added localinterfaces to utils

IPython/utils/localinterfaces.py

@@ -0,0 +1,40 b''
+"""Simple utility for building a list of local IPs using the socket module.
+This module defines two constants:
+
+LOCALHOST : The loopback interface, or the first interface that points to this 
+            machine.  It will *almost* always be '127.0.0.1'
+
+LOCAL_IPS : A list of IP addresses, loopback first, that point to this machine.
+"""
+#-----------------------------------------------------------------------------
+#  Copyright (C) 2010  The IPython Development Team
+#
+#  Distributed under the terms of the BSD License.  The full license is in
+#  the file COPYING, distributed as part of this software.
+#-----------------------------------------------------------------------------
+
+#-----------------------------------------------------------------------------
+# Imports
+#-----------------------------------------------------------------------------
+
+import socket
+
+#-----------------------------------------------------------------------------
+# Code
+#-----------------------------------------------------------------------------
+
+LOCAL_IPS = []
+try:
+    LOCAL_IPS = socket.gethostbyname_ex('localhost')[2]
+except socket.gaierror:
+    pass
+
+try:
+    LOCAL_IPS.extend(socket.gethostbyname_ex(socket.gethostname())[2])
+except socket.gaierror:
+    pass
+
+# include all-interface aliases: 0.0.0.0 and ''
+LOCAL_IPS.extend(['0.0.0.0', ''])
+
+LOCALHOST = LOCAL_IPS[0]