shithub: unionfs

ref: e487ce5cb024451edb81acacc3524259019a8569
dir: /unionfs.man/

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.TH UNIONFS 4
.SH NAME
unionfs \- union file server
.SH SYNOPSIS
.B unionfs
[
.B -D
]
[
.B -abC
]
.B -m
.I mtpt
|
.B -s
.I srvname
[
[
.B -c
]
.I path ....
]
.SH DESCRIPTION
.PP
.I Unionfs
serves a file tree that represents a deep
merge of the file trees given by one or
more of the
.I path
arguments.
.PP
Unlike the namespace operators described in
.IR bind (2),
which merge directory contents
only on a single - mountpoint - level,
.I unionfs
does a deep merge. This means that
if more than one file tree contains a
directory of the same name at any
point in the union tree, traversing that
point will return the combined content
of the overlapping directories - instead
of only the first one in the union list.
.PP
An ordered list of
.I path
arguments must be given. This list
influences the tree walking and other file
operations in a similar fashion as the
system-provided union lists.
If the
.I -c
flag is prefixed to the path, that tree
will be marked as the target for file
creation; otherwise the first path in the
list will be used. 
.PP
Either of the
.I -m
or
.I -s
options is required; the former specifies
a mount point at which to mount the
file server and the latter causes the
server file descriptor to be posted to the
.IR srv (3)
device.
.PP
The options
.I -a, -b
and
.I -C
control the mounting of the file server at
.I mtpt
as described in
.IR bind (1).
.PP
The
.I -D
option causes
.IR 9p (2)
trace to be output to the standard error
during runtime.
.SS Examples
.EX
unionfs -m /bin /rc/bin /arm/bin -c $home/bin/^(rc arm)
.EE
.SH SEE ALSO
.IR bind (1),
.IR bind (2)
.SH SOURCE
.B https://bitbucket.org/k-vik/unionfs
.SH BUGS
.PP
You're.