Tribblix: manual page: hsfs.4fs

HSFS(4FS) File Systems HSFS(4FS)

NAME

hsfs - High Sierra & ISO 9660 CD-ROM file system

DESCRIPTION

hsfs is a file system type that allows users to access files on High
Sierra or ISO 9660 format CD-ROM disks from within the SunOS operating
system. Once mounted, a hsfs file system provides standard read-only
file system operations and semantics, meaning that you can read and
list files in a directory on a High Sierra or ISO 9660 CD-ROM and
applications can use standard UNIX system calls on these files and
directories.

This file system contains support for Rock Ridge, ISO 9660 Version 2
and Joliet extensions. These extensions provide support for file names
with a length of at least 207 bytes, but only Rock Ridge extensions
(with the exception of writability and hard links) can provide file
system semantics and file types as they are found in UFS. The presence
of Rock Ridge, ISO 9660 Version 2, and Joliet is autodetected and the
best-suitable available extension is used by the HSFS driver for file
name and attribute lookup.

If your /etc/vfstab file contains a line similar to the following:

/dev/dsk/c0t6d0s0 - /hsfs hsfs - no ro

and /hsfs exists, you can mount an hsfs file system with either of the
following commands:

mount -F hsfs -o ro device-special directory-name
or

mount /hsfs

By default, Rock Ridge extensions are used if available, otherwise ISO
9660 Version 2, then Joliet are used. If neither extension is present
HSFS defaults to the standard capabilities of ISO 9660. Since so-
called hybrid CD-ROMs that contain multiple extensions are possible,
you can use the following mount options to deliberately disable the
search for a specific extension or to force the use of a specific
extension even if a preferable type is present:

mount -F hsfs -o ro,nrr device-special directory-name

Mount options are:

rr Request HSFS to use Rock Ridge extensions, if present. This is
the default behavior and does not need to be explicitly
specified.

nrr Disable detection and use of Rock Ridge extensions, even if
present.

vers2 Request HSFS to use ISO 9660 Version 2 extensions, even if Rock
Ridge is available.

novers2
Disable detection and use of ISO 9660 Version 2 extensions.

joliet Request HSFS to use Joliet extensions, even if Rock Ridge or
ISO 9660 Version 2 extensions are available.

nojoliet
Disable detection and use of Joliet extensions.

Files on a High Sierra or ISO 9660 CD-ROM disk have names of the form
filename.ext;versio, where filename and the optional ext consist of a
sequence of uppercase alphanumeric characters (including `_'), while
the version consists of a sequence of digits, representing the version
number of the file. hsfs converts all the uppercase characters in a
file name to lowercase, and truncates the `'; and version information.
If more than one version of a file is present on the CD-ROM, only the
file with the highest version number is accessible.

Conversion of uppercase to lowercase characters may be disabled by
using the -o nomaplcase option to mount(8). See mount_hsfs(8).

If the CD-ROM contains Rock Ridge, ISO 9660 version 2 or Joliet
extensions, the file names and directory names may contain any
character supported under ufs(4FS). The names may also be upper and/or
lower case and are case sensitive. File name lengths can be as long as
those of ufs(4FS).

Files accessed through hsfs have mode 555 (owner, group and world
readable and executable), uid 0 and gid 3. If a directory on the CD-ROM
has read permission, hsfs grants execute permission to the directory,
allowing it to be searched.

With Rock Ridge extensions, files and directories can have any
permissions that are supported on a ufs(4FS) file system. However,
under all write permissions, the file system is read-only, with EROFS
returned to any write operations.

Like High Sierra and ISO 9660 CD-ROMs, HSFS supports only regular files
and directories. A Rock Ridge CD-ROM can support regular files,
directories, and symbolic links, as well as device nodes, such as
block, character, and FIFO.

EXAMPLES

Example 1 Sample Display of File System Files

If there is a file BIG.BAR on a High Sierra or ISO 9660 format CD-ROM
it will show up as big.bar when listed on a hsfs file system.

If there are three files Pa BAR.BAZ;1 , Pa BBAR.BAZ;2 , and BAR.BAZ;3
on a High Sierra or ISO 9660 format CD-ROM, only the file BAR.BAZ;3
will be accessible. It will be listed as bar.baz.

DIAGNOSTICS

hsfs: Warning: the file system... does not conform to the ISO-9660
spec
The specific reason appears on the following line. You might
be attempting to mount a CD-ROM containing a different file
system, such as ufs(4FS)

hsfs: Warning: the file system... contains a file [with an] unsupported
type" The hsfs file system does not support the format of some
file or directory on the CD-ROM, for example a record
structured file.

hsfs: hsnode table full, %d nodes allocated
There are not enough hsfs internal data structure elements to
handle all the files currently open. This problem may be
overcome by adding a line of the form `set hsfs:nhsnode=number'
to the /etc/system system configuration file and rebooting.
See system(5).

WARNINGS

Do not physically eject a CD-ROM while the device is still mounted as a
hsfs file system.

Under MS-DOS (for which CD-ROMs are frequently targeted), files with no
extension may be represented either as: filename. or filename that is,
with or without a trailing period. These names are not equivalent
under UNIX systems. For example, the names: BAR. and BAR are not names
for the same file under the UNIX system. This may cause confusion if
you are consulting documentation for CD-ROMs originally intended for
MS-DOS systems.

Use of the -o notraildot option to mount(8) makes it optional to
specify the trailing dot. See mount_hsfs(8).

NOTES