MOUNT(8)

NAME
mount, umount - mount and dismount file systems

SYNOPSIS
/etc/mount [-afrwuv] [-t vfstype]
/etc/mount [-frwuv] special | node
/etc/mount [-frwu] [-t vfstype] [-o options] special | node
/etc/umount [-a] [-t vfstype]
/etc/umount special | node

DESCRIPTION
The mount command calls the mount(2) system call to prepare and graft a special device on to the file system tree at the point node. If either special or node are not provided, the appropriate information is taken from the fstab(5) file. The special keyword none can be used instead of a path or node specification. This is useful in the case of the proc filesystem.

The system maintains a list of currently mounted file systems. If no arguments are given to mount, this list is printed.

Options available for the mount command:

-f  Causes everything to be done except for the actual system call; if it's not obvious, this ``fakes'' mounting the file system. This option is useful in conjunction with the -v flag to determine what the mount command is trying to do.

-o  Options are specified with a -o flag followed by a comma separated string of options. The following options apply to any file system that is being mounted:

    noexec
        Do not allow execution of any binaries on the mounted file system. This options is useful for a server that has file systems containing binaries for architectures other than its own.

    nosuid
        Do not allow set-user-identifier or set-group-identifier bits to take effect.

    nodev
        Do not interpret character or block special devices on the file system. This options is useful for a server that has file systems containing special devices for architectures other than its own.

    synchronous
        All I/O to the file system should be done synchronously.

-r  The file system object is to be mounted read-only.

-t vfstype
    The argument following the -t is used to indicate the file system type. The file system types which are currently supported are listed in linux/fs/filesystems.c: minux, ext, msdos, proc, nfs, iso9660. The type minix is the default. For example, the mount command:

        mount -a -t nomsdos,ext

    mounts all filesystems except those of type msdos and ext.

-u  The -u flag indicates that the status of an already mounted file system should be changed. Any of the options discussed above (the -o option) may be changed; also a file system can be changed from read-only to read-write. The set of options is determined by first extracting the options for the file system from the fstab table, then applying any options specified by the -o argument, and finally applying the -r or -w option.

-v  Verbose mode.

-w  The file system object is to be read and write.

Umount removes the special device grafted at point node from file system tree.

Options for the umount command:

-a  All of the file systems described in fstab are unmounted.

-t  Is used to indicate the actions should only be taken on filesystems of the specified type. More than one type may be specified in a comma separated list. The list of filesystem types can be prefixed with ``no'' to specify the filesystem types on which no action should be taken. (See example above for the mount command.)

FILES
/etc/fstab
    file system table

SEE ALSO
mount(2), umount(2), fstab(5)

BUGS
It is possible for a corrupted file system to cause a crash.

Linux doesn't support -u or -o synchronous yet.

HISTORY
A mount command appeared in AT&T UNIX.

AUTHORS
The version for 0.97.3 was, apparently, written by Doug Quale (quale@saavik.cs.wisc.edu).
Modified for 0.98.5 by H. J. Lu (hlu@eecs.wsu.edu) on 11/25/92.
Modified for 0.99.2 by Rick Sladkey (jrs@world.std.com)
Modified for 0.99.6 by Rick Sladkey (jrs@world.std.com)