Issue #3748: platform.architecture() printed vogus message on windows.

Reviewed by Marc-Andre Lemburg.

Lib/platform.py

@@ -964,6 +964,9 @@ def _syscmd_file(target,default=''):
         case the command should fail.
 
     """
+    if sys.platform in ('dos','win32','win16','os2'):
+        # XXX Others too ?
+        return default
     target = _follow_symlinks(target)
     try:
         f = os.popen('file %s 2> /dev/null' % target)