From 7c0d1506e7b75c213080e99ff1a520b914018c1d Mon Sep 17 00:00:00 2001
From: Damien Saucez <damien.saucez@gmail.com>
Date: Tue, 23 Apr 2019 08:42:07 +0200
Subject: [PATCH] change isShellBuiltin

change isShellBuiltin to have each builtin as a different token in a set and lookup cmd to be an element of the set instead of a sequence of characters in a string (tested only on Python 3.6.7). Corrected according to @lantz comments.
---
 mininet/util.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mininet/util.py b/mininet/util.py
index 3a97c4c..f551737 100644
--- a/mininet/util.py
+++ b/mininet/util.py
@@ -181,7 +181,7 @@ def which(cmd, **kwargs ):
 def isShellBuiltin( cmd ):
     "Return True if cmd is a bash builtin."
     if isShellBuiltin.builtIns is None:
-        isShellBuiltin.builtIns = quietRun( 'bash -c enable' )
+        isShellBuiltin.builtIns = set(quietRun( 'bash -c enable' ).split())
     space = cmd.find( ' ' )
     if space > 0:
         cmd = cmd[ :space]