---
 src/if-linux.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/if-linux.c b/src/if-linux.c
index 2e519f2..9d9f161 100644
--- a/src/if-linux.c
+++ b/src/if-linux.c
@@ -26,6 +26,10 @@
  * SUCH DAMAGE.
  */
 
+#ifndef RTA_EXPIRES
+#define RTA_EXPIRES 21
+#endif
+
 #include <asm/types.h> /* Needed for 2.4 kernels */
 
 #include <sys/types.h>
-- 
2.34.1