MKISOFS(8)

πŸ“¦
version 3.02a09 Β· 2 versions
, in arch rolling

πŸ’Ώ MKISOFS(8) ✨

okay so this is mkisofs from the System Manager's Manual, and bestie, we are about to make a whole filesystem image together 🫢


πŸŽ€ NAME πŸŽ€

mkisofs β€” create an hybrid ISO-9660/JOLIET/HFS/UDF filesystem-image with optional Rock Ridge attributes. that's the whole vibe, periodt πŸ’…


⭐ SYNOPSIS ⭐

mkisofs [ options ] [ -o filename ] pathspec [pathspec ...]
mkisofs [ options ] [ -o filename ] -find [find expression]

🌸 DESCRIPTION 🌸

so mkisofs is effectively a pre-mastering program to generate an ISO-9660/JOLIET/HFS/UDF hybrid filesystem. yes, that's a lot of slashes, i know, breathe 🧚

ISO-9660/JOLIET/UDF filesystems are limited to a maximum size of 8 TB. the maximum size of a single file is 8 TB β€” and single files in UDF are currently limited to aprox. 200 GB. if you like to have files larger than 2 GB, you need to specify -iso-level 3 or above. and if a HFS hybrid is created, the maximum file size for files in the HFS hybrid is 2 GB in any case. so like… know your limits, babes πŸ’€

πŸ¦‹ Hybrid filesystem support πŸ¦‹

mkisofs is capable of generating the System Use Sharing Protocol records (SUSP) specified by the Rock Ridge Interchange Protocol. this is used to further describe the files in the ISO-9660 filesystem to a UNIX host, and provides information such as longer filenames, uid/gid, posix permissions, symbolic links, hard links, block and character devices. the way that's literally everything a UNIX host wants to know πŸ‘‘

if Joliet, HFS or UDF hybrid command line options are specified, mkisofs will create additional separate filesystem meta data for Joliet, HFS or UDF. the file content in this case refers to the same data blocks on the media. it will generate a pure ISO-9660 filesystem unless the Joliet, HFS or UDF hybrid command line options are given. so it's not doing all that extra work unless you actually ask πŸ’…

mkisofs can generate a true (or shared) HFS hybrid filesystem. the same files are seen as HFS files when accessed from a Macintosh and as ISO-9660 files when accessed from other machines. HFS stands for Hierarchical File System and is the native file system used on Macintosh computers up to Mac OS 9. retro icon behavior fr fr πŸ“

as an alternative, mkisofs can generate the Apple Extensions to ISO-9660 or UDF for each file. these extensions provide each file with CREATOR, TYPE and certain Finder Flags when accessed from a Macintosh. see the HFS MACINTOSH FILE FORMATS section below πŸ‘€

🧚 Functional description 🧚

mkisofs takes a snapshot of a given directory tree, and generates a binary image which will correspond to an ISO-9660 or Joliet/HFS/UDF filesystem when written to a block device. main character energy: it literally just captures the moment 🌈

each file written to the ISO-9660 filesystem must have a filename in the 8.3 format (8 characters, period, 3 characters, all upper case), even if Rock Ridge attributes are in use. this filename is used on systems that are not able to make use of the Rock Ridge extensions (such as MS-DOS), and each filename in each directory must be different from the other filenames in the same directory. mkisofs generally tries to form correct names by forcing the UNIX filename to upper case and truncating as required, but often times this yields unsatisfactory results when there are cases where the truncated names are not all unique. sad but true 😭

mkisofs assigns weightings to each filename, and if two names that are otherwise the same are found the name with the lower priority is renamed to have a 3 digit number as an extension (where the number is guaranteed to be unique). an example of this would be the files foo.bar and foo.bar.~1~ β€” the file foo.bar.~1~ would be written as FOO000.BAR;1 and the file foo.bar would be written as FOO.BAR;1. see? it ate and left no crumbs ✨

when used with various HFS or UDF options, mkisofs will attempt to recognise files stored in a number of Apple/Unix file formats and will copy the data and resource forks as well as any relevant finder information. see the HFS MACINTOSH FILE FORMATS section below for more about formats mkisofs supports πŸŽ€

note that mkisofs is not designed to communicate with writers for optical media directly. most writers have proprietary command sets which vary from one manufacturer to another, and you need a specialized tool like cdrecord to actually burn the disk. it's giving "i make the image, you do the burning" πŸ’…

the cdrecord utility is a utility capable of burning an actual disc. the latest version of cdrecord is available from https://sourceforge.net/projects/cdrtools/files/ or https://sourceforge.net/projects/cdrtools/files/alpha/ πŸ”₯

also you should know that most CD writers are very particular about timing. once you start to burn a disc, you cannot let their buffer empty before you are done, or you will end up with a corrupt disc. thus it is critical that you be able to maintain an uninterrupted data stream to the writer for the entire time that the disc is being written. no interruptions allowed, bestie, the buffer stays FED πŸ’€

🐚 Dealing with path names 🐚

pathspec is the path of the directory tree to be copied into the ISO-9660 filesystem. multiple paths can be specified, and mkisofs will merge the files found in all of the specified path components to form the cdrom image. group project but make it functional 🫢

if the option -graft-points has been specified, it is possible to graft the paths at points other than the root directory, and it is possible to graft files or directories onto the cdrom image with names different than what they have in the source filesystem. this is easiest to illustrate with a couple of examples. let's start by assuming that a local file ../old.lis exists, and you wish to include it in the cdrom image.

foo/bar/=../old.lis

will include the file old.lis in the cdrom image at /foo/bar/old.lis, while

foo/bar/xxx=../old.lis

will include the file old.lis in the cdrom image at /foo/bar/xxx. the same sort of syntax can be used with directories as well. mkisofs will create any directories required such that the graft points exist on the cdrom image β€” the directories do not need to appear in one of the paths. by default, any directories that are created on the fly like this will have permissions 0555 and appear to be owned by the person running mkisofs. if you wish other permissions or owners of the intermediate directories, see -uid, -gid, -dir-mode, -file-mode and -new-dir-mode. iconic customization options tbh πŸ‘‘

mkisofs will also run on Win9x/NTx machines when compiled with Cygnus' cygwin (available from http://sourceware.cygnus.com/cygwin/). therefore most references in this man page to Unix also apply to Win32 or Win64. it's inclusive like that 🌈


πŸ’… OPTIONS πŸ’…

  • -abstract FILE β€” specifies the abstract file name in the primary volume descriptor. there is space on the disc for 37 characters of information. the related Joliet entry is limited to 18 characters. this parameter can also be set in the file .mkisofsrc with ABST=filename. if specified in both places, the command line version is used.

it is up to the user of mkisofs to include a file with the apropriate name in the created filesystem tree. yes, you, bestie, that part is on you πŸ™ˆ

  • -A application_id
  • -appid application_id β€” specifies a text string that will be written into the volume header. this should describe the application that will be on the disc. there is space on the disc for 128 characters of information. the related Joliet entry is limited to 64 characters. this parameter can also be set in the file .mkisofsrc with APPI=id. if specified in both places, the command line version is used. put your whole brand on it ✨
  • -allow-leading-dots
  • -ldots β€” allow ISO-9660 filenames to begin with a period. usually, a leading dot is replaced with an underscore in order to maintain MS-DOS compatibility. this violates the ISO-9660 standard, but it happens to work on many systems. use with caution. ⚠️
  • -allow-lowercase β€” this options allows lower case characters to appear in ISO-9660 filenames. this violates the ISO-9660 standard, but it happens to work on some systems. use with caution. ⚠️
  • -no-allow-lowercase β€” this resets the effect of -allow-lowercase and even works when -U, -untranslated-filenames or -iso-level 4 have been used to allow lowercase filenames. takebacks are valid πŸ’…
  • -allow-multidot β€” this options allows more than one dot to appear in ISO-9660 filenames. a leading dot is not affected by this option, it may be allowed separately using the -allow-leading-dots option. this violates the ISO-9660 standard, but it happens to work on many systems. use with caution. ⚠️ dots for days fr fr
  • -biblio FILE β€” specifies the bibliographic file name in the primary volume descriptor. there is space on the disc for 37 characters of information. the related Joliet entry is limited to 18 characters. this parameter can also be set in the file .mkisofsrc with BIBLO=filename. if specified in both places, the command line version is used.

it is up to the user of mkisofs to include a file with the apropriate name in the created filesystem tree. again: your job, bestie 🫢

  • -cache-inodes β€” cache inode and device numbers to find hard links to files. if mkisofs finds a hard link (a file with multiple names), then the file will only appear once on the CD. this helps to save space on the CD. the option -cache-inodes is default on UNIX like operating systems. be careful when using this option on a filesystem without unique inode numbers as it may result in files containing the wrong content on CD. πŸ’€

see the option -duplicates-once for a method that works on filesystems without unique inode numbers.

if inodes are not cached, mkisofs will revert to the old Rrip Version-1.10 (see -rrip110) and mkisofs will not be able to create correct inode numbers for zero sized files.

  • -no-cache-inodes β€” do not cache inode and device numbers. this option is needed whenever a filesystem does not have unique inode numbers. it is the default on old Cygwin versions. as the Microsoft operating system that runs below Cygwin uses 64 bit inode numbers for NTFS, it does not have unique inode numbers in the 32 bit range. old Cygwin versions create fake 32-bit inode numbers from a hash algorithm and thus create non-unique numbers. if mkisofs would cache inodes on old Cygwin versions, it would believe that some files are identical although they are not. the result in this case are files that contain the wrong content if a significant amount of different files (> ~5000) is in inside the tree that is to be archived. this does not happen when the -no-cache-inodes is used, but the disadvantage is that mkisofs cannot detect hardlinks anymore and the resulting CD image may be larger than expected. 😭

if inodes are not cached, mkisofs will revert to the old Rrip Version-1.10 (see -rrip110) and mkisofs will not be able to create correct inode numbers for zero sized files.

  • -duplicates-once β€” tells mkisofs to use a message digest checksum to sniff out identical files that look like hard links πŸ•΅οΈβ€β™€οΈ. this is the moment where you can archive inode numbers and hard links even when you're running on non-POSIX platforms like DOS. iconic, honestly.
  • -b eltorito_boot_image, -eltorito-boot eltorito_boot_image β€” says which image file becomes the boot image when you're making an El Torito bootable CD πŸ’Ώβœ¨. the pathname has to be relative to the source path and live inside the source tree you handed to mkisofs. this option is required to make an El Torito bootable CD, no cap. the boot image must be exactly the size of either a 1200, 1440, or a 2880 kB floppy, and mkisofs will use this size when creating the output ISO-9660 filesystem. it's assumed the first 512 byte sector should be read from the boot image (it's basically emulating a normal floppy drive). this will work, for example, if the boot image is a boot floppy 🫢.

if the boot image is not an image of a floppy, you need to add one of the options: -hard-disk-boot or -no-emul-boot. and if the system should not boot off the emulated disk, use -no-boot.

more than one boot entry may be specified β€” see -eltorito-platform and -eltorito-alt-boot for how to specify more boot entries πŸ‘€. the first boot entry is the default boot entry. additional boot entries are members for a multi boot configuration.

if the -sort option has not been specified, the boot images get sorted with low priority (+2) to the beginning of the medium. if you don't like that, you need to specify a sort weight of 0 for the boot images πŸ’….

  • -eltorito-alt-boot β€” start with a fresh new set of El Torito boot parameters πŸ”„. this is how you get more than one El Torito boot entry on a CD β€” a maximum of 63 El Torito boot entries may be put on a single CD, bestie, so pace yourself.

the -eltorito-alt-boot option starts a new boot entry with the same platform id but no new boot section, except when it appears past the first boot entry which is the default boot entry.

  • -eltorito-platform id β€” sets the El Torito platform id for a boot record or a section of boot records πŸŽ€. the id parameter may be either:
    • x86 β€” this is the default platform id value and specifies entries for the PC platform. if no -eltorito-platform option appears before the first -eltorito-boot option, the default boot entry becomes an entry for the x86 PC platform.
    • PPC β€” boot entries for the Power PC platform.
    • Mac β€” boot entries for the Apple Mac platform.
    • efi β€” boot entries for EFI based PCs.
    • # β€” a numeric value specifying any platform id.

if the option -eltorito-platform appears before the first -eltorito-boot option, it sets the platform id for the default boot entry.

if the option -eltorito-platform appears after an -eltorito-boot option and sets the platform id to a value different from the previous value, it starts a new set of boot entries πŸ”₯.

the second boot entry and any new platform id creates a new section header and reduces the number of boot entries per CD by one.

  • errctl= name, errctl= error control spec β€” add the content from file name to the error control definitions, or add error control spec to the error control definitions πŸ™ˆ. more than one error control file and more than one error control spec, as well as a mixture of both forms, is possible.

the reason for using error control is to make mkisofs quiet about error conditions that are known to be irrelevant on the quality of the created filesystem, or to tell mkisofs to abort on certain error conditions instead of trying to continue with the filesystem.

a typical reason to use error control is to suppress warnings about growing log files while doing a backup on a live file system. another typical reason is to tell mkisofs to abort if, e.g., a file could not be archived, instead of continuing to archive other files from a list 🫑.

the error control file contains a set of lines, each starting with a list of error conditions to be ignored, followed by white space, followed by a file name pattern (see match(1) or patmatch(3) for more information). the error control spec uses the same syntax as a single line from the error control file. if the file name pattern needs to start with white space, use a backslash to escape the start of the file name. it is not possible to have new line characters in the file name pattern. whenever an error situation is encountered, mkisofs checks the lines in the error control file starting from the top. if the current error condition is listed on a line in the error control file, then mkisofs checks whether the pattern on the rest of the line matches the current file name. if this is the case, mkisofs uses the current error control specification to control the current error condition ✨.

the list of error conditions to be handled may use one or more (in this case separated by a '|' character) identifiers from the list below:

  • ABORT β€” if this meta condition is included in an error condition, mkisofs aborts (exits) as soon as possible after this error condition has been seen, instead of making mkisofs quiet about the condition. this error condition flag may only be used together with at another error condition or a list of error conditions (separated by a '|' character).
  • WARN β€” if this meta condition is included in an error condition, mkisofs prints the warning about the error condition, but the error condition does not affect the exit code of mkisofs, and the error statistics (which is printed to the end) does not include the related errors. this error condition flag may only be used together with at another error condition or a list of error conditions (separated by a '|' character). the WARN meta condition has a lower precedence than ABORT.
  • ALL β€” this is a shortcut for all error conditions below πŸ’«.
  • STAT β€” suppress warnings that mkisofs could not stat(2) a file.
  • GETACL β€” suppress warnings about files on which mkisofs had problems to retrieve the ACL information.
  • OPEN β€” suppress warnings about files that could not be opened.
  • READ β€” suppress warnings read errors on files.
  • WRITE β€” suppress warnings write errors on files.
  • READLINK β€” suppress warnings readlink(2) errors on symbolic links.
  • GROW β€” suppress warnings about files that did grow while they have been archived.
  • SHRINK β€” suppress warnings about files that did shrink while they have been archived.
  • MISSLINK β€” suppress warnings about files for which mkisofs was unable to archive all hard links.
  • NAMETOOLONG β€” suppress warnings about files that could not be archived because the name of the file is too long for the archive format.
  • FILETOOBIG β€” suppress warnings about files that could not be archived because the size of the file is too big for the archive format.
  • SPECIALFILE β€” suppress warnings about files that could not be archived because the file type is not supported by the archive format.
  • GETXATTR β€” suppress warnings about files on that mkisofs could not retrieve the extended file attribute information.
  • SETTIME β€” suppress warnings about files on that mkisofs could not set the time information during extraction.
  • SETMODE β€” suppress warnings about files on that mkisofs could not set the access modes during extraction.
  • SECURITY β€” suppress warnings about files that have been skipped on extraction because they have been considered to be a security risk. this currently applies to all files that have a '/../' sequence inside when -.. has not been specified.
  • LSECURITY β€” suppress warnings about links that have been skipped on extraction because they have been considered to be a security risk. this currently applies to all link names that start with '/' or have a '/../' sequence inside when -secure-links has been specified. in this case, mkisofs tries to match the link name against the pattern in the error control file.
  • SAMEFILE β€” suppress warnings about links that have been skipped on extraction because source and target of the link are pointing to the same file. if mkisofs would not skip these files, it would end up with removing the file completely 😭. in this case, mkisofs tries to match the link name against the pattern in the error control file.
  • BADACL β€” suppress warnings access control list conversion problems.
  • SETACL β€” suppress warnings about files on that mkisofs could not set the ACL information during extraction.
  • SETXATTR β€” suppress warnings about files on that mkisofs could not set the extended file attribute information during extraction.

if a specific error condition is ignored, then the error condition is not only handled in a silent way but also excluded from the error statistics that are printed at the end of the mkisofs run.

πŸ’€ be very careful when using error control as you may ignore any error condition. if you ignore the wrong error conditions, you may not be able to see real problems anymore. like, don't mute the smoke alarm, bestie.
πŸ¦‹ note that currently only the tags OPEN, READ, GROW, SHRINK, are checked from mkisofs. iykyk.
  • -B img_sun4,img_sun4c,img_sun4m,img_sun4d,img_sun4e
  • -sparc-boot img_sun4,img_sun4c,img_sun4m,img_sun4d,img_sun4e β€” ok so this one gives you a comma separated list of boot images you need to build a bootable CD for sparc systems πŸ¦‹ Partition 0 is reserved for the ISO-9660 image, and the first image file gets mapped to partition 1. You can absolutely leave empty fields in that comma separated list, no biggie. Max possible partitions is 8, so it is literally impossible to specify more than 7 partition images β€” math is math πŸ’… This option is required to make a bootable CD for Sun sparc systems. And if -B or -sparc-boot has been specified, the first sector of the resulting image will contain a Sun disk label. That disk label specifies slice 0 for the ISO-9660 image and slice 1 … slice 7 for the boot images you specified with this option. Byte offset 512 … 8191 within each of the additional boot images must contain a primary boot that works for the appropriate sparc architecture. The rest of each of those images usually contains a ufs filesystem that's used as the primary kernel boot stage.

The implemented boot method is the boot method found with SunOS 4.x and SunOS 5.x. But plot twist: it does not depend on SunOS internals, only on properties of the Open Boot prom ✨ For this reason it should be usable for any OS that boots off a sparc system. Iconic behaviour honestly.

For more info also see the NOTES section below.

If the special filename ... is used, the actual and all following boot partitions are mapped to the previous partition. So if mkisofs is called with -G image -B ... all boot partitions are mapped to the partition that contains the ISO-9660 filesystem image, and the generic boot image that sits in the first 16 sectors of the disk is used for all architectures πŸ‘‘

  • -G generic_boot_image β€” specifies the path and filename of the generic boot image to use when making a generic bootable CD πŸŽ€ The generic_boot_image gets placed on the first 16 sectors of the CD. And those first 16 sectors are the sectors located before the ISO-9660 primary volume descriptor, jsyk. If you use this together with the -sparc-boot option, the Sun disk label will overlay the first 512 bytes of the generic boot image. Layers, bestie πŸ’…
  • -hard-disk-boot β€” says the boot image used to create "El Torito" bootable CDs is a hard disk image 🫢 That hard disk image must begin with a master boot record that contains a single partition. No notes.
  • -ignore-error β€” ignores errors 😭 mkisofs by default aborts on several errors, like read errors. With this option in effect, mkisofs tries to continue instead. Use with care, fr fr.
  • -no-emul-boot β€” says the boot image used to create "El Torito" bootable CDs is a 'no emulation' image πŸ’– The system will load and execute this image without performing any disk emulation. Zero emulation, all vibes.
  • -no-boot β€” says the created "El Torito" CD should be marked as not bootable πŸ™ˆ The system will still provide an emulated drive for the image, but will boot off a standard boot device.
  • -boot-load-seg segment_address β€” specifies the load segment address of the boot image for no-emulation "El Torito" CDs ⭐
  • -boot-load-size load_sectors β€” specifies the number of "virtual" (512-byte) sectors to load in no-emulation mode 🌸 The default is to load the entire boot file. Heads up: some BIOSes may have problems if this is not a multiple of 4. Do with that what you will.
  • -boot-info-table β€” specifies that a 56-byte table with information of the CD-ROM layout will be patched in at offset 8 in the boot file πŸ¦‹ See the EL TORITO BOOT INFO TABLE section for a description of this table.
⚠️ If this option is given, the boot file is modified in the source filesystem, so make sure to make a copy if this file cannot be easily regenerated! Like, actually. Save a copy first 😭
  • -C last_sess_start,next_sess_start
  • -cdrecord-params last_sess_start,next_sess_start β€” this option is needed when mkisofs is used to create a CDextra, or the image of a second session, or a higher level session for a multi session disk πŸ’Ώ The option -C takes a pair of two numbers separated by a comma. First number = the sector number of the first sector in the last session of the disk that should be appended to. Second number = the starting sector number of the new session. The expected pair of numbers may be retrieved by calling cdrecord -msinfo ...

If -C is used in conjunction with the -M option, mkisofs creates a filesystem image that's intended to be a continuation of the previous session ✨ If -C is used without -M, mkisofs creates a filesystem image intended to be used for a second session on a CDextra β€” that's a multi session CD holding audio data in the first session and an ISO-9660 filesystem in the second session. Cute combo tbh.

  • -c boot_catalog
  • -eltorito-catalog boot_catalog β€” specifies the path and filename of the boot catalog used when making an "El Torito" bootable CD πŸŽ€ The pathname must be relative to the source path specified to mkisofs. This option is required to make a bootable CD. This file gets inserted into the output tree and is not created in the source filesystem, so be sure the specified filename does not conflict with an existing file, because it will be excluded πŸ’… Usually a name like boot.catalog is chosen.

If the -sort option has not been specified, the boot catalog is sorted with low priority (+1) to the beginning of the medium. If you don't like this, you need to specify a sort weight of 0 for the boot catalog.

  • -check-oldnames β€” checks all filenames imported from the old session for compliance with the actual mkisofs ISO-9660 file naming rules πŸ” If this option is not present, only names with a length > 31 are checked, since those files are a hard violation of the ISO-9660 standard.
  • -check-session FILE β€” checks all old sessions for compliance with actual mkisofs ISO-9660 file naming rules 🌈 This is a high level option that's a combination of the options: -M FILE -C 0,0 -check-oldnames β€” for the parameter FILE see the description of the -M option πŸ‘‘
  • -copyright FILE β€” specifies the Copyright file name in the primary volume descriptor πŸ“œ There's space on the disc for 37 characters of information. The related Joliet entry is limited to 18 characters. This parameter can also be set in the file .mkisofsrc with COPY=filename. If specified in both places, the command line version wins. And it's up to the user of mkisofs to include a file with the appropriate name in the created filesystem tree β€” that part's on you, bestie πŸ’–
  • -d
  • -omit-period β€” omits the trailing period from files that do not have a period 🌸
⚠️ This violates the ISO-9660 standard, but it happens to work on many systems. Use with caution.
  • -D
  • -disable-deep-relocation β€” do not use Rock Ridge deep directory relocation; instead just pack directories the way they are in the master directory tree πŸ¦‹

This option was needed with old mkisofs versions to avoid a visible directory rr_moved. Since August 2006, mkisofs correctly hides the rr_moved directory from the Rock Ridge filesystem β€” so, glow up ✨

If ISO-9660:1999 has not been selected, this violates the ISO-9660 standard, but it happens to work on many systems. Use with caution πŸ’…

  • -data-change-warn β€” if the size of a file changes while the file is being archived, treat this condition as a warning only that does not cause mkisofs to abort 😌 A warning message is still written if the condition isn't otherwise ignored by another rule from an errctl= option. The -data-change-warn option works as if the last error control option was
     errctl="WARN|GROW|SHRINK *"
  • -debug β€” increments the debug value by one πŸ› That's it. That's the option.
  • -dir-mode mode β€” overrides the mode of directories used to create the image to mode πŸŽ€ See -new-dir-mode on how to specify a different mode that's used for directories that do not exist in the tree specified by the source-path. Specifying the -dir-mode option automatically enables Rock Ridge extensions.
  • -dvd-audio β€” generates a DVD-Audio compliant UDF file system πŸ’Ώ This is done by sorting the order of the content of the appropriate files. Sorting only works if the DVD-Audio filenames include upper case characters only, so, caps lock era.

Note that in order to get a DVD-Audio compliant filesystem image, you need to prepare a DVD-Audio compliant directory tree 🫢 Which means you need a directory AUDIO_TS (all caps) in the root directory of the resulting DVD, and you should have a directory VIDEO_TS. The AUDIO_TS directory needs to include all needed files (file names must be all caps) for a compliant DVD-Audio filesystem.

  • -dvd-hybrid β€” equivalent to selecting both -dvd-audio and -dvd-video ✨ Two for the price of one, we love efficiency.
  • -dvd-video β€” generates a DVD-Video compliant UDF file system 🎬 This is done by sorting the order of the content of the appropriate files and by adding padding between the files if needed. Sorting only works if the DVD-Video filenames include upper case characters only.

Note that in order to get a DVD-Video compliant filesystem image, you need to prepare a DVD-Video compliant directory tree πŸ’– Which means you need a directory VIDEO_TS (all caps) in the root directory of the resulting DVD, and you should have a directory AUDIO_TS. The VIDEO_TS directory needs to include all needed files (file names must be all caps) for a compliant DVD-Video filesystem.

  • -f
  • -follow-links β€” follows all symbolic links when generating the filesystem πŸ”— When this option is not in use, symbolic links will be entered using Rock Ridge if enabled β€” otherwise the file will be ignored. See also the -posix-L option.
  • -file-mode mode β€” overrides the mode of regular files used to create the image to mode 🌟 Specifying this option automatically enables Rock Ridge extensions.
  • -find β€” this option acts as a separator πŸ›‘ If it's used, all mkisofs options must be to the left of the -find option. To the right of the -find option, mkisofs accepts the find command line syntax only. Like a little border checkpoint, no cap.

The find expression is basically a little bouncer standing between where the filenames come from and the consumer (which is the archiving engine, aka the one actually doing the work πŸ’…). If the find expression evaluates as TRUE, the file in question gets picked for processing. If not? Omitted. Bye. Not invited. πŸ™ˆ

And to make evaluating the find expression more convenient, mkisofs implements extra find primaries that have side effects on the file meta data. Obsessed tbh. Here's the full lineup of what mkisofs adds:

  • -help β€” lists the available find(1) syntax. Little cheat sheet moment ✨
  • -chgrp gname β€” this primary always evaluates as true; it sets the group of the file to gname.
  • -chmod mode β€” this primary always evaluates as true; it sets the permissions of the file to mode. Octal and symbolic permissions are both accepted for mode, just like with chmod(1).
  • -chown uname β€” this primary always evaluates as true; it sets the owner of the file to uname.
  • -false β€” this primary always evaluates as false; it lets you make the result of the full expression different from the result of a part of the expression.
  • -true β€” this primary always evaluates as true; it lets you make the result of the full expression different from the result of a part of the expression.

Okay now the fun part, examples πŸŽ€ The command line:

mkisofs -o o.iso -find . ( -type d -ls -o false ) -o ! -type d

lists all directories and puts all non-directories into the image o.iso. She's dividing the room, bestie.

And this command line:

mkisofs -o o.iso -find . ( -type d -chown root -o true )

archives all directories so they appear to be owned by root in the archive, while all non-directories get archived exactly as they are in the file system. Iconic behaviour honestly πŸ‘‘

Heads up fr fr: the -ls, -exec and the -ok primary cannot be used if stdin or stdout has not been redirected. Not negotiable, that's just how it is 😭

  • -gid gid β€” overrides the gid read from the source files to the value of gid. Specifying this option automatically enables Rock Ridge extensions. Two birds, one stone πŸ¦‹
  • -gui β€” switches the behaviour for a GUI. Currently this just makes the output more verbose, but it may have other effects in future. Main character option with future plans ngl.
  • -graft-points β€” allows you to use graft points for filenames. If this option is used, all filenames get checked for graft points. The filename is divided at the first unescaped equal sign. All occurrences of '\\' and '=' characters must be escaped with '\\' if -graft-points has been specified. Escape your stuff or things get weird πŸ’…
  • -hide glob β€” hides glob from being seen on the ISO-9660 or Rock Ridge directory. glob is a shell wild-card-style pattern that must match any part of the filename or path. Multiple globs may be hidden. If glob matches a directory, then the contents of that directory will be hidden. In order to match a directory name, make sure the pathname does not include a trailing '/' character. All the hidden files will still be written to the output CD image file. Should be used with the -hide-joliet option. See README.hide for more details. Sneaky but the data is still in there πŸ‘€
  • -hide-list file β€” a file containing a list of globs to be hidden, as above. Bulk hiding, we love efficiency.
  • -hidden glob β€” adds the hidden (existence) ISO-9660 directory attribute for glob. This attribute will prevent glob from being listed on DOS based systems if the /A flag is not used for the listing. glob is a shell wild-card-style pattern that must match any part of the filename or path. In order to match a directory name, make sure the pathname does not include a trailing '/' character. Multiple globs may be hidden. Lowkey invisible mode ✨
  • -hidden-list file β€” a file containing a list of globs to get the hidden attribute, as above.
  • -hide-joliet glob β€” hides glob from being seen on the Joliet directory. glob is a shell wild-card-style pattern that must match any part of the filename or path. Multiple globs may be hidden. If glob matches a directory, then the contents of that directory will be hidden. In order to match a directory name, make sure the pathname does not include a trailing '/' character. All the hidden files will still be written to the output CD image file. Should be used with the -hide option. See README.hide for more details.
  • -hide-joliet-list file β€” a file containing a list of globs to be hidden, as above.
  • -hide-joliet-trans-tbl β€” hides the TRANS.TBL files from the Joliet tree. These files usually don't make sense in the Joliet World, since they list the real name and the ISO-9660 name β€” and both of those may be different from the Joliet name. It's giving redundant, so hide it 🫢
  • -hide-rr-moved β€” renames the directory RR_MOVED to .rr_moved in the Rock Ridge tree. This option was introduced back when mkisofs wasn't able to hide the directory in the Rock Ridge tree. This version of mkisofs always automatically hides the RR_MOVED directory in the Rock Ridge tree. If you need to have no RR_MOVED directory at all (even in the ISO-9660 tree), you should use the -D option. Note that in the case that the -D option has been specified, the resulting filesystem is not ISO-9660 level-1 compliant and will not be readable on MS-DOS. See also the NOTES section for more information on the RR_MOVED directory.
Okay so that last one matters: -D = no RR_MOVED directory at all, but the filesystem stops being ISO-9660 level-1 compliant and MS-DOS won't read it. Choose your fighter 😭
  • -hide-udf glob β€” hides glob from being seen on the UDF directory. glob is a shell wild-card-style pattern that must match any part of the filename or path. Multiple globs may be hidden. If glob matches a directory, then the contents of that directory will be hidden. In order to match a directory name, make sure the pathname does not include a trailing '/' character. All the hidden files will still be written to the output CD image file. Should be used with the -hide option. See README.hide for more details.
  • -hide-udf-list file β€” a file containing a list of globs to be hidden, as above.
  • -hide-ignorecase
  • -exclude-ignorecase β€” ignore the case of the filenames with the -hide* options and with the -exclude-list option. Case sensitivity? Never heard of her πŸŽ€
  • -input-charset charset β€” sets up the input charset that defines the characters used in local file names. To get a list of valid charset names, call mkisofs -input-charset help. To get a 1:1 mapping, you may use default as the charset name. If the input charset has not been set up from the locale in the environment, the default initial values are cp437 on DOS based systems and iso8859-1 on all other systems. See the CHARACTER SETS section below for more details.

If -input-charset has not been specified, it will be set up from the locale in the environment. If you'd like to disable this automatic setup, use the empty string as the locale name. Opting out is valid πŸ’…

  • -output-charset charset β€” sets up the output charset that defines the characters that will be used in Rock Ridge file names. Defaults to the input charset. See the CHARACTER SETS section below for more details.
  • -iso-level level β€” sets the ISO-9660 conformance level. Valid numbers are 1..3 and 4. Let's break it down, bestie:
    • With level 1, files may only consist of one section and filenames are restricted to 8.3 characters.
    • With level 2, files may only consist of one section.
    • With level 3, no restrictions (other than ISO-9660:1988) apply. Starting with this level, mkisofs also allows files to be larger than 4 GB by implementing ISO-9660 multi-extent files. Big file energy πŸ”₯
    • With all ISO-9660 levels from 1..3, all filenames are restricted to upper case letters, numbers and the underscore (_). The maximum filename length is restricted to 31 characters, the directory nesting level is restricted to 8 and the maximum path length is limited to 255 characters.
    • Level 4 officially does not exist, but mkisofs maps it to ISO-9660:1999, which is ISO-9660 version 2.
    • With level 4, an enhanced volume descriptor with version number and file structure version number set to 2 is emitted. There may be more than 8 levels of directory nesting, there is no need for a file to contain a dot and the dot has no more special meaning, file names do not have version numbers, the maximum length for files and directory is raised to 207. If Rock Ridge is used, the maximum ISO-9660 name length is reduced to 197.

When creating Version 2 images, mkisofs emits an enhanced volume descriptor which looks similar to a primary volume descriptor but is slightly different.

⚠️ Be careful not to use broken software to make ISO-9660 images bootable by assuming a second PVD copy and patching this putative PVD copy into an El Torito VD. That's the whole warning, no cap. Do not do it πŸ’€
  • -J β€” generates Joliet directory records in addition to regular ISO-9660 file names. This is primarily useful when the discs are to be used on Windows-NT or Windows-95 machines. The Joliet filenames are specified in Unicode and each path component can be up to 64 Unicode characters long. Note that Joliet is no standard β€” CD's that use only Joliet extensions but no standard Rock Ridge extensions may usually only be used on Microsoft Win32 systems. Furthermore, the fact that the filenames are limited to 64 characters and the fact that Joliet uses the UTF-16 coding for Unicode characters causes interoperability problems. It's giving convenience-with-strings-attached 😬
  • -joliet-long β€” allows Joliet filenames to be up to 103 Unicode characters. This breaks the Joliet specification β€” but appears to work. Use with caution. The number 103 is derived from: the maximum Directory Record Length (254), minus the length of Directory Record (33), minus CD-ROM XA System Use Extension Information (14), divided by the UTF-16 character size (2). Math slay, honestly 🧚
  • -jcharset charset β€” same as using -input-charset charset and -J options. See the CHARACTER SETS section below for more details.
  • -l
  • -full-iso9660-filenames β€” allows full 31 character filenames. Normally the ISO-9660 filename will be in an 8.3 format, which is compatible with MS-DOS, even though the ISO-9660 standard allows filenames of up to 31 characters. If you use this option, the disc may be difficult to use on a MS-DOS system, but this comes in handy on some other systems (such as the Amiga). Use with caution.
Yeah that's a caution twice in a row. The universe is telling you something 🌸
  • -L β€” ok so this one is outdated and reserved by POSIX.1-2001 🫠 use -allow-leading-dots instead, bestie. It'll get POSIX.1-2001 semantics with mkisofs-3.02.
  • -log-file log_file β€” redirects all your error, warning, and informational messages into log_file instead of standard error. very "keep receipts" of you πŸ“
  • -long-rr-time β€” uses the long ISO-9660 time format for the file time stamps in Rock Ridge. This one lets you represent year 0 .. year 9999 with a granularity of 10ms. iconic range honestly ✨

For contrast: the short ISO-9660 time format only lets you represent year 1900 .. year 2155 with a granularity of 1s. so yeah, -long-rr-time is the main character here πŸ‘‘

  • -m glob β€” excludes glob from being written to the CDROM. glob is a shell wildcard-style pattern that has to match part of the filename (not the path, the way -x does it). Technically, glob gets matched against the d->d_name part of the directory entry. You can exclude multiple globs. Example time:
mkisofs -o rom -m '*.o' -m core -m foobar

That would exclude all files ending in ".o", plus anything called "core" or "foobar", from being copied to the CDROM. Heads up tho: if you had a directory called "foobar", it too (and of course all its descendants) would be excluded. πŸ’€

NOTE: the -m and -x option descriptions should both be updated, they're wrong. Both now work identical and use filename globbing. A file is excluded if either the last component matches or the whole path matches.
  • -exclude-list file β€” a file containing a list of globs to be excluded, same deal as above πŸŽ€
  • -max-iso9660-filenames β€” allows 37 chars in ISO-9660 filenames. This option forces the -N option, because the extra name space is taken from the space reserved for ISO-9660 version numbers. It violates the ISO-9660 standard, but it happens to work on many systems. Although a conforming application needs to provide a buffer space of at least 37 characters, disks created with this option may cause a buffer overflow in the reading operating system. Use with extreme care 😭πŸ”₯ (like, fr fr, be careful.)
  • -M path

or

-M device

or

-dev device β€” specifies the path to an existing ISO-9660 image to be merged. The alternate form takes a SCSI device specifier that uses the same syntax as the dev= parameter of cdrecord. The output of mkisofs will be a new session which should get written to the end of the image specified in -M. Typically this requires multi-session capability for the recorder and cdrom drive that you're attempting to write this image to. This option may only be used in conjunction with the -C option. 🫢

  • -modification-date date-spec β€” sets the modification date in the primary volume descriptor (PVD) to a value different from the current time. This lets you, like, set up an intentional UUID for grub πŸ‘€

The format of date-spec is:

yyyy[mm[dd[hh[mm[ss]]]]][.hh][+-ghgm]

The fields are year, month, day of month, hour, minute, second, hundreds of a second, GMT offset in hours and minutes. The time is interpreted as local time. ⏰

Year and the GMT offset are four digit fields; all other fields take two digits. The GMT offset may be between -12 and +13 hours in 15 minute steps. Locations east of Greenwich have positive values. The value is the sum of the time zone offset and the effects from daylight saving time. Omitted values are replaced by the minimal possible values. If the GMT offset is omitted, it's computed from the local time value that has been supplied. 🧚

Between year and month as well as between month and day of month, a separator chosen from '/' and '-' may appear. In this case, the year may be a two digit number with values 69..99 representing 1969..1999 and values 00..68 representing 2000..2068. Between date and time spec, an optional space is permitted. Between hours and minutes as well as between minutes and seconds, an optional ':' separator is permitted. This all lets mkisofs parse the popular POSIX date format created by:

date "+%Y-%m-%d %H:%M:%S %z"
Note that the possible range for date-spec for 32 bit programs is limited to values up to 2038 Jan 19 04:14:07 GMT. y2k38 said hi πŸ™ˆ
  • -N

-omit-version-number β€” omits version numbers from ISO-9660 file names. This violates the ISO-9660 standard, but no one really uses the version numbers anyway. Use with caution 🌸

  • -new-dir-mode mode β€” the mode to use when creating new directories in the iso fs image. The default mode in the absence of a -dir-mode option is 0555. πŸŽ€
  • -nobak

-no-bak β€” do not include backup files on the ISO-9660 filesystem. If the -no-bak option is specified, files that contain the characters '~' or '#' or end in '.bak' will not be included (these are typically backup files for editors under UNIX). slay, no more editor clutter πŸ’…

  • -no-limit-pathtables β€” an ISO-9660 filesystem contains path tables that contain a list of directories. This list may contain many directories but only 65535 of them may be parent directories. When -no-limit-pathtables is in use, further parent directories will be folded to the root directory, and the resulting filesystem will no longer be usable on DOS. 🫠
  • -no-long-rr-time β€” uses the short ISO-9660 time format for the file time stamps used in Rock Ridge. This time format lets you represent year 1990 .. year 2155 with a granularity of one second. lowkey the humble option 🌈
  • -force-rr β€” do not use the automatic Rock Ridge attributes recognition for previous sessions. This helps to show rotten ISO-9660 extension records as e.g. created by NERO burning ROM. πŸ’€
  • -no-rr β€” do not use the Rock Ridge attributes from previous sessions. This may help to avoid getting into trouble when mkisofs finds illegal Rock Ridge signatures on an old session. πŸ™ˆ
  • -no-split-symlink-components β€” don't split the SL components, but begin a new Continuation Area (CE) instead. This may waste some space, but the SunOS 4.1.4 cdrom driver has a bug in reading split SL components (link_size = component_size instead of link_size += component_size). 😭
Note that this option has been introduced by Eric Youngdale in 1997. It is questionable whether it makes sense at all. When it was introduced, mkisofs did have a serious bug that did create defective CE signatures if a symlink contained `/../`. This CE signature bug in mkisofs has been fixed in May 2003.
  • -no-split-symlink-fields β€” don't split the SL fields, but begin a new Continuation Area (CE) instead. This may waste some space, but the SunOS 4.1.4 and Solaris 2.5.1 cdrom driver have a bug in reading split SL fields (a '/' can be dropped). 😭
Note that this option has been introduced by Eric Youngdale in 1997. It is questionable whether it makes sense at all. When it was introduced, mkisofs did have a serious bug that did create defective CE signatures if a symlink contained `/../`. This CE signature bug in mkisofs has been fixed in May 2003. (yes, same lore, different driver bugs 🫢)
  • -o filename β€” the name of the file to which the ISO-9660 filesystem image should be written. This can be a disk file, a tape drive, or it can correspond directly to the device name of the optical disc writer. If not specified, stdout is used. Note that the output can also be a block special device for a regular disk drive, in which case the disk partition can be mounted and examined to ensure that the premastering was done correctly. ⭐
  • -pad β€” pads the end of the whole image by 150 sectors (300 kB). If the -B option is used, then there's a padding at the end of the ISO-9660 partition and before the beginning of the boot partitions. The size of this padding is chosen to make the first boot partition start on a sector number that is a multiple of 16.

The padding is needed because many operating systems (e.g. Linux) implement read ahead bugs in their filesystem I/O. These bugs result in read errors on one or more files that are located at the end of a track. They're usually present when the CD is written in Track at Once mode or when the disk is written as mixed mode CD where an audio track follows the data track. 😀

To avoid problems with I/O error on the last file on the filesystem, the -pad option has been made the default. she's the blueprint πŸ’…

  • -no-pad β€” do not pad the end by 150 sectors (300 kB) and do not make the boot partitions start on a multiple of 16 sectors. go off then, risk it 🫠
  • -path-list file β€” a file containing a list of pathspec directories and filenames to be added to the ISO-9660 filesystem. This list of pathspecs is processed after any that appear on the command line. If the argument is -, then the list is read from the standard input. πŸŽ€
  • -P β€” another outdated option reserved by POSIX.1-2001; use -publisher instead. This option will get POSIX.1-2001 semantics with mkisofs-3.02.
  • -publisher publisher_id β€” specifies a text string that will be written into the volume header. This should describe the publisher of the CDROM, usually with a mailing address and phone number. There's space on the disc for 128 characters of information. The related Joliet entry is limited to 64 characters. This parameter can also be set in the file .mkisofsrc with PUBL=. If specified in both places, the command line version is used. πŸ‘‘
  • -p preparer_id

-preparer preparer_id β€” specifies a text string that will be written into the volume header. This should describe the preparer of the CDROM, usually with a mailing address and phone number. There's space on the disc for 128 characters of information. The related Joliet entry is limited to 64 characters. This parameter can also be set in the file .mkisofsrc with PREP=. If specified in both places, the command line version is used. 🫢

  • -posix-H β€” follows all symbolic links encountered on the command line when generating the filesystem. πŸ¦‹
  • -posix-L β€” follows all symbolic links when generating the filesystem. When this option is not in use, symbolic links will be entered using Rock Ridge if enabled, otherwise the file will be ignored. ✨
  • -posix-P β€” bestie, do not follow symbolic links when generating the filesystem (this is the default btw). And if you slap -posix-P after -posix-H or -posix-L, it literally resets whatever those did. Order matters, iykyk πŸ’…
  • -print-size β€” prints the estimated filesystem size in multiples of the sector size (2048 bytes) and then dips ✌️. This one's needed for Disk At Once mode and for some CD-R drives when you're piping directly into cdrecord. Basically you gotta know how big the filesystem is before the actual CD-creation happens, and -print-size lets you get that number from a "dry-run" before anything gets written. Old versions of mkisofs wrote this info (plus other stuff) to stderr, but that turned out to be a nightmare to parse, so now the number gets printed on stdout too, all by itself, no extra noise. If you wanna write a simple shell script, redirect stderr and catch the number from stdout πŸŽ€. Like this:
cdblocks=` mkisofs -print-size -quiet ... `
mkisofs ... | cdrecord ... tsize=${cdblocks}s -
  • -quiet β€” makes mkisofs even less verbose. No progress output at all. Silence. Peace. 🀫
  • -R, -rock β€” generates SUSP and RR records using the Rock Ridge protocol to describe the files on the ISO-9660 filesystem in more detail. The Rock Ridge protocol is what lets you add POSIX-like file metadata β€” permissions, extended time stamps, user/group ids, link counts, inode numbers, and symbolic links ✨. It also lets you archive hierarchy trees with unlimited depth, which is iconic honestly.
  • -r, -rational-rock β€” this is like -R but the file ownership and modes get set to more useful values. The uid and gid get set to zero, because they're usually only useful on the author's system and not useful to the client. All the file read bits get set true, so files and directories are globally readable on the client 🌈. If any execute bit is set for a file, all the execute bits get set, so executables are globally executable on the client. If any search bit is set for a directory, all the search bits get set, so directories are globally searchable on the client. All write bits get cleared, because the CD-Rom is gonna be mounted read-only anyway, duh. And if any of the special mode bits are set, they get cleared, because file locks are useless on a read-only filesystem and set-id bits are not it for uid 0 or gid 0 πŸ™…β€β™€οΈ. When used on Win32, the execute bit gets set on all files β€” that's a result of the lack of file permissions on Win32 and the Cygwin POSIX emulation layer. See also -uid, -gid, -dir-mode, -file-mode and -new-dir-mode.
  • -relaxed-filenames β€” lets ISO-9660 filenames include digits, upper case characters, and all other 7 bit ASCII characters (resp. anything except lowercase characters). This violates the ISO-9660 standard, but it happens to work on many systems. Use with caution ⚠️ β€” she's breaking the rules and she knows it.
  • -root dir β€” moves all files and directories into dir in the image. Essentially the same as using -graft-points and adding dir in front of every pathspec, but way easier to use πŸ’–.

dir may actually be several levels deep. It gets created with the same permissions as other graft points.

  • -rrip110 β€” creates ISO-9660 filesystem images following the old Rrip Version-1.10 standard from 1993 πŸ•°οΈ. You might need this if you know of systems that don't implement the Rrip protocol correctly and you want the filesystem to be readable by such a system. Currently no such system is known, ngl.

If a filesystem has been created with -rrip110, the Rock Ridge attributes do not include inode number information.

  • -rrip112 β€” creates ISO-9660 filesystem images following the new Rrip Version-1.12 standard from 1994. This is the default ✨.
  • -old-root dir β€” this option is necessary when writing a multisession image and the previous (or even older) session was written with -root dir. Using a directory name not found in the previous session causes mkisofs to abort with an error 😭.

Without this option, mkisofs wouldn't be able to find unmodified files and would be forced to write their data into the image once more. So wasteful.

-root and -old-root are meant to be used together for incremental backups 🫢. The initial session would e.g. use mkisofs -root backup_1 dirs. The next incremental backup with mkisofs -root backup_2 -old-root backup_1 dirs would take another snapshot of these directories. The first snapshot would be found in backup_1, the second one in backup_2, but only modified or new files need to be written into the second session. Slay.

Without these options, new files would be added and old ones would be preserved β€” but old ones would get overwritten if the file was modified. Recovering the files by copying the whole directory back from CD would also restore files that were deleted intentionally πŸ™ˆ. And accessing several older versions of a file requires support from the operating system to choose which sessions are to be mounted.

  • -short-rr-time β€” uses the short ISO-9660 time format for the file time stamps used in Rock Ridge. This time format allows representing year 1990 .. year 2155 with a granularity of one second ⏱️.
  • -s sector type, -sectype sector type β€” sets the sector type to be used for the output file with the ISO-9660 filesystem. The sector type may be one of:
    • data β€” this is the default. It results in standard CD-ROM data sectors with 2048 bytes per sector πŸ’Ύ.
    • xa1 β€” sets the sector type to CD-ROM XA mode 1 with 2056 bytes per sector. This is the official sector type for multi-session CDs, and it should be used together with the -XA option of mkisofs. It's required to write Kodak Photo CDs and Kodak Picture CDs πŸ“Έ. Use the -xa1 option from cdrecord to tell cdrecord to write CD-ROM XA mode 1 sectors. Do not use for DVD or BluRay media.
    • raw β€” sets the sector type to raw audio sectors with 2352 bytes per sector. This is reserved for future enhancements. Do not use for DVD or BluRay media.
  • -sort sort file β€” sorts file locations on the media πŸ—‚οΈ. Sorting is controlled by a file containing pairs of filenames and sorting offset weighting. If the weighting is higher, the file gets located closer to the beginning of the media; if the weighting is lower, the file gets located closer to the end of the media. There must be only one space or tabs character between the filename and the weight, and the weight must be the last characters on a line. The filename is taken to include all the characters up to, but not including, the last space or tab character on a line β€” that's so you can have space characters in, or at the end of, a filename πŸ’…. This option does not sort the order of the file names that appear in the ISO-9660 directory; it sorts the order in which the file data gets written to the CD image β€” which may be useful to optimize the data layout on a CD. See README.sort for more details.
  • -isort sort file β€” similar to -sort but the case of the filenames in the sort file is ignored πŸ™ƒ.
  • -sparc-boot img_sun4,img_sun4c,img_sun4m,img_sun4d,img_sun4e β€” see the -B option above.
  • -sparc-label label β€” sets the Sun disk label name for the Sun disk label that gets created with the -sparc-boot option β˜€οΈ.
  • -split-output β€” splits the output image into several files of approximately 1 GB each 🍰. This helps create DVD sized ISO-9660 images on operating systems without large file support. cdrecord will concatenate more than one file into a single track if writing to a DVD. To make -split-output work, the -o filename option must be specified. The resulting output images will be named: filename_00, filename_01, filename_02...
  • -stream-media-size # β€” selects streaming operation and sets the media size to # sectors. This lets you pipe the output of the tar program into mkisofs and create an ISO-9660 filesystem without needing an intermediate tar archive file 🧚. If this option is specified, mkisofs reads from stdin and creates a file with the name STREAM.IMG. The maximum size of the file (with padding) is 200 sectors less than the specified media size. If -no-pad has been specified, the file size is 50 sectors less than the specified media size. If the file is smaller, then mkisofs will write padding β€” and that may take a while 😴.
Heads up bestie: the -stream-media-size option creates simple ISO-9660 filesystems only and may not be used together with multi-session or hybrid filesystem options 🚫.
  • -stream-file-name name β€” sets the file name used with -stream-media-size # to a value different from STREAM.IMG. If this option is used, the filesystem gets created as if -iso-level 4 has been specified ✨.
  • -sunx86-boot UFS-img,,,AUX1-img β€” specifies a comma separated list of filesystem images that are needed to make a bootable CD for Solaris x86 systems 🌞.

Note that partition 1 is used for the ISO-9660 image and partition 2 is the whole disk, so partitions 1 and 2 may not be used by external partition data. The first image file is mapped to partition 0. There may be empty fields in the comma separated list, and list entries for partition 1 and 2 must be empty. The maximum number of supported partitions is 8 (although the Solaris x86 partition table could support up to 16 partitions), so it's impossible to specify more than 6 partition images. This option is required to make a bootable CD for Solaris x86 systems πŸ‘‘.

Okay so if the -sunx86-boot option has been specified, the first sector of the resulting image will contain a PC fdisk label with a Solaris type 0x82 fdisk partition that starts at offset 512 and spans the whole CD. Slay. In addition, for the Solaris type 0x82 fdisk partition, there is a SVr4 disk label at offset 1024 in the first sector of the CD. This disk label specifies slice 0 for the first (usually UFS type) filesystem image that is used to boot the PC and slice 1 for the ISO-9660 image. Slice 2 spans the whole CD, and slice 3 ... slice 7 may be used for additional filesystem images that have been specified with this option. πŸ’–

A Solaris x86 boot CD uses a 1024 byte sized primary boot that uses the El-Torito no-emulation boot mode and a secondary generic boot that is in CD sectors 1..15. For this reason, both -b bootimage -no-emul-boot and -G genboot must be specified. No cap, both are required.

  • -sunx86-label label β€” Set the SVr4 disk label name for the SVr4 disk label that is created with the -sunx86-boot option. 🏷️
  • -sysid ID β€” Specifies the system ID. There is space on the disc for 32 characters of information. This parameter can also be set in the file .mkisofsrc with SYSI=system_id. If specified in both places, the command line version is used. ✨
  • -T, -translation-table β€” Generate a file TRANS.TBL in each directory on the CDROM, which can be used on non-Rock Ridge capable systems to help establish the correct file names. There is also information present in the file that indicates the major and minor numbers for block and character devices, and each symlink has the name of the link file given. It’s giving β€œhelpful little index era.”
  • -table-name TABLE_NAME β€” Alternative translation table file name (see above). Implies the -T option. If you are creating a multi-session image you must use the same name as in the previous session. 🫢
  • -ucs-level level β€” Set Unicode conformance level in the Joliet SVD. The default level is 3. It may be set to 1..3 using this option. 🌈
  • -UDF β€” Include a UDF hybrid in the generated filesystem image. As mkisofs always creates a ISO-9660 filesystem, it is not possible to create UDF only images. Note that UDF wastes the space from sector ~20 to sector 256 at the beginning of the disk in addition to the space needed for real UDF data structures. Space tea, but make it hybrid.
  • -udf β€” Rationalized UDF with user and group set to 0 and with simplified permissions. See -r option for more information. πŸŽ€
  • -udf-symlinks β€” Support symlinks in UDF filesystems. This is the default. πŸ’…
  • -no-udf-symlinks β€” Do not support symlinks in UDF filesystems. πŸ™ˆ
  • -uid uid β€” Overrides the uid read from the source files to the value of uid. Specifying this option automatically enables Rock Ridge extensions. πŸ”₯
  • -use-fileversion β€” The option -use-fileversion allows mkisofs to use file version numbers from the filesystem. If the option is not specified, mkisofs creates a version number of 1 for all files. File versions are strings in the range ;1 to ;32767. This option is the default on VMS. ⭐
  • -U, -untranslated-filenames β€” Allows "Untranslated" filenames, completely violating the ISO-9660 standards described above. Forces on the -d, -l, -N, -allow-leading-dots, -relaxed-filenames, -allow-lowercase, -allow-multidot and -no-iso-translate flags. It allows more than one . character in the filename, as well as mixed case filenames. This is useful on HP-UX system, where the built-in CDFS filesystem does not recognize ANY extensions. Use with extreme caution. πŸ’€
  • -no-iso-translate β€” Do not translate the characters '#' and '~' which are invalid for ISO-9660 filenames. These characters are though invalid often used by Microsoft systems. This violates the ISO-9660 standard, but it happens to work on many systems. Use with caution. ⚠️
  • -V volid β€” Specifies the volume ID (volume name or label) to be written into the master block. There is space on the disc for 32 characters of information. This parameter can also be set in the file .mkisofsrc with VOLI=id. If specified in both places, the command line version is used. Note that if you assign a volume ID, this is the name that will be used as the mount point used by the Solaris volume management system and the name that is assigned to the disc on a Microsoft Win32 or Apple Mac platform. πŸ‘‘
  • -volset ID β€” Specifies the volset ID. There is space on the disc for 128 characters of information. The related Joliet entry is limited to 64 characters. This parameter can also be set in the file .mkisofsrc with VOLS=volset_id. If specified in both places, the command line version is used. 🌸
  • -volset-size # β€” Sets the volume set size to #. The volume set size is the number of CD's that are in a CD volume set. A volume set is a collection of one or more volumes, on which a set of files is recorded.

Volume Sets are not intended to be used to create a set numbered CD's that are part of e.g. a Operation System installation set of CD's. Volume Sets are rather used to record a big directory tree that would not fit on a single volume. Each volume of a Volume Set contains a description of all the directories and files that are recorded on the volumes where the sequence numbers are less than, or equal to, the assigned Volume Set Size of the current volume.

Mkisofs currently does not support a -volset-size that is larger than 1.

The option -volset-size must be specified before -volset-seqno on each command line. πŸ¦‹

  • -volset-seqno # β€” Sets the volume set sequence number to #. The volume set sequence number is the index number of the current CD in a CD set. The option -volset-size must be specified before -volset-seqno on each command line. πŸ”’
  • -v, -verbose β€” Verbose execution. If given twice on the command line, extra debug information will be printed. Double it and the tea gets deeper. πŸ“
  • -x path β€” Exclude path from being written to CDROM. path must be the complete pathname that results from concatenating the pathname given as command line argument and the path relative to this directory. Multiple paths may be excluded. Example:
mkisofs -o cd -x /local/dir1 -x /local/dir2 /local
NOTE: The -m and -x option description should both be updated, they are wrong. Both now work identical and use filename globbing. A file is excluded if either the last component matches or the whole path matches.
  • -XA β€” Generate XA iso-directory attributes with original owner and mode information. This option is required to create conforming multi session CDs as used by the Kodak Photo CD and the Kodak Picture CD. A conforming XA CD uses CD-ROM XA mode 1 sectors, see the -sector xa2 option for more information. πŸ“€
  • -xa β€” Generate XA iso-directory attributes with rationalized owner and mode information. User ID and group ID are set to 0. See -XA for more information. ✨
  • -z β€” Generate special RRIP records for transparently compressed files. This is only of use and interest for hosts that support transparent decompression, such as Linux 2.4.14 or later. You must specify the -R or -r options to enable RockRidge, and generate compressed files using the mkzftree utility before running mkisofs. Note that transparent compression is a nonstandard Rock Ridge extension. The resulting disks are only transparently readable if used on Linux. On other operating systems you will need to call mkzftree by hand to decompress the files. πŸ’œ

πŸ’… HFS OPTIONS πŸ’…

okay bestie buckle up β€” this is the Mac-flavored corner of mkisofs, and it's a whole vibe. Let's get into it. πŸ“

  • -hfs β€” makes an ISO-9660/HFS hybrid CD. slay. You're supposed to use this one together with -map, -magic, and/or the various double-dash options listed down below, iykyk.
  • -no-hfs β€” does the exact opposite: no ISO-9660/HFS hybrid CD, even if other options are out here implying that you want one. it's giving "calm down, bestie".
  • -apple β€” makes an ISO-9660 CD with Apple's extensions. Lowkey similar to -hfs, except the Apple Extensions to ISO-9660 get added instead of creating an HFS hybrid volume. Heads up though: former mkisofs versions did include Rock Ridge attributes by default if -apple was specified, and this version of mkisofs does not do that anymore. So if you want Rock Ridge attributes, you gotta specify that separately. πŸ™ˆ
  • -map mapping_file β€” uses the mapping_file to set the CREATOR and TYPE info for a file based on the filename's extension. A filename only gets mapped if it's not one of the known Apple/Unix file formats. More deets in the HFS CREATOR/TYPE section below. ✨
  • -magic magic_file β€” sets CREATOR and TYPE info using a file's magic number (usually the first few bytes of a file, bestie). The magic_file only gets used if a file isn't one of the known Apple/Unix file formats, or if the filename extension hasn't been mapped with -map. Peep the HFS CREATOR/TYPE section below for more. πŸ”₯
  • -hfs-creator CREATOR β€” sets the default CREATOR for all files. Has to be exactly 4 characters. HFS CREATOR/TYPE section below, go look. πŸ’–
  • -hfs-type TYPE β€” sets the default TYPE for all files. Also exactly 4 characters. Same drill, see the HFS CREATOR/TYPE section below. πŸ’–
  • -probe β€” searches the contents of files for all the known Apple/Unix file formats. See the HFS MACINTOSH FILE FORMATS section below for more on those. Small catch though: the only way to check for MacBinary and AppleSingle files is to open and read them, so this option may increase processing time. ngl, it's better to use one or more of the double-dash options below if you already know which Apple/Unix formats are in use. ⭐
  • -no-desktop β€” don't create (empty) Desktop files. New HFS Desktop files will get created when the CD is used on a Macintosh (and stored in the System Folder). By default, empty Desktop files are added to the HFS volume. πŸŽ€
  • -mac-name β€” uses the HFS filename as the starting point for the ISO-9660, Joliet and Rock Ridge file names. See the HFS MACINTOSH FILE NAMES section below for the full tea. πŸ¦‹
  • -boot-hfs-file driver_file β€” installs the driver_file that may make the CD bootable on a Macintosh. See the HFS BOOT DRIVER section below. (Alpha).
  • -part β€” generates an HFS partition table. By default no partition table is generated, but some older Macintosh CDROM drivers need an HFS partition table on the CDROM to even recognize a hybrid CDROM. legacy icons only πŸ’€
  • -auto AutoStart_file β€” makes the HFS CD use the QuickTime 2.0 Autostart feature to launch an application or document. The filename you give has to be the name of a document or application located at the top level of the CD, and it must be less than 12 characters. (Alpha).
  • -cluster-size size β€” sets the size in bytes of the cluster or allocation units of PC Exchange files. Implies the --exchange option. See the HFS MACINTOSH FILE FORMATS section below. 🧚
  • -hide-hfs glob β€” hides glob from the HFS volume. The file or directory will still exist in the ISO-9660 and/or Joliet directory, so like, it's not gone-gone. glob is a shell wild-card-style pattern that must match any part of the filename, and multiple globs may be excluded. Example:
mkisofs -o rom -hfs -hide-hfs '*.o' -hide-hfs foobar

would exclude all files ending in .o or called foobar from the HFS volume. Note that if you had a directory called foobar it too (and of course all its descendants) would be excluded. The glob can also be a path name relative to the source directories given on the command line. Example:

mkisofs -o rom -hfs -hide-hfs src/html src

would exclude just the file or directory called html from the src directory. Any other file or directory called html in the tree will not be excluded. Should be used with the -hide and/or -hide-joliet options. In order to match a directory name, make sure the pathname does not include a trailing / character. See README.hide for more details. 🫢

  • -hide-hfs-list file β€” a file containing a list of globs to be hidden, same as above. πŸ’…
  • -hfs-volid hfs_volid β€” volume name for the HFS partition. This is the name that gets assigned to the disc on a Macintosh and it replaces the volid used with the -V option. πŸ‘‘
  • -icon-position β€” uses the icon position information, if it exists, from the Apple/Unix file. The icons will appear in the same position as they would on a Macintosh desktop. Folder location and size on screen, its scroll positions, folder View (view as Icons, Small Icons, etc.) are also preserved. This option may become set by default in the future. (Alpha). ✨
  • -root-info file β€” sets the location, size on screen, scroll positions, folder View etc. for the root folder of an HFS volume. See README.rootinfo for more info. (Alpha)
  • -prep-boot FILE β€” PReP boot image file. Up to 4 are allowed. See README.prep_boot. (Alpha)
  • -chrp-t β€” creates a CHRP boot in boot partition 1. See -prep-boot for further info. πŸ¦‹
  • -input-hfs-charset charset β€” input charset that defines the characters used in HFS file names when used with the -mac-name option. The default charset is cp10000 (Mac Roman), and yep, the original says it twice: cp10000 (Mac Roman) cp10000 (Mac Roman). iconic redundancy. See the CHARACTER SETS and HFS MACINTOSH FILE NAMES sections below for more.
  • -output-hfs-charset charset β€” output charset that defines the characters that will be used in the HFS file names. Defaults to the input charset. See the CHARACTER SETS section below for more. πŸŽ€
  • -hfs-unlock β€” by default, mkisofs will create an HFS volume that is locked. This option leaves the volume unlocked so that other applications (e.g. hfsutils) can modify the volume. See the HFS PROBLEMS/LIMITATIONS section below for warnings about using this option β€” like, don't just do it because it's unlocked, bestie. ⚠️
  • -hfs-bless folder_name β€” "Bless" the given directory (folder). This is usually the System Folder and it's used in creating HFS bootable CDs. The name of the directory must be the whole path name as mkisofs sees it. e.g. if the given pathspec is ./cddata and the required folder is called System Folder, then the whole path name is "./cddata/System Folder" (remember to use quotes if the name contains spaces). πŸ™ˆ
  • -hfs-parms PARAMETERS β€” overrides certain parameters used to create the HFS file system. Unlikely to be used in normal circumstances. See the libhfs_iso/hybrid.h source file for details. deep lore only πŸ’€
  • --cap β€” look for AUFS CAP Macintosh files. Searches for CAP Apple/Unix file formats only. Searching for the other possible Apple/Unix file formats is disabled, unless other double dash options are given. πŸ”
  • --netatalk β€” look for NETATALK Macintosh files πŸ¦‹
  • --double β€” look for AppleDouble Macintosh files πŸ“
  • --ethershare β€” look for Helios EtherShare Macintosh files ⭐
  • --ushare β€” look for IPT UShare Macintosh files 🌈
  • --exchange β€” look for PC Exchange Macintosh files πŸ’œ
  • --sgi β€” look for SGI Macintosh files 🧚
  • --xinet β€” look for XINET Macintosh files ✨
  • --macbin β€” look for MacBinary Macintosh files πŸŽ€
  • --single β€” look for AppleSingle Macintosh files 🌸
  • --dave β€” look for Thursby Software Systems DAVE Macintosh files πŸ‘‘
  • --sfm β€” look for Microsoft's Services for Macintosh files (NT only) (Alpha) πŸ’€
  • --osx-double β€” look for MacOS X AppleDouble Macintosh files πŸ¦‹
  • --osx-hfs β€” look for MacOS X HFS Macintosh files πŸ”₯

✨ CHARACTER SETS ✨

Okay bestie, buckle up, because this is the part where file names get complicated 😭

So mkisofs handles file names in a POSIX-compliant way, treating them like strings of 8-bit characters. Cute, right? Except πŸ’€ 8-bit characters are not enough to represent every single coding for every single language. Unicode, aka ISO-10646, defines character codings that need at least 21 bits to cover all known languages. Twenty-one! And those can be represented with UTF-32, UTF-16 or UTF-8 coding.

Quick rundown, because you deserve to know:

  • UTF-32 uses a plain 32-bit coding, but it's kinda uncommon out there.
  • UCS-2 is what Microsoft uses with Win32. It's similar to UTF-16 but with the downside that it only supports a 16-bit subset of all codes (unless surrogates get involved), and 16-bit characters are not compliant with the POSIX filesystem interface. Not it. πŸ™ˆ

Modern UNIX operating systems may use UTF-8 coding for filenames, and this one slays because it lets you use the complete Unicode code set. Each 32-bit character is represented by one or more 8-bit characters. Here's the tea:

  • If a character is coded in ISO-8859-1 (used in Central Europe and North America), it maps 1:1 to a UTF-32 or UTF-16 coded Unicode character.
  • If a character is coded in 7-Bit ASCII (used in the USA and other countries with limited character sets), it maps 1:1 to a UTF-32, UTF-16 or UTF-8 coded Unicode character.
  • Character codes that can't be represented as a single byte in UTF-8 (typically when the value is > 0x7F) use escape sequences that map to more than one 8-bit character.

And like… if every operating system used UTF-8, mkisofs wouldn't even need to recode characters in file names at all. Iconic dream, honestly. 😭 Unfortunately, Apple uses completely nonstandard codings, and Microsoft uses a Unicode coding that isn't compatible with the POSIX filename interface. So here we are.


For all the non-UTF-8 coded operating systems, the actual character that each byte represents depends on the character set β€” or codepage, which is the name Microsoft uses β€” that the local operating system is running. And the characters in a character set will reflect the region or natural language the user is working in.

Usually it goes like this:

  • 0x00-0x1f are control characters
  • 0x20-0x7f are the 7 bit ASCII characters
  • (on PC's and Mac's) 0x80-0xff are used for other characters

Unfortunately, even this doesn't follow the ISO standards, which reserve the range 0x80-0x9f for control characters and only allow 0xa0-0xff for other characters. Standards? Never heard of her. πŸ’…

And because there are way, way more than 256 characters/symbols in use, only a small subset actually gets represented in any given character set. Which means the same character code can represent a different character in a different character set. So a file name generated in, say, central Europe might not display the same character when you view it on a machine in, say, eastern Europe. Rude, but true.

It gets even messier, because different operating systems use different character sets for the same region or language. Example time πŸ“ the character code for "small e with acute accent" could be:

  • character code 0x82 on a PC
  • code 0x8e on a Macintosh
  • code 0xe9 on a UNIX system

And ngl, while the codings used on a PC or Mac are nonstandard, Unicode codes this character as 0x00000000e9 β€” which is basically the same value most UNIX systems use. Slay for UNIX I guess. πŸ‘‘

So as long as not every operating system and application uses the Unicode character set as the basis for file names in one unique way, you may need to specify which character set your file names use in, and which character set the file names should appear on the CD. And there are four options to do exactly that:

  • -input-charset β€” Defines the local character set you're using on your host machine. Any character set conversions that take place will use this character set as the starting point. The default input character sets are cp437 on DOS based systems and iso8859-1 on all other systems. Oh, and if the -J option is given, then the Unicode equivalents of the input character set will be used in the Joliet directory. Using the -jcharset option is the same as using the -input-charset and -J options. Two-for-one, we love to see it. πŸ’–
  • -output-charset β€” Defines the character set that will be used for the Rock Ridge names on the CD. Defaults to the input character set. Only likely to be useful if you're on a non-Unix platform β€” e.g. using mkisofs on a Microsoft Win32 machine to create Rock Ridge CDs. If you're using mkisofs on a Unix machine, it's likely the output character set will be the same as the input character set anyway.
  • -input-hfs-charset β€” Defines the HFS character set used for HFS file names decoded from any of the various Apple/Unix file formats. Only useful when used with the -mac-name option. See the HFS MACINTOSH FILE NAMES section for more info. Defaults to cp10000 (Mac Roman).
  • -output-hfs-charset β€” Defines the HFS character set used to create HFS file names from the input character set in use. In most cases this will be from the character set given with the -input-charset option. Defaults to the input HFS character set.

The default character set is built right into mkisofs. 🫢 A number of further character sets get read in from the filesystem by mkisofs from a directory relatively to the install path. Wanna see the list? Just run:

mkisofs -input-charset help

Additional character sets from iconv(1) may also be used on systems that support iconv(1). In that case, call iconv -l to get a list of valid character sets from this coding method. And to force an iconv(1) based coding, use iconv:name instead of name for the character set. Little prefix, big difference. ✨

If you're using non iconv(1) based character sets, you can read additional character sets from a file for any of the character set options β€” just give a filename as the argument to the option. A given character set will be read from a file whenever the supplied name contains a /.

The format of these character set files is the same as the mapping files available from http://www.unicode.org/Public/MAPPINGS. And that format is:

Column #1 is the input byte code (in hex as 0xXX)
Column #2 is the Unicode (in hex as 0xXXXX)
Rest of the line is ignored.

Any blank line, any line without two (or more) columns in the above format, or any comment line (starting with the # character) gets ignored without any warnings. And any missing input code is mapped to Unicode character 0x0000. No drama, no complaints. 😌

Heads up bestie: there is no support for 16 bit UNICODE (UTF-16) or 32 bit UNICODE (UTF-32) coding, because that coding is not POSIX compliant. There should be support for UTF-8 UNICODE coding, which is compatible to POSIX filenames and supported by modern UNIX implementations such as Solaris.

A 1:1 character set mapping can be defined by using the keyword default as the argument to any of the character set options. That's the behaviour of older (v1.12) versions of mkisofs β€” vintage vibes. πŸŽ€

One thing to keep in mind: the ISO-9660 file names generated from the input filenames are not converted from the input character set. And honestly why would they be β€” the ISO-9660 character set is a very limited subset of the ASCII characters, so any conversion would be pointless.

And finally, the safety net: any character that mkisofs can not convert will be replaced with a _ character. Simple as that. πŸ¦‹

✨ HFS CREATOR/TYPE ✨

Okay bestie, so every Macintosh file has two little properties attached to it: the CREATOR (which app made the file) and the TYPE (what kind of data is inside). Both are exactly 4-letter strings, no cap. Usually this is what lets a Macintosh user double-click a file and launch the correct application, etc. You can peek at the CREATOR and TYPE of a particular file by using something like ResEdit (or similar) on a Macintosh.

The CREATOR and TYPE info is stored in all the various Apple/Unix encoded files. For other files, you can base the CREATOR and TYPE on the filename’s extension using a mapping file (the -map option) and/or using the magic number (usually a signature in the first few bytes) of a file (the -magic option). If both options are given, their order on the command line is important. If the -map option comes first, then a filename extension match is attempted before a magic number match. But if the -magic option comes first, then a magic number match is attempted before a filename extension match.

If a mapping or magic file is not used, or no match is found, then the default CREATOR and TYPE for all regular files can be set by using entries in the .mkisofsrc file or by using the -hfs-creator and/or -hfs-type options. Otherwise the default CREATOR and TYPE are 'unix' and 'TEXT'.

The format of the mapping file is the same afpfile format as used by aufs. This file has five columns for the extension, file translation, CREATOR, TYPE and Comment. Lines starting with the '#' character are comment lines and are ignored. An example file would be like:

# Example filename mapping file
#
# EXTN   XLate   CREATOR   TYPE     Comment
.tif     Raw     '8BIM'    'TIFF'   "Photoshop TIFF image"
.hqx     Ascii   'BnHq'    'TEXT'   "BinHex file"
.doc     Raw     'MSWD'    'WDBN'   "Word file"
.mov     Raw     'TVOD'    'MooV'   "QuickTime Movie"
*        Ascii   'ttxt'    'TEXT'   "Text file"

Where:

  • The first column EXTN defines the Unix filename extension to be mapped. The default mapping for any filename extension that doesn’t match is defined with the "*" character.
  • The Xlate column defines the type of text translation between the Unix and Macintosh file. It is ignored by mkisofs, but is kept to be compatible with aufs(1). Although mkisofs does not alter the contents of a file, if a binary file has its TYPE set as 'TEXT', it may be read incorrectly on a Macintosh. Therefore a better choice for the default TYPE may be '????'.
  • The CREATOR and TYPE keywords must be 4 characters long and enclosed in single quotes.
  • The comment field is enclosed in double quotes β€” it is ignored by mkisofs, but is kept to be compatible with aufs.

The format of the magic file is almost identical to the magic(4) file used by the Linux file(1) command β€” the routines for reading and decoding the magic file are based on the Linux file(1) command.

This file has four tab-separated columns for the byte offset, type, test and message. Lines starting with the '#' character are comment lines and are ignored. An example file would be like:

# Example magic file
#
# off   type      test       message
0       string    GIF8       8BIM GIFf  GIF image
0       beshort   0xffd8     8BIM JPEG  image data
0       string    SIT!       SIT! SIT!  StuffIt Archive
0       string    \037\235   LZIV ZIVU  standard unix compress
0       string    \037\213   GNUz ZIVU  gzip compressed data
0       string    %!         ASPS TEXT  Postscript
0       string    \004%!     ASPS TEXT  PC Postscript with a ^D to start
4       string    moov       txtt MooV  QuickTime movie file (moov)
4       string    mdat       txtt MooV  QuickTime movie file (mdat)

The format of the file is described in the magic(4) man page. The only difference here is that for each entry in the magic file, the message for the initial offset must be 4 characters for the CREATOR followed by 4 characters for the TYPE β€” white space is optional between them. Any other characters on this line are ignored. Continuation lines (starting with a '>') are also ignored, i.e. only the initial offset lines are used.

Using the -magic option may significantly increase processing time, since each file has to be opened and read to find its magic number.

In summary, for all files, the default CREATOR is 'unix' and the default TYPE is 'TEXT'. These can be changed by using entries in the .mkisofsrc file or by using the -hfs-creator and/or -hfs-type options.

If a file is in one of the known Apple/Unix formats (and the format has been selected), then the CREATOR and TYPE are taken from the values stored in the Apple/Unix file.

Other files can have their CREATOR and TYPE set from their filename extension (the -map option), or their magic number (the -magic option). If the default match is used in the mapping file, then these values override the default CREATOR and TYPE.

A full CREATOR/TYPE database can be found at http://www.angelfire.com/il/szekely/index.html

✨ HFS MACINTOSH FILE FORMATS ✨

okay bestie, buckle up β€” this is the part where things get spicy. Macintosh files have two parts, and they're called the Data fork and the Resource fork. Either one can be empty. But Unix (and honestly most other OSs) can only cope with files that have one part, i.e. one fork. And it gets worse: Macintosh files also carry a bunch of attributes, and probably the two most important ones are TYPE and CREATOR. Unix has literally no concept of these attribute types. none. zero. 🫠

Like, a Macintosh file might be a JPEG image where the actual image lives in the Data fork and a cute little desktop thumbnail lives in the Resource fork. And it's usually the data fork info that's useful across platforms, iykyk.

So to store a Macintosh file on a Unix filesystem, somebody had to find a way to handle both forks and the extra attributes (these get called the finder info, fyi). And unfortunately it seems like every single software package that stores Macintosh files on Unix picked a completely different storage method. classic. 😭

The Apple/Unix formats that mkisofs (partially) supports are:

  • CAP AUFS format β€” Data fork stored in a file. Resource fork in subdirectory .resource with same filename as data fork. Finder info in .finderinfo subdirectory with same filename.
  • AppleDouble/Netatalk β€” Data fork stored in a file. Resource fork stored in a file with same name prefixed with "%". Finder info also stored in same "%" file. Netatalk uses the same format, but the resource fork/finderinfo stored in subdirectory .AppleDouble with same name as data fork.
  • AppleSingle β€” Data structures similar to above, except both forks and finder info are stored in one file.
  • Helios EtherShare β€” Data fork stored in a file. Resource fork and finder info together in subdirectory .rsrc with same filename as data fork.
  • IPT UShare β€” Very similar to the EtherShare format, but the finder info is stored slightly differently.
  • MacBinary β€” Both forks and finder info stored in one file.
  • Apple PC Exchange β€” Used by Macintoshes to store Apple files on DOS (FAT) disks. Data fork stored in a file. Resource fork in subdirectory resource.frk (or RESOURCE.FRK). Finder info as one record in file finder.dat (or FINDER.DAT). Separate finder.dat for each data fork directory.
Note: mkisofs needs to know the native FAT cluster size of the disk that the PC Exchange files are on (or have been copied from). This size is given by the -cluster-size option. The cluster or allocation size can be found by using the DOS utility CHKDSK.

May not work with PC Exchange v2.2 or higher files (available with MacOS 8.1). DOS media containing PC Exchange files should be mounted as type msdos (not vfat) when using Linux.

  • SGI/XINET β€” Used by SGI machines when they mount HFS disks. Data fork stored in a file. Resource fork in subdirectory .HSResource with same name. Finder info as one record in file .HSancillary. Separate .HSancillary for each data fork directory.
  • Thursby Software Systems DAVE β€” Allows Macintoshes to store Apple files on SMB servers. Data fork stored in a file. Resource fork in subdirectory resource.frk. Uses the AppleDouble format to store resource fork.
  • Services for Macintosh β€” Format of files stored by NT Servers on NTFS filesystems. Data fork is stored as "filename". Resource fork stored as a NTFS stream called "filename:AFP_Resource". The finder info is stored as a NTFS stream called "filename:Afp_AfpInfo". These streams are normally invisible to the user.
Warning: mkisofs only partially supports the SFM format. If an HFS file or folder stored on the NT server contains an illegal NT character in its name, then NT converts these characters to Private Use Unicode characters. The characters are: " * / < > ? | β€” also a space or period if it is the last character of the file name, character codes 0x01 to 0x1f (control characters) and Apple's apple logo.

Unfortunately, these private Unicode characters are not readable by the mkisofs NT executable. Therefore any file or directory name containing these characters will be ignored β€” including the contents of any such directory. πŸ’€

  • MacOS X AppleDouble β€” When HFS/HFS+ files are copied or saved by MacOS X on to a non-HFS file system (e.g. UFS, NFS etc.), the files are stored in AppleDouble format. Data fork stored in a file. Resource fork stored in a file with same name prefixed with "._". Finder info also stored in same "._" file.
  • MacOS X HFS (Alpha) β€” Not really an Apple/Unix encoding, but actual HFS/HFS+ files on a MacOS X system. Data fork stored in a file. Resource fork stored in a pseudo file with the same name with the suffix '/rsrc'. The finderinfo is only available via a MacOS X library call.
Notes: (also see README.macosx)

Only works when used on MacOS X.

If a file is found with a zero length resource fork and empty finderinfo, it is assumed not to have any Apple/Unix encoding β€” therefore a TYPE and CREATOR can be set using other methods. πŸŽ€


mkisofs will attempt to set the CREATOR, TYPE, date and possibly other flags from the finder info. Additionally, if it exists, the Macintosh filename is set from the finder info, otherwise the Macintosh name is based on the Unix filename β€” see the HFS MACINTOSH FILE NAMES section below. πŸ‘‘

When using the -apple option, the TYPE and CREATOR are stored in the optional System Use or SUSP field in the ISO-9660 Directory Record β€” in much the same way as the Rock Ridge attributes are. In fact, to make life easy, the Apple extensions are added at the beginning of the existing Rock Ridge attributes (i.e. to get the Apple extensions you get the Rock Ridge extensions as well). slay, two for one πŸ’…

The Apple extensions require the resource fork to be stored as an ISO-9660 associated file. This is just like any normal file stored in the ISO-9660 filesystem except that the associated file flag is set in the Directory Record (bit 2). This file has the same name as the data fork (the file seen by non-Apple machines). Associated files are normally ignored by other OSs.

When using the -hfs option, the TYPE and CREATOR plus other finder info, are stored in a separate HFS directory, not visible on the ISO-9660 volume. The HFS directory references the same data and resource fork files described above.

In most cases, it is better to use the -hfs option instead of the -apple option, as the latter imposes the limited ISO-9660 characters allowed in filenames. However, the Apple extensions do give the advantage that the files are packed on the disk more efficiently and it may be possible to fit more files on a CD β€” important when the total size of the source files is approaching 650MB. πŸ”₯

πŸ“ HFS MACINTOSH FILE NAMES πŸ“

okay so bestie, where possible, the HFS filename that is stored with an Apple/Unix file is used for the HFS part of the CD. But not all the Apple/Unix encodings store the HFS filename with the finderinfo. In those cases, the Unix filename is used β€” with escaped special characters. Special characters include '/' and characters with codes over 127. no cap, this matters πŸ’…

Aufs escapes these characters by using ":" followed by the character code as two hex digits. Netatalk and EtherShare have a similar scheme, but uses "%" instead of a ":". iykyk.

If mkisofs can't find an HFS filename, then it uses the Unix name, with any %xx or :xx characters (xx == two hex digits) converted to a single character code. If "xx" are not hex digits ([0-9a-fA-F]), then they are left alone β€” although any remaining ":" is converted to "%" as colon is the HFS directory separator. Care must be taken, as an ordinary Unix file with %xx or :xx will also be converted. e.g.

This:2fFile   converted to This/File

This:File     converted to This%File

This:t7File   converted to This%t7File

Although HFS filenames appear to support upper and lower case letters, the filesystem is case insensitive. i.e. the filenames "aBc" and "AbC" are the same. If a file is found in a directory with the same HFS name, then mkisofs will attempt, where possible, to make a unique name by adding '_' characters to one of the filenames. lowkey iconic behavior ✨

If an HFS filename exists for a file, then mkisofs can use this name as the starting point for the ISO-9660, Joliet and Rock Ridge filenames using the -mac-name option. Normal Unix files without an HFS name will still use their Unix name. e.g.

If a MacBinary (or PC Exchange) file is stored as someimage.gif.bin on the Unix filesystem, but contains a HFS file called someimage.gif, then this is the name that would appear on the HFS part of the CD. However, as mkisofs uses the Unix name as the starting point for the other names, then the ISO-9660 name generated will probably be SOMEIMAG.BIN and the Joliet/Rock Ridge would be someimage.gif.bin. Although the actual data (in this case) is a GIF image. This option will use the HFS filename as the starting point and the ISO-9660 name will probably be SOMEIMAG.GIF and the Joliet/Rock Ridge would be someimage.gif. obsessed with the glow-up tbh πŸ¦‹

Using the -mac-name option will not currently work with the -T option β€” the Unix name will be used in the TRANS.TBL file, not the Macintosh name. not me finding out the hard way 😭

The character set used to convert any HFS file name to a Joliet/Rock Ridge file name defaults to cp10000 (Mac Roman). The character set used can be specified using the -input-hfs-charset option. Other built in HFS character sets are: cp10006 (MacGreek), cp10007 (MacCyrillic), cp10029 (MacLatin2), cp10079 (MacIcelandic) and cp10081 (MacTurkish). slay for multilingual besties 🌈

Note: the character codes used by HFS file names taken from the various Apple/Unix formats will not be converted as they are assumed to be in the correct Apple character set. Only the Joliet/Rock Ridge names derived from the HFS file names will be converted. fr fr, that's the vibe check.

The existing mkisofs code will filter out any illegal characters for the ISO-9660 and Joliet filenames, but as mkisofs expects to be dealing directly with Unix names, it leaves the Rock Ridge names as is. But as '/' is a legal HFS filename character, the -mac-name option converts '/' to '_' in Rock Ridge filenames. periodt πŸ’…

If the Apple extensions are used, then only the ISO-9660 filenames will appear on the Macintosh. However, as the Macintosh ISO-9660 drivers can use Level 2 filenames, then you can use options like -allow-multidot without problems on a Macintosh β€” still take care over the names, for example this.file.name will be converted to THIS.FILE i.e. only have one '.', also filename abcdefgh will be seen as ABCDEFGH but abcdefghi will be seen as ABCDEFGHI. i.e. with a '.' at the end β€” don't know if this is a Macintosh problem or mkisofs/mkhybrid problem. All filenames will be in upper case when viewed on a Macintosh. Of course, DOS/Win3.X machines will not be able to see Level 2 filenames... πŸ’€


πŸŽ€ HFS CUSTOM VOLUME/FOLDER ICONS πŸŽ€

To give a HFS CD a custom icon, make sure the root (top level) folder includes a standard Macintosh volume icon file. To give a volume a custom icon on a Macintosh, an icon has to be pasted over the volume's icon in the "Get Info" box of the volume. This creates an invisible file called Icon\r (\r is the 'carriage return' character) in the root folder. main character energy for your CD πŸ’–

A custom folder icon is very similar β€” an invisible file called Icon\r exists in the folder itself.

Probably the easiest way to create a custom icon that mkisofs can use, is to format a blank HFS floppy disk on a Mac, paste an icon to its "Get Info" box. If using Linux with the HFS module installed, mount the floppy using something like:

mount -t hfs /dev/fd0 /mnt/floppy

The floppy will be mounted as a CAP file system by default. Then run mkisofs using something like:

mkisofs --cap -o output source_dir /mnt/floppy

If you are not using Linux, then you can use the hfsutils to copy the icon file from the floppy. However, care has to be taken, as the icon file contains a control character. e.g.

hmount /dev/fd0
hdir -a
hcopy -m Icon^V^M icon_dir/icon

Where '^V^M' is control-V followed by control-M. Then run mkisofs by using something like:

mkisofs --macbin -o output source_dir icon_dir

The procedure for creating/using custom folder icons is very similar β€” paste an icon to folder's "Get Info" box and transfer the resulting Icon\r file to the relevant directory in the mkisofs source tree. πŸŽ€

You may want to hide the icon files from the ISO-9660 and Joliet trees. lowkey tidy vibes ✨

To give a custom icon to a Joliet CD, follow the instructions found at: http://www.fadden.com/cdrfaq/faq03.html#[3-21]


πŸ‘‘ HFS BOOT DRIVER πŸ‘‘

It may be possible to make the hybrid CD bootable on a Macintosh. not guaranteed, bestie, but maybe πŸ‘€

A bootable HFS CD requires an Apple CD-ROM (or compatible) driver, a bootable HFS partition and the necessary System, Finder, etc. files.

A driver can be obtained from any other Macintosh bootable CD-ROM using the apple_driver utility. This file can then be used with the -boot-hfs-file option. iykyk.

The HFS partition (i.e. the hybrid disk in our case) must contain a suitable System Folder, again from another CD-ROM or disk.

For a partition to be bootable, it must have its boot block set. The boot block is in the first two blocks of a partition. For a non-bootable partition the boot block is full of zeros. Normally, when a System file is copied to partition on a Macintosh disk, the boot block is filled with a number of required settings β€” unfortunately I don't know the full spec for the boot block, so I'm guessing that the following will work OK. it's giving "trust me bro" but in a manual 😭

Therefore, the utility apple_driver also extracts the boot block from the first HFS partition it finds on the given CD-ROM and this is used for the HFS partition created by mkisofs.

🚨 PLEASE NOTE 🚨

By using a driver from an Apple CD and copying Apple software to your CD, you become liable to obey Apple Computer, Inc. Software License Agreements. fr fr, read the fine print bestie πŸ’…

πŸ”₯ EL TORITO BOOT INFORMATION TABLE πŸ”₯

When the -boot-info-table option is given, mkisofs will modify the boot file specified by the -b option by inserting a 56-byte "boot information table" at offset 8 in the file. This modification is done in the source filesystem, so make sure you use a copy if this file is not easily recreated! This file contains pointers which may not be easily or reliably obtained at boot time. not me warning you twice, it's important 😭

The format of this table is as follows; all integers are in section 7.3.1 ("little endian") format.

  • Offset 8 β€” Name bi_pvd β€” Size 4 bytes β€” Meaning: LBA of primary volume descriptor
  • Offset 12 β€” Name bi_file β€” Size 4 bytes β€” Meaning: LBA of boot file
  • Offset 16 β€” Name bi_length β€” Size 4 bytes β€” Meaning: Boot file length in bytes
  • Offset 20 β€” Name bi_csum β€” Size 4 bytes β€” Meaning: 32-bit checksum
  • Offset 24 β€” Name bi_reserved β€” Size 40 bytes β€” Meaning: Reserved

The 32-bit checksum is the sum of all the 32-bit words in the boot file starting at byte offset 64. All linear block addresses (LBAs) are given in CD sectors (normally 2048 bytes). math girlies rise 🧚✨

🌸 CONFIGURATION 🌸

okay so here's the vibe: mkisofs goes hunting for a file called .mkisofsrc, and it's gonna check in a very specific order, bestie, so pay attention πŸ’…

  1. first it peeks in the current working directory
  2. then it checks your user's home directory
  3. and finally it looks in the directory in which the mkisofs binary is stored

This file is assumed to contain a series of lines of the form TAG=value, and in this way you can specify certain options. The case of the tag is not significant (iconic, we love a chill parser). Some fields in the volume header are not settable on the command line, but can be altered through this facility β€” so this file is genuinely the main character for those πŸŽ€

Comments may be placed in this file, using lines which start with a hash (#) character ✨

  • APPI β€” the application identifier should describe the application that will be on the disc. There is space on the disc for 128 characters of information. The related Joliet entry is limited to 64 characters. May be overridden using the -A command line option.
  • COPY β€” the copyright information, often the name of a file on the disc containing the copyright notice. There is space in the disc for 37 characters of information. The related Joliet entry is limited to 18 characters. May be overridden using the -copyright command line option.
  • ABST β€” the abstract information, often the name of a file on the disc containing an abstract. There is space in the disc for 37 characters of information. The related Joliet entry is limited to 18 characters. May be overridden using the -abstract command line option.
  • BIBL β€” the bibliographic information, often the name of a file on the disc containing a bibliography. There is space in the disc for 37 characters of information. The related Joliet entry is limited to 18 characters. May be overridden using the -bilio command line option.
  • PREP β€” this should describe the preparer of the CDROM, usually with a mailing address and phone number. There is space on the disc for 128 characters of information. The related Joliet entry is limited to 64 characters. May be overridden using the -p command line option.
  • PUBL β€” this should describe the publisher of the CDROM, usually with a mailing address and phone number. There is space on the disc for 128 characters of information. The related Joliet entry is limited to 64 characters. May be overridden using the -publisher command line option.
  • SYSI β€” the System Identifier. There is space on the disc for 32 characters of information. May be overridden using the -sysid command line option.
  • VOLI β€” the Volume Identifier. There is space on the disc for 32 characters of information. May be overridden using the -V command line option.
  • VOLS β€” the Volume Set Name. There is space on the disc for 128 characters of information. The related Joliet entry is limited to 64 characters. May be overridden using the -volset command line option.
  • HFS_TYPE β€” the default TYPE for Macintosh files. Must be exactly 4 characters. May be overridden using the -hfs-type command line option.
  • HFS_CREATOR β€” the default CREATOR for Macintosh files. Must be exactly 4 characters. May be overridden using the -hfs-creator command line option.

mkisofs can also be configured at compile time with defaults for many of these fields. See the file defaults.h. 🫢


πŸ’– EXAMPLES πŸ’–

okay this is the part where it gets good, bestie β€” real commands, copy-paste energy, let's GO πŸš€

To create a vanilla ISO-9660 filesystem image in the file cd.iso, where the directory cd_dir will become the root directory of the CD ISO image, call:

% mkisofs -o cd.iso cd_dir

To create a CD with Rock Ridge extensions of the source directory cd_dir:

% mkisofs -o cd.iso -R cd_dir

To create a CD with Rock Ridge extensions of the source directory cd_dir where all files have at least read permission and all files are owned by root, call:

% mkisofs -o cd.iso -r cd_dir

To write a tar archive directly to a CD that will later contain a simple ISO-9660 filesystem with the tar archive call:

% star -c . | mkisofs -stream-media-size 333000 | \
        cdrecord dev=b,t,l -dao tsize=333000s -

To create a HFS hybrid CD with the Joliet and Rock Ridge extensions of the source directory cd_dir:

% mkisofs -o cd.iso -R -J -hfs cd_dir

To create a HFS hybrid CD from the source directory cd_dir that contains Netatalk Apple/Unix files:

% mkisofs -o cd.iso --netatalk cd_dir

To create a HFS hybrid CD from the source directory cd_dir, giving all files CREATOR and TYPES based on just their filename extensions listed in the file "mapping".:

% mkisofs -o cd.iso -map mapping cd_dir

To create a CD with the 'Apple Extensions to ISO-9660', from the source directories cd_dir and another_dir. Files in all the known Apple/Unix format are decoded and any other files are given CREATOR and TYPE based on their magic number given in the file "magic":

% mkisofs -o cd.iso -apple -magic magic -probe \
        cd_dir another_dir

The following example puts different files on the CD that all have the name README, but have different contents when seen as a ISO-9660/RockRidge, Joliet or HFS CD 🌈

Current directory contains:

% ls -F
README.hfs     README.joliet  README.unix    cd_dir/

The following command puts the contents of the directory cd_dir on the CD along with the three README files β€” but only one will be seen from each of the three filesystems:

% mkisofs -o cd.iso -hfs -J -r -graft-points \
        -hide README.hfs -hide README.joliet \
        -hide-joliet README.hfs -hide-joliet README.unix \
        -hide-hfs README.joliet -hide-hfs README.unix \
        README=README.hfs README=README.joliet \
        README=README.unix cd_dir

i.e. the file README.hfs will be seen as README on the HFS CD and the other two README files will be hidden. Similarly for the Joliet and ISO-9660/RockRidge CD.

There are probably all sorts of strange results possible with combinations of the hide options ... 😭 (this is the manpage saying "we're not gonna stop you, but we're also not gonna save you")

To create a DVD-Audio of the DVD-Audio compliant source directory DVD:

% mkisofs -o dvda.iso -dvd-audio DVD

πŸ‘‘ AUTHOR πŸ‘‘

Eric Youngdale <ericy@gnu.ai.mit.edu> or <eric@andante.org> wrote the first versions (1993 ... 1998) of the mkisofs utility. The copyright for old versions of the mkisofs utility is held by Yggdrasil Computing, Incorporated. Joerg Schilling wrote the SCSI transport library and its adaptation layer to mkisofs and newer parts (starting from 1997) of the utility. Joerg Schilling is the primary maintainer since 1999, this makes mkisofs Copyright (C) 1997-2014 Joerg Schilling.

HFS hybrid code Copyright (C) James Pearson 1997 ... 2001.

libhfs code Copyright (C) 1996, 1997 Robert Leslie.

libfile code Copyright (C) Ian F. Darwin 1986, 1987, 1989, 1990, 1991, 1992, 1994, 1995.


⭐ NOTES ⭐

Mkisofs may safely be installed suid root. This may be needed to allow mkisofs to read the previous session when creating a multi session image. (yes, suid root, and it's safe β€” the manpage said it, not me πŸ’…)

mkisofs is not based on the standard mk*fs tools for unix, because we must generate a complete copy of an existing filesystem on a disk in the ISO-9660 filesystem. The name mkisofs is probably a bit of a misnomer, since it not only creates the filesystem, but it also populates it as well. However, the appropriate tool name for a UNIX tool that creates populated filesystems β€” mkproto β€” is not well known. πŸ’€

If mkisofs is creating a filesystem image with Rock Ridge attributes and the directory nesting level of the source directory tree is too much for ISO-9660, mkisofs will do deep directory relocation. This results in a directory called RR_MOVED in the root directory of the CD. You cannot avoid this directory in the directory tree that is visible with ISO-9660 but it it automatically hidden in the Rock Ridge tree. πŸ¦‹

The sparc boot support that is implemented with the -sparc-boot options completely follows the official Sparc CD boot requirements from the Boot prom in Sun Sparc systems. Some Linux distributions for Sparc systems use a boot loader called SILO that unfortunately is not Sparc CD boot compliant. It is annoyingly to see that the Authors of SILO don't fix SILO but instead provide a completely unneeded "patch" to mkisofs that incorporates far more source than the fix for SILO would need. 😭 (the manpage is venting, and honestly? valid.)


πŸ’€ BUGS πŸ’€

  • Does not properly read relocated directories in multi-session mode when adding data.

Any relocated deep directory is lost if the new session does not include the deep directory.

Repeat by: create first session with deep directory relocation then add new session with a single dir that differs from the old deep path.

  • Does not re-use RR_MOVED when doing multi-session from TRANS.TBL

There may be some other ones. Please, report them to the author. πŸ™ˆ

πŸ’€ HFS PROBLEMS/LIMITATIONS πŸ’€

okay bestie, this is the part where we get real about the ✨fine print✨. I had to make a bunch of assumptions about how I expect the modified libhfs routines to work β€” and like, sometimes there are situations I literally haven't thought of, or I just haven't come across them yet when those assumptions lowkey fall apart. So ngl, I can't guarantee mkisofs will do exactly what you expect (though fr fr, I haven't hit a major problem yet πŸ’…). Most of the HFS features work just fine, but some of them aren't fully tested β€” those are the ones marked as Alpha above, iykyk. πŸ‘‘

So here's the tea 🍡, the HFS filesystem looks like it supports upper and lower case letters, but it's actually case insensitive. Like, the filenames "aBc" and "AbC" are literally the same thing to it. If a file shows up in a directory with the same HFS name, mkisofs will attempt β€” where possible β€” to make a unique name by adding '_' characters to one of the filenames. Cute, right? πŸŽ€

And if HFS file/directory names share the first 31 characters, they get _N' (where N == decimal number) substituted in place of the last few characters to generate unique names. Yes, that apostrophe is really there, don't @ me. 😭


πŸ¦‹ grafting: proceed with care πŸ¦‹

Care must be taken when "grafting" Apple/Unix files or directories (see above for the method and syntax involved, bestie). It is not possible to use a new name for an Apple/Unix encoded file/directory. Like, for example β€” if an Apple/Unix encoded file called "oldname" is to be added to the CD, then you can NOT use the command line:

mkisofs -o output.raw -hfs -graft-points newname=oldname cd_dir

mkisofs will be unable to decode "oldname" in that case. πŸ™ˆ However β€” and this is the slay part β€” you can graft Apple/Unix encoded files or directories, just as long as you don't attempt to give them new names like above. πŸ’–


🌈 multisession tea 🌈

When you're creating an HFS volume with the multisession options, -M and -C, only files in the last session will be in the HFS volume. i.e. mkisofs can not add existing files from previous sessions to the HFS volume. That's just how it is. πŸ’€

But wait β€” if each session is created with the -part option, then each session will appear as separate volumes when mounted on a Mac. In that case, it's genuinely worth using the -V or -hfs-volid option to give each session a unique volume name, otherwise every single "volume" will show up on the Desktop with the same name and it's giving chaos energy. 😭

Symbolic links (as with all other non-regular files) are not added to the HFS directory. Periodt.


πŸ“ size things (the allocation block saga) πŸ“

Hybrid volumes may be larger than pure ISO-9660 volumes containing the same data. In some cases β€” like DVD sized volumes β€” the hybrid volume may be significantly larger. As an HFS volume gets bigger, so does the allocation block size (that's the smallest amount of space a file can occupy, bestie). For a 650Mb CD, the allocation block is 10Kb, and for a 4.7Gb DVD it will be about 70Kb. Numbers don't lie. πŸ“

The maximum number of files in an HFS volume is about 65500 β€” although the real limit will be somewhat less than this. Close enough, honestly.


🧚 hfsutils + the locked volume situation 🧚

The resulting hybrid volume can be accessed on a Unix machine by using the hfsutils routines. However, no changes can be made to the volume as it is set as locked. The option -hfs-unlock will create an output image that is unlocked β€” however, no changes should be made to the contents of the volume (unless you really know what you are doing) as it's not a "real" HFS volume. Like, it's giving cosplay. Don't trust it. πŸ‘€

Using the -mac-name option will not currently work with the -T option β€” the Unix name will be used in the TRANS.TBL file, not the Macintosh name.

⭐ misc warnings, aka the fine print ⭐

  • Although mkisofs does not alter the contents of a file, if a binary file has its TYPE set as 'TEXT', it may be read incorrectly on a Macintosh. Therefore a better choice for the default TYPE may be '????' πŸ’…
  • The -mac-boot-file option may not work at all… 🫠
  • May not work with PC Exchange v2.2 or higher files (available with MacOS 8.1). DOS media containing PC Exchange files should be mounted as type msdos (not vfat) when using Linux. no cap.
  • The SFM format is only partially supported β€” see the HFS MACINTOSH FILE FORMATS section above. πŸŽ€
  • It is not possible to use the the -sparc-boot or -generic-boot options with the -boot-hfs-file the -prep-boot or -chrp-boot options. (yes, the original says "the the" and "the" β€” I'm keeping it exactly, don't come for me 😭)
  • mkisofs should be able to create HFS hybrid images over 4Gb, although this has not been fully tested. Fingers crossed bestie. 🀞

πŸ‘‘ SEE ALSO πŸ‘‘

cdrecord(1), mkzftree(1), sfind(1), magic(5), apple_driver(8). Go read those too, they're iconic in their own way πŸ’–


✨ FUTURE IMPROVEMENTS ✨

Some sort of gui interface. That's it. That's the whole wishlist. πŸŽ€


🌸 AVAILABILITY 🌸

mkisofs is available as part of the cdrecord package from https://sourceforge.net/projects/cdrtools/files/

hfsutils from ftp://ftp.mars.org/pub/hfs

mkzftree is available as part of the zisofs-tools package from ftp://ftp.kernel.org/pub/linux/utils/fs/zisofs/


πŸ’Œ MAILING LISTS πŸ’Œ

If you want to actively take part on the development of mkisofs, you may join the developer mailing list via this URL:

https://lists.sourceforge.net/lists/listinfo/cdrtools-developers

come hang out bestie, the group chat is open 🫢


πŸ§‘β€πŸ’» MAINTAINER πŸ§‘β€πŸ’»

Joerg Schilling
Seestr. 110
D-13353 Berlin
Germany

πŸ¦‹ HFS MKHYBRID MAINTAINER πŸ¦‹

James Pearson

j.pearson@ge.ucl.ac.uk

If you have support questions, send them to:

cdrtools-support@lists.sourceforge.net

If you definitely found a bug, send a mail to:

cdrtools-developers@lists.sourceforge.net or joerg.schilling@fokus.fraunhofer.de

To subscribe, use:

https://lists.sourceforge.net/lists/listinfo/cdrtools-developers or https://lists.sourceforge.net/lists/listinfo/cdrtools-support


βš–οΈ INTERFACE STABILITY βš–οΈ

The interfaces provided by mkisofs are designed for long term stability β€” like, they're in it for the long haul, main character energy fr fr. πŸ‘‘

As mkisofs depends on interfaces provided by the underlying operating system, the stability of the interfaces offered by mkisofs depends on the interface stability of the OS interfaces. Modified interfaces in the OS may enforce modified interfaces in mkisofs. So basically, if your OS changes its vibe, mkisofs might have to change its vibe too. That's the deal. πŸ’…


aaaand that's the whole page bestie!! πŸŽ‰ you officially read the entire thing β€” I'm so proud of you πŸ«ΆπŸ’– This was Version 3.02, dated 2017/12/10, from MKISOFS(8). Go make some iconic hybrid discs, and remember: keep every flag, trust no binary file marked 'TEXT', and always give your sessions unique volume names. mwah πŸ’‹βœ¨

πŸ“¦ where this page comes from
  • arch rolling: cdrtools 3.02a09-6 Β· GPL-2.0-or-later AND LGPL-2.1-or-later AND CDDL-1.0
  • πŸ’– girlified by deepseek-ai/DeepSeek-V4.1-Flash-1017 on : a language model's rewrite of the original, under its terms