MOUNT_TMPFS(8) Maintenance Commands and Procedures MOUNT_TMPFS(8)

NAME

mount_tmpfs - mount tmpfs file systems

SYNOPSIS

mount [-F tmpfs] [-o specific_options] [-O] special mount_point

DESCRIPTION

tmpfs is a memory based file system which uses kernel resources
relating to the VM system and page cache as a file system.


mount attaches a tmpfs file system to the file system hierarchy at
the pathname location mount_point, which must already exist. If
mount_point has any contents prior to the mount operation, these
remain hidden until the file system is once again unmounted. The
attributes (mode, owner, and group) of the root of the tmpfs
filesystem are inherited from the underlying mount_point, provided
that those attributes are determinable. If not, the root's attributes
are set to their default values. The mode may also be overridden by
the mode mount option, which takes precedence if set.


The special argument is usually specified as swap but is in fact
disregarded and assumed to be the virtual memory resources within the
system.

OPTIONS

-o specific_options
Specify tmpfs file system specific options in
a comma-separated list with no intervening
spaces. If invalid options are specified, a
warning message is printed and the invalid
options are ignored. The following options are
available:

remount

Remounts a file system with
a new size. A size not
explicitly set with remount
reverts to no limit.


mode=octalmode
The mode argument controls
the permissions of the
tmpfs mount point. The
argument must be an octal
number, of the form passed
to chmod(1). Only the
access mode, setuid,
setgid, and sticky bits (a
mask of 07777) may be set.
If this option is not
provided then the default
mode behaviour, as
described above, applies.


size=sz
The sz argument controls
the size of this particular
tmpfs file system. If the
argument is has a `k'
suffix, the number will be
interpreted as a number of
kilobytes. An `m' suffix
will be interpreted as a
number of megabytes. A `g'
suffix will be interpreted
as a number of gigabytes. A
`%' suffix will be
interpreted as a percentage
of the swap space available
to the zone. No suffix is
interpreted as bytes. In
all cases, the actual size
of the file system is the
number of bytes specified,
rounded up to the physical
pagesize of the system.


xattr | noxattr
Allow or disallow the
creation and manipulation
of extended attributes. The
default is xattr. See
fsattr(7) for a description
of extended attributes.


-O
Overlay mount. Allow the file system to be
mounted over an existing mount point, making
the underlying file system inaccessible. If a
mount is attempted on a pre-existing mount
point without setting this flag, the mount
will fail, producing the error: device busy.

FILES

/etc/mnttab
Table of mounted file systems

SEE ALSO

mkdir(2), mount(2), open(2), umount(2), tmpfs(4FS), mnttab(5),
attributes(7), fsattr(7), mount(8)

NOTES

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.

March 18, 2015 MOUNT_TMPFS(8)