4.4BSD/usr/src/sbin/mount_lofs/mount_lofs.8

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.\"	@(#)mount_lofs.8	8.1 (Berkeley) 6/9/93
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.Dd June 9, 1993
.Dt MOUNT_LOFS 8
.Os BSD 4.4
.Sh NAME
.Nm mount_lofs
.Nd mount a virtual copy of an existing filesystem sub-tree
.Sh SYNOPSIS
.Nm mount_lofs
.Op Fl F Ar fsoptions
.Ar target mount-point
.Sh DESCRIPTION
The
.Nm mount_lofs
command makes a sub-tree of an existing filesystem visible
in another part of the global filesystem namespace.
This allows existing files and directories to be accessed
using a different pathname.
.Pp
The primary differences between a virtual copy of the filesystem
and a symbolic link are that
.Xr getcwd 3
functions correctly in the virtual copy, and that other filesystems
may be mounted on the virtual copy without affecting the original.
A different device number for the virtual copy is returned by
.Xr stat 2 ,
but in other respects it is indistinguishable from the original.
.Sh HISTORY
The
.Nm mount_lofs
utility first appeared in 4.4BSD.