open editor tab and insert marker for debugging with gui * file-editor-interface.h (file_editor_interface::request_open_file): New public slot. (file_editor_interface::handle_dbstop_request): New virtual function. * file-editor-tab.h, file-editor-tab.cc (file_editor_tab::goto_line): New arg, line, with default value. Don't prompt if line is greater than zero. (file_editor_tab::set_debugger_position): New arg, widget id. (file_editor_tab::add_filename_to_list): New arg, widget id. * file-editor.h, file-editor.cc (file_eidtor::editor_tab_map): New data member. (file_editor::fetFileNames) Delete. (file_editor::~file_editor, file_editor::check_conflict_save, file_editor::handle_add_filename_to_list): Use editor_tab_map instead of fetFileNames. (file_editor::request_open_file): New args, line and set_marker. Optionally position cursor at line and with debug marker. If file is already open in tab, switch to it instead of giving error. (file_editor::construct): Connect fetab_set_debugger_position signal to set_debugger_position slot. * main-window.h, main-window.cc (main_window::dbstop_signal): New signal. (main_window::handle_dbstop_request): New function. * octave-event-listener.h (octave_event_listener::dbstop): New virtual function. * octave-qt-event-listener.h, octave-qt-event-listener.cc (octave_qt_event_listener::dbstop): New function. (octave_qt_event_listener::dbstop_signal): New signal. * octave-link.h, octave-link.cc (octave_link::dbstop, octave_link::do_dbstop, octave_link::dbstop_event_hook_fcn, octave_link::do_dbstop_event_hook_fcn): New functions * octave-main-thread.h, octave-main-thread.cc (dbstop_event_hook_fcn): New function. (octave_main_thread::run): Add it to the list of dbstop event hook functions.

--- a/libgui/src/m-editor/file-editor-tab.cc	Wed Mar 27 00:45:49 2013 -0400
+++ b/libgui/src/m-editor/file-editor-tab.cc	Wed Mar 27 12:59:12 2013 -0400
@@ -629,19 +629,26 @@
 }
 
 void
-file_editor_tab::goto_line (const QWidget* ID)
+file_editor_tab::goto_line (const QWidget* ID, int line)
 {
   if (ID != this)
     return;
 
-  int line, index;
+  bool ok = true;
 
-  _edit_area->getCursorPosition(&line, &index);
+  if (line <= 0)
+    {
+      bool ok = false;
+
+      int index;
 
-  bool ok = false;
+      _edit_area->getCursorPosition(&line, &index);
+
 
-  line = QInputDialog::getInt (_edit_area, "Goto line", "Line number", 
-                               line+1, 1, _edit_area->lines(), 1, &ok);
+      line = QInputDialog::getInt (_edit_area, "Goto line", "Line number", 
+                                   line+1, 1, _edit_area->lines(), 1, &ok);
+    }
+
   if (ok)
     _edit_area->setCursorPosition (line-1, 0);
 }
@@ -1103,7 +1110,7 @@
 
   // Unnamed files shouldn't be transmitted.
   if (!_file_name.isEmpty ())
-    emit add_filename_to_list (_file_name);
+    emit add_filename_to_list (_file_name, this);
 }
 
 void
@@ -1140,8 +1147,11 @@
 }
 
 void
-file_editor_tab::set_debugger_position (int line)
+file_editor_tab::set_debugger_position (const QWidget *ID, int line)
 {
+  if (ID != this || ID == 0)
+    return;
+
   _edit_area->markerDeleteAll (debugger_position);
   if (line > 0)
     {