diff --git a/src/api.c b/src/api.c
index b8c999f3..846235a9 100644
--- a/src/api.c
+++ b/src/api.c
@@ -1,3 +1,6 @@
+/* for syscall() */
+#define _DEFAULT_SOURCE
+
 #include <stdbool.h>
 #include <stddef.h>