1.\" $NetBSD: umount.8,v 1.15 2009/05/17 14:09:15 mjf 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 17, 2009 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.Op Fl t Ar fstypelist 42.Ar special | node 43.Nm 44.Fl a 45.Op Fl fvF 46.Op Fl h Ar host 47.Op Fl t Ar fstypelist 48.Sh DESCRIPTION 49The 50.Nm 51command 52calls the 53.Xr unmount 2 54system call to remove a 55.Ar "special device" 56or the remote node (rhost:path) from the filesystem tree at the point 57.Ar node . 58If either 59.Ar special 60or 61.Ar node 62are not provided, the appropriate information is taken from the 63.Xr fstab 5 64file. 65.Pp 66The options are as follows: 67.Bl -tag -width indent 68.It Fl a 69All the currently mounted filesystems except the root are unmounted. 70.It Fl f 71The filesystem is forcibly unmounted. 72Active special devices continue to work, 73but all other files return errors if further accesses are attempted. 74The root filesystem cannot be forcibly unmounted. 75.It Fl F 76Fake the unmount; perform all other processing but do not actually 77attempt the unmount. 78(This is most useful in conjunction with 79.Fl v , 80to see what 81.Nm 82would attempt to do). 83.It Fl R 84Take the 85.Ar special | node 86argument as a path to be passed directly to 87.Xr unmount 2 , 88bypassing all attempts to be smart about mechanically determining the 89correct path from the argument. 90This option is incompatible with any option that potentially unmounts 91more than one filesystem, such as 92.Fl a , 93but it can be used with 94.Fl f 95and/or 96.Fl v . 97This is the only way to unmount something that does not appear as a 98directory (such as a nullfs mount of a plain file); there are probably 99other cases where it is necessary. 100.It Fl h Ar host 101Only filesystems mounted from the specified host will be 102unmounted. 103This option is implies the 104.Fl a 105option and, unless otherwise specified with the 106.Fl t 107option, will only unmount NFS filesystems. 108.It Fl t Ar fstypelist 109Is used to indicate the actions should only be taken on 110filesystems of the specified type. 111More than one type may be specified in a comma separated list. 112The list of filesystem types can be prefixed with 113.Dq no 114to specify the filesystem types for which action should 115.Em not 116be taken. 117For example, the 118.Nm 119command: 120.Bd -literal -offset indent 121umount -a -t nfs,mfs 122.Ed 123.Pp 124unmounts all filesystems of the type 125.Tn NFS 126and 127.Tn MFS , 128whereas the 129.Nm 130command: 131.Bd -literal -offset indent 132umount -a -t nonfs,mfs 133.Ed 134.Pp 135unmounts all file systems except those of type 136.Tn NFS 137and 138.Tn MFS . 139.It Fl v 140Verbose, additional information is printed out as each filesystem 141is unmounted. 142.El 143.Sh FILES 144.Bl -tag -width /etc/fstab -compact 145.It Pa /etc/fstab 146filesystem table 147.El 148.Sh SEE ALSO 149.Xr unmount 2 , 150.Xr fstab 5 , 151.Xr mount 8 152.Sh HISTORY 153A 154.Nm 155command appeared in 156.At v6 . 157