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$FreeBSD$
.Dd April 27, 2020 .Dt UNIONFS 5 .Os .Sh NAME .Nm unionfs .Nd "UNION FS" .Sh SYNOPSIS To compile this driver into the kernel, place the following lines in your kernel configuration file: d -ragged -offset indent .Cd "option UNIONFS" .Ed
p Alternatively, to load the driver as a module at boot time, place the following line in .Xr loader.conf 5 : d -literal -offset indent unionfs_load="YES" .Ed .Sh DESCRIPTION The UNIONFS driver is an implementation of a stackable unification filesystem. .Sh SEE ALSO .Xr mount_unionfs 8 .Sh STANDARDS .Rs .%T Union mounts in 4.4BSD-Lite .%A J. S. Pendry .%A M. K. McKusick .%R Proceedings of the USENIX Technical Conference on UNIX and Advanced Computing Systems .%D December 1995 .Re
p .Rs .%T Jails: Confining the omnipotent root .%A P. H. Kamp .%A R. N. M. Watson .%R Proceedings of the Second International System Administration and Networking Conference (SANE2000) .%D May 2000 .Re .Sh HISTORY The .Nm device driver first appeared in .Fx 5.0 . .Sh AUTHORS The .Nm device driver was written by Jan-Simon Pendry for x 4.4 and .An Masanori OZAWA Aq Mt ozawa@ongs.co.jp reimplemented the handling of the locking for .Fx 7.0 . The manual page was written by .An Gordon Bergling Aq Mt gbe@FreeBSD.org . .Sh BUGS Please see the .Xr mount_unionfs 8 manual page for a list of bugs regarding the .Nm filesystem.