Fixing the NameError on Windows - issue1235

Lib/CGIHTTPServer.py

@@ -271,7 +271,7 @@ class CGIHTTPRequestHandler(SimpleHTTPServer.SimpleHTTPRequestHandler):
                 nbytes = int(length)
             except (TypeError, ValueError):
                 nbytes = 0
-            files = subprocess.Popen(cmdline,
+            p = subprocess.Popen(cmdline,
                                  stdin = subprocess.PIPE,
                                  stdout = subprocess.PIPE,
                                  stderr = subprocess.PIPE