--- a/libgui/qterminal/libqterminal/win32/QWinTerminalImpl.cpp	Mon Nov 03 22:39:49 2014 -0800
+++ b/libgui/qterminal/libqterminal/win32/QWinTerminalImpl.cpp	Thu Oct 09 19:20:56 2014 -0400
@@ -969,9 +969,30 @@
   m_consoleRect.setWidth (winSize.width () / fm.averageCharWidth ());
   m_consoleRect.setHeight (winSize.height () / fm.lineSpacing ());
 
-  m_bufferSize.rwidth () = m_consoleRect.width ();
-  m_bufferSize.rheight () = qMax (m_bufferSize.height (),
-                                  m_consoleRect.height ());
+  // Don't shrink the size of the buffer.  That way wide lines won't be
+  // truncated and will reappear if the window is enlarged again later.
+
+  if (m_consoleRect.width () > m_bufferSize.width ())
+    m_bufferSize.rwidth () = m_consoleRect.width ();
+
+  if (qMax (m_bufferSize.height (), m_consoleRect.height ())
+      > m_bufferSize.height ())
+    m_bufferSize.rheight () = qMax (m_bufferSize.height (),
+                                    m_consoleRect.height ());
+
+  // Store the terminal size in the environment.  When Octave is
+  // initialized, we ask the command editor (usually readline) to prefer
+  // using these values rather than querying the terminal so that the
+  // buffer size can be larger than the size of the window that the
+  // command editor will actually use.
+
+  qputenv ("LINES", QByteArray::number (m_consoleRect.height ()));
+  qputenv ("COLUMNS", QByteArray::number (m_consoleRect.width ())); 
+
+  // Force the command line editor (usually readline) to notice the
+  // change in screen size as soon as possible.
+
+  q->setSize (m_consoleRect.height (), m_consoleRect.width ());
 
   m_consoleRect.moveLeft (0);
   if (m_consoleRect.bottom () >= m_bufferSize.height ())
@@ -1333,6 +1354,9 @@
     connect (this, SIGNAL (set_global_shortcuts_signal (bool)),
            parent, SLOT (set_global_shortcuts (bool)));
 
+    connect (this, SIGNAL (set_screen_size_signal (int, int)),
+             parent, SLOT (set_screen_size (int, int)));
+
     setAcceptDrops (true);
 }
 
@@ -1644,8 +1668,9 @@
 
 void QWinTerminalImpl::setSize (int columns, int lines)
 {
-  Q_UNUSED (columns);
-  Q_UNUSED (lines);
+  d->log ("emit set_screen_size_signal (%d, %d)\n", columns, lines);
+
+  emit set_screen_size_signal (columns, lines);
 }
 
 //////////////////////////////////////////////////////////////////////////////
@@ -1726,4 +1751,3 @@
       sendText (dropText);
     }
 }
-

--- a/libgui/qterminal/libqterminal/win32/QWinTerminalImpl.h	Mon Nov 03 22:39:49 2014 -0800
+++ b/libgui/qterminal/libqterminal/win32/QWinTerminalImpl.h	Thu Oct 09 19:20:56 2014 -0400
@@ -76,6 +76,7 @@
   void terminated (void);
   void titleChanged (const QString&);
   void set_global_shortcuts_signal (bool);
+  void set_screen_size_signal (int, int);
 
 protected:
   void viewPaintEvent (QConsoleView*, QPaintEvent*);

--- a/libgui/src/main-window.cc	Mon Nov 03 22:39:49 2014 -0800
+++ b/libgui/src/main-window.cc	Thu Oct 09 19:20:56 2014 -0400
@@ -2103,6 +2103,12 @@
 }
 
 void
+main_window::set_screen_size_callback (const int_pair& sz)
+{
+  command_editor::set_screen_size (sz.first, sz.second);
+}
+
+void
 main_window::clear_history_callback (void)
 {
   Fhistory (ovl ("-c"));
@@ -2389,6 +2395,13 @@
 }
 
 void
+main_window::set_screen_size (int ht, int wd)
+{
+  octave_link::post_event (this, &main_window::set_screen_size_callback,
+                           int_pair (ht, wd));
+}
+
+void
 main_window::handle_show_doc (const QString& file)
 {
   doc_browser_window->setVisible (true);

--- a/libgui/src/main-window.h	Mon Nov 03 22:39:49 2014 -0800
+++ b/libgui/src/main-window.h	Thu Oct 09 19:20:56 2014 -0400
@@ -69,6 +69,7 @@
 public:
 
   typedef std::pair <std::string, std::string> name_pair;
+  typedef std::pair <int, int> int_pair;
 
   main_window (QWidget *parent = 0);
 
@@ -196,6 +197,8 @@
   void set_global_shortcuts (bool enable);
   void set_global_edit_shortcuts (bool enable);
 
+  void set_screen_size (int ht, int wd);
+
   // handling the clipboard
   void clipboard_has_changed (QClipboard::Mode);
   void clear_clipboard ();
@@ -252,6 +255,8 @@
 
   void resize_command_window_callback (void);
 
+  void set_screen_size_callback (const int_pair&);
+
   void clear_workspace_callback (void);
 
   void clear_history_callback (void);

--- a/libinterp/corefcn/sysdep.cc	Mon Nov 03 22:39:49 2014 -0800
+++ b/libinterp/corefcn/sysdep.cc	Thu Oct 09 19:20:56 2014 -0400
@@ -169,13 +169,21 @@
 {
   w32_set_quiet_shutdown ();
 }
+
+static void
+w32_init (void)
+{
+  w32_set_octave_home ();
+
+  command_editor::prefer_env_winsize (true);
+}
 #endif
 
 #if defined (__MINGW32__)
 static void
 MINGW_init (void)
 {
-  w32_set_octave_home ();
+  w32_init ();
 }
 #endif
 
@@ -183,7 +191,7 @@
 static void
 MSVC_init (void)
 {
-  w32_set_octave_home ();
+  w32_init ();
 }
 #endif
 

--- a/liboctave/util/cmd-edit.cc	Mon Nov 03 22:39:49 2014 -0800
+++ b/liboctave/util/cmd-edit.cc	Thu Oct 09 19:20:56 2014 -0400
@@ -1447,6 +1447,13 @@
 }
 
 bool
+command_editor::prefer_env_winsize (bool arg)
+{
+  return (instance_ok ())
+         ? instance->do_prefer_env_winsize (arg) : false;
+}
+
+bool
 command_editor::interrupt (bool arg)
 {
   bool retval;