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@(#)umount.8 8.1 (Berkeley) 2/20/94
.Dd February 20, 1994 .Dt UMOUNT 8 .Os BSD 4 .Sh NAME .Nm umount .Nd unmount file systems .Sh SYNOPSIS .Nm umount .Op Fl fv .Ar special | node .Nm umount .Fl a .Op Fl fv .Op Fl h Ar host .Op Fl t Ar ufs | lfs | external_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 file system 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.
p The options are as follows: l -tag -width indent t Fl a All of the file systems described in .Xr fstab 5 are unmounted. t Fl f The file system is forcibly unmounted. Active special devices continue to work, but all other files return errors if further accesses are attempted. The root file system cannot be forcibly unmounted. t 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. t Fl t Ar "ufs \\*(Ba lfs \\*(Ba external 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: d -literal -offset indent umount -a -t nfs,mfs .Ed
p umounts all filesystems of the type .Tn NFS and .Tn MFS . t Fl v Verbose, additional information is printed out as each file system is unmounted. .El .Sh FILES l -tag -width /etc/fstab -compact t Pa /etc/fstab file system 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: d -literal -offset indent <above>/tmpdir on /cdrom (local, user mount) .Ed
p then the command: d -literal -offset indent umount '<above>/tmpdir' .Ed
p would unmount .Ar /tmpdir from the mountpoint .Ar /cdrom . .Sh HISTORY A .Nm umount command appeared in .At v6 .