Provided by: xorriso_1.3.2-1ubuntu1_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  allows  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 allows to add 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
       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 allowing 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 allow 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  allow  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 resp. 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.

       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
       On FreeBSD the device files have names like
         -dev /dev/cd0
       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 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  allow  only  MMC
       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 partiton 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.   Those  are mutually not combinable and also not combinable with MBR, GPT, or

       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 allows to  record  and  restore  pairs
       which  have  names  out  of  the user namespace. I.e. those which begin with "user.", like
       "user.x" or "user.whatever". 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 -xattr.
       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 allow 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  allows  to 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.

       -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.

       -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
              Adressing 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 -displacement 160000.
              In both cases, the ISO sessions should be self contained, i.e. not add-on  sessions
              to an ISO image outside their track resp. partition.

       -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.

       -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"|"off"
              Enable or disable processing of xattr attributes in user  namespace.   If  enabled,
              then  xorriso  will  handle  xattr  similar  to  ACL.  See also commands -getfattr,
              -setfattr and above paragraph about xattr.

       -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 on -md5 on.

       -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 allow to 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",

       -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, resp.  both.   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 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"  then  pattern  expansion  is always disabled and
              character '=' has a special meaning. It separates the ISO image path from the  disk
              The  separator  '='  can be escaped by '\'.  If iso_rr_path does not begin with '/'
              then -cd is prepended.   If  disk_path  does  not  begin  with  '/'  then  -cdx  is
              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 resp. 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.

       -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)   resp.   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 resp. -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, and to -disk_pattern expansion.
              There are two kinds of follow decisison to be made:
              "link" is the hop from a symbolic link to its target file object.  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 traversals.
              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".

              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"
              Control parameter interpretation with xorriso actions -add and -path_list.
              "on"  enables  pathspecs  of  the  form  target=source  like  with  program mkisofs
              -graft-points.  It also disables -disk_pattern expansion for command -add.
              "off" disables pathspecs of the form  target=source  and  re-enables  -disk_pattern

       -overwrite "on"|"nondir"|"off"
              Allow  or  disallow  to overwrite existing files in the ISO image by files with the
              same name.
              With setting "off", name collisions cause FAILURE events.  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"  allows  automatic
              -rm_r.  I.e.  a  non-directory  can  replace  an  existing  directory  and  all its
              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 resp. 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   -ossirox  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 resp. group id. After  the  second
              ":"  there  may be letters out of {rwx- #}.  The first three give read, write resp.
              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.
              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.
              Only names from the user namespace are allowed. I.e.  a  name  has  to  begin  with
              "user.", like "user.x" or "user.whatever".
              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  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
              user  space  xattr  of the given iso_rr_paths will be deleted.  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
              Name  must  be  from  user  namespace.  I.e.  where xyz should consist of
              printable characters only. 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 a file in the ISO image. type is one of "a", "m", "b" for
              access time, modification time, both times.
              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_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.
              -wholename pattern : Matches if pattern matches  the  file  path  as  it  would  be
              printed  by  action  "echo".  Character  '/'  is  not special but can be matched by
              -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
              -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".
              -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.
              -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 resp. match not. 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" --
              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 is very large. In
              this case each line has a different extent number in column "xt".
              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 from user namespace to the result channel.
              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.
              E.g.: -exec sort_weight 3 --
              show_stream shows the content stream chain of a data file.
              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
              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  -external_filter  and   -unregister_filter,   but   not
              -set_filter. Use this to prevent external filtering in general or when all intended
              filters are registered.  External filters may also be  banned  totally  at  compile
              time  of  xorriso.   By  default  they  are  banned  if  xorriso  runs under setuid

       -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 explicitely
              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,  resp. -outdev, resp. both drives.  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 occured.
              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 occured. 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  output  drive  with  the  loaded
              medium.  This  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 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".

       -close_damaged "as_needed"|"force"
              Try to close the upcomming 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, resp. -outdev, resp. both.  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.
              "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.
              "uuid"   sets  a  timestring  that  overrides "c" and "m" times literally.  It must
              consist of 16 decimal digits which form YYYYMMDDhhmmsscc, with  YYYY  between  1970
              and 2999. Time zone is GMT.  It is supposed to match this GRUB line:
               search --fs-uuid --set YYYY-MM-DD-hh-mm-ss-cc
              E.g. 2010040711405800 is 7 Apr 2010 11:40:58 (+0 centiseconds).
              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.

       -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 number[k|m|c|d|b]
              Set  the  burn  speed.  Default  is 0 = maximum speed.  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 explicity 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.

       -stdio_sync "on"|"off"|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

       -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"
              If "on" then mark the written medium as not appendable any more (if possible at all
              with the given type of target media).
              This  is the contrary of cdrecord, wodim, cdrskin command -multi, and is one aspect
              of growisofs option -dvd-compat.

       -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
              explicitely  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.
       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 for hard-disk-like devices, MIPS Volume  Header  for
       old SGI computers, DEC Boot Block for old DECstation, SUN Disk Label for SPARC machines.
       The boot firmware EFI may use programs which are located in a FAT filesystem and announced
       by an MBR partition table entry.

       -boot_image "any"|"isolinux"|"grub"
              Define the handling of a set of El Torito boot images which has been read  from  an
              existing  ISO  image or define how to make a prepared boot image file set bootable.
              Such file sets get produced by 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.

              El  Torito boot images of any type can be newly inserted, or discarded, or patched,
              or kept unaltered.  Whether to patch or to keep depends on whether the boot  images
              contain boot info tables.
              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).
              Most safe is the default: -boot_image "any" "discard".
              Advised for GRUB :  -boot_image "grub" "patch"
              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 image by an El Torito record or a  MBR.   The  names  "dir",  "bin_path",
              "efi_path" lead to El Torito bootable images.  Name "system_area" activates a given
              file as MBR.
              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.
              The boot image and its supporting files 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= 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".
              bin_path= depicts a 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 a boot image file that is ready for EFI booting.   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  2048  should  be
              overridden only if a better value is known.
              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 two hex digits the Platform ID of the boot image. "00" is
              80x86 PC-BIOS, "01" is PowerPC, "02" is Mac, "ef" is EFI.
              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.
              discard gives up an existing boot catalog and its boot images.
              keep keeps or copies boot images unaltered and writes a new catalog.
              patch applies patching to existing boot images if they seem to  bear  a  boot  info
              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 a 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".
              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.
              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.
              In  follow-up  sessions the existing System Area is preserved by default.  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.
              chrp_boot_part=on causes a single partition in MBR which covers the whole ISO image
              and  has type 0x41. This is not compatible with any other feature that produces MBR
              partition entries. It makes GPT unrecognizable.
              prep_boot_part= inserts the content of a data file into the image and marks  it  by
              an  MBR  partition  of  type 0x96. 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=  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 allow exact alignment.  If it is too  small
              to  describe  the  image size by at most 1024 cylinders, 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.
              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.
              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.
              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. This boot block format allows to append images for partitions 2 to 8.
              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.
              mips_discard and sparc_discard revoke any boot file declarations made by mips_path=
              or  mipsel_path=. They also disable production of SUN Disk Label.  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 codes
              search the Internet for "Partition Types" or run fdisk command "L".
              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 .md5 file which lists those data files which may be listed in the  .jigdo  file  and
       externally  referenced  in the .template file.  Each designated file is represented in the
       .md5 file by a single text line:
       MD5 as 32 hex digits, 2 blanks, size as 12 decimal digits or blanks,  2  blanks,  symbolic
       file address
       The  file  address  in  an .md5 line has to bear the same basename as the disk_path of the
       file which it shall match. The directory path of the file address is decisive for  To=From
       mapping,  not  for file recognition.  After To=From mapping, the file address gets written
       into the .jigdo file. Jigdo  restore  tools  will  convert  these  addresses  into  really
       reachable data source addresses from which they can read.
       If  the  list  of  jigdo  parameters  is  not  empty, then 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.
              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
              md5_path sets the disk_path where to find the .md5 input file.
              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_md5 adds a regular expression pattern  which  will  get  compared  with  the
              absolute  disk_path  of  any data file that was not found in the .md5 list. A match
              causes a MISHAP event.
              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 .md5 file. This file address gets checked whether  it  begins  with
              the  From  string.  If so, then this string will be replaced by the To string and a
              ':' character, before it goes into the .jigdo file. The From string should end by a
              '/' character.
              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.
       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 character
       set.  Outside these constraints it may be necessary to let xorriso convert byte codes.
       There is an input conversion from input character set to the  local  character  set  which
       applies when an ISO image gets loaded. A conversion from local character set to the output
       character set is performed when an image tree  gets  written.  The  sets  can  be  defined
       independently  by  commands  -in_charset  and  -out_charset.  Normally  one will have both
       identical, if ever.
       If conversions are desired then xorriso needs to know the name of the local character set.
       xorriso  can inquire the same info as 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.
       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  names  in
       the  image.  The  situation stays ambigous 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 unambigous. 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 resp. 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 aquired and not the same, then both
              tables-of-content get shown.

       -toc_of "in"|"out"|"all"[":short"]
              Like command -toc but explicitely 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 aquired.

       -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.
              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
              entity  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 any text as id.
              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 allow to mount 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, resp. 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.

       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",
              resp.  'H'  for  multiple  hiding gets appended.  Together with ACL it is 'i', 'j',
              'a', resp. '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.

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

       -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 successfuly 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=valid 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.
              retry="on" forces read retries with  single  blocks  when  the  normal  read  chunk
              produces  a  read  error.  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 allows to do 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
              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",
              "invalid", "tao_end", "off_track", "md5_mismatch", "unreadable".
              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.
              chunk_size=size  sets  the  number of bytes to be read in one read operation.  This
              gets rounded down to full blocks of 2048 bytes. 0 means automatic size.
              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 allows to
              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" allows on GNU/Linux to access such
              drives. 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 allow handling of large files if they are
              not supported by mount -t iso9660 and if the reading system  is  unable  to  buffer
              them as a whole.
              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

       -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.
              -pacifier gets set to "mkisofs" if files are added to the image.
              -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 resp. 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 resp. record.

       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  ambigous  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
              resp. to send a line via stdin.

       -sleep seconds
              Wait  for  the  given  number of seconds before perfoming 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= resp. -s 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 verbous 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 inbetween 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   inbetween   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 inbetween 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 issueing a prompting message. Confusing to humans.
              Like "parse_bulk" but not issueing 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"
              resp. "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  or FreeBSD 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 with the same files gets added with
       converted  file  names.  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
       $ xorriso -in_charset ISO-8859-1 -local_charset UTF-8 \
          -out_charset UTF-8 -backslash_codes on -dev /dev/sr0 \
          -alter_date m +0 / -- -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 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:
       $ dd if=/dev/sr0 count=1 >/dev/null 2>&1
       $ m=$(xorriso -as cdrecord dev=/dev/sr0 -msinfo)
       $ 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 old sessions get read via /dev/sr0.  Its
       device  driver might not be aware of the changed content before it loads the medium again.
       In this case the previous session would not be loaded and the new  session  would  contain
       only the newly added files.
       For  the  same  reason do not let xorriso -as cdrecord load the medium, but rather do this
       manually or by a program that reads from /dev/sr0.
       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 verbous, 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 resp. -s on FreeBSD 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= resp. -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 to copy files from ISO image to
       disk and to apply command -mount to one or more of the existing ISO sessions.

   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:


       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(8)

       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  resp.  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 - 2013 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 1.3.2, Aug 07, 2013                         XORRISO(1)