показать информацию о файловой системе UDF (show information about UDF filesystem)
Имя (Name)
udfinfo — show information about UDF filesystem
Синопсис (Synopsis)
udfinfo [ options ] device
Описание (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.
Параметры (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 a power of two in the range from 512
to 32768 and must match a device logical (sector) size. If
omitted, udfinfo tries to autodetect block size. First it
tries logical (sector) size and then all valid block
sizes.
--startblock= start-block
Specify the block location where the UDF filesystem
starts. It is used for calculating the block location of
the Volume Recognition Sequence (32 kB after the start
block) and the first Anchor Volume Descriptor Pointer (256
blocks after the start block).
Normally start block is 0, but for Multisession UDF
optical discs it is the block location where the last
session of Multisession UDF disc starts.
If omitted, udfinfo for optical disc tries to detect start
block of the last session from disc Table Of Contents.
Otherwise value 0 is used.
For accessing some previous session of Multisession UDF
optical disc, it is required to specify correct block
where that previous session starts. And also to specify
where that session ends via --lastblock option.
For Multisession UDF disc images stored in file there is
no way to detect where the last session starts and
therefore it is necessary to specify the correct start
block location manually from the original optical disc
Table Of Contents.
(Option available since udfinfo 2.3)
--lastblock= last-block
Specify the block location where the UDF filesystem ends.
It is used for calculating the block location of second
and third Anchor Volume Descriptor Pointer (256 blocks
prior the last block and the last block itself).
Normally last block is number of disk blocks minus one,
but for Multisession UDF optical discs when reading
different session than the last one (specified by
--startblock) it is the block location where the specified
session ends.
If omitted, udfinfo for optical disc tried to detect the
last recorded block with fallback to the last block of
device or disk file image.
For accessing some previous session of Multisession UDF
optical disc, it is required to specify correct value for
both --startblock and --lastblock options.
(Option available since udfinfo 2.3)
--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 or block specified by
--lastblock. In most cases, this fallback does not have to
work and for disk file images with Virtual Allocation
Table it is necessary to specify the 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, it contains
Logical Volume Identifier and overwrite previously 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 without leading Compression ID
byte, which is equivalent to Latin1 (ISO-8859-1) encoding.
This will work only for strings which all Unicode code
points are below U+100.
--u16 Encode UDF string identifiers on output to 16-bit OSTA
Compressed Unicode format without leading Compression ID
byte, which is equivalent to UTF-16BE.
--utf8 Encode UDF string identifiers on output to UTF-8.
Статус выхода (Exit)
udfinfo returns 0 if successful, non-zero if there are problems
like a block device does not contain UDF filesystem.
Формат вывода (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
owner UDF Logical Volume Info1 stored in UDF
Implementation Use Volume Descriptor, represents
Owner name, person creating the medium or
filesystem (available since udfinfo 2.3)
organization
UDF Logical Volume Info2 stored in UDF
Implementation Use Volume Descriptor, represents
Organization name responsible for creating the
medium or filesystem (available since udfinfo 2.3)
contact
UDF Logical Volume Info3 stored in UDF
Implementation Use Volume Descriptor, represents
Contact information for the medium or filesystem
(available since udfinfo 2.3)
appid UDF Application Identifier stored in UDF Primary
Volume Descriptor, identifies application that
created medium or filesystem (available since
udfinfo 2.3)
impid UDF Developer Identifier stored in UDF
Implementation Identifier of UDF Primary Volume
Descriptor, uniquely identifies the implementation
which created medium or filesystem (available since
udfinfo 2.3)
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
startblock
Block location where the UDF filesystem starts
(visible only when non-zero, available since
udfinfo 2.3)
lastblock
Block location where the UDF filesystem ends
(visible only when it is not same as the last block
on disk, available since udfinfo 2.3)
vatblock
Block location of the UDF 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
softwriteprotect
Status of UDF SoftWriteProtect flag, either yes or
no (available since udfinfo 2.2)
hardwriteprotect
Status of UDF HardWriteProtect flag, either yes or
no (available since udfinfo 2.2)
When UDF integrity is not closed it means that the UDF disk was
not properly unmounted, is in an inconsistent state and needs
repairing.
When either softwriteprotect or hardwriteprotect flag is set then
UDF disk should be treated as read-only.
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 opposed to UUID which is 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.exe.
Ограничения (Limitations)
udfinfo prior to version 2.3 was unable to handle Multisession
UDF discs correctly. It always printed only information about the
first session (the oldest one) and not about the last session
(the most recent).
udfinfo prior to version 2.2 was unable to print Unicode strings
with code points above U+FFFF correctly.
udfinfo prior to version 2.2 was unable to read Metadata
Partition. Therefore, determining used and free space blocks,
reading File Set Identifier and calculating Windows-specific
Volume Serial Number did not have to be available or correctly
calculated for disks with UDF revisions higher than 2.01 which
had Metadata Partition.
udfinfo prior to version 2.1 was unable to read Virtual
Allocation Table stored outside of Information Control Block.
Therefore above limitation applied also for some Write Once
media.
