btrfs_subvolume_snapshot (guestfs_h *g,
                                   const char *source,
                                   const char *dest);

This function is provided for backwards compatibility with earlier versions of libguestfs. It simply calls "guestfs_btrfs_subvolume_snapshot_opts" with no optional arguments.

(Added in 1.17.35)

guestfs_btrfs_subvolume_snapshot_opts¶

 int
 guestfs_btrfs_subvolume_snapshot_opts (guestfs_h *g,
                                        const char *source,
                                        const char *dest,
                                        ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_BTRFS_SUBVOLUME_SNAPSHOT_OPTS_RO, int ro,
 GUESTFS_BTRFS_SUBVOLUME_SNAPSHOT_OPTS_QGROUPID, const char *qgroupid,

Create a 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. By default the newly created snapshot is writable, if the value of optional parameter "ro" is true, then a readonly snapshot is created. The optional parameter "qgroupid" represents the qgroup which the newly created snapshot will be added to.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.17.35)

guestfs_btrfs_subvolume_snapshot_opts_va¶

 int
 guestfs_btrfs_subvolume_snapshot_opts_va (guestfs_h *g,
                                           const char *source,
                                           const char *dest,
                                           va_list args);

This is the "va_list variant" of "guestfs_btrfs_subvolume_snapshot_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_btrfs_subvolume_snapshot_opts_argv¶

 int
 guestfs_btrfs_subvolume_snapshot_opts_argv (guestfs_h *g,
                                             const char *source,
                                             const char *dest,
                                             const struct guestfs_btrfs_subvolume_snapshot_opts_argv *optargs);

This is the "argv variant" of "guestfs_btrfs_subvolume_snapshot_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_btrfstune_enable_extended_inode_refs¶

 int
 guestfs_btrfstune_enable_extended_inode_refs (guestfs_h *g,
                                               const char *device);

This will Enable extended inode refs.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.29)

guestfs_btrfstune_enable_skinny_metadata_extent_refs¶

 int
 guestfs_btrfstune_enable_skinny_metadata_extent_refs (guestfs_h *g,
                                                       const char *device);

This enable skinny metadata extent refs.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.29)

guestfs_btrfstune_seeding¶

 int
 guestfs_btrfstune_seeding (guestfs_h *g,
                            const char *device,
                            int seeding);

Enable seeding of a btrfs device, this will force a fs readonly so that you can use it to build other filesystems.

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.29.29)

guestfs_c_pointer¶

 int64_t
 guestfs_c_pointer (guestfs_h *g);

In non-C language bindings, this allows you to retrieve the underlying C pointer to the handle (ie. "guestfs_h *"). The purpose of this is to allow other libraries to interwork with libguestfs.

On error this function returns -1.

(Added in 1.29.17)

guestfs_canonical_device_name¶

 char *
 guestfs_canonical_device_name (guestfs_h *g,
                                const char *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".

/dev/mapper/VG-LV

/dev/dm-N

Converted to /dev/VG/LV form using "guestfs_lvm_canonical_lv_name".

Other strings are returned unmodified.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.19.7)

guestfs_cap_get_file¶

 char *
 guestfs_cap_get_file (guestfs_h *g,
                       const char *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.

This function returns a string, or NULL on error. The caller must free the returned string after use.

This function depends on the feature "linuxcaps". See also "guestfs_feature_available".

(Added in 1.19.63)

guestfs_cap_set_file¶

 int
 guestfs_cap_set_file (guestfs_h *g,
                       const char *path,
                       const char *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)).

This function returns 0 on success or -1 on error.

This function depends on the feature "linuxcaps". See also "guestfs_feature_available".

(Added in 1.19.63)

guestfs_case_sensitive_path¶

 char *
 guestfs_case_sensitive_path (guestfs_h *g,
                              const char *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: https://www.tuxera.com/community/ntfs-3g-faq/#posixfilenames1

"guestfs_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:

"guestfs_case_sensitive_path" ("/windows/system32/netkvm.sys")

"Windows/System32/netkvm.sys"

"guestfs_case_sensitive_path" ("/windows/system32/NoSuchFile")

"Windows/System32/NoSuchFile"

"guestfs_case_sensitive_path" ("/windows/system33/netkvm.sys")

ERROR

Note: Because of the above behaviour, "guestfs_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 "guestfs_realpath".

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.0.75)

guestfs_cat¶

 char *
 guestfs_cat (guestfs_h *g,
              const char *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 "guestfs_read_file" or "guestfs_download" functions.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 0.4)

guestfs_checksum¶

 char *
 guestfs_checksum (guestfs_h *g,
                   const char *csumtype,
                   const char *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.

"gost"

"gost12"

Compute the checksum using GOST R34.11-94 or GOST R34.11-2012 message digest.

"md5"

Compute the MD5 hash (using the md5sum(1) program).

"sha1"

Compute the SHA1 hash (using the sha1sum(1) program).

"sha224"

Compute the SHA224 hash (using the sha224sum(1) program).

"sha256"

Compute the SHA256 hash (using the sha256sum(1) program).

"sha384"

Compute the SHA384 hash (using the sha384sum(1) program).

"sha512"

Compute the SHA512 hash (using the sha512sum(1) program).

The checksum is returned as a printable string.

To get the checksum for a device, use "guestfs_checksum_device".

To get the checksums for many files, use "guestfs_checksums_out".

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.0.2)

guestfs_checksum_device¶

 char *
 guestfs_checksum_device (guestfs_h *g,
                          const char *csumtype,
                          const char *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 "guestfs_checksum" command.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.3.2)

guestfs_checksums_out¶

 int
 guestfs_checksums_out (guestfs_h *g,
                        const char *csumtype,
                        const char *directory,
                        const char *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.

This function returns 0 on success or -1 on error.

(Added in 1.3.7)

guestfs_chmod¶

 int
 guestfs_chmod (guestfs_h *g,
                int mode,
                const char *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.

This function returns 0 on success or -1 on error.

(Added in 0.8)

guestfs_chown¶

 int
 guestfs_chown (guestfs_h *g,
                int owner,
                int group,
                const char *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).

This function returns 0 on success or -1 on error.

(Added in 0.8)

guestfs_clear_backend_setting¶

 int
 guestfs_clear_backend_setting (guestfs_h *g,
                                const char *name);

If there is a backend setting string matching "name" or beginning with "name=", then that string is removed from the backend settings.

This call returns the number of strings which were removed (which may be 0, 1 or greater than 1).

See "BACKEND", "BACKEND SETTINGS".

On error this function returns -1.

(Added in 1.27.2)

guestfs_clevis_luks_unlock¶

 int
 guestfs_clevis_luks_unlock (guestfs_h *g,
                             const char *device,
                             const char *mapname);

This command opens a block device that has been encrypted according to the Linux Unified Key Setup (LUKS) standard, using network-bound disk encryption (NBDE).

"device" is the encrypted block device.

The appliance will connect to the Tang servers noted in the tree of Clevis pins that is bound to a keyslot of the LUKS header. The Clevis pin tree may comprise "sss" (redudancy) pins as internal nodes (optionally), and "tang" pins as leaves. "tpm2" pins are not supported. The appliance unlocks the encrypted block device by combining responses from the Tang servers with metadata from the LUKS header; there is no "key" parameter.

This command will fail if networking has not been enabled for the appliance. Refer to "guestfs_set_network".

The command 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. Close the decrypted block device with "guestfs_cryptsetup_close".

"mapname" cannot be "control" because that name is reserved by device-mapper.

If this block device contains LVM volume groups, then calling "guestfs_lvm_scan" with the "activate" parameter "true" will make them visible.

Use "guestfs_list_dm_devices" to list all device mapper devices.

This function returns 0 on success or -1 on error.

This function depends on the feature "clevisluks". See also "guestfs_feature_available".

(Added in 1.49.3)

guestfs_command¶

 char *
 guestfs_command (guestfs_h *g,
                  char *const *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 "guestfs_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.

This function returns a string, or NULL on error. The caller must free the returned string after use.

Because of the message protocol, there is a transfer limit of somewhere between 2MB and 4MB. See "PROTOCOL LIMITS".

(Added in 1.9.1)

guestfs_command_lines¶

 char **
 guestfs_command_lines (guestfs_h *g,
                        char *const *arguments);

This is the same as "guestfs_command", but splits the result into a list of lines.

See also: "guestfs_sh_lines"

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

Because of the message protocol, there is a transfer limit of somewhere between 2MB and 4MB. See "PROTOCOL LIMITS".

(Added in 1.9.1)

guestfs_compress_device_out¶

 int
 guestfs_compress_device_out (guestfs_h *g,
                              const char *ctype,
                              const char *device,
                              const char *zdevice,
                              ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_COMPRESS_DEVICE_OUT_LEVEL, int 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 "guestfs_compress_out".

This function returns 0 on success or -1 on error.

(Added in 1.13.15)

guestfs_compress_device_out_va¶

 int
 guestfs_compress_device_out_va (guestfs_h *g,
                                 const char *ctype,
                                 const char *device,
                                 const char *zdevice,
                                 va_list args);

This is the "va_list variant" of "guestfs_compress_device_out".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_compress_device_out_argv¶

 int
 guestfs_compress_device_out_argv (guestfs_h *g,
                                   const char *ctype,
                                   const char *device,
                                   const char *zdevice,
                                   const struct guestfs_compress_device_out_argv *optargs);

This is the "argv variant" of "guestfs_compress_device_out".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_compress_out¶

 int
 guestfs_compress_out (guestfs_h *g,
                       const char *ctype,
                       const char *file,
                       const char *zfile,
                       ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_COMPRESS_OUT_LEVEL, int 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.

This function returns 0 on success or -1 on error.

(Added in 1.13.15)

guestfs_compress_out_va¶

 int
 guestfs_compress_out_va (guestfs_h *g,
                          const char *ctype,
                          const char *file,
                          const char *zfile,
                          va_list args);

This is the "va_list variant" of "guestfs_compress_out".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_compress_out_argv¶

 int
 guestfs_compress_out_argv (guestfs_h *g,
                            const char *ctype,
                            const char *file,
                            const char *zfile,
                            const struct guestfs_compress_out_argv *optargs);

This is the "argv variant" of "guestfs_compress_out".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_config¶

 int
 guestfs_config (guestfs_h *g,
                 const char *hvparam,
                 const char *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.

This function returns 0 on success or -1 on error.

(Added in 0.3)

guestfs_copy_attributes¶

 int
 guestfs_copy_attributes (guestfs_h *g,
                          const char *src,
                          const char *dest,
                          ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_COPY_ATTRIBUTES_ALL, int all,
 GUESTFS_COPY_ATTRIBUTES_MODE, int mode,
 GUESTFS_COPY_ATTRIBUTES_XATTRIBUTES, int xattributes,
 GUESTFS_COPY_ATTRIBUTES_OWNERSHIP, int ownership,

Copy the attributes of a path (which can be a file or a directory) to another path.

By default no attribute is copied, so make sure to specify any (or "all" to copy everything).

The optional arguments specify which attributes can be copied:

"mode"

Copy part of the file mode from "source" to "destination". Only the UNIX permissions and the sticky/setuid/setgid bits can be copied.

"xattributes"

Copy the Linux extended attributes (xattrs) from "source" to "destination". This flag does nothing if the linuxxattrs feature is not available (see "guestfs_feature_available").

"ownership"

Copy the owner uid and the group gid of "source" to "destination".

"all"

Copy all the attributes from "source" to "destination". Enabling it enables all the other flags, if they are not specified already.

This function returns 0 on success or -1 on error.

(Added in 1.25.21)

guestfs_copy_attributes_va¶

 int
 guestfs_copy_attributes_va (guestfs_h *g,
                             const char *src,
                             const char *dest,
                             va_list args);

This is the "va_list variant" of "guestfs_copy_attributes".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_copy_attributes_argv¶

 int
 guestfs_copy_attributes_argv (guestfs_h *g,
                               const char *src,
                               const char *dest,
                               const struct guestfs_copy_attributes_argv *optargs);

This is the "argv variant" of "guestfs_copy_attributes".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_copy_device_to_device¶

 int
 guestfs_copy_device_to_device (guestfs_h *g,
                                const char *src,
                                const char *dest,
                                ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_COPY_DEVICE_TO_DEVICE_SRCOFFSET, int64_t srcoffset,
 GUESTFS_COPY_DEVICE_TO_DEVICE_DESTOFFSET, int64_t destoffset,
 GUESTFS_COPY_DEVICE_TO_DEVICE_SIZE, int64_t size,
 GUESTFS_COPY_DEVICE_TO_DEVICE_SPARSE, int sparse,
 GUESTFS_COPY_DEVICE_TO_DEVICE_APPEND, int append,

The four calls "guestfs_copy_device_to_device", "guestfs_copy_device_to_file", "guestfs_copy_file_to_device", and "guestfs_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 destination is a file and the "append" flag is not set, then the destination file is truncated. If the "append" flag is set, then the copy appends to the destination file. The "append" flag currently cannot be set for devices.

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.

This function returns 0 on success or -1 on error.

This long-running command can generate progress notification messages so that the caller can display a progress bar or indicator. To receive these messages, the caller must register a progress event callback. See "GUESTFS_EVENT_PROGRESS".

(Added in 1.13.25)

guestfs_copy_device_to_device_va¶

 int
 guestfs_copy_device_to_device_va (guestfs_h *g,
                                   const char *src,
                                   const char *dest,
                                   va_list args);

This is the "va_list variant" of "guestfs_copy_device_to_device".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_copy_device_to_device_argv¶

 int
 guestfs_copy_device_to_device_argv (guestfs_h *g,
                                     const char *src,
                                     const char *dest,
                                     const struct guestfs_copy_device_to_device_argv *optargs);

This is the "argv variant" of "guestfs_copy_device_to_device".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_copy_device_to_file¶

 int
 guestfs_copy_device_to_file (guestfs_h *g,
                              const char *src,
                              const char *dest,
                              ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_COPY_DEVICE_TO_FILE_SRCOFFSET, int64_t srcoffset,
 GUESTFS_COPY_DEVICE_TO_FILE_DESTOFFSET, int64_t destoffset,
 GUESTFS_COPY_DEVICE_TO_FILE_SIZE, int64_t size,
 GUESTFS_COPY_DEVICE_TO_FILE_SPARSE, int sparse,
 GUESTFS_COPY_DEVICE_TO_FILE_APPEND, int append,

See "guestfs_copy_device_to_device" for a general overview of this call.

This function returns 0 on success or -1 on error.

This long-running command can generate progress notification messages so that the caller can display a progress bar or indicator. To receive these messages, the caller must register a progress event callback. See "GUESTFS_EVENT_PROGRESS".

(Added in 1.13.25)

guestfs_copy_device_to_file_va¶

 int
 guestfs_copy_device_to_file_va (guestfs_h *g,
                                 const char *src,
                                 const char *dest,
                                 va_list args);

This is the "va_list variant" of "guestfs_copy_device_to_file".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_copy_device_to_file_argv¶

 int
 guestfs_copy_device_to_file_argv (guestfs_h *g,
                                   const char *src,
                                   const char *dest,
                                   const struct guestfs_copy_device_to_file_argv *optargs);

This is the "argv variant" of "guestfs_copy_device_to_file".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_copy_file_to_device¶

 int
 guestfs_copy_file_to_device (guestfs_h *g,
                              const char *src,
                              const char *dest,
                              ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_COPY_FILE_TO_DEVICE_SRCOFFSET, int64_t srcoffset,
 GUESTFS_COPY_FILE_TO_DEVICE_DESTOFFSET, int64_t destoffset,
 GUESTFS_COPY_FILE_TO_DEVICE_SIZE, int64_t size,
 GUESTFS_COPY_FILE_TO_DEVICE_SPARSE, int sparse,
 GUESTFS_COPY_FILE_TO_DEVICE_APPEND, int append,

See "guestfs_copy_device_to_device" for a general overview of this call.

This function returns 0 on success or -1 on error.

This long-running command can generate progress notification messages so that the caller can display a progress bar or indicator. To receive these messages, the caller must register a progress event callback. See "GUESTFS_EVENT_PROGRESS".

(Added in 1.13.25)

guestfs_copy_file_to_device_va¶

 int
 guestfs_copy_file_to_device_va (guestfs_h *g,
                                 const char *src,
                                 const char *dest,
                                 va_list args);

This is the "va_list variant" of "guestfs_copy_file_to_device".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_copy_file_to_device_argv¶

 int
 guestfs_copy_file_to_device_argv (guestfs_h *g,
                                   const char *src,
                                   const char *dest,
                                   const struct guestfs_copy_file_to_device_argv *optargs);

This is the "argv variant" of "guestfs_copy_file_to_device".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_copy_file_to_file¶

 int
 guestfs_copy_file_to_file (guestfs_h *g,
                            const char *src,
                            const char *dest,
                            ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_COPY_FILE_TO_FILE_SRCOFFSET, int64_t srcoffset,
 GUESTFS_COPY_FILE_TO_FILE_DESTOFFSET, int64_t destoffset,
 GUESTFS_COPY_FILE_TO_FILE_SIZE, int64_t size,
 GUESTFS_COPY_FILE_TO_FILE_SPARSE, int sparse,
 GUESTFS_COPY_FILE_TO_FILE_APPEND, int append,

See "guestfs_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 "guestfs_cp", "guestfs_cp_a" and "guestfs_mv" for general file copying and moving functions.

This function returns 0 on success or -1 on error.

This long-running command can generate progress notification messages so that the caller can display a progress bar or indicator. To receive these messages, the caller must register a progress event callback. See "GUESTFS_EVENT_PROGRESS".

(Added in 1.13.25)

guestfs_copy_file_to_file_va¶

 int
 guestfs_copy_file_to_file_va (guestfs_h *g,
                               const char *src,
                               const char *dest,
                               va_list args);

This is the "va_list variant" of "guestfs_copy_file_to_file".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_copy_file_to_file_argv¶

 int
 guestfs_copy_file_to_file_argv (guestfs_h *g,
                                 const char *src,
                                 const char *dest,
                                 const struct guestfs_copy_file_to_file_argv *optargs);

This is the "argv variant" of "guestfs_copy_file_to_file".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_copy_in¶

 int
 guestfs_copy_in (guestfs_h *g,
                  const char *localpath,
                  const char *remotedir);

"guestfs_copy_in" copies local files or directories recursively into the disk image, placing them in the directory called "remotedir" (which must exist).

Wildcards cannot be used.

This function returns 0 on success or -1 on error.

(Added in 1.29.24)

guestfs_copy_out¶

 int
 guestfs_copy_out (guestfs_h *g,
                   const char *remotepath,
                   const char *localdir);

"guestfs_copy_out" copies remote files or directories recursively out of the disk image, placing them on the host disk in a local directory called "localdir" (which must exist).

To download to the current directory, use "." as in:

 C<guestfs_copy_out> /home .

Wildcards cannot be used.

This function returns 0 on success or -1 on error.

(Added in 1.29.24)

guestfs_copy_size¶

 int
 guestfs_copy_size (guestfs_h *g,
                    const char *src,
                    const char *dest,
                    int64_t size);

This function is deprecated. In new code, use the "guestfs_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.

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 returns 0 on success or -1 on error.

This long-running command can generate progress notification messages so that the caller can display a progress bar or indicator. To receive these messages, the caller must register a progress event callback. See "GUESTFS_EVENT_PROGRESS".

(Added in 1.0.87)

guestfs_cp¶

 int
 guestfs_cp (guestfs_h *g,
             const char *src,
             const char *dest);

This copies a file from "src" to "dest" where "dest" is either a destination filename or destination directory.

This function returns 0 on success or -1 on error.

(Added in 1.0.18)

guestfs_cp_a¶

 int
 guestfs_cp_a (guestfs_h *g,
               const char *src,
               const char *dest);

This copies a file or directory from "src" to "dest" recursively using the "cp -a" command.

This function returns 0 on success or -1 on error.

(Added in 1.0.18)

guestfs_cp_r¶

 int
 guestfs_cp_r (guestfs_h *g,
               const char *src,
               const char *dest);

This copies a file or directory from "src" to "dest" recursively using the "cp -rP" command.

Most users should use "guestfs_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).

This function returns 0 on success or -1 on error.

(Added in 1.21.38)

guestfs_cpio_out¶

 int
 guestfs_cpio_out (guestfs_h *g,
                   const char *directory,
                   const char *cpiofile,
                   ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_CPIO_OUT_FORMAT, const char *format,

This command packs the contents of directory and downloads it to local file "cpiofile".

The optional "format" parameter can be used to select the format. Only the following formats are currently permitted:

"newc"

New (SVR4) portable format. This format happens to be compatible with the cpio-like format used by the Linux kernel for initramfs.

This is the default format.

"crc"

New (SVR4) portable format with a checksum.

This function returns 0 on success or -1 on error.

(Added in 1.27.9)

guestfs_cpio_out_va¶

 int
 guestfs_cpio_out_va (guestfs_h *g,
                      const char *directory,
                      const char *cpiofile,
                      va_list args);

This is the "va_list variant" of "guestfs_cpio_out".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_cpio_out_argv¶

 int
 guestfs_cpio_out_argv (guestfs_h *g,
                        const char *directory,
                        const char *cpiofile,
                        const struct guestfs_cpio_out_argv *optargs);

This is the "argv variant" of "guestfs_cpio_out".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_cryptsetup_close¶

 int
 guestfs_cryptsetup_close (guestfs_h *g,
                           const char *device);

This closes an encrypted device that was created earlier by "guestfs_cryptsetup_open". The "device" parameter must be the name of the mapping device (ie. /dev/mapper/mapname) and not the name of the underlying block device.

This function returns 0 on success or -1 on error.

This function depends on the feature "luks". See also "guestfs_feature_available".

(Added in 1.43.2)

guestfs_cryptsetup_open¶

 int
 guestfs_cryptsetup_open (guestfs_h *g,
                          const char *device,
                          const char *key,
                          const char *mapname,
                          ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_CRYPTSETUP_OPEN_READONLY, int readonly,
 GUESTFS_CRYPTSETUP_OPEN_CRYPTTYPE, const char *crypttype,
 GUESTFS_CRYPTSETUP_OPEN_CIPHER, const char *cipher,

This command opens a block device which has been encrypted according to the Linux Unified Key Setup (LUKS) standard, Windows BitLocker, or some other types.

"device" is the encrypted block device or partition.

The caller must supply one of the keys associated with the encrypted 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.

"mapname" cannot be "control" because that name is reserved by device-mapper.

If the optional "crypttype" parameter is not present then libguestfs tries to guess the correct type (for example LUKS or BitLocker). However you can override this by specifying one of the following types:

"luks"

A Linux LUKS device.

"bitlk"

A Windows BitLocker device.

The optional "readonly" flag, if set to true, creates a read-only mapping.

The optional "cipher" parameter allows specifying which cipher to use.

If this block device contains LVM volume groups, then calling "guestfs_lvm_scan" with the "activate" parameter "true" will make them visible.

Use "guestfs_list_dm_devices" to list all device mapper devices.

This function returns 0 on success or -1 on error.

This function takes a key or passphrase parameter which could contain sensitive material. Read the section "KEYS AND PASSPHRASES" for more information.

This function depends on the feature "luks". See also "guestfs_feature_available".

(Added in 1.43.2)

guestfs_cryptsetup_open_va¶

 int
 guestfs_cryptsetup_open_va (guestfs_h *g,
                             const char *device,
                             const char *key,
                             const char *mapname,
                             va_list args);

This is the "va_list variant" of "guestfs_cryptsetup_open".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_cryptsetup_open_argv¶

 int
 guestfs_cryptsetup_open_argv (guestfs_h *g,
                               const char *device,
                               const char *key,
                               const char *mapname,
                               const struct guestfs_cryptsetup_open_argv *optargs);

This is the "argv variant" of "guestfs_cryptsetup_open".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_dd¶

 int
 guestfs_dd (guestfs_h *g,
             const char *src,
             const char *dest);

This function is deprecated. In new code, use the "guestfs_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.

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 "guestfs_copy_device_to_device").

This function returns 0 on success or -1 on error.

(Added in 1.0.80)

guestfs_device_index¶

 int
 guestfs_device_index (guestfs_h *g,
                       const char *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 "guestfs_list_devices".

See also "guestfs_list_devices", "guestfs_part_to_dev", "guestfs_device_name".

On error this function returns -1.

(Added in 1.19.7)

guestfs_device_name¶

 char *
 guestfs_device_name (guestfs_h *g,
                      int index);

This function takes a device index and returns the device name. For example index 0 will return the string "/dev/sda".

The drive index must have been added to the handle.

See also "guestfs_list_devices", "guestfs_part_to_dev", "guestfs_device_index".

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.49.1)

guestfs_df¶

 char *
 guestfs_df (guestfs_h *g);

This command runs the df(1) 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 "guestfs_statvfs" from programs.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.0.54)

guestfs_df_h¶

 char *
 guestfs_df_h (guestfs_h *g);

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 "guestfs_statvfs" from programs.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.0.54)

guestfs_disk_create¶

 int
 guestfs_disk_create (guestfs_h *g,
                      const char *filename,
                      const char *format,
                      int64_t size,
                      ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_DISK_CREATE_BACKINGFILE, const char *backingfile,
 GUESTFS_DISK_CREATE_BACKINGFORMAT, const char *backingformat,
 GUESTFS_DISK_CREATE_PREALLOCATION, const char *preallocation,
 GUESTFS_DISK_CREATE_COMPAT, const char *compat,
 GUESTFS_DISK_CREATE_CLUSTERSIZE, int clustersize,

Create a blank disk image called filename (a host file) with format "format" (usually "raw" or "qcow2"). The size is "size" bytes.

If used with the optional "backingfile" parameter, then a snapshot is created on top of the backing file. In this case, "size" must be passed as -1. The size of the snapshot is the same as the size of the backing file, which is discovered automatically. You are encouraged to also pass "backingformat" to describe the format of "backingfile".

If filename refers to a block device, then the device is formatted. The "size" is ignored since block devices have an intrinsic size.

The other optional parameters are:

"preallocation"

If format is "raw", then this can be either "off" (or "sparse") or "full" to create a sparse or fully allocated file respectively. The default is "off".

If format is "qcow2", then this can be "off" (or "sparse"), "metadata" or "full". Preallocating metadata can be faster when doing lots of writes, but uses more space. The default is "off".

"compat"

"qcow2" only: Pass the string 1.1 to use the advanced qcow2 format supported by qemu ≥ 1.1.

"clustersize"

"qcow2" only: Change the qcow2 cluster size. The default is 65536 (bytes) and this setting may be any power of two between 512 and 2097152.

Note that this call does not add the new disk to the handle. You may need to call "guestfs_add_drive_opts" separately.

This function returns 0 on success or -1 on error.

(Added in 1.25.31)

guestfs_disk_create_va¶

 int
 guestfs_disk_create_va (guestfs_h *g,
                         const char *filename,
                         const char *format,
                         int64_t size,
                         va_list args);

This is the "va_list variant" of "guestfs_disk_create".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_disk_create_argv¶

 int
 guestfs_disk_create_argv (guestfs_h *g,
                           const char *filename,
                           const char *format,
                           int64_t size,
                           const struct guestfs_disk_create_argv *optargs);

This is the "argv variant" of "guestfs_disk_create".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_disk_format¶

 char *
 guestfs_disk_format (guestfs_h *g,
                      const char *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".

See also: "DISK IMAGE FORMATS"

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.19.38)

guestfs_disk_has_backing_file¶

 int
 guestfs_disk_has_backing_file (guestfs_h *g,
                                const char *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".

This function returns a C truth value on success or -1 on error.

(Added in 1.19.39)

guestfs_disk_virtual_size¶

 int64_t
 guestfs_disk_virtual_size (guestfs_h *g,
                            const char *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".

On error this function returns -1.

(Added in 1.19.39)

guestfs_dmesg¶

 char *
 guestfs_dmesg (guestfs_h *g);

This returns the kernel messages (dmesg(1) 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 "guestfs_set_verbose" or by setting the environment variable "LIBGUESTFS_DEBUG=1" before running the program.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.0.18)

guestfs_download¶

 int
 guestfs_download (guestfs_h *g,
                   const char *remotefilename,
                   const char *filename);

Download file remotefilename and save it as filename on the local machine.

filename can also be a named pipe.

See also "guestfs_upload", "guestfs_cat".

This function returns 0 on success or -1 on error.

This long-running command can generate progress notification messages so that the caller can display a progress bar or indicator. To receive these messages, the caller must register a progress event callback. See "GUESTFS_EVENT_PROGRESS".

(Added in 1.0.2)

guestfs_download_blocks¶

 int
 guestfs_download_blocks (guestfs_h *g,
                          const char *device,
                          int64_t start,
                          int64_t stop,
                          const char *filename,
                          ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_DOWNLOAD_BLOCKS_UNALLOCATED, int unallocated,

Download the data units from start address to stop from the disk partition (eg. /dev/sda1) and save them as filename on the local machine.

The use of this API on sparse disk image formats such as QCOW, may result in large zero-filled files downloaded on the host.

The size of a data unit varies across filesystem implementations. On NTFS filesystems data units are referred as clusters while on ExtX ones they are referred as fragments.

If the optional "unallocated" flag is true (default is false), only the unallocated blocks will be extracted. This is useful to detect hidden data or to retrieve deleted files which data units have not been overwritten yet.

This function returns 0 on success or -1 on error.

This long-running command can generate progress notification messages so that the caller can display a progress bar or indicator. To receive these messages, the caller must register a progress event callback. See "GUESTFS_EVENT_PROGRESS".

This function depends on the feature "sleuthkit". See also "guestfs_feature_available".

(Added in 1.33.45)

guestfs_download_blocks_va¶

 int
 guestfs_download_blocks_va (guestfs_h *g,
                             const char *device,
                             int64_t start,
                             int64_t stop,
                             const char *filename,
                             va_list args);

This is the "va_list variant" of "guestfs_download_blocks".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_download_blocks_argv¶

 int
 guestfs_download_blocks_argv (guestfs_h *g,
                               const char *device,
                               int64_t start,
                               int64_t stop,
                               const char *filename,
                               const struct guestfs_download_blocks_argv *optargs);

This is the "argv variant" of "guestfs_download_blocks".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_download_inode¶

 int
 guestfs_download_inode (guestfs_h *g,
                         const char *device,
                         int64_t inode,
                         const char *filename);

Download a file given its inode from the disk partition (eg. /dev/sda1) and save it as filename on the local machine.

It is not required to mount the disk to run this command.

The command is capable of downloading deleted or inaccessible files.

This function returns 0 on success or -1 on error.

This long-running command can generate progress notification messages so that the caller can display a progress bar or indicator. To receive these messages, the caller must register a progress event callback. See "GUESTFS_EVENT_PROGRESS".

This function depends on the feature "sleuthkit". See also "guestfs_feature_available".

(Added in 1.33.14)

guestfs_download_offset¶

 int
 guestfs_download_offset (guestfs_h *g,
                          const char *remotefilename,
                          const char *filename,
                          int64_t offset,
                          int64_t 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 "guestfs_pread", and this call always reads the full amount unless an error occurs.

See also "guestfs_download", "guestfs_pread".

This function returns 0 on success or -1 on error.

This long-running command can generate progress notification messages so that the caller can display a progress bar or indicator. To receive these messages, the caller must register a progress event callback. See "GUESTFS_EVENT_PROGRESS".

(Added in 1.5.17)

guestfs_drop_caches¶

 int
 guestfs_drop_caches (guestfs_h *g,
                      int 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 https://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.

This function returns 0 on success or -1 on error.

(Added in 1.0.18)

guestfs_du¶

 int64_t
 guestfs_du (guestfs_h *g,
             const char *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).

On error this function returns -1.

This long-running command can generate progress notification messages so that the caller can display a progress bar or indicator. To receive these messages, the caller must register a progress event callback. See "GUESTFS_EVENT_PROGRESS".

(Added in 1.0.54)

guestfs_e2fsck¶

 int
 guestfs_e2fsck (guestfs_h *g,
                 const char *device,
                 ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_E2FSCK_CORRECT, int correct,
 GUESTFS_E2FSCK_FORCEALL, int 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.

This function returns 0 on success or -1 on error.

(Added in 1.15.17)

guestfs_e2fsck_va¶

 int
 guestfs_e2fsck_va (guestfs_h *g,
                    const char *device,
                    va_list args);

This is the "va_list variant" of "guestfs_e2fsck".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_e2fsck_argv¶

 int
 guestfs_e2fsck_argv (guestfs_h *g,
                      const char *device,
                      const struct guestfs_e2fsck_argv *optargs);

This is the "argv variant" of "guestfs_e2fsck".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_e2fsck_f¶

 int
 guestfs_e2fsck_f (guestfs_h *g,
                   const char *device);

This function is deprecated. In new code, use the "guestfs_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.

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 returns 0 on success or -1 on error.

(Added in 1.0.29)

guestfs_echo_daemon¶

 char *
 guestfs_echo_daemon (guestfs_h *g,
                      char *const *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 "guestfs_ping_daemon".

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.0.69)

guestfs_egrep¶

 char **
 guestfs_egrep (guestfs_h *g,
                const char *regex,
                const char *path);

This function is deprecated. In new code, use the "guestfs_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.

This calls the external egrep(1) program and returns the matching lines.

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

Because of the message protocol, there is a transfer limit of somewhere between 2MB and 4MB. See "PROTOCOL LIMITS".

(Added in 1.0.66)

guestfs_egrepi¶

 char **
 guestfs_egrepi (guestfs_h *g,
                 const char *regex,
                 const char *path);

This function is deprecated. In new code, use the "guestfs_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.

This calls the external "egrep -i" program and returns the matching lines.

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

Because of the message protocol, there is a transfer limit of somewhere between 2MB and 4MB. See "PROTOCOL LIMITS".

(Added in 1.0.66)

guestfs_equal¶

 int
 guestfs_equal (guestfs_h *g,
                const char *file1,
                const char *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.

This function returns a C truth value on success or -1 on error.

(Added in 1.0.18)

guestfs_exists¶

 int
 guestfs_exists (guestfs_h *g,
                 const char *path);

This returns "true" if and only if there is a file, directory (or anything) with the given "path" name.

See also "guestfs_is_file", "guestfs_is_dir", "guestfs_stat".

This function returns a C truth value on success or -1 on error.

(Added in 0.8)

guestfs_extlinux¶

 int
 guestfs_extlinux (guestfs_h *g,
                   const char *directory);

Install the SYSLINUX bootloader on the device mounted at directory. Unlike "guestfs_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" ("guestfs_part_set_bootable") and a Master Boot Record must be installed (eg. using "guestfs_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 "guestfs_syslinux".

This function returns 0 on success or -1 on error.

This function depends on the feature "extlinux". See also "guestfs_feature_available".

(Added in 1.21.27)

guestfs_f2fs_expand¶

 int
 guestfs_f2fs_expand (guestfs_h *g,
                      const char *device);

This expands a f2fs filesystem to match the size of the underlying device.

This function returns 0 on success or -1 on error.

This function depends on the feature "f2fs". See also "guestfs_feature_available".

(Added in 1.39.3)

guestfs_fallocate¶

 int
 guestfs_fallocate (guestfs_h *g,
                    const char *path,
                    int len);

This function is deprecated. In new code, use the "guestfs_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.

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 returns 0 on success or -1 on error.

(Added in 1.0.66)

guestfs_fallocate64¶

 int
 guestfs_fallocate64 (guestfs_h *g,
                      const char *path,
                      int64_t 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 "guestfs_truncate_size" instead.

The deprecated call "guestfs_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.

This function returns 0 on success or -1 on error.

(Added in 1.3.17)

guestfs_feature_available¶

 int
 guestfs_feature_available (guestfs_h *g,
                            char *const *groups);

This is the same as "guestfs_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 "guestfs_available".

This function returns a C truth value on success or -1 on error.

(Added in 1.21.26)

guestfs_fgrep¶

 char **
 guestfs_fgrep (guestfs_h *g,
                const char *pattern,
                const char *path);

This function is deprecated. In new code, use the "guestfs_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.

This calls the external fgrep(1) program and returns the matching lines.

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

Because of the message protocol, there is a transfer limit of somewhere between 2MB and 4MB. See "PROTOCOL LIMITS".

(Added in 1.0.66)

guestfs_fgrepi¶

 char **
 guestfs_fgrepi (guestfs_h *g,
                 const char *pattern,
                 const char *path);

This function is deprecated. In new code, use the "guestfs_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.

This calls the external "fgrep -i" program and returns the matching lines.

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

Because of the message protocol, there is a transfer limit of somewhere between 2MB and 4MB. See "PROTOCOL LIMITS".

(Added in 1.0.66)

guestfs_file¶

 char *
 guestfs_file (guestfs_h *g,
               const char *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 filename is not prepended to the output (like the file command -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), "guestfs_vfs_type", "guestfs_lstat", "guestfs_is_file", "guestfs_is_blockdev" (etc), "guestfs_is_zero".

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.9.1)

guestfs_file_architecture¶

 char *
 guestfs_file_architecture (guestfs_h *g,
                            const char *filename);

This detects the architecture of the binary filename, and returns it if known.

Currently defined architectures are:

"aarch64"

64 bit ARM.

"arm"

32 bit ARM.

"i386"

This string is returned for all 32 bit i386, i486, i586, i686 binaries irrespective of the precise processor requirements of the binary.

"ia64"

Intel Itanium.

"ppc"

32 bit Power PC.

"ppc64"

64 bit Power PC (big endian).

"ppc64le"

64 bit Power PC (little endian).

"loongarch64"

64 bit LoongArch64 (little endian).

"riscv32"

"riscv64"

"riscv128"

RISC-V 32-, 64- or 128-bit variants.

"s390"

31 bit IBM S/390.

"s390x"

64 bit IBM S/390.

"sparc"

32 bit SPARC.

"sparc64"

64 bit SPARC V9 and above.

"x86_64"

64 bit x86-64.

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.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.5.3)

guestfs_filesize¶

 int64_t
 guestfs_filesize (guestfs_h *g,
                   const char *file);

This command returns the size of file in bytes.

To get other stats about a file, use "guestfs_stat", "guestfs_lstat", "guestfs_is_dir", "guestfs_is_file" etc. To get the size of block devices, use "guestfs_blockdev_getsize64".

On error this function returns -1.

(Added in 1.0.82)

guestfs_filesystem_available¶

 int
 guestfs_filesystem_available (guestfs_h *g,
                               const char *filesystem);

Check whether libguestfs supports the named filesystem. The argument "filesystem" is a filesystem name, such as "ext3".

You must call "guestfs_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 "guestfs_available", "guestfs_feature_available", "AVAILABILITY".

This function returns a C truth value on success or -1 on error.

(Added in 1.19.5)

guestfs_filesystem_walk¶

 struct guestfs_tsk_dirent_list *
 guestfs_filesystem_walk (guestfs_h *g,
                          const char *device);

Walk through the internal structures of a disk partition (eg. /dev/sda1) in order to return a list of all the files and directories stored within.

It is not necessary to mount the disk partition to run this command.

All entries in the filesystem are returned. This function can list deleted or unaccessible files. The entries are not sorted.

The "tsk_dirent" structure contains the following fields.

"tsk_inode"

Filesystem reference number of the node. It might be 0 if the node has been deleted.

"tsk_type"

Basic file type information. See below for a detailed list of values.

"tsk_size"

File size in bytes. It might be -1 if the node has been deleted.

"tsk_name"

The file path relative to its directory.

"tsk_flags"

Bitfield containing extra information regarding the entry. It contains the logical OR of the following values:

"tsk_atime_sec"

"tsk_atime_nsec"

"tsk_mtime_sec"

"tsk_mtime_nsec"

"tsk_ctime_sec"

"tsk_ctime_nsec"

"tsk_crtime_sec"

"tsk_crtime_nsec"

Respectively, access, modification, last status change and creation time in Unix format in seconds and nanoseconds.

"tsk_nlink"

Number of file names pointing to this entry.

"tsk_link"

If the entry is a symbolic link, this field will contain the path to the target file.

The "tsk_type" 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

'h'

Shadow inode (Solaris)

'w'

Whiteout inode (BSD)

'u'

Unknown file type

This function returns a "struct guestfs_tsk_dirent_list *", or NULL if there was an error. The caller must call "guestfs_free_tsk_dirent_list" after use.

This long-running command can generate progress notification messages so that the caller can display a progress bar or indicator. To receive these messages, the caller must register a progress event callback. See "GUESTFS_EVENT_PROGRESS".

This function depends on the feature "libtsk". See also "guestfs_feature_available".

(Added in 1.33.39)

guestfs_fill¶

 int
 guestfs_fill (guestfs_h *g,
               int c,
               int len,
               const char *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 "guestfs_truncate_size". To create a file with a pattern of repeating bytes use "guestfs_fill_pattern".

This function returns 0 on success or -1 on error.

This long-running command can generate progress notification messages so that the caller can display a progress bar or indicator. To receive these messages, the caller must register a progress event callback. See "GUESTFS_EVENT_PROGRESS".

(Added in 1.0.79)

guestfs_fill_dir¶

 int
 guestfs_fill_dir (guestfs_h *g,
                   const char *dir,
                   int 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).

This function returns 0 on success or -1 on error.

(Added in 1.19.32)

guestfs_fill_pattern¶

 int
 guestfs_fill_pattern (guestfs_h *g,
                       const char *pattern,
                       int len,
                       const char *path);

This function is like "guestfs_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.

This function returns 0 on success or -1 on error.

This long-running command can generate progress notification messages so that the caller can display a progress bar or indicator. To receive these messages, the caller must register a progress event callback. See "GUESTFS_EVENT_PROGRESS".

(Added in 1.3.12)

guestfs_find¶

 char **
 guestfs_find (guestfs_h *g,
               const char *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 "guestfs_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.

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

(Added in 1.0.27)

guestfs_find0¶

 int
 guestfs_find0 (guestfs_h *g,
                const char *directory,
                const char *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 "guestfs_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.

This function returns 0 on success or -1 on error.

(Added in 1.0.74)

guestfs_find_inode¶

 struct guestfs_tsk_dirent_list *
 guestfs_find_inode (guestfs_h *g,
                     const char *device,
                     int64_t inode);

Searches all the entries associated with the given inode.

For each entry, a "tsk_dirent" structure is returned. See "filesystem_walk" for more information about "tsk_dirent" structures.

This function returns a "struct guestfs_tsk_dirent_list *", or NULL if there was an error. The caller must call "guestfs_free_tsk_dirent_list" after use.

This long-running command can generate progress notification messages so that the caller can display a progress bar or indicator. To receive these messages, the caller must register a progress event callback. See "GUESTFS_EVENT_PROGRESS".

This function depends on the feature "libtsk". See also "guestfs_feature_available".

(Added in 1.35.6)

guestfs_findfs_label¶

 char *
 guestfs_findfs_label (guestfs_h *g,
                       const char *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 "guestfs_vfs_label".

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.5.3)

guestfs_findfs_partlabel¶

 char *
 guestfs_findfs_partlabel (guestfs_h *g,
                           const char *label);

This command searches the partitions and returns the one which has the given label. An error is returned if no such partition can be found.

To find the label of a partition, use "guestfs_blkid" ("PART_ENTRY_NAME").

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.53.5)

guestfs_findfs_partuuid¶

 char *
 guestfs_findfs_partuuid (guestfs_h *g,
                          const char *uuid);

This command searches the partitions and returns the one which has the given partition UUID. An error is returned if no such partition can be found.

To find the UUID of a partition, use "guestfs_blkid" ("PART_ENTRY_UUID").

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.53.5)

guestfs_findfs_uuid¶

 char *
 guestfs_findfs_uuid (guestfs_h *g,
                      const char *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 "guestfs_vfs_uuid".

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.5.3)

guestfs_fsck¶

 int
 guestfs_fsck (guestfs_h *g,
               const char *fstype,
               const char *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".

On error this function returns -1.

(Added in 1.0.16)

guestfs_fstrim¶

 int
 guestfs_fstrim (guestfs_h *g,
                 const char *mountpoint,
                 ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_FSTRIM_OFFSET, int64_t offset,
 GUESTFS_FSTRIM_LENGTH, int64_t length,
 GUESTFS_FSTRIM_MINIMUMFREEEXTENT, int64_t 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.

In the case where the kernel vfs driver does not support trimming, this call will fail with errno set to "ENOTSUP". Currently this happens when trying to trim FAT filesystems.

See also "guestfs_zero_free_space". That is a slightly different operation that turns free space in the filesystem into zeroes. It is valid to call "guestfs_fstrim" either instead of, or after calling "guestfs_zero_free_space".

This function returns 0 on success or -1 on error.

This function depends on the feature "fstrim". See also "guestfs_feature_available".

(Added in 1.19.6)

guestfs_fstrim_va¶

 int
 guestfs_fstrim_va (guestfs_h *g,
                    const char *mountpoint,
                    va_list args);

This is the "va_list variant" of "guestfs_fstrim".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_fstrim_argv¶

 int
 guestfs_fstrim_argv (guestfs_h *g,
                      const char *mountpoint,
                      const struct guestfs_fstrim_argv *optargs);

This is the "argv variant" of "guestfs_fstrim".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_get_append¶

 const char *
 guestfs_get_append (guestfs_h *g);

Return the additional kernel options which are added to the libguestfs appliance kernel command line.

If "NULL" then no options are added.

This function returns a string which may be NULL. There is no way to return an error from this function. The string is owned by the guest handle and must not be freed.

(Added in 1.0.26)

guestfs_get_attach_method¶

 char *
 guestfs_get_attach_method (guestfs_h *g);

This function is deprecated. In new code, use the "guestfs_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.

Return the current backend.

See "guestfs_set_backend" and "BACKEND".

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.9.8)

guestfs_get_autosync¶

 int
 guestfs_get_autosync (guestfs_h *g);

Get the autosync flag.

This function returns a C truth value on success or -1 on error.

(Added in 0.3)

guestfs_get_backend¶

 char *
 guestfs_get_backend (guestfs_h *g);

Return the current backend.

This handle property was previously called the "attach method".

See "guestfs_set_backend" and "BACKEND".

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.21.26)

guestfs_get_backend_setting¶

 char *
 guestfs_get_backend_setting (guestfs_h *g,
                              const char *name);

Find a backend setting string which is either "name" or begins with "name=". If "name", this returns the string "1". If "name=", this returns the part after the equals sign (which may be an empty string).

If no such setting is found, this function throws an error. The errno (see "guestfs_last_errno") will be "ESRCH" in this case.

See "BACKEND", "BACKEND SETTINGS".

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.27.2)

guestfs_get_backend_settings¶

 char **
 guestfs_get_backend_settings (guestfs_h *g);

Return the current backend settings.

This call returns all backend settings strings. If you want to find a single backend setting, see "guestfs_get_backend_setting".

See "BACKEND", "BACKEND SETTINGS".

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

(Added in 1.25.24)

guestfs_get_cachedir¶

 char *
 guestfs_get_cachedir (guestfs_h *g);

Get the directory used by the handle to store the appliance cache.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.19.58)

guestfs_get_direct¶

 int
 guestfs_get_direct (guestfs_h *g);

This function is deprecated. In new code, use the "guestfs_internal_get_console_socket" 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.

Return the direct appliance mode flag.

This function returns a C truth value on success or -1 on error.

(Added in 1.0.72)

guestfs_get_e2attrs¶

 char *
 guestfs_get_e2attrs (guestfs_h *g,
                      const char *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 "guestfs_set_e2attrs".

Don't confuse these attributes with extended attributes (see "guestfs_getxattr").

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.17.31)

guestfs_get_e2generation¶

 int64_t
 guestfs_get_e2generation (guestfs_h *g,
                           const char *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 "guestfs_set_e2generation".

On error this function returns -1.

(Added in 1.17.31)

guestfs_get_e2label¶

 char *
 guestfs_get_e2label (guestfs_h *g,
                      const char *device);

This function is deprecated. In new code, use the "guestfs_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.

This returns the ext2/3/4 filesystem label of the filesystem on "device".

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.0.15)

guestfs_get_e2uuid¶

 char *
 guestfs_get_e2uuid (guestfs_h *g,
                     const char *device);

This function is deprecated. In new code, use the "guestfs_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.

This returns the ext2/3/4 filesystem UUID of the filesystem on "device".

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.0.15)

guestfs_get_hv¶

 char *
 guestfs_get_hv (guestfs_h *g);

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.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.23.17)

guestfs_get_identifier¶

 const char *
 guestfs_get_identifier (guestfs_h *g);

Get the handle identifier. See "guestfs_set_identifier".

This function returns a string, or NULL on error. The string is owned by the guest handle and must not be freed.

(Added in 1.31.14)

guestfs_get_libvirt_requested_credential_challenge¶

 char *
 guestfs_get_libvirt_requested_credential_challenge (guestfs_h *g,
                                                     int 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" for documentation and example code.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.19.52)

guestfs_get_libvirt_requested_credential_defresult¶

 char *
 guestfs_get_libvirt_requested_credential_defresult (guestfs_h *g,
                                                     int 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" for documentation and example code.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.19.52)

guestfs_get_libvirt_requested_credential_prompt¶

 char *
 guestfs_get_libvirt_requested_credential_prompt (guestfs_h *g,
                                                  int 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" for documentation and example code.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.19.52)

guestfs_get_libvirt_requested_credentials¶

 char **
 guestfs_get_libvirt_requested_credentials (guestfs_h *g);

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 "guestfs_set_libvirt_supported_credentials".

See "LIBVIRT AUTHENTICATION" for documentation and example code.

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

(Added in 1.19.52)

guestfs_get_memsize¶

 int
 guestfs_get_memsize (guestfs_h *g);

This gets the memory size in megabytes allocated to the hypervisor.

If "guestfs_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).

On error this function returns -1.

(Added in 1.0.55)

guestfs_get_network¶

 int
 guestfs_get_network (guestfs_h *g);

This returns the enable network flag.

This function returns a C truth value on success or -1 on error.

(Added in 1.5.4)

guestfs_get_path¶

 const char *
 guestfs_get_path (guestfs_h *g);

Return the current search path.

This is always non-NULL. If it wasn't set already, then this will return the default path.

This function returns a string, or NULL on error. The string is owned by the guest handle and must not be freed.

(Added in 0.3)

guestfs_get_pgroup¶

 int
 guestfs_get_pgroup (guestfs_h *g);

This returns the process group flag.

This function returns a C truth value on success or -1 on error.

(Added in 1.11.18)

guestfs_get_pid¶

 int
 guestfs_get_pid (guestfs_h *g);

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.

On error this function returns -1.

(Added in 1.0.56)

guestfs_get_program¶

 const char *
 guestfs_get_program (guestfs_h *g);

Get the program name. See "guestfs_set_program".

This function returns a string, or NULL on error. The string is owned by the guest handle and must not be freed.

(Added in 1.21.29)

guestfs_get_qemu¶

 const char *
 guestfs_get_qemu (guestfs_h *g);

This function is deprecated. In new code, use the "guestfs_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.

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 returns a string, or NULL on error. The string is owned by the guest handle and must not be freed.

(Added in 1.0.6)

guestfs_get_recovery_proc¶

 int
 guestfs_get_recovery_proc (guestfs_h *g);

Return the recovery process enabled flag.

This function returns a C truth value on success or -1 on error.

(Added in 1.0.77)

guestfs_get_selinux¶

 int
 guestfs_get_selinux (guestfs_h *g);

This function is deprecated. In new code, use the "guestfs_selinux_relabel" 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.

This returns the current setting of the selinux flag which is passed to the appliance at boot time. See "guestfs_set_selinux".

For more information on the architecture of libguestfs, see guestfs(3).

This function returns a C truth value on success or -1 on error.

(Added in 1.0.67)

guestfs_get_smp¶

 int
 guestfs_get_smp (guestfs_h *g);

This returns the number of virtual CPUs assigned to the appliance.

On error this function returns -1.

(Added in 1.13.15)

guestfs_get_sockdir¶

 char *
 guestfs_get_sockdir (guestfs_h *g);

Get the directory used by the handle to store temporary socket and PID files.

This is different from "guestfs_get_tmpdir", as we need shorter paths for sockets (due to the limited buffers of filenames for UNIX sockets), and "guestfs_get_tmpdir" may be too long for them. Furthermore, sockets and PID files must be accessible to such background services started by libguestfs that may not have permission to access the temporary directory returned by "guestfs_get_tmpdir".

The environment variable "XDG_RUNTIME_DIR" controls the default value: If "XDG_RUNTIME_DIR" is set, then that is the default. Else /tmp is the default.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.33.8)

guestfs_get_state¶

 int
 guestfs_get_state (guestfs_h *g);

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).

On error this function returns -1.

(Added in 1.0.2)

guestfs_get_tmpdir¶

 char *
 guestfs_get_tmpdir (guestfs_h *g);

Get the directory used by the handle to store temporary files.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.19.58)

guestfs_get_trace¶

 int
 guestfs_get_trace (guestfs_h *g);

Return the command trace flag.

This function returns a C truth value on success or -1 on error.

(Added in 1.0.69)

guestfs_get_umask¶

 int
 guestfs_get_umask (guestfs_h *g);

Return the current umask. By default the umask is 022 unless it has been set by calling "guestfs_umask".

On error this function returns -1.

(Added in 1.3.4)

guestfs_get_verbose¶

 int
 guestfs_get_verbose (guestfs_h *g);

This returns the verbose messages flag.

This function returns a C truth value on success or -1 on error.

(Added in 0.3)

guestfs_getcon¶

 char *
 guestfs_getcon (guestfs_h *g);

This function is deprecated. In new code, use the "guestfs_selinux_relabel" 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.

This gets the SELinux security context of the daemon.

See the documentation about SELINUX in guestfs(3), and "guestfs_setcon"

This function returns a string, or NULL on error. The caller must free the returned string after use.

This function depends on the feature "selinux". See also "guestfs_feature_available".

(Added in 1.0.67)

guestfs_getxattr¶

 char *
 guestfs_getxattr (guestfs_h *g,
                   const char *path,
                   const char *name,
                   size_t *size_r);

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 "guestfs_lgetxattr".

Normally it is better to get all extended attributes from a file in one go by calling "guestfs_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: "guestfs_getxattrs", "guestfs_lgetxattr", attr(5).

This function returns a buffer, or NULL on error. The size of the returned buffer is written to *size_r. The caller must free the returned buffer after use.

This function depends on the feature "linuxxattrs". See also "guestfs_feature_available".

(Added in 1.7.24)

guestfs_getxattrs¶

 struct guestfs_xattr_list *
 guestfs_getxattrs (guestfs_h *g,
                    const char *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: "guestfs_lgetxattrs", attr(5).

This function returns a "struct guestfs_xattr_list *", or NULL if there was an error. The caller must call "guestfs_free_xattr_list" after use.

This function depends on the feature "linuxxattrs". See also "guestfs_feature_available".

(Added in 1.0.59)

guestfs_glob_expand¶

 char **
 guestfs_glob_expand (guestfs_h *g,
                      const char *pattern);

This function is provided for backwards compatibility with earlier versions of libguestfs. It simply calls "guestfs_glob_expand_opts" with no optional arguments.

(Added in 1.0.50)

guestfs_glob_expand_opts¶

 char **
 guestfs_glob_expand_opts (guestfs_h *g,
                           const char *pattern,
                           ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_GLOB_EXPAND_OPTS_DIRECTORYSLASH, int directoryslash,

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.

"directoryslash" controls whether use the "GLOB_MARK" flag for glob(3), and it defaults to true. It can be explicitly set as off to return no trailing slashes in filenames of directories.

Notice that there is no equivalent command for expanding a device name (eg. /dev/sd*). Use "guestfs_list_devices", "guestfs_list_partitions" etc functions instead.

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

(Added in 1.0.50)

guestfs_glob_expand_opts_va¶

 char **
 guestfs_glob_expand_opts_va (guestfs_h *g,
                              const char *pattern,
                              va_list args);

This is the "va_list variant" of "guestfs_glob_expand_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_glob_expand_opts_argv¶

 char **
 guestfs_glob_expand_opts_argv (guestfs_h *g,
                                const char *pattern,
                                const struct guestfs_glob_expand_opts_argv *optargs);

This is the "argv variant" of "guestfs_glob_expand_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_grep¶

 char **
 guestfs_grep (guestfs_h *g,
               const char *regex,
               const char *path);

This function is provided for backwards compatibility with earlier versions of libguestfs. It simply calls "guestfs_grep_opts" with no optional arguments.

(Added in 1.0.66)

guestfs_grep_opts¶

 char **
 guestfs_grep_opts (guestfs_h *g,
                    const char *regex,
                    const char *path,
                    ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_GREP_OPTS_EXTENDED, int extended,
 GUESTFS_GREP_OPTS_FIXED, int fixed,
 GUESTFS_GREP_OPTS_INSENSITIVE, int insensitive,
 GUESTFS_GREP_OPTS_COMPRESSED, int compressed,

This calls the external grep(1) 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(1) instead of grep(1). This allows the input to be compress- or gzip-compressed.

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

Because of the message protocol, there is a transfer limit of somewhere between 2MB and 4MB. See "PROTOCOL LIMITS".

(Added in 1.0.66)

guestfs_grep_opts_va¶

 char **
 guestfs_grep_opts_va (guestfs_h *g,
                       const char *regex,
                       const char *path,
                       va_list args);

This is the "va_list variant" of "guestfs_grep_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_grep_opts_argv¶

 char **
 guestfs_grep_opts_argv (guestfs_h *g,
                         const char *regex,
                         const char *path,
                         const struct guestfs_grep_opts_argv *optargs);

This is the "argv variant" of "guestfs_grep_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_grepi¶

 char **
 guestfs_grepi (guestfs_h *g,
                const char *regex,
                const char *path);

This function is deprecated. In new code, use the "guestfs_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.

This calls the external "grep -i" program and returns the matching lines.

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

Because of the message protocol, there is a transfer limit of somewhere between 2MB and 4MB. See "PROTOCOL LIMITS".

(Added in 1.0.66)

guestfs_grub_install¶

 int
 guestfs_grub_install (guestfs_h *g,
                       const char *root,
                       const char *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".
• This uses grub-install(8) 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.

This function returns 0 on success or -1 on error.

This function depends on the feature "grub". See also "guestfs_feature_available".

(Added in 1.0.17)

guestfs_head¶

 char **
 guestfs_head (guestfs_h *g,
               const char *path);

This command returns up to the first 10 lines of a file as a list of strings.

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

Because of the message protocol, there is a transfer limit of somewhere between 2MB and 4MB. See "PROTOCOL LIMITS".

(Added in 1.0.54)

guestfs_head_n¶

 char **
 guestfs_head_n (guestfs_h *g,
                 int nrlines,
                 const char *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.

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

Because of the message protocol, there is a transfer limit of somewhere between 2MB and 4MB. See "PROTOCOL LIMITS".

(Added in 1.0.54)

guestfs_hexdump¶

 char *
 guestfs_hexdump (guestfs_h *g,
                  const char *path);

This runs "hexdump -C" on the given "path". The result is the human-readable, canonical hex dump of the file.

This function returns a string, or NULL on error. The caller must free the returned string after use.

Because of the message protocol, there is a transfer limit of somewhere between 2MB and 4MB. See "PROTOCOL LIMITS".

(Added in 1.0.22)

guestfs_hivex_close¶

 int
 guestfs_hivex_close (guestfs_h *g);

Close the current hivex handle.

This is a wrapper around the hivex(3) call of the same name.

This function returns 0 on success or -1 on error.

This function depends on the feature "hivex". See also "guestfs_feature_available".

(Added in 1.19.35)

guestfs_hivex_commit¶

 int
 guestfs_hivex_commit (guestfs_h *g,
                       const char *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.

This function returns 0 on success or -1 on error.

This function depends on the feature "hivex". See also "guestfs_feature_available".

(Added in 1.19.35)

guestfs_hivex_node_add_child¶

 int64_t
 guestfs_hivex_node_add_child (guestfs_h *g,
                               int64_t parent,
                               const char *name);

Add a child node to "parent" named "name".

This is a wrapper around the hivex(3) call of the same name.

On error this function returns -1.

This function depends on the feature "hivex". See also "guestfs_feature_available".

(Added in 1.19.35)

guestfs_hivex_node_children¶

 struct guestfs_hivex_node_list *
 guestfs_hivex_node_children (guestfs_h *g,
                              int64_t nodeh);

Return the list of nodes which are subkeys of "nodeh".

This is a wrapper around the hivex(3) call of the same name.

This function returns a "struct guestfs_hivex_node_list *", or NULL if there was an error. The caller must call "guestfs_free_hivex_node_list" after use.

This function depends on the feature "hivex". See also "guestfs_feature_available".

(Added in 1.19.35)

guestfs_hivex_node_delete_child¶

 int
 guestfs_hivex_node_delete_child (guestfs_h *g,
                                  int64_t nodeh);

Delete "nodeh", recursively if necessary.

This is a wrapper around the hivex(3) call of the same name.

This function returns 0 on success or -1 on error.

This function depends on the feature "hivex". See also "guestfs_feature_available".

(Added in 1.19.35)

guestfs_hivex_node_get_child¶

 int64_t
 guestfs_hivex_node_get_child (guestfs_h *g,
                               int64_t nodeh,
                               const char *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.

On error this function returns -1.

This function depends on the feature "hivex". See also "guestfs_feature_available".

(Added in 1.19.35)

guestfs_hivex_node_get_value¶

 int64_t
 guestfs_hivex_node_get_value (guestfs_h *g,
                               int64_t nodeh,
                               const char *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.

On error this function returns -1.

This function depends on the feature "hivex". See also "guestfs_feature_available".

(Added in 1.19.35)

guestfs_hivex_node_name¶

 char *
 guestfs_hivex_node_name (guestfs_h *g,
                          int64_t nodeh);

Return the name of "nodeh".

This is a wrapper around the hivex(3) call of the same name.

This function returns a string, or NULL on error. The caller must free the returned string after use.

This function depends on the feature "hivex". See also "guestfs_feature_available".

(Added in 1.19.35)

guestfs_hivex_node_parent¶

 int64_t
 guestfs_hivex_node_parent (guestfs_h *g,
                            int64_t nodeh);

Return the parent node of "nodeh".

This is a wrapper around the hivex(3) call of the same name.

On error this function returns -1.

This function depends on the feature "hivex". See also "guestfs_feature_available".

(Added in 1.19.35)

guestfs_hivex_node_set_value¶

 int
 guestfs_hivex_node_set_value (guestfs_h *g,
                               int64_t nodeh,
                               const char *key,
                               int64_t t,
                               const char *val,
                               size_t val_size);

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.

This function returns 0 on success or -1 on error.

This function depends on the feature "hivex". See also "guestfs_feature_available".

(Added in 1.19.35)

guestfs_hivex_node_values¶

 struct guestfs_hivex_value_list *
 guestfs_hivex_node_values (guestfs_h *g,
                            int64_t 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.

This function returns a "struct guestfs_hivex_value_list *", or NULL if there was an error. The caller must call "guestfs_free_hivex_value_list" after use.

This function depends on the feature "hivex". See also "guestfs_feature_available".

(Added in 1.19.35)

guestfs_hivex_open¶

 int
 guestfs_hivex_open (guestfs_h *g,
                     const char *filename,
                     ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_HIVEX_OPEN_VERBOSE, int verbose,
 GUESTFS_HIVEX_OPEN_DEBUG, int debug,
 GUESTFS_HIVEX_OPEN_WRITE, int write,
 GUESTFS_HIVEX_OPEN_UNSAFE, int unsafe,

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.

This function returns 0 on success or -1 on error.

This function depends on the feature "hivex". See also "guestfs_feature_available".

(Added in 1.19.35)

guestfs_hivex_open_va¶

 int
 guestfs_hivex_open_va (guestfs_h *g,
                        const char *filename,
                        va_list args);

This is the "va_list variant" of "guestfs_hivex_open".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_hivex_open_argv¶

 int
 guestfs_hivex_open_argv (guestfs_h *g,
                          const char *filename,
                          const struct guestfs_hivex_open_argv *optargs);

This is the "argv variant" of "guestfs_hivex_open".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_hivex_root¶

 int64_t
 guestfs_hivex_root (guestfs_h *g);

Return the root node of the hive.

This is a wrapper around the hivex(3) call of the same name.

On error this function returns -1.

This function depends on the feature "hivex". See also "guestfs_feature_available".

(Added in 1.19.35)

guestfs_hivex_value_key¶

 char *
 guestfs_hivex_value_key (guestfs_h *g,
                          int64_t 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.

This function returns a string, or NULL on error. The caller must free the returned string after use.

This function depends on the feature "hivex". See also "guestfs_feature_available".

(Added in 1.19.35)

guestfs_hivex_value_string¶

 char *
 guestfs_hivex_value_string (guestfs_h *g,
                             int64_t valueh);

This calls "guestfs_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.

This function returns a string, or NULL on error. The caller must free the returned string after use.

This function depends on the feature "hivex". See also "guestfs_feature_available".

(Added in 1.37.22)

guestfs_hivex_value_type¶

 int64_t
 guestfs_hivex_value_type (guestfs_h *g,
                           int64_t 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.

On error this function returns -1.

This function depends on the feature "hivex". See also "guestfs_feature_available".

(Added in 1.19.35)

guestfs_hivex_value_utf8¶

 char *
 guestfs_hivex_value_utf8 (guestfs_h *g,
                           int64_t valueh);

This function is deprecated. In new code, use the "guestfs_hivex_value_string" 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.

This calls "guestfs_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.

This function returns a string, or NULL on error. The caller must free the returned string after use.

This function depends on the feature "hivex". See also "guestfs_feature_available".

(Added in 1.19.35)

guestfs_hivex_value_value¶

 char *
 guestfs_hivex_value_value (guestfs_h *g,
                            int64_t valueh,
                            size_t *size_r);

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: "guestfs_hivex_value_utf8".

This function returns a buffer, or NULL on error. The size of the returned buffer is written to *size_r. The caller must free the returned buffer after use.

This function depends on the feature "hivex". See also "guestfs_feature_available".

(Added in 1.19.35)

guestfs_initrd_cat¶

 char *
 guestfs_initrd_cat (guestfs_h *g,
                     const char *initrdpath,
                     const char *filename,
                     size_t *size_r);

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 "guestfs_initrd_list".

This function returns a buffer, or NULL on error. The size of the returned buffer is written to *size_r. The caller must free the returned buffer after use.

Because of the message protocol, there is a transfer limit of somewhere between 2MB and 4MB. See "PROTOCOL LIMITS".

(Added in 1.0.84)

guestfs_initrd_list¶

 char **
 guestfs_initrd_list (guestfs_h *g,
                      const char *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).

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

(Added in 1.0.54)

guestfs_inotify_add_watch¶

 int64_t
 guestfs_inotify_add_watch (guestfs_h *g,
                            const char *path,
                            int 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.

On error this function returns -1.

This function depends on the feature "inotify". See also "guestfs_feature_available".

(Added in 1.0.66)

guestfs_inotify_close¶

 int
 guestfs_inotify_close (guestfs_h *g);

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.

This function returns 0 on success or -1 on error.

This function depends on the feature "inotify". See also "guestfs_feature_available".

(Added in 1.0.66)

guestfs_inotify_files¶

 char **
 guestfs_inotify_files (guestfs_h *g);

This function is a helpful wrapper around "guestfs_inotify_read" which just returns a list of pathnames of objects that were touched. The returned pathnames are sorted and deduplicated.

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

This function depends on the feature "inotify". See also "guestfs_feature_available".

(Added in 1.0.66)

guestfs_inotify_init¶

 int
 guestfs_inotify_init (guestfs_h *g,
                       int 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 "guestfs_inotify_read" or "guestfs_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 "guestfs_inotify_read").

Before any events are generated, you have to add some watches to the internal watch list. See: "guestfs_inotify_add_watch" and "guestfs_inotify_rm_watch".

Queued up events should be read periodically by calling "guestfs_inotify_read" (or "guestfs_inotify_files" which is just a helpful wrapper around "guestfs_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 "guestfs_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.

This function returns 0 on success or -1 on error.

This function depends on the feature "inotify". See also "guestfs_feature_available".

(Added in 1.0.66)

guestfs_inotify_read¶

 struct guestfs_inotify_event_list *
 guestfs_inotify_read (guestfs_h *g);

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.

This function returns a "struct guestfs_inotify_event_list *", or NULL if there was an error. The caller must call "guestfs_free_inotify_event_list" after use.

This function depends on the feature "inotify". See also "guestfs_feature_available".

(Added in 1.0.66)

guestfs_inotify_rm_watch¶

 int
 guestfs_inotify_rm_watch (guestfs_h *g,
                           int wd);

Remove a previously defined inotify watch. See "guestfs_inotify_add_watch".

This function returns 0 on success or -1 on error.

This function depends on the feature "inotify". See also "guestfs_feature_available".

(Added in 1.0.66)

guestfs_inspect_get_arch¶

 char *
 guestfs_inspect_get_arch (guestfs_h *g,
                           const char *root);

This returns the architecture of the inspected operating system. The possible return values are listed under "guestfs_file_architecture".

If the architecture could not be determined, then the string "unknown" is returned.

Please read "INSPECTION" for more details.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.5.3)

guestfs_inspect_get_build_id¶

 char *
 guestfs_inspect_get_build_id (guestfs_h *g,
                               const char *root);

This returns the build ID of the system, or the string "unknown" if the system does not have a build ID.

For Windows, this gets the build number. Although it is returned as a string, it is (so far) always a number. See https://en.wikipedia.org/wiki/List_of_Microsoft_Windows_versions for some possible values.

For Linux, this returns the "BUILD_ID" string from /etc/os-release, although this is not often used.

Please read "INSPECTION" for more details.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.49.8)

guestfs_inspect_get_distro¶

 char *
 guestfs_inspect_get_distro (guestfs_h *g,
                             const char *root);

This returns the distro (distribution) of the inspected operating system.

Currently defined distros are:

"alpinelinux"

Alpine Linux.

"altlinux"

ALT Linux.

"archlinux"

Arch Linux.

"buildroot"

Buildroot-derived distro, but not one we specifically recognize.

"centos"

CentOS.

"circle"

Circle Linux.

"cirros"

Cirros.

"coreos"

CoreOS.

"debian"

Debian.

"fedora"

Fedora.

"freebsd"

FreeBSD.

"freedos"

FreeDOS.

"frugalware"

Frugalware.

"gentoo"

Gentoo.

"kalilinux"

Kali Linux.

"kylin"

Kylin.

"linuxmint"

Linux Mint.

"mageia"

Mageia.

"mandriva"

Mandriva.

"meego"

MeeGo.

"msdos"

Microsoft DOS.

"neokylin"

NeoKylin.

"netbsd"

NetBSD.

"openbsd"

OpenBSD.

"openeuler"

openEuler.

"openmandriva"

OpenMandriva Lx.

"opensuse"

OpenSUSE.

"oraclelinux"

Oracle Linux.

"pardus"

Pardus.

"pldlinux"

PLD Linux.

"redhat-based"

Some Red Hat-derived distro.

"rhel"

Red Hat Enterprise Linux.

"rocky"

Rocky 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.

"voidlinux"

Void Linux.

"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" for more details.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.5.3)

guestfs_inspect_get_drive_mappings¶

 char **
 guestfs_inspect_get_drive_mappings (guestfs_h *g,
                                     const char *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" for more details. See also "guestfs_inspect_get_mountpoints", "guestfs_inspect_get_filesystems".

This function returns a NULL-terminated array of strings, or NULL if there was an error. The array of strings will always have length "2n+1", where "n" keys and values alternate, followed by the trailing NULL entry. The caller must free the strings and the array after use.

(Added in 1.9.17)

guestfs_inspect_get_filesystems¶

 char **
 guestfs_inspect_get_filesystems (guestfs_h *g,
                                  const char *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" for more details. See also "guestfs_inspect_get_mountpoints".

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

(Added in 1.5.3)

guestfs_inspect_get_format¶

 char *
 guestfs_inspect_get_format (guestfs_h *g,
                             const char *root);

This function is deprecated. There is no replacement. Consult the API documentation in guestfs(3) for further information.

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.

Before libguestfs 1.38, there was some unreliable support for detecting installer CDs. This API would return:

"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.

In libguestfs ≥ 1.38, this only returns "installed". Use libosinfo directly to detect installer CDs.

Please read "INSPECTION" for more details.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.9.4)

guestfs_inspect_get_hostname¶

 char *
 guestfs_inspect_get_hostname (guestfs_h *g,
                               const char *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" for more details.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.7.9)

guestfs_inspect_get_icon¶

 char *
 guestfs_inspect_get_icon (guestfs_h *g,
                           const char *root,
                           size_t *size_r,
                           ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_INSPECT_GET_ICON_FAVICON, int favicon,
 GUESTFS_INSPECT_GET_ICON_HIGHQUALITY, int 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(1) program from the "icoutils" package, and several programs (bmptopnm(1), pnmtopng(1), pamcut(1)) from the "netpbm" package. These must be installed separately.
• Operating system icons are usually trademarks. Seek legal advice before using trademarks in applications.

This function returns a buffer, or NULL on error. The size of the returned buffer is written to *size_r. The caller must free the returned buffer after use.

(Added in 1.11.12)

guestfs_inspect_get_icon_va¶

 char *
 guestfs_inspect_get_icon_va (guestfs_h *g,
                              const char *root,
                              size_t *size_r,
                              va_list args);

This is the "va_list variant" of "guestfs_inspect_get_icon".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_inspect_get_icon_argv¶

 char *
 guestfs_inspect_get_icon_argv (guestfs_h *g,
                                const char *root,
                                size_t *size_r,
                                const struct guestfs_inspect_get_icon_argv *optargs);

This is the "argv variant" of "guestfs_inspect_get_icon".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_inspect_get_major_version¶

 int
 guestfs_inspect_get_major_version (guestfs_h *g,
                                    const char *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" for more details.

On error this function returns -1.

(Added in 1.5.3)

guestfs_inspect_get_minor_version¶

 int
 guestfs_inspect_get_minor_version (guestfs_h *g,
                                    const char *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" for more details. See also "guestfs_inspect_get_major_version".

On error this function returns -1.

(Added in 1.5.3)

guestfs_inspect_get_mountpoints¶

 char **
 guestfs_inspect_get_mountpoints (guestfs_h *g,
                                  const char *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 "guestfs_inspect_get_drive_mappings".

Please read "INSPECTION" for more details. See also "guestfs_inspect_get_filesystems".

This function returns a NULL-terminated array of strings, or NULL if there was an error. The array of strings will always have length "2n+1", where "n" keys and values alternate, followed by the trailing NULL entry. The caller must free the strings and the array after use.

(Added in 1.5.3)

guestfs_inspect_get_osinfo¶

 char *
 guestfs_inspect_get_osinfo (guestfs_h *g,
                             const char *root);

This function returns a possible short ID for libosinfo corresponding to the guest.

Note: The returned ID is only a guess by libguestfs, and nothing ensures that it actually exists in osinfo-db.

If no ID could not be determined, then the string "unknown" is returned.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.39.1)

guestfs_inspect_get_package_format¶

 char *
 guestfs_inspect_get_package_format (guestfs_h *g,
                                     const char *root);

This function and "guestfs_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" or "dnf" (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", "apk", "xbps". Future versions of libguestfs may return other strings.

Please read "INSPECTION" for more details.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.7.5)

guestfs_inspect_get_package_management¶

 char *
 guestfs_inspect_get_package_management (guestfs_h *g,
                                         const char *root);

"guestfs_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" or "dnf" (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", "dnf", "up2date", "apt" (for all Debian derivatives), "portage", "pisi", "pacman", "urpmi", "zypper", "apk", "xbps". Future versions of libguestfs may return other strings.

Please read "INSPECTION" for more details.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.7.5)

guestfs_inspect_get_product_name¶

 char *
 guestfs_inspect_get_product_name (guestfs_h *g,
                                   const char *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" for more details.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.5.3)

guestfs_inspect_get_product_variant¶

 char *
 guestfs_inspect_get_product_variant (guestfs_h *g,
                                      const char *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" for more details. See also "guestfs_inspect_get_product_name", "guestfs_inspect_get_major_version".

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.9.13)

guestfs_inspect_get_roots¶

 char **
 guestfs_inspect_get_roots (guestfs_h *g);

This function is a convenient way to get the list of root devices, as returned from a previous call to "guestfs_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 "guestfs_inspect_os".

Please read "INSPECTION" for more details.

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

(Added in 1.7.3)

guestfs_inspect_get_type¶

 char *
 guestfs_inspect_get_type (guestfs_h *g,
                           const char *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.

"minix"

MINIX.

"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" for more details.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.5.3)

guestfs_inspect_get_windows_current_control_set¶

 char *
 guestfs_inspect_get_windows_current_control_set (guestfs_h *g,
                                                  const char *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" for more details.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.9.17)

guestfs_inspect_get_windows_software_hive¶

 char *
 guestfs_inspect_get_windows_software_hive (guestfs_h *g,
                                            const char *root);

This returns the path to the hive (binary Windows Registry file) corresponding to HKLM\SOFTWARE.

This call assumes that the guest is Windows and that the guest has a software hive file with the right name. If this is not the case then an error is returned. This call does not check that the hive is a valid Windows Registry hive.

You can use "guestfs_hivex_open" to read or write to the hive.

Please read "INSPECTION" for more details.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.35.26)

guestfs_inspect_get_windows_system_hive¶

 char *
 guestfs_inspect_get_windows_system_hive (guestfs_h *g,
                                          const char *root);

This returns the path to the hive (binary Windows Registry file) corresponding to HKLM\SYSTEM.

This call assumes that the guest is Windows and that the guest has a system hive file with the right name. If this is not the case then an error is returned. This call does not check that the hive is a valid Windows Registry hive.

You can use "guestfs_hivex_open" to read or write to the hive.

Please read "INSPECTION" for more details.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.35.26)

guestfs_inspect_get_windows_systemroot¶

 char *
 guestfs_inspect_get_windows_systemroot (guestfs_h *g,
                                         const char *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" for more details.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.5.25)

guestfs_inspect_is_live¶

 int
 guestfs_inspect_is_live (guestfs_h *g,
                          const char *root);

This function is deprecated. There is no replacement. Consult the API documentation in guestfs(3) for further information.

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.

This is deprecated and always returns "false".

Please read "INSPECTION" for more details.

This function returns a C truth value on success or -1 on error.

(Added in 1.9.4)

guestfs_inspect_is_multipart¶

 int
 guestfs_inspect_is_multipart (guestfs_h *g,
                               const char *root);

This function is deprecated. There is no replacement. Consult the API documentation in guestfs(3) for further information.

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.

This is deprecated and always returns "false".

Please read "INSPECTION" for more details.

This function returns a C truth value on success or -1 on error.

(Added in 1.9.4)

guestfs_inspect_is_netinst¶

 int
 guestfs_inspect_is_netinst (guestfs_h *g,
                             const char *root);

This function is deprecated. There is no replacement. Consult the API documentation in guestfs(3) for further information.

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.

This is deprecated and always returns "false".

Please read "INSPECTION" for more details.

This function returns a C truth value on success or -1 on error.

(Added in 1.9.4)

guestfs_inspect_list_applications¶

 struct guestfs_application_list *
 guestfs_inspect_list_applications (guestfs_h *g,
                                    const char *root);

This function is deprecated. In new code, use the "guestfs_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.

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 "guestfs_inspect_os", then "guestfs_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 "guestfs_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 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" for more details.

This function returns a "struct guestfs_application_list *", or NULL if there was an error. The caller must call "guestfs_free_application_list" after use.

(Added in 1.7.8)

guestfs_inspect_list_applications2¶

 struct guestfs_application2_list *
 guestfs_inspect_list_applications2 (guestfs_h *g,
                                     const char *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 "guestfs_inspect_os", then "guestfs_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 "guestfs_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 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" for more details.

This function returns a "struct guestfs_application2_list *", or NULL if there was an error. The caller must call "guestfs_free_application2_list" after use.

(Added in 1.19.56)

guestfs_inspect_os¶

 char **
 guestfs_inspect_os (guestfs_h *g);

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 "guestfs_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 "guestfs_mount_ro" and "guestfs_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" for more details.

See also "guestfs_list_filesystems".

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

(Added in 1.5.3)

guestfs_is_blockdev¶

 int
 guestfs_is_blockdev (guestfs_h *g,
                      const char *path);

This function is provided for backwards compatibility with earlier versions of libguestfs. It simply calls "guestfs_is_blockdev_opts" with no optional arguments.

(Added in 1.5.10)

guestfs_is_blockdev_opts¶

 int
 guestfs_is_blockdev_opts (guestfs_h *g,
                           const char *path,
                           ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_IS_BLOCKDEV_OPTS_FOLLOWSYMLINKS, int 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.

This call only looks at files within the guest filesystem. Libguestfs partitions and block devices (eg. /dev/sda) cannot be used as the "path" parameter of this call.

See also "guestfs_stat".

This function returns a C truth value on success or -1 on error.

(Added in 1.5.10)

guestfs_is_blockdev_opts_va¶

 int
 guestfs_is_blockdev_opts_va (guestfs_h *g,
                              const char *path,
                              va_list args);

This is the "va_list variant" of "guestfs_is_blockdev_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_is_blockdev_opts_argv¶

 int
 guestfs_is_blockdev_opts_argv (guestfs_h *g,
                                const char *path,
                                const struct guestfs_is_blockdev_opts_argv *optargs);

This is the "argv variant" of "guestfs_is_blockdev_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_is_busy¶

 int
 guestfs_is_busy (guestfs_h *g);

This always returns false. This function is deprecated with no replacement. Do not use this function.

For more information on states, see guestfs(3).

This function returns a C truth value on success or -1 on error.

(Added in 1.0.2)

guestfs_is_chardev¶

 int
 guestfs_is_chardev (guestfs_h *g,
                     const char *path);

This function is provided for backwards compatibility with earlier versions of libguestfs. It simply calls "guestfs_is_chardev_opts" with no optional arguments.

(Added in 1.5.10)

guestfs_is_chardev_opts¶

 int
 guestfs_is_chardev_opts (guestfs_h *g,
                          const char *path,
                          ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_IS_CHARDEV_OPTS_FOLLOWSYMLINKS, int 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 "guestfs_stat".

This function returns a C truth value on success or -1 on error.

(Added in 1.5.10)

guestfs_is_chardev_opts_va¶

 int
 guestfs_is_chardev_opts_va (guestfs_h *g,
                             const char *path,
                             va_list args);

This is the "va_list variant" of "guestfs_is_chardev_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_is_chardev_opts_argv¶

 int
 guestfs_is_chardev_opts_argv (guestfs_h *g,
                               const char *path,
                               const struct guestfs_is_chardev_opts_argv *optargs);

This is the "argv variant" of "guestfs_is_chardev_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_is_config¶

 int
 guestfs_is_config (guestfs_h *g);

This returns true iff this handle is being configured (in the "CONFIG" state).

For more information on states, see guestfs(3).

This function returns a C truth value on success or -1 on error.

(Added in 1.0.2)

guestfs_is_dir¶

 int
 guestfs_is_dir (guestfs_h *g,
                 const char *path);

This function is provided for backwards compatibility with earlier versions of libguestfs. It simply calls "guestfs_is_dir_opts" with no optional arguments.

(Added in 0.8)

guestfs_is_dir_opts¶

 int
 guestfs_is_dir_opts (guestfs_h *g,
                      const char *path,
                      ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_IS_DIR_OPTS_FOLLOWSYMLINKS, int 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 "guestfs_stat".

This function returns a C truth value on success or -1 on error.

(Added in 0.8)

guestfs_is_dir_opts_va¶

 int
 guestfs_is_dir_opts_va (guestfs_h *g,
                         const char *path,
                         va_list args);

This is the "va_list variant" of "guestfs_is_dir_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_is_dir_opts_argv¶

 int
 guestfs_is_dir_opts_argv (guestfs_h *g,
                           const char *path,
                           const struct guestfs_is_dir_opts_argv *optargs);

This is the "argv variant" of "guestfs_is_dir_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_is_fifo¶

 int
 guestfs_is_fifo (guestfs_h *g,
                  const char *path);

This function is provided for backwards compatibility with earlier versions of libguestfs. It simply calls "guestfs_is_fifo_opts" with no optional arguments.

(Added in 1.5.10)

guestfs_is_fifo_opts¶

 int
 guestfs_is_fifo_opts (guestfs_h *g,
                       const char *path,
                       ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_IS_FIFO_OPTS_FOLLOWSYMLINKS, int 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 "guestfs_stat".

This function returns a C truth value on success or -1 on error.

(Added in 1.5.10)

guestfs_is_fifo_opts_va¶

 int
 guestfs_is_fifo_opts_va (guestfs_h *g,
                          const char *path,
                          va_list args);

This is the "va_list variant" of "guestfs_is_fifo_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_is_fifo_opts_argv¶

 int
 guestfs_is_fifo_opts_argv (guestfs_h *g,
                            const char *path,
                            const struct guestfs_is_fifo_opts_argv *optargs);

This is the "argv variant" of "guestfs_is_fifo_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_is_file¶

 int
 guestfs_is_file (guestfs_h *g,
                  const char *path);

This function is provided for backwards compatibility with earlier versions of libguestfs. It simply calls "guestfs_is_file_opts" with no optional arguments.

(Added in 0.8)

guestfs_is_file_opts¶

 int
 guestfs_is_file_opts (guestfs_h *g,
                       const char *path,
                       ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_IS_FILE_OPTS_FOLLOWSYMLINKS, int 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 "guestfs_stat".

This function returns a C truth value on success or -1 on error.

(Added in 0.8)

guestfs_is_file_opts_va¶

 int
 guestfs_is_file_opts_va (guestfs_h *g,
                          const char *path,
                          va_list args);

This is the "va_list variant" of "guestfs_is_file_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_is_file_opts_argv¶

 int
 guestfs_is_file_opts_argv (guestfs_h *g,
                            const char *path,
                            const struct guestfs_is_file_opts_argv *optargs);

This is the "argv variant" of "guestfs_is_file_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_is_launching¶

 int
 guestfs_is_launching (guestfs_h *g);

This returns true iff this handle is launching the subprocess (in the "LAUNCHING" state).

For more information on states, see guestfs(3).

This function returns a C truth value on success or -1 on error.

(Added in 1.0.2)

guestfs_is_lv¶

 int
 guestfs_is_lv (guestfs_h *g,
                const char *mountable);

This command tests whether "mountable" is a logical volume, and returns true iff this is the case.

This function returns a C truth value on success or -1 on error.

(Added in 1.5.3)

guestfs_is_ready¶

 int
 guestfs_is_ready (guestfs_h *g);

This returns true iff this handle is ready to accept commands (in the "READY" state).

For more information on states, see guestfs(3).

This function returns a C truth value on success or -1 on error.

(Added in 1.0.2)

guestfs_is_socket¶

 int
 guestfs_is_socket (guestfs_h *g,
                    const char *path);

This function is provided for backwards compatibility with earlier versions of libguestfs. It simply calls "guestfs_is_socket_opts" with no optional arguments.

(Added in 1.5.10)

guestfs_is_socket_opts¶

 int
 guestfs_is_socket_opts (guestfs_h *g,
                         const char *path,
                         ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_IS_SOCKET_OPTS_FOLLOWSYMLINKS, int 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 "guestfs_stat".

This function returns a C truth value on success or -1 on error.

(Added in 1.5.10)

guestfs_is_socket_opts_va¶

 int
 guestfs_is_socket_opts_va (guestfs_h *g,
                            const char *path,
                            va_list args);

This is the "va_list variant" of "guestfs_is_socket_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_is_socket_opts_argv¶

 int
 guestfs_is_socket_opts_argv (guestfs_h *g,
                              const char *path,
                              const struct guestfs_is_socket_opts_argv *optargs);

This is the "argv variant" of "guestfs_is_socket_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_is_symlink¶

 int
 guestfs_is_symlink (guestfs_h *g,
                     const char *path);

This returns "true" if and only if there is a symbolic link with the given "path" name.

See also "guestfs_stat".

This function returns a C truth value on success or -1 on error.

(Added in 1.5.10)

guestfs_is_whole_device¶

 int
 guestfs_is_whole_device (guestfs_h *g,
                          const char *device);

This returns "true" if and only if "device" refers to a whole block device. That is, not a partition or a logical device.

This function returns a C truth value on success or -1 on error.

(Added in 1.21.9)

guestfs_is_zero¶

 int
 guestfs_is_zero (guestfs_h *g,
                  const char *path);

This returns true iff the file exists and the file is empty or it contains all zero bytes.

This function returns a C truth value on success or -1 on error.

(Added in 1.11.8)

guestfs_is_zero_device¶

 int
 guestfs_is_zero_device (guestfs_h *g,
                         const char *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.

This function returns a C truth value on success or -1 on error.

(Added in 1.11.8)

guestfs_isoinfo¶

 struct guestfs_isoinfo *
 guestfs_isoinfo (guestfs_h *g,
                  const char *isofile);

This is the same as "guestfs_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 "guestfs_isoinfo_device".

This function returns a "struct guestfs_isoinfo *", or NULL if there was an error. The caller must call "guestfs_free_isoinfo" after use.

(Added in 1.17.19)

guestfs_isoinfo_device¶

 struct guestfs_isoinfo *
 guestfs_isoinfo_device (guestfs_h *g,
                         const char *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 https://wiki.osdev.org/ISO_9660#The_Primary_Volume_Descriptor

This function returns a "struct guestfs_isoinfo *", or NULL if there was an error. The caller must call "guestfs_free_isoinfo" after use.

(Added in 1.17.19)

guestfs_journal_close¶

 int
 guestfs_journal_close (guestfs_h *g);

Close the journal handle.

This function returns 0 on success or -1 on error.

This function depends on the feature "journal". See also "guestfs_feature_available".

(Added in 1.23.11)

guestfs_journal_get¶

 struct guestfs_xattr_list *
 guestfs_journal_get (guestfs_h *g);

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: "guestfs_journal_set_data_threshold", "guestfs_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.

This function returns a "struct guestfs_xattr_list *", or NULL if there was an error. The caller must call "guestfs_free_xattr_list" after use.

This function depends on the feature "journal". See also "guestfs_feature_available".

(Added in 1.23.11)

guestfs_journal_get_data_threshold¶

 int64_t
 guestfs_journal_get_data_threshold (guestfs_h *g);

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 "guestfs_journal_set_data_threshold".

On error this function returns -1.

This function depends on the feature "journal". See also "guestfs_feature_available".

(Added in 1.23.11)

guestfs_journal_get_realtime_usec¶

 int64_t
 guestfs_journal_get_realtime_usec (guestfs_h *g);

Get the realtime (wallclock) timestamp of the current journal entry.

On error this function returns -1.

This function depends on the feature "journal". See also "guestfs_feature_available".

(Added in 1.27.18)

guestfs_journal_next¶

 int
 guestfs_journal_next (guestfs_h *g);

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 "guestfs_journal_get"), and "false" means you have reached the end of the journal.

This function returns a C truth value on success or -1 on error.

This function depends on the feature "journal". See also "guestfs_feature_available".

(Added in 1.23.11)

guestfs_journal_open¶

 int
 guestfs_journal_open (guestfs_h *g,
                       const char *directory);

Open the systemd journal located in directory. Any previously opened journal handle is closed.

The contents of the journal can be read using "guestfs_journal_next" and "guestfs_journal_get".

After you have finished using the journal, you should close the handle by calling "guestfs_journal_close".

This function returns 0 on success or -1 on error.

This function depends on the feature "journal". See also "guestfs_feature_available".

(Added in 1.23.11)

guestfs_journal_set_data_threshold¶

 int
 guestfs_journal_set_data_threshold (guestfs_h *g,
                                     int64_t 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 "guestfs_journal_get_data_threshold".

This function returns 0 on success or -1 on error.

This function depends on the feature "journal". See also "guestfs_feature_available".

(Added in 1.23.11)

guestfs_journal_skip¶

 int64_t
 guestfs_journal_skip (guestfs_h *g,
                       int64_t skip);

Skip forwards ("skip ≥ 0") or backwards ("skip < 0") in the journal.

The number of entries actually skipped is returned (note "rskip ≥ 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.

On error this function returns -1.

This function depends on the feature "journal". See also "guestfs_feature_available".

(Added in 1.23.11)

guestfs_kill_subprocess¶

 int
 guestfs_kill_subprocess (guestfs_h *g);

This function is deprecated. In new code, use the "guestfs_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.

This kills the hypervisor.

Do not call this. See: "guestfs_shutdown" instead.

This function returns 0 on success or -1 on error.

(Added in 0.3)

guestfs_launch¶

 int
 guestfs_launch (guestfs_h *g);

You should call this after configuring the handle (eg. adding drives) but before performing any actions.

Do not call "guestfs_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.

This function returns 0 on success or -1 on error.

This long-running command can generate progress notification messages so that the caller can display a progress bar or indicator. To receive these messages, the caller must register a progress event callback. See "GUESTFS_EVENT_PROGRESS".

(Added in 0.3)

guestfs_lchown¶

 int
 guestfs_lchown (guestfs_h *g,
                 int owner,
                 int group,
                 const char *path);

Change the file owner to "owner" and group to "group". This is like "guestfs_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).

This function returns 0 on success or -1 on error.

(Added in 1.0.77)

guestfs_ldmtool_create_all¶

 int
 guestfs_ldmtool_create_all (guestfs_h *g);

This function scans all block devices looking for Windows dynamic disk volumes and partitions, and creates devices for any that were found.

Call "guestfs_list_ldm_volumes" and "guestfs_list_ldm_partitions" to return all devices.

Note that you don't normally need to call this explicitly, since it is done automatically at "guestfs_launch" time.

This function returns 0 on success or -1 on error.

This function depends on the feature "ldm". See also "guestfs_feature_available".

(Added in 1.20.0)

guestfs_ldmtool_diskgroup_disks¶

 char **
 guestfs_ldmtool_diskgroup_disks (guestfs_h *g,
                                  const char *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 "guestfs_ldmtool_scan".

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

This function depends on the feature "ldm". See also "guestfs_feature_available".

(Added in 1.20.0)

guestfs_ldmtool_diskgroup_name¶

 char *
 guestfs_ldmtool_diskgroup_name (guestfs_h *g,
                                 const char *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 "guestfs_ldmtool_scan".

This function returns a string, or NULL on error. The caller must free the returned string after use.

This function depends on the feature "ldm". See also "guestfs_feature_available".

(Added in 1.20.0)

guestfs_ldmtool_diskgroup_volumes¶

 char **
 guestfs_ldmtool_diskgroup_volumes (guestfs_h *g,
                                    const char *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 "guestfs_ldmtool_scan".

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

This function depends on the feature "ldm". See also "guestfs_feature_available".

(Added in 1.20.0)

guestfs_ldmtool_remove_all¶

 int
 guestfs_ldmtool_remove_all (guestfs_h *g);

This is essentially the opposite of "guestfs_ldmtool_create_all". It removes the device mapper mappings for all Windows dynamic disk volumes

This function returns 0 on success or -1 on error.

This function depends on the feature "ldm". See also "guestfs_feature_available".

(Added in 1.20.0)

guestfs_ldmtool_scan¶

 char **
 guestfs_ldmtool_scan (guestfs_h *g);

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 "guestfs_ldmtool_*" functions.

This function scans all block devices. To scan a subset of block devices, call "guestfs_ldmtool_scan_devices" instead.

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

This function depends on the feature "ldm". See also "guestfs_feature_available".

(Added in 1.20.0)

guestfs_ldmtool_scan_devices¶

 char **
 guestfs_ldmtool_scan_devices (guestfs_h *g,
                               char *const *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 "guestfs_ldmtool_*" functions.

The parameter "devices" is a list of block devices which are scanned. If this list is empty, all block devices are scanned.

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

This function depends on the feature "ldm". See also "guestfs_feature_available".

(Added in 1.20.0)

guestfs_ldmtool_volume_hint¶

 char *
 guestfs_ldmtool_volume_hint (guestfs_h *g,
                              const char *diskgroup,
                              const char *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:".

This function returns a string, or NULL on error. The caller must free the returned string after use.

This function depends on the feature "ldm". See also "guestfs_feature_available".

(Added in 1.20.0)

guestfs_ldmtool_volume_partitions¶

 char **
 guestfs_ldmtool_volume_partitions (guestfs_h *g,
                                    const char *diskgroup,
                                    const char *volume);

Return the list of partitions in the volume named "volume" in the disk group with GUID "diskgroup".

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

This function depends on the feature "ldm". See also "guestfs_feature_available".

(Added in 1.20.0)

guestfs_ldmtool_volume_type¶

 char *
 guestfs_ldmtool_volume_type (guestfs_h *g,
                              const char *diskgroup,
                              const char *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.

This function returns a string, or NULL on error. The caller must free the returned string after use.

This function depends on the feature "ldm". See also "guestfs_feature_available".

(Added in 1.20.0)

guestfs_lgetxattr¶

 char *
 guestfs_lgetxattr (guestfs_h *g,
                    const char *path,
                    const char *name,
                    size_t *size_r);

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 "guestfs_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: "guestfs_lgetxattrs", "guestfs_getxattr", attr(5).

This function returns a buffer, or NULL on error. The size of the returned buffer is written to *size_r. The caller must free the returned buffer after use.

This function depends on the feature "linuxxattrs". See also "guestfs_feature_available".

(Added in 1.7.24)

guestfs_lgetxattrs¶

 struct guestfs_xattr_list *
 guestfs_lgetxattrs (guestfs_h *g,
                     const char *path);

This is the same as "guestfs_getxattrs", but if "path" is a symbolic link, then it returns the extended attributes of the link itself.

This function returns a "struct guestfs_xattr_list *", or NULL if there was an error. The caller must call "guestfs_free_xattr_list" after use.

This function depends on the feature "linuxxattrs". See also "guestfs_feature_available".

(Added in 1.0.59)

guestfs_list_9p¶

 char **
 guestfs_list_9p (guestfs_h *g);

This function is deprecated. There is no replacement. Consult the API documentation in guestfs(3) for further information.

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.

This call does nothing and returns an error.

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

(Added in 1.11.12)

guestfs_list_devices¶

 char **
 guestfs_list_devices (guestfs_h *g);

List all the block devices.

The full block device names are returned, eg. /dev/sda.

See also "guestfs_list_filesystems".

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

(Added in 0.4)

guestfs_list_disk_labels¶

 char **
 guestfs_list_disk_labels (guestfs_h *g);

If you add drives using the optional "label" parameter of "guestfs_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).

This function returns a NULL-terminated array of strings, or NULL if there was an error. The array of strings will always have length "2n+1", where "n" keys and values alternate, followed by the trailing NULL entry. The caller must free the strings and the array after use.

(Added in 1.19.49)

guestfs_list_dm_devices¶

 char **
 guestfs_list_dm_devices (guestfs_h *g);

List all device mapper devices.

The returned list contains /dev/mapper/* devices, eg. ones created by a previous call to "guestfs_luks_open".

Device mapper devices which correspond to logical volumes are not returned in this list. Call "guestfs_lvs" if you want to list logical volumes.

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

(Added in 1.11.15)

guestfs_list_filesystems¶

 char **
 guestfs_list_filesystems (guestfs_h *g);

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 "guestfs_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.

In libguestfs ≤ 1.36 this command ran other libguestfs commands, which might have included "guestfs_mount" and "guestfs_umount", and therefore you had to use this soon after launch and only when nothing else was mounted. This restriction is removed in libguestfs ≥ 1.38.

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 "guestfs_inspect_os" to look for OSes).

This function returns a NULL-terminated array of strings, or NULL if there was an error. The array of strings will always have length "2n+1", where "n" keys and values alternate, followed by the trailing NULL entry. The caller must free the strings and the array after use.

(Added in 1.5.15)

guestfs_list_ldm_partitions¶

 char **
 guestfs_list_ldm_partitions (guestfs_h *g);

This function returns all Windows dynamic disk partitions that were found at launch time. It returns a list of device names.

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

This function depends on the feature "ldm". See also "guestfs_feature_available".

(Added in 1.20.0)

guestfs_list_ldm_volumes¶

 char **
 guestfs_list_ldm_volumes (guestfs_h *g);

This function returns all Windows dynamic disk volumes that were found at launch time. It returns a list of device names.

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

This function depends on the feature "ldm". See also "guestfs_feature_available".

(Added in 1.20.0)

guestfs_list_md_devices¶

 char **
 guestfs_list_md_devices (guestfs_h *g);

List all Linux md devices.

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

(Added in 1.15.4)

guestfs_list_partitions¶

 char **
 guestfs_list_partitions (guestfs_h *g);

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 "guestfs_lvs".

See also "guestfs_list_filesystems".

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

(Added in 0.4)

guestfs_ll¶

 char *
 guestfs_ll (guestfs_h *g,
             const char *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.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 0.4)

guestfs_llz¶

 char *
 guestfs_llz (guestfs_h *g,
              const char *directory);

This function is deprecated. In new code, use the "guestfs_lgetxattrs" 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.

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.

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.17.6)

guestfs_ln¶

 int
 guestfs_ln (guestfs_h *g,
             const char *target,
             const char *linkname);

This command creates a hard link.

This function returns 0 on success or -1 on error.

(Added in 1.0.66)

guestfs_ln_f¶

 int
 guestfs_ln_f (guestfs_h *g,
               const char *target,
               const char *linkname);

This command creates a hard link, removing the link "linkname" if it exists already.

This function returns 0 on success or -1 on error.

(Added in 1.0.66)

guestfs_ln_s¶

 int
 guestfs_ln_s (guestfs_h *g,
               const char *target,
               const char *linkname);

This command creates a symbolic link using the "ln -s" command.

This function returns 0 on success or -1 on error.

(Added in 1.0.66)

guestfs_ln_sf¶

 int
 guestfs_ln_sf (guestfs_h *g,
                const char *target,
                const char *linkname);

This command creates a symbolic link using the "ln -sf" command, The -f option removes the link ("linkname") if it exists already.

This function returns 0 on success or -1 on error.

(Added in 1.0.66)

guestfs_lremovexattr¶

 int
 guestfs_lremovexattr (guestfs_h *g,
                       const char *xattr,
                       const char *path);

This is the same as "guestfs_removexattr", but if "path" is a symbolic link, then it removes an extended attribute of the link itself.

This function returns 0 on success or -1 on error.

This function depends on the feature "linuxxattrs". See also "guestfs_feature_available".

(Added in 1.0.59)

guestfs_ls¶

 char **
 guestfs_ls (guestfs_h *g,
             const char *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.

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

(Added in 0.4)

guestfs_ls0¶

 int
 guestfs_ls0 (guestfs_h *g,
              const char *dir,
              const char *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.

This function returns 0 on success or -1 on error.

(Added in 1.19.32)

guestfs_lsetxattr¶

 int
 guestfs_lsetxattr (guestfs_h *g,
                    const char *xattr,
                    const char *val,
                    int vallen,
                    const char *path);

This is the same as "guestfs_setxattr", but if "path" is a symbolic link, then it sets an extended attribute of the link itself.

This function returns 0 on success or -1 on error.

This function depends on the feature "linuxxattrs". See also "guestfs_feature_available".

(Added in 1.0.59)

guestfs_lstat¶

 struct guestfs_stat *
 guestfs_lstat (guestfs_h *g,
                const char *path);

This function is deprecated. In new code, use the "guestfs_lstatns" 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.

Returns file information for the given "path".

This is the same as "guestfs_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.

This function returns a "struct guestfs_stat *", or NULL if there was an error. The caller must call "guestfs_free_stat" after use.

(Added in 1.9.2)

guestfs_lstatlist¶

 struct guestfs_stat_list *
 guestfs_lstatlist (guestfs_h *g,
                    const char *path,
                    char *const *names);

This function is deprecated. In new code, use the "guestfs_lstatnslist" 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.

This call allows you to perform the "guestfs_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 "st_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 "guestfs_lxattrlist" for a similarly efficient call for getting extended attributes.

This function returns a "struct guestfs_stat_list *", or NULL if there was an error. The caller must call "guestfs_free_stat_list" after use.

(Added in 1.0.77)

guestfs_lstatns¶

 struct guestfs_statns *
 guestfs_lstatns (guestfs_h *g,
                  const char *path);

Returns file information for the given "path".

This is the same as "guestfs_statns" 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.

This function returns a "struct guestfs_statns *", or NULL if there was an error. The caller must call "guestfs_free_statns" after use.

(Added in 1.27.53)

guestfs_lstatnslist¶

 struct guestfs_statns_list *
 guestfs_lstatnslist (guestfs_h *g,
                      const char *path,
                      char *const *names);

This call allows you to perform the "guestfs_lstatns" 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 "st_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 "guestfs_lxattrlist" for a similarly efficient call for getting extended attributes.

This function returns a "struct guestfs_statns_list *", or NULL if there was an error. The caller must call "guestfs_free_statns_list" after use.

(Added in 1.27.53)

guestfs_luks_add_key¶

 int
 guestfs_luks_add_key (guestfs_h *g,
                       const char *device,
                       const char *key,
                       const char *newkey,
                       int 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 "guestfs_luks_kill_slot" first to remove that key.

This function returns 0 on success or -1 on error.

This function takes a key or passphrase parameter which could contain sensitive material. Read the section "KEYS AND PASSPHRASES" for more information.

This function depends on the feature "luks". See also "guestfs_feature_available".

(Added in 1.5.2)

guestfs_luks_close¶

 int
 guestfs_luks_close (guestfs_h *g,
                     const char *device);

This function is deprecated. In new code, use the "guestfs_cryptsetup_close" 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.

This closes a LUKS device that was created earlier by "guestfs_luks_open" or "guestfs_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.

This function returns 0 on success or -1 on error.

This function depends on the feature "luks". See also "guestfs_feature_available".

(Added in 1.5.1)

guestfs_luks_format¶

 int
 guestfs_luks_format (guestfs_h *g,
                      const char *device,
                      const char *key,
                      int 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 "keyslot". (LUKS supports 8 key slots, numbered 0-7).

This function returns 0 on success or -1 on error.

This function takes a key or passphrase parameter which could contain sensitive material. Read the section "KEYS AND PASSPHRASES" for more information.

This function depends on the feature "luks". See also "guestfs_feature_available".

(Added in 1.5.2)

guestfs_luks_format_cipher¶

 int
 guestfs_luks_format_cipher (guestfs_h *g,
                             const char *device,
                             const char *key,
                             int keyslot,
                             const char *cipher);

This command is the same as "guestfs_luks_format" but it also allows you to set the "cipher" used.

This function returns 0 on success or -1 on error.

This function takes a key or passphrase parameter which could contain sensitive material. Read the section "KEYS AND PASSPHRASES" for more information.

This function depends on the feature "luks". See also "guestfs_feature_available".

(Added in 1.5.2)

guestfs_luks_kill_slot¶

 int
 guestfs_luks_kill_slot (guestfs_h *g,
                         const char *device,
                         const char *key,
                         int keyslot);

This command deletes the key in key slot "keyslot" from the encrypted LUKS device "device". "key" must be one of the other keys.

This function returns 0 on success or -1 on error.

This function takes a key or passphrase parameter which could contain sensitive material. Read the section "KEYS AND PASSPHRASES" for more information.

This function depends on the feature "luks". See also "guestfs_feature_available".

(Added in 1.5.2)

guestfs_luks_open¶

 int
 guestfs_luks_open (guestfs_h *g,
                    const char *device,
                    const char *key,
                    const char *mapname);

This function is deprecated. In new code, use the "guestfs_cryptsetup_open" 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.

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 "guestfs_lvm_scan" with the "activate" parameter "true" will make them visible.

Use "guestfs_list_dm_devices" to list all device mapper devices.

This function returns 0 on success or -1 on error.

This function takes a key or passphrase parameter which could contain sensitive material. Read the section "KEYS AND PASSPHRASES" for more information.

This function depends on the feature "luks". See also "guestfs_feature_available".

(Added in 1.5.1)

guestfs_luks_open_ro¶

 int
 guestfs_luks_open_ro (guestfs_h *g,
                       const char *device,
                       const char *key,
                       const char *mapname);

This function is deprecated. In new code, use the "guestfs_cryptsetup_open" 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.

This is the same as "guestfs_luks_open" except that a read-only mapping is created.

This function returns 0 on success or -1 on error.

This function takes a key or passphrase parameter which could contain sensitive material. Read the section "KEYS AND PASSPHRASES" for more information.

This function depends on the feature "luks". See also "guestfs_feature_available".

(Added in 1.5.1)

guestfs_luks_uuid¶

 char *
 guestfs_luks_uuid (guestfs_h *g,
                    const char *device);

This returns the UUID of the LUKS device "device".

This function returns a string, or NULL on error. The caller must free the returned string after use.

This function depends on the feature "luks". See also "guestfs_feature_available".

(Added in 1.41.9)

guestfs_lvcreate¶

 int
 guestfs_lvcreate (guestfs_h *g,
                   const char *logvol,
                   const char *volgroup,
                   int mbytes);

This creates an LVM logical volume called "logvol" on the volume group "volgroup", with "size" megabytes.

This function returns 0 on success or -1 on error.

This function depends on the feature "lvm2". See also "guestfs_feature_available".

(Added in 0.8)

guestfs_lvcreate_free¶

 int
 guestfs_lvcreate_free (guestfs_h *g,
                        const char *logvol,
                        const char *volgroup,
                        int 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.

This function returns 0 on success or -1 on error.

This function depends on the feature "lvm2". See also "guestfs_feature_available".

(Added in 1.17.18)

guestfs_lvm_canonical_lv_name¶

 char *
 guestfs_lvm_canonical_lv_name (guestfs_h *g,
                                const char *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. In this case errno will be set to "EINVAL".

See also "guestfs_is_lv", "guestfs_canonical_device_name".

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.5.24)

guestfs_lvm_clear_filter¶

 int
 guestfs_lvm_clear_filter (guestfs_h *g);

This undoes the effect of "guestfs_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.

This function returns 0 on success or -1 on error.

(Added in 1.5.1)

guestfs_lvm_remove_all¶

 int
 guestfs_lvm_remove_all (guestfs_h *g);

This command removes all LVM logical volumes, volume groups and physical volumes.

This function returns 0 on success or -1 on error.

This function depends on the feature "lvm2". See also "guestfs_feature_available".

(Added in 0.8)

guestfs_lvm_scan¶

 int
 guestfs_lvm_scan (guestfs_h *g,
                   int activate);

This scans all block devices and rebuilds the list of LVM physical volumes, volume groups and logical volumes.

If the "activate" parameter is "true" then newly found volume groups and logical volumes are activated, meaning the LV /dev/VG/LV devices become visible.

When a libguestfs handle is launched it scans for existing devices, so you do not normally need to use this API. However it is useful when you have added a new device or deleted an existing device (such as when the "guestfs_luks_open" API is used).

This function returns 0 on success or -1 on error.

(Added in 1.39.8)

guestfs_lvm_set_filter¶

 int
 guestfs_lvm_set_filter (guestfs_h *g,
                         char *const *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.

This function returns 0 on success or -1 on error.

This function depends on the feature "lvm2". See also "guestfs_feature_available".

(Added in 1.5.1)

guestfs_lvremove¶

 int
 guestfs_lvremove (guestfs_h *g,
                   const char *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.

This function returns 0 on success or -1 on error.

This function depends on the feature "lvm2". See also "guestfs_feature_available".

(Added in 1.0.13)

guestfs_lvrename¶

 int
 guestfs_lvrename (guestfs_h *g,
                   const char *logvol,
                   const char *newlogvol);

Rename a logical volume "logvol" with the new name "newlogvol".

This function returns 0 on success or -1 on error.

(Added in 1.0.83)

guestfs_lvresize¶

 int
 guestfs_lvresize (guestfs_h *g,
                   const char *device,
                   int mbytes);

This resizes (expands or shrinks) an existing LVM logical volume to "mbytes". When reducing, data in the reduced part is lost.

This function returns 0 on success or -1 on error.

This function depends on the feature "lvm2". See also "guestfs_feature_available".

(Added in 1.0.27)

guestfs_lvresize_free¶

 int
 guestfs_lvresize_free (guestfs_h *g,
                        const char *lv,
                        int 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.

This function returns 0 on success or -1 on error.

This function depends on the feature "lvm2". See also "guestfs_feature_available".

(Added in 1.3.3)

guestfs_lvs¶

 char **
 guestfs_lvs (guestfs_h *g);

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 "guestfs_lvs_full", "guestfs_list_filesystems".

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

This function depends on the feature "lvm2". See also "guestfs_feature_available".

(Added in 0.4)

guestfs_lvs_full¶

 struct guestfs_lvm_lv_list *
 guestfs_lvs_full (guestfs_h *g);

List all the logical volumes detected. This is the equivalent of the lvs(8) command. The "full" version includes all fields.

This function returns a "struct guestfs_lvm_lv_list *", or NULL if there was an error. The caller must call "guestfs_free_lvm_lv_list" after use.

This function depends on the feature "lvm2". See also "guestfs_feature_available".

(Added in 0.4)

guestfs_lvuuid¶

 char *
 guestfs_lvuuid (guestfs_h *g,
                 const char *device);

This command returns the UUID of the LVM LV "device".

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.0.87)

guestfs_lxattrlist¶

 struct guestfs_xattr_list *
 guestfs_lxattrlist (guestfs_h *g,
                     const char *path,
                     char *const *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 "guestfs_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 "guestfs_lstatlist" for a similarly efficient call for getting standard stats.

This function returns a "struct guestfs_xattr_list *", or NULL if there was an error. The caller must call "guestfs_free_xattr_list" after use.

This function depends on the feature "linuxxattrs". See also "guestfs_feature_available".

(Added in 1.0.77)

guestfs_max_disks¶

 int
 guestfs_max_disks (guestfs_h *g);

Return the maximum number of disks that may be added to a handle (eg. by "guestfs_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" for additional information on this topic.

On error this function returns -1.

(Added in 1.19.7)

guestfs_md_create¶

 int
 guestfs_md_create (guestfs_h *g,
                    const char *name,
                    char *const *devices,
                    ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_MD_CREATE_MISSINGBITMAP, int64_t missingbitmap,
 GUESTFS_MD_CREATE_NRDEVICES, int nrdevices,
 GUESTFS_MD_CREATE_SPARE, int spare,
 GUESTFS_MD_CREATE_CHUNK, int64_t chunk,
 GUESTFS_MD_CREATE_LEVEL, const char *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.

The "chunk" parameter does not make sense, and should not be specified, when "level" is "raid1" (which is the default; see below).

"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".

This function returns 0 on success or -1 on error.

This function depends on the feature "mdadm". See also "guestfs_feature_available".

(Added in 1.15.6)

guestfs_md_create_va¶

 int
 guestfs_md_create_va (guestfs_h *g,
                       const char *name,
                       char *const *devices,
                       va_list args);

This is the "va_list variant" of "guestfs_md_create".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_md_create_argv¶

 int
 guestfs_md_create_argv (guestfs_h *g,
                         const char *name,
                         char *const *devices,
                         const struct guestfs_md_create_argv *optargs);

This is the "argv variant" of "guestfs_md_create".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_md_detail¶

 char **
 guestfs_md_detail (guestfs_h *g,
                    const char *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.

This function returns a NULL-terminated array of strings, or NULL if there was an error. The array of strings will always have length "2n+1", where "n" keys and values alternate, followed by the trailing NULL entry. The caller must free the strings and the array after use.

This function depends on the feature "mdadm". See also "guestfs_feature_available".

(Added in 1.15.6)

guestfs_md_stat¶

 struct guestfs_mdstat_list *
 guestfs_md_stat (guestfs_h *g,
                  const char *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 "guestfs_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:

This function returns a "struct guestfs_mdstat_list *", or NULL if there was an error. The caller must call "guestfs_free_mdstat_list" after use.

This function depends on the feature "mdadm". See also "guestfs_feature_available".

(Added in 1.17.21)

guestfs_md_stop¶

 int
 guestfs_md_stop (guestfs_h *g,
                  const char *md);

This command deactivates the MD array named "md". The device is stopped, but it is not destroyed or zeroed.

This function returns 0 on success or -1 on error.

This function depends on the feature "mdadm". See also "guestfs_feature_available".

(Added in 1.15.6)

guestfs_mkdir¶

 int
 guestfs_mkdir (guestfs_h *g,
                const char *path);

Create a directory named "path".

This function returns 0 on success or -1 on error.

(Added in 0.8)

guestfs_mkdir_mode¶

 int
 guestfs_mkdir_mode (guestfs_h *g,
                     const char *path,
                     int 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 "guestfs_mkdir", "guestfs_umask"

This function returns 0 on success or -1 on error.

(Added in 1.0.77)

guestfs_mkdir_p¶

 int
 guestfs_mkdir_p (guestfs_h *g,
                  const char *path);

Create a directory named "path", creating any parent directories as necessary. This is like the "mkdir -p" shell command.

This function returns 0 on success or -1 on error.

(Added in 0.8)

guestfs_mkdtemp¶

 char *
 guestfs_mkdtemp (guestfs_h *g,
                  const char *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)

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.0.54)

guestfs_mke2fs¶

 int
 guestfs_mke2fs (guestfs_h *g,
                 const char *device,
                 ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_MKE2FS_BLOCKSCOUNT, int64_t blockscount,
 GUESTFS_MKE2FS_BLOCKSIZE, int64_t blocksize,
 GUESTFS_MKE2FS_FRAGSIZE, int64_t fragsize,
 GUESTFS_MKE2FS_BLOCKSPERGROUP, int64_t blockspergroup,
 GUESTFS_MKE2FS_NUMBEROFGROUPS, int64_t numberofgroups,
 GUESTFS_MKE2FS_BYTESPERINODE, int64_t bytesperinode,
 GUESTFS_MKE2FS_INODESIZE, int64_t inodesize,
 GUESTFS_MKE2FS_JOURNALSIZE, int64_t journalsize,
 GUESTFS_MKE2FS_NUMBEROFINODES, int64_t numberofinodes,
 GUESTFS_MKE2FS_STRIDESIZE, int64_t stridesize,
 GUESTFS_MKE2FS_STRIPEWIDTH, int64_t stripewidth,
 GUESTFS_MKE2FS_MAXONLINERESIZE, int64_t maxonlineresize,
 GUESTFS_MKE2FS_RESERVEDBLOCKSPERCENTAGE, int reservedblockspercentage,
 GUESTFS_MKE2FS_MMPUPDATEINTERVAL, int mmpupdateinterval,
 GUESTFS_MKE2FS_JOURNALDEVICE, const char *journaldevice,
 GUESTFS_MKE2FS_LABEL, const char *label,
 GUESTFS_MKE2FS_LASTMOUNTEDDIR, const char *lastmounteddir,
 GUESTFS_MKE2FS_CREATOROS, const char *creatoros,
 GUESTFS_MKE2FS_FSTYPE, const char *fstype,
 GUESTFS_MKE2FS_USAGETYPE, const char *usagetype,
 GUESTFS_MKE2FS_UUID, const char *uuid,
 GUESTFS_MKE2FS_FORCECREATE, int forcecreate,
 GUESTFS_MKE2FS_WRITESBANDGROUPONLY, int writesbandgrouponly,
 GUESTFS_MKE2FS_LAZYITABLEINIT, int lazyitableinit,
 GUESTFS_MKE2FS_LAZYJOURNALINIT, int lazyjournalinit,
 GUESTFS_MKE2FS_TESTFS, int testfs,
 GUESTFS_MKE2FS_DISCARD, int discard,
 GUESTFS_MKE2FS_QUOTATYPE, int quotatype,
 GUESTFS_MKE2FS_EXTENT, int extent,
 GUESTFS_MKE2FS_FILETYPE, int filetype,
 GUESTFS_MKE2FS_FLEXBG, int flexbg,
 GUESTFS_MKE2FS_HASJOURNAL, int hasjournal,
 GUESTFS_MKE2FS_JOURNALDEV, int journaldev,
 GUESTFS_MKE2FS_LARGEFILE, int largefile,
 GUESTFS_MKE2FS_QUOTA, int quota,
 GUESTFS_MKE2FS_RESIZEINODE, int resizeinode,
 GUESTFS_MKE2FS_SPARSESUPER, int sparsesuper,
 GUESTFS_MKE2FS_UNINITBG, int 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.

This function returns 0 on success or -1 on error.

(Added in 1.19.44)

guestfs_mke2fs_va¶

 int
 guestfs_mke2fs_va (guestfs_h *g,
                    const char *device,
                    va_list args);

This is the "va_list variant" of "guestfs_mke2fs".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_mke2fs_argv¶

 int
 guestfs_mke2fs_argv (guestfs_h *g,
                      const char *device,
                      const struct guestfs_mke2fs_argv *optargs);

This is the "argv variant" of "guestfs_mke2fs".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_mke2fs_J¶

 int
 guestfs_mke2fs_J (guestfs_h *g,
                   const char *fstype,
                   int blocksize,
                   const char *device,
                   const char *journal);

This function is deprecated. In new code, use the "guestfs_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.

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 "guestfs_mke2journal".

This function returns 0 on success or -1 on error.

(Added in 1.0.68)

guestfs_mke2fs_JL¶

 int
 guestfs_mke2fs_JL (guestfs_h *g,
                    const char *fstype,
                    int blocksize,
                    const char *device,
                    const char *label);

This function is deprecated. In new code, use the "guestfs_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.

This creates an ext2/3/4 filesystem on "device" with an external journal on the journal labeled "label".

See also "guestfs_mke2journal_L".

This function returns 0 on success or -1 on error.

(Added in 1.0.68)

guestfs_mke2fs_JU¶

 int
 guestfs_mke2fs_JU (guestfs_h *g,
                    const char *fstype,
                    int blocksize,
                    const char *device,
                    const char *uuid);

This function is deprecated. In new code, use the "guestfs_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.

This creates an ext2/3/4 filesystem on "device" with an external journal on the journal with UUID "uuid".

See also "guestfs_mke2journal_U".

This function returns 0 on success or -1 on error.

This function depends on the feature "linuxfsuuid". See also "guestfs_feature_available".

(Added in 1.0.68)

guestfs_mke2journal¶

 int
 guestfs_mke2journal (guestfs_h *g,
                      int blocksize,
                      const char *device);

This function is deprecated. In new code, use the "guestfs_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.

This creates an ext2 external journal on "device". It is equivalent to the command:

 mke2fs -O journal_dev -b blocksize device

This function returns 0 on success or -1 on error.

(Added in 1.0.68)

guestfs_mke2journal_L¶

 int
 guestfs_mke2journal_L (guestfs_h *g,
                        int blocksize,
                        const char *label,
                        const char *device);

This function is deprecated. In new code, use the "guestfs_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.

This creates an ext2 external journal on "device" with label "label".

This function returns 0 on success or -1 on error.

(Added in 1.0.68)

guestfs_mke2journal_U¶

 int
 guestfs_mke2journal_U (guestfs_h *g,
                        int blocksize,
                        const char *uuid,
                        const char *device);

This function is deprecated. In new code, use the "guestfs_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.

This creates an ext2 external journal on "device" with UUID "uuid".

This function returns 0 on success or -1 on error.

This function depends on the feature "linuxfsuuid". See also "guestfs_feature_available".

(Added in 1.0.68)

guestfs_mkfifo¶

 int
 guestfs_mkfifo (guestfs_h *g,
                 int mode,
                 const char *path);

This call creates a FIFO (named pipe) called "path" with mode "mode". It is just a convenient wrapper around "guestfs_mknod".

Unlike with "guestfs_mknod", "mode" must contain only permissions bits.

The mode actually set is affected by the umask.

This function returns 0 on success or -1 on error.

This function depends on the feature "mknod". See also "guestfs_feature_available".

(Added in 1.0.55)

guestfs_mkfs¶

 int
 guestfs_mkfs (guestfs_h *g,
               const char *fstype,
               const char *device);

This function is provided for backwards compatibility with earlier versions of libguestfs. It simply calls "guestfs_mkfs_opts" with no optional arguments.

(Added in 0.8)

guestfs_mkfs_opts¶

 int
 guestfs_mkfs_opts (guestfs_h *g,
                    const char *fstype,
                    const char *device,
                    ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_MKFS_OPTS_BLOCKSIZE, int blocksize,
 GUESTFS_MKFS_OPTS_FEATURES, const char *features,
 GUESTFS_MKFS_OPTS_INODE, int inode,
 GUESTFS_MKFS_OPTS_SECTORSIZE, int sectorsize,
 GUESTFS_MKFS_OPTS_LABEL, const char *label,

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.

This function returns 0 on success or -1 on error.

(Added in 0.8)

guestfs_mkfs_opts_va¶

 int
 guestfs_mkfs_opts_va (guestfs_h *g,
                       const char *fstype,
                       const char *device,
                       va_list args);

This is the "va_list variant" of "guestfs_mkfs_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_mkfs_opts_argv¶

 int
 guestfs_mkfs_opts_argv (guestfs_h *g,
                         const char *fstype,
                         const char *device,
                         const struct guestfs_mkfs_opts_argv *optargs);

This is the "argv variant" of "guestfs_mkfs_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_mkfs_b¶

 int
 guestfs_mkfs_b (guestfs_h *g,
                 const char *fstype,
                 int blocksize,
                 const char *device);

This function is deprecated. In new code, use the "guestfs_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.

This call is similar to "guestfs_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 returns 0 on success or -1 on error.

(Added in 1.0.68)

guestfs_mkfs_btrfs¶

 int
 guestfs_mkfs_btrfs (guestfs_h *g,
                     char *const *devices,
                     ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_MKFS_BTRFS_ALLOCSTART, int64_t allocstart,
 GUESTFS_MKFS_BTRFS_BYTECOUNT, int64_t bytecount,
 GUESTFS_MKFS_BTRFS_DATATYPE, const char *datatype,
 GUESTFS_MKFS_BTRFS_LEAFSIZE, int leafsize,
 GUESTFS_MKFS_BTRFS_LABEL, const char *label,
 GUESTFS_MKFS_BTRFS_METADATA, const char *metadata,
 GUESTFS_MKFS_BTRFS_NODESIZE, int nodesize,
 GUESTFS_MKFS_BTRFS_SECTORSIZE, int 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 "guestfs_mkfs".

This function returns 0 on success or -1 on error.

This function depends on the feature "btrfs". See also "guestfs_feature_available".

(Added in 1.17.25)

guestfs_mkfs_btrfs_va¶

 int
 guestfs_mkfs_btrfs_va (guestfs_h *g,
                        char *const *devices,
                        va_list args);

This is the "va_list variant" of "guestfs_mkfs_btrfs".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_mkfs_btrfs_argv¶

 int
 guestfs_mkfs_btrfs_argv (guestfs_h *g,
                          char *const *devices,
                          const struct guestfs_mkfs_btrfs_argv *optargs);

This is the "argv variant" of "guestfs_mkfs_btrfs".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_mklost_and_found¶

 int
 guestfs_mklost_and_found (guestfs_h *g,
                           const char *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.

This function returns 0 on success or -1 on error.

(Added in 1.19.56)

guestfs_mkmountpoint¶

 int
 guestfs_mkmountpoint (guestfs_h *g,
                       const char *exemptpath);

"guestfs_mkmountpoint" and "guestfs_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.

"guestfs_mkmountpoint" is not compatible with "guestfs_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.

"guestfs_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 "guestfs_set_autosync", this is set by default on handles] can cause "guestfs_umount_all" to be called when the handle is closed which can also trigger these issues.

This function returns 0 on success or -1 on error.

(Added in 1.0.62)

guestfs_mknod¶

 int
 guestfs_mknod (guestfs_h *g,
                int mode,
                int devmajor,
                int devminor,
                const char *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 "guestfs_mknod_b", "guestfs_mknod_c" or "guestfs_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.

This function returns 0 on success or -1 on error.

This function depends on the feature "mknod". See also "guestfs_feature_available".

(Added in 1.0.55)

guestfs_mknod_b¶

 int
 guestfs_mknod_b (guestfs_h *g,
                  int mode,
                  int devmajor,
                  int devminor,
                  const char *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 "guestfs_mknod".

Unlike with "guestfs_mknod", "mode" must contain only permissions bits.

The mode actually set is affected by the umask.

This function returns 0 on success or -1 on error.

This function depends on the feature "mknod". See also "guestfs_feature_available".

(Added in 1.0.55)

guestfs_mknod_c¶

 int
 guestfs_mknod_c (guestfs_h *g,
                  int mode,
                  int devmajor,
                  int devminor,
                  const char *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 "guestfs_mknod".

Unlike with "guestfs_mknod", "mode" must contain only permissions bits.

The mode actually set is affected by the umask.

This function returns 0 on success or -1 on error.

This function depends on the feature "mknod". See also "guestfs_feature_available".

(Added in 1.0.55)

guestfs_mksquashfs¶

 int
 guestfs_mksquashfs (guestfs_h *g,
                     const char *path,
                     const char *filename,
                     ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_MKSQUASHFS_COMPRESS, const char *compress,
 GUESTFS_MKSQUASHFS_EXCLUDES, char *const *excludes,

Create a squashfs filesystem for the specified "path".

The optional "compress" flag controls compression. If not given, then the output compressed using "gzip". Otherwise one of the following strings may be given to select the compression type of the squashfs: "gzip", "lzma", "lzo", "lz4", "xz".

The other optional arguments are:

"excludes"

A list of wildcards. Files are excluded if they match any of the wildcards.

Please note that this API may fail when used to compress directories with large files, such as the resulting squashfs will be over 3GB big.

This function returns 0 on success or -1 on error.

This function depends on the feature "squashfs". See also "guestfs_feature_available".

(Added in 1.35.25)

guestfs_mksquashfs_va¶

 int
 guestfs_mksquashfs_va (guestfs_h *g,
                        const char *path,
                        const char *filename,
                        va_list args);

This is the "va_list variant" of "guestfs_mksquashfs".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_mksquashfs_argv¶

 int
 guestfs_mksquashfs_argv (guestfs_h *g,
                          const char *path,
                          const char *filename,
                          const struct guestfs_mksquashfs_argv *optargs);

This is the "argv variant" of "guestfs_mksquashfs".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_mkswap¶

 int
 guestfs_mkswap (guestfs_h *g,
                 const char *device);

This function is provided for backwards compatibility with earlier versions of libguestfs. It simply calls "guestfs_mkswap_opts" with no optional arguments.

(Added in 1.0.55)

guestfs_mkswap_opts¶

 int
 guestfs_mkswap_opts (guestfs_h *g,
                      const char *device,
                      ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_MKSWAP_OPTS_LABEL, const char *label,
 GUESTFS_MKSWAP_OPTS_UUID, const char *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.

This function returns 0 on success or -1 on error.

(Added in 1.0.55)

guestfs_mkswap_opts_va¶

 int
 guestfs_mkswap_opts_va (guestfs_h *g,
                         const char *device,
                         va_list args);

This is the "va_list variant" of "guestfs_mkswap_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_mkswap_opts_argv¶

 int
 guestfs_mkswap_opts_argv (guestfs_h *g,
                           const char *device,
                           const struct guestfs_mkswap_opts_argv *optargs);

This is the "argv variant" of "guestfs_mkswap_opts".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_mkswap_L¶

 int
 guestfs_mkswap_L (guestfs_h *g,
                   const char *label,
                   const char *device);

This function is deprecated. In new code, use the "guestfs_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.

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 returns 0 on success or -1 on error.

(Added in 1.0.55)

guestfs_mkswap_U¶

 int
 guestfs_mkswap_U (guestfs_h *g,
                   const char *uuid,
                   const char *device);

This function is deprecated. In new code, use the "guestfs_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.

Create a swap partition on "device" with UUID "uuid".

This function returns 0 on success or -1 on error.

This function depends on the feature "linuxfsuuid". See also "guestfs_feature_available".

(Added in 1.0.55)

guestfs_mkswap_file¶

 int
 guestfs_mkswap_file (guestfs_h *g,
                      const char *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 "guestfs_fallocate".

This function returns 0 on success or -1 on error.

(Added in 1.0.66)

guestfs_mktemp¶

 char *
 guestfs_mktemp (guestfs_h *g,
                 const char *tmpl,
                 ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_MKTEMP_SUFFIX, const char *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: "guestfs_mkdtemp".

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.19.53)

guestfs_mktemp_va¶

 char *
 guestfs_mktemp_va (guestfs_h *g,
                    const char *tmpl,
                    va_list args);

This is the "va_list variant" of "guestfs_mktemp".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_mktemp_argv¶

 char *
 guestfs_mktemp_argv (guestfs_h *g,
                      const char *tmpl,
                      const struct guestfs_mktemp_argv *optargs);

This is the "argv variant" of "guestfs_mktemp".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_modprobe¶

 int
 guestfs_modprobe (guestfs_h *g,
                   const char *modulename);

This loads a kernel module in the appliance.

This function returns 0 on success or -1 on error.

This function depends on the feature "linuxmodules". See also "guestfs_feature_available".

(Added in 1.0.68)

guestfs_mount¶

 int
 guestfs_mount (guestfs_h *g,
                const char *mountable,
                const char *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 "guestfs_list_filesystems" or "guestfs_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 "guestfs_mount_options" instead (using an empty string for the first parameter if you don't want any options).

This function returns 0 on success or -1 on error.

(Added in 0.3)

guestfs_mount_9p¶

 int
 guestfs_mount_9p (guestfs_h *g,
                   const char *mounttag,
                   const char *mountpoint,
                   ...);

This function is deprecated. There is no replacement. Consult the API documentation in guestfs(3) for further information.

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.

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_MOUNT_9P_OPTIONS, const char *options,

This call does nothing and returns an error.

This function returns 0 on success or -1 on error.

(Added in 1.11.12)

guestfs_mount_9p_va¶

 int
 guestfs_mount_9p_va (guestfs_h *g,
                      const char *mounttag,
                      const char *mountpoint,
                      va_list args);

This is the "va_list variant" of "guestfs_mount_9p".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_mount_9p_argv¶

 int
 guestfs_mount_9p_argv (guestfs_h *g,
                        const char *mounttag,
                        const char *mountpoint,
                        const struct guestfs_mount_9p_argv *optargs);

This is the "argv variant" of "guestfs_mount_9p".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_mount_local¶

 int
 guestfs_mount_local (guestfs_h *g,
                      const char *localmountpoint,
                      ...);

You may supply a list of optional arguments to this call. Use zero or more of the following pairs of parameters, and terminate the list with -1 on its own. See "CALLS WITH OPTIONAL ARGUMENTS".

 GUESTFS_MOUNT_LOCAL_READONLY, int readonly,
 GUESTFS_MOUNT_LOCAL_OPTIONS, const char *options,
 GUESTFS_MOUNT_LOCAL_CACHETIMEOUT, int cachetimeout,
 GUESTFS_MOUNT_LOCAL_DEBUGCALLS, int 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 "guestfs_mount_local" returns, the filesystem is ready, but is not processing requests (access to it will block). You have to call "guestfs_mount_local_run" to run the main loop.

See "MOUNT LOCAL" for full documentation.

This function returns 0 on success or -1 on error.

(Added in 1.17.22)

guestfs_mount_local_va¶

 int
 guestfs_mount_local_va (guestfs_h *g,
                         const char *localmountpoint,
                         va_list args);

This is the "va_list variant" of "guestfs_mount_local".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_mount_local_argv¶

 int
 guestfs_mount_local_argv (guestfs_h *g,
                           const char *localmountpoint,
                           const struct guestfs_mount_local_argv *optargs);

This is the "argv variant" of "guestfs_mount_local".

See "CALLS WITH OPTIONAL ARGUMENTS".

guestfs_mount_local_run¶

 int
 guestfs_mount_local_run (guestfs_h *g);

Run the main loop which translates kernel calls to libguestfs calls.

This should only be called after "guestfs_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 "guestfs_mount_local", subject to the usual rules for threads and libguestfs (see "MULTIPLE HANDLES AND MULTIPLE THREADS").

See "MOUNT LOCAL" for full documentation.

This function returns 0 on success or -1 on error.

(Added in 1.17.22)

guestfs_mount_loop¶

 int
 guestfs_mount_loop (guestfs_h *g,
                     const char *file,
                     const char *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".

This function returns 0 on success or -1 on error.

(Added in 1.0.54)

guestfs_mount_options¶

 int
 guestfs_mount_options (guestfs_h *g,
                        const char *options,
                        const char *mountable,
                        const char *mountpoint);

This is the same as the "guestfs_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).

This function returns 0 on success or -1 on error.

(Added in 1.0.10)

guestfs_mount_ro¶

 int
 guestfs_mount_ro (guestfs_h *g,
                   const char *mountable,
                   const char *mountpoint);

This is the same as the "guestfs_mount" command, but it mounts the filesystem with the read-only (-o ro) flag.

This function returns 0 on success or -1 on error.

(Added in 1.0.10)

guestfs_mount_vfs¶

 int
 guestfs_mount_vfs (guestfs_h *g,
                    const char *options,
                    const char *vfstype,
                    const char *mountable,
                    const char *mountpoint);

This is the same as the "guestfs_mount" command, but it allows you to set both the mount options and the vfstype as for the mount(8) -o and -t flags.

This function returns 0 on success or -1 on error.

(Added in 1.0.10)

guestfs_mountable_device¶

 char *
 guestfs_mountable_device (guestfs_h *g,
                           const char *mountable);

Returns the device name of a mountable. In quite a lot of cases, the mountable is the device name.

However this doesn't apply for btrfs subvolumes, where the mountable is a combination of both the device name and the subvolume path (see also "guestfs_mountable_subvolume" to extract the subvolume path of the mountable if any).

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.33.15)

guestfs_mountable_subvolume¶

 char *
 guestfs_mountable_subvolume (guestfs_h *g,
                              const char *mountable);

Returns the subvolume path of a mountable. Btrfs subvolumes mountables are a combination of both the device name and the subvolume path (see also "guestfs_mountable_device" to extract the device of the mountable).

If the mountable does not represent a btrfs subvolume, then this function fails and the "errno" is set to "EINVAL".

This function returns a string, or NULL on error. The caller must free the returned string after use.

(Added in 1.33.15)

guestfs_mountpoints¶

 char **
 guestfs_mountpoints (guestfs_h *g);

This call is similar to "guestfs_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.

This function returns a NULL-terminated array of strings, or NULL if there was an error. The array of strings will always have length "2n+1", where "n" keys and values alternate, followed by the trailing NULL entry. The caller must free the strings and the array after use.

(Added in 1.0.62)

guestfs_mounts¶

 char **
 guestfs_mounts (guestfs_h *g);

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: "guestfs_mountpoints"

This function returns a NULL-terminated array of strings (like environ(3)), or NULL if there was an error. The caller must free the strings and the array after use.

(Added in 0.8)

guestfs_mv¶

 int
 guestfs_mv (guestfs_h *g,
             const char *src,
             const char *dest);

This moves a file from "src" to "dest" where "dest" is either a destination filename or destination directory.

See also: "guestfs_rename".

This function returns 0 on success or -1 on error.

(Added in 1.0.18)

guestfs_nr_devices¶

 int
 guestfs_nr_devices (guestfs_h *g);

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 "guestfs_list_devices".

To find out the maximum number of devices that could be added, call "guestfs_max_disks".

On error this function returns -1.

(Added in 1.19.15)

guestfs_ntfs_3g_probe¶

 int
 guestfs_ntfs_3g_probe (guestfs_h *g,
                        int rw,
                        const char *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.

On error this function returns -1.

This function depends on the feature "ntfs3g". See also "guestfs_feature_available".

(Added in 1.0.43)

guestfs_ntfscat_i¶

 int
 guestfs_ntfscat_i (guestfs_h *g,
                    const char *device,
                    int64_t inode,
                    const char *filename);

Download a file given its inode from a NTFS filesystem and save it as filename on the local machine.

This allows to download some otherwise inaccessible files such as the ones within the $Extend folder.

The filesystem from which to extract the file must be unmounted, otherwise the call will fail.

This function returns 0 on success or -1 on error.

This long-running command can generate progress notification messages so that the caller can display a progress bar or indicator. To receive these messages, the caller must register a progress event callback. See "GUESTFS_EVENT_PROGRESS".

(Added in 1.33.14)

guestfs_ntfsclone_in¶

 int
 guestfs_ntfsclone_in (guestfs_h *g,
                       const char *backupfile,
                       const char *device);

Restore the "backupfile" (from a previous call to "guestfs_ntfsclone_out") to "device", overwriting any existing contents of this device.

This function returns 0 on success or -1 on error.

This function depends on the feature "ntfs3g". See also "guestfs_feature_available".

(Added in 1.17.9)