.\" $OpenBSD: lndir.1,v 1.23 2008/01/11 20:16:02 jmc Exp $
.\"
.\" Copyright (c) 1997, Jason Downs.  All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS
.\" OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
.\" WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
.\" DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT,
.\" INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
.\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
.\" SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
.\" CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\" $XConsortium: lndir.man /main/9 1995/12/15 14:00:35 gildea $
.\"
.\" Copyright (c) 1993, 1994  X Consortium
.\"
.\" Permission is hereby granted, free of charge, to any person obtaining
.\" a copy of this software and associated documentation files (the
.\" "Software"), to deal in the Software without restriction, including
.\" without limitation the rights to use, copy, modify, merge, publish,
.\" distribute, sublicense, and/or sell copies of the Software, and to
.\" permit persons to whom the Software is furnished to do so, subject to
.\" the following conditions:
.\"
.\" The above copyright notice and this permission notice shall be
.\" included in all copies or substantial portions of the Software.
.\"
.\" THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
.\" EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
.\" IN NO EVENT SHALL THE X CONSORTIUM BE LIABLE FOR ANY CLAIM, DAMAGES OR
.\" OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
.\" ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
.\" OTHER DEALINGS IN THE SOFTWARE.
.\"
.\" Except as contained in this notice, the name of the X Consortium shall
.\" not be used in advertising or otherwise to promote the sale, use or
.\" other dealings in this Software without prior written authorization
.\" from the X Consortium.
.\"
.Dd $Mdocdate: January 11 2008 $
.Dt LNDIR 1
.Os
.Sh NAME
.Nm lndir
.Nd "create a shadow directory of symbolic links to another directory tree"
.Sh SYNOPSIS
.Nm lndir
.Op Fl is
.Op Fl e Ar exceptfile
.Ar fromdir
.Op Ar todir
.Sh DESCRIPTION
The
.Nm
program makes a shadow copy
.Ar todir
of a directory tree
.Ar fromdir ,
except that the shadow is not
populated with real files but instead with symbolic links pointing at
the real files in the
.Ar fromdir
directory tree.
This is usually useful for maintaining source code for
different machine architectures.
You create a shadow directory
containing links to the real source, which you will have usually
mounted from a remote machine.
You can build in the shadow tree, and
the object files will be in the shadow directory, while the
source files in the shadow directory are just symlinks to the real
files.
.Pp
This scheme has the advantage that if you update the source, you need not
propagate the change to the other architectures by hand, since all
source in all shadow directories are symlinks to the real thing:
just change working directory to the shadow directory and recompile away.
.Pp
The
.Ar todir
argument is optional and defaults to the current directory.
The
.Ar fromdir
argument may be relative (e.g.\&
.Pa ../src )
and is relative to
.Ar todir
(not the current directory).
.Pp
If you add files, simply run
.Nm
again.
New files will be silently added.
Old files will be
checked that they have the correct link.
.Pp
Deleting files is a more painful problem; the symlinks will
just point into never never land.
.Pp
The options are as follows:
.Bl -tag -width Ds
.It Fl e Ar exceptfile
Add the specified file to the list of excluded files/directories.
This is effective in all directories searched by
.Nm .
This option may be specified as many times as needed.
.Pp
The following types of files are excluded by default:
.Pp
.Bl -dash -offset indent -compact
.It
files whose names end in
.Sq ~
.It
files whose names start with
.Sq .#
.It
RCS, SCCS, CVS, and CVS.adm directories
.El
.It Fl i
If a file in
.Ar fromdir
is a symbolic link,
.Nm
will make the same link in
.Ar todir
rather than making a link back to the (symbolic link) entry in
.Ar fromdir .
The
.Fl i
flag changes that behavior,
i.e. it causes the program to not treat symbolic links in
.Ar fromdir
specially.
The link created in
.Ar todir
will point back to the corresponding (symbolic link) file in
.Ar fromdir .
If the link is to a directory, this is almost certainly the wrong thing.
.Pp
This option exists mostly to emulate the behavior the C version of
.Nm
had in X11R6.
Its use is not recommended.
.It Fl s
Suppresses status messages normally output as
.Nm
descends into each subdirectory.
.El
.Sh DIAGNOSTICS
The program displays the name of each subdirectory it enters, followed
by a colon.
The
.Fl s
option suppresses these messages.
.Pp
A warning message is displayed if the symbolic link cannot be created.
The usual problem is that a regular file of the same name already
exists.
.Pp
If the link already exists but doesn't point to the correct file, the
program prints the link name and the location where it does point.
.Sh SEE ALSO
.Xr find 1 ,
.Xr ln 1 ,
.Xr patch 1
.Sh HISTORY
.Nm
was first distributed as part of X11.
.Pp
This version first appeared in
.Ox 1.2 .
.Sh BUGS
The
.Xr patch 1
program gets upset if it cannot change the files.
You should never run
.Xr patch 1
from a shadow directory anyway.
.Pp
To clear out all files before you can relink
(if
.Ar fromdir
moved, for instance):
.Bd -literal -offset indent
$ find todir -type l -print0 | xargs -0 -r rm
.Ed
.Pp
Find all files that are not directories:
.Bd -literal -offset indent
$ find . ! -type d -print0
.Ed