From a5af91d0d39b09aaf8cdea194da9b2f5f17b3637 Mon Sep 17 00:00:00 2001
From: Bob Lantz <rlantz@cs.stanford.edu>
Date: Thu, 22 Mar 2012 19:08:09 -0700
Subject: [PATCH] Have errFail report cmd and stderr as well as exit code.

---
 mininet/util.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/mininet/util.py b/mininet/util.py
index 11a30a1..bd61fae 100644
--- a/mininet/util.py
+++ b/mininet/util.py
@@ -102,8 +102,8 @@ def errFail( *cmd, **kwargs ):
     "Run a command using errRun and raise exception on nonzero exit"
     out, err, ret = errRun( *cmd, **kwargs )
     if ret:
-        raise Exception( "errFail: failed with return code %s"
-                         % ret )
+        raise Exception( "errFail: %s failed with return code %s: %s"
+                         % ( cmd, ret, err ) )
     return out, err, ret
 
 def quietRun( cmd, **kwargs ):