From 1b1058ddb5cef930ae4acb270df0bef11edefde7 Mon Sep 17 00:00:00 2001
From: Steven Silvester <steven.silvester@ieee.org>
Date: Sun, 7 Sep 2014 07:20:44 -0500
Subject: [PATCH] Avoid zombie shells - addresses #30

---
 jupyter_kernel/magics/help_magic.py  | 2 +-
 jupyter_kernel/magics/shell_magic.py | 7 ++++++-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/jupyter_kernel/magics/help_magic.py b/jupyter_kernel/magics/help_magic.py
index 97b28cdc..65a51007 100644
--- a/jupyter_kernel/magics/help_magic.py
+++ b/jupyter_kernel/magics/help_magic.py
@@ -53,7 +53,7 @@ def get_help_on(self, info, level):
         if info['magic']:
 
             if info['magic']['name'] == 'help':
-                return self.get_help('line', 'help')
+                return self.get_help('line', 'help', level)
 
             minfo = info['magic']
             errmsg = "No such %s magic '%s'" % (minfo['type'], minfo['name'])
diff --git a/jupyter_kernel/magics/shell_magic.py b/jupyter_kernel/magics/shell_magic.py
index ec668086..30c08bea 100644
--- a/jupyter_kernel/magics/shell_magic.py
+++ b/jupyter_kernel/magics/shell_magic.py
@@ -5,7 +5,7 @@
 from jupyter_kernel import Magic
 import subprocess
 import os
-import signal
+import atexit
 import threading
 import time
 try:
@@ -86,6 +86,8 @@ def start_process(self):
 
         self.proc = subprocess.Popen(self.cmd, **kwargs)
 
+        atexit.register(self.proc.terminate)
+
         self._error_thread = threading.Thread(target=self._read_errors)
         self._error_queue = Queue.Queue()
         self._error_thread.setDaemon(True)
@@ -116,6 +118,9 @@ def get_help_on(self, info, level=0):
         else:
             return "Sorry, no help is available on '%s'." % expr
 
+    def __del__(self):
+        self.proc.terminate()
+
 
 def register_magics(kernel):
     kernel.register_magics(ShellMagic)