function dump_demos (directory, output)
  ## Get path
  if (nargin == 0)
    dirs = strsplit (path (), pathsep ());
  elseif (nargin == 2)
    if (is_absolute_filename (directory))
      dirs = {directory};
    else
      fullname = find_dir_in_path (directory);
      if (! isempty (fullname))
        dirs = {fullname};
      else
        error ("print_demos: expecting argument to be a directory name");
      endif
    endif
  else
    print_usage ();
  endif

  ## Create script beginning (close figures, etc.)
  fid = fopen (output, "w");
  fprintf (fid, "visible = get (0, 'defaultfigurevisible');\n");
  fprintf (fid, "set (0, 'defaultfigurevisible', 'off');\n");
  fprintf (fid, "\n");

  ## Run and print the demos in each directory
  for i = 1:numel (dirs)
    d = dirs{i};
    dump_all_demos (d, fid);
  endfor
  
  ## Create script ending
  fprintf (fid,  "set (0, 'defaultfigurevisible', visible);\n");  
  fclose (fid);
endfunction

function dump_all_demos (directory, fid)
  dirinfo = dir (fullfile (directory, "*.m"));
  flist = {dirinfo.name};
  for i = 1:numel (flist)
    fun = flist{i};
    fun (end-1:end) = []; # remove .m
    demos = get_demos (fun);
    for d = 1:numel (demos)
      fprintf (fid, "\ntry\n");
      fprintf (fid, "  %s\n\n", demos {d});
      fprintf (fid, "  fignum = 1;\n");
      fprintf (fid, "  while (~isempty (get (0, 'currentfigure')))\n");
      fprintf (fid, "    fig = gcf ();\n");
      fprintf (fid, "    figure (fig);\n");
      fprintf (fid, "    name = sprintf ('%s_%d_%%d.png', fignum);\n", fun, d);
      fprintf (fid, "    print (name, '-dpng');\n");
      fprintf (fid, "    close (fig);\n");
      fprintf (fid, "    fignum = fignum + 1;\n");
      fprintf (fid, "  end\n");
      fprintf (fid, "catch\n");
      fprintf (fid, "  fprintf ('%s: %%s\\n', lasterr ());\n", fun);
      fprintf (fid, "end\n\n");
    endfor
  endfor
endfunction

function retval = get_demos (fun)
  [code, idx] = test (fun, "grabdemo");
  num_demos = length (idx) - 1;
  retval = cell (1, num_demos);
  
  ## Simple hacks to make things Matlab compatible
  code = strrep (code, "\"", "'");
  code = strrep (code, "#", "%");
  endkeywords = {"endfor", "endif", "endwhile", "end_try_catch"};
  for k = 1:numel (endkeywords)
    in = endkeywords {k};
    out = in; out (4:end) = " ";
    code = strrep (code, in, out);
  endfor
  
  ## Now split the demos into a cell array
  for k = 1:num_demos
    retval {k} = code (idx (k):idx (k+1)-1);
  endfor
endfunction