freebsd-skq/sbin/umount/umount.8
bde f96e3b64ac Merge from Lite2.
- use new getvfsbyname() interface.
- new -A option, like -a except only mounted file systems are unmounted.

All non-cosmetic FreeBSD changes in umount.c, except ignoring of
realpath() failures, went away because they are done better in Lite2.
realpath() failures must be ignored so that non-pathnames like
"<above>:/foo" and "host:/bar" get as far as mount(2).

Reviewed by:	dfr
1997-06-16 11:20:05 +00:00

149 lines
4.2 KiB
Groff

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.\" @(#)umount.8 8.2 (Berkeley) 5/8/95
.\"
.Dd May 8, 1995
.Dt UMOUNT 8
.Os BSD 4
.Sh NAME
.Nm umount
.Nd unmount filesystems
.Sh SYNOPSIS
.Nm umount
.Op Fl fv
.Ar special | node
.Nm umount
.Fl a | A
.Op Fl fv
.Op Fl h Ar host
.Op Fl t Ar type
.Sh DESCRIPTION
The
.Nm umount
command
calls the
.Xr unmount 2
system call to remove a
.Ar "special device"
or the remote node (rhost:path) from the filesystem tree at the point
.Ar node .
If either
.Ar special
or
.Ar node
are not provided, the appropriate information is taken from the
.Xr fstab 5
file.
.Pp
The options are as follows:
.Bl -tag -width indent
.It Fl a
All the filesystems described in
.Xr fstab 5
are unmounted.
.It Fl A
All the currently mounted filesystems except
the root are unmounted.
.It Fl f
The filesystem is forcibly unmounted.
Active special devices continue to work,
but all other files return errors if further accesses are attempted.
The root filesystem cannot be forcibly unmounted.
.It Fl h Ar host
Only filesystems mounted from the specified host will be
unmounted.
This option is implies the
.Fl A
option and, unless otherwise specified with the
.Fl t
option, will only unmount NFS filesystems.
.It Fl t Ar type
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
.Dq no
to specify the filesystem types for which action should
.Em not
be taken.
For example, the
.Nm umount
command:
.Bd -literal -offset indent
umount -a -t nfs,mfs
.Ed
.Pp
umounts all filesystems of the type
.Tn NFS
and
.Tn MFS .
.It Fl v
Verbose, additional information is printed out as each filesystem
is unmounted.
.El
.Sh FILES
.Bl -tag -width /etc/fstab -compact
.It Pa /etc/fstab
filesystem table
.El
.Sh SEE ALSO
.Xr unmount 2 ,
.Xr fstab 5 ,
.Xr mount 8
.Sh BUGS
When using union filesystems,
.Xr umount 8
cannot always determine the node which is the mountpoint.
In this case,
it is necessary to specify the relevant directory to be unmounted
in the same form as that displayed by
.Xr mount 8 .
For example, given a mount entry like this:
.Bd -literal -offset indent
<above>/tmpdir on /cdrom (local, user mount)
.Ed
.Pp
then the command:
.Bd -literal -offset indent
umount '<above>/tmpdir'
.Ed
.Pp
would unmount
.Ar /tmpdir
from the mountpoint
.Ar /cdrom .
.Sh HISTORY
A
.Nm umount
command appeared in
.At v6 .