--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libinterp/corefcn/defaults.in.cc	Wed Jun 28 22:49:03 2017 -0400
@@ -0,0 +1,883 @@
+/*
+
+Copyright (C) 1996-2017 John W. Eaton
+
+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/>.
+
+*/
+
+#if defined (HAVE_CONFIG_H)
+#  include "config.h"
+#endif
+
+#include <cstdlib>
+
+#include <algorithm>
+#include <iostream>
+#include <string>
+
+#include "dir-ops.h"
+#include "oct-env.h"
+#include "file-stat.h"
+#include "pathsearch.h"
+#include "str-vec.h"
+
+#include "defaults.h"
+#include "defun.h"
+#include "error.h"
+#include "file-ops.h"
+#include "errwarn.h"
+#include "help.h"
+#include "input.h"
+#include "load-path.h"
+#include "ovl.h"
+#include "ov.h"
+#include "parse.h"
+#include "interpreter.h"
+#include "unwind-prot.h"
+#include "variables.h"
+#include "version.h"
+
+#if ! defined (OCTAVE_CANONICAL_HOST_TYPE)
+#  define OCTAVE_CANONICAL_HOST_TYPE %OCTAVE_CANONICAL_HOST_TYPE%
+#endif
+
+#if ! defined (OCTAVE_DEFAULT_PAGER)
+#  define OCTAVE_DEFAULT_PAGER %OCTAVE_DEFAULT_PAGER%
+#endif
+
+#if ! defined (OCTAVE_ARCHLIBDIR)
+#  define OCTAVE_ARCHLIBDIR %OCTAVE_ARCHLIBDIR%
+#endif
+
+#if ! defined (OCTAVE_BINDIR)
+#  define OCTAVE_BINDIR %OCTAVE_BINDIR%
+#endif
+
+#if ! defined (OCTAVE_DATADIR)
+#  define OCTAVE_DATADIR %OCTAVE_DATADIR%
+#endif
+
+#if ! defined (OCTAVE_DATAROOTDIR)
+#  define OCTAVE_DATAROOTDIR %OCTAVE_DATAROOTDIR%
+#endif
+
+#if ! defined (OCTAVE_DOC_CACHE_FILE)
+#  define OCTAVE_DOC_CACHE_FILE %OCTAVE_DOC_CACHE_FILE%
+#endif
+
+#if ! defined (OCTAVE_TEXI_MACROS_FILE)
+#  define OCTAVE_TEXI_MACROS_FILE %OCTAVE_TEXI_MACROS_FILE%
+#endif
+
+#if ! defined (OCTAVE_EXEC_PREFIX)
+#  define OCTAVE_EXEC_PREFIX %OCTAVE_EXEC_PREFIX%
+#endif
+
+#if ! defined (OCTAVE_FCNFILEDIR)
+#  define OCTAVE_FCNFILEDIR %OCTAVE_FCNFILEDIR%
+#endif
+
+#if ! defined (OCTAVE_IMAGEDIR)
+#  define OCTAVE_IMAGEDIR %OCTAVE_IMAGEDIR%
+#endif
+
+#if ! defined (OCTAVE_INCLUDEDIR)
+#  define OCTAVE_INCLUDEDIR %OCTAVE_INCLUDEDIR%
+#endif
+
+#if ! defined (OCTAVE_INFODIR)
+#  define OCTAVE_INFODIR %OCTAVE_INFODIR%
+#endif
+
+#if ! defined (OCTAVE_INFOFILE)
+#  define OCTAVE_INFOFILE %OCTAVE_INFOFILE%
+#endif
+
+#if ! defined (OCTAVE_LIBDIR)
+#  define OCTAVE_LIBDIR %OCTAVE_LIBDIR%
+#endif
+
+#if ! defined (OCTAVE_LIBEXECDIR)
+#  define OCTAVE_LIBEXECDIR %OCTAVE_LIBEXECDIR%
+#endif
+
+#if ! defined (OCTAVE_LIBEXECDIR)
+#  define OCTAVE_LIBEXECDIR %OCTAVE_LIBEXECDIR%
+#endif
+
+#if ! defined (OCTAVE_LOCALAPIFCNFILEDIR)
+#  define OCTAVE_LOCALAPIFCNFILEDIR %OCTAVE_LOCALAPIFCNFILEDIR%
+#endif
+
+#if ! defined (OCTAVE_LOCALAPIOCTFILEDIR)
+#  define OCTAVE_LOCALAPIOCTFILEDIR %OCTAVE_LOCALAPIOCTFILEDIR%
+#endif
+
+#if ! defined (OCTAVE_LOCALARCHLIBDIR)
+#  define OCTAVE_LOCALARCHLIBDIR %OCTAVE_LOCALARCHLIBDIR%
+#endif
+
+#if ! defined (OCTAVE_LOCALFCNFILEDIR)
+#  define OCTAVE_LOCALFCNFILEDIR %OCTAVE_LOCALFCNFILEDIR%
+#endif
+
+#if ! defined (OCTAVE_LOCALOCTFILEDIR)
+#  define OCTAVE_LOCALOCTFILEDIR %OCTAVE_LOCALOCTFILEDIR%
+#endif
+
+#if ! defined (OCTAVE_LOCALSTARTUPFILEDIR)
+#  define OCTAVE_LOCALSTARTUPFILEDIR %OCTAVE_LOCALSTARTUPFILEDIR%
+#endif
+
+#if ! defined (OCTAVE_LOCALAPIARCHLIBDIR)
+#  define OCTAVE_LOCALAPIARCHLIBDIR %OCTAVE_LOCALAPIARCHLIBDIR%
+#endif
+
+#if ! defined (OCTAVE_LOCALVERARCHLIBDIR)
+#  define OCTAVE_LOCALVERARCHLIBDIR %OCTAVE_LOCALVERARCHLIBDIR%
+#endif
+
+#if ! defined (OCTAVE_LOCALVERFCNFILEDIR)
+#  define OCTAVE_LOCALVERFCNFILEDIR %OCTAVE_LOCALVERFCNFILEDIR%
+#endif
+
+#if ! defined (OCTAVE_LOCALVEROCTFILEDIR)
+#  define OCTAVE_LOCALVEROCTFILEDIR %OCTAVE_LOCALVEROCTFILEDIR%
+#endif
+
+#if ! defined (OCTAVE_MAN1DIR)
+#  define OCTAVE_MAN1DIR %OCTAVE_MAN1DIR%
+#endif
+
+#if ! defined (OCTAVE_MAN1EXT)
+#  define OCTAVE_MAN1EXT %OCTAVE_MAN1EXT%
+#endif
+
+#if ! defined (OCTAVE_MANDIR)
+#  define OCTAVE_MANDIR %OCTAVE_MANDIR%
+#endif
+
+#if ! defined (OCTAVE_OCTDATADIR)
+#  define OCTAVE_OCTDATADIR %OCTAVE_OCTDATADIR%
+#endif
+
+#if ! defined (OCTAVE_OCTFILEDIR)
+#  define OCTAVE_OCTFILEDIR %OCTAVE_OCTFILEDIR%
+#endif
+
+#if ! defined (OCTAVE_OCTETCDIR)
+#  define OCTAVE_OCTETCDIR %OCTAVE_OCTETCDIR%
+#endif
+
+#if ! defined (OCTAVE_OCTLOCALEDIR)
+#  define OCTAVE_OCTLOCALEDIR %OCTAVE_OCTLOCALEDIR%
+#endif
+
+#if ! defined (OCTAVE_OCTINCLUDEDIR)
+#  define OCTAVE_OCTINCLUDEDIR %OCTAVE_OCTINCLUDEDIR%
+#endif
+
+#if ! defined (OCTAVE_OCTLIBDIR)
+#  define OCTAVE_OCTLIBDIR %OCTAVE_OCTLIBDIR%
+#endif
+
+#if ! defined (OCTAVE_OCTTESTSDIR)
+#  define OCTAVE_OCTTESTSDIR %OCTAVE_OCTTESTSDIR%
+#endif
+
+#if ! defined (OCTAVE_PREFIX)
+#  define OCTAVE_PREFIX %OCTAVE_PREFIX%
+#endif
+
+#if ! defined (OCTAVE_STARTUPFILEDIR)
+#  define OCTAVE_STARTUPFILEDIR %OCTAVE_STARTUPFILEDIR%
+#endif
+
+#if ! defined (OCTAVE_RELEASE)
+#  define OCTAVE_RELEASE %OCTAVE_RELEASE%
+#endif
+
+std::string Voctave_home;
+std::string Voctave_exec_home;
+
+std::string Vbin_dir;
+std::string Vinfo_dir;
+std::string Vdata_dir;
+std::string Vdataroot_dir;
+std::string Vinclude_dir;
+std::string Vlib_dir;
+std::string Vlibexec_dir;
+std::string Varch_lib_dir;
+std::string Vlocal_arch_lib_dir;
+std::string Vlocal_api_arch_lib_dir;
+std::string Vlocal_ver_arch_lib_dir;
+
+std::string Vlocal_ver_oct_file_dir;
+std::string Vlocal_api_oct_file_dir;
+std::string Vlocal_oct_file_dir;
+
+std::string Vlocal_ver_fcn_file_dir;
+std::string Vlocal_api_fcn_file_dir;
+std::string Vlocal_fcn_file_dir;
+
+std::string Voct_data_dir;
+std::string Voct_lib_dir;
+std::string Voct_include_dir;
+std::string Voct_etc_dir;
+std::string Voct_locale_dir;
+
+std::string Vman1_dir = OCTAVE_MAN1DIR;
+std::string Vman1_ext = OCTAVE_MAN1EXT;
+std::string Vman_dir = OCTAVE_MANDIR;
+
+std::string Vlocal_startup_file_dir;
+std::string Voct_tests_dir;
+std::string Vstartupfile_dir;
+
+std::string Voct_file_dir;
+std::string Vfcn_file_dir;
+
+std::string Vimage_dir;
+
+// The path that will be searched for programs that we execute.
+// (--exec-path path)
+static std::string VEXEC_PATH;
+
+// Name of the editor to be invoked by the edit_history command.
+std::string VEDITOR;
+
+std::string Vdefault_pager = OCTAVE_DEFAULT_PAGER;
+std::string Vcanonical_host_type = OCTAVE_CANONICAL_HOST_TYPE;
+std::string Voctave_release = OCTAVE_RELEASE;
+
+static std::string VIMAGE_PATH;
+
+std::string Vlocal_site_defaults_file;
+std::string Vsite_defaults_file;
+
+std::string Vbuilt_in_docstrings_file;
+
+// Variables that name directories or files are substituted into source
+// files with "${prefix}/" stripped from the beginning of the string.
+
+// All configure variables of this form should be specified as absolute
+// directory names.  The only ones that should not be absolute here are
+// ones that have had "${prefix}/" or "${exec_prefix} stripped.
+
+static std::string
+prepend_home_dir (const std::string& hd, const std::string& s)
+{
+  std::string retval = s;
+
+  char dir_sep_char = octave::sys::file_ops::dir_sep_char ();
+
+  if (! octave::sys::env::absolute_pathname (retval))
+    retval = hd + dir_sep_char + s;
+
+  if (dir_sep_char != '/')
+    std::replace (retval.begin (), retval.end (), '/', dir_sep_char);
+
+  return retval;
+}
+
+static std::string
+prepend_octave_home (const std::string& s)
+{
+  return prepend_home_dir (Voctave_home, s);
+}
+
+static std::string
+prepend_octave_exec_home (const std::string& s)
+{
+  return prepend_home_dir (Voctave_exec_home, s);
+}
+
+static void
+set_octave_home (void)
+{
+  std::string op = OCTAVE_PREFIX;
+  std::string oep = OCTAVE_EXEC_PREFIX;
+
+  std::string oh = octave::sys::env::getenv ("OCTAVE_HOME");
+  std::string oeh = octave::sys::env::getenv ("OCTAVE_EXEC_HOME");
+
+  // If OCTAVE_HOME is set in the enviornment, use that.  Otherwise,
+  // default to ${prefix} from configure.
+
+  Voctave_home = (oh.empty () ? op : oh);
+
+  // If OCTAVE_EXEC_HOME is set in the environment, use that.
+  // Otherwise, if ${prefix} and ${exec_prefix} from configure are set
+  // to the same value, use OCTAVE_HOME from the environment if it is set.
+  // Othewise, default to ${exec_prefix} from configure.
+
+  if (! oeh.empty ())
+    Voctave_exec_home = oeh;
+  else
+    {
+      if (op == oep && ! oh.empty ())
+        Voctave_exec_home = oh;
+      else
+        Voctave_exec_home = oep;
+    }
+}
+
+static void
+set_default_info_dir (void)
+{
+  Vinfo_dir = prepend_octave_home (OCTAVE_INFODIR);
+}
+
+static void
+set_default_man_vars (void)
+{
+  Vman_dir = prepend_octave_home (OCTAVE_MANDIR);
+  Vman1_dir = prepend_octave_home (OCTAVE_MAN1DIR);
+  Vman1_ext = prepend_octave_home (OCTAVE_MAN1EXT);
+}
+
+static void
+set_default_data_dirs (void)
+{
+  Vdata_dir = prepend_octave_home (OCTAVE_DATADIR);
+
+  Vdataroot_dir = prepend_octave_home (OCTAVE_DATAROOTDIR);
+}
+
+static void
+set_default_lib_dir (void)
+{
+  Vlib_dir = prepend_octave_exec_home (OCTAVE_LIBDIR);
+}
+
+static void
+set_default_libexec_dir (void)
+{
+  Vlibexec_dir = prepend_octave_exec_home (OCTAVE_LIBEXECDIR);
+}
+
+static void
+set_default_arch_lib_dir (void)
+{
+  Varch_lib_dir = prepend_octave_exec_home (OCTAVE_ARCHLIBDIR);
+}
+
+static void
+set_default_local_arch_lib_dir (void)
+{
+  Vlocal_arch_lib_dir = prepend_octave_exec_home (OCTAVE_LOCALARCHLIBDIR);
+}
+
+static void
+set_default_local_api_arch_lib_dir (void)
+{
+  Vlocal_api_arch_lib_dir = prepend_octave_exec_home (OCTAVE_LOCALAPIARCHLIBDIR);
+}
+
+static void
+set_default_local_ver_arch_lib_dir (void)
+{
+  Vlocal_ver_arch_lib_dir = prepend_octave_exec_home (OCTAVE_LOCALVERARCHLIBDIR);
+}
+
+static void
+set_default_local_ver_oct_file_dir (void)
+{
+  Vlocal_ver_oct_file_dir = prepend_octave_exec_home (OCTAVE_LOCALVEROCTFILEDIR);
+}
+
+static void
+set_default_local_api_oct_file_dir (void)
+{
+  Vlocal_api_oct_file_dir = prepend_octave_exec_home (OCTAVE_LOCALAPIOCTFILEDIR);
+}
+
+static void
+set_default_local_oct_file_dir (void)
+{
+  Vlocal_oct_file_dir = prepend_octave_exec_home (OCTAVE_LOCALOCTFILEDIR);
+}
+
+static void
+set_default_local_ver_fcn_file_dir (void)
+{
+  Vlocal_ver_fcn_file_dir = prepend_octave_home (OCTAVE_LOCALVERFCNFILEDIR);
+}
+
+static void
+set_default_local_api_fcn_file_dir (void)
+{
+  Vlocal_api_fcn_file_dir = prepend_octave_home (OCTAVE_LOCALAPIFCNFILEDIR);
+}
+
+static void
+set_default_local_fcn_file_dir (void)
+{
+  Vlocal_fcn_file_dir = prepend_octave_home (OCTAVE_LOCALFCNFILEDIR);
+}
+
+static void
+set_default_fcn_file_dir (void)
+{
+  Vfcn_file_dir = prepend_octave_home (OCTAVE_FCNFILEDIR);
+}
+
+static void
+set_default_image_dir (void)
+{
+  Vimage_dir = prepend_octave_home (OCTAVE_IMAGEDIR);
+}
+
+static void
+set_default_oct_data_dir (void)
+{
+  Voct_data_dir = prepend_octave_home (OCTAVE_OCTDATADIR);
+}
+
+static void
+set_default_include_dir (void)
+{
+  Vinclude_dir = prepend_octave_home (OCTAVE_INCLUDEDIR);
+}
+
+static void
+set_default_oct_lib_dir (void)
+{
+  Voct_etc_dir = prepend_octave_exec_home (OCTAVE_OCTLIBDIR);
+}
+
+static void
+set_default_oct_include_dir (void)
+{
+  Voct_include_dir = prepend_octave_home (OCTAVE_OCTINCLUDEDIR);
+}
+
+static void
+set_default_oct_etc_dir (void)
+{
+  Voct_etc_dir = prepend_octave_home (OCTAVE_OCTETCDIR);
+}
+
+static void
+set_default_oct_locale_dir (void)
+{
+  Voct_locale_dir = prepend_octave_home (OCTAVE_OCTLOCALEDIR);
+}
+
+static void
+set_default_oct_file_dir (void)
+{
+  Voct_file_dir = prepend_octave_exec_home (OCTAVE_OCTFILEDIR);
+}
+
+static void
+set_default_bin_dir (void)
+{
+  Vbin_dir = prepend_octave_exec_home (OCTAVE_BINDIR);
+}
+
+void
+set_exec_path (const std::string& path_arg)
+{
+  std::string tpath = path_arg;
+
+  if (tpath.empty ())
+    tpath = octave::sys::env::getenv ("OCTAVE_EXEC_PATH");
+
+  if (tpath.empty ())
+    tpath = Vlocal_ver_arch_lib_dir + octave::directory_path::path_sep_str ()
+            + Vlocal_api_arch_lib_dir + octave::directory_path::path_sep_str ()
+            + Vlocal_arch_lib_dir + octave::directory_path::path_sep_str ()
+            + Varch_lib_dir + octave::directory_path::path_sep_str ()
+            + Vbin_dir;
+
+  VEXEC_PATH = tpath;
+
+  // FIXME: should we really be modifying PATH in the environment?
+  // The way things are now, Octave will ignore directories set in the
+  // PATH with calls like
+  //
+  //   setenv ("PATH", "/my/path");
+  //
+  // To fix this, I think Octave should be searching the combination of
+  // PATH and EXEC_PATH for programs that it executes instead of setting
+  // the PATH in the environment and relying on the shell to do the
+  // searching.
+
+  // This is static so that even if set_exec_path is called more than
+  // once, shell_path is the original PATH from the environment,
+  // before we start modifying it.
+  static std::string shell_path = octave::sys::env::getenv ("PATH");
+
+  if (! shell_path.empty ())
+    tpath = shell_path + octave::directory_path::path_sep_str () + tpath;
+
+  octave::sys::env::putenv ("PATH", tpath);
+}
+
+void
+set_image_path (const std::string& path)
+{
+  VIMAGE_PATH = ".";
+
+  std::string tpath = path;
+
+  if (tpath.empty ())
+    tpath = octave::sys::env::getenv ("OCTAVE_IMAGE_PATH");
+
+  if (! tpath.empty ())
+    VIMAGE_PATH += octave::directory_path::path_sep_str () + tpath;
+
+  tpath = octave::genpath (Vimage_dir, "");
+
+  if (! tpath.empty ())
+    VIMAGE_PATH += octave::directory_path::path_sep_str () + tpath;
+}
+
+static void
+set_default_doc_cache_file (void)
+{
+  if (Vdoc_cache_file.empty ())
+    {
+      std::string def_file = prepend_octave_home (OCTAVE_DOC_CACHE_FILE);
+
+      std::string env_file = octave::sys::env::getenv ("OCTAVE_DOC_CACHE_FILE");
+
+      Vdoc_cache_file = (env_file.empty () ? def_file : env_file);
+    }
+}
+
+static void
+set_default_texi_macros_file (void)
+{
+  if (Vtexi_macros_file.empty ())
+    {
+      std::string def_file = prepend_octave_home (OCTAVE_TEXI_MACROS_FILE);
+
+      std::string env_file = octave::sys::env::getenv ("OCTAVE_TEXI_MACROS_FILE");
+
+      Vtexi_macros_file = (env_file.empty () ? def_file : env_file);
+    }
+}
+
+static void
+set_default_info_file (void)
+{
+  if (Vinfo_file.empty ())
+    {
+      std::string std_info_file = prepend_octave_home (OCTAVE_INFOFILE);
+
+      std::string oct_info_file = octave::sys::env::getenv ("OCTAVE_INFO_FILE");
+
+      Vinfo_file = (oct_info_file.empty () ? std_info_file : oct_info_file);
+    }
+}
+
+static void
+set_default_info_prog (void)
+{
+  if (Vinfo_program.empty ())
+    {
+      std::string oct_info_prog = octave::sys::env::getenv ("OCTAVE_INFO_PROGRAM");
+
+      if (oct_info_prog.empty ())
+        Vinfo_program = "info";
+      else
+        Vinfo_program = std::string (oct_info_prog);
+    }
+}
+
+static void
+set_default_editor (void)
+{
+  VEDITOR = "emacs";
+
+  std::string env_editor = octave::sys::env::getenv ("EDITOR");
+
+  if (! env_editor.empty ())
+    VEDITOR = env_editor;
+}
+
+static void
+set_local_site_defaults_file (void)
+{
+  std::string lsf = octave::sys::env::getenv ("OCTAVE_SITE_INITFILE");
+
+  if (lsf.empty ())
+    {
+      Vlocal_site_defaults_file
+        = prepend_octave_home (OCTAVE_LOCALSTARTUPFILEDIR);
+      Vlocal_site_defaults_file.append ("/octaverc");
+    }
+  else
+    Vlocal_site_defaults_file = lsf;
+}
+
+static void
+set_site_defaults_file (void)
+{
+  std::string sf = octave::sys::env::getenv ("OCTAVE_VERSION_INITFILE");
+
+  if (sf.empty ())
+    {
+      Vsite_defaults_file = prepend_octave_home (OCTAVE_STARTUPFILEDIR);
+      Vsite_defaults_file.append ("/octaverc");
+    }
+  else
+    Vsite_defaults_file = sf;
+}
+
+static void
+set_built_in_docstrings_file (void)
+{
+  if (Vbuilt_in_docstrings_file.empty ())
+    {
+      std::string df = octave::sys::env::getenv ("OCTAVE_BUILT_IN_DOCSTRINGS_FILE");
+
+      if (df.empty ())
+        Vbuilt_in_docstrings_file
+          = Voct_etc_dir + octave::sys::file_ops::dir_sep_str () + "built-in-docstrings";
+      else
+        Vbuilt_in_docstrings_file = df;
+    }
+}
+
+void
+install_defaults (void)
+{
+  // OCTAVE_HOME must be set first!
+
+  set_octave_home ();
+
+  set_default_info_dir ();
+
+  set_default_man_vars ();
+
+  set_default_data_dirs ();
+  set_default_lib_dir ();
+  set_default_libexec_dir ();
+  set_default_arch_lib_dir ();
+
+  set_default_include_dir ();
+
+  set_default_local_ver_arch_lib_dir ();
+  set_default_local_api_arch_lib_dir ();
+  set_default_local_arch_lib_dir ();
+
+  set_default_local_ver_oct_file_dir ();
+  set_default_local_api_oct_file_dir ();
+  set_default_local_oct_file_dir ();
+
+  set_default_local_ver_fcn_file_dir ();
+  set_default_local_api_fcn_file_dir ();
+  set_default_local_fcn_file_dir ();
+
+  set_default_oct_data_dir ();
+  set_default_oct_lib_dir ();
+  set_default_oct_include_dir ();
+  set_default_oct_etc_dir ();
+  set_default_oct_locale_dir ();
+
+  set_default_fcn_file_dir ();
+  set_default_oct_file_dir ();
+
+  set_default_image_dir ();
+
+  set_default_bin_dir ();
+
+  set_exec_path ();
+
+  set_image_path ();
+
+  set_default_doc_cache_file ();
+
+  set_default_texi_macros_file ();
+
+  set_default_info_file ();
+
+  set_default_info_prog ();
+
+  set_default_editor ();
+
+  set_local_site_defaults_file ();
+
+  set_site_defaults_file ();
+
+  set_built_in_docstrings_file ();
+}
+
+DEFUN (EDITOR, args, nargout,
+       doc: /* -*- texinfo -*-
+@deftypefn  {} {@var{val} =} EDITOR ()
+@deftypefnx {} {@var{old_val} =} EDITOR (@var{new_val})
+@deftypefnx {} {} EDITOR (@var{new_val}, "local")
+Query or set the internal variable that specifies the default text editor.
+
+The default value is taken from the environment variable @w{@env{EDITOR}}
+when Octave starts.  If the environment variable is not initialized,
+@w{@env{EDITOR}} will be set to @qcode{"emacs"}.
+
+When called from inside a function with the @qcode{"local"} option, the
+variable is changed locally for the function and any subroutines it calls.
+The original variable value is restored when exiting the function.
+
+@seealso{edit, edit_history}
+@end deftypefn */)
+{
+  return SET_NONEMPTY_INTERNAL_STRING_VARIABLE (EDITOR);
+}
+
+/*
+%!test
+%! orig_val = EDITOR ();
+%! old_val = EDITOR ("X");
+%! assert (orig_val, old_val);
+%! assert (EDITOR (), "X");
+%! EDITOR (orig_val);
+%! assert (EDITOR (), orig_val);
+
+%!error (EDITOR (1, 2))
+*/
+
+DEFUN (EXEC_PATH, args, nargout,
+       doc: /* -*- texinfo -*-
+@deftypefn  {} {@var{val} =} EXEC_PATH ()
+@deftypefnx {} {@var{old_val} =} EXEC_PATH (@var{new_val})
+@deftypefnx {} {} EXEC_PATH (@var{new_val}, "local")
+Query or set the internal variable that specifies a colon separated
+list of directories to append to the shell PATH when executing external
+programs.
+
+The initial value of is taken from the environment variable
+@w{@env{OCTAVE_EXEC_PATH}}, but that value can be overridden by the command
+line argument @option{--exec-path PATH}.
+
+When called from inside a function with the @qcode{"local"} option, the
+variable is changed locally for the function and any subroutines it calls.
+The original variable value is restored when exiting the function.
+
+@seealso{IMAGE_PATH, OCTAVE_HOME, OCTAVE_EXEC_HOME}
+@end deftypefn */)
+{
+  octave_value retval = SET_NONEMPTY_INTERNAL_STRING_VARIABLE (EXEC_PATH);
+
+  if (args.length () > 0)
+    set_exec_path (VEXEC_PATH);
+
+  return retval;
+}
+
+/*
+%!test
+%! orig_val = EXEC_PATH ();
+%! old_val = EXEC_PATH ("X");
+%! assert (orig_val, old_val);
+%! assert (EXEC_PATH (), "X");
+%! EXEC_PATH (orig_val);
+%! assert (EXEC_PATH (), orig_val);
+
+%!error (EXEC_PATH (1, 2))
+*/
+
+DEFUN (IMAGE_PATH, args, nargout,
+       doc: /* -*- texinfo -*-
+@deftypefn  {} {@var{val} =} IMAGE_PATH ()
+@deftypefnx {} {@var{old_val} =} IMAGE_PATH (@var{new_val})
+@deftypefnx {} {} IMAGE_PATH (@var{new_val}, "local")
+Query or set the internal variable that specifies a colon separated
+list of directories in which to search for image files.
+
+When called from inside a function with the @qcode{"local"} option, the
+variable is changed locally for the function and any subroutines it calls.
+The original variable value is restored when exiting the function.
+
+@seealso{EXEC_PATH, OCTAVE_HOME, OCTAVE_EXEC_HOME}
+@end deftypefn */)
+{
+  return SET_NONEMPTY_INTERNAL_STRING_VARIABLE (IMAGE_PATH);
+}
+
+/*
+%!test
+%! orig_val = IMAGE_PATH ();
+%! old_val = IMAGE_PATH ("X");
+%! assert (orig_val, old_val);
+%! assert (IMAGE_PATH (), "X");
+%! IMAGE_PATH (orig_val);
+%! assert (IMAGE_PATH (), orig_val);
+
+%!error (IMAGE_PATH (1, 2))
+*/
+
+DEFUN (OCTAVE_HOME, args, ,
+       doc: /* -*- texinfo -*-
+@deftypefn {} {} OCTAVE_HOME ()
+Return the name of the top-level Octave installation directory.
+OCTAVE_HOME corresponds to the configuration variable @var{prefix}.
+@seealso{EXEC_PATH, IMAGE_PATH, OCTAVE_EXEC_HOME}
+@end deftypefn */)
+{
+  if (args.length () != 0)
+    print_usage ();
+
+  return ovl (Voctave_home);
+}
+
+/*
+%!assert (ischar (OCTAVE_HOME ()))
+%!error OCTAVE_HOME (1)
+*/
+
+DEFUN (OCTAVE_EXEC_HOME, args, ,
+       doc: /* -*- texinfo -*-
+@deftypefn {} {} OCTAVE_HOME ()
+Return the name of the top-level Octave installation directory for
+architecture-dependendent files.  If not specified separately, the value
+is the same as OCTAVE_HOME.  OCTAVE_EXEC_HOME corresponds to the
+configuration variable @var{exec_prefix}.
+@seealso{EXEC_PATH, IMAGE_PATH, OCTAVE_HOME}
+@end deftypefn */)
+{
+  if (args.length () != 0)
+    print_usage ();
+
+  return ovl (Voctave_exec_home);
+}
+
+/*
+%!assert (ischar (OCTAVE_EXEC_HOME ()))
+%!error OCTAVE_EXEC_HOME (1)
+*/
+
+DEFUNX ("OCTAVE_VERSION", FOCTAVE_VERSION, args, ,
+        doc: /* -*- texinfo -*-
+@deftypefn {} {} OCTAVE_VERSION ()
+Return the version number of Octave as a string.
+@seealso{ver, version}
+@end deftypefn */)
+{
+  if (args.length () != 0)
+    print_usage ();
+
+  return ovl (OCTAVE_VERSION);
+}
+
+/*
+%!assert (ischar (OCTAVE_VERSION ()))
+%!error OCTAVE_VERSION (1)
+*/