allow terminal window to be opened from command line * command-widget.h, command-widget.cc (command_widget::update_prompt): New slot. (command_widget::insert_interpreter_output): Now public. (command_widget::command_widget): Don't connect to signals from parent object here. * octave-qobject.h, octave-qobject.cc (base_qobject::m_terminal_widget): New data member. (base_qobject::terminal_widget): New function. Make (command_widget, QTerminal)/base_qobject signal/slot connections here instead of in main_window constructor. (base_qobject::show_terminal_window): New slot. (base_qobject::base_qobject): Connect qt_interpreter_events::show_terminal_window_signal to base_qobject::show_terminal_window slot. (base_qobject::~base_qobject): Close and delete terminal widget. * main-window.h, main-window.cc (main_window::main_window): Acquire m_command_window from base_qobject instead of constructing here. * terminal-dock-widget.cc (terminal_dock_widget::terminal_dock_widget): Make dock widget/terminal widget signal/slot connections here instead of in main window constructor. Call make_window if parent object is nullptr. * event-manager.h, event-manager.cc (F__event_manager_show_terminal_window__): New function. (interpreter_events::show_terminal_window): New virtual function. (event_manager::show_terminal_window): New function. * qt-interpreter-events.h, qt-interpreter-events.cc (qt_interpreter_events::show_terminal_window): New signal (qt_interpreter_events::show_terminal_window): New function.

--- a/libgui/src/octave-qobject.h	Sat Jun 19 10:33:37 2021 -0400
+++ b/libgui/src/octave-qobject.h	Sat Jun 19 14:34:07 2021 -0400
@@ -83,6 +83,7 @@
   class file_editor_interface;
   class files_dock_widget;
   class history_dock_widget;
+  class terminal_dock_widget;
   class variable_editor;
   class workspace_model;
   class workspace_view;
@@ -153,6 +154,9 @@
       return m_workspace_model;
     }
 
+    QPointer<terminal_dock_widget>
+    terminal_widget (main_window *mw = nullptr);
+
     QPointer<documentation_dock_widget>
     documentation_widget (main_window *mw = nullptr);
 
@@ -199,6 +203,8 @@
     void start_gui (bool gui_app);
     void close_gui (void);
 
+    void show_terminal_window (void);
+
     void show_documentation_window (const QString& file);
 
     void show_file_browser_window (void);
@@ -268,6 +274,8 @@
     // adopted by the desktop (main window) if it is also started from
     // the command line.
 
+    QPointer<terminal_dock_widget> m_terminal_widget;
+
     QPointer<documentation_dock_widget> m_documentation_widget;
 
     QPointer<files_dock_widget> m_file_browser_widget;