Clean things up slightly.

mininet/clean.py

@@ -47,24 +47,26 @@ def cleanup():
     cleanUpScreens()
 
     info( "*** Removing excess kernel datapaths\n" )
-    dps = sh( "ps ax | egrep -o 'dp[0-9]+' | sed 's/dp/nl:/'" ).split( '\n' )
+    dps = sh( "ps ax | egrep -o 'dp[0-9]+' | sed 's/dp/nl:/'" ).splitlines()
     for dp in dps:
-        if dp != '':
+        if dp:
             sh( 'dpctl deldp ' + dp )
 
     info( "***  Removing OVS datapaths" )
-    dps = sh("ovs-vsctl --timeout=1 list-br").split( '\n' )
-    sh( "ovs-vsctl " + " -- ".join( "--if-exists del-br " + dp for dp in dps if dp ) )
+    dps = sh("ovs-vsctl --timeout=1 list-br").strip().splitlines()
+    if dps:
+        sh( "ovs-vsctl " + " -- ".join( "--if-exists del-br " + dp
+                                       for dp in dps if dp ) )
     # And in case the above didn't work...
-    dps = sh("ovs-vsctl --timeout=1 list-br").split( '\n' )
+    dps = sh("ovs-vsctl --timeout=1 list-br").strip().splitlines()
     for dp in dps:
-        if dp:
-            sh( 'ovs-vsctl del-br ' + dp )
+        sh( 'ovs-vsctl del-br ' + dp )
 
     info( "*** Removing all links of the pattern foo-ethX\n" )
-    links = sh( r"ip link show | egrep -o '([-_.[:alnum:]]+-eth[[:digit:]]+)'" ).split( '\n' )
+    links = sh( "ip link show | "
+                "egrep -o '([-_.[:alnum:]]+-eth[[:digit:]]+)'" ).splitlines()
     for link in links:
-        if link != '':
+        if link:
             sh( "ip link del " + link )
 
     info( "*** Cleanup complete.\n" )