diff --git a/ffplay.c b/ffplay.c
index efc079be4f..56b39d2f4b 100644
--- a/ffplay.c
+++ b/ffplay.c
@@ -19,6 +19,8 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
+#define _XOPEN_SOURCE 600
+
 #include "config.h"
 #include <inttypes.h>
 #include <math.h>