diff --git a/api_test/harness.c b/api_test/harness.c
index 6b7336f97..28812d5a2 100644
--- a/api_test/harness.c
+++ b/api_test/harness.c
@@ -1,4 +1,6 @@
+#define _BSD_SOURCE
 #define _DEFAULT_SOURCE
+#define _POSIX_SOURCE
 #include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>