diff --git a/src/timer.c b/src/timer.c
index 4ac9f7b..b50ba46 100644
--- a/src/timer.c
+++ b/src/timer.c
@@ -62,7 +62,6 @@ extern int ether_fd;
 
 #ifdef LINUX
 #include <sys/ioctl.h>
-#define _BSD_SOURCE
 #include <signal.h>
 #include <sys/times.h>
 #endif