Provided by: xorriso_1.5.2-1_amd64 bug


       xorriso  -  creates,  loads,  manipulates  and writes ISO 9660 filesystem images with Rock
       Ridge extensions.


       xorriso [settings|actions]


       xorriso is a program which copies file objects from POSIX compliant filesystems into  Rock
       Ridge  enhanced  ISO  9660  filesystems  and  performs  session-wise  manipulation of such
       filesystems. It can load the management information of existing ISO images and  it  writes
       the session results to optical media or to filesystem objects.
       Vice versa xorriso is able to copy file objects out of ISO 9660 filesystems.

       A  special  property  of  xorriso  is that it needs neither an external ISO 9660 formatter
       program nor an external burn program for  CD,  DVD  or  BD  but  rather  incorporates  the
       libraries of .

   Overview of features:
       Operates on an existing ISO image or creates a new one.
       Copies files from disk filesystem into the ISO image.
       Copies files from ISO image to disk filesystem (see osirrox).
       Renames or deletes file objects in the ISO image.
       Changes file properties in the ISO image.
       Updates ISO subtrees incrementally to match given disk subtrees.
       Writes  result  either  as  completely  new image or as add-on session to optical media or
       filesystem objects.
       Can activate ISOLINUX and GRUB boot images via El Torito and MBR.
       Can perform multi-session tasks as emulation of mkisofs and cdrecord.
       Can record and restore hard links and ACL.
       Content may get zisofs compressed or filtered by external processes.
       Can issue commands to mount older sessions on GNU/Linux or FreeBSD.
       Can check media for damages and copy readable blocks to disk.
       Can attach MD5 checksums to each data file and the whole session.
       Scans for optical drives, blanks re-useable optical media.
       Reads its instructions from command line arguments, dialog, and files.
       Provides navigation commands for interactive ISO image manipulation.
       Adjustable thresholds for abort, exit value, and problem reporting.

       Note that xorriso does not write audio CDs and that it does not  produce  UDF  filesystems
       which are specified for official video DVD or BD.

   General information paragraphs:
       Session model
       Media types and states
       Creating, Growing, Modifying, Blind Growing
       Libburn drives
       Rock Ridge, POSIX, X/Open, El Torito, ACL, xattr
       Command processing
       Dialog, Readline, Result pager

       Maybe  you  first want to have a look at section EXAMPLES near the end of this text before
       reading the next few hundred lines of background information.

   Session model:
       Unlike other filesystems, ISO 9660 (aka ECMA-119) is not intended for read-write operation
       but rather for being generated in a single sweep and being written to media as a session.
       The data content of the session is called filesystem image.

       The  written  image  in  its session can then be mounted by the operating system for being
       used read-only. GNU/Linux is able to mount  ISO  images  from  block  devices,  which  may
       represent  optical  media,  other media or via a loop device even from regular disk files.
       FreeBSD mounts ISO images from devices that represent arbitrary media or from regular disk

       This  session  usage model has been extended on CD media by the concept of multi-session ,
       which adds information to the CD and gives the mount programs of the operating systems the
       addresses  of the entry points of each session. The mount programs recognize block devices
       which represent CD media and will by default mount the image in the last session.
       This session usually contains an updated directory tree for the whole medium which governs
       the  data  contents  in  all  recorded  sessions.  So in the view of the mount program all
       sessions of a particular medium together form a single filesystem image.
       Adding a session to an existing ISO image is in this text referred as growing.
       The multi-session model of the MMC standard does not apply to all media types. But program
       growisofs  by Andy Polyakov showed how to extend this functionality to overwriteable media
       or disk files which carry valid ISO 9660 filesystems.

       xorriso provides growing as well as  an  own  method  named  modifying  which  produces  a
       completely  new ISO image from the old one and the modifications.  See paragraph Creating,
       Growing, Modifying, Blind Growing below.

       xorriso adopts the concept of multi-session by loading an image directory tree if present,
       by  offering  to  manipulate  it  by  several actions, and by writing the new image to the
       target medium.
       The first session of a xorriso run begins by the definition of the input  drive  with  the
       ISO  image  or  by the definition of an output drive.  The session ends by command -commit
       which triggers writing. A -commit is done automatically when the program ends regularly.

       After -commit a new session begins with the freshly written one as  input.   A  new  input
       drive  can  only  be  chosen  as  long  as  the  loaded ISO image was not altered. Pending
       alteration can be revoked by command -rollback.

       Writing a session to the target is supposed to be very expensive in terms of time  and  of
       consumed  space on appendable or write-once media. Therefore all intended manipulations of
       a particular ISO image should be done in a single session. But in principle it is possible
       to store intermediate states and to continue with image manipulations.

   Media types and states:
       There are two families of media in the MMC standard:
       Multi-session media are CD-R, CD-RW, DVD-R, DVD+R, DVD+R/DL, BD-R, and unformatted DVD-RW.
       These media provide a table of  content  which  describes  their  existing  sessions.  See
       command -toc.
       Similar  to  multi-session  media  are DVD-R DL and minimally blanked DVD-RW.  They record
       only a single session of which the size must be known in advance.  xorriso will write onto
       them only if command -close is set to "on".
       Overwriteable  media  are DVD-RAM, DVD+RW, BD-RE, and formatted DVD-RW.  They offer random
       write access but do not provide information about their session history. If  they  contain
       one  or  more  ISO  9660  sessions and if the first session was written by xorriso, then a
       table of content can be emulated. Else only a single overall session will be visible.
       DVD-RW media can be formatted by -format "full".  They can be made unformatted  by  -blank
       Regular  files  and  block  devices  are  handled as overwriteable media.  Pipes and other
       writeable file types are handled as blank multi-session media.

       These media can assume several states in which they offer different capabilities.
       Blank media can be written from scratch. They contain no ISO image suitable for xorriso.
       Blank is the state of newly purchased optical media.  With used CD-RW and DVD-RW it can be
       achieved  by  action -blank "as_needed".  Overwriteable media are considered blank if they
       are new or if they have been marked as blank by xorriso.  Action -blank "as_needed" can be
       used  to  do  this marking on overwriteable media, or to apply mandatory formatting to new
       media if necessary.
       Appendable media accept further sessions. Either  they  are  MMC  multi-session  media  in
       appendable  state, or they are overwriteable media which contain an ISO image suitable for
       Appendable is the state after writing a session with command -close off.
       Closed media cannot be written. They may contain an ISO image suitable for xorriso.
       Closed is the state of DVD-ROM media and of multi-session media which  were  written  with
       command -close on. If the drive is read-only hardware then it will probably show any media
       as closed CD-ROM or DVD-ROM.
       Overwriteable media assume this  state  in  such  read-only  drives  or  if  they  contain
       unrecognizable data in the first 32 data blocks.
       Read-only  drives may or may not show session histories of multi-session media. Often only
       the first and the last session are visible. Sometimes not even that. Command -rom_toc_scan
       might or might not help in such cases.

   Creating, Growing, Modifying, Blind Growing:
       A  new empty ISO image gets created if there is no input drive with a valid ISO 9660 image
       when the first time an output drive is defined. This is achieved by command -dev on  blank
       media or by command -outdev on media in any state.
       The  new  empty  image  can  be  populated  with  directories and files.  Before it can be
       written, the medium in the output drive must get into blank state  if  it  was  not  blank

       If  there  is  a  input  drive  with  a  valid  ISO  image, then this image gets loaded as
       foundation for manipulations and extension. The constellation of input  and  output  drive
       determines  which  write  method will be used.  They have quite different capabilities and

       The method of growing adds new data to  the  existing  data  on  the  medium.  These  data
       comprise  of  new  file  content  and  they  override  the  existing ISO 9660 + Rock Ridge
       directory tree. It is possible to hide files from previous sessions but they  still  exist
       on  the  medium  and  with many types of optical media it is quite easy to recover them by
       mounting older sessions.
       Growing is achieved by command -dev.

       The write method of modifying produces compact filesystem images with no outdated files or
       directory  trees.  Modifying  can  write  its  images to target media which are completely
       unsuitable for multi-session operations.  E.g.  DVD-RW  which  were  treated  with  -blank
       deformat_quickest,  DVD-R  DL, named pipes, character devices, sockets.  On the other hand
       modified sessions cannot be written to appendable media but to blank media only.
       So for this method one needs either two optical drives or  has  to  work  with  filesystem
       objects as source and/or target medium.
       Modifying  takes  place  if  input  drive and output drive are not the same and if command
       -grow_blindly is set to its default "off".   This  is  achieved  by  commands  -indev  and

       If  command  -grow_blindly  is  set to a non-negative number and if -indev and -outdev are
       both set to different drives, then blind growing  is  performed.  It  produces  an  add-on
       session  which  is  ready  for being written to the given block address. This is the usage
       model of
        mkisofs -M $indev -C $msc1,$msc2 -o $outdev
       which gives much room for wrong parameter combinations and should thus only be employed if
       a  strict  distinction  between  ISO formatter xorriso and the burn program is desired. -C
       $msc1,$msc2 is equivalent to:
        -load sbsector $msc1 -grow_blindly $msc2

   Libburn drives:
       Input drive, i.e. source of an existing or empty ISO  image,  can  be  any  random  access
       readable  libburn  drive:  optical  media with readable data, blank optical media, regular
       files, block devices.
       Output drive, i.e. target for writing, can be any libburn drive.  Some drive types do  not
       support  the  method  of growing but only the methods of modifying and blind growing. They
       all are suitable for newly created images.

       All drive file objects have to offer rw-permission to the user  of  xorriso.   Even  those
       which will not be useable for reading an ISO image.
       With any type of drive object, the data are considered to be organized in blocks of 2 KiB.
       Access happens in terms of Logical Block  Address  (LBA)  which  gives  the  number  of  a
       particular data block.

       MMC  compliant  (i.e.  optical)  drives  on GNU/Linux usually get addressed by the path of
       their block device or of their generic character device. E.g.
         -dev /dev/sr0
         -dev /dev/hdc
         -dev /dev/sg2
       By default xorriso will try to map the  given  address  to  /dev/hd*  and  /dev/sr*.   The
       command  -scsi_dev_family  can redirect the mapping from sr to scd or sg.  The latter does
       not suffer from the concurrency problems which  plague  /dev/sr  of  Linux  kernels  since
       version  3.  But  it  does  not  yield the same addresses which are used by mount(8) or by
       open(2) for read(2).
       On FreeBSD the device files have names like
         -dev /dev/cd0
       On NetBSD:
         -dev /dev/rcd0d
       On OpenSolaris:
         -dev /dev/rdsk/c4t0d0s2
       Get a list of accessible drives by command
       It might be necessary to do this as superuser in order to see all drives and to then allow
       rw-access for the intended users.  Consider to bundle the authorized users in a group like
       old "floppy".

       Filesystem objects of nearly any type can be addressed by prefix "stdio:" and  their  path
       in the filesystem. E.g.:
         -dev stdio:/dev/sdc
       The default setting of -drive_class allows the user to address files outside the /dev tree
       without that prefix. E.g.:
         -dev /tmp/pseudo_drive
       If path leads to a regular file or to a block device then the  emulated  drive  is  random
       access  readable  and can be used for the method of growing if it already contains a valid
       ISO 9660 image. Any other file type is not readable via "stdio:" and can only be  used  as
       target  for  the  method  of  modifying  or blind growing.  Non-existing paths in existing
       directories are handled as empty regular files.

       A very special kind of pseudo drive are  open  file  descriptors.  They  are  depicted  by
       "stdio:/dev/fd/" and descriptor number (see man 2 open).
       Addresses  "-"  or  "stdio:/dev/fd/1" depict standard output, which normally is the output
       channel for result texts.  To  prevent  a  fatal  intermingling  of  ISO  image  and  text
       messages,  all  result texts get redirected to stderr if -*dev "-" or "stdio:/dev/fd/1" is
       among the start arguments of the program.
       Standard output is currently suitable for creating one session  per  program  run  without
       dialog. Use in other situations is discouraged and several restrictions apply:
       It  is  not  allowed  to use standard output as pseudo drive if it was not among the start
       arguments. Do not try to fool this ban via backdoor addresses to stdout.
       If stdout is used as drive, then -use_readline is permanently disabled.  Use of  backdoors
       can cause severe memory and/or tty corruption.

       Be  aware  that  especially  the superuser can write into any accessible file or device by
       using its path with the "stdio:" prefix. By default any address in the /dev  tree  without
       prefix "stdio:" will work only if it leads to a MMC drive.
       One  may  use  command  -ban_stdio_write to surely prevent this risk and to restrict drive
       usage to MMC drives.
       One may prepend "mmc:" to a path to surely disallow any automatic "stdio:".
       By command -drive_class one may ban certain paths or allow access without prefix  "stdio:"
       to other paths.

   Rock Ridge, POSIX, X/Open, El Torito, ACL, xattr:
       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.
       This  is  what  xorriso  uses for a decent representation of the disk files within the ISO
       image. xorriso produces Rock Ridge information by default. It is strongly  discouraged  to
       disable this feature.

       xorriso  is  not  named  "porriso" because POSIX only guarantees 14 characters of filename
       length. It is the X/Open System Interface standard XSI which demands a file name length of
       up to 255 characters and paths of up to 1024 characters. Rock Ridge fulfills this demand.

       An  El  Torito  boot  record  points  the  BIOS bootstrapping facility to 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.
       Most  bootable  GNU/Linux  CDs are equipped with ISOLINUX or GRUB boot images.  xorriso is
       able to create or maintain an El Torito object which makes such  an  image  bootable.  For
       details see command -boot_image.
       It  is  possible to make ISO images bootable from USB stick or other hard-disk-like media.
       Several options install a MBR (Master Boot Record), It may get adjusted according  to  the
       needs of the intended boot firmware and the involved boot loaders, e.g. GRUB2 or ISOLINUX.
       A MBR contains boot code and a partition table.  The new MBR of a  follow-up  session  can
       get in effect only on overwriteable media.
       MBR  is  read  by PC-BIOS when booting from USB stick or hard disk, and by PowerPC CHRP or
       PReP when booting.  An MBR partition with type 0xee indicates the presence of GPT.
       Emulation -as mkisofs 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.
       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.
       There  is support for further facilities: MIPS Big Endian (SGI), MIPS Little Endian (DEC),
       SUN SPARC, HP-PA.  Those are mutually not combinable and also  not  combinable  with  MBR,
       GPT, or APM.

       ACL  are  an  advanced  way of controlling access permissions to file objects. Neither ISO
       9660 nor Rock Ridge specify a way to record ACLs. So libisofs has  introduced  a  standard
       conformant  extension  named  AAIP for that purpose.  It uses this extension if enabled by
       command -acl.
       AAIP enhanced images are supposed to be mountable normally, but one cannot expect that the
       mounted  filesystem  will  show  and  respect  the ACLs.  For now, only xorriso is able to
       retrieve those ACLs.  It can bring them into effect when files  get  restored  to  an  ACL
       enabled file system or it can print them in a format suitable for tool setfacl.
       Files  with  ACL  show  as  group  permissions the setting of entry "mask::" if that entry
       exists.  Nevertheless  the  non-listed  group  members  get  handled  according  to  entry
       "group::". When removing ACL from a file, xorriso brings "group::" into effect.
       Recording  and restoring of ACLs from and to local files works currently only on GNU/Linux
       and FreeBSD.

       xattr (aka EA, or extattr) are pairs of name and value  which  can  be  attached  to  file
       objects. AAIP is able to represent them and xorriso can record and restore them.
       But  be  aware  that  pairs with names of non-user namespaces are not necessarily portable
       between operating systems and not even between filesystems.  Only those which  begin  with
       "user.",  like  "user.x"  or  "user.whatever",  can  unconditionally  be  expected  to  be
       appropriate on other machines and disks.  Processing of other xattr may need administrator
       Name  has  to  be  a  0 terminated string.  Value may be any array of bytes which does not
       exceed the size of 4095 bytes.  xattr processing happens only if it is enabled by  command
       As  with  ACL, currently only xorriso is able to retrieve xattr from AAIP enhanced images,
       to restore them to xattr capable file systems, or to print them.
       Recording and restoring of xattr from and to local files works currently only on GNU/Linux
       and FreeBSD, where they are known as extattr.

   Command processing:
       Commands are either actions which happen immediately or settings which influence following
       actions. So their sequence does matter, unless they are given  as  program  arguments  and
       command -x is among them.
       Commands  consist of a command word, followed by zero or more parameter words. If the list
       of parameter words is of variable length (indicated by "[...]" or "[***]") then it must be
       terminated  by  either the list delimiter, occur at the end of the argument list, or occur
       at the end of an input line.

       At program start the list delimiter is the string "--".  This  may  be  changed  with  the
       -list_delimiter  command  in  order  to allow "--" as parameter in a variable length list.
       However, it is advised to reset the delimiter to "--" immediately afterwards.
       For brevity the list delimiter is referred as "--" throughout this text.
       The list delimiter is silently ignored if it appears after the  parameters  of  a  command
       with  a fixed list length. It is handled as normal text if it appears among the parameters
       of such a command.

       Pattern expansion converts a list of pattern words into a list of existing file addresses.
       Unmatched pattern words will appear unaltered in that result list.
       Pattern  matching  supports  the usual shell parser wildcards '*' '?' '[xyz]' and respects
       '/' as the path separator, which may only be matched literally.
       Pattern expansion is a property of some particular commands and not a general feature.  It
       is  controlled  by commands -iso_rr_pattern and -disk_pattern.  Commands which use pattern
       expansion all have variable parameter lists which are specified in this  text  by  "[***]"
       rather than "[...]".
       Some other commands perform pattern matching unconditionally.

       Command and parameter words are either read from the program arguments, where one argument
       is one word, or from quoted  input  lines  where  words  are  recognized  similar  to  the
       quotation rules of a shell parser.
       xorriso  is  not a shell, although it might appear so at first glimpse.  Be aware that the
       interaction of quotation marks and pattern symbols like "*" differs from the  usual  shell
       parsers. In xorriso, a quotation mark does not make a pattern symbol literal.

       Quoted  input  converts whitespace-separated text into words.  The double quotation mark "
       and the single quotation mark ' can be used to enclose whitespace  and  make  it  part  of
       words  (e.g.  of  file  names).  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.
       Quoted  input  accepts  any  8-bit  character except NUL (0) as the content of the quotes.
       Nevertheless it can be cumbersome for the  user  to  produce  those  characters  directly.
       Therefore quoted input and program arguments offer optional Backslash Interpretation which
       can represent all 8-bit characters except NUL (0) via backslash  codes  as  in  $'...'  of
       This is not enabled by default. See command -backslash_codes.

       When  the  program  starts then it first looks for argument -no_rc. If this is not present
       then it looks for its startup files and reads their content as command input  lines.  Then
       it  interprets  the program arguments as commands and parameters. Finally it enters dialog
       mode if command -dialog "on" has been executed by this point.

       The program ends either by command -end, or by the end of program arguments if dialog mode
       has  not been enabled at that point, or by a problem event which triggers the threshold of
       command -abort_on.

   Dialog, Readline, Result pager:
       Dialog mode prompts for a quoted input line, parses it into words, and  performs  them  as
       commands  with  their  parameters.  It  provides  assisting  services  to make dialog more

       Readline is an enhancement for the input line. You may  already  know  it  from  the  bash
       shell.  Whether  it  is  available  in  xorriso  depends  on  the  availability of package
       readline-dev at the time when xorriso was built from its sourcecode.
       Readline lets the user move the cursor over the text in the line by help of the  Left  and
       the Right arrow keys.  Text may be inserted at the cursor position. The Delete key removes
       the character under the cursor. Up and Down arrow keys navigate  through  the  history  of
       previous input lines.
       See man readline for more info about libreadline.

       Command  -page  activates  a  built-in result text pager which may be convenient in dialog
       mode. After an action has output the given number of terminal lines, the pager prompts the
       user for a line of input.
       An empty line lets xorriso resume work until the next page is output.
       The single character "@" disables paging for the current action.
       "@@@",  "x",  "q", "X", or "Q" request that the current action aborts and suppress further
       result output.
       Any other line input will be interpreted  as  new  dialog  line.  The  current  action  is
       requested to abort. Afterwards, the input line is executed.

       Some actions apply paging to their info output, too.
       The  request  to abort may or may not be obeyed by the current action.  All actions try to
       abort as soon as possible.


       All command words are shown with a leading dash although this dash is  not  mandatory  for
       the  command  to be recognized. Nevertheless within command -as the dashes of the emulated
       commands are mandatory.
       Normally any number of leading dashes is ignored with command words and inner  dashes  are
       interpreted as underscores.

       Execution order of program arguments:

       By  default  the  program  arguments  of  a  xorriso  run are interpreted as a sequence of
       commands which get performed exactly in the given order.  This requires the user to  write
       commands  for  desired  settings  before  the  commands which shall be influenced by those
       Many other programs support  program  arguments  in  an  arbitrary  ordering  and  perform
       settings and actions in a sequence at their own discretion.  xorriso provides an option to
       enable such a behavior at the cost of loss of expressivity.

       -x     Enable automatic sorting of program arguments into a sequence that (most likely) is
              sensible.   This  command may be given at any position among the commands which are
              handed over as program arguments.
              Note: It works only if it is given as program argument and with a single dash (i.e.
              "-x").  It  will  not  work  in  startup files, nor with -options_from_file, nor in
              dialog mode, nor as "x" and finally not as "--x".  It  affects  only  the  commands
              given as program arguments.

              List all xorriso commands in the order which applies if command -x is in effect.
              This  list  may also be helpful without -x for a user who ponders over the sequence
              in which to put commands. Deviations from the listed sorting order  may  well  make
              sense, though.

       Acquiring source and target drive:

       The  effect  of  acquiring  a  drive  may depend on several commands in the next paragraph
       "Influencing the behavior of image loading".  If desired, their enabling commands have  to
       be performed before the commands which acquire the drive.

       -dev address
              Set  input  and  output  drive  to  the same address and load an ISO image if it is
              present.  If there is no ISO  image  then  create  a  blank  one.   Set  the  image
              expansion method to growing.
              This  is only allowed as long as no changes are pending in the currently loaded ISO
              image. If changes are pending, then one has to perform -commit or -rollback first.
              Special address string "-" means standard output,  to  which  several  restrictions
              apply. See above paragraph "Libburn drives".
              An empty address string "" gives up the current device without acquiring a new one.

       -indev address
              Set  input  drive and load an ISO image if present.  If the new input drive differs
              from -outdev then switch from growing to modifying or to blind growing.  It depends
              on  the  setting of -grow_blindly which of both gets activated.  The same rules and
              restrictions apply as with -dev.

       -outdev address
              Set output drive and if it differs from the input drive then switch from growing to
              modifying  or  to blind growing. Unlike -dev and -indev this action does not load a
              new ISO image. So it can be performed even if there are pending changes.
              -outdev can be performed without previous -dev or -indev. In that case an empty ISO
              image  with  no  changes  pending is created. It can either be populated by help of
              -map, -add or it can be discarded silently if -dev or -indev  are  performed
              Special  address  string  "-"  means standard output, to which several restrictions
              apply. See above paragraph "Libburn drives".
              An empty address string "" gives up the current output drive  without  acquiring  a
              new one. No writing is possible without an output drive.

       -drive_class "harmless"|"banned"|"caution"|"clear_list" disk_pattern
              Add  a  drive  path  pattern  to one of the safety lists or make those lists empty.
              There are three lists defined which get tested in the following sequence:
              If a drive address path  matches  the  "harmless"  list  then  the  drive  will  be
              accepted.  If  it  is  not  a MMC device then the prefix "stdio:" will be prepended
              automatically. This list is empty by default.
              Else if the path matches the "banned" list then the drive will not be  accepted  by
              xorriso but rather lead to a FAILURE event.  This list is empty by default.
              Else if the path matches the "caution" list and if it is not a MMC device, then its
              address must have the prefix "stdio:" or it will be rejected.   This  list  has  by
              default one entry: "/dev".
              If  a drive path matches no list then it is considered "harmless". By default these
              are all paths which do not begin with directory "/dev".
              A path matches a list if one of its parent paths or itself matches  a  list  entry.
              Address prefix "stdio:" or "mmc:" will be ignored when testing for matches.
              By  pseudo-class  "clear_list" and pseudo-patterns "banned", "caution", "harmless",
              or "all", the lists may be made empty.
              E.g.: -drive_class clear_list banned
              One will normally define the -drive_class lists  in  one  of  the  xorriso  Startup
              Note:  This  is  not  a  security  feature but rather a bumper for the superuser to
              prevent inadverted mishaps. For reliably blocking access to a device file you  have
              to deny its rw-permissions in the filesystem.

       -drive_access "exclusive"|"shared":"unrestricted"|"readonly"
              Control  whether  device  file  locking  mechanisms  shall be used when acquiring a
              drive, and whether status or content of the medium in the  drive  may  be  altered.
              Useful  and most harmless are the setting "shared:readonly" and the default setting
              "exclusive" enables tests and locks when acquiring the drive.  It  depends  on  the
              operating  system  which locking mechanisms get applied, if any. On GNU/Linux it is
              open(O_EXCL). On FreeBSD it is flock(LOCK_EX).
              "shared" disables the use of these mechanisms to  become  able  to  acquire  drives
              which are mounted, or opened by some process, or guarded by /dev/pktcdvd*.
              "unrestricted" enables all technically appropriate operations on an acquired drive.
              "shared:unrestricted" risks to get own burn runs spoiled by other processes  or  to
              vice  versa  spoil  activities  of  such processes. So use "exclusive:unrestricted"
              unless you know for sure that "shared" is safe.
              "readonly" disables operations which might surprise a co-user of  the  drive.   For
              -outdev  these  are  formatting,  blanking,  writing,  ejecting. For -indev this is
              ejecting. Be aware that even reading and drive  status  inquiries  can  disturb  an
              ongoing burn run on CD-R[W] and DVD-R[W].

       -scsi_dev_family "default"|"sr"|"scd"|"sg"
              GNU/Linux specific:
              By  default, xorriso tries to map Linux drive addresses to /dev/sr* before they get
              opened for operating the drive. This coordinates  well  with  other  use  cases  of
              optical drives, like mount(8). But since year 2010 all /dev/sr* share a global lock
              which allows only one drive to process an SCSI command while  all  others  have  to
              wait  for  its  completion.  This yields awful throughput if more than one drive is
              writing or reading simultaneously.  The global lock is not applied to device  files
              /dev/sg* and also not if the xorriso drive address is prepended by "stdio:".
              So  for  simultaneous  burn  runs  on  modern  GNU/Linux it is advisable to perform
              -scsi_dev_family "sg" before any -dev, -indev, or -outdev. The drive addresses  may
              then  well  be  given  as  /dev/sr*  but will nevertheless get used as the matching
              If you decide so, consider to put the command  into  a  global  startup  file  like

       -grow_blindly "off"|predicted_nwa
              If  predicted_nwa  is  a non-negative number then perform blind growing rather than
              modifying if -indev and -outdev are set to different drives.  "off" or "-1"  switch
              to modifying, which is the default.
              predicted_nwa  is  the block address where the add-on session of blind growing will
              finally end up. It is the responsibility of the user to ensure this final  position
              and  the  presence  of  the  older sessions. Else the overall ISO image will not be
              mountable or will produce read errors when accessing  file  content.  xorriso  will
              write  the  session  to  the  address  as  obtained  from examining -outdev and not
              necessarily to predicted_nwa.
              During a run of blind growing, the input drive is given up  before  output  begins.
              The output drive is given up when writing is done.

       Influencing the behavior of image loading:

       The  following  commands should normally be performed before loading an image by acquiring
       an input drive. In rare cases it is desirable to activate them only after image loading.

       -read_speed code|number[k|m|c|d|b]
              Set the speed for reading. Default is "none", which avoids to send a speed  setting
              command to the drive before reading begins.
              Further special speed codes are:
              "max" (or "0") selects maximum speed as announced by the drive.
              "min" (or "-1") selects minimum speed as announced by the drive.
              Speed can be given in media dependent numbers or as a desired throughput per second
              in MMC compliant kB (= 1000) or MB (= 1000 kB). Media x-speed  factor  can  be  set
              explicitly by "c" for CD, "d" for DVD, "b" for BD, "x" is optional.
              Example speeds:
               706k = 706kB/s = 4c = 4xCD
               5540k = 5540kB/s = 4d = 4xDVD
              If  there  is  no hint about the speed unit attached, then the medium in the -indev
              will decide. Default unit is CD = 176.4k.
              Depending on the drive, the reported read speeds can be deceivingly  low  or  high.
              Therefore  "min"  cannot  become  higher than 1x speed of the involved medium type.
              Read speed "max" cannot become lower than 52xCD, 24xDVD, or 20xBD, depending on the
              medium type.
              MMC  drives usually activate their own idea of speed and take the speed value given
              by the burn program only as hint for their own decision.

       -load entity id
              Load a particular (possibly outdated) ISO session from -dev or -indev.  Usually all
              available sessions are shown with command -toc.
              entity  depicts  the  kind  of  addressing.  id depicts the particular address. The
              following entities are defined:
              "auto" with any id addresses the last session in -toc. This is the default.
              "session" with id being a number as of a line "ISO session", column "Idx".
              "track" with id being a number as of a line "ISO track", column "Idx".
              "lba" or "sbsector" with a number as of a line "ISO ...", column "sbsector".
              "volid" with a search pattern for a text as of a line  "ISO  ...",  column  "Volume
              Addressing  a non-existing entity or one which does not represent an ISO image will
              either abandon -indev or at least lead to a blank image.
              If an input drive is set at the moment when -load is executed, then  the  addressed
              ISO  image  is loaded immediately. Else, the setting will be pending until the next
              -dev or -indev. After the image has been loaded once,  the  setting  is  valid  for
              -rollback until next -dev or -indev, where it will be reset to "auto".

       -displacement [-]lba
              Compensate a displacement of the image versus the start address for which the image
              was prepared. This affects only loading of ISO images and reading of  their  files.
              The  multi-session  method  of  growing  is not allowed as long as -displacement is
              non-zero. I.e. -indev and -outdev must be different. The displacement gets reset to
              0 before the drive gets re-acquired after writing.
              If  a  track of a CD starts at block 123456 and gets copied to a disk file where it
              begins at block 0, then this copy can be loaded with
                -displacement -123456
              If an ISO image was written onto a partition with offset of 640000  blocks  of  512
              bytes, then it can be loaded from the base device by
                -load sbsector 160000 -displacement 160000
              (If the partition start address is not divisible by 4, then you will have to employ
              a loop device instead.)
              In both cases, the ISO sessions should be self contained, i.e. not add-on  sessions
              to an ISO image outside their track or partition.

       -read_fs "any"|"norock"|"nojoliet"|"ecma119"
              Specify  which  kind  of  filesystem tree to load if present. If the wish cannot be
              fulfilled, then ECMA-119 names are loaded and converted according to -ecma119_map.
              "any" first tries to read Rock Ridge. If not present, Joliet is tried.
              "norock" does not try Rock Ridge.
              "nojoliet" does not try Joliet.
              "ecma119" tries neither Rock Ridge nor Joliet.

       -assert_volid pattern severity
              Refuse to load ISO images with volume IDs which  do  not  match  the  given  search
              pattern.  When refusing an image, give up the input drive and issue an event of the
              given severity (like FAILURE, see -abort_on). An empty search pattern  accepts  any
              This  command does not hamper the creation of an empty image from blank input media
              and does not discard an already loaded image.

       -in_charset character_set_name
              Set the character set from which to convert file names when loading an  image.  See
              paragraph  "Character  sets" for more explanations.  When loading the written image
              after -commit the setting of -out_charset will be copied to -in_charset.

       -auto_charset "on"|"off"
              Enable or disable recording and interpretation of the output character set name  in
              an  xattr  attribute  of  the  image  root  directory. If enabled and if a recorded
              character set name is found, then this name will be  used  as  name  of  the  input
              character set when reading an image.
              Note  that  the  default  output charset is the local character set of the terminal
              where xorriso runs. Before attributing this local character set to the produced ISO
              image,  check  whether  the  terminal  properly  displays  all  intended filenames,
              especially exotic national characters.

       -hardlinks mode[:mode...]
              Enable or disable loading and recording of hardlink relations.
              In default mode "off", iso_rr files lose their inode numbers at  image  load  time.
              Each iso_rr file object which has no inode number at image generation time will get
              a new unique inode number if -compliance is set to new_rr.
              Mode "on" preserves inode numbers from  the  loaded  image  if  such  numbers  were
              recorded.  When committing a session it searches for families of iso_rr files which
              stem from the same disk file, have identical content filtering and  have  identical
              properties.  The  family  members  all  get  the  same inode number.  Whether these
              numbers are respected at mount time depends on the operating system.
              Command -lsl displays hardlink counts if "lsl_count" is enabled. This can slow down
              the  command substantially after changes to the ISO image have been made. Therefore
              the default is "no_lsl_count".
              Commands  -update  and  -update_r  track  splits  and  fusions  of  hard  links  in
              filesystems  which  have  stable device and inode numbers. This can cause automatic
              last  minute  changes  before  the  session  gets   written.   Command   -hardlinks
              "perform_update" may be used to do these changes earlier, e.g. if you need to apply
              filters to all updated files.
              Mode "without_update" avoids hardlink processing during update commands.  Use  this
              if your filesystem situation does not allow -disk_dev_ino "on".
              xorriso  commands  which extract files from an ISO image try to hardlink files with
              identical inode number. The normal scope of this operation is from  image  load  to
              image  load.  One  may  give  up  the accumulated hard link addresses by -hardlinks
              A large number of hardlink families may exhaust  -temp_mem_limit  if  not  -osirrox
              "sort_lba_on"  and  -hardlinks  "cheap_sorted_extract"  are  both  in  effect. This
              restricts hard linking to other files restored by the same single extract  command.
              -hardlinks "normal_extract" re-enables wide and expensive hardlink accumulation.

       -acl "on"|"off"
              Enable  or  disable  processing of ACLs.  If enabled, then xorriso will obtain ACLs
              from disk file objects, store ACLs in the ISO image  using  the  libisofs  specific
              AAIP  format,  load AAIP data from ISO images, test ACL during file comparison, and
              restore ACLs to disk files when extracting them from ISO images.  See also commands
              -getfacl, -setfacl.

       -xattr "on"|"user"|"any"|"off"
              Enable  or  disable  processing of xattr attributes.  If enabled, then xorriso will
              handle xattr similar to ACL.  See also  commands  -getfattr,  -setfattr  and  above
              paragraph about xattr.
              Modes "on" and "user" read and write only attributes from namespace "user".
              Mode  "any"  processes  attributes of all namespaces. This might need administrator
              privileges, even if the owner  of  the  disk  file  tries  to  read  or  write  the
              Note  that  xattr  from  namespace "isofs." are never read from disk or restored to
              disk. Further it is not  possible  to  set  them  via  xorriso  xattr  manipulation

       -md5 "on"|"all"|"off"|"load_check_off"
              Enable  or disable processing of MD5 checksums for the overall session and for each
              single data file. If enabled then images with checksum tags get loaded only if  the
              tags  of  superblock  and  directory tree match properly. The MD5 checksums of data
              files and whole session get loaded from the image if there are any.
              With commands -compare and -update the recorded MD5 of a file will be used to avoid
              content  reading  from  the  image.  Only  the  disk  file content will be read and
              compared with that MD5. This can save  much  time  if  -disk_dev_ino  "on"  is  not
              At  image  generation  time  they  are  computed  for each file which gets its data
              written into the new session. The checksums of files which have their data in older
              sessions  get copied into the new session. Superblock, tree and whole session get a
              checksum tag each.
              Mode "all" will additionally check during image generation whether the checksum  of
              a  data  file  changed between the time when its reading began and the time when it
              ended. This implies reading every file twice.
              Mode "load_check_off" together with "on" or "all" will load recorded MD5  sums  but
              not  test  the  recorded  checksum  tags of superblock and directory tree.  This is
              necessary if growisofs was used as burn program, because it does not overwrite  the
              superblock  checksum  tag  of  the  first  session.  Therefore load_check_off is in
              effect when xorriso -as mkisofs option -M is performed.
              The test can be re-enabled by mode "load_check_on".
              Checksums can be exploited via commands -check_md5, -check_md5_r, via find  actions
              get_md5, check_md5, and via -check_media.

              Enable  all extra features which help to produce or to restore backups with highest
              fidelity of file properties. Currently this is a shortcut for:
              -hardlinks on -acl on -xattr any -md5 on
              If you restore a backup with xattr from non-user namespaces, then  make  sure  that
              the  target  operating  system  and  filesystem  know  what  these attributes mean.
              Possibly  you  will  need  administrator  privileges  to  record  or  restore  such
              attributes.  At recording time, xorriso will try to tolerate missing privileges and
              just record what is readable.  But at restore time, missing privileges  will  cause
              failure events.
              Command  -xattr  "user" after command -for_backup excludes non-user attributes from
              being recorded or restored.

       -ecma119_map "stripped"|"unmapped"|"lowercase"|"uppercase"
              Choose the conversion of file names from the loaded session if neither a Rock Ridge
              name nor a Joliet name was read from the session.
              Mode  "stripped" is the default. It shows the names as found in the ISO but removes
              trailing ";1" or ".;1" if present.
              Mode "unmapped" shows names as found without removing characters.
              Mode "lowercase" is like "stripped" but also maps uppercase  letters  to  lowercase
              letters. This is compatible to default GNU/Linux mount behavior.
              Mode "uppercase" is like "stripped" but maps lowercase letters to uppercase, if any
              occur despite the prescriptions of ECMA-119.

       -iso_nowtime "dynamic"|timestring
              Choose whether to use the current time  ("dynamic")  or  a  fixed  time  point  for
              timestamps  of  ISO  9660  nodes  without  a  disk  source  file and as default for
              superblock timestamps.
              If a timestring is given, then it is used for such timestamps. For the  formats  of
              timestrings see command -alter_date.

       -disk_dev_ino "on"|"ino_only"|"off"
              Enable  or  disable  processing  of recorded file identification numbers (dev_t and
              ino_t). If enabled they are stored as xattr and can substantially  accelerate  file
              comparison.  The  root  node  gets a global start timestamp. If during comparison a
              file with younger timestamps is found in the ISO image, then  it  is  suspected  to
              have inconsistent content.
              If  device  numbers and inode numbers of the disk filesystems are persistent and if
              no irregular alterations of timestamps  or  system  clock  happen,  then  potential
              content  changes can be detected without reading that content.  File content change
              is assumed if any of mtime, ctime, device number or inode number have changed.
              Mode "ino_only" replaces the precondition that device numbers  are  stable  by  the
              precondition  that  mount  points  in  the  compared  tree  always lead to the same
              filesystems. Use this if mode "on" always sees all files changed.
              The  speed  advantage  appears  only  if  the  loaded  session  was  produced  with
              -disk_dev_ino "on" too.
              Note  that  -disk_dev_ino  "off"  is totally in effect only if -hardlinks is "off",

       -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 '_'.
              iso_rr_paths with the long components will still be able to access the  file  paths
              with truncated components.
              If -file_name_limit is executed while an ISO tree is present, the file names in the
              ISO tree get checked for existing truncated file names of the current limit and for
              name  collisions  between newly truncated files and existing files.  In both cases,
              the setting will be refused with a SORRY event.
              One may lift  this  ban  by  prepending  the  character  "+"  to  the  argument  of
              -file_name_limit.  Truncated  filenames  may then get truncated again, invalidating
              their MD5 part. Colliding truncated names are made unique,  consuming  at  least  9
              more bytes of the remaining name part.
              If writing of xattr is enabled, then the length will be stored in "isofs.nt" of the
              root directory.  If reading of xattr is enabled and "isofs.nt" is found,  then  the
              found  length  will  get  into  effect if it is smaller than the current setting of
              File name patterns will only work if they match the  truncated  name.   This  might
              change in future.
              Files  with truncated names get deleted and re-added unconditionally during -update
              and -update_r. This might change in future.
              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.  Else just avoid names  longer  than
              253 characters.

       -rom_toc_scan "on"|"force"|"off"[:"emul_off"][:"emul_wide"]
              Read-only  drives do not tell the actual media type but show any media as ROM (e.g.
              as DVD-ROM). The session history of MMC multi-session media might be  truncated  to
              first  and  last  session  or  even  be completely false.  (The emulated history of
              overwriteable media is not affected by this.)
              To have in case of failure a chance of getting the session history  and  especially
              the  address  of  the last session, there is a scan for ISO 9660 filesystem headers
              which might help but also might yield worse  results  than  the  drive's  table  of
              content.  At  its end it can cause read attempts to invalid addresses and thus ugly
              drive behavior.  Setting "on" enables that scan for alleged read-only media.
              Some  operating  systems  are  not  able  to  mount  the  most  recent  session  of
              multi-session  DVD  or  BD. If on such a system xorriso has no own MMC capabilities
              then it may still find that session  from  a  scanned  table  of  content.  Setting
              "force" handles any media like a ROM medium with setting "on".
              On  the  other  hand  the  emulation  of session history on overwriteable media can
              hamper reading  of  partly  damaged  media.  Setting  "off:emul_off"  disables  the
              elsewise trustworthy table-of-content scan for those media.
              The  table-of-content  scan on overwriteable media normally searches only up to the
              end of the session that is pointed to  by  the  superblock  at  block  0.   Setting
              "on:emul_wide"  lets  the  scan  continue up to the end of the medium.  This may be
              useful after copying a medium with -check_media patch_lba0=on  when  not  the  last
              session was loaded.

       -calm_drive "in"|"out"|"all"|"revoke"|"on"|"off"
              Reduce  drive  noise  until  it  is actually used again. Some drives stay alert for
              substantial time after they have been used for reading. This  reduces  the  startup
              time  for  the next drive operation but can be loud and waste energy if no i/o with
              the drive is expected to happen soon.
              Modes  "in",  "out",  "all"  immediately  calm  down  -indev,  -outdev,  or   both,
              respectively.  Mode "revoke" immediately alerts both.  Mode "on" causes -calm_drive
              to be performed automatically after each -dev,  -indev,  and  -outdev.  Mode  "off"
              disables this.

              Allow  for  writing  only  the  usage  of MMC optical drives. Disallow to write the
              result into files of nearly arbitrary type.   Once  set,  this  command  cannot  be

       -early_stdio_test "on"|"appendable_wo"|"off"
              If  enabled  by  "on" then regular files and block devices get tested for effective
              access permissions. This implies to try opening  those  files  for  writing,  which
              otherwise will happen only later and only if actual writing is desired.
              The  test  result  is  used  for  classifying  the  pseudo drives as overwriteable,
              read-only, write-only, or uselessly empty. This may lead to  earlier  detection  of
              severe problems, and may avoid some less severe error events.
              Mode  "appendable_wo"  is  like  "on"  with  the additional property that non-empty
              write-only files are regarded as appendable rather than blank.

       -data_cache_size number_of_tiles blocks_per_tile
              Set the size and granularity of the data cache which is used when  ISO  images  are
              loaded and when file content is read from ISO images. The cache consists of several
              tiles, which each consists of several blocks. A larger cache reduces the  need  for
              tiles  being  read multiple times. Larger tiles might additionally improve the data
              throughput from the drive, but can be wasteful if the data are scattered  over  the
              Larger  cache  sizes  help  best  with  image  loading from MMC drives. They are an
              inferior alternative to -osirrox option "sort_lba_on".
              blocks_per_tile must be a power of 2. E.g. 16, 32, or 64. The  overall  cache  size
              must  not  exceed 1 GiB.  The default values can be restored by parameter "default"
              instead of one or both of the numbers.  Currently the default is  32  tiles  of  32
              blocks = 2 MiB.

       Inserting files into ISO image:

       The following commands expect file addresses of two kinds:
       disk_path is a path to an object in the local filesystem tree.
       iso_rr_path  is  the  Rock Ridge name of a file object in the ISO image.  If no Rock Ridge
       information is recorded in the loaded ISO image, then you will see ISO  9660  names  which
       are  of limited length and character set.  If no Rock Ridge information shall be stored in
       an emerging ISO image, then their names will get mapped to such restricted ISO  9660  (aka
       ECMA-119) names.

       Note that in the ISO image you are as powerful as the superuser. Access permissions of the
       existing files in the image do not apply to your write operations. They are intended to be
       in effect with the read-only mounted image.

       If  the  iso_rr_path  of a newly inserted file leads to an existing file object in the ISO
       image, then the following collision handling happens:
       If both objects are  directories  then  they  get  merged  by  recursively  inserting  the
       subobjects  from  filesystem into ISO image.  If other file types collide then the setting
       of command -overwrite decides.
       Renaming of files has similar collision handling, but directories can  only  be  replaced,
       not  merged. Note that if the target directory exists, then -mv inserts the source objects
       into this directory rather than attempting to replace it.  Command  -move,  on  the  other
       hand, would attempt to replace it.

       The commands in this section alter the ISO image and not the local filesystem.

       -disk_pattern "on"|"ls"|"off"
              Set  the  pattern  expansion  mode for the disk_path parameters of several commands
              which support this feature.
              Setting "off" disables this feature for all commands which are marked in  this  man
              page by "disk_path [***]" or "disk_pattern [***]".
              Setting "on" enables it for all those commands.
              Setting "ls" enables it only for those which are marked by "disk_pattern [***]".
              Default is "ls".

       -add pathspec [...] | disk_path [***]
              Insert the given files or directory trees from filesystem into the ISO image.
              If  -pathspecs  is  set  to  "on"  or "as_mkisofs" then pattern expansion is always
              disabled and character '=' has a special meaning. It separates the ISO  image  path
              from the disk path:
              Character '=' in the iso_rr_path must be escaped by '\' (i.e. as "\=").
              With  -pathspecs  "on", the character '\' must not be escaped. The character '=' in
              the disk_path must not be escaped.
              With  -pathspecs  "as_mkisofs",  all  characters  '\'  must  be  escaped  in  both,
              iso_rr_path  and  disk_path.  The  character  '='  may or may not be escaped in the
              If iso_rr_path does not begin with '/' then -cd is prepended.   If  disk_path  does
              not begin with '/' then -cdx is prepended.
              If no '=' is given then the word is used as both, iso_rr_path and disk path.  If in
              this case the word does not begin with '/' then -cdx is prepended to the  disk_path
              and -cd is prepended to the iso_rr_path.
              If  -pathspecs  is  set  to "off" then -disk_pattern expansion applies, if enabled.
              The resulting words are used as both, iso_rr_path  and  disk  path.  Relative  path
              words  get  prepended  the  setting  of -cdx to disk_path and the setting of -cd to

       -add_plainly mode
              If set to mode "unknown" then any command word that does not begin with "-" and  is
              not recognized as known command will be subject to a virtual -add command.  I.e. it
              will be used as pathspec or as disk_path and  added  to  the  image.   If  enabled,
              -disk_pattern expansion applies to disk_paths.
              Mode "dashed" is similar to "unknown" but also adds unrecognized command words even
              if they begin with "-".
              Mode "any" announces that all further  words  are  to  be  added  as  pathspecs  or
              disk_paths. This does not work in dialog mode.
              Mode "none" is the default. It prevents any words from being understood as files to
              add, if they are not parameters to appropriate commands.

       -path_list disk_path
              Like -add but read the parameter words from file disk_path  or  standard  input  if
              disk_path  is "-".  The list must contain exactly one pathspec or disk_path pattern
              per line.

       -quoted_path_list disk_path
              Like -path_list but with quoted input reading rules. Lines get split into parameter
              words for -add. Whitespace outside quotes is discarded.

       -map disk_path iso_rr_path
              Insert  file  object disk_path into the ISO image as iso_rr_path. If disk_path is a
              directory then its whole sub tree is inserted into the ISO image.

       -map_single disk_path iso_rr_path
              Like -map, but if disk_path is a directory then its sub tree is not inserted.

       -map_l disk_prefix iso_rr_prefix disk_path [***]
              Perform -map with each of the disk_path parameters. iso_rr_path  will  be  composed
              from disk_path by replacing disk_prefix by iso_rr_prefix.

       -update disk_path iso_rr_path
              Compare  file  object disk_path with file object iso_rr_path. If they do not match,
              then perform the necessary image manipulations to make iso_rr_path a matching  copy
              of  disk_path. By default this comparison will imply lengthy content reading before
              a decision is made. Commands -disk_dev_ino or -md5  may  accelerate  comparison  if
              they were already in effect when the loaded session was recorded.
              If  disk_path  is  a  directory  and iso_rr_path does not exist yet, then the whole
              subtree will be inserted. Else only directory attributes will be updated.

       -update_r disk_path iso_rr_path
              Like -update but working recursively. I.e. all file objects  below  both  addresses
              get  compared  whether  they  have counterparts below the other address and whether
              both counterparts  match.  If  there  is  a  mismatch  then  the  necessary  update
              manipulation is done.
              Note  that  the comparison result may depend on command -follow. Its setting should
              always be the same as with the first adding of disk_path as iso_rr_path.
              If iso_rr_path does not exist yet, then it gets added. If disk_path does not exist,
              then iso_rr_path gets deleted.

       -update_l disk_prefix iso_rr_prefix disk_path [***]
              Perform  -update_r  with  each  of  the  disk_path  parameters. iso_rr_path will be
              composed from disk_path by replacing disk_prefix by iso_rr_prefix.

       -update_li iso_rr_prefix disk_prefix iso_rr_path [***]
              Perform -update_r with each  of  the  iso_rr_path  parameters.  disk_path  will  be
              composed from iso_rr_path by replacing iso_rr_prefix by disk_prefix.

       -update_lxi disk_prefix iso_rr_prefix disk_path [***]
              Perform  -update_r  with  each of the disk_path parameters and with iso_rr_paths in
              the ISO filesystem which are derived from the disk_path parameters after exchanging
              disk_prefix  by  iso_rr_prefix.  So,  other  than  -update_l,  this detects missing
              matches of disk_path and deletes the corresponding iso_rr_path.
              Note that relative disk_paths and disk_path patterns are interpreted as  sub  paths
              of  the  current  disk  working  directory -cdx. The corresponding iso_rr_paths are
              derived  by  exchanging  disk_prefix  by  iso_rr_prefix  before  pattern  expansion
              happens. The current -cdi directory has no influence.

       -cut_out disk_path byte_offset byte_count iso_rr_path
              Map  a  byte  interval of a regular disk file into a regular file in the ISO image.
              This may be necessary if the disk file is larger than a single  medium,  or  if  it
              exceeds  the traditional limit of 2 GiB - 1 for old operating systems, or the limit
              of 4 GiB - 1 for newer ones. Only the newest Linux kernels seem  to  read  properly
              files >= 4 GiB - 1.
              A  clumsy remedy for this limit is to backup file pieces and to concatenate them at
              restore time. A well tested chopping size is 2047m.  It is permissible to request a
              higher  byte_count  than  available.  The  resulting  file will be truncated to the
              correct size of a final piece.  To request  a  byte_offset  higher  than  available
              yields no file in the ISO image but a SORRY event.  E.g:
               -cut_out /my/disk/file 0 2047m \
               /file/part_1_of_3_at_0_with_2047m_of_5753194821 \
               -cut_out /my/disk/file 2047m 2047m \
               /file/part_2_of_3_at_2047m_with_2047m_of_5753194821 \
               -cut_out /my/disk/file 4094m 2047m \
              While  command -split_size is set larger than 0, and if all pieces of a file reside
              in the same ISO directory with no other files, and if the names  look  like  above,
              then  their  ISO directory will be recognized and handled like a regular file. This
              affects commands  -compare*,  -update*,  and  overwrite  situations.   See  command
              -split_size for details.

       -cpr disk_path [***] iso_rr_path
              Insert the given files or directory trees from filesystem into the ISO image.
              The rules for generating the ISO addresses are similar as with shell command cp -r.
              Nevertheless, directories of the iso_rr_path are created if necessary. Especially a
              not  yet  existing  iso_rr_path will be handled as directory if multiple disk_paths
              are present.  The leafnames of the multiple disk_paths will be grafted  under  that
              directory as would be done with an existing directory.
              If  a single disk_path is present then a non-existing iso_rr_path will get the same
              type as the disk_path.
              If a disk_path does not begin with '/' then -cdx is prepended.  If the  iso_rr_path
              does not begin with '/' then -cd is prepended.

       -mkdir iso_rr_path [...]
              Create  empty  directories  if  they  do  not  exist  yet.   Existence as directory
              generates a WARNING event, existence as other file causes a FAILURE event.

       -lns target_text iso_rr_path
              Create a symbolic link  with  address  iso_rr_path  which  points  to  target_text.
              iso_rr_path may not exist yet.
              Hint: Command -clone produces the ISO equivalent of a hard link.

       -clone iso_rr_path_original iso_rr_path_copy
              Create  a  copy  of  the  ISO file object iso_rr_path_original with the new address
              iso_rr_path_copy.  If  the  original  is  a  directory  then  copy  all  files  and
              directories  underneath.  If  iso_rr_path_original  is a boot catalog file, then it
              gets not copied but is silently ignored.
              The copied ISO file objects have the same attributes. Copied data  files  refer  to
              the  same  content  source  as their originals.  The copies may then be manipulated
              independendly of their originals.
              This command will refuse execution if the address iso_rr_path_copy  already  exists
              in the ISO tree.

       -cp_clone iso_rr_path_original [***] iso_rr_path_dest
              Create  copies  of one or more ISO file objects as with command -clone.  In case of
              collision merge directories with existing ones, but do not overwrite  existing  ISO
              file objects.
              The  rules for generating the copy addresses are the same as with command -cpr (see
              above) or shell command cp -r. Other than with -cpr, relative  iso_rr_path_original
              will  get  prepended  the  -cd  path  and  not  the  -cdx  path. Consider to -mkdir
              iso_rr_path_dest before -cp_clone so the copy address does not depend on the number
              of iso_rr_path_original parameters.

       Settings for file insertion:

       -file_size_limit value [value [...]] --
              Set  the  maximum permissible size for a single data file. The values get summed up
              for the actual limit. If the only value is "off" then the file size is not  limited
              by xorriso.  Default is a limit of 100 extents, 4g -2k each:
               -file_size_limit 400g -200k --
              When  mounting ISO 9660 filesystems, old operating systems can handle only files up
              to 2g -1 --. Newer ones are good up to 4g -1 --.  You need quite a new Linux kernel
              to  read  correctly  the  final bytes of a file >= 4g if its size is not aligned to
              2048 byte blocks.
              xorriso's own data read capabilities are not  affected  by  operating  system  size
              limits.  Such limits apply to mounting only. Nevertheless, the target filesystem of
              an -extract must be able to take the file size.

       -not_mgt code[:code[...]]
              Control the behavior of the exclusion lists.
              Exclusion processing happens before disk_paths get mapped  to  the  ISO  image  and
              before  disk  files  get  compared with image files.  The absolute disk path of the
              source is matched against the -not_paths list.  The leafname of the  disk  path  is
              matched against the patterns in the -not_leaf list. If a match is detected then the
              disk path will not be regarded as an existing file and not  be  added  to  the  ISO
              Several codes are defined.  The _on/_off settings persist until they are revoked by
              their_off/_on counterparts.
              "erase" empties the lists which were accumulated by -not_paths and -not_leaf.
              "reset" is like "erase" but also re-installs default behavior.
              "off" disables exclusion processing temporarily without invalidating the lists  and
              "on" re-enables exclusion processing.
              "param_off" applies exclusion processing only to paths below disk_path parameter of
              commands. I.e. explicitly given disk_paths are exempted from exclusion processing.
              "param_on" applies exclusion processing to command parameters as well as  to  files
              below such parameters.
              "subtree_off"  with  "param_on"  excludes  parameter  paths  only  if  they match a
              -not_paths item exactly.
              "subtree_on" additionally excludes parameter paths which lead  to  a  file  address
              below any -not_paths item.
              "ignore_off"  treats  excluded  disk  files  as if they were missing. I.e. they get
              reported with -compare and deleted from the image with -update.
              "ignore_on" keeps excluded files out of -compare or -update activities.

       -not_paths disk_path [***]
              Add the given paths to the list of excluded absolute disk paths. If a given path is
              relative,  then  the  current  -cdx is prepended to form an absolute path.  Pattern
              matching, if enabled, happens at definition time and not when exclusion checks  are
              (Do not forget to end the list of disk_paths by "--")

       -not_leaf pattern
              Add  a  single  shell  parser  style  pattern  to  the  list of exclusions for disk
              leafnames. These patterns are evaluated when the exclusion checks are made.

       -not_list disk_path
              Read lines from disk_path and use each of them either as -not_paths  parameter,  if
              they contain a / character, or as -not_leaf pattern.

       -quoted_not_list disk_path
              Like  -not_list  but  with  quoted input reading rules. Each word is handled as one
              parameter for -not_paths or -not_leaf.

       -follow occasion[:occasion[...]]
              Enable or disable resolution of symbolic links and  mountpoints  under  disk_paths.
              This  applies  to actions -add, -du*x, -ls*x, -findx, -concat, and to -disk_pattern
              There are three kinds of follow decisison to be made:
              link is the hop from a symbolic link to its target file object for the  purpose  of
              reading.  I.e. not for command -concat.  If enabled then symbolic links are handled
              as their target file objects, else symbolic links are handled as themselves.
              mount is the hop from one filesystem to another subordinate filesystem.  If enabled
              then  mountpoint  directories  are handled as any other directory, else mountpoints
              are handled as  empty  directories  if  they  are  encountered  in  directory  tree
              concat is the hop from a symbolic link to its target file object for the purpose of
              writing. I.e. for command -concat. This is a security risk !
              Less general than above occasions:
              pattern is mount and link hopping, but only during -disk_pattern expansion.
              param is link hopping for parameter words (after eventual pattern  expansion).   If
              enabled  then  -ls*x  will  show the link targets rather than the links themselves.
              -du*x, -findx, and -add will process the link targets but not follow  links  in  an
              eventual directory tree below the targets (unless "link" is enabled).
              Occasions can be combined in a colon separated list. All occasions mentioned in the
              list will then lead to a positive follow decision.
              off prevents any positive follow decision. Use it if no other occasion applies.
              default is equivalent to "pattern:mount:limit=100".
              on always decides positive. Equivalent to "link:mount:concat".

              Not an occasion but an optional setting is:
              limit=<number> which sets the maximum number of link hops.  A link hop consists  of
              a  sequence  of  symbolic  links and a final target of different type. Nevertheless
              those hops can loop. Example:
                $ ln -s .. uploop
              Link hopping has a built-in  loop  detection  which  stops  hopping  at  the  first
              repetition of a link target. Then the repeated link is handled as itself and not as
              its target.  Regrettably one can construct link networks  which  cause  exponential
              workload  before their loops get detected.  The number given with "limit=" can curb
              this workload at the risk of truncating an intentional sequence of link hops.

       -pathspecs "on"|"off"|"as_mkisofs"
              Control parameter interpretation with xorriso actions -add and -path_list.
              Mode "as_mkisofs" enables pathspecs of the form
              like with program mkisofs -graft-points.
              All characters '\' must  be  escaped  in  both,  iso_rr_path  and  disk_path.   The
              character  '='  must be escaped in the iso_rr_path and may or may not be escaped in
              the disk_path.  This mode temporarily disables -disk_pattern expansion for  command
              Mode "on" does nearly the same. But '=' must only be escaped in the iso_rr_path and
              '\' must not be escaped at all. This has the disadvantage that one  cannot  express
              an iso_rr_path which ends by '\'.
              Mode   "off"   disables   pathspecs   of  the  form  target=source  and  re-enables
              -disk_pattern expansion.

       -overwrite "on"|"nondir"|"off"
              Allow or disallow overwriting of existing files in the ISO image by files with  the
              same name.
              With  setting  "off",  name  collisions  with at least one non-directory file cause
              FAILURE events. Collisions of two directories lead to merging of their file lists.
              With setting "nondir",  only  directories  are  protected  by  such  events,  other
              existing  file  types get treated with -rm before the new file gets added.  Setting
              "on" enables  automatic  -rm_r.  I.e.  a  non-directory  can  replace  an  existing
              directory and all its subordinates.
              If  restoring  of  files  is enabled, then the overwrite rule applies to the target
              file objects on disk as well, but "on" is downgraded to "nondir".

       -split_size number["k"|"m"]
              Set the threshold for automatic splitting of regular files. Such splitting  maps  a
              large  disk  file  onto  a  ISO  directory  with several part files in it.  This is
              necessary if the size of the disk file exceeds -file_size_limit.   Older  operating
              systems  can  handle files in mounted ISO 9660 filesystems only if they are smaller
              than 2 GiB or in other cases 4 GiB.
              Default is 0 which will exclude files larger than  -file_size_limit  by  a  FAILURE
              event.   A  well  tested -split_size is 2047m. Sizes above -file_size_limit are not
              While command -split_size is set larger than 0 such a  directory  with  split  file
              pieces  will  be recognized and handled like a regular file by commands -compare* ,
              -update*,  and   in   overwrite   situations.   There   are   -osirrox   parameters
              "concat_split_on"  and "concat_split_off" which control the handling when files get
              restored to disk.
              In order to be recognizable, the names of the  part  files  have  to  describe  the
              splitting by 5 numbers:
              which are embedded in the following text form:
              Scaling  characters  like  "m"  or  "k"  are  taken  into  respect.  All digits are
              interpreted as decimal, even if leading zeros are present.
              E.g: /file/part_1_of_3_at_0_with_2047m_of_5753194821
              No other files are allowed in the directory. All parts have to be present and their
              numbers  have  to be plausible. E.g. byte_count must be valid as -cut_out parameter
              and their contents may not overlap.

       File manipulations:

       The following commands manipulate files in the ISO image,  regardless  whether  they  stem
       from the loaded image or were newly inserted.

       -iso_rr_pattern "on"|"ls"|"off"
              Set  the  pattern expansion mode for the iso_rr_path parameters of several commands
              which support this feature.
              Setting "off" disables pattern expansion for all commands which are marked in  this
              man page by "iso_rr_path [***]" or "iso_rr_pattern [***]".
              Setting "on" enables it for all those commands.
              Setting "ls" enables it only for those which are marked by "iso_rr_pattern [***]".
              Default is "on".

       -rm iso_rr_path [***]
              Delete the given files from the ISO image.
              Note:  This  does  not free any space on the -indev medium, even if the deletion is
              committed to that same medium.
              The image size will shrink if the  image  is  written  to  a  different  medium  in
              modification mode.

       -rm_r iso_rr_path [***]
              Delete  the  given  files or directory trees from the ISO image.  See also the note
              with command -rm.

       -rmdir iso_rr_path [***]
              Delete empty directories.

       -move iso_rr_path iso_rr_path
              Rename the file given by the first (origin) iso_rr_path to the second (destination)
              iso_rr_path.   Deviate from rules of shell command mv by not moving the origin file
              underneath an existing destination directory. The origin file will  rather  replace
              such a directory, if this is allowed by command -overwrite.

       -mv iso_rr_path [***] iso_rr_path
              Rename  the  given  file objects in the ISO tree to the last parameter in the list.
              Use the same rules as with shell command mv.
              If pattern expansion is  enabled  and  if  the  last  parameter  contains  wildcard
              characters  then  it  must  match  exactly  one  existing file address, or else the
              command fails with a FAILURE event.

       -chown uid iso_rr_path [***]
              Set ownership of file objects in the ISO image. uid may either be a decimal  number
              or the name of a user known to the operating system.

       -chown_r uid iso_rr_path [***]
              Like -chown but affecting all files below eventual directories.

       -chgrp gid iso_rr_path [***]
              Set  group attribute of file objects in the ISO image. gid  may either be a decimal
              number or the name of a group known to the operating system.

       -chgrp_r gid iso_rr_path [***]
              Like -chgrp but affecting all files below eventual directories.

       -chmod mode iso_rr_path [***]
              Equivalent to shell command chmod in the ISO image.  mode is either an octal number
              beginning   with  "0"  or  a  comma  separated  list  of  statements  of  the  form
              [ugoa]*[+-=][rwxst]* .
              Like: go-rwx,u+rwx .
              Personalities: u=user, g=group, o=others, a=all
              Operators: + adds given permissions, - revokes given permissions, = revokes all old
              permissions and then adds the given ones.
              Permissions: r=read, w=write, x=execute|inspect, s=setuid|setgid, t=sticky bit
              For octal numbers see man 2 stat.

       -chmod_r mode iso_rr_path [***]
              Like -chmod but affecting all files below eventual directories.

       -setfacl acl_text iso_rr_path [***]
              Attach  the  given  ACL  to the given iso_rr_paths. If the files already have ACLs,
              then those get deleted before the new ones get into effect.  If acl_text is  empty,
              or  contains  the  text  "clear" or the text "--remove-all", then the existing ACLs
              will be removed and no new ones will be attached. Any  other  content  of  acl_text
              will  be  interpreted  as  a  list of ACL entries. It may be in the long multi-line
              format as put out by -getfacl but may also be abbreviated as follows:
              ACL entries are separated by comma or newline. If an entry is empty text or  begins
              with  "#"  then  it  will be ignored. A valid entry has to begin by a letter out of
              {ugom} for "user", "group", "other", "mask". It has to contain two  colons  ":".  A
              non-empty  text between those ":" gives a user id or group id. After the second ":"
              there may be letters out of {rwx- #}.  The first three give read, write, or execute
              permission.  Letters "-", " " and TAB are ignored. "#" causes the rest of the entry
              to be ignored. Letter "X" or any other letters are not supported. Examples:
              A valid entry may be prefixed by "d", some  following  characters  and  ":".   This
              indicates that the entry goes to the "default" ACL rather than to the "access" ACL.

       -setfacl_r acl_text iso_rr_path [***]
              Like -setfacl but affecting all files below eventual directories.

       -setfacl_list disk_path
              Read the output of -getfacl_r or shell command getfacl  -R  and  apply  it  to  the
              iso_rr_paths  as  given  in  lines  beginning  with  "#  file:".  This  will change
              ownership, group and ACL of the given files.  If disk_path is "-"  then  lines  are
              read from standard input. Line "@" ends the list, "@@@" aborts without changing the
              pending iso_rr_path.
              Since -getfacl and getfacl -R strip leading "/" from file paths, the setting of -cd
              does always matter.

       -setfattr [-]name value iso_rr_path [***]
              Attach  the  given  xattr pair of name and value to the given iso_rr_paths.  If the
              given name is prefixed by "-", then the pair with that name gets removed  from  the
              xattr  list.  If  name is "--remove-all" then all user namespace xattr of the given
              iso_rr_paths get deleted. In case of deletion, value must be an empty text.
              Which names are permissible depends on the setting  of  command  -xattr.   "on"  or
              "user" restricts them to namespace "user". I.e. a name has to look like "user.x" or
              -xattr setting "any" enables names from all namespaces except "isofs".
              Values and names undergo the normal input processing of xorriso.  See also  command
              -backslash_codes.  Other  than with command -setfattr_list, the byte value 0 cannot
              be expressed via -setfattr.

       -setfattr_r [-]name value iso_rr_path [***]
              Like -setfattr but affecting all files below eventual directories.

       -setfattr_list disk_path
              Read the output format of -getfattr_r or shell command getfattr -Rd and apply it to
              the  iso_rr_paths  as  given  in  lines  beginning  with "# file:".  All previously
              existing xattr of the acceptable namespaces will be deleted before  the  new  xattr
              get attached. The set of acceptable names depends on the setting of command -xattr.
              If disk_path is "-" then lines are read from standard input.
              Since  -getfattr and getfattr -Rd strip leading "/" from file paths, the setting of
              -cd does always matter.
              Empty input lines and lines which begin by "#" will be ignored (except "#  file:").
              Line  "@"  ends  the  list,  "@@@" aborts without changing the pending iso_rr_path.
              Other input lines must have the form
              The separator "=" is not allowed in names.  Value may contain any kind of bytes. It
              must  be  in  quotes.  Trailing  whitespace  after  the  end quote will be ignored.
              Non-printables bytes and quotes must be represented as \XYZ by  their  octal  8-bit
              code XYZ.  Use code \000 for 0-bytes.

       -alter_date type timestring iso_rr_path [***]
              Alter the date entries of files in the ISO image. type may be one of the following:
              "a" sets access time, updates ctime.
              "m" sets modification time, updates ctime.
              "b" sets access time and modification time, updates ctime.
              "a-c", "m-c", and "b-c" set the times without updating ctime.
              "c" sets the ctime.
              timestring may be in the following formats (see also section EXAMPLES):
              As expected by program date:
              As produced by program date:
               [Day] MMM DD hh:mm:ss [TZON] YYYY
              Relative times counted from current clock time:
              where  "s" means seconds, "h" hours, "d" days, "w" weeks, "m"=30d, "y"=365.25d plus
              1d added to multiplication result.
              Absolute seconds counted from Jan 1 1970:
              xorriso's own timestamps:
              scdbackup timestamps:
              where "A0" is year 2000, "B0" is 2010, etc.
              ECMA-119 volume timestamps:
              These are normally given as GMT. The suffix "LOC" causes local timezone conversion.
              E.g.  2013010720574700, 2013010720574700LOC.  The last two digits cc (centiseconds)
              will be ignored, but must be present in order to make the format recognizable.
                -alter_date m-c 2013.11.27.103951 /file1 /file2 --
              This command does not persistently apply to the  boot  catalog,  which  gets  fresh
              timestamps at -commit time. Command -volume_date "uuid" can set this time value.

       -alter_date_r type timestring iso_rr_path [***]
              Like -alter_date but affecting all files below eventual directories.

       -hide hide_state iso_rr_path [***]
              Prevent  the names of the given files from showing up in the directory trees of ISO
              9660 and/or Joliet and/or HFS+ when the image gets written.  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
              Warning:  Data  which  are  hidden from the ISO 9660 tree will not be copied by the
              write method of modifying.
              Possible values of hide_state are: "iso_rr" for hiding from ISO 9660 tree, "joliet"
              for  Joliet tree, "hfsplus" for HFS+, "on" for them all.  "off" means visibility in
              all directory trees.
              These values may be combined.  E.g.: joliet:hfsplus
              This command does not apply to the boot catalog.   Rather  use:  -boot_image  "any"

       Tree traversal command -find:

       -find iso_rr_path [test [op] [test ...]] [-exec action [params]] --
              A  restricted  substitute  for shell command find in the ISO image.  It performs an
              action on matching file objects at or below iso_rr_path.
              If not used as last command in the line  then  the  parameter  list  needs  to  get
              terminated by "--".
              Tests are optional. If they are omitted then action is applied to all file objects.
              If tests are given then they form together an expression.  The  action  is  applied
              only if the expression matches the file object. Default expression operator between
              tests is -and, i.e. the expression matches only if all its tests match.
              Available tests are:
              -name pattern : Matches if pattern matches the file leaf name. If the pattern  does
              not  contain  any  of  the characters "*?[", then it will be truncated according to
              -file_name_limit and thus match the truncated name in the ISO filesystem.
              -wholename pattern : Matches if pattern matches  the  file  path  as  it  would  be
              printed  by  action  "echo".  Character '/' can be matched by wildcards. If pattern
              pieces between '/' do not contain  any  of  the  characters  "*?[",  they  will  be
              truncated according to -file_name_limit.
              -disk_name  pattern  :  Like  -name but testing the leaf name of the file source on
              disk.  Can match only data files which do not stem from the loaded  image,  or  for
              directories  above  such data files. With directories the result can change between
              -find runs if their content stems from multiple sources.
              -disk_path disk_path : Matches if the given disk_path is equal to the path  of  the
              file source on disk. The same restrictions apply as with -disk_name.
              -type  type_letter  :  Matches  files  of  the  given type: "block", "char", "dir",
              "pipe", "file", "link", "socket", "eltorito", and "Xotic" which matches what is not
              matched by the other types.
              Only the first letter is interpreted.  E.g.: -find / -type d
              -maxdepth  number  :  Matches only files which are at most at the given depth level
              relative to the iso_rr_path where -find starts. That path itself is at depth 0, its
              directory children are at 1, their directory children at 2, and so on.
              -mindepth number : Matches only files which are at least at the given depth level.
              -damaged  : Matches files which use data blocks marked as damaged by a previous run
              of -check_media. The damage info vanishes when a new ISO image gets loaded.
              Note that a MD5 session mismatch marks all files of the  session  as  damaged.   If
              finer distinction is desired, perform -md5 off before -check_media.
              -pending_data  :  Matches files which get their content from outside the loaded ISO
              -lba_range start_lba block_count : Matches files which use data blocks  within  the
              range of start_lba and start_lba+block_count-1.
              -has_acl : Matches files which have a non-trivial ACL.
              -has_xattr : Matches files which have xattr name-value pairs from user namespace.
              -has_aaip : Matches files which have ACL or any xattr.
              -has_any_xattr : Matches files which have any xattr other than ACL.
              -has_md5 : Matches data files which have MD5 checksums.
              -has_hfs_crtp  creator  type  : Matches files which have the given HFS+ creator and
              type attached.  These are codes of 4 characters which get  stored  if  -hfsplus  is
              enabled. Use a single dash '-' as wildcard that matches any such code.  E.g:.
               -has_hfs_crtp YYDN TEXT
               -has_hfs_crtp - -
              -has_hfs_bless  blessing : Matches files which bear the given HFS+ blessing. It may
              be  one  of  :  "ppc_bootdir",   "intel_bootfile",   "show_folder",   "os9_folder",
              "osx_folder", "any". See also action set_hfs_bless.
              -has_filter : Matches files which are filtered by -set_filter.
              -hidden  hide_state  : Matches files which are hidden in "iso_rr" tree, in "joliet"
              tree, in "hfsplus" tree, in all trees ("on"), or not hidden in any tree ("off").
              Those which are hidden in some tree match -not -hidden "off".
              -bad_outname namespace : Matches files with names which change when converted forth
              and  back  between  the  local character set and one of the namespaces "rockridge",
              "joliet", "ecma119", "hfsplus".
              All applicable -compliance rules are taken into respect.   Rule  "omit_version"  is
              always  enabled, because else namespaces "joliet" and "ecma119" would cause changes
              with every non-directory name.  Consider to also enable rules  "no_force_dots"  and
              The  namespaces use different character sets and apply further restrictions to name
              length, permissible characters, and mandatory name  components.   "rockridge"  uses
              the  character  set  defined by -out_charset, "joliet" uses UCS-2BE, "ecma119" uses
              ASCII, "hfsplus" uses UTF-16BE.
              -name_limit_blocker length  :  Matches  file  names  which  would  prevent  command
              -file_name_limit  with  the given length. The command itself reports only the first
              problem file.
              -prune : If this test is reached and the tested file is a directory then -find will
              not dive into that directory. This test itself does always match.
              -use_pattern "on"|"off" : This pseudo test controls the interpretation of wildcards
              with tests -name, -wholename, and -disk_name. Default is "on". If interpretation is
              disabled by "off", then the parameters of -name, -wholename, and -disk_name have to
              match literally rather than as search pattern.  This test itself does always match.
              -or_use_pattern "on"|"off" : Like -use_pattern,  but  automatically  appending  the
              test  by  -or  rather  than by -and. Further the test itself does never match. So a
              subsequent test -or will cause its other operand to be performed.
              -decision "yes"|"no" : If this test is reached then the evaluation ends immediately
              and action is performed if the decision is "yes" or "true". See operator -if.
              -true and -false : Always match or match not, respectively. Evaluation goes on.
              -sort_lba  :  Always  match.  This causes -find to perform its action in a sequence
              sorted by the ISO image block addresses of the files.  It  may  improve  throughput
              with  actions  which  read  data  from  optical  drives. Action will always get the
              absolute path as parameter.
              Available operators are:
              -not : Matches if the next test or sub expression does not match.  Several tests do
              this specifically:
              -undamaged,   -lba_range   with  negative  start_lba,  -has_no_acl,  -has_no_xattr,
              -has_no_aaip, -has_no_filter .
              -and : Matches if both neighboring tests or expressions match.
              -or : Matches if at least one of both neighboring tests or expressions matches.
              -sub ... -subend or ( ... ) : Enclose a sub expression which gets  evaluated  first
              before it is processed by neighboring operators.  Normal precedence is: -not, -or ,
              -if ... -then ... -elseif ... -then ...  -else ... -endif : Enclose one or more sub
              expressions.  If the -if expression matches, then the -then expression is evaluated
              as the result of  the  whole  expression  up  to  -endif.  Else  the  next  -elseif
              expression is evaluated and if it matches, its -then expression. Finally in case of
              no match, the -else expression is evaluated.  There may be more than  one  -elseif.
              Neither  -else  nor  -elseif  are mandatory.  If -else is missing and would be hit,
              then the result is a non-match.
              -if-expressions are the main use case for above test -decision.

              Default action is echo, i.e. to print the address of the found file. Other  actions
              are  certain  xorriso  commands  which  get  performed  on  the found files.  These
              commands may have specific parameters. See also their particular descriptions.
              chown and chown_r change the ownership and get the  user  id  as  parameter.  E.g.:
              -exec chown thomas --
              chgrp  and  chgrp_r  change  the group attribute and get the group id as parameter.
              E.g.: -exec chgrp_r staff --
              chmod and chmod_r change access permissions and get a  mode  string  as  parameter.
              E.g.: -exec chmod a-w,a+r --
              alter_date  and alter_date_r change the timestamps. They get a type character and a
              timestring as parameters.
              E.g.: -exec alter_date "m" "Dec 30 19:34:12 2007" --
              set_to_mtime sets the ctime and atime to the value found in mtime.
              lsdl prints file information like shell command ls -dl.
              compare performs command -compare with the found file address  as  iso_rr_path  and
              the  corresponding  file  address below its parameter disk_path_start. For this the
              iso_rr_path of the -find command gets replaced by the disk_path_start.
              E.g.: -find /thomas -exec compare /home/thomas --
              update performs command -update with the found file  address  as  iso_rr_path.  The
              corresponding file address is determined like with above action "compare".
              update_merge  is like update but does not delete the found file if it is missing on
              disk.  It may be run several times and records with all visited files whether their
              counterpart  on  disk  has  already  been  seen  by  one  of the update_merge runs.
              Finally, a -find run with action "rm_merge"  may  remove  all  files  that  saw  no
              counterpart on disk.
              Up to the next "rm_merge" or "clear_merge" all newly inserted files will get marked
              as having a disk counterpart.
              rm removes the found iso_rr_path from the image if it is not a directory with files
              in it. I.e. this "rm" includes "rmdir".
              rm_r removes the found iso_rr_path from the image, including whole directory trees.
              rm_merge  removes  the  found iso_rr_path if it was visited by one or more previous
              actions "update_merge" and saw no counterpart on disk in any of them.  The  marking
              from the update actions is removed in any case.
              clear_merge removes an eventual marking from action "update_merge".
              report_damage  classifies  files  whether  they  hit a data block that is marked as
              damaged. The result is printed together with the address of the first damaged byte,
              the maximum span of damages, file size, and the path of the file.
              report_lba  prints  files  which are associated to image data blocks.  It tells the
              logical block address, the block number, the byte size, and the path of each  file.
              There  may  be  reported  more than one line per file if the file has more than one
              section.  In this case each line has a different extent number in column "xt".
              report_sections like report_lba but  telling  the  byte  sizes  of  the  particular
              sections rather than the overall byte size of the file.
              getfacl prints access permissions in ACL text form to the result channel.
              setfacl  attaches  ACLs  after removing existing ones. The new ACL is given in text
              form as defined with command -setfacl.
              E.g.: -exec setfacl u:lisa:rw,u::rw,g::r,o::-,m::rw --
              getfattr prints xattr name-value  pairs  to  the  result  channel.  The  choice  of
              namespaces depends on the setting of command -xattr: "on" or "user" restricts it to
              the namespace "user", "any" only omits namespace "isofs".
              get_any_xattr prints xattr name-value pairs from any namespace except  ACL  to  the
              result channel. This is mostly for debugging of namespace "isofs".
              list_extattr  mode  prints  a script to the result channel, which would use FreeBSD
              command setextattr to set the file's xattr  name-value  pairs  of  user  namespace.
              Parameter  mode  controls the form of the output of names and values.  Default mode
              "e" prints harmless characters in shell quotation marks, but represents texts  with
              octal  001 to 037 and 0177 to 0377 by an embedded echo -e command.  Mode "q" prints
              any characters in shell quotation marks. This might not be terminal-safe but should
              work in script files.  Mode "r" uses no quotation marks. Not safe.  Mode "b" prints
              backslash encoding. Not suitable for shell parsing.
              E.g. -exec list_extattr e --
              Command -backslash_codes does not affect the output.
              get_md5 prints the MD5 sum, if recorded, together with file path.
              check_md5 compares the MD5 sum, if recorded, with the file content and  reports  if
              E.g.: -find / -not -pending_data -exec check_md5 FAILURE --
              make_md5  equips  a data file with an MD5 sum of its content. Useful to upgrade the
              files in the loaded image to full MD5 coverage by the next commit with -md5 "on".
              E.g.: -find / -type f -not -has_md5 -exec make_md5 --
              setfattr sets or deletes xattr name value pairs.
              E.g.: -find / -has_xattr -exec setfattr --remove-all '' --
              set_hfs_crtp adds, changes, or removes HFS+ creator and type attributes.
              E.g.: -exec set_hfs_crtp YYDN TEXT
              E.g.: -find /my/dir -prune -exec set_hfs_crtp --delete -
              get_hfs_crtp prints  the  HFS+  creator  and  type  attributes  together  with  the
              iso_rr_path, if the file has such attributes at all.
              E.g.: -exec get_hfs_crtp
              set_hfs_bless  applies  or  removes  HFS+  blessings.  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.  The
              -find run will end as soon as the first blessing is issued. The previous bearer  of
              the blessing will lose it then.  No file object can bear more than one blessing.
              E.g.: -find /my/blessed/directory -exec set_hfs_bless p
              Further  there  is blessing "none" or "n" which revokes any blessing from the found
              files. This -find run will not stop when the first match is reached.
              E.g.: -find / -has_hfs_bless any -exec set_hfs_bless none
              get_hfs_bless prints the HFS+ blessing role and the iso_rr_path,  if  the  file  is
              blessed at all.
              E.g.: -exec get_hfs_bless
              set_filter applies or removes filters.
              E.g.: -exec set_filter --zisofs --
              mkisofs_r applies the rules of mkisofs -r to the file object:
              user  id  and  group  id become 0, all r-permissions get granted, all w denied.  If
              there is any x-permission, then all  three  x  get  granted.   s-  and  t-bits  get
              sort_weight attributes a LBA weight number to regular files.
              The  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  boot  catalog  has a hardcoded weight of 1 billion.  Normally it should occupy
              the block with the lowest possible address.
              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.
              Data files which are added by other commands get an  initial  weight  of  0.   Boot
              image files have a default weight of 2.
              E.g.: -exec sort_weight 3 --
              show_stream shows the content stream chain of a data file.
              show_stream_id  is  like show_stream, but also prints between stream type and first
              ":" in square brackets libisofs id numbers: [fs_id,dev_id,ino_id].
              hide brings the file  into  one  of  the  hide  states  "on",  "iso_rr",  "joliet",
              "hfsplus", "off". They may be combined. E.g.: joliet:hfsplus
                -find / -disk_name *_secret -exec hide on
              print_outname  prints  in  the first line the filename as registered by the program
              model, and in the second line the filename after conversion forth and back  between
              local  character set and one of the namespaces "rockridge", "joliet", "ecma119", or
              "hfsplus". The third output line is "--" .
              The name conversion does not take into respect the possibility of  name  collisions
              in the target namespace. Such collisions are most likely in "joliet" and "ecma119",
              where they get resolved by automatic file name changes.
                -find / -bad_outname joliet -exec print_outname joliet
              estimate_size prints a lower and an upper estimation of the number of blocks  which
              the  found  files  together  will  occupy in the emerging ISO image.  This does not
              account for the superblock, for the directories in the -find  path,  or  for  image
              find  performs  another  run of -find on the matching file address.  It accepts the
              same params as -find, except iso_rr_path.
                -find / -name '???' -type d -exec find -name '[abc]*' -exec chmod a-w,a+r --

       Filters for data file content:

       Filters may be installed between data files in the ISO  image  and  their  content  source
       outside  the image. They may also be used vice versa between data content in the image and
       target files on disk.
       Built-in filters are "--zisofs" and "--zisofs-decode". The former is  to  be  applied  via
       -set_filter,  the latter is automatically applied if zisofs compressed content is detected
       with a file when loading the ISO image.
       Another built-in filter pair is "--gzip" and "--gunzip" with suffix  ".gz".   They  behave
       about  like  external gzip and gunzip but avoid forking a process for each single file. So
       they are much faster if there are many small files.

       -external_filter name option[:option] program_path [arguments] --
              Register a content filter by associating  a  name  with  a  program  path,  program
              arguments,  and  some  behavioral  options.  Once  registered  it can be applied to
              multiple data files in the ISO image, regardless whether their content  resides  in
              the  loaded  ISO  image  or in the local filesystem.  External filter processes may
              produce synthetic file content by reading  the  original  content  from  stdin  and
              writing  to  stdout  whatever  they want.  They must deliver the same output on the
              same input in repeated runs.
              Options are:
               "default" means that no other option is intended.
               "suffix=..." sets a file name suffix. If it is not empty then it will be  appended
              to the file name or removed from it.
               "remove_suffix" will remove a file name suffix rather than appending it.
               "if_nonempty" will leave 0-sized files unfiltered.
               "if_reduction"  will  try  filtering  and  revoke  it if the content size does not
               "if_block_reduction" will revoke if the number of 2 kB blocks does not shrink.
               "used=..." is ignored. Command -status shows it with the  number  of  files  which
              currently have the filter applied.
               -external_filter bzip2 suffix=.bz2:if_block_reduction \
                                /usr/bin/bzip2 --
               -external_filter bunzip2 suffix=.bz2:remove_suffix \
                                /usr/bin/bunzip2 --

       -unregister_filter name
              Remove an -external_filter registration. This is only possible if the filter is not
              applied to any file in the ISO image.

              Irrevocably ban commands -concat "pipe", -external_filter, and  -unregister_filter,
              but  not -set_filter. Use this to prevent external filtering in general or when all
              intended filters are registered  and  -concat  mode  "pipe"  shall  be  disallowed.
              External filters may also be banned totally at compile time of xorriso.  By default
              they are banned if xorriso runs under setuid permission.

       -set_filter name iso_rr_path [***]
              Apply an -external_filter or a built-in filter to the given data files in  the  ISO
              image.   If  the  filter  suffix is not empty , then it will be applied to the file
              name.  Renaming only happens if the filter really gets attached and is not  revoked
              by  its  options.   By  default  files  which  already bear the suffix will not get
              filtered. The others will get the suffix appended to their names.   If  the  filter
              has  option  "remove_suffix", then the filter will only be applied if the suffix is
              present and can be removed.  Name oversize or collision  caused  by  suffix  change
              will prevent filtering.
              With  most  filter types this command will immediately run the filter once for each
              file in order to determine  the  output  size.   Content  reading  operations  like
              -extract  ,  -compare  and  image  generation  will perform further filter runs and
              deliver filtered content.
              At image generation time the filter output must still be the  same  as  the  output
              from  the first run. Filtering for image generation does not happen with files from
              the loaded ISO image if the write method of growing is in effect  (i.e  -indev  and
              -outdev are identical).
              The reserved filter name "--remove-all-filters" revokes filtering. This will revoke
              suffix renamings as  well.   Use  "--remove-all-filters+"  to  prevent  any  suffix
              Attaching  or  detaching  filters will not alter the state of -changes_pending.  If
              the filter manipulations shall be the only changes in a write run, then  explicitly
              execute -changes_pending "yes".

       -set_filter_r name iso_rr_path [***]
              Like -set_filter but affecting all data files below eventual directories.

       Writing the result, drive control:

       (see also paragraph about settings below)

              Discard the manipulated ISO image and reload it from -indev.  (Use -rollback_end if
              immediate program end is desired.)

       -changes_pending "no"|"yes"|"mkisofs_printed"|"show_status"
              Write runs are performed only if a change of the image  has  been  made  since  the
              image  was  loaded  or created blank. Vice versa the program will start a write run
              for pending changes when it ends normally (i.e. not by abort  and  not  by  command
              The  command  -changes_pending can be used to override the automatically determined
              state. This is mainly useful for setting state "yes" despite no real  changes  were
              made.  The  sequence  -changes_pending  "no"  -end  is  equivalent  to  the command
              -rollback_end. State "mkisofs_printed" is caused by emulation command  -as  mkisofs
              if option -print-size is present.
              The  pseudo-state  "show_status"  can  be used to print the current state to result
              Image loading or manipulations which happen after this command  will  again  update
              automatically the change status of the image.

              Perform  the  write  operation. Afterwards, if -outdev is readable, make it the new
              -dev and load the image from there.  Switch to growing mode.  (A subsequent -outdev
              will   activate   modification  mode  or  blind  growing.)   -commit  is  performed
              automatically at end of program if there are uncommitted manipulations pending.
              So, to perform a final write operation with no new  -dev  and  no  new  loading  of
              image,  rather  execute  command -end.  If you want to go on without image loading,
              execute -commit_eject "none".  To eject after  write  without  image  loading,  use
              -commit_eject "all".
              To suppress a final write, execute -rollback_end.

              Writing can last quite a while. It is not unnormal with several types of media that
              there is no progress visible for the first few minutes or that the drive  gnaws  on
              the medium for a few minutes after all data have been transmitted.  xorriso and the
              drives are in a client-server relationship.  The drives  have  much  freedom  about
              what  to  do  with  the media.  Some combinations of drives and media simply do not
              work, despite the promises by their vendors.  If writing fails then try other media
              or  another  drive.  The  reason for such failure is hardly ever in the code of the
              various burn programs but you may well try some of those  listed  below  under  SEE

       -eject "in"|"out"|"all"
              Eject the medium in -indev, -outdev, or both drives, respectively.  Note: It is not
              possible yet to effectively eject disk files.

       -commit_eject "in"|"out"|"all"|"none"
              Combined -commit and -eject. When writing has finished do not make -outdev the  new
              -dev,  and  load  no  ISO  image.  Rather  eject -indev and/or -outdev. Give up any
              non-ejected drive.

       -blank mode
              Make media ready for writing from scratch (if not -dummy is activated).
              This affects only the -outdev not the -indev.  If both drives are the same  and  if
              the  ISO  image  was  altered  then this command leads to a FAILURE event.  Defined
              modes are:
                as_needed, fast, all, deformat, deformat_quickest
              "as_needed" cares for used CD-RW,  DVD-RW  and  for  used  overwriteable  media  by
              applying  -blank  "fast". It applies -format "full" to  yet unformatted DVD-RAM and
              BD-RE. Other media in blank state are gracefully ignored.  Media  which  cannot  be
              made ready for writing from scratch cause a FAILURE event.
              "fast"  makes  CD-RW and unformatted DVD-RW re-usable, or invalidates overwriteable
              ISO images. "all" might work more thoroughly and need more time.
              "deformat" converts overwriteable DVD-RW into unformatted ones.
              "deformat_quickest" is a faster way to deformat or blank DVD-RW but produces  media
              which  are  only suitable for a single session.  Some drives announce this state by
              not offering feature 21h, but some drives offer  it  anyway.   If  feature  21h  is
              missing,  then  xorriso will refuse to write on DVD-RW if not command -close is set
              to "on".
              The progress reports issued by some drives while blanking are quite unrealistic. Do
              not  conclude  success  or  failure  from  the  reported  percentages. Blanking was
              successful if no SORRY event or worse occurred.
              Mode may be prepended by "force:" in order to override the evaluation of the medium
              state  by  libburn.  E.g. "force:fast".  Blanking will nevertheless only succeed if
              the drive is willing to do it.

       -format mode
              Convert unformatted DVD-RW into overwriteable ones, "de-ice" DVD+RW,  format  newly
              purchased BD-RE or BD-R, re-format DVD-RAM or BD-RE.
              Defined modes are:
                as_needed, full, fast, by_index_<num>, fast_by_index_<num>,
                by_size_<num>, fast_by_size_<num>, without_spare
              "as_needed"  formats  yet  unformatted DVD-RW, DVD-RAM, BD-RE, or blank unformatted
              BD-R. Other media are left untouched.
              "full" (re-)formats DVD-RW, DVD+RW, DVD-RAM, BD-RE, or blank unformatted BD-R.
              "fast" does the same as "full" but tries to be quicker.
              "by_index_" selects  a  format  out  of  the  descriptor  list  issued  by  command
              -list_formats.  The index number from that list is to be appended to the mode word.
              E.g: "by_index_3".
              "fast_by_index_" does the same as "by_index_" but tries to be quicker.
              "by_size_" selects a format out of the descriptor list which provides at least  the
              given  size.  That  size is to be appended to the mode word.  E.g: "by_size_4100m".
              This applies to media with Defect Management.  On BD-RE it will not  choose  format
              0x31, which offers no Defect Management.
              "fast_by_size_" does the same as "by_size_" but tries to be quicker.
              "without_spare"  selects  the  largest  format  out  of  the  descriptor list which
              provides no Spare Area for Defect Management. On BD-RE this will be format 0x31.
              The formatting action has no effect on media if -dummy is activated.
              Formatting is normally needed only once during the lifetime of a medium,  if  ever.
              But it is a reason for re-formatting if:
               DVD-RW was deformatted by -blank,
               DVD+RW has read failures (re-format before next write),
               DVD-RAM or BD-RE shall change their amount of defect reserve.
              BD-R  may  be written unformatted or may be formatted before first use.  Formatting
              activates Defect Management which tries to catch and  repair  bad  spots  on  media
              during the write process at the expense of half speed even with flawless media.
              The  progress reports issued by some drives while formatting are quite unrealistic.
              Do not conclude success or failure from the reported  percentages.  Formatting  was
              successful  if  no SORRY event or worse occurred. Be patient with apparently frozen

              Put out a list of format descriptors as  reported  by  the  output  drive  for  the
              current  medium.  The  list gives the index number after "Format idx", a MMC format
              code, the announced size in blocks (like "2236704s") and the same size in MiB.
              MMC format codes are manifold. Most important are: "00h" general formatting,  "01h"
              increases reserve space for DVD-RAM, "26h" for DVD+RW, "30h" for BD-RE with reserve
              space, "31h" for BD-RE without reserve space, "32h" for BD-R.
              Smaller format size with DVD-RAM, BD-RE, or BD-R means more reserve space.

              Put out a list of speed values as reported by the drives with the loaded media. The
              list tells read speeds of the input drive and of the output drive. Further it tells
              write speeds of the output drive.
              The list of write speeds does not necessarily mean that the medium is  writable  or
              that these speeds are actually achievable. Especially the lists reported with empty
              drive or with ROM media obviously advertise speeds for other media.
              It is not mandatory to use speed values out of the  listed  range.   The  drive  is
              supposed to choose a safe speed that is as near to the desired speed as possible.
              At  the  end  of the list, "Write speed L" and "Write speed H" are the best guesses
              for lower and upper write speed limit.  "Write speed l" and  "Write  speed  h"  may
              appear only with CD and eventually override the list of other speed offers.
              Only  if the drive reports contradicting speed information there will appear "Write
              speed 0", which tells the outcome of speed selection by command  -speed  0,  if  it
              deviates from "Write speed H".
              "Read  speed  L"  and  "Read  speed H" tell the minimum and maximum read speeds, as
              reported by the drive. They would be chosen by -read_speed "min" or "max"  if  they
              undercut  or  surpass  the  built-in  limits.  These  are  "1x", "52xCD", "24xDVD",

       -close_damaged "as_needed"|"force"
              Try to close the upcoming track and session if the drive  reported  the  medium  as
              damaged.  This  may  apply  to CD-R, CD-RW, DVD-R, DVD-RW, DVD+R, DVD+R DL, or BD-R
              media. It is indicated by warning messages when the drive gets acquired, and  by  a
              remark "but next track is damaged" with the line "Media status :" of command -toc.
              The setting of command -close determines whether the medium stays appendable.
              Mode  "as_needed"  gracefully  refuses  on media which are not reported as damaged.
              Mode "force" attempts the close operation even with media which appear undamaged.
              No image changes are allowed to be pending before this command is performed.  After
              closing was attempted, both drives are given up.

       -list_profiles "in"|"out"|"all"
              Put  out a list of media types supported by -indev, -outdev, or both, respectively.
              The currently recognized type is marked by text "(current)".

       Settings for result writing:

       Rock Ridge info will be generated by default.  ACLs  will  be  written  according  to  the
       setting of command -acl.

       -joliet "on"|"off"
              If enabled by "on", generate Joliet tree additional to ISO 9660 + Rock Ridge tree.

       -hfsplus "on"|"off"
              If  enabled  by "on", generate a 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
              This  may  collide  with  data  submitted by -boot_image system_area=.  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.
              The   HFS+  filesystem  is  not  suitable  for  add-on  sessions  produced  by  the
              multi-session method of growing. An existing ISO image may nevertheless be the base
              for  a  new image produced by the method of modifying.  If -hfsplus is enabled when
              -indev or -dev gets executed, then AAIP attributes get loaded from the input  image
              and  checked  for  information  about HFS creator, filetype, or blessing. If found,
              then they get enabled as settings for the next image production.  Therefore  it  is
              advisable to perform -hfsplus "on" before -indev or -dev.
              Information  about  HFS  creator,  type,  and  blessings  gets stored by xorriso if
              -hfsplus is enabled at -commit  time.  It  is  stored  as  copy  outside  the  HFS+
              partition, but rather along with the Rock Ridge information.  xorriso does not read
              any information from the HFS+ meta data.
              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_...".

       -rockridge "on"|"off"
              Mode "off" disables production of Rock Ridge information  for  the  ISO  9660  file
              objects.  The  multi-session  capabilities  of  xorriso  depend  much on the naming
              fidelity of Rock Ridge. So it is  strongly  discouraged  to  deviate  from  default
              setting "on".

       -compliance rule[:rule...]
              Adjust  the  compliance to specifications of ISO 9660/ECMA-119 and its contemporary
              extensions. In some cases it is worth to deviate a bit in order to circumvent  bugs
              of the intended reader system or to get unofficial extra features.
              There are several adjustable rules which have a keyword each. If they are mentioned
              with this command then their rule gets added to the relaxation list. This list  can
              be  erased  by  rules  "strict" or "clear". It can be reset to its start setting by
              "default". All of the following relaxation rules can  be  revoked  individually  by
              appending "_off". Like "deep_paths_off".
              Rule keywords are:
              "iso_9660_level="number  chooses  level  1  with ECMA-119 names of the form 8.3 and
              -file_size_limit <= 4g - 1, or level 2 with ECMA-119 names up to length 32 and  the
              same  -file_size_limit,  or  level  3  with  ECMA-119  names  up  to  length 32 and
              -file_size_limit >= 400g -200k. If necessary -file_size_limit gets adjusted.
              "allow_dir_id_ext" allows ECMA-119 names of directories to have a name extension as
              with  other  file  types.  It  does not force dots and it omits the version number,
              though. This is a bad tradition of mkisofs which violates ECMA-119.  Especially ISO
              level 1 only allows 8 characters in a directory name and not 8.3.
              "omit_version" does not add versions (";1") to ECMA-119 and Joliet file names.
              "only_iso_version" does not add versions (";1") to Joliet file names.
              "deep_paths" allows ECMA-119 file paths deeper than 8 levels.
              "long_paths" allows ECMA-119 file paths longer than 255 characters.
              "long_names" allows up to 37 characters with ECMA-119 file names.
              "no_force_dots" does not add a dot to ECMA-119 file names which have none.
              "no_j_force_dots" does not add a dot to Joliet file names which have none.
              "lowercase" allows lowercase characters in ECMA-119 file names.
              "7bit_ascii"  allows  nearly  all  7-bit  characters  in  ECMA-119 file names.  Not
              allowed are 0x0 and '/'. If not "lowercase" is enabled, then lowercase letters  get
              converted to uppercase.
              "full_ascii" allows all 8-bit characters except 0x0 and '/' in ECMA-119 file names.
              "untranslated_names"  might  be dangerous for inadverted reader programs which rely
              on the restriction to at most 37 characters in  ECMA-119  file  names.   This  rule
              allows  ECMA-119  file names up to 96 characters with no character conversion. If a
              file name has more characters, then image production will fail deliberately.
              "untranslated_name_len="number enables untranslated_names with a smaller limit  for
              the length of file names. 0 disables this feature, -1 chooses maximum length limit,
              numbers larger than 0 give the desired length limit.
              "joliet_long_names" allows Joliet leaf names up to 103 characters rather than 64.
              "joliet_long_paths" allows Joliet paths longer than 240 characters.
              "joliet_utf16" encodes Joliet 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.
              "always_gmt" stores timestamps in GMT representation with timezone 0.
              "rec_mtime" records with non-RockRidge directory entries the disk file's mtime  and
              not  the  creation  time of the image. This applies to the ECMA-119 tree (plain ISO
              9660), to Joliet, and to ISO 9660:1999. "rec_time" is default. If disabled, it gets
              automatically re-enabled by -as mkisofs emulation when a pathspec is encountered.
              "new_rr"  uses  Rock  Ridge  version 1.12 (suitable for GNU/Linux but not for older
              FreeBSD or for Solaris). This implies "aaip_susp_1_10_off" which may be changed  by
              subsequent "aaip_susp_1_10".
              Default  is  "old_rr"  which  uses  Rock  Ridge  version  1.10.  This  implies also
              "aaip_susp_1_10" which may be changed by subsequent "aaip_susp_1_10_off".
              "aaip_susp_1_10" allows AAIP to be written as unofficial extension of  RRIP  rather
              than as official extension under SUSP-1.12.
              "no_emul_toc"  saves  64 kB with the first session on overwriteable media but makes
              the image incapable of displaying its session history.
              "iso_9660_1999" causes the production of an additional directory tree compliant  to
              ISO  9660:1999.  It  can  record long filenames for readers which do not understand
              Rock Ridge.
              "old_empty" uses 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.
              Default setting is
              Note: The term "ECMA-119 name" means the plain ISO 9660 names and attributes  which
              get visible if the reader ignores Rock Ridge.

       -rr_reloc_dir name
              Specify the name of the relocation directory in which deep directory subtrees shall
              be placed if -compliance is set to "deep_paths_off" or  "long_paths_off".   A  deep
              directory  is  one  that has a chain of 8 parent directories (including root) above
              itself, or one that contains a  file  with  an  ECMA-119  path  of  more  than  255
              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
              The  default relocation directory is the root directory. By giving a non-empty name
              with -rr_reloc_dir, a directory in the root directory may get this role.   If  that
              directory  does  not  already  exist  at -commit time, 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 and must not be longer than 255 bytes.

       -volid text
              Specify  the volume ID, which most operating systems will consider to be the volume
              name of the image or medium.
              xorriso accepts any text up to 32 characters, but according to rarely obeyed  specs
              stricter rules apply:
              ECMA-119 demands ASCII characters out of [A-Z0-9_]. Like:
              Joliet allows 16 UCS-2 characters. Like:
                "Windows name"
              Be  aware  that the volume id might get used automatically as the name of the mount
              point when the medium is inserted into a playful computer system.
              If an ISO image gets loaded while the volume ID is set to default "ISOIMAGE" or  to
              "",  then the volume ID of the loaded image will become the effective volume id for
              the next write run. But as soon as command -volid  is  performed  afterwards,  this
              pending ID is overridden by the new setting.
              Consider  this  when  setting  -volid  "ISOIMAGE" before executing -dev, -indev, or
              -rollback.  If you insist in -volid "ISOIMAGE", set it again after those commands.

       -volset_id text
              Set the volume set ID string to be written with the next -commit.  Permissible  are
              up to 128 characters. This setting gets overridden by image loading.

       -publisher text
              Set  the publisher ID string to be written with the next -commit. This may identify
              the person or organisation who specified what shall be recorded.   Permissible  are
              up to 128 characters. This setting gets overridden by image loading.

       -application_id text
              Set  the  application  ID  string  to  be  written  with the next -commit. This may
              identify the specification of how the data are recorded.  Permissible are up to 128
              characters. This setting gets overridden by image loading.
              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.

       -system_id text
              Set the system ID string to be written with the next -commit. 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. This setting gets overridden
              by image loading.

       -volume_date type timestring
              Set one of the four overall timestamps for  subsequent  image  writing.   Available
              types are:
              "c"  time when the volume was created.
              "m"  time when volume was last modified.
              "x"  time when the information in the volume expires.
              "f"  time since when the volume is effectively valid.
              "all_file_dates"   sets mtime, atime, and ctime of all files and directories to the
              given time. If the timestring is "set_to_mtime", then the atime and ctime  of  each
              file and directory get set to the value found in their mtime.
              These actions stay delayed until actual ISO production begins.  Up to then they can
              be revoked by "all_file_dates" with empty timestring or timestring "default".
              The timestamps of the El Torito boot catalog file get refreshed  when  the  ISO  is
              produced. They can be influenced by "uuid".
              "uuid"   sets  a timestring that overrides "c" and "m" times literally and sets the
              time of the El Torito boot catalog.  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).
              Timestrings for the other types may be given as with command -alter_date.  Some  of
              them  are prone to timezone computations. The timestrings "default" or "overridden"
              cause default settings: "c" and "m" will show the current time of  image  creation.
              "x" and "f" will be marked as insignificant.  "uuid" will be deactivated.
              At  -commit  time,  some  timestamps  get  set  to the maximum value of effectively
              written volume creation  and  modification  time:  El  Torito  boot  catalog,  HFS+
              superblock,  ECMA-119  file  modification  time if -compliance "no_rec_mtime".  The
              isohybrid MBR id is computed from "uuid" if given, else from the  effective  volume
              modification date.

       -copyright_file text
              Set the copyright file name to be written with the next -commit. This should be the
              ISO 9660 path of a  file  in  the  image  which  contains  a  copyright  statement.
              Permissible are up to 37 characters. This setting gets overridden by image loading.

       -abstract_file text
              Set  the abstract file name to be written with the next -commit. 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. This setting gets overridden
              by image loading.

       -biblio_file text
              Set the biblio file name to be written with the next -commit. This  should  be  the
              ISO  9660  path  of  a  file  in  the  image  which contains bibliographic records.
              Permissible are up to 37 characters. This setting gets overridden by image loading.

              Set the preparer ID string to be written with the next -commit. 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.
              Unlike other ID strings, this setting is not influenced by image loading.

       -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.
              This setting is not influenced by image loading.

       -out_charset character_set_name
              Set the character set to which file names get converted when writing an image.  See
              paragraph  "Character  sets" for more explanations.  When loading the written image
              after -commit the setting of -out_charset will be copied to -in_charset.

       -uid uid
              User id to be used for all files when the new ISO tree gets written to media.

       -gid gid
              Group id to be used for all files when the new ISO tree gets written to media.

       -zisofs option[:options]
              Set global parameters for zisofs compression. This data format  is  recognized  and
              transparently  uncompressed  by some Linux kernels. It is to be applied via command
              -set_filter with built-in filter "--zisofs".  Parameters are:
               "level="[0-9] zlib compression: 0=none, 1=fast,..., 9=slow
               "block_size="32k|64k|128k size of compression blocks
               "by_magic=on" enables an expensive test at  image  generation  time  which  checks
              files  from  disk  whether  they  already  are  zisofs  compressed, e.g. by program
               "default" same as "level=6:block_size=32k:by_magic=off"

       -speed code|number[k|m|c|d|b]
              Set the burn speed. Default is "max" (or "0") = maximum speed as announced  by  the
              drive.  Further special speed codes are:
              "min" (or "-1") selects minimum speed as announced by the drive.
              "none" avoids to send a speed setting command to the drive before burning begins.
              Speed can be given in media dependent numbers or as a desired throughput per second
              in MMC compliant kB (= 1000) or MB (= 1000 kB). Media x-speed  factor  can  be  set
              explicitly by "c" for CD, "d" for DVD, "b" for BD, "x" is optional.
              Example speeds:
               706k = 706kB/s = 4c = 4xCD
               5540k = 5540kB/s = 4d = 4xDVD
              If  there  is no hint about the speed unit attached, then the medium in the -outdev
              will decide. Default unit is CD = 176.4k.
              MMC drives usually activate their own idea of speed and take the speed value  given
              by the burn program only as upper limit for their own decision.

       -stream_recording "on"|"off"|"full"|"data"|number
              Setting  "on"  tries  to circumvent the management of defects on DVD-RAM, BD-RE, or
              BD-R. Defect management keeps partly damaged media usable.  But  it  reduces  write
              speed  to  half nominal speed even if the medium is in perfect shape.  For the case
              of flawless media, one may use -stream_recording "on" to get full speed.
              "full" tries full speed with all write operations,  whereas  "on"  does  this  only
              above  byte  address  32s. One may give a number of at least 16s in order to set an
              own address limit.
              "data" causes full speed to start when superblock and directory entries are written
              and writing of file content blocks begins.

       -dvd_obs "default"|"32k"|"64k"
              GNU/Linux  specific:  Set  the  number  of  bytes to be transmitted with each write
              operation to DVD or BD media. A number of 64 KB may  improve  throughput  with  bus
              systems  which show latency problems. The default depends on media type, on command
              -stream_recording , and on compile time options.

       -modesty_on_drive parameter[:parameters]
              Control whether the drive buffer shall be  kept  from  getting  completely  filled.
              Parameter  "on" (or "1") keeps the program from trying to write to the burner drive
              while its buffer is in danger to be filled over a given limit.  If  this  limit  is
              exceeded  then  the  program  will  wait  until  the  filling  reaches  a given low
              percentage value.
              This can ease the load on operating system and drive controller and thus help  with
              achieving  better  input  bandwidth  if  disk  and  burner  are  not on independent
              controllers (like hda and hdb). It  may  also  help  with  throughput  problems  of
              simultaneous  burns  on  different burners with Linux kernels like 3.16, if one has
              reason not to fix the problem by -scsi_dev_family  "sg".   On  the  other  hand  it
              increases the risk of buffer underflow and thus reduced write speed.
              Some  burners are not suitable because they report buffer fill with granularity too
              coarse in size or time, or expect their buffer to be filled to the top before  they
              go to full speed.
              Parameters "off" or "0" disable this feature.
              The  threshold  for  beginning  to  wait  is  given  by  parameter  "max_percent=".
              Parameter  "min_percent="  defines  the  threshold   for   resuming   transmission.
              Percentages  are  permissible  in  the  range  of  25 to 100. Numbers in this range
              without a prepended name are interpreted as "on:min_percent=".
              E.g.: -modesty_on_drive 75
              The optimal values depend on the buffer behavior of the drive.
              Parameter "timeout_sec=" defines after  which  time  of  unsuccessful  waiting  the
              modesty shall be disabled because it does not work.
              Parameter  "min_usec=" defines the initial sleeping period in microseconds.  If the
              drive buffer appears to be too full for sending more data, the  program  will  wait
              the  given time and inquire the buffer fill state again.  If repeated inquiry shows
              not enough free space, the sleep time will slowly be increased  to  what  parameter
              "max_usec=" defines.
              Parameters,  which  are  not  mentioned  with  a  -modesty_on_drive  command,  stay
              unchanged.  Default is:
                -modesty_on_drive off:min_percent=90:max_percent=95:

       -use_immed_bit "on"|"off"|"default"
              Control whether several long lasting SCSI commands shall be executed with the Immed
              bit,  which  makes  the commands end early while the drive operation is still going
              on. xorriso then inquires progress indication until the drive reports to  be  ready
              again.  If  this  feature  is turned off, then blanking and formatting will show no
              progress indication.
              It may depend on the operating system whether -use_immed_bit is  set  to  "off"  by
              default.  Command  -status  will  tell  by appending "/on" or "/off" if a drive has
              already been acquired and -use_immed_bit is currently set  to  "default".   Command
              -use_immed_bit tolerates and ignores such appended text.

       -stdio_sync "on"|"off"|"end"|number
              Set  the number of bytes after which to force output to stdio: pseudo drives.  This
              forcing keeps the memory from being clogged with lots  of  pending  data  for  slow
              devices.  Default  "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.

       -dummy "on"|"off"
              If  "on"  then  simulate  burning  or refuse with FAILURE event if no simulation is
              possible, do neither blank nor format.

       -fs number["k"|"m"]
              Set the size of the fifo buffer which smoothens the  data  stream  from  ISO  image
              generation  to media burning. Default is 4 MiB, minimum 64 kiB, maximum 1 GiB.  The
              number may be followed by letter "k" or "m" which means unit is kiB (= 1024) or MiB
              (= 1024 kiB).

       -close "on"|"off"|"as_needed"
              If  -close  is set to "on" then mark the written medium as not appendable any more.
              This will have no effect on overwritable media types.  Setting "on" is the contrary
              of cdrecord option -multi, and is one aspect of growisofs option -dvd-compat.
              If set to "off" then keep the medium writable for an appended session.
              If  set  to  "as_needed"  then use "on" only if "off" is predicted to fail with the
              given medium and its state.
              Not all drives correctly recognize fast-blanked DVD-RW which need "on".   If  there
              is  well  founded suspicion that a burn run failed due to -close "off", then -close
              "as_needed" causes a re-try with "on".
              Note that emulation  command  -as  "cdrecord"  temporarily  overrides  the  current
              setting of -close by its own default -close "on" if its option -multi is missing.

       -write_type "auto"|"tao"|"sao/dao"
              Set  the  write  type  for  the next burn run. "auto" will select SAO with blank CD
              media, DAO with blank DVD-R[W] if -close is  "on",  and  elsewise  CD  TAO  or  the
              equivalent  write  type  of  the  particular DVD/BD media.  Choosing TAO or SAO/DAO
              explicitly might cause the burn run to fail  if  the  desired  write  type  is  not
              possible with the given media state.

       -padding number["k"|"m"]|"included"|"appended"
              Append  the given number of extra bytes to the image stream.  This is a traditional
              remedy for a traditional bug in block device  read  drivers.  Needed  only  for  CD
              recordings  in TAO mode.  Since one can hardly predict on what media an image might
              end up, xorriso adds the traditional 300k of padding by default to all images.
              For images which will never get to a CD it is safe to use -padding 0 .
              Normally padding is not written as part of the ISO image  but  appended  after  the
              image end. This is -padding mode "appended".
              Emulation  command  -as "mkisofs" and command -jigdo cause padding to be written as
              part of the image.  The same effect is achieved by -padding mode "included".

       Bootable ISO images:

       Contrary to published specifications many BIOSes will load an El Torito  record  from  the
       first  session  on  media  and  not from the last one, which gets mounted by default. This
       makes no problems with overwriteable media, because they appear to inadverted  readers  as
       one single session.
       But  with multi-session media CD-R[W], DVD-R[W], DVD+R, it implies that the whole bootable
       system has to reside already in the first session and that the last session still  has  to
       bear all files which the booted system expects after mounting the ISO image.
       If  a  boot image from ISOLINUX or GRUB is known to be present on media then it is advised
       to patch it when a follow-up session  gets  written.  But  one  should  not  rely  on  the
       capability  to  influence  the bootability of the existing sessions, unless one can assume
       overwriteable media.
       Normally the boot images are data  files  inside  the  ISO  filesystem.  By  special  path
       "--interval:appended_partition_NNN:all::"   it   is  possible  to  refer  to  an  appended
       partition. The number NNN gives the  partition  number  as  used  with  the  corresponding
       command -append_partition.  E.g.:
         -append_partition 2 0xef /tmp/efi.img
         -boot_image any efi_path=--interval:appended_partition_2:all::
       There  are booting mechanisms which do not use an El Torito record but rather start at the
       first bytes of the image: PC-BIOS MBR or EFI GPT for hard-disk-like devices, APM partition
       entries  for Macs which expect HFS+ boot images, MIPS Volume Header for old SGI computers,
       DEC Boot Block for old MIPS DECstation, SUN Disk Label  for  SPARC  machines,  HP-PA  boot
       sector for HP PA-RISC machines, DEC Alpha SRM boot sector for old DEC Alpha machines.

       Several  of  the following commands 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:  command  -append_partition, boot specs
       system_area=, grub2_mbr=, prep_boot_part=, efi_boot_part=.
       The description string consists of the following components, separated by colon ':'
       The component "--interval" states that this is  not  a  plain  disk  path  but  rather  an
       interval   reader   description   string.    The  component  Flags  modifies  the  further
       "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.
       "appended_partition_NNN"  with  a  decimal number NNN works only for -boot_image bootspecs
       which announce El Torito boot image paths: bin_path=, efi_path=.   The  number  gives  the
       partition number as used with the corresponding command -append_partition.
       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
       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".

       -boot_image "any"|"isolinux"|"grub"
              Define the equipment of the emerging filesystem with boot entry points.
              With systems which boot via BIOS or EFI this is a set of  El  Torito  boot  images,
              possibly  MBR  boot  code,  and possibly partition tables of type MBR, GPT, or APM.
              Such file sets get produced by boot loader systems like ISOLINUX or GRUB.

              Each -boot_image command has two  parameters:  type  and  setting.  More  than  one
              -boot_image  command may be used to define the handling of one or more boot images.
              Sequence matters.
              Types  isolinux  and  grub  care  for  known  peculiarities.   Type  any  makes  no
              assumptions about the origin of the boot images.

              When  loading  an ISO filesystem, system area and El Torito boot images get loaded,
              too. The default behavior is not to write loaded El Torito boot images and to write
              the loaded system area content without alterations.
              discard  gives  up  the  El  Torito  boot  catalog and its boot images.  regardless
              whether loaded from an ISO filesystem or defined by  commands.   Any  BIOS  or  EFI
              related  boot  options  get  revoked.   Nevertheless,  loaded system area data stay
              valid. If desired, they have to be erased by
               -boot_image any system_area=/dev/zero
              keep keeps or copies El Torito boot images unaltered and writes a new catalog.
              patch applies patching to existing El Torito boot images if they  seem  to  bear  a
              boot info table.
              A  boot  info  table  needs to be patched when the boot image gets newly introduced
              into the ISO image or if an existing image gets relocated.  This  is  automatically
              done if type "isolinux" or "grub" is given, but not with "any".
              If  patching  is  enabled,  then boot images from previous sessions will be checked
              whether they seem to bear a boot info table. If not, then they stay unpatched. This
              check  is  not  infallible. So if you do know that the images need no patching, use
              "any" "keep".  "grub" "patch" will not patch EFI images (platform_id=0xef).
              replay is a more modern version of "patch", which not only cares  for  existing  El
              Torito  boot  equipment but also for the recognizable boot provisions in the System
              Area. It discards any  existing  -boot_image  setting  and  executes  the  commands
              proposed by command -report_el_torito "cmd".
              This  action  will  only  succeed  if  the  file objects mentioned in the output of
              command -report_el_torito "cmd" are still available. Do not remove or  rename  boot
              image files after -indev.
              Drop unknown El Torito:  -boot_image "any" "discard"
              Maintain recognizable stuff:  -boot_image "any" "replay"
              El Torito only for GRUB:  -boot_image "grub" "patch"
              El Torito only for ISOLINUX:  -boot_image "isolinux" "patch"
              show_status  will  print  what  is  known  about  the  loaded boot images and their
              designated fate.

              A bootspec is a word of the form name=value. It is used to describe the  parameters
              of  a  boot  feature.   The  names  "dir", "bin_path", "efi_path" lead to El Torito
              bootable images.  Name "system_area" activates a given file as MBR  or  other  disk
              On  all  media types this is possible within the first session. In further sessions
              an existing boot image can get replaced by a new one, but depending  on  the  media
              type this may have few effect at boot time. See above.
              El  Torito  boot  images  have  to be added to the ISO image by normal means (image
              loading, -map, -add, ...). In case of ISOLINUX the files should  reside  either  in
              ISO  image  directory /isolinux or in /boot/isolinux .  In that case it suffices to
              use as bootspec the text "dir=/isolinux" or "dir=/boot/isolinux". E.g.:
               -boot_image isolinux dir=/boot/isolinux
              which bundles these individual settings:
               -boot_image isolinux bin_path=/boot/isolinux/isolinux.bin
               -boot_image isolinux cat_path=/boot/isolinux/
               -boot_image isolinux load_size=2048
               -boot_image any boot_info_table=on
              An El Torito boot catalog file gets  inserted  into  the  ISO  image  with  address
              cat_path=  with  the  first  -boot_image  "any"  "next"  or at -commit time.  It is
              subject to normal -overwrite and -reassure processing if there is  already  a  file
              with  the  same  name.   The  catalog lists the boot images and is read by the boot
              facility to choose one of the boot images. But it is not necessary that it  appears
              in the directory tree at all. One may hide it in all trees by cat_hidden=on.  Other
              possible values are "iso_rr", "joliet", "hfsplus",  and  the  default  "off".   The
              timestamps  of  the  boot  catalog  file  are  refreshed  at  commit time.  Command
              -volume_date "uuid" can be used to set their value.
              bin_path= depicts an El Torito boot image file, a binary program  which  is  to  be
              started by the hardware boot facility (e.g. the BIOS) at boot time.
              efi_path=  depicts an El Torito boot image file that is ready for EFI booting. This
              is normally a FAT filesystem image not larger than 65535 blocks of 512 bytes (=  32
              MiB  -  512).   Its  load_size is determined automatically, no boot info table gets
              written, no boot medium gets emulated, platform_id is 0xef.
              emul_type= can be one of "no_emulation", "hard_disk", "diskette".  It controls  the
              boot medium emulation code of a boot image.  The default "no_emulation" is suitable
              for ISOLINUX, GRUB, FreeBSD cdboot.
              load_size= is a value which depends on the  boot  image.   Default  is  2048  which
              matches  the  expectations of most boot images.  The special value "full" means the
              full size of the boot image file rounded up to a multiple of 2048 bytes. Maximum is
              33,552,384 bytes.
              boot_info_table=on causes address patching to bytes 8 to 63 of the boot image which
              is given by "any" "bin_path=".  "boot_info_table=off" disables this patching.
              grub2_boot_info=on causes address patching to byte 2548 of the boot image which  is
              given by "any" "bin_path=".  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.  "grub2_boot_info=off" disables this patching.
              platform_id= defines by a hexadecimal or decimal number the Platform ID of the boot
              image. "0x00" is 80x86 PC-BIOS, "0x01" is PowerPC, "0x02" is  Mac,  "0xef"  is  EFI
              (decimal "239").
              id_string=text|56_hexdigits defines 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.
              sel_crit=hexdigits  defines  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.
              next  ends  the  definition  of  a  boot image and starts a new one.  Any following
              -bootimage bootspecs will affect the new image.  The first "next"  discards  loaded
              boot images and their catalog.
              system_area=disk_path  copies  at  most 32768 bytes from the given disk file to the
              very start of the ISO image.  This System Area is  reserved  for  system  dependent
              boot software, e.g. an MBR which can be used to boot from USB stick or hard disk.
              Other than an El Torito boot image, the file disk_path needs not to be added to the
              ISO image.
              -boot_image isolinux system_area= implies "partition_table=on".  In this case,  the
              disk  path  should  lead to one of the SYSLINUX files isohdp[fp]x*.bin or to a file
              which was derived from one of those files.  E.g. to the first  512  bytes  from  an
              ISOLINUX isohybrid ISO image.
              In  this  case, El Torito boot images (dir=, bin_path=, efi_path=) may be augmented
              by isolinux partition_entry=gpt_basdat or isolinux partition_entry=gpt_hfsplus, and
              by  isolinux partition_entry=apm_hfsplus.  The boot image will then be mentioned in
              GPT as Basic Data or GPT HFS+ partition, and in APM as HFS+ partition.   The  first
              three GPT partitions will also be marked by MBR partitions.
              In  multi-session  situations the existing System Area is preserved by default.  In
              in this case, the special disk_path  "."  prevents  reading  of  a  disk  file  but
              nevertheless  causes  adjustments  in the loaded system area data. Such adjustments
              may get ordered by -boot_image commands.
              -boot_image any gpt_disk_guid=value controls whether an emerging GPT  shall  get  a
              randomly  generated  disk  GUID or whether the GUID is supplied by the user.  Value
              "random" is default. Value "volume_date_uuid" produces a low quality GUID from  the
              value set by -volume_date "uuid".
              A  string  of 32 hex digits, or a RFC 4122 compliant GUID string may be used to set
              the disk GUID directly. UEFI prescribes the first three components of  a  RFC  4122
              GUID string to be byte-swapped in the binary representation:
              E.g.            gpt_disk_guid=2303cd2a-73c7-424a-a298-25632da7f446           equals
              The partition GUIDs get generated by minimally varying the disk GUID.
              -boot_image    any    part_like_isohybrid=on    enables    -boot_image     isolinux
              partition_entry=  even  if  no  -boot_image isolinux system_area= is given.  No MBR
              partition  of type 0xee emerges, even if GPT gets produced.  Gaps between  GPT  and
              APM  partitions  will  not  be  filled by more partitions.  Appended partitions get
              mentioned in APM if other APM partitions emerge.
              -boot_image any  iso_mbr_part_type=number  sets  the  partition  type  of  the  MBR
              partition which represents the ISO or at least protects it.
              Number  may be 0x00 to 0xff. The text "default" re-enables the default types of the
              various occasions to create an ISO MBR partition.  This is  without  effect  if  no
              such  partition  emerges  by  other settings or if the partition type is prescribed
              mandatorily like 0xee for GPT protective MBR or 0x96 for CHRP.
              If   instead   a   type_guid   is   given   by   a   32-digit   hex   string   like
              a2a0d0ebe5b9334487c068b6b72699c7     or     by     a     structured    text    like
              EBD0A0A2-B9E5-4433-87C0-68B6B72699C7, then it will be used as partition type if the
              ISO     filesystem     appears     as     partition     in     GPT.      In    MBR,
              C12A7328-F81F-11D2-BA4B-00A0C93EC93B will be mapped to 0xef.  Any other  GUID  will
              be mapped to 0x83.
              grub2_mbr=disk_path  works  like  "any"  system_area=  with additional patching for
              modern GRUB MBRs. 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.
              This feature can be revoked either by  grub2_mbr=  with  empty  disk  path,  or  by
              submitting a disk_path via system_area=.
              partition_table=on  causes a simple partition table to be written into bytes 446 to
              511 of the System Area.
              With type "isolinux" it shows a partition that begins at byte 0 and it  causes  the
              LBA  of the first boot image to be written into the MBR. For the first session this
              works only if also "system_area=" and "bin_path=" or "dir=" is given.
              With types "any" and "grub" it shows a single partition which starts  at  byte  512
              and ends where the ISO image ends.  This works with or without system_area= or boot
              Bootspecs chrp_boot_part=, prep_boot_part=, and efi_boot_part= overwrite this entry
              in the MBR partition table.
              If  types  "isolinux"  or  "grub"  are set to "patch", then "partition_table=on" is
              activated without new boot image.  In this  case  the  existing  System  Area  gets
              checked  whether  it  bears  addresses  and  sizes  as  if it had been processed by
              "partition_table=on". If so, then those parameters get updated when the new  System
              Area is written.
              Special  "system_area=/dev/zero"  causes  32k of NUL-bytes.  Use this to discard an
              MBR which was loaded with the ISO image.
              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.
              appended_part_as=mbr is the default. Appended partitions get marked in GPT only  if
              GPT  is  produced  because  of  other  settings.   If given explicitly, this clears
              setting "gpt" and "apm". Nevertheless "apm" may be added to "mbr".
              appended_part_as=apm marks partitions from -append_partition in APM additionally to
              "mbr" or "gpt".
              By  default,  appended partitions get marked in APM only if APM is produced because
              of other options together with part_like_isohybrid="on".
              chrp_boot_part=on causes a single partition in MBR which covers the whole ISO image
              and  has type 0x96. This is not compatible with any other feature that produces MBR
              partition entries. It makes GPT unrecognizable.
              prep_boot_part=disk_path inserts the content of a data  file  into  the  image  and
              marks  it  by  an MBR partition of type 0x41. The parts of the ISO image before and
              after this partition will be covered by further MBR partitions.  The data  file  is
              supposed to contain ELF executable code.
              efi_boot_part=disk_path inserts the content of a data file into the image and marks
              it by a GPT partition. If not chrp_boot_part=on, then the first  partition  in  MBR
              will  have type 0xee to announce the presence of GPT.  The data file is supposed to
              contain a FAT filesystem.
              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 bootspec efi_path=.  The affected EFI  boot  image  cannot
              show up in HFS+ because it is stored outside the HFS+ partition.
              partition_offset=2kb_block_adr  causes  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. 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.   So
              the value defined here is only in effect if a new ISO image gets written.
              partition_hd_cyl=number  gives  the  number of heads per cylinder for the partition
              table. 0 chooses a default value. Maximum is 255.
              partition_sec_hd=number gives the number of sectors  per  head  for  the  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.
              partition_cyl_align=mode  controls  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  with  "isolinux"
              Mode "on" causes alignment by padding with "partition_table=on" for any type.  Mode
              "all" is like "on" but also pads up partitions from -append_partition to an aligned
              Mode "off" disables alignment for any type.
              mbr_force_bootable=mode  enforces  an  MBR partition with "bootable/active" flag if
              options like partition_table= or grub2_mbr= indicate production of a bootable  MBR.
              These  options  normally  cause  the flag to be set if there is an MBR partition of
              type other than 0xee or 0xef.  If no such partition exists,  then  no  bootflag  is
              set,  unless  mbr_force_bootable="on"  forces creation of a dummy partition of type
              0x00 which covers only the first block of the ISO image.
              If no bootable MBR is indicated and a partition gets created by  -append_partition,
              then  mbr_force_bootable="on"  causes  a  bootflag like it would do with a bootable
              mips_path=iso_rr_path declares a data file in the image to be  a  MIPS  Big  Endian
              boot  file  and  causes  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 system_area=.  Up to 15 boot
              files can be declared by mips_path=.
              mipsel_path=iso_rr_path declares 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 system_area=.  Only a  single
              boot file can be declared by mipsel_path=.
              sparc_label=text  causes  the production of a SUN Disk Label with the given text as
              ASCII label. Partitions 2 to 8 may be occupied by  appended  images.   Partition  1
              will  always  be the ISO image. See command -append_partition.  The first 512 bytes
              of any data provided by system_area= will be overwritten.
              grub2_sparc_core=iso_rr_path causes the content address and size of the given  file
              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  sets  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_  bootspecs  are  mandatory,  if  any  of  the  hppa_
              bootspecs is used. Only hppa_hdrversion= is allowed to be missing.
              hppa_bootloader=iso_rr_path designates the given path as HP-PA bootloader file.
              hppa_kernel_32=iso_rr_path designates the given path as HP-PA 32 bit kernel file.
              hppa_kernel_64=iso_rr_path designates the given path as HP-PA 64 bit kernel file.
              hppa_ramdisk=iso_rr_path designates the given path as HP-PA RAM disk file.
              hppa_hdrversion=number  chooses between PALO header version 5 (default) and version
              4.  For the appropriate value see in PALO source code: PALOHDRVERSION.
              alpha_boot=iso_rr_path declares a data file in the image to be the  DEC  Alpha  SRM
              Secondary  Bootstrap  Loader and causes production of a boot sector which points to
              it.  This is mutually exclusive with production of other boot blocks like MBR.
              mips_discard, sparc_discard,  hppa_discard,  alpha_discard  revoke  any  boot  file
              declarations  made  for  mips/mipsel,  sparc,  hppa,  or alpha, respectively.  This
              removes the ban on production of other boot blocks.
              hfsplus_serial=hexstring sets 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  sets the allocation block size to be used when producing
              HFS+ filesystems. Permissible are 512, 2048, or 0.  The  latter  lets  the  program
              apm_block_size=number  sets 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.

       -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
              Partitions may be appended with boot block type MBR and with SUN Disk Label.
              With MBR:
              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 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 MBR
              partition type codes search the Internet for "Partition Types" or run fdisk command
              type_code    may    also    be   a   type   GUID   as   plain   hex   string   like
              a2a0d0ebe5b9334487c068b6b72699c7     or      as      structured      text      like
              EBD0A0A2-B9E5-4433-87C0-68B6B72699C7. It will be used if the partition is mentioned
              in GPT. In MBR, C12A7328-F81F-11D2-BA4B-00A0C93EC93B will be mapped  to  0xef.  Any
              other GUID will be mapped to 0x83.
              If  some  other  command causes the production of GPT, then the appended partitions
              will be mentioned there too.
              The disk_path must provide the necessary data  bytes  at  commit  time.   An  empty
              disk_path disables this feature for the given partition number.
              With SUN Disk Label (selected by -boot_image any sparc_label=):
              partition_number  may  be 2 to 8. Number 1 will always be the ISO image.  Partition
              start addresses are aligned to 320 KiB. The type_code does not matter. Submit 0x0.
              Partition image name "." causes the partition to become a copy of  the  next  lower
              valid one.

       Jigdo Template Extraction:

       From  man genisoimage: "Jigdo is a tool to help in the distribution of large files like CD
       and DVD images; see 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
       xorriso can produce a .jigdo and a .template  file  together  with  a  single-session  ISO
       image.   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 xorriso session on a blank -outdev,
       and a checksum 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 checksum file by a single text line:
       Checksum as hex digits, 2 blanks, size as 12 decimal digits or blanks, 2 blanks,  symbolic
       file address
       The  kind  of  checksum is chosen by -jigdo "checksum_algorithm" with values "md5" (32 hex
       digits) or "sha256" (64 hex digits).  It will also be used for the file address  lines  in
       the .jigdo file.  The default is "md5".
       The file address in a checksum file 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 xorriso will refuse to write to
       non-blank targets, it will disable multi-session emulation, and padding will be counted as
       part of the ISO image.

       -jigdo parameter_name value
              Clear  Jigdo  Template  Extraction  parameter list or add a parameter to that list.
              The alias names are the corresponding genisoimage options.  They  are  accepted  as
              parameter  names  as  well.  Especially  they  are  recognized  by  the -as mkisofs
              emulation command.
              Parameter clear with any value empties the whole list.   No  .jigdo  and  .template
              file will be produced.
              checksum_algorithm  chooses the checksum algorithm which shall be used for the data
              file entries in the .jigdo file and is expected in the checksum  file.  Permissible
              are "md5" or "sha256". Default is "md5".
              Alias: -jigdo-checksum-algorithm
              template_path  sets  the  disk_path  for  the  .template  file  with  the holed and
              compressed ISO image copy.
              Alias: -jigdo-template
              jigdo_path sets the disk_path for the .jigdo file with the checksums  and  download
              addresses for filling the holes in .template.
              Alias: -jigdo-jigdo
              checksum_path sets the disk_path where to find the checksum file with symbolic file
              addresses and checksums according to checksum_algorithm.
              Alias: md5_path
              Alias: -checksum-list
              Alias: -md5-list
              min_size sets the minimum size for a data file to be listed in the .jigdo file  and
              being a hole in the .template file.
              Alias: -jigdo-min-file-size
              exclude adds 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
              Alias: -jigdo-exclude
              demand_checksum  adds a regular expression pattern which will get compared with the
              absolute disk_path of any data file that was not found in the checksum list file as
              of "checksum_path". A match causes a MISHAP event.
              Alias: demand_md5
              Alias: -jigdo-force-checksum
              Alias: -jigdo-force-md5
              mapping  adds  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  checksum 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.
              Alias: -jigdo-map
              compression chooses one of "bzip2" or "gzip" for the compression  of  the  template
              file. The jigdo file is put out uncompressed.
              Alias: -jigdo-template-compress
              checksum_iso  chooses  one  or  more  of  "md5", "sha1", "sha256", "sha512" for the
              auxiliary "# Image Hex" checksums in the jigdo file. The value may e.g.  look  like
              "md5,sha1,sha512".  Value  "all"  chooses  all available algorithms.  Note that MD5
              stays always enabled.
              Alias: -checksum_algorithm_iso
              checksum_template is like checksum_iso but for "# Template Hex".
              Alias: -checksum_algorithm_template

       Character sets:

       File names are strings of non-zero bytes with 8 bit  each.  Unfortunately  the  same  byte
       string  may  appear  as different peculiar national characters on differently nationalized
       terminals.  The meanings of byte codes are defined in character  sets  which  have  names.
       Shell command iconv -l lists them.
       The  file names on hard disk are assumed to be encoded by the local character set which is
       also used for the communication with the  user.   Byte  codes  32  to  126  of  the  local
       character  set  must  match  the  US-ASCII characters of the same code. ISO-8859 and UTF-8
       fulfill this demand.
       By default, xorriso uses the character set as told by shell command "locale" with argument
       "charmap".  This  may be influenced by environment variables LC_ALL, LC_CTYPE, or LANG and
       should match the expectations of the terminal.  In some situations it may be necessary  to
       set it by command -local_charset.
       Local 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 media use the same  local
       character  set.  Outside these constraints it may be necessary to let xorriso convert byte
       codes from and to other character sets.
       The Rock Ridge file names in ISO filesystems are  assumed  to  be  encoded  by  the  input
       character  set.   The Rock Ridge file names which get written with ISO filesystems will be
       encoded by the output character set.
       The sets can be defined independently by commands -in_charset and  -out_charset.  Normally
       one  will  have  both  identical,  if ever.  Other than the local character set, these two
       character sets may deviate from US-ASCII.
       The output character sets for Joliet and HFS+ are not influenced by these commands. Joliet
       uses output character set UCS-2 or UTF-16. HFS+ uses UTF-16.
       The  default output charset is the local character set of the terminal where xorriso runs.
       So by default no conversion happens between local filesystem names and emerging Rock Ridge
       names  in  the  image.  The  situation  stays  ambiguous and the reader has to riddle what
       character set was used.
       By command -auto_charset it is possible to attribute the output charset name to the image.
       This  makes  the  situation unambiguous. But if your terminal character set does not match
       the character set of the local file names, then this attribute can  become  plainly  wrong
       and  cause  problems  at  read time.  To prevent this it is necessary to check whether the
       terminal properly displays all intended filenames. Check especially  the  exotic  national
       To  enforce  recording  of a particular character set name without any conversion at image
       generation time,  set  -charset  and  -local_charset  to  the  desired  name,  and  enable
       -backslash_codes to avoid evil character display on your terminal.

       -charset character_set_name
              Set the character set from which to convert file names when loading an image and to
              which to convert when writing an image.

       -local_charset character_set_name
              Override the system assumption of the local character set name.   If  this  appears
              necessary,  one  should  consider to set -backslash_codes to "on" in order to avoid
              dangerous binary codes being sent to the terminal.

       Exception processing:

       Since the tasks of xorriso are manifold and prone to external influence, there  may  arise
       the need for xorriso to report and handle problem events.
       Those  events  get  classified  when  they are detected by one of the software modules and
       forwarded to reporting and evaluation modules which decide about reactions. Event  classes
       are sorted by severity:
       "NEVER" The upper end of the severity spectrum.
       "ABORT" The program is being aborted and on its way to end.
       "FATAL" The main purpose of the run failed or an important resource failed unexpectedly.
       "FAILURE" An important part of the job could not be performed.
       "MISHAP" A FAILURE which can be tolerated during ISO image generation.
       "SORRY" A less important part of the job could not be performed.
       "WARNING" A situation is suspicious of being not intended by the user.
       "HINT" A proposal to the user how to achieve better results.
       "NOTE" A harmless information about noteworthy circumstances.
       "UPDATE" A pacifier message during long running operations.
       "DEBUG" A message which would only interest the program developers.
       "ALL" The lower end of the severity spectrum.

       -abort_on severity
              Set the severity threshold for events to abort the program.
              Useful: "NEVER", "ABORT", "FATAL", "FAILURE" , "MISHAP", "SORRY"
              It  may  become  necessary to abort the program anyway, despite the setting by this
              command. Expect not many "ABORT" events to be ignorable.
              A special property of this command is that it works preemptive if given as  program
              start  argument.  I.e.  the first -abort_on setting among the start arguments is in
              effect already when the first operations of xorriso begin.  Only  "-abort_on"  with
              dash "-" is recognized that way.

       -return_with severity exit_value
              Set  the  threshold  and  exit_value  to be returned at program end if no abort has
              happened. This is to allow xorriso to go on after problems but  to  get  a  failure
              indicating exit value from the program, nevertheless.  Useful is a value lower than
              the -abort_on threshold, down to "WARNING".
              exit_value may be either 0 (indicating success to the starter of the program) or  a
              number  between 32 and 63. Some other exit_values are used by xorriso if it decides
              to abort the program run:
              1=abort due to external signal
              2=no program arguments given
              3=creation of xorriso main object failed
              4=failure to start libraries
              5=program abort during argument processing
              6=program abort during dialog processing

       -report_about severity
              Set the threshold for events to be reported.
              Useful:  "SORRY", "WARNING", "HINT", "NOTE", "UPDATE", "DEBUG", "ALL"
              Regardless what is set by -report_about, messages get always reported if they reach
              the severity threshold of -abort_on .
              Event  messages are sent to the info channel "I" which is usually stderr but may be
              influenced by command -pkt_output.  Info messages which  belong  to  no  event  get
              attributed severity "NOTE".
              A  special  property  of this command is that the first -report_about setting among
              the start arguments is in effect already  when  the  first  operations  of  xorriso
              begin. Only "-report_about" with dash "-" is recognized that way.

       -signal_handling mode
              Control  the installation of a signal handler which shall react on external signals
              (e.g. from program "kill" or from keys Ctrl+C)  or  on  signals  caused  by  severe
              program errors.
              Mode "on" is the default. It uses the signal handler of libburn which produces ugly
              messages but puts much effort in releasing optical drives before xorriso ends.
              Mode "off" as first -signal_handling among the start  arguments  prevents  all  own
              signal precautions of xorriso. Inherited signal handler settings stay as they are.
              It  works  like  "sig_dfl"  if  given  after  other  signal  handling  was  already
              established at program start.
              Mode "sig_dfl" uses the system provided  default  handling  of  signals,  which  is
              normally  a  sudden  abort  of  the  program.  To prevent stuck drives, the libburn
              handler is used during burning, blanking, and formatting on MMC drives.
              Mode "sig_ign" tries to ignore as many signal types as possible. This  imposes  the
              risk  that  xorriso  refuses to end until externally kill -9 if performed.  kill -9
              then imposes the risk that the drive is left in unusable state and  needs  poweroff
              to  be  reset.  So during burning, blanking, and formatting wait for at least their
              normal run time before killing externally.
              A special property of this command is that the first -signal_handling setting among
              the  start  arguments  is  in  effect  already when the first operations of xorriso
              begin. Only "-signal_handling" with dash "-" is recognized that way.

       -error_behavior occasion behavior
              Control the program behavior at problem event occasions.  For now this  applies  to
              occasions "image_loading" which is given while an image tree is read from the input
              device, and  to  "file_extraction"  which  is  given  with  osirrox  commands  like
              With "image_loading" there are three behaviors available:
              "best_effort"  goes on with reading after events with severity below FAILURE if the
              threshold of command -abort_on allows this.
              "failure" aborts image tree reading on first event of at least SORRY.  It issues an
              own FAILURE event.  This is the default.
              "fatal" acts like "failure" but issues the own event as FATAL.
              With occasion "file_extraction" there are three behaviors:
              "keep" maintains incompletely extracted files on disk. This is the default.
              "delete" removes files which encountered errors during content extraction.
              "best_effort"  starts  a  revovery  attempt  by  means  of -extract_cut if the file
              content stems from the loaded ISO image and is not filtered.

       Dialog mode control:

       -dialog "on"|"off"|"single_line"
              Enable or disable to enter dialog mode after all program arguments  are  processed.
              In dialog mode input lines get prompted via readline or from stdin.
              If  no  -abort_on severity was set when dialog starts, then "NEVER" is set to avoid
              abort in most cases of wrong input or other problems.  Before  dialog  begins,  the
              default is "FAILURE" which e.g. aborts on unknown commands.
              Mode  "on"  supports  input  of  newline characters within quotation marks and line
              continuation by trailing backslash outside  quotation  marks.   Mode  "single_line"
              does not.

       -page length width
              Describe terminal to the text pager. See also above, paragraph Result pager.
              If  parameter  length  is  nonzero then the user gets prompted after that number of
              terminal lines. Zero length disables paging.
              Parameter width is the number of characters  per  terminal  line.  It  is  used  to
              compute the number of terminal lines which get occupied by an output line.  A usual
              terminal width is 80.

       -use_readline "on"|"off"
              If "on" then use readline for dialog. Else use plain stdin.
              See also above, paragraph Dialog, Readline, Result pager.

       -reassure "on"|"tree"|"off"
              If "on" then ask the user for "y" or "n":
              before deleting or overwriting any file in the ISO image,
              before overwriting any disk file during restore operations,
              before rolling back pending image changes,
              before committing image changes to media,
              before changing the input drive,
              before blanking or formatting media,
              before ending the program.
              With setting "tree" the reassuring prompt will appear  for  an  eventual  directory
              only once and not for each file in its whole subtree.
              Setting  "off"  silently  kills  any  kind  of image file object and performs above
              irrevocable actions.
              To really produce user prompts, command -dialog needs to be set to "on".  Note that
              the prompt does not appear in situations where file removal is forbidden by command
              -overwrite. -reassure only imposes an additional curb for  removing  existing  file
              Be  aware  that  file  objects  get  deleted  from  the ISO image immediately after
              confirmation. They are gone even if  the  running  command  gets  aborted  and  its
              desired  effect  gets revoked. In case of severe mess-up, consider to use -rollback
              to revoke the whole session.

       Drive and media related inquiry actions:

              Show list of available MMC drives with the  addresses  of  their  libburn  standard
              device files.
              This  is  only  possible when no ISO image changes are pending.  After this command
              was executed, there is no drive current and no image loaded.
              In order to be visible, a device has  to  offer  rw-permissions  with  its  libburn
              standard  device  file.  Thus it might be only the superuser who is able to see all
              Drives which are occupied by other processes get not shown.

              Like -devices, but presenting the drives with addresses  of  symbolic  links  which
              point to the actual device files.
              Modern  GNU/Linux  systems may shuffle drive addresses from boot to boot.  The udev
              daemon is supposed to create links which always point to the same drive, regardless
              of its system address.  The command -device_links shows the addresses of such links
              if they begin by "/dev/dvd" or "/dev/cd".  Precedence is: "dvdrw",  "cdrw",  "dvd",
              "cdrom", "cd".

              Show  media  specific tables of content. This is the session history of the medium,
              not the ISO image directory tree.
              In case of overwriteable media holding a valid ISO image, it may happen that only a
              single  session gets shown. But if the first session on the overwriteable media was
              written by xorriso then a complete session history can be emulated.
              A drive which is incapable of writing may show any media as CD-ROM or DVD-ROM  with
              only  one  or  two sessions on it. The last of these sessions is supposed to be the
              most recent real session then.
              Some read-only drives and media show no usable session  history  at  all.   Command
              -rom_toc_scan might help.
              If  input  device  and  output device are both acquired and not the same, then both
              tables-of-content get shown.

       -toc_of "in"|"out"|"all"[":short"]
              Like command -toc but explicitly choosing which drive's table-of-content  to  show.
              "in"  shows  -indev  or  -dev, "out" shows -outdev or -dev, "all" shows the same as
              If ":short" is appended to the drive choosing word, then only a  short  summary  of
              drive state and medium content is printed.
              As  further  difference  to  -toc, this command does not emit FAILURE events if the
              desired drive is not acquired.

       -mount_cmd drive entity id path
              Emit an appropriate command line for mounting the ISO session indicated  by  drive,
              entity and id.  The result will be different on GNU/Linux and on FreeBSD or NetBSD.
              drive  can be "indev" or "outdev" to indicate already acquired drives, or it can be
              the path of a not yet acquired drive.  Prefix "stdio:" for non-MMC  drives  is  not
              For  entity and id, see also command -load. They must be either "sbsector" with the
              superblock sector address as id, or "track" with a track number as id, or "session"
              with  a  session  number,  or  "volid"  with a search pattern for the volume id, or
              "auto" with which any text as id mounts the first track of the last session.
              path will be used as mount point and must already exist as a directory on disk.
              The command gets printed to the result  channel.  See  command  -mount  for  direct
              execution of this command.

       -mount_opts option[:option...]
              Set  options  which influence -mount and -mount_cmd. Currently there is only option
              "exclusive" which is default  and  its  counterpart  "shared".  The  latter  causes
              xorriso  not  to  give  up the affected drive with command -mount.  On GNU/Linux it
              adds mount option "loop" which may enable mounting of several sessions of the  same
              block device at the same time. One should not write to a mounted optical medium, of
              course. Take care to umount all sessions before ejecting.

       -session_string drive entity id format
              Print to the result channel a text which gets composed according to format and  the
              parameters of the addressed session.
              Formats  "linux:"path  or  "freebsd:"path  produce the output of -mount_cmd for the
              given operating systems.
              In other texts xorriso will substitute the following parameter names.  An  optional
              prefix "string:" will be removed.
              "%device%" will be substituted by the mountable device path of the drive address.
              "%sbsector%" will be substituted by the session start sector.
              "%track%",  "%session%",  "%volid%"  will  be  substituted by track number, session
              number, or volume id of the depicted session.

              Print the foreseeable consumption of 2048 byte blocks by  next  -commit.  This  can
              last  a while as a -commit gets prepared and only in last moment is revoked by this
              command.  The result depends on several settings and also on  the  kind  of  output
              device.   If no -jidgo options are set and not command -as "mkisofs" was used, then
              -padding (300 kB by default) is not counted as part of the image size.
              If an El Torito boot image file  is  already  depicted,  then  command  -print_size
              automatically executes -boot_image "any" "next".  This means that the properties of
              that boot image cannot be edited by subsequent commands.

              Print available space on the output medium and the  free  space  after  subtracting
              already foreseeable consumption by next -commit.
              Note that the title of the prediction "After commit :" is misleading.  It is rather
              the space that may still be filled in this session without making the next  -commit
              fail from medium overflow.
              The free space after the next -commit might be smaller by several MB.  This depends
              on medium type, number of recorded sessions, and drive habits.

              Print various ID strings and timestamps which can be found in  loaded  ISO  images.
              Some  of  the  IDs may be changed by commands like -volid or -publisher.  For these
              IDs -pvd_info reports what would be written with the next -commit.  The  timestamps
              get not automatically propagated from loaded image to newly written image. The ones
              for new images may be set by command -volume_date.  See there for  the  meaning  of
              the particular timestamps.

       -report_el_torito mode
              With  mode  plain  print a report about the information found in the El Torito boot
              catalog of the loaded ISO image.
              With mode help print a text which explains the meaning of  the  lines  put  out  by
              Mode  cmd  tries  to  print the xorriso commands which are necessary to produce the
              found boot equipment: disk identifiers, El Torito boot  images,  and  System  Area.
              Disk  identifiers  are strings which the booting operating system might use to find
              the ISO filesystem from where it comes. Currently known is the use of volume id and
              modification date.
              The  intended  use  case  is  modification  of  the filesystem by having -indev and
              -outdev pointing to different images or drives.  The result might be  insufficient,
              if  the  found  equipment  cannot  be produced by xorriso. Various SORRY events may
              arise in this case, but it is  not  guaranteed  that  xorriso  recognizes  all  its
              Mode as_mkisofs tries to print the xorriso -as mkisofs options, which are necessary
              to produce the found equipment.  The intended  use  case  is  to  use  the  mounted
              filesystem as input tree together with the printed options.

       -report_system_area mode
              With  mode  plain  print a report about the information found in the System Area of
              the loaded ISO image. The report consists of zero to many lines with a header text,
              a colon, and information text.
              With  mode  help  print  a  text which explains the meaning of the lines put out by
              "plain". You probably will have to look for more documentation which  explains  the
              technical details of the mentioned boot facilities.
              Modes cmd and as_mkisofs work like with command -report_el_torito. See above.
              With  mode gpt_disk_guid print the GPT disk GUID of the loaded ISO in RFC 4122 text
              format to result channel. It is not considered an error if no GPT  is  present.  In
              this case nothing is printed to result channel.
              With  mode  gpt_crc_of:disk_path read up to 32 KiB from the disk file with the path
              given after the colon. Compute the GPT compliant CRC number and  print  it  to  the
              result  channel.  The number is shown like "0x690fd979".  The special disk_path "-"
              causes reading from standard input.
              With mode make_guid print a pseudo-random GUID in RFC 4122 text  format  to  result

       Navigation in ISO image and disk filesystem:

       -cd iso_rr_path
              Change  the  current  working  directory  in  the  ISO image.  This is prepended to
              iso_rr_paths which do not begin with '/'.
              It is possible to set the working directory to a path which does not exist  yet  in
              the ISO image. The necessary parent directories will be created when the first file
              object is inserted into that virtual directory.  Use -mkdir if you want to  enforce
              the existence of the directory already at first insertion.

       -cdx disk_path
              Change  the  current working directory in the local filesystem.  To be prepended to
              disk_paths which do not begin with '/'.

              Tell the current working directory in the ISO image.

              Tell the current working directory in the local filesystem.

       -ls iso_rr_pattern [***]
              List files in the ISO image which match shell patterns (i.e. with wildcards '*' '?'
              '[a-z]').   If a pattern does not begin with '/' then it is compared with addresses
              relative to -cd.
              Directories are listed by their content rather than as single file item.
              Pattern expansion may be disabled by command -iso_rr_pattern.

       -lsd iso_rr_pattern [***]
              Like -ls but listing directories as themselves and  not  by  their  content.   This
              resembles shell command ls -d.

       -lsl iso_rr_pattern [***]
              Like  -ls  but  also list some of the file attributes.  The output format resembles
              shell command ls -ln.
              File type 'e' indicates the El Torito boot catalog.
              If the file has non-trivial ACL, then a '+' is appended to the permission info.  If
              the file is hidden, then 'I' for "iso_rr", 'J' for "joliet", 'A' for "hfsplus", 'H'
              for multiple hiding gets appended.  Together with ACL it is 'i', 'j', 'a', 'h'.

       -lsdl iso_rr_pattern [***]
              Like -lsd but also list some of the file attributes.  The output  format  resembles
              shell command ls -dln.

       -lsx disk_pattern [***]
              List  files  in  the local filesystem which match shell patterns. Patterns which do
              not begin with '/' are used relative to -cdx.
              Directories are listed by their content rather than as single file item.
              Pattern expansion may be disabled by command -disk_pattern.

       -lsdx disk_pattern [***]
              Like -lsx but listing directories as themselves and not  by  their  content.   This
              resembles shell command ls -d.

       -lslx disk_pattern [***]
              Like  -lsx  but  also listing some of the file attributes.  Output format resembles
              shell command ls -ln.

       -lsdlx disk_pattern [***]
              Like -lsdx but also listing some of the file attributes.  Output  format  resembles
              shell command ls -dln.

       -getfacl iso_rr_pattern [***]
              Print  the  access permissions of the given files in the ISO image using the format
              of shell command getfacl. If a file has no ACL then it  gets  fabricated  from  the
              -chmod settings. A file may have a real ACL if it was introduced into the ISO image
              while command -acl was set to "on".

       -getfacl_r iso_rr_pattern [***]
              Like -gefacl but listing recursively  the  whole  file  trees  underneath  eventual

       -getfattr iso_rr_pattern [***]
              Print  the  xattr of the given files in the ISO image.  If a file has no such xattr
              then noting is printed for it.  The choice of namespaces depends on the setting  of
              command  -xattr:  "on" or "user" restricts it to namespace "user", "any" only omits
              namespace "isofs".

       -getfattr_r iso_rr_pattern [***]
              Like  -gefattr  but  listing  recursively  the  whole  file  trees  underneath   of

       -du iso_rr_pattern [***]
              Recursively  list size of directories and files in the ISO image which match one of
              the patterns.  similar to shell command du -k.

       -dus iso_rr_pattern [***]
              List size of directories and files  in  the  ISO  image  which  match  one  of  the
              patterns.  Similar to shell command du -sk.

       -dux disk_pattern [***]
              Recursively  list size of directories and files in the local filesystem which match
              one of the patterns. Similar to shell command du -k.

       -dusx disk_pattern [***]
              List size of directories and files in the local filesystem which match one  of  the
              patterns.  Similar to shell command du -sk.

       -findx disk_path [-name pattern] [-type t] [-exec action [params]] --
              Like  -find  but  operating  on local filesystem and not on the ISO image.  This is
              subject to the settings of -follow.
              -findx accepts the same -type parameters as -find. Additionally it recognizes  type
              "mountpoint"  (or  "m")  which  matches  subdirectories which reside on a different
              device than their parent. It never matches the disk_path given as start address for
              -findx  accepts  the  -exec  actions  as  does  -find. But except the following few
              actions it will always perform action "echo".
              in_iso reports the path if its counterpart exists in the ISO image.  For  this  the
              disk_path  of  the  -findx  command  gets  replaced  by  the  iso_rr_path  given as
              E.g.: -findx /home/thomas -exec in_iso /thomas_on_cd --
              not_in_iso reports the path if its counterpart does not exist in the ISO image. The
              report format is the same as with command -compare.
              add_missing  iso_rr_path_start adds the counterpart if it does not yet exist in the
              ISO image and marks it for "rm_merge" as non-removable.
              E.g.: -findx /home/thomas -exec add_missing /thomas_on_cd --
              is_full_in_iso reports if the counterpart in the ISO image contains  files.  To  be
              used with -type "m" to report mount points.
              empty_iso_dir  deletes  all files from the counterpart in the ISO image. To be used
              with -type "m" to truncate mount points.
              estimate_size prints a lower and an upper estimation of the number of blocks  which
              the  found  files  together  will  occupy in the emerging ISO image.  This does not
              account for the superblock, for the directories in the -findx path,  or  for  image
              list_extattr  mode  prints  a script to the result channel, which would use FreeBSD
              command setextattr to set the file's xattr name-value pairs of user namespace.  See
              -find for a description of parameter mode.
              E.g. -exec list_extattr e --

       -compare disk_path iso_rr_path
              Compare  attributes  and  eventual  data  file content of a fileobject in the local
              filesystem with a file object in the ISO image. The iso_rr_path may well  point  to
              an  image  file  object  which is not yet committed, i.e. of which the data content
              still resides in the local filesystem. Such data content  is  prone  to  externally
              caused changes.
              If iso_rr_path is empty then disk_path is used as path in the ISO image too.
              Differing attributes are reported in detail, differing content is summarized.  Both
              to the result channel. In case of no differences no result lines are emitted.

       -compare_r disk_path iso_rr_path
              Like -compare but working recursively. I.e. all file objects below  both  addresses
              get  compared  whether  they  have counterparts below the other address and whether
              both counterparts match.

       -compare_l disk_prefix iso_rr_prefix disk_path [***]
              Perform -compare_r with each of  the  disk_path  parameters.  iso_rr_path  will  be
              composed from disk_path by replacing disk_prefix by iso_rr_prefix.

       -show_stream iso_rr_path [***]
              Display the content stream chain of data files in the ISO image. The chain consists
              of the iso_rr_name and one or more streams, separated by " <  "  marks.   A  stream
              description  consists of one or more texts, separated by ":" characters.  The first
              text tells the stream type, the following ones, if ever,  describe  its  individual
              properties.  Frequently used types are:
               disk:'disk_path'  for local filesystem objects.
               image:'iso_rr_path'  for ISO image file objects.
               cout:'disk_path offset count'  for -cut_out files.
               extf:'filter_name' for external filters.
               '/abc/xyz.gz' < extf:'gzip' < disk:'/home/me/x'

       -show_stream_r iso_rr_path [***]
              Like -show_stream but working recursively.

       Evaluation of readability and recovery:

       It  is not uncommon that optical media produce read errors. The reasons may be various and
       get obscured by error correction which is performed by the drives and based on extra  data
       on the media. If a drive returns data then one can quite trust that they are valid. But at
       some degree of read problems the correction  will  fail  and  the  drive  is  supposed  to
       indicate error.
       xorriso  can scan a medium for readable data blocks, classify them according to their read
       speed, save them to a file, and keep track of successfully saved blocks for further  tries
       on the same medium.
       By  command  -md5  checksums  may  get  recorded with data files and whole sessions. These
       checksums are reachable only via indev and a loaded image.  They work independently of the
       media type and can detect transmission errors.

       -check_media [option [option ...]] --
              Try  to read data blocks from the indev drive, optionally copy them to a disk file,
              and finally report about the encountered quality. Several options may  be  used  to
              modify the default behavior.
              The parameters given with this command override the default settings which may have
              been changed by command -check_media_defaults.  See  there  for  a  description  of
              available options.
              The  result  list  tells  intervals  of  2 KiB blocks with start address, number of
              blocks and quality. Qualities which  begin  with  "+"  are  supposed  to  be  valid
              readable  data. Qualities with "-" are unreadable or corrupted data.  "0" indicates
              qualities which are not covered by the check run or are  regularly  allowed  to  be
              unreadable (e.g. gaps between tracks).
              Alternatively it is possible to report damaged files rather than blocks.
              If  -md5  is "on" then the default mode what=tracks looks out for libisofs checksum
              tags for the ISO session data and checks them against the checksums  computed  from
              the data stream.

       -check_media_defaults [option [option ...]] --
              Preset  options  for  runs  of  -check_media,  -extract_cut  and  best_effort  file
              extraction. Options given with  -check_media  will  override  the  preset  options.
              -extract_cut will override some options automatically.
              An option consists of a keyword, a "=" character, and a value. Options may override
              each other. So their sequence matters.
              The default setting at program start is:
              use=indev what=tracks min_lba=-1 max_lba=-1 retry=default
              time_limit=28800 item_limit=100000 data_to='' event=ALL
              sector_map='' map_with_volid=off patch_lba0=off report=blocks
              bad_limit=invalid slow_limit=1.0 chunk_size=0s async_chunks=0
              Option "reset=now" restores these startup defaults.
              Non-default options are:
              report="files" lists the files which use damaged blocks (not with use=outdev).  The
              format  is  like  with  find -exec report_damage.  Note that a MD5 session mismatch
              marks all files of the session  as  damaged.   If  finer  distinction  is  desired,
              perform -md5 off before -check_media.
              report="blocks_files" first lists damaged blocks and then affected files.
              use="outdev"  reads  from  the output drive instead of the input drive. This avoids
              loading the ISO image tree from media.
              use="sector_map" does not read any  media  but  loads  the  file  given  by  option
              sector_map= and processes this virtual outcome.
              what="disc" scans the payload range of a medium without respecting track gaps.
              what="image" similar to "disc", but restricts scanning to the range of the ISO 9660
              image, if present.
              min_lba=limit omits all blocks with addresses lower than limit.
              max_lba=limit switches to what=disc and omits all blocks above limit.
              chunk_size=size sets the  number  of  bytes  to  be  read  in  one  low-level  read
              operation.   This gets rounded down to full blocks of 2048 bytes. 0 means automatic
              retry="on" forces read retries with minimal senseful chunk  size  when  the  normal
              read chunk produces a read error. This size is 1s with CD and stdio files, 16s with
              DVD (1 ECC Block), and 32s with BD (1  Cluster).   By  default,  retries  are  only
              enabled with CD media. "retry=off" forbits retries for all media types.
              abort_file=disk_path  gives  the path of the file which may abort a scan run. Abort
              happens if the file exists and its mtime is not older than the start  time  of  the
              run. Use shell command "touch" to trigger this.  Other than an aborted program run,
              this will report the tested and untested blocks and go on with running xorriso.
              time_limit=seconds gives the number of  seconds  after  which  the  scan  shall  be
              aborted.  This  is  useful for unattended scanning of media which may else overwork
              the drive in its effort to squeeze out some readable blocks.  Abort may be  delayed
              by  the  drive gnawing on the last single read operation.  Value -1 means unlimited
              item_limit=number gives the number of report  list  items  after  which  to  abort.
              Value -1 means unlimited item number.
              data_to=disk_path copies the valid blocks to the given file.
              event=severity sets the given severity for a problem event which shall be issued at
              the end of a check run if data blocks were unreadable or failed to  match  recorded
              MD5 checksums. Severity "ALL" disables this event.
              sector_map=disk_path tries to read the file given by disk_path as sector bitmap and
              to store such a map file after the scan run.  The bitmap tells  which  blocks  have
              been  read  successfully in previous runs.  It is the persistent memory for several
              scans on the same medium,  even  with  intermediate  eject,  in  order  to  collect
              readable blocks whenever the drive is lucky enough to produce them. The stored file
              contains a human readable TOC of tracks and their start block  addresses,  followed
              by binary bitmap data.
              By  default,  untested  blocks  are not considered bad, but rather as intentionally
              unread. If you expect time_limit= or item_limit= to abort the run, then consider to
              use bad_limit="untested".
              map_with_volid="on"  examines  tracks  whether they are ISO images and prints their
              volume IDs into the human readable TOC of sector_map=.
              patch_lba0="on" transfers within the data_to= file a copy of the  currently  loaded
              session head to the start of that file and patches it to be valid at that position.
              This makes the loaded session the last valid session of the image file when it gets
              mounted  or  loaded  as stdio: drive. New sessions will be appended after this last
              session and will overwrite any sessions which have followed it.
              patch_lba0="force" performs patch_lba0="on"  even  if  xorriso  believes  that  the
              copied data are not valid.
              patch_lba0=  may  also  bear  a  number. If it is 32 or higher it is taken as start
              address of the session to be copied. In this case it is not necessary  to  have  an
              -indev and a loaded image. ":force" may be appended after the number.
              bad_limit=threshold  sets  the highest quality which shall be considered as damage.
              Choose  one  of  "good",  "md5_match",  "slow",  "partial",  "valid",   "untested",
              "md5_mismatch", "invalid", "tao_end", "off_track", "unreadable".
              "valid" and "invalid" are qualities imported from a sector_map file.  "tao_end" and
              "off_track" are intentionally not readable, but  not  bad  either.   "partial"  are
              blocks  retrieved  from  a partially readable chunk. They are supposed to be ok but
              stem from a suspicious neighborhood.
              "md5_match" and "md5_mismatch" regions overlap with regions of other quality.   The
              former is a strong confirmation for quality, the latter only tells that one or more
              blocks of the region must be wrong.
              By default bad_limit is set  higher  than  md5_mismatch,  so  that  mismatches  are
              classified  as  quality class "0" rather than "-". This means that the sectors of a
              MD5 mismatch range are recorded in the sector_map  as  successfully  read,  if  the
              drive  handed  them  out at all. Set "bad_limit=md5_mismatch" to let the sector_map
              record the whole mismatching range as yet not retrieved.
              slow_limit=threshold sets the  time  threshold  for  a  single  read  chunk  to  be
              considered slow. This may be a fractional number like 0.1 or 1.5.
              async_chunks=number  enables  asynchronous MD5 processing if number is 2 or larger.
              In this case the given number of read chunks is allocated as fifo buffer.  On  very
              fast MMC drives try: chunk_size=64s async_chunks=16.

       -check_md5 severity iso_rr_path [***]
              Compare the data content of the given files in the loaded image with their recorded
              MD5 checksums, if there are any. In case of any mismatch  an  event  of  the  given
              severity  is  issued.  It  may  then be handled by appropriate settings of commands
              -abort_on or -return_with which both can cause non-zero exit values of the  program
              run. Severity ALL suppresses that event.
              This  command  reports  match  and  mismatch  of  data files to the result channel.
              Non-data files cause NOTE events. There  will  also  be  UPDATE  events  from  data
              If  no  iso_rr_path is given then the whole loaded session is compared with its MD5
              sum. Be aware that this covers only one session and not the whole  image  if  there
              are older sessions.

       -check_md5_r severity iso_rr_path [***]
              Like  -check_md5  but  checking  all  data  files underneath the given paths.  Only
              mismatching data files will be reported.

       osirrox ISO-to-disk restore commands:

       Normally xorriso only writes to disk files which were given as stdio: pseudo-drives or  as
       log  files.  But its alter ego osirrox is able to extract file objects from ISO images and
       to create, overwrite, or delete file objects on disk.
       Disk file exclusions by -not_mgt, -not_leaf,  -not_paths  apply.   If  disk  file  objects
       already  exist  then  the  settings of -overwrite and -reassure apply. But -overwrite "on"
       only triggers the behavior of -overwrite "nondir". I.e. directories cannot be deleted.
       Access permissions of files in the ISO image do not  restrict  restoring.   The  directory
       permissions on disk have to allow rwx.

       -osirrox setting[:option:...]
              Setting  "off"  disables  disk filesystem manipulations. This is the default unless
              the program was started with leafname "osirrox". Elsewise the capability to restore
              files  can  be enabled explicitly by -osirrox "on".  It can be irrevocably disabled
              by -osirrox "banned".
              The setting "blocked" is like  "off".  But  it  can  only  be  revoked  by  setting
              "unblock",  which  elsewise  is like "on". This can be used to curb command scripts
              which might use "on" undesiredly.
              To enable restoring of special files by "device_files"  is  potentially  dangerous.
              The  meaning  of  the number st_rdev (see man 2 stat) depends much on the operating
              system. Best is to restore device files only to the same  system  from  where  they
              were  copied.  If  not  enabled,  device  files in the ISO image are ignored during
              restore operations.
              Due to a bug of previous versions, device files from previous sessions  might  have
              been altered to major=0, minor=1. So this combination does not get restored.
              Option "concat_split_on" is default. It enables restoring of split file directories
              as data files if the directory contains a  complete  collection  of  -cut_out  part
              files.  With  option "concat_split_off" such directories are handled like any other
              ISO image directory.
              Option  "auto_chmod_off"  is  default.  If  "auto_chmod_on"  is  set  then   access
              restrictions  for  disk directories get circumvented if those directories are owned
              by the effective user who runs xorriso. This happens by  temporarily  granting  rwx
              permission to the owner.
              Option  "sort_lba_on"  may  improve  read  performance  with optical drives. It can
              restore large numbers of hard links without exhausting -temp_mem_limit. It does not
              preserve  directory  mtime  and  it needs -osirrox option auto_chmod_on in order to
              extract directories which offer no write permission. Default is "sort_lba_off".
              Option "o_excl_on" is the default unless the  program  was  started  with  leafname
              "osirrox".  On GNU/Linux it tries to avoid using drives which are mounted or in use
              by other libburn programs.  Option "o_excl_off" on GNU/Linux enables access to such
              drives  by the equivalent of -drive_access "shared:readonly". I.e. drives which get
              acquired while "o_excl_off" will refuse to  get  blanked,  formatted,  written,  or
              ejected.  But  be  aware  that  even  harmless inquiries can spoil ongoing burns of
              CD-R[W] and DVD-R[W].
              Option "strict_acl_off" is  default.  It  tolerates  on  FreeBSD  the  presence  of
              directory  "default"  ACLs  in  the ISO image. With "strict_acl_on" these GNU/Linux
              ACLs cause on FreeBSD a FAILURE event during restore with -acl "on".

       -extract iso_rr_path disk_path
              Copy the  file  objects  at  and  underneath  iso_rr_path  to  their  corresponding
              addresses at and underneath disk_path.  This is the inverse of -map or -update_r.
              If  iso_rr_path  is  a  directory  and disk_path is an existing directory then both
              trees will be merged. Directory attributes get extracted only if the disk directory
              is newly created by the copy operation.  Disk files get removed only if they are to
              be replaced by file objects from the ISO image.
              As many attributes as possible are copied together with restored file objects.

       -extract_single iso_rr_path disk_path
              Like -extract, but if iso_rr_path is  a  directory  then  its  sub  tree  gets  not

       -extract_l iso_rr_prefix disk_prefix iso_rr_path [***]
              Perform  -extract  with  each  of  the  iso_rr_path  parameters.  disk_path will be
              composed from iso_rr_path by replacing iso_rr_prefix by disk_prefix.

       -extract_cut iso_rr_path byte_offset byte_count disk_path
              Copy a byte interval from a data file out of an ISO image into a newly created disk
              file.   The main purpose for this is to offer a way of handling large files if they
              are not supported by mount -t iso9660 or if the target disk filesystem cannot store
              large files.
              If  the data bytes of iso_rr_path are stored in the loaded ISO image, and no filter
              is applied, and  byte_offset  is  a  multiple  of  2048,  then  a  special  run  of
              -check_media  is  performed.  It  may  be  quicker and more rugged than the general
              reading method.

       -cpx iso_rr_path [***] disk_path
              Copy single leaf file objects from the ISO image to the address given by disk_path.
              If  more  then  one  iso_rr_path  is  given  then  disk_path must be a directory or
              non-existent. In the latter case it  gets  created  and  the  extracted  files  get
              installed in it with the same leafnames.
              Missing directory components in disk_path will get created, if possible.
              Directories  are  allowed  as  iso_rr_path only with -osirrox "concat_split_on" and
              only if they actually represent a complete collection of -cut_out split file parts.

       -cpax iso_rr_path [***] disk_path
              Like -cpx but restoring mtime, atime as in ISO image and trying  to  set  ownership
              and group as in ISO image.

       -cp_rx iso_rr_path [***] disk_path
              Like -cpx but also extracting whole directory trees from the ISO image.
              The  resulting disk paths are determined as with shell command cp -r : If disk_path
              is an existing directory then the trees will be inserted or merged underneath  this
              directory  and  will  keep their leaf names. The ISO directory "/" has no leaf name
              and thus gets mapped directly to disk_path.

       -cp_rax iso_rr_path [***] disk_path
              Like -cp_rx but restoring mtime, atime as in ISO image and trying to set  ownership
              and group as in ISO image.

       -paste_in iso_rr_path disk_path byte_offset byte_count
              Read the content of a ISO data file and write it into a data file on disk beginning
              at the byte_offset. Write at most byte_count bytes.  This is the inverse of command

       -concat mode [target | lim prog [args [...]] lim] iso_rr_path [***]
              Copy  the  data content of one or more data files of the ISO image into a disk file
              object, into a file descriptor, or start a program  and  copy  the  data  into  its
              standard  input.   The  latter is subject to the security restrictions for external
              Modes overwrite and append write into the target  which  is  given  by  the  second
              parameter.  This may be the path to a disk file object, or "-" which means standard
              output, or a text of  the  form  /dev/fd/number,  where  number  is  an  open  file
              descriptor  (e.g.  standard  error  is  /dev/fd/2).  An existing target file is not
              removed before writing begins. If it is not able to take content  data,  then  this
              command  fails.   Mode  overwrite  truncates  regular  data  files to 0 size before
              writing into them.  Example:
               -concat append /home/me/accumulated_text /my/iso/text --

              Mode pipe expects as second parameter a delimiter word which shall mark the end  of
              the  program  argument list. The third argument is the disk_path to the program. It
              must contain at least one '/'. $PATH is not applied.  Further parameters up to  the
              announced delimiter word are used as arguments with the program start. Example:
               -iso_rr_pattern on \
               -concat pipe + /usr/bin/wc + "/my/iso/files*" --

              The  further  parameters  in  all  modes are the iso_rr_paths of data files.  Their
              content gets concatenated in the copy.

       -mount drive entity id path
              Produce the same line as -mount_cmd and then execute it  as  external  program  run
              after giving up the depicted drive. See also -mount_opts.  This demands -osirrox to
              be enabled and normally will succeed only for the superuser. For safety reasons the
              mount program is only executed if it is reachable as /bin/mount or /sbin/mount.

       Command compatibility emulations:

       Writing  of  ISO  9660  on  CD  is traditionally done by program mkisofs as ISO 9660 image
       producer and cdrecord as burn program.  xorriso does not strive  for  their  comprehensive
       emulation.   Nevertheless  it  is ready to perform some of its core tasks under control of
       commands which in said programs trigger comparable actions.

       -as personality option [options] --
              Perform the variable length option list as sparse emulation of the program depicted
              by the personality word.

              Personality "mkisofs" accepts the options listed with:
                -as mkisofs -help --
              Among  them: -R (always on), -r, -J, -o, -M, -C, -dir-mode, -file-mode, -path-list,
              -m, -exclude-list, -f, -print-size, -pad, -no-pad, -V, -v, -version, -graft-points,
              -z,  -no-emul-boot,  -b, -c, -boot-info-table, -boot-load-size, -input-charset, -G,
              -output-charset, -U, -hide, -hide-joliet, -hide-list, -hide-joliet-list, file paths
              and  pathspecs.   A  lot  of  options  are not supported and lead to failure of the
              mkisofs emulation. Some are ignored, but better do not rely on this tolerance.
              The supported options are  documented  in  detail  in  and  in  man
              xorrisofs.  The  description  here is focused on the effect of mkisofs emulation in
              the context of a xorriso run.
              Other than with the "cdrecord" personality there is no automatic -commit at the end
              of  a  "mkisofs"  option  list.  Verbosity  settings  -v (= "UPDATE") and -quiet (=
              "SORRY") persist. The output  file  persists  until  things  happen  like  -commit,
              -rollback, -dev, or end of xorriso.
              Options  which affect all file objects in the ISO image, like -r or -dir-mode, will
              be applied only to files which are present in the ISO image when  the  command  -as
              ends. If you use several -as mkisofs commands in the same run, then consider to put
              such options into the last -as command.
              If files are added  to  the  image,  then  -pacifier  gets  set  to  "mkisofs"  and
              -stdio_sync is defaulted to "off" if no such setting was made yet.
              -graft-points  is  equivalent to -pathspecs on. Note that pathspecs without "=" are
              interpreted differently than with xorriso command  -add.   Directories  get  merged
              with the root directory of the ISO image, other filetypes get mapped into that root
              If pathspecs are given and if no output  file  was  chosen  before  or  during  the
              "mkisofs" option list, then standard output (-outdev "-") will get into effect.  If
              -o points to a regular file, then it will be truncated  to  0  bytes  when  finally
              writing  begins.  This truncation does not happen if the drive is chosen by xorriso
              commands before -as mkisofs or after its list delimiter. Directories  and  symbolic
              links are no valid -o targets.
              Writing  to  stdout is possible only if -as "mkisofs" was among the start arguments
              or if other start arguments pointed the output drive to standard output.
              -print-size inhibits automatic image production at program end. This ban is  lifted
              only if the pending image changes get discarded.
              Padding is counted as part of the ISO image if not option --emul-toc is given.
              If  no -iso-level is given, then level 1 is chosen when the first file or directory
              is added to the image. At the same occasion directory names get allowed to  violate
              the standard by -compliance option allow_dir_id_ext.  This may be avoided by option
              Option -root is supported. Option -old-root  is  implemented  by  xorriso  commands
              -mkdir, -cp_clone, -find update_merge, and -find rm_merge.  -root and -old-root set
              command -disk_dev_ino to "ino_only" and -md5 to "on",  by  default.   -disk_dev_ino
              can be set to "off" by --old-root-no-ino or to "on" by --old-root-devno .  -md5 can
              be set to "off" by --old-root-no-md5 .
              Not original mkisofs options are --quoted_path_list , --hardlinks , --acl , --xattr
              ,  --md5  ,  --stdio_sync .  They work like the xorriso commands with the same name
              and hardcoded parameter "on", e.g. -acl "on".  Explicit parameters are expected  by
              --stdio_sync and --scdbackup_tag.
              The  capability  to  preserve  multi-session  history  on  overwriteable media gets
              disabled by default. It can be enabled by using --emul-toc with the first  session.
              See -compliance no_emul_toc.
              --sort-weight  gets  as parameters a number and an iso_rr_path.  The number becomes
              the LBA sorting weight  of  regular  file  iso_rr_path  or  of  all  regular  files
              underneath directory iso_rr_path.  (See -find -exec sort_weight).
              Adopted  from  grub-mkisofs  are  --protective-msdos-label  (see  -boot_image  grub
              partition_table=on)  and  --modification-date=YYYYMMDDhhmmsscc  (see   -volume_date
              uuid).  For  EFI bootable GRUB boot images use --efi-boot.  It performs -boot_image
              grub efi_path= surrounded by two -boot_image "any" "next".  Alternative  option  -e
              from  Fedora  genisoimage  sets  bin_path  and platform_id for EFI, but performs no
              For MBR bootable ISOLINUX images there is -isohybrid-mbr FILE, where FILE is one of
              the  Syslinux  files  mbr/isohdp[fp]x*.bin  .  Use  this instead of -G to apply the
              effect of -boot_image isolinux partition_table=on.
              --boot-catalog-hide is -boot_image any cat_hidden=on.
              -mips-boot is the same as -boot_image any mips_path= .
              -mipsel-boot leads to mipsel_path= .
              -partition_offset number is -boot_image any partition_offset=number.
              Command -append_partition is supported.
              -untranslated_name_len number is -compliance untranslated_name_len=number.
              --old-empty is -compliance old_empty.
              The options of genisoimage Jigdo Template Extraction are recognized  and  performed
              via  xorriso  command  -jigdo.  See the "Alias:" names there for the meaning of the
              genisoimage options.

              Personalities "xorrisofs", "genisoimage", and "genisofs" are aliases for "mkisofs".
              If xorriso is started with one of the leafnames "xorrisofs", "genisofs", "mkisofs",
              or  "genisoimage",  then it performs -read_mkisofsrc and prepends -as "genisofs" to
              the program arguments.  I.e. all arguments will be interpreted mkisofs style  until
              "--" is encountered.  From then on, arguments are interpreted as xorriso commands.
              --no_rc  as  first  argument  of  such  a  program start prevents interpretation of
              startup files. See section FILES below.

              Personality "cdrecord" accepts the options listed with:
                -as cdrecord -help --
              Among them: -v,  dev=,  speed=,  blank=,  fs=,  -eject,  -atip,  padsize=,  tsize=,
              -isosize,  -multi,  -msinfo,  --grow_overwriteable_iso, write_start_address=, track
              source file path or "-" for standard input as track source.
              It ignores most other options of  cdrecord  and  cdrskin  but  refuses  on  -audio,
              -scanbus, and on blanking modes unknown to xorriso.
              The  scope  is  only  a  single  data  track  per  session  to be written to blank,
              overwriteable, or appendable media. The medium gets closed if closing is applicable
              and not option -multi is present.
              If  an  input  drive was acquired, then it is given up.  This is only allowed if no
              image changes are pending.
              dev= must be given as xorriso device address. Addresses like 0,0,0 or ATA:1,1,0 are
              not supported.
              If  a  track  source  is given, then an automatic -commit happens at the end of the
              "cdrecord" option list.
              --grow_overwriteable_iso enables emulation of multi-session on overwriteable media.
              To enable emulation of a TOC, the first session needs -C 0,32 with -as mkisofs (but
              no -M) and --grow_overwriteable_iso write_start_address=32s with -as cdrecord.
              A much more elaborate libburn based cdrecord emulator is the program cdrskin.
              Personalites "xorrecord", "wodim", and "cdrskin" are aliases for "cdrecord".
              If xorriso is started with one of the leafnames "xorrecord", "cdrskin", "cdrecord",
              or  "wodim", then it automatically prepends -as "cdrskin" to the program arguments.
              I.e. all arguments will be interpreted cdrecord style until  "--"  is  encountered.
              From then on, arguments are interpreted as xorriso commands.
              --no_rc  as  first  argument  of  such  a  program start prevents interpretation of
              xorriso startup files.  See section FILES below.

              Try one by one to open for reading:
               ./.mkisofsrc , $MKISOFSRC , $HOME/.mkisofsrc , $(dirname $0)/.mkisofsrc
              On success interpret the file content as of man mkisofs CONFIGURATION, and end this
              command. Do not try further files.  The last address is used only if start argument
              0 has a non-trivial dirname.
              The  reader   currently   interprets   the   following   NAME=VALUE   pairs:   APPI
              (-application_id)  ,  PUBL  (-publisher) , SYSI (-system_id) , VOLI (-volid) , VOLS
              Any other lines will be silently ignored.

       -pacifier behavior_code
              Control behavior of  UPDATE  pacifiers  during  write  operations.   The  following
              behavior codes are defined:
              "xorriso" is the default format:
              Writing: sector XXXXX of YYYYYY  [fifo active, nn% fill]
              "cdrecord" looks like:
              X of Y MB written (fifo nn%) [buf mmm%]
              nn% done, estimate finish Tue Jul 15 20:13:28 2008
              The frequency of the messages can be adjusted by
              where  number  gives the seconds between two messages. Permissible settings are 0.1
              to 60.0.

       -scdbackup_tag list_path record_name
              Set the parameter "name" for a scdbackup checksum record.  It will be  appended  in
              an  scdbackup  checksum  tag  to the -md5 session tag if the image starts at LBA 0.
              This is the case if it gets written as first session onto a sequential  medium,  or
              piped into a program, named pipe or character device.
              If  list_path  is  not empty then the record will also be appended to the data file
              given by this path.
              Program scdbackup_verify will recognize and verify tag and file record.
              An empty record_name disables this feature.

       Scripting, dialog and program control features:

              Only  if  used  as  first  program  argument  this  command  prevents  reading  and
              interpretation of startup files. See section FILES below.

       -options_from_file fileaddress
              Read  quoted  input from fileaddress and execute it like dialog lines.  Empty lines
              and lines which begin by # are ignored. Normally one line should hold  one  xorriso
              command  and  all  its  parameters.   Nevertheless  lines  may be concatenated by a
              trailing backslash.
              See also section "Command processing", paragraph "Quoted input".

              Print helptext.

              Print program name and version, component versions, license.

       -list_extras code
              Tell whether certain extra features were enabled at compile time.  Code "all" lists
              all  features  and  a  headline.   Other codes pick a single feature.  Code "codes"
              lists them. They share names with related commands (see also there):
              "acl" tells whether xorriso has an adapter for local filesystems ACLs.
              "xattr" tells whether xorriso has an adapter for local filesystems EA.
              "jigdo" tells whether production of Jigdo files is possible.
              "zisofs" tells whether zisofs and built-in gzip filters are enabled.
              "external_filter" tells whether external filter processes are allowed  and  whether
              they are allowed if real user id and effective user id differ.
              "dvd_obs" tells whether 64 kB output to DVD media is default.
              "use_readline" tells whether readline may be enabled in dialog mode.

       -history textline
              Copy textline into libreadline history.

       -status mode|filter
              Print the current settings of xorriso.  Modes:
                short... print only important or altered settings
                long ... print all settings including defaults
                long_history  like long plus history lines
              Filters  begin  with  '-'  and  are  compared literally against the output lines of
              -status:long_history. A line is put out only if its start matches the filter  text.
              No wildcards.

       -status_history_max number
              Set maximum number of history lines to be reported with -status "long_history".

       -list_delimiter word
              Set  the  list  delimiter  to be used instead of "--".  It has to be a single word,
              must not be empty, not longer than 80 characters, and must  not  contain  quotation
              For brevity the list delimiter is referred as "--" throughout this text.

       -sh_style_result "on"|"off"
              Make  the  result  output of some filesystem inspection commands look more like the
              output of equivalent shell commands. The most important effect is  to  prevent  the
              wrapping of file addresses into quotation marks with commands
                -pwd -pwdx -ls -lsd -lsl -lsdl -lsx -lsdx -lslx -lsdlx
                -du -dus -dux -dusx -findx -find
              This  will  make  ambiguous  the representation of file names which contain newline
              characters. On the other hand it should  facilitate  integration  of  xorriso  into
              shell scripts which already use the corresponding shell commands.

       -backslash_codes "on"|"off"|mode[:mode]
              Enable  or  disable  the  interpretation  of  symbolic  representations  of special
              characters with quoted input, or with  program  arguments,  or  with  program  text
              output. If enabled the following translations apply:
               \a=bell(007) \b=backspace(010) \e=Escape(033) \f=formfeed(014)
               \n=linefeed(012) \r=carriage_return(015) \t=tab(011)
               \v=vtab(013) \\=backslash(134) \[0-7][0-7][0-7]=octal_code
               \x[0-9a-f][0-9a-f]=hex_code \cC=control-C
              Translations can occur with quoted input in 3 modes:
               "in_double_quotes" translates only inside " quotation.
               "in_quotes" translates inside " and ' quotation.
               "with_quoted_input" translates inside and outside quotes.
              With the start program arguments there is mode:
               "with_program_arguments" translates program arguments.
              Mode  "encode_output"  encodes output characters. It combines "encode_results" with
              "encode_infos". Inside single or double quotation marks encoding applies  to  8-bit
              characters  octal 001 to 037 , 177 to 377 and to backslash(134).  Outside quotation
              marks  some  harmless  ASCII  control   characters   stay   unencoded:   bell(007),
              backspace(010), tab(011), linefeed(012), formfeed(014), carriage_return(015).
              Mode   "off"   is   default   and   disables   any   translation.    Mode  "on"  is

       -temp_mem_limit number["k"|"m"]
              Set the maximum size of temporary memory to be used for image dependent  buffering.
              Currently this applies to pattern expansion, LBA sorting, restoring of hard links.
              Default is 16m = 16 MiB, minimum 64k = 64 kiB, maximum 1024m = 1 GiB.

       -print  text
              Print a text line to the result channel which is by default stdout.

       -print_info  text
              Print a text line to the info channel which is by default stderr.

       -print_mark  text
              Print  a text line to the mark channel which is by default directed to both, result
              and info channel. An empty text will cause no output at all.

       -prompt text
              Show text at beginning of output line and wait for the user to hit the Enter key or
              to send a line via stdin.

       -sleep seconds
              Wait  for  the  given number of seconds before performing the next command.  Expect
              coarse granularity no better than 1/100 seconds.

       -errfile_log mode path|channel
              If problem events are related to  input  files  from  the  filesystem,  then  their
              disk_paths can be logged to a file or to output channels R or I.
              Mode  can  either be "plain" or "marked". The latter causes marker lines which give
              the time of log start, burn session start, burn session end,  log  end  or  program
              end. In mode "plain", only the file paths are logged.
              If  path  is "-" or "-R" then the log is directed to the result channel.  Path "-I"
              directs it to the info message channel. Any text that does not begin  with  "-"  is
              used as path for a file to append the log lines.
              Problematic  files  can  be recorded multiple times during one program run.  If the
              program run aborts then the list might not be complete  because  some  input  files
              might not have been processed at all.
              The errfile paths are transported as messages of very low severity "ERRFILE".  This
              transport becomes visible with -report_about "ALL".

       -session_log path
              If path is not empty it gives the address of a plain text file where a  log  record
              gets  appended  after each session. This log can be used to determine the start_lba
              of a session for mount options -o sbsector= (on GNU/Linux) or -s (on FreeBSD)  from
              date or volume ID.
              Record format is: timestamp start_lba size volume-id
              The first three items are single words, the rest of the line is the volume ID.

       -scsi_log "on"|"off"
              Mode "on" enables very verbose logging of SCSI commands and drive replies.  Logging
              messages get printed to stderr, not to any of the xorriso output channels.
              A special property of this command is that the first -scsi_log  setting  among  the
              start  arguments  is  in effect already when the first operations of xorriso begin.
              Only "-scsi_log" with dash "-" is recognized that way.

              End program after writing pending changes.

              Discard pending changes. End program immediately.

       # any text
              Only in dialog or file execution mode, and only as first non-whitespace in line: Do
              not execute the line but store it in readline history.

       Support for frontend programs via stdin and stdout:

       -pkt_output "on"|"off"
              Consolidate text output on stdout and classify each line by a channel indicator:
               'R:' for result lines,
               'I:' for notes and error messages,
               'M:' for -mark texts.
              Next  is  a  decimal  number of which only bit 0 has a meaning for now.  0 means no
              newline at end of payload, 1 means that the newline character at  the  end  of  the
              output  line  belongs  to  the payload. After another colon and a blank follows the
              payload text.
               I:1: enter option and parameters :

       -logfile channel fileaddress
              Copy output of a channel to the given file. Channel may be  one  of:  "."  for  all
              channels, "I" for info messages, "R" for result lines, "M" for -mark texts.

       -mark text
              If  text is not empty it will get put out on "M" channel each time xorriso is ready
              for the next dialog line or before xorriso performs a command that was  entered  to
              the pager prompt.

       -msg_op opcode parameter_text
              This command shall facilitate extraction of particular information from the message
              output  of  other   commands.   It   gives   access   to   the   C   API   function
              Xorriso_parse_line()  and  to  the  message  sieve  that  is provided by the C API.
              Please refer to  their  descriptions  in  file  xorriso.h.   Further  it  helps  to
              interpret the severity codes of info messages.
              Intended users are frontend programs which operate xorriso in dialog mode.
              The result output of this command is not caught by the message sieve.
              The following opcodes are defined:
              Install  the  message  sieve  as  of Xorriso_sieve_big() and start watching program
              messages. The parameter_text has no meaning.
              Show a list of filter rule names. The parameter_text  has  no  meaning.   The  list
              begins  by  a  line  with  the return value of Xorriso_sieve_get_result() with flag
              bit3. If this value is larger than 0, then the next line tells the number of names.
              The following lines show one name each.
              Use  the  parameter_text  as  name  of  a filter rule and inquire its next recorded
              result.  See Xorriso_sieve_big() for a list of names and reply strings.
              The recorded strings are put out on result channel. They  get  wrapped  into  lines
              which   tell   their   structure.   The  first  line  tells  the  return  value  of
              Xorriso_sieve_get_result().  The next line tells the number of strings. Each string
              begins  by  a  line that tells the number of lines of the string. Then follow these
              lines. They are to be concatenated with a newline character between each  of  them.
              Finally  the  number  of  still available recorded results of the given name is put
              Dispose  all  recorded  strings  and  continue  watching  program  messages.    The
              parameter_text has no meaning.
              Dispose  the  sieve  with its filter rules and stop watching program messages.  The
              parameter_text has no meaning.
              Read a  text  from  dialog  input  and  submit  it  to  Xorriso_parse_line().   The
              parameter_text word shall consist of several words separated by blanks.  It will be
              necessary to use both kinds of quotation marks.
              E.g. "'ISO session  :' '' 0 0 1"
              The   five   parameter   words   are:   prefix,   separators,   max_words,    flag,
              number_of_input_lines.   The  former  four are handed over to Xorriso_parse_line().
              The number of input lines minus one tells xorriso how many newline  characters  are
              part of the input text.
              The  announced  number  of  text lines will be read from dialog input, concatenated
              with   a   newline   character   between   each   of   them,   and   submitted   to
              Xorriso_parse_line()  as  parameter  line.  Note that newlines outside of quotation
              marks are interpreted as separators if the separators parameter is empty.
              The parsed strings are put out on result channel. They get wrapped into lines which
              tell   their   structure.    The   first   line   tells   the   return   value   of
              Xorriso_parse_line().  The next line tells  the  number  of  strings.  Each  string
              begins  by  a  line that tells the number of lines of the string. Then follow these
              lines. They are to be concatenated with a newline character between each of them.
              If -backslash_codes "encode_output" is enabled, then the strings  undergo  encoding
              as  if  they  were enclosed in quotes. Escpecially each string will be put out as a
              single result line.
              Like "parse", but with the fifth parameter word being number_of_input_texts  rather
              than number_of_input_lines. Each input text has to be preceded by a line that tells
              number_of_input_lines as with "parse".  Then come  the  announced  number  of  text
              All input texts will be read before printing of result lines begins.  This consumes
              memory in xorriso. So the number_of_input_texts should not be  extremely  high.  On
              the  other  hand,  large  transactions  of  command,  input  texts, and results are
              desirable if connection latency is an issue.
              Like "parse" but not issuing a prompting message. Confusing to humans.
              Like "parse_bulk" but not issuing a prompting message. Confusing to humans.
              The parameter_text should contain two comma separated severity texts as  issued  by
              this program. Like "SORRY,UPDATE". See also paragraph "Exception processing".
              These  two  severity  texts  get  compared  and a number gets printed to the result
              channel. This number is 0 if both severities are equal.  It  is  -1  if  the  first
              severity  is  lower  than  the second one.  It is 1 is the first severity is higher
              than the second one.
              Above example "SORRY,UPDATE" will yield 1.
              Print to the result channel a blank separated list of all severity  names.   Sorted
              from low to high severity.

       -named_pipe_loop mode[:mode] disk_path_stdin disk_path_stdout disk_path_stderr
              Temporarily  replace  standard  input,  standard output and standard error by named
              pipes. Enter dialog mode without readline.
              Defined modes are:
              "cleanup" removes the submitted pipe files when the loop ends.
              "keep" does not delete them. This is the default.
              "buffered" reads all lines from the input pipe until EOF before it opens the output
              pipes and processes the input lines.
              "direct"  opens the output pipes after the first input line was read.  Each line is
              executed directly after it is read. This is the default.
              The other three parameters must either be disk paths to existing named pipes, or be
              "-" to leave the according standard i/o channel unreplaced.
              xorriso  will  open the stdin pipe, read and execute dialog lines from it until the
              sender closes the pipe. The output pipes get opened depending on mode "buffered" or
              "direct".  After  all  lines are executed, xorriso will close its side of the pipes
              and enter a new cycle of opening, reading and executing.
              If  an  input  line  consists  only  of   the   word   "end_named_pipe_loop"   then
              -named_pipe_loop  will  end and further xorriso commands may be executed from other

       -launch_frontend program [arguments ...] --
              Start the program that is given as first parameter. Submit the other parameters  as
              program arguments. Enable xorriso dialog mode.
              Two nameless pipe objects are created. xorriso standard input gets connected to the
              standard output of the started program.  xorriso standard output and standard error
              get connected to the standard input of that program.
              xorriso will abort when the started program ends or if it cannot be started at all.
              In both cases it will return a non-zero exit value.  The exit value will be zero if
              the frontend sends -end or -rollback_end before ending itself.
              This  command  may  be  totaly  banned  at compile time. It is banned by default if
              xorriso runs under setuid permissions.
              The program name will not be searched in  the  $PATH  directories.   To  make  this
              clear, it must contain at least one /-character.  Best is an absolute path.
                xorriso -launch_frontend "$(which xorriso-tcltk)" -stdio --
              The frontend program should first send via its standard output:
                -mark 0 -pkt_output on -msg_op start_sieve - -reassure off
              It  should  be ready to decode -pkt_output and to react on -mark messages.  Best is
              to increment the -mark number after each sent command sequence and then to wait for
              the new number to show up in a mark message:
                ...some...commands... -mark <incremented_number>
              Further are advised:
                -report_about UPDATE -abort_on NEVER
                -iso_rr_pattern off -disk_pattern off
              A  check  of  the  xorriso  version  should be done, in order to make sure that all
              desired features are present.
              Command -launch_frontend will only work  once  per  xorriso  run.   If  no  command
              parameters  are  submitted  or if program is an empty text, then no program will be
              started but nevertheless -launch_frontend will be irrevocably disabled.

       -prog text
              Use text as name of this program in subsequent messages

       -prog_help text
              Use text as name of this program and perform -help.


   Overview of examples:
       As superuser learn about available drives
       Blank medium and compose a new ISO image as batch run
       A dialog session doing about the same
       Manipulate an existing ISO image on the same medium
       Copy modified ISO image from one medium to another
       Bring a prepared ISOLINUX tree onto medium and make it bootable
       Change existing file name tree from ISO-8859-1 to UTF-8
       Operate on storage facilities other than optical drives
       Burn an existing ISO image file to medium
       Perform multi-session runs as of cdrtools traditions
       Let xorriso work underneath growisofs
       Adjust thresholds for verbosity, exit value and program abort
       Examples of input timestrings
       Incremental backup of a few directory trees
       Restore directory trees from a particular ISO session to disk
       Try to retrieve blocks from a damaged medium

   As superuser learn about available drives
       On Linux, FreeBSD or NetBSD consider to give rw-permissions to those users or groups which
       shall be able to use the drives with xorriso.  On Solaris use pfexec. Consider to restrict
       privileges of xorriso to "base,sys_devices" and to give r-permission to user or group.
       $ xorriso -device_links
       1  -dev '/dev/cdrom1' rwrw-- :  'TSSTcorp' 'DVD-ROM SH-D162C
       1  -dev '/dev/cdrw'   rwrw-- :  'TSSTcorp' 'CDDVDW SH-S223B'
       2  -dev '/dev/cdrw3'  rwrw-- :  'HL-DT-ST' 'BDDVDRW_GGC-H20L'

   Blank medium and compose a new ISO image as batch run
       Acquire drive /dev/sr2, make medium ready for writing a new image, fill the image with the
       files from hard disk directories /home/me/sounds and /home/me/pictures.
       Because  no -dialog "on" is given, the program will then end by writing the session to the
       $ xorriso -outdev /dev/sr2 \
        -blank as_needed \
        -map /home/me/sounds /sounds \
        -map /home/me/pictures /pictures

       The ISO image may be shaped in a more elaborate way like the following: Omit some unwanted
       stuff by removing it from the image directory tree.  Reintroduce some wanted stuff.
       $ cd /home/me
       $ xorriso -outdev /dev/sr2 \
        -blank as_needed \
        -map /home/me/sounds /sounds \
        -map /home/me/pictures /pictures \
        -rm_r \
          /sounds/indecent \
          '/pictures/*private*' \
          /pictures/confidential \
          -- \
        -cd / \
        -add pictures/confidential/work* --
       Note    that    '/pictures/*private*'    is    a    pattern    for    iso_rr_paths   while
       pictures/confidential/work* gets expanded by the shell with addresses from the hard  disk.
       Commands  -add  and  -map have different parameter rules but finally the same effect: they
       put files into the image.

   A dialog session doing about the same
       Some settings are already given as start argument. The other activities are done as dialog
       input. The pager gets set to 20 lines of 80 characters.
       The  drive  is  acquired  by  command -dev rather than -outdev in order to see the message
       about its current content. By  command  -blank  this  content  is  made  ready  for  being
       overwritten and the loaded ISO image is made empty.
       In order to be able to eject the medium, the session needs to be committed explicitly.
       $ xorriso -dialog on -page 20 80 -disk_pattern on
       enter option and arguments :
       -dev /dev/sr2
       enter option and arguments :
       -blank as_needed
       enter option and arguments :
       -map /home/me/sounds /sounds -map /home/me/pictures /pictures
       enter option and arguments :
       -rm_r /sounds/indecent /pictures/*private* /pictures/confidential
       enter option and arguments :
       -cdx /home/me/pictures -cd /pictures
       enter option and arguments :
       -add confidential/office confidential/factory
       enter option and arguments :
       -du /
       enter option and arguments :
       -commit_eject all -end

   Manipulate an existing ISO image on the same medium
       Load image from drive.  Remove (i.e. hide) directory /sounds and its subordinates.  Rename
       directory /pictures/confidential to /pictures/restricted.  Change  access  permissions  of
       directory /pictures/restricted.  Add new directory trees /sounds and /movies.  Burn to the
       same medium, check whether the tree can be loaded, and eject.
       $ xorriso -dev /dev/sr2 \
        -rm_r /sounds -- \
        -mv \
          /pictures/confidential \
          /pictures/restricted \
          -- \
        -chmod go-rwx /pictures/restricted -- \
        -map /home/me/prepared_for_dvd/sounds_dummy /sounds \
        -map /home/me/prepared_for_dvd/movies /movies \
        -commit -eject all

   Copy modified ISO image from one medium to another
       Load image from input drive. Do the same manipulations as in the previous example. Acquire
       output drive and blank it. Burn the modified image as first and only session to the output
       $ xorriso -indev /dev/sr2 \
        -rm_r /sounds -- \
        -outdev /dev/sr0 -blank as_needed \
        -commit -eject all

   Bring a prepared ISOLINUX tree onto medium and make it bootable
       The user has already created a suitable file tree on disk and copied  the  ISOLINUX  files
       into  subdirectory  ./boot/isolinux  of  that  tree.   Now  xorriso  can burn an El Torito
       bootable medium:
       $ xorriso -outdev /dev/sr0 -blank as_needed \
          -map /home/me/ISOLINUX_prepared_tree / \
          -boot_image isolinux dir=/boot/isolinux

   Change existing file name tree from ISO-8859-1 to UTF-8
       This example assumes that the existing ISO image was written with character set ISO-8859-1
       but  that  the  readers  expected  UTF-8. Now a new session gets added with converted file
       names.   Command  -changes_pending  "yes"  enables  writing  despite  the  lack   of   any
       manipulation command.
       In order to avoid any weaknesses of the local character set, this command pretends that it
       uses already the final target set UTF-8.  Therefore  strange  file  names  may  appear  in
       messages, which will be made terminal-safe by command -backslash_codes.
       $ xorriso -in_charset ISO-8859-1 -local_charset UTF-8 \
          -out_charset UTF-8 -backslash_codes on -dev /dev/sr0 \
          -changes_pending yes -commit -eject all

   Operate on storage facilities other than optical drives
       Full read-write operation is possible with regular files and block devices:
       $ xorriso -dev /tmp/regular_file ...
       Paths underneath /dev normally need prefix "stdio:"
       $ xorriso -dev stdio:/dev/sdb ...
       If  /dev/sdb  is  to  be used frequently and /dev/sda is the system disk, then consider to
       place the following lines in a xorriso Startup File.   They  allow  you  to  use  /dev/sdb
       without prefix and protect disk /dev/sda from xorriso:
         -drive_class banned   /dev/sda*
         -drive_class harmless /dev/sdb
       Other writeable file types are supported write-only:
       $ xorriso -outdev /tmp/named_pipe ...
       Among the write-only drives is standard output:
       $ xorriso -outdev - \
        | gzip >image.iso.gz

   Burn an existing ISO image file to medium
       Actually this works with any kind of data, not only ISO images:
       $ xorriso -as cdrecord -v dev=/dev/sr0 blank=as_needed image.iso

   Perform multi-session runs as of cdrtools traditions
       Between both processes there can be performed arbitrary transportation or filtering.
       The first session is written like this:
       $ xorriso -as mkisofs prepared_for_iso/tree1 | \
        xorriso -as cdrecord -v dev=/dev/sr0 blank=fast -multi -eject -
       Follow-up sessions are written like this (the run of dd is only to give demons a chance to
       spoil it):
       $ m=$(xorriso -as cdrecord dev=/dev/sr0 -msinfo)
       $ dd if=/dev/sr0 count=1 >/dev/null 2>&1
       $ xorriso -as mkisofs -M /dev/sr0 -C $m prepared_for_iso/tree2 | \
        xorriso -as cdrecord -v dev=/dev/sr0 -waiti -multi -eject -
       Always eject the drive tray between sessions.
       The run of xorriso -as mkisofs will read old sessions via the CD-ROM driver  of  /dev/sr0.
       This  driver might not be aware of the changed content as long as the medium is not loaded
       again. In this case the previous session would not be properly assessed by xorriso and the
       new session would contain only the newly added files.
       Some  systems  have  not  enough  patience with automatic tray loading and some demons may
       interfere with a first CD-ROM driver read attempt from a freshly loaded medium.
       When loading the tray manually, wait 10 seconds after the drive has stopped blinking.
       A safe automatic way seems to be a separate run of  xorriso  for  loading  the  tray  with
       proper waiting, and a subsequent run of dd which shall offer itself to any problems caused
       by demons assessing the changed drive status.  If this does not  help,  insert  a  run  of
       "sleep 10" between xorriso and dd.
       This    example    works    for    multi-session   media   only.    Add   cdrskin   option
       --grow_overwriteable_iso to all  -as  cdrecord  runs  in  order  to  enable  multi-session
       emulation on overwriteable media.

   Let xorriso work underneath growisofs
       growisofs expects an ISO formatter program which understands options -C and -M. If xorriso
       gets started by name "xorrisofs" then it is suitable for that.
       $ 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 -- outdev - -update_r /my/files /files
       $ growisofs -M /dev/dvd -- outdev - -update_r /my/files /files
       growisofs  has  excellent  burn capabilities with DVD and BD.  It does not emulate session
       history on overwriteable media, though.

   Adjust thresholds for verbosity, exit value and program abort
       Be quite verbose, exit 32 if severity "FAILURE" was encountered, do not abort  prematurely
       but forcibly go on until the end of commands.
       $ xorriso ... \
        -report_about UPDATE \
        -return_with FAILURE 32 \
        -abort_on NEVER \

   Examples of input timestrings
       As printed by program date: 'Thu Nov 8 14:51:13 CET 2007'
       The same without ignored parts: 'Nov 8 14:51:13 2007'
       The same as expected by date: 110814512007.13
       Four weeks in the future: +4w
       The current time: +0
       Three hours ago: -3h
       Seconds since Jan 1 1970: =1194531416

   Incremental backup of a few directory trees
       This  changes  the  directory  trees /projects 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.  Accelerated comparison is
       enabled at the expense of potentially larger backup size. Only  media  with  the  expected
       volume  ID  or  blank  media  are  accepted.   Files  with names matching *.o or *.swp get
       excluded explicitly.
       When done with writing the new session gets checked by its recorded MD5.
       $ xorriso \
        -abort_on FATAL \
        -for_backup -disk_dev_ino on \
        -assert_volid 'PROJECTS_MAIL_*' FATAL \
        -dev /dev/sr0 \
        -volid PROJECTS_MAIL_"$(date '+%Y_%m_%d_%H%M%S')" \
        -not_leaf '*.o' -not_leaf '*.swp' \
        -update_r /home/thomas/projects /projects \
        -update_r /home/thomas/personal_mail /personal_mail \
        -commit -toc -check_md5 FAILURE -- -eject all
       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 the run fails
       gracefully due to lack of remaining space on the old one.
       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.  To apply zisofs compression
       to those data files which get  newly  copied  from  the  local  filesystem,  insert  these
       commands immediately before -commit :
        -hardlinks perform_update \
        -find / -type f -pending_data -exec set_filter --zisofs -- \
       Commands  -disk_dev_ino and -for_backup depend on stable device and inode numbers on disk.
       Without them, an update run may use -md5 "on" to  match  recorded  MD5  sums  against  the
       current  file  content  on  hard  disk. This is usually much faster than the default which
       compares both contents directly.
       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  command  -toc.  Used after -commit the following command
       prints the matching mount command for the newly written  session  (here  for  mount  point
        -mount_cmd "indev" "auto" "auto" /mnt
       Commands  -mount_cmd  and  -mount  are  also  able to produce the mount commands for older
       sessions in the table-of-content. E.g. as superuser:
        # osirrox -mount /dev/sr0 "volid" '*2008_12_05*' /mnt

       Above example produces a result similar to  -root / -old-root / with mkisofs.  For getting
       the  session  trees accumulated in the new sessions, let all -update commands use a common
       parent directory and clone it after updating is done:
        -update_r /home/thomas/projects /current/projects \
        -update_r /home/thomas/personal_mail /current/personal_mail \
        -clone /current /"$(date '+%Y_%m_%d_%H%M%S')" \
       The cloned tree will have a name like /2011_02_12_155700.

       Sessions on multi-session media are separated by several MB of  unused  blocks.   So  with
       small  sessions the payload capacity can become substantially lower than the overall media
       capacity. If the remaining space on a medium does not suffice for the next gap, the  drive
       is supposed to close the medium automatically.

       Better  do  not use your youngest backup for -update_r.  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

   Restore directory trees from a particular ISO session to disk
       This is an alternative to mounting the medium and using normal file operations.
       First check which backup sessions are on the medium:
       $ xorriso -outdev /dev/sr0 -toc
       Then  enable restoring of ACL, xattr and hard links. Load the desired session and copy the
       file trees to disk.  Avoid to create /home/thomas/restored without rwx-permission.
       $ xorriso -for_backup \
        -load volid 'PROJECTS_MAIL_2008_06_19*' \
        -indev /dev/sr0 \
        -osirrox on:auto_chmod_on \
        -chmod u+rwx / -- \
        -extract /projects /home/thomas/restored/projects \
        -extract /personal_mail /home/thomas/restored/personal_mail \
       The final command -rollback_end prevents an error message about the  altered  image  being

   Try to retrieve blocks from a damaged medium
       $ xorriso -abort_on NEVER -indev /dev/sr0 \
        -check_media time_limit=1800 report=blocks_files \
        data_to="$HOME"/dvd_copy sector_map="$HOME"/ --
       This  can be repeated several times, if necessary with -eject or with other -indev drives.
       See the human readable part of "$HOME"/ for addresses which  can  be  used  on
       "$HOME"/dvd_copy with mount option -o sbsector= or -s.


   Program alias names:
       Normal  installation  of xorriso creates three links or copies which by their program name
       pre-select certain settings:
       xorrisofs starts xorriso with -as mkisofs emulation.
       xorrecord starts xorriso with -as cdrecord emulation.
       osirrox starts with -osirrox "on:o_excl_off" which allows further commands to  copy  files
       from  ISO  image  to  disk  and to apply command -mount to one or more of the existing ISO

   Startup files:
       If not -no_rc is given as the first argument then xorriso attempts on startup to read  and
       execute lines from the following files:
       The files are read in the sequence given above, but none of them is required to exist. The
       line format is described with command -options_from_file.
       If mkisofs emulation was enabled by program name "xorrisofs", "mkisofs", "genisoimage", or
       "genisofs",  then  afterwards  -read_mkisofsrc is performed, which reads .mkisofsrc files.
       See there.

   Runtime control files:
       The default setting of -check_media abort_file= is:


       The following environment variables influence the program behavior:
       HOME is used to find startup files of xorriso and mkisofs.
       SOURCE_DATE_EPOCH belongs to the specs of  It is supposed  to  be
       either  undefined or to contain a decimal number which tells the seconds since january 1st
       1970. If it contains a number, then it is used as time value to set the default of -volume
       date  "uuid",  sets -boot_image "any" "gpt_disk_guid=" to "volume_date_uuid", -volume_date
       "all_file_dates" to "set_to_mtime", and -iso_nowtime to "=$SOURCE_DATE_EPOCH".
       Startup files and program options can override the effect of SOURCE_DATE_EPOCH.


       For the mkisofs emulation of xorriso

       For the cdrecord emulation of xorriso

       For mounting xorriso generated ISO 9660 images (-t iso9660)

       Libreadline, a comfortable input line facility

       Other programs which produce ISO 9660 images
              mkisofs(8), genisoimage(1)

       Other programs which burn sessions to optical media
              growisofs(1), cdrecord(1), wodim(1), cdrskin(1)

       ACL and xattr
              getfacl(1), setfacl(1), getfattr(1), setfattr(1)

       MD5 checksums

       On FreeBSD the commands for xattr and MD5 differ
              getextattr(8), setextattr(8), md5(1)


       To report bugs, request help, or suggest enhancements for xorriso, please send  electronic
       mail  to  the  public  list  <>.   If  more privacy is desired, mail to
       Please describe what you expect xorriso to do, the program arguments or dialog commands by
       which  you  tried  to  achieve it, the messages of xorriso, and the undesirable outcome of
       your program run.
       Expect to get asked more questions before solutions can be proposed.


       Thomas Schmitt <>


       Copyright (c) 2007 - 2019 Thomas Schmitt
       Permission is granted to distribute this text freely. It shall only be  modified  in  sync
       with  the  technical  properties  of  xorriso.   If  you make use of the license to derive
       modified versions of xorriso then you are entitled to modify this  text  under  that  same


       xorriso  is  in  part  based on work by Vreixo Formoso who provides libisofs together with
       Mario Danic who also leads the libburnia team.  Vladimir Serbinenko contributed  the  HFS+
       filesystem  code  and  related  knowledge.   Thanks to Andy Polyakov who invented emulated
       growing, to Derek Foreman and Ben Jansens who once founded libburn.
       Compliments towards Joerg Schilling whose cdrtools served me for ten years.

                                   Version 1.5.2, Nov 26, 2019                         XORRISO(1)