diff --git a/test/subset/run-tests.py b/test/subset/run-tests.py
index 072a49d5f968b943179fe2d7003c2e366df81e32..4c77de097880a316cab4c7f4e23072b6f67b300c 100755
--- a/test/subset/run-tests.py
+++ b/test/subset/run-tests.py
@@ -19,9 +19,9 @@ from subset_test_suite import SubsetTestSuite
 def cmd(command):
 	p = subprocess.Popen (
 		command, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
-	p.wait ()
-	print (p.stderr.read (), end="") # file=sys.stderr
-	return p.stdout.read (), p.returncode
+	(stdoutdata, stderrdata) = p.communicate()
+	print (stderrdata, end="") # file=sys.stderr
+	return stdoutdata, p.returncode
 
 def read_binary(file_path):
 	with open(file_path, 'rb') as f: