.\" $TOG: lndir.man /main/11 1998/02/06 11:23:56 kaleb $
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.TH LNDIR 1 "Release 6.4" "X Version 11"
.SH NAME
lndir \- create a shadow directory of symbolic links to another directory tree
.SH SYNOPSIS
.B lndir
[
.B \-silent
] [
.B \-ignorelinks
]
.I \|fromdir\|
[
.I todir
]
.SH DESCRIPTION
The
.I lndir
program makes a shadow copy 
.I todir 
of a directory tree
.I fromdir, 
except that the shadow is not
populated with real files but instead with symbolic links pointing at
the real files in the 
.I 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 cd
to the shadow directory and recompile away.
.PP
The
.I todir
argument is optional and defaults to the current directory.  The
.I fromdir
argument may be relative (e.g., ../src) and is relative to
.I todir
(not the current directory).
.PP 
.\" CVS.adm is used by the Concurrent Versions System.
Note that RCS, SCCS, CVS and CVS.adm directories are not shadowed.
.PP
If you add files, simply run
.I lndir
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
If a file in \fIfromdir\fP is a symbolic link, \fIlndir\fP will make
the same link in \fItodir\fP rather than making a link back to the
(symbolic link) entry in \fIfromdir.\fP  The \fB\-ignorelinks\fP flag
changes this behavior.
.SH OPTIONS
.IP \-silent
Normally \fIlndir\fP outputs the name of each subdirectory as it
descends into it.  The \fB\-silent\fP option suppresses these status
messages.
.IP \-ignorelinks
Causes the program to not treat symbolic links in \fIfromdir\fP
specially.  The link created in \fItodir\fP will point back to the
corresponding (symbolic link) file in \fIfromdir\fP.
If the link is to a directory, this is almost certainly the wrong thing.
.IP
This option exists mostly to emulate the behavior the C version of
\fIlndir\fP had in X11R6.  Its use is not recommended.
.SH DIAGNOSTICS
The program displays the name of each subdirectory it enters, followed
by a colon.  The \fB\-silent\fP 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 BUGS
The
.I patch
program gets upset if it cannot change the files.  You should never run
.I patch
from a shadow directory anyway.
.PP
You need to use something like
.nf
	find todir \|\-type l \|\-print \||\| xargs rm
.fi
to clear out all files before you can relink (if fromdir moved, for instance).
Something like
.nf
	 find . \|\\! \|\-type d \|\-print
.fi
will find all files that are not directories.