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diff --git a/sys-utils/umount.8 b/sys-utils/umount.8 new file mode 100644 index 000000000..d073c55dc --- /dev/null +++ b/sys-utils/umount.8 @@ -0,0 +1,175 @@ +.\" Copyright (c) 1996 Andries Brouwer +.\" This page is somewhat derived from a page that was +.\" (c) 1980, 1989, 1991 The Regents of the University of California +.\" and had been heavily modified by Rik Faith and myself. +.\" +.\" This is free documentation; you can redistribute it and/or +.\" modify it under the terms of the GNU General Public License as +.\" published by the Free Software Foundation; either version 2 of +.\" the License, or (at your option) any later version. +.\" +.\" The GNU General Public License's references to "object code" +.\" and "executables" are to be interpreted as the output of any +.\" document formatting or typesetting system, including +.\" intermediate and printed output. +.\" +.\" This manual is distributed in the hope that it will be useful, +.\" but WITHOUT ANY WARRANTY; without even the implied warranty of +.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +.\" GNU General Public License for more details. +.\" +.\" You should have received a copy of the GNU General Public License along +.\" with this program; if not, write to the Free Software Foundation, Inc., +.\" 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. +.\" +.TH UMOUNT 8 "August 2012" "util-linux" "System Administration" +.SH NAME +umount \- unmount file systems +.SH SYNOPSIS +.B umount +.RB [ \-hV ] +.LP +.B umount \-a +.RB [ \-dflnrv ] +.RB [ \-t +.IR vfstype ] +.RB [ \-O +.IR options ] +.br +.B umount +.RB [ \-dflnrv ] +.RI { dir | device }... +.SH DESCRIPTION +The +.B umount +command detaches the file system(s) mentioned from the file hierarchy. A +file system is specified by giving the directory where it has been +mounted. Giving the special device on which the file system lives may +also work, but is obsolete, mainly because it will fail in case this +device was mounted on more than one directory. +.PP +Note that a file system cannot be unmounted when it is 'busy' - for +example, when there are open files on it, or when some process has its +working directory there, or when a swap file on it is in use. The +offending process could even be +.B umount +itself - it opens libc, and libc in its turn may open for example locale +files. A lazy unmount avoids this problem. +.SH OPTIONS +.TP +\fB\-a\fR, \fB\-\-all\fR +All of the file systems described in +.I /etc/mtab +are unmounted. (With +.B umount +version 2.7 and later: the +.I proc +filesystem is not unmounted.) +.TP +\fB\-c\fR, \fB\-\-no\-canonicalize\fR +Do not canonicalize paths. For more details about this option see the +.B mount(8) +man page. +.TP +\fB\-d\fR, \fB\-\-detach\-loop\fR +In case the unmounted device was a loop device, also free this loop +device. +.TP +\fB\-\-fake\fP +Causes everything to be done except for the actual system call; this +'fakes' unmounting the filesystem. It can be used to remove entries from +.I /etc/mtab +that were unmounted earlier with the +.B \-n +option. +.TP +\fB\-f\fR, \fB\-\-force\fR +Force unmount (in case of an unreachable NFS system). (Requires kernel +2.1.116 or later.) +.TP +\fB\-i\fR, \fB\-\-internal\-only\fR +Do not call the /sbin/umount.<filesystem> helper even if it exists. By +default /sbin/umount.<filesystem> helper is called if one exists. +.TP +\fB\-n\fR, \fB\-\-no\-mtab\fR +Unmount without writing in +.IR /etc/mtab . +.TP +\fB\-l\fR, \fB\-\-lazy\fR +Lazy unmount. Detach the filesystem from the filesystem hierarchy now, +and cleanup all references to the filesystem as soon as it is not busy +anymore. (Requires kernel 2.4.11 or later.) +.TP +\fB\-O\fR, \fB\-\-test\-opts\fR \fIoptions,list\fR +Indicate that the actions should only be taken on file systems with the +specified options in +.IR /etc/fstab . +More than one option type may be specified in a comma separated list. +Each option can be prefixed with +.B no +to specify options for which no action should be taken. +.TP +\fB\-r\fR, \fB\-\-read\-only\fR +In case unmounting fails, try to remount read-only. +.TP +\fB\-t\fR, \fB\-\-types\fR \fIvfstype,ext2,ext3\fR +Indicate that the actions should only be taken on file systems of the +specified +.IR type . +More than one type may be specified in a comma separated list. The list +of file system types can be prefixed with +.B no +to specify the file system types on which no action should be taken. +.TP +\fB\-v\fR, \fB\-\-verbose\fR +Verbose mode. +.TP +\fB\-h\fR, \fB\-\-help\fR +Print help message and exit. +.TP +\fB\-V\fR, \fB\-\-version\fR +Print version and exit. +.SH "THE LOOP DEVICE" +The +.B umount +command will free the loop device (if any) associated with the mount, in +case it finds the option 'loop=...' in +.IR /etc/mtab , +or when the \-d option was given. Any pending loop devices can be freed +using 'losetup -d', see +.BR losetup (8). +.SH NOTES +The syntax of external umount helpers is: +.PP +.BI /sbin/umount. <suffix> +.RI { dir | device } +.RB [ \-nlfvr ] +.RB [ \-t +.IR type.subtype ] +.PP +where the <suffix> is filesystem type or a value from "uhelper=" or +"helper=" mtab option. The \-t option is used for filesystems with +subtypes support (for example /sbin/mount.fuse -t fuse.sshfs). +.PP +The uhelper= (unprivileged umount helper) is possible to use when +non-root user wants to umount a mountpoint which is not defined in the +/etc/fstab file (e.g. devices mounted by udisk). +.PP +The helper= mount option redirects all umount requests to the +/sbin/umount.<helper> independently on UID. +.SH FILES +.I /etc/mtab +table of mounted file systems +.SH "SEE ALSO" +.BR umount (2), +.BR mount (8), +.BR losetup (8) +.SH HISTORY +A +.B umount +command appeared in Version 6 AT&T UNIX. +.SH AVAILABILITY +The umount command is part of the util-linux package and is available from +.UR ftp://\:ftp.kernel.org\:/pub\:/linux\:/utils\:/util-linux/ +Linux Kernel Archive +.UE . |