try this, and if you want to see it without the full input line
redraws, also try it with the //'d line at input.c:399 uncommented
again to have the redraw fix (but this breaks when you type more
than the width of the screen.)


Index: source/input.c
===================================================================
RCS file: /home/cvs/ircii/source/input.c,v
retrieving revision 1.55
diff -p -r1.55 input.c
*** source/input.c	30 Dec 2013 16:42:38 -0000	1.55
--- source/input.c	30 Jan 2014 09:40:32 -0000
*************** input_do_calculate_width(unsigned unival
*** 96,102 ****
  static void
  input_do_set_cursor_pos(unsigned pos)
  {
- 	cursor_to_input();
  	current_screen->inputdata.buffer.pos = pos;
  	update_input(UPDATE_JUST_CURSOR);
  }
--- 96,101 ----
*************** input_do_insert_raw(u_char* source)
*** 116,122 ****
  
  	if (pos + inslen > max)
  	{
! 		inslen = max-pos;
  	}
  
  	/* Move the tail out of way */
--- 115,121 ----
  
  	if (pos + inslen > max)
  	{
! 		inslen = max - pos;
  	}
  
  	/* Move the tail out of way */
*************** input_do_insert_raw(u_char* source)
*** 128,141 ****
  	       source,
  	       inslen);
  	/* Ensure the buffer is terminated */
! 	buf[max-1] = '\0';
  
  	pos += inslen;
  	if (pos > max)
  		pos = max;
  	
  	/* Update the screen from the old cursor position */
- 	cursor_to_input();
  	update_input(UPDATE_FROM_CURSOR);
  	/* Then place the cursor correctly */
  	input_do_set_cursor_pos(pos);
--- 127,139 ----
  	       source,
  	       inslen);
  	/* Ensure the buffer is terminated */
! 	buf[max - 1] = '\0';
  
  	pos += inslen;
  	if (pos > max)
  		pos = max;
  	
  	/* Update the screen from the old cursor position */
  	update_input(UPDATE_FROM_CURSOR);
  	/* Then place the cursor correctly */
  	input_do_set_cursor_pos(pos);
*************** input_do_delete_raw(int n, int do_save_c
*** 148,154 ****
  	unsigned pos = current_screen->inputdata.buffer.pos;
  	unsigned max = sizeof(current_screen->inputdata.buffer.buf);
  
- 	cursor_to_input();
  	/* If n>0, deletes from front
  	 * if n<0, deletes from back & moves cursor
  	 */
--- 146,151 ----
*************** update_input(update)
*** 399,405 ****
  	
  	if (update == UPDATE_FROM_CURSOR)
  	{
! 		old_cursor_pos = inputdata->buffer.pos;
  	}
  	if (update == UPDATE_JUST_CURSOR || update == UPDATE_ALL)
  	{
--- 396,402 ----
  	
  	if (update == UPDATE_FROM_CURSOR)
  	{
! 		//old_cursor_pos = inputdata->buffer.pos;
  	}
  	if (update == UPDATE_JUST_CURSOR || update == UPDATE_ALL)
  	{
*************** update_input(update)
*** 407,413 ****
  		unsigned pos = inputdata->buffer.pos;
  		unsigned limit = inputdata->buffer.minpos;
  		unsigned column, ptr;
- 		
  		unsigned window;
  		
  		/* Recalculate pos_column */
--- 404,409 ----
*************** update_input(update)
*** 424,430 ****
  		inputdata->pos_column = column;
  
  		window = column - (column % inputdata->zone);
! 		
  		/* Recalculate left_ptr */
  		for (column = ptr = 0; column < window; )
  		{
--- 420,426 ----
  		inputdata->pos_column = column;
  
  		window = column - (column % inputdata->zone);
! 
  		/* Recalculate left_ptr */
  		for (column = ptr = 0; column < window; )
  		{
*************** update_input(update)
*** 488,493 ****
--- 484,491 ----
  			}
  		}
  		VisBuf[optr] = '\0';
+ 		if (old_cursor_pos > inputdata->cursor_y)
+ 			old_cursor_pos = 0;
  		term_move_cursor(old_cursor_pos, inputdata->cursor_y);
  		written = output_line(VisBuf + old_cursor_pos, 0);
  		if (term_clear_to_eol() && written < current_screen->co)
Index: source/screen.c
===================================================================
RCS file: /home/cvs/ircii/source/screen.c,v
retrieving revision 1.165
diff -p -r1.165 screen.c
*** source/screen.c	12 Jan 2014 07:05:28 -0000	1.165
--- source/screen.c	30 Jan 2014 09:40:33 -0000
*************** scrollback_backwards_lines(int ScrollDis
*** 2689,2695 ****
  	    window->scrolled_lines,
  	    window);
  	cursor_not_in_display();
! 	update_input(UPDATE_JUST_CURSOR);
  	window->update |= UPDATE_STATUS;
  	update_window_status(window, 0);
  }
--- 2689,2695 ----
  	    window->scrolled_lines,
  	    window);
  	cursor_not_in_display();
! 	update_input(UPDATE_JUST_CURSOR);	// XXXMRG why this?
  	window->update |= UPDATE_STATUS;
  	update_window_status(window, 0);
  }
*************** scrollback_forwards_lines(int ScrollDist
*** 2736,2742 ****
  	    window->scrolled_lines - window->display_size + ScrollDist,
  	    window);
  	cursor_not_in_display();
! 	update_input(UPDATE_JUST_CURSOR);
  
  	if (!window->scrolled_lines)
  	{
--- 2736,2742 ----
  	    window->scrolled_lines - window->display_size + ScrollDist,
  	    window);
  	cursor_not_in_display();
! 	update_input(UPDATE_JUST_CURSOR);	// XXXMRG why this?
  
  	if (!window->scrolled_lines)
  	{
*************** scrollback_end(u_int key, u_char *ptr)
*** 2790,2796 ****
  		window->scrolled_lines = window->new_scrolled_lines = 0;
  		redraw_window(window, 1, 1);
  		cursor_not_in_display();
! 		update_input(UPDATE_JUST_CURSOR);
  		if (window->hold_mode)
  			hold_mode(window, ON, 1);
  		else
--- 2790,2796 ----
  		window->scrolled_lines = window->new_scrolled_lines = 0;
  		redraw_window(window, 1, 1);
  		cursor_not_in_display();
! 		update_input(UPDATE_JUST_CURSOR);	// XXXMRG why this?
  		if (window->hold_mode)
  			hold_mode(window, ON, 1);
  		else
*************** scrollback_start(u_int key, u_char *ptr)
*** 2829,2835 ****
  		display_lastlog_lines(num_lines - window->display_size,
  		    window->scrolled_lines, window);
  		cursor_not_in_display();
! 		update_input(UPDATE_JUST_CURSOR);
  		window->new_scrolled_lines = 0;
  		if (window->hold_mode)
  			hold_mode(window, ON, 1);
--- 2829,2835 ----
  		display_lastlog_lines(num_lines - window->display_size,
  		    window->scrolled_lines, window);
  		cursor_not_in_display();
! 		update_input(UPDATE_JUST_CURSOR);	// XXXMRG why this?
  		window->new_scrolled_lines = 0;
  		if (window->hold_mode)
  			hold_mode(window, ON, 1);
Index: source/window.c
===================================================================
RCS file: /home/cvs/ircii/source/window.c,v
retrieving revision 1.159
diff -p -r1.159 window.c
*** source/window.c	30 Dec 2013 16:42:39 -0000	1.159
--- source/window.c	30 Jan 2014 09:40:33 -0000
*************** redraw_all_status(void)
*** 1493,1499 ****
  		new_free(&tmp->status_line[1]);
  		make_status(tmp);
  	}
! 	update_input(UPDATE_JUST_CURSOR);
  	term_flush();
  }
  
--- 1493,1499 ----
  		new_free(&tmp->status_line[1]);
  		make_status(tmp);
  	}
! 	update_input(UPDATE_JUST_CURSOR);	// XXXMRG why this?
  	term_flush();
  }
  
*************** update_all_status(void)
*** 1519,1525 ****
  			if (window->visible)
  				make_status(window);
  	}
! 	update_input(UPDATE_JUST_CURSOR);
  	term_flush();
  }
  
--- 1519,1525 ----
  			if (window->visible)
  				make_status(window);
  	}
! 	update_input(UPDATE_JUST_CURSOR);	// XXXMRG why this?
  	term_flush();
  }