xorrisofs - Online in the Cloud

PROGRAM:

NAME

xorrisofs - Emulation of ISO 9660 program mkisofs by program xorriso

SYNOPSIS

xorrisofs [ options ] [-o filename ] pathspec [pathspecs ...]

DESCRIPTION

xorrisofs produces Rock Ridge enhanced ISO 9660 filesystems and add-on sessions to such
filesystems. Optionally it can produce Joliet directory trees too.

xorrisofs understands options of program mkisofs from cdrtools by Joerg Schilling. Its
implementation is part of program xorriso which shares no source code with cdrtools.

ISO 9660, Rock Ridge, Joliet, HFS+:
ISO 9660 (aka ECMA-119) is a read-only filesystem that is mainly used for optical media
CD, DVD, BD, but may also reside on other storage devices like disk files, USB sticks or
disk partitions. It is widely readable by many operating systems and by boot facilities of
personal computers.
ISO 9660 describes directories and data files by very restricted filenames with no
distinction of upper case and lower case. Its metadata do not comply to fundamental POSIX
specifications.
Rock Ridge is the name of a set of additional information which enhance an ISO 9660
filesystem so that it can represent a POSIX compliant filesystem with ownership, access
permissions, symbolic links, and other attributes. Rock Ridge allows filenames of up to
255 bytes and paths of up to 1024 bytes.
xorrisofs produces Rock Ridge information by default. It is strongly discouraged to
disable this feature.
Joliet is the name of an additional directory tree which provides filenames up to 64
characters encoded as UTF-16. A Joliet tree is mainly interesting for reading the ISO
image by operating systems of Microsoft Corporation. Production of this directory tree
may be enabled by option -J.
ISO 9660:1999 is the name of an additional directory tree which provides longer filenames.
It allows single file names to have up to 207 characters. It might be of use with some
older computer system boot facilities which read neither Rock Ridge nor Joliet but need
longer filenames nevertheless. Production of this directory tree may be enabled by option
-iso-level 4.
HFS+ is the name of a filesystem which is normally used for writing and reading on hard
disks and similar devices. It is possible to embed a HFS+ partition into the emerging ISO
9660 image and to mark it by Apple Partition Map entries. This interferes with options
which copy data into the first 32 KiB of the ISO image, like -G or -isohybrid-mbr. See
option -hfsplus.
The main purpose for having an embedded HFS+ partition is booting of certain models of
Apple computers.

Inserting files into the ISO image:
xorrisofs deals with two kinds of file addresses:
disk_path is a path to an object in the local filesystem tree.
iso_rr_path is the Rock Ridge address of a file object in the ISO image. If no Rock Ridge
information shall be stored in an emerging ISO, then the names will get mapped to ISO 9660
names of limited length and character set.

A program argument is handled as a pathspec, if it is not recognized as original mkisofs
option or additional xorrisofs option. A pathspec depicts an input file object by a
disk_path. If option -graft-points is not present, then the behavior depends on the file
type of disk_path. Directories get merged with the /-directory of the ISO image. Files of
other types get copied into the /-directory.
If -graft-points is present then each pathspec gets split at the first occurence of the
=-character. The part before the = is taken as target, i.e. the iso_rr_path for the file
object in the ISO image. The part after the first = is taken as source, i.e. the disk_path
of the input object.
It is possible to make =-characters part of the iso_rr_path by preceding them with a
\-character. The same must be done for \-characters which shall be part of the
iso_rr_path.

If the source part of the pathspec leads to a directory, then all files underneath this
directory get inserted into the image, too. It is possible to exclude particular files
from being inserted by help of option -m.
In case that target already exists, the following rules apply: Directories and other files
may overwrite existing non-directories. Directories get merged with existing directories.
Non-directories may not overwrite existing directories.

Relation to program xorriso:
xorrisofs is actually a command mode of program xorriso, which gets entered either by
xorriso command "-as mkisofs" or by starting the program by one of the names "xorrisofs",
"mkisofs", "genisoimage", or "genisofs".
This command mode can be left by argument "--" which leads to generic xorriso command
mode. See man xorriso for its description.

xorriso performs image reading and writing by help of libburn, which is mainly intended
for optical drives, but also operates on all POSIX file types except directories.
The program messages call any image file a "drive". File types which are not supported for
reading are reported as "blank". The reported free media space may be quite fictional.
Nevertheless xorrisofs does not operate directly on optical drives, but rather forces
libburn to regard them as general device files. So for writing of sequential optical
media (CD, DVD-R, DVD+R, BD-R) one will have to use a burn program. E.g the cdrecord
emulation of xorriso. See EXAMPLES.

OPTIONS

Image loading:

The following options control loading of an existing ISO image for the purpose of
preparing a suitable add-on session. If they are missing then a new image is composed
from scratch.

-M disk_path
Set the path from which to load the existing ISO image directory tree on which to
base the upcomming directory tree as add-on session. The path must lead to a
random-access readable file object. On GNU/Linux: regular data files or block
device files.
A special kind of pseudo disk_path has the form "/dev/fd/"number. It depicts the
open file descriptor with the given number, regardless whether the operating system
supports this feature by file nodes in /dev/fd or not. E.g. /dev/fd/3 is file
descriptor 3 which was opened by the program that later started xorriso.

-prev-session disk_path
Alias of -M.

-dev disk_path
Alias of -M.

-C last_session_start,next_writeable_address
Set the 2 KiB block address last_session_start from where to read the ISO image out
of the file given by option -M.
Separated by a comma, set the next_writeable_address to which the add-on session
will finally be written. Decisive is actually the block address which the intended
readers will have to use as superblock address on the intended medium.
Both values can be inquired from optical media by help of burn programs and
cdrecord option -msinfo. xorriso itself can obtain it in its cdrecord emulation. Do
not let it load the drive, but rather do this manually or by a program like dd
which reads a few bytes. Only then it is sure that the device driver knows the true
readable size of the medium.
dd if=/dev/... count=1 >/dev/null 2>&1
values=$(xorriso -as cdrecord dev=/dev/... -msinfo)
echo $values
Option -C may be used without option -M to create an ISO image from scratch and
prepare it for being finally written to a block address other than 0. Parameter
last_session_start must then be set to 0.

-cdrecord-params last_session_start,next_writeable_address
Alias of -C.

Settings for file insertion:

-path-list disk_path
Read pathspecs line-by-line from disk_file and insert the depicted file objects
into the ISO image. If disk_path is "-" then read the pathspecs from standard
input.

--quoted_path_list disk_path
Like option -path-list but reading quoted words rather than plain lines.
Whitespace outside of quotes will be discarded. On the other hand it is possible to
represent pathspecs which contain newline characters.
The double quotation mark " and the single quotation mark ' can be used to enclose
whitespace and make it part of pathspecs. Each mark type can enclose the marks of
the other type. A trailing backslash \ outside quotations or an open quotation
cause the next input line to be appended.

-f
Resolve symbolic links on disk rather than storing them as symbolic links in the
ISO image.

-follow-links
Alias of -f.

-graft-points
Enable interpretation of input file pathspecs as combination of iso_rr_path and
disk_path, separated by a =-character.

-m disk_pattern
Exclude files from being inserted into the image. Silently ignored are those files
of which the disk_path matches the given shell parser pattern. If no /-character
is part of the pattern, then it gets matched against the leaf name of the disk
file.
It is possible to give more than one -m option.

-exclude
Alias of -m.

-x
Alias of -m.

-old-exclude
Alias of -m.

-exclude-list disk_path
Perform -m using each line out of file disk_path as argument disk_pattern.

-z
Enable recognition and proper processing of zisofs compressed files as produced by
program mkzftree. These files will get equipped with the necessary meta data so
that a Linux kernel will recognize them and deliver their content in uncompressed
form.

-transparent-compression
Alias of -z.

-root iso_rr_path
Insert all files under the given iso_rr_path. If option -graft-points is given,
then iso_rr_path is prepended to each target part of a pathspec.
The default for -root is "/".

-old-root iso_rr_path
Enable incremental insertion of files into the loaded image. The effective target
and source addresses of given pathspecs get compared whether the target already
exists in the ISO image and is still identical to the source on disk. Metadata in
the ISO image will get adjusted, if they differ from those on disk. New files and
files with changed content will get newly added. Target files which do not exist
in any of the according pathspec sources will get removed from the ISO directory
tree.
If the effective setting of -root differs from the iso_rr_path given with
-old-root, then the files underneath the -old-root directory get cloned underneath
the -root directory. Cloning happens before file comparison.

--old-root-no-ino
Disable recording and use of disk inode numbers. If no disk inode numbers are
recorded, then option -old-root will have to read disk file content and compare it
with the MD5 checksum that is recorded in the ISO image.
With recorded disk inode numbers and with credible ctime and mtime, it is possible
to detect potential changes in the content without actually reading it. A loophole
remains if multiple different filesystems may get mounted at the same directory,
like it is habit with /mnt. In this case one has to use option --old-root-devno or
disable the inode number shortcut by --old-root-no-ino.

--old-root-devno
Enable comparison of recorded device numbers together with recorded inode numbers.
This works only with good old stable device numbers which get out of fashion,
regrettably. If the hard disk has a different device number after each reboot, then
this comparison will see all files as changed and thus prevent any incremental size
saving.

--old-root-no-md5
Disable recording and use of MD5 checksums for data file content. If neither
checksums and nor disk inode numbers are recorded, then option -old-root will have
to read ISO image file content when comparing it with disk file content.

Settings for image production:

-o disk_path
Set the output file address for the emerging ISO image. If the address exists as
regular file, it will be truncated to length 0 when image production begins. It may
not already exist as directory. If it does not exist yet then its parent directory
must exist and a regular file will get created.
A special kind of pseudo disk_path has the form "/dev/fd/"number. It depicts the
open file descriptor with the given number, regardless whether the operating system
supports this feature by file nodes in /dev/fd or not. E.g. /dev/fd/4 is file
descriptor 4 which was opened by the program that later started xorriso.
Default is standard output (/dev/fd/1) which may also be set by disk_path "-".

-output disk_path
Alias of -o.

--stdio_sync "on"|"off"|"end"|number
Set the number of bytes after which to force output to disk in order to keep the
memory from being clogged with lots of pending data for slow devices. "on" is the
same as "16m". Forced output can be disabled by "off", or be delayed by "end"
until all data are produced. If a number is chosen, then it must be at least 64k.
The default with xorriso mkisofs emulation is --stdio_sync "off".
xorriso uses an inner fifo buffer with default size 4 MiB. So forcing the operating
system i/o cache to disk does not necessarily block the simultaneous production of
more image content.

--emul-toc
Write a second superblock with the first session into random-access files. If
further sessions get appended and the first superblock gets updated, then the
second superblock will not be overwritten. So it is still possible to mount the
first session and to find the start blocks of the further sessions.
The price is 64 KiB extra space consumption. If -partition_offset is non-zero, then
it is 128 KiB plus twice the partition setup.

--no-emul-toc
Do not write a second superblock with the first session into random-access files.
This is the default.

--sort-weight weight_number iso_rr_path
Attribute a LBA weight number to regular files. If iso_rr_path leads to a directory
then all regular files underneath will get the weight_number.
The weight_number may range from -2147483648 to 2147483647. The higher it is, the
lower will be the block address of the file data in the emerging ISO image.
Currently the El Torito boot catalog has a hardcoded weight of 1 billion. Normally
it should occupy the block with the lowest possible address. Data files get added
or loaded with initial weight 0. Boot image files have a default weight of 2.

--sort-weight-list disk_path
Read pairs of weight number and iso_rr_path from a file of the local filesystem.
Apply each pair like with --sort-weight.
Only the last --sort-weight-list or --sort-weight-patterns of a xorrisofs run gets
into effect.
The weight number is read from the start of the line. The iso_rr_path part of an
input line begins immediately after the first blank or tab character of the line.
Notes for the case that this feature is used within a sequence of generic xorriso
commands (not an issue with a pure mkisofs emulation run):
The addressed files must already be in the ISO image model when you execute
-as mkisofs --sort-weight-list disk_path --
Several such commands may be used to apply more than one weight file.
Data files which are loaded by -indev or -dev get a weight between 1 and 2 exp 28 =
268,435,456, depending on their block address. This shall keep them roughly in the
same order if the write method of modifying is applied.

--sort-weight-patterns disk_path
Like --sort-weight-list , but expanding the iso_rr_paths as shell parser patterns
and applying --sort-weight to each matching file.

-dir-mode mode
Set the access permissions for all directories in the image to the given mode which
is either an octal number beginning with "0" or a comma separated list of
statements of the form [ugoa]*[+-=][rwxst]* . E.g. ug=rx,a-rwx

-file-mode mode
Like -dir-mode but for all regular data files in the image.

-pad
Add 300 KiB to the end of the produced ISO image. This circumvents possible read
errors from ISO images which have been written to CD media in TAO mode. The
additional bytes are claimed as part of the ISO image if not --emul-toc is given.
Option -pad is the default.

-no-pad
Disable padding of 300 KiB to the end of the produced ISO image. This is safe if
the image is not meant to be written on CD or if it gets written to CD as only
track in write mode SAO.

--old-empty
Use the old way of of giving block addresses in the range of [0,31] to files with
no own data content. The new way is to have a dedicated block to which all such
files will point.

Settings for standards compliance:

-iso-level number
Specify the ISO 9660 version which defines the limitations of file naming and data
file size. The naming restrictions do not apply to the Rock Ridge names but only to
the low-level ISO 9660 names. There are three conformance levels:
Level 1 allows ISO names of the form 8.3 and file size up to 4 GiB - 1.
Level 2 allows ISO names with up to 32 characters and file size up to 4 GiB - 1.
Level 3 allows ISO names with up to 32 characters and file size of up to 400 GiB -
200 KiB. (This size limitation is set by the xorriso implementation and not by ISO
9660 which would allow nearly 8 TiB.)
Pseudo-level 4 enables production of an additional ISO 9660:1999 directory tree.

-disallow_dir_id_ext
Do not follow a bad habit of mkisofs which allows dots in the ISO names of
directories. On the other hand, some bootable GNU/Linux images depend on this bad
habit.

-U
This option allows ISO file names without dot and up to 37 characters, ISO file
paths longer than 255 characters, and all ASCII characters in file names. Further
it omits the semicolon and the version numbers at the end of ISO names.
This all violates ISO 9660 specs.

-untranslated-filenames
Alias of -U.

-untranslated_name_len number
Allow ISO file names up to the given number of characters without any character
conversion. The maximum number is 96. If a file name has more characters, then
image production will fail deliberately.
This violates ISO 9660 specs.

-allow-lowercase
Allow lowercase character in ISO file names.
This violates ISO 9660 specs.

-relaxed-filenames
Allow nearly all 7-bit characters in ISO file names. Not allowed are 0x0 and '/'.
If not option -allow-lowercase is given, then lowercase letters get converted to
uppercase.
This violates ISO 9660 specs.

-d
Do not add trailing dot to ISO file names without dot.
This violates ISO 9660 specs.

-omit-period
Alias of -d.

-l
Allow up to 31 characters in ISO file names.

-full-iso9660-filenames
Alias of -l.

-max-iso9660-filenames
Allow up to 37 characters in ISO file names.
This violates ISO 9660 specs.

-N
Omit the semicolon and the version numbers at the end of ISO names.
This violates ISO 9660 specs.

-omit-version-number
Alias of -N.

Settings for standards extensions:

-R
With mkisofs this option enables Rock Ridge extensions. xorrisofs produces them by
default. It is strongly discouraged to disable them by option --norock.

-rock
Alias of -R.

-r
Set Rock Ridge user and group id of all files in the ISO image to 0. Grant
r-permissions to all. Deny all w-permissions. If any x-permission is set, grant
x-permission to all. Remove s-bit and t-bit.

-rational-rock
Alias of -r.

--norock
This option disables the production of Rock Ridge extensions for the ISO 9660 file
objects. The multi-session capabilities of xorrisofs depend much on the naming
fidelity of Rock Ridge. So it is strongly discouraged to disable it by this option.

-file_name_limit number
Set the maximum permissible length for file names in the range of 64 to 255. Path
components which are longer than the given number will get truncated and have their
last 33 bytes overwritten by a colon ':' and the hex representation of the MD5 of
the first 4095 bytes of the whole oversized name. Potential incomplete UTF-8
characters will get their leading bytes replaced by '_'.
Linux kernels up to at least 4.1 misrepresent names of length 254 and 255. If you
expect such names in or under disk_paths and plan to mount the ISO by such Linux
kernels, consider to set -file_name_limit 253.

-D The standard ECMA-119 demands that no path in the image shall have more than 8 name
components or 255 characters. Therefore it would be necessary to move deeper
directory trees to a higher directory. Rock Ridge offers an opportunity to let
these relocated directories appear at their orginal deep position, but this feature
might not be implemented properly by operating systems which mount the image.
Option -D disables this deep directory relocation, and thus violates ISO 9660
specs.
xorrisofs has -D set by default. If given explicitly then it overrides the options
-rr_reloc_dir and -hide-rr-moved.

-disable-deep-relocation
Alias of -D.

-rr_reloc_dir name
Enable the relocation of deep directories and thus avoid ECMA-119 file paths of
more than 8 name components or 255 characters. Directories which lead to such file
paths will get moved to a directory in the root directory of the image. Its name
gets set by this option. It is permissible to use the root directory itself.
The overall directory tree will appear originally deep when interpreted as Rock
Ridge tree. It will appear as re-arranged if only ECMA-119 information is
considered.
If the given relocation target directory does not already exist when image
production begins, then it will get created and marked for Rock Ridge as relocation
artefact. At least on GNU/Linux it will not be displayed in mounted Rock Ridge
images.
The name must not contain a '/' character after its first character and it must not
be longer than 255 bytes.
This option has no effect if option -D is present.

-hide-rr-moved
Alias of -rr_reloc_dir "/.rr_moved"

--for_backup
Enable options which improve backup fidelity: --acl, --xattr, --md5, --hardlinks.

--acl
Enable recording and loading of ACLs from GNU/Linux or FreeBSD (see man getfacl,
man acl). They will not be in effect with mounted ISO images. But xorriso can
restore them on the same systems when extracting files from the ISO image.

--xattr
Enable recording and loading of GNU/Linux or FreeBSD extended attributes in user
namespace (see man getfattr and man attr, man getextattr and man 9 extattr,
respectively). They will not be in effect with mounted ISO images. But xorriso can
restore them on the same systems when extracting files from the ISO image.

--md5
Enable recording of MD5 checksums for the overall ISO image and for each single
data file in the image. xorriso can check the content of an ISO image with these
sums and raise alert on mismatch. See man xorriso, options -check_media,
check_md5_r. xorriso can print recorded MD5 checksums. E.g. by:
-find / -exec get_md5

--hardlinks
Enable loading and recording of hardlink relations. Search for families of iso_rr
files which stem from the same disk file, have identical content filtering and have
identical properties. The members of each family get the same inode number in the
ISO image.
Whether these numbers are respected at mount time depends on the operating system.
xorriso can create hardlink families when extracting files from the ISO image.

--scdbackup_tag disk_path record_name
Append a scdbackup checksum record to the image. This works only if the parameter
next_writeable_address of option -C is 0. If disk_path is not an empty string,
then append a scdbackup checksum record to the end of this file. record_name is a
word that gets part of tag and record.
Program scdbackup_verify will recognize and verify tag and file record.

-J
Enable the production of an additional Joliet directory tree along with the ISO
9660 Rock Ridge tree.

-joliet
Alias of -J.

-joliet-long
Allow 103 characters in Joliet file names rather than 64 as is prescribed by the
specification. Allow Joliet paths longer than the prescribed limit of 240
characters.
Oversized names get truncated. Without this option, oversized paths get excluded
from the Joliet tree.

-joliet-utf16
Encode Joliet file names in UTF-16BE rather than UCS-2. The difference is with
characters which are not present in UCS-2 and get encoded in UTF-16 by 2 words of
16 bit each. Both words then stem from a reserved subset of UCS-2.

-hfsplus
Enable the production of an additional HFS+ filesystem inside the ISO 9660 image
and mark it by Apple Partition Map (APM) entries in the System Area, the first 32
KiB of the image.
This may collide with options like -G or -isohybrid-mbr which submit user data for
inclusion in the same address range. The first 8 bytes of the System Area get
overwritten by { 0x45, 0x52, 0x08 0x00, 0xeb, 0x02, 0xff, 0xff } which can be
executed as x86 machine code without negative effects. So if an MBR gets combined
with this feature, then its first 8 bytes should contain no essential commands.
The next blocks of 2 KiB in the System Area will be occupied by APM entries. The
first one covers the part of the ISO image before the HFS+ filesystem metadata. The
second one marks the range from HFS+ metadata to the end of file content data. If
more ISO image data follow, then a third partition entry gets produced. Other
features of xorriso might cause the need for more APM entries.
Be aware that HFS+ is case-insensitive although it can record file names with
upper-case and lower-case letters. Therefore, file names from the iso_rr name tree
may collide in the HFS+ name tree. In this case they get changed by adding
underscore characters and counting numbers. In case of very long names, it might be
necessary to map them to "MANGLED_...".

-hfsplus-serial-no
Set a string of 16 digits "0" to "9" and letters "a" to "f", which will be used as
unique serial number of an emerging HFS+ filesystem.

-hfsplus-block-size number
Set the allocation block size to be used when producing HFS+ filesystems.
Permissible are 512, 2048, or 0. The latter lets the program decide.

-apm-block-size number
Set the block size to be used when describing partitions by an Apple Partition Map.
Permissible are 512, 2048, or 0. The latter lets the program decide.
Note that size 512 is not compatible with production of GPT, and that size 2048
will not be mountable -t hfsplus at least by older Linux kernels.

-hfsplus-file-creator-type creator type iso_rr_path
Set the HFS+ creator and type attributes of a file in the emerging image. These
are two codes of 4 characters each.

-hfs-bless-by blessing iso_rr_path
Issue a HFS+ blessing. They are roles which can be attributed to up to four
directories and a data file:
"ppc_bootdir", "intel_bootfile", "show_folder", "os9_folder", "osx_folder".
They may be abbreviated as "p", "i", "s", "9", and "x".
Each such role can be attributed to at most one file object. "intel_bootfile" is
the one that would apply to a data file. All others apply to directories. No file
object can bear more than one blessing.

-hfs-bless disk_path
Issue HFS+ blessing "ppc_bootdir" to the directory which stems from the directory
disk_path in the local filesystem tree.
This works only if there is at least one data file underneath the directory.
disk_path can become ambigous if files from different local filesystem sub-trees
are put into the same sub-tree of the ISO image. Consider to use -hfs-bless-by "p"
for unambigous addressing via iso_rr_path.

Settings for file hiding:

-hide disk_path_pattern
Make files invisible in the directory tree of ISO 9660 and Rock Ridge, if their
disk_path matches the given shell parser pattern. The data content of such hidden
files will be included in the resulting image, even if they do not show up in any
directory. But you will need own means to find nameless data in the image.
This command does not apply to the boot catalog.

-hide-list disk_path
Perform -hide using each line out of file disk_path as argument disk_path_pattern.

-hide-joliet disk_path_pattern
Like option -hide but making files invisible in the directory tree of Joliet, if
their disk_path matches the given shell parser pattern.

-hide-joliet-list disk_path
Perform -hide-joliet using each line out of file disk_path as argument
disk_path_pattern.

-hide-hfsplus disk_path_pattern
Like option -hide but making files invisible in the directory tree of HFS+, if
their disk_path matches the given shell parser pattern.

-hide-hfsplus-list disk_path
Perform -hide-hfsplus using each line out of file disk_path as argument
disk_path_pattern.

ISO image ID strings:

The following strings and file addresses get stored in the Primary Volume Descriptor of
the ISO9660 image. The file addresses are ISO 9660 paths. These files should have
iso_rr_paths which consist only of the characters [A-Z0-9_] and exactly one dot which
separates at most 8 characters from at most 3 characters.

-V text
Set the Volume Id of the ISO image. xorriso accepts any text up to 32 characters,
but according to rarely obeyed specs stricter rules apply:
Conformant are ASCII characters out of [A-Z0-9_]. Like: "IMAGE_23"
Joliet allows 16 UCS-2 characters. Like: "Windows name"
Be aware that the volume id might get used automatically as name of the mount point
when the medium is inserted into a playful computer system.

-volid text
Alias of -V.

-volset text
Set the Volume Set Id of the ISO image. Permissible are up to 128 characters.

-P text
Set the Publisher Id of the ISO image. This may identify the person or organisation
who specified what shall be recorded. Permissible are up to 128 characters.

-publisher text
Alias of -P.

-A text
Set the Application Id of the ISO image. This may identify the specification of
how the data are recorded. Permissible are up to 128 characters.
The special text "@xorriso@" gets converted to the id string of xorriso which is
normally written as Preparer Id. It is a wrong tradition to write the program id as
Application Id.

-appid text
Alias of -A.

-sysid text
Set the System Id of the ISO image. This may identify the system which can
recognize and act upon the content of the System Area in image blocks 0 to 15.
Permissible are up to 32 characters.

-p text
Set the Preparer Id of the ISO image. This may identify the person or other entity
which controls the preparation of the data which shall be recorded. Normally this
should be the id of xorriso and not of the person or program which operates
xorriso. Please avoid to change it. Permissible are up to 128 characters.
The special text "@xorriso@" gets converted to the id string of xorriso which is
default at program startup.

-preparer text
Alias of -p.

-abstract iso_path
Set the address of the Abstract File of the ISO image. This should be the ISO 9660
path of a file in the image which contains an abstract statement about the image
content. Permissible are up to 37 characters.

-biblio iso_path
Set the address of the Biblio File of the ISO image. This should be the ISO 9660
path of a file in the image which contains bibliographic records. Permissible are
up to 37 characters.

-copyright iso_path
Set the address of the Copyright File of the ISO image. This should be the ISO 9660
path of a file in the image which contains a copyright statement. Permissible are
up to 37 characters.

--modification-date=YYYYMMDDhhmmsscc
Set a timestring that overrides ISO image creation and modification timestamps
literally. It must consist of 16 decimal digits which form YYYYMMDDhhmmsscc, with
YYYY between 1970 and 2999. Time zone is GMT. It is supposed to match this GRUB
line:
search --fs-uuid --set YYYY-MM-DD-hh-mm-ss-cc
E.g. 2010040711405800 is 7 Apr 2010 11:40:58 (+0 centiseconds).

--application_use character|0xXY|disk_path
Specify the content of the Application Use field which can take at most 512 bytes.
If the parameter of this command is empty, then the field is filled with 512
0-bytes. If it is a single character, then it gets repeated 512 times. If it
begins by "0x" followed by two hex digits [0-9a-fA-F], then the digits are read as
byte value which gets repeated 512 times.
Any other parameter text is used as disk_path to open a data file and to read up to
512 bytes from it. If the file is smaller than 512 bytes, then the remaining bytes
in the field get set to binary 0.

El Torito Bootable ISO images:

The precondition for a bootable ISO image is to have in the ISO image the files of a boot
loader. The boot facilities of computers get directed to such files, which usually execute
further program files from the ISO image. xorrisofs can produce several kinds of boot
block or boot record, which become part of the ISO image, and get interpreted by the
according boot facility.

An El Torito boot record points the bootstrapping facility to a boot catalog with one or
more boot images, which are binary program files stored in the ISO image. The content of
the boot image files is not in the scope of El Torito.
xorriso composes the boot catalog according to the boot image files given and structured
by options -b, -e, -el-torito-alt-boot, and --efi-boot. Often it contains only one entry.
El Torito gets interpreted by boot facilities PC-BIOS and EFI. Most bootable GNU/Linux
CDs are equipped with ISOLINUX or GRUB boot images for PC-BIOS.
xorrisofs supports the example options out of the ISOLINUX wiki, the options used in GRUB
script grub-mkrescue, and the example in the FreeBSD AvgLiveCD wiki.

For CD booting via boot facilities other than PC-BIOS and EFI, and for booting from USB
sticks or hard disks, see the next section about the System Area.

-b iso_rr_path
Specify the boot image file which shall be mentioned in the current entry of the El
Torito boot catalog. It will be marked as suitable for PC-BIOS.
With boot images from ISOLINUX and GRUB this option should be accompanied by
options -c , -no-emul-boot , -boot-load-size 4 , -boot-info-table.

-eltorito-boot iso_rr_path
Alias of -b.

-eltorito-alt-boot
Finalize the current El Torito boot catalog entry and begin a new one. A boot
image file and all its necessary options shall be specified before option
-eltorito-alt-boot. All further El Torito boot options apply to the new catalog
entry. Up to 32 catalog entries are possible.

-e iso_rr_path
Specify the boot image file which shall be mentioned in the current entry of the El
Torito boot catalog. It will be marked as suitable for EFI.
Option -e should be followed by option -no-emul-boot and no other El Torito options
before an eventual -eltorito-alt-boot.

--efi-boot iso_rr_path
Perform -eltorito-alt-boot, option -e with the given iso_rr_path, -no-emul-boot,
and again -eltorito-alt-boot. This gesture is used for achieving EFI-bootability of
the GRUB2 rescue CD.

-boot-load-size number
Set the number of 512-byte blocks to be loaded at boot time from the boot image in
the current catalog entry. Non-emulating BIOS bootimages usually need a load size
of 4. EFI boot images usually get set the number of blocks occupied by the boot
image file.
El Torito cannot represent load sizes higher than 65535.

-hard-disk-boot
Mark the boot image in the current catalog entry as emulated hard disk. (Not
suitable for any known boot loader.)

-no-emul-boot
Mark the boot image in the current catalog entry as not emulating floppy or hard
disk. (This is to be used with all known boot loaders.)
If neither -hard-disk-boot nor -no-emul-boot is given, then the boot image will be
marked as emulating a floppy. (Not suitable for any known boot loader.)

-eltorito-id text|56_hexdigits
Define the ID string of the boot catalog section where the boot image will be
listed. If the value consists of 56 characters [0-9A-Fa-f] then it is converted
into 28 bytes, else the first 28 characters become the ID string. The ID string of
the first boot image becomes the overall catalog ID. It is limited to 24
characters. Other id_strings become section IDs.

-eltorito-selcrit hexdigits
Define the Selection Criteria of the boot image. Up to 20 bytes get read from the
given characters [0-9A-Fa-f]. They get attributed to the boot image entry in the
catalog.

-boot-info-table
Overwrite bytes 8 to 63 in the current boot image. The information will be supplied
by xorriso in the course of image production: Block address of the Primary Volume
Descriptor, block address of the boot image file, size of the boot image file.

--grub2-boot-info
Overwrite bytes 2548 to 2555 in the current boot image by the address of that boot
image. The address is written as 64 bit little-endian number. It is the 2KB block
address of the boot image content, multiplied by 4, and then incremented by 5.

-c iso_rr_path
Set the address of the El Torito boot catalog file within the image. This file
address is not significant for the booting PC-BIOS or EFI, but it may later be read
by other programs in order to learn about the available boot images.

-eltorito-catalog iso_rr_path
Alias of -c.

--boot-catalog-hide
Prevent the El Torito boot catalog from appearing as file in the directory trees of
the image.

System Area, MBR, GPT, APM, other boot blocks:

The first 16 blocks of an ISO image are the System Area. It is reserved for system
dependent boot software. This may be the boot facilities and partition tables of various
hardware architectures.
A MBR (Master Boot Record) contains boot code and a partition table. It is read by
PC-BIOS when booting from USB stick or hard disk, and by PowerPC CHRP or PReP when
booting. An MBR partiton with type 0xee indicates the presence of GPT.
A GPT (GUID Partition Table) marks partitions in a more modern way. It is read by EFI
when booting from USB stick or hard disk, and may be used for finding and mounting a HFS+
partition inside the ISO image.
An APM (Apple Partition Map) marks the HFS+ partition. It is read by Macs for booting and
for mounting.
MBR, GPT and APM are combinable. APM occupies the first 8 bytes of MBR boot code. All
three do not hamper El Torito booting from CDROM.
xorrisofs supports further boot facilities: MIPS Big Endian (SGI), MIPS Little Endian
(DEC), SUN SPARC, HP-PA, DEC Alpha. Those are mutually not combinable and also not
combinable with MBR, GPT, or APM.

Several of the following options expect disk paths as input but also accept description
strings for the libisofs interval reader, which is able to cut out data from disk files or
-indev and to zeroize parts of the content: -G, -generic-boot, --embedded-boot,
--grub2-mbr, -isohybrid-mbr, -efi-boot-part, -prep-boot-part, -B, -sparc-boot,
-append_partition.
The description string consists of the following components, separated by colon ':'
"--interval:"Flags":"Interval":"Zeroizers":"Source
The component "--interval" states that this is not a plain disk path but rather a interval
reader description string.
The component Flags modifies the further interpretation:
"local_fs" demands to read from a file depicted by the path in Source.
"imported_iso" demands to read from the -indev. This works only if -outdev is not the same
as -indev. The Source component is ignored.
The component Interval consists of two byte address numbers separated by a "-" character.
E.g. "0-429" means to read bytes 0 to 429.
The component Zeroizers consists of zero or more comma separated strings. They define
which part of the read data to zeroize. Byte number 0 means the byte read from the
Interval start address. Each string may be one of:
"zero_mbrpt" demands to zeroize the MBR partition table if bytes 510 and 511 bear the MBR
signature 0x55 0xaa.
"zero_gpt" demands to check for a GPT header in bytes 512 to 1023, to zeroize it and its
partition table blocks.
"zero_apm" demands to check for an APM block 0 and to zeroize its partition table blocks.
Start_byte"-"End_byte demands to zeroize the read-in bytes beginning with number
Start_byte and ending after End_byte.
The component Source is the file path with flag "local_fs", and ignored with flag
"imported_iso".
Byte numbers may be scaled by a suffix out of {k,m,g,t,s,d} meaning multiplication by
{1024, 1024k, 1024m, 1024g, 2048, 512}. A scaled value end number depicts the last byte of
the scaled range.
E.g. "0d-0d" is "0-511".
Examples:
"local_fs:0-32767:zero_mbrpt,zero_gpt,440-443:/tmp/template.iso"
"imported_iso:45056d-47103d::"

-G disk_path
Copy at most 32768 bytes from the given disk file to the very start of the ISO
image.
Other than a El Torito boot image, the file disk_path needs not to be added to the
ISO image. It will not show up as file in the directory trees.
In multi-session situations, the special disk_path "." prevents reading of a disk
file but nevertheless causes the adjustments in the existing MBR, which were
ordered by other options.

-generic-boot disk_path
Alias of -G.

--embedded-boot disk_path
Alias of -G.

--grub2-mbr disk_path
Install disk_path in the System Area and treat it as modern GRUB2 MBR. The content
start address of the first boot image is converted to a count of 512 byte blocks,
and an offset of 4 is added. The result is written as 64 bit little-endian number
to byte address 0x1b0.

-isohybrid-mbr disk_path
Install disk_path as ISOLINUX isohybrid MBR which makes the boot image given by
option -b bootable from USB sticks and hard disks via PC-BIOS. This preparation is
normally done by ISOLINUX program isohybrid on the already produced ISO image.
The disk path should lead to one of the Syslinux files isohdp[fp]x*.bin . The MBR
gets patched according to isohybrid needs. The first partition describes the range
of the ISO image. Its start is at block 0 by default, but may be set to 64 disk
blocks by option -partition_offset 16.
For the meaning of special disk_path "." see option -G.

-isohybrid-gpt-basdat
Mark the current El Torito boot image (see options -b and -e) in GPT as partition
of type Basic Data. This works only with -isohybrid-mbr and has the same impact on
the system area as -efi-boot-part. It cannot be combined with -efi-boot-part or
-hfsplus.
The first three boot images which are marked by GPT will also show up as partition
entries of type 0xef in MBR. The MBR partition for PC-BIOS gets type 0x00 rather
than 0x17 in this case. Often the further MBR entries are the ones which actually
get used by EFI.

-isohybrid-gpt-hfsplus
Mark the current El Torito boot image (see options -b and -e) in GPT as partition
of type HFS+. Impact and restrictions are like with -isohybrid-gpt-basdat.

-isohybrid-apm-hfsplus
Mark the current El Torito boot image (see options -b and -e) in Apple Partition
Map as partition of type HFS+. This works only with -isohybrid-mbr and has a
similar impact on the system area as -hfsplus. It cannot be combined with
-efi-boot-part or -hfsplus.
The ISOLINUX isohybrid MBR file must begin by a known pattern of 32 bytes of x86
machine code which essentially does nothing. It will get overwritten by 32 bytes of
APM header mock-up.

--protective-msdos-label
Patch the System Area by a simple PC-DOS partition table where partition 1 claims
the range of the ISO image but leaves the first block unclaimed.

-partition_offset 2kb_block_adr
Cause a partition table with a single partition that begins at the given block
address. This is counted in 2048 byte blocks, not in 512 byte blocks. If the block
address is non-zero then it must be at least 16. Values larger than 16 are hardly
of use. A non-zero partition offset causes two superblocks to be generated and two
sets of directory trees. The image is then mountable from its absolute start as
well as from the partition start.
The offset value of an ISO image gets preserved when a new session is added to a
loaded image. So the value defined here is only in effect if a new ISO image gets
written.

-partition_hd_cyl number
Set the number of heads per cylinder for the MBR partition table. 0 chooses a
default value. Maximum is 255.

-partition_sec_hd number
Set the number of sectors per head for the MBR partition table. 0 chooses a
default value. Maximum is 63.
The product partition_sec_hd * partition_hd_cyl * 512 is the cylinder size. It
should be divisible by 2048 in order to make exact alignment possible. With
appended partitions and -appended_part_as_gpt there is no limit for the number of
cylinders. Else there may be at most 1024 of them. If the cylinder size is too
small to stay below the limit, then appropriate values of partition_hd_cyl are
chosen with partition_sec_hd 32 or 63. If the image is larger than 8,422,686,720
bytes, then the cylinder size constraints cannot be fulfilled for MBR. They seem
not overly important anyway. Flat block addresses in partition tables are good for
1 TiB.

-partition_cyl_align mode
Control image size alignment to an integer number of cylinders. It is prescribed
by isohybrid specs and it seems to please program fdisk. Cylinder size must be
divisible by 2048. Images larger than 8,323,596,288 bytes cannot be aligned in MBR
partition table.
Mode "auto" is default. Alignment by padding happens only if option -isohybrid-mbr
is given.
Mode "on" causes alignment by padding with option --protective-msdos-label too.
Mode "all" is like "on" but also pads up partitions from -append_partition to an
aligned size.
Mode "off" disables alignment unconditionally.

-append_partition partition_number type_code disk_path
Cause a prepared filesystem image to be appended to the ISO image and to be
described by a partition table entry in a boot block at the start of the emerging
ISO image. The partition entry will bear the size of the submitted file rounded up
to the next multiple of 2048 bytes or to the next multiple of the cylinder size.
Beware of subsequent multi-session runs. The appended partition will get
overwritten.
partition_number may be 1 to 4. Number 1 will put the whole ISO image into the
unclaimed space before partition 1. So together with most xorriso MBR or GPT
features, number 2 would be the most natural choice.
The type_code may be "FAT12", "FAT16", "Linux", or a hexadecimal number between
0x00 and 0xff. Not all those numbers will yield usable results. For a list of codes
search the Internet for "Partition Types" or run fdisk command "L". This code
matters only with MBR, not with GPT.
If some other command causes the production of GPT, then the appended partitions
will be mentioned there too, even if not -appended_part_as_gpt is given.

-appended_part_as_gpt
Marks partitions from -append_partition in GPT rather than in MBR. In this case
the MBR shows a single partition of type 0xee which covers the whole output data.
By default, appended partitions get marked in GPT only if GPT is produced because
of other options.

-efi-boot-part disk_path
Copy a file from disk into the emerging ISO image and mark it by a GPT entry as EFI
System Partition. EFI boot firmware is supposed to use a FAT filesystem image in
such a partition for booting from USB stick or hard disk.
Instead of a disk_path, the word --efi-boot-image may be given. It exposes in GPT
the content of the first El Torito EFI boot image as EFI system partition. EFI boot
images are introduced by options -e or --efi-boot. The affected EFI boot image
cannot show up in HFS+ because it is stored outside the HFS+ partition.

-chrp-boot-part
Mark the block range of the whole emerging ISO image as MBR partition of type 0x96.
This is not compatible with any other feature that produces MBR partition entries.
It makes GPT unrecognizable.
CHRP is often used in conjunction with HFS. It is not yet tested whether HFS+
filesystems produced with option -hfsplus would boot on any CHRP capable machine
which does not boot pure ISO 9660 as well.

-chrp-boot
Alias of -chrp-boot-part.

-prep-boot-part disk_path
Copy a file from disk into the emerging ISO image and mark it by a MBR partition
entry of type 0x41. PReP boot firmware is supposed to read the content of the
partition as single ELF executable file. This option is compatible with other MBR
partitions and with GPT.

-mips-boot iso_rr_path
Declare a data file in the image to be a MIPS Big Endian boot file and cause
production of a MIPS Big Endian Volume Header. This is mutually exclusive with
production of other boot blocks like MBR. It will overwrite the first 512 bytes of
any data provided by -G. Up to 15 boot files can be declared by multiple
-mips-boot options.

-mipsel-boot iso_rr_path
Declare a data file in the image to be the MIPS Little Endian boot file. This is
mutually exclusive with other boot blocks. It will overwrite the first 512 bytes
of any data provided by -G. Only a single boot file can be declared by
-mipsel-boot.

-B disk_path[,disk_path ...]
Cause one or more data files on disk to be written after the end of the ISO image.
A SUN Disk Label will be written into the first 512 bytes of the ISO image which
lists this image as partition 1 and the given disk_paths as partition 2 up to 8.
The disk files should contain suitable boot images for SUN SPARC systems.
The pseudo disk_path "..." causes that all empty partition entries become copies of
the last non-empty entry. If no other disk_path is given before "..." then all
partitions describe the ISO image. In this case, the boot loader code has to be
imported by option -G.

-sparc-boot disk_path[,disk_path ...]
Alias of -B.

-sparc-label text
Set the ASCII label text of a SUN Disk Label.

--grub2-sparc-core iso_rr_path
Cause the content address and size of the given data file in the image to be
written after the SUN Disk Label. Both numbers are counted in bytes. The address
is written as 64 bit big-endian number to byte 0x228. The size is written as 32
bit big-endian number to byte 0x230.

-hppa-cmdline text
Set the PALO command line for HP-PA. Up to 1023 characters are permitted by
default. With -hppa-hdrversion 4 the limit is 127.
Note that the first five -hppa options are mandatory, if any of the -hppa options
is given. Only option -hppa-hdrversion is allowed to be missing.

-hppa-bootloader iso_rr_path
Designate the given path as HP-PA bootloader file.

-hppa-kernel-32 iso_rr_path
Designate the given path as HP-PA 32 bit kernel file.

-hppa-kernel-64 iso_rr_path
Designate the given path as HP-PA 64 bit kernel file.

-hppa-ramdisk iso_rr_path
Designate the given path as HP-PA RAM disk file.

-hppa-hdrversion number
Choose between PALO header version 5 (default) and version 4. For the appropriate
value see in PALO source code: PALOHDRVERSION.

-alpha-boot iso_rr_path
Declare a data file in the image to be the DEC Alpha SRM Secondary Bootstrap Loader
and cause production of a boot sector which points to it. This is mutually
exclusive with production of other boot blocks like MBR.

Character sets:

Character sets should not matter as long as only english alphanumeric characters are used
for file names or as long as all writers and readers of the medium use the same character
set. Outside these constraints it may be necessary to let xorriso convert byte codes.
A conversion from input character set to the output character set is performed when an ISO
image gets written. Vice versa there is a conversion from output character set to the
input character set when an ISO image gets loaded. The sets can be defined by options
-input-charset and -output-charset, if needed.

-input-charset character_set_name
Set the character set from which to convert disk file names when inserting them
into the ISO image.

-output-charset character_set_name
Set the character set from which to convert names of loaded ISO images and to
which to convert names when writing ISO images.

Jigdo Template Extraction:

From man genisoimage: "Jigdo is a tool to help in the distribution of large files like CD
and DVD images; see http://atterer.net/jigdo/ for more details. Debian CDs and DVD ISO
images are published on the web in jigdo format to allow end users to download them more
efficiently."
If the use of libjte was enabled at compile time of xorriso, then xorrisofs can produce a
.jigdo and a .template file together with a single-session ISO image. If not, then Jigdo
options will cause a FAILURE event, which normally leads to program abort.
One may determine the ability for Jigdo by:
$ xorrisofs -version 2>&1 | grep '^libjte' && echo YES

The .jigdo file contains checksums and symbolic file addresses. The .template file
contains the compressed ISO image with reference tags instead of the content bytes of the
listed files.
Input for this process are the normal arguments for a xorrisofs session with no image
loaded, and a .md5 file which lists those data files which may be listed in the .jigdo
file and externally referenced in the .template file. Each designated file is represented
in the .md5 file by a single text line:
MD5 as 32 hex digits, 2 blanks, size as 12 decimal digits or blanks, 2 blanks, symbolic
file address
The file address in an .md5 line has to bear the same basename as the disk_path of the
file which it shall match. The directory path of the file address is decisive for To=From
mapping, not for file recognition. After To=From mapping, the file address gets written
into the .jigdo file. Jigdo restore tools will convert these addresses into really
reachable data source addresses from which they can read.
If the list of jigdo parameters is not empty, then padding will be counted as part of the
ISO image.

-jigdo-jigdo disk_path
Set the disk_path for the .jigdo file with the checksums and download addresses for
filling the holes in .template.

-jigdo-template disk_path
Set the disk_path for the .template file with the holed and compressed ISO image
copy.

-jigdo-min-file-size size
Set the minimum size for a data file to be listed in the .jigdo file and being a
hole in the .template file. size may be a plain number counting bytes, or a number
with appended letter "k", "m", "g" to count KiB (1024 bytes), MiB (1024 KiB), or
GiB (1024 MiB).

-jigdo-force-md5 disk_path_pattern
adds a regular expression pattern which will get compared with the absolute
disk_path of any data file that was not found in the .md5 list. A match causes a
MISHAP event, which normally does not abort the program run but finally causes a
non-zero exit value of the program.

-jigdo-exclude disk_path_pattern
Add a regular expression pattern which will get compared with the absolute
disk_path of any data file. A match causes the file to stay in .template in any
case.

-jigdo-map To=From
Add a string pair of the form To=From to the parameter list. If a data file gets
listed in the .jigdo file, then it is referred by the file address from its line in
the .md5 file. This file address gets checked whether it begins with the From
string. If so, then this string will be replaced by the To string and a ':'
character, before it goes into the .jigdo file. The From string should end by a '/'
character.

-md5-list disk_path
Set the disk_path where to find the .md5 input file.

-jigdo-template-compress "gzip"|"bzip2"
Choose one of "bzip2" or "gzip" for the compression of the template file. The jigdo
file is put out uncompressed.

-checksum_algorithm_iso list_of_names
Choose one or more of "md5", "sha1", "sha256", "sha512" for the auxiliary "# Image
Hex" checksums in the .jigdo file. The list_of_names may e.g. look like
"md5,sha1,sha512". Value "all" chooses all available algorithms. Note that MD5
stays always enabled.

-checksum_algorithm_template list_of_names
Choose the algorithms for the "# Template Hex" checksums in the .jigdo file. The
rules for list_of_names are the same as with -checksum_algorithm_iso.

Miscellaneous options:

-print-size
Print to stdandard output the foreseeable number of 2048 byte blocks in the
emerging ISO image. Do not produce this image.
The result depends on several settings.
If option --emul-toc is given, then padding (see -pad) is not counted as part of
the image size. In this case either use -no-pad or add 150 (= 300 KiB) to the
resulting number.
If mkisofs emulation ends after option -print-size, then the properties of the most
recently specified boot image file cannot be edited by subsequent xorriso commands.

--no_rc
Only if used as first argument this option prevents reading and interpretation of
startup files. See section FILES below.

-help
List supported options to stderr. Original mkisofs options bear their original
mkisofs description texts.

-quiet
Suppress most messages of the program run, except those which indicate problems or
errors.

-gui
Increase the frequency of pacifier messages while writing an ISO image.

-log-file disk_path
Truncate file disk_path to 0 size and redirect to it all messages which would
normally appear on stderr. -log-file with empty text as disk_path re-enables output
to stderr.

-v
Enable the output of informational program messages.

-verbose
Alias of -v.

-version
Print to standard output a text that begins with
"mkisofs 2.01-Emulation Copyright (C)"
and to standard error the version information of xorriso.

EXAMPLES

Overview of examples:
A simple image production run
Set ISO image paths by -graft-points
Perform multi-session runs
Let xorrisofs work underneath growisofs
Incremental backup of a few directory trees
Incremental backup with accumulated trees
Create bootable images for PC-BIOS and EFI

A simple image production run
A prepared file tree in directory ./for_iso gets copied into the root directory of the ISO
image. File permissions get set to read-only for everybody. Joliet attributes for
Microsoft systems get added. The resulting image gets written as data file ./image.iso on
disk.
$ xorrisofs -r -J -o ./image.iso ./for_iso

Set ISO image paths by -graft-points
Without option -graft-points each given disk file is copied into the root directory of the
ISO image, maintaining its name. If a directory is given, then its files and
sub-directories are copied into the root directory, maintaining their names.
$ xorrisofs ... /home/me/datafile /tmp/directory
yields in the ISO image root directory:
/datafile
/file_1_from_directory
...
/file_N_from_directory

With option -graft-points it is possible to put files and directories to arbitrary paths
in the ISO image.
$ xorrisofs ... -graft-points /home/me/datafile /dir=/tmp/directory
yields in the ISO image root directory:
/datafile
/dir
Eventually needed parent directories in the image will be created automatically:
/datafiles/file1=/home/me/datafile
yields in the ISO image:
/datafiles/file1
The attributes of directory /datafiles get copied from /home/me on disk.

Normally one should avoid = and \ characters in the ISO part of a pathspec. But if it
must be, one may escape them:
/with_\=_and_\\/file=/tmp/directory/file
yields in the ISO image:
/with_=_and_\/file

Perform multi-session runs
This example works for multi-session media only: CD-R[W], DVD-R[W], DVD+R, BD-R. Add
cdrskin option --grow_overwriteable_iso to all -as cdrecord runs in order to enable
multi-session emulation on overwriteable media.
The first session is written like this:
$ xorrisofs -graft-points \
/tree1=prepared_for_iso/tree1 \
| xorriso -as cdrecord -v dev=/dev/sr0 blank=fast -multi -eject -
Follow-up sessions are written like this:
$ dd if=/dev/sr0 count=1 >/dev/null 2>&1
$ m=$(xorriso -as cdrecord dev=/dev/sr0 -msinfo)
$ xorrisofs -M /dev/sr0 -C $m -graft-points \
/tree2=prepared_for_iso/tree2 \
| xorriso -as cdrecord -v dev=/dev/sr0 -waiti -multi -eject -
Always eject the drive tray between sessions. The old sessions get read via /dev/sr0. Its
device driver might not be aware of the changed content before it loads the medium again.
In this case the previous session would not be loaded and the new session would contain
only the newly added files.
For the same reason do not let xorriso -as cdrecord load the medium, but rather do this
manually or by a program that reads from /dev/sr0.

Let xorrisofs work underneath growisofs
growisofs expects an ISO formatter program which understands options -C and -M. A variable
is defined to override the hardcoded default name.
$ export MKISOFS="xorrisofs"
$ growisofs -Z /dev/dvd /some/files
$ growisofs -M /dev/dvd /more/files
If no "xorrisofs" is available on your system, then you will have to create a link
pointing to the xorriso binary and tell growisofs to use it. E.g. by:
$ ln -s $(which xorriso) "$HOME/xorrisofs"
$ export MKISOFS="$HOME/xorrisofs"
One may quit mkisofs emulation by argument "--" and make use of all xorriso commands.
growisofs dislikes options which start with "-o" but -outdev must be set to "-". So use
"outdev" instead:
$ growisofs -Z /dev/dvd --for_backup -- \
outdev - -update_r /my/files /files
$ growisofs -M /dev/dvd --for_backup -- \
outdev - -update_r /my/files /files
Note that --for_backup is given in the mkisofs emulation. To preserve the recorded extra
data it must already be in effect, when the emulation loads the image.

Incremental backup of a few directory trees
This changes the directory trees /open_source_project and /personal_mail in the ISO image
so that they become exact copies of their disk counterparts. ISO file objects get
created, deleted or get their attributes adjusted accordingly.
ACL, xattr, hard links and MD5 checksums will be recorded. It is expected that inode
numbers in the disk filesystem are persistent over cycles of mounting and booting. Files
with names matching *.o or *.swp get excluded explicitly.

To be used several times on the same medium, whenever an update of the two disk trees to
the medium is desired. Begin with a blank medium and update it until he run fails
gracefully due to lack of remaining space on the old one.
Do not let xorriso -as cdrecord load the medium, but rather do this manually or by a
program that reads from /dev/sr0.
$ dd if=/dev/sr0 count=1 >/dev/null 2>&1
$ msinfo=$(xorriso -as cdrecord dev=/dev/sr0 -msinfo)
$ load_opts=
$ test -n "$msinfo" && load_opts="-M /dev/sr0 -C $msinfo"
$ xorrisofs $load_opts -o - --for_backup -m '*.o' -m '*.swp' \
-V PROJ_MAIL_"$(date '+%Y_%m_%d_%H%M%S')" -graft-points \
-old-root / \
/projects=/home/thomas/projects \
/personal_mail=/home/thomas/personal_mail \
| xorriso -as cdrecord dev=/dev/sr0 -v -multi -waiti -eject -

This makes sense if the full backup leaves substantial remaining capacity on media and if
the expected changes are much smaller than the full backup.

Better do not use your youngest backup for -old-root. Have at least two media which you
use alternatingly. So only older backups get endangered by the new write operation, while
the newest backup is stored safely on a different medium.
Always have a blank medium ready to perform a full backup in case the update attempt fails
due to insufficient remaining capacity. This failure will not spoil the old medium, of
course.

If inode numbers on disk are not persistent, then use option --old-root-no-ino . In this
case an update run will compare recorded MD5 sums against the current file content on hard
disk.

With mount option -o "sbsector=" on GNU/Linux or -s on FreeBSD or NetBSD it is possible to
access the session trees which represent the older backup versions. With CD media,
GNU/Linux mount accepts session numbers directly by its option "session=".
Multi-session media and most overwriteable media written by xorriso can tell the sbsectors
of their sessions by xorriso option -toc:
$ xorriso -dev /dev/sr0 -toc
xorriso can print the matching mount command for a session number:
$ xorriso -mount_cmd /dev/sr0 session 12 /mnt
or for a volume id that matches a search expression:
$ xorriso -mount_cmd /dev/sr0 volid '*2008_12_05*' /mnt
Both yield on standard output something like:
mount -t iso9660 -o nodev,noexec,nosuid,ro,sbsector=1460256 '/dev/sr0' '/mnt'
The superuser may let xorriso execute the mount command directly:
# osirrox -mount /dev/sr0 "volid" '*2008_12_05*' /mnt

Incremental backup with accumulated trees
Solaris does not offer the option to mount older sessions. In order to keep them
accessible, one may map all files to a file tree under a session directory and accumulate
those directories from session to session. The -root tree is cloned from the -old-root
tree before it gets compared with the appropriate trees on disk.
This demands to know the previously used session directory name.
With the first session:
$ xorrisofs -root /session1 \
-o - --for_backup -m '*.o' -m '*.swp' \
-V PROJ_MAIL_"$(date '+%Y_%m_%d_%H%M%S')" -graft-points \
/projects=/home/thomas/projects \
/personal_mail=/home/thomas/personal_mail \
| xorriso -as cdrecord dev=/dev/sr0 -v blank=as_needed \
-multi -waiti -eject -

With the second session, option -old-root refers to /session1 and the new -root is
/session2.
Do not let xorriso -as cdrecord load the medium, but rather do this manually or by a
program that reads from /dev/sr0.
$ dd if=/dev/sr0 count=1 >/dev/null 2>&1
$ msinfo=$(xorriso -as cdrecord dev=/dev/sr0 -msinfo)
$ load_opts=
$ test -n "$msinfo" && load_opts="-M /dev/sr0 -C $msinfo"
$ xorrisofs $load_opts -root /session2 -old-root /session1 \
-o - --for_backup -m '*.o' -m '*.swp' \
-V PROJ_MAIL_"$(date '+%Y_%m_%d_%H%M%S')" -graft-points \
/projects=/home/thomas/projects \
/personal_mail=/home/thomas/personal_mail \
| xorriso -as cdrecord dev=/dev/sr0 -v -multi -waiti -eject -
With the third session, option -old-root refers to /session2. The new -root is /session3.
And so on.

Create bootable images for PC-BIOS and EFI
The SYSLINUX/ISOLINUX boot loader suite is popular for booting PC-BIOS. The ISOLINUX wiki
prescribes to create on disk a directory ./CD_root and to copy all desired files
underneath that directory. Especially file isolinux.bin shall be copied to
./CD_root/isolinux/isolinux.bin . This is the boot image file.
The prescribed mkisofs options can be used unchanged with xorrisofs:
$ xorrisofs -o output.iso \
-b isolinux/isolinux.bin -c isolinux/boot.cat \
-no-emul-boot -boot-load-size 4 -boot-info-table \
./CD_root
Put it on CD by a burn program. E.g.:
$ xorriso -as cdrecord -v dev=/dev/sr0 blank=as_needed output.iso

The image from above example will boot from CD, DVD or BD, but not from USB stick or other
hard-disk-like devices. This can be done by help of an isohybrid MBR. Syslinux provides
matching template files as isohdp[fp]x*.bin . E.g. /usr/lib/syslinux/isohdpfx.bin .
If a few hundred KB of size do not matter, then option -partition_offset can be used to
create a partition table where partition 1 starts not at block 0. This facilitates later
manipulations of the USB stick by tools for partitioning and formatting.
The image from the following example will be prepared for booting via MBR and its first
partition will start at hard disk block 64.
It will also boot from optical media.
$ xorrisofs -o output.iso \
-b isolinux/isolinux.bin -c isolinux/boot.cat \
-no-emul-boot -boot-load-size 4 -boot-info-table \
-isohybrid-mbr /usr/lib/syslinux/isohdpfx.bin \
-partition_offset 16 \
./CD_root
Become superuser and copy the image to the unpartitioned base device file of the USB
stick. On GNU/Linux this is e.g. /dev/sdb, not /dev/sdb1.
CAUTION: This will overwrite any partitioning on the USB stick and make remaining data
unaccessible.
So first make sure you got the correct address of the intended device. E.g. by reading
100 MiB data from it and watching it blinking:
# dd bs=2K if=/dev/sdb count=50K >/dev/null
Now copy the image onto it
# dd bs=2K if=output.iso of=/dev/sdb

Now for EFI:
The boot image file has to be the image of an EFI System Partition, i.e. a FAT filesystem
with directory /EFI/BOOT and boot files with EFI prescribed names: BOOTIA32.EFI for 32 bit
x86, BOOTx64.EFI for 64 bit AMD/x86 (in UEFI-2.4 there is indeed a lower case "x"),
BOOTAA64.EFI for 64 bit ARM. The software in the FAT filesystem should be able to find and
inspect the ISO filesystem for boot loader configuration and start of operating system.
GRUB2 program grub-mkimage can produce such a FAT filesystem with suitable content, which
then uses further GRUB2 software from the ISO filesystem.
EFI boot equipment may be combined with above ISOLINUX isohybrid for PC-BIOS in a not
really UEFI-2.4 compliant way, which obviously works well. It yields MBR and GPT partition
tables, both with nested partitions. Assumed the EFI System Partition image is ready as
./CD_root/boot/grub/efi.img, add the following options before the directory address
./CD_root:
-eltorito-alt-boot -e 'boot/grub/efi.img' -no-emul-boot \
-isohybrid-gpt-basdat \
More compliant with UEFI-2.4 is to decide for either MBR or GPT and to append a copy of
the EFI System Partition in order to avoid overlap of ISO partition and EFI partition.
Here for MBR:
-eltorito-alt-boot -e 'boot/grub/efi.img' -no-emul-boot \
-append_partition 2 0xef ./CD_root/boot/grub/efi.img \
The resulting ISOs are supposed to boot from optical media and USB stick. One may omit
option -eltorito-alt-boot if no option -b is used to make the ISO bootable via PC-BIOS.

For ISOs with pure GRUB2 boot equipment consider to use GRUB2 tool grub-mkrescue as
frontend to xorrisofs.

If you have a bootable ISO filesystem and want to know its equipment plus a proposal how
to reproduce it, try:
$ xorriso -hfsplus on -indev IMAGE.iso \
-report_el_torito plain -report_system_area plain \
-print "" -print "======= Proposal for xorrisofs options:" \
-report_el_torito as_mkisofs

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