diff --git a/auto/bin/parse_xml.py b/auto/bin/parse_xml.py
index ff5567f..8c9e7e8 100755
--- a/auto/bin/parse_xml.py
+++ b/auto/bin/parse_xml.py
@@ -147,13 +147,13 @@ if __name__ == '__main__':
 
     if len(options.core):
         for i in api[2].keys():
-            f = open('%s/%s'%(options.core, i), 'w')
+            f = open('%s/%s'%(options.core, i), 'wb')
             writeExtension(f, i, api[2][i], api[0], api[1])
             f.close()
 
     if len(options.extensions):
         for i in api[3].keys():
-            f = open('%s/%s'%(options.extensions, i), 'w')
+            f = open('%s/%s'%(options.extensions, i), 'wb')
             writeExtension(f, i, api[3][i], api[0], api[1])
             f.close()