improve Ctrl-C interrupt handling in the GUI (bug #53635) * main-window.h, main-window.cc (octave_interpreter::interrupt): Delete. (octave_interpreter::m_thread_manager): Delete member variable and all uses. * thread-manager.h, thread-manager.cc: Delete. * libgui/src/module.mk: Update. * main-window.h, main-window.cc (main_window::interrupt_interpreter): Delete. (main_window::construct): Don't connect command window interrupt signal to main window interrupt_interpreter slot. * octave-gui.cc (gui_application::execute): Call octave_block_interrupt_signal directly. * terminal-dock-widget.cc (terminal_dock_widget::terminal_interrupt): Set octave_signal_caught and octave_interrupt_state instead of emitting interrupt_signal.

--- a/libgui/src/octave-gui.cc	Thu Apr 12 14:34:10 2018 -0400
+++ b/libgui/src/octave-gui.cc	Tue Apr 17 21:40:31 2018 -0400
@@ -42,6 +42,7 @@
 #include "lo-utils.h"
 #include "oct-env.h"
 #include "oct-syscalls.h"
+#include "signal-wrappers.h"
 
 #include "builtin-defun-decls.h"
 #include "defaults.h"
@@ -54,7 +55,6 @@
 #include "octave-gui.h"
 #include "resource-manager.h"
 #include "shortcut-manager.h"
-#include "thread-manager.h"
 #include "welcome-wizard.h"
 
 // Disable all Qt messages by default.
@@ -84,7 +84,7 @@
 
   int gui_application::execute (void)
   {
-    thread_manager::block_interrupt_signal ();
+    octave_block_interrupt_signal ();
 
     set_application_id ();