NAME
mkhybrid - create an hybrid ISO9660/JOLIET/HFS filesystem
with optional Rock Ridge attributes.
SYNOPSIS
mkhybrid [ -a ] [ -b boot_image ] [ -c boot_catalog ] [ -A
application_id ] [ -f ] [ -d ] [ -D ] [ -hide glob ] [
-hide-joliet glob ] [ -J ] [ -l ] [ -L ] [ -no-split-
symlink-components ] [ -no-split-symlink-fields ] [ -p
preparer ] [ -print-size ] [ -P publisher ] [ -quiet ] [ -r
] [ -R ] [ -T | -table-name TABLE_NAME ] [ -v ] [ -V volid ]
[ -x path ] [ -z ] [ -m glob ] [ -hfs | -apple ] [ -map
mapping_file ] [ -magic magic_file ] [ -no-mac-files ] [
-probe ] [ --cap ] [ --netatalk ] [ --double ] [ --
ethershare ] [ --ushare ] [ --exchange ] [ --sgi ] [ --xinet
] [ --macbin ] [ --single ] [ -no-desktop ] [ -mac-name ] [
-boot-hfs-file driver_file ] [ -hide-hfs glob ] [ -log-file
log_file ] -o filename pathspec [pathspec]
DESCRIPTION
mkhybrid is effectively a pre-mastering program to generate
an HFS/ISO9660/JOLIET hybrid filesystem. It is based on
mkisofs(1) and will generate a pure ISO9660 filesystem
unless the HFS hybrid command line options are given.
mkhybrid can generate a true (or shared) HFS hybrid filesys-
tem. The same files are seen as HFS files when accessed from
a Macintosh and as ISO9660 files when accessed from other
machines. HFS stands for Hierarchical File System and is the
native file system used on Macintosh computers.
As an alternative, mkhybrid can generate the Apple Enten-
sions to ISO9660 for each file. These extensions provide
each file with CREATOR, TYPE and certain Finder Flags when
accessed from a Macintosh. See the MACINTOSH FILE FORMATS
section below.
mkhybrid takes a snapshot of a given directory tree, and
generates a binary image which will correspond to an ISO9660
or HFS filesystem when written to a block device.
mkhybrid is also capable of generating the System Use Shar-
ing Protocol records specified by the Rock Ridge Interchange
Protocol. This is used to further describe the files in the
iso9660 filesystem to a unix host, and provides information
such as longer filenames, uid/gid, posix permissions, and
block and character devices.
Each file written to the iso9660 filesystem must have a
filename in the 8.3 format (8 characters, period, 3 charac-
ters, all upper case), even if Rock Ridge is 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. mkhybrid 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 trun-
cated names are not all unique. mkhybrid 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~ - the file foo.bar.~1~
would be written as FOO.000;1 and the file foo.bar would be
written as FOO.BAR;1
When used with the HFS options, mkhybrid will attempt to
recognise files stored in a number of Apple/Unix file for-
mats and will copy the data and resource forks as well as
any relevant finder information. See the MACINTOSH FILE FOR-
MATS section below for more about formats mkhybrid supports.
Note that mkhybrid is not designed to communicate with the
writer directly. Most writers have proprietary command sets
which vary from one manufacturer to another, and you need a
specialized tool to actually burn the disk. The cdwrite
utility is one such tool that runs under Linux and performs
this task. The latest version of cdwrite is capable of com-
municating with Phillips/IMS/Kodak, HP and Yamaha drives.
Most writers come with some version of DOS software that
allows a direct image copy of an iso9660 image to the
writer. The current version of cdwrite is available from
sunsite.unc.edu: /utils/disk-management/cdwrite-2.0.tar.gz
Note that cdwrite has not been actively maintained in recent
times.
The cdrecord utility is another utility capable of burning
an actual disc. The latest version of cdrecord is available
from ftp://ftp.fokus.gmd.de/pub/unix/cdrecord
Also you should know that most cd writers are very particu-
lar 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.
path is the path of the directory tree to be copied into the
iso9660 filesystem. Multiple paths can be specified, and
mkhybrid will merge the files found in all of the specified
path components to form the cdrom image.
It is possible to graft the paths at points other than the
root directory, and it is possible to graft files or direc-
tories 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. mkhybrid will create any directories
required such that the graft points exist on the cdrom image
- the directories do not need to appear in one of the paths.
Any directories that are created on the fly like this will
have permissions 0555 and appear to be owned by the person
running mkhybrid. If you wish other permissions or owners
of the intermediate directories, the easiest solution is to
create real directories in the path such that mkhybrid
doesn't have to invent them.
mkhybrid will also run on Win95/NT4 machines when compiled
with Cygnus' GNU-Win32 (available from
http://www.cygnus.com/misc/gnu-win32/). Therefore most
references in this man page to Unix can be replaced with
Win32.
OPTIONS
-a Include all files on the iso9660 filesystem. Normally
files that contain the characters '~' or '#' will not
be included (these are typically backup files for edi-
tors under unix).
-A application_id
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. This parameter can
also be set in the file .mkisofsrc with APPI=id. If
specified in both places, the command line version is
used.
-b boot_image
Specifies the path and filename of the boot image to be
used when making an "El Torito" bootable CD. The path-
name must be relative to the source path specified to
mkhybrid. This option is required to make a bootable
CD. The boot image must be exactly the size of either
a 1.2, 1.44, or a 2.88 meg floppy, and mkhybrid will
use this size when creating the output iso9660 filesys-
tem. It is assumed that the first 512 byte sector
should be read from the boot image (it is essentially
emulating a normal floppy drive). This will work, for
example, if the boot image is a LILO based boot floppy.
-c boot_catalog
Specifies the path and filename of the boot catalog to
be used when making an "El Torito" bootable CD. The
pathname must be relative to the source path specified
to mkhybrid. This option is required to make a bootable
CD. This file will be created by mkhybrid in the
source filesystem, so be sure the specified filename
does not conflict with an existing file, as it will be
quietly overwritten! Usually a name like "boot.catalog"
is chosen.
-d Omit trailing period from files that do not have a
period. This violates the ISO9660 standard, but it
happens to work on many systems. Use with caution.
-D Do not use deep directory relocation, and instead just
pack them in the way we see them. This violates the
ISO9660 standard, but it works on many systems. Use
with caution.
-f Follow 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.
-hide glob
Hide glob from being seen on the ISO9660 or Rock Ridge
directory. glob is a shell wild-card-style pattern
that must match any part of the filename or path. Mul-
tiple globs may be hidden (up to 1000). If glob
matches a directory, then the contents of that direc-
tory will be hidden. All the hidden files will still
be written to the output CD image file. Should be used
with the -hide-joliet option.
-hide-joliet glob
Hide 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 (up to 1000). If glob matches a directory,
then the contents of that directory will be hidden.
All the hidden files will still be written to the out-
put CD image file. Should be used with the -hide
option.
-l Allow full 32 character filenames. Normally the
ISO9660 filename will be in an 8.3 format which is com-
patible with MS-DOS, even though the ISO9660 standard
allows filenames of up to 32 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 sys-
tems (such as the Amiga). Use with caution.
-J Generate Joliet directory records in addition to regu-
lar iso9660 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.
-L Allow filenames to begin with a period. Usually, a
leading dot is replaced with an underscore in order to
maintain MS-DOS compatibility.
-m glob
Exclude glob from being written to CDROM. glob is a
shell wild-card-style pattern that must match part of
the filename (not the path as with option -x). Techni-
cally glob is matched against the d->d_name part of the
directory entry. Multiple globs may be excluded (up to
1000). Example:
mkhybrid -o rom -m '*.o' -m core -m foobar
would exclude all files ending in ".o", called "core"
or "foobar" to be copied to CDROM. Note that if you had
a directory called "foobar" it too (and of course all
its descendants) would be excluded.
-M path
Specifies path to existing iso9660 image to be merged.
The output of mkhybrid 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 are attempt-
ing to write this image to. Support for this is not
yet 100% complete, because some handshaking is required
between mkhybrid and cdwrite in order to determine the
next writable address on the cdrom.
-N Omit version numbers from ISO9660 file names. This may
violate the ISO9660 standard, but no one really uses
the version numbers anyway. Use with caution.
-no-split-symlink-components
Don't split the SL components, but begin a new Con-
tinuation 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).
-no-split-symlink-fields
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).
-o filename
is the name of the file to which the iso9660 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.
-P publisher_id
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 is space on the disc for 128 characters
of information. This parameter can also be set in the
file .mkisofsrc with PUBL=. If specified in both
places, the command line version is used.
-p preparer_id
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 is space on the disc for 128 characters
of information. This parameter can also be set in the
file .mkisofsrc with PREP=. If specified in both
places, the command line version is used.
-print-size
Print estimated filesystem size and exit. This option
is needed for Disk At Once mode and with some CD-R
drives when piping directly into cdrecord. In this case
it is needed to know the size of the filesystem before
the actual CD-creation is done. The option -print-size
allows to get this size from a "dry-run" before the CD
is actually written.
-R Generate SUSP and RR records using the Rock Ridge pro-
tocol to further describe the files on the iso9660
filesystem.
-r This is like the -R option, but file ownership and
modes are set to more useful values. The uid and gid
are set to zero, because they are usually only useful
on the author's system, and not useful to the client.
All the file read bits are set true, so that files and
directories are globally readable on the client. If
any execute bit is set for a file, set all of the exe-
cute bits, so that executables are globally executable
on the client. If any search bit is set for a direc-
tory, set all of the search bits, so that directories
are globally searchable on the client. All write bits
are cleared, because the CD-Rom will be mounted read-
only in any case. If any of the special mode bits are
set, clear them, because file locks are not useful on a
read-only file system, and set-id bits are not desir-
able for uid 0 or gid 0. When used on Win32, the exe-
cute bit is set on all files.
-T Generate a file TRANS.TBL in each directory on the
CDROM, which can be used on non-Rock Ridge capable sys-
tems 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.
-table-name TABLE_NAME
Alternative translation table file name (see above).
Implies the -T option.
-V volid
Specifies the volume ID (volume name or label) to be
written into the master block. This parameter can also
be set in the file .mkisofsrc with VOLI=id. If speci-
fied in both places, the command line version is used.
-v Verbose execution.
-x path
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 (up to 1000). Example:
mkhybrid -o cd -x /local/dir1 -x /local/dir2 /local
-z Generate special SUSP records for transparently
compressed files. This is only of use and interest for
hosts that support transparent decompression. This is
an experimental feature, and no hosts yet support this,
but there are ALPHA patches for Linux that can make use
of this feature.
HFS OPTIONS
-hfs Create an ISO9660/HFS hybrid CD. By default, all source
files are checked to attempt to recognise files stored
in one of the known Apple/Unix file formats. See the
MACINTOSH FILE FORMATS section below for more about
these formats
-apple
Create an ISO9660 CD with Apple's extensions. Similar
to the -hfs option, except that the Apple Extensions to
ISO9660 are added instead of creating an HFS hybrid
volume.
-map mapping_file
Use the mapping_file to set the CREATOR and TYPE infor-
mation for a file based on the filename's extension. A
filename is mapped only if it is not one of the know
Apple/Unix file formats. See the CREATOR/TYPE section
below.
-magic magic_file
The CREATOR and TYPE information is set by using a
file's magic number (usually the first few bytes of a
file). The magic_file is only used if a file is not one
of the known Apple/Unix file formats, or the filename
extension has not been mapped using the -map option.
See the CREATOR/TYPE section below for more details.
-no-mac-files
Disables searching for Apple/Unix files. This will
speed up processing if there are none of the known
Apple/Unix format files in the source directory trees
(the source directories just contain ordinary files).
The -map and/or -magic option can be used to set the
CREATOR and TYPE for each file.
-probe
Search the contents of files for Apple/Unix file for-
mats. When -hfs or -apple is used, mkhybrid will
attempt to work out automatically what type of
Apple/Unix format each file is. However, the only way
to check for MacBinary and AppleSingle files is to open
and read them. Therefore, if MacBinary or AppleSingle
format files are being used, then you need to give this
option. This saves opening and searching every file if
no MacBinary and/or AppleSingle files exist. Or you
could use the relevant double dash options given below.
--cap
Look for AUFS CAP Macintosh files. Search 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.
--netatalk
Look for NETATALK Macintosh files
--double
Look for AppleDouble Macintosh files
--ethershare
Look for Helios EtherShare Macintosh files
--ushare
Look for IPT UShare Macintosh files
--exchange
Look for PC Exchange Macintosh files
--sgi
Look for SGI Macintosh files
--xinet
Look for XINET Macintosh files
--macbin
Look for MacBinary Macintosh files
--single
Look for AppleSingle Macintosh files
-no-desktop
Do not create (empty) Desktop files. New HFS Desktop
files will be created when the CD is used on a Macin-
tosh (and stored in the System Folder). By default,
empty Desktop files are added to the HFS volume.
-mac-name
Use the HFS filename as the starting point for the
ISO9660, Joliet and Rock Ridge file names. See the
MACINTOSH FILE NAMES section below for more informa-
tion.
-boot-hfs-file driver_file
Installs the driver_file that may make the CD bootable
on a Macintosh. See the HFS BOOT DRIVER section below.
-hide-hfs glob
Hide glob from the HFS volume. The file or directory
will still exist in the ISO9660 and/or Joliet
directory. glob is a shell wild-card-style pattern
that must match any part of the filename Multiple globs
may be excluded (up to 1000). Example:
mkhybrid -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:
mkhybrid -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.
-log-file log_file
Redirect all error, warning and informational messages
to log_file instead of the standard error.
CREATOR/TYPE
A Macintosh file has two properties associated with it which
define which application created the file, the CREATOR and
what data the file contains, the TYPE. Both are (exactly) 4
letter strings. Usually this allows a Macintosh user to
double-click on a file and launch the correct application
etc. The CREATOR and TYPE of a particular file can be found
by using something like ResEdit (or similar) on a Macintosh.
The CREATOR and TYPE information is stored in all the vari-
ous Apple/Unix encoded files. For other files it is possi-
ble to 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 these options are given,
then their order on the command line is important. If the -
map option is given first, then a filename extension match
is attempted before a magic number match. However, if the -
magic option is given 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, 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 exten-
sion 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
mkhybrid, but is kept to be compatible with aufs(1).
Although mkhybrid does not alter the contents of a
file, if a binary file has it's 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 - it is
ignored by mkhybrid, 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 - the rou-
tines 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 37235 LZIV ZIVU standard unix compress
0 string 37213 GNUz ZIVU gzip compressed data
0 string %! ASPS TEXT Postscript
0 string 04%! 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 - white space is optional between them. Any other char-
acters on this line are ignored. Continuation lines (start-
ing with a '>') are also ignored i.e. only the initial
offset lines are used.
Using the -magic option may significantly increase process-
ing time as each file has to opened and read to find it's
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.
If the 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
file name 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
MACINTOSH FILE FORMATS
Macintosh files have two parts called the Data and Resource
fork. Either may be empty. Unix (and many other OSs) can
only cope with files having one part (or fork). To add to
this, Macintosh files have a number of attributes associated
with them - probably the most important are the TYPE and
CREATOR. Again Unix has no concept of these types of attri-
butes.
Therefore to store a Macintosh file on a Unix filesystem, a
way has to be found to cope with the two forks and the extra
attributes (which are referred to as the finder info).
Unfortunately, it seems that every software package that
stores Macintosh files on Unix has chosen a completely dif-
ferent storage method.
The Apple/Unix formats that mkhybrid (partially) supports
are:
CAP AUFS format
Data fork stored in file. Resource fork in subdirectory
.resource with same filename as data fork. Finder info
in .finderinfo subdirectory with same filename.
AppleDouble/Netatalk
Data fork stored in file. Resource fork stored in 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
Data structures similar to above, except both forks and
finder info are stored in one file.
Helios EtherShare
Data fork stored in file. Resource fork and finder info
together in subdirectory .rsrc with same filename as
data fork.
IPT UShare
Very similar to the EtherShare format, but the finder
info is stored slightly differently.
MacBinary
Both forks and finder info stored in one file.
Apple PC Exchange
Used by Macintoshes to store Apple files on DOS (FAT)
disks. Data fork stored in file. Resource fork in sub-
directory 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: files must be accessed directly from the DOS
media as mkhybrid needs to find out the native FAT
cluster size. Therefore this may not work if the files
are copied to other disks before running mkhybrid.
SGI/XINET
Used by SGI machines when they mount HFS disks. Data
fork stored in file. Resource fork in subdirectory
.HSResource with same name. Finder info as one record
in file .HSancillary. Separate .HSancillary for each
data fork directory.
mkhybrid 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 - see the MACINTOSH FILE NAMES section below.
When using the -apple option, the TYPE and CREATOR are
stored in the optional System Use or SUSP field in the
ISO9660 Directory Record - 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).
The Apple extensions require the resource fork to be stored
as an ISO9660 associated file. This is just like any normal
file stored in the ISO9660 filesystem except that the asso-
ciated 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 ISO9660 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
ISO9660 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 - important when the total size of the
source files is approaching 650MB.
MACINTOSH FILE NAMES
Where possible, the HFS filename that is stored with an
Apple/Unix file is used for the HFS part of the CD. However,
not all the Apple/Unix encodings store the HFS filename with
the finderinfo. In these cases, the Unix filename is used -
with escaped special characters. Special characters include
'/' and characters with codes over 127.
Aufs escapes these characters by using ":" followed by the
character code as two hex digits. Netatalk and EtherShare
has a similar scheme, but uses "%" instead of a ":".
If mkhybrid 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 -
although any remaining ":" is converted to "%" as colon is
the HFS directory separator. Care must be taken, as an ordi-
nary 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 mkhybrid will
attempt, where possible, to make a unique name by adding '_'
characters to one of the filenames.
If an HFS filename exists for a file, then mkhybrid can use
this name as the starting point for the ISO9660, Joliet and
Rock Ridge filenames using the -mac-name option. 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 mkhybrid uses
the Unix name as the starting point for the other names,
then the ISO9660 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 ISO9660 name will probably be
SOMEIMAG.GIF and the Joliet/Rock Ridge would be
someimage.gif.
Using the -mac-name option will not currently work with the
-T option - the Unix name will be used in the TRANS.TBL
file, not the Macintosh name.
The existing mkisofs code will filter out any illegal char-
acters for the ISO9660 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 coverts '/' to a
'_' in a Rock Ridge filenames.
If the Apple extensions are used, then only the ISO9660
filenames will appear on the Macintosh. However, as the
Macintosh ISO9660 drivers can use Level 2 filenames, then
you can use the -l option without problems on a Macintosh -
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 -
don't know if this is a Macintosh problem or
mkisofs/mkhybrid problem. All filenames will be in uppercase
when viewed on a Macintosh. Of course, DOS/Win3.X machines
will not be able to see Level 2 filenames...
HFS BOOT DRIVER
It may be possible to make the hybrid CD bootable on a
Macintosh.
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.
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 it's boot block
set. The boot block is in the first two blocks of a parti-
tion. 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 - unfortunately I don't know the full
spec for the boot block, so I'm guessing that the following
will work OK.
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
mkhybrid.
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.
CONFIGURATION
mkhybrid looks for the .mkisofsrc file, first in the current
working directory, then in the user's home directory, and
then in the directory in which the mkhybrid 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.
Some fields in the volume header are not settable on the
command line, but can be altered through this facility.
Comments may be placed in this file, using lines which start
with a hash (#) character.
APPI The application identifier should describe the applica-
tion that will be on the disc. There is space on the
disc for 128 characters of information. May be over-
ridden using the -A command line option.
COPY 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.
ABST 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.
BIBL 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.
PREP 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.
May be overridden using the -p command line option.
PUBL This should describe the publisher of the CDROM, usu-
ally with a mailing address and phone number. There is
space on the disc for 128 characters of information.
May be overridden using the -P command line option.
SYSI The System Identifier. There is space on the disc for
32 characters of information.
VOLI The Volume Identifier. There is space on the disc for
32 characters of information. May be overridden using
the -V command line option.
VOLS The Volume Set Name. There is space on the disc for
278 characters of information.
TYPE The default TYPE for Macintosh files. Must be exactly 4
characters.
CREATOR
The default CREATOR for Macintosh files. Must be
exactly 4 characters.
mkhybrid can also be configured at compile time with
defaults for many of these fields. See the file defaults.h.
AUTHOR
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 iso9660 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.
Eric Youngdale <ericy@gnu.ai.mit.edu> or
<eric@andante.jic.com> wrote both the Linux isofs9660
filesystem and the mkisofs utility, and is currently main-
taining them. The copyright for the mkisofs utility is held
by Yggdrasil Computing, Incorporated.
mkhybrid is based on mkisofs and works in exactly the same
way as mkisofs without the HFS options. The change in name
is to signify that it does something extra. If you do not
need the HFS options, then you should really be using
mkisofs.
HFS hybrid code Copyright (C) James Pearson 1997, 1998
libhfs code Copyright (C) 1996, 1997 Robert Leslie
libfile code Copyright (C) Ian F. Darwin 1986, 1987, 1989,
1990, 1991, 1992, 1994, 1995.
BUGS
Any files that have hard links to files not in the tree
being copied to the iso9660 filesystem will have an
incorrect file reference count.
There may be some other ones. Please, report them to the
author.
HFS PROBLEMS/LIMITATIONS
I have had to make several assumptions on how I expect the
modified libhfs routines to work, however there may be
situations that either I haven't thought of, or come across
when these assumptions fail. Therefore I can't guarantee
that mkhybrid will work as expected (although I haven't had
a major problem yet).
Output volume size must be at least 800Kb (libhfs limit -
shouldn't really be a problem).
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 mkhybrid will
attempt, where possible, to make a unique name by adding '_'
characters to one of the filenames.
HFS file/directory names that share the first 31 characters
have _N' (N == decimal number) substituted for the last few
characters to generate unique names.
Care must be taken when "grafting" Apple/Unix files or
directories (see above for the method and syntax involved).
It is not possible to use a new name for an Apple/Unix
encoded file/directory. e.g. If a Apple/Unix encoded file
called "oldname" is to added to the CD, then you can not use
the command line:
mkhybrid -o output.raw -hfs newname=oldname cd_dir
mkhybrid will be unable to decode "oldname". However, you
can graft Apple/Unix encoded files or directories as long as
you do not atempt to give them new names as above.
The -M option has no real meaning with an HFS volume - and
will probably not work.
Symbolic links (as with all other non-regular files) are not
added to the HFS directory.
Hybrid volumes may be larger than pure ISO9660 volumes con-
taining the same data.
The resulting hybrid volume can be accessed on a Unix
machine by using the hfsutils routines. However, no changes
should be made to the contents of the volume as it's not a
"real" HFS volume.
Using the -mac-name option will not currently work with the
-T option - the Unix name will be used in the TRANS.TBL
file, not the Macintosh name.
Although mkhybrid does not alter the contents of a file, if
a binary file has it's TYPE set as 'TEXT', it may be read
incorrectly on a Macintosh. Therefore a better choice for
the default TYPE may be '????'
The -mac-boot-file option may not work at all...
SEE ALSO
mkisofs(8), magic(5), apple_driver(8)
FUTURE IMPROVEMENTS
Some sort of gui interface.
AVAILABILITY
mkisofs is available for anonymous ftp from tsx-11.mit.edu
in /pub/linux/packages/mkisofs and many other mirror sites.
mkhybrid is available from ftp://ftp.ge.ucl.ac.uk/pub/mkhfs
and hfsutils from ftp://ftp.mars.org/pub/hfs