diff --git a/ifstatd.c b/ifstatd.c
index bd78b74..b529c86 100644
--- a/ifstatd.c
+++ b/ifstatd.c
@@ -24,6 +24,7 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
+#define _GNU_SOURCE
 #include <sys/cdefs.h>
 #include <sys/types.h>
 #include <sys/param.h>