MOUNT_HSFS(1M)MOUNT_HSFS(1M)NAMEmount_hsfs - mount hsfs file systems
mount -F hsfs [generic_options]
[-o FSType-specific_options] [-O ] special | mount_point
mount -F hsfs [generic_options]
[-o FSType-specific_options] [-O] special mount_point
mount attaches an ISO 9660 filesystem (the High Sierra file system,
hsfs, is a draft predecessor to ISO 9660, so the name reflects the
filesystem's history) to the file system hierarchy at the
mount_point, which is the pathname of a directory. If mount_point has
any contents prior to the mount operation, these are hidden until the
file system is unmounted.
If mount is invoked with special or mount_point as the only argu‐
ments, mount will search /etc/vfstab to fill in the missing argu‐
ments, including the FSType-specific_options; see mount(1M) for more
The hsfs file system supports direct mounting of files containing the
file system as well as block devices. See mount(1M) and lofiadm(1M).
A file system conforming to ISO 9660 can contain extensions that allow
it to overcome limitations of the original ISO 9660:1988 (version 1)
standard. The following types of extensions are supported by hsfs:
Rock Ridge extensions
This is the preferred type of extension as it allows file
attributes, name length, and types equivalent to those on other
UNIX-style filesystems. Example of supported features are device
special files, POSIX permissions, symbolic links, and filenames of
up to 255 bytes in length. Rock Ridge extensions also remove the
ISO9660:1988 restriction on maximum nesting depth for directories
(eight levels). hsfs automatically detects the presence of Rock
Ridge extensions and uses them, unless mount options are specified
to disable the use of Rock Ridge or to use a different extension.
ISO9660:1999 (version 2) extensions
The first version of ISO9660, released in 1988, supported only
uppercase ASCII filenames of no more than 31 characters in length.
ISO9660 version 2, released in 1999, provides an extension that
allows filenames of at least 207 bytes that can use UTF-8 charac‐
ters and removes the limitation on the nesting depth for directo‐
ries. Unlike Rock Ridge, it does not provide support for UNIX-
style file types and file attributes. hsfs automatically detects
this extension and will use it for filename lookup if no Rock Ridge
extensions are found on the media.
The Joliet extension was devised by Microsoft to allow Unicode
(UCS-2) long filenames with CDROM-based media. It allows filename
lengths of up to 110 Unicode characters and does not support UNIX-
style file types and attributes. hsfs falls back to using Joliet
if such an extension is present and neither Rock Ridge nor ISO9660
version 2 extensions are found.
If filenames are longer than the 64 UCS-2 characters officially
allowed by Microsoft (that is, 110 Unicode characters), they can
translate to up to 330 UTF-8 octets. Filenames that translate to
more than 255 UTF-8 octets will be truncated.
See mount(1M) for the list of supported options.
Specify hsfs file system specific options. If invalid options are
specified, a warning message is printed and the invalid options are
ignored. The following options are available:
global | noglobal
If global is specified and supported on the file system, and
the system in question is part of a cluster, the file system
will be globally visible on all nodes of the cluster. If
noglobal is specified, the mount will not be globally visible.
The default behavior is noglobal.
Mount the file system read-only. This option is required.
rr | nrr
Enable (rr) or disable (nrr) the use of Rock Ridge. rr is the
default and need not be specified. If you use nrr and Rock
Ridge extensions are present in the file system, ignore them
and search for other available extensions or fall back to plain
vers2 | novers2
Enable or disable the use of ISO9660 version 2 extensions. If
vers2 is specified and ISO9660 version 2 extensions are avail‐
able, hsfs will use ISO9660 version 2 even if the file system
contains the preferred Rock Ridge extensions as well. If
novers2 is specified, it will fall back to using either Joliet
extensions or plain ISO9660 even if ISO9660 version 2 exten‐
sions are available.
joliet | nojoliet
Enable or disable the use of Joliet extensions. If joliet is
specified and Joliet extensions are available, hsfs will use
them even if the file system contains the preferred Rock Ridge
and/or ISO9660 version 2 extensions. If nojoliet is specified,
it will fall back to using plain ISO9660.
File names on High Sierra file systems consist of a proper name
and an extension separated by a '.' (dot) character. By
default, the separating dot is always considered part of the
file's name for all file access operations, even if there is no
extension present. Specifying notraildot makes it optional to
specify the trailing dot to access a file whose name lacks an
Exceptions: This option is effective only on file systems for
which Rock Ridge, ISO9660 version 2 or Joliet extensions are
not active, either because they are not present on the CD-ROM,
or they have been deliberately disabled via the nrr, novers2
and nojoliet option. If either extension is active, hsfs qui‐
etly ignores this option.
File names on High Sierra/ISO9660 CD-ROMs with no extensions
present should be uppercase characters only. By default, hsfs
maps file names read from a non-Rock Ridge disk to all lower‐
case characters. nomaplcase turns off this mapping. The excep‐
tions for notraildot discussed above apply to nomaplcase.
Overlay mount. Allow the file system to be mounted over an exist‐
ing mount point, making the underlying file system inaccessible.
If a mount is attempted on a preexisting mount point without set‐
ting this flag, the mount will fail, producing the error: device
Example 1 Mounting and Unmounting a DVD Image Directly
The following commands mount and unmount a DVD image.
# mount -F hsfs /images/solaris.iso /mnt/solaris-image
# umount /mnt/solaris-image
table of mounted file systems
list of default parameters for each file system
SEE ALSOlofiadm(1M), mount(1M), mountall(1M), mount(2), mnttab(4), vfstab(4),
If the directory on which a file system is to be mounted is a symbolic
link, the file system is mounted on the directory to which the symbolic
link refers, rather than on top of the symbolic link itself.
May 29, 2008 MOUNT_HSFS(1M)