--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/scripts/path/pathdef.m	Wed Jan 16 06:31:23 2008 +0000
@@ -0,0 +1,96 @@
+## Copyright (C) 2008 Ben Abbott
+##
+## This file is part of Octave.
+##
+## Octave is free software; you can redistribute it and/or modify it
+## under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 3 of the License, or (at
+## your option) any later version.
+##
+## Octave is distributed in the hope that it will be useful, but
+## WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+## General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with Octave; see the file COPYING.  If not, see
+## <http://www.gnu.org/licenses/>.
+
+## -*- texinfo -*-
+## @deftypefn {Function File} {@var{val} =} pathdef ()
+## Return the default path for Octave.
+## The path information is extracted from one of three sources.
+## In order of preference, those are;
+##
+## @enumerate
+## @item @file{~/.octaverc}
+## @item @file{<octave-home>/.../<version>/m/startup/octaverc}
+## @item Octave's path prior to changes by any octaverc.
+## @end enumerate
+## @seealso{path, addpath, rmpath, genpath, savepath, pathsep}
+## @end deftypefn
+
+function val = pathdef ()
+
+  ## Save the path present when called. This will be used to restore
+  ## path when done.
+  presentpath = path;
+
+  ## Use Octave's orignal path as the default default.
+  val = __pathorig__;
+
+  ## Locate the site octaverc file (is there a better way?).
+  prestr = [OCTAVE_HOME, filesep];
+  poststr = [filesep, version, filesep, 'm', filesep', 'startup'];
+  ncolon = [0, strfind(presentpath,':'), numel(presentpath)+1];
+  site_octaverc = '';
+  for nc = 1:(numel(ncolon)-1)
+    pathdir = presentpath((ncolon(nc)+1):(ncolon(nc+1)-1));
+    npre = strfind (pathdir, prestr);
+    npost = strfind (pathdir, poststr);
+    if (npre == 1 &&
+        npost > numel (prestr) &&
+        npost == numel (pathdir) - numel (poststr)+1)
+      site_octaverc = [pathdir, filesep, 'octaverc'];
+      break;
+    endif
+  endfor
+  if isempty (site_octaverc) || ~exist (site_octaverc, 'file')
+    regexp_octaverc = [prestr, '*', poststr, filesep, 'octaverc'];
+    warning (['pathdef: could not locate `',regexp_octaverc,'''.'])
+  endif
+
+  ## locate the user ~\.octaverc file.
+  user_octaverc = tilde_expand ("~/.octaverc");
+
+  ## Extract the specified paths from the site and user octaverc's.
+  site_pathscript = __extractpath__ (site_octaverc);
+  if exist (user_octaverc, 'file')
+    user_pathscript = __extractpath__ (user_octaverc);
+  else
+    user_pathscript = '';
+  endif
+
+  ## A path definition in the user octaverc has precedence over the site
+  if numel (user_pathscript)
+    try
+      eval (user_pathscript);
+      val = path;
+    catch
+      warning (['Path defined in ',user_octaverc,' produced an error'])
+    end_try_catch
+  elseif numel (site_pathscript)
+    try
+      eval (site_pathscript);
+      val = path;
+    catch
+      warning (['Path defined in ',site_octaverc,' produced an error'])
+    end_try_catch
+  endif
+
+  ## Restore the path
+  path (presentpath);
+
+endfunction
+
+