diff --git a/libavformat/applehttp.c b/libavformat/applehttp.c
index 3d8b61d70c..3aa7ed4239 100644
--- a/libavformat/applehttp.c
+++ b/libavformat/applehttp.c
@@ -25,6 +25,7 @@
  * http://tools.ietf.org/html/draft-pantos-http-live-streaming
  */
 
+#define _XOPEN_SOURCE 600
 #include "libavutil/avstring.h"
 #include "avformat.h"
 #include "internal.h"