mount_tmpfs(8) - NetBSD Manual Pages

MOUNT_TMPFS(8)          NetBSD System Manager's Manual          MOUNT_TMPFS(8)


NAME

     mount_tmpfs -- mount an efficient memory file system


SYNOPSIS

     mount_tmpfs [-g group] [-m mode] [-n nodes] [-o options] [-s size]
                 [-u user] tmpfs mount_point


DESCRIPTION

     The mount_tmpfs command attaches an instance of the efficient memory file
     system to the global file system namespace.  The directory specified by
     mount_point is converted to an absolute path before use and its
     attributes (owner, group and mode) are inherited unless explicitly over-
     riden by the options described below.

     The following options are supported:

     -g group    Specifies the group name or GID of the root inode of the file
                 system.  Defaults to the mount point's GID.

     -m mode     Specifies the mode (in octal notation) of the root inode of
                 the file system.  Defaults to the mount point's mode.

     -n nodes    Specifies the maximum number of nodes available to the file
                 system.

     -o options  Options are specified with a -o flag followed by a comma-sep-
                 arated string of options.  See the mount(8) man page for pos-
                 sible options and their meanings.

     -s size     Specifies the total file system size in bytes.  If zero is
                 given (the default), the available amount of memory (includ-
                 ing main memory and swap space) will be used.  Note that four
                 megabytes are always reserved for the system and cannot be
                 assigned to the file system.

     -u user     Specifies the user name or UID of the root inode of the file
                 system.  Defaults to the mount point's UID.

     Every option that accepts a numerical value as its argument can take a
     trailing `b' to indicate bytes (the default), a trailing `k' to indicate
     kilobytes, a trailing `M' to indicate megabytes or a trailing `G' to
     indicate gigabytes.  Note that both lowercase and uppercase forms of
     these letters are allowed.


EXAMPLES

     The following command mounts a tmpfs instance over the /tmp directory,
     inheriting its owner, group and mode settings:

     mount -t tmpfs tmpfs /tmp

     The following command mounts a tmpfs instance over the /mnt directory,
     setting a 20 megabytes limit in space, owned by the `joe' user and
     belonging to the `users' group, with a restricted 0700 mode:

     mount -t tmpfs -o -s20M -o -ujoe -o -gusers -o -m0700 tmpfs /mnt

     See /usr/share/examples/fstab/fstab.ramdisk for some examples on how to
     add tmpfs entries to /etc/fstab.


SEE ALSO

     fstab(5), mount(8)


HISTORY

     The mount_tmpfs utility first appeared in NetBSD 4.0.

NetBSD 4.0                     November 11, 2006                    NetBSD 4.0