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