diff --git a/bindings/python/ns3modulescan.py b/bindings/python/ns3modulescan.py
index a116732a8..a89176dcc 100644
--- a/bindings/python/ns3modulescan.py
+++ b/bindings/python/ns3modulescan.py
@@ -253,7 +253,7 @@ class MyPygenClassifier(PygenClassifier):
 
 def ns3_module_scan(top_builddir, pygen_file_name, everything_h, cflags):
 
-    ns3_modules = eval(sys.stdin.read())
+    ns3_modules = eval(sys.stdin.readline())
 
     ## do a topological sort on the modules graph
     from topsort import topsort
diff --git a/bindings/python/wscript b/bindings/python/wscript
index 6aa044384..68f7fe40b 100644
--- a/bindings/python/wscript
+++ b/bindings/python/wscript
@@ -437,7 +437,7 @@ class python_scan_task(Task.TaskBase):
             self.cflags,
             ]
         scan = subprocess.Popen(argv, stdin=subprocess.PIPE)
-        scan.stdin.write(repr(get_modules_and_headers(self.bld)))
+        print >> scan.stdin, repr(get_modules_and_headers(self.bld))
         scan.stdin.close()
         retval = scan.wait()
         return retval