--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/scripts/testfun/__debug_octave__.m	Wed Jul 29 11:43:16 2020 -0400
@@ -0,0 +1,71 @@
+########################################################################
+##
+## Copyright (C) 2020 The Octave Project Developers
+##
+## See the file COPYRIGHT.md in the top-level directory of this
+## distribution or <https://octave.org/copyright/>.
+##
+## 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
+## <https://www.gnu.org/licenses/>.
+##
+########################################################################
+
+## -*- texinfo -*-
+## @deftypefn  {} {} __debug_octave__ ()
+## @deftypefnx {} {} __debug_octave__ (@var{command_string})
+## Try to open a terminal window with gdb connected to the current
+## Octave process.
+##
+## If @var{command_string} is not supplied, it should have a single
+## @qcode{%d} format option that will be replaced by the process ID
+## for the current Octave process, as returned by @code{getpid}.  For
+## example, on Windows systems the following two commands are
+## equivalent:
+##
+## @example
+## __debug_octave__ ()
+## __debug_octave__ ("start gdb -p %d")
+## @end example
+## @end deftypefn
+
+function __debug_octave__ (command_string)
+
+  if (nargin > 1)
+    print_usage ();
+  endif
+
+  if (nargin == 0)
+    [status, ~] = system ("gdb --version");
+    if (status != 0)
+      error ("unable to execute gdb");
+    endif
+    if (isunix ())
+      ## FIXME: is there a portable way to run a command in a new window?
+      ## Obviously, gnome-terminal is not always available.
+      command_string = "gnome-terminal -- gdb -p %d";
+    elseif (ispc ())
+      command_string = "start gdb -p %d";
+    elseif (ismac ())
+      command_string = "osascript -e 'tell application \"Terminal\" to do script \"lldb -p %d\"'";
+    else
+      error ("unknown system -- unable to determine how to start debugger");
+    endif
+  endif
+
+  system (sprintf (command_string, getpid ()));
+
+endfunction
+

--- a/scripts/testfun/module.mk	Sat Jul 25 21:09:53 2020 +0200
+++ b/scripts/testfun/module.mk	Wed Jul 29 11:43:16 2020 -0400
@@ -9,6 +9,7 @@
   %reldir%/private/html_plot_demos_template.html
 
 %canon_reldir%_FCN_FILES = \
+  %reldir%/__debug_octave__.m \
   %reldir%/__have_feature__.m \
   %reldir%/__printf_assert__.m \
   %reldir%/__prog_output_assert__.m \