If .biewrc does not exist, the setup dialog appears at program start. If you try
to click a checkbox with the mouse, biew tries to dereference a null pointer
(because the MainWindow is not yet set).

This patch adds a workaround. Note that you actually cannot click a checkbox.
But that is what users might expect. (Maybe the biew code should be changed to
handle this properly.) Well, it is better not to crash, even if the checkboxes
are not clickable.

 –nico


diff -Naur biew-610.orig/events.c biew-610/events.c
--- biew-610.orig/events.c	2009-09-03 16:57:40.000000000 +0000
+++ biew-610/events.c	2011-09-06 09:41:01.000000000 +0000
@@ -118,7 +118,11 @@
                     }
                     else
                     {
-                      X1 = 0; X2 = twGetClientWidth(MainWnd); Y1 = 1; Y2 = twGetClientHeight(MainWnd) - 1;
+                      TWindow *wnd =
+                              MainWnd ? MainWnd :  /*XXX:drop this line?*/
+                              twGetWinAtPos(mx, my);
+                      if(!wnd) return KE_MOUSE;
+                      X1 = 0; X2 = twGetClientWidth(wnd); Y1 = 1; Y2 = twGetClientHeight(wnd) - 1;
                     }
                     wdh = X2 - X1;
                     hght = Y2 - Y1;