xref: /netbsd-src/sbin/umount/umount.8 (revision 326b2259b73e878289ebd80cd9d20bc5aee35e99)
1.\"	$NetBSD: umount.8,v 1.11 2003/08/07 10:04:41 agc Exp $
2.\"
3.\" Copyright (c) 1980, 1989, 1991, 1993
4.\"	The Regents of the University of California.  All rights reserved.
5.\"
6.\" Redistribution and use in source and binary forms, with or without
7.\" modification, are permitted provided that the following conditions
8.\" are met:
9.\" 1. Redistributions of source code must retain the above copyright
10.\"    notice, this list of conditions and the following disclaimer.
11.\" 2. Redistributions in binary form must reproduce the above copyright
12.\"    notice, this list of conditions and the following disclaimer in the
13.\"    documentation and/or other materials provided with the distribution.
14.\" 3. Neither the name of the University nor the names of its contributors
15.\"    may be used to endorse or promote products derived from this software
16.\"    without specific prior written permission.
17.\"
18.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28.\" SUCH DAMAGE.
29.\"
30.\"     @(#)umount.8	8.2 (Berkeley) 5/8/95
31.\"
32.Dd May 8, 1995
33.Dt UMOUNT 8
34.Os
35.Sh NAME
36.Nm umount
37.Nd unmount filesystems
38.Sh SYNOPSIS
39.Nm
40.Op Fl fvFR
41.Ar special | node
42.Nm
43.Fl a | A
44.Op Fl fvFR
45.Op Fl h Ar host
46.Op Fl t Ar type
47.Sh DESCRIPTION
48The
49.Nm
50command
51calls the
52.Xr unmount 2
53system call to remove a
54.Ar "special device"
55or the remote node (rhost:path) from the filesystem tree at the point
56.Ar node .
57If either
58.Ar special
59or
60.Ar node
61are not provided, the appropriate information is taken from the
62.Xr fstab 5
63file.
64.Pp
65The options are as follows:
66.Bl -tag -width indent
67.It Fl a
68All the currently mounted filesystems except the root are unmounted.
69.It Fl A
70Synonym for
71.Fl a .
72.It Fl f
73The filesystem is forcibly unmounted.
74Active special devices continue to work,
75but all other files return errors if further accesses are attempted.
76The root filesystem cannot be forcibly unmounted.
77.It Fl F
78Fake the unmount; perform all other processing but do not actually
79attempt the unmount.
80(This is most useful in conjunction with
81.Fl v ,
82to see what
83.Nm
84would attempt to do).
85.It Fl R
86Take the
87.Ar special | node
88argument as a path to be passed directly to
89.Xr unmount 2 ,
90bypassing all attempts to be smart about mechanically determining the
91correct path from the argument.
92This option is incompatible with any option that potentially umounts
93more than one filesystem, such as
94.Fl a ,
95but it can be used with
96.Fl f
97and/or
98.Fl v .
99This is the only way to unmount something that does not appear as a
100directory (such as a nullfs mount of a plain file); there are probably
101other cases where it is necessary.
102.It Fl h Ar host
103Only filesystems mounted from the specified host will be
104unmounted.
105This option is implies the
106.Fl A
107option and, unless otherwise specified with the
108.Fl t
109option, will only unmount NFS filesystems.
110.It Fl t Ar type
111Is used to indicate the actions should only be taken on
112filesystems of the specified type.
113More than one type may be specified in a comma separated list.
114The list of filesystem types can be prefixed with
115.Dq no
116to specify the filesystem types for which action should
117.Em not
118be taken.
119For example, the
120.Nm
121command:
122.Bd -literal -offset indent
123umount -a -t nfs,mfs
124.Ed
125.Pp
126umounts all filesystems of the type
127.Tn NFS
128and
129.Tn MFS .
130.It Fl v
131Verbose, additional information is printed out as each filesystem
132is unmounted.
133.El
134.Sh FILES
135.Bl -tag -width /etc/fstab -compact
136.It Pa /etc/fstab
137filesystem table
138.El
139.Sh SEE ALSO
140.Xr unmount 2 ,
141.Xr fstab 5 ,
142.Xr mount 8
143.Sh HISTORY
144A
145.Nm
146command appeared in
147.At v6 .
148