Provided by: udftools_2.0-2_amd64 
NAME
udfinfo - show information about UDF filesystem
SYNOPSIS
udfinfo [ options ] device
DESCRIPTION
udfinfo shows various information about a UDF filesystem stored either on the block device or in the disk
file image. The output from the udfinfo is suitable for parsing by external applications or scripts.
OPTIONS
-h,--help
Display the usage and the list of options.
-b,--blocksize= block-size
Specify the size of blocks in bytes. Valid block size for a UDF filesystem is power of two in
range from 512 to 32768 and must match a device logical (sector) size. If omitted, udfinfo tries
to autodetect block size. It tries logical (sector) size and then all valid block sizes.
--vatblock= vat-block
Specify the block location of the Virtual Allocation Table. Virtual Allocation Table is present
only on UDF disks with Virtual Partition Map and must be at the last written/recorded disk block.
If omitted, udfinfo for optical disc tries to detect the last recorded block with fallback to the
last block of block device or disk file image. In most cases this fallback does not have to work
and for disk file images with Virtual Allocation Table is necessary to specify correct location.
Virtual Allocation Table contains locations of UDF disk blocks needed to read data storage,
determinate used and free space blocks, read File Set Identifier and calculate Windows specific
Volume Serial Number. Also on disks with UDF revisions higher then 1.50 it contains Logical Volume
Identifier and overwrite one stored in Logical Volume Descriptor.
--locale
Encode UDF string identifiers on output according to current locale settings (default).
--u8 Encode UDF string identifiers on output to 8 bit OSTA Compressed Unicode format, equivalent to
Latin1 (ISO-8859-1). This will work only for strings which Unicode code points are below U+100.
--u16 Encode UDF string identifiers on output to 16 bit OSTA Compressed Unicode format, equivalent to
UCS-2BE.
--utf8 Encode UDF string identifiers on output to UTF-8.
EXIT STATUS
udfinfo returns 0 if successful, non-zero if there are problems like block device does not contain UDF
filesystem.
OUTPUT FORMAT
First part of the udfinfo standard output contains information in key=value format. List of all keys with
their meaning are in the following table:
filename File name of the selected block device or disk file image
label label is an alias for lvid, see udflabel(8) section UDF LABEL AND UUID
uuid UUID are first 16 hexadecimal lowercase digits of fullvsid, but see udflabel(8)
section UDF LABEL AND UUID
lvid UDF Logical Volume Identifier stored in UDF Logical Volume Descriptor
vid UDF Volume Identifier stored in UDF Primary Volume Descriptor
vsid fullvsid after uuid part, typically 17.-127. character
fsid UDF File Set Identifier stored in UDF File Set Descriptor
fullvsid UDF Volume Set Identifier stored in UDF Primary Volume Descriptor
winserialnum Windows specific Volume Serial Number
blocksize UDF block size
blocks Number of all blocks on the selected block device or disk file image
usedblocks Number of used space blocks on UDF disk for data storage
freeblocks Number of free space blocks on UDF disk for data storage
behindblocks Number of blocks which are behind the last block used by UDF disk
numfiles Number of stored files on UDF disk
numdirs Number of stored directories on UDF disk
udfrev UDF revision needed for reading UDF disk
udfwriterev UDF revision needed for writing or modifying UDF disk
vatblock UDF block location of the Virtual Allocation Table (visible only when available)
integrity UDF integrity of Logical Volume, one of: opened, closed, unknown
accesstype UDF Access Type, one of: overwritable, rewritable, writeonce, readonly,
pseudo-overwritable, unknown
When UDF integrity is not closed it means that the UDF disk was not properly unmounted, is in
inconsistent state and needs repairing.
All UDF string identifiers are stored on UDF disk in Unicode, therefore they are locale or code page
agnostic. Options --locale, --u8, --u16 and --utf8 controls how are identifiers encoded on output.
All newline characters from the UDF string identifiers are removed, so it is guaranteed that the newline
character is present only as a separator.
Second part of the udfinfo standard output contains list of UDF block types stored on device, one per
line in the following format:
start=block-num, blocks=block-count, type=block-type
With meaning that block-type starts at UDF block block-num and span block-count blocks on device.
Windows specific Volume Serial Number is a non-standard 32 bit checksum, calculated as four separate 8
bit XOR checksums of 512 bytes long UDF File Set Descriptor. Therefore it cannot be set or changed as
opposite to UUID which is moreover 64 bit long. This non-standard checksum is used only by Windows
systems (since Windows 98 era when it was introduced) and can be displayed on Windows systems by
applications like vol, dir or fsutil.
LIMITATIONS
udfinfo is not able to read Metadata Partition and Virtual Allocation Table stored outside of Information
Control Block yet. Therefore determining used and free space blocks, reading File Set Identifier and
calculating Windows specific Volume Serial Number may not be available for some Write Once media and
disks with UDF revisions higher then 2.01 which have Metadata Partition.
AUTHOR
Pali Rohár <pali.rohar@gmail.com>
AVAILABILITY
udfinfo is part of the udftools package since version 2.0 and is available from
https://github.com/pali/udftools/.
SEE ALSO
mkudffs(8), pktsetup(8), udflabel(8), cdrwtool(1), wrudf(1)