diff --git a/tools/socks.sync b/tools/socks.sync
index a5033a5..454fed9 100755
--- a/tools/socks.sync
+++ b/tools/socks.sync
@@ -16,7 +16,7 @@ rsync_path = os.getenv('RSYNC_PATH', default = 'rsync')
 
 
 def in_source_tree():
-    return os.path.isfile('tools/sync.py')
+    return os.path.isfile('tools/socks.sync')
 
 
 def create_sample_config():