diff --git a/Lib/cgi.py b/Lib/cgi.py
index a7ad5bf..14ebeb9 100755
--- a/Lib/cgi.py
+++ b/Lib/cgi.py
@@ -128,7 +128,7 @@
             If false (the default), errors are silently ignored.
             If true, errors raise a ValueError exception.
     """
-    if not fp:
+    if fp is None:
         fp = sys.stdin
     if not environ.has_key('REQUEST_METHOD'):
         environ['REQUEST_METHOD'] = 'GET'       # For testing stand-alone