# define _XOPEN_SOURCE_EXTENDED
#endif
#ifdef OPENSSL_SYS_UNIX
-# define __USE_XOPEN_EXTENDED /* For Linux and probably anything GNU */
+# define _XOPEN_SOURCE
+# define _XOPEN_SOURCE_EXTENDED /* For Linux and probably anything GNU */
#endif
#include <string.h>
#include <openssl/engine.h>
# define _XOPEN_SOURCE_EXTENDED
#endif
#ifdef OPENSSL_SYS_UNIX
-# define __USE_XOPEN_EXTENDED /* For Linux and probably anything GNU */
+# define _XOPEN_SOURCE
+# define _XOPEN_SOURCE_EXTENDED /* For Linux and probably anything GNU */
#endif
#include <string.h>