diff --git a/src/hathreads.c b/src/hathreads.c
index 4c795b1..470ee02 100644
--- a/src/hathreads.c
+++ b/src/hathreads.c
@@ -50,7 +50,7 @@
 
 	fdtab[rfd].owner = NULL;
 	fdtab[rfd].iocb = thread_sync_io_handler;
-	fd_insert(rfd);
+	fd_insert(rfd, MAX_THREADS_MASK);
 
 	all_threads_mask = mask;
 	return 0;