Kernel event loop is robust against random SIGINT.

IPython/zmq/ipkernel.py

@@ -167,8 +167,12 b' class Kernel(Configurable):'
         """ Start the kernel main loop.
         """
         while True:
+            try:
             time.sleep(self._poll_interval)
             self.do_one_iteration()
+            except KeyboardInterrupt:
+                # Ctrl-C shouldn't crash the kernel
+                continue
 
     def record_ports(self, xrep_port, pub_port, req_port, hb_port):
         """Record the ports that this kernel is using.