diff --git a/query.py b/query.py
index e24ffc6..b157f11 100755
--- a/query.py
+++ b/query.py
@@ -63,7 +63,7 @@ def query (cmd, *args):
     elif cmd == 'file':
         version = args[0]
         path = args[1]
-        ext = path[-2:]
+        ext = os.path.splitext(path)[1]
 
         if ext == '.c' or ext == '.h':
             tokens = scriptLines ('tokenize-file', version, path)
diff --git a/update.py b/update.py
index b5fb990..f78b997 100755
--- a/update.py
+++ b/update.py
@@ -74,7 +74,7 @@ def updateDefinitions (blobs):
         hash = db.hash.get (blob)
         filename = db.file.get (blob)
 
-        ext = filename[-2:]
+        ext = os.path.splitext(filename)[1]
         if not (ext == '.c' or ext == '.h'): continue
 
         lines = scriptLines ('parse-defs', hash, filename)
@@ -97,7 +97,7 @@ def updateReferences (blobs):
         hash = db.hash.get (blob)
         filename = db.file.get (blob)
 
-        ext = filename[-2:]
+        ext = os.path.splitext(filename)[1]
         if not (ext == '.c' or ext == '.h'): continue
 
         tokens = scriptLines ('tokenize-file', '-b', hash)